4336 4340.output

* GB784743 (A)

Description: GB784743 (A) ? 1957-10-16

Improvements in velocity modulated discharge tubes

Description of GB784743 (A)

A high quality text as facsimile in your desired language may be available amongst the following family members:

CH333341 (A) FR1119605 (A) US2867747 (A) CH333341 (A) FR1119605 (A) US2867747 (A) less Translate this text into Tooltip

[83][(1)__Select language] Translate this text into

The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

PATENT SPECIFICATION Inventor: CLAYTON ELLSWORTH MURDOCK 7824743 ': Date of application and filing Complete Specification: Aug 9, 1954. No 27053/56 (Divided out of No 784,742). Complete Specification Published: Oct 16, 1957. Index at acceptance:-Class 39 ( 1), D( 9 C: 9 D: 9 F: 9 G: 9 H: 10 D 11: 12 E: 16 A 2: 17 A 3: 46 A). International Classification:-H Olj. COMPLETE SPECIFICATION Improvements in Velocity Modulated Discharge Tubes We, EITEL MCCULLOUGH, INC, a Corporation organised and existing under the laws of the State of California, United States of America, and having a place of business at San Bruno, State of California, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following

statement: - This invention relates to electron-tubes of the velocity modulated type, having cavity resonators. The invention provides a velocity modulated type electron-tube, comprising an elongated evacuated envelope, an electron gun at one end of the envelope and a collector electrode at the other end, a straight tube extending axially of the envelope, providing a drift tube and forming side walls of the evacuated envelope, said tube comprising spaced sections with gaps therebetween, a plurality of cavity resonator portions disposed transversely of the envelope axis at the gaps, said resonator portions comprising metal end walls mounted on adjacent tube sections and extending outwardly from said sections, means providing vacuum-tight walls across the gaps, and a water jacket surrounding the tube section between a pair of adjacent resonator portions and comprising a sleeve which surrounds the last mentioned tube section and is secured at both ends to the adjacent end walls of the latter resonator portions. The features of the present invention are intended to be particularly useful in externally tunable klystrons of the type disclosed in U S A Patent Specification No 2,619,611, issued November 25th, 1952, though they are not limited to use in such tubes Tubes of the type just mentioned may be required to handle considerable amounts of power and the present invention provides an efficient construction that makes this possible. lPrice 3 s 6 d l A preferred embodiment of the invention will now be described with reference to the accompanying drawing in which: Figure 1 is a side elevational view of part 50 of a three-resonator klystron; Figure 2 is an axial sectional view of the same, and Figure 3 is an enlarged fragmentary view showing the construction of a cavity resonator portion 55 The tube illustrated is particularly designed as an amplifier in the UHF region having a power rating of several kilowatts CW. Figures 1 and 2 show the evacuated tube per se apart from the external structure In the 60 final use of such a tube suitable external resonator portions are applied as described in the above mentioned patent specification, one of such external resonator portions being indicated by the dotted lines 1 in Figure 1 65 The tube comprises an elongated generally cylindrical envelope having an electron gun 2 at one end and a collector electrode 3 at the other end The electron beam from the gun to the collector passes through a tube 70 made up of aligned metal sections 4, 6, 7 and 8 extending axially of the envelope and having gaps 9, 11 and 12 therebetween Such gaps are bridged by cavity resonator portions forming part of the tube envelope and gener 75 ally designated 13, 14 and 16.

Electron gun 2 includes a disk-shaped cathode 17 and a surrounding focusing electrode 18, the cathode being heated by a filament 19; all these elements are supported by 80 a glass stem 21 forming part of an end of the evacuated envelope Cathode 17 is preferably of a material such as tantalum heated by electron bombardment from the filament, all in accordance with conventional practice 85 The electron gun is housed in a cup-shaped metal section 22 of the envelope, which section is of iron and functions both as an anode for the gun and as a pole piece for a suitable external focusing magnet Stem 21 is sup 90 ported on the pole piece 22 An aperture 23 in the iron pole piece 22 is aligned with the 274,4 cathode and is coaxial with the tube formed by the sectons 4, 6, 7, 8. Collector 3 at the opposite end of the envelope to the electron gun comprises a hollow metal electrode 24 supported from a disk-shaped metal section 26 of the envelope. A glass envelope section 27 sealed between flanges 28 provides a supporting connection between the collector electrode and the envelope section 26 An aperture 29 in the metal section 26 is aligned with the collector electrode and is coaxial with the tube The metal section 26 is a disk of iron and also functions as a pole piece for the external focusing magnet. With the above described structure an electron beam from gun 2 is accelerated by a positive potential on the pole piece 22 acting as anode and passes through the tube sections 4, 6, 7, 8, past the interaction spaces provided by gaps 9, 11 and 12, and finally terminates on the collector electrode 3, the beam being directed down the tube sections by an external magnet associated with iron pole pieces 22 and 26 The three cavity resonators comprising portions 13, 14 and 16, coacting with the interaction spaces at gaps 9, 11 and 12, serve as the frequency determining elements of the device In the tube illustrated, which functions as an amplifier the input signal for modulating the electron stream is fed into the first resonator comprising the portion 13, and the radio-frequency output is taken from the third resonator comprising the portion 16, as is usual for three cavity type klystrons. As previously mentioned herein, the particular kind of tube shown is adapted for external tuning by the use of suitable external resonator portions, one of which is indicated by the dotted lines 1 in Figure 1: each complete resonator comprising a portion forming part of the envelope such as 16, and a cooperating external portion, such as 1. The use of such external resonator portions for tuning over a wide band of frequencies is possible, of course, because of the sealedoff nature of the resonator portions 13, 14 and 16 which comprise part of the evacuated SO envelope.

Continuing with the description of Figures 1 and 2, the end tube section 4 is brazed to the pole piece 22, and the other end section 8 is brazed to the section 26 The intermediSS ate tube sections 6 and 7, as has been said, are axially aligned with the end sections 4 and 8, and these several sections form parts of the side walls of the evacuated envelope. The resonator portions 13, 14 and 16, which are disposed transversely of the envelope axis, are mounted on the tube sections and form additional side wall portions of the evacuated envelope In other words, the resonator portions provide vacuum-tight walls bridging the gaps between the tube sections. Input resonator portion 13 comprises parallel disk-shaped metal end walls 31 and 32 brazed to the tube sections 4 and 6, these end walls also being preferably of copper 70 A cylinder 33 of insulating material is sealed between such end walls In the interest of mechanical strength and electrical properties the cylinder 33 is of a ceramic material, such as the alumina or zircon type ceramic 75 bodies Cylinder 33 is supported by axially extending flanges 34, preferably of copper, brazed to the opposing surfaces of side walls 31 and 32 The ceramic is metallically bonded to the copper flanges by known 80 ceramic-to-metal bonding techniques, such as by first metalising the ends of the ceramic by the molybdenum powder sintering process and then brazing the metalised ends to the metal flanges with silver solder or the like 85 Since the ceramic materials have a lower coefficient of thermal expansion than metals of good electrical conductivity, such as copper, the flanges 34 are given a U shape to provide folded back inner lips 36 connected go to the ceramic This provides a good mechanical arrangement and also sufficient flexibility in the structure to accommodate differences in expansion Another advantage of this construction is that the rounded faces 95 of the flanges i e the bights of the U's face each other and thereby provide desirable corona rings to reduce sparking between the resonator walls In combination with the Ushaped flanges, metal spacing rings 38 are 100 provided to project from the end walls to abut the ends of the ceramic These rings take axial thrust between the end walls and the ceramic and prevent the flexible flanges from collapsing when the tube is evacuated 105 When differential expansion occurs perpendicular to the axis of the tube the spacing rings deform slightly to accommodate this expansion Thermal expansion and contraction axially of the tube presents no problem 110 since in normal use of the tube it is always held so as to allow the slight movements involved. The intermediate resonator portion 14 is of similar construction, having end walls 39 115 and 41 with a ceramic cylinder 42; output resonator portion 16 is of like construction, having end walls 43 and

44 with a ceramic cylinder 46 In each of the three resonator portions the disk-like end walls have outer 120 edges providing terminals with which suitable contact fingers on the cooperating external resonator portions may be engaged. Provision is made in the tube illustrated for cooling the drift tube and associated 125 parts, such cooling being of special importance in a power tube of this kind where one is dealing with kilo-watts of power As best shown in Figure 2, metal sleeves 47 and 48 are provided about the tube sections 6 and 130 784,743 claimed an electron-tube comprising an evacuated envelope, an annular metal section and an annular ceramic section adjacent thereto which sections constitute a part of the envelope, flexible vacuum tight sealing 70 means between the adjacent parts of the sections, and an annular metal element having the form of a short length of tube which element extends in a generally axial direction between the adjacent parts of the sections 75 whereby to take axial thrust between them but does not provide a seal between said sections, the cross-section of said element being such as to permit deformation thereof on differential thermal expansion of the sections 80 in a direction perpendicular to the axis thereof. In Application No 23,084/54 (Serial No. 784,742) certain features connected with water jackets are claimed in combination 85 with the tube features just set forth.

* Sitemap * Accessibility * Legal notice * Terms of use * Last updated: 08.04.2015 * Worldwide Database * 5.8.23.4; 93p

* GB784744 (A)

Description: GB784744 (A) ? 1957-10-16

Improvements relating to record controlled recording apparatus


PATENT SPECIFICATION Inventor:-JOHN ALBERT FORMBY. Date of filing Complete Specification: May 18, 1955 Application Date: Feb 18, 1954 No 4829/J 4. Complete Specification Published: Oct 16, 1957. 784,744 Index at Acceptance:-Olasses 40 ( 1, H 11 B 11 (A: C: X); 40 ( 3), A 5 P( 1 B: 2 MB); ( 4), M 2 O(B 2 KI Y 4), C 27 (B 4: JX); and 106 ( 1), O ( 1 D: 2 B 2: 2 F: 26: EMX: 3 B: 6). International Classiiication:-B 41 j G 06 f G 08. COMPLETE SPECIFICATION. Improvements relating to Record Controlled Recording Apparatus. We, JOHN FORMBY & COMPANY LIMITED, a British Company, of 6 Bennetts Hill, Birmingham, Warwickshire, do hereby declare the invention for which we pray S that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement:- This invention relates to record controlled recording apparatus and provides means whereby a train of symbols recorded in any suitable form, as for example, on a primary magnetic track, may each individually be adapted to control a distinctive integer of a printing apparatus or the like The term "printing apparatus or the like" should be read as including high speed printing apparatus as hereinafter described or other form of printing or typing apparatus and all forms of punching or embossing whether on tape or cards or the like. According to the invention, there is provided record controlled recording apparatus wherein a train of symbols is adapted to control printing or like apparatus in accordance with the value of each distinctive symbol, comprising a cyclical magnetic track, a plurality of spaced recording heads opposed to said cyclical track, discriminating means adapted selectively to energise one such recording head in accordance with the value of a symbol supplied thereto in order to record on said cyclical track a spot at a position distinctive of the symbol number and value, and reproducing means controlling the printing or like means whereby said reproducing means is energised at a time dependent on the number and value of a symbol. More specifically and according to a further aspect of the invention, there is provided record controlled recording apparatus wherein a train of symbols is adapted to control, printing or like apparatus in accordance with the value of each distinctive symbol, comprising a cyclical magnetic track, a plurality of spaced recording heads opposed to said cyclical track, discriminating means adapted selectively to energise one such recording head in accordance with the value of a symbol supplied thereto in order to record on said cyclical track a

spot at a position distinctive of the symbol number and value, timing means and a plurality of reproducing heads spaced apart a distance such that, if the timing means emits pulses at intervals corresponding to the recording head spacing, the spot corresponding to a symbol is reproduced by a recording head distinctive of the symbol number and at a time distinctive of the symbol value, each said reproducing head controlling distinctive portions of said printing or like means. According to yet another aspect of the invention, there is provided record controlled recording apparatus comprising a primary track, a cyclical track moving in harmony with said primary track, a plurality of recording devices adjacent said cyclical track, means to energise said recording devices selectively in accordance with the nature of symbols on said primary track, a plurality of reproducing means adjacent said cyclical track and means to transmit, at intervals determined by the movement of the said cyclical track, actuating impulses from said reproducing means to printing or like recording apparatus. In order that the invention may be more I 784,744 clearly understood, roference is made to Figures 2 and 3 of the drawings accompanying the Provisional Specification and to the accompanying drawings. In the accompanying drawings comprising Figures 4 and 5 only:Figure 4 shows schematically the arrangement of one embodiment of this invention; and Figure 5 shows a primary magnetic track and the detailed form of a discriminator seen in Figure 4. In the drawings of the Provisional Specification: Figure 2 shows schematically a modified arrangement of a portion of Figure 4; and Figure 3 shows diagrammatically a portion of the printing apparatus controlled by the embodiment herein described. Referring now to Figure 4 of the drawings, a control wheel 1 and a record disc 3 are mounted upon a common shaft 5 The record disc 3 has a cyclical magnetic track 31 upon its periphery and it will be assumed that this track may be divided into 384 equally spaced intervals or "spot positions " The arrangement to be described is that in which a train of 16 symbols is to be recorded on the cyclical track 31, each symbol having the value 0-9, during a half rotation of the disc 3, i e a double train of 32 symbols for a complete rotation As described with reference to Figure 5 of the drawings, a primary magnetic track initially carries the train of symbols, each such "primary" symbol conveniently being in the form of a series of magnetised portions of the track; a discriminator, indicated generally in Figure 4 by the reference 2, sorts these primary symbols in accordance with their value and applies a single pulse to one of ten recording heads or devices 4 associated with the track 31 The result is that a single magnetised "spot" is applied to the track 31.

If the 384 equidistant positions on the cyclical track 31 are counted anti-clockwise, then the recording heads are placed at positions 17, 34, 51, 68, 85, 102, 119, 136, 153 and 170 Primary signals are presented to the discriminating unit at regular intervals and the disc 3 and wheel 1 rotate clcckwise through an angle corresponding to twelve spot positions between consecutive signals. Thus, if the first signal of a train of 16 signals gives rise to a spot on the track 3 ' at a position corresponding to one of the spot positions 17 170, aforesaid, according to the value of the signal, then the second signal of the train will give rise to a spot at one of the positions 29, 46 165, that is to say, twelve positions upstream of the corresponding positions for the first signal Similarly the third signal will give rise to a spot at one of the positions 41, 58 etc Since the first sixteen multiples of twelve are not divisible by seventeen, it is not possible for any two spots from a train of 16 symbols to coincide Furthermore, since they are all contained in half of the 70 three-hundred and eighty-four possible spot positions on the disc circumference, a further train of 16 symbols may be accommodated similarly on the other half. If reproducing means 6, e g a reproduc 75 ing head as used with magnetic tape, is placed anywhere in association with the track 31 other than on a minor arc joining two recording heads e g in a position corresponding initially to position 1 E 0, it is evident 80 that any spot on the track 3 ' will, at some time in the course of one rotation, give rise to a signal at the said reproducing head. An erasing magnet 7 may be placed, at say position 175, so that all spots are erased S: after they have passed under the reproducing head The output of this reproducing head is applied to an amplifier 8, the functioning of which is controlled by timing signals derived from timing means formed, by a 90 photo-electric cell 9 in juxtaposition to holes 11 in the wheel 1, the said holes being illuminated by a lamp 10 which is supplied with direct current, the said signals passing through an amplifier 11 before being applied 9 o 5 to control the amplifier as aforesaid Holes in the wheel 1 are provided at spot positions 17, 34, 51, 68, 85, 102, 119, 136, 153, 170 aforesaid together with the diametrically opposite spot positions The wheel 1, disc 100 3 are so orientated on the shaft 5 in relation to the photo-electric call 9 that the arrival of spots at the reproducing head derived from the first symbol of a train always coincides with the juxtaposition of the cell with 105 one of the holes 1 ' Thus, the amplifier with which the said reproducing head is associated is adapted to transmit only those pulses which arise from the first signal of a group Since the diametrically opposite 110 holes aforesaid have a like effect, the

said reproducing head will respond effectively to spots arising from the first and the seventeenth signals of a double train. Since the second signal of a train occurs I; at a later time, during which the disc 3 has rotated an angular distance corresponding to twelve spot positions, a spot arising from this signal will not arrive at the first reproducing head 6 at a time corresponding 1:2 o to the passage of a hole 1 ' under the photoelectric cell 9, so that signals derived from this spot will not pass through the amplifier 8 aforesaid If, however, a second reproducing head 6 is placed twelve spot posi 125 tions upstream of the first, namely at a position corresponding initially to spot position 192 and the second reproducing head is associated with a like amplifier 8 controlled from the same cell 9, it is evident that this 130 one half of the disc one of the coils becomes energised when the associated thyratron strikes, causing the capacitance to discharge, and during the other half cycle the other coil becomes energised in a like manner 701 Thus, the first coil associated with the first reproducing head is associated with the first of thirty-two printing wheels of a printing apparatus and the second coil is likewise associated with the seventeenth wheel In 75 like manner two coils associated with the second reproducing heads are associated with the second and eighteenth wheels of the printing apparatus as aforesaid Thus, in like manner every one of the thirty-two 80 printing wheels is associated with one of thirty-two coils grouped in pairs and each pair associated with one of sixteen reproducing heads. The printing wheels are all mounted on a 85 common shaft 24 which rotates at twice the speed of the disc 3, being driven by an appropriate train of gears comprising bevel gears 25 connected by a shaft 26 to mitre gears 27 On each of the wheels are ten 9 & printing characters corresponding to the ten numerical values 0-9 and so orientated on the wheel that consecutive characters subtend at the centre twice the angle subtended by successive recording heads 4 at the centre 95 of the disc 3 Printing is effected by pushing the paper against the printing wheel while it is in continuous motion This may be effected, for example, by causing the energised coil to exert a pull on an armature 100 and thence on a toggle linkage 28, thus exerting a pressure for a very short interval of time on the paper via a piston 29 or, alternatively, a hammer may be caused to strike the paper It is evident that the 105 printing wheels may be so orientated that the appropriate printing character comes into juxtaposition with the paper as the appropriate amplifier emits a signal causing the associated thyratron to strike and thus 110 causing the paper to be pressed momentarily against the paper, so pressing it against the print wheel as aforesaid.

Referring to Figure 5 of the accompanying drawings, an example is shown of a dis 115 criminating unit as represented in block form in Figure 4 This Figure also shows the primary magnetic track and its relation to the discriminating unit An electric motor 30 drives a sprocket 31 on which is 120 carried a sprocket film 31 a (as used for example in film studios), such film forming the primary magnetic track The motor also drives the shaft 5 via snur gears 32, 33 or by any other suitable means A sensing 125 head 34 in juxtaposition to the magnetic tape transmits electrical signals correspond. ing to any signals on the primary track via an amplifier 35 to be applied via suitable capacitances 36 and across suitable recti 13) second amplifier may be adapted to transmit signals corresponding to the second and eighteenth signals of a double train and to no others In like manner a further fourteen reproducing heads 6 (making sixteen in all) each associated with its own amplifier 8 and controlled by the common amplifier 11, may be positioned twelve spot positions apart progressively upstream of the second reprolo ducing head aforesaid Thus, each reproducing head effectively transmits one only of the signals derived from the sixteen symbols of a train Each of the amplifiers has its output applied to the control grid of a distinct thyratron valve in order to control a printing apparatus, as will appear below. Where the number of possible symbol values is large, say fifty, it may be impossible, owing to the physical size of the 2 o recording heads to arrange fifty of them on one half of the periphery of a disc without making the disc inconveniently large In such a case the heads may be arranged in cascade on two or more parallel cyclical 2 tracks of the same disc Figure 2 of the drawings of the Provisional Specification shows such an arrangement, wherein a multiplicity of recording heads 12 are suitably spaced round one track, with one read head 13 and one erasing magnet 14 Any spot made by any one of the recording heads is reproduced by the read head 13, amplified by an amplifier 15 and re-recorded on the second track by a re-record head 16 Adjacent this second track are a multiplicity of reproducing heads 17 arranged after the manner described in relation to Figure 4, and one erasing magnet 18 It is evident that by this arrangement a smaller disc may be used than would otherwise be possible. Furthermore, the method may be extended to any number of tracks Thus, there might be twenty-five recording heads on read head and one erasing magnet on one track, and, on another parallel track, one re-record head recording any spots derived from the twentyfive recording heads aforesaid, together with a further twenty-five recording heads so that the spots derived from all fifty recording heads may be effectively assembled on one track even though it would

not be possible to assemble all fifty heads thereon. Thus, provided that the timing means which controls the various reproducing head amplifiers is sufficiently precise in the timing of its pulses there need be no restrictions on the number of possible values, or the numiber of symbols in a train. Referring to Figure 3, the output of each amplifier 8 is applied to a thyratron type valve 19 in association with two capacitances 20 in series with coils 21 and pairs of contacts 22 The contacts are operated by a cam 23 which moves on the same shaft 5 as the disc 3 and wheel 1 Thus, during 7004,7 i 44 tiers 37 to the cathodes of two trigger tubes 38 These are of the type G'/371 K manufactured by Standard Telephones and Cables Limited and are high speed primed trigger 3 tubes, the priming gap being omitted from the drawing for convenience The tubes are provided to supply input pulses to two cold cathode multi-cathode gas glow discharge tubes 39 of the type G 10/241 E also manufactured by Standard Telephones and Cables Limited Full details of the circuits associated with these valves can be obtained from the manufacturers and for convenience only the essential circuits details are shown here It is supposed that trains of symbols are recorded sequentially on the primary magnetic track and that each symbol is represented by a series of pulses, the number of pulses representing the value of the said symbol The mode of operation of the discriminating unit may best be understood by considering it first in a simplified form. In this form, each successive symbol gives rise to a series of pulses which passes into a ten cathode gas glow tube 39, thus causing the glow to step to the appropriate cathode, and thus priming an associated trigger tube one of which is associated with each of the ten cathodes A timing signal derived from the wheel 1 is applied to all ten of these tubes 40 simultaneously and the one which is primed strikes, so applying current to the operating coil 41 of the recording head 4, the ten recording head coils forming the cathode loads of the ten tubes 40 The anodes of these tubes are supplied from a capacitance 42 via resistances 43, the said capacitance being connected to the H T. positive supply via a larger resistance 44. Thus the primed tube passes current for a very short time, so causing a spot to be recorded on the cyclical track 31 and is then extinguished After one of the ten trigger tubes 40 has been primed as aforesaid, the gas glow tube 39 must be zeroised, that is to say, the glow must be returned to the zero cathode In order to avoid the need for great precision in timing and to allow more time for the glow to transfer to the zero cathode it is preferred to use two tubes 39 instead of one so that each has alternate symbol pulses applied to it

and each is zeroised while the other is receiving pulses. The two valves have their corresponding w 5 cathodes joined together via rectifiers 45, the point between each Dair being joined via a resistance 46 and a further resistance 47 to the trigger electrode of one of the ten trigger tubes 40 By this arrangement the trigger tube is Drimed if the associated cathode of either of the two gas glow tubes carries the glow In the case of the zero cathodes it is necessary that the associated trigger tube should be primed only if both the zero cathodes carry the glow In this case the rectifiers 45 a are reversed and a further bias resistor 45 b is provided to form a conventional coincidence circuit The two trigger tubes 38 are controlled by a further pair of trigger tubes 48 which form a flip 7 o flop The cathode load of each tube 48 includes the operating coil 49 of a high speed relay and the voltage across this coil when current is passing is sufficient to provide priming bias to the trigger electrode of 7,3 the associated trigger tube 33 Associated with the relay coils are nairs of contacts 50 by means of which a zeroising potential of v is applied across a rectifier 51 to the zero cathode of the alternate gas glow < tube, thus providing that while the one gas glow tube is receiving pulses the other is being zeroised A set of thirty-two equally spaced holes in the disc 1 (not shown in Figure 4) correspond to the ends of consecu,tive symbol intervals and with the holes is associated a lamp 52 provided with direct current in order to avoid fluctuations of light intensity and on the other side of the disc is an optical slit unit 53 comprising a (Z. metal tube in which is mounted a narrow slit 54 and a lens 55 so that an image of the hole in the disc may be focused on the slit and light passing through falls on the sensitive surface of a photo-electric cell 58 The fig metal tube may conveniently be mounted in and eccentric bush (not shown) so that small adjustments of the timing of the pulses emitted by the photo-cell may be effected. The output of the said photo-cell 56 is Ion applied via a suitable amplifier 57 and via capacitances 58 to the appropriately biased trigger electrodes of the two trigger tubes 48 aforesaid The anodes of these tubes are coupled by a capacitance 59 so that the pair lid. function as a flip flop and thus provide, as aforesaid, for the two gas glow tubes 39 to function in respect of alternate symbols from the primary magnetic track 31 a The common timing pulse to the ten trigger tubes 11 i) is provided by a similar optical system 60 associated with the same set of thirty-two holes, together with a photo-cell 61 and amplifier 62, the output of which is applied to the ten points marked "x" in Figure 5 113 and thence via capacitances 63 to the trigger electrodes Full details including appropriate component values for the operation of valves type G 1/371 K and G 10/241 E can be obtained from

the manufacturers 1241 Referring again to Figure 4, the photoelectric cell 9 depicted diagrammatically therein may be assumed to be associated with an optical system (not shown) which is similar to the optical system 53, but asso 123 ciated with the set of holes 1 ' in special positions as described above in relation to Figure 4. It will be appreciated that the correct functioning of the apparatus as described 130 ? 784,744 thirty-six intervals between the recording of 65 the first and fourth symbols. Thus to sum up the embodiment described, it may be stated that the primary track of the film 31 a carries trains of sixteen symbols (or double trains of 32 symbols) 70 and the value of each symbol is given by the number of pulses it generates in the sensing head 34 In accordance with this value, a single one of ten recording heads 4 is energised to apply a spot to the cyclical /5 track 31 By the correlation of the spacing of the recording heads 4 with the speed of movement of the track 3 ' between successive symbols, the position of this spot uniquely determines the symbol value 80 ( 0-9) and symbol number ( 1-16) Sixteen reproducing heads 6 scan the track 3 ' and have their outputs controlled by timing means 9, 10 in such manner that the spots give rise to outputs only from the repro 85 ducing head having the same symbol number and the time at which this output occurs is distinctive of the symbol value Each reproducing head is associated with a distinctive printing wheel (or selectively with 90 two such wheels for double symbol trains) and the wheels rotate in synchronism with the track 3 ' in such a manner that when the printing apparatus is activated by said output, the printing wheel has turned 95 through an angle appropriate to the symbol value thereby to print 16 (or 32) digit numbers on each line of the paper. It will also be appreciated that with appropriate modification of the discriminat 100 ing unit provision may be made for more than ten symbol values so that the invention may be applied to the printing of letters as well as numbers by means of an appropriate code For example thirty-six distinct sym 105 bol values could be employed and these could be recorded preferably on two primary tracks In this case the discriminating unit would be modified so that each gas glow tube would be replaced by a set of four 110 tubes connected in a ring so as to provide thirty-six distinct cathode outputs and each of these outputs would be applied to a distinct one of thirty-six trigger tubes each associated with a distinct recording head 115 A suitable set of four gas glow tubes is shown in the publication Electronic Engineering of June, 1952, and with some obvious modifications this could be used to provide thirty-six outputs in response to thirty-six 120 symbol values as aforesaid. It is known that printing by means of continuously rotating printing

wheels in the manner described can be effected at speeds up to fifteen lines per second or the like 125 Limiting factors are provided by the need to index the paper between consecutive lines and by errors in timing of the striking depends essentially upon an appropriate positioning of the ten recording heads 4 and the sixteen reproducing heads 6 in relation to the cyclical magnetic track 3 Thus, in the example described, the track 31 is considered to be divided into 384 eaual intervals and the recording heads are placed seventeen intervals apart and the reproducing heads twelve intervals apart The total angle subtended at the centre of the disc from the first recording head to the last is 17 x 9/384 of 360 degrees, which is approximately 144 degrees It is to be noted that the ten printing characters of Figure 3 must subtend an angle at the centre of the printing wheel of twice this amount or 288 degrees. This is a suitable Figure as it leaves a substantial portion of the printing wheel clear in order to facilitate movement of the paper while the wheel is in motion It is to be noted that 17 is a prime number and that the first sixteen multiples of twelve do not coincide with any multiples of seventeen. This is important in order to ensure that spots arising from different symbols of a train do not clash with each other It is also to be noted that 384 = 32 x 12 and that this relationship determines the relative positions of the sixteen reproducing heads. It will be appreciated that the particular figures in this example are not the only ones that can be used There is an upper limit to the number of spot positions determined by the number of distinct magnetic spots which may be reliably recorded per inch of cyclical track 31 and also by consideration of the size of the holes 11 and the backlash in the gears connecting the magnetic sprocket 31 and shaft 5 Within these limitations, any suitable angular distances for the recording and reproducing heads may be chosen For example, if it is desired to print 64 characters in two rotations of the printing wheels, it is necessary to choose a figure for the distance apart of the recording heads such that no multiple of it is divisible by any of the first thirty-two multiples of the figure which represents the distance apart of the reproducing heads It may readily be seen that in this case it would be possible to suppose the cyclical track 3 ' divided into 768 equal intervals and the recording heads could be thirty-five or thirty-seven intervals apart and the reproducing heads twelve intervals apart If, however, the recording heads were placed thirty-four of thirty-six intervals apart clashes would occur For example, in the case of thirty-six interval spacing being chosen, then obviously a spot made by the second head in res Donse to the first symbol would coincide with a S Dot made by the first head in response to the fourth symbol

since the track would have moved forward 784,744 mechanism which tend to make the printed impressions high or low, thus giving the printed line a wavy appearance at high speeds The present invention provides an economical means of controlling such a printing apparatus It is evident that many modifications of design are possible according to the speed and degree of accuracy required Such considerations may be balanced against considerations of cost. Thus, if half the speed of printing and the same degree of error as in the above example, could be tolerated, it would be possible to use eight reproducing heads only instead of sixteen In this case the printing wheels rotate four times for each revolution of the disc 3 Where higher speed and greater accuracy are required, on the other hand, thirty-two reproducing heads may be used, in an arrangement as shown in Figure 2 of the drawings of the Provisional Specification in this case the printing wheels rotate at the same speed as the magnetic disc 3.


* GB784745 (A)

Description: GB784745 (A)

No title available


PATENT SPECIFICATION Inventor: -DOUGLAS ERNEST ELLIOTT. 784,745 f/ Jy Date of filing Complete Specification: Feb 11, 1955. Application Date: Feb 25, 1954 No 56071/54. Complete Specification Published: Oct 16, 1957. Index at Acceptance:-Classes 51 ( 11, A 1 D, B 27 A, BA( 25 R: 26);

and 51 ( 2), B 27 B, BA 9, BCB. International Classification:-B 01 c F 23 c. COMPLETE SPECIFICATION. An improved Combustion Chamber. We, POWER JE Ts (R Es EA Rc H AND DEVELOPMENT) LIMITED, a British Company, of 25 Green Street, London, W A, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement:- This invention relates to an improved process for carrying out reactions, including partial reactions, at high temperatures and to apparatus therefor. Particularly but not exclusively the invention relates to a process, and to combustion 13 apparatus therefor, including partial combustion for gasifying (to which the invention is particularly applicable) to produce combustible gas, as well as certain metallurgical processes and furnaces, to a combustion process and chamber burning fuel to produce hot gaseous combustion products for use, for example as working fluid in gas turbines, and possibly even to steam boiler furnaces. To save time (by speeding up reactions), to save capital cost, to improve the nature of a process and for other purposes it is often desirable to operate at a temperature above 1200 'C and possibly above 2000 'C Thus for the efficient combustion of certain fuels and more particularly for promoting the weakly exothermic reactions of gasification of solid and liquid fuels with steam and oxygenbearing gases, it is extremely important to maintain temperature above 1200 'C and there is usually a continual gain in rate of reaction with increase of temperature up to at least 18000 C. The invention aims at permitting these high temperature while avoiding considerable transfer of heat to the combustion chamber wall The smaller the combustion chamber, the more serious is the loss due to this lPrice 3 j 6 d l transfer To reduce transfer, a metal wall may be lined with a heat-insulating refractory but if the reaction produces hot slag this will attack and erode the refractory. No refractory is yet known which will long withstand very high temperatures combined with the attack for example of hot liquid slag from coal Uninsulated metal walls must be externally cooled-e g water-cooled -to avoid over-heating and the heat loss is then a considerable proportion of the total heat released Any slag formed from the fuel will build up a layer on such a metal wall which is solid adjacent to the wall but is molten on its inner surface This slag layer is a good heat insulator, but if the temperature is very high the molten slag drains off and the layer thickness is usually

thereby kept down to less than 0 3 inch Despite the low conductivity of slag such a very thin insulating layer still permits a very high rate of transfer of heat to the walls. The invention consists in the process of carrying out a high temperature reaction in a space within a rotating combustion chamber having a layer of heat insulating material which is molten at least on its inner surface, formed on the chamber wall which includes supplying reactants into the reaction spade and rotating the combustion chamber at a speed sufficient to build up and maintain, under centrifugal force, a layer of heat insulating material thick enough to provide heat insulation for the reaction space and withdrawing material in excess of that required to form the layer from the chamber. The high temperature reaction may be one in which a chemical product of the process is molten at the reaction temperature The rotation of the chamber is then such as to build up and maintain, under centrifugal force, a layer of the product thick enough to 701 753 SO _4 W21 c provide insulation for a central reaction space within the chamber, whilst the molten product in excess of that required to form the layer is withdrawn from the chamber. As applied to the gasifying or burning slag-forming fuel, however, the slag formed from the reaction is built up and maintained as a centrifugally retained layer of sufficient thickness to provide heat insulation for a central reaction space Where the fuel used in the process is such as to produce no appreciable slag some heat insulation, or slag-forming, material which is molten at reaction temperature, is introduced into the rotating combustion chamber Hitherto the slag layer thickness has been a fraction of an inch whereas in apparatus, according to the present invention, the thickness will be several inches-usually of the order of one foot Thus it is possible to operate at temperatures above 1200 'C of 1500 'C in a chamber lined with fused coal ash of a thickness of the order of one foot, which will, at its inner surface, be molten and at a temperature not much below the reaction temperature but at its outer surface will be solid and at a comparatively low temperature. The invention further consists in apparatus for combustion reactions taking place at 31 high temperatures incorporating a rotary combustion chamber having a circumferential wall and end walls for retaining a layer of molten heat insulating material on the circumferential wall thick enough to provide heat insulation for a central reaction space, a mounting for the chamber with provision for rotating the chamber around its axis at such a speed as to provide the centrifugal force necessary to build up and maintain the desired thickness of layer, means for admitting combustion reactants into the chamber and means for withdrawing therefrom molten heat insulation material in excess of

that required to form the layer during rotation of -1 the chamber. The term " combustion chamber " has been used, in defining the invention, to mean the vessel wherein the heat-evolving chemical reaction e g combustion or partial o combustion-takes place The slag may be fused ash evolved by the combustion of fuel, but where the reaction will produce nothing to form an insulating layer on the walls, ash or refractory pebbles may be introduced into oo the chamber where they will be fused by the heat Certain processes-especially metallurgical processes-which do not produce ash may nevertheless provide a layer which will build up on the wall and partially solidify, to serve as heat insulation. For lack of a more comprehensive name, the term "slag" is used, in defining the invention, to include any substance evolved by the reaction to form a heat-insulating 6., layer on the walls, as well as slag or the equivalent separately introduced into the chamber. One particular construction, according to the invention, of rotary cyclone or vortex combustion chamber suitable for the com 70 bustion or gasification of fuel such as pulverised coal, is shown in the accompanying drawings of which:Figure 1 is a vertical half-section; Figure 2 is a half plan section on II-II 75 of Figure 1; and Figure 3 is a detail, looking along arrow III of Figure 1. In these drawings the combustion chamber includes a vertical metal cylinder 16 open 80 centrally at the top, with an inturned top rim la wide enough to retain slag to the thickness desired at the top (which may be several inches), an axially extending flange le around the inside of the rim la, and a lower 85 and centrally apertured part lc (which could be paraboloidal but is shown as conical) tapering towards its lower end This partly cylindrical and partly tapered chamber is rotatable about its axis; accordingly the 90 cylinder is supported by a radial-thrust bearing arrangement around its outside wall, as hereinafter described Enveloping the cylinder lb is an outer casing 2 which supports the bearings The top of casing 2 95 is partly closed, except for the necessary air and fuel inlets and gas outlet, by a circular stationary top cover 3, and a circular stationary centrally-apertured top plate 4. Welded to cylinder lb at intervals around its 100 periphery are outwardly projecting bearing brackets 5 which are of built-up plate construction These carry an outer ring 6 serving as a bearing race Ball bearings 7 between outer race ring 6 and an inner race 8 105 centralise and support the weight of the combustion chamber Race 8 is carried oln support ring 9 mounted on brackets 10 in casing 2 To rotate the chamber, an electric or other motor 11 drives, through coupling 12, 110 a shaft 13 which passes into the casing 2 through a gland 14 and carries a pinion 15 meshing with a toothed ring 6 a which

is fastened around the cylinder lb and secured thereto through brackets 5; the toothed 115 ring 6 a is shown as integral with the outer race ring 6. Mounted on and supported by the top plate 4 and extending centrally through the top plate into the interior of the combustion 121) chamber is an outlet tube 16 for egress of the gaseous products The space around tube 16 serves as an annular inlet passage for combustion air entering by inlet 4 b (Figure 2). Vanes 22 secured to and disposed in a ring 123 around tube 16 are inclined so as to impart swirl to the incoming air, as shown in the part development view Figure 3 Also secured to and disposed around the tube 16 is at least one and preferably two ducts 23 13 ( 784,745 These dimensions, and the cylinder dimensions are chosen to give the desired thickness of layer, according to the heat insulation desired To aid in quickly forming the necessary internal diameter of combustion 70 space, prepared molten slag may be poured in Preferably, the chamber 1 is given an initial lining of cement or other heat resistant material to a thickness less than the total desired The slag layer which forms may 75 attack this material and gradually replace it until the whole thickness of lining is of slag. When the desired layer thickness has built up, surplus slag in liquid form runs down into the water in the collector 19; steam 80 thereby produced enters the chamber 1. In an alternative method of operating the equipment described in which the reactants form no appreciable slag in the chamber, then some slag-forming material-e g ash 85 or refractory pebbles-may be introduced either through the inlet 45 or with the reactants, and fused by the heat of the reaction; the resulting slag particles which collect are built up centrifugally to complete 90 the thick layer S by rotation of the chamber. Or alternatively the chamber may be lined with cement or other material, as aforesaid, which fuses at the combustion temperature. The cooling air entering the outer casing by 93 inlet 3 a and swirling around the combustion chamber cools the outer surface of the chamber wall and so keeps the bearings cool. The air passes between the chamber wall and an enveloping wall 2 e and thence to the 100 outlet 2 c Some slag will probably collect inside outlet tube 16, to a comparatively small thickness, but in any case this tube 16 will get very hot inside and serve to transfer heat to the comparatively cool incoming 105 air around its outside surface. The invention is not limited to the construction shown Thus the arrangement may be such that surplus slag may be centrifuged out of the top of the combustion 110 chamber, instead of discharged from the bottom The slag may spray over the top rim either continuously, or

intermittently during temporary speeding-up of the rotating cylinder, and preferably such that the slag 115) sprayed over solidifies in small lumps; this slag falls into a collector on the top of the outer casing 2 With slag spraying from the top, the bottom of the combustion chamber may be completely closed; there is then a 120 heat-insulating layer between the combustion space and the bottom of the chamber of sufficient thickness to provide adequate heat insulation therefor. The invention is not limited to a cyclone 125 or vortex chamber but may be applied to a chamber with a straight-through flow In one such construction the rotary vertical cylinder is open at both ends but has at each end an inturned rim such as la of sufficient 13 X) for incoming fuel with carrier air Each duct 23 is also inclined as shown in Figure 3 to constitute an inclined port admitting the fuel swirl A labyrinth seal is formed by a cylindrical baffle 4 a on plate 4 and a similar baffle Id on the top rim la of chamber 1. An inlet 3 a admits cooling air to flow through the outer casing 2 to the air outlet 2 c; the air pressure in the casing may be sufficient to oppose any appreciable leakage into the casing past the labyrinth seal. The lower part 2 a of casing 2 is of tapered form around the corresponding part lc of the chamber 1 A slag-outlet tube 17 1.5 depending from the bottom of part lc and a corresponding enveloping tube 18 depending from the bottom of part 2 a form a seal by dipping into water in the stationary slagcollector 19 on base 20 It is assumed that o 20 the pressure in the combustion chamber is low enough for the collector 19 to be open to atmospheric pressure and that there is no need for a closed collector and means for pumping away the collected slag The casing 2 and motor 11 are carried by the upright columns of a support structure 21 standing up from the base 20 A tube 24 extending down beside the outlet tube 16 allows means to be inserted on occasion to ignite the fuel in chamber 1. In operation, pulverised coal or other ash bearing fuel, carried by air under pressure, enters the chamber 1 by ducts 23 and will swirl about the vertical axis of the , chamber The main supply of combustion air enters the chamber, with similar swirl in the same direction, from inlet 4 b and mixes with the fuel The mixture is ignited in the chamber The air and burning fuel therein travel inwardly in a spiral vortex within the chamber to the central outlet formed by tube 16; the fused ash particles evolved are thrown centrifugally outwards to build up a layer S on the walls of chamber 1 This may , be solid in contact with the wall, but the inner surface S, of the layer wsill remain molten If the cylinder lb were stationary, according to former practice, all the molten slag would run down to the bottom and drop he into the collector 19 With rotation of the cylinder lb by motor 11,

according to the invention, the liquid slag will spread out under centrifugal and gravitational action in the well-known manner of liquid in a vessel rotating about a vertical axis, to form a layer having an inner surface S, which is paraboloidal The bottom portion lc retains slag and allows a thick layer to build up. The top inturned rim la is wide enough to retain slag to the thickness desired therewhich may be several inches If the top internal diameter is for example to be three feet and the height of the paraboloid is to be three feet, the cylinder is rotated at not 6 i 5 much more than one revolution per second. 784,7 j 45 width to retain the desired thickness of layer of slag The cylinder is supported by bearings as described Air and fuel are introduced into the chamber through inlets in a stationary bottom plate around which the lower end of the cylinder revolves. Gases discharge through the open upper end of the cylinder Slag deposits on the inner wall of the cylinder, as already described; surplus slag from the thick heat insulating layer may fall from the bottom of the cylinder or be centrifugally sprayed over the top of the cylinder into a collector on top of the outer casing for collection and removal as already described The combustion air may be swirled and this will tend to throw ash outwards on to the wall of the chamber. Alternatively the air and fuel inlets may be at the top and the gas outlet at the bottom. It will be understood how the latter construction may be modified so that the combustion chamber is horizontal and rotates about a horizontal axis For the slag layer to have an internal diameter of 2 feet the speed need only be 60 R P M and need be only 35 R P M for 6 feet internal diameter, depending upon the density of the slag. In any of the above-described constructions the motor 11 and pinion 15 may be omitted and the combustion chamber rotated by the action of the incoming air-or possibly of the outgoing gas-on vanes, turbineblading or the equivalent attached to the rotary chamber. From the foregoing it will be understood how the described constructions can be adapted for use as the chamber for any of various different high-temperature reactions. Thus the invention may be applied to a high-temperature process wherein a chemical process has one product at least-which may be the desired product for which the process is carried out-which is heat insulating and molten at the reaction temperature, the enclosing layer being then of this product; excess over the desired thickness of layer issues from the chamber for utilization A typical process is one for making calcium carbide e

* Sitemap

* Accessibility * Legal notice * Terms of use * Last updated: 08.04.2015 * Worldwide Database * 5.8.23.4; 93p

* GB784746 (A)

Description: GB784746 (A) ? 1957-10-16

Improvements in or relating to protective housings for photographic rollfilm cameras


PATENT SPECIFICATION 784,746 E 2 | 'i Date of Application and filing Complete Specification: June 3, 1954. No 16438/54. Application made in Germany on July 2, 1953. Complete Specification Published: Oct 16, 1957. Index at Acceptance:-Class 98 ( 1), A 2 (A 5: C 8). International Classification:-GO 3 b. COMPLETE SPECIFICATION Improvements in or relating to protective housings for photographic roll film cameras We, REINHOLD HEIDECKE and HORST FRAN Kic, both German Nationals and trading together as Franke & Heidecke Fabrik. Photogr Prazisions-Apparate, of 196 Salzdahlumerstrasse, Braunschweig, Germany, do hereby declare the invention, for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to a protective housing for photographic roll film cameras of the kind having a taking chamber fitted in a common rigid casing and a reflex focusing view finder chamber arranged above the taking chamber. With this kind of camera, a common crank is provided for winding the film and tensioning the shutter, the crank being returned after each

feed operation into the initial position and in this position freeing the shutter release mechanism For indicating the film consumption, a measuring and counting mechanism driven by the film is provided, the scale of which is adapted to be read off through a window in the side wall of the camera Consequently, it has hitherto been necessary to provide a window in the protective housing for observing this counter mechanism Since the figures of this counter mechanism are generally quite small, it is difficult to read off them satisfactorily, particularly when the camera is being used for under-water photography. According to the invention, a protective housing for a camera of the kind referred to is provided with an external step-by-step counter device which is actuable directly by a crank arm carried by said protective housing, which crank arm can be coupled to the film winding crank of the camera. The crank arm on the protective housing is preferably formed with two projections having inclined surfaces which are located lPrice 3 s 6 d l so as to engage respectively one of a plurality of projections on a counter disc, whereby the latter is advanced by one half graduation of a scale thereon with each forward stroke and by half a graduation with each return of the crank arm. The essential parts of one constructional form of the invention are shown in the accompanying drawings, in which: Figure 1 is a sectional view of a portion of a camera protective housing fitted with the exposure counter device; and Figures 2 and 3 are detail front views on an enlarged scale, showing the counter device in two different positions. Mounted in the wall 1 (Figure 1) of the protective housing 2 is a shaft 3 which at its inner end carries a forked arm 4 engaging a knob 5 on the film winding crank 6 of the camera 7 Extending in the same angular direction as the arm 4 and on the outer end of the shaft 3 is a crank arm 8 with an actuating knob 9 This arm is made lightly resilient and the knob 9 is provided on the inside with a stud 10 which engages in a bore 11 in a housing attachment 12 when the crank is in the rest position. Located to one side of the bore 11 on the housing attachment 12, which is integral with a supporting handle 13, is an inclined surface 14 which lifts the stud 10 shortly before it reaches the rest position of the crank arm 8 and then allow said stud to spring into the bore Positioned on the inside of the crank arm 8 are two inclined projections 15 and 16 which are disposed so as to co-operate with pins 17 of a counter disc 18 rotatably mounted on the housing attachment 12 as said crank arm is actuated. This disc 18 carries a scale 19 which can be read off in relation to

an index mark 20. The angular spacing of the pins 17 and the graduations of the scale 19 correspond to the graduations of the film counter mechanism on the camera. so If the crank arm 8 is rotated from its rest position in the direction of the arrow " A " (Figure 2) the projection 16 engages over one of the pins 17 and rotates the scale plate 18 forward by a half graduation. When the crank has reached its limiting position, which is determined in well known manner by a film measuring mechanism, it has to be returned to the rest position in order to permit the shutter to be released. Shortly before reaching this position (Figure 3), the other inclined projection 15 engages over the same pin 17 and rotates the disc 18 by another half graduation, so that altogether it has been advanced by one graduation. At the same time, the next pin 17 has been moved into the path of the first inclined projection 16, so that the same operation is repeated when the crank arm 8 is actuated again. The effect of this operation is that the forward movement of the counter is always exactly one graduation with a complete operation of the crank arm, i e a forvard and return swinging movement Furthermore, unintentional incomplete operation of the crank arm is made apparent by the intermediate positioning of the counter disc, and in the rest position of the crank arm the external scale corresponds exactly to the indication of the counter mechanism in the camera. When a film has been fully exposed and the trailing end of the paper backing strip, prior to removal of the film, has to be wound on to the take-up spool, this can be effected without opening the protective housing by turning the crank arm 8 continuously in the clockwise direction (Figure 2) To enable the stud 10 to pass freely over the bore 11 and projection 14 during this operation an oppositely inclined surface 14 a is provided on the housing attachment 12 at the other side of said bore from the inclined surface 14 Similar rotational movement of crank arm 8 serves to take up the leading end of a new film after the housing has been closed over the camera.


* GB784747 (A)

Description: GB784747 (A) ? 1957-10-16

Improvements in or relating to the cold separation of gas-mixtures


A high quality text as facsimile in your desired language may be available amongst the following family members:

BE530347 (A) CH328571 (A) DE936215 (C) FR1153063 (A) NL93772 (C) US2867985 (A) BE530347 (A) CH328571 (A) DE936215 (C) FR1153063 (A) NL93772 (C) US2867985 (A) less Translate this text into Tooltip

[89][(1)__Select language] Translate this text into

The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

PATENT SPECIFICATION 784,747 Date of Application and filing Complete Specification: July 14, 1954. No 20627/54. Application made in Netherlands on July 15, 1953. D Complete Specification Published: Oct 16, 1957. Index at Acceptance: Class 8 ( 2), F 1. International Classification:-F 25 j. COMPLETE SPECIFICATION Improvements in or relating to the cold separation of gas-mixtures We, N V PHILIPS' GLOEILAMPENFABRIEKEN, a limited liability Company, organized and established under the laws of the Kingdom of the Netherlands, of Emmasingel 29, Eindhoven, Holland, do hereby declare the invention, for which we pray that a patent may be granted to us,

and the method by which it is to be performed, to be particularly described in and by the following statement: - This invention relates to low temperature gas-mixture fractionating systems comprising a gas refrigerator and a rectifying column from which thermal energy is withdrawn with the aid of the gas refrigerator The column is associated with an evaporator comprising a boiler and atmospheric or substantially atmospheric pressure prevails at the region at which a gas-mixture to be fractionated is supplied to the column The term " gas refrigerator " means herein a refrigerator comprising two spaces which vary continuously in volume with a substantially constant relative phase difference, one of them having a lower mean temperature and the other a higher mean temperature, said spaces being in communication with each other by way of a first heatexchanger, a regenerator and a second heatexchanger and containing a gas of invariable chemical composition which performs a thermodynamic cycle The heat-exchanger adjacent the first-mentioned space extracts heat from the medium to be cooled and is termed a freezer whilst the second transfers heat from the gas and is termed a cooler. One example of such a refrigerator is described and claimed in British Patent Specification No 695,857 Such refrigerators permit of obtaining very low temperatures, for example, 200 'C and lower, in one operational stage. With systems in which the gas-mixture to be fractionated is supplied to the column at lPrice 3 s 6 d l a pressure which is substantially in excess of atmospheric pressure, it will be possible, as a result of the difference between the pressure in the boiler and atmospheric pressure, to draw off from the boiler a part of the fraction of high boiling point in the vapour state. In a column, one fraction ascends as vapour and the other fraction descends as liquid It will be obvious that either fraction may itself be a mixture or that both fractions may be mixtures In this specification; the fraction which has ascended is referred to as the fraction of low boiling point and the fraction which has descended as the fraction of high boiling point. If, however, the gas-mixture to be fractionated is supplied at atmospheric or substantially atmospheric pressure, which may be done if thermal energy is withdrawn from the column with the aid of a gas refrigerator, said pressure difference will be zero or will be insufficient to draw off the vapour This will particularly be the case if, as often occurs in practice, the vapour drawn off the boiler is caused to pass through a heatexchanger in which the vapour is in heatexchanging contact with the gas-mixture to be fractionated. The present invention has for its object to provide a system which

permits the fraction of high boiling point to be drawn off from the boiler without the use of a pump or with the use of a pump of only low capacity. According to the invention, a gas-mixture fractionation system comprises a gas refrigerator as herein defined and a rectifying column from which thermal energy is withdrawn with the aid of the gas refrigerator and in which atmospheric or substantially atmospheric pressure prevails at the region at which a gas-mixture to be fractionated is supplied to the column, the resistance to flow of vapour ascending from the boiler so of an evaporator associated with the column to said region of the column being such that in normal operation of the system the pressure in the boiler is above atmospheric pressure The phrase "to draw off" as applied to a fraction means the removal of the fraction from the system The resistance to flow may be produced by giving the column suitable proportions and filling it with a suitable material. " Normal operation of the system " means herein continuous balanced operation of the system. Part of the vapour produced in the evaporator boiler may be drawn off from the boiler as a result of the pressure therein being above atmospheric pressure. A partition may be provided between the evaporator boiler and said region and a duct provided between the evaporator boiler and said region having a resistance to vapour flow such that said pressure above atmospheric pressure is produced Said partition may be provided at any suitable point, for example, within the column itself in which case it should comprise an opening for the passage of the liquid fraction of high boiling point. Provision may be made of a conduit between said region and the evaporator boiler, which conduit in normal operation of the system extends into the liquid fraction of high boiling point contained in the evaporator boiler and a quantity of said liquid The conduit may extend through the partition. With these latter constructions the resistance to vapour flow may result entirely from the size of the ducts, so that no particular requirements need be imposed on the column itself. The evaporator boiler may be immediately adjacent the column and the duct constituted by an aperture provided through the partition It will be obvious that more than one duct and/or more than one conduit may be provided. With the system according to the invention, less vapour should be drawn off if the thermal output of the gas refrigerator decreases and more vapour drawn off if the thermal output of the gas refrigerator increases Thus, the amount of gas-mixture to be fractionated and the

amount of fraction of high boiling point supplied to the column and drawn off from the column respectively may be in accordance with the thermal output of the gas refrigerator The operation of such a system is described and claimed in co-pending British Patent Specification No 20,175/54 (Serial No 759,315). The fraction of low boiling point may be condensed outside the column by means of the refrigerator, part of the condensate being returned to the column as reflux and the rest being drawn off through an outlet duct comprising a liquid lock. One embodiment of the invention will now be described, by way of example, with reference to the accompanying diagrammatic drawing, in which:Figures 1 and 2 show a gas-mixture fractionation system according to the invention, Figure 2 being a cross-sectional view taken on the line II-II of Figure 1, and Figure 3 shows a gas refrigerator suitable for use in a system according to the invention. Referring now to Figures 1 and 2 a rectifying column 1 comprises two cylindrical parts 2 and 3 whereof the former is larger in diameter than the latter The extension of the wall 4 defining the part 2 surrounds the wall 5 defining the part 3, the walls 4 and 5 being separated by an annular E space 7 The part 3 of the rectifying column 1 is separated from the boiler 6 of an associated evaporator by a partition 8 through which pass a duct 9 and a conduit by which the space within which frac 9 tionation takes place and the evaporator boiler 6 are connected with each other The conduit 10 reaches approximately to the bottom 11 of the boiler 6 which comprises projections forming part of a heat-exchanger 9 A pipe 13 provides connection to an opening 12 in the boiler 6 During normal operation of the system, the boiler 6 contains a quantity of the liquid fraction of high boiling point, and the pipe 13 projects above 10 ( the normal level of liquid in the boiler 6. Below the bottom of the boiler 6 a tubular carrier member 14 provides connection to the opening 12 The outer side of the carrier 14 is provided with heat-exchanging ele 10 ' ments 15 forming extensions from the carrier 14 and comprising apertures arranged in staggered positions 16 relatively to one another The carrier 14 is also provided at its inner side with heat-exchanging elements 11 ( forming extensions 17 having apertures 18. The extensions 15 are surrounded by a wall 19 of heat-insulating material and openings are provided leading from the space at the outer side of the carrier 14 to a conduit 115 22 A further opening 21 provides connection from the space at the inner side of the carrier 14 to an outlet pipe 23 The annular space 7 is connected to the space at the outer side of the carrier 14 12 C British Patent Specification No 17552/54 (Serial No 756,892) describes and claims a rectifying column

for fractionating a gasmixture and comprising an evaporator having a boiler and a heat-exchanger a first 125 part of which is located inside the boiler for supplying thermal energy to the fraction of high boiling point and a second part of which is located outside the boiler for 784,747 through the pipe 28 is constant The smaller the quantity of air supplied to the column; the smaller will be the quantity of vapour removed from the boiler The air to be fractionated is delivered to the column and 70 the fractions are drawn off from the system in accordance with the thermal energy withdrawn from the column by the gas refrigerator. Figure 3 shows one form of gas refrigera 75 tor suitable for use in a system according to the invention. The gas refrigerator comprises a cylinder in which a displacer 31 and a piston 32 are adapted to reciprocate with a substan 80 tially constant phase difference The displacer 31 is coupled by means of a connecting-rod mechanism 33 with a crank 34 of a crankshaft 35 and the piston 32 is coupled by way of a connecting-rod 85 mechanism 36 with two other cranks 37 of the crankshaft 35 Owing to the movement of the _displacer 31 the volume of the freezing space 38 is varied This space communicates with the cooled space 42, 90 through a freezer 39, a regenerator 40 and a cooler 41; the volume of the cooled space is varied by the movements of the displacer 31 and the piston 32 The refrigerator is driven by an electric motor 95 A medium to be cooled is supplied through port 43 to a freezing space 45 which is surrounded by a jacket 44 having heatinsulating properties In the space 45 the medium is cooled after which the cooled 100 medium leaves the refrigerator through ducts 46 and 47 Thus condensate may be supplied through the duct 46 as reflux to the column and the rest drawn off from the system through the duct 47 105


4336 4340.output

Law