4266 4270.output

* GB784673 (A)

Description: GB784673 (A) ? 1957-10-16

A method of producing printed circuit master drawings

Description of GB784673 (A)

PATENT SPECIFICATION Inventor: WILFRED HENRY FULLER C 4 p Date of application and filing Complete Specification: Feb 28, 1956. No 6114/56. Complete Specification Published: Oct 16, 1957. Indexatacceptance:-Classes 37, T 2; 98 ( 2), M; 100 ( 2), LA 6 A; and 146 ( 2), J 2 A 1 I. International Classification:-B 44 b G 03 f G 09 b H Oib. COMPLETE SPECIFICATION A method of Producing Printed Circuit Master Drawings We, STANDARD TELEPHONES AND CABLES LIMITED, a British Company, of Connaught House, 63, Aldwych, London, W C 2, England, 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 method of producing printed circuit master drawings. The first step in the production of printed circuits from copper-clad laminated insulating boards is the preparation of a master circuit pattern drawing either to actual size or several times actual size. Essential requirements of such master drawings are close dimensional tolerances, clear definition of line edges, and good contrast for photographic purposes. According to the invention there is provided a method of producing a printed circuit master drawing from scraper board consisting of a base board covered with a white layer which is in turn covered with a black layer comprising removal of portions of the black layer corresponding to a required circuit or its complement. An embodiment of the invention will now be described with reference to the accompanying drawings, in which: Fig 1 is a master drawing of a

circuit pattern in a "negative" form. Fig 2 is a master drawing of the circuit pattern of Fig 1, but in "positive" form. Fig 3 is a master drawing of a circuit pattern in a "positive" form. Referring to Fig 1, the circuit pattern of the printed circuit master drawing is engraved on "scraper board", which consists of a soft pulp-board backing on which is coated a layer of pure while china clay and chalk to a thickness of O 020 "-0 040 ", which is in turn over-coated with a very thin layer of black ink Corresponding to the desired conductor pattern, the black surface 1 is scraped away to expose the white clay as at 2, the lPrice 3 s 6 d l pattern being represented by white lines on a black ground, in a "negative" form. The contrast between the white clay base and the black surface makes the pattern ex 50 ceptionally suitable for process photography. Due to the fine granular structure of the white clay base, lines with clear cut edges are possible using gauged engraving tools to scrape away the black surface The use of gauged 55 tools allows very close dimensional tolerances, and makes possible the drawing of the full width of a conductor line in one operation This is particularly useful when the master drawing is prepared several times 60 actual size, when a conductor width may be substantial. If a printed circuit corresponding to the circuit pattern shown in Fig 1 is to be produced by photo-engraving, the next step com 65 prises the production to actual size of a reverse pattern photographic transparency from the master drawing which may be prepared actual size or several times actual size. An original pattern photographic transpar 70 ency is obtained from this reverse pattern transparency and which hats the conductor pattern shown as transparent lines between opaque areas This original pattern transparency is used to make a contact print on a 75 copper-clad laminate coated with a photographic emulsion The transparency is placed in contact with the coated surface and exposed to light After the exposure, the laminate is immersed in a suitable photo 80 graphic developer which dissolves the unexposed unprinted portion of the emulsion. This leaves the light-hardened emulsion as an acid resistant pattern conforming to the desired circuit pattern The laminate is then 85 placed in an etching solution which removes all the copper that is not protected by the acid-resistant emulsion. If the screen printing method is used, a reverse pattern photographic transparency of 90 the master drawing is produced as before. This transparency is used to produce a sten1-, 1 '1 784,673 cil which is placed on to a silk or metal screen The screen and stencil are placed on a copper-clad laminate and an acid-resistant liquid is

spread over the stencil The liquid is forced through the stencil and deposited on the surface of the laminate in a pattern corresponding to the required circuit pattern. The laminate is then etched as already described. A master circuit pattern drawing may be prepared on scraper board in a positive form, as shown in Fig 2, in which case the black surface is scraped away to leave the circuit pattern as black lines such as 3 on a white ground 4 Production by the photo-engraving method of a printed circuit from this master drawing requires only a reverse pattern photographic transparency which is used to contact-print the laminate as already described The screen-printing method requires a reverse pattern transparency from which is obtained an original pattern photographic transparency This transparency is used to produce a stencil as already described. Printed circuits obtained from master drawings shown in either Fig 1 or Fig 2 involve a technique in which a comparatively large area of copper is etched away This technique may be referred to as a "normal" system Another technique which may be referred to as a "minimum etch" system is one whereby thin lines of copper are etched away to provide insulation by separation between comparatively large areas of copper This is shown in Fig 3, which is a master drawing on scraper board in a "positive" form, in which the clay base is exposed as at 5 corresponding to the separation required The advantage of this technique is-in the small area of copper which has to be etched off the laminate, but the technique can only be used in circuit arrangements where the electrical characteristics permit of large and indiscriminate additional capacities. For the photo-engraving method according to this "minimum-etch" technique, only a reverse pattern transparency is required for the contact printing of the copper-clad laminate subsequent steps being as already described For the screen printing method an original pattern photograhic transparency must be obtained from the reverse pattern transparency This original pattern transSS parency is used to produce a stencil as already described.

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

* GB784674 (A)

Description: GB784674 (A) ? 1957-10-16

Mending plug for tubeless tyres


PATENT SPECIFICATION 784,674 Date of Application and filing Complete Specification: March 12, 1956. No 7581/56. Application made in United States of America on April 29, 1955. Complete Specification Published: Oct 16, 1957. Index at acceptance:-Class 144 ( 1)q B 1 C. International Classification:-B 62 g O COMPLETE SPECIFICATION Mending Plug for Tubeless Tyres We, SALESCASTER INCORPORATED, a Company Incorporated under the Laws of the State of New York in the United States of America, of 71-09 Austin Street, Forest Hills, New York, 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 means for plugging leak orifices in tubeless tyres. Since the tubeless tyres themselves provide the airtight casing, they must be kept hermetically closed to prevent deflation and the mending of holes through the treads of such tyres presents a problem substantially different from that of patching an inner tube. For practical reasons it is desirable to have repair means for the purpose which are effective and are at the same time easily employed without the need for special skill. Minute perforations which may cause slow leaks may be stopped by the insertion of a well-known latex compound which will set and close the perforation But larger punctures through the tyre tread, such as are caused by nails or the like, usually require the insertion of a plug to close the perforation. It is customary to employ for this purpose a hollow rubber cylindrical plug which is pointed and closed at one end and which is inserted into the puncture by means of a tool which is in the nature of a small rod

that is entered into the axial bore of the plug and presses the pointed end into the opening and through the tread until the pointed end protrudes into the air cavity The tool is then withdrawn and the resiliency of the tyre tightly compresses the plug and forms an airtight seal Usually a latex compound is applied in the hole-and about the plug to create an effective adhesion of the plug to the wall of the opening and also to seal any lPrice 3 1 small irregularities in the wall of the puncture The plug is substantially the same resiliency, hardness and consistency as the tread and the protruding end of the plug readily wears down to the surrounding face 50 of the tread and the amalgamation is complete and the repair plug becomes virtually invisible. However, the pressure of the end of the tool during the insertion of the plug is axi 55 ally on the inside of the point with the result that frequently the point-is ruptured and the plug becomes a tubular conduit for leakage of air When this occurs it is difficult and oftentimes impossible to extract the ruptured 60 plug and the tyre has to be taken to a shop equipped for the purpose for repair. To minimize the likelihood of this it has been the practice to terminate the tool receiving bore in the plugs a substantial distance 65 from the point This leaves an unsupported pointed end which is easily deflected during the insertion and sometimes bends so as to make further insertion impossible. The tyres have a plurality of plies of rein 70 forcing fabric moulded within their body so as to leave a rubber inner liner and a puncture is apt to rupture the fabric and leave the ends of the broken yarn or cord protruding into the hole resulting from the punc 75 ture The insertion of the mending plug tends to carry these broken ends inwardly and if they are of sufficient length they will protrude into the hollow interior of the tube. In such case air is apt to follow the cords by 80 capillarity and slow leakage is apt to result. The plugs of known construction have had no means for preventing this. The principal object of the present invention is to eliminate these defects in such 85 plugs More specifically it is an object to relieve the point from pressure during the insertion and at the same time to reinforce the point so as to, keep it axially aligned with the body or shank of the plug Another ob 9 G 784,674 ject is to provide effective means for preventing the escape of air by capillarity Other objects and advantages of the invention will appear as the description proceeds. The invention contemplates the provision of a reinforced internal shoulder at the beginning of the tapered or pointed end of the plug which will receive the pressure of the tool and which will allow the

end of the tool to extend into the point and keep it in alignment In this way the bore can extend well down into the point without any danger of rupture. For example, in a form of the invention which has proven commercially satisfactory, the bore in the pointed end is of less diameter than that in the cylindrical body or shank of the plug, thereby forming a shoulder which may be abruptly transverse to the axis or which may be tapered and conical. An annulus in the form of a flat or conical washer is disposed on the shoulder during the moulding operation and the tool is correspondingly shouldered so that the washer receives the pressure of the shoulder on the tool The extreme end of the tool is reduced in diameter so as to extend through the washer to the bottom of the bore in the pointed end This bore may be extended to within wall thickness of the external pointed end. While metal is at present preferred for the washers, it will be understood that other sufficiently strong materials, such as certain plastics, may be employed. It is within the contemplation of the invention to provide a pressure receiving annulus by means other than a transverse washer disposed on a shoulder at the meeting of the bores in the body or shank and pointed end. For example, it is contemplated that an insert of metal or the like may be fitted into the pointed end the rear end of which will provide a pressure receiving shoulder and which will constitute a reinforcing liner for the point. The invention also contemplates means for sealing the space about the plug where it emerges through the interior liner of the tyre, against the escape of air by capillarity. For this purpose the invention comprises an integral collar or sealing ring on the plug at or near the base of the pointed end which overlaps the inner wall of the tyre around the joint and is brought into contiguous sealing relation therewith by the withdrawal of the inserting tool, the latex compound about the joint effecting an hermetic union between the inner face of the liner and the contiguous face of the collar. The embodiments of the invention illustrated in the accompanying drawings will now be described. Fig 1 is a section of the tread portion of a tubeless tyre with a puncture closing plug embodying the invention disposed therein; Fig 2 is an enlarged fragmentary section through a tyre tread and a mending plug with the inserting tool therein and shown at an incomplete stage of insertion of the plug: 70 Fig 3 is an enlarged axial section of one form in which the invention may be embodied and showing the inserting

tool in place; Fig 4 is a rear end view of the same; 75 Fig 5 is a section similar to Fig 3 of a modified form of the invention; Fig 6 is a detail of the end of a tool for inserting the plug shown in Fig 5: Fig 7 is a section of the end of a plug 80 showing another modified form of the invention: Fig 8 is a detail of the end of a tool for inserting the plug shown in Fig 7: Fig 9 is a plan of a modified form of pres 85 sure receiving annulus of Fi- 7: Fig 10 is a sectional detail of a modified form of pressure receiving annulus and reinforcing liner for the pointed end of the plug, and 90 Fig 11 is a sectional detail of another modification of the type shown in Fig 5. The plug 1 which is shown in a tread section 2 of a tubeless tyre in Fig 1 is the same as that shown in Figs 2 and 3 and will now 95 be described It is understood that the plugs are ordinarily formed by moulding in a sectional mould which in the form of Fig 3 will part at the juncture of the cylindrical and conical portions of the plug A cylindrical 100 core equivalent to the inserted portion of the tool shown in Fig 3 produces the bore in the moulded plug and the washer set on the shoulder of the core is somewhat larger than the bore in the plug body and hence is 105 moulded into the wall of the bore. The plug l has an axially hollow cylindrical body or shank portion 3, the outside diameter of which is substantially uniform throughout its length, and a closed pointed 110 extension or top end 4 The axial bore of the shank is of substantially uniform diameter, and the extension has an axial bore of smaller diameter than that of the shank forming a coaxial continuation thereof and 115 thereby forming a shoulder on which the stamped flat metal pressure receiving annulus or washer 5 is seated coaxially with the bores The bore in the pointed end extends close to the external point, the rubber at the 120 tip end being no more than average wall thickness Along the external surface of the cylindrical body 3 are spaced circumferential ribs 6 such as are customarily used on plugs to enhance the sealing action of the plug 125 As shown in this embodiment the plug has a circumferential collar or sealing ring 6 a formed substantially at the base of the pointed end 4 and having its surface remote from the end 4 in a plane normal to the axis 130 784,674 of the plug, the surface facing the end 4 being tapered so that the collar is substantially frusto-conical in shape This collar is for the purpose of effecting a seal about the inner end of the hole as above mentioned and as will presently be further described. The inserting tool 7 has a rod portion 8 which terminates in a reduced end 9 of a size to pass through the hole in the washer 5 and fit in

the bore in the pointed end and of a length to reach substantially to the bottom of the bore in the pointed end when the shoulder formed by the reduced end bears against the washer 5 The section 8 is shown as of the same length as the body 3 but this is incidental, the requirement being that the shoulder engages the washer without the handle compressing the plug. It will be clear that the tool will hold the plug rigid during the insertion and that the pressure will be applied on the washer, thereby eliminating the danger of forcing the tool through the pointed end The tool will hold the plug distended until it is withdrawn, when the resilience of the tyre will compress the hollow plug throughout that portion contained within the tyre body The protruding ends will remain expanded as shown in Fig. 1 and the outer end, as stated, will soon be worn off. The ring 6 a will be folded down during the insertion of the plug, as shown in Fig 2, and will expand to its normal shape as it emerges into the air cavity of the tyre. The friction of the portion 8 of the tool 7 on the inner wall of the plug as the tool is withdrawn will draw the plug out so as to cause the normal face of the ring 6 a to bear tightly against the inner face of the rubber liner of the tyre The compound which is inserted in the puncture has a latex base and it will coat the two contiguous faces and effect sealing union therebetween, as shown in Fig 1. Fig 5 shows a different form of pressure receiving and point reinforcing member Instead of the flat washer 5, a stamped conical metallic liner 10 is moulded into the pointed end, the bore of which is contiguous with and tapers from the bore of the shank The metallic liner may be open ended as shown in Fig 11 This type of plug calls for a tool 11 which is shouldered to bear against the annular end of the liner 10 and is pointed beyond the shoulder to fit into the conical liner Incidentally this plug does not have a sealing ring 6 a and a different form of circumferential rib is shown in this construction, namely, one that is frusto-conical so as to function more in the nature of barbs and oppose withdrawal of the plug. The plug of which the end portion is shown in Fig 7 is like that shown in Fig 2 except for the omission of a sealing ring and differs from the form shown in Fig 3 in that the shoulder is conical and hence calls for a tool 12 such as shown in Fig 8 The stamped washer 13 has its edge scalloped, thereby forming radial extensions 13 a as shown in Fig 9, to facilitate its being formed to a 70 frusto-conical shape In this case the ribs are shown as closely spaced circumferential corrugations. Instead of stamped pressure receiving members as shown in Figs 3, 5 and 7, the 75 member may, be a cast liner such as the member 14 shown

in Fig 10. To avoid the necessity of exact conformance of the end of the tool 11 to the conical liner 10, the tip end of the liner may be re 80 moved, as shown in Fig 11 Thus there will be assured the engagement of the shoulder of the tool against the annular base of the liner and of the conical end of the tool withIt is obvious that still other modifications 85 in the liner during the inserting operation. may be made in the constructions shown in the drawings and above particularly described within the scope of the invention as defined in the following claims 90


* GB784675 (A)

Description: GB784675 (A) ? 1957-10-16

Improvements in and relating to slipper foot protectors


PATENT SPECIFICATION 784,675 ____ O Date of Application and filing Complete Specification: March 27, 1956 No 9 Application made in United States of America on March 31, 1955. - / Complete Specification Published: Oct 16, 1957. Index at acceptance:-Class 17 ( 2), B( 3 C:80:9 A). International Classification:-A 43 b. COMPLETE SPECIFICATION Improvements in and relating to Slipper Foot Protectors We, THE SCHOLL MANUFACTURING COMPANY LIMITED, a Company Incorporated under the Laws of Great Britain, of 190, St. John Street, London, E C 1, England, 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 improvements in a foot protector, and more particularly to a foot protector in the form of a slipper. In the past, many and various human foot protecting devices have been provided to eliminate the adverse effects of rubbing of the foot relatively to the shoe or vice versa particularly against the sides, bottom, and heel of the foot Such devices, however, were frequently attached to the shoe or other article of footwear and in other cases were worn on the human foot, but such devices could only be worn within an article of footwear Frequently, more than one device was necessary for each foot to eliminate the chafing action of rubbing with some particular article of footwear due to the fact that freedom of movement of the foot relatively to the shoe was more pronounced in one part of the footwear than in other parts thereof. In addition, such known devices had only the one function and could only be used for the single purpose that is to say worn on the foot, or disposed in the footwear. The main object of the present invention is to provide a slipper foot protector which may be worn within a shoe or other article of footwear, or may be worn without other footwear such as shoes in the manner of a house slipper A further object of the invention is to provide a foot protector in the form of a thin light weight slipper capable of fitting comfortably within a shoe or other article of footwear which may afford protection to the skin or hosiery of the user when worn as a house slipper without the article of footwear. According to the present invention a slipper foot protector comprises a sole portion of soft, resilient cushioning material, and a low cut upper of soft knitted fabric stitched to the sole portion 50 Preferably a heel guard or protector is secured to the fabric upper around the heel portion thereof, and one or both faces of the sole portion may be covered with a light weight smooth surfaced substance to elimi 55 nate any drag on the foot of the user or against the interior of a shoe The sole portion is preferably of foam latex which may have intercommunicating cells. In order that the invention may be more 60 clearly understood some embodiments thereof will now be described, by way of example, with reference to the accompanying drawing, in which:Fig 1 is a fragmentary perspective view of 65 a human foot encased in a slipper foot protector for a right foot; Fig 2 is a bottom plan view of the protector shown in Fig 1, the foot being omitted; Fig 3 is an enlarged transverse vertical 7, section through the protector on the line III-III of Fig 1, looking in the direction of the arrows; and, Fig 4

is a fragmentary vertical section view through a portion of a modified form of 76 protector. In the drawings like references are employed to designate the same or similar parts. In order to ensure an accurate fit, and to render the device more comfortable to the 80 user especially when worn within an article of footwear, the patterns for the device are cut for right and left feet The protector shown in Figs 1 and 2 is a protector for a right foot, and it will be understood that the 85 protector for the left foot is of the same general construction, but the pattern, particularly that for the sole portion, is shaped to suit the left foot. The protector comprises a sole portion 1, 90 596/56 1,9 k: A 784,675 best seen in Fig 3, which is preferably of foam latex of cellular construction having intercommunicating cells This material is very light in weight, comfortable to the foot, s t 5 and by virtue of the intercommunicating cells when used provides some ventilation due to the repeated application and releases of foot pressure against the device during walking. The outer surface, i e the underneath surface of the sole portion is covered with a thin smooth non-skid covering, such for example as silky finished fabric which eliminates any drag of the device against the insole of a shoe and renders it easy for the user to slip the foot in a protector into a shoe. A low cut upper 3 is attached to the sole portion in any suitable manner, such as for example by stitching 4 This upper 3 is preferably a one-piece construction and is preferably made of a soft elastic knit fabric such as a stocking fabric This upper is preferably made of twisted stretchable yarn so that it may fit feet of different sizes within a reasonable range, and be capable of contracting to provide a close fit around the foot which will feel comfortable to the wearer. The upper includes a portion 5 covering the toes of the user, a heel embracing part 6, with low cut side walls 7-7 connecting the toe and heel portions Where the upper is of elastic knit fabric, it may be easily stretched over the foot. Any suitable form of marginal finish 8 may be provided as by folding over the upper edge portion of the fabric Inside the folded margin 8 a thin strip 9 of rubber or equivalent elastic material is inserted as shown in Fig 3 to hold the device more firmly on the foot of a user. It is preferable in the heel portion of the upper to insert a heel protector or guard 10 (Figs 1 and 3) preferably made of thicker and stiffer material than the upper, but preferably flexible such as felt or foam rubber for example The heel guard 10 is shown secured to the upper only along the top edge of the guard, and in effect the guard depends from the upper and extends to a point just above the sole

portion The heel guard 10 may be provided with numerous perforations 11 for ventilative purposes, if so desired. Referring to Fig 4, this shows a modified construction, having the inside surface of the sole portion or cushioning member 1 also covered with a thin non-skid covering 12 such as a silky finish fabric similar to the cover 2 over the outer face of this cushioning member Either the inner or outer surface of the cushioning member may be provided wvith such a cover, or both faces may be so covered as shown in Fig 4. The device is of simple construction and may be easily slipped over the foot, and provides a comfortable cushioning relief to the bottom of the foot, provides adequate ventilation, and may readily be worn inside an article of footwear without discomfort to the user Alternatively, the device may be worn over the naked foot or over a foot encased in hosiery When the device is in position on 70 the foot, even when worn with a loose fitting article of footwear, no adverse effects from rubbing at any part of its surface will result. Chafing or blistering of the heel is also effectively prevented by the additional heel guard 75 At the same time, the cushioning effect of the foam latex sole portion gives the same benefits as a cushion insole disposed in the article of footwear Further, the device may be laundered whenever deemed necessary, is 80 very durable, and highly economical. When the user is in the house or home and removes his shoes or the like, the device may be utilized temporarily as a house slipper affording adequate covering for the foot, and 85 providing a cushioning element to walk upon.


* GB784676 (A)

Description: GB784676 (A) ? 1957-10-16

Improvements relating to dynamometers


COMPLETE SPECIFICATION Improvements relating to Dynarnometers We, SOCIETA PER AZIONI ASPERA, a Joint Stock Company organised under the laws of Italy, of 49 Corso Corsica, Turin, Italy, 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 dynamometers for measuring engine power, of the type in which the resisting torque applied to the engine shaft is brought about by a bladed member adapted to create a stream of fluid, such as air. Most known dynamometers of this type comprise one helical impeller rotatable in free air, or at the utmost protected by wire gauze or perforated sheet metal guards to prevent any accidental contact by the operator with the impeller. Dynamometers of this type set up a heavy draught and noise in the space where the engine to be tested is installed; moreover, when they are intended for measuring relatively high power, the impeller size becomes prohibitive. It is the purpose of this invention to provide a dynamometer of the aforessaid type which substantially avoids the above - mentioned drawbacks, and more particularly to provide a dynamometer in which the air stream set up by the bladed member does not give rise to undesirable disturbance in the space in which the dynamometer is installed. A further purpose of this invention is to provide a dynamometer adapted to operate on engines rotating in either sense. The invention will now be described with reference to the accompanying drawings, wherein: Fig. 1 is an elevation mounted in axial section of the dynamometer; Fig. 2 is an end view of the same, its end wall being partly broken away; Fig. 3 is a sectional view of a detail of Fig. 1 on an enlarged scale; Fig. 4 is a sectional view of a further detail of Fig. 1, also on an enlarged scale; Figs. 5 and 6 are diagrammatical sectional views respectively on lines V-V and VI-VI of Fig. 1 and showing the arrangement of the blades; Fig. 7 is a sectional view of the device for measuring the braking

torque; and Figs. 8, 9 and 10 are sectional views on lines VIIP--VIII of Fig. 7 in three different operative positions of the device. The dynamometer is carried by a shell 40 mounted on a foundation 41. The splined inlet shaft 6 of the dynamometer is rotatable in either direction and is coupled by a coupling of known type (not shown) with the shaft of the engine of which it is desired to measure the power. Devices 42 and 34 are provided for measuring the torque supplied by the engine and the number of revolutions of the input shaft 6, respectively. The shell 40 encloses end casings 40a, 40b housing a device for varying the pitch of the dynamometer blades, and a device for transmitting motion from the shaft 6 to the dynamometer shaft, both of which are described hereafter. The inlet shaft 6 is supported (Fig. 4) by ball bearings 44, 45 carried by a hollow hub 46a integral with a plate 46 which is secured to the end wall 40c of the shell 40 by means of bolts (not shown). The shaft 6 has keyed thereon a toothed wheel 7 meshing with a toothed wheel 8 fast with a hollow hub 8a carried by ball bearings 70, 71. The toothed wheels 7, 8 are easily replaceable by other wheels that differ in transmission ratio. The outer race rings of the bearings 70, 71 are carried by a rocking frame or cradle comprising plates 9a, 9b fast with an arm 9 (Fig. 2) and pivoted to the shaft 6 on both sides of the wheel 7. Within the hollow hub 8a (Fig. 4) a pair of axial grooves 8c, 8d are cut, in which coaxial dogs 47a, 47b extending from opposite ends of a block 47, are capable of displacement. The block 47 further carries a through pin 48 having its axis perpendicular to the axis of the dogs 47a 47b, the forked end 1 la of a shaft 11 being hinged to the pin 48. The other end of the shaft 11 is coupled by a cardan joint 48 (Figs. 1 and 3) to a hollow shaft 19 provided with an extension 19a in the shape of a sleeve coaxial with the shaft 19 and encircling the shaft 11. A drum 49 is secured to the shaft 19 and sleeve l9a. The cylindrical wall of the drum 49 has spindles 12a, 12b, 12c, 12d extending there through, a plurality of blades subdivided into four sets l3a, I3b, 13c, 13d being fast with these spindles; the axes of the blades of each set are situated in the same plane orthogonal to the shaft 19 and are staggered through the same angle. The blades of sets l3a, 13b are arranged to provide an approximately axial air flow directed oppositely to the air flow set

up by the blades 13c, 13d. According to the sense of rotation of the shaft 19, the axial flows set up by the four blade sets converge towards the brake centre or diverge. Assuming the shaft 19 is rotated in a direction to provide converging flows, the air flows set up collect in a central annular chamber 50, flow in the direction denoted by the arrow a (Fig. 1) to the foundation 41, then travel outwardly in opposite directions to the ends of the casing, whence they ascend in the direction denoted by the arrows b and back to the suction side of the four blade sets. Discs 14cm, 14b, 14c, 14d (Figs. 3, 5 and 6) are keyed to the end of spindles 12a and 12b, 12c, and 12d remote from the blades and carry concentric pins 51a, 51b, 51c, 51d which fit into annular grooves formed in the end of arms 15a, 15b, 15c, 15d The arms 15a and 15b are fast with a sleeve 52, and the arms 15c and 15d are fast with a sleeve 53. The sleeves 52 and 53 are connected together by means of rods 16 arranged approximately parallel with the shaft 19 and guided in holes bored in the arms 15b, 15c. The sleeves 52 and 53 are concurrently displaceable in an axial direction by means to be described hereafter. The pins 51a, 51b, Slc and 51d are seated in annular grooves formed in the end of arms 15a, 15b, 15c and 15d so that the concurrent axial displacement of the sleeves 52 and 53 rotates the spindles 12a and 12b carrying the blades 13a and 13b in one direction and the spindles 12c and 12d carrying the blades 13c and 13d in the opposite direction. Sjr adjusting the angular setting of the blades the delivery of the air flows set up by the blades, is varied, thereby adjusting the braking toroue applied to the motor the power of which is to be measured. Flow deflectors 27a, 27b, respectively are interposed between each pair of blade sets 13a, 135 and 13c, 13d and comprise flat discs (see Figs. 5 and 6) in which slots are provided to deflect the flow from a set of blades, for instance the blades 1 3a, in order to oppose through the said flow rotation of the other blade set, such as 13b; more particularly, the slots have their axes radially arranged with respect to the disc, their sides lying in planes inclined with respect to the disc axis. The slots are formed at each end and on their opposite sides with an inturned arcuated projection. For instance, the arcuate projection 27c in Fig. 5 is arranged to deflect the flow travelling through the slot along the arrow c in the direction d, when the blades 13a and 13b rotate in the direction denoted by the arrow c. When the blades 13a, 13b rotate in the direction denoted by the arrows f, the air flow set up by the blade set 13b directed along the arrow g

is deflected by arcuate projections 27a in the direction of the arrow h thereby opposing rotation of the blade set 13a. Similar considerations apply to the blades 13c and 13d. Axial displacement of the sleeves 52 and 53 is obtained by means of a peg 20 (Fig. 3) arranged with its axis perpendicular to the axis of the shaft 19 and extending through a slot 19b cut in that shaft. The peg 20 has fast therewith a rod 21 axially displaceable through the hollow shaft 19 and having a peg 54 extending therethrough perpendicular to the shaft, the peg 54 extending through a further slot l9c cut in the shaft 19. The peg 54 engages a sleeve 22 coupled by means of a thrust bearing 25 with an external sleeve 24 carrying a rack 24a engaged by a toothed wheel 23 keyed to a shaft 23a. The shaft 23a has keyed thereto a handwheel 26 (Fig. 2) and is carried by a boss on the fonvard wall of the shell. Operation of the handwheel 26 results, through the toothed wheel 23 and rack 24a, in an axial displacement of the sleeve 24 which is transmitted, through the thrust bearing 25, to the sleeve 22 and, through the peg 54, to the shaft 21 which axially displaces the sleeve 52, through the peg 20, and the sleeve 53, through the rods 16. The invention futher provides means for detecting the torque transmitted by the engine shaft to the shaft 6 and by the latter to the shaft 11. This means comprises the arm 9 fast with the plates 9a, 9b and acting on a measuring device shown in detail in Figs. 7 to 10. The end 9c of the arm 9 is of spherical shape and acts on a piston 31 slidable in a sleeve 65 which in turn is slidable in a sleeve 66. The sleeve 66 moves in a cylinder 32 fast with the shell 40. The cylinder 32 is provided with an end flange 32b connected by bolts 60 and nuts therefor to a top plate 63 provided with a cylindrical boss 63a movable in a hole 61b bored in a plate 61; the latter is provided with a tab 61a for attachment to the shell 40. A hole is bored in the cylindrical boss 63a in the plate 63, a small tube 64 being welded in this hole for the outlet of fluid contained in the top chamber 35 in the cylinder 32 to a pressure gauge 42. A peg 67 extends through the piston 31 and has its ends seated in shaped notches in the lower end of the sleeves 65 and 66. The piston 31 is formed with a reduced portion 311 having keyed thereto an arm 33 provided with an operating knob 33a resting on a bracket 2. The peg 67 bears in the in- operative condition of the piston on projections 32a extending inwardly from the wall of the cylinder 32. The notches in the sleeves 65, 66 have substantially vertical end edges and a top edge comprising two portions arranged at different levels merging into each other. More particularly, the top edge of the notch in the sleeve 65 comprises a portion 65ce at a higher level and a portion 65b at a

lower level, and the top edge of the notch in the sleeve 66 comprises a portion 66a at a higher level and a portion 66b at a lower level, the end vertical edges of the two notches being angularly in register, the portion 66a of the sleeve 66 being considerably longer than the portion 65a in the sleeve 65. In the position shown in Fig. 9 the piston 31 can rise to a limited extent denoted by a without carrying along either the sleeve 65 or the sleeve 66. When the peg 67 is moved to the position shown in Fig. 8 however the piston 31 on rising carries along the sleeve 65, and when the peg 67 is moved to the position shown in Fig. 10, the piston 31 on rising carries along both the sleeve 65 and the sleeve 66. Consequently, the same displacement of the piston 31 sets up different compressions in the chamber 35 depending upon whether the piston 31 is free or is coupled with the sleeve 65 or with both sleeves 65 and 66. With this device the measuring range of the dynamometer is varied to suit the power of engines varying very considerably in size. Moreover, the device is adapted to effect measurement on engines rotatable in either direction. In fact, on rotation in one direction to which there corresponds, for instance, rising of the arm 9, the piston 31 and any sleeve coupled therewith likewise tend to rise, the reaction being taken up by the plate 61. When the engine rotates in the opposite direction, the spherical portion 9c of the arm 9 tends to sink and abuts the bottom 32 of the cylinder, which is thereby lowered together with the cylinder, this being permitted by the slip coupling between the cylindrical boss 63a and hole in the plate 61. Reaction is then taken up by the bracket 2 fast with the brake shell, abutted by the piston through the arm 33. A further factor contributing in considerably reducing the size of the dynamometer resides in the possibility of replacing the toothed wheels 7 and 8 by other wheels differing in transmission ratio. Even with slow-speed engines the blades can then be rotated always approximately at their maximum rate, thereby constantly delivering the maximum braking effect. What we claim is : - 1. A dynamometer for measuring engine power output, characterised in that it comprises a multi-stage axial flow air compressor operating in a closed cycle. 2. A dynamometer as claimed in Claim 1, characterised in that flow deflectors (27a, 27b) are interposed between the various blade sets or stages (13a, 13b and 13c, 13d) of the axial compressor and are oppositely oriented to the flow deflectors in conventional air compressors, thereby impeding the air flow and lowering the efficiency of the compressors. 3. A dynamometer as claimed in Claim 1, characterised in that it

comprises means for varying the blade pitch. 4. A dynamometer as claimed in Claim 1, characterised in that the plurality of blades of the air compressor are subdivided into two sets at least in order to set up two oppositely directed air flows, these air flows being circulated through conduits in the machine shell (40). 5. A dynamometer as claimed in Claim 4, characterised in that the two blade sets are arranged to provide air flows directed from the shell ends towards the centre thereof, the air conduits in the shell comprising a pair of chambers arranged at the shell ends, a chamber (50) arranged at the shell middle between the two blade sets and a lower chamber in the brake foundation (41) connecting with the central chamber and end chambers. 6. A dynamometer as claimed in Claims 1 and 3, characterised in that the blades are secured to spindles (12a, 12b, 12c, 12d) radially arranged through the cylindrical wall of a drum (49) coaxial with the brake shaft (19) and rotatable therein, the means for varying the blade pitch comprising eccentric pins (51a, 51b, 51c, 51d) fast with the spindles, at least one sleeve (52, 53) slidable but nonrotatable on the shaft, radial arms (15a, 15b, 15c, 15a) carried by the sleeve, annular groove lengths coaxial with the sleeve cut in the ends of the arms and receiving the eccentric pins, and means for axially displacing the sleeve in order to vary the angular setting of the blades. 7. A dynamometer as claimed in Claim 6, characterised in that the pins (51a, 51b, 51c, 51d) are fitted into the grooves so as to set angularly the blades of one blade set in one direction and the blades of the other blade

* GB784677 (A)

Description: GB784677 (A) ? 1957-10-16

Improvements in or relating to heating boilers


PATENT SPECIFICATION Date of Application and filing Complete Specification: May 14, 1956.

Application made in Switzerland on March 28, 1956. Complete Specification Published: Oct 16, 1957. Index at acceptance:-Class 64 ( 1), N 1 DII(A:C 2 C). International Classification:-F 24 g. COMPLETE SPECIFICATION Improvements in or relating to Heating Boilers We, STUCKLIN & C 1 E, a Swiss Company, of Breisacherstrasse 43, Basle, Switzerland, 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 heating boiler comprising a front combustion chamber, a 1-0 rear heat exchange chamber having a flue gas inlet to receive flue gases from said combustion chamber and a flue gas outlet, and a plurality of pockets arranged in said heat exchange chamber and exposed to said flue gases and having closed lower and open upper ends to permit of a circulation of a liquid within the pockets by convection, said pockets being of wedge-shaped horizontal section and facing the combustion chamber with their larger ends, to form a pocket bank converging from said combustion chamber. An illustrative embodiment of the invention is shown on the accompanying drawing, in which:Fig 1 is a mainly sectional side view of a heating boiler; and Fig 2 is a horizontal sectional view taken on line II-II of Fig 1. The heating boiler shown in Figs 1 and 2 has a front combustion chamber 1 having a refractory brick lining and into which the flame tube of an oil burner 2 extends, and a heat exchange chamber 3 which lies behind the combustion chamber and has an oval outline together with the latter A partition 4 of refractory bricks is provided between these two chambers and is formed in its upper part with a flue gas opening 4 a The heat exchange chamber 3 contains pockets 5, which may be provided at their lower end with discharge taps and form a pocket bank converging from the partition 4 These pockets are wedge-shaped in horizontal section and face the combustion chamber with their rounded larger ends The spaces between lPrice 3/6 l adj acent pockets are of uniform width from the front to the rear The two chambers 1 and 3 are covered at the top by a cover plate 7, which is formed in its rear half with slots 7 a, registering with the pockets 5 in arrangement 50 and cross-sectional shape The pockets are welded at their upper edge portion into said slots Thus the cover plate and pockets form a single body, which is arranged so that the pockets 5 depend in the heat exchange cham 55 ber 3 and extend almost to the bottom of the same A closing wall 8 provided at the end of the pocket bank adjacent to the partition 4 is formed with slots corresponding to the large ends of the pockets 5 and is welded to 60 said pockets Arcuate lateral

external walls 9 and 10 and the side walls of the combustion and heat exchange chambers form crescentshaped water chambers 9 a and la, which communicate with a top water chamber 65 formed by the cover plate 7 and the coverlike top 11 of the boiler and extending throughout the area included by the two external walls 9 and 10 Outlet and inlet pipe connections 12 and 13, respectively are 70 provided at the rear end of the top 11 of the boiler The inlet pipe connection 13 is disposed somewhat below the outlet pipe connection and is continued at its inner end by a pipe 13 a, which extends through a transverse 75 wall I 4 a extending above the combustion chamber 1 throughout the width thereof. This transverse wall 14 a divides the top water chamber into a front part communicating with the front parts of the crescent-shaped 80 water chambers 9 a and 10 a and a rear part communicating with the rear parts of the crescent-shaped water chambers 9 a and la and with the upper ends of the pockets 5. The rear end of the heat exchange chamber 85 3 is formed by a rear wall 14, which is detachably arranged so that its removal provides a cleaning hole through which the pockets 5 can be conveniently cleaned on the outside owing to their special shape and 90 784,677 No 14883156. 784,677 arrangement. When the boiler is to be coal-fired and a door is replaced for the oil burner 2, the refractory brick lining of the combustion chamber 1 as well as the partition 4 are eliminated. In the operation of the boiler the returning colder water flows over that part of the cover plate 7 which forms the heating surface exposed to the highest radiation temperature. Thus condensation in the combustion chamber side by the cooled returning water is avoided From there the water flows to the crescent-shaped water chambers 9 a and 10 a, where it subsides and mixes with the hotter water therein From these chambers the water flows to the rear part of the pockets 5, subsides in the same and rises in the front part of the pockets, near the combustion chamber It is thus apparent that the cooled returning water is preheated before it enters the pockets, whose external heating surfaces are contacted by the cooled flue gases, whereby condensation is prevented The heated water flows then in the usual manner to the outlet pipe connection 12. Forming a converging pocket bank the pockets 5 of wedge-shaped cross-section provide an optimum overall heating surface within an extremely small space After the rear wall 14 has been removed they can be cleaned on the outside through a relatively narrow cleaning hole The streamlined shape of the pockets provides for an aerodynamical flow of the flue gases without impact and turbulence, whereby

pulsation at the beginning of the operation of the oil burner is avoided The flue gases entering the heat exchange chamber at the upper part of the pockets impinge on heating surfaces on which lime and mud will not deposit Finally, the manufacturing costs of the boiler are less than those of some boilers of the same capacity and of different design.


4266 4270.output

Food