IRS POINT MACHINEIRS POINT MACHINE

IRS POINT MACHINE is rotary locking type point IRS POINT MACHINE is rotary locking type point machine and designed to comply with machine and designed to comply with IRS IRS specification S-24/2000 and RDSO specification S-24/2000 and RDSO Dr.No.S10.800. Dr.No.S10.800. it is designed operate all type of points /switches.it is designed operate all type of points /switches.It is available in two model low stroke (143mm) It is available in two model low stroke (143mm) and high stroke (220mm)and high stroke (220mm)

It is non-trailable type point machineIt is non-trailable type point machine

SrSrNobNob

Description Description remarkremark

11 TypeType D.C. high thrust (stroke 143mm)D.C. high thrust (stroke 143mm)

22 Other model Other model High stroke 220mmHigh stroke 220mm

33 Type of LockingType of Locking Rotary typeRotary type

44 Locking of switchesLocking of switches Independent (two lock slides)Independent (two lock slides)

55 Arrangement for Locking of switchesArrangement for Locking of switches Indirect through ground connections Indirect through ground connections (rods) in side machine(rods) in side machine

66 Thrust Thrust 700 Kg700 Kg

77 Over load protectionOver load protection Friction clutch self adjustableFriction clutch self adjustable

88 Snubbing Snubbing MechanicalMechanical

99 Locking of throwLocking of throw Available Available

1010 Number of control contactNumber of control contact 2+2 2+2

1111 Number of detection contactNumber of detection contact 2+22+2

1212 Greasing nippleGreasing nipple 1111

1313 weightweight 220 Kg220 Kg

1414 packingpacking Wooden skeleton Wooden skeleton

1515 Number of ground connectionsNumber of ground connections Five (02 lock+ 02 detection + 01 Five (02 lock+ 02 detection + 01 through)through)

Important feature Important feature

General Features of point machine General Features of point machine

The basic design of point machine generally The basic design of point machine generally comprises ofcomprises of

Cast iron casing and cover with locking Cast iron casing and cover with locking arrangement arrangement

MotorMotor Reduction gearReduction gear Crank handle mechanismCrank handle mechanism Friction clutchFriction clutch Contact assembly with spring loaded rollers and Contact assembly with spring loaded rollers and

Detection slides Detection slides Rotary to linear conversion mechanismRotary to linear conversion mechanism Locking and throw assemblyLocking and throw assembly

Cast iron caseCast iron case

accommodates all the parts of point accommodates all the parts of point machinemachine

is made of cast iron and designed to fix all is made of cast iron and designed to fix all parts at required place.parts at required place.

provide access to/ slots for different lock provide access to/ slots for different lock and detection slides and detection slides

facilitate fixing of machine on sleepersfacilitate fixing of machine on sleepersProvides an arrangement to drain out Provides an arrangement to drain out

water/ oil in bottom of casting.water/ oil in bottom of casting.Provides cable entry.Provides cable entry.

Cast iron caseCast iron case

COVER OF POINT MACHINECOVER OF POINT MACHINE

Made up of thick iron sheet and fixed on cast iron Made up of thick iron sheet and fixed on cast iron casting (case) casting (case)

Contain lock ( S&T maintainer's lock) on inner Contain lock ( S&T maintainer's lock) on inner side surface to lock it with cast iron casting side surface to lock it with cast iron casting (case). (case).

Secure all the parts of machine in weather proof Secure all the parts of machine in weather proof environment and prevents un-authorosed environment and prevents un-authorosed interference.interference.

Provides access only to nominated (ward Provides access only to nominated (ward &feather) crank handle insertion.&feather) crank handle insertion.

All the apertures for keys and crank handle are All the apertures for keys and crank handle are secured by flaps secured by flaps

All flaps has a locking arrangement All flaps has a locking arrangement

COVER OF POINT MACHINECOVER OF POINT MACHINE

Cover top view Cover inner view

lock

FlapFor Crank handle

FlapForCoverkey

Flap for crank handle key

MOTORMOTOR

DC motor DC motor IRS: S 37 Motors for Electric IRS: S 37 Motors for Electric Point Machine.Point Machine.

shall comply with the requirements shall comply with the requirements of IRS: S 37 'Motor for Electric Point of IRS: S 37 'Motor for Electric Point machine.machine.

Motor comprises ofMotor comprises of1.1. crank handle cutout crank handle cutout

contact contact assembly,assembly,2.2. DC motor DC motor 3.3. reduction gearreduction gear

CRANK HANDLE AND CRANK CRANK HANDLE AND CRANK HANDLE MECHANISMHANDLE MECHANISM

It allows Manual operation (without It allows Manual operation (without power) of point power) of point

It require in case of failures of point/ It require in case of failures of point/ point machine OR for the purpose of point machine OR for the purpose of maintenance of point machine.maintenance of point machine.

It contain It contain 1.1. CRANK HANDLE AND KEYCRANK HANDLE AND KEY

2.2. CRANK HANDLE CUTOUT CONTACT ASSEMBLYCRANK HANDLE CUTOUT CONTACT ASSEMBLY

CRANK HANDLECRANK HANDLE

This apparatus is used for This apparatus is used for manual operation of point manual operation of point machinemachineIt is a “Z” shape structure It is a “Z” shape structure made of steel pipe and has made of steel pipe and has wooden handle on one end wooden handle on one end to have better gripe. to have better gripe. Wards &feathers are Wards &feathers are welded on other end of pipewelded on other end of pipefacilitates coding (insertion facilitates coding (insertion of only to nominated crank of only to nominated crank handle).handle).A stud is intrude in the A stud is intrude in the pipe, it get engage in pipe, it get engage in forked shaft of motor forked shaft of motor

Crank handle

Woodenhandle

Ward &feather

CRANK HANDLE CUTOUT CRANK HANDLE CUTOUT CONTACT ASSEMBLYCONTACT ASSEMBLY

It disallows simultaneous power and manual It disallows simultaneous power and manual operation of point machine to protect staff operation of point machine to protect staff performing crank handling. performing crank handling.

Ordinarily crank handle can not be inserted in Ordinarily crank handle can not be inserted in machinemachine

Turing of crank handle key permits/ allows insertion Turing of crank handle key permits/ allows insertion of crank handle in the machine.of crank handle in the machine.

Turning of crank handle key isolates the negative Turning of crank handle key isolates the negative power path of motor.power path of motor.

It comprise of It comprise of

1.1. Crank handle cutout contactsCrank handle cutout contacts

2.2. flap cover plateflap cover plate

3.3. Crank handle keyCrank handle key

Crank handle cutout contactsCrank handle cutout contacts

There are two sets of There are two sets of contactcontact

These contacts are These contacts are wired in negative path wired in negative path of power supply to of power supply to motor. motor.

Contacts break / open Contacts break / open with insertion and with insertion and turning of crank turning of crank handle key handle key

Makes when crank Makes when crank handle key is taken handle key is taken out.out.

1 1

2

Crank handle contact closed & Flap in front of shaft

Crank handle contact open &Flap displaced & shaft visible

Flap cover plate & keyFlap cover plate & key

controls the entry of crank handle in controls the entry of crank handle in the machine for manual operationthe machine for manual operation

metal flaps attached to a lock metal flaps attached to a lock hangs/ placed in front of motor shaft hangs/ placed in front of motor shaft

at the entry point of crank handle.at the entry point of crank handle. flap cover plate is displaced by flap cover plate is displaced by

means of a crank handle key means of a crank handle key The insertion and turning of crank The insertion and turning of crank

handle key handle key displace the flap cover plate to allow displace the flap cover plate to allow

insertion of crank handle insertion of crank handle open crank handle cutout contacts. open crank handle cutout contacts.

Removal of the crank handle key Removal of the crank handle key replaces flap cover in front of motor replaces flap cover in front of motor

shaft shaft makes the crank handle contact.makes the crank handle contact.

Crank handle key

Flap cover plate and crank handle key

Crank handle insertion

Insertion & turning of key displaces flap Cover plate

Flap cover plate in front of crank handle Entry & shaft of motor

DC motorDC motor

is a series split field DC motoris a series split field DC motor Is design to work on 110volt DCIs design to work on 110volt DC Is a series motor to meet high initial torque Is a series motor to meet high initial torque

requirementrequirement Is split field so that motor can be rotated in both Is split field so that motor can be rotated in both

direction direction contains four field windings and two windings are contains four field windings and two windings are

connected in series to form a set of winding.connected in series to form a set of winding. Use carbon brushes Use carbon brushes

SrSrNobNob Description Description RemarksRemarks

11 TypeType D.C. Series split fieldD.C. Series split field

22 Operating voltage Operating voltage 110 Volt DC (60 volt mini)110 Volt DC (60 volt mini)

33 currentcurrent 2 to 2.5 Amps2 to 2.5 Amps

44 Thrust Thrust 700 Kg700 Kg

55 PowerPower 0.48KWt0.48KWt

66Reduction ratio (in side Reduction ratio (in side motor)motor) 20.8 :120.8 :1

77 AC immunityAC immunity 160 , 300, 400 volts160 , 300, 400 volts

88 Power supply terminalsPower supply terminals 0303

99Insulation grade of Insulation grade of windingswindings More than 10 M OhmsMore than 10 M Ohms

Technical parameters of motorTechnical parameters of motor

DC MOTOR main partsDC MOTOR main parts

Armature and commutatorArmature and commutatorField winding Field winding Carbon brushes Carbon brushes Motor body Motor body Groove for crank handle Groove for crank handle

DC motorDC motor

Pinion

Rec

Reduction Gear

Power Terminal

Commutator & brush

Armature and commutatorArmature and commutator

Function of armature Function of armature To carry current crossing To carry current crossing

the field thus creating the field thus creating shaft toqueshaft toque

To generate an To generate an electromotive forceelectromotive force

Function of Commutator Function of Commutator Reverse the current in Reverse the current in

moving coil of motor’s moving coil of motor’s armature and generate a armature and generate a steady rotating force steady rotating force (torque)(torque)

Field winding Field winding

The function of the field The function of the field winding create magnetic winding create magnetic field for armaturefield for armature

motor contains four field motor contains four field windingswindings

two windings are two windings are connected in series to form connected in series to form a set of winding.a set of winding.

one set of winding rotate one set of winding rotate motor clockwise and other motor clockwise and other set of winding rotate set of winding rotate motor anticlockwise motor anticlockwise directiondirection

Carbon brushes Carbon brushes

Brush is rectangular carbon Brush is rectangular carbon block and spring loaded in block and spring loaded in holder holder Brush provides the electric Brush provides the electric connectivity between field connectivity between field windings and rotating windings and rotating commutator commutator the holders should be mounted the holders should be mounted a maximum of .125" above the a maximum of .125" above the contact surface.contact surface.Proper functioning of the holder Proper functioning of the holder depend upon, depend upon,

Inside holder dimensionsInside holder dimensions equally Holder spacing equally Holder spacing Holder angle (20 to 30 deg.)Holder angle (20 to 30 deg.) Holder heightHolder height Spring force (4.0-6.0 PSI)Spring force (4.0-6.0 PSI) Electrical connectionsElectrical connections

Carbon brush

Reduction gearReduction gear

It is trail of gears which provides reduction ratio 20.8:1It is trail of gears which provides reduction ratio 20.8:1

Number of teeth on driverNumber of teeth on driver Reduction Ratio = -------------------------------------Reduction Ratio = ------------------------------------- Number of teeth on driveNumber of teeth on drive Reduction ratio provides a torque-speed conversion from a Reduction ratio provides a torque-speed conversion from a

higher speed motor to a slower but more forceful output.higher speed motor to a slower but more forceful output. MotorMotor rotate at very high speed and Load can not be rotate at very high speed and Load can not be

directly placed on motor shaft.directly placed on motor shaft. Appropriate reduction gear ratio is used Appropriate reduction gear ratio is used

to get require mechanical advantage/ thrustto get require mechanical advantage/ thrust to syncronised various functionsto syncronised various functions to change direction of rotation to change direction of rotation to get desire power as to get desire power as

Reduction GearReduction Gear

pinionpinion

Hover flow pipe

Oil entry

Friction ClutchFriction Clutch

Friction clutch is an Friction clutch is an assembly of spring assembly of spring loaded Gear, shaft and loaded Gear, shaft and disks which are placed disks which are placed between motor and between motor and Load (point throw / Load (point throw / transmission assembly).transmission assembly).

Functions of friction Functions of friction clutch areclutch are To protect the motor To protect the motor

from overloadfrom overload To achieve mechanical To achieve mechanical

(dynamic) snubbing (dynamic) snubbing To follow the sequence To follow the sequence

of point operation.of point operation.

Transmission assemblyTransmission assembly

pinion

Lock segment

Drive disc

Gear

rim

slip

rim

Lift out

disc

Control

disc

Feature of friction clutchFeature of friction clutchThe friction clutch designed toThe friction clutch designed toextend stroke (force) from motor to load (point) extend stroke (force) from motor to load (point)

if load is within Specified limit (700 Kg)if load is within Specified limit (700 Kg)de-clutch (separate) motor and Load (point) if de-clutch (separate) motor and Load (point) if

load is more Specified limit (700 Kg).load is more Specified limit (700 Kg).De-clutching of friction clutch can be adjusted to De-clutching of friction clutch can be adjusted to

suite Specified limit of load (700 Kg) by suite Specified limit of load (700 Kg) by loosening Or tightening spring.loosening Or tightening spring.

Friction clutch require / needs an adjustment if Friction clutch require / needs an adjustment if slipping current /obstruction current shall not be more slipping current /obstruction current shall not be more

than 1.6 to 2 times of normal working currentthan 1.6 to 2 times of normal working currentdifference between normal working current and difference between normal working current and

slipping current /obstruction current is less than 0.5 slipping current /obstruction current is less than 0.5 Amps.Amps.

The friction clutch shall adjusted in workshop only (not The friction clutch shall adjusted in workshop only (not at site).at site).

Parts of friction clutchParts of friction clutch

Friction clutch comprises ofFriction clutch comprises of Control discControl disc Lift out discLift out disc Drive discDrive disc Gear rim and slip rimGear rim and slip rim Shoe expansion (locking Shoe expansion (locking

plate) plate) Helical spring Helical spring

Sequence of rotation of gear &discSequence of rotation of gear &disc

How different gear and disc rotate in side friction How different gear and disc rotate in side friction clutch clutch

Pinion of motor rotatesPinion of motor rotates

Gear rim, then Gear rim rotates Gear rim, then Gear rim rotates

slip rim then slip rim rotates slip rim then slip rim rotates

shoe expansion, then shoe shoe expansion, then shoe rotates rotates

lift out disc and lift out disc and

drive disc, then d.disc rotatedrive disc, then d.disc rotate

control disc andcontrol disc and

shaft with pinion shaft with pinion & lock pawl & lock pawl

Control discControl disc

It is a circular disc with It is a circular disc with notch on outer periphery notch on outer periphery

Edges of notch are vertical Edges of notch are vertical

Function of control disc areFunction of control disc are

Allow the top roller (roller Allow the top roller (roller A) to fall in side respective A) to fall in side respective notch at end friction clutch notch at end friction clutch rotationrotation

Prevent upward movement Prevent upward movement of top roller (lock the top of top roller (lock the top roller)roller)

Control disc inner view

Control disc outer view

Notch for top roller

Studs for non trail able block

Lift out discLift out disc

It is circular disc with notch It is circular disc with notch on outer periphery.on outer periphery.It has notch on inner It has notch on inner periphery also which periphery also which engages with shoe engages with shoe expansion.expansion.It has two grooves which It has two grooves which are fill with grease & fitted are fill with grease & fitted with two grease nipples.with two grease nipples.It is first disc to rotate in It is first disc to rotate in friction clutch.friction clutch.Function Function

To lift the top roller (roller To lift the top roller (roller A) to open detection A) to open detection contacts at beginning of contacts at beginning of point operation point operation

Inner view

Outer view

GreaseNipple

Notch on outer periphery

Notch on innerperiphery

Drive DiscDrive Disc

Drive disc is a Thick circular disc & has Drive disc is a Thick circular disc & has Two projections on outer and inner periphery.Two projections on outer and inner periphery.A shaft keyed in the center A shaft keyed in the center Lock pawl and pinion fixed on one end of shaftLock pawl and pinion fixed on one end of shaftLock pawl and pinion fixed at180 degree Lock pawl and pinion fixed at180 degree opposite opposite A circular offset on outer periphery on which A circular offset on outer periphery on which gear rim rests gear rim rests Two studs which engaged with non trailable Two studs which engaged with non trailable block.block.A Small window to have access to friction clutch A Small window to have access to friction clutch adjustment nut. adjustment nut.

Projections on Inner periphery

Window

Projection on outer periphery

pinion

Lock pawl

Locking faceFor throw slid

Locking faceFor lock slids

Circular groove For gear rim

Shaft

FunctionsFunctions of Drive Disc of Drive Disc

Extend movement to shaft hence rotate Extend movement to shaft hence rotate pinion and lock pawl.pinion and lock pawl.

Restrict rotary movement to 270° and Restrict rotary movement to 270° and provide subbing provide subbing

Hold gear rim on outer peripheryHold gear rim on outer peripheryConvert rotary movement in to linear Convert rotary movement in to linear

movement movement

Gear rim & spring loaded slip rimGear rim & spring loaded slip rim

It is main part of friction It is main part of friction clutch where clutch where

rotary movement of motor rotary movement of motor is extended to other parts is extended to other parts of machineof machine

Overload protection to Overload protection to motor achieved motor achieved

Snubbing is achievedSnubbing is achieved

The main parts are The main parts are

Gear rimGear rim

Slip rimSlip rim

Shoe expansion with Shoe expansion with helical spring helical spring

GEAR RIM & SPRING LOADED SLIP RIMGEAR RIM & SPRING LOADED SLIP RIM

Shoe expansion

Helical spring

gear rim

slip rim

Gear RimGear Rim

A circular gear having 92 A circular gear having 92 teeth on it’s outer teeth on it’s outer periphery periphery

It engages with pinion of It engages with pinion of the Motor the Motor

It Accommodate slip rim It Accommodate slip rim and spring loaded shoe and spring loaded shoe expansion. expansion.

When rotated by motor It When rotated by motor It transmits rotary motion to transmits rotary motion to shoe expansion through shoe expansion through slipslip rim rim

Slip rimSlip rim

It is semicircular rim with It is semicircular rim with grips on it’s outer surface.grips on it’s outer surface.It’s width is less than the It’s width is less than the width of gear rim width of gear rim Rotate freely within gear Rotate freely within gear rim when not loaded by rim when not loaded by spring.spring.When spring loaded it When spring loaded it rotate with gear rimrotate with gear rim

Shoe expansion (locking plate right & left) and helical springShoe expansion (locking plate right & left) and helical spring

Two rectangular steel Two rectangular steel strips hold by a clamp at strips hold by a clamp at one end.one end.Other end butted against Other end butted against slip rim ends.slip rim ends.Shoe expansion extends Shoe expansion extends rotary movement of gear rotary movement of gear rim to lift out & drive disc. rim to lift out & drive disc. Helical spring placed Helical spring placed between shoe expansion between shoe expansion in compressed condition.in compressed condition.Compressed spring compel Compressed spring compel gear rim and slip rim to gear rim and slip rim to act as one pieceact as one piece

Sequence of rotation of gear &discSequence of rotation of gear &discHow different gear and disc rotate in side friction How different gear and disc rotate in side friction clutch clutch

Pinion of motor rotatesPinion of motor rotates

Gear rim, then Gear rim rotates Gear rim, then Gear rim rotates

slip rim then slip rim rotates slip rim then slip rim rotates

shoe expansion, then shoe shoe expansion, then shoe rotates rotates

lift out disc and lift out disc and

drive disc, then d.disc rotatedrive disc, then d.disc rotate

control disc andcontrol disc and

shaft with pinion shaft with pinion & lock pawl & lock pawl

How friction clutch performs? How friction clutch performs?

During normal course of During normal course of operationoperation

During obstructionDuring obstruction At end of operationAt end of operation

Friction clutch during normal course of operationFriction clutch during normal course of operation

During normal course of operationDuring normal course of operationPinion operates gear rim Pinion operates gear rim slip rim & shoe expansion rotates along with gear rim as slip rim & shoe expansion rotates along with gear rim as these are spring loaded in side gear rimthese are spring loaded in side gear rimthe edge of one shoe expansion engages in the notch on the edge of one shoe expansion engages in the notch on inner periphery of lift out disc & lift out disc rotates inner periphery of lift out disc & lift out disc rotates the same edge of one shoe expansion engages with the same edge of one shoe expansion engages with projection on drive disc also & drive disc rotates projection on drive disc also & drive disc rotates shaft rotates along with drive disc & stroke of 143mm shaft rotates along with drive disc & stroke of 143mm generated generated

Friction clutch during normal course of operationFriction clutch during normal course of operation

Gear Rim

Slip Rim

Projection on Inner peripheryOf drive disk

Shoe expansion

s

s

During obstructionDuring obstruction

The drive disc cannot rotate, as throw bar/gear rack is The drive disc cannot rotate, as throw bar/gear rack is stationarystationaryHence shoe expansion engages with projection on drive Hence shoe expansion engages with projection on drive disc also cannot rotate.disc also cannot rotate.But pinion of motor forced to rotate gear rim But pinion of motor forced to rotate gear rim Hence rotary force will appear on other shoe expansionHence rotary force will appear on other shoe expansionThe helical spring get compressed & slip rim collapse to The helical spring get compressed & slip rim collapse to reduce circumference of slip rimreduce circumference of slip rimThe gear rim alone rotates with slight friction between The gear rim alone rotates with slight friction between gear rim& slip rim.gear rim& slip rim.

During obstructionDuring obstruction

Gear Rim

Slip Rim

Projection on Inner peripheryOf drive disk

Shoe expansions

Friction clutch at end of operationFriction clutch at end of operation

At end of operation projection on outer periphery buts with At end of operation projection on outer periphery buts with bottom rod bottom rod

Obstruction is generated inside the machineObstruction is generated inside the machine

Friction clutch slips & snubbing is achieved.Friction clutch slips & snubbing is achieved.

Friction clutch at end of operationFriction clutch at end of operation

Bottom bar

Drive disc

CONTACT ASSEMBLY WITH SPRING LOADED ROLLERSCONTACT ASSEMBLY WITH SPRING LOADED ROLLERS

Contact assembly Contact assembly comprises of two spring comprises of two spring loaded contact groups loaded contact groups which are fixed inside which are fixed inside the casting. the casting. Function of the contact Function of the contact assembly: - make and assembly: - make and break the sets of break the sets of contact.contact.One group Contains two One group Contains two sets of contact fixed sets of contact fixed side by sideside by sideContact controls feed Contact controls feed (Power) to motor and (Power) to motor and point indication relaypoint indication relay

CONTACT ASSEMBLY WITH SPRING LOADED ROLLERSCONTACT ASSEMBLY WITH SPRING LOADED ROLLERS

Each Contact group comprises Each Contact group comprises of of Eight terminals in two sets Eight terminals in two sets

for wires termination for wires termination terminals sets fixed terminals sets fixed

opposite to each other on opposite to each other on the casting the casting

Eight high tensile contact Eight high tensile contact (metal strips) in two sets. (metal strips) in two sets.

Two sets of contact are fixed Two sets of contact are fixed back to back on spring loaded back to back on spring loaded bracket / crank.bracket / crank.Two sets of roller are fixed on Two sets of roller are fixed on same spring loaded bracket / same spring loaded bracket / crank.crank.Bottom roller and top rollerBottom roller and top roller A transparent cover protects A transparent cover protects all sets of contact and all sets of contact and terminals terminals The transparent cover has The transparent cover has sealing arrangement alsosealing arrangement also..

Bottom rollerTop Roller

Control contacts

Control contacts

CONTACT ASSEMBLY WITH SPRING LOADED ROLLERSCONTACT ASSEMBLY WITH SPRING LOADED ROLLERS

Terminal and finger Terminal and finger contacts are insulated contacts are insulated from metal part of from metal part of point machine.point machine.Two Finger contacts Two Finger contacts are shorted at one end are shorted at one end Carbon tip is fixed on Carbon tip is fixed on other end of Finger.other end of Finger.Outer side two sets of Outer side two sets of contact are known as contact are known as Control contact and Control contact and inner side two sets of inner side two sets of contact are known as contact are known as Detection contact.Detection contact.These contacts are These contacts are self wiping, they clean self wiping, they clean themselves during the themselves during the process of making and process of making and opening.opening.

PARTS OF CONTACT ASSEMBLYPARTS OF CONTACT ASSEMBLY

Making of contactsMaking of contacts

Making of contact depend Making of contact depend upon position of top and upon position of top and bottom roller on the bottom roller on the periphery of control disc and periphery of control disc and detection slid respectively. detection slid respectively. Detection contact in one Detection contact in one group & control contact in group & control contact in other group makes whenother group makes when top roller fall in nominated top roller fall in nominated

notch on friction clutchnotch on friction clutch bottom roller fall in bottom roller fall in

nominated notch on nominated notch on periphery detection slid periphery detection slid

Falling of top roller in notch Falling of top roller in notch proves correct locking of proves correct locking of pointpointFalling of bottom roller in Falling of bottom roller in notch on proves correct notch on proves correct setting of switches / pointssetting of switches / points..

BottomRoller Insidenotch

topRoller Insidenotch

topRoller outsidenotch

Detection contactsDetection contacts

Making of Detection Making of Detection contacts proves correct contacts proves correct setting and locking of setting and locking of switches.switches.Detection contacts are Detection contacts are classified as Normal classified as Normal detection contact (ND) and detection contact (ND) and reverse detection (RD) reverse detection (RD) contact. contact. ND contact make when ND contact make when point correctly set and lock point correctly set and lock in Normal.in Normal.RD contact make when RD contact make when point correctly set and lock point correctly set and lock in Reverse.in Reverse.if point is not set correctly if point is not set correctly and/ or not correctly locked and/ or not correctly locked then both ND contact and then both ND contact and RD contact are remain in RD contact are remain in open condition.open condition.ND contact and RD contact ND contact and RD contact are used circuit of point are used circuit of point indication relay NWKR and indication relay NWKR and RWKR respectively. RWKR respectively.

Check for Correct setting and locking of pointCheck for Correct setting and locking of point

The notches on detection slides and friction The notches on detection slides and friction clutch can be make available for bottom and top clutch can be make available for bottom and top roller by moving lock slides and detection slides.roller by moving lock slides and detection slides.Dose it Mean that ND & RD contacts can make Dose it Mean that ND & RD contacts can make even though point is not lock and set?even though point is not lock and set? proving of correct setting and locking of point proving of correct setting and locking of point by ND & RD contact is subject to condition that by ND & RD contact is subject to condition that length of ground connections between point length of ground connections between point slides are accurately adjusted.slides are accurately adjusted.This is prime check to be done at site during This is prime check to be done at site during installation & Maintenance installation & Maintenance

Control contactControl contact

Feed to motor is control through these contacts Feed to motor is control through these contacts Control contact controls feed to motor in normal course of Control contact controls feed to motor in normal course of working Types of Control contacts working Types of Control contacts Normal Control contact (NC) Normal Control contact (NC) Reverse Control contact (RC).Reverse Control contact (RC).

When points set and lock in Normal then RC contact When points set and lock in Normal then RC contact makes.makes.When points set and lock in Reverse then NC contact When points set and lock in Reverse then NC contact makes.makes.When point is not correctly set and/ or not correctly locked When point is not correctly set and/ or not correctly locked position than both NC contact &RC contact are remain in position than both NC contact &RC contact are remain in make condition. make condition. NC contact controls feed for reveres to normal operation of NC contact controls feed for reveres to normal operation of pointpointRC contact controls feed for normal to reveres operation of RC contact controls feed for normal to reveres operation of point.point.NC and RC opens as soon as point correctly set and lock in NC and RC opens as soon as point correctly set and lock in required position.required position.

Detection slidesDetection slides

D Type detection slid

C Type Detection slid

Wide notchSmall notch Threaded Stud

Brass stripe

Detection slidesDetection slides

These are two rectangular strong metal strips and two These are two rectangular strong metal strips and two threaded rods are welded at one end.threaded rods are welded at one end.Each slid have a small and a wide notch on its one of Each slid have a small and a wide notch on its one of surface.surface.These slides are connected to switches of point and used to These slides are connected to switches of point and used to prove correct setting of switches.prove correct setting of switches.Bottom Rollers of switching unit are mounted on surface of Bottom Rollers of switching unit are mounted on surface of these slides. these slides. Threaded studs welded sideways to avoid interchanging Threaded studs welded sideways to avoid interchanging position of slidesposition of slidesRectangular Brass strips are riveted on inner surfaceRectangular Brass strips are riveted on inner surfaceBrass strips avoids transfer of movement to other slid which Brass strips avoids transfer of movement to other slid which is supposed to be stationary in case of rod breakage is supposed to be stationary in case of rod breakage

Lock slidesLock slides

Lock slides Lock slides

These are two rectangular strong metal strips and two These are two rectangular strong metal strips and two threaded rods are welded at on end.threaded rods are welded at on end.Each slid have a small and a wide semicircular notch ,Each slid have a small and a wide semicircular notch , These slides are connected to switches of point and used These slides are connected to switches of point and used to lock the switches.to lock the switches.Lock segment on drive disc engages in these notchesLock segment on drive disc engages in these notchesThreaded studs welded sideways to avoid interchanging Threaded studs welded sideways to avoid interchanging position of slidesposition of slidesRectangular Brass strips are riveted on inner surfaceRectangular Brass strips are riveted on inner surfaceBrass strips avoids transfer of movement to other slid Brass strips avoids transfer of movement to other slid supposed to be stationary in case of rod breakage supposed to be stationary in case of rod breakage

Position of point/ Switches

Position of Notches on Lock slid

Position of top Roller

ND For RHS mounting

RDRHS mounting

NC RHS mounting

RC RHS mounting

Control/lift out disc

Bottom roller LHS mounting LHS mounting

LHS mounting

LHS mounting

When switching unit is not fixed on machine

Make Make Open open

Make Make Open Open

Set in normal but not locked

Available On periphery of control disc & lift disc

Open Open Make1,1a5,5a

Make2,2a6,6a

Not Available Hanging on notch of detection slides

Open Open Make2,2a6,6a

Make1,1a5,5a

Set and locked in normal Available In the notch of control disc & lift disc

Make3,3a7,7a

Open Open Make2,2a6,6a

Available In the notch of detection slides

Make4 ,4a8 ,8a

Open Open Make1,1a5 ,5a

Set in reverse but not locked

Available On periphery of control disc & lift disc

Open Open Make1,1a5,5a

Make2,2a6,6a

Not Available Hanging on notch of detection slides

Open Open Make2,2a6,6a

Make1,1a5,5a

Set and locked in reverse Available In the notch of control disc & lift disc

Open Make4 ,4a8 ,8a

Make1,1a5 ,5a

Open

Available In the notch of detection slides

Open Make3,3a7,7a

Make2,2a6,6a

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