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US1867044A - Slow release lock for railway switches - Google Patents

Slow release lock for railway switches Download PDF

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Publication number
US1867044A
US1867044A US588925A US58892532A US1867044A US 1867044 A US1867044 A US 1867044A US 588925 A US588925 A US 588925A US 58892532 A US58892532 A US 58892532A US 1867044 A US1867044 A US 1867044A
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Prior art keywords
plunger
locking
rod
switch
lock
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US588925A
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Wyant Leroy
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Hitachi Rail STS USA Inc
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Union Switch and Signal Inc
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Priority to US588925A priority Critical patent/US1867044A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B61RAILWAYS
    • B61LGUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
    • B61L5/00Local operating mechanisms for points or track-mounted scotch-blocks; Visible or audible signals; Local operating mechanisms for visible or audible signals

Definitions

  • Fig.1 is a top plan view showinga railway switch S provided with one form of slow release lock embodying my invention.
  • Fig. 2 is an enlargedsectional view taken on the line'IIII of Fig. 1.
  • Fig. 3 is an enlargedsectional view taken on'the line IIIIII of Fig. 1.
  • Fig. 1 is a top'plan view showing another form of-slow release lock embodying my in-' The switch points 2 and 2 are connected to;
  • the switch operatingdevice 6 may be of any preferredconstruction, and as hereshown is actuated by manually operable throw lever 7.
  • the lock rod 4 extends underneath the rail 1 and cooperates atits free end with a suit able switch locking and indicating device A.
  • the device A is similar inall respects to that described and claimedin Letters Patent of the United States No. 1,450,331 granted to W.' P. Neubert on April 3, 19 23, and it is believed, therefore, that for purposes of the present disclosure, the following brief 4 description of the construction and operation ofthe device A will besufiicient.
  • the device A comprises a casing '8 having a tail like projection 9.
  • the main part of the casing. is provided with a removable cover 8, and the plunger is chamfered at 19.
  • tail like projection 9 is'provided with a cover plate 9
  • a transverse slot lO which receives the lockrod 4
  • formed inthe'cover plate'f9 V is a rectangular longitudinally extending slot 11 which receives a locking plunger 12.
  • the locking plunger 12 is movable between a locking and an unlocking position,.and when the p'lungeris moved to its locking position,
  • the reference character 14 designates a.
  • rocker arm which is "pivotally mounted intermediate its ends on pin l5 secured to the casing 8-.
  • the rocker armle carries two rollers 16 and17 journalled in'such manner as to be free to rotate with respect to the arm,
  • rocker arm 14 is' shifted aeounten' clockwise direction from the extreme positionl in which it is shown in Fig. T3-, to its opposite extreme position.
  • the rocker arm 14 isof courserestored to the posi tion shown in the drawings.
  • Pivotally attachedto the p v of the rocker 14E is a vertically extending right hand end ing plunger 12 in-such manner that the lock- 7 block 20 which is biased to an upper position,
  • the block 20' operates a circuit con troller comprising-two contact fingers 21 and22 which are mounted in a block .23 of suitable insulating material secured to the casing-8.j
  • the lower contact finger 21 is fixed and is relatively rigid, whereas the upper contact finger 22 is comparatively flexible and has its free end extending betweeninsulating blocks 24' secured toth-e upper end of the block 20.
  • the parts are so proportioned that when the locking plunger 12 is r in its projected or locking position, as shownv in Fig. .3, the block 20': is forced downward ly against the action-ofits biasto a posltion in which contact.21-22 is closed.
  • the locking plunger12 is moved to itsnhlock-i ing position, however, the. block 20 is released as soon-as the chamfered end 19 clears the roller 17, and this block then rises due to the 7 becomes opened.
  • the means for operating the plunger comprises a horizontal rod 25, mounted infixed guides 26' and 27 and having one end attached to the outer or free end of the,lock-' ing plunger. 12, and the other end operatively connected with a suitable timing deviceT which I- Will describe presently.
  • a suitable timing deviceT mounteded on the rod 25 between the guides 26 and 27 is, a fixed collar 28, a compression spring 29, asleeve 30, and afixed collar 31.
  • the sleeve 30 is adaptedto slide freely on the rod 25, and is operatively connected with a pivoted manually operable lever 32 by suitable means including a connecting link 33.
  • the parts are so proportionedthat when themanually operable lever 32 occupies the positionshown, the sleeve 30 will engage the fixed collar 31 andrwill hold the locking plunger in its locking position.
  • the lever 32 is rotated to its opposite extreme position,
  • the timing device T rnay of any, suitable type and, inthe form shown in-Fig. 2, comprises a casing 35 having a cylinder 35" extending therethrough.
  • One end of the cylin- ,der35 ' is closed by a cylinderhead 36 and screw plug 45.
  • a piston rod 39 which is fastened at its right-hand end to the free end of the rod 25, extends into the cylinder 35 through a stuff-.
  • thepassage in the cylinder head 36 comprisestwo ports ,46 and48, a regulating valve 47 being interposed between these ports,
  • the regulating valve 47 maybe of any pres, ferred construction and, in the form here shown, comprises a rotatable cylindrical valve member 4'? attached to a valve stem 47
  • the valve member 4? is provided with a-pluralityof restricted-orifices ,471, one or more of which. may bejbrought into registration withtheport 48 f by turning the valve member.
  • the reservoir 43 and cylinder 35? areboth intended to be filled withfa suitable? fluid such as oil, and in orderto permitthe in- I sertion of the fluid into the reservoir and the Ll cylindenthe reservoir wall is provided with a hole which is normally closed with a With the timing deviceiT constructed in the manner just described, it will be apparent that when rod 25 is urged toward the left.
  • piston 38. will also be moved 7 toward the left, and under, these conditions,
  • valve lfi will hold valve ell. closed, so that the fluid in cylinder 35 in the left-hand side of piston 38. willbe forced to flow through regulating valve 47. The rate at which fluid;
  • valve 4:7 is relatively slow
  • the lock rod 4 extends into a transverse slot 48 formed in the casing 49 of a locking and indicating an upstanding pin 52 which enters a longitudinally extending slot 53 inthe locking plunger 50, and is arranged to be reciprocated between two extreme positions by means of a manually operable lever 54 fixed to a shaft 55.
  • Theshaft 55 is journalled shown, the rack bar 51 is moved to its rightin suitable bearings secured to the casing 49, and has fixed thereto a pinion gear 56 which meshes with the rack .bar 51.
  • Timing device T Operatively connected with the left-hand end of the locking plunger 50 is the piston rod 39 of a timing device T
  • the timing device T is similar in all respects to the timing device T previously" described with the exception that a coil spring 57 is interposed in the cylinder between the righthand side of the piston 38 and the right hand end of the cylinder.
  • the parts are so proportioned that when the lever 54 is in the position in which it is shown in the drawings, so that the locking plunger occupies that when the lever 54 is moved to its oppocupies its locking position, but that, this site extreme position, the spring 57 will; move the locking plunger-to its unlocking position at a relatively slow rate which depends, upon the adjustment of the valve47 of thetiming device T "in
  • the locking plunger 50 is arranged to control a contact 58-, indicated diagrammaticaL ly in the drawings, in such manner that this contact will be closed whentheplunger ocamt contact will becomeopencd as soon as the plunger has moved ashortv distance from, i
  • a manually operated railway switch a lock rod connected there with a locltingplunge'r adapted to cooperate with the lock rod to lock the switch inione extreme position. and movable between .a locking and an unlocking position, resilient means for moving said locking plunger from its looking to its unlocking position, and a II.
  • a manually operated railway switch a lock rod operatively con- 20 nected with said switch, a locking plunger adapted, to cooperate with the lockrod to V lock the switch in one extreme position and movable between a locking and an unlocking position, said lock rod being provided with a 28 slot, a spring connected with said lock rod in such manner that said locking plunger is v biased to its unlocking'position, a manually operable member reciprocable between two extreme positions and provided with a pin 30 which cooperates with said locking plunger 7 at said slot in such mannerthat when said member is moved to one extreme position said 7 pin will engage one end of said slot and move said lockingplunger to its locking po- 7 e35 sition but that when said member is moved to its opposite extreme position said locking plunger will be free-to move to its unlocking position in response to the bias of said spring,

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Push-Button Switches (AREA)

Description

July 12, 1932. WYANT SLOW RELEASE LOOK FOR RAILWAY SWITCHES JJW m R m% F M N R E y 0. V 0 H mm R A -w w lllm ill N. O B N K Q3 7 wn mm Rmhm 3 y 3w .w NSQS w @n v Q g k? %w Jul 12, 1932. wY 1,867,044
SLOW RELEASE LOOK FOR RAILWAY SWITCHES Filed Jan. 26, 1932 2 Sheets-Sheet 2 I INVENTOR. I Leroy "(i am.
HIS A TT ORNE Y.
Patented July 12, 1932 UNITEDVSTATES- LEROY W YAN' I, OF CHICAGO, ILLINOIS, ASSlZGi-NOTR TO THE UNION SWITCH & SIGNAL U PATENT OFFICE I COMPANY, OF SEVISSVALE, PENNSYLVANIA, A CORPQRATIQN OF PENNSYLVANIA SLOW RELEASE LocK non RAIL-WAY SWITCHES Application-filed January 26,1932. Serial No. 588,925.
My invention relates to slow release locks for railway switches. i I will describe two forms of slow release locks embodying my invention, and willthen point out the novel features thereof in claims. In the accompanyingdrawings, Fig.1 is a top plan view showinga railway switch S provided with one form of slow release lock embodying my invention. Fig. 2 is an enlargedsectional view taken on the line'IIII of Fig. 1. Fig. 3 is an enlargedsectional view taken on'the line IIIIII of Fig. 1. Fig. 1 is a top'plan view showing another form of-slow release lock embodying my in-' The switch points 2 and 2 are connected to;
getherfor simultaneous movement by a head rod 3 and a lock rod 4, and are arranged to be moved to their normal and reverse posi tions by means of an operating rod 5 which is connected at one end to the'head rod '3, and at the other end, to a switch operating device 6. The switch operatingdevice 6 may be of any preferredconstruction, and as hereshown is actuated by manually operable throw lever 7.
The lock rod 4: extends underneath the rail 1 and cooperates atits free end with a suit able switch locking and indicating device A.
' As here shown, the device A is similar inall respects to that described and claimedin Letters Patent of the United States No. 1,450,331 granted to W.' P. Neubert on April 3, 19 23, and it is believed, therefore, that for purposes of the present disclosure, the following brief 4 description of the construction and operation ofthe device A will besufiicient.
Referring particularly to Fig. 3,.the device A comprises a casing '8 having a tail like projection 9. The main part of the casing. is provided with a removable cover 8, and the plunger is chamfered at 19.
tail like projection 9 is'provided with a cover plate 9 Formed in the tail like projection '9 is'a transverse slot lO which receives the lockrod 4, and formed inthe'cover plate'f9 V is a rectangular longitudinally extending slot 11 which receives a locking plunger 12. The locking plunger 12 is movable between a locking and an unlocking position,.and when the p'lungeris moved to its locking position,
inwhich position it is shown in the drawings,
it enters notches 13 in the lock rodt and locks thewswitch points in their normal positions. vvhern however, the locking plunger 12 is moved to its unlocking position, the plunger iswithdrawnfrom'the notches {13, and the switch 'may then be reversed at the will of the operator by means of the throwlever 7. The reference character 14 designates a.
rocker arm: which is "pivotally mounted intermediate its ends on pin l5 secured to the casing 8-. The rocker armlecarries two rollers 16 and17 journalled in'such manner as to be free to rotate with respect to the arm,
Thesero-l-lers are adapted to cooperate with the locking plunger 12, and forthispurpose, the undersurface of the plunger is provided with a recess 18 and the inner end of the When the plunger is in its projected or looking position, roller 16 enters the recess 18, and roller 19 engages an unrecessed portion 18 ofthe 7 under surface of the plunger. l lnderpthese condltions, the arm 14; 1s rocked to anextreme *position 1n, a clockwisedirection, as
viewe'd in Fig: 3. When, however, the plunger is moved frolnits locking-positiont0 its unlocking position, as soon as the plunger starts to move, the roller lZis released by the. chamfered end 19 ofthe plungenand upon slight "additional movementf of the plunger, roller 16 rideszout ofrecess 18,-so
that the rocker arm 14 is' shifted aeounten' clockwise direction from the extreme positionl in which it is shown in Fig. T3-, to its opposite extreme position. When the locking plunger 12 is restoredto its' lockingposition, the' rocker arm isof courserestored to the posi tion shown in the drawings.
Pivotally attachedto the p v of the rocker 14E is a vertically extending right hand end ing plunger 12 in-such manner that the lock- 7 block 20 which is biased to an upper position,
by suitable means not shown in 'the drawings. The block 20' operates a circuit con troller comprising-two contact fingers 21 and22 which are mounted in a block .23 of suitable insulating material secured to the casing-8.j The lower contact finger 21 is fixed and is relatively rigid, whereas the upper contact finger 22 is comparatively flexible and has its free end extending betweeninsulating blocks 24' secured toth-e upper end of the block 20. The parts are so proportioned that when the locking plunger 12 is r in its projected or locking position, as shownv in Fig. .3, the block 20': is forced downward ly against the action-ofits biasto a posltion in which contact.21-22 is closed. hen
the locking plunger12 is moved to itsnhlock-i ing position, however, the. block 20 is released as soon-as the chamfered end 19 clears the roller 17, and this block then rises due to the 7 becomes opened.
action of its bias, so that contact 21-522 In accordance with my invention means are provided for operatlng the looking plunger maybe movedfrom its unlock; ing to its lockingiposition quickly, but that-a definite time interval ofadjustable length is required to movethepllunger from its looking to its unlocking position. I As here shown, the means for operating the plunger comprises a horizontal rod 25, mounted infixed guides 26' and 27 and having one end attached to the outer or free end of the,lock-' ing plunger. 12, and the other end operatively connected with a suitable timing deviceT which I- Will describe presently. Mounted on the rod 25 between the guides 26 and 27 is, a fixed collar 28, a compression spring 29, asleeve 30, and afixed collar 31. The sleeve 30 is adaptedto slide freely on the rod 25, and is operatively connected with a pivoted manually operable lever 32 by suitable means including a connecting link 33. The parts are so proportionedthat when themanually operable lever 32 occupies the positionshown, the sleeve 30 will engage the fixed collar 31 andrwill hold the locking plunger in its locking position. When, however, the lever 32 is rotated to its opposite extreme position,
the sleeve 30is moved toward theleft-on the rod 25, thus compressingthe spring 29, and
hence causing the spring to exert'a force on I the rod which moves-the rod toward the left and the locking plunger 12toward its unlock-,
ing position, the rate of movement of the "parts under these conditions being deter- J mined by thetimingdevice T as will now be .made clear 1 The timing device T rnay of any, suitable type and, inthe form shown in-Fig. 2, comprises a casing 35 having a cylinder 35" extending therethrough. One end of the cylin- ,der35 'is closed by a cylinderhead 36 and screw plug 45.
the other end is closed bya cylinder head 37 Y .A piston rod 39, which is fastened at its right-hand end to the free end of the rod 25, extends into the cylinder 35 through a stuff-.
ing box 3'7 and through a suitable hole" 37 I in the cylinder head- 37, and is attached, at its inner end, to a reciprocable piston 38 by means of a castle nut 40. The piston 38 is provided with an annular groove 38 andwith a plurality of holes 38 which" are arranged in acircle about the'piston, and which'comto hold the valve in its proper position. Lo-
cated in the casing 35' above the cylinder 35 is areser-voir 43 which is constantly connected with the cylinder 35 on the righthand sideofpiston 38througha port 42. The reservoir 43 is also constantly connected with the cylinder 35Fon the left-hand side of piston 38 through ai port- 49 in the reservoir wall and a passage-in the cylinder head36. ;As
hereshown thepassage in the cylinder head 36 comprisestwo ports ,46 and48, a regulating valve 47 being interposed between these ports,
I to control the fiow offluidthrough the ports.
The regulating valve 47 maybe of any pres, ferred construction and, in the form here shown, comprises a rotatable cylindrical valve member 4'? attached to a valve stem 47 The valve member 4? is provided with a-pluralityof restricted-orifices ,471, one or more of which. may bejbrought into registration withtheport 48 f by turning the valve member. The reservoir 43 and cylinder 35? areboth intended to be filled withfa suitable? fluid such as oil, and in orderto permitthe in- I sertion of the fluid into the reservoir and the Ll cylindenthe reservoir wall is provided with a hole which is normally closed with a With the timing deviceiT constructed in the manner just described, it will be apparent that when rod 25 is urged toward the left.
by the'spring 29 in the manner pointed out hereinbefore, piston 38. will also be moved 7 toward the left, and under, these conditions,
spring lfi will hold valve ell. closed, so that the fluid in cylinder 35 in the left-hand side of piston 38. willbe forced to flow through regulating valve 47. The rate at which fluid;
can flow through valve 4:7 is relatively slow,
and it follows that the rod will be constrained to move at a relatively slow rate, so that a-relatively long interval of time will beirequired to unlock theswitch'. When, however, rod 25 is-moved toward the right, the pressure of the flu d 1n cylinder35 on the right-hand side of piston 38 will open valve 41 and permit fluid to flow freely through the holes 38? in piston 38 into cylinder 35 on the'left-hand side of the piston. The pressure exerted on valve 41 by spring 44 is comparatively small, so that very little pressure is required to open valve 41. It will be apparent, therefore, that very little force is required to movevalve 41 toward the left, and that the resistance offered by the timing device to the movement of the rod toward the right is therefore very slight.
Referring now to the modification illustrated in Fig. 4, as here shown, the lock rod 4 extends into a transverse slot 48 formed in the casing 49 of a locking and indicating an upstanding pin 52 which enters a longitudinally extending slot 53 inthe locking plunger 50, and is arranged to be reciprocated between two extreme positions by means of a manually operable lever 54 fixed to a shaft 55. Theshaft 55 is journalled shown, the rack bar 51 is moved to its rightin suitable bearings secured to the casing 49, and has fixed thereto a pinion gear 56 which meshes with the rack .bar 51. When the lever 54 occupies the extreme position hand extreme position, and under these conditions, the pin 52 engages the right-hand end of the slot 53 and holds the locking plunger 51 in its locking position, in which position it engages the lock rod 4 at the notches 13. When, however, the lever 54 is rotated through an angle of approximately 180 from the position shown to its opposite extreme position, the rack bar 51 is then moved to its left-hand extreme position, thus moving the pin 52 to such position that the locking plunger 50 is free to be moved to its unlocking position in which it is out of engagement with the notches 13 in the lock rod 4.
Operatively connected with the left-hand end of the locking plunger 50 is the piston rod 39 of a timing device T The timing device T is similar in all respects to the timing device T previously" described with the exception that a coil spring 57 is interposed in the cylinder between the righthand side of the piston 38 and the right hand end of the cylinder. The parts are so proportioned that when the lever 54 is in the position in which it is shown in the drawings, so that the locking plunger occupies that when the lever 54 is moved to its oppocupies its locking position, but that, this site extreme position, the spring 57 will; move the locking plunger-to its unlocking position at a relatively slow rate which depends, upon the adjustment of the valve47 of thetiming device T "in The locking plunger 50 is arranged to control a contact 58-, indicated diagrammaticaL ly in the drawings, in such manner that this contact will be closed whentheplunger ocamt contact will becomeopencd as soon as the plunger has moved ashortv distance from, i
its i liing position' toward its. unlocking position.
21 22 shown iniFig. 3 or the contact 58 shown in Fig. 4 will usually bee'mployed-to control a signal for governing traffic over the associated switch, and the parts will nor mallybe so proportioned that, ifthe opera- "3! tor attempts to unlock theswitch in orderto reverse it after a train which is approaching the switch has passed thesignal, a suificient time intervalwillfelapse before the switch actually becomes uniocked to permit,the train to pass the switch, thus insuring that the switch cannot be throwniin-a mannerlto cause a dangerous conditionv 1 'Although I havehereinsho-wn and described only two forms. of slow release locks {91$ embodying my invention, it is understood that various changes'and modificationsmay be made therein within thescopeofthe appended claims witliout departinglfrom the spirit and scope ofjmy invention.
Having thus described my. invention, what Iclaimis: p
1. In combination, a manually operated railway switch, a lock rod connected there with a locltingplunge'r adapted to cooperate with the lock rod to lock the switch inione extreme position. and movable between .a locking and an unlocking position, resilient means for moving said locking plunger from its looking to its unlocking position, and a II.
its locking to its unlocking position, and means for controlling the speed of movement .125
of said, plunger. 7
3. In combination, a manually operated railway switch, a'lock rod operatively connected with said switch, a locking plunger adaptedto cooperate with said lock rod to 1 50 7 In utilizing my invention, the contact F80] 4- p 7 Q I 1,867,044
lock the switch in one extreme position and movable between a locking'and an unlocking position, means for biasing said locking plunger to its unlocking position, a manually C'ii operable member reciprocable between two extreme positions, a pin and slot connection between said member and said locking plunger so arranged that when said member occupies one extreme position said lock-i Em 'ing plunger will be moved to its locking position but that when said member ismoved to itsother extreme position said locking plunger will be free to move to its unlocking- -position under the action of said biasing (15: means, and'means for controlling the rate 1 of movement of said locking plunger in response to its bias. 7 4. In combination, a manually operated railway switch, a lock rod operatively con- 20 nected with said switch, a locking plunger adapted, to cooperate with the lockrod to V lock the switch in one extreme position and movable between a locking and an unlocking position, said lock rod being provided with a 28 slot, a spring connected with said lock rod in such manner that said locking plunger is v biased to its unlocking'position, a manually operable member reciprocable between two extreme positions and provided with a pin 30 which cooperates with said locking plunger 7 at said slot in such mannerthat when said member is moved to one extreme position said 7 pin will engage one end of said slot and move said lockingplunger to its locking po- 7 e35 sition but that when said member is moved to its opposite extreme position said locking plunger will be free-to move to its unlocking position in response to the bias of said spring,
and means for controlling the rate of move- 514,0 ment of said locking plunger in response to thebias of said spring.
In testimony whereof I aflix my signature.
LEROY lVYANT.
US588925A 1932-01-26 1932-01-26 Slow release lock for railway switches Expired - Lifetime US1867044A (en)

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