US1710335A - Railway switch - Google Patents

Description

April 192.9.. 0. w. ANDERSEN RAILWAY s wncn Filed April 6. 1928 3 Sheets-Shem if i, I llrlik All in. a

I- I .1 W 4 4 Patented Apr. 23, 1929.

UNITED STATES PATENT OFFICE.

OSCAR w. ANDERSEN, F OAK PARK, ILLINOIS, ASSIGNOR TO PETTIBONE MULLIKEN COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF NEW YORK.

RAILWAY SWITCH.

Application filed April 6,

My invention relates to railway switches of the so-called spring-return type in'which the switch points set in a given position relative to the main rails of thetrack are adapted to yield laterally against the action of the spring of this character means in the passage of a train through the switch.

One phase of my spring HIGHHS emp invention relates to the yed which. as structures have hitherto been provided, present the objection of requiring the use of springs of an undesirable short length considering the extent to which the springs are distorted against their spring tension in 5 the movement of the points by the train in for functioning with passing through the switch, the springs as hitherto provided being so short, of necessity, that in the repeated distortions thereof they become permanently distorted and impa red the greatest effectiveness.

Another phase of my invention relates to the provision of means for retarding the movement of the spring-pressed switch points to the normal set position of the switch following the lateral shifting of the switch points out of such position by a trainpassing through the switch, to avoid slapping action of the point rails and undue wear of the track construction.

One of my objects is to provide a construc tion of spring-return switch whereby the extent to which the spring means thereof are distorted in the movement of the switch points against the resistance of the spring is such as to avoid production of a permanent set therein in distorted condition in the continued use of the device and to avoid such set by a simple, economical and compact construction.

Another object is to provide within the space usually available in railway tracks, the spring n'ieans of the switch, the spring of which will be sufficiently strong to return the switch points to their original set position, with the required safety margin, and at the same time avoiding such deflection of the spring as will produce a permanent set.

Another object is to provide a. novel, durable and compact construction of switch structure of the spring return type and provided with retarding means, to the end that the number of parts and connections required shall be reduced to the minimum and vide a switch structure of the X928. Serial No. 267,826.

the usual complications in connection with the assembling of the parts of the switch structure and maintenance thereof minimized.

Another object is to provide a construction of switch of the spring return, retarding, type, whereby the switch-points may be readily and quickly thrown by the operator back and forth relative to the main line rails, without resistance from the retarding means and without requiring the manipulation of any parts of the structure for rendering the retarding means inactive, thus permitting a flying switch to be made which heretofore has been impossible with switch structures of the type referred to, as hitherto constructed.

Another object of my invention is to provide a switch structure of the spring return, retarding, type which will be double acting thereby permitting the trailing of trains through the switch from the main line as Well as from the turnout and preventing the possible hazard of derailment or breakage of the several parts of the switch structure in the event that the switch throwing mechanism is not operated to move the switch-points to the proper position.

Another object of the invention is to protype referred to of such construction that instead of requiring the extra long and expensive ties which are required to be used with switch structures of this type as hitherto provided, standard switch head block ties may be used; and other objects as will be manifest from the following description.

Referring to the accompanying drawings:-

Figure 1 is a plan view of the switchequipped portion of a railway track and in which my invention is incorporated. Figure 2 is a plan view, partly sectional, of that portion of the switch structure which comprises the spring portion thereof and retarding means for the switch. Figure 3 is an enlarged view in longitudinal sectional elevation of the spring means and retarding means shown in Fig. 2, the section being taken at the line 3 on Fig. 1 and viewed in the direction of the arrow, and showing arranged for the location of the switch throwing mechanism, at the side of the main track as represented in Fig. 1.

these parts 1 cated at the side of the main track opposite .ehosen to disclose mg;

' der member that shown in Fig. 1. Figure 5 is a section taken a't the line 5 on Fig. 3 and viewed in the direction of the arrow. Fig. 6 is an enlarged section taken at the line 6 on Fig. 1 and viewed in the direction of the arrow. Figure 7 is a view like Fig. 3 of a modification of the construction therein shown; and Figure 8, a section taken at the line 8 on Fig. 7 and viewed in the direction of the arrow, with certain parts omitted.

Referring to the particular switch equipped track layout illustrated in Figs. 1, 2, 3, 5 and 6, and showin one ofthe forms in which I have invention, lfi'indicates one of the rails o e main track, the other ortion thereof comprising the rail 11 and a point rail 12 of a switch device, the'rail 11 continuing from the point rail 12 in deflected condition, as represented at 13, to form one of the rails of a switch track. 4

A point rail switch comprises the point rail 12 and the point rail 14 adjacent the main rail 10. These point rails are connected together by a tie rod 15, and also, adjacent the extremities of the points, by a spring head rod 16.

The ring rod 16 is operatively connected with switch-throwing mechanism which may be of an desirable construction, that shown being 0 the type comprising a vertically extending rock shaft 17 rovided with a crank 18 pivotally connect at 19 to one end of a link 20 pivotally connected at 21 with a reciprocable rod 22.

The spring bead rod 16 comprises a cylin- 23 in which the rod 22 slidingly extends. The spring means of this head rod and which operates, in the position'of the switch points and the location of the switchthrowing mechanism as shown in Fig. 1, to yieldingl press the point rail 12 against the side'of lie rail 13 as illustrated, comprise two coil spring sections 24 and 25 located in the cylinder 23. These-spring sections, which encircle the rod 22 are of different diameters as shown and are arranged in nested, or telesooped, sition, as represented, with a membu 26, shbwn. as in the form of a tube, interposed between the telescoped portions of these springs, the member26 being provided at one end with an outwardly extending annular flange 27 and at its opposite end with an in wardly extending annular flange 28.

The coil spring section 25 extends between theend portion 29 of the cylinder; 23 and the flange27 and the coil spring section 24 extends between the flange 28 of the member 26 and a piston 30 located in the cylinder 23 and rigidly connectedwith the reduced end of the rod 22 against movement lengthwise of the latter, as by a nut 31, between which both of the sprin between the valve and the and the piston a washer 31 is interposed.

Referring now to the functioning of the spring means, the parts above described are so positioned that when the switch-throwing mechanism is in the position shown in Fig. 1, sections 24 and 25 are slightly compresse holding the switch point 12 yieldingly against the side of the rail 13. A train passing from the switch track onto the main track and thus passing through the switch, forces the point rail 12 away from the rail 13 against the combined resistance afforded by these two spring sections, which latter serve to automatically return the switch points to the position shown in Fig. 1.

The arrangement shown also comprises means for effecting relatively slow return movement of the switch points to the set position shown in Fig. 1 to prevent, in the passin of the wheels through the switch, slapping of the point 12 against the rail 13 and minimizing wear of the switch, the particular illustrated construction of these means com rising the piston 30 which is apertured, as or example by providing a plurality of openings 32 therethrough, these openings being closed by a valve 33 shown as in the form of a disk surrounding. and slidable along, a hub portion 34 of the piston 30 and backed by a coil spring 35 confined washer 31 this valve being positioned at the side of the piston 30 o posite that at which the springs extend. he valve 33 contains a relatively small opening 33 for effecting very slow initial return movement of the switch points as hereinafter described, the ribs of the piston between said openings at the face thereof opposed by this valve being preferably recessed as represented at 33 to ensure registration of the opening 33 with the openings 32 should the valve turn on the piston.

The retarding means now being described are in the nature of a dash-pot mechanism, the cylinder 23 being preferably filled with a liquid, as for example and preferably, oil, the arrangement of the parts described being such that whereby, in the movement of the cylinder 23 against the tension of the springs, in the shifting, by a train, of the point rail 12away from the rail 13, the valve 33 opens and permits of relatively free flow of the oil through the piston thereby exerting the minimum resistance to the shifting of the switch, l]? a train, out of the set position shown in These retarding means also involve the provision of a groove 36 located in, and extending len hwise along, the inner surface of the cylin er 23 which serves as a by-pass through which the oil displaced by the action of the springs in returning the switch to the set position shown in Fi 1, flows from the valve-equipped side of the eppositesi thereof. The y-pass 36 is of piston 30 to the larger cross-sectional area than the opening 33 in the valve 33 and is of such length that in the extreme position to which the cylinder 23 is moved by a train passing through the switch the piston 30 obstructs communication between the by-pass 36 and that part of the cylinder which is between the piston and the end 29 of the cylinder. Thus the initial return movement of the switch points by the action of the spring means, is very slow due to the fact that the only opening connecting the two ends of the cylinder is the very small opening 33 in the valve 33, the movement accelerating as soon as the cylinder moves to a position in which the bypass 36 communicates with both ends of the cylinder at opposite sides of the piston 30.

By providing the retarding means of this preferred construction, the movement of the switch by the engagement therewith of the succeeding 'wheels of the train in passing throu h the switch, is very slight with the mani est advantages and when the train has cleared the switch the latter, after its delayed initial movement, moves comparatively rapidly to set position.

The mechanism described also comprises a chamber 37 in communication, at 38, with the interior of the cylinder 23 the purpose of which is to ensure the maintenance of the cylinder 23 complete] filled with oil at all times, the oil charged into the apparatus only partially filling the chamber 37 to provide a space into and out of which the oil in the operation of the mechanism may flow.

In Fig. 4 I have shown an arrangement of the arts above described, suitable where the trac conditions are such that it is desired that the switch throwing mechanism be located at the side of the main track opposite that shown in Fig. 1. In this arrangement the ends of the cylinder 23 are transposed, whereby the rod 22 enters the cylinder 23 from the end thereof opposite ,that shown in Figs. 1,2 and 3, and as in this construction the rod 22 does not pass through the sprin 24 and therebserve to prevent buckling o the spring on or pressure thereis substituted for the nut 31, the nut shown at 39 which is provided with a boss 40 extending into the ad acent/end of the szpring 24. As the only di erence in these two constructions, viz, those shown in Figs. 3 and 4,

are those above stated, it will be noted that the action of this mechanism in automatically returning the switch to set position, after di. lacement by a'train assing through it, and the retarding of sucli return movement 'is performed in'the same. manner in the construction shown in Fig. 4 as in the constructionfshown in Fig. 3.

It istoften necessary that the switch be e normal set i'tion shown is provided at its -.in one direction. The

switching a train from the main track to the switch track, this switch throwing operation and thereafter the returning of the switch to normal set position, being usually performed by one of the crew of the train to be switched, it being desirable, as will be readily manifest, that the structure be so constructed as to permit both of these operations to be performed quickly and without requiring the exertion of undue force by the operator. By providing the control meehamsm for the switch structure as above described, the operations just referred to may be performed quickly, and without requiring the application of undue force, and further without requiring any manipulation of any part by the operator to render the retarding means inactive, inasmuch as the spring mechanism and the retarding mechanism for the switch points move bodily responsive to the shifting of the latter, the switch structure, upon being returned by the operator to the set position shown in Fig. 1-

following the movement of the switch mct hanism out of the set position by the manipulation of the switch-1hrowing mechanism, and becoming conditioned for automatic return of the switch points to control of the retarding means, following shifting of the switch points by a train passin" through the switch.

iteferring now to the modified construction shown in Figs. 7 and 8, this structure constitutes an embodiment of my invention Where it is desired to apply it to a switch of the so-called double spring acting type, namely, one in which the switch points may be set by the switch-throwing mechanism in either of the two extreme positions occupied by them and the switch points be rendered automatically returnable to set position in both set positions of the switch points under the control of the switch-throw mechanism.

In this construction the rod 41 corresponds with the rod 22 of the previously described construction and extends into a cylinder 42 corresponding with the cylinder 23 which 41. The rod 41 inner end with a piston 43 held against movement in one direction by a nut 44 screwed on the endof this rod. The piston 43 contains apertures represented at 43 and closed by a disk-valve 43 like the valve 33 and containing a small opening 43.

latter is slidable on the rod This valve is backed by a spring 43 bearing against a Washer 43 screwed u on the bentportion 43, the end of the cy inder 42 ad- Jacent this piston being extended outwardly as represented at 45 to present an inwardly opening recess 46 to receive the inner end o t be red 41 in the movement of the cylinder rod 41 adjacent the opposite end of the cylinder has slidable thereon a piston 47 like the piston 43 and adapted, in oneposition of the parts, to enset position under the gage a stop-surface 41 H ton 47 being valved at 49 as piston 43.

on the rod, the pisin the caserof the This construction the outer coil being represented at 50, the inner coil at 51, and the flanged cylindrical member therebetween at 52. In this construc-v tion the end of the spring 50 opposite that which abuts the outwardly-extending flange of the member 52, abuts against the inner side of the piston 47, and thespring 51 at the opposite end of the structure engages at one end the inner side of the piston 43.

In this construction provision is alsomade for retarding the return movement of the switch under the action of the spring means when moved out of either of its two-set positions. To this end the valves 43 and 49 contain the small openingsreferred to and the cylinder 42 is provided with by- passes 53 and 54 like-the hwy-pass 36, for cooperation with the pistons 43 and 47, respectively.

The mechanism of Figs. 7 and 8 is shown in the condition assumed by it when assembled with the point rails and a switchthrowing mechanism ositioned as shown in Fig. 1. In this position the :point rail 12 is yieldingly pressed against the side of the rail 13 under the action of the spring means which abut at one end against the piston 43 I and at their other end engage the piston 47 which in turn abuts at its washer against the adjacent end of the c linder 42 and exerts force on the latter ten ing to force the point rail 12 against the rail 13.

The movement oia train from the switch track 13--14 to the main track 10-11 and thus passing through the switch, forces the cylinder 42 in a direction away from the rail 13 thus placing cylinder under still greater tension and resulting in the automatic returning of the switch to the position shown in Fig. 1. In the movement of the cylinder 42 away from the rail 13, the valve of ically opens and permits of the free flow of oil through this piston. In the return movement of the cylinder 7 piston 43 closes compelling the displacement of the oil by the movement of the cylinder, first through the opening 43 in valve 43" and then through the by-pass 53 resulting in the desired retardation of the return movement of the switch points.

Assuming that it is desired the switch be set in the position opposite that shown in Fig. 1, namely, in a position in which its point 14 is yieldingly pressed against the side of the rail. 10, and in which the movement of the switch points out of such set position is against the resistance of the spring meehanism'of the switch, the operator by actuating the switch-throwing mechanism bodily moves the switch structure, in-

- also involves s ring I means like those hereinabove .describe the spring means in this piston 43 automat- 42, the valve of the,

eluding the spring means means, to a position in which the piston 43 engages the adjacent end of the cylinder, an the piston 47 is out of engagement with the opposite end of the cylinder and abuts the shoulder 41 of rod 41. The tension of the spring means is thus in a direction yieldingly holding the point rail 14 against the rai I IO the passing of a train through the switch operates ,to place the spring means under still greater tension effecting the automatic return of the points to the set position referred to afterthe train has passed be 0nd the switch.

the movement of the point rails out of the set .osition referred to the valve .49 automatica ly opens and permits of .the relatively free fiow of the oil through the piston 47-and thus without retarding action, the return movement of the switch points to set position under the action of the spring means being retarded as the only passage through which the oil can transfer from one side of the piston to the other is first through the opening in valve 49 and then through the by-pass 54.

The walls of the cylinderends and against which the piston mechanisms 43 and 47 abut as above stated, contain a series of notches 55 and 56, respectively, for the purpose of permitting free transfer of the oil into and out of the recess 46 and the vspace between the reduced end of the rod and the opening'in .thecylinder at the opposite end thereof and in which the portion of .the rod 41 of larger diameter slides, in the relative movement of the cylinder and rod.

and retarding Thus it will be understood that the con- I struction shown in Figs. 7 and 8 presents the same advantage as does the construction of the preceding figures in that the operator may throw the switch and return it, without 'opposititn from the retarding mechanism.

The feature of providing the nested or telescoped coil springs which in efi'ect operate as a singlespring is of great advantage inasmuch as the desired relatively great spring resisted movement of the switch points may be provided for, by a comparatively compact construction, without danger of distorting the spring means to such an extent that they will become permanently distorted and the proper functioning thereof impaired. By the arrangement shown and described, the two spring sections which preferably compress an equal amount per unit of force applied thereto, are equal in effect to a single spring of much greater length than either of the sections.

While I have illustrated and described certain embodiments of my invention, I do not wish to be understood as intending to limit it thereto, as the same may be variously moditied and altered and the invention embodied in other forms of constructions, parting from the spirit of my invention, it

without debeing my intention to claim my invention as fully and completely as the prior state of the art will permit.

What I claim as new, by Letters Patent, is:

1. In a spring switch, the combination of its switch points, and spring means yieldingly resisting movement of said points comprising spiral springs nested one within the other, the outer end of one of said springs being operatively associated with said switch points, means for holding the outer end of the other of said springs relatively stationary, and a member between said springs and operatively engaging the inner ends of said springs, for the purpose set forth.

2. In a spring switch, the combination of its switch points and spring means yieldingly resisting movement of said points comprising spiral springs nested one within the other, the outer end of one of said springs being operatively associated with said I switch points, means for holding the outer end of the other of said springs relatively stationary and a member between said springs and having outwardly and inwardly extending portions adjacent its ends operatively engaging, respectively, the inner ends of said springs, for the purpose set forth.

3. In a spring switch, the combination of its switch points and spring means yieldingly resisting movement of said points comprising spiral springs nested one within the other, the outer end of one of said springs being operatively associated with said switch points through abutting parts, an abutment operatively engaged by the outer end of the other of said springs, and a member located between said springs and having portions forming abutments for the inner ends of said springs.

4. In a spring switch, the combination of its switch points and spring means yieldingly resisting movement of said points comprising spiral springs nested one within the other and deflectible to substantially the same ex tent when subjected to equal forces, the outer end of one of said springs being operatively associated with said switch points, means for holding the outer end of the other of said springs relatively stationary, and a member between said springs and operatively engaging the inner ends of said springs, for the purpose set forth.

5. In a spring switch, the combination of its switch points and spring means yieldingly resisting movement of said points comprising spiral springs nested one within the other and compressible to substantially the same degree when subjected to equal forces, the outer end of one of said springs being operatively associated with said switch points through abutting parts, an abutment operatively engaged by the outer end of the other of said springs, and a member located beand desire to secure tween said springs and having portions forming abutments for the inner ends of said sprin s.

6. n a spring switch, the combination of its switch points, and spring means yielding ly resisting movement of said points comprising spiral springs nested one within the other, the outer end of one of said springs being operatively associated with said switch points, means for holding the outer end of the other of said springs relatively stationary, and a sleeve member interposed between, and operatively engaging, the inner end portions of said springs, for the purpose set forth.

7. In a spring switch, the combination of its switch points, relatively movable members one of which is operatively connected with said switch points to move therewith, spiral springs nested one within the other, the outer end of one of said springs engaging the one of said members which is operatively connected with said switch points, and the outer end of the other of said springs engaging the other one of said members, and a member between said springs and operatively engaging the inner ends of said springs, for the purpose set forth.

8. In a spring switch, the combination of its switch points, a cylinder, a member movable in said cylinder and having an abutmentportion and operatively connected with said switch points, spiral springs nested one within the other in said cylinder, the outer end of one of said springs operatively engaging said abutment-portion and the outer end of the other of said springs engaging said cylinder, and a member between said sprin and operatively engaging the inner ends of said springs, for the purpose set forth.

9. In a spring switch, the combination of its switch points, a cylinder, a member movable in said cylinder and having an abutmentportion fixed against movement along said member, said member being operatively connected with said switch points, spiral springs nested one within the other in said cylinder, the outer end of one of said springs operatively engaging said abutment portion and the. outer end of the other of said springs engaging said cylinder, and a member between said springs and opcratively engaging the inner ends of said Springs, for the purpose set forth.

10. In a spring switch, the combination of its switch points, spring means for yielding ly resisting movement of said points in one direction, switch-throwing mechanism, and means comprising relatively movable parts operatively connected with, and movable together as a unit with, said switch-throwing mechanism for retarding the return movement of said switch points under the actionof said spring means.

11. In a spring switch, the combination of its switch points, switch-throwing mechanism, spring means for yieldingly resisting the movement of said switch points in one direction, and dash-pot mechanism operatively connected with, and the parts of which are bodily movable with, said switch-throwing mechanism for retarding the return movement of said switch points under the action of said spring means.

12. In a sprlng switch, the combination of its switch points, switch-throwing mechanism, a piston member and a cylinder member one of said members being movable with said switch points and the other operatively connected with said switch-throwing mechanism, spring means for yieldingly resisting movement of said points in one direction, and means whereby fluid in the cylinder becomes displaced relatively slowly in the relative movement of said members under the action of said spring means to retard the return movement of said points.

13. In a spring switch, the combination of its switch points, switch-throwing mechanism, a piston member and a cylinder member one of said members bein movable with said switch points and the otlier operatively connected with said switch-throwing mechanism, spring means for yieldingly resisting movement of said points in one direction. said cylinder containing a fluid, and means whereby the fluid becomes displaced relatively slowly in the return movement of said members under the action of said spring means to retard the return movement of said points.

14. In a spring switch, the combination of its switch points, spring means for yieldingly resisting movement of said points away from either of their set positions, switch-throwing mechanism, and means operatively connected with, and movable as a unit with, said switchthrowing mechanism for retarding the return movement of said switch points to either of their set positions under the action of said spring means.

15. In a spring switch, the combination of its switch points, spring means for yieldably resisting movement of said points away from either of their set positions, switch-throwing mechanism, and dash-pot means operatively connected with, and movable as a unit with, said switch-throwing mechanism for retarding the return movement of said switch points to either of their set positions under the action of said spring means.

16. In a spring switch, the combination of its switch points, switch-throwing mechanism, a cylinder member and a pistonequip ed member in said cylinder member one 0 said members being movable with said switch points and the other operatively connected with said switch-throwing mechanism, said piston-equipped member comprising a rod and pistons slidable thereon in said cylinder member, stops on said rod for engagement, respectively, by said pistons, said cylinder member having portions also forming stops for said pistons, a spring device operatively engaging at its ends with said pistons, and means whereby fluid in said cylinder member becomes displaced relatively slowly in the relative movement of said members under the action of said spring means when acting in either direction to retard the return movement of said points.

17 In a spring switch, the combination of its switch points, spring means yieldingly resisting movement of said points in one direction, and means for retarding the movement of said switch points under the action of said spring means comprising'a cylinder member and a piston-equipped member in said cylinder member, one of said members operatively engaging said switchoints and the other of said members being re atively stationary, said cylinder containing a by-pass controlled by said piston and closed thereby to flow of fluid therethrough in the initial return movement of said switch points and said piston-equipped member containing an o ening communicating with the opposite en s of said cylinder in the initial return movement of said switch points and of smaller cross-sectional area than said by-pass.

18. In a spring switch, the combination of its switch points, spring means yieldingly resisting movement of said points in one direction, and means for retarding the movement of said switch points under the action of said spring means comprising a cylinder member and a piston-equipped member in said cylinder member, one of said members operatively engaging said switch-points and the other of said members being relatively stationar said cylinder containing a by-pass control ed by said piston and closed thereby to flow of fluid therethrough in the initial return movement of said switch points and the piston of said piston-equipped member containing an opening connecting with the opposite ends of said cylinder in the initial return movement of said switch-points and of smaller cross-sectional area than said by-pass.

19. In a spring switch, the combination of its switch points, spring means yieldingly resisting movement of said points in one direction, and means for retarding the movement of said switch points under the action of said spring means comprising a cylinder member and a piston-equipped member in said cylinder member, one of said members 0 eratively engaging said switch-points an the other of said members being relatively stationary. said cylinder containing a by-pass controlled by said piston and closed thereby to flow of fluid therethrough in the initial return movement of said switch points, said piston-equipped member containing an opening therethrough and a valve for said opening operating in the movement of said switch points against the action of said spring means to permit free flow of liquid through said opening and closing in the return movement of said switch points, said valve containing an openin communicating with said opening in sai piston-equipped member and of smaller cross-sectional area than said by-pass.

20. In a spring switch, the combination of its switch points, switch-throwing mechanism, and means for yieldingly resisting movement of said points away from either of their set positions and retarding the return movement of said switch points to either of their set positions comprising a cylinder member, a rod member extending into said cylinder member, pistons on said rod member and a spring in said cylinder member cooperating with said pistons, said members being relatively movable lengthwise'and one of said members being movable with said switch points and the other thereof operatively connected with said switch-throwing mechanism.

21. In a spring switch, the combination of its switch points, means for yieldingly resisting movement of said points away from either of their set positions and retarding the return movement of said switch points to either of their set positions comprising a cylinder member, a rod member extending into said cylinder member, pistons on said rod member and a spring in said cylinder member cooperating with said pistons, said members being relatively movable lengthwise thereof and one of said members being movable with said switch points, and switch -throwing mechanism.

22. In a spring-switch, the combination of its switch points, switch-throwing mechanism having an element which is movable toward and away from the track and by which said points are moved, means yieldingly resisting movement of said points comprising a cylinder member, a second member in said cylinder member, one of said members being movable relative to the other thereof, one of said members being operatively associated with said switch points and spring means in said cylinder member coacting with the latter and with said second member, and means comprising said cylinder member and said second member for retarding the return movement of said switch points under the action of said spring means.

23. In a spring switch, the combination of its switch points, switch-throwing mechanism having an element which is movable toward and away from the track, means yieldingly resisting movement of said points comprising a cylinder member, a second member in said cylinder member, one of said members being movable relative to the other thereof, one of said members being operatively associated with said switch points and the other thereof operatively connected with said switclrthrowing mechanism and spring means in said cylinder member coacting with the latter and said cylinder member, and means comprising said cylinder member and said second member for retarding the return movement of said switch points under the action of said spring means.

24. In a spring switch, the combination of its switch points, switch-throwin g mechanism having an element which is movable toward and away from the track, dash-pot mecha nism one of the relatively movable members of which is movable with said switch points and the other of which is operatively connected with said switch-throwing mechanism, and spring-means in said dash-pot mechanism for yieldingly resisting the movement of said switch points in one direction.

25. In a spring switch, the combination of its switch points, spring means for yieldingly resisting the movement of said points in one direction, switch-throwing mechanism, and means operatively connected with said switch-throwing mechanism for retarding the return movement of said switch points under the action of said spring means and comprising relatively movable parts, said spring means and said relative] movable parts of said second-named means eing movable as a unit with said switch-throwing mechanism.

26. In a spring switch, the combination of its switch points, spring means for yieldingly resisting the movement of said points away from either of their set positions, switchthrowing mechanism and means operatively connected with said switch-throwing mechanism for retarding the return movement of said switch points to either of their set positions under the action of said spring means, said spring means and said second-named means being movable as a unit with said switch-throwing mechanism.

OSCAR W. ANDER SEN.

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