US3209708A

US3209708A - Concentric cushioned stop construction

Info

Publication number: US3209708A
Application number: US199327A
Authority: US
Inventors: John H Spence
Original assignee: Pullman Inc
Current assignee: Pullman Standard Inc; Pullman Inc
Priority date: 1962-06-01
Filing date: 1962-06-01
Publication date: 1965-10-05
Anticipated expiration: 1982-10-05
Also published as: DE1918263U

Description

Oct. 5, 1965 J. H. sPENcE CONCENTRIG CUSHIONED STOP CONSTRUCTION 3 Sheets-Shea?l 1 Filed June l, 1962 Oct. 5, 1965 J. H. SPENCE 3,209,708

CONCENTRIC CUSHIONED STOP CONSTRUCTION Filed June 1, 1962 3 Sheets-Sheet 2 N w El JNVENToR. 13 9 w JOHN H. SPENCE.

@jy/Mam Oct. 5, 1965 J. H. sPENcE 3,209,708

CONCENTRIC CUSHIONED STOP CONSTRUCTION INVENTOR.

Bgm-1N H. SPENCE @g3/IWW United States Patent O 3,209,708 CONCENTRIC CUSHIONED STOP CONSTRUCTION John H. Spence, Chicago Heights, Ill., assignor to Pullman Incorporated, Chicago, Ill., a corporation of Delaware Filed June 1, 1962, Ser. No. 199,327 4 Claims. (Cl. 10S-454) The present invention relates to railway vehicles incorporating an impact and energy-absorbing arrangement disposed between the underframe of the car and the lading-supporting body for providing lading protection, and more particularly to the cushion pocket structure for accommodating the energy-absorbing cushioning means ernployed in such :arrangements between the underframe and the lading-supporting structure.

Railway vehicles incorporating an impact and energyabsorbing arrangement encompassed by the present invention may be of the type wherein the lading-supporting structure is in the form of a rack or the like and is structurally separate from the underframe such .that upon impact to the couplers in draft or buff, the latter is relatively movable for a limited distance as determined by the cushioned travel of the cushioning means disposed between the rack structure and the underframe. Also, the invention contemplates the type o'f railway car whi-ch employs a sliding sill carrying the couplers and which is structurally separate from the car body so as to be movablerlengthwise with respect to the car a limited distance as determined by the cushion travel of the cushioning means -disposed between the latter and the sliding sill upon impact in draft or buff at the couplers.

Common to each of these cars is the energy-absorbing cushioning means which is generally disposed in a cushion pocket formed between the coupler-carrying structure and the lading-supporting structure so that upon impact the cushioning device functions during its length of travel in either direction opposing the direction of the impact force .to absorb a portion of the energy of impact whereby the energy transmitted tothe lading supported by the ladingsupporting structure is controlled to protect the car body andthe lading carried thereon from damage.

The cushion pocket structure housing the cushioning devices conventionally includes keys or stops which are xed to the coupler-carrying structure and to the structurally separate lading-supporting structure of the car. The stops are arranged with respect to the cushioning meansy such that upon impact to the coupler-carrying structure, the keys fixed thereon are operative to compress' the cushion in the direction of the force of impact 'against the keys fixed to the lading-supporting structure. In this connection, it should be mentioned that upon impact to the couplers, the inertia of the lading-supporting structure caused by the weight of the structural components and the weight of the lading thereon is initially eifective to` maintain the lading-supporting structure substantially xed during lengthwise relative movement of the coupler-carrying structure. For this reason, the lading-supporting structure may be considered to be substantially stationary and, for convenience hereinafter, the component parts of the car which do not move during at least the first phase of total cushion travel are identied as being stationary. Accordingly, the cushioning means is compressed between the keys fixed to .the movable coupler-supporting structure and the keys of t'he stationary lading-supporting car structure.

It is an object of the present invention to provide a new and novel cushion pocket structure wherein the stops are positioned and arranged so that the resultant force of the impact force applied 4at the couplers and the resisting force provided by the cushioning means is applied substantially through the longitudinal axis of the cushioning 3,209,708 Patented Oct. 5, 1965 ice means so as to preclude substantial cocking or tilting of the component parts of the latter.

It is a further object to provide a -cushion pocket structure which is of economical an-d simple construction.

It is still a further object of the invention to provide a cushion pocket structure wherein the stops engage a cushioning means in a plane including the center longitudinal -axis thereof and are supported on channel members and vare arranged so as to lie on the shear axis thereof so as to preclude torsional twisting of the channel members.

In the drawings:

FIG. l is a fragmentary side elevational view of the type of railway oar having a rack movably supported on the underfrarne and embodying the cushion pocket structure of the present invention;

FIG. 2 is a cross-sectional View taken substantially along the lines 2 2 of FIG. 1, showing the cushion pocket structure and the cushioning device disposed therein, the cushioning device being shown in phantom so as to facilitate an illustration of some of the stop construction of the present invention;

FIG. 3 is a fragmentary plan view of the cushion pocket taken substantially along the lines 3 3 of FIG. 1;

FIG. 4 is a fragmentary longitudinal section of the structure shown in FIG. 3 with the components located in a position resulting from a bulf impact applied on the left end of the car;

FIG. 5 is a fragmentary cross-sectional view of a cushion pocket embodying the principles of the present invention and shown in a type of railway car wherein a sliding sill is mounted for sliding lengthwise movement of the underframe;

FIG. 6 is a fragmentary longitudinal section of the cushion pocket illustrated in FIG. 5 taken along line 6 6 therein, and

FIG. 7 is a fragmentary plan view of a portion of the pocket as viewed along line 7 7 in FIG. 6.

Referring now to FIGS. 1-4, there is illustrated a railway car 10 of the type in which the lading-supporting structure is in the form of a rack 11. The rack 11 is structurally separate from the underfrarne 12, such that upon impact to the couplers 13 mounted on the opposite ends thereof, in buff or draft, the underframe 12 is relatively movable to the rack 11. During such impact, the rack 11 at least initially remains substantially stationary relative to the movement of the underframe 12 due to the inertia of the weight of the structural components of the rack and the lading carried thereon. Disposed between the rack 11 and the underframe 172 is a cushion pocket structure 14 in which there is disposed a cushioning means 15 for absorbing a portion of the energy of impact applied to the couplers 13.

As shown, the rack 11 comprises essentially av pair of transversely spaced I-beam 16 extending lengthwise of the car. The transverse spacing of the beams 16 is maintained by a plurality oflengthwise spaced and transversely extending channels 17.

The undcrframe 12 may be substantially skeletonal in form and includes generally a center sill 18 formed of lengthwise vertically disposed and transversely spaced plates 19. On the upper ends of the plates 19, there is fixed a top plate 21 and across the lower ends a bottom plate 22. Fastened on the top plate 21 are guiding means 23 which are arranged to cooperate with the I-beam 16 of the rack 11 so as to maintain the latter longitudinally aligned with the underframe 12. To provide free sliding movement, the guiding means 23 may include pad-like supports 23 supplying anti-friction support surfaces for the I-beams 16. The rack 11 and underframe 12 are proportioned so that the relative movement of the underframe and rack in either direction, as limited by the travel of the cushioning means 15, is confined within the ends of the center sill 18.

The cushioning device for controlling the amount of impact energy transmitted to the rack and thereby the lading supported thereon, is of the type which, upon impact in buff or draft, is lengthwise retractable in either direction from an expanded position to a fully contracted position and during this movement provides a resisting force opposing the impact force to absorb a portion of the energy of the latter. The cushioning device employed may be of the friction, -rubber or pneumatic types or a combination of such types. In the preferred form shown, there is employed a hydraulic cushioning device having substantially constant-force travel closure characteristics and a selective cushion travel between about 20 to 40 inches, preferably 30 inches in either direction.

As shown, the cushioning device includes generally a hydraulic fluid cylinder 24, a piston head 26 telescopingly reciprocable within the cylinder 24, a tubular piston rod 27 fixed at one end to the piston head 26, a flexible tubular fluid-receiving member or invaginating tube 28 connected between the tubular cylinder 24 and the tubular piston rod 27, and spring means 29 for returning the cylinder 24 and the piston head 26 to their original expanded positions after the force of impact has been dissipated. In the embodiment shown, an additional helper spring 29a is disposed in the cushion pocket 14 adjacent to the cylinder 24.

The cylinder 24 is formed from a tube 31 including a cylinder head or closure plate 32 fixed to one end thereof and a second cylinder head 33 fixed between the ends thereof and having an opening 34 formed therein to accommodate the tubular piston rod 27. The opening 34 and the exterior wall of the piston rod 27 define an annular opening 3S which provides communication with the invaginating tube 28 fixed to the cylinder head 33 and to the piston rod 27. A closure plate 36 is sealingly fixed to the free end of the piston rod 27. The piston head 26 defines a high-pressure chamber 37 on one side thereof adjacent the closure plate 32 and a low-pressure chamber 38 on the opposite side thereof. An array of ports 39 is formed in the piston rod 27 adjacent the piston head 26 to provide communication between the high-pressure and low-pressure chambers 37 and 38 via the bore 41 of the piston rod 27.

The resistance to forces of impact applied at either of the

closure plates

32 or 36 is controlled by a metering pin 42 which is fixed to the closure plate 32 and extends through an axial opening 43 formed in the piston head 26 and is constructed so as to the restrict the flow of fluid therethrough in a manner to impart substantially constant force closure travel characteristics to the cushioning device. As shown, this is accomplished by the provision of tapered flutes 44 formed in the pin 42 so that upon relative movement of the piston head 26 with respect to the metering pin 42 for each increment of travel the fluid in the high-pressure chamber 37 serves to provide a substantially constant resisting force. In this connection, it should be mentioned that the magnitude of the resisting force of the cushioning device varies with the velocity of impact.

In operation, upon the application of an impact force at either of the follower or

closure plates

32 or 36, the piston head 26 and the cylinder 24 are movable telescopingly relative to each other. During this period, the piston head 26 is operative to displace the fluid in the high-pressure chamber 37 via the metered orifice 43 and the tubular piston rod 28 and the array of ports to the low-pressure chamber 38. Liquid in the low-pressure chamber 38 flows via the annular opening 3S in the invaginating tube. During this period of contraction, the pressure offered by the fluid in the high-pressure chamber is maintained substantially constant for each increment of travel of the piston head 26 on the metering pin 42 because of the fluted arrangement formed on the latter. The flow of the fluid into the low-pressure chamber 38 creates a turbulence which is operative to dissipate some of the impact energy in the form of heat. For a more detailed description of the cushioning device structure and its operation, reference is made to copending application Serial No. 146,769, filed on October 23, 1961, assigned to the assignee of the present invention.

The cushion pocket 14 accommodating the cushioning means 1S includes stop means 46 and 47 fixed respectively to the underframe 12 and rack 11. The underframe stop means 46 includes longitudinally spaced stops 48 abutting the oppositely disposed

closure plates

32 and 36 in the expanded or neutral position thereof, and stops 49 similarly spaced and abutting against the opposite ends of the spring 29a positioned adjacent to the cushion cylinder 31. The rack stop means 47 also includes transverse pairs of lengthwise spaced

stops

51 and 52 which abut the cushioning means and the spring 29a, respectively, in the neutral positions thereof.

The underframe stops or

keys

48 and 49 at each end of the pocket may be formed from elongate bar stock of substantially rectangular section. The

keys

48 and 49 fixed to a horizontal web 50 of an inverted support channel provided at each end of the pocket are arranged so that the geometrical centers 53 and S4 of the bearing ends or

faces

56 and 57, respectively, bearing against the

closure plates

32 and 36 and the opposite ends of spring 29a lie substantially concentric with the longitudinal axes of the cushion means 15 and spring 29a. Fixed along the ends of each of the channels 55 and mounting the latter on the underframe are upright longitudinally extending plates which underlie the horizontal web 50 adjacent the ends thereof.

The rack stops or keys 51 and S2 may also each be formed from bar stock of substantially rectangular section. Conveniently, the

keys

51 and 52 are fixed to the horizontal webs 58 of the channels 17 employed to provide the transverse spacing between the rack I-beam 16. The channels 17 forming the extremities of the cushion pocket are spaced to accommodate the full or expanded length of the cushioning device 15. As shown, the channels 17 are fixed to the I-beam 16 as by welding with the horizontal webs 58 opposing and spaced from horizontal webs 50 of the underframe channels. The stops 51 and 52 are arranged in pairs and positioned longitudinally of the channels in transversely-spaced relationship on either side of the underframe stops 48 and 49 and bear against the

closure plates

32 and 36 and the ends of the spring 29a adjacent the peripheries thereof. The faces 59 bearing against the

closure plates

32 and 36 and spring 29a are shaped such that the area of each is approximately one-half the bearing area of the underframe stops and the geometrical centers 61 of the bearing faces 59 lie along the diameter of the

closure plates

32 and 36 and the spring 29a. Moreover, the geometrical centers 61 of the bearing faces 59 of each of the pairs of

keys

51 and 52 are equidistantly spaced from the respective

geometrical centers

53 and 54 of the

underframe keys

48 and 49.

As shown, the stops or

keys

48 and 49 and 51 and 52 are fixed to the underframe and rack, respectively, by way of the channel supports 17 and 55. In view of the channel supports being asymmetrical, an impact force applied directly thereto would result in torsional stresses tending to twist the channels. In accordance with the present invention, such twisting of the channels is preeluded by use of the projecting stops 48, 49, 51 and 52 and locating the longitudinal axes of the stops to pass through the respective geometrical centers on the shear axes of the channels.

Assuming that the car is stationary and that a buff impact is applied to the coupler attached to the left end of the underframe 12, the underframe 12 moves to the right under the force of the impact and the rack 11 at least initially remains substantially stationary because of the inertia due to its own weight and the weight of the lading carried thereon. Such impact force is transmitted through the left keys or stops 48 and 49 fixed to the underframe 12, to the closure plate 36 and spring 29a and through the axial centers thereof. Simultaneously the

right keys

48 and 49 also fixed to the underframe 12, move out of contact with the closure plate 32 and spring 29a, while the right Stops or

keys

51 and 52 fixed to the rack 11 remain stationary, so that the cushioning means is compressed between the

stationary keys

51 and 52 on the right and the

underframe keys

48 and 49 on the left. During this period of compression, the cushioning device is operative to provide the resisting force counteracting the impact force, thereby to absorb a po`rtion of the energy of impact. Since the rack stops 51 and 52 are constructed such that the bearing area of the faces 59 is equally distributed on either side of the underframe stops 48 and 49 and the geometrical centers 61 thereof are also in the same diametrical plane as the

geometrical centers

53 and 54 of the underframe stops 48 and 49, the resultant force of the impact force applied at the couplers and the opposing resisting force of the cushioning means lie on the longitudinal axis of the cushioning device 15. In this manner, the opposite piston ends 26 and 36 and the cylinder 24 are not subject to misaligned forces which may tend to cock these members relatively to each other. When the force of impact has been dissipated, the

springs

29 and 29a are operative to return the cushion means, the rack, and underframe to the neutral or stationary position.

In the event a draft force of impact is applied to the left end of the underframe, the right stops on the underframe are operative to compress the cushion against the left stops on the stationary rack, so that the forces imparted to the cushion by way of the impact and the resisting force are applied along the longitudinal axis thereof in the same manner as described heretofore in connection with the buff impact.

Referring now to FIGS. 5, 6 and 7, there is illustrated the principles of the present invention embodied in the type of car wherein a sliding sill 100 is detached from and separably movable length-wise of the underframe 101 and the car body fixed thereon. This type of car may comprise generally a stationary center sill 102, including a pair of transversely-spaced side channels 103, a bottom plate 104 fixed to the lower horizontal flanges of the side channels 103, and a deck or floor of a car body suitably attached to the upper flanges thereof. Disposed within the stationary center sill enclosure 106 is the sliding sill 100 including two channel members 107 held transversely spaced by suit-able bracing means (not shown). Fixed to the remote ends of the center sill are the usual couplers (not shown). Complementary wear strips 105 may be secured to the sliding sill 100 and the stationary center sill 102. In the embodiment illustrated, two such complementary pairs of wear strips 105 are shown on the upper side of the sliding sill and cooperating with two wear strips provided on the lower side of the top plate. Similar wear strips may be provided along the bottom plate of the stationary sill. The sliding still may be guided within the stationary sill by means of angles 109 suitably fixed to the top plate as shown.

The cushioning device 15 may be identical to that employed in the embodiment illustrated in FIGS. 1-4 and is disposed in a cushion pocket 111 formed intermediate the ends of the car between the sliding sill 100 and stationary sill 102 supporting the car body or lading-supporting floor. The spring 29 in the embodiment illustrated is arranged so as to encompass the cylinder 24 of the device 15 between the

closure plates

32 and 36.

The cushion pocket 111 comprises a pair of spaced stops 112 supported by a pair of longitudinally spaced upstanding plates 113 fixed to the bottom plate 104 of the stationary center sill 102 and suitably braced by cross plates 114 extending lengthwise of the car. Each stop or key 112 may be formed of bar stock of substantially rectangular section, having a bearing face 116 abutting the

respective closure plates

32 and 36 in the expanded or neutral position of the cushioning device 15 and so that the geometrical center 11,7 thereof is coincident with the longitudinal center line of the cushioning device.

Sliding sill stops or keys 11S, which also may be formed from bar stock of substantially rectangular section, are fixed to channels 119 located at either side of the pocket 111. As shown, two such stops 118 are employed, each having bearing faces 121 of substantially equal area to that of the underframe stop. The geometrical centers 122 of the bearing faces 121 abutting the

closure plates

32 and 36, respectively in the neutral position of the sliding sill are arranged so as to lie on a diameter of the cushioning device 15. In this manner7 the geometrical centers 122 of the stops 118 lie in the same plane as the geometrical centers 117 of the underframe or stationary sill stops 112. Moreover, to preclude torsional twisting of the channels 119 on which the stop 118 are fixed, as by welding, the geometrical centers 122 are located to lie on the shear center of the channel members 119. It is also to be noted that the geometrical centers 122 of the two stops 118 secured to the sliding sill 100 are equidistantly spaced from the geometrical center 117 of the underframe or stationary stop 112. In this manner, the total area of the two bearing faces 121 of the sliding sill stop lugs is equally distributed on either side of the underframe stop 112.

The operation of the structure illustrated in FIGS. 5-7 is similar to that disclosed and discussed in connection with FIGS. l-4. Upon impact to the couplers fixed to the sliding sill 100, say for example from the left as shown in FIG. 6, the stops 118 fixed to the left end of the sliding sill 100 are operative to compress or contract the cushioning device against the stationary stop 112 fixed to the stationary center sill 102 at the right end of the cushion pocket.

Similarly, should a draft force be applied to the left end, the right stops 118 fixed to the sliding sill 100 are operative to compress the cushioning device against the left stop 112 of the stationary sill 102. As described heretofore in connection with FIGS. l-4, during compression of the device the resisting force and the impact force applied by way of the

stops

112 and 118 establish -a resultant force lying on the longitudinal axis of the cushioning device so as to preclude relative cocking or tilting of the piston and cylinder.

What is claimed is:

1. In a railway car wherein the coupler carrying structure is separate and relatively movable lengthwise of the lading supporting structure thereof, and a longitudinally axially retractable energy absorbing cushioning device is interposed between said coupler carrying structure and said lading supporting structure for controlling the energy of impact transmitted to said lading supporting structure; a cushion stop arrangement for coacting with said cushioning device comprising first stop means fixed to said coupler carrying structure in spaced lengthwise relationship to engage the opposite ends lof said cushioning device in the extended position thereof, second stop means fixed to said lading supporting structure in lengthwise spaced relationship and engageable with the opposite ends of said cushion device in the extended position, said first and second stop means each having bearing faces located in spaced transverse relationship Iat each end of said cushioning device, said bearing faces of said first and second stop means having the respective geometrical centers thereof lying substantially along a common line passing through the longitudinal axis of said cushioning device, said bearing faces of said first stop means and said second stop means further having a cross section surface area and located along said common line relative to said longitudinal axis cushioning device so that the force of impact applied on said coupler carrying structure and the resisting force of the cushioning device lie substantially along a common plane which passes through the longitudinal axis of the cushioning device whereby the resultant force of impact and the resisting force lie substantially coaxial with the longitudinal axis of said cushioning device.

2. The invention as defined in claim 1 wherein at least one of said first stop means and said second stop 1() means is mounted on a horizontal web of a transversely extending channel member fixed at its ends to one of said coupler carrying structure or said lading supporting structure with which said at least one of said first and second stop means is associated, said channel member including legs depending downwardly from the transverse edges of said horizontal web and having the terminal edges thereof free yof attachment, and wherein said at least one stop means is located on said channel member so that the geometrical centers of said at least one stop means and thereby the operational forces imposed thereon pass through the shear center of said channel member.

3. The invention as defined in claim 2 wherein said coupler carrying structure comprises a sliding sill and wherein said lading supporting structure comprises a stationary sill.

4. The invention as defined in claim 2 whereinsaid coupler carrying structure comprises an underframe and wherein said lading supporting structure comprises a rack.

References Cited by the Examiner UNITED STATES PATENTS 569,094 10/96 Dunlop 10S-454 775,271 ll/O4 Graham 267-4 1,097,961 5/14 Allyn et al. 10S-361 1,434,490 11/22 Hahl et al. 213-8 2,040,486 5/36 Kellett 10S-366 2,365,842 12/44 Rosenzweig 248-20 2,652,158 .9/53 Simonson 213-8 2,752,048 6/56 Fillion 213-8 2,973,174 2/61 Stanwick et al. 248-20 3,003,436 10/61 Peterson 213-8 3,028,019 4/62 Settles et al. 213-8 3,082,708 3/63 Peterson 213-8 3,143,082 8/64 Austgen 10S-366 3,143,083 8/64 Gutridge et al. 10S-368 MILTON BUCHLER, Primary Examiner.

LEO QUACKENBUSH, Examiner.

Claims

1. IN A RAILWAY CAR WHEREIN THE COUPLER CARRYING STRUCTURE IS SEPARATE AND RELATIVELY MOVABLE LENGTHWISE OF THE LADING SUPPORTING STRUCTURE THEREOF, AND A LONGITUDINALLY AXIALLY RETRACTABLE ENERGY ABSORBING CUSHIONING DEVICE IS INTERPOSED BETWEEN SAID COUPLER CARRYING STRUCTURE AND SAID LADING SUPPORTING STRUCTURE FOR CONTROLLING THE ENERGY OF IMPACT TRANSMITTED TO SAID LADING SUPPORTING STRUCTURE; A CUSHION STOP ARRANGEMENT FOR COACTING WITH SAID CUSHIONING DEVICE COMPRISING FIRST STOP MEANS FIXED TO SAID COUPLER CARRYING STRUCTURE IN SPACED LENGTHWISE RELATIONSHIP TO ENGAGE THE OPPOSITE ENDS OF SAID CUSHIONING DEVICE IN THE EXTENDED POSITION THEREOF, SECOND STOP MEANS FIXED TO SAID LADING SUPPORTING STRUCTURE IN LENGTHWISE SPACED RELATIONSHIP AND ENGAGEABLE WITH THE OPPOSITE ENDS OF SAID CUSHION DEVICE IN THE EXTENDED POSITION, SAID FIRST AND SECOND STOP MEANS EAC H HAVING BEARING FACES LOCATED IN SPACED TRANSVERSE RELATIONSHIP AT EACH END OF SAID CUSHIONING DEVICE, SAID BEARING FACES OF SAID FIRST AND SECOND STOP MEANS HAVING THE RESPECTIVE GEOMETRICAL CENTERS THEREOF LYING SUBSTANTIALLY ALONG A COMMON LINE PASSING THROUGH THE LONGITUDINAL AXIS OF SAID CUSHIONING DEVICE, SAID BEARING FACES OF SAID FIRST STOP MEANS AND SAID SECOND STOP MEANS FURTHER HAVING A CROSS SECTION SURFACE AREA AND LOCATED ALONG SAID COMMON LINES RELATIVE TO SAID LONGITUDINAL AXIS OF THE CUSHIONING THAT THE FORCE OF IMPACT APPLIED ON SAID COUPLER CARRYING STRUCTURE AND THE RESTING FORCE OF THE CUSHIONING DEVICE LIE SUBSTANTIALLY ALONG A COMMON PLANE WHICH PASSES THROUGH THE LONGITUDINAL AXIS OF THE CUSHIONING DEVICE WHEREBY THE RESULTANT FORCE OF IMPACT AND THE RESISTING FORCE LIE SUBSTANTIALLY COAXIAL WITH THE LONGITUDINAL AXIS OF SAID CUSHIONING DEVICE.