Railway freight car draft gear assembly

Abstract

A draft gear assembly for use with railcars having coupler members is provided. The draft gear assembly has front and back ends and comprises a yoke, a coupler follower, a front resilient member, an intermediate stop member, and a back resilient member. The yoke has a back wall, a top wall extending from the back wall toward the front end of the draft gear assembly, and a bottom wall extending from the back wall toward the front end of the draft gear assembly. The coupler follower is positioned between the butt end of the coupler shank and the front end of the draft gear assembly. The front resilient member is positioned between the coupler follower and the intermediate stop member. The back resilient member is positioned between the intermediate stop member and the yoke back wall. The front and back resilient members are compressible.

Claims

1. A draft gear assembly for use with railway freight cars, the draft gear assembly having a front end and a back end and comprising: a draft sill; a yoke having a rear wall and being shiftable relative to the draft sill between a buff position, a neutral position, and a draft position, a front draft gear adjacent a butt end of a coupler shank, the front draft gear including a front follower, a back follower, and a front resilient member therebetween; a back draft gear adjacent the rear wall of the yoke, the back draft gear including a front follower, a back follower, and a back resilient member therebetween, an intermediate stop member between the front draft gear and the back draft gear, a yoke intermediate stop of the yoke between the front draft gear and the back draft gear, the yoke intermediate stop being shiftable relative to the intermediate stop member with shifting of the yoke between the buff position, neutral position, and draft position; the front resilient member and the back resilient member being compressible, the draft sill having front stops, the front draft gear including a front stop surface for contact with the draft sill front stops, the draft sill having rear stops, the back draft gear including a back stop surface for contact with the draft sill rear stops, the front draft gear including a back stop surface contacting the yoke intermediate stop with the yoke in the neutral position, and the back draft gear including a front stop surface contacting the yoke intermediate stop with the yoke in the neutral position.

2. The draft gear assembly of claim 1, wherein the front draft gear front stop surface contacting the draft sill front stops during a draft condition of the draft gear assembly, and the back draft gear back stop surface contacting the draft sill rear stops during a buff condition of the draft gear assembly.

3. The draft gear assembly of claim 1, wherein the back stop surface of the front draft gear contacting the intermediate stop member during a buff condition of the draft gear assembly, the back draft gear includes a front stop surface, and the yoke intermediate stop contacting the back draft gear front stop surface during a buff condition of the draft gear assembly.

4. The draft gear assembly of claim 3 wherein the front and back draft gears are compressed during a buff condition with a buff force being applied to the front draft gear by contact with the coupler shank, and the buff force being applied to the back draft gears by contact between the back draft gear and the yoke intermediate stop, such that the resilient members of the front and back draft gears being compressed during the buff condition such that a total compressive strength of the front resilient member and the back resilient member is the compressive strength of the front resilient member added to the compressive strength of the back resilient member.

5. The draft gear assembly of claim 1, wherein the intermediate stop member comprises an outer body structure of a generally elongated rectangular shape forming a generally rectangular opening, and an internal stop structure that extends inwardly from the outer body structure into the generally rectangular opening, the back stop surface of the front daft gear contacting the intermediate stop member internal stop structure during a buff condition of the draft gear assembly, the front stop surface of the back draft gear contacting the yoke intermediate stop during a buff condition of the draft gear assembly, and the back stop surface of the back draft gear contacting the draft sill rear stops during a buff condition of the draft gear assembly.

6. The draft gear assembly of claim 1, wherein upon a full buff force being applied to the draft gear assembly, the front resilient member and the back resilient member are compressed about 1.5 inches.

7. A draft gear assembly for use with railway freight cars, the draft gear assembly having a front end and a back end and comprising: a yoke having a rear wall and being shiftable between a buff position, a neutral position, and a draft position, a coupler having a shank with a butt end, a front draft gear positioned in operative connection with the coupler shank butt end, the front draft gear including a front resilient member, a back draft gear positioned adjacent the rear wall of the yoke, the back draft gear including a back resilient member an intermediate stop member between the front draft gear and the back draft gear, a yoke intermediate stop of the yoke between the front draft gear and the back draft gear, the yoke intermediate stop being engaged with the front draft gear and the back draft gear with the yoke in the neutral position thereof, the front resilient member and the back resilient member being compressible, such that upon a buff load being applied to the coupler, the coupler shank butt end compresses the front draft gear and the yoke intermediate stop compresses the back draft gear to share the buff load.

8. The draft gear assembly of claim 7, further comprising a draft sill having front stops, the front draft gear including a front stop surface for contact with the draft sill front stops, the draft sill having rear stops, the back draft gear including a back stop surface for contact with the draft sill rear stops, the front draft gear front stop surface contacting the draft sill front stops during a draft condition of the draft gear assembly, and the back draft gear back stop surface contacting the draft sill rear stops during a buff condition of the draft gear assembly.

9. The draft gear assembly of claim 7, wherein: the front draft gear including a back stop surface contacting the intermediate stop member during a buff condition of the draft gear assembly, the back gear includes a front stop surface, and the yoke intermediate stop contacting the back draft gear front stop surface during a buff condition of the draft gear assembly.

10. The draft gear assembly of claim 7 wherein: the front and back draft gears are compressed during a buff condition with a buff force being applied to the front draft gear by contact with the coupler butt end, and the buff force being applied to the back draft gear by contact with the yoke intermediate stop, such that the front and back resilient members being compressed during the buff condition such that a total compressive strength of the front resilient member and the back resilient member is the compressive strength of the front resilient member added to the compressive strength of the back resilient member.

11. The draft gear assembly of claim 8, wherein: the intermediate stop member comprises an outer body structure of a generally elongated rectangular shape forming a generally rectangular opening, and an internal stop structure that extends inwardly from the outer body structure into the generally rectangular opening, the front draft gear including a back stop surface contacting the intermediate stop member internal stop structure during a buff condition of the draft gear assembly, the back draft gear includes a front stop surface contacting the yoke intermediate stop during a buff condition of the draft gear assembly, and the back draft gear back stop surface contacting the draft sill rear stops during a buff condition of the draft gear assembly.

12. The draft gear assembly of claim 7, wherein upon a full buff force being applied to the draft gear assembly, the front resilient member and the back resilient member are compressed about 1.5 inches.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings,

(2) FIG. 1 is a side view of a prior art coupler and draft gear in a neutral position;

(3) FIG. 2 is a top view of a prior art coupler and draft gear in a neutral position;

(4) FIG. 3 is a top view of a prior art coupler and draft gear in a buff position;

(5) FIG. 4 is a top view of a prior art coupler and draft gear in a draft position;

(6) FIG. 5 is a side view of a coupler and draft gear in accordance with an embodiment of the present invention in a neutral position;

(7) FIG. 6 is a top view of a coupler and draft gear in accordance with an embodiment of the present invention in a neutral position;

(8) FIG. 7 is a top view of a coupler and draft gear in accordance with an embodiment of the present invention in a buff position;

(9) FIG. 8 is a top view of a coupler and draft gear in accordance with an embodiment of the present invention in a draft position.

DETAILED DESCRIPTION

(10) Referring to FIGS. 1-4,

(11) Each end of a railroad freight car utilizes a coupler 1 that allows it to be coupled to an adjacent railcar. The coupler 1 is connected to a yoke 2 by a pin 3. A known draft gear 4 is fitted inside the yoke 2. This coupler, yoke, draft gear assembly is fitted into a draft sill 5 which is part of the railcar underframeat each end of the railcar. The assembly fits between buff (push) stops 6 and draft (pull) stops 7. The draft gear acts as a shock absorber during buff (push) and draft (pull) movements of the connections between railcars. In the existing art, the draft sill and yoke are constructed to be fitted with a single draft gear.

(12) In a buff (push) movement between railcars, the coupler 1 which is constructed with an elongated pin hole so as to not load the pin 3, engages the draft gear follower 8 compressing a spring/friction elements or elastic elements 9 into the draft gear rear follower 10 and finally into the rear buff (push) stops 6 transferring the buff load into the railcar underframe structure.

(13) In a draft (pull) movement between railcars, the coupler 1 engages the pin 3 pulling the yoke until its rear portion 10 engages the rear follower of the draft gear 11 compressing springs/friction elements or elastic elements 9 into the draft gear front follower 8 engaging the draft (pull) stops 7 transferring the draft load to the railcar underframe structure.

(14) In the existing art, the load carrying capacity of the draft gear is limited by the physical dimensions (width and height) of the draft gear pocket. The fitting of additional springs in the draft gear increases draft gear strokebut not the load carrying capacity.

(15) Referring now to FIGS. 5-8, a preferred embodiment of the present invention will now be described.

(16) Each end of a railroad freight car utilizes a coupler 21 that allows it to be coupled to an adjacent railcar. The coupler 21 is connected to a tandem (two pocket) yoke 22 by a pin 23.

(17) The yoke is constructed with two (tandem) draft gear pockets separated by a yoke intermediate stop 33 and fitted with two tandem draft gears 24 and 25. The coupler, yoke and draft gears assembly is fitted into a draft sill 26 which is part of the railcar underframe structure at both ends of the railcar. The assembly fits between buff (push) stops 27 and draft (pull) stops 28. In the invention, a new pair of intermediate stops 29 are added to the pocket to form two separate draft gear pockets 30 and 31 to accommodate the tandem draft gears 24 and 25.

(18) In a buff (push) movement between railcars, the coupler 21 which is constructed with an elongated pin hole so as to not load the pin 23, engages the draft gear 24 front follower 32 driving the yoke 22 towards the rear of the draft pocket compressing draft gear 24 into the intermediate stop 29. At the same time, the intermediate stop 33 in the yoke engages the front follower 3 4 of draft gear 25 compressing it into the rear stops 27.

(19) In a draft (pull) movement between railcars, the coupler 21 engages the pin 23 pulling the yoke intermediate stop 33 into the rear follower 36 of draft gear 24 compressing the draft gear into the draft stop 28 At the same time, the rear portion of the yoke 22 engages the rear follower 37 of draft gear 25 compressing it into the intermediate stop 29.

(20) In operation, the tandem draft gears act independently effectively putting them in parallel. The independent parallel operation of the tandem draft gears effectively reduces the unit loading on the draft gears by 50% thereby increasing draft gear life and increasing load carrying capacity over a single draft gear by 100%.