AU2010226880B2

AU2010226880B2 - Coupling

Info

Publication number: AU2010226880B2
Application number: AU2010226880A
Authority: AU
Inventors: Troy Bruce Ware
Original assignee: Bradken Resources Pty Ltd
Current assignee: Bradken Resources Pty Ltd
Priority date: 2009-09-30
Filing date: 2010-09-30
Publication date: 2016-10-06
Anticipated expiration: 2030-09-30
Also published as: AU2010226880A1

Abstract

A coupling unit for a railway wagon, the coupling unit comprising: 5 a draft gear arranged to secure to the railway wagon and comprising a body having a first arcuate abutment wall; and a headstock arranged to movably couple to the draft gear and having a body with a second arcuate abutment wall 10 complementary to the first abutment wall, such that, during a compression (buff) state of the coupling unit, the first and second abutment surfaces arranaged to abut and slide over one another to facilitate lateral movement of the headstock. ------ re))

Description

COUPLING

Technical Field

The present invention relates to a coupling for railway wagons and in particular those suitably dimensioned for conveying such products as sugarcane billets from a harvest site to a mill. However, the invention is not limited to this application and couplings for analogous purposes are also within the scope of the present invention .

Background

Wagons for sugarcane are typically arranged to run on narrow gauge railway. Wagon capacities vary from 3 to 18 tonnes with physical sizes varying from 3m long x 2.4m wide x 2m high up to about 12m long x 2.4m wide x 2m high. A multiplicity of wagons are interconnected to form a train and towed to a mill where wagons are usually individually disconnected, rotated and tipped into a receiving location. A requirement, therefore, is to have couplings to inter-engage wagons which can be suitably handled when full and when empty, and can readily and safely be disconnected at a mill for unloading. The coupling must be designed to withstand the buff and draw loads placed on the connection between wagons, yet it is desirable for the coupling to be sufficiently compact not to impede on the wagons operation and capacity. Coupling and decoupling within the field and at mills is required and a robust system capable of quick and easy safe operation is required .

Summary of the Invention

In a first aspect there is provided a coupling unit for a railway wagon, the coupling unit comprising: a draft gear arranged to secure to the railway wagon and comprising a body having a first arcuate convex abutment wall; and a headstock arranged to movably couple to the draft gear and having a body with a second arcuate concave abutment wall the arrangement being such that, during a compression (buff) state of the coupling unit, the arcuate first and second abutment walls are arranged to abut and slide over one another to facilitate vertical and lateral movement of the headstock.

In accordance with a second aspect there is provided a coupling unit for a railway wagon, the coupling unit comprising : a securement member arranged to secure to the railway wagon, the securement member having a body comprising a cavity extending into an opening provided on an outer wall of the body, the outer wall adjacent the opening having an arcuate convex profile defining a first abutment surface; and a headstock comprising: a shank portion having first and second ends, the first end comprising a connecting portion which, in use, is retained by and laterally movable within the cavity and the second end comprising a shoulder portion providing a second abutment surface having an arcuate concave profile complementary to the arcuate profile of the first abutment surface, such that, during a compression state of the coupling, the first and second abutment surfaces abut and slide over one another to facilitate vertical and lateral movement of the headstock relative to the securement member; and an inter-engagement member arranged to interengage with a corresponding inter-engagement member connected to a second railway wagon, for coupling the railway wagons.

In an embodiment the first abutment surface having the arcuate convex profile with the cavity defines a cut-out portion of the profile.

In an embodiment the second abutment surface having the arcuate concave profile with the shank portion extends from a central region of the profile.

In an embodiment the securement member is in the form of a draft gear.

In an embodiment the connecting portion comprises an enlarged head.

In an embodiment, a buffer is mounted within the cavity and confronts an end face of the enlarged head.

In an embodiment the end face of the enlarged head comprises a part-spherical contact surface and the confronting buffer has a complementary part-spherical profile .

In an embodiment the coupling unit further comprises a biasing device comprising a biasing member locatable within the cavity and arranged to apply a constant biasing force to the headstock for centering the connecting portion within the cavity.

In an embodiment the biasing member comprises a pair of spring loaded projecting legs which engage respective sides of the head portion for providing the constant biasing force.

In an embodiment the projecting legs depend from either side of the confronting buffer.

In an embodiment, during a non-compression state, the first and second abutment surfaces clear one another.

In an embodiment the inter-engaging member extends away from the shank portion and comprises a claw-shaped tip adapted to inter-engage with a corresponding claw-shaped tip of the second coupling unit.

In an embodiment the headstock further comprises a locking element having a retractable lock adapted to be displaced against spring biasing to allow engagement with the second coupling unit and having an operating element operable to retract the locking element for releasing the coupling unit from the second coupling unit.

In another aspect the present invention consists in a railway coupling comprising: a coupling unit adapted to inter-engage with a corresponding coupling unit mounted to a second wagon, the coupling unit comprising a draft gear arranged to be secured to an end of a chassis of the wagon and containing a cavity; a headstock having a shank portion terminating in an enlarged head portion arranged to be inserted and retained within the cavity of the draft gear, the shank carrying a foot extending transversely of the shank and a body extending away from the foot, the body having a claw-shaped tip adapted to inter-engage with a corresponding claw-shaped tip of the second coupling unit; and a locking element having a retractable lock adapted to be displaced against spring biasing to allow engagement with the second coupling and having an operating element operable to retract the locking element for releasing the coupling unit from the second coupling unit, the coupling unit being characterised by the foot having an arcuate concave profile and the draft head having a correspondingly shaped arcuate convex profile, wherein, when the coupling is in the compressed state, the arcuate concave profile of the foot and the corresponding arcuate convex profile of the draft gear are in sliding abutment whereby, within limits, the shank can be relatively displaced in any direction relative to the draft head.

In an embodiment, a buffer is mounted within the draft gear and confronts an end face of the head.

Preferably, the end face of the head of the shank is of part-spherical concave configuration and a confronting buffer has a corresponding part-spherical convex surface.

In embodiments, the coupling unit is arranged to be released by displacement of a bell crank lever pivotally connected to a portion of the shank to provide a mechanical advantage for displacing the locking element.

The locking element is preferably in the form of a vertically extending pad partially closing an entrance into a receiving cavity on the front of the shank and the locking element is arranged to be retracted in a rectilinear manner against the biasing of a helical compression spring which extends around a mounting spigot of the lock.

In an embodiment, the release handle is adapted to be displaced through approximately 60° in a horizontal plane from a normal released position to a position in which the lock element is retracted.

In yet a further aspect there is provided a headstock for a railway coupling unit, the headstock comprising: a shank portion having first and second ends, the first end comprising an enlarged head which, in use, is retained by and vertically and laterally movable within a cavity provided in a draft gear coupled to a railway wagon, and the second end comprising a shoulder portion extending transversely of the shank and providing an abutment surface having an arcuate concave profile, such that, during a compression state, the abutment surface is arranged to slidingly abut a complementary surface having an arcuate convex profile adjacent the cavity to facilitate vertical and lateral movement of the enlarged head within the cavity; and an inter-engagement member adjacent the shoulder portion arranged to inter-engage with a corresponding inter-engagement member connected to a second railway wagon, for coupling the railway wagons.

In a still further aspect there is provided a draft gear for a railway coupling unit, the draft gear comprising: a body comprising a securement member arranged to be secured to a chassis of a wagon and a headstock receiving portion comprising a segmented cavity extending into an opening providing on an outer wall of the body and which comprises an outer segment of smaller dimension than an inner segment, in use the inner segment being arranged to receive and retain an enlarged head of a shank coupled to a headstock of the railway coupling unit, the body further comprising an arcuate convex abutment surface located on the outer wall and which at least partially surrounds the opening such that, during a compression state of the coupling unit, the arcuate convex abutment surface is arranged to abut and slide over a complementary arcuate concave abutment surface provided on the headstock to facilitate vertical and later movement of the headstock relative to the draft gear.

Detailed Description of the Drawings

For illustrative purposes, an embodiment of the invention will now be described with reference to the accompanying drawings of which:

Figure 1 is a perspective view of a coupling unit comprising first and second identical couplings mated together in a coupled mode;

Figure 2a is a plan view of the coupling of Figure 1;

Figure 2b is a side elevation of the coupling of Figure 1;

Figure 2c is a rear end view of the coupling of Figure 1;

Figure 3a is cross-sectional side elevation taken along the line of line V-V of Figure 2b and showing just one coupling;

Figure 3b is a cross-sectional view of just one coupling taking along the line of VI-VI of Figure 2c and being a sectional plan view with the handle in the normal released position;

Figure 3c corresponds with Figure 3b but showing the handle in the retracted position;

Figure 3d is cross-sectional side elevation of the draft gear of the coupling and the locking assembly;

Figure 4 is a perspective view of the draft gear of the coupling and the locking assembly prior to installation;

Figure 5a is a view of the retraction unit assembled inside the coupling head and offered-up for assembly with the draft gear;

Figure 5b is a view corresponding to Figure 5a but illustrating the handle in the retracted position to provide a clearance for assembly of the head of the shank of the coupling head into the draft gear;

Figure 5c is a view of the partially assembled components with the head partly rotated to its operating position;

Figure 5d is a view of the assembly duly completed with the handle still in the retracted position and the rear buffer pad and centering springs offered up for installation;

Figure 6 is a front perspective view of the assembled coupling;

Figure 7 is a plan view showing the handled retracted and the head displaced relative to the draft gear

Figure 8 is an isometric view of a head stock in accordance with an alternative embodiment of the present invention;

Figure 9 is an isometric view of a buffer for the alternative head stock shown in Figure 8.

Description of Preferred Embodiments

Embodiments of the present invention will hereafter be described in the context of a railway coupling 10 for sugar cane wagons. However, it will be appreciated that embodiments are equally applicable for coupling any form of railway wagon or car and should not be seen as being limited to the sugar can wagon application described herein .

In general terms, the present invention provides a coupling unit comprising a securement member in the form of a draft gear arranged to secure to a railway wagon and comprising a body having a first arcuate abutment wall. A headstock of the coupling unit movably couples to the draft gear and has a body with a second arcuate abutment wall the arrangement being such that, during a compression (buff) state of the coupling unit, the first and second abutment walls are arranged to abut and slide over one another to facilitate lateral movement of the headstock.

With reference to Figures 1 through 7 there is shown a railway coupling 10 in accordance with a first particular embodiment of the present invention. The coupling 10 comprises first and second coupling units 12 and 14 which are identical and which, in the illustrated embodiment, engage together in a claw-type arrangement. For ease of explanation, only the first coupling unit 12 will hereafter be described in detail.

The coupling unit 12 comprises a securement member in the form of a draft gear 16. A body 17 of the draft gear 16 is arranged to secure to a chassis of the railway wagon.

In the illustrated embodiment, the body 17 is adapted to be bolted onto an end chassis plate of the wagon through bolts applied through the four apertures 18. The body 17 defines an interior cavity 19. An outer wall 15 of the draft gear 16, at its rearward end, comprises an opening 21 which extends into the cavity 19. In use, the cavity 19 receives and retains a connecting portion 20 of a headstock 13. A first abutment surface 25 having an arcuate profile (referred to hereafter as a first abutment wall) is provided on the outer wall 15 adjacent the opening 21. In the illustrated embodiment, the first abutment wall 25 has a part-spherical convex profile, with the cavity 19 defining a cut-out portion of the profile (i.e. the part-spherical abutment wall being centered around and surrounding the opening 21).

In the illustrated embodiment, the cavity 19 has an outer segment 23a and an inner segment 23b. Both the outer and inner segments 23a, 23b are of enlarged dimensions in the horizontal direction as shown in Figure 3b, for reasons which will become evident in subsequent paragraphs. The cavity 19 terminates in a collar 24 within which the forward portion of a transfer plate 26 extends, the transfer plate 26 having a base flange 28 which fits behind the collar 24. The transfer plate 26 has a recess for accommodating a buffer 30 for absorbing buff impact loads. In the illustrated embodiment, the buffer 30 is formed of rubber, although it will be appreciated that any suitable resilient material may be used. The perspective view of Figure 5c best shows the profile of the leading face of the buffer 30 which is a part-spherical convex profile 31 to match a corresponding part-spherical concave profile 33 at the tip of the shank 22 as best seen in Figure 3a. An alternative buffer and shank tip configuration is shown in Figures 14 and 15.

With particular reference to Figures 3b and 4, the headstock 13 comprises a shank portion 22 having first and second ends. At a first end, the shank portion 22 comprises a coupling portion in the form of a T-shaped head 20. In use, the T-shaped head 20 is received in the inner segment 23b of the cavity 19 and is moveable therein, within limits, in a lateral direction (and to a limited extent a vertical direction). The second end of the shank portion 22 terminates in a shoulder portion on which is provided a second abutment surface 44 (hereafter "a second abutment wall") having an arcuate profile which complements the profile of the first abutment wall 25. In the illustrated embodiment, the second abutment wall has a part spherical concave profile, with the shank portion 22 extending from a central region thereof.

The headstock 13 further comprises an inter-engagement member 51 arranged to inter-engage with a corresponding inter-engagement member 53 on the other coupling unit 14. The inter-engagement members 51, 53 may take any desired or conventional form suitable for achieving sufficient coupling for the railway wagons, however in the illustrated embodiment are in the form of a claw shaped tip, which will be described in more detail in subsequent paragraphs . A biasing device 32 is provided for applying a constant biasing force for centering the shank portion 22 within the cavity 19. In the illustrated embodiment, the biasing device 32 is in the form of a torsion spring arrangement, best seen in the perspective of Figure 5b comprising a pair of forwardly projecting legs 34 connected to mounting arms 36 which link through a coil spring structures 37 to transverse arms 38. The legs are installed to engage the respective sides of the shank portion 22 as seen in Figure 3a, to form a centralising function for the head shank in terms of lateral movement as discussed in more detail below.

As best shown in Figure 7, articulation of the shank head 20 relative to the draft gear 16 can occur to either lateral side with the spring legs 34 providing a centralising function. This articulation is permitted by virtue of a segmental shaped cavity 40 of the draft head as best shown in Figure 3a so that the shank portion 22 can move laterally. In use, the first abutment wall 25 of the draft gear 16 compliments and clears the second abutment wall 44 extending from the central spine of the shank 22, unless the coupling is in the compressed (buff) state where by the first and second walls 25, 44 abut and slide over one another.

In additional to the lateral displacement shown in Figure 7, the shank portion 22 can also displace in the vertical direction to a limited extent.

As previously mentioned, the inter-engagement member 51 provided by the head stock 13 is in the form of a claw shaped tip. In more detail, and with particular reference to Figure 3a, the inter-engagement member includes lateral portions 46 and 48 leading to a jaw 50 having a first shoulder 52 behind which a cavity 54 is defined and a second shoulder 56. As shown in Figure 2a, when the coupling unit 12 of Figure 3a is engaged with another coupling unit 14, the second shoulder 56 of the second unit engages within the cavity 54, admission being permitted by retraction of a lock element 58 best shown in Figures 3a and 3b. To achieve automatic coupling, leading face 57 of the second shoulder 56 of the second coupling unit abuts the face 59 of the lock of the first coupling unit thereby causing it to retract axially and compress the helical return spring 62 mounted on a spigot 64 integrally formed with the lock element. A similar function can occur with the other coupling unit 14.

As best shown in Figure 3d, the lock element 58 mounts on a normally vertical pivot pin 66 on which a roller is mounted for engaging a rearwardly facing cam surface of the actuating arm 70 of a bell crank lever 72. The bell crank lever is arranged to pivot about its mounting bolt 74 which mounts the lever on the lateral part 46. As best shown in Figure 4, the bell crank lever has a cranked arm leading to an operating handle 76 which normally is located below the draft gear, as clearly shown in Figure 3b.

To open the coupling, the handle 76 is rotated through 60° from the axial disposition of Figure 3b to the retracted position of Figure 3c, thereby pivoting rearwardly the lever 70 to displace the locking element. This causes the previously entrapped second shoulder 56 of the other coupling to be released so it may be removed from the jaw 50 .

Assembly of the coupling unit will be described with reference to Figures 3d to 5d.

The handle/lock sub-assembly of Figure 3d is mounted on the headstock 13, which is rotated 90° from its operating position and the handle displaced to its retracted position as shown in Figure 5a. The T-shaped head 20 of the shank 22 is inserted into the cavity 19 of the draft gear 16 as shown in Figure 5b and the headstock 13 rotated through the position of Figure 5c to the position of Figure 5d. Then the buffer/torsion spring rear sub-assembly is inserted into the coupling. Figure 6 shows the handle released with the lock in its operating position .

The head unit can rotate 12.5° either side of the central position. Figure 7 shows the head unit displaced and the handled moved to retract the lock.

In an alternative embodiment to that described above, the abutment wall configurations may be reversed such that the first abutment wall has a concave profile and the second abutment wall has a convex profile. In this regard it will be understood that the profiles may not be strictly spherical but have a generally spherical profile while still achieving the three dimensional movement (i.e. lateral and vertical) as previously described. Equally, for embodiments where only lateral movement is required between the headstock and draft gear, the arcuate or bow shaped abutment walls may not wholly surround the opening/shank and instead only be required on the upper and lower edges thereof.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

Claims

CLAIMS :

1. A coupling unit for a railway wagon, the coupling unit comprising: a securement member arranged to secure to the railway wagon, the securement member having a body comprising a cavity extending into an opening provided on an outer wall of the body, the outer wall adjacent the opening having an arcuate convex profile defining a first abutment surface; and a headstock comprising: a shank portion having first and second ends, the first end comprising a connecting portion which, in use, is retained by and laterally movable within the cavity and the second end comprising a shoulder portion providing a second abutment surface having an arcuate concave profile complementary to the arcuate convex profile of the first abutment surface, such that, during a compression state of the coupling, the first and second abutment surfaces abut and slide over one another to facilitate vertical and lateral movement of the headstock relative to the securement member; and an inter-engagement member arranged to interengage with a corresponding inter-engagement member connected to a second railway wagon, for coupling the railway wagons.
2. A coupling in accordance with claim 1, wherein the first abutment surface having the arcuate convex profile with the cavity defines a cut-out portion of the profile.
3. A coupling in accordance with claim 2 or claim 3, wherein the second abutment surface has the arcuate concave profile with the shank portion extends from a central region of the profile.
4. A coupling in accordance with any one of the preceding claims, wherein the securement member is in the form of a draft gear.
5. A coupling in accordance with any one of the preceding claims, wherein the connecting portion comprises an enlarged head.
6. A coupling in accordance with claim 5, wherein a buffer is mounted within the cavity and confronts an end face of the enlarged head.
7. A coupling in accordance with claim 6, wherein the end face of the enlarged head comprises a part-spherical contact surface and the buffer has a complementary part-spherical profile.
8. A coupling in accordance with any one of the preceding claims, further comprising a biasing device comprising a biasing member locatable within the cavity and arranged to apply a constant biasing force to the headstock for centering the connecting portion within the cavity.
9. A coupling in accordance with claim 8, wherein the biasing member comprises a pair of spring loaded projecting legs which engage respective sides of the head portion for providing the constant biasing force.
10. A coupling in accordance with claim 9 when dependent on claim 6, wherein the projecting legs depend from either side of the confronting buffer.
11. A coupling in accordance with any one of the preceding claims, wherein during a non-compression state, the first and second abutment surfaces clear one another.
12. A coupling in accordance with any one of the preceding claims, wherein the inter-engaging member extends away from the shank portion and comprises a claw-shaped tip adapted to inter-engage with a corresponding claw-shaped tip of the second coupling unit.
13. A coupling in accordance with claim 12, wherein the headstock further comprises a locking element having a retractable lock adapted to be displaced against spring biasing to allow engagement with the second coupling unit and having an operating element operable to retract the locking element for releasing the coupling unit from the second coupling unit.
14. A railway wagon coupling unit adapted to inter-engage with a corresponding coupling unit mounted to a second wagon, the coupling unit comprising: a draft gear arranged to be secured to an end of a chassis of a wagon and containing a cavity; a headstock having a shank portion terminating in an enlarged head portion arranged to be inserted and retained within the cavity of the draft gear, the shank carrying a foot extending transversely of the shank and a body extending away from the foot, the body having a claw-shaped tip adapted to inter-engage with a corresponding claw-shaped tip of the second coupling unit; and a locking element having a retractable lock adapted to be displaced against spring biasing to allow engagement with the second coupling and having an operating element operable to retract the locking element for releasing the coupling unit from the second coupling unit, the coupling unit being characterised by the foot having an arcuate concave profile and the draft gear having a correspondingly shaped arcuate convex profile, wherein, when the coupling is in the compressed state, the arcuate concave profile of the foot and the corresponding arcuate convex profile of the draft gear are in sliding abutment whereby, within limits, the shank can be relatively displaced in any direction relative to the draft gear.
15. A railway coupling unit in accordance with claim 14, wherein a buffer is mounted within the draft gear and confronts an end face of the head of the shank.
16. A railway coupling unit in accordance with Claim 15, wherein the end face of the head of the shank is of part-spherical concave configuration and the buffer has a corresponding part-spherical convex surface.
17. A railway coupling unit in accordance with any one of the preceding claims, wherein the coupling unit is arranged to be released by displacement of a bell crank lever pivotally connected to a portion of the shank to provide a mechanical advantage for displacing the locking element.
18. A railway coupling unit in accordance with any one of the preceding claims, wherein the locking element is in the form of a vertically extending pad partially closing an entrance into a receiving cavity on the front of the shank and the locking element is arranged to be retracted in a rectilinear manner against the biasing of a helical compression spring which extends around a mounting spigot of the lock.
19. A headstock for a railway coupling unit, the headstock comprising: a shank portion having first and second ends, the first end comprising an enlarged head which, in use, is retained by and vertically and laterally movable within a cavity provided in a draft gear coupled to a railway wagon, and the second end comprising a shoulder portion extending transversely of the shank and providing an abutment surface having an arcuate concave profile, such that, during a compression state, the abutment surface is arranged to slidingly abut a complementary surface having an arcuate convex profile adjacent the cavity to facilitate vertical and lateral movement of the enlarged head within the cavity; and an inter-engagement member adjacent the shoulder portion arranged to inter-engage with a corresponding inter-engagement member connected to a second railway wagon, for coupling the railway wagons.
20. A draft gear for a railway coupling unit, the draft gear comprising: a body comprising a securement member arranged to be secured to a chassis of a wagon and a headstock receiving portion comprising a segmented cavity extending into an opening providing on an outer wall of the body and which comprises an outer segment of smaller dimension than an inner segment, in use the inner segment being arranged to receive and retain an enlarged head of a shank coupled to a headstock of the railway coupling unit, the body further comprising an arcuate convex abutment surface located on the outer wall and which at least partially surrounds the opening such that, during a compression state of the coupling unit, the arcuate convex abutment surface is arranged to abut and slide over a complementary arcuate concave abutment surface provided on the headstock to facilitate vertical and lateral movement of the headstock relative to the draft gear.
21. A coupling unit for a railway wagon, the coupling unit comprising: a draft gear arranged to secure to the railway wagon and comprising a body having a first arcuate convex abutment wall; and a headstock arranged to movably couple to the draft gear and having a body with a second arcuate concave abutment wall, the arrangement being such that, during a compression (buff) state of the coupling unit, the arcuate first and second abutment walls are arranged to abut and slide over one another to facilitate vertical and lateral movement of the headstock relative to the draft gear.