GB2231935A

GB2231935A - Traction and buffer device for a vehicle coupling

Info

Publication number: GB2231935A
Application number: GB9009458A
Authority: GB
Inventors: Henning Rocholl; Barun Chatterjee
Original assignee: Bergische Stahl Industrie
Current assignee: Bergische Stahl Industrie
Priority date: 1989-05-05
Filing date: 1990-04-27
Publication date: 1990-11-28
Anticipated expiration: 2010-04-27
Also published as: GB9009458D0; FR2646645A1; DE3914790A1; FR2646645B1; GB2231935B

Description

:2:':2;3 -1 9D 3 ES TRACTION AND BUFFER DEVICE FOR A VEHICLE COUPLING The

present invention relates to a traction and buffer device for a vehicle coupling, especially a central buffer coupling of a rail vehicle.

A traction and buffer device is disclosed in DE 34 16 749 A1 (BSI), in which a friction spring and an elastomer cartridge are arranged one after the other, whereby the advantages of both the friction spring and the elastomer cartridge are utilised. A dis advantage of this device, however, is that the full force of the friction spring must always be used, and, because the elastomer cartridge is very soft in the initial range, the system is unstable in this range. This instability can lead to unwanted relative movement between the individual vehicles coupled by coupling means incorporating the device.

It would thus be desirable to avoid the disadvantages of the known traction and buffer device without giving up the advantages of the cartridge.

According to the present invention there is provided a traction and buffer device for a vehicle coupling, the device comprising a housing, a sleeve displaceable in the housing, a damping cartridge firmly connected at one end thereof to the sleeve and provided with an abutment ring, a piston engaging in the cartridge and provided with an abutment plate, and two friction spring columns arranged one after the other in the housing with one of the columns acting between the abutment ring and a traction abutment of the housing and the other column acting against the abutment plate.

In a preferred embodiment the device is connected with the articulation of a central buffer coupling head and comprises a hydraulic or elastomer cartridge with entering piston and at least two friction spring columns which are arranged in a traction rod housing. The cartridge is firmly connected at one end with a sleeve, which is mounted to be displaceable in the housing and under pressure bears against a friction spring comprising two columns connected one after the other. The friction spring bears against an abutment plate firmly connected with the piston, and the front friction spring column under tension is clamped between an abutment ring firmly arranged at the cartridge and a traction abutment at the housing.

Expediently, the cartridge has an internal abutment for the piston, by which the travel of the piston under tension is limited and the bias of the rear friction spring column is maintained. The cartridge can be, for example, elastomeric or hydraulic. A device embodying the invention may have the advantage that the forces of the friction spring columns and of the cartridge add up under pressure, because the stroke of the columns is at least equal to the stroke of the cartridge and the two columns are connected in parallel with the cartridge. There may also be advantages in the quasi-static loading case. The interposed friction spring compensates for and enhances the bias of the cartridge, which is very weak in the initial range. Without this interposition, the device would be very unsteady in this range and could give rise to unwanted relative movement of individual intercoupled vehicles.

An embodiment of the present invention will now be more particular- ly described, by way of example, with reference to the accompanying drawing, the single figure of which is a partly sectional view of a traction and buffer device embodying the invention.

1 Referring now to the drawing, there is shown a traction and buffer device, which is articulated by Cardan joint means to a rail vehicle by a rear cover 11 of a traction rod housing 12. A coupling head (not illustrated) is fastened to a connecting member 13 or is mounted by a sleeve coupling at a corresponding device on another such rail vehicle, so that the device functions as part of a short coupling. The member 13 is connected with a pot-shaped sleeve 14, which is mount- ed to be displaceable in the housing 12. Fastened by a thread 15 in the interior of the sleeve 14 is an elastomer cartridge 16, into which a piston 17 can enter at the other end. The piston 17 is firm ly connected with an abutment plate 18, which in turn can bear against the cover 11 from inside. The cartridge 16 at the piston end carries an abutment ring 19, by which the abutment 20 is formed. A friction spring 21, which consists of a front friction spring column 21A and a rear friction spring column 21B, is arranged between the housing 12 and the cartridge 16. The two spring columns 21A and 21B are connected with each other by way of an intermediate ring 22, which is mounted to be displaceable relative to the housing 12 as well as relative to the cartridge 16. The rear spring column 21B bears, at its end 23, against the abutment plate 18. The front spring column 21A bears against an abutment 24 in the housing 12. Moreover, the sleeve 14 bears against the spring column 21A from the front. The spring 21 is biassed in the zero position illustrated in the drawing. In use, in the case of tension exerted on the coupling head at the connecting member 13, the abutment ring 19 at the elastomer cartridge 16 will displace the intermediate ring in the direction of tension and stress the front spring column 21A, since the column 21A bears against th.e abutment 24. The bias of the fricton spring 21 holds the abutment plate 18 against the cover 11 until the piston 17 is entrained by an inner abutment of the cartridge. The abutment plate 18 then detaches from the cover 11, while the rear spring 5 column 21B retains its coherence in consequence of its bias. The tension stroke of the abutment member 13 corresponds to the spring travel of the front spring column 21A. Normally, the spring columns 21A and 21B are identical and of equal length. When the tension force acting on the connecting member 13 ceases, 10 the stressed front spring column 21A urges, by way of the intermediate ring 22 and the abutment ring 19, the cartridge 16 and the sleeve 14 into the zero position illustrated in the drawing. When pressure is exerted on the abutment member 13, the sleeve 14 is urged against the front spring column 21A, whereby the entire 15 friction spring 21 - consisting of the columns 21A and 21B - is lifted off the abutment 24, and compresses the spring 21. Since the cartridge 16 is displaced against the piston 17, the piston enters into the cartridge 16 and damps the movement. In this range, the friction spring 21 and the cartridge 16 operate in parallel. 20 By means of different lengths of the spring columns 21A and 21B, the position of the intermediate ring 22 can be varied and the tension stroke 21A can be varied as desired. It is advantageous if the total compression stroke of the spring column 21 is equal to the total operating pressure stroke of the cartridge 16.

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Claims

1. A traction and buffer device-for a vehicle coupling, the device comprising a houing, a sleeve displaceable in the housing, a damping cartridge firmly connected at one end thereof to the sleeve and provided with an abutment ring, a piston engaging in the cartridge and provided with an abutment plate, and two friction spring columns arranged one after the other in the housing with one of the columns acting between the abutment ring and a traction abutment-of the housing and the other column acting against the abutment plate.

2. A device as claimed in claim 1, wherein the cartridge is hydraulic.

3. A device as claimed in claim 1, wherein the cartridge is elastomer i c.

4. A device as claimed in any one of the preceding claims, comprising an intermediate ring arranged between the columns.

5. A'device as claimed in any one of the preceding claims, wherein the cartridge is provided with an internal abutment co-operable with the piston to limit travel thereof under tensioning of the device and to maintain the bias of the spring columns.

6. A device as claimed in any one of the preceding claims, wherein the housing is provided with articulation means for articulated mounting on a vehicle and the sleeve is provided with a coupling head for coupling to coupling means of another vehicle.

A device as cl aimed in any one of the preceding claims, wherein the total compression stroke of the two spring columns is at least equal to the full operating pressure stroke of the cartridge.

8. A device substantially as hereinbefore described with reference to the accompanying drawing.

9. A rail vehicle provided with a central buffer coupling comprising a device as claimed in any one of the preceding claims.

11 A Pub-ished 1993 &'The Paten Of:-'cE.S-a:LeHouse-66 71 High Holborn, LondonWClR4TP- Further copies maybe obtainedfrom The Patent Office Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD. Printed by Multiplex techniques ltd, St Mary Cray, Kent, Con. 1187