AU691594B2

AU691594B2 - Rail vehicle

Info

Publication number: AU691594B2
Application number: AU20464/95A
Authority: AU
Inventors: Lutz Schwendt
Original assignee: ABB Patent GmbH
Current assignee: Mercedes Benz Group AG
Priority date: 1994-06-14
Filing date: 1995-06-02
Publication date: 1998-05-21
Anticipated expiration: 2015-06-02
Also published as: AU2046495A; DE4420686C2; DE4420686A1

Description

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AUSTRALIA

Patents Act 1990 ABB Patent GmnbH ORIG INAL COMPLETE SPECIFICATION STANDARD PATENT 0* S 9* Invention Title: "Rail vehicle" The following statement is a full description of this invention including the best method of performing it known to us:-

DESCRIPTION

The invention relates to a rail vehicle, in particular rail traction vehicle, having a brake device, which is allocated in each case to a wheel and is formed from a 4-bar linkage frame, linked to the vehicle body and in each case laterally enclosing the allocated wheel with lateral frame supports, by lateral frame supports being coupled to one another in an articulated manner via a crosspiece and being provided with brake blocks which are pivotably fastened thereto and interact with the allocated wheel, the lateral frame supports including a first lateral frame support, and a servo-unit arranged on the first lateral frame support and intended for guiding and loading the brake blocks against the allocated wheel, Brake devices for rail vehicles are known. These brake devices are distinguished by their respective main tasks, namely as an operational brake for stopping and for reducing the travelling speed on the one hand and as a quick-acting emergency or automatic brake for stopping by the quickest method in case of emergency on the other hand. Furthermore, they are distinguished by their type of construction, that is, by their type of force action. Here, a distinction is made between rail brakes, in which frictional forces are exerted directly on the rails, for example by means of 20 electromagnet, and wheel brakes, in which frictional forces are exerted on the wheels or brake bodies. Either drum or disc brakes are used as wheel brakes, in which the braking forces act via brake grippers on special brake bodies fastened to the axles, or as block brakes in which the braking forces are exerted on the wheel tyres via brake blocks.

25 Block brakes arc provided both individually and in pairs in order to brake the respectively allocated wheel. Here, each block brake forms a unit working automatically by itself, that is, with a separate allocated servo-unit for loading the brake block, irrespective of whether the brake is a single brake or of a paired design.

A further development of the paired design of block brake provides for the lateral frame supports to which the brake blocks together with the allocated servo-unit are fastened to be connected to one another via a crosspiece. In this configuration, a hydraulically or pneumatically actuated piston/cylinder arrangement is provided as servo-unit, which piston/cylinder arrangement is arranged on a lateral frame support and loads the brake bicfk located on this frame support against the allocated wheel.

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The allocated frame support with the brake block located on it is pulled against the allocated wheel via the crosspiece so that the wheel is loaded on both sides by brake blocks.

A disadvantage in this configuration is the lack of guidance of the lateral frame supports when the servo-unit is relieved of load, which leads to the brake blocks being in contact with the wheel running tread in an uncontrolled manner and thus contributing to their premature wear.

Starting from this prior art, the object of the invention is to improve a rail vehicle of the type mentioned at the beginning, preferably having a brake device designed as a block brake, to the effect that the uncontrolled contact of the brake blocks with the allocated wheel running tread is eliminated in the simplest possible manner, The present invention is achieved according to the characterising features of patent claim 1. Accordingly, provision is made for a lateral frame 15 support to be connected in a horizont'lly movable manner to a fixed part of the vehicle body or bogie by means of a sliding guide with a sliding path and, when the thrust piston is relieved of load, for the lateral frame support, by means of a spring device arranged in the sliding path, to occupy a position in 2: which the brake blocks are lifted from the allocated wheel, In the technical 20 solution to the problem pointed out above, allowance is made for the fact that the increasing distance of the brake blocks from the braking surface on the allocated wheel inevitably results in greater regulating travel until the braking action starts, to In a preferred embodiment of the invention, the sliding guide is formed by a bar which is linked to the lateral frame support, passes through the fixed part, connected to the vehicle body, in a sliding manner, and has a stop on both sides of the fixed part. Here, a compression spring arranged on the bar side facing the frame support and interacting with the bar is provided as spring device, which is supported on the fixed part and loads the bar in the direction of the allocated wheel, In this refinement of the invention, the axial play of the bar can be set exactly, for example by means of a setting nut, so that the radial distances between the braking surfaces of the brake blocks, pivotably fastened to the lateral frame supports, on the one hand and the wheel running treads on the other hand can also be set to the optimum size.

*r of b~ In order to counteract a change in this optimum setting, which change is caused by frictional wear as a result of the braking actions, according to a further embodiment of the invention, provision is made for the device to be of automatically adjusting design.

The bar is linked to the lateral frame support by means of a screw/nut arrangement guided in an elongated hole. Here, the screw/nut arrangement has one spring-loaded thrust washer which abuts on both sides of the elongated hole under prestress against its flanks.

In a further embodiment of the invention, the bar forming the sliding guide is provided with the elongated hole which accommcdates the screw/nut arrangement, But instead, the elongated hole can also be arranged in the lateral frame support.

In a preferred embodiment of the invention, the prestress is provided in such a way that the normal force acting on both sides of the elongated hole and resulting from the prestress is large enough to prevent a change in position of the screw/nut arrangement as a result of the restoring force of the :i spring device supported on the fixed part. This means that the normal braking actions or the subsequent relief of the brake unit, during which the spring device develops its restoring force, a change in the articulation point 20 of bar and lateral frame support does not take place, since the sliding resistance, assisted by the spring-loaded thrust washer, of the screw/nut arrangement, that it, its inertia, is greater than the longitudinal force originating from the spring device.

In this preferred embodiment of the invention, it is logical that the requisite change in position of the screw/nut arrangement results solely from the regulating forc:e of the servo-unit, namely the hydraulically or pneumatically actuated thrust cylinder, loading the brake blocks.

A further preferred embodiment of the invention provides for the articulation point for the connection between the lateral frame support and the bar for forming the sliding guide to be provided in each case at a distance from the articulation points of the respectively allocated brake block on the one hand and the crosspiece on the other hand.

This and further advantageous refinements are the subject matter of the subclaims.

At I 0 s The invention, advantageous refinements and improvements as well as special advantages of the invention are to be explained and described in more detail with reference to an exemplary embodiment shown in the schematic drawing, in which: Fig. 1 shows are partial side view of a wheel brake device in schematic representations; Fig. 2 shows a longitudinal section along section line II-I in Fig, 1 in enlarged representation.

Shown in schematic representation in Fig. 1 is a vehicle 10 which is to supported on a wheel 12 by means of components (not shown in more detail). The wheel 12 is provided with a brake device 14 which acts on both sides laoL

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m 9 5 and consists of a 4-bar linkage arrangement formed from lateral supporting arms 16, 17, linked in each case to the vehicle body 10, and a crosspiece 18 connecting these two'lateral supporting arms 16, 17 to one another in an articulated manner.

Each lateral supporting arm 16, 17 is provided with a pivotably fastened brake block 20, 22, the brake block 20, which in Fig. 1 acts on the left-hand side of the wheel 12, being linked directly to the allocated lateral frame support 17, whereas the brake block 22 located on the opposite side is linked to a servo-unit 24 which is designed as a piston/cylinder arrangement and is arranged in the allocated lateral frame support 16.

According to the invention, one of the two 15 lateral frame supports 16, 17, here the lateral frame support 16 shown on the right-hand side, is connected to a fixed projection 28 of the vehicle 10 by means of a sliding guide 26.

This sliding guide 26 essentially consists of a 20 bar 30 which is connected on the one side to the lateral frame support 16 and on the other side to the fixed projection 28. Further details of the sliding guide are shown in Fig. 2.

A longitudinal section through the bar 30 includ- 25 ing the parts connected to it is reproduced in Fig. 2 in 'accordance with section line II-II in Fig. 1. According to the invention, roughly up to half the length of the the bar 30 is designed as a round bolt and the other half is designed as a flat bar. The flat end of the bar 30 is provided with an elongated hole 32 in which a screw/nut arrangement 34, 35 is guided which serves to provide a connection to the lateral frame support 16. On both sides of the bar 30, the screw/nut arrangement 34, 35 has thrust washers 36, 37 which are loaded by a compression spring 38. The compression spring 38 can be prestressed by the nut The part of the bar 30 designed as a round bolt, which bar 30 passes through the fixed projection 28 in a recess 29, has a distance sleeve 40 on the left-hand side

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6 as viewed from the fixed projection 28, in which distance sleeve 40 a spring device 42 in the compressed state finds space, and a nut 44 on its free end to the right of the -projection 28, which nut 44, just like the distance sleeve 40, serves as an axial stop for the bar 30. In Fig. 2, as well as in the underlying Fig. 1, which shows the brake device 14 in the activated state, that is, with brake blocks 20, 22 applied under pressure, a distance is shown between the nut 44 and the projection 28, which distance corresponds to the restoring travel of the sliding guide 26. The sliding guide 26 moves to the left as a result of the restoring force of the spring device 42 when the brake device 14 is relieved of load. In this way, the so-called centre position of the brake blocks is set during operation in order to prevent the brake blocks coming to bear in the released state of the brake.

Furthermore, the mode of operation of the sliding guide is as follows. When the servo-unit 24 is actuated, irrespective of whether it is a hydraulically or pneumatically actuated piston/cylinder component, a force comes into effect between the associated brake block 22 and the allocated lateral frame support 16, which force ensures that the lateral frame support 16 deflects to the 25 right, as a result of which the frame support 17 on the left-hand side of the wheel 12 is carried along due to the connection via the crosspiece 18, so that the brake block 20 pivotably fastened to the frame support 17 likewise abuts against the wheel 12.

Accompanying the pivoting of the lateral frame support 16, the sliding guide 26 formed by the bar 30 is likewise moved to the right until the distance sleeve abuts against the fixed projection 28. If only a bore adapted to the shank diameter of the screw 34 is provided in the flat part of the bar 30 instead of the elongated q- hole 32, this will possibly result in only the right-hand v brake block 22 being pressed against the wheel 12, while "r 0J1 the wheel 12, since the deflection of the lateral frame 1 te poit raeblc 0 sstl a isacefo 7 support 16 required to press the brake block 20 against the wheel 12 is not possible on account of the rigid connection between the lateral frame support 16 and the bolt 26, which is run until it stops against the projection 28.

The special advantage of the elongated-hole guide 32 comes to bear here, which elongated-hole guide 32 enables the regulating travel, for example in accordance with the utilizable lining thickness of the brake blocks 20, 22, of the lateral frame support 16 to be possible to such an extent that the brake function of the brake blocks 20, 22 is always ensured by the screw/nut arrangement 34, 35 between the lateral frame support 16 and the bar 30 being shifted as required to the right as a result of the regulating force of the servo-unit 24. The normal force produced by the compression spring 38 on the thrust washers 36, 37, that is, their contact pressure on the bolt 26, is here set in such a way that a change in position does not take place merely as a result of the 20 restoring force of the spring device 42. For this, the sliding resistance of the thrust washers 36, 37 loaded by spring force is greater than the restoring force of the spring device 42.

The shifting of the attachment point between the 25 frame body 16 and the sliding guide takes place solely as a result of the regulating force of the servo-unit 24 when the latter loads the lateral frame support 16 upon brake actuation, so that the brake block 20 on the lefthand lateral frame support 17 is pressed against the allocated wheel via the crosspiece 18. In the process, the corresponding position occurs automatically.

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Claims

1. Rail vehicle, in particular rail traction vehicle, having a brake device, which is allocated in each case to a wheel and is formed from a 4-bar linkage frame linked to the vehicle and in each case laterally enclosing the allocated wheel with lateral frame supports which are coupled to one another in an articulated manner via a crosspiece and are provided with brake blocks which are pivotably fastened thereto and interact with the allocated wheel, the lateral frame supports including a first lateral frame support, and a servo- unit arranged on the first lateral frame support and intended for guiding and loading the brake blocks against the allocated wheel, characterised in that the first lateral frame support is connected in a horizontally movable manner to a fixed projection of the vehicle by means of a sliding guide with a sliding path and, when the servo-unit is relieved of a load, the first lateral frame support occupies, by means of a spring device arranged in the sliding path, a position in which the brake blocks are lifted from the allocated wheel.

2. Rail vehicle according to claim 1, characterised in that the sliding guide is formed by a bar which is formed as a bolt at one end and is linked to the first lateral frame support at the other end, and passes through the fixed projection in a sliding manner, and has a stop on both sides of the fixed 20 projection, and in that a compression spring arranged on the side facing the first lateral frame support, and interacting with the bar is provided as the spring device, which is supported on the fixed projection and loads the bolt in the direction of the allocated wheel.

3. Rail vehicle according to claim 2, characterised in that the stops 25 provided on the bolt can be preset.

S4. Rail vehicle according to any one of the preceding claims, characterised in that the position of the first lateral frame support with respect to the sliding guide is automatically adjusted.

5. Rail vehicle according to any one of the preceding claims, characterised on that the bar is linked to the first lateral frame support by means of a screw/nut arrangement guided in an elongated hole.

6. Rail vehicle according to any one of claims 4 or 5, characterised in that the screw/nut arrangement has at least one spring-loaded thrust washer which abuts under prestress against the flanks of the elongated hole. I ~P IIII r

7. Rail vehicle according to claim 6, characterised in that the prestress is provided in such a way that the normal force acting on the flanks of the elongated hole and resulting from the prestress is selected to be so great that a change in position of the screw/nut arrangement as a result of the restoring force of the spring device supported on the fixed projection is prevented.

8. Rail vehicle according to any one of claims 4 to 7, characterised in that the change in position of the screw/nut arrangement results from the regulating force of the servo-unit loading the brake blocks.

9. Rail vehicle according to any one of the preceding claims, characterised in that the elongated hole is provided in the bar.

Rail vehicle according to any one of claims 1 to 8, characterised in that the elongated hole is provided in the first lateral frame support,

11. Rail vehicle according to any one of the preceding claims, characterised in that the articulation point for the connection between the first lateral frame support and the bar is in each case provided at a distance from the articulation points of the allocated brake block and the crosspiece.

12, Rail vehicle substantially as hereinbefore described and with reference to the accompanying drawings. 0",J Dated this Twenty-fourth day of March 1998 ABB PATENT GlBH D..a DPatent Attorneys for the Applicant: SFB RICE CO S ,V% %n^ I~#Pl/rCI~ ~L lr C~ S Abstract The invention relates to a rail vehicle, in particular a rail traction vehicle, having a brake device which is allocated in each case to a wheel (12) and is formed from a 4-bar linkage frame linked to the vehicle body (10) and in each case laterally enclosing the allocated wheel (12) with lateral frame supports (16, 17) which are coupled to one another in an articulated manner via a crosspiece (18) and are provided with brake blocks (20, 22) which are pivotably fastened thereto and interact with the allocated wheel and a servo-unit (24) arranged on the one lateral frame support (16) and intended for guiding and loading the brake blocks 22) against the allocated wheel in which arrange- ment the lateral frame support (16) is connected in a .horizontally movable manner to a fixed projection (28) of the vehicle body (10) by means of a sliding guide (26) 'and, when the servo-unit (24) is relieved of load, the frame support by means of a spring device (42) arranged in the sliding path, occupies a position in which the brake blocks (20, 22) are lifted from the allocated wheel (12). 0e Significant figure: Fig. 1 *0 L- II~ Y~ L-l I~AI~B l -TCI -rql