HK1115570B - Lift facility with a braking device and method for braking a lift facility - Google Patents

Description

The invention relates to an elevator system with a lifting cab and a method for braking a lifting cab as defined in the independent claims.

The lift system is installed in a shaft. The shaft is usually made of solid construction materials, but it can also be, at least partially, open. The lift system consists essentially of a cabin, for transporting people and/or goods. The cabin is connected to a counterweight by means of load-bearing equipment. By means of a drive that acts on the load-bearing equipment, directly on the cabin or the counterweight, the cabin is driven along a mainly vertical cabin track and the cabin is held in a stop or from a driving position to a stop position by means of a brake.

The operating condition usually includes normal operating procedures such as waiting on a floor or at a stop, picking up or unloading loads, moving the cab to another floor, stopping the cab or activities to perform service work on the elevator system. The emergency includes, for example, malfunctioning during operation such as overloading the cab, failure of bearings, such as cracks in a load carrier or defects in control or mechanics. More recent solutions for stopping and braking use a braking system, often located in the cabin, which, if necessary, acts to detect both operating and emergency conditions.

The brake system is known from EP0648703. A brake system mounted on the cabin is controlled as required and can meet requirements arising from the operating condition and emergency. This brake system has the property that when a brake plate is worn, an air gap changes. This causes the time to bring the brake system to braking to change, usually being increased, because a larger supply has to be removed or wear-resistant brake plates have to be broken.Other The brake system described in patent application US2006/180406 is capable of compensating for wear of brake plates. The wear compensation shown therein can compensate for a total sum of air gaps or a braking force independent of the wear of brake plates. This brake system also requires that the total sum of air gaps is selected in such a way that the wear of individual brake plates is not adversely affected. This also increases the time required to bring the brake system to brake accordingly or requires the use of wear-resistant brake plates accordingly. EP-A-1671912, which was not published at the time of the priority application, discloses a lifting system as defined in claim 1 and a procedure as defined in claim 16.Other The present invention consists in providing a lifting system with a lifting cab and a method for braking and holding a lifting cab which allows operation over a long period of time. It should be tolerant of inaccuracies in the cab's road surface and should be able to respond quickly if necessary. Furthermore, the braking system should nevertheless be able to be operated at a low cost, i.e. inter alia with low cost, wear-resistant brake plates.

The invention defined in the independent claims solves at least one of these problems. The lift system consists of a lift cabin moving vertically along guide tracks. If necessary, the lift cabin is brake or held in place by a brake device. The brake system consists of at least two brake units. Each brake unit has at least one brake liner which, if necessary, interacts with a brake track, According to the invention, at least one of the brake units, but preferably each of the brake units, shall be equipped with a wear compensation device which, when the brake unit is unloaded, adjusts the air gap between the brake lining and the brake line to an essentially constant value.

This allows the use of common and thus inexpensive brake materials which wear out during use. A worn brake material would inevitably lead to a larger air gap. A larger air gap would require a longer time to bring the brake unit into braking position. The compensation rail system of the invention now has the advantage that operation of the brake system is possible over a long period of time - as a brake compensation system compensates for any railway slip - that the brake system is tolerant of railway slip - that an air gap can be set to the expected precision and that the brake system can be set to the expected precision - that it can be used for a single railway bridge, or that it can be used for a single railway bridge, as well as for the purpose of a single railway bridge - that it cannot be used for a single railway bridge, or that it can be used for the purpose of a single railway bridge, as a result of a large number of railway slip, etc.

In an advantageous design, the brake unit comprises a brake casing, a movable brake plate relative to the brake casing and a fixed brake plate relative to the brake casing, whereby the brake plates are brought into contact with a brake line if necessary by means of a delivery device. The delivery device includes a delivery control which detects and controls an entire delivery route. The wear compensation device keeps an air gap on the side of the fixed brake plate essentially constant and the delivery device keeps an entire air gap constant. In the case of operation of the brake unit, the delivery of the movable brake plate is thus carried out in a first step by means of a movable brake plate until the brake plate moves.The brake system is then pressed against the brake line by further actuation of the brake system, with the fixed brake plate on the opposite side of the brake line, until the fixed brake plate touches the opposite side of the brake line. The brake plate is then squeezed to the brake line by further actuation, which results in braking. A slippage or wear of the moving brake plate is compensated directly by further actuation of the moving brake plate by the brake system.This final working position forms the basis for repositioning the brake body with the fixed brake plate. When the brake unit is opened, the reverse process takes place. The delivery device relaxes the brake plates, after which the brake body is repositioned with the fixed brake plate, starting from the final working position according to the set air gap of the fixed brake plate. This design allows the provision of a cost-effective braking unit, since a supply system alone controls the entire air gap and the wear compensation device adjusts the air gap of the fixed brake side, which can be achieved by simple means.

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The brake unit is guided along the brake line. The type of guidance defines, among other things, the required pass-through games and thus the required air gap. In an advantageous design, the brake unit includes a guidance support, which is guided directly along the brake line by means of a guide shoe, essentially free-flowing. The traction compensation device, preferably a mechanical traction compensation device, is located at a connection point between the guide support and the brake housing. This arrangement is advantageous because the brake unit is guided very precisely along the brake line and thus the air gaps required to balance guidance accuracies can be kept low. In this design, only the deviations from the track resulting from the joining of individual sections of track must be taken into account.Typically, this results in air gaps of 0.15 to 0.35 mm each. In a first version, the lift cab is guided along its road by means of its own lift guide shoes and a connecting point from the lift cab to the driver support transmits braking and/or restraint forces in a vertical direction and allows lateral balancing of driving accuracies. In a second embodiment, the lift cab is guided by means of the guide support of the braking system or by guide shoes integrated in this guide support and a connecting point from the lift cab to the guide support transmits lateral guides and brake and/or stop forces in a vertical direction.The cost is reduced as the cabin control functionality is integrated into the brake control.

In another version, the guide support is designed as part of the lift cab. The wear compensation device is located at a connection point between the guide support, or the lift cab and the brake housing. An air gap must be designed to accommodate the expected guidance deviations. This alternative usually requires a larger air gap than the previous versions, which results in a correspondingly longer delivery path or delivery time. These influences must be taken into account in the design of the brake system. In this version, in essence, both the track deviations resulting from the collision of individual rail sections must be taken into account, as well as the deviations resulting from the collision of individual rail sections, which typically occur as a result of the installation of bridges or bridges, for example, which are not affected by the deviations of the track, which typically occur in the case of a 0,75 mm vertical distance.

The mechanical wear compensation device shall contain at least one positioning component, a spring-shaped restraint and a sliding connection, for example a friction connection. The positioning component shall be located within the desired air gap between the steering support and the brake casing, sliding over a sliding connection and sliding further in the amount of wear expected in the extreme case. The positioning component shall be kept in a rest or standby position by the restraint, if no further forces are applied, which shall correspond to the unlocked or unlocked brake unit. The required sliding connection force is greater than the force generated by the restraint. When the fixed brake plate is actuated, the positioning part is moved in the air gap by the slide joint against the backing storage device in accordance with its free-moving glide path, which essentially corresponds to the air gap.

This simple mechanical wear compensation device is cheap to manufacture, easy to operate and reasonably safe.

Optionally, the wear compensation device allows the desired air gap to be adjusted, e.g. by means of an airfoil adjustment screw or nut.

The advantage of the guide support is that it has a holder which absorbs vertical brake forces directly from the brake liner or its mounting plate, which directs the vertical brake forces into the guide support and into the cabin and essentially relieves the brake body from vertical forces.

The following is a detailed description of the invention and of further embodiments by means of examples of embodiments relating to the figures.

It shows: Figure 1A diagram of a part of a lift system in a schematic side viewFig. 1A diagram of this lift systemFig. 2A diagram of a brake unit with a railway compensation device and a guide support integrated in the lift cabFig. 3A detailed description of an adjustable railway compensation deviceFig. 4Example of a railway compensation systemFig. 4.1A brake unit in a new state of rest (without railway compensation)Fig. 4.1aDetailed view of the railway compensation device in Fig. 4.1Fig. 4.2A brake unit in a new state of rest (without railway compensation)Fig. 4.2A detailed description of the railway compensation unit.Fig. 4.4A brake compensation unit is used in the direction of brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake brake

A possible overall arrangement of a lift system is shown in Fig. 1 and Fig. 1a. Fig. 1 shows the lift system 1 in a schematic side view and Fig. 1a shows the same lift system 1 in a schematic overview. The elevator system 1 shown includes a lift cabin 3 moving vertically in a shaft 2 along guideways 7. The lift cabin 3 is supported by loaders 5 and connected to a counterweight 4. Counterweight 4 and lift cabin 3 are driven by the loaders 5 by a drive 6 and move in the same direction in the lift shaft 2. The lift cabin 3 is equipped with a brake 11The brake unit 11 is installed below the body of the lift 3 in the example shown, but it is also possible to install it and/or above the lift cab 3. Of course, combinations of these are also possible. This would be particularly useful if several brake units 12 are used to increase braking performance. The lift cab is equipped with guide shoes 9In the example shown, the guideway 7 is formed by a T-shaped guideway which is also a brake track 8. Other forms of lifting systems are of course possible. A self-propelled lifting cabin, e.g. with a linear motor, may be used, the lift shaft may be partially open or separate tracks for driving (guideway 7) and braking (brake track 8) may be used.

Figure 2 shows a schematic of a lifting brake unit 12 as used in the lifting system 1 according to the invention, as shown in Figure 1. The brake unit 12 is mounted on the cab 3. The brake unit 12 comprises a brake housing 13, a movable brake plate 13 in relation to the brake housing 14 and a fixed brake plate 13 in relation to the brake housing 15. The brake plates 14,15 are connected to the brake line 8 by means of a fixing device 19 if necessary. The brake plates 14,15 are connected to the brake line 13 and the control line 19 by means of fixing plates 16 respectively. The brake line 8 shown in the example is the same as the guide line 7,where a conventional T-guidance rail is used. Brake unit 12 also contains a guide support 17. The guide support 17 is used to attach or connect the brake housing 13 to the cabin 3. It is firmly connected to cabin 3. A wear compensation device 30 is placed in the example shown between the guide support 17 and the brake housing 13. The guide support 17 also includes the guide shoe 9 which leads the lift cabin 3 along the guide track 7. The guide shoe 9 is held elastically to the cabin 3. This allows for isolation from guide vibrations. An elastic intermediate allows the cabin 3 vibration deviations (a) to the guide track 7, if the brake unit is set to a single airspeed, in this case the brake unit is set to a size ofthat, even in the event of a wobble in the cab under the steering elasticity (a) and any steering forces (f) and of displacement in the event of collision of steering components, the brake plate 14,15 shall not be in contact with the steering track 7 or track 8.

The wear compensation device 30 now maintains a fixed air gap (If) on the side of the fixed brake plate 15 essentially constant when the brake is ventilated. The brake unit 12 shown is further composed of electromechanical components. It contains a supply control 21 which maintains a given total air gap (It) constant. The total air gap (It) is formed by the sum of the fixed air gap (If) and the movable air gap (Ib), whereby the fixed air gap (If) corresponds to the side of the fixed brake plate 15 and the movable air gap (Ib) to the side of the movable brake plate 14. The fixed and movable brake controls are used only in this context.

The brake unit 12 is an electromechanical brake unit in which the movable brake liner 14 is delivered by means of an electromechanical drive such as a spindle drive. If necessary, the brake is operated via a gear step. The brake unit 12 preferably contains a brake control. This brake control can detect wear on the brake plate and/or deviations from normal behaviour of the brake unit 12 and the overall wear can be controlled by this method. In general, the wear compensation device 30 is adjusted so that the air gap (If) of the side of the fixed brake plate 15 is equal to an air gap (Ib) of the movable brake plate 14. It is therefore half the total air gap (It). This adjustment is appropriate if the lift is centrally suspended or centrally guided 3.

The brake support 17 also contains a bracket 18. The bracket 18 supports the brake plates 14,15 or the anchorage plates 16 and directs brake forces directly to the brake support 17 and on to the cabin 3. The brake casing 13 itself is thus relieved of the actual brake force, it only has to absorb the normal force acting in one direction which generates the brake force through friction.

Fig. 3 shows an adjustable wear compensation device 30 in detail. The wear compensation device 30 consists of a positioning part 31, a backing unit 32, a first stroke 33 and a second stroke 34. The wear compensation device 30 establishes a connection from the brake casing 13 to the guide support 17. In this embodiment, the positioning part 31 is connected to the guide support 17 via a slide connection 35. The positioning part 31 is preferably made of plastic. It can only be moved with a significant force of, say, about 25 N to 50 N relative to the guide support 17. The glazed part 31 itself is easily moved in the brake 13 position, thus allowing the guide support 13 to move to the second step.The first shift is directed towards the normal force. In a first shift the brake casing 13 can be pushed with a small force, sliding to the positioning part 31 - and thus also to the steering support 17 - with a small force. This sliding shift is limited by the first 33 stroke and the second stroke 34. This first shift corresponds to the desired air gap (If) of the fixed brake plate side.Other In a second shifting step, the brake lining 13 may be sliding together with the positioning part 31 to the control support 17.

Figures 4.1, 4.2, 4.3 and 4.4 show an example of the brake unit's working position and the details in Figures 4.1a, 4.2a, 4.3a and 4.4a show the corresponding position of the wear compensation device.

Fig. 4.1 and 4.1a show the brake unit 12 in the operating position, i.e. the brake is open. The brake linings 14.15 are spaced on either side of the brake line 8 around the air gap (If, Ib). The positioning part 31 of the wear compensation unit 30 is pressed against the first contact 33 defined by the air gap adjustment screw 36. The possible free movement or glide path of the positioning part 31 is adjusted according to the desired fixed air gap (If). In the case of an operation of the brake unit 12 the brake plate 14 is moved in a first step (S1) through the brake plate 19 to the brake plate 15 and then the brake plate 8 is moved through the brake plate 15 and then the brake plate 15 is moved in the opposite direction of the brake plate 15 (S 15 to S 152) to the brake plate 8 and the brake plate 15 is moved in the opposite direction of the brake plate.The brake plate 14.15 is then squeezed by another delivery motion to the brake line 8 and braking is achieved. This position is shown in Figures 4.2 and 4.2.a. The following is how the air play is now compensated in the wear compensation unit 30. A wear or tear of the movable brake plate 14 is now directly compensated, as shown in Figures 4.3 and 4.3a, by a further delivery of the movable brake plate 14 by the delivery device 19; a compensation of wear (v) of the fixed brake plate 15 is indirectly compensated by the delivery device 19 by further delivery (S3) or pulling of the brake body 13 with the fixed brake plate 15 and this delivery of the brake body 13 causes a slip in the slip joint 35 between brake body 13 and guide port 17 in the displacement compensation device 30 as the slide of the positioned brake 31 is already used.The brake lining 13 is thus positioned with the fixed brake plate 15 to form the final working position of the fixed brake lining 15 in this brake sequence, which is necessarily the basis for the brake lining 13 to be repositioned with the fixed brake plate 15. When the brake unit 12 is opened, the reverse process of the condition described in Figures 4.4 and 4.4a takes place in the same way. The service unit 19 relaxes the brake plates 14.15 and then the brake casing 13 is repositioned together with the fixed brake plate 15 starting from the final working position according to the adjusted air gap (If) of the fixed brake plate 15 (S4).The brake system is then moved to the control to the right of the control, which pushes the brake body 13 against the positioning part 31 according to the set airway (If) to the first contact 33. As shown in Figure 4.4a, the positioning part 31 now slides around the wear amount (v) against the guide support 17. The fixed brake plate 15 has reached its air gap (If) and the movable brake plate 14 can now be retracted by the remaining amount of the entire air gap (Ib=It-If). The brake unit is ready for the next brake and the brake lines are in the new condition. This allows operating times to be maintained as they were for the new brake liners.

Fig. 5 shows a schematic view of a brake unit with wear compensation device and lift cabin guidance integrated into the brake unit. The guide support 17 is directed by a guide shoe 9 along the brake and guide track 7.8, while the cabin 3 is attached to the guide support 17 via an elastic element 10, for example a rubber spring, a damper or an active vibration damping. The function of the brake unit 11 itself is similar to the previous representations. The advantage of this solution is that the air gap can be made smaller, since a cabin vibration does not have to be taken into account.

Fig. 6 shows a schematic view of a brake unit with wear compensation device and separate guidance for brake unit and lift cab. The guide support 17 is directed by a guide shoe 9 along the brake and guide track 7,8 and the cab 3 is directed by its own guide elements (not shown). The function of the brake device 11 itself corresponds to the previous representations. The advantage of this solution is that the air gap (If) can also be made smaller, since a swing path of the cab 3 does not have to be taken into account and a design of the guide shoe 9 of the brake can be done independently from the cab 3.

Fig. 7 shows another schematic example of a brake unit with wear compensation device 30. The control support 17 is attached to the cabin 3, the brake housing 13 is connected to the control support 17 via the positioning part 31 and a load bearing ball 37. The load bearing ball 37 is appropriately part of the control support 17. The brake housing 13 is slidingly displaced on the hollow positioning part 31, with the displacement on the positioning part 31 being controlled by a sliding limiter which can be adjusted by means of a fan-set force or air-playing ball 36 to the desired position, the return unit 32 is limited to the air-setter 33 in the reverse direction at the first position of the brake unit 19.In the case of wear (v), the positioning part 31 may slip on the support beam 37 which results in wear compensation as explained in Figure 4 series. Two such support beam arrangements are preferably stacked on top of each other, which also allows braking forces to be transmitted directly. The slide connection 35 is solved in this example at a particularly low cost.Other The friction-based slide connection 35 shown could be replaced by restraint connections.

Figure 8 shows a brake unit as shown in Figure 7 with an integrated bracket. The guide support 17 shown in Figure 7 is fitted with a bracket 18 which directly supports the brake plates 14, 15 when braking and thus directs brakes and restraint forces into the guide support 17.

Fig. 9 shows another schematic example of a brake unit with wear compensation device and support bolts. The brake casing 13 is also connected to the guide support 17 as explained in Fig. 7 via the positioning part 31 and support bolts 37. The support bolt 37 is in a sense part of the guide support 17. The brake casing 13 is slidingly adjustable on the hollow positioning part 31. The displacement on the positioning partition 31 is provided by a sliding limit which is set by means of a fan-set screw or air-screw-screw-screw-screw-screw according to the desired positioning (if any) The air-screw-screw-screw is also included. The functional limitation is also integrated in the positioning partition 31 which corresponds to the positioning position of the brake.

The design of the guide shoe may be made using known technologies. In particular, a sliding guide shoe or a rolling guide shoe may be used. The guide shoe may contain a system of air speed measurement, the operating speed of which may be determined by means of a thoracic device suspended from the cable. This information may be used, for example, by means of a thoracic device or by means of a thoracic air regulator (if possible, by using a servo-controller).

Claims (16)

1. Lift installation (1) with a lift cage (3), which moves in vertical direction along guide tracks (7) and which in the case of need is braked or held at standstill by a braking equipment (11), the braking equipment (11) comprises at least two brake units (12), wherein each of the brake units (12) comprises a brake lining (14, 15) which in the case of need co-operates with a brake surface, which is associated with this brake lining, of a brake track (8), characterised in that at least one of the brake units (12) comprises a wear-compensating device (30) which on release of this brake unit (12) sets a clearance (If), which arises between the brake lining (14, 15) and the associated brake surface of the brake track (8), in correspondence with a substantially constant value.
2. Lift installation according to claim 1, characterised in that the brake unit (12) comprises a brake housing (13), a brake plate (14) movable with respect to the brake housing (13) and a brake plate (15) fixed with respect to the brake housing (13) and that the brake plates (14, 15) in the case of need can be brought into contact with the brake track (8) by means of an advance device (19) and that the wear-compensating device (30) keeps the clearance (If) on the side of the fixed brake plate (15) substantially constant and the advance device (19) keeps a total clearance (It) constant.
3. Lift installation according to claim 2, characterised in that the advance device (19) comprises an electromechanical spindle drive, wherein the spindle is in case of need actuated by way of a gear stage.
4. Lift installation according to one of claims 2 and 3, characterised in that the brake unit (12) consists of electromechanical components and comprises advance regulating means (21), by means of which a predetermined total clearance (It) can be set, and the electromechanical brake unit (12) comprises advance checking means by means of which brake plate wear and/or departures from normal behaviour of the brake unit (12) can be ascertained.
5. Lift installation according to any one of claims 2 to 4, characterised in that the total clearance (It) corresponds with twice the amount of the fixed clearance (If) on the side of the fixed brake plate (15).
6. Lift installation according to any one of the preceding claims, characterised in that the lift installation (1) comprises a guide rail (7, 8) which is at the same time the guide track (7) and brake track (8).
7. Lift installation according to any one of the preceding claims, characterised in that the brake unit (12) comprises a guide support (17) and the mechanical wear-compensating device (30) is arranged at a connecting point between the guide support (17) and the brake housing (12), wherein the guide support (17) is guided along the brake track (8) substantially free of play by means of a guide shoe (9) or the guide support (17) is fixedly connected with the lift cage (3) or is a component of the lift cage (3), wherein the lift cage (3) is guided along the guide track (7) by means of a guide shoe (9).
8. Lift installation according to claim 7, characterised in that the guide shoe (9) is a sliding guide shoe and/or the guide shoe (9) comprises a guide roller and/or the guide shoe (9) comprises a measuring system by way of which a travel speed of the braking equipment (11) or of the cage (3) can be determined.
9. Lift installation according to one of claims 7 and 8, characterised in that the guide support (17) comprises a holder (18), which accepts vertical braking forces in the brake lining (14, 15) or the fastening plate (16) thereof, introduces the vertical braking forces into the guide support (17) and into the cage (3) and substantially relieves the brake housing (13) of vertical forces.
10. Lift installation according to claim 9, characterised in that the brake plates (14, 15) are connected with the brake housing (13) or advance device (19) by means of a fastening plate (16) and this fastening plate (16) forms together with the holder (18) a support point which enables introduction of vertical braking forces from the brake plate (14, 15) into the holder (18), the brake housing (13) being relieved of vertical braking forces, and which at the same time enables horizontal advance of the brake lining (14, 15) towards the brake track (8).
11. Lift installation according to any one of the preceding claims 7 to 10, characterised in that the wear-compensating device (30) comprises a positioning part (31), which is connected by way of a slip connection (35) or detent connection with the brake housing (13) or the guide support (17) and which is mutually connected by way of a slide connection with the guide support (17) and the brake housing (13), wherein the slide connection enables relative sliding between the brake housing (13) and the guide support (17) in correspondence with the desired clearance (If) and a relative slipping in the slip connection takes place when this clearance (If) is exceeded.
12. Lift installation according to any one of the preceding claims, characterised in that the wear-compensating device (30) enables setting of the desired fixed clearance (If).
13. Lift installation according to claim 11, characterised in that the brake housing (13) is urged by means of a restoring unit (32), preferably a spring, in the direction of the fixed brake plate (15), wherein the restoring unit (32) is arranged between brake housing (13) and positioning part (31), between positioning part (31) and guide support (17) or between brake housing (13) and guide support (17) and wherein a restoring force produced by the restoring unit (32) is less than a slip resistance force produced in the slip connection (35), but the restoring force produced by the restoring unit (32) is greater than the slide resistance force produced in the slide connection.
14. Lift installation according to claim 4, characterised in that the movement of the movable brake plate (14) is carried out by an advance device (9) regulated by way of the advance regulating means (21) and the advance device moves the brake plate (14) directly perpendicularly to the brake surface.
15. Lift installation according to any one of the preceding claims, characterised in that the braking equipment (11) is arranged at the lift cage (3) and the brake units (12) are attached below and/or laterally of and/or above a cage body and the brake units (12) in case of need act on the guide track (7).
16. Method of braking and holding a lift cage, the lift cage (5) being a component of a lift installation (1) and moved along guide tracks (7), the lift cage (3) in the case of need being braked or held at standstill by braking equipment (11) and the braking equipment (11) comprising at least two brake units (12), wherein each of the brake units (12) comprises a brake lining (14, 15) which in the case of need co-operates with a brake surface, which is associated with this brake lining, of a brake track (8), characterised in that a clearance (If) arising between the brake lining (14, 15) and the associated brake surface of the brake track (8) on release of at least one of the brake units (12) is adjusted by means of a wear-compensating device (30) in correspondence with a substantially constant value.