Hydraulic safety brake or clutch

Abstract

The invention relates to a hydraulic brake, clutch or clutch-brake combination for a work machine, which is designed to be switchable by means of a hydraulic medium delivered by a hydraulic pump (18), with a rotor disk (4) arranged on a shaft in a rotationally fixed but axially displaceable manner and a counterpart (15) cooperating therewith, wherein the counterpart (15) is mounted axially displaceably in relation to the rotor disk (4), with a mechanical force transmitter (17) designed to apply force to the counterpart (15) in the axial direction, and with a hydraulic piston (13) provided by a cylinder-piston arrangement (12), which is designed to be movable in the axial direction and is designed to act on the counterpart (15) in the event of pressure being applied with hydraulic medium delivered by the hydraulic pump (18) in a manner counter to the force applied by the force transmitter (17), characterized in thatthat the hydraulic pump (18) fluidically interacts with a reservoir (20) accommodating hydraulic fluid, wherein the hydraulic pump (18) and the reservoir (20) are designed for intended use exclusively with the cylinder-piston arrangement (12), and that a bypass line (24) is provided which fluidically bypasses the hydraulic pump (18) and fluidically connects the reservoir (20) to the cylinder-piston arrangement (12), wherein an electrically switchable valve (25) is integrated into the bypass line (24) and is designed to open the bypass line (24) in the event of a de-energized position of the valve (25).

Description

[0001] The invention relates to a hydraulic brake, clutch or clutch-brake combination for a work machine, which is designed to be switchable by means of a hydraulic medium delivered by a hydraulic pump, with a rotor disk arranged on a shaft in a rotationally fixed but axially displaceable manner and a counterpart interacting therewith, wherein the counterpart is mounted axially displaceably in relation to the rotor disk, with a mechanical force transmitter which is designed to apply force to the counterpart in the axial direction, and with a hydraulic piston provided by a cylinder-piston arrangement, which is designed to be movable in the axial direction and is designed to act on the counterpart in the event of pressure being applied with hydraulic medium delivered by the hydraulic pump, counter to the force applied by the force transmitter.In particular, the invention relates to a safety brake, clutch or clutch-brake combination.

[0002] A hydraulic brake or clutch for a work machine of the generic type is known, for example, from DE 10 2004 025 296 A1.

[0003] A brake or clutch of this type is actuated by means of a hydraulic fluid supplied by a hydraulic pump. In the case of a safety brake, the application of hydraulic force causes the brake to be released, i.e., opened. In the case of a safety clutch, the brake is closed hydraulically.

[0004] The brake or clutch has a rotor disk that is mounted on a shaft in a rotationally fixed yet axially movable manner. The rotor disk can therefore rotate along with the shaft and is thus mounted on the shaft in a rotationally fixed manner. For engaging the brake or clutch, the rotor disk is mounted longitudinally along the shaft, i.e., axially movable. When engaged, the rotor disk moves relative to the shaft, in the longitudinal direction of the shaft, i.e., axially.

[0005] The brake or clutch also has a counterpart that interacts with the rotor disk. This counterpart can be designed, for example, as a pressure plate.

[0006] The counterpart is mounted so that it can be axially displaced in relation to the rotor disk and can therefore be moved in the axial direction towards the rotor disk or away from it in the opposite direction.

[0007] Furthermore, a mechanical force sensor is provided, for example, in the form of a compression spring or a plurality of compression springs. The force sensor is designed to apply force to the counterpart in the axial direction. In the case of a safety brake, the force sensor applies force to the counterpart in the direction of the rotor disk; in the case of a safety clutch, the force sensor applies force in the opposite direction.

[0008] The brake or clutch also features a hydraulic piston provided by a cylinder-piston assembly. This piston is designed to be axially movable and, when pressurized with hydraulic fluid delivered by the hydraulic pump, is configured to act on the counterpart in a manner counter to the force applied by the force transducer. When the hydraulic piston is pressurized with hydraulic fluid, the counterpart is moved in an axial direction, counter to the force applied by the mechanical force transducer.

[0009] In the case of a safety brake, the brake is closed due to the force provided by the mechanical force transmitter. In this closed position, the counterpart acts on the rotor disc and locks it, including the shaft that is rigidly connected to it. When the hydraulic piston is pressurized with hydraulic fluid as intended, the brake is released. In this case, the hydraulic piston acts on the counterpart against the force provided by the force transmitter, causing it to move axially away from the rotor disc. The rotor disc is then released, allowing it to rotate, including the shaft that is rigidly connected to it.

[0010] In the case of a safety clutch, the mechanism described above for a safety brake is reversed. The clutch is opened by the force provided by the mechanical force transmitter. The clutch is closed when hydraulic fluid is applied to the hydraulic piston, causing the counterpart to move axially toward the rotor disk, counter to the force of the force transmitter.

[0011] Although the brake or clutch described above has proven itself in everyday practical use, there is room for improvement. In particular, the connection to hydraulic lines required for the intended use of the brake or clutch is perceived as disadvantageous, especially in the case of original equipment. Another disadvantage is that controlling the brake or clutch during normal operation is comparatively complex and requires corresponding additional devices. Therefore, the object of the invention is to propose a hydraulic brake or clutch of the generic type whose design has been further developed to allow simplified handling, both with regard to original equipment and with regard to control during normal use.

[0012] To achieve this object, the invention proposes a hydraulic brake, clutch or clutch-brake combination, in particular a safety brake, clutch or clutch-brake combination of the type mentioned at the outset, which is characterized in that the hydraulic pump fluidically interacts with a reservoir accommodating hydraulic fluid, wherein the hydraulic pump and the reservoir are designed for intended use exclusively with the cylinder-piston arrangement, and that a bypass line is provided which fluidically bypasses the hydraulic pump and fluidically connects the reservoir to the cylinder-piston arrangement, wherein an electrically switching valve is integrated into the bypass line and is designed to open the bypass line in the event of a de-energized position of the valve.

[0013] According to a first aspect of the invention, a reservoir is provided for storing hydraulic fluid. This reservoir is fluidically connected to the hydraulic pump. When used as intended, hydraulic fluid provided by the reservoir can be pumped by the hydraulic pump and transferred to the cylinder-piston assembly to pressurize the hydraulic piston. The hydraulic pump and the reservoir thus interact fluidically.

[0014] The hydraulic pump and the reservoir are designed for intended use exclusively of the cylinder-piston arrangement. "Exclusively" in the sense of the invention means that the hydraulic pump and the reservoir are dimensioned, i.e. designed, in such a way that proper operation of the cylinder-piston arrangement of the affected safety brake or clutch is possible. The hydraulic pump and the associated reservoir are therefore not designed to be able to operate cylinder-piston arrangements of multiple safety brakes or clutches equally. In this case, the hydraulic pump and the reservoir are designed with reference to the safety brake or clutch in particular such that the operating pressure required during proper operation can be generated and applied to the hydraulic piston of the cylinder-piston arrangement.

[0015] Hydraulic assemblies are known from the prior art that are designed to operate a plurality of cylinder-piston assemblies, i.e., a plurality of safety brakes or clutches, equally. In contrast, the invention proposes a design based on the cylinder-piston assembly of a safety brake or clutch being assigned a hydraulic pump including a reservoir. The hydraulic pump and the associated reservoir serve exclusively to enable the cylinder-piston assembly assigned to them to operate as intended.When several safety brakes or clutches are used simultaneously, a number of separately operated hydraulic pumps including reservoirs corresponding to the number of safety brakes or clutches used are used, with one hydraulic pump including reservoir being provided for each safety brake or clutch.

[0016] According to a second aspect of the invention, a bypass line is provided that fluidically surrounds the hydraulic pump. This bypass line fluidically connects the reservoir to the cylinder-piston assembly. Thus, a direct fluidic connection is provided between the cylinder-piston assembly and the reservoir via the bypass line, i.e., a fluidic connection without the interposition of the hydraulic pump.

[0017] An electrically controlled valve is integrated into the bypass line. This valve is designed to open the bypass line if the valve is de-energized.

[0018] So, if the electrically switching valve is energized, the bypass line is closed. In this case, hydraulic fluid can only be introduced into the cylinder-piston arrangement via the hydraulic pump. If the valve is de-energized, either actively by switching the valve or in the event of a power failure, the valve switches to the open position, which opens the bypass line. In this open position of the valve, hydraulic fluid can be transferred from the cylinder-piston arrangement back into the reservoir, bypassing the hydraulic pump. As a result of this re-transfer, the corresponding hydraulic piston in the cylinder-piston arrangement is de-energized, so that force is applied to the counterpart only by the force sensor and no longer by the hydraulic piston.

[0019] The inventive design makes it possible to control a hydraulically operated brake, clutch, or clutch-brake combination purely electrically. For proper installation, it is not necessary to connect the brake, clutch, or clutch-brake combination to hydraulic lines. The self-contained design of the brake, clutch, or clutch-brake combination with its own hydraulic pump and reservoir makes it possible to pre-assemble the brake, clutch, or combination. The actual connection or installation on site is then carried out simply by electrically connecting the hydraulic pump and the electrically switching valve to an electrical power supply.

[0020] The embodiment according to the invention therefore proposes a brake, clutch or clutch-brake combination which operates entirely hydraulically but can nevertheless only be connected electrically, thus an electro-hydraulically operating brake, clutch or clutch-brake combination.

[0021] Electromagnetically operated brakes or clutches are already known from the prior art. However, in contrast to the design according to the invention, these have the disadvantage of only being able to transmit lower torques for the same size. The design according to the invention therefore offers the advantage that, due to the hydraulic operating principle, high torques can be transmitted, but at the same time, with a much more compact design compared to conventional hydraulic brakes or clutches. The design according to the invention therefore achieves the synergistic effect of, on the one hand, transmitting high torques due to hydraulic reasons and, on the other hand, enabling simplified handling, particularly during initial commissioning and during intended use with regard to control.

[0022] According to a further feature of the invention, the hydraulic pump comprises an electric motor. The electric motor drives the actual pumping device, by means of which, during intended use, hydraulic fluid is pumped from the reservoir and transferred to the cylinder-piston assembly. Therefore, no external hydraulic fluid is supplied. Rather, the hydraulic fluid is guided in a closed circuit on the brake, clutch, or combination side and, when required, is pumped into a working chamber provided by the cylinder-piston assembly by means of the electrically operated hydraulic pump to build up the appropriate hydraulic pressure. Therefore, for the hydraulic pump to be connected for its intended use, it is advantageously only necessary to connect the electric motor to a power supply.

[0023] According to a further feature of the invention, it is provided that the electric motor and the electrically switching valve are connected to a common control device in terms of signaling.

[0024] The control unit of the brake, clutch, or combination is used to control or regulate both the electric motor and the electrically switching valve. For this purpose, both the electric motor and the electrically switching valve are connected to the common control unit via signals.

[0025] When used as intended, the control device ensures that the electric motor, and thus the hydraulic pump, operates when the valve is closed. This allows the appropriate pressure to build up in the working chamber of the cylinder-piston assembly, resulting in the intended engagement of the brake, clutch, or clutch-brake combination. It is not necessary to operate the electric motor continuously. Rather, the electric motor can be switched off once the desired hydraulic pressure is reached. The system then maintains this pressure, provided, of course, that the entire system is designed to be low-leakage or leak-free.

[0026] If the brake, clutch, or clutch-brake combination is to be reactivated by reducing the hydraulic pressure, both the electric motor of the hydraulic pump and the electrically switching valve must be de-energized via the control unit. As a result, the bypass line opens, and pressure can be reduced within the working chamber of the cylinder-piston assembly by discharging hydraulic fluid in the working chamber via the bypass line toward the reservoir.

[0027] A further particular advantage of this arrangement is that the safety function of the brake, clutch, or clutch-brake combination is still maintained. This is because, in the event of a defect, the brake, clutch, or clutch-brake combination switches, whether due to a hydraulic system fault, for example due to a leak, or due to a power failure. In the event of a power failure, an immediate reduction in the pressure applied to the counterpart on the hydraulic piston side is achieved by hydraulic fluid flowing from the working chamber of the cylinder-piston arrangement into the reservoir, so that in the case of a brake, an immediate closing takes place and in the case of a clutch, an immediate opening takes place. In this respect, the brake, clutch, or clutch-brake combination according to the invention can also be referred to as a safety brake, clutch, or clutch-brake combination.

[0028] According to a further feature of the invention, it is provided that the control device, the electrically switching valve, the reservoir and the hydraulic pump are encapsulated and accommodated in a common housing.

[0029] According to this particularly preferred embodiment, a particularly compact design is achieved. The individual components of the hydraulic unit, i.e. the control device, the electrically switching valve, the reservoir and the hydraulic pump, are combined into a separate assembly and housed in a housing provided for this purpose. In this respect, an encapsulated design is achieved. This assembly is preferably pre-designed by the manufacturer and arranged on a safety brake or clutch for the intended use thereof. On the user side, it is then advantageously only necessary to connect the safety brake or clutch to signal lines for the control device on the one hand and to an electrical power supply for the electric motor of the hydraulic pump and the electrically switching valve.Although the safety brake or clutch operates hydraulically, the user only needs to connect the signal and power lines to the safety brake or clutch as original equipment. A hydraulic connection is completely eliminated, which not only simplifies handling but also greatly simplifies control.

[0030] According to a further feature of the invention, connections accessible on the outside of the housing are provided for a signal connection of the control device, on the one hand, and for an electrical connection of the electric motor and the electrically switching valve. For proper installation of the safety brake or clutch according to the invention, the user only needs to connect the corresponding connecting cables to the connections accessible on the outside of the housing.

[0031] According to a further feature of the invention, the housing, which accommodates the control device, the electrically switching valve, the reservoir, and the hydraulic pump, is designed as a housing part of a housing accommodating the brake or clutch. Accordingly, the entire hydraulic unit of the inventive design is designed as an integral component of the safety brake or clutch. This results in a particularly compact overall design.

[0032] As an alternative to the previously described configuration, the housing accommodating the control device, the electrically switching valve, the reservoir, and the hydraulic pump can be designed as a separate housing from the housing of the safety brake or clutch, which is arranged on the housing of the safety brake or clutch. This configuration offers the particular advantage of being able to retrofit existing hydraulic safety brakes or clutches.

[0033] According to a further feature of the invention, it is provided that the hydraulic pump is fluidly connected to the cylinder-piston arrangement by means of a hydraulic line, wherein a check valve is integrated into the hydraulic line.

[0034] The check valve advantageously ensures that hydraulic fluid does not flow unintentionally from the working chamber of the cylinder-piston assembly back into the hydraulic pump and / or the reservoir. Thanks to the check valve, the electric motor can be switched off when sufficient hydraulic pressure has built up, without the risk of hydraulic fluid being recirculated. This minimizes power consumption when the safety brake or clutch is used as intended.

[0035] According to a further feature of the invention, it is provided that the storage container provides a storage volume of < 500 ml, preferably < 400 ml, even more preferably < 300 ml.

[0036] Since the hydraulic unit according to the invention is designed to be self-contained and, moreover, has dimensions designed exclusively for the intended operation of the cylinder-piston assembly of a safety brake or clutch, the storage volume provided by the reservoir can be correspondingly small. This is advantageous, particularly for environmental reasons, and also in terms of simplified handling and operating costs.

[0037] The inventive design provides an overall closed system. A hydraulically operating safety brake or clutch is equipped with a hydraulic unit whose design enables the intended operation of only the associated brake or clutch. Thus, a hydraulically operating brake or clutch is proposed that is equipped with a hydraulic unit tailored specifically for this brake or clutch. The entire arrangement is preferably encapsulated so that a subsequent user cannot fundamentally determine that it is a hydraulically operating brake or clutch. The hydraulic unit is controlled by an electric motor, so that only one connection for the corresponding signal lines is required, but not for hydraulic lines, even though the brake or clutch operates purely hydraulically.A subsequent user of the brake or clutch according to the invention therefore only has to worry about the electrical control or provide appropriate equipment for this.

[0038] The result of this design is particularly advantageous in a compact design while simultaneously providing high transmittable torques and the possibility of being able to effect precise regulation or control.

[0039] The safety function of the brake or clutch according to the invention is advantageously still maintained. This is because, as already described, a bypass line is provided, into which an electrically switching valve is integrated, which opens automatically in an emergency, i.e., if the power supply fails. When the valve is opened, the hydraulic counterforce collapses, so that the force transducer acting on the counterpart automatically transfers the brake to the braking position or the clutch to the disengaged position.

[0040] Further features and advantages of the invention will become apparent from the following description with reference to the figures. Fig. 1 in a schematic sectional view of an embodiment according to the invention using the example of a safety brake and Fig. 2 shows a schematic representation of the function.

[0041] Fig. 1 shows a schematic sectional view of an embodiment according to the invention using a safety brake 1.

[0042] The safety brake 1 is designed in a manner known per se and has a hydraulic unit 2 according to the invention, which is described in detail in Fig. 2 is shown.

[0043] The safety brake 1 has a rotatable rotor disc 4, which is rotationally fixed on a Fig. 1 is arranged on a shaft not shown in detail. The arrangement of the rotor disk 4 on the shaft is rotationally fixed, yet axially displaceable, for which purpose a hub 3 is used. For the purpose of axially displaceable arrangement, a toothing 5 acting between the hub 3 and the rotor disk 4 is provided.

[0044] The rotor disc 4 carries friction linings 6 on both sides. As an alternative to this embodiment, separate friction discs or plates equipped with friction linings 6 can also be provided.

[0045] The safety brake 1 further comprises a stationary housing 7. This housing 7 comprises two housing parts 8 and 10, which are spaced apart from one another by means of a spacer 9 and are connected to one another by means of screws 11.

[0046] The housing part 8 also acts as a cylinder in a cylinder-piston arrangement 12. A hydraulic piston 13 is axially movable within the cylinder 8. This piston forms a working chamber 14 in operative connection with the cylinder 8.

[0047] A counterpart 15 in the form of a pressure plate is connected to the hydraulic piston 13. Corresponding screws 16 are used to position the counterpart 15 on the hydraulic piston 13.

[0048] The housing part 8, which serves as a cylinder, also provides recesses into which springs serving as force transducers 17 are inserted. These force transducers 17 act on the counterpart 15 connected to the hydraulic piston 13.

[0049] In the closed position of the safety brake 1, the force sensors 17 act on the counterpart 15 and press this, together with the hydraulic piston 13 connected to it, axially in the direction of the housing part 10 serving as an abutment plate. As a result, the rotor disk 4 arranged between the housing part 10 and the counterpart 15 is fixed, and thus also a shaft that supports the rotor disk 4 in a rotationally fixed manner.

[0050] To open the safety brake 1, ie to transfer the safety brake 1 from the previously described braking position into a Fig. 1, hydraulic fluid is to be introduced into the working chamber 14 by means of the hydraulic unit 2. As a result, the hydraulic piston 3 is displaced axially, with reference to the drawing plane according to Fig. 1 to the right. The counterpart 15 connected to the hydraulic piston 13 is consequently moved, resulting in an increased spacing between the counterpart 15 and the housing part 10, with the result that the rotor disk 4 is released, allowing a rotational movement of the same. This open position of the safety brake 1 is in Fig. 1 shown.

[0051] The hydraulic unit 2 serves exclusively to actuate the cylinder-piston arrangement 12 of the one in Fig. 1 shown safety brake 1. It is dimensioned accordingly and is not designed to be able to operate other cylinder-piston arrangements of other safety brakes in the same way.

[0052] As can be seen from the illustration Fig. 2, the hydraulic unit 2 has a hydraulic pump 18, which is operable via an electric motor 19. The hydraulic pump 18 is fluidly connected to a reservoir 20 via a hydraulic line 21. Via a further hydraulic line 22, the hydraulic pump is fluidly connected to the safety brake 1, i.e., to the working chamber 14 of the previously described cylinder-piston arrangement 12. A check valve 23 is integrated into the hydraulic line 22.

[0053] As can be seen from the illustration Fig. 2, a bypass line 24 is provided that bypasses the hydraulic pump 18. This bypass line fluidly connects the cylinder-piston assembly 12 of the safety brake 1 with the reservoir 20. An electrically switching valve 25 is integrated into this bypass line 24.

[0054] The hydraulic unit 2 further comprises a control device 26. This is in signal connection both with the electrically switching valve 25 and with the electric motor 19 of the hydraulic pump 18, for which purpose corresponding signal lines 27 and 28 are provided.

[0055] The control device 26 is further connected to a connecting line 29, via which access to the control device 26 is possible from outside.

[0056] The electrically switching valve 25 and the electric motor 19 are also connected to an electrical power supply, which is Fig. 2 is not shown in detail.

[0057] The inventive design enables operation as follows:

[0058] To release the safety brake 1, hydraulic fluid must be introduced into the working chamber 14 of the cylinder-piston arrangement 12 in the manner already described. For this purpose, the control device 26 controls both the electrically switching valve 25 and the electric motor 19, whereupon they are energized. As a result, the bypass line 24 is closed by the switched valve 25, and the hydraulic pump 18 generates a corresponding hydraulic pressure in the working chamber 14 by means of the electric motor 19 provided for this purpose. If the hydraulic system is sufficiently tight, it is not necessary for the electric motor 19 to operate continuously to maintain the pressure. Rather, the one-time sufficient pressure buildup by the electric motor 19 is sufficient.

[0059] As a result of the development of hydraulic pressure, the hydraulic piston 13 moves in the manner already described, with the result that the rotor disk 4 is released.

[0060] To close the safety brake 1, valve 25 must be opened. For this purpose, valve 25 must be de-energized. Furthermore, the electric motor 19 must be de-energized so that no pressure is applied.

[0061] When the valve 25 is open, the working chamber 14 is depressurized to such an extent that the hydraulic fluid contained therein can flow back into the reservoir 20 via the bypass line 24 and the open valve 25. As a result, the force transducer 17 returns the hydraulic piston to the braking position.

[0062] The safety function of the safety brake 1 is ensured both hydraulically in the manner already described, and electrically, since in the event of a power failure the valve 25 opens automatically, whereby the safety brake 1 is returned to its braking position.

[0063] The embodiment according to the invention is based on the Fig. 1 and Fig. 2 using the example of a safety brake 1. A safety clutch is designed to have the same effect in reverse. Reference symbol 1 safety brake 2 hydraulic units 3 Hub 4 rotor disc 5 Gearing 6 Friction lining 7 housings 8 Housing part (cylinder) 9 Spacer 10 Housing part (abutment plate) 11 Screw 12 cylinder-piston arrangement 13 hydraulic pistons 14 Workspace 15 Counterpart (pressure plate) 16 Screw 17 Force sensor (spring) 18 Hydraulic pump 19 Electric motor 20 storage containers 21 Hydraulic line 22 Hydraulic line 23 Check valve 24 Bypass line 25 Valve 26 Control device 27 Signal line 28 Signal line 29 Connection cable QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2004 025 296 A1

[0002]

Claims

[1] A hydraulic brake, clutch or clutch-brake combination for a work machine, which is designed to be switchable by means of a hydraulic medium delivered by a hydraulic pump (18), with a rotor disc (4) arranged on a shaft in a rotationally fixed but axially displaceable manner and a counterpart (15) cooperating therewith, wherein the counterpart (15) is mounted axially displaceably in relation to the rotor disc (4), with a mechanical force transmitter (17) designed to apply force to the counterpart (15) in the axial direction, and with a hydraulic piston (13) provided by a cylinder-piston arrangement (12), which is designed to be movable in the axial direction and is designed to act on the counterpart (15) in the event of pressure being applied with hydraulic medium delivered by the hydraulic pump (18) in a manner counter to the force applied by the force transmitter (17), characterized byin that the hydraulic pump (18) fluidically interacts with a reservoir (20) accommodating hydraulic fluid, wherein the hydraulic pump (18) and the reservoir (20) are designed for intended use exclusively with the cylinder-piston arrangement (12), and in that a bypass line (24) is provided which fluidically bypasses the hydraulic pump (18) and fluidically connects the reservoir (20) to the cylinder-piston arrangement (12), wherein an electrically switchable valve (25) is integrated into the bypass line (24) and is designed to open the bypass line (24) in the event of a de-energized position of the valve (25). [2] Brake, clutch or clutch-brake combination according to claim 1, characterized by that the hydraulic pump (18) has an electric motor (19). [3] Brake, clutch or clutch-brake combination according to claim 2, characterized bythat the electric motor (19) and the electrically switching valve (25) are connected to a common control device (26) for signaling purposes. [4] Brake, clutch or clutch-brake combination according to claim 3, characterized by that the control device (26), the electrically switching valve (25), the reservoir (20) and the hydraulic pump (18) are encapsulated and accommodated in a common housing. [5] Brake, clutch or clutch-brake combination according to claim 4, characterized by that connections accessible on the outside of the housing are provided for a signal connection of the control device (26) on the one hand and for an electrical connection of the electric motor (19) and the electrically switching valve (25) on the other hand. [6] Brake, clutch or clutch-brake combination according to claim 4 or 5, characterized bythat the housing accommodating the control device (26), the electrically switching valve (25), the reservoir (20) and the hydraulic pump (18) is designed as a housing part of a housing accommodating the brake or the clutch. [7] Brake, clutch or clutch-brake combination according to claim 4 or 5, characterized by that the housing accommodating the control device (26), the electrically switching valve (25), the reservoir (20) and the hydraulic pump (18) is designed as a separate housing from a housing accommodating the brake or the clutch, which is arranged on the housing of the brake or clutch. [8] Brake, clutch or clutch-brake combination according to one of the preceding claims, characterized by that the hydraulic pump (18) is hydraulically connected to the cylinder-piston arrangement (12) by means of a hydraulic line (22), wherein a check valve (24) is integrated into the hydraulic line (22). [9] Brake, clutch or clutch-brake combination according to one of the preceding claims, characterized by that the storage container (20) provides a storage volume of < 500 ml, preferably < 400 ml, even more preferably < 300 ml.

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