EP4501544A2 - Clamping or gripping device with integrated fluid drive - Google Patents

Abstract

The invention relates to a clamping and/or gripping device (10) comprising:- a base housing (12) with a central longitudinal axis (14),- a clamping element (16) mounted in the base housing (12) so as to be displaceable radially to the central longitudinal axis (14),- a fluid drive (26) for driving the at least one clamping element (16),wherein the fluid drive (26) is arranged in or on the base housing (12).

Description

The invention relates to a clamping and/or gripping device, in particular a chuck and/or a zero-point clamping module, for clamping and/or gripping components and/or component carriers.

Clamping systems are known from the state of the art which are driven by an external, in particular hydraulic or pneumatic, energy source. Such clamping systems require complex cable laying to the clamping system, in particular in multi-axis machining centers or systems. In addition, such clamping systems have leakage losses and poor efficiency.

Electromechanical clamping systems are also known from the prior art, which have an electric motor with a downstream gear and a spindle drive. Such clamping systems have little structural flexibility, since the drive unit must always be arranged in the force flow of the clamping system.

The invention is based on the object of providing a clamping and/or gripping device which has a simple and flexible construction and low operating costs.

The object underlying the invention is achieved by an object with the features of claim 1. The clamping and/or gripping device comprises a base housing with a central longitudinal axis. For clamping and/or gripping, the component and/or the component carrier is preferably fed along the central longitudinal axis to the clamping and/or gripping device. The clamping and/or gripping device further comprises a clamping element, in particular a clamping jaw and/or gripping jaw, which is mounted in the base housing so as to be displaceable radially to the central longitudinal axis. The clamping and/or gripping device also has a fluid drive for driving the at least one clamping element. The fluid drive of the clamping and/or gripping device is arranged in or on the base housing and/or is integrated in the base housing.

The advantages of a fluid drive integrated in the base housing are that no complex wiring is required between the system and the clamping and/or gripping device. In addition, there is a high level of efficiency, as there is no leakage loss at the transition between the system and the clamping and/or gripping device, which means that low operating costs can be achieved. Furthermore, the proximity between the fluid drive and the at least one clamping element allows for more reliable and more precise information about the clamping situation. Since the fluid drive does not have to be arranged in the force flow, there is a high degree of flexibility in the design and integration of the fluid drive into the clamping and/or gripping device. Furthermore, the reaction force of the clamping force does not have to be absorbed by the fluid drive, so that small bearings can be used for the fluid drive. A fluid drive arranged in or on the base housing provides an advantageous combination of a drive integrated in the clamping and/or gripping device and a drive arranged outside the force flow.

The clamping element is preferably designed separately from the base housing. The base housing preferably has a guide in which the clamping element is guided in a translational manner.

An advantageous embodiment of the invention provides that the fluid drive comprises an electric motor arranged in the base housing and/or a hydraulic pump arranged in the base housing. The hydraulic pump is preferably reversible and/or designed as a miniature hydraulic pump and/or as a gear pump. The integration of the motor and/or the hydraulic pump provides a self-contained assembly that can be easily integrated into existing machining centers or systems. Gear pumps enable a uniform fluid flow, high pressures and easy maintenance. In addition, gear pumps are self-priming, i.e. they can lift fluids and pump them against a pressure, have a compact design so that the clamping and/or gripping device is particularly flat, and can also pump viscous fluids.

It is advantageous if the fluid drive is designed in such a way that a change in the direction of rotation of the motor causes a change in the direction of displacement of the at least one clamping element. The direction of displacement of the at least one clamping element extends perpendicular to the central longitudinal axis, wherein the at least one clamping element can be displaced towards the central longitudinal axis into an inner position and away from the central longitudinal axis into an outer position. When gripping and/or clamping inside, the clamping element is in the closed position in the inner position and in the open position in the outer position. When gripping and/or clamping outside, the clamping element is in the closed position in the outer position and in the open position in the inner position. Such a design enables the opening (clamping element in the open position) and closing (clamping element in the closed position) of the clamping and/or gripping device and limiting the maximum pressure without the use of expensive and large valve technology, in particular solenoid-controlled directional valves. For solenoid-controlled directional valves, an additional electrical cable is required for control, which can be omitted here. To switch between opening and closing the delivery direction of the hydraulic pump and/or gear pump, in particular the reversing pump, must be reversed by reversing the direction of rotation of the motor.

It is also advantageous if the clamping and/or gripping device has a pressure cylinder arranged in the base housing, the pressure cylinder extending along a cylinder axis running perpendicular to the central longitudinal axis. The fluid drive also preferably has a pressure piston arranged in the pressure cylinder and mounted so as to be displaceable along the cylinder axis. The pressure piston is preferably displaceable parallel to the clamping elements. The pressure cylinder and the pressure piston preferably delimit a first pressure chamber to which a fluid pressure can be applied and a second pressure chamber to which a fluid pressure can be applied. In relation to the central longitudinal axis, the first pressure chamber is preferably arranged radially on the outside and the second pressure chamber is arranged radially on the inside. During internal clamping and/or internal gripping, the first pressure chamber can be subjected to a fluid pressure in order to move the at least one clamping element into the closed position, and the second pressure chamber can be subjected to a fluid pressure in order to move the at least one clamping element into the open position. During external clamping and/or external gripping, it is the other way round. Such a fluid drive, in particular a cylinder-piston unit, has the advantages of providing a high clamping and gripping force, high positioning accuracy, a simple construction and high resistance to harsh environmental conditions. Preferably, one pressure cylinder is provided for each clamping element or for each two clamping elements. Preferably, one pressure piston is provided for each clamping element.

Preferably, the fluid drive has a volume balance between the open position and the closed position or between the first pressure chamber and the second pressure chamber, so that the same fluid volume has to be provided for opening and closing the clamping elements in the first pressure chamber or in the second pressure chamber. Accordingly, a compensation tank for balancing the volumes of the first pressure chamber and the second pressure chamber can be dispensed with.

It is also advantageous that the level of clamping force can be variably adjusted to the clamping device by selecting the piston cross-section of the pressure piston and/or that the jaw stroke of the clamping elements can be variably adjusted by selecting the hydraulic piston stroke of the pressure piston.

Preferably, a fluid tank is provided in or on the base housing, which serves as a reservoir for the fluid of the fluid drive. An integrated fluid tank supports the integration of the fluid drive in the clamping or gripping device. Alternatively or additionally, the fluid drive has a fluid line system closed in the base housing. External line connections are therefore not required.

An advantageous development of the invention provides that the at least one pressure piston is coupled directly to the at least one clamping element. A high volume balance between the first pressure chamber and the second pressure chamber can also preferably be achieved by means of a piston rod-less fluid drive. This is preferably possible by means of the direct coupling between the pressure piston and the clamping element. The piston movement along the cylinder axis and the movement of the clamping elements parallel to the cylinder axis are synchronous and/or parallel to the piston movement. The volume between the opening and closing chambers are identical and therefore do not have to be balanced with each other via an equalizing container. Alternatively or additionally, the at least one pressure piston is coupled to at least one clamping element by means of a synchronization, in particular a synchronization means, preferably a pinion-rack mechanism and/or connecting rod synchronization, preferably a synchronization pinion. Alternatively, the synchronization can be achieved by means of a connecting rod. For this purpose, the at least one pressure piston has a rack profile which is in engagement with the synchronization pinion during operation. When using multiple pressure pistons and/or multiple clamping elements, the movement of the pressure pistons or clamping elements can be synchronized using the synchronization pinion. Furthermore, rack profiles can also be provided on the clamping elements, which engage with the synchronization pinion during operation.

It is advantageous if the clamping and/or gripping device has a, in particular purely, electrical or electronic system interface in the low voltage range with a maximum input power of 100 W. The permissible voltage of the system interface is preferably in a range between 0-48 V DC, preferably 24 V DC. The permissible current is preferably in a range between 0-10 A, in particular 4 A. Due to the low input power and/or only one electrical supply, a particularly simple energy supply is possible, in particular by means of a contactless interface, preferably by means of induction.

It is also advantageous if the clamping and/or gripping device has a control unit arranged in or on the base housing for controlling and/or regulating the fluid drive and/or the at least one clamping element. The control unit can also be additionally or alternatively set up for communication with a higher-level control system and/or a system control system.

It is also advantageous if the clamping and/or gripping device is designed to collect and process the information of the clamping or gripping situation and to take it into account when controlling and regulating the clamping and/or gripping device. The clamping and/or gripping device is preferably designed to regulate the fluid drive, in particular the motor, and/or its torque, speed, direction of rotation. The clamping and/or gripping device is preferably designed to detect the fluid pressure in the clamping and/or gripping device. The clamping and/or gripping device is preferably designed to detect the vibration during processing in the clamping and/or gripping device, in particular near or at the clamping or gripping point.

The clamping and/or gripping device preferably has a power booster or power amplifier arranged in or on the base housing for the short-term provision of a higher power to the fluid drive. The power booster can therefore provide additional power in addition to the power provided by the system interface. For example, the high clamping pressure can be built up in this way. The power booster can preferably be designed as a capacitive or electromechanical dispenser. The power booster can also have a voltage transformer, which in particular transforms the voltage provided to the motor of the fluid drive and/or provides a higher voltage for the motor in the short term.

An advantageous development of the invention provides that the clamping and/or gripping device has a sensor device arranged in or on the base housing with at least one pressure sensor for detecting the fluid pressure in the clamping and/or gripping device and/or with at least one vibration sensor for detecting the shrinkage during processing of the clamping and/or gripping device and/or a position sensor arranged in or on the base housing. The sensor device preferably generates signals which are transmitted to the control unit. The control unit is preferably set up in such a way that it controls the fluid drive and/or the clamping elements depending on the signals from the sensor device.

A further advantageous development of the invention provides that the clamping and/or gripping device has a pressure amplifier arranged in or on the base housing for increasing the fluid pressure. The pressure amplifier preferably has a differential piston. A differential piston has two working surfaces of different sizes. The larger working surface of the differential piston is used to absorb a lower input pressure and to transfer the resulting force to the smaller working surface of the pressure piston, which leads to a higher output pressure. It is advantageous if the differential piston is part of the pressure piston.

It is advantageous if the fluid drive can be operated in a rapid motion and in a power motion. The hydraulic pump preferably provides a lower first fluid pressure, in particular in a range between 30 bar and 60 bar, at a maximum fluid flow rate. The hydraulic pump can be set up to only move the pressure pistons and/or the clamping elements without force. to be used. The pressure amplifier, in particular the differential piston, is preferably connected downstream of the hydraulic pump, which provides a higher second fluid pressure, in particular in a range between 180 bar and 250 bar, with a lower fluid flow rate. The combination of the hydraulic pump with the pressure amplifier thus serves for the rapid movement and powerful closing of the pressure pistons and/or the clamping elements. Accordingly, a fluid drive, in particular a hydraulic pump, with a low power consumption, in particular of less than 100 W, can be used. The fluid pressure is negatively proportional to the fluid flow rate, with the fluid pressure determining the clamping or gripping force of the clamping elements and/or the fluid flow rate determining the travel speed of the clamping elements and/or the pressure pistons. Accordingly, only the hydraulic pump can be used for rapid traverse and the hydraulic pump and the pressure amplifier in combination can be used for power traverse. The fluid drive is preferably designed in such a way that the pressure amplifier is only switched on when the fluid pressure is in a range of 30 bar to 60 bar. To switch on the pressure amplifier, a pressure-controlled, passive valve, in particular a pressure sequence valve or pressure switching valve or connection valve and/or check valve, is preferably provided. Alternatively, the valve can also be actively controlled, e.g. by means of electricity.

Alternatively, it is conceivable that in TANDEM clamping the clamping and/or gripping device can be operated at 60 bar in rapid and power mode without a pressure amplifier.

The object underlying the invention is also achieved by a clamping device of claim 12. The clamping device serves to clamp a clamping element of a clamping and/or gripping device, in particular a previously described clamping and/or gripping device. The clamping and/or gripping device has a pressure cylinder extending along a cylinder axis, in which a clamping ring and a pressure piston with a piston section that is displaceably mounted along the cylinder axis are arranged. The clamping ring is not movable relative to the pressure cylinder and has a ring slope that runs obliquely relative to the cylinder axis. The clamping device comprises a first clamping element that is movable along the cylinder axis relative to the piston section and/or the clamping ring and has a first clamping slope, wherein in particular the first clamping slope runs obliquely to the cylinder axis. The clamping device further comprises a second clamping element that is movable along the cylinder axis relative to the piston section and/or the clamping ring and/or the first clamping element and has a second clamping slope and a third clamping slope. The second clamping slope and/or the third clamping slope preferably run obliquely to the cylinder axis. In addition, the clamping device comprises a clamping element arranged along the cylinder axis relative to the piston section and/or the clamping ring and/or the first clamping element and/or the second clamping element movable clamping slide. In a clamped state, the at least one clamping element of the clamping and/or gripping device can be fixed by means of the clamping device, in particular by means of the first clamping element and/or the second clamping element and/or the clamping ring. The clamping device can be used to ensure that the clamping elements are fixed in position and/or that their gripping force is maintained.

It is advantageous if the clamping device is designed in such a way that, in the clamped state, the first clamping element can be acted upon and/or displaced towards the central longitudinal axis by means of a fluidic pressure in a first pressure chamber and/or the second clamping element can be acted upon and/or displaced away from the central longitudinal axis by means of the clamping slide. The clamping slide is preferably urged away from the central longitudinal axis by a spring means and/or the gripped component and/or component carrier. Due to the bidirectional mode of action of the clamping device, the clamping effect of the clamping device increases with increasing load on the clamping elements, so that the position maintenance and/or the gripping force maintenance also increases with increasing load until the components of the clamping device are destroyed. The clamping device is preferably designed in such a way that a fluid pressure can be applied to a second pressure chamber to release the clamped state of the clamping device. The first clamping element can thus be displaced away from the central longitudinal axis and the clamping is released.

It is also advantageous if the first clamping element is trapezoidal and/or the first clamping bevel is provided on an outer circumference of the first clamping element. It is also advantageous if the second clamping element is hollow and/or the second clamping bevel is provided on an inner circumference of the second clamping element and the third clamping bevel is provided on an outer circumference of the second clamping element. It is also advantageous if the clamping ring is hollow and/or the ring bevel is provided on an inner circumference of the clamping ring. It is also advantageous if, when the clamping device is in a clamping state, the first clamping bevel comes into contact with the second clamping bevel and the third clamping bevel comes into contact with the ring bevel. A particularly high clamping effect can be achieved due to the two clamping points acting simultaneously in the clamping state.

It is also advantageous if the clamping device is designed to be spring-loaded. Preferably, the clamping slide is pre-tensioned away from the and/or the piston section towards and/or the first clamping element towards the central longitudinal axis by means of at least one spring means. Accordingly, a clamping or gripping force on the clamping element can be applied without operating the fluid drive. Furthermore, vibration during operation can be compensated by means of the spring means.

An advantageous development provides that a previously described clamping and/or gripping device has a previously described clamping device. Accordingly, the disadvantage in hydraulic applications that when the fluid pressure drops, the clamping force is also reduced linearly can be compensated for, since most clamping elements are not mechanically self-locking. Due to the integrated design of the fluid drive, no external power connections are possible in this regard. In this case, it is necessary to operate the fluid drive continuously, which is disadvantageous due to the energy consumption and heat development in the clamping and/or gripping device. Due to the clamping device, a self-locking form fit is provided, in which the position and the clamping or gripping force are maintained even when the fluid pressure is removed. It is advantageous if the clamping device is arranged in or on the base housing, in particular if it is integrated in the base housing.

The control unit is preferably designed to control and/or regulate the position and/or the reaction force of the at least one clamping element. It is also advantageous if the clamping device is part of the pressure piston. It is also advantageous if the control unit is designed such that the power booster, in particular the capacity and/or the battery, are charged in the clamped state. In the clamped state, the fluid drive, in particular the motor, can additionally or alternatively be switched off.

It is also advantageous if the clamping and/or gripping device has a plurality of clamping elements, wherein the plurality of clamping elements are mounted so as to be displaceable along a clamping plane. The volume center of the clamping elements is preferably located in the clamping plane. It is also advantageous if the fluid drive, in particular the motor and/or the hydraulic pump and/or the fluid tank and/or the control unit and/or the sensor device and/or the pressure amplifier and/or the power booster, is located in the clamping plane and/or intersects the clamping plane.

The clamping and/or gripping device preferably has two, three, four or six clamping elements, which are arranged in a cross or star shape. It is advantageous if the motor and/or the hydraulic pump and/or the fluid tank and/or the control unit and/or the sensor device and/or the pressure amplifier and/or the power booster are arranged in or on the base housing between two clamping elements.

The description further relates to a previously described clamping and/or gripping device with a power booster arranged in or on the base housing.

The description further relates to a previously described clamping and/or gripping device with a pressure amplifier arranged in or on the base housing.

The description further relates to a previously described clamping and/or gripping device with a clamping device arranged in or on the base housing.

The object underlying the invention is also achieved by a pressure piston with the features of claim 17. A pressure bolt for a clamping and/or gripping device, in particular as described above, with a piston section integrated in the pressure piston and either with a clamping device integrated in the pressure piston, in particular as described above, and/or with a pressure amplifier integrated in the pressure piston, in particular a differential piston.

Further details and advantageous embodiments of the invention can be found in the following description, on the basis of which embodiments of the invention are further described and explained.

Fig. 1

eine perspektivische Ansicht einer Spann- und/oder Greifvorrichtung;

Fig. 2

eine Oberansicht der Spann- und/oder Greifvorrichtung gemäß Fig. 1;

Fig. 3

eine Seitenansicht der Spann- und/oder Greifvorrichtung gemäß Fig. 1;

Fig. 4

eine Seitenansicht der Spann- und/oder Greifvorrichtung gemäß Fig. 1 mit einer Spannpalette;

Fig. 5

eine Schnittansicht einer Hydraulikpumpe der Spann- und/oder Greifvorrichtung gemäß Fig. 1;

Fig. 6

eine Vorderansicht einer Steuereinheit der Spann- und/oder Greifvorrichtung gemäß Fig. 1;

Fig. 7

eine Detailansicht im Schnitt der Steuereinheit und der Sensorvorrichtung der Spann- und/oder Greifvorrichtung gemäß Fig. 1;

Fig. 8

eine Oberansicht der Spann- und/oder Greifvorrichtung gemäß Fig. 1 in einer Öffnungsstellung und in einem Lösezustand;

Fig. 9

eine Schnittansicht der Spann- und/oder Greifvorrichtung gemäß Fig. 8;

Fig. 10

eine Oberansicht der Spann- und/oder Greifvorrichtung gemäß Fig. 1 in einer Schließstellung und in einem Lösezustand;

Fig. 11

eine Schnittansicht der Spann- und/oder Greifvorrichtung gemäß Fig. 10;

Fig. 12

eine Oberansicht der Spann- und/oder Greifvorrichtung gemäß Fig. 1 in einer Schließstellung und in einem Klemmzustand; und

Fig. 13

eine Schnittansicht der Spann- und/oder Greifvorrichtung gemäß Fig. 13.

They show:

Fig. 1

a perspective view of a clamping and/or gripping device;

Fig. 2

a top view of the clamping and/or gripping device according to Fig. 1 ;

Fig. 3

a side view of the clamping and/or gripping device according to Fig. 1 ;

Fig. 4

a side view of the clamping and/or gripping device according to Fig. 1 with a clamping pallet;

Fig. 5

a sectional view of a hydraulic pump of the clamping and/or gripping device according to Fig. 1 ;

Fig. 6

a front view of a control unit of the clamping and/or gripping device according to Fig. 1 ;

Fig. 7

a detailed view in section of the control unit and the sensor device of the clamping and/or gripping device according to Fig. 1 ;

Fig. 8

a top view of the clamping and/or gripping device according to Fig. 1 in an open position and in a release state;

Fig. 9

a sectional view of the clamping and/or gripping device according to Fig. 8 ;

Fig. 10

a top view of the clamping and/or gripping device according to Fig. 1 in a closed position and in a released state;

Fig. 11

a sectional view of the clamping and/or gripping device according to Fig. 10 ;

Fig. 12

a top view of the clamping and/or gripping device according to Fig. 1 in a closed position and in a clamped state; and

Fig. 13

a sectional view of the clamping and/or gripping device according to Fig. 13 .

In the Fig. 1 to 4 a clamping and/or gripping device 10 for clamping or gripping a component or component carrier (not shown) is shown with a base housing 12 and with a central longitudinal axis 14. In the base housing 12, four clamping elements 16 are arranged which are mounted so as to be displaceable radially to the central longitudinal axis 14 and are preferably guided in a guide 13 so as to be movable in translation. The clamping and/or gripping device 10 can be designed as a clamping means, gripping means, chuck or zero-point clamping module.

According to Fig. 4 the clamping and/or gripping device 10 can be arranged on a machine table 20 of a machining center 22 or a machining system by means of a clamping pallet 18. For this purpose, the clamping pallet 18 has clamping bolts 24 which can be received in bolt receptacles (not shown) of the machine table 20, in particular in at least one zero-point clamping module (not shown).

The clamping and/or gripping device 10 has according to Fig. 2 a fluid drive 26 integrated in the base housing. The fluid drive 26 has an electric motor 28 and a hydraulic pump 30. The clamping elements 16 can be driven by means of the fluid drive 26.

According to Fig. 5 the hydraulic pump 30 can be designed as a gear pump 32. The gear pump 32 has a pump housing 34, a first pump gear 36 arranged in the pump housing 34 and a second pump gear 38 arranged in the pump housing 34. The first pump gear 36 can be driven by means of the motor 28. The first pump gear 36 meshes with the second Pump gear 38 so that it is moved along. The first pump gear 36 has the same direction of rotation as the output shaft of the motor 28 (not shown). The second pump gear 38 has an opposite direction of rotation to the direction of rotation of the output shaft of the motor 28 (not shown) and the first pump gear 36. Alternatively, it is conceivable that a single-stage gear, in particular a spur gear, is arranged between the first pump gear 36 and the motor 28. In this case, the first pump gear 36 rotates against the direction of rotation of the motor 28. The first pump gear 36 and the second pump gear 38 are rotatably mounted by means of a gear shaft bearing in the pump housing 34 about a drive axis 42 running parallel to the output shaft of the motor 28. The first pump gear 36 and the second pump gear 38 are preferably mounted on both sides in bearing glasses. In the assembled state, the drive axis 42 preferably runs parallel or perpendicular to the central longitudinal axis 14. The first pump gear 36 and the second pump gear 38 transport the fluid between the teeth of the pump gears 36, 38 and the pump housing 34.

Furthermore, the gear pump 32 according to Fig. 5 a first connecting channel 44 and a second connecting channel 46, wherein, depending on the direction of rotation of the motor 28, fluid is conveyed from the first connecting channel 44 to the second connecting channel 46 and vice versa. A hydraulic oil is preferably used as the fluid.

To provide the fluid, the clamping and/or gripping device 10 according to Fig. 2 a fluid tank 48 integrated in the base housing. The fluid tank 48 is preferably fluidically connected to the first connecting channel 44 and/or the second connecting channel 46.

To move the clamping elements 16 perpendicular to the central longitudinal axis, Fig. 9 , 11 and 13 A cylinder-piston unit is provided for each clamping element 16. A pressure cylinder 52 extending along a cylinder axis 50 is provided in the base housing 12, the cylinder axis 50 preferably running perpendicular to the central longitudinal axis 14. A pressure piston 54 is mounted in the pressure cylinder 52 so as to be displaceable along the cylinder axis 50. The pressure piston 54 has a piston section 56, the piston section 56 and the pressure cylinder 52 each defining a first pressure chamber 58 to which fluid pressure can be applied and a second pressure chamber 60 to which fluid pressure can be applied. The first pressure chamber 58 is preferably arranged radially outward relative to the central longitudinal axis 14 and the second pressure chamber 60 is arranged radially inward relative to the central longitudinal axis 14.

During internal clamping or internal gripping, the first pressure chamber 58 can be subjected to a fluid pressure so that the clamping element 16 is pushed and displaced into the closed position, and the second pressure chamber 60 can be subjected to a fluid pressure so that the clamping element 16 is moved into the open position is pushed and displaced. Preferably, the first connecting channel 44 is fluidically connected to the first pressure chamber 58. Preferably, the second connecting channel 46 is fluidically connected to the second pressure chamber 60. Accordingly, depending on the direction of rotation of the motor 28, a fluid can be conveyed from the hydraulic pump 30 into the first pressure chamber 58 or the second pressure chamber 60. Preferably, the connecting channels 44, 46 and the pressure chambers 58, 60 form a closed fluid line system 61.

To move the clamping elements 16, the pressure pistons 54, in particular the piston section 56, are Fig. 9 , 11 and 13 by means of a coupling section 62 each with the clamping element 16. Accordingly, the movement of the pressure piston 54, in particular the piston section 56, is synchronized with the clamping element 16. Due to the direct coupling between the piston section 56 and the clamping element 16, a piston rod can be dispensed with, since the pressure pistons 54 are also guided by means of the guide of the clamping elements 16.

On the central longitudinal axis 14, in particular in the center of the clamping and/or gripping device 10, according to Fig. 8 , 10 and 12 in synchronization pinion 64 is provided, which cooperates with at least two pressure pistons 54. For this purpose, the pressure pistons 54 have a rack profile 68 on a free piston end 66 facing the central longitudinal axis 14, which is in engagement with the synchronization pinion 64 during operation. Consequently, the movement of the pressure pistons 54 and clamping elements 16 in engagement with the synchronization pinion 64 is synchronized with one another.

Furthermore, the clamping and/or gripping device 10 according to Fig. 2 , 6 and 7 a control unit 70 arranged in the base housing for controlling and regulating the clamping and/or gripping device 10, in particular the fluid drive 26. The control unit 70 preferably has according to Fig. 6 a logic and/or communication module 70A and/or a pump control module 70B and/or a sensor module 70C and/or a power supply and/or communication module 70D and/or a capacitive energy storage module 70E and/or a pump connection unit 70F and/or a pressure sensor connection unit 70G.

Furthermore, the clamping and/or gripping device 10 has a sensor device 72 arranged in the base housing 12, which according to Fig. 2 and 7 a pressure sensor 74 for detecting the fluid pressure in the fluid line system 61, in particular in the pressure chambers 58, 60 and/or in the hydraulic pump 30, and/or a vibration sensor 76 for detecting the shrinkage during the processing of the clamping and/or gripping device 10 and/or a motor sensor for detecting the motor current of the motor 28. The sensor device 72 is preferably linked to the sensor module 70C. The control unit 70 is set up in such a way that it controls the clamping and/or gripping device 10 depending on the signals from the sensor device 72. The control unit 70 is preferably set up to control and regulate the fluid drive 26, in particular the motor 28, with regard to the torque, the speed setting and/or the direction of rotation. The control unit 70 is preferably set up in such a way that the fluid pressure provided in the clamping and/or gripping device 10 is determined depending on a measurement of the actual pressure at the pressure sensor and/or the motor current, so that no pressure relief valve is required to switch off the fluid drive 26 when the fluid pressure to be set is reached. The compact design of the clamping and/or gripping device 10 and the control unit 70 integrated in the base housing 12 are advantageous here.

The clamping and/or gripping device 10 preferably has a purely electrical or electronic system interface in the low voltage range with a maximum input power of 100 W. The permissible voltage of the system interface 78 is preferably in a range between 0-48 V DC, preferably 24 V DC. The permissible current is preferably in a range between 0-10 A, in particular 4 A. Due to the low input power and/or only one electrical supply, a particularly simple media supply, in particular contactless and/or by means of induction, is possible between the machining center 22 and the clamping and/or gripping device 10. The system interface 78 is preferably linked to the logic and/or communication module 70A and/or to the power supply and/or communication module 70D.

In addition, the clamping and/or gripping device 10 according to Fig. 6 a power booster 80 or power amplifier for the short-term provision of a higher power at the fluid drive 26. The power booster 80 can therefore provide additional power in addition to the power provided by the system interface. For example, when starting up the clamping elements 16, the static friction can be overcome. The power booster 80 can preferably be designed as a capacitive or electrochemical storage device. The power booster 80 can also be integrated in the energy storage module 70E. Furthermore, the power booster 80 can have a voltage transformer 82, which in particular transforms the voltage provided for the motor 28 of the fluid drive 26, so that a constant voltage and/or a short-term higher voltage can be provided for the motor 28. The voltage transformer 82 can preferably be integrated in the voltage supply and/or communication module 70D.

The clamping and/or gripping device 10 also has the pressure amplifier 71 shown for increasing the fluid pressure, which is designed in particular as a differential piston. A differential piston has two working surfaces of different sizes. The larger working surface of the differential piston is used to absorb a lower input pressure and the resulting reaction force to the smaller working surface of the pressure piston, which leads to a higher output pressure. It is advantageous if the differential piston is part of the pressure piston 54.

To compensate for the disadvantage in hydraulic applications that when the fluid pressure drops, the clamping force also drops linearly, since most clamping elements 16 are not mechanically self-locking, the clamping and/or gripping device 10 according to the Fig. 9 , 11 and 13 a clamping device 100. Due to the clamping device 100, a self-locking form fit is provided, in which the position and the clamping or gripping force are maintained even when the fluid pressure on the clamping elements 16 is removed. It is advantageous if the clamping device 100 is arranged in or on the base housing 12, in particular integrated in the base housing 12.

The clamping device 100 serves to clamp the clamping elements 16 and can be operated in a clamping state and a release state. The Fig. 8 and 9 show the clamping and/or gripping device 10 in the open position and in the release state. The Fig. 10 and 11 show the clamping and/or gripping device 10 in the closed position and in the released state. The Fig. 12 and 13 show the clamping and/or gripping device 10 in the closed position and in the clamping state.

The clamping device 100 is preferably integrated in the pressure piston 54. The clamping device 100 has according to the Fig. 9 , 11 and 13 a clamping ring 102 with a ring bevel 104, a first clamping element 106 with a first clamping bevel 108, a second clamping element 110 with a second clamping bevel 112 and a third clamping bevel 114 and a clamping slide 116 with a push section 118.

The clamping ring 102 is arranged immovably in the pressure cylinder 52, in particular clamped, and/or hollow. The clamping ring 102 can alternatively be formed in one piece with the base housing 12. The ring bevel 104 is arranged at an angle, in particular at an angle of 25°, to the cylinder axis 50. The first clamping element 106 has a conical foot section 120, which tapers in particular towards the central longitudinal axis 14, and a cylindrical head section 122. The first clamping bevel 108 is arranged on an outer circumference of the first clamping element 106, in particular on the foot section 120. The first clamping bevel 108 is arranged at an angle, in particular self-locking, preferably at an angle of less than 15°, in particular 10°, to the cylinder axis 50. The second clamping element 110 is cylindrical or hollow and/or ring-shaped. The second clamping bevel 112 is arranged on an inner circumference of the second clamping element 110 and/or the third clamping bevel 114 is arranged on an outer circumference of the second clamping element 110, wherein the inner circumference tapers towards the central longitudinal axis 14 and/or the outer circumference tapers away from the central longitudinal axis 14. The second clamping bevel 112 and/or the third clamping bevel 114 is inclined, in particular at an angle of 25°, to the cylinder axis 50. The clamping slide 116 is also hollow and has Fig. 11 on its inner circumference a guide portion 124 in which the first clamping element 106, in particular the head portion 122, is guided.

The pressure piston 54 is displaceable relative to the pressure cylinder 52 and the clamping ring 102 along the cylinder axis 50. The first clamping element 106 is displaceable relative to the clamping ring 102 and the piston section 56 along the cylinder axis 50. The second clamping element 106 is displaceable relative to the clamping ring 102, the piston section 56 and the first clamping element 106. The clamping slide 116 is displaceable relative to the clamping ring 102, the piston section 56 and the first clamping element 106.

Between the piston section 56 and the clamping slide 116 is according to Fig. 9 , 11 and 13 a first spring means 126 is provided which preloads the piston section 56 towards the central longitudinal axis 14 and/or which preloads the clamping slide 116 away from the central longitudinal axis 14. This allows preloading to be provided on the clamping elements 16 which maintains the gripping force. Furthermore, this allows the clamping of the clamping elements 106, 110 and the clamping ring 102 to be strengthened.

The driving and displacement of the clamping elements 16 is carried out as follows: In the initial state, the clamping elements 16 are in accordance with Fig. 8 and 9 in the open position and in the release state, taking into account external clamping or external gripping. With internal gripping or internal clamping, the orientation is reversed. The pressure piston 54 and the clamping device 100, in particular the first clamping element 106 and/or the second clamping element 110 and/or the clamping slide 116, are arranged radially outward relative to the central longitudinal axis 16. To move the clamping elements 16 into the closed position, a fluid pressure is applied to the first pressure chambers 58 by means of the fluid drive 26. Fig. 10 and 11 shows the clamping and/or gripping device 10 in this closed position. The clamping device 100, in particular the first clamping element 106 and/or the second clamping element 110 and/or the clamping slide 116, do not move relative to the piston section 56 and/or relative to one another. As soon as a component or a component carrier is clamped or gripped on the clamping elements 16, the reaction force increases. Due to the small dimensions of the fluid drive 26, the pressure amplifier is now switched on so that a higher clamping or gripping force can be provided on the clamping elements 16. To maintain the position and/or clamping or gripping force, the fluid drive 26 and the pressure amplifier can be operated continuously.

It is conceivable that, depending on the orientation of the clamping, the orientation of the clamping device 100 is also changed.

Alternatively, the clamping device 100 can be in the clamping state according to Fig. 12 and 13 be moved. In the clamped state, the clamping device 100 receives the position and/or clamping or gripping force of the clamping elements 16. For this purpose, the clamping element 16 comes into contact with the component to be clamped or gripped. Consequently, a reaction force is transmitted to the pressure piston 56 by means of the coupling section 62. Furthermore, the first pressure chamber 58 is subjected to a fluid pressure. On the one hand, the clamping slide 116 is pushed radially outwards with respect to the central longitudinal axis 14 by means of the first spring means 126 and, on the other hand, the first clamping element 106 is pushed radially inwards with respect to the central longitudinal axis 14. When the first clamping element 106 moves radially inward relative to the central longitudinal axis 14, the first clamping bevel 108 slides over the second clamping bevel 112. Due to the opposite orientation of the first clamping bevel 108 and the second clamping bevel 112, the second clamping element 110 is pushed radially outward relative to the cylinder axis 50. The third clamping bevel 114 slides over the annular bevel 104. However, the freedom of movement of the second clamping element 110 radially inward toward the central longitudinal axis 14 is limited by the clamping slide 116. Consequently, in the gripped or tensioned state, the second clamping element 110 is pushed radially inward relative to the central longitudinal axis 14 and radially outward relative to the cylinder axis 50. Accordingly, in the clamped state, the first clamping bevel 108 and the second clamping bevel 112 as well as the third clamping bevel 114 and the ring bevel 104 lie against one another, with their contact surfaces in particular intersecting a clamping plane 128 running perpendicular to the cylinder axis 50. With increasing gripping or clamping force and increasing reaction force, the clamping device 100 is clamped more tightly due to the first pressure chamber 58 and the clamping slide 116.

To release the clamping state, the second pressure chamber 60 must be subjected to a fluid pressure. For this purpose, the pressure piston 54 has a through hole 130 running parallel to the central longitudinal axis 14, which fluidically connects the second pressure chamber 60 to the inner circumference of the clamping slide 116 and/or to the first clamping element 106, in particular the head section 122. The head section 122 preferably has a head seal 132, which fluidically separates the first pressure chamber 58 and the second pressure chamber 60 from one another. Furthermore, the first clamping element 106 is prestressed towards the central longitudinal axis 14 by means of a second spring means 134, wherein the second spring means 134 is arranged in the clamping slide 116, in particular on its inner circumference. When the second pressure chamber 60 is subjected to a fluid pressure which is greater than the fluid pressure in the first pressure chamber 58 and the pressure resulting from the second spring means 134, the first clamping element 106 is displaced radially outward away from the central longitudinal axis 14. In the process, the clamping between the first clamping element 106, the second clamping element 110 and the clamping ring 102 is released. After the clamping is released, the pressure piston 54 and the clamping element 16 are moved in relation to the central longitudinal axis 14 radially outward, so that the clamping and/or gripping device 10 is again in the initial state, i.e. in the open position and in the release state, according to Fig. 8 and 9 is located.

Claims (17)

Clamping and/or gripping device (10) comprising: - a base housing (12) with a central longitudinal axis (14), - at least one clamping element (16) guided in the base housing (12) so as to be displaceable radially to the central longitudinal axis (14), - a fluid drive (26) for driving the at least one clamping element (16), wherein the fluid drive (26) is arranged in or on the base housing (12). Clamping and/or gripping device (10) according to claim 1, wherein the fluid drive (26) comprises an electric motor (28) arranged in or on the base housing (12) and/or a hydraulic pump (30) arranged in or on the base housing (12). Clamping and/or gripping device (10) according to claim 2, wherein a change in a direction of rotation of the motor (28) causes a change in a direction of displacement towards or away from the central longitudinal axis (14) of the at least one clamping element (16). Clamping and/or gripping device (10) according to one of the preceding claims, wherein the base housing (12) has at least one pressure cylinder (52) extending along a cylinder axis (50) running perpendicular to the central longitudinal axis (14), wherein the fluid drive (26) has a pressure piston (54) arranged in or on the pressure cylinder (52) and displaceably mounted along the cylinder axis (50), and
wherein in particular the pressure cylinder (52) and the pressure piston (54) each delimit a pressurizable first pressure chamber (58) for displacing the clamping element (16) from an open position into a closed position and a pressurizable second pressure chamber (60) for displacing the clamping element (16) from the closed position into the open position. Clamping and/or gripping device (10) according to one of the preceding claims, wherein it has a fluid tank (48) arranged in or on the base housing (12), and/or wherein the fluid drive (26) has a fluid line system (61) closed in the base housing (12). Clamping and/or gripping device (10) according to one of the preceding claims, wherein the pressure piston (54) is coupled to the at least one clamping element (16) directly and/or by means of a synchronization means (64). Clamping and/or gripping device (10) according to one of the preceding claims, wherein it has an electrical system interface in the low-voltage range with a maximum input power of 100 W. Clamping and/or gripping device (10) according to one of the preceding claims, wherein it comprises a control unit (70) for controlling and/or regulating the fluid drive (26) and/or the at least one clamping element (16). Clamping and/or gripping device (10) according to one of the preceding claims, wherein it has a power booster (80) for the short-term provision of a higher power at the fluid drive (26). Clamping and/or gripping device (10) according to one of the preceding claims, wherein it comprises a sensor device (72) with at least one pressure sensor (74) for detecting the fluidic pressure in the clamping and/or gripping device (10) and/or with at least one vibration sensor (76) for detecting the shrinkages during operation of the clamping and/or gripping device (10) and/or with at least one position sensor. Clamping and/or gripping device (10) according to one of the preceding claims, wherein it comprises a pressure amplifier (71) for increasing the fluidic pressure, in particular a differential piston. Clamping device (100) for clamping a clamping element (16) of a clamping and/or gripping device (10), in particular according to one of the preceding claims, wherein the clamping and/or gripping device (10) has a pressure cylinder (52) extending along a cylinder axis (50) with a fixed clamping ring (102) comprising a ring bevel (104) and a pressure piston (54) with a piston portion (56), and wherein the clamping device (100) comprises: - a first clamping element (106) movable relative to the piston section (54) with a first clamping slope (108), - a second clamping element (110) movable relative to the piston portion (54) and the first clamping element (106) with a second clamping bevel (112) and a third clamping bevel (114), and - a clamping slide (116) movable relative to the piston portion (54), the first clamping element (106) and the second clamping element (110), wherein in a clamping state the clamping element (16) can be fixed by means of the clamping device (100). Clamping device (100) according to claim 12, wherein it is designed such that in the clamping state the first clamping element (106) can be acted upon and/or displaced towards the central longitudinal axis (14) by means of a fluid pressure in the first pressure chamber (58) and/or the second clamping element (110) can be acted upon and/or displaced away from the central longitudinal axis (14) by means of the clamping slide (116). Clamping device (100) according to claim 12 or 13, wherein the first clamping element (106) is wedge-shaped and the first clamping bevel (108) is provided on an outer circumference, wherein the second clamping element (110) is hollow and the second clamping bevel (112) and the third clamping bevel (114) are provided on an inner circumference, wherein the clamping ring (102) is hollow and the annular bevel (104) is provided on an inner circumference, and/or wherein the clamping device (100) is designed such that in a clamping state the first clamping bevel (108) cooperates with the second clamping bevel (112) and the third clamping bevel (114) cooperates with the annular bevel (104). Clamping device (100) according to one of claims 12 to 14, wherein by means of at least one first spring means (126) the clamping slide (116) is prestressed away from and/or by means of at least one second spring means (134) the piston portion (56) is prestressed towards and/or the first clamping element (106) is prestressed towards the central longitudinal axis (14). Tensioning and/or gripping device (10) according to one of claims 1 to 11, wherein it has a clamping device (100) according to one of claims 12 to 15. Pressure piston (54) for a clamping and/or gripping device (10), in particular according to one of claims 1 to 11, with a piston section (56) integrated in the pressure piston (54) and with a clamping device (100) integrated in the pressure piston (54), in particular according to one of claims 12 to 15, and/or with a pressure amplifier (71) integrated in the pressure piston (54).

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