Abstract: An adjustable tire inflation assembly for precisely inflating a tire to a desired pressure includes a tire inflation fitting that is fluidly attachable to a valve stem on a tire for inflating the tire. A pressure adjustment unit is integrated into the tire inflation fitting that is settable between a minimum pressure and a maximum pressure. The pressure adjustment unit senses the pressure within the tire when the tire is being inflated with the tire inflation fitting. A light emitter is coupled to the tire inflation fitting and the light emitter is turned on when the pressure adjustment unit senses air pressure within the tire inflation unit that matches the pressure to which the pressure adjustment unit is set. In this way the light emitter alerts the user that the tire has been inflated to the desired pressure.

Abstract: An air pressure maintenance apparatus and method uses one or more high-pressure gas storage tanks coupled to an inflation hose via a calibrated rigid measurement chamber and automated system of valves to permit rapid inflation of a tire or other inflatable device to an accurate target pressure accounting for temperature effects, and recording accurate pre- and post-inflation pressure for analysis of deflation over time.

Abstract: Pressure sensor systems and methods of assembling pressure sensor systems that reduce the need for accurate placement of a pressure sensor die in a pressure sensor package, reduce leakage in pressure sensor systems, and provides a consistent attachment of a pressure sensor die to a package.

Abstract: Example implementations relate to pumps with pre-charged fluid. In some examples, a pump may comprise a first valve connected to an inlet of the pump by a first clip, a second valve connected to an outlet of the pump by a second clip, and a compression release mechanism to relieve compression forces generated on a fluid included in the pump in response to the pump being connected to a manifold, where the pump is pre-charged with the fluid.

Abstract: A clutch system includes a clutch plate and a reservoir coupled with the clutch plate. The reservoir is configured to receive bailed excess fluid from the clutch upon rotation of the clutch plate. The clutch system also includes a hydraulic control valve fluidly coupled with the clutch plate and the reservoir. A first fluid flow path is defined between the reservoir and the clutch plate. Moreover, the hydraulic control valve includes an orifice fluidly coupled with the reservoir and a lube valve configured to move between a closed position and an open position. Additionally, a cavity is defined in the hydraulic control valve. Finally, the movement of the lube valve between the open position and the closed position is controlled using the fluid from the reservoir which flows though the orifice and into the cavity.

Abstract: A valve, in particular a proportional pressure regulating valve, has a valve piston (12) longitudinally movable in a valve housing (10) for alternately releasing and connecting a user connection (A) to a pressure supply port (P) or a tank connection (T). The valve piston can be actuated by an actuating magnet (14) that produces a dither signal during operation. The valve piston (12) reaches a floating position within the valve housing (10) by a hydraulic lift limitation for the receipt of the dither signal.

Abstract: A first valve is disposed in an oil passage through which the engaging pressure generated by a linear solenoid valve is supplied to A second brake. The first valve is closed when the second brake is released, so as to close the oil passage, and is opened when the second brake is engaged, so as to open the oil passage. A second valve is disposed in a lubricating oil passage through which lubricating oil is supplied to the second brake, and communicates with the linear solenoid valve. The second valve is opened when the engaging pressure is supplied from the linear solenoid valve, so as to open the lubricating oil passage, and is closed when no engaging pressure is generated by the linear solenoid valve.

Abstract: A hydraulic control circuit includes a first pressure regulating valve for regulating a pump discharge pressure, a second pressure regulating valve for adjusting a pilot pressure to a torque converter pressure, and a first oil passage that connects an output port of the first pressure regulating valve and a torque-converter input-side oil passage, the second pressure regulating valve having an input port connected to the first oil passage through a second oil passage, a drive port connected to the first oil passage through a third oil passage, a spool axially displaced according to a drive pressure inputted into the drive port for regulating the torque converter pressure, and an output port. A throttle is provided between the connection section of the first and third oil passages and the connection section of the first and second oil passages, for adjusting the torque converter pressure to an appropriate pressure.

Abstract: The proportional control valve for a fuel pump has a metering assembly within a tightly fit bore and a vent valve. The metering assembly includes a metering piston assembly, a piston biasing spring, an armature and a vent valve. The vent valve, such as a ball, is affixed to the armature and the metering piston assembly is configured around the vent valve in a manner that couples the metering piston to the armature. The metering piston assembly comprises a metering piston and a vent valve seat, permanently joined together, which contain a seal and a seat surface respectively between which the vent valve is permitted to move during the operation of the proportional control valve.

Abstract: An electroproportional pressure control valve of cartridge-type construction is screwed into a housing bore of a hydrostatic pump. The cartridge includes an adjusting pressure port, a pump port, and a tank port. The adjusting pressure port is relieved to the tank port in a normal position of a spring-biased valve plunger of the pressure control valve. A connection from the pump port to the adjusting pressure port is opened counter to the force of the spring by increasing a current of an electromagnet and increasing the pump pressure at the pump port. The spring, the electromagnet, and the resultant force of the pump pressure act along a common axis of movement of the valve plunger. A first nozzle connects the adjusting pressure port to an adjusting pressure chamber. A second nozzle connects the adjusting pressure port to the tank port.

Abstract: A system and method is provided for an adjustable spring plunger bumper with high initial load and low final load. The spring plunger bumper includes an exterior body surrounding a plunger. The plunger has a plunger indent into which a displacement ball is induced by a ramp sleeve biased by a ramp sleeve spring. As the plunger is displaced relative to the exterior body, the displacement ball contacts a lower displacement ball inclined surface, which provides a high initial load resisting the displacement of the plunger. However, as the displacement of the plunger continues, the displacement ball comes into contact with a smooth lower displacement ball indent surface which provides a lower load. A return spring is positioned between the plunger and the exterior body to return them to their initial position relative to each other when the displacement of the plunger is removed.

Abstract: Fluid regulators are disclosed. An example a valve body including an inlet, an outlet, and an aperture disposed between the inlet and the outlet, the outlet includes surface structures to increase a uniformity of a flow pattern of fluid flowing through a cross-section of the outlet.

Abstract: A paint circulation system includes: a main line; a branch line; a supply pump; and a pressurization device for storing pressure of the paint in a high-pressure state in which the pressure of the paint is higher than a predetermined pressure, and for applying pressure to the paint inside of the branch line in a low-pressure state in which the pressure of the paint is lower than the predetermined pressure, in which sedimentation of the paint is prevented by driving the supply pump so that the high-pressure state and the low-pressure state occur, to cause flow sending the paint inside of the branch line from a side of the painting device to a side of the main line using a pressure difference between the predetermined pressure in the low-pressure state and the pressure of the paint.

Abstract: A hydraulic depth-control device for a submersible body comprises: a variable-volume ballast space, a pressure accumulator comprising a hydraulic chamber and a gas chamber, which chambers are separated by a deformable or mobile wall, the gas chamber containing a gas at an absolute pressure higher than atmospheric pressure, a hydraulic pump coupled to an electric motor, the hydraulic pump having a suction inlet connected to the ballast space and a delivery outlet connected to the hydraulic chamber of the pressure accumulator, a return hydraulic circuit connecting the hydraulic chamber of the pressure accumulator to the ballast space via an electrically operated valve, and a hydraulic fluid arranged in the ballast space, the hydraulic pump, the hydraulic chamber of the pressure accumulator and the return hydraulic circuit.

Abstract: A system including a pressure regulator configured to regulate a flow of pressurized fluid in a hydrocarbon extraction system, the pressure regulator, including a housing having a chamber, a biasing system configured to provide a biasing force, a sensing piston disposed within the chamber, wherein the sensing piston is responsive to pressure within the chamber and the biasing force from the biasing system, and a supply seal plate comprising a first fluid supply passageway configured to reduce oscillations of the sensing piston.

Abstract: An apparatus for detecting wear in a flush valve includes at least one programmed controller. The flush valve comprises at least one pressure sensor and a valve element, and operates when an internal pressure causes the valve element to open. The controller is programmed to record at least one water pressure detected within the flush valve with the at least one pressure sensor after at least one operation of the flush valve, record a water pressure detected within the flush valve after a subsequent operation of the flush valve, and determine if the flush valve is faulty based at least partially on a comparison between the at least one water pressure detected after the at least one operation of the flush valve and the water pressure detected after the subsequent operation of the flush valve.

Abstract: Dual directional latch devices or connectors are described wherein a first connector component and a second connector component have a first latched position and a second latched position when moving in a first direction and wherein movement in a second direction is also possible when a restriction feature is overcome. As described, opposing magnetic forces, pneumatic pressure, spring force, and a crushable force may be incorporated so that further movement in the second direction must overcome the restriction feature. The dual direction latch devices may be used with articles of manufacture such as with implantable medical devices, door panels, airplane panels, and drilling devices to name a few.

Abstract: An oil pump includes a relief valve. The relief valve adjusts a pump discharge pressure depending on a differential pressure between the pump discharge pressure and a back pressure chamber pressure. An electromagnetic switching valve includes a movable member moved electromagnetically. The movable member brings a ball valve element selectively into a state pressed onto a valve seat portion, to selectively close and open an oil passage. The electromagnetic switching valve selectively supplies the pump discharge pressure to a back pressure chamber of the relief valve and drains the back pressure chamber of the relief valve by selectively opening and closing the oil passage. A pilot valve is disposed downstream of the electromagnetic switching valve, and operates upon receipt of the pump discharge pressure or the back pressure chamber pressure, and controls an oil pressure supplied to the back pressure chamber of the relief valve.

Abstract: An oil pressure relief valve for use in the oil pump lubrication system of an internal combustion engine is controlled by both oil pump outlet pressure and by pilot pressure from a pilot valve which is selectively applied by a control member, preferably a two-way valve that is operated by the engine control module. The pilot valve selectively supplies one of the oil pump outlet pressure or the engine gallery pressure to the control member which selectively supplies pilot valve pressure to the oil pump pressure relief valve which has a single piston. The pilot valve includes first and second pistons for selectively controlling back pressure from the pressure relief valve and for managing changes in oil pressure due to changes in the engine gallery to maintain a virtually constant pressure even as oil pump speed increases when the control member connects the pilot valve to the pressure relief valve resulting in a fuel economy benefit and improved control of the oil pump pressure.

Abstract: An apparatus for regulating the flow of a fluid from a source to a target location comprises a housing defining a fluid inlet configured to communicate with a fluid source and a fluid outlet configured to communicate with a target location, and a flow path extending between the fluid inlet and fluid outlet. An inlet valve assembly is mounted in the flow path and comprises a valve seat and a valve member configured to cooperate with the valve seat to regulate flow through the flow path. A balance arrangement is provided and is configured to balance the effect of fluid pressure acting on the inlet valve assembly.

Abstract: This invention relates to an aerating device for a fuel system, and in particular, to an aerating device for a fuel system supplying fuel to an engine from a fuel tank. The invention includes, for example, a solenoid valve accessing a flow path to the fuel tank, and a control unit opening a closing the solenoid valve, such that opening of the solenoid valve permits fuel and air to flow back through the flow path to the fuel tank and naturally separate.

Abstract: A method for correcting an actuator characteristic of a clutch actuator for a friction clutch of a vehicle transmission after the commissioning of the vehicle. The actuator characteristic relates a first desired variable, such as a desired clutch pressure, to a second desired variable, such as an desired actuator current. The method includes approaching a quasi-steady-state operating point of the friction clutch. In addition, a deviation is detected between the first desired variable and an actual variable of the friction clutch. Also, a correction function is set up for the actuator characteristic according to the deviation.

Abstract: The invention relates to a solenoid valve including an electromagnet (17, 4, 3, 10) made of a flat movable core (10), a fixed core (3) and a coil (17), the solenoid valve comprising a body (4) which also belongs to the electromagnet and includes an opening (23) located at the rear of the body (4), opposite the supply opening (18), for inserting the flat movable core (10), the fixed core (3) and the coil (17). The body (4) is secured to a retaining ring (8) made of a non-magnetic material, a flat spring (9) being compressed between the retaining ring (8) and the flat movable core (10).

Abstract: A pilot type pressure regulator has: a primary port to which air is supplied from the outside; and a secondary port discharging air regulated by a main valve body provided to a main valve shaft. A main valve diaphragm abutting on an abutting end surface of the main valve shaft partitions an inner space into a secondary pressure chamber communicating with the secondary port and a pilot pressure chamber to which pilot pressure is supplied. This pressure regulator has an exhaust mechanism exhausting air from the secondary pressure chamber to the outside when pressure of the secondary port exceeds a set value. In the exhaust mechanism, a stopper holding a sealing material in a guide hole is inserted from the side close to a main valve hole, that is, an inner end portion.

Abstract: An electronic control unit monitors pressure conditions present at the input to the steering system and other vehicle data signals and then provides override control of a hydro-mechanical flow control device. An electro-hydraulic valve is connected to the supply side of the hydro-mechanical flow control device and reacts to the electronic monitoring of pressure and other vehicle data to alter the counter-balancing forces within the hydro-mechanical flow control device. This causes a by-pass diversion of steering fluid to the source by the hydro-mechanical flow control device and thereby relieves backpressure on the pump when relatively little steering assist is required to be provided by the steering system. The control of steering fluid diversion at such times results in a significant reduction in parasitic losses within the steering system and improves the operating and fuel efficiency of the vehicle.

Abstract: A sprinkler pressure regulator module has a compact arrangement with a shiftable member having an upper cavity for receiving water flow debris, and a portion of a bypass valve may reciprocate therein. The module includes a stator plate directing water into a drive mechanism, such as a turbine drive mechanism. The shiftable member receives fluid flow from a radially outboard direction and is sealed with a cup portion receiving the shiftable member to define a cup cavity. A module exterior surface is separated from a sprinkler housing to define a vent cavity. A pressure release vent communicates with the cup cavity, a vent channel between the cup portion and the exterior surface, the vent cavity, and the exterior environment. The vent cavity and cup portion provide receptacles for debris deposit. Ribs around an opening of the vent channel with the vent cavity generally prevent debris from entering the vent channel.

Abstract: A valve assembly is provided. The valve assembly comprises a housing having an inlet, a first outlet, and a passageway extending therebetween, the passageway having a first inner diameter at the inlet and a second inner diameter at the first outlet, a first poppet valve disposed in, and adapted to selectively seal, the inlet, a second poppet valve disposed in, and adapted to selectively seal, the first outlet, the second poppet valve coupled to the first poppet valve, and a biasing member coupled to the second poppet valve, the biasing member adapted to exert a force sealing the second poppet valve.

Abstract: A gas pressure regulator is provided that includes a body defining a front portion and opposed side portions. A first gas pressure indicator is mounted to a lower end of the front portion of the body, and a second gas pressure indicator mounted to an upper end of the front portion of the body, wherein the first gas pressure indicator and the second gas pressure indicator are stacked in a vertical configuration. Additionally, a pressure adjustment knob is mounted to one of the side portions of the body in one form of the present disclosure.

Abstract: A pressure regulator is provided. In one embodiment, the pressure regulator includes a body having an internal cavity for receiving a pressurized medium and inlet and outlet ports that enable a pressurized medium to enter the internal cavity at a first pressure and exit at a second pressure. The exemplary pressure regulator also includes a control piston disposed within the internal cavity that is configured to move in response to a change in pressure within the internal cavity. The pressure regulator of this embodiment also includes a damping feature within the internal cavity that is configured to oppose the movement of the control piston. Other embodiments of pressure regulators and systems are also provided.

Abstract: Diaphragm assemblies for use with fluid control devices are described. An example diaphragm assembly includes a body defining a plurality of chambers to be fluidly coupled to an outlet pressure of a fluid control device. Each of the chambers is spaced along a stem at least partially disposed in the chambers, and the stem is to move to control a flow of fluid through the fluid control device. Additionally, the example diaphragm assembly includes a first plurality of diaphragms, each of which is disposed in a corresponding one of the chambers, and each of which is coupled to the stem to move the stem in response to the outlet pressure of the fluid control device.

Abstract: A closing element is for a valve assembly of a compressor unloader, the compressor including a casing with a compression chamber, the unloader including a housing defining a chamber. The valve assembly has a base between the compression and unloader chambers, a passage connecting the two chambers, a seat about the passage, and a stem bore within the base having a control chamber. The closing element includes a main body movably disposed within the stem bore and having a sealing surface disposeable against the valve seating surface to obstruct the valve passage and a control end surface within the bore control chamber A sealing member disposed about the main body prevents flow between the control chamber and the valve passage. The main body and/or the sealing member is configured such that the main body is radially moveable to align the body sealing surface with the valve seat.

Abstract: A control device is provided for use with a pneumatic pump for generating output pressure, a pressure sensor for indicating the level of the output pressure, and an input device for receiving a target pressure level input by a user. The control device is configured to monitor the sensed output pressure during a pressurizing condition in which the pump provides increasing output pressure. The control device is further configured to maintain the pressurizing condition while the level of the sensed output pressure increases past the target pressure level, and to terminate the pressurizing condition in response to the sensed output pressure increasing to a level that exceeds the target pressure level by a predetermined differential value.

Abstract: Featured is an automatic high-negative pressure relief valve and its use in combination with an apparatus for draining fluid from a body. In broad terms the negative pressure relief valve includes a biasing mechanism, a moveable member acted upon by the biasing mechanism and a seating surface. When the pressure within a chamber, in which a portion of the relief valve is in fluid communication with, is less than a predetermined negative pressure, the moveable member is moved by the biasing mechanism to sealing engage the seating surface and when the pressure is at or above the predetermined value, the restoring force of the biasing mechanism is overcome and the moveable member moves away from the seating surface. In an exemplary embodiment, the biasing mechanism is a spring, diaphragm or wave washer.

Abstract: A valve for limiting the tank pressure in a motor vehicle, comprising a first line (1) and a second line (2) which may establish a flow connection in which at least one body (3, 4) may be moved relative to another body (4, 3), whereby the movable body (3, 4) lifts up from a sealing seat (5), with regard to the object of adjusting the tank pressure using a compact design is characterized in that a first body (3), a second body (4), and the sealing seat (5) as a whole form a movable unit (6).

Abstract: This pressure regulator is specifically designed to operate with a portable compressed gas cartridge thus reducing the high vapor pressure found in compressed gas cartridges down to a substantially consistent outlet pressure. Due to the nature of the crowded regulator art, the soon to be embodied pressure regulator has been specifically embodied for use in the portable compressed gas cartridge harnessing art and this specific use is carried into the claims. Exemplified in the pressure regulator embodiments is a reduced amount of components over existing designs. Additionally, safety and reliability features have been integrated into the design and will shortly be taught in the following paragraphs. A burp-off feature in all embodiments will be exemplified that vents back-pressure spikes as well as a method of adjusting the burp-off back-pressure spikes independent of regulated pressure in some embodiments.

Abstract: A diaphragm valve having a first chamber and a second chamber, which is separated from the first chamber by means of a valve member which cooperates with a valve seat. A first connecting conduit situated in the vicinity of the valve seat feeds into the first chamber. To enable the diaphragm valve to be used as a pressure control valve, the valve member has a through conduit that connects the first connecting conduit to the second chamber of the pressure control valve when the pressure control valve is closed.

Abstract: A device for regulating a flow of gas toward user equipment, which comprises a first regulation stage and a second regulation stage arranged downstream in a direction of flow of the gas to be controlled, further comprising a flow limiter interposed between the first and second regulation stages and adapted to intervene if the second stage malfunctions.

Abstract: The present invention relates to a device for regulating the flow rate and/or the pressure of a fluid transferred from a high-pressure reservoir (H) to a reservoir (S). A first valve (1) provided with a control (2) is mounted in a pipe (10, 11, 12) connecting the two reservoirs (H, S). A Laval nozzle (3) located downstream of the first valve (1) is provided with an electrical pressure-drop sensor (4). A second valve (5) provided with a control (6) is connected between the downstream part of the Laval nozzle and an exhaust orifice (R). A micro-programmed system (7), designed to receive the values read by the pressure-drop sensor (4) and to drive the two controls (2, 6) of the two valves (1, 5) makes it possible to regulate the flow rate and/or the pressure of the fluid transferred from the first reservoir (H) to the second reservoir (S).

Abstract: The regulator connects to a high pressure fluid supply and regulates the pressure to a downstream apparatus. If an over-pressure occurs, it is vented to atmosphere. An elongate control stem engages a supply seal assembly and a vent seal assembly and moves axially with respect to these seal assemblies to achieve regulation and venting. During high fluid flow, the supply seal assembly and the vent seal assembly are not in the fluid flow path of the regulator which makes the seal assemblies more resistant to erosion from fluid flow. The fluid flow path through the regulator is partially in hollow passageways in the elongate control stem.

Abstract: Featured is an automatic high-negative pressure relief valve and its use in combination with an apparatus for draining fluid from a body. In broad terms the negative pressure relief valve includes a biasing mechanism, a moveable member acted upon by the biasing mechanism and a seating surface. When the pressure within a chamber, in which a portion of the relief valve is in fluid communication with, is less than a predetermined negative pressure, the moveable member is moved by the biasing mechanism to sealing engage the seating surface and when the pressure is at or above the predetermined value, the restoring force of the biasing mechanism is overcome and the moveable member moves away from the seating surface. In an exemplary embodiment, the biasing mechanism is a spring, diaphragm or wave washer.

Abstract: A combined fluid pressure reducing and relief valve having aligned inlet and outlet connections, a pair of abutting rotary disc valve sets each having an inboard stationary and an outboard rotary ceramic disc which are relatively rotatable against each other to expose and close openings therein. The sets are regulated by a pressure sensitive member comprising a diaphragm flush with a piston which is movable against a spring in response to low pressure fluid in the valve whereby one set opens until that pressure reaches a “set” pressure. If the low pressure increases to a “initial relief pressure,” further movement of the pressure sensitive member results. Finally with still further movement the low pressure side reaches a “relief pressure” whereby the other rotary valve set opens while the first is closed and remains open until the low pressure side is reduced to below the “set” pressure.

Abstract: A microvalve device includes a first plate, a second plate and a third plate. The second plate is connected between the first plate and the third plate. The second plate contains a stationary element and a moveable plate valve slider element. The slider element variably restricts the flow of a fluid through the microvalve device. The second plate defines a first supply port, an output conduit, and a return port. In a pressure increase position, the slider element allows the fluid to flow from the first supply port to the output conduit. In a pressure hold position, the slider element isolates the output conduit from both the first supply port and the return port. The pressure decrease position allows fluid to flow from the output conduit to the return port. Pressure from the output conduit acts against a first axial end face of the slider element.

Abstract: Disclosed is a device for regulating the pressure and/or flow of a gas stream, which device comprises a housing (9, 109) which is provided with a pressure-regulating chamber (4, 104), at least part of whose wall comprises a diaphragm (10, 110), which diaphragm (10, 110) is subjected, on the side remote from the pressure-regulating chamber (4, 104), to an adjustable prestressing force, the pressure-regulating chamber comprising an inlet opening (3, 28, 128) for a gas and an outlet opening (5, 29, 129) for a gas, it being possible for at least one of the openings (3/5, 28/29, 128/129) to be completely or partially closed off with the aid of a displaceable closure member (15, 115) which is connected to the diaphragm (10, 110) in such a manner that the position of the closure member is dependent on the displacement of the diaphragm.

Abstract: A fluid pressure controller has an air supply valve plug displaceable under an action of pilot pressure of a pilot chamber. When the air supply valve plug is seated on a seat section, fluid communication between a supply port and a regulator port is interrupted. Further, the fluid pressure controller has a solenoid valve. When electric power supply to the solenoid valve is interrupted, the solenoid valve is opened to generate pilot pressure applied to the air supply valve plug by the original pressure of pressurized fluid introduced from the pressurized fluid supply source to the supply port.

Abstract: The precision regulator connects to a high pressure fluid source and regulates the pressure to a downstream apparatus. If an overpressure occurs, it can be vented to atmosphere. An elongate control stem engages a supply seal assembly and a vent seal assembly and moves axially and past these seal assemblies to achieve regulation and venting. The set point of the regulator can be adjusted by rotation of an adjustment knob that adjusts the position of the elongate control stem relative to the supply seal assembly and the vent seal assembly. Regulation is achieved primarily by use of a sensor piston which transfers fluid pressure from a regulated port to the sensor piston which is opposed by a spring. Both the supply seal assembly and the vent seal assembly rely upon an o-ring and a seal ring to achieve a seal with the outside circumference of the control stem. The o-ring is compressed and distorted, thus exerting forces against the seal ring to achieve a better seal.

Abstract: The regulator connects to a high pressure fluid supply and regulates the pressure to a downstream apparatus. If an over-pressure occurs, it is vented to atmosphere. A segmented body reduces production costs. An elongate control stem engages a supply seal assembly and a vent seal assembly and moves axially with respect to these seal assemblies to achieve regulation and venting. Both the supply seal assembly and the vent seal assembly are bi-directional and operate when forces are applied from opposing directions.

Abstract: The present invention relates to control of a hydraulic piston/cylinder unit, in particular a multi-disc clutch having a control valve which can be moved into an open and a closed position, a first connecting line connected to the hydraulic piston/cylinder unit and a second connecting line connected to a pressure feed. The first and second connecting lines are in communication with the control valve. The first connecting line is designed such that when subjected to pressure, a force acting in the closed position can be generated on the control valve. The control further possesses a first control line which is in connection with the control valve such that when subjected to pressure, a force acting in the open position can be generated on the control valve. Furthermore, a restrictor element is provided whose inlet can be connected to the pressure feed and whose outlet is in communication with a pressure store and the first control line.