摘要:
A pneumatic system for operating a drive for a windshield wiper for a rail vehicle, wherein the windshield wiper drive has a piston guide device that has a first connection and a second connection opposite the first connection. At least one piston in the piston guide device carries out linear movements in opposite directions along the main direction of extension of the piston guide device to bring about an alternating rotational movement of the wiper shaft. The pneumatic system has a supply connection for a compressed air supply, wherein the supply connection is connected to the first connection via a first normal operation connection line and a first emergency operation connection line arranged parallel thereto and to the second connection via a second normal operation connection line and a second emergency operation connection line arranged parallel thereto.
摘要:
The invention relates to a control device, in particular for hydraulically controlling components of mobile working machines, consisting of at least one pressure supply connection (P) and a tank or return connection (T) in addition to two user connections (A, B) and control and/or regulating valves (10, 14, 16, 18) which are connected between the individual connections (P, T, A, B), in addition to two control lines (C, Z) which can control at least one of the control and/or regulating valves. Said invention is characterized in that a modular-type functional block (24, 26) is connected to at least one of the control lines (C, Z).
摘要:
According to one aspect of the invention, a hydraulic system includes a controller connected to an operator interface, a pump operable in a first direction for supplying pressurized fluid, and a load-holding valve connected between the pump and a port for connection to an actuator. The load-holding valve may be controlled by the controller and operative in a first position to allow flow to the actuator to operate the actuator against a load and operative in a second position to block load-induced return flow from the actuator to the pump. The controller may be configured to receive a requested actuator stop, to control the first valve to move to the second position in response to the requested actuator stop, to monitor a first system condition in response to the requested actuator stop, to evaluate the monitored system condition with a prescribed criteria, and to determine whether or not to initiate a back-up control routine based on the evaluation.
摘要:
The position controller for a pneumatic field device comprises a current-pressure transducer system having at least two I/P-transducers creating separate pneumatic control signals. Microelectronics creates at least two electrical control signals for the I/P-transducers. A pneumatic signal switching valve has at least two pneumatic inputs for the at least two pneumatic control signals, a pneumatic output for transferring a pneumatic control signal to a working chamber of the pneumatic field device and an electrical switch signal input. The pneumatic signal switch valve comprises a first switch position which blocks a first of the at least two pneumatic control signals and a second switch position which blocks a second of the pneumatic control signals.
摘要:
Provided is a working machine including an upper slewing body, a hydraulic motor, a slewing electric motor, a hydraulic pump, a slewing operation device, a control valve, a communication valve having an open position for bringing a motor outlet-side line into direct communication with a tank or a motor inlet-side line, bypassing the control valve, and a close position for blocking the communication, and a control device which performs (i) determining, as a target value, a pressure generated in the hydraulic motor without the communication valve, or a torque obtained from the pressure, based on an operation state and a slewing state, (ii) determining, as an actual value, a pressure actually generated in the hydraulic motor or a torque obtained from the pressure, and (iii) outputting a torque command based on a value obtained by subtracting the actual value from the target value.
摘要:
A hydraulic valve arrangement, in particular a control valve arrangement, of a hydraulic machine, in particular a hydraulic pump, includes at least one valve with a valve body penetrated by a pressure medium passage. The pressure medium passage has a minimum cross section that gives rise, in normal operation, to a control pressure downstream of the minimum cross section in accordance with a pressure acting at a pressure port of the valve. The minimum cross section is arranged close to a pressure medium passage mouth which is arranged upstream or is configured to be subjected to the high pressure. A hydraulic machine arrangement, in particular a pump arrangement, includes the hydraulic valve arrangement.
摘要:
A hydraulic shifting device for an automatic transmission for engaging and disengaging a parking lock. The shifting device comprises a parking lock cylinder (203) for actuating the parking lock, and a parking lock valve (201) which, for hydraulic control of the parking lock cylinder (203), can be switched to at least first and second shift positions. In this case the hydraulic shifting device comprises a further parking lock valve (202), and the two parking lock valves (201, 202) and the parking lock cylinder (203) are designed and connected with one another in such manner that the parking lock can only be disengaged by pressurizing the parking lock cylinder (203) if the two parking lock valves (201, 202) are each switched to a particular shift position.
摘要:
There are provided: control valves 22-24 that control flow of pressure oil from the hydraulic source 21 to the hydraulic actuators 15-17; electric lever devices 51-53 that output electrical operation signals, which are drive instructions for the hydraulic actuators 15-17, in correspondence to lever operation; and a control unit 25-30 and 50 that controls the control valves 22-24 in correspondence to the operation signals. When the determination unit determines that an operation signal is not within the normal range, the hydraulic actuators 15-17 are allowed to be driven with flow of pressure oil to the hydraulic actuators 15-17 limited more significantly than in a case where it is decided that an operation signal is within the normal range.
摘要:
A system that is usable with a well may include a piston, a primary control subsystem and an override subsystem. The piston actuates the downhole tool, and the primary control subsystem may be connected to at least one hydraulic line in order to move the piston in response to pressure that is communicated to the tool via the hydraulic line(s). The override subsystem may be connected to the hydraulic line(s) to override the primary control subsystem and move the piston in response to pressure communicated to the tool via the hydraulic line(s).
摘要:
A control device for controlling a hydraulic consumer, is equipped with a distributing valve having a control pressure chamber and a control slide that can be displaced against the force of a spring by the build-up of a control pressure in the control pressure chamber. A pilot control valve controls the supply and discharge of control fluid into and out of the control pressure chamber. A release device is used to drive the control fluid out of the control pressure chamber, bypassing the pilot control valve.