This industrial apparatus (2) comprises a pneumatic system (4), a first mechanical device (36) and a second mechanical device (38). The pneumatic system (4) includes: a first pneumatic actuator (6) for commanding the first mechanical device (36), a second pneumatic actuator (8) for commanding the second mechanical device (38), a pneumatic control valve (10) switchable between several states to command of the first and second actuators (6, 8). The control valve (10) comprises an actuation portion (56), movable in translation between: a resting position, corresponding to a first state (51), a first pushed position, corresponding to a second state (S2), and a second pushed position, corresponding to a third state (S3). The first pushed position corresponds to an intermediary position between the resting position and the second pushed position.

This industrial apparatus (2) comprises a pneumatic system (4), a first mechanical device (36) and a second mechanical device (38). The pneumatic system (4) includes: a first pneumatic actuator (6) for commanding the first mechanical device (36), a second pneumatic actuator (8) for commanding the second mechanical device (38), a pneumatic control valve (10) switchable between several states to command of the first and second actuators (6, 8). The control valve (10) comprises an actuation portion (56), movable in translation between: a resting position, corresponding to a first state (51), a first pushed position, corresponding to a second state (S2), and a second pushed position, corresponding to a third state (S3). The first pushed position corresponds to an intermediary position between the resting position and the second pushed position.

A hydraulic control valve maintains the pressure at a control port at a desired percentage of the pressure at two other ports as the pressure at the two other ports varies. Upon the pressure at the control port reaching a predetermined pressure setting, a fourth port will open to maintain the control port at a second desired percentage of the two other ports.

A hydraulic control valve maintains the pressure at a control port at a desired percentage of the pressure at two other ports as the pressure at the two other ports varies. Upon the pressure at the control port reaching a predetermined pressure setting, a fourth port will open to maintain the control port at a second desired percentage of the two other ports.

It is made possible to suppress variations of the speed of an actuator into which a regeneration flow rate flows, regardless of variations of the regeneration flow rate caused by posture changes of the front part and to enhance the operability when the front part moves in the free fall direction, and hydraulic fluid discharged from an actuator driving the front part is regenerated. Accordingly, a controller 19 of a hydraulic system is provided with a regeneration control calculation section 19b, and a pump flow rate control calculation section 19c, and when the regeneration control calculation section controls a regeneration valve 12 to perform regeneration, the pump flow rate control calculation section controls a pump flow rate regulation device 20 to increase the delivery flow rate of a hydraulic pump 1 as the angle of an arm 16 approaches the vertically downward direction based on posture information about the arm 16 acquired by an inertial measurement unit 31.

Provided is a hydraulic drive system for a work machine configured with a single solenoid proportional valve for a regeneration circuit, wherein substantially the same actuator speed can be secured irrespective of whether or not hydraulic fluid discharged from a hydraulic actuator is regenerated for driving of another hydraulic actuator. The hydraulic drive system includes: a regeneration line that connects a bottom-side hydraulic chamber of a hydraulic cylinder 4 to a portion between a hydraulic pump device 50 and a second hydraulic actuator 8, and a regeneration flow rate adjustment device that supplies, at an adjusted flow rate, at least part of the discharged hydraulic fluid to a portion between the hydraulic pump device 50 and the second hydraulic actuator; a discharge flow rate adjustment device that discharges, at an adjusted flow rate, the discharged hydraulic fluid to a tank; one electric drive device 22 that simultaneously controls the regeneration flow rate adjustment device and the discharge flow rate adjustment device; and a control unit 27 that outputs a control command to the electric drive device in such a manner that falling speed of a first driven body does not vary significantly, irrespective of the magnitude of the regeneration flow rate caused by the regeneration flow rate adjustment device.

An in-port sequencing valve configured to be utilized with a clamping device of a workpiece clamping system having a fixture plate, a number of fixture datums, and a number of clamping devices. The in-port sequencing valve includes a housing, a pre-load adjuster, a valve spring, and a valve piston. The pre-load adjuster is configured to be set to a selected valve activation setting. The valve spring is compressed an amount corresponding to the valve activation setting. The valve piston is configured to be shifted from a closed position to an open position when a force due to hydraulic fluid pressure overcomes a threshold spring force of the valve spring corresponding to the valve activation setting. The in-port sequencing valve can be set to a selected valve activation setting so that the clamping devices clamp the workpiece in a selected order according to the valve activation setting.

An in-port sequencing valve configured to be utilized with a clamping device of a workpiece clamping system having a fixture plate, a number of fixture datums, and a number of clamping devices. The in-port sequencing valve includes a housing, a pre-load adjuster, a valve spring, and a valve piston. The pre-load adjuster is configured to be set to a selected valve activation setting. The valve spring is compressed an amount corresponding to the valve activation setting. The valve piston is configured to be shifted from a closed position to an open position when a force due to hydraulic fluid pressure overcomes a threshold spring force of the valve spring corresponding to the valve activation setting. The in-port sequencing valve can be set to a selected valve activation setting so that the clamping devices clamp the workpiece in a selected order according to the valve activation setting.

The invention relates to a downhole tractor having at least one hydraulic drive section, comprising a first hydraulic supply line for actuating at least one hydraulic cylinder for actuating at least one tractor arm and a second hydraulic supply line for driving at least one hydraulic motor for rotating at least one tractor wheel. The downhole tractor further comprises a hydraulic power pack configured for supplying hydraulic fluid to the hydraulic supply lines. The hydraulic power pack comprises a pressure-setting valve provided in between the first hydraulic supply line and the second hydraulic supply line, wherein the pressure-setting valve is configured for feeding excess hydraulic fluid in the first hydraulic supply line to the second hydraulic supply line to increase the speed of the downhole tractor.

The invention relates to a downhole tractor having at least one hydraulic drive section, comprising a first hydraulic supply line for actuating at least one hydraulic cylinder for actuating at least one tractor arm and a second hydraulic supply line for driving at least one hydraulic motor for rotating at least one tractor wheel. The downhole tractor further comprises a hydraulic power pack configured for supplying hydraulic fluid to the hydraulic supply lines. The hydraulic power pack comprises a pressure-setting valve provided in between the first hydraulic supply line and the second hydraulic supply line, wherein the pressure-setting valve is configured for feeding excess hydraulic fluid in the first hydraulic supply line to the second hydraulic supply line to increase the speed of the downhole tractor.