An oil pressure mobile device for a wood working machine is provided in a wood working machine, including a power mechanism and a lifting mechanism. The power mechanism is provided with an oil hydraulic cylinder having its inner wall annularly mounted with a piston fixed with a telescopic rod. The lifting mechanism is disposed with two wheel pressing plates at the underside of the wood working machine. The two wheel pressing plates are jointly provided with a connecting link connected with the telescopic rod, and respectively installed with a moving wheel. Thus, the telescopic rod is driven by the power mechanism to extend or retract and actuate the wheel pressing plates to produce angular variation to make the moving wheels stretch out of the housing of the wood working machine for facilitating shifting of the wood working machine with less labor.

The disclosure provides an integral hydraulic system, which includes a valve board, a lift cylinder and a reservoir connected into one integral valve body, wherein the integral valve body is further connected to an electric motor and a hydraulic gear pump, so as to form a complete power unit that includes all the valves utilized in the different functions that control a hydraulic fluid circuit in lifting and lowering of a plunger rod of the lift cylinder.

A fluid pressure cylinder comprises a rod insertion hole formed in a piston member, an auxiliary rod provided to a head side wall member so as to be inserted into the rod insertion hole, an open/shut valve mechanism for detection, and a fluid passage that is opened and shut by the open/shut valve mechanism. The open/shut valve mechanism includes a valve body reception hole formed in the auxiliary rod, a valve body that is movably held in the valve body reception hole and that has a recessed engagement portion on its external peripheral portion, and a spherical body mounted on the auxiliary rod so as to engage with the recessed engagement portion; when the piston member has reached a set shifting position, the valve body is changed over to the closed position or to the opened position due to cooperation between the spherical body, the recessed engagement portion, and the inner peripheral wall portion of the rod insertion hole.

The invention relates to a hydraulic cylinder, for example for use in a hydraulic tool, comprising at least one piston/cylinder combination composed of a cylinder body and a piston accommodated in said cylinder body and provided with a piston rod that projects from said cylinder body, wherein the cylinder body and the piston body define a first cylinder chamber while the cylinder body, the piston body and the piston rod define a second cylinder chamber, and wherein during operation the piston performs alternating forward and return operational cycles under the influence of a fluidum under pressure that is conducted to the first and the second cylinder chamber through a first and a second line, respectively, and a control valve which regulates the supply of a fluid under pressure through the first or the second line to the piston/cylinder combination.

In one embodiment, a steering system for an agricultural implement system includes a first actuating cylinder configured to rotate a first track relative to an implement frame where the first actuating cylinder is connected to a first frame of the first track, and a second actuating cylinder configured to rotate a second track relative to the implement frame where the second actuating cylinder is connected to a second frame of the second track. The steering system also includes a first fluid control conduit extending to a cap end of the first actuating cylinder, a second fluid control conduit extending between a rod end of the first actuating cylinder and a rod end of the second actuating cylinder, a third fluid control conduit extending to a cap end of the second actuating cylinder, and a steering control valve in fluid communication with the first and third fluid control conduits.

A steering device includes: a cylinder demarcated into first and second chambers by a piston; a main valve having first and second shuttle chambers; a hydraulic source having first and second discharge ports; a first oil passage configured to connect the first chamber and the first shuttle chamber; a second oil passage configured to connect the second chamber and the second shuttle chamber; a third oil passage configured to connect the first shuttle chamber and the first discharge port; a fourth oil passage configured to connect the second shuttle chamber and the second discharge port; and a tank connected to the main valve via the third oil passage and the fourth oil passage. One of the first shuttle chamber and the second shuttle chamber of the main valve is in an opened state when the hydraulic source is stopped.

An autonomous hydraulic expansion and contraction apparatus comprises a fixing unit, a cylinder unit, a support unit, a piston unit, a valve unit and oil supply parts. By controlling the expansion and contraction length of the support part by a simple manipulation of the valve part by moving the lever, the autonomous hydraulic expansion and contraction apparatus can be easily expanded and contracted to the combined length of the expansion and contraction equipment, and additionally, the convenience of use can be enhanced.

A flexible pneumatic actuator assembly includes a front base, a rear base, a length of flexible tubing having a front end secured to the front base and a rear end secured to the rear base, a flexible piston rod extending through an aperture in the front base and into an internal volume of the length of flexible tubing, and a piston secured to the piston rod within the internal volume of the length of flexible tubing. The piston is configured to maintain an air tight seal against an inner wall of the tubing upon bending of the tubing in a region including the piston.

A fluid actuated linear drive which includes a drive housing and a drive member which is movable relative to the drive housing. The drive force which is necessary for producing the drive movement is provided by a drive fluid which can be fed and discharged through housing channels of the drive housing. The housing channels each with a lateral coupling opening run out at a housing side surface of the drive housing. An L-shaped attachment coupling part which in the position of use is assembled on the drive housing has a coupling limb which is assigned to a housing rear surface and which is provided with two axial coupling openings. The axial coupling openings are in connection with lateral coupling openings via coupling channels. Hence there is the possibility of using the axial coupling openings for the feed and discharge of the drive fluid.

A fluid actuated linear drive includes a drive housing and a drive member which is movable between two stroke end positions. The drive member has a drive unit with a drive piston which divides off two drive chambers from one another, the drive chambers via two housing channels being connected to axial housing coupling openings which are arranged on a housing rear side. A multi-function module is built onto the housing rear side in a position of use and includes components of an external end position setting device for the drive member and is furthermore provided with module block channel systems which communicate with the housing channels and can be used for the feed and discharge of a drive fluid when the multifunction module is built onto the drive housing in the position of use.