A piston (8) is provided in a motor main body (4). A first motor chamber (9) is provided above the piston (8) and a second motor chamber (10) is provided below the piston (8). A pilot valve element (18) is provided so as to protrude from the piston (8). When a supply/discharge valve (13) is moved to its upper limit position or its lower limit position by the movement of the pilot valve element (18) in an up-down direction, a first valve member (25) of the supply/discharge valve (13) switches between supplying and discharging pressure fluid to and from the first motor chamber (9) and a second valve member (26) of the supply/discharge w valve (13) switches between supplying and discharging pressure fluid to and from the second motor chamber (10).

The oscillation cylinder arrangement (100) comprises a working cylinder (10A) and a piston with a rod (27A), arranged to move therein, and a control valve structure (20) for the working cylinder (10A). The control valve structure (20) incorporates a main valve (24) for transmitting a pressure medium to a first sub-chamber or a second sub-chamber of the working cylinder (10A) for a linear movement (A, B) of the piston, as well as impulse valves (22, 23), and lever arms (25, 26) for controlling them, in order to set the operational state of the main valve (24). Control members (27B) fixed to the piston rod (27A) moving in the working cylinder (10A), the control members (27B) being arranged to contact the lever arms (25, 26) of the impulse valves in order to define the extreme positions of the movement of the piston rod (27A).

A hydraulic boosting and regulating system includes an intensifier circuit and a regulator and employs low leak, low crossover valves.

A pressure booster having arranged therein drive cylinders on both sides of a boosting cylinder is provided with a pair of pilot valves that are actuated when pistons of the drive cylinders abut against the moving ends thereof. A pair of actuation valves switch the supply state of a pressure fluid to pressure chambers of the drive cylinders. When the pilot valves are actuated, the pressure fluid passes through the pilot valves and is supplied to the pair of actuation valves, and the supply state of the pressure fluid is switched.

Mixers for adhesives and sealants that include automatic stroke length adjustment for different sizes and configurations of adhesive and sealant cartridges are disclosed. The mixers include a sensor for detecting when a mixing impeller reaches the top of a cartridge and the bottom of a cartridge, which sends a signal to a main pressure cylinder to reverse direction. The stroke length of the mixer is automatically adjusted without the necessity of manual selection based upon a particular cartridge size.

A pressure booster having arranged therein drive cylinders on both sides of a boosting cylinder is provided with a pair of pilot valves that are actuated when pistons of the drive cylinders abut against the moving ends thereof. A pair of actuation valves switch the supply state of a pressure fluid to pressure chambers of the drive cylinders. When the pilot valves are actuated, the pressure fluid passes through the pilot valves and is supplied to the pair of actuation valves, and the supply state of the pressure fluid is switched.

The oscillation cylinder arrangement (100) comprises a working cylinder (10A) and a piston with a rod (27A), arranged to move therein, and a control valve structure (20) for the working cylinder (10A). The control valve structure (20) incorporates a main valve (24) for transmitting a pressure medium to a first sub-chamber or a second sub-chamber of the working cylinder (10A) for a linear movement (A, B) of the piston, as well as impulse valves (22, 23), and lever arms (25, 26) for controlling them, in order to set the operational state of the main valve (24). Control members (27B) fixed to the piston rod (27A) moving in the working cylinder (10A), the control members (27B) being arranged to contact the lever arms (25, 26) of the impulse valves in order to define the extreme positions of the movement of the piston rod (27A).

Mixers for adhesives and sealants that include automatic stroke length adjustment for different sizes and configurations of adhesive and sealant cartridges are disclosed. The mixers include a sensor for detecting when a mixing impeller reaches the top of a cartridge and the bottom of a cartridge, which sends a signal to a main pressure cylinder to reverse direction. The stroke length of the mixer is automatically adjusted without the necessity of manual selection based upon a particular cartridge size.

A first switching valve that switches between flow passages which allow communication between a first pressure-receiving chamber and a fluid supply device side and flow passages which allow communication between a second pressure-receiving chamber and the fluid supply device side, according to a change in a fluid pressure to be applied, and a second switching valve that is switched to flow passages which apply the fluid pressure to the first switching valve, are provided. The second switching valve includes return device, and is provided to be reciprocatable between an operation position to which the second switching valve is moved by a stroke of a piston and a return position to which the second switching valve is moved by the return device. The piston and the second switching valve are movable independently of each other.

A forklift, a hydraulic cylinder assembly (100) and a hydraulic device thereof are provided. The hydraulic cylinder assembly (100) includes a cylinder (1) having first, second oil inlets (151, 152) and first, second oil outlets (153, 154) therein; a cylinder liner (2) disposed within the cylinder (1) and being moveable between first and second positions, and defining a first oil port (21) and a second oil port (22) therein; a piston (31) disposed within the cylinder liner (2) and being moveable between a third position and a fourth position; a first oil chamber (41) and a second oil chamber (42) are defined by the cylinder (1), the cylinder liner (2) and the piston (31), the first oil chamber (41) is communicated with the first oil port (21), and the second oil chamber (42) is communicated with the second oil port (22).