A hydraulic fluid pressure amplifier system includes a boost cylinder assembly, an energy storage device in fluid communication with the boost cylinder assembly, and a working cylinder assembly. The boost cylinder assembly is configured to selectively receive a plunger member into a boost cylinder, wherein movement of the plunger member received in the boost cylinder compresses a charge fluid within a blind side volume of the boost cylinder from a first fluid pressure to an amplified fluid pressure greater than the first pressure. The working cylinder assembly is selectively operable responsive to receiving a source hydraulic fluid having a nominal fluid pressure less than the amplified fluid pressure for effecting the movement of the plunger member into the boost cylinder. The energy storage device is operable to selectively receive and store a portion of the charge fluid compressed to the amplified fluid pressure.

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).

A pressure booster includes a pressure boosting unit and a bypass unit. The pressure boosting unit includes an input port connected to the side of a fluid supply source and an output port connected to the side of a tank. The pressure boosting unit boosts the pressure of a pressurized fluid supplied to the input port and outputs the pressure-boosted pressurized fluid from the output port. The bypass unit includes a bypass flow path having one end connected to the fluid supply source side and the other end connected to the output port side. The bypass flow path is provided with a bypass check valve configured to block the flow of the pressurized fluid from the output port side to the fluid supply source side.

A pressure booster includes a pressure boosting unit and a bypass unit. The pressure boosting unit includes an input port connected to the side of a fluid supply source and an output port connected to the side of a tank. The pressure boosting unit boosts the pressure of a pressurized fluid supplied to the input port and outputs the pressure-boosted pressurized fluid from the output port. The bypass unit includes a bypass flow path having one end connected to the fluid supply source side and the other end connected to the output port side. The bypass flow path is provided with a bypass check valve configured to block the flow of the pressurized fluid from the output port side to the fluid supply source side.

A pressure-booster output stabilizer includes: a first cylinder having therein a first chamber and a second chamber separated by a first piston; a second cylinder having therein a third chamber and a fourth chamber separated by a second piston; and a piston rod configured to couple the first piston and the second piston. The primary pressure of a pressure booster is supplied to the first chamber, the secondary pressure of the pressure booster is supplied to the fourth chamber, and the pressurized fluid is taken out from the fourth chamber.

A pressure-booster output stabilizer includes: a first cylinder having therein a first chamber and a second chamber separated by a first piston; a second cylinder having therein a third chamber and a fourth chamber separated by a second piston; and a piston rod configured to couple the first piston and the second piston. The primary pressure of a pressure booster is supplied to the first chamber, the secondary pressure of the pressure booster is supplied to the fourth chamber, and the pressurized fluid is taken out from the fourth chamber.

This invention is a portable pneumatically driven pressure intensifying positive displacement hydraulic power unit that can be transported in a bag or backpack and carried or worn by the user. The device can be powered by any suitable high pressure gas that is preferably contained in a small pressure vessel for portability. The device can be used to supply high pressure hydraulic fluid to tools with a wide range of uses in many fields including construction, industrial, breaching, and emergency service situations. This novel device does not require an electric or fuel powered hydraulic fluid pumping system, which allows it to be very portable and used in almost any environment (e.g., hazardous atmosphere or under water) without being tethered to an electric or fuel powered power source.

A pressure intensifier device increases pressure in a pressurized fluid chamber of a piston/cylinder unit. The pressure intensifier device has a pressure intensifier cylinder and a pressure intensifier piston, which is guided in an axially movable manner in the cylinder, wherein the pressure intensifier cylinder has an outlet region, an inlet region upstream of the outlet region and a piston guiding chamber, and the pressure intensifier piston has a piston part, which is guided in the piston guiding chamber, and a piston rod, which extends from the piston part to the inlet region, in a maximally retracted release position releases a fluid connection between the inlet region and the outlet region and, in a maximally advanced blocking position, blocks this connection with a free end portion, with which it extends into the outlet region. Over a portion that can be passed through by the free end portion of the piston rod during movement from the release position into the blocking position, the outlet region has a free passage cross section for the free piston rod end portion that is at least equal in size to a rod cross section of the free piston rod end portion. A pressure intensifier inlet valve can be controlled independently of a pressure in the pressurized fluid chamber of the piston/cylinder unit.

A pressure intensifier device increases pressure in a pressurized fluid chamber of a piston/cylinder unit. The pressure intensifier device has a pressure intensifier cylinder and a pressure intensifier piston, which is guided in an axially movable manner in the cylinder, wherein the pressure intensifier cylinder has an outlet region, an inlet region upstream of the outlet region and a piston guiding chamber, and the pressure intensifier piston has a piston part, which is guided in the piston guiding chamber, and a piston rod, which extends from the piston part to the inlet region, in a maximally retracted release position releases a fluid connection between the inlet region and the outlet region and, in a maximally advanced blocking position, blocks this connection with a free end portion, with which it extends into the outlet region. Over a portion that can be passed through by the free end portion of the piston rod during movement from the release position into the blocking position, the outlet region has a free passage cross section for the free piston rod end portion that is at least equal in size to a rod cross section of the free piston rod end portion. A pressure intensifier inlet valve can be controlled independently of a pressure in the pressurized fluid chamber of the piston/cylinder unit.

A dump trailer and a hydraulic cylinder assembly for the dump trailer are described herein. The cylinder assembly includes a first barrel, a second barrel rigidly coupled to the first barrel along a longitudinal axis of the cylinder assembly, and a piston assembly. The first barrel includes an inlet port for receiving vehicle hydraulic fluid and an outlet port for providing the vehicle hydraulic fluid to the vehicle. The second barrel includes an inlet port and an outlet port for providing dump trailer hydraulic fluid to a hydraulic lifting mechanism of the dump trailer. The piston assembly includes a first piston and a second piston coupled to the first piston by a shaft. The piston assembly is configured to provide the dump trailer hydraulic fluid to the hydraulic lifting mechanism to lift a box of the dump trailer when the cylinder assembly receives hydraulic fluid from the vehicle.