A mechanical transmission system that transmits motions and forces from one location to another while allowing the relative position/orientation of the two locations to change continuously is disclosed. The system can be used to actuate the joints and tooling of a robotic arm using stationary motors in the robot's base. Since the motors do not contribute any weight or inertia to the arm, this yields a lightweight and agile arm that is more human safe. The transmission includes a controller hydraulic cylinder connected to a remote cylinder by a tubing assembly, which contains hydraulic fluid, and a wire cable. The fluid transmits pushing forces between pistons of the cylinders, while the cable transmits pulling forces. The tubing assembly allows the cylinders to move in space relative to one another.

A hydraulic pump to synchronize the operation of a pair of hydraulic actuators wherein each hydraulic actuator comprises a cylinder including a first fluid port and a second fluid port formed in the proximal and distal end portions thereof respectively and having a piston disposed therein coupled to a piston rod at least partially disposed within the corresponding cylinder. The dual hydraulic pump includes a triple gear assembly to alternately feed pressurized hydraulic fluid to the first fluid port of each hydraulic actuator simultaneously or the second fluid port of each hydraulic actuator simultaneously to synchronize the linear movement of each piston and piston rod in a first direction or a second direction.

A hydraulic pump to synchronize the operation of a pair of hydraulic actuators wherein each hydraulic actuator comprises a cylinder including a first fluid port and a second fluid port formed in the proximal and distal end portions thereof respectively and having a piston disposed therein coupled to a piston rod at least partially disposed within the corresponding cylinder. The dual hydraulic pump includes a triple gear assembly to alternately feed pressurized hydraulic fluid to the first fluid port of each hydraulic actuator simultaneously or the second fluid port of each hydraulic actuator simultaneously to synchronize the linear movement of each piston and piston rod in a first direction or a second direction.

When a fluid is supplied to a first pressure-boosting chamber and/or a second pressure-boosting chamber of a pressure booster, either a first electromagnetic valve unit supplies a fluid discharged from a first pressurizing chamber to a second pressurizing chamber, or a second electromagnetic valve unit supplies a fluid discharged from a third pressurizing chamber to a fourth pressurizing chamber.

When a fluid is supplied to a first pressure-boosting chamber and/or a second pressure-boosting chamber of a pressure booster, either a first electromagnetic valve unit supplies a fluid discharged from a first pressurizing chamber to a second pressurizing chamber, or a second electromagnetic valve unit supplies a fluid discharged from a third pressurizing chamber to a fourth pressurizing chamber.

By setting an outer circumferential surface of a second hydraulic chamber of a cylinder device to be a thin portion, hydraulic pressure increases by receiving air pressure from the second pneumatic chamber, and the thin portion expands to clamp a cylinder. Then, by the increase of the second hydraulic chamber, expansion of the thin portion in an axial direction is suppressed and the thin portion expands in a radial direction, and thus, as means for suppressing expansion in the axial direction, the thin portion is fixed from both end sides thereof with an expansion stop bolt. The expansion stop bolt fixes a lid and a lid disposed so as to sandwich pressed portions on both end sides of the thin portion or both ends of the thin portion. Further, in order to prevent the thin portion from being shrunk by tightening with the expansion stop bolt, a spacer is disposed between the pressed portions on both end sides of the thin portion.

By setting an outer circumferential surface of a second hydraulic chamber of a cylinder device to be a thin portion, hydraulic pressure increases by receiving air pressure from the second pneumatic chamber, and the thin portion expands to clamp a cylinder. Then, by the increase of the second hydraulic chamber, expansion of the thin portion in an axial direction is suppressed and the thin portion expands in a radial direction, and thus, as means for suppressing expansion in the axial direction, the thin portion is fixed from both end sides thereof with an expansion stop bolt. The expansion stop bolt fixes a lid and a lid disposed so as to sandwich pressed portions on both end sides of the thin portion or both ends of the thin portion. Further, in order to prevent the thin portion from being shrunk by tightening with the expansion stop bolt, a spacer is disposed between the pressed portions on both end sides of the thin portion.

When a fluid is supplied to a first pressure-boosting chamber and/or a second pressure-boosting chamber of a pressure booster, either a first electromagnetic valve unit supplies a fluid discharged from a first pressurizing chamber to a second pressurizing chamber, or a second electromagnetic valve unit supplies a fluid discharged from a third pressurizing chamber to a fourth pressurizing chamber.

A pump-regulator combination includes first and second pumps, a control valve, first orifice, and pilot valve. The first pump is configured to pump fluid from a tank to a first point. The control valve is configured to control pressure and/or delivery flow at the first point by adjusting a displacement volume of the first pump. The second pump is configured to pump fluid from the tank to a second point, through the first orifice, and back to the tank. A highest load pressure of the actuator is connected to a third point. The pilot valve includes an adjustable second orifice connected to the third point, via a fourth point, and the tank to pass fluid from the actuator to the tank. A pressure at the second point acts to close the second orifice. A pressure of the fourth point acts to adjust the control valve.

A pump-regulator combination includes first and second pumps, a control valve, first orifice, and pilot valve. The first pump is configured to pump fluid from a tank to a first point. The control valve is configured to control pressure and/or delivery flow at the first point by adjusting a displacement volume of the first pump. The second pump is configured to pump fluid from the tank to a second point, through the first orifice, and back to the tank. A highest load pressure of the actuator is connected to a third point. The pilot valve includes an adjustable second orifice connected to the third point, via a fourth point, and the tank to pass fluid from the actuator to the tank. A pressure at the second point acts to close the second orifice. A pressure of the fourth point acts to adjust the control valve.