A hydraulic pump is described, comprising at least one inlet duct for a fluid, at least one outlet duct for the fluid and at least one pumping unit interposed between the inlet and outlet ducts. At least one multifunction valve is interposed between the inlet duct, upstream of the pumping unit, and the outlet duct, downstream of the pumping unit, which valve is configured to divert the flow of fluid from the inlet duct to the outlet duct without the fluid flowing into the pumping unit. The multifunction valve comprises a valve body that defines an inner bypass channel in which a shutter element is axially movable, an actuator member operatively associated with the shutter element and configured to move it from a closing position to an opening position of the bypass channel, and an elastic contrast element operatively associated with the shutter element and configured to keep it in the first closing position of the bypass channel when such shutter element is not actuated by the actuator member. The actuator member consists of a bias spring manufactured with a shape memory alloy, configured to move the shutter element from the first closing position to the second opening position of the bypass channel when a predefined temperature value is reached.

A stacked gerotor pump is provided. The stacked gerotor pump includes a first gerotor pump defining a first inlet section and a first outlet section, a second gerotor pump defining a second inlet section and a second outlet section and a plate. The plate is interposed between the first and second gerotor pumps and defines upstream cavities respectively communicative with the first and second inlet sections, downstream cavities respectively communicative with the first and second outlet sections and a pre-pressurization hole by which the second outlet section is communicative with the first inlet section.

A priming pump may include a housing; an inlet passageway inside of the housing; an outlet passageway inside of the housing; a divider, inside of the housing, separating the inlet passageway and the outlet passageway; a connecting passageway through the divider in fluid communication with the inlet passageway and the outlet passageway; a valve, disposed in the connecting passageway, configured for one-way fluid flow from the inlet passageway to the outlet passageway; a rotary pump, inside of the housing, having an inlet in fluid communication with the inlet passageway and an outlet in fluid communication with the outlet passageway; and a shaft connected to the rotary pump and extending through the housing, the shaft configured for rotation by an external driving mechanism.

A device for pumping a viscous fluid includes two positive displacement rotary pumps, a first pump (1) and a second pump (2), wherein each pump has an inlet (3, 4) for fluid at a suction side and an outlet (5, 6) for fluid on a discharge side, wherein the inlet (3) of the first pump (1) is connected to a reservoir of the viscous fluid by a connection (14) pipe or hose, wherein the apparatus further includes an intermediate part or connection (7) having an inlet (8), a first outlet (9) and a flow path (10) for fluid, wherein the outlet (5) of the first pump is connected to the inlet (8) of the intermediate part and the outlet (9) of the intermediate part is connected to the inlet (4) of the second pump, such that during the pumping the viscous fluid is forced from the reservoir through the first pump (1), through the intermediate part (7) and through the second pump (2) to the outlet (6) of the second pump.

A device for pumping a viscous fluid includes two positive displacement rotary pumps, a first pump (1) and a second pump (2), wherein each pump has an inlet (3, 4) for fluid at a suction side and an outlet (5, 6) for fluid on a discharge side, wherein the inlet (3) of the first pump (1) is connected to a reservoir of the viscous fluid by a connection (14) pipe or hose, wherein the apparatus further includes an intermediate part or connection (7) having an inlet (8), a first outlet (9) and a flow path (10) for fluid, wherein the outlet (5) of the first pump is connected to the inlet (8) of the intermediate part and the outlet (9) of the intermediate part is connected to the inlet (4) of the second pump, such that during the pumping the viscous fluid is forced from the reservoir through the first pump (1), through the intermediate part (7) and through the second pump (2) to the outlet (6) of the second pump.

A pump device includes a rotating body, a pump housing including a suction port and a discharge port, and a relief valve. In the pump device, a fluid is sucked from the suction port and discharged from the discharge port by rotation of the rotating body. The relief valve includes a valve body and a biasing member. The discharge port includes an one end in a direction in which the discharge port extends. The one end is shallower than a middle portion of the discharge port. The pump housing includes a relief flow path through which the fluid flows when the relief valve opens. The relief flow path is provided so as to be open to a groove bottom surface of the one end of the discharge port.

A system (100) for testing an agricultural implement includes a frame (106) configured to receive a device (104) to be tested. The frame carries a filter (108), a pump (112), a pressure relief valve (116) in fluid communication with the pump outlet, a frame output tube (122) to deliver the flow of fluid from the pump outlet to the device to be tested, a frame return tube (124) to receive the flow of fluid from the device to be tested, and a recycle flow outlet (128). A method of testing includes connecting a device to the frame output tube and the frame return tube, pumping a fluid from the frame output tube to the frame return tube through the device, and measuring a flow rate of the fluid through the device.

A system (100) for testing an agricultural implement includes a frame (106) configured to receive a device (104) to be tested. The frame carries a filter (108), a pump (112), a pressure relief valve (116) in fluid communication with the pump outlet, a frame output tube (122) to deliver the flow of fluid from the pump outlet to the device to be tested, a frame return tube (124) to receive the flow of fluid from the device to be tested, and a recycle flow outlet (128). A method of testing includes connecting a device to the frame output tube and the frame return tube, pumping a fluid from the frame output tube to the frame return tube through the device, and measuring a flow rate of the fluid through the device.

A fluid transfer pump that has a housing, a body portion movable within the housing between a first position and a second position, a gear coupled to the housing, a body cavity defined partially between the body portion and the housing, and an aperture defined in the housing that selectively provides a fluid to the body cavity. When the fluid is applied to the body cavity at or above a pilot pressure, the body portion is in the first position adjacent to the gear and when the fluid is applied to the body cavity at a fluid pressure lower than the pilot pressure, the body portion is in the second position and spaced from the gear.

A fluid transfer pump that has a housing, a body portion movable within the housing between a first position and a second position, a gear coupled to the housing, a body cavity defined partially between the body portion and the housing, and an aperture defined in the housing that selectively provides a fluid to the body cavity. When the fluid is applied to the body cavity at or above a pilot pressure, the body portion is in the first position adjacent to the gear and when the fluid is applied to the body cavity at a fluid pressure lower than the pilot pressure, the body portion is in the second position and spaced from the gear.