A pump device for a brake system of a motor vehicle has a housing, a pressure piston which delimits a pressure chamber in the housing for producing hydraulic pressure mounted in the housing in a longitudinally displaceable manner, a return spring assigned to the pressure piston, a non-return valve which separates the pressure chamber from a pressure connection and only removes the separation when the hydraulic pressure in the pressure chamber is greater than in the pressure connection, and an electromagnetic actuator which includes an armature and an electrically energizable solenoid. The armature is arranged on the pressure piston and the solenoid in and/or on the housing. The pressure piston has an axial through-channel which opens out into the pressure chamber at one end and is assigned to the non-return valve at the other end.

A pump arrangement for pumping a liquid, in particular a liquid contaminated with dirt particles, the pump arrangement having at least one working chamber (1, 2, 11, 12) and at least one delivery piston (3, 4, 13), and at least one inlet valve (7) and at least one outlet valve (8), and the delivery piston (3, 4, 13) being movable in order to suck liquid into the working chamber (1, 2, 11, 12) through the inlet valve (7) and to eject liquid out of the working chamber (1, 2, 11, 12) through the outlet valve (8), and the pump arrangement having a wear-monitoring device (40) for monitoring the wear on the inlet valve (7) and/or outlet valve (8) with at least one pressure sensor (41) and one pressure evaluation unit (42) for processing pressure measurement values output from the pressure sensor (41), wherein the pump arrangement, for the purpose of moving the delivery piston (3, 4, 13), has a drive fluid system (20) that can be operated with a drive fluid, and the pressure sensor (41) of the wear-monitoring device (40) is arranged to detect the pressure of the drive fluid in the drive fluid system (20).

A pump for spraying liquid according to one aspect of the invention can include a housing having an interior space for holding a content; a guide that moves up and down within the interior space and has an inlet hole connecting with the interior space; a piston that moves with the guide while maintaining contact with the housing and the guide and is capable of closing the inlet hole; a valve coupled to and connecting with the guide and protruding to the exterior of the housing; a shoulder coupled to an upper portion of the housing; and an elastic member having one end contacting the shoulder and the other end contacting the valve to provide an elastic force pushing the valve upward, where the elastic member can include a center portion and deformation portions formed as an integrated body such that the elastic member is capable of elastic deformation.

An air driven reciprocating piston hydraulic pump having a main changeover valve with a main valve body having an annular valve body portion which includes first and second annular valve faces that approach closely or contact first and second annular valve seats on valve cases which are formed on the upper and the lower ends of the annular valve body portion. An air intake chamber is defined by a piston reception hole and a drive piston portion, and an auxiliary changeover valve changes over the main changeover valve between its air supply position and its air discharge position by supplying compressed air to the air intake chamber or discharging air therefrom via a first and second valve members and a small diameter portion of a valve rod. A center side portion of the main valve body is made as a separate auxiliary valve body for facilitating up and down motion thereof.

In a piston pump, for example, a piston sub assembly includes a columnar plunger that lies along an axial direction, a cap that is fixed with the plunger to cover an adjacent region between a first end surface at one end in the axial direction of the plunger and the first end surface at a first outer circumferential surface of the plunger, and provided with an intake passage extending from an inlet on an outer side of the first outer circumferential surface to an outlet on an outer side of the first end surface outside the plunger, and a first valve seat of a first intake check valve located at the outlet, and a seal member that is a member different from the cap and that prevents leakage of hydraulic fluid from the first chamber through a gap between the first cylinder and the piston sub assembly.

A system for dispensing abrasive materials includes a transfer pump configured to pump abrasive material to a metering pump configured to pump the abrasive material to an application. Dynamic interfaces within the pumps are at least partially formed by sleeved components of the pump interfacing with a seal configured to engage with the sleeved surface during relative movement between the sleeved surface and the seal. The smooth exterior surfaces of the sleeves interface with the seals to prevent abrasive particulate in the material from adhering to the sleeve, preventing the abrasive particulate from being pulled between the sleeve and the seal.

A pump for spraying liquid includes a housing having an interior space holding liquid, a guide moving up and down within the interior space and having an inlet hole connecting with the interior space, and a piston moving with the guide while maintaining a contact with the housing and the guide. The pump further includes a valve coupled to and connecting with the guide, a shoulder coupled to an upper portion of the housing, and an elastic member having one end in contact with the shoulder and the other end in contact with the valve to provide an elastic force pushing the valve upward. The elastic member includes a center portion and upper and lower deformation portions which are formed as an integrated body.

In a piston pump, for example, a piston sub assembly includes a columnar plunger that lies along an axial direction, a cap that is fixed with the plunger to cover an adjacent region between a first end surface at one end in the axial direction of the plunger and the first end surface at a first outer circumferential surface of the plunger, and provided with an intake passage extending from an inlet on an outer side of the first outer circumferential surface to an outlet on an outer side of the first end surface outside the plunger, and a first valve seat of a first intake check valve located at the outlet, and a seal member that is a member different from the cap and that prevents leakage of hydraulic fluid from the first chamber through a gap between the first cylinder and the piston sub assembly.

A piston for a single-stroke pump includes a pump rod, a seal ring extending about the pump rod and having a central bore, and a retaining device disposed on the pump rod and retaining the seal ring on the pump rod. In a forward stroke, the seal ring is in a first position whereby the seal ring sealingly engages the pump rod such that the seal ring and pump rod drive a fluid out of the pump chamber. When transitioning to a return stroke, the seal ring is maintained stationary relative to the pump cylinder until retaining device engages seal ring, such that seal ring is in a second position. With the seal ring in the second position, a flow path is opened between the seal ring and the pump rod, allowing fluid to flow into the pump chamber to prime the pump the next pump cycle.

A pump device for a brake system of a motor vehicle has a housing, a pressure piston which delimits a pressure chamber in the housing for producing hydraulic pressure mounted in the housing in a longitudinally displaceable manner, a return spring assigned to the pressure piston, a non-return valve which separates the pressure chamber from a pressure connection and only removes the separation when the hydraulic pressure in the pressure chamber is greater than in the pressure connection, and an electromagnetic actuator which includes an armature and an electrically energizable solenoid. The armature is arranged on the pressure piston and the solenoid in and/or on the housing. The pressure piston has an axial through-channel which opens out into the pressure chamber at one end and is assigned to the non-return valve at the other end.