In many pump types, in particular in orbital pumps, there is an optimization need with regard to the running characteristics, in particular with regard to parameters which relate to the delivery flow. What is provided is an orbital pump device for delivering liquid medium by a rotational movement including a hydraulic housing surrounding a hydraulic chamber in a fluid-tight manner at least one membrane unit which is arranged inside the hydraulic chamber in flat contact with an inner jacket surface of the hydraulic housing; and an inlet and an outlet provided in the hydraulic housing. At least one crowning is provided at the inner jacket surface and/or at the membrane unit such that a radial gap between the membrane unit and the inner jacket surface is defined by the crowning in a circumferential section of less than 360, and in particular less than 180.

An oil pump includes a rotation shaft, a pump unit including an inner rotor and an outer rotor, and a casing provided with a pump chamber accommodating the pump unit, wherein at least one of a first suction passage, a first ejection passage, a second suction passage, and a second ejection passage of the casing includes a check valve provided in the oil carrying passage and the check valve includes a ball and a seating portion allowing the ball to be seated thereon and does not use a spring.

An impeller is attached to a rotary shaft provided in an inner space of a housing and includes a tube fixed to the rotary shaft and a plurality of blades protruding toward an outer diameter direction from the tube. A tip of each blade is in slidable contact with an inner peripheral surface of the housing. Each blade has a shape curved toward a rotation-direction rear side of the rotary shaft in a free state and includes an extension surface on a rotation-direction front side of the rotary shaft and a compression surface on the rotation-direction rear side of the rotary shaft. A curvature radius of a root on the compression surface in the blade is formed larger than a curvature radius of a root on the extension surface in the blade.

An impeller is attached to a rotary shaft provided in an inner space of a housing and includes a tube fixed to the rotary shaft and a plurality of blades protruding toward an outer diameter direction from the tube. A tip of each blade is in slidable contact with an inner peripheral surface of the housing. Each blade has a shape curved toward a rotation-direction rear side of the rotary shaft in a free state and includes an extension surface on a rotation-direction front side of the rotary shaft and a compression surface on the rotation-direction rear side of the rotary shaft. A curvature radius of a root on the compression surface in the blade is formed larger than a curvature radius of a root on the extension surface in the blade.

A tube pump includes a base, a columnar inner peripheral surface, a tube disposed along the inner peripheral surface, a rotor disposed concentrically with the inner peripheral surface and supported by the base while squeezing the tube between the rotor and the inner peripheral surface, and a drive unit having a drive shaft passing through the base and configured to couple with the rotor, the base having a cylindrical supporting part configured to support the rotor and the drive shaft being inserted in a hollow portion of the supporting part, the tube pump including a bearing configured to rotatably support the rotor, the rotor having a body on which a coupling hole configured to accommodate the supporting part and the bearing is formed and an annular groove extending in a circumferential direction being formed on an inner peripheral surface of the body, the bearing fitting in the annular groove.

A tube pump includes a base, a columnar inner peripheral surface, a tube disposed along the inner peripheral surface, a rotor disposed concentrically with the inner peripheral surface and supported by the base while squeezing the tube between the rotor and the inner peripheral surface, and a drive unit having a drive shaft passing through the base and configured to couple with the rotor, the base having a cylindrical supporting part configured to support the rotor and the drive shaft being inserted in a hollow portion of the supporting part, the tube pump including a bearing configured to rotatably support the rotor, the rotor having a body on which a coupling hole configured to accommodate the supporting part and the bearing is formed and an annular groove extending in a circumferential direction being formed on an inner peripheral surface of the body, the bearing fitting in the annular groove.

A method for operating a device for dosed supply of a liquid, having a pump to deliver the liquid. The pump has an inlet and an outlet. An eccentric is arranged on the pump housing and a deformable diaphragm is arranged between a pump housing and the eccentric. The deformable diaphragm and the pump housing delimit a delivery path from the inlet to the outlet. The seal can be displaced along the delivery path by movement of the eccentric. A pressure sensor is connected to the outlet of the pump. A liquid is delivered by the pump. A time curve of the pressure at the outlet of the pump is monitored during delivery by the at least one pressure sensor. An angle position of the eccentric of the pump is detected using at least one characteristic feature of the time curve at the outlet.

A method for operating a device for dosed supply of a liquid, having a pump to deliver the liquid. The pump has an inlet and an outlet. An eccentric is arranged on the pump housing and a deformable diaphragm is arranged between a pump housing and the eccentric. The deformable diaphragm and the pump housing delimit a delivery path from the inlet to the outlet. The seal can be displaced along the delivery path by movement of the eccentric. A pressure sensor is connected to the outlet of the pump. A liquid is delivered by the pump. A time curve of the pressure at the outlet of the pump is monitored during delivery by the at least one pressure sensor. An angle position of the eccentric of the pump is detected using at least one characteristic feature of the time curve at the outlet.

A pump includes a pump-head portion including a pump body and a magnet cup. The pump body defines an inlet and an outlet, and the pump body and the magnet cup together define a pump cavity. The pump includes a suction shoe situated on the pump body. The suction shoe includes an engaging portion. The pump includes a movable pumping member situated in the pump cavity and at least partially received within the suction shoe. The pump includes a permanent magnet coupled to the pumping member. The pump includes a pump-driver portion including a magnet driver located outside the magnet cup. The pump includes a pressure-absorbing member situated in the pump cavity. The pressure-absorbing member is configured to engage the engaging portion of the suction shoe such that the suction shoe is urged radially inwardly with respect to an outer edge portion of the surface of the pump body.

A pump includes a pump-head portion including a pump body and a magnet cup. The pump body defines an inlet and an outlet, and the pump body and the magnet cup together define a pump cavity. The pump includes a suction shoe situated on the pump body. The suction shoe includes an engaging portion. The pump includes a movable pumping member situated in the pump cavity and at least partially received within the suction shoe. The pump includes a permanent magnet coupled to the pumping member. The pump includes a pump-driver portion including a magnet driver located outside the magnet cup. The pump includes a pressure-absorbing member situated in the pump cavity. The pressure-absorbing member is configured to engage the engaging portion of the suction shoe such that the suction shoe is urged radially inwardly with respect to an outer edge portion of the surface of the pump body.