A pump for conveying a fluid includes a pump housing, an eccentric, a deformable element arranged in a pump gap between the inner circumferential surface of the pump housing, and an outer surface of the eccentric, such that a conveying channel is formed from an inlet to an outlet. A stationary seal is provided between the outlet and the inlet and prevents a backflow of the fluid from the outlet back to the inlet. The inner circumferential surface of the pump housing has a recess in the region of the stationary seal, and the deformable element is tensioned fluid-tight at the inner circumference surface in the region of the recess using a pin.

A method for operating a device for providing a liquid additive having at least one suction point for removing liquid additive from a tank, a valve-free conveying line extending from the suction point to a supply unit, and a valve-free displacement pump, the displacement pump being configured to convey the liquid additive from the tank via the suction point along the conveying line to the supply unit, the displacement unit having at least one seal of the conveying line, displaceable along the conveying line for conveying the liquid additive, includes: a) detecting a stoppage of operation of the device; b) establishing a position of the seal within the positive-displacement pump; and c) changing the position of the seal if the position of the seal does not correspond to a provided park position of the seal.

The invention relates to a pump device (10) for pumping a fluid (13), comprising: a pump housing (12) having an annular portion (22); a pump ring (14), which is deformable and defines an annular pump chamber (57) at least in some portions; a first connection (51) and a second connection (52), said first connection (51) and said second connection (52) being in fluid communication with the pump chamber (57); an eccentric (18), which is designed to be rotatable relative to the pump housing (12) and which is arranged such in the pump device (10) that the eccentric (18), depending on a current rotational position of the eccentric (18), deforms the pump ring (14) in such a way that the pump ring (14) presses at least partially against the annular portion (22) in order to pump, by way of a rotation of the eccentric (18), the fluid (13) along the pump chamber (57) from the first connection (51) to the second connection (52) depending on the current rotational position of the eccentric; and a clamping element (114), which is designed to statically press the pump ring (14) against the annular portion (22) of the pump housing (12) in a clamping link region (45). The pump ring (14) has at least one recess (47) for accommodating at least part of the clamping element (114), said recess (47) being dimensioned such that in each rotational position of the eccentric (18) at least in some portions a distance (48) between the radially inner side (50) of the clamping element (114) and the pump ring (14) is provided.

Pump for conveying liquid, having at least one pump housing with at least one inlet and at least one outlet, and including an inner circumferential surface and a geometric axis, where an eccentric is arranged within the pump housing and is moveable eccentrically relative to the pump housing around the geometric axis. A deformable element is arranged in a pump gap between the inner circumferential surface of the pump housing and an outer surface of the eccentric. The deformable element is pressed against the pump housing by the outer surface of the eccentric along at least one section of a conveying channel such that at least one displaceable seal of the conveying channel and at least one closed pump volume are formed in the conveying channel which are displaceable by an eccentric movement of the eccentric for conveying the fluid along the conveying channel from the inlet to the outlet.

A pump for conveying a fluid includes a pump housing with an inlet, an outlet, an inner circumferential surface and a geometric axis. An eccentric is rotatable in the housing around the geometric axis. A deformable element is disposed in a pump gap between inner and outer surfaces of the eccentric. A conveying channel is formed from inlet to outlet by the deformable element and the inner circumferential surface. The deformable element is pressed in sections against the housing by the outer eccentric surface, forming a displaceable seal of the channel and a closed pump volume in the channel being displaceable by rotation of the eccentric for conveying the fluid along the channel from inlet to outlet. The deformable element has a protrusion on one or both sides towards the geometric axis extending over the outer eccentric surface and contacting the deformable element. A centering ring is inside the protrusion.

A pump for conveying liquid includes a pump housing with an inlet and an outlet. An eccentric mounted at the housing rotates about an axis relative to the housing. A deformable element is disposed between the housing and the eccentric. A delivery duct from the inlet to the outlet is formed by the deformable element and a circumferential housing surface. The deformable element is pressed in sections against the housing by the eccentric to form a displaceable seal of the delivery duct and a closed pump volume in the delivery duct, which can be displaced along the delivery duct from the inlet to the outlet by a movement of the eccentric to convey liquid. A channel cross-section of the delivery duct is limited by the circumferential surface, a set-back duct surface of the deformable element and a contact seal between the circumferential surface and the deformable element.

A pump includes a pump housing, an inlet, an outlet, a rotatable eccentric, a deformable element between housing and eccentric and a delivery channel from inlet to outlet formed by the deformable element and the housing. The deformable element is pressed against the housing in sections by the eccentric forming a movable seal of the channel and a closed volume in the channel being movable along the channel from inlet to outlet to pump the liquid by rotating the eccentric. A method for operating the pump includes a) setting a liquid quantity to be pumped, b) determining a temperature of the deformable element, c) determining a parameter considering the temperature from step b), the parameter representing a dependence between movement of the eccentric and pump capacity and d) pumping the liquid quantity set in step a) by adapting an operating mode of the pump considering the parameter from step c).

A pump for conveying liquid includes a pump housing having an inlet, an outlet, an inner circumferential surface and a geometric axis. An eccentric in the housing is rotatable about the geometric axis relative to the housing. A deformable element is disposed between the inner circumferential housing surface and the eccentric. A delivery duct from the inlet to the outlet is formed by the deformable element and the inner circumferential housing surface. The deformable element is pressed against the housing by the eccentric in sections so that a displaceable seal of the duct and a closed pump volume in the duct are formed and are displaceable to convey the liquid along the duct from the inlet to the outlet by rotation of the eccentric. A receptacle, accommodating an edge region of the deformable element, is formed by the inner circumferential housing surface and a counter bracket.