Check valve and piston pump having check valve

A check valve for arranging between a first pressure chamber, in which a first pressure of a fluid prevails, and a second pressure chamber in which a second pressure prevails, comprising a valve housing on which a valve seat is formed, and comprising a blocking element which is designed in a blocking position to close a valve opening in the region of the valve seat, in order to block a connection between the first and the second valve chambers, when the second pressure is greater than the first pressure, and is designed in an open position to release the valve opening in order to release the connection between the first and the second valve chambers when the first pressure is greater than the second pressure, the fluid being able to flow in the open position in a flow direction from the first pressure chamber into the second pressure chamber,

• wherein the valve seat is configured as an oblique surface, which is aligned relative to the flow direction at an angle which is greater than 15° and less than 80°, the blocking element comprising a planar blocking lobe made from an elastically deformable material which in the blocking position bears against the oblique surface, and in the open position, due to the difference between the first pressure and the second pressure, lifts away from the oblique surface in order to release the connection, wherein the blocking element has an annular fastening portion, by means of which the blocking element is fastened to the valve housing, wherein the valve housing has an annular fastening recess, which is aligned transversely to the flow direction, the fastening portion being inserted into the fastening recess in order to secure the blocking element in the flow direction positively to the valve housing, and wherein the annular fastening portion comprising an annular portion, which is inserted into an annular fastening recess of the valve housing.