Hydraulic tool mount and sealing piston for such a mount

A sealing piston for a hydraulic tool mount, comprising a pin, a seal and a head which are arranged one behind the other in an axial direction (A) and thus form a stack, wherein the seal comprises a circumferential sealing lip for abutment and sealing against an inner wall of a bore of the hydraulic tool mount in order to achieve a first sealing effect, wherein the bore comprises an outer section in which the sealing piston is seated and an inner section that is tapered relative to the outer section, and thus has a diameter (d1) that is smaller than a diameter (d2) of the head, wherein the head is stopped by and abuts a sealing seat of the bore of the hydraulic tool mount, thereby closing an opening of the inner section of the bore in order to achieve a second sealing effect,

• wherein the head comprises a plate and a ball,
• wherein the plate is disposed between the seal and the ball such that the ball is pressed into the sealing seat when in an end position.