A clamping device for releasably holding a tool holder shank, the clamping device comprising:
- a housing having a front end, a rear end and a bore which intersects the front end and extends rearwardly therefrom, wherein a mounting portion for receiving the tool holder shank is provided at a front end of the bore;
- a drawbar slidably mounted inside the bore so as to be reciprocally moveable in the bore along a longitudinal axis thereof between an advanced releasing position and a retracted locking position;
- engagement members arranged around the drawbar at a front end thereof, wherein the engagement members, under the effect of a movement of the drawbar from the advanced releasing position to the retracted locking position, are moveable from a first position, in which the engagement members allow the tool holder shank to move into and out of said mounting portion, to a second position, in which the engagement members are in locking engagement with the tool holder shank and keep it secured to the housing;
- and
- a first wedge having a wedge surface facing towards the rear end of the housing and a first pressure receiving surface, wherein the first wedge is slidably received in a first aperture that extends radially through a peripheral wall of the housing, wherein the first pressure receiving surface on the first wedge faces outwards from the housing and the wedge surface on the first wedge is in contact with a first slide surface on the drawbar facing towards the front end of the housing, the first wedge being configured to press the drawbar towards the retracted locking position when it is pressed radially inwards in the first aperture;
- that, the clamping device including a second wedge slidably received in a second aperture that extends radially through the peripheral wall, wherein the second wedge includes a second wedge surface, which faces towards the front end of the housing and is in contact with a second slide surface on the drawbar facing towards the rear end of the housing, and a second pressure receiving surface, which faces outwards from the housing, the second wedge being configured to press the drawbar towards the advanced releasing position when it is pressed radially inwards in the second aperture, wherein the clamping device includes an actuating sleeve arranged around the peripheral wall and slidably mounted to it so as to be axially moveable in relation to the housing in a first axial direction in order to effect a movement of the drawbar from the advanced releasing position to the retracted locking position and in an opposite second axial direction in order to effect a movement of the drawbar from the retracted locking position to the advanced releasing position, wherein the actuating sleeve on its inner side is provided with a first pressure applying surface, which faces inwards for contacting the first pressure receiving surface and has a radial distance to the longitudinal axis that increases as seen in said first axial direction, and a second pressure applying surface, which faces inwards for contacting the second pressure receiving surface and has a radial distance to the longitudinal axis that increases as seen in said second axial direction, wherein the first pressure applying surface is configured to press the first wedge radially inwards in the first aperture by pressing against the first pressure receiving surface when the actuating sleeve is moved in said first axial direction, and wherein the second pressure applying surface is configured to press the second wedge radially inwards in the second aperture by pressing against the second pressure receiving surface when the actuating sleeve is moved in said second axial direction.