| 摘要 |
A chuck locking device for machine tools includes an axially mobile member (1) slidable within an axially stationary member (2), as well as an expander (3) axially slidable within the mobile member (1) and suitable to push three balls (4) radially outwards against a distal abutment surface (5) of the stationary member (2) through proper apertures (6) formed in the mobile member (1). The balls (4) roll along races, formed on the external surface of the expander (3), that have a decreasing slope from their proximal end towards their distal end up to the point of contact with the balls (4) which corresponds to the minimum working position of the device, and in the terminal distal length (16) of the races beyond said point of contact the slope increases up to their distal end so as to obtain a closed profile of the expander (3) suitable to prevent the balls (4) from leaving through its distal end. |
