Coupling device

A coupling device for coupling together a tool holder (3) with a rotatable spindle (2) of a machining machine, which coupling device (4) comprises:

• a female-shaped coupling part (10) and a corresponding male-shaped coupling part (20), the female-shaped coupling part (10) being fixedly connected to the spindle (2) and being provided with an internally cone-shaped section (11), whereas the male-shaped coupling part (20) is fixedly connected to the tool holder (3) and is provided with an externally cone-shaped section (21) which is configured for engagement with said internally cone-shaped section (11);
• an annular groove (25) arranged in the externally cone-shaped section (21), this groove (25) extending in one turn around this section (21);
• at least two locking balls (15), which are received in a respective radial through hole (16) in said internally cone-shaped section (11) while being radially displaceable in this hole, these holes (16) being distributed in the circumferential direction of this section (11) and arranged to be aligned with the groove (25) in the externally cone-shaped section (21) when the male-shaped coupling part (20) is inserted in the female-shaped coupling part (10) with the cone-shaped sections (11, 21) in engagement with each other;
• and
• a locking sleeve (30) which is rotatably arranged on the outside of the female-shaped coupling part (10) outwardly of the internally cone-shaped section (11) and the locking balls (15), the locking sleeve (30) being rotatable to and fro between a releasing position, in which the locking sleeve (30) allows the respective locking ball (15) to be displace radially to a retracted position while allowing a mutual axial displacement between said coupling parts (10, 20), and a locking position, in which the locking sleeve (30) forces the respective locking ball (15) to assume an advanced position with the locking ball (15) extending through the inwards facing opening of the associated hole (16) and down into the groove (25) in the externally cone-shaped section (21) while preventing a mutual axial displacement between said coupling parts (10, 20), wherein
• the locking sleeve (30) is provided with at least two radially springing guide members (31),
• the respective guide member (31) co-operates with one of said locking balls (15) and is arranged to be rotated together with the locking sleeve (30) and be pressed against the associated locking ball (15) to lock this locking ball (15) in said advanced position when the locking sleeve (30) is rotated from said releasing position to said locking position,
• the respective guide member (31) is provided with an internal guide cam (32), along which the associated locking ball (15) is displaced in connection with a rotation of the locking sleeve (30) between said releasing position and said locking position, this guide cam (32) being at one of its ends provided with a recess (33), in which the associated locking ball (15) is arranged to be received when the locking sleeve (30) is in said locking position to thereby retain the locking sleeve in the locking position,
• the locking sleeve (30) comprises a ring-shaped holder (34), which extends around the female-shaped coupling part (10) and via which the locking sleeve (30) slidably bears against an envelope surface (18) of the female-shaped coupling part (10), the guide members (31) being springingly fixed to this ring-shaped holder (34),
• the respective guide member (31) at one of its ends is fixed to the ring-shaped holder (34) via an axially extending connecting section (35), and
• the recess (33) being provided at an end of the internal guide cam (32) of the respective guide member (31) remote from the axially extending connecting section (35).

A coupling device for coupling together a tool holder (3) with a rotatable spindle (2) of a machining machine, which coupling device (4) comprises:

• a female-shaped coupling part (10) and a corresponding male-shaped coupling part (20), the female-shaped coupling part (10) being fixedly connected to the spindle (2) and being provided with an internally cone-shaped section (11), whereas the male-shaped coupling part (20) is fixedly connected to the tool holder (3) and is provided with an externally cone-shaped section (21) which is configured for engagement with said internally cone-shaped section (11);
• an annular groove (25) arranged in the externally cone-shaped section (21), this groove (25) extending in one turn around this section (21);
• at least two locking balls (15), which are received in a respective radial through hole (16) in said internally cone-shaped section (11) while being radially displaceable in this hole, these holes (16) being distributed in the circumferential direction of this section (11) and arranged to be aligned with the groove (25) in the externally cone-shaped section (21) when the male-shaped coupling part (20) is inserted in the female-shaped coupling part (10) with the cone-shaped sections (11, 21) in engagement with each other;
• and
• a locking sleeve (30) which is rotatably arranged on the outside of the female-shaped coupling part (10) outwardly of the internally cone-shaped section (11) and the locking balls (15), the locking sleeve (30) being rotatable to and fro between a releasing position, in which the locking sleeve (30) allows the respective locking ball (15) to be displace radially to a retracted position while allowing a mutual axial displacement between said coupling parts (10, 20), and a locking position, in which the locking sleeve (30) forces the respective locking ball (15) to assume an advanced position with the locking ball (15) extending through the inwards facing opening of the associated hole (16) and down into the groove (25) in the externally cone-shaped section (21) while preventing a mutual axial displacement between said coupling parts (10, 20), wherein
• the locking sleeve (30) is provided with at least two radially springing guide members (31),
• the respective guide member (31) co-operates with one of said locking balls (15) and is arranged to be rotated together with the locking sleeve (30) and be pressed against the associated locking ball (15) to lock this locking ball (15) in said advanced position when the locking sleeve (30) is rotated from said releasing position to said locking position,
• the locking sleeve (30) comprises an external protective casing (36) which surrounds the ring-shaped holder (34) and the guide members (31), and
• the respective guide member (31) is provided with an internal guide cam (32), along which the associated locking ball (15) is displaced in connection with a rotation of the locking sleeve (30) between said releasing position and said locking position, this guide cam (32) being at one of its ends provided with a recess (33), in which the associated locking ball (15) is arranged to be received when the locking sleeve (30) is in said locking position to thereby retain the locking sleeve in the locking position.