Mechanism for grasping tool, chuck, clamp mechanism, or the like

A double draw bar structure comprising:

• an outer draw bar and an inner draw bar, wherein
• a portion of the outer draw bar near an end thereof on a front side is formed as a circular cylindrical part, while the circular cylindrical part has a plurality of ball holes therein,
• in the outer draw bar, a front sloped surface is provided on a front and outer side of each of the plurality of ball holes, while an inner large-diameter part is provided on a rear and inner side of the ball holes, and further, an inner small-diameter part is provided on a rear side of the inner large-diameter part, and
• a portion of the inner draw bar near an end thereof on the front side is formed as a circular cylindrical part, while the circular cylindrical part has a plurality of ball holes therein, and an inner head space is provided on a rear side of the plurality of ball holes, and upon inserting the inner draw bar into the outer draw bar, the ball holes provided in the inner draw bar are configured so as to be movable from an inside of the inner large-diameter part to an inside of the inner small-diameter part.

A spindle to which it is possible to attach any of a tool holder, a chuck holder, and a clamp holder, the spindle comprising:

• a spindle case, a bearing attached to the spindle case, a shaft rotatably held by the bearing, and an outer draw bar and an inner draw bar inserted in a bore in the shaft, wherein
• the bore in the shaft is provided with an outer large-diameter part and an outer small-diameter part,
• a portion of the outer draw bar near an end thereof on a front side is formed as a circular cylindrical part, while the circular cylindrical part has a plurality of ball holes therein so that outer balls are provided while being held so as to be movable in a normal line direction, and an outer head space is provided on a rear side of the outer balls, while an inner large-diameter part is provided on a rear side of the outer head space, whereas an inner small-diameter part is provided on a rear side of the inner large-diameter part,
• a portion of the inner draw bar near an end thereof on the front side is formed as a circular cylindrical part, while the circular cylindrical part has a plurality of ball holes therein so that inner balls are provided while being held so as to be movable in a normal line direction, and an inner head space is provided on a rear side of the inner balls, whereas the inner draw bar is inserted into the outer draw bar, and
• a double gripping mechanism is formed by an outer gripping mechanism and an inner gripping mechanism, the outer gripping mechanism including the outer large-diameter part, the outer small-diameter part, the outer draw bar, and the outer balls, and the inner gripping mechanism including the inner large-diameter part, the inner small-diameter part, the inner draw bar, and the inner balls.

A spindle to which it is possible to attach any of a tool holder, a chuck holder, and a clamp holder, the spindle comprising:

• a spindle case, a bearing attached to the spindle case, a shaft rotatably held by the bearing, and an outer draw bar and an inner draw bar inserted in a bore in the shaft, wherein
• a fixed guide having a plurality of guide holes therein is provided in the bore in the shaft, and a portion of the outer draw bar near an end thereof on a front side is formed as a circular cylindrical part, while the circular cylindrical part has a plurality of ball holes therein, and further, each of the outer balls is disposed so as to be stored in both one of the ball holes provided in the outer draw bar and one of the guide holes at a same time, and the outer balls are held so as to be movable in a normal line direction,
• in the outer draw bar, a front sloped surface is provided on a front and outer side of each of the plurality of ball holes, while an inner large-diameter part is provided on a rear and inner side of the ball holes, and further, an inner small-diameter part is provided on a rear side of the inner large-diameter part,
• a portion of the inner draw bar near an end thereof on the front side is formed as a circular cylindrical part, while the circular cylindrical part has a plurality of ball holes therein so that inner balls are provided while being held so as to be movable in a normal line direction, and an inner head space is provided on a rear side of the inner balls, whereas the inner draw bar is inserted into the outer draw bar, and
• a double gripping mechanism is formed by an outer gripping mechanism and an inner gripping mechanism, the outer gripping mechanism including the fixed guide, the outer draw bar, and the outer balls, and the inner gripping mechanism including the inner large-diameter part, the inner small-diameter part, the inner draw bar, and the inner balls.

A holder holding mechanism to which it is possible to attach any of a tool holder, a chuck holder, and a clamp holder, the holder holding mechanism comprising:

• a holding base;
• and an outer draw bar and an inner draw bar inserted in a bore in the holding base, wherein
• the bore in the holding base is provided with an outer large-diameter and an outer small-diameter part,
• a portion of the outer draw bar near an end thereof on a front side is formed as a circular cylindrical part, while the circular cylindrical part has a plurality of ball holes therein so that outer balls are provided while being held so as to be movable in a normal line direction, and an outer head space is provided on a rear side of the outer balls, while an inner large-diameter part is provided on a rear side of the outer head space, whereas an inner small-diameter part is provided on a rear side of the inner large-diameter part,
• a portion of the inner draw bar near an end thereof on the front side is formed as a circular cylindrical part, while the circular cylindrical part has a plurality of ball holes therein so that inner balls are provided while being held so as to be movable in a normal line direction, and an inner head space is provided on a rear side of the inner balls, whereas the inner draw bar is inserted into the outer draw bar, and
• a double gripping mechanism is formed by an outer gripping mechanism and an inner gripping mechanism, the outer gripping mechanism including the outer large-diameter part, the outer small-diameter part, the outer draw bar, and the outer balls, and the inner gripping mechanism including the inner large-diameter part, the inner small-diameter part, the inner draw bar, and the inner balls.

A holder holding mechanism to which it is possible to attach any of a tool holder, a chuck holder, and a clamp holder, the holder holding mechanism comprising:

• a holding base;
• and an outer draw bar and an inner draw bar inserted in a bore in the holding base, wherein
• a fixed guide having a plurality of guide holes therein is provided in the bore in the holding base, and a portion of the outer draw bar near an end thereof on a front side is formed as a circular cylindrical part, while the circular cylindrical part has a plurality of ball holes therein, and further, each of the outer balls is disposed so as to be stored in both one of the ball holes provided in the outer draw bar and one of the guide holes at a same time, and the outer balls are held so as to be movable in a normal line direction,
• in the outer draw bar, a front sloped surface is provided on a front and outer side of each of the plurality of ball holes, while an inner large-diameter part is provided on a rear and inner side of the ball holes, and further, an inner small-diameter part is provided on a rear side of the inner large-diameter part,
• a portion of the inner draw bar near an end thereof on the front side is formed as a circular cylindrical part, while the circular cylindrical part has a plurality of ball holes therein so that inner balls are provided while being held so as to be movable in a normal line direction, and an inner head space is provided on a rear side of the inner balls, whereas the inner draw bar is inserted into the outer draw bar, and
• a double gripping mechanism is formed by an outer gripping mechanism and an inner gripping mechanism, the outer gripping mechanism including the fixed guide, the outer draw bar, and the outer balls, and the inner gripping mechanism including the inner large-diameter part, the inner small-diameter part, the inner draw bar, and the inner balls.

A tool holder comprising:

• a holder base and an outer grasped part, wherein
• the holder base is able to hold a tool,
• the outer grasped part is configured with an outer pull stud including an outer head and an outer neck, and
• the outer pull stud has a hole through which an inner pull stud serving as an inner grasped part can penetrate.

A tool holder comprising:

• a holder base and an outer grasped part, wherein
• the holder base is able to hold a tool,
• the outer grasped part is formed as a substantially circular cylindrical part that has a grasped groove formed on an inner surface thereof, and
• a rear sloped surface is provided on a rear side of the grasped groove.

A chuck holder comprising:

• a holder base, an outer grasped part, and an inner grasped part, wherein
• the holder base is able to have a chuck attached thereto,
• the outer grasped part is configured with an outer pull stud including an outer head and an outer neck, whereas the inner grasped part is configured with an inner pull stud including an inner head and an inner neck, and
• the inner pull stud is attached so as to penetrate through holes provided in the outer pull stud and in the holder base so that the inner pull stud is connectable to a jaw slide of the chuck.

A chuck holder comprising:

• a holder base, an outer grasped part, and an inner grasped part, wherein
• the holder base is able to have a chuck attached thereto,
• the outer grasped part is formed as a substantially circular cylindrical part that has a grasped groove formed on an inner surface thereof, whereas the inner grasped part is configured with an inner pull stud including an inner head and an inner neck, and
• a rear sloped surface is provided on a rear side of the grasped groove in the substantially circular cylindrical part, and the inner pull stud is attached so as to penetrate through holes provided in the substantially circular cylindrical part and in the holder base so that the inner pull stud is connectable to a jaw slide of the chuck.

A clamp holder comprising:

• a holder base, an outer grasped part, and an inner grasped part, wherein
• the holder base is able to have a clamp mechanism attached thereto,
• the outer grasped part is configured with an outer pull stud including an outer head and an outer neck, whereas the inner grasped part is configured with an inner pull stud including an inner head and an inner neck, and
• the inner pull stud is attached so as to penetrate through holes provided in the outer pull stud and in the holder base so that the inner pull stud is connectable to a slide of the clamp mechanism.

A clamp holder comprising:

• a holder base, an outer grasped part, and an inner grasped part, wherein
• the holder base is able to have a clamp mechanism attached thereto,
• the outer grasped part is formed as a substantially circular cylindrical part that has a grasped groove formed on an inner surface thereof, whereas the inner grasped part is configured with an inner pull stud including an inner head and an inner neck, and
• a rear sloped surface is provided on a rear side of the grasped groove in the substantially circular cylindrical part, and the inner pull stud is attached so as to penetrate through holes provided in the substantially circular cylindrical part and in the holder base so that the inner pull stud is connectable to a slide of the clamp mechanism.