Abstract: A tool holder includes a holder body, a tapered collet, a first side lock bolt, a second side lock bolt, and a key. The key fits in a keyway of the collet, contacts the inner peripheral surface of a front hole, and contacts a recess formed in a rear end portion of a cutting tool inserted into a tool insertion hole of the collet.

Abstract: A numerical control system diagnoses and maintains a numerical control machine tool by measuring backlash and downloading a backlash correction value to the numerical control machine tool. The system includes a host computer device that downloads a monitor management program to a numerical controller of the numerical control machine tool, collects numerical control information input/output between the numerical controller and a servomotor, analyzes the numerical control information, and diagnoses the numerical control machine tool.

Abstract: A system determining whether the feed shafts are normal or abnormal, the system including: a command generation unit that moves the feed shafts in a forward direction at a predetermined speed from a lower limit value to an upper limit value of a range of feeding movement by the numerical controller; and a feed shaft abnormality determination unit that monitors a drive torque command during the movement of the feed shafts in the forward direction by the command generation unit, compares a monitoring result during the movement in the forward direction with a normal value of the drive torque command, determines that abnormality occurs when the drive torque command deviates from the normal value, and outputs the determination result.

Abstract: A host computer device downloads a monitor management program to a numerical controller of an NC machine tool in step S10, collects numerical control information input/output between the numerical controller and a servomotor in step S30, analyzes numerical control information monitored in step S40, and diagnoses the NC machine tool in steps S50 to S110.

Abstract: A system determining whether the feed shafts are normal or abnormal, the system including: a command generation unit that moves the feed shafts in a forward direction at a predetermined speed from a lower limit value to an upper limit value of a range of feeding movement by the numerical controller; and a feed shaft abnormality determination unit that monitors a drive torque command during the movement of the feed shafts in the forward direction by the command generation unit, compares a monitoring result during the movement in the forward direction with a normal value of the drive torque command, determines that abnormality occurs when the drive torque command deviates from the normal value, and outputs the determination result.

Abstract: A tool holder attachment structure includes a spindle and a tool holder. The spindle has a tip end face and a tapered hole. The tool holder has a tapered shank portion and a flange end face. In a clamped state, there is a clearance of a predetermined size between the flange end face of the tool holder and the tip end face of the spindle. As the spindle is rotated, the tapered hole of the spindle is slightly expanded by a centrifugal force caused by rotation of the spindle, and the presence of this clearance allows the tapered shank portion to be further drawn into the tapered hole so that the flange end face of the tool holder closely contacts the tip end face of the spindle, and the tapered shank portion is closely fitted in the tapered hole, whereby two-face restraint is implemented.

Abstract: In a shank portion of an end mill which is chucked by a tool holder, flat surfaces are formed at a plurality of circumferential positions in the outer periphery of the shank portion so that the flat surfaces abut on side lock bolts attached to a body of the tool holder.

Abstract: In a shank portion of an end mill which is chucked by a tool holder, flat surfaces are formed at a plurality of circumferential positions in the outer periphery of the shank portion so that the flat surfaces abut on side lock bolts attached to a body of the tool holder.

Abstract: In a shank portion of an end mill which is chucked by a tool holder, flat surfaces are formed at a plurality of circumferential positions in the outer periphery of the shank portion so that the flat surfaces abut on side lock bolts attached to a body of the tool holder.

Abstract: A tool holder attachment structure includes a spindle and a tool holder. The spindle has a tip end face and a tapered hole. The tool holder has a tapered shank portion and a flange end face. In a clamped state, there is a clearance of a predetermined size between the flange end face of the tool holder and the tip end face of the spindle. As the spindle is rotated, the tapered hole of the spindle is slightly expanded by a centrifugal force caused by rotation of the spindle, and the presence of this clearance allows the tapered shank portion to be further drawn into the tapered hole so that the flange end face of the tool holder closely contacts the tip end face of the spindle, and the tapered shank portion is closely fitted in the tapered hole, whereby two-face restraint is implemented.

Abstract: In a shank portion of an end mill which is chucked by a tool holder, flat surfaces are formed at a plurality of circumferential positions in the outer periphery of the shank portion so that the flat surfaces abut on side lock bolts attached to a body of the tool holder.

Abstract: A tool holder, which is inserted into a center-through-coolant spindle and employs a side-lock type chuck structure, can reliably prevent leakage of cutting liquid from a bolt hole for a side-lock bolt. The tool holder includes a side-lock bolt and an annular seal member. The side-lock bolt is inserted into a through hole extending from an outer peripheral surface to an inner peripheral surface of a tool attachment portion, threadedly engaged with an internal thread formed in the through hole, and secures a shank of a tool to a tool-holding bore. The seal member seals between the through hole and side-lock bolt.

Abstract: A wrench includes a wrench body having a ring portion and a handle portion. A retainer that holds a plurality of wedge members is disposed inside the ring portion. Wedge guide grooves are formed on the inner circumferential surface of the ring portion. Each of the wedge guide grooves has a free region which maintains the corresponding wedge member in a free state, and left-hand and right-hand wedge regions each of which maintains the corresponding wedge member in a caught state. The wrench is provided with a changeover mechanism for moving the retainer to a position at which the wedge member faces the corresponding free region, a position at which the wedge member faces the corresponding left-hand wedge region, or a position at which the wedge member faces the corresponding right-hand wedge region.

Abstract: A wrench includes a wrench body having a ring portion and a handle portion. A retainer that holds a plurality of wedge members is disposed inside the ring portion. Wedge guide grooves are formed on the inner circumferential surface of the ring portion. Each of the wedge guide grooves has a free region which maintains the corresponding wedge member in a free state, and left-hand and right-hand wedge regions each of which maintains the corresponding wedge member in a caught state. The wrench is provided with a changeover mechanism for moving the retainer to a position at which the wedge member faces the corresponding free region, a position at which the wedge member faces the corresponding left-hand wedge region, or a position at which the wedge member faces the corresponding right-hand wedge region.

Abstract: A wrench includes a wrench body having a ring portion and a handle portion. A retainer that holds a plurality of wedge members at predetermined intervals in a circumferential direction of the ring portion is disposed inside the ring portion. Wedge guide grooves are formed on the inner circumferential surface of the ring portion to be arranged at intervals corresponding to those of the wedge members. Each of the wedge guide grooves has a free region which maintains the corresponding wedge member in a free state in which the wedge member moves freely between a bottom surface of the corresponding wedge guide groove and the outer circumferential surface of a fastening member, and left-hand and right-hand wedge regions each of which maintains the corresponding wedge member in a caught state in which the wedge member is caught between the bottom surface of the corresponding wedge guide groove and the outer circumferential surface of the fastening member.

Abstract: A wrench includes a wrench body having a ring portion and a handle portion. A retainer that holds a plurality of wedge members at predetermined intervals in a circumferential direction of the ring portion is disposed inside the ring portion. Wedge guide grooves are formed on the inner circumferential surface of the ring portion to be arranged at intervals corresponding to those of the wedge members. Each of the wedge guide grooves has a free region which maintains the corresponding wedge member in a free state in which the wedge member moves freely between a bottom surface of the corresponding wedge guide groove and the outer circumferential surface of a fastening member, and left-hand and right-hand wedge regions each of which maintains the corresponding wedge member in a caught state in which the wedge member is caught between the bottom surface of the corresponding wedge guide groove and the outer circumferential surface of the fastening member.