Abstract: For a spring sliding on the drawbar, the coil spring is used; the removal work for keeping the inner diameters of the coil springs aligned is performed such that the clearance between the outer diameter of the drawbar and the inner diameter of the coil spring becomes a minimum; and the coil springs are caused to be guided integrally with the drawbar. By doing so, the movement of the center of gravity of the spring that is caused by repeated rotational operation of the main spindle or repeated tool clamping operation will be reduced and the amplitude by vibration will be made smaller.

Abstract: A numerically controlled machine tool performs machining by rotating a rotational tool attached to a tool holder mounted on a spindle, with keys fitted into key grooves in the tool holder. The numerically controlled machine tool includes predetermined-amount rotating unit for stopping the tool holder at a predetermined rotational position and then rotating the tool holder by a given amount, and a distance sensor which is installed apart from the tool holder and measures a distance to the outer surface of the tool holder. The predetermined-amount rotating unit stops the tool holder at a rotational position at which the key grooves do not face the distance sensor, then rotates the tool holder by the given amount. The distance sensor measures the distance to the tool holder while the tool holder is rotating. The measurement result is compared with a reference distance or distances to discriminate between normal and abnormal rotational run-out of the tool holder.

Abstract: A telescopic cover which relieves impact caused when a cover member is stopped moving and which is less meandering. A braking mechanism is provided between one of two adjacent cover members of the telescopic cover and the other of the two adjacent cover members which telescopically moves into and out of the one cover member. The braking mechanism is provided at a distal end portion of the one cover member, and has an elastic member that presses a slide member against the other cover member. When the other cover member moves relatively to the one cover member, a friction force generated by a pressing force of the slide member serves to brake the movement of the other cover member, whereby impact caused when the other cover member stops moving is relieved. The cover member in motion is always pressed by the slide member with an orientation thereof maintained.

Abstract: An automatic tool changer in which the load produced when a turret is rotation-driven is reduced, and abrasion in the balls and the like of a speed reducer, and mal-distribution of an axial pressing force are prevented. The speed reducer that drives the turret in the automatic tool changer is constructed by superposing a driving plate, a holder, and a driven plate in the order named. In the driven plate fitted with tools, there is formed a ball groove in a concave-convex shape having the number of cycles corresponding to the number of the tools. In the driving plate, there is provided a ball groove obtained by enlarging the ball groove of the driven plate in the angular direction and copying two cycles. The holder is provided with a plurality of guide holes in the radial direction, which hold their respective balls. The driving plate is rotated by spindle rotation, and the driven plate is driven at a reduced speed of (the number of tools/2) through the balls.

Abstract: An automatic tool changing method and an automatic tool changing device for a machine tool with a numerical controller capable of reducing the occurrence of impact due to tool exchange with a simple structure. A turret that rotates about a pivot shaft is provided on an arm and holds multiple tools. A swing cam CS that cooperates with a swing roller provided on the turret is provided on a spindle head. As the spindle head descends the turret rotates due to the action of the swing roller and the cam CS and exchanges tools. In order to lessen the impact that occurs at this time, the velocity of the spindle head is controlled. The ideal swing velocity pattern for the turret is obtained, and from this swing velocity pattern the swing position of the turret at each moment is obtained. From the swing roller and cam CS positions at this position the position of the spindle head 34 is obtained.

Abstract: A tool changing device and a tool cleaning method capable of surely removing foreign matter such as swarf adhered to tapered portions and/or flange portions of tools, which serve as contact faces to be in contact with a spindle. There is arranged tool cleaning nozzles for spouting coolant on both sides of the spindle in the rotating position of a turret. The tool cleaning nozzle has a position and a posture such that the coolant spouted from the nozzle hits against the tapered portions and/or the flange portions of the tools held by the turret. The coolant is spouted from the tool cleaning nozzle with the rotation of the turret at the time of tool selection. Each time the turret rotates, the tapered portions and/or the flange portions of the tools held by the turret are cleaned by the coolant.

Abstract: A stationary machine tool column supports a spindle head to be movable in an axial direction of the spindle. A table on which a workpiece is mounted is moved in directions orthogonal to the axial direction of the spindle. A cutting liquid feed device is fixed to the column through a support member and includes a cutting liquid nozzle and a shower nozzle. The cutting liquid nozzle is adapted to discharge cutting liquid toward a tool mounted to the spindle. The shower nozzle is adapted todischarge cutting liquid as a curtain of fluid to surround a cutting area.

Abstract: In a pallet changer that changes pallets for mounting workpieces on a machine tool work table, a pallet changer clamping mechanism that clamps and unclamps a workpiece-mounting pallet to and from the work table, the pallet changer clamping mechanism comprising a workpiece-mounting pallet whose direction of delivery to and removal from the work table is the same as its direction of movement for clamping and unclamping. The workpiece-mounting pallet moves on a plane parallel to the work table when clamped to and unclamped from the work table.

Abstract: An automatic tool changer in which the load produced when a turret is rotation-driven is reduced, and abrasion in the balls and the like of a speed reducer, and mal-distribution of an axial pressing force are prevented. The speed reducer that drives the turret in the automatic tool changer is constructed by superposing a driving plate, a holder, and a driven plate in the order named. In the driven plate fitted with tools, there is formed a ball groove in a concave-convex shape having the number of cycles corresponding to the number of the tools. In the driving plate, there is provided a ball groove obtained by enlarging the ball groove of the driven plate in the angular direction and copying two cycles. The holder is provided with a plurality of guide holes in the radial direction, which hold their respective balls. The driving plate is rotated by spindle rotation, and the driven plate is driven at a reduced speed of (the number of tools/2) through the balls.

Abstract: An automatic tool changing device capable of cleaning a contact surface of a spindle, which is to be in contact with a tool holder, with a simple structure. The device includes a turret having a plurality of grippers on its outer circumference and holding the tool holder by means of the grippers. At the time of tool change, the grippers grip and pull out the tool holder fixed to the spindle. Rotation of the spindle causes the turret to rotate through a spindle gear, a turret gear, and a decelerating device, to thereby select a tool. At this moment, a coolant is spouted from a nozzle portion of a manifold toward a spindle taper hole in which the tool holder is interfitted and washes the taper hole. Due to the rotation of the spindle, the coolant is spouted onto the whole circumference of the taper hole, and the surface to be in contact with the tool holder is surely washed.

Abstract: For a spring sliding on the drawbar, the coil spring is used; the removal work for keeping the inner diameters of the coil springs aligned is performed such that the clearance between the outer diameter of the drawbar and the inner diameter of the coil spring becomes a minimum; and the coil springs are caused to be guided integrally with the drawbar. By doing so, the movement of the center of gravity of the spring that is caused by repeated rotational operation of the main spindle or repeated tool clamping operation will be reduced and the amplitude by vibration will be made smaller.

Abstract: A numerically controlled machine tool performs machining by rotating a rotational tool attached to a tool holder mounted on a spindle, with keys fitted into key grooves in the tool holder. The numerically controlled machine tool includes predetermined-amount rotating unit for stopping the tool holder at a predetermined rotational position and then rotating the tool holder by a given amount, and a distance sensor which is installed apart from the tool holder and measures a distance to the outer surface of the tool holder. The predetermined-amount rotating unit stops the tool holder at a rotational position at which the key grooves do not face the distance sensor, then rotates the tool holder by the given amount. The distance sensor measures the distance to the tool holder while the tool holder is rotating. The measurement result is compared with a reference distance or distances to discriminate between normal and abnormal rotational run-out of the tool holder.

Abstract: A tool holder is attached to a spindle by the contacting of the projecting cone part and end surface of the tool holder with the recessed cone part and end surface of the spindle respectively. A toroidal cone section is provided on the inner side surface of the recessed cone part of the spindle so as to protrude inward. The diameter of the toroidal cone section is formed smaller than the diameter of the section of the projecting cone part of the tool holder that abuts the toroidal cone section.

Abstract: A telescopic cover which relieves impact caused when a cover member is stopped moving and which is less meandering. A braking mechanism is provided between one of two adjacent cover members of the telescopic cover and the other of the two adjacent cover members which telescopically moves into and out of the one cover member. The braking mechanism is provided at a distal end portion of the one cover member, and has an elastic member that presses a slide member against the other cover member. When the other cover member moves relatively to the one cover member, a friction force generated by a pressing force of the slide member serves to brake the movement of the other cover member, whereby impact caused when the other cover member stops moving is relieved. The cover member in motion is always pressed by the slide member with an orientation thereof maintained.

Abstract: A tool changing device and a tool cleaning method capable of surely removing foreign matter such as swarf adhered to tapered portions and/or flange portions of tools, which serve as contact faces to be in contact with a spindle. There is arranged tool cleaning nozzles for spouting coolant on both sides of the spindle in the rotating position of a turret. The tool cleaning nozzle has a position and a posture such that the coolant spouted from the nozzle hits against the tapered portions and/or the flange portions of the tools held by the turret. The coolant is spouted from the tool cleaning nozzle with the rotation of the turret at the time of tool selection. Each time the turret rotates, the tapered portions and/or the flange portions of the tools held by the turret are cleaned by the coolant.

Abstract: An automatic tool changing device capable of cleaning a contact surface of a spindle, which is to be in contact with a tool holder, with a simple structure. The device includes a turret having a plurality of grippers on its outer circumference and holding the tool holder by means of the grippers. At the time of tool change, the grippers grip and pull out the tool holder fixed to the spindle. Rotation of the spindle causes the turret to rotate through a spindle gear, a turret gear, and a decelerating device, to thereby select a tool. At this moment, a coolant is spouted from a nozzle portion of a manifold toward a spindle taper hole in which the tool holder is interfitted and washes the taper hole. Due to the rotation of the spindle, the coolant is spouted onto the whole circumference of the taper hole, and the surface to be in contact with the tool holder is surely washed.

Abstract: A machine tool has a column that supports a spindle head in such a manner as to be movable in an axial direction of the spindle. A table on which a workpiece is mounted is moved in directions orthogonal to the axial direction of the spindle. A cutting liquid feed device is fixed to the column through a support member. The cutting liquid feed device includes a cutting liquid nozzle and a shower nozzle. The cutting liquid nozzle is adapted to discharge the cutting liquid toward a tool mounted to the spindle. The shower nozzle is adapted to discharge the cutting liquid in a shape of film (shower curtain) so as to surround a cutting area.

Abstract: A fixed first sleeve and a movable second sleeve are arranged in a center through hole of a main spindle. Balls at the rear end of the second sleeve engage a recessed slope of the first sleeve and a recessed slope of a draw bar, thereby amplifying the urging force of a spring for urging the draw bar upward. Balls at the distal end of the second sleeve hold and pull in the head of the pull stud with the amplified force. The pull stud has an axial through hole and a hole that connects with the through hole and opens sideways. Compressed air passes through these holes, thereby cleaning the respective taper surfaces and end faces of the main spindle and a tool shank. Switching means is used to close the hole that opens sideways, whereby a cutting fluid is allowed to flow through the axial through hole only.

Abstract: A feed-shaft moving method and an apparatus capable of reducing non-cutting motion time. In a first section and a second section, an immediately preceding path is connected with a rapid traverse by a rapid traverse motion path having a curve continuous with the immediately preceding path. The movement is accelerated up to a rapid traverse speed while passing the curve. In the first section, the path is connected with the next path by a rapid traverse path having a curve continuous with the next movement. The movement is decelerated to the next moving speed while passing the curve. The rapid traverse motion of the feed shaft can be completed in less time, with unnecessary interruption and with no impact on the machine.

Abstract: A machining method in which a numerically controlled apparatus carries out a series of operations such as the determination of machining procedures, the selection of a tool, the preparation of a workpiece and inspection programs, machining operation, and inspection, required when a numerically controlled machine tool carries out a machining operation on the basis of input graphics and process information, using at least machine tool information, tool information, cutting condition information, material information, machining method symbol information, finishing symbol information, finishing allowance information, surface treatment information, information about thermal refining, and cost information, the method includes the steps of, while using electronic calculators including a numerical control unit, an FA system, and a personal computer, and a series of data processing units and machine tools, registering a variety of information files; inputting machining pattern data; processing a finished pattern; proc