A workpiece is conveyed from a first fixed point to a second fixed point by a conveyor in a chucked state. A phase of the workpiece that is being conveyed by the conveyor is detected by a detector. The workpiece conveyed to the second fixed point by the conveyor is seated on a seating part. A workpiece seating phase of the seating part is adjusted by an adjustor to the phase of the workpiece detected by the detector.

A machine tool includes a rotatable spindle, a spindle drive, a tool magazine, a tool changer including a rotating shaft, a rotating shaft drive motor, an angular position detector, a tool change arm having gripping units at both ends, and a controller. After interchanging a first tool mounted on the spindle and a second tool held in a tool pot, when rotating the tool change arm to an intermediate position, rotation of the spindle is started as soon as the second tool mounted on the spindle and the gripping unit are out of contact with each other.

A machining apparatus includes a first frame including a first surface formed along a Z-axis direction and a second surface formed along a Y-axis direction. An X-axis moving mechanism and a Z-axis moving mechanism are disposed on the first surface side of the first frame. A Y-axis moving mechanism is disposed on the second surface side of the first frame. A second frame supports the first frame from the second surface side of the first frame. An A-axis rotating mechanism, a B-axis rotating mechanism, and a supporting mechanism that supports an object to be machined are moved by the Y-axis moving mechanism. The t Y-axis moving mechanism is disposed in a space located below the first frame in the Z-axis direction, and formed by the second flame.

A technique for detecting the completion of work of attaching a workpiece to a pallet is provided. A pallet transport system includes: a transport device for transporting a pallet to which a workpiece can be attached; a pallet housing unit for housing the pallet, a workstation in which a worker is to conduct work of attaching the workpiece to the pallet transported from the pallet housing unit; a machine tool for machining the workpiece attached to the pallet in the workstation; and a control device for controlling the transport device. The control device acquires an indicator indicating progress of the attachment work in the workstation, determines whether or not the attachment work has been completed based on the indicator, and when it is determined that the attachment work has been completed, transports the pallet located in the workstation to the pallet housing unit or the machine tool.

Provided is an apparatus for detecting a failure in holding a tool of a machine tool that includes, in each of a plurality of tool holding mechanisms in a tool magazine, a locking member provided to have different self-displacement positions for a case where a tool is held at a proper held position between tool gripping portions of a pair of holding arms and a case where the tool is held with deviation from the proper held position, and that detects a holding failure state of the tool in the tool holding mechanism by detecting the position of a detection target portion that moves integrally with the locking member with a predetermined detector provided in the machine tool. The apparatus makes it possible to effectively prevent a risk of a breakdown of and damage to the machine tool.

A machine tool (1) includes: a front spindle (10) having a front chuck (12); a rear spindle (20) having a rear chuck (22); a controller (50) configured to cause the rear chuck (22) to perform a fastening operation for fastening a work (W) fastened to the front chuck (12) to the rear chuck (22); and a detector (60) configured to detect an abnormality caused by the fastening operation by the rear chuck (22), based on measurement data associated with a vibration of at least one of the front chuck (12) and the rear chuck (22).

A tailstock control device includes a tailstock parameter setting unit that receives, in advance, setting of tailstock acceleration time ta, tailstock movement velocity V, drive torque measuring period t, and number n of drive torque measurements; a calculating unit that calculates acceleration zone distance La from the acceleration time ta and the movement velocity V; a calculating unit that calculates constant velocity zone distance Lb from the movement velocity V, the measuring period t, and the number n of measurements; a drive torque detecting unit that detects servo motor drive torque; and a control unit that sets La+Lb as drive torque measuring distance Lt and calculates servo motor drive torque limit value c from drive torque T detected by the drive torque detecting unit when the tailstock is moved over La+Lb and also from a servo motor torque command value a required for supporting a workpiece.

Provided is a gripping method including: a phase matching step of matching tool relief grooves of a contact metal member and track grooves of a constant velocity universal joint component with each other in phase; a measuring step of measuring phase differences between the track grooves of the constant velocity universal joint component and a female spline of the constant velocity universal joint component; a matching step of matching, based on a result of the measuring step, a stopper with a recessed portion of the female spline having the smallest phase difference and gripping the constant velocity universal joint component by a collet chuck. Under a state in which the constant velocity universal joint component is gripped by the collet chuck, the contact metal member holds the constant velocity universal joint component.

Provided is technology which enables suitable control of a chuck holding force. In this machine tool comprising a main shaft provided with a chuck for holding a workpiece, when an open/close mechanism has performed a closing operation on the chuck such that the chuck enters a closed state from an open state, a holding force of the chuck on the workpiece in the closed state is acquired on the basis of the magnitude of a difference between a first time taken from when a control unit emits a control signal for the closing operation to the open/close mechanism to when a first sensor detects that the chuck is no longer in the open state, and a second time taken from when the control unit emits a control signal in an open/close mechanism to when a second sensor detects that the chuck has entered the closed state.