A lathe includes a spindle, an opposite spindle, a tool post, a controller, and a contact-type breakage detector. The controller determines whether the cut-off tool is broken according to a control parameter for controlling at least one of the spindle and the opposite spindle at a first detection timing immediately after the cut-off tool cuts off the bar material while the opposite spindle holds the bar material held by the spindle. The controller determines whether the cut-off tool is broken according to a detection result by the contact-type breakage detector at a second detection timing different from the first detection timing.

Provided is a machine tool capable of facilitating switching moving ranges of the moving unit. A moving-side cover provided on the moving unit covers part of a position of the driving apparatus in the moving direction. A supporting-side cover is provided in a position on a side of the first moving range of an end of the moving-side cover on a side of the second moving range in the moving direction to continuously cover the part of the position of the driving apparatus in the moving direction in cooperation with the moving-side cover in the first use state. The supporting-side cover forms a clearance in the moving direction with respect to the moving-side cover in the second use state. A slide cover is mounted on one of supporting-side cover and the moving-side cover slidably in the moving direction to close the clearance when slidably drawn out in the moving direction.

Provided is a machine tool capable of facilitating switching moving ranges of the moving unit. A moving-side cover provided on the moving unit covers part of a position of the driving apparatus in the moving direction. A supporting-side cover is provided in a position on a side of the first moving range of an end of the moving-side cover on a side of the second moving range in the moving direction to continuously cover the part of the position of the driving apparatus in the moving direction in cooperation with the moving-side cover in the first use state. The supporting-side cover forms a clearance in the moving direction with respect to the moving-side cover in the second use state. A slide cover is mounted on one of supporting-side cover and the moving-side cover slidably in the moving direction to close the clearance when slidably drawn out in the moving direction.

A machine tool and a controller for the machine tool that accurately detect a defect in a cutting-off process due to breakage of a cutting-off bit and the like is provided. The machine tool includes: a spindle 110 for holding one end side of a workpiece W; an opposed chuck 131 that is opposed to the spindle 110 and is movable with holding another end side of the workpiece W; and a spindle moving motor 122 for moving the spindle 110. The machine tool or the controller is provided with a load detector 172 for detecting a load of the spindle moving motor 122, and workpiece separation detector 173 for detecting a defect in a cutting-off process from the load in performing a taking out operation.

The invention provides a machine tool capable of facilitating a switching between a guide bush mode and a non-guide bush mode. A machine tool comprises a headstock provided with a main spindle for gripping a workpiece, a rail extended along a main spindle axis, a first bearing fixed to the headstock and guided on the rail, a second bearing fixed to the headstock on the front side of the first bearing and guided on the rail, a supporting bed on which a guide bush is removably mounted, and a guide mounted on the supporting bed to movably support the headstock in a direction of the main spindle axis when the guide bush is removed. The rail provides a larger play on the second bearing when the headstock is supported by the guide than when the headstock is not supported by the guide.

The invention provides a machine tool capable of facilitating a switching between a guide bush mode and a non-guide bush mode. A machine tool comprises a headstock provided with a main spindle for gripping a workpiece, a rail extended along a main spindle axis, a first bearing fixed to the headstock and guided on the rail, a second bearing fixed to the headstock on the front side of the first bearing and guided on the rail, a supporting bed on which a guide bush is removably mounted, and a guide mounted on the supporting bed to movably support the headstock in a direction of the main spindle axis when the guide bush is removed. The rail provides a larger play on the second bearing when the headstock is supported by the guide than when the headstock is not supported by the guide.

A machine tool comprising: a first spindle; a second spindle provided on a rear headstock to face the first spindle; a barstock supply unit for supplying an elongate rod to the first spindle; and a processing means including a tool for processing the barstock, characterized in that the machine tool further comprises: a workpiece clamp device provided on the rear headstock and adapted to grip a second material comprised of the barstock that has been removed from the first spindle as an old material; and a joining means for joining opposite end portions of the second material gripped by the workpiece clamp device and of a first material gripped by the first gripping means and comprised of a barstock newly supplied by the barstock supply unit, thereby to integrate the second material and the first material into a single barstock.

A machine tool comprising: a first spindle; a second spindle provided on a rear headstock to face the first spindle; a barstock supply unit for supplying an elongate rod to the first spindle; and a processing means including a tool for processing the barstock, characterized in that the machine tool further comprises: a workpiece clamp device provided on the rear headstock and adapted to grip a second material comprised of the barstock that has been removed from the first spindle as an old material; and a joining means for joining opposite end portions of the second material gripped by the workpiece clamp device and of a first material gripped by the first gripping means and comprised of a barstock newly supplied by the barstock supply unit, thereby to integrate the second material and the first material into a single barstock.

A material bar magazine for guiding material bars on an automatic lathe and a system having such a magazine and automatic lathe having at least one headstock that is displaceable along a longitudinal axis of the material bar magazine, where the material bar magazine includes a material bar-guiding channel system having a channel opening system. Further, the channel system of the material bar magazine has a first, outer guide channel and a second, inner guide channel mounted inside the first guide channel such that it can move relative thereto along the longitudinal direction, the second, inner guide channel couplable or coupled to the headstock of the automatic lathe for moving the second, inner guide channel as a result of a change in position of the headstock along a longitudinal axis of the material bar magazine in overrun condition synchronously therewith along the longitudinal axis and relative to the first guide channel.

According to one embodiment, a sensor attachment/detachment device of the embodiment includes a sensor, a bonding member, a support portion, and a release execution portion. The bonding member is bonded to a first surface of the sensor and has a function of decreasing an adhesive force. The support portion can support the sensor by directly contacting a second surface of the sensor or via another functional portion. The release execution portion performs a process of releasing the bonding member from the object by decreasing the adhesive force of the bonding member after the sensor is attached to the object by the bonding member.