The present invention relates to a machine tool including a ram spindle and a tool holder, and provides a machine tool comprising: a tool holder including at least two inserts; and a ram spindle capable of fixing the tool holder in a clamped state or rotating the tool holder in order to change the position of the insert, such that the position of the insert can be quickly changed, thereby enabling an improvement in productivity and precision and a reduction in product costs.

A tool rest includes: a tool holder including a clamp mechanism that operates by an oil pressure for clamping a tool; an attachment portion having a hole through which a hydraulic oil for the clamp mechanism is supplied, the tool holder being detachably attached to the attachment portion; a valve body arranged in the hole and operable between a first state in which, when the tool holder is not attached, circulation of the hydraulic oil is regulated upon receiving a pressure of the hydraulic oil, and a second state in which, when the tool holder is attached, circulation of the hydraulic oil is permitted; and an elastic member that is arranged in the hole and exerts an elastic force on the valve body so as to operate the valve body from the second state to the first state.

A tool rest includes: a tool holder including a clamp mechanism that operates by an oil pressure for clamping a tool; an attachment portion having a hole through which a hydraulic oil for the clamp mechanism is supplied, the tool holder being detachably attached to the attachment portion; a valve body arranged in the hole and operable between a first state in which, when the tool holder is not attached, circulation of the hydraulic oil is regulated upon receiving a pressure of the hydraulic oil, and a second state in which, when the tool holder is attached, circulation of the hydraulic oil is permitted; and an elastic member that is arranged in the hole and exerts an elastic force on the valve body so as to operate the valve body from the second state to the first state.

A numerical controller includes a command analysis unit that generates movement command data by analyzing a program command and an axis travel calculation unit that, when the program command commands movement of a tool in a direction of a first straight axis orthogonal to an axis of rotation of a workpiece, converts a command value based on the program command for the movement of the tool in the direction of the first straight axis into a command value for a rotation angle of a turret, and a position of the tool is controlled in accordance with a rotation command for the turret based on the command value for the rotation angle of the turret calculated by the axis travel calculation unit, instead of the command based on the program command for the movement in the direction of the first straight axis.

A machine tool includes a main spindle that rotates while holding a workpiece, a mover that moves a cutting tool including a linear cutting blade that cuts the workpiece, with respect to the workpiece in a moving direction including at least a Z-direction parallel or substantially parallel with the axis of the main spindle and a Y-direction perpendicular or substantially perpendicular to both the Z-direction and an X-direction determining the amount of cutting of the workpiece, a holder that holds the cutting tool in a state in which the direction of the linear cutting blade is inclined with respect to the Z-direction by a predetermined angle when seen from the X-direction, and an angle adjuster that changes the edge angle.

A turret tool post includes a turret turnably supported by a post body, turret turning part having a turret turning shaft and the like to turn the turret, a tool attachment part turnably holding a rotatable tool and attached to the turret, and tool-attachment-part turning part turning the tool attachment part to turn the rotatable tool. The tool-attachment-part turning part and the turret turning part are provided independently and arranged to face each other. The tool-attachment-part turning part includes a tool turning motor installed inside the turret and an attachment-part transmission shaft connected to the tool turning motor.

A turret tool rest includes a main shaft, a turret turning shaft, a turret, a joint base, a mill housing connection shaft, and an engagement member. The main shaft rotates a tool. A part of the main shaft is provided in the turret turning shaft. The turret turning shaft has a first coupling hole. The turret is connected to the turret turning shaft via which the turret is rotated. The joint base has a second coupling hole. The mill housing connection shaft is connected to the joint base. The mill housing connection shaft is provided between the main shaft and the turret turning shaft. Each of the mill housing connection shaft, the joint base, the part of the main shaft, and the turret turning shaft are disposed to rotate around a rotation axis of the turret. The engagement member moves in the first coupling hole and the second coupling hole.

The present invention can realize better cutting performance while suppressing an influence of, for instance, deflection of a head and an increase in a moment acting on a fastening mechanism even when a cutting insert of a long total length is used. A shank of a head replaceable type cutting tool includes: a fastening mechanism that is formed at a leading end part in a longitudinal direction of the shank, and attaches a head; and a recessed part that is formed at the leading end part so as to accommodate a part of a cutting insert held by the head and avoid an interference with the cutting insert. The recessed part may be provided to accommodate a non-use part of the cutting insert held by the head in a state where the head is attached to the leading end part, and avoid an interference with the cutting insert.

The present invention can realize better cutting performance while suppressing an influence of, for instance, deflection of a head and an increase in a moment acting on a fastening mechanism even when a cutting insert of a long total length is used. A shank of a head replaceable type cutting tool includes: a fastening mechanism that is formed at a leading end part in a longitudinal direction of the shank, and attaches a head; and a recessed part that is formed at the leading end part so as to accommodate a part of a cutting insert held by the head and avoid an interference with the cutting insert. The recessed part may be provided to accommodate a non-use part of the cutting insert held by the head in a state where the head is attached to the leading end part, and avoid an interference with the cutting insert.

A lathe includes a tool holder having a holder reference point, and a tool having a tool nose is attachable to the tool holder. A tool post has a tool post origin and mounting surfaces. An actuator is to adjust each of the mounting surfaces to an indexing position. A memory stores first distances between the tool post origin and the holder reference point of the tool holder mounted on the mounting surfaces, respectively. The memory stores instructions that when executed by a processor, cause the processor to perform operations. The operations include obtaining a second distance between the holder reference point and the tool nose of the attached tool, and estimating, based on the first distances and second distance, a third distance between the tool post origin and the tool nose of the attached tool to control the actuator.