A machine tool includes a plurality of modules, and a control means for controlling operation of the modules, wherein the plurality of modules include a fixed module and two movable modules. The control means includes a restriction means for restricting the movement of the two movable modules for allowing only one of the movable modules to be moved to a facing position facing the fixed module; and a determination means for determining the movable module to be moved to the facing position. The control means is configured to control the operation of the plurality of modules so that, when the operation under cooperation of the fixed module and one of the movable modules has been completed, the restriction means releases the restriction of the movement of the other movable module to the facing position.

A conveying device includes a workpiece pressing member and a switching member. The workpiece pressing member is able to move along a conveyance path when a mobile body moves, and also moves a workpiece downstream of the conveyance path by moving downstream of the conveyance path while pressing the workpiece. The switching member is able to move along the conveyance path as the mobile body moves, and switches between an engaged state and a non-engaged state with the workpiece pressing member depending on whether the movement is in downstream and upstream directions. When the switching member moves downstream, the workpiece pressing member is able to press the workpiece, and, when the switching member moves upstream, the workpiece pressing member is able to avoid coming into contact with the workpiece.

A conveying device includes a workpiece pressing member and a switching member. The workpiece pressing member is able to move along a conveyance path when a mobile body moves, and also moves a workpiece downstream of the conveyance path by moving downstream of the conveyance path while pressing the workpiece. The switching member is able to move along the conveyance path as the mobile body moves, and switches between an engaged state and a non-engaged state with the workpiece pressing member depending on whether the movement is in downstream and upstream directions. When the switching member moves downstream, the workpiece pressing member is able to press the workpiece, and, when the switching member moves upstream, the workpiece pressing member is able to avoid coming into contact with the workpiece.

A machining system which includes a plurality of machine tools each having an independent operation part and controller, and shared peripheral equipment associated with all of the plurality of machine tools, includes a shared controller for the shared peripheral equipment which is operable by each of the operation parts of the plurality of machine tools, wherein the shared controller includes an authorization part for granting operation authority to one of the operation parts of the plurality of the machine tools.

A machining system which includes a plurality of machine tools each having an independent operation part and controller, and shared peripheral equipment associated with all of the plurality of machine tools, includes a shared controller for the shared peripheral equipment which is operable by each of the operation parts of the plurality of machine tools, wherein the shared controller includes an authorization part for granting operation authority to one of the operation parts of the plurality of the machine tools.

A lathe includes a lathe-side chuck that holds a workpiece with the workpiece directed toward or facing a front side, a main spindle that rotates around an axis, and a tool that machines the workpiece. A machining center includes a rotary tool that rotates around an axis in the horizontal direction and an MC-side chuck that holds the workpiece and is able to turn between at least a workpiece pass/receive position in which the workpiece is directed toward or facing the front side and a machining position in which the workpiece is directed toward or facing the rotary tool. A loader includes a guide rail extending above the lathe-side chucks, and MC-side chuck along the horizontal direction and a loader head that holds the workpiece and carries the workpiece between at least the lathe-side chucks, and MC-side chuck by moving along the guide rail.

A lathe includes a lathe-side chuck that holds a workpiece with the workpiece directed toward or facing a front side, a main spindle that rotates around an axis, and a tool that machines the workpiece. A machining center includes a rotary tool that rotates around an axis in the horizontal direction and an MC-side chuck that holds the workpiece and is able to turn between at least a workpiece pass/receive position in which the workpiece is directed toward or facing the front side and a machining position in which the workpiece is directed toward or facing the rotary tool. A loader includes a guide rail extending above the lathe-side chucks, and MC-side chuck along the horizontal direction and a loader head that holds the workpiece and carries the workpiece between at least the lathe-side chucks, and MC-side chuck by moving along the guide rail.

In an embodiment, a machine tool includes two fixed modules and two movable modules each of which having a main spindle, a headstock, and a tool post being integrally formed, and a bed on which these are installed. The movable modules are provided on the bed to be movable in the Y-axis direction, the fixed modules are fixed on the bed on the opposite sides of the these movable modules, and a recess is provided next to the fixed module, the recess being formed by cutting out the bed. The movable modules are movable such that the axis lines of the main spindles of the movable modules are aligned with the axis line of the main spindle of the fixed module or the fixed module. The movable module is movable to the opposite position of the recess.

In an embodiment, a machine tool includes two fixed modules and two movable modules each of which having a main spindle, a headstock, and a tool post being integrally formed, and a bed on which these are installed. The movable modules are provided on the bed to be movable in the Y-axis direction, the fixed modules are fixed on the bed on the opposite sides of the these movable modules, and a recess is provided next to the fixed module, the recess being formed by cutting out the bed. The movable modules are movable such that the axis lines of the main spindles of the movable modules are aligned with the axis line of the main spindle of the fixed module or the fixed module. The movable module is movable to the opposite position of the recess.

A machining center including a machine main body, an upper section of which supports a head moving device and a head raising and lowering device, configured such that a tool magazine is stored inside the machine main body, and with a magazine moving device configured to move the tool magazine such that, during tool exchange, the tool magazine is advanced to protrude from a side of the machine main body, so that, from the multiple tool holders, the tool holder used for exchange is positioned inside the movement range of the main shaft by the head moving device, and wherein the entire tool magazine is able to be moved beyond the movement range of the tool magazine by the magazine moving device to a position outside of the machine main body and detached from the machine main body.