A machine tool, in particular multi-spindle turning machine, comprising a machine frame, a turret body being rotatably supported by the machine frame, a plurality of workpiece spindles being arranged on the turret body, each of the workpiece spindles having a workpiece receiving portion for receiving a respective workpiece on one side of the turret body facing a working space of the machine tool, and a plurality of tool post assemblies supported by the machine frame around the turret body, wherein each tool post assembly includes a tool post having one or more tool cartridge receiving openings respectively being configured to detachably receive a tool holder cartridge TC holding a tool.

A machining unit for a machine tool and machine tool having such a machining unit comprises a head carrier that is attached to the machine tool, a pivot head held on the head carrier in such a way that the pivot head can be pivoted about a pivot axis, a working spindle, which is arranged on the pivot head and has a spindle axis that is tilted in relation to the pivot axis, a spindle motor, which is arranged in the head carrier and has a drive shaft arranged parallel to the pivot axis, and a drive transmission for transmitting the rotational motion of the drive shaft of the spindle motor to the working spindle, wherein the drive transmission has a transmission stage that can be shifted. The pivot head has a shifting transmission shaft that is oriented coaxially to the pivot axis of the pivot head, wherein the transmission stage that can be shifted has a hollow shaft movably supported on the shifting transmission shaft of the pivot head.

A machining unit for a machine tool and machine tool having such a machining unit comprises a head carrier that is attached to the machine tool, a pivot head held on the head carrier in such a way that the pivot head can be pivoted about a pivot axis, a working spindle, which is arranged on the pivot head and has a spindle axis that is tilted in relation to the pivot axis, a spindle motor, which is arranged in the head carrier and has a drive shaft arranged parallel to the pivot axis, and a drive transmission for transmitting the rotational motion of the drive shaft of the spindle motor to the working spindle, wherein the drive transmission has a transmission stage that can be shifted. The pivot head has a shifting transmission shaft that is oriented coaxially to the pivot axis of the pivot head, wherein the transmission stage that can be shifted has a hollow shaft movably supported on the shifting transmission shaft of the pivot head.

A temperature acquisition section (acquisition module) acquires a temperature of an environment in which a printer device is used. A printing condition acquisition section (acquisition module) acquires information relating to printing conditions of the printer device. A conveyance load estimation section (estimation module) estimates a conveyance load when a stepping motor (motor) provided in the printer device conveys a printing paper (print medium) based on the information acquired by the temperature acquisition section and the printing condition acquisition section. A current value setting section (setting module) sets a current value to be applied to the stepping motor based on the conveyance load estimated by the conveyance load estimation section. A motor control section (control module) controls the stepping motor by applying the current value set by the current value setting section to the stepping motor.

A temperature acquisition section (acquisition module) acquires a temperature of an environment in which a printer device is used. A printing condition acquisition section (acquisition module) acquires information relating to printing conditions of the printer device. A conveyance load estimation section (estimation module) estimates a conveyance load when a stepping motor (motor) provided in the printer device conveys a printing paper (print medium) based on the information acquired by the temperature acquisition section and the printing condition acquisition section. A current value setting section (setting module) sets a current value to be applied to the stepping motor based on the conveyance load estimated by the conveyance load estimation section. A motor control section (control module) controls the stepping motor by applying the current value set by the current value setting section to the stepping motor.

A method to control a power tool, especially a core drill, including a motor as the drive for the power tool, a control unit, a power display, a transmission having at least a first gear and a second gear, a first sensor to detect the rotational speed of at least one component of the transmission and a second sensor to detect the rotational speed of the motor. The method includes the following steps: ascertaining a first rotational speed of the at least one component of the transmission when the transmission has been put into a gear, ascertaining a first rotational speed of the motor when the transmission has been put into a gear, ascertaining the selection of the gear on the basis of a first prescribed ratio of the first rotational speed of the at least one component of the transmission and of the first rotational speed of the motor on the basis of a look-up table, and setting the limit value of the power display on the basis of the look-up table as a function of the gear that has been selected. A power tool for purposes of using the method.

A speed change auxiliary device of a lathe is provided. A side chamber of the lathe is provided with a shaft seat and a bottom shaft seat at the top and bottom thereof. An auxiliary device is provided between the shaft seat and the bottom shaft seat. The auxiliary device includes a shaft. A spring, an eccentric block, an engaging member, a positioning nut, a rotary sleeve and a fixing block are fitted on the shaft. The rotary sleeve includes a handle. Two sides of an inner circumferential surface of the rotary sleeve have protrusions. The protrusions each have an upright surface and an upper guide bevel at two sides thereof. The fixing block is disposed on the bottom shaft seat. Two sides of a circumferential surface of the fixing block have recesses. The recesses each have a stop surface and a lower guide bevel at two sides thereof.

A speed change auxiliary device of a lathe is provided. A side chamber of the lathe is provided with a shaft seat and a bottom shaft seat at the top and bottom thereof. An auxiliary device is provided between the shaft seat and the bottom shaft seat. The auxiliary device includes a shaft. A spring, an eccentric block, an engaging member, a positioning nut, a rotary sleeve and a fixing block are fitted on the shaft. The rotary sleeve includes a handle. Two sides of an inner circumferential surface of the rotary sleeve have protrusions. The protrusions each have an upright surface and an upper guide bevel at two sides thereof. The fixing block is disposed on the bottom shaft seat. Two sides of a circumferential surface of the fixing block have recesses. The recesses each have a stop surface and a lower guide bevel at two sides thereof.

A machine tool, in particular multi-spindle turning machine, comprising a machine frame, a turret body being rotatably supported by the machine frame, a plurality of workpiece spindles being arranged on the turret body, each of the workpiece spindles having a workpiece receiving portion for receiving a respective workpiece on one side of the turret body facing a working space of the machine tool, and a plurality of tool post assemblies supported by the machine frame around the turret body, wherein each tool post assembly includes a tool post having one or more tool cartridge receiving openings respectively being configured to detachably receive a tool holder cartridge TC holding a tool.

A machine control system for a multi-spindle machine includes a controller (42, 86). The controller is operative to reduce the risk of potentially damaging machining chip formation by controlled disengagement of a low speed clutch (18) of a transmission (14) which drives spindles (36) which rotate work pieces. Automatically selectively varying timing and duration of periods of disengagement of the low speed clutch breaks the continuity of chips to reduce the risk of developing damaging conditions as a result thereof.