Abstract: In order to improve a spindle drive for machine tools, comprising a housing, a spindle mounted in the housing, a drive motor arranged on the housing and a gear arranged in the housing and comprising an intermediate shaft driven by the drive motor and mounted in the housing via two shaft bearings spaced from one another as well as a first gear wheel seated on the intermediate shaft, wherein for driving the spindle as C-axis the first gear wheel engages in a first position with a second gear wheel driving the spindle so as to mesh with the second gear wheel without clearance, such that it is more simple in construction it is suggested that the first shaft bearing fix the intermediate shaft immovably on the housing in a direction transverse to its axis and that the intermediate shaft be adapted to be moved back and forth by the second shaft bearing relative to the second gear wheel in an adjusting direction between the first position and a second position, the gear wheels meshing with one another in the second p

Abstract: Lathe comprising a main work spindle drivable by numerical control and a turret with several indexing stations, the turret having at least one drivable tool spindle, being mounted on a turret slide for rotation about a turret axis and being rotatable by numerical control about this axis by means of a turret driving device, and also comprising a switchable device for securing the turret against rotation. For positive locking of the turret and for play-free mounting of the unlocked turret, spur gears displaceable relative to one another in the direction of the turret axis are connected to the turret and to the turret slide in a rotationally fixed manner, and a bearing is provided for the turret which in the unlocked state of the latter is free from play.

Abstract: Tool turret for NC automatic lathes comprising a turret body, in which a plurality of tool drive shafts arranged about a turret indexing axis are rotatably mounted, and comprising a main drive shaft coaxial to the turret indexing axis and in drive connection with the tool drive shafts via a miter gear arrangeed in the turret body, as well as a change-over gear for driving the tool drive shafts at different rotational speeds. In order to provide a space-saving and simple construction, the change-over gear is arranged in the turret body between the main drive shaft and the tool drive shaft and is designed as a gear adapted to be changed over only when at a standstill and having no idling state between the drive positions.

Abstract: A lathe comprises two turrets each arranged on a compound slide system. The turrets are mounted on sides of the two compound slide systems facing each other and have indexing axes extending parallel or at a slight incline to the work spindle axis of the lathe. To reduce the danger of collisions between the two turrets and to enable the two turret bodies to be moved close together, the turret body located on the headstock side is smaller and has less stations than the other turret body with the result that the circles described by the tool cutting edges during rotation of the two turrets are smaller in the case of one turret than in the other.

Abstract: A pressure regulator for hydraulically controlled machine tools comprises a first directly controlled three-way pressure-regulating valve with which required work pressure can be set by a machine control system. In addition to a first surface, the control spool is provided with a second surface to which hydraulic fluid under the pressure at the pressure port can be applied by means of an externally controllable valve. This results in an additional force acting upon the control spool in the direction opposite to, or in the direction of, the force exerted by the elastic element on the control spool.

Abstract: Multispindle-automatic turret lathe comprising a spindle support which is rotatable about a central switching or indexing axis and in which are rotatably mounted a number of work spindles each defining one switching or indexing station of the spindle support.In order to enable the tools which are fitted on the turret being precisely measured in that position thereof in which the tools are required to work a measuring station is provided on the spindle support in like geometrical relation to the indexing axis as the workspindles, said measuring station defining a further switching or indexing station of the spindle support.