Advancing mechanism for a series of fixtures having collets for workpieces are actuated by a fluid actuated double-acting cylinder to lock and unlock the collet. A driven rotatable table has a plurality of equally spaced fixtures mounted thereon which are advanced seriatim to a plurality of machining stations where work is performed thereon. Each advancement moves a fixture to the unloading and loading station where the collet is released, the finished workpiece removed and a workpiece to be machined placed within the collet. The double-acting cylinder was actuated by the fluid to release the collet and after a workpiece was placed therein a reversal of the fluid clamped the collet in secured position. The collet is locked and unlocked by the operation of a transverse pin in a sloping slot in a sleeve which is advanced over the collet to move the sections of the head into clamped position to hold the workpiece. The table is driven to advance the collets the distance the fixtures are spaced apart and are accurately located by a shot pin which enters a hole in the table. Thereafter a dwell time is provided during which work is performed on the workpieces located at each of the stations. Any number of stations may be provided depending upon the number of machining operations to be performed.

A high-production, precision machine tool has means for varying the feed rate of the tool during the actual machining of each workpiece. The means comprise a plurality of program cams disposed on the camshaft of the machine tool for selecting the appropriate feed rate at the desired time during the machining operation. The camshaft is rotated by a permanent magnet D.C. motor, and as the camshaft rotates, the program cams, in turn, trip a plurality of switches to gate one of several predetermined voltage signals representative of the desired motor speeds to a comparator which compares the gated signal with the output of a tachometer measuring the actual motor speed. The difference, a voltage signal representative of the correction to be made to the motor, is applied to a silicon controlled rectifier firing circuit which selectively fires an SCR network, generating a shaped pulse to provide a controlled voltage input to the motor, thereby selectively controlling its speed.

This automatic machine is intended for machining workpieces in order to reduce their want-of-balance, notably in the case of small or medium series of rotary parts. This machine, adapted to balance dynamically these parts, comprises a measuring station and a plurality of machining stations disposed on a common circle, and a central rotary device having a vertical axis and disposed centrally of said stations for transferring simultaneously all the parts from one station to the next station in the same direction of rotation.

A multiple station drilling apparatus is used for performing a large number of repetitive but variable machining operations, and includes a turntable having a plurality of workpiece holding fixtures distributed in spaced relation around its periphery, a plurality of tool supports mounted around and outward of the periphery to provide a sequence of machining stations, a load/unload station for the mounting of workpieces on the fixtures and their removal therefrom, and a motor for driving the turntable in an indexing fashion to bring workpieces held in the fixtures successively into registry with the machining stations. Each tool support includes at least one X-Y positioner which in turn supports a machining tool such as a reciprocating drill. Each machining tool, its associated X-Y positioner, and the turntable are actuated by a control such that the turntables index the workpieces to successive machining stations, and at each station, the X-Y positioners repeatedly position their respective machining tools independently of each other such that each machining tool performs a series of repetitive machining operations within a separate predetermined area on the workpiece.

A device for machining a plurality of workpieces. The device having a plurality of identical independent machining assemblies attached on a rotating carousel plate such that one operator can unload and load a workpiece at one machining assembly while the other machining assemblies are machining the workpiece therein such that when a machining assembly returns from rotation on the carousel plate it is finished machining.