DE3140797A1 - DEVICE FOR AUTOMATICALLY FEEDING AND REMOVING WORKPIECES FOR CIRCULAR MILLING MACHINES - Google Patents

Description

SAKURAI, LTD., 830, Sukenobu-cho, Hamamatsu, Japan

Device for the automatic feeding and removal of workpieces for rotary milling machines

The invention relates to a rotary table milling machine (also called a rotary milling machine) with a base, a column extending upright from the rear portion of the base, sliding bodies vertically movable thereon, one rotatable on the front portion of the Base mounted turntable with a multitude of circumferentially arranged, upright pins on it its surface and a pair of cutter stud arms, extending from the sliders to a position above the turntable, each support arm has an adjustable cutter and a motor for rotating the cutter.

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Bremen / Bremen Office: Postfach / P. O. Box 10 71 27 Hollcrallec 32, D-2800 Bremen Telephone: (0421) »34 9071 Facsimile / Telecopier: Rank Xerox Telegr. / Cables: Diagram Bremen Telex: 244 958 bopatd

Accounts Bremen:

Bremer Bank, Bremen

(Sort code 290 800 10) 100144900

Deutsche Bank, Bremen

(Sort code 290 700 50) 1112002

PSchA Hamburg

(BLZ 200 100 20) 1260 83-202

Munich Office: Postfach / P. O. Box 14 01 08 Schlotthauerstraße 3, D-8000 Munich 5 Telephone: (089) 65 23 21 Telecop./Telecop .: (089) 2215 69 RX. Telegr. / Cables: Telepatent Munich Telex: 523937 jus d (code: forbo)

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In particular, it is about a device by means of which in such milling machines on an intermittent driven conveyor belt, the workpieces to be processed are automatically transferred to the turntable and workpieces processed at the same time are automatically removed from the turntable, with the feed of the Workpieces to be machined takes place synchronously with the rotation of the turntable.

In conventional machine tools, the workpiece prepared for machining becomes the machining station in this way supplied that a hinged gripping arm grips the prepared workpiece and after a Rotation feeds the workpiece to the processing station, where the gripper arm releases it. A machined workpiece is accordingly fed to the removal station by suitable equipment.

Such gripper arm and unloading arrangements are, however Can only be used where the workpieces are fed to or removed from a stationary table, with rotary table milling machines Such devices cannot be used with a rotating table (rotary milling machines).

Accordingly, it is an object of the present invention to provide an apparatus by means of which a rotary table milling machine Workpieces can be fed in or removed automatically, with the front of the milling machine transported workpieces are to be fed to a predetermined processing station on the turntable and a machined workpiece should be removable from the turntable at the same time.

BOEHMERT & BOEHMERT

Another object of the present invention is to be seen in the fact that the supply and Removal device for rotary milling machines in the Should be able to with synchronized running of the workpiece transport device with the rotation of the turntable, the workpiece to be machined is to be fed precisely to its machining station on the turntable and at the same time a machined workpiece can be removed from the table.

The inventive solution to this problem is characterized by the following components: a horizontally arranged Support plate, which is attached with one end portion to the upper end portion of the column and itself extends forwardly from the column; a rotating main stand that is in the center of the surface of the turntable extends upwards and the lower end is rotatably mounted in the turntable, while its upper End is rotatably mounted in the other end portion of the support plate, with a support arm with inverted U-shape extending horizontally forward from a central portion of the main stand and with a pair of Guide rods are provided, which are spaced parallel between opposite legs of the Support arm extend as well as having a pair of guide wheels mounted on the opposite legs are; a hydraulic cylinder extending between the opposing legs and having a inner piston is provided, which has a piston rod and a pair of connecting means, which along the guide wheels are guided; a workpiece changer which is guided along the guide rods and is connected to the piston by the connecting means, and which is further connected to one with the piston rod associated mounting plate is provided; and one

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Workpiece gripper that is attached to the mounting plate and has a pair of similar workpiece gripping parts which are designed such that when gripping of a workpiece to be machined by one of the workpiece gripping parts the other workpiece gripping part simultaneously removes a machined workpiece.

Advantageous refinements of the invention emerge from the subclaims.

An exemplary embodiment is described in detail below with reference to the drawing. It shows or shows:

Fig. 1 is a side elevation of the device according to the invention for automatic loading and unloading a workpiece;

2 shows a plan view of the device according to the invention;

Figure 3 is a side elevation, on an enlarged scale, of a hydraulic cylinder for actuation the support arm and the workpiece changer;

FIG. 4 shows a plan view according to FIG. 3;

Fig. 5 is a side elevation on an enlarged scale of the workpiece changer;

FIG. 6 shows a front elevation of the workpiece changer from FIG. 5; FIG.

7 shows a view from below of the workpiece gripper of the device according to the invention;

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Figure 8 is a side view of the article of Figure 7; and

Figures 9 to 11 a schematic representation of the different working conditions of the invention Contraption.

The device according to the invention for feeding and removing workpieces is used in rotary milling machines which generally have a base 1, a column 2 extending above the rear section of the base 1 and a turntable 3 which can be operated in a conventional manner (not shown) is rotatably mounted on the front portion of the base 1. The column 2 is provided on opposite sides with embedded guide surfaces 2 ', 2 "in which sliding bodies 4, 4 are received in order to perform a vertical sliding movement. For this purpose, the sliding bodies 4 are in threaded engagement with rotating threaded rods (not shown), which extend vertically in the column, so that when the rotating shaft rotates in one direction or the other by means of suitable drives (not shown) the sliding bodies 4 slide ^{up or down along the guide surfaces 2 1.}

The sliding bodies 4,4 are provided with support arms 39,39 for cutters (or milling heads) and motors, which are connected to one another run at an angle (i.e. not parallel), with the working sections converging. Each of the support arms 39 carries a cutter. 6, which processes the workpiece to be machined held on the turntable 3, as well as a Motor 5 which rotates cutter 6 by means of conventional devices. The cutter 6 is according to the size of the workpiece to be machined along the support arm 39

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A main stand 7 extends vertically upward from the center of the surface of the turntable 3, parallel and at a distance from the column 2. It is rotatably supported at the lower end portion by means of suitable bearings (not shown) in the turntable. The upper end section of the main stand has a reduced diameter at 7 "and is rotatably mounted in an end section of the horizontally extending support plate, the rear end section of which is attached to the upper section of the column 2 = the outermost end section of the part of the main stand 7 shown ^{at 7 1 with} reduced diameter is provided with a U-shaped fork 9. The free end of the fork 9 is connected by means of a pin (not shown) to the horizontal connecting rod 11 which extends from the horizontal hydraulic cylinder 10, which in turn is suitably mounted on the Support plate 8 is supported and driven in a suitable manner (not shown). If the hydraulic cylinder 10 is extended, the main stand 7 is rotated in the manner still to be described.

An inverted U-shaped bracket arm 12 is in a position between the upper and lower end portions of the main stand 7 attached to this and extends from the main stand 7 to the front. Two horizontally extending guide rods 13, 13 "extend parallel at a distance between the opposite legs of the support arm 12. A horizontal hydraulic cylinder 14 extends parallel and at a distance from the guide rods 13, 13 ″ between the opposite ones Legs of the support arm 12 and is with guide wheels 17, 17 "at opposite end portions and one Piston 15 provided inside. The piston 15 is at opposite

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overlying ends with a pair of connectors 16, 16 'connected in the form of wires or ropes are formed and which in turn are guided in the guide wheels 17 and 17 '. At the other End section is the connection to the workpiece changer A, so that when the piston 15 is moved in response on the cylinder 14 (by means of conventional drives) the workpiece changer A is moved along the guide rods 13, 13 '. The rope-shaped connecting devices 16, 16 'are coated in such a way that a circular cross-section is ensured, while opposite end portions of the hydraulic cylinder are suitably sealed to prevent oil leakage. Buffers 18, 18 'and limit switches 19, 20 are on opposite legs of the Support arm 12 mounted. The buffers 18, 18 'and the limit switches 19, 20 are arranged so that when the workpiece changer A arrives at the end of its movement in one direction or the other the buffers 18 or 18 ' be acted upon by the workpiece changer A in order to end the movement, the associated limit switches 19, 20 being actuated.

Opposite sides of the workpiece changer A are provided with adjusting threaded rods 22 and 23, which are extend in opposite directions and align with the limit switches 19, 20 around them to apply.

The workpiece changer A has a main body 24, which is guided along the guide rods 13, 13 ', one Hydraulic cylinder 21, which cooperates with the limit switches 19, 2O, a mounting plate 26, which with the Piston rod 25 of the hydraulic cylinder 21 is connected.

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which extends through the hole 24 ″ in the main body 24 extends below, a pair of parallel and spaced guide rods 27, 27 'attached to an upper Surface of the mounting plate 26 are attached and extend through guide holes 24 ″ in the main body 24 upwards, adjustable upper and lower adjustment parts 28, 28 'the are screwed onto the threaded part of one of the guide rods 27, 27 'to adjust along the guide rods are, limit switches 29,29 ', which are arranged opposite the adjustable setting parts 28, 28' to by this to be acted upon, and a push part 31, which with selected pins 32 cooperating, which are mounted on the upper surface of the turntable 3 and up thereon extend to rotate synchronously with the turntable 3. The mounting plate 26 is provided with a workpiece gripper B, which is mounted thereon and will be described in more detail below. The limit switches 29, 29 ' are mounted on a mounting plate 30 arranged on the main body 24.

The limit switches 29, 29 'act with the on the Main body 24 mounted hydraulic cylinder 21 and arranged in the workpiece gripper B hydraulic cylinders 36, 36 'together. The workpiece gripper B is detachably attached to the mounting plate 26 so that in dependence Workpiece grippers B differing from the type of workpiece to be processed can be used »Is that Workpiece to be machined, for example a cylinder block (FIGS. 7 and 8), the workpiece gripper B has a A pair of similar workpiece gripping devices, one of which is provided on the workpiece feed side of the device, while the other is on the Workpiece removal side is arranged.

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The workpiece gripping unit arranged on the workpiece feed side has a pair of positioning parts 38, 38 " whose outer diameter is essentially the same as the inner diameter of the workpiece to be machined and which extends from the lower surface of the mounting plate extend downwards. A pivot rod 33 is also provided extending from the lower surface of the mounting plate 26 extends downward and to the lower portion of which a workpiece gripping part 34 is attached, as well as a on the rotating rod 33 above the workpiece-gripping part 34 arranged gear 35 which causes the rotation, and a Toothed rack 37, which cooperates with the toothed wheel 35 and the hydraulic cylinder 36 attached to the toothed rack 37 and is responsive to signals from limit switch 29 (see Figures 7 and 8). When the Hydraulic cylinder 36, the rotating rod 33 is rotated in one direction or the other to grip the workpiece to grab or let go. The gripping unit on the The workpiece unloading side is similar to the gripping unit on the workpiece feeding side, which is why the components of the workpiece unloading unit have corresponding reference numerals provided with dashes.

When using the device according to the invention described, it is assumed, for example, that successive Workpieces W, which can for example have the shape of cylinder blocks, on a suitable conventional one Conveyor belt C are brought up, which is driven intermittently and in the vicinity of the turntable passes along the device for feeding or removing the workpieces. The conveyor belt carries with each advance C moves a workpiece W to be machined to the feeding position to the turntable 3 and then stops moving. In a workpiece loading and unloading period, the

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Hydraulic cylinder 14 is applied to the workpiece changer A in one direction or the other along the guide rods 13, 13 'to one of the end positions to move until the workpiece changer strikes one of the buffers 18 or 18 ", depending on the direction of movement, whereupon the buffer stops moving and the threaded rods 22 or 23 to the associated limit switch Hit 19 or 20 to activate them. A short period of time after the Movement of the workpiece changer A, the hydraulic cylinder 21 is set in response to signals from the limit switch 19 or 20 in order to control the Workpiece gripper attached below the mounting plate 26 B along the guide rods 27, 27 'to move.

During the downward movement of the workpiece gripper B, the rotating rods 33 and the associated ones also move Positioning parts 38 'also downwards until they reach the workpiece W to be machined, which is just in front of the base 1 was brought, are adapted. As soon as the one rotating rod 33 and the positioning parts 38 in the workpiece W fit, presses the lower one with the guide rod connected setting part 28 'the associated limit switch 29 ", which then generates signals that the Deactivate hydraulic cylinder 21 and on the other hand the hydraulic cylinder 36,35 'of the workpiece gripper Put B into operation. The hydraulic cylinders 36, 36 'rotate the rotating rods 33, 33' by means of the rack and pinion assemblies 37, 35 or 37 ″, 35 ° by the workpiece gripping part 34 fastened to the rotating rod 33 in a position in which it grips the workpiece W to be machined, while the one on the rotating rod 33 ' attached workpiece gripping part 34 'rotated in the direction in which the workpiece gripping part is the machined

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Workpiece W releases. After a workpiece feed and - Withdrawal period will be appropriate limit switch 41, 41 *, which indicate the clamping or release status and which are aligned with the hydraulic cylinders 36, 36 ', applied to generate signals that causing the hydraulic cylinder 21 on the main body 24 to expand upward. The expansion of the Hydraulic cylinder 21 lifts the workpiece gripper B with the workpiece gripping part 34 on which the to be processed Workpiece W hangs, while the upper adjustment part 28 is suspended during the upward movement of the workpiece gripper B the guide rod 27 the associated limit switch 29 is applied, which in turn generates signals to end the upward movement of the workpiece gripper B. A short period of time after the limit switch 29 has been actuated, the same signal from the limit switch causes the workpiece changer A to start up on the support arm 12, which extends along the guide rods 13, 13 "moved in the direction of the turntable 3 until the workpiece changer A strikes the buffer 18 ', which ends the movement, while at the same time the threaded rod 22 on the workpiece changer A the other Limit switch 20 actuated. Even after the end of the movement of the workpiece changer A, the turntable continues its rotational movement continues, but the rotational speed in relation to workpiece changer A is slow, d. For example, the turntable takes 4 minutes to complete one rotation. The turntable rotates With a stationary workpiece changer A, one of the pins 32 of the turntable 3 strikes against the abutment part 31 (see FIG Fig. 10). The one that hits the limit switch 40 Pin 32 causes the support arm 12 and the workpiece changer A on the support arm 12 to synchronize with the main stand 7 to rotate with the rotation of the turntable 3. During the

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synchronous rotation of the support arm 12 and the workpiece changer A set signals of the limit switch 40 the hydraulic cylinder 21 in operation, which in turn the workpiece gripper B moves down on the mounting plate 26 in order to the newly brought up from the conveyor belt C. To position workpiece W on the location of the turntable 3 from which the previously machined workpiece has been removed, at the same time the positioning part 38 'and the rotating rod 33' of the workpiece gripper B be inserted into the workpiece W being machined, whereupon the lower adjustment part 28 'on the guide rod 27 actuates the limit switch 29 ', which in turn generates signals to limit the downward movement of the workpiece gripper B to finish. A short period of time after the downward movement of workpiece gripper B has finished signals from the limit switch 29 'set the hydraulic cylinders 36, 36 'of the workpiece gripper B in operation, so that the workpiece gripping parts 34, 34' rotate, whereby the workpiece gripping member 34 loosens its gripping force on the workpiece W to be machined while the workpiece is being gripped part 34 'grips the machined workpiece W "= after the loosening or gripping operation of the workpiece gripping parts 34 and 34 'are the hydraulic cylinders 36, 36' of the workpiece gripper B and those connected to them Limit switch 41, 41 'actuated to the hydraulic cylinder 21 to expand slowly, whereupon the workpiece gripping part 34 'also with the machined workpiece W " is moved upward accordingly (see Fig. 11). If the hydraulic cylinder 21 moves upwards, it is released the abutment member 31 attached to the main body 24 from the pin 32 and the support arm supporting the workpiece changer A. 12 is gradually returned to its original position by the hydraulic cylinder articulated on the support plate 8 returned while at the same time the upper setting

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part 28 on the guide rod 27 activates the limit switch, which in turn generates signals to the
To hold hydraulic cylinder 21 in its predetermined, raised position. A short period of time after the upward movement of workpiece gripper B has finished
Signals from the hydraulic cylinder 29 activate the hydraulic cylinder 14 in order to move the workpiece changer A along the guide rods 13, 13 'in the direction of the original feed position, whereupon after the workpiece changer A has returned to the original workpiece Feed position of the threaded rod 23 on the workpiece changer A presses the limit switch 19 on the workpiece feed side to repeat the cycle described above, in which the machined workpiece W ^{1 is released} from the workpiece gripping part 34 ', whereupon the workpiece gripping part 34, the workpiece to be processed W takes ¹ because the inventive device for supplying or removing workpieces for a new operating cycle is ready.

During one cycle of the workpiece loading and unloading device, the machined workpiece W ^{1 is} removed from the turntable 3 and the workpiece W to be machined is fed to a position on the turntable 3 from which the machined workpiece W ^{1 has} previously been removed.

The above-described device according to the invention for automatically feeding and removing workpieces can generally be used with rotary table milling machines which
Usually the following components have: a base 1, a column 2 extending upwards in the rear section of the base 1 with sliding bodies 4, 4 which can slide vertically therein; a turntable 3 rotatable above the front portion
the base 1 is arranged. and support arms 39 on the

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Sliders 4, 4 are attached and each of which carries a workpiece cutter and a motor 5 for rotating the cutter. The device for feeding and removing workpieces has the following components: a main stand 7, which extends upwards in the center of the turntable 3 and is rotatably mounted in the turntable at its lower end; a horizontal support plate 8, one end of which rotatably receives the upper end portion of the main stand and the other end of which is attached to the upper end portion of the column 2, the upper end portion of the main stand having a reduced diameter at 7 'and a fork 9 attached thereto which is connected at the other end to a hydraulic cylinder 10 which is hinged to the support plate 8; an upside-down U-shaped support arm 12 extending forwardly from the main stand 7 and having a pair of parallel, spaced-apart guide rods extending between opposing legs of the support arm; a pair of guide wheels 17, 17 ° attached to. opposite leg portions of the support arm 12 are rotatably mounted; a hydraulic cylinder 14 extending between opposing legs of the support arm; a piston 15 within the hydraulic cylinder 14; a workpiece changer A _f which is guided along the guide rods 13, 13 'and is connected to opposite ends of the piston by means of connecting devices 16, 16 "which are guided via the guide wheels 17, 17"; wherein the workpiece changer A has adjusting threaded rods 22, 23, which extend from the workpiece changer A in different directions, and limit switches 19, 20 at opposite ends of the support arm 12, which can be acted upon by the threaded rods 20, 23

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, the workpiece changer further comprising a main body 24 connected to a hydraulic cylinder 21 is provided, which with the limit switches 19, 20 cooperates; a mounting plate 26 on the piston rod 25 of the hydraulic cylinder 21; a mounting plate 30 for Limit switch on which a pair of limit switches 29, 29 'are mounted, one of which with the hydraulic cylinder 14 cooperates; a vertical Guide rod 27 with a pair of adjustment parts 28, 28 ' which are adjustable along the guide rod 27; a Push part 31, which cooperates with pins 32 on the turntable, to the support arm 12 in synchronism with the rotation of the To rotate turntable 3, wherein a limit switch 40 cooperates with the hydraulic cylinder 21; and one Workpiece gripper B mounted on the mounting plate with workpiece gripper rotating rods 33 and 33 ', which are connected to the limit switches 29 and 29 'cooperate and with workpiece gripping parts 34 and 34' for gripping the to be machined or the machined workpiece are provided with hydraulic cylinders 36 and 36 'for rotating the rotating rods 33 and 33 'and with limit switches 41 and 41 'to indicate the clamping or loosening state, which is connected to the hydraulic cylinder moving the mounting plate and the hydraulic cylinders 36 and 36 'cooperate. Becomes the limit switch connected to the hydraulic cylinder 21 40 actuated, a workpiece to be processed or a processed workpiece is moved horizontally or vertically, wherein the workpiece to be machined is fed to the milling machine or the machined workpiece is fed to the milling machine is removed. Furthermore, the turntable 3 is provided with a plurality of pins 32 which are located on its surface stretch upwards and a certain pin 32 strikes against the workpiece changer A to the turntable

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to rotate synchronously with the support arm of the workpiece changer, whereby the workpiece feed and the workpiece removal takes place precisely in a predetermined position. Furthermore, the operation of the workpiece feed and removal device fully automatic and does not require any manual intervention, using the limit switch for confirmation the clamping and loosening state positively confirm the work carried out.

The in the above description, the claims and Features of the invention disclosed in the drawing can be used both individually and in any combination for the implementation of the invention in its various forms may be essential.

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REFERENCE LIST
(LIST OF RSPSRENCE NUTISRALS)

1 13 ' Base hole • 1 2 Pillar ; 2 'guide surface 2 3 Turntable 4th 16 " Sliding body 4th 5 17 ' engine 5 6th 18 ' Cutter / milling knife 6th 7th Main stand, 7 'position 7th 8th Support plate 8th 9 fork 9 10 cylinder 10 11 Connecting rod 11 12th Beam 12th 13, Guide rod 13th 14th cylinder 14th 15th 2.7 ' Pistons 15th 16 _r 28 ' Connecting device 16 17 r 29 ' Guide wheels 17th 18 buffer 18th 19th Limit switch 19th 20th Limit switch 20th 21st Cylinder (from A) 21st 22nd Threaded rod 22nd 2? Threaded rod 25th 24 Main body (from A); 24 ', 24' ' 24 25th Piston rod (of 21) 25th 26th Mounting plate (from A) 26th 27 r Guide rod 27 28 , Adjustment parts 28 29 _r Limit switch 29 30th Mounting plate 30th

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31 Butt part • 31 32 Pen 32 33, 33 Rotating bar 33 3 ^ 34 Workpiece gripping part 34 35, 35 gear 35 36, 36 cylinder 36 37, 37 ^ Rack 37 38, 38 ' Positioning parts 38 39 Support arm 39 40 Limit switch 40 41 Limit switch 41 A. Workpiece changer A. B. Workpiece gripper B. W, W workpiece W ¹ , W C. Conveyor belt C.

Claims (3)

BOEHMERT & BOEHMERir ".:. - .-.:. SX 2252 Expectations ΠΑ A rotary table milling machine comprising a base, a column extending upright from the rear portion of the base, sliders movable vertically thereon, a rotary table rotatably mounted on the front portion of the base with a plurality of circumferentially disposed upright pins on its surface, and a pair of cutters -Support arms, which extend from the sliders to a position above the turntable, each support arm having an adjustable cutter and a motor for rotating the cutter, characterized by means (Ά, Β) for automatic loading and unloading of workpieces, which essentially have the following components; a horizontally arranged support plate (8) which is fixed at one end portion to the upper end portion of the column (2) and extends forwardly from the column (2); a revolving main stand (7) extending upward in the center of the surface of the turntable (3) and the lower end of which is rotatably supported in the turntable (3) while its upper end is rotatably supported in the other end portion of the support plate (8) , wherein a support arm (12) with an inverted U-shape extends horizontally from a central portion of the main stand (7) forward and having a y / BOEHMERT & BOEHMERT Pair of guide rods (13, 13 ') is provided which extend parallel at a distance between opposite legs of the support arm (12) and with a Pair of guide wheels (17, 17 ') on the opposite Legs are mounted; a hydraulic cylinder (14) located between the opposite Legs extends and is provided with an inner piston (15) which has a piston rod and comprises a pair of connecting devices (16, 16 '), which are guided along the guide wheels (17, 17 '); a workpiece changer (A), which is guided along the guide rods (13, 13 ') and with the piston (15) connected by the connecting devices (16, 16 ") and which is further provided with a mounting plate (26) connected to the piston rod; and one Workpiece gripper (B) which is attached to the mounting plate (26) and a pair of similar workpiece gripping parts (34, 34 '), which are designed such that when gripping a workpiece to be machined (W) through one of the workpiece gripping parts the other workpiece gripping part simultaneously a machined workpiece (W) removed. 2. Turntable milling machine according to claim 1, characterized in that that the support arms (39) for the cutter converge in the direction of the turntable (3). 3. Turntable milling machine according to one of claims 1 or 2, characterized in that the workpiece changer (A) comprises the following components: a main body (24) guided along the guide rods (13, 13 ″); hydraulic cylinder (14) attached to the opposite end sections of the U-shaped support arm (12) Limit switches (19, 20) cooperate; an assembly BOEHMERT & BOEHMERT "::: -. ^-::: - ■ ' - 4-plate (26) j attached to the piston rod (25); a pair of guide rods (27, 27 ')? which differ from the mounting plate (26) extending upward; Adjustment parts (28, 28 ') F which are adjustable on the guide rods (27, 27 ') are arranged; Limit switch (29, 29 "), which are opposite to the adjustment parts (28, 28 ') and are acted upon by them; and a push member (31) with each cooperates with a selected pin (32) of the turntable (3).