GB2038681A - Turning device in particular for flat work-pieces, which turning device is located between two presses - Google Patents

Abstract

A device for transferring a workpiece 10 between successive work stations 8, 9 and simultaneously inverting it, comprises removal devices 12, 23 for moving the workpiece and workpiece supports 1, 2 which receive the workpiece from the devices 12, 23. Delivery means deliver the workpiece from the support 2 to the work station 9. The supports 1, 2 are arranged for relative movement towards and away from each other on carriages 21, 21 on a frame 6 and the supports 1, 2 are mounted for pivotal movement about respective shafts 3, 5. Workpiece support surfaces of the supports are brought into facing relationship during approach movement of the supports. At the meeting point of the supports the workpiece is engaged by both support surfaces from opposite sides. Upon separation of the supports the workpiece is released by one support surface and held by the other support surface. <IMAGE>

Description

SPECIFICATION Turning device in particular for flat work-pieces, which turning device is located between two presses The invention relates to a turning device in particular for flat work-pieces such as car body parts etc., which turning device is located between two presses, the work-piece being removed from the working space of the preceding press by means of a removal device, supplied to the turning device and after turning about a horizontal axis located at rightangles to the direction of conveyance is supplied by means of an insertion device to the working space of the subsequent press and the turning device consists of two separate support devices, which at their sides remote from each other comprise tilting shafts located at right-angles to the direction of conveyance, the first support device located in the direction of conveyance being able to tilt about a tilting shaft from the horizontal position down into the vertical position and back again and the second support device being able to move in the direction of conveyance and in the opposite direction to the latter and simultaneously being constructed to tilt about its tilting shaft from the vertical position into the horizontal position and back again, according to Patent No. P 27 26 289. 1-14.

In lines of presses, for technical reasons relating to the tools, it is frequently necessary to turn the work-piece over between two presses, for which operation various turning devices have already been proposed.

In a known construction (German Offenlegungsschrift 15 52 592), a belt conveyor is located between the two presses, which conveyor bridges the gap existing between the two preses. In this case, the work-piece is removed by a removal device from the preceding press and deposited on the conveyor belt. Located as a turning device in the central region of the conveyor belt and on both sides of the belt are four-armed arrangements able to rotate about axes located horizontally and at rightangles to the direction of conveyance, the ends of the arms comprising recesses adapted to the shape of the work-piece, in order to receive the work-piece.

After supplying the work-piece to the corresponding recesses in the two four-armed members, the workpiece is tilted by rotating the members through 180 , then the work-piece is deposited on the belt, conveyed further then engaged by the insertion device of the subsequent press and supplied to the working space of the latter.

One drawback of this known construction consists in that a belt conveyor must be provided and if the shape of the work-piece is changed, the star-shaped turning device must be replaced in its entirety.

Furthermore, in the case of work-pieces having a large surface area, a considerable field of traverse exists above the conveying plane, which may lead to difficulties in the arrangement of the feeder located above the conveying plane.

The same drawback existed in a further known turning device (German Offenlegungsschrift 21 12 590), in which the work-piece is engaged by means ofgrippertongs and likewise tilted through 180 above the conveying plane.

According to another proposal (German Offenlegungsschrift 25 44 203) the work-piece is likewise removed by means of a removal device from the preceding press and then engaged by two gripper tongs constructed as supports and acting at rightangles to the direction of conveyance and then tilted through 180 about the longitudinal axes of the grippers and subsequently engaged by the insertion device of the following press and inserted in the latter.

This device has the drawback that in practice it is only possible to turn small work-pieces with the latter. Furthermore, with tongs, it is not possible to turn work-pieces having a large surface area, for example two connected car doors, which do not have adequate inherent stability. In this case, in practice, the work-piece would hang between the two tongs. It is a further drawback that during the turning operation, the work-piece swings upwards with half the extent of the latter above the conveying plane, due to which the vertical stroke of the removal device must be correspondingly large.

This is where the idea of the main patent is introduced, the object of which is to provide a turning device, the kinematics of which are selected in a different manner, which has a simpler construction and with which the afore-mentioned drawbacks are obviated.

This was achieved according to the main patent due to the fact that the turning device consists of two separate support devices, which at their sides remote from each other comprise tilting shafts located at right-angles to the direction of conveyance, the first support device located in the direction of conveyance being able to tilt about a stationary tilting shaft from the horizontal position down into the vertical position and back again and the second support device being able to move in the direction of conveyance and in the opposite direction to the latter and is simultaneously constructed to tilt about its tilting shaft from the vertical position into the horizontal position and back again.

The advantage of this invention according to the main patent is to be seen in that the actual tilting operation by means of two separate individual devices is divided into two separate movements through 90 and in this way the work-piece is not swung upwards substantially above the conveying plane. The use of the device has proved particularly advantageous in the case of work-pieces having a large surface area, which have no adequate inherent stability.

This is where the present invention is brought into action and the object of the latter is to improve the turning device according to the main patent to the effect that with the latter, the conveying distance between two presses covered per unit time is increased.

This is achieved according to the present development, in a turning device of the aforedescribed construction, due to the fact that in addition to its ability to tilt, the first support device is likewise constructed to move in the direction of conveyance and in the opposite direction to the latter.

Thus, in practice, since with this construction, the first support device is already moved in the direction of the second support device, during the introductory stage for the turning operation, the second support device can adopt a different rear position so that it simultaneously acts in the manner of a further support device serving as an orientation station, which had to be provided by way of addition according to the main patent, between the second support device and the subsequent press.

In this case, the feeder also provided for intermediate conveyance in the main patent can also be dispensed with, which feeder carried out an intermediate transfer from the second support device to the orientation station. This means that only an insertion device is provided, which introduces the work-piece directly from the second support device into the working space of the subsequent press. A further result of this is that the insertion device has only one arm and thus only a single work-piece must be transported, which necessarily leads to a reduction in the masses to be moved. Due to this, it is possible to increase the number of strokes of the press considerably.

The invention is described in detail hereafter with reference to the drawings which show one embodiment partly diagrammatically: Figure 1 to 3 show two presses in a diagrammatic side view, illustrating various positions of the turning device constructed according to the invention, in which case identical parts corresponding to the main patent are provided with identical reference numerals.

In the figures of the accompanying drawings, for the sake of simplicity, only two presses 8 and 9 from the line of presses are illustrated, the number of which presses is optional. In this case, as the top press, the press 8 may be a drawing press for example, in which the work-piece 10 introduced obtains a first basic shape by a drawing operation, whereas the subsequent presses continue the machining of the work-piece 10. As can be seen, in the example illustrated, the work-piece must be turned between the presses 8 and 9.

The two support devices 1 and 2 are located in a common frame 6 situated between the presses 8 and 9. The support device 1 is constructed to pivot downwards through at least 90 about a tilting shaft 3 and the support device 2 is constructed to tilt downwards about a tilting shaft 5. In addition, both support devices 1 and 2 are mounted to move in carriages 21 and 22 in the frame 6 in the direction of conveyance 4 and in the opposite direction to the latter.

The actual operation of the turning device is described in detail with reference to Figures 1 to 3.

In Figure 1,the machining operation in the presses 8 and 9 is terminated and the removal devices 12 and 23 associated with the presses 8 and 9 are introduced into the working spaces 24 and 25 of the presses 8 and 9 and have engaged the work-pieces 10 with suction members 16 for example.

After the work-pieces 10 are lifted, they are removed from the work spaces. In this case, as can be seen from Figure 2, the work-piece 10 removed from the work space 24 of the press 8 by the removal device 12 is placed on the support device 1, whereas the workpiece 10 previously placed on the support device 2 is introduced by means of an insertion device 17 into the working space 25 of the press 9 and deposited at this point.

The actual turning operation of the work-piece located on the support device 1 now begins. The entire sequence is illustrated in dot-dash lines in Figure 1, in which case the central position is shown in full line in Figure 3. The two support devices 1 and 2 move towards each other and simultaneously tilt downwards through 90 about their tilting shafts 3 and 5 and in the example illustrated, come into contact with each other approximately after covering an equal distance, the actual transfer of the workpiece 10 from the support device 1 to the support device 2 taking place in the position shown in full line according to Figure 3. Subsequently, the entire sequence of movements is reversed, in which case the work-piece 10 is conveyed by the support device 2 into the position shown in full line in Figure 1.

Claims (5)

1. A device for transferring a workpiece between successive work stations and simultaneously inverting it, comprising means for removing the workpiece from one work station, a first workpiece support adapted to receive the workpiece from the removing means, a second workpiece support, and delivery means for delivering the workpiece from the second support to the other work station, the first and second supports being arranged for relative movement towards and away from each other on a conveying path running between the work stations and being mounted for pivotal movement about respective axes at right angles to the conveying path, whereby, in use, workpiece support surfaces of the supports are brought into facing relationship during approach movement of the supports such that at the meeting point of the supports the workpiece is engaged by both support surface from opposite sides and upon separation of the supports the workpiece is released by one support surface and picked up by the other support surface.

2. A device as claimed in claim 1, wherein both supports are movable along the conveying path and the meeting point of the supports is intermediate the ends of the conveying path.

3. A device as claimed in claim 1 or 2, wherein the conveying path is horizontal and the support surface of each support is pivotal from a horizontal position for cooperation with the respective removing or delivery means into a vertical position at said meeting point.

4. A device as claimed in any one of the preceding claims, wherein each support comprises a platform providing said support surface, and a support arm fixed at one end to the underside of the platform and pivotally mounted at its other end on a carriage movable along the conveying path.

5. A device for transferring a workpiece between successive work stations and simultaneously inverting it, substantially as herein described with reference to and as illustrated in the accompanying drawings.