GB2130515A - A device for moving workpieces in production machines such as blanking presses - Google Patents

Abstract

The apparatus comprises an elongate base 1 in the form of a narrow beam on which a carrier strip 14 is guided, for reciprocating movement on longitudinal guides 10 by means of a slide 12, 13 and acts as a carrier for gripper elements, e.g. suction cups or retaining magnets. The drive mechanism includes two upright reversing wheels 6, 7 and a toothed belt (9, Fig. 2) which is guided thereon and connected by plate 13 to the carrier strip 14. The reversing wheels 7 is connected to a drive motor (8, Fig. 2) having a flange mounted on the base 1. The drive motor is preferably an electro-hydraulic rotation amplifier consisting of a set-value transmitter, a control valve and a hydromotor. The carrier may be a flat or profiled (L, U) strip and carry the magnets etc by means of an angle arm; a second arm may be provided for removing blocks. The apparatus can be used in production machines with restricted space conditions in which it is difficult or impossible to use conventional devices. <IMAGE>

Description

SPECIFICATION A device for moving workpieces in production machines such as blanking presses or the like This invention relates to apparatus for moving workpieces in production machines such as blanking presses or the like, comprising a carrier which is movable between two end positions by means of a drive and has means for engaging and depositing the workpieces.

For blanking presses and other production machines it is known for the workpieces to be mechanically introduced into the machine by special devices and, if required, removed therefrom after machining. Conventional devices for this purpose, i.e. for introducing the workpieces, are usually provided with an insertion arm which for the purpose of moving the workpieces performs a rocking movement about a vertical axis. A working movement of this kind, however, requires a relatively large amount of free space between the place where the workpieces are to be deposited and the production machine. As a result, there are considerable limitations on the use of such devices, which are often impossible to use.

This applies particularly to double column blanking presses in which the column spacing is relatively small.

The object of the invention is to provide a device for moving workpieces in production machines which is also suitable for restricted space conditions, offers considerable accuracy in respect of positioning, and is suitable for multiple use.

Broadly stated the invention consists in apparatus for moving workpieces in production machines such as blanking presses or the like, comprising an elongate beam on which a carrier is guided for reciprocating longitudinal movement between two end positions, the carrier being arranged to support work feed elements such as suction cups or retaining magnets, and a flexible tension ele ment connected to the carrier and running over a reversing wheel at each end of the beam, one of the reversing wheels being connected to a drive motor mounted on the beam.

Preferably the beam is in the form of a housing of substantially rectangular cross-section and of narrow width in relation to its height, the longitudinal guides and the revers ing wheels being positioned inside the hous ing.

Preferably also the carrier is positioned above the beam and at a short parallel distance therefrom. It may consist of an angle section member or of some other suitable section.

According to a preferred feature of the invention, the tension element is a toothed belt which ensures slip-free connection between the two reversing wheels. In this way it is possible to take off from that reversing wheel not directly connected to the drive motor a torsion drive for any auxiliary units.

According to another preferred feature, two guide rods are positioned between the top and bottom runs of the toothed belt in parallel spaced relationship one above the other and centrally to the plane of the top and bottom runs, and are secured in the housing at their ends, and a common sliding member is guided for reciprocating movement on said guide rods and serves for fixing and mounting the carrier strip and is connected to the top run of the toothed belt, e.g. by a clamp connection.

Advantageously the drive motor has a flange mounted on the beam in axial alignment with one of the reversing wheels. A particularly suitable drive motor is an electrohydraulic rotation amplifier, consisting of a set-value transmitter, a control valve, and a hydromotor.

According to another aspect of the invention the shaft of the non-driven reversing wheel projects externally and is arranged as a drive shaft for other auxiliary devices.

The narrow construction in the form of a beam and the linear working movement offer the great advantage that this device can also be used in production machines with restricted space conditions, in which it is difficult or impossible to use conventional devices.

In addition, the workpieces can be introduced and removed by means of a single device.

Where necessary, a number of gripper elements can be disposed on the movable carrier strip. The use of an electro-hydraulic rotation amplifier as a drive guarantees a high power amplification and great accuracy in respect of positioning. The device can also be used as a drive for auxiliary units, e.g. to drive a workpiece magazine. Numerous applications and possible combinations can be obtained with a single device and particularly in conjunction with a second similar device.

The invention may be performed in various ways and several embodiments will now be described by way of example with reference to the accompanying diagrammatic drawings, in which: Figure 1 is a longitudinal section of the device in the plane of the reversing wheels, Figure 2 is a plan view of the device without the carrier strip, Figure 3 is a part elevation of a double column blanking press in which a device according to Figs. 1 and 2 for introducing workpieces is disposed in the column open ing.

Figure 4 is a plan view of the arrangement shown in Fig. 3, Figure 5 is a corresponding illustration to Fig. 3 showing the use of a device enabling the workpieces to be introduced and removed, Figure 6 is a plan view of the arrangement shown in Fig. 5, Figure 7 is a partial elevation of a double column blanking press in which two devices for inserting two workpieces each are disposed inside the column opening.

Figure 8 is a plan view of the arrangement shown in Fig. 7.

The apparatus illustrated in Figs. 1 and 2 comprises a base 1 in the form of a beam, in which two parallel side members 2 are connected by suitable intermediate members 3 to form a housing of substantially rectangular cross-section. This housing is relatively narrow in relation to its height. As shown in Fig. 1 the bottom corners can be bevelled.

Near each end of the base 1 a reversing wheel 6,7 is disposed on a shaft 4,5 so as to rotate therewith. Each wheel is positioned between the two side parts 2, and mounted in bearings in the side parts 2 by means of the shafts 4,5. The free ends of the shafts 4,5 project externall through the bearings. The shaft 5 is connected on one side to a drive motor 8 having a flange secured to the side part 2. The two reversing wheels 6,7 are arranged to be engaged by a peripheral toothed belt 9 which connects the reversing wheels 6,7 so as to form a slip-free transmission.

Two guide rods 10 are positioned in the space between the top and bottom runs of the toothed belt 9, and parallel thereto and centrally in relation to the plane thereof. At their ends the rods are rigidly secured to crossmembers 11 extending from the side members 2. A slider 12 is guided for reciprocation on the guide rods 10 and at its upper end has a clamping and retaining plate 13 releasably secured by means of screws or the like. By means of the clamping and retaining plate 13 the top run of the toothed belt 9 is clamped to the slider 12, so that the latter can reciprocate between its two end positions by means of the toothed belt 9.

The clamping and retaining plate 13 is also used to secure a carrier strip 13 releasably secured substantially in the centre to the clamping and retaining plate 13 by means of screws or the like and extending parallel to the base 1 at the top thereof. In this illustrated example the carrier strip 14 consists of an angle section, but it may be of other crosssectional shape, e.g. a flat strip or a Usection.

All the mechanism for moving the carrier strip 14 is accommodated inside the base 1.

The parts of this mechanism such as the sliding guide and toothed belt drive are so designed that the base including the movable carrier strip is very narrow. In a practical embodiment suitable for numerous applications the width is about 60 mm. The linearly movable carrier strip 14 serves as a carrier for gripper elements, e.g. suction cups or other penumatically or hydraulically actuated elements, or retaining magnets directly or indirectly secured to the carrier strip in a suitable way.

The drive motor 8 has a mounting flange by which it is secured to the base 1 on the outside thereof. An electro-hydraulic rotation amplifier can advantageously be used to control the motor, consisting of a set-value transmitter, a control valve, and a hydromotor. The set-value is introduced via a lowpower stepping motor, the actual-value of the rotation movement of the hydromotor is signalled via a measuring screw spindle situated between the hydromotor and the control valve. A rotation amplifier of this kind is known per se. Its advantages are high torques, high dynamics and high accuracy in respect of positioning. It is also possible for auxiliary units, e.g. a parts magazine, to be driven without difficulty.

Figs. 3 to 8 show different possible applications of the invention to a double column blanking press by way of example. In every case the apparatus extends through the column opening 15,22 of the blanking press 16,23 level with the press table 17, on which the bottom tool rests.

As shown in Figs. 3 to 6, a magazine 18 from which the workpieces to be machined are removed, is positioned in front of the blanking press 16. The workpieces in this case are circular discs 19 stacked one above the other. The magazine 18 is connected for transmission to the shaft 4 of the reversing wheel 6 of the device A, as previously described.

An angle arm 20 is secured to the carrier strip 14 and carries a gripper element (not shown), e.g. a suction cup, for engaging the workpieces 19. The workpiece 1 9 taken from the magazine 1 8 is fed to the blanking press 1 6 by an appropriate movement of the carrier strip 14 and deposited on the bottom tool.

The magazine 18 is actuated simultaneously with the working or return movement of the carrier strip 14 so that the next workpiece is brought into the pick-up position.

The example illustrated in Figs. 5 and 6 differs from that shown in Figs. 3 and 4 in that another angle arm 21 is secured to the other end of the carrier strip 14 of the device A and bears a gripper element (not shown) for removing the finished workpiece.

In the example shown in Figs. 7 and 8, two devices A and B are arranged in reversely identical relationship inside the opening 22 between the columns of the blanking press 23. The construction of these devices is as in the example illustrated in Figs. 3 and 4, i.e.

they are used only to introduce the workpieces. In this blanking press two workpieces 19 are introduced and machined simultaneously. Accordingly two magazines 18 are disposed in front of the column. Each of the two magazines 18 is connected for transmission to the associated device A,B thus actuating the associated magazine 18.

As shown in Fig. 8, the two devices A and B are driven by a single drive motor 8. A connecting shaft 24 is provided for transmitting the rotary movement to the adjacent device B and interconnects the free ends of the shafts of the opposite reversing wheels. The shaft of the reversing wheel of device B may also be extended so that it can be directly coupled to the end of the shaft 5 of the reversing wheel 7. Connecting the two devices A and B for joint transmission guarantees that all movements of the two carrier strips 14 and the drives for the magazines 18 are synchronized.

As in the example shown in Figs. 5 and 6, additional angle arms for removing the workpieces after the machining can be disposed on the carrier strips 14 in the embodiment shown in Figs. 7 and 8.

Claims (9)

1. Apparatus for moving workpieces in production machines such as blanking presses or the like, comprising an elongate beam on which a carrier is guided for reciprocating longitudinal movement between two end positions, the carrier being arranged to support work feed elements such as suction cups or retaining magnets, and a flexible-tension element connected to the carrier and running over a reversing wheel at each end of the beam, one of the reversing wheels being connected to a drive motor mounted on the beam.

2. Apparatus according to Claim 1, in which the base is in the form of a housing of substantially rectangular cross-section and of narrow width in relation to its height, longitudinal guides for the carrier and the reversing wheels being positioned inside the housing.

3. Apparatus according to Claim 1 or Claim 2, in which the carrier extends parallel to and above the beam.

4. Apparatus according to any one of Claims 1 to 3, in which the tension element is a toothed belt.

5. Apparatus according to any of the preceding claims, including two guide rods positioned between the top and bottom runs of the tension element in parallel spaced relationship one above the other and centrally to the plane of the top and bottom runs, the rods being secured to the beam at their ends, and a common sliding member is guided for reciprocating movement on said guide rods and is connected to the carrier and also to the top run of the tension element.

6. Apparatus according to any one of Claims 1 to 5, in which the reversing wheels are mounted on bearing shafts which project transversely from the beam and are arranged as drive shafts for connection to auxiliary units.

7. Apparatus according to any one of claims 1 to 6, in which the drive motor has a flange by which it is mounted on the beam coaxially with one of the reversing wheels.

8. Apparatus according to any of the preceding claims, in which the drive motor is an electro-hydraulic rotation amplifier consisting of a set-value transmitter, a control valve and a hydromotor.

9. Apparatus for transporting workpieces in a production machine, substantially in any of the forms described herein.