WO1997024220A1

WO1997024220A1 - A manipulator device

Info

Publication number: WO1997024220A1
Application number: PCT/SE1996/001656
Authority: WO
Inventors: Josef Zitek; John-Erik Liljengren; Östen JEPPSSON
Original assignee: Ab Volvo
Priority date: 1995-12-27
Filing date: 1996-12-13
Publication date: 1997-07-10
Also published as: BR9612367A; SE505544C2; DE19681722T1; SE9504651L; SE9504651D0

Abstract

The disclosure relates to a manipulator device for realising, in an effector (6), on the one hand a motion pattern (2) with a relatively long, substantially horizontal and rectilinear trajectory (3), and on the other hand a pivoting movement in the effector, where the pivot axis is substantially horizontal and at right angles to the long trajectory. The trajectory (3) has, at each of its two ends, a relatively short, substantially vertical and rectilinear trajectory (4, 5). The manipulator device essentially comprises a linkage system with the effector (6) in a free end thereof, which describes the motion pattern (2). The linkage arm system is drivable under the action of a drive arm (8) pivotally secured (9) in the carrier device (1), an adjustment arm (16) being disposed approximately parallel with the drive arm and, with its one end, pivotally (9) secured in the carrier device a distance from the pivotal anchorage of the drive arm in the carrier device. The pivotal (29) anchorage of the adjustment arm (16) in the carrier device (1) is displaceable in relation to the pivotal (9) anchorage of the drive arm (8) in the carrier device.

Description

A MANIPULATOR DEVICE

TECHNICAL FIELD

The present invention relates to a manipulator device for realising, in an effector, on the one hand a motion pattern with a relatively long, substantially horizontal and rectilinear trajectory which, at each of its two ends, has a relatively short, substantially vertical and rectilinear trajectory, and, on the other hand, a pivotal movement in the effector in which the pivot axis is substantially horizontal and at right angles to the long trajectory, the manipulator device essentially comprising a linkage arm system with the effector in a free end thereof, which describes the motion pattern, the linkage arm system being drivable under the action of a drive arm pivotally secured in a carrier device, an adjustment arm being disposed approximately parallel with the drive arm and, with its one end, pivotally secured in the carrier device a distance from the pivotal anchorage of the drive arm in the carrier device.

BACKGROUND ART

Swedish Patent Specification SE-B-375 724 shows and describes a manipulator device which is constructed for realising, in an effector, a motion pattern with a relatively long, substantially horizontal and rectilinear trajectory which, at each of its both ends, has a relatively short, substantially vertical and rectilinear trajectory.

A manipulator device of this type is employed, for example, for the infeed or discharge of workpieces into and out of a sheet metal working press. The device according to the above-mentioned publication is efficient and expedient as long as the workpiece or the effector need not be sloped (tilted) about a horizontal axis which is substantially at right angles to the long and horizontal trajectory of the motion pattern.

The above-mentioned publication also offers some solution to this problem, but such solution presupposes adjustments which are to be made to the moving effector. If such adjustments are to be made using automatically operating adjustment devices, this entails that the power supply and control/ command signals must be transmitted via the moving linkage system which carries the effector. Furthermore, such a solution entails that the moving mass increases, for which reason a limitation of the work rate of the machinery will be highly probable.

PROBLEM STRUCTURE

The present invention has for its object to design a manipulator device of the type disclosed by way of introduction such that the above-outlined drawbacks are obviated. Thus, the present invention has for its object to realise a manipulator device which permits tilting of the effector without its mass being increased and without any lines, leads or conduits being needed to be led up to the effector. The present invention therefore has for its object to realise a manipulator device in which adjustment of the tilting of the effector may be achieved using fixedly anchored and immobile equipment. The present invention finally relates to a manipulator device which is simple and economical to manufacture, operationally reliable and which permits operation at a high work rate.

SOLUTION

The objects forming the basis of the present invention will be attained if the manipulator device intimated by way of introduction is characterized in that the pivotal anchorage of the adjustment arm in the carrier device is displaceable in relation to the pivotal anchorage of the drive arm in the carrier device.

Further advantages will be attained according to the present invention if the subject matter of the present invention is also given one or more of the characterizing eatures as set forth in appended Claims 2 to 4.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The present invention will now be described in greater detail hereinbelow, with particular reference to the accompanying Drawings. In the accompanying Drawings:

Fig. 1 is a front elevation of a manipulator device;

Fig.2 is a motion pattern which has been realised by the manipulator device according to Fig. 1;

Figs.3-4 show a first embodiment of the present invention;

Fig. 5 shows a first motion pattern which can be realised using the embodiment according to Figs. 3 and 4;

Fig. 6 shows a second motion pattern which can be realised using the embodiment according to Figs. 3 and 4;

Figs 7-8 show a second embodiment of the present invention;

Fig. 9 shows a first motion pattern which can be realised using the embodiment according to Figs. 7 and 8;

Fig. 10 shows a second motion pattern which can be realised using the embodiment according to Figs. 7 and 8;

Figs. 11-14 show a third embodiment of the present invention; and

Fig. 15 is an example of a motion pattern which can be realised using the embodiment of Figs. 11-15.

DESCRIPTION OF PREFERRED EMBODIMENT

In Fig. 1, reference numeral 1 refers to a carrier device which may be supported on a substrate by the intermediary of a frame or the like, but which may also be disposed suspended on, for example, a press. Reference numeral 2 generally relates to a motion pattern which has a relatively long, substantially horizontal and rectilinear trajectory 3 which, at each of its two ends, has a relatively short and substantially vertical and rectilinear trajectory 4 and 5.

The motion pattern 2 is described by an effector 6 which is fixedly secured in the free and movable end of a linkage system 7 which is supported by the carrier device 1. The effector 6 serves for mounting suitable gripping equipment which is intended to grip and retain a workpiece which, for example, is to be lifted out of an open press tool in order to be placed into another open press tool in an adjacent press. The gripping equipment which is disposed on the effector 6 may be of any conventional type whatever and, as a result, is not a germane part of the present invention.

The linkage system 7 is drivable under the action of a pivotal drive arm 8 which is journalled in the carrier device 1 and which is pivotal about a pivot axis 9 under the action of a prime mover disposed in the carrier device. The pivot axis 9 is horizontal and at right angles to the long, horizontal trajectory 3 of the motion pattern 2. The outer end of the drive arm 8 is, via an articulation, pivotally connected to a guide arm 11. The lower end of the guide arm 11 is connected via an articulation 12 to the effector 6. Furthermore, the effector 6 is, via an articulation 13, pivotally connected to an arm 14 whose upper end is, via an articulation 15, connected first to an adjustment arm 16 and secondly to a short arm 17. The adjustment arm 16 has the same effective length as the drive arm 8. The lower portion of the guide arm 11, the effector 6, the arm 14 and the short arm 17 together form a parallelogram arrangement which supports the effector 6. Correspondingly, the drive arm 8, the short arm 17 and the adjustment arm 16 form a parallelogram arrangement which drives the former arrangement.

The upper portion of the guide arm 11 co-operates with guide means 18 having two arcuate, arched guide paths 19 and 20, one on either side of a vertical guide path 21. The guide means 18 includes two upper guides 22 and 23 and a lower guide 24 which together define the three above- mentioned guide paths. The upper end of the guide arm 11 has two rollers 25 and 26 which cooperate with the above-mentioned guides.

The above-described manipulator device operates in the following manner: as long as the guide rollers 25 and 26 are in engagement with the two arcuate, arched guide paths 19 and 20, the effector 6 will move along one of the two short and vertical trajectories 4 or 5. When, on the other hand, the guide rollers 25 and 26 are located in the vertical guide 21, the effector 6 will move along the long, and substantially horizontal trajectory 3.

On pivoting of the drive arm 8 from the position illustrated in Fig. 1 in a counterclockwise direction, the effector 6 will be lifted up to that point where the upper roller 25 enters up into the vertical guide path 21. Thereafter, the upper end of the guide arm 11 will move upwards in the vertical guide path 21 while the drive arm 8 passes the vertical when the two rollers 25 and 26 reach their apex position in the guide path 21. When the drive arm 8 subsequently passes the vertical, the rollers 25 and 26 move downwards along the vertical guide path 21 in order subsequently, in an intermediate position (angled to the left in Fig. 1), to transfer to the arcuate, arched guide path 19 where the effector 6 moves in a downward direction along the shorter trajectory 4. If the drive arm 8 is pivoted in the opposite direction, the same motion pattern will be executed, but in the reverse sense.

Fig. 2 shows the motion pattern which is executed by the device according to Fig. 1 during one working cycle. In Fig. 2, the rods or arms included in the linkage system 7 have been drawn as single lines.

It will be apparent from Fig. 2 that the effector 6 is horizontally directed throughout the entire motion pattern.

In Fig. 1, the lower end of the adjustment arm 16 is shown as secured via an articulation 27 in an arm 28 which projects somewhat out laterally from the carrier device 1 and which may be deemed to constitute a part thereof. The pivot axis 29 of the articulation 27 is parallel with the pivot axis 9 of the drive arm 8.

In Fig. 1, the distance between the pivot axis 9 of the drive arm 8 and the pivot axis 29 of the articulation 27 is as large as the effective length of the short arm 17, i.e. is as large as the distance between the pivot axes of both of the articulations 10 and 15. This implies that the adjustment arm 16 pivots in parallel with the drive arm 8. This state (the adjustment state in the embodiments described below) is a neutral position where the effector 6 is constantly horizontal.

In the neutral position, the pivot axis 29 of the articulation 27 further lies on the long, horizontal trajectory 3 which also applies to the pivot axis 9 of the drive arm 8.

By displacement of the pivot axis 29 of the articulation 27 in relation to the pivot axis 9 of the drive arm 8, it is possible to modify the above-described motion pattern where the effector 6 is constantly horizontal, to altered motion patterns where the effector slopes in one direction or the other about an axis which is substantially horizontal and which is at right angles to the long trajectory 3 of the motion pattern 2 and, as a result, substantially parallel with the two pivot axes 9 and 29. The effector 6 may be inclined or sloped in both directions, and the slope may vary within a complete motion pattern 2.

In a first embodiment, the pivot axis 29 is displaceable in a horizontal direction in relation to the pivot axis 9 of the drive arm 8. Figs. 3 and 4 show how this may be arranged in practice. It will be apparent from Fig.4 that the arm 28 which carries the articulation 27 and interconnects this with the carrier device 1, has a horizontal, elongate aperture 30 in which a journal pin 31 included in the articulation 27 is movably fixed. The journal pin 31 has a transverse, threaded spindle 32 which extends through a slot-shaped aperture in the arm 28 and which is provided with a lock nut 33 for positionally fixing the journal pin in the aperture 30.

Fig. 5 shows a motion pattern which is realised when the pivot axis 29 of the adjustment arm 16 is displaced horizontally away from the pivot axis 9 of the drive arm, i.e. in a direction to the left in Figs. 1 and 5. The pivot axis 29 is now no longer located in the neutral position. It will here be apparent that the effector 6 in the left-hand of the Figure is tilted or pivoted in a clockwise direction while, in the right-hand section of the Figure, it is pivoted in a counterclockwise direction seen from a horizontal reference position. Somewhere along the motion pattern, the effector 6 will therefore pass the horizontal position.

In Fig. 6, the pivot axis 29 of the adjustment arm 16 is displaced in the opposite direction, i.e. closer to the pivot axis of the drive arm 8 than is the case in the neutral position where the effector 6 constantly runs in a horizontal direction. In the adjustment position illustrated in Fig. 6, the effector 6 is, in the left-hand section of the Figure, sloped or tilted in a counterclockwise direction while, in the right-hand section of the Figure, it is tilted in the clockwise direction. Also in this case, the effector 6 will, somewhere along its trajectory, pass the horizontal position.

Figs. 7 and 8 show a second embodiment of the present invention. In this embodiment, the pivot axis 29 of the adjustment arm 16 is displaceable in the vertical direction in relation to the pivot axis 9 of the drive arm 8. This design and constructional solution is similar to that illustrated in Figs. 3 and 4. Thus, the arm 28 has a vertical, elongate aperture 34 in which the journal pin 31 for the articulation 27 of the adjustment arm 16 is displaceable in the vertical direction. Also in this embodiment, the journal pin 31 has a transverse spindle 32 which is provided with a lock nut 33 for fixedly locking the journal pin 31 in the selected adjustment position. For the adjustment proper, use is made of an adjustment screw 35 which extends through the lower end wall to the elongate aperture 34. Also in this embodiment, the transverse spindle 32 extends through a slot-shaped aperture 36 in the arm 28.

Fig. 9 illustrates a motion pattern which is realised using an upward displacement of the pivot axis 29 of the adjustment arm 16 in relation to the neutral position, and thereby also in relation to the pivot axis 9 of the drive arm 8. In this adjustment, the effector 6 is pivoted in a clockwise direction at both ends of the motion pattern.

In Fig. 10, the pivot axis 29 of the adjustment arm 16 is displaced in a direction downwards of the neutral position and thereby also in relation to the pivot axis 9 of the drive arm 8. In this case, the effector 6 is also pivoted in a counterclockwise direction at both ends of the motion pattern 2. Figs. 11-14 show a third embodiment of the present invention in which the pivot axis 29 of the adjustment arm 16 is displaceable both in the vertical and in the horizontal directions in relation to the neutral position and the pivot axis 9 of the drive arm 8.

Also in this embodiment, the articulation 27 of the adjustment arm 16 has a journal pin 31. The journal pin 31 has, like the above-described embodiments, a projecting end portion which is accommodated in an elongate aperture 37 in an adjustment block 38. In the illustrated embodiment, the longitudinal direction of the aperture 37 is disposed vertically. Also in this embodiment, the journal pin 31 is provided with a laterally projecting spindle 32 with a lock nut 33. The arrangement therefore corresponds to the adjustment position in the embodiment according to Figs. 7 and 8, but the elongate aperture is not, in this case, disposed directly in the arm 28 but is instead in the above-mentioned guide block 38.

On its side facing away from the articulation 27, the guide block 38 has an elongate projection or a guide 39 which is accommodated in a corresponding groove 40 in an adjustment plate 41 which is connected with the arm 28 and which, like the arm, may be considered as being included in the carrier device 1. The guide 39 is disposed to be transversely directed, preferably at right angles, to the longitudinal direction of the elongate aperture 37 in the adjustment block and is, thereby, preferably horizontal. The adjustment block 38 is provided with a threaded spindle 42 and a lock nut 43 whereby the adjustment block 38 may be locked in place in relation to the adjustment plate 41 in the selected adjustment position.

As was mentioned above, the embodiment according to Figs. 11-14 permits displacement of the pivot axis 29 of the adjustment arm 16 in both the horizontal and vertical directions in relation to the neutral position, and to the pivot axis 9 of the drive arm 8. This implies that the embodiment according to Figs. 11-14 may realise the motion pattern which is shown in Figs. 5 and 6, and well as in Figs. 9 and 10. The embodiment according to Figs. 11-14 may, in addition, realise the motion pattern in which the motion patterns according to Figs. 5 and 6 may be superposed onto the motion patterns according to Figs. 9 and 10. Fig. 15 shows such a motion pattern as may be conceived as composed of a superposing of Figs. 5 and 9 on one another. In the left-hand half of Fig. 5, the effector is pivoted in a clockwise direction. The same direction of pivot applies to the effector 6 in the left- hand half of Fig. 9. In the left-hand half of Fig. 15, it will be apparent that the effector here displays a considerable pivoting in a clockwise direction, and this pivoting is approximately the sum total of the part-pivotings according to Figs. 5 and 9.

In the right-hand section of Fig. 5, the effector 6 displays a pivoting in a counterclockwise direction, while having, in the right-hand half of Fig. 9, an oppositely directed pivoting. In the right-hand section of Fig. 15, the effector is pivoted in a counterclockwise direction, which is the difference between the pivoting according to Fig. 5 and the oppositely directed pivoting according to Fig. 9. The pivoting of the effector in Fig. 15, right-hand section, is therefore less than the pivoting of the effector in Fig. 5, right-hand section.

Fig. 15 shows only one example of those adjustment possibilities that may be achieved employing the embodiment according to Figs. 11-14. Such motion patterns may, however, be described as superposed combinations of optional pairs of the motion patterns which are shown in Figs. 5, 6 and 9, 10. The size of the pivotings to which the effector 6 is subjected is determined by the size of the displacement of the pivot axis 29 of the adjustment arm 16 from the neutral position, as is illustrated in Figs. 1 and 2.

The present invention has been described in the foregoing in three simple embodiments of manual displacement of the pivot axis 29 of the adjustment arm. Naturally, embodiments also fall within the spirit and scope of the present invention where these manual adjustment possibilities are combined with positional indicators or adjustment scales for the above-mentioned pivot axis so that this may readily be adjusted to a preselected position.

The spirit and scope of the present invention also naturally encompasses such embodiments in which the adjustment of the pivot axis 29 takes place using motor power and in which the position of the pivot axis is sensed by a transducer whose signals are emitted to a central control unit for the device according to the present invention. The present invention should not be considered as restricted to that described above and shown on the Drawings, many modifications being conceivable without departing from the spirit and scope of the appended Claims.

Claims

WHAT IS CLAIMED IS:

1. A manipulator device for realising, in an effector (6), on the one hand a motion pattern (2) with a relatively long, substantially horizontal and rectilinear trajectory (3), which, at each of its two ends, has a relatively short, substantially vertical and rectilinear trajectory (4, 5), and, on the other hand, a pivotal movement in the effector in which the pivot axis is substantially horizontal and at right angles to the long trajectory, the manipulator device essentially comprising a linkage arm system (7) with the effector (6) in a free end thereof, which describes the motion pattern (2), the linkage arm system being drivable under the action of a drive arm (8) pivotally secured (9) in a carrier device (1), an adjustment arm (16) being disposed approximately parallel with the drive arm and, with its one end, pivotally (29) secured in the carrier device a distance from the pivotal anchorage of the drive arm in the carrier device, characterized in that the pivotal (29) anchorage of the adjustment arm (16) in the carrier device (1) is displaceable in relation to the pivotal (9) anchorage of the drive arm (8) in the carrier device.

2. The manipulator device as claimed in Claim 1, characterized in that the anchorage of the adjustment arm (16) in the carrier device (1) is displaceable in the horizontal direction.

3. The manipulator device as claimed in Claim 1, characterized in that the anchorage of the adjustment arm (16) in the carrier device (1) is displaceable in the vertical direction.

4. The manipulator device as claimed in Claim 1, characterized in that the anchorage of the adjustment arm (16) in the carrier device (1) is displaceable in both the horizontal and the vertical directions.