FI81982C - Adaptation element for a robot - Google Patents

Description

81982

ROBOT FLEXIBLE ELEMENT - ADAPTIONSELEMENT FOR ROBOT

The present invention relates to a resilient element to be mounted between the wrist and gripper of a robot or manipulator, the resilient element consisting of a body part attached to the robot or manipulator wrist, a vertical resilient part mounted on the body part and the wrist axis, and an il-10 low-bearing horizontal spring part to be attached to the gripper, the means of which are mounted on the bearing of the spring parts in order to compensate for possible positioning and positioning errors of the robot or manipulator in at least two dimensions.

15 Robotic part handling, and especially assembly, often has difficulty achieving adequate positioning accuracy. In production use, the positioning accuracy is affected by the wear of the equipment (robot, gripper, fasteners) and the shape variations of the parts to be processed.

20

In order to compensate for positioning inaccuracies, a so-called RCC (Remote Clear Compliance) element, which is installed between the wrist of the robot and the gripper. The disadvantage of an RCC can only be considered to be its suitability for handling a particular body 25, since the point at which elasticity occurs is a constant specific to each element.

The so-called active positioning error correction element can be considered to be a force and / or torque-30 sensor installed in the manner of an RCC, which measures the forces and moments generated during the installation work and is able to provide the robot with information on necessary repairs. The disadvantage of a force or torque sensor is the high cost, large size and its suitability only for robots that are ready for external control connection.

The present invention relates to a resilient error-correcting resilient element to be mounted between the wrist and gripper of a robot or manipulator, which does not have the above-mentioned limitations and which is thus universal, piece-independent, enables versatile sensing and is inexpensive. The elastic element according to the invention is thus characterized in that one or more sensors are mounted between the vertical elastic part and the body part, which register the contact and / or positioning forces along the axis of the wrist.

Other preferred embodiments of the invention are characterized by what is set out in the claims below.

15

The invention will now be described in more detail by way of example with reference to the accompanying drawings, in which

Figure 1 shows a side view and section through of a resilient element according to the invention,

Figure 2 shows a top view of a resilient element according to the invention, Figure 3 shows a resilient element according to the invention mounted on the arm of a robot.

In Fig. 1, the main parts of the resilient element 3 according to the invention consist of a body part 30 4 to be fastened to the robot's wrist 1, a vertically mounted two-part vertical resilient part 5a and 5b and a horizontally mounted frame-like horizontal resilient part 6 on the lower surface.

35 The horizontal spring part 6 is hovered by means of compressed air supplied to the duct systems 7a and 7b, whereby the horizontal spring part moves

II

3 81982 between the plates 5a, 5b of the vertical elastic part on the upper and lower air cushion. The air cushion bearing allows smooth movement in the X and Y directions (e.g. ± 2 mm), as well as around the vertical axis Z (e.g. 5 *), ensuring flexible gripping of the gripper, even if small positioning errors occur during part handling. Thus, stresses, knocks, and infection failures otherwise caused by errors can be avoided to a certain extent. In addition, the spring element 3 according to the invention is independent of the shape, weight and material of the body to be treated.

In order to self-center the horizontal resilient part 6 with respect to the Z-axis, the vertical resilient part 5a and the horizontal resilient part 6 are provided with two pairs of mutually attracting permanent magnet poles 8 and 9 (Fig. 2). The centering force is adjusted to suit by changing the distance between the magnets 8.9.

The vertical resilient part 5a, 5b is mounted on four linear bearings 10, on the pins of which it can move in a vertical direction. The range of movement of the vertical elastic part is about 2 mm, and its operation is based on the fact that when the gripper of the robot grips something, the vertical elastic part allows a small compensating movement towards the wrist 1 of the robot, e.g. due to distance error.

25

During the generally very fast working movements of the robots, the horizontal spring part 6 is usually locked in a certain position to avoid the oscillation of the gripper due to the rapid movements. Locking of the horizontal spring part 6 in its central position ta-30 takes place by means of small compressed air boxes 14 and conical pins 15. When the compressed air boxes are activated, the conical pins protrude into the conical centering recesses at the ends of the horizontal spring part, whereby the horizontal spring part is mechanically forced into its central position. According to the invention, the locking of the horizontal resilient part 6 to a certain non-central or random position takes place by applying a vacuum 4 81 982 between the plates 5a, 5b of the vertical resilient part along the ductwork 7a, 7b instead of overpressure. Due to the vacuum, the suction acting on both sides of the horizontal spring part 6 effectively locks the part in place.

5

In general, it is important to know the exact time when the robot gripper grips the workpiece, because the horizontal spring part must then be unlocked in order for it to function. This moment can be detected by providing the space 12 between the part 5a and the body 4 with one or more sensors 13 sensing mounting and / or contact forces. On / off detection of the contact current already tells the exact time of the robot's grip, and provides a horizontal resilient airbag. The detection of the installation force, which occurs when the vertical resilient part slides along the pins 11 in Fig. 1 upwards while compressing the installation force against the sensor 13, can be used for fault monitoring, feedback of the active positioning error correction system or temporarily in the installation phase.

Figure 2 shows a top view of the elastic element according to Figure 1. It distinguishes between the location of the two pairs of permanent magnets 8,9 and the shape of the duct 7a used for the air cushion bearing, which terminates in the circular nozzles forming the air cushion.

Figure 3 shows a resilient element 3 according to the invention mounted on a robot arm 1. The figure also shows the vertical resilient part 16 and the horizontal resilient part 17 and the robot gripper 18 attached thereto. Thus, it can be seen that the movements of the gripper 18 are immediately transmitted to the horizontal resilient part 17 and the vertical movements therethrough to the vertical resilient part 16.

35 5 81982

It will be clear to a person skilled in the art that the various embodiments of the invention are not limited to the example given above, but may vary within the scope of the claims below. Thus, the terms robot wrist and robot gripper 5 are generic terms for any robot arm or holder structure and tools that perform part handling, respectively.

Claims (4)

A flexible element for being positioned between a handlove and a gripper by a robot or manipulator, the flexible element consisting of a stem part (4) to be attached to the robot or manipulator handlove, one at the stem part and in the direction of the shaft of the handloom stored vertical flexible part (5a, 5b; 16), and an air-stored horizontal flexible part (6; 17) in the transverse plane of the shaft of the wrist to be fixed to the robot or manipulator's grippers, whereby possible positioning or placement errors of the robot or manipulator with arranged clearance for said flexible parts can be compensated at least in two dimensions, characterized in that one or more sensors (13) are registered between (12) the vertical flexible part (5a, 5b) and the stem part (4) and / or placement forces in the direction of the axis of the hand (1). Flexible element according to claim 1, characterized in that it exists for centering the horizontal plane of the horizontal flexible part (6) two with respect to the center axis of the horizontal flexible part symmetrically positioned: permanent magnet pairs (8,9) in the horizontal flexible part the part :: and in the vertical flexible part (5a). 25 Flexible element according to claim 1 or 2, characterized in that the horizontal flexible part (6) can be licensed in any position by means of negative pressure which is passed through channels (7a, 7b). 30 Flexible element according to any of claims 1-3, characterized in that it is connected to the vertical "*" flexible part (5a, 5b) of air cylinders (6,9), with which locking pins (15) can be pushed to two conical recesses in it. The ends of the horizontal flexible part (6) to guide it *. horizontal flexible part (6) in its center position. «» • · »