SU841962A1 - Industrial robot gripper - Google Patents

Description

(54) CAPTURE OF INDUSTRIAL ROBOT

. . ,one

The invention relates to mechanical engineering and is intended for use in industrial robots used to carry out lifting, assembly, assembly and technological operations, as well as in remote manipulators operating in radioactive radiation zones in space.

Known capture handle, soda, holding body, clamping jaws, drive and summing mechanism 1.

A disadvantage of the known device is that its design does not allow making a correction to the manipulator operation program, which reduces the reliability of the latter, especially for large values of deviations of the position of the object to be manipulated from the capture axis.

The purpose of the invention is to provide reliable, inaccurately oriented objects relative to the clamping jaws.

The goal is achieved in that the gripper is equipped with a feedback sensor, and the summing mechanism is made in the form of a rack-and-pinion gear transmission, the feedback sensor being connected to the gear wheel of this gear.

In addition, the drive is made in the form of a pneumatic cylinder of one-sided operation I, a rack and pinion gear is located in the body of the pneumatic cylinder, and the gear wheel of this transmission is kinematically connected with the piston of the pneumatic cylinder.

FIG. 1 shows the capture of an industrial robot, side view, section; in fig. 2 shows section A-A in FIG. one; in fig. 3 is a diagram of capturing objects asymmetrically arranged with respect to the gripping jaws; in fig. 4 is a diagram of another variant of capturing objects.

The capture of an industrial robot consists of a body ,, clamping jaws 2 and 3, connected to body 1 by means of symmetric articulated linkages made of leading links 4 and 5 of the link. Leading link 4 of articulated linkages by means of intermediate levers 6 are connected to two rods 7 and 8, concentrically arranged relative to each other with the possibility of movement, at the ends of which gear racks 9 and 10 are cut. The outer rod 7 enters the power piston 1 with the possibility of movement in it. The gear wheel 12, which is included

in engagement with the toothed racks 9 and 10, on bearings 13 is fixed in the housing of the power piston 11 and kinematically soy; Ino with sensor 14 feedback. A drive, e.g., a single-sided non-cylinder 15, is secured by the front wall 16 to the capture body 1 of the industrial robot. In its back cover 17 there is an opening for supplying the harness 18 to the feedback sensor 14. A return spring .19 is installed between the rear cover 17 and the power piston 11. In the housing of the pneumatic cylinder 15 there is a nozzle 20 for supplying compressed air into the working cavity.

The capture of an industrial robot works as follows.

Compressed air entering through the nozzle 20 into the working cavity of the pneumatic cylinder acts on the piston 11, which makes a working stroke, simultaneously compressing the return spring 19. The gear wheel 12, moving together with the piston 11, acts with equal force on the gear racks 9 and 10. This force is transmitted through the rods 7 and 8 and the intermediate levers 6 to the leading links 4 of the hinge linkages, which with the pins 5 and the clamping jaws 2 and 3 form the mechanisms of the parallelogram m and due to which the parallel movement of the clamping jaws is ensured. approx 2 and 3 gripping industrial robota.- -. ..,

If there is no object between lips 2 and 3, they are compressed unhindered; the income to the end position is stopped by the signal of the limit switches (not shown) of the limit position of the clamping jaws.

In the case when there is an object between the jaws 2 and 3 located symmetrically with respect to the clamping jaws, they begin to compress it, while the force is distributed evenly on both jaws and they securely seize the object being manipulated. From feedback sensor 14, made, for example, by potentiometric, no signal is received to the industrial robot control system.

In the case of inaccurate orientation of the clamping jaws relative to the object being manipulated, one of the jaws, for example clamping jaw 2 (Fig. 1), touches the surface of the item first and stops: As the nopifil w 11 of the pneumatic cylinder 15 is further mixed, the gear wheel 12 starts to run around the stationary shaft 10 of the rail 10 the rod 8, while it acts on the toothed rack 9 of the rod 7, intermediate lever b, the leading link 4, tgu 5 articulating multi-link and clamping sponge 3, moving it with double speed to touch the surface of the manipulated drive Edmeta, after which there is a reliable capture of the subject.

The feedback sensor 14, connected to the gear wheel 12, when compressing a manipulated object asymmetrically positioned relative to the gripping jaws, perceives the difference in relative displacements of the toothed rails 9 and 10 and: provides eccentricity information to the industrial robot control system. The direction of rotation of the feedback sensor 14 determines in which direction the object being manipulated is displaced from the axis of symmetry of the pickup, and the absolute value of the value taken from the feedback sensor in the form of, for example, an analog signal, corresponds to the distance C (Fig. 3), equal to the doubled value of eccentricity S,. At the same time, the value of eccentricity 5 should not exceed half of the size of the clamped object (half of the diameter d), which is usually done for mechanical engineering and machine-tool construction, since for these industries the dimensions of parts moved by industrial robots range from about 3 to 100 mm, and the positioning accuracy of modern industrial robots is no more than + 1.5 mm.

In that case, if the eccentricity of the location of the object being manipulated relative to the axis of symmetry of the grip exceeds half the size of this object (half of the roller diameter), then one of the clamping jaws, for example 3. (Fig. 4), stops touching the manipulated object and the second sponge 2 moves to its limit position. When the limit switch is triggered into the industrial robot control system, a signal is received to stop the process of clamping the manipulated object. From the feedback sensor 14, the control system receives a signal whose value corresponds to a distance l equal to the sum, one of the terms of which is equal to half the diameter of the object being manipulated, and the second to the value of the eccentricity. If the diameter of the object with which the industrial robot handles is known, then the eccentricity is determined by the formula

S ,, i-ds 12,

where -, the eccentricity of the mutual position of the manipulated

subject and capture industrial robot;

difference in relative displacement of the jaws; oL-diameter manipulated

subject.

In the event that the size of the object being manipulated, such as the diameter of the roller, and both clamping jaws do not compress this roller, the control system of the industrial robot by recalculation (according to the signal from the feedback sensor 14 and the corresponding distance z, and the signal from the limit switch that the sponge 2 touches the stop and does not clamp reliably the roller) determines the angle of rotation P of the gripping of the industrial robot in the horizontal plane relative to the center O, equal to

tg f f,

2T

p is the angle of rotation of the grip in the horizontal plane; h — distance from the center of rotation of the arm, work to the midpoint of the clamping jaw area; Pj is the difference in the relative displacement of the jaws. After the jaws have been opened and the gripper has been rotated by an angle f with respect to the center O to position II-II, the clamp is re-clamped. Then, the reverse sensor 14 outputs to the control system a value of 1, equal to twice the eccentricity value of the roller being manipulated with respect to the new II-I position. The eccentricity of the clamping roller relative to the gripping position 1-I is

f Ji- + li

Vo9 about

yr

the distances corresponding to the values taken from the feedback sensor, respectively, at the first and subsequent terminals.

The jaws 2 and 3 are unclamped by means of a return spring 19 after the control system receives a signal to the air distributor, which connects the working cavity of the pneumatic cylinder 15 to the atmosphere. In this case, the spring 19, which rests against the rear flap 17 of the pneumatic cylinder 1) a, moves the piston None of the gear 12 connected to the piston forward. Together with the gear wheel 12, the rails 9 and 10 move with the rods 7 and 8 and together with them the jaws 2 and 3 of the gripper. If the jaws are in a position asymmetrical with respect to the grip axis, then one of the jaws, for example, the jaw 2, is first concerned with

an anvil located on a gripping housing 1 fixed on the front wall of the pneumatic cylinder 16. The movement of the levers 4 and 6, the shaft 8 with the rack 10 stops, and the movement of the rail 9, the shaft 7 and, accordingly, the jaw 3 occurs at double speed to the final position.

When the control system receives signals from two limit switches, the limiting position of the clamping jaws and in the absence of a signal from the feedback sensor 14 (the signal goes through wires 18 passing inside the cylinder cavity and fixed on a special spring coil), it is considered that the gripper is in the original state and ready for further work.

Claims (2)

1. The capture of an industrial robot, comprising a housing, clamping jaws, a drive and a summing mechanism, characterized in that, in order to ensure reliable fixation of objects that are inaccurately oriented relative to the clamping jaws, it is equipped with a feedback sensor, and the summation the mechanism is made in the form of a gear-rack and pinion gear, and the feedback sensor is connected to the gear wheel of this gear. 2. Capture according to claim. 1, characterized in that the drive is made in the form of a pneumatic cylinder one-way action, and a rack-and-pinion gear is located in the pneumatic cylinder body, and the gear wheel of this gear is kinematically connected with the piston of the pneumatic cylinder of the cylinder. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 503714, cl. B 25 J 15/00, 1974. GO 19 P 841962 cpuzj