DD287902A5 - WORKPIECE CHANGER WITH ANDRUECE DEVICES - Google Patents

Abstract

The invention relates to a workpiece change gripper with pressing devices for handling workpieces, tools and clamping devices in self-restraining manufacturing cells, in particular in flexible manufacturing systems. The invention aims to avoid an electrical interface when Gripper finger change, also Schraegstellungen of workpieces should be recognized and the workpieces are used plan in the feed. This is achieved according to the invention by a pressure jaw being slidably mounted on each gripper finger against the action of a compression spring and the pressure spring is supported against an adjustable ring on the gripper finger, in which a jig connected with the pressure jaw is guided extended to the base jaws and there is provided with a Wirkflaeche which operates a fixed to the base jaw contactless switch. Fig. 1 {workpiece change gripper; Gripping fingers; Andrueckbacke; Compression spring; adjustment; Stoeszel; Counter; rolling element; Linear ball bearings; Huelse}

Description

For this 3 pages drawings

Field of application of the invention

The invention relates to a workpiece changing gripper with pressing devices for handling workpieces, tools and clamping devices in selbstüstüstenden manufacturing cells, especially in flexible manufacturing systems.

Characteristic of the known state of the art

It is a gripping tool for a mounting robot known, the gripper jaws are movably mounted in the gripper finger against the action of a spring in the axial direction of the Greiferfingeis. The plunger of a signal generator is located on the gripper jaws. His signals indicate too high joining forces and influence the workflow via the control of the assembly robot. A transferred application of this solution to a workpiece change gripper would considerably restrict the area of use due to the necessary use of gripper jaws with a step. When gripper finger change the electrical interface for the signal generator must be operated. This solution is costly, cumbersome in the automatic gripper finger change and not universally applicable. (DD 235219- B 25J 19/00) Bai another gripping tool is mounted on each gripper jaw a displaceable against the action of a spring or pivotable pressure lever. The arrangement of the gripper jaw brings with it that with each change of the gripper jaw and also with each change of the gripper finger of the pressure lever is changed with. As a result, a pressure lever with bearing and spring must be provided for each gripper jaw. Signalers can hardly be arranged at this point, as it does not allow the space. Furthermore, there arranged signalers would be exposed to heavy pollution and a Bechchigungsgesfahr. Also, such an arrangement would require an electrical interface in the gripper finger change with the disadvantages already described. (DE 2930006 - B 23 Q 7/04)

Object of the invention

The invention provides a workpiece change gripper to be created with arranged on the gripper fingers Andrückeinrichtungen, which can be adjusted while maintaining the Andrückfunktion automatically different workpieces, with an electrical interface should be avoided. The gripper should use simple, low-cost gripper bag and be provided with reusable pressing jaws.

Explanation of the essence of the invention

The invention has the object of providing a workpiece changing gripper with pressing function for handling workpieces, tools and clamping devices, which permits a gripper finger change, has no electrical interface and ensures a secure three-point system of We: kstücke in the chuck of the machine. Furthermore, the task is posed to determine Schrägstellongen of workpieces on the transport pallet by means of a probing and properly stored workpieces with a constant Abgriffmaß. This object is achieved in that on each gripping finger a pressure jaws against the action of a compression spring slidably mounted against rotation and that the compression spring is supported against an adjustable ring on the gripper ring, in which a connected to the Andrückbacken ram is guided, the free end extends to the base jaws and there is provided with an effective surface which actuates a contactless switch mounted on the base jaws.

In an embodiment of the invention, the pressure jaws for improving the friction conditions to the handling object

the pressing surface provided with rolling elements.

To carry out detection routines are connected to as many as possible via guides with the gripper body Gripper base jaws by means of clamps Initiators parallel to the direction of movement of the gripper fingers and perpendicular to the Movement direction of the Andrückbackens arranged and linked control technology with the robot controller. At each Andrückbacken a plunger is mounted so that its direction perpendicular to the base jaws and

runs parallel to the gripping finger, with the effective surface of the im turned against the gripping ring arranged ring out

Tappet is always parallel to the button of the switch. The ring carries a sleeve surrounding the compression spring. Ausführungsbelsplel The invention will be explained in more detail in a preferred embodiment. In the accompanying diagrams show Fig. 1: a gripping finger with pressure device Fig. 2: a workpiece change gripper, equipped with two gripper fingers including gripper finger integrated

Pressing devices, when probing a skewed workpiece Fig. 3: e'nen workpiece change gripper with workpiece in the view from below Fig.4: provided with rolling elements Andrückelement

The workpiece change gripper 1 consists of a gripper body 2 with two or more longitudinally displaceable and

driven fixed base jaws 3, which are connected via a mechanical interface 5, each with a gripping finger 4, wherein this, provided with a longitudinal guide 6, which serves to prevent rotation of the movably mounted on the gripping finger 4 Andrückbackens 7, equipped with a sliding adjustment ring 8 is, against which a compression spring 9 is supported, biased with its other side, abuts the Andrückbacken 7.

The gripping fingers 4 are cylindrical. At its lower, the handling object end facing are changeable Gripping jaws 10 attached by means of fastening elements 11, against which in its initial position of the prestressed Andrückbacken 7 is supported. To improve the friction conditions between the Andrückbacken 7 and the workpiece 12th

during the gripper closing 7 rolling elements 13 are integrated in Andrückbacken.

The pressure jaws 7 opposite adjusting ring 8 carries a sleeve 14, the pressure spring 9 from contamination

protects.

In Andrückbacken 7, a plunger 15 is adjustably mounted, which is parallel to the gripping finger 4, in a bore 16 of the Adjusting ring 8 is guided and has an active surface 17 which extends parallel to the button 18 of the switch 19. The workpiece changing gripper 1 is connected to the base jaws 3 in corresponding clamps 20 with switches 19 or others

equipped switching or measuring in particular non-contact transducer. This ensures that the relative movement between the plunger 15 and the switch 19 is equal to zero in an actuation of the Greiforgano in the direction of the gripper finger movement.

The transverse guide 21 serves to receive the gripping fingers 4 in a gripper finger magazine, not shown. Thus, the described arrangement allows a gripper finger change on a sensor-mounted gripper bypassing a

electrical interface.

The equipping each gripper finger 4 with a separate Andrückbacken 7 causes moreover as a result of the mechanical Decoupling the Andrückbacken 7 compared to a conventional Andrückbrücke a relatively stable three-point system surface Workpieces 12 on the Andrückbacken 7 in the gripper 1, represented by the contact points 22nd The sequence of movements until the gripping of a workpiece 12 is as follows: The workpiece change gripper 1 is positioned over the workpiece 12 to be handled. He is in rapid until the Expected range introduced, at the limit is switched to creep speed. The gripper fingers4 are corresponding

opened the workpiece diameter. The bumps! 15 is preset in accordance with a to be realized Abgriffsmaß in Andrückbacken 7. When lowering, for example, first touches the left Andrückbacken 7 in the probing point 23, the workpiece 12, whereupon after passing through a constant (set) path of the left switch 19 triggers a switching signal. The same

Process takes place on the right Andrückbacken, contacted in the probing points 24. The time difference between the two switch signals corresponds to the lowering speed of a path difference X, which in turn embodies the measure of workpiece tilt in a coordinate. If the amount X is in the allowable range, the gripping operation is continued, the amount X exceeds the maximum allowable Operator call triggered. A caused by a deformed transport pallet or by foreign body workpiece skew causes the Gripper symmetry axis 25 and the workpiece axis of symmetry 26, in particular in rotationally symmetrical workpieces, itself

cross. The larger the angle between the two axes of symmetry 25 and 26, the less accurate the amount X reproduces the actual skew, since the first-fitting Andrückbacken 7 (right) contacted on its surface, the second

Place contacting Andrückbacken 7 (left) contrast, the workpiece 12 touched with its tip. The actual clamping operation of the workpiece 12 in the gripper is the following:

- the workpiece 1? touches the right Andrückbacken 7, which is guided straight by means of the rotation 27 along the gripping finger 4,

- The compression spring 9, already biased, is stretched until the end of the lowering of the gripper,

- It moves in the Andrückbacken 7 preset fixed plunger 15 which is guided in the guide 16, upwards, wherein in a defined relative position of the active surface 17 of the plunger 1 b to the button 18 of the switch 20 in this a switching signal is triggered,

the switching signal causes a stop of the gripper lowering movement or a further lowering by a programmed amount and subsequently stopping,

- Is this operation on all Andrückbacken 7, and X is within the allowable range, the clamping movement of the gripping fingers 4 takes place in the direction of the gripper axis of symmetry 2C,

- While rolling the rolling elements 13 of the Andrückbackens 7 on the surface of the workpiece 12 from. Thus, the workpiece 12 is securely clamped in the gripper 1.

Thereafter, the gripper 1 is moved by an industrial robot to the chuck of the machine tool. There, the workpiece 12 is inserted in a known manner plan into the chuck.

Claims (5)

1. workpiece change gripper with arranged on gripper fingers Andrückeinrichtungen, wherein the gripper fingers mounted on a base jaws and movable gripper jaws are attached to the free end of the gripper fingers, characterized in that on each gripping fingers (4) a pressure jaws (7) against the action of a compression spring (9 ) is supported displaceably mounted against rotation and that the compression spring (9) against a on the gripper finger (4) adjustable ring (8) is supported, in which a with the Andrückbacken (7) connected plunger (15) is guided, whose free end until Base jaws (3) extended and there with an active surface (17) is provided which actuates a fixed to the base jaw (3) non-contact switch (19). 2. workpiece change gripper according to claim 1, characterized in that the pressure jaws (7) is supported in its lowermost position against the gripping jaws (10). 3. workpiece change gripper according to claim 1 and 2, characterized in that the bearing of the pressure jaw (7) on the gripping finger (4) is a linear ball bearing. 4. workpiece change gripper according to claims 1 to 3, characterized in that the workpiece (12) contacting surface of the Andrückbackens (7) with rolling element (13) is provided. 5. workpiece change gripper according to claims 1 to 4, characterized in that the on the gripper fingers (4) adjustable ring (8) carries a compression spring (9) einhausende sleeve (14).