JP2007185746A - Part gripping mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a part gripping mechanism, using a multi-axis robot freely coping with various alterations in a part to be machined. <P>SOLUTION: This part gripping mechanism includes: a parallel hand 4 mounted on the multi-axis robot and having a pair of claws 11; and a part carrying tool 5 for carrying a part gripped by the paired claws 11 of the parallel hand 4. The claws 11 have pins 10 on the opposite surfaces, and the corner parts of the opposite surfaces are chamfered or machined to a curved surface. The part carrying tool 5 includes: a body part 5d gripped by the paired claws 11 of the parallel hand 4; and a holding part 5e holding a part. The side surface of the body part 5d is provided with a pair of gripping grooves 5a where the claws 11 are fitted, and holes 5c to which the pins 10 of the claws 11 are fitted are formed in the gripping grooves 5a. The holding part 5e is provided on the end face outside of the side surface of the body part 5d and has a magnet 5f for attracting the part. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a component gripping mechanism using a multi-axis robot.

  When mass-producing low-priced, high-quality industrial parts, it is common to use unmanned and automated integrated processing lines with processing machines dedicated to individual parts in accordance with the number of production varieties. When processing different varieties in an integrated processing line, many lines stop all equipment and perform product change setup. In addition, the above-mentioned dedicated processing machine, such as component gripping, positioning, and component processing, is mainly realized by a component transport apparatus using an orthogonal coordinate system auto hand.

  On the other hand, in the manned assembly work site, instead of the conventional consistent belt conveyor production method, a distributed cell production method has been introduced, and steady results have been achieved.

Patent Document 1 discloses a robot apparatus that can be used at these production sites and that can efficiently use a work space.
Japanese Patent Publication No. 7-73781

  There is also a multi-product production system that has multiple unattended and automated integrated processing lines in a Cartesian coordinate system, but the equipment operation rate is low when production fluctuations occur, and the power consumption of the air conditioning equipment increases due to an increase in the space occupied by the line In this case, there are many things that need to be improved. In addition, the unattended and automatic integrated machining line of this Cartesian coordinate system is a dedicated integrated line, so it is necessary to make a large-scale product change setup with all lines stopped, and a great deal of time and labor is required. To spend. The main reason is that the auto coordinate system hand is a major device element. In order to deal with equipment changes in parts shape and machining elements that are essential for product type change setup, jigs and auto-hands must be replaced, and many sensors must be adjusted accordingly. This is because it is necessary to occur.

  In the cell production system, it is difficult to secure skilled workers in the future, such as the declining birthrate and aging population and the separation of young people from science and engineering. For this reason, unmanned and automatic multi-product processing that combines the flexibility of manual processing and the high efficiency of unmanned dedicated processing machines to achieve both high-mix mass production and low-cost and efficient production in the parts processing field. There is a need to design the machine.

  Therefore, an object of the present invention is to provide a component gripping mechanism using a multi-axis robot that can freely cope with various changes of a workpiece.

  In order to achieve the above object, the component gripping mechanism of the present invention is a parallel hand equipped with a pair of claws, which is mounted on a multi-axis robot, and a component gripped by a pair of claws of a parallel hand. In a component gripping mechanism having a jig, the claw has pins on opposing surfaces facing each other, the corners of the opposing surface are chamfered or curved, and the jig is gripped by a pair of claws of a parallel hand. A main body part and a holding part for holding a part are formed, and a pair of gripping grooves for fitting the claws are formed on the side surface of the main body part, and holes for fitting the claws pins are fitted in the gripping grooves. The holding portion is provided on an end surface other than the side surface of the main body portion, and has a magnet that attracts components.

  ADVANTAGE OF THE INVENTION According to this invention, it can respond to the various change of a to-be-processed part freely by simple operations, such as changing the jig for conveyance according to conveyance of components. Further, by applying the present invention to a machine cell production method, it becomes possible to immediately cope with production fluctuations.

  Hereinafter, description will be given using an example in which a rod-shaped roller is a workpiece.

  FIG. 1 shows an external perspective view of an example of a multi-axis robot applicable to the present invention. FIG. 2 shows a perspective view of the parallel hand. 3 and 4 show a state in which the component conveying jig is held by the parallel hand. 5 to 8 show a side view, a plan view, and a perspective view of the component conveying jig. 9 and 10 are cross-sectional views showing a state in which the pins of the parallel hand are inserted into the holes of the holding grooves of the component conveying jig. FIG. 11 is a three-sided view of the parallel hand, and Table 1 is a dimension table showing dimensions of each part of the parallel hand shown in FIG. FIG. 12 is a plan view of the parallel hand, and FIG. 13 is a perspective plan view showing a state in which the parallel hand grips the component conveying jig.

  The parallel hand 4 is attached to the flange 1 a of the 6-axis multi-axis robot 1. By attaching the parallel hand 4 to the multi-axis robot 1, the parallel hand 4 can rotate around the axis O as well as the X, Y, and Z directions shown in FIG. 3. The parallel hand 4 has two claws 11 provided with pins 10. The nail | claw 11 is arrange | positioned so that the pin 10 may oppose. These two claws 11 move close to each other in the closing direction when gripping the component conveying jig 5. Further, when releasing the gripping of the component conveying jig 5, the parts are moved away from each other, that is, in the opening direction. The pin 10 is inserted into a hole 11 a formed in the claw 11. The claw 11 is chamfered so that the side where the pin 10 protrudes, that is, the side where the left and right claws 11 face each other can be easily inserted into the gripping groove 5 a of the component conveying jig 5.

  The component conveying jig 5 has a main body part 5d and a holding part 5e. Two gripping grooves 5a and two second grooves 5b are formed on the side surface of the main body 5d. The holding grooves 5a are grooves into which the claws 11 of the parallel hand 4 are fitted, and two grooves are formed on each side of the main body 5d. A hole 5c into which the pin 10 of the claw 11 is fitted is formed in the gripping groove 5a. The second groove 5b is formed in parallel with the gripping groove 5a. The second groove 5b has a notch 9 (see FIG. 25) formed in the table 3 for the component conveying jig 5 gripped by inserting the two claws 11 of the parallel hand 4 into the gripping groove 5a. ) To be inserted in Two positioning holes 5h into which positioning pins 7 formed on the base 8 are fitted are formed on the upper surface of the main body 5d. The holding portion 5e has holes 5g formed at four corners thereof, and a magnet 5f provided at the bottom thereof. The four magnets 5f are for attracting and transporting the roller 6 which is a workpiece.

  FIG. 14 shows the component conveying jig 5 in a state where a roller 6 as a workpiece is held. As described above, since the magnet 5f is provided at the bottom of the hole 5g, the roller 6 is held in a suspended state by the holding portion 5e without dropping.

  FIG. 15 is a diagram illustrating a state where the combination of the workpiece 6 and the component conveying jig 5 is inverted and palletized on the table 8 on which the component conveying jigs 5 are arranged.

  Positioning pins 7 are formed on the base 8 in accordance with the positioning holes 5 h of the component conveying jig 5. The positioning pins 7 of the table 8 can be easily inserted into the positioning holes 5h of the component conveying jig 5 with fingers or a robot hand. However, if the multi-axis robot 1 is equipped with an image recognition device, positioning on the platform 8 can be performed roughly, and in that case, the positioning pins 7 and the like are not essential.

The palletizing to the state shown in FIG. 15 may be performed manually or by a robot. That is, if a vertical placement and depalletizing robot and a robot optional visual device are added to the experimental machine cell, it can be easily and automatically palletized and depalletized. The method is described in detail in the instruction manual of the robot (December 1996, published by Denso FA Division, small vertical articulated DENSO robot MODEL VS-C SERIES, instruction manual B (programming) page 8- 309 and later and pages 9-1 and later).
(Example)
An embodiment of the present invention will be described by taking as an example the step of dip-coating the surface layer coating material on a charging roller which is one of functional parts for electrophotography. In addition, a present Example does not limit the workpiece etc. which are the object of invention.

  As for the material of the component conveying jig 5, the main body 5d is a POM material, and the holding part 5e is mainly aluminum. Two positioning holes 5h in the table 8 on which the component conveying jigs 5 are arranged are formed on the upper surface of the component conveying jig 5.

  The chamfer 11 was chamfered 2 mm on the inner surface of the claw 11, and the corner of the groove of the component conveying jig 5 was chamfered. The reason why the chamfering process of the claw 11 is increased is to reduce the machining cost because the number of manufactured claw is only one pair, but dozens of jigs are required. By providing 2 mm chamfering on the inside of the claw 11, the vertical positioning accuracy of the robot teaching can be roughly reduced to about ± 1 mm, and the teaching work load can be drastically reduced.

  Next, a part creation procedure for a coating machine cell experiment will be described.

  SUM material rod with outer diameter φ6mm length 252mm for paper size A4 charging roller and SUM material rod with outer diameter φ6mm length 355mm for paper size A3 charging roller A cored bar was used. Next, an appropriate amount of a raw rubber material mainly composed of epichlorohydrin rubber, light calcium carbonate, plasticizer, and the like was blended, and then kneaded for 10 minutes in a closed mixer adjusted to 45 ° C. to prepare a raw material compound. To this compound, sulfur as a vulcanizing agent, DM and TS as a vulcanization accelerator were added, and kneaded for 10 minutes in a two-roll machine cooled to 20 ° C. The obtained compound is produced by an extrusion molding machine so as to form a roller with an outer diameter of Φ15 around the above two types of metal cores, heated and steam vulcanized, and then polished so that the outer diameter becomes φ12. The elastic roller was obtained. The core bar was cut off so that the left and right sides of the roller were exposed 10 mm.

  A hole 5g that is 0.1 mm larger in diameter than the core metal is formed in the 70 mm square surface of the component conveying jig 5, and a magnet 5f is embedded in the bottom of the hole 5g. Four rollers 6 were inserted into the holes 5g for each of the A3 and A4 paper sizes, and the workpiece and the component conveying jig 5 were combined. Since the SUM steel material of the core metal is fixed by the action of the magnet 5f embedded in the bottom of the hole 5g of the component conveying jig 5, the roller 6 does not fall from the component conveying jig 5 even when the roller 6 is suspended. Further, since the hole 5g is 0.1 mm larger in diameter than the core metal of the roller 6, it can be easily detached. FIG. 14 shows a state in which a masking cap 30 for dip coating is attached to the tip of the roller 6. According to the above procedure, two sets of charging rollers and jigs for dip coating using an experimental machine cell were prepared, each having 8 sets.

  Next, a conceptual diagram of the coating machine cell is shown in FIG. This cell is mainly composed of a single-axis slider 2, a three-way chuck 22, a three-way chuck claw 23, and a coating pot 31 (see the figure). As shown in FIG. 17, the three-way chuck 22 mounted on the single-axis slider 2 grips the main body 5 d of the component conveying jig 5 by the three-way chuck claw 23. FIG. 18 is a perspective view showing a state in which the component conveying jig 5 holding the roller 6 is held by the three-way chuck 22. Although not shown, this coating machine cell is additionally provided with a coating chamber cover, a HEPA filter, a solvent ventilator, an automatic door, etc. as ancillary equipment. The application pot 31 is built with the minimum necessary tools for this experiment, and when used in a production apparatus, a circulation system such as a paint circulation pump, an overflow liquid receiving tank, and a foreign matter removal filter is prepared.

  The surface layer coating material used for dip coating was prepared by the following method. After a mixed liquid containing lactone-modified acrylic polyol, conductive tin oxide, and methyl isobutyl ketone was dispersed with a sand mill, a butanone oxime block of hexamethylene diisocyanate was added and dissolved to prepare a coating for the surface layer.

  First, the A4 paper size charging roller was dip-coated using the obtained paint, and then the A3 paper size charging roller was dip-coated after the setup change operation. Hereinafter, the state of the application work by the experimental machine cell will be described with reference to FIG.

  The multi-axis robot 1 is taught in advance for necessary operations, and can be operated unattended. The robot 1 first clamps the component conveying jig 5 to which the roller 6 is attached with the parallel hand 4 and the left and right claws, and picks up the workpiece 6 from the holding table 8 (FIG. 19A).

  Thereafter, the workpiece 6 is moved to the uniaxial slider 2 of the coating machine cell (FIG. 19B). During the movement, the respective axes are driven simultaneously, and the roller 6 as the workpiece is turned upside down, and then delivered together with the component conveying jig 5 to the coating machine cell. That is, as shown in FIG. 20, the component conveying jigs 5 arranged on the table 8 are grasped by the parallel hand 4 of the multi-axis robot 1 (FIG. 21). Next, during the movement from the table 8 to the uniaxial slider 2 of the coating machine cell, the parallel hand 4 is rotated around the axis O (FIG. 22), and the roller 6 that has been directed vertically upward is reversed upside down. Turn downward (FIG. 23).

  Next, the component conveying jig 5 with the roller 6 suspended is delivered to the three-way chuck 22 of the single-axis slider 2. The single-axis slider 2 that has received the component conveying jig 5 descends the three-way chuck 22 to lower the roller 6 into the coating pot 31 at a predetermined speed, and dip-coating the surface layer paint (FIG. 24). ).

  When the dip coating of the surface layer coating is completed, the multi-axis robot 1 again takes the coated roller 6 together with the component conveying jig 5 from the coating machine cell. After the take-up, the multi-axis robot 1 fits the component conveying jig 5 into the notch 9 of the table 3 and dries the roller 6 (FIGS. 19C and 25). The component conveying jig 5 is held by the table 3 by inserting the second groove 5 b into the notch 9. The cradle 3 is a so-called finger-drying cradle that gives a part with a drying time until the coating surface is stabilized to the extent that the coated surface after application is dry. The table 3 is a curved surface of an aluminum plate along the movement trajectory of the six-axis robot arm. Although not shown, the notch 9 is provided with a proximity sensor that detects insertion of a jig. The placing table 3 can also be used as a place for placing parts to the robot cell adjacent to the machine cell. In that case, the notch 9 is preferably a parallel rail shape rather than an enclosed shape.

  Next, it waits for passage of finger touch drying time until the coating film after application | coating is stabilized in the stand 3 for drying. While waiting for the drying time, the multi-axis robot 1 repeated the above-described coating operation using a plurality of cutouts 9. After the touch drying is completed, the multi-axis robot 1 takes the roller 6 together with the component conveying jig 5 from the placing table 3, reverses the workpiece 6 upside down, and then conveys the workpiece 6 to the coated product placing place and leaves it to stand. A series of operations was completed.

  In addition, for a series of operations of the machine cell used in this example, robot controller RC3 (manufactured by Denso Corporation), PLC (manufactured by Mitsubishi Electric Corporation), controller EZMC36 (manufactured by Oriental Motor Co., Ltd.), and proximity sensor are used. Using. The robot program and sequence ladder program to control these were fully automatic. The specifications of each component used in this example are summarized in Table 2.

  In this embodiment, eight sets of A4 paper size and A3 paper size charging rollers and parts conveying jigs are set to be continuously operated by the multi-axis robot under the condition of a coating tact time of 60 seconds. 9 was used in three places.

  The operation during coating was carried out smoothly and unattended. In addition, the part changeover work has the same outer diameter of the core bar, so the part conveyance jig can be used in common. As a result, the setup to accommodate different lengths is a program for multi-axis robots and single-axis sliders. It was very easy with only changes. The program was changed by replacing the program corresponding to each part prepared in advance, and the required time was about 30 minutes including the preparation of the PCL program operation personal computer. In addition, the number of setup change personnel was one.

  As mentioned above, although the example of unmanned automatic component processing was demonstrated about the roller immersion coating process, you may replace the coating machine cell 2 in a figure with another processing machine cell, for example, a grinding machine cell, and the workpiece 6 is replaced with other components. It is possible to carry out different types of processing.

What should be noted in the example of the coating process is as follows. In other words, even when the length, diameter, and type of paint to be applied are changed to other types, it is possible to immediately handle various types by replacing the jig. In addition, it is possible to respond to various types of products immediately by switching the operation teaching program of the multi-axis robot 1, preparing different types of coating machine cells, and preparing a necessary number of places for placing workpieces. Further, even when different types of workpieces are mixed, if a part recognition method such as an IC tag and a teaching program are used in combination, the workpiece can be automatically transferred to a required machining machine cell without an unmanned operation. This indicates that the machine / robot cell can function as well as the manned cell by the skilled worker.
(Comparative example)
FIG. 26 shows an example of an electrophotographic charging roller surface coating pilot plant using a conventional orthogonal coordinate system auto hand.

  The roller as the part to be coated is prepared in the same manner as in the example. However, the component conveying jig is not used in this comparative example, and the A4 paper size component and the A3 paper size component are each conveyed by a finger having a special length.

  Hereinafter, the component processing application procedure and the setup change procedure will be described with reference to FIGS. 26 and 27. FIG. An example of an electrophotographic charging roller surface coating pilot plant to which the present invention is applied is shown in FIG.

  Since the conveyance of the Cartesian coordinate system is performed by laying a roller part (hereinafter referred to as a part 99) of an object to be coated in the Y-axis direction, the part 99 is automatically depalletized in the Z-axis direction from the horizontally placed box 101. The finger 102 of the comparative example needs to be replaced depending on the length of the component 99, and in that case, the reserve position confirmation sensor 105 needs to be adjusted.

  Thereafter, the component 99 is conveyed in the X-axis direction by the automatic hand 100, and is lowered and placed in the Z-axis direction at a predetermined location on the loading stocker 104 (reservation table). The input stocker 104 also needs to adjust the width of the double-sided chuck and the position of the sensor 103 depending on the length of the component 99.

  When the component 99 is put into the coating machine 110, the finger 102 is inverted 90 degrees from the X-axis direction to the Z-axis direction. Here, it is necessary to adjust the setup to cope with the difference in length of the component 99. After the coating operation is completed, the coated parts are moved in the X-axis direction (in the drawing, the Y-axis direction for convenience of paper) until the drying stocker. Next, the parts are placed in a drying stocker 200 as shown in FIG. 26 by a reversing machine, and finally automatically palletized. The setup adjustment for different parts length is performed in the same way as in the case of the input stocker. In FIG. 26, the direction of 180 ° from the coating pot portion is changed for convenience of explanation, but the actual plants are laid out in a line.

  In the case of a dedicated plant using a normal Cartesian coordinate system auto hand, the time spent for the setup change work for different parts lengths is performed using one work shift, and it takes about 8 hours. The number of setup changers, such as finger replacement and sensor adjustment, is physically unreasonable and requires at least two people.

  Table 3 shows a comparison table showing the difference between the example and the comparative example when the roller length is changed from the A4 paper size electrophotographic part to the A3 part.

(Production line comparison)
FIG. 29 is a conceptual diagram of an integrated production line of the prior art, and FIG. 30 is a conceptual diagram of a new machine cell production line that is made possible by applying the present invention.

  As can be seen in the figure, the integrated production line is directly connected to each process, which is advantageous for minimum cost production. However, time and cost are required to set up equipment that can handle production fluctuations, such as changing the machining method and workpiece. It is disadvantageous. In addition, when each process fails and a line stop occurs, all the lines stop operating because they are directly connected.

  On the other hand, although the machine cell line is difficult to save space, since the processing cells and the like can be freely combined and infinitely combined, it is possible to immediately respond to production fluctuations such as changes in processing methods and workpieces. FIG. 30 shows an example in which the “processing 3” and “flanged 2” processes are expanded as compared with FIG. When machine cell lines are developed and proliferated in this way, production lines can not be stopped theoretically because other cells can complement each other when individual cells fail. Furthermore, the concept of an integrated production line disappears at the time when machine cells are highly developed, and the production line evolves into a single complex production plant. In this futuristic factory, it is not necessary to prepare as many integrated production lines as the number of varieties, and the ultimate production factory that can cope with production fluctuations can be realized. Compared to the conventional multi-variety production method in which multiple dedicated automatic machines are lined up in parallel, energy savings will be achieved by improving the operating rate of the equipment, and CO2 emissions will be reduced by reducing energy consumption of the air conditioning equipment by reducing the line occupation space. Can do.

1 is an external perspective view of an example of a multi-axis robot applicable to the present invention. It is a perspective view of an example of the parallel hand of the present invention. It is a figure for demonstrating holding | grip of the components conveyance jig by a parallel hand. It is a figure explaining the state which hold | gripped the component conveyance jig with the parallel hand. It is a side view of a component conveyance jig. It is a side view of a component conveyance jig. It is a top view of a component conveyance jig. It is a perspective view of a component conveyance jig. It is sectional drawing which shows the condition where the pin of a parallel hand is inserted in the hole of the holding groove | channel of a component conveyance jig. It is sectional drawing which shows the condition where the pin of a parallel hand is inserted in the hole of the holding groove | channel of a component conveyance jig. It is a three-sided view of a parallel hand. It is a top view of a parallel hand. It is a perspective top view which shows the state which the parallel hand hold | gripped the component conveyance jig. It is a perspective view of the component conveyance jig holding the workpiece. It is a figure which shows the state by which the component conveyance jig holding the workpiece was palletized. It is a conceptual diagram of a coating machine cell. It is a perspective view of a claw for a three-way chuck for gripping a component conveying jig. It is a perspective view which shows the state by which the components conveyance jig | tool holding the to-be-processed object was hold | gripped by the three-way chuck. It is a figure which shows the mode of the application | coating operation | work by the experimental machine cell. It is a figure which shows the component conveyance jig holding the workpiece arranged on the stand, and the multi-axis robot equipped with the parallel hand. It is a figure which shows the multi-axis robot which grabbed the component conveyance jig holding the workpiece arranged on the stand with a parallel hand. It is a figure which shows the state in which the multi-axis robot is rotating the parallel hand so that a component conveyance jig may be reversed upside down during a movement. It is a figure which shows the state which turned the workpiece which faced the vertical upper direction upside down, and turned to the vertical downward direction. It is a figure which shows the dip coating process of the coating material for surface layers of a to-be-processed object. It is a figure which shows the condition which mounts the component conveyance jig holding the to-be-processed object in the notch of a stand, or takes out from a notch. It is an example of the charging roller surface layer coating plant for electrophotography using the conventional orthogonal coordinate system auto hand. It is a figure explaining a component process application | coating procedure and a setup change procedure. It is an example of the charging roller surface layer coating plant for electrophotography to which the present invention is applied. It is a conceptual diagram of the integrated production line of a prior art. It is a conceptual diagram of a new machine cell production line made possible by applying the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Multi-axis robot 4 Parallel hand 5 Parts conveyance jig 5a Gripping groove 5c Hole 5d Body part 5e Holding part 5f Magnet 10 Pin 11 Claw

Claims (3)

In a component gripping mechanism having a parallel hand with a pair of claws attached to a multi-axis robot, and a jig for transporting a component gripped by the pair of claws of the parallel hand,
The claw has pins on opposing surfaces facing each other, and a corner portion of the opposing surface is chamfered or curved.
The jig has a main body portion held by the pair of claws of the parallel hand, and a holding portion for holding a component,
A pair of gripping grooves into which the claws are fitted are formed on the side surface of the main body portion, and holes into which the pins of the claws are fitted are formed in the gripping grooves,
The holding part is provided on an end face other than the side face of the main body part, and has a magnet that attracts the part.   The component gripping mechanism according to claim 1, wherein a pair of second grooves are formed on the side surface of the main body portion in parallel with the gripping grooves. The component gripping mechanism according to claim 2, further comprising a pedestal formed with a notch on which the jig is placed by inserting the pair of second grooves of the jig.

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