JPS6134935B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an automatic setup table for automatically setting up a workpiece to be machined with an automatic machine tool.

[Technical background of the invention and its problems]

Recently, FMS (Flexible Manufacturing System) has become popular in many fields. For example, in the machining field, which mainly involves high-mix, medium- to low-volume production,
In FMS, a plurality of automatic machine tools are arranged in a line and an automatic setup device is installed, and these automatic machine tools and automatic setup devices are communicated with each other by transportation means such as an unmanned vehicle or a transportation robot. A method of centrally managing and controlling the automatic setup device and transport means is adopted. In this method, the workpiece is supplied to the conveyance means by holding and fixing the workpiece on a plate that can be attached to the machine tool by the automatic setup device, and the plate on which the workpiece is set is transferred to the conveyance means. This is done by sending the By the way, the automatic setup device is composed of an automatic setup table and a robot installed near the automatic setup table. Then, the various jigs are sequentially stacked on the automatic setup table by the robot according to a predetermined order. Positioning when stacking is performed by fitting a positioning pin into a positioning hole. However, such a fitting operation requires a high degree of positioning accuracy, and it is difficult for general robots that do not have a visual recognition function to perform the above fitting operation quickly and accurately. Moreover, in one set-up operation, it is necessary to perform the fitting operation multiple times, and each time the fitting operation is performed, the positioning error accumulates. For this reason, one way to perform automatic setup work with high reliability is to increase the flexibility of robots by providing them with visual functions, but this is extremely expensive and impractical. Therefore, there has been a need for an automatic setup table that is relatively simple and has the flexibility to perform setup work quickly and accurately.

[Purpose of the invention]

The present invention was made in consideration of the above circumstances, and an object of the present invention is to provide an automatic setup table that is compatible with FMS.

[Summary of the invention]

An index table is installed on the pedestal, and an air curtain forming mechanism is used to support the jig, which is successively weighted and stacked on the index table, so that it can move freely along the top surface of the index table with a small amount of force, and the jig is fitted by a robot. A positioning mechanism is installed to correct positional deviation after alignment.

[Embodiments of the invention]

Hereinafter, the present invention will be described in detail based on embodiments with reference to the drawings.

1 and 2 show a plan view and a front view, respectively, of the automatic setup table of this embodiment. A disk-shaped index table 2 is placed on the top side of the four-legged pedestal 1. This index table 2 is rotated by a required angle by a motor 3 attached to the lower surface of the pedestal 1. A plate-shaped air pallet 4 having a square main surface is placed on the index table 2. A tapered hole 5 is bored in the center of the lower surface of the index table 2 (see FIG. 3). on the other hand,
A positioning pin 6 having a tapered tip formed at the center of the upper surface of the index table 2 and coaxial with the rotating shaft of the motor 3 is installed inside the index table 2 by a movement mechanism using hydraulic pressure or the like. It is planted so that it protrudes from the top surface and can be immersed freely. The positioning pin 6 is then fitted into the tapered hole 5 in a protruding state. Similarly, a positioning pin 6a, which can be freely protruded and retracted by the advance/retreat mechanism, is implanted on the top side of the index table 2 in proximity to the positioning pin 6, and a positioning pin 6a is installed on the bottom side of the air pallet 4. It is provided to fit into the positioning hole. These advancing/retracting mechanisms and positioning pins 6, 6a constitute a first positioning mechanism 6b. Furthermore, air supply holes 4a are bored inside the air pallet 4 to serve as air guide passages. This air supply hole 4a is connected to the air pallet 4.
It is open at multiple locations on the lower surface, and the other end is connected to the compressed air source shown in the figure. These air pallets 4, air supply holes 4a, and compressed air sources constitute an air curtain forming mechanism 7. Also, on the upper surface side of the air pallet 4, there is an NC plate placed on the air pallet 4.
(Numerical Control) An NC with a square main surface, which is a special jig installed in a machine tool.
locating pin 9 for positioning the plate 8;
9 have been planted. On the top surface of the index table 2, there are a plurality of positioning pins 10 for positioning the integrally connected air pallet 4 and NC plate 8 when the positioning pins 6 are recessed. It is planted.
These positioning pins 10 are provided so as to contact two adjacent side surfaces of the NC plate 8 in a positioning state. Furthermore, on the top surface of the index table 2, there are two air
Cylinders 11, 11 are provided. Piston rod 1 of these air cylinders 11, 11
At the tips of 2 and 12, plate-shaped pressing bodies 12a and 12 are provided.
a is attached, and these pressing bodies 12a, 12
a is adapted to press the other side surface of the NC plate 8 that does not come into contact with the positioning pins 10 . These air cylinders 11, 11, piston rods 12, 12, pressing bodies 12a, 12a, and positioning pin 10 constitute a second positioning mechanism 13. Thus, the motor 3, the movement mechanism for the positioning pin 6, the compressed air source that supplies compressed air to the air pallet 4, the air cylinder 11,
11 is connected to an arithmetic control unit (not shown) such as a microcomputer. Although not shown, a jig stand on which various jigs for clamping the workpiece are placed at predetermined positions is installed adjacent to the automatic setup table of this embodiment. In addition, there is also a transport robot (not shown) that transports large jigs such as the NC plate 8, and an assembly robot (not shown) that grasps the clamping jig placed on the jig table and assembles it at a predetermined position. ) are also installed near the automatic setup table of this embodiment, and are operated based on control signals output from the arithmetic control section.

Next, the operation of the automatic setup table having the above configuration will be described.

First, compressed air is blown out from the air supply hole 4a of the air pallet 2, and the index table 2 is
An air curtain of about 20 μm is formed between the index table 2 and the index table 2, and the positioning pins 6, 6a are projected upward from the top surface of the index table 2 by the advance/retreat mechanism provided on the index table 2 to position the air pallet 4. I do. Thus, the positioning pins 6, 6a are recessed below the top surface of the index table 2. Then, the air curtain formed between the air pallet 4 and the index table 2 allows the air pallet 4 to move freely along the horizontal plane, that is, along the upper surface of the index table 2 with a slight force. That is, flexibility is provided during automatic setup. Next, the transfer robot places the NC plate 8 at a predetermined position on the air pallet 4 based on the work program in the arithmetic control section. At this time, even if there is a positioning error such as a slight positional shift or inclination on the transfer robot side, the air pallet 4 side is better than the NC plate 8.
Since the positioning pins 9 of the air pallet 4 can be reliably fitted into the positioning holes of the NC plate 8, the positioning pins 9, 9 of the air pallet 4 can be reliably fitted into the positioning holes of the NC plate 8. Thus, the piston rods 12 of the air cylinders 11, 11 are advanced, and the NC plate 8 is pushed forward by the pressing bodies 12a, 12a.
The sides of the air pallet 4 and the NC plate 8 which are integrally connected by the positioning pins 9, 9 are corrected by pressing the sides thereof against the positioning pins 10. This is done to prevent positioning errors from accumulating in subsequent setups. Next, the jig plate 14 is placed at a predetermined position on the NC plate 8 by the transport robot based on the work program in the arithmetic control section. In this case as well, since the air pallet 4 and the NC plate 8 are integrally movable along the horizontal plane by a small amount, the positioning pin 15 implanted on the upper surface of the NC plate 8...
can be easily and reliably fitted into the positioning hole provided on the lower surface of the jig plate 14 in the same manner as the positioning pins 9, 9. Thus, by driving the air cylinders 11, 11 again, the positions of the air pallet 4, NC plate 8, and jig plate 14, which are integrally connected, can be corrected by pressing the pressing bodies 12a, 12.
a and the positioning pins 10... Then, the assembly robot inserts the cylindrical clamping jig 16 from the jig stand into the fitting hole provided on the upper surface of the jig plate 14. At this time,
Each time each clamp jig 16 is fitted into the corresponding fitting hole, the air cylinders 11, 11 are driven to press the press bodies 12a, 12a and the positioning pin 10.
... carries out the same position correction as described above. Next, the clamp device 17 is taken out from the jig stand by the assembly robot and mounted on the piston portion of the internal cylinder built in the jig plate 14, and then the position is corrected again in the same manner as before. Next, the workpiece 18 is placed on the clamp jig 16 by the transfer robot. Thus, the index table 2
The forward/backward mechanism of the index table 2 is activated to project the positioning pins 6, 6a and stop the air blowout from the air supply hole 4a.
and air pallet 4. Then, an automatic detachable coupler connected to a hydraulic power source (not shown) is attached to the side surface of the jig plate 14, and the jig plate 14
Hydraulic pressure is applied to the internal cylinder through a hydraulic line built into the cylinder. Then, as the piston portion of the internal cylinder descends, the workpiece is clamped and fixed by the clamp device 17. Further, power is supplied to an electromagnetic chuck that is embedded in the NC plate 8 and can be freely magnetized and demagnetized, so that the jig plate 14 is attracted by magnetic force. In this way, the workpiece 18, the jig plate 14, and the NC plate 8, which are integrally connected, can be moved to the workpiece 18 by a transfer robot, an unmanned vehicle, etc.
It is installed at a predetermined seating position of an automatic machine tool, such as a machining center, that processes. On the other hand, after the workpiece 18 has been subjected to the specified processing by the automatic machine tool, the NC plate 8 is again placed on the automatic setup table, and the jig plate 14 is embedded in the NC plate 8 that is sucking the jig plate 14. After demagnetizing the electromagnetic chuck, disassembly work is carried out using a transport robot and an assembly robot. However, in this disassembly work, the positioning pins 6 and 6a are kept protruding from the top surface of the index table 2.
There is no need to form an air curtain between index table 2 and air pallet 4.
In this way, the automatic setup table of this embodiment has the air pallet 4 on the index table 2, which is movable along the top surface of the index table 2, so that various jigs can be fitted one after another. Flexibility in fitting and setting up is increased, and fitting work for setting up can be performed with high accuracy and high efficiency. Therefore, there is no need to provide a particularly sophisticated recognition function such as a visual sensor to the robot that performs the fitting work, and there is an advantage that a relatively inexpensive robot device can be used.

In addition, in the above embodiment, the jig plate 1
Although the number of workpieces placed on jig plate 14 is one, if there are multiple workpieces or if the operating area of the assembly robot does not cover the entire area of jig plate 14, motor 3 should be driven. The index table 2 is rotated by the required angle. However, in this case, the positioning pins 6 and 6a are fitted into the air pallet 4 without forming an air curtain between the index table 2 and the air pallet 4. Close contact. In addition, the air curtain can open the air supply holes 4a on the top surface of the air pallet 4,
and the NC plate 8. Furthermore, the pressing bodies 12a, 12a are
The side surface of the pallet 4 may also be pressed.
Furthermore, if the index function is not required at all for automatic setup work, index table 2
Instead, a conventional fixed table may be used and still be within the scope of the invention.

〔Effect of the invention〕

The automatic setup table of the present invention is provided with an air pallet, giving it flexibility when fitting jigs. Therefore, even if errors such as positional deviation or inclination occur during positioning by the robot, they are absorbed by slight movements in the horizontal direction via the air pallet, allowing setup work to be performed quickly and accurately. Furthermore, since there is no need to use a robot with a visual function for high-precision positioning, it contributes to a reduction in equipment costs.

[Brief explanation of the drawing]

1 and 2 are a plan view and a front view, respectively, of an automatic setup table according to an embodiment of the present invention, and FIG. 3 is an enlarged sectional view showing a main part of an air pallet. 2... Index table (table),
4... Air pallet, 6, 6a... Positioning pin (fitting pin), 6b... First positioning mechanism,
7... Air curtain formation mechanism, 8... NC plate (plate), 10... Positioning pin, 13
...Second positioning mechanism.

Claims (1)

[Claims] 1. A table whose upper surface is formed as a sliding surface, an air pallet that is slidably placed on the sliding surface of this table and has a tapered fitting recess formed in its lower surface, and an air curtain forming mechanism for forming an air curtain between a moving surface and a lower surface of the air pallet to levitate the air pallet; and a tapered fitting pin embedded in the table so as to be protrusive and retractable. a first positioning mechanism for positioning the air pallet by fitting the fitting pin into the fitting recess of the air pallet while the air pallet is floating by the air curtain mechanism; and a plurality of positioning pins erected on the table.
The plate, which is positioned and placed in a removable manner on the pallet and is integrated with the air pallet, is inserted into the plate with the fitting pin recessed into the table and the air pallet floating by the air curtain forming mechanism. An automatic setup table comprising: a second positioning mechanism that positions the plate by pressing the plate so as to bring it into contact with the positioning pin.