JPH09248733A - Tool transfer device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a platen and a moving piece from being damaged by providing means of stopping the piece when the value of pressure in an air flow passage is at a predetermined level or below. SOLUTION: When compression air is not supplied to a moving element 2 from a compressor 22, the value of pressure in the compression air detected by a pressure switch 16 becomes a predetermined value or below so that a tool mounted on the movable member 2 is stopped by a controller 17 and the compression air stored in an accumulator 13 flows toward the movable member 2 by means of a check valve 14. Namely, even if the supply of compression air from the compressor 22 is stopped, compression air is supplied from the accumulator 13 to the movable member 2 since compression air is preliminarily accumulated in the accumulator 13. Accordingly, the member 2 and a platen 6 are not brought into contact with each other until the member 2 stops, thereby preventing generation of mutual damage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool transfer device capable of transferring a tool provided on a mover of a linear motor to a desired position.

[0002]

2. Description of the Related Art Conventionally, in a planar linear motor, which is a type of linear motor, a mover moves on a platen as a stator, which is an orbit, by utilizing the attractive force of an electromagnet. There has been an electronic component mounting device as a tool transfer device using this planar linear motor. In this electronic component mounting apparatus, the platen is disposed above a table on which a substrate or the like is mounted, and the mover is disposed so as to face the substrate mounted on the table. Further, the mover is provided with a nozzle as a tool for sucking an electronic component.

In this plane linear motor, since the mover moves smoothly on the platen, compressed air is jetted from the bottom surface of the mover, and the pressure of the jetted air and the attraction force by the electromagnet are balanced. A small gap (10 to 20 μm) was kept between the mover and the platen. The compressed air is generated by a compressor, passes through a tube having one end connected to the compressor, and reaches a mover through a filter and a regulator having the other end of the tube connected by a connector.

[0004]

However, in the conventional tool transfer device using the linear motor, since the compressed air generated by the compressor is guided to the filter through the tube, the tube breaks or bends in the middle, Alternatively, if the compressed air does not reach the mover because the tube comes out of the filter connector, the gap between the mover and the platen cannot be maintained, and the mover comes into contact with the platen. .

In particular, when contact occurs during movement of the mover,
The bottom surface of the mover and the surface of the platen were sometimes scratched. This scratch is 10 to 20 μm, which is the size of the gap.
If the protrusion exceeds the size, there is a problem that the mover rides on the scratch while moving on the platen and cannot move smoothly.

The present invention has been made to solve the above-mentioned problems, and even if the supply of compressed air from the compressed air generating means to the mover is stopped while the mover of the linear motor is moving, An object of the present invention is to provide a tool transfer device that does not damage the platen and the mover.

[0007]

In order to achieve this object, a tool transfer device according to claim 1 comprises a work table,
A linear motor that supplies the compressed air generated by the compressed air generating means to the mover via an air flow path to levitate the mover with respect to the stator, and runs the mover in a levitated state; A tool provided on the mover, which is intended for moving the tool to a desired position by the linear motor, and in particular, a pressure detection means arranged in the air flow passage for detecting the pressure of the compressed air, And a mover stopping means for stopping the mover when the pressure value detected by the pressure detecting means becomes equal to or less than a predetermined value. Therefore, when the compressed air is no longer supplied from the compressed air generating means to the mover, the pressure value of the compressed air detected by the pressure detecting means becomes equal to or less than a predetermined value, and the mover stopping means moves the movable air. Stop the tool provided on the child.

A tool transfer device according to a second aspect of the present invention is
Compressed air storage means arranged in the air flow passage for storing compressed air generated by the compressed air generation means, and compressed air generation means disposed between the compressed air generation means and the compressed air storage means. And a check valve for preventing the compressed air in the compressed air storage means from being discharged upstream when the air pressure on the means side is lower than the air pressure in the compressed air storage means. Therefore, when compressed air is no longer supplied from the compressed air generating means to the mover, the air pressure on the compressed air generating means side becomes lower than the air pressure in the compressed air storing means, and the compressed air storage is performed by the check valve. It is possible to prevent the compressed air stored in the means from being discharged to the compressed air generating means side, and to supply the compressed air stored in the compressed air storage means to the mover.

A tool transfer device according to a third aspect of the present invention is
The stator is arranged above the table, the tool is composed of a nozzle for sucking and mounting an electronic component, and the electronic component sucked by the nozzle with respect to the substrate placed on the table I am trying to wear. Therefore, in order to mount the electronic component sucked or mounted by the nozzle at a desired position on the substrate placed on the table, compressed air is moved while the mover provided with the nozzle is moved with respect to the stator. Is no longer supplied from the compressed air generating means to the mover provided with the nozzle, the pressure value of the compressed air detected by the pressure detecting means becomes equal to or less than a predetermined value, and the mover stopping means causes The mover is stopped with respect to the stator.

Further, the tool transfer device according to claim 4 is
The tool is a processing tool for processing a workpiece. Therefore, compressed air is transferred from the compressed air generating means to the mover during movement of the machining tool with respect to the stator in order to transfer the machining tool to a desired position of the workpiece placed on the table. When the supply is stopped, the pressure value of the compressed air detected by the pressure detecting means becomes equal to or lower than a predetermined value, and the mover stopping means stops the mover with respect to the stator.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments in which the tool transfer device of the present invention is embodied in an electronic component mounting device will be described below with reference to the drawings.

FIG. 2 is an overall perspective view of the electronic component mounting apparatus 1 using the plane linear motor 3 as a linear motor.

The electronic component mounting apparatus 1 is composed of a base 8 having a work table 7 on an upper portion thereof, columns 9 provided at four corners of the base 8, and a ceiling 23 supported by the columns 9. ing.

A platen 6 as a stator is provided on the back surface of the ceiling 23. To the lower part of the platen 6, a mover 2 that can move freely within the area of the platen 6 is magnetically coupled. At the lower part of the mover 2, a mounting head 4 having a nozzle 5 for sucking and mounting an electronic component at the lower end is provided. The mover 2 and the platen 6 form a planar linear motor 3 as a linear motor. At the center of the work table 7, there is provided a conveyor 24 for carrying and carrying out the substrate 82. In addition, in FIG. 2 of the work table 7, a plurality of feeders 81 are provided on the front side of the work table 7 for supplying components with component tapes containing electronic components at a constant pitch.

Next, the structure of the planar linear motor 3 will be described with reference to FIGS. 5 and 6. Four movers 40, 41, 42, 43 are arranged on the bottom surface of the mover 2. The forcers 40, 42 generate thrust in the X-axis direction, and the forcers 41, 43 generate thrust in the Y-axis direction. Is configured to. These forsa 40, 41, 4
The mover 2 moves XY on the platen 6 by the thrust forces of 2, 43.
It can move freely in the axial direction. A blowout port 44 for compressed air is provided on the bottom surface of the mover 2, and the compressed air supplied through the tube 11 is ejected. This allows the mover 2 to move smoothly on the platen 6.

On the other hand, as shown in FIG. 6, the platen 6 has teeth 31 formed on the surface of a steel plate 30 made of a magnetic material at equal intervals in the XY axis directions, and the grooves 32 of the teeth 31 are made of a non-magnetic material. , For example, by filling with an epoxy resin 33. The driving principle of the planar linear motor 3 will be described with reference to FIGS. 6 and 7. FIG. 7 is a cross-sectional view of the forcer 40 shown in FIG. 5 and the platen 6 shown in FIG. The planar linear motor 3 is a PM type linear pulse motor, which is a so-called "soya motor", and is disclosed in Japanese Patent Publication No. 53-73. The forcer 40 is composed of two electromagnets 48 and 49, and the electromagnets 48 and 49 are permanent magnets 50 and 51 and the permanent magnets 50 and 51, respectively.
Magnetic poles 61, 62, 63, 6 respectively arranged at the ends of the
4, 65, 66, 67, 68, and excitation windings 52, 53. The two permanent magnets 50 and 51
The path of the bias magnetic flux generated by the magnetic fluxes generated in and out of the platen 6 side is selected from the magnetic poles 61, 62, 63, 64, 65, 66, 67, 68 by the excitation windings 52, 53. The magnetic poles 61 and 62, 63 and 64, 6
5 and 66 and 67 and 68 are arranged with a shift of τ / 2, respectively, where τ is the pitch of the teeth 31 of the platen 6. Further, the magnetic poles 61 and 63, 65 and 67 are respectively shifted by an integral multiple of τ, and the magnetic poles 61 and 65 are arranged so as to be offset by τ / 4.

Here, for example, when the excitation winding 52 is energized in the direction shown in FIG. 7, the magnetic forces are doubled at the magnetic poles 61 and 63 and canceled at the magnetic poles 62 and 64. Stop at position (a). At this time, the magnetic force of the electromagnet 49 is well balanced.

Next, as shown in FIG. 8B, the excitation winding 5
When a current flows in the direction shown in FIG. 3 in FIG. 3, the magnetic force is canceled by the magnetic poles 66 and 68 of the electromagnet 49 and the magnetic force is doubled at the magnetic poles 65 and 67, so that half the tooth width, that is, τ / 4.
Only the forsa 40 moves to the left.

Next, as shown in FIGS. 8 (c) and 8 (d), the force is applied to the electromagnets 48 and 49 in the opposite direction to that shown in FIGS. Move / 4 to the left.

As described above, the forcer 40 is moved by passing the rectangular wave current through the electromagnets 48 and 49. At this time, a smooth thrust can be obtained by making the current sinusoidal.

The mover 2 tries to come into close contact with the platen 6 by the forcer 40, but compressed air is blown out from the blowout port 44 provided on the bottom surface of the mover 2 shown in FIG. A minute gap 45 shown in FIG. At this time, the groove portion 70 of each magnetic pole is filled with non-magnetic material, for example, epoxy resin, like the groove portion 32 of the platen 6, and then flat polished with each magnetic pole to form a flat surface without a step and to obtain the static pressure air. Form the bearing. This allows the mover 2 to move smoothly while maintaining a minute gap 45 of 10 to 20 μm between the mover 2 and the platen 6. Since the gap 45 is so small, the mover 2 and the platen 6 are required to have a high shape accuracy, and the compressed air to be supplied needs clean air with less dust and oil mist.

Next, referring to FIG. 3, the planar linear motor 3
The compressed air supply path to the mover 2 will be described.

Compressor 2 as compressed air generating means
The compressed air supplied from 2 is guided to the filter 19 via the tube 21. Here, the connector 20 is provided to freely connect and disconnect the tube 21 and the filter 19. The filter 19 removes dust and oil mist in the compressed air supplied to the mover 2. next,
The compressed air is decompressed by the regulator 18 to about 1.5 to 3 atm, which is the pressure required to supply the mover 2, and enters the accumulator 13 as compressed air storage means via the check valve 14. The regulator 18 is provided with a pressure switch 16 as pressure detecting means that opens and closes by the pressure of the compressed air after depressurization, and is connected to a control device 17 that controls the entire electronic component mounting apparatus 1.

On the downstream side of the accumulator 13,
A valve 12 is provided for sending or stopping compressed air to the mover 2 via the tube 10.

Incidentally, the compressor 22, the tube 21, the connector 20, the filter 19, the regulator 18, the check valve 14, the accumulator 13, the valve 12, and the tube 10.
The series of flow of the above functions as an air flow passage.

Next, the electronic component mounting apparatus 1 of the present embodiment
The electric circuit configuration of will be described with reference to FIG.

The control device 17 has a ROM 72 in which a program for controlling the movement of the mover 2 and the like are stored, and a RAM for temporarily storing variables and the like used in the program.
73 and I / O 74 as an input / output interface
And a system bus 80 for connecting the above respective components
And a CPU 71 that controls the electronic component mounting apparatus 1 according to a program stored in the ROM 72. Further, the I / O 74 is provided with the pressure switch 16 and the mover 2, a nozzle drive valve 75 for moving the nozzle 5 up and down by an air cylinder or the like, and that the nozzle 5 reaches the upper end and the lower end. A nozzle position sensor 76 for detecting, a vacuum generator 77 for making the inside of the nozzle 5 into a vacuum state to adsorb an electronic component, and a nozzle pneumatic pressure for detecting the vacuum state in the nozzle 5 by the vacuum generator 77. A detector 78 and a conveyor control device 79, which will be described later, for driving and stopping the conveyor 24 are connected.

The conveyor controller 79 drives the belt to move the substrate 82 to a predetermined position on the work table 7 when the substrate 82 is placed and a power source (not shown) is pressed. When the sensor (not shown) determines that the substrate 82 has reached a predetermined position, the substrate 82 is fixed by an air cylinder (not shown) or the like. The conveyor control device 79 outputs a signal to the I / 074 of the control device 17 when the fixing of the substrate 82 is completed. On the other hand, when the mounting of the electronic component on the board 82 is completed, the control device 17 outputs a signal to the conveyor control device 79 via the I / O 74. Then, the conveyor control device 79 releases the fixation of the board 82, carries out the board 82 from the electronic component mounting apparatus 1, and carries the next board into the electronic component mounting apparatus 1.

Next, the electronic component mounting apparatus 1 of this embodiment
The operation will be described with reference to the flowchart of FIG.

First, the power of the compressor 22 is turned on, and compressed air is stored in the accumulator 13 via the tube 21, the filter 19 and the regulator 18.
After that, when the valve 22 is opened, the compressed air stored in the accumulator 13 is ejected from the blowout port 44 of the mover 2 via the tube 10, and the mover 2 floats slightly above the platen 6. Further, the conveyor 24 is driven by turning on a power source (not shown) to carry in the substrate 82.

After that, the control device 17 (not shown) is turned on, and the mounting data for mounting the electronic parts input by the input means such as a keyboard is stored in the RAM 73.
When a start key (not shown) is pressed, the program shown in FIG. 1 is started.

In the program, first, it is checked whether or not the compressed air has become equal to or lower than the pressure set by the pressure switch 16 (step 100, hereinafter, step is represented by S). When the compressed air exceeds the pressure value set by the pressure switch 16 (NO in S100), the CPU 71 receives the fixing completion signal of the substrate 82 from the conveyor control device 79 via the I / 074 as described above. It is determined whether or not there is (S102). When the fixing of the substrate 82 is completed (YES in S102), the electronic component is sucked as shown below (S104). First, the mover 2 is moved to the feeder 81, a signal is output to the nozzle drive valve 75, and the nozzle 5 is lowered. When the nozzle 5 reaches the lower end (a signal is input by the nozzle position sensor 76), a signal is output to the vacuum generator 77 to adsorb the electronic component. Whether or not the suction of the electronic component is completed is determined by the input signal from the nozzle air pressure detector 78. Then, the nozzle 5 is raised via the nozzle drive valve 75. Whether or not the ascent of the nozzle 5 is completed is determined by an input signal from the nozzle position sensor. As a result, the electronic component is adsorbed by the nozzle 5.

Next, when the CPU 71 determines that the suction of the electronic components is completed, it outputs a pulse to the mover 2 to move the mover 2 to a desired position. Then
The nozzle 5 moves to the mounting position (S106). After that, a signal is output again to the nozzle drive valve 75 so as to lower the nozzle 5, and a signal input indicating that the nozzle 5 has reached the lower end from the nozzle position sensor 77 is awaited. Further, the vacuum generator 77 is caused to output a stop signal. Then, the electronic component sucked by the nozzle 5 is mounted on the substrate 82 (S108). When the mounting of one electronic component is completed, it is determined whether or not the mounting is completed for all the electronic components of the mounting data stored in the RAM 73 (S110), and if there is an electronic component not yet mounted (S110). NO), the process proceeds to S100. On the other hand, when it is determined that the mounting of all the electronic components is completed (YES in S110), a signal for releasing the fixation of the substrate 82 is output to the conveyor control device 79 (S112). Then, the conveyor control device 79 releases the fixation of the board 82 and carries out the board 82. After that, the CPU 71 shifts the processing to S100.

In step S100, if the compressed air is no longer supplied to the mover 2 because the tube 21 breaks or bends while the mover 2 is moving, or the tube 21 comes off from the connector 20 of the filter 19, the regulator Compressed air in the pipe between 18 and the check valve 14 flows backward from the regulator 18. Then, the pressure immediately after the regulator 18 drops, and when the pressure switch 16 drops below a predetermined value, the pressure switch 16 opens, and the signal of the pressure switch 16 is sent to the CPU via the I / O 74.
71 is input. Then, the CPU 71 determines that the pressure value of the compressed air has become equal to or lower than a predetermined value (S1
If YES at 00), the output of the pulse to the mover 2 is stopped (S114). After that, the process proceeds to S100.

At this time, the pressure in the upstream of the regulator 18 becomes lower than that in the accumulator 13, the check valve 14 operates, and the compressed air in the accumulator 13 does not leak to the regulator 18 side but flows to the planar linear motor 3 side. become. As described above, even if the supply of the compressed air from the compressor 22 is stopped, the compressed air is stored in advance in the accumulator 13, so that the accumulator 13 is stored.
The compressed air can be supplied to the mover 2 from the. still,
The processing step of S114 functions as a stopping unit that stops the mover 2 when the pressure value detected by the pressure switch 16 becomes equal to or lower than a predetermined value.

As is clear from the above description, in the tool transfer device of this embodiment, compressed air is compressed by the compressor 2
2 is no longer supplied to the mover 2, the pressure switch 1
The pressure value of the compressed air detected by 6 becomes equal to or less than a predetermined value, the tool provided on the mover 2 is stopped by the controller 17, and the compressed air stored in the accumulator 13 is moved by the check valve 14 by the check valve 14. Since the flow moves to the 2 side, the mover 2 and the platen 6 do not come into contact with each other until the mover 2 stops, thereby preventing damage to each other.

The present invention is not limited to the embodiments described in detail above, and various modifications can be made without departing from the spirit of the invention.

For example, in the present embodiment, air was supplied to the linear pulse motor (LPM), but if the motor is a floating motor using an air bearing, a linear direct current motor (LDM), a linear induction motor ( It is also possible to replace it with a LIM) or a linear synchronous motor (LSM).

Further, in order to send or stop the compressed air to the mover 2 through the tube 10, the manual valve 12 is used in the present embodiment, but a solenoid valve is used instead and the controller 17 is used. It may be controlled.

Further, in the present embodiment, the compressed air is stored by using the accumulator 13, but when the mover 2 is immediately stopped, the accumulator 13 and the check valve 14 may be omitted.

Further, in the present embodiment, when the air pressure of the compressed air becomes equal to or lower than the value set by the pressure switch 16, the mover 2 is immediately stopped (S114).
After moving the mover 2 to a safe position, S114 may be changed to stop it. In addition, in such a configuration, the mover 2 must be levitated by the compressed air while the mover 2 is moved to a safe position.
Accumulator 13 and check valve 14 are required.

Further, in the tool transfer device of this embodiment,
Although the signal from the pressure switch 16 is confirmed after mounting the electronic component, the signal of the pressure switch 16 may be always confirmed in the interrupt process. In this case, in the interrupt process, when the pressure decrease signal is input from the pressure switch 16 to the CPU 71, the movement of the mover 2 is immediately stopped. In addition, it is stopped after being moved to a predetermined position.

Further, although the pressure switch 16 is used as the pressure detecting means in the present embodiment, a pressure sensor may be used. In this case, a predetermined pressure value is stored in the RAM 73, and in S100, the pressure value is compared with the pressure value obtained from the pressure sensor.

Further, in the tool transfer device of this embodiment,
Although the one embodied in the electronic component mounting apparatus has been described, it may be used in another machine tool. For example, the tool provided on the mover 2 is composed of a processing tool such as a drill or a tap, and the work piece is mounted on the work table. Further, the tool may be a board inspection device that inspects an arrangement state of electronic components mounted on the board.

[0045]

As is apparent from the above description, according to the tool transfer device of the first aspect of the present invention, when compressed air is no longer supplied from the compressed air generating means to the mover, the pressure is reduced. The pressure value of the compressed air detected by the detection means becomes equal to or less than a predetermined value, and the tool provided on the mover is stopped by the mover stopping means, so that the compressed air is not supplied while the tool is moving. Even if the mover and the stator do not move while maintaining contact with each other, damage to the mover and the stator can be prevented.

The tool transfer device according to claim 2 is
When compressed air is no longer supplied from the compressed air generating means to the mover provided with the tool, the air pressure on the compressed air generating means side becomes lower than the air pressure in the compressed air storing means, and the check valve causes In order to prevent the compressed air stored in the compressed air storage means from being discharged to the compressed air generating means side, the compressed air stored in the compressed air storage means is supplied to the mover, and The time until contact with the stator can be extended, and the mover can be moved to a safe position in the meantime.

A tool transfer device according to a third aspect of the present invention is
While the mover provided with the nozzle is moved with respect to the stator to move the electronic component sucked or attached by the nozzle to a desired position of the substrate placed on the table, the compressed air is When the compressed air is no longer supplied from the compressed air generating means to the mover provided with the nozzle, the pressure value of the compressed air detected by the pressure detecting means becomes a predetermined value or less, and the stator is stopped by the mover stopping means. On the other hand, in order to stop the mover, it is particularly effective to prevent damage to the mover and the stator in an apparatus that requires extremely high-accuracy positioning such as mounting an electronic component.

Further, the tool transfer device according to claim 4 is
Compressed air is supplied from the compressed air generating means to the mover during movement of the machining tool with respect to the stator in order to transfer the machining tool to a desired position of a workpiece placed on the table. When it disappears, the pressure value of the compressed air detected by the pressure detecting means becomes equal to or less than a predetermined value, and the mover stopping means stops the mover with respect to the stator. It is possible to obtain an effect that it is possible to prevent the contact from moving while being in contact with.

[Brief description of drawings]

FIG. 1 is a flowchart showing an operation of a stop device for a planar linear motor according to the present embodiment.

FIG. 2 is an overall view in which the tool transfer device according to the present embodiment is embodied in an electronic component mounting device.

FIG. 3 is a block diagram showing a configuration of a tool transfer device according to the present embodiment.

FIG. 4 is a block diagram showing an electrical circuit configuration of the electronic component mounting apparatus of the present embodiment.

FIG. 5 is a perspective view of a mover of the planar linear motor according to the present embodiment.

FIG. 6 is a perspective view of the platen of the planar linear motor according to the present embodiment.

FIG. 7 is a cross-sectional view of a mover and a platen of the planar linear motor according to the present embodiment.

FIG. 8 is a diagram for explaining the operating principle of the planar linear motor of the present embodiment.

[Explanation of symbols]

 1 Stopping device 2 Mover 3 Planar linear motor 5 Nozzle 6 Platen 13 Accumulator 14 Check valve 16 Pressure switch 17 Control device

Claims (4)

[Claims] 1. A work table and compressed air generated by compressed air generating means are supplied to a mover through an air flow passage to levitate the mover with respect to a stator, and the mover is in a floating state. In a tool transfer device for moving the tool to a desired position by the linear motor, the tool is provided in the air flow passage, and the compressed air is provided in the compressed air. And a mover stopping means for stopping the mover when the pressure value detected by the pressure detecting means becomes equal to or less than a predetermined value. Tool transfer device. 2. A compressed air storage means arranged in the air flow passage for storing compressed air generated by the compressed air generating means, and arranged between the compressed air generating means and the compressed air storage means. And a check valve for preventing the compressed air in the compressed air storage means from being discharged upstream when the compressed air generation means side has a lower air pressure than the compressed air storage means. The tool transfer device according to claim 1. 3. The stator is arranged above the table, the tool is constituted by a nozzle for adsorbing and mounting an electronic component, and the substrate is placed on the table and is adsorbed by the nozzle. The tool transfer device according to claim 1, wherein the electronic component is mounted. 4. The tool transfer device according to claim 1, wherein the tool is a processing tool that processes a workpiece.