JPH09130093A - Surface mounter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively lighten the shock at the time of lifting of a nozzle member, with compact constitution. SOLUTION: This surface mounter is so arranged that a nozzle member 20 is mounted freely of ascent and descent on a head unit 5 and is driven by an air cylinder 33, and the air cylinder 25 is provided with cushion mechanisms which decelerate he shifting speed of a piston 33 right before the ascent end or right before the decent end, respectively, at the time of ascent and descent of the piston 33. The cushion mechanism is composed of small-diameter parts 38a and 38b provided above and below the piston 33, seal members 39a and 39b arranged above and below those, inner frame parts 40a and 40b provided in the vicinity of top and bottom of pressure chambers 34 and 35, and sub ports 41a and 41b making each pressure chamber 34 and 35 and the ports 36 and 37 communicate with each other at the lower end face of the inner frame 40a and the upper end face of the lower inner frame 40b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mounter having a head unit movable over a component supply section and a component mounting section and provided with a nozzle member for adsorbing a component which is driven up and down by an air cylinder. is there.

[0002]

2. Description of the Related Art Conventionally, a head unit, which is movable between a component supply section and a printed circuit board positioned at a predetermined working position, is equipped with a nozzle member for component suction so as to be vertically movable and rotatable. A surface mounter is generally known in which a negative pressure supplied to a member is used to suck an electronic component, and after the component is sucked from a component supply unit, a head unit is moved onto a printed circuit board to mount the component. There is. In this mounting machine, the nozzle member mounted on the head unit is moved up and down by the up-and-down drive means during component pick-up and component mounting.

As the above-mentioned raising / lowering driving means, there are a means for raising and lowering the nozzle member by a servo motor through a ball screw or the like, and a means for raising and lowering the nozzle member by an air cylinder. From the viewpoint of compactness, many mounting machines use an air cylinder to configure a drive system for raising and lowering a nozzle member.

Particularly, in a mounting machine in which a head unit is equipped with a large number of nozzle members from the viewpoint of improving mounting efficiency, it is difficult to provide a servo motor for each nozzle member in terms of space and the like. An air cylinder is effective as a drive means for individually driving the members.

[0005]

By the way, in the mounting machine in which the nozzle member is lifted and lowered by using the air cylinder as described above, the lifting speed of the nozzle member by the air cylinder is substantially constant over the entire lifting stroke. When an attempt is made to increase the ascending / descending speed of the nozzle member in order to shorten the cycle time, the impact force when the nozzle member reaches the descending end position or the ascending end position increases accordingly. Therefore, the impact force applied to the component at the time of suction or the like becomes large, and the component may be displaced from the nozzle member or the component may drop out due to the impact when the nozzle member reaches the rising end position after component suction. Therefore, there is a possibility that the mounting accuracy may be impaired only by increasing the lifting speed of the nozzle member to shorten the cycle time.

[0006] Therefore, in order to reduce the impact when the nozzle member is raised and lowered to shorten the cycle time, for example, a damper member may be provided at the rising end position of the nozzle member to reduce the impact force. However, in this case, a separate damper member needs to be provided, which may lead to an increase in the size and weight of the head unit, which is not necessarily a good measure.

The present invention has been made in order to solve the above problems, and in a nozzle member raising and lowering drive means using an air cylinder, it is possible to effectively reduce the impact when the nozzle member is raised and lowered with a compact structure. The object is to provide a surface mounter capable of

[0008]

SUMMARY OF THE INVENTION The present invention provides a head unit movable between a component supply section and a component mounting section,
In a surface mounter equipped with a nozzle member for adsorbing an electronic component and an air cylinder for driving the nozzle member up and down, the air cylinder includes a piston connected to the nozzle member, and a pair of pressures above and below the piston. And a cylinder having an air supply / exhaust port in each pressure chamber, and at least one pressure chamber of the cylinder has a thin cylinder portion formed on the moving end side of the piston. While the air supply / discharge port is opened at, the piston has a small diameter portion at its axial end portion that can be inserted into the thin cylinder portion of the cylinder. In either case, a sealing means for sealing between the thin cylindrical portion and the small diameter portion when the small diameter portion is inserted into the thin cylindrical portion is provided, and this sealing means is provided to the moving end position of the piston. Before reaching those consisting configured to achieve the seal.

According to this surface mounter, air is supplied to one pressure chamber of the air cylinder, while air is discharged from the other pressure chamber, whereby the piston is moved up and down, whereby the nozzle member is moved. Is driven up and down. When the piston reaches the vicinity of the moving end position during the up-and-down driving of the nozzle member, the small diameter portion of the piston is inserted into the thin cylindrical portion of the cylinder, and a seal member seals between the thin cylindrical portion and the small diameter portion. In this state, air is enclosed between the small diameter portion of the piston and the inner wall of the cylinder. Therefore, until the piston reaches the moving end position from this position, the movement of the piston is slowed down by the cushioning action due to the compression of the air enclosed between the small diameter part of the piston and the inner wall of the cylinder. The impact at the rising end position or the falling end position of the member is mitigated.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 schematically shows an entire surface mounter (hereinafter abbreviated as mounter) according to an embodiment of the present invention. In this figure, a conveyor 2 constituting a transfer line is arranged on a base 1, and a printed circuit board 3 is conveyed on the conveyor 2 and stopped at a predetermined mounting work position. The conveyor 2 is composed of a pair of unit conveyors 2a and 2b arranged in parallel, and one (the upper side in FIG. 1) unit conveyor 2 by a width adjusting mechanism (not shown).
b approaches the other (lower side in FIG. 1) unit conveyor 2a,
Alternatively, they can be separated. With this, it is possible to cope with the change in size of the printed circuit board 3.

On the side of the conveyor 2, a parts supply section 4 is provided.
Is arranged. The component supply unit 4 includes a large number of rows of tape feeders 4a. Each tape feeder 4a is a reel in which small pieces of chip components such as ICs, transistors and capacitors are stored and held at predetermined intervals. In addition, the tape feed-out end is provided with a ratchet type feed mechanism so that the tape is intermittently fed out as parts are picked up by a head unit 5 described later.

A head unit 5 for mounting components is installed above the base 1, and the head unit 5 is mounted on the head unit 5.
Can move in the X-axis direction (direction of the conveyor 2) and in the Y-axis direction (direction orthogonal to the X-axis on the horizontal plane).

That is, a pair of fixed rails 7 extending in the Y-axis direction and a ball screw shaft 8 rotatably driven by a Y-axis servomotor 9 are arranged on the base 1, and the fixed rails 7 are mounted on the fixed rail 7. A head unit support member 11 is arranged in the head unit, and a nut portion 12 provided on the support member 11 is screwed onto the ball screw shaft 8. The support member 11 is provided with a guide member 13 extending in the X-axis direction and a ball screw shaft 14 (shown in FIG. 3) driven by an X-axis servomotor 15. The unit 5 is movably held, and a nut portion 16 (shown in FIG. 3) provided on the head unit 5 is screwed to the ball screw shaft 14. The ball screw shaft 8 is rotated by the operation of the Y-axis servo motor 9 to move the support member 11 in the Y-axis direction, and the ball screw shaft 14 is rotated by the operation of the X-axis servo motor 15, thereby causing the head unit to rotate. 5 moves in the X-axis direction with respect to the support member 11.

A component recognition camera 17 is arranged at a predetermined position on the base 1. In the illustrated example, the component recognition camera 17 is arranged between the fixed unit conveyor 2a and the component supply unit 4 on the side thereof, and the head unit 5 is provided.
The component sucked by the nozzle member 20 described later is imaged by the camera 17, and the component recognition process based on the image is used to determine the component suction state.

2 to 5 show the structure of the head unit 5. In these figures, the head unit 5 is provided with nozzle members 20 for sucking components, and in this embodiment, eight nozzle members 20 are arranged in a state of being aligned in the X-axis direction. Further, the head unit 5 includes an elevating and lowering drive mechanism for elevating and lowering each of the nozzle members 20, and a rotation drive mechanism for rotating each of the nozzle members.
Each nozzle member 20 is provided with a negative pressure supply system or the like that supplies a negative pressure for component suction.

The elevating and lowering drive mechanism includes a single servo motor 2 for vertically moving all the nozzle members 20 simultaneously.
1 and a predetermined number (8) of air cylinders 25 for individually raising and lowering each nozzle member 20 by a fixed stroke,
By using the servo motor 21 and the air cylinder 25 together, each nozzle member 20 is configured to be moved up and down between a predetermined raised position and a predetermined lowered position. Further, the rotation drive mechanism has one rotation servomotor 60, and the servomotor 60 is configured to rotate each nozzle member 20 via the power transmission means.

To describe the structure of the head unit 5 more specifically, a housing 22 holding the nozzle member 20 and the air cylinder 25 is attached to the head unit body 5a so as to be vertically movable, and A vertical movement servomotor 21 is mounted on the upper side, and the servomotor 21 vertically moves the housing 22 via a ball screw 23.

Each of the nozzle members 20 has a hollow nozzle shaft 20a and a nozzle holder 20 attached thereto.
The nozzle member 20 is attached to the housing 22 via a nozzle guide 26 so as to be vertically movable and rotatable. That is, the nozzle guide 2 is attached to the housing 22.
6 is rotatably mounted, and the nozzle shaft 20a is vertically movably fitted to the nozzle guide 26.

The nozzle holder 20b is movable relative to the nozzle shaft 20a by a constant stroke in the axial direction, and is attached to the nozzle shaft 20a while being urged toward the lower end by a spring 27. That is, the nozzle holder 20b is replaced by the nozzle shaft 2
By making it possible to elastically move in the axial direction with respect to 0a, the tip of the nozzle collides with the component when sucking and mounting the component, or the suction component and the printed circuit board 3 when mounting the component.
It is designed so that the impact caused by the collision with can be mitigated.

A bearing 28 is fixed to a substantially middle portion of the nozzle shaft 20a, and a spring 29 is attached to a lower portion of the nozzle shaft 20a. The spring 29 allows the nozzle shaft 20a to move upward through the bearing 28. I am biased. Between the bearing 28 and the spring 29, as shown in FIG.
A washer 30 that can rotate relative to 0 is interposed, and a steel ball 31 is rotatably held between the washer 30 and the inner ring portion of the bearing 28.

The outer ring portion of the bearing 28 is slidably in contact with a vertically extending guide portion 22a formed on the housing 22 when the nozzle shaft 20a moves up and down, whereby the nozzle shaft 20a swings when moving up and down. Is being prevented.

A descending end sensor 32 is attached to the housing 22 at a position facing the nozzle shaft 20a of each nozzle member 20, and the sensor 32 is attached to the bearing 28 as the nozzle shaft 20a descends. By detecting the nozzle shaft 20a
Has been detected to have reached the descending end position.

Above each of the nozzle member installation locations on the front side of the housing 22, the air cylinders 25 are placed.
An air supply / discharge system for each air cylinder 25 is provided, and the upper end of the nozzle shaft of each nozzle member 20 projects into the corresponding air cylinder 25. As described later in detail, the air supply / discharge system has an air cylinder drive solenoid valve 44 for switching supply / discharge of air to / from each air cylinder 25.
The solenoid valve 44 has an elevating / lowering drive speed varying means for changing the ascending / descending speed of the air cylinder 25 by adjusting the air discharge speed using the speed control valves 49, 50, etc. Connected to the source.

Each air cylinder 25 has a piston 33 therein, and pressure chambers 34 and 35 above and below the piston 33, respectively.
35 is connected to the passage of the air supply / discharge system via ports 36 and 37. When the air is discharged from the lower pressure chamber 35 while the air is supplied to the upper pressure chamber 34, the piston 33 descends, and conversely, the air is supplied from the upper pressure chamber 34 to the lower pressure chamber 35. The piston 33 moves up when the is discharged.

At the lower end of the piston 33, a cylindrical sleeve 33a longer than the lifting stroke of the piston 33 is provided.
Is integrally provided, and the upper end portion of the nozzle shaft of the nozzle member 20 which is projected into the air cylinder 25 is rotatably inserted in the sleeve 33a.

Further, the air cylinder 33 is provided with a cushion mechanism for decelerating the moving speed of the piston 33 immediately before the ascending end and immediately before the descending end when the piston 33 is moved up and down. This cushion mechanism uses the piston 3
3. Small diameter portions 38a, 38b provided on the upper and lower portions of 3, respectively
And sealing members 39a and 39b arranged in the upper and lower parts thereof and the pressure chambers 34 and 3 respectively.
5 has inner frame portions (thin tubular portions) 40a, 40b provided near the upper end portion and the lower end portion of the inner frame portion 5, respectively.
In the inner wall 40b, the ports 36 and 37 are opened, and sub-ports 41a and 41b, which are ultrafine passages that communicate the pressure chambers 34 and 35 with the ports 36 and 37, are provided in the upper inner frame portion 40a. The lower end surface and the upper end surface of the lower inner frame portion 40b are opened.

Then, in order to lower the nozzle member 20, the piston 33 in the air cylinder 25 is lowered from the state of being in the rising end position as shown in FIG. 7 (a), and as shown in FIG. 7 (b), in the vicinity of the lower end. When reaching the lower side, the sealing member 39b provided on the lower small-diameter portion 38b moves to the inner frame portion 4 on the lower side.
0b, and in this state, the small diameter portion 38b of the piston 33
A cushion chamber 42 is defined between the cylinder and the inner wall of the cylinder. Then, from the position of the piston 33 to the lower end position shown in FIG. 7C, the air trapped in the cushion chamber 42 is compressed and gradually discharged through the sub port 41b. The action slows down the descent of the piston 33.

On the contrary, in order to raise the nozzle member 20, in the air cylinder 25, the piston 33 is raised from the lower end position shown in FIG.
When reaching the vicinity of the ascending end as described above, the seal member 39a provided on the upper small diameter portion 38a is brought into sliding contact with the upper inner frame portion 40a, whereby the cushion chamber is provided between the small diameter portion 38a of the piston 33 and the cylinder inner wall. 43 is defined. Then, until the piston 33 reaches the rising end position shown in FIG. 8C, the air trapped in the cushion chamber 42 is compressed and gradually discharged through the sub-port 41a. The rise of the piston 33 is slowed down.

FIG. 9 shows an air supply / discharge system for the air cylinder 25. As shown in the figure, between the air cylinder driving solenoid valve 44 and the air cylinder 25, a lower pressure chamber air passage 45 communicating with the lower pressure chamber 35 of the air cylinder 25, and an upper pressure chamber 34. And an upper pressure chamber air flow path 46 communicating with the above. The solenoid valve 44 connects the air passage 45 for the lower pressure chamber to the air supply source 51, and the air passage 4 for the upper pressure chamber.
6 is opened to the atmosphere via the air exhaust flow passage 47, etc. (described later), and the upper pressure chamber air flow passage 46 is connected to the air supply source 51 and the lower pressure chamber air flow is connected. The passage 45 can be switched to a descending drive state in which it is opened to the atmosphere via the air exhaust passage 47 and the like.

Further, as an ascending / descending driving speed varying means, an air exhaust passage 47 connected to the solenoid valve 44 is provided.
And a speed control flow path 48, which is connected to the air exhaust flow path 47 via an operation speed switching valve 52 and has the other end open to the atmosphere. Speed control flow path 48
Is a high-speed operation channel 49 having a high-speed lifting diaphragm 49a.
And a low-speed operation flow path 50 having a low-speed lifting diaphragm 50a
The flow paths 49 and 50 are provided in parallel, and the aperture opening of the high-speed lifting diaphragm 49a is set to be relatively larger than the throttle opening of the low-speed lifting diaphragm 50a. ing.

Therefore, the solenoid valve 44 is switched from the ascending drive state to the descending drive state and the piston 33
If the operation speed switching valve 52 is off (state shown in the drawing) when the air pressure is lowered, the air in the lower pressure chamber 35 is discharged through the air exhaust flow path 47 and the high-speed operation flow path 49, thereby achieving high speed. When the operation speed switching valve 52 is turned on, the air in the lower pressure chamber 35 is discharged through the low speed operation flow passage 50, so that the low speed operation is performed. Further, when the operation speed switching valve 52 is off when the solenoid valve 44 is switched from the descending drive state to the ascending drive state and the piston 33 rises, the upper pressure chamber 34
Is discharged through the air exhaust flow path 47 and the high-speed operation flow path 49 to perform a high-speed rise. If the operation speed switching valve 52 is on, the air in the upper pressure chamber 34 is for low-speed operation. As it is discharged through the flow path 50, a low speed rise is performed.

By the way, the solenoid valve 44 and the operation speed switching valve 52 are controlled by a control unit 55 provided in the mounting machine. The control unit 55 uses the control of the vertical movement servomotor 21 and the air cylinder 25 together to move the nozzle member 20 up and down when the component is sucked from the component supply unit 4 and mounted on the printed circuit board 3. Control of the servo motor 21,
The air cylinder 25 is controlled by controlling the solenoid valve 44 and the operation speed switching valve 52. At this time, the operation sequence of the servo motor 21 and the air cylinder 25 and the ascending / descending driving speed of the air cylinder 25 are selected according to the type of the electronic component attracted to the nozzle member 20. That is, the information about various electronic components is stored in advance in the storage unit 56 in the control unit 55, and the information of the processing target component (electronic component sucked by the nozzle component) is read from the storage unit 56, and In response, a lifting control mode suitable for the processing target component is selected from among various lifting control modes described below, and the servo motor 21 and the air cylinder 2 are selected accordingly.
5 is controlled.

As shown in FIG. 5, the housing 22 further includes the rotation servomotor 60, pulley 61, and
A drive shaft 64 that interlocks with the servo motor 60 via a speed reduction mechanism including a belt 62 and a belt 63 is provided, and a pulley 65 provided on the drive shaft 64 and each nozzle member 20.
A rotation transmission belt 67 is wound around a pulley 66 provided on the nozzle 66, and each of the nozzle members 20 is rotatably driven by the servomotor 60 via the reduction mechanism, the drive shaft 64, and the rotation transmission belt 67. It has become.

Further, the head unit 5 is provided with a vacuum generator 70 for supplying a negative pressure to each of the nozzle members 20, which is disposed above the head unit body 5a. . Then, the negative pressure introducing portion at the upper end of the air cylinder 25 is connected to the vacuum generator 70 via a flexible pipe and a valve (not shown) so that the inside of the piston 33 of the air cylinder 25 is passed. A negative pressure supply / discharge system is configured so that negative pressure is supplied to the nozzle member 20. Since the upper end of the nozzle shaft 20a of the piston 33 and the nozzle member 20 is rotatably connected to the piston 33, there is concern about the sealing property between these members during negative pressure supply. If the O-ring is press-fitted in order to secure the sealing property of No. 1, the rotational resistance of the nozzle shaft 20a increases, which is inconvenient. However, as described above, the piston 26
A sleeve 33a longer than the elevating stroke of is formed integrally with the piston 33, and the nozzle shaft 20a is connected to the piston 33 via this sleeve 33a, so that the sealing property between the piston 33 and the nozzle member 20 is secured. And the rotation resistance is reduced.

By the way, in the mounting machine, as shown in FIG. 4, a negative pressure from the port 36, the upper inner frame portion 40a and the vacuum generator 70 is provided in the upper component 71 which constitutes the upper end of the air cylinder 25. An introduction portion and the like are integrally provided, and the upper constituent member 71 is fitted into the cylinder portion of the air cylinder 25 and is fixedly fastened to the housing 22 with screws or the like, and the nozzle guide 26 that holds the nozzle member 20 is also provided. The plate member 7 is inserted into the inside of the housing 22 from below and is attached by screws or the like.
It is locked by 2. Thereby, the nozzle member 20
Also, maintainability of the air cylinder 25 is ensured.

That is, in the above mounting machine, the sleeve 33
Since the nozzle shaft 20a is simply inserted into a, the upper component 71 is removed to open the upper part of the air cylinder 25, and the piston 33 is pulled out upward to take out only the piston 33 for replacement or repair. Further, by removing the plate member 72, the nozzle guide 26 and the nozzle member 20 can be taken out from the housing 22 and replaced. Therefore, the piston 33 and the nozzle member 20 that are relatively susceptible to wear and changes over time can be easily removed and replaced individually.

Reference numeral 73 is a camera for recognizing the fiducial mark provided on the printed circuit board 3, which is attached to one side of the head unit body 5a.

Next, the mounting operation by the mounting machine will be described.

When the mounting operation is started, first, the head unit 5 is arranged above the component supply section 4, and the air cylinder 2 corresponding to the nozzle member 20 which should pick up the component.
5, the air is discharged from the lower pressure chamber 35 while the air is supplied to the upper pressure chamber 34, and the vacuum generator 7
The negative pressure generated at 0 is applied to the nozzle member 2 at a predetermined timing.
It is supplied within 0. As a result, the piston 33 is lowered, and the sleeve 33a is moved to the bearing 2 via the retaining ring or the like.
By pressing 8 downward, the piston 33 and the nozzle shaft 20a are integrally displaced to the descending end position, and the components are sucked. In addition to the operation of the air cylinder 25 as described above, the vertical movement servo motor 21 is operated to adjust the lowering end position.

Thereafter, the supply / discharge of air to / from the air cylinder 25 is switched to supply air to the lower pressure chamber 35 and discharge air from the upper pressure chamber 34, thereby raising the piston 33. At the same time, the urging force of the spring 29 causes the nozzle shaft 20a to follow the piston 33 and be raised to the rising end position.

At this time, the air cushion action of the cushion mechanism provided in the air cylinder 25 slows down the rising of the nozzle member 20 near the rising end position, whereby the nozzle member 20 reaches the rising end position. The shock is alleviated. Therefore, it is possible to effectively prevent the suction component from being displaced or dropped due to an impact when the rising end position is reached.

By performing the component suction operation as described above for each nozzle member 20, the component is sequentially sucked by each nozzle member 20, and if possible,
The components are simultaneously sucked by the plurality of nozzle members 20.

When the removal of the components from the component supply unit is completed, the head unit 5 is moved to above the printed circuit board 3, and the nozzles are activated by the operation of the vertical movement servo motor 21 and the air cylinder 25 as in the case of the component adsorption. The member 20 is moved up and down, and the negative pressure supply to the nozzle member 20 is cut off at the timing when the nozzle member 20 reaches the lower end, whereby the component is mounted on the printed circuit board 3. At this time, the nozzle member 20 is rotated by driving the rotation servomotor 60 before or after the nozzle member 20 is lowered, and thereby the components are positioned in the rotational direction.

Nozzle member 2 for mounting such components
Even in the lowering operation of 0, the cushion mechanism of the air cylinder 25 slows down the lowering of the nozzle member 20 in the vicinity of the lowering end, and the impact at the lowering end position of the nozzle member 20 is alleviated. Etc. are prevented.

In the positioning in the rotational direction when mounting the components, when the nozzle member 20 is rotated with the nozzle member 20 lowered as described above, the spring 2 is used.
Since the axial biasing force acts on the nozzle shaft 20a via the bearing 28 by compressing 9,
There is a concern that this may act as a rotational resistance of the nozzle member 20. However, in the mounting machine, as described above, the steel ball 31 is rotatably held between the upper end of the spring 29 and the bearing 28 via the washer 30.
As a result, the relative rotation between the bearing 28 and the spring 29 can be easily performed, so that even when the spring 29 is compressed, its urging force can act as rotation resistance of the nozzle member 20. Suppressed.
Therefore, even when the nozzle member 20 is lowered, the nozzle member 20 is smoothly rotated and the positioning in the rotational direction is accurately performed.

When a component is adsorbed by each nozzle member 20 of the head unit 5, the head unit 5 is moved, the nozzle member 20 is rotated, and the nozzle member 20 is moved up and down continuously. The components attracted to each nozzle member 20 are sequentially mounted on the printed circuit board 3.

By the way, in the above component suction / mounting operation, the nozzle member 20 is lifted / lowered in a mode selected from various lift / lower control modes shown in FIGS. Done.

That is, FIG. 10 shows the elevation control mode when the target component is a standard chip component. At the time of picking up parts, as shown in FIG. 3A, the servo motor 21 is first driven so that the distance between the tip of the nozzle and the upper surface of the target part corresponds to the operating stroke of the air cylinder 25. The height position of the member is adjusted (step S11). Next, the nozzle member 20 is lowered at a high speed by driving the air cylinder 25, that is, the air cylinder driving solenoid valve 44 is switched to the descending driving state and the operation speed switching valve 52 is turned off. The piston 33 is operated at a high speed in the descending direction (step S12). And the nozzle member 20
When reaches the descending end position and the nozzle tip comes into contact with the target component, the component is adsorbed by the negative pressure supplied to the nozzle member 20 (step S13). Then, the air cylinder 2
5, the nozzle member 20 is lifted at high speed by the drive of 5,
That is, the solenoid valve 44 is switched to the ascending drive state, and the operation speed switching valve 52 is kept on, whereby the piston 33 is moved in the ascending direction at a high speed (step S14).

Even when the components are mounted, the height position of the nozzle member 20 is first adjusted by driving the servo motor 21 (step S16), as shown in FIG.
The nozzle member 20 is lowered at a high speed by driving the air cylinder 25 (step S17). Then, when the nozzle member 20 reaches the lower end position, the negative pressure supply is stopped and the component is mounted on the printed circuit board 3 (step S18), and then the nozzle member 20 is driven by driving the air cylinder 25.
Is raised at high speed (step S19).

In this mode, the nozzle member 2 is moved by the air cylinder 25 after the height position is adjusted by driving the servo motor 21 both when the component is picked up and when the component is mounted.
The cycle time is shortened because the descent of 0 is performed at a high speed, and the nozzle member 20 is raised by the air cylinder 25 after being sucked and attached at a high speed. in this case,
The suction force of the nozzle member 20 sufficiently acts on the standard chip component, and the air cushion function of the cushion mechanism is exerted, so that the nozzle member 2
Even if 0 is moved up and down at high speed, parts will not fall off or shift.

Next, FIG. 11 shows a case where the target component is a specially shaped component (for example, a component having irregularities, grooves, etc. on its upper surface) in which the suction force of the nozzle member 20 is easily reduced, or a component having a large weight. The control mode is shown. At the time of picking up components, the height position of the nozzle member 20 is first adjusted by driving the servo motor 21 (step S21), and then the nozzle member 20 is driven by driving the air cylinder 25, as shown in FIG. Is performed at a low speed, that is, the solenoid valve 44 is switched to the descending drive state and the operation speed switching valve 52 is turned on.
The piston 33 is operated at a low speed in the descending direction (step S22). Then, the nozzle member 20 reaches the descending end position and the component is sucked (step S23). Then, the nozzle member 20 is lifted at a low speed by driving the air cylinder 25, that is, the solenoid valve 44 is switched to the lift driving state and the operation speed switching valve 52 is kept on, so that the piston 33 is lifted. Direction is operated at a low speed (step S24).

On the other hand, at the time of component mounting, the height position of the nozzle member 20 is adjusted by first driving the servo motor 21 as shown in FIG. 7B (step S25).
Next, the nozzle member 20 is lowered at a low speed by driving the air cylinder 25 (step S26), and when the lower end position is reached, the component is mounted on the printed circuit board 3 (step S26).
27), and then the nozzle member 20 is raised at a low speed by driving the air cylinder 25 (step S2).
8).

Further, in FIG. 12, the target component is, for example, Q.
The lift control mode in the case of a component such as FP that requires particularly high precision mounting is shown. At the time of picking up components, as shown in FIG. 3A, first, the nozzle member 20 is lowered at a low speed by driving the air cylinder 25 (step S31), whereby the nozzle member 20 is moved to a position close to the target component. After the descent, the servo motor 21 is driven to gently descent to the position where the nozzle member 20 comes into contact with the component (step S32). Then, the components are adsorbed (step S33), and then the nozzle member 20 is moved up at a low speed by driving the air cylinder 25, and the servo motor 21 is driven in the rising direction (step S34).

On the other hand, when mounting the components, first, as shown in FIG. 7B, the nozzle member 2 is driven by driving the air cylinder 25.
The descent of 0 is performed at a low speed (step S36), whereby the nozzle member 20 descends to a position close to the target component, and then the servo motor 21 is driven so that the nozzle member 20 reaches the printed circuit board 3. It gently descends to the position (step S37). Then, the components are mounted (step S38), and then the air cylinder 25
The nozzle member 20 is moved up at a low speed by driving the servo motor 21 and the servo motor 21 is driven in the upward direction (step S39).

In the modes shown in FIGS. 11 and 12, when the component is sucked and mounted, the nozzle member 20 is moved up and down at a low speed, and the cushioning mechanism exerts an air cushion action, so that the target component is special. Even if the component is a shaped component or a component having a large weight, or a component that requires high precision mounting, the component is effectively prevented from falling off. In particular, in the mode shown in FIG. 12, when the component is sucked and mounted, the air cylinder 25 lowers the nozzle member 20 gently by driving the servo motor 21 until it reaches the component. When the member 20 abuts on the component or when the nozzle member is moved up and down in the component suction state, the component is effectively prevented from shifting and the mounting accuracy is improved.

As described above, according to the mounting machine, the air cushion action of the cushion mechanism provided in the air cylinder 25 causes the nozzle member 20 to move near the ascending end position and near the descending end position in the ascending / descending operation. The air cylinder 25
Even if the ascending / descending speed of the nozzle member 20 is set to be relatively high, the impact at the rising end position and the descending end position of the nozzle member 20 can be effectively mitigated to prevent the suction component from slipping or falling off. That is, in other words, it is possible to properly secure the mounting accuracy while setting the ascending / descending speed of the nozzle member 20 by the air cylinder 25 to a high level to shorten the cycle time. In particular, by changing and setting the nozzle raising / lowering operation according to the type of the target component as in the above embodiment, the cycle time can be shortened as much as possible within the range in which the component does not drop out.

Further, the above-mentioned cushion mechanism is integrally provided in the air cylinder 25, and the piston and the cylinder in the air cylinder 25 are made to have shape characteristics, and the piston 33 is provided with the seal members 39a and 39b. Since it is achieved by this, it is possible to exert the cushioning action with an extremely compact structure as compared with a structure in which a damper member or the like is separately provided. Therefore, when the cushion mechanism is provided, the head unit 5 is not unnecessarily increased in size or the weight is not significantly increased.

The mounting machine of the above embodiment is an example of the surface mounting machine according to the present invention, and its specific configuration can be appropriately changed without departing from the gist of the present invention. For example, in the above embodiment, the sub-ports 41a and 41 are provided in the upper and lower inner frame portions 40a and 40b of the air cylinder 25, respectively.
b is formed so that the air enclosed in the cushion chambers 42 and 43 is gradually discharged. However, instead of providing such sub-ports 41a and 41b, for example, in the inner frame portions 40a and 40b, for example, A fine groove extending in the axial direction may be formed, and the air enclosed in the cushion chambers 42 and 43 may be gradually discharged through the fine groove. Further, in addition to providing the sub-ports 41a and 41b, the narrow groove, and the like, notches are provided in the seal members 39a and 39b, so that the small diameter portions 38a and 38b and the inner frame portions 40a and 40b are formed.
The air enclosed in the cushion chambers 42 and 43 may be discharged through the space between

Further, in the above mounting machine, the component recognition camera 17 is arranged between the fixed unit conveyor 2a and the component supply section 4 on the side thereof, but it is not always necessary to arrange it in this way. . However, in an apparatus having a movable conveyor 2 such as the mounting machine, it is desirable to dispose the apparatus as in the above embodiment in order to improve mounting efficiency.

That is, when the printed circuit board 3 of the minimum size is conveyed, usually, in consideration of mounting efficiency, the component supply unit 4 close to the printed circuit board 3, that is, the unit conveyor 2 on the fixed side.
Since components are supplied from the component supply unit 4 on the side of a, by arranging the component recognition camera 17 between the fixed unit conveyor 2a and the component supply unit 4 on the side. The amount of movement of the head unit 5 for component recognition can be minimized, and thus mounting efficiency can be improved.

[0062]

As described above, according to the surface mounter of the present invention, when the piston reaches the vicinity of the moving end position, the small diameter portion of the piston is inserted into the thin cylindrical portion of the cylinder to form the small cylindrical portion and the small diameter portion. The sealing member seals the space between the piston and the inner part, and air is sealed between the small diameter part of the piston and the inner wall of the cylinder in this state, and the movement of the piston is decelerated by the cushioning action of the sealed air. The impact at the moving end position of the member, that is, the rising end position or the falling end position can be effectively mitigated.

Therefore, it is possible to preferably prevent the suction component from being displaced or dropped at the moving end position of the nozzle member, while shortening the cycle time by setting the up / down speed of the nozzle member by the air cylinder to be high. .

Moreover, since the piston and the cylinder of the air cylinder are provided with the shape characteristic and the sealing member is provided, the above-described operation and effect can be obtained.
There is no need to unnecessarily increase the size of the head unit or to significantly increase the weight during implementation.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of an entire surface mounter according to an embodiment of the present invention.

FIG. 2 is a front view showing a configuration of a head unit in the mounting machine.

FIG. 3 is a side view of the head unit.

FIG. 4 is a cross-sectional view of essential parts showing a nozzle member and a lifting / lowering drive mechanism thereof.

FIG. 5 is a bottom view of the head unit.

FIG. 6 is a partial cross-sectional view showing the structure of a nozzle member.

7 (a), (b) and (c) are sectional views showing the operation of the air cylinder when the nozzle member descends.

8A, 8B, and 8C are cross-sectional views showing the operation of the air cylinder when the nozzle member is raised.

FIG. 9 is a circuit diagram of an air supply system for an air cylinder.

10A and 10B are flowcharts showing control at the time of component suction and component mounting when a standard chip component is a processing target.

11A and 11B are flowcharts showing control at the time of component suction and component mounting when a specially shaped component or the like is a processing target.

12A and 12B are flow charts showing control at the time of component suction and component mounting in the case of processing a component that requires high-accuracy mounting.

[Explanation of symbols]

 5 Head Unit 20 Nozzle Member 20a Nozzle Shaft 20b Nozzle Holder 20c Nozzle 22 Housing 25 Air Cylinder 26 Nozzle Guide 27, 29 Spring 28 Bearing 33 Piston 33a Sleeve 34 Upper Pressure Chamber 35 Lower Pressure Chamber 36, 37 Ports 38a, 38b Small Diameter Portion 39a, 39b Seal member 40a, 40b Inner frame part 41a, 41b Sub port 42, 43 Cushion chamber

Claims (1)

[Claims] 1. A surface mounter comprising a nozzle unit for adsorbing an electronic component, and an air cylinder for driving the nozzle member up and down in a head unit that is movable across a component supply unit and a component mounting unit. The cylinder is composed of a piston connected to the nozzle member, and a cylinder having a pair of pressure chambers above and below the piston, each pressure chamber having an air supply / discharge port, and the pressure of at least one of the cylinders. A thin cylinder portion is formed in the chamber on the moving end side of the piston, and the air supply / discharge port is opened in the thin cylinder portion, while the piston has the thin cylinder portion of the cylinder at its axial end. And a small diameter portion that can be inserted into the thin cylinder portion of the cylinder or the small diameter portion of the piston seals between the thin cylinder portion and the small diameter portion when the small diameter portion is inserted into the thin cylinder portion. Shi Mounting means, and the sealing means is configured to achieve the sealing before the moving end position of the piston is reached.