JP2000252694A - Head structure of surface mounter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent malfunction of, and damage to, a nozzle assembling block by providing a head with a cover member which covers parts other than a nozzle placed in specified positions used to suck and mount parts. SOLUTION: A cover 70a and 70b is placed on a head. Accordingly, among movable parts, including a nozzle assembling block 30, in proximity thereto, only parts, such as a nozzle, 24, 25, 28,... moved due to the rotation of the nozzle assembling block 30, are externally opened and the other mechanical parts associated with the actuation of the nozzle assembling block 30 are not exposed at all. Therefore, even if positive pressure is applied to the nozzle 24, 25, 28,... and the like after interruption of negative pressure and, for example, any part jumps under the influence thereof, the part is effectively prevented from sticking to bevel gears 50a, 51, an anchoring hole 60 or the like. As a result, operation failure, such as a positioning member 61 becoming inoperable due to sticking of a part to the interior of the anchoring hole 60, and damage to the mechanical parts caused by such an event are prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mounter which mounts components on various substrates such as a printed circuit board by sucking components by nozzles of a component suction head provided in a head unit. The present invention relates to a head structure of a surface mounter having a rotatable nozzle assembly block having a plurality of nozzles.

[0002]

2. Description of the Related Art Heretofore, a head unit that can move between a component supply unit and a printed circuit board positioned at a predetermined working position is provided with a component suction head so as to be able to move up and down and rotate. 2. Description of the Related Art A surface mounter is generally known in which an electronic component is sucked by an attached nozzle, and a component is mounted by sucking a component from a component supply unit and then moving a head unit onto a printed circuit board.

In this type of surface mounter, the nozzle needs to be replaced depending on the type of component to be sucked.
In order to efficiently perform such nozzle replacement during mounting work, the present applicant mounts a nozzle assembly block in which a plurality of nozzles are radially arranged on a head and mounts the nozzle assembly block so as to be rotatable about a horizontal axis. A surface mounter has been proposed in which a nozzle can be selectively set at a predetermined use position in accordance with the type of component by rotating the nozzle assembly block (Japanese Patent Application No. 205585/1998).
issue). According to this surface mounter, the components can be mounted efficiently by rotating the nozzle assembly block while the head unit is moving and replacing the nozzles appropriately.

[0004]

By the way, in the above-mentioned surface mounting machine, a negative pressure is supplied to a nozzle at the time of picking up a component to suck the component, and at the time of mounting, the supply of the negative pressure is cut off to mount the component. Attachment is performed separately from the nozzle. At this time, after the negative pressure is cut off, a positive pressure is temporarily supplied to the nozzle to promote the separation of the components.

However, it is rare that the positive pressure acts on the parts more than necessary and the parts jump up. In this case, the jumped parts adhere to the mechanism for operating the nozzle assembling block, and the nozzle assembling block is moved. It is conceivable to cause malfunction or damage the mechanism. That is, in the above-described surface mounter having the nozzle assembly block in the head, a gear or the like for rotating the nozzle assembly block is disposed near the nozzle assembly block, and the parts that jump up adhere to the gear, It is possible that the nozzle assembling block is driven to rotate as it is, and the components bite into the gear, resulting in malfunction of the nozzle assembling block or damage to the gear.

Therefore, in a surface mounter in which a nozzle assembly block is mounted on a head, it is necessary to prevent such a malfunction of the nozzle assembly block and damage to a mechanism for operating the nozzle assembly block. There is.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problem. In a surface mounter rotatably provided with a nozzle assembling block in which a plurality of nozzles are radially arranged on a head, a nozzle assembling block is provided. The purpose is to prevent the occurrence and damage of malfunction.

[0008]

In order to solve the above-mentioned problems, according to the present invention, a head unit which is movable above a base in place of a component supply section and a component mounting section is provided. A head structure of a surface mounter having a unit rotatably supporting a nozzle assembling block having a plurality of nozzles for picking up components, which is arranged at a predetermined use position for sucking and mounting components. The head is provided with a cover member that covers a portion other than the nozzles. In this case, the cover member is provided so as to cover at least the mechanism part for operating the nozzle assembly block (claim 2).

According to such a head structure, a portion other than the nozzle arranged at a predetermined use position is prevented from being exposed to the outside, so that a component or a foreign matter to a mechanism portion for operating the nozzle assembly block is prevented. Intrusion can be effectively prevented.

A nozzle assembling block is disposed on the head so as to be rotatable about a horizontal axis, and each nozzle is radially provided around the nozzle assembling block. In a configuration in which a gear for transmitting torque is provided, a cover member is provided so as to cover at least this gear (claim 3). According to this configuration, it is possible to effectively prevent a component or foreign matter from being caught in the gear for transmitting the rotational force.

In a configuration in which the nozzle assembly block is provided with a plurality of positioning portions for positioning each nozzle at a use position as the above-described mechanical portion, a cover member is provided so as to cover at least the positioning portions. (Claim 4). According to this configuration, biting of components and foreign matter into the positioning portion is effectively prevented.

In many cases, a surface mounter arranges a component adsorbed by a nozzle on an imaging camera and images the component to recognize the component.
If the cover member is colored in a single color (claim 5), a background suitable for component recognition at the time of imaging can be formed by the cover member, thereby making it possible to increase the component recognition accuracy.

[0013]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 schematically shows an entire surface mounter (hereinafter abbreviated as a mounter) according to an embodiment of the present invention. In this figure, a conveyor 2 constituting a transport line is arranged on a base 1, and a printed circuit board 3 is transported on the conveyor 2 and stopped at a predetermined work position.

At the side of the conveyor 2, a component supply unit 4
Is arranged. The component supply unit 4 includes, for example, a plurality of rows of tape feeders 4a. Each of the tape feeders 4a stores and holds small pieces of electronic components such as ICs, transistors, and capacitors at predetermined intervals. The tape feed end is provided with a feed mechanism, and the tape is intermittently fed as components are picked up by a head unit 5 described later.

Above the base 1, a head unit 5 for mounting electronic components is provided. The head unit 5 can be moved between the component supply unit 4 and a predetermined work position of the printed circuit board 3. In the present embodiment, the head unit 5 is moved in the X-axis direction (the direction of the conveyor 2) and the Y-axis direction (the X-axis (In the direction perpendicular to).

That is, a pair of fixed rails 7 extending in the Y-axis direction and a ball screw shaft 8 driven to rotate by a Y-axis servomotor 9 are disposed on the base 1. A head unit support member 11 is disposed on the support member 11, and a nut portion 12 provided on the support member 11 is screwed to the ball screw shaft 8. A guide member 13 extending in the X-axis direction and a ball screw shaft 14 driven by an X-axis servomotor 15 are disposed on the support member 11 so that the head unit 5 can move on the guide member 13. The nut portion 16 (shown in FIG. 3) held in the head unit 5 is held by the ball screw shaft 14.
Is screwed into. The operation of the Y-axis servomotor 9 rotates the ball screw shaft 8 to move the support member 11 in the Y-axis direction, and the operation of the X-axis servomotor 15 rotates the ball screw shaft 14 to rotate the head unit 5. Move in the X-axis direction with respect to the support member 11.

The base 1 has a head unit 5
Component recognition cameras 17 and 18 are provided for recognizing the suction state of the electronic components sucked by the component recognition camera 17, and the head unit 5 moves above the component recognition cameras 17 and 18 after the components are sucked, whereby the component recognition cameras 17, 18 are moved. The pick-up component is imaged by 18.

FIGS. 2 to 4 show a specific structure of the head unit 5. In these figures, the head unit 5 is provided with two heads 20A and 20B having a plurality of nozzles for picking up components.

Each of the heads 20A and 20B is supported by the frame 5a of the head unit 5 so as to be able to move up and down in the vertical axis direction and to rotate around the vertical axis, and has a passage for introducing a negative pressure for picking up parts therein. It is provided at the lower end of the hollow nozzle shaft 21. Then, each head 20A, 20
A nozzle mounting block 30 is mounted on B, and a plurality of nozzles and the like are mounted on the nozzle mounting block 30. In the present embodiment, five nozzles 23 to 27
And one nozzle holder 28 to which the nozzle is detachably attached is fixedly assembled (see FIG. 6).

The nozzle assembly block 30 includes the head 2
0A, 20B rotatably supported around the horizontal axis,
Due to this rotational displacement, one of the nozzles 23 to 27 and the nozzle holder 28 (hereinafter, referred to as nozzles 23 to 28 if not particularly required to be distinguished) is selectively set to a predetermined use position. In addition, nozzles 23 to 28 are radially provided in the nozzle assembly block 30.

The head unit 5 further includes a Z-axis drive mechanism for raising and lowering the heads 20A and 20B, an R-axis drive mechanism for rotating the heads 20A and 20B around a vertical axis, and a negative pressure for component suction. A negative pressure supply system for supplying the pressure, a back pressure supply system for supplying a positive pressure for component mounting, and a nozzle assembly block 30 for each of the heads 20A and 20B.
A block drive mechanism or the like is provided to rotationally drive the motor.

The Z-axis driving mechanism includes a Z-axis servomotor 31 as a driving source fixed to the upper portion on both right and left sides of the frame 5a.
and a rack 33 supported to be able to move up and down with respect to a.
The rack 33 is connected to the upper end of the nozzle shaft 21 via a bracket 34, and a pinion 32 is mounted on an output shaft of the servomotor 31, and the pinion 32 is engaged with the rack 33. I have. That is, when the pinion 32 is rotated by the operation of the Z-axis servomotor 31, the rack 3
3, bracket 34, nozzle shaft 21 and head 2
0A (or 20B) moves up and down integrally with the frame 5a.

The R-axis drive mechanism includes an R-axis servo motor 36 as a drive source fixed to the center of the frame 5a, a gear 37 mounted on its output shaft, and the R-axis drive mechanism mounted on the nozzle shaft 21. A gear 38 meshes with the gear 37, and the nozzle shaft 21 and the head 20A (or 20B) are integrally rotated by the operation of the R-axis servo motor 36.
The nozzle shaft 21 and the gear 38 are connected by a spline so that the gear 38 can move up and down relative to the nozzle shaft 21 and the nozzle shaft 21 and the gear 38 rotate integrally.

Although the illustration of the negative pressure supply system is omitted,
A vacuum generator is provided for each of the heads 20A and 20B so that a negative pressure can be supplied to the passage in each of the nozzle shafts 21 via a valve or the like. Also, the positive pressure supply system is
A non-illustrated compressor is provided so that a positive pressure can be supplied to the passage in each of the nozzle shafts 21 via a valve or the like. A block drive mechanism for rotating each nozzle assembly block 30 will be described later.

FIGS. 5 to 9 show a specific structure of the head 20A. In these figures, an inverted U-shaped holder 40 for holding the nozzle assembling block 30 so as to be rotatable about a horizontal axis is connected to the lower end portion of the nozzle shaft 21. As shown in FIG. 8, the horizontal shaft 41 is rotatably mounted horizontally, and the nozzle assembly block 30 is fixed to the horizontal shaft 41.

The nozzle assembling block 30 has a plurality of nozzle assembling recesses 42 extending in a direction perpendicular to the horizontal axis 41 at regular intervals in the rotation direction. The nozzles 23 to 28 are radially mounted on the nozzle mounting block 30 by fitting and fixing the nozzles 28 to 28.

When the nozzle assembly block 30 is driven to rotate around the horizontal axis 41 by the block driving mechanism, one of the nozzles 23 to 28 or the nozzle holder is selectively moved to a predetermined use position. That is, it is arranged at the lower end of the heads 20A and 20B (the position of the nozzle 25 in FIGS. 5 to 9).

The block drive mechanism includes a servomotor 52 as a drive source mounted on the frame 5a and a transmission mechanism for transmitting the rotation to the nozzle assembly block 30.

More specifically, as shown in FIGS. 2 and 3, a block driving shaft 45 extending parallel to the nozzle shaft 21 and capable of ascending and descending and rotating around a vertical axis is provided on the frame 5a. A pulley 54 is mounted on the shaft 45 and the servo motor 5
Pulley 53 is mounted on the output shaft of
A belt 55 is mounted over the portions 3 and 54. Thus, the operation of the servo motor 52 causes the shaft 45 to move.
Are driven to rotate. The shaft 4
5 and the pulley 54, the shaft 45 with respect to the pulley 54
Relative to the shaft 45 and the pulley 5
4 are connected by a spline so as to rotate integrally.

The shaft 45 is a hollow pipe having a passage 45a for guiding air into the shaft 45. As shown in FIG. 2, an upper portion of the shaft 45 is inserted through a through hole formed in the bracket 34. A bridge member 4 whose lower part is attached to the upper end part of the holder 40 so as to be relatively rotatable.
6 is rotatably supported at one end via a bearing.

As shown in FIGS. 5 to 7, a gear 47 is mounted on the lower end of the shaft 45.
7 meshes with a gear 48 mounted on the upper end portion of the holder 40 so as to be relatively rotatable.
Transmission shaft 5 rotatably supported by holder 40
0 meshes with the gear 50a at the upper end. Further, a bevel gear 50b integrally provided at the lower end of the transmission shaft 50 meshes with a bevel gear 51 integrally assembled with the nozzle assembly block 30. The gear 48 has a pair of upper and lower gear portions 48a, 48b, and a gear 47 attached to the lower end of the shaft 45 with respect to the upper gear portion 48a is provided with respect to the lower gear portion 48b. The gears 50a at the upper end of the transmission shaft 50 mesh with each other.

As a result, when the servo motor 52 operates and the block driving shaft 45 rotates, the rotation about the vertical axis is transmitted through the gears 47 and 48, the gears 50a and 50b of the transmission shaft 50, and the bevel gear 51. The block drive mechanism is configured so that rotation is transmitted to the nozzle assembly block 30 while being converted into rotation about the horizontal axis.
Although not shown, the servo motor 52 has a built-in clutch, and is configured to automatically switch the output shaft to a freely rotatable state when the servo motor 52 is stopped.

The nozzle assembling block 30 has a passage 56 extending parallel to the horizontal axis 41 corresponding to each nozzle assembling recess 42. These passages 56 include nozzles 23 to 28 each having one end mounted in the nozzle assembling recess 42.
While the other end is connected to the nozzle assembly block 3
0 (the right end in FIG. 7). When the nozzles 23 to 28 are set at the predetermined use positions, the nozzles 23 to 28 set at this position are set.
Is connected to a passage 57 formed in the holder 40, and communicates with a passage in the nozzle shaft 21 through this passage 57, so that the components such as the nozzles 23 to 28 set at the use positions are sucked. Negative pressure is supplied. As shown in FIG. 7, the passage 56 corresponding to the nozzle holder 28 among the nozzles 23 to 28 passes through the through-hole 58 of the holder 40 in which the horizontal shaft 41 is disposed, and the negative pressure is applied to the nozzle holder 28. Is formed.

The nozzle assembling block 30 has an engaging hole 60 for positioning the nozzles 23-28.
(Positioning portion) is formed on the side of each nozzle assembling concave portion 42, and an air cylinder 62 provided with a tapered positioning member 61 that can be engaged with the engaging hole 60 is provided on the holder 40. I have.

The air cylinder 62 is disposed above the nozzle assembly block 30, that is, on the opposite side of the nozzles 23 to 28 from the use positions. A piston 63 is provided inside the air cylinder 62, and pressure chambers 64 a and 64 b are formed above and below the piston 63. The positioning member 61 is formed integrally with the lower end of the piston 63.

The upper pressure chamber 64a of the air cylinder 60 is
The shaft 4 for driving the block is passed through the holder 40 and the passages 65 and 66 formed inside the bridge member 46.
5 communicates with the passage 45a. On the other hand, the lower pressure chamber 6
4b is an air vent passage 6 formed in the holder 40.
7, a return spring 68 is disposed in the pressure chamber 64, thereby biasing the piston 63 to the upper end position.
That is, the passage 45a in the shaft 45 is connected to an air supply source via a hose (not shown) and an electromagnetic valve. When the valve is opened to supply air into the shaft 45, the return spring 68 The piston 63 is pushed down against the urging force of this, so that the positioning member 61 is engaged in the engagement hole 60, while the valve is closed and the supply of air into the shaft 45 is shut off. Then, the positioning member 61 is retracted into the cylinder by the urging force of the return spring 68, whereby the positioning member 61 is disengaged from the engagement hole 60.

The holder 40 is further provided with covers 70a and 70b (cover members) for covering the nozzle assembly block 30.

Each cover 70a, 70b is
It is formed in a U-shape (see FIG. 6) so as to integrally cover the front surface, the lower surface, and the back surface along the surface, and FIGS.
As shown in the figure, the nozzles are arranged on both sides of the moving portion of the nozzles 23 to 28 in accordance with the rotation of the nozzle assembly block 30. Thereby, only the moving parts of the nozzles 23 to 28 are opened to the outside, and the other parts, specifically, the bevel gears 50b and 51 of the block drive mechanism, the engagement holes 60 for positioning, and the like are assembled. A mechanism related to the operation of the block 30 is not exposed at all.

Each of the covers 70a and 70b is made of a metal plate or a resin plate, and its lower surface, that is, the surface corresponding to the component recognition cameras 17 and 18 is formed flat, and at least this lower surface is made of a monotone. It is colored in a single color, preferably black or white. Thereby, at the time of imaging of the components by the component recognition cameras 17 and 18,
The cover 70a, 70b is configured to form the background of the component.

While the structure of the head 20A on one side has been described above, the structure of the head 20B on the other side is similarly configured.

According to the mounting machine configured as described above, at the time of mounting, each head 20A moves while the head unit 5 moves between the component supply unit 4 and the printed board 3 set at a predetermined work position. , 20B nozzles 23-2
The component is picked up from the component supply unit 4 by the nozzle mounted on the nozzle holder 7 and the nozzle holder 28, and the component is mounted at a predetermined position on the printed circuit board 3. At this time, the nozzle is replaced by rotating the nozzle assembling block 30 while the head unit 5 is moving. That is, the nozzle to be set to the use position is changed by the rotation of the nozzle assembling block 30. As a result, the nozzle replacement can be performed efficiently, and the components can be mounted efficiently. In particular, if necessary, the nozzle assembly block 31 of each of the heads 20A and 20B is rotated while being driven.
A plurality of components are simultaneously sucked by the nozzles 3 to 27 and the nozzles mounted on the nozzle holder 28 and mounted on the printed circuit board 3, so that the components are mounted more efficiently.

In such a mounting operation,
As described above, the covers 70a, 7 are attached to the heads 20A, 20B.
0b, the nozzle assembly block 30 of the movable parts near the nozzle assembly block 30 including the nozzle assembly block 30 is mounted.
Only the moving parts of the nozzles 23 to 28 accompanying the rotation of the nozzle are opened to the outside, and other mechanical parts related to the operation of the nozzle assembling block 30, such as the bevel gears 50b and 51 and the engaging holes 60, are completely exposed to the outside. For example, even if the positive pressure is supplied to the nozzle after the negative pressure is shut off to promote the separation of the component from the nozzle, and the component jumps up due to the influence, for example, the bevel gear 50a,
Attachment of components to 51, engagement holes 60, and the like is effectively prevented. For this reason, a component is engaged between the bevel gear 50 b of the transmission shaft 50 and the bevel gear 51 of the nozzle assembly block 30, so that the nozzle assembly block 30 cannot be rotated or a component adheres to the engagement hole 60. It is possible to effectively prevent the occurrence of operation failures such as the positioning member 61 not being able to position the nozzle assembly block 30, and to prevent damage to the mechanism for operating the nozzle assembly block caused by such a situation. Can be.

Also, in the mounting machine, the background at the time of component imaging by the component recognition cameras 17 and 18 is formed using the covers 70a and 70b as described above. While preventing malfunction of the assembly block 30 and damage to the mechanism for operating the nozzle assembly block, there is also a feature that the accuracy of component recognition can be improved, thereby increasing the component mounting accuracy. .

In the structure of the above embodiment, only the moving parts of the nozzles 23 to 28 accompanying the rotation of the nozzle assembling block 30 among the movable parts near the nozzle assembling block 30 are opened to the outside. Covers 70a, 70
b, the cover 70a, 70b covers a part other than the nozzle arranged at a predetermined use position where components are sucked and mounted as widely as possible according to the specific configuration of the heads 20A, 20B. It may be configured so as to make it more difficult for components and foreign matter to enter the movable part near the nozzle assembling block 30 including the nozzle assembling block 30.

For example, as shown in FIGS. 10 and 11,
The support shaft 41 supporting the nozzle assembly block 30 is led out to the side of the holder 40, and the bevel gear 51 is attached to this lead-out portion, while the bevel gear 72, which is driven to rotate coaxially with the nozzle shaft 21, is attached to the holder 40. And the bevel gear 72 is attached to the bevel gear 51.
In the mounting machine in which the nozzles 23 'to 25' are changed by rotating the nozzle assembly block 30 by driving the bevel gear 72, the bevel gears 51 and 72 are arranged outside the holder 40 as described above. Therefore, as shown in the figure, the covers 70a and 70b may be provided so as to cover the bevel gears 51 and 72 and the like from below. In this case, the covers 70a and 70b may be formed integrally with the holder 40 in advance.

[0046]

As described above, according to the present invention, a movable head unit is provided above a base, and a plurality of nozzles for picking up parts are provided on the head unit. In the surface mounter having the head rotatably supporting the block, the head is provided with a cover member that covers a portion other than the nozzle disposed at a predetermined use position for sucking and mounting components, so that the nozzle assembly is performed. It is possible to effectively prevent the entry of components and foreign matter into the mechanism for operating the block. Therefore, it is possible to effectively prevent malfunction or damage of the device due to intrusion of components or foreign matter into the mechanism.

[Brief description of the drawings]

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

FIG. 2 is a front view (partially sectional view) showing a configuration of a head unit.

FIG. 3 is a sectional view taken along line AA of FIG. 2 showing a configuration of a head unit.

FIG. 4 is a plan view showing a configuration of a head unit.

FIG. 5 is a front view showing the structure of the head.

6 is a view on arrow B of FIG. 5 showing the structure of the head.

FIG. 7 is a sectional view taken along line DD of FIG. 6, showing the structure of the head.

FIG. 8 is a sectional view taken along the line CC of FIG. 5, showing the structure of the head.

FIG. 9 is a view on arrow E of FIG. 5 showing the structure of the head.

FIG. 10 is a side view showing another structure of the head.

11 is a view on arrow F of FIG. 10 showing the structure of the head.

[Explanation of symbols]

 5 Head Unit 19 Nozzle Exchange Station 20A, 20B Head 21 Nozzle Shaft 40 Holder 23-27 Nozzle 28 Nozzle Holder 30 Nozzle Assembly Block

Claims (5)

[Claims] 1. A head unit which is movable above a base in place of a component supply unit and a component mounting unit, and which is provided with a plurality of nozzles for component suction on the head unit. A head structure of a surface mounter having a head rotatably supporting a block, wherein a cover member for covering a portion other than a nozzle arranged at a predetermined use position for sucking and mounting components is provided on the head. The head structure of a surface mounting machine characterized by the following. 2. The surface mounter according to claim 1, wherein the cover member is provided so as to cover at least a mechanism portion for operating the nozzle assembly block. 3. The nozzle assembling block is disposed on the head so as to be rotatable around a horizontal axis, and the nozzle is provided radially around the nozzle assembling block. The head structure of a surface mounter according to claim 1, further comprising a transmission gear, wherein the cover member is provided so as to cover the gear. 4. The nozzle assembling block includes a plurality of positioning portions for positioning each nozzle at the use position as the mechanical portion, and the cover member is provided so as to cover the positioning portions. The head structure of a surface mounter according to claim 2, wherein the head structure is provided. 5. The head structure for a surface mounter according to claim 1, wherein said cover member is colored in a single color.