JPH10145091A - Electronic component mounting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a rapid acceleration/deceleration to reduce the loss time and vibration/noise by providing a cam curve of a fixed cam for canceling the rotational speed of a main shaft to be transmitted to a transfer head to apparently stop this head when the head arrives at a specified operation stage. SOLUTION: In a standing time (about 25-30% of one cycle) before/after transfer heads 20, 34, 21, 35 arrive at stages S1, S2, S3, S4, the rotational speeds to be transmitted to the heads 20, 34, 21, 35 are cancelled to apparently stop these heads at respective stages S1-S4. To do this, the rotational speed to be transmitted to the head 20 is cancelled by the action of a corresponding part of the cam curve to a first region. Thus the head 20 staying at the mounting state S4 can be stopped and can mount components during this staying time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component mounting apparatus for mounting components on a work while circulating a plurality of transfer heads.

[0002]

2. Description of the Related Art Among electronic component mounting apparatuses, there is a rotary type in which a plurality of transfer heads are circulated to mount components on a workpiece one after another. In this type of electronic component mounting apparatus, a plurality of transfer heads are arranged concentrically around a main spindle, and operation stages such as a suction stage for sucking components from a component supply unit and a mounting stage for mounting components on a work, It is defined as a fixed point on a circular orbit around which the transfer head circulates.

[0003]

By the way, in the conventional electronic component mounting apparatus, when attention is paid to a circular motion in a horizontal plane, a configuration is adopted in which the transfer head moves completely synchronously with the rotation of the main shaft. Was.

Further, the role of the transfer head in each operation stage (for example, in the mounting stage, the transfer head descends vertically to mount components on the work, and then moves up to the original position while leaving the components on the work. Considering the operation), the transfer head must be stopped in a horizontal plane (that is, the main shaft also stopped) in each operation stage in order to prevent a displacement from occurring at least until this role is fulfilled.
On the other hand, in order for the transfer head to move to the next operation stage, the main shaft must be rotated by a certain angle.

For this reason, it is essential to rotate the main shaft intermittently. However, if the spindle is intermittently rotated, the spindle is rapidly decelerated before and after each operation stage and then rapidly accelerated, and the loss time due to this acceleration / deceleration operation is inevitable. For this reason, it has been difficult to further increase the operation speed and improve productivity as compared with the current situation.

[0006] In addition, the rapid acceleration and deceleration operations are performed repeatedly and frequently, so that vibrations and noises are increased, not only harming the installation environment but also transmitting the vibrations to the workpieces and the parts supply section, etc., and thus the time of mounting and It may cause displacement during suction,
There is also a problem that the mounting quality tends to deteriorate.

Accordingly, an object of the present invention is to provide an electronic component mounting apparatus capable of improving both productivity and mounting quality.

[0008]

According to the present invention, there is provided an electronic component mounting apparatus comprising: a main shaft continuously rotating around a vertical central axis by a driving unit; a support unit rotating integrally with the main shaft; Fixed cam, and a plurality of transfer heads arranged concentrically around the main shaft, and provided one-to-one with the transfer head, and circumferentially in contact with the fixed cam,
The driven part is rotatably supported by the support part, so that the rotation speed of the main shaft is transmitted to the transfer head according to the cam curve of the fixed cam, the component supply part supplies components to the transfer head, and the work is positioned. When the transfer head arrives at a certain operation stage, the fixed cam cancels the rotation speed transmitted from the main shaft to the transfer head and apparently stops the transfer head. Have.

[0009]

According to a first aspect of the present invention, there is provided an electronic component mounting apparatus, wherein a main shaft which is continuously rotated around a vertical central axis by a driving unit, a support which is integrally rotated with the main shaft, are fixed so as not to rotate. Fixed cam, a plurality of transfer heads arranged concentrically around the main shaft, and provided one-to-one with respect to the transfer head, and abuts on the fixed cam and is rotatable on the support portion. By being supported, there is provided a driven unit that transmits the rotation speed of the main shaft to the transfer head according to the cam curve of the fixed cam, a component supply unit that supplies components to the transfer head, and a positioning unit that positions the work, The fixed cam is used when the transfer head arrives at a certain operation stage.
It has a cam curve that cancels the rotation speed transmitted from the main shaft to the transfer head and apparently stops the transfer head.

[0010] Therefore, by rotating the spindle continuously rather than intermittently, rapid acceleration and deceleration of the spindle can be avoided, and loss time, vibration and noise due to rapid acceleration and deceleration are eliminated, and productivity and mounting are improved. Both quality can be improved.

Further, even if the main shaft rotates continuously, the rotational speed of the transfer head arriving at the operation stage becomes apparently zero due to the cam curve of the fixed cam. The mounting head can play a role in each operation stage.

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a side view of an electronic component mounting apparatus according to an embodiment of the present invention. In FIG. 1, 1
And 2, a positioning unit provided on the mounting stage S <b> 4 on the base 1.

4 is an X table, 5
Is a Y table provided on the X table 4, 6 is a Z table provided on the Y table 5, and 7 is a holder that holds the substrate 3 as a work and moves up and down by the Z table 6.

A component supply unit 8 is provided on the suction stage S2 at a position opposite to the mounting stage S4. Among the component supply units 8, 9 reciprocates a plurality of parts feeders 10 placed thereon in a direction perpendicular to the plane of FIG.
This is a moving table for setting a parts feeder 10 to which a component to be sucked is supplied to a suction stage S2.

Reference numeral 11 denotes a support frame supported above the base 1, and a fixed cam 12 is fixed to a lower portion of the support frame. In the center of the support frame 11, the center axis 0
A vertical main shaft 13 rotating around (FIG. 2) penetrates through a clearance t.

The rotational force of a main motor 14 serving as a driving unit is applied to the main shaft 13 by a pulley 15, a timing belt 16.
The main shaft 13 is not intermittently rotated but continuously rotated.

Reference numeral 18 denotes a horizontal rotary plate fixed coaxially to a lower portion of the main shaft 13, and the rotary plate 18 corresponds to a support portion and continuously rotates with the main shaft 13. An annular guide rail 19 is fixed to the lower surface of the rotating plate 18.

In this embodiment, around the main shaft 13,
In addition to the transfer heads 20 and 21 shown in FIG.
As shown in the figure, transfer heads 34 and 35 are provided every 90 degrees, and these transfer heads 20, 34, 21 and 35 are provided.
Is provided with suction nozzles 22 and 23 for sucking components at a lower portion thereof.

Between the main shaft 13 and each of the transfer heads 20, 34, 21, 35 described above, the rotational speed of the main shaft 13 is controlled by a cam curve constituted by the peripheral surface 12a of the fixed cam 12 (FIG. 2). According to the transfer heads 20, 34, 2
A driven portion 24 for transmitting the driving force to the driven members 1 and 35 is interposed.

In the driven portion 24, a link 25 is bent in a “<” shape, and the bent portion is rotatably supported by a shaft 26. In addition, a cam follower 2 that is in contact with the peripheral surface of the fixed cam 12 is provided at an end of the main shaft 13 side.
7 is attached, and a downward shaft 28 is fixed to an end opposite to the main shaft 13. Furthermore, this shaft 2
The lower end of 8 is rotatably connected to the upper part of the slider 29.

Further, a horizontal arm 30 is provided below the rotating plate 18, and transfer heads 20, 34, 21 and 35 are fixed to the outer end of the arm 30. A slider 31 slidably engaged with the guide rail 19 is fixed to an inner end of the arm 30, and the transfer heads 20, 34, 21, and 3 of the upper surface of the arm 30 are fixed.
A guide rail 32 is fixed at a position immediately inside the fifth rail 5. The slider 29 is slidably engaged with the guide rail 32 in the longitudinal direction of the arm 30.

Further, each driven portion 24 is provided with a spring 33 for applying an elastic force to the link 25, and the link 25 is urged by the elastic force of the spring 33 so that the cam follower 27 moves around the fixed cam 12. It follows the surface (cam curve).

The electronic component mounting apparatus of the present embodiment has the above-described configuration, and its operation will be described below.

First, an outline of the operation will be described with reference to FIG. As described above, in the electronic component mounting apparatus of the present embodiment, there are four transfer heads 20, 34, 21, and 35,
These basically circulate in the direction of arrow M.

Then, at the nozzle switching stage S1, switching to the suction nozzle to be used next is performed, and the suction stage S
In 2, the parts are sucked from the parts feeder 10.
Then, the position shift of the sucked component is detected at the recognition stage S3, the position shift is corrected at the mounting stage S4, the component is mounted on the substrate 3 on the positioning unit 2, and the process returns to the nozzle switching stage S1. Things.

Here, the main shaft 17 and the rotating plate 18 continuously rotate around the central axis 0 at a constant speed in the direction of arrow M. Further, since the shaft 26 of each driven portion 24 is fixed to the rotating plate 18, the shaft 26 at the bent portion of the link 25 is also
It continuously rotates at a constant speed on a circular orbit deviated from the central axis 0 by a certain distance.

On the other hand, the transfer heads 20, 34, 21, 35
The rotation speed of the transfer heads 20 and 3 is the same as the outer end of the arm 30, and the arm 30 is slidably engaged with the slider 31 and the guide rail 19.
4, 21 and 35 are not directly connected to the main shaft 13 for rotation about the central axis 0, and the rotating plate 18 (that is, the main shaft 13)
Is not directly reflected on the rotation speeds of the transfer heads 20, 34, 21, and 35.

That is, the transfer heads 20, 34, 21, 35
The rotation speed is determined by adjusting the cam curve of the fixed cam 12. Then, according to the relationship described below, as shown in FIG.
Stop time before and after the stages 1 and 35 arrive at the stages S1, S2, S3 and S4 (about 25 to 30% of one cycle)
, The rotational speed that can be transmitted to the transfer heads 20, 34, 21, and 35 is canceled, and the transfer heads 20, 34, 21, and 35 apparently move to the respective stages S1, S2, and S.
3. Stop at S4.

Of course, at other times, the transfer heads 20, 34, 21, and 35 have rotational speeds to advance to the next stage.

Now, the mounting stage S4 (other stages S
1 to S3 are the same as described below).
When, passes, a locus as shown in FIG. 3 is drawn.

First, the shaft 26 continuously rotates integrally with the rotary plate 18, so that the shaft 26 always performs a constant-speed circular motion.

With the center axis 0 and a straight line L passing through the mounting stage S4 interposed therebetween, the angle at which the axis 26 moves (trajectory N1) during the stop time is α, and the locus of the cam follower 27 during the stop time is N2. The area of the peripheral surface 12a where the cam follower 27 is in contact with the circumference is defined as a first area A. Further, the peripheral surface 12a with which the cam follower 27 is in contact after the stop time has elapsed.
Region is referred to as a second region B.

Here, during the stop time, the cam follower 27
Is in circumferential contact with the first area A, and at this time, the transfer head 20
Can be stopped by canceling the rotational speed that can be transmitted to the transfer head 20 by the action of the portion corresponding to the first area A in the cam curve.

More specifically, as shown in FIG. 3, the cam curve of the first area A may be shaped so as to be cut from the outside to the inside as viewed from the center axis 0. Even if a circular motion is made, the shaft 28 simply moves linearly on the straight line L as shown by a chain line, and the transfer head 2
The position of 0 does not change. Thus, the transfer head 20 can be stopped at the mounting stage S4 during the stop time, and during this stop time, the transfer head 20 can play the role of component mounting without any trouble.

On the other hand, in the second area B, the rotation speed of the transfer head 20 is accelerated from zero to a predetermined value, contrary to the first area A. That is, a curve that protrudes outward as viewed from the center axis 0 may be used, which is opposite to the first area A.

In the cam curve, the first area A and the second area A
Portions other than the region B may be connected smoothly using a smooth curve.

In this embodiment, as shown in FIG. 2, a four-lobe substantially cross-shaped cam curve is used.
Various changes are made according to the shape of No. 5, etc.

Here, as is apparent from the above description of the operation, according to the present embodiment, it is not necessary to rapidly accelerate or decelerate the main shaft 17, but only by smoothly and continuously rotating the main shaft 17, a sufficient stopping time at each stage, Transfer heads 20, 34, 21, 35
Can be stopped.

[0039]

The present invention is configured as described above.
By eliminating rapid acceleration and deceleration, loss time, vibration and noise can be reduced, and both productivity and mounting quality can be improved.

[Brief description of the drawings]

FIG. 1 is a side view of an electronic component mounting apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of an electronic component mounting apparatus according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram of an operation of the electronic component mounting apparatus according to the embodiment of the present invention;

[Explanation of symbols]

 2 Positioning unit 8 Component supply unit 12 Fixed cam 13 Main shaft 14 Main motor 18 Rotating plate 20, 21, 34, 35 Transfer head 24 Follower unit S Operation stage

Claims (2)

[Claims] 1. A main shaft that is continuously rotated around a vertical central axis by a drive unit, a support unit that rotates integrally with the main shaft, a fixed cam that is fixed so as not to rotate, and a concentric circle around the main shaft. A plurality of transfer heads arranged in a shape, and provided one-to-one with respect to the transfer head, and circumferentially in contact with the fixed cam, and rotatably supported by the support portion, thereby forming the main spindle. A driven unit that transmits a rotation speed according to a cam curve of the fixed cam to the transfer head, a component supply unit that supplies a component to the transfer head,
A positioning section for positioning a workpiece, wherein the fixed cam cancels a rotation speed transmitted from the main spindle to the transfer head when the transfer head arrives at a certain operation stage, and An electronic component mounting apparatus having a cam curve for apparently stopping a head. 2. The operation stage includes a suction stage in which the transfer head suctions components from the component supply unit, and a mounting stage in which the transfer head mounts components on a workpiece positioned by the positioning unit. The electronic component mounting apparatus according to claim 1, wherein the electronic component mounting apparatus is included.