JPH11186798A - Printed board supporting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To elevate/lower a backup base through a simple structure while supporting a board horizontally. SOLUTION: Four shafts 6 supporting a backup base 4 provided with a ball screw groove and a spline groove penetrates a bearing part 12 provided rotatably with a nut 14 being screwed over the ball screw groove. A spline nut 16 to be engaged with the spline groove is also secured to the bearing part 12. When a servo motor 19 is turned, the nut 14 is turned through a timing belt 22 and a timing pulley 18 to elevate/lower the supporting shaft 6 thus elevating/lowering the backup base 4 while keeping horizontal state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board supporting apparatus which raises and lowers a backup base and supports a printed circuit board with backup pins provided on the backup base.

[0002]

2. Description of the Related Art As this kind of electronic component automatic mounting apparatus, one described in Japanese Patent Application Laid-Open No. 3-64989 is known. According to this conventional technique, a backup base or a substrate support table on which backup pins for supporting a printed circuit board are erected is guided by guide rods at four corners, and moves up and down by driving a cylinder or a ball screw.

[0003]

However, in the above prior art, the vertical movement is guided by the guide rod. However, depending on the position supported by the cylinder or the ball screw, the guide rod and its bearing are galled, and the backup base is broken. May not be kept horizontal and the substrate may not be supported horizontally. Further, if the rigidity of the backup base is not sufficient, the base may not rise horizontally due to bending even if a force for raising the gravity center position is applied. If the backup base is not horizontal, the printed circuit board supported by the backup base will not be horizontal, and there will be a problem that the descending distance of the suction nozzle that sucks the component when mounting the component varies.

In order to solve this problem, it is conceivable to provide a plurality of cylinders or ball screws. However, the number of parts of the structure increases and the structure becomes complicated.

SUMMARY OF THE INVENTION It is an object of the present invention to raise and lower a backup base while maintaining a state in which a substrate is horizontally supported by a simple structure.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a printed circuit board supporting device for raising and lowering a backup base with respect to a base and supporting the printed circuit board with backup pins provided on the backup base. A plurality of support shafts each having a ball screw groove and a spline groove formed thereon, and the support shaft is fixed to the base and penetrates the spline groove to guide the vertical movement thereof. A guide bearing, a nut rotatable on the base but immovable up and down and screwed into the ball screw groove formed on each support shaft, and a rotation for synchronously rotating each nut Means.

[0007] Since the support shaft supporting the backup plate also serves as a guide for raising and lowering and a driving source for raising and lowering, the overall structure can be simplified and the backup plate can be raised and lowered while maintaining the horizontal level.

Further, the present invention is preferably such that the support shaft is provided upright at the lower end face of the four corners of the backup base.

Preferably, the rotating means of the present invention comprises a driving motor, a driving pulley of the motor, and a belt stretched over a pulley fixed to the nut.

Since the nuts are rotated via the belt by the rotation of the drive motor, the nuts rotate in synchronization.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings.

As shown in FIGS. 1, 4 and 5, the printed circuit board 1 is conveyed to a conveyor (not shown) and placed on a chute 2 at a predetermined working position. The substrate 1 is transported by a transport belt 5 provided on a chute 2 and placed at a predetermined work position on the transport belt 5. A backup base 4 on which backup pins 3 for supporting the printed circuit board 1 are provided below the printed circuit board 1 placed on the chute 2 is positioned at a predetermined position in this manner. . On the upper surface of the backup base 4, the backup pins 3 are detachably provided upright.
The backup base 4 has a rectangular shape when viewed from above, and a support shaft 6 is erected in the vicinity of four corners on its lower surface so as to be unable to rotate downward. As shown in FIG. 6, a ball screw groove 8 and a spline groove 9 are engraved on the support shaft 6 so as to serve not only as a ball screw shaft but also as a ball spline shaft. The support shaft 6 includes a bearing 1 formed on a base 11 as shown in FIGS.
2 through. The height of the chute 2 is made constant with respect to the base 11.

The bearing 12 has a ball screw groove 8 of the support shaft 6.
2 is screwed through a ball (not shown) in FIG.
As shown in FIG.
5, but can be rotated through the bearing 12, that is, the base 11.
It is mounted so that it does not move up and down. A spline nut 16 is fixed to the lower part of the bearing portion 12 as a guide bearing for engaging the spline groove 9 via a spline ball (not shown) to restrict the rotation of the support shaft 6 but for guiding the vertical movement. I have. As a result, the rotation of the nut 14 causes the support shaft 6 to move up and down with respect to the base 11 by acting as a ball screw.

A timing pulley 18 is fixedly mounted on the nut 14. The pulleys 18 are fixed to the nuts 14 screwed to the four support shafts 6, respectively. As shown in FIG.
Are mounted on the bearing portion 12 such that their heights with respect to each other are the same. A servomotor 19 is further mounted on the base 11, and a drive pulley 20 provided on its output shaft is provided.
A timing belt 22 is stretched between the pulley 18 and the pulley 18.

Accordingly, the pulleys 18 rotate synchronously by the driving of the servomotor 19, the nuts 14 rotate by the same amount of rotation, the respective support shafts 6 move up and down the same distance, and the support shafts 6 Is moved up and down while keeping the level. This backup base 4
During the vertical movement, the four support shafts 6 each have a role as a drive source for vertical movement as a ball screw shaft, and also have a role of guiding the vertical movement without play as a spline shaft. still,
The timing belt 22 also extends around the idler pulley 23.

The backup base 4 is further provided with a clamp plate 25 standing upright.
The substrate 1 is sandwiched and fixed between the chute 2 and the protruding portion 26 of the chute 2 by the rise. The clamp plate 25 is attached to the base 4 so as to be vertically movable to the backup,
The compression spring 35 urges the ascending direction.

A mounting head 28 is movable above the clamped printed circuit board 1 as shown in FIG. 5, and an electronic component 30 sucked by a suction nozzle 29 attached to the head 28 is mounted on the board. 1.

At the center of the lower surface of the backup base 4, a detection plate 32 is erected, and the photo sensor 33 attached to the base 11 detects the detection plate 32 so that the backup base 4 reaches the origin position. I understand that
The drive of the servomotor 19 is stopped by a control device (not shown). In addition, a rising stopper 40 is formed on one of the support shafts 6.

The chute 2 on the right side in FIG. 4 is movable in accordance with the width of the substrate.
7 is attached. The moving body 39 moves along the rail 41 in the board width variable direction via the lever 37. A pair of rollers 38 sandwiching the lever 37 is attached to the moving body 39, and the clamp plate 25 is attached to the movable body 39. The lever 37 is guided by a roller 38 as the backup base 4 moves up and down, and changes the height position with respect to the base.

The operation will be described below.

First, the printed circuit board 1 is conveyed from the upstream device, and is moved to a predetermined work position on the chute 2 as shown in FIGS.
Stopped as shown.

Next, based on the thickness data of the substrate 1 stored in a storage device (not shown), a rotation amount to be rotated is instructed from a control device (not shown), and the servo motor 19 rotates. This rotation amount is a rotation amount corresponding to the rising distance at which the backup base 4 at the origin position rises and the backup pin 3 comes into contact with the back surface of the substrate 1 or the distance where a predetermined gap is formed in view of a margin.

Thus, the pulley 20 rotates and the four pulleys 18 rotate by the same amount of rotation synchronously via the timing belt 22. Accordingly, the rotation of the nut 14 causes the respective support shafts 6 to rise by the same distance. Even when a moment due to the tension of the belt is applied to the shaft 6 at the time of the rise, the spline nut 16 allows the support shaft 6 to serve as a spline shaft.
Is guided without rattling. In this manner, the backup base 4 is raised while keeping the horizontal, the clamp plate 25 contacts the lower surface of the substrate 1, and the backup base 4 is further raised, so that the substrate 1 is urged by the compression spring 35. It is pressed as shown in FIG. The rise of the backup base 4 stops at the distance described above.

Next, the mounting head 28 takes out the electronic component 30 from a supply device (not shown), moves it, stops at a desired position on the printed circuit board 1 and moves down, and mounts the electronic component 30. . At this time, the part 3
Although the substrate 1 is mounted by being pressed a little distance after contacting the substrate 1, the substrate 1 is supported by the backup pins 3 and does not warp downward.

The mounting head 28 reciprocates between the supply unit and the substrate 1 to complete the mounting of the component 30 on the printed circuit board 1.

Next, the backup base 4 is lowered by the rotation of the servo motor 19, and the sensor 33 detects it.
And stops at the origin position shown in FIG.

Although the present embodiment has been described with reference to an electronic component mounting apparatus for mounting an electronic component on a substrate, the present invention relates to a coating apparatus for applying an adhesive for temporarily fixing the electronic component to the substrate by discharging the adhesive from a coating nozzle. Even if there is, it can be adopted for the structure for supporting the substrate.

Further, in this embodiment, the timing belt is wound around the pulley 18 for rotating each support shaft 6 and is rotated synchronously. However, each nut 14 may be rotated via a gear, or each nut may be rotated. The motor 14 may be rotated by an individual motor, and control may be performed using a control device such as a CPU to synchronize the rotation of each motor.

In this embodiment, all four support shafts 6 are provided with the ball screw grooves 8 and the spline grooves 9. For example, only the two diagonal positions are provided with the ball screw grooves 8.
In addition, a structure in which the spline groove 9 is carved may be used to guide up and down driving and up and down movement, and the other two may carve only the spline groove 9 and provide only the up and down guide without providing the nut 14. .

[0030]

As described above, according to the present invention, the support shaft for supporting the backup plate also serves as a guide for ascending and descending and as a driving source for ascending and descending. Can be raised and lowered.

[Brief description of the drawings]

FIG. 1 shows a printed circuit board supporting apparatus to which the present invention is applied.
It is a BB arrow front view.

FIG. 2 is an enlarged sectional side view of a bearing unit.

FIG. 3 is a diagram of a printed circuit board supporting device to which the present invention is applied;
FIG. 4 is a plan view of the AA arrow.

FIG. 4 is a side view of a printed circuit board supporting device to which the present invention is applied.

FIG. 5 is a side view of a printed circuit board supporting device to which the present invention is applied.

FIG. 6 is a side view showing a support shaft.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed circuit board 3 Backup pin 4 Backup base 6 Support shaft 8 Ball screw groove 9 Spline groove 11 Base 12 Bearing part 14 Nut 16 Spline nut (guide bearing) 18 Timing pulley (rotating means) 19 Servo motor (rotating means) 20 Drive pulley (rotating means) 22 Timing belt (rotating means)

Claims (3)

[Claims] 1. A printed circuit board supporting device for raising and lowering a backup base with respect to a base and supporting a printed circuit board with backup pins provided on the backup base, wherein the backup bases are supported and ball screw grooves are respectively provided. A plurality of support shafts having a spline groove formed therein, a guide bearing fixed to the base and penetrating the support shaft to engage with the spline groove and guide the vertical movement thereof, and rotatable on the base. However, there is provided a nut which is provided so as not to be able to move up and down and is screwed with the ball screw groove formed on each support shaft, and turning means for turning the respective nuts synchronously. Printed circuit board support device. 2. The printed circuit board support device according to claim 1, wherein the support shaft is provided upright at lower end surfaces of four corners of a backup base. 3. The apparatus according to claim 1, wherein said rotating means comprises a driving motor, a driving pulley of said motor, and a belt stretched over a pulley fixed to said nut. A printed circuit board support device as described in the above.