JPH10107417A - Positioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positioning device, which is suitable for use with the peripheral positioning clamping mechanism of the circuit substrate of a cream solder printing machine, with which the point of stopping of a clamping position can be arbitrarily set based on the center of a circuit substrate. SOLUTION: A pair of clamping pawls 21 and 22, which abut on both ends of a circuit substrate 10 respectively, are opened and closed by a ball screw 20 which is inversely threaded with each other at the middle point as the boundary, a handle 24 is attached to one end of the ball screw 20, and the transmission mechanism of a drive actuator 37 is provided at the other end of the ball screw 20 through an electromagnetic clutch 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning device and, more particularly, to a positioning device for positioning a predetermined intermediate position between opposite ends of a work at a reference position.

[0002]

2. Description of the Related Art When an electronic circuit is manufactured, cream solder is applied on a circuit board made of an insulating material by a printing method, and a surface mount type component is mounted at a predetermined position on the circuit board. In such a state, the circuit board is gently guided into the reflow furnace. When heated to a temperature equal to or higher than the melting temperature of the solder in the furnace, the cream solder melts, whereby the electrodes of the mounted components and the connection lands formed on the circuit board are soldered, and A circuit will be formed.

Therefore, when manufacturing an electronic circuit, it is necessary to apply cream solder correctly on a circuit board. If the position is incorrect, correct soldering cannot be performed. In particular, in an electronic circuit designed to perform high-density mounting, it is necessary to apply cream solder more accurately.
Therefore, it is necessary to accurately position the circuit board and apply the cream solder.

[0004] When applying cream solder by printing, it is necessary at the time of printing of a high-density circuit board to finely set the printing pressure and pressing amount of the squeegee with the circuit board centered on the squeegee. When performing printing with the circuit board centered on the squeegee, a printing method in which the squeegee is moved in the same direction as the circuit board conveyance direction, and a width perpendicular to the circuit board conveyance direction and the width of the circuit board Of squeegee moving in two directions
There are different types of printing methods.

[0005]

A method in which cream solder is applied onto a circuit board by a printing technique while moving a squeegee in the same direction as the circuit board transport direction is a method in which the unit itself on which the circuit board is positioned is used. Since it is necessary to move the squeegee by a change in the width of the circuit board, the mechanism becomes large and the space becomes large. Further, in the method of fixing the circuit board, since the transport direction and the moving direction of the squeegee are the same, it is often not possible to sufficiently fix the circuit board in the transport direction, and pushing the squeegee leads to print misalignment.

On the other hand, in a system in which the squeegee is moved in the width direction of the circuit board and in the direction perpendicular to the carrying direction, the positioning and fixing of the circuit board are performed with sufficient accuracy and the circuit board has a desired shape. If it is rigid, stable printing position accuracy can be maintained without being affected by the squeegee pushing amount. However, in order to align the board with the center of the squeegee, a jig corresponding to the length of the circuit board was required.

The present invention has been made in view of such a problem, and it is possible to perform positioning of a predetermined intermediate position of a work without using a jig in response to a change in the length of the work. It is an object to provide a possible positioning device.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a positioning device for positioning a predetermined intermediate position between opposite ends of a work at a reference position, wherein the positioning device contacts the opposite ends of the work. A pair of clamp claws, a feed screw having opposite threads on both sides of the intermediate position so as to move in a direction in which the pair of clamp claws approach each other and in a direction away from each other; and A handle for rotating the feed screw, a drive means for rotating the feed screw forward and backward by a predetermined rotation angle, and a drive means interposed between the drive means and the feed screw. And a clutch for transmitting the driving force and, when cut off, the transmission of the driving force from the driving means to the feed screw is cut off. It is.

The screws on both sides of the intermediate position of the feed screw may be reverse screws having the same pitch, and the center between the opposite ends of the work may be positioned at the reference position.

When the driving means has a full stroke in the forward or backward direction, the clutch is disengaged, and the handle is rotated to contact the pair of clamp claws with the opposite ends of the work. The clutch may be connected by setting this position as an origin position when the pair of clamp claws are closed.

The drive means comprises a hydraulic cylinder having a predetermined stroke, a rack moved by the hydraulic cylinder, and a pinion meshing with the rack, and rotation is taken out from an output shaft to which the pinion is fixed. May be done.

[0012]

1 and 2 show an applicator for cream solder printing provided with a positioning device according to an embodiment of the present invention. The circuit board 10 is transported by a pair of conveyors 11 on both sides, and is moved below the cream solder printing position. In such a state, the frame 1 is moved by a lifting mechanism (not shown) as shown in FIG.
The circuit board 10 is raised so as to come into contact with the lower surface of the screen 13 supported by the squeegee 2. In such a state, the squeegee 14 moves on the screen 13 and corresponds to the opening formed in the screen 13 in advance. In some portions, cream solder is printed on the circuit board 10.

The positioning of the circuit board 10 in the transport direction is shown in FIG.
As shown in FIG. 2, the clamping is performed by a pair of clamp claws 21 and 22 located on the front side and the rear side in the transport direction of the circuit board 10, respectively. Clamp claws 21, 22
Are both moved between a predetermined stroke solid line position and a chain line position, and a pair of clamp claws 21,
22 is waiting at the dashed line position. If the circuit board 10 is conveyed to a position below the printing position by the conveyor 11 in such a state, the lifting / lowering operation is performed by a lifting / lowering means (not shown), and the clamp claws 21 and 22 are moved.
Moves from the dashed line position to the solid line position, thereby positioning the circuit board 10 with the intermediate position in the transport direction as the reference position.

Next, the positioning device will be described. As shown in FIGS.
Ball screw 20 arranged to extend in the carrying direction of
Therefore, this is achieved. The ball screw 20 has a small-diameter portion 25 at an intermediate position in the longitudinal direction, and the front end and the rear end of the small-diameter portion 25 are reverse-threaded. The female screw holes of the movers 23 and 24 are screwed to the ball screw 20 on both sides of the small diameter portion 25. The clamp claws 21 and 22 are attached to the moving elements 23 and 24, respectively.

The ball screw 20 has a front end and a rear end rotatably supported by bearings 27 and 28, respectively. A handle 29 is attached to an end of the ball screw 20 on the bearing 27 side. On the other hand, an electromagnetic clutch 30 is attached to the end of the ball screw 20 on the bearing 28 side. The electromagnetic clutch 30 includes a drive wheel 31 and a driven wheel 32.

A pulley 35 is attached to the drive wheel 31 of the clutch 30.
Is installed. The pulley 35 is connected to an output shaft 38 of a driving actuator 37 via a timing belt 36.
And a pulley 39 attached to the pulley 39.

Next, the drive actuator 37 will be described. The actuator 37 has an air cylinder 43 as shown in FIG. A rack 45 is fixed to a piston rod 44 of the air cylinder 43. The rack 45 meshes with the pinion 46. The pinion 46 is fixed to the output shaft 38, and the output rotation is extracted through the output shaft 38.

As shown in FIG. 5, the positioning device is supported on a substrate raising base 50. Then, the circuit board 10 is mounted on the board raising base 50.
Backup block 51 for supporting (see Fig. 4)
And a backup pin 52 (see FIG. 6).

Next, the operation of positioning by the positioning device having the above configuration will be described. When performing this positioning operation, first, the piston rod 43 is made to protrude until the air cylinder 43 reaches a full stroke in the forward movement direction. This state corresponds to a state in which the pair of clamp claws 21 and 22 are closed as shown in FIG. In such a state, the electromagnetic clutch 30 is disengaged, and the driving wheel 31 and the driven wheel 32 are set in a non-transmission state.

In such a state, the ball screw 2
0 is a handle 29 attached to the opposite end because it is disconnected from the drive actuator 37.
Thus, the ball screw 20 can be freely rotated. Accordingly, in such a state, the circuit board on which the cream solder is applied is disposed between the pair of clamp claws 21 and 22, and in such a state, the handle 29 is gently rotated, and the clamp claws 21 and 22 are rotated by the ball screw 20. Are moved in the directions approaching the ends of the circuit board 10, that is, from the position shown by the chain line to the position shown by the solid line in FIG. Then, these clamp claws 21 and 22 both come into contact with both ends of the circuit board 10 and a pair of clamp claws 2 are formed.
If the circuit board 10 is clamped by 1 and 22, the rotation operation of the handle 29 is stopped in this state. By switching the electromagnetic clutch 30 to the connected state in such a state, positioning is performed.

When the clutch 30 is switched to the connected state, the air cylinder 43 of the driving actuator 37 repeats the forward movement and the backward movement, so that the pair of clamp claws 21 and 22 shown in FIG. Reciprocate between positions. In the position of the solid line, the circuit board 10
Is correctly positioned with reference to the intermediate position in the transport direction.

When the circuit board 10 is conveyed by the conveyor 11 and moved below the printing position, the air cylinder 43 moves forward, whereby the clamp claws 21 and 22 move from the chain line position to the solid line position, respectively. The circuit board 10 is positioned with reference to an intermediate position in the longitudinal direction thereof, and is raised by the board raising base 50 and supported by the frame 12 shown in FIGS. 1 and 2.
Is raised to the lower side. In this state, the squeegee 14 moves on the screen 13, and the cream solder is applied to the upper surface of the circuit board 10.

As described above, the positioning device according to the present embodiment is provided with the ball screws 20 that are reversely screwed to each other with the middle small-diameter portion 25 as a boundary. Thus, a transmission mechanism with the driving actuator 37 is provided. A pair of movers 23 and 24 each having a ball nut screwed into the ball screw 20 is connected to the ball screw 20 as shown in FIG.
As shown in (1), the opening and closing movement of a fixed stroke is performed.

The circuit board 10 conveyed by the conveyer 11 is received by the backup pins 52 and the backup block 51 when the board raising base 50 is raised, whereby the circuit board 10 is detached from the conveyer 11. Next, by rotating the ball screw 20 by a predetermined stroke in the closing direction by the driving actuator 37, the circuit board 10 is positioned with reference to the intermediate position in the transport direction.

To adjust the positioning in accordance with the change in the length of the circuit board 10, the clutch 30 is disengaged, the positioning handle 29 is rotated, and the pair of right and left clamp claws 21 and 22 are adjusted.
Are brought into contact with both ends of the circuit board 10 in the transport direction so that the electromagnetic clutch 30 is connected again in this state to perform the adjustment operation.

The dimensions of the circuit board differ from lot to lot. Therefore, each time the lot is changed, the electromagnetic clutch 30 is disconnected, and the handle 29 is rotated to rotate the ball screw 20 manually. Since the directions of the screw of the ball screw 20 are opposite to each other with the small diameter portion 25 as a boundary as described above, the clamp claws 21 and 22 on both sides move in opposite directions. Therefore, the ball screw 2 is gently moved by the handle 29.
0, and the electromagnetic clutch 30 is connected with the clamp claws 21 and 22 correctly abutting on both ends of the circuit board 10 as shown in FIG. Then, the actuator 37 opens and closes the pair of clamp claws 21 and 22 so that the contacted position becomes the reference position on the forward movement direction side of the driving actuator 37.

The positioning device for the circuit board 10 in such a cream solder printing machine performs printing with the direction of conveyance of the circuit board 10 and the direction of printing by the squeegee 14 perpendicular to each other. By using such an apparatus, it is possible to arbitrarily position the circuit board 10 at the center position of the circuit board 10 in the transport direction of the circuit board 10 irrespective of a change in the length of the circuit board 10.

In response to a change in the length of the circuit board 10,
As described above, it is only necessary to operate the handle 29 while disconnecting the electromagnetic clutch 30 to perform the positioning, and the positioning of the center of the circuit board 10 can be performed without using a jig. Setup time can be reduced.

Further, in such a positioning device,
The printing direction of the cream solder on the circuit board 10 and the fixing of the circuit board 10 are used together, and the circuit board 10 is fixed from all sides, so that the positioning of the circuit board 10 at the time of printing is sufficiently accurate and the required rigidity is maintained. Since the printing can be performed in a state, the printing accuracy of cream solder is expected to be improved.

In the above embodiment, the screws on both sides of the small diameter portion 25 of the ball screw 20 are made to be reverse screws and their pitches are made equal to each other.
The positioning is performed with the center in the length direction of the circuit board 10 as a reference position. However, by changing the pitch of the screws on both sides of the small diameter portion 25, the reference position is shifted to one side with respect to the center. It becomes possible to bias.

[0031]

According to the present invention, a pair of clamp claws abutting between opposite ends of a work and an intermediate position such that the pair of clamp claws move in a direction approaching each other and in a direction away from each other. A feed screw having opposite screws on both sides of the feed screw, a handle for manually rotating the feed screw, a drive means for rotating the feed screw at a predetermined rotation angle forward and reverse, and a drive means and a feed screw Intervened,
And a clutch that, when connected, transmits a driving force from the driving means to the feed screw and, when disconnected, cuts off transmission of the driving force from the driving means to the feed screw. .

Therefore, by disengaging the clutch and manually rotating the feed screw with the handle, the distance between the pair of clamp claws can be arbitrarily adjusted, thereby making it possible to adjust to the size of the work.
And when the clutch is connected in such a state,
The clamp pawl opens and closes with the set position as the origin in accordance with the normal rotation and the reverse rotation of the driving means at the predetermined rotation angle.

According to the configuration in which the screws on both sides of the intermediate position of the feed screw are reverse screws having the same pitch and the center between the opposite ends of the work is positioned at the reference position, a pair of works is provided. Positioning is performed about the center between the ends abutted by the clamp claws.

When the driving means has a full stroke in the forward or backward direction, the clutch is disengaged, and the handle is rotated to bring a pair of clamp claws into contact with opposite ends of the work. According to the configuration in which the clutch is connected with this position as the origin position when the pair of clamp claws are closed, by connecting the clutch, the driving unit opens and closes based on the origin position when the clamp claw is closed. The operation is performed.

A hydraulic cylinder having a predetermined stroke and a rack moved by the hydraulic cylinder;
According to the configuration in which the rack and the pinion that meshes with each other, and the rotation is taken out from the output shaft to which the pinion is fixed, it is possible to generate a predetermined stroke by the stroke of the hydraulic cylinder, The clamp claws perform opening and closing operations in accordance with the stroke of such a hydraulic cylinder.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part showing a cream solder application device.

FIG. 2 is a vertical sectional view showing a main part of a cream solder application device.

FIG. 3 is a main part plan view showing a cream solder application device;

FIG. 4 is a plan view of the positioning device.

FIG. 5 is a front view of the positioning device.

FIG. 6 is a side view of the positioning device.

FIG. 7 is an exploded perspective view of a driving actuator.

[Explanation of symbols]

10 ‥‥ circuit board, 11 ‥‥ conveyor, 12 ‥‥ frame,
13 ‥‥ screen, 14 ‥‥ squeegee, 15 ‥‥ cream solder, 20 ‥‥ ball screw, 21, 22 ‥‥ clamp claw, 23, 24 ‥‥ mover (ball nut), 25 ‥
{Small diameter part, 27, 28} Bearing, 29} Handle, 3
0 electromagnetic clutch, 31 drive wheel, 32 forward wheel, 35 pulley, 36 timing belt, 37
{Drive actuator, 38} Output shaft, 39}
Pulley, 43 ‥‥ air cylinder, 44 ‥‥ piston rod, 45 ‥‥ rack, 46 ‥‥ pinion, 50 ‥‥ board rising base, 51 ‥‥ backup block, 52 ‥‥
Backup pin

Claims (4)

[Claims] 1. A positioning device for positioning a predetermined intermediate position between opposite ends of a work at a reference position as a reference position, comprising: a pair of clamp claws abutting on opposite ends of the work; A feed screw which is reversely screwed on both sides of the intermediate position so that the clamp claws of the feed screw move in a direction approaching each other and in a direction separating from each other; a handle for manually rotating the feed screw; and A drive unit for rotating the screw forward and backward by a predetermined rotation angle, interposed between the drive unit and the feed screw, and when connected, a driving force is transmitted from the drive unit to the feed screw and cut off And a clutch for cutting off the transmission of the driving force from the driving means to the feed screw when performed. 2. The method according to claim 1, wherein the screws on both sides of the intermediate position of the feed screw are reverse screws having the same pitch, and the center between the opposite ends of the work is positioned at a reference position. Positioning device. 3. When the driving means has a full stroke in the forward or backward direction, the clutch is disengaged, the handle is rotated, and the pair of clamp claws are moved to opposite ends of the work. 2. The positioning device according to claim 1, wherein the clutch is connected as an origin position when the pair of clamp claws are closed. 3. 4. The rotating means comprises a hydraulic cylinder having a predetermined stroke, a rack which is moved by the hydraulic cylinder, and a pinion which meshes with the rack, and which rotates from an output shaft to which the pinion is fixed. 2. The positioning device according to claim 1, wherein the device is taken out.