JPH11197588A - Lifting stroke control method for dispenser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of a cobwebbing defect at the time of coating application of an adhesive with a dispenser which lifts a syringe having a nozzle by rotation of a motor via a change mechanism by making the motor rotatable forward and backward and adjusting the forward and backward rotating range according to the distance in the vertical moving direction of an object to be coated and the nozzle. SOLUTION: This dispenser 10 lifts the syringe 14 having the nozzle 12 via the servo motor 16 and the change mechanism 18. To apply the adhesive on the object 22 to be coated by the dispenser 10, an operator first inputs a production start command and simultaneously inputs the stroke of the nozzle 12 to a CPU 20A. Next, the height and location of already mounted parts are read from a memory section 20C. Whether the nozzle 12 interferes with the already mounted parts or not is judged in the CPU 20a and if the nozzle interferes therewith, the servo motor 16 is driven to rise the dispenser 10. In succession, the syringe 14 is moved in a transverse direction and when the syringe arrives at the position where the syringe does not interfere with the already mounted parts, the nozzle 12 is lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a stroke of a dispenser for applying an adhesive to a member to be applied.

[0002]

2. Description of the Related Art For example, as a part of a surface mounting system for an electric circuit board, a dispenser for automatically applying an adhesive for temporarily fixing a chip component or the like to a predetermined application point on a printed circuit board is provided. There is an adhesive application device.

In such a dispenser, a syringe having an adhesive application nozzle at the lower end is brought close to an object to be applied, a predetermined amount of adhesive is discharged from the application nozzle, and then rises and moves to the next application point. Is controlled to be.

As an example of a mechanism for raising and lowering the syringe, for example, as disclosed in Japanese Patent Laid-Open No. 8-125320, the movement of a cam follower that moves up and down following an end face cam is transmitted to the syringe, and There is something that raises and lowers.

In this case, the vertical stroke of the syringe is
It is uniquely determined by the lift of the end face cam.

FIG. 6 shows a process of applying an adhesive by the dispenser.

[0007] In the state of FIG.
The adhesive 3 is applied to a predetermined position on the surface of the substrate and is moving toward the next application point 4.

Next, as shown in FIG. 6B, the nozzle 1 moves in the horizontal direction toward the next application point 4 and descends, and the adhesive 3A is applied onto the next application point 4. Discharge.

Next, as shown in FIG. 6 (C), the nozzle 1 rises, and at this time, stringing portions are formed from the upper end of the adhesive 3A and the tip of the nozzle 1, and these are respectively caused by surface tension. And the surface becomes a smooth surface as shown in FIG. 6 (D).

However, if the distance between the nozzle 1 and the substrate 2 is too short, the result is as shown in FIG.

FIGS. 7A and 7B are diagrams of FIG.
7B, but when the maximum separation distance between the nozzle 1 and the substrate 2 is too small, as shown in FIG. 7C, the adhesive 3A on the next application point 4 and the adhesive at the tip of the nozzle 1 With the strings connected in a stringing state, as shown in FIG.
The nozzle 1 may move laterally further to the next application point.

At this time, as shown in FIG. 7 (D), the stringing portion of the adhesive 3A hangs down on the side surface of the adhesive 3A, causing a so-called threading defect 3B.

However, as described above, since the lift stroke of the dispenser is uniquely determined by, for example, the lift of the rotary cam, the distance between the nozzle and the substrate depends on the thickness of the substrate, the properties of the adhesive, and the like. There is a problem that the distance cannot be optimally controlled.

Further, if the distance between the nozzle and the substrate is made too large in order to prevent stringing defects, a new problem arises in that the production efficiency is reduced.

Further, when the syringe is sequentially moved to the application point on the substrate and the adhesive is applied, the height of the mounted component adhered on the substrate by the already applied adhesive determines the elevation stroke of the syringe. If it exceeds, it is necessary to prevent interference between the nozzle and the already mounted components.

In this case, there is a problem that the nozzle must be detoured in the horizontal direction, a time loss occurs, and the production efficiency is reduced.

The present invention has been made in view of the above-mentioned conventional problems, and does not reduce production efficiency.
It is an object of the present invention to provide a method for controlling a dispenser up-and-down stroke, which can reliably prevent the occurrence of a poor threading at the time of applying an adhesive.

It is another object of the present invention to provide a method for controlling a stroke of a dispenser that can avoid interference between a nozzle and an already mounted component without reducing production efficiency.

[0019]

SUMMARY OF THE INVENTION The present invention relates to a method for controlling a stroke of a dispenser for raising and lowering a syringe having a nozzle for applying adhesive at a lower end thereof through a conversion mechanism for converting rotation of a motor into vertical movement. Said motor,
The above object is achieved by allowing the syringe to freely rotate forward and backward in accordance with the vertical movement direction of the syringe, and adjusting the forward and reverse rotation range according to the vertical movement distance between the application target and the nozzle. Things.

A step of reading information on the height and position of the mounted component adhered to the object to be coated with the coating adhesive; and a process of reading the height information and position information when the cylinder passes the position of the mounted component. Comparing the height of the nozzle with the mounted component to determine whether or not the nozzle interferes with the mounted component; And driving the motor until it is further raised.

According to the present invention, the motor for raising and lowering the syringe of the dispenser can be freely rotated forward and backward and its forward and reverse rotation range can be adjusted. Interference with already mounted components can be reliably prevented without lowering production efficiency.

[0022]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows an apparatus and a dispenser for carrying out a method for controlling a dispenser up / down stroke according to the present invention.

The dispenser 10 is provided with a syringe 14 having a nozzle 12 for applying an adhesive at a lower end thereof.
The servomotor 16 is vertically rotatable by a control device 20 in accordance with the vertical direction of the syringe 14 by means of a conversion mechanism 18 for converting the rotation of the syringe 6 into a vertical movement. At the same time, the forward / reverse rotation range is adjusted according to the vertical distance between the application target 22 and the nozzle 12.

The syringe 14 is held in a cylindrical syringe holder 24 so as to cover the outside thereof. The syringe holder 24 is vertically slid on a Z-axis holding member 26 on the apparatus body (not shown). It is freely supported.

1 is an air tube for introducing compressed air into the syringe 14, 30 is an air connector for connecting the air tube 28 to the syringe 14, and 32 is an air connector. Fixing members for fixing the upper end of the syringe 14 to the upper end of the syringe holder 24 are shown.

A horizontal circumferential groove 34 is formed on the outer periphery of the syringe holder 24, and a driving cam follower 36 provided at the tip of the conversion mechanism 18 is fitted to be rotatable in the circumferential direction. I have.

The conversion mechanism 18 includes an eccentric rotating cam 38.
And a cam follower 4 that can freely contact the eccentric rotary cam 38.
0 and a substantially L-shape, and one end of the cam follower 4
0, the other end rotatably supports the driving cam follower 36, and an apparatus body (not shown) at an L-shaped corner.
And a cam link 42 swingably supported via a swing shaft 42A on the side.

A driven timing pulley 38A is mounted on the eccentric rotary cam 38, and a drive timing pulley 16A is provided on the output shaft of the servo motor 16, and a timing belt 44 is wound around these. Thus, the eccentric rotary cam 38 is driven to rotate by the servo motor 16.

The reference numeral 46 in FIG.
And a spring for urging the cam follower 40 at one end thereof to constantly press against the eccentric rotary cam 38.

As shown in FIG. 1, the control unit 20 includes a central processing unit 20A and a manipulator for inputting a vertical stroke (Z-axis stroke) of the syringe 14 from the operator to the central processing unit 20A. -It has a machine interface 20B and a memory unit in which information on components already mounted on the application target 22 (for example, a substrate) is input.

The central processing unit 20A reads the Z-axis stroke information in the next production from the man-machine interface 20B, and the height and the location (XY coordinates) of the already mounted parts which have been input in the memory unit 20C in advance. Then, the optimum distance in the height direction between the nozzle 12 and the application target 22 at the time of applying the adhesive is calculated, the rotation angle of the servo motor 16 is controlled, and when the nozzle 12 moves to the next application point, In order not to interfere with the mounted components,
The servo motor 16 is driven to raise the dispenser 10.

Next, a process of applying an adhesive on the application object 22 by the dispenser 10 will be described with reference to FIG.

First, the man-machine interface 20
B, a production start command is input, and at this time,
A stroke (Z-axis stroke) of the nozzle 12 for realizing the maximum speed of the apparatus is input to the central processing unit 20A (see step 101).

Next, at step 102, the memory unit 2
The height and location of the already mounted component are read from 0C.

Next, the process proceeds to step 103, where the central processing unit 20A determines whether or not the nozzle 12 interferes with the already mounted component.
The servo motor 16 is driven to raise the entire dispenser 10 to a height that does not interfere.

Next, in step 105, when the syringe 14 is moved in the horizontal direction to reach a position (XY direction) where it does not interfere with the mounted components, the nozzle 12 is lowered to a predetermined position (see step 106).

If the nozzle 12 does not interfere with the already mounted components, the process directly proceeds to step 105, passes through step 106, and proceeds to step 107 where the adhesive is applied to the object 2.
2 (see FIG. 3).

Next, at step 108, the syringe 1
4 returns to the steady position, that is, the height position of the predetermined Z-axis stroke input in step 101, and prepares for the next movement and coating.

The maximum head of the eccentric rotary cam 38 is set to be large in consideration of a case where the installed component and the nozzle 12 interfere with each other, and usually, the angle range is smaller than the maximum head of the eccentric rotary cam 38. Causes the eccentric rotary cam 38 to rotate forward and reverse.

In the above embodiment, the conversion mechanism 18 converts the rotation of the eccentric rotary cam 38 into the elevation of the syringe 14. However, the present invention is not limited to this. What is necessary is just to move the syringe 14 up and down.

Accordingly, as shown in FIG. 4, for example, a conversion mechanism may be constituted by a vertical rack 48 integral with the syringe 14 and a pinion 50 for moving the rack 48 up and down.

As shown in FIG. 5, a conversion mechanism may be constituted by a vertically arranged ball screw 52 driven by the servomotor 16 and a female screw 54 meshing with the ball screw 52. . The internal thread 54 is integrally attached to the syringe 14.

[0044]

Since the present invention is constructed as described above, by raising and lowering the nozzle of the dispenser to the optimum position with respect to the object to be coated, it is ensured that so-called thread dripping occurs in the applied adhesive. This has an excellent effect that it is possible to prevent the nozzle from being interfered with a component already mounted on a substrate or the like and to increase the production efficiency.

[Brief description of the drawings]

FIG. 1 is a sectional view including a partial block diagram showing a dispenser for implementing a control method of the present invention and a control device thereof.

FIG. 2 is a flowchart showing the control method.

FIG. 3 is a sectional view showing a control process of the dispenser.

FIG. 4 is a sectional view showing another example of the conversion mechanism for implementing the control method of the present invention.

FIG. 5 is a sectional view showing still another example of the conversion mechanism.

FIG. 6 is a cross-sectional view showing a process in which an adhesive is normally applied to a substrate surface by a dispenser.

FIG. 7 is a cross-sectional view showing a process in which stringing failure occurs when an adhesive is applied by a dispenser.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Dispenser 12 ... Nozzle 14 ... Syringe 16 ... Servo motor 18 ... Conversion mechanism 20 ... Control device 20A ... Central processing unit 20B ... Man-machine interface 20C ... Memory part 22 ... Application object 36 ... Drive cam follower 38 ... Eccentric rotation cam 40: Cam follower 42: Cam link

Claims (2)

[Claims] 1. A method for controlling a stroke of a dispenser for raising and lowering a syringe having a nozzle for applying an adhesive at a lower end thereof through a conversion mechanism for converting rotation of a motor into vertical movement. A method for controlling a vertical stroke of a dispenser, wherein the vertical and reverse rotation ranges are adjusted in accordance with a moving direction and a forward / reverse rotation range is adjusted according to a vertical movement distance between an application target and the nozzle. 2. The method according to claim 1, further comprising the steps of: reading information on the height and position of the mounted component adhered to the object to be coated with the applied adhesive; and when the cylinder passes the position of the mounted component. A step of comparing the height information and the height of the nozzle to determine whether or not the mounted component interferes with the nozzle; and, as a result of the determination, when the interference occurs, the cylinder is mounted on the nozzle. Driving the motor until it is raised to a height that does not interfere with the parts.