JP2889018B2 - Paste supply device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paste supply apparatus suitably used for supplying paste-like ink to, for example, a screen printer.

[0002]

2. Description of the Related Art Generally, an electric circuit device is manufactured by mounting various circuit elements on a chip formed of a printed circuit board. Recently, however, there is an increasing demand for further improvement in mounting efficiency. In order to meet such a demand, it is required to print a pattern with a paste such as a solder paste, a paste-like resist ink, and an adhesive paste on a chip with high accuracy and efficiently. Usually, screen printing is suitably used for printing a fine pattern using such a paste. However, in order to perform good screen printing, the paste (ink) supplied on the screen must have uniform properties. It is necessary to sufficiently knead the paste and adjust the viscosity of the paste and control the supply amount.

[0003] Conventionally, the paste is supplied to the screen printing machine manually by an operator in most cases. That is, the kneading of the paste is performed by a worker with a spatula, and the adjustment of the viscosity and the supply amount are also performed according to the judgment based on the experience of the worker. Recently, a paste supply device has been proposed in which the paste in a container is pushed out of the container by a piston provided at the top of the container.

[0004]

However, in the manual supply of the paste by the operator, it is extremely difficult to always knead the paste, adjust the viscosity and control the supply amount with the same reproducibility. Because
High reliability cannot be ensured. Further, in the conventional paste supply device, the supply of the paste is merely performed mechanically, the kneading of the paste cannot be actually performed, and the adjustment of the viscosity and the control of the supply amount are almost impossible. There is a problem that there is.

[0005] The present invention solves the above problems,
It is an object of the present invention to provide a paste supply device that can stably achieve kneading, adjustment of viscosity, and control of supply amount with high accuracy, and thus obtain high reliability.

[0006]

According to the present invention, there is provided a paste supply apparatus, comprising: a vertically extending tubular container; a paste supply port formed at a lower end of the container; and a vertically extending paste container. Provided, a paste inlet and a paste outlet are formed at positions vertically separated from each other, a mantle tube having an outer diameter smaller than the inner diameter of the container, and a screw shaft having a spiral groove coaxially disposed in the mantle tube. A spiral pump having a drive motor having a torque sensor, which is provided in connection with a screw shaft of the spiral pump, and in the container,
A piston that moves up and down the annular space around the mantle tube.

[0007]

According to the paste supply device of the present invention, the paste in the container is sufficiently kneaded to be circulated in the container by the spiral pump, and the screw shaft of the spiral pump has a torque of Driven by the drive motor having the sensor, the viscosity of the paste can be detected by the torque sensor.Thus, the viscosity of the paste can be adjusted by controlling the degree of kneading based on the obtained viscosity information. it can. In addition, since the paste in the container is in a uniform and controlled state, the supply amount of the paste can be reliably controlled. The above operation can be stably achieved by the operation of the piston.

[0008]

FIG. 1 is an explanatory sectional view showing an example of a basic configuration of a paste supply device 10 according to the present invention. The paste supply device 10 includes a cylindrical container 11, and the container 11 is basically a cylindrical container body provided to extend in a vertical direction.
12 and an upper cover 13 hermetically connected to the upper portion and having the same inner diameter. At the lower end of the container body 12, a small-diameter vertically extending paste supply tube portion 15 is integrally formed via a conical portion 14, and a paste supply port 16 is formed at the lower end of the paste supply tube portion 15. Is formed. A drive motor 17 having a torque sensor (not shown) is disposed on the upper cover 13 of the container body 12, and a pair of air connectors 18 and 19 are provided.

[0009] In the container 11, along the central axis of the container 11
A cylindrical mantle tube 20 having an outer diameter smaller than the inner diameter of is provided with the upper end thereof fixed to the upper cover 13. The open lower end cylindrical portion of the lower portion 21 of the outer tube 20 in the container main body 12 is fitted to the lower end cylindrical portion of the conical portion 14 of the container main body 12, and the paste supply cylinder is formed through the opening 22. Part 15
Communicates within. At the lower end of the lower portion 21 of the outer tube 20, a paste inlet 23 is formed by a hole penetrating the peripheral wall of the outer tube 20, and at the upper end of the lower portion 21, a paste outlet 24 is formed by a similar through hole. A spiral pump 26 is constituted by the lower portion 21 of the outer tube 20 and a screw shaft 25 provided coaxially therein.

The screw shaft 25 has a spiral blade 28 fixed to a rotating shaft 27 extending in the vertical direction, and a space between the spiral blades 28 forms a spiral groove 29. The upper part of the rotating shaft 27 related to the screw shaft 25 is rotatably supported by a supporting mechanism 31 provided in the upper part 30 of the mantle tube 20, and the upper end thereof is connected to the container 11 via a connecting mechanism 32. Is connected to the drive shaft 33 of the drive motor 17 disposed on the upper cover 13 of the motor.

On the other hand, the lower part of the rotating shaft 27 is
A spiral blade 41 is provided in the paste supply tube portion 15 of the mantle tube 20 so as to protrude downward therefrom, and is provided with a spiral blade 41 in the same direction as the spiral blade 28, thereby forming a paste supply unit 40.

An air piston 50 is provided in the container 11 to move up and down in an annular space formed by the mantle tube 20 while being fitted to the outer peripheral surface of the mantle tube 20. The air piston 50 has a central portion 51 having a conical lower surface that matches the conical portion 14 at the lower end of the container body 12, and an annular outer peripheral edge portion 52 that moves along the inner peripheral surface of the container 11. doing.

An air tube 55 extending from one air connector 18 of the pair of air connectors 18 and 19 forms a lower portion S of an annular space formed in a central portion 51 of the air piston 50.
It is connected to a through hole 53 that opens to the outside. The air tube 55 has a sufficient length to allow the air piston 50 to descend, and when the air piston 50 shown in FIG. 1 is raised, the extra air tube 55 It is housed in an upper portion S2 above the air piston 50. The other air connector 19 communicates with the upper portion S2.

Then, a drive control device having a function of receiving the detected torque signal from the torque sensor of the drive motor 17 and controlling the rotation of the drive motor 17 in response thereto is provided. FIG. 2 shows a configuration of an example of the drive control device. The drive control device of this example includes a drive control unit 60, a display unit 62 and an instruction setting unit 63, a power supply unit (not shown), And a part 66. The drive control unit 60 includes a central processing control unit 71, a drive motor control unit 72, and a current detection unit 73.
And the drive signal DS from the drive motor control unit 72
As a result, the drive motor 17 is driven, and the detected torque signal TS from the torque sensor of the drive motor 17 is fed back to the drive motor control unit 72 as a control signal.

The display section 62 includes, for example, an operable display mechanism 75 for displaying that the apparatus can be operated, a paste shortage display mechanism 76 for indicating a shortage of the amount of paste in the container 11, and a viscosity for displaying the viscosity of the paste. A display mechanism 77 and others are provided, and an instruction setting unit 63 includes a viscosity setting unit 80, an initial supply amount setting unit 81 for paste, and an operation state switching unit 82 for switching between automatic and manual states, and a steady supply amount setting unit. 83 and an operation state switching unit 84 for switching between automatic and manual states are provided.

The compressed air control section 66 has a compressed air source 86 and a switching valve 87, and is a central processing control section of the drive control section 60.
One of the air connectors 18 and 19 of the paste supply device 10 is connected to a compressed air source 86 and the other is connected to the atmosphere via a switching valve 87 by a switching valve control unit 85 operated by a control signal from 71. Let me do. Compressed air source
It is preferable to insert an air filter, a regulator, a pressure gauge, and the like as necessary in the compressed air passage from the switch 86 to the switching valve 87.

In the example shown in FIG. 1, the container main body 12 is made of, for example, resin. In order to securely mount the container main body 12, a metal container main body holding cover 90 detachably fixed to the upper cover 13 is provided. Is provided. Also, the container body 12
It is preferable to provide a heating mechanism for heating the paste therein as necessary. This heating mechanism can be provided, for example, on the container main body holding cover 90.

The paste supply device 10 having the above-described configuration is used.
Works as follows. That is, the container body of the container 11
When the drive motor 17 is driven and the screw shaft 25 is rotated forward via the rotation shaft 27 in a state where the inside of the tube 12 is filled with the paste to be supplied, the paste in the mantle tube 20 causes the spiral blade 28 of the screw shaft 25 to rotate. Then, the paste in the container body 12 is moved upward by the operation of the spiral groove 29, whereby the paste in the container body 12 is introduced from the paste inlet 23 of the mantle tube 20 and rises in the mantle tube 20. It will be discharged into 12. That is, the paste in the container body 12 is circulated by the normal operation of the spiral pump 26, and the container body
The paste in 12 is kneaded to make the paste uniform.

As described above, while the spiral pump 26 is performing the normal rotation operation, in the paste supply cylinder 15,
Since the spiral blade 41 in the same direction as the spiral blade 28 operates in the same direction to raise the paste, the paste does not leak from the paste supply port 16 due to gravity.

The drive motor 17 for driving the spiral pump 26 is provided with a torque sensor. The detected torque signal obtained from the torque sensor has a magnitude corresponding to the load applied to the screw shaft 25. Accordingly, the signal is eventually a signal corresponding to the viscosity of the paste in the mantle tube 20. Therefore, the viscosity of the paste in the container body 12 can be measured by the detected torque signal. When the rotational speed of the screw shaft 25 is increased, for example, the shearing force applied to the paste increases, and the temperature of the paste increases, so that the viscosity of the paste decreases. By controlling the rotation speed of the drive motor 17 by the control device,
The viscosity of the paste in the container body 12 can be adjusted.

When a heating mechanism for the paste in the container body 12 is provided, the above-described drive motor
Since the temperature of the paste can be controlled as an independent factor by controlling the operation of the heating mechanism together with the viscosity adjustment by the control of 17, the adjustment of the viscosity of the paste in the container body 12 can be achieved very efficiently. it can.

Further, the supply of the paste in the container body 12 whose kneading and viscosity have been adjusted as described above is performed by changing the rotation direction of the drive motor 17 and operating the spiral pump 26 in reverse. Can be. At this time,
The paste in the mantle tube 20 will be moved downward,
As a result, the paste in the container body 12 is transferred to the paste inlet 23.
Opening 22 at the lower end of the mantle tube 20, including those introduced from
From the paste supply section 40 of the paste supply section 40, and is pushed out of the paste supply port 16 by the spiral blade 41 and its spiral groove.

Since the amount of the paste supplied from the paste supply port 16 by the reverse operation of the spiral pump 26 corresponds to the rotation speed or time of the spiral pump 26, the reverse operation of the spiral pump 26 is performed. , The amount of paste supplied from the paste supply port 16 can be controlled with high accuracy.

By supplying the paste as described above, the amount of the paste in the container body 12 is reduced. However, since the paste is not highly fluid and has an adhesive property, a part of the paste is attached. The paste remains attached to the inner wall surface of the container body 12. Further, air may be trapped in the upper surface layer of the paste in the container body 12. When such a phenomenon occurs, not only can the paste in the container body 12 not be entirely supplied, but also the kneading of the paste, the adjustment of the viscosity, and the control of the supply amount cannot be performed sufficiently.

However, the air piston 50 is provided in the container 11, and by operating the air piston 50, the above-mentioned phenomenon can be solved. That is, the air connector
Compressed air through 19 through the air piston 50 in the annular space
When the air piston 50 is lowered into the upper portion S2 of the upper part of the container 11, the outer peripheral edge 52 moves along the inner peripheral surface of the container 11, so that the attached paste is scraped off, The shock applied to the upper surface layer of the paste by the air piston 50 causes the air bubbles of the entrained air to be crushed. Thus, the air piston
By the operation of 50, the kneading of the paste in the container body 12, the adjustment of the viscosity, and the control of the supply amount can be reliably achieved.

When the air piston 50 descends, the air in the lower portion S1 of the annular space flows from the upper portion S2 through the through hole 53 formed in the air piston 50 to the air tube.
Although it is released into the atmosphere through 55, it is preferable to provide a ball valve or the like so that the through hole 53 is not closed by the paste. When the air piston 50 rises, conversely, compressed air is introduced into the lower portion S1 of the annular space, and the air in the upper portion S2 is released to the atmosphere.

Since the lower surface of the central portion 51 of the air piston 50 has a conical shape that matches the conical portion 14 at the lower end of the container main body 12, the paste in the container main body 12 is completely discharged, and The inside can be easily emptied. In addition,
It is preferable to prepare a cap for closing the paste supply port 16 when the apparatus is not used.

In order to fill the container body 12 with the paste, for example, a packaging container having the same shape as the separately separated container body 12 is prepared, filled with the paste, and sealed. The container may be mounted on the paste supply device 10 from which the container main body holding cover 90 has been removed, and then the container main body holding cover 90 may be mounted on the upper cover 13. It is preferable that the spiral pump 26 be rotated forward during the operation of mounting the container body 12 filled with the paste.

Although the embodiment of the present invention has been described above, various changes can be made in the present invention. For example, to supply paste from the paste supply port,
The air piston may be lowered without relying on the reverse operation of the spiral pump. In this case, the accuracy of the paste supply amount control is slightly reduced, but is sufficient when strict control is not required. Further, an electric piston can be used instead of the air piston.

[0030]

As described above, according to the paste supply apparatus of the present invention, the paste in the container is circulated in the container by the spiral pump, so that sufficient kneading is achieved, and Since the screw shaft of the pump is driven by a drive motor having a torque sensor, the viscosity of the paste can be detected by the torque sensor, and the viscosity of the paste can be adjusted by the obtained viscosity information. In this way, since the paste in the container is in a uniform and controlled state, the supply amount of the paste can be reliably controlled. The above operation can be stably achieved by the operation of the piston.

[Brief description of the drawings]

FIG. 1 is an explanatory sectional view showing a configuration of an embodiment of a paste supply device of the present invention.

FIG. 2 is a block diagram schematically illustrating an example of a drive control device used in the paste supply device of the present invention.

[Explanation of symbols]

 10 Paste supply device 11 Cylindrical container 12 Container body 13 Upper cover 14 Conical part 15 Paste supply tube part 16 Paste supply port 17 Drive motor 18 Air connector 18 Air connector 20 Mantle tube 21 Lower part 22 Opening 23 Paste inlet 24 Paste Outlet 25 Screw shaft 26 Spiral pump 27 Rotary shaft 28 Spiral blade 29 Spiral groove 30 Upper part 31 Bearing mechanism 32 Connection mechanism 33 Drive shaft 40 Paste feeder 41 Spiral blade 50 Air piston 51 Central part 52 Outer edge S1 Lower part S2 Upper Part 53 Through hole 55 Air tube 60 Drive control unit 62 Display unit 63 Instruction setting unit 66 Compressed air control unit 71 Central processing control unit 72 Drive motor control unit 73 Current detection unit DS Drive signal TS detection torque signal 75 Drivable display mechanism 76 Paste shortage display mechanism 77 Viscosity display mechanism 80 Viscosity setting section 81 Initial supply amount setting section 82 Operating state Valve 90 the container body holding cover switching valve control unit 86 the compressed air source 87 switch instead portion 83 steady supply amount setting unit 84 operating state switching portion 85

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41F 15/40 B01J 4/00 103 B41F 15/08 303 B41F 31/08 G01N 11/14

Claims (2)

(57) [Claims] 1. A vertically extending tubular container, a paste supply port formed at a lower end of the container, and a vertically extending paste inlet provided in the container, and a paste inlet and a paste outlet are vertically separated from each other. Formed in position,
An outer tube having an outer diameter smaller than the inner diameter of the container, and a spiral pump having a screw shaft having a spiral groove disposed coaxially in the outer tube; and a spiral pump provided in connection with the screw shaft of the spiral pump. A paste supply device comprising: a drive motor having a torque sensor; and a piston that moves up and down in an annular space around a mantle tube in the container. 2. A container having a small-diameter cylindrical paste supply cylinder extending vertically at a lower end thereof, and a spiral groove formed in the paste supply cylinder in the same direction as the screw shaft. The paste supply device according to claim 1, wherein