JP2001062992A - Printing agent supply device for screen printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely supply a printing agent onto a mask sheet. SOLUTION: A nozzle 120 for discharging a printing agent onto a mask sheet is provided. A printing agent filling chamber communicating with the nozzle 120 and a printing agent supply unit 103 for supplying the agent to the chamber are provided. A plurality of cylinder chambers communicate with the filling chamber. A pressurizing piston is contained in each cylinder chamber. The piston depresses the agent supplied to the filling chamber. A plurality of the pistons are arranged in a longitudinal direction of the nozzle 120. Thus, vertically moving characteristics of the individual pistons do not depend upon a size of the nozzle 120 in a longitudinal direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing agent supply device for a screen printing machine.

[0002]

2. Description of the Related Art Conventionally, a substrate set on a printing stage is overlaid on a mask sheet of a screen mask for screen printing, and cream solder, conductive paste, resistance paste, or adhesive supplied on the mask sheet is provided. Screen printing machines that print (apply) a printing agent at a predetermined position on a substrate through an opening formed in a mask sheet by expanding the printing agent such as a squeegee are generally known.

In such an apparatus, the squeegee is a plate material in which a forward squeegee and a backward squeegee are combined in pairs, and is made of relatively hard urethane or a special metal.

In recent years, in order to use up the printing agent without waste, a plate-shaped squeegee is assembled in a nozzle shape together with a side plate, and a filling chamber for filling the printing agent is formed between both squeegees. (Japanese Patent Application Laid-Open No. Hei 8-480) discloses a method in which an extruding member that slides is provided so that a printing agent is extruded onto a mask sheet from between squeegees.
No. 24). The extruding member was configured in a plate shape corresponding to the cross-sectional shape of the filling chamber.

[0005]

However, in the above prior art, a plate-like member is employed as the extruding member. Therefore, as the length of the squeegee in the longitudinal direction becomes longer, the squeegee is more likely to be hit. It has been difficult to raise and lower both ends evenly. Therefore, high processing accuracy was required, and the manufacturing cost was increased.

In addition, in a configuration in which plate-shaped squeegees are assembled as a pair, there is a problem in that the ejection performance of the printing agent greatly varies depending on the assembly accuracy, which is not preferable.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a printing agent supply device for a screen printing machine capable of reliably supplying a printing agent onto a mask sheet.

[0008]

According to the present invention, there is provided a printing agent supply apparatus for a screen printing machine for supplying a printing agent onto a mask sheet superimposed on an upper surface of a substrate, wherein the printing agent is supplied onto the mask sheet. A nozzle for discharging, a printing agent filling chamber communicating with the nozzle, a printing agent supply unit for supplying a printing agent to the printing agent filling chamber are provided, a cylinder chamber communicating with the printing agent filling chamber, and a sliding member provided in the cylinder chamber. A plurality of pressurizing pistons movably arranged and capable of pressing down the supplied printing agent are arranged along the longitudinal direction of the nozzle (claim 1).

With this configuration, the printing agent is supplied from the printing agent supply section to the printing agent charging chamber. The printing agent is pushed down by the pressurizing piston. Since a plurality of the pressing pistons are arranged along the longitudinal direction of the nozzle for discharging the printing agent, the lifting and lowering characteristics of each pressing piston are Does not depend on the longitudinal dimension of the nozzle.

In such an apparatus, in particular, each cylinder chamber is connected to a common pressurized fluid supply section.

In this case, a plurality of pressurizing pistons can be simultaneously driven by a single pressurized fluid supply unit.

Further, each pressurizing piston is set so as to be able to descend to the lowermost part of the printing material filling chamber (claim 3).

With this configuration, the pressurizing piston descends to the lowermost portion of the printing material filling chamber, so that substantially all of the printing material supplied to the printing material filling chamber can be discharged to the nozzles.

Further, it is preferable that a detecting means for detecting whether or not each pressurizing piston has risen to a predetermined position is provided.

[0015] In this case, since the printing agent is reduced, when each of the pressurizing pistons is in the printing agent filling state which should be at the ascending position, if any one of the pressurizing pistons drops, This is detected by the detecting means, and predetermined control can be performed. As the detection means, for example,
A light transmission sensor having a photoelectric element facing the longitudinal direction of the nozzle can be exemplified. In addition, the predetermined control includes, for example, notification of running out of printing agent.

Further, it is preferable that an air release hole is provided in the printing agent charging chamber and allows air in the printing agent charging chamber to escape.

With this arrangement, when the printing agent filled in the printing agent charging chamber is supplied to the nozzle, the air in the printing agent charging chamber escapes to the outside through the air escape hole. Discharge becomes smooth.

It is preferable that a driving means for driving the pressure piston at a predetermined timing at a printing interval is provided.

With this arrangement, the pressurizing piston descends at a predetermined timing by the driving means, so that the printing agent pressurized by the corresponding pressurizing piston is stirred, so to speak, to maintain the viscosity. It is preferable that the lowering drive of the pressurizing piston is performed individually at random. For example, the pressurizing pistons may be divided into two groups, and the pressurizing pistons may be driven to descend alternately for each group.

Further, it is preferable that the nozzle is integrally formed with a squeegee-shaped lip which slidably contacts the mask sheet and discharges the printing agent.

In this manner, the lip of the nozzle acts as a squeegee, slides on the mask sheet, and prints a printing agent on the substrate mounted on the mask sheet.

In addition, the nozzle is held on a lower surface of the printing agent filling chamber via a detachable nozzle holder, and is joined to a slope formed on the nozzle holder, so that the nozzle is connected via the nozzle holder. It is preferable that a fastening member that fastens the nozzle in a wedge shape while maintaining the liquid tightness in the printing agent filling chamber is detachably provided (claim 8).

With this arrangement, the nozzle is tightened in a wedge shape via the nozzle holder, and the nozzle is mounted while maintaining good liquid tightness. Further, since the fastening member is configured to be detachable, the nozzle can be easily attached and detached.

[0024]

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

FIG. 1 is an exploded perspective view showing a main part of the present invention, and FIG. 2 is a schematic side view of the screen printing machine of FIG. First, referring to FIG. 2, a loading conveyor 2a and a loading conveyor 2b for loading and unloading a printed circuit board W are mounted on a base 2 of the screen printing machine 1 with a printing stage 3 described later in detail interposed therebetween. It is arranged on both sides (left-right direction in FIG. 2; in this embodiment, “X-axis direction”). Above the printing stage 3, a sheet holding unit 53 for stretching the mask sheet 51 of the screen mask 50 mounted on the printed board W, and a printing unit 60 arranged above the held mask sheet 51
(See FIG. 1), and screen printing is performed by the printing unit 60 on the printed circuit board W mounted on the mask sheet 51 by the printing stage 3 as described later.

The printing stage 3 includes a fixed table 4 installed at a fixed position on the base 2 and a fixed table 4
In contrast, a Y-axis table 6 that can be relatively displaced in the left-right direction of FIG. 1 (“Y-axis direction” in this embodiment) via a pair of rails 5 and a ball screw unit 15, X-axis table 8 that can be relatively displaced in the X-axis direction via a pair of rails 7 and ball screw unit 17
An R-axis table 10 rotatable around a vertical line (“Z-axis direction” in this embodiment) via a rotation unit 9 provided on the X-axis table 8; A lifting table 12 which can be moved up and down relatively via a ball screw unit 11. A clamp unit 20 is attached to the lifting table 12. The ball screw units 11, 15, 17
The rotation unit 9 is driven by a servomotor.

The clamp unit 20 has a pair of clamp pieces 24a and 24b. Each clamp piece 24a,
Reference numeral 24b denotes a substantially plate-shaped member extending in the X-axis direction, one of which is made movable by a belt driving mechanism (not shown), and which cooperates with the other of the fixed side to move the printed circuit board W loaded from the loading conveyor 2a. It constitutes the clamp 24 to be sandwiched.

A pin unit 25 is provided between the clamp pieces 24a and 24b. Although illustration is omitted, the pin unit 25 includes the clamp pieces 24a and 24b.
Is configured to be relatively vertically movable. Thereby, each clamp piece 24a,
When the printed circuit board W is carried in between 24b, the lower surface thereof is received by the pins 25a of the pin unit 25, the printed circuit board W is temporarily placed, and the printed circuit board W is temporarily held in cooperation with pressing means (not shown). , And the clamp 24.

When the printed board W is transferred to the clamp 24, the elevating table 12 of the printing stage 3 is raised, and the mask sheet 51 of the screen mask 50 is moved.
The printed circuit board W is mounted on the lower surface. A printing agent such as cream solder is applied to the overlaid printed circuit board W by the printing unit 60 described below.

The printing unit 60 is located above the base 2 and is mounted on a horizontal frame 2c that is laid horizontally in the X-axis direction. The horizontal frame 2c is configured to be movable in the Y-axis direction by a pair of rails, and is reciprocated in the Y direction by a ball screw mechanism (not shown). Thereby, a printing agent supply device 61 described later in detail can be reciprocated on the screen mask 50.

Referring to FIG. 1, the printing unit 60 includes a printing agent supply device 61, a holder 63 for holding the printing agent supply device 61, and an elevating device for raising and lowering the printing agent supply device 61 via the holder 63. And a unit 64,
The body frame 65 of the lifting unit 64 is fixed to the horizontal frame 2c (see FIG. 2).

FIG. 3 is a perspective view of a printing agent supply device 61 according to the screen printing machine of FIG. FIG. 4 is a plan view of a printing agent supply device 61 according to the screen printing machine in FIG.
FIG. 5 shows a printing agent supply device 6 according to the screen printing machine of FIG.
1 and FIG. 6 and FIG. 7 are cross-sectional views of a printing agent supply device 61 according to the screen printing machine of FIG.

With reference to these figures, the printing agent supply device 61 according to the present embodiment has a substantially long base plate 10.
1 is provided. At the center of the base plate 101,
A mounting portion 102 protruding from one end side in the width direction is extended, and a printing material supply cylinder (printing material supply source) 103 is erected on the mounting portion 102.

Inside the printing agent supply cylinder 103, a piston 103a in a substantially top shape is provided, and this piston 103a is connected to a pressurized air supply device (pressurized fluid supply unit) 1
By lowering with the pressurized air from 04, the printing agent inside can be discharged.
As shown in FIGS. 3, 6 and 7, a passage forming block 105 and a cylinder block 106 which are joined to each other in a detachable manner are fixed to a lower surface of the base plate 101 by bolts (not shown).

The passage forming block 105 is disposed on the lower surface of the mounting portion 102, and has an upper end communicating with the discharge port 103b of the cylinder 103. The printing material filling path 105a which opens to the side is defined.

The cylinder block 106 extends substantially along the entire length of the base plate 101 in the longitudinal direction.
The interior thereof defines a filling chamber 106a along the longitudinal direction of the base plate 101, and a communication path 106b that communicates the filling chamber 106a with the printing agent filling path 105a. The filling chamber 106a is provided with a plurality of vertical cylinder chambers 107 communicating with the lower surface of the base plate 101. These cylinder chambers 107 are equally arranged along the longitudinal direction of the base plate 101, and are provided symmetrically along the center line O of the base plate 101, for example, in groups of five (hereinafter, denoted by suffixes A and B). I have. A pressurizing piston 108 is provided in these cylinder chambers 107. Each pressurizing piston 108 has a filling chamber 106a
This is for pressurizing the printing agent filled therein by its own weight. Each pressurizing piston 108 has a rod 108a
Is provided concentrically. Each rod 108a protrudes above the base plate 101, and is prevented from coming off by a head 108b formed on the upper part thereof.

As shown in FIG. 3, the base plate 101
At both ends in the longitudinal direction, via the mounting member 109,
A light transmission sensor S having a light receiving element S1 and a light emitting element S2 as main elements is attached.
08 head 108b has a predetermined height h1 (FIG. 6).
) Can be detected when it falls. In the illustrated embodiment, when at least one of the pressure pistons 108 is detected to be lowered by the light transmission sensor S, the control device 140 connected to the light transmission sensor S detects a supply failure or printing agent. It is set so that the inside of the supply cylinder 103 is determined to be empty and this is notified.

A group 107A, 107 of each cylinder chamber 107
B, on the lower surface of the base plate 101,
A pair of manifolds 110A and 110B are provided on the opposite side of the passage forming block 105. Each of the manifolds 110A and 110B has a corresponding group 10
Communication passage 1 communicating with cylinder chamber 107 of 7A, 107B
10a and 110b are defined.
a, 110b are connected to corresponding cylinder chambers 107A, 107A through communication passages 106c formed in the cylinder block 106.
07B, the corresponding group 107A,
The pressurized piston 10 in the cylinder chamber 107 of 107B
Pressurized air can be supplied to a section defined between the base plate 8 and the base plate 101. In the illustrated embodiment, as shown in FIGS. 3 to 5, an air release hole 101 a is formed in the base plate 101, and the air release hole 101 a is provided in the printing agent filling chamber 106.
It communicates with both ends of a.

As shown in FIG. 3, each manifold 110
A and 110B are connected to a pressurized air supply device 104, and the pressurized air supply device 104 can selectively supply pressurized air to each of the manifolds 110A and 110B.

Referring to FIGS. 6 and 7, a nozzle 120 is attached to the lower surface of the other cylinder block 106. The nozzle 120 is a rubber member that also functions as a squeegee in the present embodiment, has a long plate-shaped outer shell, and communicates with the filling chamber 106a and the cylinder chamber 107A (107B).
0a, flange portion 121, and flange portion 121
And a lip 122 that extends from a lower portion of the printer and that defines a discharge port 120b that discharges the printing agent introduced into the introduction section 120a. Then, the lip 122 can function as a squeegee by making the lip 122 always contact the mask sheet 51 (see FIGS. 8A and 9B).

In order to fix the rubber nozzle 120 to the cylinder block 106, the nozzle 120 is held by a nozzle holder 130 in this embodiment. The nozzle holder 130 has a housing recess 131 along the outer shape of the flange portion 121 of the nozzle 120. The nozzle holder 130 houses the nozzle 120 inside the housing recess 131. The lip 122 of 120 faces downward.

The nozzle holder 130 is fixed to the cylinder block 106 by a mounting frame 134. The mounting frame 134 includes a bolt 135
, So that the nozzle holder 130 (and the nozzle 120) can be easily assembled and disassembled. In the illustrated embodiment, a flange portion 106d for attachment is formed on a long side of the cylinder block 106, and a jaw portion 134a for sandwiching the flange portion 106d and the long edge of the nozzle holder 130 is formed on the attachment frame 134. Is formed. Here, the long edge of the nozzle holder 130 forms a wedge-shaped slope 136 by chamfering.
At the same time, the jaw 1 of the mounting frame 134 is
34a is formed on the slope 136 via the nozzle holder 130.
Cooperates with this to constitute a fastening member for fastening the nozzle 120 to the lower surface of the cylinder block 106 in a wedge shape. As a result, the nozzle 120 is mounted in the printing agent filling chamber while maintaining the liquid tightness. Further, since the mounting frame 134 as a fastening member is configured to be detachable, the nozzle 120 can be easily attached and detached (see FIG. 7).

FIGS. 8A and 8B are schematic cross-sectional views schematically showing main parts of the printing unit 60. FIG. 8A is a state in which the printing agent supply device 61 is lowered to the mask sheet 51, and FIG. The state where the apparatus 61 is lifted from the mask sheet 51 is shown.

Referring to FIG. 1 and FIG. 8A, the above-described printing agent supply device 61 is attached to the rod end (lower end) of an air cylinder 61a fixed to a holder 63 via a base plate 101. The air cylinder 61a is supported so as to be able to move up and down with respect to the holder 63 by operation of the air cylinder 61a. The stroke of the air cylinder 61a is set so that the printing agent supply device 61 can land on the mask sheet 51 when extended to the bottom dead center. In FIG. 1, 61e and 62e are guide rods which are paired on both sides of the air cylinder 61a.

As shown in FIG. 1, the lifting unit 64
Is for adjusting the landing load of the printing agent supply device 61 by raising and lowering the entire holder 63, and contributes to the adjustment of the printing pressure of the printing agent supply device 61 during printing. A servo motor 66, a timing belt 67 connected to the servo motor 66, a ball screw 68 rotationally driven via the timing belt 67, and an elevator connected to the ball screw 68 are provided on a frame 65 of the lifting unit 64. 69. Servo motor 66,
Each of the ball screws 68 has a vertically extending axis.
When the servo motor 66 drives the ball screw 68 to rotate, the elevator 69 moves up and down.

A spring holder 70 is fixed to the lift 69 shown in the figure. This spring holder 70
This is for holding the upper end of the compression spring 71 that urges the holder 63 in the direction of pushing down. On the other hand, the holder 63
A spring holder 72 for holding the lower end of the compression spring 71 is fixed to the back of the holder.
By interposing the compression spring 71 between 0 and 72, the lifting drive force of the lifter 69 is elastically transmitted to the printing agent supply device 61 via the holder 63. The compression spring 71 and the lifting element 69 constitute a pressing unit that presses the nozzle 120 (see FIG. 8) of the printing agent supply device 61 against the mask sheet 51. In the illustrated embodiment, a pressure receiving plate 63a is provided on the rear surface of the holder 63 so as to project therefrom. The pressure receiving plate 63a faces above the spring holder 72 in the vertical direction. And FIG. 8 (B)
As shown in the figure, in the range of the supply device vertical stroke ST2 that has passed the switching position P after the elevating element 69 has risen and passed the fixed spring pressing stroke ST1, the spring holder 70 contacts the lower surface of the pressure receiving plate 63a. And holder 63
Is configured to directly raise and lower the printing agent supply device 61 via the. In the illustrated embodiment, the lift 69 is vertically guided by a rail 69a, and an upper limit of the lift 69 is defined by a stopper 69b provided at an upper end of the guide rail 69a ( (See FIG. 1).

On both sides of the ball screw 68, a pair of guide rails 83 and 84 are provided in parallel along the vertical direction, and the sliders 83a and 84 of the respective guide rails 83 and 84 are provided.
Since a is fixed to the back of the holder 63, the power of the elevating element 69 can be smoothly transmitted to the holder 63. Further, a pair of spring seats 85, 86 disposed at the lower end of the frame 65 are provided on both outer sides of the guide rails 83, 84, respectively. Each of the spring seats 85 and 86 is for supporting a lower end of a canceling compression spring 89 or 90 interposed between a pair of spring holders 87 and 88 fixed to both sides of the holder 63. , The canceling compression springs 89, 9
0 urges the holder 63 upward, and the holder 63
Also, the load due to the weight of the member attached thereto is canceled. As a result, the printing material supply device 61 is elastically moved by the biasing force of the compression spring 71.
Will land on the mask sheet 51.

As shown in FIGS. 8A and 8B, a load cell 61c is attached to a rod 61b of an air cylinder 61a to detect a landing load of the printing agent supply device 61. The device 61 is a mask sheet 5
The load (or printing pressure) at the time of landing at No. 1 can be individually detected.

FIG. 9 is a view showing a printing process of the screen printing machine 1 according to the embodiment of FIG.

First, referring to FIG. 2 and FIG. 9A, in the above configuration, the printed board W is loaded from the loading conveyor 2a, and the printed board W is clamped by the clamp 24 of the printing stage 3. . Next, the printing stage 3 conveys the printed board W below the mask sheet 51, raises the elevating table 12 of the printing stage 3, and loads the printed board W on the lower surface of the mask sheet 51.

When the printed board W is mounted on the mask sheet 51, the elevating unit 64 of the printing unit 60 lowers the holder 63 and is reciprocated along the X-axis direction. At this time, the lip 122 of the nozzle 120 attached to the printing agent supply device 61 is always placed on the mask sheet 51.
By landing and sliding, the printing agent on the mask sheet 51 is expanded, and a printing operation is performed (FIG. 8A).
reference).

Referring to FIGS. 3 and 6, printing unit 6
In the preparatory stage before printing, the control device 140 activates the pressurized air supply device 104 to pressurize the piston 103a of the printing material supply cylinder 103 to fill the printing material inside the printing material supply device 61 with the printing material. The chamber 106a is filled. As a result, the printing agent pushes the piston 108 upward against the weight of the piston 108, and the filling chamber 106a
Is filled in. As a result, the printing agent is introduced into the introduction portion 120a of the nozzle 120, and the ejection agent 1 of the lip 122
20b is ready to be ejected.

Next, at the time of printing, the control device 140
Drives the pressurized air supply device 104 to supply pressurized air to each of the manifolds 110A and 110B, sends pressurized air to each cylinder chamber 107, and pushes down the pressurized cylinder 108. As a result, the printing agent is constantly discharged from the nozzle 120 by a proper amount while being pressed by the pressing piston 108, and is expanded on the mask sheet 51 by the lip 122.

When the printing process is completed, the printing stage 3 lowers the printed substrate W on which printing has been completed, peels it off the mask sheet 51, sends it out to the carry-out conveyor 2b, and receives the next printed substrate W, as described above. Repeat the work. Until the next printed circuit board W is set, also in the printing material supply device 60, the control device 140 operates the pressurized air supply device 104 to operate the cylinder 103a in the printing material supply cylinder 103.
Is pressed down, and the above-described printing agent supply step is repeated. At this time, any of the pressurizing pistons 108
However, if the printing agent is filled with the desired printing agent and remains there without being completely raised, the light transmission sensor S detects this, and the control device 140 determines that the printing agent supply is insufficient, and performs predetermined control ( For example, notification of a supply failure) can be performed.

Further, when the interval until the next printing is long (for example, between the work time in the morning and the work time in the afternoon), the pressurized air supply device 104 pressurizes the pair of manifolds 110A and 110B. By supplying air alternately, each manifold 110A, 11
The piston 108 corresponding to OB is pressurized downward by the pressurized air, and the printing agent can be pushed into the inlet 120 a of the nozzle 120.

As described above, in the above-described embodiment, the lifting / lowering characteristics of the pressurizing piston 108 for pressing the printing agent do not depend on the longitudinal dimension of the nozzle 120, so that the squeegee can be relatively long. It is possible to cope with inexpensive costs, and it is possible to reliably prevent defective supply of the printing agent.

In particular, since each pressurizing piston 108 is connected to the common manifold 110A (110B),
The plurality of pressurizing pistons 108 are connected to a single pressurized air supply device 1
As a result, the plurality of pressurizing pistons 108 can be driven with a relatively compact and simple configuration, which contributes to downsizing and cost reduction of the apparatus.

In addition, since each pressurizing piston 108 is set at the lowermost portion of the printing agent charging chamber 106a, almost all of the printing agent supplied to the printing agent charging chamber 106a is
Thus, the supplied printing agent can be used up almost without waste.

Further, since the light transmission sensor S is provided as a detecting means for detecting whether or not all the pressure pistons 108 have risen, all the pressure pistons 108 can be detected.
If any one of the pressurizing pistons 108 falls when should be in the ascending state, the light transmission sensor S detects this and makes it possible to perform a predetermined control. Can be performed.

Further, since the air release hole 101a is provided in the printing material filling chamber 106a, the discharging of the printing material from the nozzle 120 becomes smooth, so that the printing material can be more reliably discharged.

In addition, driving means (manifold 110) for lowering the pressurizing piston 108 during the printing interval
A, 110B), the printing agent pressurized by the driven pressurizing piston 108 is agitated so as to maintain the viscosity, so that the life of the printing agent is prolonged and the maintainability is improved. .

Further, the nozzle 120 is connected to the mask sheet 51.
Since the lip 122 is in sliding contact with the lip 122, the lip 122 can be used as a squeegee to apply a printing agent. As a result, the number of parts can be reduced, and screen printing can be performed with a simpler configuration.

The nozzle 120 is connected to the printing agent filling chamber 1.
06a is held on the lower surface of the nozzle holder 130 via a detachable nozzle holder 130, and is joined to a slope formed on the nozzle holder 130, thereby forming the nozzle holder 13
The nozzle 120 is detachably provided with a fastening member (a jaw 134a of the mounting frame 134) for fastening the nozzle 120 in a wedge shape while maintaining the liquid tightness in the printing agent filling chamber 106a through the nozzle 0. And the maintainability is further improved.

The above embodiment is merely an example of a preferred specific example of the present invention, and the present invention is not limited to the above embodiment.

For example, the nozzle 120 may be made of a material (eg, metal) other than rubber. Alternatively, an air cushion cylinder or the like can be used instead of the springs 71, 89, and 90 described above.

It goes without saying that various modifications are possible within the scope of the claims of the present invention.

[0067]

As described above, according to the present invention,
Since the lifting and lowering characteristics of the pressurizing piston that pressurizes the printing agent do not depend on the length of the nozzle in the longitudinal direction, it is possible to cope with a relatively long squeegee at a low cost, and to ensure that the printing agent is not supplied properly. Can be prevented.

In particular, when each pressurizing piston is connected to a common pressurized fluid supply unit, a plurality of pressurized pistons can be simultaneously driven by a single pressurized fluid supply unit. A plurality of pressurizing pistons can be driven with a relatively compact and simple configuration, contributing to downsizing and cost reduction of the device.

Further, when the bottom dead center of each pressurizing piston is set at the bottom of the printing material filling chamber, it is possible to discharge substantially all of the printing material supplied to the printing material filling chamber to the nozzles. Therefore, the supplied printing agent can be used up almost without waste.

When a detecting means is provided for detecting whether or not all of the pressurizing pistons have risen at once, if any one of the pressurizing pistons has fallen, this is detected. Since the means can detect and perform a predetermined control, a more reliable pressurization control can be performed from this point regardless of the longitudinal dimension of the nozzle.

Further, in the case where an air escape hole is provided in the printing material filling chamber, the discharging of the printing material from the nozzle becomes smooth, so that the printing material can be more reliably discharged from this point. Can be.

In addition, when a driving means for lowering the pressurizing piston at a predetermined timing during the printing interval is provided, the printing agent pressurized by the driven pressurizing piston is stirred, so to speak, to maintain the viscosity. As a result, the life of the printing agent is extended, and the maintainability is also improved.

Further, in the case of a lip in which the nozzle slides on the mask sheet to discharge the printing agent, the printing agent can be printed using the nozzle outlet as a squeegee, so that the number of parts can be reduced and a simpler configuration can be achieved. Can be used for screen printing.

The nozzle is held on the lower surface of the printing agent charging chamber via a detachable nozzle holder, and is joined to a slope formed on the nozzle holder, so that the nozzle is connected via the nozzle holder. When the printing material filling chamber is provided with a detachable fastening member for fastening in a wedge shape while maintaining the liquid tightness, the nozzle can be easily attached and detached, and the maintainability is further improved.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a main part of the present invention.

FIG. 2 is a schematic side view of the screen printing machine of FIG.

FIG. 3 is a perspective view of a printing agent supply device according to the screen printing machine of FIG. 1;

FIG. 4 is a plan view of a printing agent supply device according to the screen printing machine of FIG. 1;

FIG. 5 is a bottom view of the printing agent supply device according to the screen printing machine of FIG. 1;

FIG. 6 is a sectional view of a printing agent supply device according to the screen printing machine of FIG. 1;

FIG. 7 is a sectional view of a printing agent supply device according to the screen printing machine of FIG. 1;

FIG. 8 is a schematic cross-sectional view schematically showing a main part of a printing unit, wherein (A) shows a state in which a squeegee is lowered to a mask sheet, and (B) shows a state in which the squeegee is raised from the mask sheet. Each is shown.

FIG. 9 is a diagram illustrating a printing process of the screen printing machine according to the embodiment of FIG. 1;

[Explanation of symbols]

 1 Screen Printing Machine 51 Mask Sheet 60 Printing Unit 61 Printing Agent Supply Device 103 Printing Agent Supply Cylinder (Printing Agent Supplying Unit) 107a Printing Agent Filling Room 108 Pressurizing Piston 110A, 110B Manifold 120 Nozzle 120b Discharge Port 122 Lip 130 Nozzle Holder 134 Mounting frame (clamping member) 136 Slope 140 Control device W Printed circuit board

Claims (8)

[Claims] 1. A printing agent supply device for a screen printing machine for supplying a printing agent onto a mask sheet overlaid on an upper surface of a substrate, wherein the nozzle communicates with the nozzle for discharging the printing agent onto the mask sheet. A printing material supply chamber for supplying the printing material to the printing material filling room, a cylinder chamber communicating with the printing material filling chamber, and a cylinder chamber slidably provided and supplied to the cylinder chamber. A pressurizing piston capable of depressing the printing agent is provided in plurality along the longitudinal direction of the nozzle, the printing agent supply device for a screen printing machine. 2. The printing agent supply device for a screen printing machine according to claim 1, wherein each cylinder chamber is connected to a common pressurized fluid supply unit. 3. The printing material supply device for a screen printing machine according to claim 1, wherein each pressurizing piston is set so as to be able to descend to a lowermost portion of the printing material filling chamber. 4. The screen according to claim 1, further comprising detection means for detecting whether or not each of the pressure pistons has risen to a predetermined position. Printing agent supply device for printing press. 5. The screen printing machine according to claim 1, further comprising an air release hole provided in the printing agent charging chamber and for releasing air in the printing agent charging chamber. Printing agent supply device. 6. The printing agent supply device for a screen printing machine according to claim 1, further comprising a driving unit that drives the pressure piston at a predetermined timing during a printing interval. 7. The screen printing machine according to claim 1, wherein said nozzle is formed integrally with a squeegee-shaped lip which slides on a mask sheet to discharge a printing agent. Printing agent supply device. 8. The nozzle is held on a lower surface of a printing agent filling chamber via a detachable nozzle holder, and is joined to an inclined surface formed in the nozzle holder, so that the nozzle is inserted through the nozzle holder. The printing agent supply device for a screen printing machine according to any one of claims 1 to 7, further comprising a wedge-shaped fastening member for detachably mounting the printing agent in a printing agent filling chamber while maintaining liquid tightness. .