JP2001030463A - Apparatus and method for cream solder printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for cream solder printing capable of stably printing even in the case of accelerating a printing time. SOLUTION: The apparatus 10 for cream solder printing comprises a pressure generating member 28 provided near ends of squeegees 21a, 21b to form a narrow passage to a printing mask 3 and to form a channel between the squeegees 12a and 12b when printed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cream solder printing apparatus and a printing method for printing and applying cream solder on a circuit board, which is an object to be printed.

[0002]

2. Description of the Related Art Conventionally, cream solder is mainly used for soldering electronic components such as chip components on a printed circuit board in the manufacture of an electronic circuit board, and the cream solder is printed and applied in a desired pattern. For this purpose, a cream solder printing apparatus is used. FIG. 12 shows an example of a squeegee head mounted on a conventional cream solder printing apparatus.
The structure shown in FIG.

Usually, the printing operation is performed by the squeegee head 102.
Move alternately from left to right and from right to left in FIG. 12 for each printed circuit board 5. At this time, in the rightward printing from left to right, the rightward printing squeegee 101a
However, in the opposite leftward printing, the leftward printing squeegee 101
b is used.

[0004] Such a conventional cream solder printing apparatus 1
The printing operation of cream solder on the printed circuit board 5 according to 00 will be described with reference to FIGS. 12 to 1
In 4, reference numeral 3 denotes a printing mask on which an opening 4 having a desired pattern is formed, 5 denotes a printed board, 6 denotes a land on which a cream solder 7 is printed, and 8 denotes a solder resist. The desired pattern of the printing mask 3 refers to a pattern in which the openings 4 are formed corresponding to the lands 6 on the printed board 5.

First, when the rightward printing is performed, the printed circuit board 5 is positioned on the printing mask 3 so that the openings 4 and the lands 6 coincide with each other, and then the leftward printing squeegee 101b is raised. In this state, the rightward printing squeegee 101a is lowered to bring the squeegee tip 103 into contact with the surface 3a of the printing mask 3 at an appropriate printing pressure.

In this state, the cream solder 7 previously provided on the surface 3a of the printing mask 3 is filled in the opening 4 of the printing mask 3 by moving the right printing squeegee 101a linearly along the right direction. Let me do it. After the rightward printing squeegee 101a moves to the right end of the printing mask 3,
The printing operation ends when the printed board 5 is separated from the printing mask 3.

When performing the leftward printing, similarly to the rightward printing described above, the printed circuit board 5 is positioned on the printing mask 3 and overlapped, and then the rightward printing squeegee 101a is reversed. The leftward printing squeegee 101b is lowered while the squeegee tip 10 is raised.
3 is brought into contact. The subsequent operation is the same as the above-described rightward printing.

As described above, these operations are alternately repeated for each printed circuit board 5, so that the cream solder 7 is placed on the lands 6 of each printed circuit board 5 via the printing mask 3.
Is continuously printed and applied.

In printing using the conventional cream solder printing apparatus 100, the front end 103 of the printing squeegee 101a or the printing squeegee 101b is attached to the surface 3 of the printing mask 3.
a with the printing squeegee 10 in contact with a
1a or the printing squeegee 101b is moved, as shown in FIG.
101b is a type of squeegee that performs two operations of a scraping operation of scraping the cream solder 7 on the surface 3a of the printing mask 3 and a filling operation of filling the opening 4 of the printing mask 3 with the cream solder 7. ing. FIG. 13 and FIG.
4 will be described.

FIGS. 13 and 14 are enlarged views of the printing squeegee 101a and the like in the case of rightward printing. First, as shown in FIG.
When the right-direction printing squeegee 101a descends and moves linearly along the right direction so as to contact the right-direction printing squeegee 101a, the right-direction printing squeegee 101a reaches the cream solder 7 supplied to the surface 3a of the printing mask 3. It moves while scraping it.

This scraping operation allows the cream solder 7 to be removed.
Flows while performing a rotational movement called rolling, as shown by an arrow I in FIG. At this time, fluid pressure is generated inside the cream solder 7.

In this state, when the rightward printing squeegee 101a further moves rightward and reaches the opening 4 of the printing mask 3, the cream solder 7
Is pushed into the opening 4 to form a so-called cream solder 7.
Is filled. Hereinafter, the pressure at which the cream solder 7 is pushed into the opening 4 is referred to as a filling pressure.

[0013]

On the other hand, it is desired to reduce the printing time in the cream solder printing step from the viewpoint of improving productivity. However, in the conventional cream solder printing apparatus 100, when the moving speed (squeegee speed) of the squeegee 101a is increased to shorten the time, as shown in FIG. Insufficiency of the filling amount of the solder 7, that is, a so-called unfilled portion 9 occurs, resulting in poor printing, and stable printing cannot be performed. The reason is as follows.

When the squeegee speed is increased, the time during which the leading end 103 of the printing squeegee 101a passes over the opening 4 becomes shorter. Therefore, the time for filling the opening 4 with the cream solder 7 (hereinafter, referred to as filling time) is naturally shortened. In order to investigate this phenomenon, as shown in FIG. 15, a pressure sensor 51 is arranged on the back surface of the printing mask 3, an opening is provided in the printing mask at a corresponding position, and the squeegee is moved at a moving speed of 40 mm / sec and 200 mm / sec. The filling pressure at the time of moving in sec was measured. FIG. 16 is a graph showing the measurement results. The time t on the horizontal axis is the time for the squeegee to pass over the pressure sensor, and the filling pressure P is the pressure detected by the pressure sensor via the cream solder when the squeegee passes over the pressure sensor. From this graph, it can be clearly understood that the filling time is shortened when the moving speed of the squeegee is increased.

When the squeegee speed is increased, the filling pressure itself increases. However, the time required for the squeegee tip 103 to pass over the opening 4 is shortened. A short filling time cannot be obtained. As a result, an unfilled portion 9 occurs.

As described above, the conventional cream solder printing apparatus cannot achieve both high printing speed and stable printing.

An object of the present invention is to solve the above-mentioned conventional problems, and to provide a cream solder printing apparatus and a printing method capable of performing stable printing even when the printing time is shortened. Is to do.

[0018]

The above object of the present invention is achieved by the following constitution. By moving the squeegee in the printing direction on the surface of the printing mask in which the opening is formed, the cream solder supplied on the front surface passes through the opening to the circuit board surface located on the back surface of the printing mask. In a cream solder printing apparatus that prints and applies, a narrow path is formed between the printing mask and the printing mask during printing, and a pressure generating member that forms a flow path between the printing mask and the squeegee extends over the vicinity of the tip of the squeegee. A cream solder printing device, comprising:

[0019] The cream solder printing apparatus as described above, wherein the pressure generating member is a round bar.

The cream solder printing apparatus according to the above or the above, wherein the pressure generating member has a built-in heating element.

The cream solder application apparatus according to any one of the above-mentioned items, wherein the squeegee is provided in a pair and is always in contact with the printing mask at least during printing.

The cream solder printing apparatus according to any one of the above-mentioned items, wherein the narrow path has a wedge-shaped cross section that narrows toward the squeegee.

The height of the pressure generating member from the surface of the printing mask is lower than the rolling height of the cream solder during printing, and the pressure generating member is buried in the cream solder during rolling during printing. The cream solder printing apparatus according to any one of the above-mentioned items, wherein

[0024] The cream solder printing apparatus according to any one of the above-mentioned items, wherein the pressure generating member is fixed so as not to rotate.

When the squeegee moves in the printing direction on the surface of the printing mask in which the opening is formed, the cream solder on the surface is transferred to the circuit board surface located on the back surface of the printing mask through the opening. In the cream solder printing method of performing printing and applying, the printing and applying are performed while increasing the pressure of the cream solder flowing between the print mask and the pressure generating member provided near the tip of the squeegee. Cream solder printing method.

[0026]

According to the above arrangement, the pressure of the cream solder flowing between the pressure generating member and the printing mask is increased by the movement of the squeegee during printing, and the increased pressure causes the cream solder to flow. More downwards flow is filled into the openings of the printing mask. Since the pressure generating member forms a narrow path between the pressure generating member and the mask surface, the cream solder flowing between the pressure generating member and the mask surface maintains a high pressure state for a long time.

Therefore, even if the squeegee speed is increased, the opening can be filled with the cream solder satisfactorily by the increased filling pressure.

Further, according to the above configuration, since the pressure generating member is made of a round bar, there is no need to perform complicated machining on the material in the production of the pressure generating member, and the pressure generating member can be formed with a simple configuration. Therefore, the pressure generating member can be provided without increasing the manufacturing cost.

Further, according to the above configuration, since the pressure generating member has a built-in heating element, the temperature of the cream solder can be kept constant, and as a result, the viscosity of the cream solder is kept constant. Thus, certain printing characteristics can be obtained.

Further, according to the above configuration, a pair of squeegees are provided, and at least during printing, the squeegee is always in contact with the print mask. A set amount of cream solder can always be stored on the top. Further, since the squeegee does not move up and down during printing, the printing time can be shortened and the productivity can be improved. Further, since there is no sealed portion, when a squeegee or the like is cleaned, it can be easily cleaned.

Further, according to the above configuration, since the narrow path has a wedge-shaped cross section, the cream solder is efficiently introduced into the inclined surface, and the cream solder flows between the pressure generating member and the printing mask surface. Can be increased efficiently. Further, according to the above configuration, the height of the pressure generating member from the surface of the printing mask is lower than the rolling height of the cream solder during printing, and the pressure generating member is placed in the cream solder during rolling during printing. Since it is buried, the pressure of the cream solder flowing between the pressure generating member and the printing mask surface can be increased without adversely affecting the rolling of the cream solder. Further, according to the above configuration, since the pressure generating member is fixed so as not to rotate, it can be attached with a simple configuration.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. A cream solder printing apparatus and a printing method according to an embodiment of the present invention will be described below with reference to the drawings. The printing method is executed by the cream solder printing apparatus. In each of the drawings, components that perform the same or similar functions have the same reference characters allotted, and description thereof will not be repeated. In this specification, cream solder refers to paste solder in which powder solder is mixed with high-viscosity flux.

FIG. 1 is a schematic diagram showing the periphery of a squeegee in a cream solder printing apparatus 10 according to the present embodiment. The cream solder printing apparatus 10 is of a type in which a pair of squeegees move in the above-described left and right printing directions. The cream solder printing apparatus 10 includes a squeegee 12a used for the rightward printing and a squeegee 12b used for the leftward printing.

At the time of printing, the squeegee 1 fills the opening 4 of the printing mask 3 with the cream solder 7 and scrapes the cream solder 7 on the printing mask 3.
The squeegee vertical drive units 16 and 18 attached to the squeegee head base plate 14 of the cream solder printing apparatus 10 respectively serve between the standby position 20 and the operation position 22. It can be moved up and down. The squeegees 12a and 12b are formed in a plate shape, and are made of hard rubber such as urethane rubber, for example.

The base plate 14 is moved in the left and right printing directions by a driving device 26 whose operation is controlled by a control device 24. FIG. 1 shows a state in which printing in the right direction is being performed, and thus a state in which one squeegee 12a has been lowered to an operation position 22 where filling and scraping is performed, and the other squeegee 12b has been raised to a standby position 20. Is shown.

In the state where the squeegees 12a and 12b are located at the operation position 22, the tip of each squeegee is placed under such a condition that an appropriate printing pressure is applied to the surface 3a of the printing mask 3. 3, and the filling and scraping operation of the cream solder 7 on the surface 3 a is performed.

A pressure generating member 28 is provided near the tip of the squeegee. Further, each of the driving device 26 and the vertical driving devices 16 and 18 is connected to a control device 24 that controls the operation of the cream solder printing device 10.

FIG. 2 is a side view showing a mounting structure of a pressure generating member provided near the tip of the squeegee 12a. Since the other squeegee 12b has the same configuration, only the configuration of one squeegee 12a will be described.

The pressure generating member 28 is a rod having a circular cross section, and is fixed in parallel with the squeegee 12a near the tip of the squeegee 12a over the longitudinal direction of the squeegee 12a by a bracket 30 and bolts and nuts 32. When the squeegee 12 a contacts the printing mask 3, the pressure generating member 28 forms a narrow path 34 with a slight gap S between the squeegee 12 a and the printing mask 3. The gap S of the narrow path 34 is preferably about 1 mm to 3 mm.

Further, the pressure generating member 28 is
A flow path 36 of the gap T which is a flow path of the cream solder 7 to be rolled is formed between the flow path 36 and the a. The gap 36 of the flow path T is preferably about 1 mm to 3 mm. As shown in FIG. 3, the rolling cream solder 7 flows on both upper and lower sides of the pressure generating member 28, and in particular, the cream solder 7 on the lower side of the pressure generating member 28 is a narrow path 3 between the printing mask 3.
After passing through No. 4, it circulates through the flow path 36 between the squeegee 12a and the pressure generating member 28 as shown by the arrow. The height H2 of the pressure generating member 28 from the surface 3a of the printing mask 3 is lower than the rolling height H1 of the cream solder 7 during printing, and the pressure generating member 28 is buried in the cream solder during rolling during printing. are doing. The pressure generating member 28 is fixed so as not to rotate.

When the pressure generating member 28 is made of a round bar, the diameter d of the round bar is preferably 2 to 10 mm, particularly 5 to 7 mm.
Is preferred.

The squeegee 12 is formed by forming a narrow path 34 between the pressure generating member 28 and the printing mask 3.
a, 12b, the narrow path 34 during rolling.
Is higher than before. As a result, the cream solder is properly filled in the opening 4 of the printing mask 3, and the insufficient filling caused by the insufficient pressure of the cream solder 7 as in the related art is eliminated.

If the pressure generating member 28 is bent when a high pressure is generated in the narrow path 34, a uniform pressure cannot be obtained in the longitudinal direction. Therefore, the pressure generating member 28 is formed of a highly rigid material which does not bend. Is preferably performed. For example, the pressure generating member 28 is formed of metal, ceramic, or hard plastic.

FIG. 4 is a graph showing a result of measuring a change in filling pressure during a high-speed squeegee operation at a squeegee speed of 200 mm / sec. A is a characteristic of the squeegees 12a and 12b provided with the pressure generating member 28. And B are characteristics of a conventional squeegee having no pressure generating member. FIG.
As shown in (2), the pressure sensor 51 is arranged on the back surface of the printing mask 3, an opening is provided in the printing mask at a corresponding position, and the filling pressure when the squeegee is moved at a moving speed of 200 mm / sec is measured. Was. The time t on the horizontal axis is the time for the squeegee to pass over the pressure sensor, and the filling pressure P is the pressure detected by the pressure sensor via the cream solder when the squeegee passes over the pressure sensor.

As can be seen from this graph, in the squeegees 12a and 12b provided with the pressure generating member 28, even if the squeegee speed is increased, a pressure higher than a pressure required for filling (for example, Pf in the figure) is generated for a long time. However, in the conventional squeegee, when the squeegee speed is increased, a pressure equal to or higher than the required pressure Pf required for filling occurs only for a short time.

Therefore, even if the squeegee speed is increased by the squeegees 12a and 12b having the pressure generating member 28, the cream solder 7 can be sufficiently inserted into the opening 5 of the printing mask 3.
Is filled.

As described above, the pressure generating member 2 made of a round bar
In the case of 8, the cross-sectional shape of the narrow path 34 is such that the introduction portion is substantially wedge-shaped, and the pressure can be increased while inviting the cream solder 7.

The narrow path 34 may have a wedge-shaped cross section as shown in FIGS. 5 and 6 for the same purpose. FIG.
The pressure generating member 28 is a rod having a semicircular cross section, and the pressure generating member 28 forms a narrow passage 34 having a wedge cross section. FIG. 6 shows a configuration in which the pressure generating member 28 is formed into a wedge-shaped cross-section while leaving a diameter surface of a rod having a semi-circular cross-section, and the pressure-generating member 28 forms a narrow path 34 having a wedge-shaped cross-section. is there.

The pressure generating member 28 and the printing mask 3
The cross-sectional shape of the narrow path 34 is not particularly limited, and only a narrow gap may be formed between the narrow path 34 and the printing mask by the pressure generating member.

The narrow path 34 preferably has a gap of about 1 mm to 3 mm between itself and the printing mask 3 as described above.
It is sufficient that a gap of about 10 mm is formed between the two.

The shape of the pressure generating member 28 is not particularly limited. The pressure generating member 28 is provided in addition to the round bar, as shown in FIG.
The cross section shown in FIG.
The rod may have a wedge-shaped cross section as shown in FIG. As shown in FIGS. 5 and 6, when the surface 28a of the pressure generating member 28 facing the printing mask 3 is an inclined surface in order to form a narrow path 34 having a wedge-shaped cross section, The angle is preferably about 30 degrees. Even if the shape of the pressure generating member 28 is changed as described above, the filling pressure generally has the characteristic indicated by A in FIG. 4, and the required pressure required for filling is longer than in the conventional case.

It is preferable that the pressure generating member 28 has a built-in heating element 38 as shown in FIG. The pressure generating member 28 having the built-in heating element 38 appropriately heats the cream solder 7 to maintain the temperature of the cream solder 7 at a constant level, thereby making the cream solder 7
Is maintained constant, and stable filling characteristics are obtained.

FIG. 8 shows a cream solder printing operation using the cream solder printing apparatus 10 configured as described above.
This will be described below with reference to FIG. In step (indicated by "S" in the figure) 1, the following operation is performed.
First, a predetermined amount of cream solder 7 is supplied to the surface 3a of the printing mask 3. In the case of printing in the right direction, the printed board 5 is positioned on the printing mask 3 so as to overlap with the printing mask 3, and the squeegee 12a for printing in the right direction is lowered by the vertical drive device 16.
At this time, the tip portion 20 of the squeegee 12a is brought into contact with the surface 3a of the printing mask 3 with an appropriate printing pressure.

In step 2, while keeping this state, the base plate 14 is moved rightward by the driving device 26, and the squeegee 12a is linearly moved rightward in the printing direction. Thus, in step 3, filling and scraping of the cream solder 7 into the opening 4 of the printing mask 3 by the squeegee 12a is started. At this time, the rolling cream solder 7 flows on the upper and lower sides of the pressure generating member 28, and in particular, the cream solder 7 on the lower side of the pressure generating member 28 passes through the narrow path 34 between the printing mask 3 and the lower side. , Squeegee 12a
Circulates through a flow path 36 between the pressure generating member 28 and the pressure generating member 28. When the cream solder 7 passes through the narrow path 34, the filling pressure is increased as compared with the conventional case, and the opening 4 is sufficiently filled with the cream solder 7 even when the squeegee speed is increased.

In step 4, the squeegee 12a that has reached the movement end position stops moving. After this, step 5
The cream solder 7 is printed by separating the printed circuit board 5 from the printing mask 3 at. Next, in the leftward printing, similarly to the above-described rightward printing, after the printed circuit board 5 is positioned on the printing mask 3 and superimposed, the vertical driving device 18 causes the leftward printing squeegee 1 to move.
2b is lowered. Also at this time, the tip of the squeegee 12b is brought into contact with the surface 3a of the printing mask 3 with an appropriate printing pressure. Subsequent operations are performed in the same manner as in the above-described rightward printing. By alternately repeating the printing operation as described above, the land 6 of the printed circuit board 5 is
The cream solder 7 is continuously printed and applied thereon.

Since the cream solder printing apparatus 10 of the above embodiment is of a type that moves in both the left and right printing directions, it has both the squeegees 12a and 12b, but only one of the cream solder printing apparatuses is used. The squeegee 12a or 12b corresponding to the moving direction may be provided.

In the above embodiment, each squeegee is moved up and down. However, as shown in FIG. 9, both squeegees may not move up and down during printing and may always contact the printing mask surface. The printing apparatus shown in FIG. 9 performs the filling and scraping operations of the cream solder while the pair of squeegees are always in contact with the printing mask during printing, and reduces the printing pressure applied when the movement of the squeegee ends. Release and release the printed circuit board from the printing mask. Printing is continuously performed by repeating this operation. By doing so, the cream solder is always held between the two squeegees, and the vertical movement of each squeegee can be omitted, so that the printing time can be further reduced. When printing is completed, both squeegees are raised by the driving means and held at the standby position. The configuration of the printing apparatus shown in FIG. 9 is different from that of the printing apparatus shown in FIG. 1 in the operation control, but the configuration is the same, so that the description of the configuration is omitted.
A side plate 50 is provided on one or both of the squeegees 12a and 12b, and can prevent the cream solder 7 from moving to a position off the squeegees 12a and 12b. Furthermore, although the squeegees 12a and 12b are configured to be driven by independent vertical drive devices, both squeegees may be attached to one vertical drive device.

[0058]

Next, embodiments of the present invention will be described. The squeegee speed in each of the following embodiments is 200 mm / sec, which is higher than the conventional squeegee speed (40 mm / sec).

Example 1 In order to observe the change of the filling pressure due to the presence or absence of the pressure generating member and the change of the squeegee angle, the present invention provided with a conventional squeegee having no pressure generating member and a pressure generating member made of a round bar. With the squeegee of the embodiment, the squeegee angle α
Was printed at 60 degrees. The squeegee used was made of urethane rubber.

Sample a (Example): With pressure generating member Sample b (Comparative Example): Without pressure generating member In Sample a, a round bar having a diameter of 5 mm was used as a pressure generating member. Gap is 3mm,
The gap between the pressure generating member and the squeegee was set to 1 mm.
The results are shown in FIG.

As is clear from the graph shown in FIG.
As in the case of the sample a, the presence of the pressure generating member could maintain the high pressure state for a long time. Therefore, it can be seen that good printing can be performed even when the squeegee speed is increased. In contrast,
As in the case of the sample b, a sufficient pressure could not be obtained without the pressure generating member. This indicates that the pressure generating member is extremely effective.

Example 2 The printing state was observed by changing the cross-sectional shape of the pressure generating member. Other printing conditions are almost the same as in the first embodiment. Sample e: a circular cross section having a diameter d of 5 mm Sample f: a semicircular cross section having a diameter d of 5 mm, and an angle θ with the printing mask of 30 degrees (FIG. 5) Sample g: a semicircular cross section having a diameter d of 8 mm, for printing The angle θ with the mask is 30 degrees (FIG. 5). Sample h: A semicircle having a diameter d of 8 mm is processed into a wedge-shaped cross section with an angle β of 30 degrees while leaving the diameter surface, and the angle θ with the printing mask
30 ° (FIG. 6) Sample i: Circular cross section having a diameter d of 6 mm Sample j: Circular cross section having a diameter d of 7 mm Sample k: No pressure generating member (comparative example) The results are shown in FIG.

As can be seen from the results shown in FIG. 11, the presence of the pressure generating members such as samples e to j could maintain the high pressure state for a long time as compared with the prior art. However, it can be seen that good printing can be performed, and the pressure generating member is extremely effective. Further, in the case of the samples e, i, and j using the round bars having the diameters d of 5 mm, 6 mm, and 7 mm as the pressure generating members, there is no need to perform complicated machining on the material in connection with the production of the pressure generating members. Since the pressure generating member can be provided with a simple configuration, the pressure generating member can be provided without increasing the manufacturing cost, which is more effective.

FIG. 11 shows that the cross-sectional shape of any of the pressure generating members can be maintained at a higher pressure for a longer time than in the prior art. The shape is not limited to the cross section, and any shape may be used as long as a narrow path is formed between the pressure generating member and the printing mask.

[0065]

According to the present invention, a pressure generating member that forms a narrow path between the squeegee and a printing mask during printing and that forms a flow path with the squeegee is provided near the tip of the squeegee. As a result, the cream solder rolling during the movement of the squeegee passes through the narrow path, so that a higher pressure is generated in the narrow path than before. Therefore, even if the squeegee speed is increased, the cream solder is sufficiently filled in the opening when the pressure generating member faces the opening of the printing mask, and the filling is not insufficient.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a cream solder printing apparatus according to an embodiment of the present invention.

FIG. 2 is a mounting configuration diagram of a pressure generating member.

FIG. 3 is a diagram illustrating a rolling state of cream solder.

FIG. 4 is a graph showing characteristics of a filling pressure by a squeegee with and without a pressure generating member.

FIG. 5 is a diagram illustrating a modified example of a pressure generating member and a narrow path.

FIG. 6 is a diagram illustrating another modified example of the pressure generating member and the narrow path.

FIG. 7 is a diagram illustrating another modified example of the pressure generating member.

FIG. 8 is a flowchart showing an operation of the cream solder printing apparatus shown in FIG.

FIG. 9 is a configuration diagram of a cream solder printing apparatus according to another embodiment of the present invention.

FIG. 10 is a graph showing the results of Example 1.

FIG. 11 is a graph showing the results of Example 2.

FIG. 12 is a configuration diagram of a conventional cream solder printing apparatus.

13 is a diagram illustrating a state in which printing is performed by the squeegee illustrated in FIG. 11;

FIG. 14 is a view showing a state in which cream solder is being filled into an opening by the squeegee shown in FIG. 11;

FIG. 15 is a diagram illustrating a case where an unfilled portion of cream solder occurs in an opening of a printing mask.

FIG. 16 is a graph showing a change in filling pressure according to a squeegee passage time by a conventional device.

[Explanation of symbols]

 Reference Signs List 3 printing mask 4 opening 5 circuit board 6 land 7 cream solder 8 solder resist 10 cream solder printing device 12a, 12b squeegee 14 base plate 16, 18 vertical drive device 20 standby position 22 operating position 24 control device 26 drive device 28 pressure Generating member 30 Bracket 32 Bolt / nut 34 Narrow path 36 Flow path 38 Heating element

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Naoichi Kaku 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Inventor Satoshi Takahashi 1006 Kazama Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (72) Inventor Toshiyuki Murakami 1006 Kazuma Kadoma, Kazuma, Osaka Matsushita Electric Industrial Co., Ltd.F-term (reference)

Claims (8)

[Claims] 1. A squeegee moves in a printing direction on a surface of a printing mask in which an opening is formed, so that cream solder supplied on the surface is transferred to a circuit board surface located on a back surface of the printing mask. In a cream solder printing apparatus for printing and applying through the opening, a narrow path is formed between the printing mask and the printing mask at the time of printing, and a pressure generating member that forms a flow path between the printing mask and the squeegee is provided. A cream solder printing device provided over the vicinity of the tip of a squeegee. 2. The cream solder printing apparatus according to claim 1, wherein said pressure generating member is a round bar. 3. The cream solder printing apparatus according to claim 1, wherein the pressure generating member has a built-in heating element. 4. The cream solder application apparatus according to claim 1, wherein a pair of the squeegees are provided, and the squeegee is always in contact with the printing mask at least during printing. 5. The cream solder printing apparatus according to claim 1, wherein the narrow path has a wedge-shaped cross section that narrows toward the squeegee. 6. A height of the pressure generating member from the surface of the printing mask is lower than a rolling height of the cream solder at the time of printing, and the pressure generating member is buried in the cream solder during the rolling during printing. The cream solder printing apparatus according to any one of claims 1 to 5, wherein: 7. The cream solder printing apparatus according to claim 1, wherein the pressure generating member is fixed so as not to rotate. 8. A squeegee moves in the printing direction on the surface of the printing mask having the opening formed thereon, so that the cream solder on the surface is placed on the circuit board surface located on the back surface of the printing mask. In a cream solder printing method of printing and applying via a squeegee, printing and applying while increasing the pressure of the cream solder flowing between the print mask and a pressure generating member provided near the tip of the squeegee. Cream solder printing method.