JPS60127135A - Hot press - Google Patents

Abstract

PURPOSE:To mold an adhered object of which dimension fluctuation is few and having no residual air bubble by a method wherein the heating and pressurizing is carried out using a heating plate so that the ramification loss of distribution pipes and the passage loss in the heating plate are made the same, and uniform surface temperature distribution can be obtained in the heating and cooling processes. CONSTITUTION:Steam and cooling water enter in a distribution chamber 19 of a header 21 through a water supply inlet 22, and are supplied uniformly to a heating and cooling passage 24 in the heating plate. Steam and cooling water which have been exchanged in the passage 24 are discharged from a drain outlet 23 through an assembling chamber 20 of the header 21. Namely, the section forms of the distribution chamber 19 and the assembling chamber 20 of the header 21 are made such that the ramification loss and the confluence loss are made constant, the uniform flow distribution to the steam and cooling water passages 24 of the heat plates 16, 17, 18 is made possible, and on the heat plate surface separated further from the passages, the temperature becomes the mean value of the going and returning passages, and the temperature distribution can be maintained uniform while heating and cooling of the adhered object.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a hot paste suitable for bonding multilayer printed wiring boards of various electronic devices such as computers.

[Background of the invention]

In recent years, in order to realize high-density mounting of components onto a molded object such as a printed wiring board, there has been a trend toward multilayering a plurality of printed wiring boards.

Conventionally, in a hot press that heats and presses a plurality of printed wiring boards in multiple layers, as shown in FIG. is mounted on the cellar, and a lower heating plate 6 is fixed to the lower heat insulating plate 5' on top of the F polster 4, and an intermediate heating plate 7 is installed on the upper part provided with an opening for carrying in and out of the adhered material.
is supported by a counter cylinder 8, and at the top, an upper heating plate 9 is thermally insulated by an upper heat insulating plate 10, and is fixed to an upper bolster 12 connected to the lower press frame 1 by a column 11.

In this hot press, a bonded object 13 such as a multilayer printed wiring board is inserted between a lower hot plate 6 and an intermediate hot plate 7, and between an intermediate hot plate 7 and an upper hot plate 9, and the hot plates 6 and 7 are heated. At the same time, the cooling control device 14 applies molding heat energy, and at the same time, the hydraulic device 15 supplies hydraulic pressure to the main ram cylinder 2 and the calanter cylinder 8, and the object to be adhered 13 is pressurized and bonded. In order to uniformly heat or cool the hot plate, the steam and cooling water passages in plates 6, 7, and 9 are connected to the center surface of the hot plate so as to connect the inlets and outlets at the ends of the hot plate, as shown in Figures 2 and 3. Parallel or series passages run through.

However, in the passage shown in FIG. 2, although the amount of steam and cooling water flows uniformly through each passage, since the passage is long, a temperature difference occurs due to the difference in the amount of heat absorbed at the inlet and outlet. Therefore, during constant temperature control with a small amount of heat absorbed, a uniform temperature distribution on the surface of the hot plate can be obtained, but during heating and cooling processes with a large amount of heat absorbed, there is a difference in the temperature of the second side of the hot plate near sunrise and one inch near the exit. growing. On the other hand, in the passage shown in Figure 3, the length from the inlet to the outlet is shortened, but the distribution of steam and cooling water in the parallel passages is not uniform, resulting in variations in the amount of steam and cooling water. 0 As described above, variations in temperature distribution during heating and cooling processes occur because the softening, melting, and hardening times of the pre-preg adhesive differ depending on the bonded area, resulting in the generation of residual air bubbles (voids) and the risk of damage to the multilayer printed board. There is a problem in that the variation in dimensional changes becomes large and the reliability decreases.

[Purpose of the invention]

In view of the above points, the present invention has developed a hot press that can mold adherends with little dimensional change and no residual bubbles by heating and pressing with a hot plate that provides a uniform surface temperature distribution even during heating and cooling processes. The purpose is to provide.

[Summary of the invention]

It is thought that it is necessary to manufacture highly accurate hot presses to mold objects to be bonded such as multilayer printed wiring boards due to precision, and so mechanical measures to improve precision have been pursued. However, experimental results show that mechanical It has become clear that a multilayer printed wiring board with little dimensional change and no residual air bubbles will not be obtained unless measures are taken to improve accuracy and temperature distribution is improved in all steps of the bonding process. As a measure to obtain a uniform temperature distribution, the present invention makes the flow rate in each passage in the hot plate uniform, equalizes the branching loss of the distribution pipe and the passage loss in the hot plate, and reduces the heating and cooling medium. In order to reduce the temperature difference from the hot plate inlet to the outlet, the distance from the distribution pipe to the collecting pipe was made as short as possible, and the hot plate was designed with passages that could cancel out the temperature difference. Features.

[Embodiments of the invention]

FIG. 4 shows an embodiment of the hot press of the present invention.

This will be explained with reference to FIGS. 5 and 6.

In FIGS. 4, 5, and 6, the same reference numerals as in FIG. 1 indicate the same parts.

Reference numeral 16 indicates a lower heating plate fixed on the lower heat insulating plate 5, an intermediate heating plate 17 having an opening for carrying in and out of adherends at the upper part is supported by a counter cylinder 8, and an upper heating plate 18 is at the top. It has a structure that is thermally insulated by an upper heat insulating plate 10, and these heat plates 16, 17 and 18 are connected to a header 21 consisting of a distribution chamber 19 and a gathering chamber 20, as shown in FIG.
It is composed of a water supply port 22, a drain port 23, and a steam and cooling water passage 24.

In FIG. 5, steam and cooling water enter the distribution chamber 19 of the header 21 through the water supply port 22, and are supplied to each heating and cooling passage 24 in the hot plate with equal flow distribution. The steam and cooling water heat-exchanged in the passage 24 pass through the gathering chamber 20 of the header 21 and are discharged from the drain port 23.

According to this embodiment, since the cross-sectional shape of the distribution chamber 19 and gathering chamber 20 of the header 21 has a constant branching and confluence loss, the flow rate is uniform to the steam and cooling water passages 24 of the hot plates 16, 17 and 18. In addition, since the passage 24 is connected to the distribution chamber 19 every round trip, the temperature of the heat medium changes due to heat exchange in the middle of the passage, and the amount of heat exchange changes near the passage, but the heat away from the passage changes. On the plate surface, the value is the average value for the outward and return passes, and a uniform temperature distribution can be obtained on the hot plate surface even during the temperature rising or cooling process.

Figure 6 shows another embodiment of the hot press of the present invention, in which a uniform flow rate is distributed without providing a distribution or gathering chamber, and one in which the amount of heat exchanged is changed due to a temperature change of the heating medium in the middle of the passage. One round trip that cancels out is arranged above and below.

〔Effect of the invention〕

According to the hot press of the present invention, the temperature distribution during heating and cooling of the adherend can be made uniform, so it is possible to mold the adherend with little dimensional change and no residual bubbles.

Therefore, when the object to be adhered is used, for example, in the work of adhering multilayer printed wiring boards, a great effect is exhibited.

[Brief explanation of the drawing]

FIG. 1 shows the structure of a conventional hot press; the front view shows the structure of the hot press of the present invention; FIGS.
The figure is a three-dimensional view of the hot plate. 1...F frame, 2...ram cylinder, 3...
・Ram, 4...Lower bolster-15...Lower insulation board, 6
...Lower hot plate, 7...Middle hot plate, 9...Upper hot plate, 1
0...Top insulation board, 12...Top bolster-114...
- Heating/cooling device, 15... Hydraulic device, 16... Lower hot plate, 17... Intermediate hot plate, 18... Upper hot plate, 19...
- Distribution room, 20...Collection room, 24...Heating medium passage. Agent Patent Attorney Akio Takahashi No. 1 Figure □□□] 'fJ z Solid fJ3 Figure'! ; 4 Figure\J 5 Figure 4

Claims (1)

[Scope of Claims] 1. A hot press comprising a ram cylinder, upper and lower bolsters, a hot plate, etc., characterized in that steam and cooling water passages are provided in the hot plate. 2. The hot press according to claim 1, wherein the steam and cooling water passages in the hot plate are a plurality of reciprocating passages formed by a set of distribution/collection pipes. 3. The hot press according to claim 1, wherein a plurality of the steam and cooling water passages in the hot plate are connected to branch pipes, each of which is reciprocated in sets of upper and lower parts.