Hot press

• US 5,182,121 A
• Filed: 10/09/1990
• Issued: 01/26/1993
• Est. Priority Date: 10/11/1989
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd., Hitachi Techno Engineering Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi, Ltd., Hitachi Techno Engineering Company Limited (Hitachi, Ltd.)
• Inventors: Fujii, Mutsumasa, Torii, Keiichiro, Kubosawa, Minoru, Kawaguchi, Masami, Kyooi, Masayuki, Murooka, Hideyasu, Miyashita, Akimi, Kogawa, Kiyonori, Ooki, Nobuaki
• Primary Examiner(s): Woo, Jay H.
• Assistant Examiner(s): Bushey, Scott
• Application Number:
  US07/594,711
• Time in Patent Office: 840 Days
• Field of Search: 100/90, 100/93 R, 100/93 P, 100/194, 156/286, 156/382, 156/583.1, 425/405.1, 425/406, 425/407, 425/338, 425/504, 425/508, 425/509, 425/518, 425/520, 425/DIG. 47, 425/DIG. 60
• US Class Current: 425/338
• CPC Class Codes: B29C 2043/561 under vacuum conditions
• CPC Class Codes: B29C 33/04 using liquids, gas or steam tyre moulds with incorporated heating or cooling means using liquids, gas or steam B29D30/0601
• CPC Class Codes: B29C 43/32 Component parts, details or accessories; Auxiliary operations
• CPC Class Codes: B29C 43/56 Compression moulding under special conditions, e.g. vacuum
• CPC Class Codes: B30B 15/0017 Deairing means
• CPC Class Codes: B30B 15/064 with heating or cooling means
• CPC Class Codes: H05K 3/4611 by laminating two or more circuit boards H05K3/4652 takes precedence

Abstract

A hot press including a displaceable sleeve for surrounding materials of a multi-layer substrate under a reduced pressure condition, a gas pressurizing condition and a heating condition with thermal plates. Upper and lower sealing units seal an interior of the sleeve, with a mechanism lowering and raising the sleeve. A pilot check mechanism prevents a lower bolster from raising/lowering upon the reduced pressure condition and the gas pressure condition, and a retainer maintains the lowered or raised condition of the sleeve. The multi-layer substrate is formed under the reduced pressure condition and the gas pressure condition. Accordingly, the atmosphere and moisture between the materials of the multi-layer substrate and volatile composition are removed. Additionally, a void generated during the heat and pressure process by the heating plates is eliminated from the multi-layer substrate. By carrying out the formation of the multi-layer substrate at the heat and pressure by the heating plates under the gas pressure condition, a final dimensional precision and shape are enhanced and a warpage or twist is suppressed.

Claims

1. A hot press for mutually aligning materials of a multi-layer substrate of printed circuit boards and adhesive resin and interposing the materials into the heating plates and effecting heating and pressurization to form the multi-layer substrate, the hot press comprising:

a base frame;

a lower bolster movable up and down by a ram of a hydraulic cylinder supported by said base frame;

a column fixed to said base frame for guiding the up and down movement of the lower bolster;

an upper bolster fixed to an upper end portion of said column and confronting said lower bolster;

upper and lower heating plates respectively fixed through insulative plates to said upper and lower bolsters;

an intermediate heating plate located between said upper and lower heating plates and supported by said upper bolster;

heating means for supplying a thermal medium to said intermediate heating plate, said upper heating plate and said lower heating plate and collecting the thermal medium from the heating plate;

hydraulic pressure means for supplying pressurized oil to said hydraulic cylinder;

a sleeve movable up and down along a side surface of said upper bolster by moving means, said sleeve being adapted to surround said materials for the multi-layer substrate with a lower end portion of said sleeve being in contact with an upper surface of said lower bolster;

first sealing means for sealing an interior of said sleeve when said sleeve is in contact with the upper surface of said lower bolster;

second sealing means for sealing an interior of said sleeve;

discharging means for discharging atmosphere contained in said sleeve maintained under a sealed condition by said first and second sealing means;

means for supplying a gas maintained at a predetermined pressure into said sleeve; and

a hydraulic means including a pilot check mechanism for preventing said lower bolster from being raised due to a differential pressure between the upper surface and lower surface of said lower bolster when the interior of said sleeve is maintained at one of a vacuum pressure condition and a high pressure condition due to the predetermined gas pressure.

2. A hot press for mutually aligning materials of a multi-layer substrate of printed circuit boards and adhesive resin and interposing the materials into heating plates and effecting heating and pressurization to form the multi-layer substrate, the hot press comprising:

a base frame;

a lower bolster movable up and down by a ram of a hydraulic cylinder supported by said base frame;

a column fixed to said base frame for guiding the up and down movement of the lower bolster;

an upper bolster fixed to an upper end of said column and confronting said lower bolster;

upper and lower heating plates respectively fixed through insulative plates to said upper and lower bolsters;

an intermediate heating plate supported by said upper bolster by suspension rods;

heating means for supplying a thermal medium to said intermediate heating plate, said upper heating plate and said lower heating plate and collecting the thermal medium from the heating plate;

a passage for the thermal medium for at least one of cooling and heating said intermediate plate formed in said suspension rods;

hydraulic pressure means for supplying pressurized oil to said hydraulic cylinder;

a sleeve movable up and down along a side surface of said upper bolster by moving means, said sleeve being adapted to surround said materials for the multi-layer substrate with a lower end portion of said sleeve being in contact with an upper surface of said lower bolster;

first sealing means for sealing an interior of said sleeve when said sleeve is in contact with the upper surface of said lower bolster;

second sealing means for sealing an interior of said sleeve;

discharging means for discharging atmosphere contained in said sleeve maintained under a sealed condition by said first and second sealing means and;

means for supplying a gas maintained at a predetermined pressure into said sleeve.