JP4382450B2 - Hot press and hot press hot plate - Google Patents

Description

  The present invention relates to a hot press that heats and pressurizes a molded object between hot plates, and particularly to a hot press that heats and pressurizes a molded object in a high temperature range.

  In general, steam or an electric heater is used for heating the hot plate of a hot press that heats and pressurizes the workpiece between the hot plates, and cooling water is used for cooling the hot plate. However, when cooling water is circulated through a pipe line in the hot plate to cool the hot plate, there is a problem that the cooling water becomes steam and the internal pressure of the hot plate increases too much. If the internal pressure of the hot plate rises too much, the cooling water will not flow any further, which slows cooling and causes temperature unevenness on the hot plate surface. Therefore, in the initial stage of cooling, compressed air is circulated in the pipe line to lower the temperature of the hot plate to some extent, and then high-pressure water is fed into the pipe line, which complicates the structure of the hot press. At the same time, the cooling time is prolonged. In recent years, there has been an increase in hot presses that heat a hot plate to a high temperature range of 300 ° C. or higher and heat the moldings. In such hot presses, the above-mentioned problems during cooling are more prominent. Met.

  In addition to the above, there is a hot press using oil as a medium for heating and cooling the hot plate. However, hot presses that use oil are inferior to those that use electric heaters in terms of the maximum heating temperature, and also use a large amount of oil. It was costly. As another hot press, a hot press using a heat pipe for heating and cooling a hot plate as in Patent Document 1 is known. However, as in Patent Document 1, a hot press that heats one end of a heat pipe and indirectly heats the hot plate via the heat pipe is compared to a hot press that directly heats the hot plate with an electric heater or the like. There was a problem of poor heating efficiency. The problem became more prominent especially at higher temperatures.

JP-A-8-150630 (Claims 1, 0013, 0014, FIG. 1)

  As described above, in the case of a hot press in which cooling water is circulated through a pipe line in the hot plate to cool the hot plate, the cooling water is vaporized in the hot plate and cooling of the hot plate is slowed and There is a problem such as occurrence of temperature unevenness, and in order to solve the problem, the structure of the cooling means has been complicated by providing a mechanism for supplying compressed air or high-pressure water. Further, the processing of the hot plate has a problem that the processing of the pipe line for refluxing the cooling water becomes complicated. Moreover, when heating a hot plate with a heat pipe like patent document 1, there existed a problem that the heating efficiency of a hot plate was bad. Accordingly, an object of the present invention is to provide a hot press that can maintain the heating efficiency of the hot plate, can have a simple structure for cooling the hot plate, and can uniformly cool the hot plate. And In particular, it is an object of the present invention to enable efficient heating and cooling in a hot press that heats and pressurizes a workpiece in a high temperature range. It is another object of the present invention to provide a hot plate having high thermal efficiency and easy processing for use in the hot press.

  A hot press for heating and pressurizing a workpiece between hot plates according to claim 1 of the present invention includes a heating means for directly heating the hot plate in the hot plate, and a heat pipe as a cooling means different from the heating means. And a metal plate in which a flow path of a cooling medium for cooling the heat pipe is formed is detachably provided on the heat plate via a heat insulating plate.

  A hot plate of a hot press for heating and pressurizing an object to be molded according to claim 2 of the present invention is provided with a heating means for directly heating the hot plate and a heat pipe as a cooling means separate from the heating means. And a metal plate in which a flow path of a cooling medium for cooling the heat pipe is formed is detachably provided on the heat plate via a heat insulating plate.

  The hot plate which heats and pressurizes the object to be molded between the hot plates according to claim 1 of the present invention and the hot plate of the hot press according to claim 2 are heating means (directly heating the hot plate). And a heat pipe as a cooling means in which a metal plate in which a cooling medium flow path for cooling is formed separately from the heating means is detachably provided on the heat plate via a heat insulating plate, Since the hot plate is cooled by the heat pipe, the hot plate can be efficiently heated and the hot plate can be cooled substantially uniformly.

  An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an overall view of a hot press according to the present invention. FIG. 2 is a sectional view of the hot plate and the cooling water jacket of the hot press according to the present invention.

  Each part of the hot press 11 will be described with reference to FIG. 1. The hot press 11 is provided with a movable plate 13 that can be moved up and down with respect to the upper plate 12. The hot plate 14 is disposed on the lower surface of the upper plate 12 and the upper surface of the movable plate 13, and an intermediate hot plate 14 is disposed therebetween. A ram 16 of a hydraulic cylinder 15 which is a pressurizing means is attached to the movable platen 13. When the ram 16 is lowered, the intermediate hot plate 14 is placed on a step plate 17 erected on both sides of the hot press 11 at a predetermined interval. As the ram 16 and the movable platen 13 are raised by driving the hydraulic cylinder 15, the hot plate 14 on the upper surface of the movable platen 13 and the intermediate hot plate 14 are raised, and the laminated molding which is a molding object between the hot plates 14. The product is heated and pressurized. In this embodiment, the hot press 11 is disposed in a vacuum chamber (not shown), and the front door of the vacuum chamber is opened and closed to carry in and carry out the laminated molded product. In the present invention, at least two hot plates 14 may be used.

  Next, the hot platen 14 of this embodiment will be described with reference to FIG. The hot plate 14 is a metallic rectangular plate having a thickness of about 40 to 120 mm. The intermediate hot plate 14 has both sides, and the hot plates 14 and 14 disposed on the upper plate 12 and the movable plate 13 have a flat pressing surface on one side. Moreover, the hot platen 14 of this embodiment is provided with a plurality of through holes 18 and 19 in parallel by a gun drill from one side to the other side. The through hole 18 is a hole having a relatively large inner diameter into which a cartridge heater 20 having a rod-like portion and heating means for directly heating the hot plate 14 is inserted. The through hole 19 is a hole having a relatively small inner diameter into which a heat pipe 22 described later is inserted. The through holes 18 and the through holes 19 are formed alternately (every other). In this embodiment, the interval between the through holes 18 and 18 or the interval between the through holes 18 and 19 is narrower at both ends than the interval at the center of the hot plate 14. This is because the heat radiating area of the both ends of the hot plate 14 is larger than that of the central portion, so that the interval between the cartridge heaters 20 is narrowed so that the heat supply amount per unit area is increased on the both ends. As a whole, the hot plate 14 is heated to a uniform temperature. The intervals between the through holes 18 and 18 or the intervals between the through holes 18 and 19 may be equalized. In this embodiment, the through holes 18 and 19 into which the cartridge heater 20 and the heat pipe 22 are inserted are formed in parallel, so that the processing of the hot plate 14 is simplified, and the heating means and the cooling means Since the pipes and the like do not have to be arranged so as to intersect each other in the hot plate 14, the thickness of the hot plate 14 can be reduced.

  A cartridge heater 20 as an electric heater is inserted into the through hole 18 of the hot plate 14. When an electric heater is used under vacuum, there is a problem of vacuum discharge, so that the cartridge heater 20 is generally used. The end 20a of the cartridge heater 20 protrudes from the one side 14a of the hot plate by a predetermined dimension, and the heating portion 20b of the cartridge heater 20 is disposed in the hot plate 14. An electric wire 21 that is energized to the cartridge heater 20 is connected to the end 20 a of the cartridge heater 20. As the heating means for directly heating the hot plate 14, in addition to the cartridge heater 20 described above, a pipe having a rod-like portion is formed in the hot plate 14 and a heat medium such as steam and hot oil is circulated. May be. When heating and pressurization are not performed under vacuum, a resistance heating method other than the cartridge heater 20 or an induction heating method may be used.

  In addition to the heating means, heat pipes 22 as cooling means for cooling the hot plate 14 indirectly using a cooling medium are inserted into the through holes 19 of the hot plate 14. The heat pipe 22 is a super heat conduction element having a rod-like portion in which a small amount of liquid is enclosed in a vacuum cylindrical container and a porous material is lined, and heat on one end side is extremely efficiently transferred to the other end side. Heat can be transferred, and its thermal conductivity is several tens to several thousand times that of copper. The diameter of the heat pipe 22 is slightly smaller than the inner diameter of the through-hole 19, and a gap between the through-hole 19 and the heat pipe 22 is filled with a heat conduction compound, and heat conduction from the heat pipe 22 to the heat plate 14 is performed. Good. An end portion 22 a of the heat pipe 22 and a non-main body portion 22 b having a predetermined length protrude from the other side 14 b of the heat plate, and the main body portion 22 c of the heat pipe 22 is disposed in the heat plate 14. And the cooling water jacket 23 is arrange | positioned so that the edge part 22a and the non-main-body part 22b of the heat pipe 22 can be cooled.

  The cooling water jacket 23 will be described. The cooling water jacket 23 is disposed on the other side 14b of the hot plate (only the hot plate 14 is shown in FIG. 1, and the cooling water jacket 23 on the front side thereof is omitted). Not listed). The cooling water jacket 23 is made of a metal plate having substantially the same thickness as the hot plate 14, and the heat pipe insertion hole 24 is coaxial with the heat pipe 22 of the hot plate 14 from one side to the other side in the metal plate portion 27. A plurality of positions are formed. The inner diameter of the heat pipe insertion hole 24 is slightly larger than the diameter of the heat pipe 22. In the cooling water jacket 23, a cooling water passage 25 is formed through the metal plate portion 27 in a direction perpendicular to the heat pipe insertion hole 24. The flow path 25 is connected inside. The end portion 22 a of the heat pipe 22 is formed so as to be positioned inside the cooling water flow path 25. Water supply pipes 26 a and 26 b are connected to the water introduction side inlet and the water discharge side outlet of the cooling water flow path 25, respectively, and the water supply pipes 26 a and 26 b are connected to the cooling water supply mechanism 31. Accordingly, the heat pipe 22 is cooled by the cooling water flowing in the cooling water flow path 25 in the vicinity of the end 22a. The non-main body portion 22 b other than the end portion 22 a of the heat pipe 22 protruding from the hot plate 14 is also introduced with cooling water into the heat pipe insertion hole 24 of the cooling water jacket 23 and the metal of the cooling water jacket 23. It cools by transferring heat from the plate part 27 via cooling water.

  A heat insulating plate 28 is attached to one side (hot plate 14 side) of the cooling water jacket 23 to prevent heat transfer from the hot plate 14 and leakage of cooling water from the heat pipe insertion hole 24. . By using the cooling water jacket 23, the cooling water is directly introduced into the hot plate 14 and the hot plate 14 is not directly cooled, so that the temperature of the cooling water does not rise rapidly. Therefore, there is no need to use high-pressure water or compressed air as in the prior art, and the hot plate 14 can be cooled uniformly and the amount of water used can be reduced. In the present invention, the heat pipe 22 and the cooling water jacket 23 constitute a cooling means. Note that the metal plate portion 27 of the cooling water jacket 23 may be made of a metal other than iron that is more excellent in heat transfer, and the metal plate portion 27 may be in direct contact with the non-main body portion 22 b of the heat pipe 22. Further, the non-main body portion 22b of the heat pipe 22 may also be exposed to the flow of cooling water in the cooling water flow path 25. Further, as the cooling medium, a medium other than the cooling water, for example, compressed air may be used. When compressed air is used as the cooling medium, the structure of the hot press 11 can be further simplified. Further, compressed air may be used in the early stage of cooling, and cooling water may be used in the later stage.

  In this embodiment, the hot plate 14 is mounted so that the cooling water jacket 23 is positioned in the direction of the door of the vacuum chamber. The cooling water jacket 23 can be removed from the hot plate 14. Therefore, maintenance and replacement of the cooling water jacket 23 and the heat pipe 22 can be easily performed. The cartridge heater 20 can be maintained and replaced from the door on the back side of the vacuum chamber. Therefore, it is not necessary to perform maintenance from the side of the hot press 11 having no opening in the vacuum chamber.

  Next, molding of a laminated molded product by the hot press 11 will be described. The laminated molded product is placed on the pressure surface on the upper surface side of the hot plate 14 other than the hot plate 14 disposed on the lower surface of the upper board 12, and the front door (not shown) is closed to make the vacuum chamber in a vacuum state. Then, a signal is sent from the control mechanism 29 to the hydraulic mechanism 30 that operates the hydraulic cylinder 15 to raise the movable platen 13 together with the ram 16. At the same time as the laminated molded product is pressurized between the hot plates 14, the control mechanism 29 energizes the cartridge heaters 20 of the hot plates 14 to heat the hot plates 14, and the laminated molded products are heated and heated. Pressed. Due to the heating by the cartridge heater 20, the heating plate 14 rises to a predetermined temperature (400 ° C. in the present embodiment) in a predetermined time, and thereafter is maintained at the temperature by PID control. During heating, the inside of the cooling water jacket 23 is kept in a state where there is no cooling water. The amount of heat radiated from the heat pipe 22 to the cooling water jacket 23 is equivalent to that radiated from iron or the like and does not cause a large loss.

  When the predetermined time has elapsed, the energization to the cartridge heater 20 is stopped, the heating of the hot plate 14 is finished, and then the hot plate 14 is cooled. The cooling of the hot plate 14 is sent from the control mechanism 29 to the cooling water supply mechanism 31, and the cooling water is supplied from the cooling water supply mechanism 31 to the cooling water jacket 23 through the water supply pipe 26 a. Then, the end 22a of the heat pipe 22 and the non-main body 22b side are cooled by the cooling water supplied to the cooling water jacket 23, and the cooled heat is transferred to the main body 22c on one side of the heat pipe 22. The entire hot plate 14 is cooled via the heat pipe 22. At that time, the cooling by the heat pipe 22 does not generate steam in the hot plate 14 and the hot plate 14 does not partially increase in pressure, so that the temperature of the hot plate 14 can be lowered uniformly. Then, the cooling water discharged from the cooling water jacket 23 is circulated to the cooling water supply mechanism 31 through the water supply pipe 26b, and the temperature of the cooling water is adjusted in the cooling water supply mechanism 31 and retransmitted. The method for adjusting the cooling rate includes the control of the temperature of the cooling water by the cooling water supply mechanism 31, the amount of water supplied per hour, and the position of the protrusion of the end 22a of the heat pipe 22 with respect to the cooling water passage 25 of the cooling water jacket 23 This is done by adjustment. When a predetermined time elapses or the hot plate 14 is lowered to a predetermined temperature, the movable platen 13 is lowered together with the ram 16. During molding or after molding, the vacuum state in the vacuum chamber is set to atmospheric pressure, and the molded laminated product is removed.

  In this embodiment, the example in which the hot plate 14 is heated to 400 ° C. has been described, but the temperature at which the hot plate 14 is heated is not limited to the above. However, in the example in which the hot plate 14 is heated to a high temperature region of 300 ° C. or higher, it is necessary to improve the efficiency of the heating described above, and the effect of generation of steam when the inside of the hot plate 14 is cooled by cooling water. Therefore, if the cooling is performed by the heat pipe 22 from a state heated to 300 ° C. or higher, the effect is remarkable.

  The present invention is not enumerated one by one, but is not limited to the above-described embodiment, and it goes without saying that the present invention can be applied to those modified by a person skilled in the art based on the gist of the present invention.

1 is an overall view of a hot press according to the present invention. It is sectional drawing of the hot platen and cooling water jacket of the hot press of this invention.

DESCRIPTION OF SYMBOLS 11 Hot press 12 Upper board 13 Movable board 14 Hot plate 14a One side of hot plate 14b The other side of hot plate 15 Hydraulic cylinder 16 Ram 17 Step plate 18, 19 Through-hole 20 Cartridge heater 20a, 22a End 21 Electric wire 22 Heat pipe 22b Non-main body part 22c Main body part 23 Cooling water jacket 24 Heat pipe insertion hole 25 Cooling water flow path 26a, 26b Water supply pipe 27 Metal plate part 28 Heat insulating plate 29 Control mechanism 30 Hydraulic mechanism 31 Cooling water supply mechanism

Claims (2)

In a hot press that heats and presses a workpiece between hot plates,
The heating plate includes heating means for directly heating the heating plate;
A heat pipe as a cooling means different from the heating means is disposed,
A hot press, wherein a metal plate having a cooling medium flow path for cooling the heat pipe formed therein is detachably provided on the hot plate via a heat insulating plate. In the hot press hot plate that heats and presses the workpiece,
Heating means for directly heating the hot plate;
A heat pipe as a cooling means different from the heating means is disposed,
A hot plate for a hot press, wherein a metal plate in which a flow path for a cooling medium for cooling the heat pipe is formed is detachably provided on a hot plate via a heat insulating plate.

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