JPWO2010024220A1 - Press machine - Google Patents

Abstract

There is provided a press device that hot-presses a workpiece between hot plates and then cold-presses the workpiece by cooling the hot plate while pressing the workpiece. This press apparatus includes a heating medium circulation path through which a heating medium that exchanges heat with the heating board circulates through the heating board, a pump that circulates the heating medium in the heating medium circulation path, and a heating unit that heats the heating medium. A heat storage means for exchanging heat between the first branch path branched from the heat medium circulation path and returned to the heat medium circulation path, and the heat medium passing through the branch path. A second branch path that branches from the heat medium circulation path and returns to the heat medium circulation path; a cooling means that is provided in the second branch path and that cools the heat medium that passes through the branch path; Detected by first temperature detecting means for detecting the temperature of the heat medium or hot platen in the circulation path, second temperature detecting means for detecting the temperature of the heat storage means, and first and second temperature detecting means. A circulation path control means for controlling the flow of the heat medium to the first and second branch paths based on the temperature; Eteiru.

Description

  The present invention relates to a press apparatus for press-forming a workpiece between hot plates.

  2. Description of the Related Art Press devices that form a product such as a printed wiring board by heating and pressing (hot pressing) a work piece formed by laminating a resin material such as a prepreg sheet and copper foil between hot plates are widely used. Yes. When a product is molded using such a pressing device, the product is cooled while being pressed between hot plates so that the product is not warped or distorted due to thermal stress when the product is cooled after hot pressing. Press is performed.

  An apparatus that performs both hot pressing and cold pressing using the same hot platen is proposed in Japanese Patent Application Laid-Open No. 2002-153999 (Japanese Patent Publication). The press device described in Japanese Patent Application Laid-Open No. 2002-153999 circulates a heat medium with a pump or the like in a heat medium circulation passage passing through the inside of the hot plate, and controls the temperature of the heat medium with a heater or a cooler. Both heating and cooling of the panel can be performed.

  In a press apparatus that alternately performs hot press and cold press using the same hot platen as described above, the heater for heating the hot platen from room temperature to the forming temperature every time press forming is performed. Therefore, the power consumption of the heater is high. In other words, since the heat supplied from the heater during hot pressing is discharged outside the system during cold pressing, a huge amount of waste heat is generated each time a product is molded, and the use efficiency of thermal energy is high. That wasn't true.

  This invention is made | formed in view of said situation, and it aims at providing the press apparatus with high utilization efficiency of a thermal energy.

  According to an embodiment of the present invention, there is provided a press apparatus that continuously performs hot press and cold press by changing the temperature of a hot plate while pressurizing a workpiece between the hot plates. This press apparatus is partially configured from a flow path formed in a heating plate, a heating medium circulation path through which a heating medium for adjusting the temperature of the heating plate circulates, and a heating medium in the heating medium circulation path. A pump that circulates the heat medium, a heating means that heats the heat medium, a first branch path that branches from the heat medium circulation path and returns to the heat medium circulation path, and is provided in the first branch path. A heat storage means for exchanging heat with the passing heat medium, a second branch path branched from the heat medium circulation path and returning to the heat medium circulation path, and a branch path provided in the second branch path. A cooling means for cooling the heat medium passing through the heat medium, a first temperature detecting means for detecting the temperature of the heat medium or the hot platen in the heat medium circulation path, and a second temperature detecting means for detecting the temperature of the heat storage means , Based on the temperature detected by the first and second temperature detecting means, to the first and second branch paths And a circulation path control means for controlling the flow of medium. The circulation path control means causes the heat medium to flow through the first branch path when the cold press is started and accumulates heat in the heat storage means, and then when the hot press is started, the heat medium is supplied to the first branch path. The flow of the heat medium is controlled so that the heat medium is heated by the heat accumulated in the heat storage means.

  According to the above embodiment, the hot platen is cooled by storing a part of the heat supplied to the hot plate during the hot press process in the heat storage means during the cold press, and the next workpiece is hot pressed. At that time, it is possible to send the heat stored in the heat storage means to the hot platen to heat the hot platen. For this reason, the amount of waste heat in one molding is smaller than the amount of heat necessary for molding the product by the amount of heat stored in the heat storage material. In addition, since the heat generation amount of the heating means is suppressed by the heat storage amount of the heat storage material, a pressing device with a small energy consumption of the heating means is realized.

  In the above embodiment, when the temperature of the heat medium is lowered for the cold press, the circulation path control means causes the heat medium to flow to the second branch path after flowing the heat medium to the first branch path. It is preferably configured to control the flow of the heat medium. Further, when the circulation path control means determines that the temperature of the heat medium or the heating plate in the heat medium circulation path and the temperature of the heat storage means are close to an equilibrium state, the heat medium is divided into the first heat medium branch. It is preferable to be configured to control the flow of the heating medium so as not to flow in the path. Further, the circulation path control means does not operate the heating means when raising the temperature of the heat medium for hot pressing and is flowing through the first branch path, and heats the first branch path. It is preferable that the heating means is operated when the medium is not flowing. In addition, the circulation path control means, when performing heat transfer between the heat medium and the heat storage means, allows the heat medium to flow through the first branch path so that all of the heat medium circulating in the heat medium circulation path flows through the first branch path. It is preferably configured to control the flow.

  If the circulation path control means is configured as described above, the thermal energy accumulated in the heat storage means can be used effectively.

  The press device of the above embodiment further includes a first flow rate adjustment valve provided in the heat storage means in the first branch path, and the circulation path control means controls the opening degree of the first flow rate adjustment valve. It is preferable that the temperature of the heat storage means can be controlled by adjusting the flow rate of the heat medium flowing through the first branch path. Furthermore, the circulation path control means controls the opening degree of the first flow rate adjustment valve so that a part of the heat medium flows through the first branch path while the temperature of the hot platen is maintained at the molding temperature. It is preferable to adopt a configuration to do so.

  If the circulation path control means is configured in this way, the time from the start of hot pressing until the temperature of the hot platen reaches the molding temperature is shortened, and more products can be manufactured in a short time.

  The press device of the above embodiment further includes a third branch path that branches from the heat medium circulation path on the upstream side of the hot platen and goes to the cooling means, and a second flow rate adjustment valve provided in the third branch path. You may have. In this case, it is preferable that the circulation path control means is configured to adjust the flow rate of the heat medium toward the cooling means, bypassing the hot platen, by controlling the opening of the second flow rate adjustment valve. Furthermore, the circulation path control means controls the opening degree of the second flow rate adjusting valve so that the temperature of the hot platen is maintained at the molding temperature of the workpiece during hot pressing, and the temperature of the hot platen is normal temperature during cold pressing. It is preferable to be configured to control the opening of the second flow regulating valve so as to be maintained.

  If the circulation path control means is configured in this way, the hot platen can be accurately maintained at a constant temperature.

  Further, the circulation path control means completely closes the second flow rate adjustment valve until the temperature of the heating medium or the heating plate in the heating medium circulation path reaches the molding temperature of the workpiece during hot pressing, and during cold pressing, It is preferable that the flow rate adjusting valve is completely closed until the temperature of the heating medium or the heating plate in the heating medium circulation path reaches room temperature.

  If the circulation path control means is configured in this way, the temperature of the hot platen can be rapidly changed to reach the molding temperature or normal temperature quickly.

  In one embodiment of the present invention, the heating means is a heater built in the heating platen.

  In this case, since the heating means is accommodated in the hot platen, it is not necessary to separately secure a space for installing the heating means, and a compact and simple press device is realized.

  In another embodiment of the present invention, the heating means is a heater capable of heating the heat medium outside the hot platen.

  In this case, restrictions on the type and size of the heater to be used are alleviated, the heater options are expanded, and it becomes possible to select a heater more suitable in terms of performance and cost.

  In one embodiment of the present invention, the heat storage means may have a heat storage plate formed of a material containing at least one of copper, aluminum, and iron.

  If a sensible heat type heat exchanger having such a simple configuration is employed as the heat storage means, an inexpensive heat storage means with good thermal characteristics can be realized. In this case, it is preferable that the heat storage plate is covered with a heat insulating material. The heat dissipation suppresses the divergence of the heat accumulated in the heat storage plate, further improving the energy utilization efficiency.

It is a figure which shows schematic structure of the press apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows schematic structure of the thermal storage means used in embodiment of this invention. It is II 'sectional drawing of FIG. 2A. It is a flowchart of the process in the basic example of 1st Embodiment of this invention. It is a graph which shows the temperature change of a heat disc and a thermal storage means in the basic example of 1st Embodiment of this invention, and the press processing of 2nd Embodiment. It is a figure which shows the thermal storage path | route Rs in the basic example of 1st Embodiment of this invention. It is a figure which shows the circulation path Ro in the basic example of 1st Embodiment of this invention. It is a figure which shows the cooling path | route Rc in the basic example of 1st Embodiment of this invention. It is a figure which shows the circulation path Ro in the modification 1 of 1st Embodiment of this invention. It is a flowchart of the process in the modification 1 of 1st Embodiment of this invention. It is a graph which shows the temperature change of a hot platen and a thermal storage means in the press process of the modification 1 and the modification 2 of 1st Embodiment of this invention. It is a figure which shows the circulation path Ro in the modification 2 of 1st Embodiment of this invention. It is a flowchart of the process in the modification 2 of 1st Embodiment of this invention. It is a figure which shows schematic structure of the press apparatus which concerns on 2nd Embodiment of this invention. It is a flowchart of the process in 2nd Embodiment of this invention. It is a figure which shows the thermal storage path | route Rs' in 2nd Embodiment of this invention. It is a figure which shows the circulation path Ro 'in 2nd Embodiment of this invention. It is a figure which shows the cooling path | route Rc 'in 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a schematic configuration of a press apparatus 101 according to the first embodiment (basic example) of the present invention. The press device 101 forms a product such as a printed wiring board by heating and pressing (hot pressing) a workpiece S in which a resin material such as a prepreg sheet and a copper foil are laminated between flat platen hot plates. It is a press device. As shown in FIG. 1, the press apparatus 101 has three flat platen hot plates (an upper hot platen 123, an intermediate hot platen 124, and a lower hot platen 125) arranged one above the other. On the lower surface of the upper heating platen 123, the upper and lower surfaces of the intermediate heating platen 124, and the upper surface of the lower heating platen 125, press surfaces for pressing the workpiece S are formed. The workpiece S is disposed between the opposing press surfaces of two adjacent hot plates, and the workpiece S is hot-pressed between the heated hot plates to be formed into a product. In the present embodiment, since the intermediate heating platen 124 has one stage, the number of workpieces S that can be pressed simultaneously is two. However, in another embodiment, two or more intermediate heating plates 124 are provided between the upper heating plate 123 and the lower heating plate 125 so that three or more workpieces S can be simultaneously press-formed. Also good.

  The upper heating platen 123 is fixed to the lower surface of the crown surface plate 121 and the lower heating platen 125 is fixed to the upper surface of the table surface plate 122 via a heat insulating material 126, respectively. The table surface plate 122 is driven in the vertical direction by a driving means (not shown) such as a hydraulic cylinder. The intermediate heat platen 124 is supported by the lower heat platen 125 from below and can move up and down. When the table surface plate 122 is raised (driven in a direction approaching the crown surface plate 121), the workpiece S is pressed between the hot plates.

  The workpiece S includes a resin material such as a prepreg sheet, and the processing temperature of the resin material (a temperature in a predetermined range higher than the curing start temperature if the resin material is a thermosetting resin, for example, glass if it is a thermoplastic resin) It is press-molded at a predetermined range higher than the transition temperature (hot pressing step). Further, the workpiece S is kept pressed between the hot plates at room temperature so that the workpiece S is not warped due to thermal stress until the hot workpiece S after hot pressing is cooled to room temperature. It is cooled to near (cold press process). In order to perform this processing, the press apparatus 101 according to the first embodiment of the present invention can control the temperature of the hot plates 123, 124, and 125 between a high temperature at which the hot pressing process is performed and a temperature close to normal temperature. It has become.

  Next, the temperature control mechanism of the hot plates 123, 124, 125 will be described. In the first embodiment of the present invention, in order to suppress temperature unevenness (non-uniform temperature distribution on the press surface) of the hot platen, there is a flow path through which a liquid heat medium such as silicone oil flows inside each hot platen. It is stretched around. For this reason, the heat medium removes heat from the high temperature portion and supplies the deprived heat to the low temperature portion, thereby suppressing temperature unevenness of the hot platen. A heater H for heating the heat medium is disposed in the flow path formed in each heating platen. In the first embodiment, a cartridge heater is used as the heater H. An example of a heating plate incorporating such a cartridge heater is disclosed in Japanese Patent Application Laid-Open No. 2002-153999.

  Here, a mechanism for circulating the heat medium in the heat medium circulation channel will be described. The heat medium circulates in the heat medium circulation channel by the pressure supplied from the pump unit 131. A part of the heat medium circulation flow path is branched into a plurality of flow paths, and each of the branched flow paths passes through the corresponding hot platen, and then joins again and returns to the pump unit 131. A branch block 141 is provided between the pump outlet 131o of the pump unit 131 and each of the heating plates 123, 124, 125 for branching the heat medium circulation passage. Further, a junction block 142 is provided between each of the heating plates 123, 124, 125 and the pump inlet 131i of the pump unit 131 to rejoin the branched heat medium circulation passages. Both ends of the flow path formed inside each heat platen 123, 124, 125 are opened to the outside of the heat plate as heat medium inlets 123i, 124i, 125i and heat medium outlets 123o, 124o, 125o, respectively. As shown in FIG. 1, the heat medium inlets 123i, 124i, and 125i of each heat plate are connected to each of a plurality of heat medium outlets 141o provided in the branch block 141 by flexible hoses. Similarly, the heat medium outlets 123o, 124o, and 125o of each heating plate are connected to each of a plurality of heat medium inlets 142i provided in the junction block 142 by flexible hoses. Further, the pump outlet 131o of the pump unit 131 is connected to the heat medium inlet 141i of the branch block 141, and the heat medium outlet 142o of the junction block 142 is connected to the pump inlet 131i of the pump unit 131 via stainless steel pipes, which will be described later. Connected by etc. That is, the heat medium sent out from the pump outlet 131o of the pump unit 131 is branched into a plurality of (three in the present embodiment) flow in the branch block 141, and then passes through the respective hot plates 123, 124, 125, After being merged into one flow path again by the merge block 142, it is returned to the pump inlet 131 i of the pump unit 131.

In the basic example of the first embodiment of the present invention, the heat medium outlet 142o of the confluence block 142 is connected to the inlet 151i of the three-way switching valve 151. Way valve 151 is a valve capable of switching to deliver a heating medium to be introduced from the inlet 151i from first outlet 151o ₁ and one of the second outlet 151o _2. The second outlet 151o ₂ is connected to a heat storage branch flow path 166 that returns to the pump unit 131 via a heat storage means 132 described later. The first outlet 151 o ₁ is connected to a heat medium circulation passage that returns to the pump unit 131 without passing through the heat storage means 132. That is, whether or not the heat medium is passed through the heat storage means 132 can be controlled by the three-way switching valve 151.

A first branch 161 is provided between the first outlet 151o ₁ of the three-way switching valve 151 and the pump inlet 131i. From the 1st branch part 161, the branch flow path 162 for cooling which returns to the pump unit 131 via the cooler 133 for cooling a heat medium is branched. The heat medium flowing through the cooling branch flow path 162 passes through the cooler 133 from the heat medium inlet 133 i to the heat medium outlet 133 o, and then joins the heat medium circulation flow path at the first merging portion 163. A first stop valve 152 and a second stop valve 154 are provided immediately after the first branch portion 161 in the cooling branch passage 162 and the heat medium circulation passage, respectively. That is, whether or not the heat medium is passed through the cooler 133 can be controlled by the first stop valve 152 and the second stop valve 154.

  In addition, a second branch portion 164 is provided between the pump outlet 131o of the heat medium circulation passage and the branch block 141. From the second branch part 164, a temperature adjusting branch channel 165 that branches toward the heat medium inlet 133 i of the cooler 133 is branched. A diaphragm valve 153 is disposed in the middle of the temperature adjustment branch flow path 165 so that the flow rate of the heat medium flowing through the temperature adjustment branch flow path 165 can be adjusted. When the diaphragm valve 153 is opened as much as possible, a part of the heat medium sent from the pump outlet 131o is diverted to the temperature adjusting branch flow path 165 at the second branch portion 164, cooled by the cooler 133, and again pump 131. Return to. Therefore, by adjusting the opening degree of the diaphragm valve 153, it is possible to finely adjust the temperature of the heat medium supplied to the hot plates 123, 124, and 125.

Here, a case where the heat medium introduced from the inlet 151i of three-way valve is a three-way changeover valve 151 as fed into the heat medium circulation channel is switched from the first outlet 151o _1. At this time, the diaphragm valve 153 in a state of being fully closed, opening the first stop valve 152, and closes the second stop valve 154, all the heat transfer medium for cooling delivered from the first outlet 151o ₁ of three-way valve Since it passes through the cooler 133 via the branch flow path 162, the heat medium is rapidly cooled. Further, since the diaphragm valve 153 is fully closed, all of the low-temperature heat medium sent out by the pump unit 131 is supplied to the hot plates 123, 124, and 125, and the hot plate is rapidly cooled. On the other hand, in the state where the first stop valve 152 is closed and the second stop valve 154 is opened, the heat medium exiting from the first outlet 151o ₁ of the three-way switching valve 151 does not pass through the cooler 133, and therefore the temperature hardly decreases. Return to the pump 131. As described above, the first stop valve 152 and the second stop valve 154 are used when switching whether to perform rapid cooling of the hot platen.

Further, a second junction 167 is provided between the second stop valve 154 and the first junction 163 in the heat medium circulation channel. In the second junction section 167, a second outlet 151o ₂ heat storage branch passage 166 branched from the three-way valve 151 is merged into the heating medium circulation channel. Heat storage means 132 is provided in the middle of the heat storage branch flow path 166, and heat can be transferred between the heat medium flowing through the heat storage branch flow path 166 and the heat storage means 132.

  Here, the structure of the heat storage means 132 will be described with reference to FIGS. 2A and 2B. The heat storage means 132 of the first embodiment of the present invention is a plate-like member in which a meandering heat medium flow path is formed. FIG. 2A is a schematic cross-sectional view of the heat storage means 132 cut along the surface on which the flow path is formed. 2B is a schematic cross-sectional view taken along the line II ′ in FIG. 2A. 2A and 2B, the heat storage means 132 has a structure in which a heat storage plate 1322 made of aluminum is covered with a heat insulating layer 1324 of urethane foam, and is further surrounded by a stainless protection plate 1326. . A meandering heat medium flow path 1320 is formed in the heat storage plate 1322. Short pipes for connecting to the heat storage branch flow path 166 are attached to the openings at both ends of the heat medium flow path 1320, which serve as an inlet 132 i and an outlet 132 o, respectively. The heat storage means 132 of the first embodiment of the present invention configured as described above is a sensible heat type heat storage means excellent in economy and workability.

  In addition, the structure of the heat storage means 132 is not limited to the thing of said 1st Embodiment. For example, a metal material with high thermal conductivity and specific heat is suitable for the material of the heat storage plate 1322, and for example, copper, aluminum, copper alloy, or aluminum alloy may be used. Stainless steel may be used. In addition, although the heat storage plate 1322 of the first embodiment has one meandering heat medium flow path 1320, a plurality of parallel heat medium flow paths 1320 may be formed. In this case, both ends of the plurality of heat medium flow paths 1320 are configured to branch / join at the inside or outside of the heat storage plate 1322. In this case, the heat medium flow path 1320 may be formed in a straight line without meandering. Further, instead of the metal plate, for example, a thick metal block (for example, a columnar or prismatic metal block) in which a tube is formed at the center may be used. In addition, sensible heat storage means formed from other solid materials (ceramics, etc.) or liquid materials (water, silicone oil, etc.) with high thermal conductivity and specific heat, or latent heat type that stores heat by latent heat during phase change Other forms of heat storage means, such as a combination of a sensible heat type heat storage means and a latent heat type heat exchange means, may be used. Alternatively, a thermos structure may be introduced into the heat storage means by replacing part or all of the heat insulating material with a vacuum space or by evacuating the space filled with the heat insulating material. Moreover, it is good also as a structure which connected the some of the thermal storage means 132 shown by FIG. 2 in series or in parallel.

  A temperature sensor 112 is provided on the hot plates 123, 124 and 125. Similarly, the heat storage means 132 is provided with a temperature sensor 114. The controller 110 controls the three-way switching valve 151, the first stop valve 152, the second stop valve 154, and the diaphragm valve 153 based on the temperatures detected by these temperature sensors 112 and 114, and controls the temperature of the hot platen. Is going.

  A procedure for pressing the workpiece S in the press apparatus 101 having the above configuration will be described below. FIG. 3 is a flowchart showing a press processing procedure in the basic example of the first embodiment of the present invention. In the following description and drawings, the step of press processing is abbreviated as “S”. FIG. 4 is a graph showing temporal changes in the temperature of the hot platen and the heat storage means 132 when the workpiece S is pressed. The horizontal axis of the graph in FIG. 4 indicates time (T), and the vertical axis indicates temperature (t). In FIG. 4, the temperature of the hot platen (that is, the temperature detected by the temperature sensor 112) is indicated by a solid line, and the temperature of the heat storage means 132 (that is, the temperature detected by the temperature sensor 114) is indicated by a broken line. .

As shown in FIG. 4, in the initial state (T ₁ ), the temperature of the hot platen is normal temperature t _L , while the temperature of the heat storage means 132 is a temperature t close to the molding temperature t _H of the workpiece S. _{It is 1} . Further, in the initial state, the heater H inside the hot plates 123, 124, 125 is not operating. When hot pressing is started from this initial state, each valve is set so that the heat medium circulates in a circulation path Rs (hereinafter referred to as “heat storage path Rs”) passing through the heat storage means 132 as shown by a thick line in FIG. Is controlled (FIG. 3: S101). Specifically, the controller 110 controls the three-way valve to flow the heating medium from the inlet 151i to the second outlet 151o _2, closing the first stop valve 152, further the diaphragm valve 153 is fully closed. At this time, all the heat medium circulates through the heat storage branch channel 166. As shown in FIG. 4, the temperature of the heating plate in the initial state is a normal temperature t _L, the temperature of the heat medium flowing through the heat medium circulation channel is also temperature near room temperature t _L. Then, the temperature of the heat storage means 132 for than the room temperature is sufficiently high temperatures t _1, heat is transferred from the heat storage means 132 to the heat medium, the temperature of the heating medium is increased. Then, the heat medium heats the heating plate 123, 124, and 125, the temperature of the heating plates is also increased from _{t L} to _{t 2} as shown in FIG. On the other hand, the temperature of the heat storage means 132 decreases from t ₁ to t ₂ because heat is taken away by the heat medium.

  When the hot plates 123, 124, 125 reach a temperature suitable for applying a pressing pressure to the workpiece S, the table surface plate 122 is raised to press the workpiece between the hot plates (FIG. 3). : S102, S103).

When the movement of heat from the heat storage means 132 to the heat medium continues, the temperature of the temperature and the heat storage means 132 of the heating plate 123, 124, 125 approaches the temperature _{t 2,} most heat transfer to the heat medium from the heat storage means 132 It becomes a state close to no equilibrium state (FIG. 4: T ₂ ). From the detection results of the temperature sensor 112 provided in the hot plates 123, 124, and 125 and the temperature sensor 114 provided in the heat storage means 132, the controller 110 determines that the temperature of the heat plate and the heat storage means is close to an equilibrium state. Then, the controller 110 turns on the heater H built in the heating plates 123, 124, and 125 (FIG. 3: S104, S105), and causes the heat medium to circulate through the circulation path Ro indicated by a thick line in FIG. Each valve is controlled (FIG. 3: S106). Specifically, the controller 110 controls the three-way switching valve so that the heat medium flows from the inlet 151 i to the first outlet 151 o ₁ and opens the second stop valve 154. At this time, the first stop valve 152 and the diaphragm valve 153 remain closed. In this state, since the heating medium does not pass through the device that actively takes heat away from the heating medium, the heating medium heated by the heater H heats the heating plate, and the heating plate temperature rises as shown in FIG. to continue. On the other hand, since no heat medium flows through the heat storage means 132, the temperature of the heat storage means 132 hardly changes. For example, the controller 110 determines whether the temperature difference between the heat storage means 132 and the heat plate is within a predetermined value (for example, 5 ° C.) or the temperature rise rate of the heat plate or the temperature decrease rate of the heat storage means 132 is a predetermined threshold value. When the temperature is lower than, it is determined that the temperature of the heating plate and the heat storage means is close to an equilibrium state.

When the temperature of the hot platen reaches the molding temperature t _H (FIG. 4: T ₃ ), the controller 110 adjusts the temperature of the part of the heat medium flowing through the circulation path Ro as indicated by a thick dashed line in FIG. The flow is diverted to the temperature adjustment path Rt passing through the cooler 133 through the branch flow path 165 (FIG. 3: S107, S108). Specifically, controller 110, in order to maintain the temperature of each heating platen in the molding temperature t _H, based on the temperature of the heating plates detected by the temperature sensor 112, adjusting the degree of opening of the diaphragm valve 153 Thus, the amount of the heat medium flowing through the temperature adjustment path Rt is adjusted.

After the workpiece S is heated at the molding temperature t _H for a certain time (FIG. 4: T ₄ ), the controller 110 reduces the temperature of the hot plates 123, 124, and 125 while pressing the workpiece S to cold Start pressing. At the start of the cold press, the controller 110 first turns off the heater H built in the hot plates 123, 124, 125 (FIG. 3: S110). Next, the controller 110 switches the path through which the heat medium circulates again to the heat storage path Rs shown in FIG. 5 (FIG. 3: S111). Specifically, the controller 110 controls the three-way valve to flow the heating medium from the inlet 151i to the second outlet 151o _2, further diaphragm valve 153 is fully closed. At this time, the first stop valve 152 remains closed. At this time, all the heat medium circulates via the heat storage branch channel 166. As shown in FIG. 4, when the cold press is started, the temperature of the heat storage means 132 is a temperature t ₂ lower than the temperature t _{H of the} hot platen, so that the heat moves from the heat medium to the heat storage means 132, The temperature of the heating medium drops. Then, since the low-temperature heat medium cools the hot plates 123, 124, and 125, the temperature of each hot plate also falls from t _H to t ₁ as shown in FIG. On the other hand, the temperature of the heat storage means 132, because it is heated by the heat medium, it rises toward the _{t 2} to _{t 1.}

Further followed by heat transfer to the heat storage means 132 from the heating medium, the temperature and the temperature of the heat storage means 132 of the heating plate 123, 124, 125 approaches the temperature _{t 1,} the heat transfer from the heat medium to the heat storage means 132 It becomes a state close to an almost equilibrium state (FIG. 4: T ₅ ). When the controller 110 determines that the temperature of the hot platen and the temperature of the heat storage means are close to an equilibrium state, the controller 110 controls each valve so that the heat medium circulates in the cooling path Rc indicated by a bold line in FIG. FIG. 3: S112, S113). Specifically, the controller 110 detects the temperature of the hot platen and the temperature of the heat storage unit from the detection results of the temperature sensor 112 provided in the hot plates 123, 124, and 125 and the temperature sensor 114 provided in the heat storage unit 132. When it is determined that a state close to equilibrium, the heating medium from the inlet 151i to the first outlet 151o ₁ controls the three-way valve to flow. Further, the controller 110 opens the first stop valve 152 and closes the second stop valve 154. At this time, the diaphragm valve 153 remains closed. In this state, all of the heat medium is directed to the cooler 133 through the cooling branch flow path 162, so that the heat medium is rapidly cooled. Further, since the diaphragm valve 153 is fully closed, all the low-temperature heat medium sent out by the pump unit 131 is sent to the hot plates 123, 124, and 125, and the hot plate is rapidly cooled. On the other hand, since no heat medium flows through the heat storage means 132, the temperature of the heat storage means 132 hardly changes. Note that the controller 110, for example, when the temperature difference between the heat storage means 132 and the heating plate falls within a predetermined value (for example, 5 ° C.), or the temperature decrease rate of the heating plate or the temperature increase rate of the heat storage means 132 has a predetermined threshold value. When the temperature falls below, it is determined that the temperature of the hot platen and the heat storage means is close to an equilibrium state.

Then, the controller 110 detects that the temperature of the heating plate becomes room temperature t _L (Figure 4: T _6), switch to the circulation path Ro heat medium again is shown the path that circulates in Figure 6, heat A part of the medium is diverted to the temperature adjustment path Rt (FIG. 3: S115). Specifically, the controller 110 controls the three-way valve so that flow the heating medium from the inlet 151i to the first outlet 151o _1, closing the first stop valve 152, opens the second stop valve 154. Then, by adjusting the degree of opening of the diaphragm valve 153 based on the temperature change of the heating plate, to maintain the temperature of the heating plates in a substantially normal temperature t _L. Then, after pressing for a certain period of time at room temperature t _L (FIG. 4: T ₇ ), the table surface plate 122 is lowered to take out the workpiece S for which the cold pressing has been completed (FIG. 3: S 116, S 117).

  In the basic example of the first embodiment of the present invention described above, the control of the three-way switching valve 151, the first stop valve 152, the second stop valve 154, and the diaphragm valve 153 is controlled based on the temperature of the heat plate and the heat storage means 132. Is going. However, the present invention is not limited to the above configuration, and the temperature of the heat medium in the heat medium circulation channel (for example, the temperature of the heat medium circulation channel in the heat plate or the heat medium in the pump 131) and heat storage. The above-described valves 151, 152, 153, and 154 may be controlled based on the temperature of the means 132.

Further, in the basic example of the first embodiment of the present invention described above, the heat storage means 132 is provided while the temperature of the hot platen is maintained at the molding temperature t _H (between T _{3 and} T ₄ in FIG. 4). The heat medium does not flow. However, the present invention is not limited to the above configuration. In two modifications of the first embodiment described below, the heat storage means 132 can be heated by flowing a part of the heat medium through the heat storage means 132 during hot pressing. The configuration of the press device in the following modification 1 is the same as the basic example of the first embodiment except that a three-way diaphragm valve 151 ′ is provided instead of the three-way switching valve 151. Detailed description is omitted.

Figure 8 is a diagram showing the circulation path Ro to maintain in the modified example 1 of the first embodiment of the present invention, the temperature of the heating platen in the molding temperature t _H. As shown in FIG. 8, the press device 101 ′ according to the first modification is provided with a three-way diaphragm valve 151 ′ instead of the three-way switching valve 151. The three-way diaphragm valve 151 ′ stores heat via the inlet 151 i ′ connected to the heat medium outlet 142 o of the junction block 142, the first outlet 151 o ₁ ′ connected to the first branch part 161, and the heat storage branch channel 166. It has a second outlet 151 o ₂ ′ connected to the means 132. The three-way diaphragm valve 151 ′ is a valve capable of adjusting the ratio of the flow rate of the heat medium flowing from the first outlet 151o ₁ ′ to the flow rate of the heat medium flowing from the second outlet 151o ₂ ′. The flow rate ratio is controlled by the controller 110.

FIG. 9 is a flowchart showing the procedure of the press process by the press apparatus 101 ′ of the first modification. FIG. 10 is a graph showing the time change of the temperature of the hot platen and the heat storage means 132 when the workpiece S is pressed. In the first modification, when the temperature of the hot platen reaches the molding temperature t _H (FIG. 10: T ₃ ′), the controller 110 indicates a part of the heat medium flowing through the circulation path Ro with a thick dashed line in FIG. The flow is diverted to the temperature adjustment route Rt passing through the cooler 133 through the temperature adjustment branching channel 165 shown in FIG. 9 (FIG. 9: S107, S108 ′). Specifically, controller 110, in order to maintain the temperature of each heating platen in the molding temperature t _H, based on the temperature of the heating plates detected by the temperature sensor 112, adjusting the degree of opening of the diaphragm valve 153 Thus, the amount of the heat medium flowing through the temperature adjustment path Rt is adjusted.

Furthermore, the controller 110 adjusts the ratio between the flow rate of the heat medium flowing from the first outlet 151o ₁ ′ of the three-way diaphragm valve 151 ′ and the flow rate of the heat medium flowing from the second outlet 151o ₂ ′, and flows through the circulation path Ro. A part of the heat medium is divided into the heat storage means temperature adjustment path Rt ₁ passing through the heat storage branch flow path 166 shown by a thick two-dot chain line in FIG. 8, and the heat storage means 132 is heated by the divided heat medium ( FIG. 9: S108 ′). As a result, while the temperature of each hot platen is maintained at the molding temperature t _H (FIG. 10: T ₃ ′ to T ₄ ′), the temperature of the heat storage means 132 gradually increases from t _2a ′ to t _2b ′. Then, at the hot press end time T ₄ ′, the temperature reaches a temperature higher than the temperature t ₂ in the basic example of the first embodiment. Therefore, the temperature difference is small in the heat plate and the heat storage means 132 at time T _4, to quickly reach an equilibrium state. Further, the temperature of the heat storage means 132 in an equilibrium state after hot pressing (that is, the initial temperature of the heat storage means 132) t ₁ ′ is also higher than the temperature t ₁ in the basic example of the first embodiment. Therefore, the temperature t _2a ′ in the equilibrium state (time T ₂ ) before hot pressing in the next cycle is also higher than the temperature t ₂ in the basic example of the first embodiment, and the temperature of each hot platen is the initial temperature t ₁ ′. The time (T ₃ ′ −T ₂ ′) until the molding temperature t _H is reached is also shortened. Since the time required for raising and lowering the temperature of the hot platen as a whole is shortened, the time required for the press process by the press apparatus 101 ′ of the first modification (the time from T ₁ to T ₇ ) is the first time. The time required for the press process by the press apparatus 101 of the basic example of the embodiment is shorter. Therefore, according to the configuration of the first modification, more products can be manufactured in a short time. Further, since the difference between the temperature t _2a ′ in the equilibrium state before hot pressing and the molding temperature t _H becomes small, the energy consumption used for raising the temperature of the hot platen is reduced. In addition, the ratio of the heat medium to be diverted to the heat storage means temperature adjustment path Rt ₁ can be set to an arbitrary value in advance.

In addition, the temperature reached by the heat storage means 132 at time T ₄ ′ can be set. In this case, the ratio of the heat medium to be diverted to the heat storage means temperature adjustment path Rt ₁ is automatically adjusted by controlling the three-way diaphragm valve 151 ′ so that the heat storage means 132 reaches the set temperature by the time T ₄ ′.

Further, the diversion of the heat medium to the heat storage means temperature adjustment path Rt ₁ (that is, the heat storage means 132) has the effect of lowering the temperature of the heat medium similarly to the diversion of the heat medium to the temperature adjustment path Rt (ie, the cooler 133). is there. Therefore, the adjustment of the partial flow rate of the heat medium to the heat storage means temperature adjustment path Rt ₁ can also be used for the temperature adjustment of the hot platen. Although the heat removed by cooling using the cooler 133 cannot be reused, the heat removed by cooling using the heat storage means 132 can be reused. Therefore, the temperature adjustment of the hot platen using the heat storage means 132 is energy efficient. high.

As described above, in the first modification, the heat storage means 132 can be heated while the temperature of the hot platen is maintained at the molding temperature t _H by using the three-way diaphragm valve 151 ′. Modification 2 of the first embodiment of the present invention described below is an example in which the same effect as that of Modification 1 is achieved by another configuration.

Figure 11 is a diagram showing the circulation path Ro to maintain in the modified example 2 of the first embodiment of the present invention, the temperature of the heating platen in the molding temperature t _H. As shown in FIG. 11, the press device 101 ″ of the second modification has substantially the same configuration as the press device 101 of the basic example of the first embodiment, but the heat medium sent out from the merging block 142 is the same. A different point is that a bypass path 170 is provided, which bypasses the three-way switching valve 151 and flows to the heat storage means 132, and a diaphragm valve 155 is provided in the bypass path, and the diaphragm valve 155 flows through the bypass path 170. The bypass path 170 connects a branch point 168 provided at the front stage of the three-way switching valve 151 and a junction point 169 provided at the front stage of the heat storage means 132.

12 is a flowchart showing the procedure of the press process by the press device 101 ″ of the second modification. In the press process of the second modification, the temperature of the hot platen and the heat storage means varies according to the graph shown in FIG. In the second modification, when the temperature of the hot platen reaches the molding temperature t _H (FIG. 10: T ₃ ), the controller 110 converts a part of the heat medium flowing through the circulation path Ro in FIG. Then, the temperature is diverted to the temperature adjustment path Rt passing through the cooler 133 via the temperature adjustment branch flow path 165 shown in FIG. 12 and cooled (FIG. 12: S107, S108 ″). Specifically, controller 110, in order to maintain the temperature of each heating platen in the molding temperature t _H, based on the temperature of the heating plates detected by the temperature sensor 112, adjusting the degree of opening of the diaphragm valve 153 Thus, the amount of the heat medium flowing through the temperature adjustment path Rt is adjusted.

Further, the controller 110 adjusts the flow rate of the heat medium flowing through the diaphragm valve 155, so that a part of the heat medium flowing through the circulation path Ro is bypassed by the bypass path 170 and the heat storage branch indicated by a thick two-dot chain line in FIG. flowing the heat storage unit temperature adjustment paths Rt ₂ bisection through a portion of the flow passage 166 to heat the heat storage means 132 with the diverted heating medium. (Fig. 12: S108 ") heat shunted to the heat storage unit temperature adjustment paths Rt ₂ the proportion of medium is adjusted to a predetermined value by controlling the diaphragm valve 155. the ratio of the heat medium to be diverted to the heat storage unit temperature adjustment paths Rt ₂ can be set in advance any value.

In addition, the temperature reached by the heat storage means 132 at time T ₄ ′ can be set. In this case, the ratio of the heat medium to be diverted to the heat storage means temperature adjustment path Rt ₂ is automatically adjusted by controlling the diaphragm valve 155 so that the heat storage means 132 reaches the set temperature by the time T ₄ ′.

Further, the adjustment of the flow rate of the heat medium to the heat storage means temperature adjustment path Rt ₂ can be used for the temperature adjustment of the hot platen.

  In the basic example of the first embodiment of the present invention, the heating medium and the heating plate are heated by the cartridge heater H built in the heating plates 123, 124, and 125, but the present invention is limited to the above configuration. The heating medium and the hot platen may be heated by other methods. In the second embodiment of the present invention described below, the heat medium is heated by an external heater system provided outside the hot platen.

  FIG. 13 shows a schematic configuration of a press apparatus 102 according to the second embodiment of the present invention. In the press device 102 of the second embodiment, the heater H is not built in the heat medium circulation passages in the hot plates 123, 124, 125, and instead, in the heat medium circulation passage outside the heat plate. More specifically, an external heater system 134 is provided between the first branch portion 161 and the second junction portion 167. As the external heater system 134, for example, one described in Japanese Patent No. 2709565 can be applied. The external heater system 134 used in the present embodiment has a plurality of cartridge heaters H 'built in a meandering pipeline. Since the other configuration of the press device 102 is the same as that of the press device 101 (FIG. 1) of the basic example of the first embodiment, the description thereof is omitted.

  The procedure for pressing the workpiece S in the press apparatus according to the second embodiment having the above-described configuration will be described below. FIG. 14 is a flowchart showing a press processing procedure according to the second embodiment of the present invention. In the second embodiment, the temperature of the hot platen is adjusted based on the graph shown in FIG. 4 as in the basic example of the first embodiment.

As shown in FIG. 4, in the initial state (T ₁ ), the temperature of the hot platen is normal temperature t _L , while the temperature of the heat storage means 132 is a temperature t close to the molding temperature t _H of the workpiece S. _{It is 1} . In the initial state, the external heater system 134 is not operating. When starting hot pressing from this initial state, each valve is controlled so that the heat medium circulates through a heat storage path Rs ′ passing through the heat storage means 132 as shown by a thick line in FIG. 15 (FIG. 14: S201). Specifically, the controller 110 controls the three-way valve to flow the heating medium from the inlet 151i to the second outlet 151o _2, closing the first stop valve 152, further the diaphragm valve 153 is fully closed. At this time, all of the heat medium is circulated through the heat storage branch channel 166. As shown in FIG. 4, the temperature of the heating plate in the initial state is a normal temperature t _L, the temperature of the heat medium flowing through the heat medium circulation channel is also temperature near room temperature t _L. Then, the temperature of the heat storage means 132 for than the room temperature is sufficiently high temperatures t _1, heat is transferred from the heat storage means 132 to the heat medium, the temperature of the heating medium is increased. Then, since the heat from the heat medium to the heating plates 123, 124, 125 moves, the temperature of the heating plates is also increased from _{t L} to _{t 2} as shown in FIG. On the other hand, the temperature of the heat storage means 132 decreases because the heat medium is deprived of heat.

  When the hot plates 123, 124, 125 reach a temperature suitable for applying a pressing pressure to the workpiece S, the table surface plate 122 is raised to press the workpiece between the hot plates (FIG. 14). : S202, S203).

When the movement of heat from the heat storage means 132 to the heat medium continues, the temperature of the temperature and the heat storage means 132 of the heating plate 123, 124, 125 approaches the temperature _{t 2,} most heat transfer to the heat medium from the heat storage means 132 It becomes a state close to no equilibrium state (FIG. 4: T ₂ ). From the detection results of the temperature sensor 112 provided in the heat plates 123, 124, and 125 and the temperature sensor 114 provided in the heat storage means 132, the controller indicates that the temperature of the heat plate and the temperature of the heat storage means are close to an equilibrium state. When the controller 110 determines, the controller 110 starts the heat generation of the external heater system 134 (FIG. 14: S204, S205), and controls each valve so that the heat medium circulates in the circulation path Ro ′ indicated by a thick line in FIG. (FIG. 14: S206). Specifically, the controller 110 controls the three-way switching valve so that the heat medium flows from the inlet 151 i to the first outlet 151 o ₁ and opens the second stop valve 154. At this time, the first stop valve 152 and the diaphragm valve 153 remain closed. In this state, since the heat medium circulates only through the circulation path Ro ′ passing through the external heater system 134, the heat medium heated by the external heater system 134 heats the heat platen, and the heat plate temperature as shown in FIG. 4. Continues to rise. On the other hand, since no heat medium flows through the heat storage means 132, the temperature of the heat storage means 132 hardly changes. For example, the controller 110 sets a predetermined threshold value when the temperature difference between the heat storage means 132 and the heat plate falls within a predetermined value (for example, 5 ° C.), or when the temperature rise rate of the heat plate or the temperature decrease rate of the heat storage means 132 is When it falls below, it is determined that the hot platen and the heat storage means are close to an equilibrium state.

When the temperature of the hot platen reaches the molding temperature t _H (FIG. 4: T ₃ ), the controller 110 converts a part of the heat medium flowing through the circulation path Ro ′ to the temperature indicated by the dashed line in FIG. The flow is diverted to the temperature adjustment path Rt ′ passing through the cooler 133 via the adjustment branch flow path 165 (FIG. 14: S207, S208). Specifically, controller 110, in order to maintain the temperature of each heating platen in the molding temperature t _H, by adjusting the degree of opening of the diaphragm valve 153 based on the temperature of the heating plates detected by the temperature sensor 112 The amount of the heat medium flowing through the temperature adjustment path Rt ′ is adjusted.

After the workpiece S is heated for a certain time (FIG. 4: T ₄ ), the controller 110 starts cold pressing to lower the temperature of the hot plates 123, 124, and 125 while pressing the workpiece S. At the start of cold pressing, the controller 110 first stops heating by the external heater system 134 (FIG. 14: S210). Next, the controller 110 switches the path through which the heat medium circulates again to the heat storage path Rs ′ shown in FIG. 15 (FIG. 14: S211). Specifically, the controller 110 controls the three-way valve to flow the heating medium from the inlet 151i to the second outlet 151o _2, further diaphragm valve 153 is fully closed. At this time, the first stop valve 152 remains closed. Then, as shown in FIG. 15, all of the heat medium circulates through the heat storage branch channel 166. As shown in FIG. 4, since the temperature of the heat storage means 132 is a temperature t ₂ lower than the temperature t _{H of the} hot platen at the start of the cold press, the heat is transferred from the heat medium to the heat storage means 132, and the heat The temperature of the medium drops. Then, since the low-temperature heat medium cools the hot plates 123, 124, and 125, the temperature of each hot plate also falls from t _H to t ₁ as shown in FIG. On the other hand, the temperature of the heat storage means 132 rises from _{t 2} to _{t 1} to be heated by the heating medium.

Further followed by heat transfer to the heat storage means 132 from the heating medium, the temperature and the temperature of the heat storage means 132 of the heating plate 123, 124, 125 approaches the temperature _{t 1,} the heat transfer from the heat medium to the heat storage means 132 It becomes a state close to an almost equilibrium state (FIG. 4: T ₅ ). When the controller 110 determines that the state is close to the equilibrium state, the controller 110 controls each valve so that the heat medium circulates through the cooling path Rc ′ indicated by a thick line in FIG. 17 (FIG. 14: S212, S213). Specifically, from the detection results of the temperature sensor 112 provided in the heat plates 123, 124, and 125 and the temperature sensor 114 provided in the heat storage means 132, the temperature of the heat plate and the temperature of the heat storage means are close to an equilibrium state. When the controller 110 determines that the state has been reached, the three-way switching valve is controlled so that the heat medium flows from the inlet 151 i to the first outlet 151 o ₁ , the first stop valve 152 is opened, and the second stop valve 154 is closed. At this time, the diaphragm valve 153 remains closed. In this state, all of the heat medium passes through the cooler 133 via the cooling branch flow path 162, so that the heat medium is rapidly cooled. Further, since the diaphragm valve 153 is fully closed, all the low-temperature heat medium sent out by the pump unit 131 is sent to the hot plates 123, 124, and 125, and the hot plate is rapidly cooled. On the other hand, since no heat medium flows through the heat storage means 132, the temperature of the heat storage means 132 hardly changes. For example, the controller 110 determines that the temperature difference between the heat storage means 132 and the heat plate is within a predetermined value (for example, 5 ° C.), or the temperature decrease rate of the heat plate or the temperature increase rate of the heat storage means 132 is a predetermined threshold value. It is determined that the temperature of the hot platen and the temperature of the heat storage means are close to an equilibrium state.

When the controller 110 detects that the temperature of the hot platen has reached room temperature t _L (FIG. 4: T ₆ ), it switches the path through which the heat medium circulates again to the circulation path Ro ′ shown in FIG. A part of the heat medium is diverted to the temperature adjustment path Rt ′ (FIG. 14: S215). Specifically, the controller 110 controls the three-way valve so that flow the heating medium from the inlet 151i to the first outlet 151o _1, closing the first stop valve 152, opens the second stop valve 154. Then, by adjusting the degree of opening of the diaphragm valve 153 based on the temperature change of the heating plate, to maintain the temperature of the heating plates in a substantially normal temperature t _L. Then, after a certain period of time at room temperature _{t L} (Figure _{4: T} 7), and lowering the table surface plate 122, the workpiece S that has completed the cold pressing is extracted (Fig. 14: S216, S217).

  In the second embodiment of the present invention, an external heater system using an electrothermal cartridge heater H ′ is employed to heat the heat medium, but another type of electric heater or boiler is used instead of the cartridge heater. An external heater system using may be used.

  Moreover, it is good also as a structure which can heat the thermal storage means 132 by sending a part of heat medium which flows from the confluence | merging block 142 to the thermal storage means 132 similarly to the modification 1 and the modification 2 of 1st Embodiment of this invention.

The above is the description of the embodiment of the present invention. The present invention is not limited to the configuration of the embodiment described above, and various modifications can be made without departing from the gist of the present invention. For example, in each of the above embodiments, the cooler 133 is used to maintain the temperature of each hot platen at the molding temperature t _H during hot pressing, but the temperature can be adjusted using the heat storage means 132. . Such a process can be realized by, for example, a configuration in which the temperature adjusting branch flow path 165 is merged with the heat storage branch flow path 166 upstream of the heat storage means 132 instead of the cooling branch flow path 162.

According to an embodiment of the present invention, there is provided a press apparatus that continuously performs hot press and cold press by changing the temperature of a hot plate while pressurizing a workpiece between the hot plates. This press apparatus is partially configured from a flow path formed in a heating plate, a heating medium circulation path through which a heating medium for adjusting the temperature of the heating plate circulates, and a heating medium in the heating medium circulation path. A pump that circulates the heating medium, a heating means that heats the heating medium, a first branch path that branches from the heating medium circulation path and returns to the heating medium circulation path, and is provided in the first branch path. A heat storage means for exchanging heat with the heat medium passing through the branch path, a second branch path that branches from the heat medium circulation path and returns to the heat medium circulation path, and a second branch path are provided. A cooling means for cooling the heat medium passing through the second branch path, a first temperature detecting means for detecting the temperature of the heat medium or the hot platen in the heat medium circulation path, and a first temperature detecting means for detecting the temperature of the heat storage means. Based on the temperatures detected by the two temperature detecting means and the first and second temperature detecting means. And a circulation path control means for controlling the flow of heat medium to 岐経 path. The circulation path control means causes the heat medium to flow through the first branch path when the cold press is started and accumulates heat in the heat storage means, and causes the heat medium to flow through the first branch path when the hot press is started. The flow of the heat medium is controlled so that the heat medium is heated by the heat accumulated in the heat storage means.

  In the above embodiment, when the temperature of the heat medium is lowered for the cold press, the circulation path control means causes the heat medium to flow to the second branch path after flowing the heat medium to the first branch path. It is preferably configured to control the flow of the heat medium. In addition, when the circulation path control means determines that the temperature of the heat medium or the heating plate in the heat medium circulation path and the temperature of the heat storage means are close to an equilibrium state, the heat medium is changed to the first branch path. It is preferable that the flow of the heat medium is controlled so as not to flow. Further, the circulation path control means does not operate the heating means when raising the temperature of the heat medium for hot pressing and is flowing through the first branch path, and heats the first branch path. It is preferable that the heating means is operated when the medium is not flowing. In addition, the circulation path control means, when performing heat transfer between the heat medium and the heat storage means, allows the heat medium to flow through the first branch path so that all of the heat medium circulating in the heat medium circulation path flows through the first branch path. It is preferably configured to control the flow.

Claims (14)

A press device that continuously performs hot press and cold press by changing the temperature of the hot plate while pressing the work piece between the hot plates,
A heat medium circulation path in which a heat medium for adjusting the temperature of the hot plate is partially formed from a flow path formed in the hot plate;
A pump for circulating the heat medium in the heat medium circulation path;
Heating means for heating the heat medium;
A first branch path branched from the heat medium circulation path and returning to the heat medium circulation path;
Heat storage means provided in the first branch path and exchanging heat with a heat medium passing through the branch path;
A second branch path branched from the heat medium circulation path and returning to the heat medium circulation path;
A cooling means provided in the second branch path for cooling the heat medium passing through the branch path;
First temperature detecting means for detecting the temperature of the heating medium or the heating plate in the heating medium circulation path;
Second temperature detection means for detecting the temperature of the heat storage means;
Circulation path control means for controlling the flow of the heat medium to the first and second branch paths based on the temperatures detected by the first and second temperature detection means,
The circulation path control means causes the heat medium to flow through the first branch path when the cold press is started, accumulates heat in the heat storage means, and then starts the first press when the hot press is started. A press apparatus characterized by controlling the flow of the heat medium such that the heat medium flows through the branch path and the heat medium is heated by the heat accumulated in the heat storage means.   When the temperature of the heat medium is lowered for the cold press, the circulation path control unit causes the heat medium to flow through the first branch path and then flows through the second branch path. The press apparatus according to claim 1, wherein the flow of the heat medium is controlled as described above.   When the circulation path control means determines that the temperature of the heat medium or the heating plate in the heat medium circulation path and the temperature of the heat storage means are close to an equilibrium state, the heat medium is transferred to the first heat medium. The press apparatus according to claim 1 or 2, wherein the flow of the heat medium is controlled so as not to flow through the heat medium branch path.   The circulation path control means does not operate the heating means when raising the temperature of the heating medium for the hot pressing, and does not operate the heating means when the heating medium is flowing through the first branch path. The press device according to any one of claims 1 to 3, wherein the heating unit is operated when the heating medium is not flowing through the branch path.   The circulation path control means, when performing heat transfer between the heat medium and the heat storage means, causes all of the heat medium circulating in the heat medium circulation path to flow to the first branch path. The press apparatus according to any one of claims 1 to 4, wherein the flow of the heat medium is controlled. A first flow rate adjusting valve provided upstream of the heat storage means in the first branch path;
The circulation path control means controls the temperature of the heat storage means by adjusting the flow rate of the heat medium flowing through the first branch path by controlling the opening of the first flow rate adjustment valve. The press apparatus according to claim 1 or 2.   The circulation path control means adjusts the opening of the first flow rate adjustment valve so that a part of the heat medium flows through the first branch path while the temperature of the hot plate is maintained at the molding temperature. The press device according to claim 6, wherein the press device is controlled. A third branch path branched from the heat medium circulation path on the upstream side of the hot platen toward the cooling means;
A second flow rate regulating valve provided in the third branch path;
Further comprising
The said circulation path control means adjusts the flow volume of the heat medium which bypasses the said heat disc and goes to the said cooling means by controlling the opening degree of a said 2nd flow regulating valve. The press apparatus as described in any one of 7 to 7.   The circulation path control means controls the opening degree of the second flow rate adjustment valve so that the temperature of the hot platen is maintained at the molding temperature of the workpiece during the hot press, and the heat flow during the cold press. The press device according to claim 8, wherein the opening degree of the second flow rate adjustment valve is controlled so that the temperature of the panel is maintained at room temperature. The circulation path control means completely closes the flow rate adjusting valve until the temperature of the heating medium or the hot platen in the heating medium circulation path reaches the molding temperature of the workpiece during the hot pressing, 10. The press device according to claim 9, wherein the flow rate adjusting valve is completely closed during pressing until the temperature of the heating medium in the heating medium circulation path or the temperature of the heating plate reaches room temperature.   The press device according to any one of claims 1 to 10, wherein the heating means is a heater built in the heating platen.   The press apparatus according to any one of claims 1 to 11, wherein the heating unit is an external heater capable of heating the heat medium outside the hot platen.   The press apparatus according to any one of claims 1 to 12, wherein the heat storage means includes a heat storage plate formed of a material containing at least one of copper, aluminum, and iron. The press apparatus according to claim 13, wherein the heat storage plate is covered with a heat insulating material.

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