Insert and mold cooling structure using the same

Abstract

To provide a reusable and maintainable core having a cooling circuit and a mold cooling structure using the same.SOLUTION: A movable inner core 180 faces a cavity 101 formed in a mold 100, and a cooling circuit 181 filled with a cooling medium and having a heat pipe function is disposed inside the movable inner core 180. A plurality of communication parts 182 that communicate with the outside of the movable inner core 180 are disposed in the cooling circuit 181. A sealing member 190 is disposed in each communication part 182, and the cooling circuit 181 is closed.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an insert used for injection molding of synthetic resin and the like, and a mold cooling structure using the same.

Background Art

[0002] As a mold cooling structure using a heat pipe as a cooling circuit, there is one described in Patent Document 1.

[0003] According to this, a heat pipe is embedded inside a movable side insert that can move forward and backward in the direction perpendicular to the parting line, and is attached to a temperature control block provided on the outside of the movable side template. A temperature control pipe is formed in the temperature control block, through which a heat medium circulates. In addition, the ejector plate pushed by the ejector rod is provided with temperature control block ejection pins, and when the ejector plate is pushed, the temperature control block and the movable side insert are pushed together to eject the optical element formed in the cavity.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the heat pipe used in the above mold cooling structure and the like is manufactured by injecting a cooling medium into the interior of a hollow tube with one end sealed, discharging the air remaining inside the hollow tube, and then sealing the other end of the hollow tube.

[0006] When the heat pipe is inspected and found to have defects and is desired to be reused, or when maintenance of the heat pipe is desired, the sealed portion at the end of the heat pipe will be damaged to open it, so there is a problem that reuse and maintenance cannot be performed.

[0007] In view of the above, the present invention aims to provide a reusable and maintainable insert having a cooling circuit and a mold cooling structure using the same. [Means for solving the problem]

[0008] The invention described in claim 1 is an insert facing a cavity formed in a mold, A cooling circuit, which has a heat pipe function and is sealed inside the aforementioned insert, The cooling circuit is provided with multiple communication sections that communicate with the outside of the insert. Each of the aforementioned communication sections is fitted with a sealing member, thereby closing the cooling circuit.

[0009] According to this, it is possible to create an insert with a cooling circuit that is reusable and maintainable.

[0010] Furthermore, the sealing member and the insert are made of metal. The sealing member seals the communication portion via a packing made of a metal that is softer and more malleable than the sealing member and the insert.

[0011] According to this, the packing deforms to create a seal, and it can also handle temperature environments where existing rubber O-rings cannot provide a seal, thus contributing to keeping the cooling circuit closed.

[0012] Furthermore, a cooling member is provided in at least the portion of the insert where the sealing member is located and in its vicinity.

[0013] According to this, the applicant has found that in testing of the insert according to the present invention, the sealing member heats up first. By placing a cooling member in the part that heats up first, the cooling effect can be improved.

[0014] Furthermore, the cooling circuit is equipped with a flow restricting unit that restricts the flow direction of the cooling medium.

[0015] According to this, it is possible to prevent the cooling medium from stopping circulating.

[0016] In the invention of claim 5, there is provided a mold cooling structure comprising the insert according to any one of claims 1, 2, 3 or 4, which faces a cavity formed in the mold, the mold cooling structure being characterized by: The mold is formed with an insert arrangement portion in which the insert is disposed, and the insert is arranged in the insert arrangement portion.

[0017] According to this, a mold cooling structure that achieves the effects of the above insert can be obtained. [Brief Description of the Drawings]

[0018] [Figure 1] It is a schematic explanatory view of a mold cooling structure in one embodiment of the present invention. [Figure 2] It is a perspective view of the insert of the same embodiment. [Figure 3] It is a longitudinal sectional view of the insert of the same embodiment. [Figure 4] It is an enlarged view of the vicinity of the communication portion in Figure 3. [Figure 5] It is a perspective view showing a state where a Peltier element is attached. [Figure 6] It is an explanatory view of the manufacturing process of the insert. [Mode for Carrying Out the Invention]

[0019] Hereinafter, one embodiment of the present invention will be described based on the drawings. A case where the present invention is applied to a mold in injection molding of synthetic resin will be described. In Figure 1, on the paper surface, the left side is defined as left, the right side as right, the upper side as top, the lower side as bottom, the near side as front, and the far side as rear.

[0020] As shown in Figure 1, the mold 100 includes a fixed mold 110 and a movable mold 150.

[0021] The fixed type 110 comprises a fixed main type 120, a fixed insert 130, and a fixed middle insert 140. The movable type 150 comprises a movable main type 160, a movable insert 170, and a movable middle insert 180.

[0022] The fixed main mold 120 and the movable main mold 160 are made of structural steel and are formed in a rectangular parallelepiped shape. They each have recesses 121 and 161, which are bottomed holes with a rectangular cross-section extending from opposite sides (the bottom surface for the fixed main mold 120 and the top surface for the movable main mold 160 in Figure 1) to the opposite side (the top surface for the fixed main mold 120 and the bottom surface for the movable main mold 160 in Figure 1).

[0023] Two through holes 122 are provided, extending from the lower surface of the recess 121 to the upper surface of the fixed main mold 120.

[0024] Three through holes 162 are provided, extending from the upper surface of the recess 161 to the lower surface of the movable main mold 160. Two ejector holes 163 are provided, extending from the upper surface of the recess 161 to the lower surface of the movable main mold 160, offset from the through holes 162.

[0025] The fixed insert 130 and the movable insert 170 are made of hardened steel. In this embodiment, the fixed insert 130 has a concave surface facing the movable insert 170, and when the fixed insert 130 and the movable insert 170 come close together, a space is formed, which becomes the cavity 101 of the mold 100. The surfaces of the fixed insert 130 and the movable insert 170 facing the cavity 101 are the cavity surfaces 131 and 171, respectively, which form the outer surface of the molded product.

[0026] The fixed insert 130 has a through hole 132 that extends from the bottom surface to the top surface.

[0027] In this embodiment, the through hole 132 is formed so that a fixed insert 140 made of hardened steel can be inserted through it.

[0028] The movable insert 170 has a through hole 172 that penetrates from the bottom surface to the top surface, and an ejector hole 173 that penetrates from the bottom surface to the top surface, offset from the through hole 172. The through hole 172 is through which the movable insert 180 can be inserted, and the ejector hole 173 is through which the ejector pin 91, described later, can be inserted.

[0029] In this embodiment, a movable intermediate insert 180 (corresponding to the insert in the claims) is provided on the movable insert 170.

[0030] The movable insert 180 is made of hardened steel.

[0031] As shown in Figures 2-4, a cooling circuit 181 is formed inside the movable insert 180 through which a cooling medium such as water or ethanol flows.

[0032] The cooling circuit 181 is equipped with two communication sections 182, 182 that communicate with the outside of the movable insert 180. The cooling circuit 181 is also equipped with a flow restricting section 183 that restricts the flow direction of the cooling medium.

[0033] In this embodiment, the flow restricting section 183 is composed of a Tesla valve.

[0034] Each connecting portion 182, 182 is fitted with a sealing member 190, thereby closing the cooling circuit 181.

[0035] In this embodiment, the sealing member 190 is made of a hexagonal bolt with male threads formed on its entire outer surface. The sealing member 190 also seals the communication portions 182, 182 via a packing 195 made of copper, which is softer and more malleable than the sealing member 190 and the movable insert 180.

[0036] As shown in Figures 3 and 4, the connecting portion 182 is formed as a stepped hole having a small diameter portion 182a and a large diameter portion 182b that is larger in diameter than the small diameter portion 182a.

[0037] The cooling medium is placed in the cooling circuit 181, the packing 195 is placed in the large-diameter portion 182b, and the sealing member 190 is tightened with a hex wrench, thereby sealing the cooling medium and closing the cooling circuit 181.

[0038] As an example of a manufacturing method for the movable insert 180, as shown in Figure 6, cooling circuit forming grooves 181a and 181b are provided on the opposing surfaces of a pair of halves 180a and 180b, respectively, as bottomed grooves extending from the opposing surface to the opposite surface.

[0039] Then, the opposing surfaces of the halved bodies 180a and 180b are joined together. The region enclosed by the cooling circuit forming grooves 181a and 181b constitutes the cooling circuit 181.

[0040] The joined halves 180a and 180b are cut or otherwise shaped into a predetermined form, and as shown in Figure 4, stepped holes are formed from the outer surface toward the cooling circuit 181, and a communication portion 182 is formed by forming an internal screw in the large diameter portion of the stepped hole.

[0041] As shown in Figures 1 and 5, a Peltier element 210 is provided as a cooling element at the lower end of the movable insert 180. The Peltier element 210 cools the movable insert 180 and can generate electricity from the heat. Therefore, the Peltier element 210 can supply power to other equipment such as sensors.

[0042] In this embodiment, it can be said that at least the Peltier element 210 as a cooling element is provided in the area where the sealing member 190 is located and in its vicinity.

[0043] As shown in Figure 1, the overall configuration of the mold cooling structure is such that a fixed mold mounting plate 80 is attached to the upper side of the fixed main mold 120.

[0044] The fixed intermediate insert 140 is positioned to face the cavity 101 by being inserted through the connecting through holes 122 and 132 of the fixed main insert 120 and the fixed insert 130.

[0045] The movable middle insert 180 is positioned to face the cavity 101 by being inserted through the connecting through holes 162 and 172 of the movable main insert 160 and the movable insert 170. In this embodiment, the insert placement section 102 is formed by the through holes 162 and 172.

[0046] A movable support plate 82 is attached to the lower side of the movable main unit 160. Two spacer blocks 84 are attached to the lower side of the movable support plate 82. A movable mounting plate 86 is attached to the lower side of the spacer blocks 84.

[0047] An ejector 90, which has ejector pins 91 for pushing out molded products, is positioned in the space between the movable receiving plate 82 and the movable mounting plate 86.

[0048] The ejector 90 is connected to a drive mechanism (not shown).

[0049] The function and operation of the nested element of this invention will be explained.

[0050] As shown in Figure 3, the liquefied cooling medium flowing from bottom to top on the left side of the cooling circuit 181 evaporates into a vapor state due to the heated synthetic resin at the upper end, and then folds back down and flows.

[0051] The cooling medium, now in a vaporized state, is restricted to flowing only from top to bottom through the Tesla valve section, which acts as a flow restrictor 183, and is then sent to the central lower end section.

[0052] The cooling medium, which has been cooled at the lower central end and returned to a liquefied state, is then restricted to flow only from top to bottom through the Tesla valve section, which acts as a flow restricting section 183 that folds back to the upper side.

[0053] The cooling medium, heated and vaporized at the upper end, folds back down and flows to the lower end, where it cools and liquefies, then flows to the left and returns to its starting point.

[0054] Experiments have confirmed that in the above-described gas-liquid cycle, the sealing member 190 heats up first. By placing the Peltier element 210 in the area that heats up first, the cooling effect is improved.

[0055] In the movable insert 180 of the above configuration, the insert faces the cavity 101 formed in the mold 100, A cooling circuit 181, which has a heat pipe function and is sealed with a cooling medium, is installed inside the movable insert 180. The cooling circuit 181 is provided with multiple communication sections 182 that communicate with the outside of the movable insert 180. Each connecting portion 182 is fitted with a sealing member 190, thereby closing the cooling circuit 181.

[0056] According to this, an insert having a cooling circuit 181 that is reusable and maintainable can be made.

[0057] Furthermore, the sealing member 190 and the movable insert 180 are made of metal. The sealing member 190 seals the communication portion 182, 182 via packings 195, 195 made of a metal that is softer and more malleable than the sealing member 190 and the movable insert 180.

[0058] According to this, the packing 195 deforms to provide a seal, and it can also handle temperature environments where existing rubber O-rings cannot provide a seal, thus contributing to keeping the cooling circuit 181 closed.

[0059] Furthermore, a Peltier element 210 is provided as a cooling element at least in the area of ​​the movable insert 180 where the sealing member 190 is located and in its vicinity.

[0060] According to this, the applicant has found that in testing of the insert according to the present invention, the sealing member 190 heats up first. By placing a cooling member in the part that heats up first, the cooling effect can be improved.

[0061] Furthermore, the cooling circuit 181 is equipped with a flow restricting unit 183 that restricts the flow direction of the cooling medium.

[0062] This prevents the cooling medium from ceasing to circulate.

[0063] If we consider the present invention as a mold cooling structure, it is a mold cooling structure comprising a movable insert 180 facing a cavity 101 formed in a mold 100, The mold 100 has an insert placement section 102 in which the movable insert 180 is placed, and the movable insert 180 is placed in the insert placement section 102.

[0064] According to this, a mold cooling structure that achieves the above-mentioned effect of the insert can be created.

[0065] The mold cooling structure and movable insert 180 of the present invention are not limited to the above configuration. That is, various design modifications are possible as long as they do not depart from the spirit of the present invention.

[0066] For example, although the mold cooling structure is provided on the movable mold 150, it can be provided on the fixed mold 110, or it can be provided on both the fixed mold 110 and the movable mold 150.

[0067] Furthermore, the packing 195 can be made from materials other than copper, such as brass or aluminum, which are softer and more malleable than steel.

[0068] Furthermore, three or more connecting sections 182 can be provided.

[0069] Furthermore, as an alternative to the Peltier element used to cool the inserts, it is also possible to provide passages in the mold through which a cooling medium such as water or air flows. [Explanation of Symbols]

[0070] 100 molds 101 Cavity 102 Nest placement section 180 Movable insert 181 Cooling circuit 182 Communication section 183 Flow Control Section 190 Sealing member 195 Packing 210 Peltier elements

Claims

1. An insert that faces the cavity formed in the mold, A cooling circuit, which has a heat pipe function and is sealed inside the aforementioned insert, The cooling circuit is provided with multiple communication sections that communicate with the outside of the insert. The insert is characterized in that each of the aforementioned communication portions is provided with a sealing member that is detachable from the communication portion, thereby closing the cooling circuit.

2. The sealing member and the insert are made of metal. The insert according to claim 1, characterized in that the sealing member seals the communication portion via a packing made of a metal that is softer and more malleable than the sealing member and the insert.

3. The insert according to claim 1, characterized in that a cooling member is provided at least in the portion of the insert where the sealing member is provided and in the vicinity thereof.

4. The insert according to claim 1, characterized in that the cooling circuit is provided with a flow restricting unit that restricts the flow direction of the cooling medium.

5. A mold cooling structure comprising an insert according to any one of claims 1, 2, 3, or 4 facing a cavity formed in a mold, A mold cooling structure characterized in that the mold has an insert placement section formed therein where the insert is placed, and the insert is placed in the insert placement section.

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