Core 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 a mold insert for use in injection molding of synthetic resins and a mold cooling structure using the same. [Background technology]

[0002] Patent Document 1 describes a mold cooling structure that uses a heat pipe as a cooling circuit.

[0003] According to this, a heat pipe was embedded inside the movable insert, which was able to move back and forth in a direction perpendicular to the parting line, and was attached to a temperature control block provided on the outside of the movable mold plate. A temperature control pipe was formed in the temperature control block, through which a heat medium was circulated. Also, a temperature control block protruding pin was provided on a protruding plate pushed by an ejector rod, and when the protruding plate was pushed, it pushed the movable insert together with the temperature control block, thereby pushing out the optical element formed in the cavity. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-219445 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the heat pipes used in the above-mentioned mold cooling structures, etc., are manufactured by injecting a cooling medium into a hollow tube with one end sealed, evacuating the air remaining inside the hollow tube, and then sealing the other end of the hollow tube.

[0006] When inspecting a heat pipe and finding a defect and wanting to reuse it or perform maintenance on it, the sealed portion at the end of the heat pipe must be broken and opened, which creates the problem that it cannot be reused or maintained.

[0007] In view of the above, an object of the present invention is 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] In the invention described in claim 1, a core facing a cavity formed in a mold is provided, A cooling circuit having a heat pipe function and filled with a cooling medium is disposed inside the insert. The cooling circuit is provided with a plurality of communication parts communicating with the outside of the insert, A sealing member is disposed in each of the communication portions, and the cooling circuit is closed.

[0009] This makes it possible to provide a reusable and maintainable insert having a cooling circuit.

[0010] 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] This allows the gasket to deform and seal, and it can also be used in temperature environments where existing rubber O-rings cannot seal, thereby contributing to closing the cooling circuit.

[0012] A cooling member is disposed at least in the portion of the insert where the sealing member is disposed and in the vicinity thereof.

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

[0014] Further, a flow regulation portion that regulates the flow direction of the cooling medium is disposed in the cooling circuit.

[0015] This can prevent the cooling medium from circulating.

[0016] The invention of claim 5 provides a mold cooling structure including the insert according to any one of claims 1, 2, 3, and 4 facing a cavity formed in a mold, The die has a nesting arrangement portion in which the nesting is arranged, and the nesting is arranged in the nesting arrangement portion.

[0017] This makes it possible to provide a die cooling structure that exhibits the above-mentioned nesting effect. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a schematic explanatory diagram of a mold cooling structure in one embodiment of the present invention. [Diagram 2] FIG. [Diagram 3] FIG. 2 is a vertical cross-sectional view of the insert according to the embodiment. [Figure 4] FIG. 4 is an enlarged view of the vicinity of a communication portion in FIG. 3. [Diagram 5] FIG. 2 is a perspective view showing a state in which a Peltier element is attached. [Figure 6] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] An embodiment of the present invention will be described below with reference to the drawings. A case where the present invention is applied to a mold for injection molding of synthetic resin will be described. In Fig. 1, the left side of the paper is left, the right side is right, the top is top, the bottom is bottom, the front side is front, and the back side is rear.

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

[0021] The fixed mold 110 includes a fixed main mold 120, a fixed mold insert 130, and a fixed inner insert 140. The movable mold 150 includes a movable main mold 160, a movable mold insert 170, and a movable inner insert 180.

[0022] The fixed main mold 120 and the movable main mold 160 are made of steel for mechanical construction, formed into a rectangular parallelepiped shape, and have recesses 121 and 161 formed as bottomed holes with a rectangular cross section from the opposing faces (the lower face for the fixed main mold 120 and the upper face for the movable main mold 160 on the page of FIG. 1) toward the face opposite the opposing faces (the upper face for the fixed main mold 120 and the lower face for the movable main mold 160 on the page of FIG. 1).

[0023] Two through holes 122 are provided, which penetrate 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 that penetrate from the upper surface of the recess 161 to the lower surface of the movable main mold 160. Two ejector holes 163 are provided that penetrate from the upper surface of the recess 161 to the lower surface of the movable main mold 160, offset from the positions of the through holes 162.

[0025] The fixed die core 130 and the movable die core 170 are made of hardened steel. In this embodiment, the surface of the fixed die core 130 facing the movable die core 170 is formed concavely, and when the fixed die core 130 and the movable die core 170 approach each other, a space is formed, which becomes the cavity 101 of the mold 100. The surfaces of the fixed die core 130 and the movable die core 170 facing the cavity 101 are set as cavity surfaces 131 and 171, which form the outer surface of the molded product.

[0026] The fixed insert 130 has a through hole 132 formed therein, which passes through from the lower surface to the upper surface.

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

[0028] The movable die insert 170 is formed with a through hole 172 penetrating from the lower surface to the upper surface, and an ejector hole 173 penetrating from the lower surface to the upper surface is formed at a position offset from the through hole 172. The movable inner die insert 180 can be inserted through the through hole 172, and the ejector hole 173 is adapted to allow an ejector pin 91, which will be described later, to be inserted therethrough.

[0029] In this embodiment, a movable inner die insert 170 is provided with a movable middle insert 180 (corresponding to the insert in the claims).

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

[0031] As shown in FIGS. 2 to 4, within the movable inner member 180, a cooling circuit 181 is formed through which a cooling medium such as water or ethanol flows.

[0032] The cooling circuit 181 is provided with two communication parts 182, 182 that communicate with the outside of the movable inner core 180. The cooling circuit 181 is also provided with a flow regulation part 183 that regulates the flow direction of the cooling medium.

[0033] In this embodiment, the flow restriction portion 183 is configured as a Tesla valve.

[0034] A sealing member 190 is disposed in each of the communication portions 182, 182, and the cooling circuit 181 is closed.

[0035] In this embodiment, the sealing member 190 is configured as a hexagonal bolt having a male thread formed on the entire outer circumferential surface. The sealing member 190 seals the communication parts 182, 182 via a packing 195 made of copper, which is softer and more malleable than the sealing member 190 and the movable inner core 180.

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

[0037] A cooling medium is poured into the cooling circuit 181, a packing 195 is inserted into the large diameter portion 182b, and the sealing member 190 is tightened with a hexagonal wrench, whereby the cooling medium is sealed in and the cooling circuit 181 is closed.

[0038] As an example of a manufacturing method for the movable inner core 180, as shown in FIG. 6, cooling circuit forming grooves 181a, 181b are provided on the opposing surfaces of a pair of half bodies 180a, 180b, respectively, which are formed as bottomed grooves extending from the opposing surfaces to the opposite surfaces.

[0039] The opposing surfaces of the half bodies 180a, 180b are then joined together. The area surrounded by the cooling-circuit forming grooves 181a, 181b constitutes the cooling circuit 181.

[0040] The joined half bodies 180a, 180b are formed into a predetermined shape by cutting or the like, and as shown in FIG. 4, a stepped hole is formed from the outer circumferential surface toward the cooling circuit 181, and a female thread is formed in the large diameter portion of the stepped hole to form a communicating portion 182.

[0041] 1 and 5, a Peltier element 210 is disposed as a cooling member at the lower end of the movable inner core 180. The Peltier element 210 cools the movable inner core 180 and can obtain electricity from heat. Therefore, the Peltier element 210 can supply power to other devices such as sensors.

[0042] In this embodiment, it can be said that at least the portion where the sealing member 190 is disposed and its periphery is provided with a Peltier element 210 as a cooling member.

[0043] As an overall configuration of the mold cooling structure, a fixed mold mounting plate 80 is attached to the upper side of a fixed main mold 120 as shown in FIG.

[0044] A fixed inner die insert 140 is inserted through the communicating through-hole 122 and through-hole 132 of the fixed main die 120 and the fixed die insert 130 so as to face the cavity 101 .

[0045] A movable inner die insert 180 is inserted through the communicating through-hole 162 and through-hole 172 of the movable main die 160 and the movable die insert 170 so as to face the cavity 101. In this embodiment, the through-hole 162 and the through-hole 172 form the insert placement section 102.

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

[0047] An ejector 90 having an ejector pin 91 for ejecting a molded product is disposed in the space between the movable mold receiving plate 82 and the movable mold mounting plate 86 .

[0048] The ejector 90 is connected to a driving means (not shown).

[0049] The function and action of the insert of the present invention will now be described.

[0050] As shown in FIG. 3, the cooling medium in a liquefied state flowing from bottom to top on the left side of the cooling circuit 181 is evaporated by the synthetic resin heated at the top end, turns into a vaporized state, and flows back to the bottom.

[0051] The cooling medium in a vaporized state is restricted so that it flows only from top to bottom through the Tesla valve portion acting as flow restriction portion 183, and is sent to the central lower end portion.

[0052] The cooling medium that is cooled and returned to a liquefied state in the central lower end portion is restricted so that it flows only from top to bottom through the Tesla valve portion that doubles back upward as a flow restriction portion 183.

[0053] The cooling medium is heated at the top and vaporizes, then flows back down, and when it reaches the bottom, it is cooled and liquefied, then flows to the left and returns to the starting point.

[0054] It has been confirmed through experiments that in the above-mentioned gas-liquid cycle, the sealing member 190 heats up first. By disposing the Peltier element 210 in the portion that heats up first, the cooling effect is improved.

[0055] The movable inner insert 180 having the above-mentioned configuration is an insert facing the cavity 101 formed in the die 100, A cooling circuit 181 containing a cooling medium and having a heat pipe function is disposed inside the movable inner core 180. The cooling circuit 181 is provided with a plurality of communication parts 182 that communicate with the outside of the movable inner core 180. A sealing member 190 is disposed in each communication portion 182, and the cooling circuit 181 is closed.

[0056] This makes it possible to provide a reusable and maintainable insert having a cooling circuit 181.

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

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

[0059] Furthermore, a Peltier element 210 is disposed as a cooling member at least at the portion of the movable inner core 180 where the sealing member 190 is disposed and in the vicinity thereof.

[0060] According to this, the applicant has found that in a nesting test according to the present invention, the sealing member 190 heats up first. By disposing a cooling member in the area that heats up first, the cooling effect can be improved.

[0061] Further, the cooling circuit 181 is provided with a flow regulation portion 183 that regulates the flow direction of the cooling medium.

[0062] This can prevent the cooling medium from circulating.

[0063] When the present invention is viewed as a mold cooling structure, it is a mold cooling structure having a movable insert 180 facing a cavity 101 formed in a mold 100, The die 100 is formed with a nesting portion 102 in which a movable inner core 180 is disposed, and the movable inner core 180 is disposed in the nesting portion 102 .

[0064] This makes it possible to provide a die cooling structure that exhibits the above-mentioned nesting effect.

[0065] The mold cooling structure and the movable inner core 180 of the present invention are not limited to the above configuration. In other words, various design changes and the like are possible without departing from the gist of the present invention.

[0066] For example, the mold cooling structure is provided in the movable mold 150 in the above embodiment, but it may be provided in the fixed mold 110 , or may be provided in both the fixed mold 110 and the movable mold 150 .

[0067] In addition, the material of the packing 195 may be brass, aluminum, or other materials that are softer and more malleable than steel, other than copper.

[0068] Furthermore, three or more communication parts 182 may be provided.

[0069] As an alternative to the Peltier element for cooling the insert, a passage through which a cooling medium such as water or air flows can be provided in the mold. [Explanation of symbols]

[0070] 100 Molds 101 Cavity 102 Nest placement section 180 Movable insert 181 Cooling circuit 182 Communication section 183 Flow Restrictor 190 Sealing member 195 Gasket 210 Peltier element

Claims

1. A die insert facing a cavity formed in a die, A cooling circuit having a heat pipe function and filled with a cooling medium is disposed inside the insert. The cooling circuit is provided with a plurality of communication parts communicating with the outside of the insert, The insert is characterized in that a sealing member is provided in each of the communication portions, so that the cooling circuit is in a closed state.

2. The sealing member and the insert are made of metal, 2. The insert according to claim 1, wherein 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. 2. The insert according to claim 1, further comprising a cooling member disposed at least in a portion of the insert where the sealing member is disposed and in the vicinity thereof.

4. 2. The insert according to claim 1, wherein the cooling circuit is provided with a flow regulation portion for regulating a flow direction of the cooling medium.

5. A mold cooling structure comprising the insert according to any one of claims 1, 2, 3 and 4 facing a cavity formed in a mold, A mold cooling structure, characterized in that a nest arrangement portion in which the nest is arranged is formed in the mold, and the nest is arranged in the nest arrangement portion.

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