A hot forming mold based on magnetocaloric effect

Abstract

The present invention discloses a thermoforming mold based on magnetocaloric effect, comprising a molding mold and a heating die head. The molding mold is composed of a plurality of molding molds, wherein an electromagnetic heating coil is arranged inside the molding mold. The heating die head cooperates with the molding mold, and the heating die head comprises a heating core rod, which extends into the mold cavity of the molding mold. The present invention has a reasonable design and a detailed principle. Based on the magnetocaloric effect, the invention is not directly applied to material heating, but the heating core rod is heated by the electromagnetic heating coil, and then the sealed blank is expanded and formed, thus filling the application gap of the magnetocaloric effect in the expansion forming direction and continuing the advantages of the magnetocaloric effect, so that the thermoforming mold has the advantages of environmental protection, accurate temperature control, high energy utilization rate, no need for combustion, no noise, etc., and is very suitable for promotion and application in the field of expansion forming.

Description

Technical Field

[0001] The invention relates to the technical field of forming dies, in particular to a hot forming die based on magnetocaloric effect. Background Art

[0002] The magnetocaloric effect refers to the phenomenon that the temperature of a ferromagnet or paramagnet changes with the change of magnetic field strength during adiabatic process. In industry, materials are often heated by electromagnetic heating coils, which are common in plastic machinery and equipment, food machinery, chemical industry, aluminum industry and other industries. It is widely used because it does not require combustion, has no waste, does not pollute the environment, and has no noise.

[0003] Electromagnetic heating technology relies on the principle of electromagnetic heating and has the advantages of environmental protection, accurate temperature control, high energy utilization, and easy modular design. However, it is often directly applied to material heating and has relatively few applications in the field of molding molds, especially in bulging molding, which is almost blank. Summary of the invention

[0004] In view of the above problems, the present invention discloses a thermoforming mold based on magnetocaloric effect.

[0005] The specific technical solutions are as follows:

[0006] A thermoforming mold based on magnetocaloric effect, characterized in that it comprises a forming mold and a heating die head, wherein the forming mold is composed of a plurality of forming molds, an electromagnetic heating coil is arranged inside the forming mold, the electromagnetic heating coil corresponds to the plurality of forming molds, is segmented, and is combined into one with the forming molds and is connected through an elastic conductive member;

[0007] The heating die head is matched with the forming die, and the heating die head comprises a heating core rod, and the heating core rod extends into the die cavity of the forming die.

[0008] The above-mentioned hot forming mold based on magnetocaloric effect, wherein the forming mold is made of non-magnetic and non-conductive materials, including but not limited to silicon nitride ceramics, fiberglass and asbestos.

[0009] The above-mentioned thermoforming mold based on magnetocaloric effect, wherein one end of the elastic conductive part is fixedly connected to the segmented electromagnetic heating coil and electrically interacts with it, and the other end thereof elastically contacts and electrically interacts with the adjacent segmented electromagnetic heating coil when the molding mold is closed, thereby realizing the conduction of the electromagnetic heating coil when the molding mold is closed.

[0010] In the above-mentioned thermoforming mold based on magnetocaloric effect, the elastic conductive member is one or more of a spring contact and an elastic metal contact sheet having an electrical contact function.

[0011] The above-mentioned thermoforming mold based on magnetocaloric effect, wherein the elastic conductive part is composed of a male plug and a female plug; the male plug and the female plug are respectively arranged at the ends of the electromagnetic heating coils in adjacent forming molds, and are both fixedly connected to the electromagnetic heating coils and electrically interact with each other to realize the conduction of the electromagnetic heating coil when the forming mold is in the closed state.

[0012] In the above-mentioned thermoforming mold based on magnetocaloric effect, the male plug is a conductive contact, and the female plug is an elastic conductive socket. When the forming mold is closed, the conductive contact and the elastic conductive socket are plugged in and electrically interact with each other.

[0013] The above-mentioned thermoforming mold based on magnetocaloric effect, wherein the forming mold is composed of two forming molds, the electromagnetic heating coil is embedded in the forming mold and has a spiral structure, the electromagnetic heating coil corresponds to the forming mold, is divided into two sections, and when the forming mold is closed, the conduction is completed through the elastic conductive piece.

[0014] The above-mentioned thermoforming mold based on magnetocaloric effect, wherein the molding mold is respectively provided with guide pins and guide sleeves, and the molding molds are precisely clamped together by the guide pins and guide sleeves.

[0015] The above-mentioned thermoforming mold based on magnetocaloric effect, wherein a pressure plate is fixedly connected to the outer side surface of the forming mold, and the forming mold is connected to the transmission equipment through the pressure plate to perform mold closing and mold separation actions, and a die head fixing plate is fixedly connected to the heating die head, and the heating die head is connected to the transmission equipment through the die head fixing plate to perform mold closing and mold separation actions.

[0016] The beneficial effects of the present invention are:

[0017] The present invention discloses a thermoforming mold based on magnetocaloric effect, comprising a molding mold and a heating die head. The molding mold is composed of a plurality of molding molds, wherein an electromagnetic heating coil is arranged inside the molding mold. The heating die head cooperates with the molding mold, and the heating die head comprises a heating core rod, which extends into the mold cavity of the molding mold. The present invention has a reasonable design and a detailed principle. Based on the magnetocaloric effect, the invention is not directly applied to material heating, but the heating core rod is heated by the electromagnetic heating coil, and then the sealed blank is expanded and formed, thus filling the application gap of the magnetocaloric effect in the expansion forming direction and continuing the advantages of the magnetocaloric effect, so that the thermoforming mold has the advantages of environmental protection, accurate temperature control, high energy utilization rate, no need for combustion, no noise, etc., and is very suitable for promotion and application in the field of expansion forming. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is an exploded view of the present invention.

[0019] Figure 2 It is a schematic diagram of the present invention.

[0020] Figure 3 This is a schematic diagram of an elastic conductive member.

[0021] Figure 4 This is the second schematic diagram of the elastic conductive component.

[0022] Figure 5 This is the third schematic diagram of the elastic conductive component.

[0023] Figure 6 This is a perspective view of the molding die.

[0024] Explanation of the accompanying drawings: 1. Molding mold; 2. Molding mold; 3. Electromagnetic heating coil; 4. Heating die head; 5. Hot core rod; 6. Elastic conductive part; 7. Spring contact; 8. Elastic metal contact piece; 9. Male plug; 10. Female plug; 11. Guide column; 12. Guide sleeve; 13. Pressing plate; 14. Die head fixing plate. DETAILED DESCRIPTION

[0025] In order to make the technical solution of the present invention clearer and more specific, the present invention is further described below in conjunction with embodiments. Any equivalent replacement of the technical features of the technical solution of the present invention and any solution derived by conventional reasoning shall fall within the protection scope of the present invention.

[0026] Embodiment 1

[0027] like Figure 1-Figure 2 As shown, a thermoforming mold based on magnetocaloric effect of the present embodiment is designed based on magnetocaloric effect, and the blank inside is expanded and formed by an expansion forming method. Specifically, the thermoforming mold includes a forming mold 1 and a heating die head 4. The forming mold 1 is composed of a plurality of forming molds 2, and an electromagnetic heating coil 3 for electromagnetic heating of the heating die head 4 is arranged therein. The electromagnetic heating coil 3 corresponds to the plurality of forming molds 2, is segmented, and is divided into multiple sections, and is combined into one with the forming mold 2 by closing the mold. At the same time, electrical interaction is performed through the elastic conductive member 6, thereby achieving conduction;

[0028] The heating die head 4 is used as a receptor to be electromagnetically heated, and cooperates with the forming mold 1 and is arranged at the opening position of the mold cavity of the forming mold 1. The heating die head 4 includes a heating core rod 5, and the heating core rod 5 extends into the mold cavity of the forming mold 1;

[0029] Taking the preform as an example, when the preform is being molded, the preform is placed in the mold cavity of the molding mold 1, the heating die head 4 moves and fits tightly with the molding mold 1, and the opening of the preform is sealed to ensure the sealing inside the preform and the bulging effect; at this time, the electromagnetic heating coil 3 works to quickly heat up the heating core rod 5, and then the preform is heated (heated by thermal radiation) to the softening temperature, and the gas inside the preform expands rapidly, and finally, the preform is expanded and molded in the molding mold 1.

[0030] Embodiment 2

[0031] A hot forming mold based on magnetocaloric effect in this embodiment, wherein the forming mold 1 is made of non-magnetic and non-conductive materials, including but not limited to silicon nitride ceramics, fiberglass and asbestos, and based on the expansion forming of blanks of different materials (the blank material needs to be non-magnetic material to avoid electromagnetic heating), the forming mold 1 made of different materials can be selected;

[0032] Taking the bottle embryo made of aluminum alloy 3004 as an example, its softening temperature is about 400° C. At this time, silicon nitride ceramics with a temperature resistance of more than 1000° C. can be selected to make the forming mold 1.

[0033] Embodiment 3

[0034] like Figure 1 , Figure 3-Figure 4 As shown, a thermoforming mold based on magnetocaloric effect of this embodiment adopts a technical solution of elastic electrical contact to realize the conduction between the segmented electromagnetic heating coils 3. Specifically, one end of the elastic conductive member 6 is fixedly connected to the segmented electromagnetic heating coil 3 and electrically interacts with it, and the other end thereof elastically contacts and electrically interacts with the adjacent segmented electromagnetic heating coil 3 when the forming mold 2 is in the closed state, thereby realizing the conduction of the electromagnetic heating coil 3 when the forming mold 2 is in the closed state;

[0035] The specific elastic electrical contact scheme is as follows:

[0036] In one embodiment, the elastic conductive member 6 is selected from one or more of a spring contact 7 and an elastic metal contact sheet 8 having an electrical contact function, one end of which is fixedly connected to the electromagnetic heating coil 3 by means of threaded connection, welding, riveting, etc., and the other end is elastically electrically contacted with the adjacent electromagnetic heating coil 3 when the molding mold 1 is closed to complete conduction;

[0037] In the second scheme, the elastic conductive part 6 is composed of a male plug 9 and a female plug, and electrical conduction is achieved by plugging male and female plugs; wherein, the male plug 9 and the female plug 10 are respectively arranged at the ends of the electromagnetic heating coil 3 in the adjacent molding mold 2, and are both fixedly connected with the electromagnetic heating coil 3 and electrically interact with each other, wherein, the male plug 9 is a conductive contact, and the female plug 10 is an elastic conductive socket, and when the molding mold 2 is closed, the conductive contact and the elastic conductive socket are plugged in and connected and electrically interact with each other, so as to realize the conduction of the electromagnetic heating coil 3 when the molding mold 2 is in the closed state.

[0038] Embodiment 4

[0039] like Figure 1 and Figure 6As shown, a thermoforming mold based on magnetocaloric effect is used in this embodiment. Preferably, the molding mold 1 is composed of two molding molds 2. The electromagnetic heating coil 3 is embedded in the molding mold 1 and has a spiral structure. The electromagnetic heating coil 3 corresponds to the molding mold 2 and is divided into two sections. When the molding mold 2 is closed, the conduction is completed through the elastic conductive piece 6.

[0040] In order to improve the mold clamping accuracy of the forming mold 2, guide pillars and guide sleeves are respectively provided on the forming mold 2, and the forming molds 2 are precisely clamped by the guide pillars 11 and the guide sleeves 12;

[0041] At the same time, a pressure plate 13 is fixedly connected to the outer side of the forming mold 2, and the forming mold 2 is connected to the transmission equipment through the pressure plate 13 to perform mold closing and mold separation actions. A die head fixing plate 14 is fixedly connected to the heating die head 4, and the heating die head 4 is connected to the transmission equipment through the die head fixing plate 14 to perform mold closing and mold separation actions; the transmission equipment described in this embodiment is a cylinder or a hydraulic cylinder.

[0042] Embodiment 5

[0043] Based on the first, second and fourth embodiments, a thermoforming mold based on the magnetocaloric effect of this embodiment has a working method as follows:

[0044] S1. The forming mold 1 is made of silicon nitride ceramic. In the mold separation state, the bottle preform made of aluminum alloy 3004 is placed in the mold cavity, and then the mold is closed and locked. The heating die head 4 is lowered to fit tightly with the forming mold 1, and the opening position of the bottle preform is sealed at the same time. The heating core rod 5 is inserted into the bottle preform;

[0045] S2, in the mold closing state, the electromagnetic heating coil 3 is turned on and works. Based on the magnetocaloric effect, the heating core rod 5 is heated to 500°C, and the preform is heated to a softening temperature of 400°C through thermal radiation. At the same time, the gas in the preform expands due to the heat, causing the softened preform to bulge and finally be formed.

[0046] S3, after expansion forming, the electromagnetic heating coil 3 is turned off, and after cooling, the forming mold 1 is separated, and the formed aluminum bottle is taken out, and finally, it is sent for shaping and trimming to obtain a finished aluminum bottle.

[0047] In step S2 of this embodiment, the gas pressure during the bulging process is calculated based on the ideal gas state equation (PV=nRT, p1*v1 / T1=p2*v2 / T2). When the gas temperature in the preform rises to 500°C, the gas pressure will increase by about 2.5 times while the volume remains unchanged. Therefore, the conditions for bulging molding are met.

[0048] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A thermoforming mold based on magnetocaloric effect, characterized in that: The invention comprises a forming die (1) and a heating die head (4), wherein the forming die (1) is composed of a plurality of forming dies (2) and an electromagnetic heating coil (3) is arranged therein, the electromagnetic heating coil (3) corresponds to the plurality of forming dies (2), is segmented, and is combined into one body with the forming dies (2) when the forming dies (2) are closed, and conduction is achieved through an elastic conducting member (6); The heating die head (4) and the forming die (1) cooperate with each other, and the heating die head (4) comprises a heating core rod (5), and the heating core rod (5) extends into the die cavity of the forming die (1); The molding die (1) is made of a non-magnetic and non-conductive material, which is silicon nitride ceramic, glass fiber reinforced plastic or asbestos; one end of the elastic conductive member (6) is fixedly connected to and electrically interacts with the segmented electromagnetic heating coil (3); and the other end thereof elastically contacts and electrically interacts with the adjacent segmented electromagnetic heating coil (3) when the molding die (2) is in a closed state, thereby achieving conduction of the electromagnetic heating coil (3) when the molding die (2) is in a closed state; Thermoforming molds work as follows: S1. The forming mold (1) is made of silicon nitride ceramic material. In the mold separation state, a bottle preform made of aluminum alloy 3004 is placed in the mold cavity position, and then the mold is closed and locked. The heating die head (4) is lowered to fit tightly with the forming mold (1), and the opening position of the bottle preform is sealed at the same time. The heating core rod (5) is extended into the bottle preform; S2, in the mold closing state, the electromagnetic heating coil (3) is turned on and works, and based on the magnetocaloric effect, the heating core rod (5) is heated to 500°C, and the bottle embryo is heated to a softening temperature of 400°C through thermal radiation. At the same time, the gas in the bottle embryo expands due to the heat, causing the softened bottle embryo to swell and finally be formed; S3, after the expansion forming, the electromagnetic heating coil (3) is turned off, and after cooling, the forming mold (1) is separated, and the formed aluminum bottle is taken out, and finally, it is sent for shaping and trimming to obtain the finished aluminum bottle.

2. A thermoforming mold based on magnetocaloric effect as claimed in claim 1, characterized in that: The elastic conductive member (6) is one or more of a spring contact (7) and an elastic metal contact sheet (8) having an electrical contact function.

3. A thermoforming mold based on magnetocaloric effect as claimed in claim 1, characterized in that: The elastic conductive member (6) is composed of a male plug (9) and a female plug; the male plug (9) and the female plug (10) are respectively arranged at the ends of the electromagnetic heating coils (3) in adjacent forming dies (2), and are both fixedly connected to the electromagnetic heating coils (3) and electrically interact with each other, so as to realize the conduction of the electromagnetic heating coils (3) when the forming dies (2) are in a closed state.

4. A thermoforming mold based on magnetocaloric effect as claimed in claim 3, characterized in that: The male plug (9) is a conductive contact, and the female plug (10) is an elastic conductive socket. When the molding die (2) is closed, the conductive contact and the elastic conductive socket are plugged in and electrically interact with each other.

5. A thermoforming mold based on magnetocaloric effect as claimed in claim 1, characterized in that: The molding die (1) is composed of two molding dies (2) combined together. The electromagnetic heating coil (3) is embedded in the molding die (1) and has a spiral structure. The electromagnetic heating coil (3) corresponds to the molding die (2) and is divided into two sections. When the molding die (2) is closed, conduction is completed through the elastic conduction piece (6).

6. A thermoforming mold based on magnetocaloric effect as claimed in claim 5, characterized in that: The molding dies (2) are respectively provided with guide pillars and guide sleeves, and the molding dies (2) are precisely clamped together by means of the guide pillars (11) and the guide sleeves (12).

7. A thermoforming mold based on magnetocaloric effect as claimed in claim 6, characterized in that: A pressing plate (13) is fixedly connected to the outer surface of the forming die (2), and the forming die (2) is connected to the transmission equipment through the pressing plate (13) to perform mold closing and mold opening actions. A die head fixing plate (14) is fixedly connected to the heating die head (4), and the heating die head (4) is connected to the transmission equipment through the die head fixing plate (14) to perform mold closing and mold opening actions.

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