Magnetic disk, injection mold and injection molding method

Abstract

The invention provides a magnetic disk, an injection mold and an injection molding method, the magnetic disk comprises a magnetic disk body and a plurality of magnetic steels, the magnetic disk body and the plurality of magnetic steels are integrally formed, the injection mold is used for injection molding of the magnetic disk and comprises an upper mold and a lower mold, and an injection molding cavity is formed between the upper mold and the lower mold. At least one piece of non-magnetized magnetic steel can be placed in the injection molding cavity, and the upper mold and the lower mold can be detachably connected with the two ends of the non-magnetized magnetic steel respectively. The magnetic disk has the beneficial effects that the magnetic disk body and the magnetic steel can be subjected to one-time injection molding, so that the stability and corrosion resistance of the magnetic steel are improved, the production efficiency is improved, the installation error of the magnetic pole is avoided, the production cost is reduced, the product quality is ensured, and the service life of the product is prolonged.

Description

Technical Field

[0001] The invention belongs to the field of magnetic disk injection molding, and in particular relates to a magnetic disk, an injection mold and an injection molding method. Background Art

[0002] The traditional method of producing disks is to first complete the disk injection molding, and then place the magnetic steels with anti-corrosion coating on the surface and magnetization treatment one by one into the corresponding circular holes of the disk and press them into the disk. This production method has the following problems:

[0003] 1. The magnetic steel is not installed firmly and is easy to fall off from the disk;

[0004] 2. In an environment with high salinity, the surface of the magnetic steel is easily corroded;

[0005] 3. The magnetic steels need to be installed one by one, resulting in low production efficiency;

[0006] 4. When installing the magnet, the magnetic poles are easily reversed, resulting in a high error rate;

[0007] 5. High production cost;

[0008] 6. Magnetic steel needs to be stored separately, which takes up storage space. Summary of the invention

[0009] In order to solve the above technical problems, the present invention provides a magnetic disk, an injection mold and an injection molding method, which effectively solve the problems of easy falling off and corrosion of magnetic steel, low production efficiency, easy installation errors and high production costs, and overcome the shortcomings of the prior art.

[0010] The technical solution adopted by the present invention is: a magnetic disk, comprising a magnetic disk body and a plurality of magnetic steels, wherein the magnetic disk body and the plurality of magnetic steels are formed in one piece.

[0011] Furthermore, through holes are provided on both sides of the disk body at positions corresponding to the magnetic steels.

[0012] The present invention also provides an injection mold for injection molding the magnetic disk as described above, comprising an upper mold and a lower mold, and an injection cavity is formed between the upper mold and the lower mold, the injection cavity is configured to accommodate at least one unmagnetized magnetic steel, and the upper mold and the lower mold are configured to be detachably connected to the two ends of the unmagnetized magnetic steel, respectively.

[0013] Furthermore, the upper mold and the lower mold are respectively provided with adsorption parts at corresponding positions, and the adsorption parts of the upper mold and the lower mold are configured to respectively adsorb the two ends of the unmagnetized magnetic steel.

[0014] Furthermore, the adsorption portion is configured to be cylindrical with a diameter smaller than that of the unmagnetized magnetic steel.

[0015] Furthermore, the upper mold is provided with a positioning portion, and the positioning portion is located at the periphery of the adsorption portion.

[0016] Furthermore, the positioning portion includes a plurality of positioning posts, and the plurality of positioning posts of a positioning portion are arranged at intervals along the circumference of an adsorption portion.

[0017] Furthermore, a side of the positioning column facing the adsorption portion is configured to be in a shape that can be matched with the surface of the unmagnetized magnetic steel.

[0018] The present invention also provides a disk injection molding method, using the disk injection mold as described above to injection mold the disk as described above, comprising the following steps:

[0019] Inserting unmagnetized magnetic steel into the injection cavity of the magnetic disk injection mold;

[0020] Injecting a molding material for forming the disk body into the molding cavity of the disk injection mold, wherein the molding material is integrated with the unmagnetized magnetic steel;

[0021] After the injection molding is completed, the unmagnetized magnetic steel is magnetized to form the magnetic steel.

[0022] Furthermore, the unmagnetized magnetic steel is magnetized through the through hole on the magnetic disk body.

[0023] Furthermore, when the unmagnetized magnetic steel is inserted, the unmagnetized magnetic steel is coaxially arranged with the adsorption portion.

[0024] The advantages and positive effects of the present invention are: due to the adoption of the above technical scheme, the magnetic disk and the magnetic steel can be injection molded at one time, which improves the stability and corrosion resistance of the magnetic steel, improves production efficiency, avoids installation errors of the magnetic pole, reduces production costs, ensures product quality, and extends the service life of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The figure is a schematic diagram of the overall structure of a disk injection mold according to an embodiment of the present invention.

[0026] Figure 2 The present invention is a schematic diagram of the placement of unmagnetized magnetic steel in a disk injection mold according to an embodiment of the present invention.

[0027] Figure 3 It is a partial enlarged view of a disk injection mold A according to an embodiment of the present invention.

[0028] Figure 4 The present invention is a schematic structural diagram of an upper mold of a disk injection mold according to an embodiment of the present invention.

[0029] Figure 5 It is a partial enlarged view of a disk injection mold B according to an embodiment of the present invention.

[0030] Figure 6 The present invention is a schematic structural diagram of a lower mold of a disk injection mold according to an embodiment of the present invention.

[0031] Figure 7 It is a partial enlarged view of a disk injection mold C according to an embodiment of the present invention.

[0032] Figure 8 It is a schematic diagram of the structure of one side of a disk according to an embodiment of the present invention.

[0033] Fig. 9 It is a schematic diagram of the structure of the other side of a disk according to an embodiment of the present invention.

[0034] In the figure:

[0035] 1. Upper fixed plate 2. Lower fixed plate 3. Die foot

[0036] 4. Support plate 5. Upper mold 6. Lower mold

[0037] 7. Injection cavity 8. Unmagnetized magnetic steel 9. Positioning column

[0038] 10. Adsorption part 11. Through hole 12. Positioning column groove

[0039] 13. Nozzle 14. Disk body DETAILED DESCRIPTION

[0040] The embodiments of the present invention provide a magnetic disk, an injection mold and an injection molding method. The embodiments of the present invention are described below with reference to the accompanying drawings.

[0041] In the description of the embodiments of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "set" and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0042] like Figure 1-3As shown, an embodiment of the present invention is a disk injection mold, comprising an upper mold 5 and a lower mold 6, and an injection cavity 7 is formed between the upper mold 5 and the lower mold 6, the injection cavity 7 is configured to accommodate at least one unmagnetized magnetic steel 8, and the upper mold 5 and the lower mold 6 are configured to be detachably connected to the two ends of the unmagnetized magnetic steel 8 respectively.

[0043] like Figure 4-7 As shown, the upper mold 5 and the lower mold 6 are respectively provided with adsorption parts 10 at corresponding positions, and the adsorption parts 10 are configured to adsorb the two ends of the unmagnetized magnetic steel 8. The upper mold 5 and the lower mold 6 are respectively provided with adsorption parts 10 at positions corresponding to the unmagnetized magnetic steel 8, and the adsorption parts 10 of the upper mold and the lower mold can adsorb the ends of the unmagnetized magnetic steel 8 respectively. The upper mold 5 is integrally provided with the adsorption part 10 thereon, and the lower mold 6 is integrally provided with the adsorption part 10 thereon. After the magnetic adsorption treatment, the adsorption part 10 has weak magnetism. When the unmagnetized magnetic steel 8 is placed, the adsorption part 10 can adsorb the ends of the unmagnetized magnetic steel 8, which is more conducive to the placement of the unmagnetized magnetic steel 8. After the mold is closed, the adsorption parts 10 of the upper mold 5 and the lower mold 6 are respectively in contact with the two ends of the unmagnetized magnetic steel 8, and the two ends of the unmagnetized magnetic steel 8 are adsorbed and fixed. During the injection molding process, the adsorption part 10 can firmly adsorb the unmagnetized magnetic steel 8 to prevent the unmagnetized magnetic steel 8 from being displaced under the action of the injection molding material, thereby affecting the product performance.

[0044] Specifically, the adsorption portion 10 is configured to be cylindrical with a diameter smaller than that of the unmagnetized magnetic steel 8. The adsorption portion 10 and the unmagnetized magnetic steel 8 are coaxially configured. Since the diameter of the adsorption portion 10 is smaller than the diameter of the unmagnetized magnetic steel 8, the two ends of the unmagnetized magnetic steel 8 are not completely covered by the adsorption portion 10, and the injection molding material can reach the two end surfaces of the unmagnetized magnetic steel 8, so that the two end surfaces of the unmagnetized magnetic steel 8 can also be partially wrapped by the injection molding material, so that the unmagnetized magnetic steel and the injection molding material are more firmly combined. At the same time, the position of the magnetic disk relative to the adsorption portion 10 is a through hole 11, through which the unmagnetized magnetic steel 8 can be magnetized, rust-proofed, anti-corrosion and other treatments. And the diameter of this through hole 11 is smaller than the diameter of the unmagnetized magnetic steel 8, and the unmagnetized magnetic steel 8 is not easy to fall off from the magnetic disk.

[0045] like Figure 4-5 As shown, the upper mold 5 is provided with a positioning portion, and the positioning portion is located at the periphery of the adsorption portion 10. In order to achieve accurate positioning of the unmagnetized magnetic steel 8 and ensure the performance of the magnetic disk, a positioning portion is provided at the position of the upper mold 5 corresponding to the unmagnetized magnetic steel 8, and the positioning portion is arranged on the outer side of the adsorption portion 10 along the circumferential direction of the unmagnetized magnetic steel 8.

[0046] Specifically, the positioning portion includes a plurality of positioning posts 9, and the plurality of positioning posts 9 of one positioning portion are arranged at intervals along the circumference of one adsorption portion 10. The specific number of the positioning posts 9 is not limited.

[0047] In order to achieve more accurate positioning without damaging the surface of the unmagnetized magnetic steel 8 , the side of the positioning column 9 facing the adsorption portion 10 is configured to be a shape that can adapt to the surface of the unmagnetized magnetic steel 8 .

[0048] Embodiment: A magnetic disk injection mold comprises an upper fixed plate 1 and a lower fixed plate 2. A mold foot 3 is provided on the lower fixed plate 2, a support plate 4 is provided on the mold foot 3, an upper mold 5 is provided at the lower part of the upper fixed plate 1, and a lower mold 6 is provided on the support plate 4. Four groups of injection holes 7 are provided at the relative positions of the upper mold 5 and the lower mold 6. The injection hole 7 is configured to accommodate at least one unmagnetized magnetic steel 8, and the upper mold 5 and the lower mold 6 are configured to be detachably connected to the two ends of the unmagnetized magnetic steel 8, respectively. The unmagnetized magnetic steel 8 is cylindrical and vertically arranged, and a plurality of magnetized magnetic steels 8 are evenly distributed along the circumference of the injection hole 7. The upper mold 5 and the lower mold 6 are respectively provided with adsorption parts 10 at corresponding positions, and the adsorption parts 10 are configured to adsorb the two ends of the unmagnetized magnetic steel 8. The adsorption parts 10 are integrally arranged with the upper mold 5 and the lower mold 6, and the adsorption parts 10 are cylindrical and coaxially arranged with the unmagnetized magnetic steel 8. The diameter of the adsorption part 10 is smaller than the diameter of the unmagnetized magnetic steel 8. The upper mold 5 is provided with a positioning portion, which is located at the periphery of the adsorption portion 10. The positioning portion includes three positioning posts 9, and the three positioning posts 9 of one positioning portion are evenly spaced along the circumference of one adsorption portion 10. The side of the positioning post 9 facing the adsorption portion 10 is arranged in an arc shape that can adapt to the surface of the unmagnetized magnetic steel 8.

[0049] A disk, such as Figure 8 and 9 As shown, it includes a disk body 14 and a plurality of magnets, and the disk body 14 and the plurality of magnets are integrally formed. It can be formed by injection molding using the disk injection mold as described above. The disk body 14 is circular, the magnet is cylindrical, and the magnet is arranged inside the disk body 14. The magnet is arranged vertically perpendicular to the end face of the disk body, and the plurality of magnets are evenly distributed along the circumference of the disk body. Through holes 11 are provided at positions corresponding to the adsorption portion 10 on both sides of the disk body, and the shape of the through holes 11 is adapted to the shape of the adsorption portion 10. The diameter of the through hole 11 is smaller than the diameter of the magnet. A positioning column groove 12 is provided at a position corresponding to the positioning column 9 on one side of the disk body, and the shape of the positioning column groove 12 is adapted to the positioning column 9. After the injection molding is completed, the unmagnetized magnet 8 can be magnetized, rust-proofed and anti-corroded through the through hole 11. The unmagnetized magnet 8 after magnetization is the magnet of the disk.

[0050] An injection molding method, using the disk injection mold as described above to perform one-time injection molding. Before injection molding, the adsorption portion 10 is subjected to magnetic attraction treatment to ensure that the adsorption portion 10 can adsorb the unmagnetized magnetic steel 8. The lower mold 6 is placed on the support plate 4. The unmagnetized magnetic steel 8 can be placed on the adsorption portion 10 of the upper mold by any known and feasible loading method such as manual loading, tooling loading or robot. Because a plurality of unmagnetized magnetic steels 8 are evenly distributed along the circumference of the disk body, the unmagnetized magnetic steels 8 are evenly distributed along the circumference of the injection cavity 7 according to the setting of the magnetic steel on the disk. The side of the positioning column 9 facing the adsorption portion 10 is adapted to the surface of the unmagnetized magnetic steel 8 to accurately position the unmagnetized magnetic steel 8. Then the upper mold 5 is placed on the lower mold 6. The adsorption portions 10 of the upper mold 5 and the lower mold 6 adsorb and fix the two ends of the unmagnetized magnetic steel 8. The adsorption part 10 of the upper mold 5 and the lower mold 6 is coaxially arranged with the unmagnetized magnetic steel 8, so as to ensure that the unmagnetized magnetic steel 8 is at the set position of the disk body after successful injection molding. Then the upper fixed plate 1 is placed above the upper mold 5. After the mold is closed, the heated injection molding material used to form the disk body is injected into the injection cavity 7 through the nozzle 13, and the injection molding material is combined with the unmagnetized magnetic steel 8 as one body. After the injection molding is completed, the mold is demolded, and the unmagnetized magnetic steel is magnetized to form the magnetic steel. In this way, the disk in which the disk body 14 and the magnetic steel are integrally formed is obtained, and the disk body 14 and the unmagnetized magnetic steel 8 are injection molded at one time.

[0051] During magnetization, a magnetization device is used to magnetize the unmagnetized magnetic steel 8 through the through hole 11 on the disk body. If the protective film on the surface of the magnetic steel is damaged, an anti-rust and anti-corrosion treatment, such as a glue coating treatment, can be performed through the through hole 11.

[0052] The advantages and positive effects of the present invention are:

[0053] 1. The magnet is integrated with the disk body so that the magnet is embedded inside the disk and is not easy to fall off.

[0054] 2. The magnetic steel is accurately positioned and fixed through the positioning part and the adsorption part to ensure the quality of the product.

[0055] 3. Since the magnet is inside the disk body, there is less exposed surface and it is not easily corroded by the outside world. The magnet does not need to be pressed in, so it has less wear and tear, which extends the service life of the product.

[0056] 4. There is no need to install the magnetic steels one by one, which simplifies the operation steps, improves production efficiency and saves production costs.

[0057] 5. After the injection molding is completed, the magnets are uniformly magnetized to avoid errors caused by reversed magnetic poles.

[0058] 6. The magnet is set inside the disk body, and no additional storage space is required.

[0059] The embodiments of the present invention are described in detail above, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A magnetic disk, comprising a magnetic disk body and a plurality of magnetic steels, characterized in that: The disk body and a plurality of magnetic steels are formed in one piece.

2. A magnetic disk according to claim 1, characterized in that: Through holes are arranged on both sides of the disk body at positions corresponding to the magnetic steels.

3. An injection mold for injection molding the magnetic disk as claimed in claim 1 or 2, comprising an upper mold and a lower mold, wherein an injection cavity is formed between the upper mold and the lower mold, characterized in that: The injection cavity is configured to accommodate at least one unmagnetized magnetic steel, and the upper mold and the lower mold are configured to be detachably connected to two ends of the unmagnetized magnetic steel respectively.

4. The disk injection mold according to claim 3, characterized in that: The upper mold and the lower mold are respectively provided with adsorption parts at corresponding positions, and the adsorption parts of the upper mold and the lower mold are configured to respectively adsorb the two ends of the unmagnetized magnetic steel.

5. The disk injection mold according to claim 4, characterized in that: The adsorption portion is configured to be a cylindrical shape having a diameter smaller than that of the unmagnetized magnetic steel.

6. A disk injection mold according to claim 4 or 5, characterized in that: The upper mold or the lower mold is provided with a positioning portion, and the positioning portion is located at the periphery of the adsorption portion.

7. The disk injection mold according to claim 6, characterized in that: The positioning portion comprises a plurality of positioning posts, and the plurality of positioning posts of a positioning portion are arranged at intervals along the circumference of an adsorption portion.

8. The magnetic disk injection mold according to claim 7, characterized in that: The side of the positioning column facing the adsorption portion is configured to be in a shape that can be matched with the surface of the unmagnetized magnetic steel.

9. A disk injection molding method, characterized in that: Using the disk injection mold as described in any one of claims 3 to 8, injection molding the disk as described in claim 1 or 2 comprises the following steps: Inserting unmagnetized magnetic steel into the injection cavity of the magnetic disk injection mold; Injecting a molding material for forming the disk body into the molding cavity of the disk injection mold, wherein the molding material is integrated with the unmagnetized magnetic steel; After the injection molding is completed, the unmagnetized magnetic steel is magnetized to form the magnetic steel.

10. An injection molding method according to claim 9, characterized in that: The unmagnetized magnetic steel is magnetized through the through hole on the magnetic disk body; preferably, when the unmagnetized magnetic steel is inserted, the unmagnetized magnetic steel is coaxially arranged with the adsorption portion.

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