JPH03265447A - Core-coil assembly for linear motor and molding method therefor - Google Patents

Abstract

PURPOSE:To eliminate preparation of a pouring mold by using a boxlike vessel made of plastic, incorporating a core.coil semifabricated product therein, pouring thermosetting resin in the vessel as a pouring mold, and integrating these three elements. CONSTITUTION:A boxlike vessel 11 made of plastic is used as a resin pouring mold. A coil 21 is wound on a core and a core.coil semifabricated product 22 adhered with a thermostat (not shown in figure) is contained in the vessel 11 with the leg 23 of the product disposed upside. Then, thermosetting resin 24 such as epoxy resin is poured, thermoset, the vessel 11 and the product 22 are integrally coupled to obtain a core.coil assembly 20. Thus, since the vessel is used as the mold and used as a shell of the assembly by outserting as part of the product as it is, it is not necessary to prepare a pouring mold nor to manage it. Since a mold releasing is not required, heating work for adhering mold release agent can be omitted.

Description

[Detailed Description of the Invention] [Industrial Application Field 1] The present invention is a method of applying plastic material to the recesses and gaps of a core/coil semi-finished product (hereinafter referred to as a "core/coil semi-finished product") in which a linear motor conductor wire is wound. Regarding the mold construction method in which the core and coil assembly is completed by filling, more specifically, a conventional iron rectangular frame-shaped mold is placed on a base plate, and the core and coil semi-finished products are placed inside this frame-shaped mold and heated. Instead of injecting hardened plastic ink and releasing it from the molding die after heating and curing to form a core coil assembly, we created a box-shaped mold made of Plasdec (hereinafter referred to as the box-shaped container).
The present invention relates to a molding method in which the assembly is integrally molded with the mold inserted as an outsert into the assembly.

[Prior art] A predetermined number of turns of conductor wire is wound around the outer circumference of the core, and the core and coil semi-finished product with lead wires, thermostats, mark bands, etc. attached are firmly bonded with epoxy thermosetting plastic to form the core. In order to complete the coil assembly, in the conventional method, a rectangular iron formwork surrounded by side walls and open at the top and bottom is prepared, and the formwork is pre-applied with a mold release agent such as silicone. Bake at a temperature of 200℃.

This mold release agent is applied by placing a semi-finished product with a coil wrapped around the core in a mold, injecting thermosetting resin, and then heating and curing it to completely fill and fix the core and coil, forming the core/coil assembly into the mold. This is to facilitate removal from the frame.

As shown in FIG. 3, a mold frame 30 with a mold release agent (not shown) baked into the long side walls 31 and short side walls 32 is placed on a flat and relatively thick base plate 35.

Next, after pre-drying the mold frame 30 and the base plate 35 at a temperature of about 120°C, a resin (not shown) is injected and held at 120°C for about 5 hours to heat cure. As a result, the core-coil assembly (not shown), which is joined together and surrounded by a thermosetting resin, is removed from the mold.

[Problems to be Solved by the Invention] As already mentioned, the mold release agent is burned off on the inner wall of the metal mold 30, but the thermoset epoxy resin is hardened over the entire inner wall surface. Therefore, the mold release operation is difficult, and if you try to force the mold release, a part of the corner of the cured resin that is part of the molded core coil assembly may be chipped.

In the case of mass production, it is necessary to prepare a considerable number of molds and molds (base plates and formworks), and they also require extensive maintenance.

Because the mold release agent is baked onto the surface of the mold, the product surface may not have a good finish and may be accompanied by discoloration.

[Means for Solving the Problems] The goals to be achieved in order to solve the above problems are as follows: ■) Eliminate the work of removing the product from the mold after the thermosetting resin has hardened.

2) Preventing damage to the molded resin surrounding the product when the product is removed from the mold.

3) Eliminate molds in response to mass production.

4) Make the surface appearance of the cured resin beautiful and prevent discoloration.

5) Improve the accuracy of the resin thickness in the product gap.

In order to achieve the above goals, we prepared a plastic rectangular box-shaped container with an eave (hereinafter referred to as a box-shaped container) as an alternative to the conventional mold (formwork and base plate), and The core/coil semi-finished product with conductor wire wrapped around the core is housed in the
The box-shaped container is made into an injection mold and a thermosetting resin is injected into the core/coil assembly product, which firmly integrates the core/coil semi-finished product, the hardened resin, and the king of outsert box-shaped cases. The problem was solved by doing this.

[Function 1] A plastic box-shaped container is made into an injection mold, and with the core and coil semi-finished products housed in it, a thermosetting resin is injected, the whole is thermosetted, and the three are integrated. The plastic resin used as the injection mold is left as is as an outsert as part of the product and becomes the outer shell of the core coil assembly.

〔Example〕

FIG. 1 is a perspective view of a box-shaped container with an eave used as an injection mold for resin casting of the present invention.

Reference numeral 11 indicates the entire box-like container, 12 is a longitudinal side wall, 13 is a short side wall, and 14 is a bottom wall.

Box-shaped containers made of plastic materials used for core coil assemblies used in OA type equipment, etc. have a thickness of 0.5 m.
It can be relatively easily molded by using a sheet of about 1.5 m in size using a method such as a heat press.

FIG. 2 is a side cross-sectional view of the core-coil assembly in the completed state, in which a coil 21 is wound around the core inside the box-shaped container 11, and a thermosulfont (not shown) is attached. After storing the core/coil semi-finished products 22 with their legs 23 facing up, a thermosetting resin 24 such as epoxy resin is injected and thermoset to form a product in which the container and the core/coil semi-finished products are integrated. A core coil assembly 20 is shown.

The injected thermosetting resin 24 fills the recess of the semi-finished product with the coil wound around the core and the gap between it and the container, is post-cured, and is firmly bonded to the half-finished product.

Reference numeral 25 is a recess that accommodates the protrusion of the coil.

[Effects] In the core coil assembly of the present invention, the coil-wound member as a semi-finished product and the thermoplastic plastic container as an outsert are integrally bonded with a thermosetting resin such as an epoxy resin to form a product. Therefore, the following effects are achieved.

l) There is no need to prepare a mold for injection or manage the mold.

2) Furthermore, since the box-shaped container used in the present invention is integrated as an outsert and does not require mold release, heating work for applying a mold release agent can be omitted, contributing to cost reduction.

3) In the case of conventional methods, even if a mold release agent is applied, it is inevitable that part of the cured resin will be damaged, surface roughness, irregular discoloration, etc. will occur during mold release, but the present invention eliminates these defects. released, the uniform outer surface of the container itself becomes the surface of the product,
It has a good appearance and the color tone can be freely selected.

4) The box-shaped container that forms the injection mold and the outer shell of the product is suitable for mass production because it can be easily molded from a thin plastic sheet using a heat press or the like.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a plastic box-like container used in the present invention, and FIG. 2 is a core-coil assembly of the present invention housed in the box-like container and integrally bonded to the container with a hardened resin. Fig. 3 is a schematic side sectional view of the mold and base used in the prior art.
4: Bottom wall, 20: Core coil assembly, 21: Coil,
22: Core foot, 24: Cured resin, 25: Recess, 30: Mold, 31:
Long side wall, 32: Short side wall, 35: Base. Figure 1

Claims (1)

[Claims] 1. A plastic box-shaped container with a bottom that has side walls and a bottom wall and is open only on the top surface, and a box-shaped container with a bottom that has a core on top and a coil on the bottom. The housed core coil semi-finished product is injected into the box-shaped container with a bottom and then heat-cured to fill the recesses and voids between the container and the semi-finished product, as well as within the semi-finished product itself, and are firmly bonded. A core coil assembly for a linear motor, characterized in that the box-shaped container is fitted over the semi-finished product and integrally molded. 2. A plastic box-shaped container with a bottom, which has a rectangular cross section when viewed from above, has four side walls and a bottom wall, can completely accommodate the coil part of the core/coil semi-finished product, and is open only at the top. The core and coil semi-finished products of the linear motor are placed in the container with the core facing upward, and heat is applied to the recesses and voids existing between the inner wall of the container and the core and coil semi-finished products and in the semi-finished products themselves. A curable resin is injected, heated to a predetermined temperature to cure, and the case is inserted around the outer periphery of the coil/core semi-finished product and molded into one piece, thereby producing a core/coil assembly product. A molding method for a linear motor core/coil assembly. 3. The molding method according to claim 2, wherein the box-shaped container is a core/coil assembly for a linear motor, wherein a plastic sheet having a thickness of approximately 0.5 mm is molded using a heat press or the like. Three-dimensional molding method.