JPS60234810A - Casting mold - Google Patents

Abstract

PURPOSE:To improve remarkably workability in assembling and demounting molds by a method wherein the material larger in thermal expansion ratio than mold material is used in assembling mold parts etc. to assemble the mold parts or demount the mold automatically by the use of temperature change of the material. CONSTITUTION:The jig 12 for top and bottom forces is made of material having thermal expansion ratio larger than the linear expansion ratio of the top and the bottom mold. A cup fixing jig 15 also is made of material larger in thermal expansion ratio than the top force 2 and a cup fixing piece 14. When the jig 12 for the top and the bottom force is expanded remarkably by preheat, the top and the bottom force 2, 1 are clamped to each other and assembled so that synthetic resin does not leak from between them. The injection cup 4 also is set by the fixing jig 15 in the same way as stated above. If the forces 1, 2 are cooled all over the surface the fixing jig 12 for the top and the bottom force and the cup fixing jig 15 return to the original configurations and dimensions and the top and the bottom force 2, 1 and the injector hole cup 4 can be automatically demounted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a casting mold for impregnating insulation of electrical products, electrical windings, etc. with a synthetic resin.

[Prior art]

Conventionally, there has been a device of this type as shown in FIG.

In the figure, 1 is an electrical component, etc. (in this example, a stator)
a lower casting mold (hereinafter referred to as the lower mold) for impregnating a synthetic resin for insulation; 2 an upper casting mold (hereinafter referred to as the upper mold) to be assembled to the lower mold 1; 3 is an assembly bolt that passes through the ears 1a, 2a of the lower mold 1 and upper mold 2 and is used to assemble both molds 1, 2, and 4 stores liquid synthetic resin for insulation before injection. Inlet cup, 5 is a mounting screw for attaching this inlet cup 4 to the upper mold 2, 6 is a synthetic resin inflow groove, 7 is a stator core, 8 is a coil attached to this core 7, 9 is a side plate, 1o is an O ring inserted between the lower mold 1 and the upper mold 2.

Next, the operation will be explained.

After aligning the ears 1ae2a of the upper and lower molds 2 and 1 with the stator,
Assemble the upper and lower molds 2 and 1 using the mounting bolts 3. Thereafter, the injection cup 4 is similarly attached to the upper mold 2 with bolts 5. Next, the entire molds 1 and 2 assembled to the stator are placed in a vacuum tank (not shown), and after maintaining the atmospheric pressure in the range of 1 to 3 mHf, the molds 1 and 2 assembled to the stator are placed in a vacuum tank (not shown), and then a material such as pulp is inserted from outside the vacuum tank. Insulating synthetic resin is supplied to the injection port cup 4. The supplied synthetic resin is impregnated into the coil 8 from the synthetic resin inlet groove 6, but at this time, since it is in a vacuum state, the air inside the coil 8 is discharged, and the synthetic resin impregnated into the coil 8 is bubbled. Mixing is prevented.

Thereafter, the entire molds 1 and 2 are removed from the vacuum tank and placed in a heating furnace (not shown), where the liquid synthetic resin is heated and polymerized to solidify it. Then, by removing the assembly bolts 3 of the upper and lower molds 2 and 1 and dismantling the upper and lower molds 2 and 1, the coil 8 is covered with synthetic resin and the coil 8 in the core 7 is also filled. , the core 7, the coil 8, and the coils 8 are integrated.

Conventional casting molds are constructed as described above, so it is necessary to assemble the molds using bolts, etc., and the inlet cup is similarly attached to the mold with bolts, etc. The drawback was that workability was extremely poor and efficient work could not be performed.

[Summary of the invention]

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional method, and it uses a member with a large coefficient of thermal expansion than the mold for assembling the molds together, fixing the inlet cup, etc. The purpose of the present invention is to provide a casting mold that dramatically improves the work efficiency of assembling and disassembling molds, etc.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
In FIGS. 2 to 4, the same or equivalent parts as in the figures are indicated by the same reference numerals, 11 is a positioning bin, 12 is a second
As shown in FIG. 3, the ears la of the upper and lower molds 2, 1
The upper and lower mold mounting jigs are attached to the upper and lower molds 2a, and are made of a material having a coefficient of thermal expansion larger than that of the upper and lower molds 2 and 1. For example, when the upper and lower molds 2, 1 are made of metal such as iron, plastics with a higher coefficient of thermal expansion are used, and the upper and lower molds 2, 1 are made of metal through the head 13a of the fixing piece 130 by preheating. It is designed to exert a tightening force that prevents the synthetic resin from leaking when tightened. 14 is a cup fixing piece provided integrally with the upper mold 2, as shown in FIGS. The inserted cup fixing jig is made of a material having a coefficient of thermal expansion larger than that of the upper mold 2 and the cup fixing piece 14.

By applying preheating, the inlet cup 4 is fixedly fastened to the cup fixing piece 14.

Next, the operation of this invention will be explained.

First, after aligning the positioning pins 11, the upper and lower mold mounting jigs 12, which have a higher coefficient of thermal expansion than the upper and lower molds 2#1, are engaged with the ears 1a e 2a, as shown in FIG. A cup fixing jig 15 having a large coefficient of thermal expansion is also inserted into the inlet cup 4 as shown in the fourth figure. After that, preheating is usually applied to improve the flow of the synthetic resin. Due to this preheating, the upper and lower mold jigs 12 undergo large thermal expansion, and the upper and lower mold jigs 2,
1. Tighten them together and assemble them so that the synthetic resin does not leak between them.

The inlet cup 4 is similarly attached using a cup fixing jig 15.

Thereafter, as in the conventional case, it is placed in a vacuum tank and a heating furnace, the synthetic resin is cured, and the insulation work of the coil 8 and the like is completed.

After insulating the coil 8 and other predetermined parts using synthetic resin, if the entire molds 1 and 2 are cooled, the upper and lower mold mounting jigs 12 and the cup mounting jigs 15 will return to their original shapes and dimensions. When returned, the upper and lower molds 2°1 and the inlet cup 4 can be automatically dismantled.

Furthermore, although the above embodiment describes the case of insulating a stator, it can also be applied to insulating other general electric components, and the same effects as in the above embodiment can be achieved.

〔Effect of the invention〕

As described above, according to the present invention, a material having a higher coefficient of thermal expansion than the mold is used to attach the mold parts, so that the assembly and disassembly of the mold parts can be performed automatically by changing the temperature. Since it can be carried out quickly, the workability of assembling and disassembling the mold is dramatically improved, and the work can be carried out more efficiently.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of a conventional device, Fig. 2 is a longitudinal sectional view of an embodiment of the present invention, Fig. 3 is an enlarged perspective view of the mold attachment part, and Fig. 4 is an enlarged view of the inlet cup attachment part. A perspective view is shown. DESCRIPTION OF SYMBOLS 1... Upper mold, 2... Upper mold, 4... Inlet cup, 12... Upper and lower mold fixing jig, 15... Inlet cup fixing jig. Patent applicant Mitsubishi Electric Corporation Representative Patent attorney 1) Hiroshi Sawa (2 others)

Claims (1)

[Claims] In a casting mold for impregnating electrical parts, electric machine windings, etc. with a synthetic resin for insulation, the assembly part of the casting mold is made of a material with a higher coefficient of thermal expansion than the casting mold. Characteristic casting mold.