JPH0338770Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Technical Field> The present invention relates to an improvement of an integrally molded power plug.

<Prior art> Conventional general one-piece plugs are usually made of soft vinyl chloride, etc., but they can generate abnormal heat due to poor contact, especially when they are not properly fitted with an outlet. In this case, the material on the outlet side is made of a material with good heat resistance such as phenol or urea, so the vinyl chloride of the power plug will start to carbonize first, and eventually the insulating part between the plug blades will carbonize. Do not use an integrally molded vinyl chloride power plug for equipment with a high rated current and long operation time, as this may cause a current leak and cause an accident resulting in smoke and fire. was not desirable.

Therefore, as a method to improve the heat resistance performance of power plugs, the insulating wall between the attachment part of the plug blade and the plug blade is constructed of a base molded from a resin (for example, phenol, urea, polyamide, etc.) that has better heat resistance than vinyl chloride. A power plug whose outer periphery is integrally molded with conventional flexible resin (vinyl chloride) has been devised and put into practical use.

This power plug has a structure as shown in FIGS. 1 and 2.

That is, 1 is a plug body made of a flexible synthetic resin material, and a cord protector 3 for improving the bending characteristics of the power plug 2 is integrally molded therein.
4 is a base molded from a synthetic resin material with better heat resistance than the plug body 1, and a partition wall 6 is formed at the center of the upper surface for partitioning a plurality of plug blades 5, 5 on both sides, The above-mentioned plug blades 5, 5 are attached to the base body 4 so as to sandwich this partition wall 6.

The conventional power plugs described above are improved in terms of heat resistance and safety compared to power plugs molded only from soft vinyl chloride, but the plug blades 5, 5 and the plug blades 5, 5 and the power Since the connecting part A of the cord 2 has a part that is in close contact with vinyl chloride, if abnormal heat generation occurs due to poor contact between the plug and the outlet as described above, the plug blades 5 and 5
and connection part A between outlets 5, 5 and power cord 2
There was a problem in that the heat was transmitted to the parts of the product, causing the soft vinyl chloride in those parts to deteriorate.

Moreover, the power plug as described above is molded by integrally molding the periphery of the base with a flexible resin material, but when performing this resin molding, the high temperature resin material is exposed to the connection part A. Since the connecting portion A is in direct contact with the plug, the connecting portion A is eroded by heat, which hastened the deterioration of the connecting portion between the plug blade and the power cord.

In order to eliminate the influence of heat during molding on this connection part A as much as possible, it is sufficient to completely cover this connection part A with a base made of a heat-resistant material, but heat-resistant resin materials are If the base body is not very flexible and has an insertion hole that is in close contact with the connection part A to prevent the flexible resin from entering the connection part A during integral molding, it is impossible to insert the plug blade into the base body, let alone the connection part A mentioned above. It is expected that it will be difficult to do so.

<Purpose> The purpose of the present invention is to improve the heat resistance of the connecting portion between the power cord and the plug blade, and to provide a power plug that is easy to manufacture.

For this purpose, the present invention fixes each plug blade individually with a base made of a heat-resistant material, and this base is composed of an upper member and a lower member, and the upper member and the lower member are connected to each other. A concave clamping part is provided on the joint surface with the member to fit the end of the power cord connection side of the plug blade and the end of the power cord on the power cord connection side, and the upper member and the lower member of the base The end of the power cord connection side of the plug blade and the plug blade connection portion of the power cord are respectively held between the above-mentioned clamping portions, and the periphery of this base body is covered with a flexible resin material and integrated. It is molded.

As a result, the connecting part between the plug blade and the power cord is surrounded by a base made of a heat-resistant material, and this base prevents contact between the flexible resin and the plug blade and the connecting part. completely prevent it.

In this case, the base body is composed of an upper member and a lower member, and the joint surface of the upper member and the lower member includes the end of the power cord connecting side of the power cord and the end of the power cord connecting side of the power cord. A concave clamping part into which the ends fit is provided, and the clamping part is used to fit the end of the power cord connection side of the plug blade and the plug blade of the power cord, respectively, between the upper member and the lower member of the base body. Since the connecting end is clamped, the connecting part between the plug blade and the power cord can be easily completely surrounded by heat-resistant resin material by simply sandwiching the connecting part between the above-mentioned plug blade and the power cord between the clamping parts of the above-mentioned vertically divided base. .

Moreover, since the base body is provided individually for each blade, the work of sandwiching the connection portion to the base body can be performed for each blade individually, making the work relatively simple.

After the flexible resin is integrally molded, the flexible resin surrounds each individually provided base, so that the resin does not peel off at the boundary between the base and the flexible resin.

<Embodiment> An embodiment of the present invention will be described below with reference to FIGS. 3 to 6.

That is, as shown in Fig. 3, 11 is a plug body made of flexible synthetic resin material, and a power cord 1
The cord protector 13 is integrally molded with the cord protector 13 for improving the bending characteristics of the cord protector 2. 1
4 and 14 are a pair of bases made of a material with better heat resistance than the plug body 11;
Plug blades 15, 15 are respectively clamped to the plug body 14, and a flexible synthetic resin material integral with the plug body 11 is filled between the base bodies 14, 14. Base 1
4 and 14 have a two-part structure, each consisting of a lower member 16a and an upper member 16b, as shown in FIG. The clamping part 18a of
is formed, and a locking protrusion 19a is formed in the clamping portion 18a.
A plurality of engagement protrusions 20a are provided on the peripheral edge, and the upper member 16b has a stepped portion 17b and a clamping portion 18b formed in the same manner as the lower member 16a, and each protrusion 1
A locking hole 19b and an engaging hole 20b are bored so as to face the holes 9a and 20a.

As shown in FIG.
are passed through the engagement protrusions 19a of the lower member 16a, and the plug blade 15 is placed on the clamping part 18a, and each protrusion 19
A and 20a are fitted into the locking hole 19b and the engagement hole 20b of the upper member 16b, and the plug blade 15 is attached to the lower member 1.
6a and the upper member 16b.

Next, to explain the manufacturing procedure of the power plug of the present invention, the base 14, which has the plug blade 15 with the power cord 12 connected between the top and bottom of the mold, is placed so that the bottom surface is placed on the top surface under the mold. The power plug of the present invention is formed by placing the molds in close contact with each other and injecting a flexible synthetic resin material, and after the synthetic resin material hardens, separating the upper and lower parts of the mold. Note that the power plug of the present invention is not limited to the shape described in the above embodiments, and the shape of the base body may be set depending on the shape of the power plug body and the shape of the plug blade.

As described above, according to the present invention, each plug blade is individually fixed to a base made of a heat-resistant material, and this base is composed of an upper member and a lower member, and the upper member and the lower member are connected to each other. A concave clamping part is provided on the joint surface with the member to fit the end of the power cord connection side of the plug blade and the end of the power cord on the power cord connection side, and the upper member and the lower member of the base The end of the power cord connection side of the plug blade and the end of the power cord connection side of the power cord are held between them using the above-mentioned clamping parts, and the periphery of this base body is covered with a flexible resin material. By integrally molding, the base body completely prevents contact between the flexible resin and the plug blade or the connecting part between the plug blade and the power cord, so the connecting part is not exposed to high temperature when molding the power plug. By completely eliminating contact between the resin materials, it is possible to completely prevent the connection portion from deteriorating due to heat. In addition, after the power plug is molded, even if heat is applied to the plug blade for some reason, the heat at the connection part will not be transferred to the flexible resin material at all, and the flexible resin material will carbonize. It is possible to eliminate accidents caused by burnout.

In the case of this invention, in order to completely surround the above-mentioned plug blade and connecting portion with a base made of a heat-resistant material, the base is divided into upper and lower members, and a concave shape is formed on the joint surface of these members. This can be done simply by providing a clamping part and sandwiching the clamping part between the upper and lower members, which eliminates the conventional method of fixing the blade to the base by inserting the blade into a hole in the base. The connecting portion can be completely surrounded by a heat-resistant resin material very easily compared to the conventional plug, and because of this ease of manufacture, the manufacturing of the power plug can be easily automated.

In addition, since the base body is provided individually for each plug blade, the work of attaching the base body to the plug blade and the connecting part is relatively easy, and this, combined with the fact that the base body is divided into upper and lower parts, simplifies the process of assembling the power plug. It can be done easily.

Furthermore, by providing a base for each plug blade, the flexible resin surrounds each base after integral molding with the flexible resin, making it difficult for the resin to peel off at the boundary between the base and the flexible resin. This eliminates inconveniences such as leakage caused by water entering the inside of the plug through this peeling.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a conventional power plug, FIG. 2 is a sectional view of the main part of FIG. 1, FIG. 3a is a perspective view of the power plug of the present invention, and FIG. 3b is a sectional view of the same main part. 4a and 4b are perspective views of the lower and upper members of the base used in the present invention, and FIG. 5 is an exploded view of the base and the blade. 11 is the power plug body, 12 is the power cord, 1
4 and 14 are base bodies, 15 and 15 are plug blades, 16a is a lower member, and 16b is an upper member, respectively.

Claims (1)

[Claims for Utility Model Registration] Each plug blade is individually fixed to a base made of a heat-resistant material, and this base is composed of an upper member and a lower member,
A concave clamping part is provided on the joining surface of the upper member and the lower member to fit the end of the power cord connection side of the power cord and the end of the power cord on the power cord connection side, and The end of the power cord connection side of the plug blade and the end of the power cord connection side of the power cord are held between the upper member and the lower member using the above-mentioned clamping parts, respectively, and the periphery of this base is covered with a flexible resin material. A power plug that is coated and molded in one piece.