JPH0127595Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an embedded heating element used in hot plates, coffee makers, etc.

Structure of conventional example and its problems As shown in Figs. 1 to 3, the embedded heating element used in conventional hot plates, coffee makers, etc. A heating wire 3 is buried in the center of the concave groove 2 with insulating powder 4, and electrical wiring is provided at both ends of the heating wire 3 so that electricity can be applied to the heating wire 3. It had a structure in which the terminal 5 was fixed and a part 5a of the terminal 5 was exposed from the insulating powder 3. However, in this structure, if the width of the groove 2 is narrow as shown in FIG.
Since the distance between the terminal 5 and the groove wall 2a becomes short, the exposed part 5a of the terminal 5 and the groove wall 2a may become attached due to adhesion of water droplets, etc.
Therefore, as shown in FIG. 3, conventionally, as shown in FIG.
Generally, b is provided. However, in such a configuration, the length of the embedded side of the terminal 5 is shorter than the widened part 2b of the groove 2 for embedding the heating wire, so that the connection between the heating wire 3 and the terminal 5 is difficult. As a result, the heat generated from the heating wire 3 in the vicinity of the joint is transferred over the conduction distance of the insulating powder 4 made of an inorganic material or the like with poor thermal conductivity. Due to the long length of the insulating powder 4, it is not absorbed into the groove wall 2a and abnormal heat generation occurs in that part, resulting in thermal deterioration of the insulating powder 4 and the insulating performance cannot be ensured. In addition, there is a further problem in that the heating wire 3 is broken due to abnormal heat generation, making it unusable.

Purpose of the invention The present invention solves the above-mentioned conventional problems, and aims to provide an embedded heating element that is safe and has a long life by improving the durability of the insulating powder and heating wire. It is something.

Structure of the invention In order to achieve the above object, the embedded heating element of the invention has a recessed groove for embedding a heating wire in which a part of the groove width at both ends is wider than the other part, and a central part of this recessed groove. It has a heating wire arranged, a terminal fixedly connected to both ends of the heating wire, and an insulating powder for embedding the heating wire and the terminal in a groove, and one side of the embedding side of the terminal. The part is made longer than the wider part of the recessed groove for embedding the heating wire, and is fixedly connected to the heating wire at the narrow part of the groove. According to this configuration, the heating wire is
The wire is always buried in the narrow part of the groove, and as a result, the heat generated by the heating wire is easily absorbed by the groove wall due to the short conduction distance with the groove wall, which has good thermal conductivity. , localized abnormal fever will no longer occur. This also eliminates deterioration of the insulating powder, making it possible to always ensure stable insulation performance and also eliminate disconnection of heating wires.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. In Figures 4 and 5,
Reference numeral 11 denotes a groove for embedding a heating wire provided on the back surface of the electrical equipment 12; 13 indicates a heating wire disposed in the center of the groove 11; The terminals 14 are fixedly connected so that electricity can be supplied to the terminals 14. 15 is an insulating powder for embedding the heating wire 13 and the terminal 14 in the groove 11, and 11a is an insulating powder for embedding the heating wire 13 and the terminal 14 in the groove 11; Part 11
A part 14a on the embedded side of the terminal 14 in a part wider than b is made longer than the part 11a where the groove width is widened, and is fixedly connected to the heating wire 13 at a part 11b with a narrow groove width. . Therefore, heating wire 13
is always buried in the narrow part 11b of the groove, and as a result, the conduction distance with the groove wall, which has good thermal conductivity, is short, so the heat generated from the heating wire 13 is easily transferred to the groove wall. Therefore, localized abnormal heat generation will not occur, and deterioration of the insulating powder 15 and disconnection of the heating wire 13 will also be eliminated.

Effects of the invention As described above, in the embedded heating element of the invention, the part on the embedded side of the terminal is made longer than the part where the groove width is widened at both ends of the recessed groove for embedding the heating wire. Because the narrow part of the groove is firmly connected to the heating wire,
This eliminates the possibility of localized abnormal heat generation of the heating wire, and therefore prevents insulation breakdown due to deterioration of the insulating powder and a decrease in the durability of the heating wire.As a result, safety and durability are improved. This is something that can improve performance.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of an electrical device that uses a conventional embedded heating element, Figure 2 is an enlarged view of the same terminal, Figure 3 is an enlarged view of another example of the same terminal, and Figure 4 FIG. 5 is a sectional view of an electrical device employing an embedded heating element, showing an embodiment of the present invention, and FIG. 5 is an enlarged view of the terminal portion thereof. DESCRIPTION OF SYMBOLS 11... Concave groove for embedding heating wire, 11a... Portion with widened groove width, 11b... Portion with narrowed groove width, 13... Heat generating wire, 14... Terminal, 14a...
Part of the embedded side of the terminal, 15...Insulating powder.

Claims (1)

[Scope of utility model registration request] A concave groove for embedding a heating wire with a part of the groove width at both ends wider than other parts, a heating wire disposed in the center of this groove, and a heating wire fixedly connected to both ends of the heating wire. A terminal, and an insulating powder for embedding the heating wire and the terminal in a groove, and a part of the embedding side of the terminal,
An embedded type heating element in which the width of the recessed groove for embedding the heating wire is made longer than the wide part, and the narrow part of the groove is fixedly connected to the heating wire.