JPS62262401A - Ptc thermistor device and manufacture of the same - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a surface heating type thermistor, and particularly to the shape of a positive characteristic thermistor (PTC) element and its manufacturing method.

[Prior art]

Conventional surface heating type thermistors (PTC) are shown in Figures 6 and 7.
As shown in the figure, comb-shaped electrodes were formed facing each other on the surface of the element, and terminal extensions connected to these electrodes and extending from both sides of the element to both ends of the back surface were provided. However, no matter how the electrode is formed, it requires multiple steps, increases production costs, and has poor productivity.In addition, when using the conventional surface Since the heat-generating thermistor (PTC) has a heat-generating surface in contact with a heat-transfer surface through an electrode, heat dissipation is poor and the heat dissipation varies, making stable operation impossible.

[Problem that the invention attempts to solve]

The present invention provides a surface heating type PTC thermistor that facilitates the formation of comb-shaped electrodes, provides a highly productive element shape, and provides stable operation, as well as a method for manufacturing the element.

[Means for solving problems]

As shown in FIG. 1, in the present invention, comb-shaped electrode grooves 3 formed in concave shapes are provided on the front side 1 of the element main body to face each other, and the back side 2
Terminal lead-out stepped portions 4 are formed at both ends, and these are integrally press-molded with the element body. and,
This integrally molded element is made into fired porcelain, a thin film electrode is formed on the outer surface of the element, and the front and back surfaces 1.2 of the element and the side surface 5.5 parallel to the electrode groove 3 are ground to obtain an internuclear space of 1.2.5. A PTC thermistor element is manufactured by removing the electrode thin film.

[For production]

Since the PTC thermistor element is shaped as shown in Figure 1, when forming a thin film electrode thereon, the thin film electrode is first formed on the outer surface of the element, and then the front and back surfaces of the element and the side surfaces parallel to the electrode groove are ground. By doing so, the electrode thin film on the surface is removed, and the front and back surfaces and side surfaces are made parallel and flat, and a device with uniform shape and stable operation is manufactured.

〔Example〕

Figures 1 to 5 show an embodiment of the present invention.
The C thermistor element main body has comb-shaped electrode grooves 3 formed in a concave shape facing each other on the front side 1, and terminal lead-out stepped portions 4, 4 are formed on both ends of the back side 2, which are made of various compounds. The element body is constructed by integral press molding, then fired into porcelain, and then subjected to barrel polishing as necessary to round each edge. This reduces the possibility that a portion of the edge portion may be missing due to a collision of the device during work or transportation of the device.

Next, a thin film electrode is formed on the entire outer surface of the element by means such as N+ electroless plating, Ni electroless + electrolytic plating, Ni electroless ten Ag baking plating, sputtering, and thermal spraying. The front and back surfaces 1.2 and the side surfaces 5.5 parallel to the electrode grooves 3 are ground with a surface grinder or surface lapping machine to remove unnecessary electrode thin films, and the parallel flatness of the front and back surfaces and the side surfaces 5, 5 is adjusted. produced. In order to manufacture an element like the one shown in Figure 1, it is necessary to press-form a long piece in the horizontal direction, form a thin film electrode on it, grind only the front and back surfaces, and finally cut it at appropriate intervals. A large quantity of elements of many types can be produced, and since grinding of the side surfaces is not required, mass production can be carried out at low cost. Further, when forming a thin film electrode, if measures are taken to prevent electrodes from being formed on the side surfaces 5.degree. 5, the grinding of the side surfaces 5, 5 can be omitted.

〔Effect of the invention〕

As described above, since the surface heating type PTC thermistoric element of the present invention has the shape as shown in FIG. 1, it is easy to form a thin film electrode, and it can be mass-produced at low cost. Furthermore, since the front and back surfaces are ground to provide parallel flatness, the heat generating surface can be mounted in perfect contact with the heat transfer surface, and the operation of the element can be stabilized.

[Brief explanation of drawings]

Figures 1 to 5 show an embodiment of the present invention, with Figure 1 being a perspective view, Figure 2 being a front side plan view, Figure 3 being a back side plan view, and Figure 4 being a back side plan view.
The figure is a sectional view taken along the line A-A in Figure 3, and Figure 5 is a side view of Figure 3.
FIG. 6 is a perspective view showing a conventional example, and FIG. 7 is a sectional view of FIG. 6 with the use surface facing downward. 1... Front side, 2... Back side, 3... Electrode groove, 4
...Step part, 5...Side surface.

Claims (2)

[Claims] (1) Concave comb-shaped electrode grooves are provided on the front side of the element body to face each other, and terminal lead-out stepped portions are formed on both ends of the back side, and these are integrally molded. P
TC thermistor element. (2) Concave comb-shaped electrode grooves are provided facing each other on the front side of the element body, and terminal lead-out stepped portions are formed at both ends of the back side, which are integrally press-molded with the element body. A method for manufacturing a PTC thermistor element, which comprises firing a PTC thermistor element into porcelain, forming a thin film electrode on the outer surface of the element, and grinding the front and back surfaces of the element and side surfaces parallel to the electrode grooves to remove the electrode thin film on the surfaces. .