JPS59189578A - Heat generator - 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 The present invention relates to a heating element that heats fluid by passing a fluid through a through hole, and particularly aims to improve the heating efficiency of fluid.

In general, barium technoate semiconductor porcelain made of BaTi09 semiconductor foil, which has a positive resistance-temperature coefficient, exhibits a rapid increase in resistance when the temperature exceeds a certain point, and conversely decreases when the temperature falls below this certain temperature. It is used as a heating element with a self-temperature control function in a heating device (ffi').In addition to having a self-temperature control function, this heating element has excellent thermal properties because it is made of porcelain. It has the characteristics of being highly reliable and inexpensive, and has high utility value.

First, a conventional heating element had a structure as shown in FIGS. 1 and 2. That is, in these figures, -C11 is a ceramic having a positive temperature coefficient of resistance (hereinafter referred to as positive characteristic porcelain) in which a through hole 2 is bored, and the through hole 2 is formed on the surface of the positive characteristic porcelain 1. 1B and 1B each have a G-RO section. 32L and 3b are surfaces 1a and 1 of positive characteristic porcelain 1
These are the electrodes for heating positive characteristic porcelain provided respectively in b.

A mechanism for heating a fluid, for example air, using such a heating element will be explained based on FIG. 3 (an enlarged view of the main part of FIG. 2). When a voltage is applied between the electrodes 3a and 3b, a 1L current 4 flows inside the porcelain 1 on the hour along the wall of the through hole 2, and J]-characteristic porcelain 1 generates heat.At the same time, the air 5 When air is blown from one opening of the through hole 2, the air 5 is heated by the positive characteristic porcelain 1 as it passes through the through hole 2, and is sent out from the other opening.The average temperature of the heated air 5 is 5, the wind speed and volume, the length e of the through hole 2 which is the air passage, and the magnitude of the voltage applied between the electrodes 3a and 3b.

It becomes rough depending on the temperature distribution state of the wall surface of the through hole 2, etc.

However, in the conventional heating element described above, the electrodes 3a and 3b
is provided at one corner of the opening side of the through hole 2 in the 11E characteristic porcelain 1, so the current 4 flows inside the positive characteristic porcelain 1 through the through hole 2.
This is a drawback in that the flow flows along the wall surface of the through hole 2, and the heat generation temperature distribution on the wall surface of the through hole 2 becomes uneven, reducing the heating efficiency for fluids such as air 5. In order to make this heat generation temperature distribution uniform, the thickness of the 1F characteristic porcelain 1 (i.e., the through hole 2
However, if the thickness of the positive characteristic porcelain 1 is made thinner, the area where the air 6 contacts the positive characteristic porcelain 1 in the through hole 2 becomes smaller, and the heating element becomes smaller. The present invention was made in order to eliminate the above-mentioned conventional drawbacks, and in order to improve the heating efficiency of the fluid passing through the through holes of positive characteristic porcelain, A heating electrode is provided on the wall of the through hole, so that current flows through the positive characteristic porcelain in a direction perpendicular to the wall of the through hole.

An embodiment of the present invention will be described in detail below with reference to the drawings. Fig. 4 is a perspective view of a heating element in an embodiment of the present invention, and Fig. 5 is a cross-sectional view (r↓the same heating element thousand whistles).In these figures, the flat positive characteristic porcelain 6 has a A plurality of through-holes 7 having a rectangular cross-sectional shape are bored, and a plurality of electrodes 8a and a plurality of negative electrodes 8b are alternately provided on the wall inside the through-holes 7. The negative electrodes 8a are electrically connected to each other and fixed to the terminal 9a, and the negative electrodes 8b are similarly electrically connected to each other and connected to the terminal 9.b[
(Terminals 9a and 9b are not drawn in FIG. 4.)

Incidentally, in order to provide an electrode in the through hole of the positive characteristic porcelain, methods such as plating, electrode stripping impregnation, vapor deposition, etc. may be used.

The case where a fluid, for example air, is heated using the heating element in the embodiment of the present invention will be considered with reference to FIG. terminal 9
When a direct pressure is applied between a and 9b (not shown in FIG. Since the positive characteristic porcelain 6 generates heat, a constant current flows per unit area on the wall surface of the through hole 7, so that the heat generation temperature distribution on the wall surface of the through hole 7 is uniform. In this state, a fluid such as air 1
When air 11 is blown from one opening of the through-hole 7, when the air 11 passes through the through-hole 7, it comes into contact with the wall surface of the through-hole, which has a uniform heat generation temperature distribution, and is heated, and is then sent out from the other opening. In the above embodiment, the electrode 8 for heating positive characteristic porcelain
Since the positive characteristic porcelain 6 is sandwiched between the electrodes a and 8b on the wall of the through hole 7, the electrodes sa, s
When a voltage is applied between b, current (d flows perpendicular to the wall surface of the through hole 2, the heat generation temperature distribution on the wall surface of the through hole 2 becomes uniform, and the heating efficiency for the air 11 passing through the through hole 2 is the same as that of the conventional one. It's about 1.5 to 2 times more efficient -1.

As explained above, the heating element of the present invention has a simple structure and can greatly increase the heating efficiency of fluid, and is of great practical value.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a conventional heating element, Fig. 2 is a sectional view of the same, Fig. 3 is a sectional plan view of the main part to explain the operation of the heating element, and Fig. 4 is an embodiment of the present invention. FIG. 5 is a plan sectional view of the heating element in the example, and FIG. 6 is a plan sectional view of the main part for explaining the operation of the heating element. 6...- Porcelain with positive resistance-temperature coefficient, 7...
...Through hole, 82L, 8b...Electrode. Name of agent Patent attorney Masao Nakao and 1 other person Figure 1 I d Figure 2 Figure 3 d b Figure 4

Claims (1)

[Claims] A heating element in which a large number of through holes are provided as fluid passages in porcelain having a positive resistance and temperature coefficient, and an electrode is provided on the inner wall of the through hole to allow a current to pass through the porcelain in a direction perpendicular to the wall surface.