JPS5830089A - Heater utilizing ptc element - 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 device using a positive temperature coefficient (PTC) element, particularly a method for configuring an electrode in a PTC element whose main components are a crystalline resin and conductive particles, and its accompanying The present invention relates to a heating device with an improved electrode extraction method.

The present invention is suitable for use as an intake air heating device for an internal combustion engine, for example.

BACKGROUND OF THE INVENTION When an internal combustion engine is running at a low temperature, the air-fuel mixture is heated to promote vaporization of the fuel and improve drivability.

As a means for this purpose, a system using a positive temperature coefficient (PTC) heating element has been developed. It is being considered that the system could be used in a cylindrical or honeycomb shape. The heating element is constructed to be incorporated into an insulator between the carburetor and the intake manifold, but there are various problems in the method of configuring the electrodes and the method of taking out the electrodes. For example, in the case of a cylindrical heating element, there are the mg method in which the electrodes on the inner and outer surfaces are drawn out at right angles to the direction of the heating element, and the method in which the electrodes are drawn out to the outside. As a method of drawing out the inner and outer surfaces of the cylinder in the h angle direction with respect to the part direction, it is considered that a 7-rat flange part is provided separately from the cylindrical part and one bottom surface of the flange part is used respectively. The conduction between them can be integrated by metal plating.The plating part is partially removed to form a pair of electrode surfaces.
&Depending on the method of taking out the electrodes from the surface to the outside, removing part of the plated part can be very complicated. For example, when an electrode terminal is squeezed into a flange portion and brought into contact with an electrode surface, insulation between a pair of electrode surfaces must be taken into consideration, resulting in a composite electrode surface that is interwoven with each other.

An object of the present invention is to provide a heating system using a PTC element that simplifies the 11-pole configuration of a PTC heating element whose main components are crystalline resin and conductive particles, and facilitates increasing the number of electrodes. That's true.

Hereinafter, embodiments of the present invention will be explained in detail with reference to the accompanying drawings.

1 and 2 show an embodiment in which the heating device of the present invention is used as an intake air heating device for an internal combustion engine.

1 is a carburetor hD, which is installed on the upper part of the intake manifold 2, and the heat insulator 3 is interposed between them, and the two are combined at the root 4. @5 and 6 are the carburetor 1 and the heat These gaskets are provided between the insulators and between the heat insulator 3 and the intake manifold F''2.

The heating device of the present invention includes ~ Tsutsubayashi's heating element 7 and this heating element 7.
It stands out from the support body that supports it, that is, the combination with the heat insulator 3. It is located downstream of the throttle box 8 of the 7/Ii carburetor (slow thread), and plays the role of guiding the mixture from the throttle box 8 to the intake manifold 2. At the same time, the tC1 The mixture is heated as it passes through.

In FIGS. 2 and 3, in order to construct the heating element 7 used in the present invention, first, a PTC heating cord 9 which is mainly composed of binding resin and conductive particles and exhibits a positive temperature coefficient is inserted into a tube. The PTC heat-generating cord 9 is formed in the form of a crystal @
After melting the resin and adding carbon black particles thereto, dispersing and mixing the mixture, this kneaded material is finely pulverized, and gasis fiber blend M (i[l!-forming polyester resin is blended into the powder). , this arrangement can also be accelerated by putting it into v/Jtl-fatigue and making it into a cylindrical shape by heat forming.゛This cylindrical PT
The C heating element 9 has a flange 1 which protrudes outward from the outer end of its axial force 10 (the upper end in FIGS. 2 and 3).
0 is integrally formed. This 7-run no. 10 may be made of the same material as the heating element 9 and integrally formed into a mH shape. In this example (Fig. 2, Fig. 3, and Fig. 4), a slightly raised part 20 in the axial direction is provided at the tip of the 7 flange 10. At the same time, a recess 21 is formed on the inner side of the raised portion 20.The raised portion s20 and the recess s21
becomes the electric & male department. In the embodiment of the present invention (FIG. 6), an axially raised portion 22 is provided at the tip of the flange 10.
This part becomes the male part of the electrode. 1. The thinner part 23 in the axial direction is broken at the tip of the flange 10, and this thinner part becomes the electrode male part. becomes.

Electrode plating layers 11 and 12 are formed on the inner and outer cylinder surfaces of the heating element 9, respectively. Figure 4.

In FIGS. 6 and 7, the electrode plating layer 11 formed on the inner cylindrical surface is applied to one surface of the male electrode part (i.e., one surface 20 & of the raised portion 2o in FIG.
In FIG. 6, one surface 22a of the channel raised portion 22 extends to one surface 23a) of the thinned portion 23 in FIG. In addition, electrode plating formed on the outer cylinder surface yi#
12 is the other surface of the male electrode part from the upper surface of the flange 10 (that is, the other surface 2ob of the raised portion 20 in FIG. 4, the other surface 22b of the raised portion 22 in FIG. 6, and the smaller wall thickness in FIG. 7). It extends to the other surface 23b) of the portion 23 that has become. These electrode plating layers 11 and 12 are not in contact with each other, and are separated from each other by at least a certain distance (usually the thickness of the heating element 9).

In order to actually form the electroplated layer 11.12, after plating the entire part including the cylindrical heating element 9 and the flange 10, the end face 24 of the cylindrical part opposite to the flange 10, The peripheral side surface 25 of the flange 10 and the end surface of the male electrode part of the seventh flange 10 (i.e., the end surface 20a in FIG. 4)
, the inner surface of the end surface 22C in FIG. 6 and the end surface 23c in FIG.
゜12 are made independent from each other.

Next, the secondary heating element 7 formed in this manner is assembled into the heat insulator 3, which is a support (FIG. 3). For this purpose, a hole 15 for receiving the cylindrical portion of the heating element 7 and a recess 14 for receiving the 7 flange 10 are formed in the heat insulation 3. In the recess 14, when the heating element 7 is assembled, the electrode male portion of the electrode male portion formed on the flange 10 is inserted.

Electrode plates made of a spring metal are provided that contact each of the two layers, and these electrode plates constitute a female electrode part that fits into a male electrode part. In the first embodiment shown in FIG. 4 or the second embodiment shown in FIG. 6, the electrode plate 1 as shown in FIG.
6m, 16b can be used and these electrode plates 161
．． 16b are lead wires 17m and 17b, respectively (Figure 3)
The lead wires 17m and 17b are connected to the small hole 18m,
The electrode plates 16a and 16b are fixed in a predetermined position in the recess 14 by being pulled out from the electrode plate 18b. Therefore, when the heating element 7 is assembled into the heat insulator 3, the electrode plates 16m and 16b, which are female electrodes, are elastically deformed, and the male electrode parts (20m, 20b; 22m) of the heating element are elastically deformed.

22b:, 23m, 23b) is ensured. After installing the heating element 7, the heat insulator 3 is inserted between the vaporizer 1 and the intake manifold 2' with the gasket 5.6 in between, and is fastened by the bolt 4. Note that the material and number of electrode plates 16m and 16b made of spring metal are determined in consideration of current value and contact pressure.

When such a heating device of the present invention is used as an intake air heating device for an internal combustion engine, when the intake air temperature is low, such as during a cold start, the electric resistance value of the PTC element 9 is small, so a large current flows and heats up. , heating of the intake air passing through this takes place. When the intake air temperature becomes high enough, the electrical resistance value of the PTC element 9 becomes large and current substantially stops flowing, so that heat generation is stopped.

As described above, according to the heating device of the present invention, electrodes can be formed into I/III easily by removing the plating on the required portions of the heating element 7, and the electrodes can be easily removed. It has the advantage of being easy to perform and requiring fewer parts and fewer man-hours.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of the intake system of an internal combustion engine, and Fig. 2 is an enlarged cross-sectional view taken along the line ■-■ in Fig. 1, showing a state in which the heating device of the present invention is used in the intake air heating device of an internal combustion engine. something that shows
Fig. 3 is an exploded perspective view of the heating element of the heating device of the present invention when it is assembled, Fig. 4 is a perspective view of the first embodiment of the heat generating element used in the invention, and Fig. 5 is an exploded perspective view of the electrode plate used in the invention. Perspective view, No. 6
The figure is a perspective view of a second embodiment of the heating element, and FIG. 7 is a perspective view of a third embodiment of the heating element. 3... Support (heat insulator), 7... Heating element, 9... PTC element, lO... Flange, 11
゜12... Electrode plating layer, 16 a * l 5 b
*-Electrode female part (electrode plate), 20m, 20b: 22
m, 22b; 23a, 23b...male electrode part. Patent Applicant: Toyota Motor Corporation, Matsushita Electric Industrial Co., Ltd., Patent Application Representative, Patent Attorney: Akira Aoki, Patent Attorney, Kazuyuki Nishidate, Patent Attorney, Soto Higuchi, Patent Attorney, Akira Yamaguchi, Patent Attorney, Figure 1, Figure 2, No. 31, No. 41 Figure 5 Associate Figure 7

Claims (1)

[Claims] 1. A heating element mainly composed of crystalline resin and conductive particles and exhibiting a positive temperature coefficient is formed into a cylindrical shape, and seven flange protruding outward from the axial direction of the cylindrical heating element is provided. , at least a portion of the flange is formed as a male crowned portion, and each electrode layer formed on the cylindrical surface and the outer cylindrical surface of the cylindrical heating element is extended to the male portion of the flange so as not to contact each other. and without electrode male part,
A heating device using a PTC element, characterized in that a heat insulator supporting the heating element thus formed is provided with a female electrode part made of a metal plate that fits with the male electrode part.