JPS606060A - Heating device - Google Patents

Abstract

PURPOSE:To simplify solid structure of a heater and to prevent damage of an engine during breakage through prevention of the occurrence of over heat, by a method wherein a heater having a self-current control function is held between the nip formed by a pair of terminal members. CONSTITUTION:Through application of a voltage between feeders 11 and 12 of a heater 6, a current flows between a pair of terminal members 7 and 8, and the heater 6 is self-heat-generated. The heat is transferred to a radiation part 7d through an annular part 7a of the terminal member 7 to heat air-fuel mixture passing through the inner side of the radiation part 7d. Thus, the solid structure is extremely simplified, and since the heater has self-current control function, there is no fear of over heat occurring, and an engine is prevented from damage due to admission of fragments, into which a heat-generating material is broken, into a combustion chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heating device that is conveniently applied to, for example, an intake air heating device for promoting vaporization of fuel in an internal combustion engine IM+.

Conventional heating devices of this type are equipped with heaters that have a self-current control function, such as those made of barium titanate-based ceramic semiconductors that have a positive temperature coefficient of resistance. It requires a large number of parts to construct, which makes the structure complex and increases the number of assembly steps.

In addition, the conventional tJsP4108125, U.S.P.
In the one disclosed in No. 4,141,327, there is no guarantee that the heating element will not break, and therefore, if the heating element breaks, fragments may enter the combustion chamber and cause damage to the engine.

The present invention aims to provide a heating device that eliminates the above-mentioned problems.

Hereinafter, the present invention will be applied to an intake air heating device for an internal combustion engine.

Examples will be described in detail. FIG. 1 is a sectional view showing the intake system of an internal combustion engine. 8 device 3 is fixed via its heat-resistant electrical insulator 9. Note that the intake air heating device 3 is located downstream of the throttle f4.

Next, the detailed structure of the intake air heating bag W3 will be explained. In FIGS. 2 to 12, the heater 6 is made by molding and sintering a barium titanate-based positive temperature ceramic semiconductor material into a ring shape, and has thin film electrodes (not shown) on the front and back surfaces of the heater 6. It is formed. This heater 6 is sandwiched between the front and back surfaces by a pair of terminal members 7.8.

In this pair of terminal members 7.8, one terminal member 7 is constituted by a ring-shaped portion 7a1, a connection all 71) fixed by welding to the ring-shaped portion 7a1, a caulked portion 7c, and a cylindrical heat radiation portion 7d. The external terminal member 8 includes a ring-shaped portion 8a, a connecting portion 8b integrally provided therein,
and a caulking portion 8c.

The heater 6 is held between the ring-shaped parts 7a and 8a of the terminal member 7.8. The pair of terminal members 7.8 are made of metal such as brass or iron.

Of the pair of terminal members 7.8, the portion around which the heater 6 is held and a portion of the connecting portions 7a, 7b are sealed with an electric insulator 9 made of a heat-insulating and heat-resistant synthetic resin.

Note that the clamping portions 7c and 8 of the pair of terminal members 7.8
G, as well as the heat dissipating portion 7d of the terminal member 7 - is not enclosed by the electrical insulator 9 and is exposed to its outside 7' -
, exposed.

As described above, the electrical insulator 9 is one that is clamped and fixed between the carburetor 1 and the intake pipe 2. Therefore, it has a fixing hole 9a, and sealing gaskets LO are attached to the front and back surfaces.

Clamping portions 7c and 8c of the pair of terminal members 7.8
The core wires of the θ side power supply line 1 and the Φ side power supply line 12 are fixed by caulking p-b, respectively. Furthermore, salary? (The caulking fixing portions of the f lines 11 and 12 are protected by a heat-resistant rubber key top 13 as shown by the dashed line.

In the above configuration, by applying a voltage between the power supply lines 11 and 120, a current flows between the pair of terminal members 7.8, and the heater 6 generates heat by itself. This heat is radiated via the ring-shaped portion 7a of the terminal member 7.
d. Therefore, the air-fuel mixture passing inside this heat radiation part 7d is heated.

In addition, in the present invention, electricity,
A ring-shaped elastic body with good thermal conductivity, such as graphite, may be interposed. Further, the heater 6 is not limited to barium ditanate-based ceramic semiconductor porcelain, and may be made of any material as long as it has a self-current control function. Furthermore, the material of the electrical insulator 9 may be, of course, other than heat-resistant resin, such as thermal rubber.

13 and 14 show other embodiments of the invention, in which the connections 7b, 8b of the terminal element 7.8 are not visible due to the cross-section. In addition,
Reference numeral 14 in FIG. 13 is a graphite ring.

As described above, according to the present invention, a heater having a self-current control function is sandwiched between a pair of terminal members,
Since the sandwiched portion is surrounded by a heat-resistant electrical insulator, the fixing structure of the heater is extremely simple. Also,
Since the heater has a self-current control function, there is no need to worry about damage.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an internal combustion engine equipped with an intake air heating device showing an embodiment of the present invention, and FIG.
Fig. 3 is a sectional view taken along the Δ-A line in Fig. 2, Fig. 4 is a plan view showing details.
The figure is a 13-B sectional view in Figure 2, and Figure 5 is a plan view showing the state before the power supply line and gasket are assembled in Figure 2.
Figure 6 is a sectional view taken along line C-C in Figure 5, and Figure 7 is l) in Figure 5.
-D sectional view, FIG. 8 is a plan view showing one side of the terminal member used in an embodiment of this 8-Ming, and FIG. 9 is I of FIG. 8.
EE sectional view, FIG. 10 is a plan view showing the other terminal member used in one embodiment of the present invention, FIG. 11 is a F-1" sectional view of FIG. 10, and FIG. A plan view showing the heater used in one embodiment, and Figs. 13 and 14 are cross-sectional views showing other embodiments of the present invention. 6. F45 heater, 7.8. Terminal member. ,
7b, 8b...connection section, 7d...heat dissipation section, 9...
Electrical insulator, 11.12...Power supply line. Representative Patent Attorney Takashi Okabe 3 Figure 4 Figure 5 Figure 6 Figure 8

Claims (1)

[Claims] A heater having a self-current control function, a pair of terminal members sandwiching the heater, a heat-resistant electric insulator surrounding the heater sandwiching portion of the terminal member, and each of the pair of terminal members A portion of the terminal member is exposed outside the electrical insulator to serve as a connection portion to a power supply line, and another portion of one of the terminal members is exposed from the insulator to serve as a heat dissipation portion. heating device.