JPH0241467B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a steering wheel for an automobile or the like, and particularly to one in which a heating element is provided on a rim portion held by a driver to warm the steering wheel.

[Conventional technology]

As this kind of steering wheel, JP-A-58
- The one shown in Publication No. 183348 is known.

This steering wheel uses a positive temperature coefficient thermistor (ceramic heating element) as a heating element, and this heating element is attached around a rim core metal (metallic core aggregate), and these are attached to a synthetic resin covering (synthetic It is buried in resin skin material).

[Problem that the invention seeks to solve]

In the case of the above-mentioned steering wheel, the heating element is attached around the rim core metal, so the heat from the heating element is absorbed by the rim core metal, making it difficult for the warmth to be transmitted to the surface of the rim, resulting in poor efficiency. However, there is no effect unless the heating element is made larger, and the positive temperature coefficient thermistor itself is more expensive than other heating elements, which is a major cost increase factor.

The present invention has been made in view of the above points, and is designed to efficiently transfer heat from a heating element to the surface of the rim portion,
The purpose is to use a small positive temperature coefficient thermistor as a heating element.

[Means for solving problems]

The present invention relates to a steering wheel in which an annular rim part 1 is connected around a boss part 2 via spoke parts 3, and a heating element made of a positive temperature coefficient thermistor is mounted on the inner surface of heat sink plates 13 and 32 made of, for example, aluminum. 12, and this heating element 1
The heat sink 13, 2 maintains a non-contact state with the heat sinks 13, 32 through the space 17.
32 are attached to the fitting recesses 11, 31 formed in, for example, two gripped parts of the rim part 1, and at least the outer surfaces of the heat dissipating plates 13, 32 are covered with a cover body made of, for example, natural or synthetic leather 8. It is characterized by being covered with

[Effect]

The steering wheel of the present invention includes a heating element 12
The heat is directly transferred to the heat sinks 13 and 32 near the surface of the rim portion 1, thereby efficiently utilizing the heat.

〔Example〕

Embodiments of the steering wheel of the present invention will be described with reference to the drawings.

1 to 4 show a first embodiment.

In FIGS. 1 to 4, reference numeral 1 denotes an annular rim portion, and this rim portion 1 is connected around a boss portion 2 via a pair of spoke portions 3. As shown in FIG.

The rim portion 1 has an annular rim core 6 embedded in a synthetic resin cover 7, and the cover 7 is covered with natural or synthetic leather 8 as a cover. The metal 6 is connected to the metal boss 1 of the boss portion 2 via the spoke core metal 9 of each spoke portion 3.
0 by welding or the like.

Fitting recesses 11 recessed in two stages are formed on the surface of the covering 7 at two portions of the rim portion 1 that are gripped by the driver, and each of the fitting recesses 11 has a positive characteristic. A heating element 12 made of a thermistor and a heat sink 13 made of aluminum
is installed.

That is, one of the thin film-like current-carrying electrodes 12a formed by plating or the like on both sides of each heating element 12 is attached to one of the fitting recesses 11 recessed in two stages through the conductive adhesive 6. Each heat sink 13 is bonded to the inner surface of each of the heat sinks 13 formed in the same shape as the first recess 11a of the row, and each heat sink 13 is attached to the first recess 11 of each fitting recess 11.
Fitted into the recess 11a, each heat sink 13 is flush with the surface of the covering 7 of the rim portion 1 and covered with the leather 8, and each heating element 12 has a space 17 around it. The second recess 1 in the second stage of each fitting recess 11 is in non-contact with anything other than the heat sink 13 via the space 17.
1b.

The other electrode 12a of each heating element 12 is
A lead wire 20 is connected to the conductive adhesive 21,
Each lead wire 20 is connected to a slip ring 23 of the boss portion 2 via a switch 22, and this slip ring 23 is electrically connected to the positive terminal of the battery, so that the other electrode 12a of each heating element 12 is connected to the positive terminal of the battery. The lead wires 24 are connected to the inner surface of each of the heat sinks 13 with a conductive adhesive 25.
is connected to the boss 10 of the boss part 2, and this boss 10
is electrically connected to the negative terminal of the battery, so one electrode 12a of each heating element 12 is electrically connected to the negative terminal of the battery.

Therefore, when the switch 22 is turned on, each heating element 12 is energized, each heating element 12 generates heat and each heat sink 13 is warmed, and when the temperature rises, the resistance of the positive temperature coefficient thermistor used for each heating element 12 increases. The amount of heat generated decreases, reaching an equilibrium state at a predetermined temperature and maintaining that temperature.

At this time, since each heating element 12 is not in contact with anything other than the heat sink 13, the heat is not easily absorbed by the rim core bar 6 and the covering body 7, and the heat can be used efficiently. It is possible to use a small positive temperature coefficient thermistor that rises quickly, consumes little power, and is inexpensive.

Further, since the space 17 is present, the material of the covering body 7 can be saved and the weight can also be reduced.

Further, FIG. 5 shows a second embodiment. In this second embodiment, only the parts that are different from the first embodiment described above will be explained.

In the embodiment shown in FIG. 5, the covering 7 of the rim portion 1 is
A fitting recess 31 recessed in one step is formed at two locations, and both side walls 31a of each fitting recess 31 are formed in an eight-shaped shape that widens toward the bottom 31b of each fitting recess 31. Correspondingly, a substantially U-shaped heat dissipating plate 32 made of aluminum is used, which has expanded bent pieces 32a on both sides that are engaged with the eight-shaped side walls 31a of the fitting recess 31.

Therefore, each heat sink 3 to which a heating element 12 is attached
2 is attached to each fitting recess 31, each heat dissipation plate 32 does not move, making it easier to wrap and sew the leather 8.

FIG. 6 shows a modification of the second embodiment shown in FIG. 5, in which one electrode 12a of each heating element 12 is connected to the rim core bar 6 via a metal spring 35,
This one electrode 12a is electrically connected to the negative terminal of the battery via the rim core metal 6, the spoke core metal 9, and the boss 10, eliminating the need for one lead wire each, and each spring 35 is connected to the cover 7. One electrode 1 of the heating element 12 is disposed in a through hole 36 bored from the bottom 31b of the fitting recess 31 toward the rim core 6.
It is installed between the rim core bar 2a and the rim core bar 6 in a compressed manner. In addition, in the case of this modification, the other electrode 12a of each heating element 12 is connected to each heat sink 32;
The positive terminal of the battery is electrically connected through the lead wire connected to the switch 22 and the slip ring 23.

FIG. 7 is also a modification of the second embodiment shown in FIG. 5, in which each heating element 12 is fixed with locking claws 32b cut and raised from both side walls 32a of each heat sink 32. An insulating plate 39 is interposed between each locking claw 32b and the other electrode 12a of the heating element 12.

In each of the embodiments and modifications described above, the outer surfaces of the heat sinks 13 and 32 are directly covered with the leather 8, but since the driver always grips this part,
Considering the case where the leather 8 is moved on the outer surface of the heat sinks 13, 32, a film made of silicone rubber, vinyl chloride resin, etc. with good wear resistance is provided between the heat sinks 13, 32 and the leather 8. Good too.

When the covering body 7 is made of a soft material such as soft vinyl chloride resin or foamed urethane resin, the heat sinks 13 and 32 are made of leather to make the grip feel of the heat sinks 13 and 32 the same as the other parts. An elastic film made of a soft material such as soft vinyl chloride resin or foamed urethane resin may be provided between the covering member 7 and the cover member 7 .

Further, in each of the embodiments and modifications described above, the leather 8 is used as the cover body, but a synthetic resin layer may be molded in a mold as the cover body.

In each of the embodiments and modifications described above, the positive temperature coefficient thermistor used in the heating element 12 is made of barium titanate-based ceramic, for example, and whose resistance value increases rapidly at a desired temperature. It is used to increase the temperature and quickly reach equilibrium.

In addition, although aluminum is used for the heat sinks 13 and 32 in consideration of workability, weight, thermal conductivity, etc., other materials such as iron, copper, brass, etc. may also be used.

〔Effect of the invention〕

As described above, according to the present invention, since the heating element is in a non-contact state with anything other than the heat sink through the space, most of the heat from the heating element is directly transferred to the heat sink near the surface of the rim part. Since the heat of the heating element can be efficiently used, an inexpensive and small positive temperature coefficient thermistor of the heating element can be used, and the weight can be reduced due to space.

[Brief explanation of the drawing]

1 to 4 show a first embodiment of the steering wheel of the present invention, in which FIG. 1 is a plan view thereof, FIG. 2 is an exploded perspective view of its main parts, and FIGS. 3 and 4 are FIG. 5 is a cross-sectional view of the main part showing a second embodiment of the steering wheel of the present invention, and FIG. 6 and FIG. 7 each show a modification thereof. It is a sectional view of the main part. DESCRIPTION OF SYMBOLS 1... Rim part, 2... Boss part, 3... Spoke part, 8... Leather as a cover body, 11... Fitting recessed part, 12... Heat generating element, 13... Heat sink, 17...
...Space, 31... Fitting recess, 31a... Side wall of fitting recess 31, 31b... Bottom of fitting recess 31, 3
2... Heat sink, 32a... Bent piece of heat sink 32.

Claims (1)

[Scope of Claims] 1. In a steering wheel in which an annular rim part is connected around a boss part through spoke parts, a heating element made of a positive temperature coefficient thermistor is attached to the inner surface of a heat sink, and the heating element is a part other than the heat sink. means that a heat sink is installed in a fitting recess formed in the gripped portion of the rim part so as to maintain a non-contact state through a space, and at least the outer surface of this heat sink is covered with a cover body. A steering wheel featuring 2. The steering wheel according to claim 1, wherein the heat sink is made of aluminum. 3 The opposite side walls of the fitting recess are formed in a figure-eight shape that widens toward the bottom of the fitting recess, and the heat sink is engaged with the figure-eight-shaped both side walls of the fitting recess on both sides. The steering wheel according to claim 1 or 2, characterized in that the steering wheel is formed in a substantially U-shape having an expanded bent piece that is stopped. 4. The steering wheel according to any one of claims 1 to 3, wherein the cover body is made of natural or synthetic leather.