JPH0542875A - Steering wheel - Google Patents

Abstract

PURPOSE:To detect and decide simply and surely the perspiring condition and tense condition of a driver by embedding at a ring portion where a covering material at a steering wheel main body is formed, a humidity sensor to detect water given out from a palm gripping the ring portion. CONSTITUTION:A steering wheel main body 1 has a ring portion 2, spoke portions 3 and a pad portion 4 covering a boss portion, with a core metal 5 as a base. Also, a synthetic resin layer and a covering material 7 are formed in order at the outer periphery of the core metal 5. In this instance, an insertion hole 8 for a humidity sensor 10 is drillingly provided on the anti-pad side of the ring portion 2 at the synthetic resin layer. Also, an appropriate number of small holes are drillingly provided at the covering material 7 that is located on the upper surface of the sensor 10. In addition, the sensor 10 is housed at the inside of a housing 11, and a humidity permeable member 12 is provided at the opening portion of the housing 11. And the perspiring amount of a palm gripping a steering wheel is detected as the change of humidity and by this, the tense condition of an operator is decided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a humidity sensor arranged in a ring portion of a steering wheel body.
In particular, the present invention relates to a steering wheel that detects moisture such as sweat emanating from a palm holding a ring portion of a steering wheel body.

[0002]

2. Description of the Related Art As a conventional steering wheel of this type, there is a technology disclosed in Japanese Utility Model Laid-Open No. 53-84841.

That is, two electrodes mounted on the steering wheel of a vehicle which are constantly operated by the driver's palm while the vehicle is traveling and which come into contact with the driver's palm, and a current flowing between the electrodes via the driver's palm A circuit for detecting a differential value, a circuit for detecting that the differential value detected by the detection circuit is below a predetermined level for a certain period of time and outputting a signal, and an alarm device which operates by an output signal of the circuit are provided. And is used as a drowsiness driving alarm device.

[0004]

As described above, the conventional drowsiness driving warning device determines whether or not the vehicle is dozing by changing the resistance value between the two electrodes mounted on the steering wheel of the vehicle. However, the judgment of the resistance value between the two electrodes changes depending on the grip pressure, the conductivity of the skin surface, the resistance value peculiar to each person, etc., and it is not possible to always make the same conditions, so the driving conditions of the driver Was not always satisfactory to detect.

That is, in order to detect the driving condition of the driver only by judging the resistance value between the two electrodes, there is a possibility that the conclusion may change due to other external requirements.

However, the palm holding the steering wheel of the driver outputs specific state information of the human body which the driver is not aware of, and it is desired to transmit it to the driver appropriately. ..

Therefore, an object of the present invention is to provide a steering wheel capable of detecting the degree of tension of the driver from the palm holding the steering wheel.

[0008]

In a steering wheel according to the present invention, a ring portion is covered with a covering material, a plurality of humidity sensors are embedded in the ring portion, and moisture released from the palm holding the ring portion is absorbed. Is to detect.

[0009]

In the present invention, a plurality of humidity sensors are embedded in the ring portion of the steering wheel body enclosing the covering material, and the amount of sweat such as sweat radiated from the palm holding the ring portion or the rate of change of the amount of sweat is measured. It is detected and used as the driver's tension.

[0010]

EXAMPLES Examples of the present invention will be described below.

FIG. 1 (a) is a plan view of an essential part of the steering wheel according to an embodiment of the present invention, in which a ring portion has a partially cut surface, and FIG. 1 (b) is attached to the steering wheel of the embodiment. It is the whole humidity sensor perspective view. FIG. 2 is a sectional view of a ring portion of a steering wheel according to an embodiment of the present invention.

In the drawing, a steering wheel body 1
As is well known, has a pad portion 4 that covers the ring portion 2, the spoke portion 3, and the boss portion based on the core metal 5.
The steering wheel body 1 used in this embodiment
Are not necessarily limited to those having the cored bar 5, and a steering wheel without the cored bar 5 may be used. Synthetic resin layer 6 with injection molding or the like on the outer periphery of the core metal 5
Is molded of vinyl chloride or a material known as a steering wheel such as integral skin urethane foam. Further, on the outer periphery of the synthetic resin layer 6, a covering material 7 made of a skin layer made of synthetic leather is formed. The coating material 7 is subjected to color and surface treatment according to the taste of the user. An adhesive is used for encapsulating the covering material 7, and they are firmly integrated with the synthetic resin layer 6.

On a side opposite to the pad of the ring portion 2 of the synthetic resin layer 6, an insertion hole 8 having a diameter of a casing of a humidity sensor 10 which will be described later is provided at a predetermined required position. Although it is desirable that the depth of the insertion hole 8 reaches the core metal 5, the depth of the insertion hole 8 matches the height of the humidity sensor 10, and the upper surface of the humidity sensor 10 is the synthetic resin layer 6. It should match the surface. The covering material 7 located on the upper surface of the humidity sensor 10 is provided with one or a plurality of small holes 7a.

A well-known humidity sensor can be used as the humidity sensor 10, and for example, a thermistor absolute humidity sensor, a polymer film humidity sensor, a ceramic humidity sensor, or the like can be used. The humidity sensor 10 of this embodiment is formed by vapor-depositing a moisture sensitive material on an alumina substrate. The humidity sensor 10 is housed in a housing 11 that constitutes a casing. Housing 11 of the humidity sensor 10
A moisture-permeable member 12 such as a transparent mesh or GORE-TEX (trademark) is disposed in the opening of the.

In order to manufacture the steering wheel of this embodiment, first, the target steering wheel body 1 is to be manufactured.
The synthetic resin layer 6 is injection-molded on the core metal 5 of the same, and at the same time, the insertion hole 8 matching the size of the housing 11 is formed at a predetermined position.
To provide. At this time, the place where the insertion hole 8 is drilled is determined by the position of the driver's palm in a normal state during straight running, but the specific place or the specific place It may be drilled in a predetermined range including or. Then, the humidity sensor 10 is inserted therein, the lead wire 13 is inserted in the lead wire insertion groove 9 formed along the outer periphery of the ring portion 2, and the end portion thereof is built in the pad portion 4. Input to the humidity detection circuit of 3. The outer circumference of the ring portion 2 and the humidity sensor 10 is covered with a covering material 7 made of synthetic leather which is color-treated and surface-treated according to the user's preference, and the covering material 7 is provided with a single or plural holes. The small hole 7a is made to correspond to the humidity permeable member 12 side of the humidity sensor 10.

The humidity sensor 10 is constructed like a humidity detecting circuit arranged in the pad portion 4 of this embodiment shown in FIG.

First, when the output of the rectangular wave generating circuit 21 is constantly applied to the humidity sensor 10 and the humidity sensor 10 detects humidity, it is determined that the resistance value of the humidity sensor 10 with respect to the relative humidity decreases. The wave height of a rectangular wave corresponding to the decrease of the resistance value with respect to is set as a DC voltage that continuously changes in the DC voltage conversion circuit 22, the output of the DC voltage conversion circuit 22 is amplified by the amplification circuit 23, and the output of the amplification circuit 23 is further changed by The temperature is compensated by the humidity correction circuit 24, its output is differentiated by the differentiating circuit 25, and only the increasing component is extracted as the magnitude of the rate of change, and this is used as the predetermined rate of change threshold value of the threshold value output circuit 27 by the comparison circuit 26. In comparison, when the output of the differentiating circuit 25 is larger than the output of the predetermined threshold value output circuit 27, the OR gate 2
8. After the ignition switch 29 is turned on, a buzzer and a lamp are opened via the AND gate 31 which opens the gate by the output of the time circuit 30 which sets the output signal to “H” after the elapse of the time to rise to the normal steady state. The visual and / or audible notification means 32 such as

On the other hand, the output temperature-compensated by the temperature-humidity correction circuit 24 is compared with a predetermined change threshold value of the threshold value output circuit 34 by the comparison circuit 33, and the output of the temperature-humidity correction circuit 24 is changed by a predetermined threshold value output circuit. When the output is larger than 34, the gate is opened by the output of the time limit circuit 30 which sets the output signal to "H" after the time when the OR gate 28 and the ignition switch 29 are turned on and after the time to rise to the normal steady state has elapsed. A visual and / or audible notification means 32 such as a buzzer or a lamp is driven via the gate 31.

The steering wheel of this embodiment constructed as described above operates as follows.

In general, the time limit of the time limit circuit 30 is set after the driver grips the steering wheel and the coating material 7 which has been in a dry state until then is covered with a single coating material 7 such as moisture radiated from the palm. Alternatively, the time period for entering the housing 11 of the humidity sensor 10 through the plurality of small holes 7a and setting the humidity state during the normal operation unique to the driver is set to about 1 to 5 minutes.

When the driver gets into the vehicle and turns on the ignition switch 29 to start driving the vehicle, the time limit circuit 30 has a time limit for rising to a normal steady state. Output becomes "L",
The AND gate 31 remains closed. Pad part 4
In the humidity detection circuit arranged in, the rectangular wave generation circuit 21 applies a rectangular wave having a predetermined repetition frequency to the humidity sensor 10.

Therefore, in the initial stage when the driver holds the steering wheel, the coating material 7 which has been in a dry state until then is suddenly exposed to moisture such as perspiration from the palm in the normal state. Alternatively, the humidity enters the housing 11 of the humidity sensor 10 through the plurality of small holes 7a. Therefore, the humidity sensor 10 catches it and changes the resistance value, is arranged on the pad portion 4 through the lead wire 13 and is output to the humidity detecting circuit. As a result, the humidity sensor 10 is set to the time limit circuit 30. Until the time limit elapses, the AND gate 31 is closed by the output of the time limit circuit 30, and the notification means 32 such as a buzzer is not driven.

After the time limit set in the time limit circuit 30 has passed, the AND gate 31 is opened.

Moisture such as sweat radiated from the palm holding the steering wheel 1 becomes the humidity in the housing 11 of the humidity sensor 10 through the single or plural small holes 7a of the covering material 7. The humidity sensor 10 captures it and changes the resistance value, and in the humidity detection circuit arranged in the pad section 4, as a change in the peak value of the rectangular wave of the predetermined repetition frequency applied by the rectangular wave generation circuit 21, It outputs to the humidity detection circuit arranged in the pad section 4 via the lead wire 13. In the humidity detecting circuit arranged in the pad portion 4, the wave height of the rectangular wave corresponding to the decrease in the resistance value of the humidity sensor 10 with respect to the relative humidity is continuously smoothed by the DC voltage converting circuit 22 without ripple. DC voltage conversion circuit 2
The output of No. 2 is amplified by the amplifier circuit 23, and the temperature-humidity correction circuit 24 temperature-compensates the characteristic of the humidity sensor 10 to make it a linear characteristic. Further, the output is differentiated by the differentiating circuit 25 to detect the increase rate, and by this, it is judged whether or not the sweat radiated from the palm is rapidly increasing. When the increase is larger than the output of the threshold value output circuit 27, the notifying means 32 such as a buzzer is driven via the OR gate 28 and the AND gate 31 to notify the driver that the user is currently in an extremely tense state.

Further, the output temperature-compensated by the temperature-humidity correction circuit 24 is compared with a predetermined change threshold value of the threshold value output circuit 34 by the comparison circuit 33, so that the amount of sweat radiated from the palm increases and the temperature- When the output of the humidity correction circuit 24 is larger than the output of the predetermined threshold value output circuit 34, the OR gate 28,
A notification device 32 such as a buzzer is driven via the AND gate 31.

As described above, in the steering wheel according to the embodiment of the present invention, the steering wheel body 1 in which the ring portion 2 is covered with the coating material 7 and the steering wheel body 1 has a plurality of ring portions. The humidity sensor 10 is embedded and detects the moisture released from the palm holding the ring portion 2.

Therefore, from the palm gripping the ring portion 2 of the steering wheel 1, the humidity inside the housing 11 of the plurality of humidity sensors 10 embedded in the ring portion 2 through the single or plural small holes 7a of the covering material 7. To raise. In particular,
Since it is known to humans that their palms sweat with extreme tension, the amount of sweat generated can be detected as the high humidity, and the amount of sweat can determine the degree of driver's tension. In particular, when steering at high speed on a highway or the like, the humidity sensor 10 at a specific detection position detects the amount of sweating without a sudden change of the steering wheel, which corresponds to the driver's tension. It becomes the output of the notification means 32. Further, according to the experiments by the present inventors, the individual difference in humidity in the humidity sensor 10 in the palm of the driver who is the subject is as shown in FIG. 4, and there is a predetermined range of humidity difference. is doing. Then, in this type of normal state, the humidity sensor 10
However, the relative humidity threshold value is set to about 95% because it is considered to be a driver's health problem or abnormal tension.

When a person is in an extremely tense state, the amount of sweat from the palm increases rapidly. By passing this through the differentiating circuit 25, it is possible to judge that the driver's tension is increasing and detect it.

At this time, the covering material 7 forming the atmosphere of the humidity sensor 10 has one or a plurality of small holes 7a formed therein, but the generated humidity is retained by the covering material 7 and is kept in a normal state with time. Restored to. That is, the maintenance of the humidity in the covering material 7 is the time required for the driver to relieve the tension, and is not affected in the case of using it as the tension detection.

By the way, the steering wheel of the above embodiment is the steering wheel body 1 in which the ring portion 2 is covered with the covering material 7. However, in the case of implementing the present invention, the ring portion 2 is covered with the covering material 7. It is not limited to what is enclosed, but only the synthetic resin layer 6, the synthetic resin layer 6
For example, the one using integral skin urethane foam can be used. However, in the case where the ring portion 2 is covered with the covering material 7, since the exposure of the humidity sensor 10 can be hidden by the covering material 7, the appearance can be improved. Of course, by treating the exposed surface of the humidity sensor 10 with a material equivalent to the covering material 7, the humidity sensor 10 can be exposed from the through hole formed in the covering material 7.

Further, the steering wheel of the above embodiment has a plurality of humidity sensors 10 embedded in the ring portion 2 of the steering wheel main body 1 for detecting the moisture released from the palm holding the ring portion 2. However, the number of the humidity sensors 10 need only be at least at the position of the ring portion 2 of the steering wheel that is gripped by both palms, and it is sufficient if two or more are provided.

[0032]

As described above, according to the steering wheel of the present invention, a steering wheel main body having a ring portion covered with a covering material and a plurality of palms embedded in the ring portion of the steering wheel main body to grip the ring portion. And a humidity sensor that detects the moisture emitted from the.

Therefore, from the palm which holds the steering wheel, a plurality of humidity sensors embedded in the ring portion detect the amount of perspiration and / or its variation as a change in humidity, and the amount of perspiration and / or its variation. Since the driver's tension state can be judged by the output of the notification means corresponding to the driver's degree of tension, escape from the tension state,
The tension can be relieved. Therefore, it is possible to accurately transmit to the driver the information on the tension state of the human body that the driver is not aware of.

[Brief description of drawings]

FIG. 1 (a) is a plan view of an essential part of a steering wheel according to an embodiment of the present invention, which has a partially cut surface in a ring portion, and FIG. 1 (b) is an overall perspective view of a humidity sensor to be inserted. is there.

FIG. 2 is a sectional view of a ring portion of a steering wheel according to an embodiment of the present invention.

FIG. 3 is a circuit diagram of a humidity detecting circuit arranged in a pad portion of a steering wheel according to an embodiment of the present invention.

FIG. 4 is a characteristic diagram of a humidity sensor in a palm held by a subject by a steering wheel according to an embodiment of the present invention.

[Explanation of symbols]

 1 Steering wheel body 2 Ring part 7 Coating material 10 Humidity sensor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hirano Atsushi Hirano 1 Ochiai, Nagachi, Kasuga-cho, Nishikasugai-gun, Aichi Toyoda Gosei Co., Ltd. Toyoda Gosei Co., Ltd.

Claims (1)

[Claims] 1. A steering wheel body having a ring portion covered with a coating material, and a plurality of humidity sensors embedded in the ring portion of the steering wheel body for detecting moisture radiated from a palm holding the ring portion. A steering wheel characterized by being provided.