JPH0119480Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a steering wheel device used in a steering mechanism of an automobile, particularly to a signal transmission means.

In conventional steering wheel devices, the horn switch generally rotates together with the rotation of the rim. However, recently, a device has been developed in which a non-rotating body, a so-called non-rotating pad, is provided on the inner side of the rim portion so as to remain relatively stationary regardless of rotation of the rim portion.

A steering wheel device having such a non-rotating body has the advantage that not only a horn switch but also various switches and indicators can be attached because the non-rotating body does not move. The structure of the slip ring and brush part for electrical connection to the vehicle body is complicated, and installation is extremely difficult due to space constraints.

In order to solve this problem, there is also a system that multiplexes and unifies a plurality of signals from each switch and transmits them using a single signal line. It is also known to perform electrical to optical conversion of the multiplexed communication signal and transmit the signal using an optical fiber cable.

In order to transmit signals from switches to the vehicle body using optical communication as described above, the following signal transmission means have been considered. That is, as illustrated in FIG. 1, a light guide ring a that rotates together with the steering wheel is attached to the steering wheel, and a light emitter b is attached to the light guide ring a. This light emitter b is connected to a signal transmitter that multiplexes and optically converts a plurality of signals output from each switch. The light emitter b is designed to rotate together with the light guiding ring a.

On the other hand, a light receiver c for receiving the light transmitted from the light guiding ring a is arranged on a fixed member on the vehicle body side, such as a steering column cover. This light receiver c is connected to a receiver via an optical fiber cable, and the received optical signal is reconverted into an electric signal to operate an actuator.

However, in the method using the light guide ring a, since the light emitter b rotates relative to the light receiver c (fixed), the distance of the light emitter b to the light receiver c changes. In addition, the optical signals emitted from the same light emitter b are transmitted within the light guide ring a with a time difference in the clockwise and counterclockwise directions depending on the position of the light emitter b, which may cause erroneous signals. may occur. In addition, since light is transmitted by repeatedly reflecting the interior of the light guide ring over a relatively long distance, there are problems with reliability, such as attenuation of the amount of light and phase shift due to repeated reflections.

Therefore, the present inventor placed a light emitter and a light receiver facing each other on the mutually opposing surfaces of a member on the vehicle body side such as a steering column and the non-rotating body, and directly exchanged signals between the light emitter and the light receiver. I thought about that. However, since the rim of a steering wheel may be rotated by more than 360 degrees when steering, no matter where the emitter and receiver are placed, the spokes that move together with the rim can rotate the steering wheel more than 360 degrees. It was found that there were moments when the light from the emitter was blocked by the spokes and did not reach the receiver.

The present invention was developed based on the above circumstances, and its purpose is to ensure that signals are transmitted even if the spokes that rotate integrally with the rim block the space between the vehicle body side member and the non-rotating body. It is an object of the present invention to provide a steering wheel device that can transmit light, eliminates the need for a light guide ring as described above, improves light transmission efficiency, and has high reliability.

In other words, the steering wheel device of the present invention is
A steering wheel consisting of a rim part, a spoke part, and a boss part, which is rotatably provided with respect to a member on the vehicle body side; a non-rotating body located on the opposite side of the spoke portion; a stationary mechanism that holds the non-rotating body relatively stationary with respect to a member on the vehicle body side regardless of rotation of the rim portion; A plurality of switches arranged on a rotating body, a signal transmitter that multiplexes and optically converts a plurality of signals output from these switches, and a steering wheel are connected to each other on a surface of the non-rotating body facing the vehicle body side member. two or more light emitters that are spaced apart in the circumferential direction and placed in positions where the light is not simultaneously blocked by the spoke portions, and that branch the signal into two or more systems and emit light simultaneously; and the member on the vehicle body side. includes a plurality of light receivers arranged at positions separated from and facing each of the light emitters, and a receiver connected to each of the light emitters for merging signals from each light emitter and reconverting them into electrical signals. are doing.

In the present invention with the above configuration, even when the steering wheel is rotated, the non-rotating body remains apparently stationary.
Therefore, the light emitter and the light receiver can always face each other at a fixed position. Moreover, two or more of these light emitters and light receivers are each arranged along the circumferential direction of the steering wheel, so as the steering wheel rotates, some of the light emitters and light receivers are blocked by the spokes. Even if the remaining light emitters and light receivers are blocked simultaneously, the remaining light emitters and light receivers can be placed in positions where simultaneous light shielding does not occur, and there is no fear that the optical signal will be interrupted.

The above structure eliminates the need for a conventional light guide ring, and because the emitter and receiver face each other directly, the light transmission efficiency is high, and high reliability is achieved without the risk of erroneous signals due to time differences unlike with the light guide ring. It is something.

An embodiment of the present invention will be described below with reference to FIGS. 2 to 5. In FIG. 2, numeral 1 indicates a steering shaft. The steering shaft 1 is rotatably supported via a bearing 2 to a steering column cover 3, which is an example of a member on the vehicle body side.

A steering wheel 4 is attached to the steering shaft 1. The steering wheel 4 includes a circular rim portion 5, a boss portion 6 located at the center of the rim portion 5, and spoke portions 7 connecting the boss portion 6 and the rim portion 5. The boss portion 6 is fixed to the serration portion 8 of the steering shaft. Therefore, when the rim portion 5 is rotated, the boss portion 6 and the steering shaft 1 rotate together.

Furthermore, a non-rotating body 10 is attached to the end of the steering shaft 1. This non-rotating body 10
is bearing 10 for steering shaft 1
Although it is rotatable via the steering column cover 3, it is supported in a relatively stationary state with respect to the steering column cover 3 by the action of a stationary mechanism 11 described below.

Although various types of static mechanism 11 are conceivable, in this embodiment, a planetary gear type is used as an example. That is, while providing the fixed gear 12 on the steering column cover 3,
A stationary gear 13 having the same number of teeth as the stationary gear 12 is provided on the non-rotating body 10. The fixed gear 12 and the stationary gear 13 are positioned on the same axis. Planetary gears 14 and 15 are meshed with both gears 12 and 13. The shafts 16 of these planetary gears 14 and 15 are supported by boss portions 6 or spoke portions 7.

Therefore, when the rim portion 5 is rotated, the planetary gear 14 rotates while revolving around the fixed gear 12 and rotates the other planetary gear 15.
The stationary gear 13 meshing with the non-rotating body 10
The steering column cover 3 is also held at the same position relative to the steering column cover 3, and appears not to rotate.

A horn switch, lights, turn signals, wipers, cruise control, and other switches 20 are arranged on the non-rotating body 10. As illustrated in FIG. 5, the non-rotating body 10 is provided with a signal transmitter 21 to which the switches 20 are connected. This signal transmitter 21 unifies the electrical signals of the switches 20 as multiplexed signals (parallel signal→serial signal), converts them into optical signals, and causes the light emitters 22, 22 to emit light.

These light emitters 22, 22 are two or more, and the third
By arranging them apart from each other in the circumferential direction of the steering wheel as illustrated in the figure, at least one of these light emitters 22, 22 is not blocked from light no matter what rotational position the spoke portion 7 is in. There is.

A member on the vehicle body side, for example, the column cover 3, is provided with a position facing away from the light emitters 22, 22.
For example, light receivers 23, 23 such as condensing lenses are arranged. Optical fiber cables 24, 24 are connected to these light receivers 23, 23, respectively. The optical fiber cables 24, 24 are then merged into one and connected to the receiver 25. The receiver 25 converts the optical signal into an electrical signal using a photodiode or phototransistor, and also converts a serial signal to a parallel signal, and outputs a drive signal to the actuator 26 corresponding to the switch 20. do. Therefore, various devices operate according to the operated switch. Note that the distance between the light emitter 22 and the light receiver 23 is, for example, about 10 to 30 mm.

In this embodiment with the above configuration, when the rim portion 5 is rotated, the steering shaft 1 is rotated, but since the non-rotating body 10 is stationary, the positions of the light emitters 22, 22 and the light receivers 23, 23 are always relative to each other. constant. Therefore, when the switches 20 are operated, the signal is optically converted and input to the light receivers 23, 23.
Actuator 26 can be driven.

Furthermore, when the rim portion 5 is rotated, the light from one of the light emitters 22 may be blocked depending on the position of the spoke portions 7, but in this case, the light from the other light emitter 22 and the light receiver 23 may be blocked. Since the spoke portions 7 are not located in between, there is no fear that the optical signal will be interrupted, and the signal can be transmitted at all times regardless of the rotation of the rim portion 5.

The optical communication system described above is more resistant to noise than electrical communication systems, and does not require sliding contacts such as slip rings and brushes, allowing contactless signal transmission. In addition, since the emitter and receiver form a one-to-one couple, there is no generation of erroneous signals due to time differences or losses due to repeated reflections that occur when using a light guiding ring, resulting in high efficiency and high reliability. That's what you get.

Note that the mechanism for stopping the non-rotating body is not limited to the above-mentioned planetary gear system. For example, in a so-called two-axis steering wheel device, the steering wheel is rotatably supported by a fixed shaft separate from the steering shaft, and a non-rotating body is fixed to the end of this fixed shaft, and the power of the gear etc. It may be a mechanism that uses a transmission mechanism to transmit the rotational force of the steering wheel to the steering shaft.

As described above, according to the present invention, even if the space between the vehicle body side member and the non-rotating body is interrupted by the spokes as the rim rotates during steering, the spokes are provided on the non-rotating body. Signals from switches can be reliably transmitted to the receiver on the vehicle body. This eliminates the need for a light guide ring, which has a significant effect in improving light transmission efficiency and reliability.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram illustrating a light guide ring, FIGS. 2 to 5 show an embodiment of the present invention, FIG. 2 is a sectional view of a part of the steering wheel device, and FIG.
The figure is a front view, FIG. 4 is a schematic perspective view of the non-rotating body and the steering column cover, and FIG. 5 is a circuit diagram of the signal transmission system. DESCRIPTION OF SYMBOLS 1... Steering shaft, 3... Steering column cover (body side member), 4... Steering wheel, 5... Rim part, 7... Spoke part, 11... Stationary mechanism, 10... Non-rotating body, 20
...Switches, 21...Signal oscillator, 22...
...Emitter, 23...Receiver, 25...Receiver.

Claims (1)

[Scope of Claim for Utility Model Registration] A steering wheel consisting of a rim part, a spoke part and a boss part which is rotatably provided with respect to a member on the vehicle body side, and which is provided on the inner part of the rim part of the steering wheel. a non-rotating body located on the opposite side of the spoke part with respect to the body-side member; a stationary mechanism for holding; a plurality of switches disposed on the non-rotating body; a signal transmitter that multiplexes and optically converts a plurality of signals output from these switches; and the vehicle body side member of the non-rotating body. Two or more light emitting lights that are spaced apart from each other in the circumferential direction of the steering wheel on opposing surfaces and are arranged in positions where the light is not simultaneously blocked by the spoke parts, and that branch the signal into two or more systems and emit light simultaneously. a plurality of light receivers arranged on the vehicle body side member at positions facing away from each of the light emitters; A steering wheel device comprising: a receiver for reconversion;