JPS59188799A - Multiplex signal transmitter for vehicle - 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 This invention multiplexes input signals from a plurality of switches provided on a steering wheel in a vehicle, converts the signals into optical signals, and then transmits the signals to a fixed part in the vehicle. The present invention also relates to a multiplex signal transmission device for a vehicle, which receives a multiplexed signal by a light receiving element provided on the fixed part and further demultiplexes the multiplexed signal from the light receiving element.

<Prior Art> As shown in FIGS. 1 and 2, a conventional multiple signal transmission device of this type has a steering handle 11 equipped with a plurality of switches 12 for various indicator lights, air conditioning, seven radio sets, etc. The signals inputted to the plurality of switches 12 are multiplexed by the encoder 13, and the multiplexed signal causes the light emitting element 15 to emit light through the single drive circuit 14. The light emitting element 15 is provided within a light guide ring 16 made of acrylic resin, for example, and light from the light emitting element 15 propagates within the light guide ring 16.

As shown in FIG. 2, a light receiving element 17 is provided on a fixed part, that is, on the vehicle body side, close to and facing the outer peripheral surface of the light guide ring 16, and the light received by the light receiving element 17 and leaving the light guide ring 16 is transmitted to a transmission path 18. The amplified output is waveform-shaped by a waveform shaping circuit 21, and further supplied to a decoder 2.
λ light guide ring 1 which is demultiplexed at 0 and in which one or more of the loads 23 corresponding to each of the switches 12 is controlled
6 are rotated simultaneously by the operation of the steering wheel 11, and the diameter thereof is, for example, about 60 mm. Therefore, if the light emitting element 15 or the light receiving element 17 is close to each other, a sufficiently strong optical signal can be received from the light guide ring 16. If this is possible, the level of the optical signal received by the light receiving element 17 will be significantly lowered. In other words, in this conventional device, it is difficult to output a uniform optical signal over the entire circumferential surface of the light guide ring 16.

In order to make the output of the optical signal almost uniform on each part of the circumferential surface of the light guide ring 16, it is possible to make cuts or the like inside the light guide ring 16, but if the light guide ring 16 has a complicated shape, Since the light level in each part of the light guide/group 16 is relatively weak, it is necessary to increase the sensitivity of the amplifier 19 in order to detect optical signals. Therefore, increasing the sensitivity of the amplifier 19 is not preferable because it tends to become unstable.There is also a risk that external noise will be induced in the cable 18 between the light receiving element 17 and the amplifier 19.

<Summary of the Invention> An object of the present invention is to provide a multiplex signal transmission device for a vehicle that has a relatively simple structure and can stably obtain a substantially uniform optical signal regardless of the rotational angle position of the steering wheel. There is a particular thing.

According to this invention, signals inputted by a plurality of switches provided on a steering wheel are multiplexed, and a plurality of light emitting elements are simultaneously driven by the multiplexed signals. The plurality of light emitting elements are arranged at approximately equal angular intervals on a circumference centered on the steering shaft.
The chip of each light emitting element is directly attached to a wiring board, and the wiring board is attached to a rotating part that rotates together with a steering shaft. On the other hand, a light ring forming nozzle is provided to direct the light from each light emitting element to form one ring-shaped light irradiation surface that is uniform as a whole. This optical ring forming housing is provided on the wiring board side. On the other hand, a light receiving element is provided on a fixed part on the vehicle body side in close opposition to the ring-shaped light irradiation surface. The light is received by this light-receiving element and converted into an electric signal, which is further demultiplexed by a demultiplexing circuit, and its output is used to drive each load.

<Embodiment> Electrical system FIG. 3 shows the electrical system in the multiplex signal device according to the present invention, in which a plurality of operation switches 12 provided on the steering wheel of the vehicle are used for, for example, a radio receiver, air conditioning equipment, etc. These are for various indicator lights, etc., and the signals inputted by these switches 12 are multiplexed by a multiplexing circuit 24. This multiplexing circuit 24 is composed of, for example, a microprocessor or a gate array, and this multiplexed signal output drives a plurality of light emitting elements D+ to Dn through a driving circuit 25. These light emitting elements DI to Dn are connected in parallel, and one end of the light emitting elements DI to Dn is connected to the drive circuit 2.
5, and the other end is connected to the power supply terminal 26.

5. The light signals emitted by these light emitting elements Dl-Dn are received by the light receiving element 27. The light receiving element 27 is provided on a fixed part on the vehicle body side, and the electrical signal converted by the light receiving element 27 is amplified by an amplifier 28, and further converted into an optical signal again by an optical conversion circuit 29 in this example. The signal is then received by the optical receiving circuit 31 on the load side via an optical fiber or a photocoupler. This optical signal is converted into an electrical signal by the optical receiving circuit 31, and the electrical signal is transferred to the multiplexing/demultiplexing circuit 3.
2 is separated into electrical signals corresponding to each switch 12, and the corresponding loads 33 are driven.

Structure: The electronic circuit section 34 including the multiplexing circuit 24 and the drive circuit 25 in FIG. Each operating switch 12 is attached. A light emitting ring 37 is arranged around this steering shaft 35, and as shown in FIG. A light emitting ring assembly 41 including a power supply slip ring contact 39 for the electronic circuit section 34 is provided.

A light receiving element 27 such as an odd diode or a phototransistor and an amplifier 28 are installed at a position facing the light emitting ring 37 on the steering link post side, which is a fixed part on the vehicle body side.
A conversion section 43 consisting of a light receiving module section 42 (FIG. 3) including a light receiving module section 42 (FIG. 3) and a light conversion circuit 29 is provided facing the light emitting ring assembly 37. The conversion portion 43 is fixed to the vehicle body side without contacting the shaft 35, which is provided coaxially with the shaft 35. Furthermore, on this converter 43, a sixth
As shown in the figure, a slip ring 44 is provided which makes sliding contact with the horn slip ring contact 38, and a slip ring 45 for an electronic circuit is provided coaxially with the trench. That is, these slip rings 44 and 45 are in sliding contact with the slip ring contacts 38 and 39, respectively.

An optical connector for optical fiber transmission or a connector 46 containing a photocoupler drive signal is connected to this converter 43.

Light-emitting ring The light-emitting ring 37 is composed of a plate ring-shaped wiring board 47 and a light ring-forming housing 48, as shown in FIGS. 7 to 10. The wiring board 47 has light emitting elements Dl to D4 mounted at equiangular intervals around its center, and the light emitting elements DI to D8 do not have packages such as a case or molded resin, and are made of PN junctions that constitute the light emitting elements themselves. A semiconductor, a so-called chip, has its electrodes and wiring board 4.
It is installed in direct contact with the wiring above 7.

One end surface of the ring-shaped housing 14 is in contact with the wiring board 47, and the other end surface is a ring-shaped opening 49. In this example, the ring-shaped opening 49 is closed with a plate-ring-shaped light guide plate 51. It's broken. The outer surface of this light guide plate 51 constitutes a ring-shaped light irradiation surface 52.

The light ring forming housing 48 is configured such that the light from the light emitting elements DI to Dn is directed by the light ring forming housing 48 to form one substantially uniform ring-shaped light irradiation surface 52. That is, as shown in FIG. 8, the light ring-forming housing 48 has a cross section in the direction perpendicular to the direction along the ring, and the opposing inner circumferential surfaces 49a and 49b of the housing 48 have the light emitting element D1 (i=1.
2. ... 8) From the side, as you approach the light beam 51,
The slopes are said to gradually open up to each other. These opposing inner circumferential surfaces may be curved surfaces that are convex outward from each other as shown in FIG. The element D1 may be located.

Furthermore, as shown in FIG.
As shown in the cross section in the direction of the ring, the surface on the wiring board 47 side is a slope 49c that gradually approaches the ring-shaped light irradiation surface ρ2 between adjacent light emitting elements D1.

49d is formed. wife,! 7 In the cross section of FIG. 1O, the light emitting element DI is disposed deep in the short axis direction of the semi-elliptical inner surface. Each light emitting element D1 is located deep inside the semi-spheroidal inner surface.In this way, the opposing inner peripheral surface 49a.

49b, slopes 49c, and 49d, each light emitting element Di
The light of y) is directed to form a ring-shaped irradiation surface 52. These opposing inner circumferential surfaces 49a, 49 as necessary.
b.

The slopes 49c and 49d are subjected to surface treatment such as white paint or aluminum vapor deposition to effectively reflect light from the light emitting elements Di.

In this embodiment, eight light emitting elements D1 are provided and the angle is 45°.
Although the light emitting elements are installed at intervals, the number of light emitting elements can be increased or decreased depending on the required size of the light emitting ring 37 and the required strength of the optical signal. The light ring-forming housing 48 is made - for example, as a molded product of synthetic resin material;
On the wiring board 47 side, claws 53 are integrally projected at appropriate positions on the outer peripheral edge and inner peripheral edge of the wiring board 47, and these claws 53 are connected to the wiring board 4.
7 protrudes to the opposite side of the wiring board 470 through recesses 54 provided on the outer and inner peripheral surfaces of the wiring board 47, and engages the claws 53 with the wiring board 47 to fix the wiring board 47 and the optical ring forming housing 48 to each other. Light Receiving Section As shown in FIGS. 4 and 10, a light receiving element 27 is provided closely facing the ring-shaped light irradiation surface 52 of the light emitting ring 37. The light-receiving element 27 is located at a light-converging inner surface that focuses the light from the ring-shaped light irradiation surface 52, for example, at the most recessed part of the semi-spheroidal inner surface 55. The length dl of the opening of the light converging inner surface 550 in the direction toward the ring of the light emitting ring 37 is set to be the same as or slightly smaller than the adjacent interval d2 of the light emitting elements D1. Further, if necessary, a focusing lens 56 can be inserted into the opening of the light focusing inner surface 55 as shown in FIG. It is preferable that this light converging inner surface 55 is also subjected to surface treatment using white paint or aluminum vapor deposition. Note that the light receiving module 42 includes the light receiving element 2 as described above.
7, an amplifier 28 for amplifying its output, and an optical conversion module 29 as required, and are configured as 91 semiconductor chips. It can be shielded against.

<Other Embodiments> As shown in FIG. 12, a light emitting link 37 is provided coaxially on the outer periphery of the ring 7 35, and a ring-shaped light irradiation surface 52 is formed on the circumferential surface instead of the end surface.1. This ring-shaped light irradiation surface 52
The converting section 43 may be provided on the outer periphery of the converting section 43, facing the converting section 43. In this case, a flexible substrate is used as the wiring board 47 of the light emitting ring 37. The wiring board 47 is fixed to the shaft 35 by a ring-shaped attachment part 57.

Effect> As described above, the multiplex signal transmission device for a vehicle according to this invention uses a plurality of light emitting elements Di, which form a uniform glue/glue-shaped original irradiation surface 52, Since a light receiving element is provided on the ring-shaped light irradiation surface 52, a fairly uniform optical signal can be received regardless of the rotation angle position of the steering wheel. In order to form this ring-shaped light irradiation surface 52, for example, the opposing inner circumferential surfaces 49a, 49b and slopes 49c, 49d are formed by molded resin phase products.
can be easily made into the desired shape. Furthermore, by performing surface treatment on these surfaces, it is possible to obtain strong optical signals. As in the previous example, when transmission to the load side is performed by converting it into an optical signal, a feature that is not affected by noise can be obtained. Furthermore, by forming the light condensing inner surface 55 on the light receiving element side as in the previous example, it is possible to receive a sufficiently strong optical signal even when the light receiving element 27 is located between adjacent light emitting elements.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a conventional vehicle multiplex signal transmission device, FIG. 2 is a diagram showing the relationship between the light guide ring and the light receiving element, and FIG. 3 is an electrical diagram of an example of the vehicle multiplex signal transmission device according to the present invention. A block diagram showing the system; FIG. 4 is a sectional view showing the structure of the vehicle multiplex signal transmission device according to the present invention;
Figure 5 is a cross-section mj diagram along line AA in Figure 4, and Figure 6 is B in Figure 4.
A sectional view taken along the line B, and FIG. 7 is an exploded first perspective view of the light emitting ring 37.
Figure 8 is a cross-sectional view perpendicular to the light emitting ring, Figure 9 is a cross-sectional view showing other examples, Figure 10 is a cross-sectional view of the ring of the light emitting unit and the light receiving module, and Figure 11 is the light receiving section. FIG. 12 is a sectional view showing the structure of another example of the vehicle multiplex signal transmission device according to the present invention. 12; switch, 24: multiplexing circuit, 25: drive circuit,
27: Light-receiving element, 32: Multiplexing/demultiplexing circuit, 37: Light-emitting ring, 47: Wiring board, 48: Optical ring forming/using, 52: Ring-shaped light irradiation surface, 49a to 49d: Inner surface for light directionality, 55 : Focusing curved surface, D, to Dnn dual optical element Patent applicant: Yazaki Sogyo Co., Ltd. Agent Takashi Kusano yP 5 Figure 6 Figure 27 78 Fork # 10 Fork Bowl 11 Ward 71712 Katana 650

Claims (1)

[Claims] (1) A multiplex transmission circuit that multiplexes signals corresponding to multiple switch inputs mounted on the steering wheel and generates the multiplexed signal, and multiple light emitting elements that are simultaneously driven by the multiplexed signal. , a wiring board provided on a rotating part that rotates integrally with the steering shaft, on which chips of the plurality of light emitting elements are attached at approximately equal angular intervals on a circumference centered on the shaft and shaft of the steering handle; The light from each of the light emitting elements is directed to form a ring-shaped light irradiation surface that is generally uniform as a whole, and a light ring forming housing provided on the wiring board is closely opposed to the ring-shaped irradiation surface. A multiplex signal transmission device for a vehicle, comprising: a light receiving element provided on a fixed part on the vehicle body; a demultiplexing circuit that amplifies and shapes the signal received by the light receiving element; and demultiplexes the multiplexed signal.