JPH1116653A - Rotational connecting device for steering wheel attaching portion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize the structure of a rotational connecting device provided with a steering quantity detector and reduce the number of component parts and the number of assembling man-hours. SOLUTION: In this rotational connecting device, a case 2 fixed onto a body side and a rotor 3 fixed to a steering wheel side are combined in such a manner as to be freely rotated relative to each other. An electric wiring on the body side is connected to an electric wiring on the steering wheel side via a cable 6 contained inside the case 2. In this case, a circuit board 9 incorporating therein an electronic circuit for transmitting signals output from switches disposed in the steering wheel at the same time when the body side is attached to the rotor 3, and further, perforations 14 for detecting a steering quantity of the steering wheel are formed integrally with the circuit board 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary connection device provided on a steering wheel mounting portion of an automobile, for connecting electric wiring on a body side to electric wiring on a steering wheel side.

[0002]

2. Description of the Related Art As shown in FIGS. 3 and 4, for example, a steering wheel mounting portion of an automobile has a steering shaft 21 rotatably supported in a steering column 20 fixed to a body. A steering shaft 2 which projects upward through a switch device 22 provided on the upper side and a rotary connection device 1
A steering wheel 23 is attached to the tip of the steering wheel 1 so as to rotate integrally with the shaft. Electric components 2 such as a horn and an airbag are provided on the steering wheel 23.
4 will be equipped as needed. The switch device 22 is integrally assembled with switches such as a turn signal lamp and a wiper, and operation levers 26 and 27 for switching the switches are mounted on left and right side surfaces, respectively. The rotary connection device 1 is a device for electrically connecting the electric component 24 that rotates with the steering wheel 23 and an electric circuit on the body side.
The conventional one has, for example, a configuration as shown in FIG.

[0005] A rotary connection device 1 shown in FIG. 5 includes a case 2 fixed to a switch device 22 and a steering wheel 2.
3 is combined with the rotating body 3 so as to be rotatable relative to each other, and a space 5 formed between the rotating bodies 3 and 2 is formed.
The cable 6 electrically connected to the electric circuit on the body side and the wiring of the electrical component 24 is housed in a spirally wound state. The spiral cable 6 is tightened and unwound according to the rotation of the steering wheel 23, so that the electric circuit on the body side and the wiring of the electrical component 24 are maintained in an electrically connected state.

[0004] The rotation connection device 1 may be provided with a steering amount detecting device for detecting the steering amount of the steering wheel 23. In that case, a disk 28 having a plurality of perforations 14 formed at equal intervals on the outer peripheral portion is attached to the lower end of the rotating body 3, and a photo sensor or the like that detects perforations at a position where the perforations 14 of the disk 28 pass is used. In general, the sensor 15 is arranged.

[0005]

The cable 6 of this type of rotary connection device has a band shape in which a plurality of electric wires are arranged side by side in the axial direction of the steering shaft 23, that is, vertically. As the number increases, the vertical width of the cable 6 increases, and the vertical dimension of the rotary connection device 1 itself increases. For this reason, when the number of the electrical components 24 provided on the steering wheel 23 is large, it is not easy to secure a space for assembling the enlarged rotary connection device 1.

In the case where a steering amount detecting device is provided in the rotary connection device 1, as shown in FIG.
In order to attach the disk 28 on which the disk 4 is formed to the lower end portion of the rotating body 3, it is necessary to provide a space for accommodating the disk 28 between the case 2 of the rotary connection device and the switch device 22. Since the connecting device 1 must be disposed entirely upward, there is a disadvantage that the mounting position of the steering wheel 23 is increased. Further, in this case, there is a problem that the number of parts and the number of assembly operations are increased.

SUMMARY OF THE INVENTION In view of the above circumstances, it is an object of the present invention to reduce the size of a rotary connection device provided with a steering amount detection device and to reduce the number of parts and the number of assembly operations.

[0008]

In order to achieve the above object, the present invention provides a case wherein a case fixed to a body and a rotating body fixed to a steering wheel are combined so as to be relatively rotatable relative to each other, In the rotation connection device of the steering wheel mounting portion in which the electric wiring and the electric wiring on the steering wheel side are connected via a cable housed in the case, signals from switches provided on the steering wheel are collectively sent to the body side. A circuit board on which an electronic circuit for transmission is mounted is attached to the rotating body, and perforations for detecting a steering amount of steering are formed integrally with the circuit board.

According to this structure, the number of conductors of the cable is reduced by attaching the circuit board on which the electronic circuit for transmitting the signals from the switches provided on the steering wheel to the body side together is mounted on the rotating body. And the axial dimension of the steering shaft of the rotary connection device can be reduced. Further, by forming perforations on the rotating board for detecting the steering amount of the steering wheel, the number of parts can be reduced.

Although the type of the circuit board is not particularly limited, the circuit board can be made thinner and lighter by employing an FPC in which a conductor portion is formed by etching a substrate in which a resin plate is coated with a metal film.

Further, as a specific example of the structure in which the perforation is formed integrally with the circuit board, the perforation may be formed by etching the circuit board, or may be provided integrally with the periphery of the circuit board. Perforations may be formed by punching a metal plate to be formed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described with reference to FIGS.

The rotary connection device 1 includes a switch device 22
And a steering wheel 23 (see FIGS. 3 and 4), comprising a case 2 fixed to a switch device 22 and a rotating body 3 attached so as to rotate integrally with the steering wheel 23. ing. The case 2 has a circular container shape with a circular hole 2a formed in the bottom and opening upward. The rotating body 3 has a substantially annular top plate 3a formed at the upper end of a cylindrical main body, and further engages with an engagement hole (not shown) provided in the steering wheel 23 on the upper surface of the top plate 3a. The pin 3b is provided integrally. The lower end of the main body of the rotating body 3 is rotatably fitted in the circular hole 2a of the case, and the upper and lower parts of the case 2 are rotatable relative to each other with the top plate 3a of the rotating body closed. Be combined. The steering shaft 21 is inserted inside the main body of the rotating body 3.

A flexible cable 6 is spirally housed in a space 5 formed between the case 2 and the rotating body 3. In the cable 6, a plurality of electric wires 6a are arranged and arranged on a plane intersecting the winding surface.
The surface is flat and has a wide band shape in the direction in which the wires are arranged. A female terminal connector 7 is connected to an outer end of each electric wire 6 a of the cable 6, and the connector 7 is accommodated in a connector accommodating portion 2 b formed on an outer peripheral portion of the case 2. The inner end of each electric wire 6a is connected to a circuit board 9 described later.
Terminal 9c.

A disk-shaped circuit board 9 incorporating a multi-processing electronic circuit for transmitting signals from switches provided on the steering wheel to the body side is mounted on the upper side of the rotating body 3. . The circuit board 9 is made of an FPC in which a conductor portion is formed by etching a substrate in which a metal plate is coated on a resin plate. Rotating body 3
When the circuit board 9 is mounted on the drive pin 3b
Are inserted through the pin holes 9a of the circuit board 9,
9 rotates integrally. The inner end of each electric wire 6a of the cable 6 is pulled out to the upper side of the circuit board 9 through the electric wire insertion hole 3c of the rotating body 3 and the electric wire insertion hole 9b of the rotating board 9, and the terminal 9c provided on the upper surface of the circuit board 9 Are connected by welding or the like.

As shown in FIGS. 3 and 4, the female terminal connector 7 is connected to a connector 11 connected to an end of a wire harness 10 connected to an electric circuit on the body side. By connecting the end of the wiring 12 to the terminal 9 d of the circuit board 9 by welding or the like, the electric circuit on the body side and the electric component 24 are electrically connected. Since a multi-processing electronic circuit for collectively transmitting signals from the switches of the electric component 24 to the body side is provided between the electric component 24 and the cable 6, the number of electric wires of the cable 6 can be reduced.

A perforation 14 for detecting the amount of steering is provided on the outer peripheral portion of the circuit board 9.
Are formed at equal intervals. The perforation 14 in the illustrated example is formed by directly etching the peripheral portion of the circuit board 9. Note that a metal plate may be integrally attached to a peripheral portion of the circuit board 9 and the perforation 14 may be formed on the metal plate by punching.

A sensor 15 for detecting the passage of the perforations 14 is attached to the connector housing 2b. The sensor 15 in the illustrated example is a photo sensor, and is arranged so that the perforations 14 pass between the light projecting unit 15a and the light receiving unit 15b. The photo sensor used as the sensor 15 may be of a transmission type or a reflection type, and in some cases, an appropriate sensor other than the photo sensor may be used. Sensor 15
Is connected to a control device (not shown) by wiring, and the detection result of the sensor 15 is sequentially transmitted to the control device.

According to the rotary connection device of this embodiment, the cable 6 is wound around the main body of the rotating body 3 when the steering wheel 23 is rotated in one direction to the left and right, and when the steering wheel 23 is rotated in the opposite direction, the cable 6 is connected to the side wall of the case 2. It is rewound to crawl along. Thus, the steering wheel 23
The cable 6 is tightened and rewound in accordance with the rotation of, so that the electric circuit on the body side and the electric component 24 are maintained in an electrically connected state.

When the steering wheel 23 is rotated, each time the perforation 14 passes through the sensor 15, a pulse signal is sent from the sensor to the control device. Then, the steering amount is calculated from the number of pulses, that is, the number of perforations that have passed.
Further, it is also possible to calculate the steering operation speed from the change in the steering amount per unit time.

[0021]

As described above, the rotary connection device of the present invention
Since the electronic circuit for transmitting signals from the switches provided on the steering wheel to the body side collectively is provided on the switch side rather than the cable, the number of wires of the cable can be reduced, and the rotational connection can be made. It is possible to reduce the dimension of the steering shaft of the device in the axial direction, and to reduce the number of parts and the number of assembling steps by integrally forming perforations for detecting the steering amount of the steering on the rotating substrate. Can be.

In the present invention, when a circuit board is manufactured by a method in which a conductor portion is formed by etching a substrate in which a metal plate is coated on a resin plate, an effect that the circuit board can be made thin and lightweight can be obtained.

If the circuit board is etched to form perforations, or if a perforation is formed by punching a metal plate provided integrally with the periphery of the circuit board, the perforations can be formed. The effect of being easy is also obtained.

[Brief description of the drawings]

FIG. 1 is an assembled perspective view of a rotary connection device.

FIG. 2 is an exploded perspective view of the rotary connection device.

FIG. 3 is a front view of a steering wheel mounting portion of the automobile.

FIG. 4 is an exploded view of a steering wheel mounting portion of the automobile.

FIG. 5 is a sectional view of a conventional rotary connection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotary connection device 2 Case 3 Rotating body 6 Cable 9 Circuit board 14 Perforation 15 Photosensor

Claims (3)

[Claims] 1. A case fixed to a body side and a rotating body fixed to a steering wheel side are combined so as to be relatively rotatable with each other, and the electric wiring on the body side and the electric wiring on the steering wheel side are provided in the case. In the rotation connection device of the steering wheel attachment portion connected via the accommodated cable, the circuit board on which an electronic circuit for transmitting signals from switches provided on the steering wheel to the body side in a lump is rotated. A rotation connecting device for a steering wheel mounting portion, wherein the device is attached to a body and perforations for detecting a steering amount of a steering are formed integrally with the circuit board. 2. The rotary connection device for a steering wheel mounting portion according to claim 1, wherein the circuit board is formed by etching a substrate in which a metal plate is coated on a resin plate to form a conductor portion. . 3. The device according to claim 2, wherein the perforations are formed by etching the circuit board. 3. The circuit board according to claim 1, wherein the perforations are formed by punching a metal plate provided integrally with a peripheral portion of the circuit board.
4. The rotation connection device for a steering wheel mounting portion according to 4.