JP2000133399A - Rotary connecting device and terminal welding method suitable for its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To downsize a casing by providing a winding portion wound orthogonally to a rotation central axis and taking-out portions reversely provided in parallel with the rotation central axis, providing the winding portion with a cable stored in an inner space of the casing formed from a fixing member and a rotation member, and taking out the taking-out portions from the casing in a circular arc shape around the rotation central axis. SOLUTION: This rotation connecting device 100 is provided with a fixing member 110 and a rotation member 120 which constitute a casing and a cable 130. The cable 130 is constituted with a winding portion 131 wound orthogonally to a rotation central axis L, taking-out portions 132, 133 provided reversely projecting in parallel with the rotation central axis L, and terminal members 140, 141 for connecting the winding portion 131 with the taking-out portions 132, 133. The taking-out portions 132, 133 are taken out from the casing body in a bent state in a circular arc shape around the rotation central axis L. Thus, even when number of wires of the cable 130 increases, the outer diameter of the casing is not required to be increased.

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 used for electrical connection between parts that rotate relative to each other in an automobile, a home electric appliance, or the like.

[0002]

2. Description of the Related Art FIG. 6 shows a general structure of a steering wheel mounting portion of an automobile. Steering shaft 2
Are rotatably supported by the vehicle body side bracket 1.
A switch device 3 and a rotary connection device 4 are provided on the vehicle compartment side of the bracket 1. The tip of a portion of the steering shaft 2 that protrudes through the switch device 3 and the rotary connection device 4 is provided with the steering shaft 2.
The steering wheel 6 is mounted so as to rotate integrally with the steering wheel. The steering wheel 6 is provided with electrical components 7 such as a horn switch and an airbag as required. The switch device 3 is integrally assembled with switches such as a turn signal lamp and a wiper, and operation levers 8 and 9 for switching the switches are mounted on the left and right side surfaces, respectively.

[0003] The rotary connection device 4 is a device for electrically connecting an electric component 7 that rotates with the steering wheel 6 and a circuit on the body side. The configuration of the rotary connection device 4 generally used conventionally will be described with reference to FIGS. 7 to 9.

The rotary connection device 4 includes a cylindrical fixed member 10 and an annular rotary member 11 which constitute a housing, and a cable 13.
Is provided. The fixing member 10 is fixed to the vehicle body side bracket 1. The rotating member 11 is rotatably fitted to the fixed member 10 and rotates integrally with the steering wheel 6. The rotating member 11 is provided with a tubular portion 12 that penetrates the fixing member 10 at the center thereof, and the tubular portion 12 is fitted with the rotating member 11 fitted to the fixing member 10.
When the C-ring 21 is engaged with the rotating member 11, the rotating member 11 and the fixed member 10 cannot be separated. Inside the fixing member 10,
A lubricating sheet 22 for reducing friction between the cable 13 and the fixing member 10 is provided.

[0005] The cable 13 comprises a winding part 14 and take-out parts 17 and 18, and terminal members 15 and 16 connecting the winding part 14 and the take-out parts 17 and 18. For example, a flexible flat cable (FFC) or a flexible
A print circuit (FPC) or the like is used.
The winding portion 14 of the cable 13 is housed in an annular space 12 formed between the fixed member 10 and the rotating member 11, and the take-out portions 17 and 18 are respectively parallel to the rotation center axis of the rotating member 11. And protrude in opposite directions. For example, L-shaped bus bars 25 as shown in FIG. 9 are arranged inside the terminal members 15 and 16, and the conductors of the winding portion 14 and the take-out portions 17 and 18 which are arranged at substantially right angles to each other. The conductors are electrically connected to each other. Further, connectors 19 and 20 are connected to the take-out portions 17 and 18, respectively.

[0006] By connecting the connector 19 to the connector 23 provided on the vehicle body side bracket 1 and connecting the connector 20 to the connector 24 provided on the electrical component 7,
A control circuit (not shown) provided on the vehicle body is electrically connected to the electrical component 7.

[0007]

As apparent from FIGS. 7 and 8, the cable 1 in the conventional rotary connection device 4 is shown.
The three take-out portions 17, 18 are arranged in a straight line.
However, the number of circuits increased due to the enhancement of the electrical components 7,
The number of electric wires of the cable 13 also tends to increase. In the configuration in which the take-out portions 17 and 18 of the cable 13 are arranged in a straight line as described above, the width of the cable 13 increases as the number of circuits or the number of electric wires increases.
The width of 7, 18 is also increased.

In particular, the take-out portion 1 inside the cable 13
8 is provided in the vicinity of the cylindrical portion 12 of the rotating member 11, so that when the width of the cable 13 and the take-out portions 17 and 18 increases, the outer diameters of the fixed member 10 and the rotating member 11, particularly the rotating member 11 The outer diameter of the cylindrical portion 12 must be increased, and it is difficult to reduce the size of the rotary connection device.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and has as its object to provide a rotary connection device capable of increasing the number of circuits and reducing the size of a housing.

[0010]

In order to achieve the above object, a rotary connection device according to the present invention comprises a fixed member and a rotary member which are relatively rotatable about a rotation center axis, and which is orthogonal to the rotation center axis. And a take-out portion provided substantially parallel to the rotation center axis and in opposite directions to each other, and at least the winding portion is formed by the fixed member and the rotating member. And a cable housed in an internal space of the housing, wherein at least one of the take-out portions is taken out of the housing so as to form an arc around the rotation center axis. .

In the above configuration, the cable may be a flexible flat cable or a flexible printed circuit in which a plurality of electric wires are arranged substantially in parallel.

Further, the cable may be formed by winding a single member, and bending both ends of the member at substantially right angles to the winding portion.

[0013] Alternatively, in the cable, the electric wire of the winding portion and the electric wire of the take-out portion, each of which is formed of a separate member, are connected by a substantially L-shaped bus bar. One of the two arms constituting the substantially L-shape is substantially L
The shape may be an arc on a plane perpendicular to the plane forming the character.

The welding method according to the present invention is a method for welding a bus bar and an electric wire in the rotary connection device, wherein the first member having an arc-shaped concave surface and the arc-shaped convex surface having a smaller radius than the arc-shaped concave surface are provided. A bus bar and the electric wire in a state in which electric wires exposed from a plurality of bus bars and cables are arranged at predetermined intervals between the arc-shaped concave surface and the arc-shaped convex surface. And welding.

In the above method, it is preferable that the welding is any one selected from ultrasonic welding, resistance welding, and laser welding.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a rotary connection device of the present invention and a welding method suitable for manufacturing the same will be described with reference to the drawings. FIG. 1 shows a rotary connection device 10 according to the present embodiment.
FIG. 2 is an exploded perspective view showing the configuration of the apparatus, and FIG. 2 is a perspective view showing an assembled state thereof. FIG. 3 is a perspective view showing a connection state between the electric wire of the cable and the bus bar.

As shown in FIGS. 1 and 2, the rotary connection device 100 according to the present embodiment includes a cylindrical fixed member 110 and an annular rotary member 120 which constitute a housing, as in the conventional example.
A cable 130 is provided. The fixing member 110 is fixed to the vehicle body side bracket 1 (see FIG. 6). The rotating member 120 is rotatably fitted to the fixed member 110, and rotates integrally with the steering wheel 6. The rotating member 120 is provided with a cylindrical portion 121 that penetrates the fixing member 110 at the center thereof, and the C ring 107 is attached to the cylindrical portion 121 in a state where the rotating member 120 is fitted to the fixing member 110. When engaged, the rotating member 120 and the fixed member 110 cannot be separated. Inside the fixing member 110, a slip sheet 105 for reducing friction between the cable 130 and the fixing member 110 is provided.

The cable 130 has a winding portion 131 wound in a direction perpendicular to the rotation center axis L for rotating the fixed member 110 and the rotating member 120 relatively to each other. It is composed of take-out portions 132 and 133 provided so as to protrude in opposite directions, and terminal members 140 and 141 connecting the winding portion 131 and the take-out portions 132 and 133. Winding part 131 and take-out part 13
As 2,133, for example, a flexible flat cable (FFC), a flexible print circuit (FPC), or the like is used. The winding part 131 of the cable 130 is housed in an annular space 111 formed between the fixed member 110 and the rotating member 120. Unlike the conventional example, the take-out portions 132, 1 of the cable 130
33 is taken out of the housing in a state of being bent in an arc shape so that those electric wires are arranged on the circumference of a circle centered on the rotation center axis L. Since the FFC and FPC have flexibility in the direction in which the electric wires are arranged and in the direction orthogonal thereto, they are suitable for being wound in an annular shape or bent in an arc shape.

Inside the terminal members 140 and 141, for example, L-shaped bus bars 143 as shown in FIG. 3 are arranged, and the conductor 134 and the take-out portion of the winding portion 131 which are arranged at substantially right angles to each other. 132 and 133 are electrically connected to the conductors 135, respectively. The bus bar 143 is shown in FIG.
It is straight in the middle X direction, but bent in an arc shape in the Y direction. The radius of curvature of the arc-shaped portion of the bus bar 143 housed inside each of the terminal members 140 and 141 is different, and the radius of curvature of the terminal member 141 arranged closer to the rotation center axis L is smaller.

Further, the fixing member 110 and the rotating member 120
Are engaged with housings of the terminal members 140 and 141, respectively, and are provided with engaging portions 1 for holding the terminal members 140 and 141, respectively.
12, 122 are formed. Terminal members 140, 14
The shape of the case 1 and the direction perpendicular to the rotation center axis L of each of the engagement portions 112 and 122 is an arc shape centered on the rotation center axis L.

Take-out portions 132, 13 of cable 130
3 are connected to connectors 150 and 151. By connecting the connector 150 to the connector 23 provided on the bracket 1 on the vehicle body side (see FIG. 6) and connecting the connector 151 to the connector 24 provided on the electrical component 7, the control circuit ( (Not shown) and the electrical component 7 are electrically connected. Note that the connectors 150, 1
The terminal 51 is arranged linearly as in the conventional example, but is not necessarily limited to this. The terminals of the connectors 150 and 151 may also be arranged in an arc shape.

FIG. 4 shows a method of welding the electric wires 134 and 135 of the winding part 131 and the take-out parts 132 and 133 of the cable 130 to the bus bar 143. In FIG. 4, (a) shows the take-out units 132 and 133 and the bus bar 14.
3A and 3B are diagrams illustrating a shape and a welding state of a welding head for welding the first and second welding heads 3 and 3, and FIG.
FIG. 4 is a diagram showing a shape and a welding state of a welding head for welding the welding head and the welding head. In any case, the welding portions of the plurality of electric wires 134 and 135 and the bus bar 143 are simultaneously welded.

As shown in FIG. 4A, the first member 200
Has an arcuate concave surface 201, and the second member 210 has an arcuate convex surface 211. The first member 200 and the second member 210 constitute a welding head. The term “welding head” as used herein is a broad concept including a positioning jig.

The first member 200 and the second member 210 are each linear in a direction perpendicular to the plane of the paper. The radius of curvature R1 of the arcuate concave surface 201 of the first member 200 is almost equal to the radius of curvature of the take-out portions 132 and 133 of the cable 130, and the radius of curvature R2 of the arcuate convex surface 211 of the second member 210 is slightly smaller. Small (R1> R2).

The same applies to the case shown in FIG.
The member 220 has an arcuate concave surface 221, the second member 230 has an arcuate convex surface 231, and the first member 220 and the second member 23
0 constitutes a welding head. First member 220 and second member
Each of the members 230 is linear in a direction perpendicular to the paper surface. Further, the radius of curvature R3 of the arcuate concave surface 221 of the first member 220 is determined by the take-out portions 132, 1
The radius of curvature of the arc-shaped convex surface 231 of the second member 230 is slightly smaller (R3> R4, R4 ≒ R2).

As described above, since the distance from the rotation center axis L, that is, the radius of curvature of the take-out position is different between the take-out portions 132 and 133 of the cable 130, the take-out portions 132 and 133 have circular shapes. It is preferable to prepare dedicated welding heads having different curvature radii of the arc-shaped concave portions 201 and 221 and the arc-shaped convex portions 211 and 231.

As a welding method, any of known welding methods such as ultrasonic welding, resistance welding, and laser welding may be used. First, the take-out portions 132 and 133 of the cable 130
When the electric wire 135 and the bus bar 143 are respectively overlapped, the arc-shaped concave surface 201 of the first member 200 and the second member 21
It is sandwiched between the 0 and the arc-shaped convex surface 211. The electric wire 135 and the bus bar 143 may be upside down.

For example, in the case of ultrasonic welding or resistance welding, the first
Ultrasonic vibration and current are supplied to the welding portion between the electric wire 134 and the bus bar 143 via the member 200 and the second member 210. On the other hand, in the case of laser welding, the first member 200 or the second member
A laser beam is applied to a welding portion between the electric wire 134 and the bus bar 143 from a laser oscillation device (not shown) provided near any one of the members 210. As a result, a plurality of electric wires 1
34 and the bus bar 143 can be welded at the same time, and the bus bar 143 can be kept parallel.

Next, in a state where the electric wire 134 of the winding part 131 of the cable 130 and the bus bar 143 are overlapped,
It is sandwiched between the arcuate concave surface 221 of the first member 220 and the arcuate convex surface 231 of the second member 230. In addition, the electric wire 134
Upside down of the bus bar 143 may be reversed. In this state, ultrasonic vibration, electric current, laser beam, and the like are supplied to the welding portion between the electric wire 134 and the bus bar 143, and the two are welded.

The electric wire 134 of the winding part 131 and the welding and taking-out parts 132 and 133 of the bus bar 143
35 and the bus bar 143 may be simultaneously welded.

In the above embodiment, the electric wire 134 of the winding portion 131 of the cable 130 and the electric wire 135 of the take-out portions 132 and 133 are connected by the substantially L-shaped bus bar 143. However, the present invention is not limited to this. Not something. For example, as shown in FIG.
Near both ends of the wire is approximately 45
The take-out portions 132 and 133 may be bent so as to be appropriate and opposite to each other. According to this configuration,
The terminal members 140 and 141 become unnecessary, and the electric wires 13
4,135 and the welding process of bus bar 143 become unnecessary.
However, this configuration is limited to a case where insulation failure such as peeling of the insulation material at the bent portion does not occur.

Further, in the above embodiment, the cable 13
The two take-out portions 132 and 133 of 0 are configured to be taken out in an arc shape centered on the rotation center axis L. However, the present invention is not limited to this, and at least one of them is particularly close to the rotation center axis L. That is, it may be configured such that only the take-out portion 133 located on the inner side with a small radius of curvature is taken out in an arc shape.

[0033]

As described above, according to the rotary connection device of the present invention, the fixed member and the rotary member rotatable relative to the rotation center axis are wound with the winding member in a direction perpendicular to the rotation center axis. Winding portion and a take-out portion provided substantially parallel to the rotation center axis and in opposite directions to each other, and housed in an internal space of a housing in which at least the winding portion is formed by a fixed member and a rotating member. And at least one of the take-out portions is taken out from the housing so as to form an arc centered on the rotation center axis, so that the outer peripheral portion of the fixed member and the rotating member constituting the housing is provided. The cable can be taken out along with the cable, and the size of the cable take-out portion has a margin. As a result, it is not necessary to increase the outer diameter of the housing even when the number of wires of the cable increases, as compared with the case where the cable outlet is arranged linearly as in the conventional example. Conversely, when the number of electric wires of the cable does not increase, the outer diameters of the fixing member and the rotating member constituting the housing can be reduced, and the rotary connection device itself can be reduced in size.

Further, by using either a flexible flat cable or a flexible printed circuit in which a plurality of electric wires are arranged substantially in parallel as a cable, since these cables have flexibility, Without adopting a simple configuration, the electric wires near both ends of the cable can be easily held in an arc shape substantially parallel to the outer peripheral portion of the housing.

As a cable, a single member is wound, and the vicinity of both ends of the member is bent at substantially right angles with respect to the winding portion, respectively, thereby forming a substantially L-shaped bus bar as shown in FIG. This eliminates the necessity of a terminal member that uses a rotary connection device, simplifies the configuration of the rotary connection device, and makes it possible to reduce the size of the rotary connection device itself.

Alternatively, as the cable, the electric wire of the winding portion and the electric wire of the take-out portion, each of which is made of a separate member, are connected by a substantially L-shaped bus bar, and the substantially L-shaped bus bar is connected to the substantially L-shaped bus bar. By making one of the two arms constituting an arc on a surface orthogonal to the surface forming a substantially L-shape, even when the cable itself cannot be bent, the cable take-out portion is formed in an arc shape. Can be arranged.

As a method for welding the bus bar and the electric wire, a welding head is constituted by a first member having an arc-shaped concave surface and a second member having an arc-shaped convex surface having a smaller radius than the arc-shaped concave surface. By welding the bus bar and the electric wire in a state where the electric wires exposed from the plural bus bars and the cables are arranged at a predetermined interval between the concave surface and the arc-shaped convex surface, the plural bus bars and the electric wire are welded at the same time. It is possible to do. In particular, by using any one selected from ultrasonic welding, resistance welding, and laser welding as a welding method, it is possible to easily and reliably weld a terminal member, which is a minute welding portion, to an electric wire.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a configuration of an embodiment of a rotary connection device of the present invention.

FIG. 2 is a perspective view showing an assembled state of the embodiment.

FIG. 3 is a perspective view showing a connection state between an electric wire of a cable and a bus bar in the embodiment.

4A and 4B are diagrams illustrating a method of welding each electric wire of a cable and a bus bar in the embodiment, and FIG. 4A is a diagram illustrating a shape and a welding state of a welding head for welding a take-out portion and a bus bar. FIG. 4B is a diagram showing a shape and a welding state of a welding head for welding a winding portion and a bus bar.

FIG. 5 is a perspective view showing the configuration of another embodiment of the rotary connection device of the present invention.

FIG. 6 is an exploded side view of a steering wheel mounting portion of the automobile.

FIG. 7 is an exploded perspective view of a conventional rotary connection device.

FIG. 8 is an assembled perspective view of a conventional rotary connection device.

FIG. 9 is a view showing a welding structure of an electric wire and a bus bar in a conventional cable.

[Explanation of symbols]

 100: Rotary connection device 105: Slippery sheet 107: C-ring 110: Fixing member 111: Annular space 112: Engaging part 120: Rotating member 121: Cylindrical part 122: Engaging part 130: Cable 131: Winding Parts 132, 133: Take-out parts 134, 135: Electric wires 140, 141: Terminal members 143: Bus bars 150, 151: Connectors

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Atsuhiko Fujii 1-7-10 Kikuzumi, Minami-ku, Nagoya-shi, Aichi F-term in Harness Research Institute, Ltd. (Reference) 3D030 DB22 DB25 5E085 BB05 CC06 DD03 EE06 HH12 JJ47

Claims (6)

[Claims] 1. A fixed member and a rotating member which are relatively rotatable about a rotation center axis, a winding part wound in a direction perpendicular to the rotation center axis, and substantially parallel to the rotation center axis, and A cable housed in an internal space of a housing formed by the fixing member and the rotating member, the cable having at least one take-out part provided in a direction opposite to each other, At least one of which is taken out of the housing so as to form an arc centered on the rotation center axis. 2. The rotary connection device according to claim 1, wherein the cable is one of a flexible flat cable and a flexible printed circuit in which a plurality of electric wires are arranged substantially in parallel. 3. The cable according to claim 1, wherein a single member is wound around the cable, and both ends of the member are bent substantially at right angles to the winding portion. Rotary connection device. 4. The cable connects an electric wire of the winding portion and an electric wire of the take-out portion, each of which is formed of a separate member, with a substantially L-shaped bus bar. 3. The rotary connection device according to claim 1, wherein one of the two arms forming the substantially L-shape has an arc shape on a surface orthogonal to a surface forming the substantially L-shape. 5. A welding head comprising a first member having an arc-shaped concave surface and a second member having an arc-shaped convex surface having a smaller radius than the arc-shaped concave surface, wherein the welding head comprises the arc-shaped concave surface and the arc-shaped convex surface. The busbar and the electric wire are welded in a state where the electric wires exposed from the plurality of busbars and the cable are arranged in an overlapped manner at predetermined intervals.
A method for welding a rotary connection device as described in the above. 6. The terminal welding method according to claim 5, wherein the welding is selected from ultrasonic welding, resistance welding, and laser welding.