JP2000068020A - Rotation connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotation connector that prevents vibration of a guide member for reversing a belt-shaped transmission line in a U-shape and silently works. SOLUTION: This connector 1 is constituted by having first and second cases 2, 3 that are combined relatively rotatably and have an annular space S inside, and a belt-shaped transmission line 4 that is fixed to the first case 2 at its one end and to the second case 3 at the other end and is stored by being wound in the annular space S into a spiral shape. The belt-shaped transmission line 4 is rewound at its intermediate part into a U-shape, and through the rewound belt-shaped transmission line, a plurality of rollers 7 are rotatably and movably circumferencially supported in an annular space and a C-ring-shaped guide member 5 having a collar 6a pinchingly held in the engagement portions of the both cases 2, 3 is arranged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary connector for transmitting an electric signal, an optical signal or electric power between a rotating member and a fixed member which rotate relatively.

[0002]

2. Description of the Related Art As a transmission device for transmitting an electric signal, an optical signal, electric power, or the like between a rotating member and a fixed member which rotate relative to each other, for example, a cable reel disclosed in Japanese Patent Application Laid-Open No. 4-3280071 is known. ing. This cable reel is provided with a U-shaped inversion section in the middle between a fixed body, a movable body rotatably mounted on the fixed body, and an annular space formed by the fixed body and the movable body. And a flexible cable which is wound around and housed in the inner and outer cylindrical portions in opposite directions and connects the fixed body and the movable body. The cable reel has a guide member provided with a plurality of rollers on the inner and outer circumferences in a C-ring shape in the space such that the U-shaped inverted portion is hooked on the C-ring-shaped end portion. The plurality of rollers press and urge the flexible cable over substantially the entire outer peripheral surface of the inner cylindrical portion and the inner peripheral surface of the outer cylindrical portion by the elastic member.

For this reason, in the above cable reel, the winding and unwinding of the flexible cable into the inner tube portion and the outer tube portion are guided by the guide member, and a U-shaped inverted portion is formed in the space. It moves smoothly, and the relative rotation between the fixed body and the movable body is achieved.

[0004]

By the way, when the cable reel is used as a connector for, for example, being provided in a steering device of an automobile and initiating an airbag, when the vibration is caused by the running of the automobile, the cable reel described above is used. The guide member may move in the rotation axis direction and collide with the inner wall of the fixed body or the movable body, generating an unpleasant collision sound.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a rotary connector that operates quietly by preventing vibration of a guide member that reverses a belt-shaped transmission line into a U-shape.

[0006]

According to the present invention, in order to achieve the above object, a first case and a second case, which are combined with each other so as to be rotatable relative to each other and have an annular space formed therein, and one end of which is connected to the first case. And a rotary connector provided with a band-shaped transmission line which is fixed to the second case at the other end and which is spirally wound and housed in the annular space. A plurality of rollers are rotatably supported in the annular space in the circumferential direction, rotatably support a plurality of rollers, and are engaged between the two cases. And a C-ring-shaped guide member having a flange portion sandwiched between the guide members is arranged.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a rotary connector according to the present invention will be described below in detail with reference to FIGS. Here, FIG. 2 is a cross-sectional view of the rotary connector cut along a plane perpendicular to the rotation axis and viewed from below. As shown in FIG. 1, the rotary connector 1 includes a rotary case 2, a fixed case 3, a flat cable 4, and a guide member 5, and the rotary case 2 and the fixed case 3 are formed of a synthetic resin such as polyacetal or polybutylene terephthalate. ing.

The rotating case 2 has an inner cylindrical shaft portion 2a and an upper flange 2b, and one end (inner end) of a flat cable 4 wound spirally is fixed. As shown in FIG. 2, the inner cylindrical shaft portion 2a and the upper flange 2b have stepped portions 2c and 2d formed on the lower outer periphery and the outer peripheral edge, respectively. As shown in FIGS. 1 and 2, the fixed case 3 has an outer cylindrical portion 3a, an upper flange 3b, and a lower flange 3c, is relatively rotatably combined with the rotating case 2, and has a flat cable 4 therein.
Is formed in an annular space S. The other end (outer end) of the flat cable 4 is fixed to the fixed case 3.
The upper flange 3b engages with a step 2d formed on the outer peripheral edge of the upper flange 2b of the rotating case 2. Lower flange 3c
Engages with a step 2c of the inner cylinder shaft 2a by sandwiching a flange 6a of the guide ring 6 described below between the inner peripheral edge and the step 2c.

The flat cable 4 is, for example, a plurality of flat electric conductors or optical fibers or a combination thereof, arranged in parallel at a desired arrangement pitch, and covered with a flexible band-like transmission covered with an electrically insulating coating. The wire is spirally wound and housed in an annular space S formed by the rotating case 2 and the fixed case 3. At this time, the flat cable 4 is wound back into a U-shape in the middle as shown in FIG. 2, and the guide member 5 is arranged between the flat cable 4 thus wound.

[0010] The guide member 5 has a flange portion 6a.
A plurality of rolls 7 are rotatably supported by a ring-shaped guide ring 6. The guide ring 6 has a flange 6a formed radially inward via a step, and as shown in FIG.
The flange 6a is sandwiched between the step 2c of the inner cylinder shaft 2a and the lower flange 3c. The guide ring 6 has a shaft core 7a.
A plurality of rolls 7 supported by the support shaft 6b are provided on the outer peripheral side along the circumferential direction. The roll 7 is provided with an elastic body 7b made of polyethylene or polyurethane foamed or silicone rubber on the outer periphery of a shaft core 7a. It may be formed of resin. As shown in the figure, the guide member 5 rotates the rotary shaft ART so that a predetermined clearance is formed between the guide member 5 and the lower surface of the upper flange 2b in the annular space S.
Set the length in the direction.

The rotary connector 1 constructed as described above
Adjusts the flat cable 4 to a neutral position in which the flat cable 4 is tightly wound and loosened, and accommodates the flat cable 4 in an annular space S formed by the rotating case 2 and the fixed case 3, and rewinds the flat cable 4 in a U-shape in the middle. The guide member 5 is disposed between the flat cable 4 that has been wound back, and the flat cable 4 is assembled.

Therefore, in the rotary connector 1, for example, when the rotary case 2 rotates in the direction of arrow R, one end (inner end) of the flat cable 4 is unwound from the inner cylindrical shaft portion 2a. In parallel with this, the guide member 5 smoothly moves between the flat cables 4 in the annular space S in the counterclockwise direction, and the other end (outer end) of the flat cable 4 is guided and fixed by the guide member 5. It is wound around the outer cylindrical portion 3a of the case 3.

As described above, the flat cable 4 unwound from the inner cylindrical shaft portion 2a is guided by the guide member 5 and smoothly wound around the outer cylindrical portion 3a of the fixed case 3, so that the flat cable 4 is unwound. Flat cable 4 is annular space S
There is no damage such as being folded inside. on the other hand,
When the rotating case 2 rotates in the direction of arrow L, one end (inner end) of the flat cable 4 is wound around the inner cylinder shaft 2a. In parallel with this, the guide member 5 smoothly moves clockwise between the flat cables 4 in the annular space S, and the other end (outer end) side of the flat cable 4 is guided by the guide member 5 to fix the fixed case. Since the flat cable 4 is unwound from the outer cylindrical portion 3a, no damage such as the folded flat cable 4 being folded in the annular space S is received.

In this manner, the rotary connector 1 can smoothly rotate the rotary case 2 relative to the fixed case 3 within a range corresponding to the length of the flat cable 4. At this time, the rotary connector 1 is configured such that the flange 6a of the guide ring 6 constituting the guide member 5 is formed by the step 2c of the inner cylindrical shaft 2a.
And the lower flange 3c. For this reason,
The guide member 5 does not move in the direction of the rotation axis ART even when the rotary connector 1 is mounted on a steering device of an automobile and vibrates. Therefore, in the rotary connector 1, the guide member 5 does not collide with the inner surface of the upper flange 2b of the rotary case 2 and does not generate an unpleasant collision sound.

[0015]

According to the first aspect of the present invention, it is possible to provide a rotary connector which can prevent the vibration of the guide member for reversing the belt-shaped transmission line into a U-shape and operate quietly. Can be provided at a low cost because it has a simple shape only by providing

[Brief description of the drawings]

FIG. 1 is a sectional front view of a rotary connector according to the present invention.

FIG. 2 is a cross-sectional view of the rotary connector of FIG. 1 cut along a plane perpendicular to a rotation axis and viewed from below.

[Explanation of symbols]

 Reference Signs List 1 rotating connector 2 rotating case (first case) 3 fixed case (second case) 4 flat cable 5 guide member 6 guide ring 6a flange 6b support shaft 7 roll 7a shaft core 7b elastic body ART rotation shaft S annular space

Claims (1)

[Claims] A first case and a second case, which are combined with each other so as to be rotatable relative to each other and have an annular space formed therein, one end of which is provided in the first case, and the other end of which is provided in the second case.
A rotary connector having a band-shaped transmission line fixed and spirally wound and housed in the annular space,
The band-shaped transmission line is wound back into a U-shape in the middle, and between the wound band-shaped transmission line, it is movable in the circumferential direction in the annular space and rotatably supports a plurality of rollers. C having a flange portion sandwiched between engagement portions of the two cases.
A rotary connector, wherein a ring-shaped guide member is arranged.