JPH1027664A - Rotary connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely perform snap action of a connecting member also prevent its chattering sound, in a rotary connector of a type turnably connecting a pair of housings by the connecting member. SOLUTION: In a first housing 1, a disk-shaped bottom plate 6 having a center hole 5 and an outer cylinder part 7 vertically provided in a peripheral edge of the bottom plate 6 are integrally formed. In a second housing 2, a disk-shaped roof 8 and an inner cylinder part 9 suspension provided in a central part of the roof 8 are integrally molded, an insertion hole 10 having a stepped part 10a is provided in the inner cylinder part 9. In a connection member 3, a cylindrical part 11 having a snap pawl 11a in an upper end and a flange part 12 protruded outward from a lower end of the cylindrical part 11 are integrally molded, an elastic sheet 14 is fixed to the flange part 12. In a condition that the second housing 2 is superposed in the first housing 1, the cylindrical part 11 of the connection member 3 is inserted in the insertion hole 10 from downward of the center hole 5, the elastic sheet 14 butts against the bottom plate 6 and is compressed to be deformed, thereafter, by snapping the snap pawl 11a in the stepped part 10a, both the housings 1, 2 are turnably connected by the connection member 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary connector incorporated in a steering device of an automobile and used as an electrical connection means for an airbag system, a horn circuit, and the like.

[0002]

2. Description of the Related Art A rotary connector is generally constituted by a pair of housings which are rotatably connected to each other, and a flexible cable wound in an annular storage space defined between the housings. Both ends of the flexible cable are electrically led to the outside while being fixed to both housings. One of the two housings is used as a movable body, and the other is used as a fixed body. When the movable housing is rotated in either the forward or reverse direction, the flexible cable is wound or wound in the accommodating portion according to the rotation direction. It is to be returned.

[0003] As shown in Fig. 6, a rotary connector in which a pair of housings are rotatably connected by a connecting member is conventionally known. Such a known rotary connector comprises first and second housings 1, 2 and both housings 1, 2.
A connecting member 3 for rotatably connecting the two housings 1 and 2,
And a flat cable 4 connecting the two.

The first housing 1 has a disk-shaped bottom plate 6 having a center hole 5 and an outer cylindrical portion 7 erected on the outer peripheral edge of the bottom plate 6, and these are integrally formed of synthetic resin. Have been. The second housing 2 made of synthetic resin is provided with a disc-shaped top plate 8.
And an inner cylindrical portion 9 vertically provided at the center of the top plate 8, and the inner cylindrical portion 9 is provided with an insertion hole 10 having a step portion 10a in the middle. The connecting member 3 made of synthetic resin has a cylindrical portion 11.
And a flange 12 protruding outward from the lower end of the tubular portion 11, and a snap claw 11 a is formed at the upper end of the tubular portion 11. The connecting member 3 is inserted from the center hole 5 of the bottom plate 6 into the insertion hole 10 of the inner cylindrical portion 9, the snap claw 11 a is snapped into the step portion 10 a, and the flange portion 12 is formed around the center hole 5 of the bottom plate 6. , The housings 1 and 2 are rotatably connected to each other. In this connection state, an annular storage space 13 is defined between the housings 1 and 2, and the flat cable 4 is spirally wound in the storage space 13, for example. The flat cable 4 has a plurality of conductors parallel to each other. One end of the flat cable 4 is led out of the first housing 1 while being fixed to the outer cylinder 7, and the other end is fixed to the inner cylinder 9. It is led out of the second housing 2 in a state.

[0005] In the rotary connector configured as described above,
When the second housing 2 is rotated clockwise or counterclockwise, the second housing 2 and the connecting member 3 snapped into the second housing 2 rotate with respect to the first housing 1. At that time, the second housing 2 uses two places, the lower end of the outer peripheral edge of the top plate 8 and the lower end of the inner cylindrical portion 9 as sliding surfaces, and
The connecting member 3 rotates with respect to the first housing 1 with the flange 12 as a sliding surface. Therefore, for example, the second
When the housing 2 rotates counterclockwise, the flat cable 4 is fed out of the outer tube 7 and wound around the inner tube 9, and conversely, when the second housing 2 rotates clockwise, the flat cable 4 turns inside. It is unwound from the tube portion 9 and rewound to the outer tube portion 7, and the electrical connection between the housings 1 and 2 is maintained via the flat cable 4 in any state.

[0006]

In the above-mentioned conventional rotary connector, the first and second housings 1 and 2 are rotatably connected by the connecting member 3, so that the shapes of the two housings 1 and 2 are simplified. This has the advantage that the mold cost can be reduced. However, the inner cylindrical portion 9 of the connecting member 3 is inserted into the insertion hole 10 from the center hole 5 of the bottom plate 6, and the snap claw 11a of the connecting member 3 is set to the stepped portion 10 of the second housing.
a, when the snap claw 11a is not adapted to be inserted beyond the step 10a, the snap claw 11a is snapped into the step 10a.
The flange portion 12 abuts against the bottom plate 6, and reliable snap-in cannot be performed. Therefore, although slightly longer set than the distance L ₂ of the distance L ₁ from the flange portion 12 until the snap claws 11a from the bottom plate 6 to the stepped portion 10a, after snap, the difference between the distance (L ₁ -L _Since a clearance corresponding to ₂ ) is formed between the flange portion 12 and the bottom plate 6, there is a problem that the connecting member 3 is easily rattled in the axial direction, and rattling noise is generated.

[0007]

According to the present invention, an elastic member is provided between a retaining flange of a connecting member and a housing facing the flange. When the elastic member is interposed between the flange and the housing in this way, when the snap piece of the connecting member is snap-locked to one of the housings, the elastic member is compressed and deformed between the flange and the other housing. Therefore, the snap-in operation of the connecting member can be reliably performed, and the elastic member returns elastically after the snap-in, so that the play of the connecting member is prevented.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a rotary connector according to the present invention, a pair of housings defining a storage space therein, a connecting member for rotatably connecting the two housings, and both ends wound in the storage space. And a flexible cable fixed to the two housings, wherein the connecting member has a snap piece snap-locked to one of the two housings, and a retaining flange locked to one of the other housings. Department and
An elastic member was provided between the flange and the housing.

The elastic member can be provided on the flange side of the connecting member or on the housing side facing the flange. In particular, when an elastic arm as an elastic member is integrally formed with the flange, With a simple configuration, it is possible to prevent rattling of the connecting member.

It is also possible to use an elastic sheet as the elastic member. In particular, when the elastic sheet has a multilayer structure in which a slip sheet is provided on the surface thereof, the sliding between the flange portion and the housing can be smoothly performed. can do.

Further, when the elastic sheet is attached to one of the flange and the housing, the elastic sheet slides only on one of the flange and the housing, thereby preventing uneven wear of the elastic sheet. it can. In addition, since a separate elastic sheet is used, the pressing force due to elasticity can be adjusted by selecting the thickness and material of the elastic sheet.

[0012]

Embodiments will be described with reference to the drawings.
FIG. 1 is a sectional view of a rotary connector according to one embodiment of the present invention,
FIG. 2 is an explanatory view of an elastic member provided in the rotary connector, and portions corresponding to FIG. 6 are denoted by the same reference numerals.

The rotary connector according to this embodiment is different from the conventional example shown in FIG. 6 in that an elastic sheet 14 as an elastic member is provided between the bottom plate 6 of the first housing 1 and the flange 12 of the connecting member 3. The other configuration is basically the same. That is, the rotary connector is roughly composed of the first and second housings 1 and 2, a connecting member 3 for rotatably connecting the two housings 1 and 2, and a flat cable 4 for connecting between the two housings 1 and 2. ing.

As shown in FIG. 2, the elastic sheet 14
Is an elastic body 1 made of an elastic material such as urethane rubber.
5 and a lubricating sheet 16 made of a material having excellent lubricity such as Teflon. The elastic body 15 and the lubricating sheet 16 are integrated by thermocompression bonding or the like. The elastic sheet 14 is punched in a ring shape, and is attached to the flange 12 of the connecting member 3 so that the lubricating sheet 16 faces the surface.

The assembling work of the rotary connector thus constructed will be described. First, with the both ends of the flat cable 4 fixed to the outer tube 7 and the inner tube 9, the second housing is attached to the first housing 1. The center hole 5 and the insertion hole 10 are aligned with each other. Next, the cylindrical portion 11 of the connecting member 3 is inserted into the insertion hole 10 from below the center hole 5,
By snapping the snap claw 11a into the step 10a, the housings 1 and 2 are rotatably connected by the connecting member 3. At this time, the snap claw 11a is
The elastic sheet 14 abuts against the bottom plate 6 and is compressed and deformed immediately before snap-in to the snap claw 11a.
After the snap-in, the elastic sheet 14 returns to its own elasticity and is pressed against the bottom plate 6 after snap-in.

Therefore, when the rotary connector is incorporated in a steering device of an automobile, even if vibration is applied to the rotary connector from the automobile, the connecting member 3 does not rattle in the axial direction, and rattling noise is generated. Is prevented. Further, when the second housing 2 and the connecting member 3 rotate in conjunction with the handle, the elastic sheet 14 rotates while the smooth sheet 16 on the surface slides on the bottom plate 6 of the first housing 1, thereby reducing the sliding noise. Elastic sheet 1
4 can be prevented from being unevenly worn.

FIGS. 3 to 5 show modified examples of the elastic member. In the embodiment shown in FIG. 3, a plurality of elastic arms 17 as an elastic member are formed integrally with the flange 12 of the connecting member 3. It is. Each elastic arm 17 is formed in a cantilever shape on the flange portion 12, and each free end 17 a elastically contacts the bottom plate 6 of the first housing 1, thereby preventing the connecting member 3 from rattling in the axial direction. You.

In the embodiment shown in FIG. 4, the elastic force of the elastic arm 18 is increased by forming each elastic arm 18 integrally formed on the flange 12 of the connecting member 3 into a doubly supported beam. Each elastic arm 18
Has a mountain-shaped projection 18a, and each projection 18a elastically contacts the bottom plate 6 of the first housing 1, thereby preventing the connecting member 3 from rattling in the axial direction.

In the embodiment shown in FIG. 5, a pair of elastic arms 19 project radially outward from the flange 12 of the connecting member 3. At the tip of each elastic arm 19, a protruding portion 19a is bent upward.
Are formed, and each projection 19a is
By elastically contacting the bottom plate 6, the connection member 3 is prevented from rattling in the axial direction.

[0020]

The present invention is embodied in the form described above and has the following effects.

By providing an elastic member between the retaining flange of the connecting member and the housing facing the flange,
When the snap piece of the connecting member is snap-locked to one of the housings, the elastic member is compressed and deformed between the flange portion and the other housing, so that the snap-in operation of the connecting member can be reliably performed. At the same time, since the elastic member returns elastically after snap-in, rattling noise of the connecting member can be prevented.

Further, when the elastic arm as the elastic member is integrally formed with the flange, the backlash of the connecting member can be prevented with a simple configuration.

It is also possible to use an elastic sheet as the elastic member. In particular, when the elastic sheet has a multilayer structure in which a slip sheet is provided on the surface, the sliding between the flange portion and the housing can be smoothly performed. can do.

Further, when the elastic sheet is adhered to one of the flange and the housing, the elastic sheet slides only on one of the flange and the housing, so that uneven wear of the elastic sheet can be prevented. it can. In addition, since a separate elastic sheet is used, the pressing force due to elasticity can be adjusted by selecting the thickness and material of the elastic sheet.

[Brief description of the drawings]

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

FIG. 2 is an explanatory view of an elastic member provided in the rotary connector of FIG. 1;

FIG. 3 is a perspective view of a connecting member showing a modification of the elastic member.

FIG. 4 is a perspective view of a connecting member showing a modification of the elastic member.

FIG. 5 is a perspective view of a connecting member showing a modification of the elastic member.

FIG. 6 is a sectional view of a rotary connector according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st housing 2 2nd housing 3 Connecting member 4 Flat cable (flexible cable) 5 Center hole 6 Bottom plate 7 Outer cylinder part 8 Top plate 9 Inner cylinder part 10 Insertion hole 10a Step part 11 Cylindrical part 11a Snap nail 12 Flange 13 Storage space 14 Elastic sheet 15 Elastic body 16 Smooth sheet 17, 18, 19 Elastic arm

Claims (5)

[Claims] 1. A pair of housings defining a storage space therein, a connecting member rotatably connecting the two housings, and a pair of housings wound in the storage space and both ends fixed to the two housings. A flexible cable, and the connecting member is provided with a snap piece that is snap-locked to one of the two housings, and a retaining flange that is locked to one of the other housings. A rotary connector having an elastic member interposed between the housing and a housing. 2. The rotary connector according to claim 1, wherein the elastic member is an elastic arm formed integrally with the flange. 3. The rotary connector according to claim 1, wherein the elastic member is an elastic sheet. 4. The rotary connector according to claim 3, wherein a slip sheet is provided on a surface of the elastic sheet. 5. The rotary connector according to claim 3, wherein the elastic sheet is adhered to one of the flange and the housing.