JP7129360B2 - rotating connector - Google Patents

Description

The present invention relates to rotating connectors.

2. Description of the Related Art Conventionally, rotary connectors have been used to electrically connect members that rotate relative to each other, such as a steering wheel and a steering column of an automobile. Patent document 1 discloses this type of rotary connector.

The rotary connector device of Patent Literature 1 includes a rotator having a rotating ring plate and an inner cylindrical portion, and a stator having a stationary ring plate and an outer cylindrical portion. The rotator and the stator are fitted together so as to be relatively rotatable. A gap is provided between the rotation-side ring plate of the rotator, the stator, and the outer cylindrical portion. A cable electrically connecting the rotator side and the stator side is housed in the housing space formed by the rotator and the stator.

Japanese Patent No. 5065508

In the configuration of Patent Document 1, there is a possibility that liquid such as water may enter the housing space of the rotary connector device from the external space of the rotary connector device through the gap provided between the rotator and the stator. . Since the stator is provided with a guide projecting piece or the like, once the liquid enters the accommodation space, it is difficult to be discharged. Therefore, insulation failure is likely to occur in the accommodating space, and improvement has been desired.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a rotary connector capable of reliably and quickly discharging liquid such as water that has entered the internal space.

Means and Effects for Solving Problems

The problems to be solved by the present invention are as described above. Next, the means for solving the problems and the effects thereof will be described.

According to the aspect of the present invention, a rotary connector having the following configuration is provided. That is, this rotary connector includes a first case, a second case, and a cable. The second case is positioned inside the first case and is attached to the first case so as to be relatively rotatable so that an annular accommodation space is formed between the second case and the first case. The cable is housed in the housing space. The cable electrically connects a first connector provided on the first case and a second connector provided on the second case. A gap is formed between the first case and the second case to connect the outer space of the cable housing composed of the first case and the second case and the housing space. In the first case, a groove extending in the circumferential direction is formed radially outward of the accommodation space. The groove portion is connected to the gap and the accommodation space, respectively. In the first case, a discharge hole is formed in a radially outer wall portion of the groove portion. The discharge hole connects the groove and the external space of the cable housing.

As a result, by installing the rotary connector so that the discharge hole is located at the bottom, even if liquid such as water enters the inside of the rotary connector through the gap between the first case and the second case, the liquid can be reliably and quickly discharged using the discharge hole after being preferentially guided to the groove. Therefore, insulation failure in the rotary connector can be prevented.

In the rotary connector described above, it is preferable that the groove is formed continuously over a half circumference or more from a position where it is connected to the discharge hole.

As a result, even if liquid enters from various places in the gap in the circumferential direction, it can be discharged from the discharge hole through the groove.

In the rotary connector described above, it is preferable that a plurality of discharge holes are formed.

Thereby, the liquid can be discharged smoothly.

In the rotary connector described above, it is preferable that the discharge hole is formed in a slit shape.

As a result, it is possible to prevent foreign matter from entering the internal space of the rotary connector through the discharge hole.

1 is a side view showing the overall configuration of a steering roll connector according to one embodiment of the present invention; FIG. FIG. 1 is a cross-sectional view taken along line AA of FIG. FIG. 3 is a partially enlarged view of FIG. 2; Partial sectional view of a stator.

Next, embodiments of the invention will be described. FIG. 1 is a side view showing the overall structure of a steering roll connector 1 according to one embodiment of the invention. 2 is a cross-sectional view taken along line AA of FIG. 1. FIG. 3 is a partially enlarged view of FIG. 2. FIG. FIG. 4 is a partial cross-sectional view of the stator 11. FIG.

A steering roll connector 1 as a rotating connector shown in FIG. 1 is provided, for example, at an appropriate position on a steering column of a vehicle body. The steering roll connector 1 is installed between a steering lower cover 3 and a column cover 5 provided on the steering column cover, as shown in FIG. The steering roll connector 1 is mainly located inside the column cover 5 .

The steering roll connector 1 has a cable housing 13 . The cable housing 13 includes a stator (first case) 11 and a rotator (second case) 12 . The stator 11 and the rotator 12 are rotatable relative to each other. The stator 11 is fixed to an appropriate member on the vehicle body side, for example, a combination bracket switch (not shown) of the steering column.

Cable housing 13 is formed in a circular shape. An insertion hole 19 is formed in the central portion of the cable housing 13 . The insertion hole 19 is provided so as to pass through the cable housing 13 in its axial direction. A steering shaft (not shown) supported by a steering column is inserted into the insertion hole 19 . The entire housing of the steering roll connector 1 may be configured as the cable housing 13 , or a portion of the housing may be configured as the cable housing 13 .

The stator 11 is attached rotatably relative to the steering shaft. The rotator 12 is configured to rotate together with the steering shaft. A steering wheel is fixed to the steering shaft.

As shown in FIGS. 2 and 3 , the rotator 12 is attached to the stator 11 so as to be relatively rotatable while positioned inside the stator 11 . The rotator 12 can rotate with respect to the stator 11 about the same axis as the rotation axis of the steering shaft.

The stator 11 includes an annular fixed-side ring plate 21 and a cylindrical outer cylindrical portion (outer peripheral portion) 31 provided on the outer peripheral edge portion of the fixed-side ring plate 21 . The rotator 12 includes an annular rotation-side ring plate 22 and a cylindrical inner peripheral cylinder portion 32 provided on the inner peripheral edge portion of the rotation-side ring plate 22 .

In this embodiment, the stationary-side ring plate 21 and the rotating-side ring plate 22 each have an annular shape. The outer cylindrical portion 31 and the inner cylindrical portion 32 each have a cylindrical shape. The stationary ring plate 21 , the rotating ring plate 22 , the outer cylindrical portion 31 and the inner cylindrical portion 32 are arranged so that their axial directions are the same as the axial direction of the cable housing 13 . Hereinafter, these axial directions may be simply referred to as axial directions. A direction perpendicular to the axial direction is sometimes called a radial direction.

A first connector 41 is attached to the stator 11 as shown in FIG. A second connector 42 is attached to the rotator 12 . The second connector 42 rotates together with the rotation of the rotator 12 . To the first connector 41 and the second connector 42, cables (not shown) drawn out from an external electric circuit (for example, horn switch, airbag module, power supply, etc.) can be connected.

The first connector 41 is provided on the stationary ring plate 21 . The second connector 42 is provided on the rotation-side ring plate 22 . The first connector 41 and the second connector 42 are electrically connected to each other by a flexible flat cable (cable) 14 arranged inside the cable housing 13 (inside an accommodation space 15 described later).

The fixed-side ring plate 21 is arranged so that its thickness direction faces the axial direction. The rotation-side ring plate 22 is arranged so that its thickness direction faces the same direction as the fixed-side ring plate 21 . The rotation-side ring plate 22 has an outer diameter slightly smaller than the outer diameter of the fixed-side ring plate 21 in this embodiment. The rotating-side ring plate 22 and the fixed-side ring plate 21 are arranged at positions separated by a predetermined distance so as to face each other in the axial direction.

The outer cylindrical portion 31 extends in one axial direction from the outer peripheral edge portion of the stationary-side ring plate 21 . The inner peripheral cylindrical portion 32 extends in the other axial direction from the inner peripheral edge portion of the rotation-side ring plate 22 . The inner cylindrical portion 32 has an outer diameter smaller than the inner diameter of the outer cylindrical portion 31 . The outer cylindrical portion 31 is positioned radially outward of the inner cylindrical portion 32 . The outer cylindrical portion 31 and the inner cylindrical portion 32 are arranged at positions separated by a predetermined distance so as to face each other in the radial direction.

Accordingly, in the cable housing 13 , a housing space 15 is formed between the stator 11 and the rotator 12 attached to the stator 11 . The housing space 15 is an annular space surrounded by the fixed-side ring plate 21 and the rotary-side ring plate 22 facing each other in the axial direction, and the outer cylindrical portion 31 and the inner cylindrical portion 32 facing each other in the radial direction. be.

As shown in FIGS. 2 and 3, the accommodation space 15 accommodates the flexible flat cable 14 . The flexible flat cable 14 is accommodated in the accommodation space 15 in a wound state.

FIG. 3 is an enlarged view of part of the lower side of FIG. As shown in FIG. 3 , the outer cylindrical portion 31 is arranged so that one end portion 51 in the axial direction faces the outer peripheral edge portion 53 of the rotation-side ring plate 22 in the radial direction. One axial end portion 51 of the outer cylindrical portion 31 and the outer peripheral edge portion 53 of the rotation-side ring plate 22 are arranged with a predetermined distance therebetween in the radial direction. Thus, a first gap (gap) 55 is formed between them.

The first gap 55 opens in one axial direction. The first gap 55 extends in the circumferential direction of the outer cylindrical portion 31 and the rotation-side ring plate 22 . The first gap 55 is formed in an annular shape near the outer edge of the cable housing 13 . The first gap 55 connects the outer space 57 of the steering roll connector 1 (cable housing 13 ) and the housing space 15 . In this embodiment, the first gap 55 connects the external space 57 of the cable housing 13 and the accommodation space 15 to each other through a passage 59 formed between the outer cylindrical portion 31 and the rotation-side ring plate 22 . is doing.

A discharge hole 61 is formed in the outer cylindrical portion 31 . The discharge hole 61 opens outward of the cable housing 13 in the radial direction. That is, the discharge hole 61 is an opening separate from the first gap 55 in the cable housing 13 and opens in a direction different from the opening direction of the first gap 55 . The discharge hole 61 connects the external space 57 of the cable housing 13 and the internal space of the first groove (groove) 71 to each other.

Next, the discharge holes 61 will be described in detail. FIG. 4 is a partial cross-sectional side view of the stator 11. FIG.

As shown in FIGS. 2, 3 and 4, the outer cylindrical portion 31 has a double structure in this embodiment. The outer peripheral tubular portion 31 has a cylindrical outer peripheral tubular portion (wall portion, outer wall portion) 63 and a cylindrical inner peripheral tubular portion (inner wall portion) 65 . The inner peripheral tubular portion 65 has an outer diameter smaller than the inner diameter of the outer peripheral tubular portion 63 and is provided radially inward of the outer peripheral tubular portion 63 . The outer outer peripheral tubular portion 63 and the inner outer peripheral tubular portion 65 are arranged at positions separated by a predetermined distance so as to face each other in the radial direction, and are coaxially arranged.

A connecting portion 67 connects an axially intermediate portion of the outer peripheral tubular portion 63 and an axially intermediate portion of the inner peripheral tubular portion 65 . The connecting portion 67 partitions the space formed between the outer peripheral tubular portion 63 and the inner peripheral tubular portion 65 into two in the axial direction. Thereby, a first groove portion 71 and a second groove portion 72 are formed between the outer peripheral tubular portion 63 and the inner peripheral tubular portion 65 .

The first groove portion 71 is arranged on one side of the connecting portion 67 in the axial direction. The second groove portion 72 is arranged on the other axial side of the connecting portion 67 . The first groove portion 71 opens in one axial direction so that the opening portion thereof faces the first gap 55 . The first groove portion 71 extends along the outer peripheral tubular portion 63 and the inner peripheral tubular portion 65 . The first groove portion 71 has a circumferential length that is at least about half the circumferential length of the outer cylindrical portion 31 .

The first groove portion 71 functions as a dust trap that retains foreign matter such as sand that has entered the interior of the steering roll connector 1 . The first groove portion 71 is connected to the external space 57 of the cable housing 13 via the first gap 55 . The first groove portion 71 is also connected to the accommodation space 15 via the passageway 59 .

The discharge hole 61 is formed in the outer peripheral cylindrical portion 63 . The discharge hole 61 radially penetrates the outer peripheral tubular portion 63 in the radial direction. Thereby, the discharge hole 61 connects the internal space of the first groove portion 71 that extends continuously in the circumferential direction of the outer cylindrical portion 31 to the external space 57 of the cable housing 13 .

The discharge hole 61 is arranged axially on one side (first groove portion 71 side) of the connecting portion with the connecting portion 67 in the outer peripheral cylindrical portion 63 . The discharge hole 61 is arranged so as to connect to the deepest portion (bottom portion 87 portion) of the first groove portion 71 . Further, the discharge hole 61 is arranged so as to be positioned near the lowest portion of the first groove portion 71 in the circumferential direction of the outer cylindrical portion 31 when the steering roll connector 1 is installed.

The stator 11 is not particularly formed with a partition wall that partitions the first groove portion 71 in the circumferential direction. Therefore, the inside of the first groove portion 71 is long and continuous in an arc shape between the lowermost portion where the discharge hole 61 is arranged and the portion (the uppermost portion) whose phase is different from the lowermost portion by 180°. It has become a space.

Thus, the discharge hole 61 faces the inner space 75 of the column cover 5 in the outer space 57 of the cable housing 13 as shown in FIG. 2 when the steering roll connector 1 is installed. At this time, one axial end portion 77 of the discharge hole 61 is arranged at a position facing the inner space 75 of the column cover 5 or the lower end portion 79 of the column cover 5 in the axial direction. Moreover, in this embodiment, the discharge hole 61 has a slit shape.

FIG. 2 shows how the steering roll connector 1 is provided at a predetermined position on the steering column. In this state, let us consider a case where liquid such as water enters the interior through the upper gap (second gap 82 ) of the gaps formed between the steering lower cover 3 and the column cover 5 . This liquid splashes near the upper portion of the outer circumference of the steering roll connector 1 . Some of this liquid may enter the internal space of the steering roll connector 1 (cable housing 13) through the first gap 55.

However, the open end of the first groove portion 71 formed along the annular first gap 55 is positioned near the annular first gap 55 . Therefore, in the range where the first groove portion 71 is formed (at least half the circumference or more), even if the liquid enters the first gap 55 from any position, in most cases the liquid enters the first groove portion 71, It flows along the first groove portion 71 to the lowest end. FIG. 4 shows how the liquid that has entered the uppermost end of the first gap 55 flows along the first groove portion 71 to the lowermost end.

At the lowermost end of first groove 71 , discharge hole 61 is located near bottom 87 of first groove 71 . Therefore, the liquid that has reached the lowermost end of the first groove portion 71 is discharged through the discharge hole 61 without remaining at the lowermost end. Since the liquid does not accumulate in the lower portion of the first groove portion 71 , the liquid level does not rise in the lower portion of the first groove portion 71 and the liquid does not overflow into the accommodation space 15 . Therefore, liquid such as water does not splash on the primary mold of the core wire welded portion of the flexible flat cable 14 arranged in the accommodation space 15, so insulation failure can be prevented.

As described above, the steering roll connector 1 of this embodiment includes the stator 11, the rotator 12, and the flexible flat cable 14. The rotator 12 is positioned inside the stator 11 and rotatably attached to the stator 11 so that an annular accommodation space 15 is formed between the rotator 12 and the stator 11 . The flexible flat cable 14 is housed in the housing space 15 . The flexible flat cable 14 electrically connects the first connector 41 provided on the stator 11 and the second connector 42 provided on the rotator 12 . A first gap 55 is formed between the stator 11 and the rotator 12 to connect the housing space 15 to the outer space 57 of the cable housing 13 composed of the stator 11 and the rotator 12 . In the stator 11 , a first groove portion 71 extending in the circumferential direction is formed radially outside the accommodation space 15 . The first groove portion 71 is connected to the first gap 55 and the accommodation space 15 respectively. In the stator 11 , a discharge hole 61 is formed in the outer peripheral cylindrical portion 63 on the radially outer side of the first groove portion 71 . The discharge hole 61 connects the first groove portion 71 and the external space 57 of the cable housing 13 .

By installing the steering roll connector 1 so that the discharge hole 61 is positioned at the bottom, even if liquid such as water enters the inside from the first gap 55 between the stator 11 and the rotator 12, the After preferentially guiding the liquid to the first groove portion 71 , the liquid can be reliably and quickly discharged using the discharge hole 61 . Therefore, insulation failure in the steering roll connector 1 can be prevented.

In addition, in the steering roll connector 1 of the present embodiment, the first groove portion 71 is formed continuously over a half circumference or more from the position where it is connected to the discharge hole 61 .

As a result, even if liquid enters the first gap 55 from various locations (for example, near the top of the steering roll connector 1) in the circumferential direction, the liquid flows through the first groove 71 to the discharge hole 61 near the bottom of the steering roll connector 1. can be discharged from

It should be noted that not only one discharge hole 61 but also a plurality of discharge holes 61 can be formed.

When a plurality of discharge holes 61 are formed, the liquid can be discharged smoothly.

Moreover, in the steering roll connector 1 of this embodiment, the discharge hole 61 is formed in a slit shape.

This prevents foreign matter from entering the inside of the steering roll connector 1 through the discharge hole 61 .

Although the preferred embodiments of the present invention have been described above, the above configuration can be modified, for example, as follows.

In the above-described embodiment, the discharge hole 61 is formed in a slit shape, but the shape of the discharge hole 61 is arbitrary, and may be circular, square, or the like.

The discharge hole 61 may be formed in a notch shape that opens the end of the outer peripheral cylindrical portion 63 on the side closer to the opening of the first groove portion 71 (the notch for discharge is also included in the discharge hole).

The direction in which the discharge hole 61 is formed through the outer peripheral cylindrical portion 63 may be the radial direction as in the above-described embodiment, or may be inclined from the radial direction.

When a plurality of discharge holes 61 are formed, they may be formed intensively in the vicinity of the lowest portion, or may be formed in a wide range in the circumferential direction.

Although the first groove portion 71 is preferably formed continuously over half the circumference or more as described above, it may be formed less than half the circumference.

Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as described herein.

1 Steering roll connector (rotating connector)
11 stator (first case)
12 rotator (second case)
13 Cable housing 14 Flexible flat cable (cable)
15 accommodation space 31 outer cylindrical portion (peripheral portion)
41 First connector 42 Second connector 55 First gap (gap)
57 External space 61 Discharge hole 63 Outer peripheral cylindrical portion (wall portion)
71 first groove (groove)

Claims (4)

a first case;
a second case positioned inside the first case and rotatably attached to the first case such that an annular housing space is formed between the second case and the first case;
a cable that is housed in the housing space and electrically connects a first connector provided on the first case and a second connector provided on the second case;
with
A gap is formed between the first case and the second case to connect an external space of the cable housing composed of the first case and the second case and the housing space, and
In the first case, a groove portion extending in a circumferential direction is formed radially outward of the accommodation space,
The groove portion is connected to the gap and the accommodation space, respectively,
In the first case, a discharge hole is formed in a radially outer wall portion of the groove portion,
The rotary connector, wherein the discharge hole connects the groove and an external space of the cable housing. The rotating connector of claim 1, comprising:
The rotary connector, wherein the groove is formed continuously over a half circumference or more from a position where the groove is connected to the discharge hole. A rotating connector according to claim 1 or 2,
A rotary connector, wherein a plurality of the discharge holes are formed. A rotary connector according to any one of claims 1 to 3,
The rotary connector, wherein the discharge hole is formed in a slit shape.

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