MXPA99006477A - A rotatory connector - Google Patents

Abstract

Un conector rotatorio que incluye un cuerpo movible que tiene un soporte inferior con una porción exterior de extensión la cual estáorientada hacia un extremo en dirección a lo ancho de cable flexible tiene una porción extrema conectora la cual se extiende más alláde la porción exterior de extensión y la cual esta conectada a una porción conectora lateral estacionaria provista en un primer alojamiento;por ejemplo, un corte estáformado en el cable flexible para evitar que un borde de la porción extrema conectora del cabello flexible y la porción exterior de extensión hagan contacto uno con otro en una posición de cruce;usando una estructura sencilla, el conector rotatorio el cual hace posible reducir el nivel de ruido de deslizamiento producido como resultado del deslizamiento entre el cable flexible y la porción exterior de extensión del soporte inferior del cuerpo movible.

Description

ROTATING CONNECTOR BACKGROUND OF THE INVENTION 1. FIELD OF THE INVENTION The present invention relates to a rotary connector which is incorporated in a steering system of a motor vehicle and which is used with an electrical connecting means for an airbag system or the like. 2. DESCRIPTION OF THE RELATED TECHNIQUE The rotary connectors are formed by connecting a pair of housings, which are coupled to each other in a concentric and relatively rotatable manner, by means of a flexible cable as a belt. They are generally classified into two types depending on the way in which the flexible cable is wound. In the first type, the flexible cable is wound as a swirl in an annular receiving portion defined by the pair of housings. The second type, the flexible cable is wound in the reverse direction in the receiving portion. In the second type, the required length of the flexible cable can be made shorter. Therefore, the second type has the advantage of reduced total costs. However, in conventional rotary connectors, when the flexible cable is subjected to automobile vibrations and moves vertically in the receiving portion, both ends in the width direction of the flexible cable collide with the upper frame and the lower cover of the first accommodation, resulting in the generation of unpleasant noise in the ear. To try to solve this problem, the applicant proposed a rotary connector in the European patent publication No EP0770521A1. The rotary connector comprises a first housing and a second housing coupled to each other in a concentric and relatively rotatable manner; a flexible cable as a strap which is wound in the reverse direction through the annular receiving portion defined by the housings, both ends of the flexible cable being secured to the housings; and a movable body which is rotatably disposed in the receiving portion and which has a hole through which the turning portion of the flexible cable passes. In the rotary connector, an outer extension portion is formed in the movable body in order to resist the ends in the width direction of the flexible cable. The flexible cable is held in the outer extension portion to reduce the noise level. Figure 9 is a partial plan view showing in section a portion of the lateral connector portion of the first flexible cable housing of the proposed rotary connector. Figure 10 is a sectional view taken on line 10-10 of Figure 9. As shown in Figure 9, a flexible cable 4 crosses at point P an outer extension portion 17b of a lower support 17 (see 10) of a movable body extending to a stationary lateral connector portion 31 provided in an upper frame 8 (see FIG. 10) of a first housing. An end connector portion of flexible cable 4 is connected to the stationary lateral connector portion 31. The reference number 18 symbolizes a roller of the movable body. However, in this structure, the outer portion of extension 17b of the lower support 17 makes contact with an edge of the flexible cable 4 at the point P (of figure 9), as shown in figure 10. Therefore, when the slip occurs in the portion where it contacts one with another, noise is generated.

BRIEF DESCRIPTION OF THE INVENTION Accordingly, in view of the above-described conventional problem, it is an object of the present invention to provide a rotary connector with a simple structure which avoids the production of noise resulting from the sliding between the flexible cable and the outer extension portion of the lower support of the movable body For this purpose, according to the present invention, there is provided a rotary connector comprising: a first housing and a second housing, which are coupled to each other in a concentric and relatively rotatable manner; a flexible cable as a belt that is wound in the reverse direction through a turning portion in an annular receiving portion defined by the first housing and the second housing, both ends of the flexible cable being fixed to the first housing and the second housing; and a movable body which is rotatably disposed in the receiving portion, the movable body having an opening through which the turning portion of the flexible cable passes; wherein the movable body has an outer extension portion which is oriented toward one end in the width direction of the flexible cable; wherein the connector end portion of the flexible cable crosses the outer extension portion of the movable body in order to be connected to a stationary lateral connector portion of the first housing; and wherein an edge of the connector end portion of the flexible cable and the outer extension portion of the movable body are arranged to make contact with each other in the position crossing the edge of the connector end portion of the flexible cable and the outer portion of extension of the movable body. In a preferred embodiment, the edge of the connector end portion of the flexible cable may have a cutout formed therein to prevent the edge of the connector end portion of the flexible cable and the outer extension portion of the movable body from contacting each other. In another preferred embodiment, the edge of the connector end portion of the flexible cable can be lifted by a portion of the first housing to prevent the edge of the connector end portion of the flexible cable and the outer extension portion of the movable body from contacting one another with other. In still another preferred embodiment, the edge of the connector end portion of the flexible cable can be lifted by the stationary lateral connector portion of the first housing to prevent the edge of the connector end portion of the flexible cable and the outer extension portion of the movable body make contact with each other. In still another preferred embodiment, one end of the outer extension portion may extend upwardly. In still another preferred embodiment, when one end of the outer extension portion extends upward, the edge of the connector end portion of the flexible cable may have a cutout formed therein to prevent the edge of the cable connector end portion from flexible and the outer extension portion of the movable body make contact with each other. In still another preferred embodiment, when one end of the outer extension portion extends upwardly, the end of the connector end portion of the flexible cable can be lifted by a portion of the first housing to prevent the edge of the connector end portion of the flexible cable. flexible cable and the outer extension portion of the movable body make contact with each other. In still another preferred embodiment, when one end of the outer extension portion extends upwards, the edge of the connector end portion of the flexible cable can be lifted by the stationary lateral connector portion of the first housing to prevent the edge of the portion The extreme connector of the flexible cable and the other outer extension portion of the movable body make contact with each other.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a sectional view of a first embodiment of the rotary connector according to the present invention. Figure 2 is an exploded perspective view of the rotary connector of Figure 1. Figure 3 is a semi-sectional view of a second embodiment of the rotary connector in accordance with the present invention. Figure 4 is a semi-sectional view of a third embodiment of the rotary connector according to the present invention. Figure 5 is a semi-sectional view of a fourth rotary connector embodiment according to the present invention. Figure 6 illustrates the relationship between the flexible cable and the outer extension portion, in a first specific example. Figure 7 shows a structure for preventing the flexible cable and the outer extension portion from contacting each other, in a second specific example.

Figure 8 shows another structure to prevent the flexible cable and the outer extension portion from contacting each other, in a third specific example. Figure 9 is a partial plan view showing sectionally a portion of the side connector portion of the first housing of the flexible cable in the rotary connector proposed by the applicant. The view 10 is a sectional view on line 10-10 of the figure 9. DESCRIPTION OF THE PREFERRED MODALITIES In accordance with the present invention, the mobile connector is constructed so as to eliminate the problem that an edge of a connector end portion of a flexible cable and an outer extension portion of a movable body make contact with each other in the portion in where they cross. This is achieved by forming a cut in an edge of the connector end portion of the flexible cable or by lifting an edge of the connector end portion of the flexible cable through a portion of the first housing, or by lifting an edge in the flexible cable connector end portion by a stationary lateral connector portion of the first housing. Therefore, a simple structure can be used to completely solve the problem of noise generation that results from sliding between an edge of the connector end portion of the flexible cable and the outer extension portion of the movable body.

A description will now be given of the preferred embodiments of the rotary connector of the present invention, with reference to the drawings. The figure 1 is a sectional view of a first embodiment of the rotary connector. The figure 2 is an exploded perspective view of the rotary connector of Figure 1. As shown in these figures, the rotary connector generally comprises a first housing 1; a second housing 2 rotatably connected to the first housing 1; a flexible cable 4 wound on an annular receiving portion 3 defined by the housings attached; and a movable body 5 rotatably disposed in a receiving portion 3. The first housing 1 comprises the upper beater 8 having an outer tubular portion 7 extending vertically downward from the outer peripheral edge of an upper iron 6; and a lower cover 9 which is integrally joined to the lower end of the outer tubular portion 7. A curved portion 8a in the form of r is formed in a portion in which the upper plate 6 and the outer portion of the tube 7 are bonded together. in an inner wall of the upper frame 8. The central holes 10 and 11 are formed in the central portions of the upper plate 6 of the upper frame 8 and the lower cover 9, respectively. An annular guide cavity 12 is formed in the lower surface of the lower cover 9. The second housing 2 is a tubular body having an axis insertion hole 13 in the central portion thereof. The outer peripheral surface thereof is an inner tubular portion 14.

An annular sliding layer 15 is interposed immediately between the upper outer peripheral edge of the second housing 2 and the central hole 10 of the upper frame 8. The housings 1 and 2 are rotatably coupled to each other by the sliding lid 15 which acts as a sliding portion. . The sliding lid 15 is molded with a type of synthetic resin that is different from the type of synthetic resin used to form the housings 1 and 2. A thin flange portion 15a is formed on the lower outer peripheral surface of the sliding layer 15. receiving portion 3 is defined by the upper plate 6, the outer tubular portion 7 and the lower cover 9, of the first housing 1, and the inner tubular portion 14 of the second housing 2. In the receiving portion 3, a gap G is formed between the flange 15a of the sliding layer 15 and the upper plate 6 The flexible cable 4 is a flat cable, like a belt, which is formed by laminating parallel conductors with a pair of insulating films. Both ends of the flexible cable 4 are secured to the outer tubular portion 7 and the inner tubular portion 14, respectively, and are then removed from the first housing 1 and the second housing 2, respectively. In the receiving portion 3, the flexible cable 4 is wound clockwise along the inner wall of the outer tubular portion 7. Then, the portion of the flexible cable 4 wound in the direction of the hands of the The watch is rolled in a U-shape to reverse its winding direction, forming a turning portion 4a. After that, the flexible cable 4 is wound in the counterclockwise direction around the outer wall of the inner tubular portion 14. The mobile body 5 comprises an upper annular support 16 and a lower annular support 17, which resist each other and are separated by a predetermined distance; a plurality of rollers 18 supported axially between the supports 16 and 17; and a stationary tube 19 fixed between the supports 16 and 17. A plurality of elastic arms 20 is molded integrally to the inner surface of the lower support 17. The lower support 17 has a width greater than that of the upper support 16 in the diametral direction thereof. . An inner extension portion 17a and an outer extension portion 17b, which are formed on both peripheral edges of the lower support 17, protrude beyond the rollers 18 and the stationary tube 19. The movable body 5 is disposed in the receiving portion 3 and each elastic arm 20 slides on the guide cavity 12 of the lower cover 9, whereby the movable body 5 is guided rotatably in the diametrical direction of the receiving portion 3. Here, the turning portion 4a of flexible cable 4 it passes through an opening between the stationary tube 19 and one of the rollers 18, and is wound around the roller 18. The inner winding portion of the flexible cable 4 is maintained between the flange portion 15a of the sliding cover 15 and the inner extension portion 17a of lower support 17. On the other hand, the outer winding portion of flexible cable 4 is maintained between curved portion 8a of upper frame 8 and to outer extension portion 17b of lower support 17.

A description will now be given of the operation of the rotary connector in which case the first housing 1 is used as the stationary body and the second housing 2 is used as the movable body. In this case, the housing 1 is fixed to one side of the steering column of the steering system, while the second housing 2 is coupled to a steering shaft, a steering wheel or the like. During the use of the rotary connector, when the steering wheel is rotated either clockwise or counterclockwise, the torque of the steering wheel is transmitted to the second housing 2, causing it to rotate either clockwise or counterclockwise. For example, when the second housing 2 is rotated clockwise from a corresponding position of the neutral position of the steering wheel, the turning portion 4a of the flexible cable 4 is rotated by an amount that is slightly less than the amount of rotation of the second housing 2. One of the rollers 18 is then pulled by the turning portion 4a, causing the movable body 5 to move in a clockwise direction with the movement of the turning portion. 4a. The flexible cable 4 of the outer tubular portion 7 is pulled out to a length whose value is approximately twice the value of the movement amount of the turning portion 4a and the movable body 5. Then, it is wound around the surface peripheral of the inner tubular portion 14.

In contrast to this, when the second housing is rotated 2 in the counterclockwise direction from the position corresponding to the neutral position of the steering wheel, the turning portion 4a of the flexible cable 4 moves in the counterclockwise direction in an amount that is slightly less than the amount of rotation of the second housing 2. The turning portion 4a moves away from the roller 18 and pushes the stationary tube 19, causing the movable body 5 to move counterclockwise with the movement of the turning portion 4a.

The flexible cable 4 of the inner tubular portion 14 is pulled out to a length whose value is approximately twice the value of the movement amount of the turning portion 4a and of the movable body 5. Then, it is wound up again around the the outer tubular portion 7. During operation, the sliding lid 15 is immediately interposed between the relative sliding positions of the housings 1 and 2, making it possible to greatly reduce the noise level resulting from the sliding when the second housing 2 is rotated. a vertical force (i.e., a force in the axial direction of the steering wheel) acts on the flexible cable 4 due to the vibrations transmitted by the automobile, the flexible cable 4 tries to move vertically in the receiving portion 3. However, in the rotary connector, the ends in the width direction of the inner winding portion of the flexible cable 4 are oriented towards the flange portion 15a of the sliding lid 15 and the outer extension portion 17a of the outer support 17. Therefore, when both ends in the width direction of the flexible cable 4 collide with the flange portion 15a and the inner portion of the extension 17a, the sliding noise is absorbed by the sliding lid 15 and the lower support 17.

Particularly in the case in which a predetermined gap G is formed between the flange portion 15a of the sliding lid 15 and the upper plate 6, the sliding lid 15 is extremely effective in absorbing the sliding noise, making it possible to virtually eliminate the problem of the sliding noise (caused by the flexible cable 4) escaping from the housings 1 and 2. This is because the flange portion 15a buckles in the gap G. The elastic arms 20 are provided in the lower surface of the lower support 17. Therefore, even when the flexible cable 4 collides with the lower support 17, the flexible cable is elastically latched by the lower support 17, making the sliding noise particularly insignificant. The ends in the width direction of the outer winding portion of the flexible cable 4 are oriented towards the curved portion 8 of the upper frame 8 and the outer portion of the portion 17b of the lower support 17. The direction in which the upper end of the cable flexible 4 collides with the upper frame 8 is gradually changed by the curved portion 8a. In addition, the lower end of the flexible cable 4 is prevented from colliding with the lower cover 9 by the outer extension portion 17b. In order to reduce the size of the space in which the flexible cable 4 moves vertically and elastically ignite the flexible cable 4, the outer extension portion 17b is formed in such a way that one end thereof extends upwards and is made gradually thinner. Therefore, the slip noise produced by the outer winding portion of the flexible cable 4 and prevent it from escaping out of the housings 1 and 2 can be reduced. Figure 3 is a semi-sectional view of a second embodiment of the rotary according to the present invention. In the figure, the component parts corresponding to those of figure 1 are given the same reference numbers. The second embodiment is different from the first embodiment in which the inner extension 17a of the lower support 17 is omitted.; that, in addition to the sliding lid 15, a sliding lid 21 similar to the sliding lid 15 is interposed immediately between the lower outer peripheral edge of the second housing 2 and a central hole 11 of the lower cover 9; and that a flange portion 21a of the sliding lid 21 is disposed so as to be oriented towards the lower end of the widthwise direction of the flexible cable 4. The other structural characteristics of the rotary connector of the second embodiment are basically the same as those of the second embodiment. of the rotary connector of the first mode. When the housings 1 and 2 are rotatably coupled to one another through the sliding covers 15 and 21, the second housing 2 can rotate uniformly and the sliding noise produced when the second housing 2 is rotated can be further reduced. that the flange portions 15a and 21a of their respective sliding covers 15 and 21 are oriented towards both ends in the width direction of the inner winding portion of the flexible cable 4, the flexible cable 4 is resiliently supported by the flange portions 15a and 21a. Therefore, slip noises produced when the flexible cable 4 collides with the flange portions 15a and 21a can be virtually eliminated completely. Figure 4 is a semi-sectional view of a third embodiment of the rotary connector according to the present invention. In this figure, the corresponding parts to those of Figure 1 are given the same reference numbers. The third embodiment differs from the first embodiment in that the sliding lid 15 is omitted, that an inner extension portion 16a of the upper support 16 is formed so as to project more inwardly than the rollers 18 and the stationary tube 19; and that other ends in the width direction of the flexible cable 4 are held between the inner extension portion 16a and the inner extension portion 17a of the lower support 17. The other structural characteristics are basically the same. In this case, the inner extension portions 16a and 17a of the supports 16 and 17 are oriented towards both ends in the widthwise direction of the outer winding portion of the flexible cable 4, so that the flexible cable 4 does not directly collide with the cable. the upper plate 6 of the upper frame 8 and the lower cover 9, making it possible to reduce the sliding noise. Figure 5 is a semi-sectional view of a fourth embodiment of the rotary connector according to the present invention. In the figure, the corresponding parts to those of figure 1 are given the same reference numbers. The fourth embodiment differs from the first embodiment in that the upper plate defining a receiving portion 3 is fopted by a flange portion 23 integrally molded to the upper end of the second housing 2 and that a sliding lid 24 or a flange portion 24a is interposed between the outer peripheral edge of the flange portion 23 and the upper end of the outer tubular portion 7. The other structural features are basically the same. The rotational sliding portions of the housings 1 and 2 can be modified, when necessary. In the fourth embodiment, the flange portion 24a of the sliding lid 24 and the outer extension portion 17b of the lower support 17 are oriented towards both ends in the widthwise direction of the outer winding portion of the flexible cable 4. Therefore still when, for any circumstance, the ends in the width direction of the flexible cable 4 collide with the flange portion 24a and the outer extension portion 17b, the sliding noise produced by the collision is absorbed by the sliding cover 15. and the lower support 17, making it possible to reduce the level of sliding noise. In the embodiments, the first housing 1 acted as the stationary body and the second housing 2 acted as the movable body. Nevertheless, the first housing 1 can act as the movable body and the second housing 2 can act as the stationary body. Although in the embodiments the noise reduction means, such as the flange portion 15a of the sliding lid 15, the flange portion 21a of the sliding lid 21 and the flange portion 24a of the sliding lid 24, as well as the portion of extension 16a of support 16 and extension portions 17a and 17b of the support 17, are disposed at the upper and lower ends of the inner winding portion and the outer winding portion of the flexible wire 4, these noise reduction means can be employed in suitable combinations. For example, instead of using the sliding lid 15 and the inner extension portion 16a of the upper support 16, an air gap can be provided inside the upper plate 6 of the upper frame 8. In this case, the noise can be reduced of sliding produced when the upper end of flexible cable 4 collides with the upper plate 6. Alternatively, one or a plurality of noise reduction means may be used. Specific examples of structures will be given to prevent the outer extension portion 17b of the lower support 17 and an edge of the connector end portion of the flexible cable 4 from contacting one another (in the position P of figure 9). Figure 6 illustrates a relationship between the flexible cable and the outer extension portion, in a specific example. In this example illustrated in Figure 6, a cut 40 is formed on one edge of the connector end portion of the flexible cable 4. The cut 40 prevents the flexible cable 4 and the other outer extension portion 17b of the lower support 17 from contacting one another. with another, thereby preventing slip noise, produced as a result of sliding between the flexible cable 4 and the outer extension portion 17b of the lower support 17.

Figure 7 illustrates a structure to prevent the flexible cable and the outer extension portion from contacting each other in a second specific example. In this specific example shown in Figure 7, one end of the connector end portion of the flexible cable 4 is lifted by a portion of the first housing 1 or, more specifically, by a vertical portion 41 that is erect at the outer periphery of the cover lower 9. The vertical portion 41 prevents the flexible cable 4 and the outer extension portion 17b of the lower support 17 from contacting each other, thereby preventing the slip noise generated as a result of sliding between the flexible cable. 4 and the outer extension portion 17b of the lower support 17. Figure 8 illustrates another structure to prevent the flexible cable and the outer extension portion from contacting each other, in a third specific example. In this example shown in Figure 8, an edge of the connector end portion of the flexible cable 4 is lifted by the stationary connector portion 31 in the upper frame 8 of the first housing 1. The stationary connector portion 31 is received in the receiving space 42 of the connector portion in the upper frame 8 and a spacer 43 is disposed below the stationary connector portion 31. The spacer 43 causes the edge of the connector end portion of the flexible cable 4 to be lifted upwards so that the flexible cable 4 and the outer extension portion 17b of the lower support 17 does not contact one another. Therefore, the level of slip noise, produced as a result of sliding between the flexible cable 4 and the outer extension portion 17b, can be reduced. In accordance with the present invention, the mobile connector is constructed so as to eliminate the problem that an edge of a connector end portion of a flexible cable and an outer extension portion of a movable body make contact with each other in the portion where they cross. This is achieved by forming a cut in an edge of the connector end portion of the flexible cable or by lifting an edge of the connector end portion of the flexible cable through a portion of the first housing, or by lifting an edge of the connector end portion of the flexible cable through a stationary lateral connector portion of the first housing. Therefore, a simple structure can be used to completely solve the problem of noise generation that results from sliding between an edge of the connector end portion of the flexible cable and the outer extension portion of the movable body.

Claims (8)

NOVELTY OF THE INVENTION CLAIMS

1. - A rotary connector comprising: a first housing and a second housing, which are coupled concentrically and relatively rotatable to each other; a flexible cable such as a belt which is wound in the reverse direction through a turning portion in an annular receiving portion defined by the first housing and the second housing, both ends of the flexible cable being fixed to the first housing and the second housing; and a movable body which is rotatably disposed in the receiving portion, the movable body having an opening through which the turning portion of the flexible cable passes; wherein a connector end portion of the flexible cable crosses the outer extension portion of the movable body in order to be connected to a stationary lateral connector portion provided in the first housing; and wherein an edge of the connector end portion of the flexible cable and the outer extension portion of the movable body are arranged so that they do not contact each other in the crossing position at the edge of the connector end portion of the flexible cable and the outer extension portion of the movable body.

2. A rotary connector according to claim 1, further characterized in that the edge of the connector end portion of the flexible cable has a cut formed therein to prevent the edge of the connector end portion of the flexible cable and the outer portion of extension of the movable body make contact with each other.

3. A rotary connector according to claim 1, further characterized in that the edge of the connector end portion of the flexible cable is lifted by a portion of the first housing to prevent the edge of the connector end portion of the flexible cable and the portion outer extension of the movable body make contact with each other.

4. A rotary connector according to claim 1, further characterized in that the edge of the connector end portion of the flexible cable is lifted by the stationary lateral connector portion provided in the first housing to prevent the edge of the connector end portion of the connector. flexible cable and the outer extension portion of the movable body make contact with each other.

5. A rotary connector according to claim 1, further characterized in that one end of the outer extension portion extends upwards.

6. A rotary connector according to claim 5, further characterized in that the edge of the connector end portion of the flexible cable has a cut formed therein to prevent the edge of the connector end portion of the flexible cable and the outer portion of extension of the movable body make contact with each other.

7. A rotary connector according to claim 5, further characterized in that the edge of the connector end portion of the flexible cable is lifted by a portion of the first housing to prevent the edge of the connector end portion of the flexible cable and the portion outer extension of the movable body make contact with each other.

8. A rotary connector according to claim 5, further characterized in that the edge of the connector end portion of the flexible cable is lifted by the stationary lateral connector portion provided in the first housing to prevent the edge of the connector end portion of the flexible cable and the outer extension portion of the movable body make contact with each other.