JP2011018618A - Rotary connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary connector with cost reduction eased.SOLUTION: A holder 6 arranged in an annular space between an outer tubular portion 7 and an inner tubular portion 9b, includes a small-diameter annular base part 6a and cylindrical bodies 6b erected at a plurality of sites, and a roller 11 is attached to the holder 6 in free rotation. An inversion part of a flat cable passes through openings 61, 62 of the holder 6, and the holder 6 is rotated and driven by the inversion part 4a which passes through the opening 61 having a small opening width in a peripheral direction. Further, flexure of the flat cable in a first gap C1 is regulated by an outer wall part 6b1 of the cylindrical body 6b, flexure of a flat cable in a second gap C2 wound around an outer peripheral surface of the inner tube part 9b is regulated by an inner wall part 6b2 of the cylindrical body 6b, and a lower end part of the flat cable in the first gap C1 and a lower end part of the flat cable on the annular base part 6a in the second gap C2 are supported at the nearly same height by a support part 7b of the outer tubular portion 7.

Description

  The present invention relates to a rotary connector that is incorporated in an automobile steering device and used as an electrical connection means for an air bag system or the like.

  This type of rotary connector rotatably connects a stator member having an outer cylinder part and a rotor member having an inner cylinder part, and in an annular space defined between the outer cylinder part and the inner cylinder part. The flat cable is housed and wound, and is used as an electrical connection means such as an air bag and an inflator attached to a handle having a limited number of rotations. The stator member is fixed to the steering column side, and the rotor member is fixed to the handle side. In addition, a flat cable is a band-shaped body in which a conductor is supported on an insulating film, and a spiral type in which the flat cable is wound in a spiral shape and a reverse type in which the flat cable is reversed in the middle and wound in the opposite direction are known. The latter inversion type is more mainstream because the length of the flat cable can be remarkably shortened.

  In such a reversing type rotary connector, the reversing portion of the flat cable is passed through the opening of a holder (moving body) that is rotatably arranged in the annular space, and the position is regulated by the holder in the annular space. One or a plurality of flat cables are housed and wound around. When the rotor member is rotated by being driven by the handle that has been rotated, the reversing portion of the flat cable moves in the same direction by a smaller amount of rotation than the rotor member, and the holder also moves in the same direction following this reversing portion. It is supposed to be. In addition, a plurality of rollers are usually rotatably attached to the holder, and the flat cable reverses the winding direction so as to be wound around a predetermined roller (see, for example, Patent Document 1).

Japanese Patent No. 3234858

  However, in the conventional rotary connector described above, a plurality of rollers are attached to a holder that is arranged in the annular space and restricts the position of the flat cable. As a result, there was a problem that the cost of the holder was inevitably increased.

  The present invention has been made in view of such a state of the art, and an object of the present invention is to provide a rotary connector that can be easily reduced in cost.

  In order to achieve the above object, the present invention provides a stator member having an outer cylinder part and a bottom plate part, and an inner cylinder part facing the outer cylinder part, and a rotor rotatably supported by the stator member. The member is housed in an annular space defined between the outer cylinder part and the inner cylinder part with the winding direction reversed halfway, and both ends thereof are fixed to the stator member and the rotor member, respectively. The rotary connector includes a flat cable and a holder that is rotatably disposed in the annular space and has an opening through which a reversing portion of the flat cable passes.The holder is extrapolated to the inner cylinder portion. An annular base portion placed on the bottom plate portion, a plurality of outer wall portions standing on the annular base portion and facing the inner peripheral surface of the outer cylinder portion with a first gap, and the annular base portion And the outer peripheral surface of the inner cylinder part A plurality of inner wall portions facing each other with a gap of 2 and a roller rotatably attached to the inside of the reversing portion, and the inner cylinder portion is rotatably engaged with an inner edge portion of the annular base portion. The outer cylinder part has a support part, and the support part is on the annular base part in the second gap and the lower end part of the flat cable in the first gap. The lower end of the flat cable is supported at substantially the same height.

  The rotary connector configured as described above can regulate the deflection of the flat cable arranged in the first gap toward the inner cylinder part side by the outer wall part of the holder, and can also regulate the flat cable arranged in the second gap. Since the deflection to the outer cylinder side can be regulated by the inner wall portion of the holder, even if there is only one roller attached to the holder, the required rotational driving force can be applied to the holder by the reversing portion of the flat cable, Cost reduction can be easily realized. Further, the holder can be easily reduced in weight because the number of rollers to be used can be greatly reduced and the outer wall portion and the inner wall portion can be dispersed and erected in the circumferential direction. Therefore, the holder can always be smoothly rotated by the reversing portion of the flat cable, and the number of parts of the entire holder including the roller can be greatly reduced, and the assemblability is improved. Moreover, the lower end portion of the flat cable is supported by the support portion of the outer tube portion of the flat cable, and the lower end portion of the inner tube portion of the flat cable is supported by the annular base portion of the holder. Is held at substantially the same height in the annular space, the rotational driving force by the inversion portion of the flat cable can be efficiently applied to the holder, and the holder can be rotated more smoothly.

  In the above configuration, the outer wall portion is formed from the first curved surface portion that protrudes radially outward of the holder, and the inner wall portion is formed from the second curved surface portion that protrudes radially inward of the holder. It is preferable that the flat cable can be smoothly slid with respect to the outer wall portion and the inner wall portion. In this case, each of the plurality of first curved surface portions and the plurality of second curved surface portions is formed by a plurality of cylindrical bodies standing in a distributed manner in the circumferential direction. It is preferable because the shape can be simplified and the mechanical strength of the outer wall portion and the inner wall portion can be easily increased.

  In the above configuration, if the holder has a plurality of elastic arm portions that protrude radially outward from the annular base portion from a plurality of locations that are substantially equidistant in the circumferential direction and that have their tips abutting against the bottom plate portion, the holder Since the contact area between the base plate and the bottom plate portion can be reduced, the holder can be rotated more smoothly.

  According to the rotary connector of the present invention, the deflection of the flat cable arranged in the first gap toward the inner cylinder part side can be regulated by the outer wall part of the holder, and the outer side of the flat cable arranged in the second gap Since the bending toward the tube side can be regulated by the inner wall portion of the holder, even if there is only one roller attached to the holder, the required rotational driving force can be applied to the holder by the reversing portion of the flat cable, Cost reduction can be easily realized. Further, the holder can be easily reduced in weight because the number of rollers to be used can be greatly reduced and the outer wall portion and the inner wall portion can be dispersed and erected in the circumferential direction. Therefore, this rotary connector can always rotate the holder smoothly by the reversing part of the flat cable, and the number of parts of the entire holder including the roller can be greatly reduced and the assemblability is improved. In addition, the lower end portion of the flat cable on the outer tube portion side is supported by the support portion of the outer tube portion, and the lower end portion of the flat cable on the inner tube portion side is supported by the annular base portion of the holder. Since a lower end part is hold | maintained at substantially the same height in annular space, the rotational drive force by the inversion part of a flat cable can be efficiently provided to a holder, and a holder can be rotated further smoothly.

It is a top view of the rotation connector concerning the example of an embodiment of the present invention. It is sectional drawing which follows the AA line of FIG. It is explanatory drawing which shows the accommodation state of the flat cable in the annular space of the rotation connector shown in FIG. It is a perspective view of the holder shown in FIG. It is a top view of the holder shown in FIG. It is a side view of the holder seen from the arrow B direction of FIG. It is a side view of the holder seen from the arrow D direction of FIG.

  FIG. 1 is a plan view of a rotary connector according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line AA of FIG. 1, and FIG. FIG. 4 is a perspective view of the holder shown in FIG. 3, FIG. 5 is a plan view of the holder, and FIG. 6 is viewed from the direction of arrow B in FIG. FIG. 7 is a side view of the holder as seen from the direction of arrow D in FIG.

  A rotary connector according to this embodiment is housed in a stator member 1, a rotor member 2 rotatably connected to the stator member 1, and an annular space 3 defined between the stator member 1 and the rotor member 2. -It is roughly comprised by the wound two flat cables 4 and 5 and the holder 6 which is arrange | positioned rotatably in the annular space 3, and lets the flat cables 4 and 5 pass. This rotary connector is incorporated in a steering device of an automobile, and electrical connection between the steering column side stator member 1 and the steering wheel side rotor member 2 is made by flat cables 4 and 5.

  The stator member 1 is a fixed side member installed on the steering column. The stator member 1 includes an outer cylinder portion 7 and a bottom plate portion 8 made of synthetic resin, and the substantially cylindrical outer cylinder portion 7 is integrated with the outer peripheral edge portion of the substantially annular bottom plate portion 8 by snap coupling. . A connector portion 7 a that protrudes outward is integrally formed on the outer cylinder portion 7, and a connector portion 8 a that is combined with the connector portion 7 a is integrally formed on the bottom plate portion 8. A fixed joint 1a is disposed inside the combination of these connector portions 7a and 8a. A support portion 7b described later is formed on the inner wall of the outer cylinder portion 7 so as to form a step with the inner surface of the bottom plate portion 8, and a center hole 8b is formed at the center of the bottom plate portion 8. . Note that the outer cylinder portion 7 and the bottom plate portion 8 of the stator member 1 can be integrally formed.

  The rotor member 2 is a movable member connected to the handle, and the rotor member 2 includes a rotor body 9 and a rotor snap 10 made of synthetic resin. The rotor body 9 includes an annular top plate portion 9a that faces the bottom plate portion 8, and an inner cylinder portion 9b that hangs down from the center of the top plate portion 9a. An inner diameter of the inner cylinder portion 9b is set to a size that allows the steering shaft to be inserted. A stepped portion that rotatably engages and holds the inner edge portion of the holder 6 is provided at the lower end portion of the outer peripheral surface of the inner cylinder portion 9b. 9c is formed. The height of the step portion 9c in the rotation axis direction of the rotor member 2 is substantially the same as the height of the top surface of the support portion 7b in the circumferential direction. Further, the rotor body 9 is integrally formed with a connector portion 9d protruding upward, and the movable side joint 2a is disposed inside the connector portion 9d. The rotor snap 10 is integrated with the inner cylinder portion 9 b of the rotor body 9 by snap coupling, and the rotor snap 10 is slidably engaged with the lower surface of the bottom plate portion 8, so that the rotor is fixed to the stator member 1. The member 2 is rotatably connected. When the stator member 1 and the rotor member 2 are connected to each other, the outer cylindrical portion 7 and the bottom plate portion 8 of the stator member 1 and the top plate portion 9a and the inner cylindrical portion 9b of the rotor body 9 are ring-shaped annular spaces in plan view. 3 is defined. A pair of engaging pins 9e are provided upright on the top surface of the top plate portion 9a, and the rotor member 2 is connected to the handle side via these engaging pins 9e.

  The two flat cables 4 and 5 are belt-shaped bodies in which a conductor is supported on an insulating film made of PET (polyethylene terephthalate) or the like. As shown in FIG. 3, in the annular space 3, the flat cables 4 and 5 are reversed in winding direction at the openings 61 and 62 of the holder 6, respectively. That is, one flat cable 4 is formed with a U-shaped reversing portion 4a that passes through the opening 61 so as to be wound around a roller 11 rotatably attached to the holder 6, and the other flat cable 4 5 is formed with a U-shaped reversal portion 5 a that passes through the opening 62 so as to be wound around a predetermined cylindrical body 6 b erected on the holder 6. The flat cable 4 in which the winding direction is reversed by the opening 61 having a small opening width in the circumferential direction is wound around the roller 11 disposed on the inner side of the reversing portion 4 a, and the rotational driving force is applied to the holder 6. The flat cable 5 that has a function of imparting, but whose winding direction is reversed by the opening 62 having a larger opening width in the circumferential direction than the opening 61 has a function of imparting a rotational driving force to the holder 6. Not done. Thus, in the case of a rotary connector having a plurality of flat cables, the roller rotates only inside the reversing part of the flat cable that gives a rotational driving force to the holder, in other words, only to the opening part having a small opening width in the circumferential direction. Can be freely attached to the holder. In the case of a single flat cable, the roller is rotatably attached to the holder only inside the reversing part of the flat cable. One end of each flat cable 4, 5 is connected to a fixed side joint 1 a provided on the stator member 1, and the other end of each flat cable 4, 5 is the movable side provided on the rotor member 2. It is connected to the joint 2a. Thereby, the electrical components provided on the steering column side and the electrical components provided on the handle side can be electrically connected via the flat cables 4 and 5.

  The holder 6 is made of synthetic resin and supports one roller 11 so as to be rotatable. The holder 6 is provided with an annular base portion 6a that is externally inserted into the step portion 9c of the inner cylinder portion 9b of the rotor body 9, five cylindrical bodies 6b that are erected in a circumferential direction, and a roller 11 And a support shaft 6c. The holder 6 includes a guide wall 6d that forms the opening 61 between the roller 11 and a guide wall 6e that forms the opening 62 between the predetermined cylindrical body 6b. ing. Furthermore, the holder 6 has cantilever-like elastic arm portions 6f that protrude outward in the radial direction of the annular base portion 6a in three cylindrical bodies 6b formed so as to be arranged at equal intervals in the circumferential direction. is doing. The annular base portion 6a is formed so that its inner edge portion is rotatably engaged and held by the step portion 9c of the inner cylinder portion 9b, and its outer edge portion forms a meat stealing portion 6h having a concave shape in plan view between the cylindrical bodies 6b. ing. As shown in FIG. 2, each elastic arm 6f is in contact with the tip of the bottom plate 8 of the stator member 1 and each elastic arm 6f is elastically deformable. The holder 6 is pressed against the lower surface of the stepped portion 9c by the reaction force of the portion 6f, thereby suppressing the vibration of the holder 6 in the rotation axis direction of the rotor member 2 and making it difficult to generate vibration noise. A bottom projection 6g is formed on the bottom surface of the annular base portion 6a, and the bottom projection 6g is a bottom plate portion together with the distal end portion of each elastic arm portion 6f when a large vibration is applied in the rotation axis direction of the rotor member 2. Hit the top of 8. Further, as shown in FIG. 5, the outer wall portion 6b1 of the cylindrical body 6b forms a first curved surface portion that protrudes radially outward of the holder 6, and this outer wall portion 6b1 has a first gap C1. The inner wall portion 6b2 of the cylindrical body 6b is a second curved surface portion that protrudes outward in the radial direction of the holder 6, and the inner wall portion 6b2 is a second curved surface portion. This is opposed to the outer peripheral surface of the inner cylinder portion 9b with a gap C2. A portion of the flat cables 4 and 5 wound around the inner peripheral surface of the outer cylinder portion 7 is disposed in the first gap C1, and an inner cylinder of the flat cables 4 and 5 is disposed in the second gap C2. The part wound around the outer peripheral surface of the part 9b is arranged. Then, the deflection of the flat cables 4 and 5 in the first gap C1 toward the inner cylinder portion 9b is restricted by the outer wall portion 6b1 of the cylindrical body 6b, and the flat cables 4 and 5 in the second gap C2 are. Is bent by the inner wall 6b2 of the cylindrical body 6b.

  The rotary connector configured as described above is installed in a steering apparatus of an automobile with the stator member 1 installed on the steering column and the rotor member 2 connected to the steering wheel, and an air bag inflator and a horn circuit mounted on the steering wheel. It is used as an electrical connection means. In use, when the driver rotates the handle clockwise or counterclockwise, the rotor member 2 to which the rotational force is transmitted rotates in the same direction.

  For example, when the rotor member 2 rotates counterclockwise in FIG. 3 from the neutral position of the handle, the reversing portions 4a and 5a of the flat cables 4 and 5 move counterclockwise by a smaller rotation amount than the rotor member 2, The holder 6 also moves in the same direction following the reversing parts 4a and 5a. At this time, the reversing portion 4a of the flat cable 4 passing through the opening 61 is wound around the outer peripheral surface of the inner cylinder portion 9b while being looped around the roller 11, pressing the roller 11 counterclockwise, and passing through the opening 62. Since the reversing portion 5a of the flat cable 5 does not abut against the nearby cylindrical body 6b, the holder 6 receives the rotational driving force only from the reversing portion 4a of the flat cable 4. Then, the flat cables 4 and 5 having a length approximately twice the moving amount of the reversing parts 4a and 5a are drawn out from the first gap C1 side and wound around the outer peripheral surface of the inner cylinder part 9b.

  Contrary to the above, when the rotor member 2 rotates clockwise from the neutral position of the handle, the reversing portions 4a and 5a of the flat cables 4 and 5 move clockwise by a smaller rotation amount than the rotor member 2. The holder 6 also moves in the same direction following the reversing parts 4a and 5a. At this time, the inversion part 4a of the flat cable 4 passing through the opening 61 presses the guide wall 6d in the clockwise direction, but the inversion part 5a of the flat cable 5 passing through the opening 62 does not contact the guide wall 6e. Therefore, the holder 6 receives the rotational driving force only from the reversing part 4 a of the flat cable 4. Then, the flat cables 4 and 5 having a length approximately twice the moving amount of the reversing parts 4a and 5a are drawn out from the second gap C2 side and are rewound onto the inner peripheral surface of the outer cylinder part 7.

  As described above, the rotary connector according to the present embodiment causes the outer wall 6b1 of the cylindrical body 6b standing on the holder 6 to bend the flat cables 4 and 5 toward the inner cylinder 9b in the first gap C1. Since the inner wall portion 6b2 of the cylindrical body 6b can regulate the bending of the flat cables 4 and 5 toward the outer tube portion 7 in the second gap C2, only one roller 11 is attached to the holder 6. However, a required rotational driving force can be applied to the holder 6 by the reversing portion 4a of the flat cable 4 that passes through the opening 61 having a small opening width in the circumferential direction, and cost reduction can be easily realized. . In addition, the holder 6 is configured so that the outer wall 6b1 and the inner wall 6b2 are distributed in the circumferential direction by disposing a plurality of cylindrical bodies 6b in the circumferential direction. It is easy to reduce the number of rollers 11 and reduce the weight. Therefore, this rotary connector can always rotate the holder 6 smoothly by the reversing part 4a of the flat cable 4, and the number of parts of the entire holder 6 including the roller 11 is small, and the assemblability is improved.

  In this embodiment, the holder 6 has cantilever-like elastic arm portions 6 f at three positions equally spaced in the circumferential direction, and the tip portions of these elastic arm portions 6 f are the bottom plate portions of the stator member 1. Since it is mounted on 8, the attitude | position of the holder 6 on the baseplate part 8 is stabilized, and the contact area is also suppressed. Therefore, consideration is also given so that the holder 6 can smoothly rotate from this point.

  Further, the rotary connector according to the present embodiment has the inner edge portion of the annular base portion 6a of the holder 6 rotatably engaged with the step portion 9c of the inner tube portion 9b, and the inner wall side of the outer tube portion 7, That is, the lower ends of the flat cables 4 and 5 in the first gap C1 are substantially the same as the lower ends of the flat cables 4 and 5 on the annular base portion 6a in the outer wall side of the inner cylinder portion 9b, that is, in the second gap C2. Since the support portion 7b is formed so as to be supported at a height, the lower ends of the flat cables 4 and 5 are held at substantially the same height in the annular space 3, and the flat cables 4 and 5 undulate in the vertical direction. It is wound in the annular space 3 with a stable posture. Therefore, the rotational driving force by the reversing part 4a can be efficiently applied to the holder 6, and the holder 6 can be rotated more smoothly.

  In the above embodiment, the case where the two flat cables 4 and 5 are accommodated and wound in the annular space 3 has been described. However, even if only one flat cable or three or more flat cables are used, the present embodiment may be used. The invention is applicable.

  In the above-described embodiment, the case where both the outer wall 6b1 and the inner wall 6b2 of the holder 6 that restricts the bending of the flat cable are formed in the hollow cylindrical body 6b has been described. If the outer wall portion 6b1 and the plurality of inner wall portions 6b2 are erected in the circumferential direction, substantially the same effect can be expected without forming a cylindrical body. In other words, the outer wall 6b1 is formed along a plurality of first curved surface portions that protrude radially outward of the holder 6, and the inner wall 6b2 is protruded radially inward of the holder 6. If formed along the second curved surface portion, the flat cable can be smoothly slid relative to the outer wall portion and the inner wall portion.

DESCRIPTION OF SYMBOLS 1 Stator member 2 Rotor member 3 Annular space 4,5 Flat cable 4a, 5a Inversion part 6 Holder 6a Annular base part 6b Cylindrical body 6b1 Outer side wall part 6b2 Inner side wall part 6c Support shaft 6d, 6e Guide wall 6f Elastic arm part 6h Meat stealing Part 7 Outer cylinder part 7b Support part 8 Bottom plate part 9 Rotor body 9a Top plate part 9b Inner cylinder part 9c Stepped part 10 Rotor snap 11 Roller 61, 62 Opening part C1 First gap C2 Second gap

Claims (4)

A stator member having an outer cylinder part and a bottom plate part; a rotor member having an inner cylinder part facing the outer cylinder part and rotatably supported by the stator member; the outer cylinder part and the inner cylinder part; In the annular space defined between the flat cable in which the winding direction is reversed in the middle, both ends of which are fixed to the stator member and the rotor member, respectively, and rotatable in the annular space A rotary connector provided with a holder having an opening through which an inversion portion of the flat cable passes,
The holder has an annular base portion that is extrapolated to the inner cylinder portion and is placed on the bottom plate portion, and an annular base portion that is erected on the annular base portion and has a first gap from the inner peripheral surface of the outer cylinder portion. A plurality of opposing outer wall portions, a plurality of inner wall portions standing on the annular base portion and facing the outer peripheral surface of the inner cylinder portion with a second gap, and rotatable inside the reversing portion With attached rollers,
The inner cylinder portion has a stepped portion that rotatably engages with an inner edge portion of the annular base portion, and the outer cylinder portion has a support portion, and the support portion is formed of the flat cable in the first gap. A rotary connector characterized in that a lower end portion and a lower end portion of the flat cable on the annular base portion are supported at substantially the same height in the second gap. In Claim 1, The said outer side wall part is formed from the 1st curved surface part convex toward the radial direction outer side of the said holder, and the said inner wall part is convex toward the radial direction inner side of the said holder A rotary connector formed from a second curved surface portion. 3. The method according to claim 2, wherein each of the plurality of first curved surface portions and the plurality of second curved surface portions is formed of a plurality of cylindrical bodies standing in a distributed manner in the circumferential direction, and the cylindrical bodies are continuously provided. A rotary connector characterized by that. 4. The plurality of elastic members according to claim 1, wherein the holder protrudes radially outward from the plurality of locations at substantially equal intervals in the circumferential direction, and the tip of the holder comes into contact with the bottom plate portion. A rotary connector having an arm portion.

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