CN100399644C - Rotary connector - Google Patents

Abstract

To provide a swivel joint capable of precisely resin-molding a position limiting portion of a movable side cover relative to a fixed side cover, and which is less likely to generate noise during rotation due to changes in temperature or aging. The structure of the rotary joint is as follows: a housing; a cover; a rotor with a top plate and a first cylindrical portion; The second cylindrical portion snap-fitted with the cylindrical portion; a flexible cable that can be wound up and unwound within the housing; and an annular plate portion. Between the lower end of the first cylindrical part and the locking part, a holding protrusion is provided to protrude outward in the radial direction from the outer peripheral surface of the second cylindrical part, and is provided in a state where a step is formed on the inner edge of the upper surface of the cover. The holding step has a stepped wall facing the side of the holding protrusion, and the inner edge of the cover is rotatably clamped by the lower surface of the holding protrusion and the upper surface of the annular plate.

Description

Swivel joint

technical field

The present invention relates to a swivel joint for electrically connecting an electrical device on a steering wheel to an electrical device on a vehicle body, and more particularly to a connection structure between a fixed side cover and a movable side cover.

Background technique

In the past, as shown in FIG. 5 , a known rotary joint has: a fixed side cover 103 having a cylindrical casing 101 and an annular cover 102 covering one end of the casing 101; a movable side cover 106 having a cover The annular top plate portion 104 at the other end of the housing 101 and the first cylindrical portion 105 erected downward from the inner peripheral end of the top plate portion 104; 102, the annular locking portion 107 on the outer surface, the second cylindrical portion 108 standing up from the inner peripheral end of the locking portion 107, and the second cylindrical portion 108 connected to the second cylindrical portion 108 and connected to the steering shaft (not shown). 3. The cylindrical part 109 is rotatably attached to the movable side cover 106 relative to the fixed side cover 103 by combining the second cylindrical part 108 with the first cylindrical part 105; In the annular space formed by the combination of the fixed side cover 103 and the movable side cover 106; the roller 112 is freely rotatably installed on the ring bracket 111; the flexible cable 113 is wound on the roller 112, and one end It is connected to the movable side cover 106, and the other end is connected to the fixed side cover 103 (for example, refer to Patent Document 1).

Since the rotary joint is opposite to the annular protruding portion 114 disposed on the inner surface of the casing 101 and the annular recessed portion 115 disposed on the lower surface of the top plate portion 104, and the lower surface of the cover body 102 is connected to the locking portion 107 The upper surface of the upper surface is opposed to define the position of the movable cover 106 relative to the fixed cover 103 in the direction of the rotation axis, and the annular protrusion 114 is engaged with the annular recess 115, and because the side surface of the locking part 107 Opposing to the stepped wall portion 116 bent and formed on the inner edge of the cover body 102 , the radial position of the movable cover body 106 relative to the fixed cover body 103 is defined.

As a result, the movable side cover 106 is held rotatably relative to the fixed side cover 103, the fixed side cover 103 is fixed to the stator portion on the vehicle body side, and the movable side cover 106 is connected to the steering wheel. , the electrical device provided on the vehicle body and the electrical device provided on the steering wheel can be electrically connected through the flexible cable 113 .

Patent Document 1 Japanese Patent Laid-Open No. 2003-174715

However, since conventional rotary joints are injection-molded with insulating resin, it is more difficult to mold the resin with high precision at the part that is separated from the rotary shaft in the radial direction, and because of aging changes, The deformation becomes large, and when the movable side cover 106 rotates, the distance in the radial direction from the rotation axis is relatively large, and the opposite annular protruding portion 114 is in sliding contact with the annular concave portion 115, which is likely to generate noise. question.

Contents of the invention

The object of the present invention is to solve the problems of the prior art, and to provide a rotary joint in which the position limiting portion of the movable-side cover relative to the fixed-side cover can be resin-molded with high precision, and the rotary joint can be used even due to temperature changes or aging. The deformation is caused by the change, and it is not easy to generate noise when the movable cover rotates.

In order to solve the above technical problems, the present invention has the following structure: a fixed side cover with a cylindrical casing and an annular cover covering the lower open end of the casing; a movable side cover with a cover covering the casing. The ring-shaped top plate part of the upper open end of the body and the first cylindrical part extending downward from the inner peripheral end of the top plate part; The second cylindrical part of the shape part, and is equipped with a locking part, and the locking part has a claw protruding outward in the radial direction from the lower end of the second cylindrical part; the storage space is formed by moving the movable A side cover is rotatably assembled to the fixed side cover to be formed between the movable side cover and the fixed side cover; a flexible cable connects the fixed side cover in the storage space The side cover and the movable side cover are electrically connected; the ring-shaped plate part is locked on the locking part, and between the lower end of the first cylindrical part and the locking part, from the The outer peripheral surface of the second cylindrical part is provided with a holding protrusion protruding outward in the radial direction, and a holding step is provided in a state of forming a step on the inner edge of the upper surface of the cover. The sides of the holding protrusions are opposite to each other, and the inner edge of the cover is rotatably clamped by the lower surface of the holding protrusions and the upper surface of the annular plate portion.

In this way, the movable side can be defined by the part near the rotation axis of the movable side cover by sandwiching the cover between the holding protrusion and the annular plate part, and the side surface of the holding protrusion is opposed to the wall surface of the holding step part. The axial position and the radial position of the cover with respect to the fixed side cover, therefore, the position limiting part of the movable side cover with respect to the fixed side cover can be resin molded with high precision, and temperature changes and time changes can be adjusted. The influence of the induced deformation is suppressed to be small, and the generation of noise when the movable side cover rotates can be suppressed.

In addition, in the swivel joint of the present invention, the accommodating space is rotatably accommodated with a ring-shaped bracket, and the ring-shaped bracket shaft supports rollers that change the winding direction of the flexible cable. The inner end of the bracket is rotatably clamped between the lower surface of the first cylindrical portion and the upper surface of the holding protrusion, and is pivotally supported by the second cylindrical portion.

In this way, since the ring-shaped bracket is provided in the storage space, and the rollers for reversing the flexible cable are mounted on the ring-shaped bracket, if the ring-shaped bracket is pivotally supported on the second cylindrical part where the rotor snaps, it can The flexible cable can be smoothly wound up or unwound, and the generation of noise when the movable side cover is turned can be suppressed.

In addition, in the swivel joint of the above-mentioned structure of the present invention, the cover body is provided with an engaging step portion in a state where a step difference is formed on the inner edge of the lower surface of the cover body, and the wall surface of the engaging step portion is in contact with the ring. The sides of the plate portion are opposite to each other.

According to this structure, the height dimension of the rotary joint can be reduced only to the extent corresponding to the height dimension of the engaging step portion, and the thickness of the rotary joint can be reduced.

In addition, in the swivel joint of the above-mentioned structure of the present invention, the ring-shaped bracket has an elastic portion that exerts an elastic action on the upper surface of the cover.

According to such a configuration, rattling of the ring-shaped bracket portion in the direction of the rotary shaft can be suppressed, and rattling sound can be reduced when the rotary joint vibrates in the vertical direction.

In addition, in the swivel joint of the present invention, the annular plate portion has a cam portion that is detachably engaged with the locking portion and that protrudes from the lower side in the direction of the rotary shaft.

According to this structure, since the cam portion for the connection release mechanism is provided on the annular plate portion, the structure of the connection portion connected to the cam portion can be made the same as that of various release mechanisms ( Corresponding to the Kyancell mechanism), the components of the fixed side cover and the movable side cover can be shared, and the cost of the rotary joint with the release component can be reduced.

In addition, in order to solve the above-mentioned technical problems, the present invention has a structure comprising: a fixed side cover having a cylindrical casing and an annular cover covering the lower open end of the casing; a movable side cover having a The ring-shaped top plate at the upper open end of the housing and the first cylindrical portion extending downward from the inner peripheral end of the top plate; The second cylindrical part of the first cylindrical part is equipped with a locking part, and the locking part has claws protruding outward in the radial direction from the lower end of the second cylindrical part; the storage space is formed by placing the The movable side cover is rotatably assembled into the fixed side cover and divided into; a flexible cable electrically connects the fixed side cover and the movable side cover in the storage space; An annular plate portion, which is locked to the locking portion, protrudes radially outward from the outer peripheral surface of the second cylindrical portion between the lower end of the first cylindrical portion and the locking portion. There is a holding protrusion, and the inner edge of the cover is rotatably clamped by the lower surface of the holding protrusion and the upper surface of the annular plate portion, and a narrow spacer is provided on the inner edge of the cover. The gap is a stepped wall surface facing the side surface of the holding protrusion or the side surface of the annular plate portion.

According to this configuration, since the axial position and the radial position of the movable side cover relative to the fixed side cover can be defined by the part near the rotation axis of the movable side cover, it is possible to move the movable side cover relative to the fixed side cover. The position regulating portion of the side cover is resin molded with high precision, and the influence of deformation due to temperature change and aging change can be suppressed to be small, and the generation of noise when the movable side cover rotates can be suppressed.

In addition, in the swivel joint of the present invention, an engaging step portion capable of accommodating the outer peripheral portion of the annular plate portion is provided on the inner edge of the lower surface of the cover body, and the step difference of the engaging step portion The wall surface is opposed to a side surface of the annular plate portion.

According to this structure, the height dimension of the rotary joint can be reduced only to the extent corresponding to the height dimension of the engaging step portion, and the thickness of the rotary joint can be reduced.

In addition, in the swivel joint of the present invention, a retaining step capable of accommodating the outer peripheral portion of the retaining protrusion is provided on the inner edge of the upper surface of the cover, and the stepped wall surface of the retaining step is different from the wall surface of the retaining step. Keep the raised sides facing each other.

According to such a configuration, the height dimension of the rotary joint can be reduced only to the extent corresponding to the height dimension of the holding step portion, and the thickness of the rotary joint can be reduced.

In addition, in the swivel joint of the present invention, the annular plate portion has a cam portion that is detachably engaged with the locking portion and that protrudes from the lower side in the direction of the rotary shaft.

According to this structure, since the cam portion for the connection release mechanism is provided on the annular plate portion, the structure of the connection portion connected to the cam portion can be changed from that of various release mechanisms by only replacing the annular plate portion. Correspondingly, the parts of the fixed side cover and the movable side cover can be shared, and the cost of the rotary joint with the release part can be reduced

The effect of the invention

The rotary joint of the present invention includes: a fixed side cover having a cylindrical case and an annular cover covering the lower open end of the case; a movable side cover having a ring covering the upper open end of the case. A top plate portion and a first cylindrical portion extending downward from the inner circumference of the top plate portion; the rotor is snap-locked and has a second tube inserted from below the cover and connected to the first cylindrical portion shaped part, and has a claw locking part protruding radially outward from the lower end of the second cylindrical part; a storage space, which is formed by rotatably assembling the movable side cover to the fixed side cover body; a flexible cable, which electrically connects the fixed side cover and the movable side cover in the storage space; the ring-shaped plate part, which is locked on the locking part, Between the lower end of the first cylindrical portion and the locking portion, a holding protrusion is provided to protrude outward in the radial direction from the outer peripheral surface of the second cylindrical portion so as to fit inside the upper surface of the cover. A holding step is provided in a state where a step is formed on the edge, and the stepped wall surface of the holding step is opposed to the side surface of the holding protrusion, and can be moved by the lower surface of the holding protrusion and the upper surface of the annular plate portion. Rotately clamp the inner edge of the cover, so that the cover is clamped between the holding protrusion and the annular plate portion, by making the side surface of the holding protrusion and the wall surface of the holding step facing each other, the movable side cover can The portion near the rotation axis of the body defines the axial position and the radial position of the movable side cover relative to the fixed side cover, and the position limiting part of the movable side cover relative to the fixed side cover can be precisely resin-molded, In addition, the influence of deformation caused by temperature change and aging change can be suppressed to be small, and the generation of noise when the movable side cover rotates can be suppressed.

Furthermore, since the rotary joint of the present invention includes: a fixed side cover having a cylindrical case and an annular cover covering the lower open end of the case; a movable side cover having a cover covering the upper open end of the case. An annular top plate portion and a first cylindrical portion extending downward from the inner circumference of the top plate portion; the rotor is snap-locked, and has a second cylindrical portion inserted from below the cover and connected to the first cylindrical portion. a cylindrical part, and has a locking part, and the locking part has a claw protruding outward from the lower end of the second cylindrical part in the radial direction; the storage space is formed by turning the movable side cover Assembled into the fixed side cover and divided into: a flexible cable, which electrically connects the fixed side cover and the movable side cover in the storage space; stop at the locking portion, and in such a swivel joint, between the lower end of the first cylindrical portion and the locking portion, protrude radially outward from the outer peripheral surface of the second cylindrical portion There is a holding protrusion, and the inner edge of the cover is rotatably clamped by the lower surface of the holding protrusion and the upper surface of the annular plate portion, and a narrow gap is provided on the inner edge of the cover. The gap is a stepped wall surface opposite to the side of the holding protrusion or the side of the annular plate portion, so the position of the movable side cover relative to the fixed side cover can be limited by the part near the rotation axis of the movable side cover. Axial position and radial position. Therefore, the position regulating portion of the movable side cover relative to the fixed side cover can be resin molded with high precision, and the influence of deformation caused by temperature changes and time changes can be suppressed to a small size, and the movable side cover can be suppressed from being damaged. Occurrence of noise when the body rotates.

Description of drawings

Fig. 1 is an exploded perspective view of a rotary joint according to a first embodiment.

Fig. 2 is a cross-sectional view of an essential part of the rotary joint according to the first embodiment.

Fig. 3 is a sectional view of main parts of a rotary joint according to a second embodiment.

Fig. 4 is a cross-sectional view of an essential part of a rotary joint according to a third embodiment.

Fig. 5 is a sectional view of a conventional rotary joint.

Detailed ways

Hereinafter, a first embodiment of a rotary joint according to the present invention will be described with reference to FIGS. 1 and 2 . FIG. 1 is an exploded perspective view of a rotary joint according to this embodiment, and FIG. 2 is a sectional view of main parts of the rotary joint according to this embodiment.

As shown in Figure 1, the rotary joint of this embodiment mainly includes a housing 1, a cover 2, a rotor (movable side cover) 3, a rotor snap lock 4, a release member 5, a flexible cable 6, a ring Support 7, roller 8. All other components except the flexible cable 6 are formed of insulating resin.

The casing 1 is formed into a cylindrical shape of a required size, and at the lower part of its outer peripheral surface, a first engaging part 11 for snap-fitting the cover body 2 and a stator part for fixing the casing 1 to the automobile are formed. The mounting protrusions 12. In addition, an annular protruding portion 13 protrudes radially inwardly on the inner peripheral surface of the housing 1 , and an annular protrusion 14 protrudes upward on the upper surface thereof as shown in FIG. 2 .

The cover body 2 is formed in a ring shape in a state capable of covering the lower open end of the housing 1, and has a first engaging portion 11 formed on the outer peripheral surface of the outer peripheral surface that engages with the first engaging portion 11 formed on the lower portion of the outer peripheral surface of the housing 1. The locking claw 21 and the setting part 22 of the external connection joint. In addition, on the inner edge of the upper surface of the cover body 2, a holding protrusion 44 formed on the outer periphery of the second cylindrical portion 41 of the rotor snap 4 described later is formed so as to be rotatably engaged. The retaining step portion 23 that becomes a step difference is formed on the inner edge of the lower surface of the cover body 2 in a state of being rotatably engaged with an annular plate portion 51 described later to become a step difference. Step part 24. In this way, the holding step 23 becomes a step standing downward from the upper surface of the inner edge of the upper surface of the cover 2 , and the engaging step 24 becomes a step downward from the inner edge of the lower surface of the cover 2 . A step that rises upward from the surface. Here, the annular plate portion 51 restricts the movement of the rotor (movable side cover) 3 to the upper side in the rotation axis direction relative to the fixed side cover.

The housing 1 and the cover 2 are integrated by snap-fitting the first locking claw 21 to the first engaging portion 11 to form a fixed-side cover.

The rotor 3 has an annular top plate portion 31 capable of covering the upper open end of the housing 1 , and a first cylindrical portion 32 extending downward from the inner periphery of the top plate portion 31 . On the outer edge of the lower surface of the top plate 31, there is an annular recess 33 that engages with the annular protrusion 14 of the housing 1 with a large gap, and on the upper surface of the top plate 31 is formed a mounting portion 34 for an external connection joint and for Connect the rotor 3 to the connecting protrusion 35 on the steering wheel. In addition, a plurality of second locking claws 37 are formed at the lower end portion of the inner peripheral surface of the first cylindrical portion 32 at predetermined intervals in the same direction as shown in FIG. 2 .

The rotor snap 4 has a second cylindrical portion 41 inserted into and connected to the first cylindrical portion 32 from below the cover body 2 , and a plurality of locking portions protruding downward from the lower end of the second cylindrical portion 41 . 42 and a plurality of rotation stop protrusions 45. As shown in FIG. 2 , claws protruding outward in the radial direction are formed on the front end of the locking portion 42 . Here, since the radial dimension of the outer surface of the locking portion 42 is set to be smaller than the radial dimension of the inner surface of the cover body 2, the rotor snap-fit 4 can be fitted into the swivel joint when assembling the swivel joint. The rotor 3 in the housing 1 is snap-fitted, and then the housing 1 and the cover 2 are connected in a state where the wall surface of the holding step 23 and the outer surface of the holding protrusion 44 face each other and are joined together. Therefore, since the wall surface constituting the step of the holding step 23 and the side surface of the holding protrusion 44 facing each other with a narrow gap can be combined without damage, the radius of the movable side cover relative to the fixed side cover can be accurately defined. orientation position. In addition, as can be seen from FIG. 2 , the radial dimension of the wall surface of the holding step portion 23 is larger than the radial dimension of the inner surface of the cover body 2 .

In addition, the second cylindrical portion 41 has a second engaging portion 43 for snap-fitting and coupling with the second locking claw 37 of the first cylindrical portion 32 , and a retaining portion formed on the inner edge of the upper surface of the cover body 2 . The step portion 23 is rotatably engaged with the holding protrusion 44 . Here, the holding protrusion 44 protrudes outward in the radial direction from a position between the lower end of the first cylindrical portion 32 and the annular locking portion 42 on the outer peripheral surface of the second cylindrical portion 41 . Therefore, as shown in FIG. 2, since the side surface of the holding protrusion 44 is opposed to the wall surface formed by the holding step portion 24 of the cover 2 with a narrow gap therebetween, it can be reversed by the return of the rotor 3 (movable side cover). The portion near the rotation axis defines the radial position of the movable side cover relative to the fixed side cover. Therefore, these position limiting portions can be resin-molded with high precision, and the influence of deformation caused by temperature changes and aging changes can be suppressed to a small extent.

The annular plate portion 51 has an engaging portion 53 that engages with the locking portion 42 formed at the lower end of the rotor snap 4, and also has a notch portion 54 that engages with the rotation stop protrusion 45. In the locked state, it can be freely rotatably engaged with the engaging step portion 24 formed on the inner edge of the lower surface of the cover body 2. Here, the inner edge of the cover body 2 is clamped by the upper surface of the annular plate portion 51 and the lower surface of the holding protrusion 44 of the rotor snap 4 with a narrow gap therebetween, thereby defining the position of the movable side cover relative to the fixed side cover. The axial position of the body. In addition, since the annular plate portion 51 does not limit the radial position of the movable side cover relative to the fixed side cover, the step difference between the outer surface of the annular plate portion 51 and the engaging step portion 24 can be set relatively large. There is no gap between the walls, and there will be no sliding sound in this part. Furthermore, as shown in FIGS. 1 and 2, the annular plate portion 51 is vertically provided with a cam portion 52 downward from the lower end of the annular plate portion 51, and constitutes the release member 5. 54, so that the annular plate portion 51 can be fixed without moving in the circumferential direction with respect to the rotor 3, and can be engaged with a release mechanism not shown to perform a stable release operation. In addition, when the ring-shaped plate part 51 does not have the function as the release member 5, the cam part 52 can be omitted of course. Furthermore, the dimension in the radial direction from the axis of rotation of the annular plate portion 51 is set with a relatively large gap with respect to the dimension in the radial direction from the axis of rotation of the wall surface constituting the step of the engaging step portion 24 . Certainly.

The flexible cable 6 is formed by laminating a plurality of foil-shaped conductors with an insulating film to form a desired length, and it can be wound or unwound and accommodated in a combination of the housing 1, the cover 2, and the rotor 3. In the formed ring-shaped space. In addition, in Fig. 1 and Fig. 2, the example that has two flexible cables 6 is illustrated, but there is no limitation on the number of flexible cables 6, and there may be one or more than two flexible cables. cable6. Both ends of the flexible cable 6 are connected to unillustrated external connectors provided on the cover 2 and the rotor 3 , and signals flowing through the flexible cable 6 are led out to the outside through the external connectors.

The ring bracket 7 has a ring-shaped base plate 71 , a plurality of roller holding portions 72 and a cable winding portion 73 formed on one side of the base plate 71 , and an elastic portion 74 for exerting an elastic action on the base plate 71 to the upper surface of the cover body 2 . . On the other hand, the roller 8 is formed in a cylindrical shape, and is rotatably attached to the roller holding portion 72 . These annular brackets 7 and rollers 8 are rotatably accommodated in an annular space formed by combining the housing 1 , the cover 2 and the rotor 3 . The flexible cable 6 is wound on the cable winding portion 73 and the roller 8 in a desired manner, and is wound or unwound as the roller 3 rotates forward or reverse.

Hereinafter, a method of assembling the rotary joint according to the embodiment will be described.

First, both ends of the flexible cable 6 are respectively connected to external connection joints (not shown) provided on the cover body 2 and the rotor 3 .

Next, the cylindrical portion 32 of the rotor 3 is inserted into the casing 1, the top plate portion 31 of the rotor 3 is covered on the upper surface of the casing 1, and the flexible cable 6 is accommodated in the ring formed between the casing 1 and the rotor 3. inside the shape space.

Afterwards, the ring-shaped bracket 7 with the rollers 8 installed therein is packed into the ring-shaped space, and the flexible cable 6 can be wound up and unwound on the cable roll formed on the rollers 8 and the ring-shaped bracket 7. On the winding part 73.

Then, the second locking pawl 37 formed on the first cylindrical portion 32 of the rotor 3 is snap-engaged with the second engagement portion 43 formed on the second cylindrical portion 41 of the rotor snap 4, so that the rotor 3 is integrated with the rotor snap lock 4.

Next, the holding step portion 23 formed on the inner edge of the upper surface of the cover body 2 is brought into contact with the holding step portion 23 formed on the second cylindrical portion 41 of the rotor snap 4 , and the holding step portion 23 formed on the outer periphery of the case 1 The first engaging portion 11 on the lower surface snaps and engages with the locking pawl 21 formed on the outer peripheral surface of the cover body 2 , so that the cover body 2 is covered on the lower surface of the housing 1 .

Finally, the rotation stop protrusion 45 formed on the lower end portion of the rotor snap 4 is inserted into the notch 54 formed on the annular plate portion 51, and the locking portion 42 formed on the rotor snap 4 is connected with the locking portion 42 formed on the The engaging portion 53 on the annular plate portion 51 is snap-fitted, and the release member 5 is integrated with the housing 1 , the cover 2 and the rotor 3 .

Because the swivel joint of this embodiment clamps the inner edge of the cover body 2 with a narrow gap by the holding protrusion 44 and the annular plate 51, and makes the side surface of the holding protrusion 44 and the step forming the holding step portion 23 through a narrow gap. The walls face each other, so the axial position and the radial position of the movable side cover relative to the fixed side cover can be simultaneously defined by the part near the rotation axis of the rotor 3 (movable side cover), and the positions of these components can be adjusted. The restricting portion is resin molded with high precision, and the influence of deformation caused by temperature change and aging change can be suppressed to be small, and the generation of noise when the movable side cover rotates can be suppressed.

In addition, since the swivel joint of this embodiment installs the ring-shaped bracket 7 equipped with the roller 8 for reversing (reversing) the flexible cable 6 in the storage space, the ring-shaped bracket 7 is pivotally supported on the rotor snap-lock 4, the flexible cable 6 can be smoothly wound up or unwound, and the generation of noise when the movable side cover rotates can be suppressed.

In addition, since the rotary joint of this embodiment is provided with an engaging step portion 24 on the inner edge of the lower surface of the cover body 2, so that the wall surface of the engaging step portion 24 faces the side surface of the annular plate portion 51, it can reduce the The height dimension of the rotary joint corresponds to the height dimension of the engaging step portion 24, so that the thickness of the rotary joint can be reduced.

Moreover, since the rotary joint of this embodiment has the elastic portion 74 on the ring bracket 7 that exerts an elastic action on the upper surface of the cover body 2, it is possible to suppress the swing of the ring bracket 7 in the direction of the rotation axis, and when the rotary joint is up and down Even in the case of vibrating in the same direction, the rattling sound can be reduced.

In addition, since the rotary joint of this embodiment is provided with the cam portion 52 for the connection release mechanism on the annular plate portion 51, the structure of the connecting portion connected to the cam portion 52 can be made the same by only replacing the annular plate portion 51. Corresponding to various release mechanisms. Therefore, components of the fixed-side cover and the movable-side cover can be shared, and the cost of the rotary joint having the release member can be reduced.

In addition, in the above-mentioned embodiment, the fixed side cover is composed of the combination of the casing 1 and the cover body 2, but the gist of the present invention is not limited to this, and the fixed side cover may have a casing and a cover. One structure.

In addition, in the above-mentioned embodiment, the ring-shaped support 7 and the roller 8 are provided, but the gist of the present invention is not limited thereto, and may be omitted depending on how the flexible cable 6 is wound.

Next, a second embodiment of the present invention will be described with reference to FIG. 3 . Fig. 3 is a cross-sectional view of main parts of a rotary joint according to a second embodiment.

In the second embodiment, the same symbols as those in the first embodiment are assigned to the same members as in the first embodiment, and description thereof will be omitted. The difference between the second embodiment and the first embodiment is that no step portion (holding step portion 23 ) is formed on the inner edge of the upper surface of the cover body 2 to match the holding portion protrudingly provided on the outer peripheral surface of the second cylindrical portion 41 . The protrusion 44 is in contact with the inner edge of the upper surface of the cover body 2, and the step wall surface of the engagement step 24 is set opposite to the side surface of the annular plate part 51 through a narrow gap to set its size, thereby limiting the movable position. The radial position of the side cover relative to the fixed side cover.

Therefore, the method of assembling the rotary joint according to the second embodiment is to bring the upper surface of the cover body 2 into contact with the lower surface of the holding protrusion 44 formed on the second cylindrical portion 41 of the rotor snap 4, and to bring the upper surface of the cover 2 into contact with the lower surface of the holding protrusion 44 formed on the second cylindrical portion 41 of the rotor snap 4, and to make the upper surface of the cover 2 contact the lower surface of the holding protrusion 44 formed on the second cylindrical portion 41 of the rotor snap 4. The first engaging portion 11 on the lower portion of the outer peripheral surface of the body 1 snaps and engages with the first locking claw 21 formed on the outer peripheral surface of the cover 2 , so that the cover 2 is covered on the lower surface of the housing 1 .

In this way, in the rotary joint of the second embodiment, since the inner edge of the cover body 2 is sandwiched by the holding protrusion 44 and the annular plate 51 with a narrow gap, and the step of the side surface of the annular plate portion 51 relative to the engagement step portion 24 Since the differential wall faces face each other with a narrow gap, the axial position and the radial position of the movable side cover relative to the fixed side cover can be simultaneously defined by the portion near the rotation axis of the rotor 3 (movable side cover). Therefore, the position regulating parts of these components can be resin-molded with high precision, and the influence of deformation due to temperature changes and aging changes can be suppressed to be small, and the generation of noise when the movable side cover rotates can be suppressed.

In addition, since the rotary joint of this embodiment is provided with an engagement step 24 on the inner edge of the lower surface of the cover body 2, so that the wall surface of the engagement step 24 faces the side surface of the annular plate portion 51, it can reduce the The height dimension of the rotary joint corresponds to the height dimension of the engaging step portion 24, so that the thickness of the rotary joint can be reduced.

In addition, since the rotary joint of this embodiment is provided with the cam part 52 for connecting the release mechanism to the annular plate part 51, it can correspond to various release mechanisms only by replacing the ring plate part 51. Therefore, components of the fixed-side cover and the movable-side cover can be shared, and the cost of the rotary joint having the release member can be reduced.

Next, a third embodiment of the rotary joint of the present invention will be described with reference to FIG. 4 . Fig. 4 is a cross-sectional view of main parts of a rotary joint according to a third embodiment.

The characteristic of the rotary joint of this example is that, as shown in FIG. 4, a holding step 23 is formed on the inner edge of the upper surface of the cover body 2, and the outer peripheral portion of the holding protrusion 44 formed on the rotor snap 4 can be accommodated instead of the holding protrusion 44 shown in FIG. 3 shows a structure in which an engaging step portion 24 is formed on the inner edge of the lower surface of the cover body 2 .

The stepped wall surface of the holding step portion 23 is formed to face the side surface of the holding protrusion 44 formed on the rotor snap 4 with a narrow gap when the cover 2 and the rotor snap 4 are assembled. In addition, the stepped bottom surface of the step portion 23 is held so that when the cover 2, the rotor snap 4 and the release member 5 are assembled, the inner edge of the cover 2 is formed on the lower surface of the holding protrusion 44 of the rotor snap 4 and provided in the release position. The ring-shaped plate portion 51 of the member 5 is formed in a state of sandwiching a narrow gap therebetween.

Since the rotary joint of this example clamps the inner edge of the cover body 2 with a narrow gap between the lower surface of the holding protrusion 44 formed on the rotor snap 4 and the upper surface of the annular plate portion 51, the movable side cover is defined. The axial position of the body relative to the fixed side cover, and the stepped wall surface of the holding step 23 and the side surface of the holding protrusion 44 are arranged opposite to each other with a narrow gap, thereby defining the position of the movable side cover relative to the fixed side cover. Therefore, the axial position and the radial position of the movable side cover relative to the fixed side cover can be defined by the portion near the rotation axis of the movable side cover. Therefore, similarly to the rotary joint of the first embodiment, each position limiting portion can be resin-molded with high precision, and the influence of deformation caused by temperature change and aging change can be suppressed to be small, and the movement of the movable side can be suppressed. Noise occurs when the cover rotates.

In addition, in the above-mentioned embodiment, the fixed side cover is composed of the combination of the case 1 and the cover 2, but the gist of the present invention is not limited to this, and the fixed side cover may have a case and a cover. One structure.

In addition, in the above-mentioned embodiment, the ring-shaped support 7 and the roller 8 are provided, but the gist of the present invention is not limited thereto, and they may be omitted depending on how the flexible cable 6 is wound.

Claims (13)

1. A rotary joint, characterized by: The fixed side cover has a cylindrical shell and an annular cover covering the lower open end of the shell; the movable side cover has an annular top plate covering the upper open end of the shell and a The first cylindrical part extending downward from the inner peripheral end; the rotor snaps, has a second cylindrical part inserted from below the cover and is connected to the first cylindrical part, and has a locking part, The locking portion has claws protruding outward in the radial direction from the lower end of the second cylindrical portion; the storage space is formed by rotatably assembling the movable side cover to the fixed side cover; formed between the movable side cover and the fixed side cover; a flexible cable electrically connecting the fixed side cover and the movable side cover in the storage space; and an annular plate portion, which is locked at the locking portion, Between the lower end of the first cylindrical portion and the locking portion, a holding protrusion is provided to protrude outward in the radial direction from the outer peripheral surface of the second cylindrical portion so as to fit inside the upper surface of the cover. A holding step is provided in a state where a step is formed on the edge, and the stepped wall surface of the holding step is opposed to the side surface of the holding protrusion, and can be moved by the lower surface of the holding protrusion and the upper surface of the annular plate portion. The inner edge of the cover is rotationally clamped. 2. The swivel joint according to claim 1, wherein the storage space is rotatably accommodated with a ring-shaped bracket that axially supports rollers, and the rollers change the winding direction of the flexible cable. The inner end of the ring holder is rotatably sandwiched between the lower surface of the first cylindrical portion and the upper surface of the holding protrusion, and is axially supported by the second cylindrical portion. 3. The rotary joint according to claim 1 or 2, characterized in that, the cover body is provided with an engaging step portion in a state where a step difference is formed on the inner edge of the lower surface of the cover body, and the wall surface of the engaging step portion It is opposite to the side surface of the annular plate portion. 4. The swivel joint according to claim 2, wherein the ring-shaped bracket has an elastic portion that exerts an elastic action on the upper surface of the cover. 5. The swivel joint according to claim 3, wherein the ring-shaped bracket has an elastic portion that applies elastic action to the upper surface of the cover. 6. The swivel joint according to claim 1 or 2, wherein the annular plate portion has a cam portion which is detachably engaged with the locking portion and protrudes from the lower side in the direction of the rotary shaft. . 7 . The swivel joint according to claim 3 , wherein the annular plate portion has a cam portion that is detachably engaged with the locking portion and protrudes from the lower side in the direction of the rotary shaft. 8 . The swivel joint according to claim 4 , wherein the annular plate portion has a cam portion which is detachably engaged with the locking portion and protrudes from the lower side in the direction of the rotary shaft. 9 . The swivel joint according to claim 5 , wherein the annular plate portion has a cam portion that is detachably engaged with the locking portion and protrudes from the lower side in the direction of the rotary shaft. 10. A rotary joint, characterized by: The fixed side cover has a cylindrical shell and an annular cover covering the lower open end of the shell; the movable side cover has an annular top plate covering the upper open end of the shell and a The first cylindrical part extending downward from the inner peripheral end; the rotor snaps, has a second cylindrical part inserted from the bottom of the cover, and is connected to the first cylindrical part, and has a locking part , the locking portion has claws protruding outward in the radial direction from the lower end of the second cylindrical portion; the storage space is formed by rotatably assembling the movable side cover to the fixed side cover, And formed between the movable side cover and the fixed side cover; a flexible cable electrically connects the fixed side cover and the movable side cover in the storage space; and an annular plate portion, which is locked at the locking portion, Between the lower end of the first cylindrical portion and the locking portion, a holding protrusion protrudes radially outward from the outer peripheral surface of the second cylindrical portion, and the lower surface of the holding protrusion and the The upper surface of the annular plate portion rotatably holds the inner edge of the cover, and the side surface of the holding protrusion or the annular plate portion is provided on the inner edge portion of the cover with a narrow gap. The side of the opposite step wall. 11. The swivel joint according to claim 10, wherein an engaging step portion capable of receiving the outer peripheral portion of the annular plate portion is provided on the inner edge of the lower surface of the cover body, and the engaging step portion The stepped wall surface is opposed to the side surface of the annular plate portion. 12. The swivel joint according to claim 10, characterized in that a retaining step capable of accommodating the outer peripheral portion of the retaining protrusion is provided on the inner edge of the upper surface of the cover, and the stepped wall of the retaining step is in contact with the outer periphery of the retaining protrusion. The sides of the holding protrusions are opposite to each other. 13. The swivel joint according to claim 10, wherein the annular plate portion has a cam portion that is detachably engaged with the locking portion and that protrudes below the rotary shaft direction.

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