JP3282862B2 - Rotating connector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary connector for electrically or optically connecting members rotating within a relatively fixed range.

[0002]

2. Description of the Related Art A rotary connector that electrically or optically connects members rotating within a predetermined range, such as a vehicle steering wheel and a robot arm, and transmits an electric signal, a power signal, an optical signal, or the like is known. Have been. The rotating connector is rotatably assembled to each other, and has one end fixed to the first housing and the other end fixed to the second housing, respectively, in annular spaces formed in the first and second housings. In the annular space of the first and second housings, a flexible band-shaped transmission line called a flat cable is spirally wound and accommodated loosely, and the band-shaped transmission line is tightly wound or loosened. The first and second housings are allowed to rotate relative to each other. put it here,
The strip-shaped transmission line has a flexible transmission body such as a plurality of electric conductors arranged in parallel and a plurality of optical fibers coated in an electrically insulating material or a tape fiber covered with a plurality of optical fibers arranged in parallel. It is.

[0003] Compared to a connector device that connects members that rotate relative to each other by a brush or a slip ring, this rotary connector has no sliding contacts, so that noise is not included in a signal to be transmitted. It has been evaluated as a highly reliable connector device because it has advantages such as no circuit disconnection, and it has been evaluated as a highly reliable connector device. There is known a rotary connector in which an intermediate portion of a flat cable is wound in a reverse direction, and the housing is rotated in the reverse direction and moves in the space to allow relative rotation between the two housings.

[0004]

In the above-mentioned rotary connector, the relative rotation of the two housings is allowed by the tight tightening or loosening of the flat cable.
The number of relative rotations is determined by the number of turns of the flat cable. If the number of rotations is to be increased, the number of turns of the flat cable must be increased to make the cable longer.

In particular, the annular space formed in both housings requires about twice the volume occupied by the flat cable, and the volume of this annular space is determined by the length, width and thickness of the flat cable. Therefore, if the number of circuits of the flat cable is increased in the rotating connector having the same number of rotations, the width of the cable increases accordingly,
There is a problem in that the housing of the rotary connector becomes large, and a large space is required when assembling the housing to a vehicle or the like. In addition, the annular space requires about twice the volume occupied by the flat cable, and the flat cable is loosely accommodated in the space, so that the operation of tightening and loosening of the flat cable in the rotating connector involves the following. There is a problem that unpleasant abnormal noise such as sliding noise is generated.

In the case of a spirally wound flat cable, the annular space formed in both housings is a space required for tight tightening and loosening.
In the case of a flat cable having a rewinding part that is unwound in the middle part in the opposite direction, the space where the rewinding part moves in the circumferential direction due to the relative rotation of the two housings is a dead space that has no other use. I have. In particular, when the flat cable is rewound, unless the radius of the rewound portion is equal to or larger than a predetermined value, excessive stress acts on the flat cable when the rewound portion moves in the circumferential direction with the operation of the rotary connector. In addition, there has been a problem that electric conductors, optical fibers, and the like arranged in a flat cable are disconnected in a short period of time, and the life is shortened.

The present invention has been made in view of the above points, and the space for accommodating a flexible transmission body can be made as small as possible, and the transmission body has a long life and is inexpensive. An object of the present invention is to provide a highly reliable rotary connector.

[0008]

Means for Solving the Problems In order to achieve the above object, the present inventors have intensively studied the structure of a rotary connector and a transmission body. As a result, a transmission body used for a rotary connector, for example, a flat cable or a flexible printed circuit (FPC) uses a plurality of electric conductors arranged in parallel. At this time, the electric conductor of the transmission body is made into one, and this single transmission body is wound in a plurality of spirals, and is wound back in the middle part in the opposite direction, and the wound back parts are arranged at substantially equal intervals in the circumferential direction. Then, it has been found that the height of the housing, that is, the height corresponding to the width direction of the transmission body can be reduced to the width of a single transmission body while maintaining the same number of rotations of the rotary connector. .

The present invention has been made in view of such a fact, and includes first and second housings rotatably assembled to each other and having an annular space formed therein, one end of which is attached to the first housing. A rotary connector having a flexible transmission body whose ends are respectively fixed to the second housing and are spirally wound and accommodated in the annular spaces of the first and second housings; The transmission body is one
A single flexible transmission body in which an electric conductor is covered with an insulator is wound in a plurality of spirals, each transmission body is wrapped in the opposite direction at an intermediate portion, and each unwound portion is wound. The configuration is such that they are arranged at substantially equal intervals in the circumferential direction.

[0010] Preferably, the first and second housings are provided with a plurality of connecting portions which are arranged evenly over the entire circumference and connect respective inner ends and outer ends of the plurality of transmission bodies to an external device. . Also preferably, in the plurality of transmission bodies wound spirally, an insulating member is arranged between the transmission bodies overlapping each other.

More preferably, inner ends and outer ends of the plurality of transmission bodies wound spirally are respectively connected to the first and second housings, and these inner ends and outer ends are collected. Provide multiple wires to connect to external devices. Preferably, in the transmission body, a plurality of single transmission bodies are collected, a slit is formed between adjacent single transmission bodies, and each single transmission body is spirally wound, respectively. The intermediate portion is rewound in the opposite direction, and the rewound portions are arranged at substantially equal intervals in the circumferential direction.

[0012]

[Function] The flexibility of one electric conductor covered with an insulator is improved.
When a plurality of single transmission bodies are spirally wound, and each transmission body is rewound in the opposite direction at the intermediate portion, and the rewound winding parts are arranged at substantially equal intervals in the circumferential direction, the radius required by each winding part is obtained. And a plurality of transmission bodies are accommodated in the rotary connector. At this time, before Symbol first and second housing, it arranged uniformly on the entire circumference, providing a plurality of connecting portions for connecting the inner and outer ends of each of the plurality of transmission members with an external device, the length When using transmission bodies of the same length, the rewinding portions are arranged at substantially equal intervals in the circumferential direction.

Further, when the plurality of transmission bodies wound spirally are disposed with an insulating member between the overlapping transmission bodies, the plurality of transmission bodies can be used in an uncovered state without coating an electric conductor or an optical fiber. . Further, the inner and outer ends of the plurality of transmission bodies wound spirally are respectively connected to the first and second housings, and these inner and outer ends are aggregated and connected to an external device. When a plurality of wirings are provided, the connection part with the external device is divided into two parts, the input side and the output side.
Location.

[0014] Further, in the transmission body, a plurality of single transmission bodies are assembled, a slit is formed between adjacent single transmission bodies, and each single transmission body is spirally wound. At the same time, if the configuration is such that the rewinding parts are wound in the middle part in the reverse direction and the unwound parts are arranged at substantially equal intervals in the circumferential direction, a plurality of transmission bodies can be integrated into one,
Parts management becomes easy.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the rotary connector according to the present invention will be described in detail with reference to FIG. The rotary connector 1 includes a base plate 2, a roll plate 3, an outer case 4, and six flat cables 5. Here, the base plate 2 and the outer case 4 correspond to a first housing on a fixed side, and the roll plate 3 corresponds to a second housing on a rotating side. Both are integrally molded products made of synthetic resin. The roll plate 3 is assembled so as to be sandwiched between the case 4 and the flat plate 5. Six flat cables 5 are spirally wound and accommodated in an annular flat space formed inside the roll plate 3.

The base plate 2 is a disk-shaped member having an opening 2a formed in the center. At three locations on the outer periphery, mounting flanges 2b for attaching to a fixing member (not shown) are projected at substantially equal intervals, and a connector socket 2c is provided. Is provided. The roll plate 3 is a disk-shaped member having an outer diameter slightly smaller than that of the base plate 2 and having an insertion hole 3a formed in the center thereof for inserting a rotating member (not shown), and a lower end near the insertion hole 3a. Six connection terminals 3b respectively connected to the inner end of the flat cable 5 are protruded upward, and a rectangular notch 3c formed in the insertion port 3a is integrally formed by engaging with the rotating member. To rotate. A connector socket 6 is attached to the roll plate 3 around these connection terminals 3b. Here, the connector socket 6 is a portion for connecting a lead wire for connecting the rotary connector 1 to an external device together with the connector socket 2c of the base plate 2.

The outer case 4 has an upper flange 4b formed radially inward at an upper portion of the outer cylindrical portion 4a, and mounting flanges at three locations corresponding to the mounting flange 2b of the base plate 2 on the outer circumference of the outer cylindrical portion 4a. 4c is provided.
Here, the mounting flanges 2b and 4c are provided with insertion holes 2d and 4d through which mounting bolts and the like are inserted when the rotary connector 1 is mounted on the fixing member.

The flat cable 5 is a single flexible electric transmission body in which one electric conductor is covered with an insulator, and the six flat cables 5 are spirally wound as shown in the figure. Each of the flat cables 5 is wrapped in the reverse direction at the intermediate portion, and the rewound portions T are arranged at substantially equal intervals in the circumferential direction. And each flat cable 5
The connection terminals 5a are attached to the outer ends in advance, and each connection terminal 5a is connected to the connector socket 2c.

The rotary connector 1 spirally winds each of the six flat cables 5 and has a winding section T
Are wound around the intermediate portion in the reverse direction so that they are arranged at substantially equal intervals in the circumferential direction, the inner end is connected to the connection terminal 3b of the roll plate 3, and the connection terminal 5a attached to the outer end is connected to the connector socket 2c of the base plate 2. , Each connected. The roll plates 3 are sandwiched between the base plate 2 and the outer case 4 by matching the mounting flanges 2b and 4c, and the six flat cables 5 are inserted into a flat annular space formed therein. It is housed and assembled, attached to the rotating member using the opening 2a and the insertion hole 3a, and is fixed to the fixing member by bolts inserted into the insertion holes 2d and 4d.

The rotary connector 1 configured as described above
Is because six flat cables 5 are spirally wound with the rewinding portions T arranged at substantially equal intervals in the circumferential direction,
When the roll plate 3 rotates with the rotation of the rotating member, the rewinding portion T of each flat cable 5 moves in the circumferential direction, and the relative rotation with respect to the base plate 2 and the outer case 4 becomes possible.

At this time, the six flat cables 5
Since the rewinding portions T are arranged at substantially equal intervals in the circumferential direction,
Each rewinding part T presses the respective flat cable 5 in the outer peripheral direction, and the rewinding part T can only move in the circumferential direction. Therefore, the relative rotation of the roll plate 3 with respect to the base plate 2 and the outer case 4 can be any auxiliary tool. It is carried out smoothly and stably without using any.

Further, since the flat cable 5 is a single transmission body in which one electric conductor is covered with an insulator, the same number of electric circuits as the flat cable in which six electric conductors are covered with the insulator are used. Despite the configuration, the height of the rotary connector 1 is set to the width of the flat cable 5, that is, approximately 1/6.
Can be reduced. Next, a second embodiment of the rotary connector according to the present invention will be described with reference to FIGS.

The rotary connector 10 includes the base plate 1
1, an inner case 12, an outer case 13, and six flat cables 14;
And a first housing in which the outer case 13 is on the fixed side,
The inner case 12 corresponds to a second housing on the rotating side, and the base plate 11 to the outer case 13 are integrally molded products made of synthetic resin, and the inner case 12 is sandwiched between the base plate 11 and the outer case 13. When assembled, an annular flat space is formed in which six flat cables 14 are spirally wound and housed.

The base plate 11 has an opening 11a at the center.
Are formed, and engaging recesses 11b are provided at substantially equal intervals at four locations on the outer periphery. The inner case 12 has an upper flange 12b extending radially outward at an upper portion of the inner cylindrical portion 12a.
Connection connectors 12c are provided at equal intervals at the locations. Here, the inner case 12 is, as shown in FIG.
Slits 12d are provided in the vicinity of the inner cylindrical portion 12a where the connection connectors 12c are provided, and V-shaped concave grooves 12e are formed in the vertical direction on the outer peripheral side of each slit 12d. The inner case 12 is the outer case 1 in FIG.
3 is shown in an assembled state.

The outer case 13 has an upper flange 13b formed radially inward on an upper portion of the outer cylindrical portion 13a.
The inner diameter of the upper flange 13b is set slightly larger than that of the upper flange 12b so that the inner flange 12 can rotate relative to the inner case 12. Also, on the outer periphery of the outer cylindrical portion 13a,
The connection connectors 13c are formed at equal intervals at six locations, and lock claws 13d that engage with the respective engagement recesses 11b provided on the base plate 11 are vertically provided below the outer cylindrical portion 13a. Here, as shown in FIG. 3, the outer case 13 is provided with a slit 13e at a portion corresponding to each connector 13c of the outer cylindrical portion 13a, and a V-shaped concave groove is formed on the inner peripheral side of each slit 13e. 13f is formed vertically. In addition, as shown in FIG.
Connection terminals 12f and 13g for connecting lead wires connected to external devices are provided in c and 13c.

The flat cable 14 is a single transmitter in which one electric conductor is covered with an insulator. As shown in FIG. 3, the six flat cables 14 are spirally wound and The cable 14 is unwound in the reverse direction at the intermediate portion, and the unwound portions T are arranged at substantially equal intervals in the circumferential direction. As shown in FIG. 3, each flat cable 14 uses a connector 12c provided at the inner end of the inner case 12, a connector 13c provided at the outer end of the outer case 13, and slits 12d and 13e, respectively. Connected.

In the rotary connector 10 of this embodiment, each of the six flat cables 14 is spirally wound, and the intermediate portions are inverted so that the rewinding portions T are arranged at substantially equal intervals in the circumferential direction. Rewind in the direction and connect the inner end to connector 1.
2c, and the outer end is connected to the connector 13c.
Then, the inner case 12 is sandwiched between the base plate 11 and the outer case 13, and each lock claw 13d is engaged with the corresponding engagement concave portion 11b, so that six lock claws 13d are formed in a flat annular space formed therein. The flat cable 14 is accommodated and assembled.

The rotary connector 10 configured as described above
Since the six flat cables 14 are spirally wound with the rewinding portions T arranged at substantially equal intervals in the circumferential direction, when the inner case 12 rotates with the rotation of the rotating member, each The rewinding portion T of the flat cable 14 moves in the circumferential direction, and the relative rotation with respect to the base plate 11 and the outer case 13 becomes possible.

At this time, the six flat cables 14
Since the rewinding portions T are arranged at substantially equal intervals in the circumferential direction, the rewinding portions T press the respective flat cables 14 in the outer circumferential direction, and the rewinding portions T can only move in the circumferential direction. The relative rotation of the inner case 12 with respect to the base plate 11 and the outer case 13 is performed smoothly and stably similarly to the above embodiment.

Here, when the inner case 12 rotates relative to the base plate 11 and the outer case 13 in the clockwise direction in FIG. When the inner case 12 is relatively loosened while moving and the inner case 12 is relatively rotated counterclockwise, the flat cables 14 are tightly wound while the rewinding portion T moves in the circumferential counterclockwise direction.

When the inner case 12 rotates more than a predetermined number of times of rotation based on the length of each flat cable 14, each rewinding portion T formed at the intermediate portion disappears, and each flat cable 14 12
Is wound clockwise or counterclockwise around the inner cylindrical portion 12a according to the relative rotation direction of the inner cylinder portion 12a. At this time, the inner case 12 relatively rotates counterclockwise, and the inner cylindrical portion 12a
When each flat cable 14 is wound to the limit, the flat cable 14 is bent at the slit 13e of the outer case 13 as shown in FIG. On the other hand, when the inner case 12 relatively rotates clockwise and each flat cable 14 starts to be wound around the inner cylindrical portion 12a, as shown in FIG.
The flat cable 14 is the slit 1 of the inner case 12
It bends at the portion of 2d, and similarly, it has a bending habit.

The flat cable 1 has such a bending habit.
In the case of No. 4, when the inner case 12 relatively rotates in the opposite direction and returns to the original state in which the rewinding portion T is formed in the intermediate portion, the following problem occurs. That is, if this bent habit occurs in, for example, the slit 12d of the inner case 12, as shown in FIG. 6, if there is no V-shaped concave groove 12e in the slit 12d, the coil is wound thereon. The other flat cable 14 to be stacked is pushed up and protruded, and the flat cable 14 wound around this portion is loosened, so that the movement of each rewinding portion T in the circumferential direction due to the relative rotation of the inner case 12 is hindered. Will be. This state corresponds to the slit 13e of the outer case 13.
Also occurs in the part.

However, if the V-shaped concave grooves 12e and 13f are formed in the slits 12d and 13e of the inner case 12 and the outer case 13, the bent habit portions are formed in the concave grooves 12e and 13f. And the bent portion does not push up and protrude the other flat cable 14 to be wound. As a result, inner case 1
The movement of each rewinding portion T in the circumferential direction due to the relative rotation of 2 is not hindered, and the relative rotation of the inner case 12 with respect to the base plate 11 and the outer case 13 is smooth,
And it is performed stably.

Here, when the number of required electric circuits is small, the rotating connector 10 includes three electric conductors 15 and three insulating tapes 16 which are not coated with insulation, as shown in FIG. May be alternately spirally wound, and may be wound back in the opposite direction at an intermediate portion, and the wound back portions T may be arranged at substantially equal intervals in the circumferential direction. At this time, the three insulating tapes 16 are used such that the rewinding portions T are arranged at substantially equal intervals in the circumferential direction for the purpose of smoothly moving each rewinding portion T along the circumferential direction. . Therefore, each electric conductor 15
It may be a single flat cable 14 in which one electric conductor is covered with an insulator.

As shown in FIG. 8, the rotary connector 10 has six wirings 18 and 19 made of printed wiring or bus bars formed on the upper flanges 12b and 13b of the inner case 12 and the outer case 13, respectively. You may. In this case, in the inner case 12, the six wires 18 on the upper flange 12b side have one ends 18a arranged at equal intervals on the inner peripheral side and the other ends 18b arranged collectively on the outer peripheral side. In the outer case 13, the upper flange 1
The six wires 19 on the 3b side have one ends 19a arranged at equal intervals on the outer peripheral side and the other ends 19b are arranged collectively on one side on the outer peripheral side.

The inner end of each flat cable 14 is connected to one end 18a of a wiring 18 and the outer end is connected to one end 19a of a wiring 19.
And the other ends 18b of the six wirings 18 gathered on the outer peripheral side of the inner case 12 and the other end 19b of the six wirings 19 gathered on the outer peripheral side of the outer case 13 collectively. Connect to the lead wire that connects to the device. With this configuration, the number of connection points with the external device is reduced to two, and in addition to the above-described effects, the rotary connector can be further reduced in size.

Further, the transmission body is formed by assembling a plurality of single cables 21 in which one electric conductor 21a is covered with an insulator 22 like a flat cable 20 shown in FIGS. Slit 2 between one cable 21
3 may be formed. This flat cable 20 is made up of electric conductors 21a at both ends of each cable 21.
Is exposed, and each single cable 21 is bent at a right angle along a valley broken line shown by a broken line in FIG. 9 so that each single cable 21 is apparently separated as shown in FIG. Then, as shown in FIG. 11, the flat cable 20 spirally winds these single cables 21 together, wraps the intermediate portion of each cable 21 in the opposite direction, and surrounds each of the rewound parts T. Are arranged at substantially equal intervals in the direction.

When the flat cable 20 is configured in this manner, a plurality of flat cables can be integrated into one, and component management becomes easy. In each of the above embodiments, if a flat cable is wound around using a high-viscosity oil or fat such as grease, a more stable relative rotation of the rotary connector can be realized. Also, the transmission body is 1
A case has been described where a single flexible electric conductor in which the electric conductor of the present invention is covered with an insulator is used. For example, a single optical fiber having a single optical fiber coated with a flexible optical fiber is described. It may be a transmission body, or a composite of an electric conductor and an optical fiber and covered with an insulator.

[0039]

As is apparent from the above description, according to the present invention, the space for accommodating the flexible transmission body can be made as small as possible and the transmission body can have a long life.
An inexpensive and highly reliable rotary connector is provided. Also,
When the first and second housings are provided evenly over the entire circumference and provided with a plurality of connecting portions for connecting respective inner ends and outer ends of the plurality of transmission bodies to an external device, the lengths are equal. When the transmission body is used, the rewinding portions are arranged at substantially equal intervals in the circumferential direction.

Further, when a plurality of transmission bodies wound spirally are arranged with an insulating member between the overlapping transmission bodies, the transmission bodies can be used in an uncovered state without coating an electric conductor or an optical fiber. . Further, the inner and outer ends of the plurality of transmission bodies wound spirally are respectively connected to the first and second housings, and these inner and outer ends are aggregated and connected to an external device. When a plurality of wirings are provided, the connection part with the external device is divided into two parts, the input side and the output side.
Location.

Further, in the transmission body, a plurality of single transmission bodies are assembled, a slit is formed between adjacent single transmission bodies, and each single transmission body is spirally wound. At the same time, if the configuration is such that the rewinding parts are wound in the middle part in the reverse direction and the unwound parts are arranged at substantially equal intervals in the circumferential direction, a plurality of transmission bodies can be integrated into one,
Parts management becomes easy.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an assembled state of a rotary connector according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view showing an assembled state of a rotary connector according to a second embodiment of the present invention without a flat cable.

FIG. 3 is a plan view showing a cross section of the rotary connector of FIG. 2;

FIG. 4 is a plan view showing a cross section of a main part in a state where the flat cable is bent on the outer case side in the rotary connector of FIG. 2;

FIG. 5 is a plan view showing a cross section of a main part of the rotary connector of FIG. 2 in a state where a flat cable is bent on an inner case side.

FIG. 6 is a plan view showing the behavior of the flat cable in a case where the slits of the inner case do not have a concave groove, with a main part in section.

FIG. 7 is a plan view showing a cross section of a modification of the rotary connector shown in FIG. 2;

FIG. 8 is a plan view showing a cross section of another modification of the rotary connector shown in FIG. 2;

FIG. 9 is a front view showing a modification of the flat cable used for the rotary connector of the present invention.

FIG. 10 is a perspective view showing a state where the flat cable shown in FIG. 9 is bent along a broken line.

11 is a plan view showing a state in which the flat cable of FIG. 10 is spirally wound and wrapped in the reverse direction at an intermediate portion, and the wrapped portions are arranged at substantially equal intervals in the circumferential direction.

[Explanation of symbols]

 Reference Signs List 1 rotating connector 2 base plate (first housing) 2c connector socket 3 roll plate (second housing) 4 outer case (first housing) 5 flat cable (single transmission body) 6 connector socket 10 rotating connector 11 base plate (First housing) 12 inner case (second housing) 13 outer case (first housing) 14 flat cable (single transmission body) 15 electric conductor 16 insulating tape 18, 19 wiring 20 flat cable 21 single Cable T rewind

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H01R 35/04 B60R 16/02

Claims (5)

(57) [Claims] 1. A first and a second housing rotatably assembled to each other and having an annular space formed therein, one end of which is fixed to the first housing and the other end of which is fixed to the second housing. A rotary connector having a flexible transmission body which is spirally wound and accommodated in an annular space of the first and second housings, wherein the transmission body has one electric conductor insulated. Flexible with body covering
A plurality of single transmission bodies are spirally wound around each other, and each transmission body is wrapped in the middle part in the opposite direction, and each rewound part is arranged at substantially equal intervals in the circumferential direction. Features a rotating connector. 2. A pre-Symbol first and second housing are arranged uniformly on the entire circumference, a plurality of connecting portions for connecting the inner and outer ends of each of the plurality of transmission members with an external device Yes,
The rotating connector according to claim 1. 3. The rotary connector according to claim 1, wherein the plurality of transmission bodies wound spirally have an insulating member disposed between the overlapping transmission bodies. 4. The first and second housings are connected to an inner end and an outer end of the plurality of transmission bodies wound spirally, respectively, and collect these inner ends and outer ends to form an external device. 2. A plurality of wirings for connecting to a plurality of wires are provided.
Rotating connector. 5. The transmission body includes a plurality of single transmission bodies, a slit formed between adjacent single transmission bodies, and each single transmission body spirally wound. 2. The rotary connector according to claim 1, wherein the intermediate portion is rewound in the opposite direction, and the rewound portions are arranged at substantially equal intervals in the circumferential direction.