JPH062587U - Transmission device between two relatively rotating members - Google Patents

Abstract

(57) [Summary] [Purpose] When rotating the inner case 2 in the direction of the arrow C to wind the flat cable 4 inside the outer case 3, the two members are relatively rotatable and do not become unrotatable. A transmission device is provided. [Structure] A spirally wound flat cable 4 having a winding direction reversing portion 5 is housed between a relatively rotatable inner case 2 and an outer case 3. The pressing body 6 was arranged in the space 10 between the cases 2 and 3. The pressing body 6 is 4
The auxiliary roll 7 and the endless belt 8 individually press the outer peripheral surface of the flat cable 4 wound around the inner case 2. The rotation force of the inner case 2 is surely flat cable 4
The flat cable 4 is transmitted to the reversing section 5 and does not become unrotatable.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a transmission device between two relatively rotating members used for transmitting electric signals, optical signals, etc. between the two relatively rotating members.

[0002]

[Prior art]

 As shown in FIGS. 5 to 7, in a conventional transmission device 1 between two relatively rotating members, an inner case 2 and an outer case 3 coaxially arranged are relatively rotatable, and In the space 10 formed by the inner case 2 and the outer case 3, a spirally wound flat cable 4 whose winding direction is reversed midway in the longitudinal direction is housed. In the figure, 5 is an inversion part of the flat cable 4. The inner end 4a of the flat cable 4 is fixed to the inner case 2, and the outer end 4b of the flat cable 4 is fixed to the outer case 3.

Next, the operation of this device will be described. When the inner case 2 is rotated and the outer case 3 is fixed, first, from the state shown in FIG. 5, when the inner case 2 is rotated in the direction of arrow A and the flat cable 4 is wound around the inner case 2. Will be explained. When the inner case 2 is rotated in the direction of arrow A, the reversing part 5 of the flat cable 4 moves in the direction of arrow B accordingly, and the flat cable 4 wound inside the outer case 3 is sequentially reversed. As it passes through, it is rolled up on the inner case 2 side. In this way, when the flat cable 4 is almost entirely wound around the inner case 2, the result is as shown in FIG.

Next, a case where the inner case 2 is rotated in the direction of arrow C from the state shown in FIG. 5 and the flat cable 4 is wound inside the outer case 3 will be described. When the inner case 2 is rotated in the direction of arrow C, the reversing portion 5 of the flat cable 4 is moved in the direction of arrow D accordingly, and the flat cables 4 wound on the inner case 2 are unwound in order and inverted. While passing through the portion 5, it is rolled up inside the outer case 3. In this way, when the flat cable 4 is almost entirely wound around the outer case 3, the result is as shown in FIG.

Since the transmission device having such a configuration has no sliding connection portion, it has an advantage that a highly reliable transmission line can be configured between two relatively rotating members. In addition, if the flat cable 4 with the winding direction reversed in the middle of the longitudinal direction is used, the length of the flat cable required to obtain the same relative rotation speed as compared with a flat cable wound in one direction in a spiral shape. There is an advantage that the length can be shortened.

[0006]

[Problems to be solved by the device]

 However, such a transmission device between two relatively rotating members does not cause any problem when the inner case 2 is rotated in the direction of arrow A, but the inner case 2 is rotated in the direction of arrow C to generate a flat cable. 4 is wound on the outer case 3 side, the flat cable 4 wound on the inner case 2 loosens and sticks out into the space 10 formed by the inner case 1 and the outer case 2, and finally, There is a problem that the protruding portion interferes with the reversing portion 5 and cannot rotate.

As a result of observing the above phenomenon in detail, the following facts were found. That is, in order to rotate the inner case 2 in the direction of the arrow C to unwind the flat cable 4 from the inner case 2 and wind the flat cable 4 onto the outer case 3, the rotational force of the inner case 2 must be ensured. It is necessary to inform the reversing unit 5. However, since the flat cable 4 has a structure in which a tape-shaped conductor is sandwiched between two plastic films, slippage is likely to occur between the adjacent flat cables 4 as inner and outer layers. Therefore, the rotational force of the inner case 2 is not transmitted to the reversing portion 5 of the flat cable 4, the reversing portion 5 becomes a fixed point, and the flat cable 4 between the reversing portion 5 and the inner case 2 causes winding looseness. Eventually, it becomes impossible to rotate.

Although the above example is the case where the inner case 2 is rotated, the same problem occurs when the inner case 2 is fixed and the outer case 3 is rotated.

[0009]

[The purpose of the device]

 The present invention has been made in view of the above problems, and becomes unrotatable when the inner case 2 is rotated in the direction in which the flat cable 4 is unwound and the flat cable 4 is wound inside the outer case 3. It is intended to provide a transmission device between two relatively rotating members without a problem.

[0010]

[Means for Solving the Problems]

 In order to achieve this object, the present invention has a structure in which an inner case and an outer case that are coaxially arranged are relatively rotatable, and a longitudinal direction is provided in a space formed by the inner case and the outer case. In a transmission device between two relatively rotating members, which accommodates a spirally wound flat cable whose winding direction is reversed in the middle of, a plurality of members are provided in the space formed by the inner case and the outer case. A pressing body having one auxiliary roll and an endless belt rotatably wound around the plurality of auxiliary rolls is arranged, and the flat cable wound around the inner case is pressed by the pressing body. It is what

[0011]

[Action]

 By pressing the flat cable wound on the inner case with the endless belt of the pressing body, the rotational force of the inner case 2 can be reliably transmitted to the reversing part of the flat cable 4, and the reversing part of the flat cable 4 moves. Will be certain. Therefore, when the flat cable 4 is wound in the unwinding direction to wind the flat cable 4 inside the outer case 3, the flat cable 4 does not become unrotatable.

[0012]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIGS. 1 to 3, the transmission device 1 between two relatively rotating members according to the present invention is configured such that an inner case 2 and an outer case 3 coaxially arranged are relatively rotatable. In the flat cable 4, the spiral wound flat cable 4 whose winding direction is reversed in the longitudinal direction is housed in the space formed by the inner case 2 and the outer case 3. The end 4a is fixed to the inner case 2 and the outer end 4b is fixed to the outer case 3 respectively, which is the same as the conventional one, but the feature of this device is that the inner case 2 and the outer case 4 are different. That is, the pressing body 6 is arranged in the formed space 10.

The pressing body 6 is composed of four auxiliary rolls 7 whose relative positions are fixed, and an endless belt 8 rotatably wound around the auxiliary rolls 7. The four auxiliary rolls 7 are supported by a carrier or the like (not shown) and can rotate independently of the inner case 2 and the outer case 3 around the axis of the transmission device in a state where their relative positions are fixed. Are arranged as follows. The endless belt 8 rotatably wound around the four auxiliary rolls 7 is arranged so that the outer circumference of the flat cable 4 wound around the inner case can be constantly pressed. For this reason, the four auxiliary rolls 7 are elastic materials (rubber material) rich in flexibility so that they can be deformed correspondingly even if the thickness of the flat cable 4 wound on the inner case 2 changes. Or foamed plastic). On the other hand, the endless belt 8 is also made of a stretchable elastic material so that it can cope with the deformation of the auxiliary roll 7.

Therefore, the endless belt 8 is in constant contact with the outer peripheral surface of the flat cable 4 wound around the inner case 2 while being pressed. In addition, it is preferable to apply a lubricant having an appropriate coefficient of friction to the surface of the endless belt 8 on the side in contact with the flat cable 4.

Next, the operation of this device will be described. First, a case where the inner case 2 is rotated in the direction of arrow A while the outer case 3 is fixed and the flat cable 4 is wound around the inner case 2 from the state of FIG. 1 will be described. When the inner case 2 is rotated in the direction of arrow A, the reversing portion 5 of the flat cable 4 moves in the direction of arrow B accordingly, and the flat cable 4 wound on the outer case 3 successively passes through the reversing portion 5. Meanwhile, it is wound up on the inner case 2. In this way, when the flat cable 4 is almost completely wound around the inner case 2, the result is as shown in FIG.

During this rotation, the reversing portion 5 of the flat cable 4 collides with or interferes with the pressing body 6, but the auxiliary roll 7 has the inner case 2 and the outer case 3 centered on the axis of the transmission device. Since the endless belt 8 is rotatably wound around the auxiliary roll 7, the pressing body 6 does not interfere with the rotation. Therefore, there is no particular problem when the inner case 2 is rotated in the direction of arrow A.

Next, a case where the inner case 2 is rotated in the direction of arrow C while the outer case 3 is fixed and the flat cable 4 is wound inside the outer case 3 from the state of FIG. 1 will be described. In the present invention, the endless belt 8 wound around the auxiliary roll 7 is in contact with the outer peripheral surface of the flat cable 4 while being pressed by the auxiliary roll 7. For this reason, the flat cable 4 wound around the inner case 2 passes through the reversing portion 5 sequentially without being loosened and is wound inside the outer case 3. At this time, the pressing body 6 does not hinder the rotation as in the above case. Therefore, no problem occurs when the inner case 2 is rotated in the direction of arrow C. In this way, when the flat cable 4 is almost completely wound around the outer case 3, the result is as shown in FIG.

Although the case where the inner case 2 is rotated has been described above, the case where the outer case 3 is rotated can be similarly smoothly rotated. In this case, it is preferable that the pressing body 6 presses the inner peripheral surface of the flat cable 4 wound inside the outer case 3. Further, the number of the auxiliary rolls 7 is not limited to four and may be three or five.

FIG. 4 shows another embodiment of the present invention, in which the auxiliary roll 7 of the pressing body 6 is moved by the planetary gear 11. That is, the planetary gear 11 is rotatably supported by the carrier 12, and is arranged so as to mesh with both the sun gear 13 and the internal gear 14 which are coaxially arranged. The sun gear 13 is fixed to the inner case 2, the internal gear 14 is fixed to the outer case 3, and the carrier 12 rotatably supports the auxiliary roll 7. The number of planetary gears 11 is not limited to one, and it is possible to install as many auxiliary rolls 7 as there are.

Generally, the reversing portion 5 of the flat cable 4 makes an orbital movement around the axis of the transmission device as the inner case 2 rotates, but the speed of the orbital movement is higher than that of the inner case 2. The speed is slow and becomes the same as the revolution speed of the planetary gears of the planetary gear mechanism. Therefore, by moving the plurality of auxiliary rolls 7 by the planetary gears 11, the plurality of auxiliary rolls 7 and the endless belt 8 stretched around the auxiliary rolls 7 are substantially synchronized with the revolving movement of the reversing portion 5 of the flat cable 4. Can be made.

However, the speed of the revolving movement of the inversion portion 5 of the flat cable changes depending on the winding state of the flat cable 4 around the inner case 2 and the outer case 3, but in the planetary gear mechanism, each gear used The rotation speed is set to a constant value depending on the pitch circle diameter. Therefore, it is preferable that the planetary gear mechanism used is set so that the revolution speed of the planetary gear becomes the average value of the orbital speed of the reversing portion 5 of the flat cable 4.

In the configuration using such a planetary gear mechanism, the flat cable 4 is extremely thin, and there is a possibility that the flat cable 4 may be damaged by collision or interference with the pressing body 6 that occurs during rotation. In this case, it is effective to prevent the collision and the interference, and to prevent the flat cable 4 from being damaged.

[0023]

[Effect of device]

 As described above, according to the present invention, the flat cable is pressed by the pressing body having the plurality of auxiliary rolls and the endless belt rotatably wound around the plurality of auxiliary rolls. The rotating force can be reliably transmitted to the reversing part of the, so that the trouble of the flat cable does not prevent the rotation. In addition, the pressing body does not hinder the rotation of the inner case or the outer case, and can smoothly rotate.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a transmission device according to an embodiment of the present invention.

FIG. 2 is a transverse cross-sectional view of the device of FIG. 1 in which the flat cable is wound around the inner case side.

FIG. 3 is a cross-sectional view of the device of FIG. 1 in a state where the flat cable is wound around the outer case side.

FIG. 4 is an explanatory view showing another embodiment of the present invention.

FIG. 5 is a cross-sectional view of a conventional transmission device.

FIG. 6 is a cross-sectional view of the device of FIG. 5 with the flat cable wound around the inner case side.

FIG. 7 is a cross-sectional view of the device of FIG. 5 with the flat cable wound around the outer case side.

[Explanation of symbols]

1: Transmission device 2: Inner case 3: Outer case 4:
Flat cable 5: Inversion part 6: Pressing body 7: Auxiliary roll 8: Endless belt 10: Space 11: Planetary gear 12: Carrier 13: Sun gear 1
4: Internal gear

Claims (1)

[Scope of utility model registration request] 1. An inner case and an outer case which are coaxially arranged are relatively rotatable, and a winding direction is midway in a longitudinal direction in a space formed by the inner case and the outer case. In a transmission device between two relatively rotating members that accommodates an inverted spiral wound flat cable, a plurality of auxiliary rolls and a plurality of auxiliary rolls are provided in a space formed by the inner case and the outer case. A pressing body having an endless belt rotatably wound around each auxiliary roll is arranged, and the flat cable wound around the inner case is pressed by the pressing body to rotate relatively. Transmission device between two members.