JPH086792B2 - Rotation transmission device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention transmits rotation torque from an input shaft side to an output shaft side and prevents rotation torque transmission from the output shaft side to the input shaft side. It relates to the device.

[Conventional technology]

When the driven device rotates due to inertial force etc. even after the drive source such as a motor is stopped, and the rotation of the drive shaft of the drive source due to this rotational torque is not desirable, the output shaft is placed between the drive source and the driven device. A rotation transmission device that prevents the transmission of the rotation torque from the side to the input shaft side is used.

12 and 13 are cross-sectional views of a conventional rotation transmission device used for the above purpose. FIG. 12 shows a case where no rotation torque is transmitted from a drive source (not shown), and FIG. It is a figure which shows the case where the said rotational torque is transmitted. In the figure, (11) is an input shaft, (12) is an output shaft, (13) is a coil spring for pressing the flange portion of the input shaft (11) against the brake plate (15), and (16) is an input in the rotational direction. A key that connects the shaft (11) and the output shaft (12).

Next, the operation will be described. When torque is transmitted from the input shaft (11) side to the output shaft (12) side, from the state shown in FIG. 12, that is, the state where the flange portion of the input shaft (11) and the brake plate (15) are in contact, As shown in Fig. 13, push the input shaft (11) toward the output shaft (12) side, separate the flange of the input shaft (11) from the brake plate (15), and then apply rotational torque to the input shaft (11). . Rotating torque is key (16)
Is transmitted to the output shaft (12) via. When the back torque is applied from the output shaft (12) side to the input shaft (11) side when there is no transmission of the rotational torque from the input shaft (11), that is, in the state shown in FIG. 12, the input shaft (11) Since the flange part of is pressed against the brake plate (15) by the coil spring (13), a reaction torque due to friction works and neither the input shaft (11) nor the output shaft (12) rotates.

[Problems to be Solved by the Invention]

In the conventional rotation transmission device, when trying to transmit the rotation torque from the input shaft (11) side to the output shaft (12) side, the input shaft (11) must always resist the reaction force of the coil spring (13). There is a problem that it is necessary to push it toward the output shaft (12) side and separate the flange portion of the input shaft (11) from the brake plate (15). The present invention solves such a problem. A rotation transmission device capable of transmitting the rotation torque from the input shaft to the output shaft and preventing the transmission of the rotation torque from the output shaft side to the input shaft side even if the input shaft is not axially moved. Aim to get.

[Means for solving the problem]

A rotation transmission device according to the present invention has a coil spring press-fitted in a tubular portion of a housing and first and second groove portions into which the respective claw portions at both ends of the coil spring are fitted, respectively. And a first shaft that engages with the coil spring via a second groove portion, and first and second openings into which the claw portions at both ends of the coil spring are fitted, respectively. And a second shaft engaging with the coil spring through a second opening, and rotating the first shaft in a direction opposite to a winding direction of the coil spring,
When the groove portion of one of the two end claw portions locks one of the two
The first and second groove portions are provided so that the groove portion does not lock the other of the both end claw portions, and the second shaft is rotated in the same direction as the winding direction of the coil spring.
The first and second openings are provided so that the second opening does not lock the other of the both end claws when the opening of one of the both ends claws locks. .

[Operation] In the rotation transmission device configured as described above, when the first shaft rotates, the groove portion of the first shaft pushes one of the claw portions at both ends of the coil spring to wind the coil spring, The diameter of the spring is reduced to eliminate the pressure contact force between the coil spring and the cylindrical portion of the housing, and the rotational torque of the first shaft is transmitted to the second shaft via the claw of the coil spring. On the contrary, when the second shaft rotates, the opening of the second shaft pushes one of the claws at both ends of the coil spring to increase the diameter of the coil spring, thereby making the coil spring and the tubular part of the housing separate. The pressure contact force is increased, and rotation of the second shaft is prevented via the pressed claw portion.

Example of Invention

An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a view showing a cross section of a rotation transmission device of this embodiment, and FIG. 2 is an exploded perspective view of the device shown in FIG. In the figure, (1) is the first and second groove portions (1a), (1b) having a predetermined width in the circumferential direction on the circumferential portion thereof.
An input shaft serving as a second shaft, in which (2) is formed with a cylindrical portion (2c) and has a predetermined width in the circumferential direction, a first opening portion (2a), (2b) is formed on the output shaft as the first shaft, and (3) is a claw (3
Coil springs having a) and (3b), (4) is a cylindrical part (4
It is a housing with a). The input shaft (1) is inserted into the cylindrical portion (2c) of the output shaft (2), and the coil spring (3)
Are arranged on the outer periphery of the output shaft (2). At the positions of the claws (3a) and (3b) on both ends of this coil spring (3),
The first and second groove portions (1a) and (1b) of the input shaft and the first and second opening portions (2a) and (2b) of the output shaft overlap each other by a predetermined width, and the coil is formed in this portion. The claw portions (3a) (3b) of the spring (3) are engaged with each other. The non-overlapping portions of the first groove portion (1a) and the opening portion (2a) and the second groove portion (1b) and the opening portion (2b) are circumferential at the engaging portions of the claw portions (3a) (3b). The positional relationship in the direction is different, and the positional relationship is completely opposite. A component including the input shaft (1), the output shaft (2), and the coil spring (3) is inserted into the cylindrical portion (4a) of the housing (4).

The outer shape of the coil spring (3) is formed to be slightly larger than the inner diameter of the inner tubular portion (4a) of the housing (4), and when inserted into the inner tubular portion (4a) of the housing (4),
The output shaft (2) does not easily rotate due to the frictional force with the inner wall of the inner cylindrical portion (4a) of the outer peripheral housing (4) of the coil spring (3).

Next, the operating principle will be described with reference to FIG. FIG. 3 is a view showing a cross section perpendicular to the axis in a state where the coil spring (3) is inserted in the inner cylindrical portion (4a) of the housing (4). When a force is applied to the front claw (3a) in the direction of the arrow, that is, in the counterclockwise direction (hereinafter referred to as CCW direction), the outer circumference of the coil spring (3) and the inner cylinder of the housing (4) As described above, the frictional force due to the tension of the coil spring (3) exists between (4a), but the claw portion (3a)
By exerting a force on the coil spring (3), a force that presses the outer circumference of the coil spring (3) against the inner wall of the inner cylindrical portion (4a) of the housing (4) acts, and the frictional force between them increases, and The rotation of is completely restrained. Conversely, if a force is applied to the front claw (3a) from the direction opposite to the arrow shown in FIG. 3, that is, in the clockwise direction (hereinafter referred to as the CW direction), the coil spring (3) The outer diameter of the first thread is reduced as it is caught. The force to wind the coil spring (3) is the second
The coil spring (3) has a taper outer diameter as a whole, as a result of the propagating action of the streak and the third streak. As a result, the contact between the outer periphery of the coil spring (3) and the inner wall of the inner cylindrical portion (4a) of the housing (4) is limited to the portion near the other claw portion (3b), and the frictional force is significantly reduced. The coil spring (3) can rotate inside the cylindrical portion (4a) of the housing (4).

The above results are obtained not only with respect to the front side claw portion (3a) but also with the case where a force is applied to the rear side claw portion (3b). However, the direction of action of the force on the claw (3b) and the resulting phenomenon when observed from the front side are, of course, completely different from the case of the claw (3b) due to the relationship of the winding direction of the coil spring (3). It will be in the opposite direction.

Next, the operation of the rotation transmission device shown in FIG. 1 will be described. 4 and 5 are A- in FIG. 1 when the input shaft (1) is rotated in the CW direction.
It is a figure which shows the A and BB cross section. In Figure 4,
When the input shaft (1) is rotated in the CW direction, the input shaft (1)
The coil spring (3) is formed by pushing the claw (3a) with which the end (Xa) of the groove (1a) of this is engaged with this portion in the arrow direction.
, The outer diameter of the coil spring (3) becomes smaller, and the frictional force with the inner cylindrical portion (4a) of the housing (4) on the outer periphery of the coil spring (3) is reduced to allow the coil spring (3) to rotate together with the input shaft (1). The other claw (3b) of the coil spring (3) is, as shown in FIG. 5, the end (Xc) of the groove (1b) of the input shaft (1) or the opening (2b) of the output shaft (2). The coil spring (3) can be wound by being held in a state where it does not come into contact with the end (Yc) of the output shaft (2), and the end (Yb) of the opening (2a) of the output shaft (2) is connected to the coil spring (3). It is pushed by the end (Xa) of the groove (1a) of the input shaft (1) via the claw (3a) of 3) and rotates in the CW direction. As a result, the CW rotation torque of the input shaft (1) is It is transmitted to the output shaft (2) side.

6 and 7 are A-A and B- in FIG. 1 when the input shaft (1) is rotated in the CCW direction, respectively.
It is a figure which shows B cross section. In this case, in FIG. 7, the end (X) of the groove (1b) in the BB cross section of the input shaft (1)
d) engages with the claw portion (3b) and pushes this in the direction of the arrow to wind up the coil spring (3), that is, the other claw portion (3a), as shown in FIG. ) Is held so as not to contact the end (Xb) of the groove (1a) or the end (Yb) of the opening (2a) of the output shaft (2),
The coil spring (3) can be wound, and the output shaft (2) has the end (Yc) of the opening (2b) through the claw (3b) of the coil spring (3) on the input shaft (1). Groove (1b)
It is pushed by the end (Xd) of the shaft and rotates in the CCW direction. As a result, the CCW direction rotating torque of the input shaft (1) is output shaft (2).
Transmitted to the side.

8 and 9 show the output shaft (2) rotated in the CCW direction, and Figs. 10 and 11 show the output shaft (2) CW.
A- in Fig. 1 when rotated in the direction
It is a figure which shows the A and BB cross section.

When trying to rotate the output shaft (2) in the CCW direction, in FIG. 8, the first opening (2
The end (Yb) of (a) hits the claw (3a) of the coil spring (3), and a force is applied to the claw (3a) in the direction of expanding the coil spring (3), and the outer circumference of the coil spring and the housing (4). The frictional force between the cylindrical parts (4a) is increased to prevent the coil spring (3) from rotating. As a result, neither the input shaft (1) nor the output shaft (2) rotates in the CCW direction.

When the output shaft (2) is to be rotated in the CW direction, the end (Yc) of the second opening (2b) of the output shaft (2) is the coil spring (3) in FIG. ), The force is applied to the claw (3b) in the direction of expanding the coil spring (3), and for the same reason as when the output shaft (2) is rotated in the CCW direction. Neither the input shaft (1) nor the output shaft (2) rotate in the CW direction.

That is, the rotation from the output shaft (2) to the input shaft (1) side is not transmitted in both CW and CCW directions.

As described above, the reason why both the CW direction rotation and the CCW direction rotation of the input shaft (1) can be transmitted to the output shaft (2) side is that the outer diameter can be reduced by winding the coil spring (3). However, when one claw, for example (3a), is engaged with the end (Xa) of the groove (1a) of the input shaft (1) and the coil spring (3) is wound, the other claw (3a)
It is necessary that the groove width (1b) of the input shaft (1) engaged with b) and the opening width (3b) of the output shaft have a sufficient width B in the circumferential direction.

Actually, the rotation of the input shaft (1) is transmitted to the output shaft (2) in both the CW and CCW directions, and the rotation of the output shaft (2) to the input shaft (1) is transmitted in the CW and CCW directions. You must stop. To achieve this object, the circumferential widths of the first and second groove portions (1a), (1b) and the first and second opening portions (2a), (2b) are set to B,
Let C (the thickness of the spring) be the width of the overlapping portion of the first groove (1a) and the opening (2a) and the second groove (1b) and the opening (2b) in the circumferential direction. The width of the non-overlapping portion is BC, but the width of this non-overlapping portion BC
The claw part (3) when the coil spring (3) is rolled up.
It is formed larger than the relative deviation width A of a) and (3b).

Further, the positional relationship of the non-overlapping portions is formed as shown in FIGS. 4 to 11. That is,
The non-overlapping portions are formed in different circumferential directions at the engaging portions with the claw portions (3a) and (3b) at both ends of the coil spring (3).

For example, when the input shaft (1) is rotated in the CW direction, the end portion (Xc) of the second groove portion (1b) of the input shaft (1) in FIG. Before contacting 3b), the end (Xa) of the first groove (1a) contacts the claw (3a) in FIG. 4 so that the coil spring (3) is wound. Similarly, when the input shaft (1) is rotated in the CCW direction, in FIG. 6, the end (Xb) of the first groove (1a) of the input shaft (1) is the claw of the coil spring (3). Before contacting the portion (3a), in FIG. 7, the end (Xd) of the second groove (1b) contacts the claw (3b) so that the coil spring (3) is wound. First, the positional relationship between the first and second groove portions (1a) and (1b) of the input shaft (1) is determined.

First and second groove portions (1a), (1b) of the input shaft (1)
And the first and second openings (2a) of the output shaft (2),
As a result of the positional relationship of (2b) formed as above, when the output shaft (2) is attempted to rotate, the coil spring (3) acts in both CCW and CW directions to rewind the input. As a result, both the shaft (1) and the output shaft (2) are constrained. If the positions of the non-overlapping portions of the first groove (1a) and the opening (1b) and the second groove (1b) and the opening (2b) are opposite to the above, The rotation torque from the output shaft (2) side as the first shaft is transmitted, and the rotation torque from the input shaft (1) side as the second shaft is blocked. That is, in this case, the first shaft formed with the openings (2a) and (2b) is the input shaft,
The second shaft in which the groove is formed is used as the output shaft, and the same effect as above can be obtained.

In addition, the positional relationship between the first groove (1a) and the opening (2a) and the second groove (1b) and the opening (2b) is the same as that shown in FIGS. 4 to 11. When the winding direction of the coil spring (3) is different from that in the case, the transmission and blocking directions of the rotational torque are also opposite. In this case, the rotation transmission device using the first shaft as the input shaft and the second shaft as the output shaft. Is obtained.

〔The invention's effect〕

As described above, according to the present invention, when the first shaft rotates, the groove portion of the first shaft pushes the claw portion to either one of both ends of the coil spring, and the claw portion of the pressed coil spring is interposed. Transmits the rotational torque of the first shaft to the second shaft, and
When the second shaft rotates, the opening of the second shaft pushes one of the claws at both ends of the coil spring, and the rotation of the second shaft is blocked via the claw of the coil spring thus pressed. Therefore, the rotational torque is transmitted from the first shaft to the second shaft and the rotational torque is not transmitted from the second shaft to the first shaft without adding a special transmission component, which is economical and easy to use. A good input rotation transmission device can be obtained.

[Brief description of drawings]

1 is a sectional view showing a rotation transmission device according to an embodiment of the present invention, FIG. 2 is an exploded perspective view of the device shown in FIG. 1, and FIG. 3 is a coil with a coil spring inserted in a housing. Explanatory drawing showing the action of the spring, FIGS. 4 to 11 are views showing the AA cross section or the BB cross section of FIG.
Figures 4 and 5 are explanatory diagrams of the case where a rotational torque in the CW direction is applied to the input shaft, and Figures 6 and 7 are CCWs for the input shaft.
Fig.8 and Fig.9 are explanatory views when rotational torque in the CCW direction is applied to the output shaft, and Fig.10 and Fig.11 are CW direction in the output shaft. FIGS. 12 and 13 are sectional views showing a conventional rotation transmission device when a rotation torque is applied. In the figure, (1) is an input shaft, (1a) and (1b) are first and second groove portions, (2) is an output shaft, and (2a) and (2b) are first.
And a second opening, (3c) is a cylindrical part, (3) is a coil spring, (3a) and (3b) are claw parts of the coil spring, (4) is a housing, and (4a) is an inner cylinder part of the housing. Indicates. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A coil spring press-fitted into a tubular portion of a housing, and first and second groove portions into which respective claw portions at both ends of the coil spring are fitted, respectively.
A first shaft that engages with the coil spring through the groove of
A second shaft having first and second openings into which the respective claw portions at both ends of the coil spring are fitted, and a second shaft engaging with the coil spring through the first and second openings; ,
And rotating the first shaft in a direction opposite to the winding direction of the coil spring, and when the first groove portion locks one of the both end claw portions, the second groove portion has the both end claw portions. The first and second groove portions are provided so as not to lock the other, and the second shaft is rotated in the same direction as the winding direction of the coil spring so that the first opening portion has the both-end claw portions. The rotation transmitting device, wherein the first opening and the second opening are provided so that the second opening does not lock the other of the both-end claws when one of them is locked.