JPH0654922U - Torque limiter - Google Patents

Abstract

(57) [Summary] [Purpose] The outer diameter can be reduced and the lack of transmission torque can be compensated. [Structure] In a torque limiter having the following basic structure, rollers 15 are provided in double rows L1 and L2. In the basic structure, the inner ring 14 is provided inside the outer ring 11 having the inclined surface 12 on the inner peripheral surface, and the roller 15 and the spring 17 are incorporated. The roller 15 is held by the cage 13 and the inclined surface 1 of the outer ring 11 is held.
Installed between 2 and inner ring 14. The spring 17 presses the roller 15 in the direction of narrowing the space between the inclined surface 12 and the inner ring 14, and the spring holding surface 18 provided on the outer ring 11
Engage with.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention is a torque limiter that transmits and cuts off rotational torque, and more specifically, a tension brake of a tape feeding mechanism of a magnetic recording device, a paper double feeding prevention mechanism in a paper feeding roller of an OA device, tape, ribbon, and sheet. The present invention relates to a torque limiter that can be used as a tension brake of a feed mechanism such as.

[0002]

[Prior art]

 As the torque limiter, a powder torque limiter and a spring clutch type torque limiter are generally known. However, the former torque limiter has a high price, and the latter torque limiter has a drawback that there is a large variation in torque. Japanese Patent Application No. 1-61430 proposes a torque limiter that eliminates such drawbacks by utilizing the basic structure of a one-way clutch, which is inexpensive in manufacturing cost and can provide stable on / off torque.

The above torque limiter is shown in FIGS. 3 to 5. That is, the inclined surfaces 12 are provided at a plurality of positions on the inner peripheral surface of the outer ring 11, and the cage 13 and the inner ring 14 are inserted into the outer ring 11. Rollers 15 interposed between the inclined surfaces 12 and the inner ring 14 are housed in the pockets 13 and incorporated in the cage 13. Each roller 15 is provided with a spring 17 for pressing in the direction in which the space between the inclined surface 12 and the inner ring 14 is narrowed, and is engaged with a holding surface 18 formed on the outer ring 11. It should be noted that one end of the outer ring 11 is closed by a pressing lid 19 that is fitted onto the inner ring 14, and an outer resin component 20 that covers the outer periphery of the pressing lid 19 and the other end of the outer ring 11 is provided on the outer periphery of the outer ring 11. Fixed. The inner ring 14 is connected by a pin 22 so as to rotate integrally with the inserted shaft 21.

In the basic structure as described above, when the shaft 21 normally rotates in the direction of arrow A in FIG. 3, the rotation is transmitted to the outer ring 11 via the rollers 15, and conversely, in the direction of arrow B in FIG. When the shaft rotates, the shaft 21 idles and the rotation transmission to the outer ring 11 is cut off, and the function as a one-way clutch is generated. By using the basic structure described above and adjusting the wedge angle of the inclined surface 12 and the spring force of the spring 17, it is possible to set the on / off torque for the rotation of the shaft 21 in the direction of the arrow B, and as a result, It is possible to configure a one-wait limiter with a reverse rotation prevention function that can set the idling torque.

[0005]

[Problems to be solved by the device]

 In office machines, there is a strong demand for a torque limiter with a small diameter. However, in order to change the design of the conventional torque limiter shown in FIG. 3 in response to the demand for a smaller diameter, if the same size as the current one is used for the roller 15 and the spring 17, the diameter of the inner ring 14 becomes smaller. The number of rollers 15 will decrease. However, when the inner ring diameter becomes smaller and the number of rollers becomes smaller in this way, the transmission torque becomes smaller. Further, if the size of the rollers 15 and the springs 17 is reduced without changing the diameter of the inner ring 14, the number of rollers 15 increases, but the spring force decreases, and as a result, the transmission torque also decreases. Moreover, the number of assembling steps increases and the assembling cost also increases.

An object of the present invention is to provide a torque limiter capable of reducing the outer diameter of the outer ring and compensating for the insufficient transmission torque.

[0007]

[Means for Solving the Problems]

 The torque limiter of the present invention is a torque limiter of the following basic structure, in which the rollers are provided in double rows in the axial direction of the inner ring. In the basic structure, an inner ring is provided in the inner portion of an outer ring having an inclined surface that is inclined with respect to the tangential direction on the inner peripheral surface, and a roller is incorporated between the inclined surface of the outer ring and the inner ring. A spring is provided that presses in the direction of narrowing the space between the surface and the inner ring. This spring is engaged with a spring holding surface provided on the outer ring.

[0008]

When the inner ring is rotated in the opening direction of the inclined surface of the outer ring, the rotation of the inner ring is transmitted to the outer ring through the rotation of the rollers pressed by the biasing force of the spring. Therefore, torque exceeding the torque corresponding to the maximum frictional force between the rollers and the inner and outer races generated by the pressing force of the spring is not transmitted, and idling occurs. Therefore, it functions as a torque limiter. In this case, since the rollers are provided in multiple rows, the number of rollers for one row is small, or the total number of rollers is large even if the pressing force of each spring is weak, so that a large torque can be transmitted. Become. Therefore, it is possible to make up for the shortage of transmission torque due to the reduction of the overall outer diameter.

[0009]

【Example】

 An embodiment of this invention will be described with reference to FIGS. As shown in the figure, the basic structure of the torque limiter is the same as that of the conventional example shown in FIG. The cage 13 and the inner ring 14 are inserted into the inside of the. Rollers 15 interposed between each inclined surface 12 and the inner ring 14 are housed and assembled in the cage 13 in the pocket 16. A spring holding surface 18 is further provided on the outer ring 11, and a spring 17 for pressing the roller 15 in the direction of narrowing the space between the inclined surface 12 and the inner ring 14 is engaged. As the spring 17, a leaf spring bent in an S shape is used.

The rows L1 and L2 of the torque limiter section having such a basic configuration are provided in multiple rows as shown in FIG. 1B. The rollers 15 in both rows L1 and L2 are out of phase with each other as shown in FIG. The outer ring 11 and the inner ring 14 of both rows L1 and L2 are each made of an integral part, and the inclined surface 12 and the spring holding surface 18 of the outer ring 11 in each row L1 and L2 are formed so as to be displaced from each other according to the arrangement of the rollers 15. There is. The retainer 13 is provided separately for each row L1, L2. Each cage 13 has a comb-like shape in which each pocket 16 is open toward the center of the outer ring 11.

It should be noted that both ends of the outer ring 11 are closed by a presser lid 19 which is fitted onto the inner ring 14, and an outer resin part 20 covering the outer periphery of the outer cover 11 and the other end of the outer ring 11 is provided on the outer periphery of the outer ring 11. Is fixed. The inner ring 14 is joined to the pin 22 of the shaft 21 by a notch so as to rotate integrally with the inserted shaft 21.

In the above structure, by adjusting the wedge angle of the inclined surface 12 and the spring force of the spring 17, the rotation of the shaft 21 in the direction of arrow A causes the roller 15 to move into the wedge space between the inclined surface 12 and the inner ring 14. It will bite and rotation will be blocked. The rotation of the shaft 21 in the direction of the arrow B is transmitted to the outer ring through the rotation of the roller 15 pressed against the inner ring 14 and the outer ring 11 by the spring 17. The torque transmitted through the rollers 15 is limited by the maximum frictional force or the like corresponding to the pressing force of the spring 17, and the shaft 21 will idle even if a torque larger than that is applied. Therefore, this torque limiter functions as a one-way torque limiter with a reverse rotation prevention function.

More specifically, the transmission torque of the rotation in the direction of arrow B is the pressing force of the spring 17, the friction coefficient of the roller 15 with respect to the inner and outer rings 14 and 11, the outer diameters of the roller 15 and the inner ring 14, the number of rollers 15, etc. Limited by Therefore, if the outer diameter of the inner ring 14 is reduced or the number of rollers 15 is reduced in order to reduce the overall outer diameter, the transmission torque is reduced. Further, even if the spring 17 has a small size, the transmission torque becomes small.

However, in this torque limiter, since the rollers 15 are arranged in multiple rows, even if the outer diameter of the inner ring 14 is reduced to reduce the number of rollers in each row L1 and L2, The number can be increased. Further, by reducing the number of rollers 15 in each row, it is not necessary to change the rollers 15 and the springs 17 to have a small size. Therefore, it is possible to compensate for the shortage of the transmission torque while satisfying the demand for a smaller outer diameter.

Although the arrangement phase of the rollers 15 in both rows L1 and L2 is different in the above-mentioned embodiment, they may be arranged in the same phase. In that case, the inclined surface 12 and the spring holding surface 18 of the outer ring 11 may be formed continuously over both rows L1 and L2. Further, in this torque limiter, the number of rollers 15 in each row L1 and L2 can be freely set.

[0016]

[Effect of device]

 The torque limiter of the present invention is a torque limiter of a type in which torque is transmitted between the inner and outer rings via rollers that are spring-biased to the inclined surface of the outer ring, and since the rollers are provided in double rows, Even if the diameter is reduced, it is possible to make up for the lack of transmission torque.

[Brief description of drawings]

FIG. 1A is a cross-sectional front view of a torque limiter according to the present invention, and FIG. 1B is a vertical cross-sectional side view of the same.

FIG. 2 is a perspective view showing a positional relationship between inner rings of the torque limiter.

FIG. 3 is a cross-sectional front view showing a conventional torque limiter.

FIG. 4 is a vertical sectional side view thereof.

FIG. 5 is a cutaway perspective view of the torque limiter.

[Explanation of symbols]

11 ... Outer ring, 12 ... Inclined surface, 13 ... Retainer, 14 ... Inner ring, 15 ... Roller, 17 ... Spring, 18 ... Spring holding surface, L
1, L2 ... Each row Row of torque limiter

Claims (1)

[Scope of utility model registration request] 1. An inner ring is provided inside an outer ring having an inner peripheral surface having an inclined surface inclined with respect to a tangential direction, and a roller is incorporated between the inclined surface of the outer ring and the inner ring. Provide a spring that presses in the direction of narrowing the space between the inner ring and
A torque limiter in which a holding surface for locking the spring is provided on the outer ring, wherein the rollers are provided in double rows in the axial direction of the inner ring.