JP6046859B2 - Reverse input cutoff clutch - Google Patents

Description

  The present invention relates to a reverse input cutoff clutch in which bidirectional torque from the input side is transmitted to the output side, but torque from the output side is not transmitted to the input side.

  In the reverse input cutoff clutch, bidirectional driving force from the input side is transmitted to the output side, but rotational force from the output side is prevented from transmitting to the input side (see, for example, Patent Document 1). 3 is an explanatory view showing an example of a conventional reverse input cutoff clutch 11. FIG. 3 (a) is a configuration diagram, FIG. 3 (b) is a perspective view of the input shaft 12, and FIG. 3 (c) is an output shaft. 13 is a perspective view of FIG. In FIG. 3A, the upper half is shown in a sectional view.

  The reverse input shut-off clutch 11 transmits a bidirectional rotational force input to the input shaft 12 in the forward direction and the reverse direction to the output shaft 13, and the bidirectional rotational force from the input shaft 12 is applied to the output shaft. 13, but the rotational force from the output shaft 13 is not transmitted to the input shaft 12. The outer ring 14 stores a transmission mechanism for achieving this function, the input shaft 12 of the outer ring 14 is provided with a lid 15, and the side wall 16 is formed on the output shaft 13 side of the outer ring 14. Yes. The transmission mechanism includes an input member 12A that engages with the input shaft 12, an output member 13A that is provided on the output shaft 13, and a rolling member 17 that contacts the inner surface of the outer ring.

  As shown in FIG. 3B, the input shaft 12 is coupled to an input member 12A, and the input member 12A is provided with a plurality of input engagement portions 12B. As shown in FIG. 3C, the output shaft 13 has an output member 13A, and the output member 13A is provided with a plurality of output engaging portions 13B. The input shaft 12 and the output shaft 13 have a plurality of input engagement portions 12B and a plurality of output engagement portions 13B that are alternately fitted, and a flat portion of the input member 12A and a flat portion of the output member 13A are flat surfaces. Contact in contact. In the following description, a contact portion between the flat surface portion of the input member 12A and the flat surface portion of the output member 13A is referred to as a contact portion between the input shaft 12 and the output shaft 13.

  FIG. 4 is an operation explanatory diagram of the conventional reverse input cutoff clutch 11. FIG. 4A is an explanatory diagram of the positional relationship among the rolling member 17, the input engagement portion 12B, and the output engagement portion 13B in a stationary state in which no rotational force is applied to either the input shaft 12 or the output shaft 13. FIG. 4B is an explanatory diagram of the positional relationship between the rolling member 17, the input engagement portion 12B, and the output engagement portion 13B when a counterclockwise rotational force is applied to the output shaft 13. FIG. ) Is an explanatory diagram of the positional relationship of the rolling member 17, the input engagement portion 12B, and the output engagement portion 13B when a counterclockwise rotational force is applied to the input shaft 12.

  As shown in FIG. 4A, in a stationary state in which no rotational force is applied to either the input shaft 12 or the output shaft 13, the rolling member 17 is positioned substantially at the center of the output engagement portion 13B. Further, the rolling member 17 faces the output engagement portion 13B with a slight distance, and the rolling member 17 faces the inner wall surface 18 of the outer ring 14 with a slight gap.

  Now, assuming that a counterclockwise rotational force is applied to the output shaft 13 from the stationary state of FIG. 4A, as shown in FIG. 4B, the output engaging portion 13B has a rotational force in the direction of the left arrow. As a result, the output engagement portion 13B moves in the direction of the left arrow. Since the output engagement portion 13B operates freely and smoothly independently within a certain rotation range (interval between adjacent input engagement portions 12B), the input engagement portion 12B does not operate. Accordingly, as the output engagement portion 13B moves in the left arrow direction, the rolling member 17 is pushed upward by the output engagement portion 13B. As a result, the gap between the output engagement portion 13B and the inner wall surface 18 of the outer ring 14 is narrowed, and the rolling member 17 enters the locked state between the output engagement portion 13B and the inner wall surface 18 of the outer ring 14. In this way, the rotational force applied to the output shaft 13 is blocked and is not transmitted to the input shaft 12.

  On the other hand, if a counterclockwise rotational force is applied to the input shaft 12 from the stationary state of FIG. 4A, the input engagement portion 12B rotates in the direction of the left arrow as shown in FIG. 4C. First, the side surface of the input engagement portion 12B comes into contact with the side surface of the output engagement portion 13B or the side surface of the rolling member 17. Further, when the input engagement portion 12B rotates in the left arrow direction, the side surface of the input engagement portion 12B comes into contact with both the output engagement portion 13B and the side surface of the rolling member 17, and the input engagement portion 12B Without engaging the rolling member 17 between the output engaging portion 13B and the inner wall surface 18 of the outer ring 14, the output engaging portion 13B and the rolling member 17 are pushed in the left arrow direction. That is, if the input shaft 12 rotates counterclockwise, the output shaft 13 rotates together with the input shaft 12, and the rotational force applied to the input shaft 12 is transmitted to the output shaft 13. Even when the input shaft 12 rotates in the clockwise direction, only the direction is different, the input engagement portion 12B abuts on the output engagement portion 13B and the rolling member 17, and similarly, the output shaft 13 is the input shaft 12 The rotational force applied to the input shaft 12 is transmitted to the output shaft 13.

JP 2007-32634 A

  However, it has been found that there is a case where the rotational force applied to the output shaft 13 is not blocked by the repeated operation of the reverse input cutoff clutch. This is because an adhesive substance formed of oil such as grease and friction powder is generated, and the contact portion between the input shaft 12 and the output shaft 13 is in a state where the input engagement portion 12B and the output engagement portion 13B are in contact. Occurs when integrated by sticking. In particular, since the contact portion between the input shaft 12 and the output shaft 13 is in a flat surface contact state, in the case of a small reverse input cutoff clutch, the input shaft 12 and the output shaft 13 are caused by the adhesive substance. The abutting part is easily adhered and integrated. If the contact portion between the input shaft 12 and the output shaft 13 is integrated with the input engagement portion 12B and the output engagement portion 13B being in contact, the rotational force applied to the output shaft 13 cannot be blocked.

  FIG. 5 is an operation explanatory diagram when the contact portion between the input shaft 12 and the output shaft 13 is integrated and the rotational force of the output shaft 13 cannot be prevented. FIG. 5A is a diagram illustrating the operation of the input engagement portion 12B and the output engagement. Description of the positional relationship among the rolling member 17, the input engagement portion 12B, and the output engagement portion 13B when the contact portion between the input shaft 12 and the output shaft 13 is integrated with the joint portion 13B in contact 5B is a positional relationship among the rolling member 17, the input engagement portion 12B, and the output engagement portion 13B when a counterclockwise rotational force is applied to the output shaft 13 in the state of FIG. 5A. It is explanatory drawing of.

  Now, when the contact portion between the input shaft 12 and the output shaft 13 is integrated with the input engagement portion 12B and the output engagement portion 13B shown in FIG. If a counterclockwise rotational force is applied, the contact portion between the input shaft 12 and the output shaft 13 is integrated, so that the input engagement portion 12B is connected to the output engagement portion as shown in FIG. Since it rotates integrally with the joint portion 13B, as the output engagement portion 13B moves in the direction of the left arrow, the rolling member 17 also moves in the direction of the left arrow, and the operation is the same as in FIG. The rolling member 17 is not pushed upward by the output engagement portion 13B. Thus, when the contact part of the input shaft 12 and the output shaft 13 is integrated, the rotational force applied to the output shaft 13 cannot be prevented.

  The object of the present invention is to prevent reverse input blocking that can prevent the contact portion between the input shaft and the output shaft from sticking and being integrated even if an adhesive material is generated, and can block the rotational force applied to the output shaft. Is to provide a clutch.

In view of the above object, the present invention provides:
“An input shaft to which rotational force is input, an output shaft that outputs rotational force, and when the rotational force is applied to the input shaft, the output shaft is allowed to rotate and the rotational force is applied to the output shaft. A reverse input cut-off clutch comprising a transmission mechanism for preventing rotation of the shaft and an outer ring housing the transmission mechanism;
The input shaft and the output shaft are each formed with opposing flat portions, and the flat portions are housed in the outer ring together with oil such as grease,
One of the flat portions is formed with a protrusion that is continuous over the entire circumference around the central axis of the input shaft or the output shaft , and the tip of the protrusion is in contact with the other flat portion. ing"
The reverse input cutoff clutch is characterized by the above. Here, the cross section of the protrusion may be arcuate or trapezoidal .

In the reverse input shut-off clutch, as described above, the contact portion between the input shaft and the output shaft is in a flat surface contact state, and is easily integrated by an adhesive substance caused by the presence of oil such as grease. In the plane portion where the input shaft and the output shaft face each other, a projection portion that is continuous over the entire circumference around the central axis of the input shaft or the output shaft is formed on one plane portion. The tip of the abuts against the other flat portion. As a result, the contact area where the input shaft and the output shaft come into contact with each other is greatly reduced, and even if an adhesive substance is generated, the contact portion between the input shaft and the output shaft can be prevented from sticking and being integrated. .
In other words, the protrusion formed on the flat surface functions as an anti-adhesion part, and as a result, the output shaft can ensure free and smooth independent operation in a certain rotation range, so that the rotational force applied to the output shaft Can be reliably prevented. Further, the projection of the present invention is continuously formed around the central axis over the entire circumference, and since the tip of the projection abuts against the other flat surface over the entire circumference, the input shaft and the output shaft rotate. It is possible to prevent the situation where the operation becomes unstable due to a relative inclination inside .

Various explanatory view showing an example or the like of the reverse input blocking clutch according to the exemplary shaped state of the present invention. The explanatory view showing the reverse input interception clutch used as a reference example to the present invention. An explanatory view showing an example of the conventional reverse input interception clutch. Operation | movement explanatory drawing of the conventional reverse input interruption | blocking clutch. FIG. 6 is an operation explanatory diagram when the contact portion between the input shaft and the output shaft is integrated and the rotational force of the output shaft cannot be prevented.

Embodiments of the present invention will be described below. Figure 1 shows the flat surface portion facing and the anti-tack portion to form a protrusion over the entire circumference around the central axis, the reverse input blocking clutch according to the exemplary shaped state of the present invention various examples, etc. FIG. 1A is an overall view of a reverse input cutoff clutch according to an embodiment of the present invention (the upper half is shown in a sectional view), and FIGS. 1B and 1B ′ are respectively diagrams. 1 (a) is an enlarged view and a perspective view of an example of a protruding portion in the X1 portion, and FIGS. 1 (c) and 1 (c ′) are an enlarged view and a perspective view of another example of the X1 portion in FIG. 1 (a), respectively. It is.
Note that FIGS. 1D and 1E are perspective views showing examples of protrusions that serve as a reference of the present invention .

In particular, FIG. 1 (b) (b'), as shown in FIG. 1 (c) (c'), the reverse input blocking clutch according to the exemplary shaped state of the present invention, compared with the conventional example shown in FIG. 3, As an adhesion preventing portion for preventing the contact portion between the input shaft 12 and the output shaft 13 from sticking, a protrusion 19 is additionally provided around the central axis around the entire circumference . The same elements as those in FIG. 3 are denoted by the same reference numerals, and redundant description is omitted.

  As described above, the transmission mechanism of the reverse input cutoff clutch includes an input member 12A coupled to the input shaft 12 (in the reverse input cutoff clutch of the embodiment of FIG. 1, the input member 12A includes a separate input shaft 12). Are inserted in such a manner that they cannot rotate relative to each other), and an output member 13A provided on the output shaft 13 and a rolling member 17 that contacts the inner surface of the outer ring 14. And the plane part of 12 A of input members and the plane part of 13 A of output members are in the state which opposes. In order to prevent the rotational force from the output shaft 13, the opposing portion between the input shaft 12 and the output shaft 13 is free and smooth independent operation within a certain rotation range (the input shaft 12 and the output shaft 13 as described above). 13 relative free rotation).

In view of this, in the reverse input cutoff clutch of the embodiment of the present invention, the input shaft 12 and the output shaft 13 are configured so that the opposing portions of the input shaft 12 and the output shaft 13 do not come into contact with each other in a flat surface contact state and adhere to each other. The projecting portion 19 is provided over the entire circumference around the central axis at the opposite portion.

FIG.1 (b) is an enlarged view of an example of X1 part (protrusion part 19 part) of Fig.1 (a). The protrusion 19 is a contact area reduction part configured to reduce the contact area between the input member 12A and the output member 13A. In the case shown in FIG. 1B, the protrusion 19 is provided so as to protrude from the input member 12A. The tip portion thus formed is a protrusion having an R shape (the cross section is an arc). By making the tip part of the protrusion part into an R shape, the contact between the input member 12A and the output member 13A is a line contact. Therefore, even if an adhesive substance formed of oil such as grease and friction powder is generated, the input member 12A and the output member 13A can be prevented from sticking. Therefore, the abutment portion between the input shaft 12 and the output shaft 13 is not adhered and integrated, and a free and smooth independent operation in the constant rotation range of the output shaft 13 can be secured. Can prevent rotational force.
FIG. 1B 'is an overall perspective view of the input member 12A provided with the protrusion 19 shown in FIG. 1B and the opposed output member 13A (output shaft 13). As can be seen, the protrusion 19 is continuously formed around the central axis of the input shaft 12 (or the output shaft 13) over the entire circumference on the opposing surface of the input member 12A. Therefore, the tip of the protrusion 19 is in contact with the output member 13A over the entire circumference, and the input shaft 12 and the output shaft 13 can be prevented from being relatively inclined during rotation .

FIG. 1C is an enlarged view of another example of the X1 portion ( protrusion portion 19 portion) of FIG. Similar to FIG. 1B, the protrusion 19 is the same in that it is a contact area reducing unit configured to reduce the contact area between the input member 12A and the output member 13A. In FIG. 1C, the tip of the protrusion is trapezoidal, whereas the tip of the protrusion in FIG. By making the tip part of the protrusion a trapezoidal shape, the contact between the input member 12A and the output member 13A becomes a surface contact, but the contact area can be reduced, so that the adhesive formed by oil such as grease and friction powder Even if the substance is generated, the input member 12A and the output member 13A can be prevented from sticking in the same manner as in the case of FIG. Therefore, the abutment portion between the input shaft 12 and the output shaft 13 is not adhered and integrated, and a free and smooth independent operation in the constant rotation range of the output shaft 13 can be secured. Can prevent rotational force.
FIG.1 (c ') is a whole perspective view of 12 A of input members which provided the adhesion prevention part 19 shown in FIG.1 (c). The protrusion 19 in FIG. 1C is continuous over the entire circumference around the central axis of the input shaft 12 (or the output shaft 13) on the opposing surface of the input member 12A, as in FIG. 1B. Is formed.

FIG. 1 (d), the FIG. 1 (e) is the same perspective view as FIG. 1 (c') indicating the reference another example of X1 portions (projecting portions 19 portions) in FIG. 1 (a). Projections 19 'of FIG. 1 (d) Fig. 1 (c') was excised several places those ones were intermittently formed projections, also, projections 19 of FIG. 1 (e)' is A large number of independent hemispherical protrusions are formed on the opposing surface of the input member 12A. Since FIG. 1 (d) and the protrusions 19 'shown in FIG. 1 (e) are not continuous in the circumferential direction, as compared with those continuously formed a protrusion, it is possible to more effectively reduce the contact area, The generated adhesive substance flows in the radial direction and is easily removed.

FIG. 2 is an explanatory diagram of a reverse input cutoff clutch shown as a reference example in which rolling bodies are installed on opposing flat portions to form an adhesion preventing portion, and FIG. 2 (b) is an X2 portion of FIG. 2 (a) ( It is an enlarged view of the part of the rolling body used as an adhesion prevention part.

In FIG.2 (b), the adhesion prevention part is comprised as a rolling body 20 which provided the recessed part in the plane part which the input member 12A and the output member 13A oppose, and was installed in this recessed part . Thereby, a rolling body is rolled without making input member 12A and output member 13A contact directly. As the rolling body 20 , for example, a ball for bearing is used. Contact between the input member 12A and the output member 13A becomes an indirect contact via the rolling body 20, the contact is a point contact between the rolling body 20 the input member 12A or output member 13A, grease Even if the adhesive substance formed with the oil component and the friction powder is generated, the input member 12A and the output member 13A can be prevented from sticking. Therefore, the abutment portion between the input shaft 12 and the output shaft 13 is not adhered and integrated, and a free and smooth independent operation in the constant rotation range of the output shaft 13 can be secured. Can prevent rotational force.

Although the embodiments of the present invention have been described together with reference examples , these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms (for example, the protrusions 19 formed on the opposing surface of the input member 12A are formed on the opposing surface of the output member 13A). Various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 11 ... Reverse input interruption | blocking clutch, 12 ... Input shaft, 12A ... Input member, 12B ... Input engagement piece, 13 ... Output shaft, 13A ... Output member, 13B ... Output engagement piece, 14 ... Outer ring, 15 ... Cover part, DESCRIPTION OF SYMBOLS 16 ... Side wall part, 17 ... Rolling member, 18 ... Inner wall surface, 19, 19 ' ... Projection part (adhesion prevention part), 20 ... Rolling body (adhesion prevention part)

Claims (4)

An input shaft to which a rotational force is input, an output shaft that outputs the rotational force, and when the rotational force is applied to the input shaft, the output shaft is allowed to rotate and when the rotational force is applied to the output shaft, the input shaft A reverse input cut-off clutch comprising a transmission mechanism portion that prevents rotation of the motor and an outer ring that houses the transmission mechanism portion,
The input shaft and the output shaft are each formed with opposing flat portions, and the flat portions are housed in the outer ring together with oil such as grease,
One of the flat portions is formed with a protrusion that is continuous over the entire circumference around the central axis of the input shaft or the output shaft , and the tip of the protrusion is in contact with the other flat portion. A reverse input cut-off clutch characterized in that The reverse input cutoff clutch according to claim 1, wherein the protrusion has an arc shape in cross section . The reverse input cutoff clutch according to claim 1, wherein the protrusion has a trapezoidal cross section . The transmission mechanism portion has a rolling member that is pushed up by an output engagement portion provided on the output shaft,
4. The device according to claim 1, wherein when a rotational force is applied to the output shaft, the rolling member bites between the output engagement portion and the outer ring to prevent rotation of the input shaft. The reverse input cut-off clutch described in 1.