JP4509679B2 - Clutch and clutch unit - Google Patents

Description

  The present invention includes a clutch having a clutch function for transmitting only the rotational torque from the input side to the output side, and a reverse input blocking function for blocking the reverse input torque from the output side and not transmitting to the input side. It relates to the clutch unit that has it.

  In general, in a clutch unit using an engagement element such as a roller or a ball, a clutch portion is disposed between an input side member and an output side member. This clutch portion is composed of the input side member and the output side member described above. It is configured to control transmission / cutoff of input torque by engaging / disengaging rollers, balls, and other engaging elements in a wedge clearance formed therebetween.

  That is, when the engagement element engages with the wedge clearance, the input side member and the output side member transmit the input torque through the engagement element, while the engagement element separates from the wedge clearance, The member and the output side member can be idled relative to each other, and the input torque is blocked between the input side member and the output side member.

  FIG. 8 is a schematic view of the clutch portion that transmits and shuts off torque between the input side member and the output side member by engaging / disengaging the engagement element.

  As shown in the figure, the clutch portion transmits an outer ring 1 as an input side member to which torque is input, an inner ring 2 as an output side member from which torque is output, and an input torque from the outer ring 1 to the inner ring 2. A roller 3 as an engaging member, a cage 4 that holds the roller 3 in the circumferential direction, a stationary member 5 that is constrained to rotate, and a cage 4 and a stationary member 5 that are provided between the outer ring and the outer ring. A first centering spring 6 as a first elastic member that accumulates elastic force with an input torque from 1 and returns the cage 4 to a neutral state with the accumulated elastic force by releasing the input torque; The second elastic member is provided between the stationary member 5 and the stationary member 5 and accumulates an elastic force by the input torque from the outer ring 1 and releases the input torque to return the outer ring 1 to the neutral state by the accumulated elastic force. Second centering spring as member There is a structure provided with the bets (e.g., see Patent Document 1).

  In this clutch portion, a cam surface 1a is formed on the inner peripheral surface of the outer ring 1 with a wedge clearance 8 symmetrically in both the forward and reverse rotational directions between the outer ring 2a of the inner ring 2 at equal intervals in the circumferential direction. ing. The first and second centering springs 6 and 7 are both end ring-shaped leaf springs formed by rolling a strip material. In addition, when this clutch part is incorporated in the seat lifter part for automobiles, an operation lever (not shown) is connected to the outer ring 1 described above.

  As shown in FIG. 8, in a state where the input torque is not applied to the outer ring 1, the roller 3 is located between the outer ring 1 and the inner ring 2 at the center in the circumferential direction of the cam surface 1 a of the outer ring 1. It is not kept in the state.

  When an input torque acts on the outer ring 1, the outer ring 1 rotates with respect to the inner ring 2 as shown in FIG. 9 (see arrow A in the figure), so that the roller 3 is at one end side of the wedge clearance 8 (right side in the figure). ) And is engaged and engaged between the cam surface 1a of the outer ring 1 and the outer peripheral surface 2a of the inner ring 2. Thereby, the input torque from the outer ring 1 is transmitted to the inner ring 2.

On the other hand, when the input torque from the outer ring 1 is released, the cage 4 returns to the neutral state by the elastic restoring force of the first centering spring 6 as shown in FIG. The return torque (see arrow B in the figure) by the first centering spring 6 at that time is transmitted to the outer ring 1 via the cage 4 and the roller 3, and the outer ring 1 returns to the neutral state. Further, the second centering spring 7 assists the first centering spring 6 to reliably return the outer ring 1 to the neutral state with its elastic restoring force.
JP 2003-166555 A

  By the way, in the clutch portion described above, the return torque is applied to the cage 4 by the elastic restoring force of the first centering spring 6, the outer ring 1 is returned to the neutral state via the cage 4 and the roller 3, A restoring torque is applied to the outer ring 1 by the elastic restoring force of the second centering spring 7 to assist in restoring the outer ring 1 to the neutral state.

  Here, regarding the relationship between the return torque of the first centering spring 6 and the return torque of the second centering spring 7, the return torque of the second centering spring 7 is set larger than the return torque of the first centering spring 6. In this case, when the input torque from the outer ring 1 is released, the return torque of the second centering spring 7 is larger than the return torque of the first centering spring 6 as shown in FIG. The return operation of the outer ring 1 by the elastic restoring force of the second centering spring 7 (see the arrow C in the figure) is faster than the returning action of the cage 4 and the roller 3 by the elastic restoring force (see the arrow B in the figure). As a result, as shown in FIG. 11, the roller 3 is pushed into the other end side (left side in the figure) of the wedge clearance 8 and is engaged between the cam surface 1 a of the outer ring 1 and the outer peripheral surface 2 a of the inner ring 2. Nde become a locked state, the outer ring 1 there is a possibility that does not return to the neutral position.

  Therefore, the present invention has been proposed in view of the above-mentioned problems, and the object of the present invention is to appropriately define the relationship between the magnitudes of the return torques of the two centering springs, so that the outer ring as the input side member can be reduced. It is an object of the present invention to provide a clutch and a clutch unit that can surely return to a neutral position.

As technical means for achieving the above-described object, the present invention provides an input side member to which torque is input, an output side member to which torque is output, and an input torque from the input side member to the output side member. An engaging member, a retainer holding the engaging member, a stationary member whose rotation is restricted, and an elastic force accumulated by the input torque from the input member, provided between the retainer and the stationary member. And a first elastic member that returns the cage to a neutral state by the accumulated elastic force by releasing the input torque, and is provided between the input side member and the stationary side member. A clutch having a second elastic member that accumulates elastic force with torque and returns the input side member to a neutral state with the accumulated elastic force when the input torque is released, and is held by the first elastic member Return tor And T _1, the relationship between the return torque T ₂ acting on the input side member with a second elastic member, T ₁ / M ₁ ≧ by adding the inertia moment M _1, M ₂ of the cage and the input-side member It is defined by T ₂ / M ₂ , and the inertia moment of the cage is set smaller than the inertia moment of the input side member .

  Here, in order to eliminate the conventional problem caused by setting the return torque by the first elastic member to be smaller than the return torque by the second elastic member, the return torque by the first elastic member is It can be considered to set the torque larger than the return torque by the elastic member. Thus, in order to make the return torque by the first elastic member larger than the return torque by the second elastic member, if the first elastic member is a leaf spring, for example, the plate thickness and the plate width should be increased. Although it is good, it may cause the leaf spring to break due to stress problems.

Therefore, in the present invention, in defining the relationship between the return torque T ₁ acting on the cage by the first elastic member and the return torque T ₂ acting on the input side member by the second elastic member, and adding to the input-side inertia moment M _1, M ₂ of the members as well as specified in _{T 1 / M 1 ≧ T 2} / M 2, the moment of inertia of the cage to set smaller than the moment of inertia of the input-side member I made it. Thus, than the operation input member by the second elastic member is to return to the neutral state, the retainer by the first elastic member becomes faster operation to be returned to the neutral state, the input-side member It is possible to reliably return to the neutral state.

  The present invention is arranged in an input side member to which torque is input, an output side member from which torque is output, a stationary side member in which rotation is restricted, and a gap between the stationary side member and the output side member, A pair of engagement elements that control transmission of input torque from the input side member and blocking of reverse input torque from the output side member by engagement / disengagement between both members, and the pair of engagement elements, The present invention can also be applied to a clutch unit having a clutch portion with a reverse input blocking function provided with an elastic member that urges a separating force between the engagement elements.

  In addition, it is desirable that the present invention adopts a structure incorporated in an automobile seat lifter. Thus, when it is incorporated in the automobile seat lifter, the operability can be improved.

According to the present invention, in defining the relationship between the return torque T ₁ acting on the cage by the first elastic member and the return torque T ₂ acting on the input side member by the second elastic member, and adding to the input-side inertia moment M _1, M ₂ of the members as well as specified in _{T 1 / M 1 ≧ T 2} / M 2, that is set smaller than the moment of inertia of the input-side member to the moment of inertia of the cage by than operation input side member by the second elastic member is to return to the neutral state, the retainer by the first elastic member becomes faster operation to be returned to the neutral state, the neutral input-side member It is possible to reliably return to the state. As a result, when applied to, for example, an automobile seat lifter, the initial position return of the operation lever is ensured and the operability can be improved.

  The embodiment of the present invention includes a first clutch portion 11 (see FIG. 2) provided on the input side and a second clutch portion 12 (see FIG. 3) having a reverse input blocking function provided on the output side. The clutch unit (refer FIG. 1) is illustrated.

  As shown in FIGS. 1 and 2, the first clutch portion 11 includes an outer ring 13 as an input side member to which torque is input, an inner ring 14 as an output side member from which torque is output, and input torque from the outer ring 13. A plurality of rollers 15 as an engagement member that transmits the roller 15 to the inner ring 14, a cage 16 that holds the rollers 15 in the circumferential direction, a cage 16 and a stationary member (an outer ring 21 of the second clutch portion 12 described later). The first elastic member is provided as a first elastic member that accumulates elastic force with the input torque from the outer ring 13 and returns the cage 16 to the neutral state with the accumulated elastic force by releasing the input torque. The centering spring 17 is provided between the outer ring 13 and the stationary side member (the outer ring 21 of the second clutch portion 12). The elastic force is accumulated by the input torque from the outer ring 13, and is accumulated by releasing the input torque. The Comprising a second centering spring 18 as a second elastic member for returning the outer ring 13 to the neutral state by sex force.

  A plurality of cam surfaces 13 a are formed at equal intervals in the circumferential direction on the inner periphery of the outer ring 13. The outer ring 13 is connected to an operation lever (not shown) via a side plate 10 disposed coaxially, thereby constituting a part of an input side member of a seat lifter portion for adjusting a seat seat of an automobile, for example. . The inner ring 14 includes an outer peripheral surface 14 a that forms a wedge clearance 20 between the outer ring 13 and the cam surface 13 a of the outer ring 13. The retainer 16 includes a plurality of pockets 19 that accommodate the rollers 15 in a rollable manner and retain them at regular intervals in the circumferential direction.

  Each of the first and second centering springs 17 and 18 is an end ring-shaped leaf spring formed by rolling a strip material, and as shown in FIG. 4, the first centering spring 17 is radially inward. The second centering spring 18 has a pair of locking portions 17a bent outward in the radial direction. The first centering spring 17 is disposed on the inner diameter side of the second centering spring 18.

  The first centering spring 17 located on the inner diameter side is disposed between the retainer 16 and the outer ring 21 which is a stationary side member of the second clutch portion 12, and one locking portion 17 a is locked to the retainer 16. At the same time, the other locking portion 17 a is locked to a claw portion 21 a provided on the outer ring 21.

  In the first centering spring 17, when the input torque from the outer ring 13 is applied, one locking portion 17 a is engaged with a part of the cage 16, and the other locking portion 17 a is engaged with the claw portion 21 a of the outer ring 21. Accordingly, the first centering spring 17 is pushed and expanded with the rotation of the outer ring 13, and the elastic force is accumulated. When the input torque from the outer ring 13 is released, the retainer 16 is brought into a neutral state by the elastic restoring force. Return.

  The second centering spring 18 located on the outer diameter side is disposed between the outer ring 13 and the outer ring 21 which is a stationary side member of the second clutch portion 12, and both locking portions 18 a are provided on the outer ring 13. It is locked to the claw portion 13 b and is locked to the claw portion 21 b provided on the outer ring 21. The locking portion 18 a is arranged with a circumferential phase shifted from the locking portion 17 a of the first centering spring 17.

  In the second centering spring 18, when the outer ring 13 rotates during rotation when input torque acts from the outer ring 13, one locking portion 18 a is on the claw portion 13 b of the outer ring 13, and the other locking portion 18 a is on the outer ring. Since the second centering spring 18 is expanded and the elastic force is accumulated as the outer ring 13 rotates, the elastic restoring force is released when the input torque from the outer ring 13 is released. To return the outer ring 13 to the neutral state.

  In this embodiment, regarding the magnitude relationship between the return torque by the first centering spring 17 and the return torque by the second centering spring 18, the moment of inertia of the cage 16 (including the roller 15) and the outer ring 13 (including the side plate 10). ) And the moment of inertia.

That is, in defining the relationship between the return torque T ₁ acting on the cage 16 by the first centering spring 17 and the return torque T ₂ acting on the outer ring 13 by the second centering spring 18, The inertia moment M ₁ , M ₂ of the outer ring 13 is taken into account and defined as T ₁ / M ₁ ≧ T ₂ / M ₂ , and the inertia moment M ₁ of the cage 16 is set smaller than the inertia moment M ₂ of the outer ring 13. I tried to do it.

As a result, if the inertia moment M ₁ of the cage 16 is set to be smaller than the inertia moment M ₂ of the outer ring 13, the first centering spring 18 will cause the first operation to return to the neutral state. Since the operation of the cage 16 to return to the neutral state is accelerated by the centering spring 17, the outer ring 13 can be reliably returned to the neutral state.

The cage 16 is made of a material whose inertia moment is smaller than the inertia moment of the outer ring 13. That is, for example, the cage 16 is made of resin or aluminum with respect to the iron outer ring 13. In this way, it becomes easy to set the inertia moment M ₁ of the cage 13 to be smaller than the inertia moment M ₂ of the outer ring 13.

  The operation of the first clutch portion 11 in the clutch unit of this embodiment will be described with reference to FIGS. 5 to 7, the first and second centering springs 17 and 18 and the outer ring 21 which is a stationary side member of the second clutch portion 12 are schematically illustrated and conceptually illustrated.

  As shown in FIG. 5, in a state where no input torque is applied to the outer ring 13, the roller 15 is located between the outer ring 13 and the inner ring 14 at the center in the circumferential direction of the cam surface 13 a of the outer ring 13. It is not kept in the state.

  When input torque acts on the outer ring 13, the outer ring 13 rotates with respect to the inner ring 14 as shown in FIG. 6 (see arrow A in the figure), so that the roller 15 is at one end side of the wedge clearance 20 (right side in the figure). ) To be engaged and engaged between the cam surface 13a of the outer ring 13 and the outer peripheral surface 14a of the inner ring 14. Since the retainer 16 tries to stand still together with the outer ring 21 that is a stationary side member by the second centering spring 18, the outer ring 13 can be relatively moved.

  Thereby, since the outer ring 13 and the inner ring 14 are locked, the input torque from the outer ring 13 is transmitted to the inner ring 14 via the roller 15, and the outer ring 13, the roller 15, the retainer 16 and the inner ring 14 are rotated together. Move. As the outer ring 13 and the cage 16 rotate, the first centering spring 17 and the second centering spring 18 are bent, and an elastic force corresponding to the amount of the bending is accumulated.

  On the other hand, when the input torque from the outer ring 13 is released, the cage 16 returns to the neutral state by the elastic restoring force accumulated in the first centering spring 17 as shown in FIG. The return torque (see arrow B in the figure) by the first centering spring 17 at that time is transmitted to the outer ring 13 via the cage 16 and the roller 15, and the outer ring 13 returns to the neutral state. At the same time, the second centering spring 18 assists the first centering spring 17 to reliably return the outer ring 13 to the neutral state with the accumulated elastic restoring force.

At this time, as described above, the relationship between the return torque T ₁ acting on the cage 16 by the first centering spring 17 and the return torque T ₂ acting on the outer ring 13 by the second centering spring 18 is expressed as follows. In addition, the inertia moments M ₁ and M ₂ of the outer ring 13 are taken into account and defined by T ₁ / M ₁ ≧ T ₂ / M ₂ , and the inertia moment M ₁ of the cage 16 is smaller than the inertia moment M ₂ of the outer ring 13. by setting the, than the operation of the outer ring 13 tries to return to the neutral state by a second centering spring 18, since the retainer 16 by the first centering spring 17 becomes faster operation to be returned to the neutral state, As shown in FIG. 11, the roller 3 is pushed into the other end side (left side in the figure) of the wedge clearance 8 and is engaged between the cam surface 1 a of the outer ring 1 and the outer peripheral surface 2 a of the inner ring 2 to be locked. Not to become a state, it is possible to surely return to the neutral state the outer ring 13 as shown in FIG.

  On the other hand, as shown in FIGS. 1 and 3, the second clutch portion 12 having a reverse input blocking function in a type referred to as a lock type is a cage in which the inner ring 14 of the first clutch portion 11 functions as an input side member. Hereinafter, in the second clutch portion 12, it is referred to as a cage 14), an output shaft 22 as an output side member, an outer ring 21 as a stationary side member, and a clearance between the outer ring 21 and the output shaft 22, A pair of rollers 24 that controls transmission of input torque from the retainer 14 and interruption of reverse input torque from the output shaft 22 by engagement / disengagement between the two and a pair of rollers 24. The main part is constituted by a leaf spring 25 having an N-shaped cross section as an elastic member that urges a separation force between the rollers 24.

  As shown in FIG. 3, a polygonal cam surface 22a is formed on the outer diameter surface of the output shaft 22 described above. A polygonal cam surface 22a is formed between the inner ring surface 21a of the outer ring 21 and a wedge clearance 26 symmetrical in both forward and reverse rotation directions. It is formed at equal intervals in the circumferential direction. The retainer 14 disposed between the output shaft 22 and the outer ring 21 has concave pockets 23 opened in the axial direction at equal intervals in the circumferential direction, and a fixed side plate that is an end member on the open side. 30 is arranged. A pair of rollers 24 is accommodated in each pocket 23, and a leaf spring 25 for biasing the separating force between the rollers 24 is interposed between the rollers 24.

  On the other hand, the output shaft 22 is formed with a plurality of pin holes 22b at predetermined circumferential intervals, and the pins 14b of the retainer 14 are inserted into these pin holes 22b and connected with a detent structure. Further, the outer ring 21 is formed with locking portions (not shown) that engage with the first and second centering springs 17 and 18 of the first clutch portion 11, respectively.

  In the first clutch portion 11 described above, when input torque acts on the outer ring 13, the roller 15 engages with the wedge clearance 20, and torque is transmitted to the inner ring 14 via the roller 15, so that the inner ring 14 rotates. At this time, an elastic force is accumulated in the first and second centering springs 17 and 18 as the outer ring 13 and the cage 16 rotate. When the input torque disappears, the outer ring 13 and the retainer 16 return to the neutral state by the elastic force of the first and second centering springs 17 and 18, while the inner ring 14 maintains the given rotational position as it is. To do. Therefore, the rotation amount of the outer ring 13 is repeatedly accumulated in the inner ring 14 due to repeated rotation.

  On the other hand, in the second clutch portion 12, when reverse input torque is input from the output shaft 22 with no input torque acting on the cage 14, the roller 24 interposed between the output shaft 22 and the outer ring 21. However, the wedge spring 26 between the output shaft 22 and the outer ring 21 is engaged and locked by a leaf spring 25 that urges the separating force between the rollers 24. Therefore, the reverse input torque from the output shaft 22 is locked by the second clutch portion 12 and the return of the reverse input torque to the first clutch portion 11 is interrupted.

  On the other hand, the input torque from the outer ring 13 is input to the retainer 14 via the first clutch portion 11, and the retainer 14 is engaged with the roller 24 and pressed against the elastic force of the leaf spring 25. The roller 24 is removed from the wedge clearance 26 and the locked state of the output shaft 22 is released, and the output shaft 22 starts rotating together with the retainer 14. After the retainer 14 starts to rotate in this way, the pin 14b of the retainer 14 engages with the pin hole 22b of the output shaft 22, so that the input torque from the retainer 14 passes through the pin 14b and the pin hole 22b. Is transmitted to the output shaft 22 and the output shaft 22 rotates. When the input torque from the cage 14 is lost, the neutral state is restored by the elastic restoring force of the leaf spring 25.

  The present invention can be used by being incorporated in a drive mechanism such as an electric slide door, an electric back door, a power window, and an electric steering, in addition to being incorporated in, for example, an automobile seat lifter.

In embodiment of this invention, it is sectional drawing which shows the whole structure of a clutch unit. It is sectional drawing which follows the II line | wire of FIG. 1, and shows a 1st clutch part. It is sectional drawing which follows the II-II line | wire of FIG. 1, and shows a 2nd clutch part. It is sectional drawing in alignment with the III-III line | wire of FIG. 1, and shows a 1st and 2nd centering spring. FIG. 3 is an enlarged cross-sectional view of a main part illustrating a state in which a roller is in a neutral position for explaining the operation of the first clutch part of FIG. 2. FIG. 3 is an enlarged cross-sectional view of a main part for explaining the operation of the first clutch part of FIG. 2 and showing a state in which a roller is caught in a wedge clearance. FIG. 3 is an enlarged cross-sectional view of a main part illustrating a state in which a roller returns to a neutral position for explaining the operation of the first clutch part of FIG. 2. It is a principal part expanded sectional view for demonstrating operation | movement of the conventional clutch part, and showing the state which has a roller in a neutral position. It is for demonstrating operation | movement of the conventional clutch part, Comprising: It is a principal part expanded sectional view which shows the state which the roller bit | engaged in the wedge clearance. It is a principal part expanded sectional view for demonstrating operation | movement of the conventional clutch part, and showing the state which a roller returns to a neutral position. It is for demonstrating operation | movement of the conventional clutch part, and is a principal part expanded sectional view which shows the malfunction state by which the roller was locked.

Explanation of symbols

13 Input side member (outer ring)
14 Output side member (inner ring)
15 Engagement element (roller)
16 Cage 17 First elastic member (centering spring)
18 Second elastic member (centering spring)
21 Static side member (outer ring)

Claims (3)

An input side member to which torque is input, an output side member to which torque is output, an engagement element that transmits input torque from the input side member to the output side member, a cage that holds the engagement element, and rotation A restrained stationary member, and provided between the retainer and the stationary member, accumulate elastic force with input torque from the input member, and release the input torque to retain the accumulated elastic force. Is provided between the input side member and the stationary side member, accumulates an elastic force by an input torque from the input side member, and accumulates by releasing the input torque. And a second elastic member for returning the input side member to a neutral state by the elastic force, and a return torque T ₁ acting on the cage by the first elastic member and an input by the second elastic member Return acting on side member The relationship between the torque T _2, as well as specified in _{T 1 / M 1 ≧ T 2} / M 2 in consideration of the inertia moment M _1, M ₂ of the cage and the input-side member, the moment of inertia of the cage A clutch characterized in that it is set smaller than the moment of inertia of the input side member . The clutch according to claim 1 , which is incorporated in an automobile seat lifter. An input side member to which torque is input, an output side member to which torque is output, a stationary side member whose rotation is constrained, and a clearance between the stationary side member and the output side member are arranged between the two members. A pair of engagement elements that control transmission of input torque from the input side member and interruption of reverse input torque from the output side member by engagement / disengagement between the pair of engagement elements, and a pair of engagement elements. The clutch unit which added the clutch part of the reverse input interruption | blocking function provided with the elastic member which urges | biases a separation force to the clutch of Claim 1 or 2 .

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