Reverse-direction locking coupling and reverse-direction locking system

Abstract

A reverse-direction locking clutch (1) comprises a drive element (2), a driven element (3), and an engagement element (5) that engages with a drive engagement part (25) of the drive element (2) and an output engagement part (35) of the output element (3). The drive engagement part (25) comprises a first contact part (P1) and a second contact part (P2) that come into contact with the engagement element (5). The output engagement part (35) comprises an output contact part (Q1, Q2) that comes into contact with the engagement element (5). In a second radial direction (D2), a distance (MI1) between the first contact part (P1) and a first reference line (L1) is greater than a distance (MO1) between the output contact part (Q1) and the first reference line (L1). A distance (MI2) between the second contact part (P2) and the first reference line (L1) is smaller than a distance (MO2) between the output contact part (Q2) and the first reference line (L1).

Description

TECHNICAL AREA

[0001] The present invention relates to a reverse-direction locking coupling and a reverse-direction locking system. TECHNICAL BACKGROUND

[0002] Configurations of a reverse-direction locking clutch are known from the prior art. These include a drive element connected to a drive mechanism, for example, a power source, and a driven element connected to a drive mechanism, for example, a reduction gear. The drive element transmits torque from the drive element to the driven element and interrupts the reverse input of torque from the driven element to the drive element. A reverse-direction locking system using the reverse-direction locking clutch is also known. Various techniques for improving the performance of the reverse-direction locking clutch and the reverse-direction locking system have been proposed.

[0003] For example, patent document 1 (PCT International Publication No. WO 2022 / 168466) discloses a configuration of a reverse-direction locking clutch comprising a pressed element with a pressed surface, a drive element and an output element which are provided such that they are coaxial to each other in a radial direction on the inside of the pressed surface, and a pair of engagement elements which are provided in a front view between the drive element and the output element and which are movable in the radial direction.

[0004] In the technique described in patent document 1, the engagement elements move in a direction in which they approach the pressed surface and, due to the engagement between the engagement elements and the output element, come into frictional engagement with the pressed surface when a torque in the reverse direction is applied to the output element, so that the torque applied in the reverse direction to the output element can be switched off or disconnected. DESCRIPTION OF THE INVENTION Technical Problem

[0005] On the other hand, the technique of transmitting torque or interrupting (locking) a torque applied in the reverse direction through contact between the drive element and the engagement elements, and contact between the driven element and the engagement elements, as described in the related prior art, presents the following problems. When a reverse application occurs, the engagement elements may have difficulty moving radially outward and locking according to the contact positions between the drive element and the engagement elements, or between the driven element and the engagement elements. If a forward application is required to unlock the engagement, the torque required to unlock the engagement may increase depending on the contact positions between the components, potentially reducing the efficiency of the torque transmission.

[0006] Accordingly, there is a problem in the state of the art with regard to improving both the blocking performance against reverse input and the efficiency of torque transmission during forward input.

[0007] Therefore, it is an object of the present invention to provide a reverse-direction locking clutch that can improve both the locking performance against reverse input and the efficiency of torque transmission during forward input compared to those in the related prior art, as well as a reverse-direction locking system comprising the reverse-direction locking clutch. Solution to the problem

[0008] To solve the aforementioned problem, the present invention proposes the following means.

[0009] A reverse-direction locking clutch according to a first aspect of the present invention comprises: a housing with a pressed surface on an inner circumferential surface; a drive element with a drive shaft arranged such that it is coaxial with the pressed surface, and a pair of drive engagement parts arranged such that they are separated from each other in a first radial direction, with a central axis of the drive shaft arranged between them; a driven element with an output shaft arranged such that it is coaxial with the drive shaft, and an output engagement part arranged in the first radial direction between the pair of drive engagement parts, and a pair of engagement elements comprising a pressed surface facing the pressed surface, a drive-engaged part capable of engaging with the drive engagement part, and an output-engaged part.which is capable of engaging with the output engagement part, wherein the engagement elements are relatively movable in the first radial direction, wherein, when a torque is applied to the drive element, the pair of engagement elements moves to approach each other inwards in the first radial direction based on the engagement between the drive-engaged part and the drive-engaged part, and transmits the torque to the output element based on the engagement between the output-engaged part and the output engagement part, wherein, when a torque is applied in the opposite direction to the output element, the pair of engagement elements moves such that they separate from each other outwards in the first radial direction, and causesthat the pressed surface and the pressing surface engage with each other in a frictional engagement, wherein a pair of the drive engagement parts is designed such that they are point-symmetric with respect to a central axis of the drive element when viewed in an axial direction of the drive element, wherein each drive engagement part has a first contact part that comes into contact with the corresponding engagement element when the torque is applied to the drive element in a first direction of rotation, and a second contact part that comes into contact with the corresponding engagement element when the torque is applied to the drive element in a second direction of rotation opposite to the first direction of rotation, wherein the output engagement part has an output contact part that comes into contact with the engagement elements when the torque is applied to the output element in the opposite direction, and wherein,If a direction perpendicular to both the first radial direction and the central axis of the drive element is defined as a second radial direction, and a distance in the second radial direction between the first contact part and a center of rotation of the drive element is greater than a distance in the second radial direction between the output contact part and the center of rotation of the drive element, and a distance in the second radial direction between the second contact part and the center of rotation of the drive element is less than the distance in the second radial direction between the output contact part and the center of rotation of the drive element.

[0010] A reverse-direction locking system according to the first aspect of the present invention comprises the aforementioned reverse-direction locking coupling and a ball screw spindle mechanism connected to the output element of the reverse-direction locking coupling. Advantageous effects of the invention

[0011] With the reverse-direction locking clutch and the reverse-direction locking system according to the present invention, it is possible to provide a reverse-direction locking clutch that can improve both the locking performance against reverse input and the efficiency of the torque transmission for forward input compared to the prior art, as well as a reverse-direction locking system that includes the reverse-direction locking clutch. BRIEF DESCRIPTION OF THE DRAWINGS [ Fig. 1] A representation schematically showing a configuration of a counter-directional locking system according to a first embodiment. [ Fig. 2] A sectional view of the reverse-direction locking coupling according to the first embodiment. [ Fig. 3] A sectional view along line III-III in Fig. 2. [ Fig. 4] A diagram schematically showing the effect of the reverse-direction locking clutch according to the first embodiment. [ Fig. 5] A representation schematically showing an effect at the time of unlocking the opposite-direction locking coupling according to the first embodiment. [ Fig. 6] A diagram schematically showing an effect at the time of unlocking a reverse-direction locking coupling according to a comparative example. [ Fig. 7] A diagram schematically showing an effect at the time of unlocking a reverse-direction locking coupling according to a comparative example. [ Fig. 8] A sectional view of a reverse-direction locking coupling according to a second embodiment. DESCRIPTION OF EXECUTION FORMS

[0012] Embodiments of the present invention are described below with reference to the accompanying drawings. In the following description, an axial direction, a radial direction, and a circumferential direction refer to an axial direction, a radial direction, and a circumferential direction of a central axis C of a counter-directional locking coupling 1, unless otherwise stated. The direction that is parallel to a direction (a facing direction) in which a pair of engagement elements, which will be described later, approach each other and are separated from each other in the radial direction, may be designated as a first radial direction D1, and a direction that is perpendicular to both the first radial direction D1 and the radial direction may be designated as a second radial direction D2. (First embodiment) (counter-direction locking system)

[0013] Fig. Figure 1 is a representation that schematically depicts a configuration of a counter-directional locking system 10 according to a first embodiment.

[0014] As in Fig. Figure 1 shows a reverse-direction locking system 10 according to this embodiment being used as an electric caliper brake for a vehicle, for example, a motor vehicle. The reverse-direction locking system 10 is a system that implements a parking brake function of an electric caliper brake using a locking function (a function to interrupt reverse entry) of a reverse-direction locking clutch 1, the details of which are described later. The reverse-direction locking system 10 comprises a motor 11, a reverse-direction locking clutch 1, a ball recirculation mechanism 12, and a pair of brake pads 13 that clamp a brake disc 14 of a vehicle.

[0015] The motor 11 is a drive source in the counter-directional locking system 10, and a drive element 2 (a drive shaft) (see Fig. 2) The reverse-direction locking clutch 1 is connected to a rotating shaft of the motor 11. An input from the motor 11 is a forward input in the reverse-direction locking clutch 1.

[0016] The ball screw spindle mechanism 12 is connected to an output element 3 (an output shaft) (see Fig. 2) connected to the reverse-direction locking clutch 1. The ball screw mechanism 12 comprises a ball screw 15 connected to the output element 3 of the reverse-direction locking clutch 1, a nut 16 (a linear motion component in the claims) screwed onto the ball screw 15, and balls 17 positioned between the ball screw 15 and the nut 16. The ball screw mechanism 12 converts a rotary motion transmitted from the motor 11 to the ball screw 15 via the reverse-direction locking clutch 1 into a translational motion of the nut 16.

[0017] The rotating shaft of the motor 11 and the central axis of the ball screw mechanism 12 are both arranged coaxially with the central axis C of the reverse-direction locking clutch 1. In the following description, the side of the motor 11 with respect to the reverse-direction locking clutch 1 in a direction parallel to the central axis C can be referred to as a first side in the axial direction, and an opposite side (the side of the ball screw mechanism 12 with respect to the reverse-direction locking clutch 1) can be referred to as a second side in the axial direction.

[0018] The brake pad 13 is connected to the nut 16 of the ball screw mechanism 12. When the motor 11 is rotated in one direction, the nut 16 and the brake pad 13 move axially to the other side to approach the brake disc 14, and the brake disc 14 is clamped by a pair of brake pads 13, thus braking the vehicle. When the motor 11 is rotated in the other direction, the nut 16 and the brake pad 13 move axially to the first side to disengage from the brake disc 14, thus releasing the brakes.

[0019] When the motor shaft 11 rotates counterclockwise in the axial direction from the first side, the ball screw mechanism 12 is configured such that the nut 16 moves axially to the second side, i.e., in a direction in which the nut 16 approaches the brake disc 14. When the motor shaft 11 rotates clockwise in the axial direction from the first side, the nut 16 moves axially to the first side, i.e., in a direction in which the nut 16 is or becomes separated from the brake disc 14.

[0020] Since the ball screw mechanism 12 has a high reversing efficiency, the ball screw 15, which is a rotating component, can rotate, for example, when an axial thrust is exerted on the nut 16 due to a reaction force from the brake disc 14. To prevent this, according to the prior art, it is necessary to operate the motor 11 normally at the time of parking braking so that the ball screw 15 does not rotate. However, since the motor 11 is driven normally, the power consumption is likely to increase.

[0021] Therefore, in the reverse-direction locking system 10 according to this embodiment, a configuration is used in which the ball screw mechanism 12 and the reverse-direction locking clutch 1 are combined to transmit a forward input from the motor 11 to the ball screw mechanism 12 and to interrupt a reverse input from the ball screw mechanism 12 to the motor 11 using the reverse-direction locking clutch 1. Accordingly, it is possible to perform a normal parking brake application without driving the motor 11 because a reaction force from the brake disc 14 is interrupted by the reverse-direction locking clutch 1. (Counter-directional locking coupling)

[0022] The opposite-direction locking coupling 1 is described in detail below.

[0023] Fig. Figure 2 is a sectional view of the opposite-direction locking coupling 1 according to the first embodiment, viewed in a direction perpendicular to the axial direction. Fig. 3 is a sectional view along line III-III in Fig. 2.

[0024] As in the Fig. 2 and Fig. As shown in Figure 3, the reverse-direction locking coupling 1 comprises a drive element 2, a driven element 3, a housing 4, a pair of engagement elements 5, and an elastic element 6. The reverse-direction locking coupling 1 transmits a torque applied to the drive element 2 to the driven element 3. Conversely, the reverse-direction locking coupling has a function for interrupting the reverse application of torque, in order to switch off a torque acting in the opposite direction on the driven element 3 and the drive element 2, or to transmit only a portion of the torque to the drive element 2 and disconnect the remainder. (Drive element)

[0025] The drive element 2 is connected to the rotating shaft of the motor 11 (see Fig. 1) A rotational force from the motor 11 is transmitted to the drive element 2. The drive element 2 comprises a drive shaft body 21 (referred to as a drive shaft in the claims) and a pair of arms 23. The drive shaft body 21 has a columnar (or cylindrical) shape centered on the central axis C.

[0026] The pair of arms 23 extends axially from the drive shaft body 21 to the second side. The arms 23 are integrally formed with the drive shaft body 21. The pair of arms 23 extends at both ends in the first radial direction D1 of the drive shaft body 21. The arms 23 are positioned slightly outward in the radial direction from the drive shaft body 21. As shown in Fig. As shown in Figure 3, a straight line passing through the central axis C and parallel to the first radial direction D1 is defined as the first reference line L1. A straight line passing through the central axis C and parallel to a second radial direction D2, perpendicular to both the first radial direction D1 and the axial direction, is defined as the second reference line L2. The arms 23 are configured asymmetrically with respect to the first reference line L1. The pair of arms 23 is configured such that, viewed in the axial direction, it is point-symmetrical with respect to the central axis C. In particular, each arm 23 comprises a drive engagement part 25 with a nearly flat shape, located inwards in the first radial direction D1, a curved part 26, located outwards in the first radial direction D1, and a side part 27, which is provided only on one side in the second radial direction D2 with respect to the first reference line L1.The curved part 26 is arc-shaped and curved outwards in the first radial direction D1. The side part 27 connects the ends of the drive engagement part 25 and the curved part 26. One end of the drive engagement part 25 and one end of the curved part 26 are directly connected on the other side in the second radial direction D2, where the side part 27 is not provided with respect to the first reference line L1.

[0027] Two or more arms 23 are provided, corresponding to the number of engagement elements 5 described later. Since a pair of engagement elements 5 is provided in this embodiment, a pair of arms 23 is also provided. The number of arms 23 is not limited to two and can be one, three, or more, depending on the number of engagement elements 5. (Output element)

[0028] As in Fig. As shown in Figure 2, the output element 3 is equipped with the ball screw spindle 15 (see Figure 2). Fig. 1) of the ball screw mechanism 12 and transmits a rotational force (a torque) from the motor 11. The output element 3 is arranged coaxially with the input element 2. As shown in the Fig. 2 and Fig. As shown in Figure 3, the output element 3 comprises an output shaft body 31 (in the claims an output shaft) and an insertion part 32. The output shaft body 31 is columnar (or cylindrical) and centered on the central axis C.

[0029] The insertion part 32 extends axially from an end on the first side of the output shaft body 31 to the first side. The insertion part 32 is integrally formed with the output shaft body 31. The insertion part 32 is a part that is inserted between a pair of engagement elements 5, which will be described later, and is arranged radially on the inside of the pair of arms 23 of the drive element 2. In this embodiment, a base end part (for example, a part extending axially on the second side of a snap ring 39) is included. Fig. The base end of the insertion part 32, which is inserted between the pair of engagement elements 5, is formed in a plate shape. The shape of the base end of the insertion part 32 is not limited to a plate shape. A distal end (for example, a part located on the first side in the axial direction of the snap ring 39) of the insertion part 32 is column-shaped. The distal end of the insertion part 32 is attached to the drive element 2 via a bearing 46 such that both are rotatable relative to each other. The bearing 46 is, for example, a rolling bearing or a sliding bearing.

[0030] As in Fig. As shown in Figure 3, the outer circumferential surface of the base end part of the insertion part 32 comprises a pair of output engagement parts 35, arranged on both sides in one thickness direction of the insertion part 32 (the first radial direction D1), and a pair of side parts 36, which connect the ends of the pair of output engagement parts 35. Each output engagement part 35 is designed as a flat surface parallel to the second radial direction D2. The output engagement parts 35 are opposite the corresponding engagement elements 5. The output engagement parts 35 are provided on the inside in the first radial direction D1 of the drive engagement parts 25 of the drive element 2. The pair of side parts 36 connects the ends of the output engagement parts 35.

[0031] The output engagement parts 35 and the side parts 36 of the insert part 32 are designed to correspond to the number of engagement elements 5 described later. Since a pair of engagement elements 5 is provided in this embodiment, one pair of output engagement parts 35 and one pair of side parts 36 are provided. The number of output engagement parts 35 is not limited to two and can be one, three, or more, corresponding to the number of engagement elements 5. (Housing)

[0032] The housing 4 has a cylindrical shape. The housing 4 is attached to another element (not shown) so that its rotation is restricted. The housing 4 is arranged so that it is coaxial with the drive element 2 and the driven element 3. The housing 4 accommodates the drive element 2, the driven element 3, and a pair of engagement elements 5. The housing 4 comprises a first housing hole 41, a second housing hole 42, and a pressed surface 40.

[0033] As in Fig. As shown in Figure 2, the first housing hole 41 penetrates the housing 4 in the axial direction. The first housing hole 41 is designed such that it runs coaxially to the central axis C. The first housing hole 41 is provided on the second side of the housing 4 in the axial direction. The output shaft body 31 of the output element 3 is received in the first housing hole 41. The inner diameter of the first housing hole 41 is larger than the outer diameter of the output shaft body 31 of the output element 3. The first housing hole 41 rotatably holds the output element 3 via a bearing 45.

[0034] The second housing hole 42 is provided on the first side of the housing 4 in the axial direction. The second housing hole 42 is designed to be coaxial with the central axis C. The second housing hole 42 is provided on the first side of the housing 41 in the axial direction. The inner diameter of the second housing hole 42 is larger than the inner diameter of the first housing hole 41. Accordingly, a stepped through-hole is formed in the housing 4 by the first housing hole 41 and the second housing hole 42. The arms 23 of the drive element 2 are received in the second housing hole 42. The insertion part 32 of the output element 3 is received on the inside of the second housing hole 42 and on the inside of the arms 23. The inner diameter of the second housing hole 42 is larger than the outer diameter of the pair of arms 23 of the drive element 2.The drive element 2 is received in the second housing hole 42 in such a way that the drive element 2 is rotatable relative to the housing 4.

[0035] The inner circumferential surface of the second housing hole 42 serves as a pressed surface 40. The pressed surface 40 is coaxial with the central axis C. The drive engagement parts 25 of the drive element 2 and the output engagement parts 35 of the output element 3 are provided in the radial direction on the inside of the pressed surface 40. (Intervention element)

[0036] As in the Fig. 2 and Fig. As shown in Figure 3, each of the two engagement elements 5 is semicircular and arranged radially on the inside of the housing 4. The pair of engagement elements 5 is configured such that they face each other in the first radial direction D1 and move such that they either approach or separate each other in the first radial direction D1. Each of the pair of engagement elements 5 comprises a pressing surface 51, a bottom surface 52, a drive-engaged part 55, and an output-engaged part 56.

[0037] As in Fig. As shown in Figure 3, the pressing surface 51 is an outer surface in the radial direction that presses against the pressed surface 40 of the housing 4 and is an arcuate convex surface. A portion of the outer circumferential surface of the engagement element 5, facing the pressed surface 40, can serve as the pressing surface 51. The pressing surface 51 presses against the pressed surface 40 in a state where the reverse-direction locking clutch 1 is locked (a state where reverse input from the output element 3 has been interrupted). The radius of curvature of the pressing surface 51 is equal to or less than the radius of curvature of the pressed surface 40. The pressing surface 51 is provided at two positions on an engagement element 5 and is designed such that a frictional engagement force between the engagement element 5 and the pressed surface 40 is increased due to a wedge effect.Two contact surfaces 51 are provided at positions separated from each other in a circumferential direction of the engagement element 5. The contact surface 51 can be formed by the entire outer circumferential surface of the engagement element 5 or a part thereof, or it can be designed such that it has surface properties and conditions in which one part of the engagement element 5 has a greater coefficient of friction than the other part. For example, the contact surface 51 can be formed from a friction material that is attached to the engagement element 5 by bonding, adhesion, or the like. The contact surfaces 51 of the engagement elements 5 are in radial contact with the inside of the housing 4.

[0038] The base surface 52 of each engagement element 5 extends further on its inner side in the first radial direction D1 than the pressing surface 51. In particular, the base surface 52 forms a flat, semicircular portion of the engagement element 5 together with the drive-engaged portion 56 of the engagement element 5, which will be described later. In this embodiment, the base surface 52 has a flat surface shape, except for a pair of projections 59, which will be described later. The base surfaces 52 of a pair of engagement elements 5 face each other in the first radial direction D1.

[0039] The inner radius of the pressed surface 40 and the outer size of the engagement elements 5 are set such that, in a state in which the pair of engagement elements 5 is arranged in the housing 4, there is clearance in at least one of the spaces between the pressed surface 40 and the pressing surface 51 and in a space between the pair of bottom surfaces 52 and the output element 3.

[0040] The drive-engaged part 55 is a hole that, viewed in the axial direction, penetrates the center of the engagement elements 5. The drive-engaged part 55 has the form of an elongated hole extending in the second radial direction D2. The arms 23 of the drive element 2 are inserted into the drive-engaged part 55. The drive-engaged part 55 engages the arms 23. The drive-engaged part 55 is sized to allow the arms 23 of the drive element 2 to be loosely inserted into it. In particular, the drive-engaged part 55 is designed such that a gap exists between the arms 23 and the inner circumferential surface of the drive-engaged part 55 when the arms 23 of the drive element 2 are inserted into the drive-engaged part 55.Accordingly, in a neutral state in which the engagement elements 5 are not locked and no torque is applied, the arms 23 can be slightly displaced in the direction of rotation of the drive element 2 with respect to the drive-engaged part 55 (i.e. the engagement elements 5), and the engagement elements 5 can be slightly displaced in the first radial direction D1 with respect to the arms 23.

[0041] The output-engaged part 56 is located near the center in the second radial direction D2 of the flat part (the base surface 52) of the engagement elements 5 and has a semicircular shape. The output-engaged part 56 is located on the inside in the first radial direction D1 of the drive-engaged part 55. The insertion part 32 of the output element 3 engages with the output-engaged part 56. The output-engaged part 56 has a flat surface shape that extends continuously from the base surface 52.

[0042] A pair of projections 59, extending from the base surface 52 of one engagement element 5 to the other engagement element 5, are integrally formed with the base surfaces 52 of the engagement elements 5. The projections 59 are provided as a pair separated in the second radial direction D2 on the base surface 52 of one engagement element 5. The pair of projections 59 is located on the inside of the outermost end of the base surface 52 and on the outside of the drive-engaged part 56 in the second radial direction D2. The projection height of the projections 59 is set to a height at which the projections 59 of the pair of engagement elements 5, which are opposite each other in the first radial direction D1, are facing each other with a gap in the first radial direction D1 in a state in which the engagement elements 5 are disengaged (a state in which the transmission of a rotational force from the drive element 2 to the driven element 3 is permissible).

[0043] In a state where the opposite-direction locking clutch 1 is engaged as described in the Fig. 2 and Fig. As shown in Figure 3, the arms 23 of the drive element 2 are inserted axially into the drive-engaged parts 55 of the pair of engagement elements 5, and the insertion part 32 of the output element 3 is inserted axially between the output-engaged parts 56 of the pair of engagement elements 5. That is, the pair of engagement elements 5 is arranged such that the insertion part 32 of the output element 3 is positioned radially from the outside between the output-engaged parts 56.

[0044] As in Fig. As shown in Figure 2, end plates 38 are provided on both sides of the engagement elements 5 in the axial direction for positioning the elements in the axial direction. A snap ring 39 for positioning the elements is provided on one side in the axial direction of the engagement elements 5. Components such as the end plates 38 can, in addition to their positioning function, also have the function, for example, of preventing contact between the engagement elements 5 and the output element 3 as well as the drive element 2 in order to reduce wear. (Elastic element)

[0045] As in Fig. As shown in Figure 3, an elastic element 6 is elastically clamped between the engagement elements 5 and the output element 3. The elastic element 6 is, for example, a leaf spring. The elastic element 6 pushes the engagement elements 5 outwards in the first radial direction D1, i.e., in the direction in which the engagement elements 5 approach the contact surfaces 40. The elastic element 6 is, for example, designed as a flat plate in its entirety. Notches (not shown) are formed at both ends of the elastic element 6 in the second radial direction D2. The elastic element 6 is positioned by fitting the pair of projections 59 of the engagement elements 5 into the notches.

[0046] The elastic element 6 does not need to be provided. Here, the configuration according to this embodiment with the elastic element 6 is superior insofar as the generation of rattles due to gaps between components can be contained by the preload force of the elastic element 6, and the engagement elements 5 can easily move outwards in the first radial direction D1 to easily block a reverse entry by the preload force of the elastic element 6.

[0047] A positional relationship between the drive element 2 or the output element 3 and the contact parts of the engagement elements 5 is described below.

[0048] As in Fig. As shown in Figure 3, the drive engagement part 25 of the drive element 2 comprises, viewed in the axial direction, a first contact part P1 and a second contact part P2. The first contact part P1 is located near a boundary between the drive engagement part 25 and the curved part 26. When a counterclockwise torque (a first direction of rotation in the claims) is applied to the drive element 2, the drive element 2 rotates counterclockwise and engages with the engagement elements 5 on the first contact part P1. Here, counterclockwise CCW is a direction of rotation of a torque that is applied to the drive element 2 at the time a brake is actuated. That is, in this embodiment, a direction of rotation, for example, when the motor 11 is driven to press the brake pad 13 against the brake disc 14, is the counterclockwise direction CCW.The direction of rotation at the time the brake is released is clockwise (CW).

[0049] The second contact part P2 is located near the boundary between the drive engagement part 25 and the side part 27. The second contact part P2 comes into contact with the engagement elements 5 when a clockwise torque CW (a second direction of rotation in the claims) is applied to the drive element 2. A distance MI1 in the second radial direction D2 from the first reference line L1 to the first contact part P1 (hereinafter referred to as the drive-side first distance MI1) is greater than a distance MI2 in the second radial direction D2 from the first reference line L1 to the second contact part P2 (hereinafter referred to as the drive-side second distance MI2) (MI1 > MI2).

[0050] Viewed in the axial direction, the output engagement part 35 of the output element 3 comprises a third contact part Q1 (an output contact part in the claims) and a fourth contact part W2 (an output contact part in the claims). The third contact part Q1 is located in the same region as the corresponding first contact part P1, within four regions defined by the first reference line L1 and the second reference line L2. The third contact part Q1 is located near the boundary between the output engagement part 35 and the side part 36. The third contact part Q1 comes into contact with the engagement elements 5 when a clockwise torque CW is applied to the output element 3. Here, clockwise direction CW is a direction of rotation of a torque applied in the opposite direction to the output element 3.In this embodiment, for example, one direction in which the ball screw spindle 15 is to rotate due to a reaction force from the brake disc 14 is the clockwise direction CW. Accordingly, in this embodiment, the direction of rotation of the torque applied in the opposite direction to the reverse locking clutch 1 is mainly the clockwise direction CW.

[0051] The fourth contact part Q2 is located in the same area as the corresponding second contact part P2, within four areas defined by the first reference line L1 and the second reference line L2. The fourth contact part Q2 is situated near the boundary between the output engagement part 35 and the side part 36. The fourth contact part Q2 comes into contact with the engagement elements 5 when a counterclockwise torque CCW is applied to the output element 3. A distance MO1 in the second radial direction D2 from the first reference line L1 to the third contact part Q1 (hereinafter referred to as the output-side first distance MO1) is equal to a distance MO2 in the second radial direction D2 from the first reference line L1 to the fourth contact part Q2 (hereinafter referred to as the output-side second distance MO2) (MO1=MO2).

[0052] In the following description, the third contact part Q1 and the fourth contact part Q2 can be referred to as one output contact part if they are not distinguished from each other.

[0053] The first distance MI1 on the drive side is greater than the first distance MO1 on the output side (MI1 > MO1). The second distance MI2 on the drive side is smaller than the second distance MO2 on the output side (MI2 < MO2).

[0054] In a state where a torque in the reverse direction is applied to the output element 3 and the pair of pressing surfaces 51 is in contact with the pressed surface 40, the output-side contact parts Q1 and Q2 are located in the first radial direction D1 closer to the center of rotation C of the output element 3 than a virtual straight line LH connecting a contact part P5 between a pressing surface 51 from the pair of pressing surfaces 51 and the pressed surface 40 and the center of rotation C of the output element 3. (How the reverse-direction locking coupling works)

[0055] The operation of the opposite-direction locking coupling 1 and the opposite-direction locking system 10 according to this embodiment is described below with reference to the drawings.

[0056] First, a case is described in which the engine 11 (see Fig. 1) is driven to actuate the brake. When the brake is to be actuated, the motor 11 is first rotated counterclockwise CCW. When a rotational force is applied from the motor 11 to the drive element 2, as shown in Fig. As shown in Figure 3, the arms 23 of the drive element 2 rotate counterclockwise with respect to the central axis C. Then, the first contact part P1 comes into contact with the engagement elements 5 to press the inner surface of the drive-engaged part 55 inwards in the first radial direction D1, and thus the pair of engagement elements 5 moves towards each other. Then, the insertion part 32 of the output element 3 is clamped from both sides in the radial direction by the output-engaged parts 56 of the pair of engagement elements 5, which are moving towards each other.

[0057] Accordingly, the output engagement part 35 of the insertion part 32 of the output element 3 becomes almost parallel to the base surfaces 52 of the engagement elements 5, and the insertion part 32 and the pair of output-engaged parts 56 engage with each other without rattling. Accordingly, the torque applied to the drive element 2 is transmitted via the pair of engagement elements 5 to the output element 3 and from the output element 3 to the ball screw mechanism 12.

[0058] When the ball screw spindle 15 of the ball screw spindle mechanism 12 rotates counterclockwise, the nut 16 and the brake pad 13 move in the axial direction towards the brake disc 14. As a result, the brake disc 14 is clamped by the brake pad 13 and the brake functions.

[0059] The following describes a case in which a reaction force acts from the brake disc 14 after the brake has been applied. Specifically, it describes a case in which a thrust is generated on the first side in the axial direction in the nut 16 of the ball screw mechanism 12, and a reverse input is applied to the counter-direction locking clutch 1 via the ball screw 15 due to this thrust. When a torque in the reverse direction is applied to the output element 3, the insertion part 32 of the output element 3 rotates clockwise CW within the pair of output-engaged parts 56. Then, the third contact part Q1 comes into contact with the engagement element 5 to push the output-engaged part 56 outwards in the first radial direction D1, and thus the pair of engagement elements 5 moves in directions in which they approach the pressed surface 40.Then the pressing surfaces 51 of the pair of engagement elements 5 are pressed against the pressed surface 40 of the housing 4. The pressing surfaces 51 and the pressed surface 40 engage fully or partially in a frictional manner in the circumferential direction of the pressing surfaces 51.

[0060] As a result, the torque applied in the reverse direction to the output element 3 is transferred to the housing 4, which is attached to another element (not shown), and is completely cut off and not transferred to the drive element 2. Alternatively, only a portion of the torque applied in the reverse direction to the output element 3 is transferred to the drive element 2, and the remainder is cut off. In particular, in this embodiment, the reverse input is completely interrupted and is not transferred to the drive element 2.

[0061] Accordingly, it is possible to brake the rotation of the ball screw spindle 15, which is associated with the generation of a reaction force of the brake disc 14, even when the motor 11 stops. Consequently, it is possible to perform a parking brake using the reverse-direction locking clutch 1.

[0062] The following describes a case in which the engine 11 (see Fig. 1) is driven again to release the brake. When the brake is to be released, the motor 11 is first rotated clockwise CW. When a rotational force is applied from the motor 11 to the drive element 2, as shown in Fig. As shown in Figure 3, the arms 23 of the drive element 2 rotate clockwise CW with respect to the central axis C. Then the second contact part P2 comes into contact with the engagement element 5 to press the inner surface of the drive-engaged part 55 inwards in the first radial direction D1, and thus the pair of engagement elements 5 moves towards each other. Then the insertion part 32 of the output element 3 is clamped from both sides in the radial direction by the output-engaged parts 56 of the pair of engagement elements 5, which are approaching each other.

[0063] Accordingly, the output engagement part 35 of the insertion part 32 of the output element 3 becomes almost parallel to the bottom surfaces 52 of the engagement elements 5, and the insertion part 32 and the pair of output-engaged parts 56 engage with each other without rattling. Accordingly, the torque applied to the drive element 2 is transmitted via the pair of engagement elements 5 to the output element 3 and from the output element 3 to the ball screw mechanism 12.

[0064] When the ball screw spindle 15 of the ball screw mechanism 12 rotates clockwise, the nut 16 and the brake pad 13 move to separate from the brake disc 14 in the axial direction. As a result, the brake pad 13 is separated from the brake disc 14 and the brake is released.

[0065] The size of the gaps between the components is adjusted so that the opposite-direction locking coupling 1 can perform the aforementioned processes according to this embodiment.

[0066] For example, the drive element 2 is in a neutral position when a torque is applied in the reverse direction to the output element 3, thus bringing the contact surfaces 51 of the engagement elements 5 into contact with the pressed surface 40 (in the locked state). The neutral position of the drive element 2 is a position in which the drive engagement parts 25 of the arms 23 and the drive-engaged parts 55 are not in contact, or a position of the drive element when the drive engagement parts 25 and the drive-engaged parts 55 are in contact but do not transmit force. In other words, there is a gap between the drive engagement parts 25 and the inner surface of the drive-engaged parts 55 of the arms 23, which allows the contact surfaces 51 to be pressed against the pressed surface 40 due to the pressing of the contact part Q1 of the output element 3 against the output-engaged parts 56.Accordingly, the outward movement of the engagement elements 5 in the radial direction by the arms 23 is not impeded when a torque in the reverse direction is applied to the output element 3. By changing the surface pressure acting on the contact parts between the pressing surfaces 51 and the pressed surface 40, according to the magnitude of the torque applied in the reverse direction to the output element 3, even after the pressing surfaces 51 have come into contact with the pressed surface 40, a locking or partial locking of the output element 3 can be appropriately achieved.

[0067] In the reverse-direction locking clutch 1 according to this embodiment, the drive-side first distance MI1 is larger than the output-side first distance MO1, the drive-side second distance MI2 is smaller than the output-side second distance MO2, and the output contact parts Q1 and Q2 are located closer to the center of rotation C of the output element 3 in the first radial direction D1 than the virtual straight line LH. This adjustment of the dimensional values ​​makes it possible to perform the switching from a locked state or a half-locked state to a locked state or a half-locked state, and vice versa, more smoothly. The reason for this will be explained below with reference to the Fig. 4 to 7 described.

[0068] Fig. Figure 4 is a representation that schematically shows the effect of the opposite-direction locking coupling 1 according to the first embodiment. Fig. Figure 5 is a representation that schematically depicts an effect at the time of unlocking the opposite-direction locking coupling 1 according to the first embodiment. Fig. Figure 4 is a diagram that schematically shows an effect when a reversed entry torque is applied clockwise (CW) at the time of application. Fig. 3 is switched off. Fig. Figure 5 is a diagram that schematically illustrates the effect when a clockwise torque T CW is applied by the drive element 2 to release the locked state in a state where a reverse entry is disengaged due to the engagement between the pressing surfaces 51 and the pressed surface 40 (the locked state of the reverse-direction locking clutch 1). An upward-pointing arrow, which points to the third contact part Q1 in Fig. 5 is applied, is a reverse input torque generated due to a reaction force from the brake disc 14 in the locked state.

[0069] As in Fig. As shown in Figure 4, the engagement elements 5 will likely rotate counterclockwise CCW with respect to the third contact part Q1 if the drive-side first distance MI1 is greater than the output-side first distance MO1 (MI1 > MO1) and a torque (a reverse input) is applied clockwise CW to the output element 3. Since a path r is defined by an alternating long and short dashed line in Fig. As indicated in 4, the pressing surface 51, which is opposite the third contact part Q1 (right side of Fig. 4) with the second reference line L2 located in the second radial direction D2 from the pair of pressing surfaces 51, probably strongly pressed against the pressed surface 40 and wedged into the pressed surface. Accordingly, it is possible to easily lock the engagement elements 5 due to the engagement between the pressing surface 51 and the pressed surface 40 and to easily disengage a clockwise torque CW, which is applied in the opposite direction to the output element 3.

[0070] On the other hand, at the time of unlocking, when the drive-side second distance MI2 is smaller than the output-side second distance MO2 (MI2 < MO2), the third contact part Q1 is arranged closer to the center of rotation C of the output element 3 in the first radial direction D1 than the virtual straight line LH, and a clockwise torque T CW is applied to the drive element 2, as shown in Fig. As shown in Figure 5, the contact parts P5 of the engagement elements 5 will likely rotate clockwise CW with respect to the third contact part Q1. Since the paths of motion r1 and r2 in Fig. As indicated by alternating long and short dashed lines (5), the two pairs of pressing surfaces 51 are not pressed against the pressed surface 40. Consequently, the torque of the drive element 2 does not increase immediately when transitioning from the locked or semi-locked state to the unlocked state. That is, the generation of a peak torque is dampened. Therefore, the transition from the locked or semi-locked state to the unlocked state is smooth and occurs with low torque. Since no peak torque is generated at the time of unlocking, it is unnecessary to increase the maximum output torque of the motor 11, and it is possible to limit the increase in the size and power consumption of the motor 11.

[0071] Fig. Figure 6 is a diagram that schematically illustrates an effect at the time of unlocking a reverse-direction locking coupling 801 according to a comparative example. Similar to Fig. 5 is Fig. Figure 6 shows a schematic representation illustrating the effect when a clockwise torque T CW is applied by the drive element 2 to release the locked state in a state where a reverse entry is disengaged due to the engagement between the pressing surfaces 51 and the pressed surface 40 (the locked state of the reverse-direction locking clutch 1). As in Fig. Figure 6 shows that the drive-side second distance MI2 is smaller than the output-side second distance MO2 (MI2). <MO2), der dritte Kontaktteil Q1 weiter vom Drehzentrum C des Abtriebselements 3 in der ersten radialen Richtung D1 entfernt ist als die virtuelle Gerade LH, und ein Drehmoment T im Uhrzeigersinn CW in das Antriebselement 2 eingetragen wird, werden sich die Eingriffselemente 5 wahrscheinlich im Uhrzeigersinn CW in Bezug auf den dritten Kontaktteil Q1 drehen. Da eine Bewegungsbahn r3 durch eine abwechselnd lang und kurz gestrichelte Linie in Fig. As indicated in 6, the pressing surface 51 (the left contact part P5 in Fig. 6), which is closer to the third contact part Q1 than the first reference line L1 in the second radial direction D2 from the pair of pressing surfaces 51, is probably pressed strongly against the pressed surface 40 and wedged in it. To release the wedging of the pressing surface 51 in the pressed surface 40, the torque of the drive element 2 increases immediately at the moment of switching from the locked or semi-locked state to the unlocked state. That is, a peak torque is generated in a simple way during unlocking.

[0072] Accordingly, by comparing the configuration according to this embodiment, which is in Fig. 5 is shown, and the configuration according to the comparison example shown in Fig. Figure 6 shows that the generation of a peak torque as described above is dampened with the configuration according to this embodiment, in which the drive-side second distance MI2 is smaller than the output-side second distance MO2 (MI2 < MO2) and the third contact part Q1 is arranged closer to the center of rotation C of the output element 3 in the first radial direction D1 than the virtual straight line LH. Accordingly, it is possible to improve the unlocking performance compared to the comparison example if a clockwise torque T CW is applied to the drive element 2 to release the locked state.

[0073] Fig. Figure 7 is a diagram that schematically illustrates an effect at the time of unlocking a reverse-direction locking coupling 901 according to another comparative example. Similar to Fig. 5 is Fig. 7 a representation which schematically illustrates an effect when a clockwise torque T CW is applied by the drive element 2 to release the locked state in a state in which a reverse application is interrupted due to the engagement between the pressing surfaces 51 and the pressed surface 40 (the locked state of the counter-directional locking clutch 1).

[0074] The differences between the reverse-direction locking coupling 1 according to this in Fig. 5 embodiment shown and the opposite-direction locking coupling 901 according to the in Fig. The comparison example shown in Figure 7 and its functional advantages are described below. As indicated by a downward arrow in the Fig. 5 and Fig. As indicated in Figure 7, the engagement elements 5 likely rotate clockwise when a clockwise torque CW is applied to the drive element 2 in the locked state. At this point, in this Fig. In the embodiment shown in Figure 5, if the drive torque is defined as T and a distance in the second radial direction D2 from the first reference line L1 to the second contact part P2 is defined as A, a force F1 acting on the engagement element 5 at the second contact part P2 can be expressed by F1 = T / A. Similarly, as in Fig. Figure 7 shows that a force F2 acting on the engagement element 5 at the second contact part P11 can be expressed by F2 = T / B, where the drive torque is defined as T and a distance D2 in the second radial direction from the first reference line L1 to the second contact part P2 is defined as B. Here, A < B is satisfied.

[0075] Accordingly, the distance A in the second radial direction D2 from the first reference line L1 to the second contact part P2 increases if it is relatively small (see Fig. 5), the load acting on the second contact part P2 when the same torque T is applied, compared to a case where the distance B in the second radial direction D2 from the first reference line L1 to the second contact part P11 is relatively large (see Fig. 7) (F1 > F2). Accordingly, in the case of the Fig. In the configuration shown in Figure 5, this embodiment allows for a reduction in the torque required to switch from the locked or half-locked state to the unlocked state, since the drive-side second distance MI2 is smaller than the drive-side first distance MI1. Consequently, with this embodiment's configuration, in which the contact part (the second contact part P2) is positioned closer to the first reference line L1 than the first contact part P1 in the clockwise direction CW, which is the direction of rotation of the drive element 2 at the time of unlocking, the unlocking performance is improved compared to the comparative example. (How it works and its advantages)

[0076] In the reverse-direction locking clutch 1 according to this embodiment, the distance in the second radial direction D2 between the first contact part P1 and the center of rotation of the drive element 2 (the drive-side first distance MI1) is greater than the distance in the second radial direction D2 between the output contact part Q1 and the center of rotation of the drive element 2 (the output-side first distance MO1). Accordingly, the engagement elements 5 are likely to rotate counterclockwise with respect to the output contact part Q1 when the torque CW (a reverse input) is applied clockwise to the output element 3. As a result, a contact surface 51 (opposite the output contact part Q1 with the first reference line L1 between them in the second direction) is likely to be strongly pressed against the pressed surface 40 by a pair of contact surfaces 51 and wedged in the pressed surface 40.Accordingly, it is possible to effectively interrupt a reverse entry in the second direction of rotation and improve the locking performance.

[0077] The distance in the second radial direction D2 between the second contact part P2 and the center of rotation of the drive element 2 (the drive-side second distance MI2) is smaller than the distance in the second radial direction D2 between the output contact part Q2 and the center of rotation of the drive element 2 (the output-side second distance MO2). Accordingly, it is likely that the engagement elements 5 will rotate clockwise with respect to the output contact part Q1 when a clockwise torque CW is applied to the output element 2. That is, the pair of pressing surfaces 51 will be pressed to disengage from the pressed surface 40. As a result, the peak torque does not increase immediately when switching from the locked or half-locked state to the released locking state, and a smooth transition from the locked or half-locked state to the released locking state is possible.Since the pair of pressing surfaces 51 is not pressed against the pressed surface 40, it is possible to efficiently transmit the torque in the second direction of rotation from the drive element 2 to the engagement elements 5 and the output element 3.

[0078] Accordingly, it is particularly possible when the directions of rotation of the torque applied to the output element 3 and the drive element 2 are the same (clockwise in this embodiment), to effectively interrupt a reverse application from the output element 3 and to transmit an efficient torque from the drive element 2.

[0079] This makes it possible to provide a reverse-direction locking clutch (1) which, compared to the prior art, can improve both the locking performance of a reverse input and the efficiency of the torque transmission of a forward input.

[0080] The distances in the second radial direction D2 of the third contact part Q1 and the fourth contact part Q2 of the output element 3 from the first reference line L1 are set to be equal. The distance MI1 in the second radial direction D2 between the first contact part P1 and the first reference line L1 and the distance MI2 in the second radial direction D2 between the second contact part P2 and the first reference line L1 are set to be different.In this way, it is possible to set the distance MI1 between the first contact part P1 and the first reference line L1 to be greater than the distance MO1 between the output contact part Q1 and the first reference line L1, and to set the distance MI2 between the second contact part P2 and the first reference line L1 to be smaller than the distance MO2 between the output contact part Q2 and the first reference line L1, by adjusting the distances of the first contact part P1 and the second contact part P2 from the first reference line L1 so that they are different from each other. Accordingly, even if the shape of the output engagement part 35 is set to a shape that is horizontally symmetrical and vertically symmetrical, it is possible to effectively cut off a reverse input from the output element 3 and to efficiently transmit a torque from the drive element 2.

[0081] The output contact part is located closer to the center of rotation C of the output element 3 in the first radial direction D1 than the virtual line LH. Accordingly, compared to a case where the output contact parts Q1 and Q2 are located further from the center of rotation C of the output element 3 in the first radial direction D1 than the virtual line LH, it is possible to press the pressing surfaces 51 in such a way that they are more easily separated from the pressed surface 40 when a forward clockwise input CW is applied by the drive element 2. Consequently, it is possible to limit the increase in peak torque when a forward input is applied to the drive element 2 and to achieve a smooth transition from the locked or semi-locked state to the unlocked state.Since it is less likely that the pair of pressing surfaces 51 will be pressed against the pressed surface 40, it is possible to transmit an efficient clockwise torque CW from the drive element 2.

[0082] The direction of rotation of the torque applied in the reverse direction to the output element 3 is the same as the second direction of rotation (clockwise, CW). Accordingly, it is possible to achieve the aforementioned functional advantages by effectively interrupting the reverse input from the output element 3 and efficiently transmitting the torque from the input element 2. Consequently, particularly when the directions of rotation of the torque input to both the output element 3 and the input element 2 are clockwise, CW, it is possible to effectively improve the blocking performance of a reverse input and the efficiency of the torque transmission of a forward input compared to the prior art.

[0083] In the reverse-direction locking system 10 according to this embodiment, the reverse-direction locking system 10 comprises the reverse-direction locking coupling 1 and the ball screw mechanism 12. Here, the ball screw mechanism 12 comprises the ball screw 15, which is a rotating component, and the nut 16, which is a linear motion component, and the nut 16 moves linearly with the rotation of the ball screw 15. However, if the reversing efficiency of the ball screw mechanism 12 is high, the ball screw 15 may rotate at the time the nut 16 is pressed. By combining the ball screw mechanism 12 and the reverse-direction locking coupling 1, it is therefore possible to restrict the rotation of the ball screw 15 and the movement of the nut 16, which is unwanted even when using the ball screw mechanism 12 with high reversing efficiency.

[0084] Accordingly, it is possible to provide a high-performance reverse-direction locking system 10, which includes the reverse-direction locking coupling 1. This coupling can improve both the locking performance of a reverse entry and the torque transmission efficiency of a forward entry compared to the prior art. By combining the ball screw mechanism 12 and the reverse-direction locking coupling 1, it is possible to use the ball screw mechanism 12 more effectively and to improve the versatility of a system that uses the ball screw mechanism 12.

[0085] The reverse-direction locking system 10 comprises the motor 11, which is connected to the drive element 2 of the reverse-direction locking clutch 1, and the brake pad 13, which is connected to the nut 16 of the ball screw mechanism 12 and performs a parking brake application of an electric caliper brake using the locking function of the reverse-direction locking clutch 1. By providing the reverse-direction locking clutch 1 between the motor 11 and the ball screw mechanism 12, it is possible to lock (switch off) the rotation of the ball screw shaft 15 of the ball screw mechanism 12 using the reverse-direction locking clutch 1 when a reaction force acting from the brake disc 14 on the brake pad 13 is transmitted via the ball screw mechanism 12 to the reverse-direction locking clutch 1. Accordingly, it is possible to maintain the position of the brake pad 13 even when the motor 11 is switched off.This makes it possible to reduce the power consumption of the motor 11 compared to an electric caliper brake that does not use the reverse locking clutch 1.

[0086] Accordingly, it is possible to make useful use of the opposite-direction locking system 10 by using the opposite-direction locking system 10 for an electric brake caliper brake with parking brake function. (Second embodiment)

[0087] A second embodiment of the present invention is described below. In the following description, the same components as in the first embodiment are designated with the same reference numerals, and their description is expediently omitted. Specific configurations are not limited to the embodiments and can be modified appropriately without departing from the basic concept of the present invention. Fig. Figure 8 is a sectional view of a counter-directional locking coupling 201 according to the second embodiment. Fig. Figure 8 is a cross-sectional view of the section accordingly. Fig. 3 according to the first embodiment. In the second embodiment, the shape of the arms 23 of a drive element 202 and the shape of the insertion part 32 of an output element 203 differ in the axial direction from those of the first embodiment.

[0088] In the second embodiment, the arms 23 of the drive element 202 are trapezoidal, with one side curved in the axial direction. Specifically, each arm 23 comprises a drive engagement part 25 located on the inside in the radial direction, a curved part 26 located on the outside in the radial direction, and two side parts 27 and 27 that connect the ends of the drive engagement part 25 and the curved part 26. The curved part 26 is arc-shaped around the central axis C.

[0089] The drive engagement part 25 of the drive element 202 comprises a first contact part P201 and a second contact part P202. The first contact part P201 is located near the boundary between one end of the drive engagement part 25 and the side part 27. The first contact part P201 comes into contact with the engagement element 5 when a counterclockwise torque CCW is applied to the drive element 202. The second contact part P202 is located near a boundary between the other end of the drive engagement part 25 and the side part 27. The second contact part P202 comes into contact with the engagement element 5 when a clockwise torque CW is applied to the drive element 202.

[0090] In this embodiment, a distance MI201 in the second radial direction D2 from the first reference line L1 to the first contact part P201 (a drive-side first distance MI201) and a distance MI202 in the second radial direction D2 from the first reference line L1 to the second contact part P202 (a drive-side second distance MI202) are equal (MI201 = MI202).

[0091] The insertion part 32 of the output element 203 has the shape of a parallelogram when viewed in the axial direction. Specifically, the insertion part 32 comprises a pair of output engagement parts 35, which are opposite the pair of engagement elements 5, and a pair of side parts 36, which connect the ends of the output engagement parts 35. The pair of side parts 36 is inclined about the output engagement parts 35. The pair of side parts 36 is parallel to each other.

[0092] Each output engagement part 35 of the output element 203 comprises a third contact part Q201 and a fourth contact part Q202. The third contact part Q201 is located in the same area as the first contact part P201 within the four areas defined by the first reference line L1 and the second reference line L2. The third contact part Q201 is located near the boundary between the output engagement part 35 and the side part 36. The third contact part Q201 comes into contact with the engagement element 5 when a clockwise torque CW is applied to the output element 203. The fourth contact part Q202 is located in the same area as the second contact part P202 within the four areas defined by the first reference line L1 and the second reference line L2. The fourth contact part Q202 is located near the boundary between the output engagement part 35 and the side part 36.The fourth contact part Q202 comes into contact with the engagement element 5 when a counterclockwise torque CCW is applied to the output element 203.

[0093] In this embodiment, a distance MO201 in the second radial direction D2 from the first reference line L1 to the third contact part Q201 (an output-side first distance MO201) is smaller than a distance MO202 in the second radial direction D2 from the first reference line L1 to the fourth contact part Q202 (an output-side second distance MO202) (MO201 < MO202).

[0094] Since the contact parts P201, P202, Q201 and Q202 are provided at the aforementioned positions, the drive-side first distance MI201 in the second embodiment is larger than the output-side first distance MO201, similar to the first embodiment (MI201 > MO201). The drive-side second distance MI202 is smaller than the output-side second distance MO202 (MI202 < MO202).

[0095] In the reverse-direction locking clutch 201 according to the second embodiment, the distances MI201 and MI202 in the second radial direction D2 of the first contact part P201 and the second contact part P202 from the first reference line L1 are equal. The distance MO201 in the second radial direction D2 between the third contact part Q201 and the first reference line L1 and the distance MO202 in the second radial direction D2 between the fourth contact part Q202 and the first reference line L1 are different. Accordingly, even if the shape of the drive engagement part 25 is configured to be horizontally symmetrical, it is possible to set the drive-side first distance MI201 larger than the output-side first distance MO201 and the drive-side second distance MI202 smaller than the output-side second distance MO202.Accordingly, it is possible to achieve the same functional advantages as in the first embodiment, even if the shape of the drive engagement part 25 is configured to be horizontally symmetrical. That is, it is possible to effectively cut off reverse input from the output element 203 and efficiently transmit torque from the drive element 202. Since a configuration different from that of the first embodiment can be used, it is possible to increase the degree of freedom in the shape of the drive engagement part 25 and improve the versatility of the reverse-direction locking clutch 201.

[0096] In Fig. Figure 8 shows a simplified representation of the shape of the engagement elements 5; however, the same shape as for the engagement elements 5 of the first embodiment can be used, for example.

[0097] The technical scope of protection of the present invention is not limited to the aforementioned embodiments and can be modified in various ways without deviating from the basic idea of ​​the present invention.

[0098] In the aforementioned embodiments, the contact parts P1, P2, Q1, and Q2 are arranged, for example, such that the unlocking performance is improved when the drive element 2 rotates in the same direction (clockwise) as the direction in which a reverse drive torque is generated from its directions of rotation, and the present invention is not limited thereto. If, for example, the direction in which a reverse drive torque is generated is counterclockwise (CCW), the positional relationships between the contact parts P1, P2, Q1, and Q2 can be modified such that the unlocking performance is better when the drive element 2 rotates counterclockwise (CCW) than when the drive element 2 rotates clockwise (CW).The contact parts P1, P2, Q1 and Q2 can be arranged such that the unlocking performance is better when the drive element 2 rotates in a direction opposite to the direction in which a reverse torque input is generated.

[0099] The configuration of the ball screw mechanism 12 is not limited to the configurations of the aforementioned embodiments. For example, the nut 16 can be connected to the output element 3 of the reverse-direction locking clutch 1 and the ball screw 15 to the brake pad 13.

[0100] The reverse-direction locking clutch 1 and the reverse-direction locking system 10 according to the aforementioned embodiments can also be used in systems other than the parking brake of an electric brake. For example, the reverse-direction locking clutch 1 and the reverse-direction locking system 10 can be used in a system in which the direction in which a reverse torque is generated is not constant. If the direction of rotation of a reverse torque is constant, as in the case of parking braking, the reverse-direction locking clutch 1 can be designed such that it can be more easily locked in the direction of rotation, thus making it possible to improve both the locking performance and the efficiency of the transmission.Accordingly, the configuration of this embodiment, in which the reverse-direction locking coupling 1 and the ball screw spindle mechanism 12 are combined and used for the parking braking of an electric brake, is better.

[0101] In the aforementioned embodiments, a linkless reverse-direction locking coupling 1 was described in which a link structure is not used as a mechanism for interrupting reverse input, but the present invention is not limited thereto. A link-type reverse-direction locking coupling can also be used in which a known link mechanism is employed as a mechanism for interrupting reverse input.

[0102] The present disclosure may be a combination of the following configurations. (1) Reverse-direction locking coupling, which has: a housing with a pressed surface on an inner circumferential surface; a drive element comprising a drive shaft arranged such that it is coaxial with the pressed surface, and a pair of drive engagement parts arranged such that they are separated from each other in a first radial direction, wherein a central axis of the drive shaft is arranged between them; an output element comprising an output shaft arranged coaxially to the drive shaft and an output engagement part which is provided in the first radial direction between the pair of drive engagement parts; and a pair of engagement elements comprising a pressing surface facing the pressed surface, a drive-engaged part that can engage with the drive-engaged part, and an output-engaged part that can engage with the output-engaged part, wherein the engagement elements are relatively movable in the first radial direction, wherein, when a torque is applied to the drive element, the pair of engagement elements moves to approach each other inwards in the first radial direction based on the engagement between the drive-engaged part and the drive-engaged part, and to transmit the torque to the output element based on the engagement between the driven-engaged part and the driven-engaged part. wherein, when a torque is applied in the reverse direction to the output element, the pair of engagement elements moves in such a way that, due to the engagement between the output-engaged part and the output-engaged part, they are separated from each other in the first radial direction outwards, causing the pressed surface and the pressing surface to engage with each other in a frictional manner, wherein a pair of the drive engagement parts is designed such that they are point-symmetric with respect to a central axis of the drive element when viewed in an axial direction of the drive element, each drive engagement part has: a first contact part that comes into contact with the corresponding engagement element when the torque is applied to the drive element in a first direction of rotation, and a second contact part that comes into contact with the corresponding engagement element when the torque is applied to the drive element in a second direction of rotation that is opposite to the first direction of rotation, wherein the output engagement part has an output contact part which comes into contact with the engagement elements when the torque is applied in the reverse direction to the output element, and wherein a direction that is perpendicular to both the first radial direction and the central axis of the drive element is defined as the second radial direction, a distance in the second radial direction between the first contact part and a center of rotation of the drive element is greater than a distance in the second radial direction between the output contact part and the center of rotation of the drive element, and a distance in the second radial direction between the second contact part and the center of rotation of the drive element is smaller than the distance in the second radial direction between the output contact part and the center of rotation of the drive element. (2) Reverse-direction locking coupling according to (1), wherein the output contact part comprises: a third contact part, which is provided in the same area as the first contact part under four areas defined by a first reference line passing through the central axis of the drive element and parallel to the first radial direction, and a second reference line passing through the central axis of the drive element and parallel to the second radial direction, and a fourth contact part, which is provided in the same area as the second contact part below the four areas defined by the first reference line and the second reference line, wherein the third contact part and the fourth contact part are configured such that the distances in the second radial direction from the center of rotation of the drive element are equal. (3) Reverse-direction locking coupling according to (1) or (2), wherein a distance in the second radial direction between the first contact part and the center of rotation of the drive element is greater than a distance in the second radial direction between the second contact part and the center of rotation of the drive element. (4) Reverse-direction locking coupling according to (1), wherein the output contact part comprises: a third contact part, which is provided in the same area as the first contact part under four areas defined by a first reference line passing through the central axis of the drive element and parallel to the first radial direction, and a second reference line passing through the central axis of the drive element and parallel to the second radial direction, and a fourth contact part, which is provided in the same area as the second contact part among the four areas defined by the first reference line and the second reference line, and wherein the first contact part and the second contact part are designed such that the distances in the second radial direction from the center of rotation of the drive element are equal. (5) Reverse-direction locking clutch according to (1) to (4), wherein the output contact part is arranged closer to a center of rotation of the output element in the first radial direction than a virtual straight line connecting a contact part between a pressing surface of the pair of pressing surfaces and the pressed surface and the center of rotation of the output element in a state in which the torque is reversed into the output element and the pair of pressing surfaces comes into contact with the pressed surface. (6) Reverse-direction locking coupling according to (1) to (5), wherein one direction of rotation of the torque which is applied in reverse to the output element is the same as the second direction of rotation. (7) Counter-directional locking system, which includes: the opposite-direction locking coupling according to (1) to (6); and a ball screw spindle mechanism connected to the output element of the reverse-direction locking coupling. (8) Opposite-direction locking system according to (7), further comprising: a motor connected to the drive element of the reverse-direction locking clutch; and a brake pad connected to a linear motion component of the ball screw mechanism and configured to clamp a brake disc, where a parking brake function of an electric brake caliper brake is performed using a locking function of the opposite-direction locking clutch. REFERENCE MARK LIST 1, 201, 801, 901 Reverse-direction locking coupling 2 Drive unit 3 Output part 4 cases 5 Intervention element 10 Opposite-direction locking system 11 Engine 12 ball screw spindle mechanism 13 Brake pad 14 brake disc 16 Mother (Linear Motion Component) 21 Drive shaft body (drive shaft) 25 Drive engagement part 31 Output shaft body (output shaft) 35 Output engagement part 40 pressed surface 51 Pressing surface 55 Drive-engaged part 56 Output-engaged part CCW direction counterclockwise (first direction of rotation) CW direction clockwise (second direction of rotation) D1 first radial direction D2 second radial direction L2 first reference line L2 second reference line LH virtual straight line MI1, MI201 drive-side first distance MO1, MO201 output side first distance MI2, MI202 drive-side second distance MO2, MO202 output-side second distance P1, P201 first contact part P2, P202 second contact part Q1, Q201 third contact part (output contact part) Q2, Q202 fourth contact part (output contact part) QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] WO 2022 / 168466

[0003]

Claims

[1] Reverse locking coupling, which has: a housing with a pressed surface on an inner circumferential surface; a drive element comprising a drive shaft arranged such that it is coaxial with the pressed surface, and a pair of drive engagement parts arranged such that they are separated from each other in a first radial direction, wherein a central axis of the drive shaft is arranged between them; an output element comprising an output shaft arranged coaxially to the drive shaft and an output engagement part which is provided in the first radial direction between the pair of drive engagement parts; and a pair of engagement elements comprising a pressing surface facing the pressed surface, a drive-engaged part that can engage with the drive-engaged part, and an output-engaged part that can engage with the output-engaged part, wherein the engagement elements are relatively movable in the first radial direction, wherein, when a torque is applied to the drive element, the pair of engagement elements moves to approach each other inwards in the first radial direction based on the engagement between the drive-engaged part and the drive-engaged part, and to transmit the torque to the output element based on the engagement between the driven-engaged part and the driven-engaged part. wherein, when a torque is applied in the reverse direction to the output element, the pair of engagement elements moves in such a way that, due to the engagement between the output-engaged part and the output-engaged part, they are separated from each other in the first radial direction outwards, causing the pressed surface and the pressing surface to engage with each other in a frictional manner, wherein a pair of the drive engagement parts is designed such that they are point-symmetric with respect to a central axis of the drive element when viewed in an axial direction of the drive element, each drive engagement part has: a first contact part that comes into contact with the corresponding engagement element when the torque is applied to the drive element in a first direction of rotation, and a second contact part that comes into contact with the corresponding engagement element when the torque is applied to the drive element in a second direction of rotation that is opposite to the first direction of rotation, wherein the output engagement part has an output contact part which comes into contact with the engagement elements when the torque is applied in the reverse direction to the output element, and wherein a direction that is perpendicular to both the first radial direction and the central axis of the drive element is defined as the second radial direction, a distance in the second radial direction between the first contact part and a center of rotation of the drive element is greater than a distance in the second radial direction between the output contact part and the center of rotation of the drive element, and a distance in the second radial direction between the second contact part and the center of rotation of the drive element is smaller than the distance in the second radial direction between the output contact part and the center of rotation of the drive element. [2] Reverse-direction locking clutch according to claim 1, wherein the output contact part comprises: a third contact part, which is provided in the same area as the first contact part under four areas defined by a first reference line passing through the central axis of the drive element and parallel to the first radial direction, and a second reference line passing through the central axis of the drive element and parallel to the second radial direction, and a fourth contact part which is provided in the same area as the second contact part below the four areas defined by the first reference line and the second reference line, and wherein the third contact part and the fourth contact part are configured such that the distances in the second radial direction from the center of rotation of the drive element are equal. [3] Reverse-direction locking coupling according to claim 1 or 2, wherein a distance in the second radial direction between the first contact part and the center of rotation of the drive element is greater than a distance in the second radial direction between the second contact part and the center of rotation of the drive element. [4] Reverse-direction locking clutch according to one of claims 1 to 3, wherein the output contact part comprises: a third contact part, which is provided in the same area as the first contact part under four areas defined by a first reference line passing through the central axis of the drive element and parallel to the first radial direction, and a second reference line passing through the central axis of the drive element and parallel to the second radial direction, and a fourth contact part, which is provided in the same area as the second contact part among the four areas defined by the first reference line and the second reference line, and wherein the first contact part and the second contact part are designed such that the distances in the second radial direction from the center of rotation of the drive element are equal. [5] Reverse-direction locking clutch according to one of claims 1 to 4, wherein the output contact part is arranged closer to a center of rotation of the output element in the first radial direction than a virtual straight line connecting a contact part between a pressing surface of the pair of pressing surfaces and the pressed surface and the center of rotation of the output element in a state in which the torque is reversed into the output element and the pair of pressing surfaces comes into contact with the pressed surface. [6] Reverse-direction locking coupling according to one of claims 1 to 5, wherein one direction of rotation of the torque, which is applied in reverse to the output element, is the same as the second direction of rotation. [7] Opposing-direction locking system, which features: the opposite-direction locking coupling according to one of claims 1 to 6; and a ball screw spindle mechanism connected to the output element of the reverse-direction locking coupling. [8] Opposite-direction locking system according to claim 7, further comprising: a motor connected to the drive element of the reverse-direction locking clutch; and a brake pad connected to a linear motion component of the ball screw mechanism and configured to clamp a brake disc, where a parking brake function of an electric brake caliper brake is performed using a locking function of the opposite-direction locking clutch.

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