CN113710126A

CN113710126A - Seat inclination angle adjusting device for vehicle

Info

Publication number: CN113710126A
Application number: CN202080030227.4A
Authority: CN
Inventors: 寺口博明; 西浦武史; 星原直明
Original assignee: Toyota Boshoku Corp
Current assignee: Toyota Boshoku Corp
Priority date: 2019-04-25
Filing date: 2020-04-24
Publication date: 2021-11-26
Also published as: JP2020179840A; JP7404935B2

Abstract

A seat reclining device (4) is provided with: a ratchet (10) and a guide (20) which are assembled in a relatively rotatable manner; a pawl (30) capable of restricting relative rotation between the ratchet (10) and the guide (20); and a rotating cam (40) for pushing the pawl (30). The pawl (30) has: an eccentric structure that is pressed and tilted to one side in the rotational direction by a pressing force received from the rotating cam (40); and a first protrusion (35A) that restricts the tilt of the pawl (30) by contact with the opposing guide wall (23).

Description

Seat inclination angle adjusting device for vehicle

Technical Field

The present invention relates to a vehicle seat reclining device. More particularly, the present invention relates to a vehicle seat reclining device for adjusting a reclining angle of a seat back.

Background

Conventionally, as a vehicle seat reclining device, a device including a stepped lock mechanism capable of adjusting a backrest angle of a seat backrest at a constant pitch angle is known (patent document 1). The vehicle seat reclining device is configured as a joint device that connects a seat back to a seat cushion so that a backrest angle can be adjusted. Specifically, the vehicle seat reclining device includes: a ratchet and a guide which are assembled in a manner of being capable of rotating relative to each other and are composed of metal parts in a substantially disc shape; and a lock mechanism for locking relative rotation of the two.

The locking mechanism has the following structure: the plurality of pawls provided in the guide press and engage with inner circumferential teeth formed on an outer circumferential portion of the ratchet by being biased, thereby locking relative rotation between the ratchet and the guide. The pawls are supported by the guides from both sides in the rotational direction and are guided so as to be movable only radially inward and outward.

Documents of the prior art

Patent document 1: international publication No. 2016/129423

Disclosure of Invention

Problems to be solved by the invention

In order to ensure the slidability of each pawl, it is necessary to set a slight clearance in the rotational direction between each pawl and each guide wall of the guide that supports the pawls from both sides in the rotational direction. However, if the clearance is large, the pawls may tilt between the guide walls, and the like, and the posture of the pawls may become unstable (i.e., so-called "rattling"). An object of the present invention is to provide a vehicle seat reclining device that can ensure both the slidability of a pawl and the suppression of rattling.

Means for solving the problems

[1] In a first aspect of the present invention, a vehicle seat reclining device includes:

a ratchet and a guide assembled in an axial direction so as to be rotatable relative to each other;

a pawl supported from both sides in a rotational direction by a pair of guide walls provided on the guide, and engaged with the ratchet by being pushed outward in a radial direction to restrict relative rotation between the ratchet and the guide; and

a cam for pushing the pawl from the inner side to the outer side in the radial direction,

the pawl includes: an eccentric structure that is pressed and inclined to one side in the rotational direction between the pair of guide walls by a pressing force received from the cam; and a first protrusion protruding from one side surface of the pawl in the rotation direction and restricting inclination of the pawl by contact with the guide wall facing the pawl.

According to the first aspect, it is possible to provide a gap in the rotational direction between the pawl and each guide wall, and to restrict the inclination of the pawl in the gap by the contact of the first projection with the guide wall. This can ensure the sliding property of the pawl and suppress the rattling at the same time.

[2] In the second aspect of the present invention, in the above-described first aspect,

the pawl has a second projection that projects from the other side surface in the rotation direction and is held in a posture in which the pawl contacts both of the pair of guide walls by contact with the guide walls that face each other.

According to the second aspect, the pawl can be held in contact with the two guide walls in a state in which the gap in the rotational direction is filled, and thus rattling of the pawl can be more appropriately suppressed.

[3] In the third aspect of the present invention, in the above-described second aspect,

the second projection is located radially outward of the first projection.

According to the third configuration, when the pawl is inclined in the direction of filling the gap between the guide wall and the side surface on the other side close to the outer peripheral side of the meshing portion with the ratchet wheel, with the contact point of the first protrusion and the guide wall as a base point, the second protrusion can be brought into contact with the guide wall at a relatively early stage to restrict the inclination of the pawl.

[4] In a fourth aspect of the present invention, in the above-described second or above-described third aspect,

the pawl includes: a main body surface portion that receives a pressing force from the radially inner side by the cam; and an offset surface portion having a shape that is pushed out from the main body surface portion in an axial direction in a half-blanking shape and arranged in parallel with the cam in the axial direction,

the second protrusion has the following shape: the inclined surface of the second projection extends over at least the entire area of the main body surface portion on the other side surface of the pawl in the rotational direction.

According to the fourth aspect, the structural strength of the second projection can be improved as compared with a structure in which the second projection is partially formed on the side surface on the other side in the rotational direction of the pawl. In addition, the second protrusion can be easily formed.

[5] In a fifth aspect of the present invention, in any one of the above first to fourth aspects,

the reclining device of a vehicle seat includes a plurality of pawls,

a specific one of the plurality of pawls has the first projection.

According to the fifth aspect, rattling of the pawl can be suppressed reasonably.

[6] In a sixth aspect of the present invention, in any one of the above first to fifth aspects,

the first protrusion has the following shape: the inclined surface of the first projection extends over at least the entire area of the main body surface portion on one side surface of the pawl in the rotational direction.

According to the sixth aspect, the structural strength of the first projection can be improved as compared with a configuration in which the first projection is partially formed on the side surface on one side in the rotation direction of the pawl. In addition, the first protrusion can be easily formed.

[7] In a seventh aspect of the present invention, a vehicle seat reclining device includes:

a pawl supported from both sides in a rotational direction by a pair of guide walls provided on the guide, and engaged with the ratchet by being pushed outward in a radial direction to restrict relative rotation between the ratchet and the guide;

a cam for pushing the pawl from the inner side to the outer side in the radial direction;

an eccentric structure that inclines the pawl by pressing the pawl between the pair of guide walls in the rotational direction by a pressing force received from the cam; and

and a first protrusion protruding from the guide wall facing a side surface of the pawl on one side in the rotational direction, and restricting inclination of the pawl by contact with the pawl.

According to the seventh aspect, it is possible to provide a gap in the rotational direction between the pawl and each guide wall, and to restrict the inclination of the pawl in the gap by the contact of the first protrusion with the pawl. This can ensure the sliding property of the pawl and suppress the rattling at the same time.

[8] In an eighth aspect of the present invention, in the seventh aspect described above,

the vehicle seat reclining device includes a second protrusion that protrudes from the guide wall facing the other side surface of the pawl in the rotational direction, and that is configured to be brought into contact with both of the pair of guide walls by being in contact with the pawl to regulate the tilt of the pawl.

According to the eighth aspect, the pawl can be brought into contact with the two guide walls to keep the gap in the rotational direction in a filled state, and thus rattling of the pawl can be more appropriately suppressed.

[9] In a ninth aspect of the present invention, in the eighth aspect described above,

the second protrusion has the following shape: the inclined surface of the second projection extends over the entire area of the side surface of the guide wall facing the pawl.

According to the ninth aspect described above, the structural strength of the second projection can be improved as compared with a structure in which the second projection is partially formed on the guide wall. In addition, the second protrusion can be easily formed.

[10] In a tenth aspect of the present invention, in any one of the seventh to ninth aspects described above,

the first protrusion has the following shape: the inclined surface of the first projection extends over the entire area of the side surface of the guide wall facing the pawl.

According to the tenth aspect, the structural strength of the first projection can be improved as compared with a structure in which the first projection is partially formed on the guide wall. In addition, the first protrusion can be easily formed.

Drawings

Fig. 1 is a perspective view showing a schematic configuration of a vehicle seat to which a vehicle seat reclining device according to a first embodiment is applied.

Fig. 2 is an exploded perspective view of a main portion of fig. 1.

Fig. 3 is an exploded perspective view of fig. 2 viewed from the opposite side.

Fig. 4 is an exploded perspective view of the reclining device of a vehicle seat.

Fig. 5 is an exploded perspective view of fig. 4 viewed from the opposite side.

Fig. 6 is an outside view of the seat reclining device for a vehicle.

Fig. 7 is an inside view of the seat reclining device for a vehicle.

Fig. 8 is a front side view of the seat reclining device for a vehicle.

Fig. 9 is a cross-sectional view taken along line IX-IX in fig. 1.

Fig. 10 is a cross-sectional view taken along line X-X in fig. 8 showing a locked state of the reclining device of a vehicle seat.

Fig. 11 is a cross-sectional view corresponding to fig. 10 showing an unlocked state of the seat reclining device for a vehicle.

Fig. 12 is a sectional view showing a state where the ratchet rotates from fig. 11 to a free region.

Fig. 13 is a sectional view showing a state where the locking operation of the reclining device of a vehicle seat is prevented from fig. 12.

Fig. 14 is a sectional view showing a state where the ratchet wheel is rotated to the start position of the lock region.

Fig. 15 is an enlarged view of the XV portion in fig. 9.

Fig. 16 is a cross-sectional view showing a state in which the rotating cam is pressed against the guide wall by an urging force.

Fig. 17 is a cross-sectional view showing changes in the locking operation of each pawl associated with changes in the rotational position of the ratchet wheel, which is divided into cases (a) to (d).

Fig. 18 is a schematic diagram showing a positional relationship between the multiplying protrusions of the pawls and the protruding portions of the ratchet in fig. 17(a) to (d).

Fig. 19 is an outside view of each pawl.

Fig. 20 is an inside view of each pawl.

Fig. 21 is a side view showing the angle adjustment range of the seat back.

Fig. 22 is an inside view showing a state of the reclining device of a vehicle seat in fig. 21.

Fig. 23 is a sectional view taken along line XXIII-XXIII in fig. 22.

Fig. 24 is a sectional view taken along line XXIV-XXIV in fig. 22.

Fig. 25 is a side view showing a state in which the seat back is tilted backward from the torso angle.

Fig. 26 is an inside view showing a state of the reclining device of a vehicle seat in fig. 25.

Fig. 27 is a sectional view taken along line XXVII-XXVII in fig. 26.

Fig. 28 is a sectional view taken along line XXVIII-XXVIII in fig. 26.

Fig. 29 is a side view showing a state in which the seat back is tilted forward from the torso angle.

Fig. 30 is an inside view showing a state of the reclining device of a vehicle seat in fig. 29.

FIG. 31 is a cross-sectional view taken along line XXXI-XXXI in FIG. 30.

FIG. 32 is a cross-sectional view taken along line XXXII-XXXII in FIG. 30.

Fig. 33 is an enlarged view of XXXIII in fig. 14.

Fig. 34 is an enlarged view of XXXIV portion in fig. 10 showing an engagement state of the specific pawl with the ratchet gear in an enlarged manner.

Fig. 35 is a cross-sectional view corresponding to fig. 34 showing an engaged state in which the first projection abuts against the guide wall.

Fig. 36 is a sectional view showing a state where the ratchet rotates counterclockwise from fig. 35 to a position where the second projection abuts against the guide wall.

Fig. 37 is a cross-sectional view corresponding to fig. 34 showing the configuration of the vehicle seat reclining device according to the second embodiment.

Fig. 38 is a cross-sectional view corresponding to fig. 34 showing the configuration of the vehicle seat reclining device according to the third embodiment.

Fig. 39 is a cross-sectional view corresponding to fig. 34 showing the configuration of a seat reclining device for a vehicle according to a fourth embodiment.

Fig. 40 is a cross-sectional view corresponding to fig. 34, showing the configuration of a seat reclining device for a vehicle according to a fifth embodiment.

Detailed Description

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

(first embodiment)

General Structure of seat reclining device 4 (seat reclining device for vehicle)

First, the structure of the seat reclining device 4 according to the first embodiment of the present invention will be described with reference to fig. 1 to 36. In the following description, the terms "front, rear, up, down, left, right, and the like" refer to the respective directions shown in the respective drawings. In addition, the term "seat width direction" refers to the lateral direction of the seat 1 described later.

As shown in fig. 1, the seat reclining device 4 according to the present embodiment is applied to a seat 1 constituting a right seat of an automobile. The seat reclining device 4 is configured as a reclining mechanism that connects a seat back 2, which constitutes a backrest portion of the seat 1, to a seat cushion 3, which constitutes a sitting portion, in a state in which a backrest angle can be adjusted. Specifically, the seat reclining device 4 is provided in a pair of left and right between the seat back 2 and the seat cushion 3. Each seat reclining device 4 has the following structure: the backrest angle of the seat back 2 is fixed or released by switching to the locked and unlocked states at once.

Specifically, as shown in fig. 2 to 3, the seat reclining devices 4 are respectively interposed between the lower end portions of the side frames 2F and the reclining plates 3F, and are connected to each other in a state of being rotatable or locked relative to each other around the same axis, the side frames 2F constituting the left and right side frames of the seat back 2, and the reclining plates 3F being positioned on the outer sides of the side frames 2F in the seat width direction and connected to the rear end portions of the left and right side frames of the seat cushion 3.

As shown in fig. 1, the seat reclining device 4 is kept in a locked state in which the backrest angle of the seat back 2 is fixed when flat. The seat reclining device 4 is unlocked at the same time by a user's operation of pulling up a reclining lever 5 (circled number 1 in fig. 1) provided at a side portion of the seat cushion 3 on the vehicle outer side (right side). Thereby, the seat reclining device 4 is switched to the unlocked state in which the backrest angle of the seat back 2 can be adjusted in the seat front-rear direction. The seat reclining apparatus 4 is retracted by the operation of the reclining lever 5 and returned to the locked state again by an acting force.

Return springs 6 are respectively hooked between the left and right side frames 2F of the seat back 2 and the respective reclining plates 3F located on the outer sides thereof, and the return springs 6 apply spring biasing forces to the seat back 2 in directions to tilt forward and rotate. By the rotational urging force of these return springs 6, the seat back 2 is lifted to a position abutting against the back of the seated occupant by releasing the fixed state of the back angle by the seat reclining device 4.

The seat back 2 is adapted to the action of tilting the back of the seated occupant forward and backward, and the back angle thereof is freely adjusted forward and backward (circled number 2 in fig. 1). In this way, the backrest angle of the seat back 2 can be easily adjusted by setting the return spring 6 that applies a biasing force in the forward rotational direction to the seat back 2. Specifically, as shown in fig. 21, the seat back 2 is rotatable in the seat front-rear direction within a rotation region of approximately 180 degrees between a forwardly tilted position Pa overlapping the upper surface of the seat cushion 3 and a rearwardly tilted position Pc tilted rearward in a substantially horizontal shape.

The structure for locking the seat back 2 at the forward inclined position Pa is configured as follows: each locking plate 2Fc coupled to an outer side surface portion of each side frame 2F of the seatback 2 abuts against and is locked to each front stopper 3Fc formed to protrude from a front edge portion of each reclining plate 3F. Further, the structure for locking the seat back 2 at the rearward inclined position Pc is configured as follows: each locking plate 2Fc coupled to the outer side surface portion of each side frame 2F of the seat back 2 abuts against and is locked to each rear stopper 3Fd formed to protrude from the rear edge portion of each reclining plate 3F.

Here, a rotation region of approximately 90 degrees from the primary lock position Pb in which the backrest angle of the seat back 2 is raised substantially vertically to the rearward inclined position Pc in the rotation region of the seat back 2 described above is set as a "lock region a 1", and the lock region a1 is a region in which the backrest angle of the seat back 2 is returned to the fixed state by releasing the pulling-up operation of the reclining lever 5. A rotation region of about 90 degrees from the primary lock position Pb to the forward tilting position Pa of the backrest angle of the seat back 2 is set as a "free region a 2", and the free region a2 is a region in which the angle of the seat back 2 is not fixed and the released state (the state in which the lock is disabled) is maintained even when the pulling-up operation of the reclining lever 5 is released.

The lock area a1 and the free area a2 are set by functions provided in the seat reclining device 4, which will be described later. By setting the free area a2, the seat back 2 can be automatically tilted to the forward tilt position Pa even if the operation of the reclining lever 5 is not continued from the position after the reclining lever 5 is operated to tilt forward to the position entering the free area a2 in a state where a person is not seated on the seat 1.

Specifically, as shown in fig. 2 to 3, the seat reclining device 4 includes: a ratchet 10 (see fig. 2) integrally coupled to an outer side surface portion of the side frame 2F on each side of the seat back 2; and guides 20 (see fig. 3) integrally coupled to inner side surfaces of the respective inclination adjustment plates 3F. The seat reclining device 4 has the following structure: the backrest angle of the seat back 2 is fixed or released by switching to lock or release the relative rotation of the ratchet 10 and the guide 20 with respect to each other.

Structure of each part of seat reclining device 4

The configuration of each part of the pair of right and left seat reclining devices 4 will be described in detail below. The seat reclining devices 4 have the same structure, which is bilaterally symmetrical to each other. Therefore, the structure of the seat reclining device 4 disposed on the vehicle outer side (right side) shown in fig. 2 to 3 will be described in detail below, in place of the seat reclining devices 4.

As shown in fig. 4 to 5, the seat reclining device 4 includes: a ratchet 10 and a guide 20 of a substantially circular plate shape assembled to each other in an axial direction; three pawls 30 assembled between the ratchet 10 and the guide 20; and a rotating cam 40 for moving the pawls 30 radially inward and outward. Further, the seat reclining device 4 includes: a lock spring 50 (coil spring) that biases the rotary cam 40 in a rotational direction in which the guide 20 is locked; and a substantially cylindrical outer peripheral ring 60 mounted astride between the ratchet 10 and the outer peripheral portion of the guide 20.

The outer peripheral ring 60 functions as a holding member that holds the ratchet 10 and the guide 20 in a state of being assembled to each other in the axial direction. Here, the rotating cam 40 corresponds to a "cam" of the present invention. The ratchet 10, the guide 20, the three pawls 30, and the rotating cam 40 are hardened by quenching after press forming, thereby improving the structural strength.

About ratchet 10

As shown in fig. 4, the ratchet 10 has the following structure: a metal plate-like member is cut into a substantially circular plate-like shape, and each part is processed so as to be pushed out in a half-blanking shape in a plate thickness direction (axial direction). Specifically, the ratchet 10 has the following structure: a stepped cylindrical portion protruding in two steps in an axial direction, which is an assembling direction of the disc main body 11 to the guide 20, is formed by half-punching and pushing out the outer peripheral edge portion of the disc main body 11.

The cylindrical portion on the outer peripheral side of the stepped cylindrical portion is formed as a cylindrical portion 12 having internal teeth 12A formed over the entire inner peripheral surface. The inner cylindrical portion is formed as an intermediate cylindrical portion 13 having a shorter axial projection length than the cylindrical portion 12. The internal teeth 12A of the cylindrical portion 12 are formed in a tooth surface shape that allows each external tooth 31 formed on an outer circumferential surface portion of each pawl 30 described later to mesh with each other from the radially inner side. Specifically, the internal teeth 12A are formed in a shape in which the tooth surfaces are arranged at equal intervals at intervals of 2 degrees in the rotational direction.

Further, the inner circumferential surface portion of the intermediate cylindrical portion 13 is formed with: three regions (a first region 13A, a second region 13B, and a third region 13C) in which the inner diameter size and the length in the rotational direction from the rotational center C of the ratchet 10 are set, respectively; and a first convex portion 13D and a second convex portion 13E protruding inward in the radial direction at the boundary portion between the regions.

The first region 13A, the second region 13B, and the third region 13C are each formed in an inner peripheral surface shape curved in an arc shape drawn around the rotation center C of the ratchet 10. Specifically, as shown in fig. 10, the first region 13A and the third region 13C are each formed in an inner peripheral surface shape having the same diameter and an inner diameter size one turn larger than that of the second region 13B.

As shown in fig. 10, 17(a) and 18(a), when the rotation angle of the ratchet 10 is such that the first region 13A overlaps with the main pawl P1, which is one of the three pawls 30 described later, in the rotation direction, the first region 13A constitutes a lock region a1 that allows meshing of the main pawl P1 with respect to the internal teeth 12A. At this time, the second region 13B and the third region 13C are disposed so as to overlap the remaining two sub pawls P2 in the rotational direction, and are formed as escape regions A3 that allow the engagement of the sub pawls P2 with the internal teeth 12A. Here, the primary pawl P1 corresponds to the "special pawl" of the present invention.

On the other hand, as shown in fig. 12, when the rotation angle of the ratchet 10 is such that the second region 13B overlaps with the main pawl P1 in the rotation direction, as shown in fig. 13, 17(B) and 18(B), the second region 13B constitutes a free region a2 in which the engagement of the inner teeth 12A of the main pawl P1 is blocked by being multiplied by the inner circumferential surface. At this time, the third region 13C and the first region 13A are respectively disposed to overlap the remaining two sub pawls P2 in the rotational direction, and are formed as an escape region A3 for escaping the movement of the sub pawls P2.

That is, the intermediate cylindrical portion 13 of the ratchet 10 has the following configuration: the locking action of the primary pawl P1 is permitted in the first region 13A thereof as shown in fig. 10, and the locking action of the primary pawl P1 is prevented in the second region 13B thereof as shown in fig. 12 to 13. As shown in fig. 10, when the locking operation of the primary pawl P1 is permitted, each pawl 30 also permits the locking operation of the remaining two secondary pawls P2. As shown in fig. 12 to 13, each of the pawls 30 prevents the locking operation of the main pawl P1, thereby preventing the locking operation of the remaining two sub pawls P2.

In this way, the intermediate cylindrical portion 13 of the ratchet 10 controls the lock permission/prevention of the primary pawl P1 through the first region 13A and the second region 13B. When the first region 13A functions as the lock region a1 (see fig. 10), the other two regions (the second region 13B and the third region 13C) each function as an escape region A3 that allows the locking operation of the remaining two sub pawls P2. When the second region 13B functions as the free region a2 (see fig. 13), the other two regions (the first region 13A and the third region 13C) each function as an escape region A3 for escaping the movement of the remaining two sub pawls P2.

As shown in fig. 17(c) and 18(c), the first convex portion 13D and the second convex portion 13E are formed at the following positions: when the main pawl P1 moves from the lock region a1 (the first region 13A) to the free region a2 (the second region 13B) by the rotation of the ratchet 10, the first convex portion 13D and the second convex portion 13E allow the other two sub pawls P2 to simultaneously abut in the rotation direction, respectively, in the case where the pushing-out to the outside in the radius direction is incomplete and abuts against the step between the first region 13A and the second region 13B in the rotation direction. By simultaneously abutting the sub pawls P2, the load applied when the main pawl P1 abuts against the step can be distributed to the other two sub pawls P2.

Specifically, the first convex portion 13D and the second convex portion 13E are formed at the following positions: when the multiplied protrusions 34 of the primary pawl P1 abut against the steps between the first region 13A and the second region 13B in the rotational direction by the rotation of the ratchet 10, the first convex portion 13D and the second convex portion 13E abut against the multiplied protrusions 34 of the remaining two secondary pawls P2, respectively, in the same rotational direction. The structure of each of the multiplying projections 34 will be described later in detail.

As shown in fig. 14, 17(d) and 18(d), the second protrusion 13E is formed so as to protrude from the end of the lock region a1 (first region 13A) on the rotation direction side, that is, from the end of the lock region a1 on the side opposite to the side adjacent to the free region a2 (second region 13B). The second convex portion 13E is formed at the following position: when the seat back 2 falls to the backward falling position Pc, which is the starting end of the lock region a1, as shown in fig. 21, the arrangement of the second convex portion 13E in the rotational direction can be overlapped with the riding projection 34 of the main pawl P1, as shown in fig. 14, 17(d), and 18 (d).

The reason for this is as follows. That is, when the seat back 2 is tilted to the rearward tilting position Pc as shown in fig. 21, the locking plate 2Fc abuts against and is locked to the rear stopper 3Fd of the reclining plate 3F. At this time, depending on the installation of the seat reclining device 4 and its peripheral components, if the riding projection 34 of the primary pawl P1 shown in fig. 14 abuts against the second convex portion 13E in the rotational direction before the aforementioned catch plate 2Fc abuts against the rear side stopper 3Fd of the reclining plate 3F, a large load is applied to the seat reclining device 4. Therefore, in order not to cause such a situation, an escape recess 13E1 is formed in the second convex portion 13E, and this escape recess 13E1 is used to avoid abutment of the second convex portion 13E with the riding-up protrusion 34 of the main pawl P1 in the rotational direction.

As shown in fig. 33, the relief recess 13E1 is formed by partially removing a corner portion of the second convex portion 13E on the clockwise direction side in the figure to have a substantially rectangular shape. Even if the seat back 2 falls toward the rearward falling position Pc due to dimensional variations caused by the above-described attachment, as shown in fig. 21, and the locking plate 2Fc abuts against and is locked by the rear stopper 3Fd of the reclining plate 3F, the riding projection 34 of the primary pawl P1 is arranged to overlap the second convex portion 13E in the rotational direction as shown in fig. 33, and the riding recess 13E1 receives the riding projection 34 so that the riding projection 34 does not abut against the second convex portion 13E in the rotational direction. Specifically, the escape recess 13E1 receives the riding projection 34 in a state where the riding projection 34 and the counterclockwise side surface of the escape recess 13E1 have a gap Y in the rotational direction.

When the riding-up projection 34 of the main pawl P1 that has entered the inside of the escape recess 13E1 is pushed outward in the radial direction, the riding-up projection 34 rides up the inner peripheral surface of the escape recess 13E1, thereby preventing the main pawl P1 from meshing with the internal teeth 12A of the ratchet 10. Thereby, the locking of the main pawl P1 is prevented at a position (a rotational position beyond the locking region a1) where the riding-up projection 34 of the main pawl P1 enters the escape recess 13E 1.

As shown in fig. 4 to 5, a through hole 11A penetrating in a circular hole shape is formed in the center portion (position on the rotation center C) of the disk body 11 of the ratchet 10. An operation pin 5A inserted into a center portion (a position on the rotation center C) of a rotary cam 40 described later is inserted into the through hole 11A from the outside in the axial direction in a rotatable state.

As shown in fig. 3, the ratchet 10 is attached such that the outer side surface of the circular plate body 11 abuts against the outer side surface of the side frame 2F of the seat back 2, and the abutting portions are welded to be integrally coupled to the side frame 2F of the seat back 2. Specifically, the ratchet 10 is set in the following state: three tenon teeth 14 formed to protrude on the outer side surface of the disk main body 11 are fitted into corresponding three fitting holes 2Fa formed in the side frames 2F of the seat back 2, whereby the outer side surface of the disk main body 11 abuts on the outer side surfaces of the side frames 2F.

The peripheral regions (the joining regions a4) of the respective fitting portions of the ratchet 10 are joined to the side frames 2F by laser welding. As shown in fig. 5, one tenon tooth 14 is formed in each of the first, second, and

third regions

13A, 13B, and 13C of the intermediate cylindrical portion 13 in the rotational direction. Each tenon tooth 14 is formed so as to be curved in a circular arc shape curved around the rotation center C of the ratchet 10.

The outer region in the radial direction of each tenon tooth 14 on the outer side surface of the disk main body 11 of the ratchet 10 is a joining region a4 which is brought into surface contact with the side frame 2F and laser-welded. As shown in fig. 7, each bonding area a4 has the following structure: due to the uneven shape of the intermediate cylindrical portion 13 formed at the outer peripheral edge portions thereof, the joining region a4 of each portion where the first region 13A and the third region 13C are located has an expanded surface portion 11B having a larger size in the radial direction than the joining region a4 of the portion where the second region 13B is located.

Namely, the following shape is formed: the first region 13A and the third region 13C formed in the intermediate cylindrical portion 13 are formed so as to have radially larger diameters than the second region 13B as described above. Thus, the following structure is achieved: the joining region a4 of each portion where the first region 13A and the third region 13C are formed has a radial dimension larger than that of the joining region a4 of each portion where the second region 13B is formed. According to the above configuration, in the outer side surface of the circular plate main body 11 of the ratchet 10, the two joining regions a4 having the expanded surface portions 11B of the respective portions where the first region 13A and the third region 13C are formed are firmly welded in a state of being abutted more widely outward in the radial direction with respect to the side frame 2F.

The ratchet 10 is welded to the side frame 2F by joining a weld so as to surround each tenon tooth 14 in a C-shape from the outside in the radial direction to both side regions in the rotational direction. As shown in fig. 3, the side frame 2F has a through hole 2Fb formed in a circular hole shape at a position axially opposite to the through hole 11A formed in the center portion (position on the rotation center C) of the ratchet 10. The operating pin 5A inserted through the through hole 11A of the ratchet 10 axially penetrates through the through hole 2 Fb.

Guide 20

As shown in fig. 5, the guide 20 has the following structure: one metal plate-like member is cut into a substantially disk-like shape having an outer diameter one turn larger than the ratchet 10, and each part is processed so as to be pushed out in a half-blanking shape in a plate thickness direction (axial direction). Specifically, the guide 20 has the following structure: a cylindrical portion 22 is formed by half-punching and pushing out the outer peripheral edge portion of the disk main body 21, and the cylindrical portion 22 protrudes cylindrically in an axial direction which is an assembling direction of the ratchet 10.

The cylindrical portion 22 is formed so that the inner diameter dimension thereof is slightly larger than the outer diameter dimension of the cylindrical portion 12 of the ratchet 10. Specifically, the cylindrical portion 22 has the following configuration: the thickness in the radial direction is formed thinner than the thickness of an outer peripheral ring 60 (see fig. 15) described later. More specifically, the cylindrical portion 22 has the following configuration: the thickness in the radial direction is reduced to such an extent that the outer peripheral surface thereof is located radially inward of the outer peripheral surface of the step 63 of the outer peripheral ring 60 described later. As shown in fig. 9, the guide 20 is installed so that the cylindrical portion 12 of the ratchet 10 is loosely fitted in the cylindrical portion 22 of the guide 20 in the axial direction.

Thus, the guide 20 and the ratchet 10 are assembled in a state in which the respective

cylindrical portions

22 and 12 are loosely fitted to each other in the radial direction, and are supported by each other in the inner and outer directions so as to be rotatable relative to each other. Further, the guide 20 is assembled by attaching an outer peripheral ring 60, which will be described later, between the cylindrical portion 22 thereof and the cylindrical portion 12 of the ratchet 10 so as to straddle from the outer peripheral side, and by this outer peripheral ring 60 in a state of being axially separated from the ratchet 10 (see fig. 2 to 3 and 6 to 9).

As shown in fig. 5, guide walls 23 are formed by half-blanking on the inner surface of the disk body 21 of the guide 20 at three positions in the rotational direction, and the guide walls 23 project in a substantially fan shape in the axial direction that is the assembling direction of the ratchet 10. These guide walls 23 are in the following shape: outer circumferential surfaces on outer sides in the radial direction thereof are curved so as to describe an arc on the same circumference described around the rotation center C of the guide 20. Each guide wall 23 is installed in a state of being loosely fitted into the cylindrical portion 12 of the ratchet 10 assembled in the cylindrical portion 22 of the guide 20.

By forming the guide walls 23, concave pawl receiving grooves 24A are formed in the inner surface of the disc main body 21 of the guide 20 in the area between the guide walls 23 in the rotational direction, and the pawl receiving grooves 24A allow three pawls 30 to be slidably mounted one by one only radially inward and outward. In a central region on the inner surface of the disk main body 21 surrounded by the guide walls 23, a cam receiving groove 24B is formed so as to be able to axially rotate a rotary cam 40 described later.

As shown in fig. 10 to 11, each guide wall 23 can support each corresponding pawl 30 mounted in each pawl housing groove 24A from both sides in the rotational direction by each regulating surface 23A which faces both side surfaces in the rotational direction in each pawl housing groove 24A. Thus, the guide walls 23 guide the pawls 30 from both sides in the rotational direction so that the pawls 30 slide only radially inward and outward.

Further, each guide wall 23 supports the rotating cam 40 installed in the cam receiving groove 24B from the outside in the radial direction by a support surface 23B which is an inner peripheral surface facing in the radial direction in the cam receiving groove 24B. Thereby, each guide wall 23 is in a state of guiding the rotating cam 40 from the outside in the radial direction so that the rotating cam 40 can rotate at a substantially central (rotation center C) position on the disk main body 21 of the guide 20.

A substantially circular through hole 21A is formed to penetrate axially through a central portion (a position on the rotation center C) of the disk body 21 of the guide 20, and a lock spring 50 described below is installed in the through hole 21A. The through hole 21A is formed with a hanging hole 21Aa extending in a shape elongated outward in the radial direction. The outer end 52 of the lock spring 50 installed in the through hole 21A is fitted into the engaging hole 21Aa in the axial direction, and is integrally installed in the rotational direction.

As shown in fig. 2, the guide 20 is attached such that the outer surface of the disk body 21 abuts against the inner surface of the tilt plate 3F, and is integrally coupled to the tilt plate 3F by welding the abutting portions. Specifically, the guide 20 is set in the following state: three tenon teeth 21B formed so as to protrude from the outer side surface of the disk main body 21 are fitted into three fitting holes 3Fa formed in the inclination adjustment plate 3F, respectively, so that the outer side surface of the disk main body 21 abuts against the inner side surface of the inclination adjustment plate 3F.

The peripheral regions of the respective fitting portions of the guide 20 are joined to the inclination adjustment plate 3F by laser welding. As shown in fig. 4, the tenon teeth 21B are formed by being pushed out in an axially floating island-like manner one by one in the region on the back side of the pawl accommodating grooves 24A (see fig. 5) on the outer side surface of the disk main body 21. As shown in fig. 2, the inclination adjustment plate 3F has a through hole 3Fb formed in a circular hole shape at a position axially opposed to the through hole 21A formed in the center portion (position on the rotation center C) of the guide 20. The operation pin 5A inserted through the through hole 21A of the guide 20 axially penetrates through the through hole 3 Fb.

About detent 30

As shown in fig. 4 to 5, the three pawls 30 have the following structures: a metal plate-like member is cut into a substantially rectangular shape, and each part is processed so as to be pushed out in a half-punched shape in a plate thickness direction (axial direction). Specifically, each pawl 30 is formed in the following shape: the offset surface portion 30B constituting the substantially inner half region in the radial direction is pushed out of the main body surface portion 30A constituting the substantially outer half region in the radial direction by an amount substantially corresponding to the plate thickness in an axial direction as an assembling direction of the ratchet 10.

The three pawls 30 are formed in substantially the same shape, but one of them is formed as a primary pawl P1 having a function different from those of the other two secondary pawls P2. The specific structure will be described in detail later. Hereinafter, a specific structure of each portion common to the pawls 30 will be described.

As shown in fig. 10 to 11, each pawl 30 is installed in the following state: one pawl receiving groove 24A is formed in the inner surface of the disc body 21 of the guide 20. By the installation, the pawls 30 are supported by the restricting surfaces 23A of the guide walls 23 facing the pawl accommodating grooves 24A from both sides in the rotational direction in a planar manner from both sides in the rotational direction. Thereby, the pawls 30 are supported so as to be movable only radially inward and outward along the regulating surfaces 23A.

Specifically, as shown in fig. 9, each pawl 30 is set in the following state: in a state of being set in each pawl accommodating groove 24A (see fig. 5), the body surface portion 30A of each pawl 30 abuts against the inner surface of the disc body 21 of the guide 20. Thereby, each pawl 30 is set in the following state: the internal teeth 12A of the cylindrical portion 12 of the ratchet 10 fitted into the cylindrical portion 22 of the guide 20 are radially opposed to the positions on the outer side in the radial direction of the main body surface portion 30A of each pawl 30. The offset surface portion 30B of each pawl 30 is provided so as to be axially spaced from the inner surface of the disk main body 21 of the guide 20, and is set in a state where the axial arrangement thereof overlaps the intermediate cylindrical portion 13 of the ratchet 10.

As shown in fig. 4, outer teeth 31 having tooth surfaces facing radially outward are formed on the radially outward outer peripheral surface of the main body surface portion 30A of each pawl 30 so as to be continuously aligned over the entire region in the rotational direction. The outer peripheral surface of each pawl 30 on which the external teeth 31 are formed is formed into a convexly curved surface shape that curves along the inner peripheral surface shape of the cylindrical portion 12 of the ratchet 10 on which the internal teeth 12A are formed.

The external teeth 31 of each pawl 30 are formed in a shape in which the tooth surfaces are arranged at equal intervals of 2 degrees in the rotational direction, similarly to the internal teeth 12A of the ratchet 10 that mesh with them. According to the above configuration, as shown in fig. 10, the external teeth 31 of each pawl 30 are pushed into the internal teeth 12A of the ratchet 10 from the inside in the radial direction, and the entire external teeth are meshed with the internal teeth 12A. However, strictly speaking, as shown in fig. 34, the external teeth 31 of each pawl 30 have the following configuration: the tooth surface at the center in the rotational direction thereof meshes with the internal teeth 12A of the ratchet 10 so as to deepest into the internal teeth 12A of the ratchet 10, and the tooth height decreases from the center toward both end sides in the rotational direction so as to become gradually shallower with respect to the entrance of the internal teeth 12A.

Thus, when the pawls 30 are engaged with the internal teeth 12A of the ratchet 10, even if they are pushed out straight outward in the radial direction, all the tooth surfaces of the external teeth 31 do not come into contact with the tooth surfaces of the internal teeth 12A, and can be appropriately engaged with the internal teeth 12A. That is, the tooth surface at the center of the external teeth 31 of each pawl 30 is formed so that the tooth surface is straight in the advancing direction of the meshing movement.

However, the other tooth surfaces arranged from the tooth surface at the center of the external teeth 31 toward both end sides in the rotational direction are configured such that the tooth surface is inclined in the rotational direction with respect to the tooth surface at the center. Therefore, when each pawl 30 is pushed out radially outward, the tooth surface at the center advances straight toward the corresponding tooth surface of the internal teeth 12A of the ratchet 10, but the other teeth enter at an oblique angle toward the corresponding tooth surface of the internal teeth 12A.

However, as described above, the tooth flanks of the external teeth 31 are formed in a shape in which the tooth heights gradually decrease as the tooth flanks on both end sides in the rotational direction approach the tooth flanks from the center tooth flank, and thus even if tooth flanks other than the center tooth flank enter at an oblique angle with respect to the tooth flanks of the internal teeth 12A, a state (meshing state) in which the tooth flanks of the internal teeth 12A enter without abutting against the tooth flanks of the internal teeth 12A can be obtained. The tooth surface shape of the external teeth 31 is the same as that disclosed in japanese patent application laid-open No. 2015-29635 and the like, and therefore, detailed description thereof is omitted.

As shown in fig. 9, a rotary cam 40, which will be described later, provided at the center portion of the guide 20 is provided so as to be opposed to an area on the inner peripheral side of the main body surface portion 30A of each pawl 30 in the radial direction. By the above installation, each pawl 30 is set to the following state: the respective main body surface portions 30A are opposed to the rotating cam 40 in the radial direction, and the respective offset surface portions 30B are opposed to the rotating cam 40 in the axial direction.

As shown in fig. 5, a pressed surface portion 32 is formed on an inner peripheral surface portion of the main body surface portion 30A of each pawl 30, and the pressed surface portion 32 is opposed to the rotating cam 40 in the radial direction and pressed from the inside to the outside in the radial direction in accordance with the rotation of the rotating cam 40. In addition, a pulling hole 33 is formed in an intermediate portion of the offset surface portion 30B of each pawl 30 so as to penetrate in the axial direction, and each pulling pin 42 formed at each corresponding portion of the rotating cam 40 is inserted into the pulling hole 33 in the axial direction and is operated so as to be pulled inward in the radial direction in accordance with the rotation of the rotating cam 40. Further, a multiplying protrusion 34 protruding in the same direction as the pushing direction of the offset surface portion 30B is formed in an intermediate portion of the main body surface portion 30A of each pawl 30.

As shown in fig. 10, the rotating cam 40 is rotated counterclockwise in the figure by the spring biasing force of the lock spring 50 hooked between the rotating cam and the guide 20, whereby the pressed surface portions 32 of the pawls 30 are pressed from the inside to the outside in the radial direction by the corresponding pressing portions 44 formed on the outer peripheral surface portion of the rotating cam 40. Thereby, the external teeth 31 of each pawl 30 are pressed against the internal teeth 12A of the ratchet 10 to mesh with the internal teeth 12A of the ratchet 10, and are held in this state (locked state).

As a result, the pawls 30 are integrally coupled to the ratchet 10 in the rotational direction, and the relative rotation between the ratchet 10 and the guide 20 is locked by the pawls 30. Further, by the engagement accompanying the pressing in the radial direction of each pawl 30, the ratchet 10 and the guide 20 are locked in a state in which the play in the radial direction is suppressed. Such suppression of shaking is also generally referred to as "shaking prevention".

As shown in fig. 11, the rotating cam 40 is rotated clockwise in the figure against the spring biasing force of the lock spring 50 by the operation of the reclining lever 5, and the pulling holes 33 of the ratchet wheels 30 are pulled radially inward by the corresponding pulling pins 42 of the rotating cam 40. Thereby, the pawls 30 are disengaged from the meshed state of their external teeth 31 with the internal teeth 12A of the ratchet 10, and are held in this state (unlocked state). Thereby, the rotation locking state between the ratchet 10 and the guide 20 is released.

As shown in fig. 9, the riding projections 34 of the pawls 30 are pushed out in a half-blanked state in the axial direction (right direction in the figure) to substantially the same positions as the offset surface portions 30B of the pawls 30, and the outer peripheral surface portions 34A of the riding projections 34 are set in a state of facing the inner peripheral surface of the intermediate cylindrical portion 13 of the ratchet 10 in the radial direction. As shown in fig. 10, 17(a) and 18(a), when the rotational position of the ratchet 10 with respect to the guide 20 is in the state of the lock region a1, even if the pawls 30 are pushed outward in the radial direction by the rotating cam 40, the riding projections 34 of the pawls 30 are not pressed against the inner circumferential surface of the intermediate cylindrical portion 13 of the ratchet 10, and the engagement operation of the pawls 30 with the internal teeth 12A of the ratchet 10 is not hindered.

However, as shown in fig. 13, 17(b) and 18(b), when the rotational position of the ratchet 10 with respect to the guide 20 moves to the free region a2, the pawls 30 are pushed outward in the radial direction by the rotating cam 40, and the riding projections 34 of the pawls 30 are pressed against the inner circumferential surface of the intermediate cylindrical portion 13 of the ratchet 10, thereby preventing the pawls 30 from meshing with the internal teeth 12A of the ratchet 10 in the middle. The above-described structure will be described in detail below.

The multiplying projection 34 of each pawl 30 has the following structure: the main pawl P1 and the two other sub pawls P2 are different from each other in radial dimension, i.e., in radial positions, from the center portion (position on the rotation center C) of the guide 20 to the outer peripheral surface portion 34A of each of the riding-up projections 34. Specifically, the multiplied protrusions 34 of the primary pawls P1 are formed at positions that project outward in the radial direction more greatly than the multiplied protrusions 34 of the other two secondary pawls P2.

As shown in fig. 10, 17 a and 18 a, when the riding-up projection 34 of the main pawl P1 is disposed to overlap the first region 13A (lock region a1) of the intermediate cylindrical portion 13 of the ratchet 10 in the rotational direction, it is not pushed out to the position riding up to the first region 13A even if it is pushed out radially outward by the rotating cam 40, and the action of meshing the main pawl P1 with the internal teeth 12A of the ratchet 10 is not hindered.

At this time, even if the riding-on projections 34 of the other two sub pawls P2 are pushed outward in the radial direction by the rotating cam 40, they are not pushed up to the positions on the second region 13B and the third region 13C where they are located, and the operation of meshing the sub pawls P2 with the internal teeth 12A of the ratchet 10 is not hindered. That is, the two sub pawls P2 are formed radially inward of the upper projection 34 of the main pawl P1. Therefore, even if the two sub pawls P2 are disposed so as to overlap the second region 13B (escape region A3) and the third region 13C (escape region A3) that extend radially inward of the first region 13A in the rotational direction, the two sub pawls P2 are not pushed out to positions that are multiplied by the second region 13B and the third region 13C, respectively, when pushed out radially outward by the rotating cam 40.

As shown in fig. 13, 17B and 18B, when the riding-up projection 34 of the main pawl P1 is disposed to overlap the second region 13B (free region a2) of the intermediate cylindrical portion 13 of the ratchet 10 in the rotational direction, it is pushed radially outward by the rotating cam 40 and rides up on the second region 13B, thereby preventing the main pawl P1 from meshing with the internal teeth 12A of the ratchet 10 in the middle.

At this time, even if the riding-on projections 34 of the other two sub pawls P2 are disposed so as to overlap the corresponding third region 13C (escape region A3) and first region 13A (escape region A3) in the rotational direction, when pushed out radially outward by the rotating cam 40, they are not pushed out to the positions where they ride on the third region 13C (escape region A3) and first region 13A (escape region A3), and the movement of each sub pawl P2 radially outward is not prevented. Even with this configuration, the movement of the main pawl P1 is stopped halfway, and the rotation of the rotary cam 40 is stopped halfway, so that each of the sub pawls P2 is no longer pushed outward in the radial direction, and is held together with the main pawl P1 in an unlocked state in which the meshing movement with the internal teeth 12A of the ratchet 10 is stopped halfway.

However, as shown in fig. 4 to 5 and 19 to 20, the riding projections 34 and the offset surface portions 30B of the pawls 30 are formed by being pushed out in a half-blanking shape from the main body surface portion 30A in the same axial direction. When the offset surface portions 30B of the respective pawls 30 are formed, the accuracy control surface Q having accuracy of the forming surface is set not on the outer peripheral surface portion of the offset surface portion 30B of the respective pawls 30 but on the inner peripheral surface portion (pressed surface portion 32) of the main body surface portion 30A. Thus, each pawl 30 has a structure in which the pressed surface portion 32 is formed with high accuracy.

In forming the riding-up projections 34 of the respective pawls 30, the accuracy control surface Q, which provides the accuracy of the forming surface, is set so as to face the outer peripheral surface portion 34A of the respective pawls 30 radially outward of the riding-up projections 34. Thus, the outer peripheral surface portion 34A of each pawl 30 is formed with high accuracy. In this way, the offset surface portion 30B and the riding projection 34 of each of the pawls 30 are formed by being pushed out in a half-cut shape from the main body surface portion 30A so as to be arranged apart from each other in the radial direction, whereby the pawls 30 set the accuracy control surfaces Q on the sides different from each other on the front and back sides, and the accuracy of the molded surface can be obtained.

The regions of the pressed surface portions 32 of the pawls 30 that are offset to both sides in the rotational direction from the portions where the pawls 30 are formed by the protrusions 34 are configured to be pressed from the inside in the radial direction by the corresponding pressing portions 44 of the rotating cam 40 shown in fig. 4. Therefore, the pressed surface portion 32 of each pawl 30 has the following configuration: the accuracy control surface Q is set in the area on both sides where the arrangement in the rotational direction does not overlap with the multiplied protrusion 34 of each pawl 30, and the accuracy control surface Q is not set in the area where the arrangement in the rotational direction overlaps with the multiplied protrusion 34. With this configuration, even when the offset surface portion 30B of each pawl 30 and the riding projection 34 are arranged to overlap each other in the rotational direction, the accuracy control surface Q can be appropriately set, and each molding surface can be molded with high accuracy.

Concerning the rotary cam 40

As shown in fig. 5, the rotary cam 40 has the following structure: a metal plate-like member is cut into a substantially disc-like shape, and each part is processed so as to be pushed out in a half-punched shape in a plate thickness direction (axial direction). The rotary cam 40 is installed in a state of being accommodated in a cam accommodating groove 24B formed on an inner side surface of the disk body 21 of the guide 20. As shown in fig. 9, the rotating cam 40 is formed to have a shape having substantially the same plate thickness as the pawls 30.

The rotary cam 40 is installed so as to be sandwiched in the axial direction between the inner surface of the disk main body 21 of the guide 20 and the offset surface portion 30B pushed out in the axial direction of each pawl 30 in a half-blanked state. Thus, the rotating cam 40 is disposed in a state of being covered from the outside in the radial direction by the pressed surface portion 32 which is the inner peripheral surface portion of the main body surface portion 30A of each pawl 30.

As shown in fig. 5, a through hole 41 is formed in the center portion (position on the rotation center C) of the rotating cam 40, and the operation pin 5A is inserted into the through hole 41 from the inside in the axial direction and is integrally connected in the rotation direction. The operation pin 5A is inserted into the through hole 41 of the rotating cam 40 so as to penetrate from the inner side to the outer side in the axial direction, and the reclining lever 5 shown in fig. 1 is integrally connected to the tip end of the operation pin 5A. By the above-described assembly, the operating pin 5A integrally rotates the rotating cam 40 in accordance with the pulling operation of the reclining lever 5.

The operation pin 5A is integrally connected to an operation pin 5A inserted into the other-side seat reclining device 4 shown in fig. 1 via a link 5B. Thus, the operation of pulling up the reclining lever 5 rotates the operating pins 5A together, and rotates the rotating cams 40 of the reclining devices 4 together.

As shown in fig. 5, the rotary cam 40 is formed in a substantially circular disk shape that is one turn larger than the through hole 21A formed in the center portion (position on the rotation center C) of the guide 20. The rotary cam 40 has two hooking pins 43 formed on its outer surface facing the inside of the through hole 21A of the guide 20 so as to project in the axial direction into the through hole 21A. As shown in fig. 2 and 6, the inner end 51 of the lock spring 50 is hooked on and fixed to the hooking pins 43 so as to be sandwiched between the hooking pins 43. As shown in fig. 10, on the inner surface of the rotating cam 40 facing the offset surface portion 30B of each pawl 30, a pulling pin 42 that enters the pulling hole 33 of each pawl 30 is formed to protrude in the axial direction.

The rotary cam 40 is assembled to the guide 20 in a state of being elastically supported via the lock spring 50. Specifically, the assembly is performed in the following order. First, the rotating cam 40 is installed in the cam receiving groove 24B of the guide 20. Next, the lock spring 50 is set in the through hole 21A of the guide 20, the inner end 51 of the lock spring 50 is hooked between the respective hooking pins 43 of the rotary cam 40, and the outer end 52 is hooked in the hooking hole 21Aa extending from the through hole 21A of the guide 20. As a result, the rotating cam 40 is assembled to the guide 20 in a state of being elastically supported via the lock spring 50.

The rotary cam 40 is biased to rotate counterclockwise in fig. 10 with respect to the guide 20 by the spring biasing force of the lock spring 50 engaged with the guide 20. By the rotation based on the above-described biasing force, the rotating cam 40 presses the pressed surface portion 32 (see fig. 9) of each pawl 30 from the inside in the radial direction by the respective pressing portions 44 formed to protrude from a plurality of places on the outer peripheral surface portion thereof when flat, thereby engaging each pawl 30 with the internal teeth 12A of the ratchet 10.

By pulling up the reclining lever 5 shown in fig. 1, the rotary cam 40 is rotated clockwise as shown in fig. 11 via the operating pin 5A. Thus, the rotating cam 40 pulls the pawls 30 inward in the radial direction by the pulling pins 42 inserted into the pulling holes 33 of the pawls 30, and disengages from the meshing state with the internal teeth 12A of the ratchet 10. Specifically, the rotating cam 40 rotates clockwise as shown in the figure, and the pulling pins 42 are pressed against the inclined surfaces of the pulling holes 33 on the inner peripheral side, which are erected, thereby pulling the pawls 30 inward in the radial direction.

As shown in fig. 10, in the state (locked state) in which the pawls 30 are pushed out from the inside in the radial direction and the pawls 30 are engaged with the internal teeth 12A of the ratchet 10, the end 51 of the rotating cam 40 on the inside of the lock spring 50 engaged with the respective hook pins 43 is disposed in a rotation region between two guide walls M1 on the upper left side and the upper right side in the drawing among the three guide walls 23 formed in the guide 20.

In this state, the rotating cam 40 receives a spring biasing force from the inner end 51 of the lock spring 50, and receives a biasing force in an eccentric direction that is pushed outward in the radial direction in addition to a rotational biasing force in the counterclockwise direction with respect to the guide 20 in the figure. Nevertheless, by the three pawls 30 engaging with the internal teeth 12A of the ratchet 10, the rotating cam 40 is held in a state centered on the center portion (position on the rotation center C) of the guide 20 by being supported from each pawl 30.

As shown in fig. 11, the rotating cam 40 is rotated clockwise in the figure, and each pawl 30 is disengaged from the engagement with the internal teeth 12A of the ratchet 10, and thus, by the biasing force in the eccentric direction received from the inner end 51 of the lock spring 50, the rotating cam 40 is rotated clockwise in the figure while sliding on the support surfaces 23B of the two guide walls M1 while coming into contact with the support surfaces 23B on the inner peripheral sides of the two guide walls M1, as shown in fig. 16. At this time, the remaining guide wall M2 (the lower guide wall M2 shown in the figure) does not contact the outer peripheral surface of the rotating cam 40 unlike the other two guide walls M1, and forms a slight gap T in the radial direction with the outer peripheral surface of the rotating cam 40.

With such a configuration, the rotary cam 40 can be appropriately supported so as not to move in the axial offset direction (the eccentric direction) in the two guide walls M1 with which the rotary cam 40 is brought into contact by the spring biasing force of the lock spring 50. Further, the rotary cam 40 can appropriately avoid the movement of the two guide walls M1 toward the remaining guide wall M2 with the pivot as a fulcrum, which is axially offset (eccentric). Therefore, the rotating cam 40 can be smoothly slid and rotated in the release direction without being eccentric.

About the peripheral ring 60

As shown in fig. 4 to 5, the outer peripheral ring 60 is formed into a substantially cylindrical shape having a hollow disk-shaped seat (flange portion 62) by punching a metal thin plate into a ring shape and drawing the ring so that an outer peripheral edge portion protrudes cylindrically in the axial direction. Specifically, the outer peripheral ring 60 includes: a hollow disk-shaped flange portion 62 having a surface directed straight in the axial direction; and a coupling portion 61 projecting from an outer peripheral edge portion of the flange portion 62 in a substantially cylindrical shape along the axial direction.

Specifically, the outer peripheral edge of the outer peripheral ring 60 is pushed out in two stages in a cylindrical shape with steps in the axial direction. Thus, the outer cylindrical portion of the stepped cylinder is formed into a substantially cylindrical coupling portion 61, and the inner cylindrical portion is formed into a stepped portion 63 having a shorter axial projection length than the coupling portion 61.

The outer peripheral ring 60 is attached so as to straddle between the ratchet 10 and the outer peripheral portion of the guide 20 as described below, and the ratchet 10 and the guide 20 are assembled in a state of being stopped from slipping in the axial direction. First, the three pawls 30, the rotating cam 40, and the locking spring 50 are provided to the guide 20, respectively. Next, the ratchet 10 is assembled to the guide 20, and they are set in the cylinder of the outer peripheral ring 60 (in the coupling portion 61).

As shown in fig. 15, the protruding distal end of the coupling portion 61 is swaged to the outer surface of the cylindrical portion 22 of the guide 20 (swaged portion 61A). As a result, the coupling portion 61 of the outer peripheral ring 60 is integrally coupled to the cylindrical portion 22 of the guide 20, and the flange portion 62 abuts against the ratchet 10 from the outside in the axial direction. Thus, the outer peripheral ring 60 is mounted so as to straddle between the ratchet 10 and the outer peripheral portion of the guide 20, and the ratchet 10 and the guide 20 are assembled in a state of being stopped from moving upward and downward in the axial direction.

As a more detailed description of the above assembly, the outer peripheral ring 60 is set in the following state: the cylindrical portion 22 of the guide 20 abuts against the step portion 63 in the axial direction by being assembled into the cylinder of the outer peripheral ring 60 (into the joint portion 61) in the order from the ratchet 10 to the guide 20. The cylindrical portion 12 of the ratchet 10 is mounted in a state of abutting against the flange portion 62 from the inside in the axial direction. The cylindrical portion 22 of the guide 20 is set by the above setting in a state of being fitted into the cylindrical coupling portion 61 of the outer peripheral ring 60 in the axial direction.

After the installation, a distal end portion (a caulking portion 61A) of the coupling portion 61 of the outer peripheral ring 60, which extends outward in the axial direction from the cylindrical portion 22 of the guide 20, is bent inward in the radial direction, and thereby is caulked to the outer side surface of the cylindrical portion 22 so as to sandwich the cylindrical portion 22 of the guide 20 between the portion and the stepped portion 63 in the axial direction. Thereby, the outer peripheral ring 60 is integrally coupled to the guide 20, and the flange portion 62 abuts against the ratchet 10 from the outside in the axial direction, thereby holding the ratchet 10 in a state where it does not fall off in the axial direction.

Specifically, the flange portion 62 of the outer peripheral ring 60 is attached such that a radially inward projecting tip portion thereof is attached to an inclined surface 13G formed on an axially outer side surface of a portion connecting the intermediate cylindrical portion 13 and the cylindrical portion 12 of the ratchet 10. The inclined surface 13G is formed in a shape such that the surface is inclined outward in the radial direction. Therefore, by attaching the tip end portion of the flange portion 62 of the outer peripheral ring 60 to the inclined surface 13G, the ratchet 10 is prevented from shaking outward in the axial direction and outward in the radial direction.

As shown in fig. 5 and 7, inclined abutting portions 62A caulked so as to project obliquely inward in the axial direction are formed at three positions in the rotational direction of the flange portion 62 of the outer peripheral ring 60. When arranged to overlap each of the inclined projecting surfaces 13H in the rotational direction, the inclined contact portions 62A ride up the corresponding inclined projecting surfaces 13H, and the inclined projecting surfaces 13H are formed at three positions in the rotational direction on the inclined surface 13G of the ratchet 10 and project so that the surfaces thereof are inclined outward in the axial direction and outward in the radial direction. By the above multiplication, each of the inclined contact portions 62A is in a state in which the axial outward and radial outward play of the ratchet 10 is more appropriately suppressed.

Each of the inclined contact portions 62A of the flange portion 62 is formed by bending the flange portion 62 so as to be partially inclined inward in the axial direction from a joint with the stepped portion 63. The respective projecting inclined surfaces 13H formed on the inclined surface 13G of the ratchet 10 are formed to project substantially in parallel with the inclined surface 13G by a die shape pressed at the time of half blanking of the ratchet 10.

The respective projecting inclined surfaces 13H are arranged at three positions in the rotation direction on the inclined surface 13G uniformly. Each of the projecting inclined surfaces 13H has a length in the rotational direction of about 20 degrees. Guide slopes 13H1 are formed on both sides of each protrusion slope 13H in the rotational direction, and the guide slopes 13H1 are thickened so as to connect the steps between the protrusion slopes 13H and the slopes 13G in a sloping manner. In addition, the inclined contact portions 62A of the outer peripheral ring 60 formed on the flange portion 62 are equally disposed at three positions in the rotational direction on the flange portion 62. Each of the inclined contact portions 62A also has a length in the rotational direction of about 20 degrees.

As shown in fig. 21, when the backrest angle of the seat back 2 is in the angle region between the primary lock position Pb in which the backrest angle is in the upright posture and the trunk angle Pd (approximately 20 degrees), the outer peripheral ring 60 is brought into abutment with the respective inclined abutment portions 62A by the respective projecting inclined surfaces 13H formed on the inclined surface 13G of the ratchet 10 being multiplied by the respective inclined abutment portions 62A of the flange portion 62 as shown in fig. 22 to 23 (abutment region B1).

Thus, the outer peripheral ring 60 is held in a state in which the respective inclined contact portions 62A appropriately suppress the axial and radial play of the ratchet 10. At this time, as shown in fig. 24, the normal surface of the flange portion 62 of the outer peripheral ring 60 is in a non-contact state in which it is not in contact with and separated from the normal surface of the inclined surface 13G of the ratchet 10. As shown in fig. 21, the above-described abutment region B1 is set in an angular region of approximately 40 degrees between an angular position where the backrest angle of the seat back 2 is inclined approximately 10 degrees to the front side from the primary lock position Pb (upright position) and an angular position where the backrest angle is inclined approximately 10 degrees to the rear side from the trunk angle Pd.

In the contact region B1, as shown in fig. 22, since the effect of suppressing the rattling of the ratchet 10 by the outer peripheral ring 60 is relatively strong, the rotational movement of the ratchet 10 relative to the guide 20 is easily suppressed by the effect of the sliding frictional resistance caused by the contact of the outer peripheral ring and the ratchet. However, as described above, when the seat back 2 is in the rising angle region, the urging force of the return spring 6 (see fig. 1) that urges the seat back 2 in the forward rotation direction acts relatively strongly. Therefore, even if the rattling prevention is strongly exerted as described above, the seat back 2 can be smoothly rotated and moved.

Further, as shown in fig. 25, when the backrest angle of the seat back 2 shifts from the abutment region B1 shown in fig. 21 to an angle region that is offset to the rear side, the outer peripheral ring 60 is offset in the rotational direction from the corresponding inclined abutment portion 62A of the flange portion 62 by each of the projecting inclined surfaces 13H formed on the inclined surface 13G of the ratchet 10, as shown in fig. 26 to 28. Thus, the outer peripheral ring 60 is in a non-contact state (non-contact region B2) in which the inclined surface 13G of the ratchet 10 faces each of the inclined contact portions 62A of the flange portion 62 of the outer peripheral ring 60 with a slight gap therebetween.

In the non-contact state, the effect of suppressing the rattling of the ratchet 10 by the outer peripheral ring 60 is reduced, but the ratchet 10 is rotated smoothly relative to the guide 20 accordingly. Therefore, when the seat back 2 is in the rearward-inclined angle region as described above, even if the urging force of the return spring 6 (see fig. 1) that urges the seat back 2 in the forward rotation direction is relatively weak, the seat back 2 can be smoothly lifted up toward the front side.

Further, as shown in fig. 29, when the backrest angle of the seat back 2 shifts from the abutment region B1 shown in fig. 21 to an angle region deviated to the front side, the outer peripheral ring 60 is also deviated in the rotational direction from the respective inclined abutment portions 62A of the flange portion 62 by the respective projecting inclined surfaces 13H formed on the inclined surfaces 13G of the ratchet 10 as shown in fig. 30 to 32. Thus, the outer peripheral ring 60 is in a non-contact state (non-contact region B2) in which the inclined surface 13G of the ratchet 10 faces each of the inclined contact portions 62A of the flange portion 62 of the outer peripheral ring 60 with a slight gap therebetween.

In the non-contact state, the effect of suppressing the rattling of the ratchet 10 by the outer peripheral ring 60 is reduced, but the ratchet 10 is rotated smoothly relative to the guide 20 accordingly. Therefore, when the seat back 2 is in the forward-inclined angle region as described above, even if the force for lifting the seat back 2 rearward becomes large, the seat back 2 can be lifted relatively smoothly rearward.

Structure for preventing rattling of the main ratchet P1

As shown in fig. 34, the main pawl P1 includes the following rattling prevention structure: when the cam 40 is pressed and engaged with the internal teeth 12A of the ratchet 10, the guide walls 23 on both sides are slightly inclined so as to be caught therebetween, and the rattling in the rotational direction is prevented. The rattling prevention structure of the primary pawl P1 will be described in detail below.

The main pawl P1 has a first projection 35A formed on a side portion of the main body surface portion 30A on the counterclockwise direction side (right side in the figure) in the figure and projecting toward the opposing guide wall 23. A second protrusion 35B protruding toward the opposing guide wall 23 is also formed on the side portion of the main body surface portion 30A of the main pawl P1 on the clockwise direction side (left side in the figure).

The first projection 35A is formed on the main body surface portion 30A of the main pawl P1 on the counterclockwise side in the figure, at a position inward of the center in the radial direction. The first projection 35A is formed so as to project in the counterclockwise direction in the drawing in a convexly curved surface shape having the same cross section over the entire region in the plate thickness direction of the main pawl P1. The second projection 35B is formed at a radially outer end position of the side portion on the clockwise direction side in the drawing of the main body surface portion 30A of the main pawl P1. The second projection 35B is formed to project in the clockwise direction as viewed in the drawing in a trapezoidal shape having the same cross section over the entire region of the primary pawl P1 in the plate thickness direction.

As shown in fig. 35, the primary pawl P1 has the following structure: in order to ensure the sliding performance of the primary pawls P1 radially inward and outward, a gap S in the rotational direction is provided between the guide walls 23 on both sides thereof. However, by setting the gap S, when the main pawl P1 is pushed outward in the radial direction by the rotating cam 40 as described with reference to fig. 10, there is a possibility that play may occur between the guide walls 23, the play being inclined in the rotational direction.

Specifically, as shown in fig. 35, the primary pawl P1 has the following structure: the rotating cam 40 is pressed from the inside to the outside in the radial direction at a pressing point R eccentric in the counterclockwise direction in the figure from the center position in the rotation direction of the main pawl P1. Therefore, the primary pawl P1 has the following structure: by the pressing force, the main pawl P1 rotates clockwise in the drawing between the guide walls 23 with the pressing point R as a fulcrum, and is pushed out to a position where it engages with the internal teeth 12A of the ratchet 10. Alternatively, the primary pawl P1 has the following structure: after the tooth surface at the center thereof meshes with the internal teeth 12A of the ratchet 10, the ratchet can rotate clockwise in the illustrated example with the meshing point K of the tooth surface at the center which meshes with the internal teeth 12A deepest as a fulcrum.

When the rotation of the main pawl P1 occurs as described above, the main pawl P1 is inclined so as to be caught between the two guide walls 23, and thereby the main pawl P1 can be brought into a state in which rattling in the rotational direction is reduced. However, when the inclination is large, the main pawl P1 may move around the central tooth surface of the outer teeth 31 that most deeply meshes with the inner teeth 12A of the ratchet 10, and the tooth surface on the one end side may become shallower in depth of meshing with the inner teeth 12A. Therefore, in order not to cause such a problem, the main pawl P1 is configured as follows: when the guide walls 23 are inclined, the first projection 35A and the second projection 35B are brought into contact with the guide walls 23 on the respective sides, whereby the rattling in the rotational direction can be prevented without being largely inclined.

Specifically, as shown in fig. 35, when the main pawl P1 is pressed from the inside to the outside in the radial direction by the rotating cam 40, the main pawl P1 rotates clockwise as shown in the figure. However, due to this rotation, the first projection 35A abuts against the opposing guide wall 23, and thus the rotation of the main pawl P1 in this direction can be prevented as soon as possible. When the main pawl P1 is engaged with the internal teeth 12A of the ratchet 10 from this state, a force applied from the pressing point R applies a clockwise rotational force to the main pawl P1, as shown in the figure, about the engagement point K between the tooth surface at the center of the external teeth 31 and the internal teeth 12A.

Accordingly, the main pawl P1 applies a pressing force along with the rotational force to the guide wall 23 on the side abutting on the first projection 35A. In reaction to this, the main pawl P1 exerts a rotational force that presses and rotates the internal teeth 12A that are in contact with the central tooth surface (meshing point K) clockwise as viewed in the figure, with the contact point of the first projection 35A and the guide wall 23 as a fulcrum. Thus, the main pawl P1 slightly rotates in the clockwise direction as shown in fig. 36 by itself with the contact point of the first projection 35A and the guide wall 23 as a fulcrum, and presses and rotates the ratchet 10 in this direction to cause the second projection 35B to contact the opposite guide wall 23.

The rotation of the main pawl P1 is prevented as soon as possible by the abutment of the second projection 35B with the guide wall 23. By the abutment, the main pawl P1 is in the following state: the inner teeth 12A of the ratchet 10 are engaged with each other in a state where the play is reduced in the rotational direction between the guide walls 23.

As described above, by the structure in which the first projection 35A and the second projection 35B of the main pawl P1 abut against the guide walls 23 on each side, rattling of the main pawl P1 between both the guide walls 23 in the rotational direction is appropriately suppressed. This allows the tooth surfaces on both ends of the external teeth 31 of the main pawl P1 to be held in a balanced and well meshed state with respect to the internal teeth 12A of the ratchet 10 without making the meshing on one side shallow.

The contact of the main pawl P1 with the guide wall 23 on each side and the engagement of the tooth surface (engagement point K) at the center of the external teeth 31 with the internal teeth 12A of the ratchet 10 may occur first. That is, this is because, when any phenomenon occurs first, the other one of the contact and the engagement occurs due to the reaction caused by the phenomenon. As described above, by engaging the main pawl P1 with the ratchet 10 in a state in which the backlash in the rotational direction with respect to the guide 20 is reduced, the backlash in the rotational direction between the ratchet 10 and the guide 20 can be reduced appropriately even if there is backlash in the rotational direction between the other sub pawls P2 and the guide 20 shown in fig. 10.

Summary of the invention

As described above, the seat reclining device 4 according to the present embodiment has the following configuration. In addition, the reference numerals indicated below with parentheses are those corresponding to the respective configurations shown in the above embodiments.

Specifically, a vehicle seat reclining device (4) is provided with: a ratchet (10) and a guide (20) that are assembled in an axial direction so as to be rotatable relative to each other; a pawl (30) supported by a pair of guide walls (23) provided on the guide (20) from both sides in the rotational direction, and engaged with the ratchet (10) by being pushed radially outward to restrict relative rotation of the ratchet (10) and the guide (20); and a cam (40) that pushes the pawl (30) from the inside to the outside in the radial direction.

The pawl (30) has: an eccentric structure that is pressed and tilted to one side in the rotational direction between the pair of guide walls (23) by a pressing force received from the cam (40); and a first protrusion (35A) that protrudes from one side surface of the pawl (30) in the rotational direction and limits the tilt of the pawl (30) by coming into contact with the opposing guide wall (23).

According to the above configuration, a gap (S) in the rotation direction can be provided between the pawl (30) and each guide wall (23), and the inclination of the pawl (30) in the gap (S) can be restricted by the abutment of the first projection (35A) and the guide wall (23). This can ensure the sliding property of the pawl (30) and suppress rattling at the same time.

The pawl (30) has a second protrusion (35B), wherein the second protrusion (35B) protrudes from the other side surface of the pawl (30) in the rotational direction, and the pawl (30) is held in a posture in which it contacts both of the pair of guide walls (23) by contact with the opposing guide walls (23). According to the above configuration, the pawl (30) can be held in a state of abutting against the two guide walls (23) and filling up the gap (S) in the rotational direction, and thus the rattling of the pawl (30) can be more appropriately suppressed.

The second projection (35B) is located radially outward of the first projection (35A).

According to the above configuration, when the pawl (30) is inclined in a direction in which the gap (S) between the guide wall (23) and the other side surface close to the outer peripheral side of the meshing portion with the ratchet (10) is filled with, using the contact point of the first protrusion (35A) and the guide wall (23) as a base point, the second protrusion (35B) can be brought into contact with the guide wall (23) at a relatively early stage to restrict the inclination of the pawl (30).

In addition, a plurality of pawls (30) are provided, and a first protrusion (35A) is formed only on a specific pawl (P1). According to the structure, the shaking of the pawl (30) can be reasonably restrained.

(second embodiment)

Next, the structure of the seat reclining device 4 according to the second embodiment of the present invention will be described with reference to fig. 37. In the present embodiment, the rattle prevention structure of the main pawl P1 is formed by the first protrusion 35C and the second protrusion 35B formed at the side portion of the main pawl P1. The first projection 35C is formed on the outer side of the radial center of the counterclockwise side (right side in the drawing) of the main body surface portion 30A of the main pawl P1. The first projection 35C is formed so as to project in the counterclockwise direction in the drawing in a convexly curved surface shape having the same cross section over the entire region in the plate thickness direction of the main pawl P1. The second projection 35B is formed at the same position as that shown in the first embodiment.

As described above, the first projection 35C is formed on the main body surface portion 30A of the primary pawl P1 on the outer peripheral side, whereby the following effects can be obtained. That is, even if the main pawl P1 receives a force from the ratchet 10 to be pushed and rotated in the counterclockwise direction in the figure after the first projection 35C abuts against the guide wall 23 facing thereto, the main pawl P1 is easily pushed and rotated in the clockwise direction in the figure with the abutting point of the first projection 35C against the guide wall 23 as a fulcrum by the pushing force received from the rotating cam 40.

Therefore, the first projection 35C and the second projection 35B can be appropriately pressed against the guide wall 23 on each side. Since the configurations other than the above are the same as those shown in the first embodiment, the same reference numerals are given thereto and the description thereof is omitted.

(third embodiment)

Next, the structure of a seat reclining device 4 according to a third embodiment of the present invention will be described with reference to fig. 38. In the present embodiment, the rattle prevention structure of the main pawl P1 is formed by the first protrusion 35D and the second protrusion 35E formed at the side portion of the main pawl P1. These first projection 35D and second projection 35E are respectively formed in the following shapes: the protruding slope extends over the entire area of the edge portion outward from the radially inner edge portion of the primary pawl P1.

Specifically, the apex of the first projection 35D is set at a position (the same position as in the second embodiment) outward of the center in the radial direction in the main body surface portion 30A of the primary pawl P1. The first projection 35D is formed to project uniformly in cross section over the entire region of the main pawl P1 in the plate thickness direction. The first projection 35D is formed in the following shape: from the apex of the above-described protrusion, protruding slopes are respectively extended between the radially inner edge and the radially outer edge of the side portion of the primary pawl P1.

Specifically, the first protrusion 35D has the following structure: the inclined surface extending radially outward from the apex of the protrusion is formed as an edge extending straight to the outside of the side region of the main body surface portion 30A except for the outer teeth 31. The first protrusion 35D has the following structure: the inclined surface extending radially inward from the apex of the protrusion is formed as an edge portion extending straight to the inside of the side region of the offset surface portion 30B beyond the side region of the main body surface portion 30A.

The projecting apex of the second projection 35E is set at a position outside the center in the radial direction (position near the outer edge) of the main body surface portion 30A of the main pawl P1. The second projection 35E is formed so that the entire area of the main pawl P1 in the plate thickness direction protrudes in the same cross section. The second projection 35E is formed in the following shape: from the apex of the above-described protrusion, protruding slopes are respectively extended between the radially inner edge and the radially outer edge of the side portion of the primary pawl P1.

Specifically, the second protrusion 35E has the following structure: the inclined surface extending radially outward from the apex of the protrusion is formed as an edge extending straight to the outside of the side region of the main body surface portion 30A except for the outer teeth 31. The second protrusion 35E has the following structure: the inclined surface extending radially inward from the apex of the protrusion is formed as an edge portion extending straight to the inside of the side region of the offset surface portion 30B beyond the side region of the main body surface portion 30A.

The first projection 35D and the second projection 35E are formed before the offset surface portion 30B of the main pawl P1 is half-blanked and pushed out from the main body surface portion 30A. The first projection 35D and the second projection 35E are configured such that the above-described processing procedure enables the formation thereof to be performed easily and with high accuracy, as compared with the case where they are formed after the half blanking process. Further, the first projection 35D and the second projection 35E are formed in such a shape that the inclined surfaces extend long inward and outward in the radial direction, respectively, and thus, compared with a case where they are formed partially at the side portion of the main pawl P1, they can be formed easily and with high accuracy.

The first projection 35D and the second projection 35E are configured to have higher structural strength than those of the case where the first projection and the second projection are partially formed on the side portion of the primary pawl P1. The first projection 35D and the second projection 35E may be formed in such a shape that the projecting slopes extend at least over the entire radial area of the main body surface portion 30A, or do not extend to the offset surface portion 30B. Since the configurations other than the above are the same as those shown in the first embodiment, the same reference numerals are given thereto and the description thereof is omitted.

Summary of the invention

Namely, the pawl (30) has: an eccentric structure that is pressed and tilted to one side in the rotational direction between the pair of guide walls (23) by a pressing force received from the cam (40); and a first protrusion (35D) which protrudes from one side surface in the rotation direction and limits the inclination of the pawl (30) by contacting with the opposite guide wall (23).

According to the above configuration, a gap (S) in the rotational direction can be provided between the pawl (30) and each guide wall (23), and the inclination of the pawl (30) in the gap (S) can be restricted by the contact of the first protrusion (35D) with the guide wall (23). This can ensure the sliding property of the pawl (30) and suppress rattling at the same time.

The pawl (30) has a second protrusion (35E), wherein the second protrusion (35E) protrudes from the other side surface of the pawl (30) in the rotation direction, and the pawl (30) is held in a posture in which it contacts both of the pair of guide walls (23) by contact with the opposing guide walls (23). According to the above configuration, the pawl (30) can be held in a state of abutting against the two guide walls (23) and filling up the gap (S) in the rotational direction, and thus the rattling of the pawl (30) can be more appropriately suppressed.

The second projection (35E) is located radially outward of the first projection (35D). According to the above configuration, when the pawl (30) is inclined in a direction in which the gap (S) between the guide wall (23) and the other side surface close to the outer peripheral side of the meshing portion with the ratchet (10) is filled with, using the contact point of the first protrusion (35D) and the guide wall (23) as a base point, the second protrusion (35E) can be brought into contact with the guide wall (23) at a relatively early stage to restrict the inclination of the pawl (30).

Further, the pawl (30) has: a main body surface portion (30A) which receives a pressing force from the inside in the radial direction by a cam (40); and an offset surface part (30B) having a shape that is pushed out from the main body surface part (30A) in a half-blanking shape in the axial direction, and arranged in parallel with the cam (40) in the axial direction. The second protrusion (35E) has a shape in which the slope of the second protrusion (35E) extends over at least the entire region of the main body surface (30A) on the other side surface of the pawl (30) in the direction of rotation. According to the above configuration, the structural strength of the second protrusion (35E) can be improved as compared with a configuration in which the second protrusion (35E) is partially formed on the other side surface in the rotational direction of the pawl (30). In addition, the second protrusion (35E) can be simply formed.

In addition, a plurality of pawls (30) are provided, and a first protrusion (35D) is formed only on a specific pawl (P1). According to the structure, the shaking of the pawl (30) can be reasonably restrained.

The first projection (35D) has a shape in which the side surface of the protruding inclined surface on one side in the rotational direction of the pawl (30) extends over at least the entire region of the main body surface (30A). According to the above configuration, the structural strength of the first protrusion (35D) can be improved as compared with a configuration in which the first protrusion (35D) is partially formed on one side surface in the rotational direction of the pawl (30). In addition, the first protrusion (35D) can be simply formed.

(fourth embodiment)

Next, a structure of a seat reclining device 4 according to a fourth embodiment of the present invention will be described with reference to fig. 39. In the present embodiment, the rattling prevention structure of the main pawl P1 is formed by the first protrusion 23C and the second protrusion 23D, and the first protrusion 23C and the second protrusion 23D are formed on the regulation surfaces 23A of the respective guide walls 23 that support the main pawl P1 from both sides in the rotation direction.

Specifically, the first projection 23C is formed to project in a mountain shape from a side in contact with a position outside the center in the radial direction of the main body surface portion 30A (a position corresponding to the contact point of the second embodiment) when the main pawl P1 is engaged with the ratchet 10. The first projection 23C is formed so as to project in the clockwise direction in the drawing in a convex curved shape having the same cross section over the entire area of the guide wall 23 in the plate thickness direction.

The second projection 23D is formed to project in a mountain shape from a side in contact with a position outside the center in the radial direction (a position near the outer edge portion: a position corresponding to the contact point of the second embodiment) of the main body surface portion 30A when the main pawl P1 is engaged with the ratchet 10. The second projection 23D is formed so as to project in the counterclockwise direction in the drawing in a convex curved surface shape having the same cross section over the entire area of the guide wall 23 in the plate thickness direction.

The first projection 23C and the second projection 23D are disposed radially inward of the outer teeth 31 of the main pawl P1 even when the main pawl P1 is pulled radially inward to the maximum extent from being disengaged from the ratchet 10. Thus, the first projection 23C and the second projection 23D do not abut against the main pawl P1 in the radial direction when the main pawl P1 is pushed outward in the radial direction to engage with the ratchet 10. Since the configurations other than the above are the same as those shown in the first embodiment, the same reference numerals are given thereto and the description thereof is omitted.

Summary of the invention

Specifically, a vehicle seat reclining device (4) is provided with: an eccentric structure that presses the pawl (30) to one side in the rotational direction between the pair of guide walls (23) by a pressing force received from the cam (40) and tilts the pawl (30); and a first protrusion (23C) which protrudes from a guide wall (23) facing a side surface on one side in the rotation direction of the pawl (30) and limits the inclination of the pawl (30) by contacting with the pawl (30).

According to the above configuration, a gap (S) in the rotational direction can be provided between the pawl (30) and each guide wall (23), and the inclination of the pawl (30) in the gap (S) can be restricted by the contact of the first protrusion (23C) with the pawl (30). This can ensure the sliding property of the pawl (30) and suppress rattling at the same time.

The vehicle seat reclining device (4) further comprises a second protrusion (23D) which protrudes from the guide wall (23) facing the other side surface of the pawl (30) in the direction of rotation, and which is configured to maintain the pawl (30) in a posture in which it contacts both of the pair of guide walls (23) by limiting the tilt of the pawl (30) through contact with the pawl (30).

According to the above configuration, the pawl (30) can be held in a state of abutting against the two guide walls (23) and filling up the gap (S) in the rotational direction, and thus the rattling of the pawl (30) can be more appropriately suppressed.

(fifth embodiment)

Next, a structure of a seat reclining device 5 according to a fourth embodiment of the present invention will be described with reference to fig. 40. In the present embodiment, the rattling prevention structure of the main pawl P1 is formed by the first protrusion 23E and the second protrusion 23F, which are formed on the regulation surface 23A that supports each guide wall 23 of the main pawl P1 from both sides in the rotational direction. These first projection 23E and second projection 23F are respectively formed in the following shapes: the protruding slope extends over the entire area of the edge portion from the inner edge portion to the outer edge portion in the radial direction of each regulating surface 23A.

Specifically, the apex of the first projection 23E is formed at a position laterally abutting a position outside the center in the radial direction of the main body surface portion 30A (a position corresponding to the abutment point of the fourth embodiment) when the main pawl P1 meshes with the ratchet 10. The first protrusion 23E is formed so that the entire cross section of the guide wall 23 in the plate thickness direction protrudes uniformly. The first projection 23E is formed in the following shape: from the apex of the protrusion, the inclined surfaces of the protrusion extend between the inner edge (arc end) and the outer edge (arc end) in the radial direction of the limiting surface 23A of the guide wall 23.

Specifically, the first protrusion 23E has the following structure: the inclined surface extending radially outward from the apex of the protrusion is formed as an edge (arc tip) extending straight to the radially outer side of the regulating surface 23A of the guide wall 23. The first protrusion 23E has the following structure: the inclined surface extending radially inward from the apex of the protrusion is formed to extend straight to the radially inward edge (arc tip) of the limiting surface 23A of the guide wall 23.

The projecting apex of the second projection 23F is formed at a position laterally abutting a position outside the center in the radial direction (a position near the outer edge portion: a position corresponding to the abutting point in the fourth embodiment) in the main body surface portion 30A when the main pawl P1 meshes with the ratchet 10. The second projection 23F is formed so as to protrude in the same cross section over the entire area of the guide wall 23 in the plate thickness direction. The second projection 23F is formed in the following shape: from the apex of the protrusion, the inclined surfaces of the protrusion extend between the inner edge (arc end) and the outer edge (arc end) in the radial direction of the limiting surface 23A of the guide wall 23.

Specifically, the second protrusion 23F has the following structure: the inclined surface extending radially outward from the apex of the protrusion is formed as an edge (arc tip) extending straight to the radially outer side of the regulating surface 23A of the guide wall 23. The second protrusion 23F has the following structure: the inclined surface extending radially inward from the apex of the protrusion is formed to extend straight to the radially inward edge (arc tip) of the regulating surface 23A of the guide wall 23.

The first projection 23E and the second projection 23F are formed in such a shape that the inclined surfaces extend long inward and outward in the radial direction, respectively, and thus, compared to a case where they are formed locally on the regulating surface 23A of each guide wall 23, they can be formed easily and with high accuracy. The first projection 23E and the second projection 23F are configured to have higher structural strength than those of the first projection and the second projection that are partially formed on the regulating surface 23A of each guide wall 23.

The first projection 23E and the second projection 23F are formed in the following shapes: even when the main pawl P1 is maximally pulled radially inward from being disengaged from the ratchet 10, the apexes of the first projections 23E and the second projections 23F are located radially inward of the outer teeth 31 of the main pawl P1. Accordingly, when the main pawl P1 is pushed radially outward to engage with the ratchet 10, the first projection 23E and the second projection 23F are inclined so as to rise toward the projecting apexes of the first projection 23E and the second projection 23F, and the main pawl P1 is not prevented from moving radially outward. Since the configurations other than the above are the same as those shown in the first embodiment, the same reference numerals are given thereto and the description thereof is omitted.

Summary of the invention

Specifically, a vehicle seat reclining device (4) is provided with: an eccentric structure that presses the pawl (30) to one side in the rotational direction between the pair of guide walls (23) by a pressing force received from the cam (40) and tilts the pawl (30); and a first protrusion (23E) which protrudes from a guide wall (23) facing a side surface on one side in the rotation direction of the pawl (30) and limits the inclination of the pawl (30) by contacting with the pawl (30).

According to the above configuration, a gap (S) in the rotation direction can be provided between the pawl (30) and each guide wall (23), and the inclination of the pawl (30) in the gap (S) can be restricted by the abutment of the first projection (23E) and the pawl (30). This can ensure the sliding property of the pawl (30) and suppress rattling at the same time.

The vehicle seat reclining device (4) further comprises a second protrusion (23F) which protrudes from the guide wall (23) facing the other side surface of the pawl (30) in the rotational direction, and which is configured to limit the tilt of the pawl (30) by contact with the pawl (30), thereby holding the pawl (30) in a position in which it is in contact with both of the pair of guide walls (23). According to the above configuration, the pawl (30) can be held in a state of abutting against the two guide walls (23) and filling up the gap (S) in the rotational direction, and thus the rattling of the pawl (30) can be more appropriately suppressed.

The second projection (23F) is formed in such a shape that the slope of the second projection (23F) extends over the entire area of the side surface of the guide wall (23) that faces the pawl (30). According to the above configuration, the structural strength of the second protrusion (23F) can be improved as compared with a configuration in which the second protrusion (23F) is partially formed on the guide wall (23). In addition, the second protrusion (23F) can be simply formed.

The first projection (23E) is formed in such a shape that the slope of the first projection (23E) extends over the entire area of the side surface of the guide wall (23) that faces the pawl (30). According to the above configuration, the structural strength of the first protrusion (23E) can be improved as compared with a configuration in which the first protrusion (23E) is partially formed on the guide wall (23). In addition, the first protrusion (23E) can be simply formed.

(related to other embodiments)

While the embodiments of the present invention have been described above using five embodiments, the present invention can be implemented in various forms other than the above-described embodiments.

1. The vehicle seat reclining device according to the present invention can be widely applied to seats for various vehicles such as vehicles other than automobiles such as railways, aircrafts, and ships, in addition to seats other than right seats of automobiles. In addition, the vehicle seat reclining device may be configured to couple the seat back to the seat cushion in a state in which the backrest angle is adjustable, or to couple the seat back to a base such as a bracket fixed to the vehicle body side in a state in which the backrest angle is adjustable.

2. The vehicle seat reclining device may have the following structure: the ratchet is coupled to a base fixed to the vehicle body side, such as a seat cushion, and the guide is coupled to the seat back.

3. Two or more pawls that lock relative rotation between the ratchet and the guide may be provided in the rotational direction. The arrangement of the pawls in the rotational direction is not limited to the uniform arrangement, and may be arranged offset to one side.

4. The cam for pushing each pawl from the inside to the outside in the radial direction is not limited to the rotary type, and may be a slide type in which each pawl is pushed to the outside in the radial direction by sliding in the radial direction as disclosed in japanese patent application laid-open publication No. 2014-217662 and the like. The operation of pulling back the pawls inward in the radial direction may be performed by using a member separate from the cam, such as a release plate as disclosed in japanese patent application laid-open No. 2015-227071 and the like.

5. The abutting portion of the outer peripheral ring may abut straight from the outside in the axial direction, in addition to abutting obliquely with respect to the ratchet. The outer peripheral ring may have the following structure: the engaging portion engages with the ratchet, and the abutting portion abuts against the guide from the outer side in the axial direction. The joint portion of the outer peripheral ring may be joined by welding, in addition to being riveted to one of the ratchet and the guide. The cylindrical portion may be set to the ratchet instead of the guide, and may cover the guide in a surrounding manner from the outer peripheral side.

6. The eccentric structure of the pawl, that is, the eccentric structure in which the force that is pushed and inclined to one side in the rotational direction is applied between the pair of guide walls by the pushing force applied from the cam, may be configured such that the pawl is pushed from the inside to the outside in the radial direction at a position eccentric to the rotational direction by the cam, or may be configured such that the pawl is pushed and inclined to the rotational direction by the cam.

7. The second projection need only be located at least radially outward of the first projection, and need not be located at the radially outward end of the pawl. The projection shape and the projection amount of the first projection and the second projection are appropriately determined according to their arrangement in the radial direction in the pawl.

That is, the projection height required for the first projection becomes shorter as the first projection approaches the radially inner side of the pawl. Further, the projection height required for the second projection is shorter as the second projection approaches the outer side of the pawl in the radial direction. In addition, the pawl may have only the first projection and no second projection. One of the first projection and the second projection may be formed on the pawl, and the other may be formed on the guide.

The present application is based on the japanese patent application filed on 25/4/2019 (japanese patent application 2019-084148) and on 3/2020 (japanese patent application 2020-035602), the contents of which are hereby incorporated by reference.

Industrial applicability

According to the vehicle seat reclining device of the present invention, both the securing of the slidability of the pawl and the suppression of the rattling can be achieved. The present invention having such an effect can be used as a seat reclining device used for a seat of an automobile or the like, for example.

Description of the reference numerals

1 seat

2 seat back

2F side frame

2Fa fitting hole

2Fb through hole

2Fc clamping plate

2 seat cushion

3F inclination angle adjusting plate

3Fa fitting hole

3Fb through hole

3Fc front stop

3Fd rear stopper

4 seat inclination angle adjusting device (vehicle seat inclination angle adjusting device)

5 Dip angle adjusting rod

5A operating pin

5B connecting rod

6 reset spring

10 ratchet wheel

11 circular plate body

11A through hole

11B dilate face

12 cylindrical part

12A internal tooth

13 intermediate cylindrical part

13A first region

13B second region

13C third region

13D first convex part

13E second projection

13E1 relief recess

Y gap

13G inclined plane

13H protruding inclined plane

13H1 guide ramp

A1 locking region

A2 free region

A3 avoidance zone

A4 binding region

14 tenon tooth

B1 abutment area

B2 non-abutting region

20 guide piece

21 circular plate body

21A through hole

21Aa hanging hole

21B tenon tooth

22 cylindrical part

23 guide wall

23A limiting surface

23B bearing surface

23C first projection

23D second projection

23E first projection

23F second projection

M1 guide wall

M2 guide wall

T gap

24A pawl accommodating groove

24B cam receiving groove

30 ratchet pawl

30A body face

30B offset face

31 external tooth

32 is pressed on the face

33 pulling hole

34 by the projection

34A outer peripheral surface portion

35A first projection

35B second projection

35C first projection

35D first projection

35E second projection

P1 Main pawl (Special pawl)

P2 secondary pawl

Q surface of quality control

40 rotating cam (cam)

41 through hole

42 pulling pin

43 hook pin

44 pressing part

50 locking spring

51 inner end

52 outer end portion

60 peripheral ring

61 joining part

61A rivet joint

62 flange part

62A inclined abutting part

63 step part

Center of rotation of C

Forward dumping position of Pa

Locking position of Pb primary

Pc backward dump position

Angle of Pd trunk

K mesh point

R push point

And (4) an S gap.

Claims

1. A vehicle seat reclining device is provided with:

a pawl supported from both sides in a rotational direction by a pair of guide walls provided to the guide, and engaged with the ratchet by being pushed to an outer side in a radial direction, to restrict relative rotation of the ratchet and the guide; and

a cam that pushes the pawl from an inner side to an outer side in a radial direction,

the pawl has: an eccentric structure that is pressed and inclined to one side in the rotational direction between the pair of guide walls by an urging force received from the cam; and a first protrusion protruding from a side surface of one side of the pawl in the rotation direction and restricting inclination of the pawl by contact with the guide wall facing thereto.

2. The reclining device of a vehicle seat according to claim 1,

3. The reclining device of a vehicle seat according to claim 2,

the second projection is located radially outward of the first projection.

4. The reclining device of a vehicle seat according to claim 2 or 3,

the pawl has: a main body surface portion that receives a pressing force from an inner side in a radial direction by the cam; and an offset surface portion having a shape that is pushed out from the main body surface portion in an axial direction in a half-blanking shape, and arranged in parallel with the cam in the axial direction,

the second protrusion has the following shape: the inclined surface of the second projection extends over at least the entire area of the main body surface portion in the side surface on the other side in the rotational direction of the pawl.

5. The reclining device of a vehicle seat according to any one of claims 1 to 4,

the vehicle seat reclining device is provided with a plurality of pawls,

a particular one of the plurality of detents has the first protrusion.

6. The reclining device of a vehicle seat according to any one of claims 1 to 5,

the first protrusion has the following shape: the inclined surface of the first protrusion extends over at least the entire area of the main body surface portion in the side surface on the one side in the rotational direction of the pawl.

7. A vehicle seat reclining device is provided with:

a pawl supported from both sides in a rotational direction by a pair of guide walls provided to the guide, and engaged with the ratchet by being pushed to an outer side in a radial direction, to restrict relative rotation of the ratchet and the guide;

a cam that pushes the pawl from an inner side to an outer side in a radial direction;

an eccentric structure that presses the pawl between the pair of guide walls to one side in the rotational direction by a pressing force received from the cam and tilts the pawl; and

a first protrusion protruding from the guide wall facing a side surface on one side of the pawl in the rotation direction and restricting inclination of the pawl by contact with the pawl.

8. The reclining device of a vehicle seat according to claim 7,

the vehicle seat reclining device includes a second protrusion that protrudes from the guide wall facing the other side surface of the pawl in the rotation direction, and that restricts tilting of the pawl by contact with the pawl, thereby holding the pawl in a posture in which the pawl contacts both of the pair of guide walls.

9. The reclining device of a vehicle seat according to claim 8,

the second protrusion has the following shape: the inclined surface of the second projection extends over the entire area of the side surface of the guide wall that faces the pawl.

10. The reclining device of a vehicle seat according to any one of claims 7 to 9,

the first protrusion has the following shape: the inclined surface of the first projection extends over the entire area of the side surface of the guide wall that faces the pawl.