JP2020104628A

JP2020104628A - Reclining device for vehicle seat

Info

Publication number: JP2020104628A
Application number: JP2018243884A
Authority: JP
Inventors: 大庭　徹也; Tetsuya Oba; 徹也大庭; 俊裕彦坂; Toshihiro Hikosaka; 知恵子奥山; Chieko Okuyama
Original assignee: TF Metal Co Ltd
Current assignee: TF Metal Co Ltd
Priority date: 2018-12-27
Filing date: 2018-12-27
Publication date: 2020-07-09

Abstract

To provide a reclining device which shows increased locking strength in engagement by improving entering properties of an external tooth and an internal tooth in the engagement.SOLUTION: A tooth member 5 is rotatably supported by a base member 4. Three locking members 11, 12, 13 are arranged at trisected positions as main elements of a locking mechanism 10. The locking members 11 to 13 are guided by guiding parts 16 to 21 on a side of the base member 4 and are in a locked state as an external tooth 22 and an inner tooth 9 are meshed in accordance with rotations of a cam 14. The first locking member 11 is arranged within a range of a rotation clearance α in a direction where the tooth member 5 is biased. Guide surfaces 18a, 19a, 20a, 21a, respectively guiding the second and third locking members 12, 13 are formed by shifting in a direction where the tooth member 5 is biased by a biased amount β that is slightly larger than the sum of a slide clearance γ and rotation clearance α.SELECTED DRAWING: Figure 3

Description

本発明は、車両用シートのリクライニング装置に関し、特に乗員の座部となるシートクッションに対して背もたれ部となるシートバックを傾動変位可能に支持するリクライニング装置に関する。 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle seat reclining device, and more particularly to a reclining device that tiltably displaces a seat back that serves as a backrest portion with respect to a seat cushion that serves as a seat portion of an occupant.

この種の車両用シートのリクライニング装置には、シートクッション側となるベース部材に対してシートバック側となるツース部材とが回転可能に支持されていて、ベース部材とツース部材との間に、複数のロック部材とカムを主要素とするロック機構が収容配置されているものがある。 In this type of vehicle seat reclining device, a seat cushion side tooth member is rotatably supported with respect to a seat cushion side base member, and a plurality of seat member side tooth members are provided between the base member and the tooth member. There is a device in which a lock mechanism having a lock member and a cam as main elements is housed and arranged.

そして、ベース部材のガイド部に沿って径方向に移動可能なロック部材をカムにて外側に押し出し、ツース部材内歯にロック部材の外歯を噛み合わせることで、ベース部材に対するツース部材の回転をロックするようになっている。 Then, the lock member that is movable in the radial direction along the guide portion of the base member is pushed outward by the cam, and the outer teeth of the lock member are meshed with the inner teeth of the tooth member, thereby rotating the tooth member with respect to the base member. It is supposed to lock.

このような構造では、ロック部材とガイド部との間にロック部材の摺動に必要な隙間が不可避的に存在し、この隙間はロック時におけるベース部材とツース部材との間の「がたつき」の原因となる。そのため、従来から、ロック時には上記隙間をなくして「がたつき」を防止するための構造が提案されている。 In such a structure, a gap necessary for sliding the lock member is inevitably present between the lock member and the guide portion, and this gap causes “rattle” between the base member and the tooth member at the time of locking. Will cause Therefore, conventionally, there has been proposed a structure for preventing the “rattle” by eliminating the above-mentioned gap at the time of locking.

例えば特許文献１には、１２０度間隔で配置した三つのロック部材を、それぞれ歯のピッチαに対してα／３だけずらせて配置し、ロック時には、各ロック部材の外歯をツース部材の内歯に噛み合わせながら、二つのロック部材を傾動変位させて、これら二つのロック部材が当該ロック部材をガイドずるガイド部（扇形部材）の一つに互いに逆方向から挟み込むように接することで、回転方向の「がたつき」を防止するようにした構造のものが開示されている（特許文献１の図４参照）。なお、特許文献１以外にも、類似の構造が特許文献２，３等に開示されている。 For example, in Patent Document 1, three lock members arranged at intervals of 120 degrees are arranged by being shifted by α/3 with respect to the tooth pitch α, and when locked, the outer teeth of each lock member are arranged inside the tooth member. While engaging with teeth, the two lock members are tilted and displaced, and these two lock members come into contact with one of the guide parts (fan-shaped members) that guide the lock members so as to sandwich them from opposite directions, thereby rotating. A structure having a structure for preventing “rattle” in the direction is disclosed (see FIG. 4 of Patent Document 1). In addition to Patent Document 1, similar structures are disclosed in Patent Documents 2 and 3.

特公平５−６４４７号公報Japanese Patent Publication No. 5-6447 特開平１１−１５５６７３号公報JP, 11-155673, A 特開２０１２−２２４０１号公報JP 2012-22401 A

しかしながら、シートクッション側となるベース部材（固定フランジ）の内周面にシートバック側となるツース部材（可動フランジ）の歯付環が内接するかたちで回転可能に支持されていて、両者の間には相対回転のための隙間が不可避的に存在している。この回転部での隙間の存在に起因して、ロック解除時には、シートバックの自重やシートバックを前倒れ方向に付勢するリターンばね力の影響を受けて、ベース部材とツース部材とが芯ずれを生じ、ベース部材に対してツース部材が上記隙間の範囲内で片寄った状態となる。 However, the toothed ring of the tooth member (movable flange) on the seat back side is rotatably supported in an inscribed manner on the inner peripheral surface of the base member (fixed flange) on the seat cushion side. Unavoidably has a gap for relative rotation. Due to the existence of the gap in the rotating portion, when the lock is released, the base member and the tooth member are misaligned under the influence of the weight of the seat back and the return spring force that biases the seat back in the forward tilt direction. Occurs, and the tooth member is offset from the base member within the range of the gap.

このツース部材の片寄りの影響を受けて、ロック解除状態からロック状態に移行する際に、ロック部材の外歯がツース部材の内歯ギヤに噛み合う際の進入性が悪く、外歯と内歯の噛み合いが不十分となることがあり、外歯と内歯の噛み合い強度、ひいてはロック状態での強度（ロック強度）が低下するおそれある。そのため、従来は、カムをロック方向に付勢するロックばねのばね力をより強くして外歯と内歯とが十分に噛み合うようにしているが、ロック解除の操作力が重くなるという問題がある。 When shifting from the unlocked state to the locked state under the influence of the deviation of the tooth member, the external teeth of the lock member have poor penetration when meshing with the internal gear of the tooth member, and May be insufficiently meshed, and the meshing strength between the outer teeth and the inner teeth, and eventually the strength in the locked state (lock strength), may be reduced. Therefore, conventionally, the spring force of the lock spring for urging the cam in the locking direction is further strengthened so that the outer teeth and the inner teeth are sufficiently meshed with each other, but the operation force for unlocking becomes heavy. is there.

また、特許文献１の図４に開示された構造では、上方側に配置された一つのロック部材は、両側のガイド部（扇形部材）との間に隙間を有していると共に、先に説明したように、ベース部材（固定フランジ）とツース部材（可動フランジ）の歯付環との間には、両者の相対回転のための隙間が不可避的に存在している。 Further, in the structure disclosed in FIG. 4 of Patent Document 1, one lock member arranged on the upper side has a gap between the guide portions (fan-shaped members) on both sides, and is described above. As described above, a gap for relative rotation between the base member (fixed flange) and the toothed ring of the tooth member (movable flange) is unavoidably present.

そのため、例えばシートバックを前後方向に押した際に、上記隙間の総和の範囲内で、二つのロック部材で挟まれているガイド部（扇形部材）を支点としてツース部材、ひいてはシートバックが回転変位することになり、ロック状態でシートバック側のツース部材の剛性感が低いという問題がある。 Therefore, for example, when the seat back is pushed in the front-rear direction, the tooth member, and eventually the seat back, is rotationally displaced within the range of the total of the above-mentioned gaps with the guide portion (fan-shaped member) sandwiched by the two lock members as the fulcrum. As a result, there is a problem in that the feeling of rigidity of the tooth member on the seat back side is low in the locked state.

本発明は、このような課題に着目してなされたものであり、外歯ギヤと内歯ギヤの噛み合い時の進入性を良くして噛み合い時のロック強度を高めると共に、ロック状態でのシートバック側のツース部材の剛性感の向上を図ったリクライニング装置を提供するものである。 The present invention has been made in view of such a problem, and improves the entry property at the time of meshing of the external gear and the internal gear to enhance the lock strength at the time of meshing, and the seat back in the locked state. It is intended to provide a reclining device for improving the rigidity of the tooth member on the side.

本発明は、シートクッション側に配置されるベース部材と、シートバック側に配置されて、前記ベース部材側を軸穴とする軸支持部に回転可能に軸支持されると共に、その回転中心と同心状の内歯を有するツース部材と、ロック機構と、をを備えた車両用シートのリクライニング装置である。 According to the present invention, a base member arranged on the seat cushion side and a base member arranged on the seat back side are rotatably shaft-supported by a shaft support portion having the base member side as a shaft hole, and are concentric with the rotation center thereof. A reclining device for a vehicle seat, comprising a tooth member having a toothed inner tooth and a lock mechanism.

前記ロック機構は、前記ツース部材の回転中心周りに約１２０度間隔で配置される共に、前記ベース部材に設けられたガイド部によってそれぞれ半径方向に移動可能にガイドされていて、前記内歯と噛み合い係合可能な外歯を有する三つのロック部材と、前記三つのロック部材を、前記内歯と前記外歯とを噛み合い係合部として前記ツース部材に係合離脱させるカム部材と、このカム部材を前記内歯と前記外歯とが噛み合い係合するロック方向に向けて付勢するロックばねと、から構成される。 The lock mechanism is arranged around the rotation center of the tooth member at intervals of about 120 degrees, and is guided by guide portions provided on the base member so as to be movable in the radial direction, and meshes with the internal teeth. Three lock members having outer teeth that can be engaged, a cam member that engages and disengages the three lock members with the tooth member as meshing engagement portions of the inner teeth and the outer teeth, and the cam members. A lock spring for urging the inner tooth and the outer tooth in a locking direction in which the inner tooth and the outer tooth engage with each other.

その上で、前記三つのロック部材のうち第１のロック部材は、前記シートバックに作用する力により前記軸支持部の回転隙間の範囲内で前記ツース部材が片寄る方向の向きで配置されていて、前記三つのロック部材のうち第２，第３のロック部材をガイドする前記ガイド部のガイド面は、当該ガイド面での摺動隙間と前記回転隙間との和よりもわずかに大きい量だけ前記ツース部材の片寄り方向にずらせて形成されていることを特徴とする。 In addition, the first locking member of the three locking members is arranged in a direction in which the tooth member is biased within the range of the rotation gap of the shaft support portion by the force acting on the seat back. The guide surface of the guide portion that guides the second and third lock members of the three lock members is an amount that is slightly larger than the sum of the sliding clearance and the rotation clearance on the guide surface. It is characterized in that the tooth member is formed so as to be offset in one direction.

より具体的な態様としては、請求項２に記載のように、前記三つのロック部材は、それぞれに当該ロック部材を両側から挟み込む一対のガイド面によって前記半径方向に移動可能にガイドされていて、前記第２，第３のロック部材をガイドする各一対のガイド面は、前記ツース部材の片寄り方向にずらせて形成されている。 As a more specific aspect, as described in claim 2, the three lock members are guided movably in the radial direction by a pair of guide surfaces that sandwich the lock member from both sides, respectively. The pair of guide surfaces that guide the second and third lock members are formed so as to be displaced in the direction toward one side of the tooth member.

シートバックに負荷される荷重を考慮した態様としては、請求項３に記載のように、前記ベース部材と前記ツース部材との間に、前記シートクッションに対して前記シートバックを前倒し方向に付勢するリターンばねを備えていて、前記第１のロック部材は、前記軸支持部の回転隙間の範囲内で、前記リターンばねの付勢力により前記ツース部材が片寄る方向の向きで配置されている。 As a mode in which the load applied to the seat back is taken into consideration, the seat back is biased in the forward tilting direction with respect to the seat cushion between the base member and the tooth member as described in claim 3. The first lock member is arranged in a direction in which the tooth member is biased by the urging force of the return spring within the rotation gap of the shaft support portion.

シートバックに負荷される荷重を考慮した別の態様としては、請求項４に記載のように、前記軸支持部では前記ベース部材側を軸穴とし前記ツース部材側を軸とする回転対偶の関係となっている共に、前記シートクッションの重さにより前記軸穴の内周面の上部側に前記回転隙間を有していて、前記第１のロック部材は、前記回転隙間の最大位置とは反対側の下方位置に配置されている。 As another aspect in consideration of the load applied to the seat back, as described in claim 4, in the shaft support portion, a relationship of a rotational pair in which the base member side is the shaft hole and the tooth member side is the shaft. In addition, due to the weight of the seat cushion, the rotation gap is provided on the upper side of the inner peripheral surface of the shaft hole, and the first lock member is opposite to the maximum position of the rotation gap. It is arranged at the lower position on the side.

前記第２，第３のロック部材をガイドする前記ガイド部のガイド面の具体的形態としては、請求項５に記載のように、前記第２，第３のロック部材をガイドする各一対のガイド面は、前記三つのロック部材を約１２０度間隔の配置とした場合の一方のガイド面の位置に対して、前記ツース部材の片寄り方向に平行にずらせて形成されている。 As a specific form of the guide surface of the guide portion that guides the second and third lock members, as described in claim 5, a pair of guides that guide the second and third lock members. The surface is formed so as to be displaced parallel to the offset direction of the tooth member with respect to the position of one guide surface when the three lock members are arranged at intervals of about 120 degrees.

シートバックの前後方向での剛性感を高める上で望ましい態様としては、請求項６に記載のように、前記ベース部材の外周部に半抜き加工により前記軸支持部が円環状に形成されていて、この軸支持部の内周面を軸穴として円形の前記ツース部材の外周面が回転可能に支持されていると共に、前記軸支持部の内周面のうち前記ツース部材の片寄り位置に凹部が形成されている。 As a desirable mode for enhancing the rigidity of the seat back in the front-rear direction, the shaft support portion is formed in an annular shape by half blanking on the outer peripheral portion of the base member as described in claim 6. The outer peripheral surface of the circular tooth member is rotatably supported by using the inner peripheral surface of the shaft supporting portion as a shaft hole, and the inner peripheral surface of the shaft supporting portion is recessed at a position offset to the tooth member. Are formed.

シートバックの前後方向でのさらなる剛性感を高める上で望ましい態様としては、請求項７に記載のように、前記第１のロック部材と、当該第１のロック部材をガイドする前記ガイド部のガイド面との間に、前記第１のロック部材の姿勢を矯正する姿勢矯正機構が設けられている。 As a desirable mode in order to further enhance the sense of rigidity in the front-back direction of the seat back, as described in claim 7, the guide of the first lock member and the guide portion that guides the first lock member. A posture correcting mechanism for correcting the posture of the first lock member is provided between the surface and the surface.

より具体的な態様としては、請求項８に記載のように、前記第１のロック部材の外歯は、その歯先円の円弧の中心が第１のロック部材を幅方向で二分する中心線に対して左右方向でずれた位置に設定されていて、前記内歯と前記外歯とが噛み合い係合するロック状態において、前記第１のロック部材が前記ガイド面に対して傾き、当該第１のロック部材の対角方向の二箇所で前記ガイド面に接するようになっている。 As a more specific aspect, as described in claim 8, the center line of the arc of the tip circle of the outer tooth of the first lock member divides the first lock member into two in the width direction. In a locked state in which the inner teeth and the outer teeth are meshed and engaged with each other, the first lock member tilts with respect to the guide surface, and The two lock members are in contact with the guide surface at two diagonal positions.

したがって、本発明では、前記軸支持部での回転隙間のほか、第２，第３のロック部材をガイドするガイド面での摺動隙間の影響を回避できるようになる。 Therefore, according to the present invention, it is possible to avoid the influence of the rotation gap in the shaft support portion and the sliding gap in the guide surfaces that guide the second and third lock members.

本発明によれば、三つのロック部材のうち第１のロック部材は、軸支持部の回転隙間の範囲内でツース部材が片寄る方向の向きで配置されていて、その片寄り方向の位置では上記回転隙間がない状態となる。そのため、ロック状態およびロック解除状態においても上記片寄り状態が維持され、第１のロック部材はこの片寄り方向に移動することになり、内歯と外歯との噛み合い時の進入性が良く、両者の噛み合いが不十分となることがない。 According to the present invention, the first lock member of the three lock members is arranged in a direction in which the tooth member is offset within the range of the rotation gap of the shaft support portion, and at the position in the offset direction, There is no rotation gap. Therefore, the offset state is maintained even in the locked state and the unlocked state, and the first lock member moves in the offset direction, which facilitates the entry when the internal teeth and the external teeth are engaged, The engagement between the two does not become insufficient.

また、第２，第３のロック部材をガイドする前記ガイド部のガイド面は、上記片寄り方向と同じ方向にずらせて形成されているので、ロック時には、第２，第３のロック部材もまた余分な動きをすることなく径方向に移動することになり、内歯と外歯との噛み合い時の進入性が良く、両者の噛み合いが不十分となることがない。その結果、ツース部材の内歯と三つのロック部材の外歯との噛み合い強度、ひいてはロック状態での強度（ロック強度）が向上する。また、必要となるロックばねのばね力を弱くできるため、カムをロック解除方向へ操作する際の操作力を下げることができる。 Further, since the guide surfaces of the guide portions that guide the second and third lock members are formed so as to be displaced in the same direction as the above-mentioned offset direction, the second and third lock members also move when locked. Since it moves in the radial direction without extra movement, the inner teeth and the outer teeth have good penetration when meshing with each other, and the meshing of the two does not become insufficient. As a result, the meshing strength between the inner teeth of the tooth member and the outer teeth of the three lock members, and thus the strength in the locked state (lock strength), is improved. Moreover, since the required spring force of the lock spring can be weakened, the operating force when operating the cam in the unlocking direction can be reduced.

さらに、第２，第３のロック部材をガイドするガイド面の第１のロック部材側への片寄り量（片寄り方向へのずれ量）は、該当するガイド面での摺動隙間と上記回転隙間との和よりもわずかに大きい量に設定されている。そのため、第２，第３のロック部材が上記ガイド面で拘束されて径方向にのみ移動し、ロック状態では第２，第３のロック部材の外歯とツース部材の内歯とがいわゆるハーフロック状態となるので、いわゆる「がた詰め」効果によりツース部材の回転方向およびツース部材の片寄り方向への移動を防止できる。 Further, the amount of deviation of the guide surfaces that guide the second and third lock members toward the first lock member (the amount of deviation in the direction of deviation) is determined by the sliding clearance on the corresponding guide surface and the rotation described above. The amount is set to be slightly larger than the sum of the gap. Therefore, the second and third lock members are constrained by the guide surface and move only in the radial direction, and in the locked state, the outer teeth of the second and third lock members and the inner teeth of the tooth member are so-called half locks. Since it is in the state, it is possible to prevent the tooth member from moving in the rotation direction and the tooth member in the one-sided direction due to the so-called “rattle” effect.

加えて、上記第２，第３のロック部材の外歯とツース部材の内歯とのいわゆるハーフロック状態となる噛み合いは、先に述べたように、第２，第３のロック部材をガイドするガイド面の第１のロック部材側への片寄り量（片寄り方向へのずれ量）に起因して生ずる。その一方で、上記片寄り量は例えば特許文献１に開示されているところの歯のピッチαの１／３に比べて十分に小さくすることができるから、いわゆるハーフロック状態でありながら外歯と内歯との噛み合い深さを大きく確保できる。その結果、第２，第３のロック部材の外歯とツース部材の内歯との噛み合い強度、ひいてはロック状態での強度（ロック強度）が一段と向上する。 In addition, the meshing of the outer teeth of the second and third lock members and the inner teeth of the tooth member in a so-called half-lock state guides the second and third lock members, as described above. It occurs due to the amount of deviation of the guide surface toward the first lock member (the amount of deviation in the direction of deviation). On the other hand, the offset amount can be made sufficiently smaller than, for example, 1/3 of the tooth pitch α disclosed in Patent Document 1, so that it is possible to reduce the deviation from the external teeth even in the so-called half-locked state. A large engagement depth with the internal teeth can be secured. As a result, the meshing strength between the outer teeth of the second and third lock members and the inner teeth of the tooth member, and thus the strength in the locked state (lock strength), is further improved.

本発明に係るリクライニング装置の第１の実施の形態を示す図で、シートクッション側のベースブラケットとシートバック側のアームブラケットとの間に介装されたリクライニング装置の概略説明図。FIG. 1 is a diagram showing a first embodiment of a reclining device according to the present invention, and is a schematic explanatory view of a reclining device interposed between a seat cushion side base bracket and a seat back side arm bracket. 図１のＡ−Ａ線に沿った断面図。Sectional drawing which followed the AA line of FIG. 図１に示したリクライニング装置の拡大図で、図２のＢ−Ｂ線に沿った断面図。FIG. 3 is an enlarged view of the reclining device shown in FIG. 1 and is a cross-sectional view taken along line BB of FIG. 2. 本発明に係るリクライニング装置の第２の実施の形態を示す図で、図１と同じ状態での概略説明図。It is a figure which shows 2nd Embodiment of the reclining device which concerns on this invention, and is a schematic explanatory drawing in the same state as FIG. 図４に示したリクライニング装置の拡大図で、図３と同じ状態の断面図。FIG. 4 is an enlarged view of the reclining device shown in FIG. 4 and is a cross-sectional view in the same state as in FIG. 3. 本発明に係るリクライニング装置の第３の実施の形態を示す図で、図１と同じ状態の断面図。FIG. 3 is a view showing a third embodiment of the reclining device according to the present invention, and is a cross-sectional view in the same state as in FIG. 1. 本発明に係るリクライニング装置の第４の実施の形態を示す図で、第１のロック部材のロック時の挙動を示す説明図。It is a figure which shows 4th Embodiment of the reclining device which concerns on this invention, and is explanatory drawing which shows the behavior at the time of a lock of a 1st locking member.

図１〜３は本発明に係る車両用シートのリクライニング装置を実施するためのより具体的な第１の実施の形態を示していて、図１はリクライニング装置を車両用シートの側面側から見た概略説明図を示し、図２は図１のＡ−Ａ線に沿った断面図を示している。また、図３は図１に示したリクライニング装置の拡大図で、図２のＢ−Ｂ線に沿った断面図を示している。 1 to 3 show a more specific first embodiment for implementing a reclining device for a vehicle seat according to the present invention, and FIG. 1 shows the reclining device from a side surface side of the vehicle seat. FIG. 2 shows a schematic explanatory view, and FIG. 2 shows a cross-sectional view taken along the line AA of FIG. 3 is an enlarged view of the reclining device shown in FIG. 1, showing a cross-sectional view taken along the line BB of FIG.

図１，２に示すように、ベースブラケット１とアームブラケット２とが後述する円盤状のリクライニング装置３を介して回転可能に連結されている。ベースブラケット１は図示を省略したシートクッション側のシートクッションフレームに、アームブラケット２は同じく図示を省略したシートクバック側のシートバックフレームにそれぞれ固定される。 As shown in FIGS. 1 and 2, a base bracket 1 and an arm bracket 2 are rotatably connected via a disc-shaped reclining device 3 described later. The base bracket 1 is fixed to a seat cushion frame on the seat cushion side (not shown), and the arm bracket 2 is fixed to a seat back frame on the seat back side (not shown).

図２，３に示すように、リクライニング装置３は、内部に後述するロック機構１０の各要素を収容配置すると共に、共に円形のベース部材４とツース部材５とを互いに平行となるように突き合わせた上で、両者の周縁部に配置される環状のホルダーリング６にロール曲げ加工を施すことによりユニット化されているものである。これにより、リクライニング装置３は全体として変形円盤状をなしていて、ベース部材４とツース部材５とが平行状態を保ったままで相対回転可能となっている。 As shown in FIGS. 2 and 3, the reclining device 3 accommodates and arranges the respective elements of the lock mechanism 10 described later, and the circular base member 4 and the tooth member 5 are butted so as to be parallel to each other. Above, the annular holder ring 6 arranged at the peripheral portions of both is roll-bent to be unitized. As a result, the reclining device 3 has a deformed disk shape as a whole, and is relatively rotatable while the base member 4 and the tooth member 5 are kept in a parallel state.

ベース部材４およびツース部材５の外側面には、半抜き印圧加工により複数個の位置決め突起部４ａまたは５ａがそれぞれに形成されている。そして、ベース部材４の位置決め突起部４ａとベースブラケット１の位置決め穴とを嵌合させた上で、その嵌合部分に溶接を施すことにより、ベース部材４とベースブラケット１とが一体化される。同様に、ツース部材５の位置決め突起部５ａとアームブラケット２の位置決め穴とを嵌合させた上で、その嵌合部分に溶接を施すことにより、ツース部材５とアームブラケット２とが一体化される。 A plurality of positioning protrusions 4a or 5a are formed on the outer surfaces of the base member 4 and the tooth member 5 by half-press printing. Then, the positioning protrusion 4a of the base member 4 is fitted into the positioning hole of the base bracket 1, and then the fitting portion is welded, whereby the base member 4 and the base bracket 1 are integrated. .. Similarly, the toothing member 5 and the arm bracket 2 are integrated by fitting the positioning protrusion 5a of the tooth member 5 and the positioning hole of the arm bracket 2 and then welding the fitting portion. It

その結果、ベースブラケット１と一体化されるベース部材４が固定側となり、アームブラケット２と一体化されるツース部材５が可動側として機能することになる。それ故に、リクライニング装置３だけに着目した場合には、固定側となるベース部材４に対してツース部材５が回転可能となっている。 As a result, the base member 4 integrated with the base bracket 1 becomes the fixed side, and the tooth member 5 integrated with the arm bracket 2 functions as the movable side. Therefore, when focusing on only the reclining device 3, the tooth member 5 is rotatable with respect to the base member 4 on the fixed side.

図２，３に示すように、ベース部材４の周縁部には、ツース部材５側に向かって突出しつつ径方向外側に張り出すように、円環状のアウタフランジ部７が一体に形成されている。このアウタフランジ部７が形成されていることによって、ベース部材４は円形の浅皿状のものとして形成されている。 As shown in FIGS. 2 and 3, a ring-shaped outer flange portion 7 is integrally formed on the peripheral portion of the base member 4 so as to project toward the tooth member 5 side and project outward in the radial direction. .. By forming the outer flange portion 7, the base member 4 is formed as a circular shallow dish.

同様に、ツース部材５の周縁部には、ベース部材４側に向かって突出しつつ径方向外側に張り出すように、円環状のインナフランジ部８が一体に形成されている。このインナフランジ部８が形成されていることによって、ツース部材５は円形の浅皿状のものとして形成されている。そして、ツース部材５のインナフランジ部８の内周面には全周にわたって内歯９が形成されていて、ツース部材５がいわゆるリングギヤとして機能するようになっている。 Similarly, an annular inner flange portion 8 is integrally formed on the peripheral edge portion of the tooth member 5 so as to project toward the base member 4 side and project outward in the radial direction. By forming the inner flange portion 8, the tooth member 5 is formed as a circular shallow dish. Inner teeth 9 are formed on the inner peripheral surface of the inner flange portion 8 of the tooth member 5 over the entire circumference so that the tooth member 5 functions as a so-called ring gear.

なお、図３に示すように、ツース部材５のインナフランジ部８の外径は、ベース部材４のアウタフランジ部７の内周にはまり得る大きさに設定されていて、ツース部材５のインナフランジ部８がベース部材４のアウタフランジ部７の内周側にはめ合わされた上で、双方のフランジ部７，８同士が相対回転可能なようにホルダーリング６で拘束されている。すなわち、ツース部材５は、ベース部材４のアウタフランジ部７側を軸穴として回転可能に軸支持されていて、ベース部材４のアウタフランジ部７はツース部材５のための軸支持部として機能する。また、図３では、ベース部材４のアウタフランジ部７とツース部材５のインナフランジ部８との相対位置関係の理解を容易にするために、アウタフランジ部７に代わってインナフランジ部８のみにハッチングを施している。 As shown in FIG. 3, the outer diameter of the inner flange portion 8 of the tooth member 5 is set to a size that can fit into the inner circumference of the outer flange portion 7 of the base member 4, and the inner flange portion of the tooth member 5 is formed. The portion 8 is fitted to the inner peripheral side of the outer flange portion 7 of the base member 4, and both flange portions 7 and 8 are restrained by the holder ring 6 so that they can rotate relative to each other. That is, the tooth member 5 is rotatably axially supported by using the outer flange portion 7 side of the base member 4 as a shaft hole, and the outer flange portion 7 of the base member 4 functions as a shaft supporting portion for the tooth member 5. .. Further, in FIG. 3, in order to facilitate understanding of the relative positional relationship between the outer flange portion 7 of the base member 4 and the inner flange portion 8 of the tooth member 5, only the inner flange portion 8 is used instead of the outer flange portion 7. It is hatched.

また、図２，３に示すように、ベース部材４と重ね合わされたツース部材５の内周には、ロック機構１０の構成要素として、三つのロック部材１１，１２，１３と、それら三つのロック部材１１，１２，１３が共有することになるカム部材としての単一のカム１４と、ロック部材１１，１２，１３と同数の三つのロックばね１５と、がそれぞれ収容配置されている。以下、ロック機構１０の詳細について説明する。 Further, as shown in FIGS. 2 and 3, on the inner circumference of the tooth member 5 superposed on the base member 4, three lock members 11, 12, 13 and the three locks are provided as constituent elements of the lock mechanism 10. A single cam 14 serving as a cam member shared by the members 11, 12, and 13 and three lock springs 15 of the same number as the lock members 11, 12, and 13 are respectively housed and arranged. Hereinafter, details of the lock mechanism 10 will be described.

図２，３に示すように、円形のベース部材４の内底面には、二つで対をなす三組の扇形状のガイド部１６，１７と１８，１９および２０，２１が突出形成されていて、これらのガイド部１６〜２１がツース部材５の内周側に突出している。これらの各ガイド部１６〜２１は、回転方向での位相が位置決め突起部４ａと合致しないように配置位置が選定されいると共に、位置決め突起部４ａと同様に半抜き印圧加工によって形成されている。そして、一対のガイド部１６，１７同士の間には第１のロック部材１１が配置され、同様に一対のガイド部１８，１９同士の間には第２のロック部材１２が配置されている。さらに、一対のガイド部２０，２１同士の間には第３のロック部材１３が配置されている。 As shown in FIGS. 2 and 3, on the inner bottom surface of the circular base member 4, three pairs of fan-shaped guide portions 16, 17 and 18, 19, 19 and 20, 21 which are paired with each other are formed to project. Then, these guide portions 16 to 21 project to the inner peripheral side of the tooth member 5. The positions of these guide portions 16 to 21 are selected so that the phase in the rotational direction does not match the positioning protrusion 4a, and they are formed by half blanking printing as in the positioning protrusion 4a. .. Then, the first lock member 11 is arranged between the pair of guide portions 16 and 17, and the second lock member 12 is similarly arranged between the pair of guide portions 18 and 19. Further, a third lock member 13 is arranged between the pair of guide portions 20 and 21.

これらの三つのロック部材１１，１２，１３は、ツース部材５の円周方向の略三等分位置に、すなわち図３に示すように、ツース部材５の回転中心周りに約１２０度間隔で放射状に移動可能に配置されている。そして、第１のロック部材１１に着目した場合には、その第１のロック部材１１の両側に位置する一対のガイド部１６，１７のガイド面１６ａ，１７ａによって、第１のロック部材１１が径方向に進退移動可能にガイドされている。 These three lock members 11, 12 and 13 are radially arranged at approximately three equal positions in the circumferential direction of the tooth member 5, that is, as shown in FIG. 3, at radial intervals of about 120 degrees around the rotation center of the tooth member 5. It is arranged to be movable. When focusing on the first lock member 11, the diameter of the first lock member 11 is determined by the guide surfaces 16a and 17a of the pair of guide portions 16 and 17 located on both sides of the first lock member 11. It is guided to move forward and backward in the direction.

これらの構造は、第２，第３のロック部材１２，１３についても同様であって、第２のロック部材１２は一対のガイド面１８ａ，１９ａによって、第３のロック部材１３は一対のガイド面２０ａ，２１ａによって、それぞれ径方向に進退移動可能にガイドされている。図２，３の例では、車両搭載状態において、第１のロック部材１１の進退移動方向が真下を指向するように設定されている。 These structures are the same for the second and third lock members 12 and 13, and the second lock member 12 has a pair of guide surfaces 18a and 19a, and the third lock member 13 has a pair of guide surfaces. The guides 20a and 21a are capable of moving forward and backward in the radial direction. In the examples of FIGS. 2 and 3, the forward/backward movement direction of the first lock member 11 is set so as to point right below in the vehicle mounted state.

第１〜第３のロック部材１１，１２，１３はいずれも略矩形状の同じ形状のものであって、ツース部材５の内歯９に対向する一辺部を外周面とし、それと反対側の一辺部を内周面とした場合に、第１〜第３のロック部材１１，１２，１３の外周面には、ツース部材５の内歯９と噛み合い可能な外歯２２がそれぞれに形成されている。したがって、第１〜第３のロック部材１１，１２，１３が径方向外側に押し出された時には、第１〜第３のロック部材１１，１２，１３の外歯２２がツース部材５の内歯９に噛み合うことになる。 All of the first to third lock members 11, 12, and 13 have substantially the same rectangular shape, and one side facing the inner teeth 9 of the tooth member 5 is an outer peripheral surface, and one side opposite to the outer peripheral surface. When the portion is the inner peripheral surface, the outer teeth 22 capable of meshing with the inner teeth 9 of the tooth member 5 are formed on the outer peripheral surfaces of the first to third lock members 11, 12, and 13, respectively. .. Therefore, when the first to third lock members 11, 12, 13 are pushed outward in the radial direction, the outer teeth 22 of the first to third lock members 11, 12, 13 are changed to the inner teeth 9 of the tooth member 5. Will be engaged.

また、図３に示したツース部材５の中心位置、すなわち第１〜第３のロック部材１１，１２，１３の配列の中央部には、それらの第１〜第３のロック部材１１，１２，１３を径方向に進退移動させるためのカム１４が回転可能に配置されている。カム１４は、ベース部材４とツース部材５とで挟まれることで回転可能に拘束されている。さらに、ツース部材５の内周のうち、ガイド部１６〜２１や第１〜第３のロック部材１１，１２，１３で占有されていない三箇所には、それぞれに渦巻きばねタイプのロックばね１５が配置されている。 Further, at the center position of the tooth member 5 shown in FIG. 3, that is, at the central portion of the arrangement of the first to third locking members 11, 12, 13, the first to third locking members 11, 12, A cam 14 for moving the 13 forward and backward in the radial direction is rotatably arranged. The cam 14 is rotatably restrained by being sandwiched between the base member 4 and the tooth member 5. Further, in the inner circumference of the tooth member 5, spiral spring type lock springs 15 are respectively provided at three positions which are not occupied by the guide portions 16 to 21 and the first to third lock members 11, 12, and 13. It is arranged.

カム１４の外周面の三等分位置には、第１〜第３のロック部材１１，１２，１３に対応した位置に、図３の頂部２３ａから時計回り方向に向かって半径が次第に小さくなるカム面２３が形成されている。また、カム１４の外周面であって隣り合うカム面２３，２３同士の間には、ロックばね１５の外端部を係止するための係止凹部２４がそれぞれ形成されている。カム１４は、図２に示すように、操作部材５０としての操作レバー５２と操作軸５１とが同軸上で一体に形成されていて、操作レバー５２の回転操作に伴って一体的に回転変位する。なお、操作部材として、カム１４のロック解除方向への移動に連動して三つのロック部材１１，１２，１３をロック解除位置である径方向内方へ移動させるカムプレートやカム突起を有していてもよい。 At the trisection position on the outer peripheral surface of the cam 14, the radius gradually decreases from the top portion 23a of FIG. 3 in the clockwise direction at positions corresponding to the first to third locking members 11, 12, and 13. A surface 23 is formed. Further, locking recesses 24 for locking the outer end of the lock spring 15 are formed between the adjacent cam surfaces 23, 23 on the outer peripheral surface of the cam 14, respectively. As shown in FIG. 2, the cam 14 has an operation lever 52 as an operation member 50 and an operation shaft 51 which are coaxially and integrally formed with each other. The cam 14 is integrally rotationally displaced as the operation lever 52 is rotated. .. It should be noted that the operation member includes a cam plate and a cam projection that move the three lock members 11, 12, and 13 inward in the radial direction, which is the unlocked position, in conjunction with the movement of the cam 14 in the unlocked direction. May be.

図２，３に示すように、ベース部材４の内底面の一部であって各ロックばね１５が配置された部分の中央部には、先に述べた各ガイド部１６〜２１の半抜き印圧加工と同じ要領で略半円状の係止突起部２５が突出形成されている。そして、各ロックばね１５の内端部が係止突起部２５に係止されている一方、各ロックばね１５の外端部がカム１４の各係止凹部２４に係止されている。そのため、各ロックばね１５のばね力により、カム１４が図３の反時計回り方向、すなわちロック方向に付勢されている。 As shown in FIGS. 2 and 3, a part of the inner bottom surface of the base member 4 in which the lock springs 15 are arranged has a central portion, and each of the guide portions 16 to 21 has a semi-blank stamp. A substantially semicircular locking protrusion 25 is formed in a protruding manner in the same manner as the pressure processing. The inner ends of the lock springs 15 are locked to the locking projections 25, while the outer ends of the lock springs 15 are locked to the locking recesses 24 of the cam 14. Therefore, the cam 14 is biased in the counterclockwise direction in FIG. 3, that is, in the lock direction by the spring force of each lock spring 15.

図３では、上記のようにカム１４が各ロックばね１５によりロック方向に付勢されいて、各カム面２３の頂部２３ａが第１〜第３のロック部材１１，１２，１３の内周面に接しているロック状態を示している。 In FIG. 3, the cam 14 is biased in the lock direction by the lock springs 15 as described above, and the top portions 23a of the cam surfaces 23 are located on the inner peripheral surfaces of the first to third lock members 11, 12, and 13. It shows the locked state in contact.

同図から明らかなように、各ロック部材１１，１２，１３の内周面（外歯２２とは反対側の面）は、ロック方向である反時計回り方向に向かって上り勾配で傾斜した作動面２６となっていて、この作動面２６に各カム面２３の頂部２３ａが当接している。そのため、第１〜第３のロック部材１１，１２，１３は、両側のガイド部１６，１７、１８，１９、２０，２１にそれぞれガイドされながら、カム１４により径方向外側に押し出されて、その外歯２２がツース部材５の内歯９に噛み合って、ロック状態を自己保持している。なお、図３から明らかなように、各カム面２３の頂部２３ａは、作動面２６のうち反時計回り方向側に片寄った位置に当接している。 As is clear from the figure, the inner peripheral surface (the surface opposite to the outer teeth 22) of each lock member 11, 12, 13 is actuated with an upward slope in the counterclockwise direction which is the lock direction. The top surface 23 a of each cam surface 23 is in contact with the operating surface 26. Therefore, the first to third lock members 11, 12, 13 are pushed radially outward by the cam 14 while being guided by the guide portions 16, 17, 18, 19, 19, 20, 21 on both sides, respectively. The outer teeth 22 mesh with the inner teeth 9 of the tooth member 5 to self-hold the locked state. As is clear from FIG. 3, the apex 23a of each cam surface 23 is in contact with the position of the operating surface 26, which is offset to the counterclockwise direction side.

また、図３に示すように、第２のロック部材１２をガイドしている両側のガイド面１８ａ，１９ａは、所定量βだけ反時計回り方向に、すなわち第１のロック部材１１に近付く方向に片寄らせるべく、意図的にずらせて形成されている。同様に、第３のロック部材１３をガイドしている両側のガイド面２０ａ，２１ａも、所定量βだけ時計回り方向に、すなわち第１のロック部材１１に近付く方向に片寄らせるべく、意図的にずらせて形成されている。ここでは、所定量βを片寄り量と定義する。 Further, as shown in FIG. 3, the guide surfaces 18a, 19a on both sides which guide the second lock member 12 are counterclockwise by a predetermined amount β, that is, in the direction approaching the first lock member 11. It is formed with a purposeful offset so as to be offset. Similarly, the guide surfaces 20a and 21a on both sides, which guide the third lock member 13, are intentionally biased in the clockwise direction by a predetermined amount β, that is, toward the first lock member 11. It is formed by shifting. Here, the predetermined amount β is defined as a deviation amount.

したがって、第１のロック部材１１と第２のロック部材１２とのなす角度、および第１のロック部材１１と第３のロック部材１３とのなす角度は、１２０度よりも片寄り量β分だけ小さい角度となっている。その一方、第２のロック部材１２と第３のロック部材１３とのなす角度は、１２０度よりも２×β分だけ大きい角度となっている。 Therefore, the angle formed by the first lock member 11 and the second lock member 12 and the angle formed by the first lock member 11 and the third lock member 13 are the offset amounts β from 120 degrees. It has a small angle. On the other hand, the angle formed by the second lock member 12 and the third lock member 13 is larger than 120 degrees by 2×β.

なお、片寄り量βを有するガイド面１９ａ，２０ａの位置の理解を容易にするため、図３に示すように、第１〜第３のロック部材１１，１２，１３を１２０度間隔で配置したと仮定した場合のガイド面の位置を基準として、ガイド面１９ａまたは２０ａが片寄り量β分だけ反時計回り方向または時計回り方向に片寄っている部分にハッチングを施してある。また、ガイド面１９ａ，２０ａに関して、片寄り量β分だけ反時計回り方向または時計回り方向に片寄る前と後では、両者は互いに平行である。 In order to facilitate understanding of the positions of the guide surfaces 19a and 20a having the deviation amount β, the first to third lock members 11, 12 and 13 are arranged at 120 degree intervals as shown in FIG. On the basis of the position of the guide surface on the assumption that the guide surface 19a or 20a is set as a reference, the portion of the guide surface 19a or 20a that is offset in the counterclockwise direction or the clockwise direction by the offset amount β is hatched. Further, with respect to the guide surfaces 19a and 20a, both are parallel to each other before and after being offset in the counterclockwise direction or the clockwise direction by the offset amount β.

ここで、第１のロック部材１１と両側のガイド部１６，１７のガイド面１６ａ，１７ａとの間、第２のロック部材１２と両側のガイド部１８，１９のガイド面１８ａ，１９ａとの間、および第３のロック部材１３と両側のガイド部２０，２１のガイド面２０ａ，２１ａとの間には、各ロック部材１１，１２，１３の進退移動に必要な微小な隙間γが存在している。図３では、その隙間γを誇張して描いていて、ここでは隙間γを摺動隙間と定義する。 Here, between the first lock member 11 and the guide surfaces 16a, 17a of the guide portions 16, 17 on both sides, and between the second lock member 12 and the guide surfaces 18a, 19a of the guide portions 18, 19 on both sides. , And between the third lock member 13 and the guide surfaces 20a, 21a of the guide portions 20, 21 on both sides, there is a minute gap γ required for the forward and backward movement of each lock member 11, 12, 13. There is. In FIG. 3, the gap γ is exaggeratedly drawn, and here, the gap γ is defined as a sliding gap.

また、ベース部材４の円環状のアウタフランジ部７とツース部材５の同じく円環状のインナフランジ部８とは回転対偶の関係にあって、両者の間にはツース部材５の回転動作に必要な微小な隙間αが存在している。図３では、その隙間αを誇張して描いていて、ここでは、微小な隙間αを回転隙間と定義する。 Further, the annular outer flange portion 7 of the base member 4 and the similarly annular inner flange portion 8 of the tooth member 5 are in a rotational pair relationship, and a rotational movement of the tooth member 5 is necessary between them. There is a minute gap α. In FIG. 3, the gap α is exaggeratedly drawn, and here, the minute gap α is defined as a rotation gap.

そして、ツース部材５にはシートバックの重量Ｆａが作用するため、微視的には、ベース部材４のアウタフランジ部７に対してツース部材５のインナフランジ部８が芯ずれを起こし、ベース部材４のアウタフランジ部７に対してツース部材５のインナフランジ部８が下方に片寄るかたちとなる。その結果、ベース部材４とツース部材５との間の回転隙間αは、図３に示すように、ベース部材４のアウタフランジ部７の内周において、上方側に片寄ったかたちで発生することになる。すなわち、図３の真上位置において回転隙間αが最大となっている一方で、同図の真下位置では回転隙間αが最小となって、アウタフランジ部７とインナフランジ部８とが隙間無く接している。 Since the weight Fa of the seat back acts on the tooth member 5, microscopically, the inner flange portion 8 of the tooth member 5 deviates from the outer flange portion 7 of the base member 4, and the base member The inner flange portion 8 of the tooth member 5 is offset downward with respect to the outer flange portion 7 of No. 4. As a result, as shown in FIG. 3, the rotational gap α between the base member 4 and the tooth member 5 is generated on the inner periphery of the outer flange portion 7 of the base member 4 while being offset toward the upper side. Become. That is, while the rotation gap α is maximum at the position directly above in FIG. 3, the rotation gap α is minimum at the position directly below in FIG. 3, and the outer flange portion 7 and the inner flange portion 8 are in contact with each other without any gap. ing.

このような点を考慮し、図３に示したガイド面１９ａ，２０ａ片寄り量βは、各ロック部材１１，１２，１３の進退移動に必要な摺動隙間γと、ベース部材４のアウタフランジ部７に対するツース部材５のインナフランジ部８の回転に必要な回転隙間αと、の和よりもわずかに大きい値に設定されている。 In consideration of such a point, the offset amounts β of the guide surfaces 19a and 20a shown in FIG. 3 are the sliding gap γ required for the forward and backward movement of the lock members 11, 12 and 13, and the outer flange of the base member 4. It is set to a value slightly larger than the sum of the rotational clearance α required for the rotation of the inner flange portion 8 of the tooth member 5 with respect to the portion 7.

したがって、このように構成されたリクライニング装置３において、図３に示すロック機構１０のロック状態では、各ロックばね１５で付勢されたカム１４が反時計回り方向に回転して、第１〜第３のロック部材１１，１２，１３をツース部材５の半径方向外側に押し出している。この場合において、カム１４のそれぞれの頂部２３ａは、対応する各ロック部材１１，１２，１３の作動面２６のうち、各ロック部材１１，１２，１３の幅寸法を二分する中心線の位置を超えて、その中心線よりも反時計回り方向寄りの片寄った位置に当接している。そして、カム１４により押し出された第１〜第３のロック部材１１，１２，１３は、その外歯２２がツース部材５の内歯９と噛み合い、ロック状態を自己保持している。 Therefore, in the reclining device 3 thus configured, in the locked state of the lock mechanism 10 shown in FIG. 3, the cams 14 biased by the lock springs 15 rotate in the counterclockwise direction, and the first to the first The lock members 11, 12, 13 of No. 3 are pushed outward in the radial direction of the tooth member 5. In this case, each top 23a of the cam 14 exceeds the position of the center line that bisects the width dimension of each lock member 11, 12, 13 on the operating surface 26 of the corresponding lock member 11, 12, 13. And abuts on a position offset from the center line in the counterclockwise direction. The outer teeth 22 of the first to third lock members 11, 12, and 13 pushed out by the cam 14 mesh with the inner teeth 9 of the tooth member 5, and self-holds the locked state.

なお、図３に示したロック状態において、第１〜第３のロック部材１１，１２，１３の作動面２６のうち片寄った位置にカム１４の頂部２３ａが当接してはいても、作動面２６が反時計回り方向に向かって上り勾配の傾斜面となっているので、第１〜第３のロック部材１１，１２，１３が常にロック方向に向かって押されていて、カム１４の頂部２３ａが第１〜第３のロック部材１１，１２，１３の作動面２６から外れてしまうことはない。 Note that, in the locked state shown in FIG. 3, even if the top portion 23a of the cam 14 is in contact with the offset position of the operating surfaces 26 of the first to third locking members 11, 12, 13, even if the operating surface 26 is in contact. Is an inclined surface having an upward slope in the counterclockwise direction, so that the first to third locking members 11, 12, and 13 are constantly pushed in the locking direction, and the top portion 23a of the cam 14 is It does not come off from the operating surface 26 of the first to third locking members 11, 12, 13.

図３に示したロック状態において、先に述べたように、シートバックの重量の影響を受けて、ベース部材４のアウタフランジ部７に対してツース部材５のインナフランジ部８が下方に片寄っていて、ツース部材５のインナフランジ部８の上方側に回転隙間αが生じている。このような片寄り状態は、ロック機構１０がロック状態であるかロック解除状態（アンロック状態）であるかにかかわらず維持される。 In the locked state shown in FIG. 3, as described above, the inner flange portion 8 of the tooth member 5 is offset downward from the outer flange portion 7 of the base member 4 due to the influence of the weight of the seat back. As a result, a rotation gap α is formed above the inner flange portion 8 of the tooth member 5. Such an offset state is maintained regardless of whether the lock mechanism 10 is in the locked state or the unlocked state (unlocked state).

そのため、第１のロック部材１１に着目した場合、第１のロック部材１１の進退移動方向は、ベース部材４に対するツース部材５の片寄り方向に一致していて、ロック時には、第１のロック部材１１は上記片寄り方向に移動して、その外歯２２が内歯９に噛み合うことになる。したがって、第１のロック部材１１の外歯２２と内歯９との噛み合いに際して、上記回転隙間αが影響を及ぼすことはない。 Therefore, when focusing on the first lock member 11, the forward/backward movement direction of the first lock member 11 coincides with the offset direction of the tooth member 5 with respect to the base member 4, and the first lock member 11 is locked. 11 moves in the one-sided direction, and its outer teeth 22 mesh with the inner teeth 9. Therefore, when the outer teeth 22 and the inner teeth 9 of the first lock member 11 mesh with each other, the rotation gap α does not affect.

また、第２，第３のロック部材１２，１３に着目した場合、それぞれのガイド面１９ａ，２０ａがベース部材４に対するツース部材５の片寄り方向に所定量βだけ予めずらせて形成されているので、第２，第３のロック部材１２，１３の外歯２２を内歯９に噛み合わせる際に、第２，第３のロック部材１２，１３を進退移動方向以外に移動させる必要がなく、外歯２２と内歯９との噛み合いに際して、双方の歯同士の相対進入動作がスムーズに行われる。 Further, when focusing on the second and third lock members 12 and 13, since the respective guide surfaces 19a and 20a are formed by being displaced by a predetermined amount β in advance in the offset direction of the tooth member 5 with respect to the base member 4. When engaging the outer teeth 22 of the second and third lock members 12 and 13 with the inner teeth 9, there is no need to move the second and third lock members 12 and 13 in directions other than the forward/backward movement direction. When the teeth 22 and the inner teeth 9 are meshed with each other, the relative approaching motion of both teeth is smoothly performed.

この場合において、第２，第３のロック部材１２，１３をガイドするガイド面１９ａ，２０ａの片寄り量（片寄り方向へのずれ量）βは、上記摺動隙間γと回転隙間αとの和よりもわずかに大きい量に設定されている。そのため、第２，第３のロック部材１２，１３がガイド面１９ａ，２０ａで拘束されて径方向外側に向かって移動し、ロック状態では第２，第３のロック部材１２，１３の外歯２２とツース部材５の内歯９とがハーフロック状態となるので、いわゆる「がた詰め」効果によりツース部材５の回転方向およびツース部材５の片寄り方向への移動を防止できる。 In this case, the deviation amount (deviation amount in the deviation direction) β of the guide surfaces 19a and 20a that guide the second and third lock members 12 and 13 is the difference between the sliding clearance γ and the rotation clearance α. The amount is set slightly larger than the sum. Therefore, the second and third lock members 12 and 13 are constrained by the guide surfaces 19a and 20a and move radially outward, and in the locked state, the outer teeth 22 of the second and third lock members 12 and 13 are formed. Since the inner teeth 9 of the tooth member 5 are in a half-locked state, it is possible to prevent the tooth member 5 from moving in the rotational direction and the tooth member 5 in the one-sided direction due to a so-called “rattle filling” effect.

また、第２，第３のロック部材１２，１３の外歯２２とツース部材５の内歯９とがハーフロック状態となる噛み合いは、ガイド面１９ａ，２０ａの第１のロック部材１１側への片寄り量（片寄り方向へのずれ量）βに起因して生ずる。その一方で、上記片寄り量βは、例えば特許文献１に開示されているところの歯のピッチαの１／３に比べて十分に小さくすることができるから、ハーフロック状態でありながら外歯２２と内歯９との噛み合い深さを大きく確保できるようになる。その結果として、第２，第３のロック部材１２，１３の外歯２２とツース部材５の内歯９との噛み合い強度、ひいてはロック状態での強度（ロック強度）が一段と向上することになる。 In addition, the outer teeth 22 of the second and third lock members 12 and 13 and the inner teeth 9 of the tooth member 5 are meshed with each other in a half-locked state so that the guide surfaces 19a and 20a move toward the first lock member 11 side. It occurs due to the deviation amount (deviation amount in the deviation direction) β. On the other hand, the offset amount β can be made sufficiently smaller than, for example, 1/3 of the tooth pitch α disclosed in Patent Document 1, so that the external teeth are retained even in the half-locked state. It is possible to secure a large engagement depth between the inner teeth 22 and the inner teeth 9. As a result, the meshing strength between the outer teeth 22 of the second and third lock members 12 and 13 and the inner teeth 9 of the tooth member 5, and thus the strength in the locked state (lock strength), is further improved.

第２，第３のロック部材１２，１３に着目した場合のより詳細な挙動は次の通りである。図３に基づいて先に説明したように、第２，第３のロック部材１２，１３は、カム１４の頂部２３ａによって片寄った方向から押されるので、外歯２２の一部がツース部材５の内歯９に噛み合うと、内歯９側からの反力Ｆ１が生ずる。この反力Ｆ１を受けて、第２のロック部材１２は反時計回り方向に片寄っているガイド面１９ａに、第３のロック部材１３は時計回り方向に片寄っているガイド面２０ａにそれぞれ押し付けられる。 The more detailed behavior when paying attention to the second and third lock members 12 and 13 is as follows. As described above with reference to FIG. 3, since the second and third lock members 12 and 13 are pushed by the top portion 23a of the cam 14 from the offset direction, a part of the external teeth 22 of the tooth member 5 is removed. When meshing with the inner teeth 9, a reaction force F1 from the inner teeth 9 side is generated. Upon receiving this reaction force F1, the second lock member 12 is pressed against the guide surface 19a that is offset in the counterclockwise direction, and the third lock member 13 is pressed against the guide surface 20a that is offset in the clockwise direction.

それと同時に、ガイド面１９ａ側から第２のロック部材１２を押し返す反力Ｆ２が、ガイド面２０ａ側から第３のロック部材１３を押し返す反力Ｆ２がそれぞれ生ずる。この反力Ｆ２は、第２のロック部材１２を他方のガイド面１８ａに、第３のロック部材１３を同じく他方のガイド面２１ａに押し付ける力にほかならない。そのため、内歯９に押し付けられている第２，第３のロック部材１２，１３は、同時に、先に述べた摺動隙間γをなくすべく（いわゆる「がた詰め」）に他方のガイド面１８ａまたは２１ａに向かって押し付けられて、最終的には両側のガイド面１８ａ，１９ａまたは２０ａ，２１ａによって拘束されることになる。この状態が先に述べたハーフロック状態である。 At the same time, a reaction force F2 that pushes back the second lock member 12 from the guide surface 19a side, and a reaction force F2 that pushes back the third lock member 13 from the guide surface 20a side, respectively. This reaction force F2 is nothing but the force that presses the second lock member 12 against the other guide surface 18a and the third lock member 13 against the other guide surface 21a. Therefore, the second and third lock members 12 and 13 pressed against the inner teeth 9 are simultaneously guided by the other guide surface 18a in order to eliminate the above-mentioned sliding gap γ (so-called “rattle”). Alternatively, it is pressed toward 21a and finally constrained by the guide surfaces 18a, 19a or 20a, 21a on both sides. This state is the half lock state described above.

図４，５は本発明に係るリクライニング装置の第２の実施の形態を示していて、図４は図１と同じ状態を、図５は図３と同じ状態をそれぞれ示している。そのため、図４，５では、図１，３と共通する部分に同一符合を付してある。 4 and 5 show a second embodiment of the reclining device according to the present invention. FIG. 4 shows the same state as FIG. 1, and FIG. 5 shows the same state as FIG. Therefore, in FIGS. 4 and 5, parts common to those in FIGS.

図４に示すように、ベースブラケット１とアームブラケット２との間には、リクライニング装置３のベース部材４やツース部材５とほぼ同心状に渦巻きばねタイプのリターンばね２７が配置される。このリターンばね２７は、アームブラケット２と連結されるシートバックに前倒れ方向の付勢力を付与するためのものである。 As shown in FIG. 4, a return spring 27 of a spiral spring type is arranged between the base bracket 1 and the arm bracket 2 substantially concentrically with the base member 4 and the tooth member 5 of the reclining device 3. The return spring 27 is for applying a biasing force in the forward tilt direction to the seat back connected to the arm bracket 2.

そして、リターンばね２７の内端部２７ａはベース部材４の係止突起部２８に係止され、外端部２７ｂはアームブラケット２の係止突起部２９に係止される。これにより、ツース部材５やアームブラケット２を含むシートバックには前倒れ方向（車両前方方向）への付勢力Ｆｂが常時付与されている。この付勢力Ｆｂは、リクライニング装置３がロック解除状態にある時に、当該付勢力Ｆｂだけでシートバックを最後傾位置から最前傾位置まで前倒れさせることができるのに十分な大きさに設定されている。 Then, the inner end portion 27a of the return spring 27 is locked to the locking projection portion 28 of the base member 4, and the outer end portion 27b is locked to the locking projection portion 29 of the arm bracket 2. As a result, the seat back including the tooth member 5 and the arm bracket 2 is always provided with the urging force Fb in the forward leaning direction (forward direction of the vehicle). The urging force Fb is set to a magnitude sufficient to cause the seat back to lean forward from the last tilt position to the frontmost tilt position only by the urging force Fb when the reclining device 3 is in the unlocked state. There is.

このように、ツース部材５に付加される車両前方方向への力に着目した場合には、リクライニング装置３の配置形態として、第１のロック部材１１が車両前方方向を指向するように設定する。 In this way, when focusing on the force applied to the tooth member 5 in the vehicle front direction, the reclining device 3 is arranged so that the first lock member 11 is oriented in the vehicle front direction.

図５は図４の要部の拡大した図であって、図３と同じ断面図を示している。すなわち、図５は、図３に示したリクライニング措置３を時計回り方向に９０度回転させて姿勢変更したかたちとなっている。 FIG. 5 is an enlarged view of the main part of FIG. 4 and shows the same sectional view as FIG. That is, FIG. 5 shows a state in which the reclining measure 3 shown in FIG. 3 is rotated 90 degrees in the clockwise direction to change the posture.

そして、同図から明らかなように、リターンばね２７による付勢力Ｆｂの影響を受けて、ベース部材４のアウタフランジ部７とツース部材５のインナフランジ部８との間には芯ずれが生じていて、両者の間の回転隙間αも片寄っている。すなわち、図５に示したベース部材４とツース部材５との関係として、同図の左半部では隙間αがない状態であるのに対して、同図の右半部にのみに回転隙間αが片寄って発生している。 Then, as is clear from the figure, due to the influence of the urging force Fb of the return spring 27, a misalignment occurs between the outer flange portion 7 of the base member 4 and the inner flange portion 8 of the tooth member 5. Therefore, the rotation gap α between the two is also offset. That is, regarding the relationship between the base member 4 and the tooth member 5 shown in FIG. 5, there is no clearance α in the left half of the figure, whereas the rotation clearance α is present only in the right half of the figure. Is generated with a bias.

そして、回転隙間αの片寄りに一致させるべく、第２，第３のロック部材１２，１３のためのそれぞれのガイド面１８ａ，１９ａ，２０ａ，２１ａも、第１〜第３のロック部材１１，１２，１３を１２０度間隔とした場合の位置に対して、片寄り量βだけ第１のロック部材１１側近づくように片寄って形成されている。 The guide surfaces 18a, 19a, 20a, and 21a for the second and third lock members 12 and 13 are also set to the first to third lock members 11 and 11 in order to match the rotation gap α with the offset. It is formed so as to be closer to the first lock member 11 side by the offset amount β with respect to the position where 12 and 13 are spaced by 120 degrees.

したがって、この第２の実施の形態においては、図４に示したリターンばね２７による付勢力Ｆｂに基づく外力が車両前方方向に向かって付加される点を考慮し、図５に示した第１のロック部材１１の向きが上記車両前方方向となるように、リクライニング装置３の姿勢を、図３に示したものに比べて時計回り方向に９０度回転させたものと理解することができる。したがって、この第２の実施の形態においては、外力の作用方向が異なるものの、先の第１の実施の形態と同様の効果が得られることになる。 Therefore, in the second embodiment, considering that the external force based on the biasing force Fb by the return spring 27 shown in FIG. 4 is applied toward the vehicle front direction, the first embodiment shown in FIG. It can be understood that the posture of the reclining device 3 is rotated by 90 degrees in the clockwise direction as compared with that shown in FIG. 3 so that the direction of the lock member 11 is the front direction of the vehicle. Therefore, in the second embodiment, although the action direction of the external force is different, the same effect as the first embodiment can be obtained.

図６は本発明に係るリクライニング装置の第３の実施の形態を示していて、第１の実施の形態である図３の構造にさらなる改良を加えたものである。したがって、図６では図３と共通する部分には同一符合を付してある。 FIG. 6 shows a reclining device according to a third embodiment of the present invention, which is obtained by further improving the structure of FIG. 3 which is the first embodiment. Therefore, in FIG. 6, parts common to those in FIG. 3 are designated by the same reference numerals.

図６に示した第３の実施の形態においては、ベース部材４におけるアウタフランジ部７の内周面のうち第１のロック部材１１に相当する位置、より具体的には、第１のロック部材１１を含みつつ、その第１のロック部材１１をガイドしている両側のガイド部１６，１７にまでまたがるように、円弧状の凹部３０が形成されている。この凹部３０は、アウタフランジ部７の内周面のうち、ベース部材４とツース部材５との間の回転隙間αの片寄りに基づいて実質的にその隙間αががなくなる範囲に形成されている。凹部３０は、両端部の深さが次第に小さくなるように収束していて、縁部３０ａでアウタフランジ部７の内周面に滑らかに連続している。 In the third embodiment shown in FIG. 6, a position corresponding to the first lock member 11 on the inner peripheral surface of the outer flange portion 7 of the base member 4, more specifically, the first lock member. An arcuate concave portion 30 is formed so as to extend over the guide portions 16 and 17 on both sides which guide the first lock member 11 while including 11. The concave portion 30 is formed in the inner peripheral surface of the outer flange portion 7 in a range where the clearance α is substantially eliminated based on the deviation of the rotation clearance α between the base member 4 and the tooth member 5. There is. The recesses 30 are converged so that the depths at both ends gradually become smaller, and are smoothly continuous to the inner peripheral surface of the outer flange portion 7 at the edge 30a.

この第３の実施の形態によれば、ロック機構１０がロック状態であるかロック解除状態であるかにかかわらず、図１に示したようにシートバックの重量Ｆａが下向き（第１のロック部材１１の進退同方向）に作用していて、ベース部材４のアウタフランジ部７に対して片寄っているツース部材５のインナフランジ部８は、ベース部材４のアウタフランジ部７の内周面と凹部３０との境界である両側の縁部３０ａに強く押し当てられ、実質的に二点支持のかたちで支持される。そのため、ベース部材４に対して回転隙間αの範囲内で片寄っているツース部材５の位置を、より安定して維持することができる。 According to the third embodiment, regardless of whether the lock mechanism 10 is in the locked state or the unlocked state, the weight Fa of the seat back is downward (the first lock member) as shown in FIG. The inner flange portion 8 of the tooth member 5, which is biased toward the outer flange portion 7 of the base member 4, acts on the inner peripheral surface of the outer flange portion 7 of the base member 4 and the concave portion. It is strongly pressed against the edge portions 30a on both sides which are boundaries with 30, and is substantially supported by two-point support. Therefore, it is possible to more stably maintain the position of the tooth member 5 that is offset with respect to the base member 4 within the range of the rotation gap α.

また、上記のようにベース部材４に対して縁部３０ａでツース部材５が強く押し当てられて、実質的に二点支持のかたちでツース部材５が支持されているため、シートバックに加わる車両前後方向の負荷に対して十分に対抗することができる。その結果、上記回転隙間αに起因するシートバックの「がたつき」を防止して、シートバックの前後方向での剛性感を一段と高めることができる。 Further, as described above, the tooth member 5 is strongly pressed against the base member 4 at the edge portion 30a, and the tooth member 5 is supported substantially in the form of two-point support. The load in the front-back direction can be sufficiently countered. As a result, it is possible to prevent the rattling of the seat back due to the rotation gap α, and to further enhance the sense of rigidity in the front-back direction of the seat back.

この場合において、ベース部材４側の凹部３０は第１のロック部材１１の両側のガイド部１６，１７にまたがる範囲に形成されているので、例えば乗員の体格等に応じて通常走行時の使用可能範囲でシートバックの傾斜姿勢を変化させたとしても、その程度の姿勢変化であれば、上記の二点支持の状態は安定して維持することが可能である。 In this case, since the recess 30 on the side of the base member 4 is formed in a range that extends over the guide portions 16 and 17 on both sides of the first lock member 11, it can be used during normal traveling depending on, for example, the physique of the occupant. Even if the tilting posture of the seat back is changed within the range, the above-mentioned two-point support state can be stably maintained if the posture changes to that extent.

図７は本発明に係るリクライニング装置の第４の実施の形態を示していて、第１の実施の形態である図３の第１のロック部材１１周りの変形例を示している。したがって、図７では、図３と共通する部分には同一符合を付してある。 FIG. 7 shows a reclining device according to a fourth embodiment of the present invention, and shows a modified example around the first lock member 11 of FIG. 3 which is the first embodiment. Therefore, in FIG. 7, the same parts as those in FIG. 3 are designated by the same reference numerals.

図７では、第１のロック部材４１の形状が図３に示した第１の実施の形態のものと相違していて、同図（ａ）〜（ｃ）の順にその第１のロック部材４１がロック解錠状態からロック状態に至るまでの挙動を示している。図７に示す第１のロック部材４１は、外歯２２の刃先円の曲率半径の中心位置Ｐが、第１のロック部材４１の幅寸法を二分する中心線Ｌ２に対して左右方向に意図的にずらせて設定されている。そのため、同図（ａ）に示すように、第１のロック部材４１が両側のガイド部１６，１７のガイド面１６ａ，１７ａと平行である状態では、外歯２２の一部でのみ内歯９と噛み合うように設定されている。なお、符号Ｌ１はツース部材５の中心線を示している。 In FIG. 7, the shape of the first lock member 41 is different from that of the first embodiment shown in FIG. 3, and the first lock member 41 is in the order of FIGS. Shows the behavior from the unlocked state to the locked state. In the first lock member 41 shown in FIG. 7, the center position P of the radius of curvature of the cutting edge circle of the outer tooth 22 is intentionally leftward and rightward with respect to the center line L2 that bisects the width dimension of the first lock member 41. It is set to shift. Therefore, as shown in FIG. 7A, in a state where the first lock member 41 is parallel to the guide surfaces 16a and 17a of the guide portions 16 and 17 on both sides, only a part of the outer teeth 22 serves as the inner teeth 9. Is set to mesh with. The reference character L1 indicates the center line of the tooth member 5.

したがって、ロック機構１０がロック解除状態からロック状態に移行する際には、図７の（ａ）の状態から同図（Ｂ）の状態に変化したとしても、第１のロック部材４１における外歯２２の一部（時計回り方向に向かって前方側の一部）のみが内歯９と噛み合うことになる。 Therefore, when the lock mechanism 10 shifts from the unlocked state to the locked state, even if the state of FIG. 7A changes to the state of FIG. 7B, the external teeth of the first lock member 41 Only a part of 22 (a part on the front side in the clockwise direction) meshes with the internal teeth 9.

そして、同図（ｂ），（ｃ）に示すように、外歯２２の一部が内歯９と噛み合った後に、第１のロック部材４１が内歯９に向かってなおもカム１４により押し込まれると、第１のロック部材４１の作動面２６が傾斜面であることとも相俟って、両側のガイド面１６ａ，１７ａで挟まれている領域内で第１のロック部材４１がいわゆる転び現象によって傾きを生ずることになる。そのため、最終的には、第１のロック部材４１のうち対角の関係にある二箇所Ｐ１，Ｐ２が両側のガイド面１６ａ，１７ａに当接し、同時に、外歯２２の全面が内歯９と噛み合うことになる。 Then, as shown in (b) and (c) of the figure, after a part of the outer teeth 22 meshes with the inner teeth 9, the first lock member 41 is still pushed toward the inner teeth 9 by the cam 14. Then, coupled with the fact that the operating surface 26 of the first lock member 41 is an inclined surface, the so-called rolling phenomenon of the first lock member 41 in the area sandwiched by the guide surfaces 16a, 17a on both sides is provided. Will cause a tilt. Therefore, finally, two diagonal positions P1 and P2 of the first lock member 41 come into contact with the guide surfaces 16a and 17a on both sides, and at the same time, the entire surface of the outer tooth 22 becomes the inner tooth 9. It will engage.

ここでは、第１のロック部材４１とその両側のガイド面１６ａ，１７ａとを含んでいて、且つ第１のロック部材４１の形状の特殊性に基づいて、ロック状態に移行する過程の末期に、第１のロック部材４１を傾動変位させながら、当該第１のロック部材４１のうち対角の関係にある二箇所Ｐ１，Ｐ２を両側のガイド面１６ａ，１７ａに積極的に押し付ける機構を、第１のロック部材４１の姿勢矯正機構４０と定義する。 Here, based on the peculiarity of the shape of the first lock member 41, which includes the first lock member 41 and the guide surfaces 16a and 17a on both sides thereof, at the final stage of the process of transitioning to the locked state, A mechanism for positively pressing two diagonal points P1 and P2 of the first lock member 41 against the guide surfaces 16a and 17a on both sides while tilting and displacing the first lock member 41 is provided. It is defined as the posture correction mechanism 40 of the lock member 41.

したがって、この第４の実施の形態では、ロック状態において、第１のロック部材４１の外歯２２が内歯９に噛み合うのに加えて、姿勢矯正機構４０によるいわゆる「がた詰め」機能により、第１のロック部材４１の対角上の二箇所Ｐ１，Ｐ２が両側のガイド面１６ａ，１７ａに当接することになる。そのため、ベース部材４とツース部材５との間の回転隙間αに起因する両者間の「がたつき」の発生をより確実に防止して、シートバックの前後方向での剛性感が一段と高いものとなる。 Therefore, in the fourth embodiment, in the locked state, in addition to the outer teeth 22 of the first lock member 41 meshing with the inner teeth 9, the posture correcting mechanism 40 has a so-called “rattle” function. Two diagonal positions P1 and P2 of the first lock member 41 come into contact with the guide surfaces 16a and 17a on both sides. Therefore, the occurrence of “rattle” between the base member 4 and the tooth member 5 due to the rotational gap α between the base member 4 and the tooth member 5 is more reliably prevented, and the rigidity of the seat back in the front-rear direction is much higher. Becomes

また、先に第１の実施の形態として説明した第２，第３のロック部材１２，１３のためのガイド面１９ａ，２０ａが、第１のロック部材４１側に所定量βだけ片寄っていることによる「がた詰め」機能に加えて、上記姿勢矯正機構４０による「がた詰め」機能を併用することで、シートバックの前後方向負荷に対して第１〜第３のロック部材１１，１２，１３がこじれるような変位が生じにくく、これによってもシートバックの前後方向での剛性感がさらに向上する。 Further, the guide surfaces 19a and 20a for the second and third lock members 12 and 13 described above as the first embodiment are deviated to the first lock member 41 side by a predetermined amount β. In addition to the "rattle" function by the above, the "rattle" function by the posture correcting mechanism 40 is used together, so that the first to third lock members 11, 12, against the longitudinal load of the seat back. Displacement such as twisting of 13 is less likely to occur, and this also further improves the rigidity of the seat back in the front-rear direction.

ここで、上記第４の実施の形態では、第１のロック部材４１の姿勢矯正機構４０を、先に説明した第１の実施の形態のものに適用した場合を例にとって説明したが、必要に応じて、上記第１のロック部材４１の姿勢矯正機構４０を、上記第２の実施の形態または第３の実施の形態のものにも適用することが可能である。 Here, in the fourth embodiment, the case where the posture correcting mechanism 40 of the first lock member 41 is applied to the one of the first embodiment described above has been described as an example. Accordingly, the posture correcting mechanism 40 of the first lock member 41 can be applied to that of the second embodiment or the third embodiment.

３…リクライニング装置
４…ベース部材
５…ツース部材
７…アウタフランジ部（軸支持部）
８…インナフランジ部
９…内歯
１０…ロック機構
１１…第１のロック部材
１２…第２のロック部材
１３…第１３のロック部材
１４…カム（カム部材）
１５…ロックばね
１６，１７…ガイド部
１６ａ，１７ａ…ガイド面
１８，１９…ガイド部
１８ａ，１９ａ…ガイド面
２０，２１…ガイド部
２０ａ，２１ａ…ガイド面
２２…外歯
２７…リターンばね
３０…凹部
４０…姿勢矯正機構
４１…第１のロック部材
α…回転隙間
β…片寄り量
γ…摺動隙間 3... Reclining device 4... Base member 5... Tooth member 7... Outer flange part (shaft support part)
8... Inner flange part 9... Inner teeth 10... Lock mechanism 11... First lock member 12... Second lock member 13... Thirteenth lock member 14... Cam (cam member)
15... Lock spring 16, 17... Guide part 16a, 17a... Guide surface 18, 19... Guide part 18a, 19a... Guide surface 20, 21... Guide part 20a, 21a... Guide surface 22... External tooth 27... Return spring 30... Recessed portion 40... Posture correction mechanism 41... First lock member α... Rotational gap β... Offset amount γ... Sliding gap

Claims

A base member arranged on the seat cushion side,
A tooth member that is disposed on the seat back side and is rotatably supported by a shaft supporting portion having the base member side as a shaft hole, and that has a tooth inner shaft and a center of rotation thereof.
Outer portions that are arranged at intervals of about 120 degrees around the rotation center of the tooth member, are guided to be movable in the radial direction by guide portions provided on the base member, and can be meshed with and engaged with the inner teeth. Three lock members having teeth, a cam member that engages and disengages the three lock members with the tooth member by engaging the inner teeth and the outer teeth as engaging portions, and the cam members with the inner teeth. A lock mechanism composed of a lock spring that urges in a lock direction in which the outer teeth mesh with each other, and a lock mechanism,
In a vehicle seat reclining device equipped with
A first lock member of the three lock members is arranged in a direction in which the tooth member is offset within a range of a rotation gap of the shaft support portion by a force acting on the seat back,
Of the three lock members, the guide surface of the guide portion that guides the second and third lock members has an amount that is slightly larger than the sum of the sliding clearance on the guide surface and the rotation clearance. A reclining device for a vehicle seat, wherein the reclining device is formed so as to be displaced in a direction in which the members are offset.

The reclining device for a vehicle seat according to claim 1,
The three lock members are guided movably in the radial direction by a pair of guide surfaces that sandwich the lock member from both sides,
A reclining device for a vehicle seat, wherein each pair of guide surfaces for guiding the second and third lock members is formed so as to be displaced in a direction toward one side of the tooth member.

The reclining device for a vehicle seat according to claim 2,
Between the base member and the tooth member, a return spring that biases the seat back in the forward direction with respect to the seat cushion is provided,
The first lock member is arranged in a direction in which the tooth member is biased by an urging force of the return spring within a range of a rotation gap of the shaft support portion. apparatus.

The reclining device for a vehicle seat according to claim 2,
In the shaft support portion, there is a rotational pair relationship in which the base member side is a shaft hole and the tooth member side is a shaft.
Due to the weight of the seat cushion, the rotation gap is provided on the upper side of the inner peripheral surface of the shaft hole,
The reclining device for a vehicle seat, wherein the first lock member is arranged at a lower position on the side opposite to the maximum position of the rotation gap.

The reclining device for a vehicle seat according to any one of claims 2 to 4,
Each pair of guide surfaces for guiding the second and third lock members is a part of the tooth member with respect to the position of one guide surface when the three lock members are arranged at intervals of about 120 degrees. A reclining device for a vehicle seat, wherein the reclining device is formed so as to be displaced in parallel to a deviation direction.

The reclining device for a vehicle seat according to any one of claims 2 to 5,
The shaft supporting portion is formed in an annular shape by half blanking on the outer peripheral portion of the base member,
While the outer peripheral surface of the circular tooth member is rotatably supported with the inner peripheral surface of the shaft support portion as a shaft hole,
A reclining device for a vehicle seat, characterized in that a recess is formed in an inner peripheral surface of the shaft support portion at a position offset to the tooth member.

The reclining device for a vehicle seat according to any one of claims 2 to 6,
A posture correction mechanism that corrects the posture of the first lock member is provided between the first lock member and a guide surface of the guide portion that guides the first lock member. Vehicle seat reclining device.

The reclining device for a vehicle seat according to claim 7,
The outer teeth of the first lock member are set at a position where the center of the arc of the addendum circle is displaced in the left-right direction with respect to the center line that bisects the first lock member in the width direction,
In a locked state in which the inner teeth and the outer teeth are meshed with each other, the first lock member is inclined with respect to the guide surface, and the first lock member comes into contact with the guide surface at two diagonal positions of the first lock member. A reclining device for a vehicle seat, which is characterized in that it comes into contact with it.