Recliner of vehicle seat

Abstract

A locking device for a vehicle seat. The recliner includes a plate holder including a first catch protrusion on one of a plurality of guide blocks, a sector gear including an internal gear on an inner surface thereof, a plurality of pawl teeth each configured to be moved between a pair of the guide blocks, the pawl teeth including catch hooks on portions of inner surfaces thereof, an operation cam including a second catch protrusion protruding therefrom; and a return spring having a spiral shape, the return spring including a center inner end portion hooked and supported on the second catch protrusion and an outer end portion hooked and supported on the first catch protrusion, wherein a support protrusion protrudes from the operation cam to support the return spring while making point contact with a center inner surface of the return spring.

Claims

1. A recliner for a vehicle seat, the recliner comprising: a plate holder comprising a plurality of guide blocks that are radially arranged with a gap therebetween and protrude in an axial direction, a first catch protrusion being formed on at least one of the guide blocks; a sector gear configured to be rotated relative to the plate holder and comprising an internal gear on an inner surface thereof; a plurality of pawl teeth each configured to be moved between a pair of the guide blocks, the pawl teeth comprising external gears on outer surfaces thereof for engagement with the external gear, and catch hooks on portions of inner surfaces thereof; an operation cam comprising a shaft hole in a center portion thereof, a plurality of pull hooks configured to be connected to the catch hooks so as to pull or push the pawl teeth, and a second catch protrusion protruding therefrom; and a return spring having a spiral shape, the return spring comprising a center inner end portion hooked and supported on the second catch protrusion and an outer end portion hooked and supported on the first catch protrusion, wherein a projection protrudes axially from the operation cam and comprises a support protrusion that protrudes radially from a remainder of the projection to support the return spring while making point contact with a center inner surface of the return spring.

2. The recliner of claim 1, wherein the inner end portion and the outer end portion of the return spring are provided at both sides of the shaft hole of the operation cam, and the support protrusion of the operation cam is provided between the inner end portion and the outer end portion of the return spring.

3. The recliner of claim 2, wherein the support protrusion is located from the outer end portion of the return spring in a direction in which the return spring is wound when the recliner is unlocked.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) These and/or other aspects will become apparent and more readily appreciated from the following description of the disclosed embodiment, taken in conjunction with the accompanying drawings in which:

(2) FIG. 1 is an exploded perspective view illustrating a recliner of the related art;

(3) FIG. 2 is a cross-sectional view illustrating the recliner illustrated in FIG. 1;

(4) FIG. 3 is an exploded perspective view illustrating a recliner according to an aspect of the presently disclosed embodiment;

(5) FIG. 4 is a plan view illustrating an operation cam of the recliner illustrated in FIG. 3; and

(6) FIG. 5 is a cross-sectional view illustrating the recliner illustrated in FIG. 3.

DETAILED DESCRIPTION

(7) Reference will now be made in detail to aspects of the presently disclosed embodiment, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the presently disclosed embodiment may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the aspects are merely described below, by referring to the figures, to explain aspects of the present description. As used herein, the term and/or includes any and all combinations of one or more of the associated listed items. Expressions such as at least one of, when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

(8) Specific aspects of the presently disclosed embodiment will now be described with reference to the accompanying drawings. In the drawings, thicknesses of lines and sizes of elements may be exaggerated for clarity and ease of illustration. In addition, terms used herein are defined in consideration of functions of the presently disclosed embodiment, but the terms may vary according to the intention of users or operators, or customs. Therefore, these terms should be construed based on the entirety of the present disclosure.

(9) FIG. 3 is an exploded perspective view illustrating a recliner according to an aspect of the presently disclosed embodiment, FIG. 4 is a plan view illustrating an operation cam 140 of the recliner illustrated in FIG. 3, and FIG. 5 is a cross-sectional view illustrating the recliner illustrated in FIG. 3.

(10) As illustrated in FIGS. 3 to 5, according to the aspects of the presently disclosed embodiment, the recliner for a vehicle seat includes a plate holder 110, a sector gear 120, pawl teeth 130, the operation cam 140, a return spring 150, and a guide ring 160.

(11) The plate holder 110 is configured to be coupled to one of a seat cushion frame and a seat back frame, and a penetration hole 111 is formed in a center portion of the plate holder 110 such that a lever shaft connected to an operation lever may be inserted through the penetration hole 111.

(12) A plurality of guide blocks 112 are provided on a side (facing the sector gear 120) of the plate holder 110 to guide reciprocation of the pawl teeth 130 (described later) in radial directions of the plate holder 110.

(13) The plurality of guide blocks 112 are arranged on the side of the plate holder 110 in a radial shape with a gap therebetween, protruding from the side of the plate holder 110 toward the sector gear 120. In the aspect of the presently disclosed embodiment, the number of the guide blocks 112 is four as shown in FIG. 2, but may vary with the number of the pawl teeth 130.

(14) A first catch protrusion 113 protrudes from one of the guide blocks 112 to support an outer end portion of the return spring 150 (described later).

(15) A rim portion protrudes from an outer edge side of the sector gear 120, and an internal gear is formed on an inner surface of the rim portion. The sector gear 120 is coupled to the plate holder 110 using the guide ring 160 and forms an installation space together with the plate holder 110 for the pawl teeth 130, the operation cam 140, and the return spring 150 (described later).

(16) A penetration hole is formed through a center portion of the sector gear 120 and communicates with the penetration hole 111 of the plate holder 110 such that the lever shaft may be inserted through the penetration holes and may rotate when the recliner is operated.

(17) Each of the pawl teeth 130 is placed between a pair of adjacent guide blocks 112 and may be reciprocated in radial directions of the plate holder 110 while being guided by the pair of adjacent guide blocks 112.

(18) Two or more pawl teeth 130 are provided, and external gears 131 corresponding to the internal gear 121 are formed on outer surfaces (facing the internal gear 121 of the sector gear 120) of the pawl teeth 130, and catch hooks 132 configured to be pulled by the operation cam 140 toward the operation cam 140 (described later) are formed on inner surfaces (facing the operation cam 140) of the pawl teeth 130.

(19) The catch hooks 132 protrude from portions of inner surfaces of the pawl teeth 130 toward the operation cam 140 and are then bent to form catch slots in a circumferential direction. That is, the catch hooks 132 protrude from portions of inner surfaces of the pawl teeth 130 directly guided by the guide blocks 112.

(20) In the aspect of the presently disclosed embodiment, a plurality of pawl teeth 130 are provided, and a pair of pawl teeth 130 arranged around the operation cam 140 at an angle of 180 from each other is grouped as one set. In detail, two pairs of pawl teeth 130 are provided as shown in FIG. 3, and each pair of pawl teeth 130 arranged at an angle of 180 from each other is grouped as one set.

(21) The operation cam 140 may be rotated by the lever shaft connected to a manipulation lever of the recliner that a passenger manipulates. To this end, a shaft hole 141 is formed through a center portion of the operation cam 140, and the lever shaft may be inserted through the shaft hole 141 and spline coupled to the operation cam 140. A plurality of protrusions are formed on an inner side of the shaft hole 141 to prevent the lever shaft from rotating relative to the shaft hole 141, and grooves having shapes corresponding to the protrusions are longitudinally formed in an outer surface of the lever shaft.

(22) The operation cam 140 is placed on a center portion of the plate holder 110 in a state in which the shaft hole 141 of the operation cam 140 communicates with the penetration hole 111 of the plate holder 110. The operation cam 140 is placed at a center position surrounded by the plurality of pawl teeth 130 to lock or unlock the recliner by pushing or pulling the pawl teeth 130.

(23) Pull hooks 142 protrude from an outer surface of the operation cam 140 toward the catch slots of the catch hooks 132 of the pawl teeth 130 such that the pull hooks 142 may be connected to the catch hooks 132 of the pawl teeth 130 to pull the pawl teeth 130 toward the operation cam 140 or push the pawl teeth 130 toward the internal gear 121 of the sector gear 120. The number of the pull hooks 142 is the same as the number of the pawl teeth 130 such that the pull hooks 142 may correspond to the catch hooks 132 of the pawl teeth 130, and when the operation cam 140 is rotated (when the recliner is locked or unlocked), the pull hooks 142 spontaneously pulls or pushes the pawl teeth 130. Insertion slots are formed in the pull hooks 142 such that the catch hooks 132 may be inserted into the insertion slots.

(24) A second catch protrusion 143 protrudes from a surface (facing the sector gear 120) of the operation cam 140 to support an inner end portion of the return spring 150 (described later). A support projection 144 having a ring shape protrudes from an edge portion of the operation cam 140 around the shaft hole 141 to support an inner side of the return spring 150 (described later).

(25) The return spring 150 has a spiral shape, and the outer end portion and the inner end portion of the return spring 150 are bent so as to be respectively hooked on the first catch protrusion 113 and the second catch protrusion 143.

(26) A portion of the return spring 150 on which the inner end portion is formed is referred to as an inner portion, and the inner portion is supported by the support projection 144 of the operation cam 140, that is, a support protrusion 145 (described later).

(27) Here, as shown in FIG. 5, the inner end portion and the outer end portion of the return spring 150 are provided at both sides of the shaft hole 141 at an angle of greater than 90, preferably about 180.

(28) The support protrusion 145 is provided on the support projection 144 of the operation cam 140, and when the return spring 150 supported by the support projection 144 is wound and applies elastic force during unlocking of the recliner, the support projection 144 does not make surface contact with an inner surface of the return spring 150 but makes point contact with the inner surface of the operation cam 140 owing to the support protrusion 145.

(29) The support protrusion 145 is provided between the inner end portion and the outer end portion of the return spring 150, and when the return spring 150 is wound during unlocking of the recliner, it is preferable that the support protrusion 145 make point contact with an inner surface of the inner portion of the return spring 150 for smooth rotation of the operation cam 140.

(30) In addition, preferably, the support protrusion 145 is formed in a counterclockwise direction (a direction in which the return spring 150 is unwound) from the inner end portion of the return spring 150.

(31) An operation of the recliner for a vehicle seat will now be briefly described according to an aspect of the presently disclosed embodiment.

(32) In general, a vehicle seat is put in a state in which the inclined angle of a seat back is fixed to a certain value. That is, the recliner is usually put in a locked state. That is, the recliner is in a locked state in which the external gears 131 of the pawl teeth 130 are engaged with the internal gear 121 of the sector gear 120 to prevent rotation of the sector gear 120.

(33) In this state, a passenger may manipulate the operation lever of the recliner to adjust the inclination of the seat back. Then, the lever shaft connected to the operation lever of the recliner is rotated a certain angle, and then the operation cam 140 is also rotated a certain angle by the rotation of the lever shaft.

(34) At this time, as the pull hooks 142 of the operation cam 140 are inserted into the catch slots of the catch hooks 132 of the pawl teeth 130, the pull hooks 142 pull the pawl teeth 130.

(35) Then, the external gears 131 of the pawl teeth 130 engaged with the internal gear 121 of the sector gear 120 are separated and disengaged from the internal gear 121 of the sector gear 120, and thus the recliner is unlocked.

(36) According to the presently disclosed embodiment, when the return spring 150 applies elastic force while being wound during unlocking of the recliner, the inner surface of the inner portion of the return spring 150 is in point contact with the support protrusion 145 of the operation cam 140, thereby minimizing friction between the return spring 150 and the operation cam 140 and improving manipulation of the recliner.

(37) While the presently disclosed embodiment has been described with reference to the accompanying drawings according to aspects, these aspects are for illustrative purposes only, and it will be understood by those of ordinary skill in the art that various changes and other equivalent aspects may be made therefrom. Therefore, the scope and spirit of the presently disclosed embodiment should be defined by the following claims.