WO2019022445A1

WO2019022445A1 - Headrest tilting device

Info

Publication number: WO2019022445A1
Application number: PCT/KR2018/008252
Authority: WO
Inventors: Hae Il Jeong
Original assignee: Woobo Tech Co., Ltd.
Priority date: 2017-07-25
Filing date: 2018-07-23
Publication date: 2019-01-31
Also published as: KR101995345B1; KR20190011530A

Abstract

The present invention relates to a headrest tilting device. Particularly, the headrest tilting device includes a bracket, a first locking part connected to the bracket, and a second locking part which is rotatable with respect to the bracket and locked to or unlocked from the first locking part, wherein the first locking part includes a first gear, the second locking part includes a second gear engaged with the first gear, any one of the first and second gears includes a plurality of gear teeth formed thereon, and positions at which a rotation center of the bracket and the second locking part are connected to a stay are spaced apart from each other. Thus, the tilting device can be modularized, can be easily installed at a conventional stay rod, and can have a simple manufacturing process and a simple structure.

Description

HEADREST TILTING DEVICE

This invention relates to a headrest tilting device which tilts a headrest in various angles.

Generally, a vehicle headrest is installed at an upper end of a seat to be axially rotated by a tilting device, and prevents neck damage in the event of rear-end collision by supporting a back of a passenger's head or is also used as a head support by being lifted and rotated according to a height of a head of the passenger.

The conventional headrest tilting device includes a stay rod mounted on a seat and including a pair of vertical bars and a horizontal bar, a fixed gear part having a bottom surface of a curved surface fixed to an upper outer circumferential surface of the horizontal bar and an upper surface of the curved surface fixed perpendicular to the horizontal bar, and including a fixed gear including gear teeth formed at the upper surface thereof, a connecting link having one end hinge-connected to the fixing gear, a rotating gear part partially hinge-coupled to a cross section of the connecting link and including a rotating gear having gear teeth engaged with the gear teeth of the fixed gear and elastically supported by the first spring for axial rotation, a moving bar which has both ends fitted onto the upper end of the connecting link to be movable, is parallel to the horizontal bar, includes a pair of plates fixed to an outer end thereof, and is elastically supported on the horizontal bar by the second spring, and a rotating sphere having one end hinge-connected to the horizontal bar of the stay rod and the other end surrounding an outer circumferential part of the moving bar.

In the conventional headrest tilting device, the fixed gear and the rotating sphere are fixed to the horizontal bar of the stay rod, and thus an installation process is complicated.

Further, the plate, the moving bar, and the rotating sphere are separately provided, which thus exceedingly complicates a structure of the device.

[Prior-Art Documents]

[Patent Documents]

(Patent Document 1) Korean Patent Laid-Open Publication No. 10-0577413

The present invention is contrived to solve the foregoing problem, an objective of the present invention is to provide a headrest tilting device which is easy to install and has a simple structure.

In order to accomplish the foregoing objective, a headrest tilting device includes a bracket, a first locking part connected to the bracket, and a second locking part locked to or unlocked from the first locking part, wherein the bracket is rotatable with respect to the second locking part, the first locking part includes a first gear, the second locking part includes a second gear engaged with the first gear, at least one of the first and second gears includes a plurality of gear teeth, and positions at which a rotation center of the bracket and the second locking part are connected to a stay are spaced apart from each other.

The bracket may include a first bracket plate and second and third bracket plates formed to be bent from both sides of the first bracket plate, and the first and second gears may be disposed in the bracket, wherein the second locking part may include a first locking plate and second and third locking plates formed to be bent from both sides of the first locking plate, the stay may be installed at the first locking plate, the bracket may be rotatably installed on the second locking part by a second locking part-shaft, the second locking part may be rotatably installed on the bracket by the second locking-part shaft, the second locking part-shaft may be installed at the second and third locking plates, a return spring may be installed on the second locking-part shaft, the return spring may be configured to rotate the bracket with respect to the second locking part when the first and second locking parts are unlocked, the second gear may be formed on the second locking plate, and the second gear may include a plurality of gear teeth formed thereon.

The first locking part may include a first locking protrusion and a second locking protrusion spaced apart from the first locking protrusion in a front-rear direction, the second locking plate may include a locking injecting part by which the first and second locking protrusions are locked, the first locking part may further include a first locking part-spring configured to apply an elastic force thereto, a vertical length of the third locking plate may be formed to be shorter than a vertical length of the second locking plate, one end of the return spring may be locked on the second locking plate, the other end of the return spring may be locked on the third bracket plate, the first locking part may be rotatably installed on the bracket by the first locking part-shaft, and the first locking part-shaft may be installed in the second bracket plate and the third bracket plate.

The second locking part may be installed under the first rod disposed in a lateral direction of the stay rod.

The second locking part may include a stopper-protruding part, by which the first bracket plate is locked, protruding forward or rearward, and one end of the first bracket plate may be spaced apart from the first locking plate to form a space between the first bracket plate and the first locking plate, wherein the stopper-protruding part may be disposed in the space.

A headrest tilting device according to the present invention has the following effects.

The headrest tilting device includes a bracket, a first locking part connected to the bracket, and a second locking part locked to or unlocked from the first locking part, wherein the bracket is rotatable with respect to the second locking part, the first locking part includes a first gear, the second locking part includes a second gear engaged with the first gear, any one of the first and second gears includes a plurality of gear teeth formed thereon, and positions at which a rotation center of the bracket and the second locking part are connected to the stay are spaced apart from each other. Thus, the tilting device can be modularized, can be easily installed at a conventional stay rod, and can have a simplified manufacturing process and a simple structure.

The bracket includes a first bracket plate and second and third bracket plates formed to be bent from both sides of the first bracket plate, the first and second gears are disposed in the bracket, the second locking part includes a first locking plate and second and third locking plates formed to be bent from both sides of the first locking plate, the stay is installed at the first locking plate, the bracket is rotatably installed on the second locking part by a second locking part-shaft, the second locking part-shaft is installed in the second locking plate and the third locking plate, a return spring is installed on the second locking-part shaft, the return spring is configured to rotate the bracket with respect to the second locking part when the first and second locking parts are unlocked, the second gear is formed on the second locking plate, and the second gear includes a plurality of gear teeth formed thereon, and thus, a structure of the device can be simplified, and the durability of the device can be strengthened.

The first locking part includes a first locking protrusion and a second locking protrusion spaced apart from the first locking protrusion in a front-rear direction, the second locking plate includes a locking injecting part by which the first and second locking protrusions are locked, the first locking part further includes a first locking part-spring configured to apply an elastic force thereto, a vertical length of the third locking plate is formed to be shorter than a vertical length of the second locking plate, one end of the return spring is locked on the second locking plate, the other end of the return spring is locked on the third bracket plate, the first locking part is rotatably installed on the bracket by the first locking part-shaft, and the first locking part-shaft is installed in the second bracket plate and the third bracket plate, and thus the device can be operated without a separate button or wire, and a structure of the device can be remarkably simplified.

The first locking part is installed under the first rod, and, when the headrest is tilted, a lower portion of the headrest protrudes forward from an upper portion of the headrest, and thus a curved head can be more stably supported.

The second locking part includes a stopper-protruding part by which the first bracket plate is locked and which protrudes forward or rearward, one end of the first bracket plate is spaced apart from the first locking plate to form a space between the first bracket plate and the first locking plate, and the stopper-protruding part is disposed in the space, and thus, since punching is not performed to form a space into which the stopper-protruding part is inserted, a manufacturing process can be more simplified.

FIG. 1 is a perspective view of a headrest tilting device according to one embodiment of the present invention.

FIG. 2 is an exploded rear perspective view of the headrest tilting device according to one embodiment of the present invention.

FIG. 3 is a rear view of the headrest tilting device according to one embodiment of the present invention.

FIG. 4 is a cross-sectional view of the headrest tilting device according to one embodiment of the present invention (an initial state).

FIG. 5 is a cross-sectional view of the headrest tilting device according to one embodiment of the present (a first tilted state).

FIG. 6 is a cross-sectional view of the headrest tilting device according to one embodiment of the present invention (a released state).

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

For reference, components of the present invention which are the same as those in the related art will be described below with reference to the above-described related art, and the detailed description thereof will be omitted.

When it is described that any part is positioned "on" another part, it means that the part is directly on another part or above another part with at least one intervening part. In contrast, when any part is described to be positioned "directly on" another part, it means that there is no intervening part between the two parts.

Technical terms used herein are for only describing specific embodiments and are not intended to limit the present invention. Singular forms used herein include plural forms unless explicitly described to the contrary. A meaning of "comprising" used in the specification embodies specific characteristics, areas, integers, steps, operations, elements, and/or components, and does not exclude the presence or addition of other characteristics, areas, integers, steps, operations, elements, and/or components.

Terms representing a relative space such as "lower," "upper," and the like may be used for more easily describing a relationship between one part and another part shown in the drawings. Such terms are intended to include other meanings or operations of an apparatus used together with a meaning that is intended in the drawings. For example, when an apparatus is inverted in the drawings, any part described as disposed at a "lower" part below another part is described as being disposed at an "upper" part above another part. Therefore, the illustrative term "lower" includes both upward and downward directions. An apparatus may be rotated by 90° or another angle, and the terms representing the relative space are accordingly analyzed.

When it is described that any element is "connected" to another element, it should be understood that the element is directly connected to another element or still another element may be interposed therebetween.

As illustrated in FIGS. 1 to 6, a headrest tilting device in an embodiment of the present invention includes a bracket 110 including a first bracket plate 111, and a second bracket plate 112 and a third bracket plate 113 formed to be bent from both sides of the first bracket plate 111, a first locking part 120 including a first gear 121 formed thereon and connected to the bracket 110, and a second locking part 130 including a second gear 134 engaged with the first gear 121 and locked to or unlocked from the first locking part 120. The bracket 110 is rotatable with respect to the second locking part 130, and the first and

second gears

121 and 134 are disposed in the bracket 110. The second locking part 130 includes a first locking plate 131, a second locking plate 132 and a third locking plate 133 formed to be bent from both sides of the first locking plate 131. A first rod 11 of a stay 10 is installed on the first locking plate 131, the bracket 110 is rotatably installed on the second locking part 130 by a second locking part-shaft 160, the second locking part-shaft 160 is installed in the second locking plate 132 and the third locking plate 133, a return spring 150 is installed on the second locking part-shaft 160, the return spring 150 allows the bracket 110 to rotate with respect to the second locking part 130 when the first locking part 120 and the second locking part 130 are unlocked. The second gear 134 is formed at the second locking plate 132, and a plurality of gear teeth are formed at the second gear 134, and positions at which a center of the second locking part-shaft 160 and the second locking part 130 are connected to the stay 10 are spaced apart from each other.

Hereinafter, a width direction of a vehicle is referred to as a lateral direction, a longitudinal direction of the vehicle is referred to as a front-rear direction, and a vertical direction of the vehicle is referred to as a vertical direction.

One of the bracket 110 and the stay 10 is connected to a headrest, and the other one is connected to a backrest.

As illustrated in FIGS. 1 and 2, the stay 10 includes the first rod 11 horizontally disposed in a lateral direction and second rods 12 vertically disposed at both lower portions of the first rod 11. The first rod 11 is disposed in front of the second rod 12. Both sides of the first rod 11 are connected to the second rod 12 by connecting rods disposed in a front-rear direction. The connecting rod is formed to be inclined so that a height thereof decreases forward. Thus, a height of an upper end of the first rod 11 is less than a height of an upper end of the second rod 12. In the embodiment of the present invention, the first rod 11, the connecting rods, and the second rods 12 are integrally formed.

In the embodiment of the present invention, the bracket 110 is connected to the headrest.

The bracket 110 is disposed in the headrest.

The bracket 110 is disposed under the middle of the first rod 11. That is, the bracket 110 is disposed between the second rods 12.

The bracket 110 includes the first bracket plate 111 and the second bracket plate 112 and the third bracket plate 113 formed to be bent rearward from both sides of the first bracket plate 111.

The first bracket plate 111 is formed in a vertically long rectangular shape.

A cut-out part 111a is formed to be vertically long at a lower left portion of the first bracket plate 111. The cut-out part 111a is formed to pass through the first bracket plate 111 in a front-rear direction.

The first bracket plate 111 is disposed at a front side of the device, and the second and

third bracket plates

112 and 113 are disposed at both sides of the device.

Fastening parts 115 are formed to protrude outward (leftward or rightward) from rear ends of the second bracket plate 112 and the third bracket plate 113. The fastening parts 115 are formed by partially bending lower portions of the second bracket plate 112 and the third bracket plate 113 outward. The fastening parts 115 are disposed at lower portions of the third bracket plate 113 and the second bracket plate 112. Thus, upper ends of the fastening part 115 are spaced apart from upper ends of the second bracket plate 112 and the third bracket plate 113. A fastening hole into which a fastening member, such as a bolt, may be fastened is formed on the fastening part 115. The fastening part 115 may allow the bracket 110 to be easily installed on a frame of the headrest.

The first bracket plate 111, the second bracket plate 112, the third bracket plate 113, and the fastening part 115 are integrally formed, and the number of components decreases, and thus a manufacturing process is more simplified, and costs can be effectively reduced.

Second locking part-shaft-through holes are formed in upper portions of the second bracket plate 112 and the third bracket plate 113 to laterally pass through the second bracket plate 112 and the third bracket plate 113.

First locking part-shaft-through holes are formed in lower portions of the second bracket plate 112 and the third bracket plate 113 to laterally pass through the second bracket plate 112 and the third bracket plate 113. The first locking part-shaft-through holes are formed in front of the second locking part-shaft-through holes.

Vertical lengths of the second bracket plate 112 of the third bracket plate 113 are longer than vertical lengths of the first bracket plate 111. Upper ends of the second and

third bracket plates

112 and 113 are spaced apart from an upper end of the first bracket plate 111. The upper ends of the second and

third bracket plates

112 and 113 are formed higher than the upper end of the first bracket plate 111. The center of the second locking part-shaft-through hole is formed at the same height as or a similar height to an upper end of the first bracket plate 111 or formed higher than the upper end of the first bracket plate 111.

The second bracket plate 112 includes a first spring inserting hole formed between the first locking part-shaft-through hole and the second locking part-shaft-through hole. The first spring inserting hole is formed to laterally pass through the second bracket plate 112. The first spring inserting hole is formed behind the center of the second locking part-shaft-through hole. The first spring inserting hole is more adjacent to the first locking part-shaft-through hole than the second locking part-shaft-through hole.

The third bracket plate 113 includes a second spring inserting hole 113a formed between the first locking part-shaft-through hole and the second locking part-shaft-through hole. The second spring inserting hole 113a is formed to laterally pass through the third bracket plate 113. The second spring inserting hole 113a is formed behind the center of the second locking part-shaft-through hole. The second spring inserting hole 113a is more adjacent to the first locking part-shaft-through hole than the second locking part-shaft-through hole. The second spring inserting hole 113a is formed above the first spring inserting hole.

As illustrated in FIG. 2, protruding parts are formed on inner surfaces of the second bracket plate 112 and the third bracket plate 113 to surround the second locking part-shaft-through holes. The protruding parts are formed to be recessed inward from the outside. Therefore, seating grooves are formed at outer sides of the second bracket plate 112 and the third bracket plate 113 to be connected with the second locking part-shaft-through hole.

As illustrated in FIG. 3, the first locking part 120 is connected to the bracket 110.

The first locking part 120 is rotatably installed in the bracket 110 by a first locking part-shaft 125. Thus, the first locking part 120 is rotatable with respect to the bracket 110. Both sides of the first locking part-shaft 125 are formed at the second bracket plate 112 and the third bracket plate 113.

The first locking part 120 is formed in a plate shape and disposed in a front-rear direction.

The first locking part 120 includes a first through hole formed in a lateral direction so that the first locking part-shaft 125 is inserted thereinto.

The first locking part 120 includes the protruding part formed at a surface facing the second bracket plate 112. The protruding part is formed to surround the first through hole. The protruding part may minimize friction between the second bracket plate 112 and the first locking part 120.

A first stepped part having an outer diameter smaller than that of an adjacent part and a second stepped part having an outer diameter smaller than that of the first stepped part are formed at a side opposite of a head part of the first locking part-shaft 125. The first stepped part is inserted into the first locking part 120, and the second stepped part is inserted into the second bracket plate 112. Thus, the first locking part 120 is prevented from moving in a lateral direction.

A head part and a stepped part are formed at a shaft included in the headrest tilting device of the embodiment of the present invention like the first locking part-shaft 125. Further, when a rotating member faces a surface, a protruding part is formed at the rotating member or the facing surface so as to minimize friction.

As illustrated in FIG. 2, the first gear 121 is formed to protrude upward from an upper portion of the first locking part 120. The first gear 121 is formed so that a front-rear width becomes narrower as moved upward.

The first gear 121 is disposed at an upper rear side of the first through hole.

A first locking protrusion 128 and a second locking protrusion 129 spaced apart from the first locking protrusion 128 in a front-rear direction are formed at an upper portion of the first locking part 120. The first locking protrusion 128 and the second locking protrusion 129 protrude upward.

A height of an upper end of the first locking protrusion 128 is less than a height of an upper end of the first gear 121.

The first locking protrusion 128 is continuously formed at the first gear 121 and disposed at an upper rear side of the first through hole.

The second locking protrusion 129 is disposed in front of the first locking protrusion 128 and the first gear 121.

The second locking protrusion 129 is disposed in front of the center of the first through hole.

A height of an upper end of the second locking protrusion 129 is less than a height of an upper end of the first locking protrusion 128 but is less than a height of an upper end of the first gear 121.

The second locking protrusion 129 is inserted into the cut-out part 111a.

A spring locking part 123 at which one end of a first locking part-spring 124 is locked is formed at the first locking part 120. The spring locking part 123 is formed in a lateral direction to pass through the first locking part 120. The spring locking part 123 is disposed under the first gear 121 and the first locking protrusion 128 is disposed at an upper rear side of the center of the first through hole.

The first locking part-spring 124 applies an elastic force to the first locking part 120.

The other end of the first locking part-spring 124 is inserted into the first spring inserting hole of the second bracket plate 112.

The first locking part-spring 124 is provided as an open ring-shaped linear spring as in the conventional invention. The first locking part-spring 124 has a circular arc-shaped central portion, and both end portions thereof are bent in left and right directions.

The bracket 110 is rotatable with respect to the second locking part 130. Therefore, the second locking part 130 is rotatable with respect to the bracket 110.

The second locking part 130 is locked to or unlocked from the first locking part 120.

The second locking part 130 includes the first locking plate 131 horizontally disposed and the second locking plate 132 and the third locking plate 133 formed to be bent downward from both sides of the first locking plate 131. The first, second and

third locking plates

131, 132 and 133 are integrally formed. The second locking part 130 is formed, and thus the strength of the second locking part 130 is increased.

The first locking plate 131 is installed at a lower portion of the first rod 11 through welding. That is, the first locking plate 131 is installed at an outer circumferential surface of the first rod 11.

The first locking plate 131 and the first bracket plate 111 are disposed at the right angle, and the second locking part 130 is disposed between the second bracket plate 112 and the third bracket plate 113. The first bracket plate 111 is disposed in front of the device, and the first locking plate 131 is disposed above the device. Therefore, the device is compact, and each component of the device is disposed between the bracket 110 and the second locking part 130, and thus the device is protected.

The second locking part 130 is disposed above the first locking part 120.

The bracket 110 is rotatably installed at the second locking part 130 by the second locking part-shaft 160. That is, a central axis of the second locking part-shaft 160 is provided as a rotation center of the bracket 110. Both sides of the second locking part-shaft 160 are inserted into the second locking part-shaft-through holes of the second and

third bracket plates

112 and 113 and installed on the second bracket plate 112 and the third bracket plate 113.

The second through holes into which the second locking part-shaft 160 is inserted are formed at the second locking plate 132 and the third locking plate 133 in a lateral direction. Therefore, the second locking part-shaft 160 is installed at the second locking plate 132 and the third locking plate 133.

The second locking part-shaft 160 is disposed to pass through the third bracket plate 113, the third locking plate 133, the second locking plate 132, and the second bracket plate 112 in a lateral direction.

A head part formed at an end of the second locking part-shaft 160 is seated on the seating groove formed at the third bracket plate 113.

The second locking part 130 is in contact with the protruding parts formed at the second bracket plate 112 and the third bracket plate 113 so as to minimize friction.

A first stepped part having a diameter smaller than that of an adjacent part is formed at the side opposite of the head part of the second locking part-shaft 160. The first stepped part is inserted into the second bracket plate 112.

The second gear 134 engaged with the first gear 121 is formed at a lower end of the second locking plate 132 of the second locking part 130. The second gear 134 is disposed in the bracket 110.

As illustrated in FIG. 4, a plurality of gear teeth are formed at the second gear 134. Therefore, the headrest may be tilted in various angles. The gear teeth allow the headrest to move forward and are formed to prevent the headrest from moving rearward. The gear teeth of the second gear 134 are disposed at a front side and a rear side of the center of the second locking part-shaft 160. The gear teeth are formed so that a height of a tooth root of the gear teeth decreases toward the center of the second locking part-shaft 160. Therefore, the headrest can be easily tilted.

A locking injecting part 135 by which the first and second locking

protrusions

128 and 129 are locked is formed at a lower end of the second locking plate 132.

The locking injecting part 135 is formed to protrude downward. The locking injecting part 135 is disposed in front of the second gear 134. The locking injecting part 135 is disposed at a front side of the second locking plate 132.

A return spring locking part 139 is formed to pass through the second locking plate 132 in a lateral direction. The return spring locking part 139 is formed so that a rear side thereof is open. The return spring locking part 139 is formed at a rear end of the second locking plate 132 and is disposed under the center of the second through hole. The return spring locking part 139 is disposed between the second through hole and the second gear 134.

As illustrated in FIG. 3, a vertical length of the third locking plate 133 is formed to be shorter than that of the second locking plate 132. A lower end of the third locking plate 133 is disposed higher than a lower end of the second locking plate 132. That is, the lower end of the third locking plate 133 is spaced apart from the lower end the second locking plate 132.

As illustrated in FIG. 1, a stopper-protruding part 137 by which the first bracket plate 111 is locked is formed to protrude forward or rearward from the second locking part 130. The stopper-protruding part 137 is disposed above the first bracket plate 111. In the embodiment of the present invention, the stopper-protruding part 137 is formed to protrude forward from an upper front portion of the second locking part 130. The stopper-protruding part 137 is formed by upper portions of the second and

third locking plates

132 and 133 and the first locking plate 131 protruding forward from lower portions of the second and

third locking plates

132 and 133. That is, a rear end of the stopper-protruding part 137 is continuously formed from a front end of the first locking plate 131 and front ends of the second and

third locking plates

132 and 133. Therefore, the stopper-protruding part 137 is formed in a "∩" shape. Thus, the durability of the second locking part 130 is strengthened. A lower end of the stopper-protruding part 137 is disposed above the center of the second through hole. Edges between the lower end of the stopper-protruding part 137 and the front ends of the second and

third locking plates

132 and 133 are rounded.

One end (an upper end) of the first bracket plate 111 is vertically spaced apart from the first locking plate 131. Therefore, a gap is formed between the first bracket plate 111 and the first locking plate 131, and the stopper-protruding part 137 is disposed in the gap. The gap prevents the stopper-protruding part 137 and the first bracket plate 111 from interfering with each other when the headrest is tilted.

When a user moves the headrest to an unlocked position, the first bracket plate 111 is locked by the stopper-protruding part 137.

The return spring 150 returning the headrest is installed at the second locking part-shaft 160. The return spring 150 moves the bracket 110 rearward from the second locking part 130.

The return spring 150 is provided as a coil spring.

The second locking part-shaft 160 is inserted into the center portion (a coil part) of the return spring 150, and the return spring 150 is disposed between the second locking plate 132 and the third locking plate 133. One end of the return spring 150 is locked by the return spring locking part 139 of the second locking part 130, and the other end thereof is inserted into the first spring inserting hole of the third bracket plate 113 and locked by the third bracket plate 113. The third locking plate 133 is formed to be short so that the other end of the return spring 150 does not interfere with the third locking plate 133.

The first rod 11 of the stay 10 is installed in the middle (between the front end and the rear end) of the first locking plate 131 in a lateral direction. Specifically, the stay 10 is installed on an upper surface of the first locking plate 131. Thus, the stay 10 is directly installed to the second locking part 130 and connected to the second locking part 130.

Therefore, the first rod 11 of the stay 10 is installed on an outer side of the second locking part 130. Further, the first rod 11 is installed on a surface laterally disposed on the second locking part 130 so as to be stably installed due to an increased contact area.

The headrest tilting device is installed in the center of the first rod 11 of the stay 10 in a concentrated manner.

The backrest is installed at lower portions of the second rods 12 of the stay 10.

Further, positions at which the center of the second locking part-shaft 160 and the stay 10 are connected to the second locking part 130 are spaced apart from each other. That is, a rotation center of the bracket 110 is not disposed to be coaxial with the first rod 11 of the stay 10. The center of the second locking part-shaft 160 is not coaxial with a central axis of the first rod 11.

The positions at which the center of the second locking part-shaft 160 and the stay 10 are connected to the second locking part 130 are spaced apart from each other in a front-rear direction and a vertical direction.

In the embodiment of the present invention, the first rod 11 is disposed at an upper front side of the center of the second locking part-shaft 160.

Hereinafter, operation of the embodiments having the above-described configurations will be described.

As illustrated in FIG. 4, the first gear 121 is engaged with the second gear 134, and the headrest remains upright on the backrest. Thus, when the first gear 121 is engaged with the second gear 134, the first locking part-spring 124 applies an elastic force to the first locking part 120, and thus the first gear 121 adheres to the second gear 134.

As illustrated in FIG. 5, when a user pulls the headrest forward, the first gear 121 is engaged with the next gear teeth of the second gear 134, and the headrest remains tilted forward. When the headrest is tilted, a lower portion of the headrest is disposed in front of an upper portion of the headrest.

As illustrated in FIG. 6, when a user pulls the headrest until the first bracket plate 111 is locked by the stopper-protruding part 137, the first locking protrusion 128 is locked by the locking injecting part 135, and the first locking part 120 rotates about the first locking part-shaft 125 in a clockwise direction. Therefore, the first gear 121 escapes from the second gear 134. Therefore, when the first gear 121 escapes from the second gear 134, the first locking part-spring 124 applies an elastic force to the first locking part 120, and thus the first gear 121 is maintained in a state of being detached from the second gear 134. When the first gear 121 is finally detached from the second gear 134, a front lower portion of the first locking part 120 is locked on an inner surface of the first bracket plate 111.

When the user removes a pulling force, the headrest is moved rearward by an elastic force of the return spring 150. When the headrest is moved to the rearmost side, the second locking protrusion 129 is locked by the locking injecting part 135, and thus the first locking part 120 rotates in a counterclockwise direction. Therefore, the first gear 121 is engaged with the second gear 134 to be locked.

While the present invention has been described with reference to the exemplary embodiments, it may be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the present invention as defined by the appended claims.

[Description of symbols]

[Description of Symbols for Main Parts in Drawings]

10: STAY, 11: HORIZONTAL ROD

12: VERTICAL ROD, 110: BRACKET

111: FIRST BRACKET PLATE, 111a: CUT-OUT PART

112: SECOND BRACKET PLATE, 113: THIRD BRACKET PLATE

113a: SECOND SPRING INSERTING HOLE

115: FASTENING PART

120: FIRST LOCKING PART, 121: FIRST GEAR

123: SPRING LOCKING PART

124: FIRST LOCKING PART-SPRING

125: FIRST LOCKING PART-SHAFT

128: FIRST LOCKING PROTRUSION

129: SECOND LOCKING PROTRUSION

130: SECOND LOCKING PART, 131: FIRST LOCKING PLATE

132: SECOND LOCKING PLATE, 133: THIRD LOCKING PLATE

134: SECOND GEAR, 135: LOCKING INJECTING PART

137: STOPPER-PROTRUDING PART

139: RETURN SPRING LOCKING PART

150: RETURN SPRING, 160: SECOND LOCKING PART-SHAFT

Claims

A headrest tilting device comprising:

a bracket;

a first locking part connected to the bracket; and

a second locking part locked to or unlocked from the first locking part,

wherein the bracket is rotatable with respect to the second locking part,

the first locking part includes a first gear,

the second locking part includes a second gear engaged with the first gear,

at least one of the first and second gears includes a plurality of gear teeth, and

positions at which a rotation center of the bracket and the second locking part are connected to a stay are spaced apart from each other.
The headrest tilting device of claim 1, wherein:

the bracket includes a first bracket plate, and a second bracket plate and a third bracket plate formed to be bent from both sides of the first bracket plate; and

the first and second gears are disposed in the bracket,

wherein the second locking part includes a first locking plate, and a second locking plate and a third locking plate formed to be bent from both sides of the first locking plate,

the stay is installed at the first locking plate,

the bracket is rotatably installed on the second locking part by a second locking part-shaft,

the second locking part is rotatably installed on the bracket by the second locking-part shaft,

the second locking part-shaft is installed at the first and third locking plates,

a return spring is installed on the second locking-part shaft,

the return spring is configured to rotate the bracket with respect to the second locking part when the first and second locking parts are unlocked,

the second gear is formed on the second locking plate, and

the second gear includes a plurality of gear teeth formed thereon.
The headrest tilting device of claim 2, wherein:

the first locking part includes a first locking protrusion and a second locking protrusion spaced apart from the first locking protrusion in a front-rear direction;

the second locking plate includes a locking injecting part by which the first and second locking protrusions are locked;

the first locking part further includes a first locking part-spring configured to apply an elastic force thereto;

a vertical length of the third locking plate is formed to be shorter than a vertical length of the second locking plate;

one end of the return spring is locked on the second locking plate;

the other end of the return spring is locked on the third bracket plate;

the first locking part is rotatably installed on the bracket by the first locking part-shaft; and

the first locking part-shaft is installed in the second bracket plate and the third bracket plate.
The headrest tilting device of claim 1 or 2, wherein the second locking part is installed under the first rod disposed in a lateral direction of the stay rod.
The headrest tilting device of claim 2, wherein:

the second locking part includes a stopper-protruding part, by which the first bracket plate is locked, protruding forward or rearward; and

one end of the first bracket plate is spaced apart from the first locking plate to form a space between the first bracket plate and the first locking plate,

wherein the stopper protruding part is disposed in the space.