Link locking device of seat for vehicle

A link locking device of a vehicle seat is configured to prevent a force exerted on a seat belt from causing the rotation of a height link through a buckle. The device includes a sector gear unit rotatably fastened to a cushion frame and fastened to a link connection unit, to which a height link provided in a seat rail is rotatably coupled, to rotate together and a locking unit rotatably coupled to the cushion frame and fastened to a buckle of a seat belt to engage the sector gear unit and block the rotation of the link connection unit when the buckle is pulled. In this configuration, when the buckle is pulled, the locking unit engages the sector gear unit to restrain the link connection unit from rotating to prevent the rotation of the height link, thereby having the effect of preventing the distortion of the seat cushion.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No. 10-2023-0153754, filed Nov. 8, 2023, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a link locking device of a vehicle seat, and more particularly to a link locking device of a vehicle seat configured to prevent the force exerted on a seat belt from causing a height link to rotate through a buckle.

Description of the Related Art

In general, vehicle seats are equipped with various convenience features for the comfort of passengers.

The convenience features include a sliding function that allows forward and backward adjustment of a seat cushion according to the passenger's body shape, a reclining function that allows tilt adjustment of a seatback corresponding to the backrest, and a seat height adjustment function that allows height adjustment of the seat cushion to fit the passenger's body size.

In addition, the seats are equipped with seat belts for passenger safety, and a buckle for fastening the seat belt is affixed to the upper rail at the top by a separate connecting member and connecting bracket on one side of the seat.

In such a conventional structure, it is possible to support the seat belt even under strong collision loads as long as the separation strength between the upper rail and the lower rail affixed to the vehicle body was sufficient. However, since the buckle for affixing the seat belt is mounted on the rail affixed to the vehicle body, the buckle protrudes excessively when the cushion is adjusted to the lowest position while the buckle is concealed under the cushion when the cushion is adjusted to the highest position.

To address this issue, the buckle was mounted on the seat base rather than the upper rail as in the conventional design so that the buckle could remain in the same position when the base moves according to the height adjustment.

However, when a vehicle equipped with a buckle affixed to the seat base through a connecting bracket is involved in a collision, the force propelling the passenger forward is exerted on the seat belt, the force exerted on the seat belt is transmitted to the buckle, a strong rotational force is transmitted to the height link as the side frame coupled to the buckle is lifted by the force pulling the buckle, and consequently, the buckle side link without a rotation prevention device of the link rotates under the intense load to distort the seat cushion. As a result, the support member in the cushion is damaged, and the support necessary for preventing forward movement and sagging of the cushion is compromised.

Therefore, there is a need to develop a device that restrains the rotation of the link to prevent the impact load of the buckle from causing the buckle side height link to rotate when a strong impact load is applied due to a collision.

DOCUMENT OF RELATED ART

SUMMARY OF THE INVENTION

The present invention is designed to address the issue described above, and an object of the present invention is to provide a link locking device of a vehicle seat configured to prevent the force exerted on a seat belt from causing a height link to rotate through a buckle.

To achieve the object described above, a link locking device of a vehicle seat according to a preferred embodiment of the present invention includes a sector gear unit rotatably fastened to a cushion frame and fastened to a link connection unit, to which a height link provided in a seat rail is rotatably coupled, to rotate together and a locking unit rotatably coupled to the cushion frame and fastened to a buckle of a seat belt to engage the sector gear unit and block the rotation of the link connection unit when the buckle is pulled.

Here, the sector gear unit may include a sector gear unit main body fastened to the link connection unit between the cushion frame and the height link and a sector gear formed from the sector gear unit main body toward the locking unit.

The locking unit may include a base frame fastened to the cushion frame, a rotating member rotatably fastened to the base frame and having a pawl gear to engage the sector gear unit, a guide link rotatably fastened to the base frame and having one side fastened to the buckle to receive the rotational power, and a power transmission unit rotatably positioned on the base frame and having one end fastened to the rotating member and the other end fastened to the guide link to transmit the rotational power of the guide link to the rotating member.

Here, the power transmission unit may include a power transmission unit body bent into a streamlined shape and positioned in tight contact with the guide unit provided concentrically with the rotation axis of the rotating member, a first support portion bent toward the rotation axis at one end of the power transmission unit body to catch on and be supported by a catch groove formed in the guide link, and a second support portion bent toward the sector gear unit at the other end of the power transmission unit body to catch on and be supported by a catch boss formed in the rotating member.

The locking unit may include a buckle shaft positioned through slot holes formed in the base frame and the cushion frame and having one end fastened to the buckle and the other end rotatably fastened to one side of the guide link.

In addition, the locking unit may include an elastic member having one end fastened to the buckle shaft and the other end fasted to the base frame to apply an elastic force to cause the guide link rotated by the buckle to return to its original position.

The base frame may include a rotating member hinge portion to which the rotating member is rotatably fastened and which has an end to which the other end of the elastic member is fastened, and a guide link hinge portion to which the guide link is rotatably fastened.

DETAILED DESCRIPTION OF THE INVENTION

The present invention may be diversely modified and may have various embodiments. Certain embodiments will be illustrated in drawings and specifically described in the detailed description below. It is to be understood that the specific embodiments are not intended to limit the present invention thereto and that all modifications, equivalents, or substitutes within the spirit and technical scope of the present invention are included.

The terms used in the present application are used to describe the specific embodiments only and are not intended to limit the present invention. Singular expressions may include plural expressions unless the context expressly means otherwise.

Unless otherwise defined, all terms used herein, including technological or scientific terms, may have the same meaning as the terms commonly understood by those skilled in the art to which the present invention pertains. Terms defined in commonly used dictionaries may be interpreted as having meanings consistent with the contextual meanings of the related technology and may not be interpreted in an idealistic or overly formal sense unless expressly defined in the present specification.

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

FIGS.1and2are a perspective view and an exploded perspective view schematically illustrating a link locking device of a vehicle seat installed in a seat according to an embodiment of the present invention;FIGS.3and4are a perspective view and an exploded perspective view schematically illustrating the link locking device of a vehicle seat;FIGS.5and6are views schematically illustrating the link locking device for a vehicle before and after a buckle is pulled.

FIGS.1to6show that a link locking device100for a vehicle seat according to an embodiment of the present invention includes a sector gear unit200rotatably fastened to a cushion frame10and fastened to a link connection unit30, to which a height link40provided in a seat rail20is rotatably coupled, to rotate together and a locking unit300rotatably coupled to the cushion frame10and fastened to a buckle50of a seat belt to engage the sector gear unit200and block the rotation of the link connection unit30when the buckle is pulled.

The seat rail20is installed on the floor panel inside the vehicle and is equipped to be movable in the forward and backward directions of the vehicle. One side of the height link40is rotatably coupled to the rear end of the seat rail20while the other side of the height link40is rotatably coupled to the link connection unit30rotatably fastened to the cushion frame10. In other words, the height of the cushion frame10can be adjusted upward and downward with respect to the seat rail20, and the link connection unit30and the height link40rotate when the cushion frame10moves.

Therefore, when at least either of the link connection unit30and the height link40is restrained from rotating, the movement of the cushion frame10is restrained and the distortion of the seat cushion may be prevented.

Accordingly, in the present invention, when the buckle50is pulled due to a collision, the locking unit300engages the sector gear unit200to restrain the link connection unit30from rotating so that the movement of the cushion frame10may be restrained.

To this end, the sector gear unit200is fastened to the link connection unit30rotatably fastened to the cushion frame10and engages the locking unit300to restrain the rotation when the buckle50is pulled.

More specifically, the sector gear unit200includes a sector gear unit main body210fastened to the link connection unit30between the cushion frame10and the height link40and a sector gear220formed from the sector gear unit main body210toward the locking unit300. Here, the sector gear220includes a plurality of sector gear teeths.

The locking unit300is rotatably coupled to the cushion frame10, is fastened to the buckle50of the seat belt, and engages the sector gear220of the sector gear unit200to block the rotation of the link connection unit30when the buckle is pulled.

More specifically, the locking unit300includes a base frame310fastened to the cushion frame10, a rotating member320rotatably fastened to the base frame310and having a pawl gear321to engage the sector gear unit200, a guide link330rotatably fastened to the base frame310and having one side fastened to the buckle50to receive rotational power, and a power transmission unit350rotatably positioned on the base frame310and having one end fastened to the rotating member320and the other end fastened to the guide link330to transmit the rotational power of the guide link330to the rotating member320.

The locking unit300also includes a buckle shaft340positioned through the slot holes11,311formed in the base frame310and the cushion frame10and having one end fastened to the buckle50and the other end rotatably fastened to one side of the guide link330.

In this configuration, the buckle50is positioned on the outside of the cushion frame10and the buckle fastening member51is fastened to one end of the buckle shaft340positioned through both the slot hole11formed in the cushion frame10and the slot hole311formed in the base frame310to fasten the buckle50to the buckle shaft340.

This allows the buckle shaft340to move upward along the slot holes11,311when the buckle50is pulled upward.

Here, the cushion frame10may include a guide bushing12for guiding the movement of the buckle shaft340positioned around the periphery of the slot hole11. The guide bushing12may guide the movement of the buckle shaft340and prevent noise caused by the collision between the buckle shaft340and the cushion frame10.

The base frame310is fastened to the cushion frame10and the slot hole311is formed for the buckle shaft340to be movably inserted thereinto.

The base frame310includes a rotating member hinge portion312to which the rotating member320is rotatably fastened and a guide link hinge portion313to which the guide link330is rotatably fastened.

The base frame310is fastened to the cushion frame10through a fastening member B, which is a bolt. At this time, a plurality of fastening members is screwed to the rotating member hinge portion312and the guide link hinge portion313respectively through the cushion frame10from the outside of the cushion frame10while the base frame310is positioned on the inside of the cushion frame10to fasten the base frame310to the cushion frame10.

The guide link330is inserted and rotatably fastened onto the guide link hinge portion313provided in the base frame310. A buckle shaft340is inserted and fastened into a buckle shaft fastening hole331formed on one side of the guide link while a catch groove332is formed on the other side to catch and support a first support portion352of the power transmission unit350.

The rotating member320is inserted and rotatably fastened onto a rotating member hinge portion312provided in the base frame310, includes a pawl gear321on a surface facing the sector gear unit200, and includes a catch boss322protruding parallel to the rotation axis from the rear of the pawl gear321to catch and support a second support portion353of the power transmission unit350to receive the rotational power.

The power transmission unit350is rotatably positioned on the base frame310and has one end fastened to the rotating member320and the other end fastened to the guide link330to transmit the rotational power of the guide link330to the rotating member320.

In other words, the rotating member320and the guide link330are spaced apart from each other and are connected by the power transmission unit350so that when the guide link330is rotated by the buckle50, the power transmission unit350transmits the rotational power to the rotating member320to rotate the rotating member320. The power transmission unit350may be made of an elastic material to absorb the shock that may occur while transmitting the rotational power and thus allow elastic deformation.

More specifically, the power transmission unit350may include a power transmission unit body351bent into a streamlined shape and positioned in tight contact with the guide unit354fitted onto the rotating member hinge portion312provided concentrically with the rotation axis of the rotating member320, a first support portion352bent toward the rotation axis at one end of the power transmission unit body351to catch on and be supported by a catch groove332formed in the guide link330, and a second support portion353bent toward the sector gear unit200at the other end of the power transmission unit body351to catch on and be supported by a catch boss formed in the rotating member320.

In this configuration, as illustrated inFIG.6, when the buckle50is pulled, the buckle shaft340moves upward to move one side of the guide link330upward and rotate the guide link330around the guide link hinge portion313. As a result, the catch groove332moves upward to activate the power transmission unit350and the power transmission unit350rotates the rotating member320toward the sector gear unit200so that the pawl gear321engages the sector gear220. The locking unit300further includes an elastic member360having one end fastened to the buckle shaft340and the other end fastened to an end of the rotating member hinge portion312provided in the base frame310to apply an elastic force to cause the guide link330rotated by the buckle50to return to its original position.

In this configuration, as illustrated inFIG.6, when the buckle50is pulled, the rotating member320rotates to engage the pawl gear321with the sector gear220so that the elastic member360is stretched to generate an elastic force.

When the force pulling the buckle50is removed, the elastic force of the elastic member360causes the guide link330to return to its original position and the power transmission unit350also returns to its original position so that the pawl gear321is detached from the sector gear220to return to its original position as illustrated inFIG.5.

According to the link locking device of a vehicle seat of the present invention, when the buckle is pulled, the locking unit engages the sector gear unit to restrain the link connection unit from rotating and prevent the rotation of the height link, thereby having the effect of preventing the distortion of the seat cushion.

The present invention is described in detail through specific embodiments above. However, this is intended to serve the purpose of specifically describing the present invention, and it is evident that the present invention is not limited thereto and may be modified and improved upon by those skilled in the art within the technical spirit of the present invention.

All simple modifications and changes of the present invention fall within the scope of the present invention, and the specific scope of protection of the present invention will be made clear by the appended patent claims.

DESCRIPTION OF REFERENCE NUMERALS

10: cushion frame12: guide bushing20: seat rail30: link connection unit40: height link50: buckle100: link locking device for vehicle seat200: sector gear unit210: sector gear unit main body220: sector gear300: locking unit310: base frame312: rotating member hinge portion313: guide link hinge portion320: rotating member321: pawl gear322: catch boss330: guide link331: buckle shaft fastening hole332: catch groove340: buckle shaft350: power transmission unit351: power transmission unit body352: first support portion353: second support portion354: guide unit360: clastic member