JP2013177090A - Shock absorbing unit and reclining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shock absorbing unit capable of being additionally attached to an existing vehicle seat while appropriately absorbing rear collision shock.SOLUTION: A shock absorbing unit includes a shock absorbing member connected to a reclining device, a plate attached to a seat back side, and a bushing for supporting the shock absorbing member and the plate, wherein a recess is formed in a portion that is swollen outward when the shock absorbing member is subject to rear collision shock. Thereby, it suppresses the largest increase of a diameter of the shock absorbing member when absorbing the rear collision shock, and other components around the reclining device are not affected, thus allowing the shock absorbing unit to be additionally attached to an existing vehicle seat.

Description

The present invention relates to an impact absorbing unit used in a reclining device that tilts a seat back with respect to a seat cushion of a vehicle seat.

In general, a vehicle seat is configured such that the inclination of a seat back serving as a back portion can be adjusted with respect to a seat cushion serving as a seat portion by a reclining device, thereby providing a more comfortable seating state for a seated person.

On the other hand, when a rear-end collision occurs in the vehicle, the seated person receives a rear impact that is strongly pressed against the seat back of the vehicle seat, but this rear impact is absorbed to minimize the impact of the rear impact. However, a rear impact shock absorption technique has been proposed in which the inclination of the seat back to the seat cushion is gradually changed.

For example, in the rear impact shock absorbing technique described in Patent Document 1, a vehicle shock absorbing seat is a seat cushion, a seat back that can tilt with respect to the seat cushion, and a headrest that is installed above and below the seat back. It has.

The seat frame that serves as the skeleton of the seat cushion and the back frame that serves as the skeleton of the seat back are coupled by a back base end frame that is rotatably installed at the end of the seat frame, so that the seat back is seat cushion. It is possible to tilt with respect to.

In such a configuration, the vehicle impact absorbing sheet is characterized in that a portion where the back frame is fixedly connected to the back base end frame is an impact absorbing portion.

This shock absorbing part is provided at the overlap between the back base frame and the back frame at both ends and the center in the longitudinal direction of the overlap, and a fuse mechanism based on fixing and fastening both with bolts and nuts, and rebound A suppression element and a fulcrum part are provided.

The fuse mechanism includes a fuse bolt inserted through the fixing hole provided in the back frame without play, an insertion hole provided in the back base end frame through which the fuse bolt is inserted without play under normal conditions, and A slot-like fuse hole provided with a tapered shock absorbing groove that is once provided and has a diameter that is smaller than the insertion hole and that gradually increases to the diameter of the insertion hole.

The rebound suppression element is a rebound suppression bolt that has a small-diameter tip side inserted without play by a fixing hole provided in the back frame, and has a large-diameter portion on the lower side of the neck. A long hole-shaped rebound suppressor with an insertion hole that is inserted continuously without play and a large diameter hole that is provided continuously therethrough and allows the rebound suppression bolt to be inserted without play through the lower diameter neck of the rebound restraint bolt when absorbing a rear impact. And a hole.

The fulcrum portion includes a fulcrum bolt that is inserted through a fixing hole provided in the back frame without play, and a fulcrum hole that is provided at the back base frame and is always inserted without play.

When the rear impact is received, the back frame is tilted backward with respect to the back base frame, and in this case, the shock absorbing portion is centered on the fulcrum portion and the fuse mechanism and the rebound suppressing element are within the long hole. Allow the frame to tilt backwards, and then absorb the rear impact energy during the tilting.

That is, the fuse mechanism absorbs rearward rear impact energy by moving the inside of the fuse hole in the large diameter direction while the fuse bolt expands and deforms the fuse hole.

Thus, according to the vehicle impact absorbing sheet having the impact absorbing portion, the impact energy at the time of the rear impact is surely absorbed by the fuse mechanism, and the rebound movement of the upper body of the seated person is ensured by the rebound suppressing element. To be suppressed.
JP 10-309968

However, the above-described shock absorbing sheet for a vehicle has a problem that it cannot be retrofitted to a conventional seat because the shock absorbing portion is provided integrally with the seat back frame.

The present invention has been made to solve the above-described problems, and an object thereof is to provide an impact absorbing unit and a reclining device that can be retrofitted to an existing vehicle seat while preferably absorbing a rear impact. There is to do.

In order to solve the above-mentioned problem, according to the invention of claim 1, an impact absorbing unit assembled in a reclining device for tilting a seat back with respect to a seat cushion of a vehicle seat, the impact coupled to the reclining device. An absorbing member, a plate attached to the seat back side, and the shock absorbing member and a bush that supports the plate are formed, and a recess is formed in a portion that expands outward when the shock absorbing member receives a rear impact. It is characterized by that.

A second aspect of the present invention is the shock absorbing unit according to the first aspect, wherein the bush is provided outside a welding position of the reclining device and the shock absorbing member.

A third aspect of the present invention is the shock absorbing unit according to the first aspect, wherein the reclining device, the shock absorbing member, the plate, and the bush are assembled, and then the vehicle seat back side is assembled. It is attached to the bracket.

According to the first aspect of the present invention, there is provided an impact absorbing unit that is assembled to a reclining device that tilts the seat back with respect to the seat cushion of the vehicle seat, and is attached to the seat back side, an impact absorbing member coupled to the reclining device. A plate, a shock absorbing member, and a bush supporting the plate are provided, and a recess is formed in a portion that expands outward when the shock absorbing member receives a rear impact. As a result, when the rear impact impact is absorbed, the increase in the maximum diameter of the impact absorbing member can be suppressed, and impact absorption that can be retrofitted to an existing vehicle seat without affecting other parts around the reclining device. Units can be provided.

The invention of claim 2 is characterized in that the bush is provided outside the welding position of the reclining device and the shock absorbing member. The shock absorbing unit of the present invention is assembled by providing a gap between the plate and the shock absorbing member in order to cope with deformation in the thickness direction when the shock absorbing member absorbs the shock. For this reason, spatter or the like may enter the gap between the plate and the impact absorbing member during welding fixation, and the impact absorbing amount of the impact absorbing member may be affected when the impact is absorbed after the impact is absorbed. In order to prevent these, by providing a bush outside the welding position of the reclining device and the impact absorbing member, it is possible to prevent spatter generated during welding from entering the gap.

The invention according to claim 3 is characterized in that the reclining device, the impact absorbing member, the plate, and the bush are assembled and then assembled to a seat back side bracket of a vehicle seat. With this structure, an existing reclining device that does not use shock absorbing members can be installed on existing vehicle seats by simply installing shock absorbing members and plates that take into account the dimensions of each member and related parts. It is possible to provide a shock absorbing unit that is versatile and can be easily installed later.

It is an exploded perspective view of a reclining device. It is a side view of a reclining device. It is a front view of an impact-absorbing member

Hereinafter, an embodiment of a vehicle seat on which a reclining device to which an impact absorbing member according to the present invention is applied will be described with reference to the drawings.

The vehicle seat provided with the impact absorbing member of the present invention includes a seat cushion that receives a seated portion of the seated person, and a seat back that can tilt with respect to the seat cushion and receive the seated person's back.

A seat frame serving as a skeleton of the seat cushion and a back frame serving as a skeleton of the seat back are coupled by a reclining device installed at an end of the seat frame, and the seat is operated according to an operation of an operation lever of the reclining device. The back can be tilted with respect to the seat cushion.

As shown in FIG. 1, the reclining device 5 includes a bush 1, a plate 2, an impact absorbing member 3, and a reclining mechanism 4.

The reclining mechanism 4 includes a main body frame 4a and a rotation shaft 4b supported so as to be rotatable relative to the main body frame 4a. The main body frame 4a is formed so as to be fixed to the seat frame. In addition, a plurality of protrusions 4c for connecting to the shock absorbing member 3 are formed at equal intervals in the circumferential direction on the seat back side.

The rotation shaft 4b is configured to rotate relative to the main body frame 4a by the operation of the operation lever, and a serration portion 4d is formed at the tip of the rotation shaft 4b. The serration portion 4d is inserted into the connecting shaft of the back frame so that the rotation phase can be adjusted, so that the back frame and the rotation shaft 4b are synchronously rotated around the rotation shaft 4b. .

The shock absorbing member 3 is manufactured by sheet metal processing from an appropriately flexible steel plate, and the plate thickness of the steel plate used as a material is subject to a rear-end impact as a part of the shock absorbing member 3 will be described later. It is determined in view of the fact that it can be plastically deformed and then absorb impact energy.

As shown in FIG. 3, the impact absorbing member 3 includes a concave annular rim portion 31, a substantially annular hub portion 32, six first spoke portions 33, and three narrow second spoke portions 34. A part of the inner edge of the rim part 31 and a part of the outer edge of the hub part 32 are coaxially rotatable on the same plane by the spoke parts 33 and are integrally connected.

In the rim portion 31, six through holes 31a corresponding to the through holes 2b are formed at equal intervals in the circumferential direction between portions connected to the spoke portions 33.

The hub portion 32 is formed with a through hole 32a for connecting to each protrusion 4c of the reclining device 4.

The rim portion 31 that is the outer peripheral side of the shock absorbing member 3 is connected to the seat frame through the reclining mechanism 4, and the hub portion 32 that is the inner peripheral side of the shock absorbing member 3 is connected to the seat back side plate 2. Connected to the back frame. For this reason, for example, when a rear impact that causes the seat back to tilt backward due to the seated passenger in the rear-loaded vehicle being strongly pressed against the seat back of the vehicle seat or the like is applied to the hub portion 32, On the other hand, a rotational force that rotates in the clockwise direction in FIG. 3 (hereinafter referred to as the backward rotation direction α) acts.

In order to alleviate the rotational force, a substantially V-shaped deformed portion 33a is provided on the opposite side of the reverse rotation direction α as shown in FIG. The two-spoke part 34 forms a notch 34a on the opposite side to the backward rotation direction α.

In the plate 2, a central disk portion 2a and six through holes 2b for connecting the shock absorbing member 3 to the outer periphery are formed at equal intervals in the circumferential direction. Further, the center disk portion 2a is formed to be able to engage with the outer peripheral surface of the bush 1 on the inner peripheral surface thereof.

The reclining device 5 configured as described above is assembled as follows. First, after the bush 1 is fitted to the central disk portion 2a of the plate 2, the rotating shaft 4d of the reclining mechanism 4 is inserted into the bush 1 and each projection of the reclining mechanism 4 is inserted into each through hole 32a of the shock absorbing member 3. The shock absorbing member 3 is fixed to the body frame 4a of the reclining mechanism by engaging and welding the 4c. Then, the shock absorbing member 3 is fixed to the plate 2 by caulking with a rivet or the like in a state where the through hole 31a of the shock absorbing member 3 and the through hole 2b of the plate 2 are aligned. Thereby, the reclining device 5 shown in FIG. 2 is completed.

At this time, the reclining device 5 is assembled by providing a gap between the plate 2 and the shock absorbing member 3 in order to cope with deformation in the thickness direction when the shock absorbing member 3 absorbs the shock. Therefore, there is a possibility that spatter and the like at the time of welding fixing enter the gap between the plate 2 and the shock absorbing member 3 and affect the shock absorption amount of the shock absorbing member 3 when absorbing the impact after the impact. Therefore, in this configuration, the bush 1 is assembled outside the welding position of the reclining mechanism 4 and the impact absorbing member 3. As a result, the bush 1 serves as a lid for the gap between the plate 2 and the shock absorbing member 3, and prevents spatter generated during welding of the shock absorbing member 3 and the reclining mechanism 4 from entering the gap. It becomes possible.

Further, since the reclining device 5 is configured without using a bracket or the like on the seat back side of the vehicle seat, with respect to an existing reclining device that does not employ the shock absorbing member 3, Therefore, it is possible to provide a general-purpose shock absorbing unit that can be easily retrofitted to an existing vehicle seat by simply mounting the shock absorbing member 3 and the plate 2 in consideration of related parts.

Further, since the rim portion 31 and the hub portion 32 of the shock absorbing member 3 can be coaxially rotated by the spoke portions 33 and 34 and are integrally connected, each member is assembled as a separate member, and the shock is absorbed. Compared with the case where the absorption unit is configured, a decrease in the assembling workability of the reclining device 5 due to the use of the shock absorbing member 3 is suppressed.

Next, the function and effect of the shock absorbing member 3 will be described. When the rear impact as described above does not act on the seat back, the relative rotation position between the rim portion 31 and the hub portion 32 is maintained, and the spoke portions 33 and 34 are not plastically deformed.

On the other hand, for example, when a rear impact that causes the seat back to tilt backward is caused by a seated person in the rear-projected vehicle being strongly pressed against the seat back of the vehicle seat, the seat back side Rotational force that causes the hub portion 32 of the shock absorbing member 3 to rapidly rotate in the backward rotation direction α is exerted via the plate 2. And since the main body frame 4a of the reclining mechanism 4 and the rim part 31 of the shock absorbing member 3 connected to the seat part frame of the seat cushion maintain the current rotation position, the turning force is applied to each of the spoke parts 33, 34. Of these, only the portion connected to the hub portion 32 is rotated.

Here, a narrow portion 33b, a rupture portion, in which a circumferential width is narrowed by forming a deformed portion 33a and a notch portion 34a on the anti-reverse rotation direction side at a radial intermediate portion of each spoke portion 33, 34 34b is provided. Then, the fracture portion 34b is plastically deformed according to the rotational force, the second spoke portion is fractured, and plastic deformation of the narrow portion 33b is started according to the rotational force.

Further, when the first spoke portion 33 starts to be plastically deformed, the vicinity of the narrow portion 33b moves in the backward rotation direction α, so that the deformable portion 33a is plastically deformed so as to be crushed. If each side neck portion 33a is crushed and both surfaces constituting the deformable portion 33a come into contact with each other, plastic deformation in the vicinity of the narrow portion 33b stops unless a further rear impact is applied. The relative rotation of the portion 32 stops at a predetermined rotation angle, and the rearward tilting of the seat back stops.

As described above, since the narrow portion 33b and the fractured portion 34b are gradually plastically deformed, the rotational force, that is, the rear impact that acts on the seat back can be suitably absorbed by the plastic deformation.

Further, since the shock absorbing member 3 includes the concave annular rim portion 31, it is possible to suppress an increase in the maximum diameter of the shock absorbing member when the rear impact is suitably absorbed by plastic deformation of each spoke portion. And other parts around the reclining device are not affected.

As the rear impact impact assumed here increases, the rear impact impact is preferably increased by setting the circumferential width dimension of the narrow portion 33b of the first spoke portion 33 and the fracture portion 34b of the second spoke portion 34 to be larger. Can be absorbed. Further, the width dimension of the notch portion 34a of the second spoke portion 34 is based on a rotation angle at which relative rotation between the hub portion 32 and the rim portion 31 is allowed when an impact that tilts the seat back backward is applied. Is set.

As described above, in the impact absorbing member 3 according to the present embodiment, the rim portion 31 connected to the seat cushion via the reclining mechanism 4 or the like is on the outer peripheral side, and the seat back via the seatback side plate 2 or the like. Both members 31 and 32 are connected by the spoke portions 33 and 34 so as to be coaxially rotatable so that the hub portion 32 to be connected is on the inner peripheral side. The first spoke portion 33 is formed with a narrow portion 33b having a circumferential width narrowed by providing the deformed portion 33a, and the second spoke portion 34 is formed with a notch portion 34a and a fracture portion 34b. Has been.

As a result, when the turning force corresponding to the rear impact is applied as described above, the fracture portion 34b of the second spoke portion 34 is broken according to the turning force without first deforming the first spoke portion 33. Therefore, the head of the occupant who is seated can be restrained early. Thereafter, the rear impact impact acting on the seat back can be suitably absorbed by the deformation portion 33a of the first spoke portion 33 being plastically deformed. In addition, by providing a recess in the portion that deforms outward when the impact absorbing member 3 receives a rear impact, there is no change in the maximum diameter of the impact absorbing member 3 when absorbing the impact, and the reclining device 4 It does not affect other parts around.

1 bush
2 plates
3 Shock absorbing member
4 Reclining device
31 Rim part
32 Hub part
33 First spoke
34 Second spoke part α Reverse rotation direction

Claims (3)

An impact absorbing unit assembled in a reclining device for tilting a seat back with respect to a seat cushion of a vehicle seat, the impact absorbing member connected to the reclining device, a plate attached to the seat back side, and the impact absorbing member And a bush that supports the plate, and a recess is formed in a portion that expands outward when the impact absorbing member receives a rear impact. 2. The shock absorbing unit according to claim 1, wherein the bush is provided outside a welding position of the reclining device and the shock absorbing member. 2. The impact absorbing unit according to claim 1, wherein the reclining device, the impact absorbing member, the plate, and the bush are assembled and then assembled to a seat back side bracket of a vehicle seat. Shock absorption unit.

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