WO2013161386A1

WO2013161386A1 - Vehicle seat

Info

Publication number: WO2013161386A1
Application number: PCT/JP2013/055521
Authority: WO
Inventors: 慎二上原
Original assignee: 日本発條株式会社
Priority date: 2012-04-27
Filing date: 2013-02-28
Publication date: 2013-10-31
Also published as: JP5728428B2; JP2013230742A

Abstract

In this vehicle seat (10), a wire (100) of a guide mechanism (70) is disposed on a rear guide surface (94) side of a rear guide (90). The cross section of a linking gear (102) thereby has a fan shape, whereby the ratio of the radius of the linking gear (102) to the radius of the wire (100) can be increased. Therefore, when a back shell (54) slides in the vertical direction of the seat relative to a seat back frame, the linking gear (102) is rotated stably about the wire (100) as an axial center, and the sliding action of the back shell (54) relative to the seat back frame can therefore be stabilized.

Description

Vehicle seat

The present invention relates to a vehicle seat having a back shell.

In the vehicle seat described in Patent Document 1 below, the back shell is connected to the back frame by a back support mechanism and is slidable in the vertical direction with respect to the back frame.

The back support mechanism includes a cam follower (rotary body) provided on the back shell side and a guide rail (guide member) provided on the back frame side, and the back shell moves up and down with respect to the back frame. When sliding in the direction, the cam follower moves in the guide rail.

Special table 2008-526425

However, in this back support mechanism, when the cam follower moves in the guide rail, the cam follower rolls with respect to the inner surface of the guide rail, but the cam follower is stably rotated (the back shell is stable with respect to the back frame). There is room for improvement.

The present invention is intended to provide a vehicle seat that can stabilize the sliding motion of the back shell relative to the seat back frame in consideration of the above facts.

The vehicle seat according to the first aspect is provided on the back shell of the back shell, which supports the back of the seated occupant and is slidable in the seat back vertical direction with respect to the seat back frame, A guide member that has a front guide surface and a rear guide surface that extend in the vertical direction of the seat back and that are disposed opposite to each other in the longitudinal direction of the seat back, and guides the sliding movement of the back shell with respect to the seat back frame; And is disposed between the front guide surface and the rear guide surface toward one side of the front guide surface and the rear guide surface, with respect to the guide member. A shaft portion that is relatively movable in the vertical direction of the seat back, and the shaft portion Relatively rotatably provided, and a, a rotating body that is movable in rolling with respect to the other of said front guide surface and the rear guide surface.

In the vehicle seat according to the first aspect, a guide member is provided on the back surface of the back shell. The guide member has a front guide surface and a rear guide surface, and each of the front guide surface and the rear guide surface is disposed so as to oppose the seat back longitudinal direction and extends in the seat back vertical direction.

And a shaft portion is arranged between the front guide surface and the rear guide surface. The shaft portion is disposed with the seat width direction as an axial direction, and is coupled to the seat back frame so as to be movable relative to the guide member in the seat back vertical direction.

Here, the shaft portion is provided with a rotating body so as to be relatively rotatable, the shaft portion is disposed near one side of the front guide surface and the rear guide surface, and the rotating body is the other of the front guide surface and the rear guide surface. It is made possible to roll against. Thereby, for example, the ratio of the radius of the rotating body to the radius of the shaft portion can be set large by making the section of the rotating body a fan shape. For this reason, when the back shell slides with respect to the seat back frame, the rotating body is stably rotated relative to the shaft portion, so that the back shell can slide stably with respect to the seat back frame.

A vehicle seat according to a second aspect is the vehicle seat according to the first aspect, wherein the shaft portion is in contact with the rear guide surface, and the rotating body is capable of rolling with respect to the front guide surface. Has been.

In the vehicle seat according to the second aspect, the shaft portion is in contact with the rear guide surface, and the rotating body is configured to be able to roll with respect to the front guide surface. Generation of backlash between the front guide surface and the rotating body can be suppressed. That is, the backlash in the back-and-forth direction of the seat back relative to the seat back frame in the back shell can be suppressed.

Moreover, since the rear guide surface is disposed rearward of the seat back with respect to the front guide surface, the load on the seat rear side acting on the back shell from the seat occupant when the back shell supports the back of the seat occupant is mainly Acting between the front guide surface and the rotator, the rotator rolls relative to the front guide surface. That is, since this load is suppressed from acting between the shaft portion and the rear guide surface, the sliding resistance between the shaft portion and the rear guide surface when the back shell slides with respect to the seat back frame is reduced. it can.

A vehicle seat according to a third aspect is the vehicle seat according to the second aspect, wherein the vehicle member is formed on the guide member, extends in a seat back vertical direction, is formed on the rotating body, and meshes with the rack. And a pinion.

In the vehicle seat according to the third aspect, a rack is formed on the guide member, and a pinion meshed with the rack is formed on the rotating body. For this reason, when the back shell slides relative to the seat back frame, the rotating body is reliably rotated relative to the shaft portion by the rack and the pinion, and rolls with respect to the front guide surface. As a result, the back shell can slide more stably with respect to the seat back frame.

In the vehicle seat according to the fourth aspect, in the vehicle seat according to the second aspect or the third aspect, the rear guide surface and the shaft portion are in point contact.

In the vehicle seat according to the fourth aspect, since the rear guide surface and the shaft portion are in point contact, the sliding resistance between the rear guide surface and the shaft portion when the back shell slides with respect to the seat back frame. Can be further reduced.

A vehicle seat according to a fifth aspect is the vehicle seat according to any one of the second to fourth aspects, wherein the rotating body is formed in a fan-shaped column shape, and both circumferential ends of the rotating body are formed. A non-interference portion that does not interfere with the guide member is formed on the surface.

In the vehicle seat according to the fifth aspect, the rotating body is formed in a fan-shaped column shape. Here, the non-interference part which does not interfere with a guide member is formed in the circumferential direction both end surfaces of a rotary body. Thereby, the radius of the rotating body corresponding to the movement stroke of the back shell can be set large.

A vehicle seat according to a sixth aspect is the vehicle seat according to any one of the second to fifth aspects, wherein the guide member is fixed to the back shell and the front guide A front guide having a surface and a rear guide having the fitting portion to be fitted to the front guide are formed while the rear guide surface is formed.

In the vehicle seat according to the sixth aspect, the guide member includes a front guide fixed to the back shell and a rear guide. That is, the guide member is configured to be divided into a front guide and a rear guide. A front guide surface is formed on the front guide. The rear guide has a rear guide surface and a fitting portion, and the fitting portion is fitted to the front guide.

As a result, after fixing the front guide to the back shell, the back shell is connected to the seat back frame by placing the shaft and rotating body behind the seat back of the front guide and fitting the rear guide to the front guide. Is done. Therefore, the back shell can be easily connected to the seat back frame.

A vehicle seat according to a seventh aspect is the vehicle seat according to any one of the first to sixth aspects, wherein a pair of the guide member and the rotating body are provided in the seat width direction. .

In the vehicle seat according to the seventh aspect, since the guide member and the rotating body are provided in a pair in the seat width direction, the sliding motion of the back shell with respect to the seat back frame can be effectively stabilized.

The vehicle seat according to the first aspect can stabilize the sliding motion of the back shell relative to the seat back frame.

According to the vehicle seat pertaining to the second aspect, backlash in the back and forth direction of the back shell relative to the seat back frame can be suppressed, and the rear guide surface and the shaft portion when the back shell slides relative to the seat back frame can be suppressed. The sliding resistance can be reduced.

According to the vehicle seat pertaining to the third aspect, the sliding motion of the back shell relative to the seat back frame can be further stabilized.

According to the vehicle seat pertaining to the fourth aspect, the sliding resistance between the rear guide surface and the shaft portion when the back shell slides relative to the seat back frame can be further reduced.

According to the vehicle seat according to the fifth aspect, the radius of the rotating body corresponding to the movement stroke of the back shell can be set large.

According to the vehicle seat according to the sixth aspect, the back shell can be easily connected to the seat back frame.

According to the vehicle seat pertaining to the seventh aspect, the sliding movement of the back shell relative to the seat back frame can be effectively stabilized.

It is the perspective view seen from the sheet | seat left diagonal back which shows the guide mechanism used for the vehicle seat which concerns on embodiment of this invention. FIG. 2 is a partially broken perspective view of the vehicle seat according to the embodiment of the present invention as seen from the left front side of the seat. FIG. 3 is a perspective view of the back shell shown in FIG. It is a perspective view which shows the front guide shown by FIG. It is a perspective view which shows the connection gear shown by FIG. It is a perspective view which shows the rear guide shown by FIG. FIG. 5 is a cross-sectional view of the guide mechanism shown in FIG. 1 as viewed from the left side of the seat (cross-sectional view taken along line 5-5 in FIG. 1). FIG. 6 is an enlarged cross-sectional view of the rear guide shown in FIG. 5 as viewed from above the seat (cross-sectional view taken along line 6-6 in FIG. 5).

FIG. 2 is a partially broken perspective view of the entire vehicle seat 10 according to the embodiment of the present invention as viewed from the front left of the seat. Note that an arrow FR appropriately shown in the drawings indicates the front of the seat, an arrow RH indicates the right side of the seat (one side in the seat width direction), and an arrow UP indicates the upper side of the seat.

As shown in this figure, the vehicle seat 10 includes a seat cushion 30 on which an occupant is seated, a seat back 50 that supports the back of the occupant, a connecting mechanism 12 that connects the seat cushion 30 to a vehicle body floor (not shown), It is comprised including. The seat back 50 is disposed in an upright state at the seat rear side end portion of the seat cushion 30, and the seat back vertical direction and the seat vertical direction coincide with each other, and the seat back longitudinal direction and the seat longitudinal direction are Have been matched.

(About the coupling mechanism 12)

The connecting mechanism 12 constitutes the lower part of the vehicle seat 10. The coupling mechanism 12 has a pair of long guide rails 14, and the guide rails 14 are arranged in parallel with the longitudinal direction being the front-rear direction of the seat. Further, both end portions in the longitudinal direction of the guide rail 14 are fixed to the vehicle body floor of the vehicle via a pair of leg brackets 16.

A long upper rail (not shown) is provided in each of the pair of guide rails 14, and the upper rail is configured to be slidable in the front-rear direction of the seat with respect to the guide rail 14. Seat cushion frames 18 are respectively provided on the upper rails. The seat cushion frame 18 is made of sheet metal, and the lower portion of the seat cushion frame 18 is fixed to the upper rail by fastening members such as bolts and nuts (not shown). Thereby, the seat cushion frame 18 is configured to be movable in the seat front-rear direction integrally with the upper rail.

The seat cushion frame 18 is provided with a pair of links 20 for supporting a seat cushion 30 to be described later, and the lower end of the link 20 can rotate to the seat cushion frame 18 with the axial direction as the seat width direction. It is supported by.

Further, a support panel 22 is provided between the pair of seat cushion frames 18. The support panel 22 is formed in a substantially rectangular plate shape, and is bridged (connected) to the pair of seat cushion frames 18 with the plate thickness direction being the seat vertical direction.

(About the seat cushion 30)

The seat cushion 30 is provided on the seat upper side of the seat cushion frame 18. The seat cushion 30 has a cushion shell 32. The cushion shell 32 is formed in a substantially plate shape, and is disposed with the plate thickness direction being substantially the seat vertical direction. The upper end portion of the link 20 described above is connected to the lower portion of the cushion shell 32 in the seat width direction so that the axial direction is the seat width direction, so that the cushion shell 32 is connected to the seat cushion frame 18. Thus, it is configured to be movable in the seat vertical direction and the seat longitudinal direction. Further, at both ends of the cushion shell 32 in the seat width direction, support shafts 34 for supporting a back shell 54 described later are provided at positions behind the seat, and the support shaft 34 has the axial direction as the seat width direction. It protrudes outward in the seat width direction from the cushion shell 32 (in FIG. 2, only the support shaft 34 on the left side of the seat is shown). Further, a urethane pad 36 is provided on the upper side of the cushion shell 32. The thickness of the urethane pad 36 is set to be relatively thin, and the urethane pad 36 is covered with a skin 38.

On the other hand, a support pad 40 (which is an element grasped as an “elastic body” in a broad sense) is provided between the cushion shell 32 and the support panel 22. The support pad 40 is made of a soft foam synthetic resin or the like, is formed in a substantially rectangular parallelepiped shape, and is in contact with the cushion shell 32 and the support panel 22. As a result, the cushion shell 32 is supported by the support panel 22 via the support pad 40. When an occupant sits on the cushion shell 32, the cushion shell 32 presses the support pad 40 to the lower side of the seat, thereby supporting the cushion shell 32. The pad 40 is configured to be elastically deformed. Further, at this time, the cushion shell 32 moves to the lower side of the seat following the elastic deformation of the support pad 40, and an elastic force to the upper side of the seat acts from the support pad 40 to the cushion shell 32 (applied). It is configured as follows.

(About the seat back 50)

The seat back 50 includes a seat back frame 52, a back shell 54, and a pair of guide mechanisms 70 (see FIG. 3).

The seat back frame 52 is configured as a part of the skeleton member of the seat back 50. The seat back frame 52 is made of a pipe material, and is bent into a substantially inverted U shape that is opened to the lower side of the seat when viewed from the front of the seat. The left end portion of the seat back frame 52 is rotatably supported by the rear end portion of the seat cushion frame 18 with the axial direction being the seat width direction. On the other hand, an end portion on the right side of the seat back frame 52 is rotatably connected to the seat cushion frame 18 via a conventionally known reclining mechanism (not shown).

The back shell 54 is formed in a substantially plate shape. The back shell 54 is disposed inside the seat back frame 52 when viewed from the front of the seat, with the plate thickness direction being the front-rear direction of the seat. A pair of hinge brackets 56 are fixed to the lower back of the back shell 54 (only the hinge bracket 56 on the left side of the seat is shown in FIG. 2). The hinge bracket 56 extends in the vertical direction of the seat and extends outward from the lower end portion in the seat width direction. The end of the hinge bracket 56 on the outer side in the seat width direction is rotatably supported by the support shaft 34 of the cushion shell 32 described above with the axial direction being the seat width direction. Thus, when the back shell 54 is connected to the cushion shell 32 by the hinge bracket 56 and the cushion shell 32 is moved in the seat vertical direction, the back shell 54 is moved in the seat vertical direction together with the cushion shell 32. It is configured. That is, the back shell 54 is configured to be slidable (relative movement) in the seat vertical direction with respect to the seat back frame 52.

Furthermore, a urethane pad 64 is provided on the seat front side of the back shell 54. The thickness of the urethane pad 64 is set to be relatively thin, and the urethane pad 64 is covered with a skin 66.

As shown in FIGS. 3 and 5, a pair of fixing recesses 58 are formed on the back shell 54 at both sides in the seat width direction, and the fixing recesses 58 protrude to the rear side of the seat. A concave shape opened to the front side of the seat is formed. A head portion of a weld bolt 60 for fixing a later-described front guide 74 is fixed in the fixing recess 58, and a threaded portion of the weld bolt 60 protrudes from the fixing recess 58 to the seat rear side.

Next, the configuration of the pair of guide mechanisms 70, which is a main part of the present invention, will be described.

As shown in FIGS. 1, 3, and 5, the pair of guide mechanisms 70 are provided at the upper part of the back surface of the back shell 54 and arranged side by side in the seat width direction. The guide mechanism 70 includes a guide member 72, a wire 100 as “shaft”, and a connecting gear 102 as “rotating body”. The guide member 72 has a front guide 74 and a rear guide 90.

The front guide 74 is made of resin. The front guide 74 has a substantially rectangular plate-like main body portion 76, and the main body portion 76 has a plate thickness direction in the seat front-rear direction and a longitudinal direction in the seat up-down direction. It is arranged on the rear side of 58 seats. As shown in FIG. 4A, a fixed recess 78 is formed at the upper and lower portions of the main body 76, respectively, and the fixed recess 78 is formed in a circular shape in cross section to the rear side of the seat. It has an open concave shape. A circular through hole 80 is formed in the bottom wall of the fixed recess 78. Then, as shown in FIG. 5, the threaded portion of the weld bolt 60 is inserted into the through hole 80, and the nut 62 is screwed into the threaded portion of the weld bolt 60, so that the main body portion 76 (front guide 74). Is fixed (fastened) to the back shell 54. Accordingly, the front guide 74 is moved in the seat vertical direction integrally with the back shell 54.

The seat rear side surface of the main body 76 is a front guide surface 82, and the front guide surface 82 is disposed in a direction perpendicular to the front-rear direction of the seat (substantially parallel to the back shell 54).

Also, the front guide 74 is formed with a pair of racks 84 on both sides of the main body 76 in the seat width direction. The rack 84 extends in the vertical direction of the seat and is formed integrally with the main body 76. The rack 84 is composed of a plurality of rack teeth, and the pitch line of the rack 84 coincides with the front guide surface 82 in a side view. Further, a pair of fitted portions 86 for assembling a rear guide 90 described later are formed on the upper end portion and the lower end portion of the main body portion 76. The fitted portion 86 is formed in a substantially rectangular plate shape and protrudes from the main body portion 76 to the upper side and the lower side of the seat, and the rear side surface of the fitted portion 86 is flush with the front guide surface 82. Is arranged.

As shown in FIGS. 1 and 5, the rear guide 90 is formed in a substantially long plate shape, and is disposed so as to be opposed to the rear side of the front guide 74 with the longitudinal direction being the vertical direction of the seat. Further, both end portions in the longitudinal direction of the rear guide 90 are bent toward the front side of the seat, and are formed wider toward the front side of the seat as viewed from above the seat. A fitting hole 92 as a “fitting part” is formed at the tip of each end portion in the longitudinal direction (see FIG. 4C), and the fitting hole 92 has a substantially rectangular shape. The sheet is penetrated in the vertical direction. The fitted portion 86 of the front guide 74 is fitted in the fitting hole 92. As a result, the rear guide 90 is assembled to the front guide 74 and moved in the seat vertical direction integrally with the front guide 74 and the back shell 54.

Further, as shown in FIG. 5, the surface of the rear guide 90 that faces the front guide surface 82 is a rear guide surface 94, and the rear guide surface 94 is disposed in parallel with the front guide surface 82. Further, the rear guide 90 is formed with a pair of beads 96 (elements grasped as “contact portions” in a broad sense) constituting a part of the rear guide surface 94 along the seat vertical direction, The bead 96 is formed in a substantially semicircular cross section and protrudes from the rear guide surface 94 to the front side of the seat (see FIG. 6).

As shown in FIGS. 3 and 5, the wire 100 is formed in a round bar shape and extends along the seat width direction, and both longitudinal ends of the wire 100 are coupled to the seat back frame 52 by welding or the like. Yes. The wire 100 is disposed near the rear guide surface 94 between the front guide surface 82 and the rear guide surface 94, and the outer periphery of the wire 100 is in contact with the bead 96 of the rear guide 90 (see FIG. 6). That is, the axial center of the wire 100 is disposed closer to the rear guide surface 94 than the virtual center plane C disposed at an equal distance from the front guide surface 82 and the rear guide surface 94 (see FIG. 5). Thus, the wire 100 is configured to be point-contacted with the rear guide 90 and to be movable relative to the front guide 74 and the rear guide 90 in the seat vertical direction.

As shown in FIGS. 1 and 5, the connecting gear 102 is made of resin. The connection gear 102 is formed in a substantially sectoral column shape, and is disposed between the front guide surface 82 and the rear guide surface 94 with the height direction (axial direction) being the seat width direction.

A support hole 104 having a substantially C-shaped cross section is formed in the axial center portion of the connection gear 102, and the support hole 104 is formed to penetrate in the sheet width direction and open to the rear side of the sheet. A wire 100 is inserted into the support hole 104. Accordingly, the connection gear 102 is supported by the wire 100 so as to be relatively rotatable, and is configured to be relatively movable with respect to the front guide 74 and the rear guide 90 in the seat vertical direction.

As shown in FIGS. 4B and 5, the outer peripheral surface of the connecting gear 102 is a rolling surface 106, and the rolling surface 106 is curved in an arc shape centering on the support hole 104 in a side view. Thus, the front guide surface 82 of the front guide 74 is in contact with the front guide surface 82. Further, a pair of pinions 108 are formed on the outer peripheral portion of the connecting gear 102 on both sides of the rolling surface 106 in the sheet width direction, and the pinion 108 is constituted by a plurality of pinion teeth. The pitch circle of the pinion 108 is aligned with the rolling surface 106 in a side view, and the pinion 108 is meshed with the rack 84 of the front guide 74 described above. Accordingly, when the back shell 54 slides (relatively moves) in the seat vertical direction with respect to the seat back frame 52, the connecting gear 102 is rotated around the axis of the wire 100 by the rack 84 and the pinion 108 ( The arrow A and the arrow B in FIG. 5 are configured to roll with respect to the front guide surface 82.

Further, non-interfering concave portions 110 as “non-interfering portions” are formed on both end surfaces in the circumferential direction of the coupling gear 102 in the intermediate portion in the axial direction. The non-interference recess 110 is opened outward in the radial direction of the connecting gear 102 and is opened outward in the circumferential direction of the connecting gear 102. When the back shell 54 is slid to the upper side of the seat with respect to the seat back frame 52, the rear guide 90 is disposed in one non-interference recess 110, and interference between the connecting gear 102 and the rear guide 90 is avoided. In addition, the other non-interference recess 110 and the threaded portion of the weld bolt 60 below the seat are configured not to interfere with each other. Further, when the back shell 54 is slid most downward with respect to the seat back frame 52, the rear guide 90 is disposed in the other non-interference recess 110, and interference between the connecting gear 102 and the rear guide 90 occurs. While avoiding, one non-interference recessed part 110 and the thread part of the weld bolt 60 of the sheet | seat upper side are comprised so that it may not interfere.

Next, the operation and effect of this embodiment will be described.

In the vehicle seat 10 configured as described above, when the occupant sits on the seat cushion 30, the cushion shell 32 presses the support pad 40 toward the lower side of the seat by the weight of the occupant, and the support pad 40 is elastically deformed. Accordingly, the cushion shell 32 is moved to the lower side of the seat following the elastic deformation of the support pad 40, and an elastic force to the upper side of the seat acts from the support pad 40 to the cushion shell 32.

Further, the back shell 54 is connected to the cushion shell 32 by a hinge bracket 56. For this reason, when the cushion shell 32 moves to the lower side of the seat, the back shell 54 is moved to the lower side of the seat together with the cushion shell 32.

When the back shell 54 is moved to the lower side of the seat, the front guide 74 (rack 84) and the rear guide 90 are slid (relatively moved) to the lower side of the seat with respect to the wire 100 (the seat back frame 52) together with the back shell 54. The As a result, the rack 84 of the front guide 74 and the pinion 108 of the coupling gear 102 cause the coupling gear 102 to rotate relative to the wire 100 in the direction of arrow A in FIG. 5, and the rolling surface 106 of the coupling gear 102 moves to the front. Roll on the front guide surface 82 of the guide 74. That is, the connecting gear 102 rolls with respect to the front guide surface 82.

In this state, for example, when vibration of the vehicle body is input from the vehicle body floor to the cushion shell 32 through the support pad 40, the cushion shell 32 and the back shell 54 slide in the seat vertical direction with respect to the seat back frame 52. Is done.

That is, when the back shell 54 is moved to the upper side of the seat back frame 52 due to this vibration or the like, the front guide 74 (rack 84) and the rear guide 90 are moved together with the back shell 54 and the wire 100 (seat) as described above. The upper frame is slid (relatively moved) with respect to the back frame 52). As a result, the rack 84 of the front guide 74 and the pinion 108 of the coupling gear 102 cause the coupling gear 102 to rotate relative to the wire 100 in the direction of arrow B in FIG. 5, and the rolling surface 106 of the coupling gear 102 moves to the front. Roll on the front guide surface 82 of the guide 74.

Here, the wire 100 of the guide mechanism 70 is arranged close to the rear guide surface 94 side of the rear guide 90. Thereby, by making the cross section of the connection gear 102 into a fan shape, the ratio of the radius of the connection gear 102 (the radius of the rolling surface 106) to the radius of the wire 100 (the radius of the support hole 104) can be set large. Therefore, when the back shell 54 slides in the seat vertical direction with respect to the seat back frame 52, the connecting gear 102 is stably rotated around the axis of the wire 100, so that the back shell 54 with respect to the seat back frame 52 is Can be stabilized.

The wire 100 is in contact with the bead 96 of the rear guide 90. For this reason, it is possible to suppress the occurrence of backlash between the rear guide 90 and the wire 100 and between the front guide 74 and the connecting gear 102. That is, it is possible to suppress the backlash of the back shell 54 in the front-rear direction of the seat (front-rear direction).

In addition, the rear guide 90 is disposed on the rear side of the seat of the front guide 74, the rolling surface 106 of the connecting gear 102 is brought into contact with the front guide surface 82, and the wire 100 is brought into contact with the rear guide surface 94. For this reason, when the load from the seat occupant to the back shell 54 acts on the back shell 54 when the back shell 54 supports the back of the seat occupant, the guide member 72 (the front guide 74 and the rear guide 90) causes the wire 100 and the connecting gear to move. This load acts mainly between the front guide surface 82 and the connecting gear 102 because it tends to move rearward of the seat 102. That is, this load acts mainly between the front guide surface 82 and the rolling surface 106, and the connecting gear 102 performs a rolling motion with respect to the front guide surface 82. Therefore, this load is suppressed from acting between the wire 100 and the rear guide surface 94, and the sliding resistance between the wire 100 and the rear guide 90 when the back shell 54 slides with respect to the seat back frame 52 is suppressed. Can be reduced.

Furthermore, as described above, a rack 84 is formed on the front guide 74, and a pinion 108 that meshes with the rack 84 is formed on the connecting gear 102. Therefore, when the back shell 54 slides in the seat vertical direction with respect to the seat back frame 52, the connecting gear 102 is reliably rotated around the axis of the wire 100 by the rack 84 and the pinion 108, and the front guide Roll and move relative to the surface 82. Thereby, the sliding motion of the back shell 54 with respect to the seat back frame 52 can be further stabilized.

In particular, when a load on the front side of the seat acts on the back shell 54, the guide member 72 tends to move to the front side of the seat with respect to the wire 100 and the coupling gear 102. 94. That is, this load is suppressed from acting between the front guide surface 82 and the rolling surface 106, and the connecting gear 102 is not easily rotated relative to the wire 100. However, even in this case, the connecting gear 102 is reliably rotated around the axis of the wire 100 by the rack 84 and the pinion 108, so that the rotational shift of the connecting gear 102 with respect to the guide member 72 (the front guide 74 and the rear guide 90) is prevented. Can be suppressed.

Further, the bead 96 of the rear guide 90 is formed in a semicircular cross section, and the bead 96 and the wire 100 are in point contact. For this reason, the sliding resistance between the rear guide 90 and the wire 100 when the back shell 54 slides with respect to the seat back frame 52 can be further reduced.

Furthermore, non-interference concave portions 110 are formed on both end surfaces of the connecting gear 102 in the circumferential direction. When the back shell 54 is moved to the uppermost side of the seat, the rear guide 90 is disposed in one non-interference recess 110, and interference between the rear guide 90 and the connecting gear 102 is avoided. Further, when the back shell 54 is moved to the lowermost side of the seat, the rear guide 90 is disposed in the other non-interference recess 110, and interference between the rear guide 90 and the connecting gear 102 is avoided. Thereby, the radius of the connection gear 102 (rolling surface 106) can be set large corresponding to the movement stroke of the back shell 54 in the vertical direction of the seat.

Further, since the connecting gear 102 is formed in a sector column shape, the radius of the connecting gear 102 can be increased without increasing the distance between the front guide surface 82 and the rear guide surface 94.

Further, the rear guide 90 is formed with fitting holes 92 at both ends in the longitudinal direction, and the fitted portion 86 of the front guide 74 is fitted into the fitting hole 92. Thereby, after fixing the front guide 74 to the back shell 54, the wire 100 and the connecting gear 102 are arranged behind the seat of the front guide 74, and elastically extend the both longitudinal ends of the rear guide 90 in the seat vertical direction. The back shell 54 is connected to the seat back frame 52 by fitting the fitted portion 86 into the fitting hole 92 while being deformed. Therefore, the back shell 54 can be easily connected to the seat back frame 52.

In the present embodiment, the wire 100 is brought into contact with the rear guide surface 94 and the connecting gear 102 is configured to roll with respect to the front guide surface 82. Instead, the wire 100 may be brought into contact with the front guide surface 82 so that the connecting gear 102 rolls with respect to the rear guide surface 94.

In this embodiment, the rack 84 is formed on the front guide 74 and the pinion 108 is formed on the connecting gear 102. However, the rack 84 and the pinion 108 may be omitted.

Furthermore, in this embodiment, the bead 96 is formed on the rear guide surface 94 of the rear guide 90, but the bead 96 may be omitted.

Claims

A back shell that supports the back of the seated occupant and is slidable in the vertical direction of the seat back relative to the seat back frame;
A sliding operation of the back shell with respect to the seat back frame, which is provided on a back surface portion of the back shell, has a front guide surface and a rear guide surface that extend in the vertical direction of the seat back and is disposed to face the front and back of the seat back. A guide member for guiding
The seatback frame is coupled to the seatback frame and is disposed with the seat width direction as an axial direction, and is disposed between the front guide surface and the rear guide surface toward one side of the front guide surface and the rear guide surface, A shaft portion that is movable relative to the guide member in the vertical direction of the seat back;
A rotating body provided in the shaft portion so as to be relatively rotatable, and capable of rolling with respect to the other of the front guide surface and the rear guide surface;
Vehicle seat equipped with.
The vehicle seat according to claim 1, wherein the shaft portion is brought into contact with the rear guide surface, and the rotating body is allowed to roll with respect to the front guide surface.
A rack formed on the guide member and extending in the vertical direction of the seat back;
A pinion formed on the rotating body and meshed with the rack;
The vehicle seat according to claim 2, comprising:
The vehicle seat according to claim 2 or 3, wherein the rear guide surface and the shaft portion are in point contact.
The rotating body is formed in a fan-shaped column shape,
The vehicle seat according to any one of claims 2 to 4, wherein a non-interference portion that does not interfere with the guide member is formed on both circumferential end surfaces of the rotating body.
The guide member is
A front guide fixed to the back shell and formed with the front guide surface;
The rear guide surface is formed and a rear guide having a fitting portion to be fitted to the front guide;
The vehicle seat according to any one of claims 2 to 5, further comprising:
The vehicle seat according to any one of claims 1 to 6, wherein a pair of the guide member and the rotating body are provided in a seat width direction.