JP4528110B2 - Vehicle seat back - Google Patents

Description

  The present invention relates to an improvement in a vehicle seat back.

A conventional vehicle seat back includes, for example, a seat back frame and a pad made of urethane foam disposed on the front side of the seat back frame as disclosed in Patent Document 1. A plurality of S-shaped springs are spanned between the left and right side frame portions of the seat back frame. When a load from the occupant is applied to the seat back, the load is received by the S-shaped spring through the pad.
JP 2004-66931 A

  However, in the above conventional structure, when the load from the occupant is large, the S-shaped spring is greatly bent backward, so the thickness of the seat back is determined in consideration of the bending allowance. There was a drawback that the length was large.

  The present invention has been made to solve the above-described problems. In a vehicle seat back including a seat back frame and an elastic front pad disposed on the front side of the seat back frame, the seat back frame includes: The gist is that a rear pad that is elastic and harder than the front pad is provided on the rear side, and the front pad and the rear pad face each other. According to the above configuration, when the load from the rear of the occupant is large, the load is received by the rear pad via the front pad. Since the S-shaped spring as in the conventional seat back is not provided, the thickness of the seat back can be reduced. Since the rear pad has elasticity, it does not put a heavy burden on the passenger. In addition, since the rear pad is harder than the front pad, it is possible to ensure shape retention and enhance load bearing ability.

  Preferably, a gap is formed between regions of the front pad and the rear pad that receive a load from an occupant. As a result, the load from the occupant can be received only by the front pad at normal times, and comfort can be given to the occupant.

  Preferably, substantially the entire peripheral edge portions of the front pad and the rear pad are in contact with each other, and the seat back frame is disposed inside thereof. According to this, the exposure of the seat back frame can be eliminated, and the work of assembling the front pad and the rear pad into the seat back frame can be simplified.

  Preferably, the rear pad is made of a foam molded product of polypropylene beads, and the expansion ratio of the polypropylene beads is 15 to 30 times. Since the expansion ratio is 15 times or more, it is possible to obtain a degree of elasticity that does not cause pain to the passenger, and because the expansion ratio is 30 times or less, it is possible to ensure shape retention and load bearing capacity.

  Preferably, the front pad has a front surface covered with a cover, and the cover wraps around the upper edge and the left and right edges of the front pad and the rear pad to form a fixing groove formed on the back surface of the rear pad. Inserted and fixed. As a result, the terminal processing of the cover can be easily performed.

  As described above, according to the present invention, the seat back can be configured simply and inexpensively, and the thickness can be reduced.

  Hereinafter, a vehicle seat back according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the seat back 1 includes a seat back frame 10 (hereinafter simply referred to as a frame), a front pad 20 disposed on the front side of the frame 10, and a rear side disposed on the rear side of the frame 10. A pad 30, a cover 40 (shown only in FIGS. 4 and 5), and a tray 50 (reinforcing plate) are provided.

  As shown in FIGS. 1 and 2, the frame 10 is composed of left and right side frame parts 11 having an upright and slender plate shape and inverted U-shaped pipes, and both legs are at the upper ends of the left and right side frame parts 11. It has a fixed upper frame portion 12 and a lower frame portion 13 which is formed of a pipe extending straight and horizontally and is spanned between the lower end portions of the left and right side frame portions 11.

The lower end portion of the side frame 11 is connected to a seat cushion (not shown) via a hinge mechanism, whereby the angle of the seat back 1 can be adjusted.
A pair of cylindrical supports 14 for inserting and supporting a stay of a headrest (not shown) are fixed to the horizontal portion of the upper frame portion 12 separately on the left and right.

  The front pad 20 is a molded product of a single polyurethane foam, and has a wide central area 21 (substantially corresponding to the area inside the left and right side frame portions 11) that receives a load from the occupant A (shown only in FIG. 5). And an upper edge 22, a lower edge 23, and left and right edges 24. The upper edge portion 22 and the left and right edge portions 24 protrude forward from the load receiving area 21.

The rear pad 30 is made of a single polypropylene bead foam molded product (resin foam molded product). The expansion ratio of the polypropylene beads is 15 to 30 times, and 25 times in this embodiment. The rear pad 30 has elasticity, but is much harder than the front pad 20 made of polyurethane foam. When the expansion ratio is 15 times, the compression hardness is 2.6 kg / cm ² according to the measurement method according to JIS K 6767, and the hardness is about 41 times that of the front pad 20. When the expansion ratio is 30 times, the compression hardness is 1.3 kg / cm ^2, which is about 21 times that of the front pad 20.

  Similar to the front pad 20, the rear pad 30 has a wide center load receiving region 31 (which substantially corresponds to a region inside the left and right side frame portions 11), an upper edge portion 32, a lower edge portion 33, and left and right edges. Part 34 is provided. As best shown in FIG. 4, the front surface of the load receiving region 31 is a curved concave surface in accordance with the back shape of the occupant. The back surface of the load receiving area of the front pad 20 and the front surface of the load receiving area 31 of the rear pad 30 face each other through the gap 60. In the gap 60, other components such as an elastic member such as an S-shaped spring are not arranged.

  As shown in FIG. 2, a recess 35 is formed in the front surface between the load receiving region 31 and the upper edge portion 32 of the rear pad 30. The lower end of the headrest stay enters the recess 35.

  As shown in FIGS. 1 and 4, the back surface of the peripheral portion (that is, the upper edge portion 22, the lower edge portion 23, and the left and right edge portions 24) of the front pad 20 and the peripheral portion (that is, the upper edge portion 32) of the rear pad 30. , The lower edge portion 33 and the front surface of the left and right edge portions 34) are in contact with each other. The frame 10 is disposed on the inner side of the peripheral edge where the pads 20 and 30 are in contact.

  As shown in FIG. 4, receiving grooves 24a and 34a are formed along and adjacent to the left and right edges 24 and 34 on the opposing surfaces of the pads 20 and 30, respectively. A frame portion 11 is accommodated.

  As shown in FIGS. 1 and 2, a pair of semicircular recesses 22a and 32a are formed on the upper edges 22 and 32 of the pads 20 and 30, respectively. The upper end of the support 14 is fitted.

  As shown in FIGS. 1 to 3, the left and right ends of the lower edge portions 23, 33 of the pads 20, 30 are recessed portions 23a, 33a, and a hinge mechanism is disposed in these recessed portions 23a, 33a. It is like that.

  The opposing surfaces of the lower edges 23 and 33 of the pads 20 and 30 are formed with semi-circular recesses 23b and 33b extending linearly in the left-right direction along the lower edges 23 and 33. The hinge shaft of the hinge mechanism is fitted in the recesses 23b and 33b.

  As shown in FIG. 1, the peripheral portions of the pads 20 and 30 are locally separated in the vicinity of the left and right ends of the lower edge portions 23 and 33, thereby forming a small opening 61. The side frame portion 11 and the hinge mechanism are connected by a bracket (not shown) passing through the opening 61.

  As shown in FIGS. 3 and 4, a shallow recess 36 having a vertically long rectangle is formed over a wide area on the back surface of the rear pad 30, and a fixing groove 37 is formed on the upper edge and the left and right edges of the recess 36. Is formed.

  The cover 40 covers the front surface of the front pad 20, wraps around the upper edge portions 22 and 32 and the left and right edge portions 24 and 34 of the pads 20 and 30, and reaches the back surface of the rear pad 30. The ends of the upper and left and right edges of the cover 40 are fixed by being press-fitted into the fixing groove 37 of the rear pad 30 together with a press-fitting member 70 having a bar shape with a rectangular cross section.

  The tray 50 is disposed so as to cover the entire area of the recess 36 of the rear pad 30. In the present embodiment, the tray 50 is formed with a clip portion 51, and the tray 50 is fixed to the rear pad 30 by pressing the clip portion 51 into a hole formed on the back surface of the rear pad 30. Yes. The tray 50 serves to reinforce the rear pad 30 and hide the terminal fixing portion of the cover 40.

In the above configuration, when the load from the occupant A is small, the load is received only by the front pad 20. When the load increases, the load receiving area 21 of the front pad 20 bends backward, and the gap 60 is reduced.
As described above, in the normal use state, the load from the occupant A is mainly borne by the front pad 30 and does not depend on the rear pad 30, so that the occupant feels the hardness of the rear pad 30. Absent. In particular, in the present embodiment, a gap 60 is formed between the front pad 20 and the rear pad 30, and there is a load region that is borne only by the front pad 20, so that a better riding comfort can be obtained.

  When a larger load is applied to the front pad 20, the gap 60 disappears, the load receiving area 21 of the front pad 20 hits the load receiving area 31 of the rear pad 30, and the load is received by the rear pad 30. Since the load receiving region 31 has a concave curved surface, the occupant's retainability is good.

Since the rear pad 30 has elasticity, the occupant does not feel pain. In particular, this performance can be ensured by setting the foaming ratio of the rear pad 30 to 15 times or more.
Since the rear side pad 30 is harder than the front side pad 20, while being able to ensure shape retention property, it can bear a big load. In particular, this performance can be ensured by setting the expansion ratio of the rear pad 30 to 30 times or less.

  The seat back 1 is not equipped with an S-shaped spring for receiving the load, and the load is borne by the front and rear pads 20 and 30, so that the bending allowance of the S-shaped spring is not required, and the thickness can be reduced. It is.

  The present invention is not limited to the above embodiment, and various aspects can be adopted. For example, the lower edge portions of the front and rear pads do not have to be in contact with each other. The material of the front and rear pads is not limited to the above embodiment, and various materials can be selected.

It is a side view which shows the seat back concerning this invention, omitting a cover and a hinge mechanism. It is a perspective view which shows the flame | frame and rear pad of the seat back. It is a rear view of the back side pad. It is an expansion cross-sectional view of the left half of the seat back. FIG. 5 is a view corresponding to FIG. 4 showing a state when a large load from the passenger is applied to the seat back.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Seat back 10 Frame 20 Front side pad 21 Load receiving area 22 Upper edge part 23 Lower edge part 24 Left and right edge part 30 Rear side pad 31 Load receiving area 32 Upper edge part 33 Lower edge part 34 Right and left edge part 37 Fixing groove 40 Cover 60 Void

Claims (3)

In a vehicle seat back including a seat back frame and an elastic front pad disposed on the front side of the seat back frame,
On the rear side of the seat back frame, a rear pad having elasticity and harder than the front pad is provided, and the front pad and the rear pad are opposed to each other,
A gap is formed between regions receiving the load from the occupant in the front pad and the rear pad,
A vehicular seat back characterized in that substantially all the peripheral edges of the front pad and the rear pad are in contact with each other, and the seat back frame is disposed inside thereof . 2. The vehicle seat back according to claim 1 , wherein the rear pad is made of a foam molded product of polypropylene beads, and the foaming ratio of the polypropylene beads is 15 to 30 times. On the back surface of the rear pad, a shallow concave portion having a vertically long rectangle is formed over a wide area, and fixing grooves are formed on the upper edge portion and the left and right edge portions of the concave portion,
Said front pad is covered with the front by the cover, the cover is crowded around the upper edge and the left and right edges of the front pad and the rear pad, fixedly inserted into the fixing groove,
The auxiliary plate according to claim 1 or 2 , further comprising an auxiliary plate, the auxiliary plate being accommodated in the concave portion of the rear pad so as to occupy the entire area thereof, and being fixed to the rear pad . Vehicle seat back.

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