Location board in a covering member of automotive seat

A location board in a covering member of a vehicle seat, which is used in such a seat assemblage which involves bonding at least two cover sections of a covering member to a cushion member and is of such type that can be teared along the sewn jointed portion of those two cover sections for attaining a resultant seat. The location board is formed with a notched portion laying along an imaginary sewing line. In the seat assemblage, the two cover sections of covering member are sewn to one section of the location board, thus forming a series of sewing holes in the location board. The notched portion is elongated in reference to the sewing holes at such a length that permits a tearing to occur from the notched portion towards the sewing holes in a direction to prevent creation of a pointed projection at the teared edge of residual section of location board in the resultant seat at a stage of tearing off another section of the same location board.

BACKGROUND OF INVENTION 
1. Field of the Invention 
The present invention relates to a location board used in locating a 
covering member to a foam cushion member during assemblage of an 
automotive seat. 
2. Description of Prior Art 
The assemblage of an automotive seat entails bonding a covering member to 
the surface of a foam cushion member. There has been practiced the use of 
a location board for locating and retaining the covering member at a given 
position upon the foam cushion member, which is known, for example, from 
the Japanese Utility Model and Patent Laid-Open Pubs. Nos. 3-335995 and 
62-181086, and the U.S. patent appln. No. 686,157. A typical conventional 
seat assemblage using such location board is illustrated in FIGS. 1 
through 5. 
FIG. 1 schematically shows the assemlbing steps for bonding a covering 
member (1) to the outer surfaces of a cushion member (2) by means of an 
upper die (5), a lower die (4) and location board (30). 
As shown, the lower die (4) has a working surface formed in a shape 
generally conforming to the outer configuration of the foam cushion member 
(2), and that working surface of lower die (4) is provided with securing 
portions (4a). The covering member (1), which is to be secured upon this 
working surface of lower die (4), is formed such as to define therein a 
central seating cover section (11), peripheral cover sections (12)(12) 
sewn with the central seating cover section (11), and lateral cover 
section sections (13)(13). The peripheral cover sections (12)(12) are 
jointed at (1a) by sewing with the peripheral ends of central seating 
cover section (11) via a location board (3). The thus-formed cover member 
(1) is turned upside down and placed upon the lower die (4), with the sewn 
jointed portions (1a) of cover member (1) being secured in the securing 
portions (4a) of lower die (4). Hence, the cover member (1) exposes its 
reverse surface upon the lower die (4) for bonding with the foam cushion 
member (2). The cushion member (2) is formed such as to define therein a 
central seatting area (22) and a peripheral bolster areas (21)(21) 
surrounding the central seating area (22), each of those areas (22)(21) 
corresponding respectively to the central seating cover section (11) and 
peripheral cover sections (12). In the cushion member (2), there are 
formed recessed grooves (23)(23) at the respective junctures or boundaries 
between the central seating area (22) and peripheral bolster areas 
(21)(21). The flat bottom portion of the cushion member (2) is secured 
upon the upper die (5). Then, by lowering the upper die (5) towards the 
lower die (4), the outer surfaces of cushion member (2) are pressed 
against and bonded to the reverse surfaces of cover member (1). (of 
course, an adhesive has been applied to the outer surfaces of cushion 
member (2)) At this moment, both location boards (30) and sewn jointed 
portions of cover member (1) are inserted and bonded into the recessed 
grooves (23)(23). 
With a particular reference to the location boards (3) and sewn jointed 
portions (1a) mentioned above, it is seen from FIGS. 2, 3 and 4 that the 
location board (3) is so formed as to have, defined therein, a first half 
part (30), a second half part (31) and a boundary line (not shown) defined 
those first and second half parts (30)(31). Although not shown and as 
known in the art, such boundary line is made smaller in thickness than the 
other planar area, for a cutting purpose to be explained later. 
Designation (33) denotes a notched portion of generally "U" shape, which 
is formed at the forward edge (33b) of location board (3), defining a 
cutting introductory point from which the two half parts (30)(31) are cut 
apart from each other. The notched portion (33) extends a very short 
distance (L2)(for instance, not more than about 3 mm) from that forward 
edge (33b) of location board (3) toward the inward area of the same, as 
viewed from FIGS. 4 and 5. 
As shown in FIG. 4, one terminal end of the central seating cover section 
(11) and one terminal end of the peripheral cover section (12) are sewn 
together at the respective opposite sides of foregoing first half part 
(30) by two sewing threads (32)(34). In this respect, the FIG. 4 depicts 
the location board (3) to project from between the central and peripheral 
cover sections (11)(12), but as indicated by the hatching therein, those 
two cover sections (11) (12) are shown to be cut intentionally for the 
sake of highlighting the location board (3), and therefore it it to be 
understood that both cover sections (11) (12) expands their respective 
areas up to a line extending along the location board forward edge (33b). 
Designation (32a) in the location board stands for an imaginary sewing line 
along which the sewing thread (32) is sewn to the juxtaposed three layer 
of central cover section (11), first half part (30) of location board (3) 
and peripheral cover section (12), in a manner penetrating therethrough at 
a given interval (L1) (corresponding to a sewing pitch of sewing machine 
used; say, approx. 5 mm) that can be seen from a series of equidistant 
resultant sewing holes (32-1, 32-2 . . . ). As viewed from FIG. 4 and 5, 
those sewing holes are rowed, starting from the forward edge (33b); namely 
from the forward edges of three juxtpoased elements (3, 11, 12) and 
extending along the longitudinal direction of the imaginary sewing line 
(32a). It is noted here that the aforesaid notched portion (33) also 
extends along such longitudinal direction of sewing line (32a), whereupon, 
only at that particular notched portion (33), there are sewn directly 
together the two cover sections (11)(12) of covering member (1) as 
indicated by the first sewing hole (32-1). 
Designation (33a) denotes a pull portion defined at the forward end area of 
location board (3), which an operator pinches with his or her fingers and 
pulls upwardly in the arrow direction to start tearing the second half 
part (31) from the first half part (30) along the line of sewing holes 
(32-1, 32-2, . . . ). It is appreciated that the sewing holes (32-1, 32-2, 
. . . ) serves as a "tear off" perforated line to make easier the 
separation of the second half part (31) from the first one (30). 
Turning to the sewing state of those juxtaposed three layer of central 
cover section (11), location board (3) and peripheral cover section (12), 
it should be noted from FIGS. 2 and 4 that both central and peripheral 
cover sections (11)(12) are in the state of being turned upside down, 
exposing thus their respective reverse surfaces outwardly, not their 
frontal surfaces, which needs to be done as described earlier for seat 
assembling steps, and therefore as viewed from FIG. 4, the exposed surface 
of peripheral cover section (12) is the reverse side thereof, whereas 
likewise the oppositely disposed central cover section (11) exposes its 
reverse side to the other outward side. Thus, in FIG. 4, the frontal 
surfaces respectively of those two cover sections (11) face toward each 
other via the location board (3). 
In the practical assembling steps, the above-constructed cover member (1), 
as turned upside down, is placed upon the lower die (4), with the second 
half part (31) of location board (3) being inserted into the engagement 
groove (4a-1) formed in the securing portion (4a) of lower die (4), as 
best shown in FIG. 2. Thus, both first half part (30) of location board 
(3) and sewn jointed portion (1a) of cover member (1) erects upon the 
lower die (4). Then, when the upper die (5) is lowered towards the lower 
die (4), those location board first half (30) and cover member jointed 
portion (1a) are inserted into the recessed groove (23) of cushion member 
(2) mentioned above, as readily understandable from FIG. 2. As a result, 
the reverse surfaces of cover member (1) are bonded to the outer surfaces 
of cushion member (22), and then, a resultant seat is again turned upside 
down to attain a seat with the frontal surface of cover member (1) 
covering the whole outer surfaces of cushion member (2), which can be seen 
from FIG. 3. 
Since the location board first half (31) remains projected upon such 
resultant seat, an operator pinches with his or her fingers the pull 
portion (33a) of location board (3) and pulls it upwardly, as indicated by 
the arrow in FIG. 3, to tear the first half part (31) from the second one 
(30) which is bonded in the cushion member (2), along the sewing holes 
(32) in the location board (3). Consequently, the assembling of seat is 
completed. 
Although having described thus far the conventional seat assembling steps, 
it has yet been found as a problem that, as pointed out by designation 
(31a) in FIG. 3 as well as in FIG. 5, an undesired pointed projection 
remains uncut at the notched part (33) in the location board (3), when 
tearing off the first half part (31) of location board (3). This 
projection (31a) results in giving a hard objectionable touch or a pain to 
the hip of occupant sitting on the above-assembled conventional seat. 
To solve this problem, one can contemplate forming the notched part (33) in 
a straight line or in a "V" shape, but experiments thereon reveals that, 
with both of those alterations, the first half part (31)f of location 
board (3) is not cut off along the sewing holes (32a), but easily broken 
away from the body of location board (3) at a quite small area generally 
equal to the foregoing pull portion (33a) of the same location board (3). 
Therefore, the U-shaped notched pat (33) as illustrated is now thought to 
be a best mode of tearing or cuttig introductory means for starting to 
tear the location board first half (31) completely away from the mating 
second half (30) along the sewing holes (serving as the perforated holes). 
SUMMARY OF THE INVENTION 
As stated above, an objectionable pointed projection is created from the 
cut upper edge of the first half part of location board embeded in the 
cushion member when the second half part thereof is teared off from that 
first half part when pulling upwardly the pull portion of location board 
at a final statge of seat assemblage described above. A research was 
conducted by the inventor of the present invention as to the cause of this 
problem, and it is discovered that the notched portion of location board 
is very small in length (at L2) in reference to the series of sewing holes 
which are formed along the imaginary sewing line (32a), and this factor is 
attributable to the creation of such pointed projection. In other words, 
at the stage of sewing together both terminal portions respectively of 
those two covering member sections to the first half part of location 
board as explained above, a series of plural sewing holes are formed 
equidistantly a given distance therebetween, and the notched portion in 
question is much shorter than such given distance, according to the 
prior-art location board, with the result that, at the final stage of 
pulling up the pull portion of location board, an upward moment is 
produced from the upper longitudinal edge (at 33u) of the notched portion, 
causing a tear to proceed therefrom adjacent the U-shaped edge of the same 
downwardly towards the neighboring second sewing hole (at 32-2) in a 
sloped way. This tear creates the pointed projection in question. It is 
further noticed that, in most cases, the prior-art notched portion is 
merely of such a length that extends only over the first sewing hole (at 
32-1) towards the point adjacent the second sewing hole (32-2) and thus 
the foregoing first half part of location board is not retained well at 
that notched portion, which is additionally attributable to the creation 
of pointed projection. 
A purpose of the present invention is therefore to provide an improved 
location board which solves the above-noted problem. 
To achieve such purpose, a location board according to the present 
invention has, formed therein, an elongated notched portion which is made 
longer than the aforementioned given distance among the plural sewing 
holes. 
Accordingly, such elongation of notched portion widens the pull portion of 
location board and extends further the spacing of notched portion along 
the sewing line, thereby causing the above-discussed upward moment to be 
produced from the lower longitudinal edge (at 33dw) in contrast to that of 
the prior-art location board, so that, according to the present invention, 
when pulling up the pull portion of location board, a tear proceeds from 
that lower longitudinal edge adjacent the U-shaped edge, of notched 
portion, upwardly towards the neighboring third sewing hole (at 32-3). 
Therefore, there is never formed such pointed projection at the final 
stage of tearing off the second half part of location board from the first 
one in the seat assemblage. Preferably, the notched portion may be 
elongated at such a length that allows two sewing bridges (at 32-1 and 
32-2) of sewing thread (32) to be present in the spacing thereof, so as to 
firmly retain the portion of the first half part of location board which 
lies at that notched portion, thereby helping the upward moment to easily 
work from a line corresponding to the lower longitudinal edge (33dw) of 
notched portion.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION 
At first, it should be understood that the present invention is directed to 
an improvement based on the previously described prior-art location board 
(3) and other all associated elements of seat, that all like designations 
in the prior art description above correspond to all like designations to 
be given hereinafater, and that any specific explanation on the common 
parts and elements between the present invention and prior art is omitted 
for the sake of simplicity. 
We, the inventors, researched the causes of the above-stated problem with 
the prior-art location board (3), and find that the extremely small 
formation of notched part (33) is a cause leading to the creation of 
above-noted undesired pointed projection (31a). Namely, referring to FIG. 
5, according to the prior-art location board (3), the notched part (33) 
extends at such small distance (L2) from the forward edge of location 
board (3) into the body of same. The small distance (L2) is even smaller 
than a distance (L1) (corresponding to the sewing pitch of sewing machine 
used, which is not shown though, and about 5 mm as mentioned previously) 
between the first sewing hole (32-1) and second one (32-2) along the 
imaginary sewing line (32a). With this conventional design of location 
board (3), it has been found that when pulling up the pull portion (33a) 
of location board (3), a tearing proceeds from the U-shaped end of notched 
part (33) in a downwardly inclined direction, as indicated by the two-dot 
chain line under designation (32b) in FIG. 5, towards the second hole 
(32-2). The reason behind this tearing manner could be that an upward 
moment of a pulling force (as indicated by the two-dot-chain-line arrow in 
FIG. 5) is produced from a line corresponding to the upper longitudinal 
edge (33u) of notched part (33) by the reason that (i) the prior-art 
notched part (33) is of such very small length (L2) and (ii), as can be 
seen from the first sewing hole (32-1), the sewing thread (32) penetrates 
only one time, or presents only one sewing bridge through the jaxtaposed 
layer of central and peripheral cover sections (11)(12) of covering member 
(1) within the spacing of notched part (33). Hence, the upward moment 
works in relation to the adjacent second hole (32-2), thereby orienting 
the pulling force in the downwardly inclined direction from the notched 
part (33) to the second hole (32-2), which causes a tear between the 
U-shaped end of notched part (33) and second hole (32-2) in the same 
downwardly inclined direction, as indicated by the corresponding two-dot 
chain line in FIG. 5. Thereafter, the first half part (31) of location 
board is cut continuously apart from the second one (30) along the 
imaginary sewing line (32a). As a result thereof, the pointed projection 
(31a) in question is created at the region between the notched part (33) 
and second hole (32-2), raising the problem of giving an objectionable 
hard touch or pair to the hip portion of an occupant on the resultant 
seat. 
Now, reference is made to FIG. 6, which shows an emodiment of location 
board (3A) in accordance with the present invention. The location board 
(3A) is basically identical to the above-stated prior art one (3), only 
except that there is formed a longer notched part (33A) in the board (3A) 
at such a greater distance (L3) than that (L2) in the prior-art notched 
part (33). Specifically stated, that particular notched part (33A) extends 
from the first sewing hole (32-1) and passes the second sewing hole 
(32-2), approximating its length to a point close to a third sewing hole 
(32-3) in the sewing line (32a); namely, at the distance (L3) which is 
larger than the distance (L1) between those first and second holes 
(32-1)(32-2) and smaller than the doubled distance (L1+L1) between the 
first and third holes (32-1)(32-3). Preferably, the distance or length 
(L3) of foregoing notched part (33A) may be approx. 6 mm. (The height-wise 
width of the notched part (33A) is approx. 2 mm, for instance) By being so 
designed, when pulling up the pull portion (33a) of location board (3A) in 
the arrow direction in FIG. 6, a tearing proceeds from the U- shaped end 
of notched part (33A) in an upwardly inclined direction towards the 
adjacent third hole (32-3) as indicated by the two-dot chain line at (32b) 
in FIG. 6. Therefore, with this novel arrangement of location board (33A), 
a seat assembling is carried out in the same way and steps with those of 
the previously described conventional seat assemblage, and then, in the 
resulting seat, there is never formed such pointed projection (31a) found 
in the prior-art board (3) since the tearing starts in a direction 
reversal to that of the prior-art location board (3), leaving thus a 
teared edge which slopes downwardly to a level of lower longitudinal edge 
(33dw) of notched part (33A) embedded in the recessed groove (23) of 
cushion member (2), as viewed from FIG. 6 in conjunction with FIG. 3. 
From the above discovery, it can be noticed that such elongation of notched 
part (33) as in the one (33A) serves to not only make longer the pull 
portion (33a), but also allow the sewing thread (32) to provide two sewing 
bridges (at (32-1) and (32-2)) within the spacing of the notched part 
(33A). Those two factors are an effective contributor to producing an 
upward moment from a line corresponding to the lower longitudinal edge 
(33dw) of notched part (33A) in contrast to the upward moment in the 
prior-art location board (3) which is produced from the upper edge (33u) 
of notched part (33). Namely, it is thought theoretically that the widened 
pull portion (33a) helps to disperse the pulling force so as to transfer 
the base point of the upward moment towards the line corresponding to the 
lower longitudinal edge (33dw) of notched part (33A), and that such two 
sewing bridges at (32-1)(32-2), which pass transversely through the 
spacing of notched part (33A), serve to firmly retain a part of the first 
location board half (30A) which lies at the notched part (33A) and thus 
spaced apart from the second location board half (31A), thereby causing 
production of upward moment from that lower edge (33dw ) of notched part 
(33A) on the side of first location board half (30A). Therefore, the 
pulling force exerted on the location board (3A) is oriented in the 
upwardly inclined direction from the U-shaped end of notched part (33A) to 
the third sewing hole (32-3), as viewed from FIG. 6, so that a tear is 
created in the same upwardly inclined direction as indicated by the 
corresponding two-dot chain line (32a) in FIG. 6, to extend between the 
U-shaped end of notched part (33A) to the third sewing hole (32-3). 
Thereafter, the second location board half (31A) may be continuously cut 
apart from the first one (30A). 
The location board (3A) is preferably made of a synthetic resin material 
having a somewhat elastic property.