Removable expanding fastener

Disclosed here is a fastener made of synthetic resin or the like for removably fixing a plurality of plate-like members, said fastener comprising a female member and a male member, said female member comprising a base plate formed with a hole into which a shaft portion of said male member is inserted, a stopper of substantially W-shape in section provided with a pair of leg portions extending from a lower surface of said base plate along an edge portion of said hole and a link portion of substantially inversed U-shape in section for connecting said leg portions, and a pair of engagement projections inwardly projecting from an inner periphery of said hole; said male member comprising a head portion, a shaft portion provided with a neck portion downwardly extending from said head portion and a flat portion downwardly extending from said neck portion and adapted to be inserted into said hole, said flat portion being provided with a pair of stop projections and shoulders adapted to be engaged with said engagement projections at an upper portion thereof, said flat portion being formed with a hollow portion opened at a lower end thereof to thereby form a substantially sectionally rectangular cylindrical shape, wherein said link portion of said stopper is rotatably fitted in said hollow portion, and said leg portions and said link portion are elastically deformed to be spread and contracted in interlocking relation with each other.

BACKGROUND OF THE INVENTION 
The present invention relates to a fastener for removably fixing a 
plurality of plate-like members. 
A conventional fastener of this type is described in Japanese Patent 
Publication No. 55-45765. As shown in FIGS. 27 to 29, the conventional 
fastener 101 is designed to detachably secure a pair of plate-like members 
113 and 114 having mating perforations. The fastener 101 comprises a 
grommet 102 including a head 103 having an opening 104 therethrough and a 
pair of spreadable essentially parallel stems 105 extending axially from 
opposite sides of the opening for insertion through the mating 
perforations, a head 107 and a shank 108. The shank 108 is provided with 
cam surfaces 109 mutually engageable with the stems 105 of the grommet 102 
on the sides thereof. The shank 108 forms a bolt 106 designed to spread 
the pair of stems 105 of the grommet 102. The stems 105 of the grommet 102 
are provided with a pair of laterally offset yieldable fingers extending 
inwardly therefrom. The shank 108 is formed with an annular groove 111 
engageable with the fingers 110 so as to prevent retraction of the bolt 
106 from the grommet 102 once the bolt 106 has been inserted therein. The 
extremity of the shank 108 is initially connected to the head 103 of the 
grommet 102 by frangible connecting webs 112. 
According to the structure of the conventional fastener as aforementioned, 
after the bolt 106 is inserted into the grommet 102, and the stems 105 of 
the grommet 102 are creeped under a spread condition after a long time, 
the stems 105 are not returned to their original condition irrespective of 
rotation of the bolt 106. Accordingly, insertion of the grommet into the 
mating perforations of the plate-like members 113 and 114 is rendered 
difficult to cause reduction in working efficiency. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide a fastener having leg 
portions of the female member which may be returned to their original 
position even when the leg portions have been creeped to be outwardly 
spread. 
According to one aspect of the present invention, there is provided a 
fastener made of synthetic resin or the like for removably fixing a 
plurality of plate-like members, said fastener comprising a female member 
and a male member, said female member comprising a base plate formed with 
a hole into which a shaft portion of said male member is inserted, a 
stopper of substantially W-shape in section provided with a pair of leg 
portions extending from a lower surface of said base plate along an edge 
portion of said hole and a link portion of substantially inversed U-shape 
in section for connecting said leg portions, and a pair of engagement 
projections inwardly projecting from an inner periphery of said hole; said 
male member comprising a head portion, a shaft portion provided with a 
neck portion downwardly extending from said head portion and a flat 
portion downwardly extending from said neck portion and adapted to be 
inserted into said hole, said flat portion being provided with a pair of 
stop projections and shoulders adapted to be engaged with said engagement 
projections at an upper portion thereof, said flat portion being formed 
with a hollow portion opened at a lower end thereof to thereby form a 
substantially sectionally rectangular cylindrical shape, wherein said link 
portion of said stopper is rotatably fitted in said hollow portion, and 
said leg portions and said link portion are elastically deformed to be 
spread and contracted in interlocking relation with each other. 
With this arrangement, even if the leg portions are creeped under the 
spread condition after a long time is elasped under such a condition where 
the female member and the male member are lockingly engaged with each 
other to fix the plate-like members, the leg portions may be forcibly 
returned to their original condition by rotating the male member at 90 
degrees and forcibly contracting the link portion as spread with the aid 
of the flat portion. Accordingly, in using the fastener again, the 
fastener may be easily inserted into the mount holes without any 
inconvenience, and the plate-like members may be securely fixed to each 
other. Further, as the female member and the male member are used as an 
assembly after both the members are engaged with each other, handling of 
parts may be made easy. 
According to another aspect of the present invention, there is provided a 
fastener made of synthetic resin or the like for removably fixing a 
plurality of plate-like members, said fastener comprising a female member 
and a male member, said female member comprising a base plate formed with 
a hole into which a shaft portion of said male member is inserted, a pair 
of opposed stoppers of substantially W-shape in section provided with a 
pair of leg portions extending from a lower surface of said base plate 
along an edge portion of said hole and a pair of engagement portions 
upwardly extending from lower ends of said leg portions and arranged in 
opposed relation with each other, and a pair of engagement projections 
inwardly projecting from an inner periphery of said hole; said male member 
comprising a head portion, a shaft portion provided with a neck portion 
downwardly extending from said head portion and a flat portion downwardly 
extending from said neck portion and adapted to be inserted into said 
hole, said flat portion being provided with a pair of stop projections and 
shoulders adapted to be engaged with said engagement projections at an 
upper portion thereof, said flat portion being formed with a hollow 
portion opened at a lower end thereof to thereby form a substantially 
sectionally rectangular cylindrical shape, wherein said engagement 
portions of said stopper are rotatably fitted in said hollow portion, and 
said leg portions and said engagement portions are elastically deformed to 
be spread and contracted in interlocking relation with each other. 
With this arrangement, even if the leg portions are creeped under the 
spread condition after a long time is elasped under such a condition where 
the female member and the male member are lockingly engaged with each 
other to fix the plate-like members, the leg portions may be forcibly 
returned to their original condition by rotating the male member at 90 
degrees and forcibly contracting the link portion as spread with the aid 
of the flat portion. Accordingly, in using the fastener again, the 
fastener may be easily inserted into the mount holes without any 
inconvenience, and the plate-like members may be securely fixed to each 
other. Further, both the engagement portions may be arranged more nearly 
to reduce a predetermined width, so as to reduce a dimension of associated 
parts and thereby make a size of the fastener. The diameter of the mount 
holes of the plate-like members may be also reduced to secure a strength 
of the plate-like members. Further, as the female member and the male 
member are used as an assembly after both the members are engaged with 
each other, handling of parts may be made easy. 
The invention will be more fully understood from the following detailed 
description and appended claims when taken with the drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to FIGS. 1 to 8 showing a first preferred embodiment, reference 
numeral 1 generally designates a fastener for fixing plate-like members 29 
and 30. The fastener 1 is composed of a female member 2 and a male member 
19. 
Reference numeral 3 designates a base plate of the female member 2 which 
plate is substantially flatly formed. The base plate 3 is formed with an 
elongated recess 4 having an insertion hole 5 for permitting insertion of 
the male member 19. There is formed at a lower peripheral edge of the 
insertion hole 5 a stopper 6 of substantially W-shape in section, and 
there are formed at the peripheral edge perpendicular to the stopper 6 
guides 15 adapted to come into contact with a peripheral edge of mount 
holes 31 and 32 of the plate-like members 29 and 30. The stopper 6 and the 
guides 15 are adapted to be inserted into the mount holes 31 and 32. 
The stopper 6 is formed with leg portions 7 downwardly extending along the 
peripheral edge of the insertion hole 5 corresponding to an arcuate edge 
of the recess 4 and with a link portion 14 of inversed U-shape. The leg 
portions 7 are arcuate with a predetermined thickness at its base. The leg 
portions 7 are formed with outer arcuate surfaces 8 having the same arc 
extending near to its lower portion, and with slant surfaces 9 inclined to 
an axis side of the insert hole 5 at the lower portion. The leg portions 7 
are further formed with inner arcuate surfaces 10 having slant surfaces 11 
downwardly inclined near from its base to the axis side of the insert hole 
5 and also having vertical surfaces 12 at its lower end portion. 
Thin-walled portions 13 are oppositely formed at the lower ends of the leg 
potions 7. The link portion 14 is formed in substantially semi-circular 
and inversed U-shape in section between both the thin-walled portions 13. 
That is, the leg portions 7 are integrally connected through the 
thin-walled portions 13 with the link portion 14 to thereby form the 
stopper 6 of substantially W-shape in section. The leg portions 7 are 
elastically deformable so as to be spread about the base portion thereof, 
and the link portion 14 is adapted to be spread about its top in 
cooperation with the elastic deformation of the leg portions 7. Under a 
normal or unspread condition, a width of the U-shape of the link portion 
14 is set to a predetermined value h1. 
The arcuate guides 15 are formed in a tongue-like shape as viewed in 
section with a predetermined thickness as extending from the peripheral 
edge of the insert hole 5 perpendicular to the stopper 6, and are adapted 
to come into contact with the peripheral edge of the mount holes 31 and 32 
of the plate-like members 29 and 30. There are formed on the peripheral 
edge of the insertion hole 5 and the inside surface of the guides 15 
engagement projections 16 having horizontal upper guide surfaces 17 and 
slanted lower guide surfaces 18. The existence of the engagement 
projections 16 makes the insert hole 5 substantially rectangular with an 
arcuate portion. 
The male member 19 includes a substantially planar head portion 20 and a 
shaft portion 21 having a flat portion 23 adapted to be inserted into the 
insert hole 5 of the female member 2. 
The shaft portion 21 is formed with a neck portion 22 having a 
predetermined diameter, that is, a diameter (d) allowed to be inserted 
between both the engagement projections 16, and a predetermined length at 
a substantially central position of the head portion 20. The flat portion 
23 is integrally formed with the neck portion 22 in such a manner as to 
downwardly extend therefrom. The flat portion 23 has a width W allowed to 
be inserted into the insert hole 5 and a thickness T equal to the diameter 
(d) of the neck portion 22. Opposite outer surfaces of the flat portion 23 
in the direction of the thickness T is formed arcuately. The flat portion 
23 is further formed with a hollow portion 24 having a lower opening of 
substantially rectangular in section. A width of the lower opening of the 
hollow portion 24 in the direction of the width W is set to W1 permitting 
expansion of the link portion 14 of the female member 2, while a width in 
the direction of the thickness T is set to T1 permitting insertion of the 
link portion 14 having the width h1 under the normal condition. The hollow 
portion 24 extends to the neck portion 22. The flat portion 23 is formed 
at its upper part with shoulder portions 25 inclined at a predetermined 
angle from a junction of the neck portion 22 in the direction of the width 
W. The shoulder portions 25 are adapted to engage with the lower guide 
surfaces 18 formed at the engagement projections 16 of the female member 
2. The flat portion 23 is further formed at the junction of the neck 
portion 22 at the center in the direction of the width W with stop 
projections 26 adapted to engage with the upper guide surfaces 17 formed 
at the engagement projections 16 of the female member 2. The stop 
projections 26 are formed with slits 27 on both sides thereof, and are 
allowed to be elastically deformed. Reference numeral 28 designates a 
handle provided on the upper surface of the head portion 20. 
In operation, when the stopper 6 of the female member 
inserted into the mount holes 31 and 32 of the plate-like members 29 and 30 
as registered, the base portions of the outer arcuate surfaces 8 of the 
leg portions 7 and the outer arcuate surfaces of the guides 15 are brought 
into contact with the edges of the mount holes 31 and 32. Thereafter, when 
the flat portion 23 of the male member 19 is inserted into the insert hole 
5, both the side surfaces of the flat portion 23 in the direction of the 
thickness T are brought into contact with the vertical surfaces 12 of the 
inner arcuate surfaces 10 of the leg portions 7, and the link portion 14 
is inserted into the hollow portion 24 of the flat portion 23. As the 
width W of the flat portion 23 is greater than the distance between both 
the vertical surfaces 12 of the leg portions 7, both the leg portions 7 
are elastically deformed by the flat portion 23 to be outwardly spread, 
and simultaneously the link portion 14 connected to the leg portions 7 is 
elastically deformed in the hollow portion 24 to be outwardly spread about 
its top. With further insertion of the flat portion 23, the stop 
projections 26 are brought into contact with the upper projected portions 
of the engagement projections 16, and is elastically deformed to the 
hollow portion 24 side. Then, the stop projections 26 pass through the 
upper projected portions of the engagement projections 16, and 
simultaneously they are elastically returned to its original condition to 
be engaged with the upper guide surfaces 17 of the engagement projections 
16. Thus, the leg portions 7 of the female member 2 are outwardly spread 
below the mount holes 31 and 32 by the flat portion 23 of the male member 
19, and the stop projections 26 of the male member 19 are lockingly 
engaged with the engagement projections 16 of the female member 2 to 
intensively fix the plate-like members 29 and 30. 
In the case that the fixed condition of the plate-like members 29 and 30 is 
intended to be released, the handle 28 provided at the head portion 20 of 
the male member 19 is rotated at 90 degrees to rotate the flat portion 23 
of the shaft portion 21 at 90 degrees about the neck portion 22 and 
thereby release the spread condition of the leg portions 7. Then, the stop 
projections 26 of the flat portion 23 is slided to be disengaged from the 
upper guide surfaces 17. At the same time, the link portion 14 in the 
hollow portion 14 under the spread condition is forcibly contracted by the 
sides of the flat portion 23 in the direction of the width W, and the leg 
portions 7 are also forcibly returned to their original condition. As a 
result, the distance between both the leg portions 7 is slightly smaller 
than the diameter of the mount holes 31 and 32, and the shoulder portions 
25 of the flat portion 23 are engaged with the lower guide surfaces 18 of 
the engagement projections 16 of the female member 2. Then, the handle 28 
is upwardly drawn to remove the male member 19 and the female member 2 as 
integrally fixed to each other and thereby release the fixed condition of 
the plate-like members 29 and 30. 
In the case that the fastener 1 is intended to be fixed to the plate-like 
members 29 and 30, the fastener 1 is inserted into the mount holes 31 and 
32, and the handle 29 is rotated at 90 degrees to rotate the flat portion 
23. As a result, the leg portions 7 are elastically deformed to be 
outwardly spread, and the stop projections 26 are engaged with the upper 
guide surfaces 17 to thereby fix the plate-like members 29 and 30. 
According to the fastener of the preferred embodiment, even if the leg 
portions 7 are creeped under the spread condition after a long time is 
elasped under such a condition where the female member 2 and the male 
member 19 are lockingly engaged with each other to fix the plate-like 
members 29 and 30, the leg portions 7 may be forcibly returned to their 
original condition by rotating the male member 19 at 90 degrees and 
forcibly contracting the link portion 14 as spread with the aid of the 
flat portion 23. Accordingly, in using the fastener again, the fastener 
may be easily inserted into the mount holes 31 and 32 without any 
inconvenience, and the plate-like members 29 and 30 may be securely fixed 
to each other. Further, as the female member 2 and the male member 19 are 
used as an assembly after both the members are once engaged with each 
other, handling of parts may be made easy. 
Referring next to FIGS. 9 to 17 showing a second preferred embodiment, a 
space 35 defined between a body 33 and a trim 34 is utilized as a storing 
space for example, and the fastener 1 is utilized for a lid 36 for closing 
an opening W opened through the trim 34, the lid 36 including a female 
member 37 and a male member 44 as integrally formed. 
The female member 37 is integrally formed with a bottom portion 39 
(corresponding to the base plate 3 in the first preferred embodiment) of a 
recess 38 formed at the lid 36, the recess 38 having a predetermined 
diameter and a predetermined depth. The bottom portion 39 is formed with 
an insertion hole 5 at the center thereof to form a stopper 6, guides 15 
and engagement projections 16 in the same manner as in the first preferred 
embodiment. The bottom portion 39 is formed with a trapezoidal projection 
40 on the upper side thereof, which projection has a predetermined radius 
from the center of the insert hole 5 and a predetermined height. The 
trapezoidal projection 40 is formed at its outer circumference with 
stoppers 42 and projections 43 to provide locking recesses 41 at right 
angles to each other, so as to restrict rotation of the male member 44. A 
head portion 45 of the male member 44 is inertable into the recess 38, and 
the handle 28 has a height such that it is almost sunk in the recess 38. 
The head portion 45 is formed with a shaft portion 21 including a neck 
portion 22 and a flat portion 23 at the center of the lower surface 
thereof in the same manner as in the first preferred embodiment. The head 
portion 45 is formed with projecting edges 46 having a height almost equal 
to that of the trapezoidal projection 40 at a lower surface edge thereof. 
The projecting edges 46 are formed with opposite locking projections 47 
adapted to engage with the locking recesses 41 at an angular position of 
45 degrees from the center in the direction of the shorter side of the 
flat portion 23 in such a manner as to inwardly project toward the center 
of the shaft portion 21. When the male member 44 and the female member 37 
are engaged with each other in the same manner as in the first preferred 
embodiment, rotation of one of the locking projections 47 is restricted to 
90 degrees by one of the stoppers 42. Namely, since the locking 
projections 47 are oppositely arranged, the male member 44 may be engaged 
with the female member 37 irrespective of the direction to the stoppers 
42. 
In the case that the opening W of the lid 36 is intended to be closed, the 
male member 44 is rotated to release a contact between the flat portion 23 
and the leg portions 7, and a side edge of the lid 36 is engaged with stop 
pawls 48 formed at an edge of the opening W. Then, the fastener 1 is 
inserted into a mount hole 50 formed through a receiving plate 49 
projecting into the opening W, and the handle 28 is rotated at 90 degrees. 
As a result, the flat portion 23 is rotated to elastically deform and 
spread the leg portions 7, and the stop projections 26 are engaged with 
the upper guide surfaces 17 to fix the lid 36 to the receiving plate 49. 
At the same time, one of the locking projections 47 is engaged with one of 
the locking recesses 41 to close the opening W. 
In the case that the lid 36 is intended to be removed, the handle 28 is 
rotated reversely at 90 degrees to forcibly contract the link portion 14 
as spread in the hollow portion 24 by the long sides in the direction of 
the width W of the flat portion 23. As a result, the leg portions 7 
connected to the link portion are also forcibly returned to their original 
condition. In this connection, the distance between both the leg portions 
7 is slightly smaller than the diameter of the mount hole 50, and the 
shoulder portions 25 of the flat portion 23 are engaged with the lower 
guide surfaces 18 of the engagement projections 16 of the female member 2. 
Then, the handle 28 is upwardly drawn to release the fixed condition of 
the receiving plate 49. 
Referring to FIGS. 18 to 26 showing a third preferred embodiment, reference 
numeral 1A generally designates a fastener for fixing plate-like members 
29A and 30A. The fastener 1A is composed of a female member 2A and a male 
member 19A. 
Reference numeral 3A designates a base plate of the female member 2A which 
plate is substantially flatly formed. The base plate 3A is formed with an 
elongated recess 4A having an insertion hole 5A for permitting insertion 
of the male member 19A. There are formed at a lower peripheral edge of the 
insertion hole 5A opposite stoppers 6A of substantially U-shape in 
section, and there are formed at the peripheral edge perpendicular to the 
stoppers 6A guides 15A adapted to come into contact with a peripheral edge 
of mount holes 31A and 32A of the plate-like members 29A and 30A. The 
stoppers 6A and the guides 15A are adapted to be inserted into the mount 
holes 31A and 32A. 
The stoppers 6A are formed with leg portions 7A downwardly extending along 
the peripheral edge of the insertion hole 5A corresponding to an arcuate 
edge of the recess 4A and with opposite engagement portions 14A as 
upwardly bent. The leg portions 7A are arcuate with a predetermined 
thickness at its base. The leg portions 7A are formed with outer arcuate 
surfaces 8A having the same arc extending near to its lower portion, and 
with slant surfaces 9A inclined to an axis side of the insert hole 5A at 
the lower portion. The leg portions 7A are further formed with inner 
arcuate surfaces 10A having slant surfaces 11A downwardly inclined near 
from its base to the axis side of the insert hole 5A and also having 
vertical surfaces 12A at its lower end portion. Thin-walled portions 13A 
are oppositely formed at the lower ends of the leg potions 7A. The 
engagement portions 14A are formed between both the thin-walled portions 
13A. That is, the leg portions 7A are integrally connected through the 
thin-walled portions 13A with the engagement portions 14A to thereby form 
the stoppers 6A of substantially U-shape in section. The leg portions 7A 
are elastically deformable so as to be spread about the base portion 
thereof, and the engagement portions 14A are adapted to be outwardly 
spread in cooperation with the elastic deformation of the leg portions 7A. 
Under a normal or unspread condition, a distance between the outer 
surfaces of the engagement portions 14A is set to a predetermined value 
h1, while a distance between the inner opposed surfaces is set to a 
predetermined value h2. 
The arcuate guides 15A are formed in a tongue-like shape as viewed in 
section with a predetermined thickness as extending from the peripheral 
edge of the insert hole 5A perpendicular to the stoppers 6A, and are 
adapted to come into contact with the peripheral edge of the mount holes 
31A and 32A of the plate-like members 29A and 30A. There are formed on the 
peripheral edge of the insertion hole 5A and the inside surface of the 
guides 15A engagement projections 16A having horizontal upper guide 
surfaces 17A and slanted lower guide surfaces 18A. The existence of the 
engagement projections 16A makes the insert hole 5A substantially 
rectangular with an arcuate portion. 
The male member 19A includes a substantially planar head portion 20A and a 
shaft portion 21A having a flat portion 23A adapted to be inserted into 
the insert hole 5A of the female member 2A. 
The shaft portion 21A is formed with a neck portion 22A having a 
predetermined diameter, that is, a diameter (d) allowed to be inserted 
between both the engagement projections 16A, and a predetermined length at 
a substantially central position of the head portion 20A. The flat portion 
23A is integrally formed with the neck portion 22A in such a manner as to 
downwardly extend therefrom. The flat portion 23A has a width W allowed to 
be inserted into the insert hole 5A and a thickness T equal to the 
diameter (d) of the neck portion 22A. Opposite outer surfaces of the flat 
portion 23A in the direction of the thickness T is formed arcuately. The 
flat portion 23A is further formed with a hollow portion 24A having a 
lower opening of substantially rectangular in section. A width of the 
lower opening of the hollow portion 24A in the direction of the width W is 
set to W1 permitting expansion of the engagement portions 14A of the 
female member 2A, while a width in the direction of the thickness T is set 
to T1 permitting insertion of the engagement portions 14A having the width 
h1 under the normal condition. The hollow portion 24A extends to the neck 
portion 22A. The flat portion 23A is formed at its upper part with 
shoulder portions 25A inclined at a predetermined angle from a junction of 
the neck portion 22A in the direction of the width W. The shoulder 
portions 25A are adapted to engage with the lower guide surfaces 18A 
formed at the engagement projections 16A of the female member 2A. The flat 
portion 23A is further formed at the junction of the neck portion 22A at 
the center in the direction of the width W with stop projections 26A 
adapted to engage with the upper guide surfaces 17A formed at the 
engagement projections 16A of the female member 2A. The stop projections 
26A are formed with slits 27A on both sides thereof, and are allowed to be 
elastically deformed. Reference numeral 28A designates a handle provided 
on the upper surface of the head portion 20A. 
In operation, when the stoppers 6A of the female member 2A are inserted 
into the mount holes 31A and 32A of the plate-like members 29A and 30A as 
registered, the base portions of the outer arcuate surfaces 8A of the leg 
portions 7A and the outer arcuate surfaces of the guides 15A are brought 
into contact with the edges of the mount holes 31A and 32A. Thereafter, 
when the flat portion 23A of the male member 19A is inserted into the 
insert hole 5A, both the side surfaces of the flat portion 23A in the 
direction of the thickness T are brought into contact with the vertical 
surfaces 12A of the inner arcuate surfaces 10A of the leg portions 7A, and 
the engagement portions 14A is inserted into the hollow portion 24A of the 
flat portion 23A. As the width W of the flat portion 23A is greater than 
the distance between both the vertical surfaces 12A of the leg portions 
7A, both the leg portions 7A are elastically deformed by the flat portion 
23A to be outwardly spread, and simultaneously the engagement portions 14A 
connected to the leg portions 7A are elastically deformed in the hollow 
portion 24A to be outwardly spread. With further insertion of the flat 
portion 23A, the stop projections 26A are brought into contact with the 
upper projected portions of the engagement projections 16A, and is 
elastically deformed to the hollow portion 24A side. Then, the stop 
projections 26A pass through the upper projected portions of the 
engagement projections 16A, and simultaneously they are elastically 
returned to its original condition to be engaged with the upper guide 
surfaces 17A of the engagement projections 16A. Thus, the leg portions 7A 
of the female member 2A are outwardly spread below the mount holes 31A and 
32A by the flat portion 23A of the male member 19A, and the stop 
projections 26A of the male member 19A are lockingly engaged with the 
engagement projections 16A of the female member 2A to intensively fix the 
plate-like members 29A and 30A. 
In the case that the fixed condition of the plate-like members 29A and 30A 
is intended to be released, the handle 28A provided at the head portion 
20A of the male member 19A is rotated at 90 degrees to rotate the flat 
portion 23A of the shaft portion 21A at 90 degrees about the neck portion 
22A and thereby release the spread condition of the leg portions 7A. Then, 
the stop projections 26A of the flat portion 23A are slided to be 
disengaged from the upper guide surfaces 17A. At the same time, the 
engagement portions 14A in the hollow portion 24A under the spread 
condition is forcibly contracted by the sides of the flat portion 23A in 
the direction of the width W, and the leg portions 7A are also forcibly 
returned to their original condition. As a result, the distance between 
both the leg portions 7A is slightly smaller than the diameter of the 
mount holes 31A and 32A, and the shoulder portions 25A of the flat portion 
23A are engaged with the lower guide surfaces 18A of the engagement 
projections 16A of the female member 2A. Then, the handle 28A is upwardly 
drawn to remove the male member 19A and the female member 2A as integrally 
fixed to each other and thereby release the fixed condition of the 
plate-like members 29A and 30A. 
In the case that the fastener 1A is intended to be fixed to the plate-like 
members 29A and 30A, the fastener 1A is inserted into the mount holes 31A 
and 32A, and the handle 28A is rotated at 90 degrees to rotate the flat 
portion 23A. As a result, the leg portions 7A are elastically deformed to 
be outwardly spread, and the stop projections 26A are engaged with the 
upper guide surfaces 17A to thereby fix the plate-like members 29A and 
30A. 
According to the fastener of the preferred embodiment, even if the leg 
portions 7A are creeped under the spread condition after a long time is 
elasped under such a condition where the female member 2A and the male 
member 19A are lockingly engaged with each other to fix the plate-like 
members 29A and 30A, the leg portions 7A may be forcibly returned to their 
original condition by rotating the male member 19A at 90 degrees and 
forcibly contracting the engagement portions 14A as spread with the aid of 
the flat portion 23A. Accordingly, in using the fastener again, the 
fastener may be easily inserted into the mount holes 31A and 32A without 
any inconvenience, and the plate-like members 29A and 30A may be securely 
fixed to each other. Further, both the engagement portions 14A may be 
arranged more nearly to reduce the width h2, so as to reduce a dimension 
of associated parts and thereby make a size of the fastener compact. The 
diameter of the mount holes 31A and 32A of the plate-like members 29A and 
30A may be also reduced to secure a strength of the plate-like members 29A 
and 30A. Further, as the female member 2A and the male member 19A are used 
as an assembly after both the members are once engaged with each other, 
handling of parts may be made easy. 
In substitution for the handle formed on the head portion of the male 
member, a groove may be formed at the head portion so as to be engaged and 
rotated by a flat screwdriver or a philips screwdriver for example. 
Although the female member is independent of the male member in the 
aforementioned embodiment, the lower opening edge of the flat portion of 
the male member may be integrally connected with the upper edge of the 
hole of the female member through a thin-walled breakable connection 
member for example. Further, although the engagement portions 14A in the 
third embodiment are arranged in opposed relation with each other at the 
predetermined distance h2, engagement portions 14B may be arranged in a 
counter manner as shown in FIG. 26, so as to reduce a size of the fastener 
as a whole. 
Having thus described the preferred embodiment of the invention, it should 
be understood that numerous structural modifications and adaptations may 
be made without departing from the spirit of the invention.