Wall fastener

A wall fastener comprising a hollow conical member, a cylindrical sleeve member disposed substantially within the conical member, an anchoring member attached to the sleeve member for engaging the inner surface of a hollow wall and a rotatable threaded member extending through aligned openings in the conical member, sleeve member and anchoring member for tightly securing the fastener to the wall. The anchoring member is comprised of a central housing and a plurality of resilient curved feet flared outwardly from the housing. The feet are bendable toward the axis of the threaded member to allow the anchoring member to be inserted through a hole in the wall. When the anchoring member has cleaned the hole, the feet are spring-biased to return to the outwardly flared position to engage the inner surface of the wall. As the threaded member is tightened, the feet are compressed against the inner surface of the wall, which causes the feet to flatten and expand outwardly to engage the inner surface of the wall at a greater distance from the hole, thereby providing a more secure attachment of the fastener to the wall. The conical member, sleeve member and anchoring member are fixed against rotation with respect to the threaded member to prevent the fastener from damaging the wall in the event that the threaded member is over-torqued.

FIELD OF THE INVENTION 
The present invention relates generally to wall fasteners and in particular 
to a fastener used in connection with hollow walls made of lightweight 
material, such as gypsum board or the like. 
BACKGROUND OF THE INVENTION 
Wall fasteners are typically installed in hollow walls made of lightweight 
material, such as gypsum board, to attach objects to the wall. Such 
fasteners are useful in supporting relative heavy objects, such as framed 
pictures, which are attached to the wall. 
DESCRIPTION OF THE PRIOR ART 
According to prior practice, fasteners installed in hollow walls are 
comprised of a threaded member, such as a bolt or screw, and an anchoring 
mechanism. Rotation of the threaded member causes the anchoring mechanism 
to expand and contact the inside of the wall to anchor the fastener in 
place. Common examples of such fasteners are the so-called "toggle" bolts 
and "moly" bolts. Various types of fasteners are described in the 
following U.S. Pat. Nos.: 4,136,599; 4,086,840; 4,077,300; 3,905,570; 
3,874,264; 3,869,958; 3,752,032; 3,701,302; 3,605,846; 3,555,960; 
3,534,797; 3,487,746; 3,366,405; 3,315,558; 3,211,044; 3,136,350; 
3,104,582; and 1,978,935. 
One problem associated with such prior art fasteners is that a portion of 
the anchoring mechanism is usually received within the hole in the wall 
through which the fastener is inserted. Therefore, stress exerted by heavy 
objects attached to the fastener on the outside of the wall may cause the 
fastener to pull outwardly through the opening. Another problem is that 
such fasteners must be carefully installed to insure that they are 
over-torqued. Continued twisting of the threaded bolt or screw after the 
anchoring mechanism has contacted the inner surface of the wall will cause 
the anchoring mechanism to twist and dig into the inner surface of the 
wall. This digging action scours out the wall hole, which increases the 
size of the hole and causes the fastener to fit loosely within the wall, 
thereby increasing the likelihood that the fastener will become dislodged 
from the wall. 
OBJECTS OF THE INVENTION 
It is therefore the principal object of the present invention to provide an 
improved wall fastener. 
It is another object of the invention to provide an improved fastener for 
use in connection with hollow walls made of lightweight material, such as 
gypsum board. 
It is yet another object of the invention to provide a fastener which can 
be securely anchored within a hole formed in a hollow wall. 
It is a further object of the invention to provide a fastener which allows 
relatively heavy objects to be attached to a hollow wall, wherein the 
stresses exerted by such objects are distributed over a relatively wide 
area around the wall hole in which the fastener is anchored. 
It is still a further object of the invention to provide a fastener having 
a rotatable threaded member and an anchoring member in which the twisting 
action of the threaded member does not rotate the anchoring member. 
SUMMARY OF THE INVENTION 
These and other objects are accomplished in accordance with the present 
invention wherein a fastener adapted for insertion within a hole extending 
through a wall is provided. The fastener is comprised of a conical member 
tapering downward from a first end to a second end thereof and having an 
opening extending axially therethrough; an anchoring member disposed 
adjacent to the second end of the conical member; means for attaching the 
anchoring member to the conical member so that the anchoring member is 
fixed against rotation with respect to the conical member; and a threaded 
member extending through respective aligned openings in the conical member 
and anchoring member and being in engagement with complementary threads 
within the opening in the anchoring member. The conical member and 
anchoring member are fixed against rotation so that the threaded member is 
freely rotatable with respect to the conical member, sleeve member and 
anchoring member. 
In one aspect of the invention the anchoring member is comprised of a 
central housing and a plurality of resilient feet curved outwardly from 
the central housing for engaging an inner surface of the wall to anchor 
the fastener to the wall. The feet are bendable in the direction of the 
threaded member to allow the anchoring member to be inserted through the 
wall hole and are spring-biased to expand outwardly from the threaded 
member to engage the inner surface of the wall when the anchoring member 
clears the hole on the inside of the wall. 
In another aspect of the invention the feet are compressible against the 
inner surface of the wall in response to the rotation of the threaded 
member in a predetermined direction, so that the feet tend to flatten and 
engage the inner surface of the wall at a greater distance outward from 
the perimeter of the hole in response to an increased compressive force 
resulting from the continued rotation of the threaded member in the 
predetermined direction. 
In the preferred embodiment the fastener includes a sleeve member threaded 
on an inner surface thereof and disposed substantially within the opening 
in the conical member. The conical member, sleeve member and anchoring 
member are comprised of a lightweight plastic material. The conical member 
preferably includes first and second opposite tab members adjacent to the 
second end thereof, which extend radially into the opening in the conical 
member. The sleeve member has first and second opposite grooves on an 
outer surface thereof for mating with the first and second tab members to 
fix the sleeve member against rotation with respect to the conical member. 
The sleeve member further includes a retaining member for engaging the 
first and second tab members within the opening in the conical member to 
limit the axial movement of the sleeve member with respect to the conical 
member. 
The fastener preferably includes a relatively flat washer member for 
engaging an outer surface of the wall around the perimeter of the hole. 
The washer member has a central opening therein for receiving the threaded 
member. The threaded member is preferably comprised of a screw having a 
head on one end thereof, which is substantially wider than the diameter of 
the shaft of the screw. The head is also wider than the diameter of the 
central opening of the washer member so that the washer member is 
sandwiched between the outer surface of the wall and the screw head to 
provide a compression fitting to enhance the locking action imparted to 
the fastener when the screw is rotated in the predetermined direction. A 
plurality of rib members are disposed on the outer surface of the conical 
member for locking the conical member in place within the hole to prevent 
rotation of the conical member, sleeve member and anchoring member.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
In the description which follows, like parts are marked throughout the 
specification and drawings, respectively. The drawings are not necessarily 
to scale and in some instances proportions have been exaggerated in order 
to more clearly depict certain features of the invention. 
Referring to FIGS. 1-4, a wall fastener 11 according to the present 
invention is comprised of a conical member 13, cylindrial sleeve member 
15, anchoring member 17 and threaded member 19. In FIG. 1 sleeve member 15 
is shown removed from conical member 13. When fastener 11 is assembled, 
sleeve member 15 is substantially disposed within a cylindrical chamber 21 
extending axially between respective openings in first and second ends 23 
and 25 of conical member 13. Sleeve member 15 has a tapered base portion 
27 at one end thereof and an annular retaining member 29 just above base 
portion 27. Retaining member 29 is slightly wider than main cylindrical 
body portion 30 of sleeve member 15. Anchoring member 17 is preferably 
integrally formed on the opposite end of the sleeve member 15 from base 
portion 27. 
Main cylindrical body portion 30 of sleeve member 15 has a pair of 
diametrically opposed grooves 31 (only one of which is shown in FIG. 1) 
extending substantially along the entire length of sleeve member 15 
between base portion 27 and anchoring member 17. Sleeve member 15 also has 
a pair of diametrically opposed slits 37 (only one of which is shown in 
FIG. 1), which extend through base portion 27, retaining member 29 and 
partially upwardly along main cylindrical body portion 30 of sleeve member 
15. Slits 37 are each disposed at substantially equal angular intervals 
between grooves 31. Slits 37 cooperate with tapered base portion 27 to 
allow retaining ring 29 to be compressed sufficiently to reduce the 
diameter thereof to allow retaining member 29 to fit through the opening 
in second end 25 of conical member 13 when sleeve member 15 is inserted 
into cylindrical chamber 21. 
Conical member 13 has a pair of diametrically opposed tab members 41 and 43 
projecting radially into cylindrical chamber 21, adjacent to second end 
25. In order to insert sleeve member 15 into cylindrical chamber 21, base 
portion 27 and retaining member 29 must be compressed sufficiently to 
enable retaining member 29 to clear tab members 41 and 43. The spring bias 
of the material will cause retaining member 29 to expand outwardly and 
engage the inner walls of cylindrical chamber 21 to provide a friction fit 
between sleeve member 15 and conical member 13 within chamber 21. 
An annular spacing 45 is maintained between main body portion 30 and the 
inner wall of chamber 21 (as best seen in FIG. 4) by virtue of retaining 
member 29, which extends slightly outward (e.g., on the order of 1/32 
inch) from main body portion 30. Sleeve member 15 is of substantially the 
same length as conical member 13 so that when sleeve member 15 is properly 
received within chamber 21, a portion of sleeve member 25 adjacent to 
anchoring member 17 protrudes slightly outward from chamber 21 adjacent to 
second end 25 and a corresponding spacing 47 is defined between base 
portion 27 and first end 23 of conical member 13 to allow sleeve member 15 
room to move in the direction of first end 23 when fastener 11 is 
tightened by means of threaded member 19. Sleeve member 15 is oriented 
with respect to conical member 13, such that tab members 41 and 43 will 
mate with complementary respective grooves 31, thereby fixing sleeve 
member 15 against rotation with respect to conical member 13, as best seen 
in FIG. 3. 
Anchoring member 17 is comprised of a housing 49 having a threaded central 
opening 51 extending therethrough and a plurality of curved feet 53 flared 
outwardly from housing 49. Feet 53 are sufficiently resilient so as to be 
bendable in the direction of main body portion 30 to allow anchoring 
member 17 to be inserted through a wall hole. After anchoring member 17 
clears the hole on the inside of the wall, the spring bias of feet 53 will 
return feet 53 to the outwardly flared position for engaging the inner 
surface of the wall, as best seen in FIG. 4. Central opening 51 in housing 
49 is aligned with the corresponding opening 55 extending axially through 
sleeve member 15 for receiving threaded member 19. 
Threaded member 19 is preferably comprised of a threaded screw or bolt 
having a head 57 on one end thereof which is substantially wider than the 
diameter of the main shaft portion of threaded member 19. Threaded member 
19 is of sufficient length to extend all the way through concial member 
13, sleeve member 15 and anchoring member 17. The respective surfaces 
surrounding the corresponding aligned openings in housing 49 and sleeve 
member 15 are threaded to engage the complementary threads on threaded 
member 19, so that the rotation of threaded member 19 will cause sleeve 
member 15 and anchoring member 17 to move axially with respect to conical 
member 13. The axial movement of sleeve member 15 and anchoring member 17 
is limited in the direction of first end 23 by the engagement of second 
end 25 with flared feet 53 and in the direction of second end 25 by the 
engagement of tab members 41 and 43 with retaining member 29, as best 
shown in FIG. 2. In this manner, sleeve member 15 is prevented from 
accidentally becoming dislodged from chamber 21. 
Referring specifically to FIG. 4, fastener 11 is installed in a hollow wall 
made of a lightweight material, such as gypsum board or sheetrock, by 
first boring a hole in wall 59 using a tap tool or the like. Feet 53 are 
then compressed in the direction of sleeve member 15 to allow anchoring 
member 17 to be inserted through the hole from the outside of wall 59 to 
the inside thereof. The hole formed in wall 59 should be sufficiently 
large to allow anchoring member 17 to be inserted therethrough and conical 
member 13 to be received therein, but should be small enough to provide a 
tight friction fit between the portion of wall 59 surrounding the hole and 
the outer surface of conical member 13. 
Referring also to FIG. 1, conical member 13 has a plurality of elongated 
ribs 61 disposed around the perimeter thereof for enhancing the friction 
fit between outer surface 63 of conical member 13 and the portion of the 
wall surrounding the hole. It is important that conical member 13 be 
securely held within the wall hole to prevent rotation of conical member 
13 when a torque is applied to threaded member 19. 
One skilled in the art will appreciate that the rotation of threaded member 
19 is used to selectively tighten or loosen the attachment of fastener 11 
on wall 59. If the conventional right-hand threaded screw is used as 
threaded member 19, the rotation of threaded member 19 in a clockwise 
direction, as viewed from outside wall 59, will cause sleeve member 15 and 
anchoring member 17 to migrate along threaded member 19 in the direction 
of head 57. This action compresses feet 53 against inner surface 65 of 
wall 59, thereby causing feet 53 to flatten and expand farther outward 
from housing 49. This not only tightens the attachment of fastener 11 to 
wall 59, but also causes feet 53 to engage inner surface 65 at a greater 
distance from the perimeter of the wall hole. Thus, any stresses exerted 
on fastener 11 will be distributed by feet 53 over a comparatively wider 
area of inner surface 65 around the wall hole, thereby enhancing the 
strength of the attachment and reducing the likelihood that the sheetrock 
wall will be broken or damaged due to excessive stresses caused by the 
weight of an object hanging on fastener 11 on the outside of wall 59. 
Disposed between first end 23 of conical member 13 and head 57 of threaded 
member 19 is a relatively flat washer member 67. Washer member 67 is 
preferably integrally formed on first end 23. Washer member 67 has a 
central opening disposed in alignment with and having substantially the 
same diameter as cylindrical chamber 21 for receiving the shaft of 
threaded member 19. The diameter of the central opening is sufficiently 
small to prevent head 57 from penetrating into the central opening. As a 
result, washer member 67 is sandwiched between head 57 and outer surface 
69 of wall 59 to provide a compression fitting as torque is applied to 
threaded member 19. Washer member 67 cooperates with anchoring member 17 
to hold fastener 11 securely in position on wall 59 and to distribute 
stresses exerted on fastener member 11 over a relatively wide area 
surrounding the hole. 
When fastener member 11 is properly installed in wall 59, conical member 13 
is disposed completely within the hole such that first end 23 is 
substantially coterminous with outer surface 69 and second end 25 is 
slightly recessed, as indicated at 71, from inner surface 65 inside wall 
59. Thus, the length of concial member 13 is preferably slightly less than 
the thickness of wall 59. One skilled in the art will recognize that the 
length of conical member 13 is a function of the thickness of wall 59. 
Furthermore, multiple layers of sheetrock or gypsum board may be 
sandwiched together to form wall 59 and secured together by means of a 
single wall fastener 11, which extends through the multiple layers. 
Referring to FIGS. 5 and 6, an alternate embodiment of the wall fastener 
according to the present invention is depicted. In this embodiment sleeve 
member 15 is replaced by a pair of legs 73, which are attached at 
respective first ends thereof to anchoring member 75 and at respective 
second ends thereof to washer member 77, which is integrally formed on one 
end of conical member 78. Ribs 79 are disposed on the outer surface of 
conical member 78 for engaging the inside of the wall surrounding the wall 
hole to enhance the friction fit between the fastener and the inside of 
the wall, as described above with reference to FIGS. 1-4, to prevent 
conical member 78 from being rotated. Legs 73 fix anchoring member 75 
against rotation with respect to conical member 78. 
Anchoring member 75 is comprised of a housing 80 having a threaded central 
opening 81 extending therethrough and a plurality of curved feet 83 flared 
outwardly from housing 80. Feet 83 operate in substantially the same 
manner as feet 53, described above with reference to FIGS. 1-4. Respective 
first ends of legs 73 are permanently attached to housing 80 and 
respective second ends of legs 73 are inserted through respective openings 
85 in washer member 77. After the fastener is secured in the wall, the 
portions of legs 73 which extend through openings 85 may be clipped off. 
One skilled in the art will recognize that legs 73 may be permanently 
attached at both ends to housing 80 and washer member 77 or, 
alternatively, the respective second ends may be permanently attached to 
washer member 77 and the respective first ends may be removably attached 
to anchoring member 75, such as by inserting the respective first ends 
through complementary openings (not shown) in anchoring member 75. A 
threaded member 87 extends through the aligned openings in conical member 
79 and anchoring member 75, as shown in FIG. 6, and engages complementary 
threads within opening 81. 
Referring to FIGS. 7, 8A and 8B, yet another alternate embodiment of the 
wall fastener is illustrated. This embodiment is substantially the same as 
the embodiment described above with reference to FIGS. 5 and 6, except 
that legs 73' are permanently attached at their respective ends to both 
anchoring member 75' and conical member 78'. As illustrated in FIGS. 8A 
and 8B, legs 73' are beveled, as indicated at 89, on their outer surfaces 
adjacent to their respective ends and notched, as indicated at 91, on 
their inner surfaces at their respective centers to allow legs 73' to 
collapse and expand outwardly from an extended position (as shown in FIG. 
8A) to a folded position (as shown in FIG. 8B) when anchoring member 75' 
is drawn in the direction of conical member 78' by the rotation of the 
threaded member extending through the aligned openings in conical member 
78' and anchoring member 75'. 
The embodiments depicted in FIGS. 5-8 are particularly well-suited for 
being used in connection with relatively thin materials, such as particle 
board or thin sheetrock material (i.e., on the order of 1/4 inch or less). 
The wall fastener according to the present invention solves many of the 
problems associated with prior art fasteners. All of the components of the 
fastener are fixed against rotation except for the threaded member, which 
eliminates the danger of breaking or damaging the sheetrock as a result of 
over- torquing the threaded member. Furthermore, any axially directed 
force which tends to pull the fastener out of the wall will compress the 
feet of the anchoring member, causing them to spread out even more and 
engage a wider area of the inner surface of the wall around the hole to 
prevent the fastener from being removed. The major components of the 
fastener, except for the threaded member, are preferably comprised of a 
lightweight plastic material, but any suitable material other than plastic 
may be used to form these components, provided that the feet of the 
anchoring member are sufficiently resilient and yet rigid enough to 
provide the capabilities described above. 
Various embodiments of the invention have been described in detail. Since 
it is obvious that many changes in and additions to the above described 
preferred embodiment may be made without departing from the nature, spirit 
and scope of the invention, the invention is not to be limited to said 
details except as set forth in the appended claims.