Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROUND OF INVENTION:
(a) Field of the Invention
The present invention relates to a cap for
securement over the head of the fastener and wherein
the cap is molded of synthetic resinous material and
is adapted for snap-fit over the head.
tb) Description of the Prior Art
It is advantageous to cover the head of a
fastener, such as a bolt or screw fastener, with a
synthetic resinous cover whereby to prevent corrosion
of the fastener or to cover the fastener with a colored
cap ~hereby to conceal the fastener from its surrounding
area, which may, for example, be the roof or side wall
of a building structure made of colored or natural metal
sheeting. Such caps have been provided and wherein the
cap has a cavity configured to be press fitted onto the
head of a fastener. The disadvantage of such covers is
that they become undone from the fastener due to various
reasons such as contraction and expansion of the cover
material caused by environmental temperature changes~
Also, such caps are often painted and are easily scratched
when handled during installation.
It is also known in the prior art to mold
synthetic resinous material about the head of a bolt such
as, for example, described in British patents 953,009 and
991,961. The disadvantage of such covers is that the
synthetic resinous material becomes damaged or soiled by
fastening tools when the fastener is secured and such
damage can cause the cover to fall off the fastener head,
or else is aesthetically unpleasant. Another disadvantage
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of such synthetic material cover is that it is costly to
fabricate and it is necessary to maintain a large inventory
of fasteners as different types of fasteners are stocked
and each type having covers of different colors. Such
stock-keeping is very expensive.
SUMMARY OF INVENTION
It is a feature of the present invention to
provide a cap for securement over the head of a fastener
and which substantially overcomes the above-mentioned
disadvantages of the prior art.
Another feature of the present invention is to
provide a cap for securement over the head of a fastener
and wherein the cap is molded of synthetic resinous
material and is provided with channel means for receiving
in snap-fit engagement therein a lower circumferential
flange of a fastener head to secure the cap over the
fastener head.
Another feature of the present invention is to
provide a cap for securement over the head oE a fastener
and wherein the cap is provided with an annular skirt
whereby to also receive therein an ~nmll~r dome-shaped
cover located under the fastener head.
According to the above featuresl from a broad
aspect, the present invention provides a cap or securement
over the head of a fastener and wherein an annular dome-
shaped cover is located under the fastener head to compress
a flexible annular washer disposed about a fastener shank.
The cap is molded of synthetic resinous material and has a
hol low head portion and a cap attachment portion. The head
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portion has a top wall and an integral annular side wall.
The attachment portion is formed integral with the annular
side wall and is disposed circumferentially below the side
wall. The attachment portion has an annular channel in an
inner wall thereof for receiving in snap-fit engagement
therein a circumferential flange of a fastener head to
secure the cap over the fastener head. A circumferential
shoulder ~ortion is formed below the inner annular channel.
An outwardly flared annular tapering skirt depends from the
shoulder portion, and has a concave outwardly tapering
inner wall defining a flexible lip. The skirt is of a length
sufficiently long to receive thereunder the dome-shaped cover
and flexible annular washer. The sklrt is also thinner in
thickness than the head portion and more resilient for
greater flexibility.
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BRI~F DESCRIPTION OF DRAWI~GS:
A preferred embodiment of the present invention
will now be described with reference to the example
thereof as illustrated in the accompanying drawings, in
which:
FIGURE 1 is a cross-section view of the cap of
the present invention,
FIGURE 2 is a cross-section view of the cap as
shown in engagement over the head of a fastener having an
annular dome-shaped washer cover with a washer located
thereunder, and
FIGURB 3 is a cross-section view of the cap
showing alternate examples of the cap construction.
DESCRIPTIO~ OF PREFERRED EMBODIMENTS:
Referring now to the drawings and more parti~u-~
larly to Figures 1 and 2~ there is shown generaLly at 10
the cap of the present invention which is adapted to be
secured over the head 11 o~ a fastener 12. The cap is
molded of synthetic resinous material, such as poly-
propylene, and defines a hollow head portion 13 and a cap
attachment portion 14. The head portion defines a top
wall 15 and an integral annular side wall 16.
The cap attachment portion 14 is constituted by
an annular channel 17 formed in the inner wall 18 of the
cap adjacent the circumferential free edge 19 thereof
(see Figure 3). As shown in Figure 1, a circumferential
shoulder portion 20 is formed adjacent the lower
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circumferential free edge of the cap whereby to
accommodate the circumferential channel 17 therein.
Also, an annular skirt 21 is formed in the lower edge
19 and is provided with an inner concave surface 22 whereby
to abut over an annular dome-shaped cover 23 located under
the fastener head 11 and receiving therein a rubber washer
24 for compressing same between a surface (not shown) to
which the fastener is secured to and the underside of the
fastener head 11'. Also, as shown in Figure 1, the annular
skirt 21 is sufficiently long to cover the dome-shaped
cover 23 and is thinner than the remaining portion of the
cover whereby to be of greater flexibility to permit the
shoulder portion 20 to flex outwardly to provide for the
entry of the bolt head 11 therein and the circumferential
flange 11" of the head.
The annular recess 17 is of substantially
U-shape cross-section and defines a flat bottom wall 25
and opposed transverse side walls 25' and 25`'. The lower
one 25" of the side walls terminates in a tapered end 2
which is formed by the concave undercut 22 whereby to
constitute a flexible lip to permit snap-fit retention of
the bolt head flange 11" therein. Thus, to install the
cover on the fastener 11, it is simply necessary to push
the cover over the bolt head with the fingers by applying
pressure over the head causing the circumferential
shoulder portion 20 to flex outwardly until the bolt head
flange 11' is received in snap-fit engagement in the
channel 17. Also, as seen in Figures 1 and 2, the circum-
ferential shoulder portion 20 is outwardly sloped whereby
to facilitate outward flexion thereof when the cap is
positioned for securement over the fastener head~
Referring now to Figure 3, there is shown
alternate examples of the construction of the cap of this
invention. It is firstly pointed out that the cap may
be molded with any desirable outer cross-sectional shape.
~s is shown in Figures l and 2, the cap is of circular
cross-section but may also be of hexagonal cross-section
or have any other shape. Also, the cap may be molded of
a colored synthetic plastic material. As herein shown,
the circumferential free edge l9 of the cap does not have
an annular skirti such as 21 in Figures l and 2, formed
therewith as it is not intended to cover a dome-shaped
washer cover. The lip 26 formed in the lower edge l9
may either extend entirely about the circumference of the
lower edge or may extend about small spaced-apart portions
to constitute at least two channel portions 27 to grip
under the flange llU of the bolt head 11'. Preferably,
although not exclusively, the lower edge portion under
the side wall 25" is sloped such as at 26' to define a
tapered end 26 to facilitate entry of the bolt head flange
ll" by making the lip more resilient.
It is within the ambit of the present invention
to cover any other obvious modifications of the cap o the
present invention provided such modifications fall within
the scope of the appended claims.
