UNITARY HOLDING STRIP FOR RETAINING A PLURALITY OF SCREWS IN A ROW

BANDE PLASTIQUE D'UN SEUL TENANT SERVANT A RETENIR ET A PRESENTER LES VIS EN RANGEE

English Abstract

ABSTRACT OF THE DISCLOSURE:
A unitary holding strip made of plastics material for
retaining a plurality of screws in a row, the screws having
longitudinal axes and a threading with a given outer thread
diameter, which unitary holding strip includes a plurality
of screw holding sleeves and lands interconnecting the sleeves
which extend along a portion of the threaded length of the
respective screw in the axial direction thereof and comprise
inwardly facing screw threads for receiving the screw threading.
The unitary holding strip of the invention is characterized in that
the sleeves completely surround the screw threading and are formed
with longitudinally aligned perforations along one side thereof,
substantially between the lands, defining an area of reduced
strength such that a screw which is being threaded into a work-
piece is automatically separated from its sleeve while simul-
taneously maintaining the length of the strip substantially intact
and while guiding the screw by the inwardly facing screw threads
of the respective sleeve.

Claims

The embodiments of the invention in which an exclusive
property or privilege is claimed are defined as follows:
1. In a unitary holding strip made of plastics material
for retaining a plurality of screws in a row, the screws having
longitudinal axes and a threading with a given outer thread
diameter, said unitary holding strip including a plurality of
screw holding sleeves and lands interconnecting the sleeves which
extend along a portion of the threaded length of the respective
screw in the axial direction thereof and comprise inwardly facing
screw threads for receiving the screw threading, the improvement
wherein the sleeves completely surround the screw threading and
are formed with longitudinally aligned perforations along one side
thereof, substantially between the lands, defining an area of
reduced strength such that a screw which is being threaded into a
workpiece is automatically separated from its sleeve while
simultaneously maintaining the length of the strip substantially
intact and while guiding the screw by the inwardly facing screw
threads of the respective sleeve.
2. A strip according to claim 1, wherein the perforations
are formed by strap-like wall portions in each sleeve.
3. A strip according to claims 1 or 2, wherein each
interconnecting land is formed with a rib on at least one side
thereof, the rib extending substantially along the entire length
of the strip.

Description

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The present lnven-tion relates to improvements in a
, unitary holding strip made of plastics material for retaining a
plurality of screws in a row, of the type described in Canadian
application No. 245,738 filed February 13, 1976 (inventors: Keusch
et al). ~uch unitary holding strip includes a plurality of screw
holding sleeves and lands interconnecting the sleeves which extend
along a portion of the threaded length of the respective screw
in the axial direction thereof, the lands and sleeves having a
wall thickness substantially smaller than the outer thread diameter
of the screws. The sleeves comprise inwardly facing screw threads
for receiving the screw threading and along one side thereof,
substantially between the lands, an area of reduced strength such
that a screw which is being threadedVinto a workpiece is automa-
i . .
tically separated from its sleeve while simultaneously maintaining
~ the length of the strip substantially intact and while guiding the `
`r screw by ~he inwardly facing threads of the respective sleeve.
The presence of the inwardly facing screw threads in the
sleeves provides the advantage that during screwing-in a screw
. :
,` can be positively guided until it has penetrated at least partly
into the workpiece and is then guided by the latter. When the head
~; of the screw reaches a weakened wall area of the sleeve, the latter
is forced apart or is split so that the screw can leave it easily.
The empty strip can then leave the screw driving tool without
broken remnants remaining to clog the tool or damage the surface
of the workpiece. In addition, the prior strip gave the advantage
of higher production speed at lower cost.
It is an object of the present invention to form a
weakened wall area of the sleeve in such a way that the sleeve
holds a screw securely, guides it reliably during a screwing-in
operation, and ensures its ready release even in cases where, due
to poor production conditions during extrusion of plastics material
` onto a row of screws, variations occur in the formation ofthe sleeves.
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~135~
According to the invention therefore there is provided
a unitary holding strip made of plas-tics material for retaining
a plurality of screws in a row, the screws having longitudinal
axes and a threading with a given outer thread diameter, which
unitary holding strip includes a plurality of screw holding sleeves
and lands interconnecting the sleeves which extend along a portion :
of the threaded length of the respective screw in the axial
direction thereof and comprise inwardly facing screw threads
for receiving the screw threading. The unitary holding strip of .-
the invention is characterized in that the sleeves completely
surroundthe screw threading and are formed with longitudinally
~', aligned perforations along one side thereof, substantially between
the lands, defining an area of reduced strength such that a screw .
which is being threaded into a workpiece is automatically
. separated from its sleeve while simultaneously maintaining the
length of the strip substantially intact and while guiding the
screw by the inwardly facing screw threads of the respective
. sleeve. .
The perforations may be formed by providing strap-like
wall portions in each sleeve. The advantages of the invention
; are thus retained even if, due to poor production conditions
during extrusion of plastics material onto a row of screws,
variations occur in the formation of the sleeves.
A preferred embodiment of the invention will now be :.
. described in greater detail with reference to the appended
drawings, in which:
Figure 1 is a side view of part of a screw strip
according to the invention;
. Figure 2 shows a cross section along line II-II of . ,
. 30 Figure l; and :
: Figure 3 shows a cross section along line III~III of
... Figure 1.
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Referring to the drawing, Figure 1 shows part of a screw
strip 1, the parallel screws of which each have a shank 3, a screw
thread 4 and a head 5. To hold the screws 2 there is a holding
strip 6 of elastic plastics material which extends perpendicularly
to the axes of the screws. However, the strip can also be slightly
inclined to the axes of the screws in a screw strip in which the
screws are off-set from each other.
Each screw thread is encircled by a sleeve 7 in the strip
6 over part of its circumference, the rest of the circumference
being secured by strap-like wall portions 8 which are integral
with the sleeve 7. The strip 6 therefore has a weakened wall area ;
9 on one side, in that the sleeve 7 has perforations 10 formed by
the strap-like wall portions 8.
The mating thread 11 formed on the inside of each sleeve
7 mates with the screw thread 4. Further, the sleeves 7 are
connected together by lands 12 which are integral with them, the
lands 12 being arranged in the median plane o~ the strip 6. On :
one side of the strip each land 12 has a rib 13 and the ribs extend
along the entire length of the strip 6.
The screw strips 1 shown in Figures 1 and 3 have a part
at their right-hand outer end where the screw 2 has already been
released from the sleeve 7. The portions 8 have been burst apart,
but still remain connected to the rest of the sleeve 7 so that the
empty strip 6 can leave the screw-driving tool through a suitable
opening.
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