Note: Descriptions are shown in the official language in which they were submitted.
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Title: "A slide fastener and a top stop for a slide
fastener"
DESCRIPTION
Field of application
The present invention refers to a slide fastener and to a
top stop of a slide fastener. The invention relates in
particular to fluid-tight slide fasteners and top stops of
fluid-tight slide fasteners.
Prior Art
A slide fastener, in essential terms, comprises a pair of
tapes bearing respective rows of teeth, top and bottom
stops, and a slider for opening and closing the fastener by
engaging and disengaging the teeth. The slider is operated
by a puller (or pull-tab) which is usually connected to the
slider by a ring or a ring shaped end portion of the same
puller.
The top and bottom stops are at opposite ends of the slide
fastener, which is completely closed when the slider
reaches the top stop.
Fluid-tight slide fasteners, in particular, are used in
sports and outdoor activity items, diving or sailing suits,
camping tents and the like, and are required to securely
prevent the passage of a liquid and/or gas, e.g. water
and/or air. In some cases, a fluid-tight fastener must
ensure fluid-tightness even under a significant pressure
difference between the interior and the exterior, for
example up to about 2 bars.
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Fluid-tight slide fasteners are realized for example with
layered tapes made of a textile core with a waterproof
coating layer, and injection-molded teeth.
The slider of a slide fastener, more in detail, comprises
upper and lower blades, lateral flanges and a central
portion, called diamond, connecting the upper and lower
blades. In known slide fasteners, especially fluid-tight
slide fasteners, the top stop is a substantially U-shaped
element with leg portions defining a front opening for the
diamond of the slider, and a seat for receiving said
diamond when the slide fastener is fully closed. It is
known technique to provide a suitable shape of the lateral
flanges of the slider so that they act on the sides of said
leg portions of the U-shaped top stop, in order to close
said front opening in a fluid-tight manner when the slider
reaches the full-closed position.
It can be understood that, in order to guarantee the fluid-
tightness of the closed slide fastener, during the use, the
slider should be kept in position and prevented from moving
away from the top stop. In fact, an accidental displacement
of the slider, even of few tenths of a millimeter, may
compromise the fluid-tightness of the fastener at the
region of the top stop and/or between the teeth.
Nevertheless, the user must always be able to open the
slide fastener quickly, also for safety reasons. These
needs are felt, in particular, in the field of fluid-tight
slide fasteners for waterproof items such as diving suits,
military or fireman suits, and the like.
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Summary of the invention
The technical problem underlying the invention is to
provide a reliable and safe closure of a slide fastener as
defined above, avoiding the slider from leaving the
position where the fastener is fully closed, allowing at
the same time a quick and easy opening of the fastener
itself.
This problem is solved by a slide fastener comprising a
pair of tapes, carrying respective teeth, a top stop and a
slider comprising a puller, the slider being movable up to
a closing position of the fastener where said slider is in
contact with said top stop, characterized in that the top
stop comprises at least one retaining element adapted to
retain the slider in said closing position.
According to a further aspect of the invention, said at
least one retaining element is integrally formed with the
top stop.
According to another aspect of the invention, said
retaining element is disposed to act as a stop means for
the slider when the puller is fitted on the top stop in a
determined locking position. Preferably, said locking
position is a position where the puller is lying on the top
stop, substantially parallel to the sliding direction of
the slider.
In a preferred embodiment, a retaining element is
integrally formed with the top stop, having a surface
disposed to act as a stop means against a contact face of
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the puller, when the puller is fitted on the top stop in
said locking position.
According to further aspects of the invention, the top stop
further comprises at least one locking element, adapted to
a snap engagement with a suitable seat or portion of the
puller, to retain the puller in said locking position.
Preferably, said seat or portion of the puller is a ring or
a ring portion connecting the puller to the slider.
In a preferred embodiment, said at least one locking
element is an elastically deformable element adapted to
snap on the ring connecting the puller to the slider.
Preferably, said locking element has an elastically
deformable stem portion and a head portion projected from
top of the stem portion, defining an undercut recess for
receiving the ring of the puller.
Said locking element(s), according to the invention, are
able to engage/disengage the ring of the slider by elastic
deformation induced by contact with the ring itself when
the puller is locked or unlocked on the top stop.
Preferably, the head portion of the locking elements has a
suitably profiled surface to allow deformation of the
element by contact with the ring of the slider, while the
puller is pressed down to the locking position, or lifted
from that position. Thanks to said profiled surface,
contact with the ring of the puller results in a force
directed to deform the locking element(s) in such a way to
receive or, respectively, to free the ring of the puller,
as will be clearer hereinbelow with the help of an example.
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According to a particularly preferred embodiment, said at
least one retaining element of the top stop is formed as a
wall of the top stop, comprising a base part with a surface
adapted to act as a stop means against a contact face of
5 the puller, and two locking elements formed as elastically
deformable toothed elements projecting upwards from said
base part and each defining an undercut recess for
receiving the ring of the puller.
More in detail, the base part of the wall integrally formed
with the top stop has a front surface facing the slider and
a rear surface adapted to act as a stop means against a
bottom face of the puller, to retain the slider when the
puller is in the locking position.
According to another aspect of the invention, the top stop
comprises at least one pin adapted to engage a
corresponding hole of the puller, to retain the puller from
lateral movement.
In further embodiments of the invention, the retaining
element is adapted to cooperate with a corresponding
locking element of the slider. As an example, the top stop
has a suitable seat or recess for receiving a locking
element projecting from the front of the slider, the
locking element of the slider being engaged in said seat or
recess of the top stop when the slider reaches the top
stop. In these further embodiments, a disengagement system,
e.g. by pressing a disengagement button, can also be
provided on the top stop, to unlock the slider.
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An object of the invention is also a top stop for a slide
fastener, the slide fastener comprising a pair of tapes,
carrying respective teeth, and a slider comprising a
puller, the slider being movable to a closing position
where said teeth are fully engaged and the slider is in
contact with the top stop, the top stop being characterized
by comprising at least one retaining element(s) as
described above.
In particular, the invention provides a top stop for a
slide fastener wherein said at least one retaining element
is formed as a front wall of the top stop, the top stop
being adapted to receive the puller of the slider in a
locking position, said front wall comprising a surface
adapted to act as a stop means against a contact face of
the puller when the puller is fitted in said locking
position.
The invention has the advantage that the slider is securely
kept in the closing position. It should be noted that the
snap-on engagement between the locking elements and the
slider, namely the puller thereof, provides a quick and
sinlple locking/unlocking action, so that the slider of the
fastener is securely kept in the closing position and
prevented from accidental opening even under intensive use,
but the user can open the fastener rapidly and easily at
any time.
The invention is particularly useful in a fluid-tight
fastener, where a small deviation of the slider from the
full-closing position may compromise the fluid-tightness.
Hence, an item fitted with a slide fastener according to
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the invention, such as a sports garment or the like, gives
reliable fluid-tight performance with easy and safe use.
Further advantages and characteristics of the slide
fastener according to the invention will be more evident
from the detailed description and examples provided here
below, with indicative and not limiting purpose.
Brief description of the drawings
Fig. 1 is a perspective view of the top end of a slide
fastener according to an embodiment of the invention.
Fig. 2 is a side view of the fastener of Fig. 1.
Fig. 3 is a side view of the fastener of Fig. 1, with the
puller of the slider in a different position.
Fig. 4 is a top view of the fastener, in the position of
Fig. 3.
Fig. 5 and 6 are cross-sectional views according to lines
V-V and VI-VI of Fig. 4.
Fig. 7 is an enlargement of Fig. S.
Detailed description of a preferred embodiment
Fig. 1 shows a top portion of a slide fastener 1, in
accordance with a preferred embodiment of the invention,
comprising a pair of tapes 2, equipped with teeth 3, a top
stop 4, and a slider 5 with a puller 6. The puller 6 is
connected to the slider 5 by a ring 7.
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The slider 5 is movable in a sliding direction, parallel to
tapes 2, up to a closing position where the slide fastener
1 is fully closed, i.e. all teeth 3 are engaged and the
slider 5 is in contact with the top stop 4. Said closing
position is shown in Fig. 1.
Details of tapes 2 an teeth 3 can be according to known art
and are not discussed in detail. For example, in a fluid-
tight sliding fastener, tapes 2 are made of a textile core
layer fully coated on both sides by a suitable waterproof
layer and teeth 3 are injection-molded on tapes 2. The top
stop 4, in a fluid-tight slide fastener, can also be
injection-molded on tapes 2.
The slider 5 (Fig. 2) substantially comprises upper and
lower blades 8, 9 with lateral flanges 10, 11 on both
sides, and a diamond connecting said upper and lower blades
8, 9. Flanges 10 and 11, in use, act on suitable contact
faces of teeth 3 in order to bring the facing teeth of the
tapes 2 to reciprocal engagement, according to known art.
When the slide fastener 1 is fully closed, i.e. the slider
5 is in the position of Fig. 1, the diamond can be received
in a seat between leg portions 12 of the top stop 4.
The puller 6 can be fitted from the position of normal use,
as seen in Fig. 1 and 2, to a locking position on the top
stop 4, shown in Figs. 3 and 4. In said locking position,
the puller 6 is lying on the top stop 4, substantially
parallel to the sliding direction of the slider 5.
A front wall 20 is integrally formed in the top stop 4,
acting as a stop means against a bottom contact face 30 of
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the puller 6. The wall 20 has a rear surface 32 (Fig. 2)
acting as a stop means against the contact face 30 of the
puller 6, when in position of Figs. 3-4. Opposite to the
surface 32, the wall 20 has a front surface 31 facing the
slider; advantageously, there is a gap between said front
surface 31 and the slider 5 for clearance recovery. The
contact face 30 may be slightly curved and, in this case,
the rear surface 32 of wall 20 is curved accordingly (Fig.
4).
Two toothed elements 22, 23 project upwards from the
central portion of base part 21 of the wall 20, adapted to
mechanically engage the ring 7 in order to "lock" the
puller 6 in the position of Figs. 3-4. Each of said
elements 22 and 23 has an elastically deformable stem
portion projecting upwards from the base 21, and a head
portion defining an undercut recess 22 for receiving the
ring 7 when the puller is in the locking position.
As seen in the cross-sectional view of Figs. 5 and 7, each
of elements 22, 23 has a stem portion 24 projecting upwards
from base part 21 of the wall 20, and carrying a head
portion 25 projecting laterally and outward from the top of
the stem 24, defining inclined surfaces 26 and 27
converging to an edge 28, and the undercut recess 22 below
said edge 28 and between the base 21 and the head 25
itself.
Pressing the ring 7 against faces 26 or 27 has the effect
of bending laterally and inwards the stem portion 24 of the
toothed elements 22 and 23, thus engaging the ring 7 in the
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recess 22 or vice-versa disengaging the same ring 7 and
puller 6 from the locking position.
In the shown embodiment, the top stop 4 also comprises a
pin 40 which is received in a corresponding hole 41 of the
5 puller 6, when the puller 6 is in said locking position.
Said pin 40, received in the hole 41, retains the puller 6
from lateral movement.
In the example, the pin 40 is elliptical and frusto-
conical, with a cross section decreasing from base to top.
10 However, the pin 40 may also be cylindrical in simpler
embodiments.
The invention is open to many variants. In other (not
shown) embodiments, for example, the toothed elements 22,
23 or equivalent locking elements can engage a suitable
seat (e.g. a recess) of the puller, rather than the ring
connecting the puller to the slider. Clearly, the position
of said locking elements can be different according to the
needs and/or the design of the top stop.
The puller 6 may also be shaped in a different manner, for
example with a hole in the bottom part defining a ring
portion connecting the puller with the slider 5.
The retaining element, rather than wall 20, may be realized
in different ways, including a plastic or metal element not
integrally formed with the top stop itself.
In a further variant, the slider 5 may be equipped with a
locking element, adapted to cooperate with another
engagement element provided in the top stop 4, so that when
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the slider 5 reaches the top stop 4, said slider is locked
to the top stop and prevented from sliding away. An
unlocking system may be incorporated in the top stop.
Referring to said further variant, the slider for example
has a first coupling element protruding from the front of
the slider itself, adapted to snap on a second coupling
element or recess of the top stop when the slider reaches
the top stop. Said second coupling element or recess may be
provided e.g. on face 31 or equivalent part of the top stop
4. The top stop has an unlocking button associated to said
second coupling element of the top stop, so that acting on
said button the user can move the second coupling element
to a disengaging position, freeing the slider from the top
stop.
Referring back to embodiment of the figures, the invention
operates as follows.
When closing the slide fastener 1, the user pulls the
slider 5 up to the position of Fig. 1, where all the teeth
3 are mutually engaged and the slider 5 reaches the top
stop 4.
To secure the fastener, the user lowers the pull-tab 6 from
the position of use of Figs. 1-2 to the locked position of
Figs. 3-4. As the ring 7 contacts the upper surfaces 26 of
teeth 22, 23 (Fig. 2), and due to inclination of said
surfaces 26, the stems 24 are deformed until the ring 7 can
overcome the edge 28, and reach the undercut recesses 22.
When the ring 7 is received in said undercut recesses 22
(Fig. 5), it is locked by elements 22, 23. The contact
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between surfaces 30 and 32 prevents the slider 5 from
sliding away from the top stop 4, thus keeping the fastener
1 closed and ensuring fluid-tightness at the region of the
top stop 4. The puller 6 is safely prevented from leaving
the locking position, by lateral outward projections of the
heads 25 of elements 22 and 23, locking the ring 7 as seen
in Figs. 5 and 7. This is sufficient to avoid undesired
unlock due to the use, plying of the fastener, etc. The pin
40 is a further help to maintain the puller 6 in the
correct locking position, preventing the puller from
lateral movement.
The fastener is unlocked by lifting the puller 6, so that
the ring 7 bends the elements 22, 23 pressing against the
contact surfaces 27, until the ring 7 itself reaches the
edge 28 and is freed to the use position of Figs. 1-2
again. Then, the user can open the slide fastener 1 as
usual.
It should be appreciated that the puller 6 is locked and
unlocked manually and in a quick and immediate way by
lowering or, respectively, lifting the puller.
Notwithstanding this, when the puller 6 is locked the
slider 5 is firmly secured on the top stop 4, and
accidental opening of the fastener and/or loss of the
fluid-tightness is prevented in a reliable way.
Of course, a person skilled in the art can bring
modifications and variants to the invention in order to
satisfy specific requirements, all of which are in any case
covered by the scope of protection of the following claims.