Note: Descriptions are shown in the official language in which they were submitted.
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A device for adjusting and clamping the toothed strap of a
fastening for sports footwear
DESCRIPTION
The present invention relates, in general, to a
fastening designed particularly for ski boots, skates and
similar sports footwear.
In particular, the present invention relates to a device
for adjusting and clamping the strap of a fastening of the
aforementioned type, according to the preamble to main claim
No. 1.
The main object of the present invention is to provide
a device for adjusting/clamping the toothed strap of a
fastening of the type in question having structural
characteristics which make it particularly compact so that it
occupies little space on the shell of a ski boot, is easy to
grip, and is equally easy for the user to manipulate, as well
as functional characteristics such as to ensure fine
adjustment of the fastening tension, even under load, as well
as very reliable clamping of the strap, and hence of the
fastening, at the desired tensioning value.
These objects and others which will become clearer from
the following description are achieved by a device for
adjusting/clamping the strap of a fastening of the type in
question which has the characteristics defined precisely in
the following claims.
The characteristics and advantages of the invention will
become clearer from the detailed description of an embodiment
of an adjustment/clamping device according to the invention,
given with reference to the appended drawings, provided by
way of non-limiting example, in which:
- Figure 1 is a side elevational view of an adjus-
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tment/clamping device according to the invention;
- Figure 2 shows the device of Figure 1 in plan;
- Figure 3 shows the device of Figure 1 in longitudinal
section;
- Figures 4, 5, 6, and 7 show, on a reduced scale, some
details of the device of the invention illustrated in the
preceding drawings;
- Figure 8 shows a variant of the adjustment/clamping device
of Figure 1, in longitudinal section;
- Figures 9, 10 and 11 show the device of Figure 3 in
longitudinal section, in various operative conditions;
- Figure 12 is a side elevational view of a further variant
of the adjustment and clamping device of Figure l;
- Figure 13 is a side elevational view of a third variant of
the device of the invention;
- Figure 14 shows the device of Figure 13 in plan;
- Figure 15 shows the device of Figure 13 in longitudinal
section;
- Figures 16 and 17 show the device of Figure 13 in various
operative conditions;
- Figure 18 is a side elevational view of a further variant
of the device of Figure l;
- Figure 19 shows the device of Figure 18 in longitudinal
section.
With reference to the aforementioned drawings, a
tension-adjustment and clamping device for a toothed strap 2
or rack of a fastening for ski boots and similar sports
footwear, generally of the type having an upper moulded from
plastics material, is generally indicated 1.
The device 1 comprises a base 3 with shoulders 4 and 5
on opposite sides and is intended to be fixed to a flap of
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the upper by conventional means, not shown, for example, one
or more rivets which engage respective holes 3a in the base
3.
A pin 6 is fixed to the shoulders 4, 5 and a first lever
7 is pivotable thereon.
This lever 7 (Figures 4 and 5) has a substantially fork-
like structure with identical, parallel arms 7b, 7c extending
from an operating end (or grip) 7a of the lever.
A slot-like hole 8, by means of which the lever 7 is
mounted for pivoting and sliding on the pin 6, extends
through the arms 7b, 7c, close to their free ends. Owing to
this engagement, the lever 7 is pivotable on the base 3 with
a movable fulcrum (6-8).
Respective seats 9, 10 (Figures 2 and 5) are formed in
the arms 7b, 7c of the lever 7 for housing springs 11, 12.
The latter bear at one end on the bases of the seats 9,
10 and at the other end on the pin 6. In normal conditions
(Figure 3), the springs 11, 12 consequently keep the lever 7
in the position in which the pin 6 is engaged by the ends of
the slot-like hole 8 closest to the free ends of the arms 7b,
7c of the lever 7.
In an intermediate position, the lever 7 has a pin 17
extending parallel to the slot-like hole 8 and projecting
from opposite sides of the lever. This pin 17 is engaged
for rotating and sliding (Figures 1 and 2) in slot-like holes
18, 19 formed in the opposed shoulders 4, 5 of the base 3.
The maximum extent of the angular movements of the lever 7
about the pin 6 depends on the length of the slot-like holes
18, 19 as well as on the movement permitted by the slot-like
hole 8.
A passageway 20 for the toothed strap 2 is defined
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between the lever 7 and the base 3.
The lever 7 also has, in its wall facing the base 3, a
pair of teeth 21, 21 for engaging the teeth of the strap 2,
with which they are substantially equidirectional, so as to
constitute the pawls of a ratchet mechanism for stopping the
strap, as will become clear from the following description.
A second lever 22, the operating end or grip 22a of
which has a semicircular profile in plan, is positioned
between the arms 7b, 7c of the lever 7, extending outwardly
at the free ends of the arms 7b, 7c.
The lever 22 is pivotable on a pin 23 supported by the
arms 7b, 7c in a position outside the shoulders 4, 5 of the
base 3.
A spring 24 wound on the pin 23 has one end bearing
underneath one of the arms 7b, 7c and the other end bearing
under an appendage 25 projecting from the front of the lever
22 and having a triangular profile for engaging the toothed
strap 2 like a pawl.
The lever 22 and the respective pawl 25 constitute an
"advancing ratchet mechanism" for the toothed strap 2, as
will become clear from the following description.
According to a preferred embodiment, the pawl 25 is
structurally independent of the respective lever 22.
In this embodiment (Figures 3, 6 and 7), the lever 22
has a curved end portion 26 inclined towards the base 3, and
the pawl 25 has a substantially handle-like portion 25a
mounted rotatably on the pin 23. The spring 24 acts on the
pawl 25, urging it against the inclined portion 26 of the
lever 22 from below.
When the action of the spring 24 on the pawl 25 is
predominant, the pawl 25 and the lever 22 essentially
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constitute a single unit.
Figure 8 shows a variant of the invention in which the
ratchet mechanism for advancing the strap 2 is constituted by
a lever 122 defining an integral pawl 125 projecting from its
front end. The spring 24 acts on the lever 122.
Figure 12 shows a further variant of the invention in
which the ratchet mechanism for advancing the strap 2 is
constituted by a lever 222 defining an integral pawl 225 with
three teeth 225a, 225b, 225c, projecting from the front end
of the lever.
The adjustment/clamping device of the invention operates
as follows.
In an initial condition of the device (Figure 1), the
toothed strap 2 is inserted through the passageway 20 defined
by the levers 7, 22, by the base 3, and by the respective
shoulders 4, 5.
As it passes through the passageway, the pawls 21 of the
lever 7 (the stopping ratchet mechanism) do not obstruct the
advance of the strap, even though they interfere with the
teeth thereof, since these teeth and the aforesaid pawls are
equidirectional and the lever 7 is free to move angularly
about the pin 6.
When it has passed beyond the base 3, the strap 2 is
gripped manually by the user and "pulled" as far as possible
to achieve so-called fastening with rough tensioning.
When the strap 2 is released, it is clamped by the
engagement of the pawls 21, 21 in the teeth of the strap.
At this point, the user can carry out fine adjustment of
the degree of tensioning of the strap under load.
For this purpose (Figures 9 and 10) the ratchet
mechanism (22-25) for advancing the strap is operated. The
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lever 22 is gripped and is moved angularly about the pin 23
(anticlockwise with reference to the drawings) so that,
initially, the pawl 25 is engaged between the teeth of the
strap 2 (Figure 9) and, subsequently, upon completion of the
aforesaid angular movement, the strap is advanced through the
passageway 20. As already stated, this advance is not
obstructed by the stopping ratchet mechanism, the pawls 21 of
which "skip" over tooth after tooth as long as the advance
continues, that is, until the angular (anticlockwise)
movement of the lever 22 is completed.
When the maximum possible angular movement has been
reached, the lever 22 is lowered again (Figure 10).
Initially, the movement of the lever 22 is not followed by
the respective pawl 25, which remains engaged between the
teeth of the strap 2 in opposition to the spring 24. I n
this situation, the pawls 21 of the stopping ratchet
mechanism engage the teeth of the strap 2 positively with a
short delay after the lever 22 starts to be lowered, clamping
it in the position reached. During the aforesaid short
delay, the strap 2 performs a corresponding small rearward
movement relative to the passageway 20, thus releasing the
pawl 25 which is urged by the spring 24 back to its position
against the curved appendage 26 of the lever 22, becoming a
single unit therewith.
The desired degree of tensioning of the strap 2 is
achieved by a number of angular movements of the lever 22, as
described above.
To open the device of the invention quickly, allowing
the strap to be withdrawn from the passageway 20 and thus
"unfastening" the sports footwear, it suffices to move the
lever 7 angularly about its movable fulcrum (pin 6/slot-like
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hole 8) in order to move the stopping and advancing ratchet
mechanisms away from the base 3 simultaneously.
This angular movement of the lever 7 is permitted by the
movement of the pin 6 along the respective slot~like hole 8
in opposition to the springs 11, 12, and by the sliding of
the pin 17 in the slot-like holes 18 and 19.
With reference to Figures 13 to 17, a device for
adjusting and clamping the strap 2 according to a third
variant of the invention is generally indicated 300.
Details similar to those of the preceding embodiments
are indicated by the same reference numerals.
The device 300 comprises a base 303 with shoulders 304,
305 on opposite sides and is intended to be fixed to a flap
of the upper by means of rivets or similar means, not shown,
which engage respective holes 303a in the base 303.
The device 300 differs from the preceding embodiments
essentially in that the first lever 307 of the stopping
ratchet mechanism is formed in two structurally independent
portions, indicated 307a, 307b, respectively.
The first portion 307a has a substantially fork-like
structure with identical, parallel arms 308a, 308b extending
from an operating end (or grip) 309 of the lever.
A hole 310 extends through both of the arms 308a, 308b
close to their free ends. The hole 310 houses a pin 311 by
means of which the portion 307a is articulated to the base
303. The pin 310 in turn is engaged for rotating and sliding
in slot-like holes 318a, 318b formed in the opposed shoulders
304, 305 of the base 303. Owing to this engagement, the
portion 307a of the lever is pivotable on the base 303 with
a movable fulcrum (311-318a, 318b).
The second portion 307b of the lever 307 has a
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passageway 320 for housing a pin 321 by means of which the
portion 307b is articulated to the first portion 307a. The
pin 321 is also engaged for sliding in slots 321a, 321b
formed in the opposed shoulders 304, 305 of the base 303,
respectively.
Each slot 321a, 321b comprises a first portion and a
second portion, indicated 322, 323, respectively, one forming
an extension of the other. The first portion 322 is
substantially straight or curved but in any case permits free
pivoting of the lever 307 about the axis of the pin 311,
possibly facilitated by small translational movements of the
pin 311 in the corresponding slot-like holes 318a, 318b.
The second portion 323 is oriented away from the pin 311
to constitute a kind of recess for housing the pin 321, as
will be explained further below.
The second portion 307b of the lever 307 also has a
tooth 324 in its wall facing the base 303 for engaging the
homologous teeth of the strap 2 so as to constitute a pawl
for stopping the strap.
An appendage 325 projecting from the second lever
portion 307b is normally urged into abutment with a
corresponding surface 326 of the first lever portion 307a by
means of a spring 327 wound around the pin 311.
The spring 327 has one end restrained slidably in one of
the shoulders 304, 305 and the other end housed in a recess
329 formed in the second portion 307b of.the lever 307,
beneath the appendage 325.
The ratchet mechanism for advancing the strap 2 is
constituted by a second lever 330 defining an integral pawl
331 with two teeth 331a, 331b projecting from the front end
of the lever.
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The second lever 330 is pivotable on a pin 332 supported
by the arms 308a, 308b of the lever 307 in a position outside
the shoulders 304, 305 of the base 303. The lever 330 has
an operating end or grip 330a having an essentially semi-
circular profile in plan, extending outwardly at the free
ends of the arms 308a, 308b.
A spring 334 wound around the pin 332 has one end
bearing beneath one of the arms 308a, 308b and the other end
bearing beneath the pawl 331.
The device 300 of this third variant of the invention
operates as follows.
With regard to the adjustment of the tensioning of the
strap 2, the operation is exactly the same as that of the
preceding embodiments.
In an initial condition of the device (Figure 13), the
toothed strap 2 is inserted through the passageway 20 defined
by the levers 307, 330, by the base 303, and by the
respective shoulders 304, 305.
As the strap passes through the passageway, the pawl 324
of the lever 307 (the stopping ratchet mechanism) does not
obstruct the advance of the strap, even though it interferes
with the teeth thereof, since these teeth and the pawl are
equidirectional and the portion 307b of the lever 307 is free
to move angularly about the pin 321 (anticlockwise).
When it has passed beyond the base 303, the strap 2 is
gripped manually by the user and "pulled" as far as possible
to achieve so-called fastening with rough tensioning.
When the strap 2 is released, it is clamped by the
engagement of the pawl 324 in the teeth of the strap.
At this point, the user can carry out fine adjustment of
the degree of tensioning of the strap under load.
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For this purpose ~Figure 16), the ratchet mechanism
(330-331) for advancing the strap is operated. The lever 330
is gripped and is moved angularly about the pin 332
(anticlockwise with reference to the drawings) so that,
initially, the pawl 331 is engaged between the teeth of the
strap 2 (Figure 16) and, subsequently, upon completion of the
aforesaid angular movement, the strap is advanced through the
passageway 20. As already stated, this advance is not
obstructed by the stopping ratchet mechanism, the pawl 324 of
which "skips" over tooth after tooth as long as this advance
continues, that is, until the angular (anticlockwise)
movement of the lever 330 is completed.
When the maximum possible angular movement has been
reached, the lever 330 is lowered again (Figure 15). The
desired degree of tensioning of the strap 2 is achieved by a
number of angular movements of the lever 330, as described
above.
It will be noted that, in the position of Figure 15, in
which the strap 2 is clamped, the lever 307 is moved towards
the left (as seen in Figure 15) with the pin 311 in abutment
with the corresponding end of the slot-like hole 318a, 318b
as a result of the load exerted on the tooth 324 by the strap
2 under tension. The pin 321 is consequently housed in the
recess 323 of the corresponding slot 321a, 321b thus
preventing the lever 307 from rotating about the axis of the
pin 311 and consequently releasing the tooth 324 from the
teeth of the strap 2.
To open the device, allowing the strap to be withdrawn
from the passageway 20 and thus "unfastening" the footwear,
it suffices to move the portion 307a of the lever 307
angularly about the respective movable fulcrum (pin 311/slot-
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like hole 318a, 318b) to move the stopping and advancing
ratchet mechanisms away from the base 303 simultaneously.
Upon a first operation of the lever 307 (clockwise with
reference to Figure 15), the pins 311, 321 are guided in a
rotational-translational movement by the second portion of
the slot 323 and by the slot-like hole 318a, 318b,
respectively. When the pin 321 has passed over the point of
the connection between the first and second slot portions
322, 323, it is guided by the first slot portion 322 with
consequent pivoting of the lever 307 about the axis of the
pin 311. The pin 311 is kept close to the end of the slot-
like hole 318a, 318b farthest from the slot 321a, 321b (the
right-hand abutment). The tooth 324 is completely disengaged
from the strap 2 (Figure 17) as a result of this angular
movement of the lever 307. The shape and arrangement of the
slots 321a, 321b and of the slot-like holes 318a, 318b is
therefore selected in a manner such that, at least in a
portion of the lifting travel, the lever 307 is guided in a
purely rotational movement so as advantageously to reduce the
frictional forces which, particularly when there is mud or
earth on the fastening, may compromise correct operation of
the device.
Figures 18 and 19 show a further variant of the device
of Figure 1, generally indicated 400. The device 400
differs from the device 100 in that the first lever 7 of the
stopping ratchet mechanism is formed in two structurally
independent portions 407a, 407b.
The first portion 407a is mounted for pivoting and
sliding on the pin 6 with a movable fulcrum (6-8).
The second portion 407b is articulated to the first
portion 407a about the pin 17. It has a tooth 421 for
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engaging the homologous teeth of the strap 2.
An appendage 425 projecting from the second lever
portion 407b is normally urged into abutment with a
corresponding surface 426 of the first lever portion by means
of a spring 427 wound around the pin 17.
The second lever 22 of the stopping ratchet mechanism
differs from the device 1 in that it comprises a pawl 428
defined integrally therewith, with two teeth 428a, 428b
projecting from the front end of the lever.
The operation of the device 400 is exactly the same as
that of the device 1 described above.
The invention thus devised may undergo variations and
modifications all falling within the scope of the inventive
concept as defined by the following claims.
