OBJECT OF THE INVENTION
This invention relates to a compact transverse hoist for blinds meant
to be installed in the narrow cavity defined by the window frame with the masonry,
with a front opening for the handle used to raise the blinds.
This hoist is characterised by a special configuration that optimises
the space inside the hoist so that a height difference can be determined between
the case segment corresponding to the winding and the case segment corresponding
to the main conical gear, so that the presence of a window is enough to thread the
cable without having to open the cover.
Likewise, the invention is characterised by a special configuration
of the shaft supporting the main conical gear, this gear being joined only to a
part of the case so that high forces will not tend to open the case, as when using
bushings trapped between the two parts of the case.
BACKGROUND OF THE INVENTION
Transverse hoists for blinds are known such as that described in the
Utility Model with publication number ES1032899U, consisting of two pairs of gears,
a straight pair and a conical pair, installed in the window frame.
This hoist improves on the known state of the art as described in
its background section, which cites as first antecedents the mechanisms used to
raise the side windows of automobiles.
In these mechanisms, the structure is limited by the need for installation
in a narrow space of the door front panel, such that the gears of these mechanisms
are frontally disposed on a single plane perpendicular to the actuation handle shaft.
In the Utility Model cited, the complexity is increased as the actuation
handle shaft is frontal, not perpendicular to the plane of the gears. In this specific
case a pair of conical gears are used, with the limitation imposed by establishing
an oblique gearing line. The inclination of the gearing line imposes a greater width
of the hoist, so that if the design is not ideal the thickness of the hoist can
be greater that that allowed by the span of the window frame in which it is installed.
The design employed uses a considerably flattened main conical gear
that engages the driving pinion, which is directly connected to the input handle.
The configuration is such that the driving pinion shaft crosses above the main conical
gear until it reaches the opposite side. In this opposite side it enters a bushing,
which is trapped at the mid line between the two halves of the case.
In addition, in this Utility Model it is not possible to thread the
cable except by opening the case to access the winding spool.
Also known is another kinematic arrangement as described in Spanish
Utility Model with publication number ES1036147U. This Utility Model describes a
transversally actuated embedded collecting hoist for blinds in which the handle
acts directly on an endless screw to replace the first pair of conical gears.
In this case it is not possible to reduce the space required by the
screw diameter, so that the screw must at least reach the gearing area.
In the Utility Model, the end of the endless screw opposite the handle
entrance is housed in an orifice made in the case near its mid line.
The present invention establishes a new internal design of the gears
and its supports that allows a more compact design resulting in a narrower and sturdier
hoist that allows threading the cable without opening the two parts of the case.
DESCRIPTION OF THE INVENTION
This invention relates to a compact transverse hoist for blinds that
operates from a side housed in the space left between the window frame and the masonry.
The hoist consists of at least two pairs of gears, a first pair of
conical gears and a second pair of straight gears. The pair of conical gears corresponds
to the driving pinion and the gear referred to herein as the main conical gear.
The second pair of gears is that established between a toothing determined in the
lower plane with a greater diameter that the main conical gear and the toothing
determined in one of the faces of the cable collection spool.
At least two pairs of gears have been specified as it is possible
to interpose an additional simple or double gear between the cable collection gear
and the gear determined by the toothing of the lower plane.
Interposing a simple gear allows a better access from one toothing
to the other when the distance between the shafts is large. The width of the cable
collection spool will not be decreased and its sense of rotation will change, a
fact that is scarcely or not at all relevant as regards its mode of operation.
To also modify the multiplication ratio, a double gear will be interposed.
In this case the increased thickness of this gear will limit the winding capacity
of the cable collection spool.
In any case, the presence or absence of this simple or double wheel
will not modify the invention, which consists of a configuration that allows threading
the hoist without having to open it.
The case is basically flat, with a small thickness to allow housing
it in the space left between the window frame profile and the masonry. This profile
has a front orifice that provides access to the hoist, through which enters the
actuation handle. For this reason, the hoist is provided with a first pair of conical
gears to change the direction of the rotation shaft of the front opening to the
direction of the rotation shaft of the cable collection spool, whose axis is perpendicular
to the main plane of the case.
The shape of the case is in accordance with the two main wheels, those
constituted by the cable collection spool and by the main conical wheel; both are
engaged by the straight gears. This configuration defines a height difference that
is the main basis of the invention, as it will allow the presence of a second window
and other details for threading the cable. Similarly, also belonging to this invention
are the technical solutions used inside the hoist to obtain a compact design that
allows the existence of this height difference.
Unlike the method used to attach the main conical wheel and the driving
pinion in the Utility Model with publication number ES 1 032899U cited in the background,
in the configuration object of this invention the main conical wheel is held by
a turret that rises from the part of the case corresponding to its base.
This turret does not pass through, nor must it necessarily rest on
the other half of the case. Instead, it ends at an orifice with a lateral recess
that acts as a support bridge for the end of the driving pinion.
Optionally, the top end of the turret can rest on an orifice or a
recess made in the top part of the case that acts as a cover.
This technical solution allows a reconfiguration of the case cover
opposite the base of the turret and an optimisation of the space, as the driving
pinion does not cross as far as the opposite side of the case, instead resting on
the support bridge of the turret, which acts as the shaft of the main conical wheel.
Although the end of the pinion shaft rests on an orifice with a lateral
recess, it is possible to have only a recess without a through orifice, providing
a sturdier support that also leads to smaller tolerances.
With the turret joined only to one part of the case, the great loads
to which the driving pinion is subjected only affect this part of the case, not
bushings trapped between the two halves of the case. As a result, these loads do
not tend to separate the two halves and offer a greater mechanical stability and
stiffness to the moving components.
Another important aspect relates to the tolerances of the position
of the pinion and the intermediate wheel that includes the conical and straight
toothings. The invention uses the shaft for the intermediate wheel as a turret,
prolonging it so that it holds the end of the pinion shaft. The fact that the two
conical gears share the same support ensures their correct relative position in
view of the large efforts applied by the handle. The result is a gear that prevents
wear or even destruction of the two toothings.
In addition to these advantages related to strength and position tolerance,
as the driving pinion shaft does not cross to the other side, a free space is determined
above the main conical wheel that allows the second part of the case that acts as
a cover to be closer to the mechanism, defining an external height difference.
This height difference allows opening a window that provides access
to the cable collection spool on the side opposite the cable feeding window.
The cable can be threaded between these windows without having to
open the case.
To perform this threading, the hoist handle is turned until two orifices
of the inner cylinder of the spool in which the cable is wound is approximately
aligned with the feeding windows and the second opposite window that is present
due to the height difference.
In this position, the cable is introduced through the cable outlet
window until it crosses the inner spool window, and lastly the cable comes out of
the second window present due to the height difference.
When the cable end is out, a knot is made in it so that it can enter
through the last window but not through the spool window, as the latter window is
In this way the cable is joined to the spool and is ready for winding,
without requiring to open the hoist case.
The second window present due to the height difference can optionally
be covered by a lid or by a groove that conveniently determines an outlet at a more
distant part of the spool, for example covering the area of the height difference
with a second surface.
Lastly, the same shaft of the driving pinion has a retention element
that in addition to the bearings includes the spring that actually performs the
retention. This retention element is placed at the part nearest the handle entrance
and is housed in a strong seat of the same part of the case from which rises the
supporting turret for the main conical wheel.
Also the object of the invention is the optional inclusion of a window
in the opposite case part that allows the retention element to exit, given the diameter
determined by the inner spring, to reduce even more the distance between the two
planes that define the width of the assembly, resulting in a more compact design.
This configuration requires the seat of the retention element to have
lateral attachment means in which it is inserted and fixed.
DESCRIPTION OF THE DRAWINGS
This descriptive memory is completed by a set of drawings meant to
illustrate the preferred example and not limiting the invention in any way.
Figure 1 shows an exploded perspective view of the transversal hoist
according to a first embodiment of the invention.
Figure 2 shows a perspective view of the same embodiment of the invention
with the parts installed in place and with the upper case part that acts as a cover
removed. This upper case part is not shown in this figure.
Figure 3 shows a perspective view of a second embodiment of the invention
, with the top part of the case removed and shown above the rest of the assembly
to reveal the inside of the transversal hoist.
Figures 4A, 4B and 4C establish a sequence of the process for threading
and attachment the cable to the winding spool. Each figure shows two views: a plan
view of the spool and a perspective of the hoist showing the cable in spite of its
PREFERRED EMBODIMENTS OF THE INVENTION
This invention consists of a compact transversal hoist for blinds
specifically conceived to be housed in the space between the window frame and the
This transverse hoist allows threading the cable without removing
the case part that acts as a cover due to a compact design. The same compact design
facilitates housing in even smaller spaces that those mentioned in the state of
In all the examples of embodiment the cable that enters the hoist
does so through a window placed above the position of the installed hoist.
As the invention is mainly centred on configuration details associated
to a second window placed opposite the cable inlet window, the most suitable position
for a graphical representation of the hoist is a prone position, as it is shown
in each of the figures.
With this position selected for describing the various elements that
compose the invention, hereinafter positional references such as upper, lower, lateral,
etc. shall refer to the figures, not to the position adopted by the hoist when it
First example of embodiment of the invention
Figure 1 shows a first embodiment of the invention in an exploded
perspective view, the part constituting the hoist located between the two parts
of the case: the lower part (1) meant to house all of the hoist parts and the upper
part (2) that acts as a cover.
The lower part (1) of the case has a body essentially consisting of
a base and protection walls configured to hug two intersecting bodies with circular
outlines. This shape is adapted to the two larger bodies: the spool (3) for winding
the cable (7) (represented only in figures 4) and the wheel (6) with the main conical
One of the greater walls of the lower part (1) of the case, externally
straight, is prolonged in two fins (1.1) for attaching the assembly.
The actuation handle enters through this wall. The shaft of this handle
is aligned with the drive pinion (5) that is joined to a retention body (5) that
specifically includes the bearing(s) and the inner retention spring.
The retention body (4) is externally comprised of a plate (4.1) meant
to be housed in a recess (1.4) for its attachment. The attachment is completed by
several arch-shaped seats (1.5) provided in the lower part (1) of the case.
The attachment is ensured by the upper part (2) of the case that rests
above the retention body (4). In this embodiment of the invention a window (2.1)
is included in the upper part (1) of the case to reduce the space required to house
the retention body (4).
The shaft of the drive pinion (5) is prolonged in a small external
segment (5.1) meant to ensure the axial alignment of the pinion (5).
Under the drive pinion (5) is a wheel (6) that incorporates in its
central area a conical gear (6.1) meant to engage the pinion (5), and on its perimeter
a straight gear (6.2) to drive the spool (3) for winding the cable (7). The toothed
wheel of the spool is under the lower face, so that it cannot be seen in the figures.
The spool (3) rests on a circular flange (1.2) above the lower part
(1) of the case that acts as a rotation shaft, in turn engaging another flange (2.1)
placed opposite it at a lower height on the upper part (2) of the case.
The main wheel (6) also has a large orifice (6.3) in its centre that
allows passage of a turret (1.3) joined to the lower part (1) of the case.
This turret (1.3) has two functions: acting as a rotation shaft for
the doubly-toothed conical and straight wheel (6); and supporting the end segment
(5.1) of the shaft of the pinion (5). The turret (1.3) can also incorporate a bushing,
not shown in the figure, to receive the end of the shaft of the pinion (5).
The support is established by passing the end segment (5.1) of the
shaft of the pinion (5) through a bridge (1.3.1) configured on the end of the turret
Turning the handle will drive the pinion (5), which in turn will engage
the main conical gear (6.1) of the lower wheel (6), driving it. As the wheel (6)
engages the straight gear (6.2) disposed peripherally on the spool (3), the latter
will turn and wind or unwind the cable (7) depending on the direction of rotation.
For the sake of clarity and simplicity of the description, none of
the examples of embodiment of the invention incorporate an additional wheel interposed
between the straight peripheral gear (6.2) of the wheel (6) with its shaft in the
turret (1.3) and the spool (3), which does not mean that this is not considered
in the invention.
In this preferred embodiment, the spool (3) has two pairs of windows
(3.1) in its inner central cylindrical surface to allow threading with two different
orientations, where the windows of each pair are placed diametrically opposite each
The upper part (2) of the case closes the entire assembly, protecting
the mechanism and attaching the various parts by its supporting function.
As additional details, in addition to the window (2.2) that allows
housing the upper part of the retention body (4) another window (2.6) is provided
to allow a greater diameter of the driving pinion (5).
A third window (2.5) in the upper part (2) of the case houses the
upper end of the turret (1.3), reducing its bending capacity, so that the stiffness
of the assembly is increased. Unlike the case when the shaft of the pinion (5) is
housed in a bushing held between the two parts (1, 2) of the case in which the gearing
forces tend to separate the parts, the window (2.5) only absorbs the lateral loads
due to the bending of the turret (1.3) and no separation loads between the case
parts (1, 2).
The main advantage of this configuration is not only the sturdiness
and small space required by this design, but that it allows establishing a height
difference (2.3) that allows the existence of a window (2.4) for accessing the spool
(3) at a point opposite the inlet window for the cable (7).
The height difference (2.3) mainly spans the area corresponding to
the main intermediate wheel (6) opposite the area occupied by the pinion (5), as
there are no internal parts that occupy space and the shaft of the pinion (5) is
not prolonged beyond the turret (1.3).
The window (2.4) will allow threading the cable (7) without having
to open the upper part (2) of the case.
Figure 1 shows the notches (1.6, 2.7) respectively made in the lower
part (1) and upper part (2) of the case that define the inlet window for the cable
(7). Figure 4 shows a threading sequence for the cable (7).
The position of the window (2.4) present in the height difference
(2.3) of the upper part (2) of the case, being opposite the inlet window for the
cable (7), allows aligning these two windows and the windows (3.1) of the spool
(3), thereby allowing a cable (7) to pass.
After the cable (7) has crossed the spool (3) and exited through the
window (2.4) of the height difference, a knot (7.1) is made in it. The size of the
spool windows (3.1) is such that they allow the cable (7) to pass but not the knotted
cable (7). In turn, the window (2.4) of the height difference (2.3) allows the cable
(7) to pass whether with or without a knot (7.1), so that after a knot is made in
it, it can be introduced in the hoist again.
When the cable (7) is inside the hoist the know (7.1) will prevent
it from exiting through the spool (3), thereby completing the hoist threading operation.
As the windows (3.1) of the spool (3) have different sizes, placing
the larger window (3.1) on the side of the window (2.4) of the height difference
(2.3) will mean that after threading the knot (7.1) will enter as far as the inside
of the central cylinder of the spool (3), as shown in figure 4C.
The step determined by the height difference (2.3) can be established
in several ways, or can even be covered by a second surface that prolongs the exit
of the cable (7) at a farther position of the inlet window for the cable (7). Any
of these situations are considered to be within the scope of the same invention,
as this invention consists of an efficient design of the space that allows the presence
of a window (2.4) opposite the inlet window for the cable (7) due to the existence
of a height different (2.3).
Second example of embodiment of the invention
Figure 3 shows a second example of embodiment in which the design
of the support turret (1.3) has been changed.
In this example of embodiment, the turret (1.3) does not have a bridge
(1.3.1) that defines a through orifice that houses the end segment (5.1) of the
shaft of the pinion (5). Instead, the turret (1.3) is prolonged in an approximately
cylindrical shape to its upper end, with a blind lateral recess in which enters
the end segment (5.1) of the shaft of the pinion (5).
This configuration prevents axial displacements of the shaft of the
pinion (5), and more importantly establishes a stronger attachment at a point in
which the demands resulting from the handle torque and the engagement of the pinion
(5) are among the greatest in the hoist.
The window (2.5) in which enters the end of the support turret (1.3)
has a shape adapted to this new configuration, so that it is somewhat larger due
to the greater diameter of the end of the turret (1.3).
The essence of this invention is not affected by variations of the
materials, shape, size and arrangement of the component elements, described in a
non-limiting manner that should allow its reproduction by an expert.