[0001] The present invention relates to a guiding device for two parts which can move with
respect to each other in opposite directions, particularly for pieces of furniture
or the like.
[0002] Guiding devices meant to allow the movement of two parts which can move with respect
to each other in opposite directions are known in the field of furniture. This is
the case, for example, of pull-out tables in which one table surface is divided into
two portions, which can be moved mutually apart so as to allow to interpose an element
for extending the table surface.
[0003] In order to allow the movement of the two moving parts of pull-out tables of this
kind, devices are currently used which are substantially constituted by a profiled
element meant to be fixed to the supporting structure of the table and inside which
two pulleys with parallel axes are supported; a wire-like element, usually made of
steel, winds around said pulleys. The wire-like element is arranged on a substantially
vertical plane and is connected, by means of its upper portion, to a block which can
slide along the profiled element and is connected to one of the moving parts of the
table surface, while the lower portion of the wire-like element is connected to another
block which is fixed to the other moving part of the surface.
[0004] As a consequence of the connection between the two blocks connected to the wire-like
element, when one moving part of the surface is moved in one direction, the other
moving part shifts in the opposite direction, so as to achieve the mutual spacing
or approach of the two moving parts.
[0005] The two blocks are furthermore generally fixed to suitable sliding guides, which
are coupled to the profiled element by means of a plurality of ball bearings to facilitate
the translatory motion of the moving parts of the table surface.
[0006] These devices entail some drawbacks.
[0007] They are in fact labor-intensive to assembly, particularly as regards the wire-like
element on the pulleys.
[0008] Moreover, the moving parts of the device are exposed and can therefore be touched
by cloths when cleaning the piece of furniture or by other foreign objects which can
get caught in the moving parts, compromising the correct functionality of the device.
[0009] These devices also have limited flexibility as regards their manufacture, particularly
when size changes are required.
[0010] Labor-intensive assembly also significantly affects overall production costs.
[0011] Another drawback is the fact that the ease with which the two moving parts connected
to the blocks can slide can be altered by an incorrect tension of the wire-like element.
[0012] The aim of the present invention is to obviate the above drawbacks, by providing
a guiding device for two parts which can move with respect to each other in opposite
directions, meant particularly for the field of furniture or the like, which can be
assembled very easily and quickly, so as to have low production costs.
[0013] Within the scope of this aim, an object of the present invention is to provide a
device which is highly precise in operation even after a large number of duty cycles.
[0014] Another object of the present invention is to provide a device which is highly reliable
in operation.
[0015] This aim, these objects and others which will become apparent hereinafter are achieved
by a guiding device for two parts which can move with respect to each other in opposite
directions, particularly for pieces of furniture or the like, characterized in that
it comprises at least one guiding profiled element which supports, so that they can
slide along its longitudinal extension, at least two sliding blocks which are associable
with one moving part and with the other moving part respectively, each one of said
two sliding blocks being connected to a rack which is slidingly accommodated in a
longitudinal seat formed in said guiding profiled element; a pinion being supported,
so that it can rotate about its own axis, in an intermediate region of said guiding
profiled element, said pinion meshing, by means of two diametrically opposite regions
thereof, with the racks connected to said sliding blocks.
[0016] Further characteristics and advantages of the present invention will become apparent
from the following detailed description of a guiding device according to the invention,
illustrated only by way of non-limitative example in the accompanying drawings, wherein:
figure 1 is a side elevation view of the device according to the invention, with the
two sliding blocks in the maximum mutual approach position;
figure 2 is a view, similar to figure 1, of the device according to the invention,
with the two sliding blocks in the maximum mutual spacing position;
figure 3 is a partially sectional exploded perspective view of the guiding profiled
element, of the two racks and of a sliding block of the device according to the invention;
figure 4 is an exploded perspective view of a sliding block;
figure 5 is an exploded perspective view of a detail of a longitudinal end of the
guiding profiled element;
figure 6 is a sectional view of the same detail shown in figure 5, in assembled condition;
figure 7 is an enlarged-scale sectional view of figure 1, taken along the plane VII-VII;
figure 8 is an enlarged-scale sectional view of figure 2, taken along the plane VIII-VIII;
figures 9 and 10 are views of the application of the device according to the invention
to a pull-out table, shown respectively in the normal position and in the extended
position.
[0017] With reference to the above figures, the device according to the present invention
comprises at least one guiding profiled element 1 which supports, so that they can
slide along its longitudinal extension, at least two sliding blocks 2 and 3 which
are respectively associable with one moving part 31 and with the other moving part
32 which are to be moved with respect to each other in opposite directions.
[0018] Each one of the two sliding blocks 2 and 3 is connected to a rack, designated by
the reference numerals 4 and 5 respectively, and is slidingly accommodated within
a longitudinal seat 6, 7 formed in the body of the guiding profiled element 1. A pinion
8 is supported, so that it can rotate about its own axis 8a, in an intermediate region
of the extension of the guiding profiled element 1 and simultaneously meshes, by means
of two diametrically opposite regions thereof, with the racks 4 and 5 connected to
the sliding blocks 2 and 3.
[0019] More particularly, the guiding profiled element 1 has a substantially C-shaped transverse
cross-section; in a central position thereof there is provided a central sliding seat
9 for the sliding blocks 2 and 3, which protrude, with a portion 10 thereof meant
to be fixed to one or the other of the moving parts, from the open side of the C-shaped
configuration of the guiding profiled element 1.
[0020] The longitudinal seats 6 and 7, which accommodate the racks 4 and 5, are formed in
the guiding profiled element 1 laterally and on opposite sides with respect to the
central sliding seat 9.
[0021] It should be noted that the guiding profiled element 1 can be constituted by an extruded
profiled element, for example made of light alloy, in which both the central sliding
seat 9 and the longitudinal seats 6 and 7 for the racks are provided directly during
extrusion and without additional machining.
[0022] The racks 4 and 5 can be connected to the respective sliding blocks 2 and 3 by providing,
on the side of the racks that is meant to be directed toward the sliding block to
which the rack is to be connected, pins 4a, 5a which are engaged in seats 11 provided
for this purpose inside the sliding blocks 2 and 3.
[0023] The connection of a sliding block to the corresponding moving part can be provided
by means of a bracket 13, 14 which couples to the protruding part of the corresponding
sliding block, by means of a coupling 10 which is preferably dovetail-shaped.
[0024] The brackets 13, 14 can be fixed to the corresponding sliding blocks 2, 3 by punching
12, as shown in particular in figure 7, thus avoiding the use of screws or of other
more complex fixing elements.
[0025] The guiding profiled element 1 forms, with one of its sides, a sliding surface 15
for the moving parts that are associated with the sliding blocks 2 and 3. Low-friction
balancing means, designated by the reference numeral 20, for the moving parts are
arranged along said side, at least proximate to the longitudinal ends of the guiding
profiled element 1.
[0026] More particularly, the low-friction balancing means comprise a wheel 21 which is
partially accommodated in the guiding profiled element 1 and protrudes therefrom through
a specifically provided opening 22, so as to form a region for the rolling-friction
resting of the lower face of the moving part if the guiding profiled element 1 is
fitted horizontally, as in the case of pull-out tables, as will become apparent hereinafter.
[0027] The wheel 21 is mounted on a clip 23, which can be inserted in the longitudinal seat
6 from a longitudinal end of the guiding profiled element 1 and can be engaged in
a snap-together fashion, by means of a stud 33, in a retention abutment 24 which is
constituted for example by a hole formed in the guiding profiled element 1.
[0028] Stop abutments can be provided proximate to the longitudinal ends of the guiding
profiled element 1, in the central seat 9 or in the longitudinal seats 6 and 7, in
order to delimit the sliding of the sliding blocks 2 and 3. Said stop abutments can
be simply constituted by raised portions, such as punched areas, or by screws or other
abutments to be associated with the guiding profiled element 1.
[0029] Preferably, each moving part 31, 32 can be connected to one or more sliding blocks
associated with a same rack. In the illustrated embodiment, in addition to the sliding
blocks 2 and 3 there are also provided two other sliding blocks, designated by the
reference numerals 2a and 3a respectively, which are connected to one moving part
31 and to the other moving part 32 respectively.
[0030] For the sake of completeness in description, it should be noted that the region of
the guiding profiled element 1 that accommodates the pinion 8 can be covered by means
of a protective plug 30.
[0031] The use of the device according to the present invention in pull-out tables is as
follows.
[0032] Two devices such as the one described above are arranged horizontally, parallel to
each other, and are fixed to the supporting structure of the table. The two moving
parts 31, 32 of the surface of the table are fixed to the bracket 13 of the sliding
blocks 2, 2a and to the bracket 14 of the sliding blocks 3, 3a respectively.
[0033] As a consequence of the connection between the two racks 4 and 5 provided by means
of the pinion 8, by acting on one of the two moving parts the mutual approach or spacing
of the other moving part is achieved.
[0034] It should be noted that the device according to the present invention, despite being
conceived particularly to be used in the production of pull-out tables, can in any
case be used to allow mutual movement between two moving parts of pieces of furniture
in general, or can in any case be used more generally also to produce safety gates,
doors of elevators or for other similar uses which require the possibility to move
one moving part toward or away from another moving part.
[0035] In practice, it has been observed that the device according to the present invention
fully achieves the intended aim and objects, since it is composed of a limited number
of elements which can be assembled very simply and quickly, thus reducing overall
manufacturing costs.
[0036] Another advantage of the device according to the present invention is that it ensures
perfectly smooth sliding of the two moving parts, if they are arranged horizontally,
as in the case of pull-out tables, even if the weight is considerable, by virtue of
the resting with rolling friction ensured by the balancing means proximate to the
longitudinal ends of the guiding profiled elements.
[0037] In practice, the materials employed, as well as the dimensions, may be any according
to requirements and to the state of the art.
[0038] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly, such reference signs do not have any limiting effect
on the interpretation of each element identified by way of example by such reference
signs.
1. A guiding device for two parts which can move with respect to each other in opposite
directions, particularly for pieces of furniture or the like, characterized in that
it comprises at least one guiding profiled element which supports, so that they can
slide along its longitudinal extension, at least two sliding blocks which are associable
with one moving part and with the other moving part respectively, each one of said
two sliding blocks being connected to a rack which is slidingly accommodated in a
longitudinal seat formed in said guiding profiled element; a pinion being supported,
so that it can rotate about its own axis, in an intermediate region of said guiding
profiled element, said pinion meshing, by means of two diametrically opposite regions
thereof, with the racks connected to said sliding blocks.
2. A device according to claim 1, characterized in that said guiding profiled element
has a substantially C-shaped transverse cross-section and is centrally provided with
a central sliding seat for said sliding blocks, which protrude, with a portion thereof
to be fixed to one or the other of the moving parts, from the open side of the C-shaped
cross-section of said guiding profiled element.
3. A device according to claim 2, characterized in that the longitudinal seats that accommodate
said racks are formed in said guiding profiled element laterally, on mutually opposite
sides with respect to said central sliding seat.
4. A device according to claim 1, characterized in that said guiding profiled element
forms, with one of its sides, a sliding surface for said moving parts, low-friction
balancing means for said moving parts being arranged along said side, at least proximate
to longitudinal ends of said guiding profiled element.
5. A device according to claim 4, characterized in that said low-friction balancing means
comprise a wheel which is partially accommodated in said guiding profiled element
and protrudes therefrom through an opening formed in said sliding surface.
6. A device according to claim 5, characterized in that said wheel is supported by a
clip which can be inserted in one of said sliding seats through one of the longitudinal
ends of said guiding profiled element and can be coupled in a snap-together fashion
with a retention abutment provided in said guiding profiled element.
7. A device according to claim 1, characterized in that it comprises stop abutments which
limit the sliding of said sliding blocks along said guiding profiled element.
8. A device according to claim 1, characterized in that said sliding blocks are connected
to one moving part and to the other moving part, respectively, by means of a bracket
which is connected to the corresponding sliding block by means of a dovetail-shaped
coupling.