OBJECT OF THE INVENTION
[0001] The invention proposed herein applies to sofas fitted with a mechanism that allows
the backrest to be moved relative to the seat by means of a turning movement, thereby
to define three positions therefor: a seated position, a relaxed position and a lying
down position.
[0002] The present invention successfully optimises the functional conditions of this type
of systems by including a mechanism that is structurally extremely simple, its functionality
being limited to a reduced number of parts, the most significant element fitted being
a cam having a special geometry adaptable to the end configuration of the backrest
profile for each different position of the sofa.
BACKGROUND OF THE INVENTION
[0003] The solutions used in mechanisms to articulate sofas or sofa beds are varied and
mostly lie in the integrated arrangement of a set of interrelated parts that define
a functionality associated to a high structural complexity, which results in a larger
number of adjustments and hence maladjustments arising from the continued use of the
mechanism.
[0004] A well-known type of mechanism uses an angular part linked to the framework of the
sofa, arms associated to the sofa backrest profile turning relative thereto, determining
in their displacement the associated movement of the sofa seat profile, thereby allowing
the angular relation between the backrest and the seat to be changed, defining several
positions for the sofa.
[0005] The movement to draw the seat member and fix the various positions of the sofa is
entrusted to a number of intermediate parts which are linked between both elements.
[0006] The complexity derived from using a considerable number of intermediate parts leaves
room for another solution to be proposed, allowing the same function aforesaid to
be achieved with a mechanism that is mechanically much simpler.
DESCRIPTION OF THE INVENTION
[0007] The present invention consists of a reclinable sofa positioning mechanism with which
the problems aforesaid are resolved, being essentially noteworthy due to the inclusion
of a turning cam sliding in contact with the end surface of the backrest profile,
defining the various positions of the sofa by coupling between the perimetric sectors
of said contacting surfaces, a billet being included between the two in order to ensure
a permanent contact between said surfaces.
[0008] The mechanism is fixed to the framework of the sofa by means of a plate, with two
connecting arms articulated thereto that are solidly connected at their other ends
to the backrest profile, the entire assembly linked to such profile being displaced
relative to said plate at the sofa extension stages. The mechanism has a contacting
arm that serves as an abutment for the relaxed position, in which it establishes contact
with one of the connecting arms, making it easier to fix the unit in such position.
[0009] The cam is angular in shape and its articulation to the billet lies at its curved
vertex, with a hole on one side for the insertion of one end of a spring that is associated
to the seat profile and is tensed in the seated and relaxed positions, and provided
on the other side with a curved projection and a stepping on the perimeter, adjustable,
according to the position, to the surface of the end of the backrest profile, its
displacement being defined by the movement of the backrest profile which causes the
cam to turn, sliding in permanent contact with said end salient of the backrest profile.
[0010] The cam is also related to the backrest by means of the billet to which it is linked
at one end by means of a bolt which also associates the cam to the backrest profile,
said billet being arranged above the level of the cam and end contacting surface of
the backrest profile, ensuring contact between the two during displacement between
the seated A and relaxed B positions. The other end of the billet houses the articulation
relative to which the backrest profile and seat profile turn.
[0011] The backrest profile has an indenture-like recess at its end in which the cam projection
is housed in the seated position.
[0012] When the unit is displaced to the relaxed position, the end of the backrest profile
slides until one of its side salients is coupled in the cam stepping, in which position
the cam spring is stretched and the contacting arm abuts against the outer arm connecting
the backrest profile and the framework, the turning movement of the connecting arms
being limited, the unit being thereby fixed in such position.
[0013] The contacting arm is articulated at one end to the seat profile and its other end
is free, an articulation being provided close to the first articulation, to which
a thrust billet is associated that is solidly connected at its other end to the backrest
profile by means of a bolt. The mobility of said thrust billet is conditioned by the
displacement of the backrest profile.
[0014] In the lying down position, the contacting surface of the backrest profile is disengaged
from the cam and the contacting arm is separated from the arm connecting the backrest
profile and the framework plate, the backrest profile lying collinearly with the seat
profile.
DESCRIPTION OF THE DRAWINGS
[0015] In order to provide a fuller description and contribute to the complete understanding
of the features of this invention, a set of drawings is attached to the specification
which, while purely illustrative and not fully comprehensive, shows the following:
[0016] Figure 1.- Is a side view of the sofa positioning mechanism in a seated position.
[0017] Figure 2.- Is a partial side view of the sofa positioning mechanism in a relaxed
position.
[0018] Figure 3.- Is a partial side view of the sofa positioning mechanism in a lying down
position.
PREFERRED EMBODIMENT OF THE INVENTION
[0019] With reference to the figures, it may be seen that the reclinable sofa positioning
mechanism subject of the present invention comprises a seat profile (1) and a backrest
profile (2) articulated at a bolt (3) about which they vary their relative angular
position, a plate (4) being provided as an element to fix the mechanism to the sofa
framework and with respect to which two arms (5) and (6) are articulated, associated
at their other end to the backrest profile (2). The mechanism of the invention allows
the sofa to be fixed in the seated A, relaxed B and lying down C positions, to which
end it is, unlike other types of mechanisms, essentially characterised by consisting
of an assembly comprising a small number of parts which allow the mechanism to be
displaced and fixed in said positions, being primarily noteworthy due to the provision
of a cam (7) the shape of which may be adapted to the contacting end (11) of the backrest
profile (2). More specifically, the cam (7) is angular in shape and is articulated
at a bolt (8) lying on its rounded vertex, which bolt moreover links the cam at such
point of the seat profile (1); said cam (7) includes a hole on one side for the insertion
of a spring (9) that is associated at its other end to the seat profile (1), and a
curved projection and a stepping on its other side, couplable to the contacting surface
(11) of the backrest profile (2) in the different positions of the latter with respect
to the seat profile (1).
[0020] The mechanism includes a billet (10) connected at one end to the backrest profile
(2) and the seat profile (1) by means of the articulation (3), and connected at its
other end to the cam (7) and the seat profile (1) by means of a bolt (8).
[0021] The end surface (11) of the backrest profile (2) has a middle recess in which the
cam (7) projection is housed in the seated A position.
[0022] In the following cam (7) position, after its turning movement, the projection slides
into contact with the end surface (11) of the backrest profile (2), which latter surface
is arranged on the cam (7) stepping, thereby for the relaxed B position to be fixed.
[0023] The mechanism includes a contacting arm (12) serving as an abutment, one of its ends
being fixed to the seat profile (1) by means of an articulation (13) about which it
turns, and its other end being free, its mobility being defined by a thrust billet
(14) linked close to the articulation (13) by means of an articulation (15), its other
end being associated to a bolt (16) about which the arm (6) connecting the backrest
profile (2) to the plate (4) turns.
[0024] In the relaxed position, and in order to avoid sliding between the cam (7) and the
end surface (11) of the backrest profile (2), the contacting arm (12) abuts against
the external connecting arm (5).
[0025] In the lying down C position, the end surface (11) of the backrest profile is no
longer in contact with the cam (7).
1. A reclinable sofa positioning mechanism, of the kind comprising a seat profile and
a backrest profile, being articulated at a bolt about which they vary their relative
angular position, and articulated relative to the framework by means of two connecting
arms associated at their other end to the backrest profile, characterised by the inclusion
of a cam (7), which is angular in shape, articulated at a bolt (8) located at its
rounded vertex, which bolt (8) also links the cam at this point to the seat profile
(1), the cam (7) having a hole on one side for the insertion of a spring (9) whose
other end is associated to the seat profile (1), said cam (7) being provided with
a curved projection and a stepping on its other side, which are couplable to the end
surface (11) of the backrest profile (2) in the various positions of the backrest.
2. A reclinable sofa positioning mechanism, as in the preceding claim, characterised
in that the end surface of the backrest profile (2) has a middle recess where the
cam (7) projection is housed in the seated A position, such projection being slidable
in its turning movement in contact with the end surface (11) of the backrest profile
(2), the latter surface (11) being arranged on the cam (7) stepping in the relaxed
B position, and is no longer in contact with the end surface (11) of the backrest
profile (2) when the cam is in the lying down C position.
3. A reclinable sofa positioning mechanism, as in preceding claims, characterised in
that the mechanism includes a billet (10) connected at one end to the backrest profile
(2) and the seat profile (1) by means of an articulation (3), and connected at its
other end to the cam (7) and the seat profile (1) by means of a bolt (8).
4. A reclinable sofa positioning mechanism, as in preceding claims, characterised in
that the mechanism includes a contacting arm (12), on a plane above that of the billet
(10), serving as an abutment, one of its ends being fixed to the seat profile (1)
by means of an articulation (13) about which it turns, and its other end being free,
its mobility being defined by a thrust billet (14) linked close to the articulation
(13) by means of an articulation (15), its other end being associated to a bolt (16)
about which the arm (6) connecting the backrest profile (2) and the plate (4) turns,
the contacting arm (12) abutting against the outer connecting arm (5) when in the
relaxed position, in order to avoid sliding between the cam (7) and the end surface
(11) of the backrest profile (2).