[0001] The invention refers to a device to be applied to an armchair with a view to allowing
its rotation around a vertical axis while at the same time, if necessary, rocking
similar to the movements of a rocking chair. (rocker).
[0002] The state of the art comprises numerous devices which permit both rotation of an
armchair around the axis normal to the seated plane and its rocking so as to function
as a rocking chair.
[0003] Such devices have a significant importance in the production and sale of leather
armchairs, or those in fabric or other suitable material, since easier to apply and
to use. (rendering application and use easier).
[0004] To this end the above mentioned devices are generally furnished with a fifth wheel
which permits rotation of the armchair around a vertical axis and with a mechanism
placed between the fifth wheel and the same armchair which permits rocking around
the axis normal to that of rotation.
[0005] On the other hand, a medium or large armchair, having a significant weight, requires
a solid and robust/resistant device which permits rotation or rocking while at the
same time, due to its simplicity, may be realised using material lighter in weight
than steel-like materials and therefore requiring minimum maintenance.
[0006] Moreover, such devices must not significantly affect the cost of the same armchair.
[0007] Among the most known, functional, efficient and used devices included in the state
of the art, we quote, as an example, the types of mechanisms which are adaptable to
an armchair in order to obtain rocking and rotation, in which the device permitting
rocking is solid to the upper plate of a fifth wheel and is constituted by two supporting
elements preferably "V-shaped" of a virtual plane on which the base of the armchair
is applied; such supports may solidly carry out angular rotations around the axis
of a tubular element soldered to a frame which in turn is riveted to the upper plate
of the fifth wheel.
[0008] The angular rocking movements of the above mentioned supporting elements are actioned
by two helicoidal springs , below the fifth wheel, on a transversal axis fixed to
the horizontal axis around which rock the said supporting elements.
[0009] The above mentioned devices, though being the most functional , present various drawbacks,
such as:
- interpositioning between the plates of the fifth wheel, functioning as a suspension
support, of a large diameter ball-bearing whose movement, during rotation of the device,
causes noise disturbance due to the impossibility of carrying out an efficient lubrification;
- notable friction of the mechanism which permits rocking of the device during function;
- elastic device built in general of helicoidal springs requiring significant deformation,
also having the function of limiting the range of rocking;
- the necessity, due to the above mentioned deformation of the elastic device, of a
significant thrust to cause rocking of the armchair in line with an individual of
medium-heavy weight and therefore scarcely functional for an individual of minimum
weight;
- significant bulk of the device compared to the support base of a normal-sized armchair
and the significant weight of the same device.
[0010] The aim of the present invention is to eliminate the above mentioned drawbacks.
[0011] At this end the device solves the problem of a greater adaptability of the armchair
to the weight of the individual wanting to cause rocking without application of springs
requiring significant elastic deformation.
[0012] The invention also solves the problem of reducing friction among the parts constituting
the device and the noise of the fifth wheel during its rotation by means of the application
of an anti-friction disc realised in teflon or other suitable material in place of
the ball bearings.
[0013] Another problem solved is the possibility of building a device of reduced dimension.
[0014] The device according to the invention, in a preferred embodiment, is described in
detail with reference to the designs of the tables attached, which illustrate respectively:
figura 1 - an axonometric view of the device;
figura 2 - an enlargement of the device;
figura 3 -- a lateral view of the device in orthogonal projection;
figura 4 - view from above of the plate acting as an interface between the armchair
and the device; figure 5 - the armchair connected to the device, illustrated in greater
size to make its function easier to view;
figure 6 - rocking movements of the device while it functions as a rocking chair;
figure 7- the application of an helical spring to the bracket fastening the flat bars
5 in order to facilitate the rocking of the chair in the case the user is a light
weight person such as a child.
[0015] The device, rocking and rotating on a filth wheel, is applied to a base 9 of the
armchair realised in wood or in other suitable materials (figures 3, 5, 6).
[0016] The device, as illustrated in figure 2, is made up of a fixed lower plate 1 upon
which is positioned an anti-friction disc 2, preferably circular in shape, and upon
this a second rotating upper plate 3 is placed acting as a fifth wheel which rotates
around a rotation pin 4 which, with the interposition of a washer 4.2 at the extremity,
is blocked (into position) by a split-pin 4.1 or nut if threaded.
[0017] The fixed lower plate 1 of the fifth wheel is laterally shaped so as to form two
"C-shaped" profiles 1.4, furnished with holes 1.2 in order to permit insertion of
bolts 1.3 so as to fix the armchair P to the base 9 (figure 3).
[0018] The upper rotating plate 3 is also laterally shaped so as to form two counter-positioned
"C-shaped" borders 3.3 upon each of which a springy curved flat bar 5 , like that
of the base of a rocking chair, is mounted by means of screw bolts 5.3 which, at the
same time connects a metallic bracket 6 'V' shaped with the aim of limiting the range
of the rocking movements with its extremely 6.2. (figure 5).
[0019] The springy curved flat bars 5 are then fixed to a plate 7 furnished with two bended
borders 7.1 and holes 7.2 for their blocking by means of screws 5.4.
[0020] Transversal metal bars 8 are fixed to the plate 7 by means of welds 13, and the metallic
bottom 10 is connected to said metal bars by means of bolts 12 screwed into particular
threaded holes 8.1. The connection between the metallic bottom 10 of the armchair
and the transversal metal bars 8 is achieved by means four wings 11 welded to the
metal bottom 10 and bolts 12: i.e. the metal bottom 10 screwed to the wood base base
of the armchair by bolts 10.1.
[0021] In order to facilitate the rocking movements of the device, caused by individuals
of light weight, the device may be furnished with elastic attachments 6.3 positioned
in corrispondence to the bolts 5.3 that block the brackets 6 (figure 7).
[0022] As may be noted in figure 4, the metallic bottom 10 of the armchair may rotate in
respect to the support base 9 of the same armchair.
1. "Device to obtain rocking and rotating armchairs", including a fifth wheel and rocking
means to be applied on the outer surface of the bottom of the armchairs, characterized in that the fifth wheel includes a collar bearing constituted by an antifriction disc to
be positioned between the fixed lower plate (1) and the rotating upper plate (3) of
the fifth wheel, the anti-friction disc being made of polythene, teflon or other suitable
anti friction and sound-proof materials.
2. Device as claimed in claim 1) characterized by the fact that the rocking means consist of two steel springy curved flat bars (5)
curved in such a way to permit rocking movements similar to those of rocking chairs,
said flat bars being positioned on the borders (3.3) of the rotating upper plate (3)
of the fifth wheel by means of screw bolt (5.3) and a metallic bracket (6), applied
in corrispondence of the symmetry centre V of said flat bars (5), said flat bars (5)
being connected with screw bolts (5.3) to the bended borders (7.1) of plate (7) or
alternatively, with the same screw bolts (5.3), to the extremity of the two metal
bars (7.3) that subsitutes the entire plate (7), orthogonal to longitudinal symmetry
axis of the curved springy flat bars (5).
3. Device as claimed in the previous claims, characterized by metallic brackets (6) having the function to limit the rocking movements of the springy
curved flat bars (5), the brackets (6) being 'V' shaped and being fastened at the
same time, to the curved flat bars (5) on to the border (3.3) of the rotating upper
plate (3),
4. Device as claimed in previous claims, characterized by the presence of two metal bars (8) to connect the device to the outer lower surface
of the metallic bottom (10), of the armchair, the two metal bars (8) being connected
by means of welds (13) to plate (7) or alternatively to the bars (7.3) only
5. Device as claimed in previous claims characterized by the fact that the border (1.4) and (3.3) of the two plates (1) and (3) forming the
fifth wheel, are 'C' shaped to allow respectively the fastening on the base (9) of
the armchair and at the same time to block the springy curved flat bars (5) which
permit the rocking movements of the armchair
6. Device as claimed in previous claims characterized by the fact that the rocking movements of the armchair causes elastic deformation of
the springy curved flat bars (5), said deformation being limited by the inclined borders
(6.2) of the fastening metallic bracket against the plate (7) supporting the bars
(8) or alternatively against the bars (7.3) that substitutes the plate (7) applied
to the outer surface of the bottom of the armchair.
7. Device as claimed in previous claims characterized by further application of springs (6.3) acting as elastic supports concentrical to the
screw bolt (5.3) which fasten the bracket (6) to the springy curved flat bars (5),
to facilitate the movements of the armchair in the case of use of the armchair by
a light weight person or child