Technical field
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The present invention may generally be applied in the field of indoor and outdoor
furniture and particularly relates to an adjustment device for reclining chairs or the
like and a method of making and mounting same, as well as to a chair
incorporating such device.
Background art
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A number of devices are known for adjusting the inclination of the backrest of
chairs, armchairs and lounge chairs. One type of such devices provides the use of
two armrests linked to the movable backrest of the chair, and having a plurality of
equal recesses aligned along their underside. A forward or backward motion of the
armrests causes the movable back to rotate. Therefore, by simply selectively
locking the armrest position relative to the supporting legs of the chair, the
backrest can be set in the desired position.
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DE-A-3707804 and ES-A-252097U disclose two arrangements for locking the
movable backrest in a desired position. To this end, both arrangements include a
pair of locking members integral with the supporting legs of the chair. Each locking
member is made in such a manner as to allow engagement thereof in one of the
recesses provided on the underside of each armrest, thereby selectively locking
the backrest inclination. The backrest position may be changed by simply raising
both armrests, releasing the locking members from the corresponding recesses
and lowering the armrests, thereby engaging each locking member in a second
recess.
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An apparent limit of such arrangements is that each locking member has a
projecting upper portion with an essentially hook-like shape. This portion is
exposed when the armrests are raised, and this may involve a risk for the user.
Also, there is the risk that clothes or body parts, e.g. the fingers of hand, may get
pinched between the locking members and the recesses formed on the underside
of the armrests.
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US-A-297801 discloses a solution similar to the preceding ones, wherein a ring is
fitted on the upper hook-like portion of each locking member, which ring extends
substantially transverse to the member. Here, the armrest is formed by a tubular
member having an elongate aperture formed on its underside, and the recesses
are formed on an elongate plate inserted in the tubular body itself. Upon assembly,
the ring is fitted on a locking member, whose upper portion is later inserted in the
corresponding tubular body at an end thereof. Hence, the upper hook-like portion
of the locking member may selectively engage in the recesses of the inner
elongated plate. Each armrest may be raised to change the recess in which the
corresponding locking member engages, but the vertical displacement is restricted
by the additional ring, which does not pass through the longitudinal aperture and
prevents the upper hook-like portion from coming off the tubular body.
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This arrangement reduces the risk for users to be injured or trapped in the device,
but has a considerably complex structure. Particularly, a relatively great number of
components is required and, accordingly, the assembly thereof is difficult and
time-consuming, whereby it has a poor cost effectiveness.
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US-A-20020121800 discloses yet another solution, similar to those described
above. Here, the locking member is formed by an elongate stem, with a T-shaped
upper portion, which is shaped in such a manner as to engage in a succession of
recesses on the underside of the armrest. The succession of recesses is covered
by a boxlike shield, which is screwed on the underside of the armrest and has an
elongate aperture which allows the passage of the stem of the locking member,
but not of its upper T-shaped portion. The latter prevents the locking member from
coming out of the boxlike shield when the armrests are raised to change the
backrest position, whereas the stem may slide freely along the aperture.
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Here again, a drawback consists in assembly complexity, particularly regarding the
upper T-shaped portion of the boxlike shield. Furthermore, the problem becomes
even more serious if the elongate aperture of the boxlike shield is relatively narrow
in the transverse direction. A narrow aperture of the boxlike shield is required by
certain safety standards and is anyway very useful to prevent fingers or other
objects from being dangerously introduced therethrough, but makes the assembly
difficult. One way to only partly facilitate the insertion of the upper T-shaped
portion in the boxlike shield consists in forming a thin connecting portion between
the upper T-shaped portion and the stem. This configuration simplifies the
assembly and the relative movements between the locking member and the
boxlike shield, but may cause a considerable loss in strength and reliability.
Disclosure of the invention
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A primary object of this invention is to obviate the above drawbacks, by providing a
cost-effective adjustment device for reclining chairs and the like.
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A particular object is to provide a device which is so designed as to prevent the
occurrence of potentially dangerous conditions for users, and to comply with the
current safety standards.
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A further object of the invention is to provide a device which has a small number of
components and allows a relatively easy assembly.
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Yet another particular object is to provide a sturdy and reliable device, whose
features remain unchanged with time.
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Another particular object is to provide a simple and easily implementable method
for fabricating the device.
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These objects, as well as others that will be more apparent hereinafter, are
achieved, according to claim 1, by an adjustment device for the armrests of a
reclining or the like chair, comprising at least one locking member, which is
engageable in a plurality of adjacent retaining seats, that may be associated to an
armrest of a chair to selectively lock said armrest in predetermined positions. The
retaining seats are at least partly covered by a boxlike shield, having an elongate
aperture for the passage of the locking member, to protect the hands of a user.
The locking member has a platelike shape, its maximum thickness being smaller
than the minimum width of said elongate aperture, and has an expanded head
which defines a longitudinal axis. Such head is designed for selective engagement
in each retaining seat and is joined to a main body which is connected to the frame
of the chair by a twisted portion, adapted to allow the insertion of the head in the
elongate aperture from below, by relative rotation about the longitudinal axis.
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Thanks to this particular configuration, an adjustment device may be obtained that
is relatively easy to fabricate and fit on the armrests of a chair, while being sturdy
and reliable, also by appropriately sizing all of its components.
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Preferably, the elongate aperture extends substantially parallel to the armrest and
has such a maximum width as to prevent any accidental introduction of users'
fingers and, particularly, equal to or less than 7 mm.
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This particular arrangement allows to prevent any potentially dangerous situation
for users and to comply with the safety standards in force.
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Appropriately, the plurality of retaining seats is monolithic for the boxlike shield.
This particular characteristic will help to reduce the overall number of components
and to simplify fabrication and assembly steps.
Brief Description of the Drawings
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Further features and advantages of the invention will be more clearly understood
from the detailed description of several preferred, but not exclusive embodiments
of an adjustment device according to the invention, illustrated by way of a nonlimiting
example with reference to the attached drawings, in which:
- FIG. 1 is a perspective view of a chair according to the invention;
- FIG. 2 is a perspective view of a device according to the invention;
- FIG. 3 is a top view of a detail of the device as shown in Fig. 2;
- FIG. 4 is a side view of the detail of FIG. 3;
- FIG. 5 is a side view of the detail of FIG. 3, in an intermediate processing
step;
- FIG. 6 is a sectional view of a further detail of the device as shown in Fig. 2;
- FIG. 7 is a second sectional view of the detail of FIG. 6;
- FIG. 8 is a front view of the detail of FIG. 6;
- FIGS. 9, 10, 11 are three sectional side views of the device of FIG. 2,
showing two successive steps of the fabrication and assembly method according
to the invention.
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Detailed description of a preferred embodiment
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Particularly referring to the above Figures, an adjustment device according to the
invention is described, which is generally designated with numeral 1, and may be
fitted on the armrests B of a chair C, armchair, lounge chair or the like, to change
the inclination of the backrest R.
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The device 1 comprises at least one locking member 2, which is engageable in a
plurality of adjacent retaining seats 3. The retaining seats 3 are designed to be
associated to a corresponding armrest B of a chair C, whereas the locking
member 2 is designed to be fitted on the frame S of the chair C. Also, the armrest
B is advantageously hinged at one end E with a side of the reclining backrest R.
Hence, any displacement of the armrest B relative to the frame S causes the
backrest R to rotate and accordingly, by changing the retaining seat 3 in which the
locking member 2 is engaged, the backrest R may be locked in a desired angular
position. The device 1 may be mounted in the same manner on both armrests B of
the chair C.
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The retaining seats 3 are at least partly covered by a boxlike shield 4, to protect
the hands of a user. The locking member 2 may engage in the retaining seats 3 by
being at least partly inserted in the boxlike shield 4. Therefore, in order to allow the
passage of the locking member 2, the boxlike shield 4 has an elongate aperture 5.
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The locking member 2 has a platelike shape, its maximum thickness M being
smaller than the minimum width H of the elongate aperture 5, and a head 6 which
defines a longitudinal axis L and is designed to be selectively engaged in each of
the retaining seats 3. The head 6 is expanded and has a pair of projecting
appendices 7, which extend in the same direction transverse to the longitudinal
axis L. These transverse appendices 7 have such an extension, transverse to the
longitudinal axis L, as to prevent the head 6 from coming out of the boxlike shield
4, once the latter has been properly inserted in the shield.
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The locking member 2 comprises a main body 8, which is connected to the head 6
by a twisted portion 9. This main body 8 has the function of connecting the locking
member 2 to the frame S of the chair C, whereas the twisted portion 9 is shaped in
such a manner as to allow the insertion of the head 6 in the elongate aperture 5
from below, by relative rotation thereof about the longitudinal axis L. The head 6
has such a maximum thickness as to allow insertion thereof in the elongate
aperture 5, with the projecting appendices 7 being substantially parallel to the
aperture. The twisted portion 9 also allows the head 6 to rotate and engage in a
retaining seat 3, with the projecting appendices 7 disposed orthogonal or anyway
inclined relative to the elongate aperture 5, so as to prevent the head 6 from
coming out of the boxlike shield 4. Thanks to the twisted portion 9, the connection
between the head 6 and the main body 9 is strong and safe, as well as very easily
insertable in the elongate aperture 5, even in case the latter has a relatively small
minimum width H.
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The elongate aperture 5 extends substantially parallel to the armrest B and has
such a maximum width as to prevent any accidental introduction of users' fingers.
Advantageously, the maximum width H' of the elongate aperture 5 is equal to or
less than 7 mm.
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Suitably, the twisting angle of the twisted portion 9 may be of about 90°, so that
the head 6 and the main body 8 are substantially orthogonal to each other.
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The plurality of retaining seats 3 may be made of one piece with the boxlike shield
1. In one particular embodiment, as shown in the annexed drawings, each
retaining seat 3 comprises two substantially parallel and adjacent saw teeth 10,
which are designed to interact with the head 6 to prevent any relative
displacement between the armrest B and the frame S of the chair C.
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Advantageously, each saw tooth 10 has a first edge 11, which is adapted to
engage an end of the head 6 and a second edge 12, adjacent to the first edge, but
having a different inclination. Particularly, the inclination of the second edge 12 is
gentler than that that of the first edge 11, to assist the user in the change of the
retaining seat 3 in which the head 6 is engaged and accordingly in the adjustment
of the inclination of the backrest R.
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The above device 1 is fabricated and mounted in a plurality of successive steps.
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In a first step a), a reclining chair C is provided, comprising a frame S for a seating
surface and a movable backrest R, hinged to the frame.
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A second step b) includes the preparation of at least one monolithic assembly 13,
comprising a plurality of adjacent retaining seats 3 and a boxlike covering shield 4
which has an elongated aperture 5 of a predetermined maximum width H'.
Particularly, a first plate of a rigid material is blanked, thereby obtaining a flat blank
(not shown) of the monolithic assembly 13. Blanking also includes drilling of holes
14 for through screws. Later, the flat blank is folded according to a predetermined
geometry to bring a plurality of saw teeth 10 to their operating position and to form
the boxlike shield 4.
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A third step c) includes the provision of a pair of armrests B, and a fourth step d)
includes the preparation of a monolithic assembly 13 on each of the armrests B.
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In a fifth step e), a locking member 2 is formed for each monolithic assembly 13.
Each locking member 2 comprises an expanded head 6 which defines a
longitudinal axis L and at least one twisted portion 9 whereby it is joined to a main
body 8 for connection to the frame S. Particularly, a second plate made of a rigid
material is blanked, to obtain the flat blank 15 of the locking member 2, comprising
the head 6 and the main body 8, joined together by a flat joining portion 16.
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Then, the head 6 is rotated about the longitudinal axis L relative to the main body
8 to cause the plastic deformation of the flat joining portion 16 and to form the
twisted portion 9. Particularly, the angular extension of such rotation may be
substantially equal to a right angle. By this arrangement, the width N of the flat
joining portion 16 may be so sized as to provide the desired strength and reliability
and such width N may be even larger than the minimum width H of the elongate
width H of the elongate aperture 5. In fact, the twisted portion 9 can pass through
the elongate aperture 5 and allows proper positioning of the head 6 in a retaining
seat 3 due to its own shape, although the flat joining portion 16 has a larger width
N than that the elongate aperture 5.
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Appropriately, the main body 8 of the locking member 2 may be drawn.
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In a sixth step f), the locking member 2 is mounted onto on the frame S.
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A seventh step g), as may be shown in FIGS. 9 and 10, includes the insertion of
the head 6 in the boxlike shield 4, through the elongate aperture 5. In a
subsequent step h), the boxlike shield 4 associated to each armrest B is rotated
relative to the catch member 2 about the longitudinal axis L of the head 6, as
shown in FIGS. 10 and 11.
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Finally, in a further step i), each armrest B is connected to the backrest R.
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The above description clearly shows that the device according to the invention
fulfils the predetermined objects and particularly the possibility to select the proper
width of the flat joining portion even though the widened aperture is relatively
narrow, provides the catch member with the desired strength and reliability with
time, without affecting other advantages, such as functionality and easy assembly.
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The device of this invention is susceptible of numerous modifications and
changes, all falling within the scope of the appended claims. All the details thereof
may be replaced by other technically equivalent parts, and the materials may vary
depending on different needs, without departure from the scope of the invention.
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While the device has been described with particular reference to the
accompanying figures, the numerals referred to in the disclosure and claims are
only used for the sake of a better intelligibility of the invention and shall not be
intended to limit the claimed scope in any manner.
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The instant application is based upon and claims priority of patent application no.
VI2002A000221, filed on 18.10.2002 in Italy, the disclosure of which is hereby
expressly incorporated in reference thereto.
