Note: Descriptions are shown in the official language in which they were submitted.
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LOCKING SYSTEM FOR ROCKING CHAIR
FIELD OF THE INVENTION
The invention relates to rocking chairs, more specifically to an automatic
locking
system for a rocking chair where the chair is fixed in a locked position when
no
person is seated in the chair so as to prevent free unwanted movement of the
chair.
DESCRIPTION OF THE BACKGROUND ART
Various locking mechanisms for rocking chairs are currently known and used to
lock
a rocking chair from rocking when immobility of the chair is desired. Other
locking
mechanisms have been developed for a more precautionary purpose as they are
used to automatically prevent the rocking chair from moving once the user has
left
the seating portion of the chair. Such locking systems were needed to address
stability problems involving rocking chairs and users with reduced mobility.
Typical self-locking mechanisms for rocking chairs often involve the
interaction
between two component members located on the base of the chair causing the
chair
to be in a locked position when a person leaves the seating portion of the
chair.
A similar locking mechanism is disclosed in US patent 6,120,094 (Parent) where
a
rocking chair comprises a two part locking device having a downward oriented
toothed bar and a locking rod carried by the base and the seat respectively
which
are mutually engageable when the seat is unoccupied and where the chair is
automatically locked against rocking when a person leaves the seat.
US patent 6,997,510 (Guillot et al.) discloses another locking mechanism
mounted
on both the base and the seat assembly which includes a downfacing toothed
rack
and an arm lever that operatively cooperate.
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Another locking device is disclosed in US patent 6,588,841 (Hoffman), where a
first
toothed engagement member is oriented towards the bottom and is fixed to and
below a seat and a second engagement member is pivotally interconnected with
the
base and configured to engage the first engagement member in one of a
plurality of
engagement locations. In the locked position, the second engagement member
raises to engage with the first engagement member, and in the unlocked
position,
the second engagement member is lowered and disengages from the first
engagement member.
US patent 6,244,658 (Parent et al.) discloses a rocking chair with an
automatic
locking device comprising a two part ratchet locking device where a link rod
pivotally
links the rear of the seat to a pawl, with the pawl engaging the ratchet wheel
when
the seat is in an unoccupied position and clearing the ratchet wheel when the
seat is
occupied by a user.
The known prior art disclose locking mechanisms that are vertically mounted to
the
base of a chair and which are mutually engageable when a user has left the
seating
area.
However, these prior art systems utilize locking mechanisms that are very
often
bulky or difficult to dissimulate to their external configuration.
Consequently, there is
presently a need for a new locking mechanism that is more compact in size and
therefore easier to integrate to the overall structure of a chair. Also, there
is presently
a need for a locking mechanism made up of fewer parts and therefore that is
more
effective based on respective individual component tolerances.
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SUMMARY OF THE INVENTION
An object of the present invention is to provide a rocking chair with a
locking
mechanism that addresses at least one of the above-mentioned needs.
According to the present invention, there is provided a rocking chair
comprising:
- a base structure comprising:
- an upper part;
- a lower part;
- an exterior face;
- and an interior face;
- a seating structure, comprising opposing front and back ends as well as
opposing side ends, wherein the seating structure is mounted to the upper part
of
the base structure;
- a seat cushion support frame rockably mounted on the seating structure, the
seat cushion support frame having a front and rear portion;
- a seat cushion movably mounted on the seat cushion support frame having
limited up and down movement between a high limit position and a low limit
position;
- a stop carried by the seat cushion support frame and engaging the seat
cushion in the low limit position;
- a biasing mechanism biasing the seat cushion to the high position, wherein a
weight of a person seated on the seat cushion lowering the seat cushion to the
low
limit position against a bias of the biasing mechanism;
- a two part locking device, having a top part mounted to the seat cushion
support frame of the seating structure and a bottom part mounted to the base
structure, mutually engageable when the seat cushion is in the low position
and
clearing each other when the seat is in the high limit position;
whereby the rocking chair is automatically locked against rocking when a
person
leaves the seat cushion.
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A non-restrictive description of a preferred embodiment of the invention will
now be
given with reference to the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a front perspective view of a rocking chair according to a
preferred
embodiment of the present invention;
Figure 1 A is a magnified view of the locking device for the chair shown in
Figure 1;
Figure 2 is a rear perspective view of the chair shown in Figure 1 according
to a
preferred embodiment of the present invention;
Figure 2A is a magnified view of the biasing mechanism of the chair shown in
Figure
1;
Figure 3 is a side view of the base structure of the rocking chair shown in
Figure 1;
Figures 4 and 4A are perspective views of the locking device for the chair
shown in
Figure 1 and show the seat cushion is in the high position;
Figures 5 and 5A are perspective views of the locking device for the chair
shown in
Figure 1 and show the seat cushion in the low position;
Figures 6A to 6D are detailed views of the seat cushion support frame of the
chair
shown in Figure 1;
Figures 7A to 7E are different detailed rotational views of the stopper for
the locking
device of the chair shown in Figure 1.
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DETAILED DESCRIPTION OF THE INVENTION
As shown in figures 1 to 6, the present invention provides a self locking
rocking
chair. Figure 1 shows the rocking chair comprising a base structure 12
comprising
5 an upper part 40, a lower part 41, an exterior face 42 and an interior face
43. The
rocking chair further comprises a seating structure 10 having opposing front
45 and
back ends 44 as well as opposing side ends 46, wherein the seating structure
10 is
mounted to the upper part 40 of the base structure 12. Additionally, the
rocking chair
comprises a seat cushion support frame 16 rockably mounted on the seating
structure 10, where the seat cushion support frame 16 has a front 18 and rear
portion 20, as better shown in Figure 6.
As shown in Figure 1, the seat cushion 14 is movably mounted on the seat
cushion
support frame 16 having limited up and down movement between a high limit
position and a low limit position, represented in Figures 4 and 5
respectively.
As it can be seen in Figures 1, 2A, 5 and 6D, a stop 22 is carried by the seat
cushion
support frame 16 and engages the seat cushion 14 in the low limit position 90,
as
better detailed in Figure 5.
As it can better be seen in Figures 2 and 2A, the rocking chair further
comprises a
biasing mechanism 24 biasing the seat cushion 14 to the high position 70, the
high
position can better be seen in Figures 4 and 4A. The weight of a person seated
on
the seat cushion lowers the seat cushion 14 to the low limit position 90
against a
bias of the biasing mechanism 24, as it can be better seen in Figures 5 and
5A.
As seen in Figures 1, 1A, 4, 4A and 5, the rocking chair additionally
comprises a two
part locking device, having a top part 36 mounted to the seat cushion support
frame
16 of the seating structure 10 and a bottom part 30 mounted to the base
structure
12, as better shown in Figure 3.
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As better seen in Figures 5 and 5A, the two part locking device is mutually
engageable when the seat cushion is in the low position 90.
As it can better be seen in Figures 4 and 4A, the two parts of the locking
device clear
each other when the seat is in the high limit position 70, whereby the rocking
chair is
automatically locked against rocking when a person leaves the seat cushion.
Preferably, as seen in Figures 1 and 4, the front portion 18 of the before
mentioned
seat cushion support frame 16 is pivotably connected to the front end 45 of
the
seating structure, and wherein the biasing mechanism comprises a spring 71
attached to the rear end 20 of the seat cushion support frame and to the back
end
44 of said seating structure, as better shown in Figures 2 and 2A.
Preferably, as seen in Figures 1, 4, 4A, 5, 5A and 6, the stop 22 carried by
the seat
cushion support frame 16, engaging said seat cushion 14 in its low limit
position 90,
is an elongated tab protruding outwardly from the rear portion of the seat
cushion
support frame 20 and horizontally comes into contact with the back end of the
seating structure 44 when the cushion is in said low limit position 90.
In another preferred embodiment and as shown in Figure 1, the two part locking
device comprises a stopper actuator 36 carried by the seat cushion support
frame 16
as a first part and as better shown if Figure 3, a stopper 80 and comb
structure 81
carried by the base structure 12 as a second part 30 wherein the low limit
position of
the seat cushion mutually engages said stop actuator 36 against the stopper
and
comb structure, wherein the comb structure comprises a plurality of protruding
teeth
82 as it can better be seen in Figures 3 and 5A.
As better shown in Figures 3 and 4, the comb structure 81 is laterally mounted
to two
opposing exterior faces 42 of the upper part 40 of the base structure 12.
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Alternatively, in another preferred embodiment of the present invention, the
comb
structure is laterally mounted to two opposing interior faces of the upper
part of the
base structure.
Preferably, as better shown in Figures 3, 4A and 5A, the comb structure 81 is
a rack
gear and the stopper 80 comprises an arm 91 movably mounted on pivots to a
support on opposing outer faces of the base structure and has both a locked
and an
unlocked position. Alternatively, in another preferred embodiment of the
present
invention, stopper comprises an arm movably mounted on pivots to a support on
opposing inner faces of the base structure and has both a locked and an
unlocked
position.
As better shown in Figures 7A, 7D and 7E, a biasing means 92 biases the
stopper
80 in the locked position, and wherein contact between the stopper actuator 36
of
the seat cushion support frame 16 and the stopper engages the stopper in the
unlocked position, as shown in Figure 5A.
Preferably, as shown in Figures 7A, 7D and 7E, the arm 91 of the stopper 80 is
biased by a spring 92 to the locked positions. A stop 93 limits the arm while
in the
unlocked position. When the stopper 80 is in the locked position, as seen in
Figure
4A, it mutually engages with the protruding teeth 82 of the lateral comb
structure 81.
Therefore locking of the rocking chair occurs laterally on two opposing
exterior faces
of the base structure between the stopper and the teeth of the comb structure.
Alternatively, where the comb structure and the stopper are laterally mounted
on two
opposing interior faces of the base structure, locking of the rocking chair
occurs
laterally on two opposing interior faces of the base structure between the
stopper
and the teeth of the comb structure.
Although preferred embodiments of the present invention have been described in
detail herein and illustrated in the accompanying drawings, it is to be
understood that
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the invention is not limited to these precise embodiments and that various
changes
and modifications may be effected therein without departing from the scope or
spirit
of the present invention.
