[0001] The present invention relates to rocker chairs and in particular to rocker chairs
for infants which are formed around a collapsible frame.
[0002] Infant rocker seats are well known in the art which are collapsible for compact storage.
Strict safety legislation exists relating to the design of such collapsible rocker
seats, in particular relating to the locking system utilised to prevent accidental
collapse of the frame when an infant is seated therein. In order to meet these requirements,
one existing design of collapsible rocker seat utilises two separate locking systems
which are remotely located from each other, a user being required simultaneously to
release a first lock with one hand and a second lock with the other hand. This system
has the drawback, however, that it is very cumbersome to operate since both hands
of the user are required to release the locks making it difficult then to press the
frame towards its closed position.
[0003] According to the present invention there is provided a collapsible chair frame comprising
a base having a pair of longitudinally extending side bars, a first pair of brackets
attached proximate to a first end of each side bar so as to be freely rotatable about
a first axis substantially perpendicular to said side bars, an actuation member extending
between and rotatably connected to each bracket of said first pair so as to be rotatable
relative to said first pair of brackets about a second axis parallel to but offset
from said first axis, a second pair of brackets secured proximate to a second end
of each side bar, a first pair of support bars each having a first end secured to
a respective one of opposing ends of said actuation member and a second end having
engagement means provided thereon, each of said first pair of support bars extending
from said actuation member at an inclined angle substantially towards said second
end of its respective side bar, and a second pair of support bars which extend at
an inclined angle substantially towards said first end of its respective side bar,
each second support bar having a first end rotatably connected to a respective one
of said second pair of brackets and a second end having engagement means provided
thereon, said engagement means of the second end of each of said second pair of support
bars engaging with the engagement means of the second end of an associated one of
the first pair of support bars, such that each of said second pair of support bars
and its associated one of the first pair of support bars are constrained to rotate
together, wherein said actuation member further includes locking means engageable
with said first pair of brackets to secure said actuation member against rotation
relative to said brackets, release means operable to move said locking means from
a locked position to an unlock position in order to release said actuation member
for rotation relative to said first pair of brackets, and safety catch means which,
in a first position interacts with the release means to prevent operation thereof
and in a second position is released from said release means so as to enable operation
thereof to unlock said actuation member from said brackets.
[0004] A collapsible chair frame in accordance with the invention has the advantage that
the provision of the release means and the safety catch means necessitates operation
of the two separate catches in sequence in order to enable collapse of the frame,
thereby reducing the possibility of accidental collapse, whilst the two catches can
be configured to enable operation with a single hand of a user, thereby simplifying
the collapse operation.
[0005] Preferably, a housing is provided on each side of the frame in which are received
the second end of a respective one of each of the first pair of support bars and the
second pair of support bars so as to maintain the engagement means provided thereon
in engagement. More particularly, the second end of each of the first and second pairs
of support bars are pivotally mounted in their respective housing, for example by
means of through pins, which maintain said ends in positions in which their engagement
means are engaged. The engagement means may particularly advantageously take the form
of gear teeth which may be formed directly on the second end of the each of the first
and second support bars, or may alternatively be formed on end plates which are separately
attached to said second ends.
[0006] The base of the frame preferably includes a pair of end bars which extend from proximate
ends of the side bars transversely of said side bars towards each other, each of said
first pair of brackets being rotatably mounted on the end of a respective one of the
end bars and the actuation member, which preferably takes the form of a handle, then
extends between said brackets substantially parallel to said end bars.
[0007] Preferably, tubing defining the plane of the seat and the back of the chair extend
between said side housings, in particular each of the back tubing and the seat tube
being substantially U-shaped with one end engaged in each of the side housings. The
back tubing may advantageously be pivotally connected to said side housings and include
locking means operable to lock the back tube in a number of different pivotal positions
relative to the side housing, thereby enabling adjustment of the angle of the back
of the seat.
[0008] The locking means preferably takes the form of a pair of pins which extend from opposing
ends of the actuation means and engage in complementary shaped recesses formed in
said first brackets, when the actuation means is properly aligned therewith, in order
to lock said actuation means against relative rotation, said release means operating
to retract said pins from said recesses in order to enable relative rotation to take
place. The pins are then attached either to common sides of separate pivot levers
or opposing sides of a common pivot lever, operation of the release means causing
rotation of the or each pivot lever in order to retract said pins.
[0009] In a particularly preferred embodiment, the release means is a button which projects
from the side of the actuation member and is depressible thereinto in order to operate
said locking means. More particularly, said button includes a pin which engages into
cam openings formed in opposing pivot levers to which said locking pins are connected,
movement of the button relative to said pivot levers causing rotation of said levers
in opposing directions, which, in turn, pulls said locking pins in opposite directs
into the actuation member. In this configuration, the safety catch takes the form
of a button which is slidably mounted in the actuation member and has at least one
projection which, in a first slide position of the safety catch, extends into the
path of movement of the button so as to prevent operation movement thereof, and in
a second position, is retracted from said path of movement so as to permit release
of said locking pins. In a further development, the safety catch is slidably mounted
for movement away from its first position in opposite directions such that in said
first position the button is locked against movement, and upon movement away from
the fist position in either direction, the button is free to be operated to release
the locking pins. In this way, operation by both left and right-handed users is possible.
Alternatively, however, the release means may take the form of a rotatable lever with
the safety catch having a projection which engages into an opening in the lever so
as to prevent rotation thereof. Preferably, biasing means such as a spring is associated
with the safety catch which biases it into a position in which operational movement
of the release means is prevent, the safety catch being manually retractable against
the loading of the biasing means.
[0010] Other developments and improvements will follow from the embodiment examples described
below.
[0011] In order that the invention may be well understood, there will now be described some
embodiments thereof, given by way of example, reference being made to the accompanying
drawings, in which:
Figure 1 is a perspective view of a rocker seat frame according to the invention in
an erect position;
Figures 2a to 2c are perspective views of the seat frame of Figure 1 at various stages
of collapse;
Figure 3 is a perspective view of the seat frame of Figure 1 in a collapsed position;
Figures 4a to 6b are enlarged views, at various stages of collapsed, of a gearing
mechanism coupling the movement of front and rear legs of the seat frame of Figure
1;
Figure 7a and 7b are an enlarged view of a locking mechanism of the seat frame according
to a first embodiment of the invention;
Figure 8 is a side view of the rocker seat of the invention;
Figure 9 is a rear perspective view of the seat frame of Figure 1 illustrating operation
of a seat back adjustment mechanism; and
Figure 10 is an enlarged view of a locking mechanism of the seat frame according to
a second embodiment of the invention.
[0012] Referring first to figures 1 to 3, there is shown a collapsible frame structure 1
of an infant's rocker chair as an embodiment example of the present invention. The
frame 1 comprises a base tube 10 having a first pair of longitudinally extending side
bars 10a, 10b, a rear cross bar 10c extending transversely between said side bars
10a, 10b at the rear of the frame 1, and a pair of front cross bars 10d, 10e which
extend transversely from the front end of each side 10a, 10b co-axially towards each
other partially across the front of the frame. As can be clearly seen in Figure 4a,
the side bars 10a, 10b are curved such that the sides, front and rear bars together
define a curved lower surface on which the base tube 10 can rock back and forth.
[0013] A mounting bracket 11a, 11b is rotatably mounted on the end of each of the front
cross bars 10d, 10e of the base tube 10, each bracket having an arm 12a, 12b extending
radially from the respective front cross bar 10d, 10e upon which it is mounted, and
a release bar 13 extends between the mounting brackets and is pivotally attached to
each of the arms 12a, 12b of the brackets 11a, 11b at a point offset from the front
cross bars 10d, 10e such that the release bar 13 is rotatable relative to said brackets
11a, 11b about an axis which is parallel to but radially offset from the axis longitudinal
axis of the front cross bars 10d, 10e.
[0014] The release bar 13 further includes a pair of locking pins 14 which extend along
an axis which is parallel to but offset from the axis of rotation of the release bar
13 relative to the brackets 11 a, 11b, which project from opposing ends of the release
bar 13 and which are engageable in complementary shaped recesses formed in the brackets
when the pins are substantially aligned with the front cross bars 10d, 10e so as to
lock the release bar 13 against rotation relative to the brackets.
[0015] An aperture 15 which extends radially of the longitudinal axis of the release bar
13 is formed in each end of the release bar 13 and are oriented such that they point
upwards towards the rear of the frame at an inclined angle when the locking pins 14
are engaged in the recesses of the brackets 11a, 11b so as to lock the release bar
to the brackets as shown in Figure 1. A pair of front support bars 16, 17 each have
a first end 16a, 17a which engages in one of the apertures 15 in the release bar 13
and is secured therein by means of a cross bolt, and a second end 16b, 17b on which
is fastened a geared plate 18 and which is pivotally housed within a respective side
housing 2a, 2b. A pair of rear support brackets 20a, 20b are also fixed to the base
tube 10, one being connected to each side bar 10a, 10b in longitudinal alignment proximate
to the rear cross bar 10c, each support bracket 20a, 20b having an associated rear
support bar 21, 22 pivotally attached thereto at one end 21 a, 22a, the associated
rear support bar extending forwardly from the support bracket 20a, 20b, being pivotally
connected to a respective one of the side housings 2a, 2b at a point which is offset
from the point of pivotal attachment of the corresponding front support bar 16, 17,
and having a geared plate 24 fastened to its upper end 21b, 22b, the teeth of which
mesh with the teeth of the geared plate 18 of the correspond front support bar 16,
17. In this way, the front and rear support bars 16, 17, 21, 22 on each side of the
frame are constrained to pivot within the side housings 2a, 2b together.
[0016] A substantially U-shaped seating tube 3 also has one end 3a, 3b securely fixed to
each of the side housings 2a, 2b such that the orientation of the seating tube 3 is
substantially fixed relative to the side housings 2a, 2b, and the seating tube 3 loops
forward between the side housings 3 so as to form a front support for the chair. As
shown in more detail in Figure 4b, each side housing 2a, 2b has a cylindrical recess
4a, 4b formed therein into which the corresponding end 3a, 3b of the seating tube
3 is close tolerance fit so that the seating tube is prevented from pivotal movement
relative to the side housings 2a, 2b, the ends 3a, 3b being secured in the respective
recesses 4a, 4b by means of a bolt 5 as shown in Figures 4a to 6b. It can also be
seen that each end 3a, 3b has more than one through opening into which the bolts 5
are engageable, such that distance by which the seating tube 3 extends forward from
the side housings 3 a, 3b can be adjusted.
[0017] Similarly, a substantially U-shaped rear tube 6 also has one end 6a, 6b pivotally
attached to each side housing 2a, 2b with the sides of the rear tube 6 extend substantially
rearwardly from the side housings 2a, 2b as shown in Figure 2c. Locking means 7 is
associate with the rear tube 6, in the form of a U shaped locking lever which engages
with opposing ends 7a, 7b with locking recesses 8 formed in the side housings 2a,
2b to lock the rear tube in one of a plurality of different pivotal positions in a
manner which is well known in the art and which will not therefore be described further.
[0018] Referring now to Figure 7a and 7b, there is shown a detailed view of a release mechanism
housed within the release bar 13 for disengaging the pins 14 from the brackets 11a,
11b so as to enable the frame to be collapsed as described hereinafter. Each pin 14
is attached to a respective pull cable 30, which, in turn, are attached to a lever
arm 31 c, 31 d of one of a pair of actuation plates 31 a, 31 b, each of which is pivotally
mounted on one of a pair of spaced apart, parallel extending pivot posts 32a, 32b
such that each plate 31a, 31b can be pivoted about the longitudinal axis of its associated
post 32a, 32b in order to rotate its lever arm away from the end of the release bar
13 with which its locking pin 14 is associated and to retract the locking pin 14 into
the release bar. The plates 31 a, 31b furthermore overlap each other and each plate
31 a, 31b has, formed in its overlapping section, a slot 33a, 33b, the sides of which
form camming surfaces. A press button 34 is mounted in the release bar behind the
plates 31a, 31b so as to be slidably movable relative thereto in a plane perpendicular
to the axes of rotation of the plates 31a, 31b. The button 34 furthermore has an actuation
pin 35 which engages in both slots 33a, 33b of the two plates 31a, 31b, such that
upon sliding movement of the button 34 relative to the plates 31a, 31b in a first
direction, a camming action is developed between the actuation pin 35 and the slots
33a, 33b which causes the lever arms 31c, 31d to rotate away from each other, thereby
pulling the cables 30 away from the associated ends of the release bar 13 and hence
retracting the pins thereinto, and upon sliding movement of the button 34 relative
to the plates 31a, 31b in a second direction opposite said first direction, a camming
action is developed between the actuation pin 35 and the slots 33a, 33b which causes
the lever arms 31c, 31d to rotate towards each other, thereby relieving the tension
in the cables 30. Springs 37 which are associated with each pin 14 and bias each said
pin into an extending position then operate to return the pins 14 to their locking
positions.
[0019] In order to prevent accidental operation of the press button 34, a slide button 36
is provided in the release bar 13 opposite the press button 34 which has projections
37 formed thereon which extend towards the press button 34. The slide button is slidably
moveable laterally in a direction perpendicular to the direction of sliding movement
of the press button 34 from a central position in which the projections 37 thereon
engage with the press button 34 so as to prevent movement of the press button towards
the slide button 36 and hence prevent release of the locking pins 14, in either a
left or right direction to a side position in which the projections 37 are disengaged
from the press button so that the press button is free to move towards the slide button
in order to retract the pins 14 into the release bar as described above and hence
unlock the release bar from the brackets. Springs 38 cooperate with the slide button
36 so as to bias it into its central position, and the projections 37 have inclined
surfaces which engage with the press button 34 as the slide moves back towards its
first position, developing a camming action therewith which urged the press button
away from the slide button 36 and back into its locked position.
The fame operates as follows:
[0020] With the release bar 14 in its locked position shown in Figure 1, the front support
bars 16, 17 are locked in position due to their inability to pivot relative to the
release bar 14, which, in turn, locks the rear support bars 18, 19 again movement
due to the meshing engagement of the gear teeth carried on the ends 16b, 17b, 18b,
19b thereof which are housed within the side housings. The seat and rear tubes 6,
7 are therefore securely supported in elevated positions above the base tube 10 by
the support bars 16, 17, 18, 19.
[0021] In order to collapse the frame, the user moves the slide button 36 towards its second
position using the thumb and then presses the projection portion of the press button
34 using the fingers of the same hand, which causes the locking pins to be retracted
into the release bar 13, thereby unlocking for rotation relative to the brackets 11a,
11b. The release bar can then be rotated about the brackets 11a, 11b, whilst, at the
same time, the brackets 11a, 11b are pivoted about the front cross bars 10e, 10f.
This double pivot allows the release bar to be translated forwards relative to the
frame, moving the front ends 16a, 17a of the front support bars 16, 17 with it. This,
is turn causes the front support bars 16, 17 to rotate anticlockwise relative to the
side housings 2a, 2b, the meshing engagement of the teeth on the rear support bars
18, 19 causing those rear support bars to pivot clockwise relative to the side housings
2a, 2b, and the frame thereby collapses onto the base tube 10 under its own weight
as shown in Figures 2a to 3.
[0022] In order to re-erect the frame, the side housings 2a, 2b are simply lifted away from
the base tube 10, which causes the release bar and brackets to move back into engagement
and lock together.
[0023] It will, of course, be understood that the press button mechanism of Figure 7 may
be substituted with mechanism without departing from the invention. For example, a
rotating lever may be utilised, a suite slide or press button being provided which
releases and/or engages a pin into the lever plate so as to prevent its rotational
movement and hence provide the necessary double lock.
[0024] Alternatively, each locking pin 14 may be connected to a linkage 102 which, in turn,
connects to a rotating rod 103, rotation of the rod 103 causing a pin 103a, 103b carried
eccentrically on the end thereof to move away from or towards the locking pin 14 so
as, respectively, to pull or push an actuation lever 104a, 104b in order to retract
or extend the pin. A press button 105 is then provided having an opening 106 formed
therein in which engages an arm 107 which extends radially from the centre of the
rod 103. The button is mounted in the release bar 13 for sliding movement both parallel
and perpendicular to the longitudinal axis of the rod 103, and the opening 106 is
L-shaped such that, in a first longitudinal position of the press button 105 relative
to the release bar 13, movement of the press button perpendicular to the rod by pressing
it into the release bar 13 causes the opening 106 to movement relative to the arm
107 in the manner of a lost motion coupling without the sides thereof engaging the
arm 107 and hence without effecting any rotation of the rod 107. Upon sliding the
press button 105 longitudinally relative to the release bar 13 towards a second longitudinal
position, the arm 107 is moved towards the closed end of the base of the L-shaped
opening 106, whereupon movement of the press button towards the rod causes the arm
107 to be engaged by the side of the opening 106, moving it transversely relative
to the rod 103 and thereby rotating the rod 103, which in turn, retracts the pins.
Springs 109, 110 are provided within the release bar 13 which bias the press button
both away from the rod 103 and longitudinally into its first longitudinal position
as shown in Figure 10.
[0025] In an variation of Figure 10 which is not illustrated, instead having an L-shaped
opening in the press button, locking ribs may be provided on the casing of the release
rod 13, which, when the button is in its first longitudinal position, engage with
the press button to prevent its movement towards the rod but which, upon movement
of the press button into its second longitudinal position, are aligned with slots
formed in the press button so as to enable the button to be depressed and the pins
thereby to be unlocked. In all embodiments, it will be seen that the double operation
of the lock required to collapse the frame ensures that accidental release cannot
occur.
1. A collapsible chair frame (1) comprising a base (10) having a pair of longitudinally
extending side bars (10a, 10b), a first pair of brackets (11a, 11b) attached proximate
to a first end of each side bar (10a, 10b) so as to be freely rotatable about a first
axis substantially perpendicular to said side bars (10a, 10b), an actuation member
(13) extending between and rotatably connected to each bracket (11a, 11b) of said
first pair so as to be rotatable relative to said first pair of brackets (11a, 11b)
about a second axis parallel to but offset from said first axis, a second pair of
brackets (20a, 20b) secured proximate to a second end of each side bar (10a, 10b),
a first pair of support bars (16, 17) each having a first end (16a, 17a) secured to
a respective one of opposing ends of said actuation member (13) and a second end (16b,
17b) having engagement means (18) provided thereon, each of said first pair of support
bars (16, 17) extending from said actuation member (13) at an inclined angle substantially
towards said second end of its respective side bar 10a, 10b), and a second pair of
support bars (21, 22) which extend at an inclined angle substantially towards said
first end of its respective side bar (10a, 10b), each second support bar (21, 22)
having a first end (21a, 22a) rotatably connected to a respective one of said second
pair of brackets (20a, 20b) and a second end (21b, 22b) having engagement means (24)
provided thereon, said engagement means (24) of the second end (21b, 22b) of each
of said second pair of support bars (21, 22) engaging with the engagement means (18)
of the second end (16b, 17b) of an associated one of the first pair of support bars
(16, 17), such that each of said second pair of support bars (21, 22) and its associated
one of the first pair of support bars (16, 17) are constrained to rotate together,
wherein said actuation member (13) further includes locking means (14) engageable
with said first pair of brackets (11 a, 11b) to secure said actuation member (13)
against rotation relative to said brackets (11a, 11b), release means (34) operable
to move said locking means (14) from a locked position to an unlock position in order
to release said actuation member (13) for rotation relative to said first pair of
brackets (11a, 11b) , and safety catch means (36) which, in a first position interacts
with the release means (34) to prevent operation thereof and in a second position
is released from said release means (34) so as to enable operation thereof to unlock
said actuation member (13) from said brackets (11a, 11b).
2. A collapsible chair frame according to claim 1, wherein a housing (2a, 2b) is provided
on each side of the frame (1) in which are received the second end (16b, 21b; 17b,
22b) of a respective one of each of the first pair of support bars (16, 17) and the
second pair of support bars (21, 22) so as to maintain the engagement means (18, 24)
provided thereon in engagement.
3. A collapsible chair frame according to claim 2, wherein the second ends (16b, 21b;
17b, 22b) of each of the first and second pairs of support bars (16, 21; 17, 22) are
pivotally mounted in their respective housing (2a; 2b), preferably said second ends
(16b, 21b, 17b, 22b) being retaining in said housings (2a, 2b) by means of pins.
4. A collapsible chair frame according to claim 2 or claim 3, wherein tubing defining
the plane of a seat portion (3) and a back portion (6) of the chair extends between
said side housings (2a, 2b).
5. A collapsible chair frame according to any of the preceding claims, wherein the engagement
means take the form of geared plates (18, 24), which preferably are formed separately
from said first pair of support bars (16, 17).
6. A collapsible chair frame according to any of the preceding claims, wherein the base
of the frame includes a pair of end bars (10d, 10e) which extend from proximate first
ends of the side bars (10a, 10b) transversely of said side bars (10a, 10b) towards
each other, each of said first pair of brackets (11a, 11b) being rotatably mounted
on the end of a respective one of the end bars (10d, 10e) , and the actuation member
(13) extending between said brackets (11 a, 11b) substantially parallel to said end
bars (10d, 10e).
7. A collapsible chair frame according to claim 6, wherein said locking means comprises
a pair of pins (14) which extend from opposing ends of the actuation member (13) and
engage in complementary shaped recesses formed in said first brackets (11 a, 11b)
in order to lock said actuation member (13) against relative rotational movement,
said release means (34) operating to retract said pins (14) from said recesses.
8. A collapsible chair frame according to claim 7, wherein each pin (14) is attached
to an associated pivot lever (31a, 31b), operation of said release means (34) effecting
rotation of said pivot levers (31a, 31b) in order to retract said pins (14).
9. A collapsible chair frame according to claim 7, wherein said pins (14) are attached
to opposite sides of a common pivot lever, operation of said release means (34) effecting
rotation of said pivot lever in order to retract said pins.
10. A collapsible chair frame according to claim 8 or claim 9, wherein the release means
(34) is a button which projects from the side of the actuation member (13) and which
includes an actuation pin (35) that engages into a cam opening (33a, 33b) formed in
the or each pivot lever to which said pins (14) are attached, movement of the button
(34) relative to the or each pivot lever causing operative rotation thereof which
retracts said pins (14) into the actuation member (13).
11. A collapsible chair frame according to claim 10, wherein said safety catch (36) is
slidably mounted in the actuation member (13) and has at least one projection (37)
which, in a first slide position of the safety catch (36), extends into the path of
movement of the release means (34) so as to prevent operative movement thereof, and
in a second position, is retracted from said path of movement so as to permit release
of said locking pins (14).
12. A collapsible chair frame according to claim 8 or claim 9, wherein the release means
(34) is a rotatable lever, rotation of which effects rotation of the or each pivot
lever, the safety catch having a projection which engages with said release means
in order to prevent rotational movement thereof.