U.S. patent application number 09/967679 was filed with the patent office on 2003-04-03 for wheeled chair with a seat locking unit.
Invention is credited to Chao, Ya-Chen.
Application Number | 20030062753 09/967679 |
Document ID | / |
Family ID | 25513153 |
Filed Date | 2003-04-03 |
United States Patent
Application |
20030062753 |
Kind Code |
A1 |
Chao, Ya-Chen |
April 3, 2003 |
Wheeled chair with a seat locking unit
Abstract
A wheeled chair includes a wheeled frame having an upright post
that defines a vertical axis, a seat mounted rotatably on the
upright post so as to be turnable relative to the wheeled frame
about the vertical axis, and a seat locking unit including a
retaining member secured to the upright post and formed with a
plurality of retaining grooves, a mounting seat secured to the
seat, and a spring-biased tongue member disposed above the
retaining grooves, mounted movably on the mounting seat, and
operable so as to be moved between a locking position, in which,
the tongue member is moved downwardly to selectively engage one of
the retaining grooves so as to prevent turning of the seat relative
to the wheeled frame, and an unlocking position, in which, the
tongue member is moved upwardly to disengage from the selected one
of the retaining grooves so as to permit turning of the seat
relative to the wheeled frame.
Inventors: |
Chao, Ya-Chen; (Ta-Li City,
TW) |
Correspondence
Address: |
Ronald R. Santucci
711 Third Avenue, 20th Floor
New York
NY
10017-4014
US
|
Family ID: |
25513153 |
Appl. No.: |
09/967679 |
Filed: |
September 28, 2001 |
Current U.S.
Class: |
297/344.22 |
Current CPC
Class: |
A61G 5/10 20130101; A61G
5/1072 20130101; A61G 5/1067 20130101; A61G 5/043 20130101; A61G
5/1089 20161101 |
Class at
Publication: |
297/344.22 |
International
Class: |
A47C 003/18 |
Claims
I claim:
1. A wheeled chair comprising: a wheeled frame having an upright
post that has a top end and that defines a vertical axis; a seat
disposed over said upright post and having a bottom side, and an
inserting protrusion that projects downwardly from said bottom side
and that is mounted rotatably on said top end of said upright post
so as to permit turning of said seat relative to said wheeled frame
about said vertical axis; and a seat locking unit including a
retaining member secured to said top end of said upright post and
formed with a plurality of retaining grooves which are angularly
spaced apart from each other, a mounting seat secured to said
bottom side, and a spring-biased tongue member disposed above said
retaining grooves, mounted movably on said mounting seat, and
operable so as to be moved between a locking position, in which,
said tongue member is moved downwardly by an urging force to
selectively engage one of said retaining grooves so as to prevent
turning of said seat relative to said wheeled frame about said
vertical axis, and an unlocking position, in which, said tongue
member is moved upwardly to disengage from the selected one of said
retaining grooves so as to permit turning of said seat relative to
said wheeled frame about said vertical axis.
2. The wheeled chair of claim 1, wherein said upright post is
cylindrical in shape and is formed with a cylindrical top recess,
said inserting protrusion being cylindrical in shape and having a
frusto conical bottom end received in said top recess.
3. The wheeled chair of claim 1, further comprising an operating
member that includes a lever which is mounted turnably on said
mounting seat, which extends in a transverse direction relative to
said vertical axis to define a horizontal axis, and which has one
end projecting laterally from said bottom side of said seat, and
the other end disposed adjacent to said tongue member, said
operating member further including a pushing arm that is transverse
to and that extends from the other end of said lever to engage said
tongue member so as to lift said tongue member to move upwardly to
disengage from the selected one of said retaining grooves when said
lever is turned in a direction about said horizontal axis.
4. The wheeled chair of claim 3, wherein said mounting seat is
formed with a tongue receiving space for receiving said tongue
member, a lever receiving space for receiving fittingly the other
end of said lever, and an arm receiving space which is transverse
to and which is in spatial communication with said lever receiving
space and said tongue receiving space and which receives said
pushing arm, said tongue receiving space having cylindrical upper
and lower sections, said upper section having a diameter greater
than that of said lower section, said tongue member having upper
and lower portions which are respectively received in said upper
and lower sections and which cooperately define a neck
therebetween, said lower portion of said tongue member extending
through said lower section of said tongue receiving space and into
the selected one of said retaining grooves when said tongue member
is at said locking position, said upper portion of said tongue
member being formed with a top groove, said seat locking unit
further including a coil spring that has one end received in said
top groove, and the other end abutting against said bottom side of
said seat So as to urge said tongue member to move downwardly, said
pushing arm having a free end that is disposed underneath and that
is in contact with said neck so as to lift said tongue member
against the urging force of said coil spring when said lever is
turned in said direction about said horizontal axis.
5. The wheeled chair of claim 4, wherein said retaining member is
includes a circular plate that has an upper face and an arcuate
stopper projecting upwardly from said upper face and engageable
with said mounting seat so as to limit the extent of turning of
said mounting seat relative to said upright post.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the invention
[0002] This invention relates to a wheeled chair, more particularly
to a wheeled chair with a seat locking unit.
[0003] 2. Description of the related art
[0004] FIGS. 1 to 3 illustrate a conventional wheeled chair which
includes a wheeled frame 10 with a cylindrical upright post 11, a
seat 22 with an inserting protrusion 221 projecting downwardly into
a top recess of the upright post 11 and being turnable relative to
the upright post 11, and a seat locking unit 30 mounted on a bottom
side 222 of the seat 22. The seat locking unit 30 includes a
retaining plate 31 secured to the upright post 11 and formed with a
plurality of retaining grooves 311, a lever 34 having one end 341
pivoted to the bottom side 222 of the seat 22 and the other end 342
projecting laterally and outwardly from the bottom side 222 of the
seat 22, a tongue 343 projecting from the lever 34 toward the
retaining plate 31, and a coil spring 35 having one end secured to
the bottom side 222 of the seat 22 and the other end secured to the
lever 34 so as to urge the lever 34 to move toward the retaining
plate 31. The lever 34 is turnable toward and away from the
retaining plate 31 about a vertical axis, which is parallel to the
upright post 11, between a locking position (see FIG. 2), in which,
the tongue 343 is urged by the coil spring 35 to move toward the
retaining plate 31 so as to engage a selected one of the retaining
grooves 311, and an unlocking position (see FIG. 3), in which, the
tongue 343 moves away from the retaining plate 31 against an urging
force of the coil spring 35 so as to disengage from the selected
one of the retaining grooves 311 and so as to permit rotation of
the seat 22 relative the upright post 11. Two diametrically
disposed stoppers 32, 33 project downwardly from the bottom side
222 of the seat 22, and are disposed adjacent to the retaining
plate 31. The retaining plate 31 further has a protrusion 312
projecting laterally and outwardly from a peripheral edge thereof
so as to selectively engage one of the stoppers 32, 33 (see FIG. 3)
when the seat 22 turns relative to the upright post 11.
[0005] The conventional wheeled chair is disadvantageous in that
operation of the lever 34 as such is not ergonomical and that a
relatively strong coil spring 35 is needed to enhance engagement
between the tongue 343 and the selected retaining groove 311. As a
consequence, the operation of the lever 34 is relatively laborious.
Moreover, disengagement of the tongue 343 from the selected
retaining groove 311 is required when the seat 22 is to be
separated from the wheeled frame 10, which results in inconvenience
during the disassembly operation.
SUMMARY OF THE INVENTION
[0006] Therefore, it is an object of the present invention is to
provide a wheeled chair with a seat locking unit that is capable of
overcoming the aforementioned drawbacks.
[0007] According to the present invention, a wheeled chair
comprises: a wheeled frame having an upright post that has a top
end and that defines a vertical axis; a seat disposed over the
upright post and having a bottom side, and an inserting protrusion
that projects downwardly from the bottom side and that is mounted
rotatably on the top end of the upright post so as to permit
turning of the seat relative to the wheeled frame about the
vertical axis; and a seat locking unit including a retaining member
secured to the top end of the upright post and formed with a
plurality of retaining grooves which are angularly spaced apart
from each other, a mounting seat secured to the bottom side, and a
spring-biased tongue member disposed above the retaining grooves,
mounted movably on the mounting seat, and operable so as to be
moved between a locking position, in which, the tongue member is
moved downwardly by an urging force to selectively engage one of
the retaining grooves so as to prevent turning of the seat relative
to the wheeled frame about the vertical axis, and an unlocking
position, in which, the tongue member is moved upwardly to
disengage from the selected one of the retaining grooves so as to
permit turning of the seat relative to the wheeled frame about the
vertical axis.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] In drawings which illustrate an embodiment of the
invention,
[0009] FIG. 1 is a perspective view of a conventional wheeled chair
with a seat locking unit;
[0010] FIG. 2 is a fragmentary bottom view of the wheeled chair
with the seat locking unit of FIG. 1 at an locking position;
[0011] FIG. 3 is a fragmentary bottom view of the wheeled chair
with the seat locking unit of FIG. 1 at a unlocking position;
[0012] FIG. 4 is a perspective view of a wheeled chair with a seat
locking unit embodying this invention;
[0013] FIG. 5 is a fragmentary exploded view of the wheeled chair
with the seat locking unit of FIG. 4;
[0014] FIG. 6 is an exploded perspective view of the seat locking
unit of FIG. 4;
[0015] FIG. 7 is a partly sectional view of the seat locking unit
of FIG. 4 at a locking position;
[0016] FIG. 8 is a fragmentary bottom view of the wheeled chair of
FIG. 4; and
[0017] FIG. 9 is a partly sectional view of the seat locking unit
of FIG. 4 at an unlocking position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0018] FIGS. 4 to 9 illustrate a wheeled chair embodying this
invention. The wheeled chair includes: a wheeled frame 40 having an
upright post 41 that has a top end 413 and that defines a vertical
axis (X); a seat 52 disposed over the upright post 41 and having a
bottom side 523, and an inserting protrusion 522 that projects
downwardly from the bottom side 523 and that is mounted rotatably
on the top end 413 of the upright post 41 so as to permit turning
of the seat 52 relative to the wheeled frame 40 about the vertical
axis (X); and a seat locking unit including a retaining member 61
secured to the top end 413 of the upright post 41 and formed with a
plurality of retaining grooves 611 which are angularly spaced apart
from each other, a mounting seat 62 secured to the bottom side 523,
and a spring-biased tongue member 63 disposed above the retaining
grooves 611, mounted movably on the mounting seat 62, and operable
so as to be moved between a locking position (see FIG. 7), in
which, the tongue member 63 is moved downwardly by an urging force
to selectively engage one of the retaining grooves 611 so as to
prevent turning of the seat 52 relative to the wheeled frame 40
about the vertical axis (X), and an unlocking position (see FIG.
9), in which, the tongue member 63 is moved upwardly to disengage
from the selected one of the retaining grooves 611 so as to permit
turning of the seat 52 relative to the wheeled frame 40 about the
vertical axis (X).
[0019] The upright post 41 is cylindrical in shape and is formed
with a cylindrical top recess 412. The inserting protrusion 522 is
cylindrical in shape and has a frusto conical bottom end 5221
received in the top recess 412 so as to permit turning of the seat
52 relative to the upright post 41.
[0020] The wheeled chair further includes an operating member that
includes a lever 64 which is mounted turnably on the mounting seat
62, which extends in a transverse direction relative to the
vertical axis (X) to define a horizontal axis (Y), and which has
one end 642 projecting laterally and outwardly from the bottom side
523 of the seat 52, and the other end 641 disposed adjacent to the
tongue member 63. The operating member further includes a pushing
arm 643 that is transverse to and that extends from the other end
641 of the lever 64 to engage the tongue member 63 so as to lift
the tongue member 63 to move upwardly to disengage from the
selected one of the retaining grooves 611 when the lever 64 is
turned in a direction about the horizontal axis (Y).
[0021] The mounting seat 62 is formed with a tongue receiving space
621 for receiving the tongue member 63, a lever receiving space 622
for receiving fittingly the other end 641 of the lever 64, and an
arm receiving space 623 which is transverse to and which is in
spatial communication with the lever receiving space 622 and the
tongue receiving space 621 and which receives the pushing arm 643.
The tongue receiving space 621 has cylindrical upper and lower
sections 6211, 6212. The upper section 6211 has a diameter greater
than that of the lower section 6212. The tongue member 63 has
cylindrical upper and lower portions 632, 633 which are
respectively received in the upper and lower sections 6211, 6212
and which cooperately define a neck 634 therebetween. The lower
portion 633 of the tongue member 63 extends through the lower
section 6212 of the tongue receiving space 621 and into the
selected one of the retaining grooves 611 when the tongue member 63
is at the locking position. The upper portion 632 of the tongue
member 63 is formed with a top groove 631. The seat locking unit
further includes a coil spring 635 that has one end received in the
top groove 631, and the other end abutting against the bottom side
523 of the seat 52 so as to urge the tongue member 63 to move
downwardly. The pushing arm 643 has a free end that is disposed
underneath and that is in contact with the neck 634 so as to lift
the tongue member 63 against an urging force of the coil spring 635
when the lever 64 is turned about the horizontal axis (Y).
[0022] The retaining member 61 includes a circular plate that has
an upper face 614 and an arcuate stopper 613 projecting upwardly
from the upper face 614 and engageable with the mounting seat 62 so
as to limit the extent of turning of the mounting seat 62 relative
to the upright post 41.
[0023] With the seat locking unit of this invention, the
aforementioned drawbacks associated with the prior art can be
eliminated.
[0024] With the invention thus explained, it is apparent that
various modifications and variations can be made without departing
from the spirit of the present invention. It is therefore intended
that the invention be limited only as recited in the appended
claims.
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