U.S. patent application number 11/390059 was filed with the patent office on 2007-10-04 for telescopic support for armrest.
Invention is credited to Ching-Chang Wang.
Application Number | 20070228797 11/390059 |
Document ID | / |
Family ID | 41445665 |
Filed Date | 2007-10-04 |
United States Patent
Application |
20070228797 |
Kind Code |
A1 |
Wang; Ching-Chang |
October 4, 2007 |
Telescopic support for armrest
Abstract
A telescopic support is provided for an armrest of a chair. The
telescopic support includes a lower tube, an upper tube and a
helical spring. The lower tube is installed on the chair. The upper
tube telescopically receives the lower tube and supports the
armrest. The helical spring is axially positioned in the upper tube
and compressed between the upper tube and the lower tube for
automatically and smoothly lifting the upper tube from the lower
tube.
Inventors: |
Wang; Ching-Chang; (Wuchi
Town, TW) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
41445665 |
Appl. No.: |
11/390059 |
Filed: |
March 28, 2006 |
Current U.S.
Class: |
297/410 |
Current CPC
Class: |
A47C 1/03 20130101; A47C
1/0305 20180801 |
Class at
Publication: |
297/410 |
International
Class: |
A47C 7/36 20060101
A47C007/36 |
Claims
1. A telescopic support for an armrest of a chair, the telescopic
support comprising a lower tube (70; 60B), an upper tube (10; 10B)
for telescopically receiving the lower tube and supporting the
armrest and a helical spring (40) axially positioned in the upper
tube and compressed between the upper tube and the lower tube for
automatic and smooth lifting of the upper tube from the lower
tube.
2. The telescopic support according to claim 1 comprising a guide
(20) axially inserted in the upper tube for guiding the helical
spring.
3. The telescopic support according to claim 2 wherein the guide
comprises a rod inserted through the helical spring.
4. The telescopic support according to claim 3 wherein the rod
comprises a groove (23) and at least one aperture (25) in
communication with the groove, wherein the telescopic support
comprises: a retainer (60) fit in the lower tube, the retainer
comprising a channel (66) for receiving the rod and at least one
series of recesses (61) in communication with the channel; at least
one ball (50) positioned in the aperture of the rod for insertion
into selected one of the recesses of the retainer so as to retain
the guide and the upper tube in position relative to the retainer
and the lower tube; and a controller (30) movable in the groove of
the rod between a first position for pushing the ball into selected
one of the recesses of the retainer and a second position for
allowing the movement of the ball from the recesses.
5. The telescopic support according to claim 4 comprising a handle
(80) connected to the controller (30).
6. The telescopic support according to claim 5 wherein the upper
tube comprises an opening (13) through which the handle is exposed
from the upper tube.
7. The telescopic support according to claim 4 wherein the helical
spring is compressed between an end of the retainer and two
fasteners (22) secured to the rod.
8. The telescopic support according to claim 4 wherein the
controller comprises a wedge (35) for pushing the ball.
9. The telescopic support according to claim 4 comprising a spring
(37) for connecting the controller to the rod, thus tending to push
the controller to the first section from the second section.
10. The telescopic support according to claim 4 wherein the upper
tube comprises an enlarged upper portion (11), wherein the guide
comprises a platform (28) formed on the rod and positioned in the
enlarged upper portion of the upper tube.
11. The telescopic support according to claim 1 comprising a
platform (11B) installed on the upper tube and a cap (61B)
installed on the lower tube, wherein the helical spring is
compressed between the cap and the platform.
12. The telescopic support according to claim 11 wherein the
helical spring comprises a lower end fit on a portion of the cap so
that the helical spring is positioned.
13. The telescopic support according to claim 12 wherein the upper
tube comprises two lateral apertures (13B) defined therein, wherein
the lower tube comprises two opposite series of continuous
apertures (62) defined therein, wherein the telescopic support
comprises a controller (80B) with a latch (813B) movably inserted
in the lateral apertures of the upper tube and the two series of
continuous apertures of the lower tube, wherein the latch (813B)
comprises two reduced sections (814B) movable in the two series of
continuous apertures of the lower tube for allowing the movement of
the latch in and along the two series of continuous apertures of
the lower tube.
14. The telescopic support according to claim 13 wherein the
controller comprises a button (81B) connected to an end of the
latch, a washer (832B) and a fastener (831B) secured to an opposite
end of the latch through the washer so that the button and the
washer retain the latch in the upper tube.
15. The telescopic support according to claim 14 wherein the
controller comprises a spring (82B) compressed between the button
and the upper tube for moving the reduced sections of the latch
from the two series of continuous apertures of the lower tube.
16. The telescopic support according to claim 14 wherein the latch
comprises a ridge (815B) formed thereon, wherein the upper tube
comprises a cutout (15B) defined in the edge of each of the lateral
apertures for receiving the ridge of the latch so that the latch
cannot be rotated in the upper tube.
17. The telescopic support according to claim 14 wherein the upper
tube comprises a lip (14B) around one of the lateral apertures for
protecting the button.
18. The telescopic support according to claim 14 wherein the upper
tube comprises a lip (16B) around one of the lateral apertures for
protecting the washer and the fastener.
19. The telescopic support according to claim 18 wherein the
controller comprises a cover (84B) installed on the lip for
covering the washer and the fastener.
20. The telescopic support according to claim 19 wherein the cover
comprises a ridge (842B) formed thereon, wherein the lip defines,
on an internal side, a groove (161B) for receiving the ridge of the
cover.
Description
BACKGROUND OF INVENTION
[0001] 1. Field of Invention
[0002] The present invention relates to an armrest and, more
particularly, to a telescopic support for an armrest.
[0003] 2. Related Prior Art
[0004] Disclosed in Taiwanese Patent Publication no. 451658 is a
telescopic support for an armrest 4. The telescopic support
includes a first tube 1, a second tube 2 telescopically inserted in
the first tube 1 and a control device 3 provided between the first
tube 1 and the second tube 2. The first tube 1 includes two racks
111 and 121. The control device 3 includes two toothed wheels 32
and 33 attached to the second tube 2. The toothed wheels 32 and 33
can be engaged with two racks 111 and 121 of the first tube 1. A
detent 34 is pushed to the toothed wheels 32 and 33 by a spring 36.
The detent 34 includes two toothed portions 341 and 342 for
engagement with the toothed wheels 32 and 33 so that the toothed
wheels 32 and 33 can not rotate. Hence, the racks 111 and 121 can
neither be lifted nor lowered, i.e., the armrest 4 can neither be
lifted nor lowered. The detent 34 is connected to a switch 43 via a
cable 35 so that the detent 34 can be disengaged from the toothed
wheels 32 and 33 by operating the switch 43. The toothed wheels 32
and 33 can rotate. Hence, the racks 111 and 121 can be lifted or
lowered, i.e., the armrest 4 can be lifted or lowered. The lifting
of the armrest 4 is however not automatically conducted.
[0005] The present invention is therefore intended to obviate or at
least alleviate the problems encountered in prior art.
SUMMARY OF INVENTION
[0006] According to the present invention, telescopic support is
provided for an armrest of a chair. The telescopic support includes
a lower tube, an upper tube and a helical spring. The lower tube is
installed on the chair. The upper tube telescopically receives the
lower tube and supports the armrest. The helical spring is axially
positioned in the upper tube and compressed between the upper tube
and the lower tube for automatically and smoothly lifting the upper
tube from the lower tube.
[0007] The primary advantage of the telescopic support of the
present invention is the automatic and smooth lifting of the upper
tube from the lower tube for the use of the helical spring.
[0008] Other advantages and features of the present invention will
become apparent from the following description referring to the
drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0009] The present invention will be described through the
illustration of two embodiments referring to the drawings.
[0010] FIG. 1 is a perspective view of a telescopic support for an
armrest according to the first embodiment of the present
invention.
[0011] FIG. 2 is an exploded view of the telescopic support shown
in FIG. 1.
[0012] FIG. 3 is a cross-sectional view of the telescopic support
along a line 3-3 in FIG. 1.
[0013] FIG. 4 is a cross-sectional view of the telescopic support
in another position than shown in FIG. 3.
[0014] FIG. 5 is a cross-sectional view of the telescopic support
in another position than shown in FIG. 4.
[0015] FIG. 6 is a perspective view of a telescopic support for an
armrest according to the second embodiment of the present
invention.
[0016] FIG. 7 is an exploded view of the telescopic support shown
in FIG. 6.
[0017] FIG. 8 is a cross-sectional view of the telescopic support
along a line 8-8 in FIG. 6.
[0018] FIG. 9 is a cross-sectional view of the telescopic support
in another position than shown in FIG. 8.
[0019] FIG. 10 is a cross-sectional view of the telescopic support
in another position than shown in FIG. 9.
[0020] FIG. 11 is a cross-sectional view of the telescopic support
along a line 11-11 FIG. 6.
[0021] FIG. 12 is another cross-sectional view of the telescopic
support in another position than shown in FIG. 9.
DETAILED DESCRIPTION OF EMBODIMENTS
[0022] Referring to FIG. 1, there is shown a telescopic support for
an armrest according to a first embodiment of the present
invention. The telescopic support includes a lower tube 70 and an
upper tube 10.
[0023] Referring to FIG. 2, the upper tube 10 includes an enlarged
upper portion 11, an opening 13 near the enlarged upper portion 11
and two stems 12 on the enlarged upper portion 11.
[0024] A retainer 60 consists of two identical halves 64. The
retainer 60 includes an enlarged upper portion 62. The retainer 60
defines a channel 66 and two series of separate recesses 61 in
communication with the channel 66.
[0025] The retainer 60 is inserted in the lower tube 70 except the
enlarged upper portion 62 thereof positioned on an upper end of the
lower tube 70. The retainer 60 is secured to the lower tube 70 by a
screw 72 driven into a bore 63 defined in the retainer 60 through
an aperture 72 defined in the lower tube 70.
[0026] A guide 20 includes a rod 29 and a platform 28 formed on the
rod 23. The platform 28 defines two apertures 21 for receiving the
stems 12 of the upper tube 10 when the plat form 28 is installed on
the enlarged upper portion 11 of the upper tube 10 as the guide 20
is inserted in the upper tube 10. The platform 28 is secured to the
enlarged upper portion 11 of the upper tube 10 by two threaded
bolts 14.
[0027] The rod 29 defines a longitudinal groove 23 and two lateral
apertures 25 in communication with the groove 23. A stem 24 is
formed on the floor of the groove 23. A hook 27 is formed on the
floor of the groove 23 near a lower end of the rod 29. A restraint
26 is formed on each of two walls of the groove 23. Two screws 22
are driven into the rod 29.
[0028] Positioned in the apertures 25 are two balls 50 for
insertion into selected ones of the recesses 61 of the retainers
60.
[0029] A controller 30 includes a bent upper section 31, a bent
lower section 32 and a wedge 35 formed between the bent upper
section 31 and the bent lower section 32. The wedge 35 includes two
inclined facets 36 for pushing the balls 50. The controller 30
defines a slot 33 between the bent upper section 31 and the wedge
35.
[0030] The controller 30 is movable in the groove 23 while the slot
33 receives the stem 24. A tension spring 37 includes an upper end
hooked by the hook 32 and a lower end hooked by the hook 27 so as
to bias the wedge 35 against the balls 50.
[0031] The bent upper section 31 of the controller 30 is exposed
from the upper tube 10 through the opening 13. A handle 80 is
connected to the bent upper section 31 of the controller 30.
[0032] The rod 29 is inserted through a helical compression spring
40 that is provided between the enlarged upper portion 62 of the
retainer 60 and the screws 22 secured to the rod 29. Hence, the
helical compressing spring 40 tends to lift the guide 20 and the
upper tube 10 from the retainer 60 and the lower tube 70. An upper
end of the helical compression 40 contacts the platform 28 at two
symmetrical points centered at the rod 29. Therefore, the helical
compression spring 40 can lift the upper tube 10 from the lower
tube 70 very smoothly.
[0033] Referring to FIG. 3, the spring 37 pulls the controller 30
to a lower position. The wedge 35 comes between and pushes the
balls 50 into selected ones of the recesses 61 of the retainer 60.
Hence, the upper tube 10 cannot be moved towards and from the lower
tube 70.
[0034] Referring to FIGS. 4 and 5, a user can lift the handle 80 so
as to lift the controller 30. The wedge 35 is moved to an upper
position so that it is not between the balls 50. The balls 50 can
be moved from the recesses 61 of the retainer 60. The balls 50 will
not fall from the apertures 25 because of the restraints 26 and the
wedge 35. The upper tube 10 can be lowered and lifted relative to
the lower tube 70. Now, the helical compression spring 40 can lift
the upper tube 10 from the lower tube 70.
[0035] Referring to FIGS. 6 through 12, there is shown a telescopic
support according to a second embodiment of the present invention.
The telescopic support includes a lower tube 60B and an upper tube
10B.
[0036] The lower tube 60B defines two opposite series of apertures
62B in communication with one another. A cap 61B is installed on an
upper end of the lower tube 60B.
[0037] The upper tube 10B includes two opposite apertures 13B
defined therein, a cutout 15B defined in the edge of one of the
apertures 13B and two lips 14B and 16B each formed around related
one of the apertures 13B. The lip 16B includes a groove 161B on an
internal side.
[0038] A controller 80B includes a latch 813B, a spring 82B, a
threaded bolt 831B, a washer 832B and a cover 84B.
[0039] The latch 813B includes a button 81B formed at an end, a
ridge 815B longitudinally formed thereon and two reduced sections
814B.
[0040] The cover 84B includes a plurality of slits 841B defined in
the edge and a ridge 842B formed along the edge.
[0041] In assembly, the spring 40 is positioned in the upper tube
10B before the lower tube 60B is inserted in the upper tube 10B.
The spring 40 is compressed between the platform 11B and the cap
61B. The spring 40 tends to lift the upper tube 10B from the lower
tube 60B. A lower end of the spring 40 is fit on a portion of the
cover 61B so that the position of the spring 40 is retained and
that the upper end of the spring 40 is always located against the
center of the platform 11B. Hence, the spring 40 can lift the upper
tube 10B from the lower tube 60B smoothly.
[0042] The spring 82B is installed on the latch 813B that is
inserted in the apertures 13B and the series of apertures 62B. The
ridge 815B is positioned in the cutout 15B so that the latch 813B
cannot be rotated. The button 81B is biased by the spring 82B. The
threaded bolt 831B is driven in an opposite end of the latch 813B
through the washer 832B. The cover 84B is positioned in the lip
16B. The slits 841 facilitate the insertion of the cover 84B. The
ridge 842B is fit in the groove 161B so as to retain the cover 84B
in the lip 16B.
[0043] The upper tube 10B can be moved between lower and upper
positions on the lower tube 60B referring to FIGS. 8 and 10,
respectively.
[0044] Referring to FIG. 11, the reduced sections 814B of the latch
813B are not located in the two series of apertures 62B so that the
latch 813B cannot be moved in the two series of apertures 62B.
Hence, the position of the upper tube 10B on the lower tube 60B is
retained.
[0045] Referring to FIGS. 9 and 12, the button 81B is pressed so
that the reduced sections 814B of the latch 813B are located in the
two series of apertures 62B so that the latch 813B can be moved in
the two series of apertures 62B. Therefore, the position of the
upper tube 10B on the lower tube 60B can be changed.
[0046] The present invention has been described through the
illustration of the embodiments. Those skilled in the art can
derive variations from the embodiments without departing from the
scope of the present invention. Therefore, the embodiments shall
not limit the scope of the present invention defined in the
claims.
* * * * *