U.S. patent application number 10/413291 was filed with the patent office on 2004-10-21 for on a wheel of a rack.
Invention is credited to Liu, Wen-Che.
Application Number | 20040208693 10/413291 |
Document ID | / |
Family ID | 33158548 |
Filed Date | 2004-10-21 |
United States Patent
Application |
20040208693 |
Kind Code |
A1 |
Liu, Wen-Che |
October 21, 2004 |
ON A WHEEL OF A RACK
Abstract
A wheel of a rack consists of a wheel support, a sleeve inserted
into a tube of a rack, a supporting member joined to both the
sleeve and a top of the wheel support, and a screw projecting from
the supporting member and screwed into the sleeve; a step-shaped
portion being formed on top of the supporting member to fit with a
cavity on the sleeve bottom; a resilient C-shaped ring being fitted
around an annular groove of the sleeve to contact an inner side of
the tube; the groove being shaped so that a sideways facing portion
thereof tapers off towards a lower end; thus, the ring will move to
the bigger upper section of the sideways facing annular portion to
be pressed against the inner side of the tube with bigger pressure
when a downward force is applied on the sleeve.
Inventors: |
Liu, Wen-Che; (Taipei,
TW) |
Correspondence
Address: |
ROSENBERG, KLEIN & LEE
3458 ELLICOTT CENTER DRIVE-SUITE 101
ELLICOTT CITY
MD
21043
US
|
Family ID: |
33158548 |
Appl. No.: |
10/413291 |
Filed: |
April 15, 2003 |
Current U.S.
Class: |
403/345 |
Current CPC
Class: |
Y10T 16/204 20150115;
B60B 33/0068 20130101; Y10T 16/199 20150115; B60B 33/0049 20130101;
Y10T 16/21 20150115; B60B 33/0005 20130101; B60B 33/0007 20130101;
Y10T 16/201 20150115; B60B 33/0057 20130101; B60B 33/0073 20130101;
Y10T 403/70 20150115; B60B 33/0021 20130101; B60B 33/0039 20130101;
B60B 33/0002 20130101 |
Class at
Publication: |
403/345 |
International
Class: |
F16D 001/00 |
Claims
What is claimsed is:
1. An improvement on a wheel of a rack, comprising a wheel support
for holding a wheel part in position; a sleeve inserted into a
lower end of one of vertical support tubes of a rack and having a
central screw hole; a supporting member for supporting the sleeve;
the supporting member being turnably connected to a top of the
wheel support; the supporting member having a polygonal portion for
allowing a wrench to be used on; and a screw projecting upwards
from a middle of the polygonal portion and screwed into the screw
hole of the sleeve; and being characterized by: a round step-shaped
portion formed on a middle of the polygonal portion, and a round
cavity formed on a lower end of the sleeve for fitting with the
round step-shaped portion; a corrugated surface formed on an
annular portion of a lower end of the sleeve, and an elongated
extension portion at an upper end of the sleeve; and an annular
groove formed around an outer side of the elongated extension
portion of the sleeve, and a resilient and enlargeable C-shaped
ring fitted around the annular groove; the annular groove being
shaped so that a sideways facing annular portion thereof tapers off
towards a lower end; the C-shaped ring being in contact with an
inner side of the vertical support tube.
2. The wheel of a rack as claimed in claim 1, wherein the C-shaped
ring projects beyond the sleeve when it is located around the lower
end of the sideways facing annular portion of the annular
groove.
3. The wheel of a rack as claimed in claim 1, wherein the sleeve
has a plurality of trenches formed on an outer side thereof,
extending from a top and in communication with the annular groove.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a wheel, more particularly
one, which is used with a rack, and made in such manner as to be
securely and steadily joinable to a vertical tube of the rack, and
of which service life is relatively long.
[0003] 2. Brief Description of the Prior Art
[0004] Conventional wheels of racks can be general grouped into
ones usable with racks for supporting heavy objects, and ones
usable with racks for relatively light objects. Referring to FIGS.
5, and 6, a wheel 10 suitable for use with racks for heavy objects
includes a wheel part, a connecting sleeve 130, and a connecting
part consisting of a round platform 110 and a screw 120; the
connecting sleeve 130 has a screw hole, and is screwed to the screw
120, and closely inserted into a lower end of a vertical support
tube 140 of a rack for connecting the wheel 10 to the rack. Wheels
suitable for use with racks for light objects are usually formed
with, like wheels of office chairs, an up-projecting connecting
post for insertion into a lower end of a vertical tube of a
rack.
[0005] The first kind of wheels are found to have a disadvantage
that the connecting sleeve 130 is prone to separate from the tube
140 and the screw 120 when the rack is being moved around,
especially when the rack is loaded with heavy objects, because the
sleeve 130 is merely inserted into the tube 140 without any
securing means provided on the joint between both, and because the
sleeve 130 is merely connected to the screw 120 by means of screw
threads, and is merely supported on the round platform 110 without
any securing means provided on the joint between both. Furthermore,
the screw 120 can be bent and damaged due to the heavy load if the
sleeve 130 becomes loose on the screw 120.
SUMMARY OF THE INVENTION
[0006] It is a main object of the present invention to provide a
wheel, which can be securely and steadily joined to a vertical tube
of a rack; thus, the wheel can't become loose or separate from the
rack even if the rack is being moved around with heavy load.
[0007] The wheel of this invention consists of a wheel support for
holding a wheel part in position, a sleeve inserted into a lower
end of one vertical tube of a rack, a supporting member joined to
both the sleeve and a top of the wheel support, a screw projecting
upwards from the polygonal portion and screwed into a screw hole of
the sleeve, a round step-shaped portion formed on top of the
supporting member to fit with a cavity on a lower end of the
sleeve, a corrugated surface formed on an annular portion of the
sleeve for increasing friction, and a resilient C-shaped ring
fitted around an annular groove of the sleeve; the ring contacts an
inner side of the tube to prevent the sleeve from separating from
the tube; the annular groove is shaped so that a sideways facing
annular portion thereof tapers off towards a lower end, i.e.
similar to an middle section of an outer side of an inverted
cone.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The present invention will be better understood by referring
to the accompanying drawings, wherein:
[0009] FIG. 1 is an exploded perspective view of the wheel of a
rack according to the present invention,
[0010] FIG. 2 is a cross-sectional view of the wheel of a rack
according to the present invention,
[0011] FIG. 3 is a partial cross-sectional view of the wheel of the
invention, showing one of the functions of the C-shaped ring,
[0012] FIG. 4 is a partial cross-sectional view of the wheel of the
invention, showing the other function of the C-shaped ring,
[0013] FIG. 5 is an exploded perspective view of the conventional
wheel of a rack as described in the Background, and
[0014] FIG. 6 is a cross-sectional view of the conventional wheel
of a rack.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] Referring to FIG. 1, a preferred embodiment of a wheel 1 of
a rack in the present invention includes a support 11, a wheel part
12 connected to the support 11, a supporting platform 13 pivotally
connected to a top of the support 11, and a connecting sleeve
2.
[0016] The supporting platform 13 is formed with a polygonal
portion, a round step-shaped portion 14 on a middle portion of the
polygonal portion, and a screw 15 projecting upwards from a middle
portion of the step-shaped portion 14; the platform 13 is further
formed with an annular trench (not numbered) around a lower end of
the step-shaped portion 14, as shown in FIG. 2.
[0017] The connecting sleeve 2 is formed with a corrugated surface
21 on a lower portion of an outer side thereof, an elongated
extension portion 22, a central screw hole 23 extending up from a
bottom thereof, a round cavity 24 on a lower end for fitting with
the step-shaped portion 14 of the supporting platform 13, at least
one trench 25 formed on an outer side thereof and extending from a
top of the elongated extension portion 22, and an annular groove 26
formed on the outer side of the elongated extension portion 22 and
in communication with the trench 25; the trench 25 is provided for
allowing plating liquid to flow through when the sleeve 2 is being
plated; the edges of the trench 25 can form friction with an inner
side of a vertical tube 140 of a rack when the sleeve 2 is fitted
into the tube 140; the annular groove 26 is shaped such as to have
an annular sideways facing portion 261 similar to an middle section
of an outer side of an inverted cone, as shown in FIGS. 2 to 4,
i.e. a lower section of the annular sideways facing portion 261 is
smaller than an upper section in diameter; the sleeve 2 further has
an annular protrusion 28 at a lower end for fitting in the annular
trench of the platform 13.
[0018] A C-shaped ring 27 is provided for fitting around the
annular groove 26; the C-shaped ring 27 is relatively resilient,
and can be enlarged when force is exerted sideways on the inner
edges thereof. In addition, the C-shaped ring 27 is formed with
such a size as to project at least slightly beyond the annular side
of the sleeve 2 when it is located around the smaller lower section
of the annular sideways facing portion 261.
[0019] In combination, the sleeve 2 is joined to the support 11
with the screw hole 23 being screwed to the screw 15, and with the
round cavity 24, and the annular protrusion 28 being respectively
fitted with the step-shaped portion 14, and the annular trench (not
numbered) of the platform 13. A wrench can be fitted around to the
polygonal portion of the platform 13, and turned to help secure the
connection. The C-shaped ring 27 is positioned around the annular
groove 26. Then, the connecting sleeve 2 is tightly inserted into a
lower end of a vertical tube 140 of a rack with both the corrugated
surface 24 and the C-shaped ring 27 being in close contact with the
inner side of the tube 140, as shown in FIG. 2.
[0020] Referring to FIG. 3, because the C-shaped ring 27 projects
beyond the annular side of the sleeve 2, it can closely contact
with the inner side of the tube 140 to help prevent the sleeve 2
from falling out of the tube 140 even if it is located around the
smaller lower section of the annular sideways facing portion
261.
[0021] Referring to FIG. 4, the C-shaped ring 27 will be relocated
around the larger upper section of the annular sideways facing
portion 261, and enlarged to have a bigger diameter when the sleeve
2 is moved down relative to the tube 140 therefore the C-shaped
ring 27 can form still firmer connection with the tube 140 if an
external downward force is exerted on the sleeve 2. In other words,
the C-shaped ring 27 can effectively prevent the sleeve 2 from
falling off.
[0022] From the above description, it can be easily understood that
besides the C-shaped ring 27 preventing the wheel from separating
from the tube 140, the wheel of the present invention has
advantages as followings:
[0023] 1. The wheel can be steadily connected to the lower end of
the vertical tube 140 of the rack because of friction between the
corrugated surface 21 of the sleeve 2 and the tube 140.
[0024] 2. The sleeve 2 has the round cavity 24, and the annular
protrusion 28 respectively fitting with the step-shaped portion 14,
and the annular trench of the supporting platform 13 therefore it
is very steady on the platform 13, and in turns, service life of
the wheel will be longer.
[0025] 3. The elongated extension portion 22 makes the sleeve 2
still steadier.
[0026] 4. The wheel has a polygonal portion on the supporting
platform 13 therefore a wrench can be used to help increase the
firmness of the combination.
* * * * *