Information
-
Patent Grant
-
6761274
-
Patent Number
6,761,274
-
Date Filed
Thursday, February 6, 200321 years ago
-
Date Issued
Tuesday, July 13, 200419 years ago
-
Inventors
-
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 211 207
- 211 175
- 211 204
- 211 1051
- 403 1091
- 403 1092
- 403 1095
- 280 793
- 248 132
- 248 149
- 248 161
- 248 410
- 248 411
- 248 412
- 248 157
-
International Classifications
-
Abstract
A rack includes a horizontal framework for holding or displaying various things. The horizontal framework can be adjusted in height by a plurality of expandable units by which the horizontal framework is mounted on a base. The expandable units are formed of an outer tube, and an inner tube slidably fitted into the outer tube in conjunction with a locating structure having a cylindrical seat, a sleeve, and an elastic lock ring. The lock ring is retained in one end of the sleeve which is rotatably fastened to the cylindrical seat. The bottom end of the inner tube is slidably fitted into the top end of the outer tube and is embraced by the lock ring which is made compact to embrace tightly the bottom end of the inner tube when the sleeve is turned clockwise. The lock ring is relieved of the pressure when the sleeve is turned counterclockwise.
Description
RELATED U.S. APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
REFERENCE TO MICROFICHE APPENDIX
Not applicable.
FIELD OF THE INVENTION
The present invention relates generally to a rack, and more particularly to a structure by which each of the expandable units of the rack is located securely.
BACKGROUND OF THE INVENTION
The adjustable racks of the prior art comprise a plurality of expandable units, each being formed of an outer tube and an inner tube slidably fitted into the outer tube. The racks can be thus adjusted in height by locating the inner tube inside the outer tube. The locating of the inner tube is done by a locating knob, which is turned to press against the outer wall of the inner tube. Such a locating means as described above is rather primitive and ineffective at best. The locating knob is apt to become loosened upon being impacted. In addition, the locating knob undermines the aesthetic effect of the racks. Moreover, the outer wall of the inner tube is susceptible to damage that is resulted from the mechanical friction between the locating knob and the inner tube.
BRIEF SUMMARY OF THE INVENTION
The primary objective of the present invention is to provide the expandable units of a rack with a locating structure which is free of the drawbacks of the locating means of the prior art racks described above.
In keeping with the principle of the present invention, the foregoing objective of the present invention is attained by a locating structure comprising a cylindrical seat, a sleeve, and a lock ring. The cylindrical seat is fitted over the top end of an outer tube of an expandable unit and is provided in the top end thereof with a tapered receptacle. The sleeve is rotatably fastened with the seat for retaining the lock ring which has a tightening portion of a tapered construction. The bottom end of an inner tube of the expandable unit is fitted into the top end of the outer tube via the lock ring and the sleeve. As the sleeve is turned clockwise in relation to the seat, the lock ring is carried along to move downward such that the tightening portion of the lock ring is forcibly contained in the receptacle of the top end of the seat. As a result, the bottom end of the inner tube is securely embraced by the tightening portion of the lock ring. When the sleeve is turned counterclockwise, the lock ring is carried along to move upward such that the tightening portion of the lock ring is no longer forcibly contained in the receptacle of the seat. As a result, the bottom end of the inner tube is no longer intimately embraced by the tightening portion of the lock ring and can be therefore moved up and down inside the outer tube.
The features and the advantages of the present invention will be more readily understood upon a thoughtful deliberation of the following detailed description of a preferred embodiment of the present invention with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1
shows a perspective view of the preferred embodiment of the present invention.
FIG. 2
shows an exploded perspective view of the expandable unit of the preferred embodiment of the present invention.
FIG. 3
shows an exploded sectional view of the expandable unit of the preferred embodiment of the present invention.
FIG. 4
shows a longitudinal sectional view of the expandable unit of the preferred embodiment of the present invention in the movable state.
FIG. 5
shows a longitudinal sectional view of the expandable unit of the preferred embodiment of the present invention in the fixed state.
DETAILED DESCRIPTION OF THE INVENTION
As shown in
FIGS. 1-3
, a coat rack
05
embodied in the present invention comprises a base
07
, two horizontal bars
06
, and four expandable units
10
which are uprightly mounted on the base
07
for supporting adjustably the two horizontal bars
06
. The two horizontal bars
06
are used to hold a plurality of coat hangers. The two horizontal bars
06
can be adjusted in height, thanks to the expandable units
10
.
The four expandable units
10
are formed of an outer tube
11
, an inner tube
12
, and a locating structure comprising a cylindrical seat
20
, a sleeve
30
, and a lock ring
40
. The outer tube
11
is uprightly fastened at the bottom end with the base
07
and is fitted at the top end into the bottom end of the cylindrical seat
20
. The inner tube
12
is fastened at the top end with one end of the horizontal bar
06
and is slidably fitted at the bottom end into the top end of the outer tube
11
through the cylindrical seat
20
in conjunction with the sleeve
30
and the lock ring
40
by which the bottom end of the inner tube
12
is securely located inside the top end of the outer tube
11
.
As shown in
FIGS. 2 and 3
, the cylindrical seat
20
is provided in the interior with a longitudinal slot
21
dimensioned to accommodate the top end of the outer tube
11
. The cylindrical seat
20
is further provided at the top end with a tapered receptacle
22
in communication with and in alignment with the longitudinal slot
21
. The cylindrical seat
20
is further provided with an outer threaded portion
23
.
The sleeve
30
is provided with an inner threaded portion
31
engageable with the outer threaded portion
23
of the cylindrical seat
20
. The sleeve
30
is further provided in the inner wall of the top end thereof with an annular retaining projection
32
. The sleeve
30
is rotatably fastened with the cylindrical seat
20
such that the inner threaded portion
31
of the sleeve
30
is engaged with the outer threaded portion
23
of the cylindrical seat
20
.
The lock ring
40
is made of an elastic material, such as rubber, and is provided with a flange
44
, and a tightening portion
43
of a tapered construction and extending from the flange
44
. The lock ring
40
is further provided in the outer wall with an annular retaining groove
42
which is located between the flange
44
and the tightening portion
43
. The lock ring
40
is retained in the top end of the sleeve
30
such that the retaining projection
32
of the sleeve
30
is retained in the retaining groove
42
of the lock ring
40
, and that the tightening portion
43
of the lock ring
40
is fitted into the receptacle
22
of the cylindrical seat
20
, as shown in
FIGS. 4 and 5
. It must be noted here that the lock ring
40
is provided with a center through hole
41
, which extends through the tightening portion
43
.
The expandable unit
10
is assembled in such a way that the bottom end of the inner tube
12
is slidably fitted into the top end of the outer tube
11
through the lock ring
40
, the sleeve
30
and the cylindrical seat
20
, and that the bottom end of the inner tube
12
is embraced by the tightening portion
43
of the lock ring
40
, as shown in FIG.
4
. The bottom end of the inner tube
12
can be moved up and down inside the top end of the outer tube
11
, so as to adjust the height of the horizontal bar
06
. The bottom end of the inner tube
12
is located by turning the sleeve
30
in the clockwise direction, as illustrated in FIG.
5
. As a result, the lock ring
40
is carried along with the sleeve
30
to move toward the cylindrical seat
20
so as to force the tightening portion
43
of the lock ring
40
to move further into the receptacle
22
of the cylindrical seat
20
. In light of the elasticity of the lock ring
40
, the tightening portion
43
of the lock ring
40
is pressed by pressure to embrace tightly the inner tube
12
, which is thus located securely. In another words, the bottom end of the inner tube
12
can not be moved up and down in the inside of the outer tube
11
. If a readjustment is called for, the sleeve
30
is turned in the counterclockwise direction, as shown in FIG.
4
. As a result, the lock ring
40
is carried along with the sleeve
30
to move in the direction away from the cylindrical seat
20
, so as to cause the tightening portion
43
of the lock ring
40
to separated from the receptacle
22
of the cylindrical seat
20
. The tightening portion
43
of the lock ring
40
is thus relieved of the pressure to become less compact. In another words, the inner tube
12
is no longer embraced tightly by the tightening portion
43
of the lock ring
40
and can be therefore moved up and down in the inside of the outer tube
11
.
The embodiment of the present invention described above is to be regarded in all respects as being illustrative and nonrestrictive. Accordingly, the present invention may be embodied in other forms without deviating from the spirit thereof. The present invention is therefore to be only by the scope of the following claims.
Claims
- 1. A rack comprising:a base; a plurality of expandable units, each unit being fastened uprightly on said base and comprised of an outer tube, an inner tube, and a locating structure, said outer tube being fastened at a bottom end to said base, said inner tube being slidably fitted at a bottom end into a top end of said outer tube in conjunction with said locating structure; and one or more horizontal bars, each bar being adjustably supported by a top end of said inner tube of said expandable units; wherein said locating structure comprises: a cylindrical seat provided in an interior with a longitudinal slot, in a top end with a tapered receptacle in communication with and in alignment with said longitudinal slot, and in an outer wall with an outer threaded portion whereby said longitudinal slot is dimensioned to receive the top end of said outer tube, a sleeve comprised of an inner threaded portion, and in an inner wall of a top end, an annular retaining projection whereby said sleeve is rotatably fastened to said cylindrical seat such that said inner threaded portion of said sleeve is engaged with said outer threaded portion of said cylindrical seat; and a lock ring comprised of an elastic material and comprised of a flange, a tightening portion of a tapered construction and extending from said flange, an annular retaining groove located between said flange and said tightening portion, and a center through hole extending from said flange through said tightening portion, said lock ring being retained in the top end of said sleeve such that said retaining projection of said sleeve is retained in said retaining groove of said lock ring, and such that said tightening portion of said lock ring is extended into said receptacle of the top end of said cylindrical seat, and such that said tightening portion of said lock ring embraces the bottom end of said inner tube whereby said tightening portion is pressed thereagainst by said receptacle to become compact so as to embrace the bottom end of said inner tube when said sleeve is turned clockwise in relation to said cylindrical seat, said tightening portion of said lock ring being capable of relaxing when said sleeve is turned counterclockwise in relation to said cylindrical seat, thereby enabling the bottom end of said inner tube to be moved up and down inside the top end of said outer tube.
- 2. The rack as defined in claim 1, wherein said lock ring is comprised of rubber.
US Referenced Citations (8)
Foreign Referenced Citations (1)
Number |
Date |
Country |
004020434 |
Jan 1991 |
DE |