U.S. patent number 3,628,844 [Application Number 05/010,011] was granted by the patent office on 1971-12-21 for storage cabinet with revolving shelves.
Invention is credited to Bruce A. Preston.
United States Patent |
3,628,844 |
Preston |
December 21, 1971 |
STORAGE CABINET WITH REVOLVING SHELVES
Abstract
Mounted within a square storage cabinet is a tier of revolving
shelves each shaped generally as a three-quarters circle having a
diameter approximately equal to the square dimension of the cabinet
to avoid wasted space in the cabinet. Each shelf is formed with one
straight edge located to enable tiers of trays attached to two
swinging cabinet doors to be made of an optimum depth permitting
the trays to fill the space between the shelves and the doors when
the latter are closed. Detent mechanisms hold the shelves in
centered positions within the cabinet and resist any tendency of
the shelves to spin uncontrollably when turned out of the centered
positions. The door trays are hooked detachably onto standards
fastened to the inner sides of the doors and are constructed to
avoid leaving objectionable gaps between the doors and the
trays.
Inventors: |
Preston; Bruce A. (Rockford,
IL) |
Family
ID: |
21743301 |
Appl.
No.: |
05/010,011 |
Filed: |
February 9, 1970 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
713820 |
Mar 18, 1968 |
|
|
|
|
Current U.S.
Class: |
312/305;
108/139 |
Current CPC
Class: |
A47B
49/004 (20130101) |
Current International
Class: |
A47B
49/00 (20060101); A47b 088/00 (); A47b 095/00 ();
A47b 011/00 () |
Field of
Search: |
;312/305,324,202,326
;248/243,417 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Gilliam; Paul R.
Parent Case Text
CROSS-REFERENCE TO A RELATED APPLICATION
This application is a division of my copending application Ser. No.
713,820, filed Mar. 18, 1968 and now abandoned.
Claims
I claim as my invention:
1. In a revolving shelf assembly adapted for mounting within a
cabinet, the combination of, an upright post, a tier of vertically
spaced and horizontally disposed shelves each mounted for rotation
and for up and down sliding on said post, a supporting hub fastened
to the underside of each shelf and rotatably and slidably
telescoped over said post, a cam telescoped over and fastened
rigidly to said post beneath each of said supporting hubs with each
supporting hub resting on its underlying cam, coacting cam surfaces
formed on the lower side of each supporting hub and the upper side
of each cam and engageable with one another to retain said shelf
releasably in a predetermined angular position relative to said
post, said cam surfaces being shaped to cause said shelf to slide
upwardly on said post in response to the shelf being positively
rotated from said predetermined position and thereafter bearing
frictionally against one another, each of said coacting cam
surfaces including a lower dwell portion extending around an arc of
predetermined length, two rise portions inclined upwardly from the
ends of said lower dwell portion, and an upper dwell portion
extending between the upper ends of said rise portions and around
an arc of greater length than said first arc, the respective cam
portions mating with one another when said shelf is in said
predetermined position with said inclined portions bearing against
each other to retain the shelf releasably in such position, and the
lower dwell portion of the cam surface on said supporting hub
frictionally engaging the upper dwell portion of the cam surface on
said cam when said shelf is rotated from said predetermined
position thereby to resist unduly free rotation of the shelf one
side of said post being deformed inwardly to define a depression
extending along the side of the post, each of said cams being
formed with a centrally located hole receiving said post an
inwardly extending key formed integrally with each cam adjacent
said hole and projecting into said depression, and a screw threaded
through each cam and bearing against the opposite side of said post
to draw said key tightly into said depression and thereby lock the
cam against rotation on the post.
2. A revolving shelf assembly as defined in claim 1 in which each
cam includes a cylindrical bushing formed integrally with and
projecting upwardly from said cam surface on said cam, said bushing
being telescoped over said post and into one of said supporting
hubs to mount the latter rotatably and slidably on the post.
3. A shelf assembly as defined in claim 1 in which each of said
cams comprises an inner supporting disc fastened to said post and
an outer sleeve made of plastic material telescoped over said disc
and defining the cam surface on said cam, said sleeve including a
cylindrical bushing formed integrally with and projecting upwardly
from said rise portions and said upper and lower dwell portions,
and said bushing being telescoped over said post and into one of
said supporting hubs to mount the latter rotatably and slidably on
the post.
Description
BACKGROUND OF THE INVENTION
This invention relates to a storage cabinet of the type which
includes a tier of revolving shelves mounted for rotation to
various angular positions within the cabinet to enable easy access
to articles on the shelves from an opening in the front of the
cabinet.
SUMMARY OF THE INVENTION
The general object of the invention is to provide novel detent
mechanisms capable of releasably retaining the revolving shelves in
normal centered positions in the cabinet and capable of resisting
unduly free rotation of the shelves when the latter are turned out
of their centered positions.
The invention also resides in the use of the detent mechanisms to
journal the shelves for rotation, in the unique arrangement of the
detent mechanisms to prevent looseness of the shelves after
continued service use and in the comparatively simple and
inexpensive construction of the detent mechanisms.
Other objects and advantages of the invention will become apparent
from the following detailed description taken in conjunction with
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a storage cabinet embodying the new
and improved features of the present invention.
FIG. 2 is a cross section taken substantially along the line 2--2
of FIG. 1 and showing the cabinet doors in open positions.
FIG. 3 is a fragmentary view similar to FIG. 2 but showing the
cabinet doors in closed positions.
FIG. 4 is an enlarged fragmentary cross section taken substantially
along the line 4--4 of FIG. 3.
FIG. 5 is an enlarged view of parts shown in FIG. 4 with certain
elements broken away and shown in section.
FIG. 6 is an enlarged cross section taken substantially along the
line 6--6 of FIG. 5.
FIG. 7 is a cross section taken substantially along the line 7--7
of FIG. 5.
FIG. 8 is a perspective view of a tray of the type adapted to be
mounted on the cabinet doors.
FIG. 9 is an enlarged fragmentary cross section taken substantially
along the line 9--9 of FIG. 4.
FIG. 10 is a fragmentary front elevational view of parts shown in
FIG. 9.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in the drawings for purposes of illustration, the
invention is embodied in a storage cabinet 15 having a tier of
vertically spaced shelves 16 which may be revolved individually
within the cabinet to various angular positions with respect to a
front access opening 17 to enable articles to be placed on or
removed from the shelves in any easy manner. Two upright doors 19
are hinged to the cabinet along opposite sides of the opening and
may be swung between positions opening and closing the cabinet.
Herein, the cabinet is substantially square in cross section and
includes top and bottom walls 20 and 21 interconnected by a front
wall 23, a rear wall 24 and a pair of sidewalls 25, the front wall
being formed by a series of narrow frame strips arranged in
rectangle to define the access opening 17. The doors are mounted on
hinges 26 attached to the front wall and each is approximately
equal in width to one-half the width of the opening so that the
latter is substantially covered when the doors are closed. Spanning
the top and bottom walls and attached to the latter by brackets 27
(FIG. 4) is an upright post 29 which rotatably mounts the revolving
shelves 16. In this instance, five such shelves are mounted on the
post and are spaced vertically from one another by equal
distances.
A tier of trays 30 are mounted on the inner side of each door 19
and are arranged relative to the shelves 16 to make effective use
of almost all of the available storage space in the cabinet and to
provide a relatively large total surface area for supporting
articles. For these purposes, the shelves 16 are sized, shaped and
located to leave a minimum of wasted space between the shelves and
the cabinet sidewalls 25 and the rear wall 24 and, at the same
time, to leave only enough room remaining in the front of the
cabinet to accommodate trays 30 of optimum depth when the doors are
closed. The trays are made sufficiently deep to fill most of the
space between the shelves and the front wall 23 of the cabinet but
not so deep as to interfere with the trays on the other door when
the doors are opened and closed. With this arrangement, the trays
and shelves leave little wasted space between the front, rear and
sidewalls of the cabinet so that relatively large surface areas for
supporting articles are provided within a cabinet of given
size.
In the present instance, five trays 30 are attached to each door 19
and each is aligned horizontally with a different one of the
revolving shelves 16. Each tray extends substantially across the
full width of its respective door and is of greater width w (FIG.
3) than depth d. Each tray is located on the door in such a manner
and is formed of such a depth d that the outboard corner 31 of each
tray lies approximately on but not beyond or outside of an arc a
extending about the axis of the hinges 26 of the door upon which
the tray is mounted and extending through the vertical free edge 33
of such door. As a result, the trays may be located near the
vertical edges of the doors and may be made of a maximum depth and
yet will not interfere and strike the trays on the other doors when
the doors are opened and closed either independently or
simultaneously.
With the trays 30 formed of an optimum depth d, the shelves 16 are
shaped and located to fill most of the space between the trays, the
sidewalls 25 and the rear wall 24 thereby to avoid wasting space
within the cabinet 15. To these ends, the supporting post 29 is
spaced equidistantly from the rear and sidewalls, herein being
located at the geometrical center of the square cabinet, and each
shelf is shaped as a partial circle having a diameter approximately
equal to but not greater than the width of the cabinet. In this
way, the arcuate periphery 34 of each shelf is located directly
adjacent the rear and sidewalls to provide the maximum shelf area
while still allowing turning of the shelf within the cabinet. As
shown most clearly in FIG. 2, each shelf 16 herein is slightly
larger than a three-quarters circle and is formed along one side
with a straight edge 35 which faces and extends parallel to the
doors 19 when the shelf is turned to a normal or centered position
in the cabinet. The straight edge 35 extends across a chord of the
circle defined by the arcuate periphery 34 of the shelf and is
spaced from the inner sides of the doors a distance approximately
equal to but not less than the depth d of the trays. With this
arrangement, the shelves encompass practically the largest possible
area of a circle capable of fitting into the cabinet, and the
straight edges 35 are located closely adjacent to but do not
interfere with the trays 30 when the doors are closed. Accordingly,
very little space is wasted since a substantial portion of a given
plane within the cabinet is filled with a tray and a shelf.
According to the primary aspect of the invention, provision is made
of novel detent mechanisms 36 (FIG. 5) for releasably holding the
shelves 16 in their normal centered positions and for resisting
unduly free rotation of the shelves when the latter are turned from
their centered positions. In this instance, each detent mechanism
comprises a stationary cam 37 anchored to the center post 29 and
coacting with a similar cam 39 on each shelf to latch the shelf in
its centered position. When the shelf is turned from its centered
position, the two cams frictionally bear against one another to
resist any tendency of the shelf to spin uncontrollably on the post
and to help hold the shelf in any position to which it is
turned.
More specifically, each cam 37 comprises an inner circular
supporting disc 40 (FIGS. 5 and 6) formed with a centrally located
hole 41 which receives the post 29. A sleeve 43 of Delrin or other
wear resistant plastic is telescoped over the disc and is formed
with a downwardly extending tongue 44 (FIG. 6) which is projected
downwardly into a notch 45 formed in the disc adjacent the hold 41.
Advantageously, the post 29 is formed from a tube of light gauge
metal and is deformed inwardly along one side to define a
depression 46 extending along the length of the post. To anchor the
cam 37 securely to the post, a key 47 (FIG. 6) is formed on the
disc adjacent the hole 41 and is projected inwardly into the
depression 46. A setscrew 49 extending inwardly through the sleeve
43 is threaded into the disc 40 and the tongue 44 and bears against
the side of the post opposite the depression 46 to draw the key 47
tightly into the depression and thereby rigidly anchor the cam 37
against rotation on the post.
Each cam 39 is formed on the lower end surface of a generally
frustoconical supporting hub 50 (FIGS. 4 and 5) fastened to the
underside of each shelf and formed with a centrally located bore 51
which loosely receives the post 29 to mount the shelf 16 both for
rotation and for up and down sliding on the post. The lower end of
the hub 50 and the upper side of the sleeve 43 are both formed with
cam surfaces which include a lower dwell portion 53 extending
around a short arc of the hub and the sleeve, a pair of rise
portions 54 inclined upwardly from the lower dwell portions at an
angle of about 45.degree., and an upper dwell portion 55 extending
between the ends of the rise portions and through a greater arc
than the lower dwell portions. When each shelf is disposed in its
centered position with its straight edge 35 facing the doors 19,
the upper and lower rise portions 53 and 55 of the sleeve 43 and
the hub 50 mate with each other as shown in FIG. 4 and, in
addition, the rise portions 54 engage one another to retain the
shelf releasably in its centered position so that the doors may be
closed. If the shelf is manually rotated in one direction or the
other, one of the rise portions 54 on the hub 50 cams against one
of the rise portions 54 on the sleeve 43 to cause the shelf to
slide upwardly on the post 29 and to free the shelf for rotation
away from its centered position. With continued rotation of the
shelf, the lower dwell portion 53 of the hub 50 rides along and
bears against the upper dwell portion 55 of the plastic sleeve 43
as shown in FIG. 5 and develops sufficient friction to retard
unduly free rotation of the shelf and to stop the shelf when the
manual turning force is removed. The shelf thus will tend to remain
in any position to which it is turned. As the shelf is returned to
its centered position, the rise portions 54 on the hub 50 ride
downwardly on and then bear against the rise portions 54 on the
sleeve 43 to latch the shelf once again in its centered position
and thus avoid any danger of the aligned tray 30 striking the
arcuate periphery 34 of the shelf when the doors are closed.
Preferably, a cylindrical bushing 56 (FIGS. 5 and 7) is formed
integrally with each plastic sleeve 43 and is telescoped over the
post 29 and into the bore 51 in the overlying hub 50. Each bushing
projects upwardly from the rise portions 54 and the upper and lower
dwell portions 53 and 55 of the sleeve and establishes a bearing
which serves to mount the shelf 16 slidably and rotatably on the
post. The lower half of the portion of the bushing 56 extending
upwardly from the lower dwell portion 53 of the sleeve is not
subjected to wear when the shelf is being turned through positions
other than its centered position and thus such lower half of the
bushing tends to retain its original diameter to insure that, even
after long service use, the shelf will not loosen up and tip on the
post when the shelf is disposed in its centered position. An
additional bushing 57 is telescoped into the bore 51 of the hub
just below the shelf and also helps to keep the shelf from becoming
loose on the post.
Advantageously, the trays 30 are hooked detachably on standards 60
fastened to the inner side of the doors 19 with the rear edges of
the trays lying directly alongside the doors so as to avoid leaving
objectionable gaps between the trays and the doors. As shown in
FIGS. 1, 9, and 10, two vertically extending and parallel standards
of U-shaped cross section are fastened to the inner side of each
door and each is formed with a series of vertically spaced holes or
slots 61 in its forward face for receiving hooks 63 on the trays.
Each tray includes a substantially rectangular sheet metal shelf 64
(FIG. 8) which is formed with an upturned rim 65 along its front
margin and with side panels 66 turned upwardly from its side
margins. Two of the hooks 63 are formed on the rear edge 67 of each
side panel 66 and are adapted to project into one of the pairs of
slots 61 in the standards 60 to attach the tray to the door, the
rear edges of the panels abutting the front faces of the standards
in the installed position of the tray. Preferably, the side panels
and side margins of each tray are inclined toward one another at a
slight angle so that the depth d of the tray shelf 64 may be
increased while still keeping the outboard corner 31 located within
the arc a to avoid interference with the trays on the other
door.
As shown most clearly in FIGS. 8 and 9, the rear margin 70 of each
tray 30 is turned upwardly from the plane of the tray shelf 64 and
is disposed directly alongside the inner side of the door 19 in a
position located rearwardly or inwardly of the forward faces of the
standards 60. To enable such close positioning of the rear margin
70 of the tray to the door, squared notches 71 are formed in the
rear corners of the tray shelf and are of a depth corresponding to
the depth of the standards to allow the rear margin to project past
the standards and to allow the rear edges 67 of the side panels 66
to abut the forward faces of the standards. Thus, the rear margins
70 of the trays lie alongside the doors instead of extending along
the forward faces of the standards and creating gaps of
objectionable width between the trays and the doors.
* * * * *