U.S. patent number 3,879,796 [Application Number 05/408,496] was granted by the patent office on 1975-04-29 for bed stabilizing assembly.
This patent grant is currently assigned to Standex International Corporation. Invention is credited to Albert J. Whyte.
United States Patent |
3,879,796 |
Whyte |
April 29, 1975 |
BED STABILIZING ASSEMBLY
Abstract
A device for braking and positively stabilizing a bed which
normally rides on casters. The device includes a cam actuated
extension of each of the bed legs which lift the bed sufficiently
to clear the casters from the floor.
Inventors: |
Whyte; Albert J. (Springfield,
MA) |
Assignee: |
Standex International
Corporation (Andover, MA)
|
Family
ID: |
23616517 |
Appl.
No.: |
05/408,496 |
Filed: |
October 23, 1973 |
Current U.S.
Class: |
5/510; 5/620;
248/188.5; 5/617; 16/33 |
Current CPC
Class: |
A61G
7/00 (20130101); B60B 33/0089 (20130101); A61G
7/0528 (20161101); A47B 91/02 (20130101); Y10T
16/1937 (20150115) |
Current International
Class: |
A47B
91/00 (20060101); A47B 91/02 (20060101); A61G
7/00 (20060101); B60B 33/00 (20060101); A61G
7/05 (20060101); A47c 021/00 () |
Field of
Search: |
;5/328,63,86
;248/188.5,188.2 ;16/33,32 ;403/81 ;74/531 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: McCall; James T.
Assistant Examiner: Marquette; Darrell
Attorney, Agent or Firm: Weingarten, Maxham &
Schurgin
Claims
What is claimed is:
1. A bed stabilizing assembly for each leg of a bed, the bed
normally resting upon casters relatively adjacent each leg, said
stabilizing assembly comprising:
a sleeve slidingly surrounding the bottom end of said leg, said
sleeve having an opening in one side thereof formed of a plurality
of interconnected flat edges, the edges of said opening acting as a
cam follower;
a cam having a plurality of mutually perpendicular flat sides
adapted to bear against said edges of said opening, said cam being
pivotally mounted to one side of said leg and positioned within
said opening in said sleeve; and
means for rotating said cam;
whereby when said cam is rotated in one direction, said sleeve is
formed downwardly so as to make contact with the floor and to lift
the adjacent caster off the floor, and when such cam is rotated in
the opposite direction, said sleeve is forced upwardly permitting
said bed to rest on the caster.
2. The bed stabilizing assembly recited in claim 1 wherein said cam
rotating means comprises an elongated lever keyed to said cam and
pivotally mounted to said one side of said leg.
3. The bed stabilizing assembly recited in claim 1 wherein said
opening in said sleeve is substantially rectangular.
4. The bed stabilizing assembly recited in claim 3 wherein said cam
has two pairs of mutually perpendicular straight sides, one pair of
which fits flat against two sides of said opening in said sleeve
when said sleeve is in the downward position, and the other pair of
which fits flat against two sides of said opening in said sleeve
when said sleeve is in the upward position.
5. The bed stabilizing assembly recited in claim 4 wherein each
pair of mutually perpendicular straight sides are separated by a
curved surface and the center of said pivot is located on a line
normal to said straight sides and offset from said curved
surfaces.
6. The bed stabilizing assembly recited in claim 2 and further
comprising:
a T-nut secured to and extending outwardly from said one side of
said leg;
a bushing surrounding said T-nut; and
a screw securing said cam and said lever to said T-nut, said cam
and said lever fitting over the circumference of said bushing.
7. The bed stabilizing assembly recited in claim 6 and further
comprising a button projecting outwardly from said cam, said lever
having a hole displaced from said screw and engaging said button to
key said lever to said cam for rotation therewith.
8. The bed stabilizing assembly recited in claim 1 and further
comprising an end cap secured to the bottom end of said sleeve and
making contact with the floor when said sleeve is in the downward
position.
9. A bed stabilizing assembly for each leg of a bed, the bed
normally resting on casters relatively adjacent to each leg, said
stabilizing assembly comprising:
a sleeve slidingly surrounding the bottom end of said leg, said
sleeve having a substantially rectangular opening in one side
thereof, the edge of said opening acting as a cam follower:
a cam pivotally mounted to one side of said leg and positioned
within said opening of said sleeve, said cam having two pairs of
mutually perpendicular straight sides; and
an elongated lever keyed to said cam and pivotally mounted to said
one side of said leg;
whereby when said cam is rotated in one direction, said sleeve is
forced downwardly so as to make contact with the floor and to lift
the adjacent caster off the floor wherein one pair of said straight
sides of said cam fit flat against two sides of said opening in
said sleeve thereby locking said sleeve in the downward position,
and when said cam is rotated in the opposite direction, said sleeve
is forced upwardly permitting said bed to rest on the caster
whereby the other pair of said straight sides of said cam fit flat
against two sides of said opening in said sleeve thereby locking
said sleeve in the upward position.
Description
FIELD OF THE INVENTION
This invention relates generally to beds and more particularly to a
device for stabilizing beds which normally ride on casters.
DISCUSSION OF THE PRIOR ART
Many types of beds, especially invalid or hospital beds, are
normally made to ride on casters so that they may easily be moved
about as required for patient use. However, when a patient is using
the bed, and especially when a patient gets into or out of the bed,
it is important that the bed be immobile.
Previously, many such beds have been fitted with caster locks which
are intended to prevent the casters from rolling. However, these
have not been completely satisfactory because they are not
positively stable, particularly because the casters may still
swivel and permit sufficient motion so as to be dangerous for a
patient who is trying to brace himself against the bed. Another
device which lifts the bed and the casters off the floor is shown
in U.S. Pat. No. 3,676,881. This combines a bed stabilizing
mechanism with a Trendelenburg or Fowler bed adjusting mechanism.
However, while the bed shown in this patent may be moved to
different heights, it may be stabilized only when it is in its
lowest position. It is obvious that one may wish to have the bed
stabilized when it is in other than its lowest position.
SUMMARY OF THE INVENTION
The novel device of this invention is a cam actuated sleeve
extending over the bottom portion of each leg of a bed so that the
bed can be raised by means of a cam actuating lever to such a
degree that casters which may be mounted to cross bars between the
end legs are raised off the floor and the bed thus stabilized. This
is completely independent of any other operation of the bed so that
the bed may be in the high or low position or in any intermediate
position permitted by the various bed mechanisms. The cam is
constructed in such a way that when the leg sleeve is in either its
upper or lower position with respect to the end of the bed leg, it
is locked in place such that it cannot be accidentally dislodged.
By means of this invention, a bed may be positively stabilized
completely independently of the casters or any other bed mechanism
and there will be no danger of the bed accidentally moving when it
is least desired.
BRIEF DESCRIPTION OF THE DRAWING
The features and advantages of this invention will become apparent
from the detailed description taken in conjunction with the drawing
in which:
FIG. 1 is a perspective schematic view of a bed having the
stabilizing device of this invention mounted on each of its
legs;
FIG. 2 is a side view of the stabilizing device of the present
invention; and
FIG. 3 is a sectional view taken through cutting plane 3--3 of FIG.
2, showing the details of the elements comprising the
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawing, FIG. 1 shows a bed 11 in
somewhat schematic form having legs 12, cross bars 13 between legs
12 at the ends of the bed, and casters 14 extending downwardly from
the cross bars. The top of the bed may have any desired
configuration and may be equipped with raising and lowering or
tilting mechanism actuated by typical crank 15. The bed shown in
FIG. 1 is in its normal position, resting upon casters 14 with the
bottoms of legs 12 clear of the floor. Each leg is equipped with
the stabilizing assembly 16 of this invention.
With reference now to FIGS. 2 and 3, there is shown the elements of
the invention in detail. Sleeve 17 is fitted over the lower portion
of leg 12 for limited longitudinal motion thereon. The sleeve is
shown completely surrounding the leg but it may have a gap in one
side if desired to facilitate manufacture thereof. The sleeve has a
rubber or plastic end cap 18 which protects the floor and also
serves as a frictional member for engaging the floor when the
sleeve is in its lowered position, wherein the casters are raised
from the floor. It should be noted that in FIGS. 2 and 3, sleeve 17
is shown in its stabilizing or lowered position. Welded in a hole
in one side of leg 12 and extending outwardly therefrom is T-nut 21
having internal threads. A bushing 22 which may be made of steel or
a suitable lubricating plastic, such as nylon, surrounds that
portion of the T-nut extending outwardly from the surface of the
leg. Cam 23 and cam actuating lever 26 are pivotally fitted over
the bushing and they are both secured to the T-nut by means of a
screw 24, shown as having a Phillips head, with a washer 25 located
between the screw head and the end of the T-nut. Cam actuating
lever 26, which is mounted outwardly of cam 23, is keyed thereto by
means of button 27 which projects from the outer surface of cam 23
through a hole 31 in lever 26 which is spaced from screw 24. Button
27 may be simply formed by punching some of the material from the
back side of the cam, as shown in FIG. 3. Sleeve 17 is formed with
a substantially square opening 32 which acts as the cam follower in
this device. The cam has four flat sides, two adjacent ones of
which are operative when the sleeve is in the raised position and
two adjacent ones of which are operative when the sleeve is in the
lowered position. The cam has rounded corners as necessary for
proper operation.
With respect to FIG. 2, when the right side of cam actuating lever
26 is pressed downward, the cam rotates clockwise forcing sleeve 17
downward with respect to leg 12 until flat surface 33 comes to rest
on inner edge 34 of opening 32 in the sleeve. Coincidentally, flat
surface 35 of the cam also rests against edge 36 of the opening in
the sleeve. In rotating clockwise to raise the leg of the bed, the
curved surface 43 between flat surfaces 33 and 35 of cam 23 bears
increasingly against inner edge 34 of the opening in the sleeve.
That is, the point at which the curve joins surface 33 is farther
from pivot screw 24 than is any other point on the curve. It should
be observed that the pivot point is located directly above flat
surface 33 as shown in FIG. 2, rather than above a portion of curve
43. This insures that the sleeve is locked in place and cannot be
dislodged to drop the bed onto the casters by vibration or any
force other than a positive counter-clockwise torque acting upon
cam 23.
To lower the bed onto a caster, that is, to raise sleeve 17 from
the floor, the left end of cam actuating lever 26 is pressed
downward and cam 23 is caused to rotate counterclock-wise about
screw 24. When that motion is accomplished, edge 37 of the cam
seats firmly against edge 41 of the opening in the sleeve, and edge
42 of the cam seats against inside surface 36 of the opening in
sleeve 17. At this time, the same type of positive positioning has
taken place and it is extremely unlikely that sleeve 17 would
become dislodged and drop down so that it touches the floor without
applying positive pressure to lever 26 to rotate the cam clockwise.
The same relationship exists between the pivot point and curve 44
as between the pivot point and curve 43, thus assuring that the
sleeve remains locked in position.
Curve 45 of the cam between flat surfaces 35 and 42 is essentially
concentric with the pivot point and lightly contacts or just clears
inside edge 36 of the opening in the sleeve. Curve 46 between flat
surfaces 33 and 37 of the cam is also substantially concentric with
the pivot and it permits clearance of the cam when it rotates so
that there is no interference with the inside edges of opening 32
in the sleeve.
It may thus be easily seen that by simply stepping on one side of
each of the four cam actuating levers on the legs of the bed, the
entire bed is raised off the casters and is positively stabilized
on the floor, completely independently of any other bed mechanism.
While the casters are shown attached to a cross bar, that is not
necessary and they may be mounted in any desired manner so as to be
fixed relative to the legs. It is likely that modifications and
improvements will occur to those skilled in the art which are
within the scope of this invention.
* * * * *