US 3879796 A
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.
Description (OCR text may contain errors)
United States Patent [1 1 [111 3,879,796
Whyte Apr. 29, 1975  BED STABILIZING ASSEMBLY 2,888,707 6/l959 Warrick, et al 16/33 3. 7 l 7 I972 D  Inventor: Albert J. Whyte, Springfield. Mass. 6 6 88 I prey 5/63  Assignee: itacriidex lnrt/frnational Corporation, Primary Emminer james T McCall n Over Assistant E.\'aminer Darrell Marquette  Filed: Oct. 23, 1973 Attorney, Agent, or Firm-Weingarten, Maxham & 211 App]. No.: 408,496 Schurgm  US. Cl. i. 5/328; 5/63; 5/86; . ABSTRACT 16/33; 248/1885  Int. Cl. A47c 21/00 A device r raking and positively tabilizing a bed  Field f S rch H 5/328, 63, 86; 248/1885 which normally rides on casters. The device includes a 248/1882; 16/33, 32; 403/81; 74/531 cam actuated extension of each of the bed legs which lift the bed sufficiently to clear the casters from the References Cited floor.
UNITED STAT P ES ATENTS 9 Claims, 3 Drawing Figures 343,5ll 6/l886 White 16/33 BED STABILIZING ASSEMBLY 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 US. 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 33 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.
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.