US3581319A - Electrically operable bed - Google Patents

Abstract

ELECTRICALLY OPERABLE BED HAVING FRAME, HI-LOW DRIVE MEANS FOR MOVING FRAME VERTICALLY, ARTICULATED SPRING WITH INTERMEDIATE, HEAD, KNEE AND FOOT SECTIONS, DRIVE MEANS FOR RAISING AND LOWERING HEAD AND KNEE SECTIONS, ELECTRIC MOTOR, TRANSMISSION MEANS MOUNTED ON FRAME FOR EFFECTING ACTUATING OF DRIVE MEANS BY MOTOR, GEAR REDUCER AND CLUTCH INTERPOSED BETWEEN MOTOR AND TRANSMISSION MEANS, FUNCTION SELECTOR MEANS MOUNTED ON FRAME FOR SELECTIVELY DETERMINING WHICH DRIVE MEANS WILL BE ACTUATED BY TRANSMISSION MEANS INCLUDING A KEY ROTATABLE BY THE MOTOR AND AXIALLY SLIDABLE TO EFFECT SELECTION, AND RUBBER-CUSHION MOUNTING OF MOTOR ON FRAME INCLUDING BOLTS DISPOSED PARALLEL TO AXIS OF ROTATION OF KEY TO FACILITATE EASE OF SELECTIVE AXIAL MOVEMENTS TO OF KEY. ALSO INCLUDES MOVEMENTLIMITING MEANS INTERPOSED BETWEEN HEAD AND KNEE SECTIONS NORMALLY DOWNWARD MOVEMENT OF OUTER ENDS OF HEAD AND PREVENT DOWNWARD MOVEMENT OF OUTER ENDS OF HEAD AND KNEE SECTIONS BELOW HORIZONTAL AND SELECTIVELY MOVABLE TO PERMIT RAPID PLACING OF SPRING IN TRENDELENGURG, REVERSE TRENDELENBURG, OR HYPEREXTENSION POSITIONS, COM-

PRISING LEVELERS HAVING NORMALLY VERTICALLY DEPENDING ARMS PIVOTALLY MOUNTED ON HEAD AND KNEE SECTIONS AND EACH HAVING FOOT MEANS ENGAGEABLE WITH FRAME, AND NORMALLY INOPERATIVE LEVELERS LATCHES PIVOTALLY MOUNTED ON HEAD AND KNEE SECTIONS AND MANUALLY SWINGABLE TO OPERATIVE POSITION TO CAM ASSOCIATED LEVELER ARM TO, AND RETAIN SAME IN, NON-VERTICAL INOPERATIVE POSITION, SUBSEQUENT DOWNWARD SWINGING OF HEAD OR KNEE SECTION CAUSING ENGAGEMENT OF LEVELER WITH FRAME TO RELEASE LATCH FOR AUTOMATIC RETURN TO NORMAL INOPERATIVE POSITION, AND THE MOVEMENTLIMITING MEANS ALSO INCLUDING FOOT SECTION SUPPORT MEANS PIVOTED AT INNER END ON FRAME AND HAVING TRANSVERSELY EXTENDING PIN AT OUTER END COOPERATIVELY ENGAGING RATCHET BRACKET MOUNTED ON FOOT SECTION.

Description

June1,1971 J,F,STAN| EY Em. 3,581,319

ELECTRICALLY OPERABLE BED Filed April 4, 1969 3 Sheets-Sheet l 5 Sheets-Sheet 1;

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J. F. STANLEY ETAL ELECTRICALLY OPERABLE BED June 1, 1971 il n \\m.w D wm F m O @N m 1 I LI?, I,I:-H Il v .1H :H11 I LU iii@ -QT M m W /H/ Vi MM. m 9 m 6 9 H l H 4. l 1 m n m. d e l i F June l, 1971 J, F, STANLEY ETAL 3,581,319

ELECTRIGALLY OPERABLE BED 3 Sheets-Sheet Z5 Filed April 4, 1969 United States Patent O 3,581,319 ELECTRICALLY OPERABLE BED John F. Stanley and Barron .1. Gulliver, Stevens Point, Wis., assignors to Joerns Furniture Company, Stevens Point, Wis.

Filed Apr. 4, 1969, Ser. No. 813,647 Int. Cl. A61g 7/:00, 7/10 U.S. Cl. --68 10 Claims ABSTRACT 0F THE DISCLOSURE Electrically operable bed having frame, hi-low drive means for moving -frame vertically, articulated spring with intermediate, head, knee and foot sections, drive means for raising and lowering head and knee sections, electric motor, transmission means mounted on frame for effecting actuation of drive means by motor, gear reducer and clutch interposed between motor and transmission means, function selector means mounted on frame for selectively determining which drive means will be actuated by transmission means including a key rotatable by the motor and axially slidable to effect selection, and rubber-cushion mounting of motor on frame including bolts disposed parallel to axis of rotation of key to facilitate ease of selective axial movements of key. Also includes movementlimiting means interposed between head and knee sections of normally horizontal spring and frame operable to prevent downward movement of outer ends of head and knee sections below horizontal and selectively movable to permit rapid placing of spring in Trendelenburg, reverse Trendelenburg, or Hyperextension positions, cornprising levelers having normally vertically depending arms pivotally mounted on head and knee sections and each having foot means engageable with frame, and normally inoperative levelers latches pivotally mounted on head and knee sections and manually swingable to operative position to cam associated leveler arm to, and retain same in, non-vertical inoperative position, subsequent downward swinging of head or knee section causing engagement of leveler with frame to release latch for automatic return to normal inoperative position, and the movementlimiting means also including foot section support means pivoted at inner end on frame and having transversely extending pin at outer end cooperatively engaging ratchet bracket mounted on foot section.

BACKGROUND OF THE INVENTION Field of the invention This invention relates generally to hospital beds, and more particularly to those selectively operable electrically under the control of the using patient to raise and lower the latter and the pivotally swingable head and knee sections of an articulated spring.

Description of the prior art In U.S. Letters Patent No. 3,281,873, a manually operable hospital bed disclosed which includes a frame, hi-low drive means for raising and lowering the frame, an articulated spring mounted on the frame having intermediate, head, knee and foot sections, drive means for raising and lowering the head and knee sections, a single manually operable crank, and a function selector for selectively determining which of the three drive means will be operated when the crank is rotated. Basically similar such mechanisms are provided with an electric motor drive and relatively complex transmission, function and motor control means in U.S. Letters Patent No. 3,414,913.

Patented June l, 1971 SUMMARY oF THE rNvENTIoN The present invention provides an electrically operable bed embodying greatly simplified transmission and control means enabling use of a motor in an inexpensive structure which, nevertheless, is shock-proof and free of malfunctioning problems. As compared to the more complex mechanisms of No. 3,414,913, for example, the present invention minimizes use of drive gears, employing sprocket wheels and chains, and eifects ease of operation of the axially slidable function selector by means of rubber-cushioned mounts for the motor and reduction gear box, including mounting bolts disposed substantially parallel to the axis of the function selector. Without such flexible motor mounting, it would be difficult to move the selector drive key axially to make the desired function selection. And by employing a gear reducer and clutch between the motor and the transmission means, stalling or a locked rotor condition is not imposed upon the motor when a function operation is terminated automatically by a positive limiting stop. This invention also incorporates novel interconnections between the head and knee sections of the spring and the frame to facilitate placing of the spring in Trendelenburg, reverse Trendelenburg, and Hyperextension positions.

In the drawings:

FIG. 1 is a plan view, with parts broken away, of a bed embodying the features of the invention;

FIG. 2 is an enlarged detail vertical section through the function selector taken substantially on the line 2 2 of FIG- 3;

FIG. 3 is a detail plan view similar to FIG. l on a larger scale of the transmission, drive and control mechanisms;

FIG. 4 is a detail plan of the interconnections between the outer end of the foot section support and the ratchet bracket on the foot section;

FIG. 5 is a side elevation of the mechanism of FIG. 4;

FIG. 6 is a detail vertical section taken substantially on the line 6-6 of FIG. 5;

FIG. 7 is an exploded plan view of one end of the head section leveler and latch;

FIG. -8 is a side elevation of the mechanism of FIG. 7 with the parts shown in full lines in normal position and in broken lines with the leveler latched in inoperative position; and

FIG. 9 is a detail vertical section through one of the cushion mounting means for the motor.

DESCRIPTION OF PREFERRED EMBODIMENT Referring more particularly to FIG. 1, the illustrated bed of this invention includes a frame, indicated generally by reference numeral 11, supporting means for the frame including four legs 12, and a normally horizontally disposed, articulated spring, generally designated 13, mounted on the frame 11 and comprising an intermediate or Seat section 14 rigidly secured to the frame, a head section 1S pivotally connected to the intermediate section at 16, a knee section 17 pi-voted to 14 at 18, and a foot section 19 pivotally connected at 21 to the knee section 17. The frame 11 includes side rails 22, and rigid transverse members comprising outer and inner gear box plates 23 and 24 and a bearing frame plate 25.

Hi-low drive means are provided for raising and lowering the frame 11 and spring 13 relative to the supporting legs 12 which are similar to those of U.S. Letters Patent No. 3,281,873 and include a hi-lofw screw 26 (FIGS. 1 and 3) mounted in suitable thrust bearings carried by the inner gear box plate 24 and frame plate 25 and cooperating at its inner end with drive release brake means 27 (FIG. 3) similar to such means disclosed in U.S. Letters Patent No. 3,281,872. The screw 26 is engaged by a nut 28 constrained in well-known manner against rotation and slidably mounted for longitudinal movement relative to the frame 11. Secured to the nut 28 are the ends of two pairs of cables 29 and 31 (FIG. 1) the former of which extend toward the head of the bed, around suitable guide sheaves 32 and 33 and are secured to the upper ends of the head end legs 12. The other cables 31 extend forwardly to and around guide sheaves 34 and rearwardly therefrom and over similar guide sheaves 32 and 33 for attachment to the upper ends of the foot legs 12. Consequently, rotation of screw 26 results in raising or lowering of the frame 11 and spring 13 relative to their supporting means 12.

Head section drive means also are provided for raising and lowering the head section of the spring about its pivots 16 relative to the frame 11 which include a head screw 35 mounted in the frame plates 2.4 and 25 in similar manner to the hi-low screw 26 (FIG. 3), a nut 36 thread edly engaging the screw, and forwardly extending, parallel links or rails 37 connected at their rear ends to the screw 35. As shown in FIG. l, the forward ends of these rails 37 are pivotally connected to level or crank arm means 38 secured to a transverse crank shaft 39. With this arrangement, rotation of the screw 35 will cause translation of the nut 36 and the links 37 connected thereto to rotate the crankshaft 39 through the agency of the crank arm means 38 to swing the head section 15 up or down about its pivots 16.

Knee section drive means of similar construction also are provided for raising and lowering the knee section 17 about its pivots 18 relative to the frame 11 which include a knee screw 41 (FIGS. l and 3) mounted in the frame plates 24 and 25 in similar manner to the screws 26 and 35, a nut 42 threadedly engaging the same, and forwardly extending links or rails 43 connected at their rear ends to the nut 42. The forward end portions of these rails are pivotally connected to crank arm means 44 which, in turn, are secured to a transverse crank shaft 45 depending from the inner end portion of the knee section 17. Rotation of the screw 41 thus will be transmitted through the nut 42, links 43, crank arm means 44 and crankshaft 45 to the knee section 17 to swing the same vertically about its pivots 18. It will be appreciated that this hi-low, head section and knee section drive means are arranged and operate similarly to the comparable parts disclosed in No. 3,281,873.

Rather than being manually operable as in that patent, these three drive means are adapted to be selectively actuated by an electric motor 46 through the agency of transmission means mounted betwen the outer and inner gear box plates 23 and 24, as best seen in FIG. 3. This transmission means includes a sprocket wheel -47 secured to the outer end of a shaft comprising an extension of the hi-low screw 26 drivingly connected by a chain 48 with an intermediate drive sprocket 49. Similarly, a sprocket wheel 51 is mounted on an outer extension of the head section screw 35 and drivingly connected by a chain 52 with an outer drive sprocket 53. The knee screw 41 is driven by a gear 54 secured to an outer extension thereof which meshes with a driving gear 55. As best seen in FIG. 2, the driving sprockets 49 and 53 and this driving gear 55 are co-axially mounted for individual rotation on a drive tube 56 which is secured to front and rear plugs 57 and 58 journaled in any suitable manner, respectively, in the inner and outer gear box plates 24 and 23. These sprockets 49 and 53 and the gear 55 are separated by suitable washers 59 and the assemblage thereof is retained against axial displacement on the drive tube 56 by rings 61 engaging in annular grooves in the outer surface of the drive tube.

Slidably disposed in a suitable bore in the front plug 57 is a key carrier 62, the inner end of which is disposed within the drive tube 56 and shaped to slidably retain a drive key 63. The outer or active end of this key 63 Slidably extends through a slot 64 in the drive tube 56 so as to be driven rotationally thereby. The inner end of the key 63 is provided with a slot or recess guidingly engaging a spring 65, the outer end of which engages a detent ball 66 movable in a suitable aperture in the key carrier 62 and urged by the spring 65 axially outwardly into engagement with the bore of the drive tube 56. The latter is provided with a centrally disposed recess 67 opposite the slot 64 to receive the ball 66 when the key carrier and the key 63 are in their longitudinally central position of FIG. 2.

Each of the sprockets v49 and 53 and the driving gear 55 is provided with a keyway 68 which is engageable by the outer end of the key 63, and longitudinal movements of the key carrier 62 will selectively determine with which of the sprockets 49 or 53 or gear 55 the driving key 63 wil lbe engaged. In the position of the instant drawings, key 63 is engaged in the keyway 68 of the intermediate drive sprocket 49 so that rotation of the drive tube 56 will be transmitted only to that sprocket 49 for rotating the hi-low screw 26. If the key carrier 62 is moved to the left from its position of FIG. 2, the key 63 will rst be cammed inwardly by virtue of its curved outer end contacting the washer 59 between the sprockets 49 and 53, and then will be engaged with the key-way 68 in the outer drive sprocket 53 by the spring 65. In this outer position of the key carrier 62, rotation of the drive tube 56 will be transmitted by the drive sprocket 53 to the head section screw 35. Similarly, movement of the key carrier 62 inwardly or to the right from its position of FIG. 2 will result in driving engagement of the key 63 with the gear 55, whereby subsequent rotation of the drive tube 56 will be transmitted to the knee screw 41.

Such selective positioning of this function selector means is accomplished manually in the following manner. The forward end of the key carrier 62 is secured, as shown in FIG. 3, by a shift sleeve 69 and a plug extension 71 connected to the sleeve to the rear end of a shift rod 72, as by means of cotter pins. As shown in FIG. l, the forward end of this shift rod 72 is suitably connected at 73 to a transverse rod 74 rotatably mounted in and extending outwardly through the side frames of the intermediate section 14 of the spring 13. Suitable manually operable control members 75 and attached to the outer ends of this transverse rod 74, so that selective positioning of the function selector key 63 may readily be effected from either side of the bed by a patient thereon or an attendant next to the bed.

Operation of the motor 46 is controlled by suitable manually operable control members 76 located adjacent the selector control members 75 and connected to a transverse rod 77 journaled like the rod 74 in the side frames of the intermediate spring section 14. The transverse rod 77 is suitably interconnected at 78 (FIG. l) to the forward end of a switch rod 79 which extends rearwardly through an aperture in the bearing frame plate 25. As best seen in FIG. 3, washers and stop rings 81 are mounted on this switch rod 79 at each side of, and adjacent to, the vertical web of the frame plate 25, and a coil spring 82 is mounted on the rod and interposed between the frame plate 25 and each of these stop rings 81. With this arrangement, the switch rod 79 is resiliently retained in an intermediate inoperative position. The outer end of the rod 79 is provided with a switch actuator disk 83 disposed in such inactive position of the rod between the switch actuating levers of two micro-switches 84 and 85, that are mounted in any suitable manner within the gear box defined by the plates 23, 24. These switches 84 and 85 are connected in well-known manner in the circuit of the motor 46 so that closing of the switch 84 energizes the motor, and closing of switch 85 causes reverse reverse rotation of the motor 46. Consequently, when either of the motor control members 76 is swung forwardly or toward the head of the bed, the rod 79 will be moved from its normal inactive position outwardly or to the left in FIG. 3 to close the normally open switch 84 to cause rotation of the motor 46 in one direction, while movement of either of the control members 76 toward the foot of the bed will result in the rod 79 being moved inwardly to close the normally open switch 85 to cause rotation of the motor 46 in the opposite or reverse direction. It will be appreciated that the motor will remain energized only so long as one of the control members 76 is manually retained in either such actuated position, and that release of the control members will result in one or the other of the springs 82 returning the rod 79 and its switch actuator disk 83 to normal inactive position to de-energize the motor.

The motor 46 comprises part of the actuating unit which also includes reduction gearing and a gear reducer and clutch driven thereby and housed in a gear box 86 mounted with the motor on a mounting plate 87 (FIG. 3) inwellknown manner, the driving shaft of the gear box 86 being connected in any suitable way to the rear plug 58 of the function selector and drive means. To assure proper operation of the function selector control or key carrier 62 and key 63, cushion mounting means are interposed between the motor and the bed frame 11 which comprises a plurality of pairs of mounting bolts 88 and 89 `disposed substantially parallel to the axis of rotation of the drive key 63 and its carrier 62. As best seen in FIGS. 3 and 9, the heads of each aligned pair of bolts 88, 89 are embedded in and retentively cemented to a suitable rubber cushioning member 90, with the outer ends of the bolts threaded into tapped apertures in the mounting plate 87 and their inner ends extending through suitable apertures in the outer gear box plate 23 with retaining nuts 91 mounted thereon for securing the mounting plate 87 to plate 23.

As previously noted, the several sections of the articulated spring 13 normally are disposed in a horizontal position parallel to the frame 14, and upward swinging of the head section 15 about its pivots 16, the knee section 17 about its pivots 18, and the resulting raising of the foot section 19 by its pivots 21 may be accomplished selectively by operation of a motor control member 76 following selective adjustment of the drive key 63 into engagement with either the sprocket 53 or the gear 55, respectively, by means of one of the function selector control members 75. Likewise, reverse operation of the motor will move those spring sections downwardy. Movement-limiting means are disposed between the head section 15 and the frame 14 and between the knee section 17 and the frame 14 which normally are operable to prevent downward movement of the outer ends of the head and knee sections below normal horizontal position and are selectively movable to permit placing of the spring in Trendelenburg, reverse Trendelenburg and Hyperextension positions.

Referring to FIG. l, movement-limiting means also are provided for the foot section 19 which comprises a pair of foot support arms 92 pivotally connected at their lower, inner ends at 93, to the respective side rails 22 of the frame 11. The outer end of each of these arms 92 is secured in any suitable manner, as by welding, to a foot support cross-tube 94. As best seen in FIGS. 4-6, each of the ends of this tube 94 is rigidly connected to the lower end of a bracket 95 which carries at its upper end an outwardly extending foot ratchet pin 96. Mounted under each of the side rails of the foot section 19 is a ratchet bracket 97 adapted to cooperate with the associated pin 96. As best seen in FIG. 6, each bracket 97 is U-shaped in transverse section, with the outer wall secured, as by welding, to the depending flange of the associated side rail of the foot section 19. The inner side wall of each bracket 97 is spaced downwardly from the horizontal portion of the foot section frame 19 and is formed to provide a plurality of longitudinally spaced ratchet teeth 98 for selective engagement by the associated pin 96. As best shown in FIG. 5, each ratchet 97 is further provided with an upward extension at its outer end defining a recess 99 spaced above the bottom portions of the teeth 98. It will be appreciated that the two brackets 97 on opposite sides of the foot section 19 are formed complementally to each other.

As the knee section 17 ofthe spring 13 is swung upwardly about its pivots 18, the pivots 21 will be raised and moved toward the head of the bed to carry the inner end of the foot section 19 in that direction with them. This will result in movement of the ratchet brackets 97 to the right in FIGS. 1, 4 and 5, and because of the engagement of the ratchet pins 96 therewith, such moving force will be exerted against those pins and the foot support arms 92. Because of engagement of the ratchet pins 96 in the base of selected ratchet teeth v98 and the: pivotal connections 93 of the arms 92, continued upward swinging of the knee section 17 will also result in raising of the outer end of the foot section 19, although to a lesser degree. Engagement of the pins 96 with a different set of ratchet teeth to determine a relatively higher positioning angularly of the foot section 19 with respect to the knee section 17 and the frame 11 about pivots 21 may then be effected to retain the foot section in such higher angular position. Selective adjustment of the pins 96 into engagement with different ones of the ratchet teeth 98 or 99 may readily be effected by applying upward pressure manually simultaneously to the foot section 19 and the foot support members 92, 94, to disengage the pins 96 from the ratchet teeth and, while maintaining the pins 96 above the teeth 98, moving the foot section 19 to the desired position and releasing the foot support members to allow the pins 96 to fall into engagement with the selected ratchet teeth. It will be understood that such adjustment may be employed also to permit lowering of the foot section 19 below horizontal to dispose the pins `96 in the end recesses 99 of the ratchet brackets. It will be appreciated that during any permitted lowering of the knee section 17, the ratchet pins 96 will not become disengaged from under the ratchet teeth `98 with which they are then associated because of the overhang of those teeth, and that downward movement of the foot section 19 relative to the frame 11 thus will be limited by this foot support mechanism and the knee section 17. Positioning of the ratchet pins 96 in the end recesses 99 of their associated ratchet brackets 97 to enable placement of the spring in Trendelenburg position will result in downward movement of the foot section 19 being limited by contacting of the side rails 22 of the frame 11 by the foot support cross-tube 94.

For limiting the downward movement of the head section 15 of the spring 13 relative to the frame 11, a transversely extending leveler tube 101 (FIG. 1) is pivotally connected at its up-turned ends to the side frame of the head section so as normally to depend substantially vertically therefrom in response to gravity. Thus, as the head section 15 is swung downwardly about its pivots 16, the foot portion or lower transverse section of this leveler tube 101 will come into contact with the upper surfaces of the side rails 22 of the frame 11 to limit such downward movement of the head section. When it is desired to put the spring 13 into reverse T rendelenburg position, however, it is necessary to lower the outer end of the head section 15 below such normal position. To this end, the present invention includes novel means for moving the leveler tube 101 angularly from such normal depending and substantially vertical position to an inoperative position and latching the same therein so that subsequent operation of the head screw 35 by the motor 46 may be employed t0 swing the head section further downwardly.

As best seen in FIGS. 7 and 8, the upper end portions of the leveler tube 101 are pivotally connected to the associated side rails of the head section 15 by a bolt 102 extending through apertures in each member and retained by a nut 103, with suitable washers interposed between the several parts. The upper, inner end portion of each of the normally substantially vertical extensions of the leveler tube 101 is chamtered to provide a cam surface 104. -Pivotally mounted on a shouldered bolt 105 extending through a suitable aperture in the vertical wall of the side rails of the head section outwardly from each bolt 105 is a normally inoperative leveler latch 106. These latches normally depend freely from their pivot bolts 105. As shown in FIG. 8, the upper portion of each latch 106 is shaped to provide a cam surface 107 for cooperation with the cam surface 104 on the associated end arm portion of the leveler tube 101. In this FIG. 8, these parts are shown in normal, substantially vertical depending position in full lines. When it is desired to render inoperative the leveler tube 101 to permit downward movement of the head section 15 below normal horizontal position, a latch 106 may be rotated about its pivot 105 from such full line position of FIG. 8 in a clockwise direction to the broken line position therein illustrated. Such movement of the latch 106 engages its cam surface 107 with the associated cam surface 104 on the leveler tube 101 to swing the same to an intermediate inoperative position of approximately 15 from vertical, as shown in broken lines in FIG. 8. Manual release of the actuated latch 106 will result in retention of the parts in such position by the force of gravity exerted upon the leveler tube 101.

Upon subsequent downward movement of the outer end of the head section 15, the leveler tube 101 will be brought into contact with the side rails 22 of the frame 11 and thereafter be swung upwardly relative to the head section. This result in automatic release of the leveler latch 106 which will be returned by gravity to its normally inoperative full line position of FIG. 8. It will be understood that in the exploded Iview of FIG. 7 the leveler tube 101 is shown in such a forwardly disposed inoperative position. Upon subsequent lifting of the outer end of the head section 15, gravity will return the leveler tube 101 to its normal, substantially vertical depending position shown in full lines in FIG. 8. As indicated in FIG. l, a similar leveler tube 101 and associated latches also are mounted in like manner on the knee section 17.

We claim:

1. In an electrically operable bed having a frame supporting means for said frame, an articulated spring mounted on said frame, comprising intermediate, head, knee and foot sections, and actuating means mounted on said frame for effecting desired movements of the spring, comprising hi-low drive means for moving said frame vertically relative to said supporting means, head section drive means for moving said head section relative to said frame, and knee section drive means for moving said knee section relative to said frame; an electric motor mounted on said frame, transmission means mounted on said frame for effecting actuation of said drive means by said motor, function selector means mounted on said frame for selectively determining actuation of said hi-low, head section or knee section drive means, comprising a key rotatable by said rnotor and axially slidable to selectively render any one of said drive means operable by said transmission means, and cushion mounting means interposed between said motor and said frame to facilitate ease of selective axial movements of said key.

2. An electrically operable bed according to claim 1, wherein said cushion mounting means comprises mounting bolts disposed substantially parallel to the axis of rotation of said key.

3. In an electrically operable bed according to claim 1, wherein said spring sections normally are disposed in horizontal position, movement-limiting means interposed between said head and knee sections of said spring and said frame normally operable to prevent downward movement of the outer ends of said head and knee sections relative to said frame below normal horizontal position and selectively movable to permit placing of said spring in Trendelenburg, reverse Trendelenburg and HypereX- tension positions.

4. An electrically operable bed according to claim 3, wherein said movement-limiting means comprises a leveler having normally vertically depending arms pivotally mounted at their upper ends and foot means engageable with said frame, and a normally inoperative, pivotally mounted leveler latch manually swingable to operative position for retaining said leveler arms in a non-vertical position.

5. An electrically operable bed according to claim 4, wherein said latch comprises cam means engageable with a said leveler arm to move the same from normal vertical position as said latch is swung to operative position.

6. An electrically operable bed according to claim 5, wherein downward swinging of said head or knee section relative to said frame with the associated said latch in operative position will cause engagement of the associated said leveler with said frame to release said latch for automatic return to normal inoperative position.

7. An electrically operable bed according to claim 3, wherein said movement-limiting means comprises foot section support means pivotally mounted at the inner end thereof on said frame and pivotally and slidably connected at the outer end thereof with said foot section.

8. An electrically operable bed according to claim 7, wherein said foot section support means comprises a transversely extending pin at the outer end thereof, and a ratchet bracket mounted on said foot section cooperatively receiving said pin.

9. In a bed having a horizontal frame and an articulated spring supported thereby having head, knee and foot sections normally disposed in horizontal position, movement-limiting means interposed between said head and knee sections of said spring and said frame normally operable to prevent downward movement of the outer ends of said head and knee sections relative to said frame below normal horizontal position and selectively movable to permit placing of said spring in Trendelenburg and reverse Trendelenburg positions, comprising levelers pivotally mounted on and normally depending substantially vertically from said head and knee sections in operative position for engagement with said frame, and normally inoperative leveler latches mounted on said head and knee sections and manually movable to operative position to retain the associated said levelers in a non-vertical inoperative position.

10. A bed according to claim 9, wherein said movement-limiting means comprises foot section support means pivotally mounted at the inner end thereof on said frame and pivotally and slidably connected at the outer end thereof with said foot section.

References Cited UNITED STATES PATENTS 2,912,704 11/1959 Burst 5-69X 2,913,300 11/1959 Darnell et al. 5-68 3,237,212 3/ 1966 Hillenbrand et al. 5-68 3,414,913 12/1968 Stanley et al 5*-68 3,429,533 2/1969 Harkness 24S-22X 3,455,525 7/ 1969 Waerno 24S-22X CASMIR A. NUNBERG, Primary Examiner U.S. Cl. X.R. 5-63 '(gjggo UNlTED STATES PATENT oFFIcE CERTIFICATE OF CGRRECTION Patent No. 3,581,319 Dated June l, 1971 Invented@ John F. Stanley and Barron J. Gulliver It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. l, line 59, after "bed" insert is Col. 3, line 24, "level" should be lever Col. 3, line 52, "betwen" should be between Col. 4, line 44, "and" should be are Col. 5, line 45, "downwardy" should be downwardly Claim l, line l (col. 7, line 43), insert a comma after "frame" Signed and sealed this 23rd day of November' 1971.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Acting Commissioner` of Patents

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