Abstract:
An articulating bed incorporating a frame having side frame members and a rigid cross frame member extending between the side frame members employs a flexible support member secured to the rigid cross frame member. Support arms engage an upper body portion of the flexible support member with lubricious support and are rotatable through a range of motion from an aligned position with the side frame members to a fully elevated position angularly supporting the upper body portion in a raised position. A leg portion adjustment member engages the flexible support member at a knee position intermediate a thigh portion and a leg portion of the flexible support member. The leg portion adjustment member is rotatable through a range of motion from an aligned position with the side frame members to a fully elevated position placing the knee position at an elevated location with angular positioning of the thigh portion and leg portion.

Description:
REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority of U.S. Provisional Application Ser. No. 61/673,878 filed on Jul. 20, 2012 entitled ARTICULATING BED WITH FLEXIBLE MATTRESS SUPPORT and having a common assignee with the present application, the disclosure of which is incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Field 
         [0003]    This invention relates generally to the field of adjustable beds and more particularly to a structure for an articulating bed having an integral adjustable lumbar support and head angle adjustment with a flexible mattress support. 
         [0004]    2. Description of the Related Art 
         [0005]    Articulating beds have long been used in hospital and healthcare facilities to allow positioning of a patient in a reclining position, sitting position, elevated leg position or combinations of these positions. General usage of articulating beds has been rapidly expanding due to the comfort and convenience available from adjusting the bed to desired positions for reading, general relaxation or sleeping. 
         [0006]    The mechanical structure and drive mechanisms for such articulating beds must be able to support the weight of both a mattress and the occupant. Due to the size, weight, fabrication materials and configuration of the mattress and supporting structure, maintaining rigidity in the system may also be challenging. Typical articulating beds provide an upper body positioning element and a thigh and lower leg positioning element either individually active or with combined actuation. However, the articulating elements are typically rigid elements that extend in both a lateral and longitudinal dimension. These rigid elements may restrict the shaping of the mattress and create zones in the bed that are not ergonomically ideal. 
         [0007]    One noted disadvantage of articulating bed systems when both the upper body positioning element and the leg positioning elements are elevated is the tendency for positioning of the lower back in a curved posture which may result in undesirable lumbar strain. Lumbar positioning or support elements have been proposed. However, adjustment elements have tended to adversely reposition, strain or damage the mattress. 
         [0008]    Similarly, head angle with most articulated beds with the upper body positioning element in the elevated position is not satisfactory due to the linear alignment of the head and body. Adjustment systems for creating an angled relationship between the upper body portion of the mattress and a portion wherein the head rests have also been available but actuation systems have proved to be complicated or unsightly since the upper body portion articulating element is exposed in the elevated position 
         [0009]    It is therefore desirable to provide an articulating bed having a flexible mattress support member and providing lumbar support adjustment with reduced mattress interference and a head portion adjustment with simple and unimposing actuation elements. 
       SUMMARY 
       [0010]    The embodiments disclosed herein overcome the shortcomings of the prior art by providing an articulating bed incorporating a frame having side frame members and a rigid cross frame member extending between the side frame members which employs a flexible support member secured to the rigid cross frame member. Support arms engage an upper body portion of the flexible support member with lubricious support and are rotatable through a range of motion from an aligned position with the side frame members to a fully elevated position angularly supporting the upper body portion in a raised position. A leg portion adjustment member engages the flexible support member at a knee position intermediate a thigh portion and a leg portion of the flexible support member. The leg portion adjustment member is rotatable through a range of motion from an aligned position with the side frame members to a fully elevated position placing the knee position at an elevated location with angular positioning of the thigh portion and leg portion. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    These and other features and advantages of the present invention will be better understood by reference to the following detailed description of exemplary embodiments when considered in connection with the accompanying drawings wherein: 
           [0012]      FIG. 1  is a side view of the adjustable bed system without side supports and the flexible member flat; 
           [0013]      FIG. 2  is a pictorial view from under the bed; 
           [0014]      FIG. 3  is a top pictorial view of the bed with the flexible member flat showing the securing discs; 
           [0015]      FIG. 4  is side view of the adjustable bed system with the upper body portion raised; 
           [0016]      FIG. 5  is a pictorial view of the bed with the head portion raised; 
           [0017]      FIG. 6  is a side view of the bed with the head portion and leg portion raised; 
           [0018]      FIG. 7  is a pictorial view of the bed with the head and leg portions raised 
           [0019]      FIG. 8  is a side hidden line view of the bed with the head and leg portions raised and a mattress in place; 
           [0020]      FIG. 9  is a pictorial view with the mattress in place; 
           [0021]      FIG. 10  is a side hidden line view of the bed with the head adjustment and lumbar adjustment activated; 
           [0022]      FIG. 11  is a pictorial view with the head adjustment and lumbar adjustment activated; 
           [0023]      FIG. 12  is a pictorial view as in  FIG. 11  with a mattress installed. 
           [0024]      FIG. 13A  is an isometric view of an exemplary components for the cam element; 
           [0025]      FIG. 13B  is an isometric view of the cam element with a rotation lever incorporated; 
           [0026]      FIG. 14A  is an isometric view of an alternative cable actuation system for the cam element; 
           [0027]      FIG. 14B  is an isometric view of the assembled cam element of  FIG. 14A ; 
           [0028]      FIG. 14C  is a side view of the actuator arrangement for the cable actuation system; 
           [0029]      FIG. 15  is an alternative embodiment of the support arm shuttle; 
           [0030]      FIG. 16  is a side view of the shuttles at various positions for constraining the lumbar support shape; and, 
           [0031]      FIG. 17  is a side view of an alternative embodiment for the leg portion adjustment. 
       
    
    
     DETAILED DESCRIPTION 
       [0032]    Embodiments shown in the drawings and described herein provide an actuation system for an articulating bed which eliminates the rigid individual support platforms and uses a continuous flexible support member for the mattress. Referring to the drawings,  FIGS. 1 and 2  show the adjustable bed system  10  which incorporates a flexible support or member  12  to support a mattress (shown in later figures). The flexible support in an exemplary embodiment is a ⅛ inch sheet of fiber reinforced plastic (FRP) which is fire resistant (FR). Side frame members  14  support a cross member  16  to which the flexible member  12  is secured using plates or discs  18  (best seen in  FIG. 3 ) with bolts extending through the FRP. Rotatable upper body support arms  20  support an upper body portion  13  of the flexible support member  12  toward the upper end of the bed. The flexible support member  12  is lubriciously supported on the support arms  20  to reposition itself during motion of the support arms. In one example embodiment, shuttles  22  which are supported on the support arms  20  are attached to the flexible support member  12 . A leg portion adjustment member  24  is positioned to contact the flexible support member at approximately the knee position  25  of a user between a thigh portion  15  and lower leg portion  19  of the flexible support member  12 . The side frames may include insets which receive the edges of the flexible support member  12  in the flat condition. 
         [0033]    As seen in  FIGS. 4 and 5 , the upper body portion  13  of the flexible support member  12  may be raised by rotating the upper body support arms  20  about axles  26  extending to and supported by the side frame members  14 . Actuation levers  21  on the support arms  20  may be attached to an actuator  23  for rotation. The shuttles  22  reciprocate along the support arms  20  to maintain the flexible support member  12  in contact with the support arms at desired points for proper shaping of the mattress including extension of lumbar and neck angle adjustment elements as will be described in greater detail subsequently. 
         [0034]    As shown in  FIGS. 6 and 7 , the leg portion adjustment member  24  may be rotated about axle  28  which raises the flexible support member  12  at the knee position of the user. The flexible support member  12  flexes over the rotated leg portion adjustment member seeking a neutral position with the thigh portion  15  and lower leg portion  19  draped over the leg portion adjustment member  24 . The flexible support member  12  establishes a smooth curvature in both the upper body portion  13  and thigh and lower leg portions  15 ,  19  of the bed based on natural flexing with the center of the member secured at the rigid cross member  16 .  FIGS. 8 and 9  show the bed in the actuated position for both the upper body portion and leg portion with a mattress  30  resting on the flexible support member  12 . In prior art beds, mattresses tend to lift from the support platforms in the articulated position. The flexible support member  12  naturally contours the angles of the articulation to better maintain the positioning of the mattress on the support member. In addition, mattress retainers such as those disclosed in US patent application Ser. No. 13/367,616 entitled Mattress Retainer System for an Adjustable Bed having a common assignee with the present application, the disclosure of which is incorporated herein by reference, may be used to constrain the mattress to the flexible support member  12  at the head and foot. 
         [0035]    Additionally, the flexible nature of the flexible support member  12  allows the addition of specific contouring elements for lumbar support and head angle position. As shown in  FIGS. 10 and 11 , a lumbar positioning element is provided by a first rotatable cam element  32  attached between the upper body support arms  20  is rotated to flex the flexible support member  12  outward in a lumbar portion  33 . As shown in  FIG. 12  the mattress  30  adopts the flexed position providing gently curving additional support in the lumbar region of the users back. Similarly, a neck angle adjustment element is provided by a second rotatable cam element  34  attached between the upper body support arms  20  rotatable to flex the flexible support member  12  outward in a head portion  35  to provide additional angled support for the users head. 
         [0036]    The cam elements  32 ,  34  may be formed from multiple cam segments  36  as shown in  FIG. 13A  which are mounted on a splined shaft  38  to create a cam element of the desired width for the articulating bed. A rotation lever  40  adapted to receive the splined shaft may be interspersed in the cam elements at a desired location for attachment to an actuator as shown in  FIG. 13B . In alternative embodiments, one cam segment may integrate the rotation lever. Rotation of the splined shaft results in concerted rotation of the multiple cam segments. Additionally, while shown in the drawings as extending the entire width of the splined shaft, the cam segments  36  may be positioned over only a portion of the shaft width to tailor the lumbar or neck angle adjustment cam elements to engage a portion or selected portions of the flexible support member  12  and hence the mattress. 
         [0037]    Actuation of the cam elements is accomplished in alternative embodiments through the use of a sheathed cable  50  as shown in  FIGS. 14A-C . The cam segment  36  engages a key  52  on the end of cable  50  in a relief  54 . A lateral slot  56  allows installation of the key into the relief while an adjoining longitudinal slot  58  engages the cable for operation. A securing lug  53  on a sheath or housing  55  for the cable attached to the support arm  20  provides actuation support for the cable. As shown in  FIG. 14B , the cable  50  extends from the cam segment and, upon tensioning of the cable rotates the cam segment and splined shaft  38  which in turn rotates additional cam segments. Relaxation of the tension on the cable allows the cam segments to rotate back to a flush position with the support arms  20  as shown in  FIG. 14A . Engagement of the flexible support member  12  by the cam segments may rely on lubricious surface engagement between the cam segments and the under surface of the flexible support member or wheels  60  may be included on the engagement ends of the cam segments as shown in  FIGS. 14A and 14B . Cables for actuation of both the lumbar positioning first cam element  32  and the head angle positioning second cam element  34  may be routed to actuators mounted remotely from the actual cam elements. Use of the cable for actuation of the cam element allows placement of an actuator  62  within the frame on the side frame member  14  or other hidden location for actuation through tensioning of the cable providing a very clean appearance for the exposed structure of the articulated bed as shown in  FIG. 14C . 
         [0038]    Shaping of the displacement of the flexible support member  12  by the cam elements  32 ,  34  for the lumbar and neck angle support is accomplished by positioning and constraint of the shuttles  22  on the support arms  20 . As shown in  FIG. 15 , the multiple shuttles shown in  FIGS. 1-11  may be replaced by a single shuttle  42  on each support arm intermediate the lumbar cam element  32  and neck angle cam element  34 . Motion of the shuttle  42  is constrained between the lumbar cam element  32  and neck angle adjustment cam element  34  thereby naturally shaping the flexible support member over the cam elements when activated. Constraint of the flexible support member  12  at the shuttle  42  and rigid cross member  16  provides shaping of the flexible support member in response to rotation of the lumbar cam element as shown in  FIG. 15 . 
         [0039]    Alternatively one or both of the shuttles  22   a  and  22   b  may be constrained for motion along the support arms  20  at defined extents to provide specific shaping curvature of the flexible support member  12  in response to adjustment of the lumbar and neck angle cam elements. As an example, as shown in  FIG. 16 , shuttle  22   a  may be unconstrained in a lower initial position  22   a ′ in response to a first retracted position of the lumbar support with shuttle  22   b  unconstrained in an upper position  22   b ′and the flexible support flat as shown by profile  12 ′. Upon rotation of the lumbar support cam element  32  into an extended position, shuttle  22   a  is drawn upward along the support arm  20  to a second position designated by  22   a ″, however, to provide a desired curvature for the lumbar region of the flexible support member as shown by profile  12 ″ and mattress, the shuttle  22   a  may be constrained by a stop  48  in the upper second position. Similarly, shuttle  22   b  is unconstrained in an upper initial position  22   b ′ with the lumbar support retracted and upon rotation of the lumbar cam element  32  is drawn downward along the support arm  20  to a lower second position  22   b ″. A stop  51  may be employed in to define the lower second position  22   b ″. The initial positions of shuttles  22   a  and  22   b  are responsive to the position of the upper body portion of the flexible support member  12  as positioned by the angle of the support arms  20 . The position stops may chosen to provide any desired profile by positioning of the shuttle as shown by an exemplary third lower position  22   a ′″ and  22   b ′″ with flexible support profile  12 ′ 
         [0040]    Similarly, the stop  51  may limit downward travel of shuttle  22   b  in response to activation of the head angle cam element  34 . As shown in  FIG. 16  shuttle  22   b  may reside unconstrained in an upper initial position  22   b ′ with the head angle in alignment with the upper body portion of the flexible support member. Upon rotation of the head angle cam element  34  to raise the head angle, shuttle  22   b  may translate downward to a lower second position  22   b ″ with further downward translation of the shuttle constrained by stop  51 . 
         [0041]    The stops and shuttle positioning may additionally be adjustable for varying the curvature associated with the lumbar positioning element for different mattress thickness and/or stiffness as shown by positions  22   a ′″ and  22   b′″.    
         [0042]    The lack of securing attachment of the flexible support member  12  to the leg portion adjustment member  24  additionally allows adjustment of the positioning of the knee bend in the flexible support member to accommodate the length of the user&#39;s thigh from hip to knee. When the articulating structure of the bed is adjusted for raising the upper body portion  13 , the user naturally settles into a seated position at the curvature induced in the mattress. The length of the thigh then becomes the determining dimension desire for the knee bend location. Since this may vary significantly between tall and short users, conventional beds do not adequately provide for this variation. In the present embodiments, the longitudinal position of the leg portion adjustment member  24  may be adjusted to accommodate this length. Alternatively, a single lever actuation element  66  as shown in  FIG. 17  may be employed to raise the flexible support member  12  at the knee position. Rotating the actuation element by an actuator  68  to a normal raised position  66 ′ places the thigh portion  15  and lower leg portions in the rotated positions draped normally over the knee position. By rotating beyond the vertical to a position  66 ″, a shortening of the knee position relative to the rigid cross member  16  is obtained thereby allowing for shorter length of the thigh portion  15 ″. The natural height reduction created by the overcenter rotation of the actuation element  66  at position  66 ″ further compensates for a shorter thigh length. As shown in  FIG. 17 , the actuation element  66  may employ a wheel  70  for engagement of the underside of the flexible support member  12 . 
         [0043]    Having now described various embodiments of the invention in detail as required by the patent statutes, those skilled in the art will recognize modifications and substitutions to the specific embodiments disclosed herein. Such modifications are within the scope and intent of the present invention as defined in the following claims.