Patent Publication Number: US-6339855-B1

Title: Crib or bed with fully accessible patient surface and side rail positioning mechanism therefor

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates generally to cribs or beds having side rails that can be raised and lowered. In particular, the invention relates to a crib or bed that allows full and unimpeded access to a patient on a bed surface when the side rails are in the lowermost position, and it relates to a positioning mechanism for positioning the side rails of the bed or crib. 
     Cribs and beds for infants or small children, which have side rails to prevent the occupant from inadvertently falling to the floor are well known. In addition, cribs or beds with moveable side rails to facilitate placing a child in the crib, removing a child from the crib, or attending to a child that is already in the crib, are also well known. 
     Conventionally, cribs or beds having side rails that are moveable between upper and lower positions are known to include support means to guide the moveable side rails between the upper and lower positions. One example of this type of crib has a fixed board or side rail at the head end of the crib, and a fixed board or side rail at the foot end of the crib. The fixed side rails at the ends of the crib serve as supports and guides for the moveable side rails at either side of the crib. 
     Another example of a type of conventional crib which includes side rails capable of moving between an upper position and a lower position is shown in FIG.  9 . Instead of a fixed side rail to serve as a support and guide, this type of crib utilizes several fixed side rail support beams  100  to support and guide the moveable side rails  103  as they move between upper and lower positions relative to a bed surface  102 . Each of the support beams  100  may have a track or groove in each of its sides in which the moveable side rails  103  can slide. 
     One major disadvantage of the conventional cribs described above is that these cribs severely limit accessibility to the child. Although the crib shown in FIG. 9 may provide more access to a child than a crib having fixed side rails or boards at the ends of the crib, the side rail support beams  100  still limit access to the child by providing an impediment to someone attending to the child. This limited access is magnified in an emergency situation when attending physicians and nurses must have instantaneous access to the child from all areas surrounding the crib, and must be able to move around the crib quickly and easily while still attending to the child. In that emergency situation, the side rail support beams  100  create impediments which cause attending physicians and nurses to waste precious moments navigating around the impediments. In addition, in that emergency situation, an attending physician or nurse should be able to raise or lower one of the side rails and place the side rail into a proper position with a single hand so that their other hand is free to perform other tasks. 
     Accordingly, there is a need for an improved bed or crib: which provides safety and restraint for a child in the crib; which has side rails capable of being easily moved between uppermost and lowermost positions; which includes safety features to prevent the accidental lowering of the side rails; and which provides full and unimpeded access to a child on a bed surface of the crib. In addition, there is a need for an improved positioning mechanism which enables a side rail of a crib or bed to be quickly and accurately positioned with one hand, and which does not create an impediment preventing access to a child on the bed surface of the crib. 
     SUMMARY OF THE INVENTION 
     One object of thee present invention is to provide a crib apparatus which fulfills all of the needs discussed above. The crib apparatus of the present invention comprises a frame, a bed surface supported by the frame, and at least one side rail for enclosing the bed surface and which is connected to the frame along the periphery of the bed surface so that it is moveable. A side rail positioning mechanism is provided at each of the side rails for positioning that side rail. Each of the positioning mechanisms allows its respective side rail to be positioned in an uppermost position so that the top portion of the side rail is above (with respect to a vertical direction) the bed surface. Each of the positioning mechanisms also allows its side rail to be positioned in a lowermost position so that the top portion of the side rail is substantially at or below the bed surface. When the side rails are in the lowermost position, a geometric plane that includes the bed surface is free of impediments thereby allowing unimpeded access to a patient on the bed surface by an attendant. 
     It is to be understood that some portions of the apparatus, such as handles or frame members, may extend slightly higher than a plane in which the bed surface lies when the side rails are in the lowermost position and still provide unimpeded access to a patient. In addition, the top portions of the side rails may extend slightly higher than the bed surface and still be substantially at the bed surface. For example, when the side rails are in the lowermost position, the top portions may extend above the bed surface a distance equal to or less than the front-to-back thickness of a typical child so as to be substantially at the bed surface without impeding access to the child. 
     The present invention may include a plural number of side rails which together enclose the bed surface. In that case, the positioning mechanism for each side rail can position that respective side rail independent of the position of any of the other side rails. Consequently, one side and one end may be in the lowermost position while the remaining side and the remaining end may be in the uppermost position. Alternatively, the present invention can comprise a single side rail that encloses the bed surface and is moveable between an uppermost position and a lowermost position. 
     Each of the side rails may be connected to the frame by bearing blocks. Therefore, each of the side rails is capable of sliding in the bearing blocks between the uppermost position and the lowermost position. In addition, each of the positioning mechanisms can be used to position its side rail in at least one intermediate position between the uppermost position and the lowermost position. 
     In addition to providing a crib apparatus that allows full and unimpeded access to a patient on the bed surface, another object of the invention is to provide a positioning mechanism capable of allowing the side rails of a crib to be moved and positioned without using structural supports or guides that extend above the bed surface. The positioning mechanism of the present invention comprises a handle component mounted to a side rail, and a vertical lock spindle which is rotatably attached to the same side rail and has several lock pins spaced vertically along its length. The positioning mechanism also includes a locking component for receiving the vertical lock spindle, and which is fixed to the frame. The handle component is connected to the lock spindle so that when actuated, the handle rotates the lock spindle enabling one of the lock pins to be released from the locking component. 
     It is important that the positioning mechanism for the side rail of a crib have a safety feature that prevents the accidental lowering of the side rail. The positioning mechanism of the present invention has this type of safety feature. The locking component includes a through-hole for receiving the lock spindle, and includes a pair of vertical grooves extending along the length of the through-hole (in a longitudinal direction of the through-hole). A catch is pivotally mounted within one of the grooves halfway through the length of the through-hole (at a longitudinal midpoint of the through-hole). The side rail can be positioned by being raised so that one of the lock pins passes through the locking component as the catch pivots upwards, and then slightly lowered so that the lock pin comes to rest on the catch within the groove since the catch cannot pivot downward from its normal, or resting, position. In order to lower the side rails, the handle component must be actuated to rotate the lock spindle and the lock pin so that the lock pin can be aligned with the other groove (the groove without the catch). In addition, the side rail must be slightly raised in order to lift the lock pin off of the catch and out of the groove. These two actions—actuating the handle component and lifting the side rail—are necessary to lower the side rail, and comprise the safety feature of the present invention which prevents the accidental lowering of the side rail. 
     As can be seen from the brief summary provided above, the present invention provides an improved crib apparatus which allows full and unimpeded access to a patient on the bed surface, while also providing a safety feature to prevent the accidental lowering of the side rails. In addition, the positioning mechanism for the crib apparatus of the present invention allows one handed raising and lowering of the side rail, which is very important if an attending physician or nurse must quickly raise or lower the side rail while accomplishing at least one other task simultaneously. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects and advantages of the present invention will be apparent from the following description, provided with reference to the following drawings, in which: 
     FIG. 1A is a side view of a crib apparatus according to the present invention in which the side rails are in uppermost positions; 
     FIG. 1B is a side view of the crib apparatus according to the present invention in which the side rails are in lowermost positions; 
     FIG. 1C is a perspective view providing another example of the crib apparatus shown in FIGS. 1A and 1B, and shows the side rails in uppermost positions; 
     FIG. 1D is a perspective view of the crib apparatus of FIG. 1C, in which the side rails are in lowermost positions; 
     FIG. 2A is a side view of the crib apparatus according to the present invention showing the side rails at the ends of the bed surface in uppermost positions and the side rails at the sides of the bed surface in intermediate positions between the uppermost and the lowermost positions; 
     FIG. 2B is a side view similar to FIG. 2A showing the side rails at the ends of the bed surface in uppermost positions and the side rails at the sides of the bed surface in lowermost positions; 
     FIG. 3 is a detailed view of a side rail according to the present invention showing a positioning mechanism; 
     FIG. 4 is a top plan view of a section of a handle component of the present invention; 
     FIG. 5 is a top plan view of a locking component of the present invention, without a catch; 
     FIG. 6A is a side view of the locking component, showing a catch in an open position; 
     FIG. 6B is a side view similar to FIG. 6A, but showing the catch in a closed, or normal, position; 
     FIG. 7A is a perspective view of a portion of the positioning mechanism of the present invention, showing the positioning mechanism in a normal state; 
     FIG. 7B is a perspective view similar to FIG. 7A, but showing the positioning mechanism in an actuated state; 
     FIG. 8A is a side view of a portion of the positioning mechanism in the normal state with the handle removed; 
     FIG. 8B is a side view similar to FIG. 8A, but showing the positioning mechanism in the actuated state; and 
     FIG. 9 is a perspective view showing a conventional crib apparatus. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A crib apparatus according to the present invention is shown in FIGS. 1A-2B. FIG. 1A shows a crib apparatus  1  of the present invention having side rails  3  enclosing a bed surface  2 , and this figure shows the side rails  3  in the uppermost position. It is to be noted that the crib apparatus of FIGS. 1A and 1B may also have a single continuous side rail that encloses a bed surface. However, the following description will be made with reference to the crib apparatus having a plural number of discrete side rails which together enclose a bed surface. This is done for purposes of simplicity, and the details and operation provided are also applicable to a crib apparatus having a single side rail. 
     In the crib apparatus  1  shown in FIG. 1A, each of the side rails  3  is moveably connected to a frame  4 , which supports the bed surface  2 . The frame  4  includes components such as wheels  26 , leg supports  27 , and a bed support  28 . Each of the side rails  3  has multiple spindles  15 , and at least one of the spindles slides through a bearing block  7  which connects each of the side rails  3  to the frame  4 . The bearing blocks  7  enable each of the side rails  3  to slide between an uppermost and a lowermost position. A positioning mechanism  6  is provided at each of the side rails  3  to allow its respective side rail to be positioned in a desired position. 
     The crib apparatus  1  with all of the side rails  3  in the lowermost position is shown in FIG.  1 B. When in the lowermost position, a top portion  5  of each of the respective side rails  3  is substantially at or below the bed surface  2 . In other words, the top portion  5  of each of the side rails  3  does not extend substantially higher than the bed surface  2 , so that the plane in which the bed surface lies is free of impediments. The term “free of impediments” as used herein means that the plane in which the bed surface lies may include some portions of the crib, provided that no portion extends a great enough distance above the bed surface so as to impede access to a child lying on the bed surface by an attendant. Similarly, the term “substantially at” as used herein means that the top portion of each of the side rails does not extend above the bed surface so as to impede access to a child lying on the bed surface. In other words, when all of the side rails are in the lowermost position, no portion of the crib (including the top portions of the side rails) extends above the bed surface more than a distance approximately equal to the front-to-back thickness of a typical child (or other patient). This is exemplified in FIGS. 1C and 1D. FIG. 1C provides an example of the crib apparatus of the present invention, in which the side rails are in the uppermost position, while FIG. 1D shows the same crib apparatus in which the side rails are in the lowermost position. However, the top portions of the side rails in FIG. 1D are substantially at the bed surface because they do not extend above the bed surface more than a distance approximately equal to the front-to-back thickness of a typical child (or patient). Consequently, an attending physician or nurse has unimpeded and full access to a child on the bed surface  2 . 
     FIG. 2A shows the crib apparatus  1  of the present invention in which the side rails  3  along the sides of the bed surface  2  are in an intermediate position. The positioning mechanism  6  for each of the side rails  3  is capable of positioning its respective side rail  3  in at least one intermediate position (i.e., a position between the uppermost position and the lowermost position). FIG. 2B shows the crib apparatus  1  of the present invention in which the side rails  3  along the sides of the bed surface  2  are in lowermost positions, and the side rails  3  along the end of the bed surface  2  are in uppermost positions. The positioning mechanism  6  for each of the side rails  3  does not need to be linked to any of the other side rails or positioning mechanisms. Thus, each positioning mechanism allows its respective side rail to be positioned independent of the position of any of the other side rails. 
     A detailed view of the positioning mechanism  6  for each of the side rails is provided in FIG.  3 . As shown in this figure, each of the positioning mechanisms  6  comprises a handle component  8 , a lock spindle  9  having a plural number of lock pins  10  rigidly fixed to it, and a locking component  11 . The lock pins  10  are vertically spaced along the length of lock spindle  9 , and extend therefrom in a radial direction. The handle component  8  is mounted to one of the side rails  3  at the top portion  5 , and lock spindle  9  is rotatably connected to one of the side rails. The top portion and bottom portion of each side rail each include a plastic bushing, and cylindrical portions at the top and bottom ends of each lock spindle  9  are fitted within those bushings, respectively, so that the lock spindle  9  is able to rotate about its longitudinal axis within those bushings. The lock spindle  9  is slidably received within the locking component  11  so as to be able to slide through and rotate within the locking component  11 . The locking component  11  is rigidly fixed to the frame  4  by a set of screws. 
     FIG. 4 provides a detailed top plan view of a section of the handle component  8 . As shown in this view, a handle grip  16  extends radially from a handle boss  17 , which forms a portion of handle axle  20 . The handle component  8  is mounted to and supported by top portion  5  by handle axle  20 , which extends through a pair of openings in top portion  5  so as to be able to rotate therein. Handle axle  20  includes a concentric flange  14  which is connected to a lock spindle cap  18  by a handle link  19 . Handle link  19  includes a spindle rod  19 C at a first end, and an axle rod  19 A at a second end. The spindle rod  19 C and axle rod  19 A are connected by handle link spring  19 B. Axle rod  19 A is pinned to an outer portion of flange  14  by connector  22  so as to be able to pivot about an axis of connector  22 , and connector  22  pivots relative to flange  14 . The handle axle  20  is also connected to an inner surface of the side rail top portion  5  by a return spring  21 . Both the handle spring  19 B and the return spring  21  are in tension. 
     The locking component  11  is positioned below the handle component  8  and, therefore, is partially obscured in FIG.  4 . However, FIG. 5 provides a top plan view of locking component  11 . As shown in this figure, locking component  11  has a mounting arm  30 , which includes several screw holes  29 . The locking component  11  is fixed to frame  4  by screws which connect mounting arm  30  to frame  4 . A through-hole  13  extends the entire length (or, as viewed from the side, the height) of locking component  11 . A pair of grooves, including catch groove  23  and clearance groove  24 , extend the length of the locking component  11  along the through-hole  13 . In operation, lock spindle  9  slides through the through-hole  13  in locking component  11  while one of the lock pins  10  slides through either the catch groove  23  (when sliding in the upward direction) or the clearance groove  24  (when sliding in the downward direction). This operation will be explained in greater detail below with respect to FIGS. 6A through 8B. 
     FIGS. 6A and 6B show catch groove  23  in the locking component  11 , which has a catch  12  pivotally mounted therein by pivot pin  31 . As explained above, locking component  11  is fixed to frame  4 , while the lock spindle  9  having lock pins  10  fixed thereon is connected to one of the moveable side rails  3 . As shown in FIG. 6A, as the side rail  3  (and, thus, lock spindle  9 ) is raised, the catch  12  is pushed up and caused to pivot about pivot pin  31  into an open position as the lock pin  10  slides through the catch groove  23  in the upward direction. Referring now to FIG. 6B, as the lock pin  10  clears the catch  12 , the catch  12  is returned to its normal position by, for example, gravity. The lock pin  10  is then slightly lowered and comes to rest on the catch  12  because the catch  12  cannot pivot downward past its normal position (shown in FIG. 6B) due to stopping surface  25  which contacts a surface of locking component  11 . Consequently, each of the side rails  3  can be raised and positioned at several intermediate positions, corresponding to the number of lock pins  10  spaced along lock spindle  9  as shown in FIG.  3 . 
     The operation of the handle component  8  will now be explained with reference to FIGS. 7A-8B. FIG. 7A shows the handle component  8 , including handle grip  16 , in a normal state. In the normal state, the lock pin  10  on the lock spindle  9  is aligned with the catch groove  23 . Therefore, when in the normal state, the side rail  3  can be raised into one of the positions as explained above with reference to FIGS. 6A and 6B. However, to lower each of the side rails  3 , the lock pin  10  must be rotated over to the clearance groove  24  in the locking component  11 . The clearance groove  24  does not have a catch  12  mounted inside, so the pin  10  is able to slide downward through clearance groove  24  without obstruction. 
     In order to rotate lock pin  10  so as to align it with clearance groove  24 , the handle grip  16  of the handle component  8  must be rotated clockwise to the actuation state as shown in FIG.  7 B. FIGS. 8A and 8B correspond to FIGS. 7A and 7B, respectively, but clearly show the position of handle link  19  and handle link connector  22  because the handle boss  17  and handle grip  16  have been removed in these views for purposes of clarity. Handle link connector  22  pins axle rod  19 A of handle link  19  to flange  14 , as explained with reference to FIG.  4 . As the handle is rotated clockwise from the normal state shown in FIG. 8A to the actuation state shown in FIG. 8B, handle link connector  22  pulls the handle link  19 . As explained with respect to FIG.  4  and also shown in FIGS. 7A and 7B, spindle rod  19   c  is connected to an outer portion of lock spindle cap  18  by being inserted into a hole in lock spindle cap  18  (and retained by, for example, a cotter pin). Lock spindle cap  18  forms the upper portion of lock spindle  9 . Consequently, when handle link  19  is pulled, it causes lock spindle  9  to rotate about its longitudinal axis, thereby rotating lock pin  10  so that it can align with clearance groove  24 . When the lock pin  10  is aligned with clearance groove  24 , the side rail  3  can be lowered since the lock pin  10  can easily slide downward through clearance groove  24 . Once the lock pin  10  passes through the clearance groove  24  in the locking component  11 , return spring  21  will cause the handle to return to the normal state shown in FIGS. 7A and 8A unless the handle is held in the actuation state. 
     Referring again to FIGS. 6A and 6B, catch  12  is mounted by pivot pin  31  within catch groove  23  at a midpoint in the length B of the through-hole  13  (i.e., a longitudinal midpoint of the through-hole). Therefore, as shown in FIG. 6B, when the lock pin  10  comes to rest on the catch  12 , the lock pin  10  is sitting within the catch groove  23 . Consequently, the handle component  8  cannot rotate the lock spindle  9  so as to align the lock pin  10  with clearance groove  24  unless the side rail  3  is raised slightly to lift the lock pin  10  out of the catch groove  23 . Thus, two actions—raising the side rail slightly and actuating the handle—are necessary in order to lower the side rails. This is an important feature to prevent the accidental lowering of one of the side rails. 
     With reference to FIGS. 7A through 8B, handle spring  19 B connects axle rod  19 A to spindle rod  19 C so as to form handle link  19 . Handle spring  19 B enables an operator, such as an attending physician or nurse, to complete the two actions necessary for lowering each side rail in any order. That is, the side rail  3  can be raised to lift the lock pin  10  out of catch groove  23  and then the handle grip  16  can be turned to rotate the lock spindle  9  and align the lock pin  10  with the clearance groove  24 , or the handle grip  16  can first be turned while pin  10  is still in catch groove  23  (thus stretching handle spring  19 B), and then the side rail can be raised slightly to lift the lock pin  10  out of catch groove  23 . It should be noted that if the handle is actuated before raising the side rail, the lock pin  10  will immediately be aligned with the clearance groove  24  upon being lifted out of the catch groove  23  due to the force of tensioned handle spring  19 B. As can be seen from this description, the positioning mechanism of the present invention can be actuated with one hand and, therefore, an attending physician or nurse has the other hand free to complete other necessary actions. 
     The crib apparatus of the present invention has been described for the purpose of illustrating a particular embodiment. However, it is recognized that various changes, modifications, and additions may be made to the illustrated embodiment without departing from the spirit and scope of the present invention.