[0001]    This application is one of two continuations of U.S. patent application Ser. No. 12/437,995 which is a continuation of U.S. patent application Ser. No. 12/045,914, now abandoned, which is a continuation of U.S. patent application Ser. No. 11/460,701 filed on Jul. 28, 2006, now U.S. Pat. No. 7,350,248, which is a continuation of U.S. patent application Ser. No. 11/093,253, filed Mar. 29; 2005, now U.S. Pat. No. 7,237,284, which is a continuation of U.S. patent application Ser. No. 10/399,465, filed Apr. 18, 2003, now U.S. Pat. No. 6,874,179, which is a national phase application of PCT/FR01/03224, filed Oct. 18, 2001, which claims priority to French Application Serial No. FR 00 013366, filed Oct. 19, 2000, the disclosures of all of which are expressly incorporated herein by reference. 
     
    
     BACKGROUND AND SUMMARY OF THE INVENTION 
       [0002]    The present invention relates to a bed, in particular a hospital bed, which is fitted along at least one of its two longitudinal sides with a plurality of adjacent individual barrier elements, each extending over a fraction of the length of the bed. 
         [0003]    The term “hospital bed” is used to mean any bed fitted with optionally power driven means that enable assistance to be given to a person lying in the bed. 
         [0004]    At present, nearly all such beds are fitted with at least one retractable longitudinal barrier having the function of preventing the patient from falling out of bed while unattended. 
         [0005]    Such barriers have the characteristic of extending along the entire length of the bed in the raised position and in the lowered position, such that they are of no help to a person seeking to move from a prone position to a sitting position. Such a person often seeks a support point for making the movement easier. That type of barrier, which can be referred to as “full”, provides no help under such circumstances. 
         [0006]    Another drawback of such barriers is psychological in nature, based on the fact that they give the bed a “cage” appearance which is no help in making a patient feel at ease. 
         [0007]    Those problems have been solved in part by proposing to fit beds with barriers that are independent of one another, each extending over a fraction of the length of the bed. In order to distinguish such barriers from full barriers, they are referred to below as barrier “elements”. 
         [0008]    Thus, two distinct barrier elements extend along either side of the bed, with the gap between them being large enough to allow the patient to take up a sitting position. An example of that state of the art is shown in document U.S. Pat. No. 5,216,768. 
         [0009]    Each element may be secured to the bed plane that receives the mattress, even when the bed plane comprises a plurality of portions, at least one of which can be moved into a position other than horizontal. 
         [0010]    When the patient is in the prone position and the elements are in the raised position, the elements prevent the patient from falling out of bed unless the patient manages to position the torso between the two elements. 
         [0011]    Safety regulations require the spacing between the elements to be less than 60 millimeters (mm) or greater than 235 mm, whatever their relative position. This means, for example, that when an element is secured to a portion of the bed plane, said portion being in a raised position, then the spacing between said elements and the second element must still comply with the values specified above. 
         [0012]    In spite of that, there remains some risk of accident, particularly when a patient in a sitting position between the elements falls. The patient&#39;s torso can then become wedged between the elements. 
         [0013]    In addition, each of the two barrier elements requires its own mechanism for fixing to the bed, together with a mechanism for retracting it beneath the bed plane. It will readily be understood that this increase in mechanical parts increases the cost price of the bed and makes the structure and the operation of the bed more complicated. 
         [0014]    An object of the present invention is to mitigate those drawbacks. 
         [0015]    More precisely, a particular object is to provide a bed having individual barrier elements, the bed presenting the advantages associated with such elements and also with traditional full barriers, without presenting the drawbacks. 
         [0016]    In other words, the object of the invention is to provide a bed whose barrier system can be used equally well as an individual barrier element and as a full barrier. 
         [0017]    The invention seeks to provide a bed which can be used without risk of accident, and in particular without risk of the fingers or the limbs becoming pinched or trapped between moving parts. 
         [0018]    In conventional manner, this bed, in particular a hospital bed, is fitted with a plurality of adjacent individual barrier elements along at least one of its longitudinal sides, the barrier elements extending vertically and each occupying a fraction of the length of the bed. 
         [0019]    According to an illustrative embodiment of the present disclosure, a patient support includes a base structure including a longitudinal side, a first barrier element including a first portion, and a second barrier element including a second portion. The first and second barrier elements are positioned along the longitudinal side of the base structure. The barriers are adapted to move between raised and lowered positions. Each of the first and second barrier elements occupies a fraction of the length of the patient support. The barriers are positioned such that the first portion and the second portion overlap when both the first barrier element and second barrier element are in the raised position. 
         [0020]    According to another illustrative embodiment of the present disclosure, a patient support includes a frame, a deck, a head end barrier element, and a foot end barrier element. The frame includes a head end, a foot end, and longitudinal sides. The deck is coupled to the frame and includes at least a head section and a seat section. The head end barrier element is positioned along at least one of the longitudinal sides of the frame near the head end. The head end barrier includes a first portion. The foot end barrier element is positioned along at least one of the longitudinal sides near the foot end. The foot end barrier element includes a second portion. The first portion and the second portion overlap allowing the foot end barrier element and the head end barrier element to extend substantially the entire length of the patient support. 
         [0021]    According to yet another illustrative embodiment of the present disclosure, a patient support includes a frame, an articulating deck, a first siderail, and a second siderail. The frame includes a head end, a foot end, and longitudinal sides. The articulating deck is supported by the frame. The deck includes a head section and a foot section. The head section is moveable relative to the foot section. The first siderail is positioned along one of the longitudinal sides. The second siderail is positioned adjacent the first siderail. The second siderail includes a first portion positioned between the first siderail and the second siderail where the first siderail overlaps the second siderail. At least one of the first and second siderails moves with the head section during articulation of the deck. 
         [0022]    Additional features and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of illustrated embodiments exemplifying the best mode of carrying out the invention as presently perceived. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0023]      FIG. 1  is a simplified perspective view of a hospital bed in accordance with the invention, the two barrier elements being in the overlapping position, one on another and folded up above the plane of the bed; 
           [0024]      FIG. 2  is substantially analogous to  FIG. 1 , the two elements being retraced beneath the plane of the bed; 
           [0025]      FIG. 3  shows the same bed, with one of the elements being shown both in dashed lines in a half-way tilted position and in continuous lines in a fully tilted position; 
           [0026]      FIGS. 4 and 5  are perspective views of the bed in which the moving bed plane has been positioned so as to cause the mattress to take up a seat position; in these figures, the barrier elements are shown respectively in the overlapping position and in the deployed position; 
           [0027]      FIG. 6  is a longitudinal side view of the top portion of the bed of  FIGS. 1 to 5 , i.e. of the portion which includes the bed plane and all of the pieces of equipment situated above it; 
           [0028]      FIG. 7  is a perspective view of two elements in the overlapping position, showing more particularly their face facing towards the inside of the bed and the means for fixing them to the bed plane; 
           [0029]      FIGS. 8 and 9  are fragmentary plan views in section on a longitudinal plane showing the barrier elements and a first embodiment of a hinge mechanism uniting them; 
           [0030]      FIG. 10  is a simplified front view of another hinge mechanism; 
           [0031]      FIG. 11  is a view of the  FIG. 10  mechanism in section on the plane XI-XI; 
           [0032]      FIG. 12  is an exploded perspective view of the parts making up the hinge mechanism of  FIGS. 10 to 11 ; 
           [0033]      FIG. 13  is a side view of the parts making up another hinge mechanism; 
           [0034]      FIG. 14  is a front view of the  FIG. 13  mechanism; 
           [0035]      FIGS. 15 and 16  are section views of the mechanism in the preceding figures on section planes XV, XV and XVI, XVI in  FIGS. 13 and 14 ; 
           [0036]      FIG. 17  is an exploded perspective view of the parts forming the mechanism; 
           [0037]      FIGS. 18 ,  19 , and  20  are views of another embodiment of the hinge means, respectively a front view and sections on planes XIX, XIX and XX, XX of  FIG. 18 ; 
           [0038]      FIGS. 21 ,  22 , and  23  are perspective views and a front view of the three parts making up this embodiment of a hinge; 
           [0039]      FIGS. 24 and 26  are general views of means enabling the barrier elements to be locked and unlocked when they overlap each other, respectively in the folded-up position and in the retracted position beneath the plane of the bed; 
           [0040]      FIGS. 25 and 27  are detail views of said means; 
           [0041]      FIGS. 28 and 29  are fragmentary front views of barrier elements in the deployed position and in the overlapping position, showing more particularly means for actuating the locking and unlocking means; 
           [0042]      FIGS. 30 and 31  are fragmentary views, respectively a front view and a cross-section view of means for guiding the pivoting barrier element as it moves along the bed; 
           [0043]      FIGS. 32 and 33  are fragmentary views respectively a front view and a perspective view of one of the barrier elements and of additional means enabling it to co-operate in sliding with a rail provided on the plane of the bed; 
           [0044]      FIG. 34  is a simplified longitudinal side view of the top portion of an additional embodiment having three barrier elements, one of which is slidable; 
           [0045]      FIG. 35  is a view analogous to that of  FIG. 34 , with the “bed head” portion being raised, while the “bed foot” portion is lowered; 
           [0046]      FIG. 36  is a perspective view of an additional embodiment of a retractable support part for one of the pivoting barrier elements, said part being shown in its raised position; 
           [0047]      FIG. 37  is a view of the same part, seen in another direction; and 
           [0048]      FIG. 38  is also a view of the same part, but in the retracted position. 
       
    
    
     DETAILED DESCRIPTION 
       [0049]    The bed shown in accompanying  FIGS. 1 to 5  has the general appearance of a hospital bed of well-known type. 
         [0050]    It is constituted by a base structure  1  made up of a solid metal frame  10  having castors  11  attached thereto and defining between them an elongate rectangular shape. 
         [0051]    The frame supports equipment  12  for raising and lowering the bed proper, mainly for the purpose of making it easier for hospital staff to take action. Such equipment is also provided for positioning the patient in so-called “safe” positions, in particular acclivous and declivous positions (sloping up and sloping down). 
         [0052]    Naturally, the base structure can receive other mechanical and/or electronic equipment suitable for co-operating with the bed proper. 
         [0053]    This base structure also has fixed thereto vertical panels at the head and foot ends of the bed, given respective references  4  and  4 ′ in the figures. They extend transversely, defining the longitudinal ends of the bed. 
         [0054]    As can be seen, these panels present large cutouts  40  and  40 ′ which form handles and make it easier to maneuver the bed when it is desired to move it within a room or outside the room. 
         [0055]    In conventional manner, the bed proper is essentially formed by that which is referred to throughout the present application as the “bed plane”, i.e. a surface that coincides with or is situated immediately below the bottom face of the mattress and that is usually constituted by a hard plane made up of several portions, with at least one of these portions being movable so as to occupy positions other than horizontal. 
         [0056]    This makes it possible, in particular by tilting up one or another of these portions, to put the mattress in a position similar to that of a seat. 
         [0057]    This bed plane is not visible in  FIGS. 1 to 5 . These figures show only the mattress  3  which rests thereon. 
         [0058]    As shown in  FIGS. 1 to 3 , the bed is fitted in accordance with the invention with two barrier elements  5  and  5 ′ that are hinged relative to each other. They extend parallel to one of the longitudinal edges of the bed. 
         [0059]    These barrier elements are in the form of generally rectangular plates. Their dimensions are substantially similar, such that when they are superposed one on the other ( FIGS. 1 and 2 ) in an “overlapping” position, they occupy much the same space as a single element. 
         [0060]    In the longitudinal direction, they are of a size that is no greater than half the length of the mattress. In this way, when they are deployed, they occupy practically the entire length of the mattress. 
         [0061]    In a variant embodiment, the first element could occupy substantially three-fourths of the length of the bed while the second element occupies the last fourth. 
         [0062]    In yet another embodiment, there could be three such elements, each occupying no more than one-third of the length of the bed. 
         [0063]      FIGS. 6 and 7  show a slightly different embodiment of these two elements. 
         [0064]    In an additional embodiment (not shown), these elements may have large open areas or glazed areas, like traditional barriers. 
         [0065]      FIG. 6  is a side view of the bed plane  2  on which there rests the mattress  3  of the bed. This bed plane is built up by assembling bars. In the example shown, it comprises two portions  20  and  21  which are hinged relative to each other about a horizontal axis Y, Y′ which is generally perpendicular to the longitudinal direction of the bed. 
         [0066]    The portion  20  is at the foot end of the bed while the portion  21  is at its head end. When the portion  21  occupies a raised position, this enables the mattress to be put into a position similar to that of a seat. 
         [0067]    With reference to  FIG. 7 , there can be seen an assembly  210  of bars constituting a fraction of the portion  21  of the bed plane. 
         [0068]    On one of the longitudinal sides of the portion  210  there is fixed a piece of equipment  50 ′ enabling the barrier elements  5  and  5 ′ to be positioned either in a vertical raised position above the bed plane ( FIGS. 1 ,  3 ,  6 , and  7 ), or else in a vertical position retracted below the bed plane ( FIG. 2 ). 
         [0069]    This is a deformable parallelogram mechanism. It is not described in greater detail herein since, properly speaking, it does not form part of the invention. 
         [0070]    Nevertheless, reference can be made to French patent No. 91/11185 in the name of the present Applicant which describes in particular the operation of the linkage constituting the mechanism  50 ′. 
         [0071]    The mechanism makes it easy to move the barrier elements from the folded-up position of  FIG. 1  to the retracted position of  FIG. 2 . 
         [0072]    In  FIG. 2 , arrow h represents the upward movement of the barrier elements. The retracted position beneath the bed plane is particularly useful when hospital staff need to gain access to the bed without their own movements being impeded. 
         [0073]    Naturally, the piece of equipment  50 ′ could be replaced by some other mechanical system suitable for performing the function of retracting the elements in the overlapping position. 
         [0074]    In accordance with the invention, the barrier elements  5  and  5 ′ are hinged relative to each other about an axis XX′ which is generally perpendicular to the longitudinal axis of the bed. This hinge is constituted by a mechanism that is not visible in  FIG. 6  and comprising, for example, a cylindrical spacer, distance pieces, and a helical spring. 
         [0075]    Nevertheless, any other known type of hinge mechanism may be adopted. 
         [0076]    Certain embodiments of this mechanism are described below. The mechanism may merely comprise a mechanism enabling the elements to turn relative to each other without allowing them to be separated. Nevertheless, this option for separating the elements, or at least for spacing them apart from each other, is preferred so as to give access for cleaning the barrier elements in full, in particular in their zones that face each other, and still more particularly, in the zone where they overlie each other. 
         [0077]    With reference to  FIGS. 8 and 9 , there follows a description of a first embodiment of the hinge mechanism for the barrier elements. 
         [0078]    Each of the elements  5  and  5 ′ presents a circular opening of the same diameter passing through its thickness, this opening receiving a bushing  60 . The bushing comprises a generally cylindrical body with a generally flat peripheral flange  601  at one of its ends. The flange is received in and comes into abutment against a countersink provided in the outside face of the barrier element  5 . The length of the bushing is such that the body  60  is flush with the opposite face of the element  5 ′. 
         [0079]    The axis of the bushing coincides with the hinge axis XX′ between the elements. 
         [0080]    The inside space of the bushing receives a sleeve  61 , and more particularly the body  611  thereof. 
         [0081]    This body is longitudinally hollow and communicates via one of its ends with a generally flat head  610  of circular shape and of diameter greater than that of the body. Between the bushing  60  and the head  610  of the sleeve there is interposed a compressible O-ring  63 , e.g. made of natural rubber. 
         [0082]    At the opposite end of the body there is a generally longitudinal projection  612  extending beyond the thickness of the two elements. 
         [0083]    A pivoting control handle  62  of conventional type having a cam surface  620  is hinged thereto. This hinge is about an axis  613  that is generally parallel to the planes occupied by the elements  5  and  5 ′. 
         [0084]    The sleeve  61  is engaged in the bushing  60  while the handle  62  is in alignment therewith (see  FIG. 9 ). 
         [0085]    By folding the handle down, the sleeve is moved in translation, thereby compressing the O-ring  63  ( FIG. 8 ). 
         [0086]    This configuration makes it possible to secure the elements  5  and  5 ′ to each other while also making it possible for one of them to turn about the axis XX′. 
         [0087]    Nevertheless, the tightness with which the handle  62  is actuated serves to brake turning of the element. 
         [0088]    When it is desired to gain access to the facing faces of the elements  5  and  5 ′, in particular for the purpose of cleaning them, it suffices to fold the handle out so that it is in alignment with the sleeve ( FIG. 9 ) and to separate the element  5  by pulling on it. 
         [0089]    Another embodiment of the hinge mechanism is described below, more particularly with reference to  FIGS. 10 to 12 . 
         [0090]    In the same manner as above, each of the barrier elements presents an opening through its thickness enabling the component parts of the hinge mechanism to be inserted therein. 
         [0091]    In this case, the hinge mechanism comprises a first part referenced  70  and referred to as the inside cap. It is for mounting beside the face of the element  5 ′ that faces towards the inside of the bed. For this purpose, said face is locally recessed in order to receive said cap. 
         [0092]    The cap comprises a circular plate in the form of a disk  700  whose inside face presents projecting studs  701  at the corners of a square. They are intended to receive means for fastening to the barrier elements, in particular screw fastener means. 
         [0093]    On the same side of the plate  700  there extends from its center a generally cylindrical sleeve  702 . The length of the sleeve is such that when the cap is in place on the element  5 ′, it extends into the element  5 . 
         [0094]    This sleeve presents a set of axial slots  704  that are equidistant angularly. Between them, pairs of slots define branches  703 . The cap is preferably made of a slightly deformable plastics material, such that the branches  703  are radially deformable. Their free ends form respective catches  705  with chamfered faces looking outwards. 
         [0095]    The mechanism also comprises a spacer  71  suitable for being received in a recess provided for this purpose in the element  5 . It comprises a generally cylindrical body and a plane peripheral flange  710  projecting outwards. This flange presents a series of orifices  711  for fastening the spacer to the outside face of the element  5 . The body of the spacer has a first axial portion  712  which extends from the flange  710 . 
         [0096]    It communicates with another cylindrical portion of smaller diameter  714  via a shoulder-forming transition zone  713  extending parallel to the flange  710 . The inside diameter of the portion  714  is equal to the outside diameter of the sleeve  702 , ignoring clearance. 
         [0097]    The central opening of the spacer  7  receives a circular button  72  having a hollow inside and which includes in particular an axially-extending partition  720  whose function is explained below. 
         [0098]    Finally, the mechanism includes an outside cap  73  essentially constituted by a flat disk  730  with a central recess  731  for passing the button  72 . 
         [0099]    The inside cap  72  and the spacer  71  are engaged in each other from opposite sides of the elements  5  and  5 ′. In so doing, the portion  714  of the spacer encounters the catches  705  of the sleeve  702  so that the sleeve tends to deform radially inwards. This enables the portion  714  to come into position against the plate  700  of the spacer. This is the position shown in  FIG. 11 . The spacer is prevented from being withdrawn by the shoulders of the catches  705 . Nevertheless, it will be understood that by pressing against the button  72  in the direction of arrow a, its partition  720  comes to bear against the catches  705 , and more particularly against their chamfered flats. This causes the branches  703  to move radially by titling inwards. This enables the spacer  71  to be released and thus also the element  5  which is associated therewith. 
         [0100]    This type of hinge mechanism, like the above-described mechanism, makes it possible to pivot the elements relative to each other. Merely by pressing on the button, it also makes it possible to separate them from each other, in particular for cleaning purposes. 
         [0101]      FIGS. 13 to 17  show another embodiment of the hinge mechanism between the two barrier elements. 
         [0102]    This mechanism comprises in particular an outside cap secured to the element  5  and given numerical reference  80 . This cap is received in a countersink provided in the thickness of the element. It is constituted by a generally cylindrical piece of molded plastics material having an outer circular wall  800  of small thickness. 
         [0103]    This wall has radial partitions attached thereto, there being seven such partitions referenced  801 . These branches converge towards the center of the part and they join a central ring  802  of small diameter which defines an inside space  803 . An opening  805  is provided in the thickness of the wall  800 , giving access to a housing  804  which extends diametrically and which crosses part of the inside space  803  of the central ring  802 . 
         [0104]    The mechanism further comprises a pin  81  having a head  810  in the form of a disk and an axial rod  811 . Close to its free end, the rod has a peripheral groove  812 . It is positioned in such a manner that when the pin is engaged on the element  5 ′, the groove lies inside the above-mentioned housing  804 . 
         [0105]    A cap  82  covers the pin  81  and occupies a position that is flush with the element  5 ′. 
         [0106]    The outside cap  80  is suitable for receiving a blocking element  83  via the opening  805 , which blocking element is constituted by a curved resilient clip  831  analogous to a hair pin, with one end having a head  830  for grasping. 
         [0107]    When the blocking element is engaged in the opening, a zone of the clip  831  is received inside the groove  812  of the pin  81  so as to prevent it being withdrawn from the outside cap. This is the position shown in  FIGS. 15 and 16 . Thus, when the spring clip is in position, the elements  5  and  5 ′ can pivot relative to each other. When the clip is extracted by pulling on its head  830 , it becomes possible to disengage the pin  81  and to separate the elements  5  and  5 ′. 
         [0108]    In the embodiment of  FIGS. 18 to 23 , the hinge mechanism comprises an outside cap  90  mounted on the element  5 ′. It comprises a plate  900  of circular outline with four screw-fastening orifices. This plate has a low cylindrical wall  901  in a centered position. 
         [0109]    Two tabs extend from the wall so as to face each other, i.e. they are diametrically opposite. They are attached to the wall, substantially halfway up it. 
         [0110]    The tabs are L-shaped, each having a base limb  903  connected to the wall and extending parallel to the plate  900 . The axially-extending limb  902  of each L-shape projects in the same direction as the wall and is of a curved shape, which means that these two limbs occupy a cylinder centered on the axis of the part. 
         [0111]    A part referred to as an “angular sector”  91  is engaged in the cap. 
         [0112]    This part comprises a cylindrical body  910  of diameter corresponding to the inside diameter of the geometrical cylinder defined by the two limbs  902 , ignoring clearance. 
         [0113]    One end of this body carries a coaxial head  911  in the form of a cylinder of smaller diameter. 
         [0114]    The opposite end of the body is connected to a flat plate  912  which extends in a diametral direction. The central portion  915  of the plate is circular, and it carries lugs  913  and  914  in the form of sectors of a ring. Overall this gives the plate a shape that is reminiscent of a bow tie. 
         [0115]    The angular sector is engaged in the cap  901  via the space left empty between the limbs  902  until the plate  901  comes into contact with the plate  900 . 
         [0116]    It is then possible to turn the angular sector with the plate  912  being guided and held axially by the tabs  902 . 
         [0117]    A helical spring  94  is received in the gap between the spacer  910  and the tabs  902 . 
         [0118]    The assembly is covered by a spacer  92  in the form of a cylindrical sleeve which is fixed to the element  5 ′. 
         [0119]    Its base  920  bears against the plate  900 . At this level, its inside diameter is selected to be equal to the outside diameter of the wall  901 , ignoring clearance. 
         [0120]    The spacer  92  has an inside shoulder  921  which comes into abutment against the top of said wall. 
         [0121]    Finally, its end remote from the base  920  is shaped like a cylindrical chimney  922  providing guidance in rotation for the sector  91 . The spring  94  bears against the spacer, immediately behind the chimney. 
         [0122]    The last part of this assembly is constituted by an inside cap  93 . It is provided with a low cylindrical wall which is received in the chimney  922  and which constitutes an abutment in sliding for the sector  91 . It is also provided with a peripheral flange  931  which presses against the spacer. 
         [0123]    As constituted in this way, the mechanism serves to hinge the two barrier elements around the part  91 . This part is constantly held inside the cap  90  under the effect of the spring  94 . 
         [0124]    Nevertheless, by causing the elements to pivot in such a manner that the lugs  913  and  914  are no longer in register with the tabs  902 , it becomes possible by applying traction to the element  5 ′ to overcome the force of the spring  94  and to move the element  5 ′ temporarily away from the element  5 . This gives access to the gap between them in order to clean them locally. 
         [0125]    The hinge means are preferably selected in such a manner as to leave as little space as possible between the two elements in normal operation so as to ensure that even a child cannot slide a finger between them. This makes it possible to avoid any risk of a pinching accident, particularly when moving the elements. 
         [0126]      FIGS. 24 to 27  show a system that makes it possible when the barrier elements are in the overlapping position, whether above or below the bed plane, to avoid any involuntary movement that might bring them into a position other than the desired position. 
         [0127]    This system is shown in simplified form in the above-mentioned figures. 
         [0128]    In these figures, reference  500 ′ designates the main, central arm that forms an integral portion of the above-mentioned deformable parallelogram system  50 ′. 
         [0129]    The barrier element  5 ′ is hinged to the top of this arm about an axis  501 ′, while the arm itself is hinged relative to the base structure of the bed about a parallel axis  502 ′. 
         [0130]    Reference  211  designates a part that is secured to the base structure of the bed, which part comprises in two distinct zones respective openings  212  and  213  associated with respective abutments  214  and  215 . 
         [0131]    The central arm  500 ′ is hollow and a safety catch  503 ′ can slide in its end. This safety catch is connected to a cable  504 ′ represented in  FIGS. 25 and 27  by dashed lines. 
         [0132]    A remote control mechanism (not shown) enables the cable to be pulled to actuate the safety catch. 
         [0133]    In the position of  FIG. 24 , the elements extend above the hard plane of the bed and the safety catch is engaged in the opening  212  of the part  211 . In order to unlock the elements while in this position, it is necessary to act on the cable  504  to extract the safety catch from its housing. 
         [0134]    When in the retracted position beneath the hard plane of the bed, the safety catch is received in the opening  213 , and in that case also it is necessary to act on the cable  504 ′ in order to change position. 
         [0135]      FIG. 25  shows an additional opening  216  and an additional abutment  217  on the part  211 . They enable the elements  5  and  5 ′ to occupy an intermediate locked position between the positions described above. More precisely, this is a position in which the elements are spaced apart from the bed and extend in part above the bed plane. This position is particularly suited for enabling the patient to take hold of a handle situated beside the axis XX′ and to pull on the handle in order to get out of bed. 
         [0136]      FIGS. 28 and 29  show the actuator means that enable traction to be applied to the cable  504 . These means comprise a control constituted by a button B that is movable in a slideway A fixed to the element  5 ′. The button receives the end of the cable  504 ′ which actuates the mechanism for retracting the barrier. 
         [0137]    The control is positioned in such a manner that it is not directly accessible for the patient, since it faces outwards. In addition, it is positioned in such a manner that the button B is accessible only when the elements are in the overlapping position, as shown in  FIG. 29 . 
         [0138]      FIG. 7  shows a mechanism  56  which is described below and which makes it possible to unite the two barrier elements when they are in the mutually overlapping position. 
         [0139]    In this position, and as can be seen in  FIGS. 1 ,  2 , and  7 , the barrier elements are contiguous with each other, and they occupy substantially the same amount of space as a single element. 
         [0140]    This position is particularly preferred when the patient desires to avoid any danger of falling, while still being able to sit on the edge of the bed. Indeed sitting on the edge of the bed is made easier by the patient taking hold of the barrier elements. 
         [0141]    In the embodiment shown in the accompanying figures, except in  FIGS. 30 and 31 , the bed plane  2  is fitted longitudinally with a rail  6 ′ for co-operating with one of the barrier elements. It is situated longitudinally on the side of the bed, on the portion  20  of the bed plane opposite from the portion carrying the retraction equipment  50 ′. 
         [0142]    This rail is constituted by an upside-down U-shaped meal bar whose two parallel vertical limbs  60 ′ are joined to the bed plane by a respective horizontal end portions that are not visible. 
         [0143]    The bar  61 ′ uniting them thus extends longitudinally and horizontally along the bed plane. 
         [0144]    The mechanism  56  for locking together the two barrier elements can be seen more particularly in  FIG. 32 . It comprises an orifice  53  passing through the thickness of the element  5  and receiving from the outside of the bed a button  54 . This button has a rod which passes through the thickness of the element  5  and comes out the opposite side. 
         [0145]    At this level, the rod receives a catch  55  which is generally T-shaped. The upright of the T-shape co-operates with the rod of the button, while its two perpendicular cross-bar portions  551  are disposed vertically on the side of the element  5 . Each cross-bar portion co-operates with the associated element  5  to leave an empty jamming space. 
         [0146]    When the two barrier elements are overlapping one on the other ( FIG. 7 ) it is possible to lock them together by bringing the catch  55  so that one of its cross-bar portions  551  pinches the top edge of the element  5 ′. 
         [0147]    When the two elements are in the deployed position, i.e. when they occupy a parallel position substantially in line with each other ( FIGS. 3 and 6 ), it is the opposite cross-bar portion of the T-shape which co-operates with the base  60 ′ of the guide rail  6 ′. 
         [0148]    The rail performs a first function which is an abutment function in which it prevents the barrier element  5  from pivoting below the level of the bed plane. 
         [0149]    Nevertheless, it also performs a second function which is to guide the element  5 ′. 
         [0150]    Thus, when the head portion  21  of the bed plane is raised ( FIGS. 4 and 5 ), it moves the set of elements  5  and  5 ′ longitudinally towards the foot of the bed. As a result, when the two elements are in the deployed position ( FIG. 5 ), the rail  6  serves not only to press against the element  5 , but also to guide it longitudinally as a function of the position of the bed plane. Furthermore, when the bed plane is returned to the strictly horizontal position, the barrier element  5  can be seen to move along the rail  6 ′. 
         [0151]    It should be observed that the operation of tilting the barrier elements to go from one position to the other is very easy to perform since it suffices to take hold of the outer element  5  and cause it to pivot about the axis XX′. The double-headed arrows in  FIG. 3  illustrate these movements. In addition, large handle-forming notches are provided in this case in the thickness of the elements, in order to make these operations even easier. 
         [0152]    In the embodiment of  FIGS. 30 and 31 , the bottom portion of the element  5  comprises a longitudinally extending element of smaller thickness referenced R. The base structure of the bed includes a stand P projecting towards the outside of the bed so as to be situated vertically beneath the element  5 . Its top portion constitutes a slideway G in which a handle N is hinged. 
         [0153]    The shape of the portion R of the element  5  is complementary to that of the slideway. 
         [0154]    When the element  5  is deployed, the portion R clips automatically into the slideway and in order to release the element it is pulled upwards while actuating the handle N. 
         [0155]    Thus, in operation, when the various portions of the bed are moving, the element  5  implements longitudinal displacement by the portion R sliding in the slideway. 
         [0156]    The bed shown in part in  FIGS. 34 and 35  has a frame C fitted at one of its ends with a bed head panel  4 . At the opposite end, a bed foot panel  4 ′ is secured to an assembly suitable for supporting the legs of a patient in different orientations. 
         [0157]    The frame C receives the hard bed plane which is constituted in this case by four distinct elements  20 ,  21 ,  22 , and  23 . The element  20  is secured to a torso-lifting mechanism capable of occupying various horizontal positions (see  FIG. 35 ). The element  21  is stationary while the element  22  is hinged thereto about an axis YY′ that is generally horizontal and extends transversely relative to the longitudinal axis of the bed. Thus, it can occupy positions that are not horizontal. Finally, a last element  23  is secured to the above-mentioned leg-raising assembly. 
         [0158]    A bed head barrier element  5 ′ is hinged to the bed plane element  20 . This element is secured to a retraction mechanism  50 ′ of the same type as that described above. 
         [0159]    As in the examples described above, a barrier element  5  is hinged to the element  5 ′ about an axis XX′ that is generally perpendicular to the longitudinal axis of the bed. 
         [0160]    The element  5  is hollow and an additional barrier element  5 ″ is received inside it. By pulling on this additional element in the direction of arrow j ( FIG. 34 ), this element is caused to rest on a locking device  230  fitted to the element  23  of the bed plane. This device is preferably fitted with a pivot and support pin  231  such that regardless of the respective orientations of the elements  20  to  23 , the barrier element  5 ″ might possibly slide, but always while being supported on the device  230 . 
         [0161]    In addition, the element  23  may be provided with an integral extension (not shown) e.g. having a length of 18 centimeters (cm). 
         [0162]    The element  5 ″ can then slide simultaneously with the element  23  being extended, thus adapting it to the length of the bed. This makes it possible to provide the patient with continuous protection, regardless of the orientations of the portions  20 ,  22 , and  23 . 
         [0163]    By means of this system combining hinged and sliding barrier elements, it is possible to provide protection beside substantially the entire length of the bed, which is particularly reassuring both for the patient and for hospital staff. 
         [0164]    When the barrier elements are in the erect position, a space is released beneath the bed plane going from the element  5 ′ to the locking mechanism  230 , and this occurs regardless of the position of the bed and of its barrier elements. 
         [0165]      FIGS. 36 to 38  show a retractable support part for the element  5 , constituting a variant embodiment of the above-described foot P. 
         [0166]    This part is situated along one of the bars  20  and projects transversely relative to the bed. It is constituted by a pair  220  of stationary lugs  221  and by a flap-forming element  230 . 
         [0167]    The lugs  221  extend parallel to each other transversely and vertically relative to the bar  20 . On top and close to the bar  20 , they carry a pin  222  parallel to the longitudinal axis of the bed. Further down and away from said bar, each of them is pierced by an opening for passing a locking pin  240 . 
         [0168]    This pin is constituted by a cylindrical rod  241  and by an actuator button  244 . They are separated by a cylindrical sleeve  243  which is integral with the button and of a diameter that is greater than that of the rod  241 . This rod extends between the lugs, while the button  244  and the sleeve  243  lie outside the zone between them. Finally, the free outside end of the rod  241  is terminated by a tip  242  of small diameter which passes through the corresponding lug opening provided for this purpose. 
         [0169]    The rod  241  has a helical spring secured thereto (not shown) tending to urge said rod into the position shown in the figures, i.e. with the cylindrical sleeve  243  pressing against the first lug and the tip  242  engaged in the opening in the second lug. 
         [0170]    A flap-forming element  230  is hinged to the lugs. This element comprises two parallel branches  233  and  234  interconnected by a solid part  232  having two parallel partitions  232 ′. 
         [0171]    The branches are hinged to the lugs about the pin  222 . They are spaced apart slightly wider than the lugs. 
         [0172]    The branch  233  has a notch  235  opening out upwards. The “bottom”  237  of this notch is circular and its diameter is equal to the diameter of the sleeve  243 , ignoring clearance (see  FIG. 37 ). Nevertheless, the width of the notch tapers close to its bottom so as to constitute a constriction  236  whose opposite edges are spaced apart by a distance that is smaller than the diameter of the bottom  237 . 
         [0173]    Finally, the solid part  232  interconnecting the branches  233  and  234  is constituted by two parallel plates  232 ′ having a space left between them for receiving the bed barrier element  5 . 
         [0174]    In the position of  FIGS. 36 and 37 , the support part is suitable for receiving the element  5  which presses against that part  232  between the plates  232 ′. 
         [0175]    Nevertheless, when the two elements overlap each other, the part  232  can hinder a patient attempting to get out of bed. 
         [0176]    It is then useful to be able to retract the flap  230 . 
         [0177]    For this purpose, the button  244  is grasped and traction is applied. This has the effect of moving the sleeve  243  away from the bottom  237  of the notch  235 , thus releasing the flap  230  since the constriction  236  is no longer held by the sleeve. 
         [0178]    This traction also has the effect of disengaging the tip  242  from the orifice  238  in the branch  234 . Consequently, the flap can tilt about the pin  222 . 
         [0179]    As soon as traction on the button  244  is released, it returns to its initial position. 
         [0180]    In order to return the flap to the erect position, it suffices to lift it manually and to pull on the button so as to be able to lock the two branches  233  and  234  together. 
         [0181]    The retracted position can also be useful when the bed needs to be moved out from a room. When retracted in this way, the risk of the flap striking against a wall or a door frame is reduced.
A bed comprises a head end, a foot end, first and second sides and a deck which includes, a head section and a foot section. The head section is pivotable. Head end and foot end barriers ( 5', 5) are positioned along one of the sides, and both barriers are adapted to move between raised and lowered positions. The head end barrier is moveable with the head section as the head section pivots. When both barriers are raised 1) the foot end barrier ( 5) extends footwardly beyond the head end barrier ( 5 '), 2) a portion of the head end barrier and a portion of the foot end barrier overlap each other over a portion of their longitudinal extents at all pivoted positions of the head end barrier, and 3) the overlapped portion of the head end barrier is laterally between the deck and the overlapped portion of the foot end barrier.