Abstract:
A hammock design which provides increased lifting at its mid-length or medial portion through a combination of wide bands of fabric in a lengthwise X-shaped formation with a curved or bent spreader bar. In a preferred use, the spreader bar rises from a lower middle part toward higher raised ends. This hammock allows the user a comfortable positioning with nearly horizontal transverse support at the users shoulders and a nearly level position from head to toe.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority from provisional U.S. Patent Application 61/271,264, filed Jul. 18, 2009. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to hammocks, particularly one in which an occupant is supported by material suspended between at least two points. An occupant suspended above the ground in a hammock may rest from a few hours for daytime napping up to a full night sleep in places where the hammock is a substitute for a bed, such as a board ship or in some countries. 
     Hammocks in general have been used for thousands of years, however most recent improvements appear in the last 100 years. 
     Prior art patents show different concepts and inventions related to increase level surface, spreader bar improvements, variable tensioning of fabrics, specific fabric shapes and asymmetric position of fabric and spreader bars. Graham&#39;s U.S. Pat. No. 645,805, Potter&#39;s U.S. Pat. No. 717,119, Hall&#39;s U.S. Pat. No. 4,001,902, Fueslein&#39;s U.S. Pat. No. 4,021,868, Scott&#39;s U.S. Pat. No. 6,347,638, Eriksen&#39;s U.S. Pat. No. 6,701,549, Hennessey&#39;s U.S. Pat. No. 6,865,757 and Helsdon&#39;s U.S. Pat. No. 7,020,915 each show improvements to hammocks. These patents show various ways to achieve some improvement of comfort as less curvature lengthwise for the occupant usually at the detriment of the lateral flatness of the hammock. Some others are keeping the lateral flatness to the detriment of a multi-steep flatness lengthwise. 
     Most hammock materials used today have a strong longitudinal strength with low elongation of around 2 to 5 percent in that direction which allows a person to lie in the hammock and be well supported, especially if a pre-tension of 20 to 100 lbs is made upon installing the hammock. 
     Many hammocks are so concave from side to side that any field of vision horizontally is gone and the occupant is constrained to resist a high level of side to side pressure. 
     A final and important drawback to most patents using only a two-ring support system, is when a higher tension is applied on the rings in order to improve the level lengthwise, a similar decrease of stability is brought about making it nearly impossible to stay on the hammock. 
     BRIEF SUMMARY OF THE INVENTION 
     It is therefore a foremost object of this invention to provide a hammock where the supporting surface is substantially level both lengthwise and laterally at the upper body level where the occupant lies on the hammock for pleasure or sleeping purposes. 
     A second object of this invention is to provide a low cost but sophisticated fabric support system which is easy to use either recreationally or under more tension such as sleeping surface including a three point anchoring design allowing lengthwise level and high stability combined with ease of installation. 
     A third object of this invention is to provide a fabric structure with two wide bands in an X formation, which supports the weight of the occupant exactly where it is more concentrated, from ⅓ to ⅔ of the hammock in its center as shown later on line force diagram,  FIG. 4A . 
     A fourth object of this invention is to provide improved tensioning including non-linear, curved or bent spreader bars, the positioning of which can provide a near-level surface for the occupant. This elevation of the bar ends, which work similarly as a suspended bridge, allows easy adjustment of the hammock tension, comfort and level degree as desired. 
     Several other objects and advantages of this invention are to provide lateral stability through double anchoring at one end of the hammock via a single tree or post with a triangle or a spreader block which allows a two point anchoring system; a second way to achieve this stability is to provide one of the spreader bars with two clip-on legs free to rotate and hold either end from leaning side to side. 
     It is understood that 3 or 4 points anchoring is preferable, when possible. Use of this hammock in a house would preferably be fixed solid at the head with a double short anchoring system which allows tensioning while preserving full stability. 
     The preferred embodiments of the invention have been described; however, several other embodiments based on the broad designs and configurations of the present invention are contemplated within the scope of the claims presented below. 
     A first non-illustrated arrangement is the solid attachment of one spreader bar directly onto a bedroom wall, a ship partition or an outdoor hammock support. In such a situation, only one end would require a variable length attachment which can include a one or two ring structure, or not. 
     Another non-illustrated arrangement of the hammock is where the rectangular fabric flap would be self supporting without any attachment to the spreader bar; in this case, the fabric lateral strength combined with a certain extra length of fabric and an appropriate hem with or without rope into the hem would provide the basic comfort required. 
     A third arrangement is where the larger diagonal fabric band would include a certain degree of looseness at the location of the head and the feet. 
     Several other arrangements are possible through using the basic elements of the first embodiment and integrating these into the other embodiments especially the third and fourth. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a top view of the hammock which forms the first embodiment when combined with  FIG. 2B . 
         FIG. 2A  is a top view of the diagonal fabric bands of  FIG. 1 . 
         FIG. 2B  is a top view of the upper fabric layer fastened to  FIG. 1  in order to complete the first embodiment. 
         FIG. 3  is a side view of the first embodiment combining  FIG. 1  and  FIG. 2B . 
         FIG. 4A  is a perspective view of the line of force acting in between support, spreader and fabric of the 1st embodiment. 
         FIG. 4B  is a perspective view of a prior art line of force. 
         FIG. 4C  is a perspective view of another more recent prior art showing the line of force. 
         FIG. 4D  is a side view drawing of a photograph taken from a prior art patent  4 C. 
         FIG. 5  is a top view of preferred and second embodiment of the Comfort X Hammock. 
         FIG. 6A  is a side view of the second embodiment shown in an unloaded position. 
         FIG. 6B  is the same as  FIG. 6A  except it is loaded (i.e. with an occupant). 
         FIG. 7  shows a top view of a double wide hammock made compact by overlapping the diagonal fabric band at the center of the hammock. 
         FIG. 8  is a schematic view of a third embodiment built with only two pieces of fabric. 
       LIST OF REFERENCE NUMERICALS 
       
           
             10  single wide hammock  62  sew line 
             12  spreader bar  64  sew line 
             14  spreader bar  66  sew line 
             16  large band of fabric  68   
             18  large band of fabric  70  force line 
             20  sew line  72  force line 
             22  loop  74  force line 
             24  loop  76  force line 
             26  sew line  78   
             28  sew line  80  hammock 
             30  single ring  82  force line 
             32  supporting ropes  84  spreader bar 
             34  anchor holes  86  force line 
             36  double rings  88  spreader bar 
             38  supporting ropes  90  force line 
             40  anchor holes  92  hammock 
             42  fabric end  93  edges webbing 
             44  fabric end  94  transversal line 
             46  material holes  96  spreader bar 
             48  material holes  97  spreader bar 
             50  rectangular fabric  98  force lines 
             52  medium width hem  100  force lines 
             54  adjustable flap  102   
             56  sew line  104   
             58  variable length rope  106   
             60  fix flap  108   
             110  ComfortX Hammock  145  two hooks 
           
             112 
             146 
           
             113  spreader bar  148   
             114  spreader bar  150   
             116  fabric band  152   
             118  fabric band  154  rectangular fabric 
             120  sew line  156  flap 
             122   157  sew line 
             124  sew line  158  rope 
             126  sew line  160  flap 
             128  sew line  161  sew line 
             130  ring  162  ring 
             131  ropes  163  an opening 
             132  ropes  164  sew line 
             133  ring  166  sew line 
           
             134 
             168 
           
             135  rope  170  double wide hammock 
             136  spaced rings  172  diagonal band 
             137  lower center holes  172   1  diagonal band 
             138  series of ropes  173  triangle section 
             139  tree  174  diagonal band 
             140  holes  174   1  diagonal band 
             141  spreader block  175  triangular section 
             142   176  double curve bar 
             143  bungee cord  177  four holes 
             144   178  straight bar 
             179  series of holes 
           
             180 
             210 
           
             182  locking device  212  fabric end 
             183  tension ropes  214  sew line 
             184  tension ropes  216  double flap 
             186  double fabric  218  fabric ends 
             188  four ropes  219  cut off line 
             190  two rings  220  sew line 
             192  collapsible triangle  221  group of ropes 
             194  two hanging hooks  222  fabric loop 
             195  recess hub section  224  fabric end 
             196  two hinges  226  sew line 
             197  clip-on legs  228  sew line 
             198  tree  230  series of ropes 
             200  fourth embodiment  232  sewing line 
             202  diagonal fabric band 
             204  diagonal fabric band 
             206  double bend spreader bar 
             208  straight spreader bar 
         
      
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring initially to  FIGS. 1-3  described in detail a first embodiment of the present invention in an exploded and side views:  FIG. 2B  is shown separately of  FIG. 1  details in order to provide more clarity to the embodiment description, whereas  FIG. 3  is showing the full embodiment as a side view. 
     In  FIG. 1 , the Comfort X Hammock is a single wide hammock  10  supported by a spreader bar  12  and  14  supporting two large bands of fabric  16  and  18  in a double diagonal position (making an X shape) providing approximately 70 to 100% of the lifting load of the hammock. The fabric  16  and  18  is fastened at its ends by making a loop  22  and  24  around the spreader bars  12  and  14  and being sewn to itself at line  26  and  28 ; the lateral movement of the fabric is prevented by a series of supporting ropes  32  and  38  which goes through both the fabric  16  and  18  and bars  12  and  14  through a series of anchor holes  34  and  40 . In this first embodiment the ropes  32  are secured to a single ring  30  suitable for attachment to a fixed object; at the other end of the hammock, the support ropes  38  are fastened to a double rings  36  in order to provide extra stability to the hammock and form a three point suspension or simply to have the diameter of a tree acting as a stability factor. 
     As best seen in  FIG. 2 , the fabric band  16  and  18  at loop  24  is pulling in a straight line (90 degrees) with the fabric, therefore minimum or no lateral force is involved at the loop line  24  and fabric holes  48 ; this is the reason why the spreader bar  14  has a double bend of approximately 15 degrees each in order to take maximum advantage of the straight line high strength and low stretching yield fabric use for this hammock. 
     The straight spreader bar  12  can achieve an acceptable tensioning of the fabric at loop  22  and through a series of fabric holes  46  as shown in  FIGS. 1 and 2A ; however, the near 15 degrees of side pull result is that the fabric will try to slide towards the center of the hammock; therefore, the number of fabric holes and securing ropes through the spreader bar will need to be increased. Both fabrics  16  and  18  lengthwise end at line  42  and  44  also seen in  FIG. 1 . 
     Described in  FIG. 2B  is an upper rectangular fabric  50 , this fabric is also a low yield stretching material in order to complement the diagonal band and support approximately 30% of the occupant&#39;s weight; it also gives a complete bedding to support the arms, head, and feet of the user. On each side of this fabric  50  is a medium width hem  52  sewn to itself and to fabric  16  and  18  at each ends. The strongest tension in fabric  50  is at sewing lines  26  and  28  to the fabric band  16  and  18 . An adjustable flap  54  sewn to itself at  56  is supported by a variable length rope tie to the spreader bar  12 . At the other end a fix flap  60  is sewn to itself at line  62  and provide a more level and comfortable support position for the user. Additional strengthening of the hammock bedding is provided by the sewing lines  20 ,  64 , and  66  which prevents the diagonal band  16  and  18  from shifting laterally under tension when the hammock is in active use. 
       FIG. 3  is showing a side view of the combination of  FIGS. 1 and 2B  where the upper fabric  54  lays on top of the diagonal band  16  and  18 , all sewn together at  26 ,  28 ,  20 ,  64 , and  66 ; the fabric  16  and  18  is shown making a loop around spreader bar  12  and  14  which are tied to ring  30  and  36  by the rope  32  and  38  passing through the spreader bar at holes  34  and  40  and the material holes  46  and  48 . As it could be seen in this side view the double angle bar  14  is laying in a near horizontal position since the rope  38  is free to equalize the tension between the outer and the inner attachment holes  40 . 
     The spreader bars are either made of wood which permit to easily provide drilled holes for the fastening of the ropes and the fabric supporting the load of the hammock. The double angle bar shown in this first embodiment is also easily done with wood since vapor bend wood is intensively used in building furniture and presents a low-cost eco-friendly and strong component as a multi-curve spreader bar. Choice of other materials such as steel or aluminum tubing can also be used, these materials would require the insertion of hollow thin material type rivets in order to form abrasion, and sharp edged free anchoring holes. Composite material such as fiberglass could also qualify, but same as metal it would present a cost and manpower handicap over a wood bar with only a small gain in lightness, appearance, and durability. 
     Referring to  FIG. 4A  the perspective drawing shows the lines of force going through the basic embodiment of the invention with force line  72  and  74  going across each other at 30 to 35 degrees and transmitting the load to the spreader bar  12  and  14 , then the line force  70  and  76  are being carried by ropes  22  and  38 . 
     This diagonal flow of the line force is the reason the embodiment permits this level of longitudinal and transversal support where previous hammock failed since near all fabrics strength is straight and cross-wise at 90 degrees. 
       FIG. 4B  is a schematic of the parabolic force lines of a hammock of prior art as shown in the literature; the hammock  80  has force line  82  tied to spreader bar  84  and  88  and is supported by force line  86  and  90  representing the ropes and rings. 
       FIGS. 4C and 4D  show a more recent prior art which uses a combination of outer edge support webbing and transversal strength of the fabric in order to achieve a more level support of the users. In this schematic of the support line of hammock  92 , the fabric transversal line  94  is transmitting the support action to the edges webbing  93 , and spreader bars  96 . Spreader bars  96  and  97  are ties to ropes and rings represented by force lines  98  and  100 . It can be seen that the combined concavity of webbing  93  and transverse fabric line  94  allow, for a level longitudinal levelling at the drawback of being enclosed into a deep transversal cocoon which does not provide much or any amount of comfort and relaxation. 
       FIG. 4D  is showing more specifically that the user of the prior art  4 C is laying near level lengthwise; however as it can be seen, the fabric is surrounding his body near completely, which means the user&#39;s shoulders are forced into a round support position which is similar to the “banana hammock” or laying in the bottom front or rear of a canoe; this and the near total cut-off of peripheral vision is the extreme opposite of what a comfortable relaxing outdoor enjoyment could be. 
       FIG. 5  detailed the preferred embodiment of the Comfort X hammock  110  where a spreader bar  114  is built with a single bend having an approximate radius of five feet in order to promote a near perfect pull onto a fabric band  116  and  118 ; a second spreader bar  113  is also made with a single bend radius of only three to four feet because this bar holds a vertical position as seen in  FIG. 6A , and therefore only a partial part of the bend is given for the fabric alignment. Similarly, as in  FIG. 1 , the fabric band  116  and  118  looped around bars  113  and  114  and sewn to itself, covering the diagonal fabric band is a rectangular fabric  154  at a sew line  126  and  128 . Each end of the fabric  154  includes a flap  156  and  160  looped around a rope  158  and  162  sews to itself at  157  and  161 ; the ropes  158  and  162  are tied around the spreader bars  113  and  114 . These flaps are located for the head and the feet, are adjustable by tightening or loosening the ropes  158  and  162 . The spreader bar  113  is supported by a ring  130  via a series of ropes  132  tied to the upper ends of bar  113  and another rope  131  which is adjustable at ring  133  which carries the load of the lower center holes  137  via the rope  135 . The reason for the separate and adjustable ropes support system is in order to be able to “dial” how much support the occupant wants for the lower back or the upper body. Spreader bar  114  is supported at the other end by a series of ropes  138  looped into the widely spaced rings  136  to hold onto a tree  139  which holds spreader block  141  which has two hooks  145  anchoring the rings  136 . The hammock  110  also provides, through fabric  154  an opening  163  which allows the occupant to lay face down and breathe easily with the head and body in line. 
       FIG. 6A  is a side view of  FIG. 5  of the preferred embodiment of the invention; the hammock is shown in a relaxed position with fabric band  116  and  118  edges in a near straight line position; fabric  154  follows a more convolute shape since the outer edges of band  116  and  118  are located 4 to 6 inches higher than their inner edges at the spreader bar  113  and then they criss-cross each other before they reach the other end at spreader bar  114 , therefore developing a staggered lift especially strong from ⅓ to ⅔ the length of the hammock bed. 
     Supporting the spreader bar  113  is the ring  130  with ropes  132  tied to the upper end of the bar  113  and the rope  131  and  135  via ring  133  tied to the lower center section of the curved bar  113 . At the other end of the hammock, the ropes  138  are tied to the rings  136  at one end and through holes  140  through fabric band and spread bar  114 . Side views provide a precise view of how a flap  156  is linked to the spreader bar with a rope  158 . Same scenario at the other end with a flap  160  supported at its end by a rope  162  tied to the spreader bar  114 . 
     The side view  FIG. 6B  is showing the same hammock as loaded by an occupant (not shown), and is based on the testing of several prototypes. The description is similar as  FIG. 6A  except that the loaded diagonal bands  116  and  118  are now lower by six to eight inches which is about only one-half what a current hammock does as in  FIG. 4B  under a same occupant weight. 
     As seen in  FIG. 6A , the two flaps are around three to four inches lower than the bedding, now under load as shown in  FIG. 6B , the two flaps are now nearly horizontal with the whole bedding and provides a near level surface from feet to head. 
     The two point support at rings  136  can be provided by a single tree with the spreader block  141  made of wood reinforced with an outer strap or wire of metal tie to the front hooks  145 . The bungee cord  143  is used to hold the block  141  during the initial set-up, only because once the hammock is under a tension of two to four hundred pounds, the block then is stable by friction to a very high degree. 
       FIG. 7  is showing a third embodiment of the invention as a partial top view of a double wide Comfort XX hammock as  170 ; in this hammock, the upper rectangular fabric is omitted in order to allow more clarity of the lower diagonal bands which are shown as a cut-off section for the same reason. This embodiment shows a first diagonal band  172  which forms a wide X with a second diagonal band  174 ; a second wide X is formed by a third diagonal band  172 ′ crossing over a fourth diagonal band  174 ′. Both bands  172  and  172 ′ overlap at a triangular section  173 , therefore reducing the width of the hammock; similarly, the bands  174  and  174 ′ overlap at a triangular section  175 . 
     Other components of the hammock have similar characteristics as previous embodiment such as a double curve spreader bar  176  similar to bar  113  of  FIG. 5 , and a straight spreader bar  178  which provides the same function as spreader bars  12 ,  14  and  114  since all those bars are positioned in a horizontal plane including the curved section in bar  114 . It should be noted that the horizontal plane bar end of the hammock is preferred for the flatter fabric area it provides for the upper body of the user. This third embodiment is supported by a single ring  180  which supports a series of tension ropes  183  and  184 ; the ropes  183  are adjustable near spreader bar  176  thru a locking device  182 , all ropes tie to bar  176  and a series of four holes  177 . 
     At the other end the hammock is supported by bar  178  and a series of holes  179  with four ropes  188  tied to the two rings  190 . Located around a tree  198 , is a collapsable triangle  192 ; this allows two hanging hooks  194  to carry the pull of the hammock and a rigid two point support. The triangle  192  has at least 2 hinges  196  and can be built from tubing material and locked at the third intersection with its hook  194 . 
     An alternative method to provide roll stability is to provide the hammock with two clip-on legs  197  fastened to a recess hub section  195  as part of bar  178 . 
       FIG. 8  is a fourth embodiment  200  of the Comfort X hammock and is shown as an alternative and lower cost two diagonal fabric bands  202  and  204  slightly wider than in previous embodiment; this configuration eliminates the need for the upper rectangular fabric. This partial embodiment shows a double bend spreader bar  206  around which the fabric  202  and  204  looped around with fabric end at  212  and sewn to itself at line  214 . At mid-width, a double flap  216  from fabric  202  and  204  is looped around itself up to end  218  and sewn to itself at sew line  220 ; a cut off line  219  gives some leeway into the amount of sag provided by a group of ropes  221 . 
     At the center of the diagonal band a few sewing line  232  provides extra strength and stability to the fabric, it also allows a precise location for under knee pillow lift. The hammock&#39;s other end is shown with a straight spreader bar  208  with fabric loop  222  ending at  224  and sewn at line  226 ; center section is similar to the other end with a single layer of fabric  204  and  202  forming a flap  224  before reaching bar  208 , this fabric loop end at  226  and is sewn at line  228 ; a series of ropes  230  are fastening the flap to the bar  208 . A breathing hole  234  and surrounding sewing allows for face down use of the hammock. 
     Fabrication and assembly of this hammock is basic wood working, fabric cutting, sewing, and mostly manual assembly of the components together. Pre-production hammocks should be made in order to eliminate any production difficulty and reach a product with the correct characteristics. Assembly of the 2 or 3 layers of fabric will need to be precise enough in order to achieve shared load and stretch lengthwise but give approximately 5% extra material near the flap area at each end from side to side; this extra material is important as it permits a level support of the hammock occupant. 
     It is useful to note that these specific details to the invention embodiments are already known by the persons familiar with the construction of hammock structure and construction. 
     The many advantages which are inherent to the embodiments structure are obvious to the one skilled in the art. Those embodiments are described herein illustratively and are not meant to limit the scope of the invention, therefore variation of the basic embodiments is intended to be encompassed by the following claims.