Abstract:
A wheel chair includes wheel frames which can be adjusted up and down, moving devices and brake devices are connected to two respective sides of the two wheel frames. Support devices are connected to the wheel frames so as to adjust the depth of the wheel frames to which arm rest devices are connected. A folding device is connected between the wheel frames and an assistant device is connected to the folding device. A positioning device is connected to the assistant device so that the wheel chair can be adjusted in many ways to meet different needs of users. The modularized devices effectively reduce manufacturing cost of the wheel chair.

Description:
FIELD OF THE INVENTION 
   The present invention relates to a wheel chair that is composed of modularized units which are convenient to be assembled. 
   BACKGROUND OF THE INVENTION 
   Many known wheel chairs are disclosed such as those disclosed in DE 3742547, GB 2101540, U.S. Pat. Nos. 4,648,619, 4,721,321, 4,730,842, 5,28,183, 5,522,404, 6,296,265, 6,338,496, 6,345,833, 6,499,756, 6,499,762, 6,648,359, and 5,522,404. DE 3,742,547, U.S. Pat. Nos. 4,648,619, 4,721,321, 4,730,842, and 6,338,496 discloses wheel chairs wherein the rear wheels are pivotably connected one of multiple holes on the side frames. U.S. Pat. No. 4,721,321 discloses that the arm rests are connected to a quick release device on a side of the seat frame. U.S. Pat. Nos. 6,338,496 and 6,648,359 disclose that the arm rests are threaded to the holes in the back rest frame, the height of the arm rest can be adjusted, however, cannot be tilt. U.S. Pat. Nos. 4,730,842, 4,721,321, and 6,338,496 disclose that the front frame includes extension tubes for connecting the foot rests. U.S. Pat. Nos. 6,338,496 and 6,499,756 disclose that the foot rests are connected to the wheel frames by threaded sleeves, U.S. Pat. No. 6,499,756 employs a spring to position the foot rests which is allowed to be pivotable. U.S. Pat. Nos. 4,648,619, 4,721,321, 5,328,183, 6,499,762 and GB 2101540 disclose that the folding device cannot be disengaged from the frames. U.S. Pat. No. 5,522,404 uses a safety belt. U.S. Pat. No. 4,730,842 discloses that the arm rests are rotatably connected to the backrest frame by a special member and the foot rests can be rotatably folded but cannot provide comfortable use. The seat pad is connected to the frame by Velcro strips and the width of the wheel chair can be adjusted but cannot be folded. It is noted that the conventional wheel chairs cannot provide a wide range of adjustments to meet needs of different users. Some parts cannot be independently separated from the main frame so that a huge assembly has to be replaced in maintenance, and this spends a lot. 
   The present invention intends to provide a wheel chair which is composed of several units which are able to be adjusted according to the needs of different users. 
   SUMMARY OF THE INVENTION 
   The present invention relates to a modularized wheel chair that comprises two wheel frames, moving devices connected to two respective sides of the two wheel frames, brake devices, and support devices connected to the wheel frames. The wheel frames each include a support rod and a seat positioning portion at one end of the support rod which is connected to a post. The other end of the support rod has a front wheel positioning portion which is connected to the post by a transverse rod. The post includes two connection rods whose respective two ends are connected with each other to form a wheel frame. A shaft device is connected between the two wheel frames. The moving devices each include a front wheel unit connected to a front wheel positioning portion and a rear wheel unit connected to a rear wheel positioning member. The brake device includes a clamp member which is respectively connected to the first rod and a transverse connection member which has one end pivotably connected to a stop on the rear wheel unit and the other end of the transverse connection member is connected to a lever which is connected to the stop by a connection member. The support devices includes a seat frame which includes a plurality of positioning holes and a backrest frame includes an angle adjusting portion. The seat frame is connected to the backrest frame by a backrest frame positioning member and the seat frame are connected to two seat frame adjusting members on the support rod. 
   The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view to show the wheel chair of the present invention; 
       FIG. 2  is an exploded view to show the wheel chair of the present invention; 
       FIG. 3  shows the wheel frames of the present invention; 
       FIG. 4  shows the support device of the present invention; 
       FIG. 5  shows another embodiment of the support device for foot rest of the present invention; 
       FIG. 6  shows the folding device of the present invention; 
       FIG. 7  shows the assistant device of the present invention, and 
       FIG. 8  shows the exploded view of the protection device of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to  FIGS. 1 and 2 , the wheel chair of the present invention comprises two wheel frames  10 , a shaft device  20  connected between the two wheel frames  10 , quick release moving devices  30 , brake devices  40 , support devices  50 , arm rest devices  60 , folding devices  70 , assistance devices  80  and a positioning device  90 . 
   Referring to  FIG. 3 , the wheel frames  10  each includes an L-shaped support rod  11  and a front wheel positioning portion  12  is connected to a short section of the support rod  11  and a multiple-hole seat positioning portion  111  is connected to a long section of the support rod  11 . A plurality of positioning holes  112  are defined in the bent portion of the support rod  11  and two horizontal tubes  113  are connected on a side of the support rod  11  so as to be threaded to a connection member  13 . The seat positioning portion  111  is connected perpendicularly to a post  14  on the wheel frame  10 . The post  14  includes several splitting potions which include a transverse lower connection rod  141 , a transverse rod  15  and two cylinder positioning portions  16  having holes. The transverse rod  15  is connected to the front wheel positioning portion  12  so as to form the front section of the wheel frame  10 . 
   The post  14  has a connection rod  142  transversely extending from a middle portion thereof and a free end of the connection rod  142  is connected to a first rod  17  which includes a plurality of rear wheel upper positioning holes  171 . A shaft positioning portion  172  is connected to a short section of the first rod  17  and a second rod  18  is connected a distal end of the short section. A plurality of rear wheel lower positioning holes  181  are defined in the second rod  18  and a distal end of the second rod  18  is connected to the transverse lower connection rod  141  so as to form a stable and reliable wheel frame  10 . 
   The shaft device  20  connected between the two wheel frames  10  includes two hollow tubes  21  which are connected to each other head to tail by a plate  22 , and two respective free ends are respectively connected to the shaft positioning portions  172  so as to form a folding mechanism. 
   The quick release moving devices  30  each include a quick release front wheel unit  31 , a rear wheel unit  32  and an assistant wheel unit  33 . The front wheel unit  31  includes a front wheel frame  311  which has one end threaded to the front wheel positioning portion  12  and the other end of the front wheel frame  311  is adjustably connected to the front wheel  312  by one of the through holes thereof. The rear wheel unit  32  is connected to the positioning hole  171  and  181  of the rear wheel positioning member  321  by using quick release devices  34 . The quick release devices  34  has a biasing member  35  installed in a recess  341  defined in an end thereof and the end is inserted in the shaft and a bead  36  is received in a hole so as to be engaged with the recess  341 . By pressing the quick release device  34 , the bead  36  is moved into the hole or protrudes from the shaft. 
   The second rod  18  is connected to the assist wheel unit  33  and a straight moving wheel  331  is connected to the lower positioning hole  181  so as to increase the stability of forward movement. A free end of the second rod  18  is connected to a side moving wheel  332  so as to save efforts when moving the wheel chair a side. 
   The brake device  40  includes a clamp member  41  which includes a groove in each of two ends thereof so as to respectively connect to the first rod  17  and a transverse connection member  42  which has one end pivotably connected to a stop  43  on the rear wheel unit  32  and the other end of the transverse connection member  42  is connected to a lever  44  which is connected to the stop  43  by a connection member  45 . The lever  44  includes an incline section so as to drive the stop  43  to press the rear wheel unit  32  to brake. 
   Referring to  FIG. 4 , the support devices  50  are respectively connected to the wheel frames  10  on two sides of the wheel chair and includes an L-shaped seat frame  51 . Two foot rest locking portions  511  are connected to the short section of the seat frame  51  and a plurality of positioning holes  512  are defined in the long section of the seat frame  51 . The backrest frame  52  includes a plurality of upright tubes and an angle adjusting portion  521  are defined in a long section thereof. The backrest frame  52  includes a locking portion  522  for connecting an adjusting member  523  which has holes defined in its free end thereof, so as to form a backrest frame  52  which can be adjusted in length. The locking portion  522  is connected to a double-layer arm rest adjusting member  53  which has a threading portion  531  at its narrow end so as to be connected to the backrest frame  52 , a middle section of the adjusting member  53  includes an arm rest connection hole  532 , and an arm rest positioning portion  533  is connected to its wide end of the adjusting member  53 . 
   A backrest frame positioning member  54  includes connection holes  541  which are in alignment with the positioning holes  512  in the seat frame  51  so as to adjust the seat frame  51  forward and backward. The middle section of the backrest frame positioning member  54  has backrest frame positioning holes  542  which are connected to the angle adjusting portion  521  of the backrest frame  52  by pins  56 . By pulling the pins  56 , the adjusting member  523  can rotate the angle adjusting portion  521  to a desired position and the pins  56  are then inserted in the alignment positioning holes  542  to set the backrest frame  52  at a specific angle. The rest of the connection holes  541  are connected to the cylinder securing members  551  of the one-direction cylinder  55  which has a connection portion  252  so as to be connected with is connected to the two cylinder positioning portions  16 . 
   Two seat frame adjusting members  57  are connected with each other at a middle portion thereof and the seat frame  51  is rested in a up-facing recess of the combination of the seat frame adjusting members  57 . The bottom-facing recess of the combination of the seat frame adjusting members  57  includes a plurality of holes to be connected with the positioning holes  112  of the support rods  11 . 
   The foot rest unit  58  includes an L-shaped support rod  581  which has a pivotable portion  582  and a positioning member  583  on the foot rest locking portion  511  at a short section of the support rod  581 . A flexible fork  584  is connected to the free end of the positioning member  583  and includes two ends, one of which is connected to the seat frame  51  and the other end is connected to an activation portion  585 . When pressing the activation portion  585 , the flexible fork  584  releases the seat frame  51  and the support rod  581  can be pivoted and disengaged from the locking portion  511  so that the user may easily sit in the seat or separate the whole wheel chair. 
   An L-shaped angle adjusting unit  59  is connected to a long section of the support rod  581  and includes a U-shaped portion threaded to the support rod  581 . A plurality of holes are defined through a vertical section of the angle adjusting unit  59 . The holes are adjusted to positions where are in alignment with holes defined in a positioning member  592  threaded to the foot rests  586 , pins or bolts are inserted through the alignment holes to adjust the foot rests  586 . 
   The arm rest device  60  includes an arm rest support frame  61  with a pad  62  connected thereon, a plurality of connection holes  63  are defined in a free end of the arm rest support frame  61  so as to be in alignment with the arm rest connection hole  532 . A backrest securing portion  64  includes several curve slots defined in a free end thereof and the pins  56  are engaged with the slots so as to set the backrest  52  in different angles including a horizontal position. 
   The foot rest unit  58  can also be a one-piece foot rest  587  as shown in  FIG. 5 , the seat frame  51  includes pairs of hooking members  588  and the foot rest  587  includes holes  589  which are engaged with the hooking members  588  so that the foot rest  587  may bear a large load. When the hooking members  588  are disengaged from the holes  589 , the foot rest  587  can be disengaged from the frame. 
   As shown in  FIG. 6 , the folding devices  70  are located between the wheel frames  10  and include two crossbars  71  which are pivotably connected with each other at center holes  711  thereof. A lever  713  is connected to an end of the main frame  712  and is directly connected to the mounting members  13 . At least one set of connection member  72  are pivotably connected to an end of the lever  713  and the other end of the lever  713  is fixed to the pivotable member  73  on the transverse rod  15 . The connection portion  72  includes a porous plate-like support rod positioning portion  721  and the other end is connected with a C-clamp  722 . The two respective C-clamps  722  secure the support rod  11 . The pivotable member  73  includes a securing portion  731  which is fixed to the main frame  712  and a semi-opened sleeve  732  is connected to a free end of the pivotable member  73  so as to be connected to the transverse rod  15  with cooperation of a cap  74 . Besides, the main shaft  712  has a assistant member  75  so as to firmly combine the parts. 
   As shown in  FIG. 7 , the assistant device  80  includes a pad  81  and a head rest  82 . The pad  81  includes a board  811  with Velcro strips and holes are defined in two sides thereof so as to be connected with C-clamps  812  on the seat frame  51  or on the back rest  52 . A cushion pad  813  is attached to the Velcro strips on the board  811  to provide better cushion feature. When the pad  81  is used as a backrest and cooperated with the head rest  82 , a plurality of securing holes  814  are defined in a side thereof so as to secure a securing member  83  which includes a connection portion  831  so as to be connected to the head rest post  821  by long bolts. A free end of the head rest post  821  is pivotably connected to a free end of the transverse bar  823  of the head rest  822 . 
   As shown in  FIGS. 7 and 8 , the positioning device  90  includes a base  91  with several holes  911  in one side so as to be connected with the wheel chair and the other side of the base  91  includes a first positioning portion  912  and a second positioning portion  913  which includes a passage. The first positioning portion  912  has a recess facing the second positioning portion  913  so that a spring  92  and an end of a rotation piece  93  are received in the recess. An end of the rotation piece  93  is biased by the spring  92  and the other end of the rotation piece  93  includes positioning portions  931  to set the angular positions at 90 and 180 degrees for example. A limitation member  94  includes a cross-shaped recess and the rotation piece  93  includes a surface  932  with a plurality of threaded holes so as to be connected to the connection plate  95  secured to the protection plate  96 . The limitation member  94  is secured by the pins  97  extending through the second positioning portion  913 . The surface  932  of the rotation piece  93  may be any form other than the surface, an assistant piece  75  can be used on the cylindrical surface of the rotation piece  93 . 
   The connection plate  95  has one end fixed to the fixing portion  951  and the other end has a threaded portion  952 . The protection plate  96  has one end fixed to the connection portion  961  and includes a positioning portion  962  to guide and position the body of the user. When the protection plate  96  is used as a protection member, the connection plate  95  can be composed of multiple parts. When the protection plate  96  is used as a chest protection member, the second positioning portion  912  is oriented downward and connected to two sides of the board  811  so that when the user sits in the wheel chair, he or she exerts a force to the protection plate  96  makes sure that the rotation piece  93  on the base  91  is firmly connected to the limitation member  94  of the second positioning portion  912 . 
   While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.