Abstract:
A lifting apparatus for high-place work which includes a moving supporting leg having a guiding case with opposite open ends and plural walls, guiding grooves attached to said walls, plural elastic strips, a plurality of connecting pieces transversely attached to said elastic strips with the connecting pieces having a proportional number composed of shorter and longer lengths with the longer connecting pieces having fitting grooves on ends thereof, which matingly engage the ends of the shorter connecting pieces. The elastic strips are rotatably wound about respective winding drums disposed on the loading box of a vehicle and driven a driving force originating from the power source of the vehicle such that by unwinding the respective elastic strips an integrated column is formed at a desired elevated high location.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a lifting device for high-place work to be used for painting or cleaning work at high apartments or buildings, fire extinguishing work at high buildings, transferring work for house-moving packs at high apartment houses or buildings, checking high place traffic facilities, electric inspection or work and the like and more particularly to a lifting apparatus for elevation work which allows access to a high place by forming a continuous supporting leg with elastic strip unwound from a winding drum. 
     BACKGROUND OF THE INVENTION 
     Generally, extensible elevated ladder equipments with the telescopic structure are used in painting or cleaning work at multi-storied apartments or buildings, fire extinguishing work at high buildings, transferring work for house-moving packs at high apartment houses or buildings and the like. 
     However, for those elevated ladder vehicles with the telescopic structure, moving to an elevated position is in fact restricted due to the weight of loads, and other factors like mechanical structural features of the equipments. Therefore, conventionally in washing or painting for multi-storied buildings, workers had to conduct the job, with their bodies supported on ropes or the like hanging from the rooftop of the buildings, wherein risks of safety accidents including falls exist because of unstable state and so on. 
     SUMMARY OF THE INVENTION 
     Accordingly, the object of the invention is to provide a lifting apparatus for elevation work, wherein the disadvantages with conventional art are resolved and any elevated location is easily accessed without the restriction of height to conduct the desired work stably and conveniently. 
     The above object is achieved according to the invention by a lifting apparatus for high-place working comprising a supporting leg consisting of a guiding case in the form of a hollow rectangular box with opposite ends open, mounted at a spacing above the floor surface and provided, on its inner walls, with guiding grooves with a side open, plural elastic strips provided movably through respective guiding grooves and an upper opening from the underside of the guiding case for forming an integrated rectangular column and each having a predetermined length, and connecting pieces attached on the respective elastic strips at a constant interval over the total length of elastic strips for giving the elastic strips supporting force so as to move to a high place in the form of a rectangular column through fitting engagement of the elastic strips, the connecting pieces having different length; winding drums disposed rotatably on the floor surface at positions corresponding to the respective elastic strips in the moving supporting leg for winding the elastic strips in the form of roll; a first driving means disposed in the vicinity of the moving supporting leg for furnishing to the winding drums driving force to wind the elastic strips through an axial connection to one of the winding drums; a second driving means disposed contiguous to one of the elastic strips of the moving supporting leg at a position isolated from the first driving means for furnishing a driving force to control the movement of the moving supporting leg in relation with the operation of the first driving means; and a controlling means for controlling the switching on or off of the first and second driving means. 
     The guiding case is preferably formed of metal plates with predetermined area and the guiding grooves are provided at the top position for two opposite metal plates and at the bottom position for the other two opposite metal plates. 
     Also, preferably, the top parts of the elastic strips forming the rectangular column in the moving supporting leg are integrally combined by a wrapping frame in the form of a band. 
     Further, the connecting pieces are desirably formed of metal members with a predetermined strength and fixed transversely to the elastic strips in a detachable manner, and the connecting pieces out of all the connecting pieces exceeding the width of elastic strips in length are formed, on their opposite ends, with fitting grooves to synchronously engage and fix the ends of the shorter connecting pieces and the ends of the elastic strips attached with the shorter connecting pieces. 
     It is preferably provided that the moving supporting leg is formed, on its top end, with a working stand for high-place workers. 
     According to a preferable detail, the first driving means consists of a reversible motor and the second driving means comprises a ratchet gear rotatably mounted in the ratchet gear box which is formed, with the side toward the column open, on a side wall of the guiding case, so that the ratchet gear can be meshed in the chain provided over the full height of the elastic strip facing the gear box on the supporting leg, and a driving motor connected axially to the ratchet gear for transmitting, through a shaft, driving force to cause the meshing with the chain and for controlling the movement of the moving supporting leg. 
     Preferably, the controlling means comprises a control box having operation buttons, which allow selective on/off operation of one or both of the driving apparatuses, through an electric circuit of a power supplying battery electrically connected with the first and second driving apparatuses. 
     According to another aspect of the invention, two or more lifting apparatuses for high-place working are disposed in interlocking manner and support a single working stand. 
     The lifting apparatus for high-place working according to the invention is desirably installed on a transporting means such as a vehicle for the convenience of mobility. 
     Accordingly, as the height of the supporting leg or rectangular column can be determined by the length of the elastic strips wound on a winding drum, any high place can be approached within the strip length wound on the drum, so that the desired high-place work can be conducted stably. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows the perspective view of a lifting apparatus for high place work according to an embodiment of the invention, as mounted on a vehicle, 
     FIG. 2 shows the enlarged perspective view of the “A” portion of FIG. 1, partly cut away and partly dismantled, 
     FIG. 3 shows the enlarged perspective view of the “B” part of FIG. 2, 
     FIG. 4 shows the perspective view of the “A” portion of FIG. 1, as moved upward in upright posture, 
     FIG. 5 shows the enlarged plan view in cross section taken along the line I—I in FIG. 4, 
     FIG. 6 shows the perspective view illustrating the appearance of the winding drum shown in FIG. 1, 
     FIG. 7 shows the view, as seen from the above side, of another variant of driving apparatus employed in the lifting apparatus for high-place work according to the invention, 
     FIG. 8 shows the front view of the lifting apparatus for high-place work according to another embodiment of the invention and 
     FIG. 9 shows the plan view of FIG.  8 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Preferred embodiments of the invention will be described in detail below by referring to the accompanying drawings. 
     As shown in the drawings, the lifting apparatus  100  for elevation work according to the invention includes a moving supporting leg  200 , so that the lifting apparatus can be installed on the loading box  20  of a transporting means like a vehicle  10  for the purpose of convenient mobility. The moving supporting leg  200  which is a structure capable of moving to a high location from the loading box  20  comprises a guiding case  210 , elastic plate strips  222   a ˜ 222   d  and connecting pieces  240   a  and  240   b.    
     As may be understood from FIG. 3, the case  210  forms a rectangular box of hollow structure, with two opposite ends, for example, the top and bottom ends being open as openings  212  and  214 , is installed on the loading box  20  of a vehicle  10  at a spacing d from the floor surface of the box and is provided, on the inner walls, with guiding grooves  216  and  218  partly opened, so that the elastic strips  222   a ˜ 222   d  may be guided through the above-described openings  212  and  214 . The elastic strips  222   a ˜ 222   d  form a rectangular column, as it moves through the inside of the guiding case  210 , which will be further explained later. The guiding case  210  is formed of high-strength metal plates  211   a ˜ 211   d  having a predetermined area through the combined method of welding and clamping or the like and its size, i.e. the height and area, may vary depending on the size of the elastic strips  222   a ˜ 222   d.    
     A guiding member, e.g.  226  in FIG. 2, for forming a guiding groove  216  of the guiding grooves  216  and  218  is provided at the top inside area of each of opposite metal plates  211   c  and  211   d , while the other guiding member  228  for forming the other groove  218  is provided at the bottom area of each of the other opposite metal plates  211   a  and  211   b . The alternate provision of the guiding grooves  216  and  218  at the top and bottom areas of the metal plates  211   a ˜ 211   d  is intended to guide elastic strips  222   a ˜ 222   d  in an effective manner. The guiding grooves  216  and  218  may be either formed directly on the metal plates  211   a ˜ 211   d  or may be formed by means of separate guiding members  226  and  228  as seen in FIG.  3 . The guiding members  226  and  228  can be fixed to the metal plates  211   a ˜ 211   d  by electric welding or screw-fixing. 
     The elastic strips  222   a ˜ 222   d  are each formed of a metallic body in plate form having a predetermined bending strength, such as a general sheet metal coil. Elastic strips  222   a ˜ 222   d  with a long length are each introduced from the lower outside, by one ends, or the top ends in FIG. 2, through the gaps d between the floor surface of the loading box  20  and the lower edges of guiding case  210 , then through the lower opening  212  and guided up through the guiding grooves  216  and  218  of the case  210  up to the upper opening  214 , now as upright sheet bodies, to reach the upper outside, whereby the elastic strips  222   a ˜ 222  form substantially a rectangular column by means of the guiding case  210 , as shown in FIGS. 1 and 2. The other ends of the elastic strips  222   a ˜ 222   d  are wound and anchored, in a cylindrical form, on the circumference of winding drums  300   a ˜ 300   d , as will be further explained in the following. The elastic strips  222   a ˜ 222   d  forming substantially a rectangle form above the guiding case  210  are connected integrally on their top ends by a frame  215  to constitute an integrated rectangular column  220 , as seen in FIGS. 1 and 2, on the top of which column a working stand  700  for workers is provided. The elastic strips  222   a ˜ 222   d  are moved up and down relative to the guiding case  210  in the form of rectangular column  220 , wherein the height of the rectangular column  220  is controlled by the length of the elastic strips  222   a ˜ 222   d . The width of respective elastic strips  222   a ˜ 222   d  is so decided as to pass through the guiding grooves  216  and  218  on the guiding case  210 , and the length and thickness of elastic strips  222   a ˜ 222   d  are preferably decided to be adapted to wind around the winding drums  300   a ˜ 300   d  as will be described in more detail later, wherein the width and length of the strips may be varied in accordance to the change in the size of the grooves  216  and  218  or the change in the size of the winding drums  300 . 
     The above-described connecting pieces  240   a  and  240   b  serve to unite the elastic strips  222   a ˜ 222   d  so as to form an integrated rectangular column  220  having a firm bearing force, as the strips move out from the guiding case  210  forming the rectangular column  220 . Because the elastic strips  222   a ˜ 222   d  are united so as to form an integrated rectangular column  220  by the help of the connecting pieces  240   a  and  240   b , they can have supporting and reinforcing force large enough to move the column body  220  as moving from the case  210  firmly to a desired high position. In other words, the connecting pieces  240   a  and  240   b  are made of high strength metal members and distributed at a constant interval over the total length of the elastic strips  222   a ˜ 222   d.    
     Accordingly, in the case that the elastic strips  222   a ˜ 222   d  are moved upward under the guidance of the guiding grooves  216  and  218  on the guiding case  210 , at the instant when the connecting pieces  240   b  which are shorter than the width of elastic strips and provided on the opposite elastic strips  222   a  and  222   b  meet with the corresponding connecting pieces  240   a  which exceed the width of elastic strips and provided on the opposite elastic strips  222   c  and  222   d , as the strips move up, the elastic strips  222   a  and  222   b  together with the connecting pieces  240   b  are fitted in the structured grooves  228   a  and  228   b  formed on the opposite ends of the connecting pieces  240   a , as seen FIGS. 2 and 5, so that the elastic strips  222   a ˜ 222   d  form a continuously lengthening integrated rectangular column  220 , as they move upward through the upper opening  214  of the guiding case  210 , as depicted in FIGS. 1 and 4. Therefore, even though the rectangular column  220  is proceeding to a high elevation, the column stays upright continuously without warping to one side or bending due to the reinforcing force exhibited by the connecting pieces  240   a  and  240   b  in such a manner as to keep the elastic strips  222   a ˜ 222   d  integrated. 
     Correspondingly, when the rectangular column  220  moves down in contrast, the elastic strips  222   a ˜ 222   d  forming the column  220  are moved to the outside through the gaps d from the lower opening  212  of the guiding case  210  to be wound around the winding drums  300   a ˜ 300   d , while the connecting pieces  240   a  and  240   b  which so far have been supporting the elastic strips  222   a ˜ 222   d  integrally in engaged manner are automatically disengaged from one another. 
     The elastic strips  222   a ˜ 222   d  are moved through the guiding case  210 , with their top ends integrally combined by means of the frame  215 . Accordingly, the connecting pieces  240   a  and  240   b  come into mutual engagement always at fixed positions, wherein the guiding grooves  218  are positioned protrudently in comparison to the guiding grooves  216  up to the position where the grooves  228   a  and  228   b  of the connecting pieces  240   a  are positioned, so that the elastic strips  222   a  and  222   b  with the connecting pieces  240   b  may be appropriately fitted in the corresponding opposite grooves  228   a  and  228   b  of the connecting pieces  240   a  on elastic strips  222   c  and  222   d . Further, because the connecting pieces  240   a  are formed longer than and at a spacing from the grooves  216  and the connecting pieces  240   b  are shorter than the grooves  218  on the same elastic strips, the elastic strips  222   a ˜ 222   d  can travel smoothly without interference under the guidance of guiding grooves  216  and  218  formed on the guiding case  210 . 
     On the loading box  20  of a vehicle  10 , there are disposed rotatable winding drums  300   a ˜ 300   d  for winding elastic strips  222   a ˜ 222   d  in a roll form from the bottom of the strip column  220 , at the positions corresponding to the respective elastic strips  222   a ˜ 222   d  in the supporting leg  200 . As the winding drums  300   a ˜ 300   d  are all the same in the construction, the winding drum  300   b , for example, as a representative in FIG. 1 is explained by referring to FIG.  6 . 
     FIG. 6 shows the perspective view illustrating the appearance of a winding drum shown in FIG. 1, wherein the winding drum  300   b  comprises two discs  302   b  each having an axial hole  304   b , which discs are connected integrally by connecting members  306   b  arranged concentrically, an elastic strip  222   b  being wound around the connecting members. The winding drums  300   a ˜ 300   d  are rotated by driving shafts received in the axial holes  304   b  and supported by bearings provided on the loading box  20 . The size of the winding drums  300   a ˜ 300   d  is determined depending on the length of elastic metal strips  222   a ˜ 222   d . The winding drums  300   a ˜ 300   d  constructed as described above have winding force to keep the elastic strips wound in a roll form and their diameter is large enough to take care of the bending strength of the elastic strips. Therefore, the elastic strips  222   a ˜ 222   d  attached with connecting pieces  240   a  and  240   b  can be wound around the winding drums without problem. The functions of keeping the elastic strips wound on the drums and imparting winding force are performed by the first driving apparatuses  400 , which will be explained in more detail in the following. 
     The first driving apparatus  400  comprises a reversible driving motor  410  and is disposed on the loading box  20  in the vicinity of the moving supporting leg  200  to be in rotatable connection to any one winding drum  300   a  through a shaft  420 , so that the driving motor  410  may transmit to the winding drums  300   a ˜ 300   d  the driving force as required to wind the elastic strips  220   a ˜ 220   d  from the supporting leg  200  by first transmitting the driving force to the winding drum  300   a . The first driving apparatus  400  which is turned on or off by a power controller  600  causes to drive the winding drums  300   a ˜ 300   d  to wind the elastic strips  222   a ˜ 222   d , when the rectangular column  220  of the support leg  200  falls from an imaginary position indicated in FIG. 1 to a position indicated by a solid line, at which position, a fully lowered position, the winding drums  300   a ˜ 300   d  with rolls of elastic strips are caused to wind the elastic strips  222   a ˜ 222   d  with their remaining momentum. As those driving motors  410 , conventional ones may be used and so their explanation is not made. The first driving apparatuses  400  may be installed for each of the winding drums, but the driving force may be given to only one drum, because the elastic strips  222   a ˜ 222   d  winding around the drums  300   a ˜ 300   d  have an integrally united structure by the frame  215 . Therefore, the apparatus can be installed for only one winding drum for cost reduction or simple construction, when a reserve is not considered. While the first driving apparatus  400  as mounted to the winding drum  300   a  was explained as an example, the apparatus may be mounted to another drum beside the winding drum  300   a.    
     Regarding the moving supporting leg  200 , the moving up and down, or stop of the rectangular column  220  are realized by the second driving apparatus  800  which is installed separately from the first driving apparatus  400  and controlled by another controller  600 . The second driving apparatus  800  comprises a reversible driving motor  810  located at one side of the supporting leg  200  on the loading box of a vehicle  10 . 
     The driving shaft  812  of the reversible driving motor  810  is connected to the ratchet gear  830  rotatably mounted in the ratchet gear box  820  which is formed, with the side toward the column  220  open, at the top middle position of a side wall, or the right side wall  211   b  of the guiding case  210  in FIGS. 3 and 4, so that the ratchet gear  830  can be meshed in the chain  840  provided over the full height of an elastic strip  222   b  composing the column  220 . Accordingly, the driving force generated by the driving motor  810  and transmitted to the ratchet gear  830  through the driving shaft  812  causes the ratchet gear  830  to rotate and the resulting rotating force of the ratchet gear is transmitted to the chain  840  in mesh with the gear to thereby cause the movement of the column body  220  upward to the imaginary line position or down to the solid line position in FIG.  1 . While depending on the normal or reverse rotation of the driving motor  810 , the column  220  of the supporting leg  200  is accordingly moved up to the imaginary line position or down to the solid line position, the first driving motor  410  is brought to an inactive state in which no power is transmitted to winding drums  300   a ˜ 300   d  to allow the winding drums to rotate freely, when the second driving motor  810  causes the elevation of the rectangular column  220  to the imaginary line position in FIG. 1 by rotating normally, for example. Therefore, the elastic strips  222   a ˜ 222   d  can be easily unwound from the freely rotating drums  300   a ˜ 300   d  to be fed into the inside of the guiding case  210  so as to form the column  220  capable of reaching a high location. 
     In contrast, in the case of moving the rectangular column  220  down to the lower position from the imaginary high position through the reverse rotation of the second driving motor  810 , the first driving motor  410  is driven together with the second driving motor  810 , differently from the foregoing example, to cause the elastic strips  222   a ˜ 222   d  to be wound on the corresponding winding drums  300   a ˜ 300   d . Further, when the rectangular column  220  of a moving supporting body  200  positioned at a certain elevation over the guiding case  210  as shown in FIG. 1 or  4  is desired to maintain the stopping state, the second driving motor  800  is stopped or switched off to keep the ratchet gear  830  meshed in the chain  840 . Preferably the first driving apparatus  400  is also ceased in operation temporarily to maintain the winding state of the elastic strips on the winding drums  300   a ˜ 300   d . The on/off control of the first and second driving apparatuses  400  and  800  performed by the controller  600  is explained further in the following. The second driving apparatus  800  as installed for the specific elastic strip  220   b  was described in the above example but it may be installed in conjunction with one of other elastic strips. 
     The controller  600  for the driving apparatuses  400  and  800  may be preferably installed in the driver&#39;s compartment of a vehicle for the convenience of operation but it may be installed on the side of the loading box  20  outside the vehicle as the case may be. The controller  600  comprises a control box  620  having operation buttons  622 , which allow selective on/off operation of one or both of the driving apparatuses  400  and  800 , by constructing an electric circuit of a power supplying battery  610  connected with the first and second driving apparatuses  400  and  800 . The operation of any one button  622  on the control box  620  leads to the state of applying power to the first and second driving apparatuses  400  and  800 , the state of causing the activation of only the first driving apparatus  400 , the state of causing the activation of only the second driving apparatus  800 , or the state of causing the activation of both the first and second driving apparatus  400  and  800 . Such a construction is however a known art and so not described further. While a battery  610  already mounted in a vehicle was described in the foregoing example, a separate battery can be used. 
     Further, while the lifting apparatus for working at an elevated location  100 , which is installed on a vehicle for the purpose of mobility and convenience, was described in the above, the apparatus may be installed on any transporting means beside the car, if only it is mobile. 
     FIG. 7 shows another embodiment of the first driving apparatus employed in a lifting apparatus for high-place working according to the invention. 
     The present embodiment is intended to directly drive the elastic strips  222   a ˜ 222   d  by causing the winding drums  300   a ˜ 300   d  to rotate through driving shafts  530   a ˜ 530   d  and bevel gears  542 ,  546 ,  544  powered by the means of the driving force transmitted from the driving motor  510 , wherein the driving shafts  530   a ˜ 530   d  integrally provided on the respective winding drums  300   a ˜ 300   d  are integrally interconnected through bevel gears  542 ,  546 ,  544  and a sprocket wheel  514  provided on a driving shaft  530   a  is connected to a sprocket wheel  512  provided on the driving shaft  520  of the driving motor  510  through a transmission chain  516 , so that a driving apparatus  500  results, contrary to the above-described case wherein only a certain single winding drum  300   a  is driven by the first driving apparatus  400  to move elastic strips  222   a ˜ 222   d.    
     While such a driving apparatus  500  is complicated in construction compared to the driving apparatus  400 , a bigger driving force can be imposed on the rotation of the winding drums  300   a ˜ 300   d . On the other hand, the construction of the first driving apparatuses as mentioned above is not restricted to that embodiment, but a variety of modifications may be allowable as long as the construction can influence the driving force for the winding drums. 
     FIG. 8 shows the front view of a combination of plural lifting apparatuses with a high-place working stand according to still other embodiment of the invention and FIG. 9 shows the plan view of FIG.  9 . 
     The lifting apparatus for high-place working  100   a  according to this embodiment comprises a plurality of respective moving supporting legs  200   a ,  200   b  according to the first embodiment, arranged parallel to each other, for supporting a single working stand  700   a . That is, in the lifting apparatus  100   a , the first driving apparatus  400   a  functions such that the driving force produced from the first driving motor  410   a  is transmitted to all the winding drums  310   a ˜ 310   d ;  320   a ˜ 320   d  of the moving supporting legs  200   a  and  200   b , by extending the driving shaft  420   a  of the first driving motor  410   a  to be coaxial with two winding drums  310   a  and  320   a . Similarly, in the lifting apparatus  100   a , the second driving motor  810   a  of the second driving apparatus  800   a  has its driving shaft  812   a  extended long up to guiding cases  210   a  and  210   b  for connection to the respective ratchet gears  830   a  and  830   b  in meshed engagement with the chains  840   a  and  840   b  which are respectively installed on one side of the rectangular columns  230   a  and  230   b  (Refer to FIGS.  8  and  9 ). Therefore, the second driving motor  810   a  can cause the simultaneous travel of the rectangular column  230   a  and  230   b  of the moving supporting legs  200   a  and  200   b . This two-leg construction provides a solider and stabler support than the single moving supporting leg  200  in the foregoing embodiments. The rest construction and functions in the present embodiment are substantially the same as afore-mentioned embodiments and so concrete descriptions are not made. 
     As described above, an arbitrary high-elevation is accessible according to the present invention, because the elastic strips unwound from winding drums are caused continuously to form a supporting leg of rectangular form. 
     It is to be understood that, while the invention was described mainly with respect to specific embodiments, the invention is never restricted to those embodiments and a variety of modifications and alterations would be possible to a man skilled in the art by referring to the description or drawings presented here and within the spirit of the invention and thus those modifications or alterations are to fall within the scope of the invention, which scope should be limited only by the attached claim.