Patent Publication Number: US-2012027559-A1

Title: Tool and method for lifting and dragging heavy loads

Description:
TECHNICAL FIELD 
     This description relates to the field of hand-operated tools. More particularly, this description relates to manual tools for handling heavy loads. 
     BACKGROUND OF THE INVENTION 
     The prior art discloses tools and methods for lifting and dragging heavy loads such as manhole covers or the like for which the user must bent down during its operation. In other tools and methods, the user is stand up, but must adopt poor ergonomic positions. An ergonomic position aims to keep the back of the user substantially straight and vertical and to keep the forearms substantially horizontal, or slightly below horizontal, while keeping both hands at the same level. Furthermore, there is a need for a tool comprising a safety base for gripping the surface to avoid slippage and to prevent an incorrect movement or a wrong posture of the user. 
     SUMMARY OF THE INVENTION 
     According to an aspect of the invention, there is provided a user-operated tool for lifting and dragging a heavy load on a surface. The tool comprises an elongated body having an upper end, a lower end, and a flex point located between the upper end and the lower end. The lower end is for making contact with the surface in the vicinity of the heavy load. The upper end comprises a right grip and a left grip disposed on the elongated body. The tool further comprises a lift and drag member connected to the elongated body. The lift and drag member is movable about the flex point. The lift and drag member comprises a hook member for hooking to the heavy load. In use, the user grips the left and right grips with his left and right hands respectively, his hands being at an equal distance from the surface, while keeping his forearms substantially horizontal and his back straight and substantially vertical. The user rotates the elongated member around the lower end and away from the heavy load. The lift and drag member thereby first lifts and then drags the heavy load toward the lower end. 
     According to another aspect of the invention, there is provided an ergonomic method for lifting and dragging a heavy load on a surface by a user. The method comprises: providing a hand-operated tool having a lower end and an upper end, the upper end comprising a left grip and a right grip; resting the lower end on the surface in the vicinity of the heavy load; hooking the hook member to the heavy load; positioning the hand-operated tool such that the user, with his back straight and substantially vertical, can grip the left and right grips with his left and right hands respectively, his hands being at an equal distance from the surface, while keeping his forearms substantially horizontal; gripping the left and right grips with his left and right hands respectively; and rotating the elongated member around the lower end and away from the heavy load, thereby first lifting and then dragging the heavy load on the surface. 
     According to another aspect of the invention, there is provided a user-operated tool for lifting and dragging a heavy load on a surface. The tool comprises an elongated body having an upper end, a lower end, and a flex point located between the upper end and the lower end. The upper end comprises a grip disposed on the elongated body. The tool further comprises a sole pivotally coupled to the lower end, the sole comprising a first gripping portion and a second gripping portion. The first gripping portion is for making contact with the surface and is adapted to grip a type of surface and the second gripping portion is for making contact with the surface and is adapted to grip another type of surface. The tool further comprises a lift and drag member connected to the elongated body. The lift and drag member is movable about the flex point. The lift and drag member comprise a hook member for hooking to the heavy load. In use, the user selects one of the first gripping portion and the second gripping portion for making contact with the surface by rotation of the sole with respect to the elongated body, then the user grips the grip with at least one of his hands and the user rotates the elongated body around the sole and away from the heavy load. The lift and drag member thereby first lifts and then drags the heavy load toward the sole. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features and advantages of the present invention will become apparent from the following detailed description, taken in combination with the appended drawings, in which: 
         FIG. 1  is a perspective view illustrating a tool, in accordance with an embodiment of the invention; 
         FIG. 2  is an exploded view of the tool of  FIG. 1 ; 
         FIG. 3   a  is top view of the tool of  FIG. 1 ; 
         FIG. 3   b  is a front elevation of the tool of  FIG. 1 ; 
         FIG. 3   c  is a side elevation of the tool of  FIG. 1 ; 
         FIG. 4   a  is a side elevation of the tool of  FIG. 1  in use before lifting a heavy load and gripped by a normal user; 
         FIG. 4   b  is a side elevation of the tool of  FIG. 1  in use before lifting an heavy load and gripped by a small user; 
         FIG. 4   c  is a side elevation of the tool of  FIG. 1  in use before lifting an heavy load and gripped by a tall user; 
         FIG. 5  is a side elevation of the tool of  FIG. 1  in use after lifting and dragging the heavy load and gripped by the tall user; 
         FIG. 6  is a flowchart showing a method for lifting and dragging a heavy load according to an embodiment of the invention; 
         FIG. 7   a  and  FIG. 7   b  are detailed perspective views of the lower end of the tool according to another embodiment of the invention; and 
         FIG. 8  is a perspective view illustrating a tool, in accordance with another embodiment of the invention; 
     
    
    
     It will be noted that throughout the appended drawings, like features are identified by like reference numerals. 
     DETAILED DESCRIPTION 
     Referring now to the drawings, and more particularly to  FIGS. 1 ,  2  and  3   a - b - c , there is shown a tool  100  according to an embodiment of the invention. The tool  100  is mainly made of an elongated body  101  and a lift and drag member  160 . The elongated body  101  comprises an upper end  103  and a lower end  104 , the lower end  104  for making contact with a surface, not shown. The upper end  103  comprises a right grip e.g.  137   b  and a left grip e.g.  137   a , forming a grip, not numbered, for manipulating the tool  100 . The lift and drag member  160  is connected to the elongated body  101  at a flex point  161  located between the upper end  103  and the lower end  104 . The lift and drag member  160 , movable about the flex point  161 , comprises a hook member  144  for hooking to a heavy load, not shown, such as manhole covers or the like. 
     The upper end  103  and the lower end  104  are firmly connected by a tube  102  offering a fold resistance. In the lower part of the elongated body  101 , the tube  102  is arched according to two plans. In a first plan, shown on  FIG. 3   b , the tube  102  is arched for projecting a longitudinal axis  163  of the upper part of the elongated body  101  to the middle of the sole  105 , thereby freeing a space for receiving a foot of a user in the longitudinal axis  163 . In a second plan, shown on  FIG. 3   c , the tube  102  is arched for taking the projection of the flex point  161  according the longitudinal axis  163  away from the sole  105 . A person skilled in the art will understand that the tube  102  can be replaced by another beam having a portion made of metal bar, truss, plastic, composite material, wood or the like and replace such arched beam by a straight beam or by a beam differently arched. 
     At the lower end  104 , a shaft  110  perpendicularly crosses the tube  102  and is fixed longitudinally to the tube  102  with a nut  116  screwed on one end of the shaft  110 . The nut  116  interfaces with the tube  102  by washers  114 - 115 . A cap  117  is screwed in the shaft  110  by a screw  118  for hiding the nut  116 . The shaft  110  is rotationally fixed to the tube  102  by a screw  111 , screwed in the tube  102  and pressing against the shaft  110 . A ground part  109  and a foot part  106  are screwed together by screws  113   a - b - c - d  around the shaft  110  forming a sole  105 . The sole  105  is free to rotate around the shaft  110 . The ground part  109 , being for making contact with the surface, has an external grooved first gripping face  165  for preventing the sole  105  from slipping on the surface. The foot part  106  being for receiving a foot of the user has a second gripping face  166  for preventing the foot from slipping. A person skilled in the art could easily replace the rotatable sole  105  by a fixed sole, a peg lightly drivable through the surface or a sole as described on  FIGS. 7   a  and  7   b.    
     At the other end of the shaft  110 , a peg  108  is inserted in the shaft  110  and blocked by a screw  112  screwed in the shaft  110  and pressing against the peg  108 . The peg  108  is notably used for cleaning a receptacle of the heavy load thereby making easier the further lifting of the heavy load. A person skilled in the art could easily replace the peg  108  by another peg tool, e.g., a pick or a blade, or by a cleaning tool, e.g., a brush or by a locking-unlocking tool thus permitting to lock and unlock the heavy load in the receptacle or by any other useful tool. A person skilled in the art could also easily set a peg tool, a cleaning tool, a locking-unlocking tool or any other useful tool at another appropriated location on the tool  100 . 
     The upper end  103  comprises a right handle  162   b  and a left handle  162   a , each U-shaped and symmetrically disposed, by its two ends, on the elongated body  101 . Each handle has an upper grip  135   a - b , a lower grip  136   a - b  and a middle grip  137   a - b . Circulating continuously along each handle  162   a - b  between the upper grip  135   a - b  and the lower grip  136   a - b , at any location, can be defined a right grip and a left grip fitted to the size of the user. Other embodiments for the right handle  162   b  and the left handle  162   a  are discussed below. 
     According to another embodiment, not shown, the upper end  103  comprises a right handle and a left handle connected to the elongated body  101  offering a plurality of right grips and left grips at a plurality of distances from the lower end  104 . 
     Another embodiment, not shown, could comprise a right handle and a left handle connected to the elongated body  101 , each handle having a plurality of branches, each right branch and left branch respectively having a right grip and a left grip. 
     Another embodiment, not shown, could comprise a right handle and a left handle connected to the elongated body  101 , each handle having respectively a right grip and a left grip, the right handle and the left handle having an adjustable position along the elongated body  101 , thus offering a right grip and a left grip whose the distance from the lower end  104  can vary. 
     Another embodiment, not shown, could comprise a right handle and a left handle connected to the elongated body  101  and made of rigid material, e.g. metal, plastic, composite, wood, etc., or flexible material, e.g. strap, chain, cable, string, wire, etc. It is understood that combinations of these previous embodiments are possible. 
     Returning now to the embodiment  100  of the invention shown on  FIGS. 1 ,  2  and  3   a - b - c , there is shown the lift and drag member  160  mainly made of a strap  138 . The strap  138  is connected to the elongated body  101  by a strap reel  119  and by a guide  164  defining the flex point  161 . The lift and drag member  160  can move about the flex point  161 . At the outer end of the strap  138 , the hook member  144  is attached via a ring  145  and a removable shackle  146  allowing the hook member  144  to pivot. A person skilled in the art could easily design several embodiments, not shown, of hook members fitted to the heavy load, such as a fitted hook, a versatile hook, a key, a fastener, a magnetic attachment or the like. Other embodiments for the lift and drag member  160  connected to the elongated body  101  are discussed below. 
     Another embodiment, not shown, comprises a lift and drag member having a portion made of tube, metal bar, truss, plastic, composite material, wood, chain, cable, string, wire or the like. 
     Another embodiment, not shown, comprises a lift and drag member having a length adapter for varying the length of the lift and drag member and thereby adapting the tool according to the heavy load and the surface. In this embodiment, the length adapter includes a continuous adapter by screwing, by sliding with continuous stopper or by winding or could be a discontinuous adapter by fastening at specific locations. 
     Another embodiment, not shown, comprises a pivoting means for pivoting the lift and drag member around the flex point, the pivoting means connected to the elongated body and comprising a pivot, a flexible material or the like. 
     Another embodiment, not shown, comprises a displacing means for displacing the pivoting means along the elongated body and thereby for displacing the flex point on the elongated body. The displacing means could comprise a continuous controller like a slide with a continuous stopper, a discontinuous controller like a fastener able to fasten at specific location on the elongated body or the like. 
     Returning now to the embodiment  100  of the invention on  FIG. 2 , there is detailed the strap reel  119  located below the upper end  103 . A lug  125  is welded to the tube  102  for receiving a U-shaped base  121  fixed to the lug  125  by screws  126   a - b  passing through the tube  102  and through the lug  125 . A wheel  120  and a united ratchet  123  are pivotally coupled to the U-shaped base  121  around a pivot  122 . The strap  138  is winded on the wheel  120 . A spiral spring  143  takes base on the U-shaped base  121  for biasing the strap  138  to wind around the wheel  120 . A lever  124  operates a dispensing mechanism, not shown. 
     The lever  124  has a stable position along the tube  102 . In this stable position, the dispensing mechanism blocks the wheel  120  preventing the strap  138  from winding on the wheel  120  and firmly preventing the strap  138  from unwinding from the wheel  120  using the ratchet  123 . The lever  124  has an unstable adjusting position when a user squeezes the handle  124  toward the tube  102 . Then, the end of the lever  124  enters in the tube  102  through a hole  142 . The adjusting position is an unstable position. That means that to maintain the adjusting position the user needs to maintain a pressure on the lever  124 . In this position, the strap  138  can be wound or unwound according to the need of the user. Thereby, the user can adjust the length of the strap  138  for operating the tool according to the heavy loads to be dragged, the environment and his liking. 
     Two parts of a cover  127 - 128  are screwed together around the strap reel  119  and around the tube  102  by screws  129   a - b - c - d - e - f . The cover  127 - 128  is for hiding the strap reel  119 , preventing user from injury and protecting the mechanism from excessive dust. On part  128  of the cover, there are a secondary handle  147  screwed on and a handle cover  130  screwed on the secondary handle  147  by screws  131   a - b . The secondary handle  147  is useful for transporting the tool between a storage location and a utilization location. For comfort purposes, the secondary handle  147  is located near the center of gravity of the tool. The secondary handle is particularly well oriented for using the peg  108 , one hand gripping the secondary handle  147 , the other hand gripping the left handle  162   a.    
     According to another embodiment, the above described mechanism can be replaced by another mechanism like an automotive belt which allows blocking the wheel by pulling a blow on the strap. Also, the strap reel  119  can be replaced by a fixed fastener for fixing the end of the strap  138  to the elongated body  101 , at a specific location or at several possible location for varying the length of the lift and drag member. 
     Returning now to the embodiment  100  of the invention on  FIG. 2 , there is detailed the guide  119  located between the upper end  103  and the lower end  103 . A U-shaped lug  132  bestrides the tube  102  and is fastened to the tube  102  by a fastener  134  passing through the U-shaped lug  132  and passing through the tube  102  by a hole  141 . Two rollers  133   a,b  are held by the U-shaped lug  132  and can roll for guiding the strap  138  passing between the two rollers  133   a,b . The two rollers  133   a,b  and the U-shaped lug  132  form a guiding means which fixes the distance of the strap  138  to the elongated body  101  at a point where the rollers  133   a,b  are located. The guiding means forces the strap  138  to flex in a given location, thereby defining a flex point. A displacing means allows the guiding means to displace along the elongated member  101  thereby displacing the flex point on the elongated body  101 . The displacing means allows two positions along the elongated body  101 , one at the hole  141 , another at hole  140 . 
     Now referring to  FIG. 4   a , there is shown the tool  100  in a use position. The sole  105  is rested on the surface  150  in the vicinity of the manhole cover  149 . A normal user steps on the sole  105  with his foot  153 . Thereby the sole  105  is pressed on the surface  150 , thus creating a fulcrum with respect to the surface for the tool  100  and thus reinforcing the immobilization of the fulcrum and offering it to the user. 
     The hook member  144  is hooked to a hook point  148  of the manhole cover  149 . The elongated body  101  is raised and, using the lever  124 , the length of the strap  138  is adjusted for being fairly tense. The level of the guide  164  is previously fixed with the fastener  134 . 
     The normal user chooses a right grip and a left grip, both at the same distance from the surface  150 , adapted such that when the user grips the left grip  137   a  and right grip, not shown, with his left hand  151  and right hand, not shown, respectively, his hands  151  are at an equal distance from the surface  150 , while keeping his forearms  152  substantially horizontal and his back straight and substantially vertical. In this case the left grip  137   a  is located on the vertical portion of the left handle  162   a.    
     Now referring to  FIG. 4   b , there is shown the tool  100  in the same configuration as on  FIG. 4   a . A small user replaces the normal user. The small user chooses a right grip and a left grip, both at the same distance from the surface  150 , adapted such that when the user grips the left grip  136   a  and right grip, not shown, with his left hand  154  and right hand, not shown, respectively, his hands  154  are at an equal distance from the surface  150 , while keeping his forearms  155  substantially horizontal and his back straight and substantially vertical. In this case the left grip  136   a  is located on the lower portion of the left handle  162   a.    
     Now referring to  FIG. 4   c , there is shown the tool  100  in the same configuration than on  FIG. 4   a . A tall user replaces the normal user. The tall user chooses a right grip and a left grip, both at the same distance from the surface  150 , adapted such that when the user grips the left grip  135   a  and right grip, not shown, with his left hand  157  and right hand, not shown, respectively, his hands  157  are at an equal distance from the surface  150 , while keeping his forearms  158  substantially horizontal and his back straight and substantially vertical In this case, the left grip is located on the upper portion of the left handle  162   a.    
     Now referring to  FIG. 5 , there is shown the tool  100  used by the tall user. The tall user has already pulled on the left grip  135   a  and the right grip, not shown, toward him and thus rotated the elongated body including the tube  102  around the lower end including the sole  105  and away from the heavy load  149 , the lift and drag member  160  thereby first lifts and then drags the heavy load  149  toward the lower end including the sole  105 . To drag the cover  149  off the manhole, the tall user has to release his foot  159  from the sole  105 , move the sole  105  away from the manhole cover  149 , squeezing the handle  124  to the tube  102  for extending the strap  138 , step again on the sole  105  and pull again on the left grip  135   a  and the right grip. 
     Now referring to  FIG. 6 , there is shown a flowchart of a method  600  for lifting and dragging a heavy load according to an embodiment of the invention. Method  600  comprises: providing a hand-operated tool having a lower end and an upper end (step  602 ), the upper end comprising a left grip and a right grip; resting the lower end on the surface in the vicinity of the heavy load (step  604 ); hooking the hook member to the heavy load (step  606 ); positioning the hand-operated tool such that the user, with his back straight and substantially vertical, can grip the left and right grips with his left and right hands respectively, his hands being at an equal distance from the surface, while keeping his forearms substantially horizontal (step  608 ); gripping the left and right grips with his left and right hands respectively (step  610 ); and rotating the elongated member around the lower end and away from the heavy load, thereby first lifting and then dragging the heavy load on the surface (step  612 ). 
     In the method  600 , wherein the lower end optionally comprises a sole having a first gripping portion and a second gripping portion, the sole is optionally pivotally coupled to the hand-operated tool. Optionally, the method  600  further comprises selecting one of the first gripping portion and the second gripping portion for making contact with the surface by rotation of the sole with respect to the hand-operated tool, not shown. 
     Optionally, the method  600 , wherein the sole optionally further having a foot portion, further comprises applying a force on the foot portion by a user&#39;s foot, for transmitting a portion of the force to the selected of the first gripping portion and the second gripping portion toward the surface for gripping the surface, not shown. 
     Now referring to  FIG. 7   a  and  FIG. 7   b , there is shown a sole  700  according to another embodiment of the invention having two positions in use. The sole  700  is pivotally coupled to a shaft  701 . The shaft is an extension of the tool. The sole  700  comprises a first gripping portion  702  for making contact to a surface, not shown. The first gripping portion  702  comprises a plurality of pegs  703  protruding outwardly from the first gripping portion  702  being thus adapted for gripping a type of surface such as ice or snow. On the opposite side, the sole  700  further comprises a second gripping portion  704  for making contact to another surface, not shown. The second gripping portion  704  comprises a rubber grooved plate  705 , namely an anti-slipping plate, making the second gripping portion  704  adapted for gripping another type of surface such as concrete, bitumen or cast steel without damaging the surface. The rotation of the sole  700  makes possible the designing of large areas for making contact with surfaces that decreases a chance the sole slips with respect to the surface. 
     The sole  700  further comprises a first foot portion  706  and a second foot portion  707  opposite the first foot portion  706 . Referring to  FIG. 7   a , there is shown the sole  700  in a first position, the second gripping portion  704  being selected for making contact to a surface, not shown, and the first foot portion  706  being located on the top of the sole  700  for interfacing with a user&#39;s foot applying a first force on the first foot portion  706  and for transmitting a portion of the first force to the second gripping portion  704  toward the surface. 
     Referring to  FIG. 7   b , there is shown the sole  700  in a second position, the first gripping portion  702  being selected for making contact to a surface, not shown, and the second foot portion  707  being located on the top of the sole  700  for interfacing with a user&#39;s foot applying a first force on the second foot portion  707  and for transmitting a portion of the first force to the first gripping portion  702  toward the surface. 
     A tool having such a sole  700 , offering a large and adapted area for making contact with a surface and permitting to apply a force toward the surface, makes it more comfortable and more secure for a user. It is understood that a person skilled in the art could easily replace the pegs  703  or the rubber grooved plate  705  with others components such as notched sheet metal. 
     Now referring to  FIG. 8 , there is shown a tool  800  for lifting and dragging a heavy load on a surface, not shown. The tool  800  comprises an elongated body  801  having an upper end  802 , a lower end  803 , and a flex point  804  located between the upper end  802  and the lower end  803 . The upper end  802  comprises a grip  805  disposed on the elongated body  801 . The tool  800  further comprises a sole  806  pivotally coupled to the lower end  803 . 
     The sole  806  comprises a first gripping portion  807  and a second gripping portion  808 , the first gripping portion  807  being for making contact with the surface and adapted to grip a type of surface and the second gripping portion  808  being for making contact with the surface and adapted to grip another type of surface. The first gripping portion  807  comprises a rubber plate  809 , namely an anti-slipping plate, making the first gripping portion  807  adapted for gripping a type of surface such as concrete, bitumen or cast steel without damaging the surface. At the opposite according to the axis  811 , the second gripping portion  808  comprises a plurality of pegs  810  protruded outwardly from the second gripping portion  808  being thus adapted for gripping a type of surface such as ice or snow. The rotation of the sole  806  makes possible a designing of large areas for making contact with surfaces that decreases a chance the sole slips with respect to the surface. 
     The tool  800  further comprises a lift and drag member  812  connected to the elongated body  801 , the lift and drag member  812  being movable about the flex point  804 , the lift and drag member  812  comprising a hook member  813  for hooking to the heavy load. 
     In use, the user selects one of the first gripping portion  807  and the second gripping portion  808  for making contact with the surface by rotation of the sole  806  with respect to the elongated body  80 . The user applies a force on the non selected one of the first gripping portion  807  and the second gripping portion  808  with a foot, for transmitting a portion of the force to the selected of the first gripping portion  807  and the second gripping portion  808  toward the surface for gripping the surface. Then, the user grips the grip  805  with at least one of his hands, the user rotates the elongated body  801  around the sole  806  and away from the heavy load, the lift and drag member  812  thereby first lifts and then drags the heavy load toward the sole  806 . 
     While preferred embodiments of the invention have been described above and illustrated in the accompanying drawings, it will be evident to those skilled in the art that modifications may be made therein without departing from the essence of this invention. Such modifications are considered as possible variants comprised in the scope of the invention.