Abstract:
The frame of a large heavy duty ratchet supports a spool about an axis of rotation. A handle, pivotable about the axis of rotation, includes protrusions engageable with toothed wheels on opposed sides of the spool to urge incremental rotation of the spool upon repetitive pivotal movement of the handle. A pair of spring-loaded pawls engage the toothed wheels to limit the direction of rotation of the toothed wheels. A cam, formed as part of the handle, disengages the pair of pawls from the toothed wheels upon pivotal movement of the handle to a certain extent to permit rotation of the spool in either direction.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application is a continuation of an application entitled “LARGE HEAVY DUTY RATCHET”, Ser. No. 13/935,241, filed Jul. 3, 2013, which claims priority to the disclosure contained in a provisional patent application entitled “HEAVY DUTY RATCHET”, assigned Ser. No. 61/667,580 and filed Jul. 3, 2012, which describes an invention made by the present inventor. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to ratchets and, more particularly, to multiple purpose large heavy duty ratchets. 
         [0004]    2. Description of Related Prior Art 
         [0005]    Ratchets for applying tension to a cord have been in use for many years and numerous patents have issued directed thereto. U.S. Pat. Nos. 6,068,242, 6,092,791, and Des.362,614 are representative and are incorporated herein by reference. These ratchets generally include a pair of discs supporting an ingoing and outgoing cord. Upon exerting a pulling force on the outgoing cord, tension is applied to the ingoing cord. To prevent slippage of the cord extending about the pair of discs, there are ridges on the pair of discs in frictional engagement with the cord. Reverse rotation of the pair of discs is generally precluded by use of a pawl engaging a toothed wheel or gear. Upon manual release of the pawl, the pair of discs are free to rotate in either direction. Usually, a hook extends from the body of the ratchet for engagement with an anchor or the like. 
         [0006]    Ratchets used to apply tension to webbing have also been available for many years. These ratchets include a spool having a slot formed therein to receive the end of a length of webbing. A pivotally mounted handle includes a spring-loaded slide for engagement with sprockets disposed on either side of the spool. Upon rotation of the handle, the spool rotates and webbing becomes drawn about the spool. Movement of the spool in the opposite direction to release tension on webbing is restricted by a further slide engaging the sprockets. Upon manual engagement of the further slide to withdraw it from engagement with the sprockets, the spool is free to rotate to permit unwinding of the webbing. 
         [0007]    Either type of ratchet described above is useable to apply loads usually not in excess of 100 pounds. Moreover, the mechanism of release of the spool requires a certain degree of manual dexterity and strength as a function of the load imposed on the cord or webbing. Thus, these ratchets have limited use with respect to the tension load capability. Furthermore, a significant degree of manual strength may be required to release the spool to permit unwinding of the cord or webbing. 
       SUMMARY OF THE INVENTION 
       [0008]    The present invention is directed to ratchet mechanisms capable of providing tension loads to a rope, strap or webbing in excess of 40,000 pounds. Loads of this magnitude require not only robust construction but also mechanisms easily manually useable. A two-sided frame is joined at one end to support a hook for engagement with either an anchor or the load. The open end of the frame rotatably supports a spool about an axis of rotation. Toothed wheels on either side of the spool are mechanically locked with the spool. A handle is pivotable about the axis of rotation of the spool and includes a pivotable member for engaging the teeth of the toothed wheels to cause rotation in one direction of the toothed wheels and the spool as the handle is pivoted about the axis of rotation. A pair of spring-loaded pawls engage respective toothed wheels to prevent rotation in the other direction. Upon rotation of the handle in the one direction a certain distance, a cam engages a bar extending between the pawls to disengage the pawls from the toothed wheels. Thereafter, the spool is free to rotate in either direction and the cord or webbing may be unwound from about the spool. The end of the cord or webbing may include a hook or other device for attachment to either an anchor or the load. 
         [0009]    It is therefore a primary object of the present invention to provide a ratchet capable of handling a load of tens of thousands of pounds. 
         [0010]    Another object of the present invention is to provide a large scale ratchet having an operating handle capable of grasping by a user&#39;s hand. 
         [0011]    Yet another object of the present invention is to provide a ratchet having a cam useable to release an applied load. 
         [0012]    Still another object of the present invention is to provide a ratchet having interchangeable spools for engaging a rope, a strap, webbing or dual webbings. 
         [0013]    A further object of the present invention is to provide a ratchet with a hollow spool having an axially oriented passageway in engagement with a laterally oriented passageway to accommodate insertion of the end of a rope through the lateral passageway and drawing it out through the axial passageway. 
         [0014]    A yet further object of the present invention is to provide a manually operable ratchet capable of exerting a load on a rope or webbing extending therefrom on the order of tens of thousands of pounds. 
         [0015]    A still further object of the present invention is to provide a method for using a ratchet to apply a load of tens of thousands of pounds. 
         [0016]    A still further object of the present invention is to provide a method for using a ratchet with any of several different types of spools. 
         [0017]    These and other objects of the present invention will become apparent to those skilled in the art as the description thereof proceeds. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    The present invention will be described with greater specificity and clarity with reference to the following drawings, in which: 
           [0019]      FIG. 1  is an isometric view of a large heavy duty ratchet; 
           [0020]      FIG. 2  is a cutaway view taken along lines  2 - 2  as shown in  FIG. 1 ; 
           [0021]      FIG. 3  is a partial cutaway view showing movement of the handle; 
           [0022]      FIG. 4  is a partial cutaway view illustrating disengagement between the handle and the spool supported toothed wheel and between the spool supported wheel and the pawl; 
           [0023]      FIG. 5  is a partial cross-sectional view taken along lines  5 - 5  as shown in  FIG. 4 ; 
           [0024]      FIG. 6  is a partial side view taken along lines  6 - 6  as shown in  FIG. 5 ; 
           [0025]      FIG. 7  is a partial cutaway view illustrating disengagement of the pawls from the toothed wheels attendant the spool; 
           [0026]      FIG. 8  is a top view taken along lines  8 - 8  as shown in  FIG. 7 ; 
           [0027]      FIG. 9  is an exploded view showing parts of the ratchet; 
           [0028]      FIG. 10  is an isometric view of the ratchet embodying a first variant spool; 
           [0029]      FIG. 11  is an isometric view of the first variant spool; 
           [0030]      FIG. 12  is an isometric view of a second variant spool; 
           [0031]      FIG. 13  is an exploded view of the second variant spool; 
           [0032]      FIG. 14  illustrates the engagement of a cord with the second variant spool; 
           [0033]      FIG. 15  illustrates a ramp useable with the second variant spool, as shown in  FIG. 14 ; and 
           [0034]      FIG. 16  illustrates a variant of the spool shown in  FIGS. 1 and 2 . 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0035]    Referring to  FIG. 1 , there is shown a ratchet  10  particularly adapted to handle loads in excess of 40,000 pounds. To handle such loads, the components of the ratchet are made of high strength materials and are preferably composite or metallic. The ratchet includes a pair of frames  12 ,  14  defining a hook  16  at one end. As illustrated, an insert  18  is disposed between the ends of frames  12 ,  14  defining hook  16 . These three elements may be joined with one another by nut and bolt sets  20 ,  22 . A spring-loaded keeper  24  may be used to prevent inadvertent disengagement of hook  16  from whatever element to which the hook is attached. It is to be understood that the hook may be engaged with an anchor or with an item or load to be drawn toward the anchor. In either event, the operation of ratchet  10  would not be changed. Frames  12  and  14  are bent at approximate the locations corresponding with lines  26 ,  26 ′ to locate ends  28 ,  30  spaced apart and parallel with one another. Toward the hook end, frames  12 ,  14  converge toward one another and are essentially parallel with one another in the area defined by hook  16 . A nut and bolt set  32  draws the frames toward one another to prevent splaying or distortion. 
         [0036]    Referring jointly to  FIGS. 1 and 2 , certain features will be described. Frame end  28 ,  30  include circular apertures, of which aperture  34  in frame end  28  is illustrated. A spool  36  is rotatably supported within these apertures to accommodate rotational movement of the spool relative to frames  12 ,  14 . The spool is essentially cylindrical and includes a slot  38  extending through the midpoint. The purpose of the slot is to capture the end of a strap or webbing by drawing an end of the strap or webbing through the slot and thereafter capturing the end by further webbing wrapped around the spool. 
         [0037]    A pair of toothed wheels  42 ,  44  are secured to spool  36  to prevent independent rotation therebetween. A handle  46  pivots about the axis of rotation of spool  36 . It includes a pair of protrusions  48 ,  50  for engagement with corresponding teeth  52 ,  54  of toothed wheels  42 ,  44 , respectively. Upon pivotal movement of handle  46 , as particularly shown in  FIG. 2 , the toothed wheels and attached spool  36  are caused to rotate in the counterclockwise direction, as illustrated in  FIG. 2 . Protrusions  48 ,  50  extend from a pivotable lever  56  pivotal about shaft  58  and spring-loaded by spring  60 . Guides  49 ,  51  ride along the underside of overhangs  53 ,  55  to urge engagement of the protrusions with the teeth of the toothed wheels. A pair of pawls  62 ,  64 , of which pawl  64  is shown in  FIG. 2 , engage the teeth of respective toothed wheels  42 ,  44  to preclude clockwise movement of the toothed wheels and the attached spool. A shaft  66  pivotally supports the pair of pawls. A spring  68  biases the pawls in the counterclockwise direction to engage the toothed wheels and prevent their rotation and that of the spool in the clockwise direction. Yet, the spring permits pivotal movement of the pawls clockwise as the teeth of the toothed wheels rotate counterclockwise therepast. 
         [0038]    Referring jointly to  FIGS. 3, 4, 5 and 6 , further operation of handle  46  will be described. Handle  46  includes two spaced apart planar fixtures  70 ,  72  (see also  FIG. 9 ) joined at one end by a bar  74 . The other end of each fixture includes an element  76  centrally apertured for receiving spool  36  rotatably mounted therein. The configuration of each element  76  includes a cam  78  to bear against shaft  80  interconnecting pawls  62 ,  64  as handle  46  is rotated in the counterclockwise direction shown in  FIGS. 3 and 4 . Because of the radial extension of the cam, it will tend to urge shaft  80  in a clockwise direction about shaft  66 . This movement is resisted by spring  68 . The cam may include an indentation  82  to capture shaft  80 . Upon engagement of cam  78  with shaft  80 , pawls  62 ,  64  will become disengaged from the respective toothed wheels, of which wheel  44  is shown in  FIGS. 3 and 4 . Additionally, the end of lever  56  is depressed against the force of spring  60  to result in movement of the lever in the direction indicated by arrows  84  shown in  FIG. 4 . The resulting pivotal movement of lever  56  will cause disengagement of its protrusions (of which protrusion  50  is shown). Thereby, protrusions  48 ,  50  become disengaged from the respective toothed wheels. Now, spool  36  is free to rotate in either direction. Thereby, the attached webbing may be drawn away from and disengaged with spool  36  as the spool can rotate to permit unwinding of the webbing thereabout. 
         [0039]    Referring briefly to  FIGS. 5 and 6 , further details attendant the use of cam  78  to disengage pawls  62 ,  64  from the toothed wheels will be described. Shaft  80  extends to the outside of each of pawls  62 ,  64 , as shown in  FIG. 6 . Indentation  82  of cam  78  receives shaft  80  and because of the indentation will retain the shaft therewithin until handle  46  is rotated clockwise (see  FIGS. 3 and 4 ). 
         [0040]    Referring jointly to  FIGS. 7 and 8 , the functional and physical relationships of the various elements will be described. The cutaway view of the ratchet shown in  FIG. 7  illustrates the ratchet in the configuration to permit free rotation of spool  36  in either direction. It also illustrates the end of pivotal movement of handle  46  wherein indentation  82  of cam  78  is in engagement with shaft  80  to rotate pawl  64  away from toothed wheel  44 . Protrusion  50  of lever  56  would normally be in engagement with one of the teeth of toothed wheel  44 , as shown in  FIG. 4 . However, for illustrative purposes the lever is shown in its quiescent position. The top view shown in  FIG. 8  illustrates ends  28 ,  30  of frames  12 ,  14  being essentially parallel with one another. As shown in  FIG. 8 , the tapering section of frames  12 ,  14  may include ledges  84 ,  86  to lend further robustness to the ratchet. 
         [0041]      FIG. 9  is an exploded view illustrating the primary elements of ratchet  10  and their relative locations. By inspection, it becomes apparent how these elements interact and cooperate with one another. As shown, spool  36  includes diametric slots at opposed ends of which slot  90  is shown. Each of these slots includes a central expanded keyway  92 . An insert  94  is placed within the slot  90  and includes a key  96  cooperating with keyway  92 . Toothed wheel  44  includes a central bar  98  for placement within slot  90  of the spool and a key  100  for engaging keyway  92 . Thereby, toothed wheel  94  is in locking engagement with spool  36 . A further insert  94  is disposed within a slot on the other end of spool  36 , which is similar to slot  90 . It also includes a keyway similar to keyway  92  for receiving key  96 . Toothed wheel  42  includes a central bar  100  for engagement with the spool  36  and a key  102  for engaging the keyway in the slot. A snap ring  104  engages a groove  106  in spool  36 , which groove is external of fixture  72 . A further snap ring  108  engages a groove  110  in the other end of spool  36 , which groove is exterior of fixture  70 . Thereby, the toothed wheels are in non-rotatable engagement with the spool and the spool is captured intermediate fixtures  70 ,  72 . 
         [0042]    Referring jointly to  FIGS. 10 and 11 , there is shown a further embodiment of the present invention. In particular, a ratchet  10  is shown with a first variant spool  120 . This spool includes laterally disposed toothed wheels  120 ,  124 , as described above. Spool  120  includes a pair of discs  126 ,  128 . These discs are mechanically joined with one another to preclude independent rotation therebetween. Each of these discs includes non-radial ridges  129  with the ridges of one disc being interleaved with the ridges of the other disc. Further details of these discs are set forth in U.S. Pat. Nos. 6,068,242, 6,092,791, and Des.362,614, recited above and incorporated herein by reference. The function and purpose of the discs and the ridges disposed thereon is that of gripping a cord  130  under tension. That is, as handle  46  is repeatedly pivoted, spool  120  is caused to rotate. Such rotation, gripping cord  130 , will draw the cord into and about spool  120 . The direction of travel of cord  130  is represented by arrow  132 . Spool  120  includes opposed bosses  134 ,  136  journalled in frames  12 ,  14 . 
         [0043]    Referring jointly to  FIGS. 12, 13, 14 and 15 , a second variant spool useable with ratchet  10  will be described. As particularly shown in  FIG. 12 , spool  140  is formed by a cylinder  142 . The cylinder includes a central passageway  144  extending therethrough. A lateral passageway  146  interconnects with the central passageway. Discs  148 ,  150  are mounted on the spool in fixed relationship with respect to one another to provide a space therebetween and to expose a certain width of the cylindrical surface of the spool. Laterally of disc  148  is a toothed wheel  152  of the type described above. Similarly, a further toothed wheel  154  is disposed adjacent disc  150  and of the type described above. A cord  156  may be inserted into lateral passageway  146  to exit through central passageway  144 . In operation, as spool  140  is rotated in the clockwise direction based on the illustration in  FIG. 12 , cord  156  will become wrapped about the spool between discs  148 ,  150 . The tension force exerted upon the cord will exert pressure upon underlying wrappings of the cord to preclude slippage. 
         [0044]    Referring more particularly to  FIGS. 13, 14 and 15 , further details attendant spool  140  will be described. One end of cylinder  142  includes slots  158 ,  160  for engagement with nubs  162 ,  164  of disc  148 . Thereby, the slots control the interior location of disc  148  and prevent rotation of the disc relative to the cylinder. The other end of the cylinder includes similar slots, of which slot  166  is illustrated. Disc  150  includes nubs  168 ,  170  for engagement with respective slots in the cylinder. Again, these slots control the position of the disc relative to the cylinder and preclude rotation of the disc independent of the cylinder. Toothed wheel  152  includes nubs  172 ,  174  for engagement with slots  158 ,  160  to preclude independent rotation between the toothed wheel and the cylinder. Similarly, toothed wheel  154  includes nubs for engagement with the corresponding slots in the cylinder and of which nub  176  is shown. A spacer ring  178  is mounted on cylinder  142  exterior of toothed wheel  152 . It may also include nubs  180 ,  182  which nubs engage slots  158 ,  160 . A similar spacer ring  184  includes nubs  186 ,  188  for engagement with the corresponding slots in cylinder  142 . A snap ring engages the corresponding groove  192  in cylinder  142  to retain the ring, toothed wheel and spacer ring in place. A similar snap ring  194  is engageable with groove  196  in cylinder  142  to retain the disc, toothed wheel and the spacer ring in place. 
         [0045]    To assist in introducing a cord or rope through lateral passageway  146  into central passageway  144 , a ramp  200  shown in  FIG. 15  may be employed. As demonstrated in  FIG. 14 , the ramp is inserted within central passageway  144  to locate incline  202  generally coincident with lateral passageway  146 . Thereby, as cord  204  is fed through the lateral passageway, contact with incline  202  will urge bending of the cord into central passageway  144  and it will exit the cylinder. 
         [0046]    Ratchet  10 A shown in  FIG. 16  is essentially duplicative of ratchet  10  shown in  FIG. 1  and its related figures. The main difference is that a ring  210  is mounted on the spool to segregate the spool into two sections. A first strap or webbing  212  wraps about the spool between toothed wheel  42  and ring  210 . A further strap or webbing  214  wraps about the spool intermediate toothed wheel  44  and ring  210 . Thereby, two straps may be simultaneously wound about the spool of ratchet  10 A.