Abstract:
A ratchet assembly for a load binder includes a pawl bearing assembly biased between a surface of the pawl and a biased movable element whose movement is actuated by the insertion or withdrawal of the lever. In one position of the movable element, the bearing assembly is urged against the pawl to lock it. In the other position of the movable element, the bearing assembly is allowed to reduce its pressure on the pawl.

Description:
FIELD OF THE INVENTION 
     This invention relates to load binder ratchet systems. In particular, this invention relates to load binder ratchet systems with removable levers. 
     BACKGROUND OF THE INVENTION 
     A load binder is typically associated with a ratchet system for tightening the binding on the load. Where large loads are involved and the ratchet is operated manually, a lever is often used. It is known to provide removable levers that allow the remaining ratchet system to keep a lower profile to the load than if the lever were still attached. An example of a removable lever is disclosed in U.S. Pat. No. 4,510,651 to Prete Jr. et al. A number of ratchet systems with removable levers are available in the marketplace. 
     The load binders for large, tightly bound loads can be dangerous. Should the tension on the load binder be suddenly released, the backlash can easily injure or kill an operator or a person attempting to steal the load. Such a risk is minimized using a sleeve the interior of which is threaded in opposite senses at each end of the sleeve as exemplified in U.S. Pat. No. 2,673,632 to Stiranka, U.S. Pat. No. 7,552,913 to Amoss et al. and U.S. Pat. No. 7,055,804 to Scott. Turning the sleeve either draws or extends the threaded eyelets at each end towards or away from each other. Such a threaded sleeve can effectively not be turned accidentally. 
     When a load has been tightened and the lever is to be removed, the pawl is usually left in its last position wherein the tension on the lines and on the gear will hold the pawl in place, thereby providing a slight locking effect on the pawl. However such effect is fairly small and can be sometimes be overcome by manipulation of the pawl into the neutral or release positions. As a result, the load binder or even the load may be subject to theft. In some cases, operators install a padlock on the ratchet system to prevent tampering with the load binder as can be seen in U.S. Pat. No. 7,055,804 to Scott. As might be appreciated, the use of a padlock can be cumbersome. 
     It is an object of this invention to provide a ratchet system for accommodating a removable lever that is easy to use, provides a locking effect on the pawl and avoids the need to use a padlock. 
     Those and other objects of the invention will be better understood by reference to the detailed description of the preferred embodiment which follows. 
     SUMMARY OF THE INVENTION 
     According to the invention, the ratchet includes a pawl locking assembly that is engaged by the removal of lever from the ratchet. 
     More specifically, the pawl locking assembly comprises a pawl bearing assembly biased between a surface of the pawl and a biased movable element whose movement is actuated by the insertion or withdrawal of the lever. In one position of the movable element, the bearing assembly is urged against the pawl. In another position of the movable element, the bearing assembly is allowed to reduce its pressure on the pawl. 
     The movable element may comprise a varying shape along its contact surface with the bearing assembly such that the pressure exerted on the bearing assembly, and therefore on the pawl, varies according to the position of the movable element. 
     According to the preferred embodiment, the movable element is elongated and translates axially along a bore and against a spring bias when the lever is inserted onto the ratchet. In its fully inserted position, the movable element urges the bearing assembly against the pawl. In its extended position, the movable element allows the bearing assembly to reduce its pressure on the pawl. 
     The foregoing embodiment admits of a movable element whose end presses axially on the bearing assembly with more or less force depending on the axial position of the element. However, in the preferred embodiment, the movable element moves axially but the bearing assembly abuts the side of the movable element. According to that embodiment, one portion of the movable element (a contact surface that abuts the bearing assembly) is radially farther from the longitudinal axis of the movable element than another portion of the contact surface, with a section between the two portions having a graduating radial distance. Movement of the element axially thereby exerts greater or less pressure on the radially-abutting bearing assembly, which in turn exerts greater or less pressure on the pawl. 
     Preferably the bearing assembly is biased (for example by means of a spring) to extend components of the bearing assembly away from one another to release pressure on the pawl in the extended configuration. In the compressed configuration (caused by abutment with the relatively larger contact surface of the movable element), the bearing assembly will exert relatively more force against the pawl. 
     Preferably, the movable element is biased (for example by means of a spring) to an extended position in which the pressure on the bearing assembly is maximized. 
     One aspect of the invention comprises a ratchet assembly. The assembly has a housing, a gear, teeth on the gear and a pawl rotatably mounted for reciprocating engagement between the teeth. A lever is adapted for selective connection to or removal from the housing. A pawl bearing assembly extends between a surface of the pawl and a biased movable element whose movement is actuated by the connection or removal of the lever from the housing. 
     In a more particular aspect of the invention, the pawl bearing assembly is biased toward exerting a bearing pressure on the surface of the pawl. 
     In a further aspect, the movable element has an extended position in which a portion thereof extends outside the housing and an inserted position in which the portion is in the housing. The bearing pressure of the bearing assembly on the surface of the pawl is greater when the movable element is in the extended position than when it is in the inserted position. 
     In a further aspect of the invention, the housing is provided with a shaped portion for removably receiving the lever. The movable element has an extended position in which a portion thereof extends outside the housing and an inserted position in which the portion is in the housing. The connection of the lever to the shaped portion causes the insertion of the otherwise protruding portion of the movable element into the housing. 
     In a further aspect, the movable element has at least two positions in relation to the housing and a contact surface in engagement with the bearing assembly. The contact surface varies axially along a length of the movable element such that a pressure exerted by the movable element on the bearing assembly, and therefore on the pawl, varies according to the position of the movable element. 
     In yet another aspect, the invention comprises a ratchet assembly in which the movable element is elongated and has a contact surface in engagement with the bearing assembly. The contact surface varies axially along a length of the movable element such that a pressure exerted by the movable element on the bearing assembly, and therefore on the pawl, varies according to whether the movable element is in an extended or in an inserted position. The movable element is translated axially along a bore in the housing to the inserted position when the lever is connected to the housing. 
     In the extended position of the movable element, a first portion of the contact surface abuts the bearing assembly. In the inserted position, a second portion of the contact surface abuts the bearing assembly. The second portion of the contact surface is closer to a longitudinal axis of the movable element than the first portion. 
     Preferably, the bearing assembly comprises two components that are spring biased to extend away from one another. 
     In yet another aspect, the invention comprises a ratchet assembly comprising a housing, a gear, gear teeth and a pawl rotatably mounted for reciprocating engagement between the gear teeth. A pawl bearing assembly extends between a surface of the pawl and a biased movable element whose movement is actuated by the connection or removal of a lever from the housing. The pawl bearing assembly is biased toward exerting a bearing pressure on the surface of the pawl. The movable element has a first position in relation to the housing in which a contact surface of the movable element abuts the pawl bearing assembly at a first radial distance from a longitudinal axis of the movable element, and a second position in relation to the housing in which the contact surface abuts the pawl bearing assembly at a second radial distance from the longitudinal axis whereby to exert less pressure against the bearing assembly than in the first position. The first position of the movable element is actuated by removal of the lever from the housing thereby causing greater bearing pressure on the bearing assembly and thus on the pawl thereby restraining it against movement. The second position of the movable element is actuated by connection of the lever to the housing thereby causing a reduction in bearing pressure on the bearing assembly and thereby releasing the pawl for reciprocation and movement about the gear teeth. 
     The foregoing was intended as a summary only and of only some of the aspects of the invention. It was not intended to define the limits or requirements of the invention. Other aspects of the invention will be appreciated by reference to the detailed description of the preferred embodiments. Moreover, this summary should be read as though the claims were incorporated herein as it is the intention that the claims also inform and be part of the present description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described by reference to the detailed description of the preferred embodiment and to the drawings thereof in which: 
         FIG. 1  is a front elevation of the ratchet assembly and a cooperating lever in accordance with the preferred embodiment; 
         FIG. 2  is a longitudinal cross-section of the body portion of a partially threaded sleeve; 
         FIG. 3  is a front elevation of an eyelet used to thread into one end of the sleeve; 
         FIG. 4  is a partially perspective view of the gear, pawl, pawl shaft, bearing assembly and pin showing their relationship to one another, with the housing removed; 
         FIG. 5  is top view of the ratchet assembly housing in which the gear and the pawl are visible; 
         FIG. 6  is a sectional view of the ratchet assembly taken along  6 - 6  in  FIG. 5 ; 
         FIG. 7  is a perspective view of the ratchet assembly in which the gear, the pawl, an aperture for receiving the sleeve and a stub for receiving the lever are visible; 
         FIG. 8  is a perspective view of the pawl of the preferred embodiment; 
         FIG. 9  is an elevation of the lever showing the socket for attaching to the stub; 
         FIG. 10  is a side view of the pin according to the preferred embodiment; 
         FIG. 11  shows the ratchet assembly and the lever in an unengaged position, but wherein the housing for the ratchet assembly has been omitted; 
         FIG. 12  is the view of  FIG. 11  but wherein the lever is engaged into the ratchet assembly whereby to urge the pin into the housing of the assembly; 
         FIG. 13  is a longitudinal cross-section of the ratchet assembly showing the pin in the position it would be in  FIG. 12 , namely with the lever engaged into the ratchet assembly; and, 
         FIG. 14  is a side elevation of the bearing assembly of the preferred embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring first to  FIGS. 1 ,  2 ,  3  and  4 , the ratchet assembly according to the preferred embodiment of the invention is generally designated by the numeral  10 . The principal components of the ratchet are the gear  12 , the gear teeth  14 , the pawl  16  and the housing  18 . A removable lever  20  is used to engage the ratchet assembly  10  and to crank the gear. Lever  20  may selectively be connected to or removed from housing  18  as will be described below. 
     Gear  12  is secured around a sleeve  22 . As seen in  FIG. 2 , the interior of sleeve  22  is threaded in opposite senses at each end of sleeve  22 . Threaded eyelets  24  ( FIG. 3 ) are sized to thread into each end of the sleeve  22 . As is well known, turning sleeve  22  in one direction will draw the two eyelets  24  toward one another thereby tightening a chain or strap attached to the eyelets and around a load, while turning it in the opposite direction will have the opposite effect. 
     Housing  18  houses gear  12  and includes opposed apertures  28  (only one being visible in  FIG. 7 ) that are co-axial with gear  12 . Apertures  28  accommodate the fitting of the housing  18  about sleeve  22 . 
     Referring now to  FIGS. 1 and 4 , pawl  16  is retained in housing  18  about a pawl shaft  35  mounted into opposed side walls  34 ,  36  of the housing. Pawl  16  is rotatable about shaft  35 . Pawl  16  has two catches  38 ,  40  at opposed ends of the engagement surface  42  of the pawl to engage the gaps  44  between the gear teeth  14 . As is well known, in normal operation of the ratchet, pawl  16  reciprocates about shaft  35  such that one of the two catches  38 ,  40  intermittently engages between the gear teeth  14 . 
     An abutment surface  41  of the pawl  16 , generally opposed to engagement surface  42 , comprises a central detent  48  used to set the pawl in a neutral position in relation to gear  12  when detent  48  is aligned with shaft  35  and gear axis  49 , gear axis  49  being indicated in  FIG. 6 . At either side of detent  48 , surface  41  comprises opposed surfaces  43 ,  45 . When either of opposed surfaces  43  or  45  is aligned with shaft  35  and gear axis  49 , the pawl is configured for a particular rotative direction of the gear  12 . In  FIG. 4 , surface  43  is aligned with shaft  35  and gear axis  49  allowing gear  12  to turn in the clockwise direction for the view of  FIG. 4 . As it turns, catch  38  of pawl  16  rides up the advancing tooth. As it does, pawl  16  seeks to rotate about shaft  35  constrained only by the bias provided by spring  80  in pawl bearing assembly  56  (see  FIG. 14  for a better view of spring  80 ). The pawl bearing assembly  56  is configured such that the spring  80  that forms a part of the assembly has a correct amount of bias to allow the assembly to yield to the rotation of the pawl  16  when the latter rides over a tooth, and to bias the pawl to rotate back into the next adjacent tooth gap  44  when the catch of the pawl has passed over the advancing tooth. It will be appreciated that when the pawl is in a selected rotative position, the angle of the catch in relation to the teeth  14  and the gaps  44  is such as to not allow the gear teeth  14  to ride over the catch in the opposite direction, as is generally understood in the art. 
     As generally seen in  FIGS. 1 ,  5 ,  7  and  13 , housing  18  includes a laterally extending square shaped stub  50  sized to be received into a square socket  52  at the end of lever  20 . A bore  54  extends axially of the stub  50  through the housing  18 . Bore  54  is offset from the pawl  16  in the housing  18  to allow for the interposition of a bearing assembly  56  between the bore  54  and the pawl  16 . A cap  58  closes the end  60  of bore  54  that is distal from the stub  50  as seen in  FIG. 13 . 
     Still referring to  FIG. 13 , an elongated binder pin  62  extends along bore  54  for axial movement along bore  54  and terminates at a spring  64  that is stopped against cap  58 . The spring  64  biases pin  62  to an extended position at which one end  66  of pin  62  protrudes out from stub  50 . 
     Referring to  FIGS. 10 and 13 , pin  62  comprises a contact surface  65  that abuts the bearing assembly  56 . Contact surface  65  has a first portion  68  that is radially closer to the longitudinal axis  67  of the pin  62  than second portion  70 . Portions  68  and  70  are separated by a beveled intersection  72 . Pin  62  is effectively wider at portion  70  than at portion  68 . 
     Bearing assembly  56  is housed in a bore  74  ( FIG. 6 ) extending radially from bore  54  and from pin  62  housed therein. Referring to  FIG. 14 , bearing assembly  56  comprises a first element  76  and a second element  78 , each having cavities opening toward the other element. A spring  80  biases elements  76  and  78  away from one another. Such a bias urges the bearing assembly (via element  76 ) to exert a bearing pressure against the abutment surface  41  of the pawl when the bearing assembly is otherwise constrained on its pin side. 
     When lever  20  is not installed over stub  50  as shown in  FIG. 11 , pin  62  is at rest with end  66  extending out of housing  18  due to the bias provided by spring  64 . The length of pin  62  is selected such that in this position, the wider section  70  of pin  62  is aligned with the bearing assembly  56  thereby compressing assembly  56  which in turn bears against surface  41  of pawl  16 . The bias provided by spring is  80  in conjunction with the overall dimensions of the bearing assembly  56  are selected such that the pressure from the bearing assembly  56  bearing on the surface  41  of pawl  16  effectively locks pawl  16  against displacement when the pin  62  is in this extended position. 
     When lever  20  is secured over stub  50  as in  FIG. 12 , end  66  of pin  62  is pressed inward and translates pin  62  axially against the bias of spring  64  to an inserted position in relation to the housing  18 . The displacement of pin  62  moves the wider portion  70  of pin  62  away from bearing assembly  56  which then abuts the narrower portion  68  of pin  62 . This position provides room for the extension of elements  76  and  78  (elements of the bearing assembly  56 ) away from one another, relieving the bias of spring  80  and reducing the bearing pressure of bearing assembly  56  on pawl  16 . This allows pawl  16  to assume a normal mode of operation wherein the pawl can reciprocate over the gear teeth  14  and can be adjusted to various operational positions. In this inserted position of pin  62 , bearing assembly  56  still exerts sufficient pressure on surface  41  to retain the pawl  16  in either rotative direction or in the neutral position, depending on whether the bearing assembly abuts surfaces  43  or  45  or detent  48  of the abutment surface  41  of the pawl  16 . 
     It will be appreciated that the invention provides for a ratchet load binder that automatically locks the pawl when a reversible lever is removed. The same mechanism operates as a pawl mode setting mechanism (either rotative direction or neutral) during normal operation of the ratchet. 
     In the foregoing specification, the invention has been described with reference to specific embodiments thereof. However, the scope of the claims should not be limited by the preferred embodiments set forth in the examples, but should be given the broadest interpretation consistent with the description as a whole. The is specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.