Abstract:
The tie-down provides an adjustable strap under control of a ratchet during retraction and pay-out. The tie-down is provided with a strap issuing rearward from a transverse bar between base sides, the bar being an integral part of the base, three sides having been rolled up from the base bottom into a C-shaped bar opening rearward. A forward strap issues forward from the tie-down secured to a spindle to which ratchet wheels attach. The forward strap wraps the spindle during tie-down strap retraction.

Description:
BACKGROUND 
       [0001]    1. Field of the Invention 
         [0002]    This invention relates to tie-downs, as may be used to secure a load to a vehicle. 
         [0003]    2. Prior Art 
         [0004]    It is known to have a tie down assembly that secures a load to a vehicle. Typical is that tie-down assembly disclosed by Anthony et al. in U.S. Pat. No. 5,282,706 in which Anthony et al. describes an assembly secured directly to a chassis with a strap issuing therefrom for connection around or to a load. The strap is wrapped around a spool and unwound on release to pay out as necessary. When the strap is secured about the load, the strap is released and it automatically retracts around the spool. The strapping apparatus, U.S. Pat. No. 7,350,767 is also known. Other prior art references are also known, these references being only typical. 
       SUMMARY OF THE INVENTION 
       [0005]    The ratchet-based tie-down of the present invention features a spindle as a ratchet spool without a retraction spring. In a pay out configuration, a forward directed strap simply unwinds from the spool under user pulling action, without spring bias to rewind. A rearward directed strap extends from the tie-down without length adjustment to assure against slippage in length of the rearward directed strap. Without a retraction spring; when the spindle not connected to anchor points under strap tension, the spindle remains in payout unless and until it is positively rewound by a user onto the spindle. 
         [0006]    A forward hold on the base holds a ratchet crank out of engagement with a ratchet wheel, allowing the spindle to rotate freely. A rearward hold on the base holds the crank in a locked position in which the crank captures a locking plate when the locking plate is engaged with the teeth of the ratchet wheel, preventing the ratchet wheel from rotating, thus holding straps of the tie-down taut to forward and rearward anchor points to which they may be attached, respectively. 
         [0007]    As in ratchet based tie-downs of the prior art, a ratchet spool, or instead in this instant configuration, a spindle without a retraction spring, extends between sides of a tie-down base. Particular to this instant configuration, the spindle comprises two semi-cylindrical halves with opposing diametric surfaces slightly spaced apart. Ends of each of the halves extend through matching holes on each side of the ratchet wheels therein providing a heavy-duty link between the wheels and the crank. The spindle halves continue through the crank sides and through matching holes in base sides, thus connecting the base sides and crank sides rotationally about the spindle. 
         [0008]    The tie-down is configurable between a pay-out mode or configuration and a retraction, or ratchet, configuration. With the tie-down assembly in pay-out mode the user simply pulls the strap out without a counter bias from a retraction spring as it unwinds from a spindle, or spool. 
         [0009]    The strap is tightened to a load when the tie-down is moved to its retraction mode. Reconfiguration between modes requires positive action by the user so there is no inadvertent switch between operation modes. In retract mode, a crank is repeatedly lifted and lowered in effecting a ratcheting of the spindle rotation in strap retraction. A ratchet plate engages teeth of a ratchet wheel attached to the spindle to secure the spool from releasing when the crank is lowered in normal ratcheting retraction operation to engage a new pair of ratchet teeth on the ratchet wheels. 
         [0010]    A lock plate engages the ratchet wheel teeth to lock against rotation of the ratchet wheel, taking the ratchet wheel out of ratcheting operation. To return the ratchet wheel to ratchet operation, the crank is lifted forward into operation position which releases the lock plate from ratchet teeth. A cam on the crank also moves the lock plate away from the ratchet wheel as the crank is moved forward allowing the ratchet wheel to freely rotate through the ratcheting mechanism. 
         [0011]    The tie-down is changed from ratchet mode to pay-out mode by moving the crank forward over a forward hold that is beyond a normal ratcheting range of motion locking the crank forward as the ratchet plate and the lock plate are both withdrawn from the ratchet wheel allowing it to rotate freely. Thus, in pay-out mode the strap is pulled by the user without restriction. 
         [0012]    A further feature of the invention incorporates the rearward strap attached rearward on the base on a base buckle that includes a “C shaped” bar transverse the tie-down between base sides. This is a design feature that is an improvement over a bolt and nut typical of the prior art in that its C shaped structure provides an enhanced strength and flexural resistance much improved over a bolt and nut configuration where the strap passes over a nut transversely attached to base sides by nuts. The bar is formed by stamping three sides of a generally rectangular shape out of the base bottom and further including attachment ears on cut corners that connect to the base sides. The three sided rectangular is then rolled from the base bottom back toward the uncut rectangular side forming the C shaped opening rearward with the ears secured into matching holes in the base sides. This rear strap bar structure then improves the tie down structure by simplifying the design and configuration and inherently reduces failure of the tie down from breakage of parts as parts are eliminated, which also helps reduce construction cost. It also provides an increase in strength by the rear strap bar being unitary with the base bottom. 
     
    
     
       BRIEF DECRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a perspective view of the tie down of  FIG. 1 . 
           [0014]      FIG. 2  is an exploded isometric view of the tie down of the present invention. 
           [0015]      FIG. 3  is a bottom view of the tie down of  FIG. 2 . 
           [0016]      FIG. 4  is a side view of the tie down of  FIG. 2 . 
           [0017]      FIG. 5  is a perspective view of the base of the tie down of  FIG. 2   
           [0018]      FIG. 6  is a side section view of the base of  FIG. 2  showing the connection of the rearward strap to the base. 
           [0019]      FIG. 7  is a top planar view of the base of the present invention prior to it being stamped and folded. 
           [0020]      FIG. 8  is a cut-away perspective view of the rear strap bar. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0021]    The tie down  1  of the present invention comprises a base  10  and a crank  30  mutually pivoting at a spindle  40  by a ratchet action. 
         [0022]    The base  10  includes opposing base sides  11  upstanding from a base bottom  12 , each side  11  having a base spindle hole  13  for receiving the spindle  40  that rotates coaxially within the base spindle holes  13  between the base sides  11 . The crank  30  includes crank sides  31  spaced apart by a spacer  32  that extends intermediate the length of each of the crank sides  31  between the crank sides  31 . Crank sides  31  partially overlap the base sides  11  outside the base sides  11  as the base sides  11  and the crank sides  31  mutually pivot at the spindle. A crank handle  32  extends between crank sides  31  rearward in the crank  30 . The crank  30  also has a pair of crank holes  33  on respective crank sides  31  aligned with the base holes  13  such that the spindle  40  passes rotatably through the aligned holes  13 ,  33 . A ratchet wheel  50  is located between respective base  11  and crank sides  31  align coaxially with the spindle  40  and aligned base spindle and crank holes  13 ,  33  and orthogonal to the base and crank sides  11 ,  31 . 
         [0023]    The spindle  40  is forward in the tie-down and comprises two half spindles  41   a ,  41   b  disposed with opposing diametric faces  42  spaced apart. Ends  43  of each half spindle  41   a ,  41   b  fit into matching semi circular holes  51  in the respective ratchet wheels  50  with each semi circular hole  51  receiving a half spindle end  43  such that as the crank  30  rotates the ratchet wheels  50 , the spindle  40  also rotates. The half spindles  41   a ,  41   b  are held in place in the semi-circular holes  51  by pins  44  passing through pin holes  45  in ends  46  of the half spindles  41   a ,  41   b . A forward strap  60  wraps around the spindle  40 , for example with a forward strap end  61  passing between the half spindles  41   a ,  41   b  to bind the forward strap  60  to the spindle  40  such that as the crank  30  rotates the forward strap  60  further wraps or unwraps the spindle  40 . 
         [0024]    The tie-down functions in the normal manner of a ratchet to controllably rotate the spindle.  1 n implementing the ratchet  70 , each crank side  31  has a crank through side slot  34  angled radial to the spindle  40 . A ratchet plate  71  extends between the crank sides  31  (and over the base sides  11 ) disposed to engage both ratchet wheels  50  at respective crank sides  31 . The ratchet plate  71  is withdrawn from engagement with ratchet teeth  72  by a user&#39;s pull of a ratchet release  73  that is connected to the ratchet plate  71 . Typically, the ratchet release  73  and the ratchet plate  71  are a single piece with opposite ends defining the ratchet plate  71  and the ratchet release  73 . Ends of the ratchet plate  71  fit slidably in a radial direction with respective to the spindle  40  in respectively crank side slots  34 , into and out of engagement with the ratchet teeth  72 . The ratchet plate  71  is disposed to be pulled radially outward by action of the ratchet release  73  or released radially inward under bias of a first spring  75 . Thus, sliding the ratchet plate  71  inward through the crank side slots  34  causes the ratchet plate  71  to engage the ratchet teeth  72 . Similarly, sliding the ratchet plate  71  outward through the crank side slots  34  causes the ratchet plate  71  to disengage from the ratchet teeth  72 , therein allowing the crank to rotate with the ratchet plate  71  outside of the ratchet teeth  72 . 
         [0025]    With the crank  30  rotated rearward generally, the ratchet plate  71  may be pulled further outward, also radially, and lifted over a rearward hold  15  that is on an upper edge  16  of each respective base side  11  to a rotational position  17  behind the rearward hold  15  on the edge  16  of the base side  11  therein preventing the crank  30  from rotating until the crank side  31  is lifted back over the rearward hold  15  to rest on the edge  16  of the base side  11  forward of the rearward hold  15 . 
         [0026]    To effect a ratchet wheel lock, a lock plate  80  is provided in the base  10 , extending between base sides  11  and passing through base slots  17 . As with the crank slots, the base slots  15  are directed radially to the spindle  40  and ratchet wheels  50  below the crank  30 . As the crank  30  is rotated rearward with the ratchet plate  71  rearward of the rearward hold  15 , a notch  36  in the respective crank sides  31  engage the lock plate  80  in the lock plate lock position  81 , that is, with the lock plate  80  engaging the ratchet teeth  72 , thus preventing the lock plate  80  from moving rearward out of engagement with the ratchet teeth  72 . In the lock position  81 , the ratchet wheels  50  and thus the spindle  40  are prevented from rotating. The lock plate  80  is released by lifting the crank  40  such that the notch  36  does not engage the lock plate  80 . A lock spring  82  continues to bias the lock plate  80  into engagement with the ratchet teeth  72 . As the crank  30  is further lifted and the ratchet release  73  is pulled backward as the crank  30  is rotated forward to a forward side  18  of the rearward hold  15 , a cam  19  forward on the crank respective sides  31  engages the lock plate  80  and moves the lock plate  80  rearward out of engagement with the ratchet teeth  72 . The cam  19  continues to move the lock plate  80  away from the ratchet teeth  72  as long as the ratchet plate  71  is forward of the rearward hold  15 . In the reverse crank motion, the cam  19  releases from engagement with the lock plate  80  allowing the lock plate  80  under spring bias to engage the ratchet teeth  72  as the lock plate  80  is received into the notch  36 . The notch  36  is prevented from engaging the lock plate  71  except when the crank  30  is lowered rearward of the rearward hold  15 . 
         [0027]    With the ratchet  70  thus enabled, as the crank  30  is lowered, the ratchet plate  71  continually slides over the ratchet teeth  72  from one pair of teeth  72   a  on respective ratchet wheels  50  to a subsequent pair of teeth  72   b . When the crank motion is reversed the ratchet plate  71  engages the ratchet teeth  72  and rotates the ratchet wheels  50  as the crank  30  is moved forward relative to the base  10  in the normal method of ratcheting. 
         [0028]    A forward hold  20  is located forward on respective base side edges  16 . The ratchet plate  71  may be pulled by the ratchet release  73  radially away from the ratchet teeth  72  and over the forward hold  20  on each base side  11  into engagement with a forward notch  21  on the forward side  22  of the forward hold  20  radially outward from the ratchet teeth  72  thus preventing the ratchet plate  71  from engaging the ratchet teeth  72 . With the crank  30  forward, the cam  19  continues to maintain the ratchet plate  71  and the lock plate  80  disengaged from the ratchet teeth  72 . Thus, the spindle can rotate freely, normally unwinding. 
         [0029]    To effect a tie-down tightening action, as noted above the forward strap  60  is secured around the spindle, the forward strap  60  extending forward. Further, a rearward strap  62  is secured to the tie-down, extending rearward. As the spindle  40  is rotated as described above the effective combined strap length is extended or shortened, which combined strap comprises the forward and rearward straps  60 ,  63  joined by the tie-down therebetween. 
         [0030]    A rear strap bar  90  is cut out of the base bottom  12  by three sided stamping. The bar  90  is then rolled from the base bottom  12  leaving a hole  95 . The bar  90  is rolled upward from the base bottom  12  about a uncut fourth side  94  that remains integral with the base  12 . The bar includes ears  91  on each bar end  92  that fit into bar receiving holes  93  in the base sides  11  that are of size to receive the ears  91  as base sides  11  are bent upward from the base bottom  12  on each base side  11  which provides attachment of the bar  90  to the base bottom  12 . With the ears in the rear strap bar  90  received into bar receiving holes  93 , the rear strap bar  90  is prevented from moving further rearward past the bar receiving holes  93  under pull of the rear strap  96  under load. The rear strap  96  secures to the rear strap bar  90  by entering around the rear strap bar  90  through a hole  95  in the base bottom  12  and then wrapping around the rear strap bar  90  and back upon the rear strap  96  to which it is affixed therein securing the rear strap against slippage in length under load in its securement to the rear strap bar  90 . 
         [0031]    and secures the rear strap  96  against slippage in length in its securement to the rear strap bar  90 . 
         [0032]    In summary, then the invention disclosed herein comprises 
         [0033]    A tie down including a base and a crank mutually pivoting at a spindle by a ratchet action, the base including opposing base sides upstanding from a base bottom, each base side including a ring and having a base spindle hole in each ring for receiving the spindle, which spindle rotates within the base spindle holes between the base sides, the crank including crank sides spaced apart and further including a crank handle extending between crank sides, the crank having a pair of crank holes on respective crank sides that are aligned with the base holes together with ratchet wheels with ratchet teeth at each spindle end such that the spindle passes rotatably through the aligned crank and base holes, the tie down adapted to receive a forward strap in attachment to the spindle to extend forward from the tie down and adapted to receive a rearward strap in attachment to the base to extend rearward from the tie down such that as the crank is rotated forward with the base and crank pivoting apart in cooperation with the ratchet action, the effective length of the combined forward and rearward straps is reduced, the improvement comprising:
       a rearward lug rearward on and projecting outward from said curvilinear outer edge,   a ratchet plate slidable in respective crank side slots directed toward the ratchet wheel, the ratchet plate extending between the crank sides and including a ratchet plate leg portion disposed to releasably engage and disengage from teeth of the ratchet wheels, the ratchet plate leg portion movable between a ratchet condition forward of the lug and a lock condition rearward of the lug, wherein the ratchet plate moves generally along the outer edge during said ratchet action with the ratchet plate in said ratchet condition wherein movement of the ratchet plate between said ratchet and lock conditions is effected by lifting said ratchet plate leg portion over said rearward lug and wherein the crank is prevented from rotating when said ratchet plate is in lock condition,   a lock plate slidable in respective base side slots directed toward teeth of the ratchet wheel, the lock plate extending between the crank sides and including a lock plate leg portion disposed to releasably engage teeth of the ratchet wheels, preventing the ratchet wheel from rotating rearward as the ratchet plate disengages from said teeth and said crank and ratchet plate rotate rearward with the base and crank pivoting together in said ratchet action,   wherein at least one of said crank sides has a notch such that with the lock plate in engagement with the teeth, as the crank with ratchet plate lowers into said lock position, the lock plate is received into said notch, preventing the lock plate from disengaging from the teeth and thus the ratchet wheel from rotating.   a forward lug forward on and projecting outward from said curvilinear outer edge,   a cam on the crank sides moving the lock plate out of engagement with the ratchet teeth when the rotating plate in the crank is rotated over and forward of the forward lug from said ratchet condition to a forward position wherein the ratchet plate is supported out of engagement with the said teeth and wherein movement of the ratchet plate between said ratchet condition and said forward position is effected by lifting said ratchet plate leg portion over said forward lug, wherein with the crank with ratchet plate in forward position the spindle can rotate freely with the ratchet plate and the lock plate out of engagement with the teeth the ratchet wheel,   a rear strap bar attached between the base sides, the rear strap bar being unitary with the base bottom being bent therefrom on a strap bar side that remains integral with the base,   wherein the rear strap bar comprises an ear on each rear strap bar side that fits into a rear strap bar receiving hole in each base side, the respective rear strap bar receiving holes being of size to receive the respective ears therein preventing the rear strap bar from moving rearward past the bar receiving holes under pull of the rear strap under load,   wherein the rear strap bar is adapted to receive the rear strap in securement thereto by the rear strap entering through a hole in the base bottom and then wrapping around the rear strap bar and back upon the rear strap to which it is affixed therein securing the rear strap against slippage in length under load in its securement to the rear bar,   wherein the rear strap bar is formed with three sides of the rear strap bar having been cut and rolled up from the base bottom into a C-shaped bar opening rearward of the tie down, wherein the rear strap bar is formed with three sides of the rear strap bar having been cut and rolled up from the base bottom into a C-shaped bar opening rearward of the tie down, and   wherein said hole in the base bottom is formed as the rear strap bar is cut and bent out of the base bottom.