Patent Publication Number: US-10787347-B1

Title: Self-locking pulley

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Not Applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable 
     THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT 
     Not Applicable 
     INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention relates to improvements in a locking pulley is disclosed. The self-locking pulley allows a rope or strap to loop through the pulley where the pulley locks the rope or strap from movement through the pulley, but is easily pulled through the pulley. 
     Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98 
     The need to lift and hold a load has been needed for as long as ropes or straps have been used. There have been a variety of systems and methods that have been invented over years. Most of these systems use knots or pinching mechanism to hold the rope or strap. A number of patents and or publications have been made to address these issues. In the cases of knots or pinching mechanisms a user must be able to manually loosen the knot or pinching mechanism. Exemplary examples of patents and or publication that try to address this/these problem(s) are identified and discussed below. 
     U.S. Pat. No. 4,120,077 was issued on Oct. 17, 1978 to William F. Fink and is titled Tie-Down Tensioning Device. This patent discloses a device for use in tensioning the lines, ropes or cables used to tie down cargo during transport aboard a ship or other means of transportation is disclosed. An embodiment of the device is described which comprises a rigid body defining an open ended, open top channel tapering from minimum transverse dimensions at the bottom to larger transverse dimensions at the open top thereof with a hook rigidly fixed to the body at one end of the channel, a bracket rigidly fixed to the body at the other end of the channel and an opening through the body at one end of the channel having cross-sectional dimensions larger than the minimum transverse dimensions of the channel. While this patent discloses a rope pulley system it uses binding teeth to retain the rope. 
     U.S. Pat. No. 4,910,834 was issued on Mar. 27, 1990 to Donald W. Minkler and is titled Tie-Down Tensioning Device. This patent discloses a quick connect adjusting loop for a cargo tie-down rope comprises a body of substantially rigid, high strength material having a first portion forming a loop through which a loop of a tie-down rope extends and a second portion forming slip lock adjacent the loop for releasably gripping the rope. While this patent is for use with a rope it only operates in one-direction and must be untied to release the tension on the rope. 
     U.S. Pat. No. 6,685,171 was issued on Feb. 3, 2004 to Charles j. Lob et al., and is titled Lifting Device. This patent discloses a lifting device comprises a rotatable pawl with a pawl arm held in a pawl sleeve. The pawl has an open position in which a rope may be freely adjusted in tightening or loosening directions, and a closed position in which the rope is lockably engaged between the pawl and the pawl sleeve. The pawl has a pawl arm against which the locked rope may be directed to rotate the pawl into an open position. While this patent is for a lifting device, it requires a person to open the pawl, and if the lifting device is elevated it may be difficult to release the rope. 
     U.S. Pat. No. 9,604,087 was issued on Mar. 28, 2017 to Christopher Brown et al., and is titled Rope Climbing Systems and Methods of Use. This patent discloses Various apparatuses for rope-climbing and associated methods are provided. Embodiments include a circular loop of rope and a variable braking system allowing for a freely suspended rope-climbing experience a safe distance from the ground and at a speed variable to individual users. This patent is essentially for a person to continuously climb a rope and is not a releasable lifting system. 
     What is needed is a locking pully that can be released from any direction by altering the angle between the pinching plates. The proposed self-locking pulley disclosed in this document provides the solution. 
     BRIEF SUMMARY OF THE INVENTION 
     It is an object of the self-locking pulley to hold a rope or strap at a desired level of elevation. This allows a person to pull on a rope or strap that elevates a load. When the load reaches the desired height, releasing the rope or strap will self-lock the load at the height. 
     It is an object of the self-locking pulley to accommodate a variety of ropes with different diameters. The rope or strap is threaded through the locking pulley in the desired direction. At some places, the threading passes the rope or strap in opposing directions to cause a binding and prevent free movement of the rope or strap in one direction. 
     It is another object of the self-locking pulley to have a variety of pulleys that allows free movement of the rope or strap around the pulleys. There are no one-way clutches to lock movement in a particular direction. There are no locking teeth that binds the rope, nor a clutch or a cam that pinches the rope. 
     It is another object of the self-locking pulley to be fabricated with at least two interconnected pieces. A first piece is secured to a mount or ceiling. The second part can pivot and move up-and-down on the first piece. A threaded member alters a frictional lock between the at least two interconnecting pieces. The interaction of the at least two pieces allows for lifting, locking and lowering of a load on the rope or strap. 
     It is still another object of the self-locking pulley to include a spinning connection at one end of the locking pulley. The spinning connection allows a user to walk around a suspended locking pulley and pull the rope or strap from any direction. This does not restrict use from pulling the rope or strap in a particular direction. 
     Various objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the invention, along with the accompanying drawings in which like numerals represent like components. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
         FIG. 1  shows a front perspective view of a self-locking pulley. 
         FIG. 2  shows a rear perspective view of the self-locking pulley. 
         FIG. 3  shows a rope threaded through the self-locking pulley. 
         FIG. 4  shows a left view of the self-locking pulley with a rope or strap being pulled in a locking direction. 
         FIG. 5  shows a left view of the self-locking pulley with the rope or strap being pulled in a loose direction. 
         FIG. 6  shows a right view cross-sectional view of the self-locking pulley. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     It will be readily understood that the components of the present invention, as generally described and illustrated in the drawings herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the system and method of the present invention, as represented in the drawings, is not intended to limit the scope of the invention, but is merely representative of various embodiments of the invention. The illustrated embodiments of the invention will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. 
     ITEM NUMBERS AND DESCRIPTION 
     
         
         
           
               20  self-locking pulley 
               30  moving pulley 
               31  moving bar 
               32  roller 
               33  roller 
               34  curved shoulders 
               35  bent arm 
               36  side plates 
               37  roller 
               38  horizontal bracket 
               39  horizontal roller 
               40  control unlocking eye bolt 
               41  compression spring 
               42  washer 
               43  tapped hole 
               44  threaded portion 
               49  opening 
               50  fixed pulley 
               51  fixed bar 
               52  two rollers 
               53  opening 
               54  self-locking nuts 
               55  “U” bracket 
               56  bolt 
               57  shoulder bolt 
               58  friction pad 
               59  radiused side 
               60  radiused side 
               61  reinforcing ribs 
               89  rope 
               90  first placed 
               91  threaded 
               92  through 
               93  over 
               94  down 
               95  passed through 
               96  passes 
               97  pass 
               98  pulling down 
               99  loose direction 
           
         
       
    
       FIG. 1  shows a front perspective view of a self-locking pulley  20  and  FIG. 2  shows a rear perspective view of the self-locking pulley  20 . The self-locking pulley  20  is made from two essential parts, the moving pulley  30  and the fixed pulley  50 . The body of the frame for these pieces is made from aluminum, but other materials are contemplated. The fixed pulley  50  is a fixed bar  51  with an opening  53  where the moving pulley  30  passes through the opening  53  to control the rope or strap (rope or strap not shown in these figures). 
     The bar  51  has an opening where two rollers  52  are placed side-by-side. The use of two rollers  52  allow rope or strap to pass and roll in opposite directions through the opening where the pulleys are used. The top of the fixed bar  51  has a “U” bracket  55  that is secured with a bolt and self-locking nuts  54  on a bolt  56 . This allows the fixed bar  51  to freely turn and a user can lift, lock and release a load from any direction. The “U” bracket  55  has a cross shoulder bolt  57  for securing the self-locking pulley  20  in an overhead arrangement. While the self-locking pulley  20  is intended for an overhead use, it is contemplated that the self-locking pulley  20  can be used in other orientations. It is contemplated that reinforcing ribs  61  can be incorporated into the fixed bar  51  to increase the strength around the opening  53 . 
     The moving pully  30  has a moving bar  31  with a bent arm  35  that is bent to fit through the opening  53  in the fixed bar  51 . The bent arm  35  is square or rectangular in cross-section to prevent or minimize rotation of the bent arm  35  in the opening  53  in the fixed bar. The side plates  36  are held onto the bent arm  35  with a shoulder bolt or other fastener. An overhead roller  37  or pully is retained with a shoulder bolt or other fastener to the side plates. The roller  37  or pully allows a rope to pass through the opening between the side plates. The addition of the side plates  36  on the bent arm  35  prevents the moving bar  31  from being drawn through the opening  49 . 
     A pair of curved shoulders  34  are on the sides of the bent arm where the bent arm joins to the body of the moving bar  31 . The back of the moving bar  31  has a horizontal roller  39 . Secured to another “U” horizontal bracket  38 . There are openings and rollers  32  and  33  for the rope or strap to pass through the moving bar  31 . 
     The moving bar  31  includes an adjustment that sets the distance between the moving bar  31  and the fixed bar  51 . In the embodiment shown, the adjustment is with an control unlocking eye bolt  40 . The control unlocking eye bolt  40  is threaded into the moving bar  31 . A compression spring  41  and washer  42  is secured with the control unlocking eye bolt  40 . Adjustment of the control unlocking eye bolt  40  changes the amount of exposure of the threaded portion  44  of the control unlocking eye bolt  40 . This sets or adjusts the gap between the two plates and the amount of pressure on the rope or strap. A smaller diameter rope or strap will have a smaller gap, while a larger diameter rope or strap will have a larger gap. An alternate tapped hole  43  is placed at an angle through the moving bar  31 . The tapped hole  43  is an alternate embodiment for the control unlocking eye bolt  40  to allow for adjustment of the gap between the plates of the self-locking pulley  20  from under the self-locking pulley  20 . 
       FIG. 3  shows a rope threaded through the self-locking pulley  20 . The rope  89  can be threaded through the self-locking pulley  20  in either direction. In this example, the rope  89  is first placed  90  through the overhead pully or roller  37  that is held by side plates  36  on the bent arm  35  of the moving bar  31 . The rope  89  is then threaded  91  down and through  92  the opening that has the two rollers  52 . The rope  89  is then threaded over  93  and down  94  between the moving pulley  30  bar  31  and the fixed bar  51 . The rope  89  is then passed through  95  the under roller  32 . The rope  89  then changes direction and is wrapped over the horizontal roller  39  that is held on the horizontal bracket  38 . While a rope  89  is shown in some of the figures it should be equally understood that a strap could equally be used in the self-locking pulley  20 . 
     The rope  89  is then passes  96  through the over roller  33  and then over the other two roller  52 . This allows each of the two roller  52  to spin in opposite directions. The rope will then pass  97  downward. Pulling down  98  will lock the rope  89  in the self-locking pulley  20 , while pulling on the rope  89  with allow the rope  89  to be pulled through the self-locking pulley  20 . 
       FIG. 4  shows a left view of the self-locking pulley  20  with a rope  89  being pulled down  98  in a locking direction. When the rope  89  is pulled down  98 , as shown in this figure the tension on the rope  89  pulls the moving bar  31  against the fixed bar  51 . This is accomplished by the rope  89  pulling on the horizontal roller  39  that pulls the moving bar  31  against the fixed bar  51  with the tension on both paths of the rope  89 . The control unlocking eye bolt  40  is adjustable to change the extension of the threaded portion  44  between the moving bar  31  and fixed bar  51 . This unlocks the amount that the rope is compressed between the moving bar  31  and fixed bar  51  to frictionally hold the rope  89 . 
       FIG. 5  shows a left view of the self-locking pulley  20  with the rope  89  being pulled in a loose direction  99 . When the rope  89  is pulled in this direction  99 , the tension in the rope lifts and rotates the moving bar  31  and the bent arm  35  is pulled into the opening  53 . In this orientation, there are no pinching or clamping forces on the rope  89  between the fixed bar  51  and the moving bar  31 . The rope  89  can then freely move around the pulleys and rollers  37 ,  52 ,  32 ,  39 ,  33  and  52  again. In both  FIGS. 4 and 5  the side plates  36  and the overhead roller  37  can rotate from the bent arm  35 . Any adjustment to the control unlocking eye bolt  40  and the eye bolt extension threaded portion  44  does not affect the movement of the rope  89 . 
       FIG. 6  shows a right view cross-sectional view of the self-locking pulley  20 . This view shows the curved or radiused sides  59  and  60  of the opening  53  in the fixed bar  51 . This reduces any frictional forces between the bent arm  35  in the opening  53  and further allows the bent arm  35  of the moving bar  31  to pivot within the opening  53 . The rollers  32 ,  33  and  52  that allows the rope to pass, and move through the self-locking pulley  20  are shown. The overhead pulley or roller  37  is shows hanging on the side plates  36  through a pivot bolt  45 . Roller  39  is shown secured and elevated or displaced from the back side of the moving bar  31 . 
     In the top portion of this figure, the self-locking pulley  20  is shown suspended with a bolt  56  that holds the “U” channel  55  on the shoulder bolt  57 . The control unlocking eye bolt  40  is further shown extending through the moving bar  31  with a threaded portion  44  on the other side of the moving bar  31 . This figure also shows heat plates or friction pads  58  that are secured to the locking pulleys with fasteners or the like and are replaceable as they wear to prevent the sides of the locking pulley from wearing as the rope causes friction on these surfaces. 
     Thus, specific embodiments of a self-locking pulley have been disclosed. It should be apparent, however, to those skilled in the art that many more modifications besides those described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims.