Abstract:
An apparatus for the rapid removal of components of a cylinder type lock includes a retention member for accepting a portion of a fastener which has been inserted into the keyway of a cylinder, a sliding yoke connected to the retention member and a pivoting handle for moving the yoke. The yoke and retention member are constrained to linear travel in either a forward or rearward direction enabling the extraction of the plug inline with the lock cylinder in a single movement of the handle.

Description:
FIELD 
     The present invention relates generally to an apparatus for extracting portions of cylinder type locks, and similar locks that are flush mounted or semi flush mounted to a door or other surface. More specifically, the apparatus enables the rapid removal and replacement of components of locks such as those used in safe deposit boxes in the banking industry. 
     BACKGROUND 
     Keyway cylinder removal tools or “lock pullers” of various types are known in the art. Typically, lock pullers permit the pulling of the “plug” from cylinder locks for replacement purposes. One type of destructive entry tool used by locksmiths that can extract either the entire cylinder or the plug alone from a safe deposit box and thereby provide access to the locking mechanism is the so-called “Bell” cylinder puller. In order to use the Bell device, a threaded fastener; typically a wood screw, is screwed into a keyway of a plug where it is held fast. The head of the fastener is temporarily retained by a portion of the tool that is coupled to one end of a lead screw positioned longitudinally within a cylindrical housing. At the end of the lead screw opposite the screw retaining portion is a hex nut. When the hex nut is turned, e.g., by a wrench, the retainer moves in an opposite direction to the housing which is braced against the mounting face of the lock, thereby drawing out the cylinder plug. The majority of destructive entry tools currently employed for removal of cylinder locks for replacement purposes are variants of the Bell device. 
     Other types of plug extractors have been described in the past. U.S. Pat. No. 4,707,903 to McCartney describes a nose plug puller for rekeying a Mosler type safe deposit box lock which includes a pull shaft that is partially threaded, a support, a nut and a cam key. Although the McCartney device teaches these as separate elements, when assembled, the device operates similarly to the Bell device whereby a cylinder plug is pulled by turning a lead screw. The plug is pulled by using the lock mounting surface to push against. 
     U.S. Pat. No. 6,725,697 to Leadon describes a keyway cylinder plug removal tool for a safe deposit box that uses a hole saw to cut through the retaining lip portion of a nose surround to free the plug. 
     While working well for their intended use, the foregoing devices are time consuming due to the number of turns required of the lead screw in order to draw out the cylinder plug; a distinct disadvantage in cases where multiple locks must be replaced en masse. 
     It would be desirable to provide a lock puller that extracts plugs much more rapidly than previous devices. 
     It would be desirable to provide a lock puller that performs the forgoing extraction without damage to either the face plate or plug surround. 
     It would be further desirable if such a lock puller were easy to use, requiring little practice in order to gain proficiency. 
     It would be especially desirable if the lock puller were readily adaptable to the majority of safe deposit box locks in use. 
     SUMMARY 
     The present invention relates generally to a cylinder plug extractor. More specifically, the apparatus of the present invention greatly expedites replacement of lock cylinders such as those used in safe deposit boxes. In the embodiment depicted herein, the apparatus assembly includes a frame which includes two plates side by side, wherein each plate has an elongate guide in the form of a slot, and the plates are aligned in the frame assembly. A u-shaped yoke resides between the plates. Supported transversely relative to the frame by the u-shaped yoke, a follower in the form of a transverse cross pin rides within the elongate guides. A post or shaft extends from the closed end of the yoke. At the distal end of the post is a fastener retention member which is slotted to accept the head portion of a fastener; typically a wood screw that has been inserted into the keyway of a cylinder lock. Between arms of the yoke and positioned radially on the follower is a radial bearing. A second cross pin positioned transverse the plates defines a pivot point for a handle, a portion of which includes an arcuate bearing guide. The arcuate bearing guide of the handle surrounds the radial bearing which follows the arc of the bearing guide when the handle is moved. When the handle is moved downwardly, this action has the effect of drawing the retention member, the fastener and the cylinder plug linearly in a backwards direction as the follower tracks with the elongate guide. It should be noted that while the particular embodiment depicted in this disclosure has a curved bearing guide which when moved relative to the radial bearing, forces the bearing and yoke forward or backward, the particular degree of arc of the bearing guide can be varied to draw the yoke at different rates relative to the pivoting action of the handle. 
     In one aspect of the present invention, the action of a pivoting handle extracts a cylinder plug by pulling the plug inline with; and outwardly from the cylinder. 
     In another aspect of the present invention a pivoting handle moves a guide that is tracked by at least one follower. The follower is linked to a fastener retention member that accepts and reversibly retains a portion of a fastener partially threaded into a keyway of a lock. 
     In the foregoing aspects, the fastener retention member is constrained to move in a linear direction by the follower tracking an elongate guide of the assembly. 
     It will be appreciated by those of ordinary skill in the art that the overall size of the apparatus of the present invention can vary. While preferably, the bearing guide is an arcuate aperture, it is also conceivable that it can be a arcuate or curved recess. The material of the apparatus can be of any sufficiently rigid material to withstand the pulling force of the handle transmitted to the fastener retention member when surround  212  is braced against the mounting surface of a lock. While surround  212  of the preferred embodiment is a rigid tubular construction, a plastic flange or rim  232 , can be fitted to the end of the surround as a non-marring spacer, stabilizer or alignment aid to assist a user in maintaining proper contact and perpendicular alignment with the lock mounting surface when pulling plugs. It is also conceivable that the frame be adapted to accept a handle or grip, preferably extending from the bottom or sides of the frame or even as part of the alignment aid above, to assist a user with applying force to a lock mounting surface in order to maintain flush contact with the surface. Such a grip would be attached to the frame by any suitable means including a threaded shaft or attachment bracket. 
     The foregoing and other objects, features, and advantages of the invention will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures wherein the scale depicted is approximate. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top plan view of one preferred embodiment according to the present invention; 
         FIG. 2  is a side plan view of the embodiment of ( FIG. 1 ) taken in the direction of arrow (a); 
         FIG. 3  is a bottom plan view of the embodiment of ( FIG. 2 ) taken in the direction of arrow (b); 
         FIGS. 1 a -3 a    depict handles extending respectively from ( FIGS. 1-3 ); 
         FIG. 4  depicts in a partial schematic, a side view of a preferred embodiment wherein the handle is inline with the frame and fastener retainer member is fully extended; 
         FIG. 5  in a continuation of ( FIG. 4 ), handle is moved downwardly and retainer member is retracted fully into surround; 
         FIG. 6  in a continuation of ( FIG. 5 ), handle is moved further downwardly and retainer member is further retracted; 
         FIG. 7  in a continuation of ( FIG. 6 ), retainer member is fully retracted; 
         FIG. 8  in a partial side view shows a preferred embodiment according to the present invention wherein retainer member placed over a threaded fastener that has been screwed into a cylinder keyway; 
         FIG. 9  in a continuation of ( FIG. 8 ), retainer member is shown being retracted with the cylinder plug being extracted from the lock; 
         FIG. 10  shows in side and top plan views a reversibly attachable stabilizing and alignment aid for attachment to the surround. The flange has a stabilizing portion and a tubular portion with a notch shown in dashed line that aligns with surround cut-out  213  when the tubular portion is placed over the surround; 
         FIG. 11  is a partial perspective view of a preferred embodiment according to the present invention; 
         FIG. 12  is a top down perspective view of yoke and retention member assembly. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference Listing 
     
         
           100  frame assembly 
           210  frame 
           211  elongate guide 
           212  surround 
           213  surround cut-out 
           214  fastener retaining member 
           216  post 
           218  yoke 
           220  follower 
           222  radial bearing 
           224  handle 
           226  bearing guide 
           228  handle pivot 
           230  bushing 
           232  stabilizing aid 
           300  threaded fastener 
           400  lock 
           500  plug 
       
    
     Definitions 
     In the following description, the term “follower” or “guide shaft” refers to a cylindrical post, pin or radial bearing that tracks a “guide,” which is typically a straight or curved aperture or recess. Unless otherwise explained, any technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The singular terms “a”, “an”, and “the” include plural referents unless the context clearly indicates otherwise. Similarly, the word “or” is intended to include “and” unless the context clearly indicates otherwise. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of this disclosure, suitable methods and materials are described below. The term “comprises” means “includes.” All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety for all purposes. In case of conflict, the present specification, including explanations of terms, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting. 
     Referring generally to  FIGS. 1-12 , a preferred embodiment according to the present invention for extracting components of a cylinder type lock includes a frame  210  having a surround  212  an elongate guide  211 , a pair of cross members transverse the frame; one of which defines a follower  220  residing within guide slot  211 , and a second cross member that defines a pivot point  228  for handle  224 . A yoke  218  residing within the frame supports the follower and is connected to a fastener retention member  214  by post  216  which can be threaded into the body of retention member enabling the distance of the retention member to the lock mounting surface to be adjusted by rotating the retention member. Also, the post can be threaded into the yoke, and the retention member swivelable upon the post so that distance of the retention member to a mounting surface can be adjusted by rotating the post to extend or retract the same. Other means of adjusting the starting distance of the retention member to a lock mounting surface will suggest themselves to those having skill in the art and access to this disclosure. It is conceivable that the retention member possess recessed plural inline spaced notches to receive and reversibly retain the head portions of fasteners at varying distances. Radial bearing  222  mounted on the follower tracks the contour of bearing guide  226  when the handle is moved. When the handle is moved downwardly, the bearing guide which is eccentric to the handle&#39;s pivot point, moves up and draws radial bearing  222  rearwardly. Because the follower is connected to the yoke and travels within elongate guide  211 , both the yoke and the retention member are constrained to linear travel. It should be noted however, that the orientation of the bearing guide can be reversed or the apparatus can be rotated so as to retract the retention member when the handle is moved upwardly or to the side. 
       FIGS. 1-3  depict respectively, a top plan view, a side plan view and a bottom plan view of a preferred embodiment. Surround  212  encircles retention member  214  with the exception of cutout  213  that permits a threaded fastener to enter from the side of the surround for reversible coupling with the retention member which is slotted to accept the head of the fastener. Radial bearing  222  can be a roller bearing, or conceivably a bushing or sleeve that rotates about follower  220  and moves freely within bearing guide  226 . 
       FIGS. 4-7  illustrate the movement of the individual components from an unretracted state ( FIG. 4 ), to fully retracted ( FIG. 7 ). Cross member  228  and follower  220  which define respectively, a pivot point for the handle, and a sliding support for the yoke are preferably centrally unthreaded shafts such as a carriage bolt, lag bolt or similar. Spacers or bushings  230  can be used to offset the handle and the yoke from sides of the frame. When the handle is moved downwardly, bearing guide  226  pivots in direction (c) drawing bearing  222  rearwardly. Bearing  222  is supported upon follower  220  which is in turn supported by yoke  218 . Because the follower is constrained by elongate guide  211 , the yoke and retention member are likewise constrained to linear forward or backwards travel when the handle is moved up or down. 
     Moving to  FIGS. 8 and 9  with reference again to  FIGS. 4-7 ; in order to use the present invention, a one way insert is placed in the keyway of a cylinder lock. The insert can be a threaded fastener  300  as depicted in the preferred embodiment or a tapered element having surface irregularities that once inserted into a keyway, resists withdrawal therefrom. With the plug removal tool unretracted, retention member  214  is slipped around the head of the fastener and the surround braced against the mounting surface (ms) of the lock, such as the door face of a safe deposit box. Handle  224  is pulled down, causing bearing  222  to follow within the contours of eccentric bearing guide  226 . Yoke  218  is drawn linearly and rearwardly as follower  220  slides within guide  211  drawing with it the retention member, engaged fastener  300  and cylinder plug  500 . 
     It should be understood that the drawings and detailed description herein are to be regarded in an illustrative rather than a restrictive manner, and are not intended to be limiting to the particular forms and examples disclosed. The configuration of a handle, handhold or grip of the tool can be of any design and can be for one or two-handed operation. Accordingly, it is intended that this disclosure encompass any further modifications, changes, rearrangements, substitutions, alternatives, design choices, and embodiments as would be appreciated by those of ordinary skill in the art having benefit of this disclosure, and falling within the spirit and scope of the following claims.