Patent Publication Number: US-10781613-B2

Title: Barrel lock

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application Ser. No. 62/574,260, filed on Oct. 19, 2017, which is hereby incorporated by reference herein in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to a barrel lock and more particularly to an unlimited pre-load, rotatable barrel lock for use in the utility industry that can be installed without the use of a key. 
     BACKGROUND OF THE INVENTION 
     Utility boxes, such as electric meter boxes, are typically secured to prevent unauthorized access to the meter. Many of such boxes are secured through the use of split ring that is placed directly around the meter and locked through the use of a barrel lock. Other utility boxes, referred to as “ringless” boxes, do not include a lockable meter ring. Ringless boxes are secured by placing a lock assembly containing a barrel lock on either a side wall or a bottom wall of the box. 
     In either case, utility personal and contractors hired to install barrel locks are given security keys to do so. Each utility, however, has only one key combination so a single key can gain access to every lock in the entire system. Moreover, these keys are at times lost or stolen which creates a security problem for the utility company. 
     Furthermore, installation with a key is slower and therefore more costly than installing a pre-loaded lock. Installation of a split ring and barrel lock with the use of a barrel lock key involves multiple steps including, inserting the key into lock, activating the key and removing the lock, installing the ring onto the meter, inserting the lock into the meter ring and reactivating and removing the key. 
     In view of the above, known barrel locks are often preloaded into meter rings. One type of pre-loadable lock is a “plunger” style barrel lock. Plunger style barrel locks generally have a hollow barrel with a plunger that reciprocates axially within a bore of the barrel to lock or unlock the barrel lock. While plunger style barrel locks can offer security and variety of different lock mechanisms, design impediments exist which limit the number of possible configurations. Moreover, it may be possible to defeat plunger locks to gain unauthorized access to a meter box. 
     Another type of pre-loadable lock is a rotatable disk style barrel lock, which presents a solution to the inherent limitations of a plunger style barrel lock. An example of such a lock is described in U.S. Pat. No. 7,775,071, which is hereby incorporated by reference in its entirety. These locks require a key to pre-load the lock and are shipped to the field in a pre-load state in a product such as a split meter ring. In use, the meter ring can be installed on a meter and the lock pushed axially into a fully locked state. One problem with such pre-loadable, rotatable disk style barrel locks, however, is that in the pre-loaded state in place within the meter ring, the lock may be withdrawn from the meter ring by exerting a pulling force on the lock. 
     With the forgoing concerns in mind, it is the general object of the present invention to provide a rotatable disk style barrel lock that can be installed without the use of the key, and which does not require pre-loading in a product such as a split meter ring. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a barrel lock. 
     It is an object of the present invention to provide a rotatable barrel lock and other locking devices. 
     It is another object of the present invention to provide a rotatable disk style barrel lock that can be installed in the field without the use of an installation key. 
     It is another object of the present invention to provide a rotatable disk style barrel lock that simplifies and expedites the installation process as compared to existing pre-loadable locks. 
     It is an object of the present invention to provide a rotatable disk style barrel lock for use with utility meter boxes. 
     It is another object of the present invention to provide a rotatable disk style barrel lock that can be used with a split ring for installation on a utility meter box. 
     These and other objectives of the present invention, and their preferred embodiments, shall become clear by consideration of the specification, claims and drawings taken as a whole. 
     According to an embodiment of the present invention, a lock assembly includes a cylinder portion having an open end which receives a key. The assembly further includes a stem portion operatively connected to the cylinder portion and torsion spring operatively attached to the first and second lock portions, wherein the stem portion is capable of biased rotational movement independent of the cylinder portion. The lock assembly also includes at least one locking ball received atop the stem portion, the at least one locking ball being extendable and retractable from at least one slot in a housing of the lock assembly. A compression spring received about the stem portion biases the at least one locking ball towards a distal end of the stem. During installation into a lock receptacle, the locking ball is urged radially against the stem, causing the stem to rotate against the bias of the torsion spring, as well as urged axially rearward within the slot against the bias of the compression spring. In this position, the locking ball is positioned above a relieved area of the stem, permitting the locking ball to retract into the housing. 
     According to another embodiment of the invention, a lock assembly includes a housing having a slot, a first lock portion having an end which receives a key, a second lock portion operatively connected to the first lock portion, a first biasing mechanism configured to rotationally bias one of the first lock portion or the second lock portion relative to the other of the first lock portion or the second lock portion, and a locking ball receivable within the slot and movable in both an axial direction and a radial direction within the slot. 
     In yet another embodiment, a method of installing a barrel lock includes inserting a barrel lock having a housing and a locking member into a receptacle, the locking member being resiliently biased to an extended position where the locking member extends from the housing by a rotational biasing mechanism within the housing, and exerting an external force on the locking member to cause the locking member to move from the extended position to a retracted position where the locking member is received within the housing to allow insertion of the barrel lock into the receptacle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side elevational view a preloaded barrel lock in accordance with an embodiment of the present invention. 
         FIG. 2  is a cross-sectional illustration of a lock receptacle with which the preloaded barrel lock of  FIG. 1  may be utilized. 
         FIG. 3  is a cross-sectional top plan view of the preloaded barrel lock of  FIG. 1 . 
         FIG. 4  is a cross-sectional view of the preloaded barrel lock of  FIG. 1 , taken along line A-A of  FIG. 3 . 
         FIG. 5  is an enlarged, perspective view of a distal end portion of a stem portion of the preloaded barrel lock of  FIG. 1 . 
         FIG. 6  is a cross-sectional view of the preloaded barrel lock of  FIG. 1 , shown during insertion into a lock receptacle. 
         FIG. 7  is a side elevational view of the preloaded barrel lock of  FIG. 1 , showing the movement and position of the locking balls during insertion into a lock receptacle. 
         FIG. 8  is a cross-sectional view of the preloaded barrel lock of  FIG. 1 , taken along line B-B of  FIG. 6 , and showing the position of the locking balls. 
         FIG. 9  is a cross-sectional view of the preloaded barrel lock of  FIG. 1 , shown during insertion into a lock receptacle. 
         FIG. 10  is a cross-sectional view of the preloaded barrel lock of  FIG. 1 , taken along line C-C of  FIG. 9 , and showing the position of the locking balls. 
         FIG. 11  is a cross-sectional illustration of the preloaded barrel lock of  FIG. 1 , showing the position of the locking balls and stem during installation. 
         FIG. 12  is a cross-sectional view of the preloaded barrel lock of  FIG. 1 , shown in locked position within a lock receptacle. 
         FIG. 13  is a cross-sectional view of the preloaded barrel lock of  FIG. 1 , taken along line D-D of  FIG. 12 , and showing the position of the locking balls. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 1 and 3 , the rotatable disk style barrel lock  10  of the present invention includes a head portion  15  and cylindrical barrel body  20  extending therefrom. The barrel body  20  includes a cylindrical internal passageway  25 . The head portion  15  includes a series of protrusions  22  which engage a key (not shown) to prevent rotation of the entire lock  10  upon removal. As shown, the barrel body  20  further includes locking balls  30  which are situated in and protrude from radial slots  35  in the barrel body  20 . Importantly, as discussed hereinafter, the radial slots  35  have a longitudinal extent that is greater than a diameter of the locking balls  30 , which allows for axial movement of the locking balls  30  within the slots  35 . As will be appreciated, the locking balls  30  are configured to engage corresponding recesses in a locking device, as discussed in detail hereinafter. 
     More specifically, the locking balls  30  are configured to engage recesses, in, for example, known split retaining rings, other electricity meter rings, enclosure lid locking devices, water or gas meter and transmission locking devices, among others. As shown in  FIG. 2 , for example, a known lock receptacle  40  includes an open-ended collar  60  into which a barrel lock, such as barrel lock  10 , can be placed. An interior  70  of the collar  60  includes an annular recess  85  which accept the locking balls  30  of the barrel lock  10  when the lock  10  is pushed into the receptacle  40 . 
       FIG. 3  illustrates generally the internal components of the barrel lock  10  which are housed within the head portion  15  and barrel body  20  ( FIG. 1 ). In particular, the cylindrical internal passageway  25  of the head  15  and body terminates in a narrowed blind bore  80 . Within the passageway  25  are a cylinder  90  and a stem portion  95  extending axially from the cylinder  90 . The cylinder  90  contains combination disks  103  spaced apart by spacers  100 . The disks and spacers, which operate to lock and unlock the inventive lock, are described more fully in U.S. Pat. No. 5,086,631, which is incorporated by reference in its entirety. 
     The cylinder  90  also includes a hardened steel ball  105 . The ball  105  is located in a bore of the cylinder to prevent attempts to drill out the lock. As shown, the stem  95  extends from the cylinder  90  into the blind bore  80 . Importantly, the stem  95  is a separate component from the cylinder  90  and is rotatably attached to the cylinder  90  along with a means for rotationally biasing the stem  95  relative to the cylinder  90 , preferably a torsion spring  110 . As discussed in greater detail below, the two-piece, biased cylinder  90  and stem  95  allow for relative rotational movement that, in turn, enables the lock to be positioned in a locked state and inserted into a complementary lock receptacle without requiring a key. 
     The cylinder  90  has opposing ends; an open end  122 , which contains the combination disks and spacers utilized to lock and unlock the inventive lock, and a stem end  124  which includes a machined recess in which resides a bore. The bore serves as a means for rotatably securing the stem  95  to the cylinder  90 . As such, the bore is shaped to receive a reduced diameter attachment end of the stem  95 , which is opposite the terminal end portion containing the grooves  115 . The bore is configured to allow rotational movement of the attachment end of the stem  95 . 
     The specific configuration of the cylinder  90  and the stem  95 , and the interconnection therebetween via the torsion spring  110  is more clearly described in U.S. Pat. No. 7,775,071, which is hereby incorporated by reference herein in its entirety. As disclosed therein, a D-shaped end of the torsion spring  110  fits over a corresponding D-shaped portion of the stem  95  and prevents it from moving freely within the spring  110  thereby allowing the spring  110  to exert a rotational force on the stem  95 . As also discussed therein, a depending leg  165  engages a channel on an exterior surface of the stem end  124  of the cylinder  90 . Importantly, the spring  110  functions both as a torsion spring biasing the stem, and as a compression spring urging the combination disks toward the open end  122  of the cylinder and the stem toward the balls  30 . 
     This biased configuration is an important aspect of the present invention as the depending leg  165  of the spring  110  in the channel in the stem end  124  of the cylinder  90  creates resistance as the D-shaped end of the spring  110  attempts to rotate the stem  95  counterclockwise to lock the inventive lock. As will be appreciated, however, the channel may have various shapes and configurations as long as it can fix an end of the spring or other biasing means to the cylinder creating rotational resistance between the cylinder and stem. 
     Moreover, as will be appreciated, the biasing means need not necessarily be a spring. For example, the stem and cylinder may be interconnected simply by a flexible or pliable material that allows for the relative rotational movement between the two components. Accordingly, depending on the configuration, it may be possible for the stem and cylinder to be unitary as long as relative rotational movement is possible. 
     Referring still further to  FIG. 3 , a compression spring  130  is received about the stem  95  between a forward bearing face of the cylinder  90  and the locking balls  30  (and which may partially surround the torsion spring  110 ). In an embodiment, the compression spring  130  may include a rearward portion  132  that exerts an axially biasing force on the balls toward the forward end of the lock  10 , and a forward portion  134  integrally formed with the rearward portion  132  that does not exhibit or exert any active biasing force, but is merely utilized to transfer the biasing force from the rearward portion  132  to the locking balls  30 , as discussed hereinafter. 
     Turning now to  FIG. 5 , the stem  95  further includes a first or terminal end portion  112  having opposing, upwardly and downwardly facing, cylindrical portions  120 , and opposing grooves  115 . When the stem  95  is rotated, such as with a key, so that the grooves  115  are beneath the balls  30 , the balls  30  are permitted to retract into the radial slots  35 . Conversely, when the cylindrical portions  120  are beneath the balls  30 , they are biased outward from the slots  35  due to the large diameter of the opposing cylindrical portions  120  so that they may engage recesses  85  in a collar  60  of a lock receptacle  40 . Importantly, the convex curvature of the cylindrical portions  120 , and the concave curvature of the grooves  115  provide the cylindrical portions  120  with a large surface for supporting the balls  30  in locked position, as discussed in detail below, providing for a more reliable and secure locked state. 
     As best illustrated in  FIG. 5 , the stem  95  is also formed with flats or a relieved section  126  rearward of the cylindrical portions  120  and grooves  115 . The flats  126  define a reduced diameter portion of the stem  95  as compared to the diameter defined by the opposing cylindrical portions  120  at the terminal end portion  112  of the stem  95 . Importantly, the flats  126  are located radially offset from the cylindrical portions  120  and define therewith a saddle  128  that extends from the terminal end  112  rearward past the flats  126 . The saddle  128  defines a diameter of the stem  95  that is approximately equivalent to the large diameter defined by the opposed cylindrical portions  120 . 
     With reference to  FIGS. 3 and 4 , in use, a key can be utilized to place the lock  10  in a fully ‘locked’ position/state, where the locking balls  30  are urged forward in the slots  35  by the compression spring  130  such that they are positioned atop the cylindrical portion  120  of the stem. For example, the lock  10  may be placed in the fully locked position after manufacture and prior to shipment or deployment to the field. As best shown in  FIG. 4 , in this locked position, the balls  30  sit atop the large diameter cylindrical portions  120  of the stem  95  such that they are held in a most radially extended position in which they protrude from the slots  35 . 
     Turning now to  FIGS. 6-8 , when the lock  10  is pushed into a lock receptacle, such as lock receptacle  40 , resistance (or reaction forces) from the corner formed by the intersection of the front face  86  and the interior walls  87  (defining interior  70 ) of the receptacle  40  push against locking balls  30  to thereby urge the balls  30  longitudinally or axially toward the proximal end of the lock  10  (in the direction of arrow A in  FIG. 7 ), against the bias of the compression spring  130 . During this insertion process, a radial insertion force is also exerted on the balls  30  by this forward corner, pressing them against the cylindrical portion  120  of the stem  95 . 
     With reference to  FIGS. 9 and 10 , as the lock  10  continues to advance into the receptacle  40 , the balls  30  are forced radially inward by the forward corner and/or walls  87  defining the interior  70  of the receptacle  40 , causing the stem  95  to rotate against the bias of the torsion spring  110 . In particular, the force of the balls  30  against the edge that is formed by the curved portion  128  and the relieved section  126  of the stem  95  causes the stem  95  to rotate against the bias of the torsion spring  110  until the opposed relieved sections  126  of the stem  95  are generally aligned with the opposed slots  35  in the barrel body  20 . As the lock  10  is pushed further into the receptacle  40 , the balls  30  also move longitudinally toward the rear portion of the slots  35  and onto the relieved section  126  of the stem  95 , where they can drop radially inward.  FIG. 10  illustrates the position of the locking balls  30  after rotation of the stem  95  caused by advancement of the lock  10  into the receptacle. In this state, the lock  10  may be considered unlocked, where the balls  30  are received atop the relieved section  126  of the stem  95  and are fully retracted within the slots  35 . 
       FIG. 11  better illustrates the rotation of the stem  95  between a semi-locked state, where the force exerted on the balls  30  by insertion of the lock  10  into the receptacle  40  causes the stem  95  to rotate and the balls to partially retract into the slots  35 , and the unlocked state, where the balls  30  have caused the stem  95  to rotate approximately 25 degrees and the balls  30  are received on the relieved sections  126  of the stem  95  and retracted from the slots  35 . In particular, as the balls  30  are urged rearward against the bias of the compression spring, they ride onto an edge between the relieved section  126  and the cylindrical portion  120 . In this position, the radial force resulting from insertion of the lock into the receptacle causes the stem  95  to rotate, allowing the balls  30  to recede onto the relieve section  126 . 
     Importantly, the lock  10  of the present invention requires both an axial force as well as a radial force to be exerted on the balls  30  in order to insert the lock  10  in a lock receptacle. In particular, referring back to  FIG. 5 , if only a longitudinal force is exerted on the locking balls  30 , pushing them rearward towards the cylinder end of the lock  10 , the balls will ride onto the saddle  128  which has a diameter equivalent to the diameter of the opposed cylindrical portions  120 . This prevents the balls  30  from retracting within the slots  35 . The presence of a radial force (pressing the balls  30  towards the longitudinal axis of the lock  10 ) is required to rotate the stem  95  such that when the balls  30  are urged rearward by the accompanying longitudinal force, they are received atop the reduced diameter flats  126 , thereby allowing the balls  30  to retract within the slots  35 . In particular, the radial force transmitted to the balls  30  by insertion into a receptacle is transferred to the stem  95 , causing the stem  95  to rotate. Rotation of the stem  95  thus moves the saddle  128  out of radial alignment with the balls  30 , and presents the reduced diameter flats  126  to the balls  30 , allowing them to recede within the slots  35 . 
     Referring finally to  FIGS. 12 and 13 , as the lock is advanced even further into the receptacle  40  and the locking balls  30  align with the recesses  85  or groove in the receptacle  40 , the torsion spring  110  rotates the stem  95  to urge the balls  30  outward into the semi-locked position (shown in  FIGS. 6 and 8 ), and the compression spring  130  pushes the locking balls  30  forward in the slots  35  so that they are again received about the cylindrical portions  120  of the stem  95  and extend from the slots  35  and engage recesses  85  in the receptacle  40 . In particular, the bias of compression spring  130 , torsion spring  110 , and the absence of outside radial or longitudinal/axial forces allows the balls  30  to move forward within the slots  35  and extend radially from the slots  35  and into recesses  85 . This position is referred to as the fully locked position. 
     Any attempt to pull the lock  10  back out of the receptacle  40  in this locked state is resisted by the forward walls of the slots  35  and the larger diameter, cylindrical portions  120  of the stem  95 . That is, the compression spring  130  urges the balls  30  forward on the cylindrical portions  120  of the stem  95 , where inward radial travel of the balls  30  is prevented. Consequently, the lock  10  of the present invention allows entry into an aperture but prevents extraction without unlocking in view of the cooperative configuration and relationship of the locking apparatus components. 
     To remove the inventive lock, the key is inserted and rotated. In the unlocking cycle, the cylinder and stem operate preferably, though not necessarily, in a direct drive fashion and rotation of the cylinder rotates the stem correspondingly so that the grooves  115  are directly underneath the balls  30 , allowing the balls to recede into the slots  35 , and the lock  10  may be extracted from the receptacle. 
     As will be appreciated, the barrel lock of the present invention may be partially installed within a lock receptacle (e.g., a collar of a split ring at the factory, so as to enable complete locking of the split ring in the field merely by pushing the barrel lock completely into the collar). In addition, the barrel lock of the present invention may also be shipped in the locked state of  FIGS. 3 and 4  and pushed into a separate receptacle in the field. Thus, installation time is reduced, while increasing the ease of installation. Moreover, installers of these barrel locks need not have access to a key to facilitate locking of the barrel lock in the field. 
     In sum, the present invention provides a secure disk-style barrel lock that may be preloaded for insertion and locking in a lock receptacle without an installation key. This increases security for utilities employing such locks and provides an ease of installation. As stated, while there are known locks that may be loaded into a split ring, all are either plunger style or require them to be shipped already pre-loaded into a lock receptacle, which can have significant limitations and drawbacks. 
     While the invention has been described with reference to the preferred embodiments, it will be understood by those skilled in the art that various obvious changes may be made, and equivalents may be substituted for elements thereof, without departing from the essential scope of the present invention. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention includes all embodiments falling within the scope of the appended claims.