The present invention relates generally to a pre-loaded barrel lock and more particularly to a pre-loaded rotatable barrel lock for use in the utility industry that eliminates the need for an installation key.
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. Known preloaded locks, however, are limited to “plunger” style barrel locks. 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.
Certain rotatable disk style barrel locks present 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. 5,086,631, which is hereby incorporated by reference in its entirety. Known rotatable disk barrel locks are not, however, preloadable.
With the forgoing concerns in mind, it is the general object of the present invention to provide a preloaded rotatable disk barrel lock that eliminates the need for an installation key thereby providing a level of security unavailable with known locks. Moreover, it is a general object to provide a preloaded rotatable disk barrel lock which simplifies and expedites the installation process by eliminating the need for a key.
It is an object of the present invention to provide a preloaded barrel lock.
It is an object of the present invention to provide a preloaded rotatable barrel lock and other locking devices.
It is another object of the present invention to provide a preloaded rotatable disk style barrel lock that eliminates the need for an installation key thereby providing an increased level of security.
It is another object of the present invention to provide a preloaded rotatable disk style barrel lock that simplifies and expedites the installation process by eliminating the need for an installation key.
It is an object of the present invention to provide a preloaded lock rotatable disk style barrel lock for use with utility meter boxes.
It is another object of the present invention to provide a preloaded rotatable disk style barrel lock is preloaded into 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.
Referring to
More specifically, the locking balls 30 are configured to engage recesses, in, for example, known preloadable split retaining rings. As shown in
The male end 50 includes a bushing 80 which can be brought into axial alignment with the collar 60. The bushing 80 includes a second, deeper set of recesses 85 which accept the balls when the lock is pushed through the collar 60 of the female end 55 and into the bushing 80 of the male end 50 to secure the ring.
As stated previously, however, the only known barrel locks that may be preloaded into such split retaining rings are plunger type locks which have potential drawbacks. In particular, plunger locks may be easier to defeat and have fewer locking combinations than rotating disk barrel locks. The present invention overcomes the potential drawbacks through the use of a preloadable, rotating disk barrel lock. It is important to note, however, that the present invention may be used with other rotating barrel locks that do not utilize disks such as a pin and tumbler type lock.
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 85. 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 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 preloaded.
The stem 95 further includes a first or terminal end portion 112 with opposing flats 115. When the stem 95 is rotated so that the flats 115 are beneath the balls 30, the balls 30 are retracted into the radial openings 35. Conversely, when the cylindrical portions 120 are beneath the balls 30, they are biased outward from the openings 35 so that they may engage recesses in a collar 60 or bushing 80 of a split meter ring 40 (
Referring now to
The attachment end 124 also terminates in a shoulder 130. A front surface 130A of the shoulder 130 engages an abutment surface 126 that surrounds the bore 125 (
Referring now to
As depicted in
The spring 110 is more clearly illustrated in
This biased configuration is an important aspect of the present invention as the depending leg 160 of the spring 110 in channel 170 creates resistance as the D-shaped end 160 of the spring 110 attempts to rotate the stem 95 counterclockwise to lock the inventive lock. As will be appreciated, however, the channel 170 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.
In use, the barrel lock 10 is inserted into a collar 60 of a split ring 40 and, with the use of a key, the disks are rotated counterclockwise thereby rotating the cylinder to a locked position (
In view of the above, when the bushing 80 of the male portion 50 of the split ring is axially aligned with the interior 70 of the collar 60 the preloaded lock may then be pushed into the bushing causing the already biased stem to complete its rotation until the balls 30 are completely biased outward and protrude into the deeper bushing recesses 85 or groove securing the split ring 40.
The biased rotational movement of the stem relative to the cylinder makes this possible. In particular, as stated, when the balls are in the relatively shallow collar recesses they are not completely biased outward. While they are being forced outward by the stem and action of the spring, they cannot fully extend as their travel is limited by a bottom surface of the collar recesses. This partial extension of the balls allows them to pass out of the relatively shallow collar recess and into the deeper bushing recess when a user desires to lock the split ring. Once the balls have the clearance to extend fully outward into the deeper bushing recess, the biased stem rotates and the cylindrical portions of the stem are directly below the balls biasing them completely outward and placing the split ring in a locked position.
Referring back to
This functionality is not possible with known disk style barrel locks as they include stem portions that are rotationally fixed relative to a cylinder portion. Movement of the cylinder in these locks correspondingly moves, in a direct drive fashion, the stem so that there can be no “intermediate position” in which the balls are biased outward to partially extend into a relatively shallow collar recess where the key can be removed from the lock.
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 flat are directly underneath the balls and the lock may be extracted from a split ring.
As will be appreciated, the barrel lock of the present invention may be partially installed within the 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. Thus, installation time is reduced, while increasing the ease of installation. Moreover, installers of these pre-loaded barrel locks need not have access to a key to facilitate locking of the barrel lock in the field.
Referring now to
In sum, the present invention provides a secure disk-style barrel lock that may be preloaded into a split ring eliminating the need for 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 preloaded into a split ring, all are plunger style, which can have significant limitations and drawbacks. While these drawbacks can be addressed with disk style barrel locks, no known disk style barrel lock is preloadable. Known disk locks are not preloadable, as they do not include a stem and cylinder that provide for biased relative rotational movement.
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.
This application claims priority from U.S. Provisional Application No. 60/864,074, filed on Nov. 2, 2006, entitled “PRE-LOADED LOCK ASSEMBLY,” which is hereby incorporated by reference in its entirety.
Number | Date | Country | |
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60864074 | Nov 2006 | US |