Patent Application
20110232342
1. Field of the Invention
The present invention is directed generally to lock mechanisms, and more specifically, to lock mechanisms that include features that permit simple and efficient access to pin assemblies and recombination of the lock mechanisms.
2. Description of the Related Art
Lock and key mechanisms have existed relatively unchanged for hundreds of years. While improvements have been made, the fundamental concept remains the same. One such lock mechanism is referred to as a pin-tumbler cylinder lock. In this type of lock, an outer housing has a cylindrical opening in which a cylindrical plug is housed. To open the lock, the cylindrical plug must rotate. The plug generally has a key slot (or “keyway”) at one end to allow a key to enter the plug and a cam or lever at the other end which may activate a mechanism to retract a locking bolt. A plurality of holes are drilled vertically into the plug and contain key pins of various lengths which may be shaped to permit a key to slide over them easily.
Above each key pin is a corresponding set of driver pins that are loaded by springs. Some locks may have only one driver pin for each key pin, but other locks requiring multi-keyed entry (e.g., a master key) may have extra driver pins and/or key pins known as spacer pins. The outer housing has several vertical shafts or pin chambers, which hold the spring-loaded pins. When the plug and outer housing are assembled, the pins are pushed down into the plug by the springs. The point where the plug and cylinder meet is called the shear point. When a proper key is inserted into the key slot of the plug, the key pins rise causing them to align with the shear point, allowing the plug to rotate and the lock to open. As can be appreciated, when no key or an improper key is in the key slot, the driver pins straddle the shear point, preventing the plug from rotating.
The springs and pins may be positioned in the pin chambers of an outer housing and retained by a cover. For example, some locks use a cover that is permanently crimped over the set of springs on an outer housing. In these types of locks, the loading and unloading of pins and springs is performed by removing the cylindrical plug, not the cover. Other locks may use individual set screws or caps to secure the pins and springs inside the outer housing. These types of locks may require special tools to remove the caps or screws. Further, locks having individual caps or screws over each pin chamber may reduce the dimensions of the pin chambers, may be difficult or time consuming to remove, or may have other shortcomings. Therefore, it can be appreciated that there is a need for an improved lock mechanism that allows for simple and efficient loading and unloading of springs and pins from pin chambers. The present disclosure describes such a mechanism, which may provide these and other advantages as is described in the detailed description and accompanying figures.
As may best be viewed in
Although other shapes are possible, the pin chambers 60, 70, driver pins 56 and key pins 58 are generally circular in cross-section. The driver pins 56 are generally cylindrical in shape with all driver pins having identical lengths. In some embodiments, the pin chambers 60, 70 include driver pins with different lengths such that, at rest, the combined stacks of driver pins 56 and key pins 58 are the same overall length. In this manner, the springs 54 are compressed by the same amount while at rest. The key pins 58 are generally cylindrical in shape at the end that abuts the corresponding driver pin 56. The opposite end of each key pin 58 may be tapered such that each key pin 58 may be pushed out of its resting position when a key contacts the tapered end. As can be appreciated, different quantities and sizes of springs, key pins, and driver pins may be included in each pin assembly. For example, in the case where a lock is manufactured to allow different keys to open the lock (e.g., a master key and a user key), each pin assembly may include a key pin and/or multiple driver pins. In one embodiment, the springs 54 are coil springs, but other forms of a resilient member may be used instead of coil springs. Functionally, the springs 54 bias the driver pins 56 and the key pins 58 toward the keyway passage 18 of the cylinder plug 16.
To retain the position of the pin assemblies within each of the pin chambers 60, 70 and to load the springs 54, a cover plate 20 and pin assembly caps 30 are provided. The cover plate 20 and pin assembly caps 30 may best be viewed in
The cover plate 20 may also include an indicator 26 operative to specify the proper orientation of the cover plate 20 to a user. Generally, the pin assembly caps 30 function to secure the cover plate 20 to the cylinder housing 12 and to restrict (or “cap”) corresponding pin assemblies positioned within the threaded pin chambers 70.
The pin assembly caps 30 each include a body portion 32 and a head portion 34. The body portion 32 includes external threads configured for threaded engagement with the internal threaded portion 72 of a corresponding threaded pin chamber 70. The body portion 32 also includes an internal cavity portion 38 sized to receive at least a portion of a corresponding pin assembly such that the internal cavity portion 38 forms part of the volume of the overall pin chambers 70. For example, a magnified section of
In operation, a user may load/unload the springs 54, the driver pins 56, and the key pins 58 into the pin chambers 60, 70. The user may then position the cover plate 20 into the recessed portion 50 of the cylinder housing 12 over the pin chambers 60, 70. As best shown in
The internal cavity 38 of each of the pin assembly caps 30 may be sized to provide substantially the same dimensions for each of the pin chambers 60, 70. As shown in
Referring to
Often, users (e.g., locksmiths) have a need to access pin assemblies positioned within a cylinder housing. As an example, a locksmith may access pin assemblies to recombinate a lock by changing one or more of the key pins, driver pins, and springs. The lock mechanism including the features described herein provides simple and efficient access to pin assemblies while providing other advantages as well. For example, in cases where the number of threaded pin chambers 70 is less than the total number of pin chambers, a user is only required to remove pin assembly caps 30 for the threaded pin chambers, and not all the pin chambers, which may save the user some time. Additionally, by providing pin assembly caps 30 having internal cavity portions 38, all of the springs 54 may be compressed by the same amount without substantially increasing the outer dimensions of the lock 10. Further, by providing the hex socket 36 (or other common socket) on each pin assembly cap 30, a user may remove the cover plate 20 and access pin assemblies using a common tool (e.g., a hex key), without the need for specialized equipment. Those skilled in the art will readily recognize other advantages provided by the present teachings.
The foregoing described embodiments depict different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely exemplary, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being “operably connected”, or “operably coupled”, to each other to achieve the desired functionality.
While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that, based upon the teachings herein, changes and modifications may be made without departing from this invention and its broader aspects and, therefore, the appended claims are to encompass within their scope all such changes and modifications as are within the true spirit and scope of this invention. Furthermore, it is to be understood that the invention is solely defined by the appended claims. It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations).
Accordingly, the invention is not limited except as by the appended claims.
