1. Field
The present disclosure relates generally to locks and keys used in an electric power system. More specifically, the present disclosure relates to a novel interchangeable lock core that enables the opening of various locks using a single smart key.
2. Related Art
Modern electric power plants or transmission substations often involve many different types of locks. Some locks are used to control access, such as locks used on gates or cabinet doors, and some locked are used for interlocking, such as locks used on knife switches or ground wires. These many locks require the management of many corresponding keys, which is tedious and prone to human error.
In a substation, a conventional approach for key management involves a centralized key cabinet, which stores the various types of physical mechanical keys for the various locks. Before a field staff member can perform a switching operation, he needs to access the key cabinet and retrieve the appropriate mechanical keys. Because of the large number of the keys in the key cabinet (such as tens or even hundreds), manual retrieval of keys may result in errors. For example, the field staff member may miss a key or retrieve the wrong key, thus causing delays in the switching operation. Statistics show that the key retrieval accounts for nearly 10% of the total time necessary for the completion of the switching operation.
One embodiment of the present invention provides a lock-and-key system for an electrical power plant. The system includes a plurality of locks and a smart key. A respective lock is installed with a standardized lock core, and the lock is associated with a lock identifier (ID). The smart key includes a key head that matches the standardized lock core; a lock-ID detector configured to detect the lock ID; a rotation stopper which, when enabled, is configured to prevent rotation of the key head while the key head is inserted into the standardized lock core; and a control module configured to disable the rotation stopper based on the detected lock ID, thereby facilitating the smart key to unlock the lock by rotating the key head.
In a variation on this embodiment, the system further includes a smart key management module configured to determine whether the smart key is allowed to unlock the lock based on a user of the smart key and/or the lock ID.
In a further variation, the smart key further comprises a transceiver module configured to communicate with the smart key management module.
In a further variation, the smart key management module is further configured to maintain an operation record of the smart key.
In a further variation, while determining whether the smart key is allowed to unlock the lock, the smart key management module is further configured to perform a switching-error-prevention simulation.
In a variation on this embodiment, the lock further includes a radio-frequency identification (RFID) tag configured to store the lock ID, and the lock-ID detector is an RFID reader.
In a variation on this embodiment, the standardized lock core is a tubular lock.
In a variation on this embodiment, the rotation stopper is a spring-loaded sliding pin.
In a further variation, while disabling the rotation stopper, the control module is configured to retract a plug to enable the spring-loaded sliding pin to slide horizontally.
The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.
In the figures, like reference numerals refer to the same figure elements.
The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
Embodiments of the present invention provide a lock-and-key system that enables the use of a single key for opening different types of locks. The system includes various types of locks and a smart key. The various types of locks are all installed with a standardized, interchangeable lock core. The standardized lock core has a uniform pin profile that matches the key profile of the mechanical component of the smart key. In addition, each lock core is associated with a unique identifier that can be read by the electrical component of the smart key. During an attempted unlocking operation, once the mechanical component of the smart key engages with the lock core, the smart key reads the unique identifier of the lock core and determines whether the smart key is allowed to open the lock based on the unique identifier and a security or safety policy received by the smart key. The policy specifies which locks are allowed to be open at the instant moment. If the smart key is allowed to open the lock, the electrical component of the smart key activates the unlocking command, which enables the rotation of the mechanical component, thus unlocking the lock. Otherwise, the mechanical component is prevented from rotation, and the unlocking operation fails.
Outer casing 102 encloses other components of lock core 100 and enables coupling between lock core 100 and the body of a lock, such as a padlock or a deadlatch lock. Plug 104 can be rotated by a key, and thus when combining with other components of the lock, such as the shackles of a padlock, enables the locking and unlocking of the lock. A number of bearing balls, such as bearing balls 114 and 116, are placed between outer casing 102 and plug 104. Because the bearing balls are slightly larger than corresponding holes on plug 104, under normal conditions when no key is inserted into lock core 100, any attempts to rotate plug 104 against outer casing 102 is stopped by these bearing balls pushed against outer casing 102. On the other hand, when a matching key is inserted into lock core 100, the pins (such as pins 106 and 108) are pushed against the springs (such as springs 110 and 112) to a location where holes on the pins are aligned with the holes on plug 104. Consequently, the bearing balls can shift into those holes on the pins when plug 104 is rotated against outer casing 102, thus no longer preventing the rotation of plug 104 against outer casing 102. Once the key is removed, springs 110 and 112 will force pins 106 and 108, respectively, to move back to their original positions.
The standardized, interchangeable lock core shown in
The shape of key head 302 matches the shape of the standardized, interchangeable lock core. In other words, when inserted into the lock core, key head 302 pushes all pins in the lock core into positions which allow the rotation of the plug inside the lock core. Hence, rotations of key head 302 can result in the rotations of the plug inside the lock core, which unlocks the lock. However, under normal conditions, rotations of smart key 300, and thus key head 302, are inhibited by sliding pin 306, which fits into a hole on the lock core and acts as a rotation stopper. The horizontal movement of sliding pin 306 is controlled by spring 304 and solenoid-controlled plug 310. In
When a holder of smart key 300 insert key head 302 into the lock core of a lock, lock-ID reader 308 is brought to the vicinity of the lock-ID chip, thus being able to read the lock ID. The lock ID is then sent to MCU 314, which verifies whether the holder of smart key 300 is authorized to unlock the lock based on the detected lock ID. If it determines that the unlocking operation is authorized, MCU 314 issues an unlocking command that causes solenoid-controlled plug 310 to move downwardly toward plug-position detector 312. In one embodiment, the unlocking command causes electrical current to flow into a solenoid wrapped around plug 310, thus generating a magnetic force which moves plug 310.
In order to manage the use of the smart key, embodiments of the present invention also include a computerized smart key management system. The computerized smart key management system can reside on any type of computer system based on microprocessors, such as a standalone mainframe computer, a cluster of computer servers, or a portable computing device.
Smart key management system 500 includes a user-interface module 502, a lock-ID management module 504, a key-privilege management module 506, a switching-error-prevention module 508, an information exchange module 510, and a log management module 512.
User-interface module 502 provides an interface to the user of the smart key. Before a user is allowed to use the smart key to unlock any lock, the user is required to log into smart key management system 500. Lock-ID management module 504 maintains a record of all locks and their corresponding lock IDs within the substation. A system administrator is able to add or delete a lock record when corresponding changes happen in the field. Key-privilege management module 506 manages user privileges. Depending on the ranks and work responsibility of the users, each user is assigned certain key privileges that allow him to unlock a subset of locks.
Switching-error-prevention module 508 enforces the interlocking logic that prevents switching-sequence errors. Because operations of the switching devices involve unlocking corresponding locks, the switching order corresponds to the order of unlocking/locking a sequence of locks. In some embodiments, a switching-error-prevention simulation is run to make sure that the switching order, thus the order of unlocking/locking a sequence of locks, meets safety and regulation requirements. Details about the switching-error-prevention simulation can be found in U.S. Patent Application No. TBD (Attorney Docket No. YTC11-1001US), entitled “Method and System for Preventing Misoperation in an Electric Power System ,” by inventors Shuqiang Jin, Lingzhi Pang, Liguo
Wan, Jiandong Huang, and Hongping Jiang, filed TBD, the disclosure of which is incorporated by reference in its entirety herein.
The key privilege and the switching order are sent to the smart key via information exchange module 510. In one embodiment, information exchange module 510 is a wireless transceiver capable of communicating with the smart key using various wireless communication protocols, such as ZigBee or CDMA. Depending on the key privilege and/or the switching order, the smart key proceeds to perform the unlocking operations. Each time the smart key performs an operation on a lock, it sends an operation record including the lock ID of the lock to log management module 512 via information exchange module 510. Log management module 512 maintains a log file that records operations of the smart key. Such log file allows a user of smart key management system 500 to keep track of all unlocking operations.
Note that, depending whether a lock is used to control access or used for interlocking purposes, smart key management system manages the corresponding unlocking operations differently. In one embodiment, once a user logs in to the smart key management system, the system generates a list of locks that the user is authorized to open and downloads corresponding lock IDs to the smart key. Note that these locks are usually access locks, such as a lock to a storage cabinet. Because no interlocking is involved, the authorized user can open these locks at any time. Therefore, instead of sending the request each time the user attempts to open a lock, the smart key can check the lock ID against the downloaded lock-ID list to determine whether the user is authorized to open a current lock. On the other hand, before the user tries to unlock a lock involved in a switching operation, the smart key management system needs to send an order, which specifies one or more lock IDs associated with the switching operation, to the smart key. Subsequently, the smart key adds the lock IDs to the list of allowed locks if the operation is allowed, or displays an error message to the user if the operation is denied.
By implementing a standardized lock core and a smart key, embodiments of the present invention relieve the burden of managing a large number of physical keys, thus preventing key-related errors and enhancing operation efficiency. Because the smart key is controlled by the smart key management system, and is only allowed to perform authorized operations or operations that comply with safety and regulation requirements, the system eliminates the possibility of a key holder accidentally opening a wrong lock. In addition, a log is generated automatically for operations of the smart key, thus eliminating the need for the user to manually keep track of which lock has been opened. The automatically generated operation log also provides a way for an administrator or manager to monitor switching operations performed by staff members.
Note that the physical descriptions, such as shapes and dimensions of the lock core and the smart key shown in
The foregoing descriptions of embodiments of the present invention have been presented only for purposes of illustration and description. They are not intended to be exhaustive or to limit this disclosure. Accordingly, many modifications and variations will be apparent to practitioners skilled in the art. The scope of the present invention is defined by the appended claims.
This application claims the benefit of U.S. Provisional Application No. 61/509,917, Attorney Docket Number YTC11-1002PSP, entitled “Interchangeable Lock Core and Opening Method Thereof,” by inventors Shugiang Jin, Qing Chang, Hongwei Qiao, Lei Ji, and Shuiping Liao, filed 20 Jul. 2011.
Number | Date | Country | |
---|---|---|---|
61509917 | Jul 2011 | US |