Patent Grant
9663972
The invention relates to locking mechanisms used in filing and storage cabinets, office furniture, storage compartments, including built in cabinets, and other lockable storage units.
Many furniture manufacturers and their customers desire electronic locking mechanisms that use a keypad or other electronic means, such as an RFID Card reader or other security scanner, rather than traditional mechanical locks, to access and secure their office furniture and other kinds of storage units. In many instances, electronic locks are desirable to avoid the costs and inconvenience associated with replacing lost keys, rekeying locks because of staffing changes or security breaches, and the like. Manufacturers and users often prefer programmable electronic locks which can be reprogrammed to deal with staffing changes, and other security concerns, and to, for example, monitor access and usage of the locking devices, and the associated storage units.
Electronic locks in the prior art have been used to provide secure storage and access control in office furniture, storage cabinets and other compartments. These prior art locks have special latching mechanisms and housings which require the furniture manufacturers and others to make tooling changes to their furniture or make other potentially time consuming, difficult, and costly adaptations to accept the special locking mechanisms and housings of these prior art locks as replacements for pre-existing locking systems.
By way of example, FIG. 1 in published US Patent Application 2011 0056253 shows such an electronic lock with a unique housing and latching apparatus. FIGS. 1, 2, 3 and 4 of U.S. Pat. No. 6,655,180 also show an electronic lock with a unique housing and latching system requiring custom installation.
Similarly FIG. 5 of U.S. Pat. No. 5,886,644 shows a unique installation of outer and inner housings for an electronic lock.
Furthermore, neither of these locks can be used with lateral filing cabinets or pedestal drawers because they cannot be easily adapted to existing central locking systems.
Canadian Patent No. 2,388,230 shows an example of a mechanical lock used in a central locking application for a lateral filing cabinet or other storage unit. In FIGS. 1 and 2 of that Patent, the mechanical lock is shown with a zigzag shaped lock shaft and a round retainer. The illustrated lock shaft is connected to a locking core which is included in a standard “Double D” lock housing unit. An example of this mechanical lock is shown as being installed in a conventional 2 drawer locking cabinet.
Prior art locking systems come in various shapes, sizes and configurations. Many of these prior art locking systems include multi component drawer slide locking arrays.
Therefore, it is desirable to provide a new electronic locking system that is conveniently interchangeable with existing mechanical locks without requiring costly tooling changes by office furniture manufacturers, and without using difficult or complicated installation procedures by installers, customers or other users.
By way of example, it is preferable that an electronic lock include a replaceable or interchangeable driver selected from a group of preselected drivers of different shapes, sizes, and configurations, the group being compatible for use with a plurality of tenons, cranks, linkage bars and other components in locking systems which are widely used in many standard locking applications within the industry.
In some instances, electronic locks of the prior art include a solenoid device operating with a linear action. Typically, this linear action engages or disengages a latching bolt or engages a shear pin to prevent a knob from turning.
Often, these prior electronic locks use a substantial number of batteries connected in series and require a large housing to store the batteries. Typically, these batteries require frequent replacement. Solenoid motors are not generally recommended for locking applications because their performance may be affected, or security features may be compromised, by strong magnets which may be brought into close proximity to the solenoid motors.
Many electronic locks in the prior art use DC motors to drive their latching mechanisms. US Patent Application 2007/0257773 Brian Hill et al shows an example of such a mechanism. The motor required to rotate the gear train including 7 gears draws a significant current and requires a large battery capacity. Typically this type of electronic lock requires 4 or more “AA” batteries which are installed in a separate housing inside the storage cabinet. The service life of these batteries is such that the batteries must be replaced frequently, thus leading to increased operating costs for users of these electronic locks.
In some prior art electronic locks, piezo-electric motors may be used to drive the latching mechanisms. However, such piezo-electric motors are typically more expensive than other conventional electric motors. In addition, piezo electric motors typically draw substantial electric currents, thus leading to shortened battery life and increased operating costs associated with frequent replacement of batteries.
Further, these prior electronic locks often utilize latches and detents to ensure that the lock can either be in a locked position, or in an unlocked position, to avoid a continuous application of electrical power from a substantial battery power supply.
Accordingly, it is also desirable to provide an electronic lock design which avoids a substantial consumption of electrical power.
It is also desirable to provide a compact electronic lock design.
It is also desirable to provide an alternative electronic lock design with enhanced security features.
It is also desirable to provide an electronic lock design, preferably with programmable features, to enable users to adapt the electronic lock to meet one or more user needs.
It is desirable to provide an electronic lock design which incorporates one or more of the foregoing features, or other useful features.
In one aspect, an electronic lock is designed to be installed in a storage unit. When installed, the electronic lock is operationally associated with a locking assembly (for example, a locking bar assembly) for locking and unlocking a storage unit (for example, storage units suitable for one or more storage compartments). In this aspect, the electronic lock includes a lock housing which can be releasably secured to the storage unit. The electronic lock may be adapted for use in retrofit installations, as a replacement for previously installed locks, or as an original equipment manufacturers' (OEM) component.
Various features and components may be used to releasably secure the electronic lock housing to a storage unit. Fasteners, couplings, quick connect and other elements may be provided to secure the electronic lock, yet allow the manufacturer, installer or other user to remove the electronic lock, if replacement, repair or removal for some other reason, is desired.
It is preferable that the housing is replaceable or interchangeable with other housings selected from a group of preselected housings of different shapes, sizes, and configurations, the group being compatible for use with a plurality of other locking systems which are widely used in many standard locking applications within the industry.
The electronic lock includes a driver to operationally engage the locking assembly. Typically, the driver moves between a first driver position and a second driver position. In the first driver position, the locking assembly is in the locked position. In the second driver position, the locking assembly is in the unlocked position.
Preferably, the driver is replaceable or interchangeable with other drivers selected from a group of preselected drivers of different shapes, sizes, and configurations, the group being compatible for use with a plurality of tenons, cranks, linkage bars and other components in locking systems which are widely used in many standard locking applications within the industry.
A drive shaft assembly is protected in the housing. The drive shaft assembly is adapted to be selectively and operationally engaged with the driver. For example, an operator may select a locked position for the electronic lock in which the drive shaft assembly will not activate the locking assembly in the storage unit. In one mode, such as for example, when the electronic lock is in the locked position, the drive shaft assembly is operationally disengaged from the driver so that the driver is unable to lock or unlock the locking assembly in the storage unit. Similarly, by way of example, the operator may select an unlocked position for the electronic lock in which the drive shaft assembly may be operationally engaged with the driver, so that the operator may manually unlock the locking assembly.
The electronic lock includes a gear segment assembly which moves between a first gear segment position and a second gear segment position. In the first gear segment position, the drive shaft assembly is operationally disengaged from the driver. In the second gear segment position, the drive shaft assembly is operationally engaged with the driver.
The electronic lock also includes an electronic access control to operate the gear segment assembly between the first gear segment position and the second gear segment position. The electronic access control will, often, but not necessarily, include an operator activation device such as a programmable keypad or a programmable access card reader (for example, and RFID card reader). The electronic access control may include an electric motor in combination with a rechargeable or replaceable battery power source. The electric motor may be used to move the gear segment assembly to the second gear segment position, so that the operator may operationally engage the driver, to, in turn, operate the locking assembly between a first position in which the locking assembly is “locked” (for example, to prevent opening of the storage unit) and a second position in which the locking assembly is unlocked (so that the locking assembly may be moved by the operator, between the locked and unlocked positions).
In a preferred embodiment, when the electronic lock is in the unlocked mode, and the electric motor has moved the gear segment assembly to the second gear position, the operator may manually operate the driver by rotational movement, or other movement, of the drive shaft assembly. Preferably, the motor may be used sparingly to operate the gear segment assembly, without operating the entire drive shaft assembly, to reduce power consumption and thus, prolong battery life, or reduce the frequency of battery recharging or replacement.
A port, such as a USB port, may be provided to allow convenient recharging of a suitable rechargeable battery and to allow data storage, data access or exchange with the electronic access control.
The electronic lock in this aspect also includes a manual activation assembly which is operationally connected to the driver when the gear segment assembly is in the second gear segment position. In this mode, the operator may manually operate the driver between the first driver position and the second driver position. In preferred embodiment, the manual activation assembly includes a manually operated knob which the operator may rotate, to move the drive shaft assembly and to operate the driver so that the locking assembly may be operated between its locked position and its unlocked position.
The manual activation assembly may also provide a bypass feature. In certain situations, for example, when the motor in the electronic access control is not operational (or for administrative convenience), the bypass feature may be activated to permit the operator to manually operate the drive shaft assembly, without using the motor to move the gear segment assembly to the second gear segment position. In some instances, the bypass feature may allow the operator to manually move the gear segment assembly to the second gear segment position (for example, when the motor is not operational). In other embodiments, the bypass feature may allow the operator to activate other elements to operationally engage the drive shaft assembly with the driver. In some instances, the bypass feature may operationally engage the drive shaft assembly with the driver without activating or moving the gear segment assembly to the second gear segment position.
For example, in some embodiments, the bypass feature may include a key activated locking core to operationally engage the drive shaft assembly with the driver, without moving the gear segment assembly. The operating key may be inserted by the operator into the locking core, to turn the drive shaft assembly, and in turn, move the driver so that the locking assembly in the storage unit may be moved between the locked and unlocked positions.
In another aspect, an electronic lock operates between a locked position and an unlocked position, to allow an operator to lock and unlock a storage unit. In this aspect, the electronic lock comprises:
In yet another aspect, an electronic lock operates between a locked position and an unlocked position to lock and unlock a locking assembly in a storage unit. In this aspect, the electronic lock may include:
By way of example, in some embodiments, the third shaft segment may include a keyed locking core configured to operate the drive shaft without activating the electronic access control or without drawing power from a battery power source to operate an electric motor or other electronic components. In other embodiments, the third shaft segment may be configured to operate separately from the manual activation assembly. In some instances, one or more of the shaft segments may be constructed from multiple components or pieces.
The invention includes a method of operating the electronic lock including the steps of:
The passcode may be provided to the electronic lock by manually entering the passcode via a keypad, or by communication with a permitted electronic device. For example, the passcode may be scanned by a card reader, or the passcode may be detected by communication with a computer, smartphone, an RFID enabled device, an NFC device, or other type of device capable of communicating the passcode to the electronic lock, or more particularly, to a controller in the electronic lock.
In another aspect, the method includes applying power to a motor for linear movement of a gear assembly to engage the drive assembly with the locking system in the storage unit. The method may include switching steps to stop the application of power to the motor when the gear assembly has completed a movement of the gear assembly between the disengaged position and the engaged position.
In another aspect of the invention, the motorized movement of the gear assembly between the disengaged position and the engaged position corresponds to an operational engagement of a first portion of the drive assembly with a second portion of the drive assembly. In the disengaged position, the manual drive assembly will not operate the locking system between the locked position and the unlocked position. In the engaged position, the first portion is engaged with the second portion of the drive assembly, permitting the user to operate the locking system between the locked and unlocked position, to allow the user to gain access to the storage unit.
The method may include storing data relating to the operation of the electronic lock in a memory element (such as for example, a removable flash drive, memory card, or some other compatible memory element).
The method may also include activating a manual bypass element, to permit manual operation of the locking system, without operating the motor to engage or disengage the gear assembly with the manual drive assembly.
The invention includes a system for operating an electronic locking system in a storage unit. The system may include:
The system may also include a manual bypass to permit access to the electronic lock without motorized operation of the gear assembly.
The manual bypass may be lockable to prevent unauthorized use of the manual bypass to operate the manual drive assembly.
The system may include an electrical component selected from the group of components consisting of:
Other methods, systems, and software will also be readily apparent to persons skilled in the art, having regard to the more detailed description provided herein.
There are other possible embodiments of this invention which may include interchangeable drivers, interchangeable housings, electronic access control features which may include a programmable keypad, a programmable card reader, a manual bypass feature, a removable chassis, interchangeable electronic components including a controller and modular circuits, and one or more of the other features described elsewhere within this specification. An optional modular chassis assembly may also be provided in which a removable array of components are assembled in a modular format for testing, maintenance, repair, convenience, or improved quality control during assembly of the electronic lock. A preferred embodiment of the invention is described having regard to the following drawings.
Other aspects of the invention will become apparent to those persons who are skilled in the art upon reading the following detailed description, drawings and appended claims.
Electronic locks of the prior art are not readily or easily adapted for retrofit installation in storage units fitted with prior art latching systems.
The lock housing insert 5 extends from the interchangeable rear housing plate 4 of the lock housing 3. The lock housing insert 5 is configured to fit within a corresponding opening with a like configuration in a storage unit. The lock housing insert 5 may be cast with the rear plate 4 as one piece. In other embodiments, the lock housing insert 5 may be a separate piece 4a secured (in some other manner) to a suitable back plate piece.
A drive shaft 7 extends rearwardly from the lock housing 3 toward the interior of a storage unit (not shown). A driver 9 extends from the distal end of the drive shaft 7. The driver 9 is provided to connect with a locking system in a storage unit (which may be similar to an existing unit similar to the locking system described in Canadian Patent No. 2,388,230. Preferably, the driver 9 is interchangeable with other replacement drivers. A substitute driver may be attached to a suitably configured drive shaft segment which may also differ in configuration from the drive shaft 9 illustrated in
Different drive shaft configurations may be accommodated within the interior of the lock housing 3. The drive shaft, driver and housing components may be interchangeable with other replacement components to allow the electronic lock 1 to be interchangeable with comparable mechanical locks or other electronic locks. The interchangeability of these components enhances the adaptability of the electronic lock system for simplified repairs and replacements of existing locks and in OEM manufacture.
A keypad 15 is provided as part of an electronic access control situated on the proximate face of the electronic lock 1. In this embodiment, keypad 15 includes an external protective keyboard membrane 44 and a front gasket 44a. The keypad 15 supports the entry of pass codes and programming commands via a keyboard circuit 42 into the memory element included in circuit board 40 by regular users and master users. Indicator light array 45 is connected to the circuit board and the power supply, to notify the operator of one or more status indicators associated with the maintenance and operation of the electronic lock. A USB port and cover 17 are provided on the side face of the lock housing 3. The USB port may be provided to facilitate recharging of the interior power storage (battery 33) used to power the electronic components of the electronic lock 1 including a battery powered rotary motor 32. In this embodiment, the USB port cover 17 is shown as a flexibly hinged attachment to a protective gasket 18 positioned between the interchangeable housing rear plate 4 and the housing frame 3a.
A manual knob assembly 11 surrounds a rotatable bypass (override) key core 13. The manual knob assembly 11 includes a knob grip 14 which extends outwardly from the housing front plate 3b. The knob grip 14 is secured to a manual knob 14a which partially extends inwardly, away from the front plate 3b. When the knob grip 14 is secured to the manual knob 14a (for example, in a snap fit configuration), the manual knob assembly 11 is rotatably secured to the housing front plate 3b. In other embodiments comprising a lock housing 3a, a dummy plug (not shown) may be permanently installed so that a keyed bypass feature is not available. Some customers may wish to avoid the risk of the keyed lock being picked and therefore those customers may choose to decline the keyed bypass feature.
The knob barrel 14b nests within knob 14a, and knob barrel cap 14c is positioned within knob barrel 14b, in a predetermined alignment so that the matched internal channels and abutments may selectively engage with the locking core 13 in the event that the operator chooses to operate the manual knob assembly in a manual override mode. The manual knob assembly 11 engages with a front drive gear 22 mounted about the knob barrel cap 14c, both of which are mounted on a fixed collar 3c projecting in a forward direction from the chassis 3f located within the housing frame 3a. Inner cam 14f is positioned rearwardly of the chassis 3f. The inner cam 14f extends through the interior channel of the collar 3c.
When the electronic lock 1 is in a locked state, the manual knob assembly 11 and the drive shaft 7 are not engaged and will not permit operation of the driver 9. In the disengaged state, the manual knob 14a spins freely.
Once the appropriate passcode has been successfully entered and accepted by the software, the motor 32 begins to rotate. Ramped collar cam 30 which is mounted on the motor shaft also rotates. This collar cam 30 interacts with the ramped follower surface 29a on the first slider cam 29 so that as the collar cam 30 rotates, the slider 28 is urged away from the collar cam 30. This linear movement of the slider 28 displaces the locking dog 50 in the second slider cam 28b, to disengage locking dog 50 from recess 24e in rear drive gear 24a, to unlock and permit manual rotation of the drive shaft 7. The slider lobe 28x engages gear lobe 20x, when the slider 28 is displaced, to rotate the front and rear gear segments 20a, 20b, so that the gear segments 20a, 20b are aligned for engagement with the front drive gear 22 and rear drive gear 24a. When the knob 14 is turned, the gears 20a, 20b, 22, and 24a are meshed and the drive shaft 7 also turns. As shown in
The gear segment assembly 20 includes a front gear segment 20a located forward of the chassis 3f and a rear gear segment 20b located rearward of the chassis 3f. A gear segment sleeve 20c extends through an aperture 3h in chassis 3f to connect front gear segment 20a to rear gear segment 20b. Torsion spring 27a urges the gear segment assembly 20 in a preferred direction, preferably to hold the gear segment assembly 20, in a starting position, abutting against rest 3j, when the gear assembly 20 is disengaged from the corresponding gears of the front drive assembly 14d and the rear drive gear assembly 24 when the electronic lock is in the locked position. In this embodiment the front drive assembly 14d includes front drive gear, and parts 14, 14a, 14b and 14c. The rear drive gear assembly includes rear drive gear segment 24a.
Front gear segment 20a includes a first cam segment 21a and a second cam segment 21b. Cam segments 21a and 21b interact with the drive gear assembly, during rotation of the drive gear assembly, to activate control switches which interact with the motor, during the opening and closing steps of the electronic lock.
When the manual knob assembly 11 and the gear assembly 20 are operationally engaged and the manual knob assembly 11 is turned, the drive shaft 7 also turns. The user turns the manual knob assembly 11 through 180 degrees to open a matched locking assembly (not shown) within a storage unit (not shown). This manual action provides the power to lift locking bars, rotate cams and other locking features without electrical power. This optional power saving feature allows an operator to apply manual power to perform these steps thereby reducing the power draw from the battery 33.
The electronic lock 1 supports an optional manual override key K. The override key K bypasses the keypad 15 and allows the manual knob assembly 11 to be turned in operational engagement with the drive shaft assembly after the override key has been turned.
When tumblers (not shown) in the locking core 13 are key activated, they engage with the internal channels and abutments of the manual knob assembly 11 to enable the bypass (override) option, allowing the operator to operationally engage the drive shaft assembly and rotate it upon rotation of the locking core 13 and the manual knob assembly 11.
With reference to
An index spring 12 acts as a detent so the user can feel discrete clicks as the manual knob assembly 11 is rotated to advance through the operational steps of locking and unlocking.
In this embodiment, the indicator 31 is used to show different colours in the window lens 12a corresponding to the rotational position of the manual knob assembly 11 and whether the driver 9 has opened or closed the locking assembly. Torsion spring 27 urges the indicator 31 in a preferred direction to indicate the status of the electronic lock 1. These different colours provide the user with a visual cue showing the status of the electronic lock and its corresponding affect on the locking assembly in the storage unit: (i) fully opened, (ii) fully closed or (iii) manual knob assembly 11 is partially turned.
The electronic lock is readily adapted for use with various locking systems and storage units. A variety of interchangeable drive shafts and drivers may be provided with the electronic lock. The drive shafts and drivers are designed to fit with pre-existing locking components or standard OEM parts used by furniture manufacturers and the like. In addition, interchangeable lock housings of different configurations may be provided. For example, with regard to the example of the standard “Double D” lock housing, an opening of the same size and corresponding configuration is provided by furniture manufacturers in their furniture to accept a standard mechanical lock with a Double D mechanical lock housing. The electronic lock is easily adapted to be surface mounted on the furniture so that the housing insert 4a may be inserted as a replacement into a corresponding opening in an existing storage unit, including office furniture, fitted with a standard mechanical lock with a Double D housing.
The electronic lock is easily adapted to be installed into an existing central locking system of a storage unit in exactly the same manner as an existing mechanical lock. In a preferred embodiment, the back plate of the lock housing assembly is first mounted within the gable of the cabinet structure using a hex nut, spring clip or other means suitable to secure the housing back plate to the structure. For convenience, a template may be provided to locate a single drill hole for a mounting screw (not shown) on the cabinet structure to match a threaded opening or other fastening feature on the lock. The hole may be drilled in the cabinet (or other structure) and the screw may be threaded through the drilled hole and into the electronic lock housing to ensure that the housing does not rotate or move relative to the structure after installation. Provided that the appropriate housing insert, drive shaft and driver configurations have been selected, the installer should be able to install the electronic lock without other tooling changes.
The central locking system is installed in the same manner and configuration as with a mechanical lock.
In different embodiments, the lock drive shaft and or driver may be replaced with a plurality of shapes and sizes such as square, horseshoe or other configurations.
Opening the Lock
The electronic lock 1 is initially in the locked state as shown in
Step 1
The user enters a pass code on the keypad which is validated by the microcontroller against the data stored in the database. The data includes a pass code and other pre selected information, for example, the time of day. If the pass code is valid, then power is applied to the motor to engage the gear segment assembly to engage the manual knob assembly with the drive shaft.
Step 2
Step 3
Once the gear segment assembly 20 is engaged with both drive gears 22, 24a (e.g., the gear segments from the rear drive gear assembly 24 and the front drive assembly 14d associated with the manual knob assembly 11), the user can now turn the manual knob assembly 11 to open the locking assembly (for example, a locking bar assembly) in the storage unit.
Closing the Lock
Step 1
The user then closes a drawer or door (not shown) on the storage unit (for example, in a furniture cabinet) and turns the manual knob assembly 11 through 180° in a counter clockwise direction. This action is shown in
Step 2
As the user continues to turn the manual knob assembly 11 fully through 180°, the gear segment assembly 20 disengages and falls away and is biased away by the torsion spring 27a. In Step 2, the electronic lock is in the fully locked position shown in
Preferably, motor 32 is a relatively low cost, DC geared, small rotary motor used to rotate the collar cam 30 which in turn engages the gear segment assembly 20 and moves the slider 28 as described in more detail above. A DC geared rotary motor may be selected for one or more of the following reasons: (i) a rotary motor design may save space over several other motors alternatives; (ii) a geared motor may provide relatively high torque from a smaller motor; (iii) often, it will maintain its state without additional power; (iv) it may operate within a range of 3.0 V (or lower) to 5 Volts which means that power does not have to be regulated when used with a LiPo Battery; and (v) it may be configured for relatively low power consumption resulting from a relatively low power requirement and a relatively short duration of usage per operational cycle.
Preferably, the gear reduction is about 100:1 but other reductions such as 50:1 and 150:1 may also be used. A preferred DC geared rotary motor will allow voltage input over a 3-6 Volt range which would allow the motor to be attached directly to the LiPo battery, thus bypassing or avoiding a need for the voltage regulator.
As described in more detail above, each 180° turn with the shaft attached to the motor toggles the advanced/retracted position of the slider and gear segment assembly, thereby allowing the user to turn the knob barrel and open the lock.
Power from the LiPo battery 33 is applied to the motor 32 to accomplish each 180° turn of the shaft. In the preferred embodiment, each turn of the shaft (which is accomplished by human power) requires power to be applied for only approximately 0.25 seconds. For each full use cycle of the lock (corresponding to opening and closing the lock), the motor shaft will have accomplished two 180° turns over approx. 0.25 sec intervals each, totaling 360° and approximately 0.5 sec of power being applied from the LiPo battery. For each full open and close cycle of the lock, power usage will total approx. 0.004 mAh, or 0.00057% of the usable power capacity of the LiPo battery.
Table 1 contains a list of preferred parts for the circuit board of the preferred embodiment.
Many electronic locks use AA or AAA batteries which are physically large. In other cases, small LiPo, coin cell, or other batteries are used but they are not rechargeable. Although these battery types may be used in other embodiments of the invention, they are not preferred.
The preferred design includes a microcontroller which is powered by Lithium Ion Polymer (LiPo) battery. Preferably, the battery is rechargeable. The preferred battery is a Tenergy 852045 with a capacity of 700 mAh, although batteries of different types and capacities may be used as a matter of design choice. Although it is not an essential requirement, the preferred 700 mAh capacity will in certain embodiments provide between about 7-12 months of normal operating usage on a single battery charge.
Preferably, the battery 33 has low-discharge circuit protection. This type of circuit protection will cut-off power flow from the battery if the battery voltage approaches a level low enough to damage the battery 33. Persons skilled in the art will appreciate that this type of circuit protection is important when the battery charge level is relatively low (e.g., if the filing cabinet is left locked for a long period of time). The power flow will be cut-off so that the battery may be re-charged, without damage to the battery, or without the need for replacement of the battery.
When the battery is no longer able to hold a sufficient charge (for example, approx. 700 mAh in the preferred example) then a user may replace the battery by (i) providing a supplemental power supply via the USB Port to open the lock, (ii) removing the electronic lock from the furniture, (iii) removing the back plate, (iv) disconnecting the battery from the electrical leads, and (v) re-installing the new battery within the electronic lock and the electronic lock secured in the storage unit (for example, office furniture). Optionally, a trap door may be provided in the housing to access the battery without having to remove the lock from the furniture. This trap door may be optionally secured so that the door is opened by entering commands on the keypad.
Preferably, a voltage regulator is used to maintain the voltage at a constant 3.3V for the microcontroller. A low-dropout or LDO voltage regulator (MCP1700) may be used because it can operate with a very small input-output differential voltage. The advantages of a low dropout voltage will often include: (i) a lower minimum operating voltage, (ii) a relatively higher efficiency of operation and (iii) relatively lower heat dissipation. The regulating process is preferred to step down the voltage coming from the battery which may vary between about 3.2V to 4.2V and the USB power which may operate at about 5V.
In the preferred embodiment, the lock includes a self-containing charging mechanism and as such does not require an auxiliary charger for the battery. The preferred circuit board includes a preferred LiPo charging integrated circuit (shown in
In the preferred embodiment, the microcontroller controls the logic of the system. The System Software is resident in the microcontroller and controls the operation of the microcontroller. A variety of microcontrollers may be used as a matter of design choice. However, the ATMEL AT90USB1286 was selected in the preferred embodiment, for the following reasons: (i) low power consumption was desired and only 3.3V are required to operate the Microcontroller; (ii) the selected microcontroller supports C and C++ languages for software applications; (iii) the microcontroller includes 8 KB of non-volatile memory which is used to store user and settings data. (Non-volatile memory is not erased due to loss of power.); (iv) the preferred microcontroller supports a microSD memory card which is desirable for extensive data logging; (v) native USB 2.0 support is included which automatically formats and copies data in memory but also supports USB connect and host mode; and (vi) the preferred microcontroller includes 2 internal timers, since two timers are desired in the preferred method of lock operation.
Data inputs in the preferred system include, data inputs from 3 micro switches, a preferred 12-button keypad and a real-time clock. Optional inputs are received from the RFID/NFC antenna.
In the preferred embodiment, the System Software controls the operation of the DC geared motor, buzzer and 3 LEDs. Optionally, the System Software controls the RFID/NFC circuit.
Preferably, the System Software reads and writes data records to the microSD memory card. Preferably, it also enables access to these data records when a computer or USB device is connected via the USB port (or other data port).
Preferably, the System Software maintains a User Database with privileges within the microcontroller EEPROM/flash memory.
During locking and unlocking processes, the System Software compares user codes inputted on the keypad to the permitted codes previously entered in the User Database to limit/control access to the electronic lock.
Although other data ports are available, a USB type port is preferred. The most preferred USB port is of the Micro-A type, although Standard and Mini USB ports could also be used. The Micro-A was selected as a preferred design choice because Micro-A was believed to be (i) evolving into a future standard; (ii) more durable than Mini ports; (iii) the smallest port available and (iv) the lowest cost port available.
The USB port allows charging of the LiPo battery, and access to the data records on the microSD memory card when the USB memory mode is enabled.
Preferably, the keypad connection will accommodate a plurality of alternative keypads. With reference to
The preferred keypad is illustrated as a 12-button matrix style membrane keypad with 3 LEDs. The preferred keypad membrane is covered with a cast rubber silicone top.
In the preferred array, the 12 buttons include digits 0-9, an enter key, and a program key. These buttons allow all desirable user controls of the lock, such as for example, inputting user codes to access the lock, setting system variables like adding/removing users and muting the sound (of the buzzer or other audible alarm or warning components), and enabling system modes like the USB access mode of the system's microSD memory card.
Preferably, the real-time clock provides the calculation of UNIX Standard Time. UNIX Standard Time is preferred to date stamp and time stamp entries in the Database. Preferably, the real-time clock has two alternative power sources: the primary LiPo battery 33 and its own battery backup 74 in the event that the main battery 33 loses power. Preferably, a coin cell type battery 74 is used as a battery backup and under ideal conditions may provide about 2.5 years of backup power to ensure accurate timekeeping/data storage.
Preferably, the circuit board includes a microSD memory card for data storage. However, it will be understood that alternative storage systems, including memory cards of any size may be used. In a preferred embodiment, approx. 128 MB of storage space will, ideally, provide storage for up to 350,000 log file entries (e.g., lock openings or closings). Preferably, once the database is full, the System Software will manage the available storage space and delete the oldest records first so that up to 350,000 of the most recent actions are maintained in storage.
In the preferred embodiment, a buzzer 76 provides audible sounds corresponding events such as command success signals or command failure signals and key entry signals. The buzzer may be optionally disabled or enabled.
Micro switches 82, 84 and 86 are used by the System Software to manage the processes of opening and closing the electronic lock. In
Micro Switch 82 ensures that the rotary motor 32 turns precisely through 180° to engage and disengage the slider 28 and gear segment assembly 20. In the preferred embodiment, the rotary motor 32 always turns in a clockwise direction.
Micro switches 84 and 86 are used to detect the rotation of the gear segment assembly 20. In the preferred embodiment, these switches allow the System Software to detect: (i) when the user starts to rotate the manual knob 14, (ii) when the user completes the 180° rotation and the lock is open, (iii) if the manual knob is partially turned but not turned sufficiently to completely open the lock, (iv) when the lock is closed and locked, (v) and if the lock drive shaft is turned and the keypad was not used (i.e., if the manual override key was used).
To validate a passcode, the microcontroller 78 accesses the database files to determine valid user codes and any rules and data values that have been applied or placed into effect for the electronic lock. For example, the lock may be set to be opened only for a specified period of time, during a limited time, during certain days. In some embodiments, other limitations and rules may be programmed into the System Software and the microcontroller 78.
The optional behaviors of the lock during the opening and closing process may be programmed for control by rules and data values entered into the System Software. For example an optional audible sound may be given for success messages and failure messages. In another example, a prescribed security time lockout may be activated if a passcode is incorrectly entered a specified number of times (for example, 3 incorrect entries).
Preferably, the System Software also records the user information, date and time when the lock was opened, failed attempts to open the lock, and the date and time that the lock was locked. Preferably time is recorded in Standard UNIX Time.
In the USB Connect Mode, a standard USB to USB Micro-A cable (not shown) is first inserted into a laptop or other computer (also not shown) and the Micro-A connection is inserted into the USB port 17 in the electronic lock. The charging circuitry of the lock will activate and begin to charge the LIPO Battery.
After successfully entering the Master Passcode, the user enters predetermined commands, for example, ‘11’ then followed by ‘P’, to activate data accessibility across the USB port. Preferably, a colored light (for example, yellow indicator light) will glow steadily when the USB data access mode has been enabled. The electronic lock's Database will show up on the computer as a mass storage drive, similar to the files presented on a USB memory stick. The user would then be able to access and copy the files onto the computer or open them with an application on the computer (e.g., Microsoft XL). Once finished, the Master User will then enter predetermined commands such as ‘11’ and then ‘P’, to disable the USB data access mode and the colored indicator light will turn off.
In the USB Host Mode, a standard USB memory stick (not shown) is connected to the USB port 17 with a USB to USB Micro-A connector cable (not shown). After entering the Master Passcode, the user enters predetermined commands ‘13’ and then ‘P’ to activate the USB port and the yellow indicator light will glow steadily. A green indicator light flashes as the database files are copied to the USB memory stick. The Master User then enters predetermined commands, such as ‘13’ and then ‘P’, to disable the USB data access connection and the yellow indicator light turns off. The user would be able to copy the files from the USB memory stick (not shown) onto the computer (also not shown) or open them with an application on the computer (for example, Microsoft XL).
Preferably, the USB Connect Mode also allows a user, such as the Master User, upload a file containing “user privileges” (a “user privileges file”) to be uploaded from a computer (not shown) connected through the USB port 17. After the Master User successfully enters the Master Passcode, the user enters predetermined commands, such as ‘14’ and then ‘P’, to activate the USB port 17 in write mode. The yellow indicator light will then glow steadily when the USB mode has been enabled. The lock Database will show up on the computer as a mass storage drive, similar to the manner in which files are listed and presented on a USB memory stick. The user may then copy the user privileges file from the computer to the electronic lock drive. Preferably, a second indicator light, such as a green light, flashes as the user privileges file is being coped to the electronic lock drive. The Master User then enters the associated predetermined codes, such as ‘14’ and then ‘P’, to disable the USB mode and the yellow indicator light turns off.
In the preferred embodiment, the RFID antenna may be made of a 2D coil design for a 125 kHz RFID antenna and made of printed copper onto a custom designed footprint and whose capacitor has been tuned so the read frequency is optimized to support 125 kHz RFID tags placed in close proximity to the keypad.
Preferably, the System Software supports the following RFID functions: (1) enable or disable optional RFID mode; (2) add or remove one or more RFID Tags; (3) Activate RFID mode once this function has been enabled and (4) Read RFID Tag.
Preferably, a Master User may enable the RFID mode by entering the programming mode as described above and then entering a corresponding predetermined command such as “20 P”. Once the appropriate command has been accepted, RFID tags can be added. This is performed by entering another predetermined command such as “21P”, followed by the step of bringing the valid RFID card or tag within proximity, typically within a few centimeters of the antenna. An indicator light, such as a green light, and an audible success sound may be programmed to notify the user if the RFID tag has been added.
Once the RFID mode is enabled and the RFID tag has been successfully added, the user having this tag may open the electronic lock by bringing the RFID tag within range of the keypad. To do this, the user will first push a predetermined command, such as the Enter button, to activate the RFID mode and then bring the tag within close proximity to the electronic lock. If the RFID tag is successfully validated, an indicator light, such as a green light and an audible success sound, will be returned and the user will be allowed to rotate the manual knob, as described more fully above, to operate the lock. Optionally, the RFID function may operate in low power mode to listen for RFID tag signal(s). This may eliminate the need for the user to press a key to reactivate the system. Once the RFID tag comes close to the antenna (e.g. within a few centimeters) the presence of an RFID tag first wakes up the system and then RFID tag is read.
NFC-enabled devices can act as electronic identity documents or keycards. As NFC has a short range and supports encryption, it may be more suitable than earlier, less secure RFID systems.
NFC is a set of short-range wireless technologies, typically requiring a distance of 4 cm or less. NFC operates at 13.56 MHz on ISO/IEC 18000-3 air interface and at rates ranging from 106 KBS to 424 KBS.
Preferably, the electronic lock is the initiator which actively generates an RF field that can power a passive target. The NFC targets to take very simple form factors such as tags, stickers, key fobs, or cards that do not require batteries. NFC Targets may also include a variety of NFC-enabled smartphones including selected models of Google Nexus, Samsung Galaxy, RIM Blackberry, Apple IPhone, and many other examples of smartphones.
The operation of the electronic lock with passive NFC targets such as key fobs and cards is similar to the RFID mode as described above. Operation of the lock may also be performed from NFC-enabled smartphones in either of two modes: (i) Smart card-emulation mode allows the emulation of a contactless smart card or (ii) a Dedicated System Application saved on the smartphone which is enabled to transmit encrypted codes in a peer-to-peer mode between the smartphone and the RFID/NFC features provided on the electronic lock.
In the preferred embodiment, the System Software supports the following NFC functions: (1) enable or disable optional NFC mode; (2) Add or remove one or more NFC Targets; (3) Activate NFC mode once this function has been enabled and (4) Read NFC Tag.
In a preferred embodiment, the electronic lock is shipped with preloaded software and other information such as a unique internal serial number dedicated to each electronic lock. In the event that the Master Codes are lost for a particular device, the preferred electronic lock is provided with a secure preloaded program to execute a factory reset. This process will restore all of the lock defaults and set the master password to a known number. The preferred System Software may contain an encryption algorithm so that a unique factory reset code may be issued for each unique electronic lock Serial Number. In addition, the preloaded program may provide that this unique reset code will only be accepted by the specific electronic lock having the correct, corresponding Serial Number. The reset code may be programmed to be valid for a limited period of time as specified by the manufacturer.
An encryption algorithm may also provide a secure code combination for daily use of the lock. For example, this feature could be utilized in corporate hoteling uses where visiting employees could periodically use a free desk for a day. It could also be used for a day locker in public areas. A computer application may be provided to generate an encrypted code that would work for a specific time period or until the code is changed. The computer application may be synchronized with a specific lock so that the code will be unique to that lock.
Persons skilled in the art will appreciate that the foregoing descriptions were directed to specific embodiments of the invention. However, many other variations and modifications of the invention are also possible. Several preferred embodiments of the invention have been described with regard to the appended drawings. It will be apparent to those skilled in the art that additional embodiments are possible and that such embodiments will fall within the scope of the appended claims.
Prior Art
| Number | Name | Date | Kind |
|---|---|---|---|
| 3901542 | Salzman et al. | Aug 1975 | A |
| 4213118 | Genest et al. | Jul 1980 | A |
| 4712398 | Clarkson et al. | Dec 1987 | A |
| 4745784 | Gartner | May 1988 | A |
| 4760380 | Quenneville et al. | Jul 1988 | A |
| 4789859 | Clarkson et al. | Dec 1988 | A |
| 4887445 | Beatty | Dec 1989 | A |
| 4901545 | Bacon et al. | Feb 1990 | A |
| 4931789 | Pinnow | Jun 1990 | A |
| 4967305 | Murrer et al. | Oct 1990 | A |
| 5020345 | Gartner et al. | Jun 1991 | A |
| 5021776 | Anderson et al. | Jun 1991 | A |
| 5033282 | Gartner et al. | Jul 1991 | A |
| 5058258 | Harvey | Oct 1991 | A |
| 5136870 | Gartner et al. | Aug 1992 | A |
| 5153561 | Johnson | Oct 1992 | A |
| 5223829 | Watabe | Jun 1993 | A |
| 5265452 | Dawson et al. | Nov 1993 | A |
| 5321963 | Goldman | Jun 1994 | A |
| 5367295 | Gokcebay et al. | Nov 1994 | A |
| 5437174 | Aydin et al. | Aug 1995 | A |
| 5475375 | Barrett et al. | Dec 1995 | A |
| 5479151 | Lavelle et al. | Dec 1995 | A |
| 5507162 | Chhatwal | Apr 1996 | A |
| 5552777 | Gokcebay et al. | Sep 1996 | A |
| 5636880 | Miller | Jun 1997 | A |
| 5685182 | Chhatwal | Nov 1997 | A |
| 5749253 | Glick et al. | May 1998 | A |
| 5816084 | Clark | Oct 1998 | A |
| 5823027 | Glick et al. | Oct 1998 | A |
| 5848541 | Glick et al. | Dec 1998 | A |
| 5857365 | Armstrong | Jan 1999 | A |
| 5886644 | Keskin et al. | Mar 1999 | A |
| 5887467 | Butterweck et al. | Mar 1999 | A |
| 5894277 | Keskin et al. | Apr 1999 | A |
| 6000609 | Gokcebay | Dec 1999 | A |
| 6016677 | Clark | Jan 2000 | A |
| 6032500 | Collard, Jr. et al. | Mar 2000 | A |
| 6092404 | Chhatwal | Jul 2000 | A |
| 6098433 | Maniaci | Aug 2000 | A |
| 6116067 | Myers et al. | Sep 2000 | A |
| D438447 | Gartner | Mar 2001 | S |
| 6209367 | Hyatt, Jr. et al. | Apr 2001 | B1 |
| 6244084 | Warmack | Jun 2001 | B1 |
| 6297725 | Tischendorf et al. | Oct 2001 | B1 |
| 6318137 | Chaum | Nov 2001 | B1 |
| D452807 | Gartner | Jan 2002 | S |
| 6374653 | Gokcebay et al. | Apr 2002 | B1 |
| 6384711 | Cregger et al. | May 2002 | B1 |
| 6434987 | Juillerat et al. | Aug 2002 | B1 |
| 6487884 | Constantinou | Dec 2002 | B1 |
| 6552650 | Gokcebay et al. | Apr 2003 | B1 |
| 6564601 | Hyatt Jr. | May 2003 | B2 |
| 6588243 | Hyatt, Jr. et al. | Jul 2003 | B1 |
| D484390 | Abernethy et al. | Dec 2003 | S |
| 6655180 | Gokcebay et al. | Dec 2003 | B2 |
| 6722167 | Hsu | Apr 2004 | B1 |
| 6730867 | Hyp | May 2004 | B2 |
| 6739164 | Warmack | May 2004 | B2 |
| 6745603 | Shaw | Jun 2004 | B1 |
| 6760964 | Gartner | Jul 2004 | B1 |
| 6826935 | Gokcebay et al. | Dec 2004 | B2 |
| D501388 | Carpintero | Feb 2005 | S |
| 6865916 | Goldman | Mar 2005 | B2 |
| 6876293 | Frolov et al. | Apr 2005 | B2 |
| 6891458 | Hyatt, Jr. et al. | May 2005 | B2 |
| 6895791 | Alexander et al. | May 2005 | B2 |
| 6926318 | Oxley | Aug 2005 | B2 |
| 6927670 | Gokcebay et al. | Aug 2005 | B1 |
| 6967562 | Menard et al. | Nov 2005 | B2 |
| D512297 | Metivier et al. | Dec 2005 | S |
| 7010947 | Milo | Mar 2006 | B2 |
| D520848 | Metivier et al. | May 2006 | S |
| 7144053 | Bashford | Dec 2006 | B2 |
| 7209029 | Coelho et al. | Apr 2007 | B2 |
| 7221272 | Hosselet | May 2007 | B2 |
| 7296448 | Shaw | Nov 2007 | B1 |
| 7316139 | Nakazima et al. | Jan 2008 | B2 |
| 7334443 | Meekma et al. | Feb 2008 | B2 |
| 7336150 | Gokcebay et al. | Feb 2008 | B2 |
| 7397343 | Gokcebay et al. | Jul 2008 | B1 |
| D580837 | Kluck | Nov 2008 | S |
| 7469564 | Shaw | Dec 2008 | B1 |
| 7472934 | Burke et al. | Jan 2009 | B2 |
| 7516633 | Chang | Apr 2009 | B1 |
| D593398 | Pelletier et al. | Jun 2009 | S |
| 7637131 | Amir | Dec 2009 | B2 |
| 7647797 | Viso Cabrera et al. | Jan 2010 | B1 |
| 7747286 | Conforti | Jun 2010 | B2 |
| 7768378 | Hill et al. | Aug 2010 | B2 |
| 7770423 | Wu | Aug 2010 | B2 |
| 7845202 | Padilla et al. | Dec 2010 | B2 |
| 7870770 | Blanch | Jan 2011 | B2 |
| 7891222 | Ratkus et al. | Feb 2011 | B2 |
| 8035478 | Lee | Oct 2011 | B2 |
| 8122746 | Hyatt, Jr. | Feb 2012 | B2 |
| 8141399 | Hyatt, Jr. | Mar 2012 | B2 |
| 8141400 | Sorensen et al. | Mar 2012 | B2 |
| 8161781 | Gokcebay | Apr 2012 | B2 |
| 8176761 | Sorensen et al. | May 2012 | B2 |
| 8228030 | Pukari et al. | Jul 2012 | B2 |
| 8276414 | Luo | Oct 2012 | B2 |
| 8468861 | Pukari et al. | Jun 2013 | B2 |
| 8490443 | Gokcebay | Jul 2013 | B2 |
| 8495898 | Gokcebay | Jul 2013 | B2 |
| 8495899 | Gartner | Jul 2013 | B2 |
| 8528373 | Hyatt, Jr. et al. | Sep 2013 | B2 |
| 8683832 | Watanabe et al. | Apr 2014 | B2 |
| 8742889 | Kaczmarz et al. | Jun 2014 | B2 |
| 8866439 | Pukari et al. | Oct 2014 | B2 |
| 8869574 | Schmidt-Lackner et al. | Oct 2014 | B2 |
| 8902040 | Greisen et al. | Dec 2014 | B2 |
| 8970344 | Payson et al. | Mar 2015 | B2 |
| 9208628 | Gokcebay | Dec 2015 | B2 |
| 9222284 | Gokcebay | Dec 2015 | B2 |
| 20010005998 | Imedio Ocana | Jul 2001 | A1 |
| 20010045112 | Berton et al. | Nov 2001 | A1 |
| 20020056300 | Pierre et al. | May 2002 | A1 |
| 20020125992 | Harwood | Sep 2002 | A1 |
| 20040003633 | Alexander et al. | Jan 2004 | A1 |
| 20040177660 | Tsai | Sep 2004 | A1 |
| 20050128050 | Frolov et al. | Jun 2005 | A1 |
| 20050179517 | Harms et al. | Aug 2005 | A1 |
| 20050199026 | Geringer et al. | Sep 2005 | A1 |
| 20050253715 | Awobue | Nov 2005 | A1 |
| 20060226948 | Wright et al. | Oct 2006 | A1 |
| 20060238294 | Gokcebay et al. | Oct 2006 | A1 |
| 20060283216 | Marcelle et al. | Dec 2006 | A1 |
| 20070169525 | Chang | Jul 2007 | A1 |
| 20070209413 | Dobbs | Sep 2007 | A1 |
| 20070257773 | Hill et al. | Nov 2007 | A1 |
| 20080084836 | Baird et al. | Apr 2008 | A1 |
| 20080223093 | Amir | Sep 2008 | A1 |
| 20080252083 | Carabalona | Oct 2008 | A1 |
| 20080296912 | Whitner et al. | Dec 2008 | A1 |
| 20090058102 | Garneau et al. | Mar 2009 | A1 |
| 20090085717 | Kirkjan | Apr 2009 | A1 |
| 20100073129 | Pukari | Mar 2010 | A1 |
| 20100079240 | Higham | Apr 2010 | A1 |
| 20100300163 | Loughlin et al. | Dec 2010 | A1 |
| 20100307206 | Taylor et al. | Dec 2010 | A1 |
| 20100320971 | Zhu et al. | Dec 2010 | A1 |
| 20110012709 | Payson et al. | Jan 2011 | A1 |
| 20110056253 | Greiner et al. | Mar 2011 | A1 |
| 20110181060 | Geringer et al. | Jul 2011 | A1 |
| 20130043973 | Greisen et al. | Feb 2013 | A1 |
| 20130298618 | Gotter | Nov 2013 | A1 |
| 20140047878 | Zheng et al. | Feb 2014 | A1 |
| 20150211258 | Gokcebay | Jul 2015 | A1 |
| Number | Date | Country |
|---|---|---|
| 2388230 | Nov 2003 | CA |
| 2450509 | May 2012 | EP |
| 0186097 | Nov 2001 | WO |
| 2005017293 | Feb 2005 | WO |
| 2006114330 | Nov 2006 | WO |
| 2006114330 | Nov 2006 | WO |
| 2007000576 | Jan 2007 | WO |
| 2010124851 | Nov 2010 | WO |
| 2011160628 | Dec 2011 | WO |
| Entry |
|---|
| Theodore Ullrich et al., U.S. Appl. No. 13/468,240, filed May 10, 2012. |
| Notice of Allowance U.S. Appl. No. 13/468,240 dated Sep. 9, 2013. |
| MicroIQ Lock, MicroIQ, http://microiqlock.com/, last visited Nov. 17, 2016. |
| Codelocks CL2255-BS Electronic Tubular Mortise-Style Keypad Door Lock, Smarthome, http://www.smarthome.com/codelocks-cl2255-bs-electronic-tubular-mortise-style-keypad-door-lock-brushed-steel.html, last visited Nov. 17, 2016. |
| Lockey M210, GoKeyless, http://www.gokeyless.com/product/43/lockey-m210-keyless-deadbolt, last visited Oct. 11, 2016. |
| Codelocks KL 1200 Heavy Duty Push Button Electronic Cabinet Lock, American Builders Outlet, http://www.americanbuildersoutlet.com/codelocks-cl1200-heavy-duty-push-button-electronic-cabinet-lock.html, last visited Oct. 11, 2016. |
| Entry Check TM 923 Narrow Series Digital Keypads, Security Door Controls, http://www.sdcsecurity.com/newproducts.htm, last visited Oct. 11, 2016. |
| Schlage Sense Smart Deadbolt with Century Trim in Satin Nickel (BE479 CEN 619), Amazon, http://www.amazon.com/dp/B00YUPDUYE?psc=1, last visited Oct. 18, 2016. |
| Two-Point Electronic Lock Retrofit Kit, System 1000, Chatsworth Products, https://catalog.chatsworth.com/environmental-monitoring-security/electronic-locks/two-point-electronic-lock-retrofit-kit-system-1000, last visited Oct. 11, 2016. |
| KL 1000 Kitlock Locker Lock, Codelocks, http://www.codelocks.us/kitlock/kl1000-kitlock-locker-lock.html, last visited Oct. 19, 2016. |
| Browning S&G Retrofit Electronic Lock Kit #156022, Amazon Sports & Outdoors, http://www.amazon.com/Browning-Retrofit-Electronic-Lock-156022/dp/B000PW45C2, last visited Oct. 11, 2016. |
| Electronic Door Access, Locking Systems, http://www.lockingsystems.com/electronicdooraccess.htm, last visited Oct. 18, 2016. |
| Push Button Mechanical Lock, Ningbo Yosec Industrial, http://safes-china.en.hisupplier.com/product-1133779-pushbutton-mechanical-lock.html, last visited Nov. 17, 2016. |
| Number | Date | Country | |
|---|---|---|---|
| 20130298616 A1 | Nov 2013 | US |
