Abstract:
A door frame has a first electromagnetic coil and a door lock has a second electromagnetic coil with a door bolt electromagnetically coupling together the first and second electromagnetic coils, thereby forming a transformer. Power is transferred from the door frame to door lock through the transformer. Communications from the door frame to the door lock may be provided by modulating electromagnetic energy to the first electromagnetic coil and demodulating the modulated electromagnetic energy received at the second electromagnetic coil. Communications from the door lock to the door frame may be provided by varying a load on the second electromagnetic coil and detecting the load change at the first electromagnetic coil.

Description:
RELATED PATENT APPLICATION 
       [0001]    This application claims priority to commonly owned U.S. Provisional Patent Application No. 61/824,248 filed May 16, 2013, is hereby incorporated by reference herein for all purposes. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates to door lock systems, and, in particular, to a wireless door lock power transfer system having communications capabilities therewith. 
       BACKGROUND 
       [0003]    Recent trends are increasing the intelligence of door locks through electronic means. Most vendors use battery power for the electronics associated with these intelligent door locks. However, this application has problems with battery life. Alternative door lock powering systems use armored cable to supply power to the door lock electronics. This solution requires custom, complicated and expensive modifications to the door. 
       SUMMARY 
       [0004]    Therefore a need exists for an improved door lock power transfer system, and in particular for a wireless door lock power transfer system having communications capabilities therewith. 
         [0005]    According to an embodiment, an apparatus for transferring power wirelessly to a door lock may comprise: a first electric inductor shaped as a coil, adapted to receive a first portion of a door locking bolt and installed in a door frame; a power transmitter having an alternating current (AC) output coupled to the first electric inductor and an input coupled to a first power source; a second electric inductor shaped as a coil that surrounds the door locking bolt and may be installed in a door; and a power receiver having an input coupled to the second electric inductor and an output for providing a second power source. 
         [0006]    According to a further embodiment, a power storage device may be coupled to the output of the power receiver. According to a further embodiment, the power storage device may be a rechargeable battery. According to a further embodiment, the power storage device may be a super capacitor. According to a further embodiment, a door frame transceiver and a door transceiver may be provided for communicating between the door frame and the door. 
         [0007]    According to a further embodiment, wherein: the door frame transceiver may be coupled to the power transmitter and modulates the AC output thereof for reception by the door transceiver through the second inductor; and the door transceiver may be coupled to the power receiver, wherein the power receiver modulates a load on the second inductor that may be detected by the door frame transceiver through the first inductor. According to a further embodiment, the door frame and door transceivers communicate with at least one wireless signal conveying data therebetween. According to a further embodiment, the wireless signal may be selected from the group consisting of Bluetooth®, Wi-Fi®, ZigBee®, IRDA, InfraRed, and Ultrasonic. According to a further embodiment, the wireless signal may be formatted in accordance with at least one communications standard selected from the group consisting of Bluetooth®, Wi-Fi®, and Zigbee®. 
         [0008]    According to a further embodiment, a door frame digital processor may be coupled to the door frame transceiver and the power transmitter, and a door digital processor may be coupled to the door transceiver and the power receiver. According to a further embodiment, the bolt may be selected from the group consisting of a magnetic metal, a plurality of magnetic metal plates insulated from one another, ferrite impregnated epoxy molded into a door bolt shape. According to a further embodiment, the bolt may be a quartz crystal core surrounded by a metal sleeve that resonantly couples power from the first electric inductor to the second electric conductor. According to a further embodiment, power may be transferred through capacitive coupling between the door frame and the door. According to a further embodiment, power may be transferred from the first electric inductor to the second electric conductor acting as an air core transformer. 
         [0009]    According to a further embodiment, a coded unlocking device may be coupled to the door digital processor. According to a further embodiment, the coded unlocking device may be a key card and key card reader in the door. According to a further embodiment, the coded unlocking device may be a BodyCom™ receiver coupled to a handle or knob of the door and adapted to receive a BodyCom™ signal when the handle or knob is touched by a person with a BodyCom™ transmitter having a corresponding access code for the door lock. According to a further embodiment, heat sensors may be on each side of the door, wherein the heat sensors may be coupled to the door digital processor and provide surface temperatures of each side of the door. 
         [0010]    According to a further embodiment, the door digital processor may cause a door handle or knob to vibrate if the surface temperature on the opposite side of the door may be above a certain temperature. According to a further embodiment, a door handle or knob position sensor may be coupled to the door digital processor for indicating positions of the door handle or knob. According to a further embodiment, the door unlocks to open and then relocks upon closing when the door handle or knob is rotated in a first direction, and the door unlocks to open and remains unlocked upon closing when the door handle or knob is rotated in a second direction. According to a further embodiment, the door unlocks when the door handle or knob is rotated in a correct sequential combination of positions and directions. According to a further embodiment, the door frame and door digital processors may be microcontrollers. 
         [0011]    According to another embodiment, a wireless door lock power transfer system may comprise: a first circuit arranged within a door frame and that may comprise: a first coil, a power driver coupled with the first coil operable to transmit power and to transmit and receive data via said first coil, and a first microcontroller coupled with said power driver; and a second circuit arranged within a door and that may comprise: a bolt operable to engage with said door frame and further operable to be received within said first coil when engaging with said door frame, a second coil surrounding said bolt on a door side, a receiving unit coupled with said second coil operable to receive power and to receive and transmit data via said second coil, and a second microcontroller coupled with said receiving unit, wherein the receiving unit provides a supply voltage to said second microcontroller when said second coil receives a carrier signal transmitted by said first coil via said bolt. 
         [0012]    According to a further embodiment, the second circuit may comprise a high power voltage supply system controlled by said second microcontroller for providing a high power supply voltage. According to a further embodiment, the second circuit further comprises a driving unit operable to move said bolt into and output of said door frame for locking and unlocking said door, wherein the driving unit may be coupled with said high power supply voltage system. According to a further embodiment, a plurality of bolts may be provided at a plurality of locations around said door proximate to said door frame and operable to move said plurality of bolts. According to a further embodiment, the high power voltage supply system may be a switched mode power supply controlled by said second microcontroller. According to a further embodiment, the receiving unit modulates loading of said second coil for transmitting data from said second circuit to said first circuit. According to a further embodiment, the power driver may modulate the transmitted power to said first coil for transmitting data from said first circuit to said second circuit. 
         [0013]    According to yet another embodiment, a method for transferring power wirelessly to a door lock may comprise the step of: transmitting electromagnetic energy from a power transmitter proximate to a door frame through, a door bolt to a power receiver in a door, the power transmitter may be coupled to a first electromagnetic coil surrounding a first portion of the door bolt and the power receiver may be coupled to a second electromagnetic coil surrounding a second portion of the door bolt. 
         [0014]    According to a further embodiment of the method, the step of communicating between the door frame and door may comprise the step of communicating through the power transmitter and the power receiver. According to a further embodiment of the method, the step of communicating through the power transmitter and the power receiver may comprise the steps of: modulating the electromagnetic energy with the power transmitter; demodulating the electromagnetic energy with the power receiver; varying a load coupled to the second electromagnetic coil with the power receiver; and detecting variations of the load coupled between the second and first electromagnetic coils with the power transmitter. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    A more complete understanding of the present disclosure may be acquired by referring to the following description taken in conjunction with the accompanying drawings wherein: 
           [0016]      FIG. 1  illustrates a schematic block diagram of a door lock power transfer system having communications capabilities therewith, according to a specific example embodiment of this disclosure; 
           [0017]      FIG. 2  illustrates a more detailed schematic block diagram of a door lock power transfer system having communications capabilities therewith, according to a specific example embodiment of this disclosure; 
           [0018]      FIG. 3  illustrates a schematic diagram of a capable haptic door lever/knob at several different positions, according to another specific example embodiment of this disclosure; and 
           [0019]      FIG. 4  illustrates a schematic diagram of a BodyCom™ activated security door entry system, according to still another specific example embodiment of this disclosure. 
       
    
    
       [0020]    While the present disclosure is susceptible to various modifications and alternative forms, specific example embodiments thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific example embodiments is not intended to limit the disclosure to the particular forms disclosed herein, but on the contrary, this disclosure is to cover all modifications and equivalents as defined by the appended claims. 
       DETAILED DESCRIPTION 
       [0021]    According to various embodiments, powering and communicating to door locking mechanisms without the reliability and expense issues associated with batteries or hard wiring can be provided. According to various embodiments, a power transfer system is proposed that uses the lock bolt as the core of a transformer having a first electrical inductive coil winding in the door frame and over a first portion of the lock bolt, and a second electrical inductive coil winding in the door and over a second portion of the lock bolt. This transformer couples power from a door frame power source to the lock apparatus, and also may have the capability to be used for communications between the door lock apparatus and the associated door frame apparatus. 
         [0022]    Thus, no issues with dead batteries can occur. No expensive armored cables are need. No custom door modifications are necessary. The power transfer system, according to the teachings of this disclosure, may be capable of coupling higher power and bidirectional data, and, addition, has the potential to transmit sufficient power for electro-mechanically mechanical elements of a door locking assembly, e.g., door bolt, door latch, locking tumblers, etc. 
         [0023]    Referring now to the drawings, the details of example embodiments are schematically illustrated. Like elements in the drawings will be represented by like numbers, and similar elements will be represented by like numbers with a different lower case letter suffix. 
         [0024]    Referring to  FIG. 1 , depicted is a schematic block diagram of a door lock power transfer system having communications capabilities therewith, according to a specific example embodiment of this disclosure. The power transfer system having communications capabilities therewith may be divided into two parts: (1) lock bolt receiving, e.g., striker plate  116 ; power generation and communications apparatus in the door frame  102 ; and (2) a locking apparatus comprising power receiving and storage, communications, a lock bolt and lock bolt control in the door  104 . In the door frame  102 , a first power circuit may comprise an inductive driver power transmitter  110  coupled to a first inductive coil  114  that surrounds a first portion of a movable lock bolt  120  from the door  104 . The inductive driver power transmitter  110  and first inductive coil  114  generate an alternating current (AC) magnetic field in the lock bolt  120 . 
         [0025]    In the locking apparatus within the door  104  a second power circuit may comprise a second inductive coil  118  surrounding a second portion of the movable lock bolt  120 . The lock bolt  120  functions as the core of a transformer, thereby efficiently transferring magnetic flux between the first and second inductive coils  114  and  118 . This magnetic flux transfer causes the second inductive coil  118  to generate an alternating current (AC) voltage that may be converted to a direct current (DC) voltage in the power receiver  126 . This converted (rectified) DC voltage may be stored in a power storage/source device  128 , e.g., battery or super capacitor, and/or used directly to power high energy requirement components of the door lock, e.g., electro-mechanical actuation of the lock bolt  120  opening and/or closing. The power storage/source device  128  may power a door digital processor  124  and a door communications transceiver  122 . 
         [0026]    The door frame and door communications transceivers  106  and  122  may be coupled to and communicate through their respective first and second inductive coils  114  and  118 . These communications couplings may be direct to the respective inductive coils but preferably may be through the power transmitter  110  and power receiver  126  by modulating the magnetic flux, e.g., changing the amplitude, phase and/or frequency of the AC voltage from the power transmitter  110  and altering the magnetic flux field by changing the load (impedance) of the second inductive coil  118  with the power receiver  126 . Thus, two way communications may be established between the door frame  102  and the door  104 . Alternately or in addition to the magnetic flux induced communications through the bolt  120 , a wireless signal(s)  130  may be used directly between the door and door frame transceivers  122  and  106 , e.g., Bluetooth® a registered trademark owned by the Bluetooth® SIG, Wi-Fi® a registered trademark owned by the Wi-Fi Alliance, ZigBee® a registered trademark owned by the ZigBee Alliance, IRDA, InfraRed, Ultrasonic; or any other radio frequency, optic or audio based communications system. Wireless signal(s)  130  may be advantageously used when the door  104  is open and the bolt  120  is not in or proximate to the first inductive coil  114 . The same wireless signal  130  or other wireless signal(s) may be used in a communications network to send and receive data between a plurality of doors  104 /door frames  102  and a central control computer (not shown) for control and monitoring of each door  104  and/or door frame  102 . Central monitoring control may comprise, but is not limited to, remotely changing security entry codes, locking and unlocking doors  104  by remotely controlling a bolt locking mechanism (not shown) or electro-mechanically moving the bolt  120  in or out of the door frame  102  striker plate  116 . The communications network may be, for example but is not limited to, Wi-Fi®, ZigBee®, IOT (Internet of things), node-to-node communications, or networked communications system having a standard or custom protocol. Monitoring may comprise, but is not limited to, bolt position (door locked or unlocked), door open or closed, temperatures of each side of door (fire monitoring conditions), security camera imbedded in outside (hall facing) surface of door  104 . 
         [0027]    A door digital processor  124  may be used to control functions of locking and bolt actuation, data communications via the door transceiver  122 , and security code storage and comparison to a security entry device, e.g., magnetic card, wireless key fob, voice recognition, fingerprint recognition, facial recognition, iris scan, keypad entry code, RFID security badge, BodyCom™ (a pending trademark application owned by Microchip Technologies Incorporated), transmitted encrypted entry code, palm scanner, magnetic key, combination lock using unique door position combinations, or 2D bar code on ID badge. Not shown is a key card reader or key pad that may be coupled to the door digital processor  124  and used to unlock the bolt  120  and gain access to a room behind the door  104  when the key card security code matches the security code stored in the door digital processor  124 . It is within the scope of this disclosure that other forms of security access are contemplated as more fully described hereinafter. The bolt  120  may be unlocked with deactivation (withdrawal) of a locking pin (not shown) and the bolt mechanically moved to a retracted position within the door  104  by a door handle or knob (not shown), or electro-mechanically moved from an extended position in the door frame  102 /striker  116  to a retracted position within the door  104 . A door frame digital processor  108  may be used to control functions of a door frame transceiver  106  and power transmitter  110 . The power source  112  may be from a local 120 VAC branch circuit (not shown), e.g., through a power transformer (not shown) connected to a room outlet and coupled to a power jack (not shown) in the door frame  102 . The door and/or door frame digital processors  124  and/or  108  may be part of respective microcontrollers in the lock of the door  104  and door frame  102 . The door bolt  120  may comprise, for example but is not limited to, solid metal having magnetic properties, laminated and insulated strips of magnetic metals such as used in power transformers, a solid ferrite rod of magnetic material that may be easily molded, e.g., ferrite particles in an epoxy resin base. Power transfer may also be provided through capacitive coupling through high permittivity material, resonantly coupled through a quartz crystal core surrounded by a metal sleeve, and/or open air coupled e.g., air core transformer like keycards. 
         [0028]    Referring to  FIG. 2 , depicted is a more detailed schematic block diagram of a door lock power transfer system having communications capabilities therewith, according to a specific example embodiment of this disclosure. In the door frame  102 , an Inductive Sensor Analog Front End Device model MCP2036, manufactured by Applicant, may provide the power transmitter  110  and door frame communications transceiver  106  functions as shown in  FIG. 1 . A microcontroller model PIC16F182X, manufactured by Applicant, may provide the door frame digital processor  108  functions as shown in  FIG. 1 . In the door  104 , a Three-Channel Analog Front-End Device model MCP2030, manufactured by Applicant, may provide the power receiver  126  and door communications transceiver  122  functions as shown in  FIG. 1 . Any microcontroller having a USART and pulse width modulation control capabilities may provide the door digital processor  124  functions as shown in  FIG. 1 . A switch mode power supply  128  may be used to provide higher voltage/power for operation of an electro-mechanical actuator for movement of the door bolt  120 . Data sheets and Applications Notes for the aforementioned devices are available at www.microchip.com, and are hereby incorporated by reference herein for all purposes. 
         [0029]    The MCP2036 ( 106 ,  110 ) coupled to and in combination with the first inductive coil  114  may be used to generate an AC magnetic field in the bolt  120  of the lock. In the lock within the door  104 , the integrated analog front end device MCP2030 ( 122 ,  126 ) receives an AC voltage from the second inductive coil  118  and converts this AC voltage to a DC voltage. 
         [0030]    The MCP2036 ( 106 ,  110 ) has a clock that may be driven by a data signal modulator (DSM) in the associated microcontroller  108 . The DSM can modulate the AC magnetic field allowing the transmission of data to the lock electronics within the door, where it may be decoded, for example, by the analog front end device MCP2030 ( 122 ,  126 ). 
         [0031]    Data can also be passed from the lock electronics within the door to the frame electronics, for example, by the analog front end device MCP2030 ( 122 ,  126 ) that may modulate the load of the second inductive coil  118  of the transformer formed by the first and second inductive coils  114  and  118 , and the bolt  120 . Wherein the MCP2036 ( 106 ,  110 ) detects the change in load as a change in the impedance of the secondary of the transformer and then passes this to a comparator for conversion to a digital level that may be decoded by a USART in the microcontroller  108 . 
         [0032]    It should be noted that the impedance detection within the MCP2036 also may provide an indication of whether the bolt  120  is present in the first inductive coil  114  and hence if the door is closed and locked. A lower inductive impedance detection may show that the door is closed but not locked where the bolt  120  is proximate to but not in the first inductive coil  114 . Detection of the lowest impedance would indicate that the door is open and the bolt  120  is not proximate to the first inductive coil  114 . 
         [0033]    According to some embodiments, other modulation schemes may be used. For example, the first circuit in the door lock may use a carrier frequency different from the carrier frequency of the second circuit in the frame and modulate it with frequency or amplitude modulation. Other modulation techniques may be used and are contemplated herein for all purposes. 
         [0034]    The MCP2036 was originally designed for use with inductive touch systems, and while the MCP2030 was designed for passing data in this form, it was designed for communicating with passive very low-power identity cards. The use of the bolt  120  as a magnetic core allows however the transfer of much higher power levels as well as providing an indication of the door closure/locked or unlocked, and door open. 
         [0035]    The system part arranged within the door may comprise a microcontroller  124  having an asynchronous transceiver, a pulse width modulation (PWM) unit, a voltage comparator and a reference voltage source as shown in  FIG. 2 . The comparator, voltage reference and pulse width modulator are used to generate an internal high power supply voltage using switched mode power supply techniques. The high power voltage may be used directly to operate the bolt  120 , for example by a motor, a servo or solenoid magnet. 
         [0036]    The basic supply voltage Vdoor may be generated by the MCP2030 which is operable to convert a carrier frequency received from the coil  118  arranged around the bolt  120  into a supply voltage. The carrier frequency is furthermore modulated to transmit data from the door frame  102  to the door system parts as shown. Furthermore, the MCP2030 is operable to modulate the received carrier frequency, for example by modulating a load applied to the receiving inductive coil  118 . Thus, the transmitter side in the door frame  102  can detect the loading thereof and convert it into a data stream for receiving data from the door  104 . 
         [0037]    The door frame side also comprises a microcontroller  108 , here, for example but not limited to, a microcontroller from the PIC16F182X family manufactured by Applicant. The MCP2036 which is generally designed for an inductive proximity detection system may be used as a driver circuit for transmitting power and data as shown. The microcontroller used in this embodiment thus only requires a digital signal modulator and a comparator which may be coupled with an asynchronous peripheral in the transceiver  106 . 
         [0038]    Referring to  FIG. 3 , depicted is a schematic diagram of a haptic capable door lever/knob at several different positions, according to another specific example embodiment of this disclosure. As shown in  FIG. 3(   a ), a door handle  340  or knob (not shown) may be adapted to be positioned in a plurality of rotational orientations. For example, the position of the door handle  340  may signify a door locked condition with the bolt  120  extended into the door frame  102  and striker plate  116 . The position of the door handle  340   a  may signify a door open condition with the bolt  120  retracted from the door frame  102  and striker plate  116 , wherein when the door  120  is closed but the bolt  120  remains in the retracted unlocked condition. The position of the door handle  340   b  may signify a door open condition with the bolt  120  retracted from the door frame  102  and striker plate  116 , wherein when the door  120  is closed the bolt  120  returns back to the extended locked condition. It is contemplated and within the scope of this disclosure that many other door handle  340  positions may be programmed such as an emergency alert if the handle  340  is moved to the door handle  340   a  position and then to the door handle  340   b  position. Key-less and card-less unlocking of the door may also be accomplished by unique position combinations of the door handle  340 , similar to a combination safe lock. Numbers and/or letters may be placed on the door around the circumference of the shaft of the door handle  340 , e.g., as shown in  FIG. 3(   a ), for improved granularity of handle position locations to increase the number and complexity of the entry codes available. For example, move door handle  340  clockwise to position a, then counterclockwise to position e, then clockwise to position b, then counterclockwise to position d, etc. 
         [0039]    Referring to  FIG. 3(   b ), a handle position sensor  342  may be coupled to the door digital processor  124  to provide positions of the handle  340  thereto. A haptic tactile feedback generator  344  may be coupled to the handle  340 , wherein various turning resistances may be provided, e.g., to indicate locked or unlocked bolt position; and/or the door handle  340  can be made to vibrate when being rotated if there is danger on the other side of the door, e.g., fire in the room or hallway. Haptic technology or “Haptics” provides tactile feedback to the user by applying forces or vibrations. Microchip&#39;s MTCH810 is an integrated controller which allows engineers to easily add haptic features to door lock applications. More detailed information on haptics may be found at www.microchip.com and a typical Haptic Controller model MTCH810, manufactured by Applicant, may be used for such purposes. Haptic technology and the Haptic Controller model MTCH810 data sheets are incorporated by reference herein for all purposes. 
         [0040]    Referring to  FIG. 4 , depicted is a schematic diagram of a BodyCom™ activated security door entry system, according to still another specific example embodiment of this disclosure. The BodyCom™ system is a new short-range wireless connectivity technology that uses the capability of the human body to transport a few signals that provide intuitive, simple, and safe communication between two electronically compatible devices. Communication between BodyCom™ system devices occurs when they are within a few centimeters of the human body: a simple proximity or touch detection can establish a BodyCom™ system connection. More detailed information on the BodyCom™ technology is provided in Microchip Application Note AN1391 available at www.microchip.com, and is incorporated by reference herein for all purposes. 
         [0041]    A person  452  may wear a BodyCom™ security access device  450  on his or her person, e.g., wristband, waste band, ankle band, security card in wallet, necklace, secured and hidden device on person for sensitive high security situations, e.g., prisons and mental hospitals. The door lock may be configured with a BodyCom™ receiver such that when the door handle (knob)  340  is grasped by an authorized person having a properly coded BodyCom™ security access device  450 , the door will unlock and provide him or her access through the unlocked door. Without the BodyCom™ security access device  450  having proper access coding, unlocking of the door will be denied. Special access options may also be provided for police and firemen to gain access quickly through a door so equipped when they have the correct BodyCom™ security access device  450 . 
         [0042]    It is contemplated and with the scope of this disclosure that a plurality of electro-mechanically operated bolts  120  may be integrated into the door  104  with corresponding striker plates  116  and first inductive coils  114  for bolt position sensing. This type of door locking system gives added security and protection from invasion to high security areas, e.g., airplane cockpit, safe rooms, school room access, etc. It is also contemplated and with the scope of this disclosure that the door lock mechanism may be remotely set to either an unlocked or locked condition during situations that warrant such actions, e.g., unlock all doors during a fire alert, lock all doors during a prison riot, etc. 
         [0043]    In summary, the proposed solution solves the power problem, provides secure communications, provides for door lock position detection, and adds new levels of security and access to electronically operated door locks. 
         [0044]    While embodiments of this disclosure have been depicted, described, and are defined by reference to example embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those ordinarily skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and are not exhaustive of the scope of the disclosure.