Patent Publication Number: US-2020291683-A1

Title: Electromechanical lock utilizing magnetic field forces

Description:
FIELD 
     The invention relates to an electromechanical lock, and to a method in an electromechanical lock. 
     BACKGROUND 
     Electromechanical locks are replacing traditional locks. Further refinement is needed for making the electromechanical lock to consume as little electric energy as possible, and/or improving the break-in security of the electromechanical lock, and/or simplifying the mechanical structure of the electromechanical lock. 
     EP 3118977 describes an electromechanical lock utilizing magnetic field forces. 
     EP 2302149 discloses a lock cylinder utilizing a first drive magnet and a second compensation magnet against external magnetic fields. 
     DE 102008018297 discloses a lock cylinder utilizing opposite poles of an actuator magnet and two stationary permanent magnets. 
     EP 1443162 discloses a lock cylinder utilizing by an axial motion two permanent magnets. 
     EP 2248971 and FR 2945065 disclose a lock utilizing an electromagnet to move an arm with one permanent magnet at each end. 
     BRIEF DESCRIPTION 
     The present invention seeks to provide an improved electromechanical lock, and an improved method in an electromechanical lock. 
     According to an aspect of the present invention, there is provided an electromechanical lock as specified in claim  1 . 
     According to another aspect of the present invention, there is provided a method in an electromechanical lock as specified in claim  11 . 
    
    
     
       LIST OF DRAWINGS 
       Example embodiments of the present invention are described below, by way of example only, with reference to the accompanying drawings, in which 
         FIGS. 1 and 7  illustrate example embodiments of an electromechanical lock; 
         FIGS. 2A, 2B, 3A, 3B, 4A, 4B, 5A, 5B, 5C, 6A and 6B  illustrate example embodiments of an opening sequence; 
         FIGS. 8, 9, 10 and 11  illustrate example embodiments of magnetic fields; and 
         FIG. 12  is a flow chart illustrating example embodiments of a method. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     The following embodiments are only examples. Although the specification may refer to “an” embodiment in several locations, this does not necessarily mean that each such reference is to the same embodiment(s), or that the feature only applies to a single embodiment. Single features of different embodiments may also be combined to provide other embodiments. 
     Furthermore, words “comprising” and “including” should be understood as not limiting the described embodiments to consist of only those features that have been mentioned and such embodiments may contain also features/structures that have not been specifically mentioned. 
     The Applicant, iLOQ Oy, has invented many improvements for the electromechanical locks, such as those disclosed in various EP and US patent applications/patents, incorporated herein as references in all jurisdictions where applicable. A complete discussion of all those details is not repeated here, but the reader is advised to consult those applications. 
     Let us now turn to  FIGS. 1 and 7 , which illustrate example embodiments of an electromechanical lock  100 , but with only such parts shown that are relevant to the present example embodiments. 
     The electromechanical lock  100  comprises an electronic circuit  112  configured to read data  162  from an external source  130  and match the data  162  against a predetermined criterion. In an example embodiment, besides reading, the electronic circuit  112  may also write data to the external source  130 . 
     The electromechanical lock  100  also comprises an actuator  103  comprising a permanent magnet arrangement  109  movable from a locked position to an open position by electric power. 
     The electromechanical lock  100  also comprises an access control mechanism  104  configured to be rotatable  152  by a user. 
     In the locked position, the permanent magnet arrangement  109  is configured and positioned to direct a near magnetic field  153  to block the access control mechanism  104  to rotate, and simultaneously the permanent magnet arrangement  109  is configured and positioned to attenuate the near magnetic field  153  towards a far magnetic break-in field  172  originating from outside  170  of the electromechanical lock  100 . 
     In the open position, the permanent magnet arrangement  109  is configured and positioned to direct a reversed near magnetic field  153  to release the access control mechanism  104  to rotate, and simultaneously the permanent magnet arrangement  109  is configured and positioned to attenuate the reversed near magnetic field  153  towards the far magnetic break-in field  172 . 
     In an example embodiment, the far magnetic break-in field  172  is generated by a powerful external magnet  170 , such as a permanent magnet or an electromagnet, used by an unauthorized user such as a burglar, for example. 
     In an example embodiment shown in  FIG. 1 , the electronic circuit  112  electrically controls  164  the access control mechanism  104 . 
     In an example embodiment, an electric power supply  114  powers  160  the actuator  103  and the electronic circuit  112 . 
     In an example embodiment, the electric energy  160  is generated in a self-powered fashion within the electromechanical lock  100  so that the electric power supply  114  comprises a generator  116 . 
     In an example embodiment, rotating  150  a knob  106  may operate  158  the generator  116 . 
     In an example embodiment, pushing down  150  a door handle  110  may operate  158  the generator  116 . 
     In an example embodiment, rotating  150  a key  134  in a keyway  108 , or pushing the key  134  into the keyway  108 , may operate  158  the generator  116 . 
     In an example embodiment, rotating  150  the knob  106 , and/or pushing down  150  the door handle  110 , and/or rotating  150  the key  134  in the keyway  108  may mechanically affect  152 , such as cause rotation of, the access control mechanism  104  (via the actuator  103 ). 
     In an example embodiment, the electric power supply  114  comprises a battery  118 . The battery  118  may be a single use or rechargeable accumulator, possibly based on at least one electrochemical cell. 
     In an example embodiment, the electric power supply  114  comprises mains electricity  120 , i.e., the electromechanical lock  100  may be coupled to the general-purpose alternating-current electric power supply, either directly or through a voltage transformer. 
     In an example embodiment, the electric power supply  114  comprises an energy harvesting device  122 , such as a solar cell that converts the energy of light directly into electricity by the photovoltaic effect. 
     In an example embodiment, the electric energy  160  required by the actuator  103  and the electronic circuit  112  is sporadically imported from some external source  130 . 
     In an example embodiment, the external source  130  comprises a remote control system  132  coupled in a wired or wireless fashion with the electronic circuit  112  and the actuator  103 . 
     In an example embodiment, the external source  130  comprises NFC (Near Field Communication) technology  136  containing also the data  162 , i.e., a smartphone or some other user terminal holds the data  162 . NFC is a set of standards for smartphones and similar devices to establish radio communication with each other by touching them together or bringing them into close proximity. In an example embodiment, the NFC technology  136  may be utilized to provide  160  the electric energy for the actuator  103  and the electronic circuit  112 . In an example embodiment, the smartphone or other portable electronic device  136  creates an electromagnetic field around it and an NFC tag embedded in electromechanical lock  100  is charged by that field. Alternatively, an antenna with an energy harvesting circuit embedded in the electromechanical lock  100  is charged by that field, and the charge powers the electronic circuit  112 , which emulates NFC traffic towards the portable electronic device  136 . 
     In an example embodiment, the external source  130  comprises the key  134  containing the data  120 , stored and transferred by suitable techniques (for example: encryption, RFID, iButton® etc.). 
     As shown in  FIG. 1 , in an example embodiment, the electromechanical lock  100  may be placed in a lock body  102 , and the access control mechanism  104  may control  154  a latch (or a lock bolt)  126  moving in  156  and out (of a door fitted with the electromechanical lock  100 , for example). 
     In an example embodiment, the lock body  102  is implemented as a lock cylinder, which may be configured to interact with a latch mechanism  124  operating the latch  126 . 
     In an example embodiment, the actuator  103 , the access control mechanism  104  and the electronic circuit  112  may be placed inside the lock cylinder  102 . 
     Although not illustrated in  FIG. 1 , the generator  116  may be placed inside the lock cylinder  102  as well. 
     In an example embodiment illustrated in  FIG. 7 , the actuator  103  also comprises a moving shaft  502  coupled with the permanent magnet arrangement  109 . The moving shaft  502  is configured to move the permanent magnet arrangement  109  from the locked position to the open position by the electric power. As shown in  FIG. 7 , the permanent magnet arrangement  109  may be coupled with a drive head  504  coupled with the moving shaft  502 . In the shown example embodiments, the moving shaft  502  is a rotating shaft. 
     In an example embodiment illustrated also in  FIG. 7 , the actuator  103  comprises a transducer  500  that accepts electric energy and produces the kinetic motion for the moving shaft  502 . In an example embodiment, the transducer  500  is an electric motor, which is an electrical machine that converts electrical energy into mechanical energy. In an example embodiment, the transducer  500  is a stepper motor, which may be capable of producing precise rotations. In an example embodiment, the transducer  500  is a solenoid, such as an electromechanical solenoid converting electrical energy into the kinetic motion. 
     Now that the general structure of the electromechanical lock  100  has been described, let us next study its operation, especially related to the actuator  103  in more detail with reference  FIGS. 2A, 2B, 4A and 4B . 
       FIGS. 2A and 2B  show the permanent magnet arrangement  109  in a locked position  260 , whereas  FIGS. 4A and 4B  show the permanent magnet arrangement  109  in an open position  400 . 
     As was mentioned earlier, the permanent magnet arrangement  109  interacts with the access control mechanism  104  through magnetic forces  153 . 
     In an example embodiment, the permanent magnet arrangement  109  comprises a first permanent magnet  200  and a second permanent magnet  210  configured and positioned side by side so that opposite poles  204 / 214 ,  202 / 212  of the first permanent magnet  200  and the second permanent magnet  210  are side by side. 
     In an example embodiment of  FIGS. 2A and 2B , in the locked position  260 , the first permanent magnet  200  is configured and positioned nearer to the access control mechanism  104  than the second permanent magnet  210  so that the near magnetic field  280 A,  280 B is directed to block the access control mechanism  104  to rotate. Simultaneously, the second permanent magnet  210  is configured and positioned to diminish the near magnetic field  280 A,  280 B towards the far magnetic break-in field  172 . 
     In an example embodiment of  FIGS. 4A and 4B , in the open position  400 , the second permanent magnet  210  is configured and positioned nearer to the access control mechanism  104  than the first permanent magnet  200  so that the reversed near magnetic field  410 A,  410 B is directed to release the access control mechanism  104  to rotate. Simultaneously, the first permanent magnet  200  is configured and positioned to diminish the reversed near magnetic field towards the far magnetic break-in field  172 . 
     In an example embodiment, the electromechanical lock  100  comprises the first permanent magnet  200  and the second permanent magnet  210  as separate permanent magnets fixed to each other. With this example embodiment, the permanent magnet arrangement  109  may be implemented by selecting suitable stock permanent magnets with appropriate magnetic fields and forces. A permanent magnet is an object made from a material that is magnetized and creates its own persistent magnetic field. 
     In an example embodiment, the electromechanical lock  100  comprises a polymagnet incorporating correlated patterns of magnets programmed to simultaneously attract and repel as the first permanent magnet  200  and the second permanent magnet  210 . With this example embodiment, the permanent magnetic arrangement  109  may be implemented even with a single polymagnet. By using a polymagnet, stronger holding force and shear resistance may be achieved. Additionally, correlated magnets may be programmed to interact only with other magnetic structures that have been coded to respond. This may further improve shielding against the far magnetic break-in field  172 . 
     In an example embodiment, the permanent magnet arrangement  109  comprises one or more additional permanent magnets. These additional permanent magnets are positioned and configured, in the locked position  260 , to amplify the near magnetic field  280 A,  280 B to block the access control mechanism  104  to rotate, and/or to further attenuate the near magnetic field  280 A,  280 B towards the far magnetic break-in field  172 . The additional permanent magnets are positioned and configured, in the open position  400 , to amplify the reversed near magnetic field  410 A,  410 B to release the access control mechanism  109  to rotate, and/or to further attenuate the reversed near magnetic field  410 A,  410 B towards the far magnetic break-in field  172 . These additional permanent magnets may be implemented as described earlier: as separate (stock) permanent magnets or as one or more polymagnets incorporating correlated patterns of additional magnets. 
     In an example embodiment, the access control mechanism  104  comprises one or more movable magnetic pins  220 ,  240  configured and positioned to block the access control mechanism  104  to rotate when affected by the near magnetic field  280 A,  280 B, or to release the access control mechanism  104  to rotate when affected by the reversed near magnetic field  410 A,  410 B. 
     In an example embodiment, the magnetic pins  220 ,  240  may be permanent magnets coated by suitable material withstanding wear and force, or permanent magnets attached to pin-like structures. 
     In an example embodiment, the movable magnetic pin  220 ,  240  comprises a main permanent magnet  224 ,  244  configured and positioned to interact with the permanent magnet arrangement  109 , and an auxiliary permanent magnet  222 ,  242  configured and positioned to attenuate a magnetic field of the main permanent magnet  224 ,  244  towards the far magnetic break-in field  172 . 
     In an example embodiment illustrated in  FIGS. 2A and 4A , the permanent magnet arrangement  109  comprises a first axis  270  between the poles, and the magnetic pin  220 ,  240  comprises a second axis  272 ,  274  between the poles, and the first axis  270  is transversely against the second axis  272 ,  274  both in the locked position  260  and in the open position  400 . As shown in  FIGS. 2A, 2B, 4A and 4B , the permanent magnet arrangement  109  is facing sideways (=along the first axis  270 ) the other end (in our example embodiment, the north pole  232  of the first magnetic pin  220 , and the north pole  252  of the second magnetic pin  252 ) of the magnetic pin  220 ,  240 . Note also that the magnetic pins  220 ,  240  may be positioned so that their ends  232 ,  252  are facing the opposite ends (along the first axis  270 ) of the permanent magnet arrangement  109 . 
     Even though Figures illustrate two magnetic pins  220 ,  240 , also such an example embodiment is feasible, wherein only one magnetic pin  220 / 240  is used. 
     Also, in an alternative example embodiment, the permanent magnet arrangement  109  comprises the main permanent magnet and the auxiliary permanent magnet (as described earlier for the magnetic pin  220 ,  240 ), and the magnetic pin  220 ,  240  comprises the first permanent magnet and the second permanent magnet (as described earlier for the permanent magnet arrangement  109 ). In a way, the implementation techniques are reversed from those shown in the Figures. 
     The positions of the permanent magnets  200 ,  210  and the magnetic pins  220 ,  240  and their effect on magnetic fields and the reversed magnetic fields are illustrated in Figures with pole naming conventions, the North pole N and the South pole S: the opposite poles (S-N) attract each other, whereas similar poles (N-N or S-S) repel each other. Consequently, the permanent magnet arrangement  109  comprises the first permanent magnet  200  with the opposite poles  202 ,  204 , and the second permanent magnet  210  with the opposite poles  212 ,  214 . The magnetic pins  220 ,  240  comprise the main permanent magnets  224 ,  244  with their opposite poles  230 ,  232 ,  250 ,  252 , and the auxiliary permanent magnets  222 ,  242  with their opposite poles  226 ,  228 ,  246 ,  248 . 
     In an example embodiment, in the locked position  260 , the permanent magnet arrangement  109  is configured and positioned to direct the near magnetic field  280 A,  280 B to block the access control mechanism  104  to rotate  152  with at least one of the following: the near magnetic field  280 A obstructs the rotation  152  of the access control mechanism  104 , the near magnetic field  280 B decouples the rotation  152  from the access control mechanism  104 . Respectively, in the open position  400 , the permanent magnet arrangement  109  is configured and positioned to direct the reversed near magnetic field  410 A,  410 B to release the access control mechanism  104  to rotate  152  with at least one of the following: the reversed near magnetic field  410 A permits the rotation  152  of the access control mechanism  104 , the reversed near magnetic field  410 B couples the rotation  152  with the access control mechanism  104 . 
     Let us now explain the opening sequence of the electromechanical lock  100  in more detail. 
       FIGS. 2A and 2B  show the permanent magnet arrangement  109  in the locked position  260 ,  FIGS. 3A and 3B  show the permanent magnet arrangement  109  in a transition phase from the locked position  260  to the open position  400 , and  FIGS. 4A and 4B  show the permanent magnet arrangement  109  in the open position  400 . 
     In  FIGS. 2A and 2B , the near magnetic field  280 A pushes the magnetic pin  220  thereby obstructing the rotation  152  of the access control mechanism  104 . This is also illustrated in  FIG. 6A , wherein the magnetic pin  220  is pushed into a notch  600  in the lock body  102 . At the same time, the near magnetic field  280 B pulls the magnetic pin  240  thereby decoupling the rotation  152  from the access control mechanism  104 . This is also illustrated in  FIG. 6A , wherein the magnetic pin  240  is kept from entering a notch  604  in a structure  602 .  FIG. 7  illustrates the structure  602  in more detail: it has a plurality of notches  604  and a projection  704 . The structure  602  operates as a rotating axle, transmitting the mechanical rotation  152  received from the user of the electromechanical lock  100  to the latch control mechanism  124 , thereby retracting  156  the latch  126 . 
     In other words, in the example embodiment illustrated in  FIG. 7 , a first axle  700  is configured to receive rotation by a user and the second axle  602  is permanently coupled with the latch mechanism  124 . In our example embodiment, the rotation  152  by the user is transmitted, in the unlocked position  260  of the actuator  103  through the turning of the first axle  700  in unison with the second axle  602  to the latch mechanism  124  withdrawing  156  the latch  126 . However, a “reversed” example embodiment is also feasible: the first axle  700  may be permanently coupled with the latch mechanism  124  and the second axle  602  may be configured to receive the rotation by the user. If we apply this alternate example embodiment to the  FIG. 1 , this means that the knob  106  (or the key  134  in the keyway  108 , or the handle  110 ) rotates freely in the locked position  260  of the actuator  103 , whereas the backend  602  is blocked to rotate, and, in the open position  400  of the actuator  103 , the backend  602  is released to rotate and the first axle  700  and the second axle  602  are coupled together. 
     In an example embodiment illustrated in  FIG. 7 , the magnetic pins  220 ,  240  may be fitted into hollows  702 . The magnetic pins  220 ,  240  may be configured to move within the hollows  702  by the forces between them and the permanent magnet arrangement  109 . 
     In  FIGS. 3A and 3B , the transition  300  of the permanent magnet arrangement  109  from the locked position  260  to the open position  400  has started. As can be seen, the magnetic pin  240  has started to move. 
     In  FIGS. 4A and 4B , the permanent magnet arrangement  109  has arrived to the open position  400 . The reversed near magnetic field  410 A pulls magnetic pin  220  thereby releasing the rotation  152  of the access control mechanism  104 . This is also illustrated in  FIG. 6B , wherein the magnetic pin  220  is pulled from the notch  600  in the lock body  102 . At the same time, the reversed near magnetic field  410 B pushes the magnetic pin  240  coupling the rotation  152  with the access control mechanism  104 . This is also illustrated in  FIG. 6B , wherein the magnetic pin  240  enters the notch  604  in the structure  602 , whereby the structure  602  transmits the mechanical rotation  152  received from the user of the electromechanical lock  100  to the latch control mechanism  124 , thereby retracting  156  the latch  126 . After this, the door (or another object to which the electromechanical lock  100  is attached to) may be opened. 
       FIGS. 5A, 5B and 5C  illustrate the opening sequence as well: the electric motor  500  turns  300  the rotating shaft  502  clockwise, whereby the drive head  504  rotates the permanent magnet arrangement  109  in relation to the magnetic pins  220 ,  240 . 
       FIGS. 8, 9, 10 and 11  illustrate example embodiments of magnetic fields. 
       FIG. 8  illustrates a prior art arrangement, wherein a single permanent magnet  800  with two poles  802 ,  804  is used, whereas  FIG. 9  illustrates an example embodiment with the first permanent magnet  200  and the second permanent magnet  210  placed side by side as the permanent magnet arrangement  109 . 
     If we compare the solutions of  FIGS. 8 and 9 , we note that with the permanent magnet arrangement  109  both the range and the magnitude of the near magnetic field (and the reversed near magnetic field)  900  is smaller than the magnetic field  810  of the single permanent magnet  800 . In this way, the permanent magnet arrangement  109  is configured and positioned to attenuate the near magnetic field (or the reversed near magnetic field)  900  towards the far magnetic break-in field  172 . 
       FIG. 10  illustrates the example embodiment with the magnetic pin  220  with the main permanent magnet  224  with the two poles  230 ,  232  and the auxiliary permanent magnet  222  with the two poles  226 ,  228 . As shown, the main magnetic field is directed towards the south pole  232  of the main permanent magnet  224 , which enables good interaction with the permanent magnet arrangement  109  and provides diminishing of the magnetic fields towards the far magnetic break-in field  172 . 
       FIG. 11  combines the example embodiments of  FIGS. 9 and 10 , showing the interaction between the permanent magnetic arrangement  109  and the magnetic pin  220  while the north pole  212  is pulling the magnetic pin  220  from the south pole  232  of the main permanent magnet  224 . 
     Next, let us study  FIG. 12  illustrating a method performed in the electromechanical lock  100 . The operations are not strictly in chronological order, and some of the operations may be performed simultaneously or in an order differing from the given ones. Other functions may also be executed between the operations or within the operations and other data exchanged between the operations. Some of the operations or part of the operations may also be left out or replaced by a corresponding operation or part of the operation. It should be noted that no special order of operations is required, except where necessary due to the logical requirements for the processing order. 
     The method starts in  1200 . 
     In  1202 , an actuator is moved from a locked position  260  to an open position  400  by electric power. 
     In the locked position  260 , a permanent magnet arrangement (such as  109 ) directs a near magnetic field to block an access control mechanism (such as  103 ) to rotate in  1204 , and simultaneously the permanent magnet arrangement attenuates the near magnetic field towards a far magnetic break-in field (such as  172 ) originating from outside of the electromechanical lock in  1206 . 
     In the open position  400 , the permanent magnet arrangement directs a reversed near magnetic field to release the access control mechanism to rotate in  1208 , and simultaneously the permanent magnet arrangement attenuates the reversed near magnetic field towards the far magnetic break-in field in  1210 . The rotation obtained from the user of the electromechanical lock may now be used to open the latch in  1212 . 
     The method ends in  1214 . 
     The already described example embodiments of the electromechanical lock  100  may be utilized to enhance the method with various further example embodiments. For example, various structural and/or operational details may supplement the method. 
     It will be obvious to a person skilled in the art that, as technology advances, the inventive concept can be implemented in various ways. The invention and its embodiments are not limited to the example embodiments described above but may vary within the scope of the claims.