SE542573C2 - Charging and communication unit comprising inductive transmission between two cooperating mutually moving parts - Google Patents

Abstract

Charging and communication unit comprising a primary circuit board (1) and a secondary circuit board (2), which circuit boards (1, 2) are arranged in each part of two cooperating parts (90, 91) in a device, which parts (90, 91 ) are mutually movably arranged with each other, where a first part (91) is supplied with power from an external source while a second part (90) is inductively supplied via said first part (91), that said primary circuit board (1) cooperates with a primary coil ( 3) and said secondary circuit board (2) cooperates with a secondary coil (4) for inductive transmission of electrical energy between the circuit boards (1, 2) via said primary (3) and secondary coil (4), said primary (3) and secondary coils (4) are also arranged to inductively transmit data communication between said circuit boards (1, 2).

Description

The present invention relates to a charging and communication unit comprising a primary circuit board and a secondary circuit board, which circuit boards are arranged in each part of two interacting parts in a device, which parts are mutually movably arranged between them, where a first part is powered by an external source while a second part is inductively powered via said first part, that said primary circuit board cooperates with a primary coil and said secondary lqets board cooperates with a secondary coil for inductive transfer of electrical energy between the circuit boards via said primary and secondary coil, and an electrical lock comprising said charging and communication unit. Furthermore, the invention relates to a method for operating and charging such an electric lock.

The application constitutes a divisional application from SE-A-125045 6.

STANDARD OF TECHNOLOGY In today's society, more and more are moving from manually operable applications in various devices, e.g. from manual locks to electric locks. However, there are quite a few disadvantages to installing and using electric locks. In order for the lock part that sits in the door itself to receive power, cables are pulled on the outside of the door, which can easily lead to cable breaks and destruction of the cables. To prevent this, there is the option of drilling a channel through the door for that way to reach with the cables to the lock. This is a time-consuming and costly installation and the risk of cable breakage remains. Another variant is to put rails on the outside of the door to hide the cables, which is also not so pretty.

There are locks, for example in hotels, where this problem with the cables is solved by supplying the lock part that sits in the door with batteries, but then the batteries must be regularly inspected and replaced so that they do not risk running out when a guest is housed in the room.

Another problem that applies to today's electric locks is the lack of coded information transmission, which is a requirement that is coming more and more.

Document WO 00/77330 describes a door-mounted electric lock that is controlled, monitored and programmed electronically by a master station, a so-called online lock.

Power is transmitted wirelessly between one locking part in the door and the other locking part in the door frame and data is transmitted via optical or radio link.

BRIEF DESCRIPTION OF THE INVENTION It is an object of the present invention to eliminate or at least minimize the above problems, which is achieved by a charging and communication unit according to claim 1.

Thanks to the invention, both energy and data can be transmitted inductively, which gives the advantage that cables can be excluded to the part of the charging and communication unit that is placed in, for example, a door. This is advantageous in many ways as running cables in/on the door is cumbersome and expensive. With a lock comprising a charging and communication unit according to the invention, the lock insert can have the same shape as a conventional lock plate, which makes it easy for a locksmith who has ready-made milling tools to mill a hole in a door/door frame adapted for said lock insert for recessed mounting of the lock insert. Through this assembly without cables, you also get rid of the problem of wear/damage to cables that are on the outside of doors.

According to another aspect of the invention, it is also advantageous from an environmental aspect as batteries do not need to be used and less cable is used. Furthermore, impaired charging function is avoided due to that charging pins become worn or oxidized.

According to a further aspect of the invention, the charging and communication unit offers a simple way to detect possible manipulation of the lock and can thereby send an alarm.

According to another aspect of the invention, the advantage is given that through a hand-held unit that provides sufficient drive current to open, for example, a lock in a place not connected to power can be used.

According to yet another aspect of the invention, a capacitor is used in the wireless part, which provides a long service life and stable operation.

According to a further aspect of the invention, the advantage is obtained that no peripheral components need to be used.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will hereinafter be described in more detail with reference to the attached drawings, in which: Fig. 1 shows a block diagram of a primary circuit board according to the invention, Fig. 2 shows a block diagram of a secondary circuit board according to the invention, Fig. 3 shows a primary lock insert according to the invention, Fig. 4 shows a secondary lock insert according to the invention, Fig. 5 shows an electric lock in a door and door frame according to the invention, Fig. 6 shows a block diagram of a primary circuit board according to the invention, Fig. 7 shows various signals schematically, Fig. 8 shows various signals schematically, and Fig. 9 shows a schematic more detailed figure of a pulse width module according to the invention.

DETAILED DESCRIPTION OF THE FIGURES In the shown solution, a preferred embodiment of the invention is described in the following figures. The charging and communication unit according to the invention is intended to cooperate between two different parts. In the example described below, it is described how the charging and communication unit is connected to an electric lock in a vertically placed door and associated door frame, but it should be understood that the invention works just as well on doors/gates of a different kind than the one described here. It should also be understood that the charging and communication unit can be used in applications other than electric locks, such as handheld devices e.g. barcode scanners.

Figure 1 shows a block diagram of a primary circuit board 1 according to the invention, the primary circuit board 1 comprises a first drive stage 11, a first communication module 12, a pulse width module 13, a primary coil 3, a first pulse reception module 14 and a first processor 10. Said primary circuit board 1 is further connected to a fixed power supply 5 and arranged in a door frame.

Figure 2 shows a block diagram of a secondary circuit board 2 which includes a secondary coil 4, a second driver stage 21, a second communication module 22, a second pulse receiving module 23 and a second processor 20. Said secondary circuit board 2 is further connected to a cell 6 such as a battery or a capacitor and the secondary circuit board 2 is arranged in a door.

Below follows a more detailed description of what some of the different parts in the two-circuit boards 1, 2 include, but it should be understood that other variants are also possible without impairing the function of the electric lock.

Both the first and second processors 10, 20 preferably have built-in hardware functions such as Timers, UART, etc. to save space on the primary and secondary circuit boards 1, 2 and to reduce costs.

The first and second communication modules 12, 22 comprise a standard circuit system for modulating and demodulating bit streams, for example RS232.

The communication module 12, 22 can be integrated in the processor 10, 20.

The first and second driver stages 11, 21 comprise in their basic form N-channel MosFET, mosfet driver IC, capacitors and resistors to drive the current at the generating carrier frequency through the primary and secondary coils 3, 4 to create a magnetic field.

The first and second pulse receiving modules 14, 23 comprise full-wave Schottky rectifiers, capacitors, resistors, optocouplers/transistors to handle the energy that said primary and secondary coils 3, 4 take up.

The primary 1 and secondary 2 circuit boards also include a diode bridge (not shown) which diode bridge converts alternating current to direct current. Before the diode bridge, the transmitted pulses for communication are picked out in the first or alternatively in the second communication module 12, 22. Otherwise, the communication pulses are destroyed in the rectification direction.

With reference to figures 3, 4 and 5, it will now be described how the locking device according to the invention can be arranged in a door. The embodiment describes a preferred embodiment and other ways of arranging the devices according to the invention are of course conceivable within the framework of the inventive idea.

Figures 3 and 4 show two cooperating locking inserts 7, 8 which are arranged in a door and a door handle respectively. The locking inserts are identical in appearance and arranged mirror-image to each other. The description below thus refers to both lock inserts 7, 8, although reference is sometimes made to the lock insert which is door-mounted or barrel-mounted. In cases where a specific locking insert is intended, the term primary locking insert 7 and secondary locking insert 8 are used, while reference to a locking insert thus refers to any of the two.

The lock insert 7, 8 preferably has the same shape as a conventional lock plate 9 (see Fig.5), i.e., elongated and with a flat front, which makes it easy for a locksmith who has ready-made milling tools to mill a hole in a door/door frame adapted for said locking insert 7, 8 for recessed mounting of the locking insert.

Figure 4 shows the front of a locking insert in a perspective view. The locking insert 7, 8 comprises a mounting plate 73, 83 with mounting holes 72, 82 for e.g. screws at each end. The front/outer side of the mounting plate 73, 83 runs flush with the door frame when the locking insert 7, 8 is arranged in the door 90/door frame 91.

The back side of the locking insert 7, 8 is best seen in figure 3. On the back/inner side 71, 81 of the mounting plate there is a preferably elongated projecting section 74, 84 around which the coil 3, 4 is wound. For the application described below, the coil 3, 4 is preferably constructed of copper wire with a diameter of 0.6 mm which is wound 16 turns around the elevation 74, 84. The coil has a length of 112 mm, a height of 16 mm and a width of 5 mm . The primary coil 3 in the primary locking insert 7 and the secondary coil 4 in the secondary locking insert 8 are wound exactly the same and tuned so that they are in resonance with each other, i.e. size, number of turns, thickness of wire and resistance and capacitance in the wire are equal. The locking insert 7, 8 further comprises the primary and secondary circuit boards 1, 2 to which the primary and secondary coils 3, 4 are connected. The circuit board 1, 2 is preferably arranged on the planar part 75, 85 of the projecting section. To protect the coil 3, 4 and the circuit board 1, 2, the locking insert 7, 8 preferably includes a casing which can be arranged around the elevation 74, 84 and its parts (not shown) .

Figure 5 schematically shows an electric lock according to the invention mounted in door 90 and door handle 91. During installation, holes are milled for the lock inserts 7, 8 in door 90 and door frame 91, respectively, and the secondary lock insert 8 is connected via, for example, a small channel to the lock in the door. The primary locking insert 7 is connected to a fixed power supply 5 arranged in connection with the door frame or its vicinity. The two locking inserts 7, 8 are mainly arranged opposite each other and mirrored with preferably an air gap between them of a maximum of 30 mm when the door is closed. The primary locking insert 7 preferably includes a magnet that senses when the door is closed (not shown).

The function of the electric lock must now be described with reference to the two circuit diagrams shown in figures 1 and 2. In the figures, the arrows represent electrical signals (so-called pulse trains) that are sent between the outputs and inputs of the various components, and the arrows indicate the direction in which the signal travels. Furthermore, a solid arrow symbolizes command/energy transfer initiated by the primary processor 10 while a dashed arrow symbolizes command/energy transfer initiated by the secondary processor 20. Dashed arrows can also be said to symbolize standby mode.

The primary circuit board 1 (see figure 1) in the door frame 91 has, in addition to transmitting/receiving data, the task of generating a pulse train C which is sent to the primary coil 3 to create a magnetic field which inductively transfers energy and data to the secondary coil 4 in the door 90. The secondary circuit board 2 is tasked with converting the inductively generated signal from the secondary coil 4 into data and energy and processing and responding to the data being transmitted.

The first processor 10 generates a pulse width modulated signal B intended for energy transfer to a first input b on a first drive stage 11 and intended as a carrier wave for data communication. The pulse width modulated signal B is a DC voltage and preferably has a fixed frequency with a voltage amplitude matched to the characteristic of the primary coil 3 (in this case 12 V DC). The processor 10 also sends a pulse train A that is intended for data communication to a first input a of a pulse width module 13, possibly via an external communication module 12 for modifying the pulse train A from parallel to serial communication if such a unit is not integrated in the processor 10. Parallel to the pulse train A is sent also a bypass signal A" from the processor to a second input a" of the pulse width module 13 which is superior to the pulse train A so that an outgoing signal A" from the pulse width module 13 to a second input" of the first drive stage 11 is adapted to achieve different operating cases of the locking device ( see figure 6 and description of different operating cases further on). The output signal A" from the pulse width module 13 is used to control (on/off) the output of the first driver stage 11 to the primary coil 3 at a frequency determined by the data communication and therefore varies continuously. From the output of the first driver stage a magnetic field inducing signal/pulse train C is sent to the primary coil 3 which is a result of the signal A" from the pulse width module 13 influencing the pulse width modulated signal B from the processor 10. In the primary coil 3, a magnetic field is generated whose strength is determined by the current sent through the coil from the fixed current connection 5 and the frequency of the pulse train C. The signal transmitted from the primary coil is a simulated AC voltage.

The induced signal D is taken out at each end of the secondary coil 4 and sent to each input of a second pulse receiving module 23 on the secondary circuit board 2. While the pulse receiving module 23 is rectified and the voltage level of the signal D is adjusted. From the pulse receiving module 23 a pulse train E is sent which is intended pre-data communication to the second processor 20, possibly via an external secondary communication module 22 for modifying the pulse train from serial to parallel communication if such a unit is not integrated in the processor 20. From the second pulse reception module 23, inductive energy is also extracted for charging an electric cell 6, which can be a battery but preferably a capacitor for driving the components in the second circuit board 2.

The secondary circuit board 2 has connected its receiving second communication module 22 to its secondary coil 4 connections in order to receive the communication generated inductively by the primary circuit board 1 at the same time as the inductive energy in turn charges the cell 6 which is connected to the secondary circuit board 2. In order for the secondary circuit board 2 to be able to respond to the data received from the primary circuit board 1, a second drive stage 21 and a second processor 20 are connected just like the primary circuit board 1 and in order for the primary circuit board 1 to be able to receive data, it is connected like the the secondary circuit board 2 with the exception of the cell 6. In this method, one can thus charge and communicate between the primary 1 and the secondary 2 circuit board inductively via the respective coils 3, 4. The second processor 20 generates two signals which are connected to a second drive stage 21. Partly a pulse width modulated signal F intended as a carrier wave for the data communication and partly a pulse train G, via the second communication module 22, intended for the data communication which is used to control the output of the second drive stage 21 for modulating the response signal H which is transmitted via the secondary coil 4 to the primary circuit board 1. Because it primary circuit board 1 must be able to receive data, there is a first pulse receiving pulse width module 14 which, in the same way as with the secondary circuit board 2, counters the signal H from both ends of the primary coil 3. The first pulse receiving pulse width module 14 rectifies the signal H and forwards it to the first processor 10 via the first communication module 12. The signal H from the secondary circuit board 2 is only intended to transmit data communication and therefore the energy in this signal can be kept at a low level. This means that a very small capacity of the electrical cell 6 in the secondary circuit board is sufficient. In addition, the cell 6 must have the capacity to operate the lock during a door opening. Furthermore, this means that control of possible intrusions is facilitated because a small impact on the door/lock causes the response signal from the secondary circuit board 2 to be disturbed, which becomes a trigger signal of intrusion.

In this method, communication can thus be sent inductively via the respective coils 3, 4 between the primary 1 and the secondary 2 circuit board at the same time as the secondary circuit board 2 is charged with electrical energy.

With reference to figures 6, 7 and 8, some different operating cases will now be described.

As mentioned above, the first processor 10 generates a pulse width modulated signal B intended for energy transfer to a first input b of a first drive stage 11. In general, it can be said about energy transfer by means of pulse width modulation (PWM) that the pulse train B which is generated is a square wave consisting of a part where the pulse is high, ON, and a part where the pulse is low, OFF. The effect of the pulse-width modulated signal B can be increased or decreased by varying the distribution between PÄ and OFF, i.e. the duty cycle, and the more you increase the proportion of PÄ, the higher the power of the pulse train. Omnn exenipei 10% ON een 90% Off is obtained a but effect while em 100% ON is obtained fn11effekt.

Energy transfer combined with data communication Through his development work, the applicant has developed a lock where it has become possible to combine inductive transfer of energy with data communication, which as far as the applicant is aware has not been done before. In order for the transmission of energy and data to work, a fixed frequency is used and with a voltage amplitude that is tuned to the primary 3 and secondary 4 coil so that the two coils 3, 4 are in resonance with each other. This results in a high efficiency/transfer function, which cannot be achieved if different frequencies are used. At 50% ON and 50% OFF, the most charge is obtained versus the best speed and best range for communication/data transfer. At 50% ON and 50% OFF, a pulse train B is obtained to the first input b of the first drive stage 11, where each pulse consists of a partial pulse of 50% ON and a partial pulse of 50% OFF. The pulse width modulated signal B is in this case a DC voltage of 230 kHz, 12 V DC. If the characteristics of the coils are changed so that resonance in the coils occurs at a higher frequency, it means that the speed of the data transmission can be increased.

The pulse width modulated signal B is always subordinate to the signal from the first pulse width module 13, i.e. the pulse train A" which means that the pulse width modulated signal B is further modulated by the communicating pulse train A" so that the output signal C from the first drive stage 11 has an appearance consisting of a pulse train with an appearance according to A" but where the PÄ pulses also have a 50/50 characteristic according to signal B.

The pulse train A" is in turn a result of the possible modulation from the bypass signal A' of the data communication signal A. In the event that it is desired to transmit energy and data, the bypass signal A" is naturally set low in a second 130 of two series-connected transistors in the pulse width module 13 whereby the data communication signal A is affected by the first pulse width module 13 via the first 131 of the two-series connected transistors (see figure 6). The output pulse train A" is thus identical to the data communication signal A, i.e. in data transmission A = A" which is shown in figure 7 where the pulse train A is modulated to send data information (the pulse train shown corresponds to a character, e.g. a letter), and where the the outgoing signal C has the same characteristic, but the respective PÄ pulse in the pulse train has a 50/50 characteristic according to the signal B.

Figure 9 shows schematically a more detailed figure of the first pulse width module 13, which includes said first transistor 131 (which is an NPN transistor) and said second transistor 130 (which is a PNP transistor) and 5 resistors Rl, R2, R3, R4 , R5. Resistom's R2 placement depends on the make and type of "Mosfet Driver IC". In the example shown, an MCP14E4 is used, with weak pull-up on only the enable leg, from Microchip. The resistor R2 helps the "Mosfet Driver IC" to go high, because the internal resistor connected to the plus voltage cannot pull the enable pin high by itself, when the second PNP transistor 130 is closed. The values of the resistors Rl, R2, R3, R4, R5 are dimensioned according to the characteristics of the two transistors 131 and 130 and the 'Mosfet Driver IC', and the characteristics themselves differ between make and model number and therefore the resistance values can also vary. To a person skilled in the art, their location is obvious. Most of them are pure pull-up/pull-down and the rest are series resistors (R4, R5) which limit the current to the base of the transistors 130, 131.

As described above, in the event that it is desired to transfer energy and data, the bypass signal A" is set to a low state which then allows current to flow through the second transistor 130 from emitter to collector. The first transistor 131 is controlled by the data communication signal A, so when the data communication signal A is high (PÄ), current also flows through the first transistor 131, from collector to emitter. Since the emitter of the first transistor 131 is connected to common ground / 0 V with the second transistor 130, the second input a" of the first driver stage will be pulled low every time the data communication signal A is high (PÄ) and thus closes the first drive stage's output c. However, every time the trip data communication signal A is low (OFF), the first drive stage's second input a" is pulled high because there is then no connection to common ground/0 V. This results in the first drive stage's 11 other input a" is pulled high by the resistor R2 whereupon the pulse-width modulated signal B which enters the first input of the first drive stage vibrates out at the output c of the first drive stage. In this way the control data communication signal A over the output signal A" from the first pulse width module 13 via the first 131 and the second 130 transistor and the output signal C from the first drive stage 11 is then subordinate to the data communication signal A.

In data communication, the pulse width modulated signal B is thus modulated by the pulse train A" at the speed that the pulse train A" has. The pulse width modulated signal B thus always has a carrier frequency of 50% ON and 50% OFF, but then the signal B is further modulated by the signal A" in that the signal A" controls the output c of the first drive stage 11 to the coil 3. If data is sent, more pulse trains are obtained with 50 /50% and if little data is sent, fewer pulse trains are obtained with 50/50%, which means that the more data that is sent, the more energy can be transferred. The energy transfer is thus to a certain extent proportional to the amount of data that is transferred. In addition, the energy transfer is also proportional to the current data in that the respective characters have different configurations of PÄ pulses and AV pulses respectively. The signal C has a characteristic of 50/50 in the PÄ pulses but due to the characteristic of the two coils, (the inductance of the coil together with a capacitor that sits parallel above the coil, so-called LC coupling or resonant circuit) a signal D is obtained from the secondary coil 4 where the 50/50 characteristic is eliminated so that the signal D essentially resembles the signal A in the operating case energy transfer and data communication, i.e. D f» A (according to figure 7) or resembles the signal A", i.e. D 2 A' in the operating case fast charging.

Quick charge After opening a door that has an electric lock according to the invention, a quick charge of the cell 6 is run and then 100% PÄ is run (in this described example for approx. 5 s), so no data is then sent to the primary coil 3. In order to be able have the possibility to quickly charge the cell 6, the data communication A" is bypassed by the signal A" in the first pulse width module 13. After rapid charging, the cell 6 is fully charged. When you only wish to transfer energy, the bypass signal A" is set naturally high, whereby the low partial pulses of the data communication signal A" disappear " and is replaced by PÄ pulses in the second transistor, ie A" = A". The output pulse train A"" becomes identical to the bypass signal A", i.e. 100% ON, as shown in figure 8. In the case where no data communication takes place, the signal C to the primary coil 3 has an effect corresponding to 50% ON and 50% OFF , see figure 8. This operating mode is preferably only relevant when you wish to quickly charge the cell 6 in the secondary circuit board 2, while data communication preferably takes place continuously at all other times, i.a. for the purpose of maintenance charging the cell 6 but also to monitor the operation of the lock and ensure that intrusion attempts / manipulation does not take place between periods of normal data communication for the purpose of locking/unlocking the lock.

Referring to Figure 9, the second transistor 130 is closed during fast charging when the bypass signal A" is high so no current flows from emitter to collector in the second transistor 130. This results in the second input of the first driver stage a"" being left floating and interpreted internally in the first drive stage 11 as high whereupon the pulse-width modulated signal B which enters the first input of the first drive stage then exits at the output c of the first drive stage. In this mode, therefore, the data communication signal A cannot control the second input a"" of the first drive stage and the outgoing signal C from the first driver stage 11 looks like the pulse width modulated signal B.

The electric lock includes a magnet that detects when the door is closed and as soon as the door is closed, communication is sent continuously, except during fast charging, to detect possible tampering. The data that is transmitted can be anything, e.g. information about what happens in the door, the position of the plunger, is the door closed, etc. The data information that is transmitted between the two coils 3, 4 is encrypted and the self-encoding takes place in the first 10 or the second 20 process via an encryption key that is in the two processors 10, 20. The encryption key itself is therefore not sent, but the data is sent encoded and then decoded in the receiving processor 10, 20. On a lab scale, it has been possible to carry out tests with a magnet in the lock insert without noticing any significant impact of the magnet, but should it turn out that it lowers the effect noticeably, it is realized that the locking insert is made longer so that the distance between the magnet and the coil is increased.

Communication between the primary 1 and secondary 2 circuit board takes place regularly according to the so-called "master slave polling" system. The primary circuit board 1 (master) will send data to the secondary circuit board 2, (slave), and the secondary circuit board 2 will respond 12 only when the primary circuit board 1 requires so. When secondary circuit board 2 should respond is determined depending on the type of message, e.g. primary circuit board 1 sends "needs fast charging" and when secondary circuit board 2 receives this, it is programmed to respond. At the same time, the primary circuit board 1 knows that it should receive a response from the secondary circuit board 2 and shuts down all charging so that collisions do not occur. When primary circuit board 1 has received a response, it returns to, depending on the response, fast charging or sending unimportant data in order to achieve maintenance charging.

The charging and communication unit according to the invention provides the possibility of receiving information in a simple way that someone is trying to manipulate the lock (intrusion). By regularly sending information about the voltage levels in the secondary circuit board 2, the unit can detect voltage changes if, for example, someone puts a piece of sheet metal in the air gap between the primary l and the secondary 2 circuit board in that the piece of sheet metal steals magnetic field. Then the electric lock must run certain pulses with quick charge because the plate steals magnetic field, quick charge must be run to maintain the charge, in this described example 5 V in the cell 6, so that the cell 6 does not discharge, which triggers an alarm signal.

The first pulse receiving module 14 on the primary circuit board 1 is normally in standby mode to avoid collisions and errors and is only engaged when data is received from the secondary coil 4.

When the electric lock is in operation and the secondary circuit board 2 has received a valid door opening signal, the door can be opened. When the door is opened, energy is drawn from the cell 6 and in the example described, the cell 6 can handle a door opening (i.e. the control mechanism that allows the opening and locking of the lock) and then when the door is closed again it is recharged by running a fast charge. When the fast charging is finished, the data also starts to be transferred and at the same time the maintenance charge of the cell 6. When the contact between the door and the door frame is broken (after receiving a valid opening signal), everything switches off to save energy and when, for example, a magnet detects that the door is closed again then a quick charge is run, in this case in about 5s, and then the door can be opened again. The quick charge function is an important part because it is the charged cell 6 that powers the lock. The fast charging function is made possible thanks to the use of a capacitor and thanks to the use of a capacitor a longer life of the cell 6 and a more stable operation are obtained.

The distance between the primary 1 and the secondary 2 circuit board is advantageously a maximum of 30 mm for the best results of the inductive transfer. Should something come in between that 13 disturbs the magnetic field, an alarm goes off, so manipulation of the lock is extremely difficult because as soon as the communication between the two circuit boards 1, 2 is broken, an alarm goes off. Only with the correct opening signal is it possible to open the door, and coded data transmission in the lock is a requirement that is coming more and more.

It should be understood that the voltage range for high or low signal depends on which voltages are worked with internally on the circuit board, which means that the voltage level for high or low can therefore be varied depending on IC circuits, regulators, etc.

ALTERNATIVE EMBODIMENTS The invention is not limited by what is described above, but can be varied within the framework of the subsequent patent claims. It is understood, for example, that the primary 7 and the secondary 8 locking insert can have other shapes than what is described here, for example, the locking inserts can be longer and thus the coils can be wound so that they become longer and thereby transmit more energy.

Furthermore, the person skilled in the art realizes that the various components can have alternative locations than shown in the figures, and the values of the resistors are dimensioned according to the properties of the transistors without, for that reason, detracting from the idea of the invention.

In the described electric lock, an electric pressure lock is preferably used which locks the door when the door slams shut. Should a door with the electric lock according to the invention be left open for a whole day so that the cell 6 is completely discharged, a quick charge is started as soon as the door is closed again, the first time a lock according to the invention is put into use or if the cell 6 has been completely discharged, a quick charge of approx. 13 s is needed before the lock can be used again. This is a big advantage that makes it advantageous to use this lock in deserted or rarely visited places which may also be exposed to moisture and cold, e.g. a mast. If there is then installed a lock according to the invention at the mast, it is a possibility that the part that sits in the door frame is in a handheld device that the technician who needs access to the mast has with him. The handset is then placed against the lock so that resonance between the coil in the lock and the coil in the handset occurs and fast-charges the time needed to bring more than enough energy to the lock's cell to be able to open the lock (in the described example approx. 13 s). Then no batteries or keys are required to get in and manipulating the lock before outsiders is not simple as both encryption and resonance must be achieved.

The person skilled in the art also realizes that in places where it can be difficult to change batteries or where it is not possible to have a cable, it is very advantageous to have a lock according to the invention. 14 Yet another alternative embodiment is to place some form of casing near the handle which houses the coil along the outer edge of the casing so that when the door is closed, the coil is positioned opposite the door frame where the other coil is placed. Other parts of the lock are then placed inside the cover and in this embodiment no damage to the door is needed at all.

It is also very beneficial to connect the electric lock with a passer system, so you are sure that only authorized personnel can unlock.

It is also understood that instead of a magnet some other form of sensor mechanism could be used Lex. optical or mechanical.

The person skilled in the art also realizes that an alternative embodiment can be that the electric lock includes rechargeable batteries, which however does not provide the same advantages as the use of capacitors.

Claims (4)

1. Charging and communication unit comprising a primary circuit board (1) and a secondary circuit board (2), which circuit boards (1, 2) are arranged in each part of two interacting parts (90, 91) in a device, which parts (90, 91 ) are intermovably arranged between themselves, where a first part (91) is powered by an external source while a second part (90) is inductively powered via said first part (91), that said primary circuit board (1) cooperates with a primary coil (3) and said secondary circuit board (2) cooperates with a secondary coil (4) for inductive transfer of electrical energy between the circuit boards (1, 2) via said primary (3) and secondary coil (4), whereby said primary (3) and secondary coil (4) also are arranged to inductively transmit data communication between said circuit boards (1, 2), wherein said inductive transmission uses a fixed frequency and with a voltage amplitude that is tuned to the primary (3) and secondary (4) coil so that the two coils (3, 4) are in resonance with each other and arranged to simultaneously, inductively transfer both bidirectional data communication and energy between said circuit boards (1, 2), whereby the energy transfer is proportional to the amount of data that is over-protected by more energy being transferred the more data that is sent, characterized by said bidirectional data communication having PÄ pulses , which represent zeros in said bidirectional data communication, whereby the PÄ pulses contribute to said energy transfer and AV pulses, which represent zeros in said bidirectional data communication, whereby the AV pulses have no contribution to said energy transfer. Charging and communication unit according to claim 1, characterized in that said primary coil (3) and said secondary coil (4) are wound exactly the same. Charging and communication unit according to claim 1 or 2, characterized in that said data communication is coded. Charging and communication unit according to claim 3, characterized in that said primary circuit board (1) comprises a first processor (10), that said secondary circuit board (2) comprises a second processor (20) and that :iatakoin:nunilczatiorie iriellari both coils (3, 4 ) is encrypted and the encoding itself is arranged to take place in the first (10) and the second (20) processor respectively via an encryption key that is in both processors (10, 20). 10. 11. 16 Charging and communication unit according to claim 3 or 4, characterized in that said circuit board (1, 2) comprises communication modules (12, 22). Charging and communication unit according to claim 5, characterized in that said communication modules (12, 22) are integrated in said processors (10, 20). Charging and communication unit according to claim 5 or 6, characterized in that said primary and secondary circuit board (1, 2) includes a diode bridge arranged to convert alternating current to direct current and that said data communication is arranged to be supplied to one of said communication modules (12, 22) before the mentioned diode bridge. Charging and communication unit according to any previous claim, characterized in that said primary circuit board (1) is connected to a fixed power supply (5). Charging and communication unit according to any previous claim, characterized in that said primary circuit board (1) further comprises a first drive stage (11), as well as a first pulse width module (13) and a first processor (10) for generating a pulse train (C) comprising electrical energy and data to the primary coil (3) and receiving a response signal (H) comprising data from the secondary coil (4). Charging and communication unit according to one of the above claims, characterized in that said secondary circuit board (2) further comprises a second drive stage (21), a second pulse width module (23) and a second processor (20) receiving an induced signal (D) comprising electrical energy and data from the second coil (4) and generation of said response signal (H). Charging and communication unit according to claims 9 and 10, characterized in that the electrical energy in the induced signal (D) drives the components in the secondary circuit board (2) and that a part of the energy is stored in a cell (6), preferably a capacitor, for use when generating the response signal (H) and possible operation of mechanical components in the second part (90). 1 2. 1 3. 1 4. 17 Electric lock characterized in that it comprises a charging and communication unit according to any of claims 1 - 11. Electric lock according to claim 12 characterized in that said primary circuit board (1) and primary coil (3) are arranged in a first locking insert in a door frame (91), and that said secondary circuit board (2) and secondary coil (4) are arranged in a second locking insert in a door (90), where the locking inserts are arranged essentially opposite each other with an air gap between them when the door is closed, and includes a sensor that detects when the door is closed. Electric lock according to claim 12 or 13, characterized in that said lock inserts include mounting plates (73, 83) at the rear/inner side (71, 81) of which an elongated projecting section (74, 84) is arranged around which said coil (3, 4) is wound .