• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    Derivator of radio frequency signals for electronic door openers, which connects a street panel (1) with electronic door openers (2), comprising first coils (l1, l2) that allow the passage of low frequencies from a call made from the board (1) towards a goalkeeper (2), said goalkeeper (2) activating upon receiving the call and increasing his consumption. Also comprising a detector circuit (5) that detects the activation of a gate (2), and short circuit circuits (6) of the first coils (l1, l2), which are activated when the detector (5) detects the activation of the goalkeeper (2). When a call is made, the higher frequency signals that are transmitted between the electronic gate (2) and the entrance panel (1) pass through the short circuits (6) of the first coils (l1, l2), reducing the transmission losses. (Machine-translation by Google Translate, not legally binding)
    公开号:ES2637755A1
    申请号:ES201630462
    申请日:2016-04-13
    公开日:2017-10-16
    发明作者:Gonzalo De La Torre San Martin；Francisco Javier LOPEZ PEREZ
    申请人:Alcad Electronics SL；
    IPC主号:
    专利说明:

    DESCRIPTION

    RADIO FREQUENCY SIGNAL DERIVATIVE FOR ELECTRONIC PORTERS
     5
    OBJECT OF THE INVENTION

    The present invention relates to a new radio frequency signal shunt whose configuration and design are intended to reduce the losses of passage of the radio frequency signals practically to zero in order to increase the capacity of the installation in which the shunt is installed. , allowing to obtain facilities in which the electronic doormen are located at greater distances and / or with a greater number of electronic doormen.
    BACKGROUND OF THE INVENTION
    Currently, electronic door entry systems consist of one or more street signs 15 and a plurality of electronic door phones, connected through the corresponding transmission lines. Electronic gatekeepers consist of monitors (video intercoms) or telephones installed in homes. In the connection between the different transmission lines are included shunts that allow the passage of radio frequency signals. twenty
    The signals that circulate throughout the installation wiring consist of direct voltage (Vcc) and radio frequency (RF) signals.
    The derivators used are constituted by coils equipped with a magnetic core on which two windings are wound, whose impedance increases with the frequency according to the expression Z = 2πfL, with f being the frequency in Hertz (Hz) and L the inductance in Henrios ( H). The initial value of the inductance is of a low value, of the order micro H, so that it only lets the low frequencies pass. In this context, those frequencies that do not exceed the value of 370KHz are considered low frequencies, a result obtained by applying the criterion that the attenuation caused by a 22 micro H coil, typical value of the inductor of a resting shunt, does not exceed 3dB over a characteristic impedance of 120 Ohms.
    As long as no call is made on the entrance panel, the electronic doormen will
    they are at rest (stand-by) so their direct current consumption (Icc) is minimal.
    On the contrary when a call is made on the street sign (a user presses the call button to a floor) a low frequency signal is generated which, together with a continuous voltage is sent through the transmission lines, so that the continuous voltage 5 is blocked by the shunts, while the low frequency signal passes through the shunts and is consequently received by all electronic gatekeepers, only the electronic gatekeeper to which said call signal is associated is activated.
    When the electronic doorphone to which the call is addressed is activated, an increase in the current (Icc) due to the activation of its internal electronics is generated. This increase in current is transmitted to the shunt saturating its magnetic core, which causes a reduction in its inductance, as described.
    This reduction in inductance allows higher frequencies to pass, higher than 370 KHz, which allows the transmission of video and / or audio between the monitor or telephone 15 of the electronic doorphone and the entrance panel and from the entrance panel. Street to the electronic doorman.
    The problem with current systems is that the inductance of the shunts cannot be reduced to zero, so that even if the inductance is reduced, there is always a residual inductance and consequently an impedance, which generates losses of 20 passage of the radio frequency signal that results in a decrease in the capacity of the installation limiting the distance to which the electronic doormen are located and / or limiting the number of electronic doormen to be used.
    DESCRIPTION OF THE INVENTION
    In order to achieve the objectives and solve the aforementioned drawbacks, the invention provides a new shunt configuration, which, as in the state of the art, is intended to connect at least one street sign with a plurality of electronic doormen, by means of the Transmission line connection. To this end, the shunt comprises first coils that are configured to allow low frequencies from a call made from a street sign 30 to an electronic door intercom, so that when the electronic door intercom receives the
    called, activates what causes an increase in the current consumed by said electronic intercom. This increase in current causes the inductance of the first coils to decrease, thereby allowing higher frequencies to pass, corresponding to the transmission of signals between an electronic doorphone and the entrance panel. Depending on the type of electronic doorphone, the radio frequency signals that are transmitted can be 5 video and audio signals, whether it is a monitor (video intercom) or audio signals if it is a telephone.
    The novelty of the invention is that the shunt is characterized in that it comprises a current sensing circuit, which is configured to detect a current greater than a predetermined threshold. This current higher than the threshold occurs in the shunt when an electronic door intercom is activated upon receiving a call, as commented. Therefore, the current threshold to be detected is set according to the current consumed by the electronic door entry system, which is a function of the type of electronic door entry system used.
    In addition, the shunt comprises second coils that are configured to prevent the passage, to said current detector circuit, of any radiofrequency signal, including those of low frequency coming from a call and directing the low call frequencies to the electronic doormen.

    The shunt also comprises short-circuited circuits of the first 20 coils, which are activated when a current greater than the predetermined threshold is detected.

    According to the described configuration, when a call signal is produced, the first coils are short-circuited, so that the higher frequency signals that are transmitted between the electronic doorphone and the street sign no longer pass through the first 25 coils, but pass through the short circuits of the first coils, which reduces transmission losses, allowing longer transmission lines and / or a greater number of electronic gatekeepers.
    In order to supply the different elements that constitute the shunt, it is provided that it comprises the corresponding power supply, which in an embodiment of the invention is connected to the short-circuited circuits by means of capacitors that prevent the passage of the continuous voltage. feed and allow the
    passage of the radio frequency signals through the short-circuit circuits and thus achieve the functionality described above.

    In addition, in an embodiment of the invention, the detection of the current consumed by the electronic doorphone that is activated by the realization of a call is made by converting the current into voltage, for which the second coils are connected to the first coils and electronic gatekeepers by means of voltage conversion resistors of the current coming from the activated electronic doorman and the current detector is constituted by a voltage comparator to which a reference threshold voltage, previously set, is applied to detect the activation of the electronic doorphone that 10 receives a call.

    The invention provides that the voltage converted by the resistors, coming from the current consumed by the activated electronic intercom, is applied to the voltage comparator by means of voltage amplifiers to adapt the voltage levels 15 required by the voltage comparator so that it performs the Correct detection of the activation of an electronic doorphone.

    The voltage amplifiers are connected to the same input of the voltage comparator, so that this connection is made by means of resistors, to isolate the output 20 of the amplifiers and prevent a short circuit. This is because conventionally, as will be explained later, two lines are used in the shunt, so that it does not have polarity, so that the polarity does not have to be respected when installing the shunts, which facilitates said installation, since the current can circulate in two directions and with both lines both situations are foreseen. 25
    In the preferred embodiment of the invention, each of the short-circuited circuits comprises a first transistor, with corresponding bias resistors, whose operating state is controlled by a second transistor that is connected to the output of the current detector, so that when a voltage greater than the established threshold is detected, by the activation of an electronic doorphone, the 30 second transistor is activated, which in turn causes the activation of the first transistors of the short-circuited circuits, making the short-circuiting of the first coils .

    In addition, the output of the voltage comparator is connected to a voltage stabilizer circuit, whereby it is avoided that any possible interference that may occur in the network could cause the first coils to be short-circuited.
    In order for the invention to be valid for all types of electronic doormen, it is envisaged that it comprises means for regulating the reference threshold voltage, which is selected depending on whether the electronic door entry is a monitor or a telephone, since the monitor has a reference threshold voltage greater than that of the telephone.
    In order to achieve the functionalities described above, the first coils are of a low value, of the order of micro henries and instead the second coils are of a high value, of the order of mili henrios. 10
    Next, in order to facilitate a better understanding of this descriptive report and forming an integral part thereof, a series of figures are attached in which the object of the invention has been shown as an illustrative and non-limiting nature.
    BRIEF DESCRIPTION OF THE DRAWINGS
     fifteen
    Figure 1.- Shows a simplified scheme of a conventional installation of electronic doormen of a building.
    Figure 2.- Shows a simplified schematic representation of the concept of the derivative of the invention.
     twenty
    Figure 3.- Shows a diagram of an example of embodiment of the shunt of the invention.

    DESCRIPTION OF AN EXAMPLE OF EMBODIMENT OF THE INVENTION
     25
    Figure 1 shows a simplified scheme of a conventional installation of electronic doormen of a building, comprising at least one street sign (1) that communicates with a plurality of electronic doormen (2) via transmission lines (TL1-TL6 ), the operation of which is explained below in order to facilitate the understanding of the invention. 30
    The entrance panel (1) is installed on a main transmission line (3), which is
    connects to the shunts (4) via primary transmission lines (TL1-TL3). For example, TL1 could be the primary transmission line that connects the main line (3) with the shunt (4) of the first floor of a floor, TL2 could be the primary transmission line that connects the main line (3) with the shunt (4) of the second floor of a floor, etc. 5
    There are also “secondary” transmission lines (TL4, TL5 and TL6) that connect the shunts (4) with the electronic doormen (2). For example, according to the previous paragraph, TL4 could be the secondary line that connects the shunt (4) of the first floor of a floor with the electronic doormen (2) of said first floor, TL5 could be the secondary line that connects the shunt (4) of the second floor of a floor with the 10 goalkeepers of said second floor, etc.
    In short, TL1 to TL6 are the wiring of the installation with its corresponding inductance and capacitance.
    Continuous voltage (Vcc) and radio frequency (RF) signals are supplied throughout the installation wiring. fifteen
    The shunts (4) comprise two first coils (L1, L2) which are provided with a winding wound on a magnetic core, whose impedance increases with the frequency according to the expression Z = 2πfL; where f is the frequency (in Hertz Hz) and L the Inductance (In Henry H). The inductance value of the windings is low, of the order of micro H. 20
    While no call is made on the street sign (1), the electronic doormen (2) are in a stand-by state in which their direct current consumption (Icc) is minimal.
    When a call is made on the street sign (1), that is, when a user presses the call button to a floor, a low frequency signal is generated, which, as discussed, is a frequency that does not exceed 370 KHz Being a low frequency the signal can pass through the shunt (4) as the first coils (L1, L2) of the order of micro H, and is received by all electronic doormen (2), of which only the doorman will activate electronic (2) to which said call signal is associated. This is due to the fact that each call button on the street sign (1) has an associated identification code for each electronic door entry (2), which each
    said electronic doormen stores, so that when it receives the stored code it is activated.
    When the electronic door intercom (2) is activated, an increase in the current (Icc) is generated due to the activation of its internal electronics. This increase in current is transmitted to the shunt (4) saturating its magnetic core, which causes a reduction in its inductance.
    This reduction of the inductance allows the passage of higher frequencies, that is higher than 370 KHz, for video and / or audio transmission from the monitor or telephone of the electronic doorphone (2) to the street sign (1) .
    The problem with current systems lies in the fact that, even if the inductance is reduced, there is always a residual inductance and consequently an impedance, which generates a loss of passage that results in a decrease in the capacity of the installation, what limits the length that can have or the number of electronic doormen (2) to use.
    Figure 2 shows a schematic representation of the configuration of the shunt (4a) of the invention that solves the aforementioned drawbacks, for which it comprises a current sensing circuit (5) that is configured to detect when the current in the shunt (4a) exceeds a previously established reference threshold, which causes the actuation of a short-circuited circuit (6) that short-circuits the first coils (L1, L2) of the shunt (4a), 20 causing the passage losses of the higher frequencies are negligible (almost nil) thus improving the capacity of the installation.
    Furthermore, the shunt of the invention comprises second coils (L3, L4) of high value, of the order of milli H, by means of which the first coils (L1, L2) are connected to the current detector (5), so that when a call is made on the street sign 25 (1) a low frequency signal is generated which, as in the current shunts, being a low frequency signal crosses the first coils (L1, L2) of the shunt (4a ) without problems and the inductances of the second coils (L3, L4), having a high value, prevent the low frequency radiofrequency signal from leaking into the current detector circuit (5). Therefore, the second coils (L3 and L4) act as a "barrier" 30 to prevent the call signal from passing to the current detector (5).
    It should be noted that the second coils (L3, L4) are also configured to prevent the passage of any frequency to the current detector (5).
    Consequently, the radiofrequency call signal passes to the doormen (2), activating the doorman (2) to whom the call is directed, for example the one represented in Figure 2, which upon receipt is activated, so that it goes from being in a standby state to 5 an active state.
    At the moment when the doorman (2) is activated, the current consumption increases, this increase in current reaches the current detector circuit (5), which compares it to a reference threshold current that has been previously set .
    In the exemplary embodiment, as will be explained in greater detail below, the current is converted to voltage for which the current detector is materialized by a voltage comparator so that when the voltage that reaches the comparator (5) exceeds the value of the reference threshold voltage, due to the increase in current, the comparator circuit (5) activates short-circuited circuits (6), materialized by switches, which are arranged in parallel with the first 15 coils (L1, L2) , so that said first coils (L1 and L2) are shorted.
    In this way, the signal with a higher frequency emitted by the doorman (2) directed to the entrance panel (1), no longer passes through the first coils (L1 and L2), causing the losses to decrease practically to zero and arrives to the street sign through the short circuit. twenty
    A simplified example of a particular embodiment of the shunt (4a) of the invention is detailed in Figure 3.
    The shunt (4a) comprises a power circuit (7) of the different components that constitute it. This power circuit (7) is conventional with the corresponding bridge of diodes, coils, capacitors and resistance, and is not an object of the invention, so its operation is not described in greater detail.
    Conventionally two lines are used in the shunt, to avoid taking polarity into account (in this way the installers are not obliged to connect the cables to the shunt respecting a polarity, thus facilitating the installation) so that the current can circulate both situations are foreseen in both directions. Therefore, the first two coils (L1, L2) are used.
    The second coils (L3, L4) are duplicated to prevent the passage of all the radio frequency signals coming from both the first coils (L1, L2) and the electronic doorphone (2).
    On the main transmission line (3) from the entrance panel (1), the continuous voltage (Vcc) and the radio frequency (RF) signal are supplied to the shunt (4a), as already described.
    Each of the first coils (L1 and L2) of the shunt (4a) is connected to a DC voltage suppressor (23) so that only the radio frequency signal passes through said first coils (L1, L2).
     10
    Each of the short-circuited circuits (6) comprises a first transistor (T1, T2) with the corresponding polarization resistors that establish the working point of said first transistors.
    The first transistors (T1 and T2) are connected to the shunt by means of capacitors (8, 9, 10 and 11) that prevent the continuous voltage (Vcc) from passing through them and, in turn, change the radiofrequency signals that can cross them.
    Therefore, the capacitors (8, 9, 10 and 11) only limit the passage of the continuous voltage (Vcc).
    As already mentioned, the current detector is materialized by means of a voltage comparator (5) so that resistors (12 and 13) are used to convert the current from the doorman (2) into voltage when it has been activated.

    The voltage coming from the resistors (12 and 13) is applied to amplifiers (14) to achieve adequate voltage levels so that the comparator (5) can function correctly. 25
    The output of the amplifiers (14) is connected to the comparator (5) through resistors (15), whose function is to isolate the output of one of the amplifiers from the other to prevent a short.
    The reference threshold voltage is set by means of resistors (16 and 17) and incorporates a selector (18) to indicate to the shunt if the electronic door intercom is a monitor or a telephone. The resistance (16) is variable in order to adjust the reference threshold voltage
    at the level required according to the type of electronic doorman (2) employed. In the exemplary embodiment, the selector (18) is a connector that is kept open for the case where the electronic doorphone is a monitor, or is short-circuited for the case where the electronic doorphone is a telephone, since the threshold Operating voltage of the monitor is greater than that of the phone. 5
    The output of the comparator (5) is connected to a voltage stabilizer (19), whose output is connected to the first transistors (T1, T2) through a second transistor (T3), which is responsible for activating the first transistors (T1 and T2), when the activation of the electronic door entry (2) occurs, which causes the voltage coming from the amplifiers (14) to exceed the reference voltage threshold 10 determined by the resistors (16, 17), short-circuiting the inductances (L1 and L2).
    The second transistor (T3) is connected to the corresponding polarization resistors (20) responsible for setting its working point.
    A led diode (24) is included whose ignition indicates the operation of the shunt (4).
    In accordance with the above description it is readily understood that the full operation of the shunt of the invention would be as follows:
    When a user calls the street sign (1), the voltage (Vcc) and the low frequency signal enter the shunt coming from the main transmission line (3) that connects to the entrance panel (21). street (1) with the shunt (4a).
    The radiofrequency signal crosses (L1 or L2) and goes through the terminal (22) to the doorman 20 (2) through the transmission line that connects the shunt (4a) with the doorman (2).
    The radio frequency signal cannot pass through the second coils (L3, L4,) due to the high value of these inductances.
    If the doorman (2) corresponds to the received call signal, it is activated, increasing its consumption, therefore increasing the current. 25
    This increase in current enters through Terminal (22) and through (12 and 14) or (13 and 14) it becomes voltage. This voltage is directed to the voltage comparator (5) whose threshold ("trigger" level) has been adjusted by means of the resistors (16 and 17).
    If the voltage from (12 and 14) or (13 and 14) exceeds the threshold, the comparator signals the second transistor (T3) to activate the first transistors (T1 and T2) 30
    shorting the first coils (L1 and L2).
    In this way the radiofrequency signal from the doorman (2), which enters through the terminal (22), whose frequency is high, crosses the shunt through one of the first transistors (T1 or T2) of one of the short-circuited circuits ( 6), leaving it by the Terminal (21) in the direction of the street sign (1). The frequencies used in the present example, without thereby losing its generality, are the following: 181KHz for the transmission of the signaling between street panels and electronic gatekeepers, 3.2MHz for the transmission of the signaling and audio between electronic gatekeepers and street signs, and 12.5 MHz for the transmission of video signals between street signs and electronic gatekeepers. 10
    Since said radiofrequency signal does not pass through any of the first coils (L1 or L2), the losses that occur are practically nil.
    权利要求:
    Claims (9)
    [1]

    1.– RADIO FREQUENCY SIGNAL DERIVATIVE FOR ELECTRONIC PORTERS, the shunt being arranged to connect at least one entrance panel (1) with a plurality of electronic doormen (2), through the connection of transmission lines 5 (TL1- TL6), for which the shunt comprises first coils (L1, L2) configured to allow the passage of low frequencies from a call made from a street sign (1) to an electronic doorphone (2), which when receiving said electronic gatekeeper, the low frequency signal, is activated causing an increase in the current consumed by said gatekeeper (2), which decreases the inductance of the first coils (L1, L2), allowing higher frequencies corresponding to the transmission of selected signals between video, audio and combination of both, between a monitor or an electronic door phone (2) and the entrance panel (1), characterized in that it comprises:
     fifteen
    - A current detector circuit (5) configured to detect a current greater than a preset threshold, which occurs when an electronic door intercom (2) is activated when a call is received
    - second coils (L3, L4), configured to prevent the passage of said current detector circuit 20 (5), of the radio frequency signals including those of low frequency from a call to direct the call to the electronic doormen (2 ),
    - short-circuited circuits (6) of the first coils (L1, L2), which are activated when the current detector (5) detects a current greater than the predetermined threshold;
    where when a call signal is produced and the first coils (L1, L2) are short-circuited, the highest frequency signals that are transmitted between the intercom (2) and the 30 entrance panel (1) pass through the short circuits ( 6) of the first coils (L1, L2), reducing transmission losses.
    [2]
    2.- RADIO FREQUENCY SIGNAL DERIVATIVE FOR ELECTRONIC PORTERS, according to claim 1; characterized in that it comprises a source
    supply (7) of the shunt elements, which is connected to the short-circuited circuits (6) by means of capacitors (8, 9, 10 and 11) that prevent the passage of the continuous supply voltage and allow the signals to pass through radio frequency through the short-circuited circuits (6).
     5
    [3]
    3.- RADIO FREQUENCY SIGNAL DERIVATIVE FOR ELECTRONIC PORTERS, according to claim 2; characterized in that the second coils (L3, L4) are connected to the electronic doorphone (2) and to the first coils (L1, L2) by means of resistors (12, 13) of voltage conversion of the current coming from the electronic doorphone (2) activated , voltage that is applied to the current detector (5); said current detector (5) being constituted by a voltage comparator to which a reference threshold voltage, previously set, is applied to detect the activation of the electronic doorphone (2) receiving a call.

    [4]
    4.- RADIO FREQUENCY SIGNAL DERIVATIVE FOR ELECTRONIC PORTERS, according to claim 3, characterized in that the voltage converted by the resistors (12, 13) from the current consumed by the activated electronic doorphone (2) is applied to the comparator of voltage (5), by means of voltage amplifiers (14).
     twenty
    [5]
    5. RADIO FREQUENCY SIGNAL DERIVATIVE FOR ELECTRONIC PORTERS, according to claim 4, characterized in that the output of the voltage amplifiers (14) are connected to the same input of the voltage comparator (5) by means of resistors (15) to isolate the output the amplifiers (14) and prevent a short circuit from occurring. 25

    [6]
    6. RADIO FREQUENCY SIGNAL DERIVATIVE FOR ELECTRONIC PORTERS, according to any one of the preceding claims, characterized in that each of the short-circuited circuits (6) comprises a first transistor (T1, T2), and the output of the current detector (5) is connected to a second transistor 30 (T3) which, when activated, causes the activation of the first transistors (T1, T2) of the short-circuited circuits (6), short-circuiting the first coils (L1, L2).

    [7]
    7.- RADIO FREQUENCY SIGNAL DERIVATIVE FOR ELECTRONIC PORTERS, according to claim 3 or 6, characterized in that at the exit of the
    Voltage comparator (5) comprises a voltage stabilizer circuit to prevent the first coils (L1, L2) from being short-circuited against network interference.

    [8]
    8. - RADIO FREQUENCY SIGNAL DERIVATIVE FOR ELECTRONIC PORTERS, according to claim 1, characterized in that it comprises means for regulating the reference threshold voltage depending on whether the electronic door intercom (2) is a monitor or a telephone.

    [9]
    9. - RADIO FREQUENCY SIGNAL DERIVATIVE FOR ELECTRONIC PORTERS, according to claim 1, characterized in that the first coils 10 (L1, L2) are of a value of the order of micro henry and the second coils (L3, L4) are of a value of the order of mili henrios.
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    引用文献:
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    US5228078A|1991-03-27|1993-07-13|Telko Gmbh|Two-wire intercom with hands-free function|
    US20100061545A1|2008-09-05|2010-03-11|Cottonwood Creek Technologies|Extended Signaling System and Method|
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