Summary of the invention
Main purpose of the present invention is to provide a kind of building conversational system, and it can effectively realize the function of isolating in every family, and it is safe to converse, and job stability is good, uses to have hommization.
In order to reach above-mentioned purpose, solution of the present invention is:
A kind of building conversational system comprises a doorway machine, " 3+n " line cable and n platform indoor set, and wherein n is natural number; Doorway machine comprises that keyboard, MCU and I/O expanded circuit, the tinkle of bells circuit for generating, microphone, loudspeaker, echo are eliminated or automatic half-duplex voicefrequency circuit, the first audio power amplifying circuit, the second audio power amplifying circuit, minute family gating circuit, the control circuit of unblanking, level sensitive circuit and 3+n line interface; Minute family gating circuit is connected to minute family line in " 3+n " line cable by the interface AGND in the 3+n line interface, the first audio power amplifier circuit is connected to " doorway machine is to the tone frequency channel wire of indoor set " of common wire in " 3+n " line cable by the interface A in the 3+n line interface, and echo is eliminated or the half-duplex voicefrequency circuit is connected to common wire in " 3+n " line cable by the interface B in the 3+n line interface automatically " indoor set is to the tone frequency channel wire of doorway machine "; The 3+n line interface of doorway machine is connected with n platform indoor set by " 3+n " line cable, specifically 3 common wires in " 3+n " line cable are connected on 4 line interfaces of n platform indoor set simultaneously, and a n root minute family line is connected respectively in n platform indoor set 4 line interfaces on the remaining interface; Indoor set comprises loudspeaker, microphone, microphone audio amplifying circuit, talking state indicator light, plucks/the on-hook button, unlock key, state control circuit, microphone amplifying circuit switch and 4 line interfaces; State control circuit is connected to respectively " doorway machine is to the tone frequency channel wire of indoor set " of minute family line in " 3+n " line cable and common wire by the interface AGND in 4 line interfaces and interface A, the microphone audio amplifying circuit is connected to " indoor set is to the tone frequency channel wire of doorway machine " of common wire in " 3+n " line cable by the interface B in 4 line interfaces; After MCU and I/O expanded circuit detect the touch-call action of keyboard, minute family line of the control minute called indoor set of family gating circuit gating, and in during the line of gating this minute family, no longer minute family line of corresponding other indoor set of gating.
The family gating circuit comprised a NPN triode, a voltage-stabiliser tube, a base resistance and a current-limiting resistance in above-mentioned minute; One end of base resistance is connected with the gating control end of MCU and I/O expanded circuit, and the other end is connected to the base stage of triode; The collector electrode of triode is connected to interface AGND in the 3+n line interface, grounded emitter via current-limiting resistance; The voltage-stabiliser tube forward is connected between the collector electrode and emitter of triode.
Also be connected with between the interface A in above-mentioned MCU and I/O expanded circuit and the 3+n line interface one under the control of MCU and I/O expanded circuit for " doorway machine is to the tone frequency channel wire of indoor set " provides the dc bias circuit of two kinds of dc offset voltage Vbias1 and Vbias2, and control Vbias2 that indoor set is in talking state and be higher than and control the Vbias1 that indoor set is in ringing condition.
Above-mentioned dc bias circuit comprises a NPN triode Q8, a PNP triode Q7, three resistance R 27, R28, R29 and diode D7, D8; The base stage of triode Q8 is connected with the voltage controling end of MCU and I/O expanded circuit by resistance R 27, grounded emitter, and collector electrode is connected to the base stage of triode Q7 by resistance R 27; The base stage of triode Q7 also is connected to emitter by resistance R 28, and connects bias voltage Vbias2 by this emitter; The diode D8 that the collector electrode of triode Q7 connects by forward is connected to the interface A in the 3+n line interface; And aforementioned interface A also connects bias voltage Vbias1 by the diode D7 of an Opposite direction connection.
Above-mentioned level sensitive circuit comprises a comparator U2A, an electrochemical capacitor C9 and a resistance R 24; The positive input of comparator U2A is connected to interface A in the 3+n line interface by resistance R 24, and negative input connects the first reference voltage; The positive pole of electrochemical capacitor C9 is connected minus earth with the positive input of comparator U2A.
Above-mentioned dc bias circuit also comprises the bias voltage Vbias3 that is connected with interface B in the 3+n line interface by resistance R 26, level sensitive circuit also comprises comparator U2B, resistance R 25 and electrochemical capacitor C11, the positive input of comparator U2B is connected to interface B in the 3+n line interface by resistance R 26, and negative input connects the second reference voltage; The positive pole of electrochemical capacitor C11 is connected minus earth with the positive input of comparator U2B.
After adopting such scheme, the present invention is by increasing the family gating circuit of plusing fifteen in building conversational system, MCU and I/O expanded circuit can be controlled indoor set corresponding to this minute family gating circuit gating according to call request, and in during gating, guarantee no longer all the other indoor sets of gating, thereby remain the communication of " one to one " of doorway machine and indoor set, effectively realized the in every family isolation of conversation.
Embodiment
Below in conjunction with drawings and the specific embodiments feature of the present invention and execution mode are elaborated.
With reference to shown in Figure 1, a kind of building conversational system of the present invention, comprise that (number of corresponding cable is made as the n platform for a hands-free doorway machine 1, one " 3+n " line cable 2 and some hands-free indoor sets 3, n is natural number), wherein hands-free doorway machine 1 is connected with the hands-free indoor set 3 of n platform by " 3+n " line cable 2, specifically 3 common wires in " 3+n " line cable 2 are connected on the hands-free indoor set 3 of n platform simultaneously, and a n root minute family line is connected respectively on the hands-free indoor set 3 of n platform.
Please refer to again shown in Figure 2, hands-free doorway machine 1 in the present embodiment comprises that keyboard 120, MCU (single-chip microcomputer) and I/O expanded circuit 121, the tinkle of bells circuit for generating 110, microphone 111, loudspeaker 112, echo are eliminated or automatic half-duplex voicefrequency circuit 113, audio power amplifier circuit 114 (i.e. the second audio power amplifying circuit) and 115 (i.e. the first audio power amplifying circuits), minute family gating circuit 116, the control circuit 13 of unblanking, level sensitive circuit 14, dc bias circuit 16 and 3+n line interface 15.
With reference to shown in Figure 3, hands-free indoor set 3 in the present embodiment comprises loudspeaker 31, microphone 32, microphone audio amplifying circuit 33, talking state indicator light 34, plucks/on-hook button 35, unlock key 36, state control circuit 37, microphone amplifying circuit switch 38 and 4 line interfaces 39.
Disclosed building conversational system adopts " 3+n " line cable 2 as the wire rod of signal transmission, and the signal definition that every line transmits in " 3+n " line cable 2 is as follows: the signals of 3 common wires 21,23,24 transmission are respectively audio signal B and the ground GND of doorway machine 1 to the audio signal A of indoor set 3, indoor set 3 to doorway machine 1; The signal of n root minute family line 22 transmission then be each household independently doorway machine 1 to the loop signal AGND of the audio signal of indoor set 3, the loop signal of corresponding 1~n family indoor set 3 be respectively AGND_1, AGND_2 ..., AGND_n, as shown in Figure 1.Each hands-free indoor set 3 links to each other with hands-free doorway machine 1 by 4 heart yearns.If one has 16 families in the unit, then the wire rod of wiring need adopt " 3+16 ", i.e. the cable of 19 cores.
Below the specific works process of present embodiment is described respectively.
Call out:
Hands-free doorway machine 1 in the present embodiment is when standby, detect the touch-call action of keyboard 120 by MCU and I/O expanded circuit 121 after, minute family line AGND of the control minute hands-free indoor set 3 of the corresponding called of family gating circuit 116 gatings, and control the tinkle of bells circuit for generating 110 produces ringing tone, output after audio power amplifier circuit 115 amplifies, a-signal line through " 3+n " line cable transfers to called hands-free indoor set 3, after straight, deliver to loudspeaker 31 through the state control circuit 37 of hands-free indoor set 3 again, again through a minute family line AGND, turn back to minute family gating circuit 116 of doorway machine 1, because being strobed by the AGND of hands-free indoor set 3 correspondences of being exhaled, and the AGND of other indoor set 3 gating not, so only have the hands-free indoor set 3 of being exhaled to send ringing tone, and ringing tone can not occur in other hands-free indoor set 3.Hands-free doorway machine 1 is when sending ringing tone, and its MCU and I/O expanded circuit 121 control dc bias circuits 16 are sent a dc offset voltage Vbias1 to the a-signal line.The state control circuit 37 that this dc offset voltage Vbias1 controls hands-free indoor set 3 is in ringing condition, at this moment, microphone amplifying circuit switch 38 is in open-circuit condition, and microphone audio amplifying circuit 33 just is in closed condition, and namely the microphone 32 of indoor set 3 is in mute state.Simultaneously, talking state indicator light 34 is in and extinguishes state.
Dc bias circuit:
Dc bias circuit 16 in the hands-free doorway machine 1 in the present embodiment provides two kinds of dc offset voltage Vbias1 and Vbias2 to the a-signal line, and Vbias2 voltage is higher than Vbias1.Vbias1 controls called hands-free indoor set 3 and is in ringing condition, and under this state, talking state indicator light 34 extinguishes.Be in talking state and Vbias2 controls called hands-free indoor set 3, under this state, talking state indicator light 34 is lighted.Vbias1 and Vbias2 can not affect the holding state of other not called hands-free indoor set 3.
Dc bias circuit 16 in the hands-free doorway machine 1 also provides a dc offset voltage Vbias3 to the B holding wire always, this dc offset voltage Vbias3 powers to the microphone audio amplifying circuit 33 of the hands-free indoor set 3 that is in talking state on the one hand, unlock key 36 to the hands-free indoor set 3 that is in talking state provides a bias voltage on the other hand, so that the level sensitive circuit 14 of doorway machine 1 detects the actuation of keys of unlock key 36.
Conversation:
When hands-free indoor set 3 is in ringing condition, clicking it plucks/on-hook button 35, to the dc offset voltage VbiasA on the a-signal line be dragged down, MCU in this moment doorway machine 1 and I/O expanded circuit 121 can detect indoor set 3 by level sensitive circuit 14 actuation of keys, then control is closed the tinkle of bells circuit for generating 110, is opened echo elimination or automatic half-duplex audio communication circuit 113, and control dc bias circuit 16 is to more high-tension dc offset voltage Vbias2 of a-signal line output.This moment, microphone 111 audio signal of picking up of doorway machine 1 was eliminated or automatically behind half-duplex audio communication circuit 113, the audio power amplifier circuit 115 through echo, deliver to indoor set 3 through the a-signal line, deliver to loudspeaker 31 through the state control circuit 37 of indoor set 3 after straight again and play back.Dc offset voltage Vbias2 with doorway machine 1 to the audio signal of indoor set 3 together after the a-signal line is delivered to indoor set 3, the state control circuit 37 of controlling hands-free indoor set 3 enters talking state, this moment, the microphone amplifying circuit switch 38 of indoor set 3 was in short-circuit condition, microphone audio amplifying circuit 33 is just in running order, be that the audio signal that the microphone 32 of indoor set 3 picks up outputs to the B holding wire after microphone audio amplifying circuit 33 amplifies, deliver to doorway machine 1 by cable, eliminate or automatic half-duplex audio communication circuit 113 through echo, behind the audio power amplifier circuit 114, play back by loudspeaker 112.Like this, just can carry out hands-free duplex between hands-free doorway machine 1 and the hands-free indoor set 3 has conversed.Under talking state, the talking state indicator light 34 of indoor set is in illuminating state, and indicating user indoor set 3 is in talking state at this moment.
Under talking state, if doorway machine 1 detects the plucking of the end telephone operation of keyboard 120 or indoor set 3/on-hook key actuation of keys or converses overtime, the MCU of doorway machine 1 and I/O expanded circuit 121 are closed control echo elimination or automatic half-duplex audio communication circuit 113, are closed all paths in minute family gating circuit 116, and control dc bias circuit output Vbias1.Hands-free indoor set 3 will turn back to holding state this moment.
Hands-free doorway machine 1 and called hands-free indoor set 3 are when conversation, the AGND signal of minute 116 called hands-free indoor sets 3 of gating of family gating circuit of hands-free doorway machine 1, the AGND signal of other hands-free indoor set 3 of gating no longer, so just guaranteed to converse and between both sides, carried out, and other hands-free indoor set 3 is not strobed because of its AGND signal, state control circuit 37 is closed, be that these indoor sets 3 are in holding state, its microphone amplifying circuit switch 38 is in open-circuit condition, namely being equivalent to microphone is muted, do not send audio signal to the B holding wire, thereby can not disturb the normal talking of both call sides.
Unblank:
Under talking state, the MCU of hands-free doorway machine 1 and I/O expanded circuit 121 detect on the B holding wire direct current biasing Vbias3 by level sensitive circuit 14 and are pressed by the unlock key 36 of the hands-free indoor set 3 under the talking state and drag down, at this moment, MCU and I/O expanded circuit 121 are controlled the control circuit 13 output unlocking signals of unblanking, realization is to the control of unblanking of the locksets such as electric control lock or magnetic key operated lock, like this, resident family just can be the visiting guest and opens the gate, unit.
Similarly, since other hands-free indoor set 3 because AGND is not strobed, even press the control action of unblanking that its unlock key 36 can not cause hands-free doorway machine 1 yet.
It is worthy of note that the hands-free doorway machine 1 in the present embodiment can increase LED charactron or LCD display etc., to show user interface information, as calling out resident family's room number, unlocking condition etc.; Also can be combined with gate inhibition's technology such as ID/IC card or fingerprints, form the hands-free doorway machine with corresponding gate function.
Please refer to again shown in Figure 4ly, be the circuit diagram of the hands-free doorway machine 1 in the present embodiment, below emphatically to the audio interface circuit in the hands-free doorway machine 1, comprise that a minute family gating circuit 116, dc bias circuit 16 and level sensitive circuit 14 etc. describe.
Base resistance R10, NPN triode Q2, current-limiting resistance R8 and voltage-stabiliser tube D3 consist of one tunnel minute family gating circuit 116, concrete connected mode is: an end of resistance R 10 is connected with the gating control end of MCU and I/O expanded circuit 121, and the other end is connected to the base stage of triode Q2; The collector electrode of triode Q2 is connected to AGND_1 in the 3+n line interface 15, grounded emitter via resistance R 8; Voltage-stabiliser tube D3 forward is connected between the collector electrode and emitter of triode Q2; Wherein 8 metering functions of resistance R, voltage-stabiliser tube D3 work the backward channel of protecting triode Q2 and AC signal being provided; When MCU and I/O expanded circuit 121 are high level to its control inputs, corresponding this minute family gating circuit 116 gatings, a-signal (comprising bell signal and call voice signal) just with this minute family gating circuit 116 as the loop; MCU and I/O expanded circuit 121 guarantee that other minute family gating circuit 116 is not strobed when the gating circuit 116 of a certain minute family of gating; Every hands-free indoor set 3 all has one tunnel minute family gating circuit 116 of independent correspondence in hands-free doorway machine 1, its circuit is all identical, as shown in Figure 4 R18, the R14, Q3 and the D5 that are connected with interface AGND_2, R23, the R21, Q6 and the D6...... that are connected with interface AGND_n do not repeat them here.
In addition, in the present embodiment, dc bias circuit 16 comprises a NPN triode Q8, a PNP triode Q7, three resistance R 27, R28, R29 and diode D7, D8; The base stage of triode Q8 is connected with the voltage controling end of MCU and I/O expanded circuit 121 by resistance R 27, grounded emitter, and collector electrode is connected to the base stage of triode Q7 by resistance R 27; The base stage of triode Q7 also is connected to emitter by resistance R 28, and connects bias voltage Vbias2 by this emitter; Diode D8, the resistance R 3 that the collector electrode of triode Q7 connects by forward is connected to the interface A in the 3+n line interface; And aforementioned interface A also connects bias voltage Vbias1 by the diode D7 of resistance R 3, an Opposite direction connection.
Vbias1 gets+8V in this embodiment, and Vbias2 gets+15V, and resistance R 3 is got 560 Ω.When holding state or ringing condition, triode Q7 controls it by MCU and I/O expanded circuit 121 and is in cut-off state, at this moment, VbiasA=Vbias1, namely Vbias1 provides dc offset voltage for the a-signal line through diode D7, resistance R 3.When ringing condition, press the plucking/on-hook key 35 of hands-free indoor set 3 of ring, the dc offset voltage of a-signal line will be pulled to about 1/3 Vbias1 from about Vbias1, the comparison reference voltage Vref1 of comparator U2A is arranged on about 1/2 Vbias1, at this moment, MCU and I/O expanded circuit 121 can detect this by comparator U2A and pluck/on-hook key 35 actions, and control system enters talking state.When talking state, triode Q7 controls it by MCU and I/O expanded circuit 121 and is in conducting state, at this moment, and VbiasA=Vbias2, be that Vbias2 provides dc offset voltage through triode Q7, diode D8, resistance R 3 to the a-signal line, and diode D7 is in cut-off state.When talking state, plucking/on-hook key 35 of the hands-free indoor set 3 of press-to-talk, the dc offset voltage of a-signal line will be pulled to about 1/3 Vbias2 from about Vbias2, at this moment, MCU and I/O expanded circuit 121 can detect this by comparator U2A and pluck/on-hook key 35 actions, and control system end conversation, turn back to holding state.
Bias voltage VbiasA also plays the effect that dc offset voltage is provided to minute family gating circuit 116, to guarantee that the triode (such as Q2) in minute family gating circuit 116 can the conducting of saturated ground.Resistance R 4 (as shown in Figure 5), the AGND holding wire of VbiasA in resistance R 3, a-signal line, hands-free indoor set 3 arrives a minute family gating circuit 116, supplies with its dc offset voltage.
And bias voltage Vbias3 directly provides dc offset voltage for the B holding wire by resistance R 26, and Vbias3 gets+8V in this embodiment, and voltage R26 gets 1K Ω.Vbias3 provides power supply on the one hand the microphone audio amplifying circuit 33 of hands-free indoor set 1, provides on the other hand unlock key 36 and draws power supply.When talking state, the unlock key 36 of the hands-free indoor set 3 of press-to-talk, dc offset voltage on the B holding wire will be connect from about 1/2 Vbias3 is low to moderate 1/10 Vbias3, the comparison reference voltage Vref2 of comparator U2B is arranged on about 1/3Vbias3, at this moment, MCU and I/O expanded circuit 121 can detect this actuation of keys by comparator U2B, and control hands-free doorway machine 1 and carry out unlocking action.
Do not express in detail the structure of the control circuit 13 of unblanking common in the intercom system, the tinkle of bells circuit for generating 110, keyboard 120, audio power amplifier circuit 115, echo elimination or automatic half-duplex audio communication circuit 113 in the embodiment circuit diagram of hands-free doorway machine 1 (with reference to figure 4); Wherein, the unblank general release of adopting a triode control relay of control circuit 13 and adhesive controlled and unblanked, the tinkle of bells circuit for generating 110 general the tinkle of bells generating chips of special use that adopt are realized, and echo elimination can adopt special-purpose voice dsp to realize, automatically the half-duplex audio communication circuit then can adopt MC34118 to realize, audio power amplifier circuit 115 can adopt the general power amplifiers such as LM386, and keyboard 120 can adopt the I/O scan mode to realize.More than these circuit be more common circuit, no longer be described in more detail in this realization to these circuit.
Be illustrated in figure 5 as the detailed circuit diagram of hands-free indoor set 3 among the present invention, wherein resistance R 4 is connected between a-signal line and the AGND holding wire, dc offset voltage is provided for minute family gating circuit 116 of hands-free doorway machine 1; 1 of capacitor C is to play before loudspeaker 31 every straight effect; SW1 plucks/touch-switch of on-hook key 35, and resistance R 1 plays current limliting and dividing potential drop when SW1 presses, with the contact of protection SW1 and guarantee that the unlikely mistake of dc offset voltage on the a-signal line is low and cause the distortion of the tinkle of bells or conversation audio signal.The tinkle of bells directly plays back by loudspeaker 31 after straight through electrochemical capacitor C1 after dividing accordingly family gating circuit 116 with the conversation audio signal from hands-free doorway machine 1 gating.
Resistance R 2 then provides power supply and state input to the state control circuit 37 that is made of resistance R 7, triode Q1, voltage-stabiliser tube D1, resistance R 6, light-emitting diode D2 with the RC network that capacitor C 2 consists of, and wherein D1 selects the voltage-stabiliser tube of 7.5V.When holding state, because AGND is not divided family gating circuit 116 gatings, state control circuit 37 is not worked, and talking state indicator light D2 extinguishes, as the Q5 cut-off of microphone audio amplifying circuit 33 switches; When ringing condition, because of input less than+8V (voltage of Vbias1), triode Q1 cut-off, talking state indicator light D2 extinguishes, the Q5 cut-off; When talking state, because input is about+12V (Vbias2 has some pressure drops behind R3), triode Q1 conducting, talking state indicator light D2 lights, triode Q5 conducting.
Resistance R 11 provides overvoltage protection for the microphone audio amplifying circuit 33 that is made of resistance R 12, R16, R17, triode Q4, resistance R 19, electrochemical capacitor C6, capacitor C 5 with voltage-stabiliser tube D4; SW2 is unlock key, and R11 also provides metering function when SW2 presses, with the contact of protection SW2; The RC network that R13 and C8 consist of is responsible for providing dc offset voltage to microphone 32, R20 then is the biasing circuit of microphone 32, the audio signal that microphone 32 picks up through after R20, the C7 low-pass filtering again after the high-pass filtering that C5 and 33 input impedance of microphone audio amplifying circuit consist of, amplify through amplifying circuit and to output on the B holding wire.When only having the switch Q5 conducting of microphone audio amplifying circuit 33, above circuit can be worked, and that is to say, when only having hands-free indoor set 3 to be in talking state, the audio signal that microphone 32 picks up just can obtain amplifying, and outputs on the B holding wire; Only when talking state, press unlock key 36 and could the hands-free doorway machine 1 of remote control unblank.
In sum, a kind of building conversational system of the present invention, by minute family gating circuit 116 and a dc bias circuit 16 are set, do not increasing system cost or even reducing under the prerequisite of cost, adopt hands-free indoor set 3, realize complete hands-free intercommunication conversation, for the user provides more friendly experience, realized simultaneously the in every family isolation features of the conversation that " 1+n " line wire laying mode system has, and, this system is when calling out indoor set 3, and the assignment key that only need to click doorway machine can allow indoor set 3 continue ring, and does not need to pin assignment key always.
Above embodiment only for explanation technological thought of the present invention, can not limit protection scope of the present invention with this, every technological thought that proposes according to the present invention, and any change of doing on the technical scheme basis all falls within the protection range of the present invention.