JP2009100469A - Load driving method, and load driving apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control the occurrence of a communication abnormality by protecting an alternating current signal in a transmission line superposed with direct current voltage. <P>SOLUTION: A step (a) for judging whether a load driving command has been input or not is executed (S101). A step (b) for judging whether the alternating current signal is included in input voltage or not is executed (S102) in the case that the judgment in the step (a) is positive. A processing according to the driving command is executed in the case that the judgment in the step (b) is negative, and a step (c) waiting for the processing is executed (S103) in the case that it is positive. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for transmitting an AC signal, and particularly relates to measures against fluctuations in the DC voltage when a DC voltage is superimposed.

  For example, in an air conditioner, a technique has been proposed in which a DC voltage for power supply and a transmission signal are transmitted by superimposing the DC voltage for power supply and a transmission signal on a transmission line to a remote controller (hereinafter referred to as “remote controller”). (Patent Document 1).

  In Patent Document 1, an indoor unit and a wired remote controller are connected by two transmission lines. In addition to supplying a DC voltage from the indoor unit to the wired remote controller, a baseband signal for half duplex communication between the wired remote controller and the indoor unit is also superimposed on the two transmission lines.

  Normally, the indoor unit is provided with a coil between the DC power supply and the transmission line to keep the DC voltage supplied to the wired remote control and the AC impedance between the transmission lines moderate. Current flows through this coil.

JP-A-5-175972

  In recent years, in addition to the above-described technology, there is an increasing demand for improving the visibility of display means (for example, LCD) included in a wired remote controller and mounting a backlight. However, if a backlight is simply added to the configuration disclosed in Patent Document 1 and is driven using a power supply voltage obtained based on a DC voltage supplied from the indoor unit to the remote controller, The following problems arise.

  Since the backlight consumes current, the direct current supplied from the indoor unit to the remote controller increases. Since the transmission line through which the DC current flows has a DC resistance and an inductance, a DC voltage is generated in the transmission line. When the direct current fluctuates (increases or decreases), the direct current voltage (baseline) fluctuates significantly due to the inductance. This phenomenon also occurs when the voltage supply to the load is turned off.

  FIG. 11 is a graph showing the input voltage Vi on the transmission line and the baseband signal Dout separated from the input voltage Vi on the remote control side. A broken line in the figure indicates a threshold voltage for separating the baseband signal Dout. As shown in FIG. 11, the base line of the communication baseband waveform may change. In this case, since the DC voltage fluctuates, the power supply voltage obtained based on this also decreases. When the baseband signal Dout is separated by the receiving circuit that operates based on the power supply voltage, if the fluctuation of the baseline is slow, the threshold voltage also changes following the baseline.

  However, since the transmission path of the baseband signal transmitted to the receiving circuit is different from the supply path to which the power supply voltage is supplied, if the baseline fluctuation is steep, the power supply voltage fluctuation may not follow this. is there. At this time, the threshold voltage adopted by the receiving circuit may not be able to follow according to the change in the baseline, which may cause a communication abnormality.

Considering the specific cause of communication abnormality, there are mainly the following two. That is,
(A) Transmission line length: The resistance value of the transmission line changes due to the difference in the length of the transmission line between the indoor unit and the remote control. The longer the transmission line, the greater the voltage drop;
(B) Thickness of the transmission line: As the transmission line becomes thinner, the electrical resistance increases.
The voltage drop when the load fluctuates increases.
In order to suppress this fluctuation, the inductance value on the indoor unit side coil and the remote control side can be suppressed to some extent, but the fluctuation cannot be reduced to zero due to cost, mounting space, and the like.

  Therefore, the longer the transmission line and the thinner the transmission line, the easier it is for communication abnormalities caused by the backlight to consume current.

  In view of the above problems, an object of the present invention is to provide a technique for preventing the occurrence of a communication abnormality without hindering the detection of an AC signal even when a DC voltage fluctuates due to driving of a load.

  In order to solve the above-mentioned problem, the first invention is characterized in that the communication means (102) and the DC voltage separation means (108) transmit the transmission lines (128, 129) for transmitting the input voltage in which the DC voltage and the AC voltage are superimposed. The DC voltage separating means separates the power supply voltage from the input voltage and outputs it to the communication means and the load (122). The communication means is a reference potential set based on the power supply voltage. (Vref) is used to separate the AC signal from the input voltage, and the load operates according to a drive command using the power supply voltage as an operation power supply, and (a) whether or not the load drive command is input Steps (S101) and (b) If the determination in Step (a) is affirmative, the step (S101) determines whether or not the AC signal is included in the input voltage. 102), (c) If the determination in step (b) is negative, the process (S110) corresponding to the drive command is executed, and if the determination is affirmative, the step of waiting for the process is executed. This is a load driving method.

  2nd invention is 1st invention, Comprising: When judgment in the said step (b) is affirmative, the said step (b) is further performed after execution of the said step (c).

  3rd invention is 1st or 2nd invention, Comprising: The control which makes the change of the voltage applied to the said load by the said process make a time continuous change is performed.

  4th invention is 1st or 2nd invention, Comprising: The control which makes the change of the voltage applied to the said load by the said process make a time discrete change is performed.

  In the fifth invention, the communication means (102) and the DC voltage separating means (108) are connected in parallel to the transmission lines (128, 129) for transmitting the input voltage in which the DC voltage and the AC voltage are superimposed. The DC voltage separation means separates a power supply voltage from the input voltage and outputs the power supply voltage to the communication means and the load (122). The communication means uses the reference potential (Vref) set with the power supply voltage as a reference. A load driving device (100) for separating the AC signal from an input voltage and driving the load according to a drive command using the power supply voltage as an operation power supply; and an input means (118) for receiving an input of the load drive command; Monitoring means (126) for monitoring whether or not the AC voltage is included in the input voltage when the input means receives the drive command; and the AC voltage in the input voltage Control means (124) which performs processing according to the drive command when no signal is included, and waits for the processing when the AC signal is included in the input voltage It is.

  In the sixth invention, the communication means (102) and the DC voltage separating means (108) are connected in parallel to the transmission lines (128, 129) for transmitting the input voltage in which the DC voltage and the AC signal are superimposed. The DC voltage separation means separates a power supply voltage from the input voltage and outputs the power supply voltage to the communication means and the load (122). The communication means uses the reference potential (Vref) set with the power supply voltage as a reference. Separating the AC signal from an input voltage, and the load operates according to a drive command using the power supply voltage as an operation power source, and (a) determining whether the drive command is input (S201), (B) In the load driving method, when the determination in step (a) is affirmative, the step (S202) of changing the power supply voltage with time is executed.

  7th invention is 6th invention, Comprising: In the said step (b), the said power supply voltage is continuously changed over time.

  8th invention is 6th invention, Comprising: In the said step (b), the said power supply voltage is discretely changed in time.

  In the ninth invention, the communication means (102) and the DC voltage separating means (108) are connected in parallel to the transmission lines (128, 129) for transmitting the input voltage on which the DC voltage and the AC signal are superimposed. The DC voltage separation means separates a power supply voltage from the input voltage and outputs the power supply voltage to the communication means and the load (122). The communication means uses the reference potential (Vref) set based on the power supply voltage. One AC signal is separated from an input voltage, and the load operates according to a drive command using the power supply voltage as an operation power supply, and (b) an output command for outputting the other AC signal to the transmission line. Step (S301) for determining whether or not it has been received (b) This step is executed when the determination in Step (A) is affirmative, and it is determined whether or not the one AC signal is included in the input voltage. Steps (S302), (c) Steps (S303), (d) executed when the determination in Step (a) is affirmative and determining whether or not the drive command is input. ), When the determination in (c) is negative, the output of the other AC signal to the transmission line is executed based on the output command, and at least one is positive Is a load driving method in which the steps of waiting for the output (S302, S303) are executed.

  A tenth aspect of the invention is the ninth aspect of the invention, and when the judgment in the step (b) is negative, the steps (c), (d) until the judgment in the step (c) becomes negative. ) Repeatedly.

  The eleventh aspect of the invention is the ninth aspect of the invention, in which (e) when the judgment in step (c) is affirmative, the rate of change of the DC voltage is monitored and the rate of change is determined in advance. The step of executing the output (S304, S305) is executed when the value is below the threshold value.

  A twelfth aspect of the invention is any one of the ninth to eleventh aspects of the invention, and when the determination in the step (c) is affirmative, processing according to the drive command is executed.

  In a thirteenth aspect, the communication means (102) and the DC voltage separating means (108) are connected in parallel to the transmission lines (128, 129) for transmitting the input voltage on which the DC voltage and the AC signal are superimposed. The DC voltage separation means separates a power supply voltage from the input voltage and outputs the power supply voltage to the communication means and the load (122). The communication means uses the reference potential (Vref) set with the power supply voltage as a reference. A load driving device (100B) that separates the AC signal from an input voltage and drives the load according to a driving command using the power supply voltage as an operation power source, and outputs an AC command to the transmission line. Input means (118B) for receiving, and first monitoring means (126B) for monitoring whether or not the drive command is input when the input means receives the output command; Second monitoring means (226B) for monitoring whether or not the other AC signal is separated from the transmission line, and when the drive command is not input and the other AC signal is not separated Control means for executing the output of the one AC signal to the output line according to the output command, and waiting for the output when the drive command is input or the other AC signal is separated ( 124B).

  A fourteenth aspect of the invention is the thirteenth aspect of the invention, wherein when the first monitoring means (126B) determines that the load is being driven, a third monitoring means for monitoring the rate of change of the DC voltage ( 326B), the control means (124B) executes the output when the rate of change is less than or equal to a predetermined threshold, and the control means (124B) when the rate of change is greater than a predetermined threshold. Wait for output.

  According to the first invention, fluctuations in the DC voltage caused by driving the load do not hinder the detection of the AC signal.

  According to the second aspect of the present invention, it is possible to execute the standby processing so as not to prevent the detection of the AC signal.

  According to the third aspect of the invention, it is possible to avoid or suppress communication abnormality due to fluctuations in the power supply voltage without disturbing detection of the AC signal.

  According to the fourth invention, it is possible to avoid or suppress communication abnormality due to fluctuations in the power supply voltage at a lower cost than in the third invention without hindering detection of the AC signal.

  According to the fifth aspect of the invention, fluctuations in the DC voltage caused by driving the load do not hinder the detection of the AC signal.

  According to the sixth aspect, it is possible to follow the fluctuation of the threshold voltage with the fluctuation of the threshold voltage, and avoid or suppress the occurrence of the communication abnormality.

  According to the seventh aspect, it is possible to avoid or suppress communication abnormality due to fluctuations in the power supply voltage.

  According to the eighth invention, communication abnormality due to fluctuations in the power supply voltage can be avoided or suppressed at low cost.

  According to the ninth aspect of the invention, the load can be driven quickly without disturbing the detection of other AC signals by fluctuations in the DC voltage caused by driving the load.

  According to the tenth aspect of the invention, it is possible to execute the standby output so as not to disturb the drive of the load.

  According to the eleventh aspect of the invention, an AC signal can be detected even when a DC voltage fluctuates due to driving of a load.

  According to the twelfth aspect, the load can be driven quickly.

  According to the thirteenth invention, the load can be driven promptly without fluctuations in the DC voltage caused by driving the load hindering detection of other AC signals.

  According to the fourteenth aspect, an AC signal can be detected even if a DC voltage fluctuates due to driving of a load.

  Preferred embodiments of the present invention will be described below with reference to the drawings. In the following drawings including FIG. 1, only elements related to the present invention are shown.

<First Embodiment>
<Constitution>
FIG. 1 is a diagram showing a load driving device (remote control) 100 according to the first embodiment of the present invention. As shown in FIG. 1, the remote controller 100 of this embodiment is connected to the indoor unit side I / F circuit 130 of an air conditioner via transmission lines 128 and 129, for example.

  The indoor unit side I / F circuit 130 includes a communication unit 132 having a transmission circuit 134 and a reception circuit 136, and a DC voltage superposition circuit 138 having a power supply 140 and a coil 142.

  The remote controller 100 receives an input operation (for example, setting of the operation of the air conditioner or an input of a driving command for the backlight 122) from a user and outputs an input operation signal, a display unit (LCD) 120, The backlight unit 122 of the LCD 120 and an MCU 124 for controlling the operation of the air conditioner based on input operation signals from the input circuit 118 and controlling the LCD 120 and the backlight unit 122 are provided.

  In remote controller 100, communication unit 102 and DC voltage separation circuit 108 are connected in parallel to transmission lines 128 and 129 that transmit an input voltage in which a DC voltage and an AC signal are superimposed. The DC voltage separation circuit 108 separates the power supply voltage from the input voltage and outputs it to the communication unit 102 and the load (backlight) 122. The communication unit 102 includes a reception circuit 104 and a transmission circuit 106. For example, the transmission circuit 106 transmits control of the operation of the air conditioner from the MCU 124 to an indoor unit (not shown). The receiving circuit 104 separates the AC signal from the input voltage using a reference potential Vref (not shown in FIG. 1) set with the power supply voltage as a reference.

  In addition, the remote controller 100 drives the backlight 122 directly under the control of the MCU 124 in accordance with the input drive command using the power supply voltage supplied from the power supply circuit 116 as an operation power supply (hereinafter referred to as “lighting”). Or “off”).

  FIG. 2 is a circuit diagram showing the inside of the receiving circuit 104. The reception circuit 136 provided in the indoor unit side I / F circuit 130 is the same, but only the reception circuit 104 of the remote controller 100 will be described here. The receiving circuit 104 extracts an AC signal from the transmission lines 128 and 129 on which a DC voltage is superimposed. Specifically, a baseband signal is extracted from the input P1 from the transmission line 128 and the input P2 from the transmission line 129 by the high-pass filter 202 having capacitors C1, C2 and resistors R1, R2, R3, R4. That is, the high pass filter 202 removes the DC voltage.

  The extracted baseband signal is input as an input In1 and an input In2 to a differential amplifier circuit 204 having amplifiers Q1 and Q2 commonly connected to a constant current circuit I1. Then, the differential voltage between the input In1 and the input In2 is amplified and output as the differential voltages Vr5 and Vr6 to the load resistor R5 and the load resistor R6.

  The output difference voltages Vr5 and Vr6 are compared with the reference potential Vref in the comparators U1 and U2, and when Vr5 <Vref, the comparator U1 outputs an L level output. When Vr6 <Vref, the comparator U2 outputs an L level output. Since the OR gate U4 functions as a logical product gate of negative logic, if any of the outputs is L level in response to the outputs of the comparators U1 and U2, the output Vout is set to L level and transmitted to the MCU 124.

  In this embodiment, communication is performed using an AMI signal (Alternate Mark Inversion code), and 0 and 1 are expressed by voltage polarity, so it is necessary to determine whether the signal is positive or negative. Therefore, a pair of comparators U1 and U2 are provided.

  Returning to FIG. 1, the DC voltage separation circuit 108 includes a coil 110, a diode bridge 112, and an electrolytic capacitor 114. The DC voltage is rectified by the diode bridge 112, smoothed by the electrolytic capacitor 114, and the DC voltage is supplied to the power supply circuit 116. To send.

  The power supply circuit 116 generates an operating voltage based on the DC voltage obtained from the electrolytic capacitor 114 (the DC voltage itself may be adopted as the operating voltage), and supplies the operating voltage to the receiving circuit 104 and the transmitting circuit 106. At the same time, a voltage is applied to the backlight 122.

  FIG. 3 is a diagram for explaining a load driving method. The MCU 124 has a monitoring unit 126. When the input circuit 118 receives a drive command, the monitoring unit 126 monitors whether or not an AC signal is included in the input voltage input from the transmission lines 128 and 129. Such monitoring can be realized by detecting the output Vout of the OR gate U4. The MCU 124 executes processing according to the drive command when the input voltage to the receiving circuit 104 does not include an AC signal, and waits for the processing when the input voltage includes an AC signal.

  Specifically, as shown in FIG. 3, when the input circuit 118 receives a drive command, the monitoring unit 126 monitors whether or not the transmission lines 128 and 129 include an AC signal communication packet. When no communication packet is included (resting period), the backlight 122 is controlled to adjust the voltage consumed by the backlight 122 to control lighting or extinguishing. In other words, while communication is performed between the remote controller 100 and the indoor unit side I / F circuit 130, the backlight 122 is turned on or off.

  Further, even when the backlight 122 is being turned on or off, it is monitored whether or not the transmission line 128, 129 contains a communication packet, and if a communication packet is contained, The control of turning on or off the backlight 122 is interrupted, and the control is resumed during the suspension period. Thereby, the influence which the voltage fluctuation accompanying supply of the operating voltage to the backlight 122 has on the communication between the remote controller 100 and the indoor unit side I / F circuit 130 can be avoided or suppressed.

  FIG. 4 is a diagram illustrating a voltage waveform related to driving of the backlight 122. The change in the voltage applied to the backlight 122 by the process performed by the MCU 124 may be a time-continuous change as shown in FIG. 4A or a time-discrete change as shown in FIG. It may be a change. For example, when the change in the voltage applied to the backlight 122 is made discrete in time, the duty of the pulse is changed as follows. That is, when the backlight 122 (load) is turned on, the duty of the pulse voltage is increased with time, and when the backlight 122 (load) is turned off, the duty of the pulse voltage is decreased with time.

<Time constant and voltage fluctuation of high-pass filter>
FIG. 5 is a diagram showing voltage fluctuations, and FIG. 6 is a diagram showing waveforms of the transmission lines 128 and 129. Here, the time constant and voltage fluctuation of the high-pass filter 202 will be described.

  When the potential difference Vin1−Vin2 between the input In1 and the input In2 (see FIG. 2) is equal to or greater than a predetermined voltage threshold, the receiving circuit 104 outputs an L level output Vout.

  Consider a state in which no AC signal is superimposed. When the DC voltage Vp1−p2 is applied between the inputs P1 and P2, the relational expression Vp1−p2 = Vc1 + Vc2 is established using the interelectrode voltage Vc1 and Vc2 of the capacitors C1 and C2. Here, when the DC voltage superimposed between the transmission lines 128 and 129 decreases, the voltage Vc1 + Vc2 also decreases. Further, since the voltage applied to the power supply circuit 116 by the DC voltage separation circuit 108 is also reduced, the power supply voltage Vcc that is supplied from the power supply circuit 116 to the receiving circuit 104 is also reduced by ΔVcc. Therefore, if the decrease amount of the voltage Vc1 is ΔVc1 and the decrease amount of the voltage Vc2 is ΔVc2, the potential difference between the inputs In1 and In2 decreases in proportion to (ΔVcc−ΔVc1−ΔVc2).

  As the voltage Vp1-p2 decreases due to the fluctuation of the DC voltage, the inter-electrode voltages Vc1, Vc2 of the capacitors C1, C2 decrease. The potential difference Vin1−Vin2 = 0 between In1 and In2 is maintained. However, when the DC voltage fluctuates rapidly, Vin1−Vin2 ≠ 0 due to the discharge of the capacitors C1 and C2. In this case, as shown in FIG. 5, the baseline is lowered, and the negative threshold voltage is relatively raised. In the present invention, rapid fluctuations in the DC voltage are suppressed by driving the backlight 122 during the pause period of packet communication.

  Instead of suppressing the rapid fluctuation of the DC voltage, the voltage fluctuation is achieved by appropriately adjusting the response speed to the fluctuation, that is, the capacitances of the capacitors C1 and C2 and the resistance values of the resistors R1 to R4 to reduce the time constant. Can follow. However, if the time constant is made small enough to follow a rapid voltage fluctuation, a droop occurs in the baseband waveform and the amplitude at the AC signal reading point becomes insufficient. Therefore, it is desirable to suppress rapid voltage fluctuations as shown in the present invention.

  The difference voltage between the voltage Vr5, Vr6 and the reference potential Vref after being dropped by the resistors R5, R6 connected to the power supply Vcc is set as the positive threshold voltage and the negative threshold voltage, and the signal exceeds the positive threshold voltage. Alternatively, a signal lower than the negative threshold voltage is sent as an output L to the MCU 124. The MCU 124 communicates with the indoor unit side I / F circuit 130 based on the output L sent from the receiving circuit 104.

<Operation>
FIG. 7 is a flowchart illustrating a method for driving the load (backlight 122). The remote controller 100 performs the following operations by having the above-described configuration. In this flowchart, only the operation for the remote controller 100 to drive the backlight 122 is shown, and illustration and description of other processing operations are omitted. Further, unless otherwise specified, a series of processing operations in the remote controller 100 are automatically performed under the control of the MCU 124. In this embodiment, the lighting process of the backlight 122 will be described as a specific example. However, the same process can be executed for the backlight 122 extinguishing process. Shall be read as “decrease voltage”.

  First, the remote controller 100 stands by until the drive command for the backlight 122 is input from the input circuit 118 while the power is on (step S101). When the drive command for the backlight 122 is input, Yes (denoted as “Y” in the figure: the same applies hereinafter) is selected in step S101, and the monitoring unit 126 transmits an AC signal to the transmission lines 128 and 129. If the determination is affirmative (that is, if an AC signal is transmitted to the transmission lines 128 and 129), the MCU 124 waits for the driving process of the backlight 122 (step S102). ).

  If the determination by the monitoring unit 126 is negative (that is, no AC signal is transmitted to the transmission lines 128 and 129), the MCU 124 controls the power supply circuit 116 to turn on the backlight 122. The voltage application is started gradually. That is, the voltage of the transmission lines 128 and 129 is gradually increased (step S103).

  Even during the process of step S103, the monitoring unit 126 monitors whether or not an AC signal is transmitted to the transmission lines 128 and 129 (step S104). If Yes is selected, the voltage to the backlight 122 is monitored. The application is interrupted (step S105). Thereafter, the above process is repeated until the lighting process of the backlight 122 is completed (step S106). That is, steps S103 to S106 are grasped as step S110 as a means for solving the problem.

<Effects of First Embodiment>
As described above, by performing the lighting process of the backlight 122 during the AC signal pause period, the fluctuation of the DC voltage due to the driving of the backlight 122 does not hinder the detection of the AC signal.

  Even during the lighting process of the backlight 122, since it is monitored whether or not an AC signal is transmitted, it is possible to execute a standby process so as not to prevent detection of the AC signal.

  In addition, since the voltage applied to the backlight 122 by the lighting process is changed continuously or discretely in time, detection of an AC signal is not hindered, and communication abnormality due to fluctuations in power supply voltage is avoided or suppressed. it can. In particular, time-discrete control can be realized at a lower cost than when time-continuous control is performed.

Second Embodiment
In the above-described embodiment, the aspect in which the driving process is executed during the AC signal pause period has been described, but the present invention is not limited to this. Here, as a second embodiment of the present invention, a mode in which a power supply voltage for driving a load is temporally changed regardless of the presence or absence of an AC signal will be described with reference to the drawings. Unless otherwise specified, elements having the same functions as those in the above embodiment are denoted by the same reference numerals and description thereof is omitted.

<Constitution>
FIG. 8 is a diagram illustrating a load driving device (remote controller) 100A according to the second embodiment of the present invention, and FIG. 9 is a diagram illustrating voltage waveforms related to driving of the backlight 122. As shown in FIG. 8, the remote controller 100A of this embodiment has a configuration in which the monitoring unit 126 is removed from the above embodiment.

  When the input circuit 118 accepts a drive command, the MCU 124A controls the power supply circuit 116 to change the operating voltage to the backlight 122 over time. Specifically, as shown in FIG. 9A, the voltage applied to the backlight 122 is continuously changed over time, or is applied to the backlight 122 as shown in FIG. 9B. The backlight 122 is turned on by changing the voltage discretely in time. In this embodiment, an LED is used as the light source of the backlight 122. Since the voltage / current characteristics of the LED are nonlinear, the control performed by the MCU 124A is preferably the current control method rather than the voltage control method.

<Operation>
FIG. 10 is a flowchart illustrating a method for driving the load (backlight 122). The remote controller 100A performs the following operation by providing the above configuration. Also in this flowchart, only the operation for the remote controller 100A to drive the backlight 122 is shown, and illustration and description of other processing operations are omitted. Further, unless otherwise specified, a series of processing operations in the remote controller 100A are automatically performed under the control of the MCU 124A.

  First, the remote controller 100A waits until a drive command for the backlight 122 is input from the input circuit 118 while the power is on (step S201). When the drive command for the backlight 122 is input, “Yes” is selected in step S201, and the MCU 124A controls the power supply circuit 116 to apply the voltage to the backlight 122 either continuously or discretely (step S202). .

<Effects of Second Embodiment>
As described above, by changing the voltage application to the backlight 122 with time, fluctuations in the positive threshold voltage and the negative threshold voltage can follow the fluctuation in the baseline, thereby avoiding or suppressing the occurrence of communication abnormality. it can.

  Moreover, since the change in the voltage applied to the backlight 122 by the lighting process is a time-continuous or time-dependent change, it is possible to avoid or suppress communication abnormality due to fluctuations in the power supply voltage. In particular, by making the voltage change discrete in time, the same effect can be obtained at a lower cost than in the case of making the time continuous change.

<Third Embodiment>
In the first embodiment, the aspect in which the driving process is executed during the AC signal pause period is described. In the second embodiment, the aspect in which the driving process is executed without preventing the detection of the AC signal has been described. That is, in the first and second embodiments, the aspect in which the AC signal is prioritized over the driving process has been described, but the present invention is not limited to this. Here, as a third embodiment of the present invention, a mode in which execution of drive processing is prioritized over detection of an AC signal will be described with reference to the drawings. In the present embodiment, unless otherwise specified, elements having the same functions as those in the above embodiment are denoted by the same reference numerals and description thereof is omitted.

<Constitution>
FIG. 12 is a diagram showing a load driving device (remote control) 100B according to the third embodiment of the present invention, and FIG. 13 is a diagram for explaining a load driving method. As shown in FIG. 12, the remote controller 100B of the present embodiment has substantially the same configuration as that of the first embodiment.

  The input circuit 118 receives an output command for outputting an AC signal to the transmission lines 128 and 129. Specifically, a command for superimposing an AC signal on a DC voltage and transmitting it to the indoor unit side I / F circuit 130 is accepted. More specifically, the AC signal output to the indoor unit side I / F circuit 130 is a communication packet for controlling the operation of the air conditioner.

  When the input circuit 118 receives an output command, the first monitoring unit 126B monitors whether a drive command for the backlight 122 is input. The determination as to whether or not the drive command for the backlight 122 is input is made based on whether or not the DC voltage (baseline) flowing through the transmission lines 128 and 129 is fluctuating, for example. This is because if the DC voltage is increased, the backlight 122 is turned on accordingly, and if the DC voltage is reduced, the backlight 122 is turned off accordingly. Note that the backlight 122 may be directly monitored and a determination may be made based on whether or not a voltage is applied to the backlight 122 and the voltage is fluctuating.

  The MCU 124B executes input / output of an AC signal when the backlight 122 driving command is not input, and waits for the AC signal input / output when the backlight 122 driving command is input.

  Specifically, as shown in FIG. 13, when the input circuit 118 receives an AC signal output command, the first monitoring unit 126B monitors whether the backlight 122 driving command is input, When a drive command is not input, communication is performed by superimposing an AC signal on a DC voltage, and processing corresponding to the external AC signal is executed. In other words, while the remote controller 100B is turning on or off the backlight 122, communication between the remote controller 100B and the indoor unit side I / F circuit 130 is waited.

  The second monitoring unit 226B determines whether or not the AC signal from the indoor unit side I / F circuit 130 is separated from the transmission lines 128 and 129, that is, the AC signal from the indoor unit side I / F circuit 130 is the transmission line. 128 and 129 are monitored.

  The MCU 124B executes input / output of an AC signal when the backlight 122 driving command is not input, and waits for the AC signal input / output when the backlight 122 driving command is input.

  It is monitored whether the driving process is being executed even during the communication between the remote controller 100B and the indoor unit side I / F circuit 130, and when the driving process is started, the remote controller Communication between 100B and the indoor unit side I / F circuit 130 is interrupted and resumed after the drive process is executed. Thereby, the backlight 122 can be driven quickly. Note that the time required for the driving process of the backlight 122 and the time required for communication between the remote controller 100B and the indoor unit side I / F circuit 130 are both about several milliseconds. There is no hindrance to the operation of the machine.

<Voltage change rate monitoring>
As described above, in the driving process of the backlight 122, voltage fluctuation occurs with the supply of the operating voltage to the backlight 122. As shown in FIG. 11, when the remote control 100B and the indoor unit side I / F circuit 130 are communicating, if the baseline (DC voltage) changes sharply, the communication receiving circuit (the above embodiment) The threshold voltage employed by the receiving circuits 104 and 136) may not be able to follow the change in the baseline. This causes a communication error.

  In other words, when the baseline voltage fluctuation is equal to or less than a predetermined threshold, it can be said that an AC signal can be detected even when the voltage is fluctuating, and communication abnormality does not occur. . Therefore, when the first monitoring unit 126B determines that the backlight 122 driving command is input, the backlight 122 driving process is further provided by further including a third monitoring unit 326B that monitors the rate of change of the DC voltage. And AC signal can be output simultaneously.

  Specifically, for example, as shown in FIG. 12, the MCU 124B has a third monitoring unit 326B, and the third monitoring unit 126B determines that the driving instruction for the backlight 122 has been input. The unit 326B monitors the rate of change of the DC voltage of the transmission lines 128 and 129. Alternatively, the voltage change rate of the DC voltage may be constantly monitored, and when the first monitoring unit 126B determines that the driving process is being performed, the monitoring content may be recorded in a memory (not shown) or the like.

  When the voltage change rate monitored by the third monitoring unit 326B is equal to or lower than a predetermined threshold value (when the input voltage Vi changes, for example, as shown in FIG. 6), an AC signal is output in parallel with the execution of the driving process. Communication is performed by outputting to the transmission lines 128 and 129, and processing based on the AC signal is executed. Further, when the voltage change rate monitored by the third monitoring unit 326B is larger than the threshold (for example, when the input voltage Vi changes as shown in FIG. 11 for example), the AC processing is performed after waiting for the driving process to end. Output a signal.

  In the present embodiment, the first monitoring unit 126B that monitors the driving state of the backlight 122 and the first unit that monitors whether an AC signal is sent from the indoor unit side I / F circuit 130 to the remote controller 100B. Although the second monitoring unit 226B and the third monitoring unit 326B that monitors the voltage change rate are shown separately, they may be integrated.

<Operation>
FIG. 14 is a flowchart illustrating a method for driving a load (backlight 122). The remote controller 100B performs the following operation by providing the above configuration.

  First, the remote controller 100B stands by until an AC signal output command from the remote controller 100B to the indoor unit I / F circuit 130 is received with the power turned on (step S301). When an output command is received, Yes is selected in step S301 and whether or not an AC signal is transmitted from the indoor unit I / F circuit 130 to the remote controller 100B, that is, whether or not the AC signal is superimposed on a DC voltage. And waits until no superimposition occurs (step S302).

  When the AC signal from the indoor unit side I / F circuit 130 is not superimposed on the DC voltage, No (indicated as “N” in the figure: the same applies hereinafter) is selected in step S302, and the drive command for the backlight 122 is issued. It is monitored whether or not an input has been made (step S303). If a drive command has been input, Yes is selected in step S303 to execute the drive process (step S304), and it is monitored whether the voltage change rate related to the drive process is equal to or less than a predetermined threshold value (step S304). Step S305).

  On the other hand, when the driving process is not performed, No is selected in step S303 and an AC signal is output (step S306). Further, even when the driving process is being performed, an AC signal is output when the voltage change rate is equal to or less than the threshold value. In other words, the condition for outputting the AC signal is that the AC signal from the indoor unit side I / F circuit 130 is not superimposed and any of the following is satisfied. That is, drive processing is not performed. Or, even when the driving process is being performed, the voltage change rate is equal to or less than a threshold value.

  In the present embodiment, it is desirable that the AC signal from the indoor unit I / F circuit 130 is not superimposed while the remote controller 100B outputs the AC signal. In addition, since the driving process is performed independently of the output of the AC signal, it is desirable to interrupt the output of the AC signal as appropriate when the driving process is performed even during the output of the AC signal.

  Therefore, it is monitored whether or not a drive command is input while outputting an AC signal in step S306 (step S307).

  When a drive command is input, Yes is selected in step S307 and the drive process is executed (step S310), and it is monitored whether the voltage change rate related to the drive process is equal to or less than a threshold value (step S311). If the voltage change rate is equal to or less than the threshold value, Yes is selected in step S311 and the process proceeds to step S308. On the other hand, if the voltage change rate is larger than the threshold, No is selected in step S311 to stop the output of the AC signal (step S312). Thereafter, the process returns to step S307.

  If a drive command is not input, step S307 is executed to select No in step S307 and output an AC signal. Then, steps S306, S307, S310, S311, and S312 are repeated until the output of the AC signal is completed (step S309).

  Note that the order of the determination in step S302 and the determinations in steps S303 to S305 may be interchanged. Specifically, if the determination in step S301 is affirmative, step S303 is executed. If the determination in step S303 is negative, step S302 is executed. If the determination in step S302 is negative, no AC signal is superimposed on the transmission lines 128 and 129, and no load driving command is input as a premise that step S302 is executed ( The result of the negative determination in step S303), the process proceeds to step S306, and an AC signal is output.

  If the determination in step S303 is affirmative, steps S304 and S305 are executed. If the determination in step S305 is negative, step S303 is executed again. If the determination in step S304 is affirmative, the process proceeds to step S302 as an exceptional process of the positive determination result in step S303.

<Effect of the third embodiment>
As described above, during the driving process of the backlight 122, communication by the AC signal between the remote controller 100B and the indoor unit side I / F circuit 130 is waited, that is, the output of the AC signal is changed to the driving period of the backlight 122. Since it is performed outside, the backlight 122 can be driven quickly.

  If no AC signal is input to the remote controller 100B and the driving process is being performed, the AC signal is waited until the driving process is completed, and the AC signal is output when the driving process is completed. Since the output is performed, it is possible to execute the standby output process so as not to prevent the backlight 122 from being driven.

  In addition, since the AC signal is output when the voltage change rate is equal to or less than the threshold even during the driving process, the AC signal can be detected even if the DC voltage fluctuates due to the driving of the backlight 122. That is, the output of the AC signal and the driving process can be performed in parallel.

<Modification>
As mentioned above, although the suitable aspect of this invention was demonstrated, this invention is not limited to this. For example, the third embodiment employs a mode in which the output of the AC signal is stopped in step S312 and then the process returns to step S307. However, when the presence or absence of the drive command and the execution of the drive process are independent steps. May return to step S311 after step S312.

  FIG. 15 is a flowchart for explaining a load (backlight) driving method according to a modification, and shows a modification of the first embodiment. First, the remote controller 100 waits until a drive command for the backlight 122 is input from the input circuit 118 while the power is on (step S401). When the drive command for the backlight 122 is input, Yes is selected in step S401, and the monitoring unit 126 determines whether or not an AC signal is transmitted to the transmission lines 128 and 129, and the determination is positive. If this is the case, the MCU 124 waits for the driving process (specifically, voltage fluctuation) of the backlight 122 (step S402).

  If the determination by the monitoring unit 126 is negative, the MCU 124 controls the power supply circuit 116 to control the driving of the backlight 122 (that is, voltage fluctuation related to ON / OFF of the backlight 122) (step S403). .

It is a figure which shows the load drive device which concerns on 1st Embodiment of this invention. It is a circuit diagram which shows the inside of a receiving circuit. It is a figure explaining the drive method of load. It is a figure which shows the voltage waveform which concerns on the drive of a backlight. It is a figure which shows a voltage fluctuation. It is a figure which shows the waveform of a transmission line. It is a flowchart explaining the drive method of load. It is a figure which shows the load drive device which concerns on 2nd Embodiment of this invention. It is a figure which shows the voltage waveform which concerns on the drive of a backlight. It is a flowchart explaining the drive method of load. It is a figure which shows the transmission line waveform explaining the subject which this invention solves. It is a figure which shows the load drive device which concerns on 3rd Embodiment of this invention. It is a figure explaining the drive method of load. It is a flowchart explaining the drive method of load. It is a flowchart explaining the drive method of the load which concerns on a modification.

Explanation of symbols

100,100A remote control (load drive device)
102 Communication unit (communication means)
108 DC voltage separating means 122 Backlight (load)
124, 124A MCU (control means)
128,129 transmission line

Claims (14)

The communication means (102) and the DC voltage separating means (108) are connected in parallel to the transmission lines (128, 129) for transmitting the input voltage in which the DC voltage and the AC voltage are superimposed,
The DC voltage separating means separates a power supply voltage from the input voltage and outputs it to the communication means and the load (122),
The communication means separates the AC signal from the input voltage using a reference potential (Vref) set based on the power supply voltage,
The load is a method of operating according to a drive command using the power supply voltage as an operation power supply,
(A) a step of determining whether or not a drive command for the load has been input (S101);
(B) If the determination in step (a) is affirmative, determining whether or not the AC signal is included in the input voltage (S102);
(C) If the determination in step (b) is negative, a process (S110) corresponding to the drive command is executed, and if affirmative, a step of waiting for the process is executed. Load driving method. A load driving method according to claim 1,
If the determination in step (b) is affirmative, the step (b) is further executed after the execution of step (c). A method for driving a load according to claim 1 or 2,
A method for driving a load, wherein a control is performed to change a voltage applied to the load by the processing into a continuous change over time. A method for driving a load according to claim 1 or 2,
A method for driving a load, wherein a control is performed to change a change in voltage applied to the load by the processing into a discrete change in time. The communication means (102) and the DC voltage separating means (108) are connected in parallel to the transmission lines (128, 129) for transmitting the input voltage in which the DC voltage and the AC voltage are superimposed,
The DC voltage separating means separates a power supply voltage from the input voltage and outputs it to the communication means and the load (122),
The communication means separates the AC signal from the input voltage using a reference potential (Vref) set based on the power supply voltage,
A load driving device (100) for driving the load according to a drive command using the power supply voltage as an operation power supply,
Input means (118) for receiving an input of a drive command for the load;
Monitoring means (126) for monitoring whether or not the AC signal is included in the input voltage when the input means receives the drive command;
Control means (124) for executing a process according to the drive command when the AC voltage is not included in the input voltage and waiting for the process when the AC signal is included in the input voltage; A load driving device. The communication means (102) and the DC voltage separating means (108) are connected in parallel to the transmission lines (128, 129) for transmitting the input voltage in which the DC voltage and the AC signal are superimposed,
The DC voltage separating means separates a power supply voltage from the input voltage and outputs it to the communication means and the load (122),
The communication means separates the AC signal from the input voltage using a reference potential (Vref) set based on the power supply voltage,
The load is a method of operating according to a drive command using the power supply voltage as an operation power supply,
(A) a step of determining whether or not the drive command is input (S201);
(B) If the determination in step (a) is affirmative, step (S202) for changing the power supply voltage over time
Is executed, the load driving method. A load driving method according to claim 6,
In the step (b), a load driving method in which the power supply voltage is continuously changed over time. A load driving method according to claim 6,
In the step (b), a method for driving a load, wherein the power supply voltage is discretely changed over time. The communication means (102) and the DC voltage separating means (108) are connected in parallel to the transmission lines (128, 129) for transmitting the input voltage on which the DC voltage and the AC signal are superimposed,
The DC voltage separating means separates a power supply voltage from the input voltage and outputs it to the communication means and the load (122),
The communication means separates one AC signal from the input voltage using a reference potential (Vref) set based on the power supply voltage,
The load is a method of operating according to a drive command using the power supply voltage as an operation power supply,
(A) A step of determining whether or not an output command for outputting another AC signal to the transmission line has been received (S301).
(B) a step that is executed when the determination in step (a) is affirmative and determines whether or not the one AC signal is included in the input voltage (S302);
(C) A step (S303) that is executed when the determination in step (a) is affirmative and determines whether or not the drive command is input;
(D) If both of the determinations in steps (b) and (c) are negative, the output of the other AC signal to the transmission line is executed based on the output command, and at least one of them If one is positive, the step of waiting for the output (S302, S303)
Is executed, the load driving method. The load driving method according to claim 9, comprising:
A load driving method in which when the determination in step (b) is negative, the steps (c) and (d) are repeatedly executed until the determination in step (c) is negative. The load driving method according to claim 9, comprising:
(E) If the determination in step (c) is affirmative, the rate of change of the DC voltage is monitored, and the output is executed if the rate of change is less than or equal to a predetermined threshold (S304). , S305)
Is executed, the load driving method. A load driving method according to any one of claims 9 to 11,
If the determination in step (c) is affirmative, a load driving method is executed in which processing according to the drive command is executed. The communication means (102) and the DC voltage separating means (108) are connected in parallel to the transmission lines (128, 129) for transmitting the input voltage on which the DC voltage and the AC signal are superimposed,
The DC voltage separating means separates a power supply voltage from the input voltage and outputs it to the communication means and the load (122),
The communication means separates the AC signal from the input voltage using a reference potential (Vref) set based on the power supply voltage,
A load driving device (100B) for driving the load according to a drive command using the power supply voltage as an operation power supply,
Input means (118B) for receiving an output command for outputting one AC signal to the transmission line;
First monitoring means (126B) for monitoring whether or not the drive command is input when the input means receives the output command;
Second monitoring means (226B) for monitoring whether or not the other AC signal is separated from the transmission line;
When the drive command is not input and the other AC signal is not separated, the one AC signal is output to the output line according to the output command, and the drive command is input. Or a control means (124B) that waits for the output when the other AC signal is separated. A load driving device (100B) according to claim 13,
When the first monitoring means (126B) determines that the load is driven, it further comprises third monitoring means (326B) for monitoring the rate of change of the DC voltage,
The control means (124B) executes the output when the rate of change is less than or equal to a predetermined threshold, and waits for the output when the rate of change is greater than a predetermined threshold. Drive device.

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