Disclosure of Invention
The invention aims to provide a solution for remotely controlling the hot water temperature of a gas water heater, namely a device capable of remotely adjusting the temperature of the gas water heater.
in order to achieve the purpose, the invention provides a remote regulating device for the hot water temperature of a gas water heater, which comprises a first flow measuring unit, a second flow measuring unit, an adder circuit unit, a proportional value calculating unit, a flow threshold value switching unit and a proportional valve driving unit.
The gas water heater is provided with a cold water inlet, a first hot water outlet and a second hot water outlet; a first flow sensor is arranged in front of the first hot water outlet and used for detecting the outlet hot water flow of the first hot water outlet; and a second flow sensor is arranged in front of the second hot water outlet and used for detecting the outlet hot water flow of the second hot water outlet. Cold water flowing into the cold water inlet is heated and then flows out of the first hot water outlet and the second hot water outlet; the total inlet cold water flow of the cold water inlet is equal to the sum of the outlet hot water flows of the first hot water outlet and the second hot water outlet.
The first flow measuring unit converts the outlet hot water flow of the first hot water outlet detected by the first flow sensor into first flow voltage for output; and the second flow measuring unit converts the outlet hot water flow of the second hot water outlet detected by the second flow sensor into second flow voltage for output.
The adder circuit unit obtains the sum of the first flow rate voltage and the second flow rate voltage, and outputs a total flow rate voltage.
The proportional value calculating unit calculates and outputs a proportional value control voltage according to a ratio between the first flow rate voltage and the total flow rate voltage.
The flow threshold switch unit consists of a flow threshold setting circuit, a comparison driving circuit and a relay gas switch; the flow threshold setting circuit outputs a flow threshold voltage; the flow threshold switching unit functions to: when the total flow voltage is greater than the flow threshold voltage, the total flow of cold water at the inlet is greater than the flow threshold, and the relay gas switch is closed; when the total flow voltage is smaller than the flow threshold voltage, the total flow of the inlet cold water is smaller than the flow threshold, and the relay gas switch is disconnected.
The proportional valve driving unit consists of a fuel gas proportional regulating valve and a proportional valve driving circuit; the proportional valve drive circuit functions as: when the proportional value control voltage is increased, the proportional valve driving circuit controls the opening of the fuel gas proportional regulating valve to be increased; when the proportional value control voltage is reduced, the proportional valve driving circuit controls the opening degree of the fuel gas proportional regulating valve to be reduced.
The first flow voltage and the outlet hot water flow of the first hot water outlet are in a direct proportion relation; and the second flow voltage and the outlet hot water flow of the second hot water outlet are in a direct proportion relation.
And the proportional value between the second flow voltage and the outlet hot water flow of the second hot water outlet is equal to the proportional value between the first flow voltage and the outlet hot water flow of the first hot water outlet.
The flow threshold is determined by a flow threshold voltage; the flow threshold voltage and the flow threshold are in a direct proportional relation; the proportional value between the flow threshold voltage and the flow threshold is equal to the proportional value between the first flow voltage and the outlet hot water flow of the first hot water outlet.
The proportional value calculating unit calculates and outputs proportional value control voltage according to the ratio between the first flow rate voltage and the total flow rate voltage, and the proportional value control voltage and the ratio are in a direct proportional relation.
The hot water flow of the first hot water outlet and the second hot water outlet is adjusted and changed by the water mixing valve; 2 water inlets of the water mixing valve are respectively connected to a first hot water outlet and a second hot water outlet of the gas water heater through water pipes. Or the hot water flow of the outlets of the first hot water outlet and the second hot water outlet is respectively adjusted and changed by a first adjusting valve and a second adjusting valve; the water inlet of the first regulating valve is connected to a first hot water outlet of the gas water heater through a water pipe, and the water inlet of the second regulating valve is connected to a second hot water outlet of the gas water heater through a water pipe; the water outlets of the first regulating valve and the second regulating valve are communicated to form a water outlet end.
the control system of the gas water heater consists of the device, a controller, an ignition discharge needle, a flame induction needle, an exhaust fan and an electromagnetic valve; a gas proportion regulating valve in the device is arranged behind an electromagnetic valve in a gas pipeline. Or the control system of the gas water heater consists of a temperature adjusting controller, an ignition discharge needle, a flame induction needle, an exhaust fan, an electromagnetic valve, a gas proportion adjusting valve, a first flow sensor and a second flow sensor; the control circuit in the device is included in the tempering controller; the control circuit in the device comprises corresponding circuits in a first flow measurement unit, a second flow measurement unit, an adder circuit unit, a proportional value calculation unit, a flow threshold value switch unit and a proportional valve driving unit.
The electromagnetic valve preferably uses a safety stop valve in a fuel gas proportional valve assembly; the gas proportion regulating valve is a gas proportion regulating valve in a gas proportion valve assembly.
The invention has the advantages that a wired or wireless remote controller is not needed, the gas flow is changed by adopting a method of controlling two paths of hot water flows through the water valve, so that the outlet hot water temperature of the water heater is changed, the remote adjustment of the hot water temperature of the gas water heater is realized, and the control result is stable and reliable.
Detailed Description
The present invention will be described in further detail with reference to examples and drawings, but the present invention is not limited thereto.
Fig. 1 shows a schematic block diagram of a remote hot water temperature control device for a gas water heater, which includes a first flow measurement unit 100, a second flow measurement unit 200, an adder circuit unit 300, a proportional value calculation unit 400, a flow threshold value switch unit 500, and a proportional valve driving unit 600.
The gas water heater is provided with 1 cold water inlet and 2 hot water outlets, and the 2 hot water outlets are respectively provided with a flow sensor for respectively detecting the hot water flow at the outlets of the 2 hot water outlets. The first flow measurement unit 100 is provided with a first flow voltage U1 output end, the second flow measurement unit 200 is provided with a second flow voltage U2 output end, and the first flow measurement unit 100 and the second flow measurement unit 200 respectively measure the hot water flow Q1 and Q2 at the outlet of 2 hot water outlets and respectively output the hot water flow with a first flow voltage U1 and a second flow voltage U2. U1 and U2 are sent to the adder circuit unit 300, and a total flow rate voltage U0 corresponding to the inlet cold water total flow rate Q0 is obtained; the total inlet cold water flow rate Q0 is equal to the sum of the outlet hot water flow rates Q1 and Q2 of the 2 hot water outlets. The total flow voltage U0 is sent to a flow threshold value switch unit 500 to be compared with a set flow threshold value voltage, and when the total inlet cold water flow Q0 is larger than the set flow threshold value, a relay gas switch is controlled to be closed; and when the total inlet cold water flow Q0 is smaller than a set flow threshold value, the gas switch of the control relay is switched off.
The first flow rate voltage U1 and the total flow rate voltage U0 are sent to the proportional value calculating unit 400, the proportional value calculating unit 400 calculates the ratio between the first flow rate voltage U1 and the total flow rate voltage U0, and the proportional value control voltage UK is obtained from the ratio; the proportional value control voltage UK is sent to the proportional valve driving unit 600, and the opening degree of the gas proportional control valve is controlled by the UK; when the UK is the minimum value, the opening degree of the gas proportion regulating valve is the minimum; and when the UK is the maximum value, the opening degree of the gas proportion regulating valve is maximum.
The structural block diagram of the installation embodiment 1 of the flow sensor is shown in fig. 2, and the water path system of the device is composed of a heat exchanger 901, a first flow sensor 902, a second flow sensor 903, a first hot water outlet 904, a second hot water outlet 905, a cold water inlet 906, a cold water pipe 921, a main hot water pipe 922, a first hot water pipe 923, a second hot water pipe 924, a mixing valve 931, a first connecting water pipe 925, a second connecting water pipe 926, a mixing hot water pipe 927 and a water outlet nozzle 932 outside the gas water heater.
The gas water heater is provided with 1 cold water inlet and 2 hot water outlets, and the cold water pipe 921 is connected between the cold water inlet 906 and the heat exchanger 901; one end of the first hot water pipe 923 is connected to the first hot water outlet 904, and the other end is communicated to the water outlet end of the main hot water pipe 922; one end of the second hot water pipe 924 is connected to the second hot water outlet 905, and the other end is connected to the water outlet end of the main hot water pipe 922; the water inlet end of the main hot water pipe 922 is connected to the heat exchanger 901.
The first flow sensor 902 is arranged in front of the first hot water outlet 904 and is used for detecting the outlet hot water flow Q1 of the first hot water outlet 904; the second flow sensor 903 is installed in front of the second hot water outlet 905 and is used for detecting the outlet hot water flow Q2 of the second hot water outlet 905. Specifically, the first flow sensor 902 is installed on the first hot water pipe 923, and the second flow sensor 903 is installed on the second hot water pipe 924.
2 water inlets of the water mixing valve 931 are connected to the first hot water outlet 904 and the second hot water outlet 905 of the gas water heater through a first connecting water pipe 925 and a second connecting water pipe 926 respectively; the outlet of the mixing valve 931 is connected to the outlet nozzle 932 by a mixing hot water pipe 927. When the mixing valve 931 is a cold water and hot water mixing valve, the first connecting water pipe 925 is connected to a hot water inlet of the mixing valve 931, and the second connecting water pipe 926 is connected to a cold water inlet of the mixing valve 931. The outlet hot water flow rates Q1, Q2 of the first hot water outlet 904 and the second hot water outlet 905 are changed by adjusting the mixing valve 931.
Fig. 3 shows a block diagram of a flow sensor mounting embodiment 2, which is different from embodiment 1 in that a first adjusting valve 933 and a second adjusting valve 934 are used instead of a mixing valve 931; the water inlet of the first adjusting valve 933 is connected to the first hot water outlet 904 of the gas water heater through a first connecting water pipe 925, and the water inlet of the second adjusting valve 934 is connected to the second hot water outlet 905 of the gas water heater through a second connecting water pipe 926. The water outlets of the first adjusting valve 933 and the second adjusting valve 934 are communicated to form a water outlet end which is connected with the mixed hot water pipe 927. The outlet hot water flow rates Q1 and Q2 of the first hot water outlet 904 and the second hot water outlet 905 are changed by adjusting a first adjusting valve 933 and a second adjusting valve 934, respectively.
An embodiment of the first flow measurement unit 100 is shown in fig. 4. The first flow sensor 902 is a low cost hall water flow sensor with the sensor output being a pulse frequency proportional to flow. The first flow rate measuring unit 100 is composed of a first flow rate sensor 902 and a frequency-voltage conversion circuit. In the embodiment shown in fig. 4, the frequency-voltage conversion circuit is composed of a monolithic frequency-voltage converter 101 and its peripheral components, namely a resistor 102, a resistor 104, a resistor 106, a capacitor 103 and a capacitor 105, the monolithic frequency-voltage converter 101 is of the type LM2917, and the first flow voltage U1 is output from the LM 2917. The frequency-voltage conversion circuit may also adopt other circuits capable of realizing the frequency/voltage conversion function.
The second flow rate measuring unit 200 is composed of a second flow rate sensor 903 and a frequency-voltage conversion circuit, the second flow rate sensor 903 is a low-cost hall water flow rate sensor, the principle and structure of the frequency-voltage conversion circuit are completely the same as those of the frequency-voltage conversion circuit in the first flow rate measuring unit 100, and the output is a second flow rate voltage U2.
The first and second flow measurement units 100, 200 may also employ other measurement schemes, such as measuring Q1, Q2 using integrated flow transmitters that directly output U1, U2, respectively.
The first flow measurement unit 100 detects Q1 and outputs U1, U1 and Q1 in a direct proportional relationship
U1=KQ·Q1;
The second flow measurement unit 200 detects Q2 and outputs U2, U2 and Q2 in a direct proportional relationship
U2=KQ·Q2;
KQ in the above 2 expressions is a flow measurement coefficient. The first flow measurement unit 100 and the second flow measurement unit 200 have the same flow measurement coefficient.
The adder circuit unit 300 receives the first flow rate voltage U1 and the second flow rate voltage U2, and outputs a total flow rate voltage U0, where U0 is the sum of U1 and U2. The adder circuit unit 300 may employ any voltage adder circuit, one embodiment of which is shown in fig. 5. The adder circuit unit 300 shown in fig. 5 is a non-inverting adder composed of an operational amplifier 301, a resistor 302, a resistor 303, a resistor 304, and a resistor 305. Since the flow measurement coefficients of the first flow measurement unit 100 and the second flow measurement unit 200 are the same, the ratio between the total flow voltage U0 and the total outlet hot water flow Q0 of the 2 hot water outlets is also the same, i.e., the flow measurement coefficients are the same. The total outlet hot water flow Q0 of the 2 hot water outlets is the total inlet cold water flow Q0.
The proportional value calculating unit 400 receives the first flow rate voltage U1 and the total flow rate voltage U0 as inputs, and outputs the proportional value control voltage UK, and an embodiment thereof is shown in fig. 6 and includes a parallel a/D converter 401, a parallel D/a converter 402, a 555 time base device 411, a resistor 412, a resistor 413, and a capacitor 414.
the model of the parallel a/D converter 401 is an 8-bit parallel a/D converter ADC 0841. The 555 time base device 411, the resistor 412, the resistor 413 and the capacitor 414 form an oscillator, periodic pulses output by the oscillator are connected to a start conversion input end WR of the parallel A/D converter 401, and each pulse starts an A/D conversion, so that the parallel A/D converter 401 works in an automatic continuous conversion mode.
The analog voltage input negative terminal VIN-, the output enable terminal RD, the chip select terminal CS, the digital ground DGND and the analog ground AGND of the ADC0841 are connected to a common ground, and the power supply terminal VCC of the ADC0841 is connected to the positive power supply + VDD. When the output enable terminal RD of the ADC0841 is inputted with a low level, the data output terminals DB7 DB0 keep outputting valid. When each conversion of the ADC0841 is finished, the result is automatically output from the data output terminals DB7 DB 0.
U1 is connected to the analog voltage input VIN + of ADC0841 and U0 is connected to the reference voltage input VREF of ADC 0841. Let X be the 8-bit digital signal output from the output terminals DB 7-DB 0 of the ADC0841, and the maximum value thereof is 255. Then there is
I.e. the ratio between the two input voltages U1, U0 is
The model of the parallel D/a converter 402 is an 8-bit parallel D/a converter AD 5330. The parallel data input end of the AD5330 is DB 7-DB 0, the reference voltage input end is VREF, and the conversion voltage output end is VOUT.
a buffer switch control end BUF, an output proportion control end GAIN, an input register control end WR, a DAC register control end LDAC, a chip selection end CS and a ground end GND of the AD5330 are connected to a common ground, and a zero clearing end CLR, a low power consumption control end PD and a power supply end VDD of the AD5330 are connected to a positive power supply + VDD. When the input register control end WR of the AD5330 and the DAC register control end LDAC input are in a direct D/A conversion state, and when the conversion delay is not considered, the conversion voltage output end VOUT reflects the data conversion results of the parallel data input ends DB 7-DB 0 in real time.
parallel data inputs DB 7-DB 0 of the AD5330 are connected to parallel data outputs DB 7-DB 0 of the ADC0841, and the input data is X, and the maximum value is 255. Let the voltage input to the reference voltage input terminal VREF of AD5330 be UM, and the voltage output from the conversion voltage output terminal VOUT be UK, then there is
Considering the input-output relationship of AD0841, the proportional value calculating unit 400 follows the equation
According to the ratio of the first flow voltage U1 to the total flow voltage U0, the proportional value control voltage UK is calculated. UM is the maximum value of the proportional-value control voltage UK, in the embodiment shown in fig. 6 UM is connected to the positive supply + VDD. UM may also use other voltage values to control the maximum value of the proportional-value-control voltage UK.
The embodiment shown in fig. 6 is suitable for the situation that the requirement on the calculation speed of the comparative value is not high and the change of the input voltage is relatively gentle. In the invention, U1 and U0 reflect the flow of the water heater, and the change is smooth, so the invention is suitable. The proportional value calculating unit 400 may also adopt other analog dividers and analog multiplier circuits, for example, an analog divider and an analog multiplier circuit which are composed of integrated analog multipliers/dividers such as AD734 and AD 534.
The flow rate threshold value switching unit 500 receives the total flow rate voltage U0 as an input, and outputs a switching signal related to the flow rate threshold value QY. Fig. 7 shows an embodiment of the flow threshold value switching unit 500, which is composed of a comparator 501, a resistor 502, a resistor 503, a resistor 504, a transistor 505, a freewheeling diode 506, a relay coil 507, and a relay gas switch 508, and a switching signal related to the flow threshold value QY is the closing and opening of the relay gas switch 508.
A voltage division circuit consisting of the resistor 502 and the resistor 503 is a flow threshold value QY setting circuit and is used for setting a flow threshold value voltage UY; the set flow rate threshold QY can be changed by changing the voltage division ratio between the resistor 502 and the resistor 503. The relationship between the flow threshold voltage UY and the flow threshold value QY is
The comparator 501, the resistor 504, the triode 505, the freewheeling diode 506 and the relay coil 507 constitute a comparison driving circuit of the relay gas switch 508.
When the inlet cold water total flow Q0 is greater than the flow threshold value QY, the total flow voltage U0 is greater than the flow threshold voltage UY, the comparator 501 outputs high level, the triode 505 is conducted, the relay coil 507 is electrified, and the relay gas switch 508 is closed; when the total inlet cold water flow Q0 is less than the flow threshold QY, the relay gas switch 508 is turned off.
The proportional valve driving unit 600 is composed of a gas proportional regulating valve and a proportional valve driving circuit, and the embodiment of the proportional valve driving circuit is shown in fig. 8 and is composed of a power operational amplifier 601, a resistor 602, a resistor 603 and a freewheeling diode 604. A freewheeling diode 604 is connected in parallel across the proportional coil 630. The working principle is as follows: the flow of the gas can be changed by changing the opening of the gas proportion adjusting valve, so that the combustion power of the gas water heater is changed, and the temperature of hot water is changed. The method specifically comprises the following steps: when the proportional value control voltage UK is increased, the output voltage UB of the proportional valve driving circuit is increased, the current on the proportional coil 630 is increased, the opening degree of the gas proportional regulating valve is increased, the combustion power of the gas water heater is increased, and the temperature of hot water is increased; when the proportional value control voltage UK is reduced, the output voltage UB of the proportional valve driving circuit is reduced, the current on the proportional coil 630 is reduced, the opening degree of the gas proportional regulating valve is reduced, the combustion power of the gas water heater is reduced, and the temperature of hot water is reduced.
The resistor 602 and the resistor 603 are used for adjusting the range of the output voltage UB of the proportional valve driving circuit, and when the proportional value control voltage UK is equal to the maximum control voltage UM, the maximum control current, i.e., the rated current, flows through the proportional coil 630, so that the opening degree of the gas proportional regulating valve reaches the maximum value.
Other types of drive circuits may be used for the proportional valve drive circuit, such as triode power drive circuits, voltage/PWM conversion and PWM drive circuits, and so forth. The proportional valve drive circuit functions as: when the proportional value control voltage UK increases, the current on the proportional coil 630 is controlled to increase; when the proportional value control voltage UK decreases, the current on the proportional coil 630 is controlled to decrease; when the proportional value control voltage UK is the maximum value UM, the current on the proportional coil 630 is controlled to be the rated current.
The block diagram of the conventional control system of the gas water heater is shown in fig. 9, and the conventional control system comprises a controller 10, a water control switch 11, an ignition discharge needle 12, a flame induction needle 13, an exhaust fan 14 and an electromagnetic valve 15. The working principle is as follows: after a water outlet faucet of the water heater is turned on, the water control switch 11 is turned on, the controller 10 controls the exhaust fan 14 to work by electrifying, and simultaneously controls the ignition discharge needle 12 to ignite by discharging; slightly delaying to control the electromagnetic valve 15 to suck and open the coal gas; the ignition discharge needle 12 keeps igniting for tens of seconds, so that the ignition reliability is ensured; after the discharge is finished, the flame induction needle 13 is used for determining whether the ignition is successful or not, and the controller 10 controls the maintaining electromagnetic valve 15 to suck and open the coal gas when the ignition is successful through the induction of the flame induction needle 13; when the ignition is not successful, the electromagnetic valve 15 is controlled to bounce, the gas is cut off, and the water heater stops heating.
In order to ensure the safe use of the gas water heater, the gas water heater can also comprise a wind pressure switch 16 and a temperature control switch 17 shown in fig. 9. In the use process of the water heater, if the air pressure switch 16 detects that the exhaust fan is not started, or the temperature control switch 17 detects that the fire is too large and the temperature of the outlet water is too high, or the water control switch 11 detects that the water flow is too small, the electromagnetic valve 15 can be bounced to turn off the gas, and safety accidents are avoided.
When the device of the invention is used in a gas water heater, the control system of the gas water heater consists of the device and the controller 10, the ignition discharge needle 12, the flame induction needle 13, the exhaust fan 14 and the electromagnetic valve 15 of the system shown in figure 9, or can also selectively comprise a wind pressure switch 16 and a temperature control switch 17. The water control switch 11 in the conventional control system of the gas water heater shown in fig. 9 is replaced by a relay gas switch 508 in the device of the present invention, in which a gas proportional regulating valve is installed in the gas pipeline after the electromagnetic valve 15. Since a gas proportional regulating valve and a safety stop valve are usually included in a conventional gas proportional valve assembly, the electromagnetic valve 15 in the conventional control system of the gas water heater shown in fig. 9 preferably uses the safety stop valve in the gas proportional valve assembly, and the gas proportional regulating valve uses the gas proportional regulating valve in the gas proportional valve assembly.
when the device is used for the gas water heater, the controller 10 can use various popular ignition controllers of the gas water heater at present, such as a DKG2 controller, a DKG3 controller, a DHS-B7A controller, a DHS-B7B controller, a HD 7PQA1-CP controller and various other ignition controllers of the gas water heater.
When the device is used for the gas water heater, a control circuit in the device can be combined with the controller 10 to form a new temperature regulation controller. Fig. 10 shows a block diagram of a gas water heater control system with a temperature remote adjusting function, which is composed of a temperature adjusting controller 20, an ignition discharge needle 12, a flame sensing needle 13, an exhaust fan 14, an electromagnetic valve 15, a gas proportional adjusting valve 21, a first flow sensor 902, and a second flow sensor 903, or may further include a wind pressure switch 16 and a temperature control switch 17. The temperature controller 20 is composed of a functional circuit in the controller 10 and a control circuit in the apparatus of the present invention, and the control circuit in the apparatus of the present invention includes corresponding circuits in the first flow measuring unit 100, the second flow measuring unit 200, the adder circuit unit 300, the proportional value calculating unit 400, the flow threshold value switching unit 500, and the proportional valve driving unit 600. Similarly, the solenoid valve 15 in fig. 10 preferably uses a safety shut-off valve in a gas proportional valve assembly, and the gas proportional control valve 21 uses a gas proportional control valve in the gas proportional valve assembly.
The above description is only an example of the present invention and is not intended to limit the present invention, and various modifications and changes may be made to the present invention by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.