JPH01203783A - Proportional valve controller - Google Patents

Abstract

PURPOSE:To obtain a controller for a proportional valve which is provided with a variety of characteristics by installing a digital calculator for controlling the proportional control valve on the basis of the conduction electric current memorized in a ROM. CONSTITUTION:A ROM 42a is connected with each data bus of a digital calculator 42, and the necessary data is successively read by the control by the calculator 42. The digital calculator 42 reads out the data according to the inputted number of revolution of a fan 12 for combustion and sets the obtained value as control output supplied into a proportional valve 2. Since the data as conduction electric current value memorized in the ROM 42a can be freely set according to the number of revolution of the fan 12 for combustion, fine characteristic for each kind of gas can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a control device for a proportional control valve that controls the amount of fuel supplied to a burner in accordance with the energizing current.

[Prior art] Combustion devices such as water heaters and air conditioners have different calorific values depending on the fuel used. Especially when gas is used as fuel, it is necessary to change the amount of fuel supplied to the burner in order to obtain the same calorific value. Since the flow rate varies greatly depending on the gas type, the proportional control valve that controls the supply amount must perform control according to each gas type. To do this, it is necessary to control the proportional control valve for each gas type using the same circuit. A device equipped with a switching means to change the control characteristics (Japanese Patent Publication No. 57-3844) and a device that switches the resistance value of the energizing circuit of a proportional control valve (Japanese Patent Publication No. 60-29852) have been introduced. There is.

[Problem H to be solved by the invention] However, in each of the above inventions, the current value by the energizing circuit to the proportional control valve is directly changed, so the characteristics obtained by switching are similar to those obtained by changing the gas type in the same model. However, there is a problem in that it is difficult to obtain the optimum characteristics by switching because it is difficult to obtain characteristics sufficiently suited to each gas type.

The present invention provides a proportional valve control device that is capable of obtaining the optimum energizing current characteristics according to each fuel, and also that can easily obtain the energizing current characteristics suitable for different fuels and different models. The purpose is to

[Means for Solving the Problems] The present invention provides a proportional control valve that is provided in a fuel supply path that supplies fuel to a burner and controls the amount of fuel supplied to the burner in accordance with an energizing current; A proportional valve control device comprising a control means for controlling the current flowing through the proportional control valve according to the combustion amount, wherein the control means stores a value of the current flowing through the proportional control valve according to the required combustion amount. The technical means includes a ROM and a counting type computer that controls the proportional control valve based on the energizing current value stored in the ROM.

[Function] In the present invention, the current value to be applied to the proportional control valve is set in the ROM according to the required combustion amount of the burner and according to the fuel used.
When controlling the proportional control valve according to the required combustion amount, the counting type computer performs control based on the energizing current value stored in the ROM.

[Effects of the Invention] In the present invention, the proportional control valve is energized based on the energizing current value stored in the ROM. Therefore, since it is possible to easily set an arbitrary current value in accordance with the required combustion amount of the burner, it is possible to easily configure a proportional valve control device with characteristics corresponding to different fuels. Can be done.

In addition, even when controlling a proportional control valve for a different model, it can be controlled as is by setting the energizing current value according to the required combustion amount, so we designed a proportional valve control device with the same basic configuration. and RO according to each model
Proportional valve control devices with various characteristics can be obtained by simply changing M.

[Example] Next, a description will be given based on an example of a gas water heater equipped with a proportional valve control device of the present invention.

The gas water heater of this embodiment, which is schematically shown in FIG. 2, has a combustor 1
0, a fuel pipe 20, a wood pipe 30, and a control device 40.

The combustor 10 includes a burner group 11 provided in the water heater case 1 and a combustion fan 12 that supplies combustion air. All-in-one combustion is performed using only air, and the combustion gas is discharged from the exhaust port 2.

The burner group 11 is a two-bar burner with a plurality of beam burners arranged in two rows, and above near the bar group 11 there is a sparker 14 of an ignition device, a flame rod 15 for flame detection, and a flame rod 15 for flame detection. A thermocouple 16 is provided respectively.

The fuel pipe 20 is a gas pipe that supplies fuel gas to the nozzle 13, and includes, in order from the upstream side, a main solenoid valve 21, a main solenoid valve 22, and a proportional valve 23 that adjusts the amount of fuel supplied to the burner group 11. At the downstream of the proportional valve 23, the fuel pipe 20 is branched to supply fuel gas to each of the multiple sets of two-bar burners. In order to burn only one series,
A switching valve 24 is provided.

The water pipe 30 includes a supply pipe 31 and a hot water supply pipe 31a connected to a water supply source and a hot water supply port (not shown), respectively, and a heat exchanger 32 and a bypass pipe 3 provided to communicate these.
2a, a part of the water supplied from the supply pipe 31 is led to the hot water supply pipe 31a via the heat exchanger 32, and the remaining part is led to the hot water supply pipe 31a via the bypass pipe 32a. A bypass valve 33 is provided at the downstream confluence section, and mixes the water heated by the heat exchanger 32 and the water directly guided through the bypass pipe 32a by appropriately adjusting the ratio thereof.

On the other hand, a water flow control valve 34, a water flow sensor 35, and an inlet water temperature thermistor 36 are installed in the supply pipe 31 from the upstream side, and a heat exchange thermistor 37 is installed downstream of the heat exchanger 32.
A is provided with an outlet hot water temperature thermistor 38, and the hot water supply pipe 31a is provided with an antifreeze protector (not shown).

The bypass valve 33 and the water flow control valve 34 are each driven by a geared motor, and the water flow sensor 35 has a number of impellers (not shown) rotated by the water flow passing through the supply pipe 31. Output pulse.

As shown in FIG. 1, the control device 40 includes each circuit serving as an interface 41 for exchanging signals with each of the above-mentioned parts provided in the gas water heater, and a microcomputer 42 serving as the center of the control device 11f40. It consists of a safety circuit 43 for ensuring safety, a solenoid valve energizing relay circuit 44, and a power supply unit 45 that supplies power to all of these, and a controller 46 for operating the gas water heater.
and a mode setting circuit 47 for presetting the operating mode of the microcomputer 42.

First, each circuit as the interface 41 will be explained.

The sparker circuit 51 includes a high voltage generation section that generates a high voltage for causing spark discharge to the sparker 14, and a discharge detection section that detects the spark discharge at the sparker 14.

The flame temperature detection circuit 52 is a circuit that amplifies the output voltage of the thermocouple 16 according to the temperature of the flame to be detected for use as a control signal, and the amplified signal is used to control the air-fuel ratio during combustion. .

The water temperature detection circuit 53 is a circuit for obtaining temperature signals from the resistance values of each thermistor arranged in the water pipe 30.
The temperature signal is obtained by dividing the power supply voltage by resistors connected in series with each thermistor.

The geared motor drive circuit 54 is a geared motor energization circuit for driving the water flow control valve 34 and the bypass valve 33, respectively, and each geared motor is energized based on the resistance value of a potentiometer (not shown) provided for detecting the opening degree of the response valve. controlled by

The fan circuit 55 is a circuit for driving the combustion fan 12 based on the pulse signal transmitted from the microcomputer 42, and changes the output voltage according to the pulse width of the transmitted pulse signal to the control voltage of the fan drive circuit. Apply as. Further, a rotation speed detection circuit for sending a rotation speed signal of the combustion fan 12 to the microcomputer 42 is provided.

The proportional valve port path 56 is a circuit that energizes the proportional valve 23 that adjusts the fuel gas.

The flame detection circuit 58 is a circuit for detecting flame by the flame rod 15 and obtaining a flame detection signal, and the flame detection signal is sent to the microcomputer 42 and the safety circuit 43, respectively.

The water flow circuit 59 operates based on a pulse signal from the water flow sensor 35 that is generated according to the amount of water passing through the water pipe 30.
A pulse signal is transmitted to the microcomputer 42, and when the amount of water passing through the water pipe 30 exceeds a certain amount, a switching signal is sent to the relay circuit power supply 45b of the power supply section 45, and a water flow signal is transmitted to the safety circuit 43. Transmit.

The microcomputer 42 is designed so that it can be used not only for the gas water heater of this embodiment but also for other water heaters with different hot water supply amounts and sizes, and stores programs and part of each data necessary for its operation. A custom LSI with a built-in storage device performs predetermined sequence control, combustion amount control, and water amount control.

For combustion amount control and fishery control, inlet water temperature thermistor 36
, feedforward control that controls the combustion amount and water amount in advance using signals from the heat exchange thermistor 37, controller 46, and water flow sensor 35, and further corrects the combustion amount and water amount using the outlet hot water temperature thermistor 38 when predetermined conditions are met. Feedback control is performed.

In the combustion amount control, the combustion fan 12 is controlled based on the combustion amount determined from each thermistor, etc., and the current flowing through the proportional valve 23 is further controlled in accordance with its rotation speed. However, even if the same calorific value is obtained, the flow rate will vary greatly depending on the type of fuel gas used. Therefore, the value of current flowing through the proportional valve 23 is simply determined in accordance with the rotation speed of the combustion fan 12. Therefore, in this embodiment, in order to create a design that can be used with other gas types, the current value to the proportional valve 23 is set in advance to correspond to the rotation speed of the combustion fan 12 for each gas type used. For example, the current value is stored in the ROM 42a with the characteristics shown by the solid line A in FIG. 3.

The ROM 42a is connected to each data bus of the microcomputer 42, and necessary data is sequentially read out under control from the microcomputer 42.
The microcomputer 42 receives input from the combustion fan 1.
2 and is read out in correspondence with the rotation speed of 2, and is used as a control output to the proportional valve 23. Here, the data as the current value stored in the ROM 42a can be freely set in accordance with the rotation speed of the combustion fan 12, so that detailed characteristics can be given to each gas type.

As a result, the control device 40 of this embodiment only needs to include the ROM 42a having data corresponding to the type of gas used.
It can be used with water heaters of different gas types, and as shown in solid lines B and C in Figure 3, the current range can be set freely, giving detailed characteristics suitable for each gas type. be able to.

Note that this ROM 42a is inserted and fixed in a ROM socket provided on a board (not shown) in the control device 40 at the time of factory shipment depending on the type of gas required, and normally there is no need to change it afterward once it is fixed. .

The solenoid valve energizing relay circuit 44 is a circuit consisting of a relay for respectively energizing the original solenoid valve 21, the main solenoid valve 22, and the switching valve 24 in accordance with a control signal from the microcomputer 42.

When a plug (not shown) is inserted into an outlet, the power supply unit 45 converts the electric power for operating the above-mentioned circuits of the control device 40 into the voltage necessary for each circuit and constantly supplies the voltage. Now, microcomputer 42
a microcomputer power supply 45a that supplies power to the microcomputer, and a relay circuit power supply 45 that supplies power to the solenoid valve energizing relay circuit 44.
b has a switching function that stops the power supply in response to the energization stop signal from the safety circuit 43, which stops the operation of the microcomputer 42 and stops the energization to each electromagnetic valve, thereby stopping the fuel supply.

In addition, the relay circuit power supply 45b that supplies power to the solenoid valve energizing relay circuit 44 can energize each solenoid valve only when a switching signal from the water flow circuit 59 is transmitted, and the water flow is detected. If not, fuel gas is not supplied to the burner group 11, so there is no need to worry about dry firing.

In addition, the power supply section 45 is provided with a temperature fuse and an overload switch (not shown) in the electric line connected to the commercial power source to further ensure safety.

The controller 46 is for setting and operating the operating state of the gas water heater, and includes a small-capacity microcomputer operated by power from a communication circuit 57 and a communication circuit in order to exchange signals with the microcomputer 42. , modulates the setting signal and sends it to the microcomputer 42. The controller 46 also has a display function, which displays the set hot water temperature using digital numbers on a liquid crystal display, and also indicates when the combustor 10 is burning by a lamp.

The mode setting circuit 47 is a circuit for presetting the operating mode of the microcomputer 42 according to the presence or absence of a remote control, hot water supply capacity, exhaust equipment, etc. at the time of shipment from the factory or when installing the gas water heater. It is set by a dip switch connected to each terminal of a custom IC forming the microcomputer 42.

The gas water heater of this embodiment having the above configuration operates as follows.

When the user turns on an operation switch (not shown) of the controller 46 and sets the hot water temperature, the combustion fan 12 starts rotating. Furthermore, when a water faucet (not shown) is operated, water flows into the water pipe 30, and the water supplied by the supply pipe 31 passes through the water flow control valve 34 and the water flow sensor 35, and then passes through the heat exchanger 32 and the bypass pipe. 32a, the respective outflow amounts are adjusted by the bypass valve 33, and the hot water supply pipe 31a
The hot water flows out from the hot water supply port (not shown) through the hot water supply port.

A water flow signal and a pulse signal corresponding to the water flow transmitted from the water flow sensor 35 via the water flow circuit 59 are transmitted to the electromagnetic valve energizing relay circuit 44 and the microcomputer 42.

Then, in the solenoid valve energizing relay circuit 44, each solenoid valve becomes energized according to the control signal from the microcomputer 42, and on the other hand, the microcomputer 42 detects a predetermined number or more of pulse signals transmitted from the water flow circuit 59. Then, as the ignition operation of the combustor 10, the sparker circuit 51
The high voltage generator is energized to cause spark discharge to the sparker 14.

When the spark discharge in the sparker 14 is detected by the operation detection section of the sparker circuit 51, the microcomputer 42 changes the control signal for the original solenoid valve 21 and the main solenoid valve 22, which had been the signal to close the valve, to Change the signal to open and send it.

Therefore, the original solenoid valve 21 and the main solenoid valve 22 are energized by the solenoid valve energizing relay circuit 44, and the fuel gas is supplied to the nozzle 13.
The fuel is ejected from the air, mixed with combustion air, and supplied to the burner group 11, where it is ignited by the sparker 14, which is already in operation.

When ignition is detected by the flame rod 15 and a flame detection signal is sent from the flame detection circuit 58, the inlet water temperature thermistor 36, the heat exchange thermistor 37, and the outlet water temperature thermistor 38
The required combustion amount is calculated based on the detection signals from each thermistor and water flow sensor 35, and the setting signal from the controller 46, and based on the calculation results, the combustion fan 12, proportional valve 23, switching valve 24, bypass Valve 33 and water flow control valve 34 are controlled. Also, after ignition,
Correction control of the air-fuel ratio is also performed based on the signal from the thermocouple 16, but this control is not performed for a certain period of time until the temperature of the thermocouple 16 stabilizes.

After that, if there is a change in the amount of hot water or the set temperature, water amount control or combustion amount control is performed in accordance with the change.

In the water flow control, the ratio of the flow rate passing through the heat exchanger 32 and the bypass pipe 32a by the bypass valve 33 is changed. In addition, when changing the combustion amount, the combustion fan 12 is controlled according to the calculated combustion amount, and the ROM
Proportional valve 2 based on the energizing current value read from 42a.
3 is energized.

As described above, according to the proportional valve control device of the present invention, the amount of fuel supplied according to the determined combustion amount is read out from the ROM in which the energizing current value is stored in advance in accordance with the combustion amount. Therefore, the characteristics of the proportional valve can be set freely and precisely. Therefore, since different characteristics can be easily set, it can also be used in combustion devices using different types of fuel.

In this embodiment, a gas water heater is shown as an example, but it can also be used for a space heater or a combustion device that uses liquid fuel.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a block diagram showing a control device for a gas water heater according to the present embodiment, Fig. 2 is a schematic configuration diagram of a gas water heater according to an embodiment of the present invention, and Fig. 3 is a proportional FIG. 3 is a characteristic diagram showing an example of current value characteristics of a valve. In the figure, 40...control device (proportional valve control device), 4.
・Microcomputer (counting type calculation 81), 42
a...ROM.

Claims (1)

[Claims] 1) A proportional control valve that is provided in a fuel supply path that supplies fuel to the burner and controls the amount of fuel supplied to the burner in accordance with the energization current, and energization of the proportional control valve in accordance with the required combustion amount of the burner. In a proportional valve control device comprising a control means for controlling current, the control means includes a ROM that stores a current value to be applied to the proportional control valve according to the required combustion amount.
and a counting type computer that controls the proportional control valve based on the energizing current value stored in the ROM.