JPH0268449A - Bypass mixing type hot water feeder - Google Patents

Abstract

PURPOSE:To provide a stable temperature of fed-out hot water by a method wherein a control device is provided for determining a degree of opening of a metering valve allowing for an amount of correction at the time of a previous feeding-out of the hot water stored in a memory means when a hot water feeding-out operation is started. CONSTITUTION:As a feeding-out of hot water is started, a degree of opening of a metering valve 4 required for getting a set temperature in response to an amount of fed water, a set temperature and a feeding water temperature and the like by means 5 for controlling the metering valve. A degree of opening defined by this means 5 for controlling the metering valve is determined with reference to a degree of opening corrected by a degree of opening correcting means 6 of the previous hot water feeding-out time stored in a circuit memory means 7. With this arrangement, an error between the hot water feeding-out temperature and the set temperature caused by a disturbance of equipment and the like is corrected just after a starting of the feeding-out of the hot water.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a bypass mixing type water heater that supplies hot water by mixing hot water that has passed through a heat exchanger and water that has bypassed the heat exchanger. 1-ru.

[Prior Art] In water heaters, if the temperature of the heat exchanger that exchanges heat obtained by combustion of fuel with water is low, water generated by combustion of fuel will leak into the heat exchanger. I end up wearing it.

Therefore, we installed a bypass waterway to bypass the heat exchanger.
Bypass mixing mixes hot water that has passed through a heat exchanger and water that has passed through a bypass waterway downstream of the heat exchanger, keeping the temperature of the heat exchanger high and lowering the temperature of the hot water obtained from the water heater. type water heaters are known.

Conventional bypass mixing type water heaters have a governor valve installed upstream of the heat exchanger on the side of the heat exchanger from the branching point between the heat exchanger and the bypass waterway to keep the amount of water flowing into the heat exchanger constant. The amount of combustion and
Ij installed in the bypass waterway.

The desired amount of hot water was obtained by controlling the opening of the throttle valve and the feed pump.

[Problems to be Solved by the Invention] However, in the conventional bypass mixing type water heater, when the water pressure flowing into the water heater changes, the amount of water flowing through the bypass channel changes. For this reason, the temperature of hot water after mixing fluctuates due to fluctuations in water pressure.

Then, the conventional control device, after the temperature of the hot water fluctuates,
The combustion amount and the opening degree of the bypass waterway throttle valve were controlled in accordance with the fluctuations. However, in conventional bypass mixing type water heaters, the outlet temperature is controlled so that it reaches the L+ temperature after the outlet temperature changes. 9 Therefore, the present applicant has devised a technology to solve the problem described in 1.This invention has been developed to solve the problem described in 1. , a restriction is provided to regulate the total amount of water that passes through the heat exchanger and the bypass waterway.This technology maintains a constant ratio of water that passes through the heat exchanger and the bypass waterway.

This means that even if the water pressure supplied to the water heater changes, the heat exchange #
Since the amount of hot water that passes through the IA device and is heated and the amount of water that passes through the bypass waterway is always in a constant ratio, the hot water temperature after mixing is stable.

By adding the following technology, this technology
The hot water temperature can be set as a set temperature.

The technology involves installing a throttle valve in the water heater's bypass waterway that can adjust the amount of water that passes through the bypass waterway. and,
The opening degree of the throttle valve is determined by the throttle valve control means based on the amount of water entering, the set temperature, the water entering temperature, etc. And furthermore,
If an error occurs between the tapped water temperature after mixing and the set temperature due to the opening correction means, the opening determined by the throttle valve control means is corrected to eliminate this error.

However, correcting the opening degree of the throttle valve by feedback means that the opening degree of the throttle valve is determined by the throttle valve control means (feed forward) every time hot water is discharged.
Opening degree YiM - It is prohibited to shift to the opening degree corrected by the means (feedback). This means that each time hot water is tapped, the tapped water temperature changes from a different temperature to the set temperature.

The present invention has been made in view of the above circumstances, and its purpose is to obtain a stable hot water tap temperature without changing the tap water temperature even if the supplied water pressure changes, and to provide hot water at a set temperature from the beginning of hot water tap. The objective is to provide a bypass mixing type water heater that can supply water.

[Means for Solving the Problems] In order to achieve the above object, the present invention exchanges heat obtained by burning fuel with water, as shown in FIG.
A heat exchanger 1 that heats water, a bypass waterway 2 that bypasses the heat exchanger 1, and a heat exchanger 1 and a bypass waterway 2 that bypass the heat exchanger 1 and the bypass waterway 2, and A throttle 3 that regulates the total amount of water passing through the vessel 1 and the bypass waterway 2 is provided in the bypass waterway 2, and the amount of water passing through the bypass waterway 2 is adjusted by adjusting the degree of opening. Throttle valve 4, water input amount, set temperature,
Throttle valve control means 5 that determines the opening degree of the throttle valve 4 necessary for the hot water to reach the set temperature based on the incoming water temperature, etc., and the opening degree correction means 6 that corrects the opening degree of the throttle valve 4 based on the hot water exit temperature.
, and a storage means 7 for storing the amount of correction by the opening correction means 6, and when starting the opening of the throttle valve 4, taking into account the amount of correction during the previous tapping stored in the storage means 7. The technical means is to include a control device 8 that determines the degree.

[Effect] The time when the hot spring starts will be explained.

When hot water starts to be dispensed, the throttle valve control means determines the opening degree of the throttle valve necessary to obtain the set temperature from the amount of water entering, the set temperature, the water entering temperature, and the like. The opening degree determined by the throttle valve control means takes into account the opening degree corrected by the opening degree correcting means at the time of the previous tapping, which is stored in the circuit storage means.

As a result, an error between the hot water tap temperature and the set temperature due to variations in appliances, etc. is detected immediately after hot water tap starts.

[Effects of the Invention] According to the present invention, immediately after the start of hot water dispensing, errors caused by variations in appliances, etc. are corrected by the opening degree of the throttle valve. Therefore, even if there are variations in appliances, hot water at the set temperature can be supplied every time hot water is tapped.

Embodiment Next, a bypass mixing type water heater of the present invention will be described based on an embodiment shown in the drawings.

Figure 2 shows a schematic diagram of a bypass mixing type gas water heater.

This gas water heater is broadly divided into a combustion section 1o, a waste supply pipe 20, a water pipe 30, and a control device 4o.

The combustion section 10 includes a combustion case 12 in which a ceramic surface combustion type burner 11 is disposed, and this combustion case 12.
The combustion air that is not guided into the combustion case 12 by the blower 13 is discharged as combustion gas from an exhaust port (not shown) after combustion.

The gas supply pipe 20 is for supplying fuel waste to a nostle 21 that opens on the inner periphery of the centrifugal fan 14 of the blower 13, and sequentially connects the original solenoid valve 22, the main solenoid valve 23, and the proportional valve 24 from the upstream side. It is provided. The downstream side of the proportional valve 24 is branched into two parts, one of which is provided with a switching solenoid valve 25 and the other with an orifice 26. Note that the main solenoid valve 22, the main solenoid valve 23, and the switching solenoid valve 25 open and close the gas supply pipe 20 by energization control, and the proportional valve 24 opens and closes depending on the amount of energization. This is to adjust the amount of waste supplied to 21.

The water pipe 30 has one end connected to a water supply source and the other end connected to a hot water supply inlet, and exchanges heat generated by combustion of waste from the burner 11 with water flowing inside. The heat exchanger 31 heats the water passing through the heat exchanger 31, and the bypass water channel 32 bypasses the heat exchanger 31.

The 4-stream water pipe 30 at the branch point between the heat exchanger 31 and the bypass waterway 32 is equipped with a throttle function of the present invention that regulates the total amount of water passing through the heat exchanger 31 and the bypass waterway 32, and a cabana. Electric water flow control device 33 combined with valve function
is provided. Further, the bypass waterway 32 is also provided with a throttle valve 34 that adjusts the amount of water passing through the bypass waterway 32 by varying its opening degree.

Note that the throttle of the electric water flow control device 33 is set to be the same as or smaller than the throttle valve 34 in order to regulate the total amount of water passing through the heat exchanger 31 and the bypass waterway 32. Further, the throttles of the electric water flow control device 33 and the throttle valve 34 are provided to be variable, and as one stage of adjustment, a geared motor drives a valve body that can open and close the water channel.

As shown in FIG. 3, the control device 40 is composed of a microcomputer 41, a relay circuit 42, and a drive circuit 43, and controls the burner 11 according to the outputs of a controller 44 and various sensors operated by the user. Sparker 45, original solenoid valve 22, main solenoid valve 23, proportional valve 24, switching solenoid valve 25, electric water flow control device 33,
The throttle valve 34 is energized and controlled.

Various sensors of the control device 40 are linked to a flame rod 46 and a thermocouple 47 for detecting the flame of the burner 11 and the air-fuel ratio, an electric water flow control device 33, and a valve body of the throttle valve 34 to detect the opening degree. potentiometers 48, 41) to detect the rotational speed of the blower 13, and an air volume detection sensor 50. Heat exchanger 31 and bypass waterway 32
An inlet water temperature sensor 51 detects the temperature of water flowing into the water, a hot water temperature sensor 52 detects the temperature of the hot water that has passed through the heat exchanger 31, and an outlet water temperature sensor 52 that detects the temperature of the mixed hot water that has passed through the heat exchanger 31 and the bypass waterway 32. It includes a temperature sensor 53, a water amount detection sensor 54 that detects the amount of water flowing into the heat exchanger 31 and the bypass waterway 32.

Next, the combustion control and water amount control by the microcombi J-41 will be briefly explained.

For combustion control, when the user operates a bell connected to the hot water supply inlet and a water flow is generated in the water pipe 30, the water amount detection sensor 54
The rotating body inside rotates and combustion begins. The amount of combustion is determined by the amount of water obtained by various sensors, the temperature of the inlet water, the temperature of the mixed water from the heat exchanger 31 and the bypass waterway 32, etc., so that the outlet temperature set by the controller 1 to the roller 44 can be obtained. The blower 13 is controlled to be energized so as to supply the burner 11 with an air volume corresponding to the determined combustion amount.

Then, the proportional valve 24 and the switching solenoid valve 25 are controlled to be energized so that a gas amount corresponding to the rotational speed of the blower 13 and the temperature of the flame of the burner 11 is obtained.

The throttle valve 34 also controls the inlet water temperature so that the temperature of the hot water in the heat exchanger 31 is maintained above a temperature (for example, 60° C.) at which water generated by combustion (drain water) does not adhere to the heat exchanger 31. The opening is fixed at an appropriate opening calculated from the temperature of the hot water passing through the heat exchanger 31 and the temperature of the hot water exiting the water.

Note that the opening degree of the throttle valve 34 is fixed when water enters 4i1. is released or the set temperature is low], and the throttle valve 34 is controlled to be energized so that the opening degree is calculated according to the decrease in the amount of water input and the decrease in the set temperature.

Further, the electric water flow rate control device 33 is energized and controlled so as not to exceed the maximum flow rate required to obtain the hot water temperature.

The water heater of this embodiment has a throttle and a cabana valve function in the flow at the branch part of the heat exchanger 31 and the bypass waterway 32 to regulate the total amount of water passing through the heat exchanger 31 and the bypass waterway 32. An electric water flow control device 33 is provided. Therefore, even if the water pressure passing through the water heater changes, the mixing ratio does not change. As a result, the temperature of the hot water flowing out is stabilized.

On the other hand, the computer 41 includes a throttle valve control means 55, an opening correction means 56, and an L storage means 57 of the present invention.

has been programmed.

The throttle valve control means 55 sets the opening degree of the throttle valve 34 by feedforward so that the outlet water temperature becomes the set temperature. Detected inlet water temperature, +-
The degree of opening is determined based on the amount of water that is not detected by the i-detection sensor 4, the amount of combustion in the combustion section 10, and the like.

The opening correction means 56 operates when the outlet temperature does not match the set temperature at the opening determined by the throttle valve control means 55 due to variations in equipment or the like. This means that when an error occurs between the tapped water temperature and the set temperature, a correction amount is determined to eliminate this error, and the opening degree determined by the throttle valve control means 55 is increased or decreased according to this correction amount. It is.

The storage means 57 stores the average value of the correction amount of the opening degree correction means 56 during hot water tapping, or the correction amount immediately before the end of hot water tapping.

Then, the correction amount stored in the storage means 57 is set as the initial value of the opening degree correction means 56 at the start of the next hot water dispensing.

As described above, when hot water starts to be tapped, the correction amount stored in the storage means 57 is given as the initial value of the opening correction means 56, and added to the opening determined by the feed forward in the throttle valve control means 55. be done. Immediately after the start of hot water dispensing, the error between the dispensing hot water temperature and the set temperature due to variations in appliances, etc. is corrected.

As a result, the bypass mixing water heater of this example has
It is possible to stably supply hot water at a set temperature without being affected by variations in appliances each time hot water is dispensed.

(Modified example) This embodiment C shows an example in which the diaphragm is variable.
It is also possible to use a fixed aperture. Needless to say, it is good to separate it from the cabana valve.

Although the throttle was provided upstream of the branching portion between the heat exchanger and the bypass waterway, it may also be provided downstream of the converging portion.

Although we have shown an example in which waste is used for combustion, the present invention may also be applied to water heaters that use liquid fuel such as heavy oil or fuel oil.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is a schematic configuration diagram of a bypass mixing type gas water heater, and FIG. 3 is a schematic block diagram of a control device. In the diagram 1...Heat exchanger 2.Bypass waterway 3...
Throttle 4... Throttle valve 5... Throttle valve control f stage 6... Opening correction means 7 Memory means 8... Control device agent Ken Ishiguro

Claims (1)

[Claims] 1) (a) A heat exchanger that heats water by exchanging heat obtained by combustion of fuel with water; (b) A bypass waterway that bypasses the heat exchanger; (c
) upstream of the branching point between the heat exchanger and the bypass waterway;
or a constrictor downstream of the confluence part that regulates the total amount of water passing through the heat exchanger and the bypass waterway; (e) a throttle valve control means that determines the opening degree of the throttle valve necessary to obtain the set temperature from the amount of water entering, the set temperature, the water entering water temperature, etc.; An opening correction means for correcting the opening of the throttle valve, and a storage means for storing the correction amount by the opening correction means, and when starting hot water dispensing, the correction amount for the previous hot water tapping stored in the storage means is taken into account. and a control device that determines the opening degree of the throttle valve.