JP3757561B2 - Direct pressure oil water heater - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to downsizing and improvement of hot water supply characteristics of a direct pressure oil water heater used for domestic hot water supply and heating equipment.
[0002]
[Prior art]
A general direct pressure oil water heater will be described with reference to FIG.
[0003]
In FIG. 5, 1 is a heat exchanger having plate fins, and 2 is attached to the heat exchanger 1 by a burner. Reference numeral 3 denotes a water supply port fixed to the water pipe. 4 is a flow rate sensor for detecting the flow of water and is connected to the water supply port 3. A water supply pipe 5 connects the heat exchanger 1 and the flow sensor 4. Reference numeral 6 denotes a hot water supply port, which is an outlet portion of a product that supplies the water that has become hot water in the heat exchanger 1 by the combustion of the burner 2 to the kitchen or bathroom. A hot water supply pipe 7 connects the hot water supply port 6 and the heat exchanger 1. A bypass pipe 8 directly connects the water supply pipe 5 and the hot water supply pipe 7, and a bypass electromagnetic valve 9 is provided in the middle of the bypass pipe. Reference numeral 10 denotes a hot water supply thermistor provided at the outlet of the heat exchanger 1 for hot water temperature control. A water amount control valve 11 is provided in the vicinity of the hot water supply port 6.
[0004]
[Problems to be solved by the invention]
Direct pressure type oil water heaters are increasing year by year as the points of appeal are the comfort of strong hot water shower pressure, the miniaturization of products, and the space saving by weight reduction. However, because of the characteristics of the product, in order to detect that the water has flowed and burn it, the flow rate sensor 4 is used as the sensor, and in order to prevent after-boiling due to the residual heat of combustion that occurs when reheating the hot water after stopping hot water supply, A bypass pipe 8 and a bypass solenoid valve 9 are provided between the pipe 5 and the hot water supply pipe 7, and the bypass solenoid valve 9 is opened and closed by a hot water supply thermistor 10 set at the outlet of the heat exchanger when the post-boiling temperature at the time of reheating is high. This prevents hot water from being heated by boiling after reheating. In addition, when a hot water supply load exceeding the capacity of the water heater is requested, the hot water set temperature is prevented from being reached, and the amount of water is controlled in the vicinity of the hot water outlet in order to maintain the hot water set temperature. A water amount control valve 11 was provided.
[0005]
However, in order to cope with further downsizing of the product, individual installation spaces for the flow sensor 4, the bypass solenoid valve 9, and the water amount control valve 11 are necessary, and there is a limit to downsizing. In addition, since the parts are dispersed individually, material costs and water-sealing properties are required at the connecting portions between the parts, and the manufacturing cost is high.
[0006]
Further, two bypass solenoid valves 9 are used to cope with the change in the post-boiling temperature, one bypass solenoid valve is opened as shown in FIG. 6, and when the post-boiling temperature is high, the other bypass solenoid valve is opened. However, such a two-stage opening / closing control for the bypass solenoid valve cannot completely cope with the change in the post-boiling temperature.
[0007]
On the other hand, the timing to close after opening the bypass solenoid valve was closed at a constant temperature of the hot water supply thermistor regardless of the flow rate at the time of reheating, so the closing timing was early and the post-boiling temperature was high at a low flow rate. On the other hand, the valve was closed in a state, and at the time of a large flow rate, the timing was late and the valve was closed after hot water from after boiling passed, so that water from the feed water directly flowed into the hot water supply, and cold water sometimes came out.
[0008]
This invention solves the said subject and provides the structure which aims at the size reduction of a product and the drastic improvement of a hot-water supply characteristic.
[0009]
[Means for Solving the Problems]
In order to solve this problem, the present invention includes a water supply unit, a hot water supply unit, a heat exchanger, and a burner, and a flow rate sensor is provided in the water supply unit, and a heat exchanger side and a hot water supply unit side are provided on the downstream side of the flow rate sensor. A water amount control valve is provided that forms a bi- directional passage that branches into the heat exchanger and limits the amount of water in the heat exchanger side passage ;
Two bypass valves for controlling the amount of water in the hot water supply side passage of the branch passage are provided in parallel, and the flow rate sensor, the water amount control valve, and the bypass valve are arranged in a linear position , and a connection portion with a water supply port, The integrated body has a connection portion with a water supply pipe and a connection portion with a bypass pipe .
[0010]
With the above configuration, the direct pressure oil water heater of the present invention can be greatly reduced in size as a product by integrating and arranging the individual spaces of the flow sensor, the bypass valve, and the water amount control valve in a linear position.
[0011]
In addition, the bypass passages of the two bypass valves are set to have a small diameter and a large diameter, and the bypass valve opening drive is variable with respect to the heat exchanger outlet temperature, and the bypass valve is driven to open and then closed. The hot water supply performance can be greatly improved by changing the closing temperature by the small flow rate, the medium flow rate and the large flow rate when the temperature at the outlet of the heat exchanger is descending on the basis of the feed water start signal.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Invention of Claim 1 of this invention is equipped with the water supply part, the hot water supply part, the heat exchanger, and the burner, provided the flow sensor in the said water supply part, and the heat exchanger side and the hot water supply part in the back flow side of this flow sensor. Forming a two-way passage branching to the side and restricting the amount of water in the heat exchanger side passage , and providing two bypass valves in parallel for controlling the amount of water in the hot water supply side passage of the branch passage , In addition, the flow sensor, the water amount control valve and the bypass valve are arranged in a linear position , and an integrated body having a connection portion with a water supply port, a connection portion with a water supply pipe, and a connection portion with a bypass pipe is provided. Yes, the product can be downsized.
[0013]
Further, the invention according to claim 2 includes a flow sensor, a water amount control valve, and a bypass valve having a combustion air blower and an integrated body in a space formed by a motor and a body case constituting the combustion air blower. is obtained by placing, further downsizing can be promoted.
[0014]
According to a third aspect of the present invention, the bypass passages of the two bypass valves are set to have a small diameter and a large diameter, and the bypass valve is driven according to the degree of the temperature rise of the heat exchanger outlet temperature. When opening the bypass valve on the small diameter side, (b) opening the bypass valve on the large diameter side after opening the bypass valve on the small diameter side and simultaneously closing the small diameter bypass valve, (c) bypassing on the small diameter side When opening only the large-diameter side bypass valve after opening the valve and simultaneously closing the small-diameter bypass valve, and simultaneously opening the small-diameter side and the large-diameter side, (d) after opening the large-diameter side bypass valve, When opening large bypass valves at the same time, (e) distinguishing between small diameter and large diameter bypass valves at the same time, it is possible to respond to changes in the post-boiling temperature due to differences in hot water supply stop time, combustion load, etc. it can.
[0015]
Furthermore, the invention according to claim 4 is a small flow rate when the temperature of the hot water supply thermistor at the outlet of the heat exchanger is descending on the basis of the water supply start signal after the bypass valve provided on the hot water supply side is opened and closed. In addition, the closing temperature is variable by medium flow and large flow, preventing the valve from closing at a high post-boiling temperature due to the timing of closing the bypass valve too early, and hot water due to post-boiling due to timing delays. Since the valve is closed after the water has passed, it is possible to prevent water from the water supply from flowing directly into the hot water supply and out of the cold water.
[0016]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
[0017]
Example 1
FIG. 1 is an overall configuration diagram of Embodiment 1 of the present invention. FIG. 2 is a sectional side view of the main part.
[0018]
In the figure, 11 is a heat exchanger having plate fins, and 12 is attached to the heat exchanger 11 by a burner. A water supply port 13 is fixed to the water pipe. 14 is a flow sensor for detecting the flow of water, and 15 is an amount of water that restricts the amount of water to the inner heat exchanger side of the two-way passage that branches downstream of the flow sensor 14 to the heat exchanger side and the hot water supply side. Control valves 16 and 17 are bypass valves for controlling the amount of water to the hot water supply section, and are provided with a small-diameter bypass valve 16 and a large-diameter bypass valve 17 facing each other. The two bypass valves, the flow sensor 14, the water amount control valve 15, the small-diameter bypass valve 16, and the large-diameter bypass valve 17, are arranged as an integrated body 18 in a linear position. A water supply pipe 19 connects the heat exchanger 11 and the integrated body 18. Reference numeral 20 denotes a hot water supply port, which is an outlet portion of a product that supplies hot water in the heat exchanger 11 due to combustion of the burner 12 to the kitchen or bathroom. A hot water supply pipe 21 connects the hot water supply port 20 and the heat exchanger 11. Reference numeral 22 denotes a bypass pipe that directly connects the integrated body 18 and the hot water supply pipe 21. A hot water supply thermistor 23 is provided at the outlet of the heat exchanger 11 for controlling the hot water supply temperature.
[0019]
Next, the operation and action will be described. The individual spaces of the flow sensor 14, the water amount control valve 15, and the bypass valves 16 and 17 can be greatly reduced in size by being integrated and arranged in a linear position, By reducing the material cost for the joints between the individual parts and reducing the number of water seals, it is possible to obtain manufacturing cost and quality effects.
[0020]
Further, the integrated body 18 having the flow sensor 14, the water amount control valve 15, and the bypass valves 16 and 17 is provided between the combustion air blower 24 where the motor 24 a of the combustion air blower 24 is located and the water heater main body wall 25. Since the dead space is used, the size can be greatly reduced. Further, by providing the bypass valves 16 and 17 facing each other, the water channel resistance of the bypass portion becomes a parallel circuit, and a larger amount of bypass can be secured.
[0021]
In addition, the two bypass valves 16 and 17 are individually set to have a small diameter and a large diameter, and the bypass valves 16 and 17 are opened at the heat exchanger outlet depending on the degree of temperature rise of the heat exchanger outlet temperature. Based on the output from the hot water supply thermistor 23 for hot water temperature control, the control unit 26 opens the bypass valve in the modes shown in FIGS. In the setting mode, (a) when opening the bypass valve on the small diameter side (bypass ratio is about 25%), (b) opening the bypass valve on the large diameter side (bypass ratio is about 42%) after opening the bypass valve on the small diameter side. When opening (c) opening the bypass valve on the large diameter side after opening the bypass valve on the small diameter side, and opening the small diameter side and the large diameter side simultaneously (bypass ratio is about 50%), (d) large diameter side When opening the small diameter and large diameter bypass valves at the same time after opening the bypass valve, (e) distinguishing between opening the small diameter and large diameter bypass valves at the same time, after boiling due to differences in hot water supply stop time and combustion load, etc. It can respond to changes in temperature.
[0022]
Further, the control unit 26 performs the closing drive of the bypass valves 16 and 17 provided on the hot water supply unit side based on the output from the hot water supply thermistor 23 for hot water temperature control provided at the heat exchanger outlet based on the water supply start signal. Control is performed in the modes shown in (a) to (c). That is, when the temperature is descending, 6.5 l / min is distinguished as a small flow rate, 6.5 to 12 l / min as a medium flow rate, and 12 l / min or more as a large flow rate. When the temperature is small, the closing temperature of the small diameter bypass valve 16 is The closing temperature of the small-diameter bypass valve 16 is 5 ° C. higher than the hot water set temperature (b) when the flow rate is 3 ° C. higher than the hot water set temperature (a), and at a medium flow rate. The closing temperature is changed by 7 ° C. higher than the set temperature of the hot water supply (c) to vary the closing temperature. This prevents the valve from closing in a state where the post-boiling temperature is high due to the timing for closing the bypass valves 16 and 17 being too early, and also closes the valve after hot water due to post-boiling has passed due to timing delay. The water from the water supply directly flows into the hot water supply to prevent cold water from coming out.
[0023]
【The invention's effect】
As described above, the present invention has the following effects.
[0024]
According to the first aspect of the present invention, it is possible to greatly reduce the size of the product by integrating the flow sensor, the water amount control valve, and the bypass valve in a linear position, and to improve the quality by reducing the number of connecting portions. And production costs can be reduced.
[0025]
The invention according to claim 2 can be further miniaturized by incorporating the flow sensor, the water amount control valve, and the bypass valve using the motor installation space of the blower for combustion air.
[0026]
In the invention according to claim 3 or 4, the two bypass valves are set to have a small diameter and a large diameter, and the open drive mode of the bypass valve is varied by the post-boiling temperature, and the bypass valve is closed after the open drive. The hot water supply performance can be improved by changing the drive mode according to the flow rate.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a direct pressure oil water heater according to a first embodiment of the present invention. FIG. 2 is a side sectional view of an essential part of the direct pressure oil water heater. FIG. 3 (a) to (e) Mode diagram of bypass valve opening drive in Embodiment 1 [Fig. 4] (a) to (c) Mode diagram of bypass valve closing drive of the same direct pressure type oil hot water supply [Fig. 5] Overall configuration of a conventional direct pressure type oil hot water heater [Fig. 6] Mode diagram of conventional bypass valve opening drive [Explanation of symbols]
11 Heat Exchanger 13 Water Supply Port 14 Flow Sensor 15 Water Flow Control Valve 16 Small Diameter Bypass Valve 17 Large Diameter Bypass Valve 18 Integrated Body 19 Water Supply Pipe 20 Hot Water Supply Port 21 Hot Water Supply Pipe 22 Bypass Pipe 23 Hot Water Supply Thermistor 24 Combustion Air Blower 24a Motor 26 controller

Claims (4)

A water supply unit, a hot water supply unit, a heat exchanger, and a burner are provided, and a flow rate sensor is provided in the water supply unit, and a two-way passage that branches to the heat exchanger side and the hot water supply unit side is formed on the downstream side of the flow rate sensor and A water amount control valve for limiting the amount of water in the exchanger side passage is provided , two bypass valves for controlling the water amount in the hot water supply side passage of the branch passage are provided in parallel, and the flow sensor, the water amount control valve, and the bypass valve are provided. A direct pressure type oil hot water heater that is arranged in a linear position and has an integrated body having a connection portion with a water supply port, a connection portion with a water supply pipe, and a connection portion with a bypass pipe . The direct pressure type oil according to claim 1, further comprising: a combustion air blower , and a flow sensor, a water amount control valve, and a bypass valve that are integrated into a space formed by a motor and a main body case constituting the combustion air blower. Water heater.   The temperature of the hot water thermistor provided at the outlet of the heat exchanger with two bypass valves provided on the hot water supply side is set to have a small diameter and a large diameter and the opening of the bypass valve is based on a water supply start signal. If the temperature at the outlet of the heat exchanger is low, the small diameter bypass valve is opened. If the temperature at the outlet of the heat exchanger is slightly high, the large diameter bypass valve is opened. If it is higher, open both bypass valves at the same time and if the temperature rises gradually, open the small diameter bypass valve and then open only the large diameter bypass valve and simultaneously close the small diameter bypass valve to further increase the temperature. 3. A direct pressure oil water heater according to claim 1 or 2, further comprising a control unit that opens both bypass valves when performing the operation. When the temperature of the hot water supply thermistor provided at the outlet of the heat exchanger is descending on the basis of the water supply start signal, the control unit closes the open valve after the bypass valve provided on the hot water supply side is opened. 4. The direct pressure oil hot water supply machine according to claim 3, wherein the closing temperature is varied by the flow rate.

Images