JPS6315511B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a hot water boiler that spouts high-temperature hot water from the upper part of a hot water storage tank and stratifies the temperature thereof, and relates to a boiler structure that includes a flow rate attenuator at the spouting portion of the high-temperature hot water. Conventional configuration and its problems A conventional hot water boiler is configured as shown in FIG. That is, for a hot water storage tank 3 having a hot water outlet pipe 1 in the upper part and a water supply pipe 2 in the lower part, the circulation pump 4, the heat source part 5, and the hot water supply pipe 8 are sequentially connected to the connecting pipes 6 and 7 from the lower part of the hot water storage tank 3. In addition, it has a hot water boiler structure in which the tip of the hot water supply pipe 8 is connected to the substantially upper part of the hot water storage tank 3 to form a heating circuit. In this structure, high-temperature hot water is ejected from the upper part of the hot water tank 3 and the temperature is stratified. Unless the conditions are modified considerably to reduce the flow rate, convection will become intense and the hot water storage tank 3
The temperature distribution above and below the inside is not uniform. (An example of performance is shown in Figure 2.) Next, in the case of reheating after boiling, since an instantaneous water heater is used as the heating source, the predetermined temperature is maintained during the transient period until the steady state is reached. The following low-temperature water will be spouted out (Figure 3 shows the start-up performance of a typical instantaneous water heater). This will cause a decline. Therefore, when hot water is tapped under this condition, there are problems such as the temperature of the hot water partially falling below the predetermined temperature and deteriorating the hot water tap performance (see Section 4).
An example of performance is shown in the figure). Furthermore, there is a conventional example shown in FIG. 5 that alleviates the latter deterioration in hot water tapping performance. The outline of the configuration is as follows: At the tip of the hot water pipe 8, there is a bottomless distribution tube 15 that is hollow and cylindrical and has small holes 14 throughout the side wall.
There is a structure in which the hot water storage tank 3 is provided at a height from top to bottom in the vertical direction. In this configuration, during the transition period when the instantaneous water heater starts up, the low-temperature water is sent from the top to the bottom of the distribution tube 15 and exchanges heat with the high-temperature hot water in the hot water storage tank 3, resulting in a rise in temperature. In some cases, the distribution cylinder 15
Depending on the ejection conditions, the high-temperature hot water that existed in the tank 3 is sent to the lower part of the tank 3, which disturbs the temperature distribution in the lower part of the tank 3 and reduces the area where the hot water temperature is stable. Problems arise in either case. OBJECTS OF THE INVENTION The present invention is intended to solve these conventional problems, and its first purpose is to minimize the distribution of hot water temperature within the hot water storage tank during boiling. Furthermore, the second purpose is to eliminate a sudden drop in the temperature of hot water.
Furthermore, the third objective is to realize the system with a simple configuration without controlling the circulation pump or controlling the flow rate. Structure of the Invention In order to achieve this object, the present invention provides a hot water boiler that spouts high-temperature hot water from approximately the upper part of the hot water storage tank to create temperature stratification. A bottomed cylindrical flow velocity attenuator with a truncated conical shape and a large number of small through holes formed in the side wall is connected vertically to the hot water storage tank. With this configuration, during boiling, the pressure and flow rate of the circulation pump are attenuated by the flow rate attenuator, and the hot water is uniformly jetted horizontally into the hot water storage tank, preventing convection and achieving temperature stratification of high-temperature hot water. By spouting the low-temperature water at a low flow rate and in a line shape rather than a planar shape toward the bottom, diffusion within the hot water storage tank can be prevented, and a sudden drop in the hot water temperature can be minimized. DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on the drawings of FIGS. 6 to 9. In the drawings, parts that are the same as those in the conventional example shown in FIGS. 1 and 5 are given the same numbers. In the figure, a hot water storage tank 3 with a water supply pipe 2 at the bottom
The water inlet pipe 6 is branched into connecting pipes 6a and 6b from the other lower part through a check valve 10, and the water inlet pipes 6 are connected to circulation pumps 4a and 4b, heat sources 5a and 5b, and connecting pipes 8a and 8, respectively.
They are arranged in the order of b and finally converge in the hot water supply pipe 8, and the hot water supply pipe 8 is located substantially at the upper part of the hot water storage tank 3 to form a heating circuit. In this basic configuration, the flow rate attenuator 12 provided at the tip of the hot water supply pipe 8 has a side wall made of porous material, has a large number of small ejection holes 13, has a bottomed cylindrical inverted truncated cone shape, and has a hot water storage tank 3. It is located substantially above the hot water storage tank 3, and in a vertical direction with respect to the hot water storage tank 3. Next, the hot water storage tank 3 has a mixing chamber 17 whose center protrudes concentrically at the upper end, and the mixing chamber 17
The outlet pipe 1 is taken out from the side wall. moreover,
A temperature thermistor a9 is provided on the lower side wall. In addition, 11a and 11b are flow rate adjustment units installed between the heat sources 8a and 5b and the circulation pumps 4a and 4b, respectively, and temperature thermistors b16a and 16b are installed in the connecting pipes 8a and 8b on the downstream side of the heat sources 5a and 5b.
It is equipped with The operation and effects will be explained below separately for boiling and dispensing. 1 During Boiling When the water temperature in the hot water storage tank 3 is lower than the predetermined water temperature, the temperature thermistor a9 senses it and sends a signal to the circulation pumps 4a and 4b to drive them. When the circulation pumps 4a, 4b are driven, the heat sources 5a, 5b are ignited by detection by flow rate switches (not shown) provided in the heat sources 5a, 5b, and the water is circulated and heated. Thereafter, when the lower part of the hot water storage tank 3 reaches a predetermined hot water temperature, the temperature thermistor a9 senses this and the circulation pumps 4a, 4b stop, and the heat sources 5a, 5b are extinguished as detected by the flow rate switch. In this boiling process, in this embodiment, the capacity of the circulation pumps 4a and 4b is kept constant (the flow rate is constant), and the amount of combustion in the heat sources 5a and 5b is proportionally controlled to increase the temperature of the hot water sent to the hot water supply pipe 8. is kept constant. In other words, temperature thermistor b16
a and 16b send a signal to a proportional valve (not shown) that adjusts the combustion amount when the hot water temperature reaches a predetermined temperature or higher to reduce the combustion amount (TDR combustion) and always maintain the predetermined hot water temperature. From the above, the hot water sent from the hot water supply pipe 8 attenuates the force of the circulation pump with the inverted truncated cone-shaped flow velocity attenuator, and the flow velocity also attenuates, resulting in a nearly stationary spout. Regarding the inward jet distribution, since the jet pressure distribution is made into an inverted truncated cone shape so that the jet pressure distribution is almost uniform in the vertical direction of the flow velocity attenuator, the jet is jetted out uniformly in the horizontal direction. In general, in a bottomed cylindrical flow velocity damping body, when the ejection area of the small hole provided from the vicinity of the inlet toward the tip and the cross-sectional area of the inside of the cylindrical body through which the fluid passes are constant, the following problems occur. arise. That is,
The pressure inside the flow rate attenuator gradually decreases from the inlet toward the tip, and the pressure at the tip increases due to the addition of dynamic pressure, whereas the inlet has only static pressure. <Tip part). From such a thing,

[Formula] But as is clear, the flow velocity is also greater at the tip. This causes a difference in flow velocity distribution between the inlet and the tip, making it impossible to obtain uniform jets from the small holes. On the other hand, as in the present invention, by gradually decreasing the ejection area and the internal passage cross-sectional area from the inlet part to the tip part of the flow velocity attenuator,
This solves the problems mentioned above. That is, the pressure at each part within the flow rate attenuator is thereby approximately constant. In other words, the tip has a small cross-sectional area that is less susceptible to dynamic pressure. From the above, there is no flow velocity distribution from the inlet to the tip of the flow velocity attenuator, and uniform jetting can be obtained. Convection within the hot water storage tank can be prevented, and an upper stratification system for hot water with no temperature distribution is established. The performance in this case is shown in FIG. 2 In the case of hot water dispensing After the hot water in the hot water storage tank 3 has been boiled to the specified temperature, the hot water in the heating circuit has dropped due to the outside temperature and has reached the water temperature (generally 5 degrees Celsius in winter). When the faucet (not shown) at the tip of hot water tap 1 is opened to dispense hot water, low-temperature water is sent from the water supply pipe 2 and is pushed up to the top of hot water tap 1.
A predetermined high temperature hot water is sent out. After that, the temperature thermistor a9 provided on the lower side wall of the hot water storage tank senses the temperature and turns on the circulation pumps 4a, 4.
Send a signal to b to drive it. Circulation pump 4a, 4
When b is driven, the heat sources 5a and 5b begin to ignite and reheating is started. At the beginning of this reheating, low-temperature water during a transient period when the heat source parts 5a and 5b rise is sent to the flow rate attenuator 12. Under this situation, the jetting conditions are close to static pressure with the inverted truncated cone-shaped flow velocity attenuator, and the opening area and diameter of the side wall are located in the direction that decreases toward the bottom, so the temperature is low. The water is not sprayed in a planar shape, but rather in a linear manner towards the bottom. By doing this, it is possible to prevent diffusion over a wide range within the hot water storage tank, and to minimize the sudden drop in the hot water temperature when hot water is tapped (as shown in Figure 9). The resulting hot water boiler can be provided. In addition, in the above embodiment, the hot water supply pipe and the hot water outlet pipe are arranged concentrically, but the present invention is not limited to this configuration, and the hot water supply pipe and the hot water outlet pipe may be separated and provided in the hot water storage tank. Needless to say. Further, the above-mentioned protruding mixing chamber may be provided as necessary and may also serve as the upper part of the hot water storage tank. Effects of the Invention As described above, the hot water boiler of the present invention provides the following effects. 1 The flow velocity attenuator allows the water to eject to near static pressure and eject uniformly in the horizontal direction, making it possible to minimize the temperature distribution within the hot water storage tank, resulting in stable high water temperature in a short period of time. This will improve usability. 2. The inverted truncated cone-shaped flow rate attenuator allows low-temperature water to be ejected in a linear manner, and since there is no diffusion within the hot water storage tank due to the ejection of low-temperature water at close to static pressure, high-temperature hot water with a stable hot water temperature can be obtained. 3. To provide a hot water boiler that is inexpensive because the purpose can be achieved with a simple configuration such as a flow rate attenuator, rather than using a system that linearly controls the circulation pump from startup to a steady state or a system that uses heat-responsive valves. becomes possible. 4. It is possible to provide a hot water boiler with high thermal energy efficiency, which has a hot water storage function that can discharge a large amount of hot water with a stable temperature, and an instantaneous function that can discharge high temperature hot water in a short time.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of a conventional hot water boiler, Figure 2 is a boiling performance diagram of the same as above, Figure 3 is a general start-up performance diagram of an instantaneous water heater, Figure 4 is a hot water output performance diagram of the same as above, Fig. 5 is a schematic diagram of another conventional example, Fig. 6 is a configuration diagram of a hot water boiler according to an embodiment of the present invention, Fig. 7 is an enlarged sectional view of the main parts of the same, and Fig. 8 is a boiling performance diagram of the same. , FIG. 9 is a hot water tapping performance diagram of the same as above. 1... hot water outlet pipe, 3... hot water storage tank, 4a, 4b...
Circulation pump, 5a, 5b... heat source section, 8... hot water supply pipe, 12... flow rate attenuator, 13... small jet hole.

Claims (1)

[Claims] 1. Connect a hot water tank with a hot water outlet pipe at the top and a water supply pipe at the bottom in the order of the water inlet pipe, circulation pump, connecting pipe, heat source, and hot water supply pipe from the other bottom of the tank, and connect the tip of the hot water pipe to the top of the hot water tank. A heating circuit is formed by connecting to the upper part of the hot water supply pipe, and at the tip of the hot water supply pipe, a bottomed cylindrical flow velocity damping body with an inverted truncated conical shape and many small through holes formed in the side wall is communicated vertically to the hot water storage tank. A hot water boiler.