Storage type water heating method and storage type water heater

Abstract

According to the present invention, hot water having a desired temperature can be generated in a short time by forcibly mixing low temperature water with high temperature water, the capacity of a hot water storing tank may be a about half of that of a conventional hot water storing tank, and a water heater can be downsized and made lightweight, and the manufacturing cost and installation cost thereof can be saved. A hot water storing tank 1 has a water supply port on a base plate 2B side, and a water supply port 4 on a top plate 2C side. A suction port 14 is formed in the hot water storing tank 1 so as to be positioned at the same height as or lower than the water supply port 3, and a jet port 15 is formed in the hot water storing tank 1 so as to be positioned in the vicinity of the water supply port 3. A hot water generating and jetting device 11 having a circulation pump 13 connected to the suction port 14 and the jet port 15 includes a casing 12, a temperature sensor 16, an electric heat type water heater 17 and a control panel 18.

Description

TECHNICAL FIELD

The present invention relates to a storage type water heating technology, more particularly, it relates to a storage type water heating method and storage type water heater in which the supply amount of hot water is secured, while a hot water storing tank is downsized, and the heat source cost can be saved.

BACKGROUND ART

As shown in FIG. 4, a conventional storage type water heater includes: a hot water storing tank 51; a water supply port 52 provided in a body part 51B so as to be positioned near a bottom 51A; a water supply port 53 provided in a top plate 51C; and, a rod-shaped sheath heater 54 inserted at the bottom side of the hot water storing tank 51. Additionally, when water in the hot water storing tank is heated by the sheath heater 54, generated hot water slowly rises by natural convection, and thus a high temperature water region HW having a temperature of, for example, about 98° C., and a low temperature water region LW are generated at the upper part and lower part in the hot water storing tank 51, respectively. Further, it is found that distinct temperature layers W₁, W₂, . . . Wn are formed via temperature layer interfaces S1, S2, . . . Sn respectively, each temperature difference between the temperature layers being about 10° C.

The temperature layers formed in the hot water storing tank indicate the temperature of the hot water in the hot water storing tank is consistently uneven. However, this problem has not yet been clearly solved.

DISCLOSURE OF THE INVENTION

Since temperature layers W₁, W₂, . . . Wn are thus formed in hot water in a hot water storing tank 51, each temperature difference between the temperature layers being about 10° C., the hot water having a temperature of, for example, 85° C. or more, which is usable as hot water, is about half of the whole capacity of the hot water storing tank 51. Accordingly, the following problems remain: first, a large hot water storing tank having a capacity twice as large as that of a conventional tank must be used in order to secure the supply amount of hot water per unit time; second, price and installation construction cost of the hot water storing tank are high; third, a wide space is required for installation; and, fourth, since the capacity of the hot water storing tank is large, it takes time to obtain hot water having a desired temperature, and cost of heat source such as power consumption is high.

In the inventor's consideration regarding the temperature layers in generating hot water with conventional technology, and in view of the above problems, the present invention was made through the inventor's diligent research. It is an object of the present invention to provide a storage type water heating method and storage type water heater, wherein: the temperature layers formed by heating low temperature water are forcibly mixed by jetting high temperature water, temperature layer interfaces are destroyed, and thus the hot water having the desired temperature can be generated in a short time, hot water generated so as to wholly have an approximately evenly set temperature can be stored in the hot water storing tank, and the cost of the heat source can be saved; and, since the capacity of the hot water storing tank may be about half of that of a conventional tank, the tank can be downsized and made lightweight, and thus manufacturing cost and installation cost can be saved, and a space for installation can be cut in half.

In order to achieve the above object, in the present invention according to claim 1, a hot water generating and jetting device is externally attached to a hot water storing tank having a water supply port and a hot water supply port, sucking water, generating hot water by heating, and jetting are repeated between the hot water generating and jetting device and the hot water storing tank, the temperature layers generated by the hot water in the hot water storing tank are forcibly mixed so that the temperature layer interfaces are destroyed, and approximately even high temperature water is generated in the hot water storing tank, whereby the hot water storing tank can be downsized.

Additionally, in the present invention, water in the hot water storing tank supplied from the water supply port is heated by the heat source while being circulated by a circulation pump between a suction port and a jet port that are provided at the bottom side of the hot water storing tank, the heated water is jetted from the jet port and forcibly mixed with the water in the hot water storing tank so that hot water having an approximately even temperature is generated, and the generated hot water is further heated to a desired temperature by the heat source while being circulated by the circulation pump, and is supplied outward from the water supply port provided at the upper side of the hot water storing tank.

Further, the present invention includes: the hot water storing tank having the water supply port at the bottom side of the tank body, and the water supply port at the upper side; and, a hot water generating and jetting device connected to the hot water storing tank. The hot water generating and jetting device has the circulation pump communicating with the suction port formed in the hot water storing tank so as to be positioned at the same height as or lower than the water supply port, and with the jet port formed in the hot water storing tank separately from the suction port, heats the water sucked from the suction port by the heat source, generates the hot water having an approximately even temperature in a manner that the heated water is jetted from the jet port to be forcibly mixed with the water in the hot water storing tank, and further circulates and heats the generated hot water to a desired temperature while detecting the temperature of the generated hot water by a temperature sensor.

Furthermore, the hot water generating and jetting device includes: the circulation pump for circulating water by sucking and jetting between the device and the hot water storing tank; the heat source for heating the water sucked by the circulation pump; the temperature sensor for detecting the temperature of the water sucked from the hot water storing tank; and, a control panel for stopping operation of the heat source in accordance with a signal transmitted from the temperature sensor, the signal indicating the sensor has detected the temperature of the water in the hot water storing tank has reached the desired temperature.

Additionally, the jet port may be formed at the bottom of the hot water storing tank.

The above and other objectives and features of the present invention will be clearly understood in consideration of the following description with reference to the accompanying drawings showing best modes for carrying out the present invention as an example.

EFFECT OF THE INVENTION

As described above, the following effects are obtained by the present invention.

(1) In a conventional storage type water heater, temperature layers prevent hot water having an even temperature from being generated. However, according to the present invention, since high temperature water is jetted into a hot water storing tank and forcibly mixed with low temperature water so that the temperature layers are prevented from being generated and temperature layer interfaces are destroyed, desired hot water having an even temperature can be generated in a short time, and heating time is shortened so that the cost of a heat source can be saved.

(2) The high temperature water is jetted into the hot water storing tank and forcibly mixed with the low temperature water so that high temperature water can be generated which has an approximately even temperature throughout the whole of the hot water storing tank. Therefore, the capacity of the hot water storing tank may be about half of that of a conventional hot water storing tank even if both capabilities of supplying hot water are the same, a water heater of the present invention can be downsized and made lightweight, and thus the manufacturing cost and installation cost of the heater can be reduced, and a space for installation of the heater can be reduced by approximately half.

(3) A hot water generating and jetting device includes: a circulation pump for circulating water by sucking and jetting between the device and the hot water storing tank; a heat source for heating the sucked water; a temperature sensor for detecting the temperature of the sucked water; and, a control panel for stopping operation of the heat source in accordance with a signal transmitted from the temperature sensor, the signal indicating the sensor has detected the temperature of the water in the hot water storing tank has reached the desired temperature. Since the constitution of the device is relatively simple, the water heater is securely operated, does not break down, and the manufacturing cost thereof is saved.

(4) Since a jet port of the high temperature water is formed at the bottom of the hot water storing tank, jet pressure of the high temperature water does not prevent water supplied from a lateral water supply port from flowing into the tank. Additionally, since the hot water is forcibly mixed with the high temperature water so that no temperature layer interface is formed, desired high temperature water can be speedily generated.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 and FIG. 2 show a First Embodiment, FIG. 1 is a perspective view of a storage type water heater, and FIG. 2 is a figure showing an inner structure of the storage type water heater. FIG. 3 is a view showing an inner structure of a storage type water heater according to a Second Embodiment. FIG. 4 is a diagram showing a hot water generation state of a conventional storage type water heater.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In the figures, the reference numeral 1 denotes a hot water storing tank made of stainless steel or high strength synthetic resin formed so as to be vertically long. The hot water storing tank 1 includes: a tank body 2 constituted by a cylindrical body part 2A, a bottom plate 2B for sealing the lower end of the body part 2A, and a top plate 2C for sealing the upper end of the body part 2A; a water supply port 3 formed on the lower end side of the body part 2A of the tank body 2 and near the bottom plate 2B; and, a water supply port 4 formed at the approximate center of the top plate 2C. Additionally, a water supply pipe 5 such as a water pipe is connected to the water supply port, and a hot water supply pipe 6 for supplying hot water to a water faucet (not shown) is connected to the water supply port 4.

The reference numeral 11 denotes a hot water generating and jetting device connected to the hot water storing tank 1 via a pipe. The reference numeral 12 denotes a box-shaped casing constituting the hot water generating and jetting device 11, and is attached to an outer surface of the body part 2A of the hot water storing tank 1 by proper means such as screwing. Moreover, the casing 12 may be attached to a wall, etc., in the vicinity of the hot water storing tank 1.

The reference numeral 13 denotes a circulation pump provided in the casing 12. A suction pipe 13A of the circulation pump 13 is connected to a suction port 14, and a jet pipe 13B of the circulation pump 13 is connected to a jet port 15. Here, the suction port 14 is formed in the body part 2A on the bottom plate 2B side of the hot water storing tank 1 so as to be approximately opposite to the water supply port 3. Additionally, the jet port 15 is formed at a position not opposite to the suction port 14 and separately upward from the suction port by several tens of centimeters, and the circulation pump 13 repeats sucking and jetting water and hot water in the hot water storing tank 1 via the suction port 14 and the jet port 15 to circulate the water and hot water.

The reference numeral 16 denotes a temperature sensor provided in the suction pipe 13A. The temperature sensor 16 detects the temperature of the water (hot water) sucked from the lower side of the hot water storing tank 1 through the suction pipe 13A via the suction port 14 to transmit a detection signal to the following control panel 18.

The reference numeral 17 denotes an electric heat type water heater which is positioned on the jet side relative to the circulation pump 13 and is connected to the pump via a communicating pipe 13C. In the electric heat type water heater 17, an electric heater (not shown) is provided in a can body 17A, and a power source switch, which is connected to the following control panel 18 via signal wires (not shown), is provided on the electric heater.

Additionally, the reference numeral 18 denotes the control panel provided in the casing 14. The control panel 18 has the functions of: setting the temperature of hot water to be supplied to an arbitrary temperature, for example, 85° C. or 90° C.; deciding a difference between the current temperature and the set temperature based on a temperature detection signal transmitted from the temperature sensor 16; and, transmitting a signal for energizing the electric heater to the power source switch based on the decided difference in temperature, or transmitting a signal for stopping energizing of the electric heater to the power source switch in the case where it is decided the difference in temperature is zero.

In the thus constituted storage type water heater of the embodiment, the water supplied to the hot water storing tank 1 through the water supply pipe 5 is sucked by the circulation pump 13, heated into hot water while flowing in the electric heat type water heater 17, and jetted into the hot water storing tank 1 from the jet port 15. In this case, since the suction port 14 is formed opposite to the water supply port 3, low temperature water supplied to the hot water storing tank 1 from the water supply port 3 is speedily sucked by the circulation pump 13, and thus the hot water in the hot water storing tank 1 is, as much as possible, prevented from being cooled by the low temperature water.

On the other hand, the jet port 15 is provided at a position not opposite to the water supply port 3 and appropriately separated from the suction port 14 so that supplying water from the water supply port 3 is not obstructed by water pressure of the hot water jetted from the jet port 15. Additionally, high temperature water is jetted to the low temperature water in the hot water storing tank 1 so that the temperature layers formed by heating the low temperature water are forcibly mixed and the temperature layer interfaces are destroyed, and thus the low temperature water and the high temperature water can be effectively mixed with each other. Accordingly, hot water having a set even temperature can be generated in the hot water storing tank 1. As described above, circulation operation is performed that the low temperature water is sucked by the circulation pump 13 and heated into the high temperature water to be jetted between the hot water storing tank 1 and the electric heat type water heater 17, and that the temperature layers are forcibly mixed and the temperature layer interfaces are destroyed, and thus the water heated to the set approximately even temperature can be speedily stored in the hot water storing tank 1.

Since the hot water storing tank 1 is filled with hot water having the approximately even temperature from the top to the bottom as described above, it is unnecessary to use a hot water storing tank having a capacity twice as large as that of the hot water storing tank 1. Additionally, since the low temperature water and the high temperature water are forcibly mixed with each other, the speed of the temperature rise of the water is high, hot water having a desired temperature can be generated in a short time, and the cost of power consumption can be saved by shortening the heating time.

Comparing the water heater according to the embodiment with a conventional water heater shown in FIG. 4, the supply amount of hot water of the water heater of the embodiment is 600 l, and that of the conventional water heater is 240 l, in the case where, for example, both the capacities of the hot water storing tanks 1 and 51 are 300 l, both the temperatures of supplied water are 45° C. That is, it is revealed that the water heater of the embodiment has a capability to supply hot water twice as fast as that of the conventional water heater.

FIG. 3 shows a Second Embodiment. Moreover, the same symbols are attached to components identical to the components of the First Embodiment, and a description thereof will be omitted. In FIG. 3, the reference numeral 21 denotes a hot water generating and jetting device connected to the hot water storing tank 1, 22 denotes a box-shaped casing constituting the hot water generating and jetting device 21, and 23 denotes a circulation pump provided in the casing 22. A suction pipe 23A of the circulation pump 23 communicates with a suction port 24, and a jet pipe 23B of the circulation pump 23 communicates with a jet port 25.

Here, the suction port 24 is formed in the body part 2A of the hot water storing tank 1 opposite to the water supply port 3, and the jet port 25 is formed at the approximate center of the bottom plate 2B of the hot water storing tank 1 so that a jetting direction of the jet port 25 becomes orthogonal to a supplying water direction of the water supply port 3. Additionally, the circulation pump 23 circulates the water in the hot water storing tank 1 via the suction port 24 and the jet port 25.

The temperature sensor 16 is provided in the suction pipe 23A, and the electric heat type water heater 17 is provided in the middle of the jet pipe 23B of the circulation pump 23. Additionally, the control panel 18 is provided in the casing 22, and connected to the electric heat type water heater 17 and the temperature sensor 16 via signal wires (not shown).

In the thus constituted storage type water heater of the embodiment, the low temperature water is made to impact and forcibly mix with the high temperature water in the hot water storing tank 1 so that the temperature layers are not formed, and thus the hot water having the desired temperature can be speedily generated. In this point, the water heater of the embodiment is basically the same as that of the First Embodiment. However, according to the embodiment, since the high temperature water generated by the hot water generating and jetting device 21 is jetted upward from the jet port 25 open-formed in the bottom plate 2B of the hot water storing tank 1 so that flow in a rising direction is positively formed in the hot water storing tank 1, the high temperature water flows upward and downward to be mixed with the low temperature water, and thus hot temperature water can be rapidly generated.

Moreover, although the electric heat type water heater 17, which has the electric heater as a heat source, for generating the hot water is employed in each embodiment, a gas combustion type water heater or an oil combustion type water heater may be employed as the heat source in the present invention.

Claims

1. A storage type water heating method capable of downsizing a hot water storing tank, comprising the steps of:

repeating sucking water, generating hot water by heating, jetting the hot water between a hot water generating and jetting device, which is externally attached to the hot water storing tank having a water supply port and a hot water supply port, and the hot water storing tank;

destroying temperature layer interfaces by forcibly mixing temperature layers generated by the hot water in the hot water storing tank; and,

generating high temperature water having an approximately even temperature in the hot water storing tank.

2. A storage type water heating method for generating hot water to be supplied outward from the water supply port provided at an upper side of the hot water storing tank, comprising the steps of: heating water in the hot water storing tank supplied from the water supply port by a heat source while circulating the water by a circulation pump between a suction port and a jet port that are provided at a bottom side of the hot water storing tank; jetting the heated water from the jet port and forcibly mixing it with the water in the hot water storing tank so that hot water having an approximately even temperature is generated; and, further heating the generated hot water to a desired temperature by the heat source while circulating the generated hot water by the circulation pump.

3. A storage type water heater comprising: a hot water storing tank having a water supply port at a bottom side of a tank body, and a water supply port at an upper side of the tank body; and, a hot water generating and jetting device connected to the hot water storing tank, wherein the hot water generating and jetting device has a circulation pump communicating with a suction port formed in the hot water storing tank so as to be positioned at the same height as or lower than the water supply port, and with the jet port formed in the hot water storing tank separately from the suction port, heats water sucked from the suction port by the heat source, generates hot water having an approximately even temperature in a manner that the heated water is jetted from the jet port to be forcibly mixed with water in the hot water storing tank, further circulates the generated hot water while detecting temperature of the generated hot water by a temperature sensor, and heats the hot water to a desired temperature by the heat source.

4. The storage type water heater according to claim 3,

wherein the hot water generating and jetting device includes: a circulation pump for circulating water by sucking and jetting between the device and the hot water storing tank; a heat source for heating the water sucked by the circulation pump; a temperature sensor for detecting temperature of hot water sucked from the hot water storing tank; and, a control panel for stopping operation of the heat source in accordance with a signal transmitted from the temperature sensor, the signal indicating the sensor has detected the temperature of the water in the hot water storing tank has reached a desired temperature.

5. The storage type water heater according to claim 3,

wherein the jet port is formed at a bottom of the hot water storing tank.