JPS63305060A - Hot water feeding tank - Google Patents

Abstract

PURPOSE:To reduce the degree of holding heat of hot water in a tank being taken out to the tank outside by heat conduction by installing the passage extension part interposed in a cooling passage at a vacuum clearance sorrounding a relatively long hot water running passage and an adiabatic area in a double wall. CONSTITUTION:If a heater 10 is made to work after cooling water is filled up in a tank A from a cooling water passage 4, water inside the tank A is heated and thereby its specific gravity becomes lighter, thus high temperature water is stored in a top wall surface nearby. At time of use of hot water, if cooling water is supplied into the inside of the tank A from the cooling passage 4, upper hot water is thrust into this pipe from an upper opening end of a hot water running passage 3, and it flows to the outside from a hot water takeout port 7. And when cooling water feed is stopped, it is heated up to the specified temperature by the heater 10. Thus, in the hot water stored in the tank A, the degree of its holding heat inside the tank A is sharply reducible from being taken out to the outside of the tank A by conduction, owing to the presence of the passage extension part 4A interposed between a vacuum clearance (a) surrounding the relatively long hot water running passage 3 and the cooling passage 4 at an adiabatic area in a double wall.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention uses an electric heater as a heating source, and can immediately take out a relatively small amount of hot water as needed with low power consumption. This invention relates to a hot water supply tank suitable for defrosting glass, washing hands in toilets, etc.

[Prior Art] In winter, removing frost from the windshield of an automobile is extremely tedious and time-consuming. Therefore, a water heater using a positive temperature characteristic thermistor, etc. was inserted in the middle of the water pipe connecting the water tank and the injection nozzle of the existing windshield water injection system.
114 Methods such as heating the water spray are being considered.

[Problems to be Solved by the Invention] A simple hot water supply system such as the one described above can be assembled into a device that heats water with an electric heater, stores it, and takes it out when needed, for example when washing hands in the coldest months. , can be used very conveniently.

In such devices, it is desirable to use an insulating tank with a vacuum layer interposed between the inner and outer walls in which the heated lagoon is stored.

However, it is necessary to minimize the drop in the temperature of the water in the tank through the pipes that supply and take water out of the tank.

However, these tubes are typically made of metal, and heat escapes through the tube's mounting structure.

The present invention is designed to reduce heat in the tank, especially in the area surrounded by the inner wall.
To provide a hot water supply tank capable of minimizing escape to the outside.

[Means for solving the problems] In order to achieve the above object, the hot water supply tank according to the present invention (a) has a double wall structure of an inner wall and an outer wall,
(b) a tank having a vacuum layer formed between the inner wall and the outer wall; The other end is a hot water flow path that protrudes outside the tank,
(c) a central inner wall surrounding the hot water flow passage via a vacuum gap, integrally formed with the inner wall, and joined only to one end of the hot water flow passage; and (d) a central inner wall portion of the tank; a cold water passageway mounted through the bottom of the inner wall and the bottom of the outer wall, with a passageway extension between the inner wall and the outer wall; and (e) heating for heating the liquid in the tank. We adopted a structure consisting of a vessel.

[Function] In a hot water supply tank having the above configuration, when the heater is activated after the tank is filled with cold water through the cold water passage, the water in the tank is heated and its specific gravity is reduced. High temperature water is stored near the top wall inside.

Next time you want to use the hot water stored in the tank, you can replenish the tank with cold water through the cold water passage, and the water pressure of the supplied cold water will be applied to the bottom of the tank.
The hot water in the upper part of the tank is forced into this pipe from the upper open end of the hot water flow path, and flows out of the tank from the hot water outlet.

When the supply of cold water to the tank is stopped, the supply of cold water to the tank is stopped, and at the same time, the cold water in the tank is heated again to a predetermined temperature by the heater.

The hot water stored in the tank is thermally connected to the outside air through a hot water flow passage and a cold water passage that are installed through the double wall of this tank, but the hot water flow passage is relatively long. Due to the surrounding vacuum gap and the presence of passage extensions interposed in the cold water passage in the insulated area within the double wall, the degree to which the heat retained in the hot water in the tank is carried out of the tank by conduction is significantly reduced. That is, the heat that is about to leak outside from the hot water flow passage is returned to the tank via the vacuum gap, and the passage extension captures the heat that is about to escape to the outside of the tank and returns it to the tank. It functions to return to

[Example] The configuration of the present invention will be specifically described below based on an example shown in the drawings.

Figures 1 to 4 all show an embodiment in which a hot water supply tank according to the present invention is used for defrosting the windshield of an automobile, and Figure 1 is a longitudinal sectional view of the hot water supply tank; 2 is a sectional view taken along the line (A)-(A) in FIG. 1, FIG. 3 is a side sectional view showing an example of the heater, and FIG. 4 is an explanatory view of how it is assembled into an automobile.

The device consists of a tank body 1 and an outer cover 2, which is a sealed tank A with a double-walled structure similar to a thermos flask, and a hot water flow path installed through the bottom wall of the tank A. 3 and the cold water passage 4, and a water circulation port 5A that connects the outer ends of the tanks of the hot water flow passage 3 and the cold water passage 4, respectively.
15B and 5C, a water circulation path forming member 5 provided with a water circulation path, a heat exchange part 10 of a heater interposed in this water circulation port 5A, and a valve means 6 of the same type as a lightning provided in the water circulation port 5C. The main components are a washer liquid tank 31 as a cold water supply means and an attached liquid discharge pump 32, which are connected so as to be continuous with the water circulation ports 5B and 5C.

Both the tank body 1 and its outer cover 2 are made of stainless steel, and are molded into two parts, upper and lower, and then brazed in a vacuum furnace.
It has a circular, oval or cylindrical shape, and its water storage capacity is approximately 200 cc in this example. The gap between the tank body 1 and the outer cover 2 is maintained in a vacuum, giving the tank body 1 a heat-insulating performance similar to that of a thermos flask.

At the bottom of each of the tank body 1 and the outer cover 2,
The connection holes 1A and 2A for the hot water flow passage 3 are provided almost in the center, and the connection holes 1B and 2 for the cold water passage 4 are provided at the separated locations.
B is provided.

In this embodiment, the water circulation path forming member 5 is a block-shaped body made of synthetic resin with low thermal conductivity, and as shown in FIG. A water circulation path is formed by connecting a water circulation port 5A connected to the lower end, a water circulation port 5B connected to the outer end of the tank of the cold water passage 4, and a third water circulation port 5C connecting both circulation sections. There is. Of course, this water circulation path can also be created by connecting three pipes.

A flange-like rising portion 5E for connecting the lower end of the hot water flow path 3 is provided at the top of the water circulation path forming member 5. This rising portion 5E is screwed into the insertion hole 2A of the outer cover integral 2. They are fitted and fixed by bonding, gluing, or other methods. Under this assembled condition, the connection hole 2B of the cold water passage 4 is communicated with the upper end of the water circulation port 5B.

The hot water flow path 3 is a straight pipe made of stainless steel, and its lower end is connected to the water circulation path forming member 5 by a method such as fitting or adhesion.

The hot water flow path 3, which is thermally connected to the outside world by the protruding end portion from the bottom of the tank A, serves as a path for carrying out the retained heat of the hot water stored in the tank A to the outside world.
As shown in FIG. 1, a pipe-shaped central inner wall portion 11 (hereinafter abbreviated as a vacuum pipe) is attached as a hot water passage insulating means so as to surround the outer peripheral surface of the hot water flow passage 3.

The vacuum pipe 11 made of stainless steel has an inner diameter sufficient to allow the hot water flow path 3 to pass therethrough while maintaining sufficient space in its inner space, that is, a vacuum gap a. Its lower end is welded to the hot water flow path connection hole 1A of the tank body 1 to support the tank body 1. The upper end is narrowed down and fitted onto the hot water flow path 3, and the joint is airtightly sealed by welding, etc. As shown in the figure, the area around the hot water flow path 3 is covered with a double layer of tank A. ! ! It is surrounded by a vacuum gap a communicating with the vacuum region between.

The cold water passage 4 is a tube made of the same material as the hot water flow passage 3, and both ends thereof are joined to the connection holes 1B and 2B, respectively, and the intermediate portion between the two ends is shown in FIG. Thus, a passage extension 4A is formed in a loop along the outer periphery of the bottom double-wall space leading to the tank.

Water I! provided in the water circulation path forming member 5! 111g Ward 5A
A heat exchanging section 10 of a heater consisting of a combination of a heat exchanging section 10 and a heat generating section 20 is incorporated in the water circulation port 5A of the water circulation path consisting of connections of ~5C.

The heat exchange section 10 has a heat transfer area formed by giving a honeycomb shape or a corrugated shape to a corrosion-resistant metal cylindrical frame 10A having a cross-sectional shape similar to the cross-sectional shape of a water flow path, as shown in FIG. It is constructed by incorporating a group of increasing fins 108 and by welding fixing bolts 10C of the frame 10A to the outer peripheral surface.

The heat generating part 20 uses two plate-shaped positive temperature characteristic thermistors 22 manufactured so that the temperature at one point of Curie is approximately 80°C as a heat generation source, and these two thermistors are made of gold [1 It is housed in the case 25 so as to sandwich it therebetween. An electrode plate 23 is applied to the outer surface of the thermistor 22, and the electrode plate 23 is pressed against the outer surface as an electrode surface by a leaf spring 24. The heat exchanger plate 21 that maintains contact with the other electrode surface of the thermistor is connected to the heat exchanger 1
It is welded to the fixing bolt 10G of 0 and becomes a ground electrode. 2
6 is a lid portion of the case 25, and 27 and 28 are power supply lines.

A ball valve as a normally open valve means 6 is incorporated in the water circulation port 5C as shown in FIG. 6A
6B is a valve seat which opens toward the side leading to the water circulation port 5A and is shaped like a hollow well, and 6B is a ball serving as a valve body, which normally occupies the valve open position as shown in the figure.

A water supply tube 33 of an automobile windshield washer liquid injection system serving as a cold water supply means is connected to a connecting point 5D between the water circulation ports 5B and 5C.
When the valve is activated and water pressure is applied to the water+llll'I ring section 5C, the ball 6B is pressed against the valve seat 6A by the water pressure and the ball valve is closed.

A hot water extraction lower is provided in the water circulation path between the water circulation ports 5A and 5C.

In Fig. 4, B is the windshield, C is the wiper operating pole, D is the engine compartment, and E is the driver's instrument panel.
Tank A (not shown) is mounted by fixing the bracket part to the wall in the engine room using bolts. 50 is an in-vehicle battery power source; 51 is an engine key switch; 52 is a switch for energizing the thermistor 22, which can be turned on only when the engine key switch is turned on;
3 is a start switch for a liquid discharge pump 32 attached to the wiper operating pole B. 31 is a washer liquid tank, 32 is a liquid discharge pump, 33 is a water supply tube, and 34 and 35 are a heating washer liquid delivery hose and an injection nozzle.

Next, the operation of the above embodiment device will be explained. With the engine key switch 51 turned on, the switch 5
2 starts energizing the thermistor 22. The tank body 1 is filled with water supplied from the washer liquid tank 31 due to the operation of the liquid discharge pump 32 during the previous use of the device.

As the thermistor 22 generates heat, the cold water in the water circulation port 5A is rapidly heated and its specific gravity becomes lighter, and it rises in this pipe while displacing the cold water in the hot water flow path 3, so that the increased amount of hot water is A corresponding amount of cold water is pushed out from the tank body 1 through the cold water passage 4 at the bottom of the tank toward the water circulation path 5B → 5C → 5A by gravity and hot water upper surface pressure, and new cold water is replenished into the water circulation port 5A. be done. This make-up water is also heated and rises in the hot water flow path 3, so this water convection phenomenon continues until the water metal body in the tank body 1 reaches the maximum temperature that can be heated by the heater. .

In this embodiment, a positive temperature characteristic thermistor 22 whose Curie point is set at approximately 80°C is used, so when the water metal body in the tank body 1 is heated to approximately 80°C, the electrical resistance of the thermistor 22 increases significantly, and energization is virtually automatically stopped. Tank A, of course, does not have perfect heat shielding performance, so if the water temperature decreases over time, the thermistor 22, which maintains contact with the hot water, will also decrease in temperature and its electrical resistance will decrease accordingly. In other words, it behaves like an electric heater that also has a thermostat function.

Therefore, in winter, turn off the energizing switch 52 of the thermistor 22.
If it is left in the N state, the water in tank A will always be maintained at around 80°C while the car engine is running.

When the engine key switch 51 is turned off, the power to the narmistor 22 is also cut off, so that from then on, the heat retained in the heated water in the tank A is transferred to the hot water flow passage 3 and the cold water passage 4, which penetrate the tank wall and are in contact with the outside world. After that, it is gradually carried out of the tank.

In this case, the hot water carried away is the surface area of the hot water flow passage 3 and the cold water passage 4 that are in contact with the outside world, respectively;
It is approximately proportional to the temperature difference between the temperature of the hot water and the outside air temperature at this point of contact.

Therefore, the tank A of this embodiment, which is connected to the outside world only by two pipes, the hot water flow passage 3 and the cold water passage 4, which have a much narrower outer diameter than the water inlet of a household thermos flask, for example, is The area of the opening in contact with can be sufficiently narrowed.

In addition, the hot water flow path 3 has a vacuum vibrator 11 along its entire length.
Since only the top end opening directly touches the hot water, a temperature gradient occurs between this top end and the bottom end in contact with the outside world, and as the pipe approaches the bottom end of the hot water flow path 3, The temperature of the hot water inside the road is reduced, which has the effect of reducing the temperature difference with the outside air temperature. Based on this temperature gradient, heat is conducted from the upper end of the hot water flow path 3 toward the lower end, and the heat radiated from the pipe wall is transferred to the tank A.
returned inside.

On the other hand, the cold water passage 4 is provided with a passage extension 4A, and this extension 4A is also surrounded by a vacuum space. The effect of reducing the temperature difference between outside air and hot water can be achieved. That is, while passing through the cold water passage 4, the water is slightly warmed and enters the tank A.

Therefore, unlike household thermos flasks, the opening of tank 8 in this embodiment is not heat-shielded by a stopper, but is thermally connected to a water supply pipe or the like that has a considerable heat capacity. Nevertheless, the hot water in tank A can be kept warm for a long time.

The hot water in the thermos-type insulated tank that was heated while the vehicle was running the previous day or the day before the previous day as described above will be kept at 40°C the morning after driving, and above 20°C even the morning after the day after the next day, even in cold regions. It's dripping.

Therefore, in order to quickly remove frost or frozen snow from the windshield in the hurry before dispatch, first start the engine, energize the thermistor 22, and then use the washer built in the wiper operating rod B. When the start switch 53 of the liquid discharge pump 32 is turned on, the pump 32 starts operating and the normally open ball valve 6 is closed.

The washer fluid as cold water sent out from the tank 31 by the action of the pump 32 passes through the tube 33 and reaches the connection point 5D between the water circulation sections 5B and 50, but since the ball valve 6 is closed, it flows from the water circulation section 5C to 5A. The path leading to the cold water is cut off, and the cold water flows through the water circulation section 5B into the cold water passage 4 which penetrates the bottom of the tank A and communicates with the inside of the tank A.

Therefore, the pump 3 is used for hot water filling the tank body 1.
A discharge pressure of 2 is applied. Under this condition, the only opening through which hot water can be discharged to the outside of the tank is the upper end of the hot water flow passage 3 which opens close to the top inner wall surface of the tank body 1, and the lower end thereof. The section is water circulation area 5A.
It communicates with the atmosphere via → hot water extraction lower → washer fluid delivery hose 34 → injection nozzle 35. Since the injection nozzle 35 is installed at a higher position than the top of the tank body 1, the hot water stored in the tank A will not be discharged from the injection nozzle 35 due to its own weight.

As the cold water pumped out from the washer liquid tank 31 by the pump 32 is pushed into the tank body 1 through the cold water passage 4, an amount of hot water corresponding to the pushed amount flows into the upper end opening of the hot water flow passage 3. The hot water flows through the hot water flow path and is ejected from the injection nozzle 35 toward the frost surface of the windshield B.

The hot water in tank A, which had been heated during driving the previous day or two days before and had reached a maximum of nearly 80 degrees Celsius, was then turned off and the temperature dropped as mentioned above, but the water passed through water circulation area 5A. At this time, the temperature can be increased by at least 2° C. by the action of the thermistor 22.

Start of the washer liquid discharge pump 32! After defrosting is completed by operating the post-IJ wiper appropriately, the pump 32
When the start switch 53 is turned off, the supply of cold water to the tank body 1 is stopped, and at the same time, the ball valve 6, which has lost its opening force due to water pressure, is opened, so the device returns to a steady state. Returning, the heating action based on the natural convection phenomenon described above using the thermistor 22 as a heat supply source proceeds, and the water in the tank A is uniformly heated to around 80° C. within a relatively short time.

While the engine is running, the constant temperature maintenance function by the thermistor 22 continues to operate.

FIG. 5 shows a second embodiment of the device according to the present invention as a side sectional view. The difference from the first embodiment is that a sheathed heater 30 that receives power from a power line is used as a heater.

This embodiment of the device is suitable for use, for example, in a home where the hot water piping of a central hot water supply system is not sufficient for hand washing.

In that case, a pressurized water supply source such as a water supply serves as a cold water supply means, and a water stop valve such as a faucet provided in a water supply pipe serves as a valve closing means.

A thermostat (not shown) is connected to the current supply circuit to the sheathed heater 30 and closes the circuit when the water temperature in the tank Δ falls below a set temperature. Further, the heater may be anything that can heat the cold water introduced into the tank A, and may be an electric heater installed in the tank A. Alternatively, a cylindrical positive temperature characteristic thermistor may be housed within the vacuum gap a. Furthermore, even when convection heating is used, a valve such as a ball valve is not necessarily required.

FIG. 6 shows a side sectional view of a hot water supply tank as a third embodiment, which is characterized in that the flow direction of liquid can be controlled without using an on-off valve such as a ball valve.

In this embodiment, by narrowing the flow path cross-sectional area of the water circulation section 5C, when pressurized water is sent from the cold water supply means toward the cold water passage 4, this water circulation section 5C has a resistance against the pressurized water that is about to flow in. It works like this. Therefore, by appropriately selecting the flow path cross-sectional area, water circulation section 5
C produces a locking effect on inflow water only when pressurized water is supplied.

Figures 7 to 10 show tanks of fourth to seventh embodiments in which measures are taken to prevent the heat inside the tank from being dissipated to the outside world by radiation through the tank inner and outer walls. FIG.

In all of these embodiment tanks, a metal thin plate or a radiant heat shielding member is provided in the vacuum space a between the wall surface of the tank body 1 as the tank inner wall and the wall surface of the outer cover integral 2 as the tank outer wall. A metal 11111 material 40 is interposed in a suspended manner.

As for the suspension support method of the radiant heat shielding member 40, in any of the embodiments, the radiant heat shielding member 40 and the tank body 1 are
and at least one of the outer cover 2,
Permanent magnets 41A or 4 respectively under the opposing position M relationship
13 is attached, and by using the repulsive force of the same magnetic poles of these magnets, the radiant heat shielding member 40 is held at an intermediate position in the gap thickness direction within the vacuum gap a, and this member is attached to the tank A.
By touching the inner or outer wall of the tank A, the heat inside the tank A is prevented from being carried away by conduction to the outside world.

Radiant heat shielding member 4 used in the fourth embodiment shown in Fig. 7
0 has a bell shape large enough to completely cover the tank body 1, and a ring-shaped permanent magnet 41A is attached near the bottom end using an adhesive. Similarly, a ring-shaped permanent magnet 41B is adhered to the tank body 1 and the outer cover unit 2, respectively, in a positional relationship facing the magnet 41A, as shown in the figure.

Further, a small disc-shaped permanent magnet piece 41A is attached to the top of the bell-shaped radiant heat shielding member 40, and this magnet piece 4
A permanent magnet piece 41 of the same size is placed on the tank body 1 and the outer cover 2 while maintaining the positional relationship facing 1A.
3 is glued.

These three top magnet pieces serve to support the member 40 not only on the peripheral wall of the tank A but also on the top wall in a suspended state within the vacuum space a.

In the fifth embodiment shown in FIG. 8, a bell-shaped radiant heat shielding member 40
Two ring-shaped permanent magnets 41A are attached near the lower end of the magnet 41A with some distance between them. And outer cover 2
, the third ring-shaped permanent magnet 413 is positioned so that it fits in the middle of the gap between the two magnets.
In order to arrange the magnet 41B, a circumferential groove 2A for fitting the magnet 41B is provided. By utilizing the repulsive force between the same poles and the attractive force between the different poles of these three ring-shaped magnets, the radiant heat shielding member 40 is suspended and supported at the same position as in the fourth embodiment.

In the sixth embodiment shown in FIG. 9, the bottom portion 4 of the bell-shaped heat shielding member 40. The OA is bent inward in a seven-lung shape, and a permanent magnet 41A is attached to this bent surface, and a permanent magnet 41B is attached to the bottom surface of the outer cover unit 2 so as to face each other. This set of magnets is the radiant heat shielding member 4 at the top of tank A.
Participating in the suspended support of 0.

In the seventh embodiment shown in FIG. 10, a needle-like protrusion 42 is attached to the member 40 as shown in the figure in order to assist in suspending support at the top of the tank A.

The radiant heat shielding member 40 is arranged so that its wall thickness is as thin as possible without fear of being destroyed when it is assembled into the tank, and its thermal radiation rate is small. Suru.

It has been confirmed through a series of experiments that by incorporating these radiant heat shielding members 40, the loss due to heat radiation in the tank A can be reduced by about 0% compared to the case where this member is not provided.

In the above embodiment, a normally open type ball valve is used as the valve means of the water circulation path 5, but as another embodiment, a hemispherical check valve may be used as shown in FIG. 11. An eighth embodiment using this check valve will be described based on FIG. 11.

The water circulation sections 5F and 5G of the water circulation path 5 are connected to the passage extension section 4A described above, and the water supply tube 33 is connected to the water circulation section 5G. One of the water circulation sections 5I is connected to the connecting portion 5H between the water circulation sections 5F and 5G, and the water circulation section 5I is provided at an acute angle with the water circulation section 5G. The other side of the water circulation section 51 is provided with the valve means 6 of this embodiment.

The valve means 6 includes a valve means chamber 6C formed in the water circulation path forming member 5 and communicating with the water circulation section 5I and a communication path 7A provided on the heat exchange section 10 side of the hot water extraction lower, and a valve means chamber 6C formed in the water circulation path forming member 5. It is composed of a valve means forming member 6D and a valve body 6E provided inside the valve member 6C.

The valve means chamber 6C is connected to the water circulation section 5I and the communication passage 7 as described above.
A, and further communicates with the valve means forming member 6.
Together with D, it forms a valve chamber 6F.

The valve means forming member 6D has a valve chamber 6 in the upper part of the valve means chamber 6C.
It is a cylindrical member made lower than the height of the valve means chamber 6C in order to form the valve chamber F, and includes a hollow portion 6G that is open on the valve chamber 6F side. A communication passage 6H that communicates the water circulation section 51 and the hollow portion 6G is provided in the lower part of the valve means forming member 6D. Further, the upper opening of the valve means forming member 6D is formed in the shape of a wax ear that is lowered toward the hollow portion 6G in order to stably support the valve body 6F when water flows backward. .

The valve chamber 6F includes a hemispherical valve body 6 having a flange portion 6I.
F is stored. The valve body 6E is made of a resin having a specific gravity slightly greater than that of the fluid, and in this embodiment, it is made of a resin having a specific gravity slightly greater than that of water. This valve body 6F has a hollow hemispherical shape and is provided with seven tank portions 6I, so it can easily receive hot water when hot water flows backward, and the water circulation path forming member 5 and flange portion 6I are in contact with each other. As a result, movements other than opening/closing operations such as rotation within the valve chamber 6F can be prevented.

With the valve means 6 described above, this embodiment operates as follows.

When the thermistor 22 is energized when the cold water supply means is not operating, the heat exchange section 10 is heated.
The cold water in the communication path 7A is heated by this. Then, the water becomes hot water, its specific gravity becomes smaller, and it rises in the hot water flow path 3.

Due to the increased pressure of this hot water, the cold water in the tank body 1 is pushed out to the cold water passage 4, and passes through the passage extension 4A to the water circulation section 5F.
pushed out. Since this cold water supply means is not operating, it does not flow into the water circulation section 5G. The cold water in the water circulation section 5F is pushed out from the connection section 5 to the water circulation section 5I, and flows into the hollow section 6G of the valve means 6 through the communication path 6H. In this valve means 6, the cold water applies pressure to the valve body 6E and pushes the valve body 6E upward. The cold water that has passed through the valve body 6E is transferred to the heat exchange section 10.
The water is heated and becomes hot water, and the above cycle is repeated. The cold water in the tank body 1 is gradually heated and becomes hot water. When the hot water in the tank body 1 reaches a predetermined temperature, the thermistor 2
Power supply to 2 is stopped.

When the power supply to the mister 22 is stopped and the hot water in the tank body 1 is kept warm, the hot water in the communication path IA decreases as time passes. Then, the specific gravity of the hot water increases, and due to this increase in specific gravity, the hot water flows into the valve 6F.

However, since the opening of the valve means forming member 6D is closed by the valve element 6E, it is possible to prevent the hot water whose temperature has decreased and whose specific gravity has increased from flowing back. Therefore, convection within the tank body 1 during the heat retention state is eliminated, and the moisturizing effect of hot water is improved.

When the cold water supply means operates and cold water is supplied into the tank body 1, the cold water flowing into the water circulation section 5G is transferred to the connecting portion 5.
The water passes through H, is sent to the water circulation section 5F, and flows into the tank body 1 via the cold water passage 4.

The hot water in the tank body 1 is transferred from the hot water flow path 3 to the heat exchange section 1.
0 and is sent to the hot water extraction lower. At this time, at the fifth connection point, the cold water that has flowed into the water circulation section 5G exerts an ejector effect on the water circulation section 51, so that the cold water does not flow into the water circulation section 51.

As described above, according to this embodiment, it is possible to prevent the convection of hot water in the heat-retaining state, so that the heat-retaining effect can be improved.

[Effects of the invention] By taking heat insulation measures for the hot water flow passage and the cold water passage, which serve as heat transfer paths by thermally conducting the inside of the tank with a heat insulating structure and the outside world, these heat transfer paths Since the difference between the hot water in the heat transfer path and the outside air can be reduced at the point where the tank comes into contact with the outside air, this has the effect of sufficiently slowing down the speed at which the heat retained in the tank's hot water flows out to the outside world through heat transfer. .

Due to this effect, higher temperature water can be used during use, and the capacity of the tank can be reduced if necessary.

[Brief explanation of the drawing]

Figures 1 to 4 show a first embodiment of the tank used for defrosting the windshield of an automobile. (a)-(a) sectional view, Figure 3 is a side sectional view showing a specific example of the heat generating part of the heater used in the device in Figure 1, and Figure 11 is a side sectional view showing a specific example of the heat generating part of the heater used in the device in Figure 1. It is a typical explanatory view of the whole structure of a defroster. FIG. 5 is a longitudinal sectional view showing a tank according to a second embodiment of the present invention. FIG. 6 is a longitudinal sectional view showing a tank according to a third embodiment of the present invention. 7 to 10 are partial vertical sectional views of tanks according to fourth to seventh embodiments of the present invention, each of which is characterized in that a radiant heat shielding member is incorporated. FIG. 11 is a longitudinal sectional view of the eighth embodiment, which is characterized by the valve means of the water circulation path. In the diagram A... Tank 1... Tank body 2...
Integrated outer cover 3...Hot water flow passage 4...Cold water passage 4A-Passage extension 5A, 5815C...Water circulation section 6...Valve means 1...Hot water outlet 10.20
... Heater 11 ... Center inner wall (vacuum vibrator)
31... Washer liquid tank 32... Liquid discharge pump 31.32... Cold water supply means 40... Radiant heat shielding member 41A, 41B... Permanent magnet 53...
・Valve closing means (pump start switch) a...Vacuum gap

Claims (1)

[Scope of Claims] 1) (a) A tank having a double wall structure of an inner wall and an outer wall, and a vacuum layer formed between the inner wall and the outer wall; (b) installed through the bottom of the tank, one end of which is located near the top wall surface within the space surrounded by the inner wall;
(c) the other end part includes a hot water flow passage protruding outside the tank; (d) cold water mounted through the bottom of the inner wall and the bottom of the outer wall of the tank, with a passageway extension between the inner wall and the outer wall; A tank for supplying hot water, comprising: a passage; and (e) a heater for heating liquid in the tank. 2) The heater is provided outside the tank and heats the liquid within the inner wall of the tank by convection circulating in the hot water flow path and the cold water path. A hot water supply tank according to scope 1. 3) The hot water supply tank according to claim 1 or 2, characterized in that a radiant heat shielding member is interposed between the inner wall and the outer wall of the tank. 4) The hot water supply tank according to claim 3, wherein the radiant heat blocking member is a thin metal plate. 5) The radiant heat shielding member is suspended in the gap between the inner and outer walls by the repulsive force between the same poles of the member and permanent magnets attached to at least one of the inner wall and the outer wall. The hot water supply tank according to claim 3 or 4, characterized in that: 6) A check valve is provided in a water circulation path that communicates with the cold water passage and the hot water flow passage, and is opened by convection during heating by the heater and closed by reverse convection when heating is stopped. The second claim characterized in that
Tanks for hot water supply as described in section. 7) The hot water supply tank according to claim 6, characterized in that a radiant heat shielding member is interposed between the inner wall and the outer wall of the tank.