JP3050878B2 - Indoor secondary circulation device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an indoor secondary circulation device. More specifically, the present invention relates to an indoor secondary circulation device including a hot water tank for storing hot water and a hot water distribution line having an outlet for selectively discharging hot water from the hot water tank.

(Prior art)

In the conventional indoor secondary circulation device 1 of this kind shown in FIG. 7, one end of a hot water distribution line 2 having one end sealed is connected to a hot water tank 3, and an outlet 4 provided in the hot water distribution line 2 is provided.
Was to supply hot water from.

[Problems to be solved by the invention]

In the conventional indoor secondary circulation device 1, since one end of the hot water distribution line 2 is sealed, when the outlet 4 is closed,
Warm water stayed in the warm water distribution line 2. for that reason,
When the outlet 4 is opened after a long period of time with the outlet 4 closed, first, the cooled water that stays in the hot water distribution line 2 and is cooled is discharged, so that hot water cannot be obtained immediately. . Therefore, there is a problem that the waiting time is long and the water discharged during that time is wasted.

In addition, since the cold water distribution line 5 is provided completely independently of the hot water distribution line 2, the hot water in the hot water distribution line 2 cannot be supplied to the cold water distribution line 5, and the cold water distribution line 5 cannot be supplied in winter. Water may freeze.

Therefore, a main object of the present invention is to provide an indoor secondary circulation device capable of supplying hot water immediately.

It is another object of the present invention to provide an indoor secondary circulation device that can prevent water in a cold water distribution line from freezing.

[Means for solving the problem]

The first invention is provided in a hot water tank for storing hot water, a hot water distribution line having an outlet for selectively discharging hot water in the hot water tank, a hot water circulation line for returning hot water in the hot water distribution line to the hot water tank, and a hot water circulation line. It has a hot water circulation pump, a tube that blows out hot water toward the bottom of the hot water tank, and a check valve that prevents backflow to the hot water circulation pump, and is attached to the top of the hot water tank and part of the hot water circulation line. Indoor 2 equipped with fittings constituting
Next circulation device.

The second invention is provided in a hot water tank for storing hot water, a hot water distribution line having an outlet for selectively discharging hot water in the hot water tank, a hot water circulation line for returning hot water in the hot water distribution line to the hot water tank, and a hot water circulation line. A hot water circulation pump, a cold water main pipe, a cold water distribution line having an outlet for selectively discharging cold water from the cold water main pipe, a cold water circulation line for returning cold water from the cold water distribution line to the cold water distribution line, and a cold water circulation line are provided. This is an indoor secondary circulation device that includes a cold water circulation pump and allows a part of the hot water from the hot water distribution line to flow to the cold water distribution line as needed.

[Action and effect]

A hot water circulation line for returning hot water in the hot water distribution line to the hot water tank is provided, and the hot water in the hot water distribution line is circulated by a hot water circulation pump. Therefore, the temperature of the hot water in the hot water distribution line can always be kept constant,
Hot water of a certain temperature can be supplied immediately from an outlet provided in the hot water distribution line.

In another aspect of the present invention, a cold water distribution line is provided separately from the hot water distribution line, and a portion of the hot water from the hot water distribution line flows to the cold water distribution line as appropriate. Therefore, freezing of water in the cold water distribution line can be prevented.

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

〔Example〕

The indoor secondary circulation device of this embodiment shown in FIG. 1 includes a circulation pump 2 and a T fitting 5. Circulation pump 2
Is composed of a pump motor 1 and a pump housing having an impeller 3. The circulating pump 2 is connected by a tube 4 to a vertical tube 5 a of a T-fitting 5. The T fitting 5 has, at its upper end, an opening 6 which is threaded to connect one end of a hot water distribution pipe 6b constituting a hot water distribution line 6a. T
At the opening at the lower end of the fitting 5, a union 7 is provided, which is screwed to the outlet nipple 9 of the hot water tank 10. The end of the hot water distribution line 6a, that is, the other end of the hot water distribution pipe 6b, is connected to one end of a circulation tube 12 constituting a circulation line, and the other end of the circulation tube 12 is connected to the suction side of the circulation pump 2. Circulation tube
Numeral 12 is made of plastic, copper, or the like, and has a considerably smaller diameter than the hot water distribution pipe 6b.

Tube 4 preferably made of stainless steel
Is brazed to the outlet opening 20 of the circulation pump 2. The tube 4 is connected to a tube 23 arranged in the vertical tube 5a of the T fitting 5. Ring 25 is tube 4
And has an eccentric hole 26. Tube 4
Contains a valve ball 27, the diameter of which is somewhat larger than the diameter of the hole 26. Tube 4 also includes a horizontal septum 28 that limits movement of ball 27. Compared to check valves, this ball allows water to flow without pressure drop,
Evacuating air from circulation tube 12 through tube 4,
It acts as a check valve for the flow of water on the opposite side to the direction conveyed by the circulation pump 2.

Thermostat switch 30 arranged in circulation pump 2
Turns off the circulation pump 2 as soon as the temperature of the water entering via the circulation tube 12 reaches a certain value, and the temperature difference of the water in the circulation pump 2 is less than the optimum hot water temperature by about 15 ° F. As soon as it drops, the circulation pump 2 is turned on again.
The fins 8, preferably made of copper metal sheet, take the heat from the tube 4, so that the circulation pump 2 is cooled if it is not running.

As long as the circulation pump 2 is running, the impeller 3 generates pressure in the pump housing. The suction force is applied to the circulation tube 12. Discharge takes place through the hole 26 and the tubes 4 and 23, and thus the cooled circulation 24
Is ejected downward into the tank 10 and returned to the bottom of the tank 10. In this method, it is not necessary to provide a return opening in the tank 10.

When the thermostat switch 30 turns off the circulation pump 2, the circulation stops, and the hot water distribution pipe 6b and the pump housing cool. Hot water is 15 ゜ F above the original hot water temperature
The cycle starts again as soon as it is cooled below.
The tube 4 is made of thin stainless steel having a thermal conductivity that is at least 10 times smaller than that of a brass tube. Thus, minimal heat is transferred by the tube 4 from the warm water flowing through the T-fitting 5. Tube 4 may be formed of any other metal. The septum 28 inhibits heat convection in the tube 4, so that the trapped immobile water does not conduct heat and the remaining low heat flux through the metal wall of the tube 4 is dissipated through the heat exchange fins 8.

When several taps or taps 6c are opened at the same time, the backflow pushes the valve ball 27 into the hole 26, thus preventing water from flowing into the pump housing in a direction opposite to that by the circulating pump 2.

Since the system in FIG. 1 is initially filled with water, the outlet located farthest from the tank 10
6d must be opened slightly so that the air in tube 12 can escape and fill tube 12 with water. During this initial air removal, the holes 26 remain open, thus allowing the tube 12 to be filled. For this reason, the eccentric hole 26 is located at a sufficiently high position, and therefore rises only when the valve ball 27 is at a high average valve passage speed of water, and is fixed in the position shown to allow filling of the tube 12 at low speeds. Stay in.

According to this embodiment, the circulation tube 12, the circulation pump 2, T
Since hot water is circulated to the hot water distribution line 6a through the fitting 5 and the hot water tank 10, hot water at a constant temperature always flows through the hot water distribution line 6a. Therefore, there is no fear that the hot water is cooled in the hot water distribution line 6a, and the hot water can be obtained as soon as the plug 6c is opened.

Further, the hot water returned to the hot water tank 10 is cooled and becomes heavy in the process of passing through the hot water distribution line and the circulation line, and is jetted downward from the lower end of the tube 23. Through the warm water layer and returned to the bottom. Therefore, the return water can be sufficiently heated by the heating device.

In addition, since the circulation tube 12 is initially filled with water, the air is not filled with a high flow rate,
ng device) ensures that the air in the circulating tube 12 is properly expelled. This watering device can reduce the cross section of the circulation tube 12 to about 10% of that of the hot water distribution pipe 6b. Therefore, a copper or plastic tube which is thin and can be bent by hand can be used, and can be connected in parallel to the hot water distribution pipe 6b. Due to its very small diameter, such tubes can also be installed in the same thermal barrier.

In the indoor secondary circulation device of another embodiment shown in FIG.
A fitting 31 as shown in FIGS. 2A and 2B is used. The fitting 31 includes a main body 31a and a dip tube. The dip tube 34 is disposed so as to pass vertically through the entire hot water tank 10, and the dip tube 23
Is connected via a union 37 to the lower end of the main body 31a. The two arms 31a and 31b of the fitting 31 hold two circulation pumps 32 and 33. The hot water circulation pump 32 having the motor 38 and the timer 40 circulates water into the hot water distribution pipe 53 forming the hot water distribution line 53a through the circulation tube 41 forming the circulation line. The chilled water circulation pump 33 having the motor 39 circulates chilled water into the chilled water distribution pipe 56 forming the chilled water distribution line 56a through the circulation tube 42 forming the circulation line. Hot water circulation pump 32
Equipped with a thermostat switch 43 and a chilled water circulation pump 33
Has a thermostat switch 45 having a timer 44 and a sensor 46.

FIG. 2B is a side view of the fitting 31 without the pump. If several taps or taps are opened at the same time, a significant pressure drop will occur in the water pipe and the valve ball 47 held in the position shown below the hole 49 by the wire strap 48 will be pushed into the hole 49. . Cooling water main pipe 55 (Fig. 3) is fitting 31
Cool water through the nipple 50 of the system. Second
Nipple 51 is connected to a cold water distribution pipe 56 (FIG. 3). When a predetermined water temperature is reached (for example, 150 ° F.), the thermostat switch 43 incorporated in the hot water circulation pump 32 shuts off the hot water circulation pump 32 as described in FIG. To save energy due to heat loss, a 24-hour timer 40 prevents hot water circulation at night.

Timer 44 turns on cold water circulation pump 33 for several minutes every hour,
Prevent ice formation in the system. When the temperature of the chilled water stream falls below a predetermined value slightly higher than the solidification temperature (eg, 37 ° F.), the sensor 46 of the chilled water circulation pump 33 closes a switch 45 disposed on the pump housing. The thermostat switch 43 operates the chilled water circulation pump 33 as long as the water temperature is higher than the solidification temperature but below a predetermined temperature close to the temperature, and the contents of the pipe are required to make a round of the chilled water circuit through the chilled water circulation pump 33. The operation is repeated such that the chilled water circulation pump 33 is turned on for a longer time and the chilled water circulation pump 33 is turned off for a shorter time required for the entire cross section of the chilled water distribution line 56a to be closed by the accumulation of ice. Therefore, freezing of water in the cold water distribution line 56a is efficiently suppressed.

FIG. 3 is a flow diagram of a system in a house. The contents of the tank 10 are heated by the heating device 52. Hot water flows to outlet 54 through hot water distribution pipe 53.
The circulation tube 41 is connected to the suction side of the hot water circulation pump 32. When the hot water circulation pump 32 sucks the hot water in the tank 10 through the hot water distribution pipe 53, the same amount of cold water is conveyed to the bottom area of the tank 10 through the dip tube 62 of the fitting 31. The cold water distribution pipe 56 is also connected to the nipple 51 (No.
2B) is connected to fitting 31 via
And lead to 58. The ends of the pipes 55, 56 and 59 are connected to the ends of the circulation tubes 42, 42a and 42b, and return the circulated water flow to the suction side of the cold water circulation pump 33. As long as the chilled water circulation pump 33 is operating, the contents of the pipes 55, 56 and 59 are circulated. This water does not enter the tank 10. If, on the other hand, the two pumps 32 and 33 are operating at the same time, a portion of the chilled water circulating flow mixes with the circulating chilled water from the chilled water circulating pump 33 into the water in pipes 55, 56 and 59. I do.

The function of the two pumps 32 and 33 will be explained with reference to the circuit diagrams in FIGS. 4, 5 and 6.

FIG. 4 shows an electric circuit diagram. A first conductor 60a of the power supply is connected to one lead of the pumps 32 and 33, the cyclic timer 44 and the 24-hour timer 40. Second conductor 40b
Are connected to the other leads of the cyclic timers 40 and 44, the thermostat switch 45 and the double throw switch 61. This switch 61 is the second motor of the chilled water circulation pump 33.
Or the switch 40a of the timer 40 which leads the second lead of the motor of the hot water circulation pump 32. When the thermostat switch 43 reaches a preset temperature, the operation of the motor of the hot water circulation pump 32 is stopped.

When the hot water circulation is set to be discontinuous within a certain period of the day, the switch 40a turns off the motor of the hot water circulation pump 32 by the 24-hour timer 40. In this position, the double throw switch 61 of the cyclic timer 44 supplies power only to the hot water circulation pump 32.

In FIG. 5, the double throw switch 61 is connected to the hot water circulation pump 32.
Is turned off, and the cold water circulation pump 33 is activated for 1 to 3 minutes. This time interval depends on the length and diameter of the cold water distribution pipe 56 and the circulation tube 42 (see FIG. 3). The water in the pipe must be circulated at least once.

FIG. 6 shows the system in thaw mode. When the water temperature of the system drops significantly below the ambient temperature of the building, a sensor 46 turns on switch 45, indicating that ice is beginning to form somewhere in the pipe. Switch 45 controls all other switches and creates circulation in both the cold and hot water circuits. At this stage, both the circulating cold water provided by the chilled water circulation pump 33 and a portion of the warm water provided by the hot water circulation pump 32 flow through the nipple 51 (FIG. 3) into the chilled water circuit. Such a mixture of cold and hot water will melt any ice formed in the cold water system. As the ice melts, the water temperature increases and sensor 46 returns the circuit to one of the modes in FIG. 4 or FIG.

According to this embodiment, since hot water is circulated in the hot water distribution line 53a, hot water can be obtained immediately when the stopper 54 is opened.

In the deicing mode, the circulating cold water provided by the chilled water circulating pump 33 and a portion of the warm water provided by the hot water circulating pump 32 are caused to flow through the chilled water circuit, so that the chilled water circuit can be prevented from freezing.

Further, since the cold water is conveyed to the bottom of the tank 10 through the fitting 31, the cold water can be sufficiently heated by the heating device 52.

[Brief description of the drawings]

FIG. 1 shows a T-fitting provided on the upper part of the tank and a circulating pump attached thereto. FIG. 2 shows a unit comprising a hot water circulation pump for hot water circulation and a cold water circulation pump for cold water circulation to be fixed on a dip tube. FIG. 3 schematically shows a pipe system for the pump shown in FIG. FIG. 4 shows the electrical circuit of the pump shown in FIG. 2 for an off period, such as at night. FIG. 5 shows the same circuit during a short period of cold water circulation to test the water temperature. FIG. 6 shows the same circuit during which the collected ice is melted. FIG. 7 shows a conventional indoor secondary circulation device. In the figure, 2, 32, 33 are pumps, 5 is T fitting, 31 is fitting, 10 is hot water tank, 12, 41, 42 are circulation tubes, and 23 is a tube.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Johannes N. Lang 3970, Honeycut Street, Sanjego, California, USA (56) References JP-A-60-240936 (JP, A) (Int.Cl. ⁷ , DB name) F24D 3/00

Claims (4)

(57) [Claims] A hot water tank for storing hot water; a hot water distribution line having an outlet for selectively discharging hot water from the hot water tank; a hot water circulation line for returning hot water in the hot water distribution line to the hot water tank; A hot water circulation pump, and a tube that blows out the hot water toward the bottom of the hot water tank, and a check valve that prevents backflow to the hot water circulation pump, and is attached to an upper portion of the hot water tank. An indoor secondary circulation device, comprising: a fitting that forms a part of the hot water circulation line. 2. A hot water tank for storing hot water, a hot water distribution line having an outlet for selectively discharging hot water from the hot water tank, a hot water circulation line for returning hot water in the hot water distribution line to the hot water tank, and a hot water circulation line. A hot water circulation pump provided in the chilled water main pipe; a chilled water distribution line having an outlet for selectively discharging chilled water from the chilled water main pipe; a chilled water circulation line returning chilled water from the chilled water distribution line to the chilled water distribution line; An indoor secondary circulation device, comprising: a cold water circulation pump provided in the cold water circulation line, wherein a part of the hot water from the hot water distribution line flows to the cold water distribution line as needed. 3. A first opening connected to an outlet of the hot water circulation pump, a second opening connected to an outlet of the cold water circulation pump, and a hot water in the hot water distribution line at a bottom of the hot water tank. 3. The indoor secondary circulation device according to claim 2, wherein a fitting including a tube for returning to the hot water tank is attached to an upper portion of the hot water tank. 4. A thermostat switch, wherein the thermostat switch turns on the chilled water circulation pump for a time longer than the time required for water in the pipe to make a round of the chilled water circuit, and further comprises a thermostat switch. 4. The indoor secondary circulation device according to claim 2, wherein the operation of turning off the chilled water circulation pump is repeated for a time shorter than a time required for the cross section to be closed by the accumulation of ice.