JP2002195653A - Electric water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To aggregate parts by adding a stop valve and a drain valve to an elbow provided at the bend of water supply piping being coupled with a hot water storage tank. SOLUTION: The electric water heater 1 comprises a hot water storage tank 2 arranged with an electric heater, water supply piping 3 coupled with the bottom section of the hot water storage tank 2, hot water supply piping 4 coupled with the upper section of the hot water storage tank 2, and a mixing valve 5 for mixing hot water from the hot water supply piping 4 with city water from the water supply piping 3 to regulate the temperature to a set level, wherein an elbow 10, having a stop valve and a drain valve for blocking backflow of hot water stored in the hot water storage tank 2 and draining the water supply piping 3, respectively, is provided at a bend in the water supply piping 3 in the vicinity of the hot water storage tank 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an electric water heater.

[0002]

2. Description of the Related Art Generally, as shown in FIG. 3, an electric water heater 1 includes a hot water storage tank 2 provided with an electric heater (not shown), a water supply pipe 3 connected to the bottom of the hot water storage tank 2, and
Mixing hot water supply pipe 4 connected to the upper part of hot water storage tank 2 with tap water from hot water supply pipe 4 and hot water from hot water supply pipe 4,
It is provided with a mixing valve 5 for adjusting the temperature to a set temperature. The tap water supplied to the hot water storage tank 2 is heated using inexpensive nighttime electric power, and the heated hot water is mixed via the hot water supply pipe 4. 5, the tap water is guided to the mixing valve 5 through the water supply pipe 3, and is adjusted to hot water at a set temperature to supply hot water to a kitchen or a bathroom.

[0003] An air intake valve 6 is provided at an upper portion of the hot water storage tank 2, and a drain plug 7 is provided at a lower portion thereof. The water supply pipe 3 is provided with a water stop valve 8.

[0004]

By the way, in the above-mentioned electric water heater 1, when maintenance and inspection and replacement of parts are performed, for example, when the mixing valve 5 is removed, the water stop valve 8 of the water supply pipe 3 is closed. Even if the supply of tap water is cut off, if hot water remains in the hot water storage tank 2, hot water having a water level higher than the mounting position of the mixing valve 5 will flow back through the water supply pipe 3 and overflow from the connection port of the mixing valve 5. Will be.

For this reason, when performing maintenance and inspections, the hot water in the hot water storage tank 2 must be drained, and power and water resources are wasted.
In the case of (1), there is a problem that it takes time to replenish drainage and tap water.

For this reason, a water stopcock for preventing backflow from the hot water storage tank 2 is provided in the water supply pipe 3 near the hot water storage tank 2, but the piping system becomes complicated, the number of parts increases, and the cost increases. It has the disadvantage of bulking.

The present invention has been made in view of such a problem, and a water stopcock and a drainage plug are added to an elbow provided at a bent portion of a water supply pipe connected to a hot water storage tank, so that parts of the component are added. An object of the present invention is to provide an electric water heater that can be centralized.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a hot water storage tank provided with an electric heater, a water supply pipe connected to the bottom of the hot water storage tank, a hot water supply pipe connected to the top of the hot water storage tank, and a hot water supply pipe. A mixing valve for mixing hot water and tap water from a water supply pipe and adjusting the temperature to a set temperature, in a bent portion of the water supply pipe near a hot water storage tank, the hot water stored in the hot water storage tank. It is characterized by providing a water stopcock and an elbow with a water drainage plug capable of preventing backflow and draining tap water in the water supply pipe.

According to the present invention, at the bent portion of the water supply pipe near the hot water storage tank, the backflow of the hot water stored in the hot water storage tank can be prevented and the tap water in the water supply pipe can be drained. By installing a stopcock and an elbow with a drain tap, the backstop of the stopcock and the elbow with the drain tap can be operated to ensure the backflow of hot water stored in the hot water storage tank during maintenance inspections and parts replacement. In addition, the water supply pipe can be drained by operating the water stopcock and the drainage plug of the elbow with the drainage plug as needed.

As a result, a water stopcock for preventing backflow of hot water stored in the hot water storage tank when maintenance and inspection and replacement of parts are performed, and a drain plug for the water supply pipe are connected to the elbow connecting the bent portion of the water supply pipe. Can be consolidated, the piping system can be simplified, and the number of parts can be reduced to reduce the cost. In addition, maintenance work and the like can be performed without draining the hot water stored in the hot water storage tank, and power resources and water resources can be effectively used without waste.

In the present invention, the elbow with a water stopcock and a water drainage plug has an L-shaped water supply passage having connection portions at both ends.
A receiving member mounting hole communicating with the water supply passage is formed at a position facing one connection portion, and a drain hole and a drain plug mounting hole communicating with the water supply passage are formed at a position facing the other connection portion. The formed elbow, a receiving member screw-coupled to the mounting hole for the receiving member of the elbow, and screwed to the receiving member,
A sealing member provided at the tip and capable of shutting off a water supply passage communicating with one of the connecting portions; and a drainage hole screwed into a mounting hole for a drain hole of an elbow, and a sealing member provided at the tip to drain the water. And a drain plug capable of opening and closing the hole.

[0012]

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

FIG. 1 shows an electric water heater 1 according to the present invention.

The electric water heater 1 has an elbow 10 with a water stopcock and a drain plug at a bent portion of the water supply pipe 3 near the hot water storage tank 2.

Here, the electric water heater 1 is the same as the electric water heater 1 shown in FIG. 3 except that an elbow 10 with a water stopcock and a drain plug is provided, and the same members are denoted by the same reference numerals. As shown in FIG. 2, a cast-iron elbow 11 with a water stopcock and a drain plug is omitted.
And a receiving member 12 fixed to the elbow 11, a water stopper 13 screwed to the receiving member 12, and a drain plug 14 screwed to the elbow 11.

The elbow 11 has connecting portions 11a, 11 at both ends.
b and L connecting these connecting portions 11a and 11b.
A water supply channel 11c is formed, and a receiving member mounting hole 11d communicating with the water supply channel 11c is formed at a position facing one connection portion 11b, and a water supply channel is formed at a position facing the other connection portion 11a. Drain hole 11d communicating with 11c
And a drain plug mounting hole 1 continuous with the drain hole 11d.
1f is formed. And the receiving member mounting hole 11
Female threads are formed in d and the drain hole mounting hole 11f, respectively. Further, the elbow 11 is provided with a sealing member 15A such as an O-ring located on the outer surface side of the receiving member mounting hole 11d, and at the position facing the receiving member mounting hole 11d, A valve seat 11x is formed on the outer peripheral edge. Further, the elbow 11 is formed with a valve seat 11y facing the drain hole 11e.

The receiving member 12 includes a flange portion 121 and a tubular portion 122. The flange portion 121 has an insertion hole 121a communicating with the tubular portion 122, and has an outer peripheral surface and an inner peripheral surface of the tubular portion 122. Has a male screw and a female screw, respectively. And the receiving member 12
A sealing member 15B such as an O-ring is disposed on the flange portion 121 facing the insertion hole 121a.

The male screw formed on the outer peripheral surface of the tubular portion 122 of the receiving member 12 can be screwed with the female screw formed in the receiving member mounting hole 11d of the elbow 11.

The water stop cock 13 has a water stop part 131 having a sealing member 15C such as a packing fixed at the tip thereof,
A threaded portion 132 formed with a male screw that can be screwed into a female screw formed on the inner peripheral surface of the tubular portion 122, an insertion portion 133 that can be inserted into an insertion hole 121a formed in the flange portion 121 of the receiving member 12, and In the outer surface of the insertion portion 133, an engagement groove 133a for rotating the water stopcock 13 is formed.

The water stop portion 131 of the water stop plug 13 and the sealing member 15C provided in the water stop portion 131 are larger than the outer diameter of the valve seat 11x formed in the water supply passage 11c of the elbow 11 described above. As described later, when the sealing member 15C of the water stopping portion 131 is seated on the valve seat 11x of the elbow 11 as described later, the water supply passage 11c communicated with the one connection portion 11b is cut off and the one connection portion is disconnected. Water can be prevented from flowing from the portion 11b to the other connection portion 11a through the water supply passage 11c.

The drain plug 14 includes a small-diameter portion 141 having a sealing member 15D such as a packing disposed at a tip thereof, and a small-diameter portion 1 having a small-diameter portion 1D.
A large-diameter portion 142 having an outer diameter larger than 41 and having an external thread formed on the outer peripheral surface thereof and capable of being screwed into a female screw formed in the drain hole mounting hole 11f of the elbow 11;
The length 42 is set so that a part thereof protrudes from the outer surface of the elbow 11. A water conduit 14a is formed from the large-diameter portion 142 to an intermediate position of the small-diameter portion 141, and the small-diameter portion 141 is formed with a plurality of radially extending water-guiding holes 141a communicating with the water-guiding channel 14a. I have.

The sealing member 15D provided on the small diameter portion 141 of the drain plug 14 is usually seated on the valve seat 11y facing the drain hole 11e formed in the elbow 11 described above. To prevent water from flowing through.

The elbow 10 with the water stopcock and the drain plug thus configured has a bent portion in the vicinity of the hot water storage tank 2 of the water supply pipe 3, and one connection portion 11 b of the elbow 10 is on the downstream side of the water supply pipe 3. On the second side, the other connecting portion 11 a is connected to the upstream side of the water supply pipe 3.

In the elbow 10 with the water stopcock and the drain plug, the sealing member 15D of the drain plug 14 is normally seated on the valve seat 11y facing the drain hole 11e of the elbow 11, and the drain hole 11e is formed. It is closed. Further, the sealing member 15C of the water stopcock 13 is separated from the valve seat 11x formed in the water supply passage 11c of the elbow 11, and the one connection portion 11b and the other connection portion 11a communicate with each other to form the water supply passage 11c. It is open.

Therefore, tap water can be supplied to the hot water storage tank 2 through the water supply pipe 3 and the elbow 10 with a water stopcock and a drain tap. The tap water supplied to the hot water storage tank 2 is boiled by an electric heater (not shown), and the boiled hot water is guided to the mixing valve 5 via the hot water supply pipe 4, and the tap water is mixed via the water supply pipe 3. It can be guided to the valve 5 and adjusted to hot water at a set temperature to supply hot water to a kitchen or a bathroom.

On the other hand, at the time of maintenance and inspection of the electric water heater 1 and replacement of parts, first, the water stop valve 8 of the water supply pipe 3 is closed, the air intake valve 6 is opened, and the hot water storage tank 2 is communicated with outside air. After that, the drain plug 7 is opened and the hot water storage tank 2 is opened.
A small amount of hot water stored in the hot water storage tank is drained, the outside air is introduced into the hot water storage tank 2 through an air suction valve, and the hot water storage tank 2 is depressurized. Then, after closing the drain plug 7, the engagement groove 133 a of the water stop cock and the water stop plug 13 of the elbow 10 with the drain plug is provided.
By inserting a flathead screwdriver or the like into the container and rotating it, the stopper 13 is advanced with respect to the receiving member 12,
The sealing member 15C of the water stopping portion 131 is seated on the valve seat 11x of the elbow 11. As a result, the water supply channel 11c communicating with the one connection portion 11b of the elbow 11 can be shut off. That is, it is possible to prevent the hot water stored in the hot water storage tank 2 from flowing backward through the water supply pipe 3 toward the mixing valve 5. Thereafter, various operations such as maintenance and inspection and parts replacement may be performed.

When the operation is completed, the water stopcock 13 of the elbow 10 with the water stopcock and the water drainage stop is rotated in the opposite direction to the above, so that the water stopcock 13 is retracted with respect to the receiving member 12. The sealing member 15 </ b> C of the water stopping portion 131 is attached to the valve seat 1 of the elbow 11.
1x, and the water supply channel 11c is opened. Then
After opening the water stop valve 8 of the water supply pipe 3 and supplying tap water to the hot water storage tank 2 through the water supply pipe 3 and the elbow 10 with a water stopcock and a drain tap, the air suction valve 6 may be closed.

When it is necessary to drain the water from the water supply pipe 3, the large-diameter portion 142 of the drain plug 14 of the elbow 10 with the stopcock and the drain plug is grasped and loosened with respect to the elbow 11. Then, the sealing member 15D of the drain plug 14 is connected to the elbow 1
1 is removed from the valve seat 11y facing the drain hole 11e, and the drain hole 11e of the elbow 11 is connected to the water guide hole 141 of the small diameter portion 141.
a and the drainage plug 14 communicates with the outside via the water conduit 14a. Therefore, the water in the water supply pipe 3 can be drained.

As described above, since the water supply pipe 3 constituting the electric water heater 1 is provided with the elbow 10 having the water stopcock and the water drainage plug at the bent portion near the hot water storage tank 2, the water supply pipe can be formed by a single component. 3 has a function of connecting the bent portion, a function of preventing backflow of hot water stored in the hot water storage tank 2 when performing maintenance and inspection, and replacement of parts, and a function of draining the water supply pipe 3. In addition, the piping system can be simplified, and the number of parts can be reduced to reduce the cost. Further, maintenance work and the like can be performed without draining the hot water from the hot water storage tank 2, and the power resources and the water resources can be effectively used without wasting them.

[0030]

As described above, according to the present invention, a water stop for preventing backflow of hot water stored in a hot water storage tank at the time of maintenance and inspection or replacement of parts is performed on an elbow connecting a bent portion of a water supply pipe. The plug and the drain plug of the water supply pipe can be integrated, so that the piping system can be simplified, and the number of parts can be reduced to reduce the cost. In addition, maintenance work and the like can be performed without draining the hot water stored in the hot water storage tank, and power resources and water resources can be effectively used without waste.

[Brief description of the drawings]

FIG. 1 is a schematic view of an electric water heater according to the present invention.

FIG. 2 is a cross-sectional view of a water faucet and an elbow with a drain cock provided in the electric water heater of the present invention.

FIG. 3 is a schematic view of a conventional electric water heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric water heater 2 Hot water storage tank 3 Water supply pipe 4 Hot water supply pipe 5 Mixing valve 10 Elbow with water stopcock and water drainage plug 11 Elbow 12 Receiving member 13 Water stopcock body 14 Water drainage plug body 15A, 15B, 15C, 15D Sealing member

Claims (2)

[Claims] 1. A hot water storage tank provided with an electric heater,
A water supply pipe connected to the bottom of the hot water storage tank, a hot water supply pipe connected to the top of the hot water storage tank, and a mixing valve for mixing hot water from the hot water supply pipe and tap water from the water supply pipe and adjusting the temperature to a set temperature. In the electric water heater provided, in the bent portion of the water supply pipe near the hot water storage tank, it is possible to prevent the backflow of the hot water stored in the hot water storage tank, and to drain the tap water in the water supply pipe. An electric water heater provided with a stopper and an elbow with a drain plug. 2. An elbow with a water stopcock and a water drainage stopper, wherein an L-shaped water supply passage having connection portions at both ends is formed,
A receiving member mounting hole communicating with the water supply passage is formed at a position facing one connection portion, and a drain hole and a drain plug mounting hole communicating with the water supply passage are formed at a position facing the other connection portion. The formed elbow, a receiving member screw-coupled to the mounting hole for the receiving member of the elbow, and screwed to the receiving member,
A sealing member provided at the tip and capable of shutting off a water supply passage communicating with one of the connecting portions; and a drainage hole screwed into a mounting hole for a drain hole of an elbow, and a sealing member provided at the tip to drain the water. 2. The electric water heater according to claim 1, further comprising a drain plug capable of opening and closing a hole.