JPH0665329B2 - Electric water heater - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to air for sealing an opening of a water container, forcing air into the water container by an air pump, and discharging hot water in the water container to the outside through a pumping pipe. Type electric water heater.

Conventional structure and its problems Generally, the seal of this kind of electric water heater is made of silicone rubber because it is required to have heat resistance, steam deterioration resistance and odorlessness. However, even if it has the best performance at the current industrial level, if it is used for more than 12 hours a day, the sealing property will be lost and the function will be lost in 6 to 12 months, which is uneconomical. There is.

Fluorine rubber exists as a measure against the deterioration of the sealing property due to the deterioration of the rubber property (hydrolysis) due to the steam, but in this case, in particular, permanent deformation occurs in an extremely short time, and a drawback of sticking to a metal water container, and further About 2 of high-grade silicone rubber
It was difficult to put into practical use because the cost was twice as high.

OBJECT OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks, and an object of the present invention is to provide an electric water heater with a seal structure having extremely high durability.

In order to achieve the above object, the present invention provides a water container in the main body, and has a pump mechanism for pumping air into the water container to discharge hot water in the water container to the outside through a pumping pipe, A spout having a hanging wall is provided on the outer circumference of the upper end flange of the water container, and an air supply hole and a pumping pipe are provided at a substantially central portion. A ring-shaped heat-resistant rubber seal packing in which a dog-legged mounting portion and a substantially J-shaped seal portion are integrally connected is provided, and the seal portion of this seal packing is provided between the water container flange and the outer peripheral rib of the seal lid. The pressure is applied to seal the air that is pumped into the water container.

Description of Embodiments Embodiments of the present invention will be specifically described below with reference to the accompanying drawings. FIGS. 1 to 4 show a first embodiment, and 1 is a water container, which is a bottomed cylindrical shape with a flange 1a formed on the upper end and is made of stainless steel. Reference numeral 2 is a cylindrical body, and a spout 3 is placed on the upper end thereof. The spout 3 has a hanging wall 3a and a locking step
3b is provided, and the flange 1a of the water container 1 is engaged with the locking step portion 3b via the waterproof rubber 4. A fitting 1c is fixed to the bottom of the water container 1, and a base 5 and a back plate 6 located at the lower end of the body 2 are screwed together to form a main body 1 '.

Reference numeral 7 denotes a substantially dish-shaped seal lid, which is made of a synthetic resin such as polypropylene having good heat resistance and steam deterioration resistance and low vapor permeability, and has an air supply hole 8 in the central portion, an outer edge wall 9, an outer peripheral rib 10 and a guide. A water pipe 11 is provided. A pumping pipe 13 is attached to one of the water guiding pipes 11 via a fall valve 12, and a discharge port 14 is attached to the other, forming a pumping passage 15 for discharging the liquid in the water container 1 to the outside. .

Reference numeral 16 is a seal packing, which is made of flexible silicone rubber having good heat resistance, steam deterioration resistance, permanent set resistance, and flexibility, and an attaching portion 17 having a V-shaped cross section and a substantially J-shaped sealing portion 18 are integrated. The attachment portion 17 is stretched outside the outer edge wall 9 of the seal lid 7.

Reference numeral 19 denotes an upper lid which opens and closes the upper opening of the spout 3, one end of which is detachably hinged to the spout 3 by a shaft 20 and the other end of which is hooked to the spout 3 by a hook 21 so as to be openable and closable. There is.

Reference numeral 22 denotes a pump mechanism for sending air under pressure, which includes a bellows 22a, a check valve 22b, a pressing plate 22c, a pump base plate 22d, and a connecting packing 22e.
The seal packing 7 is connected to the air supply hole 8 of the seal lid 7 to send air under pressure into the water container 1.

23 is a handle, 24 is an electric heater, 25 and 26 are temperature controllers, 27 is a connection plug, 28 is a water level gauge, 29 is a lamp for displaying electricity, 30 is a safety fuse, and 31 is a gauge window.

Next, the operation of sealing the inside of the water container 1 with the seal lid 7 and the seal packing 16 in the above configuration will be described.

As shown in FIG. 4, when the seal lid 7 is put into the spout 3,
The bottom surface of the seal portion 18 of the seal packing 16 contacts the upper portion of the flange 1a of the water container 1. Next, when the upper lid 19 is closed, the convex rib 22f provided on the lower surface of the pump base 22d presses the seal lid 7 downward. When the upper lid 7 is engaged with the spout 3 by the hook 21, the mounting portion 17 and the sealing portion 18 of the seal packing 16 are deformed by being pressed between the flange 1a and the outer peripheral rib 10 of the seal lid 7 as shown in FIG. Then, the flange 1a and the outer edge wall 9 of the seal lid 7 and the outer peripheral rib 10 are tightly sealed.

As a result, when the pump mechanism 22 is actuated, air is pumped into the water container 1 to be pressurized, and the hot water inside is discharged through the pumping passage 15 to the outside of the main body.

Since the water in the water container 1 is constantly heated to about 95 ° C. by the action of the electric heater 24 and the temperature controllers 25 and 26, the seal packing 16 is exposed to steam.
However, since the seal portion 18 of the seal packing 16 is composed of the planar lowermost end with the tip end removed, hydrolysis deterioration is less likely to occur, and the life of the seal packing 16 can be greatly improved. Further, since the lowermost end of the doglegged mounting portion 17 is in contact with or in the vicinity of the corner of the flange 1a of the water container 1, steam only hits this mounting portion 17 and is prevented from entering the seal portion 18. It will be.

Further, the temperature of the seal portion 18 is also insulated by the mounting portion 17, so that the temperature can be lowered. For example, if the temperature of the hot water in the water container 1 is set to 95 ° C, the seal portion 18 can be maintained at about 80 to 85 ° C.

With the above operation, the seal portion of the seal packing 16 is approximately J
By making it into a letter shape, even if the tip portion, which is most susceptible to hydrolysis deterioration, deteriorates, sealing is possible and high durability can be secured. In addition, the V-shaped mounting part of the seal packing 16
Even if pre-sealing is performed at 17, the durability of the seal portion 18 can be made extremely long because steam does not directly hit it. In particular, silicone rubber is most effective since it has the weakest property of being hydrolyzed and deteriorated by hot steam. Since this hydrolysis gradually deteriorates and permeates from the surface layer,
The destruction of the seal packing 16 in the sealing property is the time until the surface of the mounting portion 17 is deteriorated, steam invades the seal portion 18, and the seal portion 18 is further deteriorated. It was confirmed that the product had durability.

Further, as described above, the hydrolysis progresses sequentially from the surface, so the deterioration time can be lengthened in proportion to the thickness.
In the shape of the seal packing 16 described above, an L-shaped mounting portion
Since the deformation amount of 17 can be made extremely small, the thickness of 2 to 4 mm is made thick, and the load pressing the seal lid 7 can be made light even if the thickness of the seal portion having a large amount of deformation is made thin to about 0.8 to 1.5 mm. . Also in this respect, the durability time can be extended. Further, since the bottom surface of the seal portion 18 of the seal packing 16 comes into close contact with the flange 1a when pressure is applied, the reliability of the seal is greatly improved.

FIG. 5 shows a third embodiment of the present invention.

Reference numeral 32 denotes a stainless steel plate or a polysulfone resin back cover having extremely low heat resistance and vapor permeability, and is formed in a substantially dish shape so as to cover the inner diameter portion from the outer edge wall 9 of the seal lid 7.
The body portion 32a and the outer edge wall 9 are in close contact with each other or in close proximity to each other, and are attached to the mounting legs 7a provided on the seal lid 7 with screws 33. Further, a vent hole 32b communicating with the air supply hole 8 provided in the seal lid 7 is provided in the bottom portion, and a through hole (not shown) for penetrating the pumping pipe 13 is provided in the substantially central portion. Steam stop flange 32c facing the outer peripheral rib 10 of
Is provided. The outer diameter of the body portion 32a is dimensioned to form a small gap (about 0.2 to 1 mm) with the inner wall of the water container 1, and the outer diameter of the steam stop flange 32c is 0.5 to 7 mm with the flange 1a of the water container 1. It is dimensioned with some overlap margin. Further, the distance between the lower surface of the outer peripheral rib 10 of the seal lid 7 and the upper surface of the steam stop flange 32c is determined by the seal packing 16
It is formed to have a height substantially equal to that of the mounting portion 17.

As in the case of the second embodiment, when the sealing lid 7 is set in the inlet 3 and the upper lid 19 is closed, the sealing lid 7 becomes the pump base 22d.
The convex rib 22f presses the steam stop flange 32c of the back cover 32 into contact with or very close to the flange 1a. At the same time, the seal portion 18 of the seal packing 16 is deformed by pressing and is pressed against the flange 1a, the outer peripheral rib 10 and the vertical wall 3a to perform a sealing action.

As a result, the water vapor in the water container 1 penetrates in the direction of the seal packing 16 through the small gap between the side wall of the water container 1 and the body portion 32a of the back cover 32, but the gap is small and Since the temperature of the portion is lower than the ambient temperature in the water container 1, the water droplets B are successively condensed in the gaps and the water droplets B are accumulated to block the vapor passage.

On the other hand, even if this passage is not closed, the flange 1a and the steam stop flange 32c are in contact with or in close proximity to each other, so that steam can be blocked also in this portion by the same action as described above.

Further, since the steam passing through the ventilation hole 32b is in close contact or extremely close to the body portion 32a and the outer edge wall 9, the steam passage is also closed in this portion by the condensed water as described above.

With the above action, the seal portion 18 of the seal packing 16 is hardly exposed to steam, and the temperature can be lowered, so that hydrolysis and permanent deformation due to steam are extremely small, and the durability can be greatly improved. It is a thing.
The hydrolysis rate of silicone rubber is slower in hot water under atmospheric pressure than in steam, and there is little concern about deterioration due to dew condensation.

It should be noted that replacement and repair of the seal packing is extremely simple in any of the embodiments of the present invention. Further, in the present embodiment, the seal lid 7 and the upper lid 19 are described as separate bodies, but it goes without saying that the same effect can be obtained even if they are integrated.

EFFECTS OF THE INVENTION As is clear from the above description of each embodiment, according to the present invention, (a) the seal portion is not the tip portion that is vulnerable to hydrolysis deterioration due to heat and steam, but the surface portion of the J-shaped bottom end. Therefore, the durability is significantly improved.

(B) Since the seal part is J-shaped, it is difficult for condensed water to drip onto the floor when the seal lid is opened.

(C) Even with a light seal lid operation, the sealing property of the seal portion becomes reliable when pressure is applied, and the practical effect is high.

(D) The seal durability of the seal packing is low and the steam does not come into direct contact with the seal packing, so that the seal packing can be made extremely long-term. In particular, silicone rubber has the most weak property against hydrolysis and deterioration due to hot steam, so that its effect is remarkable. (Claims 2 and 3) and so on, and their industrial value is extremely large.

[Brief description of drawings]

FIG. 1 is an overall cross-sectional view of an electric water heater showing the first and second embodiments of the present invention, FIG. 2 is a cross-sectional view of the same main portion, and FIG. 3 is a cross-sectional view of seal packing of the same main portion. FIG. 4 is a sectional view for explaining the operation of the main part, and FIG. 5 is a sectional view of the main part in the third embodiment of the present invention. 1 ... water container, 1a ... flange, 3 ... spout, 3a ... vertical wall, 7 ... seal lid, 8 ... air supply hole, 9 ... outer wall, 10
...... Outer peripheral ribs, 16 …… Seal packing, 17 …… dog-legged mounting section, 18 …… Seal section, 22 …… Pump mechanism.

Claims (2)

[Claims] 1. A spout having a hanging wall for supporting an upper end flange portion of a water container in the main body, and a seal lid for covering the water container,
The seal lid has an outer peripheral rib on an outer peripheral portion and a seal packing holding portion provided with an outer edge wall vertically extending from the outer peripheral rib, and the seal packing holding portion includes a substantially V-shaped mounting portion in contact with the outer peripheral rib and the outer edge wall. A ring-shaped heat-resistant rubber seal packing, in which substantially J-shaped seal parts are integrally connected, is provided. When the seal lid is set, the tip of the J-shaped seal part of the seal packing is located inside and above the water container flange part. Electric water heater with a configuration. 2. The electric water heater according to claim 1, wherein the lowermost end of the substantially V-shaped mounting portion is arranged so as to be close to or in close contact with the upper end flange portion of the water container.