JPH0345642B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an electric water heater with an improved hot water pouring method.

Conventional technology Conventional electric water heaters of this type generally used a bellows pump driven by a motor or the like to force air into a container and pour out hot water from the container. .

Problems to be Solved by the Invention However, conventional electric water heaters discharge the liquid by sending air into the container and pressurizing the air inside the container. In the case of hot water, the pressure inside the container becomes abnormally high due to the vapor pressure of the hot water, and even if a small amount of air is pumped, a larger amount of hot water than expected is discharged. On the other hand, if the amount of hot water remaining in the container decreases, air and hot water will come out of the outlet in a mixed state, causing the hot water to scatter and cause burns. in this way,
The conventional method of blowing air into a container and discharging hot water indirectly had problems.

The present invention solves these problems,
The purpose of the present invention is to provide a water heater that directly discharges hot water using a centrifugal pump.

Means for Solving the Problems In order to solve the above problems, the present invention provides an impeller driven by a motor, and a gap of approximately constant width continuously provided on a concentric circle along the outer periphery of the impeller. A centrifugal pump consisting of a pump chamber is installed at the bottom of a container for storing hot water, and the hot water in the container is poured from a water inlet.

Function Centrifugal pumps are generally known, but it was believed that they could not be used to pump water that is boiling or has just boiled. This is because the higher the temperature of the hot water, the more air enters the hot water, and this air enters the pump chamber of the centrifugal pump, causing the impeller to rotate idly within the pump chamber. In particular, the volume of the pump chamber of a general centrifugal pump increases in a spiral manner in order to increase pump efficiency, making it easy for air bubbles to occur due to depressurization. The above-mentioned impeller is likely to idle.

However, according to the present invention, by using a centrifugal pump in which the pump chamber is provided with a gap of approximately constant width continuously on a concentric circle along the outer periphery of the impeller, even when the impeller is rotated at high speed. ,
The volume of the pump chamber is small, and the discharge flow rate is suppressed by the effect of the gap. In other words, this pump pushes out the liquid rather than sucking it in through the rotation of the impeller, so the amount of air sucked into the pump chamber is small, and the growth of air is suppressed, so even if it grows, the amount of hot water will not exceed the capacity of the container. Since the amount is limited, it is sufficient to complete the discharge without the impeller spinning idly, and there is no problem in actual use. As mentioned above, it is said that the commonly known centrifugal pump cannot be used for pumping hot water, but it was determined that it could be used by suppressing the pump's discharge volume. When we conducted an experiment, we found that there were variations in the discharge amount, and in the end, the discharge was not possible. This is thought to be because the generally known centrifugal pumps have a spiral-shaped pump chamber with a large volume, which promotes the growth of air in the hot water and causes the impeller to spin idly. No effect is obtained.

The hot water supply device of the present invention directly discharges hot water using the centrifugal pump configured as described above, and is capable of stably dispensing hot water.

Embodiment Hereinafter, an embodiment of the present invention will be described based on the accompanying drawings. In Figure 1, 1 is the exterior body of the water heater, and inside is a container 2 (5.000 ml) for storing hot water.
degree). Reference numeral 3 denotes an inner stopper attached to seal the mouth of the container 2. Reference numeral 4 denotes an upper lid attached to the upper part of the exterior main body 1 so as to be able to be opened and closed. A check valve 5 communicates with the inside of the container 2 through the inner stopper 3, and also communicates with the atmosphere through the boiling detection section 6. 7 is a motor provided at the bottom between the exterior main body 1 and the container 2. A centrifugal pump 8 is driven by a motor 7, and its suction port 9 communicates with the bottom of the container 2. 10 is the discharge port of the centrifugal pump 8, through which the vortex is pumped upward through the pipe 25;
It is designed to be poured from a spout 11 into a cup or the like.

12 is a start switch for driving the motor 7; 13;
is a variable resistor, and the variable resistor 13 and the start switch 12 of the motor 7 are each operated via a rod 15 by pushing a push button 14 for starting the motor. 16 is a compression type spring, and this spring 16 always urges the rod 15 upward.

Next, the centrifugal pump 8 will be explained with reference to FIGS. 2 and 3. Reference numeral 17 denotes an impeller having radially arranged blades 17a, and a pump chamber 18 is formed by continuously providing a small gap t having a substantially constant width on a concentric circumference along the outer periphery of the impeller 17. The centrifugal pump of the example has a t=1.5 mm and an impeller rotation speed of 1600.
~3200rpm, discharge amount 30~80ml/sec. The diameter of the impeller 17 is 30φ, and the volume of the pump chamber 18 is set to be large enough to accommodate 5 c.c. of hot water. Note that the impeller 17 is fixed to the shaft 7a of the motor 7. 19 is a packing for sealing.

FIG. 4 is a circuit diagram, and 20 is a heating heater. This heater 20 is fixed to the lower side of the container 2 together with a heat-retaining heater 21, and heats the water in the container 2 to boil it. It maintains the state of hot water. 22 is a temperature switch provided on the bottom surface of the container 2, and this temperature switch 22 switches the contact point when a predetermined temperature is reached. 23 is a switch for keeping warm. 14 is a commercial power source, and this commercial power source 24 is a heater 20 for heating.
connected to one end of the Also, heater 2 for heating
0 is connected to a heater 21 and a temperature switch 22 for keeping warm. The other end of the heat-retaining heater 21 is connected to a temperature switch 22 via a switch 23. The heat-retaining heater 21 then taps out from an intermediate position, and from this tap point the motor 7
The variable resistor 13 and start switch 12 are connected in series and connected to a commercial power source 24.

The operation in the above configuration will be explained. When pouring hot water that has just been boiled in the container 2, pressing down on the push button 14 lowers the rod 15 and turns on the start switch 12.
It is turned on and the motor 7 is energized. As a result, the impeller 17 rotates, and the suction port 9 of the centrifugal pump 8
The hot water in the container 2 enters the pump chamber 18, is given a swirl while being pushed outward by the impeller 17, and is sent out from the discharge port 10 by centrifugal force. When the push button 14 is pressed further from this state, the resistance value of the variable resistor 13 is reduced in conjunction with the rod 15, so the rotation speed of the motor 7 gradually increases (from 1600 to 3200 rpm).As a result, The amount of hot water poured out also increases. In other words, by lightly touching the pushbutton 14 and then pushing it down, the power supply voltage can be gradually increased according to the amount of push-down, which eliminates the traditional method of dispensing indirectly through the air. Comparatively, stable dispensing can be performed. Further, since the power source for driving the motor 7 has a tap extending from the middle of the heater and obtains a low voltage from this tap point, it can be constructed in a small size and at low cost.

Generally speaking, centrifugal pumps cannot be used to pump hot water that is boiling or has just boiled, but in the centrifugal pump of this embodiment, which has a continuous gap t of approximately constant width, the pump Since the volume of the chamber 18 is small and the discharge flow rate is suppressed by the gap, there is little air intake, and
The growth of air is suppressed, and even if air grows, the amount of hot water is limited, so hot water can be discharged without the impeller spinning idly.

Effects of the Invention As described above, the present invention provides a hot water supply device that uses a centrifugal pump, which breaks the conventional wisdom.The centrifugal pump directly pours hot water from a container. Because of this, a larger amount of hot water than expected will not be poured out, and air will not be mixed in.
It has an excellent effect that has not been seen in the past: it is safe and there is no splashing of hot water.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a hot water supply system showing an embodiment of the present invention, Fig. 2 is a front view showing a part of a centrifugal pump incorporated in the same equipment in cross section, and Fig. 3 is a cross-sectional view of the same centrifugal pump. FIG. 4 is a partially sectional side view and is a circuit diagram of the water heater. 1... Exterior main body, 2... Container, 7... Motor,
8...Centrifugal pump, 20...Heating motor, 2
1... Heater for keeping warm.

Claims (1)

[Scope of Claims] 1. A device comprising: an exterior body, a container for storing hot water provided in the exterior body, and a heater for heating the water in the container; A centrifugal pump is provided for pumping water to a water inlet, and this centrifugal pump consists of an impeller driven by a motor, and a pump chamber in which a gap of approximately constant width is continuously provided on a concentric circumference along the outer periphery of the impeller. A water heater made up of. 2. The water heater according to claim 1, wherein the power supply voltage for driving the motor is varied in accordance with the variable amount of a push button for the motor track, and the discharge amount of the centrifugal pump is adjusted. 3. The water heater according to claim 2, wherein a tap is extended from a midway position of the heater, and a low voltage is applied to the motor from this tap point.