JPH062105B2 - Electric water heater - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric water heater that heats and heats a contained liquid.

2. Description of the Related Art Conventional electric water heaters without an inner lid are equipped with an outlet on the lower side wall or bottom wall of the container in order to draw the liquid in the container out of the container. A glass or metal pipe is connected to the outer surface of the container to form a flow path to the discharge port in the upper part of the container. Further, as shown in FIG. 6, the one using a liquid pump is
The outlet 42 of the lower side wall of the container 41 is connected to the liquid pump 44 by the connecting pipe 43, and the outlet 44a is led by the outlet pipe 45 through the water pipe bushing 47 having the built-in check valve 46.
When the liquid pump 44 is driven by the motor 49, the liquid in the container is led to the outside of the container.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in such a conventional configuration, the flow path through the liquid pump to the discharge port is long, and therefore, when boiling water, the water in the container is heated by the heating element. Thus, the water in this flow path is not sufficiently heated even when it reaches boiling. For this reason, when hot water is supplied to a cup outside the body, hot water that is not sufficiently heated first comes out in the flow path that includes the liquid pump, and hot water (90 ° C or higher) cannot be obtained. There was a problem that I could not meet the request. Further, even during the heat retention, the flow path was affected by the outside air, the temperature did not rise, and it was difficult to obtain hot water. For this reason, measures have been taken to shorten the flow path or bring the flow path closer to a high-temperature container, but this has not been sufficient.

Therefore, an object of the present invention is to provide an electric water heater capable of solving the above problems.

Means for Solving the Problems In order to solve the above problems, the electric water heater of the present invention arranges a bottomed cylindrical container in the body, and a heating element and a liquid temperature in the container at the bottom of the container. A first temperature detector for detection is provided, and a liquid outlet formed on the lower side wall of the container and a discharge outlet provided on the body side are connected by a lead-out conduit, and a lead-out conduit is provided in the middle of the lead-out conduit. A second temperature detector for detecting the liquid temperature in the pipe, a liquid pump,
And a branch portion having a switching valve for selectively guiding the liquid from the liquid pump to either the discharge port side or the container side, and the switching valve is operated to the container side. When the temperature detected by the second temperature detector is lower than the temperature detected by the first temperature detector, the liquid pump is operated to circulate the liquid in the outlet conduit into the container.

Action In the above-mentioned configuration of the present invention, a state in which hot water is not discharged,
That is, when the liquid temperature in the outlet pipe becomes lower than the liquid temperature in the container while the switching valve is switched to the container side,
The liquid in the outlet conduit is circulated in the container by the liquid pump, so the liquid temperature is always high immediately after the start of tapping.

Embodiment One embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

Reference numeral 1 denotes a body in which a cylindrical container 2 having a bottom is built in, and a discharge port 3 is provided on the upper portion thereof. Reference numeral 4 denotes a lid that covers the upper opening of the container 2, and a lock knob 5 provided on the front surface of the lid.
It can be opened and closed by pressing. The container 2
At the bottom of the heating element, a heating element 8 including an electric water heater 6 and a heat retaining heater 7 formed by stacking insulating plates on top and bottom is formed of a metal having good thermal conductivity such as an aluminum material and a copper material. It is fixed in a crimped state via 9 and the back plate 10. In addition, at the center of the bottom of the container 2, the container 2
A first temperature detecting element (first
A temperature detector) 11 is provided. As shown in FIG. 2, the first temperature detecting element 11 opens and closes the contacts 12 and 13 of the water heater 6 and the heat retaining heater 7 which are the heating elements 8. In addition, 14 is a steam port provided in the lid body 4 and communicates with the inside of the container 2. Reference numeral 15 denotes an outlet provided on the lower side wall of the container 2, and a water pipe bushing in which a container-side outlet pipe 16, a branch pipe (branch portion) 17, and a check valve 18 are incorporated.
The discharge port 3 is connected to the discharge port 3 through the discharge port side discharge pipe 20. A liquid pump 21 for discharging the liquid is arranged in the middle of the container side outlet pipe 16.

This liquid pump 21 has a motor 22 as shown in FIG.
The magnetic pole plate 23 fixed to the side of and the magnetic pole plate 26 fixed to the side of the impeller 25 in the casing 24 are connected by magnetic force. The pump chamber 27 formed inside the casing 24 is kept watertight by the partition plate 28 and the packing 29. When the motor 22 is rotated, as shown by the arrow A, the liquid inside the container 2 is sucked into the casing 24 through the suction port 24a at the substantially central tip of the casing 24,
It is sent out to the container side outlet pipe 16 from the ejection port 24b. Further, a second temperature detecting element (second temperature detector) 30 for detecting the temperature of the liquid therein is provided near the suction port 24a of the liquid pump 21 of the container side outlet pipe 16. By the way, the branch pipe 17 has the container side outlet pipe 16 in the middle of the main pipe portion 17a connecting the container side outlet pipe 16 and the discharge port side outlet pipe 20.
A bypass pipe portion 17b connected to the upper side wall of the above is provided, and a swing type switching valve 31 that selectively connects the main pipe portion 17a and the bypass pipe portion 17b is provided at this branch portion. The switching valve 31 is usually arranged so that the liquid flows toward the bypass pipe portion 17b, as shown by the solid line in FIG. 3, and the hot water switch 32 provided on a part of the display plate.
The liquid is made to flow toward the main pipe portion 17a, that is, to the discharge port 3 only when the ON operation is performed. Of course, at this time, the motor 22 of the liquid pump 21 is rotated. Further, when the tap water switch 32 is turned off, that is, when the switching valve 31 opens the bypass pipe portion, the temperature detected by the second temperature detecting element 30 is changed by the first temperature detecting element 11. When the temperature becomes lower than the detected temperature by a predetermined temperature, the pump switch 33 is turned on, the motor 22 is rotated, and the liquid inside the container side outlet pipe 16 is circulated to the container 2. These controls are for body 1
Is performed by the control circuit 34 arranged at the inner bottom of the. The container side and the discharge port side outlet pipes 16 and 20 form outlet pipes.

In the above structure, when the liquid temperature inside the container-side outlet pipe 16 becomes a predetermined value or lower than the liquid temperature inside the container in a state where hot water is not discharged, the liquid pump 21 is driven by the control circuit 34 and the container 2 It is returned to and circulated. When the liquid temperature inside the container side outlet pipe 16 becomes equal to the liquid temperature inside the container, the liquid pump 21 stops. Therefore, the discharged liquid is always at a high temperature even at the beginning of tapping. At the time of tapping, the switching valve 31 is operated to open the main pipe portion 17a and the liquid pump 21 is also driven.

Effects of the Invention According to the configuration of the present invention, when the liquid temperature in the outlet pipe becomes low during non-hot water, the liquid temperature in the outlet pipe is always high because the liquid temperature in the outlet pipe is circulated while returning to the container. Therefore, the dissatisfaction of the user that the hot water is thin immediately after the start of hot water can be resolved.

[Brief description of drawings]

1 to 5 show an electric water heater according to an embodiment of the present invention. FIG. 1 is an overall sectional view, FIG. 2 is an electric circuit diagram, and FIG. 3 is an enlarged sectional view of a branch pipe portion. FIG. 4 is a sectional view of the liquid pump, FIG. 5 is an overall perspective view, and FIG. 6 is an overall sectional view of a conventional example. 1 ... Body, 2 ... Container, 3 ... Discharge port, 6 ... Water heater, 7 ... Insulating heater, 11 ... First temperature detecting element, 16 ...
Container side outlet pipe, 17 ... Branch pipe, 17a ... Main pipe portion, 17b ... Bypass pipe portion, 20 ... Discharge port side outlet pipe, 21 ... Liquid pump, 22 ... Motor, 30 ... Second temperature detecting element, 31 ... Switching valve , 33 ... Control circuit.

Claims (1)

[Claims] 1. A cylindrical container having a bottom is arranged in a body, and a heating element and a first temperature detector for detecting a liquid temperature in the container are provided at the bottom of the container, and the container is formed on a lower side wall of the container. The discharge port of the liquid that has been discharged and the discharge port provided on the body side are connected by a discharge conduit, and in the middle of this discharge conduit,
A second temperature detector for detecting the temperature of the liquid in the outlet pipe, a liquid pump, and a branch portion having a switching valve for selectively guiding the liquid from the liquid pump to either the discharge port side or the container side. And the switching valve is operated on the container side, the liquid pump is operated when the temperature detected by the second temperature detector is lower than the temperature detected by the first temperature detector. An electric water heater that allows the liquid in the outlet pipe to circulate in the container.