JP2010266148A - Device and method of controlling temperature of water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a temperature control device and a temperature control method of a water heater capable of being continuously used at a constant hot water supply temperature even if a flow rate in supplying hot water is changed, being used extremely in safety, and having superior energy-saving performance by rationalizing the temperature control device. <P>SOLUTION: A temperature sensor 2 for measuring a water supply temperature and a flow rate sensor 3 for measuring a water supply amount are mounted at a side of a water inlet pipe P. A control device 1 is disposed to calculate the heat quantity necessary to achieve a desired hot water supply temperature on the basis of the measured water supply temperature and water supply amount. The control device 1 calculates a heating power distribution time to achieve the heat quantity necessary for the hot water supply temperature on the basis of heat quantity per power distribution of one second in a heater 4 of a heat exchanger 6. Feed-forward control is performed by a semiconductor relay 5 distributing power to the heater 4 only for the calculated heating power distribution time. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a temperature control device and a temperature control method for a water heater that can be used continuously at a constant hot water temperature even when there is a fluctuation in the flow rate of hot water, and can be used very safely.

  Various temperature control devices that employ feed-forward control that calculates the required amount of combustion heat of a burner from an incoming water temperature, an incoming water flow rate, and a set hot-water temperature have been proposed as temperature control devices for conventional water heaters (Patent Documents 1 and 2). reference).

  The water heater operation control device described in Patent Document 1 is devised so that even if the incoming water temperature sensor fails, the emergency operation can be performed without stopping the device. Is a control device provided with a controller that performs feed forward control by calculating the necessary amount of combustion heat using the incoming water temperature before the failure occurs while displaying the failure.

  On the other hand, the temperature control device of Patent Document 2 is a control device that enables a hot water whose temperature is controlled to a predetermined value at the start of pouring, and the above-mentioned incoming water until the integrated flow rate from the start of pouring reaches a predetermined integrated flow point. Feed-forward control based on the output of the temperature sensor is executed. In addition, there is described a hot water supply temperature control device that executes only feedback control based on a hot water temperature sensor or executes this feedback control after a predetermined integrated flow point is exceeded.

Japanese Patent No. 3079905 Japanese Patent No. 2908229

  These conventional temperature control devices are all used in a gas combustion type heat exchanger. However, since the gas combustion type heat exchanger indirectly heats the water inside the pipe from the outside of the pipe through which water has passed, there remains a problem that the heat transfer efficiency is deteriorated.

  Moreover, in Patent Document 2, the integrated flow rate from the start of hot water is calculated as a predetermined integrated flow point, and the control method is changed depending on whether or not this integrated flow point is exceeded. For this reason, there are disadvantages in that there are many uncertain elements as the temperature control device, such as the calculation accuracy of the integrated flow point and the effectiveness of the changed control method.

  Therefore, the present invention was created to solve the above-described problems. Even if there is a fluctuation in the flow rate of hot water, it can be used continuously at a constant hot water temperature, and can be used extremely safely, and temperature control can be performed. The purpose of the present invention is to provide a temperature control device and a temperature control method for a water heater that streamlines the apparatus and is excellent in energy saving.

In order to achieve the above object, the first means in the present invention is as follows.
In a temperature controller for a water heater that supplies hot water after heating water supplied from the water inlet pipe P into the heat exchanger 6 with the heater 4 in the heat exchanger 6,
A temperature sensor 2 for measuring the feed water temperature and a flow rate sensor 3 for measuring the feed water amount are attached to the inlet pipe P,
The amount of heat necessary for a predetermined hot water supply temperature is calculated from the measured water supply temperature and the amount of water supplied, and the necessary heating is performed until the predetermined hot water supply temperature is reached based on the amount of heat per second in the heater 4 in the heat exchanger 6. A control device 1 for calculating energization time;
The feedforward control is performed by the semiconductor relay 5 that energizes the heater 4 only during the calculated heating energization time.

  The semiconductor relay 5 of the second means is mounted on the upstream side of the temperature sensor 2 in the inlet pipe P, and is configured to cool the semiconductor relay 5 with the temperature of the water inside the inlet pipe P. .

  The third means is that in the semiconductor relay 5, the inlet pipe P to which the semiconductor relay 5 is attached or a mounting portion of the inlet pipe P is formed by a copper pipe P 1, and a copper cooling board 10 is provided on the copper pipe P 1. The semiconductor relay 5 is attached to the cooling panel 10.

  The fourth means includes an earth leakage breaker 8 in the energization circuit of the heater 4, and the earth leakage breaker 8 is activated when the control device 1 detects an abnormality in the water supply amount, the water supply temperature, and the hot water supply temperature. A safety device that shuts off, a temperature sensor 7 installed in the heat exchanger 6, and an emergency relay 9 that operates by linking to the temperature sensor 7, and the temperature sensor 7 is abnormal in the heat exchanger 6. This is provided with a double safety mechanism comprising an auxiliary safety device that activates the earth leakage breaker 8 via the emergency relay 9 when a high temperature is detected.

  The fifth means is a temperature control method for a water heater in which water supplied from the inlet pipe P into the heat exchanger 6 is heated to a predetermined temperature by the heater 4 in the heat exchanger 6 and then hot water is supplied. The water supply temperature and the water supply amount are measured, the amount of heat necessary for a predetermined hot water supply temperature is calculated from the measured water supply temperature and water supply amount, and the amount of heat per second of energization in the heater 4 in the heat exchanger 6 is calculated. Based on the temperature control method, the heating energization time until reaching a predetermined hot water supply temperature is calculated, and the heater 4 is energized only during the calculated heating energization time to perform feedforward control.

  As in the temperature control device of claim 1 and the temperature control method of claim 5 of the present invention, the amount of heat required for a desired hot water supply temperature is calculated from the measured feed water temperature and the amount of feed water, and the inside of the heat exchanger 6 is calculated. Feedforward control by the control device 1 that calculates the heating energization time until the hot water supply temperature is reached based on the amount of heat per second energization of the heater 4 and the semiconductor relay 5 that energizes the heater 4 only during the calculated heating energization time. With this configuration, even if there is a change in the amount of water supply, the water supply temperature can be instantaneously controlled on the water supply side, so that the temperature does not fluctuate easily and a uniform water supply temperature can always be maintained. In addition, since the water in the heat exchanger 6 is directly heated by the heater 4, the temperature control error is extremely small as compared with the gas burner.

  Further, since the semiconductor relay 5 is configured as in the second and third aspects, a heat sink for cooling the semiconductor relay 5 becomes unnecessary, and the efficiency of the apparatus can be improved. In other words, since the semiconductor relay 5 generates heat when a voltage is applied, the semiconductor relay 5 is normally cooled by attaching an expensive and large aluminum heat sink. Space is saved because it is unnecessary.

  In addition, since the water in the water intake pipe P that has cooled the semiconductor relay 5 is preheated even though the semiconductor relay 5 is cooled, the energy saving effect using the semiconductor relay 5 is achieved.

  Further, as in claim 4, when the control device 1 detects an abnormality in the water supply amount, the water supply temperature, and the hot water supply temperature, the leakage breaker 8 is activated to shut off the energization circuit, and the temperature sensor 7 is used for heat exchange. Since the dual safety mechanism including the auxiliary safety device that activates the earth leakage breaker 8 when an abnormally high temperature in the vessel 6 is sensed is provided, the feedforward control can be performed extremely safely.

It is the schematic which shows one Example of this invention temperature control apparatus. The mounting example of the semiconductor relay of this invention is shown, (A) is an exploded perspective view, (B) is a perspective view. It is a flowchart which shows this invention temperature control method.

  According to the present invention, even if the hot water flow rate fluctuates, it can be used continuously at a constant hot water temperature, can be used extremely safely, and the initial purpose such as streamlining temperature control and excellent energy savings, etc. Realized.

  An embodiment of the present invention will be described below with reference to the drawings. The main configuration of the control device of the present invention is a heat exchanger 6 for heating and storing hot water, a heater 4 in the heat exchanger 6, a temperature sensor 2 and a flow rate sensor 3 on the inlet pipe P side, and a heater 4. It comprises a control device 1 for controlling the energization time and a semiconductor relay 5 (see FIG. 1).

  That is, the temperature control device of the present invention is used for a water heater that supplies hot water after the water supplied from the inlet pipe P to the heat exchanger 6 is heated by the heater 4 in the heat exchanger 6.

  The heat exchanger 6 is provided with a temperature sensor 2 for measuring the temperature of the water supply and a flow rate sensor 3 for measuring the amount of water supply. On the other hand, a control device 1 is provided that calculates the amount of heat required to reach a desired hot water supply temperature from the water supply temperature and the water supply amount measured by the temperature sensor 2 and the flow rate sensor 3.

  The control device 1 calculates the heating energization time until the desired hot water supply temperature is reached based on the amount of heat per second of energization in the heater 4 in the heat exchanger 6, and the heater 4 only for the calculated heating energization time. Is controlled to energize. In the embodiment, the semiconductor relay 5 is mounted on the energization circuit to the heater 4, the semiconductor relay 5 is energized only for the heating energization time calculated by the control device 1, and the heater 4 is heated for this energization time. Thus, the temperature control device of the present invention is configured to feed-forward control the hot water supply temperature.

  In general, the semiconductor relay 5 can be used for a long time as a contactless relay. Since the semiconductor relay 5 generates heat when a voltage is applied, the semiconductor relay 5 is usually cooled by attaching an expensive aluminum heat sink. Therefore, in the temperature control device of the present invention, instead of the heat sink, the semiconductor relay 5 is cooled using the temperature of the water at the time of water supply, and the water supply temperature can be heated by the heat generated by the semiconductor relay 5. ing.

  That is, the semiconductor relay 5 is mounted on the upstream side of the temperature sensor 2 mounting position of the inlet pipe P. At this time, the entire inlet pipe P to which the semiconductor relay 5 is attached may be formed of the copper pipe P1, or only a part of the inlet pipe P to be attached may be formed of the copper pipe P1. And the copper cooling board 10 is fixed to this copper pipe P1 (refer FIG. 2). In the illustrated example, the efficiency of the heat exchange ratio is increased by mounting the cooling board 10 along the longitudinal direction of the copper pipe P1 so that the contact area between the copper pipe P1 and the cooling board 10 is increased (the same figure). (See (i)). Further, the semiconductor relay 5 is mounted on the cooling panel 10 (see FIG. 7B). By mounting in this way, the semiconductor relay 5 can be cooled at the temperature of the water inside the water intake pipe P. Moreover, an energy saving structure in which the feed water temperature is heated by the heat generated by the semiconductor relay 5 can be achieved.

  Furthermore, in the feedforward control according to the present invention, the necessary heat amount of the heater 4 is calculated from the feed water temperature, the feed water amount, and the desired hot water supply temperature, so that a safety device in the event of a malfunction in the temperature sensor 2, the flow sensor 3, etc. As a result, the control device 1 is equipped with a safety device function. In this safety device, an earth leakage breaker 8 is installed in the energization circuit of the heater 4, and when the control device 1 detects an abnormality in the water supply amount, the water supply temperature, and the hot water temperature, the earth leakage breaker 8 is activated to interrupt the energization circuit. It is configured.

  Furthermore, when the control device 1 breaks down, the safety device mounted on the control device 1 does not function. Therefore, in the present invention, an auxiliary safety device is further mounted. This auxiliary safety device is provided with a temperature sensor 7 installed in the heat exchanger 6 and an emergency relay 9 that operates by linking to the temperature sensor 7, and the temperature sensor 7 is abnormal in the heat exchanger 6. When a high temperature is sensed, the earth leakage breaker 8 is activated via the emergency relay 9, and the earth leakage breaker 8 is configured to cut off the energization circuit in the same manner as the safety device. By providing the double safety mechanism in this way, the feedforward control can be executed extremely safely.

  The temperature control method of the present invention is a method using the temperature control device, and is a process shown in FIG. First, the inlet water P measures the water supply temperature and the amount of water supply (STEP 1 and STEP 2). Next, the amount of heat necessary for the desired hot water supply temperature is calculated from the measured water supply temperature and water supply amount (STEP 3). At this time, when there is no need for energization, such as when the feed water flow rate is below a certain value (for example, 3 l / m), the process returns to STEP 1. In STEP 3, the heating energization time until reaching the hot water supply temperature is calculated based on the amount of heat per second of energization in the heater 4 in the heat exchanger 6. Further, the semiconductor relay 5 is energized only for the calculated heating energization time (STEP 4). Thereafter, the heater 4 is energized only during the heating energization time, and the hot water supply temperature is controlled to a desired temperature.

  The temperature control device of the present invention is not limited to the illustrated example, and design changes can be freely made without changing the gist of the present invention.

  According to the present invention, it can be used for all types of water heaters capable of implementing the temperature control device and the temperature control method of the present invention.

P Inlet pipe P1 Copper pipe 1 Controller 2 Temperature sensor 3 Flow rate sensor 4 Heater 5 Semiconductor relay 6 Heat exchanger 7 Temperature sensor 8 Earth leakage breaker 9 Emergency relay 10 Cooling panel

Claims (5)

In a temperature control device for a water heater that supplies hot water after heating water supplied from a water intake pipe into the heat exchanger with a heater in the heat exchanger,
A water inlet pipe is equipped with a temperature sensor that measures the feed water temperature and a flow sensor that measures the feed water amount,
Calculate the amount of heat required for the predetermined hot water supply temperature from the measured water supply temperature and the amount of water supply, and calculate the heating energization time until the predetermined hot water supply temperature is reached based on the amount of heat per second of energization in the heater in the heat exchanger. A temperature control device for a water heater, which is configured to perform feedforward control by a control device that calculates and a semiconductor relay that energizes the heater only during the calculated heating energization time.   The temperature control device for a water heater according to claim 1, wherein the semiconductor relay is mounted on the water inlet pipe and is configured to cool the semiconductor relay with a temperature of water inside the water inlet pipe.   In the semiconductor relay, the water intake pipe to which the semiconductor relay is attached or a mounting portion of the water intake pipe is formed of a copper pipe, a copper cooling board is fixed to the copper pipe, and the semiconductor relay is attached to the cooling board. Item 3. A temperature control device for a water heater according to item 1 or 2.   A safety device that includes an earth leakage breaker in the heater energization circuit, and that the earth leakage breaker operates to shut off the energization circuit when the control device detects an abnormality in the water supply amount, water supply temperature, and hot water temperature, and the heat exchange. A safety sensor comprising a temperature sensor installed in a vessel and an emergency relay that operates in linkage with the temperature sensor, and when the temperature sensor senses an abnormally high temperature in the heat exchanger, an earth leakage breaker is activated via the emergency relay. A temperature control device for a water heater according to claim 1, further comprising a double safety mechanism comprising the device.   In a temperature control method for a hot water heater in which water supplied from the inlet pipe to the heat exchanger is heated to a predetermined temperature by a heater in the heat exchanger, the inlet pipe measures the feed water temperature and quantity of water. Calculating the amount of heat necessary for a predetermined hot water supply temperature from the measured water supply temperature and the amount of water supply, and heating energization time until the predetermined hot water supply temperature is reached based on the amount of heat per second of energization in the heater in the heat exchanger And a feedforward control by energizing the heater only during the calculated heating energization time.

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