JPH06221671A - Valve controller for hot water heater - Google Patents

Abstract

PURPOSE:To stop a motor for a hot water heater at a position where a gas supply cock is effectively closed in the case of an overload malfunction of the motor, a trouble of a microswitch, etc. CONSTITUTION:The valve controller for a hot water heater comprises a water supply/stop cock 20 provided in a water supply tube 16 or a supply hot water tube 18 of a heat exchanger 12, a gas burner 14 for heating the exchanger 12, a gas supply cock 24 having a magnet safety valve 74 and an implement plug 76, and a motor 99 connected to the cock 20, the valve 74 of the cock 24 and the plug 76. The rotary position of the motor 99 is sensed by a combination of ON/OFF signal from first and second cam switches 110, 112 for detecting opening/closing of the cock 20 and opening/closing positions of the valve 74 and the plug 76. When signal from any switch is not input in a predetermined time, the motor 99 is stopped by a microcomputer in a position where the valve 74 of the cock 24 and/or the plug 76 is closed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water heater used in kitchens of general households, and more particularly to a water supply stopcock and a water supply stopper for one rotation of a cam linked with a motor by a motor drive system. The present invention relates to a valve control device for a water heater equipped with a system in which a magnet safety valve of a gas stopper and a device stopper are opened at different timings to perform a series of operations until combustion or extinguishing.

[0002]

2. Description of the Related Art Conventionally, as a water heater of this type, a motor is driven by turning on an ignition switch, a water stop cock is opened while a cam interlocked with the motor makes one revolution, and then a gas supply is performed. There is known a so-called motor drive system in which a magnet safety valve of a plug and a device plug are sequentially opened, and a gas burner is ignited by an igniter to obtain hot water.

A water heater of this type is usually equipped with a micro switch for detecting the opening of a water tap and a micro switch for detecting that a magnet holding current of a magnet safety valve is turned on. Four state positions, that is, the stop cock is opened by the combination of the ON / OFF signals from these two micro switches, that the magnet holding current is turned on, and that combustion is started and stopped. Is detected. Figure 7
Shows conceptually a series of these operations, these four positions are a system in which the motor is turned on when the conditions at each position are satisfied and the motor moves to the next position. .

[0004]

However, when the position of the cam cannot be detected due to a failure of the micro switch or the like, the motor keeps rotating and the opening and closing of each gas valve is repeated. Although gas does not leak, raw gas is released from the gas burner when either the magnet safety valve in the gas supply valve or the device stopper has a malfunction due to valve opening failure. In this case, the time during which the raw gas leaks from the gas burner while the motor is rotating is at most 0.2 seconds to 0.
If the stop position is not specified for about 5 seconds, if the magnet safety valve or the valve that does not have a valve closure failure is stopped at the open position, both valves will be open and the raw gas will be released continuously. There was a fear.

When the motor is locked due to an overload abnormality of the motor or when the position of the motor cam cannot be detected due to a failure of the micro switch or the like, the motor continues to rotate, and the battery is exhausted as it is. There was also the problem of being forced.

The present invention has been made to solve such a problem, and a main object of the present invention is to provide a gas burner when an abnormality such as an overload abnormality of a motor or a failure of a micro switch occurs. It is an object of the present invention to provide a valve control device for a water heater, which surely stops the motor at a safe position where the gas supply plug is closed so that raw unburned gas is not released. Thus, even if a part of a plurality of gas valves overlaps with the valve closing failure, leakage of raw gas does not occur and the safety of the water heater is improved.

Another object of the present invention is also to stop the driving of the motor in the event of an overload abnormality of the motor or a failure of the microswitch, thereby minimizing the consumption of the battery. Still another object of the present invention is to smoothly shift to normal operation by checking the origin of the motor when restarting the motor when the motor overloads abnormalities or the microswitch fails, and when the batteries are replaced. There is also something to achieve.

[0008]

To achieve this object, a water heater according to the present invention comprises a heat exchanger provided with a water supply pipe or a hot water discharge pipe, and a water supply stop provided on the water supply pipe or the hot water discharge pipe. A faucet, a burner for heating the heat exchanger, a gas supply plug including a magnet safety valve and a device stopper connected to the burner, a magnetic safety valve and a device stopper of the water stopcock and the gas stopper. Turn on / off the motor to be linked
By combining an ignition switch for turning off, a plurality of detection switches for detecting the opening / closing of the water stop cock and the opening / closing positions of the magnet safety valve of the gas supply stopper and the instrument stopper, and a combination of ON / OFF signals from the plurality of detection switches. When a signal from at least one of the plurality of detection switches is not input within a predetermined time due to a detection signal from the motor position detection means for detecting the rotational position of the motor, the feed The gist of the present invention is to include a motor stop position control means for controlling the motor so that the motor is stopped at a position where the magnet safety valve of the gas plug and / or the instrument plug is closed.

Further, the water heater of the present invention further comprises an origin position check means for checking the origin position of the motor when the motor stopped by the control of the motor stop position control means is re-driven. It is convenient.

[0010]

According to the water heater of the present invention having such a structure, when the motor is driven by the ignition operation of the ignition switch, the water stop cock is opened, then the gas supply cock is opened, and the burner is further opened. Is ignited, the water flowing through the water supply pipe of the heat exchanger is heated, and hot water is discharged from the hot water discharge pipe. At this time, a series of flows such as opening / closing of the water stop cock, ON / OFF operation of the magnet holding current, start of combustion and stop of hot water are ON / OF of a plurality of micro switches accompanying the rotation of the motor.
Although detected by the combination of the F signals, if the ON / OFF signals from these micro switches are not sequentially input within a predetermined timer setting time, at least at the position where the gas stopper is closed by the control by the motor stop control means. The motor is stopped. Therefore, it is avoided that unburned raw gas is continuously discharged from the burner while the motor is stopped. It is also possible to prevent the motor from being left energized due to an overload abnormality of the motor, a micro switch failure, or the like.

Further, if the origin position checking means for restarting the motor is provided, the origin position of the motor is checked when the stopped motor is re-driven under the control of the motor stop position control means. Therefore, if the motor is once stopped at the origin position and the normal operation is restarted from the origin position, the normal operation can be smoothly performed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of a main stopper type water heater as an embodiment of the present invention. As shown in the figure, this hot water heater 10 has a heat exchanger 12 including a water supply pipe 16 and a hot water discharge pipe 18 in the main body of the appliance.
And a gas burner 14 for heating the heat exchanger 12.
And are placed. And, the water supply pipe 16 is provided with a stopcock 2
0 is connected, and a gas supply plug 24 is connected to the source of the gas pipe 22 for supplying gas to the gas burner 14.

The water stop cock 20 is provided with a diaphragm chamber 28 in a water supply passage in the stopper, and a faucet diaphragm 26 is arranged so that a valve opening 30 leading to the diaphragm chamber 28 can be opened and closed. It A valve opening 32 is provided at a central portion of the faucet diaphragm 26 corresponding to the valve opening 30, and the valve opening 32 is attached to the tip of a valve shaft 36 penetrating the stopper wall of the water stop cock. The attached water faucet pilot valve 34 is normally provided via a spring 38 in a state of being pressed and biased so as to close the valve opening 32.

Further, the faucet diaphragm 26 is provided with a water passage hole 40 in addition to the valve port 32. When the valve port 32 is closed by the faucet pilot valve 34, the water pressure in the water supply passage is related. Water in the water supply channel enters the back side of the faucet diaphragm 26 through the water passage 40, and the closed state of the faucet pilot valve 34, that is, the closed state of the valve opening 30 of the diaphragm chamber 28 is maintained, The water stopcock 20 is configured to be kept in a water-stopped state.

The diaphragm chamber 28 is partitioned by a hydraulic diaphragm 42 into a primary pressure chamber 44 and a secondary pressure chamber 46, and the hydraulic diaphragm 42 is located on the primary pressure chamber 44 side.
A water amount adjusting valve 48 for adjusting the amount of water flowing into the diaphragm chamber 28 from the valve port 30 is attached to the surface via a spring 50, and the water amount adjusting valve 48 adjusts the flow rate of water flowing through the water supply passage. It has become so.

The water that has flowed into the primary pressure chamber 44 is supplied to the water supply pipe 16 and the hot water supply pipe through a communication water passage 54 of a water amount restricting shaft 52 that is rotatably provided in a stopper wall of the water stopcock 20. 18 are distributed and supplied respectively to the water amount throttle shaft 5
By rotating 2, the flow rate of water supplied to the water supply pipe 16 and the mixing amount of water to the hot water flowing through the hot water discharge pipe 18 can be adjusted.

A water temperature adjusting lever 5 is attached to the water amount throttle shaft 52.
6 are connected, and a hot / cold water changeover switch 58 for detecting the rotation of the water amount throttle shaft 52 rotated by the operation of the hot water temperature adjusting lever 56 is provided in proximity. By rotating the hot water temperature adjusting lever 56, the water amount restricting shaft 52 is rotated to adjust the distribution amount of water distributed and supplied to the water supply pipe 16 and the hot water discharge pipe 18. By turning 56 to the “water” position, the hot and cold water switch 58 is turned on, and the operation of the ignition switch (which will be described later in detail) for igniting the gas burner 14 is not accepted and the water of the water tap 20 is not received. Stop pilot valve 34
It is configured such that only the water is opened and only the water is discharged from the hot water discharge pipe 18.

The secondary pressure chamber 4 of the diaphragm chamber 28
The 6 side is communicated with a venturi pipe portion 64 provided in the water supply pipe 16 through a bypass pipe line 62, and when water is flowing through the water supply pipe 16, the secondary pressure chamber 46 becomes a negative pressure from the primary pressure chamber 44. As the water amount control valve 48 moves leftward as shown by the arrow in FIG. 1, the automatic water pressure valve 70 provided in the gas flow path of the gas supply plug 24 is opened and the water flow detection switch 86 is turned on at the same time, as described later. It is like this.

Reference numeral 60 in FIG. 1 is a water amount control valve for adjusting the amount of water sent to the water supply pipe 16 via the communication water passage 54 of the water amount throttle shaft 52. Reference numeral 66 is a drain plug provided in the secondary pressure chamber 46. Further, reference numeral 68 is this stop cock 2
The strainers provided at the water inlet to 0 are each shown.

On the other hand, the feed gas plug 24 provided in the gas pipe 22 of the gas burner 14 has the above-mentioned water pressure for opening and closing the valve port 78 in the feed gas flow passage inside the plug in association with the movement of the water amount control valve 48. An automatic valve 70, a gas governor 72 that adjusts the opening degree of a valve opening 88 according to the gas pressure in the supply gas passage, and a valve opening 94 near the gas inlet of the supply gas plug 24 for preventing ignition troubles and the like. A magnet safety valve 74 provided in
An instrument plug 76 provided at the valve opening 97 for opening and closing the gas supply passage is provided.

Here, the automatic hydraulic valve 70 has a valve shaft 82 which is inserted into the stopper wall of the gas supply plug 24 and the stopper wall of the water stop cock 20 and is connected to the hydraulic diaphragm 42 in the diaphragm chamber 28 to supply water. In the water-stopped state in which the water is not flowing through the water stopcock 20, the valve opening 78 is kept closed by the spring 80. A switch actuating piece 84 is provided in the middle of the valve shaft 82, and the water flow detection switch 86 which is turned on by the switch actuating piece 84 is provided beside the valve shaft 82, and the water stop cock is provided. Water flows to 20, and the water flow detection switch 86 is turned on by the switch operating piece 84.
The motor 99, which will be described later, is driven to start the ignition operation.

In addition, the opening of the valve opening 88 of the gas governor 72 is adjusted via a spring 90 that expands and contracts according to the gas pressure in the gas supply passage, and the magnet safety valve 74 is The valve opening 94 is opened and closed by the operation of the built-in electromagnet. Further, the instrument plug 76 is attached to the tip of a valve shaft 98 that is inserted through the plug wall of the gas supply plug 24, and is normally pressed by a spring to close the valve port 97.

Thus, the motor 99, which is a drive source that is driven in conjunction with the ignition switch to open and close the water tap 20 to discharge or stop hot water, has first to third motor cam shafts linked to its drive shaft. Cams 100, 102, 1
04 is provided, and the first cam 100 is connected to a water stop cock opening / closing lever 108 for opening / closing the water cock pilot valve 34 via a motor interlocking lever 106.
The water stop cock opening / closing lever 108 is connected to the base of the valve shaft 36 of the water stop pilot valve 34, and the valve shaft 36 moves forward and backward by the operation of the water stop cock opening / closing lever 108.
Valve port 3 closed by the faucet pilot valve 34
2 is opened and closed.

The second cam 102 is connected to the valve shaft 98 of the appliance stopper 76, and the third cam 104 penetrates the stopper wall of the gas supply stopper 24 to magnetize the electromagnet contained in the magnet safety valve 74. It is connected to a safety valve operating rod 96 provided by being inserted. Then, the first cam switch 110 and the second cam switch 1 for detecting the rotational positions of the first cam 100 and the second cam 102 in the vicinity of the motor 99.
12 is provided, and the combination of the ON / OFF signals from the first and second cam switches 110 and 112 opens the faucet pilot valve 34 of the water stopcock 20, and a magnet safety valve. The current of 74 is turned on to open the magnet safety valve 74, the appliance stopper 76 is also opened and the burner is ignited to start combustion, and all of the stop water tap 20, the magnet safety valve 74, and the appliance stopper 76. The fact that the hot water is closed and the hot water is stopped is detected.

The first and second cam switches 110, 1
Water stopcock 2 by combination of ON / OFF signals from 12
0 (water pressure automatic valve 70), the open / closed state of the magnet safety valve 74 and the instrument plug 76 (which also represents the rotation angle of the motor cam of the motor 99) are as shown in Table 1 below. The description of the operation according to Table 1 will be given later.

[0026]

[Table 1]

An operation panel (not shown) of the instrument body is provided with an operation button 114 and an ignition switch 116 which is turned on by pressing the operation button 114.
The motor 99 is rotationally driven by the ON operation of.

Further, reference numeral 118 in FIG. 1 indicates a gas burner 14.
The electrode for igniting the gas supplied to
Indicates a primary thermocouple for detecting the temperature of heat in the vicinity of the gas burner 14, and reference numeral 122 indicates a secondary thermocouple provided in the peephole of the casing wall for detecting the temperature of the combustion gas in the heat exchanger 12. .

Therefore, the water heater 1 configured as described above
When the operation of No. 0 is described with reference to Table 1 described above, the ignition switch 116 is turned on by pressing the operation button 114, and the motor 99 is turned on and driven. As a result, the motor interlocking lever 106 is pushed up by the rotation of the motor cam linked to the drive shaft of the motor 99, the water stop cock opening / closing lever 108 is rotated, and the faucet valve shaft 36 is pushed down. Moves backward, the valve port 30 leading to the diaphragm chamber 28 opens, and water flows into the diaphragm chamber 28.

A part of the water is sent to the water supply pipe 16 through the communication water passage 54 of the water amount throttle shaft 52, and the remaining water is sent to the hot water discharge pipe 18.
The first cam switch 1
10 is turned on, the motor 99 turns the first cam switch 1
It is once stopped at a position where 10 is turned on (that is, a position where the water stop cock 20 is open). In this case, the second cam switch 112 is still in the OFF state.

At this time, the water sent to the water supply pipe 16 passes through the Venturi pipe portion 64, so that the pressure in the diaphragm secondary pressure chamber 46 of the diaphragm chamber 28 is lowered, and the hydraulic diaphragm 42 moves leftward in FIG. As a result, the valve shaft 82 that connects the water amount control valve 48 and the automatic water pressure valve 70 of the gas supply plug 24 also moves to the left in FIG. 1, and accordingly the hydraulic pressure automatic valve 70 in the gas supply plug 24 opens. At the same time, the water flow detection switch 86 is turned on.

O from the water flow detection switch 86
The igniter is turned on by the N signal, the continuous spark of the ignition electrode 118 is started, the motor 99 is driven again, and the magnet safety valve operating rod 96 is gradually pushed by the third cam 104 as the motor rotates. The second cam switch 112 is also turned on. And this second
When the cam switch 112 is turned on, the magnet holding current of the magnet safety valve 74 is turned on, whereby the magnet safety valve 74 is electrically conductive and the built-in electromagnet is excited, so that the magnet safety valve 74 is opened. Retained.

The motor 99 continues to be driven in the ON state, and then the valve shaft 98 of the instrument stopper 76 is pushed down by the second cam 102 to open the instrument stopper 76. At this time, the first cam switch 110 is turned off and the At the position where the 1-cam switch 110 is turned off (combustion), the driving of the motor is stopped again. At this time, the second cam switch 112 is O
It remains in the N state.

Thus, the supply gas passage in the supply gas plug 24 is completely opened, the gas is supplied to the gas burner 14, and the gas burner 14 is ignited by the continuous spark of the ignition electrode 118 described above. The igniter is turned off 2 seconds after the OFF signal of the first cam switch 110.

The water passing through the water supply pipe 16 leading to the heat exchanger 12 is heated by the gas burner 14 and discharged from the hot water discharge pipe 18. At that time, the water flows to the hot water discharge pipe 18 through the communication water passage 54 of the water amount throttle shaft 52. By mixing the water sent directly, the hot water will continue to be heated in a state where the temperature is adjusted to an appropriate temperature.

On the other hand, when the hot water discharge is stopped, the operation button 114 is pressed again at the combustion stop position of the motor cam to turn on the ignition switch 116, so that the current holding the magnet safety valve 74 is released and the magnet is turned off. The safety valve 74 is closed and the gas flow in the gas supply plug 24 is stopped. As a result, the gas burner 14 is extinguished, and at the same time, the motor 99 is turned on and driven again, and the motor is stopped at the OFF (stop) position of the second cam switch 112.

At this point, the water stop cock opening / closing lever 108 also returns to its original state, and the water cock pilot valve 34 is closed.
Further, the instrument plug 76 is also closed, the water supply flow passage is blocked, and the gas supply flow passage is completely cut off, so that hot water is stopped. In this state, both the first cam switch 110 and the second cam switch 112 are off.

FIG. 2 shows that when the rotational position of the cam of the motor cannot be detected due to a failure of the micro switch or the like, the electric load such as the magnet safety valve 74 and the igniter is temporarily turned on.
After the FF, only the motor 99 is turned on to be rotationally driven, and the rotation angle of the motor cam by the drive of the motor 99 and the first cam switch 110 and the second cam switch 112.
Shows the relationship between the ON / OFF timing of ON / OFF, the opening / closing of the water stopcock 20, the ON / OFF timing of the magnet holding current of the magnet safety valve 74 of the gas supply tap 24, the opening / closing timing of the magnet safety valve 74, and the like. ing.

On the horizontal axis, the rotation angle of the motor cam is 0 ° to 3 °.
Shown up to 60 °, the vertical axis indicates the ON / OFF timing of the first cam switch 110 and the second cam switch 112, and the magnet holding current ON (HI and LO) / OFF.
And the timing of opening and closing the magnet safety valve 74 and the instrument stopper 76, respectively.

As is apparent from FIG. 2, as the cam of the motor rotates, first the first cam switch 110 is turned on to open the water stopcock 20, and then the magnet safety valve 74 is changed to the safety valve by the third cam 104. It is gradually opened by the pressing action of the operating rod 96, and the second cam switch 112 becomes O.
At the time of N, normally the magnet holding current is turned on and the magnet safety valve 74 is held in the open state as shown by the alternate long and short dash line in the figure. Next, the instrument plug 76 is gradually opened by the pushing up action of the valve shaft 98 by the second cam switch 112, and becomes completely opened when the first cam switch 110 is turned off. Then, as the motor cam further rotates, the second cam switch 112 is turned off.
FF is performed and the water stopper 20 and the instrument stopper 76 are closed.

Since this timing chart shows the state in which the holding current of the magnet safety valve 74 is not energized, there is no state in which the magnet safety valve 74 and the instrument stopper 76 are open at the same time, and before the instrument stopper 76 is opened. It can be seen that the magnet safety valve 74 is already closed.

When an abnormality such as an overloaded state of the motor or a failure of the cam switch occurs during the timing of such a series of motor driving and each operation, the following FIGS.
The abnormality is detected in accordance with the motor overload abnormality sequence flow shown in (1) or its flowchart, and the motor is stopped at a safe position where it is not released from the unburned gas burner 14.

The control when the motor overload is abnormal will be described with reference to the flowchart shown in FIG. 4. Now, the motor 99 is normally rotationally driven and controlled by the operation of the ignition switch 116 (step 1, hereinafter simply referred to as " S1 ")), if the following signal is input from the first cam switch 110 or the second cam switch 112 within T seconds, it is determined that the operation is normally controlled without an overload condition of the motor. However, if it is determined that the next signal is not input for T seconds or more (S2), it is determined that the motor overload abnormality has occurred by the computer incorporated in the water heater.

Therefore, the motor 99 and the magnet safety valve 74
Or all electrical loads such as igniter are turned off once
(S3). The set time of the timer "T seconds" is here between the respective positions such as the opening operation of the water shutoff valve, the ON operation of the magnet current, and the opening operation (combustion start) of the instrument plug in accordance with the normal rotation of the motor. The time is set to be about five times the time required to move.

Next, only the motor 99 is turned on (S4),
At this time, first, it is determined whether or not the second cam switch 112, which is directly related to the opening / closing operation of the magnet safety valve 74 of the gas supply plug 24 and the appliance plug 76, is turned on (S5), and the second
If it is determined that the cam switch 112 is turned on, it is then determined whether the second cam switch 112 is turned off (S6), and the motor 99 is turned off when it is determined that the second cam switch 112 is turned off. To be done.

As is clear from Table 1, this is because both the first cam switch 110 and the second cam switch 112 are in the OFF state, and the water stop cock 20 (including the automatic water pressure valve 70 of the gas stop 24). Also, both the magnet safety valve 74 of the gas supply plug 24 and the instrument plug 76 are closed. If the motor 99 is turned off at this position, the raw gas is not sent from the feed gas plug 24 to the gas burner 14, and the raw gas does not leak when the combustion is stopped.

In S5, the second cam switch 112
When it is determined that the ON signal of is not input, and S
When it is determined that the OFF signal of the second cam switch 112 is not input in 6, it is determined whether the next signal is not input from the first cam switch 110 or the second cam switch 112 within T seconds (S7, And S8),
If there is no input signal within T seconds, it is next determined whether or not the first cam switch 110 is turned off (S9).

Then, in S9, the first cam switch 11
When it is determined that 0 is turned off, it is then determined whether the first cam switch 110 is turned on or whether the water flow detection switch 86 is turned off (S1).
0, and S11), if it is determined that the first cam switch 110 is turned on, or if the water flow detection switch 86 is turned off, the motor 9
9 is turned off.

When the motor 99 is turned off based on the determination at S10, this means that the magnet safety valve 74 of the gas supply plug 24 and the instrument plug 7 are just opened even though the stop cock 20 is open.
6 is in a closed state, the flow of gas in the feed gas plug 24 is stopped, and in this case also, leakage of raw gas from the gas burner 14 does not occur. At this time, since only the water shutoff tap 20 is opened, water flows out from the hot water outlet pipe 18, but this is stopped by closing the original water tap (not shown). At this time, the automatic water pressure valve 70 in the gas supply plug 24 is also closed at the same time.

On the other hand, when the motor 99 is turned off based on the determination in S11, this is the OF of the water flow detection switch 86.
This means that the automatic water pressure valve 70 of the gas supply plug 24 is closed by the F signal, and at the same time, as is clear from the timing chart shown in FIG.
Since the magnet safety valve 74 of 4 and the instrument stopper 76 should both be closed, in this case as well, the gas supply stopper 24
Therefore, the gas flow is stopped, and the raw gas does not leak from the gas burner 14.

Incidentally, at S9, the first cam switch 110
When it is determined that is not turned off, if it is determined that the next detection signal is not input and the position of the motor cam is not detected within T seconds (S12), the motor 99 is turned off. Further, in S11, the water flow detection switch 86 is turned off.
Even if it is not determined that the motor cam position is not detected within T seconds, the next detection signal is not input (S13), and the motor 99 is turned off.

In any of S9 and S11, the rotational position of the motor cam of the motor 99 is not known, but as is clear from the timing chart of FIG. 2, the magnet safety valve 74 is not energized at the time of abnormality inspection such as switch failure. Magnet safety valve 7
Motor 9 with both 4 and instrument plug 76 open
Since 9 is not stopped, the problem of leakage of raw gas from the gas burner 14 does not occur.

After that, the operation switch is turned off and reset. The reset is performed by repairing an overload abnormality of the motor or replacing a failed switch. In the flow chart of FIG. 4, if the determinations in S7 and S8 are “NO”, the second cam switch 11
2 means a failure, and the judgments in S12 and S13 are "NO".
If so, it means a failure of the first cam switch 110.

In this way, the water heater is restarted after the overload abnormality of the motor is eliminated, the failure switch is replaced, or the exhausted dry battery is replaced. In that case, It is necessary to return the stop position of the motor cam to the origin position where the cam rotation angle is 0 °.

In that case, control is performed according to the flow chart shown in FIG. In this figure, the case of replacing the dry battery is shown as an example, but when a new dry battery is firstly inserted (S21) and then the motor 99 is turned on (S22), the first cam switch 110 is turned off and the second cam is turned on. It is determined whether the cam switch 112 is turned on (S23). This is clear from the table above,
This is a judgment as to whether or not the rotation angle of the motor cam has just come to the "burning" position.

Next, when "YES" is determined in this S23, it is then determined whether both the first cam switch 110 and the second cam switch 112 are turned off (S24), and "YES" here as well. , The motor 99 is turned off and stops (S2
5). This is a judgment as to whether or not the rotation angle of the motor cam has just reached the "stop" position, as is clear from the above table.

Thus, the first determination in S23 is to determine the motor cam to be in a state just before the origin (stop position),
The next determination in S24 is to confirm the origin (stop position) of the motor cam, whereby the motor 99 is stopped exactly at the origin (stop position) of the cam.

By this origin check control, the deviation of the timing from the valve opening of the water shutoff valve to the combustion when the water heater is restarted is eliminated, and no trouble occurs during standby. This origin check operation is performed in a state where only the motor is electrically energized, and the igniter discharge and the magnet attraction current energization are stopped.

Incidentally, when the cam switch is already at the normal origin position, it is desirable that the motor cam should not be unnecessarily rotated. In this respect, according to the flow chart shown in FIG. 5, it is ensured that the motor makes one revolution. It will be stopped. In addition, when it takes more than a specified time between the detection positions by each micro switch during the origin check or during the normal motor rotation, the motor overload abnormality is detected by the combination with the flow charts shown in FIG. 3 and FIG. Alternatively, it is determined that there is an abnormality such as a failure of the micro switch, and the overload is detected. Further, since ON / OFF of the next cam switch at each position is determined, abnormality of the cam switch is also detected based on the behavior of the cam switch.

When it is not possible to return to the origin (stop position) due to an abnormality in the cam switch when abnormality detection is stopped,
It is even better to search for a safe stopping point and then stop. Thus, in this embodiment, the cams connected to the motor 99 are used to open the water stopcock 20, the device stopper 76, and the magnet safety valve 74 at different timings, but FIG. 6 shows the first cam switch 110 and the second cam switch 110. As shown in the relationship between the cam switch 112 and each operating position, the water stopcock 20 is in the open position between the cam positions 2 to 4 and the water stopcock 20.
The automatic water pressure valve 70 is opened, and when water is discharged, the number of gas seals is two, that is, the device stopper 76 and the magnet safety valve 74.

When the magnet safety valve and the igniter are de-energized and the motor is driven, the cam position 2
3, the magnet safety valve 74 is further connected to the cam positions 3 to 4
In this case, since the instrument plugs 76 are opened and the number of the gas seal portions is one, in the unlikely event that the instrument plug 76 or the magnet safety valve 74 fails, gas leakage will occur. According to the flowchart shown in FIG. 5 described above, when the dry battery is inserted or the power is turned on, the cam position is returned to the origin when the previous position is a position other than the origin. It is excluded.

Although various embodiments have been described above, in short, the present invention provides a magnet safety valve for a gas stopper when an overload abnormality, a motor lock, or the like occurs, or when the motor rotation position cannot be known due to a switch failure or the like. The motor is stopped at the position where the instrument plug is closed to prevent gas leakage from the gas burner. In addition, when the water heater is restarted after replacing the dry batteries, the origin check is performed to ensure normal operation from the opening of the water stop cock to combustion or fire extinguishing. . Therefore, it is needless to say that the present invention is not limited to the above embodiments and various modifications can be made without departing from the spirit of the present invention.

[0063]

As is apparent from the above description, according to the water heater of the present invention, when a motor overload abnormality, a micro switch failure, or the like occurs, a magnet safety valve or a gas stopper of a gas supply plug. Since the motor is stopped securely at the closed position, the leak of the raw gas from the gas burner does not occur at the time of these troubles and the safety in using the water heater is secured. It is a thing. Further, there is an advantage that the motor is not left energized, the battery is not wasted, and the service life of the dry battery can be extended. Furthermore, after the motor overload abnormality and the micro switch failure have been resolved or the consumable battery has been replaced with a new dry battery, normal operation is restarted by checking the origin of the motor stop position when the trouble occurs. Since it is a thing, it is extremely convenient.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a main stopper type water heater as an embodiment of the present invention.

2 is a timing chart (in a state where only a motor is turned on) showing a relationship between a rotation angle of a motor cam of the water heater shown in FIG. 1 and each operation.

FIG. 3 is a diagram showing a sequence flow when a motor overload abnormality or a micro switch failure occurs in this embodiment.

FIG. 4 is a flowchart showing the sequence flow shown in FIG.

FIG. 5 is a flow chart for explaining control of an origin (motor stop position) check in this embodiment.

FIG. 6 is a timing chart that clearly shows the relationship between the position of the motor cam and each operation in this embodiment in the description of the origin check control.

FIG. 7 is a schematic diagram showing a conventional motor drive type water heater for driving a motor and opening / closing a water stopcock or a gas stopcock;
It is a figure which showed notionally the relationship with the flow of a series of systems, such as combustion and stop.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 original stop type water heater 12 heat exchanger 14 gas burner 16 water supply pipe 18 hot water supply pipe 20 water supply stopcock 24 gas supply stopper 70 automatic water pressure valve 74 magnet safety valve 76 instrument stopper 110 first cam switch 112 second cam switch 116 ignition switch

【table】

Claims (2)

[Claims] 1. A heat exchanger provided with a water supply pipe or a hot water discharge pipe, a water shutoff plug provided in the water supply pipe or the hot water discharge pipe, a burner for heating the heat exchanger, and a burner connected to the burner. A gas supply plug including a magnet safety valve and a device stopper, a motor connected to the magnet safety valve of the water stopcock and the gas supply stopper and a device stopper, an ignition switch for turning the motor ON / OFF, and the gas supply unit. The rotational position of the motor is detected by a combination of a plurality of detection switches for detecting the opening / closing of the water stopper and the opening / closing positions of the magnet safety valve of the gas supply stopper and the instrument stopper, and ON / OFF signals from the plurality of detection switches. A signal from at least one of the plurality of detection switches is not input within a predetermined time by the motor position detection means and the detection signal from the motor position detection means. 2. A valve control device for a water heater, comprising: a motor stop position control means for controlling the motor so that the motor is stopped at a position where the magnet safety valve of the gas supply plug and / or the device plug is closed. 2. The origin position check means according to claim 1, further comprising an origin position check means for checking the origin position of the motor when the motor stopped by the control of the motor stop position control means is re-driven. Valve control device for water heater.