JP6976904B2 - Combustion device - Google Patents

Description

The present invention relates to a combustion device provided with a leveler tank that keeps the oil level constant.

Conventionally, in this type of combustion device, as disclosed in Patent Document 1, a leveler tank that receives fuel from an external tank and keeps the fuel level constant, and a leveler tank that is provided in the leveler tank and has an oil level in the leveler tank. Between the float valve and the external tank, a float valve that opens the fuel supply path when the fuel level drops below the specified oil level and closes when the fuel level rises above the specified oil level, an oil level sensor that detects the oil level in the leveler tank, and It is equipped with a shut-off valve that closes the fuel oil supply path from the external tank, a fuel pump that supplies the fuel oil of the leveler tank to the combustion section, and a control section that controls to open the shut-off valve during combustion operation. When an abnormality occurred in the float valve, there was an attempt to close the shutoff valve to prevent the overflow of fuel oil from the leveler tank.

Japanese Unexamined Patent Publication No. 2002-257336

However, in this conventional case, if a fine foreign substance is caught in the shutoff valve, a slow leak occurs in which the fuel oil continues to be supplied to the leveler tank little by little, and there is a risk that the fuel oil will eventually continue to overflow from the leveler tank. was there.

Therefore, in order to solve the above problems, the present invention comprises a leveler tank that receives fuel from an external tank and stores the fuel oil, an oil level sensor that detects the oil level in the leveler tank, and the external tank. It includes a shutoff valve that closes the fuel oil supply path, a fuel pump that supplies the fuel oil of the leveler tank to the combustion section, and a control section that controls the shutoff valve, and the control section closes the shutoff valve. When the oil level sensor detects a predetermined high oil surface in the state, after opening the closure valve period of time, and so as to close the shutoff valve.

Further, the plunger pump for supplying the fuel oil of the external tank is provided in the leveler tank, and the shutoff valve is provided on the discharge side in the plunger pump so as to close the valve when the plunger pump is stopped and open the valve when the plunger pump is driven. I made it.

Further, the shutoff valve is assumed to be composed of a valve seat provided on the discharge side of the cylinder of the plunger pump and a valve body provided on the discharge side end of the plunger of the plunger pump.

Further, a display unit for displaying an error is provided, and when the oil level sensor detects the predetermined high oil level, the control unit displays an error on the display unit and prohibits combustion in the combustion unit. I did it.

Further, the control unit cancels the display of the error and the prohibition of combustion when the oil level sensor detects a predetermined low oil level after the display of the error.

Further, a lower saucer for receiving the overflowing fuel oil was provided at the lower part of the leveler tank, and the volume of the lower saucer was set to a volume larger than the supply amount of the fuel oil when the shutoff valve was opened for a certain period of time.

According to the present invention, when a slow leak occurs in which a minute foreign substance is caught in the shutoff valve and a minute amount of fuel leaks, the slow leak progresses and the oil level in the leveler tank rises to a high oil level. This is detected by the oil level sensor, and the control unit forcibly opens the shutoff valve and eliminates the slow leak by flushing away the foreign matter that has been caught in the shutoff valve by the flow of fuel oil from the external tank, and then the shutoff valve. By closing, it is possible to prevent the fuel oil from continuing to overflow.

In addition, since the fuel oil is supplied to the leveler tank by the plunger pump, the restriction on the installation height of the external tank can be greatly relaxed, and the shutoff valve can be integrated into the plunger pump to reduce the cost. Further, when the shutoff valve is open, the reciprocating motion of the plunger causes a large flow rate of the fuel oil and can give a pulsation, so that foreign matter can be easily washed away.

In addition, it is not necessary to provide an electromagnetic coil just for opening and closing the shutoff valve, which makes it possible to further reduce the cost.

In addition, it is possible to notify the user or the like of the possibility that an abnormality has occurred and the fuel has leaked, and safety can be ensured by prohibiting combustion.

In addition, until it is confirmed by inspection etc. that there is no problem and the oil level in the leveler tank drops to the normal constant oil level, the error display and combustion prohibition will not be canceled, so safety is ensured and the fuel level is reduced. There is no fear of overflow.

In addition, even if the fuel oil overflows from the leveler tank by detecting the high oil level and opening the shutoff valve, the fuel oil does not overflow from the lower tray, so it is possible to prevent the fuel from polluting the installation location of the combustion device.

Schematic block diagram of one embodiment of the present invention Sectional drawing of the plunger pump of the same embodiment Flow chart explaining the operation of the same embodiment Configuration diagram of the main part of another embodiment

Next, the heater 1 which is an embodiment of the combustion device of the present invention will be described with reference to the drawings.
Reference numeral 2 is a housing of the heater 1, 3 is a bottom plate of the housing 2, and 2 is a shallow container-shaped lower tray having a rising portion 3a on the peripheral edge, and 4 is an operation panel having a display portion 4a and an operation switch 4b. Is.

5 is a combustion unit that burns fuel oil such as kerosene, 6 is a fuel supply device that supplies fuel oil to the combustion unit 5, 7 is a combustion fan that supplies combustion air taken in from the outside to the combustion unit 5, and 8 is the combustion unit 5. An ignition device having a spark rod for blowing sparks for ignition, and 9 is a flame detection device having a frame rod for detecting the presence or absence of a flame in the combustion unit 5.

Reference numeral 10 is a combustion cylinder in which the burner head 5a on which the flame of the combustion portion 5 is formed faces and forms a combustion chamber 10a. A red heat cylinder, 12 is a heat exchanger formed on the upper part of the combustion cylinder 10 to exchange heat between combustion heat and indoor air, and 13 is an exhaust cylinder for discharging the combustion exhaust gas after heat dissipation to the outside by the heat exchanger 12. Reference numeral 14 is a blower fan that blows indoor air to the heat exchanger 12.

Next, the fuel supply device 6 will be described in detail.
The fuel supply device 6 detects the leveler tank 15 for storing the fuel oil supplied to the combustion unit 5, the fuel pump 16 for supplying the fuel oil of the leveler tank 15 to the combustion unit 5, and the oil level height of the fuel oil in the leveler tank 15. It includes an oil level sensor 17 and a plunger pump 18 that supplies fuel pumped from an outdoor external tank (not shown) to a predetermined height when the oil level in the leveler tank 15 drops below a predetermined height.

The leveler tank 15 is arranged on the lower tray 3, and the upper surface of the leveler tank 15 is closed with a tank lid, and the fuel pump 16 and the oil level sensor 17 are attached to the tank lid. In the fuel pump 16, a suction end 16a is provided in the leveler tank 15, and fuel oil in the leveler tank 15 is supplied to the combustion unit 5 via the fuel pipe 19 in an amount corresponding to the amount of combustion.

The oil level sensor 17 is provided with a float 17b having a magnet that can move up and down on the support column 17a, and a low oil level reed switch 17c for detecting a predetermined low oil level in the support column 17a, and a predetermined oil level sensor 17. A high oil level reed switch 17d for detecting a high oil level is provided. Here, the predetermined low oil level is the lower limit oil level of the constant oil level maintained by the leveler tank 15, and the predetermined high oil level is the oil level higher than the upper limit oil level of the constant oil level maintained by the leveler tank 15.

In the plunger pump 18, the end on the discharge side is connected to the leveler tank 15 via the supply pipe 20, and the end on the suction side is connected to the oil supply pipe 21 for supplying fuel oil from an external tank installed outdoors. By operating, fuel oil is supplied from the external tank into the leveler tank 15, and by stopping, the fuel oil from the external tank is closed so as not to be supplied into the leveler tank 15. Further, since the plunger pump 18 is used as a mechanism for supplying fuel to the leveler tank 15, the limitation on the height difference between the external tank and the leveler tank 15 (the limitation on the installation height of the external tank) can be significantly relaxed.

Next, the plunger pump 18 will be described in detail with reference to FIG.
The plunger pump 18 is provided on a cylindrical cylinder 22, a plunger 23 reciprocally supported in the cylinder 22, a plunger spring 24 for urging the plunger 23 in the discharge direction, and an outer periphery of the cylinder 22. An electromagnetic coil 25 is provided.

The plunger 23 has a hollow cylindrical shape, and a suction valve seat 26, a suction valve 27, and a suction valve spring 28 for urging the suction valve 27 in the suction direction are provided in the lower portion thereof, and the plunger 23 is provided at the upper end of the plunger 23. A shutoff valve 29 (valve body) having a path communicating with the space inside the cylinder 22 in the radial direction is fixed.

A shutoff valve seat 30, a discharge valve seat 31, a discharge valve 32, and a discharge valve spring 33 for urging the discharge valve 32 in the suction direction are provided at the upper end of the cylinder 22, and the lower end of the cylinder 22 is provided with a discharge valve spring 33. A filter 34 is provided.

Then, when the electromagnetic coil 25 is intermittently excited at a predetermined on-time and a predetermined frequency by the drive command of the plunger pump 18, the plunger 23 closes the shutoff valve 29 due to the magnetic flux at the time of energization from the stop position. It is pulled downward in the figure against the urging force of the plunger spring 24, at which time the suction valve 27 opens, the discharge valve 32 closes, and the shutoff valve 29 integrated with the plunger 23 opens. Then, the fuel is moved from the lower space of the cylinder 22 with the plunger 23 as a boundary to the upper space.

Next, when the magnetic flux disappears when the electromagnetic coil 25 is not energized, the plunger 23 rises upward in the figure due to the urging force of the plunger spring 24, and at that time, the suction valve 27 closes, the discharge valve 32 opens, and the plunger opens. The fuel oil in the upper space of 23 is discharged to the supply pipe 20, and the fuel oil from the oil supply pipe 21 is sucked into the lower space.

Then, the electromagnetic coil 25 is energized before the plunger 23 reaches the stop position to supply fuel oil from the external tank to the leveler tank 15, and when the drive command of the plunger pump 18 disappears, the electromagnetic coil 25 is stopped. , The plunger 23 stops at the stop position.

In this way, since the shutoff valve 29 is integrated with the plunger 23 and is urged in the discharge direction by the plunger spring 24, even if pressure is applied from the external tank, the shutoff valve 29 reliably closes the shutoff valve 29 from the leveler tank 15. It is possible to prevent the overflow of fuel oil, and since the electromagnetic coil 25 that opens and closes the shutoff valve 29 is also used to reciprocate the plunger 23, a coil only for opening and closing the shutoff valve 29 is unnecessary and the cost is low. It can be transformed into.

Next, reference numeral 35 denotes a control unit for controlling the heater 1, which includes a microcomputer in which a program is stored in advance, and outputs detection values of various sensors such as the flame detection device 9 and the oil level sensor 17 and output of the operation switch 4b. Is input to control the operation of the display unit 4a, the combustion fan 7, the ignition device 8, the blower fan 14, the fuel pump 16, and the plunger pump 18.

Then, when the operation switch 4b is operated and an instruction to start the heating operation is given, the control unit 35 drives the fuel pump 16, the combustion fan 7, and the blower fan 14, and the fuel oil from the fuel supply device 6 and the combustion fan 7 are driven. The combustion air from the combustion unit 5 is supplied to the combustion unit 5, drives the ignition device 8 to start combustion, and the combustion gas from the combustion unit 5 is heat-exchanged with the indoor air by the heat exchanger 12 to become combustion exhaust gas. While the indoor air is discharged to the outside through the exhaust pipe 13, the indoor air is heated by the heat exchanger 12 by the blower fan 14 and blown out from the warm air outlet (not shown) for heating.

In the fuel supply device 6, when the oil level drops during the heating operation and the low oil level reed switch 17c detects the magnet of the float 17b, the control unit 35 starts driving the plunger pump 18 and starts time counting. When a predetermined time elapses, the drive of the plunger pump 18 is stopped so that the inside of the leveler tank 15 is kept at a constant oil level. Here, the control unit 35 constantly monitors the output of the oil level sensor 17 regardless of whether the heating operation is in operation or stopped.

When the operation switch 4b is operated and an instruction to stop the heating operation is given, the control unit 35 stops the fuel pump 16 and the combustion fan 7 to stop the combustion, and then re-drives the combustion fan 7 and determines the predetermined value. The driving of the combustion fan 7 and the blower fan 14 is continued until the time elapses, and when the inside of the machine is cooled, the drive of the combustion fan 7 and the blower fan 14 is stopped to end the operation.

Next, the characteristic operation of the present invention will be described with reference to the flowchart of FIG.
In the unlikely event that a minute foreign substance is caught between the shutoff valve 29 and the shutoff valve seat 30 of the plunger pump 18 for some reason and a closing failure occurs in the shutoff valve 29, the external tank is at a higher position than the leveler tank 15. In this case, a slow leak will occur in which the fuel oil continues to be supplied to the leveler tank 15 through the gaps between the foreign substances.

When the control unit 35 detects that a slow leak occurs and the oil level in the leveler tank 15 slowly rises, and the float 17b rises to the height of the high oil level reed switch 17d as the oil level rises (in step S1). Yes), then it is determined whether the combustion operation is in progress due to heating operation or the like (step S2).

If the combustion operation is in progress (Yes in step S2), the control unit 35 stops combustion (step S3), stores in the microcomputer that the subsequent combustion operation is prohibited (step S4), and fuel oil from the leveler tank 15. Proceed to the next step while ensuring safety against overflow, and if the combustion operation is not in progress, proceed to the next step via step S4. It is determined whether or not the error of is displayed on the display unit 4a (step S5).

If no other error is displayed (Yes in step S5), an error indicating that the oil level in the leveler tank 15 has risen abnormally is displayed on the display unit 4a (step S6). At this time, it is preferable to generate a notification sound at the same time. By displaying the error indicating that the oil level has risen abnormally in this way, it is possible to notify the user or the like that an abnormality has occurred and the fuel oil may have leaked.

On the other hand, if another error is displayed (No in step S5), the process proceeds to the next step while continuing to display the other error that has already occurred. The other error is an error other than the error that the oil level has risen abnormally, and is an error that causes combustion to stop. As a result, it is possible to know that an abnormality that stops combustion has occurred prior to the error that the oil level has risen abnormally, and the user can take appropriate measures.

Then, the control unit 35 stores in the error storage unit in the microcomputer that an error that the oil level has risen abnormally has occurred (step S7), and prepares for information transmission to the repair company later. ..

Next, the control unit 35 starts driving the plunger pump 18 and puts the closing valve 29, which seems to be biting a foreign substance, into a valve open state (step S8). When the shutoff valve 29 is opened, the foreign matter caught in the shutoff valve 29 is washed away by the flow of fuel oil from the external tank.

At this time, since the plunger 23 is reciprocated with the shutoff valve 29 open, the fuel oil flows at a large flow rate by the plunger pump 18, and further, the pulsation accompanying the reciprocating movement of the plunger 23 is added, and the shutoff valve 29 is added. Alternatively, fine foreign matter that may have adhered to the shutoff valve seat 30 can be reliably washed away.

Then, when a certain period of time of about several seconds has elapsed from the start of driving the plunger pump 18 (Yes in step S9), the control unit 35 stops the energization of the electromagnetic coil 25, stops driving the plunger pump 18, and closes the valve 29. Close (step S10). In this way, it is possible to return to the state in which the slow leak at the shutoff valve 29 is eliminated and prevent the fuel oil from continuing to overflow.

Here, the amount of fuel supplied in a certain period of time (step S9) for driving the plunger pump 18 to eliminate the slow leak is set sufficiently smaller than the capacity of the lower tray 3 in which the leveler tank 15 is installed. Even if the fuel oil overflows from the leveler tank 15 by driving the plunger pump 18 for a certain period of time, the fuel oil does not overflow to the outside of the lower tray 3, so that the place where the heater 1 is installed can be prevented from being contaminated by the fuel oil. ..

Then, the cause of foreign matter flowing into the plunger pump 18 is removed by inspection by a contractor based on the request of the user, and the oil level in the leveler tank 15 is lowered to a normal constant oil level lower than a predetermined high oil level. Then, the control means 35 confirms that the high oil level reed switch 17d does not detect, hides the error indicating that the oil level has risen abnormally, cancels the combustion prohibition measure, and returns to the normal state. I am trying to restore it. The error display may be hidden when the operation switch 4b is operated by the user.

Here, since the combustion prohibition measure is continued until the high oil level reed switch 17d is no longer detected, combustion does not occur in the middle of an abnormal state, and safety can be ensured more reliably. ..

The drive of the plunger pump 18 in step S8 may be different from the drive in the normal state. By making the excitation off time of the electromagnetic coil 25 longer than usual, the shutoff valve 29 can be hit against the shutoff valve seat 30, the excitation frequency can be increased, or the ontime can be lengthened to increase the flow rate and cause more foreign matter. May be made easier to flow away.

Next, another embodiment of the present invention will be described with reference to FIG. In this other embodiment, the fuel supply device 6 is changed from the pumping pump system to the float valve system, and the same configuration as that of the previous embodiment is designated by the same reference numerals and the description thereof will be omitted.

In this fuel supply device 6, a float valve 36 is provided in the leveler tank 15, and a solenoid valve 37 as a shutoff valve of the present invention is provided in the middle of the inflow path to the float valve 36.

The float valve 36 includes a float 38 that moves up and down as the oil level rises and falls, and an on-off valve body 40 that closes a valve hole opened at the upper end of an inflow cylinder 39 having a valve hole at the upper end via an arm 41. It is rotatably attached by a support shaft 42.

Then, when the oil level in the leveler tank 15 is lowered by the drive of the fuel pump 16, the float 38 is also lowered accordingly, and the on-off valve body 40 on the opposite side of the support shaft 42 is raised, so that the valve hole is opened and the outside is opened. Fuel is supplied from the tank. When the oil level rises, the float 38 rises and the on-off valve body 40 on the opposite side of the support shaft 42 descends, so that the valve hole is closed and the oil level in the leveler tank 15 is kept constant.

As the oil level sensor 17, an optical sensor is used, and it is possible to detect that the oil level has risen abnormally to a predetermined high oil level and that the oil level has dropped to a predetermined constant oil level.

In a combustion device using such a float valve type fuel supply device 6, the control means 35 closes the solenoid valve 37 while the combustion operation is stopped, and when an abnormality occurs in the float valve 36. Although the overflow of the fuel oil is prevented, if the float valve 36 and the solenoid valve 37 have double closing defects, it is conceivable that the fuel oil overflows from the leveler tank 15.

Therefore, as in the present invention, when the oil level sensor 17 detects a predetermined high oil level, the solenoid valve 37 as a shutoff valve is opened for a certain period of time, so that the solenoid valve 37 is caught by the flow of fuel oil from the external tank. The slow leak can be eliminated by flushing away the foreign matter, and then the solenoid valve 37 can be closed to prevent the fuel oil from continuing to overflow.

The present invention is not limited to the above-described embodiment, and can be modified without changing the gist. The heater 1 has been described as an example, but for example, a heating boiler or a water heater. Is also good.

Further, although the lower tray 3 has been described so as to form the bottom plate of the housing 2, it may be used only for receiving the overflowing fuel oil independently of the housing 2.

3 Bottom pan 4a Display unit 5 Combustion unit 15 Leveler tank 16 Fuel pump 17 Oil level sensor 18 Plunger pump 22 Cylinder 23 Plunger 29 Closure valve 30 Closure valve seat 35 Control unit

Claims (6)

A leveler tank that receives fuel from an external tank and stores fuel, and a leveler tank that stores fuel.
An oil level sensor that detects the oil level in the leveler tank, and
A shutoff valve that closes the fuel supply path from the external tank,
A fuel pump that supplies the fuel oil of the leveler tank to the combustion unit,
A control unit for controlling the shutoff valve is provided.
Wherein the control unit, when the oil level sensor detects a predetermined high oil level in a state that closes the shut-off valve, after opening the closure valve period of time, that it has to be closed the shut-off valve Combustion device as a feature. A plunger pump for supplying fuel from the external tank is provided in the leveler tank.
The combustion device according to claim 1, wherein the shutoff valve is provided on the discharge side in the plunger pump, and is closed when the plunger pump is stopped and opened when the plunger pump is driven. 2. The invention according to claim 2, wherein the shutoff valve is composed of a valve seat provided on the discharge side of the cylinder of the plunger pump and a valve body provided on the discharge side end of the plunger of the plunger pump. Combustion device. A display unit that displays errors is provided.
The first aspect of the present invention is characterized in that, when the oil level sensor detects the predetermined high oil level, the control unit displays an error on the display unit and prohibits combustion in the combustion unit. The combustion apparatus according to any one of 3 to 3. The combustion device according to claim 4, wherein the control unit cancels the display of the error and the prohibition of the combustion when the oil level sensor detects a predetermined low oil level after the display of the error. A lower saucer for receiving the overflowing fuel is provided at the bottom of the leveler tank.
The combustion device according to any one of claims 1 to 5, wherein the volume of the lower saucer is set to a volume larger than the supply amount of fuel oil when the shutoff valve is opened for a certain period of time.

Images