JPS6237619A - Liquid fuel burner - Google Patents

Abstract

PURPOSE:To make it possible to burn a carburetor automatically without supply of fuel by detecting the conditions which require burning a carburetor in a burner without supply of fuel and stopping a fuel pump and a carburetor and, after a specified time has elapsed, holding the burning without supply of fuel at a specified temperature and for a specified time based on memory. CONSTITUTION:When tar is accumulated in a carburetor 4, the fuel flow resistance from the point 3 to the point 7 of a carburetor 3 increases and the amount of the vaporized gas decreases. The flame current that flows between a flame current detection electrode 15 and a burner 8 corresponding to the combustion heat quantity is outputted as flame current signal A by means of a flame current detection circuit 20. Flame current signal A is compared with pump output signal at a comparison circuit 21, and if the former is smaller than pump output signal B, instruction signal C of the combustion without fuel supply is outputted from the comparison circuit 21. After a predetermined time of combustion without fuel supply has passed, power cutting signal is sent to a heater control circuit 18 to cut off the electric current to the heater 5, but at the same time a memory-holding switch 22 is also opened and the memory of signal C of the combustion without fuel is erased,and the combustion device burner all returns to the stopping of the normal operation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a combustion device for α-form fuel (used for heating, etc.), and particularly to a vaporization type combustion device.

[Conventional technology] Liquid fuel such as kerosene is turned into vaporized gas in a vaporizer, and then jetted from a nozzle to obtain a mixed gas with air.

A device that burns with a burner is a public "fu".If altered fuel or fuel with a large amount of heavy components is used in such a combustion device, the heavy components will turn into tar and accumulate in the carburetor. This obstructs the flow of fuel, inhibits normal vaporization, and reduces fuel consumption.

Conventionally, when fuel consumption decreased due to tar accumulation, measures such as replacing the carburetor or disassembling it for cleaning were taken, but this resulted in a large two-hour and economic loss. On the other hand, there is also a method of stopping the combustion operation and burning the vaporizer at a higher temperature to decompose and remove residual tar that is not vaporized at normal vaporization temperatures, which is extremely effective in the early stages of tar accumulation. It is known.

When performing such a dry firing of the carburetor, the user discovers an abnormal drop in fuel droplets through observation of the combustion state, stops the combustion operation, and turns on the dry firing switch using a two-handed operation. There are methods, but it is difficult to detect combustion abnormalities unless you are an expert.

Therefore, there are methods such as installing a tar accumulation detection device and using a lamp to indicate the necessity of dry firing.

However, in all of these methods, the user has to wait for the timing to turn on the dry firing switch after stopping the combustion operation, and there is also the trouble of stopping the dry firing at a certain time.

Furthermore, if the timing of the dry firing is lost, the accumulation of tar may progress and the effect of the dry firing may not be sufficiently obtained, and there is an inconvenience that caution cannot be omitted regarding the operating condition.

[Problems to be Solved] Under the above-mentioned circumstances, the present invention saves the user's troubles and achieves long-life liquid fuel combustion by timely and automatically dry-burning the tar in the vaporizer. This is an attempt to realize a device.

[Means for Solving the Problems] In order to achieve the above objects, the liquid fuel combustion device of the present invention uses a fuel pump to feed liquid fuel into a vaporizer with a built-in electric heater to vaporize it, The mixed gas obtained by ejecting vaporized gas from a nozzle is guided to a burner and combusted, and it detects and stores when the combustion device reaches a state that requires dry firing of the vaporizer. After the oil pump and the vaporizer have stopped and a predetermined time has elapsed, the vaporizer is energized based on the above memory to reach the dry baking temperature and maintained for the predetermined dry baking time, and then the vaporizer is turned off at the same time. It is configured to erase the above memory and return to the normal combustion stop state.

The combustion device is equipped with a device that detects a drop in flame current with respect to the oil pump output or a device that integrates combustion operation time as a means of detecting whether or not the combustion device requires dry firing of the carburetor. By storing the detection result as a dry firing command signal, it is possible to eliminate the need for the user to judge whether dry firing is necessary or not.

That is, the present invention uses an oil pump to feed liquid fuel into a vaporizer with a built-in electric heater to vaporize it, and blows out the vaporized gas from a nozzle to lead the resulting air-mixed gas to a burner where it is combusted. The apparatus includes a storage means for storing a carburetor dry-burning command signal inputted by two people, and when combustion of the apparatus is stopped in a normal operation, the dry-burning command signal is read from the storage means and the dry-burning operation is started. an operation start means for issuing a command; a dry-burning operation control means for energizing the vaporizer after a predetermined period of time has elapsed after the command; holding the dry-burning temperature for a predetermined time and cutting off the electricity; The liquid fuel combustion device is a liquid fuel combustion device comprising a return means for erasing the memory of a burner command signal, and further includes a pump output signal conversion means for receiving a drive input signal of an oil feed pump and converting it into a pump output signal, and a burner control signal. Is the device equipped with flame current detection means that detects flame current and outputs a flame current signal, and signal comparison means that outputs a dry firing command signal when the flame current signal is smaller than the pump output signal, or is the operating time of the device A return function that includes an operation time accumulation means that outputs a dry-burning command signal when the accumulated value of the dry-burning reaches a predetermined value, and also has a function to return the accumulated value of operating hours to zero when the power is cut off after the dry-burning is completed. It is a liquid fuel combustion device equipped with

[Example] The first example of the configuration of the liquid fuel combustion apparatus of the present invention is as follows.
As shown in the figure.

The fuel in the oil tank (1) is sent to the carburetor (3) by the oil pump (2). The vaporizer (3) has a concentric annular cylindrical vaporization chamber (4) and is heated by a cylindrical heater (5). The temperature of the vaporizer (3) is determined by the temperature sensor (6)
By adjusting the power input to the heater (5) by the heater control circuit (18), the temperature is controlled in accordance with the amount of fuel fed. The fuel is stored in the vaporization chamber (4
) and is ejected from the nozzle (7) into the mixing tube (9) of the burner (8), mixed with air and then released into the crater (lO).
Burns in. (11) is a spark plug that uses high-pressure spark discharge. Note that (12) is a needle valve that is pulled by the solenoid (13) to open the nozzle (7) during combustion, but at other times it closes the nozzle (7) and is installed behind the solenoid (13). The relief valve (14) is opened to allow fuel in the vaporization chamber 4) to return to the oil tank.

By controlling the human power to drive the oil pump (2), the amount of oil fed can be adjusted appropriately, but if tar accumulates in the vaporization chamber (4), the flow from the vaporizer (3) to the nozzle (7) will be reduced. The resistance to fuel flow between the two areas increases.

Even if the drive input to the oil pump (2) is the same, the amount of vaporized gas decreases. Flame current detection electrode <I
5) and the burner (8) is output as a flame current signal A by the flame current detection circuit (20).On the other hand, the flame current flowing between the oil feed pump (2) and the burner (8) is output from the pump control circuit (19).
), and a pump output signal B obtained by performing frequency conversion from the drive input is output.

Here, the pump output signal is determined by a calculation device that is set in advance so that the value is smaller than the standard flame current signal value that is expected in response to the pump drive input when the combustion device is operating normally. The flame current signal A is output as a value corresponding to the pump drive input at any given time (Fig. 2).The flame current signal A is compared with the pump output signal B in the comparator circuit (21), and the pump output signal is When the dry firing command signal C is smaller than the signal B, the dry firing command signal C is output from the comparison circuit (21), and the dry firing operation control circuit (23) is maintained with the memory retention switch (22) turned on, so that the dry firing command signal C is ready to start operation at any time. is maintained. To stop the operation of this combustion equipment, 1. Normally, a manual operation such as pressing a fire extinguishing switch button is performed, but when the extinguishing switch is pressed, a start signal is activated in conjunction with the extinguishing signal to control dry firing operation. The heat is sent to the circuit (23), and a built-in timer starts operating, automatically executing dry firing. On the other hand, if there is no dry firing command signal C, the memory retention switch (22) will remember the off state, and even if there is a start signal, the dry firing operation control circuit (23) will not operate and the timer will start operating. After a predetermined time period sufficient to equalize the pressure in the system, the heater control circuit (18) is activated and the heater (5) is activated.
energized only. The vaporizer (3) is controlled to have a temperature of, for example, 400° C., and the tar accumulated in the vaporizer (3) is vaporized and collected from the relief valve (!4) into the oil tank (1).

After the preset dry firing time has elapsed, a power-off signal is sent to the heater control circuit (!8), and the heater (5) is turned off.
) is turned off, but at the same time, the memory retention switch (22) is also turned off, and the memory of the dry firing command signal C is erased. As a result,
In one example of the combustion apparatus, all the combustion apparatuses return to the normal operation stop state, and the dry firing operation control circuit (23) returns to the standby state.

After automatically running the dry firing operation in this way, you can return to the combustion operation at any time, but at this time, if the flame current signal A is within the normal range with respect to the pump output signal B, the combustion operation will continue. If the fire continues and does not return to the normal range, dry firing operation will be resumed after manual extinguishing.

2. Another embodiment of the liquid fuel combustion device of the present invention is shown in FIG.
Instead, an operating time integration circuit (17) is provided. In this example, while the combustion device is in operation, the operation time accumulation circuit (17) is configured to accumulate the operation time, and when the cumulative operation time reaches a predetermined fixed time, issue a dry firing command signal E. There is.

When the dry firing command signal is manually input to the memory retention switch 22), the memory retention switch (22) remains turned on and the dry firing operation control circuit (23) becomes the reservation letter 1 method.
When the combustion operation is then manually stopped, the built-in timer starts operating, and after a sufficient time has elapsed to equalize the pressure in the system, the heater control circuit (18) is activated and only the heater (5) is energized. be done.

From then on, the dry firing of the vaporizer (3) proceeds in the same manner as in the previous example, but at the same time as the heater (5) is cut off, the holding of the memory retention switch (22) is also cut off and reset, and the cumulative time release circuit is turned off. (16) cancels the accumulation of driving time. For this reason,
Thereafter, when the combustion operation is restarted, the operation time integration circuit (17) again integrates the operation time from zero. In addition, if the combustion operation is stopped due to the activation of a safety device for some reason, the dry firing operation control circuit (23) will stop the dry firing operation even if the cumulative operation time exceeds a predetermined period of time. The circuit is configured to prevent dry firing even after the firing command signal is issued.

[Effects of the Invention] As explained above, the liquid fuel combustion device of the present invention can automatically perform dry firing of the carburetor using a specific control means, and can perform dry firing without the user's intervention. From the beginning, even if a liquid fuel that has undergone some degree of deterioration is used, tar can be removed before it accumulates in the vaporization chamber (4), and combustion can be continued in the best condition at all times. It can also extend the lifespan of your combustion equipment. Since there is no need to interrupt the combustion operation to perform dry firing, the user is not forced to perform any troublesome operations.

[Brief explanation of the drawing]

1 and 3 are block diagrams of the liquid fuel combustion apparatus of the present invention. FIG. 1 is an embodiment in which dry firing is performed by detecting the flame current of the burner, and FIG. 2 is the same as that of FIG. 1. Graph showing the condition range in which the dry firing command signal is issued in the example, 3rd
The figure shows an example in which dry firing is performed by integrating the operating time. 3... Carburizer, 5... Heater, 16... Cumulative time release circuit, 17... Operating time integration circuit, 18.
...Heater control circuit, 19...Pump control circuit,
20...flame current detection circuit. 21... Comparison circuit, 22... Memory retention switch, 2
3...Dry firing operation control circuit. Patent applicant: Dainichi Kogyo Co., Ltd. Representative: Fumio Sasaki

Claims (3)

[Claims] (1) A device that uses an oil pump to feed liquid fuel into a vaporizer with a built-in electric heater, vaporizes it, and blows out vaporized gas from a nozzle to lead the resulting air-mixed gas to a burner and burn it. a storage means for storing the input carburetor dry-burning command signal; and an operation for reading out the dry-burning command signal from the storage means and instructing a dry-burning operation when combustion of the device is stopped in a normal operation. a start means, a dry firing operation control means for energizing the vaporizer after a predetermined period of time has elapsed after the command, maintaining the dry firing temperature for a predetermined period of time, and cutting off the electricity; and a return means for erasing the memory of the liquid fuel combustion device. (2) A device that uses an oil pump to feed liquid fuel into a vaporizer with a built-in electric heater, vaporizes it, and then blows vaporized gas out of a nozzle to lead the resulting air-mixed gas to a burner and burn it. a pump output converter that receives a drive input signal of the oil pump and converts it into a pump output signal; a flame current detector that detects a flame current of the burner and outputs a flame current signal; and a flame current detector that detects a flame current of the burner and outputs a flame current signal; a comparison means for outputting a dry firing command signal when the signal is smaller than the pump output signal; a storage means for storing the dry firing command signal; an operation start means for reading out the dry-burning command signal and commanding dry-burning operation; and a dry-burning device for energizing the vaporizer after a predetermined time has elapsed after the command, holding the dry-burning temperature for a predetermined time, and then turning off the power. A liquid fuel combustion device comprising an operation control means and a return means for erasing the memory of the dry firing command signal at the same time as the power is cut off. (3) A device that uses an oil pump to feed liquid fuel into a vaporizer with a built-in electric heater, vaporizes it, and blows out vaporized gas from a nozzle to lead the resulting air-mixed gas to a burner and burn it. an operating time integrating means for outputting a carburetor dry firing command signal when the cumulative value of the operating time of the apparatus reaches a predetermined value; a storage means for storing the dry firing command signal; operation start means for reading out the dry-burning command signal from the storage means and instructing dry-burning operation when the operation is performed; A liquid comprising: a dry-burning operation control means that holds the power for a predetermined period of time and then turns it off; and a return means that simultaneously erases the memory of the dry-burning command signal and returns the cumulative value of the operating time to zero. Fuel combustion equipment.