JP3370858B2 - Burner control device for vaporized oil combustor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a burner control device for a gas-fired oil combustor provided with a gas-heater constituting a combustion section of a water heater or the like. is there. 2. Description of the Related Art Conventionally, in this kind, as disclosed in, for example, Japanese Patent Application Laid-Open No. Hei 8-21606,
The amount of combustion in the burner section is increased or decreased by varying the amount of fuel and combustion air. By controlling the rotation speed of the combustion fan and using a damper to adjust the amount of combustion air, the amount of combustion adjustment can be controlled. Was able to be greatly expanded. [0003] In this conventional device, since it is installed outdoors or exhausts exhaust gas to the outside,
Exhaust air cannot be exhausted due to headwind or strong wind, and the amount of combustion air cannot be extremely reduced due to wind resistance, which causes backflow and misfire. Was limited. In order to solve this problem, in a water heater or the like, the amount of combustion is fixed, and ON / OF where combustion and combustion stop are repeated.
It is conceivable to perform the F combustion to obtain the required amount of heat. However, in the case of the vaporization method, the heat of the vaporizer is turned off when the burner section is turned off.
The problem is that good combustion cannot be obtained by ON / OFF combustion if the set temperature of the carburetor is not changed because the heat cannot be removed and the heat of the carburetor is taken away at the time of ignition. It had the following. The present invention focuses on this point and solves the above-mentioned drawbacks.
A vaporizer, which is provided with a vaporizer and a vaporization temperature sensor and is heated to a set temperature to vaporize fuel oil; and a burner portion which communicates with the vaporizer and premixes and vaporizes vaporized gas and combustion air. A heater control circuit for controlling the energization of the vaporization heater in accordance with the temperature detected by the sensor to maintain the vaporizer at a set temperature at which fuel oil can be vaporized. a proportional combustion to control the combustion amount by increasing or decreasing the this
In those with combustion determination means to perform a fixed ON / OFF burning the combustion amount to a minimum combustion amount less combustion amount of the proportional combustion, the combustion determination means, wherein the heat - held by motor control circuit ON / OFF of the set temperature of the vaporizer
During combustion, the temperature is shifted to a higher temperature side than during proportional combustion. In response to the heat demand due to the opening of the hot water tap 4, the combustion determining means 20 instantaneously calculates the required heat quantity from the tapping temperature and the set temperature, and calculates the heat quantity and a predetermined reference heat quantity. In comparison, if the required calorific value is more than this reference calorie,
The control of the burner section 3 is proportional combustion in which the amount of combustion is increased or decreased. On the other hand, when the amount of heat is less than the reference amount of heat, ON / OFF combustion with a fixed amount of combustion is performed.
It supplies the required amount of heat. At this time, the heater control circuit 17 receives the combustion judgment signal from the combustion judgment means 20, and holds the carburetor 5 at a normal set temperature in proportional combustion, and more than normal in ON / OFF combustion. The vaporizer 5 is maintained at a temperature shifted to a high temperature side by ten degrees. Therefore, in a situation where the heat back of the carburetor 5 cannot be sufficiently obtained by ON / OFF combustion, the control temperature of the carburetor 5 itself is increased.
Good combustion can be obtained by low vaporization, and a wide combustion control range can be obtained by setting the small heating power side to ON / OFF combustion. Next, a burner control device according to the present invention will be described with reference to an embodiment shown in the drawings. Reference numeral 1 denotes a heat exchanger provided in the middle of the hot water supply passage 2, which is heated by the combustion of a burner portion 3 located below, and appropriately supplies hot water by opening a hot water tap 4 provided at the end of the hot water supply passage 2. It is. Reference numeral 5 denotes a vaporizer provided with a vaporization heater 6 and a vaporization temperature sensor 7. The vaporizer is heated to a set temperature, which is a temperature at which fuel oil can be vaporized, and this temperature is maintained, and the vaporized gas and the combustion air are premixed. This is burned in the burner section 3. Reference numeral 8 denotes a combustion fan for supplying primary air for premixing to the carburetor 5 via the air passage 9 and secondary air for combustion to the burner section 3, respectively. The air flowing in from the formed combustion air intake 11 is sucked in from the air inlet 12 and supplied to each part. Reference numeral 13 denotes an exhaust port for discharging exhaust gas after heat exchange, and an exhaust path 14 provided with the heat exchanger 1 and the burner section 3.
Is in communication with Reference numeral 15 denotes a running water sensor provided in the hot water supply passage 2 on the upstream side of the heat exchanger 1, which detects a predetermined amount of flowing water due to the opening of the hot water tap 4 and outputs a signal indicating that there is a heat request. is there. Reference numeral 16 denotes a tap water temperature sensor provided in the hot water supply path 2 between the heat exchanger 1 and the hot water tap 4 for detecting the tap water temperature. Reference numeral 17 denotes a heater control circuit for controlling the energization of the vaporization heater 6, and a vaporizer 5 via a vaporization temperature sensor 7.
Is detected, and the vaporizer 5 is maintained at a predetermined vaporizable temperature. Reference numeral 18 denotes a standby circuit for setting the vaporizer 5 to a standby state in which the vaporizer 5 is maintained at a vaporizable temperature for a certain period of time before the start of combustion.
In response to the signal, one-hour counting is started, and a drive signal is output to the heater control circuit 17 until the count-up. In response to the detection signal of the flowing water sensor 15, the timer is reset, and after the heat request, one hour is extended,
This is sequentially continued, that is, the standby state is released only when there is no heat request for one hour. The reference numeral 20 compares the desired temperature from the hot water temperature setting means 21 for setting the desired hot water temperature with the detected temperature from the hot water temperature sensor 16 to calculate a necessary heat quantity. The combustion determining means for determining whether the combustion is OFF combustion outputs the result of the determination to the heater control circuit 17, thereby shifting the set temperature of the carburetor 5 to a higher temperature by several tens of degrees during ON / OFF combustion. In addition, the drive of the electromagnetic pump 22 for supplying fuel oil and the drive of the combustion fan 8 are controlled in accordance with the required amount of heat. [0018] 23 heat - the combustion control circuit including a motor control circuit 17 and the combustion determination means 20 is composed of a single microcomputer having various functions, such as comparison, operation timer igniter (not shown), such as While controlling other drive parts,
Each part can be controlled via a heater control circuit 17 and combustion determination means 20. Reference numeral 24 denotes a preheating indicator which is turned on during preheating of the vaporizer 5 and indicates that the standby circuit 18 is preheating. Next, the operation of this embodiment will be described with reference to the flowchart of FIG. In step 25, the carburetor 5 is set to a standby mode during preheating by the standby circuit 18 to be in a heat request standby state in which combustion can be started at any time. Then, in step 26, it is determined whether or not there is a heat request.
The ON signal of the running water sensor 15 when the hot water tap 4 is opened
If there is an S heat request, the process proceeds to step 27. In step 27, the vaporization heater 6 in the ON or OFF state is forcibly turned on during preheating, and then in step 28, it is ignited and the combustion of the burner section 3 is started. By forcibly turning on the heater 6, the temperature of the carburetor 5 is prevented from dropping at the start of the supply of fuel oil and combustion air at the time of ignition, and good ignition is performed. Then, the process proceeds to a step 29, wherein the hot water temperature setting means 21
The combustion determination means 20 calculates the required heat quantity from the difference between the target temperature of the hot water and the temperature detected by the tapping temperature sensor 16 and compares the required heat quantity with the reference heat quantity. Then, the process proceeds to step 30 to control the driving of the electromagnetic pump 22 and the combustion fan 8 in accordance with the required amount of heat in the continuous combustion to cause proportional combustion, and for example, dropping into a bath or hot water supply to a maximum of 40,000 to 6,800.
Even when a large caloric value of Kcal / h is required, hot water at the desired temperature can be obtained. At this time, the set temperature of the vaporizer 5 is set at step 31 at 225.degree.
The heater control circuit 17 controls the temperature at 5 ° C OFF. On the other hand, if the required heat amount is less than the reference heat amount in step 29, the process proceeds to step 32 with NO, and
0 controls the electromagnetic pump 22, the combustion fan 8, the combustion control circuit 23, and the like to fix the combustion amount and turn on / off the combustion.
By changing the ON time of F, O
The burner unit 3 is caused to perform N / OFF combustion.
Even when a small amount of heat of less than 3000 to 6800 Kcal / h is required, hot water supply at a desired temperature can be obtained. Further, ON / OFF from the combustion judging means 20
By inputting the combustion determination signal to the heater control circuit 17,
In step 33, the heater control circuit 17 shifts the set temperature of the vaporizer 5 to a higher temperature side than usual, and raises the temperature by 25 ° C. and controls 250 ° C. ON and 260 ° C. OFF. After steps 31 and 33, the process proceeds to step 34, where a request for heat is determined again. When the hot water supply is continued, there is a heat request. If YES, the process returns to step 29 to repeat the above operation. The required amount of heat in step 29 changes every moment because the heat exchanger 1 is gradually heated by continuing the combustion. Further, when the hot water supply is stopped, there is no heat request and the result is NO, and the routine proceeds to step 35, where the set temperature of the carburetor 5 is shifted to a higher temperature side by ON / OFF combustion.
After returning to the original normal set temperature, the flow returns to step 26 to wait for a heat request in the standby mode. Therefore, when the required heat quantity is small, ON /
Since OFF combustion is used, the range of adjustment of combustion can be greatly increased.
Since the set temperature is shifted to a higher temperature side than usual, a problem that abnormal combustion due to insufficient vaporization due to insufficient heat-back and insufficient vaporization is reliably prevented, and good combustion is always obtained. is there. In summary, the present invention provides a vaporizer which is provided with a vaporization heater and a vaporization temperature sensor and is heated to a set temperature to vaporize fuel oil, and communicates with the vaporizer to form vaporized gas and combustion air. A heater control circuit that includes a burner section for premixing and burning, and further controls the energization of the vaporization heater according to the temperature detected by the vaporization temperature sensor to maintain the vaporizer at a set temperature at which fuel oil can be vaporized. Proportional combustion in which the amount of fuel and the amount of combustion air are increased or decreased in accordance with the required amount of heat to control the amount of combustion, and this proportional combustion
Minimum combustion amount following combustion to secure the combustion amount in the amount ON of /
In a combustion engine having combustion determination means for performing OFF combustion, the combustion determination means determines the set temperature of the carburetor held by the heater control circuit during ON / OFF combustion and during proportional combustion. Since the temperature is shifted to a higher temperature side, a wide combustion control can be obtained by proportional combustion and ON / OFF combustion, and sufficient heat in ON / OFF combustion can be obtained despite the vaporization type having a vaporizer. -To reliably prevent a problem that abnormal combustion due to insufficient vaporization is not obtained due to insufficient amount of combustion, so that good combustion can always be performed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram of a water heater provided with a burner control device according to one embodiment of the present invention. FIG. 2 is a block diagram of the electric circuit. FIG. 3 is a flowchart of the main part. [Description of Signs] 3 Burner section 5 Vaporizer 6 Vaporizer 7 Vaporization temperature sensor 17 Heater control circuit 20 Combustion determination means

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-1-208617 (JP, A) JP-A-4-48147 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F23N 5/02 342 F24H 1/10 301

Claims (1)

(57) [Claim 1] A vaporizer which is provided with a vaporization heater and a vaporization temperature sensor and is heated to a set temperature to vaporize fuel oil, and communicates with the vaporizer to form a vaporized gas and combustion air. Control to keep the carburetor at a set temperature at which fuel vaporization is possible by energizing the vaporization heater in accordance with the temperature detected by the vaporization temperature sensor. and a circuit, a proportional combustion to control the combustion amount by increasing or decreasing the combustion air quantity fuel quantity on demand heat, minimum combustion amount following combustion of the proportional combustion
In those with combustion determination means for causing the ON / OFF combustion to burn amount to secure the combustion amount, the combustion determination means, wherein the heat - setting temperature of the vaporizer which is held by motor control circuit A burner control device for a vaporized oil combustor characterized in that during ON / OFF combustion, the temperature is shifted to a higher temperature side than during proportional combustion.