JPS6330034Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a combustion control device that controls a plurality of combustors, each of which can be controlled to blink independently.In particular, in the event of a misfire in any combustor, a timer circuit is used to control the combustion of all combustors. This is to stop the system and take complete control.

In devices such as gas hot water heaters and bathtubs with gas water heaters, which generally have multiple combustors housed in a single exterior case, if one of the combustors experiences abnormal combustion such as a misfire, It is preferable for safety to stop combustion in both combustors.

Therefore, the present invention was devised in view of the above points, and will be explained below first based on FIG. 1.

Reference numeral 1 denotes the main body of a bathtub with a gas water heater, in which a bath heat exchanger 3 and a water heater heat exchanger 4 are arranged side by side in an exterior case 2, and burner sets 5 and 6 are installed below these, respectively. It is set up. Further, exhaust guides 7 and 8 are connected above each of the heat exchangers 3 and 4, and the upper ends of these guides are opened in an exhaust top 9 attached to the upper part of the outer case 2. Further, the burner sets 5 and 6 are provided with first, second, third and fourth solenoid valves 11 and 1 which are operated by a control circuit 10.
2, 13, 14 interposed gas supply paths 15, 16
The spark plugs 17 and 18 for bath and hot water supply and flame detection rods 19 and 20, which are controlled in the same way, are connected to each other.

Reference numeral 21 denotes a water jacket that is integrally interposed in the heat exchanger 3 between a pair of upper and lower communication pipes 23 and 23' that communicate the bath heat exchanger 3 and the inside of the bathtub 22, and is used to connect the communication pipes 23 and 23'. It has a cylindrical shape slightly longer than its position, and houses therein a hot water temperature detection sensor 25, such as a plurality of diodes 24, 24, . . . connected thereto.

FIG. 2 is a circuit diagram showing the control circuit 10 mentioned above.
A bath control circuit 32 and a hot water supply control circuit 33 are connected in parallel to a low-voltage DC power supply 31 of about 30 V through a normally open push button switch 34 on one side and a well-known running water switch 35 on the other.

First, the bath control circuit 32 will be explained. Reference numerals 36 and 37 are first and second comparators constituting a safety timer 39 and a hold timer 40 that are connected to the rear stage of the push button switch 34 via a diode 38. The partial voltages 41, 42, 43 are connected to reference inputs 36', 37', and the outputs of an integrating circuit including resistors 44, 45 and capacitors 46, 47 are connected to comparison inputs 36'', 37''. Note that a diode 48 for blocking discharge of this capacitor is connected between the resistor 45 and the capacitor 47. Reference numeral 49 denotes a first switching element connected after the diode 38, and a transistor 50 connected to the output of the second comparator 37 is connected to the base, and after the push button switch 34 is closed, the capacitor 47 is connected to the reference input. 37' level is reached and the output of the second comparator 37 is inverted to low.

51 and 52 are the first and second solenoid valves 11 and 12;
A second switching element 54 whose base is connected to a transistor 53 connected between the pushbutton switch 34 and the diode 38 and connected to the output of the second comparator 37, and a first switching element 54 whose input is a CR timer etc. is an electromagnetic coil. The transistor 5 outputs the output of the third comparator 55 for forced ignition, which outputs a low level after the element 49 is turned on and reverses to a high level output after a predetermined time.
6. Transistors 58 and 59 connected via a diode 57 in a Darlington connection are connected in series. Therefore, the second and third comparators 37, 55
During the ignition operation due to the low output of
By turning on the second switching elements 49, 54 and the transistors 58, 59, the electromagnetic coil 51,
52 is energized, and the first and second solenoid valves 11 and 12 are opened. Note that 60 is a fourth comparator constituting a forced ignition timer similar to the third comparator 55 described above.

61 is a flame detection circuit using a pair of well-known FETs 62 and 63 configured after the first switching element 49; an ignition display circuit 67 consisting of a transistor 64, a resistor 65, and a light emitting diode 66 is connected to the output of one FET 63; In addition, the output of the other FET 62 is connected to the comparison input 36'' of the first comparator 36.
When a flame is detected by turning off FETs 62 and 63, the capacitor 46 is quickly charged and the first comparator 36
Flip to high. On the other hand, the output of the first comparator 36 is connected between the resistor 45 of the comparison input 37 of the second comparator 37 and the diode 48, but since the transistor 68 is turned on during the above operation, the output of the first comparator 36 is substantially Dropped to a low level, charging of the capacitor 47 is inhibited below the inversion level of the second comparator 37, and the second comparator 37 continues to output a low level. Reference numeral 69 denotes a self-holding relay in which a transistor 70 connected in series receives the output of the flame detection circuit 61, and its normally open contact 69' is connected in parallel to the push button switch 34 via a normally closed stop switch 71. ing. The output of the flame detection circuit 61 is also connected between the diode 57 and the transistor 58 via diodes 72 and 73, so that the presence of a flame can be detected even after the second comparator 37 has finished the timer. If done, transistor 5
8, 59 to turn on the first and second solenoid valves 11, 12.
Continue to open.

74 is the first switching element 49 as described above.
In the hot water temperature detection circuit configured in the latter stage, the hot water temperature detection sensor 2 whose voltage is made constant by the transistor 75
A fifth comparator 77 compares the output of sensor 24 with the output corresponding to the set temperature by variable resistor 76, and the output of this comparator is compared with the reference input by resistors 78 and 79 to determine whether the output of sensor 24 is When the output corresponding to the set temperature is reached and the fifth comparator 77 inverts its output to a high level, a sixth comparator 80 receives this and outputs a high level inverted output.
The output of the sixth comparator 80 is connected to the gate of the SCR 81 connected to the base of the first switching element 49, and when the water temperature in the bathtub 22 reaches the set temperature, the SCR 81 is turned on and the first switching element 49 is turned on. Turn off.

Next, the hot water supply control circuit 33 will be explained.
Reference numerals 90 and 91 denote seventh and eighth comparators constituting a safety timer 93 and a hold timer 94, which are connected downstream of the flushing water switch 35 via a diode 92 in the same way as for the bath, and are connected to resistors 95, 96, and 97. voltage to the reference inputs 90', 91', and resistor 9.
The outputs of the integrating circuit with 8,99 capacitors 100, 101 are connected to comparison inputs 90'', 91'', respectively. Note that a diode 102 for blocking discharge of this capacitor is connected between the resistor 99 and the capacitor 101. Reference numeral 103 denotes a third switching element connected after the diode 92, which is connected to the base of a transistor 104 connected to the output of the eighth comparator 91, and after the water flow switch 35 is closed, the output of the eighth comparator 91 is connected to the third switching element 103. is turned on until it flips to low. 105 and 106 are the third and fourth solenoid valves 1;
3 and 14 electromagnetic coils, a fourth switching element 108 whose base is connected to a transistor 107 connected between the running water switch 35 and the diode 92, and whose base is connected to the output of the eighth comparator 91;
A common integration circuit consisting of a resistor 109 and a capacitor 110 is connected to comparison inputs 111'' and 112'', and the output of one 112 of the 9th and 10th comparators 111 and 112 for forced ignition is connected to a Darlington-connected transistor, etc. The electromagnetic valve circuit 113 is connected in series. Also, the ninth and tenth comparators 11
1,112 reference inputs 111', 112' are connected to resistors 114, 115 partial pressure, and after the water flow switch 35 is closed, the high output of the eighth comparator 91 and the
10 When the comparator 112 has a high output, the third and fourth switching elements 103 and 108 are turned on, and the solenoid valve circuit 113 is activated to close the third and fourth solenoid valves 1.
Open 3,14.

116 is a flame detection circuit using a pair of FETs 117 and 118, and the output of 117 is sent to a seventh comparator 90.
and the other output is connected to the base of the transistor 119 connected to the output of the ninth and tenth comparators 11.
The resistor 109 connected to the comparison inputs 111'' and 112'' of No. 1,112 and the capacitor 110 and the electromagnetic valve circuit 113 are connected respectively, and when a flame is detected due to the FET 117 being turned off, the electromagnetic coil 105 is , 106 are energized.

The output of the seventh comparator 90 is connected between the resistor 99 and the diode 102, and the output of the seventh comparator 90 is connected between the resistor 99 and the diode 102.
20 between the diode 48 and the capacitor 47 constituting the hot water supply side holding timer 40, and further connected between the diode 102 and the capacitor 101 to the output of the first comparator 36 via the diode 121 in the charging direction of this capacitor. are doing. Therefore, the bath side flame detection circuit 61 or the hot water supply side flame detection circuit 11
When FETs 62, 63, 117, and 118 of transistor 6 are turned on and a so-called misfire signal is output, transistor 6
8,119 are turned off, and the first and second comparators 36,9
0 output goes high, capacitors 47 and 101
is charged, inverts the outputs of the second and eighth comparators 37 and 91 to low, turns on the transistors 50 and 104, turns off the first and third switching elements 49 and 103, and turns the outputs of the second and eighth comparators 37 and 91 low. 3. Fourth solenoid valve 11,1
2, 13, and 14 to stop all combustion.

Further, 122 is an inverter circuit for obtaining alternating current signals for flame detection and discharge ignition, which is supplied with power from the second switching element 54 and the fourth switching element 108 via backflow prevention diodes 123 and 124, respectively, and is connected to an inverter transformer. One of the secondary windings 126 of 125 includes a diode 127, a capacitor 128, a trigger element 129, and a step-up transformer 13.
0 and the fourth comparator 60 and the ninth comparator 11
Ignition switching element 1 which receives the output of 1 as input
A DC blocking capacitor 14 is connected to the other secondary winding 141.
2,143 respectively to the aforementioned rods 19 and 20.
are connected. The rods 19, 20 and the capacitors 142, 143 are connected to the respective flame detection circuits 116, from which signals are obtained by rectifying the flame. Further, the step-up transformer 13
The aforementioned ignition plugs 17 and 18 are connected to the double-wound secondary windings 144 and 144', respectively.

To briefly explain the operation on the bath side, the safety timer 3 is activated by closing the push button switch 34.
9 and hold timer 40 are activated, and the second comparator 3
At the high output of 7, the first and second switching elements 4
9 and 50 are turned on and the first and second solenoid valves 11 and 12 are turned on.
At the same time, the transistor 131 is turned off by the low output of the fourth comparator 60, and the igniter 140 is activated to ignite the burner set 5. When the burner set 5 is ignited, the FET 62 of the flame detection circuit 61,
This is detected by turning off transistor 63, and transistor 6
8 is turned on to maintain the second comparator 37 at a high output, and the transistors 58 and 59 are biased on through the diode 73 to keep the first and second solenoid valves 11 and 12 open, and the transistor 70 is turned on. Turns on and energizes the self-holding relay 69 and its contact 6
Close 9'. Therefore, this light emitting diode 66
After confirmation by the light emission, the push button switch 34 is released. When the water temperature in the bathtub 22 reaches the set temperature, the outputs of the fifth and sixth comparators 77 and 80 are reversed to high, turning on the SCR 81 and turning off the first switching element 49, thereby self-maintaining. Contact 69' of relay 69 opens to stop combustion in burner set 5.

Next, to briefly explain the operation on the hot water supply side, when the water flow switch 35 is closed due to opening of the hot water faucet, etc., the third and fourth switching elements 103 and 108 are turned on by the high output of the eighth comparator 91. ,
At the high output of the 10th comparator 112, the solenoid valve circuit 11
3 is activated to open the third and fourth solenoid valves 13 and 14 to supply gas to the burner set 6. At the same time, the low output of the ninth comparator 111 turns off the transistor 131 and activates the igniter 140. performs a series of ignition operations. When ignited by this, the FETs 117 and 118 of the flame detection circuit 116 turn off to detect this, rapidly charge the capacitor 110 of the forced ignition timer, and invert the output of the ninth comparator 111 to high. The transistor 131 is turned on to stop the igniter 140, and the transistor 119 is turned on to lower the output of the seventh comparator 90 to a low level to prevent the capacitor 101 from being charged below the inversion level of the eighth comparator 91. is held at high output.

Also, if one of the burner sets 5, 6 misfires, the flame detection circuit 116's FETs 62, 63,
When transistors 117 and 118 are turned on and a misfire signal is output, transistors 68 and 119 are turned off and the outputs of the first and seventh comparators 36 and 90 become high, charging the capacitors 47 and 101 and 2. Invert the output of the eighth comparator 37, 91 to low and turn off the first and third switching elements 49, 103;
Then, by charging the other capacitor 101 or 47 through the diode 121 or 120, the other switching element 103, 49 is turned off, thereby stopping each combustion operation of each burner 5, 6.

In the above embodiment, the hold timers 40 and 94 are each provided, but one may be configured to serve as both. Also, the contact 69' of the self-holding relay 69,
Capacitor 4 after opening water switch 35
At a predetermined discharge time of 7,101, the contact 6
9', even if the water flow switch 35 is closed, the second and eighth
A series of ignition operations cannot be performed until the comparators 37 and 91 are inverted to high, and safety operations such as providing a time for discharge of raw gas are performed.

As mentioned above, the combustion control device according to the present invention has a solenoid valve that independently controls opening and closing installed in each fuel flow path, and is capable of controlling blinking independently, and also controls a plurality of combustors housed in the same case. ,CR
The system is equipped with a hold timer consisting of a comparator that compares the output of the integrating circuit with a predetermined reference level, and the output of the comparator is inverted by charging or discharging the capacitor in response to the misfire signal of each flame detection circuit. The inverted output turns off the switching elements that control the energization of the control circuit that opens and closes the solenoid valves of each combustor, and in the event of a misfire in any combustor, combustion in all combustors is stopped. Safety can be achieved by stopping combustion in all combustors even if any combustor misfires.

In addition, when the burner is not ignited within a predetermined set time during ignition operation, so-called mis-ignition, a hold timer is installed to stop the igniter operation and close the solenoid valve for fuel supply. It can be used to perform the above-mentioned safe operation, and can be easily combined with conventional circuits.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a bathtub with a gas water heater equipped with a combustion control device according to the present invention, and FIG. 2 is an electric circuit diagram thereof. 2...Exterior case, 11, 12, 13, 14...
...Solenoid valve, 36, 37, 55, 60, 77, 8
0, 90, 91, 111, 112... Comparator, 4
9, 54, 103, 108... switching element, 61, 116... flame detection circuit.

Claims (1)

[Scope of utility model registration request] In a system in which a solenoid valve that independently controls opening and closing is installed in each fuel flow path and can independently control blinking and control multiple combustors housed in the same case, the output of the integral circuit by CR is set to a predetermined value. and a safety timer that charges or discharges the capacitor of the integrating circuit based on a misfire signal of the flame detection circuit that detects the flame of the combustor, The misfire signal from the flame detection circuit inverts the output of the comparator of the hold timer via the safety timer, and this inverted output controls the energization of the control circuit section that opens and closes the solenoid valve of each combustor. A combustion control device that turns off each switching element and stops combustion in all combustors even if any combustor misfires.