JPS6380141A - Automatic operating circuit for kitchen ventilation fan - Google Patents

Abstract

PURPOSE:To enable the automatic operation of a ventilation fan to be carried out and to make the convenient use of the same by a method wherein a first sensing part for sensing a high voltage discharge accompanying the igniting operation of a kitchen range and a second sensing part for sensing an increase in temperature near the ventilation fan are provided and if there is an output from either one of the sensing parts, the power supply circuit for the ventilation fan is closed. CONSTITUTION:An automatic operating circuit for a kitchen ventilation fan is provided with a first sensing part for sensing a high voltage discharge accompanying an igniting operation of a range L and a second sensing part 2 for sensing an increase in temperature near the ventilation fan, and a power supply circuit 3 which is open is closed if there is an output from either one of the sensing parts 1 and 2. The first sensing part 1 comprises a sensing coil 5, an amplifier 6, a comparator 7 for comparing a voltage with a reference voltage and outputting the voltage if the same exceeds the reference voltage and a timer 8. The second sensing part 2 comprises a high temperature thermistor 9, a room temperature thermistor 10 and a comparator 11. It is possible to close the power supply circuit for the ventilation fan with the first sensing part 1 and the second sensing part 2 and so there occurs no unfavorableness that the ventilation fan is not operated during use of the range L.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is for automatically operating a kitchen ventilation fan such as a range hood fan set aside for ventilation in the kitchen according to the situation where ventilation is required. This relates to automatic driving circuits.

[Prior Art] The above-mentioned conventional automatic operation circuit for a kitchen ventilation fan has a configuration as disclosed in Japanese Utility Model Publication No. 53-28277. That is, as shown in Fig. 4, it consists of a high-temperature thermistor 21 installed in the hood of the range-to-door oven installed above the range, a room temperature thermistor 22 installed at a distance from this, and several resistors. Switching that detects whether or not a temperature condition requiring ventilation is present in a bridge circuit 23 for temperature detection, and opens and closes a power supply circuit related to a motor 24 of a range-to-door oven with an output from the bridge circuit 23 indicating that a condition requiring ventilation exists. It is configured to move the elements and operate the range-to-door amplifier.

When the microwave is ignited and cooking begins, heated air rises, warming the high temperature thermistor 21 and creating a difference in resistance between it and the room temperature thermistor 22. This causes the bridge circuit 23 to become unbalanced, and its output is configured as a control signal for operating a switching element that opens and closes the power supply circuit for the motor 24, causing the motor 24 to rotate and ventilation to be performed.

[Problems to be Solved by the Invention] In the conventional automatic operation circuit of the kitchen ventilation fan described above, it takes time for the balance of the bridge circuit 23 to collapse, and during this time even if there is a situation that requires ventilation. There is a problem that ventilation operation is not performed. That is, even if the microwave is lit and cooking has started, the ventilation operation will not start unless the high temperature thermistor 21 comes into contact with the high temperature air accompanying cooking and is heated to a predetermined temperature, and the mounting hole for the high temperature thermistor 21 will not start. This has the disadvantage that the dynamic characteristics of the circuit also fluctuate.

This invention was made in order to solve such conventional problems, and it is possible to start the ventilation fan when the range starts to be used, and after the start of operation, it is determined whether or not ventilation is required depending on the temperature condition. The purpose of the present invention is to obtain an automatic operation circuit for a kitchen ventilation fan that is easy to use and can automatically operate the ventilation fan.

[Means for Solving the Problems] The automatic operation circuit for a kitchen ventilation fan according to the present invention is a circuit that automatically operates a ventilation fan that exhausts the air in the kitchen that becomes polluted due to boiling, and is adapted to the ignition operation of the kitchen range. The ventilation fan is equipped with a first detection section that detects a high-pressure discharge associated with the ventilation fan, and a second detection section that detects a temperature rise in the vicinity of the ventilation fan. It is configured to close the ventilation fan power supply circuit.

[Effect].

In this invention, when the range is ignited, the first detection section detects the high voltage discharge accompanying the ignition operation of the range, and the ventilation fan power supply circuit is closed. Even if the second detection section detects a temperature rise in the vicinity of the ventilation fan as cooking progresses, the ventilation fan power supply circuit is closed.

[Example] Figures 1, 2, and 3 all show an automatic operation circuit for a kitchen ventilation fan as an example of the present invention.
The automatic operation circuit for the kitchen ventilation fan in this example is for the kitchen range L.
The first detection section 1 detects high-pressure discharge accompanying the ignition operation of the ventilation fan, and the second detection section 2 detects a temperature rise in the vicinity of the ventilation fan. The feature is that the ventilation fan power supply circuit 3, which is normally open, is configured to be closed if there is one. As can be seen from the block diagram in FIG. 1, the circuit related to the first detection section 1 and the circuit related to the second detection section 2 are configured in parallel, and are connected to two input terminals of the OR gate 4, respectively. ing.

The first detection unit 1 includes a detection coil 5 that generates an induced pulse by the ignition spark caused by the ignition operation of the range L, an amplifier 6 that amplifies this output (see the opening in FIG. 3), and converts the output of the amplifier 6 to a reference voltage. It consists of a comparator 7 which outputs an output when the reference voltage is exceeded (see FIG. 3C), and a timer 8 which operates upon receiving the output of the comparator 7 (see FIG. 3B).

The second detection section 2 includes a high temperature thermistor 9, a room temperature thermistor 10, and a comparator 11. As shown in Fig. 2, this circuit uses a voltage divided by one high-temperature thermistor and a resistor 12 connected in series, and a room-temperature thermistor 1.
The comparator 11 compares the magnitude of the voltage divided by 0 and the resistor 13 connected in series with it, and when the difference between the two (see E in Figure 3) exceeds a certain amount, it is output to the comparator 11 (see Figure 3). This configuration is basically the same as the detection system of the conventional example described above.

The comparator 7 in the first detection section 1 also has the same basic movement 1 as the comparator 11 described above. However, the comparator 7 has a resistor 1 in series.
The voltage divided by voltages 4" and 15 is applied as a reference voltage to the non-inverting input terminal, and the output of the amplifier 6 is input to the inverting input terminal. A timer 8 operated by the output of the comparator 7 is
The output is at H level for a time determined by the resistor 16 and capacitor 17, and after that time, the output is at L level.

The outputs of the first detection section 1 and the second detection section 2 are input to the OR gate 4, and if there is an output from either one, it will be output to the base of the transistor 18 via a resistor. The output of the transistor 18 is applied to the gate of a 1-RIAC 20 as a switching element inserted in the ventilation fan power supply circuit 3 for the ventilation fan motor 19, making the TRIAC 20 conductive. When the triac 20 becomes conductive, the ventilation fan power supply circuit 3 is closed, power is supplied to the motor 19, and the ventilation fan is put into operation.

Therefore, in the automatic operation circuit of the kitchen ventilation fan of this example, when the range L is ignited (see Figure 3 A and G), the first detection unit
detects the high-pressure discharge accompanying the ignition operation of the range L, and closes the ventilation fan power supply circuit 3 for a limited time. Then, within this time period, the second detection unit 2 detects a temperature rise in the vicinity of the ventilation fan as the cooking progresses, keeps the ventilation fan power supply circuit 3 closed, and continues the ventilation operation. From the circuit perspective, ventilation operation stops when there is no output from either the first detection section 1 or the second detection section 2, but in reality this means that the second detection section 2 outputs no output.
This is when there is no output. In other words, the ventilation fan will be stopped when the temperature condition reaches such a level that ventilation is no longer required (see Figure 3). There are no inconveniences and it is easy to use.

[Effects of the Invention] As is clear from the above description of the embodiments, the automatic operation circuit for a kitchen ventilation fan of the present invention includes a first detection unit that detects high-pressure discharge accompanying the ignition operation of a kitchen range; and a second detection section that detects a temperature rise in the vicinity, and is configured so that if there is an output from either of the above detection sections, the ventilation fan power supply circuit, which is normally open, is closed. Therefore, when the range is ignited, the first detection unit detects the high voltage discharge accompanying the ignition operation of the range, and closes the ventilation fan power supply circuit.

Moreover, as the cooking progresses, the temperature rise in the vicinity of the ventilation fan is detected by the second detection section, and this also allows the ventilation fan power supply circuit to be closed. Therefore, there will be no inconvenience such as the ventilation fan not being operated even though range L is being used, which is very convenient.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an automatic driving circuit as an embodiment of the present invention, FIG. 2 is an electric circuit diagram thereof, and FIG. 3 is a timing chart showing operational timing.
FIG. 4 is an electrical circuit diagram showing a conventional example. In the figure,
1 is a first detection section, 2 is a second detection section, 3 is a ventilation fan power supply circuit, 4 is an OR gate, 5 is a detection coil, 9 is a high temperature thermistor, 10 is a room temperature thermistor, and 20 is a triac. Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent: Masuo Oiwa (2 people) Figure 1 Figure 2 Figure 8 Figure 4 Procedural amendment (voluntary)

Claims (2)

[Claims] (1) This is a circuit that automatically operates a ventilation fan that exhausts kitchen air that becomes polluted as a result of boiling, and includes a first detection part that detects high-pressure discharge associated with the ignition operation of the kitchen range, and a circuit that detects temperature rises near the ventilation fan. and a second detection section for detecting, and is configured to close a normally open ventilation fan power supply circuit if there is an output from either one of the detection sections. Automatic operation circuit for ventilation fans. (2), the first detection unit includes a coil that generates an induction pulse by high-pressure discharge accompanying the ignition operation of the range;
2. The automatic operation circuit for a kitchen ventilation fan according to claim 1, wherein the detection section includes an element whose electrical characteristics change depending on temperature changes.