JPH04260736A - Automatic ventilation device - Google Patents

Abstract

PURPOSE:To enable an operation time of a ventilation fan to be set by a user to a time in correspondence with a condition in a kitchen where the ventilation fan is used and further to enable ventilation to be carried out in correspondence with a structure and an area of the kitchen and a fixing position of a smoke sensing element. CONSTITUTION:An automatic ventilation device is comprised of an operating means 4 for operating a ventilation fan when a smoke sensing element 1 detects gas more than a specified value and a delay operation time determining means 8 for varying a delay operation time after a difference between a concentration of smoke at the starting of operation time and a concentration of smoke during operation returns back to a value lower than its predetermined value through a switch 7.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to an automatic ventilation system that detects changes in reducing gas in the kitchen and controls the operation of a ventilation fan according to the detected output, in order to automatically ventilate the kitchen. be.

0002

2. Description of the Related Art In recent years, automatic ventilation systems that automatically operate ventilation fans by detecting smoke or gas have become mainstream.

A conventional automatic ventilation system of this kind is configured as shown in FIG. 5, for example, and when gas or smoke reaches a smoke detection element of the automatic ventilation system and the gas concentration reaches a predetermined value of 31 or higher, the ventilation system starts operating. . While the ventilation system is in operation, if the gas stops coming into contact with it or the gas concentration decreases and the smoke detection element no longer responds, the capacitor and discharge resistor connected to the relay circuit stop the ventilation action for a certain period of time (Δt =
t2-t1) was to be continued.

0004

[Problems to be Solved by the Invention] In this conventional configuration, the reducing gas from cooking is detected by a smoke detection element and the ventilation fan is started and stopped. The state of smoke detection differs depending on the installation position of the smoke detection element, and the ventilation fan may not operate even when cooking, or may not stop even after exhausting reducing gas, and the purpose of ventilation may not be fully achieved. It was impossible.

[0005] The present invention solves the above problems, and aims to provide an automatic ventilation system that allows a user to arbitrarily set the operation time of a ventilation fan to a time that suits the conditions of the kitchen in which the kitchen is used. It is something.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the automatic ventilation system of the present invention includes a smoke detection circuit that detects reducing gas and detects the input of a smoke detection element whose resistance value changes; an operating means for operating the ventilation fan when the smoke detection element detects a reducing gas of a predetermined value or more; and a switch for controlling the difference between the smoke concentration at the start of the operating time and the detected smoke concentration during operation to return to less than the predetermined value. and a remaining delay operation time determining means for changing the remaining delay operation time from .

[0007]

[Function] With this configuration, when the smoke detection element detects a predetermined amount or more of reducing gas, the ventilation fan is immediately operated by the operating means, and the smoke concentration at the start of operation and the detected smoke concentration during operation are determined by the setting state of the switch. The remaining delay operation time after the difference returns to less than the predetermined value will be changed.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

As shown in the figure, a microcomputer 3 is provided to receive a signal from a smoke detection circuit 2 that detects the input of a smoke detection element 1 whose resistance value changes when a reducing gas is detected. 3, when the smoke detection element 1 detects reducing gas of a predetermined value or higher (approximately 2 ppm per 10 seconds), the operating means 4 starts operating the motor 6 through the drive circuit 5. When the difference between the smoke concentration at the start of operation and the detected smoke concentration during operation returns to less than a predetermined value (approximately 2 ppm or less), switch 7
The motor 6 is operated via the drive circuit 5 by the remaining operating time determining means 8 for the remaining operating time set by the signal input to the computer 3.

Next, the operation of the automatic ventilation system having the above structure will be explained based on FIGS. 2 to 4. First, in step 11, smoke data is input from the smoke detection circuit 2 to the microcomputer 3. If the motor 6 is stopped in step 12, in step 15, smoke data is inputted to the microcomputer 3 from the smoke detection circuit 2. When a toxic gas is detected, the motor 6 is operated through the drive circuit 5 in step 16, and the smoke data at the start of operation is stored in step 17. If the motor 6 is operating in step 12, the difference between the smoke data at the start of operation and the current detection data is calculated, and if it is above a predetermined value (2 ppm or less), the motor 6 continues to operate and the smoke data is below the predetermined value. If so, in step 14, the remaining delay operation is determined by setting the switch 7. For example, if the R0 and R1 ports of the microcomputer 3 are connected as shown in Figure 3, when the microcomputer 3 determines that both the R0 and R1 ports are Lo, the motor 6 will run for 5 minutes and then stop. become.

As described above, according to the embodiment, the user can set the remaining operating time after the reducing gas approaches the initial state while the ventilation fan is in operation by switching the switch 7. This will allow for proper ventilation.

[0012] In the embodiment, the predetermined value and remaining delay operation time, which serve as criteria for determining whether to start or stop the motor 6, are not limited to those in the embodiment, and can be set to other values according to the user's sense. Nor.

[0013]

[Effects of the Invention] As is clear from the above description of the embodiments, according to the present invention, the ventilation fan may stop or may not stop even though gas remains in the kitchen after cooking. In this case, it is possible to provide an automatic ventilation system that can change the remaining delay operation time using the switch 4 and perform ventilation that suits the structure and size of the kitchen and the mounting position of the smoke detection element.

[Brief explanation of the drawing]

FIG. 1: Block diagram of an automatic ventilation system according to an embodiment of the present invention.

[Figure 2] Electrical circuit diagram of the automatic ventilation system

[Figure 3] Explanatory diagram showing the connection status of the microcomputer and switch of the automatic ventilation system

[Figure 4] Flowchart of the operation program of the automatic ventilation system

[Figure 5] Characteristic diagram of gas concentration and ventilation fan operating time in a conventional automatic ventilation system

[Explanation of symbols]

1 Smoke detection element 2 Smoke detection circuit 4. Operating means 7 Switch 8. Remaining slow operation time determination means

Claims (1)

[Claims] 1. A smoke detection circuit that detects the input of a smoke detection element whose resistance value changes when detecting reducing gas, and which operates a ventilation fan when the smoke detection element detects reducing gas of a predetermined value or more. and a remaining delay operation time determining means for changing the remaining delay operation time after the difference between the smoke concentration at the start of operation and the detected smoke concentration during operation returns to less than a predetermined value using a switch. Ventilation equipment.