JPS6320926Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a range hood exhaust system suitable for kitchens equipped with two or more gas ranges, such as in restaurants and hotels.

In kitchens equipped with two or more gas ranges, such as in restaurants and hotels, the air flow rate of exhaust fans is set according to the total amount of gas such as smoke and hot air generated from multiple burners. As a range hood exhaust system that saves electricity, the intake side end of the exhaust duct is connected to the range hood installed above the gas range, and the opening degree of the exhaust duct is controlled by a torque motor. An air volume damper to be adjusted is installed, and the control voltage of the torque motor is controlled by a variable resistor linked to the rotation of the ignition knob of the gas range to adjust the opening degree of the air volume damper, and the exhaust duct is An exhaust fan with variable air volume is attached to the exhaust side end of the exhaust duct, and a pressure sensor installed on the intake side of the exhaust fan detects the pressure inside the exhaust duct, and the exhaust fan is adjusted according to the magnitude of the pressure. It is known that the number of rotations or the angle of the blades can be adjusted (see Japanese Utility Model Application No. 57-139133).

However, in the above-mentioned known exhaust system, the variable resistor that is linked to the ignition knob of the gas range wears out with use, becomes dirty with oil used for cooking, and its resistance changes, and the resistance value changes as well. The installed pressure sensor may malfunction due to temperature changes in the exhaust gas passing through the exhaust duct or the adhesion of oil smoke, so tedious work such as cleaning or replacing the variable resistor and pressure sensor described above is required. In addition, there were other inconveniences such as the exhaust becoming unsmooth.

This idea detects the flow rate of fuel gas and adjusts the opening of the range hood's air volume damper and the exhaust volume of the exhaust fan accordingly.
This eliminates the need for the installation of conventional variable resistors and pressure sensors and the maintenance work associated with this installation, and allows for smooth evacuation.

In other words, this idea connects the intake side branch ends of the exhaust ducts to the range hoods installed above each of the gas ranges, and connects an air volume damper whose opening degree can be adjusted to the branch ends. An exhaust fan with a variable air volume is attached to the exhaust side end of the exhaust duct, and a flow rate detector is attached to each of the main gas supply pipe and branch pipe for supplying fuel to the gas range. The range hood exhaust device is characterized in that the opening degree of the air volume damper and the exhaust air volume of the exhaust fan are adjusted based on the gas flow rate of the main pipe.

Examples of this invention will be described below with reference to the drawings.

1 is a gas range equipped with two gas burners (not shown), 1a is an ignition knob,
This gas range 1 is connected to a main gas supply pipe 2 via a branch pipe 3, and these main gas supply pipe 2 and branch pipe 3 are provided with bypass pipes 2a and 3a, respectively.
Slight differential pressure transmitters 4 and 5 are installed via the
The flow rate of the fuel gas flowing through the main gas supply pipe 2 and the branch pipe 3 is detected, and a current corresponding to the flow rate is taken out as an output signal. A plurality of the above-mentioned gas ranges 1 are arranged in parallel, and a range hood 6 is provided above each of the plurality of gas ranges 1, and an exhaust duct 7 is connected to the upper end of each range hood 6 via a branch end 7a. An air volume damper 8 whose opening degree can be adjusted by a torque motor 8a is attached to this branch end 7a, and the exhaust duct 7
A variable air volume exhaust fan 9 is attached to the exhaust side end of the fan 9, which can adjust the air volume by changing the rotation speed. The slight differential pressure transmitter 5 of the branch pipe 3 is connected to the torque motor 8a of the air volume damper 8, and the slight differential pressure transmitter 4 of the gas supply main pipe 2 is connected to the exhaust fan 9.
connected via.

In the above structure, when the ignition knobs 1a, 1a provided on the gas range 1 are rotated to ignite the burner, the fuel gas branch pipe 3 is turned in accordance with the total rotation amount of the two ignition knobs 1a, 1a. According to the flow rate of this fuel gas, carbon dioxide gas, smoke, etc. are generated, and the above flow rate is detected by the slight differential pressure transmitter 5, and the air volume damper 8 is opened according to the above flow rate.
For example, if one of the two knobs 1a, 1a is fully open and the other is fully closed, and if knob 1
When both a and 1a have an opening degree of 1/2, the opening degree of the air volume damper 8 is set to 1/2. Furthermore, when the two knobs 1a, 1a are both fully open, the air volume damper 8 is fully opened. Then, the total amount of fuel gas flowing through the plurality of branch pipes 3 is detected by the slight differential pressure transmitter 4 of the gas supply main pipe 2, and a current corresponding to the total amount flows to the inverter 10, and the exhaust fan 9 is activated. The gear will be changed. Therefore, the rotation speed of the exhaust fan 9 is set according to the total amount of gas such as smoke flowing through the exhaust duct 7.

In the above embodiment, by attaching a blade angle conversion regulator to the exhaust fan 9 instead of the inverter 10, it is possible to increase or decrease the amount of exhaust air by changing the blade angle. Further, instead of the slight differential pressure transmitters 4 and 5, other combinations of flow rate detectors and transmitters can be used. It goes without saying that the number of gas ranges 1 may be three or more.

As explained above, this idea detects the gas flow rate for each gas range and adjusts the range hood's air volume damper, and also detects the total gas flow rate for two or more gas ranges to control the exhaust air volume of the exhaust fan. Since the exhaust fan is driven according to the total amount of gas generated from multiple gas ranges, power consumption is greatly reduced, and detection due to the influence of temperature and oil smoke is reduced. There are no errors, and the effort required to maintain the detection unit is reduced.

[Brief explanation of the drawing]

The drawing is an explanatory diagram of an embodiment of this invention. 1...Gas range, 2...Gas supply main, 3...
...Branch pipe, 4,5...Small differential pressure transmitter (flow rate detector),
6...Range hood, 7...Exhaust duct, 7a...
... Branch end, 8 ... Air volume damper, 8a ... Torque motor, 9 ... Exhaust fan, 10 ... Inverter.

Claims (1)

[Scope of Claim for Utility Model Registration] [1] The intake side branch ends of the exhaust duct are connected to the range hoods provided above each of the gas ranges, and the opening degree of the exhaust duct is adjustable. Attach an air volume damper and an exhaust fan with variable air volume to the exhaust side end of the exhaust duct, install flow rate detectors to the main gas supply pipe and branch pipes for supplying fuel to the gas range, and An exhaust system for a range hood, characterized in that the opening degree of the air volume damper is adjusted based on the gas flow rate of the pipe, and the exhaust air volume of the exhaust fan is adjusted based on the gas flow rate of the main pipe. [2] The air volume damper is equipped with a torque motor for adjusting the opening degree, and the flow rate detector of the gas supply branch pipe is equipped with a transmitter that can increase or decrease the current according to the increase or decrease in the gas flow rate, The range hood exhaust system according to claim 1, wherein the output signal of the transmitter is input to the torque motor. [3] The flow rate detector of the gas supply main is equipped with an oscillator that can increase or decrease the current according to the increase or decrease in the gas flow rate, and the power frequency of the exhaust fan is converted by the output signal of this oscillator. An exhaust system for a range hood according to claim 1 or 2 of the utility model registration claim.