JPH0875202A - Ventilation control device - Google Patents

Abstract

(57) [Summary] [Purpose] To enable automatic switching to commercial operation when operating the fan at the rated value or when the inverter is abnormal. [Configuration] Normally, the contact 41a of the electromagnetic contactor MC1 and the contact 43a of the electromagnetic contactor MC3 are short-circuited, and the electromagnetic contactor MC2
42a of the inverter is opened, and the commercial power source 32 is connected to the inverter 3
0 to the fan motor 36. When the controller maximizes the output frequency of the inverter 30 to operate the fan at the rated value, the frequency detection terminal FU becomes low level, the contact 43a of the electromagnetic contactor MC3 is opened, and the contact 42a of the electromagnetic contactor MC2 is short-circuited. , Commercial operation is performed. When the stall prevention operates, the overload alarm terminal OL of the inverter 30 becomes low level,
The contact 42a is short-circuited, the contact 43a is opened, and commercial operation is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ventilation volume control device for controlling a fan rotation speed by using an inverter to control a ventilation volume.

[0002]

2. Description of the Related Art In a kitchen room for business use, etc., in addition to ventilation equipment such as an exhaust fan and an air supply fan, a ventilation amount control device for controlling a ventilation amount according to a combustion gas amount of cooking equipment is provided.
It constitutes a ventilation system.

FIG. 5 is an explanatory diagram showing an example of the configuration of a ventilation system. As shown in this figure, a cooking appliance 11 is provided in the kitchen 10, and a hood 12 is provided above the cooking appliance 11. An exhaust fan 14A is connected to the hood 12 via an exhaust duct 13. An outside air outlet 15 and an conditioned air outlet 16 are provided on the ceiling in the kitchen room 10. An air supply fan 14B is connected to the outside air outlet 15 via an air supply duct 17. An air conditioner 20 is connected to the conditioned air outlet 16 via an air conditioning duct 19. Also,
A gas pipe 21 is connected to the cooking appliance 11, and a gas meter 22 is provided in the middle of the gas pipe 21.

Further, in the ventilation system shown in FIG. 5, as the ventilation amount control device, an inverter 30A for controlling the rotation speed of the exhaust fan 14A, an inverter 30B for controlling the rotation speed of the air supply fan 14B, the gas meter 12, The controller 31 is connected to the inverter 30A and the inverter 30B. With this ventilation control device,
The controller 31 obtains the combustion gas amount of the cooking appliance 11 from the output of the gas meter 22, controls the inverters 30A and 30B according to the combustion gas amount, and the exhaust fan 14A.
And the rotation speed of the air supply fan 14B are changed to prepare the cooking appliance 1
Ventilation according to the amount of combustion gas of 1 is performed.

FIG. 6 is an explanatory diagram showing wiring of an inverter, a power supply and a fan in a conventional ventilation system.
As shown in this figure, the three-phase commercial power source 32 is connected to the inverter 30 (3 by way of the breaker 33 and the electromagnetic contactor 34).
Represents 0A and 30B. ) Power input terminal is connected. The output terminal of the inverter 30 has an electromagnetic contactor 3
Fan 14 (representing 14A and 14B) through 5.
Motor 36 is connected. In addition, the electromagnetic contactor 34
One end of an electromagnetic contactor 37 is connected between the inverter 30 and the inverter 30, and the other end of the electromagnetic contactor 37 is connected between the electromagnetic contactor 35 and the motor 36. The electromagnetic contactor 35 and the electromagnetic contactor 37 operate in conjunction with the manual changeover switch 38, and when one is short-circuited, the other is opened. With such a configuration, it is possible to switch between the inverter operation and the commercial operation by operating the manual changeover switch 38.

[0006]

In the ventilation system shown in FIG. 5, when the combustion gas amount of the cooking appliance 11 is maximum, the frequency of the inverter 30 is set to 50 Hz, which is the maximum frequency, and the fan 14 is operated at the rated value. , In this case the same 50
There is a problem that the power consumption increases due to the loss in the inverter 30 as compared with the case of performing the commercial operation by the commercial power source 32 of Hz.

Further, when the inverter 30 is in an abnormal state, it is necessary to manually restore the operation or manually switch to the commercial operation, which complicates the processing and may delay the processing and adversely affect the inverter 30 and other devices. There is a problem.

The present invention has been made in view of the above problems, and an object thereof is to control the ventilation amount so that the fan can be automatically switched to the commercial operation when the fan is operated at the rated value or when the inverter is abnormal. To provide a device.

[0009]

A ventilation amount control apparatus according to claim 1, wherein an inverter for converting a frequency of a commercial power source and outputting it to a fan for ventilating a kitchen room, and a cooking appliance in the kitchen room are provided. Detecting means for detecting the amount of combustion gas, control means for controlling the output frequency of the inverter according to the amount of combustion gas detected by this detecting means, and commercial power to the fan via the inverter depending on the state of the inverter. It is provided with a switching means for automatically switching between a connected state and a state in which the commercial power source is connected to the fan without passing through the inverter.

In this ventilation volume control device, the output frequency of the inverter is controlled by the control means in accordance with the combustion gas volume detected by the detection means to control the ventilation volume. Further, the switching means automatically switches between a state in which the commercial power source is connected to the fan via the inverter and a state in which the commercial power source is connected to the fan without the inverter according to the state of the inverter.

According to a second aspect of the present invention, there is provided the ventilation amount control apparatus according to the first aspect, wherein the switching means uses a commercial power source via the inverter when the output frequency of the inverter reaches a predetermined frequency. It automatically switches from the state of connecting to the fan to the state of connecting the commercial power source to the fan without going through the inverter.

A ventilation amount control device according to a third aspect is the ventilation amount control device according to the first aspect, wherein the switching means switches the commercial power source from the state in which the commercial power source is connected to the fan via the inverter when the inverter is abnormal. It automatically switches to the state of connecting to a fan without going through an inverter.

A ventilation amount control device according to a fourth aspect is the ventilation amount control device according to any one of the first to third aspects, wherein the switching means is provided between the inverter and the fan, and the control circuit in the inverter is provided. Of the first electromagnetic contactor that operates according to the output signal of the power supply, a bypass that connects the commercial power supply and the fan without the intermediary of the inverter, and a bypass provided in the bypass and that responds to the output signal of the control circuit in the inverter. And a second electromagnetic contactor that operates in accordance with the above.

In this ventilation volume control device, the first electromagnetic contactor and the second electromagnetic contactor are connected in accordance with the output signal of the control circuit in the inverter.
The electromagnetic contactor is operated, which automatically switches between the state in which commercial power is connected to the fan via the inverter and the state in which commercial power is connected to the fan without the inverter, depending on the state of the inverter. To be

According to a fifth aspect of the present invention, there is provided a ventilation amount control device according to any one of the first to third aspects, wherein the switching means has a first electromagnetic contact provided between the inverter and the fan. Device, a bypass for connecting a commercial power source and a fan without going through the inverter, a second electromagnetic contactor provided in the bypass, and a first electromagnetic contactor according to an output signal of a control circuit in the inverter. An electromagnetic contactor control means for operating the contactor and the second electromagnetic contactor.

In this ventilation amount control device, the electromagnetic contactor control means operates the first electromagnetic contactor and the second electromagnetic contactor according to the output signal of the control circuit in the inverter, whereby the inverter is operated. Depending on the state, the state in which the commercial power source is connected to the fan via the inverter and the state in which the commercial power source is connected to the fan without the inverter are automatically switched.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 and 2 relate to the first embodiment of the present invention.

The configuration of the ventilation system in which the ventilation control device of this embodiment is used is the same as that shown in FIG. Further, the ventilation amount control device of the present embodiment, as shown in FIG. 5, an inverter 30A for controlling the rotation speed of the exhaust fan 14A, an inverter 30B for controlling the rotation speed of the air supply fan 14B, the gas meter 12, Inverter 30
Controller 3 connected to A and inverter 30B
1 and.

FIG. 1 is an explanatory diagram showing the connection of the inverter, the power supply, and the fan in the ventilation control device of this embodiment. As shown in this figure, the inverter 30 includes power source input terminals R, S, T and control circuit power source terminals R1, S1.
And an output terminal U, V, W, and as output terminals of the control circuit in the inverter 30, an instantaneous power failure terminal IPF, an overload alarm terminal OL, a frequency detection terminal FU and an open collector output common terminal SE. I have it.
An example of such an inverter 30 is “FREQR
There is an OL-A100 (trade name: manufactured by Mitsubishi Electric). When the instantaneous power failure or undervoltage protection operates, the instantaneous power failure terminal IPF turns on the internal transistor provided between it and the open collector output common terminal SE, and becomes a low level. The overload alarm terminal OL is provided between the open collector output common terminal SE and the open collector output common terminal SE when the current limit is applied when the overcurrent flows and the stall prevention that lowers the output frequency and prevents the overcurrent flows. Also, the internal transistor turns on and becomes low level, and when the stall prevention is released, the transistor turns off and becomes high level. In the frequency detection terminal FU, when the output frequency becomes equal to or higher than the arbitrarily set detection frequency, the internal transistor provided between the frequency detection terminal FU and the open collector output common terminal SE turns on,
It becomes low level. In this embodiment, the detection frequency is set to 50 Hz or a frequency slightly lower than 50 Hz.

The three-phase commercial power source 32 has a breaker 3
3 and the power input terminals R, S, T of the inverter 30 are connected via the contact 41a of the electromagnetic contactor MC1.
The motor 36 of the fan 14 is connected to the output terminals U, V, W of the inverter 30 via the contact 43a of the electromagnetic contactor MC3. Also, the breaker 33 and the electromagnetic contactor MC
The contact 43 of the electromagnetic contactor MC3 from between the contact 41a of 1
A detour 44 is provided between a and the motor 36, and a contact 42a of the electromagnetic contactor MC2 is interposed in the detour 44. The contact 42a of the electromagnetic contactor MC2 and the contact 43a of the electromagnetic contactor MC3 are mechanically interlocked, and when one is short-circuited, the other is opened. The control circuit power supply terminals R1 and S1 of the inverter 30 are connected to the R-phase and S-phase lines between the breaker 33 and the contact 41a of the electromagnetic contactor MC1.

In addition, the instantaneous power failure terminal IP of the inverter 30
The coil 41b of the electromagnetic contactor MC1, the coil 42b of the electromagnetic contactor MC2, and the coil 43 of the electromagnetic contactor MC3 are respectively connected to F, the overload alarm terminal OL, and the frequency detection terminal FU.
Each end of b is connected. These coils 41b,
The positive electrode of the DC power supply 45 is connected to the other ends of 42b and 43b, and the negative electrode of the DC power supply 45 is connected to the open collector output common terminal SE. In addition, each coil 41
A diode 46 as a surge killer for preventing noise is connected between both ends of b, 42b, 43b.

Although not shown, the input terminal of the control circuit of the inverter 30 is connected to the controller 31 shown in FIG.

FIG. 2 is a block diagram showing a schematic structure of the inverter 30 in FIG. As shown in this figure,
The inverter 30 is connected to the power supply input terminals R, S, and T, and a converter unit 51 that converts three-phase alternating current into direct current, and an inverter that converts the direct current output from the converter unit 51 into three-phase alternating current having an arbitrary frequency. And a section 52. A current limiting circuit 53 is provided on the positive power supply line between the converter unit 51 and the inverter unit 52, and an overvoltage protection circuit 54 and a smoothing capacitor 55 are provided between the positive power supply line and the negative power supply line. . Further, the inverter 30 includes a control circuit 56, and the control circuit 56 includes the control circuit power supply terminals R1 and S1, the instantaneous power failure terminal IPF, the overload alarm terminal OL, the frequency detection terminal FU, the open collector output common terminal SE, and the inverter. It is connected to the section 52, the current limiting circuit 53, and the overvoltage protection circuit 54. The control circuit 56 includes an inverter unit 52 and a current limiting circuit 5
3 and the overvoltage protection circuit 54, and controls the output terminals IP according to the state of the inverter 30 as described above.
F, OL and FU are set to high level or low level.

Next, the operation of the ventilation control system of this embodiment will be described.

The inverter 30 is normal and the cooking appliance 1
When the combustion gas amount of 1 is not the maximum, the contact 41a of the electromagnetic contactor MC1 and the contact 43a of the electromagnetic contactor MC3 in FIG. 1 are short-circuited, and the contact 42a of the electromagnetic contactor MC2 is open. In this state, the commercial power source 32 is connected to the motor 36 via the inverter 30. Then, the controller 31 in FIG. 5 obtains the combustion gas amount of the cooking appliance 11 from the output of the gas meter 22, controls the inverter 30 (30A, 30B) according to the combustion gas amount, and rotates as the combustion gas amount increases. The number of revolutions of the exhaust fan 14A and the air supply fan 14B is changed so as to increase the number, and ventilation is performed according to the combustion gas amount of the cooking appliance 11.

Next, when the combustion gas amount of the cooking appliance 11 becomes maximum, in order to operate the fan 14 at the rated value,
The controller 31 sets the output frequency of the inverter 30 to the maximum of 50 Hz. Then, the frequency detection terminal FU of the inverter 30 becomes low level, current flows through the coil 43b of the electromagnetic contactor MC3, and the contact 43 of the electromagnetic contactor MC3.
a is opened, and the contact 42a of the electromagnetic contactor MC2 is short-circuited. As a result, the commercial power supply 32 is connected to the motor 36 via the bypass 44 without passing through the inverter 30, and commercial operation is performed.

Next, when an instantaneous power failure or undervoltage protection is activated due to an abnormality in the inverter 30, the inverter 3
The instantaneous power failure terminal IPF of 0 becomes low level, current flows through the coil 41b of the electromagnetic contactor MC1, and the electromagnetic contactor MC1
The contact 41a of No. 1 is opened. As a result, the inverter 30 is disconnected from the commercial power supply 32.

Next, when the stall prevention is activated by the current limiting function due to the abnormality of the inverter 30 or the like, the overload alarm terminal OL of the inverter 30 becomes low level, and a current flows through the coil 42b of the electromagnetic contactor MC2 to cause electromagnetic contact. The contact 42a of the device MC2 is short-circuited, and the contact 43a of the electromagnetic contactor MC3 is opened. As a result, the commercial power source 32 does not go through the inverter 30 but goes through the bypass 44 and the motor 3
6 is connected and commercial operation is performed.

As described above, according to the ventilation amount control apparatus of this embodiment, when the fan 14 is operated at the rated value, it can be automatically switched to the commercial operation, and the inverter 3
It is possible to eliminate the loss due to 0 and reduce the power consumption.

The ventilation control system of this embodiment also has a fail-safe function of automatically switching to commercial operation when the inverter 30 is abnormal. Therefore, the inverter 3
It is not necessary to manually switch to commercial operation when 0 is abnormal, and it is possible to prevent adverse effects on the inverter 30 and other devices.

FIG. 3 is an explanatory view showing the connection of the inverter, the power supply and the fan in the ventilation amount control device of the second embodiment of the present invention, and FIG. 4 is the configuration of the ventilation amount control device of the second embodiment of the present invention. It is a block diagram showing.

As shown in FIG. 3, the inverter 30 in this embodiment has a frequency setting terminal 61 and an abnormal output terminal 6
2 and a frequency detection terminal 63. The abnormality output terminal 62 outputs an abnormality signal which becomes a high level when the inverter 30 has an abnormality. Further, the frequency detection terminal 63 has the inverter output frequency set to the set frequency (50
(Hz), it outputs a high-level detection signal. Further, the three-phase commercial power source 32 includes a breaker 33 and a contact 41a of the electromagnetic contactor MC1.
The power supply input terminals R, S, and T of the inverter 30 are connected via the. The output terminal U, V, W of the inverter 30 is connected to the fan 14 via the contact 43a of the electromagnetic contactor MC3.
Motor 36 is connected. Also, electromagnetic contactor MC
A detour circuit 44 is provided between the contact 41a of the first power input terminal R, S and T and between the contact 43a of the electromagnetic contactor MC3 and the motor 36. The detour circuit 44 includes a detour circuit 44 of the electromagnetic contactor MC2. The contact 42a is interposed. Electromagnetic contactor MC
The second contact 42a and the contact 43a of the electromagnetic contactor MC3 are mechanically or electrically linked so that when one is short-circuited, the other is opened.

As shown in FIG. 4, the frequency setting terminal 61 of the inverter 30 is connected to the controller 31, and the frequency setting signal from the controller 31 is input to the frequency setting terminal 61. Further, the abnormal output terminal 62 and the frequency detection terminal 63 of the inverter 30 are connected to the respective input terminals of the OR circuit 65, and the output terminal of the OR circuit 65 is connected to the controller 31 functioning as electromagnetic contactor control means. . When at least one of the abnormal signal from the abnormal output terminal 62 and the detection signal from the frequency detection terminal 63 becomes high level, the OR circuit 65.
A high-level signal is output from the controller and input to the controller 31. In addition, the controller 31
Normally, the contact 42a of the electromagnetic contactor MC2 is opened, the contact 43a of the electromagnetic contactor MC3 is short-circuited, and when a high level signal is input from the OR circuit 65, the electromagnetic contactor M
The contact 42a of C2 is short-circuited, the contact 43 of the electromagnetic contactor MC3
The coil 42b of the electromagnetic contactor MC2 is opened so as to open a.
And the coil 43b of the electromagnetic contactor MC3.

Further, in FIG. 4, a damper motor 66 is connected to the controller 31. The damper motor 66 is a motor that adjusts the opening degree of a damper provided in each branch duct when the exhaust duct 13 has a plurality of branch ducts corresponding to a plurality of cooking appliances, for example. And
The controller 31 outputs an opening degree setting signal to the damper motor 66 to control the damper motor 66 to arbitrarily set the damper opening degree.

In this embodiment, the inverter 30 is normal,
When the combustion gas amount of the cooking appliance 11 is not the maximum, the contact 43a of the electromagnetic contactor MC3 in FIG. 3 is short-circuited, and the contact 42a of the electromagnetic contactor MC2 is open.
In this state, the commercial power source 32 is connected to the motor 36 via the inverter 30.

On the other hand, when the inverter 30 is abnormal or when the output frequency of the inverter 30 reaches the set frequency (50 Hz), at least one of the abnormal signal from the abnormal output terminal 62 and the detection signal from the frequency detection terminal 63 of the inverter 30. Becomes a high level, and a high level signal is output from the OR circuit 65 and input to the controller 31. As a result, the controller 31 causes the electromagnetic contactor M to
The contact 42a of C2 is short-circuited, and the contact 4 of the electromagnetic contactor MC3
Open 3a. As a result, the commercial power supply 32 is connected to the motor 36 via the bypass 44 without passing through the inverter 30, and commercial operation is performed.

Other configurations, operations and effects are similar to those of the first embodiment.

[0038]

As described above, according to the ventilation amount control device of the present invention, the commercial power source is connected to the fan via the inverter and the commercial power source is not connected to the fan depending on the state of the inverter. Since the state in which the fan is connected is automatically switched, it is possible to automatically switch to the commercial operation when the fan is operated at the rated value or when the inverter malfunctions.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing wiring of an inverter, a power supply, and a fan in a ventilation amount control device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a schematic configuration of an inverter in FIG.

FIG. 3 is an explanatory diagram showing wiring of an inverter, a power supply, and a fan in the ventilation amount control device according to the second embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a ventilation volume control device according to a second embodiment of the present invention.

FIG. 5 is an explanatory diagram showing an example of the configuration of a ventilation system.

FIG. 6 is an explanatory diagram showing wiring of an inverter, a power supply, and a fan in a conventional ventilation system.

[Explanation of symbols]

 14A Exhaust fan 14B Air supply fan 22 Gas meter 30A, 30B Inverter 31 Controller 32 Commercial power supply 36 Motor 41a, 42a, 43a Electromagnetic contactor contact 41b, 42b, 43b Electromagnetic contactor coil

Claims (5)

[Claims] 1. An inverter for converting the frequency of a commercial power source to output to a fan for ventilating a kitchen room, a detection means for detecting a combustion gas amount of cooking equipment in the kitchen room, and a detection means for detecting this. Control means for controlling the output frequency of the inverter according to the amount of burned gas, and a state in which the commercial power source is connected to the fan via the inverter and the commercial power source is not connected to the fan depending on the state of the inverter. And a switching means for automatically switching between the state of being connected to the ventilation amount control device and the ventilation amount control device. 2. The switching means changes from a state in which the commercial power source is connected to the fan via the inverter to a state in which the commercial power source is connected to the fan without passing through the inverter when the output frequency of the inverter reaches a predetermined frequency. The ventilation volume control device according to claim 1, wherein the ventilation volume control device is automatically switched to. 3. The switching means automatically switches from a state in which the commercial power source is connected to the fan via the inverter to a state in which the commercial power source is connected to the fan without passing through the inverter when the inverter is abnormal. Claim 1
Ventilation control device described. 4. The first switching device is provided between the inverter and the fan, and operates according to an output signal of a control circuit in the inverter, and a commercial power supply and a fan not via the inverter. 4. A detour for connecting to and a detour, and a second electromagnetic contactor provided on the detour and operating according to an output signal of a control circuit in the inverter. Ventilation control device described in. 5. The switching means includes a first electromagnetic contactor provided between the inverter and the fan, a bypass line connecting the commercial power source and the fan without the inverter, and a bypass line provided in the bypass line. A second electromagnetic contactor, and electromagnetic contactor control means for operating the first electromagnetic contactor and the second electromagnetic contactor according to an output signal of a control circuit in the inverter. The ventilation volume control device according to any one of claims 1 to 3.