JP3079426B2 - AC motorized valve or gate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an AC motor-operated valve or gate used to open and close various pipes and various water channels.

[0002]

2. Description of the Related Art Conventionally, various pipes, for example, water pipes, sewage pipes, various pipes for chemical industry processes, gas pipes, air pipes, steam pipes, etc., have valves (for example, butterfly valves, sluices) for opening and closing them. Valves, funnel valves, ball valves, etc.).

Conventionally, various waterways, for example, rivers, irrigation canals, drainage channels (including open and dark) are provided with gates for opening and closing them.

[0004] Opening and closing of these valves or gates is performed by
This is performed by applying an AC voltage to an AC motor mounted on a valve or a gate. Specific drive control devices include the following.

(1) A device that opens and closes a valve or a gate at a substantially constant speed by applying an alternating current having a constant frequency to an AC motor.

(2) A device that repeatedly stops inching and operates the valve slowly at an opening where the flow rate changes greatly with respect to a change in the valve opening in order to reduce the temporal change rate of the flow rate.

(3) In a valve driven by an AC motor controlled by an inverter, a device that determines an inverter frequency for each opening section and controls an opening / closing speed.

[0008]

However, the above (1)
Device that opens and closes the valve or gate at a constant speed,
(2) Even if the valve or gate has two types of opening and closing speeds, the output of the AC motor has sufficient margin, and in fact, the opening and closing of the valve or gate is much slower as a whole compared to the capacity of the AC motor. It was done. For this reason, the time required for opening and closing is long, and, for example, the reverse flow rate of the fluid flowing in the pipe has increased. In the case of gates, there are many large facilities,
Opening and closing the doors takes a long time, and it is often the case that an operator needs to monitor on the spot until the opening and closing are completed. Therefore, if the opening and closing speed is slow, the workability is extremely deteriorated.

If the opening / closing speed of the valve or the gate is increased to solve the above-mentioned inconvenience, a transient phenomenon such as water hammer or surging at the gate may occur in a region near the fully closed state of the valve.

Further, in a device for controlling the opening / closing speed of a valve or a gate by setting an inverter frequency for each opening degree like the valve or the gate of the above (3), it is necessary to open and close the valve or the gate. Since the torque varies greatly depending on the opening,
It was difficult to set the actual opening / closing speed of the valve or gate to a predetermined appropriate speed simply by setting the inverter frequency constant for each opening section.

The present invention has been made in view of the above points, and an object of the present invention is to appropriately drive a valve or gate at an appropriate valve or gate opening / closing speed according to the opening degree of the valve or gate. To provide an AC motorized valve or gate.

[0012]

SUMMARY OF THE INVENTION To solve the above problems, the present invention provides a valve or gate, an AC motor driving the valve or gate, an inverter of the AC motor, and an opening / closing speed of the valve or gate. An AC motor-operated valve or gate provided with an opening / closing speed detecting means to be sought and an inverter control unit for increasing or decreasing the inverter frequency of the inverter so that the opening / closing speed becomes the opening / closing speed specified for each valve or gate opening section. Was configured. Also, the present invention provides the opening / closing speed detecting means, an opening degree detecting means for detecting an opening degree of the valve or gate, and an opening / closing speed of the valve or gate based on a time change rate of an opening degree signal from the opening degree detecting means. And an opening / closing speed calculating means for sequentially calculating. In the present invention, the inverter is mounted on a valve or gate drive mechanism including the AC motor.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram of an AC motor-operated valve to which the present invention is applied. As shown in the figure, a valve 10 of an AC motor-operated valve is mounted in a pipeline 5 so as to open and close the pipeline 5. The valve 10 is provided with a drive mechanism 20 including an AC motor M and a transmission mechanism T for opening and closing the valve, and an inverter device 30 for controlling the rotation speed of the AC motor M.

The valve 10 has a structure in which the pipeline 5 is opened and closed by an AC motor M and a transmission mechanism T. In this embodiment, a sluice valve is used.

In this embodiment, as the AC motor M, a torque motor having a performance of generating a maximum torque in a restricted state is used.

The drive mechanism 20 for the valve 10 includes a valve 1
A valve opening detecting means 11 for detecting a valve opening of 0 is attached. As the valve opening detecting means 11, for example, a potentiometer, a celsin or the like is used.

FIG. 2 is a diagram showing an example of the configuration of the inverter device 30. As shown in FIG. The inverter device 30 includes an inverter 40, an inverter control unit 50, and an operation panel 70 used to input a desired input from the outside.

The inverter control unit 50 includes at least a processing device 51 and a storage device 53. The inverter control unit 50 includes a valve opening signal input from the valve opening detecting means 11, a monitor voltage value of an input voltage input from the converter 80 to the inverter 40, and a signal from the inverter 40 to the AC motor M. A monitor current value of an output current to be output, an input signal from the operation panel 70, and the like are input.

On the other hand, the storage device 53 stores various control programs and various control data executed by the inverter control unit 50.

The inverter control unit 50 variably controls the inverter frequency applied from the inverter 40 to the AC motor M to thereby control the valve opening / closing speed of the valve 10 by the AC motor M (the rotation speed of the drive shaft of the valve). In this case, the inverter control unit 50 calculates the opening / closing speed of the valve 10 based on the time rate of change of the valve opening signal from the valve opening detection means 11, and calculates the opening / closing speed of the valve 10. The opening and closing speed of the valve (directly, the rotation speed of the drive shaft of the AC motor M) is controlled by increasing or decreasing the inverter frequency so that the opening / closing speed becomes a preset opening / closing speed (set rotation speed). The preset opening / closing speed of the valve is determined by the valve 10
In this embodiment, the set rotation speed (the set rotation speed of the drive shaft per unit time, that is, the set rotation speed, which is V1, 3 which is equivalent to the opening / closing speed.
At 0 to 100%, the set rotation speed V2 (where V1 <V2)
And

As shown in FIG. 3, the smaller the valve opening of the sluice valve 10 is, the higher the torque is required to rotate the sluice valve 10, but by setting the opening and closing speed of the valve 10 as described above. The valve opening at which the flow rate changes greatly and the load torque increases, that is, the valve 10 opens and closes slowly in the range of 0 to 30%, and the valve opening degree at which the flow rate changes and the load torque decreases, that is, the valve opening degree In the range of 30 to 100%, the valve 10 can be controlled so as to open and close quickly.

Hereinafter, the contents of the above control will be described with reference to schematic control flowcharts shown in FIGS. That is, first, when a signal for opening or closing the valve 10 is input to the inverter control unit 50 shown in FIG. 2, the mode is set to “frequency UP mode” as an initial setting in FIG. The number of rotations per time (hereinafter the same) is set to 0 (step 1).

Next, the current opening of the valve 10 is obtained from the valve opening signal from the valve opening detecting means 11, and the set number of revolutions corresponding to the opening is read from the storage device 53 (step 2).
That is, in the case of this embodiment, the set rotation speed V1 is read if the opening is 0% or more and less than 30%, and the set rotation speed V2 is read if the opening is 30% or more and 100% or less.

Next, the set rotational speed is compared with the current rotational speed (step 3). If the set rotational speed is larger, the rotational speed UP control shown in FIG. Increase (step 4) and return to step 2.

On the other hand, if the set number of revolutions is smaller in step 3, the opening / closing speed of the valve 10 is reduced by performing the number of revolutions DOWN control shown in FIG. .

In step 3, if the set speed and the current speed are the same, the operation at the current frequency is continued (step 7), and after the current speed is calculated (step 8), the process returns to step 2.

Here, in order to measure the current rotational speed of the valve 10, as shown in FIG. 5, the valve opening signal from the valve opening detecting means 11 is sequentially inputted to thereby control the valve 10 per unit time. The change in the opening is measured (step 1), the number of revolutions is calculated from the change in the degree of opening, and this is set as the current number of revolutions (step 2).

Next, in the rotation speed UP control shown in FIG. 6, first, the current rotation speed is retracted to the old rotation speed (step 1). Next, it is determined whether or not the current frequency is in the "frequency UP mode" (step 2). If the current frequency is the "frequency UP mode", the output frequency is increased by a predetermined value (step 3). Is measured (step 4). If the current rotational speed is higher than the old rotational speed, the "frequency UP mode" is maintained (steps 5 and 6), and if the current rotational speed is lower than the old rotational speed. Is switched to the "frequency DOWN mode" (steps 5, 7).

On the other hand, in step 2, "frequency D
In the case of the "OWN mode", the output frequency is lowered by a predetermined value (step 8), and then the current rotational speed is measured (step 9). If the current rotational speed is higher than the old rotational speed, the "frequency DOWN" Mode "(steps 10 and 11), and if the current rotational speed is lower than the old rotational speed, the mode is switched to the" frequency UP mode "(steps 10 and 12).

Next, in the rotational speed DOWN control shown in FIG.
Contrary to the rotational speed UP control, first, the current rotational speed is retracted to the old rotational speed (step 1), and then it is determined whether or not the current frequency is in the “frequency UP mode” (step 2). In the case of the "frequency UP mode", the output frequency is increased by a predetermined value (step 3), the current rotation speed of the valve 10 is measured (step 4), and if the current rotation speed is lower than the old rotation speed,
Leave "frequency UP mode" (steps 5 and 6),
If the current rotational speed is higher than the old rotational speed, the mode is switched to the "frequency DOWN mode" (steps 5 and 7).

On the other hand, in step 2, the "frequency D
If the "OWN mode" is set, the output frequency is lowered by a predetermined value (step 8), the current rotational speed is measured (step 9), and if the current rotational speed is smaller than the old rotational speed,
Leave "frequency DOWN mode" (step 10,
11) If the current rotational speed is higher than the old rotational speed, switch to the "frequency UP mode" (step 1)
0,12).

As described above, according to the present invention, the opening / closing speed (rotational speed of the drive shaft) is calculated from the change in the opening of the valve 10, and the opening / closing speed is set to a predetermined optimal set opening / closing speed (set rotation speed). Since the inverter frequency is sequentially changed so as to satisfy the following condition, the valve 10 can be set to a desired set opening / closing speed (set rotation speed) more accurately than control in which the inverter frequency is simply set for each valve opening section. ) Can be set and maintained.

In the case of the above embodiment, the water hammer can be prevented by reducing the opening / closing speed of the valve 10 when the load torque is large and the opening degree is 0% to 30%. On the other hand, the opening degree 30 with a small load torque
% Or more, by increasing the opening and closing speed of the valve 10,
The opening and closing time of the entire valve 10 can be reduced.

FIG. 8 is a schematic structural view of an AC electric gate to which the present invention is applied. This embodiment is different from the embodiment shown in FIG. 1 in that a drive mechanism 20 to which an inverter device 30 is attached is configured to vertically drive a gate 80 that opens and closes a river or a waterway K.

That is, the gate 80 is installed in a river, a waterway or the like K, and operates so as to open and close the river, waterway, or the like K by descending and rising. The fully opened state of the gate 80 is shown in FIG.
As shown by the dotted line L at the lower end of the gate 80, the water level of the river K or the waterway K is raised by the rise of water, etc., so that it is fully opened even at the maximum water level. Have been. When the lower end of the gate 80 is underwater, the drive resistance is large, so that the gate 80 is operated slowly. When the lower end of the gate 80 is above the water surface, the drive resistance is reduced, so that the inverter is operated quickly. Increase or decrease 30 inverter frequencies. The operation method of the inverter device 30 is the same as that of the valve.

That is, in the case of a valve, the valve opens and closes slowly when the valve opening is in the range of 0 to 30%, and opens and closes quickly when the valve opening is in the range of 30 to 100%. It opens and closes slowly in the degree range P, and the opening degree range Q above the water
Then you open and close quickly.

There are various types of means for moving the gate 80 up and down, such as a rack type, a wire rope winch type, and a spindle type.
However, any type may be used as long as the gate is opened and closed using the AC motor M as a drive source. In this embodiment, the boundary of whether the lower end of the gate 80 is underwater at the normal water level is set in advance, and the opening / closing speed of the gate 80 is increased or decreased depending on whether the lower end of the gate 80 is above or below the boundary. However, the opening / closing speed may be changed at other positions as needed. The opening of the gate 80 may be obtained by another opening detection sensor other than the opening degree detecting means 11. Alternatively, the current actual water level may be obtained by a sensor, and the opening / closing speed of the gate 80 may be changed using this water level position as a boundary.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and for example, the following various modifications are possible. The valve is not limited to the one having the above-described structure, and may be applied to various other valves such as a butterfly valve, a funnel valve, and a ball valve. The gate can also be applied to other various structures.

In the above embodiment, the opening degree of the valve is set to 0 to 30.
% And 30 to 100%, the set rotation speed is set for each of the opening sections. However, it goes without saying that the number of opening sections to be divided may be three or more. The same applies to the case of a gate.

In the above embodiment, the opening / closing speed of the valve or the gate is determined by calculating the detection signal from the valve / gate opening detecting means 11 in the inverter control section 50 (that is, the valve or the gate). The opening / closing speed detecting means of the valve or the gate is calculated by means of the opening detecting means 11 and the means for calculating the opening / closing speed of the valve or the gate from the detection signal of the opening detecting means 11 (corresponding to the rotational speed measurement flow shown in FIG. 5). However, the opening / closing speed of the valve or the gate can also be obtained by various other methods. That is, as shown in FIG. 9, for example, the opening / closing speed detecting means 85 of the valve 10 such as an encoder is attached in place of the opening detecting means 11 of FIG. 1, and thereby the opening / closing speed of the valve 10 is directly obtained. This eliminates the need to calculate the opening / closing speed. The opening of the valve 10 may be obtained by the opening / closing speed detecting means 85 or may be obtained by another sensor. Needless to say, this configuration can also be applied to the gate 80. That is, as long as an opening / closing speed detecting means (including one obtained by calculation) for obtaining the opening / closing speed of the valve or the gate is provided, the opening / closing speed detecting means may be of any configuration, either directly or by calculation.

[0041]

As described above in detail, according to the present invention, a valve or a gate can be driven properly and smoothly at an appropriate opening / closing speed of the valve or the gate in accordance with the opening of the valve or the gate. In particular, in the present invention, the opening / closing speed of the valve or gate is obtained, and the inverter frequency is sequentially changed so that the opening / closing speed becomes a predetermined optimal set opening / closing speed. Compared to the case where the inverter frequency is set for each section, the actual opening / closing speed of the valve or gate can be set and maintained more accurately and quickly, and the operation of the valve or gate can be optimized and smoothed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an AC motor-operated valve to which the present invention is applied.

FIG. 2 is a diagram illustrating a configuration example of an inverter device 30.

FIG. 3 is a characteristic diagram of a valve opening-load torque of the sluice valve 10;

FIG. 4 is an overall schematic control flowchart of an AC motor-operated valve.

FIG. 5 is a flowchart of a rotation speed measurement.

FIG. 6 is a flowchart of a rotational speed UP control.

FIG. 7 is a flowchart of a rotational speed DOWN control.

FIG. 8 is a schematic configuration diagram of an AC electric gate to which the present invention is applied.

FIG. 9 is a schematic configuration diagram of an AC motor-operated valve according to another embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 valve 11 valve opening detection means 40 inverter 50 inverter control unit M AC motor 80 gate

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-47308 (JP, A) JP-A-4-296271 (JP, A) JP-A-4-47309 (JP, A) JP-A-58-1983 217876 (JP, A) JP-A-6-337079 (JP, A) JP-A-10-150795 (JP, A) Patent 2631635 (JP, B2) Patent 2641687 (JP, B2) JP-B-3-16547 (JP) , B2) Tokiko Hei 3-14106 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16K 31/00-31/11 F16K 37/00

Claims (3)

(57) [Claims] A valve or a gate; an AC motor driving the valve or the gate; an inverter of the AC motor; an opening / closing speed detecting means for determining an opening / closing speed of the valve or the gate; An AC motor-operated valve or gate, comprising: an inverter control unit that increases or decreases the inverter frequency of the inverter so that the opening / closing speed specified for each opening section is obtained. 2. An opening / closing speed detecting means for detecting an opening degree of the valve or gate, and an opening / closing speed of the valve or gate based on a time change rate of an opening signal from the opening degree detecting means. 2. An AC motor-operated valve or gate according to claim 1, further comprising an opening / closing speed calculating means for sequentially calculating. 3. The AC motor-operated valve or gate according to claim 1, wherein the inverter is attached to a valve or gate drive mechanism including the AC motor.