JP2531841B2 - Valve opening control device for ball valves for air conditioners - Google Patents

Description

TECHNICAL FIELD The present invention relates to a valve opening control device for a ball valve for an air conditioner.

(B) Conventional technology Conventionally, a ball valve that has a spherical valve body having a flow passage formed in the center is housed inside a valve casing having an inflow port and an outflow port, and is opened and closed by rotating the spherical valve body. Yes,
To adjust the valve opening of such a valve, there are two-position control in which the valve is fully opened or fully closed, and proportional control in which the valve opening is adjusted steplessly. In the proportional control, a spherical valve element and a servo motor are used. A delicate and smooth control is enabled by feedback-controlling the rotation of the spherical valve body by interlocking with a sensor such as a potentiometer for detecting the valve body rotation angle.

(C) Problems to be Solved by the Invention However, in the proportional control, delicate and smooth control is possible, but since the ball valve body is provided with a sensor such as a potentiometer as described above, the outer shape becomes large. However, there was a drawback that it became expensive.

Therefore, a ball valve was developed in which the spherical valve body was linked to a synchronous motor and the operation of the motor was controlled by a control device with a built-in microcomputer. The data is stored in the microcomputer, and the synchronous motor is supplied with the driving time corresponding to the desired rotation angle of the spherical valve body or the alternating current of the wave number for driving the motor to rotate the spherical valve body to the desired angle. I am trying to let you.

Then, the present position data is reset by adding or subtracting the desired angle to or from the present position data.

However, due to uneven friction between the spherical valve body and the packing, uneven resistance of the speed reduction mechanism interposed between the synchronous motor and the spherical valve body, etc., the current position data of the spherical valve body stored by the microcomputer is stored. Every time a slight error occurs between the true current position and the opening / closing operation of the spherical valve body, the above error is accumulated, and the true current position of the spherical valve body and the current position stored by the microcomputer. There is a risk that a large error will occur between the data and the operation of the air conditioner.

(D) Means for Solving the Problems In the present invention, a spherical valve body having a flow path formed in the central portion is housed inside a valve casing having an inflow port and an outflow port, and by rotating the spherical valve body, In a ball valve that opens and closes, a spherical valve body is linked to a synchronous motor,
It is intended to provide a valve opening control device for a ball valve for an air conditioner, characterized in that the rotation angle of the motor is controlled by a control device having a microcomputer built therein. In the present invention, a spherical valve body having a flow path formed in the central portion is housed inside a valve casing having an inflow port and an outflow hole, and a synchronous motor is interlockingly connected to the spherical valve body to rotate the motor. In a ball valve configured to control the movement angle by a control device with a built-in microcomputer, the ball valve is equipped with a closing side limit switch that detects the fully closed state of the spherical valve element, and the output of the switch The present invention provides a valve opening control device for a ball valve for an air conditioner configured to reset the current position data of the spherical valve body stored by the microcomputer.

In addition, an interrupt counter for counting the number of opening and closing operations of the spherical valve element is set in the microcomputer, and the spherical valve element is driven in the closing direction to be fully closed at every predetermined number of opening and closing operations of the spherical valve element. The current position data of the spherical valve body stored by the microcomputer is reset by the output of the side limit switch, and the driving time calculated by the microcomputer from the opening / closing operation amount of the spherical valve body and the valve opening / closing speed is a predetermined time. Is also added to correct the inertial force of the armature of the synchronous motor and the spherical valve body, and the decrease in the operating amount due to the frictional force between the spherical valve body and the packings on the inflow and outflow sides.

(E) Operation According to the present invention, since the synchronous motor rotates in synchronization with the phase of the alternating current that drives the motor, the rotation angle of the motor is calculated by multiplying the frequency of the alternating current by the driving time. Can be controlled.

By connecting the synchronous motor to the spherical valve body in an interlocking manner, the microcomputer with a built-in control device can drive the synchronous motor from the frequency of the alternating current and the desired rotation angle of the spherical valve body. Then, the ball valve can be rotated by a desired angle by driving the synchronous motor for this time.

The current position of the spherical valve body can be grasped by integrating a numerical value obtained by multiplying the rotation direction of the motor by the drive time, and this integrated value is stored in the memory of the microcomputer as the current position of the spherical valve body. While storing, the driving time is calculated from the difference between the present position and the desired position and the synchronous motor is driven to rotate the spherical valve element to the desired position to open and close the ball valve as desired. The valve opening can be controlled.

For setting the initial position of the spherical valve element, for example, at the time of starting operation and periodically thereafter, the spherical valve element is excessively driven to forcibly press the spherical valve element to the fully open or fully closed position. There are means such as using the position of as a reference.

In the present invention, the current position data of the spherical valve body stored by the microcomputer is reset by the output of the closing side limit switch that detects the fully closed state of the spherical valve body, so that the spherical valve body is closed every time. Moreover, the true current position of the spherical valve body and the current position data stored by the microcomputer can be made to coincide with each other, and the accumulation of the above-mentioned error is prevented.

Further, when the interrupt counter that counts the number of opening and closing operations of the spherical valve body set in the microcomputer counts a predetermined number of times, the spherical valve body is driven in the closing direction to be fully closed,
The output of the limit switch resets the current position data of the spherical valve body stored by the microcomputer, so that the true current position of the spherical valve body and the current position data stored by the microcomputer are made to coincide with each other to accumulate the error. Can be prevented. After that, by rotating the spherical valve element to a predetermined position based on the reset position data, the air conditioner can be operated normally.

Also, the driving time of the synchronous motor calculated by dividing the desired opening / closing operation amount by the opening / closing speed of the spherical valve element, the inertia force of the armature of the synchronous motor and the spherical valve element, and the frictional force between the spherical valve element and the packing. By adding the time for correcting the decrease in the operation amount due to, the spherical valve element can be accurately opened and closed by the desired opening and closing operation amount, and the current position data stored by the microcomputer is also accurate.

(F) Effect As described above, since a commercially available synchronous motor can be used to drive the spherical valve body of the ball valve, the cost of the valve device can be reduced.

Also, since the valve position sensor is not required, the valve device is downsized, and it is easy to install it in a narrow inside such as a fan coil unit. Furthermore, since the structure is simple, there are few failures and maintenance work is easy. There is an effect that.

In particular, the current position data of the spherical valve body stored by the microcomputer is reset each time the spherical valve body is fully closed, or the current position data is reset each time the spherical valve body is opened and closed a predetermined number of times. Or, correct the opening / closing operation amount to the desired opening / closing operation amount by compensating for the decrease in the operation amount due to the inertial force of the synchronous motor armature and the spherical valve body or the frictional force between the spherical valve body and the packing. effective.

(G) Embodiment An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view of a ball valve (V). The valve (V) is composed of a valve portion (1) and a synchronous motor (M). The synchronous motor (M)
Rotates in synchronism with the phase of the alternating current that drives the motor (M). Therefore, the rotation angle of the motor can be controlled by the frequency of the alternating current and the driving time.

(2) is a valve casing, (3) is an inlet, (4) is an outlet, (5) is a spherical valve element, (6) is a flow path having a circular cross section formed in the central portion of the spherical valve element (5), (7) is an engaging groove formed on the upper surface of the spherical valve body (5), (8) is a lower end formed with a protrusion fitting into the engaging groove (7), and the upper end is the synchronous motor (M). Valve stem connected to the output shaft of
(9) is an O-ring fitted onto the valve stem, and (10) is an inflow side packing, which forms a substantially triangular opening (11) as shown in FIG. The opening area through which the fluid can flow due to the matching of the opening (11) with the flow path (6) of the spherical valve body (5) is proportional to the rotation angle of the spherical valve body (5). (12) is the packing on the outflow side.

In such a ball valve (V), the rotation angle of the synchronous motor (M) is proportional to the frequency of the alternating current driving the motor (M) and the drive time, and the flow rate is equal to the rotation angle of the valve (V). Since it is proportional, the flow rate is proportional to the product of the frequency and the driving time.

In this embodiment, a 24-pole synchronous motor (M) is
It is decelerated to 1/150 and linked to the spherical valve body (5),
When the driving AC is 50Hz, fully closed → fully open or vice versa 90se
c, 60Hz, fully closed → fully open or vice versa 7.5se
c is required.

The load on the synchronous motor (M)
The armature of the motor (M) and the inertial force of the spherical valve body (5), the spherical valve body (5) and the packings (1) on the inflow and outflow sides.
There is a frictional force between 0) and 12), and when the spherical valve body (5) starts to rotate, both the inertial force and the frictional force act as resistance of the synchronous motor (M).
Step out for 0.2 sec occurs. However, when the rotation of the spherical valve body (5) is stopped, the inertial force and the frictional force act to cancel each other, so that the spherical valve body (5) has a characteristic of immediately stopping without a time lag.

FIG. 3 is a circuit diagram showing a configuration of the control device (C). The control device (C) has a microcomputer (20) provided with an output port for a valve opening signal and an output port for a valve closing signal on the output side. ) And a drive circuit (21), and the drive circuit (21) amplifies each of the above signals, and a power transistor (22) (23) and each power transistor (22).
It is composed of relays (24) and (25) that operate with the output of (23).

(26) (26) is a power transistor (22) (23) protection diode, (27) is a phase advancing capacitor, (28) is a single phase, AC power supply for supplying 100V AC to the synchronous motor (M) is there.

(29) is a closing side limit switch, which is arranged at a position where it is turned off when the spherical valve body (5) rotates in the valve closing direction and slightly goes beyond the fully closed state. The OFF signal of 29) stops the operation of the synchronous motor (M) to prevent the overstroke of the spherical valve body (5), and the signal is sent to the microcomputer (2
0) to reset the current position of the spherical valve body (5) stored in the memory of the computer (20).

(30) is an open side limit switch, which is turned off when the spherical valve body (5) rotates in the valve opening direction and slightly goes beyond the fully opened state to prevent the overstroke of the spherical valve body (5). I am trying to do it.

FIG. 4 is an explanatory diagram of an embodiment in which the ball valve (V) according to the present invention is applied to adjust the flow rate of the heat medium of the air conditioning system (B).

(51) is a heat source with a built-in boiler and chiller,
In the case of heating, hot water controlled to a constant water temperature from the boiler,
In the case of cooling, a chiller is used to send cold water whose temperature is controlled to a constant temperature to a coil (53) of a fan coil unit (52) while controlling a flow rate with the ball valve (V) as a heat medium at a predetermined pressure. There is.

The coil (53) has a heat exchange function, and the fan (5
The air in the room is sucked in by 4), heated or cooled by the heat medium flowing in the coil (53), and blown out into the room.

(D) is a power source and a control unit for controlling the following devices.

Reference numeral (55) is a fan controller, which is provided between the fan (54) and the microcomputer (20).

(56) is a temperature sensor for measuring the temperature of the heat medium at the outlet of the heat medium coil (53), and is a frequency converter (57)
It is connected to the microcomputer (20) via.

Reference numeral (58) is a power supply rectifier, which supplies direct current to the microcomputer (20).

(E) is an operation unit, (59) is a start / stop button, (60)
(61) is the setting button, (62) is the automatic / manual switch button,
(63) is a heating / cooling switching button, (64) is a temperature sensor for measuring the indoor temperature, (65) is a set temperature indicator, and
Each is connected to a microcomputer (20).

In the air conditioning system (B), the drive circuit (21) is arranged on the control section (D) side and the microcomputer (20) is arranged on the operation section (E) side.

Next, the operation of the air conditioning system (B) will be described with reference to FIGS.

FIG. 5 is a flowchart of the main routine (70), from the start / stop button (59) to the microcomputer (20).
When the start (71) signal is input to the, the program is initialized (72) and the ball valve (V)
Whether the frequency of the AC power supply (28) connected to is 60Hz or 50
It is detected whether it is Hz (73), the ratio of the valve opening and the drive time corresponding to each frequency is calculated and set in the register (74) (75), and the interruptable state of other control subroutines is set. Yes (76).

FIG. 6 is a flow chart of the manipulated variable calculation subroutine (80), which interrupts the main routine (70) about every 10 msec, and FIG. 7 is a flow chart of the valve drive subroutine (100), 50 msec. The main routine (70) is interrupted at the cycle of.

First, the operation amount calculation subroutine (80) in FIG. 6 will be described.

That is, when this subroutine (80) is activated (81) by an interrupt signal generated about every 10 seconds, first, the input counter, which will be described later, is cleared (87) and the start / stop button (59) of the operation unit (E) is used. ) Output status, set temperature from the setting buttons (60) (61) (82), clear the time counter (83), and determine whether the fan coil unit (52) has already started ( 84) If not started (OFF), drive the synchronous motor (M) in the fully closing direction to fully close the spherical valve body (5) (85), and set this position as the reference for operating the spherical valve body. At the same time as setting it to the position, the interrupt counter described later is cleared (86), and the process returns to the main routine (88).

In step (85), the synchronous motor (M) is driven in the closing direction for a time longer than the time required from full opening to full closing to ensure that the spherical valve body (5) is at any position. The spherical valve body (5) can be fully closed, and when the spherical valve body (5) is rotated to the fully closed position, the closing side limit switch (29) is turned off. Cut at (29).

Also, in step (84), if the fan coil unit (52) has already been started, it turns ON, the interrupt counter is counted up (89), and the count number of the interrupt counter is 50.
If it is, jump to the step of 90Y, (85), if it is not 50, 90N, calculate the average value of the deviations from the deviation total value described later and the deviation input count of the input counter (91),
Calculate the new opening of the ball valve (V) from the same average value (9
2) Calculate the operation amount of the ball valve (V) by subtracting the current opening from the new opening (93).

If the manipulated variable is positive (negative) (94), the drive time in the open (closed) direction is calculated (95) (96), and the process returns to the main routine (88).

It should be noted that the above-mentioned 0.2 sec is added to the calculation of the drive time to compensate for the decrease in the rotation angle due to step-out.

The driving direction and the driving time of the ball valve (V) calculated in this way are passed to the valve driving subroutine (100) shown in FIG. 7, and the synchronous motor ( Drive M).

That is, this valve drive subroutine (100)
When the valve drive subroutine (100) is started (101), the drive direction and drive time of the ball valve (V) calculated by the operation amount calculation subroutine (80) are read ( 102), first, it is judged whether or not the driving direction and the driving time mean full closing (103), and if it means full closing,
Y, output the fully closed drive to the synchronous motor (M) (10
4) Input the current temperature in the room from the temperature sensor (64) (105), count up the input counter (106), add up the deviation of the current temperature from the set temperature (107), and return to the main routine ( 115).

Further, in step (103), if it does not mean a fully closed state, N is determined, and the driving direction is determined (108). If it is in the open direction, O is determined, and it is determined whether the driving time ≦ time counter is satisfied. (109) If satisfied, the synchronous motor (M) is driven in the opening direction (110), the time counter is incremented, and the steps (111) and (105) are performed.

If the drive time ≦ time counter is not satisfied in step (109), the synchronous motor (M) is stopped (112) and the process returns to the main routine.

If the driving direction is the closing direction in step (108), it is determined whether the driving time ≦ time counter is satisfied if the driving direction is S (113). If the driving time is satisfied, the synchronous motor (M) is driven in the closing direction. Then (114), the time counter is incremented (111), and the process goes to step (105).

By the above control operation, the heat medium having a flow rate proportional to the deviation between the set temperature and the present room temperature is caused to flow through the coil (53) of the fan coil unit (52) to converge the room temperature to the set temperature, and The state can be retained.

Especially, as described above, the ball valve (V) is fully opened.
→ It takes 7.5 to 9 seconds to fully close, but by operating it at intervals of about 10 seconds, there is no need to input a new drive signal during operation of the valve (V) and change the operation amount. The valve must be stopped after every operation, meaningless operation can be prevented, and the durability of the valve (V) can be improved.

Generally, the response of air conditioning system is slow, so
A c-cycle operation is sufficient.

In addition, it is necessary to correct the influence of inertial force and frictional force on the driving time of the synchronous motor (M) calculated by calculation.
By adding 2 seconds, the ball valve (V) can be operated accurately.

When the operation of the ball valve (V) is repeated 50 times, the spherical valve body (5) is fully closed once and the position data in the memory is cleared to determine the position of the spherical valve body (5) associated with the operation. Since it is reset before the error with the position data is accumulated, the ball valve (V) can be accurately controlled.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional explanatory view of a ball valve according to the present invention, FIG. 2 is a view of packing as viewed from the direction of arrow I, FIG. 3 is an explanatory view showing a configuration of a control device, and FIG. Explanatory diagram showing the configuration of the system, FIGS. 5 to 7 are flowcharts of the air conditioning system control program. (C): Control device (V): Ball valve (M): Synchronous motor (2): Valve casing (3): Inlet port (4): Outlet port (5): Spherical valve body (6): Flow path (20): Microcomputer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Nishio 3351-8 Umi-cho, Kasuya-gun, Fukuoka Prefecture Umi factory Showa Iron Works Co., Ltd. Suwa Factory Co., Ltd. (56) Bibliography Shou 62-7794 (JP, U)

Claims (3)

(57) [Claims] 1. A spherical valve body (5) having a flow passage (6) formed in a central portion thereof is housed inside a valve casing (2) having an inlet (3) and an outlet hole (4). Spherical valve body (5)
In a ball valve (V) configured such that a synchronous motor (M) is interlocked with and a rotation angle of the motor (M) is controlled by a control device (C) having a microcomputer (20) incorporated therein. The ball valve (V) is provided with a closing side limit switch (29) for detecting the fully closed state of the spherical valve body (5), and the output of the switch (29) causes the microcomputer (20) to store the spherical shape. A valve opening control device for a ball valve for an air conditioner configured to reset the current position data of the valve body (5). 2. The microcomputer (20) is provided with an interrupt counter for counting the number of opening and closing operations of the spherical valve element (5), and the spherical valve element (5) is opened and closed every predetermined number of opening and closing operations of the spherical valve element (5). 5) is driven in the closing direction to be fully closed, and the current position data of the spherical valve body (5) stored in the microcomputer (20) is reset by the output of the closing side limit switch (29). The valve opening control device for a ball valve for an air conditioner according to claim 1. 3. The synchronous motor of the ball valve (V), wherein a predetermined time is added to the driving time calculated by the microcomputer (20) from the opening / closing operation amount and the opening / closing speed of the spherical valve body (5). (M) The armature and the inertial force of the spherical valve body (5) and the decrease in the operating amount due to the frictional force between the spherical valve body (5) and the packings (10) (12) on the inflow and outflow sides are corrected. The valve opening control device for the ball valve for an air conditioner according to claim 1.