JPH01295084A - Automatic valve - Google Patents

Abstract

PURPOSE:To surely close a valve unit, even when a difference is generated in calculation, by outputting to a piezoelectric actuator a number of pulses in a closing direction excessively above the required number of pulses by the calculation required for closing the valve unit. CONSTITUTION:An automatic valve is provided with a plunger P, clamping piezoelectric elements (e), (f) and stroke piezoelectric elements (g), (h). A valve unit 11 of the automatic value is actuated by a piezoelectric actuator moving the plunger P with a pulse-state control output from a control unit (c). When a valve opening signal is input to the control unit (c), a number of pulses excessively above the number of pulses, actuating the valve unit 11 from its position in the point of time inputting a valve closing signal to the closing position, is output.

Description

[Detailed description of the invention] (b) Industrial application field The present invention relates to automatic valves.

(b) Conventional technology Conventionally, there has been a piezoelectric actuator configured to move a plunger by repeatedly expanding and contracting a piezoelectric element using a pulse-like control output. A piezoelectric element for clamping is connected to the other end, the plunger is clamped by the piezoelectric element for clamping, the clamped plunger is moved by the piezoelectric element for stroke, and then the piezoelectric element for clamping is moved by the piezoelectric element for clamping. The plunger is moved by repeatedly releasing the stroke piezoelectric element and restoring the stroke piezoelectric element.

Since the stroke of the plunger is proportional to the voltage and number of pulses of the control output, by keeping the voltage of the control output constant and controlling the number of output pulses, the plunger can be moved the required distance. By omitting direct plunger position detection, so-called open-loop control is possible.

(C) Problems to be Solved by the Invention However, in open-loose plunger operation control, the position of the plunger that is the starting point of the control operation is
This is a calculated position obtained by counting the number of pulses output from the control device to the piezoelectric actuator, and may vary due to differences in load and operating characteristics due to differences in operating direction, fluctuations in control output voltage, slippage of plunger during clamping, etc. However, there is a problem that the calculated plunger position and the actual plunger position may deviate, and this deviation accumulates, making it impossible to operate accurately.

When such a piezoelectric actuator is used in an automatic valve of a hot water mixing device, it is not possible to accurately control the hot water temperature and the hot water flow rate, and in severe cases, a signal to stop the hot water tap may be sent to the control device.
That is, even if a valve closing signal is input, the automatic valve may not close completely, and the hot water may not be completely stopped.

Furthermore, in order to avoid such a situation, it is necessary to specially provide a position detection means using a microswitch or a pole IC, leading to an increase in the price of the device.

(d) Means for Solving the Problems The present invention provides a piezoelectric device that is provided with a plunger, a piezoelectric element for clamping, and a piezoelectric element for stroke, and that moves the plunger using a pulse-like control output from a control device. In an automatic valve whose valve body is actuated by an actuator, when a valve closing signal is input to the control device, the number of pulses required to operate the valve body from the position of the valve body at the time the valve closing signal is input to the closed position is It is an object of the present invention to provide an automatic valve characterized by being equipped with a control device that outputs an excessive number of pulses in the closing direction.

(e) Operation In this invention, when a valve closing signal is input to the control device, the valve body is closed from the calculated plunger position calculated by counting the number of pulses output to the piezoelectric actuator up to the point in time when the valve closing signal is input to the control device. By outputting an excess number of pulses in the closing direction to the piezoelectric actuator than the calculated number of pulses required to open the valve, even if there is a discrepancy between the calculated plunger position and the actual plunger position, the valve body can be held securely. The valve can be closed.

Then, by calibrating the pulse count number of the control device starting from the position of the plunger where the valve has been reliably closed as described above, the pulse count number is calibrated every time the automatic valve closes. The difference between the plunger position and the actual plunger position can be prevented from accumulating by 1A, and the valve body can be made to operate accurately.

Note that driving of the plunger due to excessive pulses output after the valve body closes can be absorbed by adjusting the clamping force of the piezoelectric element for clamping to cause the plunger to slip.

(F) Effect As mentioned above, the calculated plunger position is calibrated to the actual plunger position each time the automatic valve closes, so the deviation between the calculated plunger position and the actual plunger position does not accumulate. First, the automatic valve operates accurately, and when applied to an automatic valve such as a hot water mixing device, the hot water temperature and flow rate can be accurately controlled.

(G) Embodiment An embodiment of the present invention will be described in detail based on the drawings. Fig. 1 shows a hot water mixing device (B) to which the piezoelectric actuator driving method according to the present invention is applied, and the hot water mixing device (B) as an automatic valve. A hot water supply pipe and a water supply pipe are connected to the inlets of the side and water side flow rate adjustment valves m) [V2), respectively, and each valve (Vl) (V2
) are arranged to face each other and communicate with each other, and the flow rate ratio and the sum of the flow rates of hot water and water supplied from the hot water supply pipe and the water supply pipe are controlled by the hot water side and water side flow rate regulating valves (V1HV2). The temperature and flow rate are adjusted to maintain the set temperature and flow rate.

The hot water side and water side flow rate regulating valves (1, 11) (V2) have substantially the same configuration except that the fluids that pass therethrough are different for hot water and hot water, and are configured as follows.

That is, an inflow pipe f2)+2) is formed on the - side of the main body (1) and an outflow pipe (3) is formed on the other side, and the outflow pipe (3) is formed inside the intersection with the inflow pipe (2) (2). Extend it to the middle tube (3
The main valve Fi (4) (4) is formed on the end face of the main valve seat (
4) A diaphragm (5) + 5) is stretched over the upper end surface of the inflow pipe (2) (2) surrounding the outer periphery of (4), and a pilot valve a (6) is installed in the center of the diaphragm (5) (5). (6)
, orifices (7) (7) are provided on the same peripheral edge to communicate with the outflow pipe (3) and inflow pipe (2) (2), respectively, and the upper part of the diaphragm (5) + 5) is connected to the actuator mounting base. <8) (8) is closed to form a pressure chamber (gH9) between the base (8) [8) and the diaphragm f505).

Piezoelectric actuators ([) 1) (D2), which will be described later, are installed on the top surface of the actuator mounting base (8) (8), and the cylindrical plungers (P) (P) of the actuator + DI) (02) are installed. ) The valve body (11) + 11) extending from the pilot valve seat (6) (6) comes into contact with and separates from the pilot valve seat (6) (6) to operate the diaphragm (5) (5).
) (4) and the lower surface of the diaphragm (5) (5) are brought into contact with and separated from each other to open and close the hot water side and water side flow rate regulating valves (VIHV2).

As shown in FIG. 1, the piezoelectric actuators f01) (02) provided in the hot water side and water side flow rate regulating valves mHV2) are housed in a cylindrical casing (d) having front and rear walls (a) and (b). A cylindrical plunger (fP) is mounted concentrically and movably back and forth along the axis, and four piezoelectric elements (e), (f) ((
1) It is constructed by arranging a piezoelectric tissue assembly consisting of (h).

The piezoelectric element (c+) (h) is attached to the tip of the holder (C).

Further, (iHj) is a cantilever-like elastic bridge whose base end is fixed to the piezoelectric elements (q) and (h) and whose tip end extends toward the front and rear walls (a) and (b).

The tip of the elastic bridge (iNj) has piezoelectric elements (e) (f) attached to its outer circumferential surface, and brake shoes (k) (, ll) fixed to its inner circumferential surface. .

Of these piezoelectric elements (eHf) (g) and (h), piezoelectric elements (e) and (f) function as clamp members, and when the power is not turned on, the piezoelectric elements ((1) (h) )
is configured to retract when turned off.

That is, when the piezoelectric element (ELF) is energized, it contracts and acts in a direction to reduce its inner diameter, increasing the clamping force of the cylindrical plunger (P), and when it is not energized, it stretches and expands its inner diameter. It acts in the radial direction to reduce the clamping force of the cylindrical plunger (P).

On the other hand, the piezoelectric elements (g) and (h) are contracted in the axial direction on the cylindrical plunger (P) when not energized, and extend on the cylindrical plunger (P) when energized. The total length in the axial direction is increased.

The cylindrical plunger (P) controls the four piezoelectric elements (e), (f), (c+), and (h) by a control device (to be described later).
C), it can be moved in the axial direction.

Next, a cylindrical plunger CP) using an actuator having such a configuration and a valve body (1
The movement 1) will be explained with reference to FIGS. 2 to 1.

When a voltage is applied to the piezoelectric element f8) from a control device (C), which will be described later, according to a drive program, the cylindrical plunger (P) is clamped by acting in the direction of diameter reduction, as shown in FIG. While increasing the force, the voltage of the piezoelectric element (f) is released to expand the diameter of the piezoelectric element (f), thereby reducing the clamping force of the cylindrical plunger (P) by the piezoelectric element (f).

Next, as shown in FIG. 3, when a voltage is applied to the piezoelectric elements (q) and (h) to cause them to expand, the piezoelectric elements (f8) and (h) move in the direction of the arrow, and along with this, the piezoelectric elements (e) ) is larger than the clamping force of the piezoelectric element (f), the cylindrical plunger (P) also moves in the direction of the arrow by slipping on the clamping portion of the piezoelectric element (f).

Thereafter, as shown in Fig. 4, a voltage is applied to the piezoelectric element (f) to increase the clamping force of the cylindrical plunger (P), and then the voltage applied to the piezoelectric element fe) is released to move the cylindrical plunger (fe) in the direction of diameter expansion. When the clamping force of the cylindrical plunger (P) is reduced and the voltage applied to the piezoelectric element fq) (h) is released, the piezoelectric element (g) (h) shortens in the direction of the arrow.
The cylindrical plunger (P) further moves in the direction of the arrow.

Thereafter, by repeating the above operation, the cylindrical plunger (P) can be moved in a linear manner with a stroke on the μm order or sub-μm order, and the cylindrical plunger (P)
P) Various operating devices connected to the valve body (11) at the tip can be operated precisely.

Moreover, FIGS. 5 and 6 show the case where the hot water mixing device (B) is used in an automatic faucet (50) of a wash basin.
51) is the hand detection switch, (52) is the 0N10FF button, (54) is the discharge port, (55) and (56) are the operation unit (Q
) are temperature setting and flow rate setting buttons.

(53) is a temperature sensor, which detects the temperature of mixed hot water and controls the piezoelectric actuators ( 01) (D2) cylindrical plunger (P)fP)
The above-mentioned flow rate ratio and discharge amount are adjusted by advancing and retracting the valves, and the operation of the cylindrical granger (PNP) of each flow rate regulating valve (V1HV2) is performed in cooperation with the calculation by the control device.

Next, a control device (C) that controls the piezoelectric actuator (DI) (02) will be explained.

As shown in Fig. 7, the control device (C) includes a microphone 17 processor (15), a temperature sensor (53), a temperature setting button (55), a flow rate setting button (56), an 0N10FF
It consists of a button (52), an input interface (18) connected to a hand-sensitive switch (51), a memory (19) storing actuator control and drive programs, and an output interface (20) connected to a piezoelectric actuator CDIHD2). 0N10FF
If the button (52) is pressed or the hand sensing switch (51)
) senses a hand, the control device (C) sends a valve opening control output to the piezoelectric actuator (Ql) (02), and then, while the flow rate setting button (56) is held down, continues the same control output, and presses the same button (5).
6), the control output stops when released. Therefore, the flow rate of the automatic water faucet (50) can be adjusted depending on how long the button (56) is pressed.

In addition, the temperature of the discharged water is detected by a temperature sensor (53) and inputted to the control device f (C), and the temperature of the mixed hot water is determined based on the detection result of the sensor (53) by pressing the temperature setting button (55).
Calculate the flow rate ratio of the hot water side and water side flow rate adjustment valves m) (V2) so that the desired temperature set in
2) Output.

Additionally, if the 0N10FF button (52) is pressed while water is being spouted or the hand control switch (51) no longer senses a hand, the control device (C) will activate each piezoelectric element (e) (f) (g) fh.
) is provided with a pulse-like control output in the closing direction, and each flow rate regulating valve m) (V2) is automatically closed.

In particular, during the above control program, a hand-sensing switch (5
1) and the 0N10FF switch (52), and when a valve closing signal is input from the switch (52) to the control device fc), it is output to the piezoelectric actuator by the same time. From the calculated plunger position obtained by counting the number of pulses, calculate the calculated number of pulses required to close the hot water side and water side flow rate adjustment valves (Vl) (V2), and perform this calculation. To the above required number of pulses, assuming the deviation between the calculated plunger position and the actual plunger position, add the appropriate number of additional pulses to each piezoelectric element (e) (f) (c+) of the piezoelectric actuator.
)(h).

As mentioned above, an excessive number of pulses are output to the piezoelectric actuator, so the hot water side and water side flow rate adjustment valves (Vl) (V
Even after the valve 2) is closed, excessive pulses will be input to the same actuator, and the valve body (11) (11) will be driven in the closing direction even after the valve is closed. By adjusting the control output voltage to the piezoelectric element (ELF), the cylindrical plunger (P) and the brake shoe (k) (,
1! ) can absorb the drive caused by excessive pulses, preventing the valve body from being pressed by excessive force, and avoiding damage to the valve body.

In this way, each time the valve closing signal is input to the control device (C), the hot water side and water side flow rate regulating valves (vl) (■2)
The valve bodies (11) (11) of (11) are securely placed in the valve closing position, and then, using this valve closing position as a starting point, the control device fc)
By calibrating the memorized position of the cylindrical plunger (P), the discrepancy between the calculated plunger position and the actual plunger position is eliminated, the accumulation of the same discrepancy is prevented, and the hot water and water side flow rates are adjusted. The regulating valves (vl) (v2) can be operated accurately.

In addition, since the temperature and flow rate of the discharged water are determined by the ratio and sum of the flow rates on the hot water side and the water side, the openings of the hot water side and water side flow rate regulating valves (VIHV2) are determined in advance for the set temperature and set flow rate. The temperature is expressed as a mathematical expression or a numerical table and stored in the memory (19), and when input is received from the temperature setting button (55) and m M setting button (56), the microprocessor
The saucer (15) accesses the calculation or numerical table based on the above formula, immediately operates the hot water side and water side flow rate adjustment valve (VIHV2) based on this, and when the set temperature and flow rate are approached, the temperature sensor (53) ) based on the detected value of each valve (
VIHV2), which is extremely efficient compared to the conventional method, which waits for the input of the detected value from the temperature sensor (53) from the beginning and then controls each flow rate regulating valve m) (V2). Mixed hot water at a set flow rate at a set temperature can be discharged in a short time.

In addition, the temperature and pressure of hot water and water supplied to the hot water mixing device (B) vary depending on the installation status of the device (B) and the season, but they can be controlled by the above-mentioned calculation or access to the numerical table. The process of operation is stored as data in the memory (1), and this data is processed by a learning program stored in the memory (19) in advance to control the temperature and flow rate of the discharged water next time. The above formula or table can also be modified to provide more rapid and accurate control of the temperature and flow rate of the discharge water.

The embodiment of the present invention is configured as described above, and each time a valve closing signal is input to the control device, a control output in the closing direction is performed to the piezoelectric actuator with a number of pulses greater than the calculated required number of pulses. , Even in open-loose control, the valve body is ensured to close, the valve closing position is determined, and the calculated plunger position is calibrated using this position as a starting point, so that the calculated plunger position and the actual position can be This has the effect of preventing the accumulation of deviations from the plunger position and making the opening/closing operation of the automatic valve operated by the plunger more accurate.

In addition, when applying this automatic valve to a hot water mixing device, it is possible to accurately control the temperature and flow rate of discharged water, and furthermore, it is possible to accurately control the temperature and flow rate of the discharged water. By storing the relationship between the opening degree of the flow rate adjustment valve in a mathematical formula or table in advance, and immediately operating each valve based on the temperature and flow rate setting input,
Is the discharge water at the set temperature? The time required to reach the L amount can be significantly shortened, and if this is corrected by a learning program, it becomes possible to control the temperature and flow rate more quickly and accurately.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view of a hot water mixing device to which the piezoelectric actuator driving method according to the present invention is applied. FIG. 2 to FIG. 11 are explanatory diagrams showing the order of operation of the piezoelectric actuator. FIG. 5 is a cross-sectional explanatory diagram of an automatic faucet to which the hot water mixing device is applied. FIG. 6 is a front view of the operating section. FIG. 7 is a block diagram showing the configuration of the control device. fDI) (02): Piezoelectric actuator (C): Control device (P) Two-part plunger (e) (f) ((1) (h): Piezoelectric element (11): Valve body Patent applicant Toto Kiki Co., Ltd. Company Agent Ken Matsuo Part 5-OLO

Claims (1)

[Claims] 1) Plunger (P) and piezoelectric element for clamp (e)
(f) and piezoelectric elements (g) and (h) for stroke, the valve body (11) is operated by a piezoelectric actuator that moves the plunger (P) with a pulse-like control output from the control device (C). In an automatic valve designed to operate,
When a valve closing signal is input to the control device (C), the number of pulses exceeding the number of pulses to operate the valve body (11) from the position of the valve body (11) to the closing position at the time when the valve closing signal is input is An automatic valve characterized by being equipped with a control device that performs a control output in the closing direction.