Pressure Regulating Vacuum Valve

Abstract

To provide a pressure adjustment vacuum valve capable of reducing vibration due to driving of a valve body.SOLUTION: A pressure adjustment vacuum valve comprises: a valve body; a drive unit 71 that drives the valve body to open and close; a control unit 72 as an opening control unit that controls the opening degree of the valve body driven by the drive unit 71; and a control unit 72 as a setting unit that sets drive parameters of valve body drive from a first opening at which the drive starts to a second opening at which the drive stops so as to reduce valve body drive power.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a pressure regulating vacuum valve. [Background technology]

[0002] In semiconductor manufacturing equipment such as a film forming apparatus and an etching apparatus used in manufacturing semiconductors, flat panel displays, touch screen panels, etc., processes such as thin film processing and etching are performed while controlling the supply of gas and adjusting the pressure. In such semiconductor manufacturing equipment, a vacuum valve is disposed for adjusting the pressure of the vacuum chamber and isolating the space between the vacuum chamber and the vacuum pump. The vacuum valve used to adjust the pressure of the vacuum chamber is called a pressure adjusting vacuum valve or an automatic pressure control valve, and for example, a vacuum valve such as that described in Patent Document 1 is known. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-112260 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when the valve disc is accelerated or decelerated, particularly when the valve disc is stopped, vibration of the valve disc is likely to occur, and this vibration has a negative effect on pressure measurement values ​​and pressure control. [Means for solving the problem]

[0005] A pressure regulating vacuum valve according to an embodiment of the present invention comprises a valve body, a drive unit which drives the valve body to open and close, an opening control unit which controls the opening of the valve body driven by the drive unit, and a setting unit which sets drive parameters for driving the valve body from a first opening to a second opening so as to reduce the valve body drive power. Effect of the Invention

[0006] According to the present invention, it is possible to reduce vibrations caused by driving the valve body. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram showing a schematic configuration of a vacuum process device equipped with a pressure regulating vacuum valve. [Diagram 2] FIG. 2 is a plan view of the pressure regulating vacuum valve as viewed from the intake port side. [Diagram 3] FIG. 3 is a diagram showing two types of patterns regarding changes in the valve opening degree. [Figure 4] FIG. 4 is a diagram showing pressure response curves corresponding to the two types of patterns shown in FIG. [Diagram 5] FIG. 5 is a diagram showing the drive speed and torque current in slow-up / slow-down drive. [Figure 6] FIG. 6 is a diagram showing a drive pattern in the case where the drive time T′ is longer than the drive time T shown in FIG. [Figure 7] FIG. 7 is a flowchart showing an example of a drive pattern setting procedure. [Figure 8] FIG. 8 is a diagram showing an example of a conventional method for setting a drive pattern. [Figure 9] FIG. 9 is a diagram showing an example of a drive pattern setting method according to the present embodiment. [Figure 10] FIG. 10 is a diagram showing an example of the functions F(V) and G(V). [Figure 11] FIG. 11 is a diagram illustrating a trapezoidal pattern in the first modification. [Figure 12] FIG. 12 is a diagram illustrating a triangular pattern in the first modification. [Figure 13] FIG. 13 is a diagram illustrating the second modification. [Figure 14] FIG. 14 is a diagram showing an example of the calibration mode operation. [Figure 15]FIG. 15 is a block diagram of a pressure regulating vacuum valve and a valve controller in the second embodiment. [Figure 16] FIG. 16 is a diagram showing the drive speed, torque current, and drive power in slow-up / slow-down drive. [Figure 17] FIG. 17 is a flowchart showing an example of a drive parameter setting process in the second embodiment. [Figure 18] FIG. 18 is a diagram showing an example of a drive pattern setting based on the drive amount Δθa during pressure adjustment and the drive time Tu calculated as the upper limit of the drive time T. In FIG. [Figure 19] FIG. 19 is a diagram showing functions F1(V), G11(V), and G31(V) in the third modification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. -First embodiment- FIG. 1 is a block diagram showing a schematic configuration of a vacuum process apparatus 100 equipped with a pressure regulating vacuum valve 1 of the present invention. The vacuum process apparatus 100 is, for example, a CVD apparatus, and a turbo molecular pump 3 is connected to an apparatus chamber 2 via the pressure regulating vacuum valve 1. The vacuum pump used for evacuating the apparatus chamber 2 is not limited to the turbo molecular pump 3. An auxiliary pump 4 such as a rotary pump or a dry pump is connected to the exhaust side of the turbo molecular pump 3. The pressure regulating vacuum valve 1 is controlled by a valve controller 7. The turbo molecular pump 3 is controlled by a TMP controller 8. The apparatus chamber 2 is provided with a vacuum gauge 6 for measuring the pressure inside the chamber, and a mass flow controller (MFC) 5 for controlling the flow rate of gas introduced into the apparatus chamber 2. The MFC 5 is controlled by an apparatus controller 9 of the vacuum process apparatus 100. The pressure measurement value measured by the vacuum gauge 6 is input to the apparatus controller 9 and the valve controller 7.

[0009] The valve controller 7 includes a drive unit 71 that drives a motor for opening and closing the pressure regulating vacuum valve 1, and a control unit 72 that controls the aperture of the pressure regulating vacuum valve 1. The control unit 72 controls the aperture based on the target pressure input from the equipment controller 9 and the pressure measurement value input from the vacuum gauge 6, and adjusts the pressure in the equipment chamber 2 to the target pressure. The control unit 72 is a digital computing device, and is composed of, for example, a microcomputer or a field programmable gate array (FPGA) equipped with a central processing unit (CPU), a read-only memory (ROM) that stores control programs, etc., a random access memory (RAM), and an input / output interface (I / O interface).

[0010] The effective pumping speed of the exhaust system consisting of the pressure regulating vacuum valve 1 and the turbo molecular pump 3 is the composite pumping speed of the conductance of the pressure regulating vacuum valve 1 and the pumping speed of the turbo molecular pump 3. By changing the valve element opening, the conductance of the pressure regulating vacuum valve 1 changes, and the effective pumping speed of the exhaust system changes. The pressure of the equipment chamber 2 is adjusted by controlling the valve element opening relative to the flow rate of gas introduced into the equipment chamber 2.

[0011] Figure 2 is a plan view of the pressure regulating vacuum valve 1 as seen from the intake side. The valve plate 11, which is the valve body, is housed in the valve body 13 of the pressure regulating vacuum valve 1. An intake flange 132 having an opening 131 is provided on the intake side of the valve body 13. An exhaust flange (not shown), to which the turbo molecular pump 3 of Figure 1 is attached, is provided coaxially with the intake flange 132 on the exhaust side (the side opposite to the intake side) of the valve body 13.

[0012] The motor 12 that drives the valve plate 11 to open and close rotates in forward and reverse directions to drive the valve plate 11 to swing in a plane parallel to the intake port flange 132. The rotational position of the motor 12 is detected by an encoder 121 provided on the motor 12 and sent to the valve controller 7 of FIG. 1. As the valve plate 11 is driven to swing, the valve plate 11 slides horizontally to open and close the valve. The valve plate 11 is driven to open and close between a 0% opening position facing the entire opening 131 and a 100% opening position retracted from the opening 131.

[0013] Next, the control of the drive time of the valve plate 11 in the control unit 72 of the valve controller 7 will be described. As described above, the valve disc is likely to vibrate when it is driven, particularly when it is stopped, and the valve disc vibration adversely affects the pressure measurement value and the actual pressure value. The greater the acceleration when the valve disc is stopped, the greater the vibration when it is stopped. In order to reduce the acceleration, it is sufficient to increase the time required to drive the valve disc; the longer the drive time, the smaller the acceleration of the valve disc drive can be, and the smaller the vibration when it is stopped can also be.

[0014] However, if the drive time when changing the opening is long, it will affect the pressure response when the opening is changed. The pressure control of the device chamber 2 by the pressure regulating vacuum valve 1 is performed by controlling the opening of the valve plate 11 based on the pressure response information of the device chamber 2 to the opening change of the pressure regulating vacuum valve 1 and the pressure measurement value. Here, the pressure response information is information on the change in the pressure estimated value when it is assumed that the valve body opening is changed instantly. In reality, the opening change takes time, and the longer the drive time, the larger the deviation between the change in the pressure estimated value in the pressure response information and the actual pressure change (i.e., the change in the pressure measurement value) becomes, which results in an effect on the pressure control. Therefore, when the drive time is lengthened to suppress the valve body vibration, it is necessary to set the length of the drive time so that the effect on the pressure response, i.e., the effect on the pressure control, due to the longer drive time is within an acceptable range.

[0015] Figures 3 and 4 are diagrams explaining the pressure response when the valve disc opening θ is changed from θ1 to θ2 (<θ1). Figure 3 shows two patterns for changing the valve disc opening θ. Pattern a is the case where it is assumed that the valve disc opening θ changes instantly from θ1 to θ2 at t=0. Pattern c is the case where it is assumed that the valve disc opening θ changes instantly from θ1 to θ2 at t=T. Figure 4 shows the pressure response curves La and Lc when the valve disc opening θ is changed in patterns a and c, respectively. La is the pressure characteristic when it is assumed that T=0, and Lc represents the actual pressure characteristic.

[0016] The pressure response can be estimated based on the exhaust equation shown in Equation (1) below. P=Qin / Se(θ)-(V / Se(θ))×(dP / dt) …(1) In equation (1), V is the volume of the equipment chamber 2 (hereinafter referred to as chamber volume V), Se(θ) is the effective pumping speed of the exhaust system for the equipment chamber 2, and Qin is the flow rate of gas introduced into the equipment chamber 2.

[0017] By solving equation (1) with the value of P at t = 0 as Pini (initial pressure value: pressure before the opening is changed), we obtain the following equation (2) which represents the pressure response curve. P(t)=Po·(1-exp(-t / τ))+Pini·exp(-t / τ) …(2) In equation (2), τ is the time constant of the pressure response curve, and is given by τ = V / Se(θ). Additionally, Po is the pressure when the valve disc opening has converged to a steady state, and is given by Po = Qin / Se(θ). The pressure response curve La(t) in FIG. 4 is the pressure response curve when the valve disc opening is θ2, and is therefore expressed by equation (3) where the time constant τ in equation (2) is τa = V / Se(θ2). Additionally, the pressure response curve Lc(t) is obtained by translating the pressure response curve La(t) by +T on the time axis, and is expressed by the following equation (4) which has the same time constant τa as the pressure response curve La(t). La(t)=Po(1-exp(-t / τa))+Pini·exp(-t / τa) …(3) Lc(t)=Po(1-exp(-(tT) / τa))+Pini·exp(-(tT) / τa)…(4)

[0018] (How to set the drive time T) As described above, the drive time T must be set so that the effect on pressure response, i.e., the effect on pressure control, is within an acceptable range. Various indices can be considered as indices showing the effect of the drive time T on pressure response, but here we focus on the pressure difference ΔPτ at t=τa between the two pressure response curves La, Lc shown in Figure 4. In Figure 4, La(τa) is expressed by the following equation (5), and ΔPτ is expressed by the following equation (6). If the ratio ΔPτ / La(τa) is called the pressure error, the pressure error can be expressed as in the following equation (7). La(τa)=0.63Po+0.37Pini …(5) ΔPτ=La(τa)-Lc(τa) …(6) Pressure error = [La(τa)-Lc(τa)] / La(τa) …(7)

[0019] Here, consider the case where T is sufficiently smaller than τa. For example, let T = τa / 10. By substituting t = τa and T = τa / 10 into equations (3) and (4), La(τa) and Lc(τa) are calculated by the following equations (8) and (9). La(τa)=Po(1-exp(-1))+Pini·exp(-1) ≒0.63Po+0.37Pini …(8) Lc(τa)=Po(1-exp(-(τa-T / 10) / τa))+Pini·exp(-(τa-T / 10) / τa) =Po(1-exp(-0.9))+Pini·exp(-0.9) ≒0.59Po+0.41Pini …(9) By substituting equations (8) and (9) into equation (7) and assuming Po>>Pini, Pini can be ignored, and the pressure error is approximately 6%, as shown in the following equation (10). Pressure error = (0.63Po-0.59Po) / 0.63Po ≒ 0.06 … (10) When the chamber size is large, τa becomes large, so T, which results in the same level of pressure error, can also be increased.

[0020] The pressure error in equation (7) is due to the drive time T, and it is sufficient if it is small enough that its effect on the pressure response can be ignored. The upper limit of such a pressure error is not uniformly determined, but depends on, for example, the pressure control accuracy required in the process performed in the vacuum chamber. Here, the error in pressure required from the viewpoint of such pressure control accuracy is called the required error ΔE. The drive time corresponding to this required error ΔE is set as the drive time Tu, which is the upper limit of the drive time T.

[0021] Generally, a stepping motor is used for the motor 12 that drives the valve plate 11 to open and close, and a slow-up / slow-down drive is usually performed as shown in Figure 5. Figure 5 shows the drive speed and torque current in the slow-up / slow-down drive. In general, the torque generated by the motor is proportional to the drive current I. In the slow-up / slow-down drive, the drive time T is represented by a slow-up section S1 where the speed increases, a constant speed section S2 where the speed is constant at the upper limit speed vmax, and a slow-down section S3 where the speed decreases. The area of ​​the trapezoid shown in Figure 5 is the time integral of the speed, and therefore represents the amount of change in the opening during the drive time T (hereinafter referred to as the drive amount). The speed in the constant speed section is set to the fastest during the drive period, and the speed in the constant speed section is the upper limit speed during the drive period. Therefore, the speed in the constant speed section is represented as the upper limit speed vmax. In general, in order to control pressure at high speed, the speed in the constant speed section is often set to the upper limit speed Vmax of the valve body drive capacity.

[0022] In the constant speed section S2, a load torque (torque current I2) is required to compensate for losses including friction in order to drive the valve plate 11 while maintaining a constant speed vmax. In the slow-up section S1, an acceleration torque is required in addition to the load torque, so the torque current I1 is larger than I2. Conversely, the torque required in the slow-down section S3 is the load torque (torque current I2) minus the acceleration torque (torque current I1-I2). Since the load torque is usually smaller than the acceleration torque, the torque current I3 in the slow-down section S3 is a negative value. In other words, it is regenerated to the power supply. Note that, for simplicity's sake, the absolute value of the slope (absolute value of acceleration) in the slow-up section S1 and the slow-down section S3 are set to be the same, so S1=S3.

[0023] FIG. 6 is a diagram showing a drive pattern in which the drive amount is the same, but the drive time T' is longer than the drive time T shown in FIG. 5. In the case of FIG. 6, S21 is also set to S23, and vmax2<vmax、S21> The settings are such that S1, S22>S2, S23>S3. Since the drive amount is the same in the cases of Fig. 5 and Fig. 6, the trapezoid area in Fig. 5 is equal to the trapezoid area in Fig. 6. Since the load torque in the constant speed sections S2, S22 is almost the same, the torque current I2, I22 is I2=I22.

[0024] On the one hand, since the absolute value of the slope (absolute value of acceleration) in the ramp-up section S21 and the ramp-down section S23 in FIG. 6 is smaller than that in the ramp-up section S1 and the ramp-down section S3 in FIG. 5, the torque current value corresponding to the accelerating torque is smaller in any section. Therefore, I21 < I2, (absolute value of I23) < (absolute value of I3). Thus, by setting T’ > T, the absolute value of the slope (absolute value of acceleration) in the ramp-up section S21 and the ramp-down section S23 becomes smaller, and the vibration of the valve plate 11 during valve body drive (especially during stop) can be suppressed more, and the adverse effect on pressure control can be prevented. Also, by setting the drive time T’ longer within the range of the upper limit value Tu as in the case of FIG. 6, compared with the case of FIG. 5 where the drive time T is short, the capacity of the DC power supply to be prepared can be reduced, and the output power during ramp-up can also be suppressed.

[0025] (Method for setting drive pattern) As described above, if the drive time T is determined, the drive pattern of the ramp-up / ramp-down drive is set according to the drive time T. FIG. 7 is a flowchart showing an example of the drive pattern setting procedure. The program for setting the drive pattern shown in FIG. 7 is executed by the control unit 72 of the valve controller 7. Note that a standard drive pattern is stored as a reference drive pattern in the memory of the control unit 72.

[0026] The flow chart of FIG. 7 starts when the valve element opening θ2 (see FIG. 3) after the opening change is input from the equipment controller 9. The required error ΔE, which is the pressure error required for the process, is input in advance from the equipment controller 9. In step S10, the effective pumping speed Se(θ2) is calculated based on the valve element opening θ2 input from the equipment controller 9 and the opening-effective pumping speed correlation Se(θ) stored in the memory of the control unit 72. In step S20, the time constant τ=V / Se(θ2) is calculated from the effective pumping speed Se(θ2) and the chamber volume V stored in the memory of the control unit 72. In step S30, the upper limit Tu of the drive time T is set based on the valve element opening θ2 input from the equipment controller 9 and the pressure measurement value Pini measured by the vacuum gauge 6. In step S40, a drive pattern corresponding to the drive time Tu is set as described below based on the reference drive pattern stored in the memory of the control unit 72 and the upper limit Tu calculated in step S30.

[0027] FIG. 8 is a diagram showing an example of a conventional drive pattern setting method. The drive pattern on the left side of the figure shows a reference drive pattern, and the area of ​​the trapezoidal shape is set to a reference drive amount Δθ. In FIG. 8, S1=S3 is shown. The drive pattern on the right side of the figure is a drive pattern for a drive amount Δθa (>Δθ), and is set based on the reference drive pattern. In the conventional drive pattern setting method shown in FIG. 8, the drive pattern for the drive amount Δθa has a speed in the constant speed section set to the same as the speed vmax of the reference pattern, and the lengths of the slow-up section S2 and the slow-down section S3 are also set to the same as the reference pattern.

[0028] That is, in the conventional drive pattern setting method shown in Fig. 8, regardless of the magnitude of the drive amount Δθa, slow-up drive and slow-down drive are performed with the same acceleration, and constant-speed drive is performed with the same speed vmax. Therefore, although the length of the constant-speed section S2 changes according to the magnitude of the drive amount Δθa, the lengths of the slow-up section S2 and the slow-down section S3 are the same for both drive patterns, so the influence of vibration when driving stops does not change. Although Fig. 8 shows the case where Δθa>Δθ, the same applies when Δθa<Δθ.

[0029] Fig. 9 is a diagram showing an example of a drive pattern setting method in this embodiment. The drive pattern on the left side of the figure is a conventional case, and the drive time Ta is set for the drive amount Δθa in the procedure described in Fig. 8. The drive pattern shown on the right side of the figure is a drive pattern in this embodiment, and the drive amount is the same Δθa as the conventional drive pattern on the left side of the figure. Here, the drive pattern of the embodiment is set to have the ratios S1b / S2b and S3b / S2b set to the same values ​​as the corresponding ratios S1 / S2a and S3 / S2a of the conventional drive pattern.

[0030] As described above, in the conventional drive pattern setting method, the speed of the constant speed section is set to the upper limit speed Vmax of the valve body drive capacity, so the drive time Ta is set as short as possible. On the other hand, the drive time Tu is the drive time when the pressure error is equal to its upper limit value (=required error ΔE), and is a larger value than the drive time Ta in the conventional case. The drive amount Δθa is the same as that of the drive pattern on the left side of the figure, but the drive time Tu is Tu>Ta, so the speed vmaxb of the constant speed section is smaller than the speed vmax of the constant speed section in the reference drive pattern. In addition, the lengths of the slow-up section S1b, the constant speed section S2b, and the slow-down section S3b are longer than the lengths of the corresponding slow-up section S1, the constant speed section S2a, and the slow-down section S3 in the conventional drive pattern. As a result, the absolute values ​​of the acceleration (slope of the oblique side) of the slow-up section S1b and the slow-down section S3b are smaller than the absolute values ​​of the acceleration of the slow-up section S1 and the slow-down section S3 in the conventional drive pattern, and vibration can be reduced.

[0031] (Speed ​​and acceleration in constant speed sections) When a drive time Tu (>Ta) is given, the speed (upper limit speed vmax) and acceleration of the constant speed section are set according to the drive pattern. The upper limit speed vmaxb of the drive pattern of the embodiment shown on the right side of Fig. 9, the absolute value α1 of the acceleration of the slow-up section S1b, and the absolute value α3 of the acceleration of the slow-down section S3b are calculated as follows. Here, the ratios shown in Fig. 9 are expressed as S1 / S2a=S1b / S2b=A1, S3 / S2a=S3b / S2b=A3 using constants A1 and A3.

[0032] Since the sum of each of the sections S1b, S2b, and S3b is Tu, (A1+1+A3)S2b=Tu holds, and S1b, S2b, and S3b are expressed by the following equations (16) to (18). S1b = B1 · Tu …(16) S2b = B2 · Tu …(17) S3b = B3 · Tu …(18) Where B1=A1 / (A1+1+A3), B2= 1 / (A1+1+A3), and B3=A3 / (A1+1+A3).

[0033] Since the area of ​​the trapezoid in the drive pattern of the embodiment in FIG. 9 is equal to the drive amount Δθa, the relationship of the following equation (19) holds between the upper limit speed vmaxb and the drive amount Δθa. vmaxb·(S1b / 2+S2b+S3b / 2)=Δθa …(19) Equation (19) is rearranged using equations (16) to (18) to obtain equation (20), and the maximum velocity vmaxb is calculated using equation (21). vmaxb·Tu(B1+2·B2+B3)=2Δθa …(20) vmaxb=2D(Δθa / Tu) …(21) where D = (A1+1+A3) / (A1+2+A3).

[0034] The absolute value α1 of the acceleration in the slow-up section S1b and the absolute value α3 of the acceleration in the slow-down section S3b are expressed as follows: α1=vmaxb / S1b=vmaxb / (B1·Tu) =(1 / B1)·(vmaxb / Tu) =(1 / B1)·(2D(Δθa / Tu) / Tu) =(2D / B1)·(Δθa / Tu 2 ) …(twenty two) α3=vmaxb / S3b=vmaxb / (B3·Tu) =(1 / B3)·(vmaxb / Tu) =(2D / B3)·(Δθa / Tu 2 ) …(twenty three)

[0035] Here, when the value of the drive time Tu is set to 0.1τa, a value at which the pressure error can be ignored, the upper limit speed vmaxb and absolute values ​​of acceleration α1, α3 are calculated as follows. The time constant τa is the time constant of the pressure response curve La shown in Fig. 4, and is expressed as τa = V / Se(θ2) using the chamber volume V and the effective exhaust speed Se(θ2). Substituting Tu = 0.1τa = 0.1(V / Se(θ2)) into equations (21) to (23), equations (24) to (26) are obtained, respectively. vmaxb=20D{Δθa / (V / Se(θ2))} …(24) α1=100(2D / B1)·{Δθa / (V / Se(θ2)) 2} …(twenty five) α3=100(2D / B3)·{Δθa / (V / Se(θ2)) 2} …(26)

[0036] As shown in formulas (24) to (26), the values ​​vmaxb, α1, and α3 depend on the chamber volume V and the effective pumping speed Se(θ2). Therefore, when the valve opening θ2 for each control is different, optimization can be achieved by variably setting the values ​​vmaxb, α1, and α3 for each control. Also, since varying the above values ​​for each control is complicated, they may be functions of only the chamber volume V, which is usually a fixed value. In this case, a representative value is used for the changing effective pumping speed Se(θ2). For example, when the effective pumping speed changes from 1500L / s to 15L / s with the change in the opening, the geometric mean √(15×1500)=150L / s is used as the representative value. In this case, the values ​​vmaxb, α1, and α3 are functions of the chamber volume V as shown in the following formulas (27) to (29). vmaxb=F(V)=3000D(Δθa / V) …(27) α1=G1(V)=200·150 2 (D / B1)·{Δθa / V 2} …(28) α3=G3(V)=200·150 2 (D / B3)·{Δθa / V 2} …(29) In addition, the driving amount Δθb is set to a fixed value of about 70 deg in the case of a slide type pressure regulating vacuum valve.

[0037] As shown in the following equations (27) to (29), the function F(V) is proportional to 1 / V, and the function G(V) is proportional to 1 / V. 2 Since the functions F(V) and G(V) are proportional to the chamber volume V, the functions F(V) and G(V) change as shown in FIG. 10 with respect to the chamber volume V. As the chamber volume V decreases, the values ​​vmaxb, α1, and α3 increase, but since there is an upper limit to the valve body driving ability of the valve controller 7, when the chamber volume V decreases and the values ​​of F(V) and G(V) reach their respective upper limits, the functions F(V) and G(V) become constant. Instead of the functions F(V) and G(V) expressed by the formulas (27) to (29), a straight line sloping downward to the right with respect to the increase in the chamber volume V as shown by the dashed line, or a function that monotonically decreases with the increase in the chamber volume V may be used. Although not shown, a function that decreases in a stepwise manner may also be used.

[0038] (Modification Example 1) In the example shown in FIG. 9, the drive pattern was set so that the ratios S1b / S2b and S3b / S2b of the drive patterns in the embodiment are the same as the ratios S1 / S2a and S3 / S2a in the conventional case. In Modification Example 1, for the calculated Tu, first, the upper limit speed vmaxb is determined. When setting the upper limit speed vmaxb for the given drive amount Δθa and drive time Tu, if it is set to satisfy Δθa>Tu×vmaxb / 2, the shape of the drive pattern becomes a trapezoid as shown in FIG. 11. Also, if it is set such that Δθa = Tu×vmaxb / 2, the shape of the drive pattern becomes a triangle as shown in FIG. 12. However, it is not possible to set the upper limit speed vmaxb such that Δθa<Tu×vmaxb / 2. That is, the upper limit speed vmaxb is set such that vmaxb≦2Δθa / Tu.

[0039] In pattern A of FIG. 11, it is set such that S1b = S3b, and the shape of the drive pattern is an isosceles trapezoid. The drive amount Δθa is represented by the sum “Δθ1 + Δθ2 + Δθ3” of the drive amount Δθ1 in section S1b, the drive amount Δθ2 in section S2b, and the drive amount Δθ3 in section S3b. On the other hand, the lower pattern B in the figure shows the case when it is set such that S1b’≠S3b’. Since pattern B is set such that S3b<S3b’, the magnitude of the acceleration in the deceleration section is smaller than that of pattern A, and the vibration at the time of valve body stop can be made smaller.

[0040] Since the drive amounts Δθa of patterns A and B are equal, Δθ1 + Δθ3 = Δθ1’ + Δθ3’ holds. That is, in the case of the trapezoid pattern shown in FIG. 11, when the upper limit speed vmaxb is set such that Δθa>Tu×vmaxb / 2 from the drive amount Δθa and the drive time Tu, the value of Δθ1 + Δθ3 is determined. Next, under the condition of “Δθ1 + Δθ3 = constant”, the drive amounts Δθ1 and Δθ3 in sections S1b and S3b, that is, the lengths of sections S1b and S3b, are determined to desired values.

[0041] FIG. 12 is a diagram showing a case where the shape of the drive pattern is a triangle. Pattern C is a case where S1b=S3b is set, and pattern D is a case where S1b'≠S3b' is set. Naturally, the value of the upper limit speed vmaxb in FIG. 12 is greater than the value of the upper limit speed vmaxb in FIG. 11. In the case of the triangular pattern shown in FIG. 12, the upper limit speed vmaxb is also set so as to satisfy Δθa=Tu×vmaxb / 2 from the drive amount Δθa and drive time Tu. In this case, Δθa=Δθ1+Δθ3. Then, the drive amounts Δθ1 and Δθ3 of the sections S1b and S3b, i.e., the lengths of the sections S1b and S3b, are determined to be desired values.

[0042] In both the trapezoidal pattern of FIG. 11 and the triangular pattern of FIG. 12, the value of the sum "S1b+S3b" is determined from the drive amount Δθa, drive time Tu, and upper limit speed vmaxb. In this case, by setting the value of the sum "S1b+S3b" to a larger value, it is possible to reduce vibration when the valve disc drive is stopped. The value of the sum "S1b+S3b" becomes the largest when the drive pattern is shaped like a triangle as shown in FIG. 12. In this case, the upper limit speed vmaxb is given by vmaxb=2Δθa / Tu.

[0043] (Variation 2) Fig. 13 is a diagram illustrating Modification 2. In the case of a valve with high valve disc drive capacity, it is preferable to set the upper limit speed vmaxb to the highest possible value and change only the absolute values ​​of acceleration α1, α3 as a function of V. In this case, S1c / S2c ≠ S1 / S2a, S3c / S2c ≠ S3 / S2b, and the absolute values ​​of acceleration α1, α3 are smaller than in the drive pattern of the embodiment on the left side of the figure. In Fig. 13, the upper limit speed vmaxb is set to the drive capacity upper limit of the valve controller 7.

[0044] (Calibration mode) When pressure control is performed by the pressure regulating vacuum valve 1, the control is performed based on the chamber volume V of the equipment chamber 2 and the effective pumping speed Se(θ) of the exhaust system (pressure regulating vacuum valve 1, turbo molecular pump 3). Therefore, it is common to measure the chamber volume V of the equipment chamber 2 and the effective pumping speed Se(θ) of the exhaust system before attaching the exhaust system to the equipment chamber 2 and performing the process. The time constant τ, which expresses the characteristics of the above-mentioned pressure response curve, is also expressed as the ratio of the chamber volume V to the effective pumping speed Se(θ), such as τ=V / Se(θ), so it is important to accurately grasp the chamber volume V and the effective pumping speed Se(θ) in order to improve the control accuracy of pressure control and to appropriately set the drive time T.

[0045] 14 is a diagram showing an example of the calibration mode operation, which shows the opening θ (solid line L31) of the pressure regulating vacuum valve 1 and the pressure P (dashed line L32) of the device chamber 2 measured by the vacuum gauge 6. In the calibration mode operation shown in FIG 14, first, the effective pumping speed S(θ) at multiple openings θ(i) is measured, and then the chamber volume V is measured.

[0046] To measure the effective pumping speed S(θ), the pressure P (which can be considered as approximately the equilibrium pressure) is measured at multiple openings θ(i) for the gas flow rate Qin, and the effective pumping speed S(θ) is calculated using the formula "S(θ) = Qin / P." To measure the chamber volume V, the pressure control vacuum valve 1 is fully closed (effective pumping speed = 0) with the gas flow rate Qin, and the pressure change rate dP / dt is measured. The chamber volume V is calculated using the formula "V = Qin / (dP / dt)."

[0047] First, the opening θ is set to 100%, a gas of a predetermined flow rate Qin is introduced into the device chamber 2, and the pressure value is waited until it stabilizes. Next, a process of acquiring pressure at a plurality of openings θ(i) is performed, where i=1, 2, 3, . . . , N. At time t1, the opening θ is changed from 100% to θ(1)=0%, and when the pressure stabilizes, the pressure value P(1) is measured by the vacuum gauge 6. Note that opening=0% is a state in which the valve plate 11 is disposed in a position facing the opening 131 as shown in FIG. 2, and is not a state in which the valve plate 11 is pressed against the valve seat (fully closed state). Therefore, although the pressure value rises due to the opening change, when the pressure rise becomes zero and the pressure value stabilizes, the pressure value corresponds to the valve conductance at opening=0%.

[0048] Similarly, at times t2, t3, . . . , tN, the opening is set to θ(2), θ(3), . . . , θ(N) = 100%, and pressure values ​​P(2), P(3), . . . , P(N) for multiple openings θ(2), θ(3), . . . , θ(N) = 100% are obtained. Then, effective exhaust speeds S(θ1) to S(θN) are calculated from the obtained pressure values ​​P(1) to P(N) and the flow rate Qin.

[0049] Next, at time ta, the opening θ is changed from 100% to the fully closed state, and multiple pressure values ​​are measured at multiple different times during the pressure increase process. Then, the pressure change rate dP / dt is calculated based on the multiple pressure values, and the chamber volume V is calculated from V=Qin / (dP / dt). The calculated chamber volume V and effective exhaust speeds S(θ1)-S(θN) are stored in a memory provided in the control unit 72 of the valve controller 7.

[0050] By executing the above-mentioned calibration mode, it is possible to obtain more accurate values ​​for the chamber volume V and the effective pumping speed S(θ) in a state where the exhaust system is connected to the equipment chamber 2. As a result, it is possible to set a more appropriate driving time while ensuring the accuracy of the pressure control. Here, the chamber volume V and the effective pumping speed S(θ) in a state where the exhaust system is connected to the equipment chamber 2 are obtained by the calibration mode operation and stored in the memory of the control unit. However, the user may store in the memory of the control unit 72 the volume of the equipment chamber 2 calculated from the design drawing, the conductance data of the pressure control valve 1, and the calculated effective pumping speed of the exhaust system calculated from the data on the exhaust performance of the turbo molecular pump.

[0051] -Second embodiment- In the first embodiment described above, for example, as in the case of Fig. 6, the drive time T', which is a drive parameter, is set long within the range of the upper limit Tu, and the absolute value of the gradient (absolute value of acceleration) in the slow-up section S21 and the slow-down section S23 is reduced, thereby reducing vibration when the valve body is driven. As can be seen from Fig. 5, the magnitude of the absolute value of acceleration represents the magnitude of the torque current (i.e., power), and vibration is reduced by making the power smaller in the slow-up section S21 and the slow-down section S23.

[0052] Incidentally, in a pressure regulating vacuum valve, for example, the specifications prescribe a minimum power supply capacity that allows such drive operation for a valve disc operating speed (or acceleration) set as shown in FIG. 5. The user is required to prepare a power supply having a power supply capacity equal to or greater than the minimum power supply capacity. For this reason, if a power supply having a power supply capacity smaller than the minimum power supply capacity is used, for example, motor control in a slow-up section where the power is large may not be performed correctly, and accurate pressure regulation control may not be possible. In the second embodiment, a valve control that can prevent such inconvenience from occurring, i.e., a function of changing the valve disc drive parameter settings according to the capacity of the power supply, will be described.

[0053] 15 is a block diagram of the pressure regulating vacuum valve 1 and the valve controller 7. As described above, the pressure regulating vacuum valve 1 is provided with the motor 12 for driving the valve plate 11 (see FIG. 2) to open and close, and the encoder 121 for detecting the rotational position of the motor 12. The position of the valve plate 11 can be obtained from the amount of rotation of the motor 12.

[0054] The valve controller 7 is connected to the external DC power source 10 and the device controller 9 via an external interface 73. The target pressure from the device controller 9 is input to the control unit 72 via a communication unit 74. The drive unit 71 drives the motor 12 based on a control signal from the control unit 72. The pressure regulating vacuum valve 1 is supplied with power from the external DC power source 10, and the power supply unit 75 supplies power of a voltage corresponding to each unit, such as the drive unit 71 and the control unit 72. Usually, PWM control is used for driving the motor. At this time, the drive voltage becomes the voltage of the external DC power source 10, and the drive current becomes a torque current smoothed by PWM control. As described later, the control unit 72 monitors the power supply voltage signal and the torque current signal, compares them with a threshold value, and issues an alarm. The user can perform the settings described later by manually operating the operation unit 76 provided in the valve controller 7. The display unit 77 displays the state, settings, alarms, etc. of the pressure regulating vacuum valve 1.

[0055] Generally, a DC power supply has an overload (overcurrent) protection function that reduces the output voltage when it detects an overload, and shuts down the output when it detects that the overload is at an output short circuit level. The output voltage drop of the external DC power supply 10 is detected by the power supply unit 75, and the detection result is input to the control unit 72. In this embodiment, an overload (overcurrent) is judged by monitoring the voltage drop of the external DC power supply 10, and driving parameters, which will be described later, are determined based on the judgment result.

[0056] FIG. 16 is FIG. 5 with the addition of a graph of changes in drive power. In general, the torque current that contributes to generating the torque generated by a motor is proportional to the drive current Idc supplied from the power supply. If the power supply voltage, which becomes the drive voltage, is Vdc, then the product of the drive voltage Vdc and the drive current Idc (Vdc × Idc) is the drive power P. If the power supply capacity is Pps and the maximum power required by control systems other than the drive power is Pα, then the maximum value of the drive power Pmax is expressed by the following equation (30). Pmax = Pps - Pα … (30)

[0057] 16, the power used to drive the valve disc, i.e., the maximum value of the power that the external DC power source 10 can provide, is Pmax, and at this time, the maximum value of the torque current, i.e., the motor current, is Imax. Drive parameters for driving the valve disc include drive time, drive acceleration, and drive speed, and in this embodiment, the valve disc drive is controlled so that the motor current during drive does not exceed the maximum value Imax, i.e., at a maximum speed vmax and a magnitude (absolute value) of acceleration αmax that are limited to Imax.

[0058] Setting of the driving parameters according to the capacity of the power supply is performed when the pressure regulating vacuum valve 1 is mounted in a chamber and used, or at the initial stage of the calibration mode described in the first embodiment. The driving parameters include the driving speed vmax in the constant speed section S2 in FIG. 16, and the magnitudes of acceleration α1, α3 in the slow-up section S1 and the slow-down section S3. Here, αmax=α1=α3, and vmax and αmax are the driving parameters. vmax and αmax are the maximum speed and the magnitude of acceleration corresponding to the above-mentioned Imax (Pmax). The setting step number n of the driving parameters (vmax, αmax) will be described taking the case of n=5 as an example. That is, as for the driving parameters, a set of driving parameters (vmax1, αmax1), (vmax2, αmax2), (vmax3, αmax3), (vmax4, αmax4), and (vmax5, αmax5) corresponding to five maximum powers Pmax1 to Pmax5 are preset in the memory of the control unit 72. Note that, when Pmax1 is set to αmax2, the maximum power Pmax2 is set to αmax3, and the maximum power Pmax3 is set to αmax4. <Pmax2<Pmax3<Pmax4<Pmax5であるとする。

[0059] Fig. 17 is a flowchart showing an example of a drive parameter setting process executed by the control unit 72. In step S110, the number of stages n of the preset drive parameters is set to 5. In step S120, the drive parameters are set to drive parameters (vmax5, αmax5) corresponding to the largest maximum power Pmax5. In step S130, the valve body is driven with the drive parameters (vmax5, αmax5). For example, slow-up drive as shown in Fig. 16 is performed with αmax5. At this time, a drive current Imax5 flows, and if this is an overload (overcurrent) for the external DC power supply 10, the output voltage of the external DC power supply 10 drops.

[0060] In step S140, it is determined whether the output voltage of the external DC power supply 10 has dropped, and if there has been a voltage drop, the process proceeds to step S150, and if there has been no voltage drop, the process proceeds to step S145. If the output voltage of the external DC power supply 10 has not dropped, the external DC power supply 10 can output the maximum power Pmax5, and therefore in step S145, the drive parameters (vmaxn, αmaxn) for the current stage number n=5 are determined as the drive parameters. On the other hand, if it is determined in step S140 that there has been a voltage drop, the process proceeds to step S150.

[0061] In step S150, it is determined whether the current drive parameter settings are (vmax1, αmax1). If it is determined that the current drive parameter settings are (vmax1, αmax1) (yes), the external DC power supply 10 cannot be used even with drive parameters for the smallest power Pmax1, so the process proceeds from step S150 to step S155 to issue an alarm. For example, the display unit 76 may display that the external DC power supply 10 has insufficient capacity, or an alarm signal notifying the external DC power supply 10 of insufficient capacity may be output to the equipment controller 9. On the other hand, if it is determined in step S150 that the current drive parameter settings are not (vmax1, αmax1), the process proceeds to step S160 to decrease the number of drive parameter steps n by 1, and the process returns to step S120.

[0062] As described above, the processes from step S120 to step S160 are repeatedly executed until it is determined in step S140 that there is no voltage drop, and the drive parameters (vmaxn, αmaxn) of the nth stage when it is determined in step S140 that there is a voltage drop are determined to be the drive parameters to be actually used. Then, if it is determined in step S140 that there is a voltage drop even with the drive parameter setting (vmax1, αmax1) of the smallest maximum power Pmax1, an alarm is issued in step S155 to notify the user of insufficient capacity of the external DC power supply 10.

[0063] (Setting the drive pattern during pressure regulation control) Fig. 18 is a diagram showing an example of a drive pattern setting based on the drive amount Δθa during pressure adjustment and the drive time Tu calculated as the upper limit of the drive time T. The drive pattern shown on the left side of Fig. 18 is a drive pattern set based on the drive parameters (vmaxn, αmaxn) and the drive time Tu. Once the drive parameters (vmaxn, αmaxn) are determined, the magnitude of acceleration in the slow-up section S1 and the slow-down section S3 are set as shown in the following formula (31), and the times of these sections are also automatically determined, so that the time S2a of the constant speed section is calculated by the following formula (32). The drive amount Δθ in this drive pattern is generally different from the drive amount Δθa. α1 = α2 = αmaxn …(31) S2a=Tu-(S1+S3) …(32)

[0064] Figure 18 shows the case where Δθ > Δθa. In this case, like the drive pattern shown on the right side of the figure, with the driving amount being Δθa, while the times S1, S2a, and S3 remain fixed, the speed in the constant-speed section, and the magnitudes of the acceleration in the speed-up section and the speed-down section are corrected to vmaxnb, α11, and α31, and the corrected values are adopted as the drive parameters. vmaxnb < vmaxn, and α11 = α31 < αmaxn. Note that in the case where Δθ < Δθa, α1 = α2 = αmaxn is set, and S2a is increased to be greater than the value calculated by Equation (32) so that Δθ = Δθa. Also, when Δθ = Δθa, the drive parameters (vmaxn, αmaxn) are used for control.

[0065] (Modification Example 3) In the first embodiment, the case of setting vmaxb and α1 as in Equations (27) and (28) using the functions F(V) and G1(V) of the chamber volume V as shown in FIG. 10 was described. vmaxb = F(V) = 3000D(Δθa / V) …(27) α1 = G1(V) = 200·150 2 (D / B1)·{Δθa / V 2} …(28) In the second embodiment, since the drive parameters (vmaxn, αmaxn) are determined by the process shown in FIG. 17, instead of the functions F(V), G1(V), and G3(V) in FIG. 10, F1(V), G11(V), and G31(V) as shown in FIG. 19 are adopted. F1(V), G11(V), and G31(V) are limited to the values vmaxn and αmaxn in a region where the chamber volume V is small.

[0066] (Modification Example 4) In the above-described second embodiment, in the calibration mode, the drive parameters are set to values ​​corresponding to the power supply capacity. However, a temporary load increase may occur in driving the valve body due to the adhesion of foreign matter inside the valve. Since the control unit 72 monitors the power supply voltage drop in real time, the setting change of the drive parameters can be applied to such a temporary load increase. In other words, if a power supply voltage drop is detected during the driving of the valve body, the drive parameters are lowered by one level. This makes it possible to prevent the overload (overcurrent) protection function of the external DC power supply 10 from being activated due to a temporary load increase in the driving of the valve body.

[0067] (Variation 5) In the second embodiment and the fourth modification, the control unit 72 is configured to automatically set the driving parameters, but the driving parameters may be input from outside and set. For example, a configuration may be added in which the user can operate the operation unit 76 to set the driving parameters. By operating the operation unit 76, a driving parameter setting screen is displayed on the display unit 77, and the desired driving parameters are selected from a plurality of settings. For example, a standard mode and one or more modes with a lower maximum power than the standard mode may be prepared, and the user may select one of them. The standard mode is set to a mode that uses the driving parameters determined in the calibration mode. Also, instead of the user operating the operation unit 76, the mode to be set may be set by a command from the device controller 9.

[0068] It will be understood by those skilled in the art that the exemplary embodiments and modifications described above are specific examples of the following aspects.

[0069] [1] A pressure regulating vacuum valve according to one embodiment includes a valve body, a drive unit which drives the valve body to open and close, an opening control unit which controls the opening of the valve body driven by the drive unit, and a setting unit which sets drive parameters for driving the valve body from a first opening to a second opening so as to reduce the valve body drive power. By setting the drive parameters for the valve disc drive so as to reduce the valve disc drive power, it is possible to reduce vibrations that accompany the valve disc drive from the start to the stop of drive.

[0070] [2] In the pressure regulating vacuum valve described in [1] above, the drive parameter is a valve element drive time, and the setting unit sets the valve element drive time based on an index indicating an effect on pressure response. For example, in the first embodiment described above, the valve body drive power is reduced by applying the pressure error estimate during pressure control caused by the drive time as an index showing the effect on pressure response, thereby making it possible to reduce the vibration of the valve body drive.

[0071] [3] In the pressure regulating vacuum valve described in [2] above, an estimated pressure error during pressure control caused by the drive time is applied as an index showing the effect on the pressure response, and the opening control unit sets the valve body drive time so that the estimated pressure error is equal to or less than a predetermined allowable value. For example, the above-mentioned pressure error "ΔPτ / La(τa)" is applied to the estimated pressure error, and the valve body drive time is set to Tu so that the pressure error "ΔPτ / La(τa)" is equal to or less than a predetermined allowable value (=required error ΔE).

[0072] As shown in Figures 3 and 4, if the drive time T is T=0, the pressure response curve has a time constant τ=V / Se(θ) as shown in curve La, so there is no effect on the pressure response. However, if T>0, the effect of the drive time T on the pressure response occurs as shown in pressure response curve Lb. For example, when driving with the drive pattern shown on the right side of Figure 9, the longer the drive time T, the better in order to reduce vibration when the valve disc is driven, but conversely, the longer the drive time T, the greater the effect on the pressure response. Therefore, by setting the drive time Tu so that the pressure error ΔPτ / La(τa) satisfies the required error ΔE, it is possible to reduce vibration while suppressing the effect on the pressure response.

[0073] As explained in the other setting method of the drive time T, the upper limit Tu of the drive time T may be set based on the pressure response curves La and Lc shown in Fig. 4. In this case, if the pressure error, which is an index showing the influence on the pressure response, is, for example, 6%, Tu becomes about 1 / 10 of the time constant τa. In other words, by setting the drive time T to T = 0.1 τa, it is possible to reduce vibration while suppressing the influence on the pressure response.

[0074] [4] In the pressure regulating vacuum valve described in [2] or [3] above, the opening control unit calculates the valve body drive time according to the volume of the chamber in which the pressure regulating vacuum valve is installed. The time constant τ is expressed as τ=V / Se(θ) from the chamber volume V and the effective exhaust speed Se(θ) of the exhaust system. Therefore, for example, when the drive time T is set to T=0.1τa, a more appropriate drive time T that reflects the device configuration can be set by using the time constant τa=V / Se(θ) using the actual volume V of the device chamber 2.

[0075] [5] In the pressure regulating vacuum valve described in any one of [2] to [4] above, the opening control unit sets the valve element drive speed and the valve element drive acceleration based on the valve element drive time. For example, based on the set drive time Tu, a drive pattern as shown on the right side of FIG. 9 is set. Specifically, S1b=B1·Tu, S2b=B2·Tu, S3b=B3·Tu, and vmaxb=2D(Δθa / Tu) are set. By setting in this way, the magnitude of the inclination of the hypotenuse of the trapezoidal pattern, that is, the absolute values ​​α1 and α3 of the acceleration in the sections S1b and S3b, can be made smaller than the conventional case shown on the left side of FIG. 9, and vibration can be reduced.

[0076] [6] In the pressure regulating vacuum valve described in [5] above, the opening control unit sets the valve body drive speed and the valve body drive acceleration based on the valve body drive time so that the sum of the acceleration drive time and the deceleration drive time is maximized. For example, as shown in Fig. 12, a drive pattern having a triangular shape may be adopted. By setting the drive pattern in this way, the sum of the acceleration drive time S1b and the deceleration drive time S3b can be maximized, and vibration when the valve body drive is stopped can be minimized.

[0077] [7] In the pressure regulating vacuum valve described in [6] above, it is preferable that the deceleration drive time is set longer than the acceleration drive time, thereby making it possible to further reduce vibration when the valve body is stopped.

[0078] [8] In the pressure regulating vacuum valve according to any one of the above items [5] to [7], the upper limit speed of the valve body drive speed is set to a speed corresponding to the upper limit drive capacity of the drive unit, thereby making it possible to reduce vibration and shorten the drive time.

[0079] [9] The pressure regulating vacuum valve described in any one of [2] to [8] above further comprises a calibration control unit that executes a calibration process to measure the volume of the chamber and the effective exhaust speed of the pressure regulating vacuum valve connected to the chamber, and in the calibration process, the valve body is driven for a drive time longer than the valve body drive time set by the opening control unit.

[0080] In the calibration process as shown in FIG. 14, the valve element opening θ(i) is changed to a plurality of values, and the effective exhaust speed S(θ) at each valve element opening θ(i) is calculated based on the pressure value P measured at each valve element opening θ(i). Since an error in the pressure measurement value P leads to an error in the effective exhaust speed S(θ), when acquiring the pressure measurement value P, it is necessary to sufficiently reduce the influence of vibrations caused by changing the opening on the pressure measurement value P. For this reason, it is preferable to set the drive time T when changing the opening in the calibration process to a drive time longer than the valve element drive time set by the opening control unit. For example, it is set to about four times the valve element drive time set by the opening control unit.

[0081]

[10] In the pressure regulating vacuum valve described in [1] above, the drive parameters are a valve body drive speed and a valve body drive acceleration when the valve body is driven, and the setting unit sets a maximum valve body drive power based on a maximum output power of an external power source that supplies power to the pressure regulating vacuum valve, and sets the valve body drive speed and the valve body drive acceleration so that the drive power is equal to or less than the maximum valve body drive power. For example, as in the process of steps S130 to S145 in Fig. 17, the maximum valve drive power is set based on the maximum possible output power of the external DC power supply 10, and the valve drive is controlled with drive parameters (vmaxn, αmaxn) that are equal to or less than the maximum possible output power at which the output voltage does not decrease. In this way, the drive parameters are set in accordance with the maximum possible output power of the external DC power supply 10, so that it is possible to prevent poor motor control in a slow-up section where the drive power is large, and the drive power is suppressed to reduce vibration.

[0082]

[11] In the pressure regulating vacuum valve described in

[10] above, the setting unit determines the maximum possible output power based on a drop in the supply voltage of the external power source when the valve body is driven, and sets the drive parameters based on the determination result. For example, as in the process of step S140 in Fig. 17, the maximum possible output power of the external DC power source 10 is determined based on whether or not the output voltage of the external DC power source 10 has dropped during the valve body drive operation.

[0083]

[12] In the pressure regulating vacuum valve described in [1] above, the drive parameters are a valve element drive speed and a valve element drive acceleration when the valve element is driven, and an input unit for inputting a drive parameter for reducing the valve element drive power is further provided, and the setting unit sets the drive parameter inputted by the input unit as the drive parameter for the valve element drive. For example, the drive parameter for reducing the valve element drive power may be set by a user operating the operation unit 76, or may be set by a command from the device controller 9 inputted via the external interface 73.

[0084] Although various embodiments and modifications have been described above, the present invention is not limited to these. For example, one or more of the modifications may be combined with the above-described embodiment. Other aspects that are conceivable within the scope of the technical idea of ​​the present invention are also included in the scope of the present invention. [Explanation of symbols]

[0085] 1...pressure regulating vacuum valve, 2...equipment chamber, 3...turbomolecular pump, 6...vacuum gauge, 7...valve controller, 8...TMP controller, 9...equipment controller, 10...external DC power supply, 11...valve plate, 12...motor, 71...drive unit, 72...control unit, 73...external interface, 74...communication unit, 75...power supply unit, 76...operation unit, 77...display unit

Claims

1. A valve body, A drive unit that drives the valve body to open and close; an opening control unit that controls an opening of the valve body driven by the drive unit; a setting unit that sets a valve element drive time from when drive starts from a first opening to when drive stops at a second opening, and sets a valve element drive speed and a valve element drive acceleration based on the valve element drive time, so that an estimated pressure error value during pressure control caused by the drive time of the valve element becomes a predetermined allowable value.

2. 2. The pressure regulating vacuum valve according to claim 1, The opening control unit calculates the valve body drive time according to the volume of a chamber in which the pressure regulating vacuum valve is installed.

3. 3. The pressure regulating vacuum valve according to claim 1, The opening control unit sets the valve body drive speed and the valve body drive acceleration based on the valve body drive time so that the sum of an acceleration drive time and a deceleration drive time is longest.

4. 4. The pressure regulating vacuum valve according to claim 3, The deceleration drive time is set to be longer than the acceleration drive time.

5. The pressure regulating vacuum valve according to any one of claims 1 to 4, A pressure regulating vacuum valve, wherein an upper limit speed of the valve body drive speed is set to a speed corresponding to an upper limit drive capacity of the drive unit.

6. The pressure regulating vacuum valve according to any one of claims 1 to 5, a calibration control unit that performs a calibration process to measure the volume of the chamber and the effective pumping speed of a pressure regulating vacuum valve connected to the chamber; In the calibration process, the valve element is driven for a drive time longer than a valve element drive time set by the opening control unit.

7. 2. The pressure regulating vacuum valve according to claim 1, The setting unit sets a maximum valve body drive power based on a maximum output power that can be output by an external power source that supplies power to the pressure regulating vacuum valve, and sets the valve body drive speed and the valve body drive acceleration so that the drive power is equal to or less than the maximum valve body drive power.

8. 8. The pressure regulating vacuum valve according to claim 7, The setting unit determines the maximum outputtable power based on a drop in the supply voltage of the external power source when the valve body is driven, and sets a valve body drive speed and a valve body drive acceleration based on the determination result.

9. 2. The pressure regulating vacuum valve according to claim 1, An input unit for inputting a valve disc drive speed and a valve disc drive acceleration is further provided, The setting unit sets the valve element drive speed and the valve element drive acceleration inputted by the input unit as the valve element drive speed and the valve element drive acceleration of the valve element drive.

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