JP2021167660A - Fluid control device - Google Patents

Abstract

To provide a fluid control device capable of increasing maximum flow rate more than conventional while keeping width dimension small.SOLUTION: A fluid control device includes: a first control valve V1 fitted to a block B; and a second control valve V2 fitted to a downstream side of the first control valve V1. An internal channel L is provided with: a joined passage CL where fluid passing the first control valve V1 or the second control valve V2 joins and flows; a first outflow port 12 where fluid flows from the first control valve V1; a first outflow passage EL1 connecting itself and the joined passage CL; a second outflow port 22 where fluid flows out of the second control valve V2; a second outflow passage EL2 connecting itself and the joined passage CL; and a second inflow passage SL2 connected to a second inflow port 21 where fluid flows in the second control valve V2. When the block B is seen through along the width direction, the first outflow passage EL1 and the second inflow passage SL2 overlap at one point.SELECTED DRAWING: Figure 1

Description

The present invention relates to a fluid control device that controls the flow rate and pressure of a fluid such as gas.

For example, a mass flow controller is used to control the flow rate of gas in a semiconductor manufacturing process. Some conventional mass flow controllers have a fluid control device such as a pressure sensor or a control valve attached to a block in which an internal flow path is formed. In order to compactly parallel a plurality of mass flow controllers, the above-mentioned block has an elongated rectangular parallelepiped shape extending in a predetermined width in the longitudinal direction (see Patent Document 1).

More specifically, the width dimension of the block is set to, for example, 10 mm by the standard. Further, a plurality of fluid control devices having substantially the same width dimension as the width dimension of the block are mounted side by side in the longitudinal direction on the mounting surface which is one surface parallel to the longitudinal direction of the block.

By the way, in recent years, not only is the mass flow controller compactly configured, but it is also required to be able to flow a larger flow rate than before. The maximum flow rate of the mass flow controller is almost limited by the flow rate that the control valve can flow. Therefore, for example, as shown in Patent Document 2, two internal flow paths are formed in parallel in the width direction in the block, and a control valve is provided in each internal flow path to approximately double the flow rate that can flow. It is conceivable to.

However, although the maximum flow rate can be increased in the above configuration, it is necessary to arrange two fluid control devices such as control valves in the width direction of the block, which makes it difficult to make the mass flow controller more compact. ..

WO2011 / 040270 Gazette Japanese Unexamined Patent Publication No. 2014-32635

The present invention has been made to solve the above-mentioned problems at once, and an object of the present invention is to provide a fluid control device capable of increasing the maximum flow rate as compared with the conventional one while keeping the width dimension small.

That is, the fluid control device according to the present invention has a block extending with a predetermined width along the longitudinal direction, an internal flow path formed in the block and extending along the longitudinal direction, and a first valve attached to the block. A control valve and a second control valve attached to the downstream side of the first control valve in the block are provided, and the internal flow path serves as a first outlet through which a fluid flows out from the first control valve. When a first outflow flow path to be connected and a second inflow flow path connected to a second inflow port where a fluid flows into the second control valve are provided, and the block is viewed through along the width direction. The first outflow flow path and the second inflow flow path are arranged so as to overlap at one point.

In such a case, the first control valve and the second control valve are arranged side by side along the longitudinal direction to reduce the width dimension of the block and allow the fluid flowing out from each control valve to merge. Can be flushed. Therefore, the maximum flow rate can be doubled by using two control valves while making the width dimension of the fluid control device compact.

Even if the width dimension of the block is small, in order to facilitate the arrangement of the first outflow flow path and the second inflow flow path at a twisted position so as not to interfere with each other in the block, the block is fluid-controlled. A mounting surface on which the device is mounted and a protruding portion protruding from the mounting surface by a predetermined amount are provided, and either the first control valve or the second control valve is attached to the mounting surface. Anything that can be attached will do.

In order to shorten the length of the internal flow path formed in the block as much as possible, reduce the internal volume, and improve the responsiveness of control, the second control valve is provided on the protruding portion. It should be. In such a case, when the fluid is introduced from the end surface of the block or the facing surface of the mounting surface, the length of the flow path for allowing the fluid to flow into the first control valve on the upstream side is shortened. Cheap.

As another embodiment for facilitating the arrangement of the first outflow flow path and the second inflow flow path at the twisted position while reducing the width dimension of the block, the first control valve is the block. A first valve block having a first contact surface in contact with the surface of the first valve block is provided, and the fluid flows out from the first inflow port into which the fluid flows into the first valve block and the first valve block. The first outlet is open to the first contact surface, and the second control valve includes a second valve block having a second contact surface in contact with the surface of the block. The second inflow port where the fluid flows into the second valve block and the second outflow port where the fluid flows out from the second valve block may open to the second contact surface. In such a case, the entire control valve may be arranged outside the block, and a recess or the like for accommodating a part of each control valve may not be formed in the block. As a result, it becomes easy to secure a space for forming the internal flow path in the block, and the degree of freedom in arranging the first outflow flow path and the second inflow flow path can be increased.

As a specific configuration example in which a large flow rate can be realized while being compact even if the width dimension of the block is the smallest, the first control valve and the second control valve have the same width dimension as the block. Things can be mentioned.

In order to be able to control the total flow rate of the fluid passing through the first control valve and the second control valve so as to be exactly a desired value, the internal flow path is the first control valve or the first control valve or the above. A second outflow that connects between the post-merging flow path in which the fluid that has passed through the second control valve merges and flows, the second outflow port from which the fluid flows out from the second control valve, and the post-merging flow path. A flow sensor further comprising a path, the downstream side of the first outflow flow path is connected to the post-merging flow path, and the flow sensor measures the flow rate of the fluid flowing through the post-merging flow path, and the flow rate sensor measures the flow. A fluid controller that controls at least one of the first control valve or the second control valve based on at least the flow rate may be further provided.

In another embodiment for achieving a desired flow rate as a whole by each control valve, the internal flow path is connected to a first inflow flow path in which a fluid flows into the first control valve. A flow rate sensor that further includes a first inflow flow path and a pre-branch flow path whose downstream side is connected to the second inflow flow path, and measures the flow rate of the fluid flowing through the pre-branch flow path, and the flow rate sensor. A fluid controller that further controls at least one of the first control valve and the second control valve based on at least the flow rate measured by is included.

In order to prevent the control of the fluid by the first control valve and the second control valve from interfering with each other and deteriorating the control performance, and to accurately realize the desired large flow rate, the fluid controller is used. However, the opening control unit that controls the opening degree of either the first control valve or the second control valve so that the shared target flow rate smaller than the set flow rate by a predetermined time flows, the set flow rate, and the flow rate. It suffices if it is provided with a flow rate feedback control unit that controls the first control valve or the other of the second control valve so that the deviation from the flow rate measured by the sensor becomes small.

For example, even if there is a fluctuation in the supply pressure, a flow rate close to the shared target flow rate can be realized by one control valve by controlling the opening control unit, and the load on the other control valve controlled by the flow rate feedback can be reduced. In order to do so, the opening degree control unit calculates the target opening degree corresponding to the shared target flow rate based on the pressure on the upstream side of the first control valve, and the target opening degree calculation unit and the target opening degree. It may be any one provided with a voltage control unit that applies a voltage corresponding to the above to the first control valve or the other of the second control valve.

In order to realize substantially the same flow rate in both the first control valve and the second control valve, and as a result, to enable a maximum flow rate about twice that of the conventional one in the entire fluid control device, the shared target flow rate is set. It suffices if it is set to 1/2 of the flow rate.

In order for each control valve to obtain a desired flow rate as a whole by a simple control rule, the fluid controller synchronizes the opening degree of the first control valve with the opening degree of the second control valve. Anything may be provided as long as it is provided with a synchronous control unit that controls the above.

The flow rate output from the fluid control device is maintained at the set flow rate even if there is a disturbance, while simplifying the control rule by allowing both the first control valve and the second control valve to operate in the same manner. The first control valve and the second control valve are of the same type, and the synchronous control unit controls the first control so that the deviation from the flow rate measured by the flow rate sensor becomes small. The same voltage may be applied to each of the valve and the second control valve.

In the normal state, the flow rate is controlled by either the first control valve or the second control valve, and even if an abnormality occurs in the control valve that controls the flow rate, the flow rate is sent to another control valve. In order to enable self-recovery from an abnormality by switching the control, the fluid controller may use the first control valve or the first control valve so that the deviation between the set flow rate and the flow rate measured by the flow rate sensor becomes small. The flow rate feedback control unit that controls one of the two control valves, the valve abnormality detection unit that detects an abnormality in the first control valve or the second control valve, and the valve abnormality detection unit provide the flow rate feedback. A control target switching unit that switches the control valve to be controlled by the flow feedback control unit when an abnormality of the first control valve or the second control valve controlled by the control unit is detected. It suffices as long as it is provided with.

In such a case, for example, if an abnormality occurs in the control valve that controls the flow rate without the operator performing a special return operation or repair operation, another control valve is automatically switched. Therefore, the flow rate control can be continued. Therefore, with such a fluid control device, even if one of the control valves fails, self-recovery and self-repair are possible, and the reliability of flow rate control can be improved. Further, for example, if the first control valve and the second control valve are of the normally open type, even if the control valve that first performed the flow rate control fails, the control valve will be in the fully open state and the control will be performed. It is unlikely to interfere with flow control by the switched control valve.

To improve the responsiveness by shortening the distance between the measurement point measured by the flow rate sensor and the flow rate control point by the control valve in the normal state where each control valve does not have a failure or the like. The flow rate feedback control unit controls the second control valve in the initial state, and when the valve abnormality detection unit detects an abnormality in the second control valve, the control target switching unit performs the flow rate feedback. Any device may be used as long as it is configured to switch the control target of the control unit to the first control valve.

As a specific configuration example for detecting an abnormality in each control valve, the valve abnormality detecting unit has an abnormality in the insulation state based on the voltage applied to the first control valve or the second control valve. Examples include those configured to detect.

As another configuration example for detecting an abnormality in each control valve, the valve abnormality detecting unit controls the first control based on an absolute value of a deviation between the set flow rate and the flow rate measured by the flow rate sensor. Examples thereof include those configured to detect an abnormality in the valve or the second control valve.

As described above, according to the fluid control device according to the present invention, when the block is viewed through along the width direction, the first outflow flow path and the second inflow flow path are arranged so as to overlap at one point. Therefore, the first control valve and the second control valve are arranged side by side in the longitudinal direction of the block, and the fluid passing through each control valve is passed through the flow path after merging while reducing the width dimension of the block. Can be merged at. As a result, the maximum flow rate can be increased as compared with the conventional case while the fluid control device is compactly configured.

The schematic diagram which shows the hardware structure of the fluid control apparatus in 1st Embodiment of this invention. The schematic diagram which shows the structure of the fluid controller of the fluid control apparatus in 1st Embodiment. The schematic fluid circuit diagram of the fluid control apparatus in 1st Embodiment. The schematic diagram which shows the hardware structure of the fluid control apparatus in 2nd Embodiment of this invention. The schematic diagram which shows the structure of the fluid control apparatus in 3rd Embodiment of this invention. The schematic fluid circuit diagram of the fluid control apparatus in 4th Embodiment of this invention. The schematic diagram which shows the structure of the fluid control apparatus in a normal state in 5th Embodiment of this invention. The schematic diagram which shows the structure of the fluid control apparatus at the time of the occurrence of abnormality in 5th Embodiment of this invention.

The fluid control device 100 of the first embodiment will be described with reference to FIGS. 1 to 3.

The fluid control device 100 is used, for example, in a semiconductor manufacturing process to supply various gases as a fluid to a chamber at a desired set flow rate. Further, a gas supply system is configured by arranging a plurality of fluid control devices 100 in parallel in the width direction.

As shown in FIGS. 1 and 2, the fluid control device 100 has a longitudinal direction with respect to a block B and a block B in which an internal flow path L through which gas flows from one end to the other end is formed. A pressure type flow sensor FM that measures the flow rate of gas after passing through the attached first control valve V1 and second control valve V2, the first control valve V1 or the second control valve V2, and merging, and a flow rate. It includes a fluid controller CB that controls the first control valve V1 and the second control valve V2 based on the measured value of the sensor FM. Each part will be described in detail.

As shown in FIG. 1, the block B has a rectangular parallelepiped-shaped protrusion B1 formed at the center of one side surface of an elongated rectangular parallelepiped. A side surface of the protruding portion B1 is set as a mounting surface AS to which the first control valve V1 which is a fluid control device and the first pressure sensor P1 and the second pressure sensor P2 constituting the flow rate sensor FM are mounted. Further, the protruding portion B1 is provided with a second control valve V2. That is, the first control valve V1, the second control valve V2, the first pressure sensor P1, and the second pressure sensor P2 are attached to the block B in order from the upstream side with respect to the internal flow path L. As shown in FIG. 1 (b), the block B has a constant width dimension, and the first control valve V1, the second control valve V2, the first pressure sensor P1, and the second pressure sensor P2 are also of the block B. It has almost the same dimensions as the width dimension.

The first control valve V1 and the second control valve V2 are, for example, piezo valves of the same type and type, and have a cylindrical shape composed of a valve seat and a valve body in a hollow cylindrical recess formed in the mounting surface AS or the protrusion B1. The valve structure is inserted, and the piezo actuator that drives the valve body is provided so as to project outward. Gas flows into the control valve from the inflow port formed on the lower surface side of the valve structure, and the gas passing through the gap between the valve body and the valve seat enters from the outflow port formed on the side surface of the valve structure. It flows to the downstream side. In the following description, the inlet and outlet of the first control valve V1 are referred to as the first inlet 11 and the first outlet 12, and the inlet and outlet of the second control valve V2 are referred to as the second inlet 21 and the outlet. It is called the second outlet 22.

The first pressure sensor P1 and the second pressure sensor P2 are of the same type and type, and are composed of a rectangular parallelepiped fixed portion attached to the mounting surface AS and a main body portion having a flat disk shape on the upper side of the fixed portion. Become. A pressure-sensitive surface of pressure is provided inside the main body so as to be perpendicular to the mounting surface AS. Further, the first pressure sensor P1 presses and fixes the laminar flow element R, which is a fluid resistance housed in the recess formed in the mounting surface AS by the lower surface of the fixing portion. This laminar flow origin is a stack of a plurality of laminar flow element plates on which minute flow paths are formed, and gas passes between the laminar flow element plates to generate a differential pressure before and after the laminar flow element R. A through hole is provided in the center of the laminar flow element R to guide the gas before passing between the laminar flow element plates into the first pressure sensor P1, and the first pressure sensor P1 is upstream of the laminar flow element R. Measure the pressure on the side. Further, the second pressure sensor P2 measures the pressure of the gas after passing through the laminar flow element R.

Further, on the bottom surface of the block B, which is the opposite surface of the mounting surface AS, the introduction port CIP into which the gas is introduced into the internal flow path L and the gas that has passed through the first control valve V1 or the second control valve V2 flow internally. A lead-out port COP led out from the path L to the outside is formed.

The portion of the internal flow path L formed on one end side of the block B is formed as two parallel flow paths. A first control valve V1 and a second control valve V2 are provided in each of the parallel flow paths. Further, the portion of the internal flow path L formed on the other end side of the block B is formed as one post-merging flow path CL to which the gas passing through the first control valve V1 or the second control valve V2 merges. There is.

That is, by attaching each fluid control device to one block B, a fluid circuit as shown in FIG. 3 is formed. More specifically, as shown in FIGS. 1 and 3, the internal flow path L is from the pre-branch flow path BBL into which the fluid flows from the introduction port CIP and the branch point BP at the downstream end of the pre-branch flow path BBL. The second control valve V2 branches from the first inflow flow path SL1 that branches and connects between the first inflow port 11 of the first control valve V1 and the branch point BP at the downstream end of the pre-branch flow path BBL. Between the second inflow flow path SL2 whose end is connected to the second inflow port 21 of the above, the first outflow port 12 of the first control valve V1 and the confluence point CP which is the upstream end of the post-merging flow path CL. The first outflow flow path EL1 to be connected and the second outflow flow path EL2 to be connected between the second outflow port 22 of the second control valve V2 and the confluence point CP which is the upstream end of the flow path CL after merging. Further prepared. Here, the second inflow flow path SL2 and the first outflow flow path EL1 are in twisted positions in the block B, respectively.

When the block B is seen through along the width direction as shown in FIG. 1A, the second inflow flow path SL2 and the first outflow flow path EL1 are arranged so as to overlap at one point. That is, a part of the first outflow flow path EL1 and the second inflow flow path SL2 are arranged so as to form a cross when viewed along the width direction. More specifically, the first inflow flow path SL1 is formed in the central portion in the width direction in the block B, but the second inflow flow path SL2 advances diagonally from the central portion in the width direction toward the back of the paper. ing. Further, since the second control valve V2 is provided on the protruding portion B1, the second inflow flow path SL2 travels toward the back of the paper surface in FIG. 1A, and is combined with the mounting surface from the bottom surface side of the block B. It is progressing to the AS side. In other words, the flow direction of the second inflow flow path SL2 travels in the block B in the diagonally back direction of the paper surface.

Further, the first outflow flow path EL1 advances from the front side of the paper surface in FIG. 1 (a) of the block B toward the central portion in the width direction, and proceeds from the mounting surface AS side to the bottom surface side, and the second outflow flow path Together with EL2, it reaches the tip of the merging flow path on the upstream side of the laminar flow element R.

Next, the fluid controller CB will be described with reference to FIG.

The fluid controller CB is a control circuit composed of a CPU, a memory, an I / O channel, an A / D converter, a D / A converter, and other analog or digital circuits. In the fluid controller CB, a program stored in the memory is executed by the CPU, and various devices cooperate to form the fluid controller CB as an opening control unit 2, a flow rate calculation unit 3, and a flow rate feedback control unit 4, at least as shown in FIG. Demonstrate the function of. In the fluid controller CB of the present embodiment, the same flow rate passes through the first control valve V1 and the second control valve V2, respectively, and a flow rate substantially the same as the set flow rate set by the user flows in the flow path CL after merging. The first control valve V1 and the second control valve V2 are controlled in this way. That is, by flowing substantially the same amount of gas from the first control valve V1 and the second control valve V2, it is possible to realize a maximum flow rate that is about twice as much as when there is only one control valve. Details of each part will be described below.

The opening degree control unit 2 is first based on the set flow rate and the gas supply pressure measured by a supply pressure sensor (not shown) provided in the flow path connected to the introduction port CIP of the fluid control device 100. The opening degree of the control valve V1 is controlled. That is, the opening degree control unit 2 controls the opening degree so that the flow rate of the gas passing through the first control valve V1 is 1/2 of the set flow rate. Here, the post-merging flow rate, which is the flow rate of the gas flowing through the post-merging flow path CL measured by the flow rate sensor FM, is not fed back to the opening degree control unit 2.

More specifically, the opening degree control unit 2 is calculated by the target opening degree calculation unit 21 that calculates the target opening degree of the first control valve V1 based on the set flow rate and the supply pressure, and the target opening degree calculation unit 21. A voltage control unit 22 for applying a voltage corresponding to the target opening degree to the first control valve V1 is provided.

The target opening degree calculation unit 21 holds information about the conductance of the first control valve V1 and calculates a target opening degree capable of realizing a flow rate of 1/2 of the set flow rate at the current supply pressure from this conductance.

The voltage control unit 22 holds information on the voltage-opening characteristic of the first control valve V1 and applies a voltage corresponding to the target opening degree to the first control valve V1.

As described above, in the control of the first control valve V1, the information regarding the flow rate realized by the first control valve V1 is not fed back, and the open loop control is performed for the flow rate based on the supply pressure and the set flow rate. Therefore, the flow rate of the gas output from the first control valve V1 is close to 1/2 of the set flow rate, but the flow rate error is not corrected and remains maintained.

The flow rate calculation unit 3 is the flow rate of the gas flowing through the flow path CL after merging based on the first pressure measured by the first pressure sensor P1 and the second pressure measured by the second pressure sensor P2 after merging. Calculate the flow rate. As the flow rate calculation formula used in the flow rate calculation unit 3, for example, a known one based on the difference between the first pressure and the second pressure and the difference between the square of the first pressure and the square of the second pressure is used.

The flow rate feedback control unit 4 controls the flow rate feedback of the opening degree of the second control valve V2 so that the deviation between the set flow rate and the flow rate after merging calculated by the flow rate calculation unit 3 becomes small. That is, both the flow rate error realized by the first control valve V1 and the flow rate error realized by the second control valve V2 are configured to be reduced by the control of the second control valve V2.

In the fluid control device 100 configured in this way, the first outflow flow path EL1 and the second control valve V2, in which the gas flows out from the first control valve V1 formed in the block B, are caused to flow the gas. 2 Since the inflow flow path SL2 is arranged at a twisted position and is arranged so as to overlap at one point when viewed along the width direction, the first outflow flow path EL1 and the first control valve V1 The second control valves V2 are arranged side by side along the longitudinal direction, and the fluid flowing out from the first control valve V1 and the second control valve V2 flows into the flow path CL after merging while reducing the width dimension of the block B. be able to. Therefore, the maximum flow rate can be doubled by using two control valves while making the width dimension of the fluid control device 100 compact.

Further, the opening degree of the first control valve V1 is controlled by the fluid controller CB based on the supply pressure, and the flow rate is controlled by an open loop. Further, the second control valve V2 feeds back the flow rate after merging measured by the flow rate sensor FM, and controls the flow rate in a closed loop. Since the flow rate feedback control is performed only on the second control valve V2 in this way, it is possible to prevent the control valves from interfering with each other.

Further, since the opening degree of the first control valve V1 is controlled so as to flow a flow rate corresponding to 1/2 times the set flow rate, the flow rate of the gas passing through the first control valve V1 and the second control valve V2 is substantially equal. Can be the same value. Therefore, it is possible to accurately control the maximum flow rate by about twice as compared with the case where the gas flow rate is controlled by one control valve.

Next, the fluid control device 100 according to the second embodiment of the present invention will be described with reference to FIG. The members corresponding to the members described in the first embodiment are designated by the same reference numerals.

The fluid control device 100 of the second embodiment is configured such that the valve body, valve seat, etc. of the first control valve V1 and the second control valve V2 are not inserted into the block B, and each of them is separated from each other. Has been done.

Specifically, the first control valve V1 includes a first valve block VB1 in which a valve body and a valve seat are formed inside, and the lower surface of the first valve block VB1 is relative to the mounting surface AS of the block B. It is attached and configured to communicate with the internal flow path L. That is, in the first valve block VB1, the connection surface CS formed on the lower surface is opened with a first inflow port 11 into which the gas as a fluid flows in and a first outflow port 12 in which the gas flows out from the inside. .. Therefore, by bringing the connection surface CS into contact with the mounting surface AS, the downstream end opening of the first inflow flow path SL1 and the first inflow port 11 that open to the mounting surface AS as shown in FIG. 4A. Communicate with the upstream end opening of the first outflow flow path EL1 that opens to the mounting surface AS and the first outflow port 12. As shown in FIG. 4B, the first outflow port 12 is arranged so as to be offset in the width direction with respect to the center of the first inflow port 11, and is aligned with the first outflow flow path EL2 extending obliquely in the block B. Be connected.

Further, the second control valve V2 also has the same structure as the first control valve V1. The second control valve V2 includes a second valve block VB2 in which a valve body and a valve seat are formed therein, and the lower surface of the second valve block VB2 is attached to the mounting surface AS of the block B. It is configured to communicate with the internal flow path L. That is, in the second valve block VB2, the second inflow port 21 into which the gas as a fluid flows into the inside and the second outflow port 22 from which the gas flows out from the inside are opened in the connection surface CS formed on the lower surface. .. Therefore, by bringing the connection surface CS into contact with the mounting surface AS, the downstream end opening of the second inflow flow path SL2 and the second inflow port 21 that open to the mounting surface AS as shown in FIG. 4A. Communicate with the upstream end opening of the second outflow flow path EL2 that opens to the mounting surface AS and the first outflow port 22. As shown in FIG. 4B, the second outlet 22 is arranged so as to be offset toward the center in the width direction with respect to the center of the first outlet 12. The second outflow flow path EL2 connected to the second outflow port 22 extends in the height direction of the block B and is formed so as to intersect the first outflow flow path 12.

The second inflow flow path SL2 extends diagonally from the central portion of the block B toward the back side in the width direction, and is arranged at a twisted position with the first outflow flow path EL2 extending diagonally toward the front side in the width direction. It is set to. Further, as shown in FIG. 4A, when the block B is seen through in the width direction, the first outflow flow path EL1 and the second inflow flow path SL2 are configured to overlap at one point.

In the fluid control device 100 of the second embodiment configured in this way, a recess for accommodating a part of the first control valve V1 and the second control valve V2 with respect to the mounting surface AS of the block B. The entire control valves V1 and V2 can be arranged outside the block B and separated from each other. Therefore, it is possible to take a large space in the block B where the first inflow flow path SL1, the second inflow flow path SL2, the first outflow flow path EL1, and the second outflow flow path EL2 can be formed. Therefore, even if the shape is simple, it is easy to easily arrange the first outflow flow path EL1 and the second inflow flow path SL2 at the twisted position.

Next, the fluid control device 100 according to the third embodiment of the present invention will be described with reference to FIG. The members corresponding to the members described in the first embodiment are designated by the same reference numerals.

In the fluid control device 100 of the third embodiment, the configuration of the fluid controller CB is different from that of the first embodiment. That is, the fluid controller CB of the first embodiment independently controls the first control valve V1 and the second control valve V2 according to different control rules, whereas the fluid controller CB of the third embodiment is the first. The opening degree of the control valve V1 and the second control valve V2 is changed in synchronization with each other.

Specifically, the fluid controller CB includes a synchronization control unit 5 that controls the opening degree of the first control valve V1 and the opening degree of the second control valve V2 so as to be synchronized with each other.

The synchronous control unit 5 applies the same voltage to each of the first control valve V1 and the second control valve V2 so that the deviation from the flow rate after merging measured by the flow rate sensor FM becomes small. Here, since the first control valve V1 and the second control valve V2 are of the same type and the same type, if the same voltage is applied, the opening degree will be substantially the same. Further, the synchronous control unit 5 changes the voltage applied to each control valve V1 according to the deviation between the set flow rate and the measured flow rate, but the value of the voltage applied at each time is substantially the same. It is configured. That is, the first control valve V1 and the second control valve V2 are connected to the synchronous control unit 5 in parallel, for example, and the voltage values applied to them are always the same. Further, the synchronous control unit 5 is configured to correct the magnitude of the voltage applied according to the supply pressure.

With the fluid control device 100 of the third embodiment as described above, it is possible to allow gas to flow evenly to each of the control valves V1 and V2, although it is a simple control rule, and it is possible to realize a large flow rate with high accuracy.

Next, the fluid control device 100 according to the fourth embodiment of the present invention will be described with reference to FIG. The members corresponding to the members described in the first embodiment are designated by the same reference numerals.

In the fluid control device 100 of the fourth embodiment, the flow rate sensor FM is provided on the pre-branch flow path BBL on the upstream side of the control valves V1 and V2, and the flow rate sensor FM is not a pressure type but a thermal type. Flow sensor is used. The flow rate sensor FM includes a fluid resistance R provided in the pre-branch flow path BBL, a U-shaped thin tube TP that bypasses the fluid resistance R, a first coil C1 wound outside the thin tube TP, and a first coil. A second coil C2, which is provided on the downstream side of the one coil C1 and is wound outside the thin tube TP, is provided. For example, the fluid controller CB applies a voltage so that the temperatures of the coils C1 and C2 are kept constant, and the flow rate is calculated based on the difference between the voltages applied to the coils C1 and C2.

Even with such a fluid control device 100 of the fourth embodiment, it is possible to enjoy substantially the same effect as that of the fluid control device 100 of the first embodiment.

Next, the fluid control device 100 according to the fifth embodiment of the present invention will be described with reference to FIGS. 7 and 8. The members corresponding to the members described in the first embodiment are designated by the same reference numerals.

In the fluid control device 100 of the fifth embodiment, the flow rate control is automatically continued even if a failure or the like occurs in either the first control valve V1 or the second control valve V2. That is, the fluid control device 100 has a self-restoring and self-repairing function with respect to the flow rate control.

Specifically, the first control valve V1 and the second control valve V2 in the fluid control device 100 are configured as normally open type valves. In other words, the first control valve V1 and the second control valve V2 are configured to be fully opened when no voltage is applied or when dielectric breakdown occurs in the piezo actuator. In addition, the first control valve V1 and the second control valve V2 are control valves of the same type and have substantially the same control characteristics.

Further, as shown in FIG. 7, the fluid controller CB normally controls the flow rate only by the second control valve V2, and as shown in FIG. 8, automatically controls the flow rate by only the first control valve V1 when an abnormality occurs. It is configured to switch. That is, in the normal state, the opening degree of the second control valve V2 is appropriately changed, whereas the first control valve V2 is kept in a fully open state, for example.

Specifically, the fluid controller CB is configured to function as a flow rate calculation unit 3, a flow rate feedback control unit 4, a valve abnormality detection unit 6, and a flow rate control switching unit 7.

Since the flow rate calculation unit 3 has the same configuration as that of the first embodiment, the description thereof will be omitted. The flow rate feedback control unit 4 has the same basic control rules as those in the first embodiment, but the flow rate control switching unit 7 switches the control valve to be controlled. Further, in this embodiment, the flow rate feedback control unit 4 normally controls the second control valve V2, and controls the first control valve V1 when an abnormality occurs.

The valve abnormality detection unit 6 monitors at least the second control valve V2, which is normally controlled by the flow rate feedback control unit 4. That is, the valve abnormality detecting unit 6 monitors the value of the voltage applied to the second control valve V2, and also obtains the absolute value of the deviation between the set flow rate calculated by the flow rate feedback control unit 4 and the flow rate after merging. I'm monitoring. The valve abnormality detection unit 6 determines that the piezo actuator has dielectric breakdown when, for example, the voltage applied to the second control valve V2 becomes equal to or less than a predetermined value. Further, the valve abnormality detection unit 6 determines that the flow rate cannot be controlled due to the abnormality of the second control valve V2 when the absolute value of the deviation described above becomes equal to or more than a predetermined value and the state is maintained for a predetermined period. do.

When the valve abnormality detecting unit 6 detects an abnormality in the second valve V2, the flow rate control switching unit 7 switches from the second control valve V2 to the flow rate control by the first control valve V1 as shown in FIG. That is, the flow rate feedback control unit 4 applies a voltage only to the first control valve V1, and the flow rate control is continued. Further, since the second control valve V2 to which no voltage is applied is a normally open type, the fully open state is maintained.

As described above, in the fluid control device 100 of the fifth embodiment, if an abnormality is detected in the second control valve V2 during the flow rate control by the second control valve V2 alone, the first control is automatically performed. It is possible to switch to the flow rate control with the valve V2. Therefore, even if the flow rate control cannot be continued due to the abnormality of the second control valve V2 and the set flow rate cannot be maintained, the flow rate control by the first control valve V1 can be started and the set flow rate can be self-returned.

Further, since the second control valve V2 is maintained in the fully open state after the flow rate control by the first control valve V1 is started, the flow path resistance by the second control valve V2 itself can be minimized. Therefore, the flow rate control by the first control valve V1 can be performed under substantially the same conditions as the second control valve V2, and the flow rate control accuracy and the like can be kept constant.

Other embodiments will be described.

The block may not have a protrusion that protrudes with respect to the mounting surface. That is, the first control valve and the second control valve may be mounted on mounting surfaces having the same height. Even in such a case, the first outflow flow path and the second inflow flow path may be arranged so as to be in a twisted position and intersect at one point when viewed along the width direction.

Further, the position where the protrusion is provided is not limited to that shown in the above embodiment. For example, a protrusion may be provided at a position where the first control valve is provided so that the first control valve is arranged at a higher position in the block than the second control valve.

The flow rate sensor is not limited to the pressure type flow rate sensor, and may be based on other measurement principles such as a thermal type or an ultrasonic type. Further, the fluid flowing through the internal flow path may be a liquid as well as a gas.

The control valve to be controlled by the opening degree control unit is not limited to the first control valve, and may be a second control valve. In such a case, the flow rate feedback control unit may be configured to control the first control valve. In addition, the pressure used in the opening degree control unit is not limited to the supply pressure. For example, the opening degree control unit may control the opening degree of the first control valve or the second control valve based on the first pressure measured by the first pressure sensor constituting the pressure type flow rate sensor.

The opening degree control unit is not limited to the one that operates so as to realize a flow rate that is 1/2 times the set flow rate. For example, the first control valve or the second control valve may be controlled so as to realize a flow rate smaller than a predetermined flow rate by a predetermined time.

The fluid control device is not limited to the one that controls the flow rate, and may be the one that controls the pressure. With the fluid control device according to the present invention, the maximum flow rate can be made larger than before even when the pressure is controlled.

The second inflow flow path is not limited to the one branching from the first inflow flow path, and may be formed so as to connect between the introduction port and the second inflow port. Further, two introduction ports may be provided so that the first inflow flow path and the second inflow flow path receive fluid supply from different fluid supply sources.

In the fifth embodiment, the flow rate is normally controlled only by the second control valve, and after an abnormality is detected, the flow rate is controlled only by the first control valve. However, the first control valve is normally used. The flow rate may be controlled only by the second control valve, and after an abnormality is detected, the flow rate may be controlled only by the second control valve. Further, for the control valve whose flow rate is not controlled in the normal state, an operation maintenance voltage may be applied so that the control valve can be operated immediately after switching. Further, for a control valve that does not normally perform flow rate control, for example, pressure control may be performed, and flow rate control may be performed after an abnormality is detected.

In addition, the fluid control device of the fifth embodiment is not limited to the one in which both the first control valve and the second control valve are configured as a normally open type, and the voltage of the first control valve and the second control valve is increased. When it is not applied, it may be configured as a normally closed type that is kept in a fully closed state. Further, one of the first control valve and the second control valve may be configured as a normally open type and the other as a normally closed type. Even with these configurations, if an abnormality occurs in the control valve that was controlling the flow rate, the flow rate control by another control valve can be automatically continued. Therefore, the self-recovery and self-repair functions can be realized for the flow rate control as described in the fifth embodiment.

In addition, as long as it does not contradict the gist of the present invention, various embodiments may be modified or some of the embodiments may be combined with each other.

100 ... Fluid control device V1 ... 1st control valve V2 ... 2nd control valve SL1 ... 1st inflow flow rate SL2 ... 2nd inflow flow rate EL1 ... 1st outflow flow rate EL2 ・ ・ ・ 2nd outflow flow path FM ・ ・ ・ Flow rate sensor CB ・ ・ ・ Fluid controller 2 ・ ・ ・ Opening control unit 21 ・ ・ ・ Target opening calculation unit 22 ・ ・ ・ Voltage control unit 3 ・ ・ ・Flow rate calculation unit 4 ・ ・ ・ Flow rate feedback control unit 5 ・ ・ ・ Synchronous control unit 6 ・ ・ ・ Valve abnormality detection unit 7 ・ ・ ・ Flow rate control switching unit

Claims (16)

A block that extends in a predetermined width along the longitudinal direction,
An internal flow path formed in the block and extending along the longitudinal direction,
The first control valve attached to the block and
A second control valve mounted on the downstream side of the first control valve is provided.
The internal flow path
A first outflow flow path connected to a first outflow port from which the fluid flows out from the first control valve,
A second inflow flow path connected to a second inflow port through which a fluid flows into the second control valve is provided.
A fluid control device in which the first outflow flow path and the second inflow flow path are arranged so as to overlap at one point when the block is viewed through along the width direction. The block
The mounting surface on which the fluid control equipment is mounted and
A protrusion that protrudes by a predetermined amount with respect to the mounting surface is provided.
The fluid control device according to claim 1, wherein either the first control valve or the second control valve is attached to the mounting surface. The fluid control device according to claim 2, wherein the second control valve is provided on the protruding portion. The first control valve includes a first valve block formed with a first contact surface that contacts the surface of the block, a first inflow port into which a fluid flows into the first valve block, and the above. The first outlet through which the fluid flows out from the first valve block is open to the first contact surface.
The second control valve includes a second valve block formed with a second contact surface that contacts the surface of the block, the second inflow port into which a fluid flows into the second valve block, and the second inflow port. The fluid control device according to claim 1, wherein the second outlet through which the fluid flows out from the second valve block opens to the second contact surface. The fluid control device according to any one of claims 1 to 4, wherein the first control valve and the second control valve have the same width dimension as the block. The internal flow path
A post-merging flow path through which fluids that have passed through the first control valve or the second control valve merge and flow.
A second outflow port from which the fluid flows out from the second control valve and a second outflow flow path connecting between the merging flow path are further provided, and the downstream side of the first outflow flow path is after the merging. It is connected to the flow path and
A flow rate sensor that measures the flow rate of the fluid flowing through the flow path after merging,
The fluid control device according to any one of claims 1 to 5, further comprising a fluid controller that controls at least one of the first control valve and the second control valve based on at least the flow rate measured by the flow rate sensor. The internal flow path
A first inflow flow path connected to a first inflow port through which a fluid flows into the first control valve,
The downstream side is further provided with the first inflow flow path and the pre-branch flow path connected to the second inflow flow path.
A flow rate sensor that measures the flow rate of the fluid flowing through the pre-branch flow path,
The fluid control device according to any one of claims 1 to 5, further comprising a fluid controller that controls at least one of the first control valve and the second control valve based on at least the flow rate measured by the flow rate sensor. The fluid controller
An opening control unit that controls the opening degree of either the first control valve or the second control valve so that a shared target flow rate smaller than a predetermined flow rate of the set flow rate flows.
6. 7. The fluid control device according to 7. The opening control unit
A target opening degree calculation unit that calculates a target opening degree corresponding to the shared target flow rate based on the pressure on the upstream side of the first control valve.
The fluid control device according to claim 8, further comprising a voltage control unit that applies a voltage corresponding to the target opening degree to the first control valve or the other of the second control valve. The fluid control device according to claim 8 or 9, wherein the shared target flow rate is set to 1/2 times the set flow rate. The fluid controller
The fluid control device according to claim 6 or 7, further comprising a synchronous control unit that controls the opening degree of the first control valve and the opening degree of the second control valve so as to be synchronized with each other. The first control valve and the second control valve are of the same type.
The fluid control according to claim 11, wherein the synchronous control unit applies the same voltage to each of the first control valve and the second control valve so that the deviation from the flow rate measured by the flow rate sensor becomes small. Device. The fluid controller
A flow rate feedback control unit that controls either the first control valve or the second control valve so that the deviation between the set flow rate and the flow rate measured by the flow rate sensor becomes small.
A valve abnormality detection unit that detects an abnormality in the first control valve or the second control valve,
When the valve abnormality detection unit detects an abnormality in the first control valve or the second control valve controlled by the flow rate feedback control unit, the control valve to be controlled by the flow rate feedback control unit is used. The fluid control device according to claim 6, further comprising a control target switching unit for switching. The flow rate feedback control unit controls the second control valve in the initial state.
When the valve abnormality detection unit detects an abnormality in the second control valve, the control target switching unit is configured to switch the control target of the flow rate feedback control unit to the first control valve. Item 13. The fluid control device according to item 13. The fluid control device according to claim 13 or 14, wherein the valve abnormality detecting unit is configured to detect an abnormality in an insulating state based on a voltage applied to the first control valve or the second control valve. .. The valve abnormality detecting unit is configured to detect an abnormality in the first control valve or the second control valve based on an absolute value of a deviation between the set flow rate and the flow rate measured by the flow rate sensor. The fluid control device according to any one of claims 13 to 15.

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