JP5216433B2 - Vacuum exhaust apparatus and vacuum exhaust method - Google Patents

Description

  The present invention relates to a vacuum exhaust apparatus and a vacuum exhaust method for exhausting a vacuum container to a vacuum using an oil rotary vacuum pump.

2. Description of the Related Art Conventionally, various evacuation apparatuses that evacuate a vacuum container that requires a high degree of vacuum using an oil rotary pump, such as a scanning electron microscope and a space environment test apparatus, are known.
And in the conventional vacuum exhaust apparatus, the inconvenience which the oil, oil vapor, etc. of an oil rotary pump back flow in a vacuum vessel is prevented (for example, refer patent document 1 or patent document 2).

In the device described in Patent Document 1, an oil rotary pump is connected in series to a turbo molecular pump that is connected to a vacuum vessel via an inlet valve and exhausts the inside of the vacuum vessel to a high vacuum. A container vacuum gauge for measuring the degree of vacuum in the vacuum container and an exhaust vacuum gauge for measuring the degree of vacuum on the vacuum container side of the turbo molecular pump are provided. And according to the measured value of a container vacuum gauge and an exhaust vacuum gauge, the structure which controls the drive of a turbo molecular pump and an oil rotary pump, and the opening and closing of an exhaust valve and an inlet valve by the control means is taken.
However, in the thing of this patent document 1, since two expensive vacuum gauges are used, there exists a possibility that reduction of an apparatus cost cannot be obtained easily.

In the device described in Patent Document 2, a preliminary chamber that repeats air and vacuum is connected via a gate valve to an observation chamber for observing a sample in a scanning electron microscope. In addition, an oil rotary pump connected to the observation chamber via a roughing piping valve is also connected to the spare chamber via a preliminary chamber roughing piping valve. And the structure which provides the structure which introduce | transduces a vacuum gauge and minute gas between the reserve room and the reserve room roughing piping valve is taken.
However, in the thing of this patent document 2, when the opening and closing operation of a valve is inadequate, or when the reserve chamber is at the time of high vacuum exceeding the capability of the oil rotary pump, the oil or oil vapor of the oil rotary pump is There is a risk of backflow into the reserve room. In addition, a configuration in which a gas is separately circulated is required, and the gas is always exhausted during observation, which may make it difficult to simplify the device configuration and reduce the observation cost.

JP-A-5-44643 JP 2003-157786 A

  As described above, the conventional evacuation apparatus as described in Patent Document 1 and Patent Document 2 has a problem that it is difficult to simplify the device configuration and reduce the device cost.

  In view of the above, an object of the present invention is to provide a vacuum evacuation device and a vacuum evacuation method that can easily reduce the apparatus cost with a simple configuration.

Evacuation device of the present onset Ming, a vacuum exhaust system connected to the vacuum vessel to evacuate the vacuum container is evacuated, and an oil rotary vacuum pump connected to said vacuum chamber for evacuating the vacuum vessel to a vacuum , a pair of opening and closing valve provided in a serial manner between the vacuum container and the oil-rotary vacuum pump, a vacuum gauge for measuring the vacuum degree is provided located between the opening and closing valves, measuring at the vacuum gauge Control means for controlling the open / closed state of the pair of open / close valves based on the degree of vacuum, and the control means is connected to the vacuum vessel side when the oil rotary vacuum pump is driven. Vessel vacuum degree data relating to the degree of vacuum in the vacuum vessel measured by the vacuum gauge with the valve opened for a predetermined period is stored, and after the one on-off valve is closed, the oil rotary vacuum pump side The other open / close valve to be continued is opened, and the pump vacuum degree data relating to the vacuum degree on the oil rotary vacuum pump side measured by the vacuum gauge is obtained, and the vacuum degree data on the oil rotary vacuum pump side is obtained and stored. The degree of vacuum of the pump vacuum degree data relating to the vacuum degree on the oil rotary vacuum pump side by comparing the container vacuum degree data and the pump vacuum degree data relating to the vacuum degree on the oil rotary vacuum pump side measured by the vacuum gauge , When the degree of vacuum is greater than the degree of vacuum stored in the stored vacuum container, the evacuation process of opening the pair of on-off valves is controlled .
In this invention, a pair of on-off valves are provided in series between a vacuum vessel and an oil rotary vacuum pump that evacuates the inside of the vacuum vessel, and a vacuum gauge for measuring the degree of vacuum is provided between these on-off valves. Yes. Then, the degree of vacuum in the vacuum container can be measured by opening only one open / close valve connected to the vacuum container side, and only the other open / close valve connected to the oil rotary vacuum pump side is opened. The degree of vacuum on the oil rotary vacuum pump side can be measured, and by opening both of them, the state of the degree of vacuum exhausted to a vacuum can be measured while exhausting the inside of the vacuum vessel to a vacuum.
As a result, even with a single vacuum gauge, it is possible to measure the appropriate degree of vacuum while preventing the inconvenience of oil or oil vapor from the oil rotary vacuum pump from flowing into the vacuum vessel, resulting in a simplified configuration and equipment cost. Can be easily reduced.
In the present invention, the control means controls the open / closed state of the pair of open / close valves based on the degree of vacuum measured by the vacuum gauge.
As a result, inconveniences such as oil or oil vapor from the oil rotary vacuum pump flowing into the vacuum vessel due to erroneous operation by the operator can be prevented, and the open / close valve is automatically opened and closed, so that the vacuum is exhausted. Workability can be improved.
Furthermore, in the present invention, when the oil rotary vacuum pump is driven by the control means, the evacuation process is controlled. That is, the control means opens and opens one open / close valve connected to the vacuum container side, acquires and stores the container vacuum degree data related to the vacuum degree in the vacuum container measured by the vacuum gauge, and then closes one open / close valve. Then, the other open / close valve connected to the oil rotary vacuum pump side is opened, and the pump vacuum degree data relating to the vacuum degree on the oil rotary vacuum pump side measured by the vacuum gauge is acquired. After this, the control means compares the stored container vacuum data with the pump vacuum data relating to the vacuum degree on the oil rotary vacuum pump side measured by the vacuum gauge, and the pump vacuum degree relating to the vacuum degree on the oil rotary vacuum pump side. When it is recognized that the degree of vacuum in the data is greater than the degree of vacuum stored in the stored vacuum container, the pair of on-off valves are opened and vacuum is driven by the oil rotary vacuum pump that is driven. The container is evacuated to vacuum.
As a result, the inside of the vacuum vessel can be appropriately evacuated with one vacuum gauge without causing inconvenience such as oil or oil vapor from the oil rotary vacuum pump flowing into the vacuum vessel.
Here, the drive of the oil rotary vacuum pump is recognized by, for example, power supply or operation of a power switch, or the setting input by a switch operation requesting the drive of the oil rotary vacuum pump, etc. It may be automatic or manual, such as automatically recognizing the oil and starting to drive the oil rotary vacuum pump.

Then, a vacuum exhaust system of the present onset bright, the control means of the second on-off valve in acquiring pump vacuum data about the vacuum degree of the oil-rotary vacuum pump to get measured by the vacuum gauge It is preferable that the open state is a predetermined period.
In the present invention, the control means opens the other on-off valve for a predetermined period, and obtains pump vacuum data relating to the degree of vacuum on the oil rotary vacuum pump side, which is measured and obtained by a vacuum gauge. That is, after acquiring the pump vacuum data relating to the degree of vacuum on the oil rotary vacuum pump side, the other open / close valve is temporarily closed, and then the pair of open / close valves are opened, and the vacuum container is driven by the oil rotary vacuum pump to be driven. The inside is evacuated to vacuum.
Thus, it is possible to easily recognize the level of degree of vacuum of the vacuum and the vacuum container side of the oil-rotary pump side with a simple configuration of a pair of opening and closing valves and vacuum gauge, and later both off valve Even if they are opened at the same time, it is possible to prevent the air on the oil rotary vacuum pump side containing oil or oil vapor harmful to the vacuum vessel from flowing into the vacuum vessel side.

Further, in the vacuum exhaust system of the present onset Ming, the control means is determined by the vacuum gauge the pair of opening and closing the valve as opened after obtaining the pump vacuum data about the vacuum degree of the oil-rotary vacuum pump the When it is recognized that the degree of vacuum in the vacuum vessel has reached a predetermined degree, it is preferable that the other opening / closing valve is closed.
In this invention, after acquiring pump vacuum data related to the degree of vacuum on the oil rotary vacuum pump side by the control means, the pair of on-off valves are opened to evacuate the vacuum container, and vacuum container data measured by a vacuum gauge is measured. When it is recognized that the value of the degree of vacuum in the vacuum container is a predetermined degree of vacuum such as a preset threshold value, the other open / close valve is closed.
As a result, even if the operation of the oil rotary vacuum pump is stopped, the vacuum state is monitored by a vacuum gauge without causing inconvenience such as oil or oil vapor from the oil rotary vacuum pump flowing into the vacuum vessel. However, the maintenance of the vacuum state in the vacuum vessel can be prolonged. Moreover, the operating cost for maintaining the vacuum container in a vacuum state by stopping the operation of the oil rotary vacuum pump can be reduced. Furthermore, for example, when performing calibration in a precision instrument using a vacuum vessel, problems such as complicated calibration operations due to vibrations caused by driving of the oil rotary vacuum pump and reduced calibration accuracy may be caused. It can also be prevented by stopping the driving of the pump.

Further, a vacuum exhaust system of the present onset Ming, the control means, the oil-rotary vacuum the second on-off valve after the control of the closed state after the vacuum degree of the vacuum container reaches a predetermined degree of vacuum It is preferable that the pump can be stopped.
In the present invention, the control means can stop the operation of the oil rotary vacuum pump after the control of closing the other open / close valve after the degree of vacuum in the vacuum container reaches a predetermined degree of vacuum, for example, automatically Control to stop the drive or control to cut off the supplied power according to a manual stop operation is performed.
As a result, it is possible to reliably prevent inconveniences such as oil or oil vapor from the oil rotary vacuum pump flowing into the vacuum container due to the stop of the oil rotary vacuum pump in a state where the vacuum container and the oil rotary vacuum pump communicate with each other. .

Further, in the vacuum exhaust system of the present onset Ming, the control means, wherein when the degree of vacuum in the vacuum vessel is driven the oil-rotary vacuum pump is stopped by drops, the one opening and closing of the The container vacuum degree data relating to the degree of vacuum in the vacuum vessel measured by the vacuum gauge when the valve is open and the other open / close valve is closed is stored. After the valve is closed, the other open / close valve is opened, and the stored container vacuum data is compared with the pump vacuum data related to the vacuum on the oil rotary vacuum pump side that is sequentially measured by the vacuum gauge. Thus, the degree of vacuum in the pump vacuum degree data relating to the degree of vacuum on the oil rotary vacuum pump side is a degree of vacuum greater than the degree of vacuum in the stored vacuum vessel. It recognizes that it is desirable to employ an arrangement for the control of the vacuum re-exhaust process to the one of the opening and closing valve opened.
In this invention, the vacuum re-evacuation process is controlled by the control means when driving the oil rotary vacuum pump that is stopped in a state where the degree of vacuum in the vacuum vessel is reduced, that is, gradually approaches atmospheric pressure. . That is, the control means stores the container vacuum degree data relating to the degree of vacuum in the vacuum container measured by a vacuum gauge with one open / close valve open and the other open / close valve closed, and then closes one open / close valve. After the state, the other open / close valve is opened, and the pump vacuum degree data relating to the vacuum degree on the oil rotary vacuum pump side is sequentially measured and acquired by a vacuum gauge, and the stored container vacuum degree data relating to the vacuum degree in the vacuum vessel, The pump vacuum degree data on the vacuum degree on the oil rotary vacuum pump side obtained by sequentially measuring is compared. And when the control means recognizes that the degree of vacuum on the oil rotary vacuum pump side that is sequentially measured by a vacuum gauge is a degree of vacuum greater than the degree of vacuum in the vacuum vessel stored in advance, One open / close valve is opened, and the pair of open / close valves is opened, so that the inside of the vacuum vessel is evacuated to a vacuum by the driven oil rotary vacuum pump.
As a result, even in the case of re-evacuation, the inside of the vacuum vessel can be appropriately evacuated with one vacuum gauge without causing inconvenience such as oil or oil vapor from the oil rotary vacuum pump flowing into the vacuum vessel. .

Then, a vacuum exhaust system of the present onset bright, the a vacuum chamber and branching between the one of the opening and closing valve to be connected to the vacuum container side, between the vacuum container and the one of the opening and closing valve by the opening to the atmospheric pressure It is preferable to have a configuration including a leak portion including a leak valve for leaking.
According to the present invention, a leak portion having a leak valve that leaks to the atmospheric pressure between the vacuum vessel and the one on-off valve by opening is formed between the vacuum vessel and one on-off valve connected to the vacuum vessel side. .
As a result, when returning the inside of the vacuum vessel from the vacuum state to the atmospheric pressure state, the leakage valve is opened after opening one on-off valve, so that the gap between the vacuum vessel side and the other on-off valve is reduced. It becomes an atmospheric pressure state. After that, when the other opening / closing valve is opened, the air on the vacuum vessel side in the atmospheric pressure state flows into the oil rotary vacuum pump side. Therefore, the oil rotary vacuum pump may be stopped thereafter. For this reason, it is possible to prevent air on the oil rotary vacuum pump side containing harmful oil and oil vapor from flowing into the vacuum vessel and the vacuum gauge through the other opening / closing valve. Therefore, the inside of the vacuum vessel can be satisfactorily returned to the atmospheric pressure state by an easy process with a simple configuration.

Further, a vacuum exhaust system of the present onset Ming, the control means, the leak valve and the open state the second on-off valve connected to the oil-rotary vacuum pump after the closed state, measured by the vacuum gauge When recognizing that the degree of vacuum in the vacuum container has become almost atmospheric pressure, the other opening / closing valve is opened, and the leak process is controlled to stop driving the oil rotary vacuum pump. preferable.
In the present invention, the leak valve is opened after the other open / close valve is closed as control of the leak processing by the control means. For example, a manual opening process of the leak valve or an automatic opening process of the leak valve by the control means is performed. Further, when recognizing that the degree of vacuum in the vacuum vessel measured by the vacuum gauge has become almost atmospheric pressure, the control means opens the other opening / closing valve to leak the oil rotary vacuum pump side to atmospheric pressure. Then, the control means stops driving the oil rotary vacuum pump. For example, a control for automatically stopping the driving or a control for enabling the supply power to be cut off in accordance with a manual stopping operation is performed.
As a result, even when the inside of the vacuum vessel is leaked to atmospheric pressure, the vacuum vessel can be appropriately handled with one vacuum gauge without causing inconvenience such as oil or oil vapor from the oil rotary vacuum pump flowing into the vacuum vessel. The inside can leak to atmospheric pressure.

Further, in the vacuum exhaust system of the present onset Ming is branched formed between the pair of on-off valves, a configuration provided with the leak portion having the leak valve for leaks between the pair of on-off valves to atmospheric pressure by opening It is preferable.
According to the present invention, a leak portion including a leak valve that leaks to atmospheric pressure between the pair of on-off valves by opening is formed between the pair of on-off valves.
As a result, when returning the inside of the vacuum vessel from the vacuum state to the atmospheric pressure state, the leakage valve is opened after opening one on-off valve, so that the gap between the vacuum vessel side and the other on-off valve is reduced. It becomes an atmospheric pressure state. After that, when the other opening / closing valve is opened, the air on the vacuum vessel side in the atmospheric pressure state flows into the oil rotary vacuum pump side. Therefore, the oil rotary vacuum pump may be stopped thereafter. For this reason, it is possible to prevent air on the oil rotary vacuum pump side containing harmful oil and oil vapor from flowing into the vacuum vessel and the vacuum gauge through the other opening / closing valve. Therefore, the inside of the vacuum vessel can be satisfactorily returned to the atmospheric pressure state by an easy process with a simple configuration.

Further, a vacuum exhaust system of the present onset Ming, the control means, the leak valve to Hirakijo on purpose the second on-off valve connected to the oil-rotary vacuum pump after the closed state, the vacuum container side the one of the opening and closing valve for connecting and Hirakijo on purpose, when the vacuum degree of the vacuum container measured by the vacuum gauge recognizes that almost atmospheric pressure, the second on-off valve and Hirakijo on purpose It is preferable that the oil rotary vacuum pump be controlled so as to control a leak process.
In the present invention, as the leakage control by the control means, the leakage valve can be opened after the other opening / closing valve is closed. For example, the leakage valve is manually opened or the leakage valve is automatically opened by the control means. And so on. Further, the control means can open one of the open / close valves, for example, performs a manual opening process or an automatic opening process by the control means. Then, the control unit recognizes that the vacuum degree of the vacuum container measured by the vacuum gauge had to about atmospheric pressure, to leak the oil-rotary vacuum pump to the atmospheric pressure and the other of the opening and closing valve is opened condition.
As a result, even when the inside of the vacuum vessel is leaked to atmospheric pressure, the vacuum vessel can be appropriately handled with one vacuum gauge without causing inconvenience such as oil or oil vapor from the oil rotary vacuum pump flowing into the vacuum vessel. The inside can leak to atmospheric pressure.

The method of evacuating the onset Ming, a vacuum evacuation method for evacuating a vacuum container in vacuum, the oil-rotary vacuum pump for evacuating the vacuum vessel to a vacuum through a pair of opening and closing valves connected in series form When, using a vacuum gauge for measuring the vacuum degree which is provided positioned between the pair of on-off valves, when the oil-rotary vacuum pump is driven, hand-off valve that connects to the vacuum container side A vacuum container vacuum degree storage step for storing container vacuum degree data relating to the degree of vacuum measured by the vacuum gauge in an open state for a predetermined period, and after the vacuum vessel vacuum degree storage step, the one on-off valve is closed. oil-rotary vacuum pump to obtain the pump vacuum-degree data about the vacuum degree of the oil-rotary vacuum pump to the opening and closing valve other hand to connect to the oil-rotary vacuum pump measured by the vacuum gauge as opened after And sky degree obtaining step, after the oil-rotary vacuum pump vacuum obtaining step, comparing the pump vacuum-degree data about the vacuum degree of the oil-rotary vacuum pump for measuring the storage containers vacuum-degree data by the vacuum gauge When it is recognized that the degree of vacuum of the pump vacuum degree data relating to the degree of vacuum on the oil rotary vacuum pump side is a degree of vacuum greater than the degree of vacuum in the stored vacuum vessel, And an evacuation step of evacuating the inside of the vacuum vessel by the oil rotary vacuum pump that is driven with the open / close valve open.
In the present invention, when the oil rotary vacuum pump is driven, the vacuum container vacuum degree storing step is performed. That is, the degree of vacuum measured by a vacuum gauge with one open / close valve connected to the vacuum vessel side opened in a predetermined period and the other open / close valve connected to the oil rotary pump side closed during the same period is measured in the vacuum vessel. Acquired and stored as container vacuum data regarding the vacuum. After this vacuum container vacuum degree storage step, an oil rotary vacuum pump vacuum degree acquisition step is performed. That is, after closing one open / close valve, open the other open / close valve connected to the oil rotary vacuum pump side and open the other open / close valve to determine the degree of vacuum measured by the vacuum gauge as the pump vacuum degree related to the vacuum degree on the oil rotary vacuum pump side. Get as data. After this oil rotary vacuum pump vacuum degree acquisition step, a vacuum exhaust step is performed. That is, a pair of on-off valves are opened, and the vacuum container is evacuated to vacuum by a driving oil rotary vacuum pump.
As a result, the inside of the vacuum vessel can be properly evacuated with a single vacuum gauge without causing inconvenience such as oil or oil vapor from the oil rotary vacuum pump flowing into the vacuum vessel. Can be simplified.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In the present embodiment, the vacuum evacuation device of the present invention is exemplified by a configuration applied to, for example, an optical interferometer, but can be applied to a configuration including various vacuum vessels that are evacuated to vacuum.
FIG. 1 is a block diagram showing a schematic configuration of a vacuum exhaust apparatus in the present embodiment.

[Configuration of vacuum exhaust system]
In FIG. 1, reference numeral 100 denotes a vacuum evacuation device. This vacuum evacuation device 100 is used for an optical interferometer (not shown), for example, and serves as a vacuum container as a vacuum container constituting a laser beam interference portion of the optical interferometer. This is an apparatus for evacuating the chamber 101 to a vacuum.
The vacuum exhaust apparatus 100 includes an oil rotary vacuum pump 110, an exhaust pipe 120, a leak pipe 130 as a leak portion, a vacuum gauge 140, and a control means (not shown).

The oil rotary vacuum pump 110 is connected to the vacuum chamber 101 via the exhaust pipe 120. The oil rotary vacuum pump 110 is evacuated from the vacuum chamber 101 through the exhaust pipe 120 by driving, and the vacuum chamber 101 is evacuated.
The oil rotary vacuum pump 110 can be driven manually, for example, by a power switch to be activated by power supplied from a power supply unit (not shown), or driven by control means that recognizes the switch operation. Any driving method can be used, such as automatic.

For example, a pressure-resistant pipe is used as the exhaust pipe 120, and one end side is connected to the vacuum chamber 101 and the other end side is connected to the oil rotary vacuum pump 110. The exhaust pipe 120 is provided with a first on-off valve 121 that is a pair of on-off valves in series and a second on-off valve 122 that is the other on-off valve. The first opening / closing valve 121 and the second opening / closing valve 122 include an opening / closing valve located on the vacuum chamber 101 side as the first opening / closing valve 121, and an opening / closing valve located on the oil rotary vacuum pump 110 side as the second opening / closing valve 122. To do.
The first opening / closing valve 121 and the second opening / closing valve 122 are, for example, electromagnetic opening / closing types that are opened / closed by the control means, can be opened / closed by the control means, and automatically when the power supply to the control means is interrupted. A so-called normal close valve that is automatically closed can be used.

The leak pipe 130 serving as a leak portion is, for example, a pressure-resistant pipe, as in the exhaust pipe 120, and is connected to a state where one end side branches between the vacuum chamber 101 and the second opening / closing valve 122 in the exhaust pipe 120, The other end is a free end that opens to the atmosphere.
The leak pipe 130 is provided with a leak valve 131. By opening the leak valve 131, that is, in an open state, a leak between the vacuum chamber 101 and the second opening / closing valve 122 in the exhaust pipe 120 is caused to atmospheric pressure.

As the vacuum gauge 140, for example, various vacuum gauges capable of measuring a degree of vacuum that does not cause an adverse effect due to air refraction of laser light in an optical interferometer, such as an ionization vacuum gauge or a Pirani vacuum gauge, can be used.
The vacuum gauge 140 is disposed between the first opening / closing valve 121 and the second opening / closing valve 122 in the exhaust pipe 120, and measures the degree of vacuum at this position. The vacuum gauge 140 is connected to the control means, and outputs data corresponding to the measured degree of vacuum to the control means.

The control means includes, for example, a CPU (Central Processing Unit), and the first opening and closing based on the degree of vacuum measured by the vacuum gauge 140 such as evacuating the vacuum chamber 101 or leaking to the atmospheric pressure in the vacuum chamber 101. The opening and closing of the valve 121 and the second opening / closing valve 122 is controlled.
Specifically, the control means performs vacuum evacuation processing, vacuum re-evacuation processing, leak processing, and the like. The control means acquires vacuum degree data related to the degree of vacuum measured by the vacuum gauge 140 based on a reference pulse such as an internal clock. That is, when the vacuum degree data relating to the vacuum degree measured and output by the vacuum gauge 140 is input, the control means stores it in a cache memory or the like for appropriate calculation.

In the vacuum evacuation process, the control means recognizing the signal requesting the vacuum evacuation process in the vacuum chamber 101 communicates through the exhaust pipe 120 with the first opening / closing valve 121 open. The vacuum degree data output by measuring the vacuum degree by the vacuum gauge 140 is acquired as container vacuum degree data and stored in storage means such as a RAM (Random Access Memory). Thereafter, the first opening / closing valve 121 is closed, the second opening / closing valve 122 is opened, and the degree of vacuum on the oil rotary vacuum pump 110 side communicating through the exhaust pipe 120 is measured by the vacuum gauge 140 and output. Vacuum degree data is acquired as pump vacuum degree data. Examples of the signal requesting the vacuum exhausting process include recognition of a control signal from the control device and recognition of activation of the oil rotary vacuum pump 110, which will be described later.
Then, the control means opens the first on-off valve 121 and the second on-off valve 122, communicates the vacuum chamber 101 and the oil rotary vacuum pump 110 via the exhaust pipe 120, and drives the oil rotary vacuum pump 110 to drive. The inside of the vacuum chamber 101 is evacuated to a vacuum. When the control means recognizes that the degree of vacuum in the vacuum chamber 101, which is sequentially measured by the vacuum gauge 140, has reached a predetermined degree of vacuum, it stops driving the oil rotary vacuum pump 110. In addition, the second open / close valve 122 is closed so that the degree of vacuum in the vacuum chamber 101 can be maintained while being monitored by the vacuum gauge 140, and the processing is ended.

Further, in the vacuum re-evacuation process, the degree of vacuum in the vacuum chamber 101 is lowered, the oil rotary vacuum pump 110 that is stopped is driven, and the control means requests the vacuum re-evacuation in the vacuum chamber 101. When a signal requesting re-exhaust processing is recognized, it is recognized that the first opening / closing valve 121 is open and the second opening / closing valve 122 is closed, and the vacuum in the vacuum chamber 101 communicating with the exhaust pipe 120 is recognized. The degree is measured by the vacuum gauge 140 and stored. When the control unit recognizes that the first on-off valve 121 is open and the second on-off valve 122 is not closed, the control unit switches the first on-off valve 121 to the open state and the second on-off valve 122 to the closed state.
And after memorizing the vacuum degree of the vacuum chamber 101, the first on-off valve 121 is closed, then the second on-off valve 122 is opened, and the vacuum degree on the oil rotary vacuum pump 110 side is sequentially measured by the vacuum gauge 140, The stored degree of vacuum in the vacuum chamber 101 is compared with the degree of vacuum on the oil rotary vacuum pump 110 side that is sequentially measured. Then, the control means confirms that the degree of vacuum on the oil rotary vacuum pump 110 side that is sequentially measured by the vacuum gauge 140 is higher than the degree of vacuum stored in the vacuum chamber 101 stored in advance. When recognized, the first opening / closing valve 121 is opened. By setting the first open / close valve 121 in the open state, the first open / close valve 121 and the second open / close valve 122 are opened, and the oil rotary vacuum pump 110 that drives the vacuum chamber 101 and the oil rotary vacuum pump 110 to communicate with each other. The vacuum chamber 101 is again evacuated to a vacuum.

Further, in the leak process, the leak valve 131 can be opened after the second opening / closing valve 122 is closed, for example, a manual opening process of the leak valve 131 or an automatic opening process of the leak valve 131 by the control means is performed. To do.
Further, when the control means recognizes that the degree of vacuum in the vacuum chamber 101 measured by the vacuum gauge 140 has become almost atmospheric pressure, the control means opens the second opening / closing valve 122. By setting the second open / close valve 122 in the open state, the oil rotary vacuum pump 110 side leaks to atmospheric pressure.
The control means can stop the driving of the oil rotary vacuum pump 110, for example, the control for automatically stopping the driving as described above, or the control for enabling the supply power to be cut off according to the manual stopping operation.
That is, by first opening the second opening / closing valve 122 and stopping the oil rotary vacuum pump 110, it is possible to reliably prevent contamination with air containing oil or oil vapor.

  Further, for example, a control device such as a personal computer for setting / controlling the operation of the entire optical interferometer is connected to the control means. Then, when the control means recognizes various control signals based on various setting signals in accordance with an input operation such as a keyboard that can be input in the control device by a user of the optical interferometer as an operator, the optical interferometer Control the whole operation.

[Operation of vacuum exhaust system]
Next, the operation of the vacuum exhaust apparatus 100 will be described with reference to the drawings.

(Evacuation process)
Hereinafter, as the operation of the vacuum exhaust apparatus 100, the operation of the vacuum exhaust process will be described with reference to the drawings.
In the present embodiment, the oil rotary vacuum pump 110 is illustrated as being configured to be driven and stopped by a manual operation by a user. However, for example, the control means automatically performs an oil operation by an input operation requesting a vacuum exhaust process. The rotary vacuum pump 110 may be driven or stopped.
2A and 2B are timing charts showing operations in the evacuation process. FIG. 2A is a graph showing the vacuum pressure Pvc in the vacuum chamber 101, FIG. 2B is a graph showing the vacuum pressure Pvp in the oil rotary vacuum pump 110, and FIG. ) Is a waveform diagram showing a trigger signal, (D) is a waveform diagram showing opening and closing of the first on-off valve 121, (E) is a waveform diagram showing opening and closing of the second on-off valve 122, and (F) is measured by the vacuum gauge 140. It is a wave form diagram which shows the timing which reads the vacuum degree to do.

First, for example, a user using an optical interferometer turns on the oil rotary vacuum pump 110 to drive it, and in order to evacuate the vacuum chamber 101 in the optical interferometer, When the control means performs an input operation for requesting, as shown in FIG. 2C, a control signal related to the request for the vacuum evacuation process is output from the control means.
The control means that recognizes this control signal opens the first on-off valve 121 in a predetermined period as shown in FIG. When setting the open state of the first open / close valve 121, it is determined whether or not the second open / close valve 122 and the leak valve 131 are closed. The valve 131 is closed. Further, the closed state of the leak valve 131 is automatically controlled to be switched to the closed state by the control means, or the user recognizes that the leak valve 131 has been switched based on a notification for manually switching to the closed state. Either automatic or manual methods may be used. In the case of manual operation, it is preferable to shift to the evacuation process only when it is recognized that the leak valve 131 has been switched to the closed state. The exhaust pipe 120 is in communication with the vacuum chamber 101 due to the open state of the first opening / closing valve 121.

Further, after the control for switching the first opening / closing valve 121 to the open state, the control means performs a trigger signal for performing an operation of acquiring data relating to the degree of vacuum measured by the vacuum gauge 140 as shown in FIG. Start oscillation of the reference pulse. When the reference pulse is oscillated with the first opening / closing valve 121 open, the control means acquires vacuum degree data relating to the degree of vacuum measured by the vacuum gauge 140, that is, the vacuum of the exhaust pipe 120 communicating with the vacuum chamber 101. The container vacuum degree data obtained by measuring the degree of vacuum Pvc, which is the pressure, is acquired and stored in a storage means (not shown), and the vacuum container vacuum degree storing step is performed (see FIG. 2A).
After the vacuum container vacuum degree storing step, the control means opens the second opening / closing valve 122 in a predetermined time after the first opening / closing valve 121 is closed, as shown in FIG. The exhaust pipe 120 is in communication with the oil rotary vacuum pump 110 by the open state of the second opening / closing valve 122. In this state, when the reference pulse is oscillated, the control means obtains vacuum degree data relating to the degree of vacuum measured by the vacuum gauge 140, that is, a vacuum that is the vacuum pressure of the exhaust pipe 120 communicating with the oil rotary vacuum pump 110. A pump vacuum degree data obtained by measuring the degree of pressure Pvp is obtained, and an oil rotary vacuum pump vacuum degree acquisition step of storing in the storage means is performed (see FIG. 2B).

After this oil rotary vacuum pump vacuum degree acquisition step, the control means compares the container vacuum degree data stored in the vacuum vessel vacuum degree storage step with the pump vacuum degree data stored in the oil rotary vacuum pump vacuum degree acquisition step. Then, when recognizing that the degree of vacuum in the pump vacuum degree data relating to the degree of vacuum on the oil rotary vacuum pump 110 side is higher than the degree of vacuum in the vacuum chamber 101, the first opening / closing valve 121 is recognized. Is opened. In addition, as a process after this oil rotary vacuum pump vacuum degree acquisition step, for example, in order to check the degree of vacuum by measurement of the vacuum gauge 140, for example, after the second on-off valve 122 is once closed, The valve 121 and the second opening / closing valve 122 may be opened.
With the first open / close valve 121 and the second open / close valve 122 open, the oil rotary vacuum pump 110 and the vacuum chamber 101 communicate with each other via the exhaust pipe 120. Then, the inside of the vacuum chamber 101 is evacuated to vacuum by the driven oil rotary vacuum pump 110. At the time of this evacuation, the control means acquires vacuum data from the vacuum gauge 140 for each reference pulse, and determines whether or not a predetermined degree of vacuum Pm, for example, 0.1 Pa has been reached. When it is recognized that the inside of the vacuum chamber 101 has reached the degree of vacuum Pm that is a preset target threshold (see FIGS. 2A and 2B), measurement and observation using the vacuum chamber 101 are performed. Can be implemented.
If it is recognized that the target degree of vacuum Pm has been reached, the second opening / closing valve 122 may be closed to stop the oil rotary vacuum pump 110, and the vacuum exhaust process may be completed. According to this configuration, unnecessary power supply to the oil rotary vacuum pump 110 can be prevented, and energy saving can be easily obtained. In this evacuation process, the second opening / closing valve 122 is closed after the inside of the vacuum chamber 101 reaches the target degree of vacuum Pm, but the second opening / closing valve 122 may not be closed.

(Vacuum re-evacuation process)
Next, the operation of the vacuum re-evacuation process as the operation of the vacuum exhaust apparatus 100 will be described with reference to the drawings.
In this vacuum re-evacuation process, the degree of vacuum in the vacuum chamber 101 is lowered and stopped in a state where the drive of the oil rotary vacuum pump 110 is stopped after the vacuum chamber 101 is evacuated. A process of driving the oil rotary vacuum pump 110 and evacuating again will be exemplified. Further, as described above, the oil rotary vacuum pump 110 is exemplified by a configuration that is driven and stopped by a manual operation by a user. However, for example, the control unit automatically performs an oil operation by an input operation for requesting an evacuation process. The rotary vacuum pump 110 may be driven or stopped.
3A and 3B are timing charts showing operations in the vacuum re-evacuation process, where FIG. 3A is a graph showing the vacuum pressure Pvc in the vacuum chamber 101, FIG. 3B is a graph showing the vacuum pressure Pvp in the oil rotary vacuum pump 110, (C) is a waveform diagram showing a trigger signal, (D) is a waveform diagram showing opening and closing of the first on-off valve 121, (E) is a waveform diagram showing opening and closing of the second on-off valve 122, and (F) is a vacuum gauge 140. It is a wave form diagram which shows the timing which reads the vacuum degree to measure.

First, for example, a user who uses an optical interferometer turns on and drives the oil rotary vacuum pump 110 and performs vacuum re-evacuation in order to perform vacuum re-evacuation in the vacuum chamber of the optical interferometer. By performing the input operation for requesting the processing by the control means, as shown in FIG. 3C, a control signal related to the request for the vacuum re-evacuation processing is output from the control means. The control means that recognizes this control signal recognizes that the first on-off valve 121 is in the open state and the second on-off valve 122 is in the closed state, and as shown in FIGS. Corresponding to the pulse, vacuum degree data relating to the vacuum degree measured by the vacuum gauge 140 is obtained, that is, the container vacuum degree data obtained by measuring the vacuum degree Pvc of the exhaust pipe 120 communicating with the vacuum chamber 101 is obtained. Do not store in storage means. Here, when the first on-off valve 121 is in the open state and the second on-off valve 122 is not in the closed state, the control means opens the first on-off valve 121 and closes the second on-off valve 122. .
After the degree of vacuum in the vacuum chamber 101 is stored, the first opening / closing valve 121 is closed (see FIG. 3D) and then the second opening / closing valve 122 is opened (see FIG. 3E). In this state, the control means obtains vacuum degree data relating to the degree of vacuum measured by the vacuum gauge 140 corresponding to the reference pulse, that is, obtained by measuring the degree of vacuum Pvp of the exhaust pipe 120 communicating with the oil rotary vacuum pump 110. The obtained pump vacuum data is sequentially acquired. Further, the control unit compares the vacuum degree Pvp of the oil rotary vacuum pump 110 acquired sequentially with the vacuum degree Pvc of the vacuum chamber 101 acquired and stored previously. Then, the control means has the degree of vacuum Pvp on the oil rotary vacuum pump 110 side, which is sequentially measured by the vacuum gauge 140, having a degree of vacuum greater than the degree of vacuum Pvc in the vacuum chamber 101 stored in advance. When this is recognized, the first opening / closing valve 121 is opened.
When controlling the open state of the first on-off valve 121, as described above, for example, the second on-off valve 122 is once closed, then the first on-off valve 121 is opened, and the second on-off valve 122 is again opened. May be open.
When the first on-off valve 121 and the second on-off valve 122 are opened, the vacuum chamber 101 and the oil rotary vacuum pump 110 communicate with each other, and the inside of the vacuum chamber 101 is evacuated to a vacuum by the driven oil rotary vacuum pump 110. Thereafter, the same processing as the evacuation processing shown in FIG. 2 is performed.

(Oil rotary vacuum pump stop process for calibration work)
Next, as an operation of the vacuum exhaust apparatus 100, an operation of a process for stopping the oil rotary vacuum pump 110 for calibration work or the like will be described with reference to the drawings.
In addition, since it is necessary to hold | maintain a vacuum state between the vacuum chamber 101 and the 2nd opening-and-closing valve 122, in order to maintain a more reliable vacuum state, the leak valve 131 is kept closed. Moreover, the oil rotary vacuum pump 110 is not limited to stop driving for calibration, but the oil rotary vacuum pump 110 may be used for the purpose of reducing the operation cost, for example, after the above-described vacuum exhausting process or vacuum re-exhausting process. The same applies when stopping.
4A and 4B are timing charts showing the operation in the stop process of the oil rotary vacuum pump 110. FIG. 4A is a graph showing the vacuum pressure Pvc in the vacuum chamber 101, and FIG. 4B shows the vacuum pressure Pvp in the oil rotary vacuum pump 110. (C) is a waveform diagram showing a trigger signal, (D) is a waveform diagram showing opening and closing of the first on-off valve 121, (E) is a waveform diagram showing opening and closing of the second on-off valve 122, and (F) is FIG. 4G is a waveform diagram showing timing for reading the degree of vacuum measured by the vacuum gauge 140, and FIG.

First, for example, a user using an optical interferometer performs an input operation for requesting a stop process of the oil rotary vacuum pump 110 in order to perform calibration of the optical interferometer by the control means. As shown in FIG. 4C, a control signal related to a request for stop processing of the oil rotary vacuum pump 110 is output from the control means. The control means that recognizes this control signal closes the second opening / closing valve 122 as shown in FIG. As a result, the exhaust pipe 120 connected to the vacuum gauge 140 is in a state of communicating only with the vacuum chamber 101. In this state, in response to the reference pulse, the control means obtains vacuum degree data relating to the degree of vacuum measured by the vacuum gauge 140, and continues to monitor the vacuum degree Pvc of the vacuum chamber 101.
Thereafter, the control means performs processing capable of stopping the oil rotary vacuum pump 110. Specifically, the user is notified by a display or audio output that permits the oil rotary vacuum pump 110 to stop, or the power supply of the oil rotary vacuum pump 110 is automatically shut off. And by stopping the drive of the oil rotary vacuum pump 110, as shown in FIG. 4B, the oil rotary vacuum pump 110 side gradually becomes closer to the atmospheric pressure.

(Leak processing)
Next, as an operation of the vacuum exhaust apparatus 100, an operation of a leak process will be described with reference to the drawings.
In this leak process, the process of leaking the inside of the vacuum chamber 101 to the atmospheric pressure from the state in which the oil rotary vacuum pump 110 that is driven with the first open / close valve 121 and the second open / close valve 122 open is illustrated. . Further, as described above, the oil rotary vacuum pump 110 is exemplified by a configuration that is driven and stopped by a manual operation by a user. However, for example, the control unit automatically performs an oil operation by an input operation for requesting an evacuation process. The rotary vacuum pump 110 may be driven or stopped.
5A and 5B are timing charts showing the operation in the leak process, where FIG. 5A is a graph showing the vacuum pressure Pvc in the vacuum chamber 101, FIG. 5B is a graph showing the vacuum pressure Pvp in the oil rotary vacuum pump 110, and FIG. Is a waveform diagram showing the trigger signal, (D) is a waveform diagram showing opening and closing of the first on-off valve 121, (E) is a waveform diagram showing opening and closing of the second on-off valve 122, and (F) is measured by the vacuum gauge 140. FIG. 5G is a waveform diagram showing timing for reading the degree of vacuum, FIG. 5G is a waveform diagram showing opening and closing of the leak valve 131, and FIG. 5H is a waveform diagram showing a trigger signal for opening and closing the leak valve 131.

First, for example, when the user stops using the optical interferometer and does not use the optical interferometer for a relatively long time, an input indicating that a leak process is required to make the inside of the vacuum chamber 101 in the optical interference into an atmospheric pressure. By performing the operation by the control means, as shown in FIG. 5C, a control signal related to a request for leak processing is output from the control means. The control means that has recognized this control signal closes the second opening / closing valve 122 as shown in FIG. Then, as shown in FIGS. 5G and 5H, the control means performs a process for enabling the leak valve 131 to be opened. Specifically, the user is notified by a display or audio output that permits the user to switch the leak valve 131 to the open state, or the leak valve 131 is automatically switched to the open state. Then, by switching the leak valve 131 to the open state, the vacuum chamber 101 communicates with the atmosphere and becomes atmospheric pressure as shown in FIG.
Thereafter, when the control means recognizes that the inside of the vacuum chamber 101 has become almost atmospheric pressure based on the container vacuum degree data measured by the vacuum gauge 140, as shown in FIG. While opening the valve 122, the oscillation of the reference pulse is stopped and the monitoring of the degree of vacuum is stopped. As a result, as shown in FIG. 5B, the oil rotary vacuum pump 110 communicates with the atmosphere, but since it is driven by vacuum suction, a reduced pressure state close to atmospheric pressure is maintained. Further, the control means performs processing capable of stopping the oil rotary vacuum pump 110. Specifically, the user is notified by a display or audio output that permits the oil rotary vacuum pump 110 to stop, or the power supply of the oil rotary vacuum pump 110 is automatically shut off. Then, by stopping the operation of the oil rotary vacuum pump 110, as shown in FIG. 5B, the oil rotary vacuum pump 110 side gradually becomes closer to the atmospheric pressure and becomes atmospheric pressure. With the above procedure, the processing for setting the inside of the vacuum chamber 101 to atmospheric pressure in optical interference is completed.

[Effects of Embodiment]
As described above, in the above-described embodiment, a pair of the first on-off valve 121 and the second on-off valve are connected in series between the vacuum chamber 101 and the oil rotary vacuum pump 110 that exhausts the vacuum chamber 101 to a vacuum. 122, and a vacuum gauge 140 for measuring the degree of vacuum is provided between the first opening / closing valve 121 and the second opening / closing valve 122. Then, the degree of vacuum Pvc in the vacuum chamber 101 can be measured by opening the first opening / closing valve 121 connected to the vacuum chamber 101 side, and the second opening / closing valve 122 connected to the oil rotary vacuum pump 110 side is opened. It is possible to measure the degree of vacuum Pvp on the oil rotary vacuum pump 110 side, and measure the degree of vacuum while evacuating the inside of the vacuum chamber 101 by the oil rotary vacuum pump 110 that is driven by opening both of them. it can.
Therefore, even with a single vacuum gauge 140, an appropriate degree of vacuum can be measured while preventing the inconvenience of oil or oil vapor from the oil rotary vacuum pump 110 from flowing into the vacuum chamber 101, and the configuration can be simplified. Thus, improvement in manufacturability and reduction in apparatus cost can be easily obtained.

In the embodiment, the control means controls the opening / closing of the pair of first opening / closing valves 121 and the second opening / closing valve 122 based on the degree of vacuum measured by the vacuum gauge 140.
For this reason, the vacuum chamber 101 and the oil rotary vacuum pump 110 communicate with each other in a state where the degree of vacuum is higher on the vacuum chamber 101 side than on the oil rotary vacuum pump 110 side due to an erroneous operation by a user of the optical interferometer. It is possible to prevent the occurrence of inconvenience such as the oil or oil vapor from the oil rotary vacuum pump 110 flowing into the vacuum chamber 101. Furthermore, since the first on-off valve 121 and the second on-off valve 122 are automatically opened and closed, the workability of exhausting to a vacuum can be improved.

Further, in the above embodiment, when the oil rotary vacuum pump 110 is driven by the control means, the evacuation process is controlled. That is, the control means opens the first opening / closing valve 121 connected to the vacuum chamber 101 side, stores the degree of vacuum in the vacuum chamber 101 measured by the vacuum gauge 140, closes the first opening / closing valve 121, The second opening / closing valve 122 connected to the rotary vacuum pump 110 side is opened, and the degree of vacuum on the oil rotary vacuum pump 110 side measured by the vacuum gauge 140 is acquired. Thereafter, the control means compares the stored degree of vacuum Pvc in the vacuum chamber 101 with the degree of vacuum Pvp on the oil rotary vacuum pump 110 side measured by the vacuum gauge 140. When recognizing that the degree of vacuum Pvp on the oil rotary vacuum pump 110 side measured by the vacuum gauge 140 is higher than the stored degree of vacuum Pvc in the vacuum chamber 101, a pair of first vacuum The open / close valve 121 and the second open / close valve 122 are opened, and the vacuum rotary chamber 110 is driven to evacuate the vacuum chamber 101 to a vacuum.
For this reason, the inside of the vacuum chamber 101 can be appropriately evacuated by the single vacuum gauge 140 without causing inconvenience such as oil or oil vapor from the oil rotary vacuum pump 110 flowing into the vacuum chamber 101.

Further, in the above embodiment, after the degree of vacuum on the oil rotary vacuum pump 110 side is acquired by the control means, the pair of first on-off valve 121 and second on-off valve 122 are opened to evacuate the vacuum chamber 101 to vacuum. When it is recognized that the degree of vacuum Pvc in the vacuum chamber 101 measured by the vacuum gauge 140 has reached a predetermined degree of vacuum Pm, the second opening / closing valve 122 is closed.
For this reason, even if the drive of the oil rotary vacuum pump 110 is stopped, there is no inconvenience such as oil or oil vapor from the oil rotary vacuum pump 110 flowing into the vacuum chamber 101, and the vacuum state by the vacuum gauge 140 is reduced. The maintenance of the vacuum state in the vacuum chamber 101 can be prolonged while monitoring. Further, the operation cost for maintaining the vacuum chamber 101 in a vacuum state can be reduced by stopping the driving of the oil rotary vacuum pump 110. Furthermore, for example, during calibration in a precision instrument such as an optical interferometer using the vacuum chamber 101, the calibration operation becomes complicated due to vibration caused by driving of the oil rotary vacuum pump 110, or the calibration accuracy decreases. Such inconveniences can be prevented by stopping the operation of the oil rotary vacuum pump 110.

Further, in the above embodiment, the control means controls the first opening / closing valve 121 to be opened and the second opening / closing valve 122 to be closed after the degree of vacuum Pvc in the vacuum chamber 101 reaches a predetermined degree of vacuum Pm. Thereafter, the drive of the oil rotary vacuum pump 110 can be stopped, for example, a control for automatically stopping the drive or a control for enabling the supply power to be cut off in accordance with a manual stop operation, a notification process for prompting the stop by guidance, and the like.
For this reason, there is a problem that oil, oil vapor, etc. from the oil rotary vacuum pump 110 flows into the vacuum chamber 101 due to the stop of the oil rotary vacuum pump 110 in a state where the vacuum chamber 101 and the oil rotary vacuum pump 110 communicate with each other. It can be surely prevented.

Further, in the above embodiment, when the oil rotary vacuum pump 110 that is stopped when the degree of vacuum Pvc in the vacuum chamber 101 exceeds the predetermined degree of vacuum Pm is driven, a vacuum re-evacuation process is performed by the control means. To control. That is, the control means stores the degree of vacuum Pvc in the vacuum chamber 101 measured by the vacuum gauge 140 when the first opening / closing valve 121 is open and the second opening / closing valve 122 is closed, and then closes the first opening / closing valve 121. After that, the second opening / closing valve 122 is opened, and the vacuum degree Pvp on the oil rotary vacuum pump 110 side is sequentially measured by the vacuum gauge 140, and the stored vacuum degree Pvc in the vacuum chamber 101 and the oil rotary vacuum pump for sequentially measuring The degree of vacuum Pvp on the 110 side is compared. Then, the control means has the degree of vacuum Pvp on the oil rotary vacuum pump 110 side, which is sequentially measured by the vacuum gauge 140, having a degree of vacuum greater than the degree of vacuum Pvc in the vacuum chamber 101 stored in advance. When the first on-off valve 121 is opened and the pair of the first on-off valve 121 and the second on-off valve 122 are in the open state, the oil rotary vacuum pump 110 to drive the inside of the vacuum chamber 101. Re-evacuate to vacuum.
For this reason, even in the case of re-evacuation, the vacuum chamber 101 is appropriately evacuated by one vacuum gauge 140 without causing inconvenience such as oil or oil vapor from the oil rotary vacuum pump 110 flowing into the vacuum chamber 101. Can be exhausted.

Moreover, in the said embodiment, between the vacuum chamber 101 and the 1st on-off valve 121 connected to this vacuum chamber 101 side, the inside of the exhaust pipe 120 between the vacuum chamber 101 and the 1st on-off valve 121 is made atmospheric pressure by opening. A leak pipe 130 having a leak valve 131 for leaking is branched.
As a result, when the vacuum chamber 101 is returned from the vacuum state to the atmospheric pressure state, the second on-off valve 122 is closed and the first on-off valve 121 is opened, and then the leak valve is opened. There is an atmospheric pressure state between the chamber 101 side and the second opening / closing valve 122. After that, when the second opening / closing valve 122 is opened, air on the vacuum chamber 101 side that is in the atmospheric pressure state flows into the oil rotary vacuum pump 110 side. Therefore, the oil rotary vacuum pump 110 may be stopped thereafter. . For this reason, it is possible to prevent air on the oil rotary vacuum pump 110 side containing harmful oil and oil vapor from flowing into the vacuum chamber 101 and the vacuum gauge 140 through the second opening / closing valve 122. Therefore, even when the vacuum pressure portion is opened to the atmospheric pressure for maintenance, for example, the inside of the vacuum chamber 101 can be satisfactorily returned to the atmospheric pressure state with a simple configuration and easy processing.

Furthermore, in the above-described embodiment, the leakage valve 131 can be opened after the second opening / closing valve 122 is closed as the leakage control by the control means. For example, the leakage valve 131 can be opened manually or the leakage valve by the control means. The automatic release processing 131 is performed. Further, when the control means recognizes that the degree of vacuum Pvc in the vacuum chamber 101 measured by the vacuum gauge 140 has become almost atmospheric pressure, the second opening / closing valve 122 is opened to bring the oil rotary vacuum pump 110 side to atmospheric pressure. To leak. The control means can stop driving of the oil rotary vacuum pump 110, for example, a control to automatically stop driving, a control to perform a notification process that can cut off the supplied power according to a manual stop operation, or to prompt a manual stop, etc. To do.
For this reason, even when the inside of the vacuum chamber 101 is leaked to the atmospheric pressure, one vacuum gauge 140 is suitable without causing inconvenience such as oil or oil vapor from the oil rotary vacuum pump 110 flowing into the vacuum chamber 101. In addition, the inside of the vacuum chamber 101 can be leaked to atmospheric pressure.

[Modification of Embodiment]
The embodiment described above shows one embodiment of the present invention, and the present invention is not limited to the above-described embodiment, and within the scope of achieving the objects and effects of the present invention. Needless to say, these changes and improvements are included in the content of the present invention. In addition, the specific structure and shape in carrying out the present invention may be used as other structures and shapes within the scope of achieving the object and effect of the present invention.

  That is, the vacuum evacuation device of the present invention has been exemplified by the configuration in which the vacuum chamber 101 in the optical interferometer is evacuated as a vacuum vessel, but can be applied to a configuration in which various vacuum vessels such as an electron microscope are evacuated to vacuum. .

Further, the leak pipe 130 having the leak valve 131 is branched from the exhaust pipe 120 between the vacuum chamber 101 and the first open / close valve 121. For example, as shown in FIG. A branch may be formed between the opening and closing valves 122.
In the embodiment shown in FIG. 6, when leak processing is performed, the first on-off valve 121 is opened to bring the vacuum chamber 101 to atmospheric pressure, and then the second on-off valve 122 is opened to set the oil rotary vacuum pump 110. The oil rotary vacuum pump 110 is stopped by processing the side to atmospheric pressure. This prevents inconvenience that oil from the oil rotary vacuum pump 110 flows into the vacuum chamber 101.

  In addition, the specific structure and shape in the implementation of the present invention may be other structures as long as the object of the present invention can be achieved.

It is a block diagram which shows schematic structure of the vacuum exhaust apparatus in one Embodiment which concerns on this invention. FIG. 4 is a timing chart showing an operation in the vacuum evacuation process in the embodiment, where (A) is a graph showing the vacuum pressure Pvc in the vacuum chamber, (B) is a graph showing the vacuum pressure Pvp in the oil rotary vacuum pump, and (C) is a graph. Waveform diagram showing trigger signal, (D) is a waveform diagram showing opening and closing of the first on-off valve, (E) is a waveform diagram showing opening and closing of the second on-off valve, and (F) reads the degree of vacuum measured by a vacuum gauge. It is a wave form diagram which shows a timing. FIG. 5 is a timing chart showing the operation in the vacuum re-evacuation process in the embodiment, where (A) is a graph showing the vacuum pressure Pvc in the vacuum chamber, (B) is a graph showing the vacuum pressure Pvp in the oil rotary vacuum pump, and (C). Is a waveform diagram showing the trigger signal, (D) is a waveform diagram showing the opening and closing of the first on-off valve, (E) is a waveform diagram showing the opening and closing of the second on-off valve, and (F) is the degree of vacuum measured by a vacuum gauge. It is a wave form diagram which shows the timing which reads. It is a timing chart which shows the operation | movement in the stop process of the oil rotary vacuum pump in the said embodiment, (A) is a graph which shows the vacuum pressure Pvc in a vacuum chamber, (B) is a graph which shows the vacuum pressure Pvp in an oil rotary vacuum pump, (C) is a waveform diagram showing a trigger signal, (D) is a waveform diagram showing opening and closing of a first on-off valve, (E) is a waveform diagram showing opening and closing of a second on-off valve, and (F) is measured with a vacuum gauge. FIG. 4G is a waveform diagram showing timing for reading the degree of vacuum, and FIG. 4G is a waveform diagram showing opening and closing of the leak valve. 5A is a timing chart showing the operation in the leak processing in the embodiment, FIG. 5A is a graph showing the vacuum pressure Pvc in the vacuum chamber, FIG. 5B is a graph showing the vacuum pressure Pvp in the oil rotary vacuum pump, and FIG. (D) is a waveform diagram showing opening and closing of the first on-off valve, (E) is a waveform diagram showing opening and closing of the second on-off valve, and (F) is a timing for reading the degree of vacuum measured by a vacuum gauge. (G) is a waveform diagram showing the opening and closing of the leak valve, and (H) is a waveform diagram showing a trigger signal for opening and closing the leak valve. It is a block diagram which shows schematic structure of the vacuum exhaust apparatus in other embodiment which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Vacuum exhaust apparatus 101 ... Vacuum chamber as a vacuum vessel 110 ... Oil rotary vacuum pump 121 ... First on-off valve as one on-off valve 122 ... Second on-off valve 130 on the other on-off valve 130 ... ... Leak tube as leak part 131 ... Leak valve 140 ... Vacuum gauge

Claims (10)

A vacuum exhaust device connected to a vacuum vessel and exhausting the vacuum vessel to a vacuum,
An oil rotary vacuum pump connected to the vacuum vessel and evacuating the vacuum vessel to a vacuum;
A pair of on-off valves provided in series between the vacuum vessel and the oil rotary vacuum pump;
A vacuum gauge which is provided between these open / close valves and measures the degree of vacuum;
Control means for controlling the open / closed state of the pair of on-off valves based on the degree of vacuum measured by the vacuum gauge,
When the oil rotary vacuum pump is driven, the control means opens one open / close valve connected to the vacuum container side for a predetermined period, and measures the vacuum in the vacuum container with the vacuum gauge measured by the vacuum gauge. The degree of vacuum on the oil rotary vacuum pump side measured by the vacuum gauge with the other open / close valve connected to the oil rotary vacuum pump side opened after the one open / close valve is closed After obtaining the pump vacuum degree data, and obtaining the vacuum degree on the oil rotary vacuum pump side, the stored container vacuum degree data and the pump vacuum degree data on the oil rotary vacuum pump side vacuum degree measured by the vacuum gauge; The degree of vacuum in the pump vacuum degree data relating to the degree of vacuum on the oil rotary vacuum pump side is the degree of vacuum in the stored vacuum vessel Upon recognizing that a degree of large vacuum above, the vacuum exhaust device which is characterized in that the control of the evacuation process of the pair of the opening and closing valve opened. The evacuation apparatus according to claim 1 ,
The control means is characterized in that the open state of the other on-off valve when acquiring the pump vacuum data relating to the degree of vacuum on the oil rotary vacuum pump side measured and acquired by the vacuum gauge is a predetermined period. Vacuum exhaust device. The evacuation apparatus according to claim 1 or 2 ,
The control means obtains pump vacuum data relating to the degree of vacuum on the oil rotary vacuum pump side, and then the degree of vacuum in the vacuum vessel measured by the vacuum gauge with the pair of on-off valves opened is a predetermined degree of vacuum. When it is recognized, the other opening / closing valve is closed. The evacuation apparatus according to claim 3 ,
The control means enables the oil rotary vacuum pump to be stopped after control to close the other open / close valve after the degree of vacuum in the vacuum container reaches a predetermined degree of vacuum. Vacuum exhaust device. The evacuation apparatus according to claim 3 or 4 ,
When the oil rotary vacuum pump that has been stopped due to a decrease in the degree of vacuum in the vacuum vessel is driven, the control means opens the one on-off valve and closes the other on-off valve. The container vacuum degree data relating to the degree of vacuum in the vacuum vessel measured by the vacuum gauge in a state is stored, and after the container vacuum degree data is stored, the one on-off valve is closed and then the other on-off valve The stored vacuum degree data of the container and the pump vacuum degree data on the vacuum degree on the oil rotary vacuum pump side, which is sequentially measured by the vacuum gauge, to compare the vacuum degree on the oil rotary vacuum pump side. When it is recognized that the degree of vacuum in the pump vacuum degree data is greater than the degree of vacuum stored in the stored vacuum container, the one of the opening degree data is opened. Evacuation apparatus characterized in that the control of the vacuum re-exhaust process of the valve in an open state. A vacuum exhaust apparatus according to any one of claims 1 to 5 ,
A leak part is provided that is branched between the vacuum vessel and the one on-off valve connected to the vacuum vessel side, and includes a leak valve that leaks between the vacuum vessel and the one on-off valve to atmospheric pressure by opening. A vacuum exhaust device characterized by that. The evacuation apparatus according to claim 6 ,
The control means opens the leak valve after closing the other opening / closing valve connected to the oil rotary vacuum pump side, and the degree of vacuum in the vacuum vessel measured by the vacuum gauge is substantially atmospheric pressure. If it is recognized, the other open / close valve is opened, and the leakage process is controlled to stop driving the oil rotary vacuum pump. A vacuum exhaust apparatus according to any one of claims 1 to 5 ,
An evacuation apparatus comprising a leak portion that is branched between the pair of on-off valves and includes a leak valve that leaks between the pair of on-off valves to atmospheric pressure when opened. The evacuation apparatus according to claim 8 ,
Wherein, the oil rotating the second on-off valve connected to a vacuum pump side said leak valve was Hirakijo on purpose after closed, Hirakijo state of the one-off valves to be connected to the vacuum container side and then, the degree of vacuum in the vacuum container measured by the vacuum gauge recognizes that almost atmospheric pressure, the deliberately other Hirakijo off valve, the oil rotary leak handling the vacuum pump to stop driving A vacuum evacuation device characterized by controlling The vacuum container to a vacuum evacuation method for evacuating a vacuum,
Using an oil rotary vacuum pump that evacuates the vacuum vessel to a vacuum via a pair of open / close valves connected in series, and a vacuum gauge that measures the degree of vacuum provided between the pair of open / close valves ,
When the oil-rotary vacuum pump is driven, the vacuum chamber vacuum storing container vacuum-degree data about the vacuum degree measured by the vacuum gauge off valve of hand that connects to the vacuum vessel side as the open state in a predetermined time period Degree storage process,
After this container vacuum degree storing step, the oil-rotary vacuum measured by the vacuum gauge other hand-off valves to connect to the oil-rotary vacuum pump after the one of the opening and closing valve was closed the open state Oil rotary vacuum pump vacuum degree acquisition process to acquire pump vacuum degree data on the pump side vacuum degree,
After this oil rotary vacuum pump vacuum degree acquisition step, the stored container vacuum degree data is compared with the pump vacuum degree data relating to the vacuum degree on the oil rotary vacuum pump side measured by the vacuum gauge, and the oil rotary vacuum When it is recognized that the degree of vacuum in the pump degree of vacuum data relating to the degree of vacuum on the pump side is greater than the degree of vacuum stored in the stored vacuum vessel, the pair of on-off valves are opened. And a vacuum exhausting step of exhausting the inside of the vacuum container to a vacuum by the driven oil rotary vacuum pump.

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