Patent Description:
With recent developments in electronics, there is a rapidly growing demand for semiconductors such as memories and integrated circuits.

These semiconductors are manufactured by doping an extremely pure semiconductor substrate with an impurity to impart an electric property to the semiconductor substrate, forming a minute circuit on the semiconductor substrate by etching, or the like.

In addition, such operations must be performed inside a chamber in a high-vacuum state in order to circumvent the effect of airborne dust and the like. While vacuum pumps are generally used to exhaust the chamber, in particular, a turbo-molecular pump which is one of such vacuum pumps is frequently used from the perspectives of a small amount of residual gas, easy maintenance, and the like.

In addition, a semiconductor manufacturing process includes a large number of steps in which various process gases are caused to act on a substrate of a semiconductor, and a turbo-molecular pump is used not only to vacuumize the inside of a chamber but also to exhaust such process gases from the chamber.

The turbo-molecular pump is constituted by a pump main body and a control apparatus which controls the pump main body. In addition, conventionally, for the purpose of omitting an external cable for connecting the pump main body and the control apparatus to each other, configurations such as described in <CIT> and <CIT> are known in which a control apparatus is integrated with a side portion or a bottom portion of the pump main body.

The document <CIT> dicloses a similar configuration.

A pump main body or a semiconductor manufacturing apparatus is often provided with a cooling mechanism that utilizes water cooling. Therefore, when a control apparatus is integrated with a side portion of the pump main body, there is a risk that water droplets may infiltrate into the control apparatus in the event of a water leak or condensation around the pump main body. For this reason, the control apparatus must be equipped with a drip-proof structure and, in the case of <CIT>, a watertight sealing material is disposed between a casing of the control apparatus and a base portion.

However, the watertight sealing material is expensive and causes an increase in cost.

In addition, the integrated pump main body and the control apparatus are sometimes separated on-site during maintenance such as when only an internal circuit is to be replaced. Therefore, a structure that enables easy separation and easy handling while providing a drip-proof structure as described above is desired.

Furthermore, when a gap σ is provided between the bottom surface (lower surface) of the pump main body and a lid plate of a control unit in order to provide heat insulation between the pump main body and the control unit as described in <CIT>, there is a risk that water droplets due to a water leak, condensation, or the like from a cooling mechanism may infiltrate into a control apparatus through the gap σ when separating the control apparatus.

The present invention has been made in consideration of such conventional problems and an object thereto is to provide a vacuum pump and a control apparatus of the vacuum pump which inexpensively realizes a structure that is less likely to be infiltrated by water droplets without using a sealing material and which is equipped with a structure that enables a pump main body and the control apparatus to be readily separated and enables maintenance to be readily performed.

In order to achieve the object described above, the present invention (claim <NUM>) provides a vacuum pump in which a pump main body and a control apparatus that controls the pump main body are integrated with each other, wherein the control apparatus includes a cylindrical portion which protrudes from a chassis of the control apparatus and inside which a cable that connects the pump main body and the control apparatus to each other is passed, and a height of the cylindrical portion exceeds a height of a gap formed between a bottom portion of the pump main body and the chassis of the control apparatus.

Cooling by a water-cooled tube may cause condensation to form around the pump main body. In addition, there is a risk that water droplets may leak from the water-cooled tube during maintenance. Leaked water droplets are highly likely to infiltrate into the gap. Since the height of the cylindrical portion exceeds the height of the gap formed between the bottom portion of the pump main body and the chassis of the control apparatus, water droplets filling the gap are prevented from infiltrating from the inside of the cylindrical portion.

Accordingly, safety of circuits during maintenance work can be ensured. In addition, a drip-proof structure can be realized with a simple configuration without using a sealing material.

In addition, the present invention (claim <NUM>) is the invention of the vacuum pump, wherein the pump main body includes a relay chamber which houses a relay substrate to which an end portion of the cable is connected, and the relay chamber is provided with a detachable cover.

Removing the cover enables maintenance work in the relay chamber to be performed with ease. The pump main body and the control apparatus can be readily separated from each other by detaching the end of the cable from the relay substrate.

Furthermore, the present invention (claim <NUM>) is the invention of the vacuum pump, wherein a detachable plate that fastens the pump main body and the control apparatus to each other is provided in the bottom portion of the pump main body.

Providing the plate in the bottom portion of the pump main body enables the pump main body and the control apparatus to be integrated by simply changing the plate even when sizes of the pump main body and the control apparatus differ from each other. Therefore, for example, a single control apparatus can be freely combined with pump main bodies of different capacities. The plate is detachably fastened to the pump main body.

Furthermore, the present invention (claim <NUM>) is the invention of the vacuum pump, wherein the height of the cylindrical portion is formed so as to be higher than a combined height dimension of the gap and the plate.

The height of the cylindrical portion is formed so as to be higher than the combined height dimension of the gap and the plate. Therefore, even when water droplets land on an upper surface of the plate, the water droplets are not likely to infiltrate beyond the cylindrical portion.

Furthermore, the present invention (claim <NUM>) is the invention of the vacuum pump, wherein a base portion of the pump main body is provided with a base penetrating portion, and the height of the cylindrical portion is formed so as to be higher than a combined height dimension of the gap and the base penetrating portion.

Even when the base portion of the pump main body is provided with the base penetrating portion, by forming the height of the cylindrical portion so as to be higher than the combined height dimension of the gap and the base penetrating portion, the water droplets are not likely to infiltrate beyond the cylindrical portion.

Furthermore, the present invention (claim <NUM>) is the invention of the vacuum pump, wherein the cylindrical portion is constituted by a different member from the chassis of the control apparatus.

Furthermore, the present invention (claim <NUM>) is the invention of the vacuum pump, wherein an attachable and detachable lid is provided with respect to a side portion of the chassis of the control apparatus, the lid has a bent piece at one end thereof, and the bent piece is brought into contact with a surface of the plate.

Providing the side portion of the chassis of the control apparatus with an attachable and detachable lid enables maintenance work such as replacing a circuit board to be performed with greater ease. In addition, since the lid has a bent piece at one end thereof and the bent piece is brought into contact with the surface of the plate, water droplets are unlikely to infiltrate from between the end of the lid and the plate.

Furthermore, the present invention (claim <NUM>) is the invention of the vacuum pump, wherein an attachable and detachable lid is provided with respect to a side portion of the chassis of the control apparatus, the lid has a bent piece at one end thereof, and the bent piece is brought into contact with a surface of the base portion.

Providing the side portion of the chassis of the control apparatus with an attachable and detachable lid enables maintenance work such as replacing a circuit board to be performed with greater ease. In addition, since the lid has a bent piece at one end thereof and the bent piece is brought into contact with the surface of the base portion, water droplets are unlikely to infiltrate from between the end of the lid and the base portion.

Furthermore, the present invention (claim <NUM>) is the invention of the vacuum pump, wherein a lower end of the relay substrate does not protrude downward beyond a bottommost end of the pump main body.

Accordingly, when detaching the plate and placing the pump main body on a table, the pump main body can be placed on the table in a stable manner. A risk of damaging the relay substrate can also be reduced.

Furthermore, the present invention (claim <NUM>) is the invention of the vacuum pump, including a rotor shaft internally mounted to the pump main body and a front panel externally mounted to the control apparatus, wherein the lid is disposed within <NUM> degrees from a disposition direction of the front panel as viewed from a central axis of the rotor shaft.

A front side of a surface containing the front panel is often opened for convenience of operation and management. Therefore, the lid is disposed within <NUM> degrees from a disposition direction of the front panel as viewed from the central axis of the rotor shaft. Accordingly, an arrangement can be realized in which the lid and the cover can be readily removed without being obstructed by related apparatuses disposed around the pump main body.

As described above, since the present invention (claim <NUM>) is configured such that the control apparatus includes the cylindrical portion which protrudes from the chassis of the control apparatus and inside which a cable that connects the pump main body and the control apparatus to each other is passed, and a height of the cylindrical portion exceeds a height of the gap formed between the bottom portion of the pump main body and the chassis of the control apparatus, water droplets filling the gap are prevented from infiltrating from the inside of the cylindrical portion.

Hereinafter, an embodiment of the present invention will be described. <FIG> shows a configuration diagram of the embodiment of the present invention. In <FIG>, in a turbo-molecular pump <NUM>, a pump main body <NUM> and a control apparatus <NUM> are integrated.

An inlet port <NUM> is formed at an upper end of a cylindrical outer casing <NUM> of the pump main body <NUM>. A rotating body <NUM> in which a plurality of rotor blades 102a, 102b, 102c,. constituted by turbine blades for sucking and exhausting gas are radially formed in multiple stages in a circumferential portion inside the outer casing <NUM>.

A rotor shaft <NUM> is mounted to a center of the rotating body <NUM> and, for example, a so-called five-axis control magnetic bearing levitates and supports the rotor shaft <NUM> in midair and controls a position of the rotor shaft <NUM>.

As an upper radial electromagnet <NUM>, four electromagnets are arranged so as to form pairs along mutually orthogonal X and Y axes which are coordinate axes in a radial direction of the rotor shaft <NUM>. An upper radial sensor <NUM> constituted by four electromagnets is provided in proximity to and in correspondence with the upper radial electromagnet <NUM>. The upper radial sensor <NUM> is configured to detect a radial displacement of the rotating body <NUM> and to send the detected radial displacement to the control apparatus <NUM>.

In the control apparatus <NUM>, based on a displacement signal detected by the upper radial sensor <NUM>, excitation of the upper radial electromagnet <NUM> is controlled via a compensation circuit having a PID adjustment function and a position in the radial direction of an upper side of the rotor shaft <NUM> is adjusted.

The rotor shaft <NUM> is formed of a high magnetic permeability material (such as iron) or the like and is configured so as to be attracted by a magnetic force of the upper radial electromagnet <NUM>. The adjustment described above is respectively independently performed in an X axis direction and a Y axis direction.

In addition, a lower radial electromagnet <NUM> and a lower radial sensor <NUM> are arranged in a similar manner to the upper radial electromagnet <NUM> and the upper radial sensor <NUM> and adjust a position in the radial direction of a lower side of the rotor shaft <NUM> in a similar manner to the position in the radial direction of the upper side.

Furthermore, axial electromagnets 106A and 106B are arranged so as to vertically sandwich a disc-shaped metal disk <NUM> provided in a lower part of the rotor shaft <NUM>. The metal disk <NUM> is constituted by a high magnetic permeability material such as iron. An axial sensor <NUM> is provided in order to detect an axial displacement of the rotor shaft <NUM>, and the axial sensor <NUM> is configured such that an axial displacement signal thereof is sent to the control apparatus <NUM>.

The axial electromagnets 106A and 106B are configured so that excitation thereof is controlled based on the axial displacement signal via the compensation circuit having a PID adjustment function of the control apparatus <NUM>. The axial electromagnet 106A and the axial electromagnet 106B respectively attract the metal disk <NUM> upward and downward by magnetic force.

As described above, the control apparatus <NUM> is configured to appropriately adjust magnetic forces exerted on the metal disk <NUM> by the axial electromagnets 106A and 106B to magnetically levitate the rotor shaft <NUM> in the axial direction and hold the rotor shaft <NUM> in space in a contactless manner.

A motor <NUM> includes a plurality of magnetic poles circumferentially arranged so as to surround the rotor shaft <NUM>. Each magnetic pole is controlled by the control apparatus <NUM> so as to rotationally drive the rotor shaft <NUM> via an electromagnetic force which acts between the magnetic pole and the rotor shaft <NUM>.

A plurality of stator blades 123a, 123b, 123c,. are disposed across small gaps from the rotor blades 102a, 102b, 102c,. The rotor blades 102a, 102b, 102c,. are formed inclined by a prescribed angle relative to a plane perpendicular to an axial line of the rotor shaft <NUM> in order to respectively transport a molecule of exhaust gas downward when the exhaust gas collides.

In addition, the stator blade <NUM> is also formed inclined by a prescribed angle relative to a plane perpendicular to the axial line of the rotor shaft <NUM> and is disposed so as to alternate with the stages of the rotor blade <NUM> toward inside of the outer casing <NUM>.

Furthermore, an end of the stator blade <NUM> is supported in a state of being fitted and inserted between a plurality of stacked stator blade spacers 125a, 125b, 125c,.

The stator blade spacer <NUM> is a ring-shaped member constituted by, for example, a metal such as aluminum, iron, stainless steel, or copper or a metal such as an alloy containing these metals as components.

The outer casing <NUM> is fixed across a small gap in an outer circumference of the stator blade spacer <NUM>. A base portion <NUM> is disposed in a bottom portion of the outer casing <NUM>, and a threaded spacer <NUM> is disposed between a lower portion of the stator blade spacer <NUM> and the base portion <NUM>. In addition, an outlet port <NUM> which communicates with the outside is formed in a lower portion of the threaded spacer <NUM> in the base portion <NUM>.

The threaded spacer <NUM> is a cylindrical member constituted by a metal such as aluminum, copper, stainless steel, or iron or a metal such as an alloy containing these metals as components, and a spiral thread groove 131a is engraved in plurality on an inner circumferential surface of the threaded spacer <NUM>.

A direction of the spirals of the thread grooves 131a is a direction in which, when a molecule of exhaust gas moves in a direction of rotation of the rotating body <NUM>, the molecule is transported toward the outlet port <NUM>.

A rotor blade 102d is suspended from a lowermost portion which continues from the rotor blades 102a, 102b, 102c,. of the rotating body <NUM>. An outer circumferential surface of the rotor blade 102d is cylindrical in shape and overhangs toward the inner circumferential surface of the threaded spacer <NUM>, and is in proximity to the inner circumferential surface of the threaded spacer <NUM> across a prescribed gap.

The base portion <NUM> is a disc-shaped member constituting a base of the turbo-molecular pump <NUM> and is generally constituted by a metal such as iron, aluminum, or stainless steel.

Since the base portion <NUM> physically holds the turbo-molecular pump <NUM> and also has a function of a heat conductive path, a metal having both rigidity and high thermal conductivity such as iron, aluminum, or copper is desirably used.

In the configuration described above, when the rotor blade <NUM> is driven by the motor <NUM> and rotates together with the rotor shaft <NUM>, exhaust gas from the chamber is sucked through the inlet port <NUM> due to actions of the rotor blade <NUM> and the stator blade <NUM>.

The exhaust gas sucked from the inlet port <NUM> passes between the rotor blade <NUM> and the stator blade <NUM> and is transported to the base portion <NUM>. At this point, while a temperature of the rotor blade <NUM> rises due to frictional heat generated when the exhaust gas comes into contact or collides with the rotor blade <NUM>, conduction or radiation of heat generated in the motor <NUM>, or the like, this heat is transferred to the side of the stator blade <NUM> by radiation, conduction by a gas molecule of the exhaust gas, or the like.

The stator blade spacers <NUM> are joined to one another in an outer circumferential portion and transfers heat received by the stator blade <NUM> from the rotor blade <NUM>, frictional heat generated when the exhaust gas comes into contact or collides with the stator blade <NUM>, or the like to the outer casing <NUM> and the threaded spacer <NUM>.

The exhaust gas transported to the threaded spacer <NUM> is sent to the outlet port <NUM> while being guided by the thread grooves 131a.

In some cases, process gases are introduced in a high-temperature state into a chamber in order to enhance reactivity. In addition, once the process gases are cooled and a temperature thereof drops to a certain level when exhausted, the process gases may solidify and cause a product to be deposited in an exhaust system.

Furthermore, a process gas of this type may cool and solidify inside the turbo-molecular pump <NUM> and adhere to and accumulate on the interior of the turbo-molecular pump <NUM>.

When a deposit of a process gas accumulates inside the turbo-molecular pump <NUM>, the deposit may narrow a pump flow path and cause a decline in performance of the turbo-molecular pump <NUM>.

When a temperature near the outlet port is low, the product described above readily solidifies and adheres particularly near the rotor blade 102d and the threaded spacer <NUM>. In order to solve this problem, conventionally, a heater or an annular water-cooled tube (not shown) is wound around an outer circumference of the base portion <NUM> or the like and, for example, a temperature sensor (such as a thermistor) (not shown) is embedded in the base portion <NUM>, whereby heating by the heater or cooling by the water-cooled tube is controlled so as to keep the temperature of the base portion <NUM> at a constant high temperature (set temperature) based on a signal from the temperature sensor.

Next, a structure around terminals to which a control cable and a power cable are to be connected between the pump main body <NUM> and the control apparatus <NUM> will be described. <FIG> is an enlarged view of a structural portion around the terminal in <FIG>.

In <FIG> and <FIG>, a plate <NUM> for aligning fixed positions with the control apparatus <NUM> is attached to a bottom portion of the base portion <NUM>. A relay chamber <NUM> is formed in the base portion <NUM>, and the relay chamber <NUM> is provided with an attachable and detachable cover <NUM>. A space <NUM> which connects to the relay chamber <NUM> and which is to be used for wiring of a magnetic bearing, a motor, and the like inside the pump main body <NUM> is formed inside the base portion <NUM>. The space <NUM> is hermetically sealed by a hermetic connector <NUM> (to be described later) and is therefore filled with a vacuum atmosphere but, on the other hand, the control apparatus <NUM> and the relay chamber <NUM> are filled with an air atmosphere.

In addition, the hermetic connector <NUM> is mounted to a wall portion around a right end of the space <NUM>. A large number of pins <NUM> penetrate the hermetic connector <NUM>. A right end of the pin <NUM> is exposed and penetrates a small hole (not shown) of a relay substrate <NUM>. The pin <NUM> is soldered at the small hole portion of the relay substrate <NUM> with respect to the relay substrate <NUM> which provides connection to the control apparatus <NUM>.

A terminal <NUM> is disposed at a lower end of the relay substrate <NUM> and configured such that one end of a harness <NUM> is attachable and detachable to and from the terminal <NUM>.

A hole 150a that connects to the relay chamber <NUM> is formed in the plate <NUM>, and a hole 200a is formed in a portion of a ceiling wall (chassis) of the control apparatus <NUM> which faces the hole 150a. A depressed portion 200b is formed in an upper circumference of the hole 200a of the control apparatus <NUM>, and a hollow plate-like portion 221a formed in a bottom portion of a cylindrical member <NUM> is fixed by a bolt (not illustrated) to the depressed portion 200b. The cylindrical member <NUM> penetrates the hole 150a, and a height of the cylindrical member <NUM> is formed higher than an upper surface of the plate <NUM>. The cylindrical member <NUM> corresponds to the cylindrical portion, and a horizontal sectional shape of the cylindrical member <NUM> may be any shape including an ellipse or a rectangle.

Another end of the harness <NUM> passes through the cylindrical member <NUM> and the hole 200a, extends into the control apparatus <NUM>, and connected to a terminal of a circuit board <NUM> disposed inside the control apparatus <NUM>.

On the other hand, a control cable and a power cable (not shown) are connected to a left end of the pin <NUM> and passed inside the space <NUM>.

An attachable and detachable lid <NUM> is disposed in a right-side portion of a chassis that forms the control apparatus <NUM>. A bent piece 219a having been bent in an L-shape is provided at an upper end of the lid <NUM> so as to protrude outward. The lid <NUM> is screwed to a right end of the chassis of the control apparatus <NUM>, and the bent piece 219a is brought into contact with a lower surface of the plate <NUM>.

A gap <NUM> of around <NUM> is formed to provide heat insulation between the plate <NUM> and the control apparatus <NUM>. A bottom portion wall of the control apparatus <NUM> and the plate <NUM> are fixed by hexagon head bolt columns (not illustrated) having been erected at four corners of the control apparatus <NUM>. The gap <NUM> is secured by a height of the hexagon head bolt columns.

Next, an action of the embodiment of the present invention will be described.

Disposing the plate <NUM> in the bottom portion of the pump main body <NUM> enables the pump main body <NUM> and the control apparatus <NUM> to be integrated by simply changing the plate <NUM> even when sizes of the pump main body <NUM> and the control apparatus <NUM> differ from each other. Therefore, for example, a single control apparatus <NUM> can be freely combined with pump main bodies <NUM> of different capacities. The plate <NUM> is detachably fastened to the pump main body <NUM> by bolts.

A configuration can be adopted in which the lower end of the relay substrate <NUM> is extended downward so as to penetrate the inside of the cylindrical member <NUM>. However, with the configuration in which the lower end of the relay substrate <NUM> is extended downward, for example, when removing the plate <NUM> and placing the pump main body <NUM> on a table during an operation to attach and detach the pump main body <NUM> and the control apparatus <NUM>, the lower end portion of the relay substrate <NUM> not only comes into contact with the table first and prevents the pump main body <NUM> from being placed on the table in a stable manner but may also damage the relay substrate <NUM>.

In consideration thereof, desirably, the lower end of the relay substrate <NUM> does not protrude in an axial direction beyond the upper surface of the plate <NUM> or the bottom surface of the pump main body <NUM>.

Cooling by a water-cooled tube may cause condensation to form around the base portion <NUM>. In addition, there is a risk that water droplets may leak from the water-cooled tube during maintenance. Leaked water droplets are highly likely to infiltrate into the gap <NUM>. In particular, when the lid <NUM> has been removed, the likelihood of infiltration by water droplets further increases. In this case, while the water droplets are likely to flow into the depressed portion 200b, since the hollow plate-like portion 221a and the depressed portion 200b are hermetically fixed to each other by respective metal surfaces with bolts (not illustrated), water droplets are unlikely to infiltrate into the control apparatus <NUM>.

Furthermore, a greater hermetic effect is exhibited by increasing respective flatnesses of the bottom surface of the hollow plate-like portion 221a and the depressed portion 200b.

In addition, in case water droplets infiltrate the gap <NUM>, an incline may be provided in a direction perpendicular to the lid <NUM> in order to produce a drainage effect.

In addition, since the cylindrical member <NUM> penetrates the gap <NUM> and is formed higher than the thickness of the gap <NUM>, water droplets that fill the gap <NUM> are prevented from infiltrating from inside the cylindrical member <NUM>. Furthermore, even when water droplets land on the upper surface of the plate <NUM>, since the cylindrical member <NUM> is provided so as to protrude higher than the upper surface of the plate <NUM>, the water droplets are not likely to infiltrate beyond the cylindrical member <NUM>.

In addition, since the bent piece 219a having been bent in an L-shape is provided so as to protrude outward at an upper end of the lid <NUM> on a side of the pump main body <NUM>, water droplets are unlikely to infiltrate into the control apparatus <NUM>. Furthermore, since the bent piece 219a and the plate <NUM> are hermetically fixed to each other by respective metal surfaces with bolts (not illustrated), water droplets are also unlikely to infiltrate from between the upper end of the lid <NUM> and the plate <NUM>. Moreover, as will be described later, even in a configuration in which the base portion <NUM> is deformed without providing the plate <NUM>, a similar effect can be obtained by bringing the bent piece 219a into contact with the bottom surface of the base portion <NUM>.

As described above, a drip-proof structure can be inexpensively realized by a component configuration solely based on metal working such as sheet metal pressing and without the use of a sealing material. In addition, an operation to attach and detach the harness <NUM> by removing the cover <NUM> can be readily performed while providing a drip-proof function. Accordingly, the control apparatus <NUM> can be readily detached. Furthermore, even during on-site maintenance work, work such as replacing a circuit board inside the control apparatus <NUM> can be readily performed by opening the lid <NUM> while providing a drip-proof function.

In the embodiment of the present invention, the plate <NUM> is described as a member that is independent from the pump main body <NUM>. However, as represented by another embodiment shown in <FIG>, the base portion <NUM> of the pump main body <NUM> is deformed without providing the plate <NUM> as a separate member. In addition, the plate <NUM> may be disposed with respect to the pump main body <NUM> as a base bottom portion <NUM>. In this case, in a similar manner to a case where the plate <NUM> is interposed, a bottom portion wall of the control apparatus <NUM> and the base bottom portion <NUM> are fixed by hexagon head bolt columns (not illustrated) having been erected at four corners of the control apparatus <NUM>. Furthermore, the gap <NUM> is secured by the height of the hexagon head bolt columns. In addition, the base bottom portion <NUM> is provided with a base penetrating portion 151a that connects to the relay chamber <NUM>.

It should be noted that, in <FIG>, elements that are the same as those in <FIG> will be denoted by same reference signs and descriptions thereof will be omitted.

In this case, the lower end of the relay substrate <NUM> desirably ends on an inner side of the pump instead of an upper surface of the base penetrating portion 151a in a similar manner to that described earlier.

Furthermore, while the cylindrical member <NUM> is configured as an independent member in the embodiment of the present invention, as represented by another embodiment shown in <FIG>, a cylindrical portion <NUM> may be provided so as to protrude from the ceiling wall of the control apparatus <NUM>. A horizontal sectional shape of the cylindrical portion <NUM> may be any shape including an ellipse or a rectangle. It should be noted that, in <FIG>, elements that are the same as those in <FIG> will be denoted by same reference signs and descriptions thereof will be omitted.

In this case, the ceiling wall and the cylindrical portion <NUM> are integrally formed. While <FIG> shows an example in which the plate <NUM> is not provided but integrally formed with the pump main body <NUM> as the base bottom portion <NUM> of the pump main body <NUM> in a similar manner to <FIG>, alternatively, a configuration may be adopted in which the plate <NUM> being a member that is independent from the pump main body <NUM> is provided in a similar manner to <FIG> and <FIG>.

Next, a suitable arrangement method of the relay chamber <NUM>, the lid <NUM>, and the cover <NUM> will be described.

Generally, various apparatuses and equipment <NUM> such as a power supply and piping are arranged around a chamber of a semiconductor manufacturing apparatus. In such an environment, the turbo-molecular pump <NUM> is often suspended in a lower part of the chamber. In such a case, for example, as shown in <FIG>, a situation may occur in which surfaces other than a surface provided with a panel (a front panel <NUM>) on which a power supply switch, a connector for connecting to the power supply, a cable connector for communication with the semiconductor manufacturing apparatus, and the like of the control apparatus <NUM> are concentrated are surrounded by the apparatuses and equipment <NUM>. This is because at least a front side of the surface containing the front panel <NUM> needs to be opened for convenience of operation and management.

In such a case, in order to replace a circuit component on-site, desirably, only the control apparatus <NUM> is attachable and detachable in a state where the pump main body <NUM> is suspended in the lower part of the chamber. In addition, to this end, desirably, the lid <NUM> and the cover <NUM> are arranged so as to be readily removable without being obstructed by the apparatuses and equipment <NUM>. As shown in <FIG>, the control apparatus <NUM> can be readily pulled out toward a front side that is a disposition direction of the front panel <NUM> relative to the apparatuses and equipment <NUM>.

In this case, by disposing the relay chamber <NUM>, the lid <NUM>, and the cover <NUM> at positions close to the surface of the front panel <NUM> of the control apparatus <NUM>, a worker can access the relay chamber <NUM>, the lid <NUM>, and the cover <NUM> from an opened portion and on-site maintenance work can be readily performed. In other words, as shown in <FIG>, when taking ease of maintenance work into consideration, an angle α formed between a disposition direction L1 of the relay chamber <NUM>, the lid <NUM>, and the cover <NUM> and a disposition direction L2 of the front panel <NUM> as viewed from a center point O of the rotor shaft <NUM> of the turbo-molecular pump <NUM> is desirably within <NUM> degrees.

Claim 1:
A vacuum pump (<NUM>) in which a pump main body (<NUM>) and a control apparatus (<NUM>) that controls the pump main body (<NUM>) are integrated with each other, wherein
a gap is formed between a bottom portion (<NUM>) of the pump main body (<NUM>) and a chassis of the control apparatus (<NUM>), and
the control apparatus (<NUM>) includes a cylindrical portion (<NUM>) which protrudes from the chassis of the control apparatus (<NUM>),
characterized in that, inside the cylindrical portion (<NUM>), a cable that connects the pump main body (<NUM>) and the control apparatus (<NUM>) to each other is passed, and
a height of the cylindrical portion (<NUM>) exceeds a height of the gap.