JP2536571B2 - Eddy current type turbo machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention provides a spiral motion to a fluid by rotation of an impeller such as a vortex type vacuum pump, a compressor and a turbine, and converts this angular kinetic energy into pressure. The present invention relates to an improvement of a vortex flow type turbomachine.

(Prior Art) Conventionally, as a vortex type turbomachine of this type, for example, as disclosed in JP-A-52-142313,
An impeller having a large number of blades is rotatably arranged in a housing, the impeller is rotated by driving a drive motor, and a fluid is sucked into a main flow path in the housing through a suction port of the housing, and in the main flow path. It is known that a fluid is compressed while being spirally moved in the axial direction of the main flow path and is discharged from the discharge port to the outside of the housing.

As shown in FIG. 8, the impeller of this vortex type turbomachine is formed by radially extending a large number of blades (c) on an outer peripheral surface (b) of a hub (a). It faces the main flow path (e) in the housing (d). And
The blade (c) is formed in a fan shape from the front surface of the hub (a) to the outer peripheral surface of the rear end, and the fluid flows into the blade (c) from the root of the leading edge (f) of the blade and the outer circumference of the hub. The flow follows the circular arc surface of the surface (b), flows out from the outer periphery that is the blade trailing edge (g), and then flows back from the root of the blade leading edge (f), and repeats this operation to make a spiral motion. become.

(Problems to be Solved by the Invention) However, in the above-described vortex flow turbomachine, the blades (c) largely protrude into the main flow path (e), and the hub outer peripheral surface (b) is formed into a fan shape having a central angle of about 90 degrees. Since it is formed, the rotational movement distance of the fluid in the blade (c) is large, and the advance angle of the fluid with respect to the axial direction of the main flow path (e) is large, that is, after the fluid flows into the blade (c). The distance traveled in the axial direction of the main flow path (e) was increased until it flowed out, and the number of rotations of the fluid was small while flowing through the main flow path (e) from the suction port to the discharge port. Moreover, since the fluid interferes with each blade (c) and a large fluid loss occurs, there is a problem that the flow velocity decreases. Therefore, the fourth
As shown by the broken line (P1) in the figure, the pressure ratio between the suction pressure and the discharge pressure is low, and the pressure ratio is low throughout the entire range regardless of the magnitude of the exhaust speed, resulting in poor compression efficiency.

In view of such a point, the present invention allows the fluid to pass through the blades in a substantially straight manner over both end surfaces of the hub to reduce the lead angle of the fluid generated by the blades and reduce the interference with the blades. The purpose is to improve the compression efficiency.

(Means for Solving the Problems) In order to achieve the above-mentioned object, means taken by the present invention are
As shown in FIGS. 1 and 2, first, a hollow annular portion (23) in which a fluid inlet (61) and a fluid outlet (62) are opened.
A housing (2) having is provided. And
A main fluid flow path (24) is formed in the hollow annular portion (23) of the housing (2). In addition, the housing (2) has a hub (31) connected to the drive shaft (7) and extending in a direction orthogonal to the drive shaft (7), and has an inner circumference of the main flow path (24). Multiple blades (32, 32,…) facing the section
On the outer peripheral surface (31a) of the hub, which is formed in a substantially cylindrical surface in the drive axis direction, from the suction port (61) to the main flow path (2).
It is intended for a vortex type turbomachine in which an impeller (3) for storing the fluid sucked in 4) to be compressed while being spirally transferred and to be discharged from the discharge port (62) to the outside of the housing (2). Furthermore, the impeller (3) has a hub outer peripheral surface (31a).
Form a part of the main flow path (24), and the fluid flow when passing through the blades (32) is configured to be substantially an axial flow in the drive axis direction. On the other hand, the main flow path (24) is formed in an annular space having a circular cross section where only a plurality of blades (32, 32, ...) Face, and at the end of the main flow path (24) on the outlet side of the blade (32). The passage width (S) between the direction point and the blade trailing edge (32b) is formed longer than the span length (L) from the hub outer peripheral surface (31a) to the tip of the blade (32).

(Operation) With the above configuration, in the present invention, when the impeller (3) is rotated, the fluid is sucked into the main flow path (24) through the suction port (61), and the blade leading edge ( 32a) flows into the blade (32), flows out from the trailing edge (32b), rotates in the main flow path (24), and then flows into the blade (32) again. The fluid then flows in the axial direction of the main flow path (24) while being rotated by obtaining angular kinetic energy from the blades (32), and is compressed by this spiral motion and discharged from the discharge port (62) to the outside of the housing (2). To be done.

Therefore, the fluid passes through the blades (32) substantially straight across the both sides of the hub (31) of the impeller (3) to obtain angular kinetic energy, and the advancing angle of the fluid generated by the blades (32) is increased. Since the number of rotations of the fluid increases and the number of times the fluid passes through the blades (32) increases, the applied angular kinetic energy also increases, and the compression efficiency can be significantly improved compared to the conventional case.

Further, since the fluid does not interfere with the blade (32) and smoothly forms a vortex, the flow velocity can be increased,
The compression efficiency can be further improved.

(Example) Hereinafter, the Example of this invention is described in detail based on drawing.

As shown in FIG. 1 and FIG. 2, (1) is a compression pump as a vortex type turbomachine, which is adapted to spirally transfer and compress various fluids such as gas while discharging them.

The compression pump (1) is configured by housing an impeller (3) in a housing (2), and the housing (2) is a first housing member (21) divided into left and right in FIG. And the second housing member (22) are integrally formed. The housing members (21, 22) are continuously formed on the disk portions (21a, 22a) covering the both end surfaces of the impeller (3) and the outer peripheral edge of the disk portions (21a, 22a). It is composed of half torus parts (21b, 22b) having arcuate annular concave parts,
1b, 22b) form a hollow annular portion (23).

In the central annular portion (23), a main flow passage (24) for the fluid is constituted by an annular space, and the main flow passage (24) has a substantially complete cross section without a liquid guide member (core) or the like. It is composed of a circular space.

Furthermore, the main flow path (24) is provided with a stripper member (5) of a predetermined width on the inner peripheral surface of the hollow annular portion (23), and the main flow path (24) is divided into a high pressure side and a low pressure side. It is partitioned. Further, a guide path (51) through which the impeller (3) passes is provided in the inner peripheral portion of the stripper member (5), and the stripper member (5) is provided on one side (right side in FIG. 2). )
Includes a semi-torus part (21b) of the first housing member (21)
Has a fluid suction port (61) on the other side (on the left side in FIG. 2) of the second housing member (22).
There are fluid outlets (62) in b),
The fluid introduced from the suction port (61) and the fluid discharged from the discharge port (62) are configured so as not to merge at the stripper member (5).

On the other hand, the impeller (3) is configured by radially extending a plurality of blades (32) on an outer peripheral surface (31a) of a disk-shaped hub (31). Both end surfaces of the hub (31) are covered with the disk portions (21a, 22a) of the housing members (21, 22) in close proximity to each other, and the drive shaft (7) is provided at the center of the hub (31).
And the hub (31) extends in a direction orthogonal to the drive shaft (7). The drive shaft (7) is located concentrically with the main flow path (24) and the guide member (4), penetrates the disc portion (22a) of the second housing member (22), and is not shown, Is connected to a motor, and the impeller (3) is rotated by driving the motor.

The hub outer peripheral surface (31a) is formed as a cylindrical surface concentric with the drive shaft (7) and constitutes a part of the outer peripheral surface of the main flow path (24).

As shown in FIG. 3, the blades (32) of the impeller (3) project in the centrifugal direction from the hub outer peripheral surface (31a) and face the inside of the main flow path (24), and the tips thereof are the guides. It is formed so as to be close to the inner peripheral portion of the member (4). Further, the blade (32) is formed over both end surfaces of the hub (31), and when fluid passes from the blade leading edge (32a) to the trailing edge (32b), the hub (31) is moved from the front surface to the rear surface. The flow of the blade (32) when passing through the blade (32) becomes substantially an axial flow, and angular kinetic energy is applied to the fluid when passing through the blade (32).

As shown in FIG. 1, the main flow path (24) has a passage width (S) between the rearmost point on the outlet side of the blade (32) in the main flow path (24) and the blade trailing edge (32b). But the hub outer surface (3
It is formed longer than the span length (L) from 1a) to the tip of the blade (32) so that the fluid does not flow out of the tip of the blade (32) in a short circuit.

Further, the blade (32) is formed in a substantially crescent-shaped airfoil so as to have a predetermined warp, and the inflow angle (β ₁ ) and the outflow angle (β ₂ ) of the blade (32). Is formed at, for example, 45 °, and the inflow angle (β ₁ ) allows the fluid to smoothly flow into the blade (32), while the outflow angle (β ₂ )
By this, a large amount of energy is given to the blade (32) at the time of outflow.

Next, the compression operation of the compression pump (1) will be described.

First, when the motor is driven to rotate the drive shaft (7),
The impeller (3) rotates in the housing (2), and each blade (32, 32, ...) Rotates and moves in the main flow path (24). On the other hand, the fluid is sucked into the main flow path (24) in the housing (2) through the suction port (61), flows into the blade (32) through the blade leading edge (32a), and flows out through the trailing edge (32b). Then, the blade (32) gives angular kinetic energy to the fluid, rotates the outer peripheral portion of the main flow path (24), and then flows into the blade (32) again. Then, the fluid is transferred in the axial direction of the main flow path (24) while repeating the above-mentioned rotation, is spirally compressed, and is discharged from the discharge port (62) to the housing (2).
It will be discharged outside.

In particular, since the fluid passes through the blades (32) from the front surface to the rear surface of the hub (31), the advancing angle of the fluid generated by the blades (32) is small, and the main flow passage ( The axial distance of 24) decreases, and the number of rotations during the transfer from the suction port (61) to the discharge port (62) increases.

Moreover, as shown in FIG. 2, the fluid has a large advancing angle on the suction port (61) side, and the advancing angle decreases toward the discharge port (62), and the number of rotations increases. As the number of passes is increased, the angular kinetic energy given to the fluid is increased. Moreover, since the front edge (32b) side and the rear edge (32b) side of the blade (32) are curved and have a warp, the fluid smoothly flows into the blade (32) and the blade (32). A large amount of energy will be given when the water flows out.

Furthermore, since the blade (32) and the fluid do not interfere with each other and a swirl flow is smoothly formed, the flow velocity can be increased.

Further, since the passage width (S) on the outlet side of the blade (32) in the main flow path (24) is longer than the span length (L) of the blade (32), the fluid is short-circuited from the tip of the blade (32). It is possible to improve the performance without leaking to the.

Therefore, as shown by the solid line (P2) in FIG. 4, the pressure ratio between the suction pressure and the discharge pressure can be significantly improved compared to the conventional case (see the broken line (P1)), and the compression efficiency (pump efficiency) can be improved. Can be improved.

FIG. 5 shows another embodiment, in which the hollow annular portion (23 ') is formed in an oval shape, and the hub outer peripheral surface (31a') is slightly arcuate following the hollow annular portion (23 '). Has been formed.
Further, blades (3) protruding from the outer peripheral surface (31a ') of the hub are provided.
The meridian of 2 ') is formed in a fan shape. Other configurations, operations, and effects are the same as those of the previous embodiment.

6 and 7 show a composite vacuum pump (A1, A2) using the vortex type compression pump (1 ') of the present invention, in which air is removed from a vacuum chamber of a semiconductor manufacturing apparatus or the like to create a clean vacuum. It is what you create.

The compound vacuum pump (A1) shown in FIG. 6 has a screw groove type compression pump (S) and two vortex type compression pumps (1 ′, 1 ′) combined in multiple stages in a casing (10). It is stored. An inlet (10a) opened to the vacuum chamber is provided at the center of the upper part of the casing (10), and an outlet (10b) opened to the atmosphere is provided on the lower side surface. Further, in the casing (10), the drive shaft (11) is provided at the center.
Are provided vertically, and the drive shaft (11) is externally fitted so that the cylindrical boss member (11a) rotates integrally, and the upper end of the frame (10c) is located above the casing (10).
The lower end is rotatably fitted and supported by the bottom of the casing (10).

Further, a drive motor (12) is provided below the drive shaft (11).
The drive motor (12) is connected to a stator (12a) fixed to the casing (10) and a drive shaft (11).
Is inserted into the rotor (12b), and the drive shaft (1
1) is rotating.

The screw groove type compression pump (S) includes a pair of upper and lower disc-shaped rotors (13, 13) and a pair of upper and lower annular stators (14, 13).
14) are alternately superposed on each other, and are provided on the inlet (10a) side (upper part in FIG. 5) of the casing (10). The drive shaft (11) is fitted in the center of the rotors (13, 13) and horizontally fixed to the drive shaft (11), and both rotors (13, 13) are connected to the boss member (11).
a), which are installed side by side at a specified interval, and the drive shaft (1
It is made to rotate by the rotation of 1).

Further, the stator (14, 14) is horizontally fixed to the casing (10) at the outer peripheral edge portion, and the upper stator (14) is placed between the rotors (13, 13) and the lower stator (14). ) Are juxtaposed below the lower rotor (13), and each rotor (13, 13) and each stator (14, 14) are
Are provided so that the opposite surfaces are close to each other. Further, both sides of the upper stator (14) and the lower stator (1
4) spiral grooves (14a, 14a, 14a) are respectively formed on the upper surface of the rotor 4 to form three pump stages, and the rotor (13, 1
Air is sucked into the casing (10) from the inlet (10a) by the rotation of 3), introduced into the spiral grooves (14a, 14a, 14a), compressed, and sent to the vortex type compression pump (1 '). ing.

On the other hand, the vortex type compression pump (1 ') is similar to that shown in FIG. 1, but the drive shaft (11) penetrates the impeller (3) and the housing (2'), and the housing ( 2 ') is a disk part (21a', 22a) and a half-torus part (2
1b, 22b) and an outer box part (21c, 22c) for covering the cooling path (21d, 22d) in which cooling water or the like circulates inside the outer box part (21c, 22c).
Is made.

An inflow pipe (25a) and an outflow pipe (25b) for cooling water or the like are communicated with the cooling passages (21d, 22d). Further, although not shown, the discharge port (62) of the upper vortex type compression pump (1 ') is the suction port (61) of the lower vortex type compression pump (1').
Is in communication with.

Next, the operation of the composite vacuum pump (A1) will be described.

First, when the drive motor (12) is started, both the screw groove type compression pump (S) and the vortex type compression pump (1 ', 1') are started, and the air in the vacuum chamber is supplied from the inlet (10a) to the casing (10a). 10) It is sucked in. The sucked air is first transferred to both rotors (13, 1) of the screw groove type compression pump (S).
The rotation of 3) causes the upper spiral groove (1
4a) and spirals in the centripetal direction, then moves to the lower surface spiral groove (14a) and spirals in the centrifugal direction, then moves to the upper surface spiral groove (14a) of the lower stator (14), and again the centripetal direction The air is spirally moved and the air is compressed to about 10 Torr and discharged downward.

Subsequently, the air discharged from the screw groove type compression pump (S) is introduced into the main flow path (24) from the suction port (61) of the vortex type compression pump (1 ') on the inlet (10a) side, The rotation of the impeller (3) advances in the axial direction of the main flow path (24) while making a spiral motion in the main flow path (24), and during this spiral motion, angular kinetic energy is given by the blades (32) to be compressed. It After that, the air is discharged from the discharge port (62) of the vortex type compression pump (1 ') on the inlet (10a) side, and the suction port (61) of the vortex type compression pump (1') on the outlet (10b) side. )
Is sucked into the main flow path (24) of the compression pump (1 '),
In the same manner as described above, the spiral motion is performed, the compressed to about 760 Torr, the gas is discharged from the discharge port (62) and is discharged to the atmosphere from the outflow port (10b) of the casing (10).

The compound vacuum pump (A2) shown in FIG. 7 uses another screw groove type compression pump (S '), and the screw groove type compression pump (S') is connected to the drive shaft (11). And a spiral groove (15a) is formed in the outer peripheral surface of the rotor (15). Therefore, the casing (1
The air sucked into the casing (10) and the spiral groove (15)
After being introduced into the space of a) and compressed, it is sent to the vortex type compression pump (1 '). Other configurations, operations and effects are similar to those shown in FIG.

The present invention can be applied to various eddy-current turbomachines such as a turbine in addition to the compression pump (1).

Further, the blades (32) may be formed smaller than the thickness of the hub (31).

(Effects of the Invention) As described above, according to the vortex type turbomachine of the present invention,
Since the fluid passes through the vanes almost straight from the front surface to the rear surface of the hub, the advancing angle of the fluid generated by the vanes can be reduced, so that the spiral rotation of the fluid in the main passage increases. Since the number of passes through the blades increases, the angular kinetic energy given to the fluid increases, and the compression efficiency can be improved.

Further, since the fluid does not interfere with the blades and smoothly forms the vortex flow, the flow velocity can be increased and the compression efficiency can be further improved.

Further, the passage width on the outlet side of the blade in the main flow passage is
Since it is longer than the span length of the blade, the fluid does not flow out from the tip of the blade in a short circuit, and the performance can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 7 show an embodiment of the present invention, FIG. 1 is a vertical sectional view of a vortex type compression pump, and FIG. 2 is a sectional view taken along line II-II in FIG. , FIG. 3 is a development view taken along line III-III in FIG. FIG. 4 is a characteristic diagram of pressure ratio with respect to exhaust speed. FIG. 5 is a vertical sectional view of another vortex type compression pump, FIG. 6 is a vertical sectional view of a composite vacuum pump, and FIG. 7 is a vertical sectional view of another composite vacuum pump. FIG. 8 is a sectional view showing a main part of a conventional eddy-current turbomachine. (1 ', 1')-compression pump, (2,2 ')-housing, (3) -impeller, (23,23')-hollow annular part,
(24) …… Main flow path, (31) …… Hub, (31a) …… Hub outer peripheral surface, (32) …… Vane, (32a) …… Front edge, (32b)…
… Trailing edge, (A1, A2)… Composite vacuum pump.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-52-142313 (JP, A) JP-A-48-25902 (JP, A) Actual development Sho-57-57294 (JP, U) JP-B-46- 39385 (JP, B1) US Patent 3869220 (US, A)

Claims (1)

(57) [Claims] 1. A housing (2) having a hollow annular portion (23) in which a fluid inlet (61) and a fluid outlet (62) are opened.
A main fluid flow path (24) formed in the hollow annular portion (23) of the housing (2), and a hub connected to the drive shaft (7) and extending in a direction orthogonal to the drive shaft (7). The plurality of blades (32, 32, ...) Having the (31) and facing the inner peripheral portion of the main flow path (24) are formed on the hub outer peripheral surface (31a) formed in a substantially cylindrical surface in the drive axis direction. The fluid is housed in the housing (2) and is sucked into the main flow path (24) from the suction port (61) while being spirally transferred and compressed while being compressed from the discharge port (62) to the housing (2). 2) A vortex type turbomachine equipped with an impeller (3) for discharging to the outside, wherein the impeller (3) has a hub outer peripheral surface (31a) as a main flow path (2).
While forming a part of 4), the fluid flow when passing through the blades (32) is configured to be substantially an axial flow in the drive axis direction, while the main flow path (24) is composed of a plurality of sheets. It is formed in an annular space with a circular cross section, where only the blades (32, 32, ...) Face, and the passage between the rearmost point on the outlet side of the blade (32) in the main flow path (24) and the blade trailing edge (32b). A swirl type turbomachine characterized in that the width (S) is formed longer than the span length (L) from the outer peripheral surface (31a) of the hub to the tips of the blades (32).