WO2016021616A1

WO2016021616A1 - Scroll-type fluid machine

Info

Publication number: WO2016021616A1
Application number: PCT/JP2015/072139
Authority: WO
Inventors: 和昭佐藤
Original assignee: アネスト岩田株式会社
Priority date: 2014-08-08
Filing date: 2015-08-04
Publication date: 2016-02-11
Also published as: JP2017186906A

Abstract

A scroll-type fluid machine having: a housing; a fixed scroll fixed to the housing and having a fixed wrap formed on an end plate; a revolving scroll housed inside the housing, pivotally supported by an eccentric shaft integrally formed with a main shaft that is coupled to a motor, said revolving scroll having a revolving wrap formed on an end plate, said revolving wrap forming a sealed chamber as a result of engaging with the fixed scroll; and a rotation-prevention mechanism that prevents rotation of the revolving scroll and causes orbital motion thereof, when the main shaft rotates. The revolving scroll has a boss section in the center thereof. The boss section includes: a closing wall section that closes a side facing a discharge port; and a shaft hole into which the eccentric shaft is rotatably inserted.

Description

Scroll type fluid machine

The present disclosure relates to a scroll fluid machine.

As described in Patent Document 1, for example, a conventional scroll fluid machine is rotatably supported by a fixed scroll, a main shaft that can be rotated by a motor, and an eccentric shaft portion that is formed integrally with the main shaft. And an orbiting scroll that can revolve by rotation of the main shaft, and a rotation prevention mechanism that revolves while preventing the orbiting scroll from rotating. This scroll type fluid machine forms a sealed chamber between the orbiting wrap and the fixed wrap by meshing the fixed wrap of the fixed scroll and the orbiting scroll of the orbiting scroll by the revolving motion of the orbiting scroll by the rotation of the drive shaft. Then, the gas sucked from the suction port is introduced into the sealed chamber, moved in the central direction and compressed, and the compressed gas is discharged from the discharge port.

A shaft hole is provided in the center portion of the orbiting scroll, and the eccentric shaft portion is inserted into the shaft hole up to the orbiting lap so that the radial load point and the support point of the eccentric shaft portion are made coincident with each other by the compressed gas in the orbiting scroll. . Thus, the scroll fluid machine is improved in performance so that no overturning moment is generated in the orbiting scroll.

JP 7-332258 A

In the scroll fluid machine described in Patent Document 1, the eccentric shaft portion is rotatably inserted into the shaft hole of the orbiting scroll, and the shaft hole passes through the orbiting scroll and opens on the side facing the discharge port. Therefore, in a non-sealed scroll type fluid machine that does not include a hermetic casing, dust, water, and the like may enter the bearing portion of the shaft hole via the exposed discharge port, leading to a cause of failure.

This disclosure describes a scroll fluid machine that prevents a capsize moment from acting on the orbiting scroll and prevents intrusion of dust, water, and the like into the shaft hole of the orbiting scroll.

A scroll fluid machine according to an aspect of the present disclosure includes a housing, a fixed scroll fixed to the housing and having a fixed lap formed on an end plate, and an eccentricity integrated with a main shaft housed in the housing and connected to a motor. A revolving motion that is pivotally supported by the shaft portion and that forms a revolving wrap that forms a sealed chamber by meshing with the fixed scroll on the end plate, and prevents the revolving motion of the revolving scroll when the main shaft rotates. A rotation preventing mechanism that revolves, and the orbiting scroll revolves so that the gas sucked from the suction port is introduced into the sealed chamber and moved from the outer peripheral side toward the center to be compressed, and the compressed gas is compressed by the fixed scroll. The orbiting scroll has a boss part in the center part, and the boss part is on the side facing the discharge port. A busy closing wall, the eccentric shaft portion is characterized in that it comprises a shaft hole which is inserted rotatably.

In some embodiments, the orbiting scroll may be provided with a thrust bearing.

In some embodiments, an escape space is formed between the closed wall and the discharge port facing the closed wall so as to communicate with the sealed chamber near the center of the sealed chamber, and the gas introduced into the sealed chamber is Finally, it may be discharged from the discharge port through the escape space. When the escape space is formed, the resistance of the discharge flow path can be reduced, high efficiency can be obtained, and the discharge port can be reduced to reduce the size of the scroll type fluid machine.

In some embodiments, the height of the boss portion in the axial direction is lower than the height of the orbiting wrap, and the blocking wall is separated from the end plate of the fixed scroll in the axial direction, so that at least the escape space on the orbiting scroll side. May be formed. When the escape space is formed at the center of the orbiting scroll, the resistance of the discharge flow path can be reduced, high efficiency can be obtained, and the discharge port can be reduced to reduce the size of the scroll fluid machine. Can do.

In some embodiments, a relief space may be formed at least on the fixed scroll side by providing a groove portion communicating with the discharge port on the end plate of the fixed scroll.

According to some embodiments of the present disclosure, a shaft hole is formed in the center portion of the orbiting scroll so that the side facing the discharge port is blocked by the blocking wall and the eccentric shaft portion is inserted to the orbiting wrap. As a result, it is possible to prevent an overturning moment from acting on the orbiting scroll, and to prevent entry of dust, water and the like into the shaft hole of the orbiting scroll, thereby eliminating the cause of the failure.

FIG. 1 is a vertical side view of a scroll vacuum pump according to an embodiment of the present disclosure. 2 is a longitudinal sectional view taken along line II-II in FIG. FIG. 3 is an enlarged longitudinal sectional side view of a main part. FIG. 4 is an exploded perspective view of the scroll type vacuum pump as viewed obliquely from the front. FIG. 5 is an exploded perspective view of a main part as viewed obliquely from the rear. FIG. 6 is a vertical side view of a scroll vacuum pump according to another embodiment of the present disclosure.

Hereinafter, an embodiment of the present disclosure will be described based on the drawings. FIG. 1 is a vertical side view showing a scroll vacuum pump 1 according to an embodiment of the present disclosure. In the following description, the left side in FIG. 1 is defined as “front”, and the right side is defined as “rear”.

As shown in FIGS. 1 and 4, the scroll type vacuum pump 1 of the present embodiment includes an annular housing 2 formed of, for example, an aluminum alloy, and a disc-shaped bearing plate 2A on the rear side of the housing 2. A fixed scroll 4 fixed to the front side of the housing 2, a main shaft 5 in the front-rear direction that rotates together with the rotating shaft 31 of the motor 3, and a turning scroll 6 that revolves as the main shaft 5 rotates. And an Oldham ring 10 that prevents the rotating motion of the orbiting scroll 6 and enables the revolving motion. In the scroll type vacuum pump 1, the revolving scroll 6 is revolved by the rotation of the main shaft 5, whereby the gas sucked from a container (not shown) that is brought into a vacuum state from the suction port 8 formed on the outer periphery of the housing 2. And the orbiting scroll 6 are introduced into a sealed chamber 7 and compressed in the direction of the center, and then discharged from a discharge port 9 formed at the center of the fixed scroll 4. .

The front part of the rotating shaft 31 of the motor 3 is rotatably supported by a radial bearing 20 installed at the center part of the bearing plate 2A. The rear end portion of the rotating shaft 31 of the motor 3 is rotatably supported by the radial bearing 21 at the center portion of the motor casing 32.

An eccentric shaft portion 51 is integrally formed at the front end portion of the main shaft 5. The rear end portion of the main shaft 5 is fitted and fixed to the outer periphery of the front end portion of the rotating shaft 31 of the motor 3. With this configuration, the main shaft 5 rotates as the rotating shaft 31 rotates. The orbiting scroll 6 is rotatably supported by the eccentric shaft portion 51 of the main shaft 5 via the radial bearing 12, and the dynamic unbalance due to the revolving motion of the orbiting scroll 6 is provided at the substantially central portion in the axial direction of the main shaft 5. A balance weight 13 for balancing is fixed.

The fixed scroll 4 is fixed to the front part of the housing 2 with bolts 11 facing rearward. On the rear surface of the disk-shaped end plate 41 of the fixed scroll 4, a fixed wrap 42 having a predetermined height and being spiral is integrally formed. A discharge port 9 for discharging the gas compressed in the sealed chamber 7 is formed at the center of the end plate 41 of the fixed scroll 4. A large number of cooling fins 43 are integrally formed on the front surface of the end plate 41.

The orbiting scroll 6 has a disc-shaped end plate 61. On the front surface of the end plate 61, a swirl wrap 62 having a predetermined spiral height that engages with the fixed wrap 42 of the fixed scroll 4. It is integrally formed. A boss 64 having a shaft hole 63 is integrally formed at the center of the end plate 61. An eccentric shaft portion 51 is rotatably inserted into the shaft hole 63 via the radial bearing 12.

The orbiting scroll 6 revolves without rotating with respect to the fixed scroll 4 as the main shaft 5 rotates by being supported in the housing 2 via the Oldham ring 10 as will be described later.

The fixed wrap 42 and the orbiting wrap 62 are engaged with each other so as to form a sealed chamber 7 between the fixed scroll 4 and the orbiting scroll 6. Band-

shaped seals

14 a and 14 b are respectively embedded in the distal ends of the fixed wrap 42 and the turning wrap 62. The

seals

14a and 14b keep the sealed chamber 7 in a sealed state by contacting the opposing surfaces.

With the revolution of the eccentric shaft portion 51 of the main shaft 5, the orbiting scroll 6 revolves with respect to the fixed scroll 4, so that the gas sucked from the suction port 8 is sequentially shifted from the outer peripheral side to the center side of the sealed chamber 7. Sent and compressed. The gas compressed in the sealed chamber 7 is finally discharged from the discharge port 9 of the fixed scroll 4 through the escape space 71 described later.

As shown in FIG. 3, the axial direction (forward) height h2 of the boss portion 64 of the orbiting scroll 6 is lower than the height h1 of the orbiting wrap 62. The boss portion 64 includes a thin blocking wall 65 that blocks the front surface of the shaft hole 63 at a position facing the discharge port 9 of the fixed scroll 4. The front surface of the blocking wall 65 is opposed to the discharge port 9 of the fixed scroll 4 with a slight distance. Between the blocking wall 65 and the discharge port 9, an escape space 71 is formed which is a small space communicating with both the closed chamber 7 a (see FIG. 2) near the center of the sealed chamber 7 and the discharge port 9. Yes. The blocking wall 65 is spaced apart from the rear surface of the end plate 41 of the fixed scroll 4 in the axial direction. The escape space 71 is formed between the rear surface of the end plate 41 and the front surface of the blocking wall 65. In other words, the escape space 71 is formed on the orbiting scroll 6 side.

Further, as shown in FIG. 3, in a state where the eccentric shaft portion 51 is inserted into the shaft hole 63 of the orbiting scroll 6, the eccentric shaft portion 51 penetrates the end plate 61 and has a height h <b> 1 of the orbiting wrap 62. More than the dimension corresponding to / 2, the shaft hole 63 is inserted. In other words, the depth d in the axial direction of the shaft hole 63 is formed so as to be shallower than the height h1 of the turning wrap 62 and deeper than ½ of the height h1. As a result, the radial load point acting on the orbiting scroll 6 by the compressed gas in the sealed chamber 7 and the support point of the eccentric shaft portion 51 are substantially matched so that no overturning moment is generated in the orbiting scroll 6. .

Further, since the front surface of the boss portion 64 facing the discharge port 9 is blocked by the blocking wall 65, the intrusion of dust, water, and the like entering from the discharge port 9 into the shaft hole 63 is prevented, and the orbiting scroll 6 Smooth revolving motion can be maintained for a long time.

Furthermore, since the escape space 71 is formed at the center of the orbiting scroll 6, it is possible to reduce the resistance of the discharge flow path, to obtain high efficiency, and to make the discharge port 9 small so that the scroll type vacuum can be obtained. The pump 1 can be downsized.

As shown in FIGS. 4 and 5, the front of the ears 68 (three ears 68 in this embodiment) formed on the outer periphery of the end plate 61 of the orbiting scroll 6 is behind the fixed scroll 4. A plate-shaped thrust bearing 15 having excellent wear resistance capable of contacting the side facing surface is fixed, and the rear surface of the end plate 61 is also provided with wear resistance capable of contacting the front facing surface in the housing 2. An excellent annular thrust bearing 16 is fixed. The

thrust bearings

15 and 16 make the revolving motion of the orbiting scroll 6 smooth by receiving a thrust load acting on the orbiting scroll 6.

The Oldham ring 10 includes a ring-shaped main body 101, a pair of front claws 102 provided at positions facing each other across the center of the front surface of the main body 101, and a rear surface of the main body 101 90 in the circumferential direction with respect to the front claws 102. And a pair of rear claws 103 provided at positions shifted by.

Each front claw 102 is slidably fitted into a pair of guide grooves 66 formed on the rear surface of the orbiting scroll 6, and each rear claw 103 is paired with a pair of guide grooves 66 formed on the inner surface facing the front side of the housing 2. Are slidably fitted in a direction perpendicular to the sliding direction of each front claw 102. Thereby, the orbiting scroll 6 can revolve without rotating by the linear reciprocating motion in the radial direction with respect to the Oldham ring 10 by the rotation of the eccentric shaft portion 51 of the main shaft 5.

An annular groove 67 is provided on the rear surface of the end plate 61 of the orbiting scroll 6 on the outer peripheral side of the thrust bearing 16 and on the inner peripheral side of the Oldham ring 10. In the concave groove 67, there are an annular ring seal 17 that contacts the inner surface facing forward in the housing 2, and an annular elastic body (backup seal) 18 that has a repulsive force that presses the annular seal 17 against the inner surface of the housing 2. Buried.

The annular seal 17 seals the rear surface of the orbiting scroll 6 and the inner surface of the housing 2, so that the inner space formed on the rear side of the end plate 61 of the orbiting scroll 6 in the housing 2 is on the outer peripheral side of the annular seal 17. Is divided into an outer peripheral space 22 formed on the inner periphery side and an inner peripheral space 23 formed on the inner peripheral side of the annular seal 17.

The outer peripheral side space 22 is in the outermost periphery of the sealed chamber 7 and communicates with the suction chamber 7b in a low pressure environment lower than the atmospheric pressure by following a flow path indicated by an arrow in FIG. Thereby, the pressure environment of the outer peripheral side space 22 becomes the same as the pressure environment of the suction chamber 7b when the scroll vacuum pump 1 is operated, and becomes a low pressure environment lower than the atmospheric pressure. Note that an annular seal 24 is maintained in a sealed state between the front surface of the housing 2 and the rear surface of the fixed scroll 4 facing the front surface. Thereby, the outer peripheral side space 22 is sealed in the state connected to the suction chamber 7b.

Next, the operation of the scroll type vacuum pump 1 having the above configuration will be described. When the rotating shaft 31 of the motor 3 rotates, the eccentric shaft portion 51 revolves around the axis of the main shaft 5. Along with this, the orbiting scroll 6 is revolving with respect to the fixed scroll 4 while being prevented from rotating by the Oldham ring 10. Thereby, each contact location of each lap | wrap 42,62 of each

scroll

4,6 moves toward a center part, and the low pressure gas introduce | transduced into the sealed chamber 7 from the suction inlet 8 in connection with this moves to the center. Compressed while moving in a spiral toward the part, discharged from the discharge port 9 through the escape space 71 formed at the center of the orbiting scroll 6.

The outer peripheral side space 22 communicates with the suction chamber 7b as described above. During the vacuum operation described above, the suction chamber 7b in the sealed chamber 7 is in a low pressure environment lower than the atmospheric pressure, so the pressure environment in the outer peripheral space 22 is the same low pressure environment as the suction chamber 7b. Further, since the sealed chamber 7a near the center of the sealed chamber 7 is not sealed, it becomes an atmospheric pressure environment. As a result, the backward pressure acting on the outer peripheral part and inner peripheral part of the orbiting scroll 6 and the pressure in the outer peripheral side space 22 and the inner peripheral side space 23 are balanced with each other. Therefore, it is possible to prevent the orbiting scroll 6 from revolving smoothly.

Further,

thrust bearings

15 and 16 are provided on the front and rear surfaces of the orbiting scroll 6, respectively. The

thrust bearings

15 and 16 effectively receive a load in the thrust direction acting on the orbiting scroll 6 to enable more stable revolving motion of the orbiting scroll 6.

The embodiments of the present disclosure have been described above, but various modifications and changes can be made to the embodiments without departing from the gist of the invention.

For example, as shown in FIG. 6, a scroll type vacuum pump 1 </ b> B in which a groove portion communicating with the discharge port 9 is provided in the end plate 41 may be used. By providing this groove portion, an escape space 72 is formed which is a small space communicating with both the sealed chamber 7a (see FIG. 2) near the center of the sealed chamber 7 and the discharge port 9. The groove portion, that is, the escape space 72 has, for example, a cylindrical shape, and is provided in the center portion 45 on the rear surface side of the end plate 41. In other words, the escape space 72 is formed on the fixed scroll 4B side. In this case, the height in the axial direction (forward) of the boss portion 64 of the orbiting scroll 6 </ b> B is substantially equal to the height of the orbiting wrap 62. The blocking wall 65 is close to the rear surface of the end plate 41 of the fixed scroll 4 with a slight gap. Even with the scroll vacuum pump 1B having such a relief space 72, the same functions and effects as those of the scroll vacuum pump 1 are achieved. According to the escape space 72, the resistance of the discharge flow path can be reduced, and high efficiency can be obtained. Furthermore, it is possible to reduce the size of the scroll vacuum pump 1B by reducing the discharge port 9.

The escape space 71 formed on the orbiting scroll 6 side in the scroll type vacuum pump 1 shown in FIG. 1 and the escape space 72 formed on the orbiting scroll 6B side in the scroll type vacuum pump 1B shown in FIG. 6 are combined. Also good. In that case, the escape space 71 and the escape space 72 communicate with each other. Relief spaces are formed on both the orbiting scroll side and the fixed scroll side.

(I) Instead of the Oldham ring 10, another configuration may be adopted as a configuration that enables the revolving motion by preventing the orbiting scroll 6 from rotating. (Ii) The scroll fluid machine may employ a compression pump instead of the vacuum pump.

According to some aspects of the present disclosure, the rollover moment is prevented from acting on the orbiting scroll. Intrusion of dust, water, etc. into the shaft hole of the orbiting scroll is prevented and the cause of the failure is eliminated.

DESCRIPTION OF

SYMBOLS

1, 1B Scroll type vacuum pump 2 Housing 2A Bearing plate 3

Motor

4, 4B Fixed scroll 5 Main shaft 6, 6B Orbiting scroll 7 Sealed chamber 7a Closed chamber 7b near the center Suction chamber 8 Suction port 9 Discharge port 10 Oldham ring 11 Bolt 12 Radial bearing 13

Balance weight

14a, 14b Seal 15 Thrust bearing 16 Thrust bearing 17 Annular seal 18

Elastic body

20, 21 Radial bearing 22 Outer peripheral space 23 Inner peripheral space 24 Seal 31 Rotating shaft 32 Motor casing 41 End plate 42 Fixed lap 43 Cooling fin 51 Eccentric shaft part 61 End plate 62 Revolving wrap 63 Shaft hole 64 Boss part 65 Closure wall 66 Guide groove 67 Recessed groove 68 Ear part 71 Relief space 72 Relief space 101 Main body 102 Front claw 103 Rear claw

Claims

A housing;
A fixed scroll fixed to the housing and having a fixed wrap formed on an end plate;
A revolving scroll that is housed in the housing and is pivotally supported by an eccentric shaft portion that is integral with a main shaft that is connected to a motor, and that forms a revolving wrap that forms a sealed chamber by meshing with the fixed scroll on an end plate. When,
A rotation preventing mechanism for revolving while preventing the rotation of the orbiting scroll when the main shaft rotates,
By revolving the orbiting scroll, the gas sucked from the suction port is introduced into the sealed chamber and compressed by moving from the outer peripheral side toward the center, and the compressed gas is provided at the center of the fixed scroll. It is configured to discharge from the discharge port,
The orbiting scroll has a boss portion at a center portion, and the boss portion includes a blocking wall that closes a side facing the discharge port, and a shaft hole into which the eccentric shaft portion is rotatably inserted. Scroll type fluid machine characterized by
The scroll fluid machine according to claim 1, wherein a thrust bearing is provided on the orbiting scroll.
Between the closed wall and the discharge port facing the closed wall, an escape space communicating with a sealed chamber closer to the center of the sealed chamber is formed,
The scroll fluid machine according to claim 1 or 2, wherein the gas introduced into the sealed chamber is finally discharged from the discharge port through the escape space.
The height in the axial direction of the boss portion is lower than the height of the turning wrap,
4. The scroll fluid machine according to claim 3, wherein the escape space is formed at least on the orbiting scroll side by separating the blocking wall from the end plate of the fixed scroll in the axial direction.
The scroll fluid machine according to claim 3, wherein the escape space is formed at least on the fixed scroll side by providing a groove portion communicating with the discharge port on the end plate of the fixed scroll. .