JP2001123969A - Scroll fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the axial length in a scroll fluid machine and to easily change a driving shaft. SOLUTION: In a scroll fluid machine, turning laps 11 in a turning scroll 3 eccentrically arranged on the axis of a fixed scroll 2 are fitted between fixed laps 6 in the fixed scroll 2, the turning scroll 3 is made eccentric around the axis of the fixed scroll 2, and air between both laps 11, 6 is pressurized or depressurized. An eccentric shaft 18 in an eccentric bush 17 composed of a holding cylinder 19 and the eccentric shaft 18 eccentric to the holding cylinder 19 is fitted in the center of the turning scroll 3 so as to be freely rotated around the axis, and the tip of the driving shaft coaxial with the fixed scroll 2 is inserted in the holding cylinder 19 in the eccentric bush 17 so as to be freely pulled out and also so as to be integrally rotated with the holding cylinder 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an improvement in a scroll fluid machine such as a scroll air compressor or a scroll vacuum pump.

[0002]

2. Description of the Related Art Scroll fluid machines are roughly classified into a direct drive type in which an input shaft integral with an orbiting scroll in a scroll body and an output shaft of a motor are connected via a coupling, and a scroll fluid machine in a scroll body. There is a belt drive type in which the input shaft of the orbiting scroll is driven by a belt.

As described above, conventional scroll fluid machines are classified into those directly driven by a motor and those driven by a belt.
In each case, it was necessary to prepare a scroll main body having different configurations of the input unit and the power connection unit for the orbiting scroll.

[0004] In any of the drive systems, a fixed portion protrudes from the scroll body to the outside in order to connect an input shaft for the orbiting scroll to the drive portion. The length in the direction was large.

Further, since the input shaft of the scroll main body becomes long, it is necessary to support the input shaft with two bearings provided at different positions in the axial direction of the housing, which requires time and labor for assembling and maintaining accuracy. However, there is also a problem that the number of parts increases.

Further, conventionally, since the counterweight for balancing the eccentric load accompanying the turning of the orbiting scroll is mounted on the drive shaft, it takes time and trouble to mount and adjust the counterweight. The score was also to increase.

[0007]

SUMMARY OF THE INVENTION The present invention addresses substantially all of the above-described problems of conventional scroll fluid machines.
The purpose is to solve the problem effectively, and the specific means are as follows. (1) The orbiting wrap of the orbiting scroll arranged on the axis of the fixed scroll is fitted between the fixed wraps of the fixed scroll, and the orbiting scroll is swiveled around the axis of the fixed scroll. In the scroll fluid machine which pressurizes or depressurizes the air in the above, the eccentric shaft of the eccentric bush consisting of the holding cylinder and the eccentric shaft eccentric to it is inserted around the axis in the cylindrical boss of the orbiting scroll. The drive shaft is inserted into the holding cylinder of the eccentric bush so as to be freely detachable and rotatable integrally with the holding cylinder.

(2) In the above item (1), on the opposite side of the eccentric bush in the radial direction with respect to the eccentric direction of the eccentric shaft, the holding cylinder is provided with a radially protruding counterweight for balancing the eccentric load.

(3) In the above item (1) or (2),
The eccentric shaft of the eccentric bush is provided with a hollow portion for reducing the mass.

(4) In any one of the above items (1) to (3), the drive shaft is the output shaft of the motor.

(5) In any one of the above items (1) to (3), the drive shaft is rotated by a belt.

(6) In any one of the above items (1) to (5), the drive shaft is inserted into the holding cylinder of the eccentric bush with a fastening means such as a key so as to be integrally rotatable.

(7) In any one of the above items (1) to (5), the drive shaft is inserted into the holding cylinder of the eccentric bush with a set screw so as to be able to rotate integrally.

(8) In any one of the above items (1) to (7), the distance between the support point of the eccentric bush on the housing in the scroll body and the support point of the eccentric bush on the orbiting scroll is determined by the distance of the eccentric bush to the housing. The distance between the support point and the bearing on the non-load side of the drive shaft is at least 1/10.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred, non-limiting embodiments of the present invention will now be described with reference to the accompanying drawings.

FIG. 1 is a longitudinal sectional view showing one embodiment in which the present invention is applied to a scroll type air compressor, and FIG.
FIG. 2 is an enlarged vertical sectional view showing the eccentric bush in FIG. 1 and the vicinity of a mounting portion thereof. In FIG. 1, the left side is the outside,
The right side is inside. As shown in the figure, the scroll body
(1) includes a fixed scroll (2) and an orbiting scroll (3), and drives the orbiting scroll (3) with power.

The fixed scroll (2) is a disk-shaped fixed end plate.
Cooling fins (5) are provided on the outer surface of (4), and fixed end plates
(4) On the inner surface, involute shape or arc shape,
Alternatively, a fixing wrap (6) having a shape formed by combining an involute and an arc is provided so as to protrude in the axial direction.

At the radially outermost portion of the fixing wrap (6), a suction hole (8) is formed in the fixed end plate (4).
An intake filter (7) having an air filter following (8) is provided.

At the center of the fixed wrap (6), the fixed end plate (4) is provided with a discharge hole (9) facing outward in the axial direction. Cooling fins for cooling by passing cooling air are provided on the outer surface of the fixed end plate (4).
(5) is formed projecting.

The orbiting scroll (3) is a disc-shaped orbiting end plate.
On the outer surface of (10), a turning wrap (11) in the form of an involute or an arc, or a combination of an involute and an arc is projected in the axial direction, and on the inner surface of the turning end plate (10). Are formed by projecting cooling fins (12) for cooling by passing cooling air,
A cylindrical boss (13) protrudes inward from the inner surface of the boss.

A tip seal groove is formed in each of the tip ends in the axial direction of the revolving wrap (11) and the fixed wrap (6), and a tip seal is provided in the tip seal structure. Further, the orbiting wrap (1) in the orbiting scroll (3)
1) is engaged with the fixed wrap (6) of the fixed scroll (2). Accordingly, a compression chamber is formed in which the volume formed by the orbiting scroll (3) and the fixed scroll (2) decreases in the center direction with the orbit.

The orbiting scroll (3) has a cylindrical housing (1).
The fixed scroll (2) can be turned near the inner surface of the fixed scroll (2) with a predetermined amount of eccentricity.

Between the housing (14) and the orbiting scroll (3), as a rotation preventing mechanism for preventing the orbiting scroll (14) from rotating, a plurality (usually three sets) of pin crank mechanisms (15) are provided. ) Is provided.

The above is a scroll type air compressor.
Since it is a general configuration and is well known to related engineers,
I don't think there is a need for more detailed explanation.

In the present invention, an axial cylindrical boss (13) is provided inside a bearing plate provided on the inner side of the orbiting end plate of the orbiting scroll (3) via cooling fins (2).
Is provided inside the cylindrical boss (13) via a slewing bearing such as a roller bearing (hereinafter simply referred to as a slewing bearing) (16).
An eccentric shaft (18) outside the eccentric bush (17) is pivotally supported.

The eccentric shaft (18) is eccentrically connected to the large-diameter holding cylinder (19) of the eccentric bush (17), and the amount of eccentricity with respect to the latter is determined by the eccentric orbit of the orbiting scroll (3). Is equal to the quantity.

The eccentric shaft (1) in the eccentric bush (17)
8) On the opposite side of the radial direction to the eccentric direction,
(19) is provided with a radially protruding counterweight (20) for balancing the eccentric load.

An axial keyway is provided on the inner surface of the holding cylinder (19).
(21) is engraved, and a plurality of screw holes (22) opening radially in the side wall of the holding cylinder (19) and opening at the bottom surface of the key groove (21).
(22) are arranged side by side in the axial direction.

In a portion connected to the eccentric shaft (18), the holding cylinder (19) is pivotally supported by a bearing (23) such as a ball bearing in a receiving cylinder (14a) integral with the housing (14). Have been.

In order to minimize the eccentric load caused by the rotation of the eccentric bush (17) and reduce the load on the slewing bearing (16) and the like, it is desirable that the weight of the eccentric shaft (18) be as small as possible. In the embodiment, the eccentric shaft
(18) is provided with an axial lightening hole (18a).

In an area where the screw holes (22) and (22) can be seen, an appropriate number of window holes (24) are formed in the cylindrical wall of the housing (14) in a circumferential direction.

A motor (25) coaxial with the fixed scroll (2) is fixed to the right side of the housing (14), that is, inside, by, for example, bolting a flange (not shown).

The holding cylinder (19) has a motor as a drive shaft.
The distal end of the output shaft (26) of (25) is detachably inserted.

A rod extends across the axial keyway (27) formed at the tip of the output shaft (26) of the motor (25) and the keyway (21) on the inner surface of the holding cylinder (19). By fitting the key (28), the output shaft (26) is rotationally integrated with the holding cylinder (19). Instead of a bar key, another key such as a half-moon key can be used.

A push screw (29) is inserted into the screw hole (22).
With its tip, the bar key (28) is securely pressed and fixed. The window hole (24) is used for inserting a tool for turning the set screw (29).

The keyways (21) and (27) and the bar key (28) are omitted, and the output shaft (26) of the motor (25) is directly pushed by the set screw (29), so that the output shaft is connected to the eccentric bush (17). (26) may be fixed. Of course, engagement with splines and the like is also possible.

If necessary, the output shaft (26) of the motor (25) is removed, and instead, for example, the tip of a drive shaft (not shown) to which a belt driving pulley is fixed in place is attached. It can also be inserted into the holding cylinder (19) and fixed in the same manner as described above.

The support point of the ball bearing (23) in the receiving cylinder (14a) in the housing (14), that is, the point where the load can be assumed to be substantially acting, and the eccentric bush for the orbiting scroll (3) The distance (L1) to the support point of the slewing bearing (16) supporting the small diameter support shaft (18) of (17), the support point of the ball bearing (23), and the substantial Point of force, i.e. distance to the main bearing (30) on the non-load side
The ratio with (L2) is preferably as small as possible.
It has been found that this ratio is at least 1/10 or more suitable for normal use, and is usually in the range of 1/10 to 1/20.

By reducing the ratio, the swing of the orbiting scroll (3) with respect to the eccentric shaft (18) of the eccentric bush (17) becomes small, and the scroll fluid machine can be driven stably.

[0040]

According to the present invention, the drive shaft is adapted to be inserted into the holding cylinder of the eccentric bush of the scroll body so as to be able to be pulled out and removed therefrom. Since it does not protrude from the main body, the overall length of the scroll main body can be made shorter than that of the conventional scroll main body. Further, by configuring the main body of the scroll fluid machine having the eccentric bush, the same scroll main body can be used.
If necessary, the drive shaft can be easily replaced not only with the direct drive type but also with a different drive type such as a belt drive type. If necessary, the motor, which is the power source, can be easily removed, inspected and maintained, or replaced with another drive source having a different horsepower or frequency.

According to the second aspect of the present invention, since the counterweight is integral with the eccentric shaft, the number of parts is reduced, and it is not necessary to perform special position adjustment or the like for mounting the counterweight as in the prior art.

According to the third aspect of the present invention, the eccentric load caused by the rotation of the eccentric bush is reduced, and the load on the bearing and the like is reduced.

According to the fourth aspect of the present invention, a motor-driven type can be easily realized.

According to the fifth aspect of the present invention, a belt drive type can be easily used.

According to the sixth and seventh aspects of the present invention, the drive shaft can be easily attached to the holding cylinder in the eccentric bush.

According to an eighth aspect of the present invention, the swing of the orbiting scroll with respect to the eccentric shaft of the eccentric bush is small, and the scroll fluid machine can be driven stably.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view showing an embodiment of the present invention.

FIG. 2 is an enlarged vertical sectional side view showing the eccentric bush in FIG. 1 and the vicinity of a mounting portion thereof.

[Explanation of symbols]

 (1) Scroll body (2) Fixed scroll (3) Orbiting scroll (4) Fixed end plate (5) Cooling fin (6) Fixed wrap (7) Suction filter (8) Suction hole (9) Discharge hole (10) (11) Slewing wrap (12) Cooling fin (13) Cylindrical boss (14) Housing (14a) Receptacle (15) Pin crank mechanism (16) Slewing bearing (17) Eccentric bush (18) Eccentric shaft ( 18a) Lightening hole (19) Holding cylinder (20) Counter weight (21) Keyway (22) Screw hole (23) Bearing (24) Window hole (25) Motor (26) Output shaft (27) Keyway (28 ) Bar key (29) Set screw (30) Main bearing

Claims (8)

[Claims] An orbiting wrap of an orbiting scroll arranged on an axis of a fixed scroll is fitted between fixed wraps of the fixed scroll, and the orbiting scroll is turned around the axis of the fixed scroll.
In a scroll fluid machine configured to pressurize or depressurize the air between the two wraps, an eccentric shaft of an eccentric bush composed of a holding cylinder and an eccentric shaft eccentric to the holding cylinder is provided in a cylindrical boss of the orbiting scroll. That the drive shaft is inserted into the holding cylinder of the eccentric bush so that it can be removed and removed, and can rotate integrally with the holding cylinder. Features scroll fluid machinery. 2. An eccentric bush is provided with a counterweight projecting in a radial direction for balancing an eccentric load on a side opposite to an eccentric direction of an eccentric shaft of an eccentric shaft. 2. The scroll fluid machine according to 1. 3. The scroll fluid machine according to claim 1, wherein the eccentric shaft of the eccentric bush is provided with a hollow portion for reducing the mass. 4. The scroll fluid machine according to claim 1, wherein the drive shaft is an output shaft of a motor. 5. The scroll fluid machine according to claim 1, wherein the drive shaft is rotated by a belt. 6. The scroll fluid machine according to claim 1, wherein the drive shaft is inserted into the holding cylinder of the eccentric bush so as to be integrally rotatable with a key. 7. The scroll fluid machine according to claim 1, wherein the drive shaft is inserted into a holding cylinder of the eccentric bush with a set screw so as to be able to rotate integrally. 8. The distance between the support point of the eccentric bush with respect to the housing and the support point of the eccentric bush with respect to the orbiting scroll in the scroll body is determined by the distance between the support point of the eccentric bush with respect to the housing and the bearing on the non-load side of the drive shaft. The scroll fluid machine according to any one of claims 1 to 7, wherein the scroll fluid machine is at least 1/10.