JP2002332976A - Scroll type fluid machine - Google Patents

Abstract

(57) [Summary] [Problem] To reduce the load applied to a bearing. A bush (33) includes a movable scroll member (1).
In order to balance the centrifugal force generated by the circular orbital motion of No. 9, a counterweight 331 for generating a centrifugal force in the opposite direction is provided. The counterweight 331 adds an unbalance amount so as to be larger than the centrifugal force generated by the centrifugal force of the movable scroll member 19, and furthermore, a gas compression reaction force F applied to the bush 33.
An unbalance amount is also added to the counterweight 331 in the direction of decreasing y.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type fluid machine having a balance based on a movable scroll member and a counterweight which can oppose a change in the turning radius of the movable scroll member.

[0002]

2. Description of the Related Art As a prior art, there is disclosed a scroll type fluid machine in which the centrifugal force of a counterweight is made larger in the opposite direction than the centrifugal force of a movable scroll member.
No. 5984.

As shown in FIG. 4, a scroll type fluid machine according to the prior art has a front end plate 11.
And a cup-shaped casing 12 installed so as to be joined to the end face of the front end plate 11.

At the center of the front end plate 11,
A through hole 111 through which the main shaft 13 is inserted is formed.
On the back of the front end plate 11, a through hole 111 is provided.
And an annular protruding portion 112 concentric with the above. The casing 12 has its opening fitted and fixed on the annular projection 112 of the front end plate 11.

[0005] The joint surface between the front end plate 11 and the casing 12 is sealed by an O-ring 14 arranged on the annular projection 112. The front end plate 11 has a sleeve 15 protruding so as to surround the main shaft 13. A shaft seal assembly 16 is arranged in a space formed between the sleeve 15 and the main shaft 13.

Although the sleeve 15 may be formed integrally with the front end plate 11, in the example of FIG. 4, it is formed separately and attached to the front surface of the front end plate 11 by screws (not shown). . Sleeve 1
An electromagnetic clutch 17 is arranged on the outer circumference of the fifth clutch 5. The electromagnetic clutch 17 transmits the rotational motion of the external drive source to the main shaft 13 via a belt (not shown).

A fixed scroll member 18, a movable scroll member 19, a drive mechanism for the movable scroll member 19, and a rotation preventing mechanism 21 are arranged in the casing 12 whose opening is closed by the front end plate 11.

The fixed scroll member 18 includes a side plate 181.
(First plate body) and a spiral body (first spiral body) 182 fixed on one surface of the side plate 181. Side plate 1 on the opposite side to the surface on which the spiral body 182 is provided
A plurality of legs (not shown) are provided on the 81 surface. Each leg is fixed in the casing 12 by a screw 22 screwed from the outside of the end plate portion 121 of the casing 12 at its tip end surface.

An O-ring (not shown) is arranged between the head of the screw 22 and the end plate portion 121 to prevent fluid leakage along the screw 22. Also, the side plate 181
A groove is formed on the outer surface of the. O-
A ring 24 is arranged. The inside of the casing 12 is separated by a side plate 181 into a suction chamber 25 and a discharge chamber 26.

In the suction chamber 25, a movable scroll member 1 is provided.
9 are arranged. The movable scroll member 19 includes a side plate 191 (second plate) and a spiral body (second spiral body) 192 fixed on one surface of the side plate 191.

The spiral body 192 of the movable scroll member 19
Are the spiral bodies 182 and 180 of the fixed scroll member 18.
The vortex 18
2,192 to form a fluid pocket. The movable scroll member 19 is connected to a drive mechanism and a rotation prevention mechanism 21 which will be described later.
Then, the fluid orbits on a circular orbit of radius Ror by rotation to compress the fluid.

Here, the radius Ror of the circular orbit is generally given by
(Pitch of spiral body) −2 × (wall thickness of spiral body) / 2. Then, the center of the spiral of the spiral body 192 of the movable scroll member 19 is arranged to be separated from the center of the spiral of the spiral body 182 of the fixed scroll member 18 by a distance Ror.

Therefore, the rotation of the main shaft 13 causes the orbiting scroll member 19 to revolve on a circular orbit of radius Ror. Thereby, the line contact formed between the spirals 182 and 192 and defining the fluid pocket is formed by the spiral 1
82, 192 along the surface, so that the fluid pockets decrease in volume while the swirl 18
2,192. As a result, the fluid is compressed.

A casing 1 is provided in the compressor housing 10.
2 is provided with a suction port 29 and a discharge port 30 for connecting to an external fluid circuit. Here, the fluid introduced from the suction port 29 into the suction chamber 25 in the casing 12 is taken into a fluid pocket formed between the scroll members 18 and 19, and is compressed by the orbital motion of the movable scroll member 19. , Spiral body 182, 19
Move to the center of 2. The compressed fluid is discharged from the center chamber of the fluid pocket to the discharge chamber 26 through the discharge hole 218 formed in the side plate 181 of the fixed scroll member 18, and flows out to the fluid circuit through the discharge port 30.

Next, the driving mechanism of the movable scroll member 19 will be described with reference to FIGS. 4, 5 and 6. FIG. Spindle 13
Is rotatably supported by a ball bearing 31 disposed in the sleeve 15 of the front end plate 11. The inner end of the main shaft 13 has a disk rotor 1
31 are formed. This disk rotor section 131
Is rotatably supported by a ball bearing 32 disposed in a through hole 111 of the front end plate 11. At the tip of the disk rotor 131,
A drive pin 132 is provided at a position deviated from the center so as to protrude in the axial direction.

On the other hand, the side plate 19 of the movable scroll member 19
In FIG. 1, an annular boss 193 is formed on a surface opposite to the spiral body 192. A thick disk-shaped or short-axis bush 33 is fitted into the boss 193 so as to be rotatably supported via a needle bearing 34. The bush 33 has an arc-shaped plate-shaped counterweight 331 that extends integrally with the bush 33 in the radial direction.

The bush 33 is provided with an eccentric hole 332 at a position deviated from the center. This eccentric hole 33
2, a drive pin 132 is fitted. For this reason, the bush 33 is rotatably supported on the drive pin 132.

The rotation preventing mechanism 21, the ball bearings 31, 32, and the needle bearing 34 constitute a spiral drive bearing component.

As shown in FIGS. 5 and 6, the positional relationship between the center S of the main shaft 13, the center B of the bush 33, and the center D of the drive pin 132 according to the eccentric hole 332 of the bush 33 The distance between them is the above-mentioned orbit radius Ror, and the center D of the drive pin 132 is
, A line orthogonal to a line connecting the center B of the bush 33 and the center S of the main shaft 13 on the opposite side to the center S of the main shaft 13 and a line connecting the center S of the main shaft 13 and the center B of the bush 33 It is positioned so as to be on the side advanced in the rotation direction of the main shaft 13 (indicated by an arrow A in FIG. 6).

In such a configuration of the drive mechanism, the center B of the bush 33 can move on an arc having a radius B to D with the center D of the drive pin 132 as the center.
That is, when the main shaft 13 rotates, the bush 33 is pulled by the drive pin 132, and a force acts to move the center D of the bush 33 away from the center S of the main shaft 13, so that the spiral body 192 of the movable scroll member 19 is fixed to the fixed scroll. It contacts the side wall 191 of the spiral body 182 of the member 18.

Therefore, the center of the movable scroll member 19 orbits around the center S of the main shaft 13 with a radius Ror. At this time, the movable scroll member 19
Since the rotation is prevented by the rotation preventing mechanism 21, only the orbital movement is performed, and the rotation is not performed.

FIG. 7 is a view showing the basic circular coordinates of the spiral body 182 of the fixed scroll member 18 as reference coordinates, and when the driving pin is located on the X axis, the spiral body 182 of the fixed scroll member 18 and the fixed scroll member 19 spirals 1
92 shows the state of combination with 92.

First, in FIG. 7, the gas compressing force Fx generated in the X-axis direction is such that the seal points S1, S2, S3, S4 on the side walls of the spiral bodies 182, 192 are not on the same straight line in the horizontal direction. Therefore, assuming that the basic radius of the spiral body 192 is rg, an area (2 · rg · H) is added to the shift width 2 · rg and the spiral member wall height H of the scroll member.

The spiral body wall height H refers to the height of the spiral body 192 extending from the side plate 191 of the movable scroll member 19. Here, the seal points S1, S2, S3, S4
The pressure of each fluid pocket formed by
P2 and P1 from the center of 2,192 outward,
Assuming that the pressure at the outer periphery of the spiral bodies 182 and 192 is Po, the gas pressure Fx is Fx = 2 · rg · H · (P2
−P1) + 2 · rgH · (P1−P0) = 2 · rg · H
· It can be expressed as (P2-P0).

The gas compression reaction force F generated in the Y-axis direction
Since y is perpendicular to the line connecting the center of the bush 33 and the center of the main shaft 13, if the shaft torque is T and the orbit radius is ro, then T = ro · Fy, and the force as a compressive load is equal. Therefore, Fy = T / ro. Here, the gas compression reaction force refers to the fixed scroll member 18 shown in FIG.
And the gas generated by the movable scroll member 19 is compressed and generated by a pressure difference (P2> P1) between the rooms closed by the walls of the fixed and movable scroll members 18 and 19.

On the other hand, when the fluid is compressed by the orbital motion of the movable scroll member 19, the above-described reaction of the gas compression reaction force Fy is applied to the center B of the bush 33 by Fy in FIG.
Can be considered as acting as shown in FIG. Since the bush 33 is rotatable on the drive pin 132, the bush 33 receives a moment rotating around the center D of the drive pin 132 by the gas compression reaction force Fy. This moment can be expressed by Fy · L · sin α, where the angle between the direction of the gas compression reaction force Fy and the line connecting the center D and the center B is the angle α shown in FIG. Here, L is the distance between the center D and the center B.

As a result, the movable scroll member 19 supported on the bush 33 receives a moment that rotates around the center D of the drive pin 132. As a result, the spiral body 192 of the movable scroll member 19 is pressed against the side wall 181 of the spiral body 182 of the fixed scroll member 18. If this pressing force is fx, f
x = Fy · tanα.

The rotation of the movable crawling member 19 is prevented by the centrifugal force Fs of the movable scroll member 19 applied to the rotation preventing mechanism 21 and the force -FB acting in the crank direction, as shown in FIG. Done by force. Here, assuming that the rotational moment of the movable crawl member 19 is Ms, it is considered that the gas compression reaction force Fy acts on an intermediate point of a line connecting the center of the base circle of the spiral scroll 192 of the fixed scroll member 18 and the movable scroll member 19. For this reason, the difference between this action and the driving point generates a rotational moment Ms. When the center drive is performed, the drive point is made to coincide with the center of the base circle of the spiral body 192 of the orbiting scroll member 19, so that the amount of deviation from the point of action of the gas compression reaction force Fy is 1
/ 2 · ro. Therefore, the moment Ms is Ms =
Since ro / 2 · Fy, Ms = １ ／ · T.

When the rotation moment Ms is received by the rotation prevention mechanism 21 using a ball element, the distance from the rotation prevention point of the rotation prevention mechanism 21 to the bush 33 is L.
Then, Fs = Ms / L = 1/2 · T / L,
This reaction force -FB is applied to the bush 33 in the X-axis direction.

The bush 33 has a centrifugal force Fs generated by the orbital motion of the movable scroll member 19 and the bush 33 and a centrifugal force Fc generated by the motion of the counterweight 331 provided on the bush 33, in addition to the above-described forces. Each adds as shown in FIG.

The relationship between the forces acting on the bush 33 has been described above. The sum ΣXF of the forces applied in the X-axis direction is the force acting on the spiral body 192 of the movable scroll member 19, and when ΣXF> 0, Thus, the spiral body 192 of the movable scroll member 19 is pressed against the side wall of the spiral scroll 182 of the fixed scroll member 192. Here, the wall pressing force ΣXF, which is the sum in the X-axis direction, is ΣXF = fx
−Fa−Fs−Fc−Fx. In the conventional apparatus, ΔXF> 0 is set. However, setting ΔXF> 0 causes the following disadvantages.

That is, in the scroll type fluid machine, it is limited between the line contact portions of the spirally wound bodies 182 and 192 meshing with each other. The line contact portion is formed by the spiral members 182 and 192 by the relative circular orbital movement of the scroll member.
Along the surface of the whirlpool 1 while reducing its volume
Since the fluid moves toward the center of 82 and 192 to compress the fluid, it is necessary to ensure a sufficient sealing force at the line contact portion.

However, if the contact force is increased in order to ensure the sealing force, the spiral bodies 182 and 192 will be worn. In particular, when the scroll-type fluid machine is used at a high speed, the spiral body 192 of the movable scroll member 19 being driven is strongly pressed against the spiral body 192 of the fixed scroll member 18. Therefore, the driving force of the scroll-type fluid machine increases, and a large amount of abrasion powder is generated due to the abrasion of the spiral bodies 182 and 192, which adversely affects the scroll-type fluid machine or a system including the scroll-type fluid machine. Or, the mechanical efficiency is reduced.

Therefore, as shown in FIG. 10, the counterweights 33 are set so that ΔXF = 0 or ΔXF <0 at the upper limit of the number of rotations of the scroll type fluid machine.
One centrifugal force Fc is set.

As shown in FIGS. 5 and 9, the scroll type fluid machine has a rotatable angle range regulating mechanism. That is, the recessed portion 133 is formed on the end surface of the main shaft 13 facing the bush 33 of the disk rotor portion 131, and the protruding portion 333 is formed on the end surface of the bush 33 facing the recessed portion 133 of the disk rotor portion 131.
Is provided. The protruding portion 333 is fitted and arranged in the concave portion 133 with a gap. Here, the protrusion 33
3 can move within the recessed portion 133.
And the maximum gap between the spirally wound bodies 182 and 192 is determined by this.

FIG. 11 shows an example of static / dynamic balance. The unbalance amount of the movable scroll member 19 can be adjusted by the counter weight 331 and the balance weight 36 of the clutch armature. In FIG. 10, Us is the amount of unbalance of the movable scroll member 19, Uc is the amount of unbalance of the counterweight 331, Ub is the amount of unbalance of the balance weight 35, and Ua is the armature. Are the unbalance amounts of the balance weights 36, L1, L2, L
3 is the distance between each balance in the longitudinal direction with respect to the main shaft 13.

As described above, the centrifugal force Fc of the counterweight 331 provided on the bush 33 is set to be larger than the centrifugal force Fs generated by the orbital motion of the movable scroll member 19 and the bush 33. Excessive contact between the spiral bodies 182 and 192 during high-speed rotation is prevented, and wear between the spiral bodies 182 and 192 is suppressed to a small value.

However, since the centrifugal force Fs generated by the orbital motion of the movable scroll member 19 and the like and the centrifugal force Fc of the counterweight 331 satisfy Fc> Fs, an imbalance occurs and vibration is generated. For this reason, it is necessary to maintain the dynamic balance of the whole scroll type fluid machine.

Further, in the example of FIG. 4, balance weights 35 and 36 for generating centrifugal forces Fa and Fb on the main shaft 13 are provided.
Is provided. That is, in FIG. 1, a balance weight 35 that generates centrifugal force in the same direction as the counterweight 331 is disposed on the main shaft 13 at a position close to the counterweight 331, and the counterweight 331 is related to the balance weight 35. The armature balance weight 36 of the electromagnetic clutch 17 is disposed at the opposite position in the axial direction.

The balance weight 35 is connected to the main shaft 13.
And an armature balance weight 36 is integrally provided on a part of the electromagnetic clutch.

As described above, in the conventional scroll type fluid machine, as shown in FIG. 10, the load applied to the bush 33 is the gas compression reaction force Fy and the wall pressing force ΣXF (X
The resultant is the resultant F1 of the centrifugal force Fc of the counterweight 331, which generates a centrifugal force in the opposite direction to balance the centrifugal force generated by the axial sum ΣXF and the circular orbital movement of the orbiting scroll member 19.

[0042]

However, in the conventional scroll type fluid machine, the urging force for sealing the spiral body 192 of the movable scroll member 19 and the spiral body 182 of the fixed scroll member 18 is reduced at high speed. In addition, wear of the spirally wound bodies 182 and 192 is reduced. The gas compression reaction force (eccentric bushing driving force) Fy in this case, the urging force for sealing the spiral body 192 of the movable scroll member 19 and the spiral body 182 of the fixed scroll member 18, and the centrifugal force Fc of the counterweight 331 Of the bush 33
In addition, this load shortens the life of the drive bearing 34 fitted with the bush 33.

This load is also applied to other bearings 31 and 32 supporting the main shaft 13 as a moment load, and a bearing having a large load capacity must be used.

Therefore, an object of the present invention is to reduce the load applied to the drive bearing 34 fitted to the bush, and further reduce the load applied to the other bearings 3 and 32 supporting the main shaft. An object of the present invention is to provide a scroll-type fluid machine which enables use of a bearing having a small size and can reduce the cost of parts.

In particular, since the load is reduced when the number of rotations is high, high-speed operation is possible. Another object of the present invention is to provide a bushing without changing the wall pressing force and the static / dynamic balance. It is possible to reduce the load,
An object of the present invention is to provide a scroll-type fluid machine that can use a bearing having a small load capacity.

[0046]

According to the present invention, the rotation of the main shaft is eccentric by a predetermined distance with respect to the fixed scroll member by the large diameter portion of the main shaft, the bush, the counterweight, and the spiral drive bearing component. Compression is performed while moving the fluid from the outer circumference to the inner circumference of the movable scroll member by changing the revolving motion of the combined movable scroll member, and the bush is generated by the revolving motion of the movable scroll member. In order to balance against centrifugal force, in a scroll-type fluid machine having the counterweight that generates centrifugal force in the opposite direction, the counterweight is larger than the centrifugal force of the movable scroll member that generates centrifugal force. To reduce the gas compression reaction force applied to the bush. Scroll fluid machine is achieved, characterized in that that in the direction obtained by adding the amount of imbalance in the counterweight.

[0047]

According to the present invention, a centrifugal force is generated by adding an unbalance amount of the counterweight in the direction opposite to the gas compression reaction force. The unbalance amount is the product of the distance from the center of the rotating shaft of the solid having a mass attached to the rotating shaft to the center of gravity and the weight of the solid.

Also, the centrifugal force is generated by adding the direction of the unbalance amount and the angle of the drive pin position of the main shaft from the center of the bush to the direction of the centrifugal force. These resultant forces can reduce the load applied to the bush by increasing the rotation speed of the main shaft.

Further, an increase in the wall pressing force (wall pressing force (total)) due to the centrifugal force can be canceled by the centrifugal force due to the unbalance amount in the direction of the centrifugal force.

In addition, since the load applied to the bush is reduced, the moment load applied to the bearing fitted to the bush and other bearings supporting the main shaft is also reduced.

Further, the imbalance between the static and dynamic balance caused by adding the unbalance amount of the counterweight can be adjusted by the balance weight of the counterweight and the clutch armature.

[0052]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a scroll type fluid machine according to the present invention will be described with reference to the drawings. FIG. 1 shows the load applied to the eccentric bush.
FIG. 2 shows an example of static / dynamic balance. FIG. 3 shows the load / vector applied to the eccentric bush and the resultant force.

The scroll-type fluid machine according to the present embodiment has the same general configuration as that of the scroll-type fluid machine described in FIG. The description of the parts excluding the parts is omitted.

Referring to FIG. 3 together with FIGS. 1 and 2, the bush 33 is provided with a centrifugal force (movable) in the opposite direction to balance the centrifugal force Fs generated by the circular orbital movement of the movable scroll member 19. It has a counterweight 331 for generating a reaction force Fc) of the centrifugal force Fs of the scroll member 19.

The counterweight 331 adds the unbalance amount Fc1-Fc so as to be larger than the centrifugal force Fs of the movable scroll member 19, and also reduces the gas compression reaction force Fy applied to the bush 33 in the direction of decreasing the counterweight. 331 is added with the unbalance amount Uc2.

Next, referring to FIG. 2, the unbalance amount Vc1 of the counterweight 331 is represented by Uc, the unbalance amount for balancing the centrifugal force Us of the spiral body 192 of the movable scroll member 19. The angle of the position of the drive pin 132 of the main shaft 13 from the direction of the gas compression reaction force Fy applied to the bush 33 and the center of the bush 33 is α, and the unbalance amount added in the direction of decreasing the gas compression reaction force Fy is Uc.
Assuming that 2, the unbalance amount Uc1 of the counterweight 331 in the direction opposite to the centrifugal force Fs generated in the movable scroll member 19 is Uc1 = Uc + Uc2.times.tan.
α.

That is, the gas compression reaction force Fy shown in FIG.
The centrifugal force Fc2 is generated by adding the unbalance amount Uc2 of the counterweight 331 in the direction opposite to the above.

In the direction of the centrifugal force Fc 1, the unbalance amount Uc 2 × tan α (α is the direction of the gas compression reaction force Fy applied to the bush 33 and the center of the main shaft 1 from the center of the bush 33.
The centrifugal force Fc1 is generated by adding the angle of the third drive pin 132.

Further, the imbalance in static / dynamic balance caused by adding the unbalance amount Uc1−Uc of the counterweight 331 can be adjusted by the counterweight 331 and the balance weight 36 of the clutch armature.

As shown in FIG. 2, in order to maintain the overall dynamic balance, it is sufficient to set the following imbalance amounts.

Us: Unbalance amount of the spiral body 192 of the movable scroll member 19. Uc1: Unbalance amount of the counterweight 331. Ub1: Unbalance amount of the balance weight 35. Ua1: The amount of unbalance of the armature balance weight 36. Ub2: The unbalance amount of the balance weight 35 for adjusting the imbalance of the static / dynamic balance caused by the unbalance amount Uc2 added to the counterweight 331. Uc2: the amount of unbalance of the balance weight 35 added in the direction opposite to the gas compression reaction force Fy. Ua2: The unbalance amount of the clutch armature balance weight 36 for adjusting the imbalance of the static and dynamic balance caused by the unbalance amount Uc2 added to the counterweight 331.

Here, L1, L2, L3; assuming the distance between the respective balances in the longitudinal direction with respect to the main axis, Us-Uc1−Ub1 + Ua1 = 0 Uc2−Ub2 + Ua2 = 0 Ub1 · + Uc1 · (L2 + L3) −Us (L1) + L2
+ L3) = 0 Ub2.L3 -Uc2. (L2 + L3) = 0

Referring to FIG. 3, these gas compression reaction forces F
The resultant force F2 of y, the centrifugal force Fc2, the centrifugal force Fc1, and the wall pressing force ΣXF can reduce the load applied to the bush 33 by increasing the rotation speed of the main shaft 13.

The wall pressing force Σ due to the centrifugal force Fc2
The increase in the XF wall pressing force ΣXF is determined by the centrifugal force (Fc1) due to the unbalance amount Uc2 × tanα in the direction of the centrifugal force Fc2.
-Fc) to cancel.

Further, since the load applied to the bush 33 is reduced, the moment load applied to the bearing 34 fitted to the bush 33 and the other bearings 31 and 32 supporting the main shaft 13 is also reduced. .

A detailed description of the load and balance around the bush 33 and the bearing is disclosed in Japanese Patent Application Laid-Open No. Sho 59-215984.

The present invention can also utilize this technology for a vacuum pump or an expander as the scroll type fluid machine described above.

[0068]

According to the scroll type fluid machine of the present invention, the load on the drive bearing 34 fitted to the bush 33 is reduced, and the load on the other bearings 31 and 32 supporting the main shaft is also reduced. Since the bearing can be reduced, it is possible to use a bearing having a small load capacity, and the cost of parts can be reduced.

Further, the load on the bush can be reduced without changing the wall pressing force and the static / dynamic balance, and a bearing having a small load capacity can be used, thereby reducing the cost.

In particular, according to the scroll type fluid machine of the present invention, the load is reduced when the number of rotations is high, so that a high-speed operation can be performed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a load applied to an eccentric bush of a scroll type fluid machine of the present invention.

FIG. 2 is an explanatory diagram showing an example of a static / dynamic balance of the scroll type fluid machine of the present invention.

FIG. 3 is an explanatory diagram illustrating a load, a vector, and a resultant force applied to an eccentric bush of the scroll type fluid machine of the present invention.

FIG. 4 is a central sectional view of a scroll type fluid machine as a conventional technique.

FIG. 5 is an exploded perspective view of the driving mechanism used in FIG.

FIG. 6 is an explanatory diagram for explaining an operation of the eccentric bush of the scroll fluid machine shown in FIG. 4;

7 is an explanatory diagram for describing a force applied to a spiral body of a movable scroll member of the scroll fluid machine illustrated in FIG. 4;

FIG. 8 is an explanatory diagram for describing a force applied to an eccentric bush of the scroll type fluid machine shown in FIG. 4;

FIG. 9 is an explanatory diagram for explaining a force generated by a rotation preventing mechanism of the scroll fluid machine shown in FIG. 4;

10 is an explanatory diagram illustrating a load / vector and a resultant force applied to the eccentric bush of the scroll fluid machine illustrated in FIG. 4;

FIG. 11 is an explanatory diagram for explaining a static / dynamic balance of the scroll fluid machine shown in FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Compressor housing 13 Main shaft 18 Fixed scroll member 19 Movable scroll member 33 Bush 35, 36 Banlance weight 132 Drive pin 331 Counter weight

Claims (2)

[Claims] 1. A revolving motion of a movable scroll member combined with a rotation of a main shaft eccentrically combined with a fixed scroll member by a predetermined distance by a large-diameter portion of the main shaft, a bush, a counterweight, and a spiral drive bearing component. The compression is performed while moving the fluid from the outer circumference to the inner circumference of the movable scroll member, and the bush is provided to balance the centrifugal force generated by the revolving motion of the movable scroll member. In a scroll-type fluid machine having the counterweight that generates centrifugal force in the opposite direction, the counterweight adds an unbalance amount so as to be larger than the centrifugal force of the movable scroll member that generates centrifugal force. , And also in a direction to reduce the gas compression reaction force applied to the bush. Scroll fluid machine, characterized in that the addition of the unbalance amount to site. 2. The scroll-type fluid machine according to claim 1, wherein the unbalance amount of the counterweight is Uc, and the unbalance amount for balancing the centrifugal force of the movable scroll member is Uc. The angle of the drive pin position of the main shaft from the center of the bush and the direction of the gas compression reaction force applied to the shaft is α, and the unbalance amount added in the direction of decreasing the gas compression reaction force is Uc2.
Then, the unbalance amount Uc1 of the counterweight, which is provided in the direction opposite to the centrifugal force generated in the movable scroll member, is configured according to the following equation. Uc1 = Uc + Uc2 × tanα