JP2001123968A - Peripheral drive type double scroll compressor - Google Patents

Abstract

(57) [Summary] To provide a stable operation of an outer peripheral drive type scroll compressor for a long period of time. Specifically, the effect of misalignment of the drive shaft is reduced, and the effect of thermal deformation during operation is reduced. An orbiting-type double scroll compressor is provided with an orbiting scroll (3) having scroll wraps (3b, 3c) formed on both sides of an end plate (3a), and a pair of fixed scrolls (1, 2) made of aluminum alloy sandwiching the orbiting scroll from both sides. And The bearing housings 40 and 42 made of steel are attached to the end plate portion 1a of one fixed scroll. The rolling bearing 12a is press-fitted into the drive shaft to provide a minute gap between the bearing housing and the bearing outer ring. An elastic body 45 is arranged between the outer ring of the rolling bearing and the bearing retainer to elastically support the rolling bearing in the thrust direction and the radial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor, and more particularly, to an outer peripheral drive type double scroll compressor having an orbiting scroll having scroll wraps formed on both sides of a head plate and suitable for air compression.

[0002]

2. Description of the Related Art An example of a scroll fluid machine for compressing gas by interlocking a revolving scroll and a fixed scroll having a spiral wrap formed on a head plate and compressing gas is disclosed in Japanese Patent Application Laid-Open No. HEI 5-1993.
-52189. The formation of wraps on both sides of a head plate is disclosed in Japanese Patent Application Laid-Open No. 7-259759.

[0003] Among them, the one described in Japanese Patent Application Laid-Open No. 7-259759 is called a double scroll compressor, and operates a compression working chamber in an oil-free state (a state without lubricating oil). In any of the above publications, the orbiting scroll is orbitally driven by a drive shaft arranged on the outer peripheral portion. The drive shaft is rotatably supported by a rolling bearing held by a fixed scroll member.

[0004] In each of the scroll compressors described in the above publications, the orbiting scroll is driven by a drive shaft having two crank portions. Another example of a compressor in which a compressor element is driven by two drive shafts is disclosed in Japanese Patent Laid-Open No. 3-160182.
No. in the official gazette. What is described in this publication is a screw compressor, which has two rotors. Each rotor is rotatably supported at both ends by rolling bearings.
The rotor shaft is straight, and the bearings are arranged in a single row or double rows in the fixed casing.

[0005]

In the case of the scroll compressor described in the above prior art, the orbiting scroll is sandwiched between a pair of fixed scrolls, and two drive shafts are attached to the outer peripheral portion of the orbiting scroll. Due to the accumulated errors of the manufacturing errors of the scrolls and the machining errors of the shafts and the unevenness of the bearing gap, the gap of the bearing portion may not be properly maintained. If the clearance between the bearings is not appropriate, the two main drive shafts and the auxiliary drive shaft may be mounted non-parallel in a V-shape or V-shape. This causes frictional wear of the scroll wrap or galling of the bearing.

In order to prevent the non-parallel mounting of the two shafts, if the mounting holes of the shafts are integrally formed with the orbiting scroll and the fixed scroll, the scroll wrap portions of the scrolls interfere with each other. There is a possibility that a situation where processing cannot be performed may occur. If the radial gap between the scroll wraps is increased to prevent this interference, the performance of the compressor is reduced.

Furthermore, in the double scroll compressor of the outer peripheral drive type, even if the gap between the scroll wraps is made appropriate and the two drive shafts can be assembled in parallel, the center part and the peripheral part of the orbiting scroll during the operation can be obtained. In this case, a temperature distribution occurs due to the heat of compression, and thermal deformation occurs. As a result, it becomes difficult to keep the gaps between the various parts of the scroll compressor at the desired gaps, and there is a fear that the bearing life may be shortened due to galling or an increase in the bearing load.

On the other hand, in the screw compressor described in Japanese Patent Application Laid-Open No. 3-160182, unlike a scroll compressor in which one compression element is driven by two drive shafts, two compression elements are driven by each shaft. Since the motor is driven, no trouble occurs due to the positioning of the drive shaft. Therefore, the screw compressor does not have the above-mentioned problems of the outer peripheral drive type double scroll compressor.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned disadvantages of the prior art, and has as its object to stably operate an outer peripherally driven scroll compressor for a long period of time.

[0010]

In order to achieve the above object, the present invention comprises a pair of fixed scrolls having spiral wraps formed thereon, and a revolving scroll having wraps meshing with the wraps formed on both sides of a head plate. And an outer peripheral drive type double scroll compressor including a main drive shaft and an auxiliary drive shaft for driving the outer peripheral portion of the orbiting scroll via bearing means, wherein at least one of the pair of fixed scrolls is provided separately from the fixed scroll. A bearing housing is provided for holding the body bearing means.

Preferably, the fixed scroll is made of an aluminum alloy and the bearing housing is made of an iron-based metal; or the bearing means has a rolling bearing, and the inner surface of the bearing housing and the outer ring of the rolling bearing are connected to each other. A minute gap is formed between them during assembly.

In order to achieve the above object, in the above features, the inner diameter of the bearing housing is further reduced on the scroll wrap surface side than on the opposite surface side; the bearing means includes a rolling bearing and a bearing retainer for holding the rolling bearing. An elastic body is mounted between the outer ring of the rolling bearing and the inner surface of the bearing housing, and the bearing retainer and the rolling bearing are arranged such that the elastic body can change its volume; A bearing presser, and the rolling bearing is press-fitted into at least one of the main drive shaft and the auxiliary drive shaft, and has a clearance fit with the bearing housing;
An elastic body is interposed between the bearing retainer and the outer ring of the rolling bearing; the bearing means has a rolling bearing and is provided with a pin that engages with both the outer ring of the rolling bearing and the bearing housing; Preferably, the bearing housing is made of steel and the aluminum alloy fixed scroll and the steel bearing housing are integrated by casting.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As described above, in an outer peripheral drive type double scroll fluid machine, an orbiting scroll is arranged so as to be included in a pair of fixed scrolls. Since the components are arranged so as to penetrate, there is a problem in that assembly errors are likely to accumulate due to misalignment between components, or thermal deformation occurs during operation.

Specifically, for each scroll member,
Although it is indicated in the drawing that the center of each bearing is machined with high accuracy, the machining center distances after machining may be different for each component because the machining accuracy for each individual product cannot be the same.
As a result, if two drive shafts are assembled at the stage where one fixed scroll and the orbiting scroll are engaged, it is difficult to keep the drive shafts completely parallel to each other.

Since the distance between the centers of the bearings of the fixed scroll and the orbiting scroll is different, the arrangement of the drive shaft in the vertical section of the drive shaft tends to be in the shape of a letter V or V. Therefore, when assembling the other fixed scroll, the dimension between the bearings of the fixed scroll and the dimension between the centers of the front end portions of the drive shafts assembled in advance are deviated.
This is one of the factors that hinders assembly into a proper state.

In the bearing, whether the bearing outer ring is press-fitted into the housing or the bearing is press-fitted into the drive shaft is determined by a load. If forcible assembly is performed when the center-to-center distances are different as described above, the inner ring and the outer ring of the bearing will be displaced in the axial direction, the perpendicularity of the drive shaft and the bearing will not be maintained, and the rolling element will have a regular rolling surface. You cannot exercise. This causes non-uniform bearing clearance and eventually deformation of the drive shaft, and the reaction force acts on the bearing when the compressor is assembled. As a result, the bearing life is greatly reduced.

On the other hand, if the two drive shafts are to be kept parallel, the relative positional relationship between the fixed scroll and the orbiting scroll cannot be maintained properly. As a result, there is a possibility that the sealing performance on the side portions of the scroll wrap will be significantly reduced, and conversely, the gap will become small and the sides will come into contact with each other.

This is caused by the fact that the two drive shafts supported at both ends support one rotating body called the orbiting scroll. In other words, one drive shaft is supported by three fixed bearings under conditions that do not impair the linearity of the drive shaft, and the two drive shafts disposed on the outer periphery of the orbiting scroll are connected to each other. This is the fate of the outer peripheral drive type scroll compressor which must be positioned so as to be parallel.

An example of a specific measure for solving the fate of the outer peripheral drive type scroll compressor will be described below with reference to the drawings. FIG. 1 is a front sectional view of an outer peripheral drive type double scroll compressor, and FIG.
The sectional view taken in the direction of the arrow shows the meshing state between the wraps of the fixed scroll members 1 and 2 and the orbiting scroll member 3, and the compression working chamber is formed by the wraps of the fixed scroll members 1 and 2 and the orbiting scroll member 3. It shows the appearance and the like. For convenience of explanation, the drive shafts 4, 5 and the balance weights 17a, 17b, 18a, 1 shown in FIG.
8b and bearings 11a disposed on the orbiting scroll member 3,
11b and the like are all removed from FIG. FIG.
FIG. 2 is an external view showing the front of the compressor of FIG. 1. FIG.
FIG. 4 is an external view showing a side opposite to the side shown in FIG.

In the outer peripheral drive type double scroll compressor shown in FIG. 1, a fixed scroll member 1 having a scroll wrap 1b spirally formed on a mirror plate 1a, and similarly formed on a mirror plate 2a. The fixed scroll member 2 having the scroll wrap 2b is arranged and combined in plane symmetry and parallel to form one casing body 48. In the casing body 48, the orbiting scroll member 3 having scroll wraps 3b and 3c similarly formed in a spiral shape on both surfaces of the end plate portion 3a is included.

A scroll wrap 1b of the fixed scroll member 1 and a scroll wrap 3b of the orbiting scroll member 3,
The scroll wrap 2b of the fixed scroll member 2 and the scroll wrap 3c of the orbiting scroll member 3 mesh with each other to form compression working chambers 14 and 15 on the front and back surfaces of the orbiting scroll member end plate 3a. The scroll wraps 3b and 3c of the orbiting scroll member 3 are
An envelope which has a predetermined thickness and is formed when the orbiting scroll member 3 orbits with a constant radius ε constitutes a basic line of the scroll wrap of the fixed scroll member.

In the scroll portion, the scroll wrap of the orbiting scroll member and the scroll wrap of the fixed scroll member are configured to mesh with each other while maintaining a substantially non-contact state. The compression working chambers 14 and 15 are formed in a crescent shape by both scroll wraps as shown in FIG. In the scroll compressor, such a crescent-shaped compression operation chamber 14 and compression operation chamber 14a are symmetrically formed with respect to a central axis in a pair having substantially the same volume. The compression working chamber 14 reduces its volume while continuously moving to the central part in accordance with the orbital movement of the orbiting scroll member 3.

Tip seals 1c, 2c, 3d made of a composite resin material containing ethylene tetrafluoride resin or polyimide resin as a main component are provided at the tip ends of the wraps of the fixed scroll members 1, 2 and the orbiting scroll member 3, respectively. , 3
e are respectively provided along the spirals. As is clear from FIG. 2, the tip seal 1c is disposed on the wrap tip surface. And it is divided into a plurality in the direction along the spiral. The chip seal may not be divided unless there is a particular problem in function and performance, but the division improves the moldability and assemblability of the chip seal. Furthermore, since the escape of the amount of thermal expansion during the operation of the compressor can be suitably set, the sealing performance and reliability can be improved.

The end plate portion 3a of the orbiting scroll member 3 includes
The communication hole 8 is formed so that the compression operation chambers 14 and 15 on each of the front and back surfaces communicate with each other at a substantially central portion of the end plate 3a at the final stage of operation. On the other hand, as shown in FIGS.
A plurality of suction ports 22 and 23 are formed so as to communicate with the outer peripheral portion of the scroll portion of the fixed scroll member. For example, as shown in FIG. 3, the suction ports 22 and 23 have a flange structure so that suction pipes (not shown) can be connected outside the fixed scroll members 1 and 2 respectively.

The gas sucked in from each of the suction ports 22 and 23 is separated from the outside air in the suction chambers 22a and 23a.
Flows into. The outer space of the scroll wrap 1b of the fixed scroll member 1 is provided with an internal space 19 of the casing body 48.
A dust trap 1f is provided in order to prevent the outside air existing in the air chamber from communicating with the suction chambers 22a and 23a. The dust lap 1f is formed in an annular shape. As shown in FIG. 1, a dust seal 1e similar to the tip seal at the tip of the wrap is fitted into the concave groove on the tip surface of the dust lap 1f. The sealing function is achieved while contacting the end surface of the orbiting scroll member 3.
The stationary scroll member 2 disposed on the opposite side is also provided with a dust wrap 2f and a dust seal 2e. The dust seal 2 e prevents dust in the outside air existing in the internal space 19 of the casing body 48 from flowing into the suction chamber.

A drive shaft 4 having an eccentric portion having an eccentric amount ε and an auxiliary drive shaft 5 having an eccentric portion having the same eccentric amount ε are arranged on the outer peripheral portion of the end plate of the orbiting scroll member 3. The orbiting scroll member 3 is supported by bearings 11a and 11b at the eccentric portions of the drive shafts 4 and 5 so as to be able to orbit. Orbiting scroll member 3 and fixed scroll members 1, 2
In order to absorb the difference in thermal expansion in the direction parallel to the drawing occurring between the drawings and prevent an excessive load from acting on the auxiliary drive shaft 5 and the like,
An elastic support member 13 is provided on the auxiliary drive shaft 5.

The elastic support member 13 is provided on the outer periphery of the bearing 11b. And, it is made of any one of annular resin and rubber, furthermore, engineering plastic and metal spring, or a combination thereof. The orbiting scroll member 3 is supported by two drive shafts so as to be able to orbit. When the drive shafts 4 and 5 are synchronously rotated by the synchronous drive means, for example, the timing belt 7, the orbiting scroll member 3 makes a orbital movement with the eccentric amount ε of the eccentric shaft as a radius in a state where the rotation is prevented. .

By the way, as shown in FIG. 1, a discharge port 9a is formed substantially at the center of the fixed scroll member 1. Further, a radiation fin 1d is provided on an outer surface near the discharge port 9a of the fixed scroll member 1. Like the radiation fin 1d, the radiation fin 2d is formed linearly. Then, in order to obtain a heat exchange amount corresponding to a required heat release amount, it is desirable to divide into a plurality of pieces, or to form a waveform or a substantially rectangular shape. A plurality of ribs 2h are formed on the outer surface of the fixed scroll member where no heat radiation fins are formed to maintain the strength of the fixed scroll member 2. The same applies to the fixed scroll member 1.

The fixed scroll member 1 and the fixed scroll member 2 are fixed on the outer peripheral flange surface while maintaining parallelism with each other, but the two flange heights are greatly different.
The fixed scroll member 1 is lower than the wrap height, while the fixed scroll member 2 is sufficiently higher than the wrap height. When the two fixed scroll members 1 and 2 are combined, a casing body 48 capable of containing the entire orbiting scroll member 3 is formed, and an inner space 19 is formed inside the casing body 48.

On the mirror plate surface 3a of the orbiting scroll member 3,
A plurality of divided cooling air passages 26 are provided by partition walls 31 for cooling the orbiting scroll member 3 with air. A rectangular cooling air passage 26 provided in the orbiting scroll member 3 is disposed so as to face a cooling air vent 28 provided in the upper surface portion of the fixed scroll members 1 and 2 shown in FIG. Flow path cross-sectional area. As a result, the entire cross-section of the passage 26 is reduced to the orbiting scroll member 3.
Irrespective of the swirling motion of the cooling air, the cooling air is always included in the flow path cross section of the ventilation port 28, so that the flow of the cooling air is not hindered. Further, as shown by the arrow 27 in FIG. 2, the cooling air also flows in the internal space 19 of the casing body 48.

The cooling air 27 flows from a cooling air intake 2j (shown in FIG. 4) provided above the fixed scroll member 2 and flows through the inside of the fixed scroll member 2. Dust traps 1f provided on each of the fixed scroll members 1 and 2,
By 2f, the internal space 19 is isolated from the front and back of the orbiting scroll member 3. Therefore, the cooling air 27 is isolated from the compressed suction gas, and is formed around the drive shafts 4 and 5, the bearings, the outer peripheral portion of the orbiting scroll member 3, the inner wall surfaces of the fixed scroll members 1, 2 and the fixed scroll member. The straps 1f and 2f can be cooled. Casing body 4
8. Cooled air inside and end plate 3 of orbiting scroll member
The air flowing through the cooling air passage 26a merges at the lower part of the compressor and flows out from the discharge port 2k to the outside.

A flange 24 is formed on the outer periphery of the fixed scroll member 2. A flange portion 25 is also formed on the outer peripheral portion of the fixed scroll member 1. The pair of fixed scroll members 1 and 2 are connected to each other at the flange portions 24 and 25 by bolts or the like. By the positioning means 16 for adjusting the relative positions of the two fixed scroll members in the X-Y direction and the rotation direction, the relative scroll members 1 and 2 and the orbiting scroll member 3 are properly maintained in relative positional relationship. Thereby, the compression working chambers 14 and 15 suitable for the compression operation are formed, and the orbiting scroll member 3 can smoothly orbit.

The main drive shaft 4 is partially held in the axial direction by a bearing 10a fixed to the fixed scroll member 2. Also, the fixed scroll member 1 has a bearing retainer 41.
The bearing is rotatably supported by the rolling bearing 12a held by the bearing housing 40 fixed by the shaft. The balance weights 17a, 17a are provided on the main drive shaft 4 in order to offset the imbalance caused by the orbiting movement of the orbiting scroll member 3.
b is formed separately or integrally.

The auxiliary drive shaft 5 arranged symmetrically with respect to the main drive shaft 4 is also held in the axial direction by a bearing 10b similarly fixed to the fixed scroll member 2. The other fixed scroll member 1 is rotatably supported by a rolling bearing 12b held by a bearing housing 42 fixed by a bearing retainer 43. Further, the auxiliary drive shaft 5 is also provided with balance weights 18a and 18b for canceling the unbalance due to the orbiting movement of the orbiting scroll member 3.

By assembling the main drive shaft and the auxiliary drive shaft around the bearings as described above, the relative positional relationship between the fixed scrolls 1 and 2 is appropriately assembled using the positioning means 16, and then the bearings 12a and 12b are assembled. Since the bearing can be assembled, the bearing can be assembled in a normal state without imposing an excessive load on the bearing 12. As a result, the applied load acts on the regular rolling surface, and the life of the bearing can be secured.

Since the bearing 12a is fitted into the steel bearing housing 40, the rigidity of the bearing outer ring can be indirectly increased. As a result, even if a large load acts, it is possible to reduce the radial deformation of the outer ring. In addition, the gap between the outer ring and the housing does not change significantly due to thermal expansion during operation, so that the attitude stability of the bearing can be improved, and the reliability of the bearing can be ensured for a long time.

Since the pulley 21 is fixed to the main drive shaft 4 via key means for preventing relative slip, rotational power can be supplied from another power source, for example, an electric motor. Further, toothed pulleys 20a, 20a provided on each shaft so as to maintain the rotational synchronization between the main drive shaft 4 and the auxiliary drive shaft 5.
b and a timing belt 7.

As described above, the fixed scroll member 1,
The orbiting scroll member 3 and the orbiting scroll member 3 are each made of a light material having good heat conductivity as represented by an aluminum alloy or the like. Then, in order to obtain an oil-free compressor, it is particularly preferable to apply an aluminum alloy containing silicon. To improve the lubricity when contacting the wrap, or to increase the reliability against seizure during contact, the anodic oxide coating treatment that is almost entirely compatible with aluminum alloys, such as the side surfaces of the scroll wrap and the end plate surface It is desirable to apply a surface treatment such as In addition, supporting feet 1i and 2i are provided at the lower part of the compressor, and the compressor can be fixed in a stable state.

Next, the operation of the embodiment constructed as described above will be described. When electric power is supplied to the electric motor, power is transmitted to the compressor pulley 21. As a result, the main drive shaft 4 rotates, and at the same time, the auxiliary drive shaft 5 connected by the timing belt 7 rotates. The orbiting scroll member 3 supported by the drive units of the two drive shafts 4 and 5 makes a revolving motion having a radius equal to the amount of eccentricity ε of the drive shafts 4 and 5 in a state where rotation is prevented. With the movement of the orbiting scroll member 3, air is drawn from the suction chambers 22a, 22
3a. The inflowing air is supplied to the compression working chamber 14,
Compressed to a predetermined pressure while reducing the volume in 15.
The high-pressure air is maintained at substantially the same pressure by a communication hole 8 provided in the end plate portion of the orbiting scroll member, and is supplied to a demand source from discharge ports 9a and 9b provided in both fixed scroll members.

During the compression operation, the gas in the compression working chambers 14 and 15 on each of the front and back surfaces of the head plate is balanced in pressure, so that the sum of the thrust forces of the compressed gas is substantially equal. For this reason, the orbiting scroll member 3 is fixed to the fixed scroll members 1, 2
, And no large thrust load acts on the tip surface of the wrap. Therefore, the sliding loss at the wrap tip can be reduced. Further, the wear amount of the tip seal can be reduced.

Since the pressure is substantially equal at the center of each fixed scroll member, the communication hole 8 at the center of the end plate portion of the orbiting scroll member may be omitted when the compressor capacity is small. Further, the number of the discharge ports may be any one of the discharge port 9a and the discharge port 9b, and the diameter of the communication hole 8 may be increased.

The inner and outer surfaces of the fixed scroll members 1 and 2 and the orbiting scroll member 3 are simultaneously cooled by the cooling air of the compressor, so that the amount of heat generated due to the compression can be appropriately removed. As a result, since each scroll member is maintained at an appropriate temperature, the amount of thermal expansion can be controlled, and the gap between the scroll wraps can be kept in a non-contact and small amount during the operation of the compressor. .

Next, details of the elastic body used in the scroll compressor shown in FIG. 1 will be described with reference to FIGS. FIG. 5 is a detailed view around the bearing that holds the main drive shaft 4 held by the fixed scroll 1 member. One fixed scroll member has two bearing portions corresponding to the drive shaft 4 and the auxiliary drive shaft 5. In this drawing, taking into account that these two bearing portions have almost the same configuration, the main drive shaft 4
3 shows a bearing portion of the present invention.

The bearing housing 40 made of a steel material is fixed to the end plate 1a of the fixed scroll 1 made of an aluminum alloy together with the bearing retainer 41 with bolts 44. The rolling bearing 12a is pressed into the main drive shaft 4 on the inner ring side. The main drive shaft 4 is formed with a shoulder 4a.
2a is positioned. The bearing outer ring is a bearing housing 4
0 is fitted with a minute gap. An elastic body 45 is mounted between the bearing outer ring and the bearing retainer 41 to regulate the axial position of the bearing. The elastic body 45 is
An annular corrugated leaf spring or a ring-shaped polymer material.

When the bearing portion is configured as described above, after assembling the fixed scroll 1 and the fixed scroll, the bearing 12a can be assembled to the drive shaft 4 while adjusting the gap alone. Therefore, the perpendicularity between the drive shaft and the bearing can be maintained with high accuracy. Further, the position of the bearing in the thrust direction is regulated by the elastic body 45. However, since the load in the thrust direction of the bearing is determined by this elastic force, an excessive load can be prevented from acting on the bearing.
It is possible to extend the bearing life.

Next, another example of the bearing used in the compressor shown in FIG. 1 is shown in FIG. In this example, a bearing housing 40 is provided with a bearing holding portion 40a. In this example, similarly to the example of FIG. 5, the bearing part can be attached after assembling the scroll components. By providing the bearing holding portion 40a, the positioning of the bearing 12a in the thrust direction can be performed more reliably. Therefore, the reliability of the bearing is increased, and the compressor can be operated for a long time.

FIG. 7 shows still another example of the bearing used in the compressor shown in FIG. The point that the elastic body 45 is provided in the thrust direction of the bearing is the same as the example shown in FIG. 5, but in this example, the elastic body 46 is arranged also in the radial gap between the bearing outer ring and the bearing housing 40. I have. Then, the elastic body 46 is crushed by the protrusion 41 a of the bearing retainer 41. At this time, the elastic body 46 is also crushed in the radial direction. Elastic body 4
6 is preferably an O-ring or the like.

With this configuration, the gap between the bearing outer race and the bearing housing 40 can be partially filled, and positioning in the radial direction can be performed accurately. Further, a relative slip phenomenon, that is, creep, occurring between the bearing outer ring and the bearing housing 40 can be prevented beforehand, and the reliability of the bearing can be increased.

FIG. 8 shows still another example of the bearing used in the compressor shown in FIG. In this example, a pin 49 is attached to the bearing outer ring.
And the pin 49 is engaged with the bearing housing 40. The pin 49 regulates the movement of the bearing in the rotation direction,
There is a degree of freedom for movement in the thrust and radial directions. With this pin, even if there is a minute gap between the bearing housing 40 and the bearing outer ring, creep generated between the bearing outer ring and the bearing housing 40 can be prevented beforehand.

FIGS. 9 and 10 show still another example of the bearing used in the compressor shown in FIG. In this example, the bearing housing 40 is so-called cast-in for the fixed scroll 1a. This is the fixed scroll 1a
Is an aluminum alloy casting, a bearing housing material made of an iron-based material is combined with a fixed scroll and arranged at a predetermined position to produce the bearing housing material. As shown in FIG. 10, the bearing housing 40 has a convex portion 40b on the circumference.
And a recess 40c are formed. By doing so, the fixed scroll 1a and the bearing housing 40 can be integrated.
It is also possible to fix at 0. Further, since the inner surface of the bearing housing 40 can be finished at the time of processing the fixed scroll 1a, the gap between the outer ring of the bearing and the inner surface of the bearing housing 40 can be suitably set. According to this example, the stability of the position of the bearing housing 40 with respect to the fixed scroll 1a is increased, and the stability of the bearing posture can be ensured even with a larger bearing load.

According to each of the above embodiments, when assembling the compressor body, the effects of misalignment due to machining tolerances and component precision are reduced, especially for bearings provided on the fixed scroll located on the opposite side of the pulley. And the rigidity of the bearing outer ring can be increased. Further, the gap between the bearing outer ring and the bearing housing can be maintained at the set gap. Further, by reducing the thrust force acting on the bearing or keeping it substantially constant, the posture stability of the bearing can be improved. Further, since relative slip between the outer race and the bearing housing can be reduced or avoided, the life of the bearing can be improved. Thus, the outer peripheral drive type double scroll compressor can be stably operated for a long time.

[0052]

According to the present invention, since the cumulative machining error of the compressor and the influence of thermal deformation during operation can be reduced, the outer peripheral drive type double scroll compressor can be stably operated for a long period of time.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a double scroll compressor according to the present invention.

FIG. 2 is a front view as viewed in the direction of arrows AA in which the orbiting scroll member and the fixed scroll member used in the compressor shown in FIG. 1 are combined.

FIG. 3 is a front external view of the compressor shown in FIG.

FIG. 4 is a rear external view of the compressor shown in FIG.

FIG. 5 is a sectional view showing details of a bearing used in FIG. 1;

FIG. 6 is a sectional view showing details of another example of the bearing used in FIG. 1;

FIG. 7 is a sectional view showing details of still another example of the bearing used in FIG. 1;

FIG. 8 is a sectional view showing details of still another example of the bearing used in FIG. 1;

FIG. 9 is a sectional view showing details of still another example of the bearing used in FIG. 1;

FIG. 10 is a front view of an example of the bearing housing used in FIG. 1;

[Explanation of symbols]

1, 2, ... fixed scroll member, 1a, 2a ... fixed scroll head, 1b, 2b ... scroll wrap, 1
c, 2c ... chip seal, 1d, 2d ... radiation fin, 1e, 2e ... dust seal, 1f, 2f ... dust strap, 1h, 2h ... rib, 1i, 2i ... support foot, 3 ... Orbiting scroll member, 3a ... end plate part, 3
b, 3c scroll wrap, 3d, 3e tip seal, 4 main drive shaft, 5 auxiliary drive shaft, 7 timing belt, 8 communication hole, 9a, 9b discharge port, 10a, 10b ... bearing, 11a, 11b ... bearing, 12a, 12b ... bearing, 13 ... elastic support member,
14, 15 ... compression working chamber, 16 ... positioning means, 1
7a, 17b ... balance weight, 18a, 18b ...
... balance weight, 19 ... internal space, 20a, 20
b: toothed pulley, 21: pulley, 22, 23 ... suction port, 22a, 23a ... suction chamber, 24, 25 ... flange part, 28, 29 ... cooling air vent, 40, 42
... bearing housing, 41, 43 ... bearing retainer, 45
... elastic body, 46 ... elastic body, 48 ... casing body.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kazuaki Shiiki 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture Within Hitachi Industrial Equipment Group (72) Inventor Natsuki Kawabata 390 Muramatsu, Shimizu-shi, Shizuoka Industrial Equipment Hitachi, Ltd. Within the Group (72) Inventor Isamu Kawano 390 Muramatsu, Shimizu-shi, Shizuoka Prefecture F-term in the Industrial Equipment Group, Hitachi, Ltd.

Claims (8)

[Claims] 1. An orbiting scroll having a pair of fixed scrolls formed with spiral wraps and wraps meshing with the wraps formed on both sides of an end plate, wherein an outer peripheral portion of the orbiting scrolls is driven via bearing means. In the outer peripheral drive type double scroll compressor having a main drive shaft and an auxiliary drive shaft, at least one of the pair of fixed scrolls,
An outer peripheral drive type double scroll compressor, comprising a bearing housing for holding the bearing means separate from the fixed scroll. 2. An outer peripheral drive type double scroll compressor according to claim 1, wherein said fixed scroll is made of an aluminum alloy and said bearing housing is made of an iron-based metal. 3. The bearing means has a rolling bearing,
2. The outer peripheral drive type double scroll compressor according to claim 1, wherein a minute gap is formed between the inner surface of the bearing housing and the outer ring of the rolling bearing during assembly. 4. The outer peripheral drive type double scroll compressor according to claim 1, wherein the inner diameter of the bearing housing is smaller on the scroll wrap surface side than on the opposite surface side. 5. The bearing means has a rolling bearing and a bearing retainer for holding the rolling bearing. An elastic body is mounted between an outer ring of the rolling bearing and an inner surface of the bearing housing, and the bearing retainer and the rolling bearing are provided. The bearing is arranged so that the elastic body can change its volume.
4. The outer peripheral drive type double scroll compressor according to any one of 1 to 3. 6. The bearing means has a rolling bearing and a bearing retainer. The rolling bearing is press-fitted into at least one of the main drive shaft and the auxiliary drive shaft, and has a clearance fit with the bearing housing. 4. The outer peripheral drive type double scroll compressor according to claim 1, wherein an elastic body is interposed between the bearing retainer and an outer ring of the rolling bearing. 7. The bearing device according to claim 1, wherein said bearing means includes a rolling bearing, and a pin which engages with both an outer ring of said rolling bearing and said bearing housing. An outer peripheral drive type double scroll compressor as described in the above. 8. The fixed scroll is made of an aluminum alloy, the bearing housing is made of steel, and the aluminum alloy fixed scroll and a steel bearing housing are integrated by casting. 4. The outer peripheral drive type double scroll compressor according to any one of items 3 to 3.