JPH04334701A - Scroll fluid machine - Google Patents

Abstract

PURPOSE:To improve scroll member slide contact portion sealing and lubricating properties by providing at a movable scroll member an oil supply passage whose tip faces the refrigerant gas suction opening of compression chambers formed by movable and fixed scroll members and at the same time whose other end opens at an oil passage. CONSTITUTION:At a scroll fluid machine 1, refrigerant gas is sucked into a suction pressure chamber 28 through a suction hole 32 and a suction opening 32, and compressed in order at a middle pressure chamber 29 and a discharge pressure chamber 30, and discharged from a discharge port 34 through a discharge pipe 37. On the other hand, oil lubricates radial bearings 22, 11 and a thrust bearing 44 through the opening of a fitting in recessed portion 8 and an oil hole 43. And at the same time oil runs to an oil supply passage 47, and the supply of oil is made from the upper part opening. As oil different from oil lubricating a bearing portion is supplied to the suction pressure chamber, oil temperature becoming high is prevented, and oil viscosity lowering is eliminated.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a closed scroll fluid machine used in air conditioners, refrigeration equipment, etc.

0002

2. Description of the Related Art A conventional scroll fluid machine is known, for example, as described in Japanese Unexamined Patent Publication No. 106392/1983. In this type of scroll fluid machine, a movable scroll member is connected to the upper end of the drive shaft of an electric motor eccentrically with respect to the drive shaft axis, and the movable scroll member moves eccentrically as the drive shaft rotates. The refrigerant gas is compressed in a plurality of compression chambers formed between the fixed scroll member and the fixed scroll member fixed to the refrigerant gas.

[0003] Furthermore, an oil pump is attached to the lower end of the drive shaft, and the oil sucked up by this oil pump passes through the oil passage formed in the drive shaft to the radial bearing and thrust bearing of the drive shaft. After being lubricated and cooled, the refrigerant gas is sucked into the compression chamber formed by both scroll members, and the sliding portions of both scroll members are sealed and lubricated.

0004

However, according to the above-mentioned conventional scroll fluid machine, the oil sucked up by the oil pump is once supplied to each bearing portion and then supplied to the compression chamber. There was a problem in that it was difficult to reliably seal, lubricate, and cool the sliding contact portion of the scroll member.

In other words, the temperature of the oil flowing to each bearing increases due to frictional heat, and the viscosity of the oil decreases.When such high-temperature oil is supplied to the compression chamber, both At the same time, the sealing performance of the sliding portions of the scroll members deteriorates, and lubrication failure also occurs, which may result in a reduction in refrigerating capacity and seizure in the sliding portions of both scroll members.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a scroll fluid machine that can improve the sealing performance and lubricity of the sliding portions of both scroll members and increase the refrigerating capacity.

[0007]

[Means for Solving the Problems] The scroll fluid machine of the present invention includes a drive shaft of an electric motor that is rotatably supported by a support block, and a drive shaft that is eccentrically connected to the drive shaft and that moves eccentrically with respect to the axis of the drive shaft. A scroll fluid machine comprising a movable scroll member, a fixed scroll member fixed to mesh with the movable scroll member, and an oil passage that guides oil sucked up by an oil pump to a bearing portion, the scroll fluid machine comprising: The movable scroll member is provided with an oil supply passage whose tip faces the refrigerant gas inlet of the compression chamber formed by both scroll members and whose other end opens into the oil passage.

[0008]

[Operation] By providing an oil supply passage separate from the oil passage that lubricates the bearing, oil that is cold and has a predetermined viscosity is supplied into the compression chamber.
The sealing properties and lubricity of the sliding contact portions of both scroll members are improved, and the refrigeration capacity can be increased.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a scroll fluid machine 1, and FIG. 2 shows its scroll portion. In the figure, 2 is a closed case, and this case 2 includes a cylindrical part 3 and upper and lower closed parts 4.
and 5.

A brushless DC motor 7 is disposed at the bottom of the case 2. That is, a drive shaft 8 of the electric motor 7 is disposed vertically within the case 2 , and a lower portion of the drive shaft 8 is supported by the case 2 via a radial bearing 9 . The upper part of the drive shaft 8 is supported by a support block 10 fixed to the case 2 via a radial bearing 11. A columnar rotor 1 made of a laminated iron core is mounted on the lower end side of the drive shaft 8.
A permanent magnet 13 is attached to the circumferential surface of the rotor 12, and the permanent magnet 13 has N poles and S poles arranged alternately. A cylindrical stator 14 is fixed to the case 2 around the permanent magnet 13. This stator 14 is formed of a laminated iron core, and each salient pole portion of the stator 14 has an exciting coil 1.
6 are each wound. Note that 17 in the figure indicates a connector to which the lead wire 18 of the excitation coil 16 is connected.

A suction pipe 19 is attached to the center of the case 2, and refrigerant gas is sucked through the pipe 19 and flows as shown by the solid arrow in the figure.

The upper end side of the drive shaft 8 is formed to have a large diameter,
A fitting recess 8b is formed within this large diameter portion 8a. The center O2 of the fitting recess 8b is provided eccentrically from the center O1 of the drive shaft 8 by a predetermined dimension. A connecting insertion portion 21a protruding from the back surface of the movable scroll member 21 is inserted into the fitting recess 8b via a radial bearing 22. Therefore, as the drive shaft 8 rotates, the connecting insertion portion 21a moves eccentrically, and the movable scroll member 21 is driven to rotate. Further, since the movable scroll member 21 is driven to rotate, balance weights 23 and 24 are attached to the drive shaft 8 in order to stabilize the rotational balance of the drive shaft 8.

Furthermore, an Oldham ring 25 is interposed between the support block 10 and the movable scroll member 21 to prevent the movable scroll member 21 from rotating when the movable scroll member 21 is driven to rotate.

The movable scroll member 21 is engaged with a fixed scroll member 27 fixed to the support block 10 via a shim plate 48, and both scroll members 21 and 27 compress the suction pressure chamber 28 to an intermediate pressure. An intermediate pressure chamber 29 is compressed to a high pressure of the discharge pressure, and a discharge pressure chamber 3 is compressed to a high pressure of the discharge pressure.
0 is formed. The support block 10 is provided with suction holes 32 spaced apart in the circumferential direction that communicate with the suction pipe 19, and suction ports 33 that communicate with each of these suction holes 32 and communicate with the suction pressure chamber 28 are provided with shims. It is provided on the plate 48. The refrigerant gas introduced from the suction pipe 19 is supplied to each suction pressure chamber 28 through each suction hole 32 and suction port 33. Further, a discharge port 34 communicating with the discharge pressure chamber 30 is formed in the center of the fixed scroll member 27, and a reed valve 35 is provided in the discharge port 34. A support member 36 that covers the reed valve 35 is attached to the upper surface side of the fixed scroll member 27, and a discharge pipe 37 is attached to this support member 36, so that the high-pressure refrigerant gas in the discharge pressure chamber 30 is delivered to the discharge port 34 and the reed valve 35. It is discharged to the discharge pipe 37 through the discharge pipe 37.

Furthermore, an oil passage 40 is formed in the axial center of the drive shaft 8, and an oil pump (trochoid pump) 42 is provided at the lower end of the drive shaft 8 to suck up oil from an oil reservoir 41 into the oil passage 40. is provided. The upper end side of this oil passage 40 is opened at the fitting recess 8b,
The radial bearing 22 is lubricated through the gap in the recess 8b, and the radial bearing 11 and the thrust bearing 44 are lubricated through the oil hole 43 provided in the large diameter portion 8a of the drive shaft 8. Further, a return oil passage 45 is formed in the support block 10 so that the oil that has lubricated the radial bearings 22, 11 and the thrust bearing 44 can return to the oil reservoir 41 through the return oil passage 45.

Furthermore, the connecting insertion portion 21a of the movable scroll member 21 has one end communicating with the oil passage 40 via a vertical fitting gap, and the other end opening into the suction port 33 of the movable scroll member 21. An oil supply passage 47 is formed.

In such a scroll fluid machine 1, refrigerant gas flows from the suction pipe 19 to the suction hole 32 and the suction port 33.
The air is sucked into the suction pressure chamber 28 through the air, is sequentially compressed in the intermediate pressure chamber 29 and the discharge pressure chamber 30, and is discharged from the discharge port 34 through the discharge pipe 37.

On the other hand, the oil sucked up by the oil pump 42 lubricates the radial bearings 22 and 11 from the oil passage 40 through the gap in the fitting recess 8b and the oil hole 43, then lubricates the thrust bearing 44, and returns oil. It returns to the oil sump 41 via a passage 45. At the same time, the oil in the oil passage 40 reaches the oil supply passage 47 through the gap, and is supplied from the opening at the top. In this case, the intake port 33
The refrigerant gas sucked into the refrigerant gas is mixed with the refrigerant gas by an atomizing action and supplied to the suction pressure chamber 28.

Therefore, since oil different from the oil that lubricates the bearings is supplied to the suction pressure chambers, the oil does not reach a high temperature, and as a result, the oil viscosity does not decrease and each compression chamber It is possible to improve the sealing performance and increase the refrigerating capacity, and also to ensure the lubrication of each sliding part of both scroll members, thereby preventing the occurrence of seizure.

Next, a second embodiment of the present invention will be described. In this embodiment, as shown in FIGS. 3 and 4, a valve 50 for adjusting the oil supply amount is installed in the middle of the oil supply passage 47.
It is an intervening one. This valve 50 is connected to the suction pressure chamber 2.
The amount of oil supplied to oil pump (drive shaft) 4
Since the amount of oil in the oil reservoir 41 becomes insufficient at high rotation speeds, the oil reservoir 41 is provided so as to be able to limit the amount of oil at high rotation speeds to prevent this.

That is, as shown in FIG. 5, this valve 50 is provided in a cylindrical valve chamber 21b formed in the connecting insertion portion 21a. The valve 50 consists of a large diameter part 50A and a small diameter part 50B, the large diameter part 50A is formed in a size that can be slid into the valve chamber 21b, and the small diameter part 50B is protruded from the upper part of the large diameter part 50A. There is. The large diameter portion 50A also includes an oil passage 5 that communicates with an opening 21c provided at the bottom of the valve chamber 21b of the connecting insertion portion 21a.
1 are provided in the radial direction as shown in FIG. 6, and during low rotation, oil flows into the oil supply passage 47 through the opening 21c, the oil passage 51, and the valve chamber 21b as shown by the arrow in FIG.

[0022] Also, in the small diameter portion 50B, a throttle oil passage 5 is provided.
2 is formed in the axial direction, and the tip of the small diameter portion is formed into a tapered inclined surface, and the opening of the oil supply passage 47 can be closed by this inclined surface. During high rotation, the valve 50 is lifted as shown in FIG. 7 due to the differential pressure between the oil on the upstream side and the downstream side of the valve 50 in the valve chamber 21b, and the inclined surface of the small diameter portion 50B causes the oil supply passage 47 to
When the opening is closed, oil is supplied through the throttle oil passage 52. Note that the valve is made of metal, plastic, or the like.

In the case of the second embodiment, the same effects as those of the previous embodiment can be obtained, and when the rotation reaches a predetermined high speed or higher,
Since oil will be supplied only from the throttle oil passage,
It is possible to reduce the increase in the amount of oil discharged from the scroll fluid machine along with the refrigerant gas, and there is no shortage of oil in the oil reservoir even at high rotations, preventing seizure on the sliding parts of both scroll members. can be reliably prevented.

[0024]

[Effects of the Invention] As explained above, according to the present invention,
By providing an oil supply passage separate from the oil passage that lubricates the bearing, cold oil with a predetermined viscosity can be supplied to the compression chamber, improving the sealing and lubricity of the sliding parts of both scroll members. , it is possible to improve the refrigerating capacity and prevent seizure of the sliding parts.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a scroll fluid machine according to a first embodiment of the present invention.

FIG. 2 is a longitudinal cross-sectional view of a scroll portion of the scroll fluid machine shown in FIG. 1 according to a first embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of a scroll fluid machine according to a second embodiment of the present invention.

FIG. 4 is a longitudinal cross-sectional view of a scroll portion of the scroll fluid machine shown in FIG. 3, according to a second embodiment of the present invention.

5 is a longitudinal section of a valve according to a second embodiment of the present invention, and is a sectional view taken along the line V-V in FIG. 6. FIG.

6 is a sectional view taken along the line VI-VI in FIG. 5, showing a cross section of a valve according to a second embodiment of the present invention; FIG.

FIG. 7 is a longitudinal cross-sectional view showing valve operation at high rotation speed according to a second embodiment of the present invention.

[Explanation of symbols]

1 Scroll fluid machine 2 Case 7 Electric motor 8 Drive shaft 10 Support block 11, 22, 44 Bearing part 21 Movable scroll member 28, 29, 30 Compression chamber 27 Fixed scroll member 33 Refrigerant gas inlet 40 Oil passage 42 Oil pump 47 Oil supply passage

Claims (1)

[Claims] 1. A drive shaft of an electric motor rotatably supported by a support block; a movable scroll member eccentrically connected to the drive shaft and moving eccentrically with respect to the axis of the drive shaft;
In a scroll fluid machine including a fixed scroll member fixed to mesh with the movable scroll member, and an oil passage that guides oil sucked up by an oil pump to a bearing portion, the movable scroll member has a tip end thereof. A scroll fluid machine characterized in that an oil supply passage is provided which faces a refrigerant gas inlet of a compression chamber formed by both of the scroll members and whose other end opens into the oil passage.