JPH051501A - Scroll type fluid machine - Google Patents

Abstract

PURPOSE:To prevent excessive oil infection to a fluid actuation chamber so as to avoid oil compression, and maintain a sealability in the actuation chamber good in a simple structure without using a capillary tube. CONSTITUTION:A bottom part of an oil sump 97 is opened in a shaft bearing part 5 for supporting a crank shaft 93 through a supply oil passage 5, an oil groove 51 extending along the shaft in the inner surface of the shaft bearing part 5 is provided, the oil groove 51 is connected with a fluid actuation chamber 4 in a middle pressure zone through an oil injection passage 7, and the oil sump 97 at a high pressure is connected with the fluid actuation chamber 4 at a middle pressure through a small bearing gap at the bearing part 5, thereby an injection oil quantity to the fluid actuation chamber 4 is limited.

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 in which oil is injected into a fluid working chamber for compressing a refrigerant to seal the fluid working chamber.

[0002]

2. Description of the Related Art Conventionally, as disclosed in, for example, Japanese Patent Laid-Open No. 3-88988 and shown in FIG. 3, a fixed scroll A and a movable scroll B each having a spiral casing a and b in a high-pressure dome-shaped hermetic casing D are provided. And a low pressure gas which is taken into the outer periphery of the spiral through the suction pipe L is compressed in the fluid working chamber C defined between the spiral bodies a and b, and the high pressure gas after compression is provided at the center of the spiral. It is designed to open from H to the inside of the closed casing D. Then, in order to seal the inside of the fluid working chamber C and maintain its airtightness, an oil injection pipe extending from the bottom oil reservoir of the closed casing D in the high pressure atmosphere to the working chamber C in the intermediate pressure region during compression. J is connected and oil is injected by differential pressure, and each spiral body a, b
An oil film necessary for sealing can be formed on the sliding contact surface between them.

[0003]

However, in the above, since the high-pressure oil reservoir and the fluid working chamber C at the intermediate pressure are communicated with each other through the oil injection pipe J, these high-pressure oil reservoir and the intermediate fluid working chamber C are connected to each other. Since it is necessary to prevent an excessive amount of oil to be injected based on the pressure difference between the fluid working chamber C and the fluid working chamber C, and to prevent abnormally high pressure due to oil compression or the like in the fluid working chamber C, Since it is necessary to configure the oil injection pipe J with a small-diameter capillary tube to limit the flow rate, there is a problem that the cost becomes high and a space is required for turning the pipe and the like, and moreover, foreign matter is contained in the small-diameter pipe. That is, it is easy, and there is a problem that a special filter or the like is required to avoid this.

In the present invention, the small gap in the bearing portion that supports the rotating portion is utilized, and the pressure reducing function of the oil injection passage due to the differential pressure is provided in this portion, so that the capillary tube is eliminated and the fluid operation can be performed easily and satisfactorily. An object of the present invention is to provide a scroll type fluid machine capable of sealing a room.

[0005]

Therefore, in order to achieve the above object, the present invention has a high-pressure dome-shaped hermetic casing 1.
In a scroll type fluid machine in which a fixed scroll 2 and a movable scroll 3 are internally provided, and a fluid working chamber 4 is defined between scrolls of these scrolls 2, 3, a casing 5 is provided in a bearing portion 5 supporting a rotating portion. An oil supply passage 6 extending from an oil reservoir provided inside is opened, and an oil outlet side of the bearing portion 5 and the fluid working chamber 4 are communicated with each other via an oil injection passage 7.

Further, with the above construction, it is preferable that an oil groove 51 is provided on the sliding surface of the bearing portion 5, and the starting end portion of the oil injection passage 7 is opened in this oil groove 51.

[0007]

The high pressure oil reservoir provided inside the closed casing 1 and the fluid working chamber 4 whose pressure is lower than this are connected via the oil supply passage 6, the bearing portion 5 and the oil injection passage 7 to provide oil. Oil is supplied from the reservoir to the bearing portion 5 through the oil supply passage 6, and the bearing portion 5 can be lubricated, and the oil after lubricating the bearing portion 5 passes through the oil injection passage 7 and enters the fluid working chamber 4. And the inside of the fluid working chamber 4 can be sealed. Since the high-pressure oil reservoir and the fluid working chamber 4 having a lower pressure than this are connected through a small bearing gap of the bearing portion 5, the passage is throttled by the bearing portion 5 to perform a predetermined decompression. It is possible to prevent excessive lubrication of the fluid working chamber 4 without providing a capillary tube.

Further, an oil groove 51 is provided on the sliding surface of the bearing portion 5,
By opening the starting end portion of the oil injection passage 7 in the oil groove 51, it is possible to avoid extremely limiting the amount of oil in the bearing portion 5, and collect oil in the oil groove 51 so that the oil injection passage 7 side Can supply oil well.

[0009]

EXAMPLE A scroll type fluid machine shown in FIG.
1. A fixed scroll 2 in which a spiral body 22 and an outer peripheral wall 23 continuous with the spiral body 22 are projectingly provided on an end plate 21 at a lower portion of a high-pressure dome-shaped hermetic casing 1 including a top 1, a top 12, and a bottom 13.
And the movable scroll 3 in which the scroll 32 is projected on the end plate 31.
And a motor 9 having a rotor 91 and a stator 92 on the upper part thereof.

An eccentric hole 94 is provided in the lower portion of the crankshaft 93 connected to the rotor 91, and the eccentric hole 94 is
A boss portion 33 protruding from the back surface of the movable scroll 3 is fitted, and an Oldham ring 30 that prevents rotation of the movable scroll 3 is interposed between the movable scroll 3 and the housing 8 and is driven by a motor 9. The scroll 3 is revolved and the low-pressure gas taken in from the suction pipe 14 is passed through the scrolls 22, 3
2 is compressed in the fluid working chamber 4 and the compressed high pressure gas is discharged from the discharge hole 34 opening to the center of the scroll of the movable scroll 3 and the inclined communication hole 95 provided in the crankshaft 93 to the closed casing 1. It is opened inside and the upper discharge pipe 15
I take it out from the outside.

In the above construction, the cylindrical partition 9 surrounding the outer peripheral side of the crankshaft 93 is provided on the upper surface of the housing 8.
6 is attached, an annular oil sump 97 is provided on the outer side thereof, and the bottom of this oil sump 97 is opened to the bearing portion 5 that supports the crankshaft 93 via the inclined oil supply passage 6 provided in the housing 8. To do. By the way, a ring body 80 is provided on the back surface of the movable scroll 3, and a high pressure side working chamber 81 is provided on the inner peripheral side.
Low pressure side working chambers 82 are defined on the outer peripheral side, and the outlet of the oil supply passage 6 is opened to the high pressure side working chamber 81 via the interposition groove 83 of the ring body 80. From the side working chamber 81 to the bearing 5 and the movable scroll 3
The fitting portions of the boss portion 33 and the eccentric hole 94 can be lubricated respectively.

An oil groove 51 extending axially over a predetermined length is provided on the inner surface of the bearing portion 5.
1 and the fluid working chamber 4 in the intermediate pressure region in the middle of the compression stroke are communicated via the oil injection passage 7. The oil injection passage 7 is defined inside the bottom 13 through a horizontal hole 71 that opens the oil groove 51 in the radial direction, a horizontal hole 72 and a vertical hole 73 provided in the housing 8, and a vertical hole 74 provided in the fixed scroll 2. It is opened in the chamber 75 and is connected to a pair of oil injection ports 77, 77 provided in the fixed scroll 3 via a pair of pipes 76, 76 for sucking oil from the bottom side of the chamber 75. It should be noted that the oil groove 51 collects the oil, which has been supplied to the fitting portion between the boss portion 33 of the movable scroll 3 and the eccentric hole 94, through the inclined oil hole 98 provided in the crankshaft 93. In addition, the oil hole 98 and the discharge hole 34
The seal ring 35 provided between the bottom of the fitting portion and the communication hole 95.

In this way, the high pressure oil reservoir 97 and the fluid working chamber 4 in the intermediate pressure region are connected through the oil supply passage 6, the bearing portion 5 and the oil injection passage 7, and the oil reservoir 97 is connected to the oil supply passage 6. Oil is supplied to the bearing portion 5 via the oil, and the bearing portion 5 can be lubricated, and the oil after lubricating the bearing portion 5 passes through the oil injection passage 7 and the fluid working chamber 4
The inside of the fluid working chamber 4 can be sealed by the injection. Since the high pressure oil reservoir 97 and the fluid working chamber 4 at the intermediate pressure are connected through the small bearing gap of the bearing portion 5, the passage is throttled by the bearing portion 5 to perform a predetermined decompression. ,
Fluid working chamber 4 without providing a capillary tube
It is possible to prevent excessive oiling. Further, since the small gap of the bearing portion 5 which performs the pressure reducing action is always in contact with the crankshaft 93 which is the rotating portion, there is almost no possibility of clogging or the like occurring in the gap portion.

In addition, since the oil groove 51 is provided in the bearing portion 5 and the end of the oil injection passage 7 is opened in the oil groove 51, it is possible to avoid a situation where the oil amount is extremely limited in the bearing portion 5. It is possible to collect the oil in the oil groove 51 and supply the oil well to the oil injection passage 7 side.

In the embodiment shown in FIG. 1, the scrolls 2 and 3 are arranged in the lower portion, but as shown in FIG. 2, the scrolls 2 and 3 are arranged in the upper portion of the closed casing 1. It is also applicable to.

That is, in the structure shown in FIG. 2, the bottom of the closed casing 1 is provided with an oil reservoir, and the oil reservoir 61 provided in the crankshaft 93 and the boss portion 33 of the movable scroll 3 are provided from this oil reservoir at the bottom. Oil is released into the high-pressure side working chamber 81 on the inner peripheral rear surface side of the movable scroll 3 through the oil supply passage 6 formed of the axial hole 62 and the radial hole 63, and the high-pressure side working chamber 81 moves to the crankshaft 93. Oil is supplied to the fitting portion between the bearing portion 5 and the boss portion 33 of the movable scroll 3 and the eccentric hole 94, and an oil groove 51 is provided on the outer peripheral portion of the crankshaft 93 that is in contact with the bearing portion 5. The oil injection passage 7 is opened, and its outlet side is connected to the respective oil injection ports 77, 77 through lateral holes 78 extending laterally without communicating with the back side of the fixed scroll 2. The discharge gas is released from the discharge hole 24 opening in the center of the fixed scroll 2 to the inside of the closed casing 1 through the chamber 16 on the top 12 side, and taken out to the outside from the discharge pipe 15 connected to the side portion. I am trying.

Also in the one shown in FIG. 2, as in the above, the fluid working chamber 3 is properly operated without using a capillary tube.
Oil can be injected into it.

[0018]

As described above, according to the present invention, it is possible to prevent an excessive amount of oil to be injected into the fluid working chamber 4 with a simple structure using the bearing portion 5 without using a capillary tube. It is possible to prevent abnormal high pressure from being generated in the working chamber 4 due to oil compression and the like, and it is possible to maintain good sealing performance in the working chamber 4.

Further, an oil groove 51 is provided on the sliding surface of the bearing portion 5,
By opening the starting end portion of the oil injection passage 7 in the oil groove 51, it is possible to avoid extremely limiting the amount of oil in the bearing portion 5, and collect oil in the oil groove 51 so that the oil injection passage 7 side It is also possible to supply oil well.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a scroll type fluid machine of the present invention.

FIG. 2 is a sectional view showing the second embodiment.

FIG. 3 is a sectional view of a conventional scroll type fluid machine.

[Explanation of symbols]

1 closed casing 2 fixed scroll 3 Movable scroll 4 Fluid working chamber 5 Bearing part 6 oil supply passage 7 oil injection passage 51 oil ditch

Claims (2)

[Claims] 1. A scroll type fluid machine in which a fixed scroll 2 and a movable scroll 3 are provided in a high-pressure dome type closed casing 1 and a fluid working chamber 4 is defined between scrolls of the scrolls 2 and 3. An oil supply passage 6 extending from an oil reservoir provided inside the casing 1 is opened in a bearing portion 5 supporting the portion, and an oil injection portion between the oil outlet side of the bearing portion 5 and the fluid working chamber 4 is injected. A scroll type fluid machine characterized by being communicated with each other through a passage 7. 2. A scroll type fluid machine according to claim 1, wherein an oil groove 51 is provided on a sliding surface of the bearing portion 5, and a starting end portion of the oil injection passage 7 is opened in the oil groove 51.