JPH04203379A - Closed scroll type compressor - Google Patents

Abstract

PURPOSE:To reduce an amount of sucked-up oil and to cool a lower part of a motor by a method wherein a passage for communicating an upper part and a lower part of a scroll compressor is provided under an arrangement of combination of a recessed passage, a clearance and a supporting column passage. CONSTITUTION:Almost of all oils separated from refrigerant gas in an upper spacing 17 are accumulated at an outer circumferential part of a fixed scroll 5, dropped along an inner wall of a closed container through a recessed passage 5b at the outer circumference and a clearance 7a at an outer circumference of an upper end of a frame 7, thereafter the oil is flowed down passages 19 and 22 disposed at a part of the circumference of an electrical motor 3 and returns to an oil reservoir 4. On the other hand, the refrigerant gas is flowed form the upper spacing of the compressor 2 toward a lower part of the compressor through a supporting column passage 7c of the frame 7 disposed in opposition to a passage 19 disposed at a part of the circumference of the electrical motor 3 as well as a recessed passage 5b of the fixed scroll 5 and the passage 7c is oppositely disposed against the passage 19 passing downwardly and disposed at a part of the circumference part of the electrical motor, resulting in that the refrigerant may pass effectively through this passage 19 so as to cool the lower part of the electrical motor and then the gas is flowed out of the discharging pipe while being separated from the oil.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a hermetic scroll compressor, and in particular, it relates to a hermetic scroll compressor, and particularly to a so-called oil rise where lubricating oil flows out of the compressor along with discharged gas. Regarding improvements to prevent this.

[Conventional technology]

Hermetic scroll compressors are often used to compress refrigerant gas in air conditioners, and are generally housed in an airtight container with a compressor section at the top and an electric motor to drive it at the bottom. is provided with an oil reservoir containing lubricating oil (hereinafter simply referred to as oil). The compressor section consists of a fixed scroll and an orbiting scroll that are engaged with each other, each having a circular involute or similar spiral wrap, and the fixed scroll is cranked so that it revolves around the fixed scroll without rotating on its own axis. Driven by a shaft. This crankshaft is driven by an electric motor. The fixed scroll, orbiting scroll, and crankshaft are supported by a frame fixed to the closed container.

The oil is sucked up from the oil reservoir into the oil passage inside the crankshaft,
After lubricating each bearing and scroll sliding surface, the refrigerant is discharged into the space inside the sealed container above the compressor part together with the refrigerant gas compressed in the compressor part, and the refrigerant is formed between the frame and the inner wall of the sealed container. The refrigerant gas enters the space below the frame through the passage and returns to the oil reservoir through the refrigerant passage formed between the electric motor and the sealed container. It is discharged outside the closed container from a discharge pipe connected to the container.

For conventional hermetic scroll compressors, Japanese Patent Application Laid-Open No. 63-21
As shown in Japanese Patent No. 2796, a plurality of grooves with varying resistances are provided on the side surface of the frame to communicate from the space in the airtight container above the compressor section to the lower end of the frame, and through these grooves, the passage above the compressor section is communicated with the lower end of the frame. It was designed to allow refrigerant gas to flow downwards.

[Problem to be solved by the invention]

In the above conventional technology, the oil is separated from the refrigerant gas in the space inside the airtight container above the compressor part, but when the oil and gas flow through the passage provided on the side of the frame, they mix and flow. There was a problem in that only a small amount of oil adhered to the inner wall of the lower closed container, and the oil mixed with gas and exited from the discharge connection port, resulting in a large amount of oil coming up. In addition, since the passage has a groove shape, the contact area with the inner wall of the sealed container is small and there is a problem that it is not necessarily sufficient to make the oil in the refrigerant gas that has flowed through the passage adhere to the inner wall of the sealed container6. An object of the present invention is to provide a hermetic scroll compressor that reduces the amount of oil coming out and cools the lower part of the motor.

[Means to solve the problem]

In order to achieve the above object, the present invention includes a fixed scroll disposed in a closed container, an orbiting scroll that meshes with the fixed scroll, and a rotary scroll that is integrally coupled to the fixed scroll and supports the orbiting scroll so as to be able to freely rotate. A compressor section consisting of a frame in close contact with the compressor section is provided in the upper part, an electric motor for driving an orbiting scroll is provided below the compressor section, and a lubricating oil reservoir is provided at the bottom of the closed container below the electric motor,
A discharge pipe communicating with the outside of the sealed container is connected to the space between the compressor section and the electric motor, and compressed refrigerant gas containing lubricating oil is discharged from the central discharge port of the fixed scroll into the space above the compressor section. In a hermetic scroll compressor, the support provided on the outer periphery of the frame is tightly fixed to the closed container, and the diameter of the outer periphery of the upper end of the frame is smaller than the diameter of the frame support, so that the inner wall of the closed container is A gap passage is provided around the entire circumference, and the outer diameter of the fixed scroll is set to such a diameter that almost no refrigerant gas or oil flows between the inner walls of the closed container. The passage is = 4 - The passage is provided so as to communicate with a portion of the gap passage provided in the frame other than between the frame ribs surrounding the discharge connection port provided on the closed container, and furthermore, one of the frame support portions is , the space above the motor provided in a part of the circumference of the motor faces a passage communicating with a lubricating oil reservoir below the motor, and is also provided with a groove.

[Effect]

The oil sucked up from the lubricating oil reservoir and lubricating each bearing and scroll sliding part is mixed with refrigerant gas and discharged from the central discharge port of the fixed scroll into the space above the compressor section. Most of the oil separated from the refrigerant gas in the upper space collects on the outer periphery of the fixed scroll, and passes through the notch passage provided on the outer periphery of the fixed scroll and the gap on the outer periphery of the upper end of the frame.
After falling along the inner wall of the sealed container, it flows down a passage provided in a part of the circumference of the electric motor and returns to the oil sump.

On the other hand, the refrigerant gas flows from the space above the compressor section to the lower part of the compressor through a notch passage in the fixed scroll and a support passage in a frame that is provided opposite to a passage provided in a local part of the motor. flows.

In addition, since the passage faces a passage extending downward provided in a part of the circumference of the electric motor, the refrigerant gas effectively enters the space below the electric motor through this passage and cools the lower part of the electric motor. After that, it passes through a passage provided around the motor and reenters the space between the motor and the compressor section. Refrigerant gas separates from oil from the space between the electric motor and the compressor section and flows out of the closed container through the discharge pipe.

〔Example〕

An embodiment of the present invention is shown in FIGS. 1 and 2 below.

This will be explained with reference to FIG. FIG. 1 shows a sectional view of the entire structure of a hermetic scroll compressor embodying the present invention. Figure 2 is a bottom view of the fixed scroll in the same embodiment, and Figure 3 (a
) and (b) show a bottom view and a partial side view of the frame in the same embodiment.

In FIG. 1, a compressor section 2 is disposed above and an electric motor 3 is disposed below inside a closed container 1, and an oil reservoir 4 for lubrication is formed at the bottom of the closed container 1. The compressor section 2 includes a fixed scroll 5 having a spiral wrap 5a on a base plate, and a spiral wrap 6a also on the base plate.
The frame 7 is integrated with the fixed scroll 5 and supports the orbiting scroll 6, and the ramps of the fixed scroll 5 and the orbiting scroll 6 are engaged with each other. Furthermore, an Oldham mechanism 8 is provided between the orbiting scroll 6 and the frame 7 to prevent the orbiting scroll 6 from rotating. The electric motor 3 is press-fitted into the closed container 1 and is configured to rotate the orbiting scroll 6 via the crankshaft 9. The crankshaft 9 is supported by a main bearing 10 and a lower bearing 11 provided on the frame 7,
The crank pin is fitted with an orbiting bearing 12 provided on the back surface of the orbiting scroll 6.

Inside the crankshaft 9 is a main bearing 10. An oil supply passage 13 that guides lubricating oil to the lower bearing 11 and the swing bearing 12 is provided, and an oil supply device 14 that sucks up the lubricating oil from the oil reservoir 4 and sends it to the oil supply passage 13 is provided at the shaft end of the electric motor 3. .

In the compressor section 2, when the orbiting scroll 6 makes an orbiting motion via the crankshaft 9 driven by the electric motor 3, the space (compression chamber) formed by the orbiting scroll 6 and the fixed scroll 5 moves toward the center of the scroll. As it moves, it reduces its volume and compresses the sucked refrigerant gas. The compressed refrigerant gas is discharged from a discharge port 16 provided at the center of the white plate of the fixed scroll to an upper space 17 within the closed container.

Furthermore, an intermediate pressure chamber 15 is formed on the back surface of the orbiting scroll to which gas for the compression stroke is guided.

The pressure in the intermediate pressure chamber 15 is between the suction pressure and the discharge pressure of the refrigerant gas, and oil supply to the sliding portion of the scroll is performed using the differential pressure between the discharge pressure and the intermediate chamber pressure. The lubricating oil passes through the oil supply passage 13 from the oil supply device 14 and is delivered to the main bearing 10.
After lubricating the lower bearing 11 and the swing bearing 12, the mixture flows into the compression chamber via the intermediate pressure chamber 15, and is mixed with refrigerant gas. It is discharged into the space 17.

As shown in FIG. 2, a plurality of cutout passages 5b are provided on the outer circumference of the fixed scroll 5. As shown in FIG.

Q- Also, the outer diameter portion 5c is provided with a small gap with the airtight container 1, but the gap is designed to prevent refrigerant gas and oil from flowing through. As shown in FIG. 3, the outer circumference of the upper end of the frame 7 is made to have a dimension smaller than the diameter of the support column 7b of the frame 7 over the entire circumference so as to form a passage with the closed container 1, and a gap passage 7a is formed therein. There is. In addition, the support 7 of the frame 7
A groove-shaped passage 7c is provided in b.

A notch passage 5b provided in the fixed scroll 5 communicates with a passage 7c provided in the scroll 7, and another notch passage 5b is connected to the airtight container 1 among the gap passages 7a provided in the frame 7. It is provided at a position communicating with a portion other than between the ribs 7d of the frame 7 surrounding the discharge connection port 21 provided above.

In addition, the space below the compressor section 2, that is, the frame 7
By partially cutting the core of the motor 3, a refrigerant passage 19° 22 for communicating the space between the lower part of the motor and the upper part of the motor with the space below the motor 3 is formed inside the motor 3 and the closed container 1. formed between the wall.

-10= A groove-shaped passage 7C provided in the support column 7b of the frame 7, which is a refrigerant passage, is located so as to face the passage 19 formed by the core cut portion of the electric motor 3 in the axial direction.

In FIG. 1, reference numeral 20 denotes a suction pipe that passes through the closed container 1 and guides refrigerant gas from the outside of the closed container 1 to the suction side of the compressor section 2. Reference numeral 21 denotes a discharge pipe connected to a space between the compressor section 2 and the electric motor 3 in the closed container 1, and compressed refrigerant gas flows out of the closed container 1 from this discharge pipe. This discharge pipe 21 is connected to the airtight container 1 on the side farther from the passage 7c.
It is connected to the.

Next, the operation will be explained. When the orbiting scroll is rotated by the electric motor 3 via the crankshaft 9, the suction pipe 2
The refrigerant gas sucked in from 0 is compressed by the action of the fixed scroll 5 and the orbiting scroll 6, and then
The lubricant is mixed with lubricating oil and discharged into the upper space 17 above the closed container from a discharge port 16 provided at the center of the container. This discharged refrigerant gas collides with the lid cap 1a of the closed container 1, and oil and refrigerant gas are separated. The separated oil temporarily accumulates on the upper outer periphery of the fixed scroll 5, and then passes through the notch passage 5b of the fixed scroll 5 and the gap passage 7 provided on the outer periphery of the frame 7 to reach the inner wall surface of the closed container 1. It flows into the space below the compressor section, that is, the space between the frame 7 and the electric motor 3. At this time, the contact area between the closed container 1 and the oil is large and narrow, so that the oil flowing down the gap passage 7a can flow smoothly downward while adhering to the inner wall surface of the closed container 1. The oil that has flowed into the space then flows down the passage formed by the sealed container 1 and the core cut portion of the electric motor 3 due to its own weight, and flows down to the oil sump 4 at the bottom of the sealed container.

On the other hand, the refrigerant gas flows from the upper space 17 into the space between the frame 7 and the electric motor 3 through the groove-shaped passage 7c.

At this time, oil and refrigerant gas are separated in the upper space 17, and refrigerant gas flows in the passage.

Further, the passage inlets and outlets of the gap passages 7a and the groove-shaped passages 7c provided in the frame 7 are open to the same space, and the pressure difference between the inlets and the outlets is equal. Comparing the specific gravity of oil and refrigerant gas at discharge pressure, the specific gravity of oil is higher. Therefore, the oil flows down the gap passage 7a, and the groove-shaped passage 7
When the refrigerant gas flows through C, the speed of the refrigerant gas is greater than the speed of the oil flowing through the gap passage 7a. Furthermore, since the groove-shaped passage 7C faces the passage 19 to the lower part of the electric motor formed by the core cut portion of the electric motor 3, the groove-shaped passage 7C
The refrigerant gas that has passed through c flows into the lower part of the electric motor 3 through the passage 19, and can effectively cool the lower part of the electric motor 3. The refrigerant gas that has cooled the lower part of the motor passes through the passage 22 on the outer circumference of the motor and reaches the space above the motor. The refrigerant gas that has cooled the motor in this way flows out of the closed container 1 from the discharge pipe 21.

〔Effect of the invention〕

According to the present invention, the hermetic scroll compressor effectively separates the oil contained in the compressed refrigerant gas and returns it to the oil reservoir, effectively preventing so-called oil drainage, and 'It is possible to prevent the temperature rise of the windings at the bottom of the motor by sufficiently flowing refrigerant gas to the bottom of the motor for cooling.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of a hermetic scroll compressor according to an embodiment of the present invention, FIG. 2 is a bottom view of a fixed scroll in the same embodiment, and FIGS. 3(a) and 3(b) are the same. It is a bottom view and a partial side view of the frame in an example. 1... Airtight container, 2... Compressor section, 3... Electric motor,
4... Oil reservoir, 5... Fixed scroll, 6... Orbiting scroll, 7... Frame, 9... Crankshaft,
10...Main bearing, 11...Lower bearing, 12...Swivel bearing, 13...Oil supply passage. 17th D Iku lro 17 20”” 5a 5 drinks to Otsu 5d 2nd country to Otsu layer

Claims (1)

[Claims] 1. A pair of scrolls are provided on a base plate, and the scrolls are moved relative to each other so that the volume of the space formed by the base plate and the teeth of the scroll decreases as the space moves toward the center of the scroll. A compressor section is provided in the upper part of the sealed container, an electric motor for driving the scroll compressor part is provided in the lower part, an oil sump part is provided in the bottom of the sealed container, and the scroll compressor part and the electric motor are connected to each other. In a hermetic scroll compressor in which a discharge connection port is provided on the hermetic container between the two, a strut provided on the outer periphery of the frame is closely fixed to the hermetic container, and the outer periphery of the upper end of the frame is connected to the inner wall of the hermetic container. A gap is provided along the entire circumference between the stators, and a support passage larger than the gap is provided in at least one support on the outer periphery of the frame opposite to the passage formed by the stator of the electric motor and the closed container; Further, a plurality of notched passages formed with the inner wall of the sealed container are provided in the outer peripheral portion of the fixed scroll, and the plurality of notched passages formed by a combination of the notched passage, the gap, and the support passage are provided. A hermetic scroll compressor characterized in that a passage is provided that communicates the upper and lower parts of the scroll compressor section.