JPH0613871B2 - Scroll compressor - Google Patents

Description

TECHNICAL FIELD The present invention mainly relates to an oil return mechanism in a scroll compressor.

(Prior Art) Generally, in a scroll compressor, a fixed scroll and a movable scroll are arranged in a vertically opposed manner in an upper inner part of a hermetic casing, and a discharge pipe is connected to an upper side surface of the casing, The fluid compressed between both scrolls,
The fixed scroll is made to discharge to the outside through the discharge pipe.

By the way, in the scroll compressor as described above, a large amount of lubricating oil needs to be supplied to this sliding portion in order to ensure good sliding of both scrolls, and therefore a large amount of oil is mixed into the fluid. As a result, the amount of oil discharged from the discharge pipe to the outside also becomes large, and the amount of oil in the oil sump provided at the bottom of the casing decreases, causing a so-called oil rising problem. The oil spill occurred remarkably when the inverter control operation was performed and when the high speed control operation was performed.

Therefore, in order to prevent the above oil spillage, Japanese Patent Application No. 63-69156 (filed on Mar. 22, 1988) was previously proposed.

That is, the previously proposed one is as shown in FIG.
A fixed scroll (2) and a movable scroll (3) are arranged in a vertically opposed manner via a frame (4) on the inner upper part of the closed casing (1), and on the upper side of the fixed scroll (2), An oil separator (7) whose upper surface is closed so as to cover the discharge port (21) and discharge fluid can be discharged from the side portion.
And install the casing (1) with the oil separator (7).
The discharge chamber (5) formed on the inner upper side of the casing is defined as a fluid discharge chamber (51) and a discharge chamber (52), and an oil separator (7) on the side surface of the casing (1). A discharge pipe (8) is connected to a portion facing one side of the discharge chamber (52) to open the discharge chamber (52), and the discharge chamber (5) is opened.
On the bottom side of 2), an oil return port (9) extending to a lower low pressure region
And an oil return pipe (10) such as a capillary tube is provided in the oil return port (9), while the oil accumulated in the discharge chamber (51) is provided on the upper surface side of the fixed scroll (2). A communication groove (A) for guiding the oil to the oil return port (9) in the discharge chamber (52) is formed so as to directly communicate from the discharge chamber (51) to the oil return port (9). It is a thing.

Thus, from the discharge port (21) to the discharge chamber (51)
The oil discharged together with the fluid therein is separated by the oil separator (7) to discharge only the fluid from the discharge chamber (52) to the discharge pipe (8), and the oil separator (7). The oil separated in () is guided from the discharge chamber (51) to the oil return port (9) through the communication groove (A), and is quickly returned to the bottom oil sump of the casing (1). I have to.

(Problems to be Solved by the Invention) As described above, when the discharge pipe (8) is opened on the side surface of the casing (1) facing one side of the oil separator (7), the discharge pipe (8) is discharged. A linear fluid flow path connecting the shortest distance between the opening side of the pipe (8) and the discharge port (21) is formed, and only a part of the oil separator (7) positioned in this flow path range is formed. Since most of the fluid passes through, in other words, only a part of the oil separator (7) contributes to the oil separation, and most of the other part does not contribute to the oil separation.
There was a problem that the oil separation efficiency of the oil separator (7) was poor.

Further, in the above compressor, the inside of the discharge chamber (51) and the oil return port (9) are provided on the upper surface side of the fixed scroll (2).
Since the communication groove (A) that directly connects the and is formed, a part of the fluid in the discharge chamber (51) vigorously flows out to the discharge chamber (52) through the communication groove (A). At the time of this outflow, the oil located in the communication groove (A) and the oil return port (9) is blown upwards daily, and the oil return efficiency from the oil return port (9) to the oil sump side is poor, and There is also a problem that the oil blown up is sucked into the opening side of the discharge pipe (8) and causes oil to rise.

The present invention has been made in view of the above various problems,
It is an object of the present invention to provide a scroll compressor that can improve the oil separation efficiency and the oil return efficiency to the oil sump to solve the oil rising problem.

(Means for Solving the Problems) In order to achieve the above object, the present invention has a fixed scroll (2) and a movable scroll (3), which are provided in an upper portion of a hermetic casing (1). ), The discharge fluid is discharged from the discharge port (21) provided in the central portion of the fixed scroll (2) to the discharge chamber (5) provided above the discharge port (21). The discharge chamber (5) is provided with an oil separator (7) covering the discharge port (21) and closing the upper surface so that discharge fluid can be discharged from the side, on the upper part.
A discharge chamber (51) in which the discharge port (21) is opened.
And a discharge chamber (52) defined by the discharge chamber (51) and the oil separation (7) in the discharge chamber (52).
The opening (81) of the discharge pipe (8) is opened upward in the upper part of the above, and the oil return port (9) extending to the low pressure side is opened at the bottom of the discharge chamber (52), while the fixed scroll is opened. On the upper surface side of (2), one end is opened into the discharge chamber (51) and the other end is opened into the discharge chamber (52) so that oil accumulated in the discharge chamber (51) is discharged into the discharge chamber (51). A communication passage (12) for discharging to the bottom of (52) is formed, and an opening of the communication passage (12) to the discharge chamber (52) is formed at a position apart from the oil return port (9). I did.

(Operation) First, since the discharge pipe oil is opened above the oil separator (7) capable of discharging the discharge fluid from the side surface by closing the upper surface, the fluid discharged into the discharge chamber (51) is It is passed through the entire side of the oil separator (7) to the discharge chamber (52), so that the oil separator (7) can be effectively used,
The oil separation efficiency is increased by that much, and furthermore, since the opening (81) of the jet pipe (8) is opened upward above the oil separator (7), the oil separator (7) is opened.
The upward flow reaching the upper side of the oil separator (7) through the entire side part of the oil is changed to the downward flow, and the opening (8
1), so that even if oil remains in the discharge fluid discharged from the oil separator (7) into the discharge chamber (52), this oil causes the fluid flow from upward. The opening (8
It is possible to further separate by the time of 1), and the oil separation efficiency is further enhanced.

Further, since the opening of the communication passage (12) to the discharge chamber (52) is formed at a position apart from the oil return port (9), the discharge fluid passing through the communication passage (12). Part of the oil can be prevented from blowing up the oil near the oil return port (9) and the separated oil is prevented from flowing out of the discharge pipe (8) due to the blowing up of the discharge fluid. By this blow-up prevention, the oil return efficiency from the oil return port (9) to the bottom oil sump side of the casing (1) is enhanced.

(Embodiment) The scroll compressor shown in FIG. 1 includes a fixed scroll (2) having a discharge port (21) at the center and an orbiting scroll (3) on the inner upper side of a hermetic casing (1). ) And are supported by the frame (4) so as to face each other, and
A variable speed motor (M) is provided on the lower side of the casing (1).
And a drive shaft (S) of the motor (M) are interlockingly connected to the movable scroll roll (3) via a transmission mechanism (D), while a fixed scroll (2) is installed inside the casing (1). ), A discharge chamber (5) is formed on the upper side, and a suction chamber (6) is formed on the lower side of the movable scroll (3), so that the drive shaft (S) is rotated by the motor (M). , The movable scroll (3) is revolved around the fixed scroll (2) to compress the fluid sucked from the suction chamber (6) between the scrolls (2) and (3), The discharge port (21) is made to discharge into the discharge chamber (5).

Thus, in the scroll compressor described above, a cylindrical oil separator (7) having a closed upper surface is provided on the upper side of the fixed scroll (2) so as to surround the discharge port (21) thereof. Then, the inside of the discharge chamber (5) is located in the oil separation body (7) at the discharge chamber (51) where the discharge port (21) is open, and outside the discharge chamber (51), The discharge pipe (8) is partitioned into a discharge chamber (52) having an opening, and the discharge pipe (8) is connected to the upper side wall of the casing (1) above the fixed scroll (2). , The tip opening (81) of the discharge pipe (8),
It is located almost directly above the oil separator (7) inside the discharge chamber (52) and is opened upward.

The oil separator (7) is a cylindrical filter (71).
And a cylindrical cover body (72) having a closed upper surface fitted around the outer periphery of the filter (71) and having a plurality of opening windows (72a) on the side, and the discharge port (21) The fluid discharged from the fluid is filtered by the filter (71) to remove the oil component from the fluid, and only the fluid is opened in the opening window (72a).
To the discharge chamber (52).

Further, the discharge pipe (8) is divided into an inner pipe (8A) located on the inner side of the casing (1) and an outer pipe (8B) located on the outer side. Outer tube (8
A) and (8B) are respectively connected to a joint (8C) attached to the upper side wall of the casing (1), and a cover of the oil separator (7) is provided near the joint (8C) of the inner pipe (8A). Stand up along the side wall of the body (72),
The rising tip portion is bent along the upper surface of the cover body (72), and further bent upward at a position substantially above the center of the upper surface of the cover body (72), whereby the cover body (72) is bent. The upper end opening (81) of the inner tube (8A) is opened directly above.

As described above, the opening (81) of the inner pipe (8A) is opened upward at the position above the center of the oil separator (7) so that the discharge chamber (51) is discharged from the discharge chamber (5).
The flow path of the fluid leading to 2) is not specified at a fixed location, and the fluid discharged into the discharge chamber (51) is provided with each opening window (72a) provided on the outer periphery of the cover body (72). Through almost uniformly to reach the opening (81),
Therefore, the efficiency of oil separation by the filter (71) is improved.

Furthermore, since the opening (81) of the discharge pipe (8) is opened upward at a position above the oil separator (7),
The upwardly flowing discharge fluid that has passed through the oil separator (7) can be changed downward so as to reach the opening (81). The oil remaining in the can be further separated.

In addition, as is clear from FIG. 2, the fixed scroll (2) is formed on the outer peripheral surface of the upper surface of the fixed scroll (2) at the bottom side of the discharge chamber (52) defined by the oil separator (7). Oil return port (9) that penetrates 2) and the frame (4) to reach the suction chamber (6) of the casing (1).
A support body (11) is provided at the oil return port (9) with an oil return pipe (10) extending vertically from near the upper surface of the oil return port (9) to the suction chamber (6) side. The fixed scroll (2) is mounted on the upper surface of the fixed scroll (2) and has a groove extending in the radial direction, one end of which opens into the discharge chamber (51) and the other end of which opens into the discharge chamber (52). A communication passage (12) for discharging the oil accumulated in the discharge chamber (51) to the bottom of the discharge chamber (52) is formed, and an opening of the communication passage (12) to the discharge chamber (52) is formed. To be at a position separated from the oil return port (9) by a predetermined distance, that is,
The openings are formed at positions separated by a predetermined angle in the circumferential direction.

Next, the communication passage (12) to the oil return port (9)
The actual measurement data when variously changing the separation angle of the discharge chamber (52) side opening will be described. The oil rising rate, which will be described later, is a numerical value calculated by the formula: (amount of oil contained in discharge gas) / (discharged gas + amount of oil contained in discharge gas) × 100%.

First, the communication passage (12) is formed as a radially extending groove having a width of 8 mm and a depth of 5 mm, and the communication passage (12) is provided to the oil return port (9) with respect to the discharge port of the fixed scroll (2). The oil rising rate in the case of being separated by 30 degrees in the circumferential direction around (21) is 0.70%, and the same communication passage (12) as described above is connected to the oil return port (9). On the other hand, the oil rising rate when it is separated by 180 degrees in the circumferential direction is 0.23.
%.

On the other hand, as a comparative example of the present invention, the same communication passage (1
It was also actually measured that 2) was provided in direct communication with the oil return port (9), but the oil rising rate in this case was 2.08.
%, As compared with this oil rise rate, the oil rise rate when the oil return port (9) of the communication passage (12) is separated from the oil return port (9) by a predetermined angle in the circumferential direction is remarkably reduced. Therefore, by separating the communication passage (12) from the oil return port (9), the amount of oil sucked into the discharge pipe (8) can be reduced and, at the same time, the oil return port (9). It is possible to increase the amount of oil returned from 9).

(Effect of the invention) As described above, in the scroll compressor of the present invention, the fixed scroll (2) is covered with the discharge port (21) and the upper surface is closed to discharge from the side. An oil separation body (7) capable of discharging a fluid is provided, and the discharge chamber (5) includes a discharge chamber (51) in which the discharge port (21) is opened, and the discharge chamber (51). It is divided into a defined discharge chamber (52) and an opening (81) of the discharge pipe (8) is opened upward at a position above the oil separator (7) in the discharge chamber (52), The discharge chamber (5
An oil return port (9) extending to the low pressure side is opened at the bottom of 2), while one end is opened in the discharge chamber (51) and the other end is discharged at the upper face side of the fixed scroll (2). Room (5
2) forms a communication passage (12) that opens into the discharge chamber (51) and discharges the oil accumulated in the discharge chamber (51) to the bottom of the discharge chamber (52), and discharges the communication passage (12). Since the opening to the chamber (52) is formed at a position separated from the oil return port (9), first, the upper surface is closed, and the discharge fluid can be discharged from the side surface above the oil separator (7). By opening the discharge pipe (8) at the position, the fluid discharged into the discharge chamber (51) is passed through the entire side portion of the oil separator (7) to the discharge chamber (52), Therefore, the oil separator (7) can be effectively used, the oil separation efficiency can be enhanced accordingly, and the opening (81) of the discharge pipe (8) can be further improved.
Is opened upward at a position above the oil separator (7), the upward flow reaching the upper side of the oil separator (7) through the entire side portion of the oil separator (7) is directed downward. It can be turned into a flow to reach the opening (81), and thus even if oil remains in the discharge fluid discharged from the oil separator (7) into the discharge chamber (52), The oil can be further separated by the resistance by changing the flow of the fluid from upward to downward until it reaches the opening (81), so that the oil separation efficiency is further enhanced.

Further, since the opening of the communication passage (12) to the discharge chamber (52) is formed at a position apart from the oil return port (9), the discharge fluid passing through the communication passage (12). Part of the oil can be prevented from blowing up the oil near the oil return port (9) and the separated oil is prevented from flowing out of the discharge pipe (8) due to the blowing up of the discharge fluid. By this blow-up prevention, the oil return efficiency from the oil return port (9) to the bottom oil sump side of the casing (1) is enhanced.

Therefore, it is possible to prevent the separated oil from flowing out of the discharge pipe (8) while improving the separation efficiency of the oil mixed in the compressed discharge fluid, so that the oil return efficiency is also improved and the compressor is also improved. It is possible to improve the reduction of oil spillage.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a main part of a scroll compressor according to the present invention, FIG. 2 is a plan view of a fixed scroll, and FIG.
The figure is a cross-sectional view showing a conventional example. (1) ... closed casing (2) ... fixed scroll (21) ... discharge port (3) ... movable scroll (5) ... discharge chamber (51) ... discharge chamber (52) ... discharge chamber (7) …… Oil separator (8) …… Discharge pipe (81) …… Opening (9) …… Oil return port (12) …… Communication passage

Claims (1)

[Claims] 1. A discharge port (21) in which a fixed scroll (2) and a movable scroll (3) are installed in the upper part of a closed casing (1), and which is provided in the center of the fixed scroll (2).
In the scroll compressor in which the discharge fluid is discharged to the discharge chamber (5) provided above the discharge port (21), the discharge port (21) is covered above the fixed scroll (2). Further, the upper surface is closed, and the oil separation body (7) capable of discharging the discharge fluid from the side is disposed, and the discharge chamber (5) is connected to the discharge port (21).
Is divided into a discharge chamber (51) having an opening and a discharge chamber (52) defined by the discharge chamber (51).
An opening (81) of the discharge pipe (8) is opened upward at a position above the oil separator (7) in 2), and an oil return port (low pressure side) is provided at the bottom of the discharge chamber (52). 9), while opening one end into the discharge chamber (51) and the other end into the discharge chamber (52) on the upper surface side of the fixed scroll (2), 51)
A communication passage (12) for discharging the oil accumulated therein to the bottom of the discharge chamber (52) is formed, and an opening of the communication passage (12) to the discharge chamber (52) is formed at the oil return port ( 9) A scroll compressor characterized in that it is formed at a position apart from 9).