KR20060013218A - Oil supply apparatus for compressor - Google Patents

Abstract

The oil supply device of the compressor of the present invention is provided on one side of the compressor case and has an oil tank having a predetermined space for storing oil therein, and one end is connected to communicate with the inside of the compressor case and the other end is connected to the oil tank. An oil supply pipe connected to supply excess oil inside the compressor case to the oil tank, and connected to one end of the oil tank and connected to the other end of the compressor case to return oil stored in the oil tank to the inside of the compressor case. Composed of an oil return tube, the excess oil in the compressor case is stored in the oil tank and continuously supplied to the compression chamber of the compressor, so that the compressor always ensures a stable flow rate even in a long pipe length and large drop system. The reliability of is secured.

Description

OIL SUPPLY APPARATUS FOR COMPRESSOR}

1 is a schematic view showing a refrigeration system in which a compressor to which an embodiment of the present invention is applied is installed.

FIG. 2 is a longitudinal sectional view of the compressor in FIG. 1. FIG.

3 is a cross-sectional view taken along the line AA ′ of FIG. 2;

Figure 4 is a partial cross-sectional view showing a modification of the oil supply structure in one embodiment of the present invention.

5 is a Moriel diagram of the prior art and the present invention.

6 is a schematic view showing another embodiment of the present invention.

7 is a schematic view showing another embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

3: discharge tube 4: condenser

11: compressor case 17: lower bearing

17a: coupling hole 22: oil supply pipe

22a: first supply pipe 22b: second supply pipe

23: injection pipe 24: oil return pipe

26: oil supply hole 29: stent tube

30,30 ': oil

The present invention relates to an oil supply device for a compressor, and more particularly, to an oil supply device for a compressor such that a stable flow rate is always ensured inside the compressor to ensure reliability of the compressor.

Most home air conditioners use rotary compressors, and commercial air conditioners also have relatively low cost rotary compressors. There is also a tendency to use rotary compressors globally in multi air conditioning systems.

In general, excessively high oil level in the compressor may interfere with the rotor of the motor, or may be blown by the gas discharged from the muffler, causing a large amount of oil to flow out to the system through the discharge pipe, leading to deterioration of the heat exchanger or instability of the system. not. Therefore, the design sealing flow rate of the compressor should be optimized.

Especially in air conditioning systems with long pipe lengths and large drop-offs, such as commercial air conditioners and multi-type air conditioning systems, the amount of oil circulating or staying in the system changes greatly during abnormal operation of the system, resulting in excessive or insufficient compressor flow. do.

However, the conventional compressor has a problem that there is a limit in improving the reliability of the compressor by a stable oil supply because it is not possible to bring enough oil loading amount due to the oil storage limitation does not cause the above problems.

 SUMMARY OF THE INVENTION An object of the present invention devised in view of the above problems is to provide an oil supply device for a compressor suitable for supplying sufficient oil to the compressor at all times so that the compressor can be stably maintained.

In order to achieve the object of the present invention as described above,

An oil tank provided at one side of the compressor case and having a predetermined space for storing oil therein;

An oil supply pipe connected to one end of the compressor case so as to communicate with the inside of the compressor case and the other end connected to the oil tank to supply excess oil in the compressor case to the oil tank;

The oil return pipe is connected to one end of the oil tank and the other end is connected to the compressor case to return oil stored in the oil tank to the inside of the compressor case.

An oil supply apparatus for a compressor is provided, which is configured.

In addition, the oil tank is provided on one side of the compressor case and has a predetermined space for storing oil therein;

An oil supply pipe connected to one end of the compressor case so as to communicate with the inside of the compressor case and the other end connected to the oil tank to supply excess oil in the compressor case to the oil tank;

One end is connected to the oil tank and the other end is connected to the inlet of the accumulator to return the oil in the oil tank to the accumulator,

An oil supply apparatus for a compressor is provided, which is configured.

In addition, the oil tank is provided on one side of the compressor case and has a predetermined space for storing oil therein;

A first supply pipe connected to one end of an upper end of the oil tank and connected to a discharge pipe installed at an upper end of the compressor case to supply refrigerant and oil discharged to the discharge pipe to an oil tank;

A second supply pipe having one end connected to the other end of the upper end of the oil tank connected to a condenser to supply only refrigerant gas from the oil tank to the condenser;

One end is connected to the lower end of the oil tank and the other end is connected to the side of the compressor case is an oil return pipe for returning the oil stored in the oil tank to the inside of the compressor case,

An oil supply apparatus for a compressor is provided, which is configured.

Hereinafter, the oil supply device of the compressor according to the present invention configured as described above will be described in more detail with reference to an embodiment of the accompanying drawings.

1 is a schematic diagram of a refrigeration system in which a compressor to which an embodiment of the present invention is applied is installed, and as shown therein, a rotary compressor 1, a condenser 4, an expansion valve 5, and an evaporator 6 are sequentially connected. The refrigerant gas compressed by the rotary compressor (1) is discharged from the compressor (1) at high pressure and sent to the condenser (4), and the pressure is dropped from the expansion valve (5) via the condenser (4) to evaporator (6). The vaporized refrigerant gas is sucked back into the rotary compressor (1) to repeat the freezing cycle.

In addition, the rotary compressor 1 is provided with an oil tank 8 on one side so that it is possible to always supply an appropriate amount of oil to the compressor 1.

FIG. 2 is a longitudinal cross-sectional view of the compressor in FIG. 1, and FIG. 3 is a cross-sectional view taken along the line AA ′ of FIG. 2. As shown in the drawing, the rotary compressor 1 has a compressor case having a predetermined space therein ( 11, a pump assembly 9 and a motor assembly 10 are installed.

The pump assembly 9 consists of a cylinder 12, a roller 13, a crankshaft 14, a vane 15, an upper bearing 16 and a lower bearing 17, the pump assembly 9 of which It is driven by a motor assembly 10 consisting of a rotor 28 and a stator 27.

In addition, the compression chamber 25 is formed by the cylinder 12 and the upper and lower bearings 16 and 17, and a suction hole 18 is formed in communication with one side of the compression chamber 25. A suction pipe 2 connected to the lower end of the accumulator 7 is connected to the suction hole 18. The refrigerant gas flowing into the compression chamber 25 through the suction pipe 2 is rotated by the rotation of the crankshaft 14, the roller 13 is rotated and the discharge hole 19 formed in the upper bearing 16 after compression Through the muffler 20 is discharged through.

The inner bottom of the compressor case 11 includes an oil sump 21 in which oil 30 is stored, and the oil 30 stored in the oil sump 21 is sealed to the upper end of the cylinder 12 and shipped. do.

In addition, the outer side of the compressor case 11 is provided with an oil tank (8) for storing the oil (30) separately and to supply to the friction portion of the compression chamber (25).

The oil tank 8 is a sealed high pressure container capable of storing the oil 30 'therein, and an oil supply pipe through which the oil 30' stored in the compressor case 11 is supplied to the oil tank 8. 22 and the oil 30 'of the oil tank 8 are connected to the oil return pipe 24 which is returned to be supplied to the friction part inside the compressor case 11, and the oil inside the compressor case 11 is connected to the oil return pipe 24. A stand tube 29 is provided to prevent back flow of the oil 30 ′ supplied to the oil tank 8 through the supply pipe 22.

One end of the oil supply pipe 22 is connected to the side of the compressor case 11, and the height of the connection portion is located near or slightly above the center of the cylinder 12. The oil 30 whose oil level rose above this height flows in to the oil tank 8 side.

The oil return pipe 24 is positioned below the oil supply pipe 22 and is inserted into the coupling hole 17a formed at one side of the lower bearing 17 through the compressor case 1 to be inserted into a predetermined portion. It is connected to the outer end of the pipe 23, and the coupling hole 17a is communicated with the compression chamber 25 by the oil supply hole 26 formed in the lower bearing 17.

  The diameter of the oil supply hole 26 is usually 1-2 mm, and is opened and closed by the lower surface of the roller 13 when the roller 13 slides in the compression chamber 25. In addition, the oil supply hole 26 does not open to the inner diameter of the roller 13. That is, the oil supply hole 26 starts opening immediately after the outer circumference of the roller 13 passes through the suction hole 18 of the cylinder 12, before the pressure of the compression chamber 25 becomes higher than the discharge pressure. It is supposed to close. Therefore, the internal pressure of the oil supply hole 26 is lower than the pressure on the high pressure side or the internal pressure of the compressor case 11 that is higher than the pressure on the low pressure side.

The oil supply hole 26 has a large oil return amount in the compression chamber 25 when the opening angle range or the opening time is long, and the oil return amount is small when the opening time is short. Therefore, it is desirable to optimize the opening time to some extent, whereby the oil return amount of the compression chamber 25 is determined. In this way, the oil injected into the compression chamber 25 of the cylinder 12 does not leak to the suction hole 18 side.

4 is a variation of the oil supply structure in one embodiment of the present invention, as shown therein, the oil supply hole 26 of the cylinder 12 at a position approximately 180 degrees opposite to the vane 15. The injection pipe 23 is connected to the oil supply hole 26 formed in such a manner as to be directly opened in the compression chamber 25. The injection tube 23 is inserted into the guide tube 27 having a larger diameter than the injection tube 23 previously installed on the side surface of the compressor case 11, and welded to the guide tube 27. The oil supply pipe 22 may be connected to the side of the compressor to simplify the connection with the compressor case 11. A space 27a is formed between the guide tube 27 and the injection tube 23 so that the oil of the compressor case 11 flows into the oil supply pipe 22 through the space 27a.

The operational effects according to the embodiment of the present invention configured as described above are as follows.

When the operation of the compressor starts, since the oil return pipe 24 connected to the oil tank 8 communicates with the oil supply hole 26 through the injection pipe 23, the pressure of the oil tank 8 is equal to the discharge pressure or The pressure is slightly lower than the internal pressure of the compressor case 11. Therefore, the excess oil in the compressor case 11 is supplied to the oil tank 8 through the oil supply pipe 22 and the stand pipe 29, and stored. That is, the excess oil of the compressor is stored in the oil tank (8).

In such a state, the pressure of the oil supply hole 26 opened in the compression chamber 25 of the cylinder 12 is lower than the pressure of the oil tank 8 so that the oil of the oil tank 8 is the oil return pipe 24. And the injection pipe 23 are moved to the oil supply hole 26, and is injected into the compression chamber 25 only while the oil supply hole 26 is opened. The oil injected into the compression chamber 25 of the cylinder 12 is mixed in the compressed gas to lubricate the friction part, and is discharged into the compressor case 11 through the muffler 20 through the discharge hole 19. The oil sump 21 is returned.

The oil increased in the oil sump 21 is used in the compressor as it is when the amount of oil in the compressor is insufficient, but if excessive, a circulation cycle for returning to the oil tank 8 is performed.

That is, as described above, an appropriate amount of oil is always supplied from the oil tank 8 to the compressor friction portion, and the stand tube 29 installed inside the oil tank 8 is located above the inside of the oil tank 8. Since it is open, the oil 30 'of the oil tank 8 does not flow back to the compressor during the stop of the compressor. In addition, since the oil is injected into the compression chamber 25 after the roller 13 passes through the suction hole 18, the oil and the refrigerant mixed with it do not flow back into the suction hole 18.

Conventionally, excess oil of the compressor escapes to the low pressure side and is returned to the inside of the compressor case 11 through the suction hole 18. There is a difference when comparing the conventional method with the present invention. .

5 is a Moriel diagram of the prior art and the present invention.

Where the vertical axis is the pressure (P) of the refrigeration cycle and the horizontal axis is the enthalpy (i). G is the amount of refrigerant that normally circulates in the refrigeration cycle when oil does not return. While the compressor is running or stopped, the oil of the oil sump 21 contains about 10-70% of the refrigerant.

a) shows a conventional system in which oil containing refrigerant returns from the compressor by g to the low pressure side of the compressor or system. When the oil returns to the low pressure side, the amount of intake gas of the compressor decreases by g and becomes G-g. The freezing capacity Q at which the amount of refrigerant circulating in the evaporator is obtained is Q = (G-g) (i2-i3), and the freezing capacity is reduced by g (i2-i3) by the oil return amount g. On the other hand, the compressor input (W) can be expressed as W = G (i0-i2) and there is no increase in input according to g.

b) shows the system of the present invention where the oil does not return to the low pressure side, so Q = G (i2-i3), but W = G (i1-i2) + (G + g) (i0-i1) = G ( i0-i2) + g (i0-i1), and if the oil return amount (g) is large, the input increases by that amount. That is, in the present invention in which oil is returned to the compression chamber 25 of the cylinder 12, the input is increased by g (i0-i1).

Here, comparing the efficiency reductions of both methods, the conventional system is g (i2-i3), whereas the system of the present invention is g (i0-i1). Since the conventional enthalpy difference i2-i3 is considerably large with respect to the latter enthalpy difference i0-i1, the efficiency decrease is large, and the latter can be said to be small. For example, assuming that the amount of g is 10% of G (g / G = 0.1), the former has a 10% refrigeration capacity while the latter has an input increase of less than 2%. Furthermore, in the latter case, the oil is injected from the pressure of the compression chamber 25 close to the discharge pressure in order to minimize the deterioration of efficiency since the cylinder 12 also changes depending on the timing of oil injection into the compression chamber 25. In addition, in the latter case, oil is injected directly into the compression chamber 25 of the cylinder 12 to help lubricate the sliding parts in the compression chamber 25. As a result, the life of the compressor can be extended, and the gas sealing function can be increased to increase the compression efficiency.

6 is a schematic view showing another embodiment of the present invention. As shown in FIG. 6, since the basic structure is the same as that of the above-described embodiment, the same components will be denoted by the same reference numerals and detailed description thereof will be omitted.

It is also possible here to connect the oil return tube 24 to the inlet side of the accumulator 7 to inject the oil 30 'of the oil tank 8 into the low pressure side of the system to return to the compressor case 11. Do.

In such a configuration, since the compressor is always operated while ensuring a stable flow rate by the oil 30 'of the oil tank 8, the reliability is improved as compared with the conventional art.

Figure 7 is a schematic view showing another embodiment of the present invention, as shown in this, is installed between the compressor discharge pipe 3 and the condenser 4 in the upper end of the oil tank 8 is oil separation is performed, A first supply pipe 22a connected to the discharge pipe 3 and an upper end of the oil tank 8 and a second supply pipe 22b connecting the other end of the upper end of the oil tank 8 to the condenser 4, An oil return pipe 24 connecting the lower end of the oil tank 8 and the compression chamber 25 of the cylinder 12 is installed to separate the refrigerant and the oil discharged into the discharge tube 3 so that the refrigerant is a condenser 4. ) And the oil is to be returned to the compression chamber (25).

In the above embodiment, the rotary compressor has been described as an example, but it is obvious that the present invention can be applied to a similar compressor such as a scroll compressor without departing from the spirit and scope of the present invention.

As described in detail above, the oil supply device of the compressor of the present invention is a stable supply of oil stored in the oil tank in the compressor tank is always secured to ensure a stable flow rate even in a long pipe length and large drop system Reliability is secured.

In addition, since the oil supplied from the oil tank to the compressor is directly supplied to sliding parts such as rollers or vanes in the compression chamber, the life of the parts of the compressor is increased, and the compression efficiency is improved by increasing the gas sealing capacity of the rollers or vanes. .

In addition, by providing the oil supply pipe and the oil return pipe at the same position, the compressor casing and the pipe connection thereof are easy, and the complicated pipe connection is simplified.

Claims (7)

An oil tank provided at one side of the compressor case and having a predetermined space for storing oil therein; An oil supply pipe connected to one end of the compressor case so as to communicate with the inside of the compressor case and the other end connected to the oil tank to supply excess oil in the compressor case to the oil tank; The oil return pipe is connected to one end of the oil tank and the other end is connected to the compressor case to return oil stored in the oil tank to the inside of the compressor case. Oil supply device of the compressor, characterized in that configured.        The method of claim 1,        The inside of the oil tank is a compressor, characterized in that further provided with a stand tube is arranged in the vertical direction so that one end is connected to the oil supply pipe and the upper end is opened to prevent the reverse flow of the oil supplied to the oil tank through the oil supply pipe Oil supply system. The method of claim 1, Compressor oil supply device, characterized in that the inner lower portion of the compressor case is further provided with a compression chamber oil injection means for injecting oil returned to the inside of the compressor case through the oil return pipe into the compression chamber. The method of claim 3, wherein The compression chamber oil injection means An injection tube having one end connected to the oil return tube and the other end inserted into a coupling hole formed in a lower bearing; The coupling hole and the compression chamber is formed in the lower bearing in communication with the opening and closing by opening or closing by the lower surface by the movement of the roller as an oil supply hole for injecting oil into the compression chamber, Oil supply device of the compressor, characterized in that configured. The method of claim 4, wherein The injection tube The oil supply apparatus of the compressor, which is fixed to one side of the compressor case and connected to an oil supply pipe on one side, and inserted into a guide tube having a larger diameter than the injection pipe to form a double pipe shape. An oil tank provided at one side of the compressor case and having a predetermined space for storing oil therein; An oil supply pipe connected to one end of the compressor case so as to communicate with the inside of the compressor case and the other end connected to the oil tank to supply excess oil in the compressor case to the oil tank; One end is connected to the oil tank and the other end is connected to the inlet of the accumulator to return the oil in the oil tank to the accumulator, Oil supply device of the compressor, characterized in that configured. An oil tank provided at one side of the compressor case and having a predetermined space for storing oil therein; A first supply pipe connected to one end of an upper end of the oil tank and connected to a discharge pipe installed at an upper end of the compressor case to supply refrigerant and oil discharged to the discharge pipe to an oil tank; A second supply pipe having one end connected to the other end of the upper end of the oil tank and the other end connected to a condenser to supply only refrigerant gas from the oil tank to the condenser; One end is connected to the lower end of the oil tank and the other end is connected to the side of the compressor case is an oil return pipe for returning the oil stored in the oil tank to the inside of the compressor case, Oil supply device of the compressor, characterized in that configured.

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