KR100308289B1 - Protection device of a scroll compressor - Google Patents

Abstract

The present invention relates to a protection device of a scroll compressor, and the conventional scroll compressor is to protect the compressor by opening the pressure valve under the abnormal pressure condition due to overcompression, but the pressure when the suction side vacuum occurs due to a blocked cycle, etc. Since the pressure valve does not operate because the difference is not large, there are many problems such as the damage of the motor due to the vacuum and the function of the compressor to stop, and the difficulty of attaching the pressure valve causes leakage to the attachment site. Bar, the present invention is equipped with a protection means for adjusting the pressure difference between the discharge pressure and suction pressure and the operating range of the set pressure in the fixed scroll during high compression or vacuum compression to the fixed scroll over compression or during operation of the scroll compressor High-temperature, high-pressure refrigerant that flows back into the low pressure chamber when vacuum compression occurs Controlling the switch it is possible to efficiently compressor can always be in a safe condition protection to perform the normal operation according to improve the service life and operating efficiency of the compressor.

Description

PROTECTION DEVICE OF A SCROLL COMPRESSOR}

The present invention relates to a protection device for a scroll compressor, and more particularly, to protect the compressor in a safe state when overcompression or vacuum compression occurs in the scroll compressor.

In the conventional conventional scroll compressor, as shown in FIG. 1, main and lower frames 15 and 16 are respectively installed on upper and lower portions of the sealed container 1 having a predetermined internal volume, and the main and lower frames are respectively. The stator 17a and the rotor 17 which form the motor 14 are installed between the 15 and the 16, and interlocked with the rotation of the rotor 17 through the center of the rotor 17. An eccentric portion 19 is formed at the upper end of the crankshaft 18 installed so that the eccentric portion 19 is inserted into the eccentric portion 19 is inserted into the slide bush 20 which is radially variable and receives the rotational force of the crankshaft 18 in the tangential direction. do.

In addition, a fixed scroll 2A having an involute wrap 2a is fixed on the main frame 15, and a compression movement while sliding with the slide bush 20 is applied to the wrap 2a formed on the fixed scroll 2A. The wrap 10a of the swinging scroll 10 is pivotally engaged so that the lower portion of the swinging scroll 10 is inserted into the eccentric portion 19 of the crankshaft 18. It is coupled to, and the old dam ring 21, which is a rotation prevention mechanism for preventing the rotation of the swinging scroll 10 is coupled between the lower surface of the swinging scroll 10 and the upper surface of the main frame 15.

The high and low pressure separating plate 12 separating the inside of the sealed container 1 into a high pressure portion and a low pressure portion is coupled to the upper surface of the fixed scroll 2A in the sealed container 1 by a plurality of bolts 22. The check valve 23 and the valve housing 24 for controlling the flow of the high-temperature and high-pressure refrigerant gas compressed in the pocket space, which is a compression space, are coupled to the center of the high and low pressure separator plate 12. ), A suction pipe 25 and a discharge pipe 13 through which the refrigerant gas is sucked and discharged are provided, and a discharge port 11 is formed in the center of the fixed scroll 2, and The lower portion is configured to be filled with the oil supplied to the sliding portion.

Operation of the scroll compressor including each component as described above, first, when the rotor 17 of the motor 14 is rotated by the applied current, by the rotation of the rotor 17 crank shaft ( As the 18 rotates, the orbiting scroll 10 is rotated, i.e., orbited, with the eccentric distance of the eccentric portion 19 as a radius.

The pivoting scroll 10 is pivoted by drawing a pivot member at a distance separated by a turning radius while the rotation of the pivoting mechanism is prevented by the Old Daming 21 which is a rotation prevention mechanism. By the swinging movement of the swinging scroll 10 a pocket, which is a compression space, is formed by the laps 2a and 10a of the fixed and swinging scrolls 2A and 10, which pocket is centered by a continuous swinging movement. While moving, the volume is reduced to compress the sucked refrigerant gas and is discharged through the discharge port 11 of the fixed scroll 2A.

The refrigerant gas in the high temperature and high pressure state compressed in the pocket formed by the laps 2a and 10a of the fixed and swing scrolls 2A and 10 by the swinging movement of the swing scroll 10 is discharge port of the fixed scroll 2A. It is discharged through the (11) is introduced into the high pressure portion through the high and low pressure separating plate 12 that divides the high pressure portion and the low pressure portion, the refrigerant gas introduced into the high pressure portion flows into the condenser (not shown) through the discharge pipe (13). do.

When the scroll compressor stops operation for a while and then operates again, the gas of the high pressure part flows back to the low pressure part and the wrap 2a of the fixed and swinging scrolls 2A and 10 through the discharge port 11 ( It is introduced into the inside of the pocket formed by 10a) and rotates the revolving scroll 10 reversely, thereby causing breakage and noise of the wraps 2a and 10a, as well as high and low pressure separation to prevent the compression efficiency from being lowered. The check valve 23 and the valve housing 24 provided on the plate 12 serve to prevent the gas of the high pressure portion from flowing back to the low pressure portion.

On the other hand, since the pressure valve 26 is mounted on one side of the high and low pressure separating plate 12, when the discharge pressure is abnormally high, that is, the pressure valve 26 is opened only in overcompression and the refrigerant in the high pressure chamber H is opened. The overload protection device (not shown) attached to the motor 14 is operated so that the gas flows back into the low pressure chamber L to protect the compressor.

However, in the conventional scroll compressor, the pressure valve 26 is opened to protect the compressor under abnormal pressure conditions caused by overcompression, but the pressure difference is not large when the suction side vacuum is generated due to a blocked cycle. Since the 26 is not operated, the vacuum 14 burns out of the motor 14 and the function of the compressor is stopped, and the pressure valve 26 is difficult to attach, causing leakage to the attachment site. There were many problems.

Accordingly, the present invention is to solve the above-mentioned problems, the compressor can always perform the normal operation by efficiently controlling the high-temperature and high-pressure refrigerant gas flow back to the low pressure chamber when over-compression or vacuum compression occurs in the scroll compressor It is an object of the present invention to provide a protection device for a scroll compressor that can be protected in a safe state.

1 is a vertical cross-sectional view showing a conventional scroll compressor.

2 is a longitudinal sectional view showing a scroll compressor according to the present invention.

3 is a detailed view of portion A of FIG.

4 is a front view showing a safety valve according to the present invention

5A and 5B are longitudinal cross-sectional views each showing an operating state at normal pressure load and overcompression or vacuum compression of the scroll compressor according to the present invention;

Explanation of symbols on the main parts of the drawings

2; Fixed scroll 3; Means of protection

4; Receiving groove 5; Through

6; Guide 7; Plate valve

8; Elastic member 9; Stopper

H; High pressure chamber L; Low pressure chamber

In order to achieve the above object, the present invention provides a crankshaft interlocked with a rotor of a motor in an airtight container, and a fixed scroll having an involute-shaped wrap formed on an upper portion of the main frame is fixed and formed on a fixed scroll. The wrap is provided with a compression mechanism unit provided to pivotally engage the lap of the swinging scroll, which slides and slides in compression, and has a high pressure chamber on the upper side and a low pressure on the lower side by the high and low pressure separating plate installed at the upper portion of the scroll. In the scroll compressor in which the seal is formed, the suction pipe is connected to the low pressure chamber, and the discharge pipe is connected to each of the high pressure chamber, the accommodating groove and the accommodating groove formed on one side of the fixed scroll and having an outer end communicating with the low pressure chamber. A guide hole communicating with the high pressure chamber, a plate-shaped valve installed in the receiving groove to open and close the guide hole, and the plate. It provides a protective device for a scroll compressor comprising a protective means composed of an elastic member for elastically supporting the type valve in the normally closed direction.

The protection means is installed at the rear end of the receiving groove is characterized in that it further comprises a stopper for preventing the separation of the plate-shaped valve and the elastic member.

The plate valve is characterized in that the thermocouple.

The opening of the high pressure chamber side is smaller than the opening of the low pressure chamber side.

Hereinafter, preferred embodiments of the present invention for achieving the above object will be described in detail with reference to the accompanying drawings.

Figure 2 is a longitudinal sectional view showing a scroll compressor according to the present invention, Figure 3 is a detailed view of the portion A of Figure 2, Figure 4 is a front view showing a safety valve according to the invention, Figures 5a and 5b The longitudinal cross-sectional view which shows the operating state at the time of a normal pressure load and overcompression or vacuum compression of the scroll compressor which concerns on this, and attaches | subjects the same code | symbol about the same part as a prior art, and demonstrates this invention.

According to the present invention, the pressure difference between the discharge pressure and the suction pressure and the set pressure are operated inside the fixed scroll (2) during high compression or vacuum compression on the upper side of the fixed scroll (2) installed at the upper part in the sealed container (1) of the scroll compressor. Equipped with protective means 3 which operate to adjust the range.

The protection means (3) is installed in front of the receiving groove (4) formed on the upper side of the fixed scroll (2) to form a plurality of through holes (5) for communicating the high pressure chamber (H) and the low pressure chamber (L) A plate-shaped valve 7 made of a thermocouple to open and close the guide hole 6, a spring-like elastic member 8 installed in the receiving groove 4 to impart an elastic restoring force during operation of the plate-shaped valve 7; It is installed in the rear end of the receiving groove 4 is composed of a stopper (9) for preventing the separation of the plate-shaped valve (7) and the elastic member (8), in this case, the opening of the high-pressure chamber (H) side Is formed smaller than the opening part on the low pressure chamber L side.

The present invention configured as described above is formed between the wraps 2a and 10a of the fixed and swinging scrolls 2 and 10 installed inside the sealed container 1 of the scroll compressor, as shown in FIGS. The refrigerant gas of the high temperature and high pressure compressed by the interaction of the fixed and swinging scrolls 2 and 10 inside the compression chamber C is fixed scroll 2 through the discharge port 11 of the fixed scroll 2. Passed through the high and low pressure separation plate 12 of the upper portion is supplied to the refrigeration cycle through the discharge tube 13 of the upper side of the closed container (1).

At this time, when the intake gas does not flow due to the abnormality of the refrigeration cycle (clogging of the pipe), the low pressure chamber (L) is in a vacuum state, but the vacuum state reaches only about 10 to 30 seconds as a result of the experiment.

The operating principle of the vacuum state is a plate-shaped valve which is installed in front of the receiving groove 4 formed on the upper side of the fixed scroll 2 constituting the protection means 3 mounted on the upper side of the fixed scroll 2. The force exerted on (7), that is, the force exerted by the discharge pressure Fd = PdA1, where A1 is the cross-sectional area of the guide hole 6 communicating the high pressure chamber H and the low pressure chamber L, and Pd is the discharge pressure. And a force Fc = k * X, where k is a spring constant and X is a spring constant, provided by the spring-like elastic member 8 to provide elastic restoring force during operation of the plate valve 7. Distance, the force exerted by the suction pressure Fs = Ps A2, where Ps is the suction pressure, and A2 is the cross-sectional area of the plate-shaped valve 7, where the cross-sectional value is a plurality of through holes 5 in the plate-shaped valve 7. Subtracted, the above equation can be defined by this principle since the pressure P acts on the force F acting per unit area (A = π / 4 · d 2).

As described above, the force exerted by the discharge pressure on the plate valve 7 and the force exerted by the elastic member and the force exerted by the suction pressure are as follows by the balance of the forces.

That is, when the force exerted by the discharge pressure is greater than the sum of the force exerted by the elastic member and the force exerted by the suction pressure (Fd> Fc + Fs), the over-compression in which the discharge pressure is excessively increased or the vacuum compression is too low in suction pressure When the force exerted by the discharge pressure is less than the sum of the force exerted by the elastic member and the force exerted by the suction pressure (Fd < Fc + Fs), the discharge pressure and the suction pressure are within the set pressure range. to be.

Therefore, the diameter of the guide hole 6 communicating the variable high pressure chamber H and the low pressure chamber L, the through hole 5 of the plate valve 7, and the plate valve 7 so as to satisfy the above conditions. It is preferable to manufacture the present invention by determining the diameter, the spring constant of the elastic member 8 and the displacement X.

That is, when the scroll compressor, which is a normal pressure load characteristic, operates normally, the force exerted by the discharge pressure on the valve 7 is smaller than the sum of the force exerted by the elastic member and the force exerted by the suction pressure (Fd <Fc). + Fs), the plate-shaped valve 7 closes the guide hole 6 communicating the high pressure chamber H and the low pressure chamber L, as shown in FIG. 5A, so that the discharge pressure of the high pressure chamber H is increased. Since a phenomenon in which the flow back to the low pressure chamber (L) does not occur, a pressure drop does not occur.

In addition, in the case of abnormal pressure load characteristics, i.e., when the scroll compressor is overcompressed or vacuum compressed, the force exerted by the discharge pressure on the valve 7 is greater than the sum of the force exerted by the elastic member and the suction pressure. Fd &gt; Fc + Fs), the plate valve 7 retracts to open the guide hole 6 as shown in FIG. 5B, so that the discharge pressure passes through the plurality of through holes 5 of the plate valve 7. In this case, the high temperature and high pressure refrigerant gas flows back to the low pressure chamber (L) to stop the compressor by operating the overload protection device attached to the motor 14 so that the compressor can be safely protected when overcompression or vacuum compression occurs. Will be.

As described above, the present invention provides a safe state in which the compressor can always perform normal operation by efficiently controlling the high temperature and high pressure refrigerant gas flowing back to the low pressure chamber when overcompression or vacuum compression occurs during operation of the scroll compressor. It is a very useful invention that can greatly improve the efficiency and reliability of the device because it can increase the service life and operating efficiency of the compressor.

Although the preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the above-described embodiments, and the present invention may be commonly used in the technical field to which the present invention pertains without departing from the spirit of the present invention as claimed in the following claims. Anyone with knowledge will be able to make various changes.

Claims (4)

A crankshaft interlocked with the rotor of the motor is installed inside the sealed container, and a fixed scroll having an involute wrap is fixed to the upper part of the main frame, and a wrap formed on the fixed scroll performs compression movement while sliding with a slide bush. Compression mechanism is provided so that the lap of the swinging scroll is rotatably engaged, the high pressure chamber is formed on the upper side, the low pressure chamber is formed on the lower side by the high and low pressure separation plate installed on the upper portion of the scroll, the suction pipe is In the scroll compressor, the discharge pipe is connected to the high pressure chamber, An accommodation groove formed on one side of the fixed scroll and having an outer end communicating with the low pressure chamber, a guide hole for communicating the accommodation groove to the high pressure chamber, a plate valve installed in the accommodation groove to open and close the guide hole, and the plate shape. And a protection means composed of an elastic member for elastically supporting the valve in the normally closed direction. The protection device of a scroll compressor according to claim 1, wherein the protection means further comprises a stopper installed at the rear end of the accommodation groove to prevent separation of the plate valve and the elastic member. The protection device for a scroll compressor according to claim 1, wherein the plate valve is a thermocouple. The protection device for a scroll compressor according to claim 1, wherein the opening portion on the high pressure chamber side is smaller than the opening portion on the low pressure chamber side.