KR20000039131A - Apparatus for preventing superheating of scroll compressor - Google Patents

Abstract

PURPOSE: An apparatus for preventing superheating of a scroll compressor is provided to prevent oil from carbureting and a damage of the compressing machine part by promptly stopping the operation of the compressor when temperature abnormally rises in the compressor. CONSTITUTION: In a scroll compressor including an electric machine part having a stator and a movable part, a suction pipe for sucking a refrigerant, a fixed scroll and a rotary scroll compressing the refrigerant flew, an upper diaphragm(1) supporting the fixed scroll and defining a suction room and a discharging room(8), and a discharging pipe discharging the refrigerant of the discharging room(8) to the outside, an apparatus for preventing superheating of a scroll compressor includes a thermal valve(101) installed in a front end of the discharging pipe(18) to be opened and closed according to the fluctuation of the refrigerant temperature, a differential pressure valve(102) installed in a proper position of the upper diaphragm to open and close the discharging room and the electric machine part for being opened and closed according to the difference of pressure between the discharging room and the suction room, and an apparatus for protecting overload(20) installed in a proper position for breaking power supply applied to the electric machine part if the refrigerant flows in due to the opening of the differential pressure valve(102), thereby stopping operation.

Description

Overheat prevention device of scroll compressor

The present invention relates to a scroll compressor for compressing a refrigerant by a swing action between a fixed scroll and a swing scroll, and more particularly, to an overheat prevention device for minimizing the effect of heat generated during a refrigerant compression process on a compressor mechanism.

In general, a scroll compressor is a device that compresses a refrigerant by using a rotational force by an axis by interposing a refrigerant in a compression chamber of an involute curve wrap formed between a fixed scroll and a rotating scroll, and has a larger capacity than other compressors. It is well known that it is mainly used in an air conditioner and a freezer because it has excellent dynamic performance in the range of.

Such a scroll compressor will be described taking the apparatus shown in FIG. 1 as an example.

The overall configuration of the scroll compressor is linked to the upper and lower shells (2) (2a), the rotor (3) and the stator (4), the electric mechanism part, the electric mechanism part divided through the upper diaphragm 1 as shown in FIG. Compressor spout consisting of the revolving scroll 6 and the fixed scroll 7, and the main shaft 5 for transmitting the rotational force generated from the power transmission mechanism to the compressor spout.

At this time, the upper portion of the diaphragm 1, the upper portion is composed of the discharge chamber (8), the lower portion is composed of the suction chamber (9), the upper diaphragm (1) and the separation that separates the suction chamber (9) and the discharge chamber (8) The refrigerant compressed by the compression mechanism portion is sent to the discharge chamber 8 through the check valve 10 provided between the scrolls 7.

Therefore, the pressure distribution inside the compressor shell 2 (2a) is such that the suction chamber 9 through which the refrigerant flows through the suction pipe 11 becomes the low pressure side, and the upper shell 2 flows through the compression mechanism. The discharge chamber 8 forms a relatively high pressure side.

The refrigerant flowing through the suction pipe 11 is sucked into the compression chamber of the involute curve wrap formed on the fixed scroll 7 and the swing scroll 6, and the rotor 3 of the electric mechanism rotates. Rotating the spindle 5 is connected to the swing frame 6 and the one-way keyway by the old dam ring 14 on the upper frame 12 and the drive bushing 13 to rotate the rotation of the spindle 5 Will be transformed into a turning movement.

The refrigerant compression process according to the turning angle of the turning scroll 6 is shown in FIG. 2. Where A is the direction of rotation and S1 is the center of rotational movement = spindle center = fixed scroll center.

When the swing scroll lap forms a suction flow path away from the outer lap of the fixed scroll at 0 °, the refrigerant flows through the two semi-moon compression chambers formed by the two scroll wraps to the center of the scroll, depending on the swing angle. Proceed.

Eventually, the compression chamber collected at the center is opened at the discharge port 15 on the rear of the fixed scroll 7, and the compressed refrigerant discharged through the valve housing 16 is mounted on the fixed scroll 7. ) Is pushed upward and discharged into the discharge chamber 8 composed of the upper diaphragm 1 and the upper shell 2, and the refrigerant compressed through the discharge pipe 18 is sent to a freezing / air conditioning cycle.

Here, it is apparent that a pressure difference is generated in the suction chamber and the discharge chamber, but when the difference becomes larger than the set pressure, the compressor is subjected to a considerable load, thereby raising the temperature of the refrigerant to be compressed.

When the oil film is broken in the part between the fixed scroll and the turning scroll by this heat, the fixed scroll and the turning scroll are operated while making metal contact, and high heat is generated in this area, and the oil is carbonized and the fixed scroll and the turning scroll are pressed together. Can cause the compressor to become inoperable.

In order to solve this problem, U.S. Patent 5,707,210 installs a thermal valve 19 at the discharge port 15 of the fixed scroll 7 and OLP (overload protection device) mounted on the stator 4 as shown in FIG. A method of connecting the gas pipe 21 between the over load protection (20) and the thermal valve (19) has been proposed.

That is, when the temperature of the discharged refrigerant rises above the set temperature, the thermal valve 19 is opened. Accordingly, the hot discharge refrigerant flows into the OLP 20 through the gas pipe 21 and the OLP 20 is driven by the electric mechanism part. Shut off the power applied to the compressor to stop.

In addition, one side of the upper diaphragm 1 is provided with a differential pressure valve to communicate with the OLP (20).

The differential pressure valve is opened when the pressure of the refrigerant in the discharge chamber 8 is greater than or equal to the set value, thereby allowing the high pressure refrigerant to flow into the OLP 20 to perform the same role as the above-described thermal valve 19.

However, in installing the secondary valve in the discharge port in this way, this method requires a very precise and complicated processing on the fixed scroll back and the discharge port, there is a problem that the productivity is lowered.

Therefore, a structure capable of creating an effect equivalent to that of the conventional one while preventing damage to the mechanism part of the compressor due to heat of the discharged refrigerant is desirable.

Accordingly, the present invention has been proposed in view of this point, and if an abnormal temperature rise occurs in the compressor, the compressor may be stopped quickly to prevent overheating of the scroll compressor that prevents carbonization or components from sticking together. The object is to provide a prevention device.

In another aspect, the object is to improve the productivity by simplifying the structure for preventing overheating in the compressor.

1 is a longitudinal sectional view of a general scroll compressor,

2 is a refrigerant compression progress diagram of a typical scroll compressor,

3 is a diagram illustrating an overheat prevention device of a conventional scroll compressor;

Figure 4 is a block diagram of the overheat prevention device of the scroll compressor according to the present invention,

5 is a detailed view of the thermal valve according to the present invention;

Figure 5a is a valve open state,

5B is a valve closed state,

6 is a detailed view of the differential pressure valve according to the present invention;

6a shows the valve is closed,

6B shows the valve open.

*** Explanation of symbols for main parts of drawing ***

1: upper diaphragm 2, 2a: upper, lower shell

3: rotor 4: stator

5: spindle 6: turning scroll

7: fixed scroll 8: discharge chamber

11 suction pipe 18 discharge pipe

20: overload protection device (OLP) 21: gas pipe

101: Thermal valve 101a: refrigerant discharge port

101b: bimetal diaphragm 102: differential pressure valve

102a: valve member 102b: spring

An apparatus for preventing overheating of a scroll compressor according to the present invention for achieving the above objects includes: a power mechanism unit including a stator and a rotor, a suction pipe for sucking refrigerant, and a fixed scroll and a rotating scroll for compressing the refrigerant introduced through the suction pipe. A scroll compressor comprising: an upper diaphragm for supporting the fixed scroll and partitioning a suction chamber and a discharge chamber; and a discharge pipe for discharging the refrigerant in the discharge chamber to the outside.

(1) discharge control means provided at a tip of the discharge pipe to open and close according to a coolant temperature rise in the discharge chamber;

(2) selective discharging means installed at a position of the upper diaphragm so as to open and close the discharge chamber forming the high pressure portion and the power mechanism portion forming the low pressure portion and being opened and closed according to the pressure difference between the discharge chamber and the suction chamber; And

And (3) an operation stop means installed at a location in the suction chamber to stop the operation by shutting off the power applied to the stator when the refrigerant flows in accordance with the opening of the selective discharge means.

Preferably, the discharge control means is a thermal valve that reacts according to the temperature of the refrigerant.

Preferably, the thermal valve is characterized by consisting of a valve member for opening and closing the inlet of the discharge pipe.

Optionally, the valve member is characterized by consisting of a bimetal diaphragm composed of two or more materials having different thermal expansion rates.

Preferably, the selective discharge means is characterized in that the differential pressure valve reacts according to the pressure difference between the discharge chamber and the suction chamber.

Preferably, the differential pressure valve is characterized by consisting of a valve member for opening and closing the refrigerant inlet according to the pressure difference between the discharge chamber and the suction chamber, and an elastic member for elastically supporting the valve member.

Optionally, the valve member is configured to have a spherical shape having a diameter larger than that of the refrigerant inlet.

Preferably, the gas pipe constituting the transfer passage of the refrigerant is installed between the selective discharge means and the operation stop means.

In this way, the compressor can be quickly stopped when the refrigerant in the compressor is overheated.

As a result, deterioration of the lubricating film between the fixed scroll and the turning scroll can be prevented from being in contact with each other, and oil can be prevented or the phenomenon in which the fixed scroll and the turning scroll are pressed together can be prevented.

In addition, the configuration of the overheat prevention device has the advantage that it is easy to install by using a differential pressure valve installed in the existing can improve the productivity.

And, there may be a plurality of embodiments of the present invention, hereinafter will be described in detail with respect to the most preferred embodiment.

This preferred embodiment allows for a better understanding of the objects, features and advantages of the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the overheat prevention device of the scroll compressor according to the present invention.

In addition, the technology of the present invention can be applied to various scroll compressor products applied to an air conditioner or a refrigerator.

Thus, the figures used in the description are not specific scroll compressor products, but focus on general scroll compressors.

In addition, in drawing used for description, about the component same as FIG. 1 and FIG. 3, the same code | symbol is attached | subjected, and the overlapping description may be abbreviate | omitted.

Figure 4 is a block diagram showing an embodiment provided in the description of the overheat prevention device of the scroll compressor according to the present invention, Figure 5 is a detailed view of the thermal valve according to the present invention, Figure 5a is a valve open state, 5b is a closed state of the valve, Figure 6 is a detailed view of the differential pressure valve according to the present invention, Figure 6a is a state in which the valve is closed, Figure 6b shows a state in which the valve is open.

The overheat prevention apparatus of the scroll compressor according to the present embodiment is for preventing the deterioration of the mechanism part by stopping the operation of the compressor when the refrigerant temperature in the compressor is overheated. As shown in FIG. 4, the refrigerant temperature inside the discharge chamber 8 is normal. The discharge chamber, which is a high pressure part, is opened by the pressure rise of the thermal valve 101 installed at the tip of the discharge pipe 18 and the discharge chamber 8 when the thermal valve 101 is closed, so that the valve is opened in the state and closed when the temperature is higher than the set temperature. 8) The differential pressure valve 102 installed at an arbitrary position of the upper diaphragm 1 so as to discharge the superheated refrigerant in the low pressure portion to the motor mechanism side, and the differential pressure valve 102 is opened and applied to the electric mechanism when the superheated refrigerant flows in. It is composed of an overload protection device 20 mounted on the stator (4) to shut off the power supply to stop the operation of the compressor.

At this time, the thermal valve 101 is a means for controlling the discharge of the refrigerant, the refrigerant discharge port 101a for discharging the refrigerant as shown in Figure 5 and two or more kinds of thermal expansion coefficient of the material is different from the discharge pipe 18 It consists of the valve member which consists of the bimetal diaphragm 101b which opens and closes an inlet part.

In addition, the differential pressure valve 102 is a means for selectively discharging the refrigerant according to the opening and closing of the thermal valve 101, and uses a differential pressure valve having a conventional structure for the same purpose, and its structure is smaller than the diameter of the refrigerant inlet as shown in FIG. A spherical valve member 102a having a large diameter and a spring 102b that elastically supports the valve member 102a.

In addition, the overload protection device 20 is a means for stopping the operation of the compressor by operating by the inflow of the superheated refrigerant in accordance with the opening of the differential pressure valve 102, also using the conventional overload protection (OLP) for the same purpose will be.

Here, the gas pipe 21 is preferably provided between the differential pressure valve 102 and the overload protection device 20 in order to smoothly transfer the superheated refrigerant discharged through the differential pressure valve 102 to the overload protection device 20. Do.

The overheat prevention device of the scroll compressor according to the present invention made as described above operates as follows.

First, the suction, compression, and discharge processes of a general refrigerant proceed in the same manner as in the prior art.

At this time, when the temperature of the compressed refrigerant discharged to the discharge chamber 8 is normal, the discharge is performed in a refrigerating or air conditioning cycle in the same manner as the discharge process of the general refrigerant. That is, the thermal valve 101 at the tip of the discharge pipe 18 is kept open and does not interfere with the discharge of the refrigerant, and the differential pressure valve 102 has a pressure in the discharge chamber 8 that the thermal valve 101 is opened. As it maintains the normal state, it is kept closed.

In this state, if the temperature of the compressed refrigerant is overheated above the set temperature, the thermal valve 101 at the tip of the discharge pipe 18 responds to the temperature of the refrigerant, so that the bimetal diaphragm 101b enters the inlet of the discharge pipe 18. The discharge pipe 18 is closed as it is bent in the direction of closing the part, and as the discharge pipe 18 is closed, the pressure in the discharge chamber 8 rapidly rises to a predetermined pressure or more, for example, a spring of the differential pressure valve 102 ( 102b) When the elastic force and the suction pressure are equal to or more than the numerical values, the spherical valve member 102a of the differential pressure valve 102 is spaced apart and opened from the refrigerant inlet, and the superheated refrigerant is discharged to the power mechanism part forming the low pressure side.

The discharged superheated refrigerant reaches the overload protection device 20 along the gas pipe 21, and heats the overload protection device 20 to drive the overload protection device 20. That is, the overload protection device 20 is to cut off the power applied to the transmission mechanism to stop the operation of the compressor.

Accordingly, when the superheated refrigerant is generated in the compressor, the compressor is quickly shut off, thereby preventing carbonization of the oil and damage to the compression mechanism due to the heat.

On the other hand, as a comparative example, unlike the conventional technology, that is, the refrigerant flow path for introducing the superheated refrigerant into the overload protection device using a very precise and complicated processing method in the discharge port of the fixed scroll, the present invention is a relatively simple method, That is, it can be seen that a method of installing a valve at the tip of the discharge pipe and in place of the upper diaphragm is used to discharge the refrigerant to the discharge chamber first and then control the discharge of the refrigerant according to the refrigerant temperature and pressure in the discharge chamber.

As a result, according to the present invention, it is obvious that the performance and the life of the compressor are extended as compared with the case where the overheat protection device is not installed. However, the present invention is simpler than the flow path configuration of the overheat protection device via the discharge port of the fixed scroll. There is an advantage that can greatly increase the productivity by the installation method.

In addition, although specific embodiments of the present invention have been described and illustrated above, it is obvious that the present invention may be variously modified and implemented by those skilled in the art.

Such modified embodiments should not be individually understood from the technical spirit or the prospect of the present invention, and such modified embodiments should fall within the appended claims of the present invention.

It is clear from the above description that according to the present invention, when an abnormal temperature rise occurs in the compressor, it is possible to quickly stop the operation of the compressor to prevent the oil from carbonizing or the fixed scroll and the turning scroll press against each other. In the installation of the connection passage for introducing into the protective device can be configured in a simple way compared to the conventional method is that the productivity is improved.

Claims (8)

Electric mechanism consisting of a stator and a rotor, a suction pipe for sucking the refrigerant, a fixed scroll and a rotating scroll for compressing the refrigerant introduced through the suction pipe, the upper diaphragm to support the fixed scroll and partition the suction chamber and the discharge chamber In the scroll compressor comprising a discharge pipe for discharging the refrigerant in the discharge chamber to the outside: (1) discharge control means provided at a tip of the discharge pipe to open and close according to a coolant temperature rise in the discharge chamber; (2) selective discharging means installed at a position of the upper diaphragm so as to open and close the discharge chamber forming the high pressure portion and the power mechanism portion forming the low pressure portion and being opened and closed according to the pressure difference between the discharge chamber and the suction chamber; And (3) Overheat prevention device of the scroll compressor including a stop operation means is installed in place of the suction chamber to stop the operation when the coolant flows in accordance with the opening of the selective discharge means to stop the operation. The method of claim 1, And the discharge control means is a thermal valve reacting according to the temperature of the refrigerant. The method of claim 2, The thermal valve is overheat prevention device of the scroll compressor, characterized in that consisting of a valve member for opening and closing the inlet of the discharge pipe. The method of claim 3, wherein The valve member is overheat prevention device of the scroll compressor, characterized in that consisting of a bimetal diaphragm consisting of two or more materials having different coefficients of thermal expansion. The method of claim 1, And the selective discharge means is a differential pressure valve reacting according to a pressure difference between the discharge chamber and the suction chamber. The method of claim 5, The differential pressure valve is a overheat prevention device of a scroll compressor, characterized in that consisting of a valve member for opening and closing the refrigerant inlet according to the pressure difference between the discharge chamber and the suction chamber, and an elastic member for elastically supporting the valve member. The method of claim 6, The valve member is overheat prevention device of the scroll compressor, characterized in that formed in a sphere (sphere) having a diameter larger than the diameter of the refrigerant inlet. The method of claim 1, And a gas pipe constituting a conveyance passage of the refrigerant is provided between the selective discharge means and the stop operation means.