JP2005264752A - Scroll compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scroll compressor having a high and low pressure bypass mechanism capable of maintaining the accuracy of the tilt of a bearing in assembly by suppressing the reversal of high and low pressures in a closed container in airtight test and when a refrigerant is sealed therein to eliminate the displacement of a frame. <P>SOLUTION: This scroll compressor comprises a chamber 22 having a communication hole 25 formed in a fixed scroll 1 for communicating an intake pressure atmosphere low pressure space 23 with a high pressure space 24 and a muffler chamber 21 having a delivery valve 20 disposed on the opposite side of the swing scroll 3 side of a fixed scroll so as to cover a part of the communication hole and communicating or cutting off a compression space and a high pressure space with or from each other and allowed to communicate with the compression chamber from the delivery port of the fixed scroll to the delivery valve, a valve seat 31 formed at the lower part of the communication hole, and a ball valve 26 stored in the communication hole, closely fitted to the valve seat when the communication hole is closed to close the communication hole, and separating from the valve seat when the communication hole is opened to suppress the movement thereof into the high pressure chamber by the chamber. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a scroll compressor having a high-pressure space and a low-pressure space in an airtight container used for a refrigeration air conditioner.

  In a conventional scroll compressor equipped with a high / low pressure bypass mechanism, a temperature-sensitive valve such as a bimetal or a shape memory alloy or a valve made of Swedish steel, which is a general valve material, is used as a bypass valve. (For example, refer to Patent Document 1).

JP-A-3-237286 (FIG. 1)

  In a conventional scroll compressor equipped with a high and low pressure bypass mechanism, a bypass valve mechanism using a temperature-sensitive valve such as a bimetal or a shape memory alloy or a valve made of Swedish steel, which is a general valve material having rigidity. When the collision speed to the valve seat provided in the fixed scroll is high, there is a problem that the valve tip portion is cracked or the valve root portion is damaged. In addition, the number of parts increases, and it is necessary to pay attention to the assembly accuracy during valve assembly.

  The present invention has been made to solve the above-described problems, and a first object is to suppress the reversal of high and low pressures in a hermetic container during an airtight test or when a refrigerant is sealed, thereby eliminating frame misalignment. Thus, a scroll compressor having a highly reliable high and low pressure bypass mechanism capable of maintaining the inclination accuracy of the bearing at the time of assembly is obtained.

  The second object is to provide a scroll compressor equipped with a high and low pressure bypass mechanism that does not require expensive valve material, does not require bimetal setting for each mounted unit, reduces the number of parts, and is easy to assemble. To get.

  A scroll compressor according to the present invention includes a sealed container, a compression element that is disposed in the sealed container and includes a fixed scroll and a swing scroll, and a frame that is shrink-fitted and fixed in the sealed container to store the compression element. The high-pressure refrigerant gas compressed by the compression element by the frame is partitioned into a high-pressure space and a low-pressure space in the suction pressure atmosphere, and the high-pressure space and the low-pressure space are communicated with each other through a communication hole provided in the fixed scroll. The fixed scroll has a discharge valve that is disposed on the side opposite to the swing scroll side of the fixed scroll so as to cover a part of the communication hole, and that communicates and blocks between the compression space and the high pressure space. A chamber having a muffler chamber communicating with a compression space from the discharge port to the discharge valve, a valve seat provided at a lower portion in the communication hole, and housed in the communication hole When the communication hole is closed, the valve is seated in close contact with the valve seat to close the communication hole, and when the communication hole is opened, a ball valve that is separated from the valve seat and restrained from moving to the high-pressure space by the chamber is provided. Is.

The scroll compressor according to the present invention includes a communication hole provided in the fixed scroll that communicates the suction pressure atmosphere low-pressure space and the high-pressure space, and a side opposite to the swing scroll side of the fixed scroll so as to cover a part of the communication hole. A chamber having a discharge valve for communicating and blocking between the compression space and the high-pressure space and having a muffler chamber communicating with the compression space from the discharge port of the fixed scroll to the discharge valve; The valve seat provided in the lower part is housed in the communication hole, and when the communication hole is closed, it is placed in close contact with the valve seat to close the communication hole, and when the communication hole is opened, it is separated from the valve seat by the chamber. Since it has a ball valve that is prevented from moving to the high-pressure space, the low-pressure space is used to seal dry air and nitrogen gas for airtight testing during compressor manufacture and assembly into the compressor unit. The high-pressure space can be bypassed by a ball valve, and even if it is sealed quickly in a short time, it can prevent the frame from shifting, and it can be quickly extracted in a short time when extracting dry air and nitrogen gas after the airtight test. However, a highly reliable scroll compressor that can prevent frame misalignment can be obtained by shortening the manufacturing time.
Further, the frame can be prevented from being misaligned even when the refrigerant is enclosed in the unit, even if the refrigerant is enclosed rapidly in a short time.

Embodiment 1 FIG.
FIG. 1 is a longitudinal sectional view of a main part of a scroll compressor according to Embodiment 1 for carrying out the present invention, and FIGS. 2 and 3 are longitudinal sectional views of a valve portion showing the operation of a ball valve.
In the figure, reference numeral 1 denotes a fixed scroll having a spiral portion, 2 denotes a discharge hole formed substantially at the center of the fixed scroll 1, 3 denotes an orbiting scroll having a spiral portion, and 4 denotes an anti-rotation of the orbiting scroll 3. An Oldham ring that gives a swinging motion, 5 is a thrust bearing that receives the thrust load of the swing scroll 3, 6 is a crankshaft that transmits the driving force of the motor element, and 7 is an oil hole formed in the center of the crankshaft 6. , 8 is a main frame that supports the Oldham ring 4 and the thrust bearing 5 and is provided at the top. Reference numeral 9 denotes a sub-frame that supports a bearing 29 that receives the lower end of the crankshaft 6 and is provided at the lower part. Reference numeral 10 denotes a balance weight provided on the crankshaft 6. The components indicated by the above reference numerals 1 to 10 are compression elements of the scroll compressor. Reference numeral 11 denotes a stator, and 12 denotes a rotor. These components are electric motor elements. The compression element and the electric motor element are accommodated in the sealed container 13.
The main frame 8 in the compression element extends from the direction of the high-pressure space 24 to the step portion 30 formed in the upper inner periphery of the sealed container 13, and the subframe 9 is hermetically sealed from the lower side of the low-pressure space 23 to the inner wall of the sealed container 13. To be joined. A discharge muffler 14 is provided in the high-pressure space 24, and a chamber 22 having a discharge valve 20 and a muffler chamber 21 is disposed above the fixed scroll 1. The main frame 8 and the fixed scroll 1 fastened to the main frame 8 divide the suction pressure chamber or low pressure space 23 and the discharge pressure chamber or high pressure space 24 in the vertical direction. A communication hole 25 is provided so as to bypass the high-pressure space 24. In addition, a ball valve 26 that is prevented from moving from the chamber 22 installed so as to cover a part of the communication hole to the high-pressure space 24 is accommodated in the communication hole 25. There is provided a valve seat 31 on which the ball valve 26 is placed in close contact. In addition, 15 is an oil return pipe, 16 is a discharge pipe for discharging discharge gas, 17 is a suction pipe for introducing suction gas, 18 is a lubricating oil for lubricating sliding parts such as compressor bearings, and 19 is the above-mentioned shaking. A compression chamber formed by a pair of spirals combined with each other of the moving scroll 3 and the fixed scroll 1, 27 is a refrigerant gas suction passage provided in the main frame 8, and 28 is a positive displacement pump driven by driving the crankshaft 6. Respectively.

  Next, the operation of the scroll compressor will be described. The main frame 8 and the sub frame 9 in the compression element are airtightly joined to the inner wall of the sealed container 13 by shrink fitting or the like. The motive power generated by the motor element constituted by the stator 11 and the rotor 12 is transmitted to the orbiting scroll 3 by the crankshaft 6, and is oscillated by the Oldham ring 4 that prevents the orbiting scroll 3 from rotating and imparts an orbiting motion. The volume of the compression chamber 19 formed by a pair of spirals of the rocking scroll 3 and the fixed scroll 1 formed by moving is changed, and the sealed container 17 is closed from the suction pipe 17 toward the inner periphery from the outer periphery of the spiral. The refrigerant gas sucked into the 13 low-pressure space 23 is sucked and compressed through the suction passage 27, and passes through the muffler chamber 21 of the chamber 22 from the discharge hole 2 formed almost at the center of the fixed scroll 1 as a high-temperature high-pressure discharge gas. , Passes through the discharge valve 20 installed in the high-pressure space of the chamber 22, is discharged into the discharge muffler 14, and then the high-pressure empty of the sealed container 13. Is discharged to the outside of the compressor through the discharge pipe 16 is discharged to 24. At that time, the lubricating oil 18 at the bottom of the hermetic container 13 is provided with an oil supply head by a positive displacement pump 28 driven by driving of the crankshaft 6 and is raised in the oil hole 7 of the crankshaft 6 and arranged in the sub-frame 9. After the sliding parts such as the bearing 29 and the bearing portion of the main frame 8 are lubricated, they are discharged into the low pressure space 23 of the sealed container 13 through the oil return pipe 15 and returned to the bottom of the sealed container 13.

In a normal stop state, that is, in a state where the low pressure space 23 and the high pressure space 24 are equalized, or in a normal operation state, that is, in a state where the pressure in the high pressure space 24 is higher than that in the low pressure space 23, as shown in FIG. Is in close contact with the lower valve seat 31 in the communication hole 25 and closes the bypass passage between the low pressure space 23 and the high pressure space 24 from the communication hole 25. In this state, the main frame 8 that divides the suction pressure chamber, that is, the low pressure space 23 and the discharge pressure chamber, that is, the high pressure space 24 in the vertical direction by the main frame 8 and the fixed scroll 1 fastened to the main frame 8 is shrink-fitted. Since it is pressed by the pressure difference from the direction, that is, from the upper side, toward the closed container step portion 30, the state at the time of assembly is always maintained.
Next, when the dry air or nitrogen gas or the like for the airtight test is sealed, when the dry air or nitrogen gas or the like after the airtight test is taken out or when the refrigerant is sealed, the discharge pipe 16 in the refrigerant circuit is more than the suction rod 17. Due to the small diameter and the fact that a check valve or the like is arranged at the extension of the discharge pipe 16 in the unit pipe, the pressure in the low-pressure space 23 is higher than the high-pressure space 24 when they are suddenly performed. It becomes a state. In this state, as shown in FIG. 3, a force that lifts the ball valve 26 upward from the lower side due to the reverse pressure difference between the low pressure space 23 and the high pressure space 24 acts, and the ball valve 26 has a lower valve seat 31 in the communication hole 25. And floats in the communication hole 25 to open a bypass passage between the low pressure space 23 and the high pressure space 24. The chamber 22 arranged so as to cover a part of the communication hole 25 prevents the ball valve 26 floating in the communication hole 25 from jumping out into the high-pressure space 24.

  As described above, when the pressure in the low pressure space 23 becomes higher than that in the high pressure space 24, a force that lifts the ball valve 26 upward from the lower side works due to the reverse pressure difference between the low pressure space 23 and the high pressure space 24. 26 is separated from the lower valve seat 31 in the communication hole 25, floats in the communication hole 25, and opens a bypass between the low pressure space 23 and the high pressure space 24, and a sudden reverse pressure difference is generated. Even if a force is applied to push the frame 8 upward, the refrigerant gas passes through the communication hole 25 and is bypassed from the low pressure space 23 to the high pressure space 24, so that the main frame 8 is not displaced and A scroll compressor provided with a highly reliable high and low pressure bypass mechanism capable of maintaining tilt accuracy can be obtained. In addition, the ball valve 26 communicates even if the high-low pressure relationship between the high-pressure space 24 and the low-pressure space 23 is reversed momentarily by suddenly enclosing or extracting the refrigerant gas during the airtight test. The main frame 8 is not displaced because the low pressure space 23 and the high pressure space 24 are bypassed by moving away from the lower valve seat 31 in the hole 25 and bypassing the low pressure space 23 and the high pressure space 24. The productivity of the scroll compressor can be improved. The same applies to the charging of the refrigerant gas, and the time for charging the refrigerant when mounted on the unit can be shortened, and the productivity of the unit can be improved.

Embodiment 2. FIG.
In the first embodiment, when the pressure in the low pressure space 23 becomes higher than that in the high pressure space 24, the force that lifts the ball valve 26 upward from the lower side works due to the reverse pressure difference between the low pressure space 23 and the high pressure space 24. The ball valve 26 is separated from the lower valve seat 31 in the communication hole 25, floats in the communication hole 25, and opens a bypass passage between the low pressure space 23 and the high pressure space 24. Therefore, even if a force is generated to push up the main frame 8 upward due to a sudden reverse pressure difference, the gas passes through the communication hole 25 and is bypassed from the low pressure space 23 to the high pressure space 24, so that the main frame 8 is displaced. It is possible to obtain a scroll compressor equipped with a reliable high and low pressure bypass mechanism that can maintain the bearing tilt system at the time of assembly. In the case where it is easy to do, Embodiment 2 in which the counterbore of the opening to the high-pressure space 24 of the communication hole 25 is enlarged will be described.
FIG. 4 is an enlarged cross-sectional view of the communication hole portion of the scroll compressor according to Embodiment 2 of the present invention. As apparent from FIG. 4, the depth of the opening of the communication hole 25 to the high-pressure space 24 from the upper end surface of the fixed scroll 1, that is, the lower end surface of the chamber 22, is slightly shallower than the radius of the ball valve 26. It is.

  As described above, since the depth of the counterbore of the opening to the high-pressure space 24 of the communication hole 25 is slightly shallower than the radius of the ball valve 26, the ball valve 26 floats in the communication hole 25. Even if the ball valve 26 floats until it touches the uppermost side, that is, the lower end surface of the chamber 22, the ball valve 26 can be obtained smoothly without being caught in the countersink of the opening, and the bypass passage can be obtained. In addition, the flow path area can be increased, the main frame 8 is less likely to be displaced, the time required for the airtight test can be shortened, and the productivity of the scroll compressor can be improved. The same applies to the charging of the refrigerant gas, and it is possible to further reduce the time for charging the refrigerant when it is mounted on the unit and to improve the productivity of the unit.

Embodiment 3 FIG.
In the first and second embodiments, the fixed scroll 1 is provided with the communication hole 25 so as to bypass the low-pressure space 23 and the high-pressure space 24, and is installed in the communication hole 25 so as to cover a part of the communication hole. A ball valve 26 whose movement from the chamber 22 to the high pressure space 24 is suppressed is accommodated, and the ball valve 26 is floated in the communication hole 25 by the differential pressure between the high pressure space 24 and the low pressure space 23 to close or open the bypass. However, Embodiment 3 which employs a configuration other than this will be described.
FIG. 5 is an enlarged cross-sectional view of the communication hole portion of the scroll compressor according to Embodiment 3 of the present invention. As apparent from FIG. 5, the stepped portion of the main frame 8 shrink-fitted portion of the sealed container 13 is provided not only at the lower stepped portion 30 but also at the upper portion of the main frame 8 as a stepped portion 30 a. The upper step portion 30a of the hermetic container 13 is smaller than the lower step portion 30, and when the main frame 8 is shrink-fitted, the upper step portion 30a becomes larger than the outer diameter of the main frame 8, The step portion 30 is smaller than the outer diameter of the main frame 8, and the main frame 8 stops at the lower step portion 30 of the hermetic container 13 during shrink fitting. After shrink fitting, the temperature of the upper step portion 30a of the sealed container 13 decreases and heat shrinks to become smaller than the outer diameter of the main frame 8, and the shrink fit portion of the main frame 8 is sandwiched between the upper and lower step portions 30a and 30 of the sealed container 13. Therefore, the movement in the up and down direction is not possible and the shift does not occur.

  As described above, the communication hole 25 is provided so as to bypass the low-pressure space 23 and the high-pressure space 24, and the lower step portion 30 and the upper step portion 30a of the sealed container are further provided. It is difficult to shift, and the time for the airtight test can be shortened, and the productivity of the scroll compressor can be improved. The same applies to the refrigerant gas filling, and the refrigerant filling time when mounted on the unit can be further shortened, and the productivity of the unit can be improved.

It is a longitudinal cross-sectional view of the principal part of the scroll compressor in Embodiment 1 of this invention. It is an enlarged view which shows the normal state of the scroll compressor in Embodiment 1 of this invention. It is an enlarged view which shows the state at the time of refrigerant | coolant enclosure of the scroll compressor in Embodiment 1 of this invention. It is a cross-sectional enlarged view of the communicating hole part of the scroll compressor in Embodiment 2 of this invention. It is a cross-sectional enlarged view of the communicating hole part of the scroll compressor in Embodiment 3 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fixed scroll 2 Discharge hole 3 Rocking scroll 4 Oldham ring 5 Thrust bearing 6 Crankshaft 7 Oil hole 8 Main frame 9 Subframe 10 Balance weight 11 Stator 12 Rotor 13 Sealed container 14 Discharge muffler 15 Oil return pipe 16 Discharge pipe 17 Inhalation Pipe 18 Lubricating oil 19 Compression chamber 20 Discharge valve 21 Muffler chamber 22 Chamber 23 Low-pressure space 24 High-pressure space 25 Communication hole 26 Ball valve 27 Suction passage 28 Positive displacement pump 29 Bearings 30 and 30a Sealed container step 31 Valve seat

Claims (3)

An airtight container, a compression element that is disposed in the airtight container and includes a fixed scroll and an orbiting scroll, and a frame that is shrink-fitted and accommodated in the airtight container and accommodates the compression element. Compressed by scrolling so that the high-pressure space that discharges the high-pressure refrigerant gas compressed in step 1 and the low-pressure space in the suction pressure atmosphere are communicated with each other by the communication hole provided in the fixed scroll. In the machine
The fixed scroll has a discharge valve disposed on the side opposite to the swing scroll side so as to cover a part of the communication hole, and communicates and blocks between the compression space and the high pressure space. A chamber having a muffler chamber communicating with a compression space from a discharge port to the discharge valve;
A valve seat provided at a lower portion in the communication hole;
When the communication hole is closed, the communication hole is placed in close contact with the valve seat to close the communication hole, and when the communication hole is opened, the chamber is moved away from the valve seat to the high pressure space. A ball valve that is restrained from moving,
A scroll compressor characterized by comprising:   2. The scroll compressor according to claim 1, wherein a counterbore depth of the high-pressure space side opening of the communication hole is made smaller than a radius of the ball valve.   The scroll compressor according to claim 1, wherein an upper step portion and a lower step portion for suppressing displacement of the frame are provided above and below the frame shrink-fitting fixing portion in the hermetic container.

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