JP2021173264A - Compressor and air conditioner - Google Patents

Abstract

To provide a compressor which can prevent a bearing from being deformed by a differential pressure between an interior and an exterior of a compression chamber and fastening by a fastening member, and to provide an air conditioner.SOLUTION: A compressor includes: an electric motor; a rotary shaft which is driven by the electric motor and has an eccentric part; a rotating body which revolves by rotation of the eccentric part; a cylinder which rotatably houses the rotating body; a bearing which forms a compression chamber with the cylinder and rotatably supports the rotary shaft; and a discharge valve provided at a discharge port which discharges a fluid compressed in the compression chamber. The bearing has holes for fastening the bearing to the cylinder with fastening members. A distance from an inner wall surface of the cylinder to the hole located closest to the discharge valve is larger than distances from the inner wall surface of the cylinder to the other holes.SELECTED DRAWING: Figure 5

Description

The present invention relates to a compressor and an air conditioner including the compressor.

In the rotary compressor, the upper and lower bearings of the cylinder are fastened with bolts to form a compression chamber for compressing the refrigerant (see, for example, Patent Document 1). There are two chambers in the compression chamber: an eccentric part of the crank shaft that is rotatably supported by the upper bearing and the lower bearing, a roller that is rotatably arranged in the eccentric part, and a roller that comes into contact with the outer circumference of the roller. There is a vane that divides the suction chamber and the discharge chamber). In the rotary compressor, the eccentric part and the roller rotate around the central axis of the crank shaft to compress the refrigerant sucked from the hole provided in the inner diameter of the cylinder, and the rotary compressor is provided in the upper bearing, the lower bearing, or both. While pushing up the discharge valve, discharge from the discharge port to the outside of the compression chamber.

Japanese Unexamined Patent Publication No. 2005-030232

In the above-mentioned conventional compressor, a bolt hole for fixing the cylinder is provided at a position where the distance from the inner wall surface of the cylinder is substantially the same, and the bolt is passed through the bolt hole to fix the cylinder. In this structure, there is a problem that the discharge valve mounting portion of the bearing, which is thinner than other parts, is greatly deformed even if the bearing is fastened at the same position with the same torque.

Immediately after the compressed refrigerant is discharged from the discharge port, the suction pressure is in the compression chamber, which is lower than the discharge pressure outside the compression chamber. Then, there is also a problem that the discharge valve mounting portion is greatly deformed due to the differential pressure inside and outside the compression chamber.

In view of the above problems, the present invention
With an electric motor
A rotating shaft driven by an electric motor and having an eccentric part,
A rotating body that revolves by rotating the eccentric part,
A cylinder that rotatably accommodates the rotating body,
Bearings that form a compression chamber together with the cylinder and rotatably support the rotating shaft,
Includes a discharge valve provided at the discharge port that discharges the compressed fluid in the compression chamber.
Bearings have multiple holes in the cylinder for fastening with fastening members.
A compressor is provided in which the distance from the inner wall surface of the cylinder to the hole closest to the discharge valve is greater than the distance from the inner wall surface of the cylinder to the other holes.

According to the present invention, it is possible to suppress the deformation of the bearing due to the fastening of the fastening member and the differential pressure inside and outside the compression chamber.

The figure which showed the configuration example of the air conditioner. The figure which showed the configuration example of the outdoor unit. A cross-sectional view showing an example of the overall configuration of a compressor. The figure which showed the detailed structure of a compression mechanism. The figure explaining the position of the hole for fastening using a fastening member. The cross-sectional view cut along the cutting line AA. The figure which showed the 1st example of the position of the hole provided in a cylinder. The figure which showed the 2nd example of the position of the hole provided in a cylinder.

FIG. 1 is a diagram showing a configuration example of an air conditioner. The air conditioner includes an indoor unit 10 installed indoors of a house or the like and an outdoor unit 11 installed outdoors. The indoor unit 10 and the outdoor unit 11 are not limited to one unit each, and may be a plurality of units. In addition to the indoor unit 10, a remote controller 12 for operating the indoor unit 10 can be provided in the room.

The indoor unit 10 and the outdoor unit 11 are connected by pipes 13 and 14, and are configured so that the refrigerant circulates in the pipes 13 and 14. As the refrigerant, a mixture of difluoromethane and pentafluoroethane (R410A) or the like can be used.

The indoor unit 10 sucks in the indoor air, cools or warms the indoor air with a circulating refrigerant, and blows out the cooled or warmed air. By repeating this, the room is cooled or warmed. The outdoor unit 11 supplies the refrigerant to the indoor unit 10, heats or cools the refrigerant returned from the indoor unit 10, and supplies the refrigerant to the indoor unit 10 again.

FIG. 2 is a diagram showing a configuration example of the outdoor unit 11 constituting the air conditioner. The outdoor unit 11 includes a fan 20 that sucks in and blows out outside air, a heat exchanger 21 that heats or cools the sucked air, and a compressor 22 that circulates a refrigerant between the indoor unit 10 and the outdoor unit 11. .. Further, the outdoor unit 11 includes a control device 23 that communicates with the indoor unit 10 and controls the outdoor unit 11, an outdoor expansion valve 24, and a four-way valve 25 for switching the direction in which the refrigerant flows. Further, the outdoor unit 11 includes various sensors such as a temperature sensor for measuring the outside temperature, a sensor for measuring the current supplied to the compressor 22, a sensor for measuring the flow rate of the refrigerant, a sensor for measuring the pressure of the refrigerant, an accumulator, and the like. To be equipped with.

The outdoor unit 11 starts operation in response to an instruction from the indoor unit 10 to start operation. The control device 23 controls the outdoor unit 11 so as to operate in cooperation with the indoor unit 10. The control device 23 activates the compressor 22 and starts the circulation of the refrigerant with the indoor unit 10.

The control device 23 activates the fan 20. The heat exchanger 21 exchanges heat between the circulating refrigerant and the outside air taken in by the fan 20, and evaporates or condenses the refrigerant. The outdoor expansion valve 24 expands the refrigerant and controls the flow rate of the refrigerant. The four-way valve 25 switches the direction in which the refrigerant flows according to the set operation mode.

When the operation mode is the cooling mode, when the compressor 22 compresses and discharges the refrigerant, the high temperature and high pressure refrigerant is supplied to the heat exchanger 21. The refrigerant exchanges heat with the outside air sucked by the fan 20, is cooled, and condenses. The refrigerant is expanded by the outdoor expansion valve 24, the temperature is lowered, a part of the refrigerant is vaporized, and the refrigerant is sent from the outdoor unit 11 to the indoor unit 10 through the pipe 13 in a state of a two-phase flow of gas and liquid. At this time, the flow rate of the refrigerant circulating in the compressor 22 is adjusted by the outdoor expansion valve 24. The refrigerant exchanges heat with the indoor air in the indoor unit 10 and then returns to the compressor 22 through the pipe 14. This operation is repeated, and the room is cooled to the set temperature with the blown cold air.

When the operation mode is the heating mode, the four-way valve 25 switches the direction in which the refrigerant flows in the direction opposite to that in the case of cooling. When the compressor 22 adiabatically compresses the refrigerant and discharges it in a high temperature and high pressure state, it is sent to the indoor unit 10 through the pipe 14 instead of the heat exchanger 21. The refrigerant exchanges heat with the indoor air in the indoor unit 10 and then returns to the outdoor unit 11 through the pipe 13.

The outdoor unit 11 expands the high-pressure refrigerant condensed by the outdoor expansion valve 24. As a result, the refrigerant is in a low temperature and low pressure state. At this time, the flow rate of the refrigerant circulating in the compressor 22 is adjusted by the outdoor expansion valve 24. After that, it is supplied to the heat exchanger 21 and exchanged with the outside air sucked by the fan 20, and then returned to the compressor 22. This operation is repeated to warm the room to the set temperature with the warm air blown out.

FIG. 3 is a cross-sectional view showing an example of the overall configuration of the compressor. The compressor 22 is connected to the accumulator 26 and sucks the refrigerant through the accumulator 26. The accumulator 26 is a container for accumulating refrigerant gas.

The compressor 22 includes an electric motor and a compression mechanism in the closed container 30. The closed container 30 is composed of a hollow cylindrical case 30a, a lid chamber 30b that covers the upper part of the case 30a, and a bottom chamber 30c that covers the bottom of the case 30a. The lid chamber 30b is provided with a discharge pipe 31 for discharging the compressed refrigerant.

An accumulator 26 is fixed to the outer surface of the case 30a, and the refrigerant gas is sucked into the compressor 22 from the accumulator 26.

A rotor 32 and a stator 33 constituting an electric motor are provided in the closed container 30. The rotor 32 is arranged at the center position of the closed container 30 and is rotated by a rotating magnetic field. The stator 33 are arranged apart from each other so as to surround the rotor 32, and receive an AC voltage to generate a rotating magnetic field.

A shaft 34 is connected to the rotor 32 as a rotation shaft so as to extend toward the bottom chamber 30c, and the rotation of the rotor 32 causes the shaft 34 to rotate in a certain direction.

A compression mechanism is provided under the electric motor in the closed container 30, and cylinders constituting the compression chamber of the compression mechanism are arranged. In the example shown in FIG. 3, two compression chambers are provided, and two cylinders are arranged. The two cylinders are an upper cylinder 35 on the motor side and a lower cylinder 36 on the bottom chamber 30c side, and the refrigerant gas is sucked into the inside from the accumulator 26. Therefore, the upper cylinder 35 and the lower cylinder 36 are provided with a suction port for sucking the refrigerant gas.

Refrigerating machine oil is stored in the bottom chamber 30c as a lubricating material for reducing wear of the sliding portion of the compression mechanism and maintaining sealing performance. The refrigerating machine oil is taken into the shaft 34 by the rotation of the shaft 34 and supplied to the sliding portion.

The configuration of the compression mechanism will be described in detail with reference to FIG. FIG. 4A shows a perspective view of the compression mechanism after assembly, and FIG. 4B shows a perspective view when the compression mechanism is disassembled into each component.

The upper cylinder 35 and the lower cylinder 36 have a cylindrical cavity, and a partition plate 37 is provided between the upper cylinder 35 and the lower cylinder 36, and the lower side of the upper cylinder 35 and the upper side of the lower cylinder 36 are provided. Close.

The shaft 34 is provided with an eccentric portion 38 at a position where the center of gravity is deviated from the center of the cross section of the shaft 34, and a ring-shaped rotating body (roller) 39 is arranged around the eccentric portion. The eccentric portion 38 and the roller 39 are housed in the respective cylindrical cavities of the upper cylinder 35 and the lower cylinder 36. The upper side of the upper cylinder 35 is closed by the upper bearing (upper bare) 40, and the upper bare 40, the upper cylinder 35, and the partition plate 37 form a compression chamber. The lower side of the lower cylinder 36 is closed by the lower bearing (lower bare) 41, and the lower bare 41, the lower cylinder 36, and the partition plate 37 form a compression chamber.

The upper cylinder 35 and the lower cylinder 36 have a storage groove 43 that abuts on the outer peripheral surface of the roller 39 housed inside and houses a vane 42 that divides the compression chamber into two. The vane 42 maintains a state in which the rear side having a plurality of notches is urged by a spring or the like and the front side is pressed against the outer peripheral surface of the roller 39, and the compression chamber is divided into a suction side chamber and a discharge side chamber. Keep separated into two rooms.

The upper bare 40 and the lower bare 41 rotatably support the upper cylinder 35, the partition plate 37, and the lower cylinder 36 on the shaft 34. The upper bare 40 and the lower bare 41 are fastened to the upper cylinder 35 and the lower cylinder 36 by using a fastening member such as a bolt. Therefore, the upper cylinder 35, the lower cylinder 36, the partition plate 37, the upper bare 40, and the lower bare 41 are provided with bolt holes 44 for passing bolts.

With reference to FIG. 3 again, each roller 39 revolves by the rotation of each eccentric portion 38, and compresses the refrigerant gas sucked into the upper cylinder 35 and the lower cylinder 36. The compressed refrigerant gas is discharged from the discharge ports provided in the upper cylinder 35 and the lower cylinder 36 to the primary space 45 formed between the upper cylinder 35 and the electric motor via the discharge valve.

The refrigerant gas discharged to the primary space 45 is sent to the secondary space 46 on the upper side of the motor through the gap between the rotor 32 and the stator 33, the gap between the stator 33 and the case 30a, and the like, and is sent to the secondary space 46 on the upper side of the motor and the lid. It is discharged from the discharge pipe 31 provided in the chamber 30b.

The compression mechanism may include an upper cup 47 and a lower cup 48 that function as silencers in order to suppress noise when the high-pressure refrigerant gas is discharged.

5 and 6 are views for explaining the positions of bolt holes for fastening using bolts as fastening members. The upper bare 40 and the lower bare 41 are fastened to the upper cylinder 35 and the lower cylinder 36 using bolts 49. Here, only an example in which the upper bear 40 is fastened to the upper cylinder 35 will be described, but the same applies to the case where the lower bare 41 is fastened to the lower cylinder 36.

FIG. 5 is a view showing a place where the upper bare 40 is fastened to the upper cylinder 35 by using a bolt 49, and FIG. 6 is a cross-sectional view taken along the cutting line AA of FIG. The upper bare 40 is provided with a mounting portion 51 for mounting the discharge valve 50.

Referring to FIG. 6, the upper bare 40 is arranged adjacent to the upper cylinder 35 and fastened by bolts 49. The upper bare 40 has a mounting portion 51 in a recess, and the bolt 49 is fastened so that the head of the bolt 49 comes into contact with a surface one step higher than the recess. A discharge port 52 is provided in the mounting portion 51, and a cylinder notch (discharge guide) 53 is provided in a portion of the upper cylinder 35 that continues to the discharge port 52.

A discharge valve 50 is installed in the mounting portion 51 so as to close the discharge port 52. The discharge valve 50 is held in a closed state by a discharge valve restraint called a retainer 54. One end of the retainer 54 is fixed by a fixing member such as a rivet 55, and the other end is curved so that the retainer 54 can move upward.

The refrigerant gas compressed in the upper cylinder 35 is guided to the discharge port 52 through the discharge guide 53 and pushes up the discharge valve 50. The discharge port 52 is opened by pushing up the discharge valve 50, and the refrigerant gas is discharged to the outside from the opened discharge port 52.

The refrigerant gas discharged through the discharge valve 50 is discharged into the space covered by the upper cup 47 shown in FIG. The upper cup 47 is provided with a hole, and the upper cup 47 is guided to the primary space 45 through the hole.

When the upper bare 40 is fastened to the upper cylinder 35 with bolts 49, bolt holes are provided at the same radial distance around the shaft 34, and the bolts 49 are screwed into the bolt holes for fastening. Then, the position of the bolt 49 closest to the discharge valve 50 becomes a position close to the recess of the mounting portion 51.

As shown in FIG. 6, the recess of the mounting portion 51 is thinner than the thickness of the portion other than the recess of the upper bare 40. In the example shown in FIG. 6, the thickness of the recess is approximately 1/3 of the thickness of the other portion. If the bolt 49 is used to fasten the portion close to such a thin portion with the same torque as other portions, the upper cylinder 35 may be deformed inward.

Further, after the high-pressure refrigerant gas is discharged through the discharge valve 50, the suction pressure is lowered, so that a large differential pressure is generated inside and outside the compression chamber, and the differential pressure may cause deformation to the inside of the upper cylinder 35. When deformation occurs due to bolt fastening, the strength of the recess is reduced, and this differential pressure may further increase the deformation.

Therefore, the distance in the radial direction from the inner wall surface of the cylindrical cavity of the upper cylinder 35 of the bolt hole closest to the mounting portion 51 of the discharge valve 50 is made larger than the distance of the other bolt holes. Then, as shown in FIG. 5, the bolt 49a closest to the mounting portion 51 is located at a position separated from the position of the other bolt 49 at a certain distance centered on the shaft 34 indicated by the alternate long and short dash line, and the bolt is fastened. Deformation can be suppressed, and deformation due to differential pressure inside and outside the compression chamber can also be suppressed. As a result, the sum of the amount of deformation due to the fastening of the bolt 49a and the amount of deformation due to the differential pressure inside and outside the compression chamber is the sum of the amount of deformation due to the fastening of other bolts and the amount of deformation due to the differential pressure inside and outside the compression chamber). Can be equivalent to.

If all the bolt holes are separated from the inner wall surface of the upper cylinder 35 in the radial direction, the force for bringing the end face of the upper bare 40 into close contact with the end face of the upper cylinder 35 becomes weaker, and a gap is generated. In this case, the compressed refrigerant gas leaks from the generated gap. Therefore, it is effective to keep only the bolt 49a closest to the mounting portion 51, which is greatly affected by deformation.

FIG. 7 is a diagram showing a first example of the position of the bolt hole provided in the upper cylinder 35. Since the lower cylinder 36 is the same as the upper cylinder 35, description thereof will be omitted here. The upper cylinder 35 has a cylindrical cavity 56 in which the eccentric portion 38 and the roller 39 are accommodated, and has an accommodating groove 43 that extends continuously in one direction in the cavity 56 and in which the vane 42 slides. Refrigerating machine oil is supplied to sliding portions such as between the shaft 34 and the upper bare 40 and the lower bare 41, between the vane 42 and the accommodating groove 43, and between the upper cylinder 35 and the roller 39.

Since the upper cylinder 35 internally compresses the refrigerant, bolt holes 58a to 58c are provided on a one-point chain line having a constant wall thickness and a constant distance in the radial direction from the inner wall surface 57 facing the cavity 56. .. The upper cylinder 35 is also provided with a discharge guide 53, a rivet hole 59, and the like. The mounting portion 51 is located at the position indicated by the broken line, and the bolt hole 58d closest to the mounting portion 51 is above the alternate long and short dash line on the outer wall surface side of the cylinder 35, that is, the distance from the inner wall surface is farther than the other bolt holes 58a to 58c. It is provided at the position.

Assuming that the distances from the inner wall surface 57 of the cavity 56 to the centers of the bolt holes 58a to 58d are L1 to L4, L4> L1≈L2≈L3. The intervals between the bolt holes 58a to 58c are substantially constant. In this example, the number of bolt holes 58a to 58d is four, but the present invention is not limited to this, and the number of bolt holes 58a to 58d may be three or five or more.

FIG. 8 is a diagram showing a second example of the position of the bolt hole provided in the upper cylinder 35. Similar to the example shown in FIG. 7, the example shown in FIG. 8 is also provided with four bolt holes 58a to 58d. In the example shown in FIG. 7, the four bolt holes 58a to 58d are provided in different directions by approximately 90 °, but the end surface of the upper cylinder 35 is formed by moving the bolt holes 58d away from the inner wall surface 57 of the upper cylinder 35. Since the adhesion between the upper bare 40 and the end face of the upper bare 40 is reduced, a gap is likely to occur between the end face of the upper cylinder 35 and the end face of the upper bare 40.

Therefore, in order to reduce the gap generated between the end surface of the upper cylinder 35 and the end surface of the upper bare 40, the bolt holes 58a and 58c adjacent to the separated bolt holes 58d can be brought closer to the bolt holes 58d. If the angles formed by the line segments connecting the center of the cavity 56 and the centers of the bolt holes 58a to 58d are θa, θb, θa', and θb', respectively, then θa <θa'and θb <θb'.

As described above, by suppressing the deformation due to the bolt fastening and the differential pressure inside and outside the compression chamber, the movement of the roller 39 and the vane 42 is prevented from being hindered, and the reliability and performance of the compressor 22 are improved. be able to. Although the rotary compressor has been described as an example of the compressor 22, the compressor 22 is not limited to the rotary compressor. Therefore, the compressor 22 may be a scroll compressor or the like. Further, the cylinder may be one cylinder, or the upper portion of one cylinder may be covered with an upper cylinder 35 and the lower portion may be covered with a lower cylinder 36 to form one compression chamber.

Although the compressor and the air conditioner of the present invention have been described in detail with the above-described embodiments, the present invention is not limited to the above-described embodiments, and other embodiments, additions, modifications, and the like. It can be changed within the range that can be conceived by those skilled in the art, such as deletion, and is included in the scope of the present invention as long as the action and effect of the present invention are exhibited in any of the embodiments.

10 ... Indoor unit 11 ... Outdoor unit 12 ... Remote controller 13, 14 ... Piping 20 ... Fan 21 ... Heat exchanger 22 ... Compressor 23 ... Control device 24 ... Outdoor expansion valve 25 ... Four-way valve 26 ... Accumulator 30 ... Sealed container 30a ... Case 30b ... Lid chamber 30c ... Bottom chamber 31 ... Discharge pipe 32 ... Rotor 33 ... Stator 34 ... Shaft 35 ... Upper cylinder 36 ... Lower cylinder 37 ... Partition plate 38 ... Eccentric part 39 ... Roller 40 ... Upper bare 41 ... Lower bear 42 ... Vane 43 ... Accommodating groove 44 ... Bolt hole 45 ... Primary space 46 ... Secondary space 47 ... Upper cup 48 ... Lower cup 49, 49a ... Bolt 50 ... Discharge valve 51 ... Mounting part 52 ... Discharge port 53 ... Discharge Guide 54 ... Retainer 55 ... Rivet 56 ... Cavity 57 ... Inner wall surface 58a-58d ... Bolt hole 59 ... Rivet hole

Claims (7)

With an electric motor
A rotating shaft driven by the motor and having an eccentric portion,
A rotating body that revolves by the rotation of the eccentric part and
A cylinder that rotatably accommodates the rotating body and
A bearing that forms a compression chamber together with the cylinder and rotatably supports the rotating shaft.
Including a discharge valve provided at a discharge port for discharging the compressed fluid in the compression chamber.
The bearing has a plurality of holes for fastening to the cylinder using a fastening member.
A compressor in which the distance from the inner wall surface of the cylinder to the hole closest to the discharge valve is larger than the distance from the inner wall surface of the cylinder to other holes. The compressor according to claim 1, wherein the other holes other than the hole closest to the discharge valve are located at a predetermined distance from the inner wall surface of the cylinder and are provided at regular intervals. The other holes except the hole closest to the discharge valve are at a predetermined distance from the inner wall surface of the cylinder, and two holes adjacent to the hole closest to the discharge valve are maintained at the predetermined distance. The compressor according to claim 1, wherein the hole is brought closer to the hole closest to the discharge valve. The discharge valve is attached to a recess provided in the bearing, and the thickness of the recess is thinner than the thickness of a portion other than the recess of the bearing, according to any one of claims 1 to 3. Compressor. The bearing includes an upper bearing that covers the upper part of the cylinder and a lower bearing that covers the lower part of the cylinder.
The compressor according to any one of claims 1 to 4, wherein the discharge valve is provided on the upper bearing or the lower bearing. Including two or more of the cylinders
Further including one or more partition members for partitioning between two or more cylinders,
The compression according to any one of claims 1 to 5, wherein the bearing includes an upper bearing covering the uppermost portion of the two or more cylinders and a lower bearing covering the lowermost portion of the two or more cylinders. Machine. An air conditioner comprising one or more indoor units and an outdoor unit including the compressor according to any one of claims 1 to 6.

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