WO2017158809A1

WO2017158809A1 - Compressor

Info

Publication number: WO2017158809A1
Application number: PCT/JP2016/058656
Authority: WO
Inventors: 雷人河村; 関屋　慎; 渉岩竹; 佐々木　圭
Original assignee: 三菱電機株式会社
Priority date: 2016-03-18
Filing date: 2016-03-18
Publication date: 2017-09-21
Also published as: JPWO2017158809A1

Abstract

This compressor is provided with: a sealed container having an oil reservoir space for collecting oil in the bottom; a compression mechanism part accommodated in the sealed container, the compression mechanism part compressing a fluid that flows into the sealed container; an electric motor accommodated in the sealed container, the electric motor generating rotational force; a rotating shaft which transmits the rotational force generated by the electric motor to the compression mechanism part, the inside of the rotating shaft being formed an oil supply path extending in an axial direction from an end part; an oil supply pump provided to the end-part side of the rotating shaft, the oil supply pump being actuated by the rotation of the rotating shaft, drawing out the oil in the oil reservoir space to supply the oil to the oil supply path, and having an oil flow path through which the oil flows and an oil outlet provided to the oil flow path; and a valve mechanism provided to the oil outlet. The valve mechanism has: a housing having a hollow part leading to the oil outlet, the housing having a discharge port leading to the oil reservoir space formed therein; and a valve body accommodated in the housing and moved by the pressure of the oil in the oil outlet. When the rotational speed of the rotating shaft is equal to or greater than a prescribed speed, the oil outlet is opened by the movement of the valve body, the oil is discharged from the discharge port to the oil reservoir space, and the discharge port of the valve mechanism is positioned inside the oil reservoir space.

Description

Compressor

The present invention relates to a compressor having an oil pump attached to a rotating shaft.

Conventionally, a sealed container in which oil is stored at the bottom, a rotary shaft having an oil supply passage inside, a compression mechanism that compresses fluid by rotation of the rotary shaft, and a lower end of the rotary shaft are provided at the bottom of the oil reservoir. There is known a compressor that includes an oil supply pump that supplies an oil supply path to a compression mechanism unit. In this compressor, various methods are used in order to suppress excessive oil supply to the compression mechanism (see, for example, Patent Document 1). Patent Document 1 discloses a compressor in which a valve path communicating with an oil supply path and extending in a radial direction is formed at a position above the oil supply pump of the rotating shaft, and a valve body is provided at the outlet of the valve path. ing.

International Publication No. 2015/104863

However, in the compressor of Patent Document 1, since the valve path is located above the oil supply pump, the oil discharged from the valve path is scattered into the refrigerant gas space inside the sealed container. Then, mist-like oil floats in the refrigerant gas space, and the refrigerant gas and the oil flow into the compression mechanism together. As a result, the amount of oil that flows out of the compressor increases, the oil in the compressor is depleted, and the reliability decreases.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a highly reliable compressor with a small amount of oil rising.

The compressor of the present invention includes a sealed container having an oil sump space for storing oil at the bottom, a compression mechanism unit that compresses the fluid that flows into the sealed container and is stored in the sealed container, and is stored in the sealed container and rotates. An electric motor that generates a force, and a rotational force generated by the electric motor are transmitted to the compression mechanism unit, and a rotation shaft that is provided with an oil supply passage that extends in the axial direction from the end portion is provided on the end portion side of the rotation shaft. An oil supply pump that operates by rotating the shaft, sucks oil in the oil sump space, and supplies it to the oil supply passage, and has an oil passage through which oil flows and an oil outlet provided in the oil passage; The valve mechanism is provided with a housing having a hollow portion communicating with the oil outlet and having a discharge port leading to the oil sump space, and the pressure of the oil at the oil outlet accommodated in the housing. And a valve body that is moved by rotation of the rotating shaft The oil outlet is opened by the movement of the valve body when the pressure exceeds the specified value, and the oil is discharged from the discharge port to the oil sump space. The discharge port of the valve mechanism is located in the oil sump space. It is.

According to the compressor of the present invention, oil is returned from the valve mechanism to the inside of the oil sump space, so that mist-like oil can be prevented from being mixed into the refrigerant gas space when returning oil. Therefore, it is possible to improve reliability with a small amount of oil rising while reducing power loss due to oil agitation.

It is a longitudinal cross-sectional schematic diagram which shows the compressor which concerns on Embodiment 1 of this invention. It is a schematic diagram which shows an example of the oil supply pump in the compressor of FIG. It is a schematic diagram which shows an example of the oil supply pump in the compressor of FIG. It is a schematic diagram which shows the operation example of the valve mechanism in the compressor of FIG. It is a schematic diagram which shows the operation example of the valve mechanism in the compressor of FIG. 6 is a graph showing the relationship between the rotational speed of a compressor using the valve mechanism of FIGS. 2 to 5 and the amount of oil supplied by an oil supply pump. It is a schematic diagram which shows an example of the conventional valve mechanism. It is a schematic diagram which shows an example of the valve mechanism of the compressor which concerns on Embodiment 2 of this invention. It is a schematic diagram which shows an example of the valve mechanism of the compressor which concerns on Embodiment 2 of this invention. It is a schematic diagram which shows an example of the valve mechanism of the compressor which concerns on Embodiment 2 of this invention. 11 is a graph showing the relationship between the number of revolutions and the amount of oil supply in the valve mechanism of FIGS. It is a schematic diagram which shows the shape of the discharge port of the valve mechanism of the compressor which concerns on Embodiment 3 of this invention. It is a schematic diagram which shows the shape of the discharge port of the valve mechanism of the compressor which concerns on Embodiment 3 of this invention. It is a schematic diagram which shows the shape of the discharge port of the valve mechanism of the compressor which concerns on Embodiment 3 of this invention. It is a schematic diagram which shows an example of the valve mechanism of the compressor which concerns on Embodiment 4 of this invention. It is a schematic diagram which shows an example of the valve mechanism of the compressor which concerns on Embodiment 4 of this invention. It is a graph which shows the relationship between the rotation speed of the compressor using the valve mechanism of FIG.15 and FIG.16, and the amount of oil supply by an oil supply pump. It is a schematic diagram which shows an example of the oil supply pump in the compressor which concerns on Embodiment 5 of this invention. It is a longitudinal cross-sectional view which shows an example of the compressor which concerns on Embodiment 6 of this invention.

Embodiment 1 FIG.
Hereinafter, embodiments of a compressor of the present invention will be described with reference to the drawings. FIG. 1 is a schematic longitudinal sectional view showing a compressor according to Embodiment 1 of the present invention. A compressor 1 in FIG. 1 is a so-called vertical scroll compressor, and compresses and discharges a working gas such as a refrigerant. The compressor 1 includes a sealed container 2, a rotating shaft 7, an electric motor 8, a compression mechanism unit 10, and an oil supply pump 20.

The sealed container 2 is formed in a cylindrical shape, for example, and has pressure resistance. A suction pipe 2 a for taking the working gas into the sealed container 2 is connected to the side surface of the sealed container 2, and a discharge pipe 2 b for discharging the compressed working gas from the sealed container 2 is connected to the upper surface. Further, an oil sump space 2c for storing refrigeration oil is formed at the bottom of the sealed container 2. And the rotating shaft 7, the electric motor 8, the compression mechanism part 10, and the oil supply pump 20 are accommodated in the airtight container 2. FIG.

In the sealed container 2, the frame 3 is fixed to the upper part of the electric motor 8, and the sub-frame 4 that holds the rotating shaft 7 is fixed to the lower part of the electric motor 8. The frame 3 is provided with a flow path 3 a for supplying the working gas flowing in from the suction pipe 2 a to the compression mechanism unit 10. An insertion hole for inserting the rotary shaft 7 is formed in the frame 3, and a main bearing 5 made of a sliding bearing such as a copper-lead alloy is fixed to the insertion hole by press-fitting or the like. On the other hand, the sub frame 4 is provided with a sub bearing 6 made of, for example, a ball bearing. The main bearing 5 and the sub bearing 6 pivotally support the rotating shaft 7. In addition, although illustrated about the case where the main bearing 5 consists of a sliding bearing and the subbearing 6 consists of a ball bearing, you may support by another well-known bearing structure. The oil sump space 2 c is a space below the subframe 4 that supports the end of the rotating shaft 7, below the sub-bearing 6, below the end of the rotating shaft 7, and the like. In the vertical arrangement in which the rotary shaft 7 is in the vertical direction, the oil is often contained in the oil sump space 2c. However, the oil is not always stored in the oil sump space 2c, and the upper surface of the oil is higher than the sump space 2c depending on the amount of oil put in the compressor, the operating conditions of the refrigerant system using the compressor, and the like. That is, it may be above the subframe 4 or the sub-bearing 6.

Inside the rotary shaft 7, an oil supply passage 7x extending in the axial direction (arrow Z direction) from the end of the rotary shaft 7 and a plurality of supply passages 7y extending in the radial direction leading to the oil supply passage 7x are formed. . Oil is supplied to the sliding parts such as the main bearing 5 and the auxiliary bearing 6 through the oil supply path 7x and the supply path 7y. An oil supply passage 7x is opened at the axial end of the rotary shaft 7, and oil pressurized by the oil supply pump 20 is supplied from this opening. An eccentric shaft portion 7 a is attached to one end side of the rotating shaft 7 in an eccentric state with respect to the rotating shaft 7, and the eccentric shaft portion 7 a is connected to the compression mechanism portion 10. Note that a first balance weight 9 a is fixed to the rotating shaft 7 in order to balance the entire rotating system in the compressor 1.

The electric motor 8 rotates the rotary shaft 7, and has an electric motor rotor 8a and an electric motor stator 8b to generate a rotational force. The rotating shaft 7 transmits the rotational force generated by the electric motor 8 to the compression mechanism unit 10. The electric motor rotor 8a is fixed to the rotary shaft 7 by shrink fitting or the like, and the electric motor stator 8b is fixed to the sealed container 2 by shrink fitting or the like. The motor stator 8b is connected to a glass terminal (not shown) that exists between the motor stator 8b and the glass terminal, and the glass terminal is connected to a lead wire for obtaining electric power from the outside. When electric power is supplied to the motor stator 8b, the rotating shaft 7 and the motor rotor 8a rotate with respect to the motor stator 8b. A second balance weight 9b is fixed to the motor rotor 8a.

The compression mechanism unit 10 compresses a fluid (for example, a refrigerant) sucked into the sealed container 2 from the suction pipe 2a, and includes a rocking scroll 11 and a fixed scroll 12. The swing scroll 11 is supported by the frame 3 so as to be capable of revolving, and a cylindrical swing bearing 11 a is provided on the lower surface of the swing scroll 11. The eccentric shaft portion 7a of the rotary shaft 7 is inserted into the rocking bearing 11a, and the rocking scroll 11 performs a revolving motion by the rotation of the eccentric shaft portion 7a. An Oldham ring (not shown) is supported between the frame 3 and the orbiting scroll 11 so as to be swingable on the frame 3 in order to give a swinging motion while preventing the swinging scroll 11 from rotating. Is provided. Further, a slider 9 is provided between the rotary shaft 7 and the swing scroll 11, and the swing radius of the slider 9 is increased by the force due to the pressure of the working gas and the centrifugal force acting on the swing scroll 11. A variable crank mechanism is configured that moves in the direction and converts the rotation of the rotary shaft 7 into a revolving motion.

The fixed scroll 12 is arranged on the top of the swing scroll 11 and is fixed to the frame 3. A discharge port 12a for discharging the working gas is formed at the center of the fixed scroll 12, and a baffle 13 and a discharge valve 14 for preventing a back flow of the compressed working gas are disposed on the discharge port 12a. . Further, a discharge muffler container 15 is provided above the discharge valve 14. Then, the working gas compressed in the compression mechanism unit 10 is discharged from the discharge pipe 2b through the discharge port 12a, the baffle 13 and the discharge muffler container 15.

The orbiting scroll 11 has a spiral body 11b, the fixed scroll 12 has a spiral body 12b, and the orbiting scroll 11 and the fixed scroll 12 are arranged so that the

spiral bodies

11b and 12b face each other. The spiral body 11 b and the spiral body 12 b are combined in opposite phases, and a compression chamber is formed between the spiral portion of the fixed scroll 12 and the spiral portion of the orbiting scroll 11.

The oil supply pump 20 is attached to the other end side of the rotary shaft 7, and oil stored in the oil sump space 2 c of the hermetic container 2 in the oil supply path 7 x in the rotary shaft 7 is supplied to the main bearing 5, the sub-bearing 6, and the rocker. It is supplied to each sliding part such as the dynamic bearing 11a. The oil supply pump 20 is composed of a rotary positive displacement pump, for example, and the oil supply pump 20 is operated by the rotation of the rotary shaft 7. The oil supply pump 20 has a characteristic that the amount of oil supplied to the oil supply passage 7x increases as the rotational speed of the rotary shaft 7 increases.

2 and 3 are schematic views showing an example of an oil supply pump in the compressor of FIG. 1, and the oil supply pump 20 will be described with reference to FIGS. The oil supply pump 20 is a so-called trochoid pump, and includes a holder 21, an outer rotor 22, an inner rotor 23, and an inflow pipe 24. The holder 21 is housed in the subframe 4 and supports the rotary shaft 7 in the axial direction on the upper end surface. The outer rotor 22 has an outer peripheral surface formed in a circular cross section, and is rotatably accommodated in the holder 21. The outer rotor 22 is housed in the holder 21 in an eccentric state with respect to the rotating shaft 7. A plurality of teeth formed with a trochoid curve are formed on the inner peripheral surface of the outer rotor 22.

The inner rotor 23 is accommodated in the outer rotor 22 and is fixed to the rotary shaft 7. A plurality of teeth formed in a tocoloid curve are formed on the outer peripheral surface of the inner rotor 23, and the number of teeth of the inner rotor 23 is, for example, one less than the number of teeth of the outer rotor 22. The volume of the gap defined by the inner rotor 23 and the outer rotor 22 is enlarged / reduced in accordance with these rotations. The rotary pump mechanism such as the inner rotor 23 and the outer rotor 22 is provided with a suction port and a discharge port so that oil is sucked in at a rotation angle position where the gap is enlarged and discharged at a reduction angle position. (Part surrounded by a dotted line in FIG. 3). The suction port is connected to the inflow pipe 24. When the gap is reduced, pressure is applied to the oil, so that the oil is pressurized and discharged. An oil inflow passage 21 a is formed between the bottom of the holder 21 and the outer rotor 22 and the inner rotor 23. The oil inflow path 21 a is a flow path that connects a space formed between the outer rotor 22 and the inner rotor 23 and the oil supply path 7 x of the rotating shaft 7. That is, the oil inflow path 21a is a flow path in the oil supply pump 20 until oil pressurized from the discharge port of the pump mechanism flows into the internal oil supply path 7x. An oil outlet 21 x formed of a through hole through which a part of the oil flowing through the oil inflow passage 21 a flows out to the outside of the holder 21 is provided at the bottom of the holder 21. In addition, although illustrated about the case where the oil outlet 21x is provided in the bottom part of the holder 21, as long as it leads to the oil inflow path 21a, a formation position is not ask | required. Moreover, although the trochoid type gear pump excellent in quietness and durability was shown as a pump mechanism of the oil supply pump 20, another pump mechanism using the rotation of the rotating shaft 7 may be used.

The inflow pipe 24 flows oil stored in the oil sump space 2c into the holder 21 and has, for example, a shape extending in the axial direction to the lower part of the oil sump space 2c. Thereby, even if it is an operating condition where oil decreases to the lower part of the oil sump space 2c, the oil can be immediately led to the inflow pipe 24, and an insufficient supply of oil can be prevented.

When the rotating shaft 7 rotates, the inner rotor 23 rotates, and the teeth of the inner rotor 23 and the teeth of the outer rotor 22 mesh with each other, whereby the outer rotor 22 rotates. At this time, the space between the outer rotor 22 and the inner rotor 23 is expanded and contracted in volume according to the rotational position due to the difference in the number of teeth. Thereby, the oil in the oil sump space 2 c at the bottom of the sealed container 2 is sucked up from the inflow pipe 24 into the holder 21. The oil in the holder 21 is supplied to the oil supply passage 7x of the rotary shaft 7 through the oil inflow passage 21a.

An example of the operation of the compressor 1 will be described with reference to FIGS. First, the working gas flows from the suction pipe 2 a into the lower space of the frame 3 in the sealed container 2, and flows into the middle space of the frame 3 through the two flow paths 3 a installed in the frame 3. On the other hand, the rotating shaft 7 rotates when electric power is supplied from the inverter device to the electric motor 8. The eccentric shaft portion 7a is rotated by the rotation of the rotating shaft 7, and the swing scroll 11 performs swing motion (revolution motion). At this time, the working gas is sucked into the compression chamber (not shown) in the compression chamber formed between the orbiting scroll 11 and the fixed scroll 12. The working gas is pressurized from a low pressure to a high pressure by the geometric volume change of the compression chamber accompanying the operation of both spiral bodies formed by the

spiral bodies

11 b and 12 b, and the high pressure refrigerant is discharged from the discharge pipe 2 b of the fixed scroll 12. Is discharged to the outside of the sealed container 2.

The oil flow during the operation of the compressor 1 will be described with reference to FIGS. First, with the rotation of the rotating shaft 7, the oil supply pump 20 is operated, and oil is supplied to the oil supply passage 7 x of the rotating shaft 7. This oil is supplied from the oil supply passage 7x and the supply passage 7y to the main bearing 5, the auxiliary bearing 6, the rocking bearing 11a, and the compression mechanism portion 10, respectively. The oil supplied to the auxiliary bearing 6 lubricates the auxiliary bearing 6 and then returns to the oil sump space 2 c below the sealed container 2. Further, the oil that has flowed into the compression mechanism 10 and the oil after the rocking bearing 11 a has been lubricated flows into the space formed by the rocking scroll 11 and the frame 3 (the space in the frame 3). Oil is returned to the lower oil sump space 2c. The remaining part of the oil passes between the thrust surface of the orbiting scroll 11 and the frame 3, is taken into the compression chamber, and is then discharged to the outside of the compressor 1.

As described above, when the oil supply pump 20 is a positive displacement pump, the amount of oil supplied to the oil supply passage 7x increases as the rotational speed of the rotary shaft 7 increases. Then, when the compressor 1 rotates at a high speed, the amount of oil supply becomes excessive, and as the amount of oil discharged to the outside of the compressor 1 (the amount of oil rising) increases, the refrigerating capacity and performance may decrease. Further, the space in which the rocking bearing 11a is stored is filled with oil, and power loss occurs due to the rocking bearing stirring the oil. Therefore, the compressor 1 is provided with a valve mechanism 30 that bypasses and discharges the oil supplied to the oil supply passage 7x directly into the oil sump space 2c in accordance with the rotational speed.

The valve mechanism 30 in FIG. 2 opens and closes the oil outlet 21x in accordance with the oil pressure applied from the oil supply pump 20, and returns the oil in the oil inflow passage 21a to the oil sump space 2c. A housing 31, a valve body 32, and an elastic member 33 are included. The valve mechanism 30 is a mechanism that opens and closes the mouth with the valve body 32, and may be rephrased as the valve mechanism 30. The housing 31 is disposed so as to cover the oil outlet 21x of the oil supply pump 20, and has a hollow portion 31a that communicates with the oil outlet 21x. The hollow portion 31a is formed to extend in the axial direction (arrow Z direction), for example.

A discharge port 31x communicating with the oil sump space 2c is formed on the side wall of the housing 31, and the discharge port 31x is located inside the oil sump space 2c. In FIG. 1, the entire oil pump 20 and valve mechanism 30 are located in the oil sump space 2c, and as a result, the discharge port 31x is also located in the oil sump space 2c. Here, the height of the oil level in the oil sump space 2c varies depending on the operating conditions. For this reason, it is preferable to install the discharge port 31x as low as possible. Thereby, the oil discharged from the discharge port 31x is returned to the inside of the oil sump space 2c even under the operating condition where the oil level is lowered.

The valve body 32 is moved by the oil pressure at the oil outlet 21x. It should be noted that the amount of movement of the valve body 32 only needs to change according to the magnitude of the oil pressure at the oil outlet 21x. Good. The valve body 32 is accommodated in the hollow portion 31a of the housing 31 so as to be movable in the axial direction (direction of arrow Z), and opens and closes the oil outlet 21x provided in the housing 31. The valve body 32 has, for example, approximately the same size as the cross-sectional area of the hollow portion 31 a of the housing 31, and restricts oil from flowing between the inner wall of the housing 31 and the valve body 32. The elastic member 33 is provided between the housing 31 and the valve body 32, and biases the valve body 32 toward the oil outlet 21x.

4 and 5 are schematic views showing an operation example of the valve mechanism in the compressor of FIG. FIG. 4 shows a state in low speed operation, and FIG. 5 shows a state in high speed operation. As shown in FIG. 4, when the valve body 32 is located between the oil outlet 21x and the discharge port 31x, the valve body 32 regulates the flow of oil from the oil outlet 21x to the discharge port 31x, and the oil outlet 21x is in a closed state. On the other hand, as shown in FIG. 5, when the valve body 32 is positioned between the discharge port 31x and the elastic member 33, the oil outlet 21x is opened, and the oil flows from the oil outlet 21x to the discharge port 31x. . The position of the valve body 32 in FIGS. 4 and 5 is determined by the pump pressure in the oil supply pump 20. That is, the position of the valve body 32 is determined according to the relationship between the pressure of the oil flowing into the housing 31 from the oil outlet 21x and the urging force of the elastic member 33, and the pressure of the oil is determined according to the rotation of the rotary shaft 7. Determined.

When the compressor 1 is operating at a low speed, the pumping amount of the positive displacement oil pump 20 is small, and the pump pressure generated in the oil inflow passage 21a is small. For this reason, as shown in FIG. 4, the urging force of the elastic member 33 becomes larger than the pump pressure, and the oil outlet 21 x is closed by the valve body 32.

On the other hand, when the compressor 1 is operating at high speed, the oil pumping amount of the positive displacement oil pump 20 is large, and the pump pressure generated in the oil inflow passage 21a increases. Therefore, as shown in FIG. 5, the pump pressure becomes larger than the urging force of the elastic member 33, the valve body 32 moves in the axial direction toward the elastic member 33, and the discharge port 31x is opened. Then, a part of the oil in the oil inflow path 21a is returned to the inside of the oil sump space 2c through the oil outlet 21x and the outlet 31x.

FIG. 6 is a graph showing the relationship between the rotational speed of the compressor using the valve mechanism of FIGS. 2 to 5 and the amount of oil supplied by the oil pump. In FIG. 6, when the oil supply pump 20 is a positive displacement pump, the rotational speed and the amount of oil supplied by the oil pump 20 are substantially proportional to each other, and the amount of oil increases as the rotational speed increases. As described above, when the valve mechanism 30 is provided in the oil supply pump 20, the discharge port 31x is opened during high speed operation when the rotation speed threshold value N1 is exceeded (see FIG. 5), which increases the rotation speed. Accordingly, the amount of oil supply will be reduced. Further, the discharge port 31x is closed during low-speed operation that is less than the rotation speed threshold N1. The rotation speed threshold value N1 is a rotation speed at which the valve body 32 urged by the elastic member 33 is pressed down (moved) to a position where the discharge port is opened by the hydraulic pressure from the oil supply pump 20. Yes. The rotation speed threshold value N1 can be set by, for example, the elastic force of the elastic member 33 or the axial position of the discharge port 31x. The rotation speed threshold value N1 may be a value within a range of 10 to 50% of the rated rotation frequency of the compressor 1, for example. Note that the rotation speed threshold value N1 is not completely fixed to one value. In different compressors 1, the rotation speed threshold value N1 may be slightly different. Even in the same compressor 1, the rotation speed threshold value N1 may slightly change depending on operating conditions such as the pressure of the refrigerant to be sucked. For example, the valve mechanism 30 may be adjusted so that the rotation speed threshold value N1 is kept within a predetermined range under a specific operating condition.

According to the first embodiment, since excessive lubrication in high-speed operation is suppressed, it is avoided that the space in which the rocking bearing 11a is stored is filled with oil, and the rocking bearing 11a stirs the oil. Power loss due to can be reduced. At this time, the valve mechanism 30 is not attached to the rotary shaft 7 but is provided in the oil supply pump 20, so that power loss can be reduced with a simple structure.

Here, FIG. 7 is a schematic view showing an example of a conventional valve mechanism. As shown in FIG. 7, a valve passage 7z that communicates with the oil supply passage and extends in the radial direction is formed at a position above the oil supply pump of the rotary shaft 7, and a valve body 51 is provided at the outlet of the valve passage 7z. Yes. Therefore, when the rotating shaft 7 rotates, the valve body also rotates simultaneously. For this reason, not only pump pressure but also centrifugal force acts on the valve body 51, and it becomes difficult to control the degree of opening and closing of the valve body 51. Furthermore, since the valve path 7z and the valve body 51 are located in the refrigerant gas space, the oil discharged from the valve path 7z is scattered into the refrigerant gas space inside the sealed container 2.

On the other hand, in the valve mechanism 30 shown in FIGS. 2 to 5, the movement of the valve body 32 is not influenced by the centrifugal force but moves in the axial direction using the pump pressure, and the oil inflow passage 21a and the discharge port 31x are moved. Can be opened and closed. For this reason, it is not necessary to newly attach a valve mechanism to the rotating shaft 7 which is a rotating body, and it can be configured integrally with the oil supply pump 20, and power loss due to oil agitation can be reduced with a simple configuration.

Further, oil return to the oil sump space 2c is performed by the valve body 32 moving in the axial direction to adjust the oil return amount. Therefore, it becomes easy to arrange the discharge port 31x of the valve mechanism 30 in the oil sump space 2c, and when returning oil from the valve mechanism 30 to the oil sump space 2c, mist-like oil is mixed into the refrigerant gas space. Can be prevented. As a result, it is possible to improve the reliability with a small amount of oil rising while reducing the power loss due to the stirring of the oil. Further, even if the operating condition is such that the oil decreases to the lower part of the oil sump space 2c, the oil can be immediately led to the inflow pipe 24 by returning directly to the oil sump space 2c, resulting in insufficient oil supply. Can be prevented.

Furthermore, by applying the configuration of the first embodiment while expanding the excluded volume of the oil supply pump 20, it is possible to suppress both of insufficient oil supply at low speed operation and excessive oil supply at high speed operation. As a result, in low speed operation with a large leakage loss ratio, oil can actively flow into the compression mechanism section to ensure the sealing performance of the gap inside the compressor 1 and reduce leakage loss. it can.

Embodiment 2. FIG.
8 to 10 are schematic views showing an example of the valve mechanism of the compressor according to Embodiment 2 of the present invention. The valve mechanism will be described with reference to FIGS. 8 to 10, the same parts as those of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. FIG. 8 shows a state in low speed operation, FIG. 9 shows a state in medium speed operation, and FIG. 10 shows a state in high speed operation.

8 to 10, in the valve mechanism 130, the housing 31 has a plurality of

discharge ports

131x and 131y arranged on the same straight line in the axial direction (arrow Z direction). In addition, although the

several discharge port

131x, 131y has illustrated about the case where it arrange | positions along with the same straight line, it should just be arrange | positioned in the position where an axial direction differs. The valve body 32 is positioned at different positions in the axial direction according to the position corresponding to the magnitude of the pump pressure, and from the plurality of

discharge ports

131x and 131y to the oil sump space 2c according to the position of the valve body 32. The amount of oil returned is adjusted.

Specifically, during low-speed rotation in FIG. 8, the valve element 32 is positioned at a position where all of the plurality of

discharge ports

131x and 131y are closed. 9 is positioned at a position where the upper discharge port 131x is opened and the lower discharge port 131y is closed. Therefore, oil return is performed from the discharge port 31x and oil return from the discharge port 131y is not performed. At the time of high speed rotation in FIG. 10, the plurality of

discharge ports

131x and 131y are positioned at positions where both are opened, and oil is returned from the

discharge ports

131x and 131y.

FIG. 11 is a graph showing the relationship between the number of revolutions and the amount of oil supply in the valve mechanism of FIGS. As shown in FIG. 11, when the rotational speed is smaller than the rotational speed threshold value N1, the plurality of

outlets

131x and 131y are closed (see FIG. 8), so the amount of oil supply is proportional to the rotational speed. . When the rotational speed is equal to or higher than the first threshold value N11 and smaller than the second threshold value N12, the upper discharge port 131x is opened and 131y is closed (see FIG. 9), so that oil is returned from the discharge port 131x. The amount of refueling decreases by the amount. Further, when the rotational speed is equal to or greater than the second threshold value N12, both of the plurality of

discharge ports

131x and 131y are opened (see FIG. 10), so that only the amount of oil return from the plurality of

discharge ports

131x and 131y. The amount of lubrication becomes smaller.

According to the second embodiment, discontinuous oil supply characteristics as shown in FIG. 6 can be obtained, for example, by changing the total opening area of the

discharge ports

131x and 131y stepwise according to the number of rotations. Thereby, the freedom degree of oil supply design can be improved. Further, even in the case of the second embodiment, as in the first embodiment, the oil return is performed directly from the

discharge ports

131x and 131y to the oil sump space 2c. A small improvement in reliability can be achieved.

Embodiment 3 FIG.
12 to 14 are schematic views showing the shape of the discharge port of the valve mechanism of the compressor according to Embodiment 3 of the present invention. In the third embodiment shown in FIGS. 12 to 14, the same components as those in the first and second embodiments are denoted by the same reference numerals, and the description thereof is omitted.

12, the housing 31 is provided with two

discharge ports

231x and 231y at the same position in the axial direction, and discharge ports 231z are formed at different positions in the axial direction. Therefore, when the rotation speed becomes equal to or higher than the predetermined first threshold value N11, oil corresponding to the total opening area of the

discharge ports

231x and 231y is returned. In addition, although the case where two

discharge ports

231x and 231y are formed on the upper side and one discharge port 231z is formed on the lower side is illustrated, one is located at a different position in the axial direction according to the specification and the like. What is necessary is just to provide the above discharge port.

In FIG. 13, the housing 31 is formed with a rectangular discharge port 231p extending in the axial direction. Then, as the rotational speed increases and the pump pressure increases, the opening area of the discharge port 231p due to the movement of the valve body 32 increases. Therefore, it is possible to obtain an oil supply characteristic in which the oil return amount increases as the rotational speed increases and the pump pressure increases. Further, in FIG. 14, the housing 31 is formed with one discharge port 231r extending in the axial direction and having a different width for each position in the axial direction, for example, having a trapezoidal cross section. Then, the amount of increase in the opening area of the discharge port 231r due to the movement of the valve body 32 decreases as the rotational speed increases and the pump pressure increases. Therefore, it is possible to obtain an oil supply characteristic such that the amount of increase in the oil return amount decreases as the rotational speed increases and the pump pressure increases.

Even in the case of the third embodiment, as in the second embodiment, the degree of freedom in designing the oil supply and the amount of oil return can be further improved. Even in the case of the third embodiment, as in the first embodiment, oil return is performed directly from the discharge ports 231x to 231e to the oil sump space 2c. Therefore, the reliability can be improved.

Embodiment 4 FIG.
15 and 16 are schematic views showing an example of the valve mechanism of the compressor according to Embodiment 4 of the present invention. FIG. 15 shows a state where the compressor is stopped, and FIG. 16 shows a state where the compressor is operating. Further, in the fourth embodiment shown in FIGS. 15 and 16, parts having the same configuration as in the first to third embodiments are denoted by the same reference numerals, and the description thereof is omitted.

15 and 16, the valve mechanism 330 includes a reed valve 331. The holder 21 of the oil supply pump 20 is located in the oil sump space 2c. When the compressor in FIG. 15 is in a stopped state, the oil outlet 21x is not open. On the other hand, when the compressor of FIG. 16 is in an operating state, the reed valve 331 is deformed by the pump pressure, and the oil outlet 21x is opened. Further, as the rotational speed increases, the displacement amount of the reed valve 331 increases as the pump pressure increases, and the opening area of the oil outlet 21x also increases.

FIG. 17 is a graph showing the relationship between the rotation speed of the compressor using the valve mechanism of FIGS. 15 and 16 and the amount of oil supplied by the oil supply pump. As shown in FIG. 17, as the rotational speed increases, the ratio of the amount of oil supplied to the bearing with respect to the amount of oil sucked in the oil supply pump 20 can be continuously reduced. As in the third embodiment, the number and shape of the oil outlets 21x provided in the holder 21 may be changed. Thereby, the freedom degree of oil supply design can be improved.

Even in the case of the fourth embodiment, as in the first embodiment, since oil is returned directly from the oil outlet 21x to the oil sump space 2c, reliability with a small amount of oil rising while reducing power loss. Can be improved. Furthermore, since the valve mechanism 330 is configured only by the reed valve 331, power loss due to oil agitation can be reduced with a simple configuration.

Embodiment 5 FIG.
FIG. 18 is a schematic diagram illustrating an example of an oil supply pump in a compressor according to Embodiment 5 of the present invention. In the oil supply pump and valve mechanism of FIG. 18, the same reference numerals are given to portions having the same configurations as those of the oil supply pump and valve mechanism of FIG.

18, the holder 21 of the oil supply pump 20 has an inclined surface 421 at a site serving as a seat surface on which the reed valve 331 located on the oil outlet 21x is installed. As a result, a load can be applied even in a stopped state (see FIG. 16). Therefore, the predetermined rotation speed threshold value N1 that opens the oil outlet 21x can be set by the angle of the inclined surface 421.

According to the fifth embodiment, as in the fourth embodiment, by providing the inclined surface 421, the degree of freedom in oil supply design can be improved. Further, even in the case of the fifth embodiment, as in the first embodiment, since oil is returned directly from the oil outlet 21x to the oil sump space 2c, the amount of oil rising is small while reducing power loss. Reliability can be improved.

Embodiment 6 FIG.
FIG. 19 is a cross-sectional view showing an example of a compressor according to Embodiment 6 of the present invention. In the compressor 500 of FIG. 19, parts having the same configuration as the compressor 1 of FIG. The compressor in FIG. 19 is a so-called horizontal compressor whose axial direction extends in the horizontal direction (arrow X direction).

As shown in FIG. 19, when the rotary shaft 7 extends in the lateral direction, the oil sump space 2 c and the oil surface are formed in the axial direction (arrow Z direction). The valve mechanism 530 has a pipe 531 that communicates with the oil outlet 21 x, and a discharge port 531 x is formed in the pipe 531. And the discharge port 531x is arrange | positioned below the oil level of the oil sump space 2c, and oil returns directly to the inside of the oil sump space 2c. The inflow pipe 24 also has a shape extending in the axial direction to the lower part of the oil sump space 2c. Thereby, even if it is an operating condition where oil decreases to the lower part of the oil sump space 2c, the oil can be immediately led to the inflow pipe 24, and an insufficient supply of oil can be prevented.

Even in the so-called horizontal compressor 500 as in the sixth embodiment, since oil is returned directly from the oil outlet 21x to the oil sump space 2c as in the first embodiment, power loss is reduced. Therefore, it is possible to improve the reliability with a small amount of oil rising.

The embodiment of the present invention is not limited to the above embodiment, and various modifications can be made. For example, the first to sixth embodiments have been described with respect to the scroll type compressor, but the present invention can also be applied to a compressor having a different compression method such as a rotary type or a vane type. In the first to sixth embodiments, the compressor in which the internal pressure of the sealed container 2 is low is described. However, the same effect can be obtained even in a compressor in which the internal pressure of the sealed container 2 is low.

Furthermore, in FIG. 1, although the case where the oil supply pump 20 and the valve mechanism 30 are accommodated in the oil sump space 2c is illustrated, it may be located above the oil sump space 2c. In this case, a pipe extending from the discharge port 31x of the housing 31 to the bottom of the sealed container 2 may be provided. In the first to sixth embodiments, the oil supply pump 20 is illustrated as a trochoid type positive displacement pump. However, for example, it is a known positive displacement type positive displacement pump such as a vane type. Also good.

1,500 compressor, 2 sealed container, 2a suction pipe, 2b discharge pipe, 2c oil sump space, 3 frame, 3a flow path, 4 subframe, 5 main bearing, 6 sub bearing, 7 rotating shaft, 7a eccentric shaft 7x oil supply path, 7y supply path, 7z valve path, 8 motor, 8a motor rotor, 8b motor stator, 9 slider, 9a first balance weight, 9b second balance weight, 10 compression mechanism, 11 swing scroll , 11a rocking bearing, 11b spiral body, 12 fixed scroll, 12a discharge port, 12b spiral body, 13 baffle, 14 discharge valve, 15 discharge muffler container, 20 oil supply pump, 21 retainer, 21a oil inflow path, 21x oil outlet , 22 Outer rotor, 23 Inner rotor, 24 Inflow pipe, 30 130, 330, 530 valve mechanism, 31 housing, 31a hollow part, 31x discharge port, 32 valve body, 33 elastic member, 51 valve body, 131x, 131y, 231p, 231r, 231x, 231y, 231z, 231x discharge port, 331 Reed valve, 421 inclined surface, 531 piping, N1 rotation threshold, N11 first rotation speed threshold, N12 second rotation speed threshold.

Claims

A sealed container having an oil sump space for storing oil at the bottom;
A compression mechanism that compresses the fluid that is contained in the sealed container and flows into the sealed container;
An electric motor housed in the sealed container and generating a rotational force;
A rotational shaft that transmits a rotational force generated by the electric motor to the compression mechanism portion and has an oil supply passage extending in an axial direction from an end portion therein,
An oil passage that is provided on the end side of the rotary shaft, operates by the rotation of the rotary shaft, sucks the oil in the oil sump space, and supplies the oil to the oil supply passage. And an oil supply pump having an oil outlet provided in the oil flow path,
A valve mechanism provided at the oil outlet;
With
The valve mechanism is
A housing having a hollow portion communicating with the oil outlet, and having a discharge port communicating with the oil sump space;
A valve body housed in the housing and moved by the pressure of the oil at the oil outlet;
Have
When the number of rotations of the rotating shaft exceeds a predetermined value, the oil outlet is opened by the movement of the valve body, and the oil is discharged from the discharge port to the oil sump space,
The discharge port of the valve mechanism is a compressor located in the oil sump space.
The valve mechanism is
The compressor according to claim 1, further comprising an elastic member that is provided between the housing and the valve body and biases the valve body toward the oil outlet side.
The compressor according to claim 2, wherein the housing is formed integrally with the oil supply pump.
The compressor according to claim 2 or 3, wherein the housing is provided with a plurality of discharge ports in the axial direction.
The compressor according to any one of claims 2 to 4, wherein the discharge port has a shape extending in an axial direction.
The compressor according to claim 5, wherein the discharge port is formed so that an opening width becomes narrower from the oil outlet toward the oil sump space.
The oil pump and the valve mechanism are located inside the oil sump space,
The compressor according to claim 1, wherein the valve mechanism includes a valve body that elastically deforms in an axial direction to open and close the oil outlet.
The compressor according to claim 7, wherein an inclined surface for applying a preload to the valve body is formed at an attachment portion of the valve body in the oil pump.
The oil supply pump supplies oil to the oil supply passage at a higher pressure as the number of rotations of the rotary shaft increases.
The valve mechanism closes the oil outlet during low-speed operation when the rotational speed is less than the predetermined value, and opens the oil outlet during high-speed operation when the rotational speed is greater than or equal to the predetermined value. The compressor according to any one of the above.
The compressor according to any one of claims 1 to 9, wherein the oil supply pump is a positive displacement pump.
The compressor according to claim 10, wherein the oil supply pump is a trochoid pump.