WO2017086105A1

WO2017086105A1 - Scroll compressor

Info

Publication number: WO2017086105A1
Application number: PCT/JP2016/081635
Authority: WO
Inventors: 征大谷口; 央幸木全; 創佐藤; 洋悟高須; 陽平堀田; 太一舘石; 拓馬山下; 暉裕金井
Original assignee: 三菱重工業株式会社
Priority date: 2015-11-20
Filing date: 2016-10-25
Publication date: 2017-05-26
Also published as: EP3318759A4; CN107850069B; JP2017096145A; CN107850069A; EP3318759A1

Abstract

A scroll compressor is equipped with: a scroll compression mechanism that is housed in a housing and compresses a low-pressure gas; a motor that is linked to the scroll compression mechanism by a rotary shaft and that drives the scroll compression mechanism; an upper bearing and a lower bearing that support the rotary shaft in a rotatable manner; and an oil supply pump that draws in lubricating oil due to the rotation of the rotary shaft and supplies the lubricating oil to sliding parts. The oil supply pump is a positive-displacement pump which is capable of operating in an operating region wherein the rotational frequency of the motor is 150 rps or higher, and for which an inclination indicating the rate of increase in the amount of oil supplied per unit time with respect to the rotational frequency decreases as the rotational frequency increases.

Description

Scroll compressor

The present invention relates to a scroll compressor used in a refrigeration system, an air conditioner, and the like.

Generally, a scroll compressor having a scroll compression mechanism housed in a housing and a drive motor for driving the scroll compression mechanism is widely known. The scroll compression mechanism includes a fixed scroll member provided with a spiral wrap on one side of a disk-shaped end plate and a turning scroll member, and these fixed scroll and the turning scroll are engaged with the wrap The rotating scroll is made to revolve with respect to the fixed scroll. Then, the volume of the compression space formed between the two wraps is reduced along with the turning of the orbiting scroll to compress the fluid (gas refrigerant) in the space.

In the scroll compressor, lubrication of each sliding portion is required for the purpose of preventing seizing of the scroll compression mechanism and the bearing and cooling thereof. In addition, if fluid leaks from a minute gap between the fixed scroll and the orbiting scroll, this leads to a reduction in the capacity of the compressor. Therefore, the lubricating oil is stored in the bottom of the housing and a lubricating oil pump is provided near the lower end of the rotating shaft of the drive motor, and the lubricating oil pump pumps up the lubricating oil by the rotation of the rotating shaft and supplies it to each sliding portion In the related art, there has been proposed a scroll compressor capable of changing the amount of lubricating oil supplied in accordance with the number of revolutions of a drive motor (for example, see Patent Document 1).

The lubricating oil pumped up by the lubricating oil pump is circulated to the inside of the housing by being dropped and returned to the bottom of the housing after being supplied to each sliding portion. At this time, the fluid introduced into the housing is sucked between the fixed scroll and the orbiting scroll while rolling up the lubricating oil, so that the lubricating oil mixes with the fluid. For this reason, the lubricating oil mixed in the fluid seals a minute gap between the fixed scroll and the wrap of the orbiting scroll, thereby suppressing the decrease in the operating efficiency of the compressor.

Unexamined-Japanese-Patent No. 08-177773 gazette

By the way, in recent years, there is a demand for improvement of the capacity of a refrigeration system or an air conditioning system using a scroll compressor. For this reason, it has been studied to operate in a wider rotation speed region by raising the upper limit value of the rotation speed (operating frequency) of the scroll compressor from 100 to 140 rps (for example, 150 rps or more). In this case, the following conditions (A) and (B) need to be satisfied from the viewpoint of supplying the lubricating oil.

(A) For example, at a low speed operation of about 50 rps, it is necessary to supply a sufficient amount of lubricating oil to each sliding portion in order to seal the gap between the wraps and to suppress the decrease in the operation efficiency. On the other hand, (B), for example, during high-speed operation of 150 rps or more, if the amount of lubricating oil discharged to the outside of the housing with the fluid increases, the lubricating oil stored in the housing may run short. It is necessary to reduce the amount of lubricating oil. However, increasing the amount supplied to each sliding portion generally increases the amount of lubricating oil discharged, so it is difficult to make the above conditions (A) and (B) compatible.

The present invention has been made in view of the above circumstances, and is a scroll compression that can suppress the reduction in the operating efficiency of the compressor during low speed operation and can reduce the amount of lubricating oil discharged from the compressor during high speed operation. The purpose is to provide a machine.

In order to solve the problems described above and achieve the object, the present invention relates to a housing into which low pressure gas flows, a scroll compression mechanism housed in the housing to compress low pressure gas, and a scroll compression mechanism and drive shaft The lubricating oil stored in the bottom of the housing is pumped up by rotation of the drive shaft and the drive motor for driving the scroll compression mechanism, the bearing for rotatably supporting the drive shaft, and the scroll compression mechanism and bearing The lubricating oil pump is operable in an operating range where the number of revolutions of the drive motor is at least 150 rps or more, and the rate of increase of the amount of oil supply per unit time with respect to the number of revolutions. It is characterized in that it is a positive displacement pump in which the inclination indicating the velocity decreases as the rotation speed increases.

According to this configuration, it is possible to realize a reduction in the operating efficiency of the compressor during low speed operation and a reduction in the amount of lubricating oil discharged from the compressor during high speed operation, and an operation in a wider rotation speed range Is possible. In addition, since low pressure gas flows into the housing, the pressure difference between the lubricating oil pump and each sliding portion can be kept small, and excessive supply of lubricating oil due to differential pressure is prevented. it can.

The lubricating oil pump is driven when the pump oil supply amount per rotation of the lubricating oil pump is Q (cc / rev) and the scroll displacement amount per rotation of the scroll compression mechanism is Vs (cc / rev). In the operating range where the number of revolutions of the motor is from 0 rps to 60 rps, Q / Vs> 0.006 is satisfied, and in the operating range where the number of rotations of the drive motor is at least 150 rps to 200 rps, 0.003 ≦ Q / Vs ≦ 0. It is preferable to satisfy 006. According to this configuration, the amount of lubricating oil supplied to each sliding portion can be sufficiently secured at the low speed operation, and the amount of lubricating oil supplied at the high speed operation can be suppressed.

In addition, it has an oil supply passage through which the lubricating oil supplied to the sliding portion flows, and a return oil passage for returning the surplus lubricating oil supplied to the sliding portion back into the housing, and the minimum diameter in the oil supply passage is d1 Assuming that the equivalent diameter of the oil passage is d2 and the inner diameter of the suction port of the lubricating oil pump is D, the inner diameter D of the suction port may satisfy d1 ≦ D ≦ d2. According to this configuration, since the minimum diameter d1 in the oil supply passage is equal to or less than the inner diameter D of the suction port, the lubricating oil pumped up by the lubricating oil pump can be reliably supplied to the sliding portion. Further, since the equivalent diameter d2 of the return oil passage is equal to or larger than the inner diameter D of the suction port, surplus lubricating oil is prevented from staying in the return oil passage, and the lubricating oil stored in the bottom of the housing runs short. Can be prevented.

Also, the lubricating oil pump may be a rolling piston lubricating oil pump. According to this configuration, since the rolling piston type lubricating oil pump causes a suction loss at high speed rotation, the amount of oil supply at high speed operation of the compressor can be effectively suppressed.

According to the present invention, the lubricating oil pump can be operated in the operating range where the number of revolutions of the drive motor is at least 150 rps or more, and the inclination indicating the rate of increase of the amount of oil supply per unit time with respect to the number of revolutions is the number of revolutions. As the displacement pump is smaller as it becomes larger, it is possible to realize a reduction in the operating efficiency of the compressor at low speed operation and a reduction in the amount of lubricating oil discharged from the compressor at high speed operation. Operation in the rotational speed range is possible.

FIG. 1 is an overall cross-sectional view of a scroll compressor according to the present embodiment. FIG. 2 is a cross-sectional view of an oil supply pump provided in the scroll compressor. FIG. 3 is a graph showing the relationship between the pump oil supply amount Q / scroll displacement amount Vs and the rotational speed of the drive motor. FIG. 4 is a graph showing the relationship between the amount of oil supplied per unit time of the pump and the number of rotations of the drive motor.

Hereinafter, embodiments according to the present invention will be described in detail based on the drawings. The present invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily replaced by persons skilled in the art or those that are substantially the same.

FIG. 1 is an overall cross-sectional view of a scroll compressor according to the present embodiment. The scroll compressor 1 compresses and discharges a sucked fluid (for example, refrigerant), and in the present embodiment, is interposed in a refrigerant flow path that circulates the refrigerant in an air conditioner, a refrigeration apparatus, or the like.

As shown in FIG. 1, the scroll compressor 1 includes a motor (drive motor) 5 as drive means and a scroll compression mechanism 7 driven by the motor 5 in a housing 3.

The housing 3 includes a cylindrical housing body 3a extending vertically, a bottom 3b closing the lower end of the housing body 3a, and a lid 3c closing the upper end of the housing body 3a, and the whole is sealed. It is a pressure vessel. The housing body 3a is provided at its side with a suction pipe 9 for introducing a refrigerant (low pressure gas) into the housing 3. The lid 3 c is provided at its upper portion with a discharge pipe 11 for discharging the refrigerant (high pressure gas) compressed by the scroll compression mechanism 7. In the housing 3, the discharge cover 13 is provided between the housing main body 3 a and the lid 3 c, and the inside of the housing 3 is the low pressure chamber 3 A below the discharge cover 13 and the high pressure chamber 3 B above the discharge cover 13. Divided into The discharge cover 13 has an opening 13a communicating the low pressure chamber 3A with the high pressure chamber 3B, and a discharge reed valve 13b opening and closing the opening 13a. The bottom in the housing 3 (low pressure chamber 3A) is configured as an oil reservoir 41 in which the lubricating oil 40 is stored.

The motor 5 includes a stator 15, a rotor 17, and a rotating shaft (drive shaft) 19. The stator 15 is fixed to the inner wall surface of the housing main body 3a substantially at the center in the vertical direction of the housing main body 3a. The rotor 17 is rotatably provided with respect to the stator 15. The rotating shaft 19 is disposed up and down in the longitudinal direction with respect to the rotor 17. The motor 5 rotates the rotor 17 when power is supplied from the outside of the housing 3, and the rotating shaft 19 rotates with the rotor 17. In the present embodiment, the motor 5 is configured to be able to control the operating frequency by, for example, an inverter (not shown), and can operate in a wide range from the low rotation speed region to the high rotation speed region.

The rotating shaft 19 has end portions projecting upward and downward of the rotor 17, and the upper end portion of the housing main body 3a is vertically moved by the upper bearing 21 and the lower end portion is vertically moved by the lower bearing 23. It is rotatably supported on the axis CE extending in the direction. The rotating shaft 19 is formed at its upper end with an eccentric pin 25 projecting upward along the eccentricity LE which is biased with respect to the axial center CE. The scroll compression mechanism 7 is connected to the upper end of the rotary shaft 19 having the eccentric pin 25. In addition, the rotary shaft 19 and the eccentric pin 25 are formed therein with a fueling hole (fueling passage) 27 penetrating vertically. The oil supply hole 27 communicates with the oil supply hole 27 at a height position corresponding to the upper bearing 21 and the lower bearing 23, and penetrates in the radial direction of the rotary shaft 19 with the upper oil supply hole (oil supply passage) 27a. A (fuel supply passage) 27b is provided. Further, at the lower end of the rotating shaft 19, an oil supply pump (lubricating oil pump) 29 disposed in the oil reservoir 41 is provided. The oil supply pump 29 pumps up the lubricating oil 40 stored in the oil reservoir 41 as the rotary shaft 19 rotates. Lubricated oil is pumped to the sliding portion between the upper bearing 21 and the lower bearing 23 and the rotating shaft 19 and the scroll compression mechanism 7 through the oil supply hole 27, the upper oil supply hole 27 a and the lower oil supply hole 27 b of the rotary shaft 19. Supplied.

The upper bearing 21 penetrates the upper end portion of the rotating shaft 19 to rotatably support the rotating shaft 19. The upper bearing 21 has a recess 21 a formed on the upper surface thereof so as to surround the upper end portion of the rotary shaft 19 penetrated. The recess 21 a accommodates a slide bush 37 described later, and stores the lubricating oil 40 fed by the oil supply pump 29 through the oil supply hole 27. Then, the stored lubricating oil 40 is supplied to the scroll compression mechanism 7.

In the upper bearing 21, a notch 21 b is formed on a part of the outer periphery so as to have a gap with the inner wall surface of the housing main body 3 a of the housing 3, and the oil drainage hole (return oil passage communicating the notch 21 b and the recess 21 a ) 21c is formed. Further, below the notch 21 b of the upper bearing 21, a cover plate 31 is provided. The cover plate 31 is provided to extend in the vertical direction. The cover plate 31 is formed by curving both ends toward the inner wall surface of the housing main body 3a so as to cover the periphery of the notch 21b, and the lower end is bent so as to gradually approach the inner wall surface of the housing main body 3a It is done. Then, the oil drain hole 21 c discharges the lubricating oil 40 surplusly stored in the recess 21 a from the notch 21 b to the outer periphery of the upper bearing 21. The cover plate 31 receives the lubricating oil 40 discharged from the notch 21b and guides it toward the inner wall surface of the housing main body 3a. The lubricating oil 40 guided toward the inner wall surface by the cover plate 31 is returned to the oil reservoir 41 at the bottom of the housing 3 along the inner wall surface by the cover plate 31.

The scroll compression mechanism 7 is disposed inside the housing 3 in the low pressure chamber 3A lower than the discharge cover 13 and above the upper bearing 21 and fixed scroll 33, orbiting scroll 35 and slide bush 37. And.

In the fixed scroll 33, a spiral fixed side wrap 33b is formed on the inner surface (lower surface in FIG. 1) of the fixed side end plate 33a fixed inside the housing 3. The fixed end plate 33a has a discharge hole 33c at its center.

In the orbiting scroll 35, a spiral movable side wrap 35b is formed on the inner surface (upper surface in FIG. 1) of the movable side end plate 35a facing the inner surface of the fixed side end plate 33a in the fixed scroll 33. Then, the movable side wrap 35b of the orbiting scroll 35 and the fixed side wrap 33b of the fixed scroll 33 are engaged with each other while being out of phase with each other, whereby the compression divided by the

end plates

33a, 35a and the

respective wraps

33b, 35b A room is formed. Further, the orbiting scroll 35 has a cylindrical boss 35c to which the eccentric pin 25 of the rotating shaft 19 is connected to the outer surface (the lower surface in FIG. 1) of the movable side end plate 35a and the eccentric rotation of the eccentric pin 25 is transmitted. Is formed. Further, the orbiting scroll 35 is prevented from rotating on the basis of the eccentric rotation of the eccentric pin 25 by a rotation preventing mechanism 39 such as a known Oldham link arranged between the outer surface of the movable side end plate 35a and the upper bearing 21. While being revolved.

The slide bush 37 is accommodated in the recess 21 a of the upper bearing 21 described above, and is interposed between the eccentric pin 25 of the rotating shaft 19 and the boss 35 c of the orbiting scroll 35 to rotate the eccentric pin 25 of the orbiting scroll 35. It is transmitted as a turning movement. The slide bush 37 is provided slidably in the radial direction of the eccentric pin 25 in order to maintain the meshing between the movable side wrap 35 b of the orbiting scroll 35 and the fixed side wrap 33 b of the fixed scroll 33.

In the scroll compression mechanism 7, the low-pressure refrigerant introduced into the low-pressure chamber 3 </ b> A in the housing 3 via the suction pipe 9 is compressed between the fixed scroll 33 and the orbiting scroll 35 by the orbiting scroll 35 revolving. It is compressed while being inhaled into the room. Here, a part of the lubricating oil 40 discharged into the housing 3 through the oil drain hole 21 c is wound up by the low-pressure refrigerant in the low-pressure chamber 3A, mixed with the low-pressure refrigerant and fixed scroll 33 and It is drawn between the orbiting scroll 35 and is supplied to the sliding portion between the fixed scroll 33 and the orbiting scroll 35. Therefore, the lubricating oil 40 mixed in the refrigerant seals the minute gap between the

respective wraps

33b and 35b, thereby preventing the refrigerant from leaking from the gap and suppressing the decrease in the operation efficiency of the scroll compressor 1 doing.

The compressed high-pressure refrigerant is discharged from the discharge hole 33c of the fixed scroll 33 to the outer surface side of the fixed end plate 33a, and the discharge reed valve 13b of the discharge cover 13 is opened by its own pressure, and the high pressure chamber is opened from the opening hole 13a. It reaches 3 B and is discharged to the outside of the housing 3 through the discharge pipe 11.

By the way, in the refrigeration apparatus and air conditioning apparatus using the scroll compressor 1 in recent years, there is a tendency for improvement of refrigeration capacity or air conditioning capacity to be demanded. Generally, in scroll compressors, it is known that the upper limit value of the rotational speed (operating frequency) is 100 to 140 rps, but this upper limit value is increased (for example, 150 rps or more) to increase the rotational speed range. It is considered to drive at. In order to widen the operable rotational speed range, first, from the viewpoint of supplying lubricating oil, first, at low speed operation (low rotational range) of about 50 rps, for example, the gaps between the

wraps

33b and 35b are sealed. It is necessary to supply a sufficient amount of lubricating oil 40 to each sliding portion in order to suppress a decrease in operating efficiency. Second, for example, during high-speed operation (high rotation area) of 150 rps or more, the amount of lubricating oil 40 discharged to the outside of the housing 3 along with the refrigerant increases, so the lubrication stored in the housing 3 In order to prevent the shortage of the amount of oil, it is necessary to suppress the amount of lubricating oil discharged. However, in general, when the supply amount of the lubricating oil 40 is increased by increasing the rotational speed of the motor 5, the amount of the lubricating oil discharged to the outside of the housing 3 also increases, so the first and second conditions described above are satisfied. It was difficult to make it compatible. The scroll compressor 1 according to the present embodiment achieves both suppression of decrease in operating efficiency at low speed operation and reduction of the amount of lubricating oil discharged to the outside of the housing 3 at high speed operation.

FIG. 2 is a cross-sectional view of the fuel pump. The oil supply pump 29 is a so-called rolling piston (positive displacement) oil supply pump, and as shown in FIG. The feed pump 29 includes a cylinder chamber 45 whose lower opening is sealed by a cover body 44 attached to the bottom of the lower bearing 23. The cover body 44 integrally includes a suction nozzle 43 extending downward, and the suction nozzle 43 is formed with a suction port 43A communicating with the cylinder chamber 45. In the cylinder chamber 45, as shown in FIG. 1 and FIG. 2, a rotor 47 fitted in an eccentric shaft portion 46 formed at the lower end of the rotating shaft 19 is accommodated. With the rotation, the inner circumferential surface of the cylinder chamber 45 is in sliding contact with the cylinder chamber 45 and revolves and turns. As shown in FIG. 2, the rotor 47 is integrally provided with a blade 47A that divides the inside of the cylinder chamber 45 into an oil supply chamber 45A and an oil discharge chamber 45B. The lubricating oil 40 accumulated in the oil reservoir 41 is sucked into the oil supply chamber 45A through the suction port 43A of the suction nozzle 43 and the oil supply port 48 by the revolving motion of the rotor 47, and is discharged from the oil discharge chamber 45B to the oil discharge port 49. The air is sent to the oil supply hole 27 of the rotary shaft 19 through the communication passage 50 (see FIG. 1). Since the rolling piston type oil supply pump 29 generates suction loss at high speed rotation, the amount of oil supply at high speed operation of the motor 5 (compressor 1) can be effectively suppressed. The above-described rolling piston type oil supply pump 29 is merely an example, and as long as it is a positive displacement type oil supply pump, an oil supply pump having another configuration may be adopted.

As described above, the lubricating oil 40 pumped up by the lubricating pump 29 through the suction port 43A flows through the oil supply hole 27 of the rotary shaft 19, and a part of the lubricating oil 40 flows through the upper oil supply hole 27a and the lower oil supply hole 27b. The sliding parts of the upper bearing 21 and the lower bearing 23 and the rotary shaft 19 are respectively supplied. Further, a part of the lubricating oil 40 is stored in the recess 21 a of the upper bearing 21 and supplied to the sliding portion between the recess 21 a and the orbiting scroll 35, and the excess lubricating oil 40 is discharged through the oil drainage hole 21 c. It is returned to the oil reservoir 41.

In the present embodiment, the inner diameter D of the suction port 43A of the oil supply pump 29 is the minimum diameter d1 of the oil supply hole 27 including the upper oil supply hole 27a and the lower oil supply hole 27b, and the equivalent diameter d2 of the oil discharge hole 21c; It is in a relationship that satisfies d2.

Here, the smallest diameter d1 of the oil supply hole 27 refers to the narrowest portion of the inner diameter of the oil supply hole 27 for supplying the sliding portion (upper bearing 21, recess 21a, lower bearing 23) from the oil supply pump 29. No, in this embodiment, the inner diameters of the upper fuel hole 27a and the lower fuel hole 27b are the minimum diameter d1. The equivalent diameter d2 of the oil drain hole 21c is a parameter represented by d2 = 4 × A / L, where A is the sectional area of the oil drain hole 21c and L is the outer length of the oil drain hole 21c. .

According to this configuration, the minimum diameter d1 (the inner diameter of the upper oil supply hole 27a and the lower oil supply hole 27b) in the oil supply hole 27 is equal to or less than the inner diameter D of the suction port 43A, so the lubricating oil 40 pumped up by the oil supply pump 29 is assured Can be supplied to the sliding portion between the upper bearing 21 and the lower bearing 23 and the rotating shaft 19. Further, since the equivalent diameter d2 of the oil drain hole 21c is equal to or larger than the inner diameter D of the suction port 43A, the excess lubricating oil 40 is prevented from staying in the recess 21a and the oil drain hole 21c. It is possible to prevent the shortage of the lubricating oil stored in the oil reservoir 41 at the bottom.

In general, although the pressure loss tends to increase as the rotational speed increases, the positive displacement feed pump 29 is configured so that the inner diameter D of the suction port 43A of the feed pump 29 satisfies d1 ≦ D ≦ d2. The losses can be greater.

FIG. 3 is a graph showing the relationship between the pump oil supply amount Q and the rotational speed of the motor with respect to the scroll displacement amount Vs. Moreover, FIG. 4 is a graph which shows the relationship between the amount of refueling per unit time of a pump, and the rotation speed of a motor. The pump oil supply amount Q (cc / rev) is a value indicating the amount of oil supply (discharge) per one rotation of the oil supply pump 29, and the scroll displacement amount Vs (cc / rev) is per one rotation of the scroll compression mechanism 7. It is a value indicating the amount of ink that can be pushed out (discharged). In the present embodiment, the theoretical value of the pump oil supply amount Q / scroll displacement amount Vs in the oil supply pump 29 is 0.008.

It is FIG. 3 which measured the pump oil supply amount Q (cc / rev) of the oil supply pump 29 which has the above-mentioned performance in the state which changed rotation speed. As shown in FIG. 3, the measured value of the pump oil supply amount Q / scroll displacement amount Vs tends to decrease as the rotation speed of the motor 5 becomes larger than the theoretical value. Specifically, during low speed operation (low rotation range) where the number of revolutions of the motor 5 is 0 rps or more and 60 rps or less, Q / Vs> 0.006 is satisfied while the number of revolutions of the motor 5 is at least 150 rps During high-speed operation (high rotation range) at not less than 200 rps or more, reduction to a range satisfying 0.003 ≦ Q / Vs ≦ 0.006 is made. In general, the OCR (the ratio of the amount of discharged oil to the refrigerant circulation amount) tends to increase exponentially with the number of rotations of the motor 5 (compressor). For this reason, when the rotational speed of the motor 5 is in the range of 0 rps to 60 rps, the OCR becomes small, and the amount of the amount of oil supplied by the oil supply pump 29 greatly affects the efficiency.

In this configuration, since the pump oil supply amount Q / scroll displacement Vs at the low speed operation satisfies Q / Vs> 0.006, as shown in FIG. 4, the oil supply amount V per unit time at the low speed operation The measured value of (cc / s) can keep the deviation from the theoretical value small. Therefore, the amount of the lubricating oil mixed in the refrigerant can be sufficiently secured, and the lubricating oil seals the minute gap between the

wraps

33b and 35b to prevent the refrigerant from leaking from the gap Thus, it is possible to suppress the decrease in the operating efficiency of the scroll compressor 1. When the pump oil supply amount Q / scroll displacement amount Vs at the time of low speed operation is Q / Vs ≦ 0.006, a sufficient amount of lubrication to seal the minute gap between the

wraps

33 b and 35 b described above Oil can not be supplied, which leads to a reduction in the operating efficiency of the scroll compressor 1.

On the other hand, since the pump oil supply amount Q / scroll displacement Vs at the high speed operation satisfies 0.003 ≦ Q / Vs ≦ 0.006, as shown in FIG. 4, the oil supply per unit time at the high speed operation The measured value of the amount V (cc / s) can make the deviation from the theoretical value larger than that at low speed operation. For this reason, the amount of oil supply V (cc / s) per unit time during high speed operation can be reduced, and accordingly, the amount of lubricating oil discharged from the scroll compressor 1 can be reduced. Therefore, it is possible to realize a reduction in the operating efficiency of the scroll compressor 1 at the time of low speed operation and a reduction in the amount of lubricating oil discharged from the scroll compressor 1 at the high speed operation. Can be realized.

In this embodiment, the pump oil supply amount Q / scroll displacement amount Vs at the time of high speed operation is configured to satisfy 0.003 ≦ Q / Vs ≦ 0.006, but the range of Q / Vs <0.003 is satisfied. In this case, since the amount of lubricating oil supplied to each sliding portion is reduced, cooling failure of the scroll compression mechanism 7, the upper bearing 21, and the lower bearing 23 is caused, and the seizure of the scroll compression mechanism 7, the upper bearing 21, and the lower bearing 23 May occur. In the range of 0.006 <Q / Vs, the amount of lubricating oil supplied from the oil supply pump 29 increases, and the amount of lubricating oil discharged from the scroll compressor 1 increases. As a result, the housing 3 is produced. If the amount of lubricating oil stored in the interior is reduced, cooling failure of the scroll compression mechanism 7, the upper bearing 21, and the lower bearing 23 may be caused, and seizing of the scroll compression mechanism 7, the upper bearing 21, and the lower bearing 23 may occur. is there.

Further, in the present embodiment, as shown in FIG. 4, in the graph of the measured value of the oil supply amount V per unit time, the inclination θ indicating the increase rate of the oil supply amount decreases as the rotation speed increases. . Therefore, not only the supply amount of the lubricating oil can be suppressed at the high speed operation, but also the supply amount of the lubricating oil to each sliding portion can be sufficiently ensured at the low speed operation.

As mentioned above, although one Embodiment of this invention was described, this embodiment is shown as an example and it is not intending limiting the range of invention. This embodiment can be implemented in other various forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. The present embodiment and the modifications thereof are included in the invention described in the claims and the equivalents thereof as well as included in the scope and the gist of the invention.

1 scroll compressor 3 housing 3a housing body 5 motor (drive motor)
7 scroll compression mechanism 9 suction pipe 11 discharge pipe 13 discharge cover 19 rotating shaft (drive shaft)
21 Upper bearing (bearing)
21c Oil drain hole (return oil passage)
23 Lower bearing (bearing)
27 refueling hole (refueling passage)
27a Upper oil supply hole (oil supply passage)
27b Lower oil supply hole (oil supply passage)
29 Oil supply pump (lubricating oil pump)
31 cover plate 33 fixed scroll 33a fixed side plate 33b fixed side wrap 33c discharge hole 35 orbiting scroll 35a movable side plate 35b movable side wrap 35c boss 37 slide bush 39 rotation prevention mechanism 40 lubricating oil 41 oil reservoir 43 suction nozzle 43A suction Port 44 Cover body 45 Cylinder chamber 45A Oil supply chamber 45B Oil discharge chamber 46 Eccentric shaft 47 Rotor 47A Blade 48 Oil supply port 49 Oil outlet 50 Communication passage D Inner diameter d1 Minimum diameter d2 Equivalent diameter

Claims

A housing into which low pressure gas flows,
A scroll compression mechanism housed in the housing for compressing the low pressure gas;
A drive motor coupled to the scroll compression mechanism by a drive shaft to drive the scroll compression mechanism;
A bearing portion rotatably supporting the drive shaft;
A lubricant oil pump that pumps up lubricant oil stored in the bottom of the housing by rotation of the drive shaft and supplies the lubricant to the scroll compression mechanism and the sliding parts of the bearing;
The lubricating oil pump can be operated in an operating range where the number of revolutions of the drive motor is at least 150 rps or more, and the inclination indicating the rate of increase of the amount of oil supply per unit time to the number of revolutions increases as the number of revolutions increases. A scroll compressor characterized by being a positive displacement pump.
The lubricating oil pump has a pump oil supply amount per rotation of the lubricating oil pump as Q (cc / rev) and a scroll displacement amount per rotation of the scroll compression mechanism as Vs (cc / rev),
In an operating range where the number of revolutions of the drive motor is from 0 rps to 60 rps,
Q / Vs> 0.006
The filling,
In an operating range where the number of rotations of the drive motor is at least 150 rps and less than 200 rps,
0.003 ≦ Q / Vs ≦ 0.006
The scroll compressor according to claim 1, wherein:
The oil supply passage through which the lubricating oil supplied to the sliding portion flows, and the return oil passage for returning the surplus lubricating oil supplied to the sliding portion back into the housing,
Assuming that the minimum diameter in the oil supply passage is d1, the equivalent diameter of the return oil passage is d2, and the inner diameter of the suction port of the lubricating oil pump is D:
The inner diameter D of the suction port of the lubricating oil pump is
d1 ≦ D ≦ d2
The scroll compressor according to claim 1 or 2, characterized in that
The scroll compressor according to any one of claims 1 to 3, wherein the lubricating oil pump is a rolling piston lubricating oil pump.