JP2017096145A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll compressor capable of suppressing deterioration of operation efficiency of a compressor during low speed operation, and capable of reducing an amount of lubricating oil discharged from the compressor during high speed operation.SOLUTION: A scroll compressor includes a scroll compression mechanism stored in a housing and compressing low pressure gas, a motor connected with the scroll compression mechanism by a rotary shaft and driving the scroll compression mechanism, an upper bearing and a lower bearing rotatably supporting the rotary shaft, and an oil supply pump for pumping lubricating oil so as to supply the lubricating oil to sliding parts by rotation of the rotary shaft. The oil supply pump is a positive displacement pump, and can be operated in an operation region where a rotation speed of the motor is at least 150 rps or more, and a slope representing an increase rate of an oil supply amount per unit time to the rotation speed is reduced as the rotation speed becomes large.SELECTED DRAWING: Figure 4

Description

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

  In general, a scroll compressor including a scroll compression mechanism housed in a housing and a drive motor that drives the scroll compression mechanism is widely known. The scroll compression mechanism includes a fixed scroll member having a spiral wrap provided on one surface side of a disk-shaped end plate and a orbiting scroll member. The fixed scroll and the orbiting scroll are engaged with each other. The orbiting scroll revolves with respect to the fixed scroll. And the volume of the compression space formed between both laps is decreased with the turning of the orbiting scroll, so that the fluid (gas refrigerant) in the space is compressed.

  In a scroll compressor, lubrication of each sliding part is required for the purpose of preventing or cooling the scroll compression mechanism and the bearing. Moreover, if fluid leaks from a minute gap between the wraps of the fixed scroll and the orbiting scroll, the capacity of the compressor is reduced. Therefore, lubricating oil is stored at 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. Conventionally, there has been proposed a configuration in which the supply amount of lubricating oil can be varied in accordance with the rotational speed of the drive motor (see, for example, Patent Document 1).

  The lubricating oil pumped up by the lubricating oil pump is supplied to each sliding portion and then dropped and returned to the bottom of the housing to circulate in the housing. At this time, the fluid introduced into the housing is sucked in between the fixed scroll and the orbiting scroll while winding up the lubricant, so that the lubricant is mixed into the fluid. For this reason, the lubricating oil mixed in the fluid seals a minute gap between the laps of the fixed scroll and the orbiting scroll, thereby suppressing a reduction in operating efficiency of the compressor.

JP 08-177773 A

  Incidentally, in recent years, there has been a demand for an improvement in the capacity of a refrigeration apparatus and an air conditioner using a scroll compressor. For this reason, it is considered that the upper limit value of the rotation speed (operation frequency) of the scroll compressor is increased from the conventional 100 to 140 rps (for example, 150 rps or more) and the operation is performed in a wider rotation speed range. In this case, it is necessary to satisfy the following conditions (A) and (B) from the viewpoint of supplying the lubricating oil.

  (A) For example, during 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 laps and suppress the decrease in operating efficiency. On the other hand, (B) For example, during high-speed operation of 150 rps or higher, if the amount of lubricating oil discharged to the outside of the housing together with the fluid increases, there is a risk that the lubricating oil stored in the housing may be insufficient, and thus discharged. It is necessary to reduce the amount of lubricating oil. However, if the supply amount to each sliding part is increased, generally the amount of lubricating oil to be discharged also increases, so it has been difficult to satisfy both the above conditions (A) and (B).

  The present invention has been made in view of the above circumstances, and is a scroll compression capable of realizing 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. The purpose is to provide a machine.

  In order to solve the above-described problems and achieve the object, the present invention includes a housing into which low-pressure gas flows, a scroll compression mechanism that is housed in the housing and compresses low-pressure gas, and is connected to the scroll compression mechanism by a drive shaft. A drive motor that drives the scroll compression mechanism; a bearing portion that rotatably supports the drive shaft; and a rotation of the drive shaft to pump up lubricant stored in the bottom of the housing, thereby A lubricating oil pump for supplying to each sliding portion, and the lubricating oil pump can be operated in an operating region where the rotational speed of the drive motor is at least 150 rps or more, and the rate of increase in the amount of oil supply per unit time with respect to the rotational speed This is a positive displacement pump that has a slope that decreases as the rotational speed increases.

  According to this configuration, it is possible to achieve 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 operation in a wider rotational 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 part can be kept small, preventing excessive supply of lubricating oil due to the differential pressure. it can.

  The lubricating oil pump is driven when the amount of pump oil supplied per rotation of the lubricating oil pump is Q (cc / rev) and the scroll displacement per rotation of the scroll compression mechanism is Vs (cc / rev). Q / Vs> 0.006 is satisfied in the operating range where the motor speed is 0 rps to 60 rps, and 0.003 ≦ Q / Vs ≦ 0. 0 in the operating range where the rotational speed of the drive motor is at least 150 rps to 200 rps. It is preferable to satisfy 006. According to this configuration, it is possible to suppress the supply amount of the lubricating oil during the high speed operation while sufficiently securing the supply amount of the lubricating oil to each sliding portion during the low speed operation.

  In addition, an oil supply passage through which the lubricating oil supplied to the sliding portion flows and a return oil passage for returning the excess lubricating oil supplied to the sliding portion into the housing are d1 as the minimum diameter in the oil supply passage. When 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 smaller 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, excess lubricant oil is prevented from staying in the return passage, and the lubricant oil stored at the bottom of the housing is insufficient. Can be prevented.

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

  According to the present invention, the lubricating oil pump can be operated in an operation region where the rotational speed of the drive motor is at least 150 rps or more, and the slope indicating the rate of increase in the amount of oil supply per unit time with respect to the rotational speed is Since it is a positive displacement pump that becomes smaller as it grows larger, it can 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. Operation in the rotation speed range is possible.

FIG. 1 is an overall cross-sectional view of the 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 / the 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 rotational speed of the drive motor.

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

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

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

  The housing 3 includes a cylindrical housing body 3a that extends vertically, a bottom 3b that closes the lower end of the housing body 3a, and a lid 3c that closes the upper end of the housing body 3a, and is entirely sealed. It is a pressure vessel. The housing main body 3a is provided with a suction pipe 9 for introducing a refrigerant (low pressure gas) into the housing 3 at a side portion thereof. The lid 3c is provided with a discharge pipe 11 at the top thereof for discharging the refrigerant (high pressure gas) compressed by the scroll compression mechanism 7. The housing 3 is provided with a discharge cover 13 between the housing main body 3a and the lid 3c, and the interior of the housing 3 includes a low pressure chamber 3A below the discharge cover 13 and a high pressure chamber 3B above the discharge cover 13. It is divided into and. The discharge cover 13 is formed with an opening hole 13a that connects the low pressure chamber 3A and the high pressure chamber 3B, and a discharge reed valve 13b that opens and closes the opening hole 13a. The bottom of the housing 3 (low pressure chamber 3A) is configured as an oil reservoir 41 in which the lubricating oil 40 is accumulated.

  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 at substantially the center in the vertical direction of the housing main body 3a. The rotor 17 is provided to be rotatable with respect to the stator 15. The rotating shaft 19 is arranged vertically 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 together with the rotor 17. In the present embodiment, the motor 5 is configured such that the operation frequency can be controlled by, for example, an inverter (not shown), and can be operated in a wide range from a low rotation speed region to a high rotation speed region.

  The rotating shaft 19 is provided with an end protruding above and below the rotor 17, and the upper end of the rotating shaft 19 is vertically moved by an upper bearing (bearing portion) 21 and the lower end is lowered by a lower bearing (bearing portion) 23. It is rotatably supported on the basis of an axial center CE extending in the direction. An eccentric pin 25 is formed at the upper end of the rotating shaft 19 and protrudes upward along an eccentric LE that is offset with respect to the axis 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 with an oil supply hole (oil supply passage) 27 penetrating vertically. The oil supply holes 27 are located at heights corresponding to the upper bearing 21 and the lower bearing 23, and communicate with the oil supply holes 27 and penetrate in the radial direction of the rotary shaft 19. (Oil supply passage) 27b is provided. An oil supply pump (lubricating oil pump) 29 disposed in the oil reservoir 41 is provided at the lower end of the rotary shaft 19. The oil supply pump 29 pumps up the lubricating oil 40 stored in the oil reservoir 41 as the rotary shaft 19 rotates. The pumped lubricating oil passes 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, and slides between the upper bearing 21 and the lower bearing 23 and the rotary shaft 19 and the scroll compression mechanism 7. Supplied.

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

  Further, the upper bearing 21 has a notch 21b formed in a part of the outer periphery so as to have a gap with the inner wall surface of the housing body 3a of the housing 3, and an oil drain hole (return oil passage) that communicates the notch 21b with the recess 21a. ) 21c is formed. A cover plate 31 is provided below the notch 21 b of the upper bearing 21. The cover plate 31 is provided extending in the vertical direction. The cover plate 31 is formed to bend toward the inner wall surface of the housing body 3a so as to cover the periphery of the notch 21b, and is bent so that the lower end gradually approaches the inner wall surface of the housing body 3a. Has been. The oil drain hole 21c discharges the lubricating oil 40 excessively stored in the recess 21a from the notch 21b 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 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 in 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 below the discharge cover 13 and above the upper bearing 21, and includes a fixed scroll 33, a turning scroll 35, a slide bush 37, and the like. It is equipped with.

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

  The orbiting scroll 35 is formed with a spiral movable side wrap 35b 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 of 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 with the phases shifted from each other, so that the compression is defined by the end plates 33a and 35a and the wraps 33b and 35b. A chamber is formed. The orbiting scroll 35 has a cylindrical boss 35c to which the eccentric pin 25 of the rotary 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 based on the eccentric rotation of the eccentric pin 25 by a rotation prevention mechanism 39 such as a well-known Oldham link arranged between the outer surface of the movable side end plate 35a and the upper bearing 21. While turning around.

  The slide bush 37 is accommodated in the concave portion 21 a of the upper bearing 21 described above, and is interposed between the eccentric pin 25 of the rotary shaft 19 and the boss 35 c of the orbiting scroll 35, and the rotational movement of the eccentric pin 25 is controlled by the orbiting scroll 35. It is transmitted as a swivel movement. The slide bush 37 is provided so as to be slidable in the radial direction of the eccentric pin 25 in order to maintain the engagement between the movable wrap 35 b of the orbiting scroll 35 and the fixed 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 through 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 inhaling indoors. Here, a part of the lubricating oil 40 discharged into the housing 3 through the oil discharge hole 21c is wound up by the low-pressure refrigerant in the low-pressure chamber 3A, so that the low-pressure refrigerant mixes with the fixed scroll 33. It is sucked between the orbiting scroll 35 and supplied to the sliding portion between the fixed scroll 33 and the orbiting scroll 35. For this reason, the lubricating oil 40 mixed in the refrigerant seals a minute gap between the wraps 33b and 35b, thereby preventing the refrigerant from leaking from the gap and suppressing a decrease in the operating 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-side end plate 33a, opens the discharge reed valve 13b of the discharge cover 13 by its own pressure, and opens from the opening hole 13a to the high-pressure chamber. 3B and discharged to the outside of the housing 3 through the discharge pipe 11.

  By the way, in recent years, in the refrigeration apparatus and the air conditioner using the scroll compressor 1, there is a tendency for improvement of the refrigeration capacity or the air conditioning capacity. In general, a scroll compressor is known in which the upper limit value of the rotational speed (operating frequency) is set to 100 to 140 rps. However, the upper limit value is increased from the conventional value (for example, 150 rps or more), and a wider rotational speed range is obtained. Driving at is being considered. When expanding the operable rotation speed range, from the viewpoint of supplying lubricating oil, first, for example, during low speed operation (low rotation speed range) of about 50 rps, the gap between the laps 33b and 35b is sealed. In order to suppress a decrease in operating efficiency, it is necessary to supply a sufficient amount of lubricating oil 40 to each sliding portion. Secondly, for example, during high speed operation (high rotation region) of 150 rps or higher, the amount of lubricating oil 40 discharged to the outside of the housing 3 together with the refrigerant increases, so that the lubrication stored in the housing 3 is increased. In order to prevent a shortage of the amount of oil 40, it is necessary to suppress the amount of lubricating oil discharged. However, in general, when the number of rotations of the motor 5 is increased to increase the supply amount of the lubricating oil 40, the amount of lubricating oil discharged to the outside of the housing 3 also increases. Therefore, the first and second conditions described above are satisfied. It was difficult to achieve both. The scroll compressor 1 according to the present embodiment achieves both suppression of reduction in operating efficiency during low speed operation and reduction in the amount of lubricating oil discharged to the outside of the housing 3 during high speed operation.

  FIG. 2 is a cross-sectional view of the oil supply pump. The oil supply pump 29 is a so-called rolling piston type (volumetric type) oil supply pump, and is provided in the lower bearing 23 as shown in FIG. The oil supply pump 29 includes a cylinder chamber 45 whose lower opening is sealed by a cover body 44 attached to the bottom surface of the lower bearing 23. The cover body 44 is integrally provided with a suction nozzle 43 extending downward, and a suction port 43 </ b> A communicating with the cylinder chamber 45 is formed in the suction nozzle 43. As shown in FIGS. 1 and 2, a rotor 47 fitted into an eccentric shaft portion 46 formed at the lower end of the rotary shaft 19 is accommodated in the cylinder chamber 45. Along with the rotation, a revolving and turning motion is made while slidingly contacting the inner peripheral surface of the cylinder chamber 45. As shown in FIG. 2, the rotor 47 is integrally provided with a blade 47A that partitions the cylinder chamber 45 into an oil supply chamber 45A and an oil discharge chamber 45B. Lubricating oil 40 accumulated in the oil reservoir 41 due to the revolving and turning motion of the rotor 47 is sucked into the oil supply chamber 45A through the suction port 43A and the oil supply port 48 of the suction nozzle 43 and discharged from the oil discharge chamber 45B to the oil discharge port 49. Then, the oil is fed to the oil supply hole 27 of the rotary shaft 19 through the communication path 50 (see FIG. 1). Since the rolling piston type oil supply pump 29 has a suction loss during high-speed rotation, the oil supply amount during high-speed operation of the motor 5 (compressor 1) can be effectively suppressed. The rolling piston type oil pump 29 described above is merely an example, and other types of oil pumps may be adopted as long as they are positive displacement oil pumps.

  As described above, the lubricating oil 40 pumped up by the oil supply 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 passes through the upper oil supply hole 27a and the lower oil supply hole 27b. Supplied to the sliding parts of the upper bearing 21 and the lower bearing 23 and the rotary shaft 19 respectively. A part of the lubricating oil 40 is stored in the concave portion 21a of the upper bearing 21 and supplied to the sliding portion between the concave portion 21a and the orbiting scroll 35, and the excess lubricating oil 40 passes through the oil drain hole 21c. The oil sump 41 is returned.

  In the present embodiment, the inner diameter D of the suction port 43A of the oil 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, the equivalent diameter d2 of the oil discharge hole 21c, and d1 ≦ D ≦ There is a relationship satisfying d2.

  Here, the minimum diameter d1 of the oil supply hole 27 refers to a portion having the narrowest inner diameter among the oil supply holes 27 to be supplied from the oil supply pump 29 to the sliding portions (the upper bearing 21, the recess 21a, and the lower bearing 23). In the present embodiment, the inner diameters of the upper oil supply hole 27a and the lower oil supply 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 cross-sectional area of the oil drain hole 21c and L is the outer length of the oil drain hole 21c. .

  According to this configuration, since the minimum diameter d1 (the inner diameters of the upper oil supply hole 27a and the lower oil supply hole 27b) in the oil supply hole 27 is equal to or smaller than the inner diameter D of the suction port 43A, the lubricating oil 40 pumped up by the oil supply pump 29 is surely obtained. The upper bearing 21 and the lower bearing 23 can be supplied to the sliding portion of the rotary shaft 19. In addition, 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 lubricating oil stored in the bottom oil reservoir 41 from being insufficient.

  The positive displacement oil pump 29 generally has a tendency to increase pressure loss as the rotational speed increases. However, since the inner diameter D of the suction port 43A of the oil pump 29 is configured to satisfy d1 ≦ D ≦ d2, Loss can be increased.

  FIG. 3 is a graph showing the relationship between the pump oil supply amount Q and the motor rotation speed with respect to the scroll displacement amount Vs. FIG. 4 is a graph showing the relationship between the amount of oil supplied per unit time of the pump and the rotational speed of the motor. The pump oil amount Q (cc / rev) is a value indicating the amount of oil supplied (discharged) per revolution by the oil pump 29, and the scroll displacement amount Vs (cc / rev) is determined by the scroll compression mechanism 7 per revolution. This is a value indicating the amount of displacement (discharge). In the present embodiment, the theoretical value of the pump oil supply amount Q / scroll push amount Vs in the oil supply pump 29 is 0.008.

  FIG. 3 shows the pump oil supply amount Q (cc / rev) of the oil supply pump 29 having the above-described performance measured with the rotational speed changed. As shown in FIG. 3, the actual measured value of the pump oil supply amount Q / the scroll displacement amount Vs tends to decrease as the rotational speed of the motor 5 increases compared to the theoretical value. Specifically, at the time of low speed operation (low rotation range) where the rotational speed of the motor 5 is 0 rps or more and 60 rps or less, Q / Vs> 0.006 is satisfied, whereas the rotational speed of the motor 5 is at least 150 rps. During high-speed operation of 200 rps or less (high rotation range), the pressure is reduced to a range satisfying 0.003 ≦ Q / Vs ≦ 0.006. In general, the OCR (ratio of the amount of discharged oil in the refrigerant circulation amount) tends to increase exponentially with respect to the rotation speed of the motor 5 (compressor). For this reason, when the rotation speed of the motor 5 is in the range of 0 rps to 60 rps, the OCR becomes small, and the magnitude of the oil supply amount of the oil pump 29 greatly affects the efficiency.

  In this configuration, the pump oil amount Q / scroll push amount Vs during low-speed operation satisfies Q / Vs> 0.006. Therefore, as shown in FIG. 4, the oil amount V per unit time during low-speed operation. The measured value of (cc / s) can keep a small deviation from the theoretical value. For this reason, the amount of lubricating oil mixed in the refrigerant can be sufficiently secured, and the lubricating oil seals a minute gap between the laps 33b and 35b, thereby preventing the refrigerant from leaking from the gap. And the fall of the operation efficiency of scroll compressor 1 can be controlled. In addition, when the pump oil amount Q / scroll displacement amount Vs during low-speed operation is Q / Vs ≦ 0.006, a sufficient amount of lubrication is sufficient to seal the minute gap between the wraps 33b and 35b. Oil cannot be supplied, leading to a reduction in operating efficiency of the scroll compressor 1.

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

  In this embodiment, the pump oil amount Q / scroll push amount Vs during high-speed operation is configured to satisfy 0.003 ≦ Q / Vs ≦ 0.006, but the range is Q / Vs <0.003. Then, since the amount of lubricating oil supplied to each sliding part is reduced, the scroll compression mechanism 7, the upper bearing 21, and the lower bearing 23 are poorly cooled, and the scroll compression mechanism 7, the upper bearing 21, and the lower bearing 23 are seized. May occur. Further, in the range of 0.006 <Q / Vs, the amount of lubricating oil discharged from the scroll compressor 1 increases as the amount of lubricating oil supplied from the oil supply pump 29 increases, and as a result, the housing 3 When the amount of lubricating oil stored in the inside is reduced, the scroll compression mechanism 7, the upper bearing 21, and the lower bearing 23 may be poorly cooled, and the scroll compression mechanism 7, the upper bearing 21, and the lower bearing 23 may be seized. is there.

  In the present embodiment, as shown in FIG. 4, in the graph of the actual measurement value of the oil supply amount V per unit time, the slope θ indicating the increase rate of the oil supply amount decreases as the rotation speed increases. . For this reason, not only can the supply amount of the lubricating oil be suppressed during high-speed operation, but also the supply amount of the lubricating oil to each sliding portion can be sufficiently ensured during low-speed operation.

  Although one embodiment of the present invention has been described above, this embodiment is presented as an example and is not intended to limit the scope of the invention. The present embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. This embodiment and its modifications are included in the scope of the present invention and the gist thereof, and are also included in the invention described in the claims and the equivalents thereof.

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 part)
21c Oil drain hole (return oil passage)
23 Lower bearing (bearing part)
27 Oil supply hole (oil supply path)
27a Upper oil supply hole (oil supply path)
27b Lower oil supply hole (oil supply path)
29 Oil supply pump (lubricating oil pump)
31 cover plate 33 fixed scroll 33a fixed side end plate 33b fixed side wrap 33c discharge hole 35 orbiting scroll 35a movable side end 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 portion 47 Rotor 47A Blade 48 Oil supply port 49 Oil discharge port 50 Communication path D Inner diameter d1 Minimum diameter d2 Equivalent diameter

Claims (4)

A housing into which low pressure gas flows,
A scroll compression mechanism that is housed in the housing and compresses the low-pressure gas;
A drive motor connected to the scroll compression mechanism by a drive shaft to drive the scroll compression mechanism;
A bearing that rotatably supports the drive shaft;
A lubricating oil pump that pumps up the lubricating oil stored in the bottom of the housing by rotation of the drive shaft and supplies it to each sliding portion of the scroll compression mechanism and the bearing portion;
The lubricating oil pump can be operated in an operation region where the rotational speed of the drive motor is at least 150 rps or more, and a slope indicating an increase rate of the amount of oil supply per unit time with respect to the rotational speed increases as the rotational speed increases. A scroll compressor characterized by being a positive displacement pump. When the lubricating oil pump has Q (cc / rev) as the pump oil supply amount per rotation of the lubricating oil pump and Vs (cc / rev) as the scroll displacement per rotation of the scroll compression mechanism,
In the operating region where the rotational speed of the drive motor is 0 rps or more and 60 rps or less,
Q / Vs> 0.006
The filling,
In an operating region where the rotational speed of the drive motor is at least 150 rps and 200 rps,
0.003 ≦ Q / Vs ≦ 0.006
The scroll compressor according to claim 1, wherein: An oil supply passage through which the lubricating oil supplied to the sliding portion flows, and a return oil passage for returning excess lubricating oil supplied to the sliding portion into the housing,
When the minimum diameter in the oil supply path is d1, the equivalent diameter of the return oil path 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, wherein the scroll compressor is satisfied.   4. The scroll compressor according to claim 1, wherein the lubricating oil pump is a rolling piston type lubricating oil pump. 5.

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