Variable-speed scroll compressor with oil flow regulating device for refrigeration

Abstract

A scroll compressor includes: a compressor housing; a compression unit comprising a fixed scroll and an orbiting scroll (11) defining a compression volume; an oil tank; a drive shaft (15) comprising a drive portion (17) coupled with the orbiting scroll (11); a variable speed electric motor configured to drive the drive shaft (15) in a rotatable manner; an oil injection system comprising an oil supply channel (26) fluidly connected to the oil sump and extending over the entire length of the drive shaft (15), and an oil injection device (27, 28) provided on the orbiting scroll (11) and configured to deliver oil from the oil supply channel (26) to the compression volume (13); and an oil flow regulating device (29) configured to regulate an oil flow from the oil supply channel (26) to the oil injection device (27, 28).

Description

Technical Field

[0001] The present invention relates to a variable speed scroll compressor for refrigeration having means for controlling the injection of oil into the compression volume. Background Art

[0002] During the operation of a scroll compressor, there are multiple pockets (also known as compression chambers) between the orbiting scroll and the fixed scroll, in which the refrigerant is compressed. The oil circulation ratio (OCR) level is very important for the scroll compressor to ensure a good seal between the pockets. If the OCR is too low, internal leakage between consecutive pockets will increase and the efficiency of the scroll compressor will be negatively affected. On the other hand, if the OCR is too high, it will lead to a decrease in the thermodynamic efficiency of the compression because there is too much oil relative to the refrigerant. Therefore, during the operation of the scroll compressor, it is necessary to ensure an appropriate OCR level.

[0003] The OCR level can be generated in a natural way (when oil droplets are dragged from the low pressure side of the scroll compressor by the refrigerant flow) or can be generated by some additional equipment (such as by an additional oil injector). In a fixed speed scroll compressor for refrigeration, the amount of OCR generated in a natural way can be calculated, and if the naturally generated OCR level is insufficient, additional oil can be delivered.

[0004] The OCR level also depends on the operating conditions: at low evaporating temperatures, the refrigerant density is low and fewer oil droplets are dragged along. Conversely, at high evaporating temperatures, the refrigerant density is high, which causes more oil droplets to be dragged along. However, this effect is minor and may affect the OCR level by only 1 or 2% at most.

[0005] JP2003286976A discloses a scroll compressor having an oil delivery hole for delivering lubricating oil to the compression stage of the scroll compressor. The amount of oil delivered can be adjusted by the hole diameter, which corresponds to the optimal lubricating oil supply. This solution provides a constant oil delivery flow and is always active.

[0006] The situation becomes complicated with variable speed scroll compressors for refrigeration. In this type of scroll compressor, the OCR level generated in a natural way varies depending on the operating speed of the scroll compressor. When the scroll compressor is operated at low speed, the speed of the refrigerant flow flowing through the scroll compressor is low, and therefore the amount of oil droplets dragged by the refrigerant flow is low. Therefore, at the low speed of the scroll compressor, additional oil delivery is required. On the other hand, when the scroll compressor is operated at high speed, the speed of the refrigerant flow flowing through the scroll compressor is high, and therefore the amount of oil droplets dragged by the refrigerant flow is high. Therefore, at the high speed of the scroll compressor, additional oil delivery is not required. Therefore, a solution with a variable oil delivery flow is needed.

[0007] FR 2 984 425 A1 discloses a scroll compressor having an oil injection device including an oil pump. This solution provides a variable oil delivery flow, but requires additional equipment and is therefore complex and expensive.

[0008] CN201443509U discloses a scroll compressor having a device for controlling oil delivery through an oil passage. The device is installed in an orbiting scroll. The amount of oil traveling through the oil passage is controlled by controlling the closing time of the oil hole. This solution is very complex and expensive. In addition, the space inside the orbiting scroll is greatly limited. In addition, since the device is located in the orbiting scroll, since the movement of the orbiting scroll is orbiting, it is exposed to sinusoidal centrifugal loads, making it difficult to develop.

[0009] Finally, FR2919688A1, which is considered to be the closest prior art to the present invention, discloses a variable speed scroll compressor for refrigeration, comprising an oil injection circuit arranged to inject oil into the compression volume, wherein the oil injection circuit comprises a movable blocking member, which is operated by centrifugal force between a first position and a second position, the first position releasing the oil injection device and enabling oil to be injected into the compression volume, and the second position blocking the oil injection device and preventing oil from being injected into the compressor volume, the blocking member being arranged to be shifted to its second position when the speed of the scroll compressor exceeds a predetermined value.

[0010] However, the moving barrier is spring pressed against the orbiting scroll and is therefore in constant sliding contact with the orbiting scroll. Therefore, this solution is subject to excessive wear. Secondly, it is difficult to maintain a proper seal between the moving barrier and the orbiting scroll throughout the life of the scroll compressor.

[0011] Furthermore, FR2919688A1 does not provide a reliable solution for ensuring that the contact surface between the orbiting scroll and the housing, which is configured to handle the axial loads from the compressed gas, is properly lubricated while ensuring the orbiting motion of the orbiting scroll. Since the opening for delivering oil to the compression stage is substantially aligned with the axis of rotation of the drive shaft, it may happen that a large part of the oil traveling through the oil supply channel provided on the drive shaft will be directly used to inject oil into the compression stage, and as a result the contact surface will be starved of oil.

[0012] Furthermore, assembling the moving stopper at the upper portion of the drive shaft requires applying a preload to a spring configured to cooperate with the moving stopper, and is therefore at least somewhat difficult. Summary of the invention

[0013] The object of the present invention is to overcome the above mentioned drawbacks of prior art solutions and to provide a simple, reliable and cheap solution to ensure a proper OCR level during operation of a variable speed scroll compressor.

[0014] According to the present invention, there is provided a scroll compressor, comprising: a compressor housing, the compressor housing being provided with a suction joint and a discharge joint, the suction joint being configured to supply refrigerant gas to be compressed to the scroll compressor, and the discharge joint being configured to discharge the compressed refrigerant gas; a compression unit installed inside the compressor housing and configured to compress the refrigerant gas supplied by the suction connection, the compression unit comprising a fixed scroll and an orbiting scroll, the orbiting scroll being configured to perform an orbiting motion relative to the fixed scroll during operation of the scroll compressor, the fixed scroll and the orbiting scroll defining a compression volume; An oil tank, the oil tank being arranged inside the compressor housing; a drive shaft disposed inside the compressor housing and including a drive portion coupled to the orbiting scroll and configured to drive the orbiting scroll to perform an orbiting motion, the drive shaft being rotatable about a rotation axis; a variable speed electric motor disposed inside the compressor housing and configured to rotatably drive the drive shaft; an oil injection system configured to inject oil into at least the compression volume, the oil injection system comprising an oil supply passage fluidly connected to the oil sump and extending over the entire length of the drive shaft, and an oil injection device disposed on the orbiting scroll and configured to deliver oil from the oil supply passage to the compression volume; and an oil flow regulating device, the oil flow regulating device being configured to regulate (ie, control) the oil flow from the oil supply passage to the oil injection device, the oil flow regulating device comprising: - a mounting body mounted at an upper end face of the drive portion, wherein the upper end face of the drive portion and the mounting body define a first volume in flow communication with the oil supply passage of the drive shaft, and the mounting body and the orbiting scroll at least partially define a second volume in flow communication with the oil injection device; an oil passage opening formed in the mounting body and through which the first volume and the second volume are configured to be in flow communication with each other; and - an oil flow regulating member, which is movable between a first position at a first speed of the variable speed electric motor and a second position at a second speed of the variable speed electric motor higher than the first speed, wherein when the oil flow regulating member is in the first position, the oil flow regulating member allows oil flow through the oil passage opening, and when the oil flow regulating member is in the second position, the oil flow regulating member restricts oil flow through the oil passage opening.

[0015] Due to the presence of the first volume and the second volume, the oil flow regulating device according to the present invention does not come into sliding contact with the orbiting scroll member, thereby improving the life and reliability of the oil flow regulating device, and thereby improving the life and reliability of the scroll compressor including such an oil flow regulating device.

[0016] Furthermore, the configuration of the oil flow regulating device according to the present invention ensures that the oil flow regulating device can be easily mounted on the drive shaft and thereby simplifies the assembly of the scroll compressor of the present invention.

[0017] Furthermore, since flow through the oil injection device is impeded at high compressor speeds, the size (diameter) of the oil injection device may be significantly increased to further improve oil injection flow at low compressor speeds.

[0018] According to an embodiment of the present invention, the mounting body includes a bottom wall and a peripheral wall extending from the bottom wall toward the driving shaft.

[0019] According to an embodiment of the present invention, the peripheral wall and the oil flow regulating member define a variable oil flow passage therebetween, ie, an oil flow passage having a variable flow cross section.

[0020] According to an embodiment of the invention, the bottom wall extends substantially perpendicularly to the rotation axis of the drive shaft.

[0021] According to an embodiment of the present invention, the upper end surface of the driving portion comprises an annular fixing groove, and the mounting body (and in particular the peripheral wall of the mounting body) is fixed in the annular fixing groove.

[0022] According to an embodiment of the invention, the oil supply channel emerges in an upper end face of the drive portion. Advantageously, the upper end face of the oil supply channel faces the bottom wall of the mounting body.

[0023] According to an embodiment of the invention, said oil supply channel emerges in said first volume.

[0024] According to an embodiment of the present invention, the fixed scroll member includes a fixed base plate and a fixed spiral scroll, and the orbiting scroll member includes an orbiting base plate and an orbiting spiral scroll, and the fixed spiral scroll and the orbiting spiral scroll are wound to form a plurality of compression chambers. Advantageously, the oil injection device is arranged on the orbiting base plate.

[0025] According to an embodiment of the invention, a first volume in fluid communication with the oil supply channel is defined by the bottom wall, the peripheral wall and the drive shaft.

[0026] According to an embodiment of the invention, a second volume in fluid communication with the oil injection device is defined by the mounting body, the orbiting scroll and the drive shaft.

[0027] According to an embodiment of the present invention, the bottom wall of the mounting body is circular.

[0028] According to an embodiment of the present invention, the peripheral wall of the mounting body has a cylindrical shape.

[0029] According to an embodiment of the invention, the oil passage opening is formed in the peripheral wall of the mounting body. Such a position of the oil passage opening limits the risk of oil flowing directly from the oil supply channel into the second volume and thereby ensures proper lubrication of the bearings of the shaft at low speeds of the variable speed electric motor.

[0030] According to an embodiment of the invention, the oil passage opening extends circumferentially on a peripheral wall of the mounting body.

[0031] According to an embodiment of the invention, the oil passage opening is elongated in the circumferential direction.The oil passage opening may have a rectangular shape.

[0032] According to an embodiment of the present invention, the oil flow regulating member is configured to block the oil flow through the oil passage opening when the oil flow regulating member is in the second position. In particular, the oil flow regulating member is configured to tightly close the oil passage opening when the oil flow regulating member is in the second position. This configuration of the oil flow regulating member ensures that no oil is injected into the compression volume at a high speed (second speed) of the scroll compressor, and thus improves efficiency.

[0033] According to an embodiment of the invention, the oil flow regulating member is configured to move from the first position to the second position under the operation of centrifugal force, ie when the centrifugal force acting on the oil flow regulating member is higher than a predetermined threshold force.

[0034] According to an embodiment of the invention, the oil flow regulating member is elastically deformable between the first position and the second position, and the oil flow regulating member is provided with a fixed first end and a free second end.

[0035] According to an embodiment of the present invention, the oil flow regulating member has a curved shape.

[0036] According to an embodiment of the invention, the oil flow regulating member has at least two separate sections with different elasticity. By having multiple sections with different elasticity, variable characteristics of the oil flow regulating member can be obtained. For example, the oil flow regulating member can be configured to: move quickly from the first position to the intermediate position (and thus quickly affect the oil flow through the oil passage opening) when the speed of the variable speed electric motor increases from the first speed to a higher intermediate speed; and move slowly from the intermediate position to the second position (and thus slowly affect the oil flow through the oil passage opening and provide smooth closing of the oil passage opening) when the speed of the variable speed electric motor increases from the intermediate speed to the second speed.

[0037] According to an embodiment of the invention, the oil flow regulating member comprises a mass member attached to the free second end.

[0038] According to an embodiment of the invention, at least when the oil flow regulating member is in the second position, the oil flow regulating member has a shape that at least partially corresponds to one of the peripheral walls. By means of such a shape of the oil flow regulating member, the oil passage opening can be tightly closed in a fluidic manner without requiring any additional sealing member.

[0039] According to an embodiment of the present invention, the scroll compressor also includes a supporting device, which includes a thrust bearing surface, the orbiting scroll member can be slidably mounted on the thrust bearing surface, and the oil injection system is configured to lubricate the thrust bearing surface with oil supplied from the oil supply channel.

[0040] According to an embodiment of the invention, the oil injection system comprises a thrust bearing lubrication channel formed in the drive shaft and in flow communication with the first volume.

[0041] According to an embodiment of the present invention, the thrust bearing lubrication channel includes an oil inlet orifice and an oil outlet orifice, wherein the oil inlet orifice appears in the upper end surface of the driving part and is connected to the first volume flow, and the oil outlet orifice appears in the outer circumferential surface of the driving part.

[0042] According to an embodiment of the invention, when the oil flow regulating member is in the first position, the oil flow regulating member extends at least partially between the oil passage opening and the upper end of the oil supply channel, as viewed from above. Thus, when the oil flow regulating member is in the first position, the oil flow regulating member forms an oil deflector for at least a portion of the oil flowing out of the oil supply channel.

[0043] According to an embodiment of the present invention, the oil passage opening and the oil inlet orifice of the thrust bearing lubrication passage are each angularly positioned relative to the rotation axis of the drive shaft, so that when the oil flow regulating member is in the first position, the oil from the oil supply passage is preferentially delivered to the thrust bearing lubrication passage rather than to the oil passage opening. In other words, the oil passage opening and the oil inlet orifice of the thrust bearing lubrication passage are each angularly positioned relative to the rotation axis of the drive shaft, so that when the oil flow regulating member is in the first position, the oil flowing out of the oil supply passage first reaches the thrust bearing lubrication passage before reaching the oil passage opening. This construction of the scroll compressor ensures a reliable and constant supply of oil, especially to the thrust bearing surface, and prevents the thrust bearing surface from being starved of oil.

[0044] According to an embodiment of the invention, the oil passage opening and the oil inlet orifice of the thrust bearing lubrication channel are angularly offset relative to the rotation axis of the drive shaft.

[0045] According to an embodiment of the invention, the oil inlet orifice is located in a first half space defined by a reference plane including a central axis of the drive portion and a rotation axis of the drive shaft, and the oil passage opening is located in a second half space defined by the reference plane.

[0046] According to an embodiment of the invention, the oil inlet aperture and the oil passage opening are substantially diametrically opposed with respect to the rotation axis of the drive shaft.

[0047] According to an embodiment of the present invention, the scroll compressor further comprises an upper counterweight connected to the driving portion and configured to at least partially balance the mass of the orbiting scroll.

[0048] According to an embodiment of the present invention, the oil injection system further comprises an oil supply passage, which is at least partially defined by the upper counterweight and is configured to supply oil from the thrust bearing lubrication channel, and the oil supply passage is configured to supply oil to the thrust bearing surface.

[0049] According to an embodiment of the invention, the orbiting scroll further comprises a cylindrical hub, in which the driving portion of the driving shaft is at least partially mounted.

[0050] According to an embodiment of the present invention, the scroll compressor further comprises a hub bearing, which is disposed in the cylindrical hub and is configured to cooperate with a driving portion of the driving shaft.

[0051] According to an embodiment of the invention, the oil flow regulating member is fixed to the mounting body, and for example to a peripheral wall of the mounting body.

[0052] According to another embodiment of the present invention, the oil flow regulating member is fixed to the drive shaft.

[0053] According to an embodiment of the invention, the oil flow regulating member is located in the mounting body, and in particular in the first volume.

[0054] According to an embodiment of the invention, the mounting body is press-fitted onto the driving portion of the driving shaft.

[0055] According to an embodiment of the invention, the scroll compressor further comprises an indexing device configured to define a single angular position of the mounting body relative to the driving portion.

[0056] According to an embodiment of the present invention, the dividing device includes a protruding member and a receiving hole, wherein the protruding member is arranged on the driving part and protrudes from the upper end surface of the driving part, and the receiving hole is arranged on the mounting body and the protruding member is received in the receiving hole.

[0057] According to an embodiment of the present invention, the accommodating hole is arranged on the bottom wall of the mounting body.

[0058] According to an embodiment of the invention, the protruding member is centered on the rotation axis of the drive shaft.

[0059] According to an embodiment of the present invention, the oil injection device comprises at least one injection channel and at least one injection nozzle, the at least one injection channel being arranged on the orbiting baseplate of the orbiting scroll member and being connected to the second volume fluid, the at least one injection nozzle being arranged on the orbiting baseplate of the orbiting scroll member and being connected to the at least one injection channel fluid, the at least one injection nozzle being present in the compression volume.

[0060] According to an embodiment of the invention, the at least one injection nozzle is present in an upper surface of the rotating substrate.

[0061] According to an embodiment of the invention, the diameter of the at least one injection nozzle is about 3 mm.

[0062] According to an embodiment of the present invention, the drive shaft includes an upper guide portion adjacent to the drive portion and a lower guide portion opposite to the upper guide portion, and the scroll compressor also includes an upper main bearing and a lower main bearing, the upper main bearing being arranged on a supporting device and being configured to guide the upper guide portion of the drive shaft to rotate, and the lower main bearing being configured to guide the lower guide portion of the drive shaft to rotate.

[0063] According to an embodiment of the present invention, the oil injection system is configured to at least partially lubricate the upper main bearing and / or the hub bearing with the oil supplied from the oil supply channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] The following detailed description of embodiments of the present invention will be better understood when read in conjunction with the accompanying drawings whereby the invention is understood not to be limited to the specific embodiments disclosed.

[0065] Figure 1 is a longitudinal sectional view of a scroll compressor according to an embodiment of the present invention.

[0066] Figure 2 yes Figure 1 A partial longitudinal cross-sectional view of a scroll compressor.

[0067] Figure 3 yes Figure 2 A magnified view of the details.

[0068] Figure 4 is along with Figure 2 A partial longitudinal sectional view of a section taken at an angle offset, Figure 1 A partial longitudinal cross-sectional view of a scroll compressor.

[0069] Figure 5 yes Figure 1 A top perspective view of an oil flow regulating device of a scroll compressor.

[0070] Figure 6 yes Figure 5 A bottom perspective view of an oil flow regulating device.

[0071] Figure 7 yes Figure 5 Bottom view of the oil flow regulating device.

[0072] Figure 8 yes Figure 1 The scroll compressor is equipped with Figure 5 Cross-sectional view of the drive shaft of the oil flow regulating device. DETAILED DESCRIPTION

[0073] Figure 1 A longitudinal sectional view of a scroll compressor 2 according to an embodiment of the present invention is shown.

[0074] The scroll compressor 2 includes a compressor housing 3 provided with a suction connection 4 configured to supply refrigerant gas to be compressed to the scroll compressor 2 and a discharge connection 5 configured to discharge the compressed refrigerant gas.

[0075] The scroll compressor further comprises a base plate 6 which is fixed to the compressor housing 3 and provides a stable support for the scroll compressor 2 .

[0076] The scroll compressor 2 further comprises a support device 7, which is arranged in the compressor housing 3 and fixed to the compressor housing 3, and a compression unit 8, which is also arranged in the compressor housing 3 and arranged above the support device 7. The compression unit 8 is configured to compress the refrigerant gas supplied by the suction connection 4, and the compression unit 8 comprises a fixed scroll 9, which is fixed relative to the compressor housing 3, and an orbiting scroll 11, which is configured to perform an orbiting movement relative to the fixed scroll 9 during operation of the scroll compressor 2. Advantageously, the orbiting scroll 11 is supported by and slidably contacts a thrust bearing surface 12 provided on the support device 7, and the fixed scroll 9 and the orbiting scroll 12 define a compression volume 13.

[0077] Specifically, the fixed scroll 9 includes a fixed base plate 9.1 having a lower surface oriented toward the orbiting scroll 11 and an upper surface opposite to the lower surface of the fixed base plate 9.1. The fixed scroll 9 also includes a fixed spiral wrap 9.2 protruding from the lower surface of the fixed base plate 9.1 toward the orbiting scroll 11.

[0078] The orbiting scroll 11 comprises an orbiting base plate 11.1 having an upper surface oriented toward the fixed scroll 9 and a lower surface opposite to the upper surface of the orbiting base plate 11.1 and slidably mounted on the thrust bearing surface 12. The orbiting scroll 11 also comprises an orbiting spiral wrap 11.2 protruding from the upper surface of the orbiting base plate 11.1 toward the fixed scroll 9. The orbiting spiral wrap 11.2 of the orbiting scroll 11 is meshed with the fixed spiral wrap 9.2 of the fixed scroll 9, thereby forming a plurality of compression chambers 14 therebetween. When the orbiting scroll 11 is driven to orbit relative to the fixed scroll 9, each compression chamber 14 has a variable volume that decreases from the outside to the inside.

[0079] The scroll compressor 2 further comprises a drive shaft 15, which is arranged inside the compressor housing 3 and is configured to drive the orbiting scroll member 11 to perform an orbiting movement, and a variable speed electric motor 16, which is arranged inside the compressor housing 3 and is coupled to the drive shaft 15. In particular, the variable speed electric motor 16 is configured to drive the drive shaft 15 to rotate around the rotation axis A. According to the embodiment shown in the drawings, the variable speed electric motor 16 is arranged below the support device 7.

[0080] The drive shaft 15 comprises at its upper end a drive portion 17 which is offset from the longitudinal axis of the drive shaft 15 (and is therefore eccentric relative to the remainder of the drive shaft 15) and which is partially mounted in a cylindrical hub 18 which is arranged on the orbiting scroll 11 and projects downwardly from the orbiting base plate 11.1. The drive portion 17 is configured to cooperate with the cylindrical hub 18 so as to drive the orbiting scroll 11 to orbit relative to the fixed scroll 9 when the variable speed electric motor 16 is operated.

[0081] The drive shaft 15 further includes an upper guide portion 19 adjacent to the drive portion 17 and a lower guide portion 21 opposite to the upper guide portion 17, and the scroll compressor 2 further includes an upper main bearing 22 and a lower main bearing 23, wherein the upper main bearing 22 is disposed on the support device 7 and is configured to guide the upper guide portion 19 of the drive shaft 15 to rotate, and the lower main bearing 23 is configured to guide the lower guide portion 21 of the drive shaft 15 to rotate. The scroll compressor 2 further includes a hub bearing 24 disposed in the cylindrical hub 18 and configured to cooperate with the drive portion 17 of the drive shaft 15.

[0082] The scroll compressor 2 further includes an oil sump 25 which is arranged inside the compressor housing 3 and is configured to store oil. The oil sump 25 may be at least partially defined by a bottom portion of the compressor housing 3, for example.

[0083] Furthermore, the scroll compressor 2 comprises an oil injection system which is configured to inject oil at least into the compression volume 13 .

[0084] The oil injection system comprises in particular an oil supply channel 26 which is fluidically connected to the oil sump 25 and which extends over the entire length of the drive shaft 15. Advantageously, the oil supply channel 26 has an upper end which emerges in an upper end face 17.1 of the drive part 17 oriented towards the orbiting scroll 11. The oil supply channel 26 is inclined with respect to the longitudinal axis of the drive shaft 15 and is in particular configured to supply oil from the oil sump 25 to the upper part of the scroll compressor 2.

[0085] The oil injection system further comprises an oil injection device which is arranged on the orbiting scroll 11 , and in particular on the orbiting base plate 11 . 1 , and is configured to deliver oil from the oil supply channel 26 to the compression volume 13 .

[0086] According to the embodiment shown in the drawings, the oil injection device comprises a number of injection channels 27, which are arranged on the revolving base plate 11.1 and each of which is configured to be fluidically connected to the oil supply channel 26, and a number of injection nozzles 28, which are arranged on the revolving base plate 11.1 and each of which is in fluid communication with a respective injection channel 27. Advantageously, each injection channel 27 is rectilinear and each injection nozzle 28 emerges in the compression volume 13 and in particular in the upper face of the revolving base plate 11.1.

[0087] Furthermore, the scroll compressor 2 includes an oil flow regulating device 29 configured to regulate the flow of oil from the oil supply passage 26 to the oil injection device.

[0088] like Figure 3 As best shown, the oil flow regulating device 29 comprises a mounting body 31 which is mounted at the upper end face 17.1 of the drive part 17 and is, for example, press-fitted on the drive part 17 of the drive shaft 15. According to the embodiment shown in the figures, the mounting body 31 comprises a bottom wall 32 which is circular and extends perpendicularly to the axis of rotation A of the drive shaft 15 and a peripheral wall 33 which has a cylindrical shape and extends from the bottom wall 32 towards the drive shaft 15. The upper end face 17.1 of the drive part 17 can, for example, comprise an annular fixing groove in which the peripheral wall 33 of the mounting body 31 is fixed. Advantageously, the upper end of the oil supply channel 26 faces the bottom wall 32 of the mounting body 31.

[0089] The upper end face 17.1 of the drive portion 17 and the mounting body 31 define a first volume 34 in flow communication with the oil supply channel 26 of the drive shaft 15, and the mounting body 31 and the orbiting scroll 11 at least partially define a second volume 35 in flow communication with the oil injection device. According to the embodiment shown in the figures, the first volume 34 is defined by the bottom wall 32, the peripheral wall 33 and the upper end face 17.1 of the drive shaft 15, and the second volume 35 is defined by the mounting body 31, the orbiting scroll 11 and the drive shaft 15. In particular, the oil supply channel 26 appears in the first volume 34, and each injection channel 27 appears in the second volume 35.

[0090] The oil flow regulating device 29 further comprises an oil passage opening 36 which is formed in the mounting body 31 and through which the first volume 34 and the second volume 35 are configured to be in flow communication with each other. According to the embodiment shown in the figures, the oil passage opening 36 is formed in the peripheral wall 33 of the mounting body 31 and is axially offset with respect to the upper end face 17.1 of the drive shaft 15. Advantageously, the oil passage opening 36 is oblong in the circumferential direction and has, for example, a rectangular shape.

[0091] The oil flow regulating device 29 further includes an oil flow regulating member 37 which can be in a first position (eg, Figure 6 The oil flow regulating member 37 is configured to move between a first position (shown in the figure) and a second position (not shown in the figure) at a second speed higher than the first speed of the variable speed electric motor 16. Advantageously, when the oil flow regulating member 37 is in the first position, the oil flow regulating member 37 allows oil to flow through the oil passage opening 36, and when the oil flow regulating member 37 is in the second position, the oil flow regulating member 37 blocks oil from flowing through the oil passage opening 36. In particular, the oil flow regulating member 37 is configured to tightly close the oil passage opening 36 when the oil flow regulating member 37 is in the second position.

[0092] like Figure 7 As shown, when the oil flow regulating member 37 is in the first position, the oil flow regulating member 37 extends at least partially between the oil passage opening 36 and the upper end of the oil supply passage 26 as viewed from above.

[0093] According to the embodiment shown in the drawings, the oil flow regulating member 37 has a curved shape and is provided with a fixed first end 37.1 and a free second end 37.2. The oil flow regulating member 37 can be located, for example, in the first volume 34, and in particular in the mounting body 31, and the fixed first end 37.1 of the oil flow regulating member 37 can be fixed, for example, to the peripheral wall 33 of the mounting body 31.

[0094] Advantageously, the oil flow regulating member 37 is elastically deformable between a first position and a second position, and is configured to move from the first position to the second position under the operation of centrifugal force (i.e., when the centrifugal force acting on the oil flow regulating member 37 is higher than a predetermined threshold force). Advantageously, at least when the oil flow regulating member 37 is in the second position, the oil flow regulating member 37 has a shape that at least partially corresponds to one of the peripheral walls 33. By such a shape of the oil flow regulating member 37, when the oil flow regulating member 37 is in the second position, the oil passage opening 36 can be tightly closed in a fluid manner without requiring any additional sealing member.

[0095] The oil flow regulating member 37 may include a first section 37a, a second section 37b and a third section 37c that are longitudinally deviated from each other and have different elasticities, so that each of the first, second and third sections 37a to 37c is deformed by different speeds / levels under the operation of centrifugal force. For example, the first section 37a has the lowest elasticity, the second section 37b has a medium elasticity, and the third section 37c has the highest elasticity. In this case, during the operation of the scroll compressor 2, first the third section 37c will begin to deform, then the second section 37b begins to deform, and finally the first section 37a begins to deform. Therefore, a variable oil flow channel 38 can be obtained between the peripheral wall 33 and the oil flow regulating member 37, and the oil flow control through the oil passage opening 36 is further improved.

[0096] like Figure 3 and Figure 4 As best shown, the scroll compressor 2 further comprises an indexing device configured to define a single angular position of the mounting body 31 relative to the drive portion 17. According to the embodiment shown in the figures, the indexing device comprises a protruding member 39, which is provided on the drive portion 17 and protrudes from the upper end face 17.1 of the drive portion 17, and a receiving hole 41, which is provided on the bottom wall 32 of the mounting body 31 and in which the protruding member 39 is received. Advantageously, the receiving hole 41 is laterally offset relative to the central axis of the bottom wall 32, and the protruding member 39 is laterally offset relative to the central axis B of the drive portion 17, and the protruding member 39 can be centered, for example, on the rotation axis A of the drive shaft 15.

[0097] Advantageously, the oil injection system is also configured to lubricate the thrust bearing surface 12 with oil supplied from the oil supply passage 26 .

[0098] like Figure 4 and Figure 8As best shown, the oil injection system comprises a thrust bearing lubrication channel 42, which is formed in the drive shaft 15 and is in flow communication with the first volume 34. According to the embodiment shown in the figures, the thrust bearing lubrication channel 42 comprises an oil inlet orifice 42.1, which appears in the upper end face 17.1 of the drive part 17 and is in flow communication with the first volume 34, and an oil outlet orifice 42.2, which appears in the outer circumferential surface of the drive part 17.

[0099] The oil injection system also includes an oil supply passage 43 (see Figure 1 ), the oil supply passage 43 is at least partially defined by an upper counterweight 44 and is configured to supply oil from an oil outlet opening 42.2 of a thrust bearing lubrication passage 42, the upper counterweight 44 being connected to the drive portion 17 and configured to at least partially balance the mass of the orbiting scroll 11. In particular, the oil supply passage 43 is configured to supply oil from the thrust bearing lubrication passage 42 to the thrust bearing surface 12.

[0100] Thrust bearing lubrication passage 42 and oil supply passage 43 are configured so that a portion of the oil inside first volume 34 can flow toward the inner diameter of the upper counterweight due to centrifugal load and then spray out toward thrust bearing surface 12 at the top of the upper counterweight.

[0101] Advantageously, the oil passage opening 36 and the oil inlet orifice 42.1 of the thrust bearing lubrication passage 42 are angularly offset relative to the rotation axis A of the drive shaft 15 and are angularly positioned relative to the rotation axis A of the drive shaft 15, so that when the oil flow regulating member 37 is in the first position, oil from the oil supply passage 26 is preferentially delivered to the thrust bearing lubrication passage 42 rather than being delivered to the oil passage opening 36. In other words, the oil passage opening 36 and the oil inlet orifice 42.1 of the thrust bearing lubrication passage 42 are angularly positioned relative to the rotation axis A of the drive shaft 15, so that when the oil flow regulating member 37 is in the first position, oil flowing out of the oil supply passage 26 first reaches the thrust bearing lubrication passage 42 before reaching the oil passage opening 36. This configuration of the scroll compressor 2 ensures a reliable and constant supply of oil, in particular to the thrust bearing surface 12, and prevents the thrust bearing surface 12 from being starved of oil.

[0102] According to the embodiment shown in the drawings, the oil inlet orifice 42.1 is located in a first half space defined by a reference plane P including the central axis B of the drive part 17 and the rotation axis A of the drive shaft 15, and the oil passage opening 36 is located in a second half space defined by the reference plane P. For example, the oil inlet orifice 42.1 and the oil passage opening 36 may be substantially diametrically opposed relative to the rotation axis A of the drive shaft 15.

[0103] During operation of the scroll compressor 2, oil is delivered from the oil groove 25 to the first volume 34 through the oil supply channel 26 in the drive shaft 15. The oil is dispersed in the first volume 34 in a circle centered on the rotation axis A of the drive shaft 15. At a first speed (low speed) of the variable speed electric motor 16 (i.e., when a small amount of oil reaches the first volume 34), the radius R1 of the oil-free surface circle is greater than the radius R2 of the oil-free surface circle at a second speed (high speed) of the variable speed electric motor 16 (i.e., when a sufficient amount of oil reaches the first volume 34). This is associated with the oil parabola inside the drive shaft 15. Advantageously, the angular position of the oil passage opening 36 is defined so that, when the scroll compressor 2 is operated at the first speed (or a low oil flow through the oil supply channel 26), oil is preferentially supplied to the thrust bearing lubrication channel 42 rather than the oil passage opening 36, and proper lubrication of the shaft bearings is ensured. Oil can flow through the oil passage opening 36 only when there is enough additional oil flowing out of the oil supply channel 26.

[0104] The oil travelling through the oil passage opening 36 then enters the second volume 35 and is injected into the compression volume 13 via the injection channel 27 and the injection nozzle 28 and in particular ensures proper lubrication of the compression unit 8 .

[0105] At the second speed (high speed) of the variable speed electric motor 16, the oil flow regulating member 37 is displaced to the second position under the operation of centrifugal force and tightly closes the oil passage opening 36, so that the oil entering the first volume 34 can only leave the first volume 34 by flowing into the thrust bearing lubrication channel 42 (and not reach the second volume 35, and thus not reach the oil injection device).

[0106] Advantageously, the oil injection system is also configured to at least partially lubricate the upper main bearing 22 and / or the hub bearing 24 with oil supplied from an oil supply channel 26 , in particular through radial holes provided on the drive shaft 15 and emerging in the oil supply channel 26 .

[0107] According to an embodiment of the invention not shown in the drawings, the oil flow regulating member 37 may include a mass member attached at its free second end 37 . 2 and / or the oil flow regulating member 37 may be fixed to the drive shaft 15 .

[0108] Of course, the invention is not limited to the embodiments described above by way of non-limiting examples, but rather the invention encompasses all its embodiments.

Claims

1. A scroll compressor (2), comprising: A compressor housing (3), the compressor housing (3) being provided with a suction joint (4) and a discharge joint (5), the suction joint (4) being configured to supply refrigerant gas to be compressed to the scroll compressor (2), and the discharge joint (5) being configured to discharge the compressed refrigerant gas; a compression unit (8) mounted inside the compressor housing (3) and configured to compress the refrigerant gas supplied by the suction connection (4), the compression unit (8) comprising a fixed scroll (9) and an orbiting scroll (11), the orbiting scroll (11) being configured to perform an orbiting motion relative to the fixed scroll (9) during operation of the scroll compressor (2), the fixed scroll (9) and the orbiting scroll (11) defining a compression volume (13); An oil groove (25), the oil groove (25) being arranged inside the compressor housing (3); a drive shaft (15), the drive shaft (15) being arranged inside the compressor housing (3) and comprising a drive portion (17), the drive portion (17) being coupled to the orbiting scroll member (11) and being configured to drive the orbiting scroll member (11) to perform an orbiting motion, the drive shaft (15) being rotatable about a rotation axis (A); a variable speed electric motor (16) disposed inside the compressor housing (3) and configured to rotatably drive the drive shaft (15); an oil injection system configured to inject oil into at least the compression volume (13), the oil injection system comprising an oil supply passage (26) fluidly connected to the oil sump (25) and extending over the entire length of the drive shaft (15), and an oil injection device disposed on the orbiting scroll (11) and configured to deliver oil from the oil supply passage (26) to the compression volume (13); and An oil flow regulating device (29), the oil flow regulating device (29) being configured to regulate the oil flow from the oil supply passage (26) to the oil injection device, the oil flow regulating device (29) comprising: - a mounting body (31) mounted at an upper end face (17.1) of the drive part (17), wherein the upper end face (17.1) of the drive part (17) and the mounting body (31) define a first volume (34) in flow communication with the oil supply channel (26) of the drive shaft (15), and the mounting body (31) and the orbiting scroll (11) at least partially define a second volume (35) in flow communication with the oil injection device; an oil passage opening (36) formed in the mounting body (31) and through which the first volume (34) and the second volume (35) are configured to be in flow communication with each other; and - an oil flow regulating member (37) movable between a first position at a first speed of the variable speed electric motor (16) and a second position at a second speed of the variable speed electric motor (16) higher than the first speed, wherein when the oil flow regulating member (37) is in the first position, the oil flow regulating member (37) allows oil flow through the oil passage opening (36), and when the oil flow regulating member (37) is in the second position, the oil flow regulating member (37) restricts oil flow through the oil passage opening (36).

2. The scroll compressor (2) according to claim 1, wherein: The mounting body (31) comprises a bottom wall (32) and a peripheral wall (33) extending from the bottom wall (32) toward the drive shaft (15).

3. The scroll compressor (2) according to claim 2, wherein: The oil passage opening (36) is formed in the peripheral wall (33) of the mounting body (31).

4. The scroll compressor (2) according to claim 2 or 3, wherein: The peripheral wall (33) and the oil flow regulating member (37) define a variable oil flow passage (38) therebetween.

5. The scroll compressor (2) according to any one of claims 1 to 4, wherein: The oil flow regulating member (37) is configured to prevent oil from flowing through the oil passage opening (36) when the oil flow regulating member (37) is in the second position.

6. The scroll compressor (2) according to any one of claims 1 to 5, wherein: The oil flow regulating member (37) is configured to move from the first position to the second position under the operation of centrifugal force.

7. The scroll compressor (2) according to any one of claims 1 to 6, wherein: The oil flow regulating member (37) is elastically deformable between the first position and the second position, and is provided with a fixed first end (37.1) and a free second end (37.2).

8. The scroll compressor (2) according to claim 7, wherein: The oil flow regulating member (37) has a curved shape.

9. The scroll compressor (2) according to claim 7 or 8, wherein: The oil flow regulating member (37) has at least two separate sections with different elasticities.

10. The scroll compressor (2) according to any one of claims 1 to 9, wherein: At least when the oil flow regulating member (37) is in the second position, the oil flow regulating member (37) has a shape that at least partially corresponds to one of the peripheral walls (33).

11. A scroll compressor (2) according to any one of claims 1 to 10, further comprising a support device (7), the support device (7) comprising a thrust bearing surface (12), the orbiting scroll member (11) being slidably mounted on the thrust bearing surface (12), the oil injection system being configured to lubricate the thrust bearing surface (12) with oil supplied from the oil supply channel (26).

12. The scroll compressor (2) according to claim 11, wherein: The oil injection system includes a thrust bearing lubrication passage (42) formed in the drive shaft (15) and in flow communication with the first volume (34).

13. The scroll compressor (2) according to claim 12, wherein: The thrust bearing lubrication channel (42) comprises an oil inlet orifice (42.1) which appears in the upper end surface (17.1) of the drive part (17) and is in flow communication with the first volume (34), and an oil outlet orifice (42.2) which appears in the outer circumferential surface of the drive part (17).

14. The scroll compressor (2) according to claim 13, wherein: The oil passage opening (36) and the oil inlet orifice (42.1) of the thrust bearing lubrication passage (42) are each positioned at an angle relative to the rotation axis (A) of the drive shaft (15) so that when the oil flow regulating member (37) is in the first position, oil from the oil supply passage (26) is preferentially delivered to the thrust bearing lubrication passage (42) rather than to the oil passage opening (36).

15. The scroll compressor (2) according to any one of claims 1 to 14, wherein: The oil flow regulating member (37) is fixed to the mounting body (31).

16. The scroll compressor (2) according to any one of claims 1 to 15, further comprising indexing means configured to define a single angular position of the mounting body (31) relative to the drive portion (17).

17. The scroll compressor (2) according to claim 16, wherein: The indexing device comprises a protruding member (39) and a receiving hole, wherein the protruding member (39) is arranged on the driving part (17) and protrudes from the upper end surface (17.1) of the driving part (17); the receiving hole is arranged on the mounting body (31), and the protruding member (39) is received in the receiving hole.

18. The scroll compressor (2) according to any one of claims 1 to 17, wherein: The oil injection device comprises at least one injection channel (27) and at least one injection nozzle (28), wherein the at least one injection channel (27) is arranged on the orbiting base plate (11.1) of the orbiting scroll (11) and is in fluid communication with the second volume (35), and the at least one injection nozzle (28) is arranged on the orbiting base plate (11.1) of the orbiting scroll (11) and is in fluid communication with the at least one injection channel (27), wherein the at least one injection nozzle (28) is present in the compression volume (13).

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