CN102748295A - Rotary compressor and rotary machine - Google Patents

Abstract

The invention relates to a rotary compressor, comprising: a casing (12), which includes a lubricating oil storage part for containing lubricating oil; a compression mechanism (20) arranged in the casing (12); a drive compression mechanism ( 20) the driving mechanism (30), the driving mechanism (30) includes a rotating shaft (50), and the through holes (54, 56) extending along the axial direction of the rotating shaft (50) are arranged in the rotating shaft (50), and the rotating shaft (50) in fluid communication with the lubricating oil reservoir through the through holes (54, 56); and an oil level sensor (120) in fluid communication with the through holes (54, 56) in the rotating shaft (50) through the pressure acquisition passage (110) ). The invention also relates to a rotating machine. The invention can accurately and reliably detect the lubricating oil in the compressor in a simple manner, thus greatly saving the cost and improving the reliability of the compressor.

Description

Rotary compressors and rotating machinery

technical field

The present invention relates to a rotary compressor and a rotary machine.

Background technique

A rotary compressor generally includes a housing, a compression mechanism accommodated in the housing, a driving mechanism for driving the compression mechanism, and the like. In order to ensure the normal operation of the compressor, there must be enough lubricating oil in the compressor. The lubricating oil level in the compressor must be above the minimum protective lubricating oil level. When the lubricating oil level in the compressor is lower than the minimum protective lubricating oil level, the compressor should be stopped.

Duplex or even multi-compressor systems have been widely used. In this dual or multi-compressor system, one or more of the compressors can be selectively started and the others can be shut down, so the lubricating oil will move in these compressors and may cause The lubricating oil is unbalanced, and some compressors even lack lubricating oil.

In addition, no matter in the compressor system composed of a single compressor or in the multi-compressor system composed of multiple compressors, there may be a lack of lubricating oil due to oil leakage of the compressor system or the compressor.

In addition, in a large-scale refrigeration system, due to the long pipeline length and many components, the lubricating oil may not be circulated back to the compressor in time, causing the compressor to lack lubricating oil.

Therefore, it is necessary to accurately detect the lubricating oil state of the compressor (such as the oil level), so as to stop the compressor in time and prevent the compressor from being damaged.

Contents of the invention

The technical problem to be solved in the present invention

However, most current compressors do not have built-in oil level sensors.

Although there are some liquid level sensors that detect the liquid level, these liquid level sensors are only suitable for detecting the liquid level in the tank or container. These sensors include: piezoelectric liquid level sensors, reed switch liquid level sensors, ultrasonic liquid level sensors, photoelectric liquid level sensors, etc. The above sensors generally cannot be used in hermetic compressors, because the working environment in hermetic compressors is more severe, for example, the temperature range and pressure range in the compressor are very wide, and the pressure and temperature will cycle, and it is also possible There are impurities in castings, etc. In addition, oil foam may be generated in the compressor, so these sensors cannot accurately detect the oil level.

Therefore, there is a need for a rotary compressor capable of relatively simple and reliable detection of lubricating oil in the compressor.

Technical solutions

An object of one or more embodiments of the present invention is to provide a rotary compressor capable of simply and reliably detecting lubricating oil in the compressor.

An object of one or more embodiments of the present invention is to provide a rotary machine capable of simply and reliably detecting lubricating oil in the rotary machine.

One aspect of the present specification provides a rotary compressor including: a casing including a lubricating oil storage portion for containing lubricating oil; a compression mechanism provided in the casing; and a compressor that drives the compression mechanism. A driving mechanism, the driving mechanism includes a rotating shaft, the rotating shaft is provided with a through hole extending in the axial direction of the rotating shaft, and the rotating shaft is in fluid communication with the lubricating oil storage part through the through hole and an oil level sensor in fluid communication with the through hole in the rotating shaft through the pressure acquisition channel.

Preferably, the rotary compressor further includes a lower bearing housing for supporting the rotary shaft, wherein the pressure collection channel includes: extending through a side wall of the rotary shaft and communicating with a channel in the rotary shaft A pressure collection hole in fluid communication with the hole, a circumferential oil groove formed on the rotating shaft or the lower bearing seat and in fluid communication with the pressure collection hole, extending through the lower bearing seat and connected to the circumferential oil groove A communication channel in fluid communication with the oil level sensor.

Preferably, the rotary compressor further includes a pressure collector disposed between the rotating shaft and the oil level sensor, wherein the pressure collecting channel includes: a side wall extending through the rotating shaft and connected to the a pressure collection hole in fluid communication with a through hole in the rotation shaft, a circumferential oil groove formed on the rotation shaft or the pressure collection device and in fluid communication with the pressure collection hole, extending through the pressure collection device And a communication channel in fluid communication with the circumferential oil groove and the oil level sensor.

Preferably, the pressure collection channel further includes a pressure collection tube disposed in the pressure collection hole and protruding toward the axis of the through hole of the rotating shaft.

Preferably, the length of the pressure collection pipe is determined according to the lowest protection lubricating oil level in the lubricating oil storage part.

Preferably, the higher the minimum protection lubricating oil level is set, the longer the length of the pressure collection pipe is set.

其中，H为从所述旋转轴的端面算起的所述最低保护润滑油油位的高度，单位为毫米；L为所述压力采集管突出到所述旋转轴中的长度，单位为毫米；R为所述旋转轴的内半径，单位为毫米；h为从所述旋转轴的端面算起的所述压力采集管的中心轴线的高度，单位为毫米；n为所述旋转轴的转数，单位为转/分；g为重力加速度，单位为米/秒²。Preferably, the minimum protection lubricating oil level and the length of the pressure collection pipe satisfy the following relationship:

Wherein, H is the height of the minimum protective lubricating oil level calculated from the end face of the rotating shaft, in millimeters; L is the length of the pressure collection tube protruding into the rotating shaft, in millimeters; R is the inner radius of the rotating shaft, in millimeters; h is the height of the central axis of the pressure collection tube from the end face of the rotating shaft, in millimeters; n is the number of revolutions of the rotating shaft , the unit is rev/min; g is the acceleration due to gravity, the unit is m/ ^s2 .

Preferably, the height of the pressure collection hole from a specific reference surface (S) is determined according to the lowest protective lubricating oil level in the lubricating oil storage part.

Preferably, the higher the minimum protection lubricating oil level is set, the higher the height of the pressure collection hole is set.

Preferably, the reference surface is the bottom surface of the rotary compressor or the end surface of the rotary shaft.

Preferably, the rotary compressor further includes an oil pumping mechanism, and the oil pumping mechanism includes an orifice plate arranged at the end of the rotating shaft and an oil fork arranged in the through hole of the rotating shaft.

Preferably, the oil pumping mechanism includes a vane pump arranged at the end of the rotating shaft.

Preferably, the rotary compressor is a horizontal rotary compressor and its internal space is divided into a high-pressure side and a low-pressure side by a sound-absorbing plate, the high-pressure side constitutes the lubricating oil storage part, and the oil pumping mechanism is from The lubricating oil reservoir extends to an oil pipe of the through hole of the rotary shaft.

Preferably, the through hole includes a concentric hole portion concentric with the rotation axis and an eccentric hole portion radially offset with respect to the concentric hole.

Preferably, the oil level sensor is a pressure sensor.

Preferably, the oil level sensor is a pressure switch.

Preferably, the oil level sensor includes: a fluid pressure receiving part for receiving fluid pressure; and a conversion part capable of converting the fluid pressure into an electric signal.

Preferably, the fluid pressure receiving part includes: a casing and a piston head capable of axially moving inside the casing; the conversion part includes a terminal, a first contact and a second contact arranged in the terminal point, a spring that provides electrical communication between the piston head and the second contact and provides a restoring force to the piston head, wherein when the piston head is in contact with the first contact, the oil The bit sensor outputs an electrical signal.

Preferably, the first contact includes a plurality of needles spaced apart from each other.

Preferably, said second contact comprises an annular contact piece in electrical contact with said spring.

Preferably, the rotary compressor further includes an oil temperature sensor.

Preferably, the oil temperature sensor and the oil level sensor have a common pin.

Preferably, the oil level sensor is arranged near the lower bearing seat.

Preferably, the oil level sensor is directly connected to the communication channel in the lower bearing seat or the pressure collector.

Preferably, the oil level sensor is connected to the communication channel in the lower bearing seat or the pressure collector through an additional pipeline.

Preferably, the rotary compressor is a scroll compressor, or a screw compressor, or a rotary compressor.

Preferably, the oil level sensor is arranged inside or outside the housing.

Preferably, when the oil level sensor is arranged outside the housing, the pressure collection passage further includes a connecting pipe in fluid communication with the communication passage in the lower bearing housing or the pressure collector.

Preferably, the connecting pipe is arranged horizontally or inclined.

Another aspect of the present specification provides a rotary machine, including: a casing, the casing includes a lubricating oil storage portion for containing lubricating oil; a rotating shaft arranged in the casing, the rotating shaft A through hole extending in the axial direction of the rotating shaft is provided, the rotating shaft is in fluid communication with the lubricating oil storage part through the through hole; and the through hole in the rotating shaft is in fluid communication through a pressure collection channel oil level sensor.

Preferably, said rotating machine further comprises a bearing housing for supporting said rotating shaft, wherein said pressure collection channel comprises: extending through a side wall of said rotating shaft and in fluid communication with a through hole in said rotating shaft A pressure collection hole, a circumferential oil groove formed on the rotating shaft or the bearing seat and in fluid communication with the pressure collection hole, extending through the bearing seat and connected to the circumferential oil groove and the oil level A communication channel through which the sensor is in fluid communication.

Preferably, the rotating machine further includes a pressure collector disposed between the rotating shaft and the oil level sensor, wherein the pressure collecting channel includes: a side wall extending through the rotating shaft and connected to the a pressure pick-up hole in fluid communication with a through hole in the rotating shaft, a circumferential oil groove formed on the rotating shaft or the pressure pick-up and in fluid communication with the pressure pick-up hole, extending through the pressure pick-up and in communication with the pressure pick-up hole The communication channel through which the circumferential oil groove is in fluid communication with the oil level sensor.

Beneficial effect

The advantages of the rotary compressor and the rotary machine according to one or several embodiments of the present invention are:

An oil level detection mechanism is installed inside the compressor or rotating machinery, so it can detect the lubricating oil in the compressor or rotating machinery more timely, accurately and reliably, so as to prevent or reduce the damage of the compressor or rotating machinery due to insufficient lubricating oil.

The oil level detection mechanism includes an oil level sensor and a pressure acquisition channel in fluid communication with the through hole in the rotating shaft, and the oil level sensor can be a pressure sensor or a pressure switch. Therefore, the structure of the oil level detection mechanism is relatively simple, so that it is easy to manufacture and reduces the cost of the compressor or the rotating machine.

In one or more embodiments of the present invention, by converting the oil level detection in the compressor or the rotary machine into hydraulic detection, it is possible to detect the lubricating oil in the compressor or the rotary machine more simply and reliably, and the structural Simpler and lower cost pressure sensor or pressure switch to replace expensive liquid level sensor.

By controlling the length of the pressure collection tube or the height of the pressure collection hole, it is relatively easy to adjust the desired detection lubricating oil level. Therefore, it can be easily applied to compressors or rotary machines of various types and models.

The oil level sensor in one or more embodiments of the present invention has a simpler structure, thus lower cost, but higher reliability and shorter response time.

The first contact of the oil level sensor includes a plurality of needles spaced apart from each other, as long as any one of the needles is in contact with the piston head, a conduction signal can be output. Therefore, the reliability of the oil level sensor is improved.

The oil level sensor can be arranged inside or outside the shell of the compressor, and the oil level sensor can be connected directly with the pressure acquisition channel or through an additional pipeline, so the arrangement of various components in the compressor is greatly facilitated.

In the rotary compressor of one or more embodiments of the present invention, not only an oil level sensor but also an oil temperature sensor is provided, so multiple protections can be provided for the compressor.

Description of drawings

The features and advantages of one or several embodiments of the present invention will become more readily understood from the following description with reference to the accompanying drawings, in which:

1 is a schematic cross-sectional view of a rotary compressor according to an embodiment of the present invention;

Fig. 2 is an enlarged view of the lower part of the rotary compressor shown in Fig. 1;

3 is a schematic diagram of an oil level detection mechanism according to an embodiment of the present invention;

4 is a perspective view of a lower bearing integrated with an oil level sensor according to an embodiment of the present invention;

5 is an oil fork provided in a rotary compressor according to an embodiment of the present invention;

Fig. 6 is a front view of an oil level sensor according to an embodiment of the present invention;

7 is a cross-sectional view of an oil level sensor according to an embodiment of the present invention, showing that the oil level sensor is in a disconnected state;

8 is a cross-sectional view of an oil level sensor according to an embodiment of the present invention, showing that the oil level sensor is in a conduction state;

Fig. 9 is a schematic diagram of an oil level detection mechanism according to another embodiment of the present invention;

Fig. 10 is a schematic diagram of deformation of an oil level detection mechanism according to another embodiment of the present invention;

Figure 11 shows the relationship between the minimum protection lubricating oil level, the inner radius of the rotating shaft, the height of the pressure collection pipe and the length of the pressure collection pipe;

12 is a schematic diagram of an oil level detection mechanism according to another embodiment of the present invention; and

13A and 13B are schematic sectional views of a lower portion of a rotary compressor according to a further embodiment of the present invention.

Detailed ways

The following description of preferred embodiments is exemplary only and in no way restricts the invention and its application or usage.

A basic configuration of a rotary compressor according to the present invention will be described below with reference to FIG. 1 . FIG. 1 is a schematic sectional view of a rotary compressor according to an embodiment of the present invention. The rotary compressor shown in Figure 1 is a scroll compressor, but those skilled in the art should understand that the present invention is not limited to the scroll compressor shown in the figure, on the contrary the present invention can also be applied to other types Compressors including a rotating shaft, such as screw compressors, rotary compressors, etc., and any type of rotating machinery including a rotating shaft. In addition, the present invention is applicable not only to vertical compressors whose rotary shafts are vertically oriented, but also to horizontal compressors whose rotary shafts are horizontally oriented.

The rotary compressor 10 includes a generally cylindrical housing 12 . An air intake joint 13 is provided on the housing 12 for sucking low-pressure gaseous refrigerant. One end of the housing 12 is fixedly connected with an end cover 14 . The end cover 14 is equipped with a discharge joint 15 for discharging compressed refrigerant. Between the casing 12 and the end cover 14, there is also provided a sound-absorbing plate 16 extending transversely (in FIG. into high-pressure side and low-pressure side. The space between the end cover 14 and the muffler plate 16 constitutes a high-pressure side space, while the space between the muffler plate 16 and the casing 12 constitutes a low-pressure side space. A part of the housing 12 constitutes a lubricating oil storage portion for accommodating lubricating oil. In the example of FIG. 1 , the lubricating oil reservoir is located in the lower portion of the housing 12 .

The housing 12 accommodates a compression mechanism 20 and a drive mechanism 30 . In the example shown in FIG. 1 , the compression mechanism 20 includes a fixed scroll member 22 and an orbiting scroll member 24 that mesh with each other. The drive mechanism 30 includes a motor 40 and a rotating shaft 50 . Motor 40 includes a stator 42 and a rotor 44 . The stator 42 is fixedly connected to the housing 12 . The rotor 44 is fixedly connected to the rotary shaft 50 and rotates in the stator 42 . A first end (upper end in FIG. 1 ) of the rotary shaft 50 is provided with an eccentric crank pin 52 and a second end (lower end in FIG. 1 ) of the rotary shaft 50 may include a concentric hole 54 . The concentric bore 54 leads to the eccentric crank pin 52 at the first end of the rotary shaft 50 via an eccentric bore 56 radially offset with respect to the concentric bore 54 . The rotating shaft 50 is in fluid communication with the lubricating oil reservoir through a concentric bore 54 .

The first end of the rotary shaft 50 is supported by the main bearing housing 60 , and the second end is supported by the lower bearing housing 70 . The main bearing housing 60 and the lower bearing housing 70 are fixedly connected to the housing 12 by suitable means. The eccentric crank pin 52 of the rotary shaft 50 is inserted into the hub portion 26 of the movable scroll member 24 via a bush 58 to rotationally drive the movable scroll member 24 .

An oil pumping mechanism 80 may also be provided at the second end (lower end in FIG. 1 ) of the rotating shaft 50 . In the example shown in FIG. 1 , the oil pumping mechanism 80 includes an orifice plate 82 disposed at the second end of the rotating shaft 50 and an oil fork 84 disposed in the concentric hole 54 and rotating together with the rotating shaft 50 . The orifice plate 82 is roughly disc-shaped and has a through hole 83 at the center. An example of an oil fork 84 is shown in FIG. 5 . As shown in FIG. 5 , the oil fork 84 includes a base 86 having a generally rectangular base, and legs 87 and 88 extending from the base 86 in the same direction and diverging. The plane in which the legs 87 and 88 lie is inclined in the direction of rotation A of the rotation axis 50 with respect to the plane in which the base is situated.

When the compressor is running, lubricating oil in the lower part of the housing 12 enters the concentric hole 54 of the rotating shaft 50 through the through hole 83 of the orifice plate 82 . Under the action of centrifugal force, the lubricating oil flows radially from the center of the orifice plate 82 to the periphery of the orifice plate 82 and the inner wall of the concentric hole 54 . Driven by the legs 87 and 88 of the oil fork 84 rotating together with the rotating shaft 50, the lubricating oil is pumped upward and forms a substantially parabolic P shape in the concentric hole 54, as shown in FIG. The lubricating oil then enters the eccentric bore 56 in fluid communication with the concentric bore 52 and reaches the end of the eccentric crank pin 52 . After being expelled from the end of the eccentric crankpin 52, the lubricating oil flows downward by gravity and is splashed by the various moving parts to lubricate and cool them.

In the example shown in FIG. 1 , an oil pump mechanism composed of an orifice plate 82 and an oil fork 84 is used. However, those skilled in the art should understand that the oil pumping mechanism is not limited thereto, and any mechanism capable of supplying lubricating oil into the concentric hole 54 of the rotating shaft 50 may be used. In addition, a vane pump can be used instead of the oil pump mechanism composed of the orifice plate 82 and the oil fork 84 shown in FIG. 1 . In addition, in the horizontal compressor, since most of the lubricating oil is stored on the high pressure side (at this time, the high pressure side constitutes the aforementioned lubricating oil storage portion), it is possible to use concentric holes extending from the high pressure side to the rotating shaft located on the low pressure side. The oil pipe is used as an oil pump mechanism, and the supply of lubricating oil can be realized through the pressure difference between the high pressure side and the low pressure side.

In addition, those skilled in the art should understand that the compression mechanism 20 and the driving mechanism 30 are not limited to the structures shown in the figures. On the contrary, the compression mechanism 20 can be a rotor type compression mechanism, a screw type compression mechanism, etc., and the drive mechanism 30 can be a hydraulic drive mechanism, a pneumatic drive mechanism and various transmission drive mechanisms arranged inside or outside the casing.

The following documents provide other detailed information of the rotary compressor related to the embodiment of the present invention: CN201206549Y, US2009/0068048A1, US2009/0068045A1, US2009/0068044A1 and US2009/0068043A1. The entire contents of these documents are incorporated herein by reference.

There must be enough lubricating oil in the compressor to ensure the normal operation of the compressor. In other words, when the amount of lubricating oil in the compressor, such as the oil level of the lubricating oil, is lower than a predetermined value, such as the minimum protection lubricating oil level, the compressor must be stopped to prevent the compressor from being damaged.

The oil level detection mechanism according to the present invention will be described below with reference to FIGS. 1-8 . Wherein, FIG. 2 is an enlarged view of the lower part of the rotary compressor shown in FIG. 1 . Fig. 3 is a schematic diagram of an oil level detection mechanism according to an embodiment of the present invention. 4 is a perspective view of a lower bearing integrated with an oil level sensor according to an embodiment of the present invention.

As shown in FIGS. 1-3 , the rotary compressor 10 according to the embodiment of the present invention further includes an oil level detection mechanism 100 disposed inside the compressor 10 . The oil level detection mechanism 100 according to the embodiment of the present invention includes an oil level sensor 120 in fluid communication with the inside of the concentric hole 54 of the rotating shaft 50 through the pressure acquisition channel 110 . In the example shown in FIG. 3 , the pressure collection channel 110 may include a pressure collection hole 112 extending through the sidewall of the rotating shaft 50 in a substantially radial direction, a pressure collection hole 112 disposed in the lower bearing housing 70 and in fluid communication with the pressure collection hole 112 . Circumferential oil groove 114 , and communication passage 116 in lower bearing housing 70 extending through lower bearing housing 70 in a generally radial direction and in fluid communication with circumferential oil groove 114 and fluid inlet 122 of oil level sensor 120 . The oil level sensor 120 may be provided at or near the lower bearing seat 70 . During the rotation of the rotation shaft 50, the pressure acquisition hole 112 on the rotation shaft 50 also rotates. Since the circumferential oil groove 114 corresponding to the rotation path of the pressure collection hole 112 is provided, the pressure collection hole 112 can always be in fluid communication with the circumferential oil groove 114, and then always be in fluid communication with the communication channel 116, thereby stably introducing the fluid into the The fuel level sensor 120 connected thereto.

Fig. 6 is a front view of an oil level sensor according to an embodiment of the present invention, wherein the housing of the oil level sensor is not shown in the drawing. 7 is a cross-sectional view of an oil level sensor according to an embodiment of the present invention, showing the oil level sensor in a disconnected state. 8 is a cross-sectional view of an oil level sensor according to an embodiment of the present invention, showing that the oil level sensor is in a conduction state.

As shown in FIGS. 6-8 , the oil level sensor 120 includes a substantially cylindrical housing 121 , a piston cap 123 capable of axially moving in the housing 121 , a piston head 125 that moves with the piston cap 123 , and a seal at one end of the housing 121 . The terminal 126 , the first contact 127 and the second contact 128 provided in the terminal 126 , and the return spring provided between the piston head 125 and the terminal 126 . A fluid inlet 122 is provided on a side wall of the shell 121 opposite to the terminal post 126 , and a discharge port 124 is formed on the side wall of the shell 121 . During the axial movement of the piston head 125, the fluid between the piston head 125 and the terminal post 126 is discharged through the discharge port 124 so as to reduce the resistance to the supply fluid. The piston rod 125 a of the piston head 125 extends through a through hole 131 formed in the terminal post 126 and is axially movable in the through hole 131 . The first contact 127 may include a plurality of pin portions 127A and 127B connected to each other but spaced apart from each other. In the example in the figure, the first contact 127 includes two pins 127A and 127B, but those skilled in the art should understand that the first contact 127 may include only one pin or more than two pins. The second contact 128 may include an annular contact piece 128A. The annular contact piece 128A is provided on the stepped portion of the stud 126 . The return spring 129 is in electrical communication with the annular contact piece 128A of the second contact 128 and the piston head 125 . In addition, as shown in FIG. 2 , the first contact 127 and the second contact 128 of the oil level sensor 120 are connected to the outside of the compressor through the adapter 150 provided on the casing 12 .

As shown in Figure 7, when the inlet 122 of the oil level sensor 120 is not supplied with fluid, the piston head 125 moves in the direction opposite to the first contact 127 and the second contact 128 under the action of the return spring 129, thereby disconnecting The first contact 127 and the second contact 128 . At this time, the oil level sensor 120 outputs no signal, or outputs a "0" signal.

As shown in Figure 8, when the inlet 122 of the oil level sensor 120 is supplied with fluid, the piston head 125 is pushed by the supplied fluid to overcome the force of the return spring 129 and move towards the first contact 127 and the second contact 128, The first contact 127 and the second contact 128 can be conducted when the piston head 125 is in contact with any one needle of the first contact 127 . At this time, the oil level sensor 120 outputs a conduction signal, or outputs a "1" signal.

Figure 6-8 depicts a specific fuel level sensor. Those skilled in the art should understand that the oil level sensor may be any type of sensor including a fluid pressure receiving part for receiving fluid pressure and a converting part capable of converting the fluid pressure into an electrical signal.

The process of detecting lubricating oil in the rotary compressor of the embodiment of the present invention will be described below. When there is an appropriate amount of lubricating oil in the casing 12 of the compressor, the lubricating oil entering the concentric hole 54 of the rotating shaft 50 forms a paraboloid P as shown in FIG. 3 under the action of centrifugal force. At this time, lubricating oil enters the fluid inlet 122 of the oil level sensor 120 through the pressure collection hole 112 on the side wall of the rotating shaft, the circumferential oil groove 114 formed in the lower bearing housing 70 and the communication channel 116 in the lower bearing housing 70 . As mentioned above, driven by the lubricating oil, the piston head 125 moves towards the first contact 127 and the second contact 128 and finally connects the first contact 127 and the second contact 128, thereby sending out a "1" signal , indicating the presence of an appropriate amount of lubricating oil in the compressor. On the contrary, when there is not enough lubricating oil in the casing 12 of the compressor, no lubricating oil reaches the fluid inlet 122 of the oil level sensor 120, so the oil level sensor 120 outputs a signal of "0", indicating that there is not enough lubricating oil in the compressor. of lubricating oil.

In order to detect the lubricating oil level in the compressor more accurately, a pressure collecting tube 118 protruding toward the axis of the concentric hole 54 may be provided in the pressure collecting hole 122 on the side wall of the rotating shaft. The lubricating oil level desired to be detected can be controlled by the inwardly protruding length of the pressure collection tube 118 (for example, the length L shown in FIGS. 9 and 11 ). As shown in FIG. 3 , when the distal end 119 of the pressure collection tube 118 is located within the oil surface represented by the parabola P, lubricating oil can enter the pressure collection tube 118 . During the movement along the pressure collection pipe 118 , the kinetic energy of the lubricating oil can be converted into pressure, so a certain pressure difference is generated at both ends of the pressure collection pipe 118 . When lubricating oil with a certain pressure enters the oil level sensor 120, the piston head 125 of the oil level sensor 120 is pushed to connect the first contact 127 and the second contact 128, thus outputting a signal of "1". When the distal end 119 of the pressure collecting tube 118 is outside the oil surface indicated by the parabola P, the lubricating oil cannot enter the oil level sensor 120 and outputs a signal of "0". Therefore, when the lubricating oil level expected to be detected (i.e. the lowest protection lubricating oil level) is set higher, a longer length of pressure acquisition tube 118 can be used, and when the lubricating oil level expected to be detected (i.e. the lowest protection level) When lubricating oil oil level) is set lower, can adopt the pressure collection pipe 118 of smaller length. In particular, the relationship between the minimum protection lubricating oil level of the compressor and the length of the pressure collection pipe 118 under specific working conditions can be determined through calculation or experimentation.

Referring to Fig. 11 in particular, the following relationship can be satisfied between the minimum protection lubricating oil level and the length of the pressure collection pipe 118:

$\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; -</span>\frac{{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; 60</span>}}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; 2000</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; ,</span>$

Wherein, H is the height of the minimum protection lubricating oil level S2 calculated from the end surface S0 of the rotating shaft 50, and the unit is mm;

L is the length of the pressure collection tube 118 protruding into the rotating shaft 50, and the unit is millimeter;

R is the inner radius of the rotating shaft 50, in millimeters;

h is the height of the central axis S1 of the pressure collection tube 118 counted from the end surface S0 of the rotating shaft 50, in millimeters;

n is the number of revolutions of the rotating shaft, in rev/min;

g is the acceleration due to gravity, and the unit is m/s2.

According to the above formula, for example, when h=32mm, L=6.9mm, n=2000rpm, R=9mm, g=9.81m/s ² , H≈22mm. That is, when the rotating speed is 2000 r/min and the length of the pressure collecting tube protruding into the rotating shaft is 6.9 mm, the minimum protective lubricating oil level that the oil level sensor can detect is about 22 mm. That is to say, when the lubricating oil level in the lubricating oil storage part is higher than 22 mm, the oil level sensor can output a signal of "1", indicating that the compressor can operate normally. When the lubricating oil level in the lubricating oil storage part is lower than 22 mm, the oil level sensor cannot output a "1" signal (that is, output a "0" signal), indicating that the lubricating oil in the compressor is insufficient, so the compressor protection The mechanism will stop the compressor.

In addition to the above-mentioned way of arranging the pressure collection tube, it is also possible to adjust the pressure collection hole 112 from a specific reference plane (for example, the reference plane S described in FIG. The height h of the end surface S0) is used to more accurately detect the lubricating oil level in the compressor. Specifically, when the lubricating oil level expected to be detected (that is, the minimum protective lubricating oil level) is set higher, the height of the pressure collection hole 112 from a specific reference surface can be set higher, and when the lubricating oil level expected to be detected When the oil level (that is, the minimum protection lubricating oil level) is set low, the height of the pressure collection hole 112 from a specific reference plane can be set low. In particular, the relationship between the lubricating oil level expected to be detected by the compressor under a specific working condition and the height of the pressure collection hole 112 from a specific reference plane can be determined through calculation or experiment.

In the example shown in FIG. 3 , the pressure acquisition channel 110 includes a pressure acquisition hole 112 disposed on the side wall of the rotating shaft, a circumferential oil groove 114 disposed on the lower bearing seat 70 , and a communication passage 116 extending through the lower bearing seat 70 , A pressure collection tube 118 disposed in the pressure collection hole 112 is optionally included. However, the configuration of the pressure collection channel 110 is not limited thereto, but may have various modifications. For example, the circumferential oil groove 112 may be provided on the rotating shaft 50 instead of the lower bearing housing 70 . In addition, for example, as shown in FIGS. 9 and 10 , a pressure collector 130 may be further provided between the rotary shaft 50 and the oil level sensor 120 . In the example of FIG. 9 , the pressure collector 130 is an annular member and includes a circumferential oil groove 114A that is in fluid communication with the pressure collection hole 112 on the rotating shaft 50 and is in fluid communication with the circumferential oil groove 114A and extends through the pressure collector. 130 of the communication channel 116A. In the example of FIG. 10 , a circumferential oil groove 114B may be provided on the rotating shaft 50 . The fluid inlet 122 of the oil level sensor 120 can be in fluid communication with the communication channel 116A of the pressure collector 130 directly or through other pipelines. By providing the pressure collection hole 130 , the oil level sensor 120 can be arranged more flexibly without modifying the structure of the lower bearing seat 70 .

In the example of the oil level detecting mechanism according to the present invention shown in FIG. 11 . An oil temperature sensor 140 may be further provided. The oil temperature sensor 140 can share a lead wire 142 with the oil level sensor 120 . Specifically, the lead wires 141 and 142 output the signal of the oil level sensor 120 , while the lead wires 142 and 143 output the signal of the oil temperature sensor. In this embodiment, the compressor can be controlled not only according to the signal of the oil level sensor 120 but also according to the signal of the oil temperature sensor 140 . Thus, double protection is provided for the compressor.

In the embodiment shown in the figures, the oil level sensing mechanism 100 is in fluid communication with the concentric bore 54 . However, those skilled in the art should understand that the concentric hole 54 can be replaced by a non-concentric hole extending axially along the rotating shaft 50 . In addition, according to the internal design of the compressor, the oil level detection mechanism 100 may also be in fluid communication with the eccentric hole 56 of the rotating shaft 50 . Even if the hole 54 or 56 is a non-concentric hole, due to the centrifugal force caused by the rotation of the rotating shaft, the oil level detection mechanism of the present invention can still operate normally.

In an embodiment of the present invention, a pressure sensor comprising a piston, a contact and a spring is described as an oil level sensor. Those skilled in the art should understand that any suitable pressure sensor known in the art, especially a pressure switch, can be used as the oil level sensor.

In the above embodiments, it is described that the oil level sensor 120 is disposed in the housing 12 and can be in fluid communication with the communication channel 116 in the lower bearing housing 70 or the communication channel 116A in the pressure collector 130 directly or through an additional pipeline . But the present invention is not limited thereto. As shown in FIGS. 13A and 13B , the oil level sensor 120 can be disposed outside the housing 12 and communicate fluidly with the communication channel 116 in the lower bearing housing 70 (or the communication channel in the pressure collector) through the connecting pipe 160 . The connection pipe 160 can be arranged horizontally (as shown in FIG. 13A ) or inclined (as shown in FIG. 13B ). With this configuration, various components within the compressor can be arranged more flexibly.

Although various embodiments of the present invention have been described in detail herein, it should be understood that the present invention is not limited to the specific embodiments described and shown in detail herein, and can be developed by those skilled in the art without departing from the spirit and scope of the present invention. Other modifications and variations will occur to the skilled artisan. All such modifications and variations are within the scope of the present invention. Moreover, all components described here may be replaced by other technically equivalent components.

Claims (37)

1. A rotary compressor comprising: a housing (12) including a lubricating oil reservoir for containing lubricating oil; a compression mechanism (20) disposed within the housing (12); A driving mechanism (30) for driving the compression mechanism (20), the driving mechanism (30) includes a rotating shaft (50), and the rotating shaft (50) is provided with a an extended through hole (54, 56) through which the rotating shaft (50) is in fluid communication with the lubricating oil reservoir; and An oil level sensor (120) is in fluid communication with through holes (54, 56) in said rotating shaft (50) through a pressure acquisition channel (110). 2. The rotary compressor according to claim 1, further comprising a lower bearing housing (70) for supporting the rotary shaft (50), Wherein the pressure collection channel (110) includes: a pressure collection hole (112) extending through the side wall of the rotation shaft (50) and in fluid communication with the through holes (54, 56) in the rotation shaft (50) ), a circumferential oil groove (114) formed on the rotating shaft (50) or the lower bearing seat (70) and in fluid communication with the pressure collection hole (112), and extending through the lower bearing seat (70) and a communication passage (116) in fluid communication with said circumferential oil groove (114) and said oil level sensor (120). 3. The rotary compressor according to claim 1, further comprising a pressure collector (130) disposed between the rotary shaft (50) and the oil level sensor (120), Wherein the pressure collection channel (110) includes: a pressure collection hole (112) extending through the side wall of the rotation shaft (50) and in fluid communication with the through holes (54, 56) in the rotation shaft (50) ), a circumferential oil groove (114A, 114B) formed on the rotating shaft (50) or the pressure collector (130) and in fluid communication with the pressure collection hole (112), and extending through the pressure A collector (130) and a communication passage (116A) in fluid communication with the circumferential oil grooves (114A, 114B) and the oil level sensor (120). 4. The rotary compressor according to claim 2 or 3, wherein the pressure collection channel (110) further comprises a through hole arranged in the pressure collection hole (112) and facing the rotation axis (50) The axis of (54,56) protrudes from the pressure collection tube (118). 5. The rotary compressor according to claim 4, wherein the length of the pressure collecting pipe (118) is determined according to a minimum protective lubricating oil level in the lubricating oil storage. 6. The rotary compressor according to claim 5, wherein the higher the minimum protection lubricating oil level is set, the longer the length of the pressure collection pipe (118) is set. 7. The rotary compressor according to claim 5, wherein the minimum protection lubricating oil level and the length of the pressure collection pipe (118) satisfy the following relationship: $\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; -</span>\frac{{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; L</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; 60</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; 2000</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; ,</span>$ Wherein, H is the height of the minimum protective lubricating oil level calculated from the end surface (S0) of the rotating shaft (50), in millimeters; L is the length of the pressure collection tube (118) protruding into the rotation shaft (50), in millimeters; R is the inner radius of the rotating shaft (50), in millimeters; h is the height of the central axis (S1) of the pressure collection tube (118) counted from the end surface (S0) of the rotating shaft (50), in millimeters; n is the number of revolutions of the rotating shaft, and the unit is rev/min; g is the acceleration due to gravity, the unit is m/ ^s2 . 8. The rotary compressor according to claim 2 or 3, wherein the height of the pressure collection hole (112) from a specific reference surface (S) is determined according to the minimum protection lubricating oil level in the lubricating oil storage part to make sure. 9. The rotary compressor according to claim 8, wherein the higher the minimum protection lubricating oil level is set, the higher the height of the pressure collection hole (112) is set. 10. The rotary compressor according to claim 8, wherein the reference surface (S) is a bottom surface of the rotary compressor or an end surface of the rotary shaft (50). 11. The rotary compressor according to claim 1, further comprising an oil pumping mechanism (80), the oil pumping mechanism (80) comprising an orifice (82) arranged at the end of the rotating shaft (50) and An oil fork (84) is arranged in the through holes (54, 56) of the rotating shaft (50). 12. The rotary compressor according to claim 1, further comprising an oil pumping mechanism (80), the oil pumping mechanism (80) comprising a vane pump arranged at an end of the rotating shaft (50). 13. The rotary compressor according to claim 1, wherein the rotary compressor is a horizontal rotary compressor and its internal space is divided into a high-pressure side and a low-pressure side by a sound-absorbing plate, and the high-pressure side constitutes the lubrication oil storage, and The rotary compressor further includes an oil pump mechanism (80), which is an oil pipe extending from the lubricating oil storage part to the through holes (54, 56) of the rotary shaft (50). . 14. The rotary compressor according to claim 1, wherein said through hole (54, 56) includes a concentric hole portion (54) concentric with said rotation axis (50) and ) radially offset eccentric hole portion (56). 15. The rotary compressor of claim 1, wherein said oil level sensor (120) is a pressure sensor. 16. The rotary compressor of claim 1, wherein said oil level sensor (120) is a pressure switch. 17. The rotary compressor of claim 1, wherein said oil level sensor (120) comprises: a fluid pressure receiving portion for receiving fluid pressure; and A converting portion capable of converting the fluid pressure into an electrical signal. 18. The rotary compressor according to claim 17, wherein the fluid pressure receiving portion comprises: shell (121), and a piston head (125) capable of axial movement within said housing (121); The conversion section includes: terminal (126), a first contact (127) and a second contact (128) disposed within said terminal (126), and a spring (129) providing electrical communication between said piston head (125) and said second contact (128) and providing a restoring force to said piston head (125), Wherein when the piston head (125) is in contact with the first contact (127), the oil level sensor outputs an electrical signal. 19. The rotary compressor according to claim 18, wherein said first contact (127) comprises a plurality of needles (127A, 127B) spaced apart from each other. 20. A rotary compressor according to claim 18, wherein said second contact (128) comprises an annular contact piece (128A) in electrical contact with said spring (129). 21. The rotary compressor of claim 1, further comprising an oil temperature sensor (140). 22. The rotary compressor of claim 21, wherein the oil temperature sensor (140) has a common lead (142) with the oil level sensor (120). 23. The rotary compressor according to claim 2, wherein the oil level sensor (120) is disposed near the lower bearing seat (70). 24. The rotary compressor according to claim 2, wherein said oil level sensor (120) is directly connected with a communication channel (116) in said lower bearing housing (70). 25. The rotary compressor according to claim 2, wherein the oil level sensor (120) is connected with the communication channel (116) in the lower bearing seat (70) through an additional pipeline. 26. The rotary compressor according to claim 3, wherein the oil level sensor (120) is directly connected with the communication channel (116A) in the pressure collector (130). 27. The rotary compressor according to claim 3, wherein the oil level sensor (120) is connected with the communication channel (116A) in the pressure collector (130) through an additional pipeline. 28. The rotary compressor of claim 1, wherein the rotary compressor is a scroll compressor, or a screw compressor, or a rotary compressor. 29. The rotary compressor according to claim 2 or 3, wherein the oil level sensor (120) is arranged inside the housing (12). 30. The rotary compressor according to claim 2, wherein said oil level sensor (120) is arranged outside said housing (12). 31. The rotary compressor according to claim 30, wherein said pressure collection passage (110) further comprises a connecting duct (160) in fluid communication with a communication passage (116) in said lower bearing housing (70). 32. The rotary compressor according to claim 3, wherein said oil level sensor (120) is arranged outside said housing (12). 33. The rotary compressor according to claim 32, wherein the pressure collection channel (110) further comprises a connecting pipe (160) in fluid communication with the communication channel (116A) in the pressure collector (130). 34. The rotary compressor according to claim 31 or 33, wherein the connecting pipe (160) is arranged horizontally or inclined. 35. A rotating machine comprising: a housing including a lubricating oil reservoir for containing lubricating oil; a rotating shaft disposed in the housing, the rotating shaft is provided with a through hole extending in the axial direction of the rotating shaft, and the rotating shaft is in fluid communication with the lubricating oil storage part through the through hole; as well as An oil level sensor in fluid communication with the through hole in the rotating shaft through the pressure acquisition channel. 36. A rotary machine as claimed in claim 35, further comprising a bearing housing for supporting said rotary shaft, Wherein the pressure acquisition channel includes: a pressure acquisition hole extending through the side wall of the rotating shaft and in fluid communication with a through hole in the rotating shaft, formed on the rotating shaft or the bearing seat and connected to the A circumferential oil groove in fluid communication with the pressure collection hole, a communication channel extending through the bearing seat and in fluid communication with the circumferential oil groove and the oil level sensor. 37. The rotary machine of claim 35, further comprising a pressure pick-up disposed between the rotary shaft and the oil level sensor, Wherein the pressure acquisition channel includes: a pressure acquisition hole extending through the side wall of the rotation shaft and in fluid communication with a through hole in the rotation shaft, formed on the rotation shaft or the pressure acquisition device and connected with A circumferential oil groove in fluid communication with the pressure collection hole, a communication passage extending through the pressure collector and in fluid communication with the circumferential oil groove and the oil level sensor.

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