Velocity and direction finding device, compressor, refrigeration device

Abstract

This application provides a speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft, comprising: a rotating shaft; a notch measuring portion cut into a portion of the surface of the rotating shaft; an eddy current displacement sensor disposed corresponding to the notch measuring portion; and an eddy current signal processing module connected to the eddy current displacement sensor, which receives and processes eddy current signals from the eddy current displacement sensor when the rotating shaft rotates. The notch measuring portion includes at least a first inclined surface and a second inclined surface cut into the surface of the rotating shaft and distributed along the rotation direction of the rotating shaft. The first inclined surface and the second inclined surface have different inclination angles relative to the surface of the rotating shaft. This speed and direction measuring device has a simple and compact structure, is easy to use, and only requires one asymmetrical notch measuring portion and one corresponding eddy current displacement sensor on the surface of the rotating shaft. It has low installation space requirements and can be better adapted to different applications of the rotating shaft.

Description

Technical Field

[0001] This application relates to the field of refrigeration / cooling equipment technology, specifically to a speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft, a compressor having the speed and direction measuring device, and a refrigeration system including the compressor. Background Technology

[0002] In the field of compressor control, real-time monitoring of rotor speed and rotation direction is a crucial technical means to ensure the safe operation of the system. Currently, a common approach involves installing at least two measuring sections on the rotor surface and correspondingly configuring at least two sensors for detection. When the measuring section passes the sensor, it generates a corresponding signal. By analyzing the changes in the output signals from the two sensors, both the rotor speed and the rotor's rotation direction can be calculated.

[0003] However, in the existing technology, multiple measuring parts need to be processed on the rotor, which increases the complexity of the rotor processing technology. Secondly, multiple measuring parts need to be configured with multiple sensors, which places high demands on the sensor installation space. Therefore, the detection schemes in the existing technology have obvious shortcomings in terms of economic efficiency and system integration. Summary of the Invention

[0004] This application aims to provide a speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft, a compressor having the speed and direction measuring device, and a refrigeration system including the compressor, so as to at least solve or alleviate some of the problems existing in the prior art.

[0005] This application provides a speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft, comprising: a rotating shaft; a notch measuring portion cut into a portion of the surface of the rotating shaft; an eddy current displacement sensor disposed corresponding to the notch measuring portion and detecting the distance between itself and the surface of the notch measuring portion; and an eddy current signal processing module connected to the eddy current displacement sensor and receiving and processing eddy current signals from the eddy current displacement sensor when the rotating shaft rotates, wherein the notch measuring portion includes at least a first inclined surface and a second inclined surface cut into the surface of the rotating shaft and distributed along the rotation direction of the rotating shaft, and the first inclined surface and the second inclined surface have different inclination angles relative to the surface of the rotating shaft.

[0006] In an optional technical solution, the inclination angle between the first inclined surface or the second inclined surface and the surface of the rotation axis is between 70 degrees and 90 degrees.

[0007] In an optional technical solution, the inclination angle between the first inclined surface or the second inclined surface and the surface of the rotating shaft is between 30 degrees and 60 degrees.

[0008] In an optional technical solution, the eddy current signal processing module includes a high-pass filter module, which receives the eddy current signal from the eddy current displacement sensor and outputs a filtered high-frequency signal.

[0009] In an optional technical solution, the speed and direction measuring device for measuring the rotational speed and direction of the rotating shaft further includes a signal slope calculation module that takes a predetermined proportion of the signal peak value from the eddy current signal processing module as the slope evaluation peak value and calculates the output signal slope based on the slope evaluation peak value; and a rotation direction determination module that compares the signal slope output by the signal slope calculation module with the preset slope value of the first slope or the second slope to determine the rotation direction of the rotating shaft.

[0010] In an optional technical solution, the specified ratio is 70%-90% of the signal peak value of the eddy current signal processing module.

[0011] In an optional technical solution, the speed and direction measuring device for measuring the rotational speed and direction of the rotating shaft further includes a rotational speed determination module that determines the rotational speed of the rotating shaft based on the signal peak value from the eddy current signal processing module.

[0012] Another aspect of this application provides a compressor, including a housing, a motor, and an impeller, wherein it also includes a speed and direction measuring device provided in any of the above technical solutions for measuring the rotational speed and direction of the rotating shaft.

[0013] In an optional technical solution, the compressor further includes a compressor frequency modulation module that issues a frequency modulation command to increase or decrease the compressor speed, and the speed and direction measuring device only operates when the compressor frequency modulation module issues a frequency modulation command to increase the compressor speed.

[0014] Another aspect of this application provides a refrigeration apparatus, including a compressor, a condenser, and an evaporator connected in sequence via refrigerant pipes, wherein the compressor is the compressor provided in any of the above-described technical solutions. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the speed and direction measuring device provided in the embodiments of this application.

[0016] Figure 2 This is a schematic diagram of the signals generated by the eddy current displacement sensor and the eddy current signal processing module when the rotating shaft rotates clockwise in the embodiment of this application.

[0017] Figure 3 This is a schematic diagram of the signals generated by the eddy current displacement sensor and the eddy current signal processing module when the rotating shaft rotates counterclockwise in the embodiment of this application.

[0018] Figure 4This is a schematic diagram of the signal processing module provided in the embodiments of this application.

[0019] Reference numerals: speed and direction measuring device 100, rotating shaft 101, notch measuring unit 102, eddy current displacement sensor 103, first inclined plane 104, second inclined plane 105, first inclined plane segment 1041, second inclined plane segment 1051, eddy current signal processing module 200, high-pass filter module 201, signal slope calculation module 202, rotation direction judgment module 203, rotation speed judgment module 204. Detailed Implementation

[0020] It should be noted that the following will use examples to illustrate the working principle, features and advantages of the refrigeration equipment according to this application. However, it should be understood that all descriptions are given for illustrative purposes only and should not be construed as limiting the application in any way.

[0021] Furthermore, for any single technical feature described or implied in the embodiments mentioned herein, or any single technical feature shown or implied in the various figures, this application still allows for any combination or deletion of these technical features (or their equivalents) without any technical obstacle, thereby obtaining more other embodiments of this application that may not be directly mentioned herein.

[0022] <First Implementation Method>

[0023] Figure 1 This is a schematic diagram of the speed and direction measuring device provided in the embodiments of this application, such as... Figure 1 As shown, the speed and direction measuring device 100 provided in this embodiment includes: a rotating shaft 101, a notch measuring portion 102 cut into a portion of the surface of the rotating shaft 101, and an eddy current displacement sensor 103. The notch measuring portion 102 includes at least a first inclined surface 104 and a second inclined surface 105 cut into the surface of the rotating shaft 101 and distributed along the rotation direction of the rotating shaft 101. The first inclined surface 104 and the second inclined surface 105 have different inclination angles relative to the surface of the rotating shaft 101.

[0024] The eddy current displacement sensor 103 is positioned in the axial direction of the rotating shaft 101 corresponding to the location of the notch measuring part 102, and detects the distance between the eddy current displacement sensor 103 and the surface of the rotating shaft 101 in real time. Preferably, the rotating shaft 101 is cylindrical in shape. When the rotating shaft 101 rotates around the central axis of the cylinder, when the part of the rotating shaft 101 surface without the notch measuring part 102 rotates to the position corresponding to the eddy current displacement sensor 103, the distance detected by the eddy current displacement sensor 103 to the surface of the rotating shaft 101 is equal. When the notch measuring part 102 rotates to the position corresponding to the eddy current displacement sensor 103, because the inclination angles of the first inclined surface 104 and the second inclined surface 105 relative to the surface of the rotating shaft 101 are different, the distance detected by the eddy current displacement sensor 103 changes with the change of the first inclined surface 104 and the second inclined surface 105 of the notch measuring part 102 cutting into the surface of the rotating shaft 101. In other words, when the notch measuring unit 102 corresponds to the first inclined surface 104, it will detect a change in the distance between the notch measuring unit 102 and the first inclined surface 104; and when the notch measuring unit 102 corresponds to the second inclined surface 105, it will detect a change in the distance between the notch measuring unit 102 and the first inclined surface 105. Since the first inclined surface 104 and the second inclined surface 105 have different inclination angles relative to the surface of the rotating shaft 101, the different detected distance changes can be used to determine the order in which the first inclined surface 104 and the second inclined surface 105 pass through the corresponding position of the notch measuring unit 102 during the rotation of the rotating shaft 101, thereby determining the direction of rotation of the rotating shaft 101.

[0025] Meanwhile, if any point on the first inclined plane 104 or the second inclined plane 105 is selected as a reference, the rotational speed of the rotating shaft 101 can be determined.

[0026] Therefore, the current rotation direction and speed of the rotating shaft 101 can be quickly and effectively determined using only a notch measuring section 102 with different inclination angles (first inclined surface 104 and second inclined surface 105) and an eddy current displacement sensor 103. This improves the economic efficiency and system integration advantages of the rotating shaft in terms of steering and speed measurement.

[0027] Combination Figure 1 As shown, the speed and direction measuring device 100 provided in this embodiment of the application is also provided with an eddy current signal processing module 200. The eddy current displacement processing module 200 is connected to the eddy current displacement sensor 103. When the rotating shaft 101 rotates, the eddy current displacement sensor 103 detects the distance between itself and the position corresponding to the rotating shaft 101 when it rotates to the position corresponding to the eddy current displacement sensor 103 in real time. Then, the eddy current signal processing module 200 receives and processes the eddy current signal detected by the eddy current displacement sensor 103, thereby determining the current rotation direction and rotation speed of the rotating shaft 101.

[0028] Specifically, Figure 2 This is a schematic diagram of the signal generated by the eddy current signal processing module 200 when the rotating shaft rotates clockwise in the embodiment of this application. Figure 3 This is a schematic diagram of the signal generated by the eddy current signal processing module 200 when the rotating shaft rotates counterclockwise in the embodiments of this application, as shown below. Figure 2 and Figure 3 As shown, when the rotating shaft 101 rotates clockwise, and the notch measuring unit 102 has not rotated to the position corresponding to the eddy current displacement sensor 103, the waveform of the spacing signal detected by the eddy current displacement sensor 103 and generated by the eddy current signal processing module 200 is basically a horizontal straight line, that is, the spacing between the surface of the rotating shaft 101 and the eddy current displacement sensor 103 is basically equal when the rotating shaft 101 rotates. When the notch measuring unit 102 rotates to the position corresponding to the eddy current displacement sensor 103, the first inclined surface 104 first rotates past the eddy current displacement sensor 103. At this time, the waveform of the spacing signal detected by the eddy current displacement sensor 103 and generated by the eddy current signal processing module 200 presents a first inclined surface segment 1041 corresponding to the inclination angle of the first inclined surface 104. When the second inclined surface 105 rotates past the eddy current displacement sensor 103, the waveform of the spacing signal detected by the eddy current displacement sensor 103 and generated by the eddy current signal processing module 200 presents a second inclined surface segment 1051 corresponding to the inclination angle of the second inclined surface 105.

[0029] When the rotating shaft 101 rotates counterclockwise, when the notch measuring unit 102 rotates to the position corresponding to the eddy current displacement sensor 103, the second inclined surface 105 first rotates past the eddy current displacement sensor 103, and the spacing signal waveform presents the second inclined surface segment 1051 corresponding to the tilt angle of the second inclined surface 105. Then the first inclined surface 104 rotates past the eddy current displacement sensor 103, and the spacing signal waveform presents the first inclined surface segment 1041 corresponding to the tilt angle of the first inclined surface 104.

[0030] That is, when the notch measuring unit 102 is not rotated to the eddy current displacement sensor 103, the spacing signal waveform is a horizontal straight line segment. When the notch measuring unit 102 rotates clockwise to the eddy current displacement sensor 103, the spacing signal presents a spacing signal waveform characteristic corresponding to the cross-sectional contour of the notch measuring unit 102, with the first inclined segment 1041 first and the second inclined segment 1051 following. When the notch measuring unit 102 rotates counterclockwise to the eddy current displacement sensor 103, the spacing signal presents a spacing signal waveform characteristic corresponding to the cross-sectional contour of the notch measuring unit 102, with the second inclined segment 1051 first and the first inclined segment 1041 following.

[0031] Therefore, based on the above characteristics of the spacing signal waveform, it can be determined whether the rotating shaft 101 rotates clockwise or counterclockwise, thereby determining the rotation direction of the rotating shaft 101.

[0032] Meanwhile, a notch measuring section 102 is cut into the surface of the rotating shaft 101. When the rotating shaft 101 rotates, the current rotational speed of the rotating shaft 101 can be calculated based on the frequency of occurrence of the signal segment waveform corresponding to the notch measuring section 102 (i.e., the first inclined segment 1041 and / or the second inclined segment 1051) in the spacing signal waveform detected by the eddy current displacement sensor 103 and generated by the eddy current signal processing module 200, corresponding to the first inclined segment 1041 and / or the second inclined segment 1051. Specifically, the number of times the signal segment corresponding to the notch measuring section 102 appears in the spacing signal generated by the eddy current signal processing module 200 within a specified time is calculated. Each occurrence represents one revolution of the rotating shaft 101. By calculating the ratio of the number of occurrences of the signal segment corresponding to the notch measuring section 102 to the specified time, the current rotational speed of the rotating shaft 101 can be calculated.

[0033] Through the above implementation methods, according to as follows Figure 2 The spacing signal waveform characteristics detected by the eddy current displacement sensor 103 and processed by the eddy current signal processing module 200 can quickly and effectively determine the current rotation direction and speed of the rotating shaft 101 using only a notch measuring part 102 with different tilt angles (first inclined surface 104 and second inclined surface 105) and an eddy current displacement sensor 103.

[0034] As described above, the speed and direction measuring device 100 for measuring the rotational speed and direction of the rotating shaft 101 provided in this application embodiment has a simple and compact structure and is easy to use. It only has a notch measuring part 102 opened on the surface of the rotating shaft 101 and a corresponding eddy current displacement sensor 103. It has low requirements for installation space and can be better applied to different applications of the rotating shaft 101.

[0035] Furthermore, in a preferred embodiment of this application, the inclination angle (i.e., the angle formed by the first inclined surface 104 or the second inclined surface 105 with the surface of the rotation shaft 101) between 70 degrees and 90 degrees. The inclination angle between the other of the first inclined surface 104 or the second inclined surface 105 and the surface of the rotation shaft 101 between 30 degrees and 60 degrees.

[0036] Through the above implementation, a large difference in tilt angle is controlled between the first inclined surface 104 and the second inclined surface 105. For example, the tilt angle between the first inclined surface 104 and the surface of the rotating shaft 101 is set to 90 degrees, and the tilt angle between the second inclined surface 105 and the surface of the rotating shaft 101 is set to 30 degrees or 45 degrees. When the rotating shaft 101 rotates clockwise, the spacing signal waveform generated by the eddy current displacement sensor 103 and the eddy current signal processing module 200 is significantly different from the spacing signal waveform generated by the eddy current displacement sensor 103 and the eddy current signal processing module 200 when the rotating shaft 101 rotates counterclockwise. This allows for a faster and more accurate determination of the current rotation direction of the rotating shaft 101. In other words, the greater the asymmetry of the cross-sectional profile of the notch measuring part 102, the more accurate the current rotation direction detection result of the rotating shaft 101 detected by the eddy current displacement sensor 103 and obtained by the eddy current signal processing module 200.

[0037] In particular, when the inclination angle of one of the first inclined surfaces 104 or the second inclined surfaces 105 is 90 degrees, that is, perpendicular to the tangent of the surface of the rotating shaft 101, the cutting process of the first inclined surface 104 or the second inclined surface 105 is also simpler. At the same time, the spacing signal waveform corresponding to the first inclined surface 104 or the second inclined surface 105 is also more prominent and obvious, making it easier to determine the direction of rotation and speed of the rotating shaft 101.

[0038] In other preferred embodiments of this application, the eddy current signal processing module 200 further includes a high-pass filter module 201, which receives the eddy current signal from the eddy current displacement sensor 103 and outputs the filtered high-frequency signal.

[0039] Specifically, when the eddy current signal detected by the eddy current displacement sensor 103 is transmitted to the eddy current signal processing module 200, it first passes through the high-pass filter module 201 to remove or attenuate low-frequency signals, retaining only the high-frequency signals that reflect the rotational speed of the rotating shaft 101 and the distance between the eddy current displacement sensor 103 and the surface of the rotating shaft 101. That is, the high-pass filter module 201 removes low-frequency components that may be present in the output signal of the eddy current displacement sensor 103, such as fixed DC bias, temperature drift, power fluctuations, or circuit imbalances, which could cause slowly changing low-frequency components. Only high-frequency pulse signals related to changes in target distance and rotational speed are retained, improving the accuracy of the rotational speed and direction measurement of the rotating shaft 101. This avoids fluctuations in the distance signal generated by the eddy current signal processing module 200 due to low-frequency DC voltage signals, which could affect the measurement of the rotational speed and direction of the rotating shaft 101.

[0040] Figure 4 This is a schematic diagram of the signal processing module provided in the embodiments of this application. (See attached diagram.) Figure 4As shown, in a preferred embodiment of this application, the speed and direction measuring device 100 for measuring the rotational speed and direction of the rotating shaft 101 further includes: a signal slope calculation module 202, a rotational direction judgment module 203, and a rotational speed judgment module 204.

[0041] Specifically, when the speed and direction measuring device 100 provided in this application measures the rotational speed and direction of the rotating shaft 101, the signal slope calculation module 202 uses a predetermined proportion of the signal peak value from the eddy current signal processing module 200 as the slope evaluation peak value, and calculates the slope of the eddy current signal rising from the horizontal segment to the predetermined proportion value and the slope of the eddy current signal falling from the predetermined proportion value back to the horizontal segment. At this time, the rotation direction determination module 203 compares the calculated slope of the signal segment with the preset slope value of the first inclined plane 104 or the second inclined plane 105, that is, the tilt angle of the first inclined plane 104 or the second inclined plane 105 relative to the surface of the rotating shaft 101. If the slope rising from the horizontal segment to the predetermined proportion value matches the preset slope value of the first inclined plane 104, and the slope falling from the predetermined proportion value back to the horizontal segment matches the preset slope value of the second inclined plane 105, then it is determined that the rotating shaft 101 is currently rotating clockwise.

[0042] Conversely, if the slope from the horizontal segment to the specified ratio matches the preset slope value of the second inclined plane 105, and the slope from the specified ratio to the horizontal segment matches the preset slope value of the first inclined plane 104, then it is determined that the current rotating axis 101 is rotating counterclockwise.

[0043] More preferably, the specified ratio is 70%-90% of the peak value of the signal output by the eddy current signal processing module 200. More preferably, the specified ratio can be 80% of the peak value of the signal output by the eddy current signal processing module 200.

[0044] By setting the specified ratio to a value between 70% and 90% of the signal peak, such as preferably one of 75%, 80%, or 85%, the influence of high-frequency noise, sampling jitter, or signal distortion on the signal peak can be effectively avoided, thus preventing noise fluctuations from affecting the calculation results when the actual peak is used as the calculation benchmark.

[0045] Simultaneously, the preferred rotation speed determination module 204 determines the rotation speed of the rotating shaft 101 based on the signal peak value from the eddy current signal processing module 200. Specifically, it calculates the number of times the peak value of the signal waveform appears in the spacing signal generated by the eddy current signal processing module 200 within a specified time. Each appearance represents one rotation of the rotating shaft 101. By calculating the ratio of the number of times the peak value of the signal waveform appears to the specified time, the current rotation speed of the rotating shaft 101 can be calculated.

[0046] The above-described embodiments enable the rapid and effective determination of the current rotation direction and speed of the rotating shaft 101 using only a notch measuring section 102 with an asymmetrical cross-sectional profile and a corresponding eddy current displacement sensor 103. The speed and direction measuring device 100 for measuring the rotational speed and direction of the rotating shaft 101 provided in this application embodiment has a simple and compact structure and is easy to use. Because it only requires a notch measuring section 102 formed on the surface of the rotating shaft 101 and a corresponding eddy current displacement sensor 103, it has low installation space requirements, reduces the number of parts, and lowers processing and installation costs, making it more suitable for different applications of the rotating shaft 101.

[0047] <Second Implementation Method>

[0048] The second embodiment of this application, which uses the same names and symbols as the embodiments described above, is the same content and will not be repeated here.

[0049] Another aspect of this application provides a compressor, including a housing, a motor, an impeller, and a speed and direction measuring device 100 provided in the first embodiment for measuring the rotational speed and direction of rotation of a rotating shaft 101. The compressor also includes a compressor frequency modulation module (not shown), which issues frequency modulation commands to increase or decrease the compressor speed. The speed and direction measuring device 100 only operates when the compressor frequency modulation module issues a frequency modulation command to increase the compressor speed.

[0050] Through the above implementation method, when the compressor frequency adjustment module adjusts the compressor frequency, the speed and direction of rotation of the compressor rotating shaft 101 are detected in real time by the speed and direction measuring device 100. This allows for a faster and simpler determination of the rotation speed of the compressor rotating shaft 101, which is then fed back to the compressor frequency adjustment module. This facilitates the control of the compressor speed to be adjusted at a predetermined rate until the target speed (i.e., the target frequency) is reached.

[0051] Another aspect of this application provides a refrigeration device (not shown), including a compressor, a condenser, and an evaporator connected in sequence via refrigerant pipes, wherein the compressor is the compressor provided in the embodiments of this application.

[0052] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft, comprising: Rotation axis; The notch measuring section is cut into a portion of the surface of the rotating shaft; An eddy current displacement sensor is provided corresponding to the notch measuring part to detect the distance between itself and the surface of the notch measuring part. An eddy current signal processing module, connected to the eddy current displacement sensor, receives and processes eddy current signals from the eddy current displacement sensor when the rotating shaft rotates. Its features are, The notch measuring section includes at least a first inclined surface and a second inclined surface that cut into the surface of the rotating shaft and are distributed along the rotation direction of the rotating shaft. The first inclined surface and the second inclined surface have different inclination angles relative to the surface of the rotating shaft.

2. The speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft as described in claim 1, characterized in that, The angle of inclination between the first inclined plane or the second inclined plane and the surface of the rotation axis is between 70 degrees and 90 degrees.

3. The speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft as described in claim 2, characterized in that, The angle of inclination between the first inclined plane or the second inclined plane and the surface of the rotating shaft is between 30 degrees and 60 degrees.

4. The speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft as described in any one of claims 1-3, characterized in that, The eddy current signal processing module includes a high-pass filter module, which receives the eddy current signal from the eddy current displacement sensor and outputs the filtered high-frequency signal.

5. The speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft as described in claim 4, characterized in that, It also includes, The signal slope calculation module takes a specified proportion of the signal peak value from the eddy current signal processing module as the slope evaluation peak value, and calculates the output signal slope based on the slope evaluation peak value. The rotation direction determination module compares the signal slope output by the signal slope calculation module with the preset slope value of the first slope or the second slope to determine the rotation direction of the rotating shaft.

6. The speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft as described in claim 5, characterized in that, The specified ratio is 70%-90% of the peak signal value of the eddy current signal processing module.

7. The speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft as described in claim 4, characterized in that, It also includes, The rotation speed determination module determines the rotation speed of the rotating shaft based on the signal peak value from the eddy current signal processing module.

8. A compressor, comprising a housing, a motor, and an impeller, characterized in that, It also includes, The speed and direction measuring device for measuring the rotational speed and direction of a rotating shaft as described in any one of claims 1-7.

9. The compressor as claimed in claim 8, characterized in that, It also includes, The compressor frequency control module issues frequency control commands to increase or decrease the compressor speed. The speed and direction measuring device only operates when the compressor frequency modulation module issues a frequency modulation command to increase the compressor speed.

10. A refrigeration apparatus comprising a compressor, a condenser, and an evaporator connected in sequence via refrigerant pipes, wherein the compressor is the compressor described in claim 8 or 9.

Images