Packaged compressor

Abstract

A packaged compressor (1) is provided with the following elements in a package (4): a compressor body (2); an oil collector (3) that collects oil separated from air discharged from the compressor body (2); an oil level gauge (11) for checking the oil level position of the oil stored in the oil collector (3), the oil level gauge (11) being installed on the outer wall of the oil collector (3); and an imaging unit (12) that acquires an image of the oil level gauge (11). The packaged compressor (1) can output, to the outside of the package (4), information pertaining to the oil level position based on the image acquired by the imaging unit (12).

Description

Package type compressor

[0001] The present disclosure relates to a packaged compressor.

[0002] Patent Document 1 discloses a compressor equipped with an oil recovery device that separates and recovers oil contained in the discharge air discharged from the compressor body by centrifugal force, and an oil level gauge that is attached to the oil recovery device and visually displays the oil level of the oil stored in the oil recovery device.

[0003] Patent No. 6266995

[0004] When the compressor of Patent Document 1 includes a compressor body, an oil recovery device, and an oil level gauge housed in a package, i.e., when the compressor is a packaged compressor, the oil level gauge cannot be visually inspected without removing the cover that constitutes the package. In other words, it is impossible to check whether the oil recovery device contains an appropriate amount of oil (whether oil needs to be replenished) without removing the cover of the package. At least in this respect, the compressor of Patent Document 1 requires complicated inspection of the oil recovery device.

[0005] An object of the present disclosure is to simplify inspection of an oil recovery device in a package-type compressor equipped with an oil level gauge for the oil recovery device.

[0006] One aspect of the present disclosure provides a package-type compressor comprising: a package; a compressor main body housed within the package; an oil recovery device housed within the package that recovers oil separated from discharge air discharged from the compressor main body; an oil level gauge installed on an outer wall of the oil recovery device within the package for checking the oil level position of the oil stored in the oil recovery device; and an imaging unit housed within the package that acquires an image of the oil level gauge, and that is capable of outputting information regarding the oil level position based on the image to the outside of the package.

[0007] Since information about the oil level based on the image of the oil level gauge acquired by the imaging unit can be output to the outside of the package, there is no need to remove the cover that constitutes the package to visually check the oil level. In other words, it is possible to check whether the appropriate amount of oil is stored in the oil recovery device (whether oil needs to be replenished) without removing the cover of the package. In this respect, the package-type compressor of this aspect makes it easy to inspect the oil recovery device.

[0008] The information regarding the oil level position may be an image of the oil level gauge acquired by the imaging unit.

[0009] The information regarding the oil level position may be an image of the oil level position processed from an image of the oil level gauge acquired by the imaging unit.

[0010] The information regarding the oil level position may be in which of a plurality of sections defined by the upper limit and lower limit positions of the oil level gauge the oil level position obtained from the image of the oil level gauge acquired by the imaging unit is located.

[0011] The package-type compressor may be provided with a display unit on the outside of the package that displays information about the oil level position.

[0012] The package-type compressor may include a communication unit that transmits information about the oil level position to an external device via a communication line.

[0013] The packaged compressor may be equipped with a control unit that detects the oil level position from the image of the oil level gauge acquired by the imaging unit, and determines whether the detected oil level position exceeds the upper limit position of the oil level gauge, determines whether the detected oil level position is below the lower limit position, and determines whether a change in the detected oil level position is equal to or greater than a predetermined value, and an alarm unit that alerts when any of the determinations is met.

[0014] With this configuration, the alarm unit can automatically notify of an excess of oil stored in the oil recovery device, a shortage of oil due to oil leakage, etc., and abnormalities in the operation of the compressor body or the oil recovery device.

[0015] The control unit may determine whether the detected oil level position exceeds the upper limit position and whether the detected oil level position falls below the lower limit position during load operation of the compressor main body, and may also determine whether the change in the detected oil level position is greater than or equal to a predetermined value during load operation and no-load operation.

[0016] The control unit may further determine whether the oil separation performance of the oil separator is equal to or greater than a predetermined value, and the notification unit may notify that the determination is established.

[0017] According to the present disclosure, inspection of the oil recovery device in a package-type compressor equipped with an oil level gauge for the oil recovery device can be simplified.

[0018] FIG. 1 is a perspective view showing the appearance of a packaged compressor according to a first embodiment of the present disclosure. FIG. 2 is a schematic view of a compressor main body and an oil recovery unit according to the first embodiment. FIG. 3 is a schematic view showing a main portion of the packaged compressor according to the first embodiment. FIG. 4 is a partial perspective view of the oil recovery unit. FIG. 5 is a partial front view of the oil recovery unit. FIG. 6 is a flowchart for explaining an abnormality detection process. FIG. 7 is a schematic view showing a main portion of a first modified example of the packaged compressor according to the first embodiment. FIG. 8 is a schematic view showing a main portion of a second modified example of the packaged compressor according to the first embodiment. FIG. 9 is a schematic view showing a main portion of a third modified example of the packaged compressor according to the first embodiment.

[0019] Next, embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0020] 1 and 2 , in a package-type compressor 1 (hereinafter simply referred to as a compressor) according to an embodiment of the present disclosure, the components constituting the compressor, including a compressor main body 2, which is an oil-cooled compressor, and an oil recovery unit 3, are housed in a package 4. The package 4 is provided with an intake port and an exhaust port (not shown).

[0021] 2, the compressor body 2 in this embodiment has an inlet 2a and a discharge port 2b that communicate with a rotor chamber that houses a pair of male and female rotors (rotatably driven by a motor 5). Air is sucked in from the inlet 2a via the intake port (not shown) and compressed in the rotor chamber, and then discharged from the discharge port 2b. The discharge port 2b of the compressor body 2 is connected to the oil recovery device 3 via a discharge flow path 6.

[0022] The compressed air (discharge air) discharged from the discharge port 2b flows into the oil recovery device 3 through the discharge flow path 6. In the oil recovery device 3, oil is separated from the discharge air by centrifugal force caused by the swirling compressed air and by an oil separator (not shown), and is temporarily stored in an oil sump at the bottom. The compressed air from which the oil has been separated is sent from the oil recovery device 3 to the demand side via the supply flow path 7 and an exhaust port (not shown).

[0023] The lubricating oil stored in the oil reservoir of the oil recovery device 3 flows to the compressor body 2 through the oil supply flow path 8 due to the pressure difference between the oil recovery device 3 and the compressor body 2 (suction port 2a).

[0024] 2, 4, and 5, an oil level gauge 11 is installed on the outer wall 3a of the oil recovery device 3 housed in the package 4 as described above, for checking the liquid level of the oil stored in the oil recovery device 3. In other words, the oil level gauge 11 is also housed in the package 4.

[0025] The oil level gauge 11 in this embodiment includes an upper fluid coupling 11a and a lower fluid coupling 11b attached to the upper connecting hole 3b and the lower connecting hole 3c of the oil recovery device 3, respectively, and a transparent tube 11c (a square tube in this embodiment) made of a transparent material such as glass. The upper and lower ends of the flow path in the transparent tube 11c are fluidly connected to the inside of the oil recovery device 3 via the upper fluid coupling 11a and the lower fluid coupling 11b. The oil level of the oil stored in the oil recovery device 3 can be confirmed by the liquid level of the oil introduced into the transparent tube 11c.

[0026] 4 and 5, an upper limit position 11d and a lower limit position 11e are displayed as visible lines on the transparent tube 11c. The upper limit position 11d and the lower limit position 11e correspond to the upper and lower limits of the oil level position in the oil recovery device 3 at which the normal operation of the compressor body 11 can be ensured.

[0027] The oil level gauge 11 may be a dial oil level gauge, that is, a type in which a pointer rotates on a scale plate in conjunction with the rise and fall of a float floating on the oil surface of the oil recovery device 3. The type of the oil level gauge 11 is not particularly limited as long as it allows the oil level in the oil recovery device 3 to be visually confirmed from outside the oil recovery device 3.

[0028] A visible light camera 12 that photographs the oil level gauge 11, particularly the transparent tube 11c, and acquires the image is housed within the package 4. In this embodiment, the visible light camera 12 is an example of an imaging unit that acquires the image of the oil level gauge 11, and although the visible light camera 12 is capable of color photography, it may also be capable of only monochrome photography.

[0029] In this embodiment, the visible light camera 12 is fixed to the upper part of a bracket 13, the lower part of which is fixed to the base 4a of the package 4. The visible light camera 12 may be held by a member other than the base 4a.

[0030] 2 and 3, a light 14 is housed in the package 4, which irradiates illumination light onto at least the portion of the oil level gauge 11 that is within the photographing range of the visible light camera 12, particularly the transparent tube 11c. The light 14 may be held on the base 4a of the package 4, like the visible light camera 12, or may be held on another member.

[0031] 2 and 3, a control unit 21 is housed within the package 4. Furthermore, referring to Fig. 1 in addition to Figs. 2 and 3, an input unit 23 for an operator to input instructions, settings, etc. to the control unit 21, and a display unit 24 which is a display that visually displays information from the control unit 21 (particularly, information relating to the oil level position as will be described later) are provided on the outside of the package 4.

[0032] The control unit 21 controls the devices constituting the package-type compressor 1, including the motor 5 for driving the compressor main body 2, based on inputs from various sensors and the input unit 23. Furthermore, as will be described later, the control unit 21 generates and outputs information relating to the oil level position on the oil level gauge 11 based on an image of the oil level gauge 11 acquired by the visible light camera 12. Note that a separate board (control unit) from the control unit 21 may be provided for generating and outputting information relating to the oil level position on the oil level gauge 11 based on the image of the oil level gauge 11 acquired by the visible light camera 12.

[0033] 3, the control unit 21 in this embodiment includes a processing unit 21A, a memory unit 21B, communication units 21C and 21D, and a power supply unit 21E. The processing unit 21A processes images of the oil level gauge 11 acquired by the visible light camera 12 based on programs and data stored in the memory unit 21B. The processing unit 21A can be constructed using a CPU or the like, and the memory unit 21B can be constructed using a ROM, RAM, or the like. The communication unit 21C communicates with the visible light camera 12 and the light 14. The power supply unit 21E supplies power to the visible light camera 12 and the light 14. The communication unit 21D communicates with an external terminal 26 via a communication line 25.

[0034] The communication line 25 may include a public line such as the Internet. The communication line 25 may be a wireless line in part or in whole, or may be a wired line. The communication line 25 functions as a connection called MtoM (Machine-to-Machine), which allows devices to directly exchange information with each other.

[0035] The external terminal 26 includes a display unit 26A that is a display that visually displays information from the control unit 21 (particularly, information related to the oil level position, as will be described later), and an alarm 26B that is a buzzer that sounds under the control of the control unit 21. Examples of the external terminal 26 include a personal computer and a portable information terminal (including a smartphone).

[0036] The control unit 21 outputs information about the oil level position based on the image of the oil level gauge 11 acquired by the visible light camera 12 to the outside of the package 4, more specifically, to a display unit 24 provided outside the package 4 and a display unit 26A of the external terminal 26, and the input information is displayed on the displays 24 and 26A. Since information about the oil level position based on the image of the oil level gauge 11 acquired by the visible light camera 12 can be output to the outside of the package 4 in this manner, it is not necessary to remove the cover constituting the package 4 to visually check the oil level position. In other words, it is possible to check whether an appropriate amount of oil is stored in the oil recovery device 3 (whether oil needs to be replenished) without removing the cover of the package 4. In this respect, the package-type compressor 1 of this embodiment facilitates inspection of the oil recovery device 3. Furthermore, simplifying inspection of the oil recovery device 3 in this embodiment does not require a design change to the oil recovery device 3, which is a pressure vessel. Furthermore, the simplification of inspection of the oil recovery device 3 in this embodiment can be realized as an additional function of an existing package-type compressor, as long as there is space within the package 4 to install the visible light camera 12 and the light 14 and the control unit 21 can communicate with the visible light camera 12.

[0037] The information regarding the oil level position based on the image of the oil level gauge 11 acquired by the visible light camera 12 may be the image of the oil level gauge 11 itself acquired by the visible light camera 12, an image of the oil level position generated by processing the image of the oil level gauge 11 acquired by the visible light camera 12, or information regarding which of the three sections defined by the upper limit position 11d and the lower limit position 11e the oil level position is in.

[0038] The image of the oil level gauge 11 captured by the visible light camera 12 is displayed on the display units 24, 26A, so that the oil level position can be monitored in real time without removing the cover of the package 4 and visually checking the oil level gauge 11. In particular, the image of the oil level gauge 11 is displayed on the display unit 26A of the external terminal 26, so that the oil level position can be monitored in real time remotely, without going to the site where the package-type compressor 1 is installed.

[0039] The image of the oil level position obtained by processing the image of the oil level gauge 11 acquired by the visible light camera 12 is, for example, obtained by grayscaling the image acquired by the visible light camera 12 and detecting changes in brightness of the image as edges (contours). In this case, too, the oil level position can be monitored in real time without removing the cover of the package 4, and the oil level position can be monitored in real time remotely using the display unit 26A of the external terminal 26.

[0040] The oil level in one of the three sections defined by the upper limit position 11d and the lower limit position 11e (i.e., whether the oil level is above the upper limit position 11d, below the lower limit position 11e, or between the upper limit position 11d and the lower limit position 11e) can be detected, for example, as follows: The image captured by the visible light camera 12 is grayscaled, and changes in brightness in the image are detected as edges (contours). Based on this grayscale, the oil level, the upper limit position 11d, and the lower limit position 11e are detected. This detection determines which of the three sections the oil level is in. When the section in which the oil level is in is displayed on the display units 24 and 26A in this way, the amount of data transferred via M2M communication, i.e., the amount of data transmitted from the control unit 21 via the communication line 25, can be reduced compared to transmitting an image. In this case, the oil level can be monitored in real time without removing the cover of the package 4, and the oil level can be monitored in real time remotely using the display unit 26A of the external terminal 26.

[0041] The oil level position among the three divisions can be displayed, for example, by a two-digit binary number. For example, if the first digit is "Is the oil level position below the upper limit position 11d?" and the second digit is "Is the oil level position above the lower limit position 11e?" and "Yes" is "1" and "No" is "0" for each digit, then the oil level position above the upper limit position 11d can be expressed as "01," the oil level position between the upper limit position 11d and the lower limit position 11e as "11," and the oil level position below the lower limit position 11e as "10," thereby expressing which division the oil level position is in. By transmitting only the oil level position obtained by image processing in this way, the transfer volume can be reduced to a few bytes.

[0042] Information about the oil level position based on the image of the oil level gauge 11 acquired by the visible light camera 12 may include a level representation of the oil level position. An example will be described below. First, the image acquired by the visible light camera 12 is grayscaled, and changes in the brightness of the image are detected as edges (contours). Based on this, the oil level position, upper limit position 11d, and lower limit position 11e are detected. Next, the distance between the upper limit position 11d and the lower limit position 11e is determined to be one of 10 equal levels (the lower limit position 11e is level 0, and the upper limit position 11d is level 10). If the distance between the upper limit position 11d and the lower limit position 11e is 100 pixels, the oil level position can be determined to be level 4 if it is located 35 pixels above the lower limit position 11e.

[0043] The control unit 21 of this embodiment executes the abnormality detection process shown in FIG. 6 . In the following description, the specific content of the process executed at each step will not be repeated if it has already been explained. First, an image of the oil level gauge 11 is captured by the visible light camera 12 (step S1), and the oil level is detected based on this image (step S2). Next, it is determined whether the oil level exceeds the upper limit position 11d, i.e., whether the amount of oil filled is excessive (step S4). If it does, a notification process (step S3) is executed. Specific details of the notification process will be described later. Next, it is determined whether the oil level is below the lower limit position 11e, i.e., whether the amount of oil filled is insufficient (step S5). If it does, a notification process (step S3) is executed. Furthermore, it is determined whether the change in the oil level position is within the normal range, more specifically, whether the change in the level of the oil level position is equal to or greater than a reference value, i.e., whether there is a possibility of an oil leak (step S6). If it is determined that the change is not within the normal range, i.e., an abnormality exists, a notification process (step S3) is executed. In step S6, assuming that a change of one level or more in 30 seconds is abnormal, for example, the data on the oil level position is held for 30 seconds, and if there is a change of one level (reference value) or more compared with the data from 30 seconds ago, it is determined that the oil level is not within the normal range. Furthermore, it is determined whether the oil separation performance of the oil recovery device 3 is within the normal range, that is, whether the oil separator element of the oil recovery device 3 needs to be replaced (step S7), and if it is determined that the oil level is not within the normal range, that is, that there is an abnormality, a notification process (step S3) is executed. The oil separation performance is evaluated based on the operating conditions (load factor, pressure, operating time, etc.) and the theoretical value of the oil contained in the discharge air discharged from the compressor main body 2 (for example, 0.002 cc / m 3 ) to determine the theoretical value of the level drop of the oil level, and if the change in the level of the oil level position exceeds this theoretical value (if the amount of oil contained in the discharge air discharged from the compressor main body 2 exceeds the theoretical value), it is determined that the change is not within the normal range.

[0044] In the notification process of step S3, the details of the abnormality detected in steps S4 to S7 are displayed on the display units 24, 26A. In this notification process, an alarm (for example, a buzzer that sounds under the control of the control unit 21) provided in the package-type compressor 1 or an alarm 26B of the external terminal 26 may be sounded in addition to or instead of the display on the display units 24, 26A.

[0045] During no-load operation, it may be normal for the oil level position to be not between the upper limit position 11d and the lower limit position 11e. Therefore, steps S4 and S5 may not be executed during no-load operation of the compressor main body 2, but may be executed only during loaded operation. Furthermore, steps S6 and S7 may be executed while the compressor is operating, that is, during loaded operation and no-load operation. That is, during loaded operation, the control unit may determine whether the detected oil level position is above the upper limit position 11d and whether the detected oil level position is below the lower limit position 11e, and may determine whether the change in the detected oil level position is equal to or greater than a predetermined value during loaded operation and no-load operation.

[0046] The output of information regarding the oil level position based on the image of the oil level gauge 11 acquired by the visible light camera 12 and the abnormality detection process as shown in Fig. 6 may be performed continuously using real-time video, or may be performed by capturing still images at appropriate time intervals and comparing these still images. Since the oil level position does not fluctuate significantly unless there is an abnormality in the compressor main body 2 or the oil recovery device 3, from the viewpoint of energy conservation, the process may be performed continuously for a certain period of time after the compressor main body 2 is started, and then at certain time intervals during continuous operation (progress monitoring).

[0047] 7 to 9 show modifications of the first embodiment. In these drawings, the same or similar elements are denoted by the same reference numerals. Furthermore, configurations and functions of these modifications that are not specifically mentioned are the same as those of the first embodiment.

[0048] In the modification shown in Fig. 7, power is supplied to the light 14 by a Peltier element 51 attached to the oil recovery device 3. This configuration, in other words, a configuration in which the power supplied to the light 14 is supplemented by power generated by the compressor as a heat source, improves energy conservation.

[0049] In the modified example shown in Fig. 8, an infrared camera 52 is used instead of the visible light camera 12 (see Fig. 3, for example). This configuration eliminates the need for the light 14 (see Fig. 3, for example), thereby improving energy conservation and simplifying the device configuration.

[0050] 9, an intelligent camera 53 is used instead of the visible light camera 12 (see, for example, FIG. 3). The intelligent camera 53 outputs information about the oil level position based on the image of the oil level gauge 11 to an external terminal, which was performed by the control unit 21 in the first embodiment, and also performs anomaly detection processing as shown in FIG.

[0051] This application claims priority based on Japanese Patent Application No. 2023-121966, filed July 26, 2023. Japanese Patent Application No. 2023-121966 is incorporated herein by reference.

[0052] DESCRIPTION OF SYMBOLS 1 Package type compressor 2 Compressor body 2a Suction port 2b Discharge port 3 Oil recovery container 3a Outer wall 3b Upper connection hole 3c Lower connection hole 4 Package 4a Base 5 Motor 6 Discharge flow path 7 Supply flow path 8 Oil supply flow path 11 Oil level gauge 11a Upper fluid coupling 11b Lower fluid coupling 11c Transparent tube 11d Upper limit position 11e Lower limit position 12 Visible light camera (imaging unit) 13 Bracket 14 Light 21 Control unit 21A Processing unit 21B Memory unit 21C, 21D Communication unit 21E Power supply unit 22 Alarm 23 Input unit 24 Display unit 25 Communication line 26 External terminal 26A Display unit 26B Alarm 51 Peltier element 52 Infrared camera 53 Intelligent camera (imaging unit)

Claims

1. A package-type compressor comprising: a package; a compressor body contained within the package; an oil recovery device contained within the package for recovering oil separated from the discharge air discharged from the compressor body; an oil level gauge installed on an outer wall of the oil recovery device within the package for checking the oil level position of the oil stored in the oil recovery device; and an imaging unit contained within the package for acquiring an image of the oil level gauge, and capable of outputting information regarding the oil level position based on the image to the outside of the package.

2. The package-type compressor according to claim 1, wherein the information regarding the oil level position is an image of the oil level gauge acquired by the imaging unit.

3. A package type compressor as described in claim 1, wherein the information regarding the oil level position is an image of the oil level position processed from an image of the oil level gauge acquired by the imaging unit.

4. A package type compressor as described in claim 1, wherein the information regarding the oil level position is whether the oil level position obtained from the image of the oil level gauge acquired by the imaging unit is in one of a plurality of sections defined by upper and lower limit positions of the oil level gauge.

5. A package type compressor according to any one of claims 1 to 4, further comprising a display unit provided outside the package for displaying information relating to the oil level position.

6. A package type compressor according to any one of claims 1 to 4, further comprising a communication unit that transmits information relating to the oil level position to an external device via a communication line.

7. A package type compressor as described in claim 1, comprising: a control unit that detects an oil level position from an image of the oil level gauge acquired by the imaging unit, and determines whether the detected oil level position exceeds an upper limit position of the oil level gauge, determines whether the detected oil level position falls below a lower limit position, and determines whether a change in the detected oil level position is equal to or greater than a predetermined value; and an alarm unit that notifies that any of the determinations is established.

8. The package type compressor according to claim 7, wherein the control unit, during load operation of the compressor body, determines whether the detected oil level position exceeds the upper limit position and determines whether the detected oil level position falls below the lower limit position, and determines whether the change in the detected oil level position is equal to or greater than a predetermined value during load operation and no-load operation.

9. The package-type compressor according to claim 7, wherein the control unit further executes a determination as to whether the oil separation performance of the oil separator is equal to or greater than a predetermined value, and the notification unit notifies that the determination is established.

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