Claw compressor and abnormality determination method for claw compressor

Abstract

To properly determine an abnormal state of any of a first rotor connected to a drive shaft, a second rotor connected to a driven shaft, and a driven bearing part supporting the driven shaft.SOLUTION: The male rotor 24, the drive shaft 32 coupled to the male rotor 24, the rear end bearing 38 that rotatably supports the drive shaft 32, the drive unit 50 that generates a driving force for rotating the drive shaft 32, the female rotor 26, the driven shaft 42 coupled to the female rotor 26, the rear end bearing 48 that rotatably supports the driven shaft 42, the driving force transmission unit that transmits the driving force from the drive shaft 32 to the driven shaft 42, and the measuring unit 60 that measures the amount of displacement of the driven shaft 42 at the second end 42a of the driven shaft 42 opposite to the first end 42b; And a determination unit 70 that determines an abnormal state of any one of the male rotor 24, the female rotor 26, the tip end side bearing 47, and the rear end side bearing 48 based on the displacement amount measured by the measurement unit 60.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a claw compressor and a method for determining an abnormality in a claw compressor. [Background technology]

[0002] A claw compressor has a pair of rotors with hook-shaped claws formed inside a housing that forms a compression chamber. The rotors rotate at the same speed in opposite directions without contact while maintaining a predetermined clearance, forming a compression pocket between the two rotors, which discharges the fluid compressed in the compression pocket. Such claw compressors are often used primarily as vacuum pumps and blowers (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6845596 Summary of the Invention [Problem to be solved by the invention]

[0004] When a steam generation heat pump is used as an alternative to a boiler and the generated steam is compressed by a claw compressor, the internal temperature becomes higher and the pressure difference between the suction pressure and the discharge pressure becomes larger than in a vacuum pump or blower. In such a claw compressor, the rotating shaft that rotates the two rotors may become misaligned due to temperature distribution within the machine or assembly errors. In this case, the two rotors may come into contact with the parts that form the compression chamber, or the rotors may come into contact with each other, which may damage the bearings that support the rotors or the rotating shaft.

[0005] The present disclosure has been made in consideration of the above circumstances, and aims to provide a claw compressor and an abnormality determination method for a claw compressor that can appropriately determine an abnormal state of any of the first rotor connected to the drive shaft, the second rotor connected to the driven shaft, and the driven bearing portion that supports the driven shaft. [Means for solving the problem]

[0006] In order to solve the above problems, the claw compressor of the present disclosure employs the following measures. A claw compressor according to one aspect of the present disclosure includes a first rotor having a plurality of first claws protruding in a radial direction, a drive shaft connected to the first rotor and extending along a first axis, a drive bearing unit rotatably supporting the drive shaft, a drive unit connected to the drive shaft and generating a driving force to rotate the drive shaft, a second rotor having a plurality of second claws protruding in the radial direction, a driven shaft connected to the second rotor and extending along a second axis parallel to the first axis, and a driven bearing unit rotatably supporting the driven shaft, a compression section that forms a compression chamber that houses the first rotor and the second rotor; a measurement section that measures the amount of displacement of the driven shaft in the radial direction perpendicular to the first axis and the second axis at a second end of the driven shaft opposite to a first end connected to the second rotor; and a determination section that determines an abnormal state of any of the first rotor, the second rotor, and the driven bearing section based on the amount of displacement measured by the measurement section.

[0007] In a method for determining an abnormality of a claw compressor according to one aspect of the present disclosure, the claw compressor includes a first rotor having a plurality of first claw portions protruding in a radial direction, a drive shaft connected to the first rotor and extending along a first axis, a drive bearing portion rotatably supporting the drive shaft, a drive portion connected to the drive shaft and generating a drive force for rotating the drive shaft, a second rotor having a plurality of second claw portions protruding in the radial direction, a driven shaft connected to the second rotor and extending along a second axis parallel to the first axis, a driven bearing portion rotatably supporting the driven shaft, and the drive portion. the first rotor and the second rotor at a second end of the driven shaft opposite to a first end connected to the second rotor; and a determining step of determining whether any of the first rotor, the second rotor, and the driven bearing is in an abnormal state based on the displacement measured in the measuring step. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to provide a claw compressor and a method for determining an abnormality in a claw compressor that can appropriately determine an abnormal state in any of the first rotor connected to the drive shaft, the second rotor connected to the driven shaft, and the driven bearing portion that supports the driven shaft. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of a claw compressor according to an embodiment of the present disclosure. [Figure 2] 2 is a cross-sectional view of the claw compressor shown in FIG. 1 taken along the line AA. [Figure 3] FIG. 2 is a front view of the claw compressor shown in FIG. [Figure 4] 10 is a graph showing changes in the displacement amount of the driven shaft measured by the measuring unit. [Figure 5]3 is a flowchart showing a method for determining an abnormal state of the claw compressor according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] An embodiment of the present disclosure will be described below with reference to the drawings. Fig. 1 is a perspective view showing a claw compressor 1 according to an embodiment of the present disclosure. As shown in Fig. 1, the claw compressor 1 includes a compression section 3 that defines a compression chamber therein, and a gear section 5 that houses a first timing gear 39 and a second timing gear 49. The compression section 3 is formed by a front case 7 and a main case 9, and the gear section 5 is formed by the main case 9 and a gear case 11. The claw compressor 1 is installed upright on an installation surface using, for example, four legs 12.

[0011] The compression section 3 has an intake port 13 for drawing in steam (fluid) and an outlet port 15 for discharging the steam after compression. The steam is, for example, water vapor. The drawn steam may be under negative or positive pressure.

[0012] Fig. 2 is a cross-sectional view of the claw compressor 1 shown in Fig. 1 taken along the line AA. As shown in Fig. 2, the compression unit 3 is configured so that a recess formed in the front end (one side end) of the main case 9 is sealed with the front case 7 to form a compression chamber 20 therein.

[0013] The main case 9 is a housing in which a recess 9A that houses the male rotor (first rotor) 24 and the female rotor (second rotor) 26 is formed at the end on the front case 7 side. The front case 7 is a plate-shaped member that is attached to the main case 9 so as to seal the recess 9A. The front case 7, together with the recess 9A, forms a compression chamber 20 that houses the male rotor 24 and the female rotor 26.

[0014] FIG. 3 is a front view of the claw compressor 1 shown in FIG. 3 shows the claw compressor 1 with the front case 7 removed from the main case 9. As shown in FIG. 3, the male rotor 24 has a pair of hook-shaped claw portions (first claw portions) 24a. The claw portions 24a protrude in a radial direction perpendicular to the first rotation axis O1 and are provided symmetrically about the first rotation axis O1. The male rotor 24 rotates counterclockwise in FIG. 3 (in the direction of arrow A1).

[0015] The female rotor 26 has a pair of hook-shaped claws (second claws) 26a. The claws 26a protrude in a radial direction perpendicular to the second rotation axis O2 and are provided symmetrically about the second rotation axis O2. The female rotor 26 rotates clockwise (in the direction of arrow A2) in FIG. 3. The rotation direction of the female rotor 26 is opposite to the rotation direction of the male rotor 24.

[0016] The claws 24a of the male rotor 24 and the claws 26a of the female rotor 26 are adapted to mesh without contacting each other. The male rotor 24 is formed with a recess (first recess) 24b that receives the claws 26a of the female rotor 26 during the compression stroke. The female rotor 26 is formed with a recess (second recess) 26b that receives the claws 24a of the male rotor 24 during the compression stroke. The compressed steam is discharged from a substantially triangular discharge port 15 that is formed in the front case 7 (not shown).

[0017] 3, the shape of compression chamber 20 is defined by the inner wall 9a of main case 9, and has a cross-sectional shape formed by partially overlapping two circles, one centered on first rotational axis O1 and the other centered on second rotational axis O2. The tips of claws 24a, 26a of rotors 24, 26 run along inner wall 9a of main case 9 with a predetermined clearance.

[0018] As shown in Fig. 2, the male rotor 24 is fastened to the drive shaft 32 by a first bolt 31. As shown in Fig. 2, the first bolt 31 is screwed onto the drive shaft 32 with the axis of the first bolt 31 coinciding with the first rotation axis O1. A fastening structure is configured with the center of the male rotor 24 sandwiched between the tip surface of the drive shaft 32 and the head of the first bolt 31. The head of the first bolt 31 is housed in a cylindrical recess 24c formed in the center of the male rotor 24.

[0019] The female rotor 26 is fastened to the driven shaft 42 by a second bolt 41. The second bolt 41 is screwed onto the driven shaft 42 with the axis of the second bolt 41 coinciding with the second rotation axis O2. The driven shaft 42 is disposed parallel to the drive shaft 32. That is, the first rotation axis O1 and the second rotation axis O2 are parallel to each other.

[0020] A fastening structure is configured with the center of the female rotor 26 sandwiched between the tip end surface of the driven shaft 42 and the head of the second bolt 41. The head of the second bolt 41 is housed in a cylindrical recess 26c formed in the center of the female rotor 26.

[0021] The drive shaft 32 that supports the male rotor 24 has its tip located within the compression chamber 20 and its rear end connected to a drive unit 50. The drive unit 50 is connected to the drive shaft 32 and generates a driving force that rotates the drive shaft 32 about the first rotation axis O1, and an electric motor is used, for example. The drive shaft 32 rotates about the first rotation axis O1, thereby rotating the male rotor 24 within the compression chamber 20. The drive shaft 32 is rotatably supported at two locations: a tip-side bearing (drive bearing portion) 37 and a rear-side bearing (drive bearing portion) 38.

[0022] The front end bearing 37 is provided in the main case 9 and is, for example, a double-row ball bearing. The rear end bearing 38 is located rearward of the front end bearing 37 and is provided in the gear case 11. A first timing gear (driving force transmission part) 39 is fixed to the drive shaft 32 between the front end bearing 37 and the rear end bearing 38. The first timing gear 39 is, for example, a spur gear, and rotates together with the drive shaft 32 about a first rotation axis O1.

[0023] The first timing gear 39 is provided in the gear unit 5 and is housed in a gear chamber 21 formed between the rear end of the main case 9 and the front end of the gear case 11. The main case 9 and the gear case 11 are attached liquid-tight via an O-ring 23 so as to seal in the lubricating oil in the gear chamber 21.

[0024] The driven shaft 42 that supports the female rotor 26 has a front end located within the compression chamber 20 and a rear end that terminates in the gear case 11. The driven shaft 42 rotates about the second rotation axis O2, causing the female rotor 26 to rotate within the compression chamber 20. The driven shaft 42 is rotatably supported at two locations: a front end bearing (driven bearing portion) 47 and a rear end bearing (driven bearing portion) 48. The front end bearing 47 is provided in the main case 9 and is, for example, a double-row ball bearing. The rear end bearing 48 is located rearward of the front end bearing 47 and is provided in the gear case 11.

[0025] A second timing gear (driving force transmission portion) 49 is fixed to the driven shaft 42 between a front end bearing 47 and a rear end bearing 48. The second timing gear 49 is, for example, a spur gear, and rotates around the second rotation axis O2 together with the driven shaft 42. The second timing gear 49 is provided in the gear portion 5 and is housed in the gear chamber 21.

[0026] The second timing gear 49 is in mesh with the first timing gear 39, and receives the driving force from the first timing gear 39. The first timing gear 39 and the second timing gear 49 transmit the driving force, with which the drive unit 50 rotates the drive shaft 32, from the drive shaft 32 to the driven shaft 42, causing the driven shaft 42 to rotate in the opposite direction to the drive shaft 32.

[0027] The claw compressor 1 configured as described above operates as follows: The drive shaft 32 is rotationally driven by the drive unit 50, causing the male rotor 24 to rotate within the compression chamber 20. The second timing gear 49, to which a rotational driving force is transmitted from the first timing gear 39, which rotates together with the drive shaft 32, causes the driven shaft 42 to rotate, causing the female rotor 26 to rotate within the compression chamber 20.

[0028] As the male rotor 24 and female rotor 26 rotate within the compression chamber 20, steam is drawn in through the suction port 13. The male rotor 24 rotates counterclockwise in FIG. 3 (in the direction of arrow A1), taking in steam into the compression pockets formed by the claws 24a and moving it downward along the outer periphery of the compression chamber 20. The female rotor 26 rotates clockwise in FIG. 3 (in the direction of arrow A2), taking in steam into the compression pockets formed by the claws 26a and moving it downward along the outer periphery of the compression chamber 20.

[0029] The compression pocket formed by the male rotor 24 and the compression pocket formed by the female rotor 26 then join together in the center of the lower part of the compression chamber 20, and in this combined compression pocket, the claws 24a of the male rotor 24 enter the recesses 26b of the female rotor 26 to compress the steam. The compressed steam is discharged to the outside from the discharge port 15.

[0030] Next, we will explain a method for measuring the displacement of the driven shaft 42 and determining whether any of the male rotor 24, female rotor 26, front-end bearing 47, and rear-end bearing 48 is in an abnormal state. Figure 4 is a graph showing changes in the displacement of the driven shaft 42 measured by the measuring unit 60.

[0031] 2, the claw compressor 1 of this embodiment has a measuring unit 60, a determining unit 70, and a control unit 80. The measuring unit 60 is a device that measures the amount of displacement of the driven shaft 42 in the radial direction perpendicular to the first rotation axis O1 and the second rotation axis O2 at a second end 42b opposite to a first end 42a of the driven shaft 42 that is connected to the female rotor 26.

[0032] The measuring unit 60 measures the displacement D of the driven shaft 42 in the direction along the measurement axis O3 perpendicular to the first rotation axis O1 and the second rotation axis O2, based on a position at which reflected light of laser light irradiated from the measurement position 61 along the measurement axis O3 perpendicular to the second rotation axis O2 is received. As shown in Fig. 2, the measuring unit 60 is fixed via a fixing member 62 to the gear case (casing) 11 to which the rear end bearing 48 is attached.

[0033] The measurement unit 60 calculates the distance L on the measurement axis O3 from the measurement position 61 to the driven shaft 42, and measures the difference between the distance L and a reference distance as the displacement D. Here, the reference distance is the distance on the measurement axis O3 from the measurement position 61 to the driven shaft 42 in a stopped state in which there are no abnormalities in any of the male rotor 24, female rotor 26, front end bearing 47, and rear end bearing 48 and the claw compressor 1 is stopped.

[0034] If the distance L on the measurement axis O3 from the measurement position 61 to the driven shaft 42 matches the reference distance, the measurement unit 60 measures the displacement D to be 0. If the distance L on the measurement axis O3 from the measurement position 61 to the driven shaft 42 is shorter than the reference distance, the measurement unit 60 measures the displacement D as a positive value obtained by subtracting the distance L from the reference distance. If the distance L on the measurement axis O3 from the measurement position 61 to the driven shaft 42 is longer than the reference distance, the measurement unit 60 measures the displacement D as a negative value obtained by subtracting the distance L from the reference distance.

[0035] The determination unit 70 is a device that determines whether any of the male rotor 24, female rotor 26, front end bearing 47, and rear end bearing 48 is in an abnormal state based on the displacement D measured by the measurement unit 60. When the displacement D of the second end 42b of the driven shaft 42 in a stopped state in which steam is not compressed in the compression chamber 20 is set to 0, and the displacement D in the direction away from the drive shaft 32 exceeds a first predetermined displacement D1, the determination unit 70 determines that at least one of the male rotor 24 and the female rotor 26 is in a first abnormal state, that is, an abnormal state.

[0036] 4, when at least one of the male rotor 24 and the female rotor 26 is abnormal, the displacement of the driven shaft 42 exceeds D1 at time t1, and the determining unit 70 determines that the first abnormal state exists. For example, when a foreign object becomes caught between the female rotor 26 and the inner wall 9a of the main case 9, or when an excessive load is applied to the female rotor 26 when liquefied steam is compressed in the compression chamber 20, the driven shaft 42 is displaced in a direction away from the drive shaft 32, and when the displacement becomes excessive, the displacement exceeds D1.

[0037] In addition, when the displacement amount D of the second end 42b of the driven shaft 42 in a stopped state in which steam is not compressed in the compression chamber 20 is set to 0, if the displacement amount D in the direction away from the drive shaft 32 exceeds a second predetermined displacement amount D2 that is larger than the first predetermined displacement amount D1, the judgment unit 70 judges that a second abnormal state has occurred in which at least one of the front end bearing 47 and the rear end bearing 48 is abnormal.

[0038] 4, when at least one of the front-end bearing 47 and the rear-end bearing 48 is abnormal, the amount of displacement of the driven shaft 42 exceeds D2 at time t2, and the determining unit 70 determines that the second abnormal state exists. For example, if the front-end bearing 47 and the rear-end bearing 48 are damaged and the driven shaft 42 cannot be maintained on the second rotation axis O2, the driven shaft 42 will be displaced in a direction away from the drive shaft 32, and if the amount of displacement becomes excessive, the amount of displacement will exceed D2.

[0039] In addition, when the displacement amount D of the second end 42b of the driven shaft 42 in a stopped state in which steam is not compressed in the compression chamber 20 is set to 0, if the displacement amount D in the direction toward the drive shaft 32 exceeds a third predetermined displacement amount D3, the judgment unit 70 judges that a third abnormal state has occurred in which at least one of the front end bearing 47 and the rear end bearing 48 is abnormal.

[0040] The control unit 80 is a device that controls the drive unit 50 based on the determination result of the determination unit 70. When the determination unit 70 determines that the claw compressor 1 is in the first abnormal state, the second abnormal state, or the third abnormal state, the control unit 80 controls the drive unit 50 to stop the rotation of the drive shaft 32.

[0041] Next, a method for determining an abnormal state of the claw compressor 1 of this embodiment will be described below. Fig. 5 is a flowchart showing the method for determining an abnormal state of the claw compressor 1 of this embodiment. In step S101, the measuring unit 60 measures the radial displacement D of the driven shaft 42 perpendicular to the first rotation axis O1 and the second rotation axis O2 at the second end 42b opposite to the first end 42a connected to the female rotor 26 of the driven shaft 42.

[0042] In step S102, the judgment unit 70 judges whether the displacement amount D in the direction away from the drive shaft 32 exceeds a first predetermined displacement amount D1, and if it does, it judges that a first abnormal state has occurred in which at least one of the male rotor 24 and the female rotor 26 is abnormal, and proceeds to step S103.

[0043] In step S103, the judgment unit 70 judges whether the displacement amount D in the direction away from the drive shaft 32 exceeds a second predetermined displacement amount D2, and if it does, judges that a second abnormal state has occurred in which at least one of the front end bearing 47 and the rear end bearing 48 is abnormal, and proceeds to step S105.

[0044] In step S104, the determination unit 70 issues a first warning indicating a first abnormal state to an external device, etc. The first warning is, for example, a warning indicating that at least one of the male rotor 24 and the female rotor 26 is abnormal, or a warning urging replacement of the internal devices of the compression chamber 20, including the male rotor 24 and the female rotor 26.

[0045] In step S105, the determination unit 70 issues a second warning indicating a second abnormal state to an external device, etc. The second warning is, for example, a warning indicating that at least one of the front end bearing 47 and the rear end bearing 48 is abnormal, or a warning urging replacement of at least one of the front end bearing 47 and the rear end bearing 48.

[0046] In step S106, the judgment unit 70 judges whether the displacement amount D in the direction approaching the drive shaft 32 exceeds a third predetermined displacement amount D3, and if it does, judges that a third abnormal state has occurred in which at least one of the front end bearing 47 and the rear end bearing 48 is abnormal, and proceeds to step S107.

[0047] In step S107, the determination unit 70 issues a third warning indicating a third abnormal state to an external device, etc. The third warning is, for example, a warning indicating that at least one of the front end bearing 47 and the rear end bearing 48 is abnormal, or a warning urging replacement of at least one of the front end bearing 47 and the rear end bearing 48.

[0048] After executing steps S104, S105, and S107, the control unit 80 controls the drive unit 50 to stop the rotation of the drive shaft 32 because the claw compressor 1 is in either the first abnormal state, the second abnormal state, or the third abnormal state.

[0049] On the other hand, if it is determined in step S106 that the third abnormal state is not present, the claw compressor 1 is not in any of the first, second, or third abnormal states, and therefore the processing of this flowchart is terminated without executing step S108.

[0050] The claw compressor 1 of this embodiment described above provides the following functions and effects.

[0051] According to the claw compressor 1 of this embodiment, in the compression chamber 20 accommodating the male rotor 24 and the female rotor 26, the male rotor 24 connected to the drive shaft 32 rotates about the first rotational axis O1, and the female rotor 26 connected to the driven shaft 42 rotates about the second rotational axis O2 in the opposite direction to the male rotor 24, and the meshing of the claws 24a and 26a compresses steam. When the steam is compressed, steam pressure acts on the first end 42a of the driven shaft 42 connected to the female rotor 26 in a radial direction perpendicular to the second rotational axis O2 and away from the first rotational axis O1.

[0052] According to the claw compressor 1 of this embodiment, the measurement unit 60 measures the displacement D of the driven shaft 42 in the radial direction perpendicular to the first rotation axis O1 and the second rotation axis O2 at the second end 42b opposite to the first end 42a of the driven shaft 42 connected to the female rotor 26, and the determination unit 70 determines whether any of the male rotor 24, female rotor 26, front end bearing 47, and rear end bearing 48 is in an abnormal state based on the displacement D. According to the claw compressor 1 of this embodiment, it is possible to appropriately determine whether any of the male rotor 24 connected to the drive shaft 32, the female rotor 26 connected to the driven shaft 42, the front end bearing 47, and the rear end bearing 48 is in an abnormal state.

[0053] According to the claw compressor 1 of this embodiment, if it is determined that any of the male rotor 24, female rotor 26, front end bearing 47, and rear end bearing 48 is in an abnormal state, the rotation of the drive shaft 32 and driven shaft 42 can be stopped and the claw compressor 1 can be brought to a stopped state.

[0054] According to the claw compressor 1 of this embodiment, when steam is compressed, steam pressure acts on the first end 42a of the driven shaft 42 connected to the female rotor 26 in a radial direction perpendicular to the second rotational axis O2 and away from the first rotational axis O1. Meanwhile, when steam is compressed, a force acts on the second end 42b of the driven shaft 42 in a radial direction perpendicular to the second rotational axis O2 and toward the first rotational axis O1. If the displacement D in the direction away from the drive shaft 32 exceeds the first predetermined displacement D1 despite the steam pressure acting on the second end 42b of the driven shaft 42 in a radial direction toward the first rotational axis O1 of the drive shaft 32, it can be determined that an abnormal state exists due to, for example, contact of at least one of the male rotor 24 and the female rotor 26 with another member.

[0055] According to the claw compressor 1 of this embodiment, if the displacement D in the direction away from the drive shaft 32 exceeds a second predetermined displacement D2 that is larger than the first predetermined displacement D1 even though a radial force acting on the second end 42b of the driven shaft 42 toward the first rotation axis O1 of the drive shaft 32 due to the pressure of the steam, it can be determined that an abnormal state exists due to damage to either the front end bearing 47 or the rear end bearing 48.

[0056] According to the claw compressor 1 of this embodiment, if the displacement amount D in the direction away from the drive shaft 32 exceeds the third predetermined displacement amount D3, it can be determined that an abnormal state exists due to damage to either the front end bearing 47 or the rear end bearing 48.

[0057] According to the claw compressor 1 of this embodiment, the measuring unit 60 is fixed to the gear case 11 to which the rear end bearing 48 is attached. Therefore, by fixing the measuring unit 60 to a location other than the gear case 11, it is possible to prevent problems such as vibrations of the compression chamber 20 resulting in errors in the displacement amount D.

[0058] The claw compressors described in the above-described embodiments can be understood, for example, as follows. A claw compressor according to a first aspect of the present disclosure includes a first rotor (24) having a plurality of first claws protruding in a radial direction, a drive shaft (32) connected to the first rotor and extending along a first axis (O1), drive bearings (37, 38) rotatably supporting the drive shaft, a drive unit (50) connected to the drive shaft and generating a driving force for rotating the drive shaft, a second rotor (26) having a plurality of second claws protruding in the radial direction, a driven shaft (42) connected to the second rotor and extending along a second axis (O2) parallel to the first axis, driven bearings (47, 48) rotatably supporting the driven shaft, and a front The driving force transmission unit (39, 49) transmits the driving force with which the driving unit rotates the drive shaft from the drive shaft to the driven shaft, causing the driven shaft to rotate in the opposite direction to the drive shaft; a compression unit (3) that forms a compression chamber (20) that accommodates the first rotor and the second rotor; a measurement unit (60) that measures the amount of displacement of the driven shaft in the radial direction perpendicular to the first axis and the second axis at a second end of the driven shaft opposite to the first end connected to the second rotor; and a determination unit (70) that determines an abnormal state of any of the first rotor, the second rotor, and the driven bearing unit based on the amount of displacement measured by the measurement unit.

[0059] In a claw compressor according to a first aspect of the present disclosure, in a compression chamber accommodating a first rotor and a second rotor, the first rotor connected to a drive shaft rotates about a first axis, and the second rotor connected to a driven shaft rotates about a second axis in the opposite direction to the first rotor, and fluid is compressed by meshing of the first claws with the second claws. When the fluid is compressed, fluid pressure acts on a first end of the driven shaft connected to the second rotor in a radial direction perpendicular to the second axis and away from the first axis.

[0060] According to the claw compressor of the first aspect of the present disclosure, the measurement unit measures the displacement of the driven shaft in the radial direction perpendicular to the first axis and the second axis at the second end of the driven shaft opposite to the first end connected to the second rotor, and the determination unit determines whether or not an abnormal state is present in any of the first rotor, the second rotor, or the driven bearing based on the displacement. The claw compressor of the first aspect of the present disclosure can appropriately determine whether or not an abnormal state is present in any of the first rotor connected to the drive shaft, the second rotor connected to the driven shaft, or the driven bearing that supports the driven shaft.

[0061] A claw compressor according to a second aspect of the present disclosure is the first aspect, further including the following configuration: the drive unit stops rotation of the drive shaft when the determination unit determines that any one of the first rotor, the second rotor, and the driven bearing unit is in an abnormal state.

[0062] According to the claw compressor of the second aspect of the present disclosure, if it is determined that any of the first rotor, the second rotor, and the driven bearing portion is in an abnormal state, the rotation of the drive shaft and the driven shaft can be stopped to put the claw compressor into a stopped state.

[0063] A claw compressor according to a third aspect of the present disclosure is the first or second aspect, further including the following configuration: That is, the determination unit determines that at least one of the first rotor and the second rotor is in an abnormal state when the displacement amount of the second end of the driven shaft in a direction away from the drive shaft exceeds a first predetermined displacement amount (D1) when the displacement amount of the second end of the driven shaft in a stopped state in which fluid is not compressed in the compression chamber is set to 0.

[0064] In the claw compressor according to the third aspect of the present disclosure, when a fluid is compressed, a fluid pressure acts on a first end of the driven shaft connected to the second rotor in a radial direction perpendicular to the second axis and away from the first axis. Meanwhile, when a fluid is compressed, a force acts on a second end of the driven shaft in a radial direction perpendicular to the second axis and toward the first axis. If the amount of displacement in the direction away from the drive shaft exceeds a first predetermined displacement amount despite the force acting on the second end of the driven shaft in a radial direction toward the first axis of the drive shaft due to the fluid pressure, it can be determined that at least one of the first rotor and the second rotor is in an abnormal state due to contact with another member or the like.

[0065] A claw compressor according to a fourth aspect of the present disclosure is the third aspect, and further includes the following configuration: The determination unit determines that the driven bearing unit is in an abnormal state when the displacement of the second end of the driven shaft in a direction away from the drive shaft exceeds a second predetermined displacement amount (D2) that is larger than the first predetermined displacement amount, when the displacement of the second end of the driven shaft in a stopped state in which fluid is not compressed in the compression chamber is set to 0.

[0066] According to the claw compressor of the fourth aspect of the present disclosure, if a radial force acting on the second end of the driven shaft toward the first axis of the drive shaft due to fluid pressure occurs, but the amount of displacement away from the drive shaft exceeds a second predetermined displacement amount that is greater than the first predetermined displacement amount, it can be determined that an abnormal state exists due to damage to the driven bearing portion or other causes.

[0067] A claw compressor according to a fifth aspect of the present disclosure is the first or second aspect, further including the following configuration: That is, the determination unit determines that the driven bearing unit is in an abnormal state when the displacement amount of the second end of the driven shaft in a direction toward the drive shaft exceeds a third predetermined displacement amount (D3) when the displacement amount of the second end of the driven shaft in a stopped state in which fluid is not compressed in the compression chamber is set to 0.

[0068] According to the claw compressor of the fifth aspect of the present disclosure, if the amount of displacement in the direction away from the drive shaft exceeds a third predetermined amount of displacement, it can be determined that an abnormal state exists due to damage to the driven bearing portion or other causes.

[0069] A claw compressor according to a sixth aspect of the present disclosure is the first or second aspect, further comprising the following configuration: a casing (11) to which the driven bearing is attached, and the measuring unit is fixed to the casing and measures the displacement amount based on the distance from a predetermined measuring position (61) to the driven shaft in the radial direction perpendicular to the first axis and the second axis.

[0070] According to the claw compressor of the sixth aspect of the present disclosure, the measuring unit is fixed to the casing unit to which the driven bearing unit is attached, and therefore, fixing the measuring unit to a location other than the casing unit can prevent problems such as vibrations in the compression chamber resulting in errors in the amount of displacement.

[0071] In a method for determining an abnormality of a claw compressor according to a seventh aspect of the present disclosure, the claw compressor includes a first rotor having a plurality of first claw portions protruding in a radial direction, a drive shaft connected to the first rotor and extending along a first axis, a drive bearing portion rotatably supporting the drive shaft, a drive portion connected to the drive shaft and generating a drive force for rotating the drive shaft, a second rotor having a plurality of second claw portions protruding in the radial direction, a driven shaft connected to the second rotor and extending along a second axis parallel to the first axis, a driven bearing portion rotatably supporting the driven shaft, and a drive force transmission section that transmits a drive force that rotates the drive shaft from the drive shaft to the driven shaft to rotate the driven shaft in the opposite direction to the drive shaft, and a compression section that forms a compression chamber that accommodates the first rotor and the second rotor, and the rotational axis of the driven shaft is measured. The rotational axis of the driven shaft is measured at a second end of the driven shaft opposite to a first end connected to the second rotor, and the rotational axis of the driven shaft is determined based on the displacement measured in the measurement section.

[0072] According to a method for detecting an abnormality in a claw compressor according to a seventh aspect of the present disclosure, in a compression chamber accommodating a first rotor and a second rotor, the first rotor connected to a drive shaft rotates about a first axis, the second rotor connected to a driven shaft rotates about a second axis in the opposite direction to the first rotor, and the first claws mesh with the second claws to compress the fluid. When the fluid is compressed, fluid pressure acts on a first end of the driven shaft connected to the second rotor in a radial direction perpendicular to the second axis and away from the first axis.

[0073] According to a seventh aspect of the present disclosure, a method for determining an abnormality of a claw compressor includes a measuring step for measuring a displacement of the driven shaft in a radial direction perpendicular to the first axis and the second axis at a second end of the driven shaft opposite a first end connected to the second rotor, and a determining step for determining an abnormal state of any of the first rotor, the second rotor, and the driven bearing based on the displacement. According to the seventh aspect of the present disclosure, a method for determining an abnormality of a claw compressor includes a measuring step for measuring an abnormal state of any of the first rotor connected to the drive shaft, the second rotor connected to the driven shaft, and the driven bearing that supports the driven shaft. [Explanation of symbols]

[0074] 1 Claw compressor 3 Compression section 5 Gear section 7 Front case 9 Main Case 9A recess 9a Inner wall 11 Gear case 12 Legs 13 Intake port 15 Outlet 20 compression chamber 21 Gear room 23 O-ring 24 Osrotor (1st rotor) 24a Claw part 24c recess 26 Female rotor (second rotor) 26a Claw part 26b Recess 26c recess 31 First Bolt 32 Drive shaft 37 Tip bearing (drive bearing part) 38 Rear end bearing (drive bearing part) 39 First timing gear (driving force transmission part) 41 Second bolt 42 Driven axis 42a First end 42b Second end 47 Tip bearing (driven bearing part) 48 Rear end bearing (driven bearing part) 49 Second timing gear (driving force transmission part) 50 Drive unit 60 Measurement section 61 Measurement location 62 Fixing member 70 Judgment section 80 Control Unit D Displacement D1 First predetermined displacement D2 Second predetermined displacement D3 Third specified displacement L distance O1 First rotation axis O2 Second rotation axis O3 measurement axis

Claims

1. a first rotor having a plurality of first claws protruding in a radial direction; a drive shaft connected to the first rotor and extending along a first axis; a drive bearing portion that rotatably supports the drive shaft; a drive unit connected to the drive shaft and generating a drive force to rotate the drive shaft; a second rotor having a plurality of second claws protruding in the radial direction; a driven shaft connected to the second rotor and extending along a second axis parallel to the first axis; a driven bearing portion that rotatably supports the driven shaft; a driving force transmission unit that transmits the driving force with which the driving unit rotates the drive shaft from the drive shaft to the driven shaft, thereby rotating the driven shaft in the direction opposite to that of the drive shaft; a compression section that defines a compression chamber that accommodates the first rotor and the second rotor; a measuring unit configured to measure a displacement of the driven shaft in the radial direction perpendicular to the first axis and the second axis at a second end of the driven shaft opposite to a first end connected to the second rotor; a determination unit that determines an abnormal state of any of the first rotor, the second rotor, and the driven bearing unit based on the amount of displacement measured by the measurement unit.

2. 2. The claw compressor according to claim 1, wherein the drive unit stops rotation of the drive shaft when the determination unit determines that any one of the first rotor, the second rotor, and the driven bearing unit is in an abnormal state.

3. 3. The claw compressor according to claim 1, wherein the determination unit determines that at least one of the first rotor and the second rotor is in an abnormal state when the displacement amount of the second end of the driven shaft in a direction away from the drive shaft exceeds a first predetermined displacement amount when the displacement amount of the second end of the driven shaft in a stopped state in which fluid is not compressed in the compression chamber is set to 0.

4. 4. The claw compressor according to claim 3, wherein the determination unit determines that the driven bearing unit is in an abnormal state if the displacement amount of the second end of the driven shaft in a direction away from the drive shaft exceeds a second predetermined displacement amount that is greater than the first predetermined displacement amount, when the displacement amount of the second end of the driven shaft in a stopped state in which fluid is not compressed in the compression chamber is set to 0.

5. 3. The claw compressor according to claim 1, wherein the determination unit determines that the driven bearing unit is in an abnormal state when the displacement amount of the second end of the driven shaft in a direction toward the drive shaft exceeds a third predetermined displacement amount, assuming that the displacement amount of the second end of the driven shaft in a stopped state in which fluid is not compressed in the compression chamber is zero.

6. a casing portion to which the driven bearing portion is attached, 3. The claw compressor according to claim 1, wherein the measurement unit is fixed to the casing unit and measures the displacement amount based on a distance from a predetermined measurement position in the radial direction perpendicular to the first axis and the second axis to the driven shaft.

7. A method for determining an abnormality in a claw compressor, comprising: The claw compressor is a first rotor having a plurality of first claws protruding in a radial direction; a drive shaft connected to the first rotor and extending along a first axis; a drive bearing portion that rotatably supports the drive shaft; a drive unit connected to the drive shaft and generating a drive force to rotate the drive shaft; a second rotor having a plurality of second claws protruding in the radial direction; a driven shaft connected to the second rotor and extending along a second axis parallel to the first axis; a driven bearing portion that rotatably supports the driven shaft; a driving force transmission unit that transmits the driving force with which the driving unit rotates the drive shaft from the drive shaft to the driven shaft, thereby rotating the driven shaft in the direction opposite to that of the drive shaft; a compression section that forms a compression chamber that accommodates the first rotor and the second rotor, a measuring step of measuring a displacement amount of the driven shaft in the radial direction perpendicular to the first axis and the second axis at a second end of the driven shaft opposite to a first end connected to the second rotor; and a determination step of determining an abnormal state of any of the first rotor, the second rotor, and the driven bearing portion based on the displacement amount measured in the measurement step.

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