Claw compressor

Abstract

Provided is a claw compressor comprising a male rotor (24), a female rotor, a compression part (3), and a seal part. The compression part (3) forms a compression chamber (20) between an accommodation surface (9b) and an accommodation surface (7a). The seal part increases the air-tightness of at least one of: a first clearance (CL1) between the accommodation surface (9b) and an end surface (24d), of the male rotor, facing the accommodation surface (9b); a second clearance between the accommodation surface (9b) and an end surface, of the female rotor, facing the accommodation surface (9b); a third clearance (CL3) between the accommodation surface (7a) and an end surface (24e), of the male rotor (24), facing the accommodation surface (7a); and a fourth clearance between the accommodation surface (7a) and an end surface, of the female rotor, facing the accommodation surface (7a).

Description

Claw compressor

[0001] The present disclosure relates to claw compressors.

[0002] A claw compressor includes a pair of rotors with hook-shaped claws inside a housing that defines a compression chamber. The rotors rotate at the same speed in opposite directions without contact while maintaining a predetermined clearance. The two rotors form a compression pocket, and the compressed fluid is discharged from the compression pocket. Such claw compressors are often used primarily as vacuum pumps and blowers (see, for example, Patent Document 1).

[0003] Patent No. 6845596

[0004] When a steam generation heat pump is used as an alternative to a boiler to compress the generated steam, the pressure difference between the suction pressure and the discharge pressure is larger than in a vacuum pump or blower, resulting in greater leakage, so it is necessary to reduce the gap during the compression process to improve efficiency.However, in the case of claw compressors used as vacuum pumps and blowers, the pressure difference between the suction pressure and the discharge pressure is small, so the issue of reducing the gap during the compression process does not arise, and no sufficient measures have been taken.

[0005] The present disclosure has been made in consideration of the above circumstances, and has an object to provide a claw compressor that can achieve high compression efficiency even when used for vapor compression.

[0006] A claw compressor according to one aspect of the present disclosure includes: a first rotor having a plurality of first claw portions projecting in a radial direction; a first rotating shaft that rotatably supports the first rotor; a second rotor that rotates in a direction opposite to the first rotor and has a plurality of second claw portions projecting in the radial direction; a second rotating shaft that rotatably supports the second rotor; a compression section that forms a compression chamber that accommodates the first rotor and the second rotor; and a seal section that enhances airtightness of a gap between the first rotor and the second rotor and the compression section, wherein the first rotor has a plurality of first recesses that receive the plurality of second claw portions, and the second rotor has , and a plurality of second recesses that receive a plurality of the first claw portions, the compression portion forms the compression chamber between a first accommodating surface and a second accommodating surface that are perpendicular to the first rotation axis and the second rotation axis, and the sealing portion enhances the airtightness of at least one of a first gap between the first accommodating surface and an end face of the first rotor facing the first accommodating surface, a second gap between the first accommodating surface and an end face of the second rotor facing the first accommodating surface, a third gap between the second accommodating surface and the end face of the first rotor facing the second accommodating surface, and a fourth gap between the second accommodating surface and the end face of the second rotor facing the second accommodating surface.

[0007] According to the present disclosure, it is possible to provide a claw compressor that can achieve high compression efficiency even in vapor compression applications.

[0008] 1. A perspective view showing a claw compressor according to a first embodiment of the present disclosure. 1. A cross-sectional view of the claw compressor taken along line II-II of FIG. 1. 2. A cross-sectional view taken along line III-III of FIG. 2. 3. A partially enlarged view showing the vicinity of the male rotor of the claw compressor shown in FIG. 2. 4. A partially enlarged view showing the vicinity of the female rotor of the claw compressor shown in FIG. 2. 5. A view of the male rotor and female rotor shown in FIG. 2 from the gear portion side. 6. A view of the male rotor and female rotor shown in FIG. 2 from the discharge port side. 7. A view of a first modified injection port of the first embodiment of the present disclosure. 8. A view of a second modified injection port of the first embodiment of the present disclosure. 9. A view of a third modified injection port of the first embodiment of the present disclosure. 10. A view of a fourth modified injection port of the first embodiment of the present disclosure. 11. A cross-sectional view showing the vicinity of the male rotor of a claw compressor according to a second embodiment of the present disclosure. 12. A cross-sectional view showing the vicinity of the female rotor of a claw compressor according to a second embodiment of the present disclosure. 13. A view of the male rotor and female rotor shown in FIGS. 12 and 13 from the gear portion side. 14. A view of the male rotor and female rotor shown in FIGS. 12 and 13 from the discharge port side. 10A and 10B are cross-sectional views showing the vicinity of a male rotor and a female rotor of a claw compressor according to a modified example of the second embodiment of the present disclosure, respectively.

[0009] Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings. First Embodiment Hereinafter, a first embodiment of the present disclosure will be described. As shown in FIG. 1 , a claw compressor 1 includes a compression section 3 having a compression chamber formed therein, and a gear section 5 accommodating a timing gear. The compression section 3 is formed by a first housing 7 and a second housing 9, and the gear section 5 is formed by the second housing 9 and a third housing 11. The claw compressor 1 is installed upright on an installation surface by means of, for example, four legs 12.

[0010] 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 pressure or positive pressure.

[0011] 2, the compression unit 3 is configured such that a compression chamber 20 is formed inside by covering a recess formed in the front end (one side end) of the second housing 9 with the first housing 7. The first housing 7 is airtightly attached to the second housing 9 via an O-ring 22.

[0012] The first housing 7 has a housing surface (second housing surface) 7a that is perpendicular to the first rotation shaft 32 and the second rotation shaft 42 and is disposed on the discharge port 15 side. The second housing 9 has a housing surface (first housing surface) 9b that is perpendicular to the first rotation shaft 32 and the second rotation shaft 42 and is disposed on the gear unit 5 side. The compression unit 3 forms a compression chamber 20 between the housing surface 9b and the housing surface 7a.

[0013] The compression chamber 20 is provided with a pair of rotors, namely a male rotor (first rotor) 24 and a female rotor (second rotor) 26 .

[0014] As shown in Fig. 3, the male rotor 24 has a pair of hook-shaped claws (first claws) 24a. The claws 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 the direction of arrow A1) in Fig. 3.

[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.

[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 recesses (first recesses) 24b that receive the claws 26a of the female rotor 26 during the compression stroke. The female rotor 26 is formed with recesses (second recesses) 26b that receive the claws 24a of the male rotor 24 during the compression stroke. The compressed steam is discharged from the discharge port 15, which is generally triangular in shape in Figure 3.

[0017] 3, the shape of compression chamber 20 is defined by inner wall 9a of second housing 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 second housing 9 with a predetermined clearance.

[0018] As shown in Fig. 2, the male rotor 24 is fastened to the first rotating shaft 32 by a first bolt 31. Specifically, as shown in Fig. 2, the first bolt 31 is screwed onto the first rotating shaft 32 with the axis of the first bolt 31 coinciding with the first rotation axis O1. A fastening structure (first bolt fastening portion) is configured with the center of the male rotor 24 sandwiched between the tip surface of the first rotating 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] A key 35 (anti-rotation portion) is provided between the male rotor 24 and the tip end of the first rotating shaft 32. The key 35 is fitted into key grooves formed in the male rotor 24 and the first rotating shaft 32, and prevents relative rotation between the male rotor 24 and the first rotating shaft 32.

[0020] The female rotor 26 is fastened to the second rotation shaft 42 by a second bolt 41. Specifically, the second bolt 41 is screwed onto the second rotation shaft 42 with the axis of the second bolt 41 coinciding with the second rotation axis O2. The second rotation shaft 42 is provided parallel to the first rotation shaft 32. In other words, the first rotation axis O1 and the second rotation axis O2 are parallel to each other.

[0021] A fastening structure (second bolt fastening portion) is configured with the center of the female rotor 26 sandwiched between the tip surface of the second rotating 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. The key 35 provided between the male rotor 24 and the first rotating shaft 32 is not provided between the female rotor 26 and the second rotating shaft 42. Therefore, before the female rotor 26 is fixed by the second bolt 41, relative rotation between the female rotor 26 and the second rotating shaft 42 is permitted.

[0022] The first rotating 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 (not shown). The drive unit may be, for example, an electric motor. The first rotating shaft 32 rotates about a first rotation axis O1, thereby rotating the male rotor 24 within the compression chamber 20. The first rotating shaft 32 is rotatably supported at two locations: a tip-side bearing 37 and a rear-side bearing 38.

[0023] The front end bearing 37 is provided in the second housing 9 and is, for example, a double-row ball bearing. However, the front end bearing 37 is not limited to a double-row ball bearing. The rear end bearing 38 is located further rearward than the front end bearing 37 and is provided in the third housing 11. The rear end bearing 38 is, for example, a single-row ball bearing, but is not limited to a single-row ball bearing.

[0024] A first timing gear 39 is fixed to the first rotating shaft 32 between the front-end bearing 47 and the rear-end bearing 38. The first timing gear 39 is, for example, a spur gear, and rotates together with the first rotating shaft 32 around the first rotation axis O1.

[0025] 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 (other side end) of the second housing 9 and the front end of the third housing 11. The second housing 9 and the third housing 11 are attached liquid-tightly via an O-ring 23 so as to seal in the lubricating oil in the gear chamber 21.

[0026] The second rotary shaft 42 supporting the female rotor 26 has a leading end located within the compression chamber 20 and a trailing end terminated in the third housing 11 .

[0027] The second rotary shaft 42 rotates about the second rotation axis O2, causing the female rotor 26 to rotate within the compression chamber 20. The second rotary shaft 42 is rotatably supported at two locations: a front-end bearing 47 and a rear-end bearing 48. The front-end bearing 47 is provided in the second housing 9 and is, for example, a double-row ball bearing. However, the front-end bearing 47 is not limited to a double-row ball bearing. The rear-end bearing 48 is located rearward of the front-end bearing 47 and is provided in the third housing 11. The rear-end bearing 48 is a single-row ball bearing, but is not limited to a single-row ball bearing.

[0028] A second timing gear 49 is fixed to the second rotating shaft 42 between the front-end bearing 47 and the rear-end bearing 48. The second timing gear 49 is, for example, a spur gear, and rotates together with the second rotating shaft 42 about the second rotation axis O2.

[0029] The second timing gear 49 is provided in the gear unit 5 and housed in the gear chamber 21. The second timing gear 49 is in mesh with the first timing gear 39, and receives driving force from the first timing gear 39. Therefore, the first rotating shaft 32 serves as a driving shaft, and the second rotating shaft 42 serves as a driven shaft.

[0030] The claw compressor 1 configured as described above operates as follows: The first rotary shaft 32 is rotationally driven by a drive unit (not shown), causing the male rotor 24 to rotate within the compression chamber 20. The second rotary shaft 42 is rotated by the second timing gear 49, to which a rotational driving force is transmitted from the first timing gear 39, which rotates together with the first rotary shaft 32, causing the female rotor 26 to rotate within the compression chamber 20.

[0031] 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 Figure 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 Figure 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.

[0032] 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.

[0033] When assembling the claw compressor, the phase adjustment of the rotors 24, 26 is performed as follows: First, with the tip end side (compression chamber 20 side) of the second housing 9 open, a key 35 is attached between the male rotor 24 and the first rotating shaft 32. This prevents rotation with the key 35, uniquely determining the relative position of the male rotor 24 with respect to the first rotating shaft 32 in the rotational direction. Then, the male rotor 24 is fastened to the first rotating shaft 32 with the first bolts 31.

[0034] Next, the female rotor 26 is fastened to the second rotating shaft 42 using the second bolts 41. At this time, the position in the rotational direction relative to the second rotating shaft 42 is adjusted to a desired value before fastening using the second bolts 41. Then, the first housing 7 is attached to the tip side of the second housing 9 to form the compression chamber 20.

[0035] Next, the seal portion 50 that improves the airtightness of the gaps between the male rotor 24 and the female rotor 26 and the compression section 3 to improve compression efficiency will be described with reference to the drawings. Fig. 4 is a partial enlarged view showing the vicinity of the male rotor 24 of the claw compressor 1 shown in Fig. 2. Fig. 5 is a partial enlarged view showing the vicinity of the female rotor 26 of the claw compressor 1 shown in Fig. 2. Fig. 6 is a view of the male rotor 24 and the female rotor 26 shown in Fig. 2 as seen from the gear section 5 side. Fig. 7 is a view of the male rotor 24 and the female rotor 26 shown in Fig. 2 as seen from the discharge port 15 side.

[0036] The seal portion 50 of this embodiment includes a tip seal 51, a tip seal 52, and a tip seal 53. The tip seals 51, 52, and 53 are members formed of a highly wear-resistant resin material (e.g., polyphenylene sulfide (PPS) or polytetrafluoroethylene (PTFE)). As shown in FIGS. 4 and 6 , the tip seal 51 is a member that airtightly seals a first gap CL1 between the housing surface 9b of the compression portion 3 and the end face 24d of the male rotor 24 that faces the housing surface 9b. The tip seal 51 is disposed in a first groove portion 24d1 formed in the end face 24d.

[0037] 5 and 6 , the tip seal 52 is a member that airtightly seals a second gap CL2 between the housing surface 9b of the compression section 3 and the end face 26d of the female rotor 26 that faces the housing surface 9b. The tip seal 52 is disposed in a second groove portion 26d1 formed in the end face 26d.

[0038] 4 and 7, the tip seal 53 is a member that airtightly seals a third gap CL3 between the housing surface 7a of the compression section 3 and the end face 24e of the male rotor 24 that faces the housing surface 7a. The tip seal 53 is disposed in a third groove portion 24e1 formed in the end face 24e.

[0039] 5 and 7, no tip seal is disposed in the fourth gap CL4 between the housing surface 7a of the compression section 3 and the end face 26e of the female rotor 26 facing the housing surface 7a. The reason why no tip seal is disposed in the fourth gap CL4 is that the discharge port 15 for discharging compressed steam between the claws 24a of the male rotor 24 and the recesses 26b of the female rotor 26 or between the claws 26a of the female rotor 26 and the recesses 24b of the male rotor 24 is formed in the region of the housing surface 7a of the compression section 3 facing the end face 26e of the female rotor 26. If a tip seal were disposed in the fourth gap CL4, the tip seal would come into contact with the corner of the boundary between the discharge port 15 and the housing surface 7a and be worn out.

[0040] In this embodiment, tip seals are disposed in the first clearance CL1, the second clearance CL2, and the third clearance CL3, and no tip seal is disposed in the fourth clearance CL4, but other configurations are also possible. For example, a tip seal may be disposed in at least one of the first clearance CL1, the second clearance CL2, the third clearance CL3, and the fourth clearance CL4. If a tip seal is disposed in the fourth clearance CL4, a groove for accommodating the tip seal is provided in the end face 26e of the female rotor 26.

[0041] As shown in FIGS. 3 and 5 , the claw compressor 1 of this embodiment is provided with an injection port (fluid supply port) 60 that supplies a fluid (e.g., water) to the compression chamber 20 to lower the temperature of steam compressed between the claw portions 24 a of the male rotor 24 and the recesses 26 b of the female rotor 26 or between the claw portions 26 a of the female rotor 26 and the recesses 24 b of the male rotor 24.

[0042] The injection port 60 of this embodiment discharges fluid into a fourth gap CL4 between the housing surface 7a of the compression section 3 and the end face 26e of the female rotor 26 facing the housing surface 7a. The injection port 60 is located on the housing surface 7a facing the fourth gap CL4 because no tip seal is located on the end face 26e of the female rotor 26 facing the fourth gap CL4. Because no tip seal is located on the end face 26e of the female rotor 26, the tip seal is not worn down due to contact with the injection port 60.

[0043] The injection port 60 of this embodiment may be arranged to discharge fluid into the third gap CL3, for example, when a tip seal 53 is not arranged on the end face 24e of the male rotor 24 facing the third gap CL3. In this case, the claw compressor 1 includes a tip seal 51 arranged in the first groove portion 24d1 and a tip seal 52 arranged in the second groove portion 26d1. The injection port 60 supplies fluid from the accommodation surface 7a to the third gap CL3 and the fourth gap CL4.

[0044] The claw compressor 1 of this embodiment includes a temperature sensor (not shown) that detects the temperature of steam discharged from the discharge port 15, a flow control valve (not shown) that is disposed in a pipe that communicates with the injection port 60, and a control unit (not shown) that controls the aperture of the flow control valve. The control unit controls the aperture of the flow control valve so that the temperature detected by the temperature sensor is maintained within a predetermined temperature range (for example, a range of 140°C or higher and 160°C or lower).

[0045] The claw compressor 1 of this embodiment described above provides the following actions and effects. The seal portion 50 improves the airtightness of at least one of the first gap CL1 between the housing surface 9 b and the end face 24 d of the male rotor 24 facing the housing surface 9 b, the second gap CL2 between the housing surface 9 b and the end face 26 d of the female rotor 26 facing the housing surface 9 b, the third gap CL3 between the housing surface 7 a and the end face 24 e of the male rotor 24 facing the housing surface 7 a, and the fourth gap CL4 between the housing surface 7 a and the end face 26 e of the female rotor 26 facing the housing surface 7 a. Therefore, high compression efficiency can be achieved when the claw compressor 1 is used for steam compression.

[0046] Furthermore, according to the claw compressor 1 of this embodiment, by disposing the tip seal 51 in the first groove portion 24d1, the tip seal 52 in the second groove portion 26d1, and the tip seal 53 in the third groove portion 24e1, it is possible to improve the airtightness of the first gap CL1, the second gap CL2, and the third gap CL3. Furthermore, since no tip seal is disposed in the fourth gap CL4, disposing a tip seal in the fourth gap CL4 can prevent the tip seal from coming into contact with the corners of the boundary between the discharge port 15 and the accommodation surface 7a and becoming worn.

[0047] [First Modification] In the present embodiment, the injection port 60 discharges fluid into the fourth gap CL4 between the housing surface 7a of the compression section 3 and the end surface 26e of the female rotor 26 facing the housing surface 7a, but other configurations are also possible. For example, an injection port 60A of a first modification shown in Fig. 8 may be used. Fig. 8 is a diagram showing a first modification of the injection port 60 of the first embodiment of the present disclosure.

[0048] The injection port 60A of the first modified example shown in FIG. 8 is a port that supplies fluid (e.g., water) from a fluid supply source (not shown) to the compression chamber 20 via the internal flow path 42A of the second rotating shaft 42 and the internal flow path 26f of the female rotor 26. The internal flow path 26f supplies the fluid toward the bottom surface of the second groove 26d1 in which the tip seal 52 is housed. The tip seal 52 is pressed toward the housing surface 9b by the pressure of the fluid flowing from the internal flow path 26f into the second groove 26d1. Because a biasing force toward the housing surface 9b acts on the tip seal 52, the airtightness between the tip seal 52 and the housing surface 9b is improved.

[0049] Although the injection port 60A of the first modified example shown in FIG. 8 supplies fluid toward the bottom surface of the second groove 26d1 in which the tip seal 52 is housed, other configurations are also possible. For example, the injection port 60A may supply fluid toward the bottom surface of the first groove 24d1 in which the tip seal 51 is housed. Alternatively, the injection port 60A may supply fluid toward the bottom surface of the third groove 24e1 in which the tip seal 53 is housed. The injection port 60A may supply fluid to at least one of the first groove 24d1, the second groove 26d1, and the third groove 24e1.

[0050] [Second Modification] In the present embodiment, the injection port 60 discharges fluid into the fourth gap CL4 between the housing surface 7a of the compression section 3 and the end surface 26e of the female rotor 26 facing the housing surface 7a, but other configurations are also possible. For example, an injection port 60B of a second modification shown in Fig. 9 may be used. Fig. 9 is a diagram showing a second modification of the injection port 60 of the first embodiment of the present disclosure.

[0051] The injection port 60B shown in Figure 9 is a port that communicates with a recess 7b formed in the first housing 7 to connect the first space S1 and the second space S2 within the compression chamber 20 when the suction process is performed to draw steam into the compression chamber 20 from the suction port 13 after the compression process to discharge compressed steam from the discharge port 15 is completed.

[0052] The first space S1 is a space that generates negative pressure, and if this space were left sealed, excessive power would be required to rotate the male rotor 24 and the female rotor 26. Therefore, a recess 7b is formed in the first housing 7 to communicate the first space S1 with the second space S2. If the injection port 60B were connected to the space where compressed steam is sealed during the compression process of the compression chamber 20, the compressed steam would backflow into the injection port 60B. Therefore, in the second modified example, the injection port 60B is provided to communicate with the recess 7b, thereby making it possible to appropriately prevent the compressed steam from backflowing.

[0053] [Third Modification] In the present embodiment, the injection port 60 discharges fluid into the fourth gap CL4 between the housing surface 7a of the compression section 3 and the end surface 26e of the female rotor 26 facing the housing surface 7a, but other configurations are also possible. For example, an injection port 60C of a third modification shown in Fig. 10 may be used. Fig. 10 is a diagram illustrating a third modification of the injection port 60 of the first embodiment of the present disclosure.

[0054] The claw compressor 1 of the third modified example includes an injection port 60C that supplies a fluid to the compression chamber 20 to lower the temperature of the steam compressed by the male rotor 24 and the female rotor 26. The second housing 9 of the compression section 3 has a connecting surface 9c that connects the accommodation surface 7a and the accommodation surface 9b and is disposed so as to radially surround the compression chamber 20. The injection port 60C supplies the fluid (e.g., water) from the outside of the connecting surface 9c toward a gap CL5 between the female rotor 26 of the compression chamber 20 and the connecting surface 9c along a radial direction perpendicular to the first rotation shaft 32 and the second rotation shaft 42.

[0055] [Fourth Modification] The claw compressor 1 of the third modification is provided with the injection port 60C that supplies fluid from the outside of the coupling surface 9c toward the compression chamber 20, but other configurations may be used. For example, an injection port 60D of a fourth modification shown in Fig. 11 may be used. Fig. 11 is a diagram showing a fourth modification of the injection port 60 of the first embodiment of the present disclosure. The injection port 60D of the fourth modification shown in Fig. 11 is a port that supplies fluid (e.g., water) from a fluid supply source (not shown) to the compression chamber 20 via the internal flow path 42D of the second rotating shaft 42 and the internal flow path 26g of the female rotor 26.

[0056] The injection port 60D of the fourth modified example branches the fluid guided from the internal flow path 42D of the second rotating shaft 42 in three directions in the internal flow path 26g and guides it in a radial direction perpendicular to the second rotating shaft 42, supplying the fluid (e.g., water) from the tip of the claw portion 26a toward the gap CL5 between the female rotor 26 and the connecting surface 9c.

[0057] Second Embodiment Next, a claw compressor 1 according to a second embodiment of the present disclosure will be described with reference to the drawings. The claw compressor 1 according to the first embodiment enhances the airtightness of the gaps between the male rotor 24 and the female rotor 26 and the inner circumferential surfaces of the compression chambers 20 by disposing chip seals in at least one of the first gap CL1, the second gap CL2, the third gap CL3, and the fourth gap CL4. In contrast, the claw compressor 1 according to this embodiment enhances the airtightness of the gaps between the male rotor 24 and the female rotor 26 and the inner circumferential surfaces of the compression chambers 20 by supplying fluid to at least one of the first gap CL1, the second gap CL2, the third gap CL3, and the fourth gap CL4.

[0058] Fig. 12 is a cross-sectional view showing the vicinity of the male rotor 24 of the claw compressor 1 according to the second embodiment of the present disclosure. Fig. 13 is a cross-sectional view showing the vicinity of the female rotor 26 of the claw compressor 1 according to the second embodiment of the present disclosure. Fig. 14 is a view of the male rotor 24 and female rotor 26 shown in Figs. 12 and 13 as viewed from the gear portion 5 side. Fig. 15 is a view of the male rotor 24 and female rotor 26 shown in Figs. 12 and 13 as viewed from the discharge port 15 side.

[0059] As shown in Fig. 12, a first groove 24d1 is formed in the end face 24d of the male rotor 24 facing the housing surface 9b, and a third groove 24e1 is formed in the end face 24e of the male rotor 24 facing the housing surface 7a. As shown in Fig. 13, a second groove 26d1 is formed in the end face 26d of the female rotor 26 facing the housing surface 9b, and a fourth groove 26e1 is formed in the end face 26e of the female rotor 26 facing the housing surface 7a.

[0060] 12 , the claw compressor 1 of this embodiment has an injection port 60E that supplies fluid (e.g., water) from a fluid supply source (not shown) to the compression chamber 20 via the internal flow passage 32E of the first rotating shaft 32 and the internal flow passage 24f of the male rotor 24. The injection port 60E is a port that supplies the fluid (e.g., water) to the compression chamber 20 to lower the temperature of the steam compressed by the male rotor 24 and the female rotor 26. The internal flow passage 24f supplies the fluid toward the bottom surfaces of the first groove portion 24d1 and the third groove portion 24e1.

[0061] The fluid supplied to the bottom surface of the first groove 24d1 is supplied to the region of the first gap CL1 between the housing surface 9b and the end face 24d of the male rotor 24 that faces the first groove 24d1, forming a first seal region Se1 that corresponds to the shape of the first groove 24d1. This improves the airtightness between the first groove 24d1 and the housing surface 9b. As shown in Figure 14, the first seal region Se1 has a shape that corresponds to the shape of the first groove 24d1.

[0062] The fluid supplied to the bottom surface of the third groove 24e1 is supplied to the area of ​​the third gap CL3 between the housing surface 7a and the end face 24e of the male rotor 24, which faces the third groove 24e1, and forms a third seal area Se3 that corresponds to the shape of the third groove 24e1. This improves the airtightness between the third groove 24e1 and the housing surface 7a. As shown in Figure 15, the third seal area Se3 has a shape that corresponds to the third groove 24e1.

[0063] 13 , the claw compressor 1 of this embodiment has an injection port 60F that supplies fluid (e.g., water) from a fluid supply source (not shown) to the compression chamber 20 via the internal flow path 42F of the second rotating shaft 42 and the internal flow path 26g of the female rotor 26. The injection port 60F is a port that supplies the fluid (e.g., water) to the compression chamber 20 to lower the temperature of the steam compressed by the male rotor 24 and the female rotor 26. The internal flow path 26g supplies the fluid toward the bottom surfaces of the second groove portion 26d1 and the fourth groove portion 26e1.

[0064] The fluid supplied to the bottom surface of the second groove 26d1 is supplied to the region of the second gap CL2 between the housing surface 9b and the end face 26d of the female rotor 26 that faces the second groove 26d1, thereby forming a second seal region Se2 that corresponds to the shape of the second groove 26d1. This improves the airtightness between the second groove 26d1 and the housing surface 9b. As shown in FIG. 14 , the second seal region Se2 has a shape that corresponds to the shape of the second groove 26d1.

[0065] The fluid supplied to the bottom surface of the fourth groove 26e1 is supplied to the region of the fourth gap CL4 between the housing surface 7a and the end face 26e of the female rotor 26 that faces the fourth groove 26e1, forming a fourth seal region Se4 that corresponds to the shape of the fourth groove 26e1. This improves the airtightness between the fourth groove 26e1 and the housing surface 7a. As shown in FIG. 15 , the fourth seal region Se4 has a shape that corresponds to the fourth groove 26e1.

[0066] According to the claw compressor 1 of the present embodiment, by supplying a fluid for lowering the temperature of the steam to the first groove portion 24d1, the second groove portion 26d1, the third groove portion 24e1, and the fourth groove portion 26e1, it is possible to maintain at an appropriate temperature the temperature of the steam discharged from the discharge port 15. Furthermore, by forming seal areas corresponding to the shapes of the first groove portion 24d1, the second groove portion 26d1, the third groove portion 24e1, and the fourth groove portion 26e1 using the fluid, it is possible to improve the airtightness of the first gap CL1, the second gap CL2, the third gap CL3, and the fourth gap CL4.

[0067] [Modifications] The claw compressor 1 of the present embodiment includes the injection port 60E that supplies fluid from the internal flow path 32E of the first rotating shaft 32 to the internal flow path 24f of the male rotor 24, and the injection port 60F that supplies fluid from the internal flow path 42F of the second rotating shaft 42 to the internal flow path 26g of the female rotor 26, but other configurations are also possible. For example, the claw compressor 1 may include an injection port 60G that supplies fluid from the first housing 7 to the internal flow path 24g of the male rotor 24, and an injection port 60H that supplies fluid from the first housing 7 to the internal flow path 26h of the female rotor 26.

[0068] Fig. 16 is a cross-sectional view showing the vicinity of the male rotor 24 of the claw compressor 1 according to a modified example of the second embodiment of the present disclosure. Fig. 17 is a cross-sectional view showing the vicinity of the female rotor 26 of the claw compressor 1 according to a modified example of the second embodiment of the present disclosure.

[0069] 16 , the claw compressor 1 according to the modified example includes an injection port 60G that supplies fluid from the first housing 7 to the recess 24c of the male rotor 24. The fluid supplied from the injection port 60G to the recess 24c is guided to the third groove 24e1 via grooves 24e2 and 24e3 formed in the end face 24e of the male rotor 24. The fluid guided to the third groove 24e1 is then guided to the first groove 24d1 via the internal flow path 24g.

[0070] 17 , the claw compressor 1 according to the modified example includes an injection port 60H that supplies fluid from the first housing 7 to the recess 26c of the female rotor 26. The fluid supplied from the injection port 60H to the recess 26c is guided to the fourth groove 26e1 via grooves 26e2 and 26e3 formed in the end face 26e of the female rotor 26. The fluid guided to the fourth groove 26e1 is then guided to the second groove 26d1 via the internal flow path 26h.

[0071] While the male rotor 24 has a pair of claws 24 a and a pair of recesses 24 b, and the female rotor 26 has a pair of claws 26 a and a pair of recesses 26 b in the above description, other embodiments are also possible. For example, the male rotor 24 may have three or more claws 24 a and three or more recesses 24 b, and the female rotor 26 may have three or more claws 26 a and three or more recesses 26 b.

[0072] By doing so, the compression stroke occurs regardless of the timing when the male rotor 24 rotates once around the first rotation shaft 32 and the female rotor 26 rotates once around the second rotation shaft 42. Therefore, it is possible to prevent errors due to backlash caused by disengagement of the gear portion 5 due to timing when the compression stroke does not occur.

[0073] The claw compressor according to each of the above-described embodiments can be understood as follows, for example: A claw compressor according to a first aspect of the present disclosure includes a first rotor (24) having a plurality of first claw portions (24a) projecting in the radial direction, a first rotating shaft (32) that rotatably supports the first rotor, a second rotor (26) that rotates in the opposite direction to the first rotor and has a plurality of second claw portions (26a) projecting in the radial direction, a second rotating shaft (42) that rotatably supports the second rotor, a compression section (3) that forms a compression chamber (20) that houses the first rotor and the second rotor, and a seal section (50) that enhances airtightness of a gap between the first rotor and the second rotor and the compression section, wherein the first rotor has a plurality of first recesses (24b) that receive the plurality of second claw portions, and the second rotor has a plurality of second recesses (24b) that receive the plurality of second claw portions. The compression section has a plurality of second recesses (26b) that receive first claw portions, and the compression section forms the compression chamber between a first accommodating surface (9b) and a second accommodating surface (7a) that are perpendicular to the first rotation axis and the second rotation axis, and the sealing section enhances the airtightness of at least one of a first gap (CL1) between the first accommodating surface and an end face (24d) of the first rotor facing the first accommodating surface, a second gap (CL2) between the first accommodating surface and an end face (26d) of the second rotor facing the first accommodating surface, a third gap (CL3) between the second accommodating surface and an end face (24e) of the first rotor facing the second accommodating surface, and a fourth gap (CL4) between the second accommodating surface and an end face (26e) of the second rotor facing the second accommodating surface.

[0074] In the claw compressor according to the first aspect of the present disclosure, the seal portion increases the airtightness of at least one of a first gap between the first housing surface and the end face of the first rotor facing the first housing surface, a second gap between the first housing surface and the end face of the second rotor facing the first housing surface, a third gap between the second housing surface and the end face of the first rotor facing the second housing surface, and a fourth gap between the second housing surface and the end face of the second rotor facing the second housing surface, thereby achieving high compression efficiency when the claw compressor is used for vapor compression.

[0075] The claw compressor according to a second aspect of the present disclosure is the first aspect, further including the following configuration: That is, the seal portion has a first tip seal (51) arranged in a first groove (24d1) formed in an end face of the first rotor facing the first accommodating surface, a second tip seal (52) arranged in a second groove (26d1) formed in an end face of the second rotor facing the first accommodating surface, and a third tip seal (53) arranged in a third groove (24e1) formed in the end face of the first rotor facing the second accommodating surface, and a discharge port (15) for discharging steam compressed between the first claw portion and the first recess or between the second claw portion and the second recess is formed in a region of the second accommodating surface facing the end face of the second rotor.

[0076] According to the claw compressor of the second aspect of the present disclosure, the first tip seal is disposed in the first groove, the second tip seal is disposed in the second groove, and the third tip seal is disposed in the third groove, thereby improving the airtightness of the first gap, the second gap, and the third gap. Furthermore, since no tip seal is disposed in the fourth gap, disposing a tip seal in the fourth gap can prevent the tip seal from coming into contact with the corner of the boundary between the discharge port and the second storage surface and becoming worn.

[0077] The claw compressor according to a third aspect of the present disclosure is the same as the second aspect, but further includes the following configuration. Specifically, it has a fluid supply port (60A) that supplies a fluid for lowering the temperature of the steam to at least one of the first groove, the second groove, and the third groove. According to the claw compressor according to the third aspect of the present disclosure, the fluid for lowering the temperature of the steam is supplied to at least one of the first groove, the second groove, and the third groove, so that the temperature of the steam discharged from the discharge port can be maintained at an appropriate temperature. Furthermore, a biasing force of the fluid acts on at least one of the first tip seal, the second tip seal, and the third tip seal, improving the sealing performance of the tip seals.

[0078] The claw compressor according to a fourth aspect of the present disclosure is the same as the second aspect, but further includes the following configuration: a fluid supply port (60) that supplies a fluid to the compression chamber for lowering the temperature of the steam compressed between the first claw portion and the first recess or between the second claw portion and the second recess, and the fluid supply port supplies the fluid from the second accommodating surface to the fourth gap. According to the claw compressor according to the fourth aspect of the present disclosure, because the fluid is supplied from the second accommodating surface to the fourth gap where no tip seal is disposed, the problem of tip seal wear due to the fluid supply port provided in the second accommodating surface does not occur.

[0079] A claw compressor according to a fifth aspect of the present disclosure is the first aspect, further comprising the following configuration: a fluid supply port (60) that supplies, to the compression chamber, a fluid for lowering the temperature of steam compressed between the first claw portion and the first recess or between the second claw portion and the second recess, the seal portion having a first tip seal (51) disposed in a first groove portion (24d1) formed in an end face of the first rotor facing the first accommodating surface and a second tip seal (52) disposed in a second groove portion (26d1) formed in an end face of the second rotor facing the first accommodating surface, and the fluid supply port supplies fluid from the second accommodating surface to the third gap and the fourth gap.

[0080] According to the claw compressor of the fifth aspect of the present disclosure, fluid is supplied from the second storage surface to the third gap and the fourth gap where no tip seal is arranged, so that there is no problem of the tip seal being worn down by the fluid supply port provided on the second storage surface.

[0081] A claw compressor according to a sixth aspect of the present disclosure is the first aspect, further comprising the following configuration: a fluid supply port (60C) that supplies a fluid to the compression chamber for reducing the temperature of steam compressed between the first claw portion and the first recess or between the second claw portion and the second recess, the compression portion having a connecting surface (9c) that connects the first accommodating surface and the second accommodating surface and is disposed so as to surround the compression chamber, and the fluid supply port supplies the fluid from the connecting surface to the compression chamber along a radial direction perpendicular to the first rotation axis and the second rotation axis.

[0082] According to the claw compressor of the sixth aspect of the present disclosure, by supplying fluid from the connecting surface to the compression chamber along a radial direction perpendicular to the first rotating shaft and the second rotating shaft, the fluid can be supplied to the compression chamber without wearing out the tip seal, and the temperature of the steam discharged from the discharge port can be maintained at an appropriate temperature.

[0083] A claw compressor according to a seventh aspect of the present disclosure is the same as that of the first aspect, further comprising the following configuration: a fluid supply port (60A) that supplies a fluid for lowering the temperature of steam compressed between the first claw portion and the first recess or between the second claw portion and the second recess to the compression chamber via an internal flow path (26f) formed inside the second rotor. According to the claw compressor according to the seventh aspect of the present disclosure, the fluid supply port supplies a fluid to the compression chamber via the internal flow path (26f) formed inside the second rotor, thereby making it possible to maintain the temperature of steam discharged from a discharge port at an appropriate temperature.

[0084] A claw compressor according to an eighth aspect of the present disclosure is the same as the seventh aspect, further including the following configuration. That is, the compression chamber has a connecting surface (9c) that connects the first and second storage surfaces and is arranged to surround the compression chamber, and the fluid supply port (60C) supplies fluid to a gap between the second rotor and the connecting surface. According to the claw compressor according to the eighth aspect of the present disclosure, by supplying fluid to the gap between the second rotor and the connecting surface via an internal flow path (26f) formed inside the second rotor, it is possible to supply fluid to the compression chamber without wearing down the tip seal and maintain the temperature of steam discharged from the discharge port at an appropriate temperature.

[0085] A claw compressor according to a ninth aspect of the present disclosure is the first aspect, further including the following configuration: a first groove (24d1) is formed in an end face of the first rotor facing the first housing surface, a second groove (26d1) is formed in an end face of the second rotor facing the first housing surface, a third groove (24e1) is formed in an end face of the first rotor facing the second housing surface, and a fourth groove (26e1) is formed in an end face of the second rotor facing the second housing surface, and the seal portion has fluid supply ports (60E, 60F) that supply a fluid for lowering the temperature of the steam to the first groove, the second groove, the third groove, and the fourth groove.

[0086] According to the claw compressor of the ninth aspect of the present disclosure, the temperature of steam discharged from the discharge port can be maintained at an appropriate temperature by supplying a fluid for lowering the temperature of steam to the first groove, the second groove, the third groove, and the fourth groove. Also, sealing regions corresponding to the shapes of the first groove, the second groove, the third groove, and the fourth groove can be formed with the fluid, thereby improving the airtightness of the first gap, the second gap, the third gap, and the fourth gap.

[0087] A claw compressor according to a tenth aspect of the present disclosure is the claw compressor of any of the third to ninth aspects, further comprising the following configuration: an adjustment valve that adjusts the amount of fluid supplied from the fluid supply port to the compression chamber in accordance with the temperature of the fluid discharged from the compression chamber. According to the claw compressor according to the tenth aspect of the present disclosure, the temperature of the fluid discharged from the compression chamber can be maintained within an appropriate range by adjusting the amount of fluid supplied from the fluid supply port to the compression chamber in accordance with the temperature of the fluid discharged from the compression chamber.

[0088] REFERENCE SIGNS LIST 1 Claw compressor 3 Compression section 5 Gear section 7 First housing 7a Accommodation surface 7b Recess 9 Second housing 9a Inner wall 9b Accommodation surface 9c Connection surface 11 Third housing 13 Intake port 15 Discharge port 20 Compression chamber 21 Gear chamber 24 Male rotor (first rotor) 24a, 26a Claw portion 24b, 26b Recess 24c, 26c Recess 24d, 24e, 26d, 26e End surface 24d1 First groove portion 24e2, 24e3, 26e2, 26e3 Groove portion 24e1 Third groove portion 24f, 24g, 26f, 26g, 26h, 32E, 42A, 42D, 42F Internal flow path 26 Female rotor (second rotor) 26d1 Second groove portion 26e1 Fourth groove portion 32 First rotating shaft 42 Second rotating shaft 50 Seal portion 51, 52, 53 Tip seal 60, 60A, 60B, 60C, 60D, 60E, 60F, 60G, 60H Fluid supply port CL1 First gap CL2 Second gap CL3 Third gap CL4 Fourth gap O1 First rotation axis O2 Second rotation axis S1 First space S2 Second space Se1 First seal area Se2 Second seal area Se3 Third seal area Se4 Fourth seal area

Claims

1. A compressor comprising: a first rotor having a plurality of first claw portions protruding in the radial direction; a first rotating shaft which rotatably supports the first rotor; a second rotor which rotates in the opposite direction to the first rotor and has a plurality of second claw portions protruding in the radial direction; a second rotating shaft which rotatably supports the second rotor; a compression section which forms a compression chamber which accommodates the first rotor and the second rotor; and a sealing section which enhances airtightness of a gap between the first rotor and the second rotor and the compression section, wherein the first rotor has a plurality of first recesses which receive the plurality of second claw portions; the second rotor has a plurality of second recesses which receive the plurality of first claw portions; and the compression section forms the compression chamber between a first accommodating surface and a second accommodating surface which are perpendicular to the first and second rotation axes; The sealing portion increases the airtightness of at least one of a first gap between the first accommodating surface and an end face of the first rotor facing the first accommodating surface, a second gap between the first accommodating surface and an end face of the second rotor facing the first accommodating surface, a third gap between the second accommodating surface and an end face of the first rotor facing the second accommodating surface, and a fourth gap between the second accommodating surface and an end face of the second rotor facing the second accommodating surface.

2. The claw compressor as described in claim 1, wherein the sealing portion comprises a first tip seal arranged in a first groove portion formed in the end face of the first rotor facing the first accommodating surface, a second tip seal arranged in a second groove portion formed in the end face of the second rotor facing the first accommodating surface, and a third tip seal arranged in a third groove portion formed in the end face of the first rotor facing the second accommodating surface, and a discharge port is formed in an area of ​​the second accommodating surface facing the end face of the second rotor, for discharging steam compressed between the first claw portion and the first recess or between the second claw portion and the second recess.

3. A claw compressor as claimed in claim 2, further comprising a fluid supply port for supplying a fluid for lowering the temperature of said steam to at least one of said first groove portion, said second groove portion and said third groove portion.

4. A claw compressor as described in claim 2, further comprising a fluid supply port which supplies a fluid to the compression chamber for lowering the temperature of the steam compressed between the first claw portion and the first recess or between the second claw portion and the second recess, the fluid supply port supplying a fluid from the second accommodating surface to the fourth gap.

5. A claw compressor as described in claim 1, comprising a fluid supply port which supplies to the compression chamber a fluid for lowering the temperature of steam compressed between the first claw portion and the first recess or between the second claw portion and the second recess, wherein the sealing portion has a first tip seal arranged in a first groove portion formed in the end face of the first rotor facing the first accommodating surface, and a second tip seal arranged in a second groove portion formed in the end face of the second rotor facing the first accommodating surface, and the fluid supply port supplies fluid from the second accommodating surface to the third gap and the fourth gap.

6. A claw compressor as described in claim 1, further comprising a fluid supply port which supplies to the compression chamber a fluid for lowering the temperature of steam compressed between the first claw portion and the first recess or between the second claw portion and the second recess, the compression portion having a connecting surface which connects the first storage surface and the second storage surface and is arranged to surround the compression chamber, and the fluid supply port which supplies fluid from the connecting surface to the compression chamber along a radial direction perpendicular to the first rotation axis and the second rotation axis.

7. A claw compressor as described in claim 1, further comprising a fluid supply port which supplies a fluid for lowering the temperature of steam compressed between the first claw portion and the first recess or between the second claw portion and the second recess to the compression chamber via an internal flow passage formed inside the second rotor.

8. A claw compressor as described in claim 7, wherein the compression chamber has a connecting surface that connects the first storage surface and the second storage surface and is arranged to surround the compression chamber, and the fluid supply port supplies fluid to a gap between the second rotor and the connecting surface.

9. A claw compressor as described in claim 1, wherein a first groove portion is formed in an end face of the first rotor facing the first accommodating surface, a second groove portion is formed in an end face of the second rotor facing the first accommodating surface, a third groove portion is formed in an end face of the first rotor facing the second accommodating surface, and a fourth groove portion is formed in an end face of the second rotor facing the second accommodating surface, and the seal portion has a fluid supply port for supplying a fluid for lowering a temperature of the steam to the first groove portion, the second groove portion, the third groove portion, and the fourth groove portion.

10. A claw compressor as claimed in any one of claims 3 to 9, further comprising an adjusting valve for adjusting the amount of fluid supplied from the fluid supply port to the compression chamber in accordance with the temperature of the fluid discharged from the compression chamber.

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