JP7485093B2 - Fluid Machinery - Google Patents

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on Patent Application No. 2021-4504 filed in Japan on January 14, 2021, and the contents of the original application are incorporated by reference in their entirety.

The disclosure in this specification relates to fluid machinery.

Patent document 1 discloses a fluid machine used as a negative pressure pump. Patent document 2 discloses a through vane type fluid machine.

JP 2012-87700 A Japanese Patent Application Laid-Open No. 3-217683

The fluid machine of Patent Document 1 has room for improvement in terms of reducing bearing problems caused by differential pressure.

In a through-vane type fluid machine such as that described in Patent Document 2, there is room for improvement in terms of reducing friction between the rotor and the members that slide relative to the rotor.

The purpose of the disclosure in this specification is to provide a fluid machine in which the quality of the bearing portion can be ensured.

The purpose of the disclosure in this specification is to provide a through vane type fluid machine that can suppress mechanical losses.

The various aspects disclosed in this specification employ different technical means to achieve their respective objectives. The claims and the reference symbols in parentheses in this section are merely examples showing the correspondence with the specific means described in the embodiments described below as one aspect, and do not limit the technical scope.

One of the disclosed fluid machines includes a housing (32, 24, 31; 124; 132), a motor section (2), a pump rotor (6; 106; 206) driven by a driving force applied by the motor section and rotating inside the housing, a suction chamber (71) provided inside the housing in which a working fluid from the outside flows into the inside of the housing via an external suction passage (70), a compression chamber (73) in which the working fluid supplied through the suction chamber is compressed and discharged as the pump rotor rotates, a motor chamber (241) provided inside the housing and isolated from the suction chamber so that the working fluid does not flow, and in which the motor section is accommodated, and a compressor (206) for transmitting the driving force of the motor section to the pump rotor. and a bearing portion (212) rotatably supporting a shaft (21) reaching the suction chamber, the bearing portion having a portion exposed to the suction chamber. The bearing portion is provided with a bearing support portion (34) supporting the bearing portion, a cylindrical wall portion (341) extending from the bearing support portion toward the compression chamber side and covering the bearing portion radially outward from the bearing portion, and a communicating passage (340) allowing the working fluid to move between an area in contact with the bearing portion and an area radially outward from the cylindrical wall portion. The pump rotor is provided with a drive shaft portion (21, 37, 373) which drives the pump rotor and a member (35) through which the drive shaft portion penetrates, and the drive shaft seal portion is provided to contact and seal the drive shaft portion and a member (35) through which the drive shaft portion penetrates, and the drive shaft seal portion is held between the member through which the drive shaft portion penetrates and the compression chamber side end face of the cylindrical wall portion .

In this fluid machine, the working fluid drawn into the suction chamber from the outside comes into contact with the bearing, so that a large differential pressure is unlikely to be applied to the bearing. This makes it possible to prevent grease leakage from the bearing due to an excessive differential pressure. Therefore, the quality of the bearing can be ensured with this fluid machine.
One of the disclosed fluid machines includes a housing (32, 24, 31; 124; 132), a motor section (2), a pump rotor (6; 106; 206; 506) driven by a driving force applied by the motor section and rotating inside the housing, a suction chamber (71) provided inside the housing and into which a working fluid from the outside flows into the inside of the housing via an external suction passage (70), a compression chamber (73) that compresses and discharges the working fluid supplied through the suction chamber as the pump rotor rotates, a motor chamber (241) that accommodates the motor section, and a bearing section (212) that rotatably supports a shaft (21) that transmits the driving force of the motor section to the pump rotor, the bearing section having a portion exposed to the suction chamber. and a vane (4, 5; 4; 104) which slides in the radial direction of the pump rotor and a support part (372; 1372) which connects a supported part (61) of the pump rotor to the shaft, the compression chamber being defined in the circumferential direction by the vane between the inner surface (32a) of the housing and the outer surface (6c) of the pump rotor, the support part and the supported part being connected together so as to be able to move axially and/or tilt relatively, and the support part is provided with a gap part, inside the part in contact with the supported part, in which the vane which extends in the radial direction of the pump rotor through the central axis of the pump rotor can slide.

1 is a vertical sectional view of a fluid machine according to a first embodiment. FIG. 4 is a partial cross-sectional view showing the configuration of an external intake passage. FIG. 4 is a cross-sectional view of a suction chamber case that forms a suction chamber. 1 is a cross-sectional view of a pump rotor, vanes, etc., taken perpendicular to the shaft axis. FIG. 4 is an explanatory diagram of a theoretical formula for pulsation damping. FIG. 4 is a vertical cross-sectional view showing a first modified example of the fluid machine. FIG. 11 is a vertical cross-sectional view showing a second modified example of the fluid machine. FIG. 11 is a vertical cross-sectional view showing a third modified example of the fluid machine. FIG. 10 is a vertical cross-sectional view showing a fourth modified example of the fluid machine. FIG. 13 is a vertical cross-sectional view showing a fifth modified example of the fluid machine. FIG. 6 is a vertical sectional view of a fluid machine according to a second embodiment. 4 is a cross-sectional view of a pump rotor, vanes, etc., taken perpendicular to the shaft axis. FIG. FIG. 2 is a plan view of the pump rotor as viewed toward the motor unit side. 14 is a longitudinal sectional view of the pump rotor taken along the line XIV-XIV in FIG. 13. FIG. 4 is a plan view of the pump rotor as viewed toward the discharge chamber side. FIG. FIG. 2 is a longitudinal sectional view of a fluid machine including a longitudinal sectional view of a driving pin. FIG. FIG. 11 is a cross-sectional view of a pump rotor, vanes, etc. of a third embodiment, taken perpendicular to the shaft axis. FIG. 2 is a vertical cross-sectional view of a pump rotor, vanes, etc. FIG. 10 is a vertical sectional view of a fluid machine according to a fourth embodiment. 4 is a diagram showing the positional relationship between the inner circumferential surface of the cylinder and the tip of the vane. FIG. FIG. 23 is an enlarged view of a portion XXIII of FIG. 22. FIG. 13 is a vertical cross-sectional view of a fluid machine according to a fifth embodiment. 4 is a cross-sectional view of a pump rotor, vanes, etc., taken perpendicular to the shaft axis. FIG. FIG. 2 is a plan view of the pump rotor as viewed toward the motor unit side. FIG. 27 is a longitudinal sectional view of the pump rotor taken along the cross section XXVII-XXVII of FIG. 26. FIG. 4 is a plan view of the pump rotor as viewed toward the discharge chamber side. FIG. 13 is a vertical cross-sectional view of a fluid machine according to a sixth embodiment. FIG. 13 is a vertical cross-sectional view of a fluid machine according to a seventh embodiment. FIG. 13 is a vertical cross-sectional view of a fluid machine according to an eighth embodiment.

Below, multiple forms for implementing the present disclosure are described with reference to the drawings. In each form, parts corresponding to matters described in the preceding form may be given the same reference numerals, and duplicated descriptions may be omitted. In cases where only a portion of the configuration is described in each form, other forms previously described may be applied to other portions of the configuration. Not only combinations of parts that are specifically specified as being possible in each embodiment are possible, but also partial combinations of embodiments may be possible even if not specified, provided that no particular hindrance is caused to the combination.

First Embodiment
A first embodiment disclosing an example of a fluid machine will be described with reference to Figs. 1 to 10. The fluid machine includes a pump unit that compresses a fluid. The fluid machine 1 disclosed in the first embodiment can compress a liquid, a gas, a gas-liquid mixed fluid, or the like used as a working fluid and cause it to flow out to the outside. For example, the working fluid is air, water, various refrigerants, or the like. The fluid machine 1 is not, for example, a device that drives a working fluid in a closed loop circuit, but rather supplies the working fluid flowing out from the fluid machine 1 to the open outside.

The fluid machine 1 is a vane-type fluid machine equipped with vanes that extend through the pump rotor 6 and slide radially. The fluid machine 1 is preferably an oil-less device that can function normally without receiving oil from the outside. This fluid machine 1 does not require auxiliary devices such as an oil separator. The fluid machine 1 can also be used as an air pressure source that supplies clean air, such as medical air or factory air. Below, an example of the fluid machine 1 using air as the working fluid is described.

The configuration of the fluid machine 1 will be described with reference to Figure 1. In Figure 1, RD indicates the radial direction, AD indicates the axial direction of the shaft 21, MS indicates the motor section 2 side, and BS indicates the discharge chamber 75 side. The fluid machine 1 shown in Figure 1 includes a motor section 2, a pump section 3, etc. The pump section 3 includes a compression chamber 73 that is circumferentially defined by a cylinder 32, a pump rotor 6, and a number of vanes, etc. The pump section 3 forms an area in the fluid machine 1 through which the working fluid flows, excluding the motor section 2. The compression chamber 73 compresses and discharges the working fluid supplied via the suction chamber 71 as the pump rotor 6 rotates.

The fluid machine 1 has a housing formed integrally from multiple members. The housing of the fluid machine 1 includes a motor yoke 24, a suction chamber case 31, a cylinder 32, and a cover 33. The motor yoke 24 and the suction chamber case 31 are joined together to form part of the housing. The suction chamber case 31 and the motor yoke 24 are fixed together by bolting, welding, or the like.

The suction chamber case 31 includes a bearing support 34. The bearing support 34 includes a portion that supports the second bearing 212 and an annular plate portion that separates the motor chamber 241 and the suction chamber 71. The suction chamber case 31 and the cylinder 32 are integrally formed via the first plate 35. The suction chamber case 31 is integral with the first plate 35 in a sealed state, with the end of the cylindrical body being connected to the first plate 35 via the gasket 11. The cylinder 32 is integral with the first plate 35 in a sealed state, with the end of the cylindrical body being connected to the first plate 35 via the gasket 12. The gaskets 11 and 12 prevent the working fluid from flowing out of the pump chamber to the outside air and the inflow of gas and foreign matter from the outside air.

The cylinder 32 and the cover 33 are integrally formed via the second plate 36. The cylinder 32 is integral with the second plate 36 in a sealed state, with the end of the cylindrical body being connected to the second plate 36 via the gasket 13. The cover 33 is integral with the second plate 36 in a sealed state, with the end of the cylindrical body being connected to the second plate 36 via the gasket 14. The suction chamber case 31, the first plate 35, the cylinder 32, the second plate 36 and the cover 33 are fixed, for example, by bolting or welding. These members are installed so as to be stacked in the axial direction AD of the shaft 21 to form a housing.

The suction chamber case 31, first plate 35, cylinder 32, second plate 36, and cover 33 are installed so that their respective outer walls are exposed to the atmosphere. These components may be configured so that at least a portion of them is made of a metal with good thermal conductivity. These components only need to be configured so that at least a portion of them is exposed to the atmosphere. With this configuration, heat generated in the sliding parts caused by the rotation of the pump rotor 6 is diffused through the outer wall and released into the atmosphere outside the fluid machine 1.

The suction chamber case 31 is part of the housing of the fluid machine 1. The suction chamber case 31 forms a suction chamber 71 inside into which the working fluid is sucked. The suction chamber case 31 is provided with an external suction passage 70 that draws the working fluid flowing out from an external device into the suction chamber 71. The external suction passage 70 is a passage that radially penetrates the suction chamber case 31 and is an inlet that takes in the working fluid into the interior of the fluid machine 1.

The external suction passage 70 includes a first passage section 70a and a second passage section 70b located downstream of the first passage section 70a. The first passage section 70a is formed in a mortar shape in which the passage cross-sectional area is largest at the most upstream section and the passage cross-sectional area becomes smaller as it moves downstream. The first passage section 70a formed in this manner contributes to suppressing fluid noise during suction while suppressing suction resistance. In this specification, the passage cross-sectional area is the area of a cross section perpendicular to the passage axis direction. The passage cross-sectional area of the second passage section 70b is smaller than the average passage cross-sectional area of the first passage section 70a and is equivalent to the passage cross-sectional area at the most downstream of the first passage section 70a. The passage cross-sectional area of the second passage section 70b is set to S1. The external suction passage 70 constitutes a passage in which the passage cross-sectional area is smaller downstream than upstream.

The introduction member 8, which forms a passage communicating with the external suction passage 70, is fixed integrally to the suction chamber case 31. The introduction member 8 is connected to a pipe that forms a passage leading to an external device. As shown in FIG. 2, the introduction member 8 has a plurality of fine holes 80 and a chamber 81 formed downstream of the plurality of fine holes 80. The passage formed by the fine holes 80 has a passage cross-sectional area set to S0, which is smaller than S1. The chamber 81 is formed to have a passage cross-sectional area larger than the fine holes 80 and the external suction passage 70. The working fluid from the external device is divided by the fine holes 80 and then diffused into the chamber 81, and is further greatly narrowed in the first passage portion 70a and the second passage portion 70b before spreading in the suction chamber 71. In other words, the fluid machine 1 suppresses pressure pulsation on the suction side by repeatedly contracting and expanding when the working fluid flows through the introduction member 8, the external suction passage 70, and the suction chamber 71. In addition, the plurality of fine holes 80 suppresses clogging of the external suction passage 70 by foreign matter from the outside.

As shown in Figure 3, the cross-sectional area of the suction chamber 71 is set to S2 immediately after the working fluid flows into the external suction passage 70. The cross-sectional area S2 is the cross-sectional area of a plane perpendicular to the radial direction RD. This cross section is the cross section of the suction chamber 71 at the position where the length in the axial direction AD is the longest. The cross section with area S2 and the cross section with area S1 are parallel to each other.

Figure 5 shows the theoretical formula R and model of theoretical transmission loss related to pulsation attenuation. Transmission loss is also called pulsation attenuation. The theoretical formula can be calculated from the throttling ratio m, which is the ratio of the passage cross-sectional area S2 to the passage cross-sectional area S1, and the length l of the suction chamber. In order to attenuate low frequencies near a pulsation frequency of 250 Hz, it is preferable to form the fluid machine 1 so that the throttling ratio m and length l are large. Furthermore, in order to obtain a damping effect of 5 dB or more near a frequency of 250 Hz, it is preferable to form the fluid machine 1 so that the throttling ratio m is 16 or more.

In addition, the passage cross-sectional area S0 of the fine hole 80 is preferably small to suppress suction pulsation, but there is a trade-off with pressure loss. Since it is preferable to keep the pressure loss during suction to 10 kPa or less, in the fluid machine 1, the passage cross-sectional area of the external suction passage 70 is set to achieve this pressure loss.

As shown in FIG. 3, a filter 15 is provided inside the suction chamber case 31, between the external suction passage 70 and the shaft 21. The filter 15 is provided in the suction side area of the suction chamber 71. The filter 15 is a device that captures foreign matter contained in the working fluid upstream of the compression chamber 73, and prevents performance from being impaired due to operational malfunctions, corrosion, etc. caused by foreign matter. The filter 15 is made of a porous material. The filter 15 is made of a filter material such as a woven or nonwoven fiber fabric. The filter 15 includes, for example, a mesh portion set to an opening rate that prevents foreign matter from passing through, and a frame portion that supports the mesh portion. The mesh portion is made of, for example, polypropylene or nylon 66, and the frame portion is made of, for example, polypropylene or nylon 66 reinforced with glass fiber.

As shown in Figure 3, the fluid machine 1 has a motor terminal 2a that supplies power to the motor section 2. The motor terminal 2a is provided in the suction chamber case 31, radially outward of the suction chamber 71 and the second bearing section 212.

The first plate 35 is provided with a compression chamber introduction passage 72 that connects the suction chamber 71 and the compression chamber 73. The compression chamber introduction passage 72 is a passage that penetrates the first plate 35 in the axial direction AD, and is a passage that draws the working fluid from the suction chamber 71 to the compression chamber 73. The first plate 35 is a passage forming member in which the compression chamber introduction passage 72 is provided. As shown in FIG. 4, the compression chamber introduction passage 72 is elongated in the circumferential direction and forms an opening that is shaped to follow the inner circumferential surface 32a of the cylinder 32.

The suction chamber 71 is formed to include an intake side area and an outflow side area. The intake side area is an area that occupies half of the intake chamber 71 on the side where the external intake passage 70 is located relative to the shaft 21. The outflow side area is an area that occupies half of the intake chamber 71 on the opposite side to the intake side area. The intake side area and the outflow side area may be configured to have the same volume, or one may be configured to have a larger volume than the other. The compression chamber introduction passage 72 is a passage provided in a position facing the outflow side area of the intake chamber 71. In other words, when viewed in the axial direction of the shaft 21, the compression chamber introduction passage 72 and the external intake passage 70 are located in two opposing areas divided by the shaft 21 between them. When viewed in the axial direction of the shaft 21, the intake side area is an area corresponding to the entire side of the intake chamber 71 shown in FIG. 3 on the side where the external intake passage 70 is located from the central axis of the shaft 21. The outflow side area, when viewed in the axial direction of the shaft 21, corresponds to the entire area of the suction chamber 71 shown in Figure 3 on the side where the compression chamber introduction passage 72 is located from the central axis of the shaft 21. The external suction passage 70 and the compression chamber introduction passage 72, which are positioned in this way, contribute to the working fluid diffusing in the suction chamber 71 and circulating over a wide area.

The compression chamber introduction passage 72 is located in an area including a range rotated 180 degrees or more in the circumferential direction CD around the shaft 21 in the outflow side area. The compression chamber introduction passage 72 is a passage that penetrates a wall portion facing an area including this range in the outflow side area. It is preferable that the external suction passage 70 and the compression chamber introduction passage 72 are provided in such a positional relationship so that the working fluid circulates over a wide area in the suction chamber 71. The working fluid that flows into the suction chamber 71 flows around the shaft 21, passes the shaft 21, moves to the outflow side area, changes its flow in the axial direction, and reaches the compression chamber introduction passage 72. When the suction chamber 71 is a sector shape having a circumferential length with a central angle of less than 180 degrees around the shaft 21, the central angle between the suction side area and the outflow side area is less than 90 degrees. When the suction chamber 71 is a ring shape centered on the shaft 21 as viewed in the axial direction, the suction side area and the outflow side area are semicircular with a central angle of less than 180 degrees.

The cover 33 comprises a base portion and a cylindrical wall that protrudes in the axial direction AD from the peripheral portion of the base portion to surround the base portion. The base portion of the cover 33 is provided with a discharge port 76 that penetrates in the axial direction AD. The discharge port 76 is an external outflow passage that discharges fluid to the outside of the fluid machine 1. The cylindrical wall of the cover 33 contacts the second plate 36 and supports the second plate 36 by sandwiching it between the cylinder 32. The space surrounded by the cover 33 and the second plate 36 defines a discharge chamber 75 that communicates with the discharge port 76.

A filter 16 is provided in the discharge chamber 75. The filter 16 is a member capable of collecting abrasion powder and the like generated by sliding between a fixed member and the pump rotor 6. The filter 16 is made of a porous material. The filter 16 is a member formed of a porous material into a predetermined shape. The filter 16 is made of a filtering material such as a woven or nonwoven fiber fabric.

The second plate 36 is provided with a discharge chamber introduction passage 74 that connects the discharge chamber 75 and the compression chamber 73. The discharge chamber introduction passage 74 is a passage that penetrates the second plate 36 in the axial direction AD and is a passage that discharges the working fluid from the compression chamber 73 to the discharge chamber 75. As shown in FIG. 4, the discharge chamber introduction passage 74 is elongated in the circumferential direction and forms an opening that is shaped to follow the inner circumferential surface 32a of the cylinder 32. The discharge chamber introduction passage 74 and the compression chamber introduction passage 72 are provided so that the center axis of the pump rotor 6 is located between them and they face each other in the radial direction.

The cylinder 32, pump rotor 6 and vanes form a compression mechanism for drawing in, compressing and discharging the working fluid.

As shown in Figure 4, a cylindrical pump rotor 6 is provided inside the cylindrical cylinder 32. A plurality of compression chambers 73 are formed between the outer peripheral surface 6c of the pump rotor 6 and the inner peripheral surface 32a of the cylinder 32. The central axis of the pump rotor 6 is provided at a position offset from the central axis of the cylinder 32. With this configuration, the pump rotor 6 rotates at a position offset to one side inside the cylinder 32. A plurality of vanes 4 are slidably attached to the pump rotor 6.

The vane 4 slides radially while fitted into a slit 6s formed in the pump rotor 6. The radially outer tip of the vane 4 slides against the inner circumferential surface 32a of the cylinder 32 as the pump rotor 6 rotates.

Each of the multiple compression chambers 73 is formed between adjacent vanes 4 in the circumferential direction. The compression chambers 73 are partitioned by the vanes 4, the inner peripheral surface 32a of the cylinder 32, the outer peripheral surface 6c of the pump rotor 6, the first plate 35, and the second plate 36. The space between the outer peripheral surface 6c and the inner peripheral surface 32a is narrower in the portion where the outer peripheral surface 6c is closer to the inner peripheral surface 32a than in other portions. A compression chamber 73 narrower than the other portions is formed between the narrow outer peripheral surface 6c and the inner peripheral surface 32a. The fluid machine 1 has three compression chambers 73 arranged in the circumferential direction. The fluid machine 1 has a narrow compression chamber 73 and a wide compression chamber 73 located on the opposite side to the narrow compression chamber 73. The narrow compression chamber 73 is formed in the portion where the outer peripheral surface 6c is close to the inner peripheral surface 32a. The wide compression chamber 73 is formed in the portion where the outer peripheral surface 6c is far away from the inner peripheral surface 32a. The multiple compression chambers 73 move circumferentially as the pump rotor 6 rotates.

The pump rotor 6 has a supported portion 61 that is supported in contact with the connecting portion 37. The connecting portion 37 is a member that connects the pump rotor 6 and the shaft 21. The supported portion 61 is a cylindrical portion that forms an inner circumferential surface that penetrates in the axial direction and has a predetermined axial length. The connecting portion 37 is press-fitted against the inner circumferential surface of the supported portion 61, and the connecting portion 37 and the supported portion 61 are fitted together.

The pump rotor 6 is provided with a slit 6s into which the vane 4 is fitted. The slit 6s is a plate-like body that has an elongated cross-sectional shape that extends in a direction intersecting the radial direction of the pump rotor 6 and extends in the axial direction. The tip of the vane 4 is formed with a curved surface.

The pump rotor 6 is provided with an engagement hole portion that forms a hole penetrating in the axial direction. As shown in FIG. 1 and FIG. 4, the engagement hole portion is in contact with the inserted driving pin 64. The driving pin 64 engages with the engagement hole portion 6d to support the pump rotor 6. The driving pin 64 has a motor side portion, which is an end portion on the motor unit 2 side, fixed to the base portion 373. The base portion 373 is coaxially connected to the connecting portion 37 and is provided coaxially with the shaft 21. The base portion 373 and the connecting portion 37 rotate together with the shaft 21 as the shaft 21 rotates. The base portion 373 drives the pump rotor 6 via the driving pin 64. With this configuration, the base portion 373, the connecting portion 37, and the pump rotor 6 rotate together with the shaft 21. The shaft 21 is a driving portion that provides a rotational driving force to the pump rotor 6.

The suction chamber case 31, cylinder 32, first plate 35, second plate 36, and cover 33 can be made of metal, resin, etc. The pump rotor 6 is made of a stainless steel material. The first plate 35 and the second plate 36 have a polytetrafluoroethylene coating on the sliding surface that slides against the pump rotor 6. Alternatively, the pump rotor 6 may be made of carbon, and the first plate 35 and the second plate 36 may be made of a stainless steel material. This configuration contributes to ensuring sliding performance under oil-free conditions where no lubricating oil is supplied from the outside.

The cylinder 32 is part of the housing of the fluid machine 1. The cylinder 32 is made of a stainless steel material. The vane 4 is preferably made of carbon. This configuration helps to reduce wear and seizure between the tip of the vane 4 and the inner surface of the cylinder 32, and is useful in a fluid machine 1 used under oil-free conditions.

The motor section 2 is integrally provided on the side opposite the cylinder 32 side of the suction chamber case 31. The suction chamber 71 is formed inside the suction chamber case 31. The motor yoke 24 is integral with the suction chamber case 31 in a sealed state, with the end of the cylindrical body being connected to the suction chamber case 31 via a gasket 10. The motor yoke 24 is part of the housing of the fluid machine 1.

The motor section 2 has a stator, a motor rotor 22, a shaft 21, etc., which are provided inside the motor yoke 24. The motor section 2 is housed in a motor chamber 241. The motor chamber 241 is partitioned by the bearing support section 34 and the second bearing section 212 so as to be isolated from the suction chamber 71. The motor chamber 241 is maintained at atmospheric pressure because it is isolated from the flow path of air, which is the working fluid, from the suction chamber 71 to the discharge port 76. Therefore, there is no active inflow of outside air into the motor chamber 241, and the fluid machine 1 contributes to suppressing corrosion of the motor section 2 due to moisture caused by the outside air. In addition, since no pressure difference occurs between the pump rotor side end surface 212a and the motor side end surface 212b of the second bearing section 212, grease leakage from the second bearing section 212 can be suppressed.

Various motors, such as a brushed motor or a brushless motor, can be used as the motor section 2. The shaft 21 is rotatably supported by a first bearing section 211 provided inside the motor yoke 24 and a second bearing section 212 supported by the bearing support section 34. The first bearing section 211 supports one end shaft section 21a of the shaft 21. The second bearing section 212 supports a portion of the shaft 21 closer to the motor rotor 22 than the other end shaft section 21b. The second bearing section 212 is a bearing section located inside the suction chamber case 31 and rotatably supports the shaft 21, which transmits the driving force of the motor section 2 to the pump rotor 6.

The stator, motor rotor 22, etc. are located in a motor chamber 241 formed inside the motor yoke 24. The motor chamber 241 is formed by an internal space surrounded by the motor yoke 24, the bearing support portion 34, and the second bearing portion 212. The motor chamber 241 is a space portion adjacent to the suction chamber 71 via the bearing support portion 34. The bearing support portion 34 contacts the outer periphery of the second bearing portion 212 and supports the second bearing portion 212.

The second bearing portion 212 has a pump rotor side end face 212a located on the pump rotor 6 side and a motor side end face 212b located on the motor rotor 22 side. The pump rotor side end face 212a and the motor side end face 212b are located opposite each other in the axial direction of the shaft 21, and each form an annular surface around the axis of the shaft 21. The pump rotor side end face 212a is exposed to the suction chamber 71 and can come into contact with the working fluid flowing through the suction chamber 71. The motor side end face 212b is not exposed to the suction chamber 71 and does not come into contact with the working fluid. The second bearing portion 212 has a portion exposed to the suction chamber 71, including the pump rotor side end face 212a.

The shaft 21 is rotated by the driving force provided by the motor section 2. The connecting section 37 and the pump rotor 6 are separate components. The connecting section 37, the pump rotor 6 and the shaft 21 are arranged coaxially and are rotated together. The other end shaft section 21b of the shaft 21 is connected to the connecting section 37. The connecting section 37 has a one-side connecting section 371 that connects to the shaft 21 and a pair of other-side support sections 372 that support the pump rotor 6. The one-side connecting section 371 is located on the motor section 2 side of the connecting section 37. The pair of other-side support sections 372 are located on the discharge chamber 75 side of the connecting section 37.

The other end shaft portion 21b is tightly connected to the inner wall surface of the one-side connecting portion 371. The one-side connecting portion 371 is a cylindrical portion that encases the other end shaft portion 21b from the outside and is fixed coaxially to the other end shaft portion 21b. The one-side connecting portion 371 is located in the suction chamber 71.

The central axis of the shaft 21 is the rotation axis of the pump rotor 6. The shaft 21 is a drive shaft portion that rotates the pump rotor 6 via the drive pin 64.

The pump rotor 6 rotates in the cylinder 32 with an arc-shaped seal portion closest to the inner circumferential surface 32a and a spaced portion far removed from the inner circumferential surface 32a formed on the outer circumferential surface 6c. The fluid machine 1 forms a narrow compression chamber 73 on the arc-shaped seal portion side and a wide compression chamber 73 on the spaced portion side. The narrow compression chamber 73 moves in the rotational direction while the vane 4 rotates, and expands as it approaches the spaced portion, changing into a wide compression chamber 73. The wide compression chamber 73 moves in the rotational direction while the vane 4 rotates, and shrinks as it approaches the arc-shaped seal portion, changing into a narrow compression chamber 73. In this way, each compression chamber 73 changes so that its volume gradually decreases as it approaches the discharge chamber introduction passage 74 during one rotation of the vane 4. The air supplied to the compression chamber 73 through the compression chamber introduction passage 72 is compressed, and this air is discharged from the discharge chamber introduction passage 74 to the discharge chamber 75.

In the fluid machine 1, the air, which is the working fluid, flows down through the external suction passage 70, the suction chamber 71, the compression chamber introduction passage 72, and the compression chamber 73 in that order. The air flows down from the compression chamber 73 through the discharge chamber introduction passage 74 and the discharge chamber 75 in that order, and then flows out to the outside through the discharge port 76. As the air flows through this fluid path, it cools each part, and contributes to effectively releasing heat, especially from the sliding parts.

<First Modification of Fluid Machine 1>
6 , the fluid machine 1 of the first modified example includes a first seal portion 17 that contacts and seals with the shaft 21 and the bearing support portion 34. The first seal portion 17 contacts the outer circumferential surface of the shaft 21, and is sandwiched between a pump rotor side end face 212a of the second bearing portion 212 and the bearing support portion 34.

The first seal portion 17 prevents the working fluid in the suction chamber 71 from passing between the outer circumferential surface of the shaft 21 and the inner circumferential surface of the second bearing portion 212 and entering the motor chamber 241. The first seal portion 17 prevents the working fluid in the suction chamber 71 from passing between the bearing support portion 34 and the second bearing portion 212 and entering the motor chamber 241. The first seal portion 17 is formed of a fluorine-containing resin, a rubber packing, or the like.

<Second Modification of Fluid Machine 1>
7 , the fluid machine 1 of the second modified example includes a second seal portion 18 that contacts and seals a connecting portion 37 and a first plate 35. Each portion of the connecting portion 37 that contacts the second seal portion 18 is included in a drive shaft portion that drives the pump rotor 6. The second seal portion 18 contacts an outer circumferential surface of the drive shaft portion that penetrates the first plate 35, and contacts an inner circumferential surface that forms a through hole 350 in the first plate 35.

The second seal 18 prevents the working fluid in the compression chamber 73 from leaking into the suction chamber 71 through the gap between the pump rotor 6 and the first plate 35. The second seal 18 prevents the working fluid from moving between the inside of the cylinder 32 and the suction chamber 71 without passing through the compression chamber introduction passage 72. The second seal 18 is formed from a fluorine-containing resin, a rubber packing, or the like.

<Third Modification of Fluid Machine 1>
As shown in Fig. 8, the fluid machine 1 of the third modified example includes a third seal portion 19 that contacts and seals the pump rotor 6 and the first plate 35. The third seal portion 19 is sandwiched between the first plate 35 and the pump rotor 6. The third seal portion 19 seals between a discharge chamber side surface 35a of the first plate 35 and a motor side surface 6b of the pump rotor 6. The third seal portion 19 seals between the first plate 35 and the pump rotor 6 while the pump rotor 6 and the first plate 35 are able to slide relative to each other.

The third seal 19 prevents the working fluid in the compression chamber 73 from leaking into the suction chamber 71 through the gap between the pump rotor 6 and the first plate 35. The third seal 19 prevents the working fluid from passing between the inside of the cylinder 32 and the suction chamber 71. The third seal 19 is formed from a fluorine-containing resin, a rubber packing, or the like.

<Fourth Modification of Fluid Machine 1>
As shown in Fig. 9, the fluid machine 1 of the fourth modification includes a cylindrical wall portion 341 extending from the bearing support portion 34 toward the compression chamber side. The cylindrical wall portion 341 stands at a position closer to the compression chamber than the pump rotor side end surface 212a of the second bearing portion 212, and covers the second bearing portion 212 radially outward from the second bearing portion 212. The cylindrical wall portion 341 is provided with a communication passage 340 through which the working fluid can travel between an area in contact with the pump rotor side end surface 212a and an area radially outward from the cylindrical wall portion 341. The communication passage 340 may be formed by an axial end surface of the cylindrical wall portion 341, or may be configured to penetrate the cylindrical wall portion 341. The cylindrical wall portion 341 functions as a shielding wall that prevents foreign matter from coming into contact with the second bearing portion 212 and causing a malfunction due to the flow of the working fluid flowing through the suction chamber 71. Furthermore, when the working fluid is air, the cylindrical wall portion 341 can prevent the second bearing portion 212 from being exposed to moisture contained in the air drawn into the suction chamber 71 .

<Fifth Modification of Fluid Machine 1>
10, the fluid machine 1 of the fourth modified example includes a motor case 124, a suction chamber case 131, a cylinder 32, and a cover 33 to form a housing. The motor case 124 and the suction chamber case 131 are joined together via a bearing support member 134. The bearing support member 134 includes a support portion 34a that supports the second bearing portion 212, and an annular plate portion that extends radially outward from the outer periphery of the support portion 34a. The annular plate portion of the bearing support member 134 is joined to the motor case 124 and the suction chamber case 131 in a state where it is sandwiched between them.

The effects of the fluid machine 1 of the first embodiment will be described. The fluid machine 1 includes a motor section 2, a pump rotor 6 that rotates inside the housing by the driving force of the motor section 2, and a suction chamber 71 into which the working fluid flows through an external suction passage 70. The fluid machine 1 includes a compression chamber 73 that compresses and discharges the working fluid supplied through the suction chamber 71, a motor chamber 241 that houses the motor section, and a bearing section. The motor chamber 241 is provided inside the housing and is isolated from the suction chamber 71 so that the working fluid does not flow. The bearing section rotatably supports the shaft 21 that transmits the driving force of the motor section 2 to the pump rotor 6. The bearing section has a portion that is exposed to the suction chamber 71.

According to this fluid machine 1, the working fluid sucked into the suction chamber 71 from the outside comes into contact with the bearing section. This action makes it difficult for a large differential pressure to be applied to the bearing section, and it is possible to prevent situations in which grease leakage or the like occurs at the bearing section due to excessive differential pressure. This fluid machine 1 can ensure the quality of the bearing section. Furthermore, since the motor chamber 241 is configured so that the working fluid does not flow through it, it contributes to preventing corrosion of each part of the motor section 2.

The compression chamber introduction passage 72 is provided at a position facing the outflow area of the suction chamber 71. As a result, the compression chamber introduction passage 72 and the external suction passage 70 are positioned with the shaft 21 between them, which contributes to suppressing suction pulsation noise while preventing the fluid machine 1 from becoming larger.

The compression chamber introduction passage 72 is located in an area of the outflow side area that includes a range obtained by rotating the external suction passage 70 in the circumferential direction CD by 180 degrees or more around the shaft 21. This allows the distance between the compression chamber introduction passage 72 exposed to the suction chamber 71 and the external suction passage 70 to be set as large as possible. This makes it possible to provide a fluid machine 1 that contributes to suppressing suction pulsation noise while preventing the machine from becoming too large.

The fluid machine 1 is a device used under oil-free conditions where there is no lubricating oil supplied from the outside. This makes it possible to provide a fluid machine 1 that can suppress mechanical loss between the pump rotor 6 and surrounding components due to the displaceable characteristics of the pump rotor 6, and also contributes to preventing seizure when no oil is supplied.

Second Embodiment
The second embodiment will be described with reference to Figures 11 to 18. A fluid machine 101 of the second embodiment is different from the first embodiment in that it is a through vane type fluid machine. The configurations, actions, and effects of the second embodiment that are not specifically described are the same as those of the above-mentioned embodiments, and only the differences will be described below.

The fluid machine 101 is equipped with vanes that extend through the pump rotor 106 via the central axis of the pump rotor 106 and slide in the radial direction of the pump rotor 106. The fluid machine 101 is preferably an oil-less device that can function normally without receiving oil from the outside. This fluid machine 101 does not require ancillary devices such as an oil separator. The fluid machine 101 can also be used as an air pressure source that supplies clean air, such as medical air or factory air. Below, an example of the fluid machine 101 using air as the working fluid will be described.

The configuration of the fluid machine 101 will be described with reference to Figure 11. The fluid machine 101 shown in Figure 11 comprises a motor section 2, a pump section 3, etc. The pump section 3 comprises a compression chamber 73 defined in the circumferential direction by a cylinder 32, a pump rotor 106, and a number of vanes, etc. The pump section 3 forms an area in the fluid machine 101 through which the working fluid flows, excluding the motor section 2.

The fluid machine 101 has a housing integrally formed by a plurality of members. The housing of the fluid machine 101 includes a motor case 124, a suction chamber case 131, a cylinder 32, and a cover 33. The motor case 124 and the suction chamber case 131 are integrally formed via a plate-shaped bearing support member 134. The suction chamber case 131 and the cylinder 32 are integrally formed via a first plate 35. The bearing support member 134, the suction chamber case 131, the first plate 35, the cylinder 32, the second plate 36, and the cover 33 are fixed by bolting or welding, etc. These parts are installed so as to be stacked in the axial direction AD of the shaft 21 to form the housing.

The suction chamber case 131, first plate 35, cylinder 32, second plate 36, and cover 33 are installed so that their respective outer walls are exposed to the atmosphere. These components may be configured so that at least a portion of them is made of a metal with good thermal conductivity. These components only need to be configured so that at least a portion of them is exposed to the atmosphere. With this configuration, heat generated in the sliding parts caused by the rotation of the pump rotor 106 is diffused through the outer wall and released into the atmosphere outside the fluid machine 101.

The suction chamber case 131 forms a suction chamber 71 inside into which the working fluid is drawn. The suction chamber case 131 is provided with an external suction passage 70 that draws the working fluid flowing out from an external device into the suction chamber 71. The external suction passage 70 is a passage that penetrates the suction chamber case 131 in the radial direction, and is an inlet that takes in the working fluid into the housing.

The discharge chamber introduction passage 74 and the compression chamber introduction passage 72 are arranged so that the central axis of the pump rotor 106 is located between them and they face each other in the radial direction. The cylinder 32, the pump rotor 106, the first vane 104 and the second vane 5 constitute a compression mechanism for sucking in, compressing and discharging the working fluid.

As shown in Figure 12, a cylindrical pump rotor 106 is provided inside the cylindrical cylinder 32. A plurality of compression chambers 73 are formed between the outer peripheral surface 6c of the pump rotor 106 and the inner peripheral surface 32a of the cylinder 32. The central axis of the pump rotor 106 is provided at a position offset from the central axis of the cylinder 32. With this configuration, the pump rotor 106 rotates at a position offset to one side inside the cylinder 32. The second vane 5 and the first vane 104 are slidably attached to the pump rotor 106 in a mutually perpendicular orientation.

Each of the first vane 104 and the second vane 5 slides radially while fitted into a slit formed in the pump rotor 106. The radially outer tip 42b of the first vane 104 slides against the inner circumferential surface 32a of the cylinder 32 as the pump rotor 106 rotates. The radially outer tip 52b of the second vane 5 slides against the inner circumferential surface 32a of the cylinder 32 as the pump rotor 106 rotates.

Each of the multiple compression chambers 73 is formed between the second vane 5 and the first vane 104 adjacent to each other in the circumferential direction. The compression chamber 73 is partitioned by the second vane 5, the first vane 104, the inner peripheral surface 32a of the cylinder 32, the outer peripheral surface 6c of the pump rotor 106, the first plate 35, and the second plate 36. As shown in FIG. 12, a compression chamber 73 narrower than the other parts is formed between the narrow outer peripheral surface 6c and the inner peripheral surface 32a. The fluid machine 101 has four compression chambers 73 arranged in the circumferential direction. The fluid machine 101 has two narrow compression chambers 73 and two wide compression chambers 73 located on the opposite side to the two narrow compression chambers 73. The two narrow compression chambers 73 are formed in a portion where the outer peripheral surface 6c is close to the inner peripheral surface 32a. The two wide compression chambers 73 are formed in a portion where the outer peripheral surface 6c is far away from the inner peripheral surface 32a. The four compression chambers 73 move in the circumferential direction as the pump rotor 106 rotates.

The configuration of the pump rotor 106 will be described with reference to Figures 12, 13, 14, and 15. The pump rotor 106 has a supported portion 61 that is supported in contact with a connecting portion 137. The connecting portion 137 is a member that connects the pump rotor 106 and the shaft 21. The supported portion 61 is a cylindrical portion that forms an inner circumferential surface that penetrates in the axial direction and has a predetermined axial length. The connecting portion 137 is not pressed into the inner circumferential surface of the supported portion 61, but is in partial contact with it, and the connecting portion 137 and the supported portion 61 are fitted together.

The pump rotor 106 has a one-side cylindrical portion 62 located closer to the motor section 2 than the supported portion 61, and an other-side cylindrical portion 63 located closer to the discharge chamber 75 than the supported portion 61. The inner circumferential surfaces of the one-side cylindrical portion 62 and the other-side cylindrical portion 63 are formed to have a larger inner diameter than the inner circumferential surface of the supported portion 61. The pump rotor 106 has a through portion that is axially penetrated by the one-side cylindrical portion 62, the supported portion 61, and the other-side cylindrical portion 63.

The pump rotor 106 is provided with a first slit 6sa1, a second slit 6sa2, a third slit 6sb1, and a fourth slit 6sb2. The first slit 6sa1 and the second slit 6sa2 are slits into which the first vane 104 fits. The third slit 6sb1 and the fourth slit 6sb2 are slits into which the second vane 5 fits. The first slit 6sa1 and the second slit 6sa2 are provided in a position rotated 90 degrees from the third slit 6sb1 and the fourth slit 6sb2 in the pump rotor 106. The first slit 6sa1 and the second slit 6sa2 are continuous and form a U-shaped slit that is convex on the discharge chamber 75 side. The third slit 6sb1 and the fourth slit 6sb2 are continuous and form a U-shaped slit that is convex on the motor section 2 side.

The first slit 6sa1 is a slit that passes through the center axis of the pump rotor 106 on the discharge chamber 75 side of the pump rotor 106 and penetrates the entire diameter of the pump rotor 106. The first slit 6sa1 is a one-side slit that extends in the radial direction of the pump rotor 106 through the center axis of the pump rotor 106 on one side of the supported portion 61 in the axial direction. The first slit 6sa1 extends through the center axis of the pump rotor 106 to the outer circumferential surface 6c. The second slit 6sa2 is a slit that is connected to both ends of the first slit 6sa1 and penetrates the pump rotor 106 in the axial direction on the motor portion 2 side of the pump rotor 106. The second slit 6sa2 is a slit that is provided so as not to pass through the center axis of the pump rotor 106. The second slit 6sa2 is an other-side slit that extends in the axial direction from both radial ends of the one-side slit on the other side of the supported portion 61.

The pump rotor 106 has a pair of second slits 6sa2 on the outer peripheral surface 6c side of the pump rotor 106. The first slits 6sa1 and the second slits 6sa2 penetrate from the discharge chamber side surface 6a to the motor side surface 6b of the pump rotor 106 on the outer peripheral surface 6c side of the pump rotor 106. The discharge chamber side surface 6a and the motor side surface 6b face each other and are end surfaces of the pump rotor 106 that are perpendicular to the axial direction.

The third slit 6sb1 is a slit that passes through the center axis of the pump rotor 106 on the motor section 2 side of the pump rotor 106 and penetrates the entire diameter of the pump rotor 106. The third slit 6sb1 is a one-side slit that extends in the radial direction of the pump rotor through the center axis of the pump rotor 106 on one side of the supported portion 61 in the axial direction. The third slit 6sb1 extends through the center axis to the outer circumferential surface 6c in the pump rotor 106. The fourth slit 6sb2 is a slit that is connected to both ends of the third slit 6sb1 and penetrates the pump rotor 106 in the axial direction on the discharge chamber 75 side of the pump rotor 106. The fourth slit 6sb2 is a slit that is provided so as not to pass through the center axis of the pump rotor 106. The fourth slit 6sb2 is an other-side slit that extends in the axial direction from both radial ends of the one-side slit on the other side of the supported portion 61.

The pump rotor 106 has a pair of fourth slits 6sb2 on the outer peripheral surface 6c side of the pump rotor 106. The third slits 6sb1 and the fourth slits 6sb2 penetrate from the surface 6a on the discharge chamber side of the pump rotor 106 to the surface 6b on the motor side on the outer peripheral surface 6c side of the pump rotor 106.

As shown in FIG. 16, the second vane 5 is a U-shaped plate-like member that is convex toward the motor unit 2. The second vane 5 has a radial extension portion 51 that is elongated in the radial direction on the motor unit 2 side, and a pair of axial extension portions 52 that extend in the axial direction from both ends of the radial extension portion 51. The radial extension portion 51 is elongated in the radial direction more than in the axial direction and has a radial length that is longer than the outer diameter dimension of the pump rotor 106. The radial extension portion 51 has an axial length that is smaller than or equal to the axial length of the third slit 6sb1. The second vane 5 is provided so that the motor side end portion 51a, which is the end of the radial extension portion 51 on the motor unit side, is aligned with the surface 6b on the motor unit side. The motor side end portion 51a may be configured to slide against the discharge chamber side surface 35a of the first plate 35 as the pump rotor 106 rotates.

The axial extension portion 52 has a radial length from the radially outer tip portion 52b to the radially inner end portion 52c. The radial length of the axial extension portion 52 is equal to the radial length of the fourth slit 6sb2. The second vane 5 is provided so that the discharge chamber side end portion 52a, which is the end on the discharge chamber side of the axial extension portion 52, is aligned with the discharge chamber side surface 6a. The discharge chamber side end portion 52a may be configured to slide against the motor side surface 36a of the second plate 36 as the pump rotor 106 rotates. The second vane 5 is provided so that the radially outer tip portion 52b, which is the end on the radially outer side of the axial extension portion 52, is aligned with the outer peripheral surface 6c.

17, the first vane 104 is a U-shaped plate-like member that is convex toward the discharge chamber 75 side. The first vane 104 has a radial extension portion 41 that is elongated in the radial direction on the discharge chamber 75 side, and a pair of axial extension portions 42 that extend in the axial direction from both ends of the radial extension portion 41. The radial extension portion 41 is elongated in the radial direction more than in the axial direction, and has a radial length that is longer than the outer diameter dimension of the pump rotor 106. The radial extension portion 41 has an axial length that is smaller than or equal to the axial length of the first slit 6sa1. The first vane 104 is provided so that the discharge chamber side end portion 41a, which is the end on the discharge chamber side of the radial extension portion 41, is along the surface 6a on the discharge chamber side. The discharge chamber side end portion 41a may be configured to slide against the motor side surface 36a of the second plate 36 as the pump rotor 106 rotates.

The axial extension portion 42 has a radial length from the radially outer tip portion 42b to the radially inner end portion 42c. The radial length of the axial extension portion 42 is equal to the radial length of the second slit 6sa2. The first vane 104 is provided so that the motor side end portion 42a, which is the end of the axial extension portion 42 on the motor side, is aligned with the motor side surface 6b. The motor side end portion 42a may be configured to slide against the discharge chamber side surface 35a of the first plate 35 as the pump rotor 106 rotates. The first vane 104 is provided so that the radially outer tip portion 42b, which is the end of the radially outer side of the axial extension portion 42, is aligned with the outer peripheral surface 6c.

The pump rotor 106 is provided with an engagement hole 6d that forms a hole penetrating in the axial direction. As shown in FIG. 18, the engagement hole 6d is in contact with the driving pin 64 that is inserted through it. The driving pin 64 supports the pump rotor 106 at the engagement portion 64b that engages with the engagement hole 6d. The driving pin 64 has a motor side portion 64a, which is the end portion on the motor unit 2 side, fixed to the base portion 373. The base portion 373 is coaxially coupled to the connecting portion 137 and is provided coaxially with the shaft 21. The base portion 373 and the connecting portion 137 rotate together with the shaft 21 as the shaft 21 rotates. The base portion 373 drives the pump rotor 106 via the driving pin 64. With this configuration, the base portion 373, the connecting portion 137, and the pump rotor 106 rotate together with the shaft 21. The shaft 21 is a driving portion that provides a rotational driving force to the pump rotor 106.

The pump rotor 106 has a motor-side non-supported portion 6e that is spaced apart from the driving pin 64 and is not supported on the motor side from the engagement hole portion 6d. The pump rotor 106 has a discharge chamber-side non-supported portion 6f that is spaced apart from the driving pin 64 and is not supported on the discharge chamber side from the engagement hole portion 6d. This configuration contributes to the engagement portion 64b contacting at a position close to the axial center of the pump rotor 106. This makes it possible to suppress the pump rotor 106 from being tilted in the axial direction due to a strong moment acting on the pump rotor 106. Therefore, it is possible to prevent the discharge chamber side surface 6a and the motor side surface 6b from strongly contacting the motor side surface 36a of the second plate 36 and the discharge chamber side surface 35a of the first plate 35.

When the engagement portion 64b of the drive pin 64 and the engagement hole portion 6d are engaged with a gap formed therebetween, the pump rotor 106 may have some play in the rotational direction. For this reason, a gap is set between the radial extension portion 51 and the opposing surface 372a so that the pair of other side support portions 1372 and the radial extension portion 51 do not interfere with each other.

The suction chamber case 131, cylinder 32, first plate 35, second plate 36, and cover 33 can be made of metal, resin, etc. The pump rotor 106 is made of a stainless steel material. The first plate 35 and the second plate 36 have a polytetrafluoroethylene coating on the sliding surface that slides against the pump rotor 106. Alternatively, the pump rotor 106 may be made of carbon, and the first plate 35 and the second plate 36 may be made of a stainless steel material. This contributes to ensuring sliding performance under oil-free conditions where no lubricating oil is supplied from the outside.

The first vane 104 and the second vane 5 are preferably made of carbon. This configuration helps to reduce wear and seizure between the tip of the vane and the inner surface of the cylinder 32. This configuration is useful in a fluid machine 101 that is used under oil-free conditions.

The motor section 2 is integrally provided in the suction chamber case 131 on the side opposite the cylinder 32. The suction chamber case 131 defines a suction chamber 71 inside. The motor case 124 is fixed integrally to the bearing support member 134 by a configuration in which the end of the cylindrical body is connected to the bearing support member 134. The motor case 124 also serves as a yoke in the motor section 2. The motor case 124 is part of the housing in the fluid machine 101. The motor section 2 has a stator 23, a motor rotor 22, a shaft 21, etc., which are provided inside the motor case 124.

The stator 23 covers the outer periphery of the motor rotor 22. Various motors, such as a brushed motor or a brushless motor, can be used as the motor section 2. The shaft 21 is rotatably supported by a first bearing section 211 and a second bearing section 212 provided inside the motor case 124. The second bearing section 212 is supported by the support section 34a of the bearing support member 134. The second bearing section 212 is located inside the suction chamber case 131.

The stator 23, motor rotor 22, etc. are located in a motor chamber 241 formed inside the motor case 124. The motor chamber 241 is formed by an internal space surrounded by the motor case 124, the bearing support member 134, and the second bearing portion 212. The motor chamber 241 is a space portion adjacent to the suction chamber 71 via the bearing support member 134. The support portion 34a of the bearing support member 134 contacts the outer periphery of the second bearing portion 212 to support the second bearing portion 212. The second bearing portion 212 has a pump rotor side end face 212a located on the pump rotor 106 side and a motor side end face 212b located on the motor rotor 22 side. The motor side end face 212b is not exposed to the suction chamber 71 and does not come into contact with the working fluid.

The connecting portion 137 and the pump rotor 106 are separate parts. The connecting portion 137, the pump rotor 106 and the shaft 21 are arranged coaxially and are driven to rotate as a unit. The other end shaft portion 21b of the shaft 21 is connected to the connecting portion 137. The connecting portion 137 has a one-side connecting portion 371 that connects to the shaft 21 and a pair of other-side support portions 1372 that support the pump rotor 106. The one-side connecting portion 371 is located on the motor portion 2 side of the connecting portion 137. The pair of other-side support portions 1372 are located on the discharge chamber 75 side of the connecting portion 137.

11 and 12, the other-side support portion 1372 has an opposing surface 372a along the axial direction and the radial direction. The pair of other-side support portions 1372 face each other with a predetermined interval in the radial direction RD. The predetermined interval corresponds to the distance between the opposing surfaces 372a and 372a in the pair of other-side support portions 1372. The pair of other-side support portions 1372 constitute a support portion that is open on the discharge chamber 75 side. The pair of other-side support portions 1372 constitute a support portion that is open on the radially outer side. Between the pair of other-side support portions 1372, a radial extension portion 51 of the second vane 5 extending in the radial direction is interposed. The radial extension portion 51 and the opposing surface 372a are spaced apart. The radial extension portion 51 can slide between the pair of other-side support portions 1372 during rotation of the pump rotor 106.

The pump rotor 106 contacts the outer circumferential surface of the other-side support part 1372 at the supported part 61, and does not contact the connecting part 137 at any part other than the supported part 61. The other-side support part 1372 supports the supported part 61 so that the pump rotor 106 and the connecting part 137 can move axially relative to each other. The other-side support part 1372 also supports the supported part 61 so that the connecting part 137 and the pump rotor 106 can tilt relative to the axis of the shaft 21. The pair of other-side support parts 1372 has a fixed end at the end on the motor part 2 side and a free end at the end on the discharge chamber 75 side. Because of this cantilever structure, the other-side support part 1372 can bend so as to move radially. This bending action contributes to supporting the supported part 61 so that it can tilt relative to the shaft 21.

The other side support part 1372 and the supported part 61 are connected together so as to be relatively movable in the axial direction and/or tiltable. The other side support part 1372 and the supported part 61 may be configured to be fitted together so as to be relatively movable in the axial direction and/or tiltable. The other side support part 1372 and the supported part 61 may be configured to have a connection structure in which a part of both of them contacts and the remaining part is separated so as to be relatively movable in the axial direction and/or tiltable. It is preferable that the other side support part 1372 and the supported part 61 are connected together so as to be relatively movable in the axial direction and tiltable. The term "relatively movable in the axial direction" refers to a state in which one of the shaft 21 and the pump rotor 106 can rotate while moving in the axial direction relative to the other. The term "relatively tiltable" refers to a state in which one of the shaft 21 and the pump rotor 106 can rotate while tilting or in a tilted state relative to the other.

The central axis of the shaft 21 is the rotation axis of the pump rotor 106. The shaft 21 is a drive shaft that rotates the pump rotor 106 via the drive pin 64.

The tip surface of the tip portion 42b has a curved surface formed with a predetermined radius. When the motor portion 2 is energized, the shaft 21 rotates around the rotation axis. At that time, the torque output by the motor portion 2 is transmitted to the pump rotor 106 via the base portion 373 and the drive pin 64. The pump rotor 106 rotates within the cylinder 32 while forming an arc-shaped seal portion on the outer circumferential surface 6c that is closest to the inner circumferential surface 32a and a separation portion that is significantly separated from the inner circumferential surface 32a. The separation portion is a portion of the outer circumferential surface 6c that is located on the opposite side to the arc-shaped seal portion. The length of the portion that protrudes radially outward from the outer circumferential surface 6c is maximum at the separation portion and minimum at the arc-shaped seal portion.

The vane rotates together with the pump rotor 106 while sliding radially against and away from the inner circumferential surface 32a of the cylinder 32 as the pump rotor 106 rotates. A minute gap is provided between the inner circumferential surface 32a of the cylinder 32 and the tip 42b so that the vane does not become tense during one rotation. This minute gap is preferably set to about 50 μm to 200 μm to suppress leakage of the working fluid and noise.

The gap between the tip 42b and the inner circumferential surface 32a in the arc-shaped seal portion is almost constant, and a stable seal length can be ensured in the arc-shaped seal portion. The rotation angle of the arc-shaped seal portion is preferably set in the range of 20 degrees to 60 degrees from the viewpoint of suppressing wear of the vane, etc. The rotation position at which the gap between the tip 42b and the inner circumferential surface 32a is smallest changes during one rotation of the vane. One tip 42b of the vane may contact the inner circumferential surface 32a at a rotation position other than the arc-shaped seal portion and the separation portion. The vane and the inner circumferential surface 32a of the cylinder 32 are formed so that the gap between the other tip 42b and the inner circumferential surface 32a is almost constant during one rotation of the vane.

The fluid machine 101 forms a narrow compression chamber 73 on the arc-shaped seal side and a wide compression chamber 73 on the separation side. The narrow compression chamber 73 moves in the rotational direction while the vane rotates, and expands as it approaches the separation part, changing into a wide compression chamber 73. The wide compression chamber 73 moves in the rotational direction while the vane rotates, and shrinks as it approaches the arc-shaped seal part, changing into a narrow compression chamber 73. In this way, each compression chamber 73 changes so that its volume gradually decreases as it approaches the discharge chamber introduction passage 74 during one rotation of the vane. The fluid machine 101 compresses the air supplied to the compression chamber 73 through the compression chamber introduction passage 72, and discharges this air from the discharge chamber introduction passage 74 to the discharge chamber 75.

In the fluid machine 101, the air, which is the working fluid, flows down through the external suction passage 70, the suction chamber 71, the compression chamber introduction passage 72, and the compression chamber 73. The air then flows down from the compression chamber 73 through the discharge chamber introduction passage 74 and the discharge chamber 75, before flowing out through the discharge port 76 to the outside. In this way, as the air flows through this fluid path, it cools each part, and contributes to effectively releasing heat, especially from the sliding parts.

Each of the first vane 104 and the second vane 5 is a through vane that extends through the pump rotor 106 through the central axis of the pump rotor 106. The through vane has a longer support length at the portion supported by the pump rotor 106 compared to a vane that does not pass through the central axis of the pump rotor 106. This makes it possible to reduce the load that the portion of the pump rotor 106 in which the slits are formed receives from the vane. Due to this effect, the through vane type fluid machine 101 can form the pump rotor 106 from a resin. It is preferable to use polyphenylene sulfide or polyether ether ketone as the resin to provide heat resistance. The pump rotor 106 may be formed from a material containing polytetrafluoroethylene or carbon that has self-lubricating properties.

The effects of the fluid machine 101 of the second embodiment will be described. The through vane type fluid machine 101 includes a pump rotor 106, a shaft 21 that provides a rotational driving force to the pump rotor 106, and a vane that slides radially through the central axis of the pump rotor 106. The fluid machine 101 includes a compression chamber 73 that compresses the working fluid as the pump rotor rotates, and a support that connects the supported part 61 of the pump rotor 106 and the shaft 21. The compression chamber 73 is defined in the circumferential direction by the vane between the inner surface of the housing and the outer circumferential surface 6c of the pump rotor 106. The support part and the supported part 61 are connected together so as to be able to move axially and/or tilt relatively to each other.

According to this configuration, the unique connection structure between the support part and the supported part 61 allows the pump rotor 106 to move axially or tilt with respect to the axial direction of the support part. In other words, the restriction of the pump rotor 106 with respect to the attitude of the shaft 21 and the support part is reduced, and the degree of freedom in the attitude of the pump rotor 106 can be increased. This displaceable characteristic of the pump rotor 106 prevents the pump rotor 106 from coming into strong contact with surrounding members such as the first plate 35 and the second plate 36 and receiving a local load. Therefore, it is possible to provide a through vane type fluid machine that can suppress mechanical losses.

The support portion has a gap extending radially through the central axis of the pump rotor 106, inside the portion in contact with the supported portion 61. This gap is formed between the opposing surfaces 372a and 372a of the pair of other support portions 1372. The radial extension portion 51 of the slidable second vane 5 is located in this gap. This makes it possible to suppress mechanical loss and provide a fluid machine that has the function of allowing the vane to slide inside the support portion.

The pump rotor 106 has a one-side slit on one side of the supported portion 61 in the axial direction, and a other-side slit on the other side of the supported portion 61. The one-side slit passes through the central axis of the pump rotor 106 and extends in the radial direction of the pump rotor 106. The other-side slits extend in the axial direction from both radial ends of the one-side slit.

This configuration makes it possible to provide a pump rotor 106 that has a supported portion at the axial center. Because the pump rotor 106 can be displaced relative to the support portion starting from a position close to the axial center, the pump rotor 106 can have a symmetrical range of movement starting from the axial center. This makes it possible to provide a through-vane type fluid machine that can equally suppress mechanical loss in the surrounding components on either side of the pump rotor 106 in the axial direction.

The shaft 21 is provided on only one side of the pump rotor 106 in the axial direction and is supported by a bearing portion. The shaft 21 is not supported by a bearing portion on the other side of the pump rotor 106 in the axial direction. In this manner, the shaft 21 is provided rotatably only on one side of the pump rotor 106 and is not provided on the other side. Therefore, the tilt of the shaft 21 can be suppressed, and a fluid machine 101 can be provided that can reduce the range of tilt of the pump rotor 106.

The bearings provided on both sides of the motor rotor 22 in the motor section 2 are provided on one side of the pump rotor 106. This contributes to suppressing the tilt of the shaft 21, and makes it possible to provide a fluid machine 101 that can reduce the range of tilt of the pump rotor 106.

The fluid machine 101 is a device used under oil-free conditions where there is no lubricating oil supplied from the outside. This makes it possible to provide a fluid machine 101 that can suppress mechanical loss between the pump rotor 106 and surrounding components due to the displaceable characteristics of the pump rotor 106, and also contributes to preventing seizure when no oil is supplied.

Third Embodiment
The third embodiment will be described with reference to Figures 19 and 20. A fluid machine 201 of the third embodiment is different from the first embodiment in that it is a rotary vane type fluid machine. The configurations, actions, and effects of the third embodiment that are not specifically described are the same as those of the above-mentioned embodiments, and only the differences will be described below.

The fluid machine 201 is a rotary vane type fluid machine having a cylinder 132 and a pump rotor 206. The cylinder 132 is part of the housing of the fluid machine 201.

A compression chamber 73 is formed between the outer peripheral surface 6c of the pump rotor 206 and the inner peripheral surface 32a of the cylinder 32. A vane 204 is slidably mounted in the cylinder 132.

The vane 204 slides radially while fitted into a slit 132s formed in the cylinder 132. The tip 204a located on the rotor side of the vane 204 is in contact with the outer circumferential surface 6c of the pump rotor 206. The other tip 204b of the vane 204 is in contact with an elastic member 39 such as a spring. As a result, the vane 204 is biased against the pump rotor 206 so that the tip 204a is pressed against the outer circumferential surface 6c of the pump rotor 206. The tip 204a located on the rotor side of the vane 204 slides against the outer circumferential surface 6c of the pump rotor 206 as the pump rotor 206 rotates.

The fluid machine 201 has two compression chambers 73 divided in the circumferential direction by a vane 204. Each compression chamber 73 is defined by the vane 204, the inner peripheral surface 32a of the cylinder 32, the outer peripheral surface 6c of the pump rotor 206, the first plate 35, and the second plate 36.

An eccentric portion 38 is fixed to the other end shaft portion 21b of the shaft 21. The eccentric portion 38 is installed so that its central axis is offset from the rotation axis of the shaft 21. The eccentric portion 38 is fixed to the pump rotor 206 so that its central axis coincides with the central axis of the pump rotor 206. Therefore, the central axis of the pump rotor 206 is set to a position offset from the central axis of the shaft 21. When the motor portion 2 is energized and the shaft 21 rotates around its rotation axis, the torque output by the motor portion 2 is transmitted to the pump rotor 206 via the eccentric portion 38. The pump rotor 206 revolves around the rotation axis of the shaft 21. The revolution radius is equal to the distance between the central axis of the eccentric portion 38 and the rotation axis of the shaft 21.

Fourth Embodiment
A fourth embodiment disclosing an example of a fluid machine will be described with reference to FIGS. 21 to 23. The fluid machine is a through vane type fluid machine. The vanes are arranged through the central axis of the pump rotor 106. The vanes extend through the pump rotor 106. The vanes are supported by the pump rotor 106 so as to slide in the radial direction of the pump rotor 106. In this embodiment, the same elements as those in the embodiment shown in FIG. 11 and corresponding elements are given the same reference numerals. For the elements of this embodiment, the description of the preceding embodiment can be referred to. In the embodiment of FIG. 11, the external suction passage 70 has a first passage portion 70a and a second passage portion 70b. In the embodiment of FIG. 21, the external suction passage 70 is cylindrical without a step portion. The external suction passage 70 in the embodiment of FIG. 21 may include a first passage portion 70a and a second passage portion 70b. In the embodiment of FIG. 11, an introduction member 8 is provided. The embodiment of FIG. 21 does not include an introduction member 8. The embodiment of FIG. 21 may include an introduction member 8 .

The suction chamber case 131 forms a suction chamber 71 on the inside into which the working fluid is drawn. The suction chamber case 131 is provided with an external suction port 70 that draws the working fluid flowing out from an external device into the suction chamber 71. The external suction port 70 is a passage that penetrates the suction chamber case 131 in the radial direction, and is an inlet that takes in the working fluid into the inside of the fluid machine 101. The external suction port 70 has a cross-sectional area perpendicular to the passage axial direction set to S0. The suction chamber 71 has a cross-sectional area S1 immediately after the working fluid flows into the external suction port 70. The cross-sectional area S1 is the cross-sectional area of a plane perpendicular to the radial direction RD. This cross section is the cross section at the position where the length of the axial direction AD is the longest in the suction chamber 71. The cross section with S1 and the cross section with area S0 are parallel to each other. It is preferable that S1 is set to a value 10 times or more greater than S0.

The suction chamber 71 has a cross-sectional area perpendicular to the axial direction set to S11. The cross-sectional area S11 is the cross-sectional area at the largest position in the suction chamber 71. The compression chamber introduction passage 72 is elongated in the circumferential direction and forms an opening that is shaped to follow the inner circumferential surface 32a of the cylinder 32. The compression chamber introduction passage 72 has a cross-sectional area perpendicular to the passage axial direction set to S2. The cross section with area S11 and the cross section with area S2 are parallel to each other. It is preferable that S11 is set to a value 10 times or more larger than S2. Such a relationship between the magnitudes of S0, S1, S11, and S2 contributes to reducing the backflow of radiated sound due to suction pulsation.

The compression chamber introduction passage 72 is located in an area opposite the suction port area on the side of the shaft 21 where the external suction port 70 is located. In other words, when viewed in the axial direction of the shaft 21, the compression chamber introduction passage 72 and the external suction port 70 are located in opposing areas with the shaft 21 between them. The working fluid that flows into the suction chamber 71 from the external suction port 70 flows around the shaft 21, passes the shaft 21, changes flow in the axial direction, and reaches the compression chamber introduction passage 72.

The discharge chamber introduction passage 74 is elongated in the circumferential direction and forms an opening that is shaped to fit along the inner surface 32a of the cylinder 32.

The cylinder 32, the pump rotor 106, the first vane 104 and the second vane 5 constitute a compression mechanism for drawing in, compressing and discharging the working fluid.

As shown in Figure 22, a cylindrical pump rotor 106 is provided inside the cylindrical cylinder 32. The second vane 5 and the first vane 104 are slidably mounted on the pump rotor 106 in a mutually perpendicular orientation.

Each of the first vane 104 and the second vane 5 slides radially while fitted into a slit formed in the pump rotor 106. The radially outer tip 42b of the first vane 104 slides against the inner circumferential surface 32a of the cylinder 32 as the pump rotor 106 rotates. The radially outer tip 52b of the second vane 5 slides against the inner circumferential surface 32a of the cylinder 32 as the pump rotor 106 rotates.

Each of the multiple compression chambers 73 is formed between the second vane 5 and the first vane 104 that are adjacent in the circumferential direction. The compression chamber 73 is partitioned by the second vane 5, the first vane 104, the inner peripheral surface 32a of the cylinder 32, the outer peripheral surface 6c of the pump rotor 106, the first plate 35, and the second plate 36. The fluid machine 101 has four compression chambers 73 arranged in the circumferential direction. The fluid machine 1 has two narrow compression chambers 73 and two wide compression chambers 73 located on the opposite side to the two narrow compression chambers 73. The four compression chambers 73 move in the circumferential direction as the pump rotor 106 rotates.

The pump rotor side end face 212a and the motor side end face 212b are located opposite each other in the axial direction of the shaft 21, and each form an annular surface around the axis of the shaft 21. The pump rotor end face 212a is exposed to the suction chamber 71 and can come into contact with the working fluid flowing through the suction chamber 71. The motor side end face 212b is not exposed to the suction chamber 71 and does not come into contact with the working fluid.

22 shows the positional relationship between the inner circumferential surface 32a of the cylinder 32 and the radially outer tip 42b of the first vane 4 at the rotational position of the pump rotor 6. The following description applies to each of the first vane 4 and the second vane 5. The tip surface of the tip 42b has a curved surface formed with a predetermined radius. When the motor unit 2 is energized, the shaft 21 rotates around the rotation axis. At that time, the torque output by the motor unit 2 is transmitted to the pump rotor 6 via the pedestal portion 373 and the driving pin 64. The pump rotor 6 rotates in the cylinder 32 with a circular arc seal portion that is closest to the inner circumferential surface 32a and a separation portion that is greatly separated from the inner circumferential surface 32a formed on the outer circumferential surface 6c. As shown in FIG. 22, the circular arc seal portion corresponds to the range of the rotation angle AG. The separation portion is a portion located on the opposite side of the outer circumferential surface 6c to the circular arc seal portion. The length of the portion protruding radially outward beyond the outer circumferential surface 6c is maximum at the separation portion and minimum at the arc-shaped seal portion.

The vane rotates together with the pump rotor 6 while sliding radially against and away from the inner circumferential surface 32a of the cylinder 32 during the rotation of the pump rotor 6. The tip 42b of the first vane 4 is displaced, for example, as shown by the two-dot chain line in FIG. 22 during one rotation of the vane. A minute gap is provided between the inner circumferential surface 32a of the cylinder 32 and the tip 42b so that the vane does not become taut during one rotation of the vane. This minute gap is preferably set to about 50 μm to 200 μm in order to suppress leakage of the working fluid and noise. The gap GP1 between the tip 42b and the inner circumferential surface 32a in the arc-shaped seal portion is almost constant, and a stable seal length can be secured in the arc-shaped seal portion. The rotation angle AG of the arc-shaped seal portion is preferably set in the range of 20 degrees to 60 degrees from the viewpoint of suppressing wear of the vane, etc. During one rotation of the vane, the rotation position at which the gap between the tip 42b and the inner circumferential surface 32a is smallest is displaced. In the vane, one tip portion 42b may come into contact with the inner peripheral surface 32a at a rotational position excluding the arc-shaped seal portion and the spaced portion. At this time, the other tip portion 42b and the inner peripheral surface 32a are set to a gap GP2. The vane and the inner peripheral surface 32a of the cylinder 32 are formed so that the gap GP2 is approximately constant during one rotation of the vane.

As shown in Figure 23, the tip surface of the tip portion 42b is curved so that the sliding length SL over which the tip portion 42b contacts and slides against the inner circumferential surface 32a is smaller than the thickness TH of the vane. This configuration ensures a stable sliding state of the vane.

Fifth Embodiment
The fifth embodiment will be described with reference to Figures 24 to 28. A fluid machine 501 of the fifth embodiment differs from the embodiment of Figures 11 and 21 in that it has two compression chambers 73 partitioned by vanes. Configurations, actions, and effects of the fifth embodiment that are not specifically described are similar to those of the above-mentioned embodiments, and only the differences will be described below.

The fluid machine 501 in Fig. 24 has only one through vane. Due to this configuration, the fluid machine 501 in Fig. 24 differs from the fluid machine 101 in Fig. 21 in the connection part 537 and the pump rotor 506.

The configuration of the pump rotor 506 will be described with reference to Figures 25, 26, 27, and 28. The pump rotor 506 has a supported portion 61 that is supported in contact with a connecting portion 537. The connecting portion 537 is a member that connects the pump rotor 506 and the shaft 21. The connecting portion 537 is not press-fitted into the inner circumferential surface of the supported portion 61, but is in partial contact therewith, and the connecting portion 537 and the supported portion 61 are fitted together.

The pump rotor 506 has a one-side cylindrical portion 62 located closer to the motor section 2 than the supported portion 61, and a second-side cylindrical portion 63 located closer to the discharge chamber 75 than the supported portion 61. The pump rotor 506 has a through portion that is axially penetrated by the one-side cylindrical portion 62, the supported portion 61, and the second-side cylindrical portion 63.

The pump rotor 506 is provided with a first slit 6sa1 and a second slit 6sa2 similar to those of the pump rotor 106. The first slit 6sa1 in the pump rotor 506 is a one-side slit extending radially through the central axis of the pump rotor 506 on one side of the supported portion 61 in the axial direction. The second slit 6sa2 in the pump rotor 506 is an other-side slit extending axially from both radial ends of the one-side slit on the other side of the supported portion 61.

The pump rotor 506 does not have the third slit 6sb1 and the fourth slit 6sb2 that the pump rotor 106 has. The fluid machine 501 has a first vane 4 that fits into the first slit 6sa1 and the second slit 6sa2. The pump rotor 506 has a U-shaped slit that is convex toward the discharge chamber 75, with the first slit 6sa1 and the second slit 6sa2 continuing together.

The connecting portion 537 and the pump rotor 506 are separate parts. The connecting portion 537, the pump rotor 506 and the shaft 21 are arranged coaxially and are rotated and driven together. The other end shaft portion 21b of the shaft 21 is connected to the connecting portion 537. The connecting portion 537 has a one-side connecting portion 371 that connects to the shaft 21 and an other-side support portion 1372 that supports the pump rotor 506. The one-side connecting portion 371 is located on the motor portion 2 side of the connecting portion 537. The other-side support portion 1372 is located on the discharge chamber 75 side of the connecting portion 537.

As shown in Figures 24 and 25, the other-side support part 1372 is a columnar part formed coaxially with the shaft 21. The pump rotor 506 contacts the outer peripheral surface of the other-side support part 1372 at the supported part 61, and does not contact the connecting part 537 at any part other than the supported part 61. The other-side support part 1372 supports the supported part 61 so that the pump rotor 506 and the connecting part 537 can move axially relative to each other. The other-side support part 1372 also supports the supported part 61 so that the connecting part 537 and the pump rotor 506 can tilt relative to the axis of the shaft 21.

Each of the two compression chambers 73 is defined by the first vane 4, the inner peripheral surface 32a of the cylinder 32, the outer peripheral surface 6c of the pump rotor 506, the first plate 35, and the second plate 36. The fluid machine 501 has two compression chambers 73 arranged circumferentially with the first vane 4 as a boundary. The two compression chambers 73 move circumferentially as the pump rotor 506 rotates.

During one rotation of the vane, the fluid machine 501 forms a narrow compression chamber 73 at a position including the arc-shaped seal portion, and a wide compression chamber 73 at a position including the separation portion. The narrow compression chamber 73 moves in the rotation direction with the rotation of the first vane 4, and changes to a wide compression chamber 73 when it reaches a rotation position including the separation portion. The wider compression chamber 73 moves in the rotation direction with the rotation of the first vane 4, and changes to a narrow compression chamber 73 when it reaches a rotation position including the arc-shaped seal portion. In this way, each compression chamber 73 changes so that its volume gradually decreases as the tip portion 42b approaches the discharge chamber introduction passage 74 during one rotation of the first vane 4. Therefore, the air supplied to the compression chamber 73 through the compression chamber introduction passage 72 is compressed, and this air is discharged from the discharge chamber introduction passage 74 to the discharge chamber 75.

The pump rotor 506 of the fifth embodiment is provided with a one-side slit on one side of the supported portion 61 in the axial direction, and a other-side slit on the other side of the supported portion 61. The one-side slit passes through the central axis of the pump rotor 506 and extends in the radial direction of the pump rotor 506. The other-side slit of the pump rotor 506 extends in the axial direction from both radial ends of the one-side slit.

Sixth Embodiment
This embodiment is a modification based on the preceding embodiment or the modification, and includes a second seal portion 618.

As shown in FIG. 29, the second seal portion 618 contacts the shaft 21 and the first plate 35 to fluidically seal the gap therebetween. The second seal portion 618 blocks fluid communication between the space on the pump side and the space on the suction chamber 71 side. The second seal portion 618 contacts the shaft 21. The second seal portion 18 contacts the outer peripheral surface of the shaft 21. The contact portion of the shaft 21 with the second seal portion 618 is included in a drive shaft portion for driving the pump rotor 6. The shaft 21 is disposed to penetrate the first plate 35. In other words, the drive shaft portion is disposed to penetrate the first plate 35.

The second seal portion 618 is held between the first plate 35, which is a member through which the drive shaft portion passes, and the compression chamber side end face of the cylindrical wall portion 341. The second seal portion 618 is sandwiched between the first plate 35 and the cylindrical wall portion 341. An elastic member such as an O-ring is arranged between the compression chamber side end face of the cylindrical wall portion 341 and the second seal portion 618. The second seal portion 618 is pressed against the first plate 35 by the O-ring. The second seal portion 618 provides a lip seal that allows the shaft 21 to rotate.

In this embodiment, the second seal portion 618 is held to allow rotation of the shaft 21. The second seal portion 618 suppresses the flow and leakage of fluid through the gap between the first plate 35 and the shaft 21. The second seal portion 618 suppresses leakage of fluid from the compression chamber 73 side to the suction chamber 71 side.

The central axis of the shaft 21 is the rotation axis of the pump rotor 6. The shaft 21 is provided with a drive pin 664. The shaft 21 is a part that rotates the pump rotor 6 via the drive pin 664. The shaft 21, together with the connecting part 37, constitutes a drive shaft part that drives the pump rotor 6.

The drive pin 664 is connected to the shaft 21 so as to rotate together with the shaft 21. For example, the drive pin 664 is connected by fitting an annular base to the shaft 21. The shaft 21 may be press-fitted into the annular base. The shaft 21 and the drive pin 664 provide a drive shaft for rotating the pump rotor 6. The shaft 21 and the pump rotor 6 include a support portion 372 that supports the pump rotor 6. The drive pin 664 connects the shaft 21 and the pump rotor 6 in the rotational direction radially outward of the support portion 372. The connection between the drive pin 664 and the pump rotor 6 may be provided by a slightly looser fit in the axial and radial directions than the fit at the support portion 372.

The suction chamber case 31 as a housing has a communication passage 340 that communicates the suction chamber 71 and the pump rotor side end face 212a. The communication passage 340 may include a groove-shaped passage in the compression chamber side end face of the cylindrical wall portion 341. The communication passage 340 may include a passage that axially penetrates the wall that provides the compression chamber side end face of the cylindrical wall portion 341. The communication passage 340 is formed between the second seal portion 618 and the cylindrical wall portion 341. As a result, the pump rotor side end face 212a of the second bearing portion 212 provides a portion exposed to the suction chamber 71.

The suction chamber case 31 as a housing has a communication passage 631. The communication passage 631 fluidly connects the suction chamber 71 and the motor chamber 241 directly or indirectly. This embodiment has both the communication passage 340 that directly or indirectly exposes both the pump rotor side end face 212a and the motor side end face 212b of the second bearing portion 212 to the suction chamber 71, and the communication passage 631. The communication passage 631 is formed in a partition wall of the suction chamber case 31 that separates the suction chamber 71 and the motor chamber 241. The communication passage 631 is provided by a hole opened in the partition wall.

The filter 15 is arranged to filter the fluid between the external suction passage 70 and the communication passage 340. The filter 15 is arranged to filter the fluid between the external suction passage 70 and the communication passage 631. In this way, the filter 15 prevents foreign matter from entering from the outside into both the pump rotor side end face 212a and the motor side end face 212b of the second bearing portion 212.

Even if the suction chamber 71 becomes negative pressure due to suction loss, the communication passage 340 and the communication passage 631 suppress the pressure difference between the pump rotor side end face 212a and the motor side end face 212b of the second bearing portion 212. As a result, the outflow of grease from the second bearing portion 212 can be suppressed.

Seventh Embodiment
This embodiment is a modification based on the preceding embodiment or modification. In this embodiment, the filter 15 is arranged to divide the suction chamber 71 into two chambers. The two chambers are positioned so as to be stacked in the axial direction.

In Figure 30, filter 15 is disposed in suction chamber case 31. Filter 15 may have a shape corresponding to the shape of the opening of suction chamber case 31. Suction chamber case 31 has a step for disposing filter 15. Filter 15 is fixed to suction chamber case 31. Filter 15 is fixed to suction chamber case 31 by adhesive or mechanical fastening members.

In the manufacturing method of the fluid machine, the filter 15 is placed in the suction chamber case 31 from the opening of the suction chamber case 31 so that it is placed according to gravity in the suction chamber case 31. The filter 15 is fixed after being placed inside the suction chamber case 31. In this embodiment, the assembly process of the filter 15 in the manufacturing method of the fluid machine can be simplified.

In this embodiment, the filter 15 is also arranged to filter the fluid between the external suction passage 70 and the compression chamber introduction passage 72. As a result, the filter 15 prevents foreign matter from entering the pump from the outside. Furthermore, the filter 15 is arranged to filter the fluid between the external suction passage 70 and the pump rotor side end surface 212a of the second bearing portion 212. As a result, the filter 15 prevents foreign matter from entering the pump rotor side end surface 212a of the second bearing portion 212 from the outside. In this embodiment, the same effects as those of the preceding embodiment are achieved.

Eighth Embodiment
This embodiment is a modification based on the preceding embodiment or a modification thereof, and shows an example of a structure for fixing the filter 15.

31, the fluid machine 1 of this embodiment includes a spacer member 831 for fixing the filter 15. The spacer member 831 is disposed within the suction chamber case 31 to limit movement of the filter 15. The filter 15 is held between the spacer member 831 and the suction chamber case 31. The filter 15 can be held between a member that defines the suction chamber 71 and the spacer member 831. For example, the filter 15 may be held between the spacer member 831 and the first plate 35.

The spacer member 831 allows fluid to flow in the axial direction. Furthermore, the spacer member 831 allows the fluid that has passed through the filter 15 to reach the pump rotor side end surface 212a of the second bearing portion 212. The spacer member 831 can be provided by a member that is permeable to fluid in the radial direction, or a member that has a fluid passage in the radial direction. In this embodiment, too, the effects provided by the elements common to the preceding embodiment are achieved.

<Other embodiments>
The disclosure of this specification is not limited to the exemplified embodiments. The disclosure includes the exemplified embodiments and modifications made by those skilled in the art based thereon. For example, the disclosure is not limited to the combination of parts and elements shown in the embodiments, and can be implemented in various modifications. The disclosure can be implemented by various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure includes those in which parts and elements of the embodiments are omitted. The disclosure includes the replacement or combination of parts and elements between one embodiment and another embodiment. The disclosed technical scope is not limited to the description of the embodiments. The disclosed technical scope is indicated by the description of the claims, and should be interpreted as including all modifications within the meaning and scope equivalent to the description of the claims.

Fluid machines capable of achieving the objectives disclosed in this specification include configurations that combine at least two or more of the first to fifth variants of fluid machine 1.

In the fluid machinery disclosed in this specification, the support part and the supported part, which are separate parts, are integrally connected, but the support part and the shaft may be separate parts or may be one part. The connecting part having the support part in the above embodiment is a separate part from the shaft, but the connecting part and the shaft may be configured as one part.

In the above-described embodiment, the supported portion 61 of the pump rotor is provided in the axial middle of the pump rotor, but is not limited to this configuration. The supported portion 61 may be provided on the axial side of the motor section 2 of the pump rotor. The supported portion 61 may be provided on the axial side of the discharge chamber 75 of the pump rotor.

Claims (19)

A housing (32, 24, 31; 124; 132);
A motor unit (2);
a pump rotor (6; 106; 206; 506) that is driven by a driving force provided by the motor unit and rotates inside the housing;
a suction chamber (71) provided inside the housing, through which working fluid from the outside flows into the inside of the housing via an external suction passage (70);
a compression chamber (73) for compressing and discharging the working fluid supplied through the suction chamber as the pump rotor rotates;
A motor chamber (241) in which the motor unit is housed;
a bearing portion (212) that rotatably supports a shaft (21) that transmits the driving force of the motor portion to the pump rotor;
Equipped with
The bearing portion has a portion exposed to the suction chamber ,
A bearing support portion (34) that supports the bearing portion;
a cylindrical wall portion (341) extending from the bearing support portion toward the compression chamber side and covering the bearing portion radially outward from the bearing portion;
a communication passage (340) that allows a working fluid to travel between an area in contact with the bearing portion and an area radially outside the cylindrical wall portion;
Equipped with
a drive shaft seal portion (618) that contacts and seals a drive shaft portion (21, 37, 373) that drives the pump rotor and a member (35) through which the drive shaft portion penetrates;
The drive shaft seal portion is held between a member through which the drive shaft passes and a compression chamber side end face of the cylindrical wall portion . a vane (4,5;4;104) extending through the pump rotor and sliding radially of the pump rotor;
A support portion (372; 1372) that connects the supported portion (61) of the pump rotor and the shaft;
Equipped with
The compression chamber is defined in a circumferential direction by the vane between an inner peripheral surface (32a) of the housing and an outer peripheral surface (6c) of the pump rotor,
The fluid machine according to claim 1 , wherein the supporting portion and the supported portion are integrally connected to each other so as to be axially movable and/or tiltable relative to each other. The fluid machine according to claim 2, wherein the support portion is provided with a gap portion, inside the portion in contact with the supported portion, through which the vane can slide and which extends radially of the pump rotor through a central axis of the pump rotor. A housing (32, 24, 31; 124; 132);
A motor unit (2);
a pump rotor (6; 106; 206; 506) that is driven by a driving force provided by the motor unit and rotates inside the housing;
a suction chamber (71) provided inside the housing, through which working fluid from the outside flows into the inside of the housing via an external suction passage (70);
a compression chamber (73) for compressing and discharging the working fluid supplied through the suction chamber as the pump rotor rotates;
A motor chamber (241) in which the motor unit is housed;
a bearing portion (212) that rotatably supports a shaft (21) that transmits the driving force of the motor portion to the pump rotor;
Equipped with
The bearing portion has a portion exposed to the suction chamber ,
a vane (4,5;4;104) extending through the pump rotor and sliding radially of the pump rotor;
A support portion (372; 1372) that connects the supported portion (61) of the pump rotor and the shaft;
Equipped with
The compression chamber is defined in a circumferential direction by the vane between an inner peripheral surface (32a) of the housing and an outer peripheral surface (6c) of the pump rotor,
The supporting portion and the supported portion are integrally connected to each other so as to be relatively movable in the axial direction and/or tiltable,
A fluid machine in which a gap is provided in the support portion, inside the portion in contact with the supported portion, through the central axis of the pump rotor and extending radially of the pump rotor, allowing the vane to slide . A bearing support portion (34) that supports the bearing portion;
a cylindrical wall portion (341) extending from the bearing support portion toward the compression chamber side and covering the bearing portion radially outward from the bearing portion;
a communication passage (340) that allows a working fluid to travel between an area in contact with the bearing portion and an area radially outside the cylindrical wall portion;
The fluid machinery according to claim 4 . The fluid machine according to claim 4 or 5, further comprising a drive shaft seal portion (18, 618) that contacts and seals a drive shaft portion (21, 37, 373) that drives the pump rotor and a member (35) through which the drive shaft portion passes. 7. A fluid machine as claimed in any one of claims 3 to 6, wherein the pump rotor is provided with a one-side slit (6sa1, 6sb1) extending in the radial direction of the pump rotor through a central axis of the pump rotor on one side of the supported portion in the axial direction, and a other-side slit (6sa2, 6sb2) extending in the axial direction from both radial ends of the one -side slit on the other side of the supported portion. A fluid machine as described in any one of claims 2 to 7, wherein the shaft is provided only on one side of the pump rotor in the axial direction and supported by a bearing portion (212), and is not supported by a bearing portion on the other side of the pump rotor. 9. The fluid machine according to claim 8 , wherein the bearings provided on both sides of the motor rotor in the motor section are the bearings provided on one side of the pump rotor. The fluid machinery according to any one of claims 1 to 9, which is used under an oil-free condition in which no lubricating oil is supplied from the outside. a compression chamber introduction passage (72) that communicates the suction chamber with the compression chamber;
the suction chamber includes an intake side area occupying half of the suction chamber on a side where the exterior side suction passage is located with respect to the shaft, and an outlet side area occupying half of the suction chamber on a side opposite to the intake side area,
The fluid machine according to claim 1 , wherein the compression chamber introduction passage is provided in a position of the suction chamber facing the outflow area. The fluid machine according to claim 11 , wherein the compression chamber introduction passage is located in an area of the outflow side area that includes a range rotated 180 degrees or more around the shaft in a circumferential direction of the exterior side suction passage. a passage forming member (35) provided with a compression chamber introduction passage (72) that connects the suction chamber and the compression chamber;
The fluid machine according to any one of claims 1 to 12, further comprising a rotor seal portion (19) that comes into contact with and seals the pump rotor that slides relative to the passage forming member. The fluid machine according to any one of claims 1 to 13, further comprising a communication passage (631) that communicates between the suction chamber and the inside of the motor chamber. Further, a filter (15) is provided to divide the suction chamber into two chambers,
15. The fluid machine according to claim 1, wherein the filter is arranged to filter fluid between the external suction passage (70) and a compression chamber introduction passage (72) that connects the suction chamber and the compression chamber. 16. The fluid machine according to claim 15, wherein the filter is arranged so as to filter a fluid between the external suction passage (70) and a pump rotor side end surface (212a) of the bearing portion exposed to the suction chamber. Further, a filter (15) is provided to divide the suction chamber into two chambers,
The two chambers are
A chamber on the side of the external suction passage (70);
17. The fluid machine according to claim 1, wherein the suction chamber is a chamber on the side of a compression chamber introduction passage (72) that communicates between the suction chamber and the compression chamber. The fluid machinery according to any one of claims 15 to 17, wherein the two chambers are positioned so as to be stacked in the axial direction. Further, a spacer member (831) for fixing the filter (15) is provided,
19. The fluid machine according to claim 18, wherein the filter is held between a member that defines the suction chamber and the spacer member.

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