CN111133198A

CN111133198A - Fluid machine and method for disassembling shaft sleeve thereof

Info

Publication number: CN111133198A
Application number: CN201880063217.3A
Authority: CN
Inventors: 野口透; 坂口广宣
Original assignee: Kobe Steel Ltd
Current assignee: Shengang Compressor Co.,Ltd.
Priority date: 2017-09-28
Filing date: 2018-09-19
Publication date: 2020-05-08
Anticipated expiration: 2038-09-19
Also published as: JP2019065718A; CN111133198B; JP6735259B2; WO2019065404A1

Abstract

A screw compressor (1) is provided with: a rotor case (10) defining a rotor chamber (S1) for accommodating the screw rotor body (16 a); a shaft portion (16 c) that extends from the screw rotor body (16 a) through the rotor case (10); a bearing (18) that rotatably supports the shaft (16 c) outside the rotor chamber (S1); a bearing cover (19) which is a cylindrical member disposed around the shaft portion (16 c) at intervals in the radial direction of the shaft portion (16 c), is disposed on the opposite side of the rotor chamber (S1) with respect to the bearing (18) in the axial direction of the shaft portion (16 c), and regulates movement of the bearing (18); a sleeve (22) which is a cylindrical member fitted to the shaft (16 c) by interference fit; and a lip seal (23) that seals between the bearing cover (19) and the shaft sleeve (22). A step portion (22 a) having a step in the radial direction is provided in a portion of the sleeve (22) opposite to the side where the bearing (18) is located in the axial direction.

Description

Fluid machine and method for disassembling shaft sleeve thereof

Technical Field

The invention relates to a fluid machine and a method for disassembling a shaft sleeve (sleeve) of the fluid machine.

Background

In a screw compressor, which is an example of a fluid machine, a shaft portion extends to the outside of a rotor chamber, and therefore a through hole is provided in a rotor case defining the rotor chamber. Therefore, a sealing device is required to prevent the fluid from leaking from the inside of the rotor chamber to the outside through the through hole. For example, patent document 1 discloses a screw compressor provided with such a sealing device.

In the screw compressor of patent document 1, a sealing device is disposed between a bearing on the low pressure side and the motor. The sealing device is housed in a bearing housing that is detachable from the rotor case, from the viewpoint of improving maintainability. That is, the bearing housing can be removed and the sealing device can be replaced during maintenance.

Examples of the sealing device of the screw compressor include a non-contact type seal and a contact type seal. In particular, as a contact type seal, a teflon (registered trademark) lip seal which is excellent in durability, high-speed performance, and pressure resistance and is inexpensive has become mainstream in recent years. The material is made by adding a filler such as carbon or glass to teflon (registered trademark). This material may improve the wear resistance of the lip seal, and may wear the mating material (shaft material) of the lip seal. Therefore, a sleeve having a high hardness such as hardened steel or bearing steel is often provided on the mating member (shaft portion) with which the lip seal contacts.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2008-121479.

Disclosure of Invention

Problems to be solved by the invention

The sealing device of the screw compressor disclosed in patent document 1 has a structure in which a shaft sleeve is fitted to a shaft portion of a screw rotor, and a lip seal is in contact with the shaft sleeve. In such a structure, the shaft portion and the sleeve are usually fitted by interference fit in order to prevent leakage of fluid from between the shaft portion and the sleeve.

It is not easy to detach the sleeve fitted by interference fit. When such a sleeve is removed, the sleeve needs to be burned by a burner or the like to thermally expand the sleeve, which makes the operation troublesome. Further, in such a removal operation of the sleeve, the bearing adjacent to the sleeve may be heated. If the bearing is excessively heated, it is deformed, and there is a case where the size is changed and the bearing cannot be reused, in which case the bearing needs to be replaced. Therefore, the number of man-hours and cost involved in replacing the bearing in addition to the shaft sleeve are also increased.

The invention provides a fluid machine capable of easily detaching a shaft sleeve of a sealing device and a method for detaching the shaft sleeve thereof.

Means for solving the problems

The invention according to claim 1 provides a fluid machine including: a rotor case defining a rotor chamber for accommodating the screw rotor body; a shaft portion extending from the screw rotor body through the rotor case; a bearing rotatably supporting the shaft outside the rotor chamber; a bearing cover which is a cylindrical member disposed around the shaft portion with a space therebetween in a radial direction of the shaft portion, is disposed on an opposite side of the rotor chamber from the bearing in an axial direction of the shaft portion, and regulates movement of the bearing; a sleeve which is a cylindrical member fitted to the shaft portion by interference fit; and a lip seal for performing shaft sealing between the bearing housing and the shaft sleeve; the sleeve is provided with a step portion having the step in the radial direction at a portion opposite to the side where the bearing is located in the axial direction.

According to this configuration, since the axial withdrawal force can be applied to the boss through the stepped portion of the boss, the boss can be easily withdrawn from the shaft portion without heating and thermally expanding the boss burner or the like. Therefore, there is no fear of thermal deformation of the bearing, and there is no longer any unnecessary replacement of the bearing. In the above structure, the seal device is constituted by at least the lip seal and the shaft sleeve. In such a sealing device, the lip seal may be in contact with the shaft sleeve, and the shaft sleeve may be worn. Therefore, since the sleeve needs to be replaced as the sleeve is worn, a structure that allows the sleeve to be easily removed without thermally deforming the bearing is useful.

The step portion may be a recess having a shape recessed inward in the radial direction.

According to this structure, the axial withdrawal force can be applied to the boss through the recess. In particular, since the stepped portion is a concave portion, the stepped portion can be easily formed by cutting an existing sleeve or the like.

The step portion may be a projection having a shape projecting toward the radially outer side.

According to this structure, the axial withdrawal force can be applied to the boss through the convex portion. In particular, since the step portion is a convex portion, a necessary step can be secured by adjusting the height and width of the convex portion. Therefore, a required extraction force can be easily applied to the sleeve, and the sleeve can be extracted by various methods of adding an extraction force to the convex portion.

When the bearing cap is pulled out in the axial direction, the height of the convex portion may be a height of abutting against the bearing cap. The height of the convex portion may be such that a surface of the convex portion on the side where the bearing is located in the axial direction can abut against the bearing housing. Further, the convex portion may be provided at a position where a surface of the convex portion on the side where the bearing is located in the axial direction abuts against the bearing housing when the bearing housing is pulled out in the axial direction.

According to these configurations, when the bearing cap is removed by being pulled out in the axial direction, or when the shaft sleeve is removed by being pulled out in the axial direction, the bearing cap abuts against the shaft sleeve, so that the pull-out force can be applied to both the bearing cap and the lip seal. Therefore, the bearing cover and the sleeve can be removed together, and the removal operation can be simplified.

The bearing housing may further include a removal member capable of removing the lip seal together with the bearing housing; the take-out member is attached to the bearing housing, is disposed on the same side as the rotor chamber with respect to the lip seal in the axial direction, and moves in the axial direction together with the bearing housing to abut against the lip seal.

According to this configuration, when the bearing housing is removed by being pulled out in the axial direction, the removal member comes into contact with the lip seal, so that the pulling-out force can be applied to both the bearing housing and the lip seal. Therefore, the bearing cover and the sleeve can be removed together, and the removal operation can be simplified.

The bearing housing may have a flange portion for attachment to the rotor case; the flange portion is provided with a screw hole for a machine bolt for detaching the bearing cover from the rotor case.

According to this configuration, the machine bolt can be inserted into the screw hole of the flange portion, and a gap can be provided between the bearing housing and the rotor case like a screw jack. Then, the bearing cap is pulled by the gap, whereby the bearing cap can be detached from the rotor case.

A 2 nd aspect of the present invention provides a method of removing a sleeve provided in the fluid machine, wherein a hook is hooked to the stepped portion of the sleeve, and the sleeve is pulled out by pulling the hook in the axial direction.

According to this method, since the boss includes the step portion in the fluid machine, the hook having any shape to be engaged with the step portion can be hooked to the step portion, and the pull-out force can be applied to the boss through the hook. Thus, the sleeve can be easily detached.

A 3 rd aspect of the present invention provides a method of removing a sleeve in a fluid machine, the fluid machine including: a rotor case defining a rotor chamber for accommodating the screw rotor body; a shaft portion extending from the screw rotor body through the rotor case; a bearing rotatably supporting the shaft outside the rotor chamber; a bearing cover which is a cylindrical member disposed around the shaft portion with a space therebetween in a radial direction of the shaft portion, is disposed on an opposite side of the rotor chamber from the bearing in an axial direction of the shaft portion, and regulates movement of the bearing; a sleeve which is a cylindrical member fitted to the shaft portion by interference fit; and a lip seal for performing shaft sealing between the bearing housing and the shaft sleeve; a step portion having a step in the radial direction is provided in a portion of the sleeve opposite to a side where the bearing is located in the axial direction; the step part is a convex part with a shape convex towards the radial outside; the convex portion is provided at a position where a surface of the convex portion on a side where the bearing is located in the axial direction abuts against the bearing housing when the bearing housing is pulled out in the axial direction; a take-out member capable of taking out the lip seal and the bearing cover together; the extraction member is attached to the bearing housing and is disposed on the same side as the rotor chamber with respect to the lip seal in the axial direction; the bearing housing has a flange portion for mounting to the rotor case; a flange portion provided with a screw hole for a machine bolt for removing the bearing housing from the rotor housing in the axial direction; inserting a machine bolt into the screw hole for the machine bolt to expand a gap between the bearing housing and the rotor case; hooking a hook member to the gap, pulling the hook member in the axial direction to pull the bearing cover in the axial direction, and moving the lip seal in the axial direction together with the bearing cover by the take-out member coming into contact with the lip seal along with the movement of the bearing cover; the bearing cover is moved in the axial direction to bring the bearing cover into contact with the convex portion of the shaft sleeve, thereby removing the bearing cover, the lip seal, and the shaft sleeve together.

According to this method, in the fluid machine, the bearing cover can be easily removed from the rotor housing by the machine bolt and the hook, and the bearing cover, the lip seal, and the shaft sleeve can be removed together by pulling the bearing cover in the axial direction. Therefore, the disassembling operation can be simplified.

A 4 th aspect of the present invention provides a method of removing a sleeve in a fluid machine, the fluid machine including: a rotor case defining a rotor chamber for accommodating the screw rotor body; a shaft portion extending from the screw rotor body through the rotor case; a bearing rotatably supporting the shaft outside the rotor chamber; a bearing cover which is a cylindrical member disposed around the shaft portion with a space therebetween in a radial direction of the shaft portion, is disposed on an opposite side of the rotor chamber from the bearing in an axial direction of the shaft portion, and regulates movement of the bearing; a sleeve which is a cylindrical member fitted to the shaft portion by interference fit; and a lip seal for performing shaft sealing between the bearing housing and the shaft sleeve; a step portion having a step in the radial direction is provided in a portion of the sleeve opposite to a side where the bearing is located in the axial direction; the step part is a convex part with a shape convex towards the radial outside; the convex portion is provided at a position where a surface of the convex portion on a side where the bearing is located in the axial direction abuts against the bearing housing when the bearing housing is pulled out in the axial direction; a take-out member capable of taking out the lip seal and the bearing cover together; the extraction member is attached to the bearing housing and is disposed on the same side as the rotor chamber with respect to the lip seal in the axial direction; the bearing housing has a flange portion for mounting to the rotor case; a flange portion provided with a screw hole for a machine bolt for removing the bearing housing from the rotor housing in the axial direction; moving the bearing housing in the axial direction by inserting a machine bolt into a threaded hole for the machine bolt; the extracting member abuts against the lip seal with movement of the bearing cover, and the lip seal moves in the axial direction together with the bearing cover; the bearing cover is moved in the axial direction to bring the bearing cover into contact with the convex portion of the shaft sleeve, thereby removing the bearing cover, the lip seal, and the shaft sleeve together.

According to this method, in the fluid machine, the bearing cap can be easily detached from the rotor housing by the machine bolt, and the bearing cap, the lip seal, and the shaft sleeve can be detached together by pulling the bearing cap in the axial direction. Therefore, the disassembling operation can be simplified.

Effects of the invention

According to the present invention, in the fluid machine, since the boss of the sealing device includes the stepped portion, the boss can be easily detached by applying the withdrawal force through the stepped portion.

Drawings

Fig. 1 is a partial sectional view of a screw compressor according to embodiment 1 of the present invention.

Fig. 2 is a schematic enlarged view of the vicinity of the sealing device of fig. 1.

Fig. 3 is a schematic partial cross-sectional view showing a first process 1 of the method of removing the sealing device of fig. 2.

Fig. 4 is a schematic partial cross-sectional view showing a 2 nd process of the method of removing the sealing device of fig. 2.

Fig. 5 is a schematic partial sectional view showing the vicinity of a sealing device of a screw compressor according to embodiment 2 of the present invention.

Fig. 6 shows a schematic partial cross-sectional view of a modification of the sealing device of fig. 5.

Fig. 7 is a schematic enlarged view of the vicinity of the sealing device of the screw compressor according to embodiment 3 of the present invention.

Fig. 8 is a schematic view showing a positional relationship between a sleeve and a bearing housing of a screw compressor according to embodiment 3 of the present invention.

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings.

(embodiment 1)

Fig. 1 is a partial sectional view of a screw compressor (fluid machine) 1 according to embodiment 1 of the present invention. The screw compressor 1 will be described below as an example of the fluid machine, but the present technology can be applied to a screw expander having a mechanism similar to that of the screw compressor 1, in addition to the screw compressor 1.

The screw compressor 1 includes a rotor case 10 defining a rotor chamber S1. Specifically, the rotor case 10 is divided into a main body case 11 that houses the screw rotor 16 and a discharge case 12 that houses the bearing 17. The main body casing 11 and the discharge casing 12 are fixed by screw locking, and are sealed with a gasket, not shown, so that the fluid does not leak between them. A cover 13 is attached to the discharge casing 12 on the side opposite to the main body casing 11. The cap 13 and the discharge case 12 are fixed by screw locking, and are sealed with a gasket, not shown, so that the fluid does not leak between them. Therefore, the lid 13 and the discharge casing 12 define a bearing chamber S2 that is a substantially closed space. The screw compressor 1 further includes a motor casing 14 that defines a motor chamber S3 together with the rotor casing 10. The motor 15 is accommodated in the motor chamber S3.

Inside the rotor chamber S1, a pair of male and female screw rotors 16 are housed. The main body casing 11 is provided with a suction port 11a, and the suction port 11a communicates with the left end portion of the screw rotor 16 in the drawing. The fluid is supplied into the rotor chamber S1 from the suction port 11a and compressed by the screw rotor 16. Although the discharge port is not shown in fig. 1, the fluid is discharged to the right of the screw rotor 16 in the drawing. Hereinafter, the right side of the screw rotor 16 in the drawing may be referred to as a discharge side, and the left side may be referred to as a suction side.

The screw rotor 16 includes a screw rotor body 16a formed with helical teeth (not shown) and

shaft portions

16b and 16c serving as a rotation shaft thereof. The

shaft portions

16b and 16c extend from the screw rotor body 16a to the discharge side and the suction side, respectively. The discharge-side shaft portion 16b extends through the discharge casing 12 to the bearing chamber S2, and is rotatably supported by the bearing 17 in the bearing chamber S2. The suction-side shaft portion 16c extends from the rotor chamber S1 through the body housing 11 to the motor chamber S3, and is mechanically connected to the motor 15 in the motor chamber S3. The suction-side shaft portion 16c is rotatably supported by the bearing 18 in the bearing chamber S4.

A bearing cover 19 is provided in the main body case 11 at a position adjacent to the bearing 18, and the bearing cover 19 is a substantially cylindrical member disposed around the shaft portion 16c with a space in the radial direction of the shaft portion 16 c. Specifically, the bearing cover 19 is disposed on the opposite side of the bearing 18 from the rotor chamber S1 in the axial direction of the shaft portion 16 c. Therefore, the position of the bearing 18 is restricted by the bearing cover 19. The bearing cover 19 is partially disposed radially inside the rotor case 10, and defines a bearing chamber S4 together with the rotor case 10. The bearing cover 19 is provided with a projection 19a projecting radially inward from the inner surface thereof, and a seal device 21 is attached adjacent to the projection 19 a. The sealing device 21 is a device for sealing the bearing chamber S4.

Fig. 2 shows a schematic enlarged view of the vicinity of the sealing device 21 of fig. 1. Fig. 2 is a schematic diagram for clarity of the description. Therefore, in fig. 2, the shape, position, and the like of each structure may not correspond to those of fig. 1.

The sealing device 21 includes: a sleeve 22 that is a substantially cylindrical member fitted to the shaft portion 16c by interference fit; and a lip seal 23 functioning as a seal member. The interference fit is defined according to JIS B0401. The sleeve 22 is provided with a convex portion (step portion) 22a having an abutment surface 22b facing the bearing 18 side at an end portion of the shaft portion 16c opposite to the side where the bearing 18 is located in the axial direction. The projection 22a has a shape that is convex toward the radially outer side of the shaft portion 16 c. In the present embodiment, the convex portion 22a is provided continuously around the shaft portion 16c by 360 °. The lip seal 23 is disposed between the bearing cover 19 and the shaft sleeve 22 so that a lip portion contacts the shaft sleeve 22, and shaft sealing is performed between the bearing cover 19 and the shaft sleeve 22. In the present embodiment, a teflon (registered trademark) lip seal is used as the lip seal 23, and a bearing steel sleeve is used as the sleeve 22. However, in the application of the present technology, the type and material of the lip seal 23 and the sleeve 22 are not particularly limited.

Further, an O-ring 20 is disposed between the bearing cover 19 and the rotor case 10 in the radial direction. The O-ring 20 has a function of preventing fluid from leaking out between the bearing housing 19 and the rotor case 10.

When viewed in the axial direction of the shaft portion 16c, the contact surface 22b of the projection 22a is in contact with the bearing housing 19 in the axial direction. That is, the height of the protruding portion 22a is set so that the interference width d between the sleeve 22 and the bearing cap 19 shown in fig. 2 is not 0 or less, and the bearing cap 19 abuts against the sleeve 22 when the bearing cap 19 is pulled out. In other words, the height of the projection 22a is a height at which a surface (contact surface 22 b) of the projection 22a on the side where the bearing 18 is located in the axial direction contacts the bearing housing 19.

The bearing cover 19 includes a take-out member 24 that comes into contact with the lip seal 23 and that is used to draw out the lip seal 23 together with the bearing cover 19. The take-out member 24 is a substantially annular member, and is attached to the inside of the bearing cover 19. The extraction member 24 is disposed on the same side as the rotor chamber S1 (see fig. 1) with respect to the lip seal 23 in the axial direction of the shaft portion 16 c. That is, in fig. 2, the extraction member 24 is disposed in the bearing chamber S4 on the side where the bearing is located with respect to the lip seal 23.

The bearing housing 19 has a flange portion 19b for attachment to the rotor case 10. The flange portion 19b is provided with a plurality of screw holes 19c for machine bolts (machine bolts) 5 (see fig. 3) for axially detaching the bearing cover 19 from the rotor case 10. The screw hole 19c penetrates the flange 19 b.

The flow of the method of removing the sleeve 22 in the sealing device 21 of the screw compressor 1 having the above-described configuration will be described below. A plurality of machine bolts 5 are provided, but one will be representatively described.

First, as shown in fig. 3, the machine bolt 5 is prepared and inserted into the screw hole 19c provided in the flange portion 19b of the bearing housing 19. The machine bolt 5 is longer than the thickness of the flange 19b and has a length to penetrate the flange 19b when inserted from the screw hole 19 c. In a state before the machine bolt 5 is inserted into the screw hole 19c shown in fig. 3, the boss 22a of the boss is disposed on the motor 15 side at a predetermined distance D from the protruding portion 19a of the bearing housing 19 in the axial direction of the shaft portion 16 c. That is, the protruding portion 22a of the sleeve 22 is disposed on the left side in the drawing at a predetermined distance D from the protruding portion 19a of the bearing cover 19 in the axial direction of the shaft portion 16 c.

Next, as shown in fig. 4, after the machine bolt 5 is deeply inserted to reach the rotor case 10, if the machine bolt is further screwed, the clearance C between the bearing housing 19 and the rotor case 10 is enlarged. The hook member 6 having an L-shaped (hook-shaped) end portion in axial cross section is inserted into the gap C, and the hook member 6 is hooked to the bearing housing 19. Then, the hook 6 is pulled in the axial direction (see an arrow in fig. 4) of the shaft portion 16c in a state where the hook 6 is hooked on the bearing cover 19, and the pulling-out force is applied, whereby the bearing cover 19 is moved in the direction. If the bearing housing 19 is moved in this direction, it is pushed by the take-out member 24 and the lip seal 23 is also moved together. When moved by a predetermined distance D (see fig. 3), the protruding portion 19a of the bearing cover 19 abuts against the abutment surface 22b of the protruding portion 22a of the sleeve 22. If the hook member 6 is further pulled in this state, the shaft sleeve 22 is pushed by the bearing cover 19 to move, that is, the bearing cover 19, the lip seal 23, and the shaft sleeve 22 are moved together. Therefore, the bearing cover 19, the lip seal 23, and the shaft sleeve 22 can be pulled out together. Here, the case where the hook member 6 has one end portion having an L-shaped axial cross section has been described, but the present invention is not limited to this, and a plurality of end portions may be provided in the circumferential direction. In this case, a plurality of end portions of the hook member 6 may be provided in rotational symmetry.

The effects obtained by the present embodiment will be described below.

According to the present embodiment, since the extracting force can be applied to the boss 22 via the contact surface 22b of the convex portion 22a of the boss 22, the boss 22 can be easily extracted from the shaft portion 16c without being heated and thermally expanded by a burner or the like. Therefore, there is no fear of thermal deformation of the bearing 18, and there is no longer any unnecessary replacement of the bearing 18. In particular, in the seal device 21 using the lip seal 23, the lip portion of the lip seal 23 may be in contact with the shaft sleeve 22, and therefore the shaft sleeve 22 may be worn. Therefore, since the sleeve 22 needs to be replaced as the sleeve 22 is worn, a structure that can easily remove the sleeve 22 without thermally deforming the bearing 18 is useful.

Further, according to the present embodiment, the required area of the abutment surface 22b can be ensured by adjusting the height and width of the convex portion 22a of the boss 22 at the time of designing the boss 22. Therefore, a required withdrawal force can be easily applied to the sleeve 22, and the sleeve can be more reliably withdrawn.

Further, according to the present embodiment, when the bearing cover 19 is removed by being pulled out in the axial direction, the bearing cover 19 abuts on the sleeve 22, so that the pulling-out force can be applied to both the bearing cover 19 and the sleeve 22. Therefore, the bearing cover 19 and the sleeve 22 can be removed together, and the removal operation can be simplified.

Further, according to the present embodiment, when the bearing cover 19 is removed by being pulled out in the axial direction, the pull-out member 24 abuts on the lip seal 23, so that the pull-out force can be applied to both the bearing cover 19 and the lip seal 23. Therefore, the bearing cover 19 and the lip seal 23 can be removed at the same time, and the removal operation can be simplified.

Further, according to the present embodiment, the machine bolt 5 can be inserted into the screw hole 19C of the flange portion 19b, and the clearance C can be provided between the bearing cover 19 and the rotor case 10 like a screw jack. Then, the bearing housing 19 can be detached from the rotor case 10 by inserting and pulling the hook member 6 into the gap C.

(embodiment 2)

The screw compressor 1 of the present embodiment shown in fig. 5 is different from that of embodiment 1 in the shape of the sleeve 22. The structure of the boss 22 is substantially the same as that of the screw compressor 1 according to embodiment 1 of fig. 2 except for the structure. Therefore, the same reference numerals are given to the same portions as those of the structure shown in fig. 2, and the description thereof is omitted.

In the present embodiment, the length of the boss 22 is longer than that of embodiment 1. Thus, in a state where the sleeve 22 is attached to the shaft portion 16c, the convex portion 22a of the sleeve 22 is exposed to the outside without being housed in the bearing housing 19.

In the present embodiment, when the boss 22 is removed, in a state where the end portion of the hook 7 having an L-shaped (hook-shaped) axial cross section at the end portion is hooked on the abutment surface 22b of the protrusion 22a, the hook 7 is pulled in the axial direction of the shaft portion 16c (see the arrow in fig. 5), and the withdrawal force is directly applied to the boss 22 via the abutment surface 22 b. Therefore, the height of the projection 22a is set to a level that allows the hook 7 to be hooked and a necessary pulling-out force to be applied. The required withdrawal force depends on the fitting strength between the boss 22 and the shaft portion 16c, but in the present embodiment, the height of the projection 22a is, for example, about 2 mm. In order to uniformly apply the pull-out force to the boss 22, a plurality of the projections 22a and L-shaped (hook-shaped) end portions of the hook 7 are preferably provided in a rotationally symmetrical manner. More preferably, the projection 22a is provided continuously around the shaft portion 16 c.

According to the present embodiment, since the extracting force can be directly applied to the boss 22, the boss 22 can be reliably extracted.

Fig. 6 shows a modification of embodiment 2. In the present modification, the boss 22 is provided with a recess 22c instead of the convex portion 22a (see fig. 5). The recess 22c has a shape recessed inward in the radial direction of the shaft portion 16 c. The depth of the recess 22c is about half the plate thickness of the boss 22. In the present embodiment, the depth of the recess 22c is about 2mm with respect to the boss 22 having a plate thickness of 5mm, for example.

According to the present modification, the withdrawal force can be applied to the boss 22 via the abutment surface 22d of the recess 22 c. In particular, when forming the boss 22, the recess 22c can be easily formed by cutting an existing boss or the like.

(embodiment 3)

The screw compressor 1 of the present embodiment shown in fig. 7 and 8 differs from that of embodiment 1 in the shape of the bearing housing 19 and the shape of the sleeve 22. The structure of the bearing housing 19 and the shaft sleeve 22 is substantially the same as that of the screw compressor 1 according to embodiment 1 of fig. 2. Therefore, the same reference numerals are given to the same portions as those of the structure shown in fig. 2, and the description thereof is omitted. In fig. 8, for clarity of illustration, only the protruding portion 19d of the bearing cover 19 and the sleeve 22 are schematically illustrated.

In the present embodiment, the convex portions 22a of the boss 22 are provided at a plurality of positions (4 in the present embodiment) around the axial center as viewed from the motor 15 side in the direction in which the boss 22 extends. The protruding portions 19d of the bearing cover 19 are also provided at a plurality of positions (4 in the present embodiment) around the shaft center as viewed from the direction in which the boss 22 extends. When the bearing housing 19 is pulled out in the axial direction, the convex portion 22a moves to a position where the abutment surface 22b of the convex portion 22a on the side where the bearing 18 is located in the axial direction abuts against the protruding portion 19d of the bearing housing 19. In this way, the shape of the convex portion 22a and the protruding portion 19d may not be provided continuously for 360 °. Preferably, the projection 22a and the projection 19d are provided so as to be rotationally symmetrical about the axial center. Therefore, the number of the convex portions 22a and the corresponding protruding portions 19a is not particularly limited.

While the present invention has been described with reference to the specific embodiments and modifications thereof, the present invention is not limited to the embodiments described above, and can be variously modified within the scope of the present invention. For example, an embodiment of the present invention may be a form in which the contents of the respective embodiments are appropriately combined. Further, for example, in embodiment 3, a plurality of projections 19d around the axial center as shown in fig. 8 are provided on the bearing cover 19, but such a plurality of projections 19d may be provided separately at the tip end portion of the cylindrical hook instead of the bearing cover 19.

Description of the reference numerals

1 screw compressor (fluid machinery)

5 mechanical bolt

6. 7 hook hanging piece

10 rotor case

11 main body case

11a suction inlet

12 discharge casing

13 cover body

14 Motor casing

15 Motor

16 helical rotor

16a helical rotor body

16b, 16c shaft portions

17. 18 bearing

19 bearing shield

19a, 19d projection

19b flange part

19c screw hole

20O-ring

21 sealing device

22 shaft sleeve

22a convex part (step part)

22b contact surface

22c concave part (step part)

23 lip seal

The part is removed 24.

Claims

1. A fluid machine characterized in that a fluid flow path is formed,

the disclosed device is provided with:

a rotor case defining a rotor chamber for accommodating the screw rotor body;

a shaft portion extending from the screw rotor body through the rotor case;

a bearing rotatably supporting the shaft outside the rotor chamber;

a bearing cover which is a cylindrical member disposed around the shaft portion with a space therebetween in a radial direction of the shaft portion, is disposed on an opposite side of the rotor chamber from the bearing in an axial direction of the shaft portion, and regulates movement of the bearing;

a sleeve which is a cylindrical member fitted to the shaft portion by interference fit; and

a lip seal for performing shaft sealing between the bearing housing and the shaft sleeve;

the sleeve is provided with a step portion having the step in the radial direction at a portion opposite to the side where the bearing is located in the axial direction.

2. Fluid machine according to claim 1,

the step portion is a concave portion having a shape concave inward in the radial direction.

3. Fluid machine according to claim 1,

the step part is a convex part having a shape convex toward the radially outer side.

4. Fluid machine according to claim 3,

when the bearing cap is pulled out in the axial direction, the height of the convex portion is a height of abutting against the bearing cap.

5. Fluid machine according to claim 3,

the height of the convex portion is a height at which a surface of the convex portion on a side where the bearing is located in the axial direction can be brought into contact with the bearing housing.

6. Fluid machine according to claim 3,

the convex portion is provided at a position where a surface of the convex portion on the side where the bearing is located in the axial direction abuts against the bearing housing when the bearing housing is pulled out in the axial direction.

7. A fluid machine according to any one of claims 4 to 6,

a take-out member capable of taking out the lip seal and the bearing cover together;

the take-out member is attached to the bearing housing, is disposed on the same side as the rotor chamber with respect to the lip seal in the axial direction, and moves in the axial direction together with the bearing housing to abut against the lip seal.

8. A fluid machine according to any one of claims 4 to 6,

the bearing housing has a flange portion for mounting to the rotor case;

the flange portion is provided with a screw hole for a machine bolt for removing the bearing cover from the rotor housing in the axial direction.

9. A method of removing a sleeve provided in a fluid machine according to any one of claims 1 to 6,

the shaft sleeve is pulled out by hooking the hook member to the stepped portion of the shaft sleeve and pulling the hook member in the axial direction.

10. A method of removing a sleeve of a fluid machine, the fluid machine including:

a rotor case defining a rotor chamber for accommodating the screw rotor body;

a shaft portion extending from the screw rotor body through the rotor case;

a bearing rotatably supporting the shaft outside the rotor chamber;

a step portion having a step in the radial direction is provided in a portion of the sleeve opposite to a side where the bearing is located in the axial direction;

the step part is a convex part with a shape convex towards the radial outside;

the convex portion is provided at a position where a surface of the convex portion on a side where the bearing is located in the axial direction abuts against the bearing housing when the bearing housing is pulled out in the axial direction;

the extraction member is attached to the bearing housing and is disposed on the same side as the rotor chamber with respect to the lip seal in the axial direction;

the bearing housing has a flange portion for mounting to the rotor case;

a flange portion provided with a screw hole for a machine bolt for removing the bearing housing from the rotor housing in the axial direction;

it is characterized in that the preparation method is characterized in that,

inserting a machine bolt into the screw hole for the machine bolt to expand a gap between the bearing housing and the rotor case;

hooking a hook member to the gap, pulling the hook member in the axial direction to pull the bearing cover in the axial direction, and moving the lip seal in the axial direction together with the bearing cover by the take-out member coming into contact with the lip seal along with the movement of the bearing cover;

the bearing cover is moved in the axial direction to bring the bearing cover into contact with the convex portion of the shaft sleeve, thereby removing the bearing cover, the lip seal, and the shaft sleeve together.

11. A method of removing a sleeve of a fluid machine, the fluid machine including:

a rotor case defining a rotor chamber for accommodating the screw rotor body;

a shaft portion extending from the screw rotor body through the rotor case;

a bearing rotatably supporting the shaft outside the rotor chamber;

the step part is a convex part with a shape convex towards the radial outside;

the bearing housing has a flange portion for mounting to the rotor case;

it is characterized in that the preparation method is characterized in that,

moving the bearing housing in the axial direction by inserting a machine bolt into a threaded hole for the machine bolt;

the extracting member abuts against the lip seal with movement of the bearing cover, and the lip seal moves in the axial direction together with the bearing cover;