Sleeve for rotor and rotor

Abstract

A sleeve for a rotor is provided with a through-hole in which a shaft in which a small-diameter shaft part and a large-diameter shaft part having different outer diameters are arranged side by side in the axial direction is fitted, the through-hole being provided with: a small-diameter hole part and a large-diameter hole part disposed at positions separated from each other in the axial direction; the small-diameter shaft part and the large-diameter shaft part are respectively embedded in a tightly attached state; and an intermediate hole section disposed between the small-diameter hole section and the large-diameter hole section, the intermediate hole section being provided with, on the inner surfaces of the small-diameter hole section and the large-diameter hole section, a groove extending from a midway position in the axial direction of the small-diameter hole section and the large-diameter hole section to the intermediate hole section. The sleeve for the rotor is provided with a hydraulic pressure supply hole formed in the inner surface of the middle hole part or the groove.

Description

Technical Field

[0001] The present invention relates to a sleeve for a rotor and a rotor. Background Art

[0002] A rotor is known that includes: a shaft having a step portion; and a sleeve that fits with the shaft (see, for example, Patent Document 1). The sleeve has a hollow portion that is arranged to cover the step portion, and has a hydraulic pressure supply hole that communicates with the hollow portion.

[0003] When assembling the rotor, the sleeve and the shaft are fitted together by shrink fitting. As a result, the sleeve and the shaft are fixed to each other by high contact pressure on both sides of the hollow part in the axial direction. When disassembling the rotor, the operator supplies hydraulic pressure into the hollow part from the hydraulic supply hole to separate the sleeve from the shaft.

[0004] Since the contact pressure between the sleeve and the shaft is high, a large hydraulic pressure needs to be supplied to the hollow portion in order to detach the sleeve from the shaft. If the sleeve expands radially due to the supply of hydraulic pressure, the contact pressure between the sleeve and the shaft is relieved and the static friction force is reduced. Moreover, the moment the axial force generated by the hydraulic pressure exceeds the static friction force, the sleeve detaches from the shaft.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Utility Model Application Laid-Open No. 5-26202 Summary of the invention

[0008] Problem that the invention aims to solve

[0009] If the hydraulic pressure supplied to the hollow portion is large in this case, the sleeve may suddenly detach from the shaft, so it is necessary to take measures to prevent the detached sleeve or the shaft from violently flying outward. Thus, it is expected that even if a large hydraulic pressure is supplied, the sleeve can be prevented from detaching suddenly from the shaft.

[0010] Solutions for solving problems

[0011] One embodiment of the present invention is a sleeve for a rotor, which has a through hole that allows a shaft with a small diameter shaft portion and a large diameter shaft portion having different outer diameters arranged along an axial direction to be fitted together. The through hole includes: a small diameter hole portion and a large diameter hole portion, which are separated and arranged along the axial direction, and allow the small diameter shaft portion and the large diameter shaft portion to be fitted together in a close contact state, respectively; and an intermediate hole portion, which forms a closed chamber supplied with hydraulic pressure between the small diameter hole portion and the large diameter hole portion, and the inner surface of the large diameter hole portion has one or more recesses isolated from the intermediate hole portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a longitudinal sectional view showing a rotor according to a first embodiment of the present invention.

[0013] Figure 2 It means composition Figure 1 A longitudinal sectional view of a sleeve of a rotor according to a first embodiment of the present invention.

[0014] Figure 3 It means in Figure 1 A longitudinal sectional view showing a state in which hydraulic pressure is supplied to a sealed chamber at position A where the shaft and the sleeve are assembled in the rotor.

[0015] Figure 4 It means from Figure 3 A longitudinal sectional view showing a state in which the hydraulic pressure is increased and the shaft moves to position B relative to the sleeve.

[0016] Figure 5 It means the axis is from Figure 4 A longitudinal sectional view of the state relative to the state where the sleeve moves to position C.

[0017] Figure 6 It means the axis is from Figure 5 A longitudinal sectional view of the state relative to the state where the sleeve moves to position D.

[0018] Figure 7 It means relative to Figures 3 to 6 A graph showing the change in hydraulic pressure of the rotor position and the volume of the closed chamber.

[0019] Figure 8 It is a longitudinal sectional view showing a rotor according to a second embodiment of the present invention.

[0020] Fig. 9 Yes means Figure 1 as well as Figure 8 A partial longitudinal sectional view of a modified example of a large diameter hole portion in a rotor.

[0021] Fig.10 Yes means Figure 1 as well as Figure 8 A partial longitudinal sectional view of another modified example of the large diameter hole portion in the rotor.

[0022] Fig.11 It means relative to Fig. 9 as well as Fig.10 A graph showing changes in the hydraulic pressure and the volume of the sealed chamber depending on the position of the rotor.

[0023] Fig.12 Yes means Figure 2 A transverse cross-sectional view of a sleeve showing a modified example of a recess in a sleeve. DETAILED DESCRIPTION

[0024] Hereinafter, a sleeve 4 and a rotor 1 according to a first embodiment of the present invention will be described with reference to the drawings.

[0025] The rotor 1 of this embodiment is a rotor for a built-in motor of, for example, an industrial machine in which a stator is assembled. Figure 1 As shown, the rotor 1 includes a main shaft (shaft) 2 and a cylindrical sleeve (rotor sleeve) 4 having a through hole 3 into which the main shaft 2 is fitted.

[0026] like Figure 1 As shown, the spindle 2 includes a small diameter shaft portion 5 and a large diameter shaft portion 6 arranged side by side along the axis O. The spindle 2 also includes an abutment surface 7 that abuts against the end surface of the sleeve 4 on the large diameter shaft portion 6 side along the axis O direction.

[0027] The small diameter shaft portion 5 and the large diameter shaft portion 6 each have a smooth cylindrical outer surface, and the outer diameter dimension D1 of the large diameter shaft portion 6 is larger than the outer diameter dimension D2 of the small diameter shaft portion 5. Between the small diameter shaft portion 5 and the large diameter shaft portion 6, a step 8 having a height corresponding to the difference ΔD / 2=(D1-D2) / 2 between the outer diameter dimensions (radii) of both sides is formed.

[0028] The core 9 is fitted to the outer surface of the sleeve 4 by shrink fitting. Side rings 10 are fixed to both ends of the core 9 along the axis O. The side ring 10 has an outer diameter larger than that of the core 9 and protects the core 9 from contacting the inner surface of the stator when the rotor 1 is inserted into the stator. In addition, the side ring 10 has a plurality of threaded holes (not shown) for fixing the weight for balancing the rotor 1.

[0029] The through hole 3 of the sleeve 4 has a large diameter hole portion 11 on one end side along the direction of the axis O, into which the large diameter shaft portion 6 of the main shaft 2 fits in a close fit. In addition, the through hole 3 of the sleeve 4 has a small diameter hole portion 12 on the other end side along the direction of the axis O, into which the small diameter shaft portion 5 of the main shaft 2 fits in a close fit. Moreover, the small diameter hole portion 12 and the small diameter shaft portion 5, and the large diameter hole portion 11 and the large diameter shaft portion 6, are respectively fitted by interference fit. In the present embodiment, the small diameter hole portion 12 and the large diameter hole portion 11 are respectively the inner surfaces of the cylinder, and the length dimensions along the direction of the axis O are substantially the same.

[0030] Furthermore, the through hole 3 of the sleeve 4 is provided with an intermediate hole portion 13 at a position sandwiched between the small diameter hole portion 12 and the large diameter hole portion 11 in the direction along the axis O. In the present embodiment, the intermediate hole portion 13 has: a length dimension along the axis O that is greater than that of the small diameter hole portion 12 and the large diameter hole portion 11; and an inner diameter dimension that is greater than that of the large diameter hole portion 11. In addition, a hydraulic pressure supply hole 14 for supplying hydraulic pressure from the outside is opened on the inner surface of the intermediate hole portion 13.

[0031] In addition, in this embodiment, if Figure 1 as well as Figure 2 As shown, the sleeve 4 is provided with a circumferential groove (recess, groove) 16 on the inner surface of the large diameter hole portion 11. The circumferential groove 16 is separated from one end of the large diameter hole portion 11 side of the intermediate hole portion 13 in the direction along the axis O by two locations of a distance L1 and a distance L2, and is isolated from the intermediate hole portion 13 and formed along the entire circumference. Each circumferential groove 16 has a groove width W and a depth G.

[0032] The position of the circumferential groove 16 may be arbitrary. In addition, the number of the circumferential grooves 16 may be one or three or more. The groove width W and the depth G of the circumferential grooves 16 may be the same or different.

[0033] The volume V of each circumferential groove 16 is set as follows.

[0034] That is, the volume V of the circumferential groove 16 is set to be larger than the difference between the cross-sectional areas of the large diameter hole portion 11 and the small diameter hole portion 12, that is, the cross-sectional area of ​​the step 8 multiplied by the distance L1 from the intermediate hole portion 13 to the circumferential groove 16.

[0035] That is, the volume V of each circumferential groove 16 is set as shown in the following formula.

[0036] V=((D1+G) 2 -D1 2 )·πW / 4>(D1 2 -D2 2 )·πL1 / 4

[0037] The following describes the operation of the sleeve 4 and the rotor 1 of the present embodiment configured as above. When assembling the rotor 1 of the present embodiment, the core and the side ring 10 are fitted to the outer surface of the sleeve 4 by shrink fitting.

[0038] Then, for the assembly of the sleeve 4, the core 9 and the side ring 10, Figure 1 The spindle 2 is inserted into the through hole 3 of the sleeve 4 from the left side to the right side by shrink fitting. The spindle 2 and the sleeve 4 can be positioned in the direction along the axis O by abutting the abutting surface 7 of the spindle 2 against the end surface of the large diameter hole 11 of the sleeve 4.

[0039] In this state, the small diameter shaft portion 5 of the main shaft 2 is fitted in a close contact state with the small diameter hole portion 12 of the sleeve 4, and the large diameter shaft portion 6 of the main shaft 2 is fitted in a close contact state with the large diameter hole portion 11 of the sleeve 4, and the main shaft 2 and the sleeve 4 are fixed to each other. As a result, a closed space is defined between the main shaft 2 and the sleeve 4. The positional relationship between the sleeve 4 and the main shaft 2 at this time is called the rotor position A.

[0040] At the rotor position A, a cylindrical first space (sealed chamber) S1 is defined between the intermediate hole 13 and the outer surface of the main shaft 2 radially opposite to the intermediate hole 13. In addition, at the position of the large-diameter hole 11, two annular second spaces S2 and S3 are defined between the circumferential groove 16 and the outer surface of the large-diameter shaft portion 6 of the main shaft 2 opposite to the circumferential groove 16. In this state, the first space S1 and the two second spaces S2 and S3 are not connected to each other, but become independent closed spaces.

[0041] When disassembling rotor 1, Figure 3 As shown, at the rotor position A, high-pressure hydraulic pressure is supplied to the first space S1 through the hydraulic pressure supply hole 14. Since the first space S1 is not connected to the second spaces S2 and S3, hydraulic pressure is initially supplied only to the first space S1.

[0042] In the first space S1, by hydraulic pressure, such as by Figure 3 As shown by arrow P1, a force acts to expand the sleeve 4 in the radial direction. In addition, as shown by arrow P2, an axial force proportional to the difference in cross-sectional area between the large diameter shaft portion 6 and the small diameter shaft portion 5 acts on the step 8 provided on the main shaft 2.

[0043] As a result, the contact pressure between the small diameter shaft portion 5 and the small diameter hole portion 12 and the contact pressure between the large diameter shaft portion 6 and the large diameter hole portion 11 are reduced, and the main shaft 2 can be easily pulled out of the sleeve 4 by the axial force generated by the hydraulic pressure.

[0044] That is, when the axial force due to the hydraulic pressure exceeds the total static friction force proportional to the contact pressure between the small diameter shaft portion 5 and the small diameter hole portion 12 and between the large diameter shaft portion 6 and the large diameter hole portion 11 , the main shaft 2 starts to be pulled out from the sleeve 4 .

[0045] Moreover, in Figure 4 , which indicates the rotor position B, which is the state where the boundary between the large diameter shaft portion 6 and the small diameter shaft portion 5 reaches the circumferential groove 16 on one side when the main shaft 2 is being pulled out from the sleeve 4. In this rotor position B, a new closed chamber is formed in which the first space S1 communicates with the second space S2 on one side, and the hydraulic pressure in the first space S1 is also supplied to the second space S2 on one side.

[0046] In addition, Figure 5 , which indicates the rotor position C, which is the state where the main shaft 2 is further pulled out from the sleeve 4. In this rotor position C, the boundary between the large diameter shaft portion 6 and the small diameter shaft portion 5 reaches the other circumferential groove 16, so the first space S1 and the two second spaces S2 and S3 are connected, and hydraulic pressure is also supplied to the second space S3. Figure 61 shows the rotor position D, which is a state where the large-diameter shaft portion 6 and the large-diameter hole portion 11 are completely disengaged from each other.

[0047] exist Figure 7 In the expression relative to Figure 3 The rotor position A to Figure 6 The hydraulic pressure in the sealed chamber and the volume of the sealed chamber change from the rotor position D to the rotor position shown in FIG. Figure 7 If the hydraulic pressure starts to be supplied at the rotor position A, the hydraulic pressure in the sealed chamber increases while maintaining the rotor position and the volume of the sealed chamber.

[0048] If the hydraulic pressure of the sealed chamber continues to increase, at the moment when the axial force generated by the hydraulic pressure exceeds the static friction force, the main shaft 2 starts to move relative to the sleeve 4 in the direction along the axis O. As a result, the volume of the sealed chamber continues to increase by the cross-sectional area of ​​the step 8 multiplied by the moving distance during the period from the rotor position A to the rotor position B. Therefore, as the volume of the sealed chamber increases, the hydraulic pressure in the sealed chamber continues to decrease.

[0049] On the other hand, if the main shaft 2 moves relative to the sleeve 4 in the direction along the axis O, the large diameter shaft portion 6 is partially pulled out from the large diameter hole portion 11, and the small diameter shaft portion 5 is partially pulled out from the small diameter hole portion 12, so that the contact area between the sleeve 4 and the main shaft 2 is reduced. As a result, the friction between the sleeve 4 and the main shaft 2 is reduced, and the extraction of the main shaft 2 relative to the sleeve 4 progresses.

[0050] Then, when the position of the main shaft 2 relative to the sleeve 4 reaches the rotor position B, the first space S1 is connected to the second space S2, so the volume of the sealed chamber increases rapidly and discontinuously, and the hydraulic pressure in the sealed chamber drops rapidly. As a result, the axial force for pulling the main shaft 2 out of the sleeve 4 drops rapidly, and the contact pressure between the sleeve 4 and the main shaft 2 increases, so that the movement of the main shaft 2 relative to the sleeve 4 is braked, and the sleeve 4 and the main shaft 2 stop relative to each other.

[0051] In this state, if the hydraulic pressure supplied to the sealed chamber is increased again, the main shaft 2 starts to be pulled out from the sleeve 4 again when the axial force based on the hydraulic pressure exceeds the static friction force between the sleeve 4 and the main shaft 2. Since the contact area between the sleeve 4 and the main shaft 2 is reduced, the pulling out starts again when the hydraulic pressure in the sealed chamber is lower than that in the case of the rotor position A.

[0052] During the period from rotor position B to rotor position C, the volume of the sealed chamber increases continuously and the hydraulic pressure in the sealed chamber decreases continuously as described above. On the other hand, the contact area between the sleeve 4 and the main shaft 2 decreases by the movement of the main shaft 2 relative to the sleeve 4 in the direction along the axis O, and the main shaft 2 is pulled out of the sleeve 4 by the balance.

[0053] Then, when the position of the main shaft 2 relative to the sleeve 4 reaches the rotor position C, the first space S1 and the second spaces S2 and S3 are connected, so the volume of the sealed chamber increases rapidly and discontinuously again, and the hydraulic pressure in the sealed chamber drops rapidly. As a result, the movement of the main shaft 2 relative to the sleeve 4 is braked, and the sleeve 4 and the main shaft 2 stop relative to each other again.

[0054] When moving from rotor position C to rotor position D, the hydraulic pressure supplied to the sealed chamber is increased again to restart the extraction. Since the contact area between the sleeve 4 and the main shaft 2 is reduced, the extraction is started when the hydraulic pressure in the sealed chamber is lower than that in the case of rotor position B.

[0055] During the period from the rotor position C to the rotor position D, the hydraulic pressure in the sealed chamber also continuously decreases, and the contact area between the sleeve 4 and the main shaft 2 decreases. Due to the balance, the main shaft 2 is pulled out of the sleeve 4.

[0056] Then, when the position of the main shaft 2 relative to the sleeve 4 reaches the rotor position D, the fitting of the large diameter shaft portion 6 and the large diameter hole portion 11 and the fitting of the small diameter shaft portion 5 and the small diameter hole portion 12 are completely disengaged, and the sealed chamber is opened to the outside space. Thus, the extraction of the main shaft 2 from the sleeve 4 is completed.

[0057] That is, according to the rotor 1 and sleeve 4 of this embodiment, the main shaft 2 is not pulled out from the sleeve 4 all at once by the hydraulic pressure supplied to the sealed chamber, but the pulling out is stopped at the positions of the two circumferential grooves 16. Moreover, the hydraulic pressure for starting to pull out the main shaft 2 from the sleeve 4 again is much smaller than the initial hydraulic pressure, so there is an advantage that the main shaft 2 can be prevented from being pulled out from the sleeve 4 with great force.

[0058] In particular, it is more effective when the difference ΔD between the outer diameters (diameters) of the large diameter shaft portion 6 and the small diameter shaft portion 5 is small. That is, by suppressing the outer diameter of the main shaft 2, the outer diameter of the rotor 1 can be suppressed, and the motor can be prevented from being enlarged. Therefore, the outer diameter of the large diameter shaft portion 6 is preferably small.

[0059] On the other hand, when a hollow hole is formed along the central axis of the spindle 2, it is preferable to ensure that the inner diameter of the hollow hole is large. Thus, a workpiece with a large outer diameter can be inserted into the hollow hole. In this case, if the outer diameter of the small diameter shaft portion 5 is small, the wall thickness of the small diameter shaft portion 5 becomes thinner, and the rigidity of the spindle 2 decreases. Therefore, the outer diameter of the small diameter shaft portion 5 is preferably large. That is, the difference ΔD between the outer diameter dimensions of the large diameter shaft portion 6 and the small diameter shaft portion 5 is preferably small.

[0060] In this case, if the difference ΔD in the outer diameter is small, the hydraulic pressure needs to be increased to obtain an axial force exceeding the static friction force. In the conventional method of pulling the main shaft 2 out of the sleeve 4 at once, the main shaft 2 is violently ejected from the sleeve 4 by using a large hydraulic pressure applied to exceed the static friction force.

[0061] In contrast, according to the present embodiment, the extraction of the spindle 2 from the sleeve 4 is stopped at each circumferential groove 16 and the extraction is restarted with a lower hydraulic pressure. Thus, the spindle 2 is extracted from the sleeve 4 in stages, which can effectively prevent the spindle 2 from violently jumping out of the sleeve 4.

[0062] Furthermore, in the rotor 1 of the present embodiment, in addition to the circumferential groove 16 provided in the large diameter hole portion 11, Figure 8 As shown in FIG. 1 , the small diameter shaft portion 5 may also be provided with a circumferential groove (recess, groove) 17 at the position where the small diameter hole portion 12 is fitted. Figure 8 In the example shown, at the rotor position A, the circumferential groove 17 is provided at a position separated by distances L3 and L4 in the direction along the axis O from the boundary between the intermediate hole portion 13 and the small diameter hole portion 12 .

[0063] Thus, at the rotor position A, at the position of the small diameter shaft portion 5, two annular third spaces S4 and S5 are defined between the circumferential groove 17 and the inner surface of the small diameter hole portion 12 opposite to the circumferential groove 17. At the rotor position A, the first space S1 and the two third spaces S4 and S5 are not communicated with each other, but are independent closed spaces.

[0064] Thus, when the boundary between the intermediate hole 13 and the small diameter hole 12 reaches the circumferential grooves 17 of the small diameter shaft portion 5 while the main shaft 2 is being pulled out of the sleeve 4 , the volume of the sealed chamber can be discontinuously increased.

[0065] The number, groove width, and depth of the circumferential grooves 17 provided in the small-diameter shaft portion 5 can also be set arbitrarily.

[0066] In addition, by setting the distances L3 = L1 and L4 = L2, the second space S2 on one side and the third space S4 on one side are connected to the first space S1 at the rotor position B, and the volume of the sealed chamber can be increased sharply. That is, compared with the case where the circumferential groove 16 is provided only in the large-diameter hole portion 11, the increase in the volume of the sealed chamber can be doubled.

[0067] Alternatively, by reducing the groove width of each circumferential groove 17, the volume of the sealed chamber can be increased by the same amount as when the circumferential groove 16 is provided only in the large diameter hole portion 11. By reducing the groove width of the circumferential groove 17, the contact area between the large diameter hole portion 11 and the large diameter shaft portion 6 and the small diameter hole portion 12 and the small diameter shaft portion 5 can be increased, so that the sleeve 4 and the main shaft 2 can be more firmly fitted.

[0068] Furthermore, by setting the distances L3≠L1 and L4≠L2, the timings at which the second space S2 and the third space S4 communicate with the first space S1 can be staggered. This can increase the number of times the spindle 2 is stopped from being pulled out of the sleeve 4.

[0069] In addition, in the present embodiment, when the second space S2, S3 or the third space S4, S5 is connected to the first space S1, the sleeve 4 and the spindle 2 are relatively stopped. Alternatively, the sleeve 4 and the spindle 2 may be decelerated instead of being relatively stopped by adjusting the size of the recess, such as the groove width W and depth G of the circumferential grooves 16, 17. Thus, the brake may be applied in the middle of pulling the spindle 2 out of the sleeve 4, and the spindle 2 may be effectively prevented from violently flying out of the sleeve 4.

[0070] In addition, Figure 8 In the example shown, the circumferential grooves 16 and 17 are provided in both the large diameter hole portion 11 of the sleeve 4 and the small diameter shaft portion 5 of the main shaft 2. However, instead, the circumferential groove 17 may be provided only in the small diameter shaft portion 5 of the main shaft 2.

[0071] In addition, in this embodiment, the case where the large diameter shaft portion 6 and the small diameter shaft portion 5 of the sleeve 4 are the inner surfaces of the cylinder is exemplified. Fig. 9 As shown, the tapered inner surface may also be a tapered inner surface in which the radial interference between the large diameter hole portion 11 and the large diameter shaft portion 6 decreases continuously along the axis O direction from the small diameter hole portion 12 toward the large diameter hole portion 11 .

[0072] Alternatively, the tapered inner surface may be such that the interference between the small diameter hole portion 12 and the small diameter shaft portion 5 decreases continuously from the small diameter hole portion 12 toward the large diameter hole portion 11 along the axis O. Alternatively, only the small diameter hole portion 12 may be a tapered inner surface.

[0073] In addition, if Fig.10 As shown, it can also be a shape in which the radial interference between the large diameter hole portion 11 and the large diameter shaft portion 6 gradually decreases along the axis O direction from the small diameter hole portion 12 toward the large diameter hole portion 11. Fig.10In the example shown, the large diameter hole portion 11 is composed of a plurality of cylindrical inner surfaces with different inner diameters. In addition, it can be a shape in which the interference between the small diameter hole portion 12 and the small diameter shaft portion 5 gradually decreases along the axis O direction from the small diameter hole portion 12 toward the large diameter hole portion 11, or only the small diameter hole portion 12 can be of this shape.

[0074] According to the above structure, when the main shaft 2 is pulled out from the sleeve 4, the interference of the fitting part between the large diameter hole 11 and the large diameter shaft part 6 or the small diameter hole 12 and the small diameter shaft part 5 becomes smaller. Therefore, the contact pressure between the sleeve 4 and the main shaft 2 decreases as the main shaft 2 is pulled out from the sleeve 4.

[0075] The results, such as Fig.11 As shown, it has the following advantages: Figure 7 Compared with the case of (dotted line), the hydraulic pressure for restarting the extraction at the rotor position B and the rotor position C can be further reduced.

[0076] In addition, in this embodiment, the circumferential groove 16 is used as the concave portion provided in the large diameter hole portion 11, but it is not limited to this. For example, instead of the circumferential groove 16 in the entire circumference, it can be a groove formed in a part of the circumference, or it can be as shown in FIG. Fig.12 As shown, a plurality of arc-shaped grooves 18 are provided at intervals in the circumferential direction. In addition, the recessed portion may not be a groove but may be, for example, a hole of any shape.

[0077] That is, in this embodiment, the inner surface of the through hole 3 may have a shape such that the volume of the sealed chamber is discontinuously increased by the hydraulic pressure supplied to the sealed chamber before the through hole 3 and the spindle 2 are disengaged. Thus, a brake can be applied in the middle of pulling out the spindle 2 from the sleeve 4, and the spindle 2 can be effectively prevented from violently flying out of the sleeve 4.

[0078] As described above, according to the sleeve 4 and the rotor 1 of the present invention, the main shaft 2 can be decelerated or stopped while being pulled out from the sleeve 4 , and the main shaft 2 can be prevented from violently jumping out of the sleeve 4 .

[0079] The embodiments of the present invention have been described in detail, but the present invention is not limited to the above-mentioned embodiments. These embodiments can be variously added, replaced, changed, partially deleted, etc. without departing from the scope of the main purpose of the invention, or without departing from the concept and purpose of the present invention derived from the contents recorded in the claims and their equivalents. For example, in the above-mentioned embodiments, the order of each action and the order of each process are shown as an example and are not limited to this. In addition, the same applies to the case where numerical values ​​or formulas are used to describe the above-mentioned embodiments.

[0080] Description of reference numerals:

[0081] 1, 20: Rotor

[0082] 2: Spindle (axis)

[0083] 3: Through hole

[0084] 4: Sleeve (rotor sleeve)

[0085] 5: Small diameter shaft

[0086] 6: Large diameter shaft

[0087] 11: Large diameter hole

[0088] 12: Small diameter hole

[0089] 13: Middle hole

[0090] 14: Hydraulic supply hole

[0091] 16, 17: Circumferential groove (recess, groove)

[0092] 18: Groove (concave)

[0093] O: Axis

Claims

1. A sleeve for a rotor, characterized in that: The rotor sleeve has a through hole, and the through hole allows a shaft having a small diameter shaft portion and a large diameter shaft portion having different outer diameters to be fitted in the shaft. The through hole includes: a small diameter hole portion and a large diameter hole portion, which are arranged separately along the axial direction and allow the small diameter shaft portion and the large diameter shaft portion to fit in a close contact state respectively; and an intermediate hole portion, which forms a closed chamber supplied with hydraulic pressure between the small diameter hole portion and the large diameter hole portion, The inner surface of the large-diameter hole portion includes one or more recessed portions isolated from the intermediate hole portion.

2. The rotor sleeve according to claim 1, characterized in that: The recessed portion is a groove provided along the circumferential direction.

3. The rotor sleeve according to claim 1 or 2, characterized in that: The volume of the recessed portion is larger than a volume obtained by multiplying a difference between a cross-sectional area of ​​the large-diameter hole portion and a cross-sectional area of ​​the small-diameter hole portion by a distance from the intermediate hole portion to the recessed portion.

4. The rotor sleeve according to any one of claims 1 to 3, characterized in that: The small diameter hole portion and the small diameter shaft portion, and the large diameter hole portion and the large diameter shaft portion are respectively fitted together by interference fit.

5. The rotor sleeve according to claim 4, characterized in that: At least one of the radial interference between the small diameter hole portion and the small diameter shaft portion and the radial interference between the large diameter hole portion and the large diameter shaft portion decreases along the axial direction from the small diameter hole portion toward the large diameter hole portion.

6. The rotor sleeve according to claim 5, characterized in that: An inner surface of at least one of the small-diameter hole portion and the large-diameter hole portion is a tapered surface in which the interference continuously changes along the axial direction.

7. The rotor sleeve according to claim 5, characterized in that: The inner surface of at least one of the small-diameter hole portion and the large-diameter hole portion has a shape in which the interference varies in stages along the axial direction.

8. A sleeve for a rotor, characterized in that: The rotor sleeve has a through hole, and the through hole allows a shaft having a small diameter shaft portion and a large diameter shaft portion having different outer diameters to be fitted in the shaft. The through hole comprises: a small diameter hole portion and a large diameter hole portion, which are arranged separately along the axial direction and allow the small diameter shaft portion and the large diameter shaft portion to be fitted in a close contact state; and an intermediate hole portion, which forms a closed chamber supplied with hydraulic pressure between the small diameter hole portion and the large diameter hole portion, The inner surface of the through hole has a shape that causes the volume of the sealed chamber to increase discontinuously before the through hole and the shaft are released from engagement with each other due to the hydraulic pressure supplied to the sealed chamber.

9. A rotor, characterized in that: have: The rotor sleeve according to any one of claims 1 to 8; and The shaft is fitted into the through hole of the rotor sleeve.

10. A rotor, characterized in that: have: A shaft having a small diameter shaft portion and a large diameter shaft portion having different outer diameters arranged in an axial direction; and A sleeve for a rotor having a through hole for fitting the shaft, The through hole includes: a small diameter hole portion and a large diameter hole portion, which are arranged separately along the axial direction and allow the small diameter shaft portion and the large diameter shaft portion to fit in a close contact state respectively; and an intermediate hole portion, which forms a closed chamber supplied with hydraulic pressure between the small diameter hole portion and the large diameter hole portion, The outer surface of the small-diameter shaft portion at a position fitted with the small-diameter hole portion includes one or more recessed portions separated from the intermediate hole portion.

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