Rotationsmaschine

Abstract

An electric compressor (1) is provided with: a bearing (20B) that supports a rotating shaft (12) of a compressor impeller (8); a support wall part (23) that supports an outer periphery of the bearing (20B); a keyway (60) formed in the bearing (20B) and the support wall part (23) and extending along a direction of a rotating shaft line (X) of the rotating shaft (12); and a key member (70) inserted into the keyway (60). The support wall part (23) is provided with an outer regulating part (42a) that can come into contact with one end part (70a) of the key member (70) inside the keyway (60). An outer ring (51) of the bearing (20B) is provided with an inner regulating part (61a) that can come into contact with another end part (70b) of the key member (70) inside the keyway (60).A distance (D) between the outer regulating part (42a) and the inner regulating part (61a) is longer than a length (L) of the wedge element (70) in the direction of the rotating shaft line (X).

Description

Technical area

[0001] The present invention relates to a rotary machine provided with a bearing that supports a rotating shaft of an impeller. Background of the state of the art

[0002] A bearing device equipped with an anti-rotation mechanism that prevents rotation of an outer ring of a bearing is known. For example, Patent Document 1 discloses an anti-rotation mechanism having an elongated hole that reaches the radial center of an outer ring through a housing that supports the outer ring with a pin inserted into the elongated hole. Patent Document 2 and Patent Document 3 each disclose a bearing device equipped with an anti-rotation mechanism in which a wedge element is inserted in a rotational shaft line direction. List of prior art patent documents Patent Document 1: Unexamined Japanese Patent Application JP 2014-152 923 A Patent Document 2: Unexamined Japanese Patent Application JP 2010-48 301 A Patent Document 3: Unexamined Japanese Patent Application: JP 2006-194 418 A Patent document 4: JP 6 680 360 B2 Patent document 5: JP 2015-218 591 A Patent document 6: US 2013 / 0 028 550 A1 Patent Document 7: JP S63-35 818 U JP 6 680 360 B2 discloses a bearing that supports a rotating shaft of a compressor impeller. A support wall portion supports an outer periphery of the bearing. A keyway is formed in an outer ring of the bearing and on the inner periphery of the bearing support portion. A key element is seated in the keyway. JP 2015-218591 A discloses an electric charging device including a bearing supporting a rotating shaft of an impeller; a bearing support member supporting an outer periphery of the bearing; a keyway formed in the bearing and the bearing support member and extending along a rotating shaft line direction of the rotating shaft; and a key member inserted into the keyway. The key member is a projection formed on a key ring. This projection is inserted into the keyway formed on the outer periphery of the outer ring and the keyway formed on the inner periphery of the bearing support member. US 2013 / 0 028 550 A1 discloses a bearing device supported by an axle box. An outer ring of the bearing includes a first keyway into which a key element is inserted. The key element has a projection that is inserted into the first keyway. The outer ring of the bearing also has a second keyway. The key element has a second projection that is inserted into the second keyway. JP S63-35 818 U discloses a bearing that supports a shaft on an outer member. The outer member has a pin element that engages a groove of an outer ring of the bearing. Summary of the inventionTechnical problem

[0003] When the bearing device described in Patent Document 1 is applied to, for example, a rotating machine, the thermal expansion force of the rotating shaft acting on the bearing device increases depending on the temperature conditions during use. As a result, the pin may be overloaded via the outer ring, causing discomfort. On the other hand, the bearing device described in Patent Document 2 or 3 has a problem in that the wedge member has an open end portion, and there is a possibility that the anti-rotation function becomes unstable depending on the application mode.

[0004] The object of the present invention is to provide a rotary machine capable of eliminating the effect of thermal expansion of a rotary shaft while stably preventing rotation of an outer ring following rotation of an inner ring of a bearing. Solution to the problem

[0005] This object is achieved by a rotary machine having the features of claim 1. Advantageous further developments are the subject of the dependent claims. Effects of the invention

[0006] According to some aspects of the present invention, it is possible to eliminate the influence of thermal expansion of a rotary shaft while stably preventing rotation of an outer ring following rotation of an inner ring of a bearing. Brief description of the drawings Fig. 1 shows a cross-sectional view of an electric compressor according to an embodiment of the present invention. Fig. 2 shows an enlarged cross-sectional view of a Fig. 1 shown bearing. Fig. 3 shows a diagram of a relationship between a key element and a keyway, where Fig. 3(a) is a cross-sectional view taken along a line III(a)-III(a) in Fig. 2 shows, and Fig. 3(b) is a cross-sectional view taken along a line III(b)-III(b) in Fig. 2 shows. Fig. 4 is an exploded perspective view showing a state where the bearing and a bearing support member are assembled. Fig. 5 shows a perspective view of a sleeve which is placed from the outside on an outer ring of the bearing. Fig. 6 is a perspective view showing a state where a bearing pusher and a coil spring (spiral spring) are mounted in the sleeve. Fig. 7 is a cross-sectional view showing a relationship between a key member and a keyway according to a modification example. Description of the embodiments

[0007] An embodiment of the present invention will be described below with reference to the accompanying drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and a repeated description will be omitted.

[0008] One aspect of the present invention relates to a rotating machine including a bearing supporting a rotating shaft of an idler, a bearing support member supporting an outer periphery of the bearing, a keyway formed in the bearing and the bearing support member and extending along a rotating shaft line direction of the rotating shaft, and a key member inserted into the keyway. The bearing includes an inner ring mounted on the rotating shaft, an outer ring supported by the bearing support member, and a rolling element disposed between the inner ring and the outer ring. The bearing support member includes an outer regulating member capable of contacting one end portion of the key member inserted into the keyway in the rotating shaft line direction. The outer ring includes an inner regulating member capable of contacting another end portion of the key member inserted into the keyway.A distance between the outer regulating part and the inner regulating part is longer than a length of the wedge element in the rotating shaft line direction.

[0009] In this rotary machine, rotation of the outer ring can be prevented by the wedge member inserted into the keyway. Specifically, movement of the wedge member inserted into the keyway in the rotating shaft line direction is regulated by the outer regulating part of the bearing support part and the inner regulating part of the outer ring. Accordingly, in this rotary machine, it is possible to prevent falling out or the like of the wedge member in the application mode and to prevent rotation of the outer ring with stability. Moreover, the distance between the outer regulating part and the inner regulating part is longer than the length of the wedge member in the rotating shaft line direction. Therefore, a gap is formed between the wedge member and at least one of the outer regulating part and the inner regulating part, and elongation due to thermal expansion of the rotating shaft can be absorbed.As a result, in this rotary machine, it is possible to eliminate the effect of thermal expansion of the rotating shaft while stably preventing rotation of the outer ring following rotation of the inner ring of the bearing.

[0010] In the rotary machine according to several possible aspects, the keyway may include an inner groove provided on an outer periphery of the outer ring and an outer groove provided on an inner periphery of the bearing support part. An insertion guide part that adjusts a circumferential (rotational) displacement of the inner groove and the outer groove, which are arranged to face each other, may be provided at one or both end portions of the key member. The insertion guide part adjusts the circumferential displacement (circumferential displacement) of the inner groove and the outer groove when the key member is pre-installed in either the inner groove or the outer groove and then inserted into the other groove. As a result, in this aspect, workability during assembly is improved.

[0011] In some aspects, the insertion guide portion may be a chamfered portion. The chamfered portion facilitates insertion into the inner groove or the outer groove, thereby facilitating circumferential displacement adjustment.

[0012] In the rotary machine according to some possible aspects, the insertion guide part may be provided at the end part on the side of the inner regulating part.

[0013] In an exemplary process for installing the bearing support member to the bearing, the wedge member may be temporarily fixed in the outer groove provided in the bearing support member, and the bearing support member may be installed on the bearing in this state. Here, once the insertion guide member is provided at the end portion of the wedge member that is on the inner adjustment part side, the circumferential displacement of the inner groove and the outer groove can be effectively adjusted during assembly.

[0014] In the rotating machine according to some possible aspects, the area where the wedge element is seated may be larger in the outer groove than in the inner groove. An inner groove that is larger than the outer groove results in a less likely increase in the size of the outer ring from the perspective of ensuring the strength of the bearing.

[0015] In contrast, when the outer groove is larger than the inner groove, an increase in the size of the outer ring of the bearing can be easily avoided, which is beneficial for a compact design of the entire bearing.

[0016] In the rotary machine according to some possible aspects, the bearing support member may include a tubular member fitted externally to the outer ring, a ring-like pressing member contacting the outer ring in the tubular member, and an elastic member elastically supporting the pressing member in the rotating shaft line direction. The pressing member (pressing means member) may include an avoidance portion that prevents the wedge member from being in the tubular member and an avoidance region formed by an inner periphery of the tubular member. The avoidance portion may have a clearance in a circumferential direction of the rotating shaft with respect to the wedge member. By means of the avoidance portion having the clearance in the circumferential direction of the rotating shaft with respect to the wedge member, the wedge member is less likely to become an obstacle when the pressing member (pressing means member) is mounted in the tubular member, thus improving the mountability.

[0017] In some aspects, the avoidance area may have a curved (arch-like) shape. The curved shape facilitates handling and leads to improved handling.

[0018] In the rotating machine according to some possible aspects, the keyway may include an inner groove provided on an outer periphery of the outer ring and an outer groove provided on an inner periphery of the bearing support member, wherein the outer groove may have a wide width at a rear side in a radial direction, and the key member may have a fall-preventing part that fits in the outer groove and protrudes in a width direction perpendicular to a longitudinal direction of the outer groove. For example, when the key member is temporarily fixed in the outer groove provided in the bearing support member and the bearing support member is installed on the bearing in this state, the key member is prevented from falling out, and thus, workability during assembly is improved. The rear side in the radial direction of the outer groove refers to the side in the centrifugal direction with respect to the rotating shaft.

[0019] An electric compressor (as an example of a rotary machine) 1 according to an embodiment is described below with reference to Fig. 1. As described in Fig. As shown in Figure 1, the electric compressor 1 is applied, for example, to an internal combustion engine of a vehicle or a ship. The electric compressor 1 is provided with a compressor part 7. The electric compressor 1 rotates a compressor impeller (an example of an impeller) 8 through cooperation between a rotor part 13 and a stator part 14 to compress a fluid such as air and generate compressed air. A motor 5 is formed by the rotor part 13 and the stator part 14.

[0020] The electric compressor 1 includes a rotary shaft 12 rotatably supported in a casing 2, and the compressor impeller 8 is fixed to an end portion (one end portion) 12a of the rotary shaft 12. The casing 2 includes a motor housing 3 in which the motor 5 (rotor portion 13 and stator portion 14) is housed, and an inverter housing 4 closing an opening at the other end side (right side in the drawing) of the motor housing 3. A compressor housing 6 housing the compressor impeller 8 is provided at one end side (left side in the drawing) of the motor housing 3. The compressor housing 6 has a suction port (suction port) 9, a scroll part (scroll section) 10, and a discharge port (discharge port) 11. Although aluminum is preferred for the motor housing 3 and the inverter housing 4 because aluminum is advantageous in terms of weight reduction, stainless steel or carbon steel, for example, may also be adopted.

[0021] The rotor part 13 is fixed to the central part of the rotating shaft 12 in a direction of a rotating shaft line X and has one or a plurality of permanent magnets (not shown) fixed to the rotating shaft 12. The stator part 14 is fixed to the inner surface of the motor housing 3 so as to surround the rotor part 13 and has a coil part (not shown) around which a conductor wire is wound. Once an alternating current flows to the coil part of the stator part 14 through the conductor wire, the rotating shaft 12 and the compressor impeller 8 are rotated together by the cooperation between the rotor part 13 and the stator part 14. As the compressor impeller 8 rotates, the compressor impeller 8 sucks outside air through the suction port 9, compresses the air through the scroll part 10, and discharges the air from the discharge port 11. The compressed air discharged from the discharge port 11 is supplied to the above-mentioned internal combustion engine.

[0022] The electric compressor 1 has two bearings 20A and 20B that rotatably support the rotating shaft 12 with respect to the housing 2. The bearings 20A and 20B are arranged to sandwich the motor 5 and support the rotating shaft 12 from both sides. The bearing 20A is provided at the end portion of the motor housing 3 on the compressor impeller 8 side. The other bearing 20B is mounted on a support wall portion 23 on the inverter housing 4 side. The support wall portion 23 protrudes inward from the inverter housing 4.

[0023] The inverter housing 4 has a mechanism for supplying a drive current to the stator part 14. The inverter housing 4 has a disc-shaped end wall part 21 that closes the opening on the other end side of the motor housing 3, and a peripheral wall part 22 that connects the outer peripheral part of the end wall part 21 and the motor housing 3. The conductor wire connected to the stator part 14 is housed in the peripheral wall part 22. The end wall part 21 is made of aluminum, for example.

[0024] As this is Fig. 2, the support wall part (example of a bearing support part) 23 is provided with a stator part (base) 41 extending from the center of the end wall part 21 to the inside in the direction of the rotary shaft line X, that is, to the side of the motor 5 (left side of the end wall part 21 in the illustration of Fig. 1), a tubular sleeve receiver 42 that further protrudes inward from the stator part 41, and a sleeve (example of a tubular part) 43 that fits externally on the sleeve receiver 42. Here, the sleeve 43 is formed integrally with the sleeve receiver 42, for example, by press fitting, screw fastening, or the like. An outer ring 51 of the bearing 20B fits in and contacts the sleeve 43. In addition, the support wall part 23 is provided with an annular pressing plate (example of a pressing device part) 44 that contacts the outer ring 51 of the bearing 20B in the sleeve 43, and a coil spring (example of an elastic part) 45 that is arranged between the stator part 41 and the pressing plate 44 in the sleeve receiver 42 and presses the pressing plate 44 against the outer ring 51. In the present embodiment, the sleeve 43 and the sleeve receiver 42 are designed as separate elements.The sleeve 43 and the sleeve receiver 42 can also be designed as one piece.

[0025] The bearing 20B is a ball bearing provided with an inner ring 52 attached to the rotating shaft 12, for example, by press fitting or clearance fitting (fitting with a gap), the above-described outer ring 51, and a rolling element 53 interposed between the inner ring 52 and the outer ring 51. The bearing 20B is supported by the support wall part 23 via the sleeve 43. The inner ring 52 rotates to follow the rotation of the rotating shaft 12. At this time, with respect to the outer ring 51, rotation following the rotation of the inner ring 52 must be prevented. The rotating shaft 12 is made of metal such as an SCM material, thermally expands depending on the temperature conditions, and elongates in the direction of the rotating shaft line X.Then, the bearing 20B moves (displaces) to follow the extension of the rotating shaft 12, and thus, a clearance that can absorb this displacement is also required. A structure that can regulate the rotation of the outer ring 51 and absorb a displacement equivalent to an extension due to thermal expansion of the rotating shaft 12 is described in detail below.

[0026] As this is the case in the Fig. 2 and Fig. As shown in Fig. 5, relative rotation of the outer ring 51 and the sleeve 43 is regulated by a key member 70 inserted into a keyway 60. The keyway 60 extends along the rotational shaft line X of the rotary shaft 12, and the key member 70 is a substantially rectangular block body inserted into the keyway 60. By inserting the key member 70 into the keyway 60, rotational movement of the key member 70 is regulated while slightly allowing movement of the key member 70 in the direction of the rotational shaft line X.

[0027] As this is the case in the Fig. 3 and Fig. 4, the keyway 60 has an inner groove 61 provided on the outer periphery of the outer ring 51 and an outer groove 62 provided on the inner periphery of the sleeve 43 (the keyway 60 includes the inner groove and the outer groove). Here, one of both end parts of the outer ring 51 along the direction of the rotational shaft line X is an end part on one side that is fitted in the sleeve 43, and the other end part is an end part on the opposite side along the direction of the rotational shaft line X. In other words, one end part of the outer ring 51 is an end part on the side opposite to the compressor impeller 8 (end part on the right side in Fig. 1), and the other end part is an end part on the side of the compressor impeller 8 (end part on the left side in Fig. 1). In this case, the inner groove 61 is formed to cut out a part of one end portion of the outer ring 51. The width of the inner groove 61, that is, the dimension in a direction perpendicular to the rotational shaft line X, corresponds to the width of the wedge member 70. In other words, the width of the inner groove 61 is a width at which the wedge member 70 is seated and at which the rotational direction movement of the wedge member 70 can be regulated. Furthermore, the length of the inner groove 61, that is, the dimension in a direction along the rotational shaft line X, may be a length at which a part of the wedge member 70 is seated in the longitudinal direction (the direction of the rotational shaft line X).

[0028] The outer groove 62 is provided on the inner circumference of the sleeve 43 and extends along the rotational shaft line X. Furthermore, the outer groove 62 traverses the inner circumference of the sleeve 43 for the purpose of linear communication from the end part on the side where the bearing 20B is inserted into the inner circumference of the sleeve 43 to the end part on the opposite side. The width of the outer groove 62 corresponds to the width of the wedge element 70 and is a width at which the wedge element 70 is seated, and a rotational movement of the wedge element 70 can be regulated. The length of the outer groove 62 substantially coincides with the length of the sleeve 43 along the rotational shaft line X. Furthermore, for example, the depth of the outer groove 62 is deeper than the depth of the inner groove 61.

[0029] The inner groove 61 and the outer groove 62 overlap each other, and a keyway 60 is formed by the inner groove 61 and the outer groove 62 combined with each other. The key member 70, which is inserted into the keyway 60, is provided with an inner engagement part 71 close to the rotary shaft 12 and an outer engagement part 72 on the opposite side (see Fig. 3(a)). The entire outer engagement part 72 is fitted in the outer groove 62 in a direction along the rotation shaft line X (longitudinal direction). On the other hand, only a part of the inner engagement part 71 is fitted in the inner groove 61 in the longitudinal direction. In other words, the area where the wedge element 70 is fitted in the keyway 60 is larger in the outer groove 62 than in the inner groove 61. Moreover, in the present embodiment, the depth of the outer groove 62 is deeper than the depth of the inner groove 61. In other words, the area of ​​the wedge element 70 that is fitted in the keyway 60 is larger in the outer groove 62 than in the inner groove 61 even when the length of the inner groove 61 is extended in the longitudinal direction and the entire inner engagement part 71 of the wedge element 70 is fitted in the inner groove 61.

[0030] For example, in another embodiment, the area of ​​the wedge member 70 fitted in the keyway 60 may be larger in the inner groove 61 than in the outer groove 62, which is contrary to the present embodiment. However, an inner groove 61 larger than the outer groove 62 is likely to result in an increase in the size of the outer ring 51 from the viewpoint of ensuring the strength of the bearing 20B. In contrast, if the outer groove 62 is larger than the inner groove 61 as in the present embodiment, an increase in the size of the outer ring 51 of the bearing 20B can be easily avoided, which is advantageous in terms of compacting the entire bearing 20B.

[0031] As this is the case in the Fig. 2, Fig. 4 and Fig. As shown in Fig. 6, in the sleeve 43 fitted from the outside to the outer ring 51, there are disposed the pressing plate 44 in contact with the outer ring 51 and the coil spring (spiral spring) 45 that presses the pressing plate 44 toward the outer ring 51. The pressing plate 44 is ring-shaped, and a center hole 44D, into which an end portion of the rotary shaft 42 is inserted, is formed in the pressing plate 44. The pressing plate 44 has a spring receiving surface 44A that receives the coil spring 45. A rib 44b projecting along the outer edge is provided on a surface on a side opposite to the spring receiving surface 44a, that is, a surface facing the outer ring 51. The end portion of the rib 44b is in contact with the outer ring 51.

[0032] The pressing plate 44 is provided with an avoidance part 44c that avoids the wedge element 70 in the sleeve 43. The avoidance part 44c contacts the wedge element 70 and prevents the wedge element 70 from falling out in cooperation with the inner groove 61. The avoidance part 44c has a shape in which, for example, a region formed by a circular arc and a chord is cut away from the circular pressing plate 44. As a result, an arc-like avoidance region Ar is formed between the avoidance part 44c of the pressing plate 44 and the inner circumference of the sleeve 43. In other words, "arc-like" means a part surrounded by an outer line with a convex curve part (circular arc) and a linear part connecting both end parts of the convex curve part when viewed from a direction along the rotation shaft line X.The cross section of the avoidance region Ar is larger than at least the cross-sectional area of ​​the wedge member 70, and specifically, forms a gap in the circumferential direction of the rotary shaft 12 with respect to the wedge member 70. By providing the avoidance region Ar, the wedge member 70 is unlikely to become an obstacle when the pressing plate 44 is mounted in the sleeve 43, and thus, the assembleability is improved. In addition, the other part of the pressing plate 44 except the avoidance region Ar, that is, the other part of the outer periphery of the pressing plate 44 except the avoidance part 44c, extends radially outward beyond the wedge member 70. Specifically, the distance from the rotary shaft line X to the other part except the avoidance part 44c is longer than the distance from the rotary shaft line X to the avoidance part 44 in contact with the wedge member 70.As a result, when the pressing plate 44 is ready to rotate, the pressing plate 44 receives engagement of the wedge member 70, and its rotation is regulated. In other words, by providing the avoidance region Ar, rotation of the pressing plate 44 relative to the wedge member 70 can be regulated. It should be noted here that the shape of the avoidance region Ar is not limited to the arc-like shape in that the shape of the avoidance region Ar has any of the following functions: preventing interference during assembly of the wedge member 70, and preventing relative rotation of the pressing plate 44. However, when the curved (arc-like) shape is adopted, workability is improved compared to complex shapes.As a result, it is possible to easily form the avoidance region Ar having both functions of preventing interference with the wedge member 70 during assembly of the press plate 44 and preventing rotation of the press plate 44 relative to the wedge member 70.

[0033] As described above, the support shaft part 23 has the sleeve receiver (sleeve receiving member) 42, on which the sleeve 43 is externally seated. The end surface of the sleeve receiver 42 is capable of contacting, by facing, an end portion 70a of the rectangular block-shaped wedge member 70 in the longitudinal direction (direction along the rotation shaft line X). In other words, the end surface is an external regulating portion 42a (see Fig. 3(b)), which regulates movement of the wedge element 70 in a direction along the rotational shaft line X. Furthermore, the outer ring 51 has a wall surface that closes the back of the inner groove 61 in the direction of the rotational shaft line X, and this wall surface is capable of coming into contact with the other end part 70b of the wedge element 70 by facing it. In other words, this wall surface is an inner regulating part 61a that regulates the direction of the wedge element 70 along the rotational shaft line X. The term "capable of coming into contact" means that contact-based movement regulation is possible in a case where the wedge element 70 moves in the longitudinal direction of the keyway 60 (direction along the rotational shaft line X).

[0034] A distance D between the outer regulating part 42a and the inner regulating part 61a is longer than a length L of the wedge member 70 in the longitudinal direction. Therefore, a gap is formed between the wedge member 70 and at least one of the outer regulating part 42a and the inner regulating part 61a. Longitudinal stretching (elongation) attributable to thermal expansion (thermal expansion) of the rotary shaft 12 can be absorbed by this gap. For example, the longitudinal stretching (elongation) ΔH attributable to thermal expansion of the rotary shaft 12 is expressed by the following equation (1). ΔH=H×a×T H: Intermediate bearing distance (see Fig. 1) A: linear expansion coefficient of the rotating shaft T: Increase in temperature of the predetermined representative part (such as the bearing shaft and the bearing) before and after operation

[0035] In the present embodiment, the difference D - L between the distance D between the outer regulating part 42a and the inner regulating part 61a and the length L of the wedge member 70 in the longitudinal direction is set to be greater than the longitudinal elongation ΔH calculated by the above-mentioned equation based on thermal expansion. In other words, the length L and the distance D can be appropriately set to satisfy the following: (Distance D - Length L) > ΔH = H × a × T.

[0036] As this is the case in the Fig. 3 and Fig. 4, the wedge member 70 has a substantially rectangular block shape and is inserted into the keyway 60 such that the longitudinal direction of the wedge member 70 is along the longitudinal direction of the keyway 60. One of the two end parts of the wedge member 70 in the longitudinal direction is the end part 70a on the outer regulating part 42a side, and the other is the end part 70b on the inner regulating part 61a side. In the present embodiment, chamfered parts 70c and 70d are formed on both the end part 70a on the outer regulating part 42a side and the end part 70b on the inner regulating part 61a side. The chamfered parts 70c and 70d are examples of an insertion guide part that adjusts the circumferential displacement (displacement in the circumferential direction) of the inner groove and the outer groove 62 arranged to face each other.It is sufficient for the insertion guide part to be capable of adjusting the circumferential displacement of the inner groove 61 and the outer groove 62. Accordingly, for example, a gradient part having an inclined surface may be formed instead of the chamfered parts 70c and 70d.

[0037] The significance of providing the chamfered portions 70c and 70d as insertion guide portions will be described below. For example, when assembling the bearing 20B to the support shaft portion 23, the key member 70 may be pre-installed in the outer groove 62 of the sleeve 43 by temporarily fixing it or the like. Then, to attach (fix) the sleeve 43 of the support wall portion 23 to the bearing 20B, the groove 62 and the inner groove 61 must be aligned, and a key groove 60 with an adjusted circumferential displacement must be formed. Here, when the key member 70, temporarily fixed to the sleeve 43, is inserted into the inner groove 61 of the outer ring 51, the chamfered portion 70d of the key member 70 makes contact with the outer ring 51 to rotate the outer ring 51, and the circumferential displacement of the inner groove 61 with respect to the outer groove 62 is adjusted. As a result, handling during assembly is improved.

[0038] Furthermore, in the wedge member 70 according to the present embodiment, the chamfered portion 70c is also provided at the end portion 70a on the outer regulating portion 42a side. Accordingly, it is possible to enjoy the advantage of improving workability during assembly even in a case where the wedge member 70 is pre-installed in the inner groove 61 of the outer ring 51 and the assembly work is performed in the order opposite to that described above. In the present embodiment, the chamfered portions 70c and 70d are provided at both end portions 70a and 70b of the wedge member 70. Alternatively, an insertion guide portion such as the chamfered portions 70c and 70d may be provided at either the end portion 70a or the end portion 70b depending on the actual assembly work processes.

[0039] A modification example of the wedge element 70 and the keyway 60 is described below with reference to Fig. 7. In this modification example, the elements and structures that are the same as those of the wedge member 70 and the keyway 60 described above are denoted by the same reference numerals, and their descriptions are omitted to focus on the differences.

[0040] A keyway 60A has the inner groove 61 provided in the outer periphery of the outer ring 51 and an outer groove 62A provided on the inner periphery of the sleeve 43. The outer groove 62A has a wide width at the rear side in the radial direction. Here, the rear side in the radial direction means the outer side in the radial direction. More specifically, the rear side in the radial direction means the side facing away from the rotating shaft 12, that is, the side in the centrifugal direction with respect to the rotating shaft 12. A key member 70A has the inner engagement part 71 fitted in the inner groove 61 and an outer engagement part 72A fitted in the outer groove 62. The outer engagement part 72A is provided with a fall-out prevention part 72a protruding in the width direction perpendicular to the longitudinal direction of the outer groove 62.For example, when the wedge member 70A is temporarily fixed in the outer groove 62A and the support wall part 23 is assembled to the bearing 20B in this state, the fall-out preventing part 72 prevents the wedge member 70 from falling out by being gripped by the sleeve 43, and thus the assembling work is improved.

[0041] As described above, in the present embodiment, the rotation of the outer ring 51 can be prevented by the wedge member 70, 70A inserted into the keyway 60, 60A. Specifically, movement of the wedge member 70, 70A inserted into the keyway 60, 60A in the direction of the rotational shaft line X is regulated by the outer regulating part 42a of the support wall part 23 and the inner regulating part 61a of the outer ring 51. Therefore, in this embodiment, it is possible to prevent falling off or the like in the use mode and avoid rotation of the outer ring 51 with stability. Moreover, the distance between the outer regulating part 42a and the inner regulating part 61a is longer than the length of the wedge member 70 in the direction of the rotational shaft line X.Therefore, a gap is formed between the wedge member 70 and at least one of the outer regulating part 42a and the inner regulating part 61a, and the longitudinal extension (elongation) attributable to the thermal expansion of the rotating shaft 12 can be absorbed. As a result, in the present embodiment, it is possible to eliminate the influence of the thermal expansion of the rotating shaft 12 while stably preventing rotation of the outer ring 51 following the rotation of the inner ring 52 of the bearing 20B.

[0042] Furthermore, the present invention can be applied to any rotating machine provided with a bearing that supports a rotating shaft. For example, the present invention can be applied to an electric turbocharger that assists rotation by means of an engine provided with a turbine. Furthermore, the present invention can be applied to other general turbochargers besides the electric turbocharger. Moreover, the present invention can be applied to a turbine-based generator for electric power generation and also to a rotating machine provided with a compressor. Furthermore, the inverter housing is not limited to being axially connected to the motor housing, and it may also be connected radially outward. For example, the inverter housing may be provided at the upper part of the motor housing. List of reference symbols 1 electric compressor (rotary machine) 8 Compressor impeller (impeller) 12 rotating shaft 20B warehouse 23 Support shaft part (bearing support part) 42a External regulating part 43 Sleeve (pipe part) 44 Press plate (pressing part, pressing device part) 44c Avoidance part 51 Outer ring 52 inner ring 53 rolling element 60 keyway 61a Internal regulating part 61 inner groove 62 outer groove 70 wedge element 70c, 70d bevelled part (insertion guide part) 72a Fall-out prevention part Ar avoidance area L Length of the wedge element

Claims

[1] Rotary machine (1) with: a bearing (20B) supporting a rotating shaft (12) of an impeller (8); a bearing support member (23) supporting an outer periphery of the bearing (20B); a keyway (60) formed in the bearing (20B) and the bearing support member (23) and extending along a direction of a rotational shaft line (X) of the rotational shaft (12); and a wedge element (70) which is inserted into the keyway (60), wherein the bearing (20B) has an inner ring (52) mounted on the rotary shaft (12), an outer ring (51) supported by the bearing support member (23), and a rolling element (53) arranged between the inner ring (52) and the outer ring (51), the bearing support part (23) has an outer regulating part (42a) which can come into contact with an end part of the wedge element (70) which is inserted in the wedge groove (60) in the direction of the rotary shaft line (X), the outer ring (51) has an inner regulating part (61a) which can come into contact with another end part of the wedge element (70) which is inserted in the wedge groove (60), a distance between the outer regulating part (42a) and the inner regulating part (61a) is longer than a length of the wedge element (70) in the direction of the rotary shaft line (X), the bearing support part (23) has a tubular part (43) which sits on the outside of the outer ring (51), a ring-like pressing part (44) which is in contact with the outer ring (51) in the tubular part (43), and an elastic part which presses the pressing part (44) to the side of the outer ring (51) in the direction of the rotational shaft line (X), the pressing part (44) has an avoidance part (44c) which obstructs the wedge element (70) in the tubular part (43), a movement of the wedge element (70) in the direction of the rotary shaft line (X) is permitted, and an avoidance region (Ar) formed by an inner circumference of the pipe part (43) and the avoidance part (44c) has a clearance in a circumferential direction of the rotary shaft (12) with respect to the wedge member (70). [2] Rotary machine (1) according to claim 1, wherein the keyway (60) comprises an inner groove (61) provided on an outer circumference of the outer ring (51) and an outer groove (62) provided on an inner circumference of the bearing support part (23), and an insertion guide part (70c, 70d) which adjusts a circumferential displacement of the inner groove (61) and the outer groove (62) which are arranged to face each other is provided at one end part or at both end parts of the wedge member (70). [3] The rotary machine (1) according to claim 2, wherein the insertion guide part (70c, 70d) is a chamfered part. [4] A rotary machine (1) according to claim 2 or 3, wherein the insertion guide part (70c, 70d) is provided at the end part on the side of the inner regulating part (61a). [5] Rotary machine (1) according to one of claims 2 to 4, wherein an area in which the wedge element (70) sits is larger in the outer groove (62) than in the inner groove (61). [6] A rotary machine (1) according to claim 1, wherein the avoidance region (Ar) has an arc-like shape. [7] Rotary machine (1) according to one of claims 1 to 6, wherein the keyway (60) comprises an inner groove (61) provided on an outer circumference of the outer ring (51) and an outer groove (62) provided on an inner circumference of the bearing support part (23), the outer groove (62) has a wide width at a rear side in a radial direction, and the wedge element (70) has a fall-out prevention part (72a) which is seated in the outer groove (62) and protrudes in a width direction perpendicular to a longitudinal direction of the outer groove (62).

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