JP2005269804A - Rotating electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reliable rotary electric machine capable of suppressing variation in bonding height of a magnet when fixing it to a rotor. <P>SOLUTION: A rotor 1 comprises a rotor core 4 provided in a magnet insert hole, a magnet 6 inserted in the magnet insert hole, and an adhesive layer for bonding the magnet to the core filled in the gap between the rotor core 4 and the magnet 6. The cross sectional area of the gap orthogonal to the insert direction of the magnet around the end face of the magnet close to the magnet insert opening is larger than that around a first cross section of the magnet positioned on depth side of the magnet insert hole. The cross sectional area of the magnet orthogonal to the insert direction of the magnet at the end face which is inserted later is preferred to be smaller than that at the end face which is inserted first. The magnet insert hole of a part of electromagnetic steel plate which is close to the magnet insert opening in the electromagnetic steel plate constituting the rotor core may be enlarged to widen the cross sectional area of the gap. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rotating electrical machine, and more particularly to a rotor of a rotating electrical machine.

  As a motor, a generator, etc. (rotary electric machine), there is a permanent magnet type synchronous rotating machine including a permanent magnet in a rotor.

  Japanese Patent Laid-Open No. 11-98735 (Patent Document 1) discloses a procedure for adhering the permanent magnet of such a permanent magnet embedded rotor.

  The above publication describes that a permanent magnet is inserted after injecting an adhesive into a slot provided in the rotor. Then, the inserted magnet rises along the permanent magnet and the inner wall of the slot by the inserted magnet, and the liquid level of the adhesive is pushed up.

Thereby, the adhesive fills the gap between the slot and the permanent magnet while wrapping the permanent magnet. Thereafter, the magnet is firmly fixed to the rotor by curing the adhesive by heat treatment or the like. Japanese Patent Application Laid-Open No. 11-98735 discloses that an uneven shape portion is provided in a slot and the unevenness portion is engaged by curing the adhesive to improve the fixing degree.
JP-A-11-98735 Japanese Patent Laid-Open No. 9-163649 JP 2001-352702 A Japanese Patent Laid-Open No. 11-252838

  FIG. 18 is a diagram for explaining a conventional manufacturing process of a rotor.

  Referring to FIG. 18, the rotor has a rotor core 104 disposed on an end plate 108. The rotor core 104 is formed by laminated electromagnetic steel plates 105.

  Each electromagnetic steel plate 105 is provided with a hole for inserting a magnet. A slot into which the holes are gathered to insert a magnet is formed. An opening of the slot is arranged upward, and a predetermined amount of adhesive 132 is dropped from the nozzle 134 into this opening.

  FIG. 19 is a view showing a state after the permanent magnet is inserted into the magnet insertion hole.

  Referring to FIGS. 18 and 19, the liquid level of adhesive 132 rises due to the insertion of a magnet. However, in the case of a permanent magnet fixing method in which such an adhesive is injected in advance and then a magnet is inserted, variation in the amount of adhesive dripping, variation in accuracy of the shape of the permanent magnet and the shape of the slot portion, etc. As a result, the liquid level of the adhesive after magnet insertion varies by Δh.

  FIG. 20 is a diagram in the case where the adhesive dripping amount varies toward the smaller one.

  In the case shown in FIG. 20, the permanent magnet and the rotor core are brought into close contact with each other by the height H filled with the adhesive. Since there is little adhesive, the portion above the height H is not filled with adhesive. In such a case, if centrifugal force is applied by rotation of the rotor, the permanent magnet in the portion not filled with adhesive Centrifugal force acting on is applied as stress as shown by the arrow in FIG.

  In this case, a very large force is applied to the electromagnetic steel sheet at the boundary portion of the adhesive liquid surface. Moreover, a crack etc. may arise in a magnet.

  FIG. 21 is a diagram illustrating a problem when the amount of adhesive dripping is too large.

  As shown in FIG. 21, when the amount of the adhesive dropped is too large, the adhesive overflows to the surface of the rotor core, and excess adhesive 110 rises. When the adhesive is cured in this state, a gap is formed between the rotor core and the end plate placed on the upper surface thereof. Further, when the overflow amount is large, there arises a problem that the adhesive protrudes from the end plate.

  As explained above, permanent magnets inserted into the rotor of the motor have variations in the adhesive application area for each slot, and those with a small application area or biased to one side are not suitable for centrifugation at high rotation. The magnet may be damaged by the load. For this reason, it is desirable to make the adhesive application area uniform for each slot.

  At present, there is a problem that the clearance between the inner wall of the slot of the motor and the rotor magnet is narrow, and when the magnet is inserted, the area where the adhesive spreads on the magnet surface of each slot is not uniform.

  In addition, it is difficult to adjust the amount of adhesive to be filled for each slot inner wall and magnet clearance, and it is desired to manage the amount of adhesive with a uniform filling amount in the process.

  An object of the present invention is to provide a rotating electrical machine that can suppress variations in the adhesion height of magnets when fixing a magnet to a rotor by injecting an adhesive, and has improved reliability.

  In summary, the present invention is a rotating electrical machine and includes a rotor that rotates around a rotation axis. The rotor includes a rotor core provided with a magnet insertion hole, a magnet inserted into the magnet insertion hole, and an adhesive layer that fills a gap between the core and the magnet and fixes the core and the magnet. The cross-sectional area of the gap perpendicular to the magnet insertion direction is larger in the periphery of the end surface portion of the magnet close to the magnet insertion port than in the periphery of the first cross section of the magnet located on the back side of the magnet insertion hole.

  Preferably, the cross-sectional area of the magnet orthogonal to the magnet insertion direction is smaller at the end surface portion of the magnet close to the magnet insertion port than the first cross-section.

  Preferably, the cross-sectional area of the magnet orthogonal to the magnet insertion direction monotonously decreases from the first cross section toward the end surface of the magnet close to the magnet insertion port.

  Preferably, the predetermined cross section of the magnet parallel to the insertion direction is a trapezoid.

  Preferably, the magnet has a first part disposed at the back of the insertion hole, and a second part divided from the first part and disposed near the insertion port of the insertion hole, and the second part. The cross-sectional area perpendicular to the insertion direction is smaller than the cross-sectional area perpendicular to the insertion direction of the first part.

  Preferably, the cross-sectional area of the magnet insertion hole orthogonal to the magnet insertion direction is larger in the magnet insertion port portion than in the portion corresponding to the first cross section.

  More preferably, an adhesive reservoir for preventing overflow of the adhesive from the magnet insertion hole is provided in the magnet insertion opening portion of the magnet insertion hole.

  More preferably, the rotor core includes a plurality of laminated electromagnetic steel plates, and the first electromagnetic steel plate corresponding to the first cross section of the plurality of electromagnetic steel plates has a first part forming a magnet insertion hole. The second electromagnetic steel plate corresponding to the magnet insertion port among the plurality of electromagnetic steel plates is provided with a second hole that is part of the magnet insertion hole and is larger than the first hole.

  Preferably, the cross-sectional area of the magnet insertion hole orthogonal to the magnet insertion direction monotonously increases from the portion corresponding to the first cross section toward the portion corresponding to the magnet insertion port.

  More preferably, the predetermined cross section parallel to the insertion direction of the magnet insertion hole is a trapezoid.

  According to this invention, even when there are variations in the amount of adhesive dripping and in the accuracy of the shape of the insertion holes of the magnet and the rotor, variations in the filling height of the adhesive can be kept relatively small. The adhesion area can be uniformly wide. This stabilizes the fixing strength of the magnet, thereby reducing variations in motor output performance, rotor strength, etc., and improving product reliability.

  Furthermore, the assembly property of the end plate is improved while preventing overflow of the adhesive.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[Embodiment 1]
FIG. 1 is an overview of a rotor 1 of a rotating electrical machine according to the first embodiment.

  Referring to FIG. 1, rotor 1 includes a shaft 2, an end plate 8, a rotor core 4, a press plate 10 that presses the rotor core 4 together with the end plate 8, and a pressure plate 12. The rotor core 4 includes a plurality of laminated electromagnetic steel plates 5.

  A flange 14 for laminating the electromagnetic steel plates 5 is formed around the shaft.

  FIG. 2 is a view of the rotor core 4 in FIG. 1 as viewed from above, and shows the shape of the electromagnetic steel plate 5.

  Referring to FIG. 2, the electromagnetic steel sheet 5 is a disk having a circular outer periphery, and a hole 29 into which the flange 14 is inserted is provided at the center. The electromagnetic steel plate 5 is further provided with eight rectangular holes 21 to 28 for inserting plate-like permanent magnets.

  FIG. 3 is a cross-sectional view in a plane including the rotation axis of the rotor 1 shown in FIG.

  FIG. 3 shows a cross section from the center of the shaft to the outer periphery of the rotor in the section III-III in FIG.

  The end plate 8 is first disposed on the flange 14 provided around the shaft 2, and the electromagnetic steel plates 5 are sequentially closely stacked thereon to form the rotor core 4. The rotor core 4 is provided with a slot for inserting a permanent magnet as shown in FIG. This slot is formed by laminating the holes 21 of the electromagnetic steel sheet 5. The permanent magnet 6 is inserted into this slot.

  The gap between the permanent magnet 6 and the electromagnetic steel plate 5 is filled with an adhesive. After the filling of the adhesive is completed and a curing process such as heating is performed, the presser plate 10 and the pressure plate 12 are arranged and crimped at the end of the flange 14 to prevent the pressure plate 12 from coming off. .

  4-6 is a figure for demonstrating the manufacturing process of the rotor of the rotary electric machine of this invention.

  First, referring to FIG. 4, a slit formed by gathering holes 21 of the electromagnetic steel sheet is formed in the rotor core 4 formed by laminating the electromagnetic steel sheets 5 on the end plate 8. A predetermined amount of the agent 32 is dropped. The adhesive 32 is, for example, an epoxy or silicon adhesive. By appropriately adjusting the viscosity of the adhesive, it is possible to prevent the adhesive from flowing out from the gaps between the laminated electrical steel sheets.

  Subsequently, as shown in FIG. 5, the permanent magnet 6 is inserted into the slit of the rotor core 4. This permanent magnet has a trapezoidal cross section in the vertical direction, and the thickness of the lower end is thicker than the thickness of the upper end.

  Subsequently, as shown in FIG. 6, when the permanent magnet 6 is completely inserted, the adhesive 32 is filled in the gap between the permanent magnet 6 and the electromagnetic steel sheet to reach a predetermined filling height. However, this filling height varies in height Δh1 depending on the amount of adhesive dropped, the shape of the magnet, and the shape of the slit.

  However, by making the shape of the permanent magnet 6 trapezoidal in cross section, the cross sectional area of the gap portion closer to the insertion hole is larger than the cross sectional area of the lower gap portion. Accordingly, the variation in height is smaller than that in the case described with reference to FIG.

  As a result, even if the variation in the amount of the adhesive dropped by the same amount occurs, the variation in height Δh1 becomes smaller than that shown in FIG.

  7-10 is a figure for demonstrating the variation of the shape of a permanent magnet.

  FIG. 7 shows the shape of the permanent magnet 6 described with reference to FIGS. In the permanent magnet 6, the plate thickness D 1 of the upper end surface near the insertion hole is smaller than the plate thickness D 2 of the lower end surface on the side to be inserted first.

  FIG. 8 shows an example of the shape of the permanent magnet that changes the plate width at the lower end and the upper end by changing the plate thickness. The permanent magnet 6A is formed such that the upper end plate width W1 is smaller than the lower end plate width W2.

  FIG. 9 is an example of the shape of a permanent magnet in which grooves having different depths are provided in the central portion of the plate so that the cross-sectional area changes.

  As shown in FIG. 9, the plate thickness is D4 at the lower end, but the plate thickness of the groove portion provided in a part of the upper end portion is D3, which is thinner than the lower end.

  FIG. 10 is an example of the shape of a permanent magnet in which one corner of a plate is scraped off. According to this, in the permanent magnet 6C, the lower side of the left front side has a width W4 and the upper side has a width W3 smaller than W4. In the right front side, the lower side is D5 with respect to the length D6 and the upper side is smaller than that.

  In any of the examples shown in FIGS. 7 to 10, the cross-sectional area monotonously decreases toward the upper end with respect to the portion inserted into the insertion hole, that is, the lower end of the permanent magnet. By setting it as such a shape, the dispersion | variation in the height with which an adhesive agent is filled becomes smaller than before.

  FIG. 11 is a diagram for explaining the effect of the rotor of the rotating electrical machine of the first embodiment.

  In FIG. 11, the shape of the permanent magnet 6 is such that the cross-sectional area of the upper end surface is made smaller than the lower end surface. For example, the plate thickness is made thinner at the upper end surface than at the lower end surface. Thereby, the clearance S1 at the upper end surface becomes larger than the clearance S2 between the permanent magnet and the rotor core at the lower end surface, and the rate of increase in the liquid level of the adhesive becomes gentler as it approaches the upper end surface. Therefore, variation Δh1 is smaller than that in the conventional case shown in FIG.

  As described above, according to the invention shown in the first embodiment, even if there is a variation in the amount of adhesive dripping and the accuracy of the shape of the magnet and rotor insertion hole, the filling height of the adhesive can be reduced. Since the variation can be suppressed to be relatively small, the adhesion area of the magnet can be uniformly widened by a plurality of magnets. This stabilizes the fixing strength of the magnet, thereby reducing variations in motor output performance, rotor strength, etc., and improving product reliability.

[Embodiment 2]
In the first embodiment, the shape of the magnet inserted into each slot is made such that the area of the lower end surface is smaller than the upper end surface, so that the cross-sectional area of the gap portion filled with the adhesive is on the upper end surface. As it gets closer, it gets bigger. On the other hand, even if the magnet itself is a rectangular parallelepiped plate shape, the same effect can be obtained by using a plurality of divided magnets.

  FIG. 12 is a diagram for explaining a magnet used in the second embodiment.

  Referring to FIG. 12, two divided permanent magnets 6E and 6D are inserted into a slot of one rotor core. The plate thickness of the permanent magnet 6D inserted later is made smaller than the plate thickness of the permanent magnet 6E inserted first into the slot.

  FIG. 13 is a diagram showing a state in which a permanent magnet is inserted in the second embodiment.

  Referring to FIG. 13, even when the sizes of the holes 21 are all equal to the gap between the permanent magnet 6 </ b> E inserted first from the slot insertion hole and the rotor core 4, the plate thickness of the permanent magnet 6 </ b> D is 6 </ b> E relative to 6 </ b> E. Since the gap is filled with the adhesive, the permanent magnet 6D has a larger cross-sectional area.

  Therefore, the variation Δh2 in the filling height of the adhesive can also be made smaller than the conventional variation Δh described with reference to FIG. Thereby, even if the variation in the dripping amount of the adhesive is equal, the variation in the filling height of the adhesive can be suppressed. This stabilizes the fixing strength of the magnet, thereby reducing variations in motor output performance, rotor strength, etc., and improving product reliability. Further, it is not necessary to pour an excessive amount of adhesive in order to suppress variations.

[Embodiment 3]
In Embodiment 1 and Embodiment 2, the variation in the filling height of the adhesive could be suppressed by devising the shape of the permanent magnet. In the third embodiment, the same effect can be obtained by devising the slot shape of the rotor core.

  FIG. 14 is a view of the rotor core according to the third embodiment viewed from the axial direction with the upper end pressing plate removed.

  Referring to FIG. 14, a state in which electromagnetic steel plate 35 is further laminated on electromagnetic steel plate 5 described in FIG. 2 is shown. The electromagnetic steel plate 35 is provided with large holes 41 to 48 corresponding to the holes 21 to 28 of the electromagnetic steel plate 5, respectively.

  FIG. 15 is a view showing a cross section of the rotor core in the XV-XV cross section in FIG. 14.

  Referring to FIG. 15, electromagnetic steel plate 5 provided with holes 21 is first laminated on the end plate, and electromagnetic steel plate 35 provided with large holes 41 is laminated thereon.

  By laminating in this way, the upper cross-sectional area of the slot into which the permanent magnet 56 is inserted becomes larger than the lower cross-sectional area. Therefore, even when the permanent magnet 56 having the same cross-sectional area at the upper end and the lower end is inserted, the gap between the permanent magnet and the slot is larger on the side closer to the insertion hole.

  More specifically, the sectional area of the gap between the upper end surface of the permanent magnet and the slot is larger than the sectional area of the gap between the lower end surface of the permanent magnet and the slot. More specifically, the gap portion between the upper end surface of the permanent magnet and the slot is a portion where the cross-sectional area of the gap between the permanent magnet and the slot is maximized.

  The cross-sectional area of the magnet insertion hole orthogonal to the magnet insertion direction monotonously increases from the back toward the magnet insertion port.

  Therefore, the variation in filling height Δh3 of the adhesive can be made smaller than the variation ΔH in filling height shown in FIG. 19 as in the case described in the first and second embodiments.

  As shown in FIG. 15, in the portion of the electromagnetic steel plate 35, the clearance between the magnet and the slot is wide, so that the variation in the filling height of the adhesive in each slot can be reduced, and at the time of high rotation due to insufficient coating area or bias. It is possible to prevent magnet breakage due to the eccentric load.

  In addition, a rotor core may be formed by laminating a plurality of electromagnetic steel sheets having holes that are gradually increased, and the cross section of the insertion hole along the magnet insertion direction may be trapezoidal.

[Embodiment 4]
FIG. 16 is a view of the rotor core used in the rotating electrical machine of the fourth embodiment when viewed from the axial direction with the presser plate removed.

  Referring to FIG. 16, in the rotor core used in the fourth embodiment, electromagnetic steel plate 65 is laminated on electromagnetic steel plate 5. The electromagnetic steel plate 65 is provided with holes 71 to 78 corresponding to the holes 21 to 28 provided in the electromagnetic steel plate 5, respectively. The hole 71 has a shape bulging greatly toward the inner peripheral side of the rotation with respect to the hole 21. The holes 72 to 78 have the same shape.

  FIG. 17 is a view showing a cross section of the rotor core taken along line XVII-XVII in FIG.

  Referring to FIG. 17, the rotor core is mostly formed by laminating electromagnetic steel plates 5, and the top several electromagnetic steel plates are the electromagnetic steel plates 65 shown in FIG. 16.

  Thereby, since the adhesive reservoir 58 is formed, even when the permanent magnet 56 having a uniform cross-sectional area is inserted, even if the amount of the adhesive is excessive, the adhesive does not overflow and the adhesive reservoir 58 is formed. Absorbed. Of course, the variation in filling height can be kept small.

  The volume of the adhesive reservoir is determined by the size of the holes in the electromagnetic steel sheet 65 and the number of laminated sheets. The volume of the adhesive reservoir is determined in consideration of variations in the dripping amount of the adhesive, variations in the processing accuracy of the permanent magnet, variations in the forming of the electrical steel sheet, and the like.

  This prevents overflow of the adhesive and improves the assembling property of the presser plate.

  As described above, according to the invention shown in the fourth embodiment, even when there are variations in the amount of adhesive dripping and in the accuracy of the shapes of the insertion holes of the magnet and the rotor, the filling height of the adhesive can be reduced. Since the variation can be suppressed to be relatively small, the adhesion area of the magnet can be uniformly widened by a plurality of magnets. This stabilizes the fixing strength of the magnet, thereby reducing variations in motor output performance, rotor strength, etc., and improving product reliability.

  In particular, even if a large amount of adhesive is dripped in order to avoid insufficient filling, the adhesive will not overflow from the insertion opening due to the insertion of the magnet.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 is an overview diagram of a rotor 1 of a rotating electrical machine according to Embodiment 1. FIG. It is the figure which looked at the rotor core 4 in FIG. 1 from the top, and is a figure which shows the shape of the electromagnetic steel plate 5. It is sectional drawing in the plane containing the rotating shaft of the rotor 1 shown in FIG. It is a figure of the 1st process for demonstrating the manufacturing process of the rotor of the rotary electric machine of this invention. It is a figure of the 2nd process for demonstrating the manufacturing process of the rotor of the rotary electric machine of this invention. It is a figure of the 3rd process for demonstrating the manufacturing process of the rotor of the rotary electric machine of this invention. This is the shape of the permanent magnet 6 described with reference to FIGS. It is an example of the shape of the permanent magnet which changes board width by changing board thickness at a lower end and an upper end. It is an example of the shape of the permanent magnet which provided the groove | channel from which a depth differs in the center part of a board so that a cross-sectional area may change. It is an example of the shape of the permanent magnet which scraped off one corner of the plate. It is a figure for demonstrating the effect of the rotor of the rotary electric machine of Embodiment 1. FIG. FIG. 5 is a diagram for explaining a magnet used in a second embodiment. It is the figure which showed the state by which the permanent magnet was inserted in Embodiment 2. FIG. It is the figure which removed the upper end pressing plate from the rotor core of Embodiment 3, and was seen from the axial direction. It is the figure which showed the cross section of the rotor core in the XV-XV cross section in FIG. It is the figure which removed the pressing plate from the rotor core used with the rotary electric machine of Embodiment 4, and was seen from the axial direction. It is the figure which showed the cross section of the rotor core in XVII-XVII of FIG. It is a figure for demonstrating the manufacturing process of the conventional rotor. It is the figure which showed the state after a permanent magnet was inserted in the magnet insertion hole. It is a figure at the time of the case where the amount of adhesive drops is small. It is a figure which shows the problem when there are too many dripping amounts of an adhesive agent.

Explanation of symbols

  21 to 29, 41 to 48, 71 to 78 holes, 1 rotor, 2 shafts, 4 rotor cores, 5, 35, 65 electrical steel, 6, 6A to 6E, 56 permanent magnets, 8 end plates, 10 presser plates, 12 Pressure plate, 14 flange, 32 adhesive, 34 nozzles.

Claims (10)

With a rotor that rotates around a rotation axis;
The rotor is
A rotor core provided with a magnet insertion hole;
A magnet inserted into the magnet insertion hole;
An adhesive layer filled in a gap between the core and the magnet and fixing the core and the magnet;
The cross-sectional area of the gap perpendicular to the insertion direction of the magnet is that of the end surface portion of the magnet close to the magnet insertion port as compared to the periphery of the first cross section of the magnet located on the back side of the magnet insertion hole. A rotating electric machine that is large around.   2. The rotating electrical machine according to claim 1, wherein a cross-sectional area of the magnet perpendicular to the magnet insertion direction is smaller at the end surface portion of the magnet near the magnet insertion port than the first cross-section.   2. The rotating electrical machine according to claim 1, wherein a cross-sectional area of the magnet orthogonal to the magnet insertion direction monotonously decreases from the first cross-section toward an end surface of the magnet close to the magnet insertion port.   The rotating electrical machine according to claim 3, wherein a predetermined cross section of the magnet parallel to the insertion direction is a trapezoid. The magnet
A first portion disposed in the back of the insertion hole;
A first portion and a second portion that is divided and disposed near the insertion port of the insertion hole;
2. The rotating electrical machine according to claim 1, wherein a cross-sectional area of the second portion orthogonal to the insertion direction is smaller than a cross-sectional area of the first portion orthogonal to the insertion direction.   2. The rotating electrical machine according to claim 1, wherein a cross-sectional area of the magnet insertion hole orthogonal to the magnet insertion direction is larger in the magnet insertion port portion than in a portion corresponding to the first cross section.   The rotating electrical machine according to claim 6, wherein an adhesive reservoir for preventing overflow of adhesive from the magnet insertion hole is provided in the magnet insertion opening portion of the magnet insertion hole. The rotor core is
Including a plurality of laminated electrical steel sheets,
The first electromagnetic steel sheet corresponding to the first cross section of the plurality of electromagnetic steel sheets is provided with a first hole that forms a part of the magnet insertion hole,
The second electromagnetic steel sheet corresponding to the magnet insertion port among the plurality of electromagnetic steel sheets is provided with a second hole that is part of the magnet insertion hole and is larger than the first hole. 6. The rotating electrical machine according to 6.   The rotation according to claim 1, wherein a cross-sectional area of the magnet insertion hole orthogonal to the magnet insertion direction monotonously increases from a portion corresponding to the first cross section toward a portion corresponding to the magnet insertion port. Electric.   The rotating electrical machine according to claim 9, wherein a predetermined cross section of the magnet insertion hole parallel to the insertion direction is a trapezoid.

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