JP2008303897A - Retainer for ball bearing, and ball bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a retainer for a ball bearing capable of stably maintaining its rigidity and rotating smoothly with constant accuracy without damage over a long period of time even under a high-speed rotation environment, and to provide a ball bearing. <P>SOLUTION: The retainer 10 for a ball bearing is assembled in the ball bearing including raceway rings and a plurality of balls so as to retain the balls in pockets 8. Plate-like flat portions 2 each having a through hole 2h and concave portions 4 each concaved in a substantially semi-spherical shape from the flat portions are alternately connected so as to form an annular retainer constituent element 20. Two retainer constituent elements are arranged face to face in such a manner that the respective concave portions are depressed in reverse directions to each other and the through holes of the respective flat portions communicate with each other. The two retainer constituent elements are fixedly combined with each other by fixing members 6 inserted in the through holes and the substantially spherical spaces defined by the facing concave portions are circumferentially arranged at certain intervals, thereby constituting the pockets. When the shortest distance between the outer circumference of the retainer constituent element and the peripheral edge of the through hole is shown by d1 and the shortest distance between the inner circumference of the retainer constituent element and the peripheral edge of the through hole is shown by d2, d1 and d2 are so set as to fulfill the following formula: d1<d2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a so-called corrugated cage that is incorporated in a ball bearing and rotatably holds a plurality of balls that are rolling elements, and is particularly suitable for use in an environment where the ball bearing is rotated at a high speed. The present invention relates to a cage and a ball bearing incorporating the cage.

  Conventionally, in various ball bearings (hereinafter simply referred to as “bearings”), balls that are rolling elements that roll between races are accommodated one by one in pockets arranged at predetermined intervals in an annular cage. At the same time, it is incorporated between the bearing rings while being rotatably held, and revolves (rolls) with the cage between the bearing rings (race surfaces) of the bearings. As a result, each ball can smoothly roll between the raceways (between the raceway surfaces) without the rolling surfaces coming into contact with each other. Prevention of an increase in rotational resistance and seizure due to the occurrence of this is achieved.

At that time, there are various types of cages such as crown type, machined type, or corrugated type, and each type of cage is properly used depending on the usage and purpose of the bearing. It has been.
For example, Patent Document 1 discloses an example of a corrugated type retainer (hereinafter referred to as a corrugated retainer), and its configuration is illustrated in FIGS. As shown in FIG. 3, the corrugated cage has a structure in which two annular plate members (hereinafter referred to as a cage structure) 20 are combined, and the rivet 6 is inserted into the cage structure 20. The flat plate-like flat portion 2 having the through-holes 2h (FIGS. 5A to 5C) and the concave portion 4 recessed in a substantially hemispherical shape than the flat portion 2 are alternately connected. ing.

  In this case, the two cage structures 20 are opposed to each other so that the concave portions 4 are recessed in opposite directions and the flat portions 2 communicate with each other through the through holes 2h, and the through holes communicated with each other. By inserting the rivet 6 into 2h (hereinafter, the two through-holes 2h in this state are referred to as communication holes 22h) and crimping one end of the shaft, the two retainer components 20 are combined together. ing. By combining the two cage structures 20 in this way, the substantially spherical concave spaces formed by the opposed concave portions 4 are arranged at predetermined intervals in the circumferential direction, and the corrugated shape holding the concave spaces as pockets 8. Can be configured.

  As shown in FIGS. 4 (a) and 4 (b), the corrugated cage unites two opposing cage components 20 together by caulking one rivet 6 inserted through each communication hole 22h. It has a combined structure. In addition, in the state before caulking, each rivet 6 is provided with a head 6h set at a diameter larger than the diameter of the communication hole 22h at the base end (the lower end in FIG. 4A). In addition, a columnar shaft portion 6b set to a constant diameter slightly smaller than the diameter of the communication hole 22h is extended from the head 6h to the tip (the upper end in the figure). It has a structure.

When caulking the rivet 6 inserted through the communication hole 22h, one end portion (tip portion) of the shaft portion 6b is pressed toward the base end portion with a punch 30 or the like (FIG. 4A), and the communication hole 22h In addition to shortening the portion protruding from the diameter, the diameter is expanded (enlarged) until the diameter becomes larger than the diameter of the communication hole 22h (FIG. 5B). Further, at that time, the diameter of the portion inserted into the communication hole 22h is expanded (enlarged) until the diameter is substantially the same as the diameter of the communication hole 22h (FIG. 4B).
As a result, the rivet 6 has a caulking portion 6t formed at the tip thereof, sandwiching the two cage components 20 (flat portion 2) between the caulking portion 6t and the head 6h, and its shaft When the portion 6b is in close contact with the communication hole 22h, the two cage constituting bodies 20 are assembled and fixed integrally (FIG. 4B).

By the way, in the wave type cage having the above-described configuration, when the two cage components 20 are integrally combined (assembled) by caulking the rivet 6, the shaft of the rivet 6 inserted through the communication hole 22h. The part 6b is expanded and deformed up to the same dimension as the diameter of the communication hole 22h. Thereafter, the rivet 6 presses the shaft portion 6b in close contact with the communication hole 22h and expands the diameter of the communication hole 22h (for example, the arrow direction in FIG. 4B). That is, the corrugated cage is in a state in which a pressing force is applied from the shaft portion 6b of the rivet 6 to the communication hole 22h of the flat portion 2 (the state shown in FIG. 4B). It is disclosed in Patent Document 2 as an example that the wave cage is in such a state at the time of caulking.
For this reason, in the corrugated cage, as shown in FIG. 5A, the tensile stress in the circumferential direction remains in the vicinity of the communication hole 22h of the flat portion 2 (that is, the residual tensile stress f1 is always loaded). Is in the state).

Further, during the rotation of the bearing, as shown in FIG. 5B, the centrifugal force f2 generated along with the rotation is applied to the corrugated cage, and the corrugated cage is expanded in diameter (expanded deformation). For this reason, the wave cage is in a state in which a tensile stress f3 in the circumferential direction is generated on the whole thereof.
Therefore, when the bearing continues to rotate at a high speed and an excessive centrifugal force f2 generated along with the rotation is continuously applied to the wave cage, the inner peripheral portion where the tensile stress f3 is mechanically maximized. Therefore, the corrugated cage may be damaged (for example, broken or cracked).
JP-A-10-238544 JP-A-4-4938

  Here, in the conventional corrugated cage (each cage component 20) disclosed in Patent Document 1, the center point of the communication hole 22h (through hole 2h) is a wave as shown in FIG. On the virtual circumference concentric with the corrugated cage (each cage component 20) set to a half of the total outer diameter and inner diameter of the die cage (each cage component 20) In other words, it is positioned on a virtual circumference connecting the intermediate points in the radial direction of the cage between the outer peripheral portion and the inner peripheral portion of the corrugated cage (each cage constituent body 20).

For this reason, the shortest distance d3 (hereinafter referred to as distance d3) between the outer peripheral portion of the corrugated cage (each cage constituent body 20) and the peripheral portion of the communication hole 22h (through hole 2h), and the corrugated cage ( The shortest distance d4 (referred to as distance d4) between the inner peripheral part of each cage component 20) and the peripheral part of the communication hole 22h (through hole 2h) is set to the same distance (d3 = d4). .
Therefore, in the conventional corrugated cage, the distance d4 (that is, the distance between the peripheral portion of the communication hole 22h (through hole 2h) and the inner peripheral portion of the corrugated cage (each cage constituent body 20)) is sufficient. It is difficult to secure.

  At this time, if the distance d4 is small, the residual tensile stress f1 (FIG. 5 (a)) of the flat portion 2 generated when the rivet 6 is crimped does not stop only in the vicinity of the communication hole 22h (through hole 2h). This will affect the inner periphery of the mold cage (each cage component 20). As a result, the residual tensile stress f1 is superimposed on the inner peripheral tensile stress f3 (FIG. 5B) generated by the centrifugal force f2 (FIG. 5B) generated at the time of high-speed rotation of the bearing. , Its inner peripheral part) is liable to be damaged early (for example, breakage, cracks, etc.).

  The present invention has been made in order to solve such a problem, and its purpose is to maintain a stable rigidity without causing damage over a long period of time even in an environment where the motor is rotated at a high speed, and with a certain accuracy. It is an object of the present invention to provide a ball bearing cage (wave cage) that can continue to rotate smoothly, and a ball bearing.

  In order to achieve such an object, a ball bearing retainer according to the present invention includes at least a pair of bearing rings arranged to face each other so as to be relatively rotatable, and a plurality of balls that roll between the bearing rings. The balls are housed one by one in pockets that are incorporated in ball bearings and arranged at predetermined intervals, and are rotatably held. In such a ball bearing retainer, a flat plate-like flat portion having a through-hole through which a fixing member is inserted and a concave portion recessed in a substantially hemispherical shape from the flat portion are alternately connected to each other to form an annular retainer. Each of the through-holes that constitute the structure, the two recessed parts are opposed to each other so that the concave parts are recessed in opposite directions, and the flat parts communicate with each other through the through-holes. The pockets are configured by fixing by a fixing member inserted through a hole and combining them together and arranging substantially spherical concave spaces formed by opposing concave portions at predetermined intervals in the circumferential direction. At that time, when the shortest distance between the outer peripheral part of the cage structure and the peripheral part of the through hole is d1, and the shortest distance between the inner peripheral part of the cage structure and the peripheral part of the through hole is d2. , D1 <d2.

  In addition, the ball bearing retainer is configured such that the axial center of the fixed member after the fixing is set to a diameter that is half the total of the outer diameter and the inner diameter of the retainer structure. It is good also as a structure located near the outer peripheral part of the said retainer structure rather than the concentric virtual circumference.

  As the fixing member, a rivet can be used. In this case, the two retainer components are inserted by inserting the rivet into each of the communicating through holes and caulking one end portion of the shaft. Can be combined together.

  In order to achieve the above-described object, a ball bearing according to the present invention includes at least a pair of bearing rings opposed to each other so as to be relatively rotatable and a plurality of balls that roll between the bearing rings. Each ball is rotatably held at a predetermined interval by the above-described ball bearing cage.

  According to the present invention, by sufficiently ensuring the distance between the peripheral edge of the through hole through which the fixing member (as an example, a rivet) is inserted and the inner peripheral part of the ball bearing retainer (wave-shaped retainer), It is possible to minimize the influence on the inner peripheral portion of the residual tensile stress that occurs during assembly with a fixing member (for example, when rivets are tightened), and the inner peripheral portion is caused by centrifugal force under high-speed rotation. The rigidity with respect to the generated tensile stress can be increased. Therefore, even in an environment where the rotation is performed at a high speed, it is possible to maintain stable cage rigidity without causing damage to the corrugated cage (particularly, the inner peripheral portion) over a long period of time. As a result, the corrugated cage and the ball bearing incorporating the corrugated cage can be continuously rotated with a certain degree of accuracy, and the life of the cage can be extended.

Hereinafter, a ball bearing retainer and a ball bearing according to an embodiment of the present invention will be described with reference to the accompanying drawings. At this time, as the ball bearing retainer according to the present embodiment, a corrugated matching type is assumed, and the basic configuration is the same as that of the conventional ball bearing retainer described above (FIG. 3). For this reason, the same reference numerals are assigned to the same configurations as those of the ball bearing cage.
1 and 2 (a) and 2 (b) show a corrugated type ball bearing cage (hereinafter simply referred to as a cage) 10 according to this embodiment. In this case, the cage 10 is a ball bearing (not shown) including at least a pair of bearing rings (not shown) opposed to each other so as to be relatively rotatable and a plurality of balls (not shown) rolling between the bearing rings. The balls are housed one by one in pockets 8 arranged at predetermined intervals and held rotatably.

Note that the ball bearing into which the cage 10 is incorporated can be of any type depending on the use mode or purpose of use, but in the present embodiment, the ball bearing is a deep groove ball bearing of various sizes (hereinafter referred to as “ball cage”). As an example, a case of a bearing) is assumed. In this case, the bearing may have a single-row configuration in which only one track for rolling the ball with respect to the raceway is formed, or a double-row configuration in which two or more of the tracks are formed. Also good. Or it is good also as a structure which combined two or more bearings.
The ball size (diameter dimension) may be arbitrarily set according to the size of the bearing into which the ball is incorporated.

  As shown in FIG. 1, the cage 10 has a structure in which two annular plate members (a cage structure) 20 are combined, and the cage structure 20 penetrates the fixing member 6. A flat plate-like flat portion 2 having a hole 2h (FIGS. 5A to 5C) and a concave portion 4 that is recessed in a substantially hemispherical shape than the flat portion 2 are alternately connected. In addition, what is necessary is just to select and use various members arbitrarily for the fixing member 6 according to the usage mode and usage purpose of a bearing, the material of the holder | retainer 10, etc. FIG. For example, bolts, nuts, screws, rivets, or the like can be used. In this embodiment, a case where a rivet (hereinafter referred to as rivet 6) is used as the fixing member 6 is assumed as an example.

  The cage 10 has two cage structures 20 facing each other such that the concave portions 4 are recessed in opposite directions and the flat portions 2 communicate with each other through the through-holes 2h. The rivet 6 is inserted through the through-hole 2h (communication hole 22h), and one of the shafts is caulked so that the two cage components 20 are integrally combined. As described above, by combining the two cage structures 20, two substantially hemispherical concave portions 4 face each other to form a substantially spherical concave space, and the concave space is spaced at a predetermined interval in the circumferential direction. Can be arranged. Thereby, the holder 10 is configured with the concave space as the pocket 8.

  The size and shape of the cage structure 20 (the flat portion 2 and the concave portion 4) are arbitrarily determined according to the size and shape of the bearing into which the cage 10 constituted by the cage structure 20 is incorporated. Since it is set, there is no particular limitation here. In that case, the concave part 4 should just set to the magnitude | size and shape which can accommodate a ball one by one in the pocket 8 formed by the said concave part 4, and can hold | maintain rotatably. Moreover, what is necessary is just to provide the concave-shaped part 4 with respect to the holder | retainer structure 20 by the same number as the number of built-in balls preset based on the usage condition, purpose, etc. of the bearing in which the holder | retainer 10 is integrated. Then, the size, shape and number of the flat portions 2 are arbitrarily set and held so that the set number of concave portions 4 can be arranged at a predetermined interval (as an example, at equal intervals). What is necessary is just to comprise the container structure 20, ie, the holder | retainer 10. FIG.

As an example, in FIG. 1 and FIG. 2A, nine concave portions 4 are arranged at equal intervals so that nine balls can be rotatably held, and these concave portions 4 The structure of the holder | retainer 10 and the holder | retainer structure 20 which mutually connected with 9 flat parts 2 is shown.
Further, the material of the cage 10 (the cage structure 20) is arbitrarily set according to the use mode or purpose of the bearing in which the cage 10 (the cage structure 20) is incorporated. There is no particular limitation. For example, the cage 10 may be made of various metals such as an iron plate, a copper plate, and a stainless plate, or a resin such as a plastic plate.

In this case, the cage 10 has a structure in which two opposing cage structures 20 are integrally combined by caulking the rivets 6 inserted one by one into each communication hole 22h. When caulking the rivet 6, one end (front end) of the shaft portion 6b is pressed toward the base end with a punch 30 or the like (FIG. 4A), and the portion protruding from the communication hole 22h is shortened. At the same time, the diameter is increased (enlarged) until the diameter becomes larger than the diameter of the communication hole 22h (FIG. 5B). At that time, the diameter of the portion inserted into the communication hole 22h is expanded (enormously) until the diameter is substantially the same as the diameter of the communication hole 22h.
As a result, the rivet 6 has a caulking portion 6t formed at the tip thereof, sandwiching the two cage components 20 (flat portion 2) between the caulking portion 6t and the head 6h, and its shaft When the portion 6b is in close contact with the communication hole 22h, the two cage constituting bodies 20 can be assembled and fixed integrally (FIG. 4 (b)).

  In the present embodiment, as shown in FIG. 2B, the shortest distance between the outer periphery of the cage structure 20 and the peripheral edge of the through hole 2h is d1 (hereinafter referred to as distance d1), and the cage structure. When the shortest distance between the inner peripheral portion of 20 and the peripheral portion of the through-hole 2h is d2 (same as the distance d2), the relationship d1 <d2 is set. That is, the through-hole 2h has a virtual circumference (hereinafter referred to as a concentric circle) that is concentric with the cage structure 20 whose center point is set to a diameter that is half the total of the outer diameter and the inner diameter of the cage structure 20. (Referred to as “virtual intermediate circumference”).

Here, the sizes of the distance d1 and the distance d2, the ratio thereof, and the like are not particularly limited because they are arbitrarily set according to the size and material of the cage structure 20. However, the ratio of the size of the distance d1 and the distance d2 is sufficient rigidity (strength) even when the cage assembly 20 and the bearing in which the cage 10 in which this cage is combined are rotated at high speed. It is necessary to set it within a range where it can be secured. Therefore, in consideration of the rigidity (strength) of the cage 10 (cage component 20) during high-speed rotation of the bearing, the ratio of the distance d1 and the distance d2 is set to establish the communication hole 22h (through hole 2h). What is necessary is just to adjust the drilling position with respect to the cage radial direction.
As an example, in the present embodiment, it is assumed that the distance d2 is set to be twice as large as the distance d1 (d2 = d1 × 2) and the communication hole 22h (through hole 2h) is drilled.

  According to such a configuration, when the rivets 6 are inserted one by one into the respective communication holes 22h of the two cage structure bodies 20 opposed to each other and the rivets 6 are swaged, the rivets 6 after swaged and fixed Is positioned closer to the outer peripheral portion of the cage structure 20 than the virtual intermediate circumference (that is, closer to the outer peripheral portion of the cage 10).

  1 and 2 (a) and 2 (b), the drilling position of the communication hole 22h (through hole 2h) in the circumferential direction of the cage is the circumferential intermediate position of the flat portion 2, that is, two adjacent pockets 8. The structure of the cage 10 (the cage structure 20) set at the intermediate position in the circumferential direction of the (concave portion 4) is shown as an example, but the communication hole 22h (through hole 2h) is drilled in the circumferential direction of the cage. The position is not limited to this. For example, a communication hole 22h (through hole 2h) may be formed near one of two adjacent pockets 8 (concave portion 4).

  The formation of the through hole 2h may be performed by any method depending on the material of the cage component 20 and the like, and the method is not particularly limited. For example, when the cage structure 20 is formed by pressing various metal plates, the through holes 2h may be formed (drilled) simultaneously with the formation of the cage structure 20. Or after shape | molding the cage structure 20, you may form the through-hole 2h by drilling with respect to the said cage structure 20 after the shaping | molding.

  Thus, the inner circumference generated by the residual tensile stress f1 (FIG. 5 (a)) of the flat portion 2 generated when the rivet 6 is crimped and the centrifugal force f2 (FIG. 5 (b)) generated when the bearing rotates at high speed. Tensile stress f3 (same figure) acts on the inner peripheral portion of the cage 10 (each cage component 20), specifically, in the vicinity of the communication hole 22h (through hole 2h). Even in this case, the residual tensile stress f1 and the tensile stress f3 can be reliably loaded.

  That is, in the cage 10, the distance d2 of the cage structure 20 described above is set to be larger than the distance d1 (d1 <d2 (d2 = d1 × 2 as an example)). The distance between the outer peripheral portion of the retainer 10 and the peripheral portion of the communication hole 22h (the interval between the outer peripheral portion of the cage structure 20 and the peripheral portion of the through hole 2h) is the distance between the inner peripheral portion of the retainer 10 and the peripheral portion of the communication hole 22h. The distance between the inner peripheral portion of the cage structure 20 and the peripheral edge portion of the through hole 2h can be enlarged, and the rigidity of the inner peripheral portion of the cage 10 can be increased by the enlarged region. it can.

  As described above, according to the cage 10 according to the present embodiment, the distance (region) between the peripheral edge portion of the communication hole 22h (through hole 2h) through which the rivet 6 is inserted and the inner peripheral portion of the cage 10 is sufficiently large. By securing, the influence of the residual tensile stress f1 generated when the rivet 6 is crimped on the inner peripheral portion can be minimized, and the tensile stress generated in the inner peripheral portion by the centrifugal force f2 under high-speed rotation. The rigidity with respect to f3 can be increased. Therefore, even in an environment where the rotation is performed at a high speed, it is possible to maintain stable cage rigidity without causing damage (for example, breakage or cracking) to the cage 10 (particularly, the inner periphery) over a long period of time. it can. Thereby, it becomes possible to continue rotating the holder | retainer 10 smoothly with a fixed precision, and it can achieve the lifetime improvement.

  The cage 10 holds a plurality of balls (not shown) one by one at a predetermined interval (for example, an equal interval) so that the balls can rotate freely. By constructing a bearing (not shown) by incorporating it, it becomes possible to continue to rotate the bearing smoothly with a certain accuracy, and it is possible to extend its life.

The perspective view which shows the whole structure of the cage for ball bearings which concerns on one Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the cage structure of the ball bearing retainer which concerns on one Embodiment of this invention, Comprising: (a) is a perspective view which shows the whole structure, (b) is the drilling position of a through-hole. The principal part top view shown. The whole perspective view which shows the structural example of the conventional ball bearing cage. It is a figure for demonstrating the operation | work which unites two cage structure bodies by caulking a rivet, Comprising: (a) is principal part sectional drawing which shows the state before caulking, (b) is caulking. The principal part sectional drawing which shows the state after fastening. It is a figure for demonstrating the load condition with respect to the conventional cage structure, Comprising: (a) is a principal part top view which shows the residual tensile stress at the time of rivet caulking, (b) is the centrifugal force at the time of bearing rotation FIG. 3 is a plan view of a main part showing a tensile stress associated with the centrifugal force, and FIG.

Explanation of symbols

2 Flat part 2h Through hole 4 Concave part 6 Fixing member (rivet)
8 Pocket 10 Ball Bearing Retainer 20 Retainer Constructing Body 22h Communication Hole d1 Shortest Distance between Retainer Constructing Body Outer Periphery and Through Hole Periphery d2 Shortest Distance Between Retainer Constructing Body Peripheral and Through Hole Peripheral

Claims (4)

The ball is incorporated in a ball bearing having at least a pair of bearing rings that are opposed to each other so as to be relatively rotatable and a plurality of balls that roll between the bearing rings, and each of the balls is stored in a pocket arranged at a predetermined interval. And a ball bearing retainer that is rotatably held,
A flat plate-like flat portion having a through-hole through which the fixing member is inserted and a concave portion recessed in a substantially hemispherical shape from the flat portion are alternately connected to form an annular cage structure, and the concave portion With the fixing member inserted into each of the communicated through-holes, the two cage structures are opposed to each other so that they are recessed in opposite directions and the flat portions communicate with each other. The pockets are configured by fixing and integrally combining the substantially spherical concave spaces formed by the opposed concave portions arranged at predetermined intervals in the circumferential direction,
When the shortest distance between the outer peripheral part of the cage structure and the peripheral part of the through hole is d1, and the shortest distance between the inner peripheral part of the cage structure and the peripheral part of the through hole is d2, d1 < A ball bearing retainer characterized in that the relationship d2 is set. The ball is incorporated in a ball bearing having at least a pair of bearing rings that are opposed to each other so as to be relatively rotatable and a plurality of balls that roll between the bearing rings, and each of the balls is stored in a pocket arranged at a predetermined interval. And a ball bearing retainer that is rotatably held,
A flat plate-like flat portion having a through-hole through which the fixing member is inserted and a concave portion recessed in a substantially hemispherical shape from the flat portion are alternately connected to form an annular cage structure, and the concave portion With the fixing member inserted into each of the through-holes communicated with each other, the two cage components are opposed to each other so that they are recessed in opposite directions and the flat portions communicate with each other. The pockets are configured by fixing and integrally combining the substantially spherical concave spaces formed by the opposed concave portions arranged at predetermined intervals in the circumferential direction,
The fixed member after the fixing has an axial center that is concentric with the cage structure and a virtual circumference that is concentric with a diameter that is half the total of the outer diameter and inner diameter of the cage structure. The ball bearing retainer is positioned near the outer periphery of the retainer structure.   A rivet is used as the fixing member, and the two retainer components are integrally combined by inserting the rivet into each of the communicating through holes and caulking one end of the shaft. The ball bearing retainer according to claim 1 or 2, wherein the ball bearing retainer is provided. A ball bearing comprising at least a pair of bearing rings arranged to be relatively rotatable and a plurality of balls that roll between the bearing rings,
Each ball is rotatably held at a predetermined interval by the ball bearing retainer according to any one of claims 1 to 3.

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