JP2020153462A - Bearing attachment structure - Google Patents

Abstract

To facilitate the attachment/detachment of a bearing to/from a rotating shaft, in a bearing attachment structure for fixing a bearing inner ring to the rotating shaft via a tapered sleeve.SOLUTION: A bearing 2 comprises a bearing-side nut 5, a sleeve-side nut 7, and a connecting mechanism 16 for connecting the bearing-side nut 5 and the sleeve-side nut 7. A male screw part 13 corresponding to a female screw part 15 of the bearing-side nut 5 is formed at one end side on an outside diameter face of a bearing inner ring 3, a male screw part 14 corresponding to a female screw part 17 of the sleeve-side nut 7 is formed at one end side on an outside diameter face of a tapered sleeve 4, and the male screw part 14 of the tapered sleeve 4 is protruded from the bearing inner ring 3 so that the bearing-side nut 5 and the sleeve-side nut 7 which are connected to each other are rotated to be screwed onto the male screw part 13 and the male screw part 14 in a state where the bearing inner ring 3 is fit onto the outside of the tapered sleeve 4. A distance in an axial direction between the bearing-side nut 5 and the sleeve-side nut 7 is adjustable in a state that both the nuts are maintained to be connected to each other.SELECTED DRAWING: Figure 1

Description

The present invention relates to a bearing mounting structure for mounting a bearing on a rotating shaft via a tapered sleeve.

Conventionally, as a mounting structure for mounting the inner ring of a bearing on a rotating shaft, a mounting structure using a tapered sleeve (for example, an adapter sleeve) having a cut portion formed therein has been known. In this type of mounting structure, the inner ring of the bearing is rotated by pushing the inner ring of the bearing into the tapered sleeve after fitting the inner ring of the bearing with the tapered inner diameter to the outside of the tapered sleeve having the tapered outer diameter. Fix to the shaft.

In Patent Document 1, an adapter sleeve having a tapered outer peripheral surface and a groove in the longitudinal direction is interposed between the rotating shaft and the inner ring with a tapered hole of the bearing, and the male outer circumference on the small diameter side of the sleeve is interposed. A mounting structure is described in which a fixing ring having a female screw hole on the inner circumference is screwed into a screw portion, and a bearing is mounted and fixed to a rotating shaft by utilizing a wedge action. In this mounting structure, after the fixing ring is screwed, the mounting bolt is screwed into a plurality of female screw small holes formed in the fixing ring, and the tip of the mounting bolt is on the side end surface of the bearing inner ring. By tightening the mounting bolts from the contacted state, the adapter sleeve is further pulled toward the smaller diameter side of the inner ring of the bearing, and the bearing and the rotating shaft are mounted and fixed.

Further, at the side end of the fixing ring, small holes for removal are formed at equal intervals in the circumferential direction, and at the side end of the inner ring of the bearing, a female for removal that can face the small holes for removal. Small screw holes are formed. When removing the bearing, align the position of the small hole for removal with the small hole for removing the inner ring of the bearing, and in this state, screw the bolt for removal from the small hole for removal into the small hole for female screw for removal. Fit and tighten. As a result, the adapter sleeve integrated with the fixing ring is pushed toward the large diameter side of the tapered hole of the bearing inner ring and comes out, so that the rotating shaft and the bearing can be separated.

JP-A-2018-84302

By the way, in the prior art described in Patent Document 1, when removing the bearing from the rotating shaft, it is necessary to align the position of the small hole for removal with the position of the small hole for removal of the inner ring of the bearing. This alignment needs to be performed accurately so that the removal bolt can be screwed into the small hole for the female screw for removal, which is a laborious work.

The present invention has been made in view of such circumstances, and an object of the present invention is to facilitate attachment / detachment of a bearing to a rotating shaft in a bearing mounting structure in which an inner ring of the bearing is fixed to the rotating shaft via a tapered sleeve. To do.

In order to solve the above-mentioned problems, the first invention has a bearing mounting structure in which a bearing inner ring having a tapered inner diameter surface is attached to a rotating shaft via a tapered sleeve having a tapered outer diameter surface. The bearing side nut having the first female threaded portion formed on the inner diameter surface, the sleeve side nut having the second female threaded portion formed on the inner diameter surface, and the bearing side nut and the sleeve side nut are coaxial with each other. A connecting mechanism for connecting is provided, and on the outer diameter surface of the inner ring of the bearing, a first male thread portion corresponding to the first female thread portion is formed on one end side where the inner diameter surface is narrowed, and the outer diameter surface of the tapered sleeve. Then, in a state where the second male threaded portion corresponding to the second female threaded portion is formed on one end side where the outer diameter surface is narrowed and the inner ring of the bearing is fitted to the outside of the tapered sleeve, the second male threaded portion is connected using a connecting mechanism. The tapered sleeve so that the first female threaded portion can be screwed into the first male threaded portion and the second female threaded portion can be screwed into the second male threaded portion by rotating the bearing side nut and the sleeve side nut. Of these, the second male screw portion protrudes from one end of the inner ring of the bearing, and the connecting mechanism is configured so that the axial distance between the nut on the bearing side and the nut on the sleeve side can be adjusted while being connected. It is a mounting structure of the bearing.

In the second invention, in the first invention, the connecting mechanism is formed on a plurality of bolts, a plurality of bolt mounting portions formed on the sleeve side nut and mounted on the head of the bolt, and a bearing side nut. It has a plurality of screw holes into which the threaded portion of the bolt is screwed.

In the third invention, in the second invention, the threaded portion of the bolt is a left-hand thread.

The fourth invention is the second or third invention, in which the bolt mounting portion is a hole that opens in the sleeve side nut on the surface facing the bearing side nut and the outer diameter surface, and the sleeve side nut has a bolt. A wrench insertion hole having a size that allows the head of the bolt to pass through is formed so as to be connected to the mounting hole from the opposite surface of the facing surface.

In the present invention, when the bearing is attached to the rotating shaft, the bearing side nut and the sleeve side nut integrated by the connecting mechanism are rotated together with the bearing inner ring fitted to the outside of the tapered sleeve to provide the bearing. Screw the side nut into the first male thread and the sleeve side nut into the second male thread. Then, by adjusting the connecting mechanism, the bearing side nut and the sleeve side nut are separated in the axial direction, so that the taper sleeve is located on the smaller diameter side in the inner ring of the bearing. As a result, the taper sleeve is further fitted inside the inner ring of the bearing, and the taper sleeve tightens the rotating shaft. As a result, the inner ring (bearing) of the bearing is firmly fixed to the rotating shaft via the tapered sleeve. On the other hand, when the bearing is removed from the rotating shaft, the taper sleeve is located on the large diameter side in the inner ring of the bearing by bringing the nut on the bearing side and the nut on the sleeve side closer to each other in the axial direction by adjusting the connecting mechanism. As a result, the inner ring of the bearing is detached from the tapered sleeve, and the inner ring of the bearing (bearing) is removed from the rotating shaft.

The connecting mechanism is, for example, a mechanism using a plurality of bolts for connecting the bearing side nut and the sleeve side nut. In this case, both when attaching the bearing and when removing the bearing, the adjustment of the connecting mechanism is a simple operation of rotating each bolt. Further, when mounting the bearing, the work of screwing the bearing side nut and the sleeve side nut integrated by the connecting mechanism together is also a relatively simple work. According to the present invention, in the bearing mounting structure in which the inner ring of the bearing is fixed to the rotating shaft via the tapered sleeve, it is possible to easily attach / detach the bearing to / from the rotating shaft.

FIG. 1 is a structural drawing of a bearing according to an embodiment. FIG. 2 is a view of the bearing viewed from the small diameter side of the inner diameter surface of the inner ring of the bearing. FIG. 3 is a perspective view of the adapter sleeve. FIG. 4 is a perspective view of the bearing side nut and the sleeve side nut. FIG. 5 is a diagram for explaining the first half of the bearing mounting method. FIG. 6 is a diagram for explaining the latter half of the bearing mounting method. FIG. 7 is a diagram for explaining a method of removing the bearing.

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 7. The following embodiments are examples of the present invention, and are not intended to limit the scope of the present invention, its applications, or its uses.

[Bearing and bearing mounting structure configuration]
The bearing 2 according to the present embodiment has a mounting structure of a bearing 2 for mounting a bearing inner ring 3 having a tapered inner diameter surface on a rotating shaft 1 via an adapter sleeve 4 having a tapered outer diameter surface. is there. The mounting structure of the bearing 2 is such that the adapter sleeve 4 is attached to the rotating shaft 1 by utilizing the wedge action generated when the adapter sleeve 4 is relatively moved to the smaller diameter side (right side in FIG. 1) on the inner diameter surface of the bearing inner ring 3. And the bearing inner ring 3 is attached.

As shown in FIGS. 1 and 2, the bearing 2 includes a bearing inner ring 3, a bearing outer ring 23 that constitutes a raceway ring together with the bearing inner ring 3, and a plurality of rolling wheels arranged between the bearing outer ring 23 and the bearing inner ring 3. It is equipped with a moving body 10 (roller or ball). Each rolling element 10 is held at a fixed position by a cage (not shown). In FIG. 1, the upper side of the rotating shaft 1 above the center line (dashed line) is a cross-sectional view of the bearing 2, and the lower side of the center line is a side view of the bearing 2. This point is the same for FIGS. 5 to 7.

Further, the mounting structure of the bearing 2 includes the above-mentioned adapter sleeve 4 (see FIG. 3), a bearing side nut 5 (fixing nut) in which a first female screw portion 15 for mounting on the bearing inner ring 3 is formed on the inner diameter surface. A sleeve-side nut 7 (tightening nut) in which a second female screw portion 17 for mounting on the adapter sleeve 4 is formed on the inner diameter surface, and a connecting mechanism for coaxially connecting the bearing-side nut 5 and the sleeve-side nut 7 to each other. It has 16.

Hereinafter, regarding the bearing inner ring 3, the small diameter side of the inner diameter surface is referred to as “one end side”, and the opposite side thereof is referred to as “other end side”. Regarding the adapter sleeve 4, the small diameter side of the outer diameter surface is referred to as "one end side", and the opposite side is referred to as "other end side". Regarding the bearing side nut 5, one end side when mounted on the bearing inner ring 3 is referred to as "outside", and the opposite side is referred to as "inside". Further, regarding the sleeve side nut 7, one end side when it is attached to the adapter sleeve 4 is referred to as "outside", and the opposite side is referred to as "inside".

[Each part such as bearing]
The bearing inner ring 3 is formed in a substantially cylindrical shape. As described above, the inner diameter surface of the bearing inner ring 3 is formed in a tapered shape. In the bearing inner ring 3, a portion forming a raceway ring together with the bearing outer ring 23 is provided on the other end side from the center in the axial direction (left-right direction in FIG. 1) of the bearing 2. Further, on the outer diameter surface of the bearing inner ring 3, the first male screw portion 13 corresponding to the first female screw portion 15 of the bearing side nut 5 is formed on one end side where the inner diameter surface is narrowed. Further, on the outer diameter surface of the bearing inner ring 3, a step is formed on the other end side of the formation region of the first male thread portion 13. The outer diameter of the bearing inner ring 3 is smaller on one end side than the other end side than the step.

As shown in FIG. 3, the adapter sleeve 4 is formed in a substantially cylindrical shape. As described above, the outer diameter surface of the adapter sleeve 4 is formed in a tapered shape. The slope of the taper on the outer diameter surface of the adapter sleeve 4 is substantially equal to the slope of the taper on the inner diameter surface of the bearing inner ring 3. Further, on the outer diameter surface of the adapter sleeve 4, a second male screw portion 14 corresponding to the second female screw portion 17 of the sleeve side nut 7 is formed on one end side where the outer diameter surface is narrowed.

Further, the adapter sleeve 4 is formed with a cut portion 24 extending in the axial direction (axial direction). Therefore, the diameter of the adapter sleeve 4 is reduced when a load is applied from the outer diameter surface toward the axial center. The width of the cut portion 24 is widest in the forming region of the second male threaded portion 14, and there is a narrow section on the other end side of the forming region of the second male threaded portion 14, and the other end side from that section is The width is constant. In the present embodiment, the cut portion 24 is formed between both ends of the adapter sleeve 4, but the cut portion 24 may be a slit hole extending from one end to the front of the other end. In this case, a plurality of cutting portions 24 may be formed.

As shown in FIG. 4, the bearing-side nut 5 and the sleeve-side nut 7 are both ring-shaped members having flat side surfaces and parallel to each other. Comparing the bearing side nut 5 and the sleeve side nut 7, the outer diameter is substantially the same, the inner diameter of the bearing side nut 5 is larger, and the thickness of the sleeve side nut 7 is larger.

Further, the inner diameter of the bearing side nut 5 is substantially equal to the outer diameter of one end portion (formation region of the first male screw portion 13) of the bearing inner ring 3. The above-mentioned first female screw portion 15 is formed on the inner diameter surface of the bearing side nut 5. On the other hand, the inner diameter of the sleeve-side nut 7 is substantially equal to the outer diameter of one end of the adapter sleeve 4 (the region where the second male screw portion 14 is formed). The above-mentioned second female screw portion 17 is formed on the inner diameter surface of the sleeve side nut 7.

The bearing-side nut 5 is formed with a plurality of female screw holes 9 (four female screw holes in the present embodiment) into which the threaded portions of the bolts 6 described later are screwed. Each female screw hole 9 opens on the outer side surface of the bearing side nut 5 and extends in the thickness direction of the bearing side nut 5. The plurality of female screw holes 9 are arranged at equal intervals (equal angle intervals) in the circumferential direction when the bearing side nut 5 is viewed in the axial direction, and the distances from the axial center of the bearing side nut 5 are the same. ..

Further, the sleeve-side nut 7 is formed with a plurality of bolt mounting holes 8 (corresponding to bolt mounting portions) on which the head side of the bolt 6 described later is mounted. Each bolt mounting hole 8 is a hole that opens in the sleeve side nut 7 on the facing surface (inner side surface) and the outer diameter surface of the bearing side nut 5, and the bolt 6 can be inserted from the outer diameter surface side. The same number of bolt mounting holes 8 as the female screw holes 9 are formed. The plurality of bolt mounting holes 8 are arranged at equal intervals like the female screw holes 9, and the distances from the axis of the sleeve side nut 7 are the same as each other. The plurality of bolt mounting holes 8 are arranged at positions where the bearing side nut 5 and the sleeve side nut 7 are arranged coaxially and overlap with the plurality of female screw holes 9 when viewed in the axial direction.

Each bolt mounting hole 8 will be specifically described. When viewed from the outer diameter side, each bolt mounting hole 8 has a fitting portion 8a into which the head of the bolt 6 is fitted and a fitting portion 8a from the head, as shown in the enlarged view surrounded by wavy lines in FIG. It is composed of an insertion portion 8b through which an extending screw portion is inserted. The insertion portion 8b extends from the fitting portion 8a to the inner side surface, and is narrower than the fitting portion 8a. Further, the sleeve side nut 7 is formed with a wrench insertion hole 11 for each bolt mounting hole 8 which is connected to the bolt mounting hole 8 from the opposite surface (outer side surface) of the above-mentioned facing surface. The wrench insertion hole 11 is formed in the partition wall 7a that partitions the outside of the fitting portion 8a in the sleeve side nut 7. The head of the bolt 6 mounted in each bolt mounting hole 8 cannot pass through the insertion portion 8b or the wrench insertion hole 11 in the sleeve side nut 7, and the movement of the sleeve side nut 7 in the thickness direction is restricted.

In the present embodiment, the connecting mechanism 16 is composed of a plurality of bolts 6, a plurality of female screw holes 9, and a plurality of bolt mounting holes 8. The connecting mechanism 16 is configured so that the axial distance between the bearing side nut 5 and the sleeve side nut 7 can be adjusted in both directions while the bearing side nut 5 and the sleeve side nut 7 are connected by rotating a plurality of bolts 6. Since a general-purpose product can be used for each bolt 6, a plurality of bolts 6 are used for adjusting the connecting mechanism 16, but need not be considered as a part of the connecting mechanism 16.

[Bearing mounting method]
A method of attaching the bearing 2 to the rotating shaft 1 will be described with reference to FIGS. 5 and 6.

First, the rotating shaft 1 is inserted inside the adapter sleeve 4, and as shown in FIG. 5A, the bearing inner ring 3 is further fitted on the outside of the adapter sleeve 4. When fitting the bearing inner ring 3 to the outside of the adapter sleeve 4, the bearing inner ring 3 is inserted from one end side of the adapter sleeve 4 so that the tapered surfaces are in the same direction. In the state where the bearing inner ring 3 is fitted to the outside of the adapter sleeve 4, the second male screw portion 14 of the adapter sleeve 4 projects from one end of the bearing inner ring 3.

Next, as shown in FIG. 5B, the bearing side nut 5 and the sleeve side nut 7 are connected by a plurality of bolts 6. In this connection, the bolt 6 is mounted in each bolt mounting hole 8, and the bearing side nut 5 and the sleeve side nut 7 are overlapped so that the female screw holes 9 and the bolt mounting holes 8 face each other. This is done by screwing the bolt 6 into the female screw hole 9. Each bolt 6 is screwed into each female screw hole 9 until the bearing side nut 5 and the sleeve side nut 7 are close to each other or come into contact with each other. Since the threaded portion of each bolt 6 is a left-hand thread, each bolt 6 is rotated counterclockwise.

Next, as shown in FIG. 6A, the bearing side nut 5 and the sleeve side nut 7 connected by the plurality of bolts 6 are rotated together, and the first female screw portion 15 is changed to the first male screw portion 13. The second female screw portion 17 is screwed into the second male screw portion 14. This screwing is performed until the bearing side nut 5 comes into contact with or approaches the stepped surface of the bearing inner ring 3. The second male threaded portion 14 of the adapter sleeve 4 becomes higher as the thread approaches the other end side (left side in FIG. 6A). Therefore, when the sleeve side nut 7 is screwed into the second male threaded portion 14, The second male screw portion 14 of the adapter sleeve 4 is pressed inward.

Next, each bolt 6 is rotated clockwise. Then, each bolt 6 comes out of the female screw hole 9. At this time, the head of each bolt 6 cannot pass through the wrench insertion hole 11 of the sleeve-side nut 7, and is caught by the partition wall 7a in which the wrench insertion hole 11 is formed. Therefore, each bolt 6 does not move with respect to the sleeve side nut 7, but the bearing side nut 5 and the bearing inner ring 3 move to the other end side as shown in FIG. 6B, and the bearing side nut 5 becomes the sleeve. Separate from the side nut 7. In the inner ring 3 of the bearing, the adapter sleeve 4 is located on the smaller diameter side. As a result, the adapter sleeve 4 is further fitted inside the bearing inner ring 3, and the adapter sleeve 4 tightens the rotating shaft 1. As a result, the bearing inner ring 3 (bearing 2) is firmly fixed to the rotating shaft 1 via the adapter sleeve 4.

[Bearing removal method]
A method of removing the bearing 2 from the rotating shaft 1 will be described with reference to FIG. 7.

When removing the bearing 2 from the rotating shaft 1, each bolt 6 is rotated counterclockwise. Then, each bolt 6 enters the female screw hole 9. At this time, the head of each bolt 6 cannot pass through the insertion portion 8b of the sleeve side nut 7 and is caught by the forming wall of the insertion portion 8b. Therefore, each bolt 6 does not move with respect to the sleeve side nut 7, but the bearing side nut 5 and the bearing inner ring 3 move to one end side, and the bearing side nut 5 moves to the sleeve side nut 7 as shown in FIG. Get closer to. In the inner ring 3 of the bearing, the adapter sleeve 4 is located on the large diameter side. As a result, the bearing inner ring 3 is detached from the adapter sleeve 4, and the adapter sleeve 4 is also detached from the rotating shaft 1.
[Effects of the embodiment, etc.]

In the present embodiment, both the adjustment of the connecting mechanism 16 when attaching the bearing 2 and the adjustment of the connecting mechanism 16 when removing the bearing 2 are simple operations of turning each bolt 6. Further, when the bearing 2 is attached, the work of screwing the bearing side nut 5 and the sleeve side nut 7 integrated by the connecting mechanism 16 together is also a relatively simple work. According to this embodiment, it is possible to easily attach / detach the bearing 2 to / from the rotating shaft 1.

In this embodiment, the threaded portion of the bolt 6 is a left-hand thread. Here, in the connecting mechanism 16 using a plurality of bolts 6, when the bolts 6 are rotated clockwise so as to come out from the female screw holes 9 of the bearing side nut 5, the bearing inner ring 3 (bearing 2) becomes as described above. It is firmly fixed to the rotating shaft 1 via the adapter sleeve 4. That is, the rotation direction of the bolt 6 when firmly fixing the bearing inner ring 3 is the same as the rotation direction of the right-hand screw when performing normal fastening. Therefore, the operator can intuitively attach / detach the bearing 2.

In this embodiment, the adapter sleeve 4 shown in FIG. 3 is a general-purpose product. Here, since the cut portion 24 of the adapter sleeve 4 is formed from one end to the other end, when the adapter sleeve 4 moves relatively toward the smaller diameter side in the bearing inner ring 3, the rotation shaft 1 is substantially uniformly in the length direction. Tighten. Therefore, the rotating shaft 1 can be stably supported as compared with the adapter sleeve having the uncut portion as described in Patent Document 1. However, since the adapter sleeve 4 adheres to the rotating shaft 1 substantially uniformly from one end to the other end, the adapter sleeve 4 cannot be easily removed after being used for a certain period of time. In the present embodiment, even such an adapter sleeve 4 can be easily removed by bringing the sleeve-side nut 7 close to the bearing-side nut 5.

In the present embodiment, by rotating the bolt 6 with a relatively small force, the rotation shaft 1 can be evenly tightened in the circumferential direction by the adapter sleeve 4. Therefore, the deviation of the axial center between the rotating shaft 1 and the bearing 2 at the completion of mounting the bearing 2 can be reduced. In addition, the adapter sleeve 4 can reduce scratches on the outer peripheral surface of the rotating shaft 1 when the rotating shaft 1 is tightened.

[Other Embodiments]
In the above-described embodiment, the mounting structure of the bearing 2 is shown as an example of using the spherical roller bearing, but it may be described as another bearing. Further, the bearing 2 is a double-row bearing in which a plurality of rows of rolling elements 10 are provided, but it may be a single-row bearing.

In the above embodiment, the threaded portion of the bolt 6 may be a right-hand thread.

The present invention can be applied to a bearing mounting structure or the like in which a bearing is mounted on a rotating shaft via a tapered sleeve.

1 Rotating shaft 2 Bearing 3 Bearing inner ring 4 Adapter sleeve (taper sleeve)
5 Bearing side nut 6 Bolt 7 Sleeve side nut 8 Bolt mounting hole (bolt mounting part)
9 Female screw hole (screw hole)
10 Rolling element 11 Wrench insertion hole

Claims (4)

It is a bearing mounting structure for mounting the inner ring of a bearing having a tapered inner diameter surface to a rotating shaft via a tapered sleeve having a tapered outer diameter surface.
Bearing-side nut with the first female thread on the inner diameter surface,
A sleeve-side nut with a second female thread formed on the inner diameter surface,
A connecting mechanism for coaxially connecting the bearing-side nut and the sleeve-side nut to each other is provided.
On the outer diameter surface of the inner ring of the bearing, a first male screw portion corresponding to the first female screw portion is formed on one end side where the inner diameter surface is narrowed.
On the outer diameter surface of the tapered sleeve, a second male thread portion corresponding to the second female thread portion is formed on one end side where the outer diameter surface is narrowed.
In a state where the inner ring of the bearing is fitted to the outside of the tapered sleeve, the nut on the bearing side and the nut on the sleeve side, which are connected by using the connecting mechanism, are rotated to make the first female screw portion into the first female screw portion. The second male threaded portion of the tapered sleeve projects from one end of the bearing inner ring so that the male threaded portion can be screwed into the second female threaded portion.
The connecting mechanism is a bearing mounting structure in which the bearing-side nut and the sleeve-side nut are connected and the distance between them in the axial direction can be adjusted. In the connecting mechanism, a plurality of bolts, a plurality of bolt mounting portions formed on the sleeve-side nut to mount the head of the bolt, and a screw portion of the bolt formed on the bearing-side nut are screwed together. The mounting structure for a bearing according to claim 1, further comprising a plurality of screw holes. The bearing mounting structure according to claim 2, wherein the threaded portion of the bolt is a left-hand thread. The bolt mounting portion is a hole that opens in the sleeve-side nut on the surface facing the bearing-side nut and the outer diameter surface.
The second or third aspect of the present invention, wherein the sleeve-side nut is connected to the bolt mounting hole from the opposite surface of the facing surface, and is formed with a wrench insertion hole having a size so that the head of the bolt cannot pass through. Bearing mounting structure.

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