JP5880262B2 - Double nut fastening structure and power generator - Google Patents

Description

  The present invention relates to a double nut fastening structure for fixing a rolling bearing that supports a main shaft or the like of a wind power generator and a power generator.

  As what fixes the rolling bearing which supports the main axis | shaft of a wind power generator, what is shown, for example in patent document 1 is known. In Patent Document 1, a nut is screwed into a male thread portion formed at one end portion of a main shaft, and the end surface of the nut is brought into contact with the inner ring end surface of the rolling bearing, thereby restricting axial movement of the rolling bearing. Yes.

JP 2012-39850 A (see FIG. 3)

By the way, since the rolling bearing that supports the main shaft of the wind turbine generator has a large outer diameter exceeding 2 m, the nut for fixing the large rolling bearing has a large outer diameter exceeding 1 m. Things are used. In addition, when the nut is actually attached to the main shaft, the work place is restricted due to the structure of the wind power generator, and therefore, a large nut must be tightened manually. For this reason, in a wind power generator, the nut which fixes a rolling bearing cannot be tightened strongly, but there existed a problem that a nut loosened. As a nut for preventing such loosening, it is conceivable to use a double nut. However, in this case as well, it is necessary to tighten each nut manually.
This invention is made | formed in view of such a situation, and it aims at providing the double nut fastening structure and electric power generating apparatus which can be fastened with an appropriate fastening torque also by human power.

  The double nut fastening structure of the present invention includes a first nut and a second nut that are screwed to each other adjacent to a screw shaft, and the axial ends of the nuts facing each other are pressed together. A double nut fastening structure in which both nuts are fastened, wherein a first flange is formed to project outward in the axial direction at the axial end of the first nut, and the second nut A second collar portion that radially opposes the first collar portion is formed at the axial end portion so as to protrude outward in the axial direction, and the first collar portion includes the second collar portion on the radially outer side of the screw shaft. A through hole penetrating in the opposing direction of the first collar part and the second collar part is formed, and a screw hole is formed in the second collar part at a position opposed to the through hole, and penetrates the through hole. The axial end portion by a screw bolt that is screwed into the screw hole Wherein the Judges are tightened the two nuts in the direction to be pressed against each other.

  According to the present invention, the screw bolt is passed through the first flange portion in a state where the first flange portion formed on the first nut and the second flange portion formed on the second nut are opposed to each other in the radial direction. By passing through the hole and screwing into the screw hole of the second flange portion, the nuts can be tightened in a direction in which the axial end portions of the nuts facing each other are pressed against each other. Thereby, even if both nuts are not directly tightened, both nuts can be tightened with an appropriate tightening torque by manually tightening the screw bolts.

In the double nut fastening structure, a third flange portion is formed on the axial end portion of the first nut so as to protrude outward in the axial direction at a position different from the first flange portion in the circumferential direction, and the second nut In the axial direction end portion, a fourth flange portion radially opposite to the third flange portion is formed at a position different from the second flange portion in the circumferential direction, and protrudes outward in the axial direction. One of the flanges and the fourth flange is formed with a screw hole extending in a direction opposite to the one flange and the other flange on the radially outer side of the screw shaft. With a pressing bolt screwed into the threaded hole of the flange portion, the tip end portion is pressed against the other flange portion in the radial direction, and the nuts are further moved in a direction in which the axial end portions are pressed against each other. It is preferable to tighten.
In this case, in a state where the third flange portion formed on the first nut and the fourth flange portion formed on the second nut are opposed to each other in the radial direction, the first flange portion is formed on one of the both flange portions. The screw bolt is screwed into the screw hole, and the tip end portion is pressed against the other flange portion in the radial direction, so that the opposite axial end portions of the nuts are pressed against each other. The nut can be tightened further. Thereby, both nuts can be tightened more strongly by human power by using a screwing bolt and a pressing bolt together.

  The power generation device of the present invention from another viewpoint includes a main shaft that rotates by an external force, a rolling bearing that supports the main shaft, a double nut fastening structure according to claim 1 or 2 that fixes the rolling bearing, and the main shaft. And a generator that generates electric power by rotating the motor. According to this invention, there exists an effect similar to the double nut fastening structure mentioned above.

  According to the double nut fastening structure and the power generator of the present invention, it is possible to fasten with an appropriate tightening torque even by human power.

It is a schematic sectional side view which shows the wind power generator provided with the double nut fastening structure which concerns on one Embodiment of this invention. (A) is a side view which shows one side of the said double nut fastening structure, (b) is a side view which shows the state which decomposed | disassembled the said double nut fastening structure. (A) is AA arrow sectional drawing of Fig.2 (a), (b) is BB arrow sectional drawing of Fig.2 (a). It is a side view which shows the other side surface of the said double nut fastening structure.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic cross-sectional side view showing a wind turbine generator having a double nut fastening structure according to an embodiment of the present invention. This wind power generator (power generator) 1 includes a main shaft 2 that rotates by receiving wind force (external force), a rolling bearing 3 that supports the main shaft 2, a double nut fastening structure 4 that fixes the rolling bearing 3, and a main shaft 2. And a generator 5 that generates electric power by rotation.

For example, a blade (not shown) is connected to one end of the main shaft 2 so as to be integrally rotatable. The blade rotates together with the main shaft 2 when receiving wind force. The other end of the main shaft 2 is connected to a drive shaft (not shown) of the generator 5 via a speed increaser (not shown). Further, on one end portion side of the main shaft 2, a male screw portion (screw shaft) 2 a into which a first nut 11 and a second nut 21 described later are screwed is formed.
The rolling bearing 3 is composed of, for example, a large ball bearing having an outer diameter of about 2 m, an inner ring 3a that is externally fitted and fixed to the stepped portion 2b of the main shaft 2, an outer ring 3b that is fixed to the housing 6, and an inner ring 3a. A plurality of balls (rolling elements) 3c arranged to be able to roll between the outer ring 3b.

  The double nut fastening structure 4 includes a first nut 11 and a second nut 21 that are screwed into the male screw portion 2a of the main shaft 2 adjacent to each other. Both nuts 11 and 21 are large ones whose outer diameter exceeds about 1 m, and screw holes 11a and 21a to be screwed into the male threaded portion 2a are formed on the inner circumferences of both nuts 11 and 21, respectively. ing. The first nut 11 restricts the movement of the inner ring 3 a in the axial direction by bringing its end face into contact with the end face of the inner ring 3 a of the rolling bearing 3.

  FIG. 2A is a side view showing one side surface of the double nut fastening structure 4, and FIG. 2B is a side view showing a state in which the double nut fastening structure 4 is disassembled. 3A is a cross-sectional view taken along the line AA in FIG. 2A, and FIG. 3B is a cross-sectional view taken along the line BB in FIG. 2A. 2B and 3A, the first nut 11 includes a nut body 12 whose outer shape is a regular hexagonal shape, and an axially outer side in a circumferential half of the axial end of the nut body 12 (see FIG. 2 (b) on the left side). The nut body 12 has the screw hole 11a formed on the inner periphery thereof.

  In FIG. 3 (a), a concave arcuate surface 13b is formed in the central portion on the radially inner side of the projecting body 13 and has a diameter larger than the diameter of the screw hole 11a. Further, the protrusion 13 is formed with a first flange portion 14 and a third flange portion 15 that protrude outward in the radial direction with an angular difference of 180 degrees in the circumferential direction. The first flange portion 14 is formed with a through hole 14a that penetrates in the opposing direction between the first flange portion 14 and the second flange portion 24 (described later) on the radially outer side of the male screw portion 2a. The third flange 15 is formed with a pressed surface 15a to which a pressing bolt 32 described later is pressed on the inner side in the radial direction.

  2B and 3B, the second nut 21 includes a nut main body 22 whose outer shape is a regular hexagonal shape, and an axially outer side in a circumferential half of the axial end of the nut main body 22 (see FIG. 2B). 2 (b) on the right side). The nut body 22 has the screw hole 21a formed on the inner periphery thereof. As shown in FIG. 3 (b), a concave arcuate surface 23b is formed in the central portion on the radially inner side of the projecting body 23. The concave arc surface 23b is larger than the diameter of the screw hole 21a.

  In FIG.3 (b), the 2nd collar part 24 and the 4th collar part 25 which each protrude in the radial direction outer side with an angle difference of 180 degree | times to the circumferential direction are formed in the protrusion 23. As shown in FIG. A screw hole 24a penetrating in the facing direction is formed in the second flange portion 24 at a position facing the through hole 14a of the first flange portion 14 on the radially outer side of the male screw portion 2a. In addition, the second flange 24 is disposed to face the first flange 14 in the radial direction in a state where both nuts 11 and 21 are screwed adjacent to each other, and the shaft center of the screw hole 24a. The axial center of the through hole 14a coincides. The fourth flange 25 is arranged to face the third flange 15 in the radial direction in a state where both nuts 11 and 21 are screwed adjacent to each other. Further, the fourth flange portion 25 is formed with a screw hole 25a penetrating in the opposite direction of the third flange portion 15 and the fourth flange portion 25 on the radially outer side of the male screw portion 2a.

  2A and 2B, the axial end surface 22 a of the nut body 22 is in the axial end surface 13 a of the projecting body 13 in a state where the second nut 21 is screwed adjacent to the first nut 11. The axial end surface 23a of the projecting body 23 is in contact with the axial end surface 12a of the nut body 12. Thereby, as shown by arrows a and b in FIG. 2 (a), by tightening the nuts 11 and 12 in the direction in which the axial ends of the nuts 11 and 12 facing each other are pressed together, Both nuts 11 and 12 can be prevented from loosening.

  In FIG. 3A, the double nut fastening structure 4 further includes a screw bolt 31 and a pressing bolt 32 that fasten both nuts 11 and 12. The screw bolt 31 is formed of a small M20 bolt, for example, and penetrates the through hole 14a of the first flange 14 with the first flange 14 and the second flange 24 opposed in the radial direction. It is screwed into the screw hole 24a of the second flange 24. When the screw bolt 31 is manually tightened using a general-purpose tool such as a wrench, the axial force (about 1 t) causes the first flange portion 14 and the second flange portion 24, as indicated by arrows c and d, Approach each other in the radial direction. As a result, the nuts 11 and 21 are tightened in the direction in which the axial ends facing each other are pressed together as described above.

  FIG. 4 is a side view showing the other side surface of the double nut fastening structure 4. 3A and 4, the pressing bolt 32 is a small bolt of M20, for example, like the screw bolt 31, and the third flange portion 15 and the fourth flange portion 25 are opposed to each other in the radial direction. In this state, it is screwed into the screw hole 25a of the fourth flange 25, and the tip 32a presses the pressed surface 15a of the third flange 15 in the radial direction. When the pressing bolt 32 is manually tightened using a general-purpose tool such as a wrench, the axial force (about 1 t) causes the third flange portion 15 and the fourth flange portion 25 to be Are separated from each other in the radial direction. As a result, the nuts 11 and 21 are tightened in the direction in which the axial ends facing each other are pressed together as described above.

  According to the double nut fastening structure 4 configured as described above, the first flange portion 14 formed on the first nut 11 and the second flange portion 24 formed on the second nut 21 are opposed to each other in the radial direction. In this state, the screw bolt 31 passes through the through hole 14a of the first flange 14 and is screwed into the screw hole 24a of the second flange 24, so that the nuts 11 and 21 face each other in the axial direction opposite to each other. Both nuts 11 and 21 can be tightened in a direction in which the parts are pressed against each other. Thereby, even if both nuts 11 and 21 are not directly tightened, both nuts 11 and 21 can be tightened with an appropriate tightening torque by manually tightening the screw bolt 31. In particular, the double nut fastening structure 4 of the present invention is effective when the large nuts 11 and 21 are used in the double nut fastening structure 4 and the place where the fastening work is performed is restricted as in the wind power generator 1. It is.

  Further, the pressing bolt 32 of the fourth flange portion 25 is set in a state where the third flange portion 15 formed on the first nut 11 and the fourth flange portion 25 formed on the second nut 21 are opposed to each other in the radial direction. By screwing into the screw hole 25a and pressing the distal end portion 32a against the third flange 15 in the radial direction, the axial end portions of the nuts 11 and 21 facing each other are pressed together, Both nuts 11 and 21 can be further tightened. Thereby, by using together the screwing bolt 31 and the pressing bolt 32, both the nuts 11 and 21 can be further tightened by human power.

The present invention is not limited to the above-described embodiment, and can be implemented with appropriate modifications. For example, in this embodiment, the screw bolt 31 and the pressing bolt 32 are used to tighten both the nuts 11 and 12, but at least the screw bolt 31 may be used. In this case, at least the first flange portion 14 and the second flange portion 24 may be formed on both the nuts 11 and 12.
Moreover, in this embodiment, the nut arrange | positioned at the right side of Fig.2 (a) is made into the 1st nut 11, and the nut arrange | positioned at the left side is made into the 2nd nut 21, However, Both nuts 11 and 21 are arrange | positioned. Right and left may be reversed. In this case, the 1st collar part 14 and the 3rd collar part 15 should just be formed in the left nut, and the 3rd collar part 15 and the 4th collar part 25 should just be formed in the right nut.

Furthermore, in this embodiment, the screw hole 25a is formed in the 4th collar part 25, but it replaces with this and a screw hole is formed in the 3rd collar part 15, and the pressing volt | bolt 32 is screwed together in this screw hole. The tip of the lever may be pressed against the fourth flange 25 in the radial direction.
In the present embodiment, the third flange portion 15 and the fourth flange portion 25 are formed with an angular difference of 180 degrees in the circumferential direction with respect to the first flange portion 14 and the second flange portion 24. The angle difference can be set to an arbitrary angle.

  Moreover, although the rolling bearing 3 of the present embodiment is a ball bearing, other rolling bearings such as a roller bearing may be applied. Moreover, although the power generation apparatus of this embodiment was illustrated about the case where wind power is used as external force, it is applicable also to the power generation apparatus which generate | occur | produces using other external forces, such as a hydraulic power and a thermal power. Moreover, the double nut fastening structure of the present invention can be applied to devices other than the power generator.

  1: wind power generator (power generator), 2: main shaft, 2a: male screw portion (screw shaft), 3: rolling bearing, 4: double nut fastening structure, 5: generator, 11: first nut, 14: first 14a: through hole, 15: 3rd flange, 21: 2nd nut, 24: 2nd flange, 24a: screw hole, 25: 4th flange, 25a: screw hole, 31: screw bolt 32: Pressing bolt 32a: Tip

Claims (3)

The nut includes a first nut and a second nut that are screwed adjacent to each other, and the nuts are tightened in such a direction that the axial ends of the nuts facing each other are pressed together. A double nut fastening structure,
A first flange is formed on the axial end of the first nut so as to protrude outward in the axial direction.
A second flange portion radially opposite to the first flange portion is formed at the axial end portion of the second nut so as to protrude outward in the axial direction.
A through-hole penetrating in the opposing direction of the first collar part and the second collar part is formed in the first collar part on the radially outer side of the screw shaft,
A screw hole is formed in the second flange part at a position facing the through hole,
The double nut fastening structure is characterized in that the nuts are tightened in a direction in which the axial end portions are pressed against each other by a screw bolt passing through the through hole and screwed into the screw hole. At the axial end portion of the first nut, a third flange portion is formed to protrude outward in the axial direction at a position different from the first flange portion in the circumferential direction,
At the axial end portion of the second nut, a fourth flange portion that is radially opposite to the third flange portion is formed to protrude outward in the axial direction at a position different from the second flange portion in the circumferential direction. ,
A screw hole extending in a facing direction between the one collar part and the other collar part is formed in one collar part of the third collar part and the fourth collar part on the radially outer side of the screw shaft,
With a pressing bolt screwed into the screw hole of the one flange part, the tip end part is pressed against the other flange part in the radial direction, and the axial end parts are pressed against each other. The double nut fastening structure according to claim 1, wherein the nut is further tightened. A spindle that rotates by external force;
A rolling bearing for supporting the main shaft;
The double nut fastening structure according to claim 1 or 2, which fixes the rolling bearing;
And a generator for generating electricity by rotating the main shaft.

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