JP2019132412A - Balance weight and rotary shaft with balance weight - Google Patents

Abstract

To provide a balance weight which can ease stress concentrating on a fixing part with a rotary shaft, and to provide a rotary shaft with the balance weight which achieves improvement of a product life.SOLUTION: A balance weight 10 is fixed to an outer surface F of a rotary shaft 110. The balance weight 10 has: two segments 11 which are disposed at a spacing from each other and have mating surfaces 13a fixable to the rotary shaft 110; and at least one connection part C which connects the two segments 11. The connection part C protrudes outward further than the mating surfaces 13a of the segments 11 in an arch form.SELECTED DRAWING: Figure 2B

Description

  The present invention relates to a balance weight and a rotary shaft with a balance weight.

  Some conventional balance weights are provided with two cuts (cutting grooves) in the balance weight except for the center portion of the balance weight, and leave the center portion as a connecting portion (see, for example, Patent Document 1). . In the balance weight of Patent Document 1, the welded portion with the rotating shaft is provided in two segments connected by the connecting portion. Thereby, in the balance weight of the said patent document 1, the shear force which arises between two welding parts is absorbed in the said connection part, and the fracture | rupture of the said welding part is prevented. Further, some conventional balance weights have holes formed between welded portions (joint portions) of the balance weight (see, for example, Patent Document 2). Thereby, in the balance weight of the above-mentioned patent document 2, since the gap between two welds is cut off by the hole, the rigidity against torsion is reduced and the torsional fatigue life is improved.

Japanese Utility Model Publication No. 4-71842 JP 2005-214335 A

  However, even when the balance weights described in Patent Documents 1 and 2 are fixed to the rotating shaft, stress due to twisting or the like may concentrate on the fixing portion such as the welded portion. This affects the product life of the rotating shaft with balance weight.

  The objective of this invention is providing the balance weight which can relieve | moderate the stress concentrated on the fixing | fixed part with a rotating shaft. Another object of the present invention is to provide a rotating shaft with a balance weight that has an improved product life.

The balance weight according to the present invention is a balance weight fixed to the outer surface of the rotating shaft, and is disposed at a distance from each other, and has two segments having a mating surface that can be fixed to the rotating shaft; And at least one connecting portion that connects the two segments, and the at least one connecting portion is a connecting portion that protrudes in an arch shape outside the mating surface of the segments.
According to the balance weight according to the present invention, since the connecting portion protrudes in an arch shape, the area of the connecting portion becomes a wide movable range, thereby relieving stress concentrated on the fixing portion with the rotating shaft. be able to.

The balance weight which concerns on this invention WHEREIN: The said segment shall have a protrusion part protruded with the said at least 1 connection part so that the said arch-shaped part may be formed.
In this case, by increasing the movable range, it is possible to further relax the stress concentrated on the fixed portion with the rotating shaft.

In the balance weight according to the present invention, the at least one connecting portion may define a gap together with the two segments, and the gap may be a cut.
In this case, the stress concentrated on the fixed portion with the rotating shaft can be further relaxed by making the connecting portion easy to move with one connecting portion as a main movable range.

In the balance weight according to the present invention, the cuts may be arranged at two positions sandwiching the connecting portion.
In this case, the concentration of the stress can be alleviated while distributing the stress concentrated on the plurality of fixed portions in a well-balanced manner with respect to each of the fixed portions using one connecting portion as a main movable range.

In the balance weight according to the present invention, the contour shape on the front end side of the cut may be a semicircular shape in plan view.
In this case, the stress concentration between the connecting portion and the notch can be relaxed.

In the balance weight according to the present invention, the contour shape on the distal end side of the cut may be circular in plan view.
In this case, the stress concentration between the connecting portion and the notch can be relaxed.

In the balance weight according to the present invention, the at least one connecting portion is two connecting portions, the two connecting portions define a gap together with the two segments, and the gap can be a hole. .
In this case, it is possible to relieve the stress concentrated on the fixed portion with the rotary shaft while sufficiently securing the balance weight.

In the balance weight according to the present invention, the hole may be a long hole.
In this case, stress concentration on the connecting portion can be relaxed.

In the balance weight according to the present invention, the segment may have a projection for welding on the mating surface of the segment.
In this case, it is possible to relieve the stress concentrated on the fixed portion with the rotating shaft while ensuring a large degree of freedom in selecting the position for welding.

In the balance weight according to the present invention, the segment may have an overhang portion for welding formed by projecting a part of the outline of the segment in plan view.
In this case, the welding width is limited to be short by projecting a part of the outline of the segment to form a welded portion. For this reason, in the state which fixed the balance weight with respect to the rotating shaft, the restraining force of the rotating shaft with respect to the said balance weight becomes weak. Thereby, the stress which concentrates on a fixed part with a rotating shaft can further be relieved.

In the balance weight according to the present invention, the segment may be a plate-shaped segment.
In this case, the balance weight can be easily manufactured as an integral object.

The rotating shaft with balance weight according to the present invention includes the rotating shaft and the balance weight according to any one of the above, which is fixed to the outer surface of the rotating shaft.
According to the rotating shaft with balance weight according to the present invention, the product life can be improved by relaxing the stress concentrated on the fixed portion between the balance weight and the rotating shaft.

  ADVANTAGE OF THE INVENTION According to this invention, the balance weight which can relieve | moderate the stress concentrated on the fixing | fixed part with a rotating shaft can be provided. In addition, according to the present invention, it is possible to provide a rotating shaft with a balance weight that has an improved product life.

It is a top view which shows the rotating shaft with a balance weight which concerns on 1st embodiment of this invention to which the balance weight which concerns on 1st embodiment of this invention is applied. It is a top view which shows the principal part of the rotating shaft with a balance weight of FIG. It is a front view which shows FIG. 2A. It is a top view which shows the principal part of the rotating shaft with a balance weight which concerns on 2nd embodiment of this invention which applied the balance weight which concerns on 2nd embodiment of this invention to the rotating shaft of FIG. It is a front view which shows FIG. 3A. It is a top view which shows the principal part of the rotating shaft with a balance weight which concerns on 3rd embodiment of this invention which applied the balance weight which concerns on 3rd embodiment of this invention to the rotating shaft of FIG. It is a front view which shows FIG. 4A. It is a top view which shows the principal part of the rotating shaft with a balance weight which concerns on 4th embodiment of this invention which applied the balance weight which concerns on 4th embodiment of this invention to the rotating shaft of FIG. It is a front view which shows FIG. 5A.

  Hereinafter, various embodiments of the present invention will be described with reference to the drawings.

  In FIG. 1, reference numeral 100 denotes a rotating shaft with a balance weight according to the first embodiment of the present invention, to which the balance weight 10 according to the first embodiment of the present invention is applied. The rotating shaft 100 with a balance weight includes a rotating shaft 110 and a balance weight 10 fixed to the outer surface of the rotating shaft 110. The rotating shaft 110 extends along the axis O. The rotating shaft 110 is rotatable around the axis O. When the rotation shaft 110 is rotated around the axis O, the balance of rotation 10 keeps the rotation balance stable.

  In the present embodiment, the rotating shaft 110 is a propeller shaft that can be employed in a power transmission system of a vehicle. In the present embodiment, the rotating shaft 110 includes a cylindrical shaft main body 111, an end 112 fixed to one end of the shaft main body 111, and an end 113 fixed to the other end of the shaft main body 111. ing. In the present embodiment, the end portions 112 and 113 of the rotary shaft 110 constitute a part of the universal joint. The configuration of the end portions 112 and 113 of the rotating shaft 110 can be appropriately changed according to the method of connecting the rotating shaft 110 in the power transmission system.

  In the present embodiment, as shown in FIG. 1, two balance weights 10 are fixed to one side (in this embodiment, the front side of the drawing) of the shaft body 111 of the rotating shaft 110. The two balance weights 10 are fixed at an interval in the direction of the axis O. In the present embodiment, two balance weights 10 are also fixed to the other side of the shaft main body 111 (in the present embodiment, the back side of the drawing), as in the illustrated one side (not shown). That is, in this embodiment, a total of four balance weights 10 are fixed to the rotating shaft 110.

  A balance weight 10 shown in FIG. 1 is a balance weight according to the first embodiment of the present invention.

  As shown in FIGS. 2A and 2B, the balance weight 10 has two segments 11 that are spaced apart from each other and can be fixed to the rotating shaft 110 (the shaft body 111 in this embodiment). Yes. As shown in FIG. 2B, the segment 11 has an outer surface 12 and an inner surface 13. In the present embodiment, the segment 11 is a plate-like segment having a small thickness between the outer surface 12 and the inner surface 13 as shown in FIG. 2B. In the present embodiment, as shown in FIG. 2A, the segment 11 includes a contour line L1 extending in the longitudinal direction (short direction of the balance weight 10) in a plan view and a short direction perpendicular to the contour line L1. It is formed in a rectangular shape partitioned by a contour line L2 extending in the (longitudinal direction of the balance weight 10).

  In the balance weight 10 according to the present embodiment, as shown in FIG. 2B, the segment 11 has a curved alignment so as to be aligned with the outer surface F of the rotary shaft 110 (the shaft main body 111 in the present embodiment) when viewed in the axial direction. It has a portion 11a. In the mating portion 11 a of the segment 11, the inner surface 13 of the segment 11 is configured by a mating surface 13 a that mates with the outer surface F of the rotating shaft 110. For example, as shown in FIG. 2B, the mating surface 13a of the segment 11 can be made to coincide with the outer surface F of the rotating shaft 110 in a state where the balance weight 10 is fixed to the rotating shaft 110 as viewed in the axial direction.

  The balance weight 10 has at least one connecting portion C that connects the two segments 11. As shown in FIG. 2B, the connecting part C is a connecting part that protrudes in an arch shape outside the mating surface 13 a of each segment 11. Here, the “outer side” is a side from the inner surface 13 of the segment 11 toward the outer surface 12.

  As shown in FIG. 2B, the connecting portion C projects in an arch shape from between the two segments 11, and forms a space S between the rotating shaft 110. Specifically, the inner surface 14 of the connecting portion C is, for example, between the outer surface F of the rotating shaft 110 and the balance weight 10 fixed to the rotating shaft 110 when viewed in the axial direction as shown in FIG. 2B. A space S is formed. That is, in the present invention, “the connecting portion C projecting in an arch shape outside the mating surface 13a of the segment 11” means that the balance weight is in a state where the segment 11 is fixed to the rotary shaft 110 as shown in FIG. 2B. 10 and a connecting portion having a shape in which a space S is formed between the rotating shaft 110 and the rotating shaft 110.

  Furthermore, in the balance weight 10 according to the present embodiment, the segment 11 has a protruding portion 11b that protrudes together with the connecting portion C so as to form a part of the arch shape when viewed in the axial direction, as shown in FIG. 2B. doing.

  The protruding portion 11 b is provided on the connecting portion C side of each segment 11. The protruding portion 11b is connected to the connecting portion C. Accordingly, in this embodiment, the connecting portion C rises from the mating surface 13a of the segment 11 together with the projecting portions 11b of the two segments 11, and projects in an arch shape outward from the mating surface 13a of the segment 11. In other words, in the protruding portion 11b of the segment 11, the inner surface 13 of the segment 11 is constituted by a rising surface 13b that connects the mating surface 13a of the segment 11 and the inner surface 14 of the connecting portion C. As shown in FIG. 2B, for example, the rising surface 13b of the protruding portion 11b of the segment 11 rises from the mating surface 13a of the segment 11 toward the inner surface 14 of the connecting portion C as viewed in the axial direction. For example, as shown in FIG. 2B, the rising surface 13b of the segment 11 forms a space S together with the inner surface 14 of the connecting portion C in a state where the balance weight 10 is fixed to the rotating shaft 110 when viewed in the axial direction. Yes.

  Furthermore, in the balance weight 10 according to the present embodiment, as shown in FIGS. 2A and 2B, the connecting portion C defines a gap G together with the two segments 11, and the gap G is a notch 18. In this way, the connecting part C can be formed by at least one notch 18. The cut 18 extends from the outer surface 12 to the inner surface 13 of each of the two segments 11. In other words, the notch 18 penetrates the balance weight 10.

  In the balance weight 10 according to the present embodiment, the cuts 18 are arranged at two positions with the connecting portion C interposed therebetween as shown in FIG. 2A. As shown in FIG. 2A, the two cuts 18 are arranged on both sides of the balance weight 10 so that the tips 18e of the cuts 18 face each other in plan view. In the present embodiment, the connecting portion C is a connecting portion that is located between the two cuts 18 on the tip 18e side and is narrower than the overall width W10 in the contour line L1 direction of the segment 11. In this case, as shown in FIG. 2A, the connecting portion 15 becomes a connecting portion whose outer edge is contoured by the shape of the two cuts 18 on the front end 18 e side in a plan view. As shown in FIG. 2A, the outer edge of the connecting portion 15 is contoured by two curves approaching each other (a line describing the shape of the notch 18 on the tip 18 e side) in plan view. For this reason, as shown to FIG. 2A, it has a solid | 3D shape that becomes narrow from both sides equally as the width | variety of the said connection part 15 goes to an arch-shaped upper part by planar view.

  Further, in the balance weight 10 according to the present embodiment, the two cuts 18 are arranged at the center position of the balance weight 10 in the direction of the contour line L <b> 2 of the segment 11. However, the two cuts 18 can be arranged at any position of the balance weight 10 in the direction of the contour line L2 of the segment 11. Further, the tips 18e of the two cuts 18 can be arranged at arbitrary positions with the outline L2 of the segment 11 as a base point. The length L of the cut 18 (the length between the tip 18e of the cut 18 and the contour line L2 of the segment 11) L can also be adjusted as appropriate. Furthermore, in the balance weight 10 according to the present embodiment, the length L of the cut 18 is set so that the lengths L of the two cuts 18 are equal. However, the width d, the length L, and the position of the balance weight 10 as a whole can be selected as appropriate. The two cuts 18 extend in the direction along the contour line L1. However, the cut 18 may be oblique to the contour lines L1 and L2 in plan view.

  By the way, in the balance weight 10 according to the present embodiment, the contour shape on the tip 18e side of the cut 18 is a semicircular shape in plan view as shown in FIG. 2A. As shown in FIG. 2A, the cut 18 includes a cut main body 18a extending with the same width d and a cut leading end 18b connected to the cut main body 18a. The contour shape of the cut 18 on the tip 18e side is formed by the contour of the cut tip 18b. In the present embodiment, the contour shape of the cutting tip 18b is a semicircular shape having a radius r = d / 2.

  In the present embodiment, the balance weight 10 is fixed to the outer surface F of the rotating shaft 110 by welding. In the present embodiment, each of the two segments 11 has a welding projection P on the mating surface 13a of the segment 11, as shown in FIG. 2B and the like.

  In the balance weight 10 according to the present embodiment, the projection P is configured integrally with the segment 11. The projection P protrudes from the mating surface 13 a of the segment 11 and can be brought into contact with the outer surface F of the rotating shaft 110. As shown in FIG. 2B, in this embodiment, the balance weight 10 is welded to the rotary shaft 110 by energizing the projection P in a state where the projection P is in contact with the outer surface F of the rotary shaft 110. The That is, the projection P after welding becomes a welded portion (fixed portion) 70 between the balance weight 10 and the rotating shaft 110. Thereby, when the rotating shaft 100 with the balance weight is rotated around the axis O, the balance weight 10 stably maintains the rotation balance.

  The balance weight 10 according to the present embodiment has a connecting portion 15 that connects the two segments 11, and has a relief structure that releases the force transmitted to the balance weight 10. In the present embodiment, as shown in FIG. 2A, the connecting portion 15 is formed with a cut 18 in a plan view. Furthermore, the connection part 15 protrudes in the shape of an arch. According to the balance weight 10 according to the present embodiment, when the force from the rotating shaft 110 is applied relative to the welded portions 70 of the two segments 11, specifically, between the welded portions 70. Even when a twisting force or the like is applied, as shown in FIG. 2B, the area of the connecting portion 15 becomes a large movable range because the connecting portion 15 protrudes in an arch shape. Thereby, the stress which concentrates on the welding part 70 can be relieved.

  Moreover, in the balance weight 10 which concerns on this embodiment, the segment 11 has the protrusion part 11b which protrudes with the connection part C so that a part of said arch shape may be formed. In this case, the stress which concentrates on the welding part 70 with the rotating shaft 110 can be relieve | moderated more by the movable range increasing.

  In the balance weight 10 according to the present embodiment, the connecting portion 15 divides the gap G together with the two segments 11 in a plan view as shown in FIG. 2A, and the gap G is a notch 18. In this case, the stress which concentrates on the welding part 70 can be relieve | moderated more easily by making the one connection part 15 into a main movable range, and the connection part 15 becoming easy to move.

  In particular, in the balance weight 10 according to the present embodiment, the cuts 18 are arranged at two positions with the connecting portion 15 interposed therebetween. In this case, the concentration of the stress can be alleviated while distributing the stress concentrated on the plurality of welded portions 70 in a well-balanced manner with respect to each of the welded portions 70 using one connecting portion 15 as a main movable range. .

  Furthermore, in the balance weight 10 according to the present embodiment, the contour shape on the tip 18e side of the cut 18 is a semicircular shape in plan view as shown in FIG. 2A. In this case, stress concentration between the connecting portion 15 and the notch 18 can be reduced.

  In the balance weight 10 according to this embodiment, the segment 11 has a projection P for welding on the mating surface 13a of the segment 11 as viewed in the axial direction, as shown in FIG. 2B. In this case, the welding part 70 can be arrange | positioned in the arbitrary positions of the segment 11 by planar view. Therefore, it is possible to relieve the stress concentrated on the welded portion 70 while ensuring a large degree of freedom in selecting the position for welding.

  By the way, the balance weight 10 which concerns on this embodiment can also be fixed with respect to the outer surface F of the rotating shaft 110 using another welding method. For example, the balance weight 10 can be fixed to the rotating shaft 110 by welding at least a part of the contour line L1.

  3A and 3B, reference numeral 200 denotes a rotating shaft with a balance weight according to the second embodiment of the present invention. As shown in FIG. 3B, the balance weight-equipped rotating shaft 200 is obtained by welding the balance weight 20 to the outer surface F of the rotating shaft 110 in FIG. The balance weight 20 is a balance weight according to the second embodiment of the present invention. The balance weight 20 is a modification of the balance weight 10. Hereinafter, parts substantially the same as those in FIG. 1, FIG.

  In the balance weight 20 according to the present embodiment, as shown in FIGS. 3A and 3B, the segment 11 has a protruding portion 21 for welding. As illustrated in FIG. 3A, the overhang portion 21 is formed by projecting a part of the contour line L <b> 1 in the plan view of the segment 11. As shown in FIG. 3B, the overhang portion 21 is a weld portion for welding to the outer surface F of the rotating shaft 110. Reference numeral 70 indicates a welded portion after welding.

  As shown in FIG. 3A, the overhanging portion 21 protrudes from the contour line L1 of the segment 11 along the direction in which the contour line L2 of the segment 11 extends in a plan view. In the present embodiment, as illustrated in FIG. 3A, the overhang portion 21 protrudes in a rectangular shape from the outline L1 of the segment 11 in plan view. If the protruding portion 21 is projected in a rectangular shape as in the present embodiment, a wide welding region (welding area) can be secured. In addition, the shape of the overhang | projection part 21 can be selected suitably. For example, the overhang portion 21 can be projected in a curved shape such as a semicircular shape or a dome shape in a plan view.

  In the balance weight 20 according to the present embodiment, an overhang portion 21 is provided in the segment 11, and the overhang portion 21 is a welded portion. In this case, the welding width (fixed width) of the segment 11 is the width W21 of the overhang portion 21 in the contour line L1 direction. The width W21 of the overhang portion 21 is limited to be shorter than the overall width W20 of the segment 11 in the contour line L1 direction. That is, by welding a part of the contour line L1 of the segment 11 to be a welded portion, the welding width is limited to be short. As described above, if the welding width of the segment 11, that is, the welding width of the balance weight 20 is limited to be short, in a state where the balance weight 20 is fixed to the rotating shaft 110, the force from the rotating shaft 110 is reduced to the two segments 11. When applied relative to each welded portion 70, specifically, the binding force of the rotating shaft 110 against the balance weight 20 when a twisting force or the like is applied between the welded portions 70 is weakened. Therefore, according to the balance weight 20 according to the present embodiment, the stress concentrated on the welded portion 70 can be further relaxed.

  Next, in FIGS. 4A and 4B, reference numeral 300 denotes a rotating shaft with a balance weight according to the third embodiment of the present invention. As shown in FIG. 4B, the rotating shaft 300 with balance weight is obtained by welding the balance weight 30 to the outer surface F of the rotating shaft 110 in FIG. The balance weight 30 is a balance weight according to the third embodiment of the present invention. The balance weight 30 is a modification of the balance weight 20. Hereinafter, parts substantially the same as those in FIGS. 1, 2A and B, and FIGS. 3A and B have the same reference numerals, and the description thereof is omitted.

  The balance weight 30 according to the present embodiment also has at least one connecting portion 35 that connects the two segments 11. Moreover, in this embodiment, it has the connection part 35 as escape structure. Similar to the connecting portion 15 according to the first embodiment, the connecting portion 35 is a connecting portion that protrudes in an arch shape outside the mating surface 13a of each segment 11, as shown in FIG. 4B.

  As with the balance weight 20, the balance weight 30 according to the present embodiment also projects in an arch shape from between the two segments 11, and forms a space S between the rotation shaft 110. Specifically, for example, as shown in FIG. 4B, the inner surface 34 of the connecting portion 35 is between the outer surface F of the rotating shaft 110 in a state where the balance weight 30 is welded to the rotating shaft 110 as viewed in the axial direction. A space S is formed.

  Furthermore, also in the balance weight 30 according to the present embodiment, as shown in FIGS. 4A and 4B, the connecting portion 35 divides the gap G together with the two segments 11, and the gap G is the notch 18. That is, also in this embodiment, the relief structure is constituted by a connecting portion 35 formed by at least one cut 18.

  In the balance weight 30 according to the present embodiment, as with the other balance weights 10 and 20, the notches 18 are arranged at two positions with the connecting portion C interposed therebetween as shown in FIG. 4A. That is, in the present embodiment, the connecting portion 35 is a connecting portion having a narrower width than the overall width W30 in the direction of the contour line L1 of the segment 11. Also in this case, as shown in FIG. 4A, the connecting portion 35 is a connecting portion whose outer edge is contoured by the shape of the two cuts 18 on the front end 18e side in a plan view. As shown in FIG. 4A, the outer edge of the connecting portion 35 is contoured by two curves approaching each other (a line describing the shape of the notch 18 on the tip 18 e side) in plan view. For this reason, as shown in FIG. 4A, the connecting portion 35 has a three-dimensional shape such that, in plan view, the width of the connecting portion 16 is uniformly narrowed from both sides as it goes toward the arch-shaped upper portion. . However, the present embodiment is different from the balance weights 10 and 20 in the following points.

  In the balance weight 30 according to the present embodiment, the contour shape of the cut 18 on the tip 18e side is circular in plan view as shown in FIG. 4A. As shown in FIG. 4A, the cut 18 includes a cut main body portion 18a extending in the same width d and a cut front end portion 18c connected to the cut main body portion 18a in plan view. The contour shape of the cut 18 on the tip 18e side is formed by a cut tip 18c. The outline shape of the cutting tip 18c is a circular shape having a radius R larger than d / 2, except for a part on the cutting body 18a side.

  The balance weight 30 according to the present embodiment also has a connecting portion 35 that connects the two segments 11, and has a relief structure that releases the force transmitted to the balance weight 30. Also in this embodiment, as shown in FIG. 4A, the connecting portion 35 divides the gap G together with the two segments 11 in a plan view, and the gap G is a cut 18. Furthermore, the connection part 35 is also a connection part which protrudes in the shape of an arch outside the mating surface 13a of each segment 11. According to the balance weight 30 according to the present embodiment, when the force from the rotating shaft 110 is applied relative to the welded portions 70 of the two segments 11, specifically, between the welded portions 70. Even when a torsional force or the like is applied, as shown in FIG. 4B, the area of the connecting part 16 becomes a large and movable range because the connecting part 16 protrudes in an arch shape. Thereby, the stress which concentrates on the welding part 70 can be relieved.

  In particular, in the balance weight 30 according to the present embodiment, the contour shape of the cut 18 on the tip 18e side is a circular shape in plan view as shown in FIG. 4A. In this case, stress concentration between the connecting portion 35 and the notch 18 can be reduced.

  Next, in FIGS. 5A and 5B, reference numeral 400 denotes a rotating shaft with a balance weight according to the fourth embodiment of the present invention. As shown in FIG. 5B, the balance weight-equipped rotating shaft 400 is obtained by welding the balance weight 40 to the outer surface F of the rotating shaft 110 in FIG. The balance weight 40 is a balance weight according to the fourth embodiment of the present invention. The balance weight 40 is another modification of the balance weight 20. Hereinafter, parts substantially the same as those in FIGS. 1, 2A and B, FIGS. 3A and B, and FIGS. 4A and B have the same reference numerals, and the description thereof is omitted.

  According to the present invention, the number of connecting portions C can be at least one. In the balance weight 40 according to the present embodiment, the connecting portion C is two connecting portions 45 as shown in FIG. 5A. Moreover, in this embodiment, it has the connection part 45 as said escape structure. Like the connection parts 15 and 35 which concern on other embodiment, the connection part 45 is a connection part which protrudes in the arch shape outside the mating surface 13a of each segment 11, as shown to FIG. 5B.

  As shown in FIG. 5B, the balance weight 40 according to the present embodiment also projects in an arch shape from between the two segments 11, and forms a space S between the rotation shaft 110. Specifically, for example, as shown in FIG. 5B, the inner surface 44 of the connecting portion 45 is between the outer surface F of the rotating shaft 110 in a state where the balance weight 40 is welded to the rotating shaft 110 in the axial direction view. A space S is formed.

  Furthermore, in the balance weight 40 according to the present embodiment, as shown in FIGS. 5A and 5B, the two connecting portions 45 partition the gap G together with the two segments 11 in a plan view as shown in FIG. 5A. The gap G is a hole 19. That is, in the present embodiment, the relief structure includes a plurality of connecting portions 45 formed by at least one hole 19. Thus, the plurality of connecting portions 45 can be formed by at least one hole 19. The hole 19 extends from the outer surface 12 to the inner surface 13 of each of the two segments 11. In other words, the hole 19 passes through the balance weight 40.

  In the balance weight 40 according to the present embodiment, as shown in FIG. 5A, the hole 19 is disposed between the two segments 11 in a plan view. In the present embodiment, the balance weight 40 is arranged at the center. In the present embodiment, as shown in FIG. 5A, the balance weight 40 has a main body section that is partitioned by a contour line L3 extending in the lateral direction and a contour line L4 extending in the longitudinal direction in plan view. . As shown in FIG. 5A, the main body is formed in a rectangular shape in plan view. In the present embodiment, the connecting portion 45 is a connecting portion that is positioned between the contour line L4 of the balance weight 40 and the hole 19 and that is narrower than the overall width W40 in the direction of the contour line L3 of the balance weight 40. In this case, the connecting portion 45 is a connecting portion whose outer edge is contoured by the contour line L4 of the balance weight 40 and the shape of the end 19e of the hole 19. As shown in FIG. 5A, the connecting portion 45 has a curved line (in this embodiment, a line drawing the shape of the tip 19e side of the hole 19) and a straight line (in this embodiment, one side) in plan view. The outer edge of the balance weight 40 is contoured by the contour line L4). For this reason, as shown in FIG. 5A, the connecting portion 45 has a three-dimensional shape in a plan view so that the width of the connecting portion 45 is biased toward one side and becomes narrower toward the upper portion of the arch shape. .

  Further, in the balance weight 40 according to the present embodiment, the hole 19 is arranged at the center position of the contour line L4 in the direction of the contour line L4 of the balance weight 40. However, the hole 19 can be arranged at an arbitrary position in the direction of the contour line L4 of the balance weight 40. Each tip 19e of the hole 19 can be arranged at an arbitrary position toward the contour line L4 of the balance weight 40. The length L of the hole 19 (the length between the two tips 19e) L can also be adjusted as appropriate. Furthermore, in the balance weight 40 according to the present embodiment, the hole 19 is line symmetric with respect to a line passing through the center of the contour line L3 of the balance weight 40 and extending along the contour line L4 of the balance weight 40. In other words, the holes 19 are arranged so that the widths of the two connecting portions 45 are equal. The width d and length L of the hole 19 and the position of the balance weight 10 as a whole can be selected as appropriate. The two holes 19 extend in the direction along the contour line L3. However, the hole 19 may be oblique to the contour lines L3 and L4 of the balance weight 40 in plan view.

  In particular, in the present embodiment, the hole 19 is a long hole in plan view as shown in FIG. 5A. More specifically, as shown in FIG. 5A, the hole 19 has a hole main body portion 19a extending with the same width d, and a hole tip portion 19b connected to each side of the hole main body portion 19a. Yes. The contour shape of both ends 19e of the hole 19 is formed by the contour shape of the hole tip portion 19b. In the present embodiment, the contour shape of the hole tip 19b is a semicircular shape with a radius r = d / 2.

  The balance weight 40 according to the present embodiment also has a connecting portion 45 that connects the two segments 11, and has a relief structure that releases the force transmitted to the balance weight 40. The two connecting portions 45 are formed by the holes 19. Furthermore, the connection part 45 is also a connection part which protrudes in the shape of an arch outside the mating surface 13a of each segment 11. Also when the force from the rotating shaft 110 is applied relative to the two welded portions 70 by the balance weight 40 according to the present embodiment, specifically, a twisting force or the like is generated between the welded portions 70. When added, as shown in FIG. 5B, the area of the connecting portion 17 becomes a large movable range by the amount that the connecting portion 17 protrudes in an arch shape. Thereby, the stress which concentrates on the welding part 70 can be relieved.

  In particular, in the balance weight 40 according to the present embodiment, the two connecting portions 45 define the gap G together with the two segments 11, and the gap G is a hole 19. In this case, when the force from the rotating shaft 110 is applied relative to the welded portions 70 of the two segments 11, specifically, when a twisting force or the like is applied between the welded portions 70. The stress concentrated on the welded portion 70 with the rotating shaft 110 can be alleviated while sufficiently ensuring the rigidity of the balance weight 40.

  Furthermore, in the balance weight 40 according to the present embodiment, the hole 19 is a long hole. In this case, the stress concentration on the connecting portion 45 can be relaxed.

  In addition, according to this invention, the shape of the hole 19 is not specifically limited. For example, it can be a polygonal long hole such as an elliptical hole or a rectangular hole. Moreover, the hole 19 can be not a long hole but a regular polygon hole such as a circular hole or a square hole.

  In any of the balance weights 10 to 40 according to the above-described embodiments, the segment 11 is configured by a plate-like segment. In this case, the balance weights 10 to 40 can be easily manufactured as an integrated object, for example, by pressing using a single plate-like member.

  Further, in each of the above-described embodiments, the basic shape of the segment 11 is basically a rectangular shape in a plan view, but various shapes such as a polygonal shape, a circular shape, and an elliptical shape other than the rectangular shape are used. Can do. That is, in each of the embodiments described above, the outline shape of the entire balance weights 10 to 40 is basically a rectangular shape obtained by combining two rectangular segments 11 in plan view. A typical contour shape is not limited to a rectangular shape. For example, the basic contour shape of the balance weight according to the present invention can be various shapes such as a polygonal shape other than a rectangular shape, a circular shape, and an elliptical shape.

  Moreover, the rotating shafts 100 to 400 with balance weights according to the respective embodiments described above include the rotating shaft 110 and any of the balance weights 10 to 40 fixed to the outer surface F of the rotating shaft 110. According to the rotary shafts with balance weights 100 to 400 according to the present embodiment, the product life can be improved by relaxing the stress concentrated on the welded portion 70.

  As described above, according to the present invention, it is possible to provide the balance weights 10 to 40 that can relieve the stress concentrated on the welded portion 70 with the rotating shaft 110. Further, according to the present invention, it is possible to provide the rotary shafts 100 to 400 with balance weights that can improve the product life.

  The above is an example of various embodiments of the present invention, and various modifications can be made according to the description of the scope of claims. For example, in the balance weights 10 to 40 according to the above-described embodiments, the connecting portion C is connected to the protruding portion 11b of the segment 11, but can be directly connected to the mating portion 11a of the segment 11. That is, according to the present invention, the protruding portion 11b (rising surface 13b) of the segment 11 can be omitted.

  Further, the balance weights 10 to 40 according to each of the above-described embodiments have the outer surface F of the rotating shaft 110 such that the contour line L1 of the segment 11 (the balance weight contour line L3) is arranged in parallel to the axis O. It is fixed against. However, the balance weight according to the present invention is fixed to the outer surface F of the rotating shaft 110 such that the contour line L2 of the segment 11 (the contour line L4 of the balance weight) is arranged parallel to the axis O. You can also.

  In the balance weights 10 to 40 according to the above-described embodiments, the gap G extends in a direction along the contour line L1 of the segment 11 (the contour line L3 of the balance weight) in each plan view. . However, the extending direction of the gap G can be appropriately changed according to the direction of the balance weights 10 to 40 fixed to the rotating shaft 110. Further, the shape, number, and arrangement of the gap G can be changed as appropriate according to the shape, number, and arrangement of the connecting portions C.

  Further, the balance weight can be fastened using a fastening element such as a bolt in addition to welding to the rotating shaft 110. Furthermore, each structure of the balance weight placement and the rotation shaft with balance weight according to each of the above-described embodiments can be appropriately replaced with each other or used in combination.

  10: balance weight (first embodiment), 11: segment, 11a: mating portion, 11b: projecting portion, 12: outer surface of the segment, 13: inner surface of the segment, 13a: mating surface, 13b: rising surface, 14: Inner surface of connecting portion, 15: connecting portion, 18: notch, 18a: notch main body, 18b: notch tip (notch tip side), 18c: notch tip (notch tip side), 18e: notch tip, 19: Hole, 19a: Hole body portion, 19b: Hole tip (hole tip side), 19e: Hole tip, 20: Balance weight (second embodiment), 21: Overhang, 30: Balance weight (Third embodiment), 34: inner surface of connecting part, 35: connecting part, 40: balance weight (fourth embodiment), 44: of connecting part 45: connecting portion, 100: rotating shaft with balance weight (first embodiment), 110: rotating shaft, 200: rotating shaft with balance weight (second embodiment), 300: rotating shaft with balance weight ( Third embodiment), 400: Rotating shaft with balance weight (fourth embodiment), C: connecting portion, d: width of notch (hole), G: gap, L: length of notch (hole), L1: Outline of segment (long side), L2: Outline of segment (short side), L3: Outline of balance weight (short side), L4: Balance weight (long side) ) Contour line, P: Projection, R: Radius of the cutting tip, r: Radius of the cutting tip (hole tip), S: Space, 70: Welded part (fixed part)

Claims (12)

A balance weight fixed to the outer surface of the rotating shaft,
Two segments that are spaced apart from each other and that have a mating surface that can be fixed to the rotating shaft; and at least one connecting portion that connects the two segments;
The balance weight, wherein the at least one connecting portion is a connecting portion that protrudes in an arch shape outside the mating surface of the segments.   The balance weight according to claim 1, wherein the segment has a protruding portion that protrudes together with the at least one connecting portion so as to form a part of the arch shape.   3. The balance weight according to claim 1, wherein the at least one connecting portion defines a gap together with the two segments, and the gap is a cut.   4. The balance weight according to claim 3, wherein the cuts are arranged at two positions sandwiching the connecting portion.   The balance weight according to claim 3 or 4, wherein a contour shape on a front end side of the cut is a semicircular shape in a plan view.   The balance weight according to claim 3 or 4, wherein a contour shape on a front end side of the cut is a circular shape in a plan view.   The balance weight according to claim 1 or 2, wherein the at least one connecting portion is two connecting portions, the two connecting portions define a gap together with the two segments, and the gap is a hole.   The balance weight according to claim 7, wherein the hole is a long hole.   The balance weight according to any one of claims 1 to 8, wherein the segment has a projection for welding on the mating surface of the segment.   The balance weight according to any one of claims 1 to 9, wherein the segment has a welding overhang portion formed by projecting a part of a contour line in plan view of the segment.   The balance weight according to claim 1, wherein the segment is configured by a plate-like segment.   The rotation shaft with a balance weight which has a rotation shaft and the balance weight of any one of Claim 1 thru | or 11 fixed to the outer surface of the said rotation shaft.

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