JPH11125233A - Drive shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive shaft which has a practical length and is furnished with a very low torsion rigidity and a high bending rigidity sustaining a high speed rotation. SOLUTION: A drive shaft is embodied as a multi-layer body consisting of cylinders 3-1 through 3-3 (or solid pieces) made of a elastic material and having different diameters. One end of the cylinder 3-1 of maximum diameter is fixed to a fixing member 2b to be attached to one of the rotary shafts while one end of the cylinder 3-3 of minimum diameter is fixed to another fixing member 2a to be attached to the other rotary shaft. Using mounting aid members 4a and 4b, the ends of multi-layer cylinders are fastened one by one so that the section appears folded-up. The cylinders are positioned with gaps in between, and the mounting aid members 4a and 4b are supported by bearings 5a and 5b rotatably with respect to the fixing members 2a and 2b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a motor and a rotating machine,
The present invention relates to a drive shaft used to connect rotating bodies such as a prime mover and a generator, and a prime mover and a gear unit.

[0002]

2. Description of the Related Art The rotational force of a prime mover or an electric motor is normally transmitted to a load such as a generator or a gear unit via a drive shaft. FIG.
As shown in (1), when rotating bodies having inertia values J1 and J2 are coupled via a drive shaft having a torsion spring constant of K, the torsion resonance frequency f is expressed by the following equation (1).

F = (1 / 2π) √ (K / J) (1) Here, 1 / J = (1 / J1) + (1 / J2).
That is, in order to reduce the torsion resonance frequency, it is necessary to reduce the torsion spring constant K of the drive shaft according to the inertia value of the rotating body. For example, to couple rotating bodies having extremely small inertia values, the torsion spring constant is required. It is necessary to use a small drive shaft. In particular, a drive shaft having a low torsion rigidity and a high bending rigidity is required to connect a rotating body having a small inertia value that rotates at a high speed. However, such a drive shaft has not been conventionally provided.

[0004]

The following method can be considered as a method for realizing a drive shaft that withstands high-speed rotation and has a small torsional resonance frequency. As shown in FIG. 7A, a drive shaft is formed by using a new material or a composite material having ultra-low torsional rigidity and high bending rigidity. In recent years, various new materials and composite materials have been developed, but it is difficult to obtain materials having low torsional stiffness and high bending stiffness, and it is difficult to realize a drive shaft satisfying the above requirements using these materials. . Fig. 7 shows a drive shaft with high bending rigidity that can rotate at high speed.
By providing a plurality of intermediate bearings and connecting them in series as shown in (b), a drive shaft having a required torsion spring constant is realized.

According to this method, it is possible to realize a drive shaft that satisfies the above-mentioned requirements by using currently available materials. However, in this method, the entire length of the drive shaft is extremely long. (The length of the drive shaft is usually 500m
m to about 1500 mm is a practical length). Further, there is no practicality in terms of space and cost, such as the need to provide several intermediate bearings. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a drive shaft having both a very low torsional rigidity and a high bending rigidity to withstand high-speed rotation, and a practical length. That is.

[0006]

According to the present invention, the above-mentioned problems are solved as follows. (1) In a drive shaft having a pair of fixed members connected to a rotating body, the drive shaft is constituted by a plurality of cylindrical bodies having different diameters and a multilayer body including a cylinder or a solid body having a minimum diameter. Then, one end of the cylinder having the maximum diameter of the multilayer body is fixed to one of the fixing members, and one end of the cylinder or the solid body having the minimum diameter of the multilayer body is fixed to the other of the fixing members. The other end of the cylindrical body having the diameter and one end of the cylindrical body on the inner diameter side are fixedly provided, and the other end of the cylindrical body on the inner diameter side and one end of the cylindrical body on the inner diameter side of the cylindrical body are fixedly provided. . Similarly, by sequentially fixing the end portions of the multilayered cylindrical body or solid body so that the cross-section thereof is folded, the multilayered cylindrical body or solid body is connected in series. Connecting.

(2) In the above (1), the ends of the cylindrical body or the solid body are fixed so that a gap is formed in at least a part of the multilayer body of the cylindrical body or the solid body. (3) In the above (1) and (2), at least a portion between the fixed portion of the cylinder or the solid and the fixed portion of the cylinder and at least a portion between the fixed portion of the cylinder or the solid and the fixing member, A support member is provided for rotatably supporting the fixed portion of the outer cylindrical body. (4) In the above (1), (2), and (3), at least a part of the cylindrical body and the fixed portion of the cylindrical body are fixedly mounted by a mounting member, and the space between the mounting members and between the mounting members, A support member for rotatably supporting the fixed portion or the mounting member of the outer cylindrical member is provided between the fixing members or between the mounting member and the fixed portion.

[0008] In the invention of claims 1 to 4 of the present invention,
By sequentially fixing the ends of the cylindrical body or the solid body formed as described above so that the cross section thereof becomes a folded shape, the cylindrical body or the solid body formed in the multilayer is connected in series. Since the drive shaft is formed as described above, it is possible to obtain a drive shaft having both low torsional stiffness and high bending stiffness to withstand high-speed rotation and having a practical length. In addition, the fixed portion of the cylindrical body on the outer diameter side is provided between the fixed portion of the cylindrical body or the solid body and the fixed portion of the cylindrical body and at least a part between the fixed portion of the cylindrical body or the solid body and the fixing member. By providing a support member for rotatably supporting the drive shaft, a drive shaft having higher bending rigidity can be obtained.

[0009]

FIG. 1 is a view showing a drive shaft according to a first embodiment of the present invention. FIG. 1 is a sectional view taken along a plane passing through the axis of the drive shaft 1. FIG. In FIG. 1, reference numeral 1 denotes a drive shaft, and reference numerals 2a and 2b denote fixing members attached to a rotating body. The fixing member 2b is composed of fixing members 2b-1 and 2b-2, and the fixing member 2b-1 is fitted to the fixing member 2b-2, and the fixing member 2b-
The mounting position of the fixing member 2b-1 with respect to 2 is adjustable. 3-1 to 3-3 are a plurality of cylindrical bodies having different diameters, and the cylindrical bodies 3-1 to 3-3 are, for example, carbon fiber, iron-based, plastic-based, rubber-based, or a composite material of the above-described materials. Of elastic members. Note that the cylindrical body 3-3 having the minimum diameter may be a solid body.

The cylindrical bodies 3-1 to 3-3 are formed in a multilayer structure. One end of the cylindrical body 3-1 having the largest diameter is attached to the fixing member 2b, and one end of the cylindrical body 3-3 having the smallest diameter is fixed to the fixing member 2b. 2a
Attached to. The other end of the cylindrical body 3-1 having the largest diameter is fixed to the mounting member 4a, and the mounting member 4a is fixed to the fixing member 2a by the bearing 5a attached to the fixing member 2a.
Is supported so as to be rotatable. One end of a cylindrical body 3-2 is attached to the mounting member 4a, and a protrusion 4at is formed on the mounting member 4a so that a predetermined gap is formed between the cylindrical bodies 3-1 and 3-2. Is provided.

The other end of the cylindrical body 3-2 is connected to a mounting member 4b.
The mounting member 4b is rotatably supported by the fixed member 2b by a bearing 5b attached to the fixed member 2b. The other end of the above-described minimum diameter cylindrical body 3-3 is attached to the mounting member 4b, and a predetermined gap is formed between the cylindrical bodies 3-2 and 3-3 in the mounting member 4b. Protrusion 4bt is provided as described above.

In FIG. 1, a fixing member 2a is fixed,
When the fixing member 2b is twisted, the maximum diameter cylindrical body 3-1 is formed.
Are twisted, and the twist imparts a twist to the cylindrical body 3-2 via the attachment member 4a, and the twist twists the cylindrical body 3-3 via the attachment member 4b. Assuming that the torsional rigidity of the fixing members 2a and 2b and the attaching members 4a and 4b is much larger than that of the cylindrical bodies 3-1 to 3-3, the torsion rigidity is substantially determined by the cylindrical bodies 3-1 to 3-3. Would. That is, assuming that the torsion spring constants of the cylindrical bodies 3-1 to 3-3 are K1, K2, and K3, respectively, the total torsion spring constant K is connected in series, and is expressed by the following equation (2).

1 / K = (1 / K1) + (1 / K2) + (1 / K3) (2) Therefore, the total torsion spring constant K is calculated as the required torsion resonance frequency f [the above-mentioned equation ( 1)], the length, thickness, and diameter of each of the cylindrical bodies 3-1 to 3-3 are selected, and the torsion spring constants K1, K2, and K3 are determined.
A drive shaft having desired characteristics can be obtained.

On the other hand, as is apparent from FIG. 1, the cylinders 3-1 to 3-3 have a function of reinforcing each other against bending and increasing the bending rigidity, thereby increasing the bending rigidity. Bending rigidity can be obtained and high-speed rotation is possible. Also, bearings 5a, 5 engaged with the mounting members 4a, 4b
b, and cylindrical bodies 3-1 to 3-3 are formed by bearings 5a and 5b.
In addition, since the axes of the mounting members 4a and 4b are maintained, runout during high-speed rotation can be avoided.

Since the drive shaft of this embodiment is formed by connecting three cylindrical bodies in series in a folded manner as described above,
Using a currently available material, a drive shaft having very low torsional rigidity and high bending rigidity to withstand high-speed rotation can be obtained without lengthening the drive shaft. By using the drive shaft of the present embodiment as a configuration of this embodiment, a drive shaft having a length of about 1 m, a low torsion spring constant capable of twisting at an angle of 60 ° or more at both ends of the drive shaft, and, for example, 1
A drive shaft having high bending stiffness that can be used at a high speed rotation of 000 rpm or more was obtained.

In the embodiment described above, the drive shaft is a multilayer body composed of three cylinders. However, the number of layers of the cylinder can be appropriately selected according to the required torsion spring constant. Further, in the above embodiment, the end of the cylindrical body is fixed to the attachment member, and the attachment member is rotatably attached to the fixed member by a bearing. However, the attachment member is not necessarily attached to the end of the cylinder. It is not necessary to attach, and the cylinders themselves may be fixed to each other. Further, in the above embodiment, the gap is formed between the layers of the cylindrical body. However, when the cylindrical body is made of a material having a small coefficient of friction, the gap is not necessarily provided.

Hereinafter, another embodiment of the present invention will be described. FIG. 2 is a view showing a second embodiment of the present invention, in which a drive shaft is composed of five cylindrical bodies, a bearing is provided on a mounting member, and the mounting member on the outer diameter side is rotatable. This embodiment shows a supported embodiment, which is a sectional view taken along a plane passing through the axis of the drive shaft 1 as in FIG. In the figure, 1 is a drive shaft, 2a and 2b are fixing members, and 3-1 to 3-5 are a plurality of cylinders having different diameters. As described above, for example, carbon fiber, iron, plastic, It is formed of an elastic member such as a rubber material or a composite material of the above materials.

The cylindrical bodies 3-1 to 3-5 are formed in a multilayer structure as described above. One end of the cylindrical body 3-1 having the largest diameter is attached to the fixing member 2b, and one end of the cylindrical body 3-5 having the smallest diameter. Is attached to the fixing member 2a. The other end of the cylindrical body 3-1 having the largest diameter is fixed to the mounting member 4a1, and the mounting member 4a1 is fixed to the mounting member 4a2 by a bearing 5a1 mounted on the mounting member 4a2 on the inner diameter side. It is rotatably supported. Further, the mounting member 4a1 has a cylindrical body 3-
2 is attached to the mounting member 4a1, and the cylindrical member 3
The projection 4t1 is provided so that a predetermined gap is formed between -1 and 3-2.

The other end of the cylindrical body 3-2 is connected to a mounting member 4b.
1 and the mounting member 4b1 is a mounting member 4b on the inner diameter side.
2 is rotatably supported by the mounting member 4b2 by a bearing 5b1 mounted on the mounting member 4b2. Also, the mounting member 4b
1 is provided with one end of a cylindrical body 3-3.
A projection 4t3 is provided on b1 so that a predetermined gap is formed between the cylindrical bodies 3-2 and 3-3.

Similarly, the other end of the cylindrical body 3-3 is attached to the attachment member 4a2, and the attachment member 4a2 is attached to the fixing member 2a.
One end of a cylindrical body 3-4 is attached to the mounting member 4a2 so as to be rotatable by a bearing 5a1 attached to the cylindrical member 3a. Further, the other end of the cylindrical body 3-4 is attached to the mounting member 4
b2, the mounting member 4b2 is supported by a bearing 5b2 mounted on the fixed member 2b.
One end of a cylindrical body 3-5 having a minimum diameter is attached to b2. The other end of the cylindrical body 3-5 having the smallest diameter is a fixing member 2
a. Then, the attachment members 4a2, 4b2
Of the cylindrical bodies 3-3 and 3-3
4. A predetermined gap is formed between the cylindrical bodies 3-4 and 3-5.

In the present embodiment, as described above, the mounting members are rotatably supported via the bearings, so that the drive shaft is constituted by a multilayer body composed of an arbitrary number of cylindrical bodies. Can be. For this reason, it has lower torsional rigidity,
A drive shaft having high bending rigidity that can withstand high-speed rotation can be obtained.

FIG. 3 is a view showing a third embodiment of the present invention. In this embodiment, the end portions of the cylindrical bodies are directly fixed without forming a gap between the cylindrical bodies. 1, which is a cross-sectional view taken along a plane passing through the axis of the drive shaft 1 as in FIG. The configuration of the present embodiment is the same as that shown in FIG. 1. In this embodiment, no mounting member and no bearing are provided, and a gap is formed between the cylindrical bodies 3-1 to 3-3. Instead, one end of the cylindrical body 3-1 and one end of the cylindrical body 3-2, the other end of the cylindrical body 3-2 and one end of the cylindrical body 3-3 are fixed to the fixed portion 4ak,
4bk directly fixed. In the present embodiment, since the above configuration is adopted, even if the number of layers of the multilayer body is increased, the number of parts does not increase so much, and the configuration can be relatively simplified. In this embodiment, since no gap is provided between the cylinders, it is desirable to provide a lubricant between the cylinders or to use a cylinder having a relatively small friction coefficient.

FIGS. 4 and 5 are views showing a modification of the second embodiment. FIG. 4 shows a cylindrical body 3-1 to 3-1 provided with no mounting member.
-5 are directly fixed at the fixed portions 4k1 to 4k4, and the ends of the cylinders are deformed to form gaps between the cylinders 3-1 to 3-5. Bearings 5a1 to 5b2 are attached to 4k4, and fixed portions 4k1 to 4k4 are rotatably supported by fixed members 2a and 2b by bearings 5a1 to 5b2. In the present embodiment, since the configuration is as described above, the mounting member is unnecessary and the number of parts can be reduced.

FIG. 5 shows that 3-1 to 3-5 are directly fixed at the fixed portions 4k1 to 4k4 without mounting members.
By deforming the ends of the cylindrical bodies 3-1, 3-2, 3-5, the cylindrical bodies 3-1 and 3-2, the cylindrical bodies 3-2 and 3-3, and the cylindrical body 3-
A gap is formed between 4 and 3-5, fixed portions 4k1 and 4k2 are rotatably supported by fixed members 2a by bearings 5a1 and 5a2, and fixed portions 4k4 are fixed to fixed member 2b.
Is rotatably supported by a bearing 5b1. Also in this embodiment, as in the embodiment of FIG. 4, the mounting member is unnecessary and the number of parts can be reduced. Further, the number of bearings can be made smaller than in the case of FIG.

In the above embodiment, the case where the drive shaft is constituted by using a plurality of cylinders of the same material has been described. However, not all the cylinders need to be made of the same material. The material of the cylindrical body may be appropriately selected according to the required torsion spring constant such as making the cylindrical body (for example, a cylindrical body having the maximum diameter) rigid. In addition, whether the cylindrical body or the solid body and the cylindrical body are directly fixed, or fixed using a mounting member can be appropriately selected as necessary, for example,
In FIG. 1, a cylindrical body 3-3 having a minimum diameter and a cylindrical body 3-3 are formed.
2 is fixed directly without using a mounting member, and the cylindrical body 3-2
The end of the cylindrical body 3-3 having the maximum diameter may be fixed using a mounting member.

[0026]

As described above, according to the present invention, the end of a multilayered cylinder or solid body is
The drive shaft was formed by connecting the above-mentioned multilayered cylindrical body or solid body in series by sequentially fixing them so that their cross-sections were folded, so that high bending that could withstand low torsional rigidity and high-speed rotation A drive shaft having both rigidity and a practical length can be obtained. Therefore, it is possible to realize a high-speed rotation drive shaft that connects rotating bodies having a small inertia value. In addition, the fixed portion of the cylindrical body on the outer diameter side is provided between the fixed portion of the cylindrical body or the solid body and the fixed portion of the cylindrical body and at least a part between the fixed portion of the cylindrical body or the solid body and the fixing member. By providing a support member for rotatably supporting the drive shaft, a drive shaft having higher bending rigidity can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a drive shaft according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of a drive shaft according to a second embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a drive shaft according to a third embodiment of the present invention.

FIG. 4 is a diagram showing a modification of the second embodiment.

FIG. 5 is a diagram showing another modification of the second embodiment.

FIG. 6 is a diagram illustrating a torsional resonance frequency in a drive shaft.

FIG. 7 is a diagram illustrating a method for reducing a spring constant of a drive shaft.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drive shaft 2a, 2b Fixed member 3-1-3-5 Cylindrical body 5a, 5b Bearing 5a1, 5a2, 5b1, 5b2 Bearing 4a, 4b Mounting member 4a1, 4a2, 4b1, 4b2 Mounting member 4at, 4bt, 4t1 4t4 Projection 4ak, 4bk Fixed part 4k1-4k4 Fixed part

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuichiro Ueno 3--8, Fukuura, Kanazawa-ku, Yokohama-shi, Kanagawa-ken Toyo Electric Manufacturing Co., Ltd. Yokohama Works

Claims (4)

[Claims] 1. A drive shaft having a pair of fixed members connected to a rotating body, wherein the drive shaft is constituted by a plurality of cylinders having different diameters and a multilayer body composed of a cylinder or a solid body having a minimum diameter, One end of a cylinder having the maximum diameter of the multilayer body is fixed to one of the fixing members, and one end of a cylinder or a solid body having a minimum diameter of the multilayer body is fixed to the other of the fixing members. The other end of the cylindrical body and one end of the inner diameter side of the cylindrical body are fixedly provided, and the other end of the inner diameter side of the cylindrical body and one end of the inner diameter side of the cylindrical body are fixedly provided. Similarly, by sequentially fixing the ends of the cylindrical body or solid body formed in the above-mentioned multilayer so that the cross section thereof is folded,
A drive shaft characterized by connecting the above-mentioned multilayered cylindrical body or solid body in series. 2. An end of a cylindrical body or a solid body is fixed so that a gap is formed in at least a part of the layers of the multilayer body or the solid body. Drive shaft. 3. An outer diameter side cylindrical body is provided between the fixed part of the cylindrical body or the solid body and the fixed part of the cylindrical body and at least a part between the fixed part of the cylindrical body or the solid body and the fixing member. 3. The drive shaft according to claim 1, further comprising a support member rotatably supporting the fixed portion. 4. The cylindrical body and at least a part of the fixed portion of the cylindrical body are fixedly mounted by a mounting member, and
A support member is provided between the attachment member and the fixed member, or between the attachment member and the fixed portion, the support member rotatably supporting the fixed portion or the attachment member of the cylindrical body on the outer diameter side. The drive shaft according to claim 1, 2 or 3.