JPH08312552A - Rotor for fluid machinery - Google Patents

Abstract

PURPOSE: To provide a rotor for fluid machinery, of which weight is reduced and which can reduce the moment of inertia, and furthermore, which can easily balance in the rotational direction. CONSTITUTION: In a rotor for fluid machinery, which compresses the fluid for pressure-feeding with a pair of rotors engaged with each other, a hollow hole 7, which is provided with a wall 5 in one end surface in the axial direction or the intermediate part, is formed inside a tooth thick part 1a of the rotor. One end or both ends of this hollow hole 7 are provided with a balance correcting thick part 9 for correcting the balance in the rotating direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor for a fluid machine in which fluid is compressed and pumped by a pair of rotors meshing with each other.

[0002]

2. Description of the Related Art Conventionally, when a fluid machine as described above is used for an application such as a supercharger for an automobile engine in which the rotational speed changes drastically, if the weight of the rotor is large and the moment of inertia is large, the efficiency is high. Since there is a problem such as deterioration of the rotor, there is a rotor in which the gum portion is thinned out along the axial tooth traces to provide a hollow hole to reduce the weight of the rotor and reduce the moment of inertia.

As a conventional fluid machine of this type, for example, JP-A-4-12189 and JP-A-4-311694 are available.
There is one such as that described in the publication.

The former is a roots-type blower. As shown in FIGS. 6 and 7, this roots-type blower 101 has a rotor housing 103 having a suction port 105 and a discharge port 107 facing each other. Mouth 105, discharge port 107
A rotor chamber 109 communicating with is formed.

In the rotor chamber 109, the rotor housing 1
The first rotor shaft 111 and the second rotor shaft 113, which are rotatably supported by 03, connect the suction port 105 and the discharge port 1 to each other.
It is arranged in a direction perpendicular to the line connecting with 07. A first rotor 115 and a second rotor 117 are axially mounted and fixed to the first rotor shaft 111 and the second rotor shaft 113, respectively, with their phases differing from each other by 90 °.

The convex gingival part 115a of the first rotor 115
Hollow holes 119 and 121 along the axial direction are formed in the flesh portion and the convex gingival portion 117a of the second rotor 117, respectively, to reduce the weight of the rotors 115 and 117 and reduce the moment of inertia. There is.

One end side of each rotor shaft 111, 113 is inserted into a gear chamber 123 provided adjacent to the rotor chamber 109, and in this gear chamber 123, a gear transmission mechanism 125 is interlockingly connected. A drive pulley 127 is attached to the other end side of the first rotor shaft 111.

When a rotational force is input to the drive pulley 127, this rotational force is transmitted to the first rotor 115 via the first rotor shaft 111, and the gear is also transmitted from the first rotor shaft 111. Transmission mechanism 125 and second rotor shaft 11
3 is transmitted in synchronization with the second rotor 117. Then, the first and second rotors 115 and 117 rotate while meshing in a non-contact state, and the fluid sucked from the suction port 105 is compressed by the rotors 115 and 117 and discharged from the discharge port 107.

The latter is a screw compressor 130, and as shown in FIGS. 8 and 9, a male rotor 1 having a plurality of convex gingiva parts 133a inside a casing 131.
33 and a female rotor 135 having a recessed portion 135a that meshes with the gum portion 133a are arranged so as to mesh with each other. Female rotor shaft 1
39 and 39 are respectively mounted and fixed.

A suction port (not shown) is provided on one end side in the axial direction of the casing 131, and a discharge port 141 is provided on the other end side in the axial direction.

Inside the convex gingiva part 133a of the male rotor 133, the hollow hole 1 is formed along the axial direction of each gingiva part 133a.
43 is provided to reduce the weight of the male rotor 133 and reduce the moment of inertia.

It is necessary for the male rotor 133 to block a part of the hollow hole 143. If the hollow hole penetrates from the suction side end surface to the discharge side end surface of the rotor, fluid will flow during operation of the screw compressor. This is because the high-pressure side end face leaks through the hollow hole to the low-pressure side end face.

One end side of each rotor shaft 137, 139 is interlockingly connected by a transmission mechanism (not shown), and the drive pulley 1 is connected to one rotor shaft, for example, the male rotor shaft 137.
45 is attached.

When a rotational force is input to the drive pulley 145, this rotational force is transmitted to the male rotor 133 via the male rotor shaft 137, and the male rotor shaft 137 drives the transmission mechanism and the female rotor shaft 139. It is transmitted in synchronization with the female rotor 135 via. And a pair of male and female rotors 135,
137 rotates in mesh with each other in a non-contact state, compresses the fluid sucked from the suction port, and sends the compressed fluid to the discharge port 141.
Discharge from.

[0015]

By the way, in this type of fluid machine, a pair of rotors are assembled and set with a minute gap between the rotors so that the rotors rotate while meshing with each other in a non-contact state. It is necessary to balance the rotation direction of each rotor for this purpose. Then, the balance adjustment in the rotation direction of the rotor is performed by forming small holes or the like on both end surfaces in the axial direction.

However, in each of the above fluid machines of the prior art, a hollow hole is provided inside the gingiva portion of the rotor for the purpose of reducing the weight of the rotor and reducing the moment of inertia. Also, in the latter conventional example, there is a problem in that there is no balance correction portion for forming a small hole or the like for balancing the rotational direction of the rotor on the axial end surface of the rotor, and the rotational direction balance of the rotor cannot be maintained.

Therefore, an object of the present invention is to provide a rotor for a fluid machine, which can reduce the weight of the rotor and reduce the moment of inertia, and can easily balance the rotational directions.

[0018]

In order to solve the above problems, a rotor of a fluid machine according to a first aspect of the present invention is a rotor of a fluid machine in which fluid is compressed and pumped by a pair of rotors meshing with each other. It is characterized in that a hollow hole having a wall provided at one end surface or an intermediate portion in the axial direction is formed inside, and a balance correcting wall portion in the rotational direction is provided at one end or both ends of the hollow hole.

According to a second aspect of the rotor of the fluid machine, the balance correcting wall portion is provided so as to project into the hollow hole.

[0020]

The rotor has a light weight due to the hollow hole formed in the gingiva. Therefore, the moment of inertia of the rotor is also greatly reduced.

Further, by cutting the balance correcting meat portion provided at one end or both ends of the rotor, the rotor can be easily balanced in the rotating direction.

Further, since the balance correcting wall portion projects into the hollow hole of the rotor, the wall thickness of the rotor can be made sufficiently close to the wall thickness required for strength, and the moment of inertia can be reduced. At the same time, the balance correction meat portion can have a large end surface area, and the cutting process for balance correction becomes easy.

[0023]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front view of a male rotor of a screw fluid machine showing an embodiment of the present invention, FIG. 2 is a cross-sectional view in the tooth trace direction of FIG. 1, and FIG. 3 is a view A as seen from the suction side of FIG. 4 is a side view in the direction of arrow B as seen from the discharge side in FIG. 1.

The male rotor 1 has a fitting hole 3 into which a male rotor shaft (not shown) is fitted, and three convex gingiva parts 1a are formed in a spiral shape coaxially with the fitting hole 3. .

Inside the convex gingiva 1a, each gingiva 1a
A hollow hole 7 is provided in a spiral shape from the suction side end surface toward the discharge side end surface wall 5 along the axial direction.

The suction side end face is provided with a balance correction wall portion 9 for balancing the rotational direction of the male rotor 1 formed so as to project from the outermost diameter side of the rotor wall portion into the hollow hole 7. There is.

The outer peripheral end face 10 of the wall 5 on the discharge side end face also serves as the balance correcting wall portion 10.

The male rotor 1 has a hollow hole 7 formed by precision casting.
And the balance correcting meat portion 9 is secured. In this precision casting, a hole 11 for supporting a core is formed in the wall 5, and this hole 11 is fitted with a pin 13 to close it.

The wall 5 is provided in the hollow hole 7 as described above, because if the hollow hole penetrates from the suction side end surface to the discharge side end surface of the rotor, during operation of the screw fluid machine,
This is to prevent the fluid from leaking from the high pressure side end surface to the low pressure side end surface through the hollow hole.

According to the above construction, the male rotor 1 is made light by the hollow hole 7 provided inside the gum portion 1a. Therefore, the moment of inertia of the rotor 1 is also greatly reduced.

Further, the balance correction meat portion 9 provided on the suction side end surface of the rotor 1 and the balance correction meat portion 10 provided on the discharge side end surface are cut to balance the rotor 1 in the rotational direction. be able to.

Therefore, the screw fluid machine to which the male rotor 1 is applied can operate efficiently for applications such as a supercharger of an automobile engine in which start, stop and acceleration / deceleration are frequently performed. it can.

Further, since the balance correcting wall portion is provided so as to project from the outermost diameter side of the rotor wall portion into the hollow hole 7, the balance of the rotor can be balanced by slightly performing the cutting work at the time of balance correction. It can be done easily and accurately.

FIG. 5 shows another embodiment of the present invention. The same components as those in the above-described embodiment are designated by the same reference numerals, and duplicated description will be omitted.

In this embodiment, the wall 15 is provided at the axially central portion which is the axially intermediate portion of the hollow hole 7. Then, balance correction wall portions 17 and 19 for balancing in the rotational direction are projected into the hollow hole 7 from the outermost diameter side of the rotor wall portion on both end surfaces of the suction side end surface and the discharge side end surface. It is provided. A pin 23 is embedded in the skirting hole 21 of the wall 15.

This embodiment also has the same operation and effect as the above embodiment.

In each of the above-described embodiments, the male rotor 1 has three gum portions 1a, but it goes without saying that the number of gum portions may be other than that.

Further, the invention can be applied not only to the rotor of a screw fluid machine but also to a rotor of a roots type blower or the like.

Further, the balance correction is not limited to cutting, and it is also possible to embed pins having different weights in holes initially provided in the balance correcting meat portion.

[0041]

As is apparent from the above description, in the rotor of the fluid machine according to the first aspect of the present invention, a hollow hole having a wall provided at one axial end surface or an intermediate portion in the axial direction is formed in the gingival portion of the rotor, and one end of the rotor is formed. Alternatively, by providing the balance correcting wall portions in the rotational direction on both ends, the weight and the moment of inertia of the rotor can be significantly reduced, and the rotational direction of the rotor can be easily balanced.

In the rotor of the fluid machine according to the second aspect of the present invention, since the balance correcting wall portion projects into the hollow hole of the rotor, the rotor wall thickness can be made sufficiently thin to the wall thickness required for strength, and the moment of inertia can be reduced. At the same time, the balance correction meat portion can have a large end surface area, and the cutting process for balance correction becomes easy.

[Brief description of drawings]

FIG. 1 is a front view of a male rotor of a screw fluid machine showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line of teeth of FIG.

FIG. 3 is a side view in the direction of arrow A as seen from the suction side of FIG.

FIG. 4 is a side view in the direction of arrow B as seen from the discharge side in FIG.

FIG. 5 is a sectional view in the tooth trace direction showing another embodiment of the present invention.

FIG. 6 is a cross-sectional view of a roots-type blower according to a conventional example.

FIG. 7 is a sectional view taken along the line CC of FIG. 6;

FIG. 8 is a sectional view of a screw compressor according to another conventional example.

9 is a cross-sectional view taken along the line DD of FIG.

[Explanation of symbols]

 1 Male rotor (rotor) 1a Gingival part 5,15 Wall 7 Hollow hole 9,17,19 Balance correcting meat part

Claims (2)

[Claims] 1. In a rotor of a fluid machine for compressing and pumping a fluid by a pair of rotors meshing with each other, a hollow hole having a wall provided at one axial end surface or an intermediate portion is formed inside the gingival portion of the rotor, and the hollow hole is formed. A rotor for a fluid machine, characterized in that one or both ends of a hole are provided with a wall portion for correcting balance in the rotational direction. 2. The rotor of a fluid machine according to claim 1, wherein the balance correction meat portion is provided so as to project into the hollow hole.