JP2610957B2 - Rotor - Google Patents

Description

The present invention relates to a rotor that rotates while meshing with each other, such as a screw rotor of a screw compressor or a pump, a rotor of a sirocco fan, a rotor of a screw pump, and the like.

(Prior art and its problems) This type of screw compressor has a pair of male and female screw rotors that are rotated at high speed while meshing with each other, and sucks gas into a compression space sealed by the meshing of each screw rotor, As the volume of the compression space gradually decreases due to the rotation of the screw rotor, the gas enclosed therein is compressed. The pair of screw rotors are meshed with a small clearance (about 0.1 mm) in order to minimize the leakage of the gas sucked into the compression space and compressed.

A pair of male and female screw rotors of a conventional screw compressor are manufactured by machining high-strength steel materials such as carbon steel for machine structure, and in particular, the screw is a single cutter using a dedicated processing machine. Or it is precisely cut by a hob or the like.

Therefore, this screw rotor requires not only a large number of man-hours for its processing but also a large variation in accuracy due to a cutting error. Also, since the whole is made of steel material,
Due to its large weight and thus large inertia during rotation, a large power is required to start the screw compressor.

In order to reduce the weight of the screw rotor, it has been proposed to manufacture the screw rotor by injection molding of a synthetic resin as disclosed in, for example, JP-A-59-32688.

However, since the use conditions of this kind of screw rotor are severe, the synthetic resin satisfying the characteristics required for the synthetic resin constituting the screw rotor is limited to a material called super engineering plastic. Since the cost of the super engineering plastic is very high, the cost of a component having a large volume, such as a screw rotor of this kind, increases rapidly. Moreover, super engineering plastics have poor moldability during injection molding,
Therefore, it is extremely difficult to mold a component requiring high precision, such as a screw rotor, by injection molding of a super engineering plastic.

In addition, since the coefficient of thermal expansion of synthetic resin is larger than that of steel material, when each screw rotor thermally expands due to its temperature rise during operation of the screw compressor, an appropriate minute clearance is maintained between these screw rotors. In a severe case, the respective screw rotors may come into direct contact with each other and be damaged.

(Means for Solving the Problems) The present invention was invented to solve the above problems, and the gist of the first invention is that one synthetic resin layer or two or more synthetic resin layers Are laminated in the radial direction and rotate while meshing with each other. The material of the surface layer of each rotor is an ethylene-tetrafluoroethylene copolymer reinforced with 5 to 30% by weight of carbon fiber. A rotor characterized by the above.

Further, the gist of the second invention is that in a rotor in which one synthetic resin layer or two or more synthetic resin layers are laminated in the radial direction and rotate while meshing with each other, the material of the surface layer of one rotor Is an ethylene-tetrafluoroethylene copolymer reinforced with 5 to 30% by weight of carbon fiber, and the material of the surface layer of the other rotor meshing with one rotor is made of carbon fiber, glass fiber and inorganic filler. A reinforced polyphenylene sulfide resin obtained by adding 30 to 70% by weight in total of one or more selected from the group consisting of:

Further, the gist of the third invention is that in a rotor in which one synthetic resin layer or two or more synthetic resin layers are laminated in the radial direction and rotated while meshing with each other, the material of the surface layer of one rotor Is an ethylene-tetrafluoroethylene copolymer reinforced with 5 to 30% by weight of carbon fiber, and the material of the surface layer of the other rotor that meshes with one rotor is reinforced with carbon fiber and / or glass fiber. The rotor is a phenol resin.

(Function) In the present invention, since the rotor has the above configuration, when the rotor thermally expands due to a rise in temperature, the surface layer made of the ethylene-tetrafluoroethylene copolymer wears out and becomes powdery and falls off. However, an appropriate minute clearance is automatically maintained between the respective rotors.

(Embodiment) One embodiment of the present invention is shown in FIG.

Reference numeral 1 denotes a male rotor, a metal shaft 1a made of steel or the like.
And a core layer 1b fixed to the outer periphery of the shaft 1a, and a surface layer 1c covering the core layer 1b. The core layer 1b and the surface layer 1c are laminated in the radial direction by injection-molding a synthetic resin, respectively.
1d is formed.

Reference numeral 2 denotes a female rotor, which is a metal shaft 2a made of steel or the like.
And a core layer 2b fixed to the outer periphery of the shaft 2a, and a surface layer 2c covering the core layer 2b. These core layers
The 2a and the surface layer 2c are each laminated in the radial direction by injection-molding a synthetic resin to form six screws 2d.

The male rotor 1 and the female rotor 2 are engaged with each other as shown in the figure, and are driven to rotate in opposite directions. Then, the gas is sucked into the compression space sealed by the engagement of the male rotor 1 and the female rotor 2, and the gas sealed therein is reduced as the volume of the compression space is reduced by the rotation of the rotors 1 and 2. Compress.

Each of the core layer 1b of the male rotor 1 and the core layer 2b of the female rotor 2 is reinforced by adding 40% by weight of a total of one or more selected from glass fiber, carbon fiber and inorganic filler. Made of sulfide resin,
Both the surface layers 1c and 2c are made of an ethylene-tetrafluoroethylene copolymer reinforced with 20% by weight of carbon fibers. The content of carbon fibers added to the surface layers 1c and 2c is desirably 5 to 30% by weight, preferably 10 to 20% by weight.

In the actual operation of the screw compressor, when the temperature of the male rotor 1 and the female rotor 2 rises and thermally expands, the surface layers 1c and 2c come into contact with each other, and one or both surfaces thereof are worn. And fall off in powder form.

Thus, an appropriate reduced clearance is automatically formed between the male rotor 1 and the female rotor 2, so that the leakage of the gas compressed in the compression space is suppressed, and the male rotor 1 and the female rotor 2 vibrate. It rotates smoothly without generating noise.

(Second Embodiment) The screw 2d of the female rotor 2 has a small thickness. Therefore, when the surface layer 2c is provided, the thickness of the core layer 2b, which is responsible for the strength, is reduced. In some cases, the surface layer 2c is 40% by weight glass fiber and 25% by weight.
Of polyphenylene sulfide resin reinforced with an inorganic filler. It should be noted that carbon fibers can be added to the surface layer 2c in order to prevent generation of sparks due to static electricity. The total content of carbon fiber, glass fiber and inorganic filler is 30 to 70% by weight, preferably 60 to 70% by weight.
It is desirably about 65% by weight. The male rotor 1 is configured in the same manner as in the first embodiment.

When the screw compressor is in operation, the male rotor 1
When the female rotor 2 thermally expands due to a rise in temperature, the surface layer 1c of the male rotor 1 wears out and becomes powdery and falls off, and an appropriate minute clearance is automatically provided between the male rotor 1 and the female rotor 2. Formed. And the screw of the female rotor 2
Since 2d has sufficient strength, no strength problem occurs.

Third Embodiment The female rotor 2 is composed of a single synthetic resin layer made of a phenol resin reinforced with glass fibers and / or carbon fibers.
This phenolic resin is a thermosetting resin and has a small shrinkage,
Therefore, high accuracy can be obtained only by this. The male rotor 1 is configured in the same manner as in the first embodiment.

Then, when the screw compressor is in operation, the male rotor 1
When the female rotor 2 expands thermally, the surface layer 1c of the male rotor 1
Is worn and powdered and falls off, so that an appropriate minute clearance is automatically formed between the male rotor 1 and the female rotor 2.

Although the example in which the present invention is applied to a pair of male and female screw rotors of a screw compressor has been described above, the present invention is also applied to three or four or more screw rotors of a sirocco fan and a screw pump that mesh with each other. It goes without saying.

(Effects of the Invention) In the present invention, the material of the surface layer of the rotor that rotates while meshing with each other is an ethylene-tetrafluoroethylene copolymer reinforced with 5 to 30% by weight of carbon fiber. At the time of thermal expansion, one or both of the surface layers made of the ethylene-tetrafluoroethylene copolymer come into contact with each other and become worn and fall off as a powder, so that an appropriate minute clearance between the rotors is obtained. It is formed automatically. As a result, the rotor rotates smoothly without generating vibration and noise while suppressing fluid leakage from these gaps. Since these rotors can be formed by injection molding a general-purpose synthetic resin, they can be manufactured at low cost, with low cost, and with high precision.

The material of the surface layer of one rotor is an ethylene-tetrafluoroethylene copolymer reinforced with 5 to 30% by weight of carbon fiber, and the material of the surface layer of the other rotor that meshes with the one rotor is If one or more selected from carbon fibers, glass fibers and inorganic fillers are synthesized and reinforced by adding 30 to 70% by weight to obtain a reinforced polyphenylene sulfide resin, one surface of the other rotor may be used depending on the surface layer of the other rotor. The surface layer of the rotor is scraped off, so that an appropriate minute clearance is automatically formed between the rotors, and the other rotor can maintain sufficient strength.

Further, the material of the surface layer of one of the rotors is an ethylene-tetrafluoroethylene copolymer reinforced with 5 to 30% by weight of carbon fiber, and the material of the surface layer of the other rotor meshing with the one rotor is If phenolic resin reinforced with carbon fiber and / or glass fiber is used, the other rotor will scrape off the surface layer of one of the rotors and automatically create an appropriate minute clearance between these rotors while the other rotor will Since it can be a single layer, it can be manufactured at lower cost.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention. Male screw rotor ... 1, screw ... 1d, shaft ...
1a, surface layer 1c, core layer 1b, female screw rotor 2 screw 2d, shaft 2a, surface layer 2c, core layer 2b

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Satomi Murata 9-35, Horita-dori, Mizuho-ku, Nagoya-shi, Aichi Prefecture Inside Brother Industries, Ltd. (72) Inventor Masumi Sekita 3 Asahimachi, Nishibiwajima-cho, Nishi-Kasugai-gun, Aichi Prefecture 1-chome, Mitsubishi Heavy Industries, Ltd. Air Conditioner Works (72) Inventor Hideo Kuroda 1, Takamichi, Iwazuka-cho, Nakamura-ku, Nagoya-shi, Aichi Pref.

Claims (3)

(57) [Claims] 1. A rotor in which one synthetic resin layer or two or more synthetic resin layers are laminated in the radial direction and rotate while meshing with each other, the material of the surface layer of each rotor is 5-30.
A rotor characterized in that it is an ethylene-tetrafluoroethylene copolymer reinforced by weight% of carbon fibers. 2. A rotor in which one synthetic resin layer or two or more synthetic resin layers are laminated in the radial direction and rotate while meshing with each other, the material of the surface layer of one rotor is 5 to 30% by weight of carbon. An ethylene-tetrafluoroethylene copolymer reinforced with fibers, and one or more materials selected from carbon fibers, glass fibers, and inorganic fillers for a material of a surface layer of the other rotor that meshes with one rotor. 30 to 70
A rotor characterized in that it is a polyphenylene sulfide resin reinforced by adding weight%. 3. A rotor in which one synthetic resin layer or two or more synthetic resin layers are laminated in the radial direction and rotate while meshing with each other, and the material of the surface layer of one rotor is 5 to 30% by weight of carbon. Fiber-reinforced ethylene-tetrafluoroethylene copolymer, characterized in that the material of the surface layer of the other rotor meshing with one of the rotors is a phenolic resin reinforced with carbon fibers and / or glass fibers. Rotor.