JPH01182590A - Noncontact driving device for oilless screw compressor - Google Patents

Abstract

PURPOSE:To disuse a gear and lubricating oil for the gear by providing a plurality of plate type disks whose gear tooth ends are formed into electromagnets and giving attracting force in the direction in which the gap between the tooth ends gets smaller while giving repelling force in the direction in which the gap gets larger. CONSTITUTION:In a compressor, a male rotor 1 and a female rotor 2 which are housed in a casing 4 are mutually engaged, to compress air. A motor 3 is linked to the male rotor 1. A plurality of plate type electromagnets 5 are installed on the end portion of the shaft of each rotor 1, 2, and the tooth ends thereof of each rotor 1, 2 are mutually opposed via a minute gap. A coil 8 installed on each tooth end is fed with a voltage through a voltage control device 7 via a slip ring 6. In this case, an attracting force is given in the direction in which the gap between the tooth end gets smaller while giving a repelling force in the direction in which the gap gets larger, and each rotor 1, 2 is synchronously rotated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a drive device for a screw compressor, and particularly to a device for non-contactly driving a male and female rotor suitable for an oil-free screw compressor.

(Prior art) Conventional drive devices generally use gears to increase the rotation speed of the motor in order to adjust the timing between the rotors in an oil-free screw compressor, and the gear arrangement is not practical. As described in Japanese Patent Application No. 53-57307, improvements were made to the timing technology.

[14 Problems to be Solved by the Invention] The above conventional technology uses oil to lubricate a part of the gear, and a shaft seal is provided to prevent this oil from going to the rotor and prevent it from entering the compressed air. However, there is a possibility of contamination due to defects in the shaft seal, and since the gear rotates at high speed, the vibration and noise inherent to the gear are high, which is a drawback of the oilless type.

An object of the present invention is to provide an oil-free screw compressor that improves product quality by reducing noise caused by gears and preventing lubricant from getting mixed in.

[Means to solve the problem]

The above purpose is to eliminate the gear and its lubricating oil piping. Instead of gears, multiple plate-shaped electromagnets with coils wound around the teeth of the gears are attached to the shaft of the rotor, stacked one on top of the other, with the tips of the teeth slightly shifted. Electromagnets of the same size and number are attached to the shaft of each rotor, and the tips of the teeth are arranged so that there is a slight gap between them. Immediately before operation, a voltage is applied to the electromagnet to create an attractive force in the direction where the gap between the tooth tips becomes smaller and a repulsive force in the direction where the gap between the tooth tips becomes larger. This allows for proper starting timing. When the male rotor rotates and operates, the position of the tooth tip changes and the electromagnetic force becomes stronger, which transmits the rotation to the female rotor and causes it to operate in synchronization. This is achieved by allowing the male and female rotors to maintain a constant gap and engage and rotate without contact.

[Effect]

Apply a voltage to the electromagnet installed on the shaft of the male/female rotor in the direction that reduces the gap between the tooth tips.

Furthermore, when a repulsive voltage is applied in the direction that increases the gap between the tooth tips, a constant gap is formed between the rotors due to magnetic force.

Therefore, by controlling the voltage when starting rotation, backlash can be kept constant and collision between the rotors can be prevented. It can also be used as a brake if the voltage is controlled during driving. As a result, the male and female rotors can be operated with a constant gap, allowing the non-contact compressor to be driven.There is no source of noise, there is no lubricating oil system, and there is no oil mixed into the supplied air.

〔Example〕

An embodiment of the present invention will be described above with reference to FIG.

The compressor has a male rotor 1 and a female rotor 2 built into a casing 4 that mesh with each other to compress air. A motor 3 is connected to the male rotor 1. A plurality of plate-shaped electromagnets 5 are attached to the ends of the shafts of the male rotor 1 and the female rotor 2, and the tips of their teeth face each other with a slight gap. The plate-shaped electromagnet 5 has the shape of a gear, and an electromagnetic coil 8 is attached to each tooth portion.

Voltage is supplied to the coil 8 at each tooth tip from the voltage control device 7 via the slip ring 6, and before operation, the coils 8 at the portions in contact with the male and female rotors attract each other in the direction where the tooth tip gap becomes smaller. , the position is determined by the repulsive force in the direction where the gap is wide (larger).When the operation starts, as the male rotor 1 rotates, the attraction and repulsive force become stronger due to the displacement of the tooth tips of the plate electromagnet 5, and the male rotor 1 rotates in the opposite direction. The female rotor 2 rotates in synchronization.

Figure 2 shows a combination of plate-shaped electromagnets in which a plurality of electrode stones are stacked one on top of the other in a slightly shifted manner to increase magnetic force and reduce rotation errors. According to this embodiment, since gears and lubricating oil piping can be eliminated, the disadvantages of products such as noise, vibration, and oil leakage can be eliminated, resulting in a great effect.

〔Effect of the invention〕

According to the present invention, it is possible to eliminate the gears that cause noise and the gear lubricating oil that gets mixed into the compressed air, and to adjust the timing by electrical control. In addition, stable rotation can be obtained by using a combination of plate-shaped electromagnets to counter unbalanced rotation.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a compressor main body according to an embodiment of the present invention;
The figure is a cross-sectional view of a plate-shaped electromagnet. DESCRIPTION OF SYMBOLS 1... Male rotor, 2... Female rotor, 3... Motor, 4... Casing, 5... Plate electromagnet, 6... Slip ring, 7... Voltage control device,
8... Electromagnetic Koino ν. − Yahe agent Patent attorney Masaru Koyo, male “ ゛＼−−

Claims (1)

[Claims] 1. In the drive part of an oil-free screw compressor, which consists of a motor, a pair of male and female rotors, a gear for connecting and driving them, and a casing that houses the gear, the tooth tip of the gear is used instead of the gear. A plurality of plate-shaped discs using electromagnets are installed with the tips of the teeth slightly shifted relative to one axis, and the above plate-shaped discs are attached to the other shaft in the same way, so that the tips of the teeth have a slight gap between the axes. The female rotor rotates synchronously with the rotation of the male rotor by applying suction force in the direction where the gap between the tooth tips becomes smaller and applying repulsive force in the direction where the gap becomes larger. An oil-free, non-contact drive device.