CN111030419A

CN111030419A - High-temperature-resistant cylindrical magnetic coupling

Info

Publication number: CN111030419A
Application number: CN201911341296.2A
Authority: CN
Inventors: 周晓峰; 王敏; 王慧斌
Original assignee: Zhejiang Jianrun Technology Co Ltd
Current assignee: Zhejiang Jianrun Technology Co Ltd
Priority date: 2019-12-24
Filing date: 2019-12-24
Publication date: 2020-04-17

Abstract

The invention belongs to the field of machinery, and particularly relates to a high-temperature-resistant cylindrical magnetic coupling. The cylindrical magnetic coupling comprises an outer rotor, an isolation sleeve and an inner rotor, wherein a permanent magnet is arranged on the outer rotor, a groove is formed in the outer side of the inner rotor, the inner magnet is embedded into the groove, and the opening of the groove is sealed through a non-conductor material. The invention uses non-conductor material to isolate high temperature medium, so the permanent magnet (inner magnet) on the inner rotor has no direct contact with the high temperature medium, and can isolate or slow down the diffusion of medium temperature, thereby reducing the influence of medium temperature on the high temperature demagnetization of the permanent magnet, therefore, the magnetic coupling has no strict requirement on the temperature of the transmission medium, and can be used in the occasion of transmitting high temperature medium.

Description

High-temperature-resistant cylindrical magnetic coupling

Technical Field

The invention belongs to the field of machinery, and particularly relates to a high-temperature-resistant cylindrical magnetic coupling.

Technical Field

The cylindrical magnetic coupling is a new type coupling which can make use of the magnetic force between rare earth permanent magnets and can make mechanical transmission without mechanical connection. The structure of the cylinder type magnetic coupling commonly used at present mainly comprises three parts, namely a driving (outer) magnetic rotor, an isolating sleeve and a driven (inner) magnetic rotor, as shown in figure 1. When the magnetic driving device works, the isolation sleeve is assembled between the inner magnetic rotor and the outer magnetic rotor, so that the static seal replaces the traditional dynamic seal between the driving shaft and the driven shaft, and the non-contact transmission of torque is achieved. The cylindrical magnetic coupling realizes no mechanical connection transmission, solves the problems of overload protection, soft start, centering of a driving shaft and a driven shaft, tightness and the like in the operation and installation process, and is widely applied to the industries of pump industry, food, energy, instruments and the like.

However, the permanent magnet is an important component of the magnetic coupling, and the permanent magnet is generally made of a neodymium-iron-boron material, which has poor thermal stability and can generate demagnetization at high temperature. When the magnetic coupling is applied to occasions needing to convey high-temperature media, when the heat generated by the high temperature of the media and the eddy reaches the high-temperature demagnetization temperature of the permanent magnet, the conveying torque and efficiency of the magnetic coupling are affected, and the service life of the magnetic coupling is shortened. This limitation limits the range of applications for synchronous magnetic couplings.

In order to solve the problem, the prior art only arranges permanent magnets on an outer rotor, such as a squirrel-cage asynchronous magnetic coupling, arranges permanent magnets on the outer rotor, and uses the inner rotor as a reference for the squirrel-cage rotor of an asynchronous motor. The working principle is similar to that of a squirrel cage asynchronous motor, namely the electromagnetic induction principle. The structure is characterized in that the inner rotor is circumferentially provided with no permanent magnet, the inner rotor consists of a solid rotor matrix, an end ring and a conducting bar, and the permanent magnet is only arranged on the outer rotor in the circumferential direction, but the structure is complex, the processing is inconvenient, and the electromagnetic torque and the transmission efficiency are low.

Disclosure of Invention

In order to solve the problem, the invention provides a high-temperature-resistant cylindrical magnetic coupling.

The cylindrical magnetic coupling comprises an outer rotor, an isolation sleeve and an inner rotor, wherein a permanent magnet is arranged on the outer rotor, a groove is formed in the outer side of the inner rotor, the inner magnet is embedded into the groove, and the opening of the groove is sealed through a non-conductor material.

Preferably, the thickness ratio of the inner magnet to the non-conductor material is 2-3: 1.

Preferably, the non-conductive material is not in the same plane as the notch, and the surface of the non-conductive material is lower than the notch.

More preferably, the thicknesses of the inner magnet and the non-conductor material are 1/3-1/2 and 1/4-1/3 of the groove thickness, respectively.

Preferably, the non-conductor material is polyphenylene sulfide or heat-resistant aluminum alloy.

Preferably, the non-conductor material is a nano illite smectite clay-Glass Fiber (GF) -PPS composite material of nano illite smectite clay and Glass Fiber (GF) modified polyphenylene sulfide (PPS).

Preferably, the nano illite-GF-PPS composite material contains 5 wt.% illite clay and 30 wt.% glass fiber.

The invention uses non-conductor material to isolate high temperature medium, so the permanent magnet (inner magnet) on the inner rotor has no direct contact with the high temperature medium, and can isolate or slow down the diffusion of medium temperature, thereby reducing the influence of medium temperature on the high temperature demagnetization of the permanent magnet, therefore, the magnetic coupling has no strict requirement on the temperature of the transmission medium, and can be used in the occasion of transmitting high temperature medium.

When the action area of the permanent magnet is ensured to be unchanged, the larger the number of the permanent magnets is, the larger the thickness is, the smaller the air gap is, and the larger the eddy current loss generated by the non-conductor material is; in addition, the larger the thickness and the resistivity of the non-conductor material are, the larger the eddy current loss is under the same structural parameters. In addition, in order to sufficiently reduce the eddy current loss of the used non-conductor material, polyphenylene sulfide (PPS) is used as a base material, and modified lamellar nano illite-montmorillonite clay and Glass Fiber (GF) are added to prepare the nano illite-GF-PPS ternary composite material with low eddy current loss and excellent mechanical property. The analysis result of a universal mechanical test shows that the impact toughness of the PPS-based composite material can be obviously improved and the notch impact strength is improved by 60.2% by adding 5 wt.% of illite smectite clay (2 wt.% of epoxy resin is modified, and the fineness (100nm) is about 64 wt.%); on the basis, 30 wt.% of glass fiber is added, the tensile strength and the bending strength of the glass fiber are respectively increased by 256.3 percent and 289.2 percent compared with pure PPS, and the purposes of strengthening and toughening are achieved.

Drawings

Fig. 1 is a schematic sectional structure diagram of a conventional synchronous cylinder type magnetic coupling.

Fig. 2 is a schematic view of a partial cross-sectional structure of an inner rotor of the present invention.

1. The input shaft 2, the machine body 3, the inner magnet 3-1, the non-conductor material 4, the inner rotor 4-1, the groove 5, the output shaft 6, the isolation sleeve 7, the outer rotor 8, the outer magnet 9 and the sealing ring.

Detailed Description

In order to more clearly illustrate the invention, the invention is further described below with reference to preferred embodiments and the accompanying drawings. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention, but rather includes any combination of the specific embodiments, which is calculated by those skilled in the art from the foregoing description and any equivalent variations which are within the spirit and scope of the invention as defined by the appended claims.

As shown in fig. 1-2, a cylindrical magnetic coupling comprises an outer rotor 7, an isolation sleeve 6 and an inner rotor 4, wherein the outer rotor 7 is provided with a permanent magnet, the outer side of the inner rotor 4 is provided with a groove, the inner magnet 3 is embedded into the groove 4-1, and the opening of the groove is sealed by a non-conductor material 3-1. The thickness ratio of the inner magnet 3 to the non-conductor material 3-1 is 2-3: 1.

Preferably, the non-conductor material 3-1 is not on the same plane with the notch, and the surface of the non-conductor material 3-1 is lower than the notch. The thicknesses of the inner magnet 3 and the non-conductor material are 1/3-1/2 and 1/4-1/3 of the groove thickness respectively. The non-conductor material 3-1 is polyphenylene sulfide or heat-resistant aluminum alloy.

Claims

1. The utility model provides a drum formula magnetic coupling, includes external rotor, separation sleeve and inner rotor, is equipped with permanent magnet, its characterized in that on the external rotor: the outer side of the inner rotor is provided with a groove, the inner magnet is embedded into the groove, and the opening of the groove is sealed by a non-conductor material.

2. The cylindrical magnetic coupling of claim 1, wherein: the thickness ratio of the inner magnet to the non-conductor material is 2-3: 1.

3. The cylindrical magnetic coupling of claim 1, wherein: the non-conductor material and the notch are not on the same plane, and the surface of the non-conductor material is lower than the notch.

4. The cylindrical magnetic coupling of claim 5, wherein: the thicknesses of the inner magnet and the non-conductor material are 1/3-1/2 and 1/4-1/3 of the groove thickness respectively.

5. The cylindrical magnetic coupling of claim 1, wherein: the non-conductor material is polyphenylene sulfide or heat-resistant aluminum alloy.