Insulating material used in commutator and preparation method thereof

Abstract

The invention discloses an insulating material used in a commutator and a preparation method thereof, and relates to the technical field of insulating materials, and the insulating material comprises the following materials by weight: 300-600 parts of phenolic resin, 200-300 parts of modified epoxy resin, 400-600 parts of inorganic fiber, 150-250 parts of an inorganic filler and 100-300 parts of a composite additive. By introducing the modified epoxy resin, the high temperature resistance of the insulating material is greatly improved, and the insulating material has high mechanical strength, high heat conductivity coefficient and high insulating property, can have extremely high stability under the conditions of high temperature and high rotating speed, and avoids the conditions of deformation, cracking, short circuit and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of insulating materials, and in particular relates to an insulating material used in a commutator and a preparation method thereof. Background Art

[0002] The commutator is a key component in DC motors and some types of AC motors, which is responsible for switching the current between the rotating armature winding and the stationary external circuit. In order to ensure that the commutator can work effectively, appropriate insulating materials must be used to isolate the individual copper sheets (commutator segments), prevent short circuits, and provide the necessary electrical insulation properties. These insulating materials need to meet specific requirements, including good mechanical strength, electrical insulation, heat resistance, and stability under high speed operating conditions.

[0003] However, with the improvement of motor commutator insulation materials, under the conditions of increasing operating temperature and speed, deformation, cracking, short circuit, poor wear resistance and so on often occur. Therefore, there is an urgent need for a high temperature resistant, high strength insulation material. Summary of the invention

[0004] The purpose of the present invention is to solve the above technical problems and to provide an insulating material for use in a commutator and a preparation method and device thereof, which at least partially solve the above problems.

[0005] The technical solution adopted by the present invention is: an insulating material used in a commutator, comprising the following materials in proportion by weight: 300-600 parts of phenolic resin, 200-300 parts of modified epoxy resin, 400-600 parts of inorganic fiber, 150-250 parts of inorganic filler and 100-300 parts of composite additive.

[0006] Furthermore, the modified epoxy resin is specifically an epoxy resin with an aliphatic ring structure modified by isocyanate.

[0007] Furthermore, the inorganic fiber includes one or more of alumina whiskers, carbon fibers, boron fibers or glass fibers.

[0008] Furthermore, the inorganic filler includes one or more of active quartz powder, alumina, boron nitride, montmorillonite and calcium carbonate.

[0009] Furthermore, the composite auxiliary agent includes 60-80 parts of a curing agent, 20-40 parts of a release agent, 10-20 parts of a low-temperature accelerator, 40-60 parts of a high-temperature accelerator and 20-30 parts of an auxiliary additive.

[0010] Furthermore, the curing agent is a bio-based imidazole curing agent; and the auxiliary additive is polyethylene glycol monomethyl ether.

[0011] Furthermore, the release agent is one or more of polyethylene wax, stearic acid, zinc stearate, calcium stearate, butyl stearate, and ethylene distearate; The low temperature curing agent is a diazabicyclic modified resin, wherein the diazabicyclic is DBU8-15, and the resin is a linear phenolic resin; The high temperature accelerator is one or more of magnesium hydroxide, calcium hydroxide, zinc oxide and calcium oxide.

[0012] Furthermore, the preparation method of the low temperature accelerator comprises the following steps: Heat the phenolic resin to 120-130°C and keep it warm for 60-120 minutes; Add DBU8-15 and mix for 30-50 minutes, cool and crush through a 100-mesh sieve.

[0013] On the other hand, the present invention also proposes a method for preparing an insulating material for a commutator, comprising the following steps: Mix phenolic resin, modified epoxy resin, inorganic fiber, inorganic filler and composite additives uniformly; Add the evenly mixed powder into a heated double-roller or single-screw machine to fully melt and mix it; after cooling and crushing, the insulating material used in the commutator is obtained.

[0014] The beneficial effects of the present invention are: The present invention greatly improves the high temperature resistance of the insulating material by introducing modified epoxy resin. The insulating material has high mechanical strength, high thermal conductivity and high insulation performance, and can have extremely strong stability under high temperature and high speed conditions to avoid deformation, cracking, short circuit and the like.

[0015] The modified epoxy resin of the present invention is prepared by modifying an epoxy resin with an aliphatic ring structure by using isocyanate to obtain a modified epoxy resin with high heat resistance, low dielectric and high bonding strength. DETAILED DESCRIPTION

[0016] In order to enable those skilled in the art to better understand the present invention, the technical solution of the present invention is further described below in conjunction with embodiments.

[0017] The disclosure below provides many different embodiments or examples for implementing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numbers and / or reference letters in different examples. This repetition is for the purpose of simplicity and clarity, and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but a person of ordinary skill in the art may be aware of the application of other processes and / or the use of other materials.

[0018] The invention provides an insulating material for a commutator, comprising the following materials in proportion by weight: 300-600 parts of phenolic resin, 200-300 parts of modified epoxy resin, 400-600 parts of inorganic fiber, 150-250 parts of inorganic filler and 100-300 parts of composite auxiliary agent.

[0019] It should be noted that the introduction of modified epoxy resin greatly improves the high temperature resistance of the insulating material, and makes the insulating material have high mechanical strength, high thermal conductivity and high insulation performance, so that the insulating material can have strong stability under high temperature and high speed conditions, avoiding deformation, cracking, short circuit and the like.

[0020] In a further implementation of this embodiment, the modified epoxy resin is specifically an epoxy resin with an aliphatic ring structure modified by isocyanate.

[0021] It should be noted that the modified epoxy resin obtained by modifying the epoxy resin with a fat-exchange structure with isocyanate has good adhesive strength and high glass transition temperature of the cured product. In addition, the epoxy resin composition containing the epoxy resin of the present invention and the flame retardant also shows good flame retardancy in addition to these properties. In addition, the dielectric properties are also excellent, and good properties are exerted in laminated boards and electronic circuit substrates requiring low dielectric constants and low dielectric loss tangents.

[0022] In a further implementation of this example, the inorganic fiber includes one or more of alumina whiskers, carbon fibers, boron fibers or glass fibers.

[0023] It should be noted that the length of the inorganic fiber is 3 mm and the average diameter is 12 um; adding micron-sized alumina whiskers or other types of reinforcing fibers can not only significantly improve the mechanical strength of the insulating part, but also maintain good flexibility and processing performance.

[0024] In a further implementation of this example, the inorganic filler includes one or more of active quartz powder, alumina, boron nitride, montmorillonite and calcium carbonate.

[0025] It should be noted that the particle size of boron nitride is 5-14μm, and the particle size of other inorganic fillers is 15nm. Adding the above inorganic fillers can effectively improve the insulation performance of the product. It can also greatly improve the thermal conductivity of the product, so that the thermal conductivity of the product can reach 1.2830 W / (m·K), which is 756% higher than that of pure epoxy resin, and it shows good tolerance performance under high-frequency and high-voltage electric fields.

[0026] In a further implementation of this example, the composite auxiliary agent includes 60-80 parts of a curing agent, 20-40 parts of a release agent, 10-20 parts of a low-temperature accelerator, 40-60 parts of a high-temperature accelerator, and 20-30 parts of an auxiliary additive.

[0027] In a further implementation of this example, the curing agent is a bio-based imidazole curing agent; and the auxiliary additive is polyethylene glycol monomethyl ether.

[0028] It should be noted that the glass transition temperature, mechanical strength and corrosion resistance of the cured epoxy thermosetting resin can be significantly improved by using bio-based imidazole curing agents without sacrificing other properties.

[0029] The addition of polyethylene glycol monomethyl ether not only helps to improve the aging resistance and high temperature resistance of the product, but also can reduce the cost of the material to a certain extent.

[0030] In a further embodiment of this embodiment, the release agent is one or more of polyethylene wax, stearic acid, zinc stearate, calcium stearate, butyl stearate, and ethylene distearate; The low temperature curing agent is a diazabicyclic modified resin, wherein the diazabicyclic is DBU8-15, and the resin is a linear phenolic resin; The high temperature accelerator is one or more of magnesium hydroxide, calcium hydroxide, zinc oxide and calcium oxide.

[0031] In a further embodiment of this example, the preparation method of the low temperature accelerator comprises the following steps: Heat the phenolic resin to 120-130°C and keep it warm for 60-120 minutes; Add DBU8-15 and mix for 30-50 minutes, cool and crush through a 100-mesh sieve.

[0032] It should be noted that the diazabicyclic modified resin is a colorless or light yellow liquid and is a sterically hindered amidine. The diazabicyclic modified resin has low-temperature catalytic properties, and the material after reaction with the resin has good dimensional stability, moisture and heat resistance and high pressure cooking performance.

[0033] On the other hand, the present invention also proposes a method for preparing an insulating material for a commutator, comprising the following steps: Mix phenolic resin, modified epoxy resin, inorganic fiber, inorganic filler and composite additives uniformly; Add the evenly mixed powder into a heated double-roll or single-screw machine to fully melt and mix it; after cooling and crushing, the insulating material used in the commutator is obtained.

[0034] The present invention is further explained below through several specific embodiments, which are only for illustration and are not intended to be limiting. Example 1 Heat the phenolic resin to 120-130°C and keep it warm for 60-120 minutes; add DBU8-15 and mix for 30-50 minutes, cool and crush through a 100-mesh sieve to obtain a diazabicyclic modified resin.

[0035] Mix 300 parts of phenolic resin, 200 parts of modified epoxy resin, 400 parts of inorganic fiber, 150 parts of inorganic filler, 60 parts of curing agent, 20 parts of release agent, 10 parts of low temperature accelerator, 40 parts of high temperature accelerator and 20 parts of auxiliary additives; Add the evenly mixed powder into a heated double-roll or single-screw machine to fully melt and mix it; after cooling and crushing, the insulating material used in the commutator is obtained.

[0036] Example 2 Heat the phenolic resin to 120-130°C and keep it warm for 60-120 minutes; add DBU8-15 and mix for 30-50 minutes, cool and crush through a 100-mesh sieve to obtain a diazabicyclic modified resin.

[0037] Mix 400 parts of phenolic resin, 220 parts of modified epoxy resin, 450 parts of inorganic fiber, 170 parts of inorganic filler, 64 parts of curing agent, 24 parts of release agent, 12 parts of low temperature accelerator, 44 parts of high temperature accelerator and 22 parts of auxiliary additives; Add the evenly mixed powder into a heated double-roll or single-screw machine to fully melt and mix it; after cooling and crushing, the insulating material used in the commutator is obtained.

[0038] Example 3 Heat the phenolic resin to 120-130°C and keep it warm for 60-120 minutes; add DBU8-15 and mix for 30-50 minutes, cool and crush through a 100-mesh sieve to obtain a diazabicyclic modified resin.

[0039] Mix 450 parts of phenolic resin, 240 parts of modified epoxy resin, 480 parts of inorganic fiber, 190 parts of inorganic filler, 68 parts of curing agent, 28 parts of release agent, 14 parts of low temperature accelerator, 48 parts of high temperature accelerator and 24 parts of auxiliary additives; Add the evenly mixed powder into a heated double-roll or single-screw machine to fully melt and mix it; after cooling and crushing, the insulating material used in the commutator is obtained.

[0040] Example 4 Heat the phenolic resin to 120-130°C and keep it warm for 60-120 minutes; add DBU8-15 and mix for 30-50 minutes, cool and crush through a 100-mesh sieve to obtain a diazabicyclic modified resin.

[0041] Mix 500 parts of phenolic resin, 260 parts of modified epoxy resin, 520 parts of inorganic fiber, 210 parts of inorganic filler, 72 parts of curing agent, 32 parts of release agent, 16 parts of low temperature accelerator, 52 parts of high temperature accelerator and 26 parts of auxiliary additives; Add the evenly mixed powder into a heated double-roll or single-screw machine to fully melt and mix it; after cooling and crushing, the insulating material used in the commutator is obtained.

[0042] Example 5 Heat the phenolic resin to 120-130°C and keep it warm for 60-120 minutes; add DBU8-15 and mix for 30-50 minutes, cool and crush through a 100-mesh sieve to obtain a diazabicyclic modified resin.

[0043] Mix 550 parts of phenolic resin, 280 parts of modified epoxy resin, 560 parts of inorganic fiber, 230 parts of inorganic filler, 76 parts of curing agent, 36 parts of release agent, 18 parts of low temperature accelerator, 56 parts of high temperature accelerator and 28 parts of auxiliary additives; Add the evenly mixed powder into a heated double-roll or single-screw machine to fully melt and mix it; after cooling and crushing, the insulating material used in the commutator is obtained.

[0044] Example 6 Heat the phenolic resin to 120-130°C and keep it warm for 60-120 minutes; add DBU8-15 and mix for 30-50 minutes, cool and crush through a 100-mesh sieve to obtain a diazabicyclic modified resin.

[0045] Mix 600 parts of phenolic resin, 300 parts of modified epoxy resin, 600 parts of inorganic fiber, 250 parts of inorganic filler, 80 parts of curing agent, 40 parts of release agent, 20 parts of low temperature accelerator, 60 parts of high temperature accelerator and 30 parts of auxiliary additives; Add the evenly mixed powder into a heated double-roller or single-screw machine to fully melt and mix it; after cooling and crushing, the insulating material used in the commutator is obtained.

[0046] The insulating materials prepared in the above-mentioned Examples 1 to 6 were tested respectively, and the performance data results are shown in Table 1 below: Table 1

[0047] The above are only embodiments of the present invention. The common knowledge such as the known specific structures and characteristics in the scheme is not described in detail here. Ordinary technicians in the relevant field are aware of all the common technical knowledge in the technical field to which the invention belongs before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply conventional experimental means before that date. Ordinary technicians in the relevant field can improve and implement the scheme in combination with their own abilities under the inspiration given by this application. Some typical known structures or methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for technicians in this field, without departing from the structure of the present invention, they can also make several deformations and improvements, which should also be regarded as the scope of protection of the present invention. These will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. An insulating material used in a commutator, characterized in that: The invention comprises the following materials in proportion by weight: 300-600 parts of phenolic resin, 200-300 parts of modified epoxy resin, 400-600 parts of inorganic fiber, 150-250 parts of inorganic filler and 100-300 parts of composite auxiliary agent.

2. The insulating material for commutator according to claim 1, characterized in that: The modified epoxy resin is specifically an epoxy resin with an aliphatic ring structure that is modified by isocyanate.

3. The insulating material for commutator according to claim 1, characterized in that: The inorganic fibers include one or more of alumina whiskers, carbon fibers, boron fibers or glass fibers.

4. The insulating material for commutator according to claim 1, characterized in that: The inorganic filler includes one or more of active quartz powder, alumina, boron nitride, montmorillonite and calcium carbonate.

5. The insulating material for commutator according to claim 1, characterized in that: The composite auxiliary agent comprises 60-80 parts of a curing agent, 20-40 parts of a release agent, 10-20 parts of a low-temperature accelerator, 40-60 parts of a high-temperature accelerator and 20-30 parts of an auxiliary additive.

6. The insulating material for commutator according to claim 5, characterized in that: The curing agent is a bio-based imidazole curing agent; the auxiliary additive is polyethylene glycol monomethyl ether.

7. The insulating material for commutator according to claim 5, characterized in that: The release agent is one or more of polyethylene wax, stearic acid, zinc stearate, calcium stearate, butyl stearate, and ethylene distearate; The low temperature curing agent is a diazabicyclic modified resin, wherein the diazabicyclic is DBU8-15, and the resin is a linear phenolic resin; The high temperature accelerator is one or more of magnesium hydroxide, calcium hydroxide, zinc oxide and calcium oxide.

8. The insulating material for commutator according to claim 7, characterized in that: The preparation method of the low temperature accelerator comprises the following steps: Heat the phenolic resin to 120-130°C and keep it warm for 60-120 minutes; Add DBU8-15 and mix for 30-50 minutes, cool and crush through a 100-mesh sieve.

9. A method for preparing an insulating material for a commutator, characterized in that: The following steps are involved: Mix phenolic resin, modified epoxy resin, inorganic fiber, inorganic filler and composite additives uniformly; Add the evenly mixed powder into a heated double-roller or single-screw machine to fully melt and mix it; after cooling and crushing, the insulating material used in the commutator is obtained.

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