New energy automobile motor protective cover and preparation method

Abstract

The application belongs to the technical field of motor protective cover and specifically relates to a new energy automobile motor protective cover and a preparation method, which comprises a cover body of the protective cover, the cover body comprises an outer protective layer, an inner protective layer and a heat insulating body between the outer protective layer and the inner protective layer, the heat insulating body is composed of a plurality of fiber layers stacked and pressed, the fiber layer comprises a fiber framework of a three-dimensional warp-weft weaving structure and a filler filled in the fiber framework, the filler comprises 50-70 parts of basalt fiber, 15-25 parts of aerogel powder and 2-8 parts of talc powder in terms of mass ratio, has good mechanical properties, is not easy to deform under the action of external force, has high temperature resistance, and the heat preservation effect is significantly enhanced, thereby meeting the protection requirements on the motor.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of motor protective cover and specifically relates to a new energy automobile motor protective cover and a preparation method. BACKGROUND

[0002] The motor is a core component of the new energy automobile, in order to improve the safety thereof, a protective cover is arranged outside the motor cover, so as to avoid the direct exposure of the motor, avoid the adhesion of dust and impurities on the surface of the motor, and affect the use of the motor. With the continuous development of the new energy automobile, the requirement for the safety thereof is also higher and higher, the circuit structure, battery management system and the like on the new energy automobile are complex and various, in order to cope with potential risks, higher requirements are put forward for the motor protective cover, and the motor protective cover is required to have heat insulation and heat preservation capacity, and is required to have high temperature resistance.

[0003] The existing protective cover is generally made of fiber felt and has heat insulation and heat preservation capacity, but the structure thereof is simple, the mechanical property is poor, and after long time use or after being impacted by external force, the protective cover is deformed or even damaged, so that the heat insulation and heat preservation functions thereof are lost, once a fire occurs, the safety of the motor cannot be guaranteed, the loss is increased, and the high temperature resistance and weather resistance of the existing protective cover also need to be improved. SUMMARY

[0004] The application aims to solve the above-mentioned defects, provide a new energy automobile motor protective cover and a preparation method, have good mechanical property, are not easy to be deformed under the action of external force, have significantly enhanced high temperature resistance and heat preservation effect, and meet the protection requirements for the motor.

[0005] The application solves the technical problems thereof by adopting the following technical solutions:

[0006] The new energy automobile motor protective cover comprises a cover body of the protective cover, the cover body comprises an outer protective layer, an inner protective layer and a heat insulation body between the outer protective layer and the inner protective layer, the heat insulation body is composed of a plurality of fiber layers stacked and pressed, the fiber layer comprises a fiber framework of a three-dimensional warp-weft woven structure and a filler filled in the fiber framework, the filler comprises 50-70 parts of basalt fiber, 15-25 parts of aerogel powder, 2-8 parts of talc powder and 10-15 parts of mica powder in terms of mass ratio, and the distribution density of the mica powder in the heat insulation body decreases from outside to inside.

[0007] Further, the fiber framework is formed by three-dimensional warp-weft weaving of PBI fiber, the fiber framework comprises an upper surface layer, a lower surface layer and connecting fibers connecting the upper surface layer and the lower surface layer, the connecting fibers are connected by cross connection of the upper surface layer and the lower surface layer in a stringing mode to form a curved intermediate layer, and the upper surface layer and the lower surface layer are at least two layers.

[0008] Further, the filler further comprises 0.2-0.4 parts of surfactant, 0.1-0.5 parts of coupling agent by mass ratio.

[0009] Further, the outer protective layer and the inner protective layer are both PET non-woven fabric layers, and the outer protective layer comprises 60-80 parts of polyester chips, 3-8 parts of intumescent flame retardant and 0.3-0.8 parts of KH550 by mass ratio.

[0010] Further, the surfactant is sodium dodecyl benzene sulfonate, and the coupling agent is KH560.

[0011] Further, the filler further comprises 0.5-2 parts of adhesive by mass ratio, and the adhesive is a mixture of one or more of phenolic resin, polyvinyl acetate and acrylic ester in any proportion.

[0012] Further, the inner side of the cover body is provided with a metal mesh layer, and the structure of the metal mesh layer and the cover body is consistent with the external structure of the motor.

[0013] The preparation method of the new energy automobile motor protective cover comprises the following steps:

[0014] S1: forming a thermal insulation body;

[0015] Step a. A three-dimensional warp-knitted structure fiber skeleton is prepared by warp-knitting PBI fibers using warp-knitting equipment, wherein the outer surface layer and the inner surface layer of the fiber skeleton are both two layers, and the thickness of the middle layer is not less than 1mm;

[0016] Step b. 50-70 parts of basalt fibers, 15-25 parts of aerogel powder, 2-8 parts of talcum powder, 0.2-0.4 parts of sodium dodecyl benzene sulfonate, 0.1-0.5 parts of KH560 and 10-15 parts of mica powder are prepared by mass ratio;

[0017] Step c. The KH560 is divided into two parts, half of the KH560, mica powder and aerogel powder are first put into a beater, steam is introduced into the beater to raise the temperature to 85℃, the beater rotates at a speed of 50-100r / min, and the beating is carried out for 5-10min, then sodium dodecyl benzene sulfonate, crushed basalt fibers are added into the beater, the temperature is raised to 95℃, the beater rotates at a speed of 100-130r / min, and the beating is carried out for 10-15min, and then the adhesive, talcum powder and the other half of the KH560 are added into the beater, and the beater rotates at a speed of 150-200r / min, and the beating is carried out for 5-10min.

[0018] Step d. The mixed slurry obtained in step c is placed in a slurry tank of a wet forming device, and the fiber skeleton prepared in step a is placed on a forming net of the wet forming device, the fiber skeleton being in a taut state on the forming net, and the mixed slurry in the slurry tank is formed in the fiber skeleton through a cloth mechanism to obtain a fiber layer;

[0019] Step e. The content of the mica powder in step b is adjusted to obtain fiber layers with different contents of mica powder according to step d;

[0020] Step f. The multiple fiber layers obtained in step d are placed in a heat insulation body forming mold, and an adhesive is sprayed between the adjacent two fiber layers, the content of the mica powder in the fiber layers decreases from top to bottom, and then the heat insulation body is obtained by hot pressing;

[0021] S2: Forming the outer protective layer and the inner protective layer;

[0022] In the process of forming the heat insulation body, the outer protective layer and the inner protective layer can be formed synchronously, and the forming of the outer protective layer is as follows:

[0023] Step g. Prepare 60-80 parts of polyester chips, 3-8 parts of intumescent flame retardant, and 0.3-0.8 parts of KH550 according to the mass ratio;

[0024] Step h. Add the PET polyester chips, the intumescent flame retardant, and the KH550 into an extruder, melt extrude, and prepare PET granules. After drying the PET granules, they are sent to a spinning box through a melt filter, a spinning metering pump, and then spun. After spinning, a web is formed and hot rolled to obtain the outer protective layer;

[0025] S3: Cover body forming;

[0026] The inner protective layer, the heat insulation body, and the outer protective layer are sequentially laminated and placed in a composite mold for composite forming to obtain a cover body.

[0027] The application has the beneficial effects that: by the above scheme, the fiber layer with the three-dimensional warp-knitted structure has the characteristics of high density and high weather resistance, has strong heat insulation and heat preservation capacity, and has strong deformation resistance, and the post-impact structure is not easy to be damaged or has small damage degree, and the heat insulation and heat preservation capacity is not damaged, the heat insulation and heat preservation performance of the heat insulation body composed of the laminated and stacked fiber layers is excellent, the heat insulation body has a heat insulation thermal conductivity of 0.001 W / (m*K), reaches the level of heat insulation materials, has strong heat insulation and heat preservation capacity in high-temperature environment, and the mechanical performance of the heat insulation body is stable and reliable, the protective cover with the "sandwich" structure is formed by the PET outer protective layer, the inner protective layer and the heat insulation body, has excellent waterproof, heat insulation, heat preservation and sound insulation effects, and the use effect is remarkable, the metal mesh layer is used as the framework on the inner side of the protective cover, and the mechanical performance of the protective cover is further enhanced, the structure is stable, is suitable for use of the new energy automobile motor protective cover, has high compatibility with the motor, avoids that the protective cover is pasted on the surface of the motor and "sticks" the motor, plays the heat insulation and heat preservation while avoiding affecting heat dissipation of the motor, when impacted by external force, the mechanical performance of the protective cover is strong, is not easy to deform or has small deformation degree, the heat insulation and heat preservation capacity is slightly damaged, meanwhile, the heat preservation capacity in cold environment is strong, the motor is kept in a suitable starting environment, the energy consumption and starting difficulty of the motor are reduced, the motor has good protection, the preparation process is simple, the existing equipment does not need to be improved too much, and the production investment is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0028] The foregoing and other objects, features and advantages of the application will become apparent upon reading the following detailed description of the application on combined with reference to the accompanying drawings.

[0029] Figure 1 The structure schematic view of one embodiment of the application.

[0030] Figure 2 The partial cross-sectional schematic view of the cover body in one embodiment of the application.

[0031] Figure 3 The cross-sectional schematic view of one embodiment of the application.

[0032] Figure 4 The cross-sectional schematic view of the fiber framework in one embodiment of the application.

[0033] Figure 5 The cross-sectional schematic view of the fiber layer in one embodiment of the application.

[0034] 1, cover body; 11, outer protective layer; 12, inner protective layer; 13, heat insulation body; 14, fiber layer; 15, fiber framework; 151, upper surface layer; 152, lower surface layer; 153, middle layer, 16, filler;

[0035] 2, metal mesh layer; 21, protrusion. DETAILED DESCRIPTION

[0036] The application will be further described below with reference to the accompanying drawings.

[0037] Embodiment 1: A heat insulation body for a new energy automobile motor protective cover, referring to Figure 3 The heat insulation body 13 is composed of a plurality of fiber layers 14 laminated, referring to Figure 5 The fiber layer 14 includes a three-dimensional warp-weft woven structure fiber framework 15, a heat insulation and heat preservation filler 16 filled in the fiber framework 15, the filler 16 includes basalt fiber 50 parts, aerogel powder 15 parts, talcum powder 2 parts, mica powder 15 parts, adhesive 0.5 parts, sodium dodecyl benzene sulfonate 0.2 parts, KH560 0.1 parts by mass ratio, the fiber framework 15 is formed by three-dimensional warp-weft weaving of PBI fiber, referring to Figure 4 The fiber framework 15 includes an upper surface layer 151, a lower surface layer 152 and a connecting fiber connecting the upper surface layer 151 and the lower surface layer 152, the connecting fiber is connected by cross connecting through the stringing of the upper surface layer 151 and the lower surface layer 152 to form a curved middle layer 153, as a preferred embodiment, the upper surface layer 151 and the lower surface layer 152 are both two layers.

[0038] The preparation method of the above heat insulation body:

[0039] a. The PBI fiber is three-dimensionally woven by using warp knitting equipment, the outer surface layer, the inner surface layer and the middle layer 153 of the warp-weft woven fiber framework, the connecting fiber is cross connected by stringing the upper surface layer and the lower surface layer to form a curved middle layer 153, during weaving, the outer surface layer and the inner surface layer are both woven for two layers, the longitudinal interval between the outer surface layer and the inner surface layer is 1mm, i.e. the thickness of the middle layer 153 is 1mm, to obtain the three-dimensional warp knitting structure fiber framework for standby;

[0040] b. basalt fiber 50 parts, aerogel powder 15 parts, talcum powder 2 parts, sodium dodecyl benzene sulfonate 0.2 parts, KH560 0.1 parts, adhesive 0.5 parts, mica powder 15 parts by mass ratio, the adhesive is a mixture of one or several of phenolic resin, polyvinyl acetate and acrylic ester in any proportion;

[0041] c. To the beater, add water 100 parts (by mass), add KH560 in two parts, first add half of the KH560, mica powder, aerogel powder into the beater, introduce steam into the beater, raise the temperature to 85℃, keep the beater speed at 80r / min, beat for 5min, then add sodium dodecyl benzene sulfonate, sheared and crushed basalt fiber into the beater, raise the temperature to 95℃, the beater speed is 120r / min, beat for 15min, then add the adhesive, talc, the other half of the KH560 into the beater, the beater speed is raised to 200r / min, beat for 10min, get the fiber mixed slurry, introduce steam, the temperature is maintained at 85℃, the coupling agent and aerogel powder are quickly mixed to improve the interface ability of the aerogel powder, when the basalt fiber is added, the temperature is raised again, the steam continues to be introduced, which has the effect of "bubble stirring" during the process, increasing the mixing and adhesion of basalt fiber and aerogel powder, improving the dispersion, the addition of talc makes the three materials mix and composite uniformly in the appropriate speed range, the adhesive enhances the bonding strength between materials, improves the compactness and structural stability of the fiber layer after forming;

[0042] d. Put the fiber mixed slurry obtained in step c) into the slurry tank of the wet forming equipment, place the fiber skeleton prepared in step a) on the forming net of the wet forming equipment, and make the fiber skeleton in the stretched and tightened state on the forming net by tightening the equipment with the tightening clamp, the upper and lower layers of the fiber skeleton are separated, and the fiber mixed slurry in the slurry tank is distributed in the fiber skeleton by the distribution mechanism, the fiber mixed slurry is evenly attached to the three-dimensional structure of the fiber skeleton, and the fiber layer is obtained after treatment such as suction and drying, the fiber mixed slurry is easily attached and formed in the three-dimensional structure of the fiber skeleton to form a fiber layer, and due to the presence of the adhesive, the structural strength of the fiber mixed slurry and the fiber skeleton is good, after suction and drying, most of the water is discharged, and the adhesive fully plays its adhesive effect, making the fiber layer form stably and the structure dense;

[0043] e. Adjust the content of mica powder in step b, and obtain fiber layers with different contents of mica powder according to step d;

[0044] f. Place the fiber layers obtained in step d) in multiple layers in the heat insulation body forming mold, spray adhesive between the adjacent two layers of fiber layers, the content of mica powder in the fiber layer decreases from top to bottom, then heat press to obtain a multi-layer structure of the heat insulation body, and the structure of the heat insulation body after spraying adhesive again is more stable and not easy to delaminate, improving its structural performance.

[0045] The filler in the heat insulator is mainly basalt fiber, mixed aerogel powder is used as primary filling, the aerogel powder and the basalt fiber adhere to each other to form a composite heat insulation mixture, and then talcum powder is added for secondary filling. Under the promotion of the auxiliary agent, the three are combined, and all of them are heat insulation materials. The aerogel has excellent heat insulation and heat preservation performance. After the gaps in the mixture are filled with the aerogel powder and the talcum powder, the mixture becomes more compact, and the density is increased again. A composite heat insulation filling body with a compact structure is obtained. The addition of the talcum powder not only makes the composite heat insulation filling body more compact, but also improves the adhesion between the materials through the interaction with the auxiliary agent. Especially under the action of heat pressing and the promotion of the adhesive, the talcum powder forms a filler skeleton in the fiber layer. The filler skeleton is combined with the fiber skeleton to greatly improve the rigidity and stability of the composite heat insulation filling body, and to enhance the tensile strength and shear strength. The impact resistance of the obtained fiber layer is significantly enhanced. The filler is filled into the three-dimensional fiber skeleton to form a three-dimensional and compact fiber layer. The fiber layer has stable structure and good mechanical properties, and heat is difficult to penetrate. The thermal conductivity of the heat insulator 13 is 0.001 W / (m·K), which belongs to heat insulation material. The heat insulation, heat insulation and heat preservation performance is remarkable. The multilayer three-dimensional fiber layer is stacked to form the heat insulator 13. The mechanical properties of the single-layer fiber layer are stable due to its three-dimensional structure, and it is not easy to deform. After stacking multiple layers, the structure of the obtained heat insulator 13 is not only compact and has high density, but also its mechanical properties are improved again. The heat insulator 13 has strong anti-deformation ability and is not easy to deform. Even under the action of external impact, the heat insulator still maintains a stable structure and will not be torn or faulted. The heat insulator has strong impact resistance and anti-deformation ability, strong weather resistance in high temperature environment, and is not easy to deform in high temperature environment for a long time. The heat insulator fully plays its role of compact structure, temperature insulation, heat insulation and heat preservation. The addition of talcum powder and mica powder improves the heat insulation and fire resistance. The distribution density of mica powder in the heat insulator can improve the fire resistance of the heat insulator 13 and enhance its ability to resist external high temperature and burning environment. The use performance of the heat insulator 13 is significantly improved. Of course, the distribution density of mica powder can be adjusted to meet the use requirements. The heat insulation and high temperature resistance performance of the heat insulator is excellent, and has wide application prospect.

[0046] Embodiment 2: A heat insulator for a new energy automobile motor protective cover, referring to Figure 3 The heat insulator 13 is composed of a plurality of fiber layers 14 stacked together, referring to Figure 5 The fiber layer 14 includes a three-dimensional warp and weft woven structure fiber skeleton 15 and a heat insulation and heat preservation filler 16 filled in the fiber skeleton 15. The fiber skeleton 15 is formed by three-dimensional warp and weft weaving of PBI fiber, referring to Figure 4The fiber framework 15 includes an upper surface layer 151, a lower surface layer 152, and connecting fibers connecting the upper surface layer 151 and the lower surface layer 152, the connecting fibers cross-connect by threading the upper surface layer 151 and the lower surface layer 152 to form a curved intermediate layer 153, as a preferred embodiment, the upper surface layer 151 and the lower surface layer 152 are both two layers, wherein the filler 16 includes basalt fiber 60 parts, aerogel powder 20 parts, talc powder 5 parts, mica powder 10 parts, adhesive 1 part, sodium dodecyl benzene sulfonate 0.3 parts, KH560 0.3 parts by mass ratio.

[0047] Embodiment 3: A heat insulating body for a new energy automobile motor protective cover, referring to Figure 3 The heat insulating body 13 is composed of a plurality of fiber layers 14 laminated, referring to Figure 5 The fiber layer 14 includes a fiber framework 15 with a three-dimensional warp-weft weaving structure, and a heat-insulating and heat-preservation filler 16 filled in the fiber framework 15, the fiber framework 15 is formed by three-dimensional warp-weft weaving of PBI fiber, referring to Figure 4 The fiber framework 15 includes an upper surface layer 151, a lower surface layer 152, and connecting fibers connecting the upper surface layer 151 and the lower surface layer 152, the connecting fibers cross-connect by threading the upper surface layer 151 and the lower surface layer 152 to form a curved intermediate layer 153, as a preferred embodiment, the upper surface layer 151 and the lower surface layer 152 are both two layers, wherein the filler 16 includes basalt fiber 60 parts, aerogel powder 20 parts, talc powder 5 parts, mica powder 10 parts, adhesive 1 part, sodium dodecyl benzene sulfonate 0.3 parts, KH560 0.3 parts by mass ratio.

[0048] Part of the samples of the heat insulating body for a new energy automobile motor protective cover prepared in Embodiments 1-3 were taken for thermal conductivity detection, the sample size was 300mm*300mm, the protection flat plate method was adopted, and the detection was carried out according to the GB / T10294 standard, and the detection results are shown in Table 1:

[0049] Item Specification Thermal conductivity Example 1 300*300 (mm) 0.018 W / (m-K) Example 2 300*300 (mm) 0.021 W / (m-K) Example 3 300*300 (mm) 0.019 W / (m-K)

[0050] According to Table 1, the heat insulating body for a new energy automobile motor protective cover prepared in Embodiments 1-3 belongs to heat-insulating material, and has low thermal conductivity.

[0051] According to the GB / T20310 standard, part of the samples of the heat insulating body for a new energy automobile motor protective cover prepared in Embodiments 1-3 were taken for tear resistance detection, and the detection results are shown in Table 2:

[0052] Item Longitudinal tensile strength Transverse tensile strength Elongation at break Example 1 751-823N 751-823N 2.4％ Example 2 743-799N 743-799N 2.7％ Example 3 762-851N 762-851N 2.5％

[0053] According to Table 2, the heat insulating body for a new energy automobile motor protective cover prepared in Embodiments 1-3 has high longitudinal strength and transverse strength, and has good tear resistance.

[0054] Embodiment 4: a non-woven fabric for a new energy automobile motor protective cover, comprising polyester chips 60 parts, intumescent flame retardant 3 parts, KH550 0.3 parts by mass ratio.

[0055] The preparation of the non-woven fabric for the new energy automobile motor protective cover comprises:

[0056] f. Prepare polyester chips 60 parts, intumescent flame retardant 3 parts, KH550 0.3 parts by mass ratio;

[0057] g. Add PET polyester chips, intumescent flame retardant and KH550 into the extruder, melt extrude, and prepare PET granules. After drying the PET granules, pass through a melt filter, a spinning metering pump, and then send them to a spinning box for spinning. After spinning, perform webbing hot rolling to obtain a flame-retardant non-woven fabric. When it burns, the non-woven fabric will carbonize to form a flame-retardant layer, playing a heat insulation role.

[0058] Embodiment 5: a non-woven fabric for a new energy automobile motor protective cover, comprising polyester chips 80 parts, intumescent flame retardant 8 parts, KH550 0.8 parts by mass ratio.

[0059] The new energy automobile motor protective cover, referring to Figure 1 , Figure 2 , comprises a cover body 1 of the protective cover, a metal mesh layer 2 is arranged on the inner side of the cover body 1, the structure of the metal mesh layer 2 and the cover body 1 is consistent with the external structure of the motor 1, a plurality of protrusions 21 are arranged on the outer surface of the metal mesh layer 2 close to the cover body 1, the protrusions 21 penetrate into the cover body 1, improving the connection strength of the two, the metal mesh layer 2 is bonded to the cover body 1 through an adhesive and is formed by hot-pressing bonding, the metal mesh layer 2 is additionally arranged on the inner side, improving the structural rigidity of the protective cover, making the structure of the protective cover more stable, the gap between the surface of the protective cover and the motor can be maintained, the protective cover will not "stick" to the outer surface of the motor, avoiding adverse effects on the heat dissipation of the motor, and promoting the heat dissipation efficiency of the motor. When the external part of the motor is at high temperature, the metal mesh layer 2 can keep the structure of the protective cover from deforming, enhancing its high-temperature resistance and fire resistance, improving the use performance, the metal mesh layer 2 is light in quality, realizing lightweight, a plurality of windows are arranged on the cover body 1, and a hollow structure is arranged at the metal mesh layer 2, facilitating the arrangement of other components connected with the motor, such as heat dissipation or other electrical elements.

[0060] The cover body 1 comprises an outer protective layer 11, an inner protective layer 12, and a heat insulation body 13 between the outer protective layer 11 and the inner protective layer 12, the heat insulation body 13 is composed of a plurality of fiber layers 14 laminated, the fiber layer 14 comprises a fiber skeleton 15 with a three-dimensional warp-knitted structure, and a heat-insulating and heat-preserving filler 16 filled in the fiber skeleton 15, the fiber skeleton 15 is formed by three-dimensional warp-knitting of PBI fibers, the fiber skeleton 15 comprises an upper surface layer 151, a lower surface layer 152, and connecting fibers connecting the upper surface layer 151 and the lower surface layer 152, the connecting fibers cross-connect to form a curved intermediate layer 153 by threading the upper surface layer 151 and the lower surface layer 152, as a preferred embodiment, the upper surface layer 151 and the lower surface layer 152 are at least two layers, the PBI fibers have good high-temperature resistance, and the fiber skeleton 15 with a three-dimensional structure is woven by using the PBI fibers to firmly fix the filler 16 in the fiber skeleton 1, on the one hand, the structure is improved in compactness and density, the basalt fibers are combined compactly, the heat insulation and heat preservation effect is significantly enhanced, the fiber layer has excellent heat insulation and heat preservation effect, on the other hand, the structural stability of the fiber layer 14 is improved, the mechanical properties are improved, the fiber layer 14 is not prone to loosening, has strong impact resistance, and weather resistance is significantly improved, after the fiber layer is subjected to external force, the three-dimensional warp-knitted structure of the fiber layer can resist impact and disperse stress, reduce and avoid damage to the structure of the fiber layer, avoid damage to the heat insulation and heat preservation capacity, and has wide application prospect.

[0061] The outer protective layer 11 and the inner protective layer 12 adopt PET non-woven fabric layers, and the non-woven fabric of the outer protective layer 11 has a greater grammage than the non-woven fabric of the inner protective layer 12, as a preferred embodiment, the grammage of the outer protective layer 11 is twice the grammage of the non-woven fabric of the inner protective layer 12, a hydrophobic layer is formed on both sides of the heat insulation body 13, the hydrophobic and water-blocking layer protects the cover from water vapor invasion, enhances weather resistance, and prolongs service life, the inner protective layer 12 has a small grammage, can improve the sound insulation and noise reduction effect of the motor operation noise, impact and consume part of the noise energy, and after the noise energy penetrates the inner protective layer 12, the noise energy is consumed by the inner protective layer 12, and after penetration, the noise energy is blocked and consumed by the heat insulation body, the outer protective layer 11 has a large grammage and a dense structure, effectively avoids leakage of part of residual noise, at the same time, the outer layer has stronger hydrophobicity, improves water resistance, meets the use requirements of new energy automobile motor heat insulation and heat preservation, and is sufficient to cope with the motor protection and heat preservation requirements of new energy automobile in accidental fire and cold climate.

[0062] The preparation method of the new energy automobile motor protective cover comprises the following steps:

[0063] S1: preparing a heat insulation body

[0064] The PBI fiber is three-dimensionally woven by using warp knitting equipment, the outer surface layer and the inner surface layer of the warp-knitted fiber framework, the intermediate layer 153, the upper surface layer and the lower surface layer of the connected fiber string, and the cross-connection of the upper surface layer and the lower surface layer to form the curved intermediate layer 153. During weaving, the outer surface layer and the inner surface layer are both woven in two layers, the longitudinal spacing between the outer surface layer and the inner surface layer is 1 mm, that is, the thickness of the intermediate layer 153 is 1 mm, and the fiber framework with three-dimensional warp-knitting structure is obtained. According to the mass ratio, basalt fiber 50 parts, aerogel powder 15 parts, talcum powder 2 parts, mica powder 15 parts, sodium dodecyl benzene sulfonate 0.2 parts, KH560 0.1 parts, and adhesive 0.5 parts are prepared. Water 100 parts (by mass) is added to the beater. KH560 is divided into two parts. First, half of the KH560, mica powder, and aerogel powder are added to the beater. Steam is introduced into the beater to raise the temperature to 85℃. The beater speed is maintained at 80r / min. Beating is performed for 5 minutes. Then, sodium dodecyl benzene sulfonate, and sheared and crushed basalt fiber are added to the beater. The temperature is raised to 95℃. The beater speed is 120r / min. Beating is performed for 15 minutes. Then, adhesive, talcum powder, and the other half of the KH560 are added to the beater. The beater speed is increased to 200r / min. Beating is performed for 10 minutes. A fiber mixed slurry is obtained. The fiber mixed slurry is placed in a slurry tank of a wet forming device. The fiber framework is placed on a forming net of the wet forming device. The fiber framework is in a stretched and tightened state on the forming net by a tensioning clamp. The upper surface layer and the lower surface layer of the fiber framework are separated. The fiber mixed slurry in the slurry tank is distributed on the fiber framework by a material distribution mechanism. The fiber mixed slurry is evenly attached to the three-dimensional fiber framework. After extraction, drying, and other treatments, a fiber layer is obtained. The amount of mica powder is adjusted to obtain fiber layers with different mica powder contents. The obtained fiber layers are stacked in a heat insulating body forming mold. From top to bottom, the content of mica powder in the fiber layers decreases successively. Adhesive is sprayed between adjacent two fiber layers. Then, a multi-layer structure heat insulating body is obtained by hot pressing.

[0065] S2: In the process of preparing the heat insulating body, an outer protective layer and an inner protective layer are prepared synchronously. The preparation of the outer protective layer is as follows: polyester chips 60 parts, intumescent flame retardant 3 parts, KH550 0.3 parts, and black color master batch are prepared according to the mass ratio. The PET polyester chips, intumescent flame retardant, KH550, and black color master batch are added to the extruder for melt extrusion to obtain PET particles. The PET particle material is dried and then sent to the spinning box through a melt filter and a spinning metering pump for spinning. After spinning, a black outer protective layer is obtained by web forming and hot rolling. The inner protective layer is different from the outer protective layer in that no intumescent flame retardant is added.

[0066] S3: Preparation of cover body

[0067] The inner protective layer, the heat insulating body, and the outer protective layer are sequentially stacked and placed in a composite mold for composite forming to obtain a cover body.

[0068] The inner and outer surfaces of the protective cover have hydrophobic and waterproof properties, and after encountering open fire, the outer surface is converted into a carbonaceous foam layer, thereby playing a flame-retardant and heat-insulating role, improving the protection of the protective cover, and the protective cover is simple to prepare, and through improvement of the material ratio of the heat insulating body and the outer protective layer, the existing mature preparation process and equipment are relied on to obtain a heat insulating and heat preserving heat insulating body and a flame-retardant outer protective layer, the preparation process is simple, the existing equipment does not need to be improved too much, and production investment is reduced.

[0069] The above is a preferred embodiment of the present application, which does not limit the protection scope of the present application, therefore: any equivalent changes made in structure, shape, principle, etc. according to the present application should be covered within the protection scope of the present application.

Claims

1. A method for preparing a protective cover for a new energy vehicle motor, characterized in that: Comprising the following steps: S1: forming a thermal insulation body; step a. using warp knitting equipment to weave PBI fibers to prepare a three-dimensional warp-knitted structure fiber skeleton, wherein the outer surface layer and the inner surface layer of the fiber skeleton are both two layers, and the thickness of the middle layer is not less than 1mm; Step b. prepare basalt fiber 50-70 parts, aerogel powder 15-25 parts, talcum powder 2-8 parts, sodium dodecyl benzene sulfonate 0.2-0.4 parts, KH560 0.1-0.5 parts, and mica powder 10-15 parts by mass ratio; step c. KH560 is divided into two parts, first put half of KH560, mica powder and aerogel powder into the beater, blow steam into the beater, raise the temperature to 85℃, the beater speed is 50-100r / min, beat for 5-10min, then add sodium dodecyl benzene sulfonate, crushed basalt fiber into the beater, raise the temperature to 95℃, the beater speed is 100-130r / min, beat for 10-15min, then add adhesive, talcum powder and the other half of KH560 into the beater, the beater speed is raised to 150-200r / min, beat for 5-10min; Step d. put the mixed slurry obtained in step c into the slurry tank of the wet forming equipment, place the fiber skeleton prepared in step a on the forming net of the wet forming equipment, the fiber skeleton is in a taut state on the forming net, and the mixed slurry in the slurry tank is formed in the fiber skeleton through the material distribution mechanism to obtain a fiber layer; Step e. adjust the content of mica powder in step b to obtain fiber layers with different mica powder contents according to step d; Step f. place the multiple layers of fiber layers obtained in step d in the thermal insulation body forming mold, spray adhesive between the adjacent two layers of fiber layers, from top to bottom, the content of mica powder in the fiber layer decreases in turn, and then heat press to obtain the thermal insulation body; S2: forming an outer protective layer and an inner protective layer; In the process of forming the thermal insulation body, the outer protective layer and the inner protective layer can be formed synchronously, wherein the formation of the outer protective layer is: Step g. prepare polyester chips 60-80 parts, intumescent flame retardant 3-8 parts, and KH550 0.3-0.8 parts by mass ratio; Step h. add PET polyester chips, intumescent flame retardant and KH550 into the extruder, melt extrude, prepare PET particles, dry the PET particle material, pass through a melt filter and a spinning metering pump, and then send it to the spinning box for spinning, and then perform web forming and hot rolling to obtain the outer protective layer; S3: cover body forming; Place the inner protective layer, the thermal insulation body and the outer protective layer in the composite mold in sequence and stack them to form a cover body.

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