A motor soundproof cover and its manufacturing method

Abstract

This invention relates to a motor soundproof cover and its manufacturing method. The motor soundproof cover includes a housing (1) and a plurality of assembly components (2) disposed on the housing (1). The housing (1) includes a surface non-woven fabric layer (11), a glass fiber layer (12), and a bottom non-woven fabric layer (13) arranged sequentially, with a PU layer (3) connected to the bottom non-woven fabric layer (13). Compared with the prior art, this invention has advantages such as stronger high temperature resistance, better motor enclosure, and stronger sound absorption and insulation performance.

Description

Technical Field

[0001] This invention relates to the field of soundproof cover technology, specifically to a motor soundproof cover and its manufacturing method. Background Technology

[0002] Motor sound insulation covers are products located inside the engine compartment of new energy vehicles. They are typically used to wrap around the motor. When the motor starts, it emits a whistling sound, generating noise. Therefore, there is an urgent need for a product that can effectively insulate and absorb sound. Existing technology mainly involves placing sound-absorbing cotton on the top cover inside the engine compartment, but its sound insulation effect is very limited, restricting its applicability and practicality. Furthermore, the motor generates heat during operation, thus requiring the sound insulation materials used to have certain high-temperature resistance.

[0003] Invention patent CN110920179A discloses a sound insulation cover part for an electric vehicle battery and its manufacturing method. The part includes, from top to bottom, a non-woven fabric layer, a flame-retardant EPDM layer, and a PU layer, as well as metal clips mounted on the PU layer. The flame-retardant EPDM layer and PU layer are placed in an oven and heated to soften the EPDM surface. A blank is then placed into a mold using a feeding device. The non-woven fabric, the heated EPDM, and the PU are arranged sequentially from top to bottom in the mold, followed by hot pressing. The mold is then cooled and shaped at room temperature, excess material is removed, and metal clips are attached to the resulting part to produce the sound insulation cover part for the electric vehicle battery. This invention has excellent sealing, heat resistance, flame retardancy, and heat insulation properties. However, the manufacturing process of this sound insulation cover part is relatively complex, its high-temperature resistance is limited, and it cannot be precisely bent and assembled. It also has weak encapsulation of the motor and poor sound absorption and insulation. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects of the prior art by providing a motor soundproof cover and its manufacturing method, which has stronger high temperature resistance, better motor enclosure, and stronger sound absorption and insulation performance.

[0005] The objective of this invention can be achieved through the following technical solution: a motor sound insulation cover, comprising a housing and multiple assembly components disposed on the housing; the housing comprises a surface non-woven fabric layer, a fiberglass layer, and a bottom non-woven fabric layer arranged sequentially, with a PU layer connected to the bottom non-woven fabric layer. The fiberglass layer possesses excellent properties such as high temperature resistance, oil resistance, corrosion resistance, and sound insulation, and can serve as a carrier for PU foaming, and can be bent and assembled. In this invention, sound waves, after passing through the PU layer and the non-woven fabric, are repeatedly refracted in the fiberglass layer, greatly reducing the sound wave energy, thus achieving excellent sound absorption performance.

[0006] Furthermore, the glass fiber layer is a phenolic resin type glass fiber layer with a unit area weight of 700-900 g / m². 2 .

[0007] Furthermore, the phenolic resin-type glass fiber has a diameter of 5.5–7 μm, a length of 0.3–0.8 mm, and a thermal conductivity of 0.033–0.04 W / mK.

[0008] The PU layer has a unit volume density of 110-130 kg / m³. 3 The thickness is 8-30 mm, preferably 10-30 mm, and it is made by foaming isocyanate and polyether in a weight ratio of 40-45:100, with a porosity of 0.81-0.9.

[0009] The PU layer has a large number of pores, and the pores are dense, which has a good blocking effect on sound waves, thereby increasing the sound absorption, while also having a certain strength.

[0010] The surface nonwoven fabric layer has a unit area weight of 110-130 g / m². 2 The fabric has a fine surface, a soft feel, and a needle-punched nap. This style of fabric is often used in mid-range vehicles and has properties such as flame retardancy and chemical resistance. The non-woven fabric layer on the bottom has a unit area weight of 140-160 g / m². 2 This is used to prevent the foaming material from penetrating into the glass fiber layer during foaming.

[0011] The assembly components include a ferrule-shaped retaining ring washer, a fixing washer, and rivets that mate and connect with each other, and are located at the indentation edge of the housing. The ferrule-shaped retaining ring washer comprises a main body, screw holes at both ends of the main body, and a ferrule-shaped retaining ring located in the middle of the main body. The main body thickness is 0.6–1.0 mm, preferably 0.8 mm; the screw hole diameter is 6–8 mm, preferably 7.1 mm; and the vertical distance between the highest point of the ferrule-shaped retaining ring and the main body is 1.5–2.5 mm, preferably 2.1 mm. The ferrule-shaped retaining ring is composed of annularly arranged inclined spring pieces, one end of which is connected to the main body, and the other end is a free end. The ferrule-shaped retaining ring washer is made of 308 stainless steel and is fixed to the part body by riveting. It has rust-proof properties, and its shape and dimensions are designed according to the motor stud, making installation and disassembly convenient. The shape of the ferrule-shaped retaining ring facilitates its installation on the motor cylinder; it can be directly pushed in and is not easily removed.

[0012] A method for manufacturing the above-mentioned motor sound insulation cover includes the following steps:

[0013] Step 1: Place the blank with the surface non-woven fabric layer, glass fiber layer and bottom non-woven fabric layer in the mold cavity and heat press to shape it;

[0014] Step 2: Open the mold and place the product from Step 1 into the cooling fixture for cooling;

[0015] Step 3: Remove the cooled product, remove the edge material, and obtain the shell;

[0016] Step 4: Place the shell obtained in step 3 into the foaming mold and inject foaming material to foam;

[0017] Step 5: Open the mold, remove excess foam material, and obtain a shell with a PU layer;

[0018] Step 6: Install multiple assembly components on the housing to obtain the motor sound insulation cover.

[0019] Furthermore, the hot pressing and shaping temperature in the first step is 210–250℃, the press pressure is 17–23 MPa, and the mold closing and pressure holding time is 110–130 seconds. The hot pressing and shaping process leaves indentations on the shell, which can be bent along the indentations for easy subsequent assembly. The cooling fixture temperature in the second step is 5–35℃, and the cooling time is 2–3 minutes. The cooling fixture includes positioning fixtures and heat dissipation equipment.

[0020] The foaming material described in step four is obtained by uniformly mixing isocyanate and polyether at a weight ratio of 40-45:100, with a foaming temperature of 60-65℃, a pressure of 150-160 bar, and a curing time of 105-115s. The PU layer bonded in this way has a stronger adhesion to the non-woven fabric on the bottom surface than that bonded by molding or gluing.

[0021] The assembly components described in step six are set up as follows: place a swivel spring washer on the upper surface of the housing and a fixing washer on the lower surface. Pre-bend the housing according to the indentation produced by hot pressing. Then, pass the rivet through the swivel spring washer, the housing, and the fixing washer to rivet and fix them.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] 1. By incorporating a glass fiber layer, this invention offers enhanced high-temperature resistance, flexibility, sound insulation, good motor enclosure, and superior sound absorption and insulation performance.

[0024] 2. This invention can absorb sound through the numerous pores in the PU layer, resulting in good sound absorption and insulation effects;

[0025] 3. This invention uses glass fiber as the base material, and its main component is silicon dioxide. It is non-flammable, chemically stable, and has excellent flame retardant properties. The first combustion time of a single sample is less than 10 seconds, and there are no molten droplets.

[0026] 4. This invention can meet various high and low temperature environments, such as: no deformation, no structural or functional damage, etc. in a temperature cycling test of -40℃ to 120℃ for 30 cycles (15 days);

[0027] 5. This invention uses stainless steel plum blossom spring washers to install and fix the motor sound insulation cover, which has rust-proof properties, and the shape and size are designed according to the motor studs, making installation and disassembly convenient. Attached Figure Description

[0028] Figure 1 This is a partial structural diagram of the motor sound insulation cover of the present invention;

[0029] Figure 2 This is a schematic diagram of the assembly components of the present invention;

[0030] Figure 3 This is an assembly diagram of the present invention;

[0031] Figure 4 This is a front view of the motor sound insulation cover assembly of the present invention;

[0032] Figure 5 This is a top view of the motor sound insulation cover assembly of the present invention;

[0033] In the diagram: 1-shell, 11-surface non-woven fabric layer, 12-fiberglass layer, 13-bottom non-woven fabric layer, 2-assembly assembly, 21-clover spring washer, 211-main body, 212-screw hole, 213-clover spring, 22-fixing washer, 23-rivet, 3-PU layer, 4-motor sound insulation cover assembly. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. The following embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.

[0035] Example 1

[0036] A type of motor sound insulation cover, such as Figure 1 As shown, the device includes a housing 1 and multiple assembly components 2 mounted on the housing 1. The housing 1 includes a surface nonwoven fabric layer 11, a glass fiber layer 12, and a bottom nonwoven fabric layer 13 arranged sequentially from the outside to the inside. The bottom nonwoven fabric layer 13 is also connected to a 10mm thick PU layer 3. The surface nonwoven fabric layer 11 has a unit area weight of 110-130g / m². 2 The fiberglass layer 12 has a unit area weight of 700-900 g / m². 2 The bottom non-woven fabric layer has a unit area weight of 140-160 g / m². 2 .

[0037] The shell 1 is made by the following method:

[0038] Step 1: Place the blank with the surface non-woven fabric layer 11, glass fiber layer 12 and bottom non-woven fabric layer 13 in the mold cavity for hot pressing and shaping. The hot pressing and shaping temperature is 210-250℃, the press pressure is 17-23MPa, and the mold closing and pressure holding time is 110-130s.

[0039] Step 2: Open the mold and place the product from Step 1 into a cooling fixture at 5-35℃ for 2-3 minutes to cool.

[0040] Step 3: Remove the cooled product, remove the edge material, and obtain shell 1.

[0041] Indentations are formed on the surface of the housing 1 during the hot pressing process, and the housing 1 can be bent and assembled along the indentations.

[0042] PU layer 3 is attached to the bottom nonwoven fabric layer 13 using the following method:

[0043] Step 1: Place shell 1 into a foaming mold, inject a mixture of isocyanate and polyether in a weight ratio of 40-45:100 for foaming, foaming temperature is 60-65℃, pressure is 150-160 bar, curing time is 105-115s;

[0044] Step 2: Open the mold and remove any excess foam material.

[0045] The housing 1 with the PU layer 3 is assembled onto the motor of a General Motors vehicle via multiple assembly components 2, such as... Figures 2-3 As shown, assembly component 2 includes a swivel spring washer 21, a fixing washer 22, and a rivet 23. During assembly, assembly component 2 is placed next to the indentation of housing 1. The swivel spring washer 21 is placed on the upper surface of housing 1, and the fixing washer 22 is placed on the lower surface. After the housing 1 is pre-bent along the indentation to wrap the motor, the rivet 23 passes through the swivel spring washer 21, housing 1, and fixing washer 22, and is connected to the motor stud to rivet and fix housing 1, so that housing 1 is installed on the motor, and the PU layer 3 connected to the bottom non-woven fabric layer 13 is tightly attached to the motor.

[0046] The specific structure of the plum blossom retaining ring washer 21 is as follows: Figure 3 As shown, it includes a main body 211, screw holes 212 at both ends of the main body 211, and a plum blossom retaining ring 213 in the middle of the main body 211. The thickness of the main body 211 is 0.8mm, the diameter of the screw holes 212 is 7.1mm, and the vertical distance between the highest point of the plum blossom retaining ring 213 and the main body 211 is 2.1mm.

[0047] The assembled motor soundproof cover assembly has the following structure: Figures 4-5 As shown.

[0048] Example 2

[0049] A motor soundproof cover, wherein the thickness of the PU layer 3 is 20mm, and the rest is the same as in Example 1, wherein the motor soundproof cover is assembled onto the motor of a General Motors vehicle.

[0050] Example 3

[0051] A motor sound insulation cover, wherein the thickness of the PU layer 3 is 30mm, and the rest is the same as in Example 1, wherein the motor sound insulation cover is assembled onto the motor of a General Motors vehicle.

[0052] Comparative Example 1

[0053] The soundproof cover, manufactured according to the method of invention patent CN110920179A, is then assembled onto the motor of a General Motors vehicle.

[0054] The performance of the soundproof enclosures of Examples 1-3 and Comparative Example 1 was tested, and the obtained parameters are shown in the table below:

[0055] project Example 1 Example 2 Example 3 Comparative Example 1 Average sound absorption 0.6 0.63 0.67 0.52 Installation time 30s 30s 30s 48s Maximum temperature resistance 180℃ / 200h 180℃ / 200h 180℃ / 200h 180℃ / 150h Flame retardant V0 V0 V0 V0

[0056] As can be seen, compared with the existing technology, the soundproof cover of the present invention has stronger sound absorption performance, is easier to install, and is more resistant to high temperatures.

[0057] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A motor sound insulation cover, characterized in that, It includes a housing (1) and a plurality of assembly components (2) disposed on the housing (1); the housing (1) includes a surface non-woven fabric layer (11), a glass fiber layer (12) and a bottom non-woven fabric layer (13) disposed in sequence, and the bottom non-woven fabric layer (13) is connected to a PU layer (3). The glass fiber layer (12) is a phenolic resin type glass fiber layer with a unit area weight of 700~900g / m². 2 ; The PU layer (3) is foamed from isocyanate and polyether in a weight ratio of 40~45:100, and has a porosity of 0.81~0.

9. The assembly component (2) includes a plum blossom snap ring washer (21), a fixing washer (22), and a rivet (23) that are connected to each other and are set at the indentation edge of the housing (1); the plum blossom snap ring washer (21) includes a main body (211), screw holes (212) set at both ends of the main body (211), and a plum blossom snap ring (213) set in the middle of the main body (211). The thickness of the main body (211) is 0.6~1.0mm, the diameter of the screw hole (212) is 6~8mm, and the vertical distance between the highest point of the plum blossom snap ring (213) and the main body (211) is 1.5~2.5mm. The plum blossom snap ring (213) is composed of an inclined spring piece arranged in a ring. One end of the inclined spring piece is connected to the main body, and the other end is a free end. The plum blossom snap ring washer (21) is fixed to the body of the part by riveting, and the surface dimensions are designed according to the motor stud. The method for manufacturing the motor sound insulation cover includes the following steps: Step 1: Place the blank with the surface nonwoven fabric layer (11), glass fiber layer (12), and bottom nonwoven fabric layer (13) in the mold cavity and heat press to shape it; Step 2: Open the mold and place the product from Step 1 into the cooling fixture for cooling; Step 3: Take out the cooled product, remove the edge material, and obtain the shell (1); Step 4: Place the shell (1) obtained in step 3 into the foaming mold and inject foaming material to foam; Step 5: Open the mold, remove the excess foam material, and obtain the shell (1) with PU layer (3); Step 6: Set multiple assembly components (2) on the housing (1) to obtain the motor sound insulation cover; The hot pressing and shaping temperature in the first step is 210~250℃, the press pressure is 17~23MPa, the mold closing and pressure holding time is 110~130s, and the hot pressing and shaping process leaves indentations on the shell, which can be bent along the indentations; The housing (1) with PU layer (3) is assembled onto the motor of General Motors by multiple assembly components (2). During assembly, the assembly components (2) are set next to the indentation of the housing (1), a swivel spring washer (21) is placed on the upper surface of the housing (1), and a fixing washer (22) is placed on the lower surface. After the housing (1) is pre-bent along the indentation to wrap the motor, the rivet (23) passes through the swivel spring washer (21), the housing (1) and the fixing washer (22), and is connected to the motor stud to rivet and fix the housing (1), so that the housing (1) is installed on the motor, and the PU layer (3) connected to the bottom non-woven fabric layer (13) is tightly attached to the motor.

2. The motor sound insulation cover according to claim 1, characterized in that, The diameter of phenolic resin-based glass fiber is 5.5~7μm, the length is 0.3~0.8mm, and the thermal conductivity is 0.033~0.04w / mk.

3. The motor sound insulation cover according to claim 1, characterized in that, The PU layer (3) has a unit volume density of 110~130 kg / m³. 3 The thickness is 8~30mm.

4. The motor sound insulation cover according to claim 1, characterized in that, The surface nonwoven fabric layer (11) has a unit area weight of 110~130g / m². 2 The unit area weight of the bottom nonwoven fabric layer (13) is 140~160g / m². 2 .

5. The motor sound insulation cover according to claim 1, characterized in that, The temperature of the cooling fixture mentioned in the second step is 5~35℃, and the cooling time is 2~3 minutes.

6. The motor sound insulation cover according to claim 1, characterized in that, The foaming material described in step four is obtained by uniformly mixing isocyanate and polyether in a weight ratio of 40~45:100, with a foaming temperature of 60~65℃, a pressure of 150~160 bar, and a curing time of 105~115s. The assembly component (2) described in step six is ​​set up as follows: place a plum blossom snap ring washer (21) on the upper surface of the housing (1) and a fixing washer (22) on the lower surface. Pre-bend the housing (1) according to the indentation generated by hot pressing. Rivet (23) is passed through the plum blossom snap ring washer (21), the housing (1) and the fixing washer (22) for riveting and fixing.

Images