Structural improvement and injection mould design for plastic speaker
The structural analysis of the plastic parts is shown under the hood of a wireless speaker. Speakers as network popular product, has the following special structure requirement: comfortable, sound box under the cover part, shell, shell materials TPE for soft plastic, inner material for PC + ABS hard plastic.
Appearance fashion, the plastic shell surface with the Roman character for hollow out "I, I, R/marked volume, in order to reduce subsequent printing work, and it will never wear. Plastics diversified colors, strong visual impact.
The appearance of the plastic parts is not allowed to have obvious gate marks and surface flow marks.
The plastic parts are sealed around the edges of the plastic parts, which should be fitted with soft plastic and overfilled, and the effect of the sound cavity is sealed by soft plastic.
Plastic parts molding process analysis and structural improvement: 2010-1220), male, fujian xiamen, assistant engineer, mainly engaged in plastic mould design. Mechanical structure design work, address xiamen xiahe four room 201 of the 1120 guangzhou hongtai group (xiamen) co., LTD. Plastic mold factory (phone) according to the request of plastic parts design and mould, injection production needs, the original plastic parts structure design changes are as follows: the original TPE plastic interval between shell around sign a narrow, easy to form the weld mark, here affect the appearance. After improvement, the PC + ABS plastic inner mark symbol local area reduction, in order to increase the TPE shells in the local volume, as shown in (b) dark under the concave area, avoid TPE shells welding scar in the middle of the plastic button.
The position of the TPE case when the design of the original plastic parts is inconsiderate, even if the gate position indicated by (a) is applied, the water gate marks will be formed on the surface of the plastic parts. After consideration, change the position of the TPE shell gate as shown in (b). After molding, the surface of the gate is covered with trademark paper, which does not affect the appearance.
Filling process of 73 mm filling quality of 86 g. when mould temperature of 85 ° C, quickly in high injection pressure and injection speed of mold filling, easy to cause the TPE material material overflow in parting surface. After changes about the structure of plastic parts, in the PC + ABS inner attaches the whole circle of heightening 1 mm relative to TPE shell forming natural circle of PC + ABS sealants, prevent when TPE shell molding flash flash, such as shown below.
(a) 3 d map zoom in x area to the Z amplified speakers under cover (b) 2 d figure (a) (b) the modified design original design local structure change 3 PC + ABS inner shell mould structure design (1) according to the existing 2 680 kn two-color injection molding machine single vice mould according to the structural characteristics of the modified plastic parts, injection mould design modulus maximum width of 350 mm again considering the plastic parts to four direction take consider the following items: core, determine the mold with mold 1 cavity point gate double-color plastic injection molding mold structure.
(2) the inlet of the PC + ABS material is designed for the TPE material coverage area (see (a)), the TPE feed inlet position is shown in (b). The first restorer of the die is installed on the set. When clamping injection, injection first PC + ABS material, the fixed die force, fixed template press reset lever a certain height, first reset institutions on core rises, such as is shown above, in the PC + ABS on the inner shell forming the four TPE material feeding holes. After rotating the mold, the resetting bar is not determined by the injection of TPE, and the core of the reset is reduced, and the TPE feed channel is given out.
(a) (a) the original burning mouth position PC + ABS material flow and inlet (b) TPE material flow and inlet inlet location Settings reset institutions first sketch the improved burning mouth position TPE shell gate location to improve PC + ABS the local structure improvement (3) the TPE inner shell cavity as shown in the cooling system. The cooling channel adopts a circular distribution and is as close to the surface as possible. Water well cooling structure is adopted in the core area to ensure cooling effect.
The structure of the TPE housing cooling system is very deep in the plastic part cavity, and the TPE material is very easy to adhere to the cavity.
Design to consider in the second cavity within the design of the injection of TPE push block, block is equipped with spring, at the bottom of the moving mold apart, blocks under the action of a spring, promote plastic parts in the dynamic model, until the move is completely separated from the mold. The auxiliary ejection mechanism is shown.
The structure of the die first cavity (injection PC + ABS) is shown. The structure of the second cavity (injection TPE) is shown in 0.
4 mold working process according to the mould dimension and enterprise existing injection molding machine, choose the M - 268 dm injection molding machine, slewing mechanism for rotating disc, driven by servo motor, the moving mould part to rotate 180 °. The first cavity (see) the injection PC + ABS material, the second cavity (see 0) injection TPE.
First cavity injection mold working process is: the injection molding machine to the PC + ABS material, molten material after pressure maintaining and cooling the mould for the first time, remove the PC + ABS pouring system setting material, products on the dynamic model with dynamic model rotate 180 ° die, at this time to reset institutions work, open the TPE material feed port. The first cavity injection of PC + ABS material (the second batch of plastic parts), at the same time the second cavity injection of TPE material, molten material after pressure maintaining and cooling, the second open mold, the first cavity to take out the PC + ABS material pouring system setting. Dynamic model rotated 180 ° injection plunger push push driven push rod and push boards to launch the second cavity of TPE material gating system and double color molding plastic parts.
With the improvement of the structure of the plastic parts and the reasonable design of the mould structure, the plastic parts are of good quality and the ratio of plastic parts is above 92%.
Double-color plastic injection mould design, in accordance with the requirements of plastic parts, considering double-color plastic injection mould production process and production of plastic injection molding defects are predicted and the structure improvement, in order to shorten the mold development cycle, make the product into the market as early as possible.