Fan blade injection mold for exhaust fan

Abstract

The invention discloses a fan blade injection mold for an exhaust fan. The fan blade injection mold comprises a fixed mold assembly (1) and a movable mold assembly (2). A cavity (13) and a mold core (24) are both of a cylindrical split structure and comprise a plurality of structure-identical fan-shaped sub-cavities (131) and fan-shaped sub-mold cores (241) respectively, and the number of the fan-shaped sub-cavities and the fan-shaped sub-mold cores is equal to that of blades of a fan blade. The multiple sub-cavities are assembled in the circumferential direction to form an upper surface structure of the whole fan blade. The multiple sub-mold cores are assembled in the circumferential direction to form a lower surface structure of the whole fan blade. Circular-arc-shaped grooves are formed in circumferential direction of the cylindrical faces of the cavity and the mold core which are of the cylindrical split structure. The circular-arc-shaped grooves of the cavity are in sealed communication with a cooling water channel inside a fixed mold plate through the ends. The circular-arc-shaped grooves of the mold core are in sealed communication with a cooling water channel inside a movable mold plate through the ends. The cavity and the mold core of the fan blade injection mold for the exhaust fan are easy to process, and low mold manufacturing cost and mold maintaining cost can be achieved.

Description

technical field [0001] The invention relates to an injection mold, in particular to an injection mold for fan blades of a ventilation fan, and belongs to the technical field of injection molding. Background technique [0002] Ventilation fans, also known as ventilation fans and exhaust fans, are a type of air-conditioning appliance that is driven by a motor to rotate the fan blades to drive airflow to exchange indoor and outdoor air. The purpose of exhaust is to remove indoor dirty air and adjust temperature, humidity and sensory effects. [0003] The fan blade is one of the most important components of the ventilation fan. The fan blades of large industrial ventilation fans and early civil or vehicle ventilation fans are usually made of metal. In recent years, due to the extensive use of plastics, plastic injection molding such as ABS and AS with light weight and high strength Formed fan blades are widely used. [0004] The fan blade is used as the executive part of the ve...

AI Technical Summary

Problems solved by technology

[0006] 1. The structure of the cavity and core of the fan blade injection mold is relatively complex, and usually needs to be processed on a multi-degree-of-freedom controlled CNC machining center. Since the fan blade has blade curvature, the cavity and shape of the fan blade injection mold are processed. The curved surface of the core is usually milled with a milling cutter perpendicular to the processing surface, but the curved surface processing is often restricted by the blade inclination and the blade spacing. The positions of adjacent blades on the cavity and the core cause interference, resulting in overall processing difficulties and higher mold manufacturing costs;

[0007] 2. The cavity and core of the overall structure are inconvenient to maintain. The cavity or core size of a blade cannot be used after being out of tolerance due to bumping or improper use, which means that the entire cavity or core cannot continue to be used. In turn, it is difficult to ensure the overall accuracy requirements of plastic parts, and the mold maintenance costs are relatively high;

[0008] 3. The water channel of the existing fan blade injection mold is usually a traditional water channel design, that is, it is set inside the movable template and the fixed template, and is connected by multiple straight channels to form a broken line structure. Due to the cavity and core of the fan blade injection mold It is usually a circular structure, so this traditional water channel structure is not conducive to direct rapid cooling of the cavity and core, and thus cannot achieve high production efficiency;

[0009] 4. ABS, AS and other injection materials are light in weight and high in strength, so the blade wall of injection molding is usually very thin to meet the requirements of use, but the fan blade with thinner blade wall is likely to cause elastic deformation of the blade when demoulding and pushing out, and is not easy to be pushed out

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