Design of injection mould for complex plastic parts of automobile air conditioning pipe joint
A two plate mould was designed for the injection molding of a complex plastic part of an automobile air condition-ing pipe joint,which solved the practical problem of difficult demoulding and automated injection molding production due to the complex structure of the plastic part.In this plastic part,four irregular structural features were added to the cylindrical shell body,including a 90° bent pipe joint,an angle straight pipe joint,a flange platform straight pipe joint,and a straight pipe+65° bent pipe joint,making the demoulding mechanism design of the plastic part very difficult.To solve this problem,design methods such as inte-grated classification of demoulding directions were adopted in the design to design the demoulding mechanism of plastic parts according to regions.Six fixed mould sliding blocks were designed on the fixed mould side with features of 90° bend pipe joint and angle straight pipe joint for the first core pulling demoulding of these two features.The core pulling action of the six mechanisms was mechanically driven by the opening of the mold on the side of the fixed mould to complete the fixed mould first pulling action.Four demoulding mechanisms were installed on the moving side of the mould including two slider mechanisms,a slider+bend tube composite mechanism,and a large-sized pipe pushing mechanism.Two slider mechanisms were driven by angle guide columns and oil cylinders respectively for demoulding the flange platform through pipe joint.The slider+bend tube composite mechanism was used for demoulding the joint features of straight tube+65° bend tube.In this mechanism,the angle guide column drived the slider to complete linear core pulling,and then the oil cylinder drived the bend tube core to drive the linear core pulling slider to move togeth-er,completing the rotational core pulling demoulding of the 65°bend tube features.The plastic part was finally pushed out by a large-sized pipe pushing mechanism to achieve complete demoulding.
automotive air conditioning pipe jointfirst core pulling on fixed mouldinjection moldingbend core pullingcomposite mechanismpush tubemould design