Split Core Injection Molding Device for Tubular Parts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing injection molding technologies require cores with draft angles to facilitate easy removal and avoid additional machining processes for tubular parts with constant inner diameters.
Innovation Solution
An injection molding device using split cores with inclined split surfaces that allow sliding movement without draft angles, aided by an air supplier to enhance separation and removal of the core from the molded article.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a core with draft angle is used to facilitate core removal, then ease of operation is improved, but the molded article includes tapered surfaces requiring additional machining processes
Solution Approach 1:
The core is divided into two separate cores (first core and second core) that can move independently. Each core has a cylindrical outer shape without draft angle, but they can slide relative to each other along the axial direction, enabling easy removal while maintaining the straight cylindrical shape of the molded article.
Solution Approach 2:
The cores are designed to be movable rather than fixed. The cores can slide in the axial direction relative to each other and relative to the mold, allowing dynamic adjustment during the molding and demolding processes without requiring draft angles on the core surfaces.
2Manufacturing precision
If a straight-shaped core without draft angle is used, then manufacturing precision is improved, but ease of operation deteriorates due to material adhesion during cooling
Solution Approach 1:
The single straight core is segmented into two separate cores that can move independently. This segmentation allows the cores to be extracted from the molded article by sliding them axially, overcoming the adhesion problem without compromising the straight cylindrical shape.
Solution Approach 2:
The cores are designed with movable capability in the axial direction. By making the cores dynamic rather than static, they can be easily removed after cooling without requiring draft angles, thus maintaining manufacturing precision while improving ease of operation.
3Ease of operation
If multiple core pins are used to eliminate draft angle, then ease of operation is improved, but device complexity increases due to complicated member structures
Solution Approach 1:
The core is divided into two simple cylindrical cores without complex structures. Each core maintains a straightforward cylindrical shape with movable capability, avoiding the need for complicated member structures while enabling easy removal through axial sliding.
Solution Approach 2:
The cores are designed with simple cylindrical shapes and movable capability. By combining simplicity in shape with dynamic movement capability, the system achieves easy core removal without increasing device complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables the efficient injection molding of tubular articles with constant inner diameters using cores with simple structures and no draft angles, eliminating the need for additional machining processes.
Implementation Method 1
a slider (a slider 3, which will be described later, for example) that causes the first core or the second core to move in a sliding manner and be inserted into and pulled out of the cavity
Implementation Method 2
an air supplier (an air supplier 6, which will be described later, for example) that supplies air to the split surfaces
Data Source
AI summary
To provide an injection molding device capable of injection-molding a molded article in a tubular shape with a constant inner diameter by using a core with a simple structure with no draft angle. An injection molding device that injection-molds a molded article in a tubular shape with a constant inner diameter includes: a first mold and a second mold that form a cavity in a clamped state; a first core and a second core that are formed by splitting a core in a columnar shape disposed inside the cavity and have split surfaces inclined with respect to an axial center direction of the core and split from one end to the other end of the cavity in the axial center direction; and a slider that causes the first core or the second core to move in a sliding manner and be inserted into and pulled out of the cavity, in which the slider causes the first core or the second core to slide in a direction in which an angle formed with the axial center direction is within a range of greater than 0 degrees and less than an inclination angle of the split surface in a sectional view including the axial center and perpendicularly intersecting the split surface.