Ejector Pin Research Articles

Design and Analysis of Plastic Injection Mould for CAM BUSH with Submarine Gate

This Paper focused on Design and Analysis of an automatic plastic injection mould for production of CAM BUSH. Cam Bush is used as a indexing device in ON/OFF Load Tap changer device of high voltage transformer and serves as the connector between the indexing head and the power changing gears. An injection mould is a tool which is used for production of plastic components in large numbers in a short span of time. Modeling in done by using Unigraphics (NX 7.5) and Auto Desk Mould flow Plastic Insight is use for Mould flow Analysis for CAM BUSH filling rate, cooling system location and Location of submarine gate. The moulding tool consists of the Top plate, Cavity plate, Core plate, Spacer blocks, Ejector plate and the Bottom plate. In this six core pins and six ejector pins are provided on injection mould because the required cam bush has six indexing holes. The material use is Oil Hardened Non-shrinking Steel (OHNS) for the core and cavity, and EN353 for the Tie Rod, guide bushes, core pins, ejector pins, locator ring and the sprue bush and Mild Steel for other plates are selected. The elements of injection moulding tool has designed and analyzed. Submarine gate and Baffle circular hole cooling system has provided in the moulding tool to increase the productivity and good surface finish. The required Nylon-66 Cam bush component will produced with this moulding tool with the various parameters of injection moulding machine.

Analysis of Crack Formation in Germanium Substrate at AlInGaP Die Bonding Process

Cracked die is a serious failure mode in Light Emitting Diode (LED) industry – affecting the LED quality and long-term reliability performance. In this paper, an investigation has been carried out to find out a relation between die bonding force and the occurrence of die crack at Germanium (Ge) substrate due to die attach (DA) ejector pin indentation. Based on the analysis, the results show that cracks start to occur at 60 gram-force (gF) bond force and above. The crack length at the die substrate increases with respect to the bond force. These indented dies were further analyzed by using Scanning Electron Microscope (SEM). The results show plastic deformation, slip traces and material pile-up at the vicinity of ejector pin crater. Some samples were sectioned using Focus Ion Beam (FIB) and it was found the crack depth does not exceed beyond 20.5μm and it follows the (111) plane. These findings, concludes that cracks start to appear at 60gF and they are confined to surface level even indented at extreme load (140gF). These cracks are far away from the active region of LED.

DESIGN OF ‘PLASTIC INJECTION MOLD’ FOR AN ‘AIR VENT BEZEL’ THROUGH FLOW ANALYSIS (CAE) FOR DESIGN ENHANCEMENT

Designer's of plastic injection Molds need to study from this point of view, the type of Mold to be designed, the physical Mold orientation, the dimensions for each of the element in the Mold, the location of the gate, runner, requirement of insert, draft angle requirement, shrinkage factor, location of cooling channels. Design can also be simplified by using standardized parts of the mold such as ejector pins. By eliminating the obstruction to smooth flow of plastic a good of quality component can be achieved. The effort of this thesis work is to find out the nuances in the Plastic Injection Mold Design while borrowing the inputs from the Flow Analysis (CAE) conducted for the 'Air vent bezel' to study the behavior of the Melt during flow. The Mold Design would

The Injection Mold Design of Clamshell Phone Upper Cover

The design of injection die on the upper cover of clamshell phone is introduced. The dual-plate die has side gate for opposite glue injection, the parts are ejected by ejector pin, the side reversed buckle contains three blocks, the reversed buckle at flip shaft consists of two inner sliders, and all the eight inner reversed buckles are made up of inclined pushing rods, and the cooling system embraces "U" shaped cooling waterway. Its application in practice has proved the reasonable die structure, smooth remolding, and qualified plastic part design.

Modelling and Analysis of Extrusion Die and Bolt Ejector Pin

The computer aided tools and recent developments of engineering, emphasizes the importance of bringing manufacturing process into early stage for product and process design. The implied significance is that it becomes vital to reduce cost of product by extensive use of CAD tools for product formation without actually building the product. In this paper, CAD tools are used to design an extrusion die for bolt ejector pin. In this paper, the extrusion die used to produce the pin is modeled using Pro-E, a CAD tool. Then, the die is analyzed for the maximum extrusion load condition using ANSYS software, a Finite Element Analysis simulation (FEA) tool. The simulation results are compared with yield stress of material. After the die has been designed, the pin was extruded using the die. In order to evaluate the strength of extruded pin, the pin was also modeled and analyzed using ANSYS tool where it was found to be safe for its maximum ejection load condition.Keywords:Extrusiondiedesign,ejectorpin,Computeraidedmodelling(CAD),FiniteElementAnalysis(FEA).

MOLTEN METAL FLOW ANALYSIS OF HOUSING COMPONENT

Die casting is a versatile manufacturing technique in which molten metal is poured into die. The die consists of core and cavity, an impression is formed when these core and cavity are closed together. This impression forms the shape and size of the component. The main challenge in die casting is design and manufacturing of die. Integration of design and analysis yields to better results. Die casting is often encountered with many problems, few of such problems are blowholes, improper filling, scratch marks, weld lines, cracks, cold shut, porosity, blisters, ejector pin marks, etc. usually these defects are caused due to improper design of dies, or due to incorrect parameters such as injection pressure, cycle time, cooling circuits and other such parameters. In order to eliminate such defects a set of analysis has to be carried to ensure that design and other parameters are safe and efficient. Through analysis is carried to understand how the molten metal behaves inside the dies once it is injected, a clear picture about how the molten metal gets solidified is obtained during analysis. Any defects if present can be studied by analyzing the results of analysis. In this paper pro cast analysis software is used for analysis purpose, the flow of molten metal inside the impression was studied and changes to be made to the design were analyzed. Behavior of molten metal at different stages of time such as temperature variations, pressure variations is studied. Different graphs are plotted to study the behavior inside the dies.

Slide design and manufacturing issues in prototype tooling

When a prototype tool for injection molding has to deal with undercut features, the difficulty involved in manufacturing the tooling increases considerably as slides must be used. However, the use of slides in prototype tooling has not been extensively explored. Various design and manufacturing issues, mainly related to the geometry, accuracy and extraction of slides, may prevent these working satisfactorily in a multi-piece mold. In this work, the main types of undercuts are analyzed and some issues related to the design and manufacture of slides for prototype tooling are discussed. A study is carried out to understand a specific issue related to peripheral milling accuracy, and a fit procedure is proposed to overcome this. Polymeric inserts for a test part were manufactured following the proposed design and manufacturing recommendations and fit procedure. The mold was used to produce polypropylene prototypes in an industrial injection molding machine. The results showed that similar design and manufacturing concepts can be applied to different types of undercuts. Extraction of the slide worked satisfactorily, and ejector pins were not required. Finally, the proposed solution to ensure computer numerical control machining produced an adequate slide fit proved successful and significantly reduced post-processing time.

CAST METAL FLOW ANALYSIS OF INTERMEDIATE FLANGE

The production of aluminium alloy die castings has been seeing a continuous increase to answer the strong demand by the automotive industry for higher strength and lighter weight. The die castings for automotives are required of not only high quality as of course but also thin walls and a high dimensional precision, thus it is essential to provide advanced casting technologies for the manufacturing of these castings. The main challenge in die casting is design and manufacturing of die. Integration of design and analysis yields to better results. Die casting is often encountered with many problems, few of such problems are blowholes, improper filling, scratch marks, weld lines, cracks, cold shut, porosity, blisters, ejector pin marks, etc. usually these defects are caused due to improper design of dies, or due to incorrect parameters such as injection pressure, cycle time, cooling circuits and other such parameters n order to eliminate such defects a set of analysis has to be carried to ensure that design and other parameters are safe and efficient. Through analysis is carried to understand how the molten metal behaves inside the dies once it is injected, a clear picture about how the molten metal gets solidified is obtained during analysis. Any defects if present can be studied by analysing the results of analysis. In this paper Adestefan analysis software is used for analysis purpose, the flow of molten metal inside the impression was studied and changes to be made to the design were analysed. Behaviour of molten metal at different stages of time such as temperature variations, pressure variations is analysed.

Injection Mould Design of Mobile Phone Back Shell

This article introduces the injection mould design of mobile phone back shell. The mould adopts 3-plate mold structure, pin-point gate for feeding in the glue, ejector pin and pieces for stripping. The under-cut at the side edge adopts 3-side sliding block molding, and the cooling system adopts “U”-shape coolant gallery. It is proved by production practice that the mould structure is reasonable, stripping smoothly and the plastic parts quality meets the design requirements.

Design and Fabrication of an Injection Moulding Tool for Cam Bush with Baffle Cooling Channel and Submarine Gate

This research works is focused on design and fabrication of an automatic injection moulding tool for production of CAM BUSH which is used in electrical engines as a connector. An injection mould is a tool which is used for production of plastic components in large numbers in a short span of time. The moulding tool consists of the Top plate, Cavity plate, Core plate, Spacer blocks, Ejector plate and the Bottom plate. In this work, six core pins and six ejector pins are provided on injection mould because the required cam bush has six indexing holes. The material, Oil Hardened Non-shrinking Steel(OHNS) for the core and cavity, EN353 for the guide pillar, guide bushes, core pins, ejector pins, locator ring and the sprue bush and Mild Steel for other plates are selected. The elements of injection moulding tool have been designed, fabricated and assembled. Submarine gate and Baffle circular hole cooling system has been provided in the moulding tool to increase the productivity and good surface finish. The required Nylon-66 Cam bush component is produced with this moulding tool by properly controlling the various parameters of injection moulding machine.

LED칩 제조용 다이 본더의 전산 설계 및 해석에 대한 연구

LED 칩 패키징에서 다이 본딩은 분할된 칩을 리드 프레임에 고정시켜 칩이 이후 공정을 견딜 수 있도록 충분한 강도를 제공하는 중요한 공정이다. 기존의 다이 본더의 픽업 장치는 단순히 콜렛의 하강 동작과 이젝터 핀의 상승 동작만으로 구동되어 픽업 장치와 다이가 접촉하는 순간 충격에 의한 다이의 손상과 위치 정렬 오차에 대한 문제점이 발생한다. 본 연구에서는 위치 정렬 에러 및 다이의 손상을 최소화시키기 위하여 고정밀, 고속 이송이 가능한 픽업 헤드를 사용한 다이 본더 시스템을 개발하였다. 구조적 안정성을 평가하기 위해 다이 본더의 유한요소모델을 생성하였고 구조 해석을 수행하였다. 그다음, 다이 본더의 작동 주파수에 대해 픽업 헤드의 유한요소모델을 이용하여 진동해석을 수행하였다. 해석 결과, 다이 본더에 작용하는 응력 및 변위, 고유진동수에 대해 분석하였고 개발된 시스템의 구조적 안정성에 대해 확인하였다. In LED chip packaging, die bonding is a very important process which fixes the LED chip on the lead frame to provide enough strength for the next process. Conventional pick-up device of the die bonder is simply operated by up and down motion of a collet and an ejector pin. However, this method may cause undesired problems such as position misalignment and/or severe die damage when the pick-up device reaches the die. In this study, to minimize the position alignment error and die damage, a die bonder is developed by adopting a new pick-up head for precise alignment and high speed feeding. To evaluate structural stability of the designed system, required finite element model of the die bonder is generated, and structural analysis is performed. Vibration analysis of the pick-up head is also performed using developed finite element model at operation frequency range. As a result of the analysis, deformation, stress, and natural frequency of the die bonder are investigated.

Enhancement of weld line mechanical strength using a novel ejector‐pins compression system

AbstractThis study proposes a novel ejector‐pins compression system (EPCS) to improve the mechanical strength of weld lines that are formed in the injection molding process. Weld lines are significant defects that affect injection molding quality, causing the poor appearance and low mechanical strength of injection‐molded parts. In this experiment, several ejector pins are placed intentionally near the weld lines appearing, and are initially sunken beneath the cavity surface to form a reflow trap such that some of the molten plastics are allowed to flow into it during the filling process. These molten plastics are then compressed by the arisen ejector pins. Accordingly, the compressed molten plastics reflow through the weld lines, disordering the molecular orientation. Experimental verification revealed that the use of an EPCS can efficiently eliminate the orientation of the molecules parallel to the weld line. The specimens' impact strength of using EPCS can increase to between one and two times than that of conventionally injection‐molded. Therefore, this simple and novel method is feasible for greatly improving the mechanical strength of weld lines. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013

Using VBA Technology to Develop Two-Dimensional Gallery System of Components of Injection Moulds for Plastics

The development process and method of using VBA technology to develop two-dimensional gallery system of components of injection moulds for plastics taking ejector pin for example is described in detail, which includes establishing parameters database of components, design and calling of user interface, program and menu. The two-dimensional gallery system of components of injection moulds for plastics developed in AutoCAD can generate two-dimensional drawing automatically with the design parameters that user selects and it is convenient for user to plot.

Knowledge-based part similarity measurement utilizing ontology and multi-criteria decision making technique

When existing parts are re-used for the development of a new product or business-to-business transactions, a method for searching parts from a database that best meet user’s requirements is essential. The core of a part search method is to measure the similarity between parts’ specifications and the user’s input data in an efficient manner. In this paper, the authors suggest a new method for part similarity measurement using ontology and multi-criteria decision making (MCDM) technique and discuss its technical details. This method ensures interoperability with existing engineering information management systems, represents part specifications in a formal manner, and has generality in search procedure. A case study with ejector pins has also been conducted for the demonstration of the proposed method.

Research on Rule-Based Reasoning Intelligent Selection System of Injection Mold Standard Parts

The use of rule-based reasoning technology can realize the intelligent selection of mold standard parts when designing injection mold. In this paper, the selection experience of mold standard parts are stored to databases for scientifically choosing mold base, sprue bushings, ejector pins, and other standard parts. And through the establishment of a rule base, reasoning mechanism, standard parts library, a rule-based reasoning intelligent selection system of injection mold standard parts is proposed and details of the proposed approach are presented.

Machining of micro rotational parts by wire electrical discharge grinding

Micro rotational parts are used in several industrial sectors. Well-known applications are micro shafts of gears, ejector pins in forming tools, pin electrodes for micro electrical discharge drilling or micro stamping dies. Depending on the geometrical complexity of micro rotational parts different process variants of micro electrical discharge machining characterized by a rotating work piece can be used: wire electrical discharge grinding (WEDG) with fine wire electrodes, electrical discharge turning (EDT) with micro structured tool electrode, cylindrical electrical discharge grinding (CEDG) with micro profiled disk electrode. Characteristic to these process variants is the superimposed relative motion between the rotating electrodes and the feed. This relative motion can be varied in a wide circumferential velocity range to improve the material removal process. The paper gives an overview of kinematic and technological restrictions and requirements of the WEDG process influencing the process behavior with respect to the technological requirements of micromachining.

Engineered-to-order Approach for Providing Flexibility in e-Commerce of Mold Parts

In the mold parts industry, customers typically place orders for order-made parts with some changes to the design specifications of ready-made parts within the extent of the manufacturing capability of the supplier. Being customized for ready-made parts, existing e-Catalog systems cannot support this trade pattern. To solve this problem, an engineered-to-order (ETO) approach is proposed here, enabling the trade of order-made parts in an e-Catalog system by utilizing the design and manufacturing knowledge of part suppliers. After addressing technological challenges and their solutions, we describe application results of the ETO approach to two types of mold parts — ejector pins and mold bases.

The Use of the Indentation Test for Studying the Solidification Behaviour of Different Semicrystalline Polymers during Injection Molding

AbstractSummary: An in‐line method for monitoring the solidification process during injection molding of semicrystalline polymers (demonstrated previously in J. Appl. Polym. Sci. 2003, 89, 3713) is based on a simple device, where an additional ejector pin is pushed on the injection molded part at different times during the solidification phase. The ‘indentation depth profile’, i.e., residual deformation as a function of time, was obtained and allowed to determine the evolution of the solidification front in the mold as a function of the cooling time. The present work shows the reliability and the powerfulness of the aforementioned method for a large variety of different semicrystalline polymers (PET, PBT, polyamide‐6 PA6, isotactic poly(propylene) iPP) characterized also by different molecular weight and/or nucleating agents. The results show that the indentation test may be considered as a ‘predictive’ tool to qualitatively and quantitatively compare the solidification process of different polymers and polymer grades during injection molding.Comparison of the solid front propagation during injection molding of different materials.imageComparison of the solid front propagation during injection molding of different materials.

Determination of Die Design Rules for Semi-Solid Die Casting Process and Its Experimental Investigation

Die design rule for semi-solid die casting (SSDC) with A356 electromagnetic stirring (EMS) aluminum alloy, was proposed. The die design rule included inspection of machine, part requirements, parting line determination, sleeve, plunger, gating system, overflow, air vent, ejector pin, and heating line design. The specification of gating system, overflow, air vent, plunger tip, and sleeve suitable for respective part were regulated. Two steps die system of lower-positioned gate and three steps die system of center-positioned gate were manufactured for 4 automobile suspension parts, based on the die design rule. For the sound filling pattern and solidification behavior, injection speeds of 4 parts were summarized to the interval (from V1 to V4). As a result of observing the microstructure of 4 parts after T6 heat treatment, primary Al-α phase was globularized and fine Si particles were distributed around the grain boundary. The mechanical properties of 4 parts with T6 heat treatment were investigated and showed ultimate tensile strength (UTS) of 330 MPa, yield strength (YS) of 250 MPa, and elongation of 7.5% as average.

Prediction of Local Part-Mold and Ejection Force in Injection Molding

A numerical simulation system was developed to predict local part-mold forces and local and total ejection forces in injection molding. Local reaction forces between the part and mold surfaces are calculated first using numerical molding process and structural simulations. Using experimentally obtained coefficients of friction the friction force and ejection force are calculated. Ring moldings were used to measure the coefficient of friction. Box moldings were used to validate predictions of local and total ejection forces and to demonstrate the use of the system in mold design. Calculated ejection force was maximum at the beginning of ejection and differed by 10%–16% from experimental values, with the difference being much less over the main part of the ejection process. The maximum number of ejector pins for failed ejection was predicted. The difference between the predicted and observed number of ejector pins was at most four pins for a twenty ejector pin system.