双联斜齿轮斜齿脱模机构及改进型三板模设计

依据双联斜齿轮和单斜齿轮2个塑件同模注塑的需要,以双联斜齿轮塑件的模腔设计为中心,设计了一副一模两腔点浇口多板模注塑模具。模具中,双联齿轮的上、下斜齿轮斜齿分别使用2个可旋转斜齿轮成型件进行成型;单斜齿轮使用1个可旋转斜齿轮成型件进行成型。3个斜齿成型件设置成转动型成型件,依靠塑件的移动以驱动斜齿成型件转动,达到塑件斜齿脱模的目的;塑件的脱模移动有两种动力来源,一种是模具模板的打开驱动,一种是使用推管顶出驱动。模具为一种改进型三板模结构,定模侧增加了流道板,动模侧增加了垫板,从而可以实现模具的4次开模;4次开模动作中,2次用于流道废料的脱模,1次用于流道镶件的先抽芯驱动,1次用于模腔的打开和双联斜齿轮上斜齿轮的旋转脱模驱动。     

某型柴油机水泵、机油泵间隙调整工装的应用

为了方便某柴油机前端水泵和机油泵齿轮间隙的调整,改变以前传统的调整方法,通过长期在装配现场的观察和了解,设计出某柴油机前端水泵和机油泵齿轮间调整工作,经现场使用验证;该工装安全、小巧轻便精度高,改善了装配的劳动强度和装配质量。     

Conceptualizing “free-from” food consumption determinants: A systematic integrative literature review focused on gluten and lactose

BackgroundGluten- and lactose-free products are registering a sudden rise in the market, particularly among tolerant people, and this leads to consumer confusion and nutritional inadequacies. The number of studies around this trend has steadily increased in the last 10 years, as scholars from different disciplines have tried to rationalize consumers’ behaviours in these foods’ choice. However, the scientific debate appears fragmented and lacks an integrated view.ObjectivesWe conducted a systematic integrative review of consumers’ determinants of gluten-free and lactose-free consumption to frame the state of the art and research gaps.Methods45 English language articles reporting quantitative empirical studies ranging from 1971 and 2019 were analysed. First we categorized the consumption determinants in six factors applying the model proposed by Koster and Mojet, then we proposed a new integrated conceptualization inspired by Bronfenbrenner’s Transtheoretical Model. Moreover, differences and similarities between tolerant and intolerant consumers will be highlighted.ResultsResearch on intolerant consumers focused more on individuals’ determinants, in terms of awareness, trust, morality, and capability to read nutritional facts (as purchase facilitators); while studies targeting tolerant consumers focused more on objective product characteristics (with price and availability in supermarkets as barriers for consumption). In this target the subjective perspective has been studied only referring to the risk for developing psychological issues in the restrictive diet.ConclusionAs information is lacking in the scientific debate, we suggest for future research the integration of consumers’ subjective implicit levers to decipher free-from purchase behaviours.     

Developing social impact assessment guidelines in a pre-existing policy context

Few jurisdictions have translated internationally agreed social impact assessment (SIA) principles into statutory provisions. Governments and regulatory bodies tend to provide developers with high-level frameworks, or require that social impacts be ‘considered’, without specifying how this is to be done. In Australia, this lack of clarity leaves all parties uncertain about requirements for SIA. The New South Wales (NSW) Government’s 2017 release of the SIA guideline for State-significant mining, petroleum and extractive industry development represents an attempt to clarify requirements and provide guidance. In this paper, we describe the process of bringing this guideline to fruition from the perspective of being directly involved in its development, and highlight the challenges involved in integrating leading-practice principles into the state’s pre-existing policy framework. While the guideline represents a significant advance in policy-based SIA guidance, some aspects leave room for improvement. The real test of the guideline’s impact will lie in its influence on SIA practice in NSW, and ultimately in social outcomes for communities affected by resources projects.     

Defining University Anchor Institution Strategies: Comparing Theory to Practice

Since the 1990s, some urban universities have served as neighborhood anchors with an interest in revitalization. Current theory suggests anchors adopt ‘shared value’ approaches, leveraging resources for mutually beneficial improvement in the community. This study explores assumptions in contemporary anchor frameworks and uses a survey to examine how 22 U.S. universities approach their roles as anchor institutions. The study finds that the universities tend to prioritize place-based initiatives, while contemporary frameworks are more normative and highlight socioeconomic practices. Based on reported strategies, the author proposes an alternate typology that accounts for the ways universities most commonly describe anchor approaches, complementing contemporary theory.     

Seeing the bigger picture: Conditions that influence effective engagement of project executives with visuals

This exploratory study provides an influence diagram that shows the network of conditions that influence the use of visuals to effectively engage executives. The diagram was developed from the experiences of project managers and executives elicited through twenty-four semi-structured interviews. Twenty-nine conditions are found to influence the use of visuals to effectively engage executives. These are grouped into four categories: the executive's disposition to the use of visuals; the organisational conditions to create visuals; the project manager's understanding of the executive's information needs; and the executive's and project manager's appreciation of the benefits of using visuals. The study's results highlight that while the interviewed executives had a predisposition to the use of visuals as they are generally time-poor, capability to create visuals to support executive engagement was not widespread. Practical contributions include disclosing the criticality of organisational support for creating visuals and the vulnerability of executives in making project decisions.     

考虑黏压效应的风电齿轮热弹流分析

在线接触热弹流润滑的基础上，考虑黏压效应，对风电行星轮系齿轮副进行热弹流润滑数值分析，并采用热弹流润滑数值方法和ISO/TS 6336-22计算了齿轮副的最小油膜厚度、安全系数和闪温温度，并比较各主要啮合点的压力和油膜厚度分布。结果表明：与使用ISO/TS 6336-22计算的结果对比，采用热弹流润滑理论计算的油膜更厚，但安全系数更小；在风电齿轮副热弹流润滑分析时应考虑压力对黏度的影响；风电主齿轮箱齿面因啮合产生油膜厚度随温度增加会迅速降低，最小油膜厚度会随载荷增加迅速减小，因此风电齿轮箱要保证足够的润滑，并尽量避免在高于额定载荷下长时间持续运行     

2K-H型人字齿周转轮系的免组装设计与成型

为了解决人字齿周转轮系加工、装配的难题,提出利用3D打印技术制造免组装人字齿周转轮系的新工艺。通过理论推导,建立变位系数、齿侧间隙与齿轮基本参数之间的关系。利用建立的关系式,对行星轮进行负变位,设计具有微量齿侧间隙的2K-H型人字齿周转轮系。利用熔融沉积成型实验平台使设计的人字齿周转轮系成型,成型后的人字齿周转轮系齿轮啮合传动正常,设计、制作相应辅件,将其装配成减速步进电机。结果表明,通过合适的间隙设计,可以利用3D打印技术实现人字齿周转轮系的免组装制造,为小尺寸、一体式人字齿周转轮系个性化定制提供了一种具有工业应用前景的全新解决方案。     

齿轮油抗微点蚀试验前后摩擦学性能变化分析

采用MRS-1J四球摩擦试验机、SRV摩擦磨损试验机等考察了齿轮油在抗微点蚀试验前后油品摩擦学性能的变化,采用三维轮廓形貌仪对磨斑表面进行了对比,采用EHD2油膜厚度测定仪考察了油品成膜能力的变化,采用VKA 110四球试验机测试了油品的温升变化情况。结果表明:抗微点蚀试验对齿轮油的组分和抗磨性能基本没有影响,但会造成油品摩擦系数、成膜厚度不同程度下降,同时试验后的油品温升也有一定程度增大。     

转向齿扇多向精密成形工艺

为了降低转向齿扇成形载荷、提高成形模具寿命,通过对转向齿扇的结构特点和工艺性分析,结合多向成形金属流动特点,提出了转向齿扇多向精密成形工艺方案。采用有限元模拟软件DEFORM-3D,对转向齿扇多向精密成形过程进行了数值模拟,对其成形过程中的金属流动规律进行了分析并预测成形载荷。结果表明,成形过程中齿扇充填均匀,角隅充填饱满,多向精密成形工艺最大成形载荷比单向闭塞挤压成形载荷降低了29%,成形时间缩短了53%,有利于提高模具的使用寿命。对多向精密成形工艺进行了成形试验,试验成形出的转向齿扇充填饱满,成形载荷与预测载荷基本一致。试验结果表明了该工艺的可行性和实用性。