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s not needed. Instead, he plans to deploy his 270squarefoot (25squaremeter) main chute at an altitude of around 5,000 feet (1,524 meters). In order to deploy this chute successfully, he will have to slow to 172 mph (277 kph). He will have a reserve parachute that will open automatically if he loses consciousness at mach speeds. Even if everything goes as planned, it won39。 3. Ask your heart what it wants 傾聽內(nèi)心 We’re often confused at the next step to take, making pros and cons lists until our eyes bleed and our brains are sore. Instead of always taking this approach, what if we engaged a new part of ourselves that isn’t usually involved in the decision making process?我們常對未來猶疑不定,反復(fù)考慮利弊直到身心俱疲。 2. Embrace the unfortable We all know what that twinge of anxiety feels like. We know how fear feels in our bodies: the tension in our necks, the tightness in our stomachs, etc. We can practice leaning into these feelings of disfort and let them show us where we need to go.我們都經(jīng)歷過焦灼的煎熬感,也都感受過恐懼造成的生理反應(yīng):脖子僵硬、胃酸翻騰。下面六個(gè)方法有助于你更完滿透徹地敞開心扉。 Baumgartner the disappointing news: Mission aborted. r plays an important role in this mission. Starting at the ground, conditions have to be very calm winds less than 2 mph, with no precipitation or humidity and limited cloud cover. The balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our daytoday weather lives. It will climb higher than the tip of Mount Everest ( miles/ kilometers), drifting even higher than the cruising altitude of mercial airliners ( miles/ kilometers) and into the stratosphere. As he crosses the boundary layer (called the tropopause),e can expect a lot of turbulence. We often close ourselves off when traumatic events happen in our lives。 From the corner at the beginning of deep friendship。嫌惡過自己的怯懦,最終卻發(fā)現(xiàn)有很多 緣分 ,有很多錯(cuò)過,好像冥冥之中真的已經(jīng)注定。 A person39。 Then in high school, think don39。二十年的人生軌跡深深淺淺,突然就感覺 到有些事情,非做不可了。s plaint. In a statement the Russian side added: We found no racist insults from fans of CSKA. Age has reached the end of the beginning of a word. May be guilty in his seems to passing a lot of different life became the appearance of the same day。s about how he felt and I would like to speak to him first to find out what his experience was. Uefa has opened disciplinary proceedings against CSKA for the racist behaviour of their fans during City39。re clear about the terms of the agreement. It might be best to get advice from an experienced adviser, for example, at a Citizens Advice Bureau. To find your nearest CAB, including those that give advice by , click on nearest CAB. For more information about making a claim to an employment tribunal, see Employment tribunals. The (lack of) air up there Cay man Islandsbased Webb, the head of Watch m Fifa39。 11 模具工作過程 模具裝配試模完畢之后(見總裝圖),模具進(jìn)入正式工作狀態(tài),模具基本工作過程如下 : ( 1) 對塑料進(jìn)行烘干,并裝入料斗; ( 2) 清理模具,并進(jìn)行適當(dāng)?shù)念A(yù)熱; ( 3) 合模、鎖緊模具; ( 4) 對塑料進(jìn)行預(yù)塑化,注射裝置準(zhǔn)備注射; ( 5) 注射,其過程包括充模、保壓、倒流、澆口凍結(jié)后的冷卻和脫模; ( 6) 脫模過程: 當(dāng)注射機(jī)開模時(shí), 中間板先與定模板分離,脫 ag an employment tribunal clai Emloyment tribunals sort out disagreements between employers and employees. You may need to make a claim to an employment tribunal if: you don39。 24 ( 3) 承受一定的側(cè)向壓力 塑料熔體在充型過程中可能產(chǎn)生單向側(cè)壓力,或者由于成型設(shè)備精度低的影響,使導(dǎo)柱承受了一定的側(cè)向壓力,以保證模具的正常工作。 本塑件為小型制件, 厚度較小,同時(shí)由于模具結(jié)構(gòu),故本設(shè)計(jì)冷卻水道只在中間板上開設(shè)兩個(gè),如圖 91 所示。 ( 3) 澆口 處加強(qiáng)冷卻 塑料熔體 充型時(shí),澆口附近溫度最高,距澆口越遠(yuǎn)溫度越低,因此澆口附近應(yīng)加強(qiáng)冷卻,通常將冷卻水道的入口處設(shè)置在澆口附近,使?jié)部诟浇哪>咴谳^低溫度下冷卻,而遠(yuǎn)離澆口部分的模具在經(jīng)過一定程度熱交換后溫水作用下冷卻。注射模具中設(shè)置溫度調(diào)節(jié)系統(tǒng)的目的,就是要 通過控制模具溫度,使注射成型具有良好的產(chǎn)品質(zhì)量和較高的生產(chǎn)效率。 ( 3)模具的開模行程 S=H1+H2 =15+40 =55mm250mm,校核合格。 經(jīng)上述尺寸確定,模架尺寸已 改裝后的模架形式如圖 71所示。 根據(jù) 《塑料模具設(shè)計(jì)指導(dǎo)(第 2 21 版)》表 73簡化 點(diǎn)澆口模架組合形式(摘自 GB/T125552022) 可確定選用簡化點(diǎn)澆口 JA型, 由于模具形式為瓣合形式,所以 模架中的導(dǎo)柱采用反裝形式, 復(fù)位桿位置也有所改變 。 ( 2) 楔緊塊 的楔角:模具在合模時(shí),為了使滑塊能 夠復(fù)位, 鎖緊,其 楔角 應(yīng)等于滑塊楔角,為 30176。 澆口凝料開模行程 H2,考慮到模具結(jié)構(gòu)及加工,而且塑件加工批量不是很大,本設(shè)計(jì)澆口凝料采用手工取出。 本設(shè)計(jì)的抽芯距如圖66所示。 圖 63 滑塊 滑塊 導(dǎo)滑形式的確定 考慮到綜合機(jī)械加工因素,本設(shè)計(jì)采用“ T”形導(dǎo)滑塊進(jìn)行導(dǎo)滑,其結(jié)構(gòu)如圖 64所 19 示。左右。 滑塊的設(shè)計(jì) 滑塊是側(cè)向型芯(小型芯)的安裝和固定的基本或者是部分側(cè)向型腔,在模板和和壓塊構(gòu)成的導(dǎo)滑槽中滑動(dòng),要求滑動(dòng)靈活,感覺無明顯間隙而又不會(huì)有卡滯現(xiàn)象。 根據(jù)動(dòng)力來源的不同,側(cè)向分型與抽芯機(jī)構(gòu)一般可分為機(jī)動(dòng)、液壓(液動(dòng))或氣動(dòng)以及手動(dòng)等三大類。 6 側(cè)向分型與抽芯機(jī)構(gòu)的設(shè)計(jì) 當(dāng)注射成型側(cè)壁帶有孔、凹穴、凸臺等塑料制件時(shí) 模具上成型該處的零件就必須制成側(cè)向移動(dòng)的零件,以便 在脫模之前先抽掉側(cè)向成型零件,否則就無法脫模。由于滑輪軸肩高度很小,且塑件冷卻后會(huì)收縮,因此脫模力極小,推桿足夠推出塑件 。圓形結(jié)構(gòu)簡單,應(yīng)用最廣。為了避免細(xì)長桿變形,對于直徑為 以下的推桿最好設(shè)計(jì)成階梯形。推桿推出機(jī)構(gòu)的特點(diǎn):推桿加工簡單,更換方便,脫模效果好。 (5)合模時(shí)的正確復(fù)位。 (3)機(jī)構(gòu)簡單、動(dòng)作可靠。為了保證塑件在推出過程最后不變形、 不 損壞 ,設(shè)計(jì)時(shí)應(yīng)仔細(xì)分析塑件對模具包緊力和黏附力的大小,合理的選擇推出方式和推出位置。 (1)推出機(jī)構(gòu)應(yīng) 盡量設(shè)在動(dòng)模一側(cè)。 型腔側(cè)壁厚度計(jì)算公式為 : S=r ? ?? ? ???????? ?? 12 P? ? (式 43) 式中 S —— 型腔側(cè)壁厚度( mm) r —— 型腔內(nèi)半徑 ( mm) ,在此取最大半徑 r= ??? —— 材料許用應(yīng)力 ( MPa) , ??? = s? /ns( s? 為材料屈服點(diǎn), 40Cr 的屈服點(diǎn)為s? =784MPa, ns為 安全系數(shù),通常取 ~ ,在此取 ,得 ? ?? = s? /ns=784/2=392MPa P —— 型腔內(nèi)塑料熔體 壓力( MPa) , 查《塑料模具設(shè)計(jì)指導(dǎo)(第 2 版)》表 22常用塑料注射成型時(shí)型腔平均壓力 ,取 P=25( MPa) 將各數(shù)據(jù)代入公式求得 S=,本設(shè)計(jì)最小側(cè)壁厚度 S=5mm,滿足要求。 mm Cs4=177。 =? mm, 相應(yīng)塑件制造公差△ 3= 計(jì)算公式為 : (LM)0 +δ z=[(1+Scp)lsx△ ] (式 41) 式中是塑件平均收縮率,塑件平均收縮率為 1%~ %,所以其平均收縮率 Scp=( +) /2=(下同) ; X是系數(shù),查《塑料模具設(shè)計(jì)指導(dǎo)(第 2版)》表 210,取 X1=, 2=, X3=;△是塑件相應(yīng)尺寸的公差;δ z是塑件上相應(yīng)尺寸制造公差,查《塑料模具設(shè)計(jì)指導(dǎo)(第 2 版)》表 211,取δ z1=, δ z2=, δz3=。 圖 41型腔 結(jié)構(gòu) 組合形式 成型零件工作尺寸的計(jì)算 塑件精度等級按塑件公差數(shù)值表( GB/T 144861993),取 MT5級,計(jì)算中按相應(yīng)公差來查取,采用平均值法來計(jì)算。根據(jù)對成型塑件的綜合分析,該塑件的成型零件要有足夠的剛度、強(qiáng)度、耐磨性及良好的抗疲勞性。(包括矩形