發(fā)布時間：2018-04-20 23:02

  本文選題：直齒圓柱齒輪 + 冷擠壓��； 參考：《重慶大學(xué)》2016年博士論文

【摘要】：直齒圓柱齒輪作為載重汽車輪邊減速器中最常見的傳動零件,市場需求量巨大,一般采用切削加工方法制造。隨著精密塑性成形工藝的發(fā)展,直齒圓柱齒輪的生產(chǎn)也越來越多的采用這種凈近成形的方法制造,其成形后的齒面光潔,金屬流線連續(xù),輪齒承載能力高,因此采用精密塑性成形工藝制造直齒圓柱齒輪具有廣闊的應(yīng)用前景。隨著模具制造技術(shù)的提高和新型模具材料的研發(fā)及應(yīng)用,大模數(shù)、大齒寬直齒圓柱齒輪精密塑性成形技術(shù)正逐漸應(yīng)用于工業(yè)生產(chǎn),但仍存在成形質(zhì)量不穩(wěn)定、成形精度差的問題。因此,如何提高直齒圓柱齒輪的成形質(zhì)量和成形精度是精密塑性工藝的關(guān)鍵。本文以載重汽車輪邊減速器用直齒圓柱齒輪為研究對象,提出一種全新的直齒圓柱齒輪通過式連續(xù)“冷擠壓+冷整形”復(fù)合成形工藝方案,并從直齒圓柱齒輪冷擠壓工藝參數(shù)多目標(biāo)優(yōu)化、大模數(shù)冷擠壓直齒輪冷整形方式和整形量的選擇、直齒圓柱齒輪冷擠壓組合凹模的優(yōu)化設(shè)計等方面對直齒圓柱齒輪通過式連續(xù)“冷擠壓+冷整形”復(fù)合成形關(guān)鍵技術(shù)進(jìn)行了系統(tǒng)全面的研究。論文的主要研究工作有以下幾點(diǎn):(1)對原成形工藝通過式冷擠壓生產(chǎn)的直齒圓柱齒輪成形質(zhì)量差、成形精度低的問題進(jìn)行了分析,得出導(dǎo)致成形齒輪質(zhì)量差、精度低的主要原因?yàn)?冷擠壓時背壓力不足和冷擠壓齒輪的彈性回復(fù)。基于分析結(jié)果提出一種全新的直齒圓柱齒輪通過式連續(xù)“冷擠壓+冷整形”復(fù)合成形工藝。(2)研究分析了冷擠壓主要工藝參數(shù)對直齒輪成形質(zhì)量的影響規(guī)律,提出采用數(shù)值模擬和實(shí)驗(yàn)設(shè)計相結(jié)合的方式,以響應(yīng)面法作為優(yōu)化方法,成形質(zhì)量和成形載荷作為優(yōu)化目標(biāo),對各工藝參數(shù)進(jìn)行多目標(biāo)優(yōu)化設(shè)計,得出最佳工藝參數(shù)組合。誤差分析和生產(chǎn)實(shí)踐證明,采用優(yōu)化工藝參數(shù)組合,能有效提高齒輪成形質(zhì)量和降低齒輪成形載荷。(3)基于冷擠壓齒輪實(shí)際測量的數(shù)據(jù)建立誤差模型,分析了不同冷整形方式及整形量對齒輪冷整形過程中金屬流動及齒輪精度的影響規(guī)律,并確定了合理的冷整形方式及整形量。采用只整形齒面的冷整形方式和雙側(cè)整形量為0.15mm進(jìn)行工藝實(shí)驗(yàn),檢測結(jié)果顯示,齒輪齒形精度由8級提高至7級,齒向精度由10級提高至8級,冷整形工藝可以顯著地提高冷擠壓齒輪的精度。(4)采用實(shí)驗(yàn)設(shè)計與數(shù)值模擬相結(jié)合的方法,構(gòu)建直齒圓柱齒輪冷擠壓組合凹模結(jié)構(gòu)參數(shù)與模芯最大等效應(yīng)力之間的Kriging模型,運(yùn)用粒子群算法對其進(jìn)行全局尋優(yōu),得出冷擠壓組合凹模最佳直徑比和過盈系數(shù)。優(yōu)化后的組合凹模整體尺寸僅為經(jīng)驗(yàn)法設(shè)計尺寸的68.75%,有效減小了組合模具的整體尺寸,節(jié)約了模具材料,采用優(yōu)化后的組合凹模進(jìn)行實(shí)際生產(chǎn),模具使用壽命約15萬件,與原經(jīng)驗(yàn)法設(shè)計的組合凹模相比較,使用壽命保持不變。(5)采用直齒圓柱齒輪通過式連續(xù)“冷擠壓+冷整形”復(fù)合成形工藝進(jìn)行生產(chǎn)試制,尺寸檢測結(jié)果顯示,上、下端齒頂最小直徑分別為74.40mm和73.86mm,均達(dá)到后續(xù)車外圓要求,下端端面外凸約2mm,上端端面凹陷約2mm,優(yōu)于原工藝加工的齒輪。齒輪精度檢測結(jié)果顯示,齒廓總偏差最大為12.2μm,達(dá)到了GB/T10095齒形精度等級6級;螺旋線總偏差最大為26.6μm,達(dá)到了GB/T10095齒向精度等級8級。因此采用復(fù)合成形工藝可以加工生產(chǎn)出精度為8級的大模數(shù)直齒圓柱齒輪。
[Abstract]:As the most common transmission part in the wheel side reducer of the truck, the straight tooth cylindrical gear has a huge market demand, which is usually made by cutting method. With the development of the precision plastic forming technology, the production of the straight tooth cylindrical gear is also more and more manufactured by this net forming method. The tooth surface after forming is smooth and metal. With the continuous flow line and the high bearing capacity of the tooth, the precision plastic forming technology has a broad application prospect. With the improvement of the mould manufacturing technology and the development and application of the new mold material, the large modulus and the large tooth wide straight cylindrical gear precision plastic forming technology is gradually applied in the industrial production, but still remains. Therefore, how to improve the forming quality and forming precision of the spur gear is the key to improve the forming quality and forming precision of the spur gear. In this paper, a new type of straight spur gear continuous "cold extrusion + cold shaping" is put forward by using the spur gear of the wheel side reducer of heavy truck as the research object. "Compound forming process plan", and from the cold extrusion process parameters optimization of straight tooth cylindrical gear, the selection of cold extrusion method and plastic volume of large modulus cold extruding spur gear and the optimization design of cold extrusion die for straight tooth cylindrical gear, the key technology of the continuous continuous "cold extrusion + cold shaping" of straight tooth cylindrical gear is made. The main research work of the paper is as follows: (1) the problems of poor forming quality and low forming precision of the straight tooth cylindrical gear produced by the cold extrusion of the original forming process are analyzed, and the main reasons for the poor quality of the forming gear and the low precision are the insufficient back pressure and cold extrusion in the cold extrusion. Based on the analysis results, a new process of continuous "cold extrusion + cold shaping" composite forming for straight spur gear is proposed. (2) the influence of the main process parameters on the forming quality of the spur gear is studied and analyzed, and a combination of numerical simulation and experimental design is proposed, and the response surface method is adopted. As optimization method, forming quality and forming load are the optimization targets, the optimum design of various process parameters is carried out, and the optimum combination of process parameters is obtained. Error analysis and production practice prove that the optimization of process parameters can effectively improve the quality of gear forming and reduce gear forming load. (3) based on the practice of cold extruded gear. The error model of the measured data is set up. The influence of different cold shaping methods and plastic volume on the metal flow and gear precision in the cold shaping process of the gear is analyzed. The reasonable cold shaping method and the plastic volume are determined. The cold shaping method and the bilateral plastic volume of the tooth surface are used for the process experiment of 0.15mm, and the test results are shown, The precision of gear tooth shape is raised from 8 to 7, and the precision of tooth direction is raised from 10 to 8. Cold shaping technology can improve the precision of cold extruded gear. (4) the Kriging model of the structure of the cold extrusion die of the straight spur gear and the maximum equivalent stress of the core is constructed by combining the experimental design with the numerical simulation. The optimum diameter ratio and interference coefficient of the combined die for cold extrusion are obtained by the particle swarm optimization. The overall size of the combined die after the optimization is only 68.75% of the design size of the experience method, which effectively reduces the overall size of the combined die, saves the mold material, and uses the optimized combined die to make the actual production, the die makes the die. Compared with the combined die designed by the original experience method, the service life remains unchanged. (5) the production test is made by the continuous "cold extrusion + cold shaping" composite forming process of straight tooth cylindrical gears, and the size detection results show that the minimum diameter of the upper and lower teeth is 74.40mm and 73.86mm respectively, which all reach the outside of the vehicle. The end face is convex about 2mm, and the end face is convex about 2mm, the end face of the upper end is about 2mm, which is better than the original process gear. The gear precision test results show that the maximum tooth profile deviation is 12.2 u m, reaching the 6 grade of GB/T10095 tooth shape precision grade; the maximum spiral line deviation is 26.6 mu m, and the GB /T10095 tooth direction precision grade is 8. It can produce a large modulus spur gear with a precision of 8.

【學(xué)位授予單位】：重慶大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2016
【分類號】：TH132.41;TG376.3

【引證文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 冉力;載重汽車用直齒圓柱齒輪冷擠壓模具強(qiáng)度及壽命研究[D];重慶理工大學(xué);2017年

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本文編號：1779816