本文選題：深孔加工　切入點：直線度誤差　出處：《中北大學》2015年博士論文　論文類型：學位論文

【摘要】：隨著市場經濟對制造業(yè)發(fā)展的多樣性要求，機械零部件產品正以高效率、低成本的形式展現(xiàn)在人們面前；作為制造業(yè)的重要組成部分，深孔加工正面臨著小批量、多品種、異型孔、新型材料、高難度及越來越高精度要求的挑戰(zhàn)。深孔加工由于其特有的加工難點和使用要求，如何獲得在尺寸精度、圓度、直線度、圓柱度和粗糙度等方面都很高精度的深孔，長期以來一直是人們最為關注的熱點問題。在深孔加工過程中，深孔軸線容易發(fā)生偏斜，當偏斜發(fā)展到一定程度后，深孔加工的直線度就開始急劇惡化，人們采用了提高機床、工裝、刀具精度和剛度等多種方法改善深孔加工直線度誤差，但是到目前為止尚未得到很好的解決。故此，本文基于流體動力潤滑理論，從深孔加工切削液流體動力特性、切削液對BTA旋轉鉆桿的動態(tài)干擾、切削液流體的入口壓力特性及深孔加工直線度誤差的測量等方面，研究深孔加工直線度。主要研究內容如下： （1）針對深孔加工過程中旋轉鉆桿受到切削液流體力的特點，依據流體Reynolds方程及鉆桿彎曲變形、傾角方程，建立了深孔加工直線度誤差方程，揭示了切削液流體入口壓力、鉆桿轉動、渦動、擠壓、鉆桿結構參數(shù)與深孔直線度之間的關系。指出在切削穩(wěn)定狀態(tài)下，減小切削液入口壓力，增加鉆桿轉速、減小鉆桿渦動速度或者減小鉆桿擠壓速度等均可改善深孔直線度誤差。 （2）深孔加工過程中，負壓結構的工作參數(shù)對切削液入口壓力有很大的影響，，包括噴射系數(shù)、排屑口的橫截面積比、排出壓力、負壓級數(shù)等。噴射系數(shù)和排屑口的橫截面積比呈非線性正比關系，負壓排出壓力隨入射壓力的增大而增大，增加負壓級數(shù)對降低切削液入口壓力、改善排屑效果及提高深孔加工直線度精度有很好的作用。通過模擬切削液的運動形態(tài)，研究切削液在流動中能量的損失，發(fā)現(xiàn)曲面噴嘴的負壓效果優(yōu)于錐面噴嘴，多級負壓結構優(yōu)于單級負壓結構。 （3）設計了新型多級負壓結構，其通過增設分流腔和增加噴射級數(shù)來降低切削液入口壓力，可有效減小深孔直線度誤差；闡述了SFD利用油膜阻尼力減小深孔鉆桿的渦動與擠壓運動，來提高深孔加工直線度。得出了多級負壓結構、共同作用下的深孔直線度誤差，試驗驗證了鉆桿在較低切削液流體入口壓力、較小渦動和擠壓作用下加工的深孔有更好地直線度，為控制深孔加工直線度誤差提出新的思路及方案。 （4）基于光電原理，提出了一種利用輸出電壓的變化規(guī)律來準確測量深孔直線度的方法。分析了光電探測器發(fā)生平移運動和旋轉運動時造成的實際孔中心位置的變化規(guī)律�；谧钚《嗽恚茖Я松羁字本�度與輸出電壓的關系，為深孔直線度光電測量提供了理論基礎。利用光電測量原理，設計了一種具有自定位功能、實時顯示深孔直線度誤差的光電測量裝置，可實現(xiàn)深孔直線度的無損自動檢測。
[Abstract]:With the diversity of market economy to the development of manufacturing industry, machinery products and parts with high efficiency, low cost in the form of the show in front of people; as an important part of the manufacturing industry, deep processing is facing many varieties, small batch, special-shaped hole, new materials, high difficulty and high accuracy requirements of more and more challenges. The deep hole processing requirements for processing and using the unique difficulties, how to obtain the precision in size, roundness, straightness, roundness and roughness on high precision deep hole, a long time has been a hot issue of concern to most people. In the process of deep hole processing, deep hole axis prone to deviation, when the deviation to a certain extent, the deep processing of straightness began to rapidly deteriorate, people used to improve machine tools, tooling, cutting precision and rigidity of a variety of methods to improve the deep processing of straightness error, but to So far hasn't been solved well. Therefore, this paper based on the theory of hydrodynamic lubrication, the dynamic characteristics of deep hole machining cutting fluid, dynamic interference of cutting fluid on BTA rotary drill, measurement etc. the entrance pressure characteristics and deep processing of straightness error of cutting fluid, research on deep processing of straightness. The main research contents the following:
(1) according to the characteristics of rotary drill deep hole machining process by cutting fluid flow force, based on fluid Reynolds equation and the bending deformation of the drill rod, angle equation, an equation of the deep hole processing of straightness error reveals the cutting fluid entrance pressure, drill pipe rotation, eddy, extrusion, the relationship between the drill pipe structure parameters and deep hole straightness the cutting. Pointed out that in the steady state, reducing cutting fluid entrance pressure, increasing the rotation speed of the drill pipe, drill pipe to reduce eddy velocity or decreasing extrusion speed can improve the drill hole straightness error.
(2)娣卞瓟鍔犲伐榪囩▼涓

本文編號：1644551