定值補償液靜壓軸承的靜剛度設計

Design for Stiffness of Hydrostatic Plane Bearings：Constant Compensation

黃慶初(Ching-Chu Huang)

指導教授 ： 張永鵬 ； 康淵

中原大學/工學院/機械工程研究所/博士(2010年)

https://doi.org/10.6840/cycu201000629

摘要

摘要

為了設計出可接受和最佳化的液靜壓軸承特徵，補償類型的選擇以及參數的確定非常重要。本文利用流量平衡方程式來確定相對於油腔壓力的薄膜厚度或工作台位移。透過單補償器或雙補償器分別對開及閉式液靜壓軸承的油腔壓力加以控制，由相對於工作台位移的不同油腔壓力即可確定靜剛度係數。本文對定流泵、毛細管節流器以及孔口節流器這三種類型的穩定補償都進行了探討。
研究結果顯示，透過對油腔壓力和補償參數範圍的選擇，可得到與之相對應的工作台位移或薄膜厚度的最小變化梯度。三種補償方式下薄膜厚度相對於油腔壓力比率的變化，可透過油墊節流參數與厚度比率立方的乘績來評估。在具有相同的軸承節流參數、負荷以及供應壓力時，由定流泵導致的薄膜厚度要大於使用孔口和毛細管時的薄膜厚度。因此使用定流泵可得到比使用孔口和毛細管有更好的梯度。由定流泵補償導致的剛度會隨著油腔壓力的增加而相應增大；在具有相同的油腔壓力比率時，使用定流泵進行補償，與使用孔口補償和毛細管補償相比，可以獲得更大的剛度。

關鍵字

靜剛度 ； 液靜壓軸承 ； 定值補償

並列摘要

Abstract

The type selection and parameters determination of the compensation are most important for yielding the acceptable or optimized characteristics in design of hydrostatic bearings. This study utilizes the equations of flow equilibrium to determine the film thickness or displacement of worktable with respect to the recess pressure. For both open-type and closed-type hydrostatic plain bearings their recess pressures are controlled respectively by single compensator or double compensations, the statics stiffness coefficient can be determined by differentiating the recess pressure with respect to worktable displacement. Three constant compensations in type of constant-flow pump, capillary restrictor and orifice restrictor are taken into consideration in this study.
The finding results give that the usage range of recess pressure and compensation parameters can be selected to correspond to the smallest gradient in variations of worktable displacement or film thickness. Alternatively, the variations of film thickness with respect to the recess pressure ratio can also be evaluated by the products of pad restriction and cube of thickness ratio which are determined for three compensations. That the film thickness due to constant-flow pump is larger than that of orifice and larger than that of capillary as they having identical restriction of bearing pad and both the same load and supply pressure. The largest roughness of bearing pad can be allowed by constant-flow compensation due to the largest film thickness. Also, it can be shown that the gradient due to constant-flow pump is better than that of orifice and better than that of capillary as they having identical restriction of bearing pad. The stiffness due to compensation of constant-flow pump increases monotonically as recess pressure increasing. Also, which is larger than that due to orifice compensation and larger than that due to capillary compensation at the same recess pressure ratio.

並列關鍵字

Hydrostatic Plane Bearings ； Static Stiffness ； Constant Compensation

參考文獻

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