余弦形负载超声变幅杆的设计与研究

The Characteristics of cosine type Loaded ultrasonic horn

研究余弦形负载超声变幅杆特性。求解了加负载时四种超声变幅杆的输入阻抗,得到加负载时输入阻抗和Mbius变换参数的统一算式。当变幅杆的输入抗分量为零时,计算了余弦形负载变幅杆的纵向振动共振频率方程和放大系数。由输入阻抗的表达式讨论了此类变幅杆的工作稳定性条件和相对阻抗相等点。结果表明由两种方法计算的共振频率方程是相同的;余弦形变幅杆的各种参量和方程与负载阻抗紧密相关;有负载力阻时1/4波长变幅杆的放大系数要比1/2波长变幅杆显著的多,和杆两端特性阻抗的几何平均值成正比,而与负载力组成反比。

This paper studies a cosine type loaded ultrasonic hom. The unified expressions of anplification factor and moebius transformation parameters of four kinds of loaded transformers are given. If the input reactance part of uhrasoalc horn is zero, the resonance frequency equation and magnification coefficient of loaded cosine longitudinal ultrasonic hom will be calculated, including pure resistance and pure reactance and impedance, Based on the expression of moebius transformation, the working stability of this type of transformer and equal point of relative impedance etc are further discussed. It shows that resonance frequency equation of loaded cosine horn with two above methods are the same; Its parameters and frequency equation have a close relation with load impedance in relation to zero load horn; In pure resistance condition, magnification coefficient of one - fourth wavelength transformer is more obvious than that of half- wavelength horn, which varies directly with geometric mean value of input impedances of both sides, whereas, varies inversely with pure resistance load.