弯扭载荷下内套式锥面过盈连接的设计方法

由齿轮啮合等引起的动态附加弯矩对过盈连接的扭矩传递能力具有决定性的影响。文章首先基于Leidich的椭圆准则来计算某牵引电机悬臂式传动端内套锥面过盈连接在弯扭载荷下的抗弛缓能力,接着结合解析方法和有限元方法来计算动态载荷条件下过盈连接的微动滑移区。结果表明,旋转弯矩将使连接的弛缓扭矩大大降低;不发生弛缓条件下,由动态弯扭载荷特别是旋转弯矩引起的微动疲劳将是内套式锥面过盈连接面临的主要风险。设计中应同时满足抗驰缓准则和抗微动疲劳准则,尽量减少连接的旋转弯矩载荷,由工艺油槽等形成的接触边界应避开微动滑移区以避免出现微动疲劳。

Design method of inside fitted conical press-fit connections under bending and torsion load

The attached dynamic bending moment is decisive to the torsion transmission capability of the press-fit connections. Based on the elliptical criteria of Leidich,this paper calculated the sliding torque of the inside fitted conical press-fit in cantilever drive side of a traction motor considering the effects of attached bending moment at first. And then,combined the analytical method and the FEM,the micro sliding zone in the press-fit interface under dynamic torque or bending moment are calculated：it was showed that the attached bending moment greatly reduced the torque transmission capability of the conical press-fit connections; below the sliding torsion, fretting fatigue due to dynamic load,especially rotating bending moment will be the main concern of failure in the press-fit connections. Both of anti-sliding criteria and anti-fretting criteria are should be considered in design, trying to reduce rotating bending moment and shift structures such as oil grooves that create contact edges away from the sliding zone of the press-fit connection in order to avoid fretting fatigue.