摆-球“永动” 器结构设计及工艺分析

以提高能源利用率为目的,设计了一种摆-球“永动”器.为了减少能量损失,使单摆来回摆动的时间尽量长,在轨道的选择上,通过对摆线轨道、抛物线轨道和圆弧轨道的效率计算发现,若小球由曲线轨道一侧的最高点开姑下落,计算小球经过最低点后回复到轨道的另外一侧的最高点的高度值,摆线轨迹、抛物线轨迹和圆弧轨迹分别为0.88、0.77和0.61.考虑到三个数值相差不大,通过对加工经济性的分析发现,摆线加工难度大,费用高,圆弧轨道使用普通机床即可达到较好的效果.因此,最终确定圆弧轨道方案.在碰撞过程中为实现能量交换,根据完全弹性碰撞的条件,采用质量相等的两小球.V型槽与小球的接触面积小,能量损失小,小球运动也更加稳固.通过比较摆杆和摆线,发现摆杆的计算误差较大,而选择摆线连接摆球还可以避免使用轴承.实物模型中,当摆球初始速度为0,以摆拉到水平位置为起始位置下落时,摆球碰撞次数为4次,来回摆动时间为12.8 s.

The structure design and the process analysis of the pendulum-ball perpetuum mobile

In order to improve the energy utilization,a pendulum-ball perpetuum mobile is designed in this paper.In order to reduce the energy loss and make the simple pendulum swing back and forth as long as possible,in the selection of the orbit,through the calculation of the efficiency,we find that if the ball begins to fall from the highest point of one side of the curve orbit to the highest point of the other side via the lowest point,the height of the cycloid orbit,the parabolic orbit and the circular arc orbit are respectively 0.88,0.77and0.61.Given that the difference of the three numerical value is not significant,through the analysis of the processing economy of the curve orbit,we find that the machining of the cycloid orbit is more difficult and expensive than the circular arc orbit,and that the latter one can attain good effect through general-purpose machine tool.So we make a comprehensive consideration and determine the circular arc orbit.In order to realize the energy exchange of the ball,we choose two equiponderant balls on the basis of the requirement of perfect elastic collision.The fact that the contact area of the V-groove and the ball is smaller than others means that its energy consumption is smaller.Furthermore,the ball can move more steadily in the V-groove.Comparing the oscillating bar and the string,we find that the computational error of the oscillating bar is larger than the string and that adopting the string can avoid the use of the bearing.When the ball’s initial velocity is 0 in the physical model and pull to put a horizontal position as the starting position whereabouts,the hitting times is four and the time of swing back and forth is 12.8 s.