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教学中,无论是分析杠杆的平衡,还是认识杠杆省力与费力,我们使用的是传统的杠杆尺。其附有可以移动的挂钩,容易滑落,稳定性差;两端伸出用于调节平衡的螺丝、螺母,学生使用时不够安全。怎样让杆尺下挂钩的位置既可移动又能固定?能否移去杠杆两端的平衡螺丝、螺母?我在旋钮式美工刀上得到了启发。采用一根500mm×23mm×10mm“H”形含上下槽的铝合金材料做杆体。在杆体槽内中心处钻一个?4mm小孔。再取3只6mm×10mm×8mm长胶头
Teaching, whether it is to analyze the balance of the lever, or to understand the lever effort and effort, we use the traditional lever. It is attached to a removable hook, easy to slip, poor stability; both ends of the balance for the adjustment of the screws, nuts, students are not safe enough to use. How to make the position where the rod is hooked can move and fix? Can you remove the balance screw and nut at both ends of the lever? I got the inspiration on the knob-type utility knife. Using a 500mm × 23mm × 10mm “H” shape with the upper and lower slot aluminum alloy rod. Drill a 4mm hole in the center of the rod body. Then take three 6mm × 10mm × 8mm long plastic head