One afternoon, I rode my bike from west to east and came to a crossroads. Because there is no building nearby, the strong sunlight shines directly on the traffic lights, and I can't tell whether it is a red light or a green light. This is obviously a hidden danger of traffic safety. So I came up with the idea of improving the traffic lights.
Although the traffic lights used now also have hoods, they don't work when the incident angle of sunlight is very low in the morning or before dusk. At this time, the direct sunlight produces strong reflection on the lamp surface, which interferes with the observation signals of drivers and pedestrians. Inspired by blinds, I tried to install a grating multi-layer hood in front of the lamp. The upper surface of the partition was coated with black light-absorbing material, and the lower surface was coated with high reflectivity material. In this way, the sunlight obliquely above is absorbed by the upper surface of the partition, and the signal lamp is black when it is not on; When the light is on, in addition to directly shining out, some light is reflected by the lower surface of the partition, which is easy to be seen by drivers and pedestrians.
I made a traffic light model to prevent sunlight from interfering. Use discarded CD discs as partitions, put black post-it notes on the upper surface, and then use spotlights to simulate sunlight for experiments. When the angle of the sun is 40, part of the surface of the ordinary signal lamp is illuminated, but when the spotlight is directed at an angle close to 0, I can still clearly tell whether the signal lamp is on or not from the perspective of pedestrians.
Invention: New Wrench
Once, I want to change the tire of my bike and ask my father to change it for me. My father brought a toolbox and found M8, M6, M5 and M4 wrenches from many wrenches. Because of the complicated structure of bicycle, it is very troublesome to tighten screws with wrench. Swinging from side to side for a long time, some screws are still not tightened. Dad had to try again and finally finished, but he was sweating like a pig. After reading it, I thought: Is there any way to change the use principle of wrench and make it more convenient and equipped with a variety of wrenches?
In the summer vacation, we learned something about invention. Once, the teacher introduced a double-headed screwdriver in class, and it suddenly occurred to me that I wanted to be a multi-purpose wrench. I can choose from a variety of wrenches, which can be vertically rotated and used on movable handles and handrails. Under the guidance of my teacher, I made a multi-purpose wrench by myself, combining some knowledge I learned in the invention class and the method theory I saw in some materials. This kind of wrench can choose four kinds of wrench heads and fix them on the movable handle and armrest with iron rings. Four kinds of wrenches can rotate freely. The handle can be placed vertically, with fast rotation speed and time saving. But also can be placed horizontally, and the torsion force is large when in use.
This work has the following three advantages:
L) Vertical placement: when the screw is put in or loosened and screwed out, the force is not great, so the rotatable movable handle can be placed vertically, with one hand holding the handrail and the other hand rotating the handle quickly. At this time, the strength is extremely small, and the screw can be quickly unscrewed in an instant.
2) Horizontal placement: Under the condition of constant force, changing the torque distance-lengthening can increase the torque. Used for clamping or the moment when the screw is forcibly loosened after clamping.
3) There are four specifications to choose from, and there is no need to change them, just rotate them to the required specifications. The four specifications are connected as a whole and should not be lost.
Invention: Fluorescent lamp cleaner
When cleaning the classroom, the most difficult thing to deal with is the fluorescent tube, which is installed at the height of the ceiling. Only by putting up a ladder or stacking tables and chairs high can you get there, but it is still inconvenient and dangerous to scrub.
Once, a spark of invention flashed in my mind: a gadget that can clean fluorescent lamps without climbing very high should be designed and manufactured. I found a big beverage bottle, cut off a section with a bottle mouth, the height is about 15cm, and cut a U-shaped notch on both sides of the section with scissors, the width is slightly larger than the diameter of the fluorescent tube: Next, put a sponge in the bottle and stick it firmly. Finally, find a stick with the same diameter as the bottle mouth, insert it into the bottle mouth and nail it firmly. An eye washer is ready.
The use method is simple: lift the vacuum cleaner, aim the U-shaped notch at the fluorescent tube, and move it back and forth several times, so that the dust on the tube will be wiped clean. The sponge of the washing machine can also be washed with water.