Image 1 This is a watch. It uses gears, as seen in the image. The gears allow the ratio of seconds to minutes to hours to 12-hours to be consistent, and thus, the time would be accurate.
Image 2 This is a clothes peg. It is a first class lever, as seen in the image. Little effort applied is able to open up the peg, which is held shut by the spring. The spring holds the clip in place when no effort in applied.
Image 3 This is a light switch. It uses cams. Many light switches have a cam surface in them to provide a snap action — a spring applies pressure and once past the high point of the cam, pushes the switch to a notch. This not only keeps the switch in its position, but also allows the user to not need to flick the switch all the way.
Image 4 This is linkages used to support a wall lamp. The extension from the walls is adjustable while allow the lamp to be parallel to the wall.
The umbrella is a troublesome tool, yet ever so frequently used in Singapore. When it is raining and people are getting into their cars, the conventional umbrella design forces the user to hold the umbrella high up to close it, before getting into the car. This makes people very wet eventually, which defeats the purpose.
The reversed umbrella closes inwards — the opposite way, which means that the user can close the umbrella while pulling it into the car. Also, when it closes inwards, the water is trapped in the umbrella, not outside, which allows the inside of vehicles to stay dry. Thus, it is perfect for bringing around indoor buildings. This also saves plastic bags issued for wet umbrellas.