29-09-2018, 11:51 PM
Many members get very confused when a mains clock fails to start in the correct direction.
I have found a motor in the timer from a microwave that had a switching failure in the heat rate control.
There is a little clutch that is packed with grease that fits under three little hooks and looks like it is fitted to the gear with circlip pliers during production. It has a long plastic spring with a paddle on the end of it. There is also a peg to stop the flag being pushed down.
The motor pinion has a free wheel like cam below the gear teeth.
In the lower right of the photo you can see the shadow of the parking stop for the flag when the motor is running in the correct direction (antickockwise).
In the next photo you can see the flag close to the stop cam as it would be when the motor is running in the correct direction.
The next photo shows the flag close to the cam on the motor where it will strike the free wheel cam and get compressed until the motor rotation is overcome and the rotor gets sprung to the correct direction of rotation. The grease will provide some viscose resistance to help the spring to compress so generating the energy needed to flick the rotor in the right direction.
Then a general view with the flag mid way between the two positions.
I have found a motor in the timer from a microwave that had a switching failure in the heat rate control.
There is a little clutch that is packed with grease that fits under three little hooks and looks like it is fitted to the gear with circlip pliers during production. It has a long plastic spring with a paddle on the end of it. There is also a peg to stop the flag being pushed down.
The motor pinion has a free wheel like cam below the gear teeth.
In the lower right of the photo you can see the shadow of the parking stop for the flag when the motor is running in the correct direction (antickockwise).
In the next photo you can see the flag close to the stop cam as it would be when the motor is running in the correct direction.
The next photo shows the flag close to the cam on the motor where it will strike the free wheel cam and get compressed until the motor rotation is overcome and the rotor gets sprung to the correct direction of rotation. The grease will provide some viscose resistance to help the spring to compress so generating the energy needed to flick the rotor in the right direction.
Then a general view with the flag mid way between the two positions.
