Meccano Gearbox

The gearbox is a whirling, spinning plethora of gears densely packed into a relatively frugal framework. Despite not actually doing anything, it can be captivating to watch it frantically go through its cyclic motions. A myriad of gears all turning in different directions and orientations with varying velocities catches and holds the eye.

See if you can work out the gearing paths from motor to dial, they twist and turn and cross themselves.

I usually include a card asking five questions when this is displayed:

1/ How many gears are present?
2/ Where is the differential?
3/ Where are the two dwell producing mechanisms?
4/ Which two gears aren't essential?
5/ What kind of gear isn't present?

The top of the box is meant to superficially looks like a clock face, close examination of the big black gear on the top will reveal a silver hour hand. The hands move in an undulating and irregular manner, however their relative rotational speeds are close to a real that of a real clock.

The gearbox has been doings its thing for about four years and over this time it has repeatedly been abused by airline baggage handlers. Despite this, it continues with only minimal repair work. In this video, the gearbox is running more than a little rough making a lot more noise than it should and its minimal operating speed is elevated.

Further constructional details can be found at the Meccano Model library: http://www.users.zetnet.co.uk/dms/meccano/dale/gearbox/index.html A fuller write up appeared in Constructor Quarterly #65: http://constructorquarterly.com/pmwiki.php?n=CQ.65

The answers to the questions are:

1/ 56
2/ The differential is a spur gear design unlike the more common bevel/contrate layout.
3/ The differential and the oscillating gear trio.
4/ Two of the pinions in the differential. The helical/chevron gears are all essential as their self centering nature is utilised.
5/ Worm gear.

Видео Meccano Gearbox канала paulidale