7.12: Transmissions Flashcards
What is to be noted about the initial lubricant?
Initial lubricant on a chain should not be removed
How would you remove a tight chain lightly?
Remove a tight chain light. Tap with a hammer lightly
What is the max allowable extension of a chain?
Max allowable extension of a chain is 2%
What is known as a Straight Lead?
Box unit in a Teleflex control run which is not suitable for heavily loaded controls is called a Straight lead
dried in hot air
'’Chain should be removed and checked for elongation - clean in paraffin, dry chain with hot air to ensure that all the paraffin is removed to prevent corrosion. Place chain on a flat surface & apply correct tension load’’
should not be removed
'’DON NOT REMOVE INITIAL LUBRICATION ON NEW CHAINS… LUBRICATE BY BRUSHING ON CORRECT LUBRICANT’’
it should be run over the finger through 180^ and checked for smoothness and kinks
How do you remove a tight link from a chain which is to be used on an aircraft control system?
(a) Dismantle, inspect, rectify and re-assemble the chain
(b) If the chain has a tight link, the chain has to be removed from service
(c) You may be able to remove the tight link by applying a light tap with a hammer
You may be able to remove the tight link by applying a light tap with a hammer
Removed and an elongation check carried out
Note: Elongation of more than 2% is unserviceable
it should be run over the finger through 180^ and checked for smoothness and kinks
2%
Straight lead
gears
Backlash = The distance or spacing between two meshing gears and the thickness of the engaging tooth
Typical Backlash 0.003 to 0.004 inch - 0.08 to 0.1mm (measured using DTI)
Option A: does not need proof loading
Option A: nuts and bolts
Option B: removed and an elongation check carried out
Option A: it should be run over the finger through 180^ and checked for smoothness and kinks
Option C: You may be able to remove the tight link by applying a light tap with a hammer
Option C: should not be removed
Option A: with the minimum of slack in the chain
Option A: gears
Option B: dried in hot air
Option B: 1/3
Option A: replace the chain
Option B: the pitch and width between the inner plates
Option A: pitch
Option C: M - (X * P) * 100 / X * P
Option C: 2%
Option C: a positive drive and axial movement
Option A: nuts and bolts
Option C: Straight lead
Option C: Lay flat on a table, apply tensile load and measure
1/ Mark it leaves on the mating gear
a) In the middle
a) lash and pattern
Note: Lash is another word for backlash
b) Middle
b) case hardened
c) even
c) at the centre of the tooth
1/ up to 1:600
2/ V blocks on a surface table
1/ place the chain under a load
2/ 2%
3/ a dial test indicator
1/ Running the chain over a hand/finger at 180 degrees
2/ The chain has extension pieces on it which prevent the chain been put on the wrong way around
a) Apply a load, measure chain and use 2% max formula to check extension
c) Oiled and coiled in greaseproof paper
B. replace the whole chain
b/ Bevel
