Thread: Compressed air handbrake

I think that they work with spring actuated shoes on drums, the compressed air is used to hold off against the springs. Removal of air pressure releases the springs to activate the brakes. No air pressure, you don't move. I think is is standard on bigger trucks.

http://www.truckt.com Air Brake Chambers Explained



You would need to use one of the above explained brake air chambers. It is just a diaphragm much like the brake servo on your master cylinder.

My Mk3 Inter is fitted with a air operated spring brake. The diaphragm chamber is fitted to the shaft of the original brake.

A word of warning, there is a significant spring tension inside the chamber and people have been killed taking them apart with the wrong technique.

the easiest way Ive been able to think up for putting a spring on air off park brake onto a landy is fit up an x-Eng brake then put a maxi cylinder onto that

I've been giving it some serious thought for SWMBO's disco as her park brake is nearly shot.

Of course, any change such as this to a braking system woould require engineering approval. I find it difficult to see it being worthwhile - on the trucks you give as an example, it is a "side effect" of the spring on/air off braking system rather than being a design intention to give a quick acting parking brake. (the advantage of the spring on braking is that each wheel brake is fail safe and completely independent.)

John

Originally Posted by DefenderJim

Recently I have had the joy of driving a 4x4 Isuzu truck off-road. I had never thought about it before this but I found that the compressed air hand-brake was really useful when it came to moving off easily in different situations with the weight because it was either off or on with very short travel, also seems to be easier on the clutch.

Now forgive me for not understanding completely how this style of braking system works, but would I be able to/what would be involved in adapting this style of handbrake into my Defender? Or is there another option that would have the same benefits?

Cheers
Jim

I cant see it working off your diff lock compressor.
Any malfunction and you loose all your air, bang, the brake is locked on.
Major job to undo it all.
Spend the money on rebuilding the factory one or I believe there is a disk
handbrake conversion.

Didiman

It is actually quiet simple to release a Maxi-brake system, between the service brake canister and the Maxi brake canister there is a T-headed bolt with a 19mm (3/4") nut & washer holding it in a tube. Remove this bolt, insert it in the hole in the end of the maxi, engage the T head by rotating until locked, then tighten the nut till the brakes release, wind it all the way if you intend removing the clamp that holds the canister together, Regards Frank.

Originally Posted by JDNSW

Of course, any change such as this to a braking system woould require engineering approval. I find it difficult to see it being worthwhile - on the trucks you give as an example, it is a "side effect" of the spring on/air off braking system rather than being a design intention to give a quick acting parking brake. (the advantage of the spring on braking is that each wheel brake is fail safe and completely independent.)

John

I've already looked into it for the purpose of being able to control air braked trailers for recovery and yard shunting (not specifically for landrover application)

so long as your air system meets the requirements for air brakes in trucks it shouldn't be too hard to implement and get it engineered.

Spring on Hydraulic off? Possibly tapping a pressure line off the power steer pump, through a solenoid? Similar to the air over spring design, downside is, engine has to be running to release I spose.

What do alot of new cars have, where the park brake is just a button on the dash??? Electric Park brake?