brake by jake

how does a jake brake work?

there is a big device on modern trucks that goes BHHHHHHHHHHHHHHHHHR!, very loudly. when they low down.

a jake brake takes the internal combustion diesel engine and turns it into an air compressor.

the reason you hear that BHHHHHHHHHHHHHHHHHR is that the engine is now compressing air and blowing it out the exhaust pipes, rather than igniting a diesel air mixture.

it was just a dream when they first came out in the early 60s.

braking down the long mountain hills with heavy tonnage and overheating breaks is a nightmare.

formerly, there were water sprays to cool the brakes.

the engine absorbs energy and keeps the truck from moving too fast.

that was a big big difference in safety and brake expense.

the gaming of slowing a truck, or anything down, is to take energy out, rather than applying it.

when you turn the engine into an air compressor, the engine is absorbing a lot of energy and the wheels and drive line have to supply it; that's what slows the truck down.

it's saved a lot of lives in 50 years.

accidents from runaway trucks on downhill grades are legion.

before the jake brake, truck brakes would get hot, and lose braking ability.

with the jake brake, if you use your head, you keep the jake brake on to keep your truck at one moderate speed.

you arent using your regular brakes at all, but you have them as a backup.

the name is derived from the jacobs company, that invented them.

it was patented in 1962 by clessy cummins.

they close the valves. normally, the internal combustion engine opens a valve that opens the intake valve for letting a fuel air mixtue into the cylinder when the piston is going down or at the bottom of the stroke. that valve then closes. the piston comes back up and compresses the fuel air mixture to ignite.

if you shut off the fuel, the source of energy, and only allow air into the cylinder, and then close the valves, you have an air compressor.

simple, but very profound.