A Different Kind of Disc Brake: 1949 Chrysler (2023)
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A Different Kind of Disc Brake: 1949 Chrysler (2023)
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Re: A Different Kind of Disc Brake: 1949 Chrysler (2023)
#2Looks more like a typical manual car clutch setup, but interesting anyhow. Definitely more complex than the modern equivalent. Would not want to work on these..
Re: A Different Kind of Disc Brake: 1949 Chrysler (2023)
#3[flagged]
Re: A Different Kind of Disc Brake: 1949 Chrysler (2023)
#4[flagged]
If you've got something to add to the conversation please share it and don't be cryptic!
Re: A Different Kind of Disc Brake: 1949 Chrysler (2023)
#5So initially I thought it was just a drum brake that applied the braking force on the face of the drum in stead of on the circumference. But it seems the key invention here is some camming system that automatically increased the braking force as speed increased. So this system supposedly did not require a brake booster as part of the hydraulics.
I wonder what prevented this camming innovation from being transferred to the more conventional drum brake of the time?
I'm not an engineer, but I do have some wrenching hours under my belt. I see a flaw in the design: The two halves of the drum are held together by machine screws/bolts. The braking pressure from the pads is applied directly to these screws. If they are not properly fastened, or if they are loosening over time, then braking force will be directly impacted. A failure could result in a total loss of braking ability. A conventional drum or disk brake is kind of fail safe in that regard: The mechanical pressure from the brake pads is not transferred through any fasteners. I see this design less resistant to poor maintenance practice. Maybe they somehow accounted for this and the article failed to mention it.
Re: A Different Kind of Disc Brake: 1949 Chrysler (2023)
#6Looks more like a typical manual car clutch setup, but interesting anyhow. Definitely more complex than the modern equivalent. Would not want to work on these..
Early brake discs were often maintenance nightmares. Discs built into the hub (so you need to disassemble wheel bearings to take the discs off) or even worse, Jaguar's inboard rear discs (reduced unsprung mass, but you needed to remove the driveshafts and they were buried in the middle of the car). Lots of premature optimization went on.
Re: A Different Kind of Disc Brake: 1949 Chrysler (2023)
#7So initially I thought it was just a drum brake that applied the braking force on the face of the drum in stead of on the circumference. But it seems the key invention here is some camming system that automatically increased the braking force as speed increased. So this system supposedly did not require a brake booster as part of the hydraulics. I wonder what prevented this camming innovation from being transferred t…
The mechanism reads a lot like an admittedly more sophisticated version of what existed in early mountainbiking as the "self energizing" Pedersen brake. More braking for less force, but terrible at dosing. I'd be surprised if this mechanism did not suffer from the same problems.
Re: A Different Kind of Disc Brake: 1949 Chrysler (2023)
#8I have these brakes on a vintage massey ferguson 178 tractor. the mechanism tends to push back up the pedal when pressed, and the stopping force is weak. there is a reason mf moved abandoned the design.
Re: A Different Kind of Disc Brake: 1949 Chrysler (2023)
#9The pads are very thin and i dont see how they could be made thicker, them being inside the mechanism. I am not sure they would last nearly as long as conventional pads.
Re: A Different Kind of Disc Brake: 1949 Chrysler (2023)
#10So initially I thought it was just a drum brake that applied the braking force on the face of the drum in stead of on the circumference. But it seems the key invention here is some camming system that automatically increased the braking force as speed increased. So this system supposedly did not require a brake booster as part of the hydraulics. I wonder what prevented this camming innovation from being transferred t…
The mechanism reads a lot like an admittedly more sophisticated version of what existed in early mountainbiking as the "self energizing" Pedersen brake. More braking for less force, but terrible at dosing. I'd be surprised if this mechanism did not suffer from the same problems.
Leading shoes on drum brakes were self-energizing like the old Pedersen mountain bike brakes. With a leading shoe the pivot point is after the braking surface, so the friction tends to push the shoe harder against the drum. Most drum brakes had one leading and one trailing shoe.
Some motorcycles even twin leading shoes on the front (maybe even four leading shoes with two sided drum brakes). These had issues with modulation like the Pederson brakes. You also had twin trailing shoes when backing up, so you had to squeeze the brakes extra hard then.