Lets not forget the environmental impact of hydraulic brakes, production and disposal of brake fluid ect…
My prius has almost no brake wear, sometimes I pop it in neutral which bypasses the dynamic braking system and stop from highway speeds just so the rust can get scraped from the rotors.
Brake fluid and brake dust are an enemy to the environment, so maybe if cars had better dynamic braking systems and people would not race red light to red light like a bunch of amphetamine addled chimps, we could do away with brake pad replacements for the life of the car, and if we got to that point then it would make sense to do away with the maintenance intensive problematic hydraulic systems we have now. Think about it, lifetime brakes…
Using electricity to apply your brakes instead of hydraulic power seems, at least in my opinion, to fit the KISS principle. Using drum brakes instead disc brakes goes against the KISS principle, because drum brakes are a lot more complicated than discs. They take longer to service, and they take more skill to service than discs.
I totally agree on what you said about electric brakes. I just have a soft spot for drum brakes because they have many advantages over disc brakes, they also squeak less, last longer and have more stopping power in the equivalent sized package in comparison to disc brakes.
I think that if a car had electric drum brakes, and dynamic braking, The drum brakes would last the life of the car, no pulsation, no rusted pitted rotors, no squealing.
I thought the main problem with drum brakes is heat dissipation. I can well remember standing on the brake pedal of my '68 Valiant with both feet getting it to stop at the bottom of a short, but steep, hill.
If anyone can show me an electric brake system today (regardless of cost) that could be installed on a car and perform as needed, I’d like to see it. Otherwise, this is more of a ‘If ifs and buts were candy and nuts…’ kind of a discussion.
My Civic has discs in the front and drums in the rear, and on my car, the drums are louder than the discs. The electric brakes on my mother’s old camper trailer were pretty loud too.
texases, when I was a kid, not that long ago, most of today s tech, was only seen in sci fi novels and on the jetson s. I don t think your argument holds much water.
if we wanted to we could. heck, we put a man on the moon! the marvels of computer tech allow for the hitting of a speeding missile with another speeding missile.
stopping a car is like child s play in comparison. using electricity to clamp a caliper is not that hard to imagine is it?
Sure, anything’s possible. But if 100% electric brakes was anywhere near reality I’d expect experimental tests, use in racing cars, some example somewhere of somebody spending $10 million dollars just to get it working. Seeing none of that, I doubt both the need for it and the likelihood of it appearing within the near (say, next 10 years) future.
Take intake/exhaust valves - plenty of examples of alternate actuation methods (electrical, air, whatever) for a number of years, so I wouldn’t be surprised if something comes of that.
@WheresRick, in your occasional rants to get rid of old tech hydraulic brakes, you still haven’t made an argument against hydraulic brakes that makes any sense. Yeah, they hit limits on vehicles over 15,000 lbs. or so, but on 1-1/2 to 2 ton cars, hydraulic brakes work extremely well and are simple to maintain. Hard to ask for more there, and as a previous poster pointed out, disc brakes offer far more control during hard braking than do drums. Air brakes are needed on heavy trucks because they require more power than your leg can easily provide with workable leverage (I’m sure no one would want to deal with a foot of brake pedal travel), so they use another power source, an engine-powered air compressor. Also, it is a fairly practical way to hook up a tractor-trailer combo. No one would want to deal with air brakes on a car.
Rick, I have the luxury of having been driving cars well before disc brakes became common, and I can tell you from years of experience that disc brakes are much better. In addition to drum brakes’ difficulty dissipating heat and fading, and their tendency under certain conditions to lock up, they also completely lose their ability to stop the car when they get wet, like when driving through a puddle. The water stays in the drum, spinning against the inner surface, and dramatically reduces traction. They can be very difficult to dry out again. I recall many times having to “ride the brakes” until they dried out, which was a common practice in the old days.
Can you describe from a technical standpoint what “dynamic braking” is? That’s a new one on me. If there’s a system that doesn’t ultimately sacrifice pads, I’m unfamiliar with it.
Sure! I am no engineer or particularly smart or well spoken so I copied this from wikipedia…
Dynamic braking is the use of the electric traction motors of a vehicle as generators when slowing. It is termed rheostatic if the generated electrical power is dissipated as heat in brake grid resistors, and regenerative if the power is returned to the supply line. Dynamic braking lowers the wear of friction-based braking components, and additionally regeneration reduces energy consumption.
So basically in my Prius if I just lightly press on the brake pedal the hydraulic service brakes do not actually apply, the motor acts as a generator and that drag slows the car down. I believe that there has been a period of almost 2 weeks of strictly commuting back and forth to work that the cars braking was handled almost 100% by the dynamic braking action of the hybrid system, this seemed to cause rust to build up on the rotors a bit and I actually made several of the necessary stops on my way to work by popping the car into neutral which among other things, disables the dynamic braking.
FYI when you put a prius in Neutral everything is still mechanically connected, nothing actually disengages. The 2 motor/generators are just turned off electrically, and when that happens the car will not move, even if the gas engine is running.
Trains also use some form of dynamic braking, I assume the electrical energy just goes to resistors on trains, but I have no idea… I am sure someone here does, and it may have been mentioned in an earlier post
There are many forms of electronic brakes for vehicles, one is the electronically activated motor that powers a hydraulic brake system. There is even an on board battery that will power the brakes in the event of power loss of the vehicle. 17 pages, REALLY?
“I just have a soft spot for drum brakes because they have many advantages over disc brakes, they also squeak less”
With all due respect, don’t make me laugh. We have plenty of air brake trucks in our fleet. And they are, no question about it, much noisier when applying the brakes than vehicles equipped with hydraulic brakes. They squeak far more, near as I can tell
“no pulsation, no rusted pitted rotors, no squealing.”
I am often throwing drums on the brake lathe for pulsations
By the way, make up your mind one way or the other
By the way, make up your mind one way or the other
Electric or air
Please make a choice and stick to it
I like air brakes on larger vehicles, I also think it would be interesting to try them on a passenger car. If you are going down a mountain which would you rather blow? A hydraulic brake line or an air line? If you blow a hydraulic line good luck getting stopped on 50% of your brakes, if an air line blows you still have 100% of your braking, you just don’t get to decide when the brakes apply.
I like the idea of electric brakes, I think the options need to be explored. There are many options when it comes to braking. Electric drum brakes have been around for a long time, it would seem to me that it would make sense for a vehicle like the Nissan Leaf, or a plug in hybrid to have electric drum brakes.
Overall disc brakes are better, why can we not admit that drum brakes have advantages? The drum brake has been around for a long time and it has served us well.
Under braking, the traction motors become generators to power large resistance electric heaters. Same principle as a $50 electric heater from Home Depot.