Why don't they make a car without the clutch?

Question

without a clutch, but with manual shifting gears ? a car like that would be way easier to drive.

Answer 1

there are cars like that. its all in the gearbox. its called Semi-automatic transmission.

http://en.wikipedia.org/wiki/Semi-automatic_transmission

Answer 2

Learn to drive a stickshift. It's not hard.



However, there are already cars that have transmissions like you're referring to. BMW SMG, VW Golf GTI has one as well, and the Mitsubishi TC-SST, or Twin Clutch-Sport Shift Transmission in the new Lancer Evolution, as does the Nissan GT-R. Mind you, all these transmissions would cost a minimum of about $10,000 to replace if you break it, with the GT-R's going for about $35,000. Basically, they have 2 input shafts and 2 electronically controlled clutches. Gears 1-3-5 are on one shaft attached to one clutch, and gears 2-4-6 are on the other shaft attached to the other clutch. When you put it in first and give it gas, the computer engages the clutch and you drive away. When you tell it to shift into 2nd by moving the shifter or hitting the paddle to up-shift, the transmission is already in 2nd gear, but with the clutch dis-engaged. When you hit the paddle, it electronically, and immediately, engages the clutch for gear 2, and disengages the clutch for gear 1, then moves the next to gear 3 so when you up-shift again, it can do the same. This gives the transmission a shift time of about 40 milliseconds, or something like 1/10th the time of a standard automatic.



Edit:

Automatics and CVTs don't have clutches. So anyone who thinks so is a complete idiot and shouldn't be listened to.

Answer 3

On a manual transmission, as you put the car into gear, you first push the clutch so that the engine is no longer connected to one of the gears (the other gear is connected to the tires). When the two gears meet, the gears can quickly mesh together because one of the gears is connected to nothing.



If you do what is called "slam shifting" and force the car into gear without pressing the clutch, the gear is still connected to the engine, so for it to mesh with the other gear (the one connected to the tires), not only does the gear need to change rotation speed, but the engine does, too. This does not happen easily, and this puts a lot of wear on the gears.



An automatic transmission automatically engages the clutch and automatically shifts the gears. Some automatics can be manually controlled, so you tell the transmission which gear to go into, and the transmission still automatically handles the clutch. You are electronically telling the transmission to shift gears. You aren't physically moving the gears with a lever (the gear shift).



If you were to physically move the gears (a true manual), the transmission wouldn't know when to activate the clutch for you.



There are also cars that use a continuously variable gear, so the gear can change its gearing ratio without switching to a different gear, so no clutch is needed.



So, buy an automatic, or buy an auotmatic that can be manually controlled. It goes by different trade names. Porsche calls it Tiptronics.

Answer 4

I think they call these paddle shift automatics or tiptronic automatics. I have put thought into a liquid based clutch kinda like the way a torque converter works giving you the ability to hold more amout of torque to the transmission before letting off the brake. Plus I believe the torque curve for drifting a turbo or supercharged engine would be alot smoother and more manageable this way.

-Edit-

Frank is an idiot and doesnt know how automatic transmissions work. There is no clutch in an automatic. The gears are controlled by and electronically controlled hydraulic mechanism. your "slam shifting" theory is dumb. Older manual transmissions did not have the synchronizers that newer(post 1950s I believe) do now. So shifting on old transmission you would have to match the engine speed to the gear speed before letting off the clutch. you honestly don't need to use a clutch with newer transmissions if you can shift at the right points because the syncros will do all the work for you. Please educate yourself before giving LONG stupid misinformed post of pure crap.

Triple edit, just seen Frank's Facts on CVT transmissions.

CVT transmissions are what you would find in a 49cc scooter. scooters have clutches, but not the same kind of clutch you would think. also my dad's 2010 honda insight has a CVT with a clutch like disc on the flywheel

4th Edit

Yes it is possible but you would need an electronically assisted initial start up(from a stop at stop lights and reversing) I've been trying to devise a setup with a 1990s Miata with a 13-b rotary(less weight more power) also having 2 electronic engines on the front hubs that recharge a lithium ion battery when braking and help with uphill acceleration to conserve gas. Your question helped me realize that a clutch wouldn't be needed because it could start from a complete start with only the electric motors and allow you to shift into 1st at about 4-7mph. Although you wouldn't be able to go anywhere if your battery died or motors went out unless you started it in first and slammed the gas. Thanx for the help

Answer 5

When a car shifts gears there needs to be a brief rest in the pistons otherwise it will stall the purpose of the clutch in manual cars to allow the car to realize that brief rest. Without a clutch switching in a manual car we severely wear down on the cars engine and probably cause more trouble than its worth.

Answer 6

BMW's SMG transmission would be the closest thing you would find to a manual transmission with out needing a clutch, other wise an automatic with an auto stick just + and - gears

Answer 7

The cars must need a clutch otherwise they wouldn't make them like that.