10 votes
Accepted

How to fix this gear

Oddly enough, this problem can be fixed using a set of car keys and your wallet. Here are the steps to follow: 1) put the keys in the ignition of your car, start it, and drive to the motorcycle ...
10 votes
Accepted

How does a (pulley based) continuous variable transmission (CVT) work?

Review of geared transmissions In general, the idea of a geared transmission is depended on the gear ratio. The gear ratio $i$ affects many aspects of a gear transmission, and the following equations ...
  • 22.8k
5 votes

How can a clutch engage gradually without wearing away very quickly?

As suggested by the comments, there are a couple of missing factors in this animation. The first is there is no clutch being shown. A typical transmission involves a means of disengaging the power to ...
  • 6,417
4 votes
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Equal power transmission in 4x4 vehicles?

It depends on what type of differential it has. The nature of an open differential (as found on normal road cars) is that the spinning wheel(s) will get all of the torque. Proper off-road vehicles ...
  • 15.1k
4 votes
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Manual transmission: Why downshifting is less smooth than shifting up?

That's because when you upshift, you select a lower ratio, so your clutch speed drops. Since you took your foot of the gas, the engine rpm also dropped, and now the clutch and engine speed are close ...
  • 1,164
3 votes

Engaging and disengaging drive power

Tight or loose belts is one possibility, used on shaft drive to drills and lathes for years. Or consider the electromechanical clutch used on cars now to drive the ac compressors.
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3 votes

Friction clutch and the force required

Clutches do indeed carry quite lot of force but when you pull away from stationary the correct technique is to use fairly low revs and blend the clutch in quickly but smoothly. In this case the clutch ...
  • 15.1k
3 votes

How does my automatic car shift without complete temporary loss of acceleration

Multiple Clutches Many manual transmissions feature just a single clutch between the engine and the transmission. This requires that the clutch be disengaged before switching gears, during the switch,...
2 votes
Accepted

Why aren't detent clutches used in car transmissions?

Detent clutches use mechanical interference to force the halves of the clutch into hard engagement. The wear surfaces in this case are metal-on-metal which works well when the engagement duty cycle is ...
2 votes

How to accumulate torque of multiple independent gears?

There is a solution for this and it's called planetary gearset. All Toyota hybrids (at least the traditional not-PHEV ones) have a planetary gearset that sums together the power produced by motor-...
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2 votes
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Inertia and friction between gears

To turn your gear from rest, you'll need to overcome the inertia of your entire system (rod and gear). Torque = inertia x angular acceleration. You'll need to figure out what angular (rotational) ...
  • 2,337
2 votes

How can a clutch engage gradually without wearing away very quickly?

You missed an important part: The clutch Your intuition is exactly right that the gears would quickly shred themselves if that was the only thing bringing them into synchronization. But if you hadn'...
2 votes

Bandwidth vs Capacity

Your understanding is correct. Here is an alternate definition from Wikipedia - Bandwidth Bandwidth is the difference between the upper and lower frequencies in a continuous band of frequencies. ...
2 votes
Accepted

Why does the synchromesh in manual transmissions act on the output shaft?

Image from https://www.j-k-tuning.com/Transmission/BTrans2.php You can put them anywhere you want to (and people do). But it is easier to put them on big gears than little ones. If your four speed ...
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2 votes
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How does my automatic car shift without complete temporary loss of acceleration

I don't know why the other answers are talking about CVTs. Maybe I'm missing something? But the basic way how automatic gearboxes achieve smooth switches is that they use multiple clutches, instead of ...
  • 1,845
2 votes
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Small belt transmission: Radius difference?

I would estimate The radius to be a bit larger than 4 mm. How much, depends on the friction and stiffness of your belt. Similar to continuously variable transmission, CVT. If the belt is stiff enough ...
  • 21.2k
1 vote

Why does the synchromesh in manual transmissions act on the output shaft?

That is a simple animated drawing, getting a gearbox out of a recent car and stripping it would show you that most gearboxes rarely have dog clutches. They have synchromesh rings - usually a bronze ...
  • 14.2k
1 vote

Transmission line length with sag

There are to problems with the question. Over 250 kilometers earth has 5 kilometers curve. the weight and tension in the cable are prohibiting to normal materials. W*125000/60 = approximate tension. ...
  • 21.2k
1 vote

How can a clutch engage gradually without wearing away very quickly?

This just shows gears and synchromesh... no clutch operation at all. The clutch pressure plate moves some 5 millimetres or so but the pedal quite a bit more. The plate will slip until sufficient ...
  • 14.2k
1 vote

How does free space path loss change with receiver's antenna's height

Your equation is correct for your definition of $d$. However, your definition of $d$ seems incorrect. $d$ is supposed to the be distance between the transmitter and the receiver, that is the ...
1 vote
Accepted

How are water-tight transmissions made, like the kind you see on inboard boats, pumps or food blenders?

The seal you are looking for is commonly called an oil rotary seal ring. I found many brands and sizes with a quick search. the range of prices for a 1-inch shaft is around $5.
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1 vote

How don't dog clutches collide?

Usually because dog clutches are engaged when the shafts are stationary - lathes are a good example as they change speeds when the work is stationary and the tool dis-engaged.
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1 vote
Accepted

Electric engine and transmission

The essential question here is why or why not use a transmission in an electric car. Here are the underlying issues. It is commonly asserted that a DC electric motor is a constant-torque device, ...
1 vote
Accepted

Is it ok for clutch to slip in DCT in certain situations?

Clutches in car transmissions are designed on purpose to allow slip transiently, to make gear changes and standing starts smooth. This is not a bad thing. But they are not designed to slip all the ...
1 vote

Is it possible to design automatic transmission without torque converter?

The original automatics did not have torque converters ; they mostly had fluid couplings . Chrysler in particular , had more than a half dozen different ones in the various cars. They were more like "...
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1 vote
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Is it possible to design automatic transmission without torque converter?

That is not why torque converters are used in automatic transmissions. They are used because in addition to declutching the engine from the transmission at idle, they furnish torque multiplication, ...
1 vote

How does ferranti effect occur?

This is my point on Ferranti Effect. The Ferranti effect is a temporary voltage pulse (a “glitch”) caused by discharge of the energy stored in a magnetic field around a wire, OR it is a continuous ...
  • 44
1 vote

How does ferranti effect occur?

Electrical impedance and acoustic impedance take the same form mathematically, so I personally find it super helpful to think of electricity in terms of acoustics. Stand in an open field and shout. No ...
  • 3,535
1 vote

How does ferranti effect occur?

If you increased the frequency of the transmitted wave, eventually you would reach a frequency where the transmission line was resonating, with a node at one end and an antinode at the other. If you ...
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1 vote

How does ferranti effect occur?

Here is my take on the ferranti effect. Imagine a sea wall facing the ocean. Waves of height 1 meter are coming in toward shore and one of them strikes the wall. How high does the water splash ...

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