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Questions tagged [transmission]

65 questions
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1 answer

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

How does the (pulley based) CVT achieve the following? no requirement for a clutch fuel economy smooth gear transition
NMech
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How does my automatic car shift without complete temporary loss of acceleration

When my car shifts gears, the car's acceleration never goes to 0. I feel that there is constant torque to the wheels throughout the entire shift. How is this possible during a gear change? Transmission is Ford's 10R80
Ardalan G.
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2 answers

Friction clutch and the force required

I recently learned the basics of automotive clutches, more specifically friction clutches. Here is a simplified version of their operation explained to me (the car starts at rest): The engine and the transmission are connected via friction plates.…
S. Rotos
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How are water-tight transmissions made, like the kind you see on inboard boats, pumps or food blenders?

I want to replicate the kind of interface you see on inboard boats, pumps, or food blenders. Basically, I want put a motor in a sealed vessel, and have it turn a prop outside the vessel, in water. Is this usually done just with a layer of grease…
Alex
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Manual transmission: Why downshifting is less smooth than shifting up?

Today while driving I had to make a quick shift to a lower gear that was not as smooth as it should've been. I've been taught that while shifting to a lower gear you have to be more careful when releasing the clutch than while shifting a gear up.…
S. Rotos
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How does this transmission valve "hydraulic computer" work?

I just came across this: The claim is that it is a kind of analogue computer. But I don't see any moving parts. How does it work? EDIT: If someone could draw lines on the diagram to illustrate, that would be great.
spraff
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Bandwidth vs Capacity

Two questions on wireless transmission, packed into one. First: I am confused about the meaning of the term 'Bandwidth' in a wireless transmission environment. The two most common definitions I could find are: difference between the upper and lower…
user27435
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How can a clutch engage gradually without wearing away very quickly?

Here's an animation of a gearbox and clutch from Wikipedia. I learned to drive recently, and was surprised at how the clutch worked, engaging gradually as I moved the pedal by fractions of a millimetre. How is this possible? It looks like the gears…
spraff
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Negative transmit power in dBm

I am calculating the transmit power for $K$ single antenna IoT devices in an Indoor scenario. The receiver has 64 antennas. I am trying to minimize the transmit sum-power, i.e., $\sum_k p_k$, where $p_k$ is the transmit power of $k$-th IoT device.…
Chandan Pradhan
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Why do high speed boats have 2 speed transmission?

For example in this link you can see a 2 speed gearbox for a high speed boat http://www.coanracing.com/custom-block2/transmissions.html/xtreme-marine-transmission.html , what even is the purpose of having different speeds in a boat? In the link it…
Timothy Scherer
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How to change the direction of a chain-sprocket system

I’m looking for a way to change the direction (90 °) of a motion transmitted by a basic chain-sprocket system. Is there such a thing as a chain-driven equivalent to straight bevel gears? I’m planning on buying a piece of land and building an…
Ludovik B.
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Finding a gear supplier for a contra rotating boat propellor

I’m the new propulsion engineer in a solar boat team (something like this https://energyboatchallenge.com/en/home-english/, solar class). This year I have to design and build a contra rotating propellor. It will exist of an inboard electric motor…
cedric van sweeveldt
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Gear Oil HP 85w-140 vs HP-140

I have a 4 Stroke scooter 150cc (SYM JET-14). Manufacturer recommends 85w-140 gear oil. The price difference between 85w-140 and single grade 140 is tremendous. Given that in my country and during summer the average temperature is 36°C/97F and it…
m.nasim
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Where do I start with learning how to transfer data via RF

So I literally have no idea where to start but I know what I want to make. The goal is to somehow transmit 25mb/s of data across 15km with high penetration. Acceptable for reaching through trees and rocky areas in the mountains. I would like to…
Karekin_FPV
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Engaging and disengaging drive power

I'm looking for a solution to selectively engage and disengage a drive shaft with a number of output pulleys, one-at-a-time, like a clutch. Speed would be around 1000 RPM, and torque less than 20 inch-lbs (about 2 Nm). Clutching must happen when…
PProteus
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