Questions tagged [motors]
The motors tag has no usage guidance.
267
questions
2
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3answers
48 views
Why is the Bush of a motor not replaced with a ball bearing?
Ball bearing reduces friction to a large extent than sliding friction. Motors use a metal ring called bush which slides against the shaft when the shaft is rotating. If a force is exerted on the shaft ...
-2
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0answers
14 views
Please explain the self-speed regulation of a DC shunt motor using formulas and equations of motor?
A wonderful explanation (by Brad) of speed regulation of a DC shunt motor is already given to a question raised by myself earlier. But I couldn't relate the stuff to the relevant equations. Not ...
0
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1answer
11 views
Isn't this explanation of speed regulation in a DC shunt motor wrong?
This site:(https://www.motioncontroltips.com/faq-what-are-dc-shunt-motors-and-where-are-they-used/ ) explains the speed regulation of DC shunt motor as follows: If the load on the motor is increased, ...
0
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0answers
14 views
Rotating vertical pole setup
software person here, venturing for the first time in the design of a mechanical system for a hobby project. Please note I have some experience in disassembling, fixing, reassembling mechanical ...
0
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1answer
26 views
Contrradicting answers for relation of speed of a motor with current
For a DC motor, speed of the armature is inversly proportional to current.
But at the same time, we know that torque of the armature is directly proportional to the armature current. Since speed can ...
0
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1answer
37 views
Calculating needed motor to spin a disk at low RPM
I'm designing a machine that I need to spin a horizontal disk at low RPM using a motor and gearbox. I'm not good at physics so I need help to find a motor/gearbox to fulfill my needs.
It's a ...
0
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2answers
39 views
oscillation motion from DC motor (computer fan)
I intend to make an oscillating motion from a simple computer DC fan (say 5V).
My question is: could a signal generator with a sinusoidal signal of (say voltage 5V and frequency of 5 Hz) be used to ...
0
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2answers
61 views
Why cannot series DC motors self regulate its speed?
When load increases on shunt DC motor, the speed decreases resulting in a downfall in back-EMF. This in turn, causes the net voltage, and hence the current to increase causing an increase in torque ...
0
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3answers
31 views
Does it matter the type of motor used ? Couldn't the wiring be changed to achieve high starting torque?
A series DC motor has a high starting torque thanks to its field wiring consisting of thicker wires and fewer turns resulting in high starting torque. And a shunt DC motor do not have a high starting ...
0
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1answer
28 views
Wouldn't placing an inductor instead of a capacitor have the same effect in fans?
A capacitor is kept in the circuit of a fan to overcome the trouble of having torques in both directions. I would like to know if the capacitor could be replaced with an inductor without resulting in ...
0
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1answer
25 views
Why doesn't the flow of current through the conductors in the rotor of a fan affect it?
The rotor of fan is shown as a series of circles arranged in a circular manner. From youtube videos, I came to know that this is sort of a top view and the circles actually represent conductors ...
0
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1answer
35 views
What is causing a pulsating, low-frequency vibration in an induction motor?
I have this old squirrel cage induction motor (nameplate below) that I just replaced the bearings on. When it runs, there is a rattling noise that gradually gets louder and then softer, repeating ...
0
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0answers
16 views
How To Obtain The Correct Differential Gears With Motor Shaft Adapters
My knowledge in gears in limited to their types (bevel, spur, etc). I am trying to combine the power/torque of two DC motors using a differential gear.
I have a good handle on the idea and design ...
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1answer
23 views
Atmospheric motor concept plausible?
So this is kind of like a stirling engine. Would this work?
A box that has a crankshaft, and two connecting rods that is under a vacuum (with no air inside of it.) The connecting rods are facing ...
0
votes
1answer
46 views
Get engine rpm using accelerometer
I'm studying the possibility to read an engine RPM by reading the vibrations of it. Basically an engine is "oscillating" on a car chassis on all 3 axes (X, Y, Z) but mostly on the Y one. When ignition ...
1
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0answers
22 views
DC motor Magnetic axis of armature winding vs EMF
When considering the cross section of a DC motor we have:
I notice that the Magnetic axis of the armature winding is aligned with direction of the EMF that will cause the rotation. Is there a ...
0
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2answers
53 views
I've never seen this type of flexible coupling, can someone tell me what it's called?
Putting together a project, I've found this clutch but I've never seen this type before. It has a sort of flexible plate connecting the two parts, attached to both in two places corresponding to where ...
0
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1answer
30 views
off-scale torque measured - what is my torque arm?
I have assembled a benchtop torque measurement stand for evaluating electric motor and controller efficiency.
The motor is 49kV , 5kW brushless outrunner.
Input power reading is taken from motor ...
0
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0answers
15 views
BLDC motor - stator
Can someone help me with this stator? I need to know the relevance of the bump up the side of the stator highlighted in yellow as well as slots. Is it to do with startup? Also can you clarify written ...
0
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0answers
18 views
Generally speaking are inrunner motors better generators than outrunner motors or vice versa?
Using a motor as a generator but looking to test something
I understand that outrunners have a higher torque but would that be neccesarily good for generating electricity or not?
0
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1answer
38 views
How effective are pancake motors as generators and why
Using a motor as a generator but looking to test something
Why would or would they not be good generators
thanks
0
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3answers
84 views
Cheap electrical motor that can spin freely in both directions when unpowered
I am looking for a cheap (preferably under 2000 USD) electrical motor that can spin freely in either direction when the motor is unpowered. The motor will be used as an alternative source of power to ...
0
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0answers
17 views
Hub Mount Motor to Flange Mount
I have spec'd out a pneumatic motor with acceptable torque for a tension application. The motor has a 1.25" hub with set-screw indent for it's mounting method.
Since this a prototype system, I don'...
0
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0answers
34 views
Starting of direct current Motor
what happens if starting arm of starter does not return to "OFF" position after a temporary supply failure?
-1
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2answers
66 views
Motor torque calculation, about the units
This link shows a motor torque, power, and speed relationship, as shown below:
With regards to its units, how does kW and RPM become equivalent to N.m?
0
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0answers
20 views
Borewell motor water outlet adjustment
Recently we put 500 feet borewell in our area, it's hot summer season now. Person who drilled the borewell told me that we can get 1.5 inch of water now. During winter season we can expect at least 2 ...
0
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1answer
29 views
Are stator magnets in brushed DC motors radially magnetised?
In an electric motor like this one, are the stator magnets radially magnetised, as in, each of the two magnets has opposite poles on the inside and outside diameter?
2
votes
3answers
71 views
How to connect a motor with a 4mm shaft to a propeller that takes 1/2 inch shaft?
I have a motor with a 4mm shaft. I've purchased a propeller that's designed to fit a 1/2 inch shaft. How can I securely couple the two?
0
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1answer
26 views
How to Wire a Brushless Motor with 8 stators?
I am currently for the past few years creating a Brushless Motor on and off. The stator I have built has 8 Stators and I cannot seem to find out how to wire this. I see most Brushless Motors with 9 ...
2
votes
0answers
35 views
Finding Supply/Nominal voltage for Torque Motor BLDC
I'm a bit confused by torque motors datasheets as it never mentions any nominal voltage. I would like to run a torque motor on a 24 V battery.
The required max torque is 150 Nm (=21000 ...
0
votes
1answer
46 views
How can I make a motor powered hammer swing more naturally than a Leonardo cam?
Most people are probably familiar with Leonardo hammer cams. But I'd like to make a motor-powered hammer that swings more like this (apologies for the crude diagram):
The hammer would fall due to ...
0
votes
1answer
49 views
What are the non-practical features of a sterling engine that cause the internal combustion engine to be used instead?
What are the non-practical features of a sterling engine that cause the internal combustion engine to be used instead (in a car)? (e.g. price, size, the power to weight ratio, etc.)
Can you name any ...
0
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0answers
20 views
PLEASE ANSWER Sterling vs Combustion Engine
This may be difficult to answer but, theoretically, if you had a car with a sterling engine that produces say approximately 300 horsepower how much of any specific heat source would need to be used if ...
0
votes
1answer
57 views
Is there a motor design where a rotor gradually moves into a stater?
I was wondering if there is a motor/generator design where the rotor moves gradually in and out of the stator along the axis of rotation, or the stator over the rotor. If so, I'd like some resource(s)...
0
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1answer
18 views
Which mounting bracket to use with a geared box?
Which 90 degree bracket would you use for this one? Do you have any suggestions for what i should be looking for, I find it very hard to find something. It is 5cm between all the outer holes.
Would ...
0
votes
1answer
47 views
Pump Characteristic Curve
I am bit confused about the curve:
We could observe from the [Pump curve] that Total Head decreases with increase in flow rate, but for [System Curve], it is opposite, i.e, Total Head increases with ...
0
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0answers
8 views
Looking for a clamping actuator or back-driveable DC motor
I am a university student attempting to build a haptic feedback glove, and while I do have a main design using electroadhesion, it is a bit finicky, thus I am looking for alternatives for design.
...
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0answers
26 views
Is it possible to mechanically switch between rotational directions of an output shaft?
I know that it would not be possible while the input is still rotating, but is it possible to create a gear box or chain assembly that can change the direction of rotation?
0
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1answer
40 views
how to find the motor specification
I need a motor for my project. My aim is to move a 10 kg mass using a belt pulley system, with a velocity of 15km/hr to a distance of 3.6m. The maximum time for moving the same is 1.5 sec.
Can ...
0
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0answers
27 views
What kind of electric motors are used to build industrial robot arms?
I'm fascinated by how robot arm nowadays can combine precision with operating speed (e.g. KIRA by Motorized Precision).
I can imagine building a robot arm with stepper motors would be pretty precise ...
0
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2answers
35 views
Would some manufacturing processes be more efficient if driven differentially by a single motor, up to ~150 kW, than multiple lower-rated motors?
I'm writing a discussion paper on the potential energy efficiency benefits of integrating different manufacturing processes by co-location on the same site. One possible field for integration is in ...
0
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1answer
34 views
How to adjust power requirements for a propeller working against a pressure head
I'm in the process of building a hovercraft. In order to lift it, I'll need a motor directing the flow of air into a skirt. The specs for the motor I'm looking at say that it can turn a 15x5 dual-...
2
votes
3answers
143 views
PID control of a DC motor with PWM from Raspberry Pi - how to cross dead area?
I'm driving a DC motor (actually a linear actuator) with a Polulu motor controller from a Raspberry Pi. The motor drives if you ask for anything between 20 and 100% duty cycle, so there is a dead zone ...
0
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1answer
78 views
The torque I need to lift the device and correct gear ratio for the device to be as fast as possible
The device have to climb a pipe vertically. I have a DC motor with power rating 21.2 w, output speed 13360 rpm and maximum output torque 154.4 gcm.
My device is 1 kg and I have wheel with 0.012 m ...
0
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2answers
90 views
Calculating proper specs of DC motor for rig driven on the rope
I'm trying to build a cablecam, a picture that serves only for illustration is:
The DC motor is
48V
5000W
6000rpm
6000 oz-in stall torque
85% effiencity
0.066 Ohms Resistance
135Kv (RPM / Volt)
...
0
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0answers
45 views
Need help picking motor to wind a spool
The application is a motor attached to a spool to wind/unwind window blinds.
I would like to operate the motor at $v=0.2\text{ m/s}$, with a max load of 1.5 kg.
I need to know the ideal diameter ...
0
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1answer
52 views
How can you calculate the torque and speed of a single output gear being driven by two different input gears?
I am building a gearbox that needs to lift around 50lbs very rapidly. I already have a single planetary gearbox that does the job in around 7-10 seconds, but I would like to cut this time down ...
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0answers
25 views
What motors to use to guide tape with high speed
My field isn't dealing with motors and such at all, however, I now need to build something that controls two motors.
So I have two guiding reels with tape between them, similar to old tape recorders. ...
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2answers
112 views
Is the speed of a DC motor proportional to PWM?
I'm trying to control the speed of DC motor but unsure of the relationship between speed and PWM. I'm aware that the bigger the duty cycle, the larger the speed, but how exactly would this ...
0
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0answers
23 views
Example induction motor
I have three phase induction motor:
$U=6\text{ kV}$
$P=630\text{ kW}$
$f_1=50\text{ Hz}$
speed of rotor $n=1410\text{ rpm}$
Maximum moment is reached when $n=1120\text{ rpm}$. Now voltage and ...
