Questions tagged [machine-design]
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Question about engine reaction torque from gas forces
in the figure below the reaction torque equation is given by Fg41.x trying to rock the ground plane about the O2 pivot due to gas forces . My question is if the piston with the cylinder whole assembly ...
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Failure criteria for CFRP single plate bolted joint
Which equation can be used to find failure based on ply orientation.
Tension,shear & bearing faliure to validate against fem analysis
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Tension Arms In Watt Governors
I wonder why there is no tension acting at the arm connecting the flyball with the sleeve in Watt governors but it is only acting towards point P which is a pivot. Furthermore, the tension would act ...
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Is it essential for two meshing gears to have even number of teeth?
Should the teeth of meshing gears be even rather than odd numbers? If not, which is better?
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Modulating Output of a Pulley with Variable Inputs
I am working on a recreational project to take variable inputs and convert them to a constant output without substantially altering the force required to achieve such a task. The best way to visualize ...
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Force from screw on the clamp
I want to find out the force the screw (M5 , 12mm long) exerts on the clamp so it can hold the cylinder as shown in the image. I want to know whether the clamp can displace enough to hold the cylider ...
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Best type of pin to use when two parts are rotating relative to each other?
[Edit 1]: Added material of components.
I have a flywheel with a shaft connected to it. The shaft rotates with the flywheel, but also rotates relative to it, to give me a kind of camshaft motion if ...
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33
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Frictional wheels without slipping (gear system)
In the figure below it is stated that the friction force should always be greater than the tangential force in order to prevent slipping between two frictional wheels. My question is that if we apply ...
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Moving a Bushing in Circular Motion
I am trying to design some way of making a bushing move in a circle. Specifically, I want the center of the bushing to draw out a trajectory that is a 3" diameter circle. I do not want the ...
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derive functions for generating projections for the interpenetration of two cylinders for making fittings
I want to make custom fittings for constructing large molecular models using copper tubing.
I will need to cut a hole in one piece of tubing that will closely fit around another inserted piece. I ...
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Material selection for plunger to be compatible with pressure seal
I am designing a jig to insert a pressure seal into a cap.
The jig has a cavity which the cap fits into and then is loaded with the pressure seal which needs to be inserted further using a plunger. I'...
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Question about cam follower design
It's always said that jerk function should be smooth to avoid undesired vibrations. What exactly is the vibration in a cam follower mechanism and why is it important to avoid it?
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Is Smith Diagram and Modified Goodman Diagram the same? And how does one construct it?
I am confused about the names. Moreover, I haven't found any textbook which attempts to show step-by-step construction of these diagrams.
I would be happy if anyone pointed to some textbooks or even ...
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Unable to understand minimum length of engagement for bolts
I've attached a snap of the part I'm unable to understand Machinery's Handbook 29th Edition.
Here's a link to the ebook as well https://www.vtc1.org/cms/lib/PA03000913/Centricity/Domain/21/Machinerys%...
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designing a drill jig for manufacturing a finished product
what will be suitable drill jig for the given product? since the drill is not straight. so i'm not sure for the suitable design, kindly looking for kind help. thanks in advance!
if it would have ...
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Why do pneumatic valves need both a Safety Relay and an Air Dump to be safe?
If air dumps safely release pneumatic pressure from an industrial machine when an E-Stop is pressed, why is it also standard practice to cut electrical control power from the valves with a safety ...
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How to design a fridge / freezer / air conditioner / heat pump?
I have this question / problem in my mind for an estimated of ~20 years. Obviously, my life does not depend on the solution, but the quality of the life of my brain might get improved :)
Shortly: How ...
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Why actuators are mounted in inverted position?
Hope you are doing good.
Can anyone please explain to me why actuators are mounted in inverted position on some excavators?
Please see the image for better understanding of my question.
Another ...
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Question about theory of machines (kinematic diagrams)
Can I draw this part of kinematic diagram in this way, knowing that bolded W is a point of interest. so is my drawing true also? (my lines are in red and black(not bolded black))?
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Machine Design, finding the diameter of a shaft
L = 10 in,
$T_{max}$ = 153 in-lb,
$T_{min}$ = 13 in-lb,
Carbon Steel 1020 CR,
$f_y$ = 57 ksi,
$f_{ut}$ = 68 ksi
I am not sure how to solve if I do not have the weight of the shaft. I really appreciate ...
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Does F_x generates "Transverse Shear Stress" shear stress at the fixed end A?
Considering the applied forces $F_y=F_y=0$ and $F_x=400$ lbf, what type of stresses does $F_x$ produce? I understand that $F_x$ causes tensile and bending stress but not sure about the transverse ...
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Calculation of torque at the base
Hope you all are doing good.
Can anyone please guide me on how to calculate the different torques at the base as shown in the image?
Thank you for your time and help.
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What should be the thickness of machine tool bed?
I am developing Five-in-One machine tool which I did as a project working during 1984-85 in our Polytechnic college. Even though we made prototype at that time, now I want to make prototype for ...
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Motor For powered adult swing
I'm trying to design a powered swing for adults (similar to a baby swing, but scaled up). Am I right in assuming that this is functionally a pendulum and the power required is (0.5)mgsin(t)? How ...
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Designing a progressive die to make a blank on a thick steel sheet
Suggest and Design a progressive die to make a blank with a 2 mm thick steel sheet as shown in Fig. The ultimate shear strength of the material is 480 MPa. Calculate press capacity assuming 75% ...
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Direct way to measure perpendicular movement?
I'm planning a CNC machine build which will use many linear slides with bearing blocks moving on them. Some of these need to be in parallel with each other and others perpendicular to each other.
It ...
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What is a shaft collar called that is used to restrain a pulley?
I would like to look for a shaft collar like the one used in this photo of a cable robot:
As you can see, there is a flexure that clamps the collar onto the shaft (as a shaft collar does). In ...
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Can stainless steel be used in continuous high temperature environment (500°C to 850°C)
Can i use stainless steel as a furnace roof. Furnace temperature will be max upto 850°C. If so which ss grade will be the best in this situation. Thanks
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gear compatibility specification
I want to build a epicyclic gear system with planetary gears on flat carrier plate and outer ring as internally toothed (geared) slewing bearing. I want to buy a single row slewing bearing of 8 inch ...
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Aluminum weight saving
"Aluminum saves weight! Its 3 times lighter than steel!"
Also its 3 times weaker and 3 times softer. When comparing stiffness and strenght to weight ratio, aluminum isnt any better than ...
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Reaction forces on a three support continuous beam with two of them requiring compatibility equations. Superposition method done wrong!
I need to analyze a continuous beam of length L and three supports: A (at x=0), B (at x=L/2), and C (at x=L). An applied load P is applied at x=3L/4. Now, at A, the continuous beam is bolted to a ...
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Can tubes for fits & tolerance be purchased or only manufactured?
I'm currently designing a steel structure for a gym machine. I want to assemble two rectangular tubes, one being able to slide inside the other, for height adjusting. I intend to use a spring ball pop ...
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Reference design for a HSK machine spindle?
Is there a reference design somewhere on the web for a HSK milling machine spindle (mainly HSK type A, between 40-63)? I'm mainly looking at the fixating mechanism (drawbar et al) and its tolerances; ...
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Sign convention for angular velocities in 3D gear train
Consider a Humpage gear train shown above. We are viewing the gear train from right and gear B is rotating in clockwise direction. If we consider clockwise direction as positive what will be the sign ...
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Velocity or Speed Ratios in Gears and Gear Trains
I have seen the different definitions of the velocity ratio for Gears and Gear trains. I have referred a book called Theory of machines by S. S. Ratan. In that book the definitions are as following:
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In an open belt drive, which angle of wrap should be taken for calculating tension in the belt?
An open belt drive with flat belt has different angle of wrap on the larger and smaller pulley. I have to calculate a tension in the pulley. We generally use the formulae
Here θ is the angle of wrap. ...
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How do vending machines prevent people from stealing goods?
I never understood mechanically how a vending machine prevents people from accessing goods through the dispensing panel. From what I understand it's not a locked door that unlocks only upon payment, ...
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Can a semi-conductor cooler be powerful enough for a room? [duplicate]
I see semiconductors used for small fridges. I cannot find one large enough to cool a room (in place of a conventional Freon based, window air-conditioner). What engineering problems might a up scaled ...
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How is the assumption that stress and strain are elastic everywhere is valid for STRESS-LIFE method for fatigue life calculation?
Stress life method is generally employed for high-cycle fatigue (HCF) applications. while HCF region is approximated by $\sigma=a(N)^b$ which gives a linear graph on log-log scale, for steels it ...
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What type of electrical machine component for counting time?
I am looking for the proper piece of hardware to do what I'm looking for on my current prototype machine build.
I want a timer to begin counting upwards in seconds when a switch is activated, and ...
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How to determine minimum aluminum t-slot profile type for frame?
For a frame with dimensions 1000x1000x400, I am determining which T-slot extrusion type will be strong enough.
I am considering both 30-6060 (30 series I-type, metric) and 20-4040 (20 series I-type, ...
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Is it possible to narrow down a portion of shaft to its 1/5 of its diameter?
I designed this shaft for my center gripper. However the slot requires to be very deep, as you can see. I want to know if it's possible to produce
this part.
The main diameter is 30 mm and the small ...
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How do I read this schematic drawing notation for a drill hole?
It's for an NX part. I can't figure out the depths and such. I just know the placement of the 4 holes and that the diameters are 10 mm each.
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Number of Kinematic Pairs
Kinematic pairs are the connection between 2 links that can have relative motion between them.
But In six bar chain as shown below:
There are five pairs for them to be a kinematic chain. But if I ...
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Machine Analysis Problem: Finding the vertical force at joint K
Help me in determining the right solution in this problem. I already have an initial solution here but when I compute, my answer does not match to the answer key. I would like to know where did I ...
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How to measure a dovetail slot and it's mating component?
I have had some trouble determining the best way to measure a dovetail slot and it's mating component. The parts have some difficulty mating occasionally, and our QC department is having trouble ...
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static friction of gear pair
Im working on a project that has gearing system integrated. From my simulation results im dealing with a relatively small amount of input force at the gearbox and would like to know if the force would ...
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Sleeve and cotter joint
What does 0.1D signify in this cotter joint. I meant is it denotes spacing between pin and hole. I am new to machine drawing , kindly let me know. Thanks in advance
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Relation between links and pairs in Kinematic chain
I came across a equation for kinematic chain (for lower pairs only) :
L = 2P-4
where L: Number of Links;
P is the number of pairs
how could this equation be derived ?
EDIT: I tried putting values in ...
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3D linkage design - terminology
I am designing an animatronic head, which has five degrees of freedom: pitch, roll and yaw for the head part, and pitch and yaw for the neck part. However, the yaw movements for the head and neck are ...
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