Questions tagged [machine-design]
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80
questions
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1answer
32 views
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 ...
0
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0answers
19 views
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'...
0
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2answers
34 views
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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2answers
42 views
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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1answer
35 views
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%...
2
votes
1answer
47 views
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 ...
3
votes
2answers
63 views
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 ...
0
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1answer
33 views
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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3answers
73 views
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 ...
0
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1answer
56 views
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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1answer
46 views
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 ...
0
votes
1answer
24 views
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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2answers
45 views
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.
1
vote
1answer
57 views
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 ...
0
votes
1answer
43 views
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 ...
2
votes
2answers
86 views
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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0answers
42 views
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 ...
3
votes
1answer
34 views
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 ...
0
votes
2answers
65 views
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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0answers
21 views
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 ...
11
votes
9answers
2k views
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 ...
0
votes
2answers
138 views
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 ...
0
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3answers
46 views
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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0answers
24 views
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; ...
1
vote
0answers
20 views
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 ...
1
vote
2answers
107 views
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:
...
1
vote
2answers
89 views
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. ...
10
votes
2answers
4k views
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, ...
1
vote
0answers
39 views
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 ...
2
votes
1answer
32 views
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 ...
0
votes
1answer
66 views
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 ...
1
vote
0answers
28 views
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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0answers
54 views
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 ...
0
votes
2answers
86 views
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.
0
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0answers
84 views
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 ...
0
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0answers
82 views
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 ...
0
votes
2answers
78 views
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 ...
1
vote
3answers
49 views
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 ...
1
vote
1answer
60 views
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
2
votes
1answer
209 views
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 ...
0
votes
2answers
52 views
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 ...
0
votes
1answer
25 views
How to find a reference line for " Form Tolerances"?
In my project I have to choose a form tolerances ( parallelism ) between the handle ( purple part ) and the part that sits inside it ( the grey part ), where the two parts slide on each other.
But I ...
1
vote
3answers
84 views
Mechanical Engineering: How To Amplify Kinetic Energy In Axial Rotational Gear Machinery? [closed]
When I originally posted this question 2021-04-08, I was inspired by pulley physics, especially after viewing these videos at this link and this link and this link. It is not necessary to go to these ...
0
votes
2answers
45 views
Gear configuration for a legged hexapod
I have an assignment for my Mobile Robotics course to design the drive mechanism for a legged hexapod and demonstrate its gait in motion.
The idea is to design the hexapod as per the following ...
0
votes
1answer
32 views
Shape of the shaft of knurling device
I'm trying to design and simulate a simple knurling device.
The shaft ( blue part ) has a flat surface at the other end, where the small grey pin connect the green body to the shaft. I guess you can ...
1
vote
1answer
53 views
Applying ISO fits to radial bearings
Do you need to take the bearing size tolerance into account when creating the tolerances for the mating hole/shaft when using ISO 286 tolerances?
For example, a 125 mm OD bearing with a desired H7 ...
1
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0answers
51 views
Design a Jig and Fixture for 3-axis CNC Milling Machine
Newbie Here!!!
This is my assignment task. I am required to design a Jig and Fixture for 3-axis CNC Milling Machine. The workpiece will be a simple aluminium block and it will be cut and shaped into a ...
0
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2answers
47 views
What is the name for a low pressure, low volume air reservoir?
I'm working on a project that requires very precise, but low pressure controls. I'm using a pump to charge a chamber to <15kPa, then a manifold of proportional valves to control output pressures ...
0
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0answers
37 views
how do i keep static deflection in a spring at a minimum upon applying gravity in a mass spring system without altering the response?
i modelled a simple mass spring damper system (with a vertical orientation) with base excitation in solidworks. After applying all necessary parameters, i plotted responses with and without gravity ...
0
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2answers
145 views
Where water goes in split air conditioner system in "dry" mode?
In split air conditioners, there are two tubes connecting the indoor unit and the outdoor unit. According to the generic schematics I find online (like this one), they are part of the closed circuit ...
