24

The vending machines have different product delivery box implementations. One of the most common ones -I've encountered- is the following: Basically you have a box which has an opening, as shown in the picture. The opening is big enough for the products to fall in. When the box pivots, then the closed section of the curved face "closes" the access ...


11

I think the locking mechanism is more or less like this: Note, the actual setup could be different but the concept of locking through a barrier that prevents the slide plate been pushed up remains the same.


6

Strictly speaking, very few metals are "stable" in terms of the laws of thermodynamics. True chemical stability is when the atoms are in their lowest energy state. For most metallic elements, various oxides, sulfides, and chlorides are lower energy states than the pure or alloyed metal. This is why corrosion occurs in the first place--the atoms ...


5

We define reactions uniquely depending on the reactants and products. Here are examples related to your question. Formation: Na(s) + (1/2)Cl$_2$(g) $\rightarrow$ NaCl(s) Lattice Formation: Na$^+$(g) + Cl$^-$(g) $\rightarrow$ NaCl(s) Solution: NaCl(s) $\rightarrow$ NaCl(aq) Hydration: Na$^+$(g) $\rightarrow$ Na$^+$(aq) Atomization: Na(s) $\rightarrow$ Na(g) A ...


3

When you are raising the plate you are also raising the bearings and since they need to roll there is the frictional component pulling down on the bearings and pulling down on the plate. When you lower the system you are pulling the bearings down and since they again need to roll there is the frictional component pulling up on the bearings and pulling up on ...


3

TL;DR (Serious): The problem is that you don't into account that the bending moment equation changes at different section of the beam. TL;DR: (Tongue in cheek) Don't do this unless you a) really really don't have anything better to do, or b) you are getting paid to do it, c) you really like this sort of problems. :-P (I wasn't getting paid to do it, so I ...


3

You advance the date manually, if required. It can be done without disturbing the time setting. Figure 1. Image source: Watches under 500. Position I – for hand-winding of the main spring. Position II – position of the crown in which you will able to change the day and date. If your watch only has a date window, you can change the date by turning the crown ...


2

This sketch is traced off from yours, you may update any missing/incorrect details. However, my impression is you were calculating the forces on plane a-a with the force applied as shown. For such a case, the bolt acts as a shear lug/pin and subjects to shear force only, no bending will occur or only with a negligible amount of moment resulted from the force ...


2

This is a type of ellipsograph or Trammel of Archimededs. It's a mechanism that is widely documented in textbooks for both the kinematics and the dynamics. Regarding the second part of your question, it really depends on two things: the position of the rod (angle) the velocity at the point of calculation. In the simple case of velocity equal to zero, then ...


2

$EI\dfrac {d^2_y}{dx^2} = M$ Procedures: Write equations for the moment in segment AB and BC as a function of x. Integrate the moment of each segment to get the slope, $EI\dfrac{dy}{dx} = EI\theta_x$ Integrate the slope of each segment to get the deflection, $EIy = EI\Delta_x$ Apply boundary conditions to set up equations for the constants. Solve the ...


2

It's a tricky one. Figure 1. Your isometric is missing this line. Figure 2. A clue. The six-cornered shape is flat so it must be a plane going through these three points. Can you draw it? Figure 3. The correct isometric view. Figure 4. Slide 25 by Shelly Wilke on SlideShare. This and slide 9 may be instructive.


2

you also need to take into account that the complete burn for octane is: $$2C_8H_{18} + 25\;O_2 \rightarrow 16\;CO_2 +18\;H_2O $$ Therefore $a$ should be equal to $\frac{25}{2}$.


2

It depends on the environment , relative to corrosion. Sea water is relatively corrosive to most metals, but again ,it depends. Splash zone is vey aggressive, low oxygen at great depth is relatively benign. What do you want the answer to be ?


2

The cylinder is cast iron which is relatively soft, so a softer material is used for the head gasket. The soft gasket deforms to seal against the head. Because of the very large size there are more likely machining imperfections that the soft gasket accommodates and seals. Whatever the reason , washers are unusual on engine head bolts. For very large flanges ...


1

Use a pulley with spooled string on it dropping a weight on the input shaft for input torque, and a pulley spooling up a string with a weight on the output shaft for load torque. With pulley radius and mass you can calculate input and output torques. You then need an RPM sensor on one of the shafts and you can use the gear ratio to calculate the RPM on the ...


1

you need to have your acrylic material properties data sheet, such as its modulus of elasticity, E and its max stress, $\sigma s$, and poisons ratio. Usually the acceptable deflection, y ranges between $y<L/180, \ or \ y<L/360$ Then you try different thicknesses, t, till you get the smallest t with acceptable deflection. Referring to Roark’s Formulas ...


1

You did pretty well, but @Transistor is correct that the horizontal line needs to be extended. Maybe it looks like this. However, I don't think the inclined plane is correct as there will be another line (shown in red) to connect the corners.


1

I am writing this as an answer to the comment about the superposition method. I started writing it in my original answer, but it was too long and confusing, so I opted to do another answer. Superposition method. Let's assume you have this problem. In that case you only need the following equation. Essentially what you do is you apply the above equation ...


1

I would suggest separate channels to each set of holes with orifice plates to limit the flow to / from each. That way you can control each set individually. The other solution will be to over-specify the flow rate so that the poorest one is sufficient...


1

It will be a next to impossible task to try and analytically predict the number/position/size of the holes in order to have exactly the same flow. Even if you do for a temperature and a set humidity, at different temperatures you might have unacceptable results. If you are really interested in equalising the flows, a better alternative is to use a flow ...


1

It depends on the loading conditions. It's important to note that the stress concentrations can be intuitively understood as created by the load's need to deviate from the hole. The larger the width of the hole, the more the load needs to move to go around it. If it's a uniform bi-axial load (your part is under tension/compression in both the X and Y ...


1

A screw thread would work, use the sensor to drive a motor with suitable gearing.


1

It is less economical to harness this energy/materials. From the perspective of the company, money is better spent on their immediate business needs such as locating large resources or improving the thermodynamic efficiency of their refinery. Reasons it may be less economical include: Intermittent flow; flow may be zero for long periods, with intermittent ...


1

I think this is a situation of "the devil is in the details', and of course, cost. In the US, gas from a few wells would not likely be of sufficient volume; but several/many wells could be combined (detail = pipeline plan and control). There are wells, mostly Middle East that do have enough flare gas. As a point of reference the last local power gas ...


1

What's acceptable will depend on your application. For a chair, 1mm of deflection will not be noticeable. For a CNC machine not so much. If you really care about optimizing the design, I would start by designing the object with narrow extrusions, and then see if/were the deflection will be too great, then bulk it up as necessary. This calculator ...


1

In general the acceptable deflection has to do with perception. What I mean by that is, if it is possible to perceive the deflection of the structure. Therefore it is usually presented in building codes (usually that's where you most see it), as a percentage of the span of the beam. However, there is no universally accepted allowable deflection. For example: ...


1

The short answer, is that there are bending stresses in the configuration you are presenting. The big difference is that for such small aspect ratio beams the shear stress are comparable to the bending stresses. Because, the Euler-Bernoulli beam theory (which is a cornerstone of structural engineering) ignores shear stresses, the equations are not applicable....


1

Assuming that the gear box is on the left end of the shaft (i.e. no flexible shaft between motor and gearbox). The angular velocity on the left end of the gear box is $\omega_1$. The angular velocity of the shaft side of the gear box is assumed as $\omega_1' = \frac{\omega_1}{N}$. The angular velocity on the right end of the shaft is $\omega_2$. So the ...


1

The SN diagram below answers your question. Note "High Cycle Fatigue (HCF)" failure is characterized by high repetitive cycles (N), usually equal to or greater than $10^4$, and low-stress (S) in the elastic zone.


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