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25

From the "Solo Traveler" patent: A more specific object of the present invention is to provide a lid having an opening formed therethrough to enable drinking, and having a recess formed in the lid adjacent the opening to accommodate the upper lip of one drinking from the cup This is also illustrated in the patent diagrams. I came across this interesting ...


22

Most bridges (and overpasses) are built to cross over something. With a few notable exceptions, most of these "somethings" are relatively long perpendicular to the desired crossing direction and fairly narrow parallel to it. Therefore a simple "two directional" bridge best meets the needs of the engineering problem. Engineers always try to solve a problem ...


18

Once the cylinder is released and starts to accelerate downward, the rotating flyweights should pivot upwards to a certain degree (as shown in the drawing) and should act as a drag on each of the motors' rotor shafts and thus a drag on the falling cylinder No, there is no reason for them to pivot upwards. The gravity pulls the flyweights with the same ...


13

See the .gif below! EDIT: You may need to enable visibility of these handles if they're not on by default - it depends on your default profile/settings.


11

In general, each tooth of an involute gear is made up of two curves: the involute curve and the root fillet. The involute curve is essential for gears to operate properly, and allows power to be smoothly transmitted from one gear to the other. The root fillet on the other hand is not involved directly with power transmission or the kinematics of the gears (i....


11

Sorry for not taking your "Thin Hollow Brick-Shaped Object" as an example - I felt a standard notched test specimen would illustrate the principle more clearly: It can be seen that adding external radii to the test sample has no effect on the stress. In this example, cutting even more material away from the corners would make no difference to the failure of ...


11

In itself putting paper inside a glass will make very little difference. Glass is a brittle material and tends to fail by shock and point loading. Its static tensile strength is actually pretty good. What will help is packing paper between the glasses as it will help prevent them coming into contact with each other and dampen vibration and impact forces. ...


10

The earliest CRT displays were in fact round. However, that was more due to manufacturing tradeoffs of making large glass envelopes with vacuum inside than a desire for the display area to be round. Rectangular makes more sense than round for a variety of reasons: It's what people want to look at. We use rectangular pieces of paper. Photographs are ...


8

Before I start, let me disclose that I don't know a lot about the details of infrastructure projects or your file format, but I think the general considerations are fairly universal. There are a number of considerations when providing your digital model to a contractor, and in my work I have decided to offer them my model in some situations, but not in ...


8

I use polypropylene glycol in my CO2 laser tube under florescent lights and have not had any problems. It also comes with the added benefits of freeze protection and corrosion protection. If you would still like to block out the light you can use black hdpe tubing for plumbing and helical wrap the tube with blue masking tape. You could also spray paint the ...


8

It's a combination of 1, 3, 4, the product development cycle, and the nature of the product. 1 - Damage in materials is a cumulative process, the product of hundreds or thousands of little events (e.g. the tightening and loosening of the belts) or one big event (a crash). So, the product has to be designed to always have a certain damage capacity ...


8

Filling inside the cup with paper is just to lock in the wrapping of the same paper around the glass. It also offers coverage and protection of the rim of the glass. Because of the integrated, all-around coverage the whole package remains intact in the box with no chance of clinking against each other and it renders strength to the box as well. It is even ...


7

Honey dippers work by using the viscosity of the liquid to raise a small amount of the liquid from a reservoir. Spoons work by trapping the small amount of liquid in a gravity well. Spoons therefore will work even when the liquid has low viscosity. The honey dipper method only works with appreciable amounts of liquid when that liquid has high viscosity. ...


7

Multi-way bridges are rare for river crossings for the reasons you describe; however, they are seen as a component of highway interchanges, usually when left entrances/exits are present or access ramps have been "braided" into an existing system interchange, or where a SPUI has been built over an existing divided highway. Viaducts over railroad tracks or ...


7

Below is simple table for designing snap-fit joints from Bayer Snap-Fit Joints for Plastics a Design Guide, please consult the pdf for more info. As I understand your joint is C cross section with 1st type. You should also check for spherical joint clearance should be y/2. y = (permissible) deflection (=undercut), E = (permissible) strain in the outer ...


7

When the timer reaches zero, the microwave tube is turned off. Depending on your house wiring, this large reduction in load may allow the line voltage to rise a bit. The fan, which continues to run for a few seconds in order to get rid of the built-up heat, speeds up a bit as well.


7

While it is an interesting idea, I don't think a "static treadmill" is going to give you results similar to walking. A PFTE(teflon) surface would be really low friction, but I think there are some bigger issues you may need to address first. Walking is essentially a repeated process of balancing, tipping, and re-balancing. The algorithms your brain uses to ...


7

Most soda cans in the US are on the order of 0.1 mm thick according to the sources I've seen. So 0.25 mm seems plausible to me, assuming that you made no errors in your calculations.


7

Flywheels are used in space, but not for storage of energy. They are used for attitude adjustment, as the spinning of a large mass has significant implications in an object which is free to move. Unlike on Earth, where a flywheel or gyro can be spun up against the force holding it in place (bolted to foundations), and change in spin speed will cause the ...


7

Mainly cost difference. And also, a fan is sufficient for the job. The problem being solved is thermal stratification. That's caused by a lack of vertical mixing; the warm air rises to the top, the cold air sinks. Normally, there's quite a bit of movement in the first two metres or so from the ground - thermal stratification starts when the ceiling gets to ...


7

It approximately means it is allowed or forbidden to have scratches at the place of round. When you are making cylinder surface you can to do it many different ways: milling, welding, soldering. In one case must be strong requriment for smoothness of surface (for example in bearings need to minimize friction). In other cases it is allowed to have scratches (...


6

Are you bound to the shape/configuration of part you constructed in your question? If not, a simple 3-way pneumatic solenoid valve would make this very simple and leak proof(relatively speaking). They are inexpensive too.(eBay) You would have an input and the valve will allow flow through one outlet and then energize the solenoid and you will get flow ...


6

In ancient times roundhouses were constructed and are still constructed in predominantly lesser developed countries. One issue with roundhouses is, once constructed they can't be extended laterally and retain the same shape. Rectangular buildings can be easily extended and most of the original structure can remain - knock down one wall and extend while the ...


6

In many cases, it's done for the sake of precision. As an example, an engine block is often sand cast. All mating surfaces in the casting master are made oversize, with the intention being that they will later be milled down to their final size. Since milling is orders of magnitude more precise than casting, this yields a more consistent result — ...


6

Gear ratios can be referred to as hunting and non-hunting ratios. In a non-hunting ratio, any one gear tooth will contact its corresponding gears' teeth in the same place every time. In a hunting ratio, the number of teeth in the gear set have no common factors between them. This way as the pitch diameters 'roll' over one another it takes a very long time ...


6

The short answer: Yes, a longer gun barrel improves accuracy. Theoretical accuracy of handguns and rifles is driven by rifling, barrel length, and bullet mass. Rifling: When the bullet travels through the barrel, the rifling (helical grooves in the barrel) forces the bullet to spin by converting some of its forward kinetic energy to angular momentum. ...


6

The main reason is economics. Who is going to pay for all the additional lines? The other part to this is, will the additional lines have enough passengers to make them profitable and sustainable? If the lines are on the Earth's surface how much land will they occupy and could the land be better used for something else? If the lines are underground, or ...


6

Keep drawing combinations. You forgot Østerås to Vestli, Østerås to Bergkrystallen, and every other combination of possible origin and destination. This breaks down in a hurry. By the time you split up all the trains to hit every destination, you end up with only a few trains a day going where you want to go. Since you don't want to travel then, you ...


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