33

I will expand on DKNguyen answer, because to my knowledge also the two reasons are: reduce contact/bearing stresses (having a significant effect on thin finishes live galvanisation) change the joint tightening characteristics (see joint diagram). reduce contact stresses on surfaces. The basic idea is that since contact stress is defined as: $$\sigma = \...


27

It is for spreading out the stress. But it is also for giving the bolt a bearing surface to turn on. The washer always goes on the side (nut or bolt) that is being turned. It prevents it from marring up the work surface and also changes the tightening characteristics. I don't know the specifics of that though but that's what I was told by a toolmaker. Always ...


16

Except for special applications, most washers are made of dead soft steel, which deforms under the compressive load imposed by a tightened bolt head. As the washer smooshes, it minimizes stress concentrations caused by bumps under the bolt head and surface flaws in the part the bolt is running through.


15

To visualize part of Nmech's answer: in the image, the washer actually greatly increases the contact area of the bolt head. The bolt head looks pretty big: But most of that is the shaft, which obviously does not spread out load on the material. So the actual contact area looks like this: Comparatively, the bolt head on the washer looks like this: That's a ...


8

It is a high pressure seal and bearing unit. The metal assembly to the right with the yellow parts is the drive coupling. After Sam’s comment and looking at that part again, there are 3 distinct metal parts - the middle one with the holes is aluminium, while the outer two are the outer races of the two bearings. Two bearings are often used due to either ...


6

Another important part of the answer is the symmetry of the stress pattern. The stress caused by a bolt head varies greatly between the points of the bolt head and the straight sides. As a result local stresses, which are what you really care about because those are what the materials have to withstand, can be much higher than the average stress. A washer's ...


6

The image shows what is often known as a zerk fitting, aka a grease fitting. The ball seals the passage from the outside to the internals which require grease. A grease gun with a properly sized connector will snap onto the zerk fitting. The gun is used to pump grease under pressure to the area described in the image as "no space, grinds," likely ...


5

The name Rolamite was given to the concept of a flexible metal strip wrapped around rollers, to form a linear bearing. Not pictured in your image, there would be an outer casing which fixes the ends of the strip and prevents the rollers from moving perpendicularly to the length of the strip. And, if one or more of the rollers are to be attached to anything ...


3

The impulse causes lateral acceleration of the rod and rotation of the rod. $$ P=m\frac{dv}{dt} \quad \text{for lateral acceleration}$$ $$ P=I\frac{d\omega}{dt} \quad \text{for rotational acceleration}$$ We calculate the net acceleration for each point along the length of the rod and after multiplying that by the density of the rod we get the forces' acting ...


2

Combined thrust bearing and shaft seal / stuffing box. Yes, it's really called that. The nipple on top is to inject lubricant which has dual function of preventing water ingress to engine compartment. The thrust unit forward loads cannot be transferred to drive shaft / engine without: damage or serious design compromise The thrust bearing transfers these ...


1

In the analysis you are referring to the authors are only concerned about the amplification of the excitation force (they are not concerned about the total force). I.e. they only care about the additional force that the excitation is causing on the supports. (keep in mind that the vibration would still occur even in a zero-g environment if you added a ...


1

You have to show two reference lines for tolerance measurements. One is the longitudinal axis of the linked parts. The other one is the line through the center of the pin as shown below. Does this answer your question?


1

You have to remember that you can control independently (or with a fixed gear ratio), the rotational velocity for each roll. So, in order to decrease the tension, what you do is you decrease the rolling speed progressively in the output zone. A very similar concept which is under the same restrictions, is the belt pulley system. Below it shows the tension ...


1

Kevin Reid answered the question, and I've accepted it-thanks, Kevin! This answer is to post a copy of relevant parts of the original article that had become rather blurry in my memory. I'll probably post other related info as I dig it up in order to catch the best selection of search keywords possible in case anyone else ever looks for sliding mechanical ...


1

Gimbals are the classic solution for this: https://en.wikipedia.org/wiki/Gimbal And if you don't need any roll, you can omit one of the gimbal rings, in which case a pan/tilt mechanism is sufficient (often sold for photography.) You might look for a gimballed gyroscope toy and start with that. (Flight quality gimbals are expensive.)


1

Perhaps a "turntable bearing" also called a "lazy susan" bearing. Something like this one: https://www.amazon.com/Square-Inch-Susan-Turntable-Bearing/dp/B00ZSQSWTM


1

Look for overrunning clutch or power transmission elements. You may find a lot of info in Ringspann site: Ringspann power transmission section Or here: Ringspann catalogue


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