14

Rotating shafts are subject to deflections, even without applied (transverse) loads. To reduce excessive shaft deflection: Avoid operating speeds near the critical shaft speed, where the shaft vibrates at its natural frequencies. Ensure the shaft is concentric, where its center of mass rotates about its geometric center. Assuming the shaft is concentric ...


10

A "1 ball bearing" does not mean the bearing has 1 ball. Or 2... It means that the motor / fan has been designed with one ball bearing assembly - which may contain 6, 8, 10 or 12 balls depending on the size and design. For example a caged bearing will have fewer balls to allow for the cage and this reduces inter-ball friction. Otherwise, the balls ...


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 ...


7

Typically jewel bearings (as you've described) are not used in large scale industrial equipment. The main reason jewel bearings are used is their inherent hardness. The bearing material has very little wear over the life of the bearing. Most of the wear occurs to the shaft riding in the bearing. In industry, you typically want to avoid wearing the shafting ...


6

Your initial assumption is a bit flawed. You can not just draw the conclusion that all friction is the same. It is like saying all birds i know of can fly thus all birds can fly. Which is obviously untrue. Moreover, continuing this similie, you also imply that there is only one kind of flight. In reality friction is a highly complicated phenomena that ...


6

The lubricant you put into the spinner bearings has both viscosity and surface tension, and it coats the rotating parts inside the bearing. Therefore, as the spinner bearing revolves, it churns the lube and makes and breaks air/lube interfaces- which dissipates energy and makes the spinner slow down. This energy dissipation mode is absent in the case of a ...


6

Your mechanism is going to lock up like the old car jacks immediately, due to differential raising of the platform. I am sorry but it looks like a textbook example of what not to do. in most real-life cases where the lifting actuator has to be off-center, they use a linked pair of scissors mechanism, like what they do in trucks' gate lifter, or the hydraulic ...


6

Does anyone know if this would be a good idea? The proposed design has poor rigidity towards torsional loads. It doesn't matter whether the actuator is off-center or if the load is off-center: if load's center of gravity and actuator are not at the same position, the torsional load will likely damage the bearings. In your example with two guide rails, ...


5

The number of balls in a bearing affects a couple of different properties of the bearing: Bearing Speed Bearing Strength Bearing Life Bearing Cost A Full Complement bearing means that the bearing has as many ball as can physically fit. Having the maximum number of balls means that there isn't enough space left for a cage. The cage keeps the balls from ...


5

If that is true, then would not be better off just to remove the whole setup and have the axis of rotation free from bearings ... Ball bearings change a system from sliding friction (as in a journal bearing) to rolling friction which is usually considerably less. Ball bearings prevent wear in one place as would occur with a horizontal rotating axis at the ...


5

These are called “wire rope dampers” or “wire rope isolaters”, and their purpose is to increase the time over which recoil energy is transferred into the mounting, thus reducing the peak force.


5

Regarding the name, I don't think that there is an official technical name, but then again I'm not a native speaker (nor can I speculate on the function of this shaft which in some cases might lend it a name). However, if you go to any workshop with a lathe you should be able to order one of those. The main thing that you need to determine (apart from ...


4

One difficulty here is that the masses involved are quite small so you need a very low friction bearing. Many industrial bearings are designed for high loads and speeds with quite close tolerances so in many cases they can be a little stiff under small forces even though this is small in the context of their intended application. In your case you might be ...


4

RPM = revolutions per minute. In the context of vibration monitoring, 1 x rpm means a vibration frequency that is the same as the rotation speed (one vibration oscillation per revolution of the rotor), 2 x rpm means a frequency 2 x the rpm (two oscillations per revolution), etc. Because of nonlinear effects in the mechanical system, vibrations can be ...


4

rolling element bearings produce less friction, last longer, can position a rotating shaft with greater accuracy, and do not require pressurized lubrication in order to carry large loads. sliding contact bearings are cheap, easy to install, and are adequate for light loads without pressure lubrication, and are fine for cost-sensitive applications.


4

Those thin flaps allow the bronze bearing inside to tilt about slightly and thereby come into alignment with the axis of the fan shaft, thereby minimizing noise and friction. If the bearing as a whole is out of lubricant, then the bronze bearing will stick and can't shift into alignment and the device will be noisy and may also have difficulty spinning up to ...


3

It's just a fancy rolling cycloidal drive (not that that being simple makes it any less cool). It really bothers me that all the available articles only compare it to harmonic drives when it only bears a passing resemblance to them. Probably because it's owned by Harmonic Drive LLC. The bearing races can be abstracted as wire ring races that have been bent ...


3

The crosshead bearing slides within a track and connects to the conrod and then to the crankshaft. In a vertically oriented engine the pressure on the bearing is always downwards, resulting in a depleted lubrication film on the lower contact surfaces of the bearing shell. To supply lubricant to the entire bearing, high pressure oil is injected into the ...


3

Without knowing additional details, my attempt at a catch-all answer: Summary: attempt to minimize wear. Millions of cycles is a lot for even low-load contact surfaces. Use components with high hardness and smooth materials. PTFE or UHMWPE backed by metal for full-contact bearings, and AISI 52100 or AISI 440C for ball bearings. There may be an issue with ...


3

Your shaft is a beam. You must have something like this: X========X======== Where the X's are bearings. Things you can do to improve the situation: Slower rate of rotation Use stiffer material for the shaft Use bearings that control the orientation of the shaft, not just it's location (e.g. don't use bearings embedded in a sphere) Increase the diameter ...


3

There are a few patents for trackball that uses simple wheels. You can check them. An older one, is Trackball mechanism US 4952919 A. It's bearing can be seen from this assembly drawing. As you can see it uses two wheels with friction padding that rotates with rotation of sphere that are used to discern x-y motion. Although I don't understand your ...


3

I think it is similar to what it is called by MIT Fundamentals: Flexural Rolling Bearing or Rolling Contact Flexure in section 10.14. As is often the case, a hybrid system can combine the best of both worlds. So it is with rolling contact flexural bearings. These bearings allow for compact rolling element joints to be designed. These joints can ...


3

if you look at a ball bearing in cross-section, you will see that the balls are assembled into the two races in such a way that the races have side walls against which the balls can press as they roll. this means that a thrust load on one race will be transmitted through the balls to the opposite race without tending to push the races apart and open up the ...


3

The maximum speed for a bearing recommended by the manufacturer can be due to one of two limiting factors, Thermal, or Mechanical. The thermal speed rating (often called "reference speed") is calculated using ISO 15312 standardised operating and cooling conditions, and as such, if you are able to provide improved cooling in your application, then, you will ...


3

Most 'Swivel Chairs' use simple thrust bearings, which consist of a low-friction layer (either ballbearings, or a flat disc of plastic), sandwiched between a lower disc attached to the swivel legs and an upper disc attached to the chair base. the shaft coming down out of the chair base goes through the sandwich and extends down to where the legs branch off, ...


3

To add to the list of criteria in other answers: Cooling. If a bearing supporting a rotor transmitting say 10MW of power dissipates only 0.01% of that power in friction, that is still 1kW of heat being generated in the bearing. Rolling element bearings are relatively easy to cool via the lubricating oil since there an unobstructed flow path between the ...


3

If you cool the workpiece and the reamer is at "normal" temperature then your final hole will be larger. So if you heat the workpiece and it cools down after reaming then the final hole will be smaller... You need to know the size of the bearing before purchasing the correct reamer. I fitted new valve guides into a cylinder head once - not having a press ...


3

Just prior to this point in the video you can see that the display has been inserted from the front and this portion will be added from the back and screwed in. All that is required is to ensure that there is enough space between the two parts for the bezel flange not to be nipped. Many plastics have a low coefficient of friction with steel or nickel plating....


3

Shafts and bearings usually use interference or transition fits - they shouldn't slide and for installation you should use force - some kind of press or clamping tool would be best, eventually if such tools are not available - few gentle hits with a hammer (you shouldn't hit the bearing directly to avoid damage, use something, for example piece of wood, to ...


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 ...


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