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23

Different gears have different drivers for having holes. One way you can categorize gears is by whether they are used primarily for transferring: motion: transferring angular position and angular velocity (see clockwork) torque: when the gears are used in power transmission Motion Gears that transfer motion don't need to transfer power. So their strength ...


8

In addition to the other answers such as weight reduction and inertia, there are other possibilities: Often there can be a precision machined hole for timing purposes. A common solution for some / many internal combustion engines to get camshafts timed to the crankshaft. Of course, dial gauges may also be used. Also, there can be threaded holes to help with ...


7

if you have them in line like the following picture then NO. The first and the last gear will have the same speed and the same torque (actually slightly less due to losses). if you wanted to retain a mechanical advantage you'd need 3 shafts and at least 4 gears like in the following image.


7

It could be for combination of reasons. lubrication: the holes will both pump and let the lubricant pass through. Reduced angular momentum reduces backlash and adds to gearbox responsiveness. Lighter gears need less shaft support, helping the averall compactness of the gearbox.


5

Depends on the application, but generally there are two reasons why: reduced weight lowers inertia loads (opposite of a flywheel), but more often less material = lower costs if these are high volume parts.


5

Also someone may have to pick the machine up and carry it. Reducing weight is not just related to the intrinsic function of the machine, its shafts and so on.


4

the tooth-root stresses in a gear are tensile and the teeth roots have sharp corners. This means if the glass gears were carrying any sort of load, the teeth would shear off right away. Furthermore, the teeth faces in a meshing gear set are in sliding contact, and if any grit gets into the space between the glass gear teeth, the faces will rapidly get scored ...


4

The linear force of the rack is equal to the tangential force on your pinion teeth (less power lost due to friction, typically 2-3% for spur tooth and racks). Tangential force = torque/(pitch diameter/2).


4

Screw: M6 M6 coarse has a 1 mm pitch. M6 fine has a 0.75 mm pitch. Unless otherwise stated assume coarse, so 1 mm pitch. Your motor is 1.8° per step. This is 360/1.8 = 200 steps/rev. The screw will advance 1 mm every 200 steps. As usual with Amazon, there are no datasheets and poor specifications in the ad which is what you linked to. There's a question in ...


4

Vibrations are the manifestation of things occurring at some frequency. This can be one per rev from imbalance (nothing is ever perfectly balanced) in gears spinning, one per tooth from each tooth changing where it presses against another tooth, one per specific tooth if a tooth exhibits an anomaly differentiating it from other teeth, specific interactions ...


3

Cost wasn't mentioned yet - Depending on the manufacturer, their processes, the cost of the raw metal, and the accountants it may be that the waste is swept up and reprocessed. For gears made of brass, bronze, aluminium or titanium this is well worth doing. Any other exotic metals depend on the cost per kilo. Copper and Lead would be excellent metals for ...


3

No. We can show this with math. The first gear pair has a ratio of 1:2, and the second pair has a ratio of 2:1. So, discounting losses, for every turn of the input shaft, the second shaft will make 1/2 of a turn. For the second pair, for every turn of the second shaft, the third shaft will turn twice. We can then multiply these together to see how many turns ...


3

A common solution to this which may or may not work for you is to use a centrifugal clutch. Off the shelf options would be too large for your application; and they wouldn't kick in until too high an rpm. But you may be able to 3D print something based on this principal. If you make the arms very heavy, with light springs it will work at lower rpms. You ...


3

That's only a good idea if the gears will be rotating very slowly with almost no load. Gear teeth undergo significant tension and compression loading, something glass is not good at handling. Would you ever make a hammer out of glass?


3

If I hadn't messed up understanding your idea then you can connect all rods to achieve the desired result. I've considered two bars connecting to maintain all rods paralel to each other. The starting position will be with Rod A and Rod B are inactive (position 0-0) and rod Y will remain in $Y_0$. The intermediary position Rod A or Rod B will be active, and ...


3

Your terminology is correct, but also sometimes called bevel gearboxes. A cheap off the shelf unit is a few hundred dollars. If that is too expensive you probably won't save any money designing and fabricating the gears and housing yourself. A u-joint is a cheaper alternative. But if you are intent on making your own, Boston Gear has good catalogue parts and ...


3

these things are sold cheaply (less than $20) for bending the output of an electric drill through 90 degrees, so you can drill holes in cramped places. they can handle from 1/4 to 1/3 horsepower typically. hardware stores sell them. they are called right angle drill drive attachments.


3

I think you've most criteria covered for the case you are considering in your post. The only criterion I haven't seen is wear and tear. Regarding wear and tear there are mainly the following considerations: the first is that the smaller gear should not have less than 11 teeth under any circumstances (preferably not less that 14 if possible). Usually 17 ...


2

As long as you're able to lock one of the planetary elements while the motor is powered that solves your problem but that doesn't seem like the most efficient solution. I would try an electromagnetic clutch between the motor and the pinion. When you have power, the clutch is engaged and the motor can turn the pinion. When you lose power, the clutch ...


2

A vertical force is either a axial, radial or combination of both depending on what part of it is aong the shaft and what is not. These describe all forces there can be on the simplified shaft system from bearings point of view. If you turn the axis of shaft running vertically then the weight just becomes a axial load if the axis is on angle then part of the ...


2

There are roller bearings that are designed to take vertical loads like that if the loads are large. Or there are thrust bearings, thrust washers or even taper roller bearings if the loads are not too large. Based on other information the bearing can be an interference fit on the shaft to locate it or the shaft can have a shoulder machined to locate one ...


2

Doesn't a boating cam cleat work in that fashion? Image source: Schaefer Marine. The harder the rope is pulled (to the left) the tighter the cleat bites it. If you can do the same with your friction pawl it too will lock onto the plunger even with wear over time. The other device that comes to mind is the Sprague or one-way clutch. Image source: SUMA ...


2

you can use a pantograph belt. They use them in large machines to transfer rotation to a moving drill to cut squares and what not. Basically they are several pullies assembled on a pantograph with links designed to move as prescribed.


2

Figure 1. Something like this? It will be faster as the drive pin moves through the lower section of the slot. Figure 2. This option should result in more even speed on the forward and reverse strokes.


2

The gears will have significantly lower friction forces compared to the pulley. However, the way I understand it, you are not really concerned about the actual friction forces developed. What you are more interested is the force feedback you will get with either system. The problem with gears and custom made stepper motors is the alignment of the gears. That ...


2

There a few steps in this problem. The first one is to figure out what is the torque that each shaft is subjected. The second one is to determine the twisting angle. In this you are making the assumption that the disks do not deform. So the regarding the torque (if you know the basics about gear assemblies this is obvious): the short rod (L/2) is ...


2

If the sprockets have the same number of teeth both the red and orange sprockets will remain in the same relative orientation. The writing on the orange will remain horizontal. If red has N teeth then the chain will advance N links per rotation. If orange has n teeth then it will rotate N/n teeth relative to the red. So rotating the beam one revolution ...


2

One cannot increase the diameter of a gear without changing at least one other aspect of the gear design. If the original gear design has characteristics to which you object, it's important to correct the design, rather than make possibly-incorrect assumptions about a solution. In this case, your suggested solution of increasing the gear size without ...


2

Theoretically, a well lubricated, aligned, and maintaned gear box should have theoretically zero static friction. If you are after estimating what the torque is to get it to move, to my experience, it is always easier and best to test the torque required to start it moving. The reason is that apart from the individual elements, how you implement and setup ...


2

The best I can think of is a barrel-cam indexer mechanism. Figure 1. Image source: nolte-nc-kurventechnik. See the Motion index drive on YouTube for a better view with fewer cam followers. The animation in Figure 1 shows a helical barrel cam but there are many other options. For industrial indexers there is often a period of "dwell" put into the ...


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