|
|
|
![]() |
|
|||||||
|
||||||||
![]() |
| Thread Tools | Rate Thread | Display Modes |
|
#16
|
|||||
|
|||||
|
Re: CIM Voltage and Motor Suggestions
Quote:
I know the NBD won't work for you, I was just referring you to that so you could get an idea of the innards of one of these lovely trannies. If you're going with all Dewalt stuff, the only machining necessary would be to attach something to the spindle. I'm unsure of the thread on the spindle, but the easiest option would be threading the center of a sprocket with that thread. Then you just screw the sprocket on and put on a washer and put in the left hand screw. Look at the end of the whitepaper to see how it works on those. It should work similarly for this spindle. |
|
#17
|
|||
|
|||
|
Re: CIM Voltage and Motor Suggestions
There is no easy way to mount 4 CIMS with our gearboxes. Doing so would require redoing the gearboxes completely, so I am searching for perhaps something better.
Edit: Kevin, sorry for my lack of knowledge in this subject, but the only machining required would be to attach something to the output of the gearbox, right? I know on regular drills you unscrew the cap, place a drill bit or something inside, then screw it tight. I'm guessing that strategy wouldn't work for us though, right? Last edited by jakep : 11-08-2006 at 14:04. |
|
#18
|
|||
|
|||
|
Re: CIM Voltage and Motor Suggestions
The CIM motors are sealed units, meaning that the motor can has no venting and the armature (assumingly) has no fan on it like you might find on a Fisher Price motor. This means that all the heat generated by the motor has to migrate out through the motor can, either by radiation or through the bearings.
Neither is efficient or fast, and I suspect that the heat generated is going to fry the armature long before cooling the can with heat sinks and fans will do you any good. The CIM motors get pretty toasty as it is at 12 volts. As was stated, at double the power output, the motor will need to dissipate 1200 watts. To put that in perspective, an electric space heater I own has a maximum of 1500 watts. You might consider removing the end cap and drilling out some holes in it. Then place a muffin fan behind the motor blowing into the now perforated end cap. The added airflow might help keep the motor cool while running. It will certainly help speed up cooling it in between run times. Just how much of an improvement is might make is difficult to say, but some air flow is better then none. Modifying motor parts, especially removing metal, can be a bit hazardous to the motor's health, and I wouldn't recommend that you try it unless you are confident you can do so with out risking damage to the motor. |
|
#19
|
|||||
|
|||||
|
Re: CIM Voltage and Motor Suggestions
With some further info from jakep, this isn't necessarily a continuous use application. Atleast, it won't be operating at max power for more than a few seconds. It would hit peak power and past for a bit and then level off and operate somewhere below that. So it might not destroy itself too quickly. Perforating both endcaps and using a muffin fan might be enough to handle the extra heat. Certainly it's a cheaper easier option than the re-engineering and building that'd be necessary to use those dewalts. Though the dewalts would work exceptionally at this and I'd be highly amused to see a pair of hammerdrills in this application.
|
|
#20
|
|||
|
|||
|
Re: CIM Voltage and Motor Suggestions
Hmmm... See the problem is that if we upgraded the voltage we were using with the CIMs, we would have to re engineer our gearboxes with a different gear ratio so that extra speed would translate into more torque. Since we need to redo the gearboxes either way, those Dewalt ones are looking awfully nice
![]() The one problem at this point seems to be attaching the output shaft on those to our wheel, which has a key slot-thing already cut inside. Any ideas? I can get some dimensions for you guys if that would help. |
|
#21
|
|||||
|
|||||
|
Re: CIM Voltage and Motor Suggestions
Very interesting discussion so far...
I would like to add that the output power of a motor is not only a function of input current but also of the available field in the magnet structure. At some point, the magnetic field developed by the electrical structure may exceed the permanent magnets. At this point, no additional speed or power will be available and all excess electrical input is turned to heat. Without some testing at these extremes, we can not determine a point at which this will occur. Please remember that the resistance of the motor windings and brushes are also affected by heat which will change performance. Unfortunately, as nice as this motor is for a two minute match, it is not designed for anything approaching continuos duty, included are heat dissipation, brush life and bearings. |
|
#22
|
|||
|
|||
|
Re: CIM Voltage and Motor Suggestions
'Unfortunately, as nice as this motor is for a two minute match, it is not designed for anything approaching continuos duty, included are heat dissipation, brush life and bearings."
Which motor are you talking about, the CIM or the recommended Dewalt? |
|
#23
|
|||||
|
|||||
|
Re: CIM Voltage and Motor Suggestions
Quote:
|
|
#24
|
|||
|
|||
|
Re: CIM Voltage and Motor Suggestions
Hey Kevin, or other mechanically inclined person,
Could we use one of these (referenced fromt he NBD whitepaper) as a motor mount with the 24V Hammerdrill motors? http://www.chiefdelphi.com/media/img...e988043e_l.jpg |
|
#25
|
|||
|
|||
|
Re: CIM Voltage and Motor Suggestions
Quote:
Using a stock drill chuck probably wouldn't work because you couldn't get it tight enough. It would slip. To adapt a drill motor to a robot, you could take off the chuck by removing the left hand screw you'll whole chuck will unscrew from the gearbox output shaft. You'll be left with a threaded shaft. On the lower voltage XRPs, it is 1/2-20. I'm not sure if it is the same on the 24V model. So then, you just use a tap (preferably set up in a lathe or a mill) to put internal threads in the bore of your sprocket/gear/flex coupling/etc so you can screw it on the gearbox output shaft. Then you put the left handed screw back in the gearbox output shaft with a nice thick washer and that keeps the sprocket/gear/etc from unscrewing itself. It is all explained in the NBD whitepaper. Last edited by sanddrag : 14-08-2006 at 16:36. |
|
#26
|
|||
|
|||
|
Re: CIM Voltage and Motor Suggestions
sanddrag, I was talking about the 24V hammerdrill motors that Kevin Sevcik was suggesting. We would be buying the Dewalt motor pack, transmission and some other Misc. parts from the DewaltServiceNet. The part we are trying to work out now is a bearing system or something to handle the side loads. Also, we will be doing a shaft drive system, no chains.
|
|
#27
|
|||||
|
|||||
|
Re: CIM Voltage and Motor Suggestions
Sorry, detained for the weekend. That kind of thing will work, but I'm not 100% sure the size for the NDB trannies will work for those trannies. But you should certainly be able to get some clamps like that that are the proper size once you measure the diameter on the hammerdrill.
As for mounting, etc. I still don't think you'll be able to get a direct drive to work. I think you'll want to get atleast one of those in hand or find one at a Home Depot or tool store and make sure that if you put them back-to-back that they'll still fit on your base. That said, if you're bound and determined, you could drill and tap the end of a shaft, lock-tite it onto the spindle, drill it and roll pin it, and maybe even weld it to the spindle as well for good measure. Yes, I'm serious. This thing is going to put out a lot of torque, and I think welding might be your only chance of getting a direct shaft connection that can handle it. The problem is that your direct shaft means you can't use the left-handed screw to efficiently hold something down and keep it from unthreading. Atleast I don't see any easy way. |
|
#28
|
|||
|
|||
|
Re: CIM Voltage and Motor Suggestions
Support your shaft with your wheel or whatever it is on its own. Put half of a flex coupling (lovejoy makes good ones) on the end of it with a keyway and key for transfering torque and perhaps a set screw to prevent axial movement. Put the other half of a flex coupling threaded onto the drill gearbox output shaft. Hold it on with a left hand screw and washer. Put a flex copuling spider (insert) in between. Put the two together. Mount the drill.
|
|
#29
|
|||
|
|||
|
Re: CIM Voltage and Motor Suggestions
Ahh, I didn't think this sort of thing would be easy. The problem is, a chain drive would be too laggy switching directions to ever work for us. Direct drive has to be the way to do it.
So, let me get this straight: The mounting-clamp-thing from the NBD whitepaper will support the side loads right? I hear that side loads are bad for gearboxes, so this will protect it right? So, once we get our 5/8in shaft somehow attached to the gearbox (perhaps the way you mentioned it) it should work right? Thanks also for your suggestions, sanddrag. |
|
#30
|
|||||
|
|||||
|
Re: CIM Voltage and Motor Suggestions
sanddrag's shaft mounting should work brilliantly. I should've thought of that. at any rate, the mounting collar doesn't particularly support any side-loads. All of the load will still be supported by the shaft. With the flexible coupling, the shaft out of the drill won't support anything at all. You'll need to support the shaft in your wheel with a pair of bearing pillow blocks on the other side of the flexible coupling.
|
![]() |
| Thread Tools | |
| Display Modes | Rate This Thread |
|
|
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| Large CIM motor | Wayne Doenges | Motors | 3 | 06-03-2006 21:24 |
| Small and Large CIM Motor Data | Danny Diaz | National Instruments LabVIEW and Data Acquisition | 0 | 23-02-2006 03:26 |
| CIM motor components | natis | Motors | 4 | 13-01-2006 11:04 |
| CIM-MOTOR source | Andrew Schuetze | Motors | 6 | 18-05-2005 11:57 |
| CIM vs. Drill motor | duckshepherd | Motors | 3 | 15-02-2003 18:36 |