That drawing I sent was a bit old. There are ongoing revisions as I sort out design issues.
MOUNTING PLATE
I chose aluminum for the motor plate/reduction gear for a couple reasons. Mostly it's easier to work with than SS. The thickness will also allow me to counter sink the heads on mounting hardware which is useful. My first idea of using the C-channel for the mounting plate was because I wanted the extra rigidity of the channel without having any welding to do. In the past I have had issues with aluminum (and SS) distortion with welding. I thought that might present a problem for belt alignment in the finished plate so I wanted to make it without any welding on that component. There would not be any fasteners threaded into the aluminum mounting plate.
The motor base will be adjustable for belt tension. That didn't show in the drawing. I was planning on milling slots for the motor mounting. Simple. The common frame plate was to facilitate good alignment.
DRIIVESAVER
The driveSaver was more for vibration reduction but I have decided it's better to make things so a proper alignment is easier and not use the driveSaver. The idea if it as protection of the drive line from impact damage wasn't a consideration. But I suppose that's why they are called DriveSavers.
Here's an interesting reference on couplers:
https://stevedmarineconsulting.com/wp-content/uploads/2019/06/ShaftCouplings179FINAL-PBB.pdf
I am building a 48V 280AH battery bank from the EVE cells that have been discussed in other threads here. They are on the way now. Here is an aluminum box they will nicely fit in:
https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2510209.m570.l1313&_nkw=393106147491&_sacat=0
I would line it with electric grade fiberglass sheet:
https://www.mcmaster.com/electrical-grade-fiberglass-(gpo3)-sheets
GENERATOR
The ME1616 has liquid cooling and as a generator should be capable of 8-10kW. Cost of the motor alone is $950. I would need a 3-phase rectifier and a regulator. I have not gotten too far in researching that yet. I have not researched the Balmar 48V alternators but I think they price a lot higher for a lot less output? More than $4000 here:
https://www.outbackmarine.com.au/power-generation/alternators/balmar-96-series-48-volt-alternators/
BELT DRIVE
I have some questions about the toothed belt drive. Originally I was planning on a 42 tooth belt on the output shaft and 16 on the motor to get the 3:1 ratio. I have an 18" variable pitch prop and want to get prop RPM at 800 for max (2400 on motor at 48V). I wondered if the 16 was a bit small and would be better with a larger pulley for more tooth engagement. If I went ot 20 I could go to 60 on the output. That also give me more flexibility to tweak the ratio with changing the motor pulley up or down from 20. The steps are proportionally smaller so more fine. That seems useful. But that 60 tooth belt is 9" in diameter on a 1" shaft. Is that a potential problem?
Carsten, You mentioned that I should not bother with stainless steel for my small output shaft. What would you suggest for that instead?
I attached another drawing showing the parts in a sequence to (hopefully) make it a little easier to understand. Some details and line weight stuff diesn't translate well to the image file but you get the gist. It's really wide to show all the parts but it's a wee little file at 250K. Also a photo of the engine bay as it looks at the moment with the old engine beds. They are not usable for this as they are too far aft because original engine had v-drive. They are also not very precisely installed. I can do better.
Dan Pfeiffer
On 2021-03-18 11:22 am, Carsten via groups.io wrote:
Dan,I have reviewed your drawings. Very interesting, a hybrid boat !When you are using a toothbelt drive, you actually don't need a Drivesaver, as the toothbelt will slip or break in a crash-stop situation. A new belt is far easier (and cheaper) to replace than a Drivesaver coupling.The inertia in an electric motor (the rotating mass) is far less than by a diesel engine with a big flywheel, and you have no gearbox anymore to worry about.The position of the ME1616 motor is almost free to choose, meaning that you can add a pulley to the shaft almost anywhere until you reach the sterndrive. The distance from shaft centerline to motor centerline is also only determined of the toothbelt length. You don't HAVE to place it in one common frameplate.If you make the motor base adjustable, it is easy to change the belt.If you make the frameplate with fixed driveshaft and motor shaft, like on your drawing, you likely will add an adjustable bearing roller to adjust the tension of the belt (same like in a car engine, for a camshaft toothbelt). Very handy too, for changes of pulleys for reduction ratio. (The roller must roll on the flat side of the belt, of course.)I guess a complete roller kit for a car is rather inexpensive.Why use aluminum for the construction?I know that it easier to cut a thread and drill a hole in aluminum than in steel.But :Steel channels and steel plates are much easier to repair if you make a mistake, or something should be re-positioned.Aluminum welding is no fun, and threads cut in steel are much stronger. You use Helicoils in aluminium constructions, if threads shall be strong and lasting. That requires special tools, so - not for a DIY mechanic.If you need something done, any workshop in any port can weld steel, and can always find a standard machine tap in the dirty drawers.I would say, that an ME1616 used as a generator might be shooting sparrows with a cannon - an expensive solution. Balmar have some 48V alternators, you can check them out.How is your plan for cooling of the ME1616 for the shaft ? (I assume that you will make a common system for the Kubota and the ME1616.)What kind of battery bank is in your plans ?Do you have a photo of the shaft and of the engine room, as it is now ?Cheers,Carsten
No comments:
Post a Comment