Deleted
Joined: January 1970
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Post by Deleted on May 2, 2012 1:40:54 GMT -5
Yep if you don't need to alter pressure just set it , then yep straight relief will do fine..... you could make it even simpler and just use hydraulic check valve and adjust the spring in that. The flow through would be more than you need, in line, and take up less space
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Post by Johansson on May 2, 2012 6:00:57 GMT -5
That would probably work, I guess the pump will have to work less with a "real" regulator though so to save amperage it is probably the better solution. I will still have some problems fitting enough battery capacity to the bike, three oil pumps, a fuel pump etc etc will need plenty of juice... Cheers! /Anders
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Deleted
Joined: January 1970
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Post by Deleted on May 2, 2012 10:58:42 GMT -5
Well i would have look at the racing batteries, more power to weight as for oil relief..... is the oil going through 90 degrees, once you have fitted relief are you going to need to ajust it ? The reason i as is direct and in line is always better, putting oil through 90 degrees reduces the flow and all other little issues. the only more traditional oil relief go through a block is to take screw adjustment, which sits at the back of the spring to load it. Think you could save some weight and space. Using checks with a rated spring is a reconised use as relief in hydraulics. have a look at the link, you can see the flow rates are plenty high www.isis-fluid.co.uk/wp-content/uploads/catablog/fullsize/2012-202.pdf
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Post by turbochris on May 2, 2012 11:50:11 GMT -5
I mentioned this before but I'll mention it again as I would really like someone else to try this- Hook the pump up direct to the bearings with no pressure bypass/regulator/whatever. Then power the pump through a current regulator. I found the current/oil pressure relationship is almost linear. In other words, I found that despite any changing conditions such as oil viscosity and turbine rpm, it always puled x amount of amps for a given oil pressure. The voltage to the pump had to be increased as the oil thinned but the current remained fairly constant for a given pressure. If I put say a fixed 10 volts to the pump, the oil pressure and current draw dropped as the oil heated up. When I put a constant 6 amps into the pump the voltage went up as the oil thinned and the pressure changed very little. I think this would be the most compact and efficient system. How card could it be to build a current regulator that can handle less than 10 amps?
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Deleted
Joined: January 1970
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Post by Deleted on May 2, 2012 12:30:03 GMT -5
Hi Chris.... erm don't think pwm on oil pump best, pumps are rated at there design rpm, pressure and flow. you can still get high pressure at slow rpm, depending on the leakage back past pump gears etc, but the flow will suffer, and it flow we need as well as pressure. The flow rate determine the dwell time, and the rate at which the oil take the heat away, to low and the oil gets over hot and can break down, or two fast and does not take out then heat that is needed. It can be made to work with pwm but would have to spend time sorting out, but would you have a trip pot to set the oil pressure ? Richard got round this using a pressure transducer, with simple linear wire wound potentiometer to a pwm speed controller, using P2 pressure to control it..... his works well, but tuck a little sorting
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Post by Johansson on May 2, 2012 13:55:08 GMT -5
Aha, now I see how you mean with the check valve! That would work perfectly, the only downside is that it is trickier to adjust than the screw adjusted type I am working on. If I hadn´t already started to make this one I would go with the check valve type instead, but milling is fun and I have no project deadline to meet so making my own is kind of more rewarding. The oil inlet and outlet ports are in line so no bends at all, the return oil runs through two 90° bends before leaving the regulator.
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Post by Johansson on May 2, 2012 14:00:10 GMT -5
Chris, I would never trust a PWM controlled oil pump after all the trouble we have had with the electronics on our jet kick. My fuel pump is PWM regulated but if that fails the engine stops without any damage to it.
I will get Lithium race batteries for the bike, a regular lead battery would never fit and the weight would be horrible.
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Post by Johansson on May 3, 2012 16:26:42 GMT -5
I made the rest of the AN fittings today and welded them to the regulator body. If I hadn´t burned up my right thumb on a firecracker this weekend I could have done much more, it is almost impossible to work the lathe and belt sander without bumping it into something and spend the next couple of minutes inventing new curse words... ;D Cheers! /Anders
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Post by racket on May 3, 2012 19:24:46 GMT -5
Hi Anders
LOL........you're suppose to throw the firework not hang onto it ;-)
Love those coloured fittings
Cheers John
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Post by Johansson on May 3, 2012 23:45:02 GMT -5
Hi John, Ha ha, actually the cracker had a scratch type fuse (like a match) but I only had a lighter to light it with. When the fuse went off it burned like a safety torch right into my thumb... I would probably have seen that one coming if I were a tad more sober... ;D The anodized AN couplings are sweet, too bad they are so damn expensive.
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Post by racket on May 3, 2012 23:53:20 GMT -5
Hi Anders
Heh heh , so it only started to hurt the next day when you sobered up ;-)
Cheers John
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Post by Johansson on May 5, 2012 16:35:57 GMT -5
Exactly, sobering up caused all sorts of pain the next morning. I made an effort to drain my red wine bag-in-box today and ended up in the workshop making an underpressure gauge coupling for the scavange pumps, life sure works in mysterious ways... ;D Cheers! /Anders
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Post by racket on May 6, 2012 18:30:49 GMT -5
Hi Anders
Ah, .... the "wine cask" ..............a great Aussie invention , designed so the ever present flies here in Oz can't get into the wine "bottle" when having an outdoor BBQ .................LOL, just thought you'd like to know that bit of trivia :-)
Cheers John
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wolfdragon
Senior Member
Joined: April 2011
Posts: 287
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Post by wolfdragon on May 6, 2012 19:31:35 GMT -5
now i just forgot something useful for everyday life...
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Post by Johansson on May 6, 2012 23:57:29 GMT -5
Me too, something just dropped out of my left ear and suddenly I cannot for my life remember the name of the street where I live.. ;D
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