I was going through stuff from my dad's estate recently, and I ran across a plastic bag containing twelve of these:Just based on some digging on the internet (Google is my friend as well as my enemy! ) I'm thinking they're safety caps for lead-acid batteries. I'm getting twitches on uses as diverse as private airplanes and power-chairs, but the strongest click I get is race cars, especially off-road. They seem to consist of a hollow plastic shell, vented top and bottom, with a metal ball or plug inside that slides to allow pressure ventilation under normal operation and block leakage in case the battery is turned over.Any of you boys ever seen or heard of these things? I have 12 of them brand new, with gaskets.
Yep. and they actually work. I sold a load of T-120 Trojan batteries to a golf course that needed about 100 batteries replaced, of course I needed the cores, so when it came time to do the exchange the owner was screaming at his employees to grab those damn caps, they cost me a lot of money.He swore by them, and the proof was in the cart, no acid, or corrosion, just the minimal gassing that ate some paint from over charging.And that's not normal in electric golf carts, from all the bouncing around.I don't know if you can still get those particular ones, but the new and improved versions that recycle eve the gasses, but at twelve bucks a pop, not really worth it.Hang on to those, and use them, and by all means, avoid maintenance free batteries.
Here's the problem. My caps are threaded, and almost no batteries have threaded cells these days. Most are smooth throats, and the caps just push in.I'm beginning to think I've just got a dozen anachronisms. What the hell, I'll put 'em on eBay and maybe get a couple bucks.
I'll be damned. Either they were a specialty item, or they're from the 40s or earlier, maybe even an aircraft or boat.Hell, they might be worth something to a collector, if not, you're the only guy on the block with threaded battery caps, that must be worth an hours worth of serious discussion over a beer. Now that I think about it, the only threaded battery tops are motorcycle, or small tractors etc. that I remember ever coming across in the last 30 years.OK, now you've piqued my curiosity, so I'm doing sum searchyn..
Found this, and as I suspected, around the 40s for aircraft and race cars.http://www.clubcobra.com/forums/originality-forum/121465-real-faux-g-35-rebat-batteries-how-guide.html
LOL! I already found that article -- in fact, that's where I lifted the photo I used in the OP. Based on what that guy said, the caps I have are of a more recent vintage than the ones with the fine threads. Next time I get into town, I'll stop at the NAPA store and show one of these to the old geezer that runs the place. (He's older than me! ) I'll bet he'll have the answer.
Found this patent by Gill battery, the cap resembles the one you have, though I thought your's was older, maybe not.Click on the pic.https://encrypted.google.com/patents/US2717610https://encrypted.google.com/patents/US2717610
Dead link -- '404 not found.'
Hmm...404. That’s an error. The requested URL /patents/US2717610https://encrypted.google.com/patents/US2717610 was not found on this server. That’s all we know.
Try reply #9
Weird. Try this one.https://encrypted.google.com/patents/US2717610
That link works. But as you can see by looking at Figure 1 below, the threads on my caps are radically different. I still think mine are a later design, if for no other reason than I know Dad didn't race cars or fly airplanes -- ever. But he did farm starting in the 1970s (thinking tractor battery), and later he had three different powerchairs.