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What were they thinking: mowing a lawn

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Michael Lorello
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re: What were they thinking: mowing a lawn
Michael Lorello   6/27/2012 12:05:35 PM
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Upon further review of the patent (4,455,816 issued June 26, 1984), there is a gear reduction using pinion gears to drive the wheels. However, I stand by my suggestion to use a jack shaft to eliminate the gapping issue.

Peter Clarke
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re: What were they thinking: mowing a lawn
Peter Clarke   6/27/2012 12:03:14 PM
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I met a patent engineer recently... He pointed out that usually a patent is granted not for an obvious thing (like putting grass cutters on tricycle -- Boudicca and many Roman charioteers had thought of human cutters) but for something complex -- such as how the the chain drive copes with going in reverse or some other such item. But he fully acknowledged that often patents are granted for technologies for which there is prior art. He told me that patent attornies cannot know all the prior art that is out there. The result is multiple conflicting patents that have to be tested in court. However, they only get tested if a significant market develops around the technologies. The problem is that the situation as it stands encourages expensive patent filing and eventually the waste of large amounts of money in the global legal system.

Michael Lorello
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re: What were they thinking: mowing a lawn
Michael Lorello   6/27/2012 11:57:49 AM
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Here is an EE's reply to the issues brought up by bk1 and MarvA: Use a jack shaft driven by the pedal crank to transfer the power to the side right next to the wheel. Using two sprockets, drive the blades with a 1:1 to get the higher RPMs and a 1:3 to drive the wheels (perhaps a shaft within a shaft to allow the blades to spin faster than the drive axle, thus allowing both wheels to be driven). I suggest the 1:3 because you do not want this to be a fast vehicle, or else the grass cut quality will suffer. Now, where do I send my consulting bill? :)

Fabio007
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re: What were they thinking: mowing a lawn
Fabio007   6/27/2012 8:14:52 AM
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Completely agree, patents like this indicate that the patent office is not doing its job properly. Yes, this may have an inventive step (adding a grass cutter and driving mechanism to a child's bike), but seriously, who as a kid has never thought of that before, ie: where is the novelty, aka: lack of obviousness? I'm sure you could find "prior art" for this in a children's cartoon! Of course, the true test of a patent is in a court, so if you actually start selling something like this and then get sued for infringement by the patent owner, the cost of arguing the patent is invalid in a court would be prohibitively high. Besides, the patent owner gets to chose the court and there are now many pro-patent courts which tend to dramatically favour the holders of patents to the detriment of those without the patents. Then there is the true innovator, the scientist or engineer, slaving over a workbench for a lifetime, developing new products for his employer... who gets the benefit of that work? Not the engineer; its the owners of the company, who more often than not put in place an incompetent board that hire socio-pathic bosses who just want to hit share-price targets by firing legions of said good engineers, these bosses who then walk away massive bonuses just before the company crashes, leaving destroyed lives and wrecked companies in their wake... and then the same boss gets paid twice that amount to do the same thing to yet another unsuspecting company...! Yes, the patent system is broken, and I don't see anyone trying to fix it. Time for all of engineers and scientists to rise to the challenge. Yes, there is money to be made in engineering, but it isn't us engineers getting any of it. Anyone up for a financial revolution?

JefW
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re: What were they thinking: mowing a lawn
JefW   6/24/2012 1:54:14 AM
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Is this really a patent? in the 20th or 21st century? If so it's an example of all that's wrong with the patent system. This is hardly innovative. This is an un-developed doodle that picks up on an idea common to every kid who ever had to stop playing and mow the lawn. These nuisance patents seem to be given more and more encouragement as the decades roll on and in so many ways they are stifling progress and innovation!

MarvA
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re: What were they thinking: mowing a lawn
MarvA   6/23/2012 1:07:53 AM
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I pushed a mower for years when I was a kid. A serious problem with the design as shown is that the RPM of the blade is the same as that of the wheels. That doesn't work. My recollection is that the reel was always geared up at least 2x with respect to the wheels. There are obvious ways to rectify that flaw.

BrianBailey
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re: What were they thinking: mowing a lawn
BrianBailey   6/20/2012 1:31:10 PM
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But we are talking kid power here. Have them go around again!

bk11
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re: What were they thinking: mowing a lawn
bk11   6/20/2012 1:13:03 PM
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Wouldn't the gap in the blades where the chain passes through leave a strip unmowed? Apparently I've been in design review mode too long!

seaEE
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CEO
re: What were they thinking: mowing a lawn
seaEE   6/17/2012 5:03:05 PM
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Hmmm...I believe the "guidance device" would involve a lawn chair and a can of beer. :)

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