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Students invent quieter leaf blower

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Re: Students invent quieter leaf blower

#271

Post by vel0city »

tyingq wrote: post #119
Aurornis wrote: post #40

Earlier quoted context omitted.

> There's a section of folks who enjoy loud engines. It's their jam, they love being 'outdoors' with loud gas powered engines, big trucks, riding lawn mowers. It's a fantasy escape world for them. That’s an awfully uncharitable projection. The lawn business people I know would love to adopt full electric fleets of gear. They aren’t sending their teams out with gas engines because it’s a “fantasy escape world”. They d…

It sounds like the key part of the idea could apply to gas blowers, right?

A massive amount of the noise of a gas blower is the gas motor part of the thing.

Re: Students invent quieter leaf blower

#272

Post by agumonkey »

lupire wrote: post #181
agumonkey wrote: post #159

Earlier quoted context omitted.

I also assume that human operating mowing will not last long. A tiny swarm of self operating mini rovers will probably do.

That's horrific.

I meant as a job for large surfaces. Keep mowing your lawn if you want to, but in that case a battery powered one will probably be enough.

Re: Students invent quieter leaf blower

#273

Post by eyelidlessness »

willsmith72 wrote: post #207
loceng wrote: post #176

Earlier quoted context omitted.

Elon Musk at one point once suggested Tesla would make a quiet leaf blower - due specifically to the noise. I wonder if Tesla perhaps has a whole bunch of technologies they're developing incognito in the background - or if he's perhaps being limited for some artificial reasons? It may just be a market size issue - and cities passing bylaws to disallow gas powered, only allow electric under a certain dBs is the fix; a…

Is that really what people want? Leaf blowers to me are possibly the least interesting, least appealing way to use modern tech To clarify, as a research project, cool. We can probably use any new developments elsewhere. But as a tesla product, just why?

While I am reticent to speculate on anything Musk or Tesla…

> Is that really what people want?

I would literally buy substantially quieter leaf blowers, as gifts, for neighbors whom I do not even like. There are few things I want more.

Re: Students invent quieter leaf blower

#274

Post by vel0city »

datavirtue wrote: post #56
Aurornis wrote: post #40

Earlier quoted context omitted.

> There's a section of folks who enjoy loud engines. It's their jam, they love being 'outdoors' with loud gas powered engines, big trucks, riding lawn mowers. It's a fantasy escape world for them. That’s an awfully uncharitable projection. The lawn business people I know would love to adopt full electric fleets of gear. They aren’t sending their teams out with gas engines because it’s a “fantasy escape world”. They d…

I have been running the best of the best in tools and battery tech: Milwaukee. The blower and weed trimmer (especially) burn through very expensive batteries (XC8.0) very quickly. It is not a feasible replacement for even a moderate job. My yard is super small and I move quick and have learned to pull the batteries at 50% to keep from ruining them. But I have burnt up at least one $200 battery that will only charge t…

You're talking about an 18V battery, maybe up to 8Ah. About 144Wh.

My batteries on my blower and trimmer and lawn mower use 56V batteries, up to 12Ah. About 672Wh. The smallest battery I have for it is 280Wh.

Milwaukee might make some decent power tools, but they're still batteries designed for a drill or some other smaller handheld tool used for short stints. Companies focusing on lawn care products have much different battery packs.

Re: Students invent quieter leaf blower

#275

Post by flanbiscuit »

chmod775 wrote: post #237
foobarian wrote: post #158

I got an electric leaf blower mostly to avoid the noise and partly to avoid gasoline engine issues (a Kobalt 80V blower). What baffles me is that here the designers had a chance to make something truly quiet but instead they blew it and used a super-high-RPM motor-powered narrow turbine placed inside the pipe. It sounds like a dental drill amplified through a set of loudspeakers. I would kill to get a commercially de…

> What baffles me is that here the designers had a chance to make something truly quiet but instead they blew it and used a super-high-RPM motor-powered narrow turbine placed inside the pipe. They didn't change anything about the blower. They made an adapter you plug on the front that tries to cancel out the the worst offending frequencies. Like a silencer, but for leaf blowers. It's the red thing you see on the pict…

I think foobarian is referring to is:

> I got an electric leaf blower mostly to avoid the noise and partly to avoid gasoline engine issues (a Kobalt 80V blower).

...and not the content of the post. I was a little confused as well though so you're not alone. But I'm pretty sure that's what they meant.

Re: Students invent quieter leaf blower

#276

Post by jandrese »

willsmith72 wrote: post #207
loceng wrote: post #176

Earlier quoted context omitted.

Elon Musk at one point once suggested Tesla would make a quiet leaf blower - due specifically to the noise. I wonder if Tesla perhaps has a whole bunch of technologies they're developing incognito in the background - or if he's perhaps being limited for some artificial reasons? It may just be a market size issue - and cities passing bylaws to disallow gas powered, only allow electric under a certain dBs is the fix; a…

Is that really what people want? Leaf blowers to me are possibly the least interesting, least appealing way to use modern tech To clarify, as a research project, cool. We can probably use any new developments elsewhere. But as a tesla product, just why?

I want it. Specifically I want it to be mandatory for all of the lawn services that use straight pipe two stroke leaf blowers at 6 in the morning, every morning.

All other lawn equipment is loud but manageable. Leaf blowers are unreasonable. They are also the only equipment even the lawn service guys wear heating protection while using (sometimes).

Re: Students invent quieter leaf blower

#277

Post by jandrese »

Joker_vD wrote: post #221
sidewndr46 wrote: post #100

Earlier quoted context omitted.

It isn't so much the noise that bothers me, what I've never understood about leaf blowers is what are they meant to accomplish? When I watch people use them they either blow the leaves into the street or the neighbors yard. What do they think that does? Now on the other hand, I do own a very noisy leaf vacuum. But when I've collected a bag full I can just deposit the leaves in my collection container. They are taken…

Wouldn't letting the leaves to decompose be better for the soil instead of constantly removing them? I mean, the tree supposedly uses the nutrients from the soil to grow those leaves, and if you keep removing them away, at some point the tree will simply starve and die, right?

Better for the soil, but it kills off the grass.

Lawn services mostly use leaf blowers to clear driveways and sidewalks of grass clippings.

Re: Students invent quieter leaf blower

#278

Post by SoftTalker »

foobarian wrote: post #158

I got an electric leaf blower mostly to avoid the noise and partly to avoid gasoline engine issues (a Kobalt 80V blower). What baffles me is that here the designers had a chance to make something truly quiet but instead they blew it and used a super-high-RPM motor-powered narrow turbine placed inside the pipe. It sounds like a dental drill amplified through a set of loudspeakers. I would kill to get a commercially de…

They are made. Of course a hand-held blower that has enough air velocity to do its job is going to make some noise, but I walked by a landscape maintenance guy outside work yesterday, he had a battery-electric blower and it was much quieter than the old two-stroke gas blowers they were using last year. I didn't note the brand but the casing was green. Maybe Deere, but it wasn't quite the Deere shade of green so I don't know. You know what's quieter than any blower? A broom. But not as fast.

Re: Students invent quieter leaf blower

#279

Post by jandrese »

xxs wrote: post #178
sgarland wrote: post #70

Earlier quoted context omitted.

There are problems with battery-powered tools (at least, leaf blowers) still, especially at the commercial level. For one, they just don’t have the runtime. I briefly had an 80V blower. On its highest power – which is the only way it could come close to a gas-powered model, it was barely able to get all of the leaves out of the yard (we had a tree with leaves that had needle-like protrusions, which made them quite ha…

A whole hour of runtime would be mean 1C discharge. 80V (which is likely 72V, but in the US it's ok to label the max voltage rather than the actual one) is made of 20 Li-Ion batteries in series. Lets say 2 in parallel, so total 40 batteries. I'd go with 3Ah per battery (could be more for 21700) and around 2Kgs weight. For 1h work that's ~430W of power which is rather under powered. That fast charger (say 30min to cha…

For what it is worth the chargers for tool batteries are almost never fast chargers. So it takes 4 hours to charge for 15 minutes of runtime.

Re: Students invent quieter leaf blower

#280

Post by johndough »

sandworm101 wrote: post #257
foobarian wrote: post #158

I got an electric leaf blower mostly to avoid the noise and partly to avoid gasoline engine issues (a Kobalt 80V blower). What baffles me is that here the designers had a chance to make something truly quiet but instead they blew it and used a super-high-RPM motor-powered narrow turbine placed inside the pipe. It sounds like a dental drill amplified through a set of loudspeakers. I would kill to get a commercially de…

>> instead they blew it and used a super-high-RPM motor-powered narrow turbine placed inside the pipe. Because it is a handheld tool. It cannot be heavy. If you want to shove lots of power through an electric motor then that motor has to be either very heavy or very fast. The same is true for turbines. And a lighter consumer product will generally be cheaper to manufacture.

Another reason for smaller and lighter fans is the lower moment of inertia, which means faster spin up and spin down. Unfortunately, these frequent spin ups annoy me to no end.
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