Abby’s Guide > Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) > Discussions > The "Friction Wheel" versus The Hydrostatic Transmission drive debate
Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions |
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New_Yorker
Preach the Gospel always, use words when necessary
Location: Long Island, NY
Joined: Nov 26, 2010
Points: 219
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The "Friction Wheel" versus The Hydrostatic Transmission drive debate
Original Message Dec 19, 2011 8:40 am |
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I never realized that by explaining how the friction wheel drive on another thread would cause such feelings of inadequacy in one poster that he felt compelled to pretend I had personally attacked him, which was never my intention. But now that this has come to be a subject worthy of discussion, let's explore the comparison. Most snowblowers of the two stage variety use the very simple, easy to understand friction wheel drive to propel them. Here then is the system explained so we all can begin with a clean slate. The snowblower engine drive shaft will have a pully on it to drive a Vee belt that is attached at the other end to a 'Drive Plate'. So long as the engine is running, the plate is spinning thanks to that belt. The wheels or tracks of the snowblower are connected to the drive system through a rubber faced friction wheel that rides at right angle to that 'Drive Plate', and the shaft the 'rubber faced friction wheel' rides on is one the rubber wheel can slide along from one side to the other. That sliding motion then positions the rubber tire like friction wheel on the 'Drive Plate' depending on where you place it. This is done with the cable running from the notched speed change lever on the operators console of the machine. When you, the operator, squeezes the handle that engages the drive you are lifting that engine driven 'Drive Plate' into contact with the rubber faced 'Friction Wheel' and if the rubber is in good condition, and properly adjusted , it makes contact with the drive plate and the snowblower will begin to move. How fast or whether you move forward or reverse is dependent upon that speed control that usually has something like 6 forward speed noitches, and two reverse. That cable running to the friction wheel will allow it to ride across the drive plate at the center, for low speed, closer to the edge for high speeds, and even on the other side of the drive plate's center to make the friction wheel spin the opposite direction. This puts the machine in reverse. This then is what plays the role of a transmission on all 'Friction Wheel Drive' snowblowers. The problem is that if the drive belt slips, the machine will not move. If the rubber tire like friction wheel becomes hard and glazed, it will not properly grip the flat metal Drive plate, and you again, won't move. In fact if the plate surface is slick from wear, or the friction wheel rubber is worn down, like when the tire on your car becomes bald it will again not properly contact the drive plate and transfer the engines power to those tracks or tires. Usually before this occurs you get a period of use when the machine requires the operator, You, to push it when it encounters greater resistance. So it may move forward until it has to push itself into that heavy salt laden "end of the Driveway" pile, and then the friction wheels reduced 'Friction' ability causes it to spin no longer as the drive plate becomes polished from rubbing against the immobile rubber surface. Here you have two options, first is you shove the 200 pound machine into the snow, or second, you stop, take it back into the garage where you better have the new friction wheel rubber and the tools and know how to replace the worn one that has rendered your snowblower useless. This happens to such machines as a result of normal use, and depending upon how much wear that friction wheel suffers from the normal use of the machine. Thus a snowblower moving light powder all the time will go much longer than the same machine used to throw, and push itself into wet heavy snow which wears the friction wheel more, and thus wears it out much faster. If you happen to live in a climate where the snow is often wet and heavy, rather trhan light and fluffy powder, you should evalutae your ability to deal with this maintenance item. Your owners manual will supply the repair procedure for this in most cases, as well as a parts diagram so you can order, and have on hand the necessary new rubber tire for that friction wheel. The manufacturer supplys that information precisely because they recognize the fact that your snowblower will, at some point, require this work be done. I personally understand all this from about ten years owning an Ariens Snowblower, followed by 15 years with an MTD built Sears Craftsman snowblower, both with the same friction wheel drive mechanism. Where I live in southeastern New York State, wet heavy snow is the rule, light fluffy powder is the exception. This resulted in having to change these friction wheel rubbers about every two years on average, so my next new snowblower choice eliminated the problem entirely, albeit at some considerable cost. The alternative system employs an actual 'Transmission'. My John Deere Lawn Tractor ( X-300R) has such a transmission, and it has been problem free for many years. So I paid as much for a new Honda, hydrostatic Transmission Driven snowblower (HS 928 TAS) as I paid for that John Deere tractor. The extra cost to me was worth it. Now I do not tell everyone to buy the same machine I did, or even to avoid the friction wheel drive system common to most other snowblowers. I simply think that BEFORE you spend the money on that new snowblower you know what you are buying. The manufacturers, store clerks, and even Consumer Reports magazine will NOT tell you, as I just did, the Reality of owning those simple less expensive drive systems. By reading this you now understand : A)- How the thing works, B)- What To expect, and WHY, and C) - You now can buy based on an Informed Choice without discovering the hard way what will happen from normal use to your snowblower.
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royster
" It is the use of power tools that separates man from animals"
Location: New Brunswick, Canada
Joined: Feb 11, 2011
Points: 284
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Re: The "Friction Wheel" versus The Hydrostatic Transmission drive debate
Reply #21 Dec 19, 2011 7:16 pm |
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We have all been informed how the "Friction Wheel " works, The friction wheel is a simple design , dependable and economical used on thousands of snowblowers, over many years. I would like to explain how the "Hydrostatic Drive" works in my Husqvarna although most people already know how this drive system works, being in most riding tractors. Like most snowblowers, there are 2 levers: auger control lever and traction drive control lever. The auger control lever is the same as on the friction drive machines. squeeze down to activate the impeller/auger and let it up to stop the impeller/auger. The traction drive control lever only sends the power to the hydrostatic transmission The third lever is the drive speed control lever , this controls the forward and reverse speeds, it is variable, has no set positions. Neutral is between forward and reverse To move the snowblower forward after holding down the traction drive control lever, move the drive speed control lever forward from the nuetral position, move the lever back to go in reverse. Declutching the traction drive control lever is not required . The hydrostatic transmission consists of the engine driven hydraulic pump and a hydraulic motor in one unit. When operating the drive speed control lever you are adjusting the amount of oil and flow going to the hydraulic motor from the hydraulic pump. allowing you to go forward or reverse as required. The advantages of the hydrostatic transmission are many: After the traction drive control lever is held down, no further use of it is required to move the snowblower, until you stop snowblowing, The speeds are variable, you can shift from forward to reverse and back without declutching. The hydrostatic transmission allows the snowblower to go much slower than the friction drive, but still have the same power to the wheels (at all speeds ,Torque is increased 20-1) While blowing heavy snow at the end of the driveway, this slower( full power) speed will easily out perform a frictiomn wheel drive. Last winter my neighbour and I made comparisons at the EOD, His new John Deere and my Husqvarna have identical Briggs 1450 engines , both are 27 inch. I could easily go through the EOD snow without stopping in a single first path, my neighbours friction drive, in its lowest gear had difficulty doing that, he had to back up twice , his wheels were spinning but he was having a difficult time moving forward. , he was jerking his machine from side to side and trying to push it forward.. My engine speed and noise remained the same all the time, while his was speeding up and down on the governor and making a lot of noise. These hydrostatic transmissions are dependable but if anything goes wrong, they are more expensive to repair.
This message was modified Dec 19, 2011 by royster
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royster
" It is the use of power tools that separates man from animals"
Location: New Brunswick, Canada
Joined: Feb 11, 2011
Points: 284
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Re: The "Friction Wheel" versus The Hydrostatic Transmission drive debate
Reply #26 Dec 20, 2011 2:50 pm |
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Maybe so, but something doesn't sound right.
I've moved a lot of snow in my day, including five foot high e.o.d. using a few brands of machines with regular friction wheel drive. Some jobs were tougher than others and some machines were nicer to use than others but I've yet to experience the difficulties you've mentioned. I have used many different makes of "friction wheel" snowblowers in various sizes over the years to do the end of driveway snow, but none have done the job as easy as my hydrostatic Husqvarna.
I am nothing against any friction drive machine, most do a fine job, but in my opinion , It is not as easy as with hydrostatic drive.
This message was modified Dec 20, 2011 by royster
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