
Gleason Type Gears?
#1
Posted 09 March 2000 - 08:53
In the interim, I ask on this forum, what are "Gleason" type teeth in a final drive?
Advertisement
#2
Posted 10 March 2000 - 01:22
The only thing I could find on Gleason Gears. They are a US firm in buisness for 132 years and developed Hypoid Gears what ever that is.
Art NX3L
#3
Posted 10 March 2000 - 01:28
The Hypoid gears may be the spiral cut gear teeth rather than straight cut bevel gear teeth. This is only a guess.
Art NX3L
#4
Posted 10 March 2000 - 01:39
If Hypoid gears are spiral cut the advantage would be. Maximum contact of the teeth and minimun back lash=much stronger than straight cut bevel gears.
Art NX3L
#5
Posted 10 March 2000 - 03:48
------------------
Ursus
Trust me, send money.
#6
Posted 10 March 2000 - 03:55
Art NX3L
#7
Posted 10 March 2000 - 05:13
Helical gears are used primarily because they run quieter than straight-cut gears and hence are more appropriate for road applications. Racers prefer straight cut gears because they are lighter and more compact than helical gears. In addition straight cut gears do not put significant side loads on the input and output shafts allowing simpler bearings that do not have to deal with the thrust loadings. As well, helical gears are stronger in one rotational direction than the other making them vulnerable to breakage if asked to transmit engine braking loads, which are considerable in an F1 car.
Honda has used an interesting compromise in some of their street bike engines where they split the straight cut timing gears and spring load the two halves against each other. This quiets the gears by reducing lash, keeping the teeth in continuous contact.
#8
Posted 10 March 2000 - 05:39
Art Nx3L
#9
Posted 10 March 2000 - 11:15
I believe hypoid gear sets were developed for the Packard company in the late twenties so they could lower the drive shaft and as a result lower the floor of their car.
#10
Posted 10 March 2000 - 12:13
Art NX3L
#11
Posted 10 March 2000 - 14:31
Just to add a little to some of the side comments above - yes, race car gears - ie. first, second, third etc - are straight cut. They are stronger, noisier and easier to make (insignificant). Stronger is the key.
In every differential I have ever seen however, the hypoid crownwheel and pinion set is in evidence (also described as a 'spiral bevel' gear). And I've seen inside a lot of Hewlands and Colottis and so on. They are, of course, universal, in road cars (as far as I know), except in the Peugeot up to the last of the 404 sedans, which continued with the worm drive arrangement so popular with many car makers into the twenties, and with some truck makers for longer than that.
There is no doubt that the off-centre contact between the pinion and crownwheel - ie. the lowered driveline - can be a factor in choice.
Anyone wanting to see the alternative readily need only look at a Ford diff up to 1947, Ford being one of the very last people to adopt the hypoid final drive gears.
#12
Posted 10 March 2000 - 15:13
#13
Posted 10 March 2000 - 16:57
I notice that you're usually right on the pace and have a lot of background knowledge, but in this instance I think you might be going on instinct instead of knowledge.
But we'll ask the other experts - but only the ones who know - isn't it all calculated out so that there is no 'wiping' action?
------------------
Life and love are mixed with pain...
#14
Posted 10 March 2000 - 17:14
[This message has been edited by desmo (edited 03-10-2000).]
#15
Posted 10 March 2000 - 08:41
Gleason I believe are more modernly also involved in the Gleason/torsen diff as used by Audi in some (all?) of their Quatros and Mazda in their latest incarnations of Rx7 and Mx5.
The torsen uses "worm" gears in the centre of the diff which allows up to 5:1 torque biasing but no lock. That is its not a limited slip or locking diff but it does give very positive drive to both wheels - assuming one is not in the air.
Great traction, smooth operation, but a little wastefull of power (they do run hot) due to the sliding action (rather than a more efficient rolling action) of the gears while differentiating.
For racing purposes they tend to be weak or heavy or even both together.
Gleason have a long and interesting history.
#16
Posted 11 March 2000 - 01:36
Straight cut spur gears Are very strong. If we could mount the V 10 cross ways in the chassis we could eliminate the ring and pinion. But that isn't practical so we are stuck with what we have.
Art NX3L
#17
Posted 11 March 2000 - 02:03
Honda had a transverse V12 in F1 - so a transverse V10 would be possible, it's just not desirable.
Ray,
Gleason differentials use a spiral worm gear to load a torque biasing device. Other manufacturers have employed a face cam and pin to load Belleville type washers which in turn drive thro multiplate friction systems. Full lock up differentials may use the ratchet and pawl, or a version of the sprag clutch.
Gleason manufactured gear shaving machines which produced "generated form" gear teeth as opposed to hob milling or single point shaving!
Nomatterhowhardyatryyacantpolishaturd!
Billy G
#18
Posted 11 March 2000 - 06:32
I'm talking about 1932, not what they do now. Thanks for your information, anyway - keep up those attempts!
------------------
Life and love are mixed with pain...
#19
Posted 11 March 2000 - 08:53
No need to be so discourtious! 1932 or 2000, Gleason are still responsible for the 'generated form' tooth that made the Hypoid gear accurate, quiet running, durable, and affordable. Now ya just gotta take ya hat off to that - even if it is a 'corker'
These days (Y2K) the Gleason name is associated with the torque biasing differential that uses worm gears to load the bias mechanism.
I apologize for living in the 'here and now' and not reading your opening line to the full but living in the 'here and now' is probably why I'm 'going on 60, feeling 16'!
Oh - as a by, the polishing is done by the junior facility staff.
Hangyaganzyontneckiesneck!
PS Have a nice week end, I'm off to Lake Havasu now to work on a new compound!
Billy G
Advertisement
#20
Posted 11 March 2000 - 10:02
In a transverse box, the first gear set is a simple, on axis bevel gear pair that turns the drive 90 degrees (or transverse). The transmission shafts are both mounted transversely in the gearbox (instead of longitudenal as in most Hewland boxes). The final drive gear set is then a simple straight cut gear set.
The disadvantage of this layout is that it forces the gears to be in front of the differential.