El Paso herald. (El Paso, Tex.) 1901-1931, 1916-04-15
WOULD ABOLISH
A DIFFERENTIAL
Axle Expert Reads Paper
That Creates Discussion
Among Motorists.

|
At the recent meeting Of the Detroi+
section of the Society of utomob
engineers. J. G. Perrin, chief engineer
or the T1mken-Detroit Axle comnaDv
read a paper on the Evolution of the
Rear Axle" and provoked a spirited
discussion OF a topic that is Of utmost
Importance today. Much interest was
displayed in the hint that before long
we may have cars without differentiaIs
as experiments are now being conduct
ed along this line.
Some of the pertinent points bro11ebt
out by Mr.. Perrin in his paper follow.
THE axle n wheel are components
OF the modern motor car that have al
ways had some equivalent in vehicles
since the rolling type succeeded the
sled as a medium for transportation.
since the axle. has always been in ex-
istence the present form is a matter of
development and evolution rather than
invention.
In some of the earlier forms Of mo-
tor propelled vehicles a belt or chain
was used for Transmitting the power
from its source to the driving wheel.
Due to the number of parts. the diff
ficulty OF arranging a satisfactory form
of housing for the chain. and the loss
OF power from belt and other forms Of
friction drives. these systems have been
succeeded by some type of positive gear
drive.
On pleasure car work the bevel gear
axle has up to this time been an exam
pie of the survival of the fittest, al
though the worm is %favorably consid-
cred when low gear reductions are re-
qJired.
The load sustaining portion OF the
rear axle has passed through A greater
number OF stages Of development than
any other part Of the unit.
Solution of Difficulty Sought.
Until about two years g the
straight tooth was the prevailing form
of beVel drive gears. With such i'm
provements in engines and transmits
sions that these units operated more
quietly, the difficulties became greater
in getting straight tooth bevel gears as
noiseless as the trade demanded. This
condition was aggravated by the in
crease IN production, which make il i'm
DOrtant that the gears operate as noise
| lessly as possible with a minimum of
adjustments, fitting n trying after a
chassis was put on the road.
Then the gear reductions, on account
of greater range Of speed on direct
drive. necessitated either small pinions
or larger driving gears. These again
| added to the difficulties of getting quiet
gears. A solution of this difficulty was
sought in two directions-the use Of the
spiral bevel and Of the worm gear.
Recently the positive drive form of
differential in which the drive is taken
on the wheel giving the best traction
has been developed commercially in sew
eral forms. The elimination Of the diff
ferential is a possibility suggested from
experiments a number of people now
! are conducting on both commercial and
pleasure vehicles.
Conduct Experiment.
THE subject is sometimes brought up
regarding the effect on axle design Of
the use of high speed six, eight and
12-cylinder engines Of small bore. When
practically the same chassis as regards
passenger carrying capacity is used the
substitution of these engines for the
larger bore engines Of a smaller num-
her Of cylinders has resulted in no
change in the fundamental dimensions
Of axle as regards size Of drive shaft.
bearings and driving bevels."
The possibility of running aXles with
out d~ifferentials was dilated upon. Mr..
Perrin said that it is being experiment.
ed with all over the country. In Eu-
rope they are running some Of the am
balances without differentials, and they
ind hat the efficiency Of the truck is
increased a great deal, as regards
straight ahead going. The only limiting
factor, so far. has been the short turn
ing radius, as trucks so equipped can
not turn around in such close quarters
as conventionally built types, because
the friction Of the parts is too great
The binding effect in trying to turn
around in too short a circle has been
too great to be satisfactory on the
rough ground. One prominent electrical
concern building electric cars, said Mr..
Perrin. has tried the nondifferential
construction in New York city and
found that the ampere draw with and
without differential was practically the
same.
Asks for Comments.
F. E. Moskovics. Nordyke & MarmOn
company. said that he noticed several
concerns are in the habit Of making
dffferentials without adjustment, and
asked for the comment Of the author OF
the paper on this subject. Mr.. Perrin
said that the other arrangement that
would have to be used, IL there were no
screw adjustment in the meshing Of the
bevel gear, is the fitting Of variable
pinion. back Of the main bevel gear.
That has been tried. he said. and it is
continued today in some cases, and
while II is perfectly feasible in small
productions, it has not proved n COM
mercial possibility in large outputs.