The Roanoke daily times. (Roanoke, Va.) 1895-1897, 1896-12-04
ELEVATOR APPARATUS.
German Skill Has Pi oduccd n Safety Flee
trio Starter Practical and Positive.
(From the Providence Journal.)

trio Starter Practical and Positive.
(From the Providence Journal.)
One of the special features of elevator
apparatus is that the motors are very ire.
quently stopped, started and reversed.
The "lIci<tr" tcchnschc Zeitschrift" des-
cribes nu apparatus brought out by Sic
mems & Ilalske as II safety starter for
motors of this kind. This is subject which
has long engaged the attention of electri-
cal firms on the other side of the ocean.
The most usual form OF starter there is
that in which the sliding contact OF the
resistance coil moves forward from it's cen
trail position as soon ms the steering rope
is pulled by the attendant in the elevator
car, and the speed of motion can be re,ll.
lated by kind of brake. In order to les
son the bad effects caused by sparkling ut
starting and stopping. special switches
are often used. AS metal contacts were
much injured by sparkling, Messrs. Siemcn
&..HalsIe decided to use carbon, but as this
material is not suitable for rubbing con-
facts, another arrangement had to be
adopted. In the original DESIGN the ends
of spiral resistance coils were connected
to row of cylindrical carbons, insulated
from each other ard fixed to the base of
the apparatus. Above the fixed carbons
was Il row of movable carbons, each pro-
vided with spiral spring, and the whole
row was fixed to II crossbar which could
be raised or lowered. When lowered the
upper carbons made contact with the
lower contacts and the action Of lowering
cut out one resistance coil after another.
The resistance anu the carbon apparatus
were in series with the armature.
Neither sparkling ut opening or closing
nor the glow caused by the passage of
nt1rr re Il
fewer carbons than metal contacts were
needed. The large number of metal con-
facts usually employed is caused by IL de.
sire to protect from fire rather than to
avoid sudden fluctuations of current
With the usual type of ! HIP. motors,
four pairs of carbons are found sufficient.
The first type was controlled by the usual
lift gear: this moved the starting switch
from its mid position. causing current to
flow i'll the magnets In one direction, and
in the armatule according to the desired
direction of motion. The crossbar sank
by its own weight. its motion being con-
trolled by an air dash pot: this cores
ponded to the ordinary gear, but soon
gave place to the following improved
type:
Tine signal coils of the starting resist
ance must be cut out ut the same rate rs
the counter. electro-motive force of the
motor increases with speed. The posi-
tions of the carbon should therefore be
directly controlled by the speed and this
is attained by the use of II centrifugal
governor driven off the motor and actu-
ating the crossbar carrying the carbons
The gear also acts as IL safety arrange.
ment in case of accident. If the car stops
for any reason the whole of the resistance
is ut once put into circuit, and this is
much better than IL fuse, as the latter
| must be replaced when melted.
The article which is quoted in part
states that this arrangement works well,
and refers 30 six freight elevators with
seven horse power motors in II granary
at Wilhelminaquai, Rotterdam, working
with 44O volts off the town supply. Heav-
icr apparatus are made with six to nine
pairs of cartoons, and these are suitable for
motors up to 30 HIP. Two passenger
lifts have recently been put into the City
Hall, Berlin, and these are worked with
2l0 volts. The apparatus is suitable fol
| rotary currents also.