Replacement Parts feature
Off to a good start
100 years ago: a milestone in automotive history was unveiled
In March 1914, Bosch presented its first
electric starter motor for automobiles. This
marked a giant leap forward in automotive
electrification, which would make driving
safer and more comfortable. Electric starter
motors were a great relief for motorists of
the day. It took a lot of effort to start a heavy,
large-volume engine, but now chauffeurs no
longer had to work up a sweat cranking the
engine. What’s more, with manual starting
there was always a risk that the crank
handle might slip or suddenly kick back –
possibly causing serious injury.
who had the idea of using an electric motor
to start the engine. Other manufacturers had
already attempted to do the same; while the
results of their efforts worked relatively well,
they were still unsuitable for everyday use
and series production. So if Bosch moved
quickly, it could develop a better starter
motor of its own.
➲ Bosch has the biggest share of the world
market of starters
➲ From a few thousand to twelve million every
year: The technology has prevailed
➲ Weighed almost ten kilos: the first Bosch
starter motor “Typ R” with an engine in 1914
The electric power for the new starter
motor came from the vehicle battery,
which was part of the Bosch automotive
lighting system. Bosch had launched this
independent power supply system only
a year earlier. While the earliest starter
motors weighed almost ten kilograms and
delivered just 0.6 kilowatts of power, the
starter motors in today’s portfolio weigh
between 1.9 and 17 kilograms and cover
a power range of 0.8 to 9.2 kilowatts,
demonstrating just how far starter motor
technology has advanced.
A new line of business
“The starter motor is typical of the
products Bosch launched in the early
days of motorisation. All of them were
designed to eliminate shortcomings in
function, operation, and safety,” says Ulrich
Kirschner, president of the Bosch Starter
Motors and Generators division. It was
Gottlob Honold, Bosch’s chief engineer,
It wasn’t uncommon for motorists to come
to serious harm when, instead of turning
over, the engine would kick back a short
way and cause the heavy crank handle to
hit them. At a time when many people were
still suspicious of the recently introduced
automobile, this danger might all too
easily tarnish its public image. Owners –
predominantly wealthy individuals who were
becoming keen on driving their automobiles
themselves rather than being chauffeured
– demanded a more convenient alternative.
The new electric starter motor could be
operated safely and reliably, first by means
of a foot pedal and soon after at the touch
of a button.
Series production of starter motors
specifically tailored for use in start-stop
systems began in 2007. To save fuel, this
function stops the engine when the vehicle
is at a standstill. As soon as the driver
presses the gas pedal, the engine starts
again – quickly, quietly, and automatically.
In order to achieve further reductions in
fuel consumption and CO2 emissions,
Bosch engineers are working on gradually
extending the scope of engine shutoff. In
what is known as coasting mode, the engine
will initially be shut off whenever the vehicle
is coasting to a stop. Later, the coasting
function will be extended to stop the engine
even while on the open road, whenever the
driver’s foot is no longer on the gas pedal.
An innovation with a future
initially, most of the demand for electric
starter motors came from North America.
This was reason enough for Robert Bosch
to ramp up starter motor production at the
company’s plant in Plainfield, New Jersey
in 1914. Initially, sales of the new device
remained modest; by 1927 Bosch had
sold approximately 11,000 units. Then the
starter motor gradually became more widely
accepted, and nearly 550,000 were sold by
1933. But still it took decades for the crank
handle to disappear completely from the
world’s roads.
| words in action
40
october 2014
Ready to start at any time
Today, Bosch offers a broad spectrum
of robust, reliable starter motors for
gasoline and diesel engines – for
passenger cars and commercial
vehicles, supporting both 12 and 24 volt
vehicle electrical systems. In addition
to ease of integration, Bosch starter
motors are lightweight, compact, and
powerful, reducing fuel consumption
and emissions. Bosch manufactures
more than twelve million starter motors
every year, and these are installed
in at least one in every five newly
manufactured vehicles worldwide.