Completed in 1897, the Toyoda Power Loom, Japan's first
self-powered loom, drew acclaim for its ability to produce high quality cotton
cloth in a stable manner, and gained widespread public attention.
The Toyoda Power Loom featured a weft halting device1 which
automatically stopped the machine when the weft thread in the shuttle broke or
was exhausted.
In power looms, if the weft or the warp thread breaks and the
machine is not stopped immediately, faults can occur, such as the warp
continuing to be incorporated into the fabric without the weft, or the broken
warp thread being left out, leading to the output of damaged fabric. Sakichi
Toyoda researched systems to prevent such faults, and in addition to the weft
halting device mentioned above, also made several other inventions and
improvements, including a system for maintaining a constant tension of the warp
thread to prevent breakages, and a warp halting device to stop the loom when
the warp thread broke.
The Toyoda Power Loom released by Toyoda Shokai in 1905 was
not an automatic loom, but a so-called "regular" power loom, and
incorporated features such as those described above to prevent defects.
According to the instruction manual2 for the Toyoda Power Loom, the following
were the model's main features:
1.The warp tension controller automatically maintained the
warp output at a constant tension. This resulted in less frequent breakage of
the warp thread, reducing loom downtime and producing other benefits. In terms
of product value, fabrics had a consistently fine texture and uniform quality.
2.The loom featured a warp halting device which
automatically shut down the machine when the warp thread broke. This meant that
the machine did not have to be constantly watched, allowing a single operator
to run several looms at once. Also, quality defects such as missing or tangled
threads decreased, reducing the likelihood of damage to the fabric.
3.A weft halting device halted the loom when the weft thread
broke or ran out. As in item 2, this eliminated the need for the machine to be
constantly watched.
Items 2 and 3 aimed to prevent loss and waste from quality
flaws and reworking by automatically stopping the loom when irregularities
occurred. Sakichi’s design concepts live on even today in the Toyota Production
System as the origin of jidoka.3
Invention of the
Circular Loom and Circular Single Flow Motor
In 1906 Sakichi Toyoda invented the circular loom, acquiring
a patent for the machine the following year in 1907. Later, in 1924, he
invented a heddle for the circular loom, a shuttle-changer for the circular
loom, and a winding mechanism for the circular loom, and patented these devices
the following year. In contrast to standard looms, in which the shuttle moved
back and forth to incorporate the weft, in the circular loom the shuttle moved
in a circular motion to insert the weft, reducing energy loss and operational
noise.
Using the same concept, in 1914 Sakichi invented and
patented the circular single flow motor, which switched the back and forth
movements of steam engine pistons for a circular motion. In addition, he also
invented and patented improved versions of the circular engine in 1917, as well
as the circular single flow motor in 1920.1 Sakichi believed that circular
motion was more energy efficient than reciprocating motion, and worked to
invent circular looms because, as he saw it, "circular motion, rather than
the reciprocating motion of the past and present, is the ideal we must strive
when creating looms"
Support for
Development and Invention of Electricity Storage Devices
As exhibited in his invention of the circular single flow
motor, Sakichi Toyoda was also deeply interested in power itself. Although Japan's
first power loom, the Toyoda Power Loom used the written Japanese character for
steam in its name, its power was provided not only by steam, but also by an oil
motor. According to the instruction manual, one horsepower of output was
sufficient to drive 20 looms.
Looking at the power usage at the plants operated by
Sakichi1, the Toyoda No.1 Plant (Toyoda Shokai Office Buhei-cho Plant) in 1904
ran on one 3.5 hp oil motor, Toyoda Loom Company (formerly Toyoda Shokai Office
Shimasaki-cho Plant) in 1909 ran on one 24 hp gas motor and one 3 hp oil motor,
and in 1916 Toyoda Automatic Spinning and Weaving Plant (precursor to Toyoda
Boshoku Corporation Honsha Plant) operated on one 400 hp steam engine (300 kW)
and 720 kW of commercial electricity.
For power generation at the Toyoda Jido Boshoku Plant,
400-hp uniflow steam engines manufactured by Switzerland’s Sulzer were
installed in 1914. At that time, the installation of steam engines for
generating electricity was unusual in the Nagoya area, and Sakichi’s Toyoda
Jido Boshoku Plant and his younger brother Heikichi’s Toyoda Shokufu Oshikiri
Plant were about the only examples. When the plant was expanded in 1916, it
began to receive a 720 kW electric supply from Nagoya Electric Light.
In the 1910s, plants across Japan were in the process of
switching their power sources from steam engines and gas motors to electricity.
The percentage of power generation from electricity by Japanese weaving and
dyeing plants rose from 8.9 percent in 1909 (13.3 percent for all types of
plants) to 22.4 percent in 1914 (30.1 percent), and continued to increase
rapidly in the following years.
From the autumn of 1922 to the spring of 1923, Heikichi
traveled to Europe and the United States to observe overseas techniques, and
purchased a German-made electric vehicle.3 The vehicle was powered by private
generators, and was also used by Kiichiro on occasions. However, battery
capability at the time meant that driving time was limited even when the
vehicle was charged overnight, taking longer to charge than to deplete.
In 1925 Sakichi Toyoda asked the Imperial Institute of
Invention and Innovation to investigate the conditions and methods for donating
prize money in order to offer a one million yen prize for developing a
revolutionary electricity storage device (storage battery).
This move was spurred by the first aerial circumnavigation
of the earth by the United States Army Air Service in 1924, conducted in a
Douglas aircraft and taking 351 hours and 11 minutes of flight time over 176
days from March 17 to September 28.1 Japan was on the flight path from the
Aleutian Islands to Indochina and India.
Sakichi was inspired by this flight around the world, and
came up with the idea of offering a monetary prize for invention of a storage
battery for mobile use. Accordingly, he envisioned that the research should
focus on a storage battery used to power automobiles and airplanes. However,
development of such a storage device was extremely difficult, and as a result
of the study by the Imperial Institute of Invention and Innovation it was
decided to begin by offering research grants, and to offer the one million yen
prize money when creation of such a device became more realistic.
The contract Sakichi concluded with the Imperial Institute
of Invention and Innovation on October 15, 1925 agreed to donate 500,000 yen to
a fund over five years, and in the case where the annual interest of that fund
was less than 30,000 yen, Sakichi would provide the difference. In addition, as
a part of efforts to encourage development of a storage battery, the Toyoda
Research Office would be established within the Imperial Institute of Invention
and Innovation. This office would be the central body responsible for driving
the effort to develop the required technology. The first recruitment for
intermediate inventions took place in 1927, followed by a second recruitment in
1931 and a third stage in 1935.
Kiichiro inherited Sakichi’s expectations and thinking
concerning storage batteries, and established a battery research laboratory in
Shibaura, Tokyo and began storage battery production at the Shibaura Plant in
1939. Kiichiro also directed that development of an electric vehicle should
start, and prototype production of the Model EC electric car equipped with a
storage battery and non-combustion engine (motor) began in about 1940.
Source: TOYOTA MOTOR CORPORATION
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