Kiichiro Toyoda orders prototype research and preparation for production

Despite the circumstance of restrictions on passenger car manufacture, Kiichiro Toyoda wished to promote technology development with a view to the future. On September 13, 1940, he therefore issued an order for research to be undertaken into prototypes and for preparations to be made for their production. The introduction to the order emphasized the need for technology development, declaring "Toyota anticipates that, as times change, a day will come when this type of production is required. We should therefore undertake research into prototype production". Specifically, a definition was given of the 'vehicle types that Toyota may produce in the future' (Table 1-11). Research progressed based on this order and, whenever there was an opportunity, passenger cars and special vehicles of the types outlined below were produced in prototype.

Table 1-11. Automobile Types Specified in the Prototype Research and Production Preparation Order (1940)

(1) Trucks

Chassis length
Engine type
3.3 m (GB Truck)
Current trucks with 75 hp
3.6m (GB Truck)
75 hp
4.0 m (4-ton capacity Model KB trucks)
75 hp or 85 hp
For lengthy cargo
85 hp

(2) Passenger cars (sedans and convertibles)

Chassis length
Engine type
Large No. 1 (Model AA passenger car)
75 hp, phased reduction of vehicles currently in use
Large No. 2 (Model AC passenger car)
75 hp, newly-designed vehicles
Medium No. 1 (Model AE passenger car)
4-cylinder vehicles currently in prototype production
Medium No. 2
Special design 2,000 cc 6-cylinder vehicles, to be designed in the future
Medium No. 3 (Model BA electric vehicle)
Battery-operated motor, currently under research
Small No. 1
2,000 cc 6 cylinders to be researched in the future and converted to 4 cylinders
Small No. 2 (Model EA compact passenger car)
D.K.W., currently in prototype production
Small No. 3 (Model EC electric vehicle)
Battery-operated motor, to be researched in the future

1) Prototype production of large-sized Model B and medium-sized BC-III passenger cars

Plans for the Model B luxury large-sized passenger car were adopted in November 1942 and the design was completed in May of the following year, 1943. The prototype of the large-sized Model B was completed and official test driving carried out in January 1944 (Table 1-12).

Table 1-12. Specifications of the Large Model B Luxury Passenger Car (1944)

Item
Description
Engine
Modified B engine (3,389 cc, 85 hp, compression ratio: 6.9:1)
Wheelbase
3,300mm
Length
5,750mm
Width
1,920mm
Height
1,825mm
Vehicle weight
2,200kg

The medium-sized BC-III passenger car completed its design phase in November 1943 and the prototype was ready in February 1944. The specifications of the BC-III are shown in Table 1-13.

Table 1-13. Specifications of the Medium-Size Model BC-III Passenger Car (1944)

Item
Description
Engine
F engine (2,585 cc, 55 hp, compression ratio: 6.0:1)
Wheelbase
2,800mm
Length
4,645mm
Width
1,750mm
Height
1,650mm
Vehicle weight
1,400kg
Note:
The F engine was a modified version of the C engine.

2) Prototype production of electric vehicle

In accordance with Kiichiro's instructions, electric vehicle development began in 1940 at the Kariya electrical components plant, where a non-combustion electric engine using glass-covered wires was produced in prototype. In August of the same year, an electric vehicle was completed which adopted the chassis of the EA small passenger car and was fitted with a storage battery made at the Tokyo Shibaura Plant and the non-combustion electric engine created in the electrical components plant. his prototype was called the EC electric vehicle and had a driving range of around 60 kilometers per charge.1

In 1941, when Kiichiro became President of Toyota Motor Co., Ltd., electric vehicles became a research item under the direct control of the President and research continued at the electrical components plant. Using the BA passenger car chassis developed in 1940, six prototype electric vehicle units were produced fitted with a storage battery and electric engine produced in-house.2

As discussed above, Kiichiro conducted research and development on storage batteries and motor, the key components of electric cars, and used these technologies to develop electric vehicles.

3) Prototype production of special vehicles

In December 1937, the Shibaura Laboratory in Tokyo started work on the design of the DC large-sized bus for mainland China. In November 1938, one prototype unit was completed, which was shipped to Tianjin in February 1939. This was a large-sized bus with special specifications, details of which are shown in Table 1-14.

Table 1-14. Specifications of the Model DC Large Bus (1939)

Item
Description
Model
6 wheels, all-wheel drive; rear double-axle four-wheel drive
Engine
A engine (65 hp, equipped with 2 engines)
Wheelbase
5,000mm
Length
8,300mm
Width
2,400mm
Height
2,700mm
Track
Front wheels: 1,950 mm; rear wheels: 1,893 mm
Chassis weight
1,850kg
Total weight
6,050kg
Seating capacity:
42 passenger seats; towed vehicle: 42 seats
Source:
Toyota Motor Co., Ltd. Manufacturing Plan Vehicle List, 'Former Tokyo Toyota Photo C (1/2)', 'Model DC Large Bus'(Toyota internal document); Ryusenkei, March 1939

In parallel with the development of the KC truck, the design of a modified version, the four-wheel drive KCY truck, began in October 1942. The prototype was completed in June 1943 and public road testing was carried out in August of the same year. The results were positive, but production was suspended after four units (Table 1-15).

Table 1-15. Specifications of the Model KCY Four-Wheel Drive Truck (1943)

Item
Description
Model
4-wheel drive
Engine
B engine (78 hp)
Transmission
4 forward gears, 1 reverse
Sub-transmission
2-speed variable
Wheelbase
4,000mm
Length
6,510mm
Width
2,210mm
Height
2,220mm
Vehicle weight
2,900kg
Source:
Toyota Motor Co., Ltd. Manufacturing Plan Vehicle List (Toyota internal document)

A plough/ski-shaped four-wheel drive amphibious vehicle whose development was based on the KCY truck was produced between November 1943 and August 1944 in a run of 198 units. The chassis of the KCY four-wheel drive truck thus became the basis of subsequent Toyota all-wheel drive technology.

In April 1944, work started on the design of the AK10 small four-wheel drive truck. In July of the same year, six prototype units were completed, but, just as preparations were under way for full-scale production, the war ended in defeat for Japan, and production plans were suspended. After the war, when it came to the development of a jeep-type all-wheel drive vehicle, the design technology of the AK10 and the remaining parts proved of great use (Table 1-16).

Table 1-16. Specifications of the Model AK10 Small Four-Wheel Drive Truck (1944)

Item
Description
Model
4-wheel drive
Engine
C engine (4-cylinder, 2,258 cc, 50 hp)
Transmission
3 forward gears, 1 reverse
Sub-transmission
2-speed variable
Wheelbase
2,300mm
Length
3,360mm
Width
1,570mm
Height
1,800mm
Track
Front and rear 1,300 mm
Vehicle weight
1,100kg
Load capacity
500kg
Source:
Toyota Motor Co., Ltd. Manufacturing Plan Vehicle List, 'Model AK10 Four-Wheel Drive Truck'(Toyota internal document)

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