6
5
2.5. Power Transmission Unit
1.Drive wheel
4.Sprocket
Power transmission unit (Fig.14) has the following main
components:
2.Shaft
3.Idler
Fig. 14. Power transmission unit
and its main components.
Example, say
*
Then distance/length (L) to cover one hectare will be =(10,000/2490)=13176'
*
Circumference of the drive wheel = 1'4"
Put seed in the boxes. Set the rate control adjustment lever as prescribed by the
manufacturer.
*
Width of machine = 8'2"
*
To cover distance (l), the drive wheel has to take turns (n) = 40.06/0.4=100.15
*
As we know area of one hectare=17639 (sq. ft.)
*
The distance (l) i.e. 1/100 of hectare will be = 131'
*
Allowing 10% slippage, the distance (l) can be covered in ‘N’ turns (n–0.1n) = 90.135
(approx.).
Roller chain
The power required to operate the seed metering devices is provided by a floating type
lugged drive wheel 1'4" in diameter and 4" in width through chain and sprockets. However,
size of the drive wheel may vary in different models. Fourteen lugs each of 1.2" height at
an angle of 900 are provided on the ground wheel to avoid slippage. Wheels are of iron
closed type or with rubber on them for better traction. This ground wheel or drive wheel is
attached to the frame in front. Traction can be adjusted through a groove and spring as
desired. Attachment of drive wheel in the front side of the frame sometimes creates
problem in the free movement of wheel due to soil or
stubble blockage or due to its location being very near to
the hook of the tractor. A motorcycle roller chain of 0.5" pitch
with 14 and 37 number of teeth on the mild steel sprocket is
provided for power transmission from the drive wheel to
seed metering devices. Power from ground wheel is
transmitted to a shaft (1:1) (Fig. 15) mounted on front
frame. From this shaft power is transmitted to seed
metering shafts (2.5:1) through the chain sprocket
arrangement. However, size of roller chain and sprocket
can vary in different models as per requirements. An idler
has been provided to tighten or loosen the chain for its smooth running.
Fig-15 Drive Wheel attached
on the Front Side
2.6. Depth-Control Packer Roller
The size of these wheels may vary in different models. With
the help of depth adjusting pin (Fig.16b), these wheels can
be raised or lowered to increase or decrease the depth of
seeding, respectively. The depth of seeding in case of
wheat varies from 1.2"–2". However it can be adjusted as
per requirement.
If there is a large amount of loose straw in the field, these
depth wheels can get jammed with the straw. If this
happens, the depth-control wheels can be removed and
depth control maintained with the tractors’ hydraulics, to
reduce straw jamming.
2.7. Hitch Points
The drill has three standard hitch points; two lower
and one upper (Fig. 17). The machine is attached
to tractor through these three hitch points with the
help of link pins. The top link hitch point also helps
in leveling the machines
Fig. 17. Hitch points.
(Fig. 16a) Depth-control packer roller
(Fig. 16b) Depth-adjusting pin
2. Conversely, No Till Multi Crop Drill machine does not work well in fields where moisture
levels are too high (wheel slippage) and under such situations care must be taken to
prevent blockage of seed tubes.
3. Heat stress at grain filling is less in late winter season when temperature begins to rise.
The overall growth period of crop is more in early sowing.
4. Longer duration varieties such as PBW 343, HD 2687 having better vigor at early growth
and profuse cultivating cover the soil surface and are more competitive with weeds.
2.8 Precautions For Use
1. Sowing of wheat with No Till Multi Crop Drill is best accomplished when soils have 3-4%
more moisture than under conventional method. Germination of wheat and corn crops is
adversely affected if the soil is too dry.
5. The quantity of seeds are use in hopper by standard.