Farm Power & Machinery

Seed drill

Seed drill is a machine for placing the seeds in a continuous flow in furrows at uniform rate and at controlled depth with or without the arrangement of covering them with soil.
The different functions of seed drill are:
• To carry the seeds.
• To open furrow to an uniform depth
• To meter the seeds
• To place the seed in furrows in an acceptable pattern
• To cover the seeds and compact the soil around the seed.
• Seed cum fertilizer drill
Seed drills, fitted with fertilizer dropping attachment, distribute the fertilizer uniformly on the ground. It is called seed cum fertilizer drill (Plate : 16.1 and 16.2) Such a drill has a large seed box which is divided lengthwise into two compartments, one for seed and another for fertilizers. Seed drill may be classified as (i) Bullock drawn (ii) Tractor drawn.


Fig: 16.1 Tractor drawn Seed cum fertilizer drill and Fig: 16.2 Seed cum fertilizer drill in operation
Depending upon the method of metering the seeds, bullock drawn seed drill can be further divided into two groups based on the type of seed dropping as by hand or mechanically. There are a number of bullock drawn implements which are used for sowing seeds in which seeds are dropped by hand. The most popular implement is three lined cultivators with seeding attachment. In different parts of the country it is made in different sizes and shapes.
Components of seed drill

A seed drill with has mechanical seed metering device mainly consists of :
(i) Frame (ii) Seed box (iii) Seed metering mechanism (iv) Furrow openers (iv) Covering device and (vi) Transport wheels.
Frame
The frame is usually made of angle iron with suitable braces and brackets. The frame is strong enough to withstand all types of loads in working condition.
Seed box
It may be made of mild steel sheet or galvanized iron with a suitable cover. A small agitator is sometimes provided to prevent clogging of seeds.
Covering device
It is a device to refill a furrow after the seed has been placed in it. Covering the seeds are usually done by patta, chains, drags, packers, rollers or press wheels, designed in various sizes and shapes.
Transport wheel
There are two wheels fitted on the main axle. Some seed drills have got pneumatic wheels also. The wheels have suitable attachments to transmit power to operate seed dropping mechanism.