A vegetable seeder mainly consists of a seed box, seed metering device, furrow opener, soil covering device, and press wheel. These components work together to complete the sowing task.
1. Seed Supply: Seeds are placed in the seed box, a container for storing seeds. The capacity of the seed box varies depending on the model and design of the seeder. The bottom of the seed box usually has an opening connected to the seed metering device, providing a seed source for subsequent seed metering operations.
2. Seed Metering Process: The seed metering device is one of the core components of the seeder. Its function is to discharge seeds from the seed box according to specific requirements. Common seed metering devices include mechanical seed metering devices and pneumatic seed metering devices.
- Mechanical Seed Metering Device: Utilizing the principle of mechanical transmission, the seed metering components are driven by gears, chains, and other mechanisms to achieve quantitative seed discharge. For example, the seed metering device with a seed tray wheel has many seed trays on its surface. When the seed tray wheel rotates, the seed trays scoop up the seeds and carry them to the seed outlet for discharge. This type of seed metering device has a simple structure and low cost, but its seed metering accuracy is relatively low, making it suitable for vegetable varieties with less stringent sowing precision requirements.
- Pneumatic Seed Meter: This type uses airflow to adsorb and transport seeds. It uses a fan to generate negative or positive pressure, adsorbing the seeds onto the seed metering disc or tube and discharging them at regular intervals. Pneumatic seed metering devices offer high seed metering accuracy, enabling single-seed precision sowing, and are suitable for most vegetable varieties, especially those requiring high sowing precision.
3. Furrow Opening: The furrow opener is installed in front of the seeder, its function being to create a suitable furrow in the soil. There are many types of furrow openers, such as hoe-type furrow openers and disc-type furrow openers. Hoe-type furrow openers have a simple structure and strong soil penetration, suitable for harder soils; disc-type furrow openers offer good furrow opening results with neat furrow walls, suitable for various soil conditions.
4. Seed Dispensing: The seeds discharged by the seed metering device are transported through the seed delivery tube into the furrow opened by the furrow opener. The seed delivery tube is designed to ensure smooth seed descent while minimizing seed damage.
5. Covering and Compaction: After the seeds fall into the furrow, a covering device covers them with soil from both sides of the furrow, providing a suitable growing environment. The covering thickness can be controlled by adjusting the position and angle of the covering device. A compaction wheel then compacts the soil after covering, ensuring close contact between the seeds and the soil, which facilitates water and nutrient absorption and improves germination rate.
