Arrangement for recycling air in an agriculture machine
An agricultural machine including a seed metering device to meter seeds for the distribution to the ground across which the agricultural machine moves. The seed metering device embraces a wall that is arranged to rotate. The seed metering device is furthermore arranged to communicate with a pressure actuating appliance for providing a wall pressure difference between a seed reception side, high-pressure side, of the wall and a side, low pressure side, of the wall that is opposite the seed reception side. The wall is provided with a plurality of through retention openings for the reception on the seed reception side of the wall, by the wall pressure difference, of seeds at the retention openings. Then, the seeds are transported, by the rotation of the wall, through a wall transportation distance whereupon they are released from the wall. The pressure actuating appliance includes a pneumatic device connected to an air line, which device provides a main air current through the air line toward the seed reception side of the wall. A return line is connected between the side of the wall that is opposite the seed reception side and the pneumatic device, in which return line a part of the main air current is arranged to be brought back to the air line and/or to an inlet side of the pneumatic device, while a part of the main air current is arranged to be directed down into the ground through a dump line.
1. An agricultural machine comprising:
a seed metering device to meter seeds for the distribution to the ground across which the agricultural machine moves;
a pressure actuating device;
an air line;
a return line; and
a dump line,
wherein the seed metering device includes a wall that is arranged to rotate, the seed metering device is arranged to communicate with the pressure actuating appliance to provide a wall pressure difference between a seed reception side of the wall and an opposite side of the wall that is opposite the seed reception side, wherein the pressure is higher on the seed reception side than on the opposite side,
wherein the wall is provided with a plurality of through retention openings for the reception on the seed reception side of the wall, by the wall pressure difference, of seeds at the retention openings for subsequent transportation, by the rotation of the wall, through a wall transportation distance and releasing of the seeds,
wherein the pressure actuating appliance comprises a pneumatic device connected to the air line, wherein the pneumatic device provides a main air current through the air line toward the seed reception side of the wall,
wherein the return line is connected between the opposite side of the wall that is opposite the seed reception side and the pneumatic device, and
wherein a part of the main air current is arranged to be brought back to an inlet side of the pneumatic device through the return line, while a part of the main air current is arranged to be directed down into the ground through the dump line.
2. The agricultural machine according to claim 1 , wherein the dump line is connected between the seed reception side of the wall and a ground member for diverting at least a part of the main air current.
3. The agricultural machine according to claim 1 , wherein the dump line consists of a seed metering line through which seeds are directed down to the ground.
4. The agricultural machine according to claim 1 , wherein a branch return line is connected between the dump line and the pneumatic device.
5. The agricultural machine according to claim 4 , wherein the branch return line is connected between the dump line and the return line.
6. The agricultural machine according to claim 4 , wherein a seed screen is placed between the dump line and the branch return line.
7. The agricultural machine according to claim 4 , wherein a first valve is placed in the branch return line arranged to regulate the air current between the dump line and the pneumatic device.
8. The agricultural machine according to claim 1 , wherein a fresh air line is connected to the return line, wherein the supply of fresh air is regulated via a distributor valve placed between the return line and the fresh air line.
9. The agricultural machine according to claim 1 , wherein, in a positive pressure system, most of the main air current is directed from the air line back to the pneumatic device via the return line.
10. The agricultural machine according to claim 1 , wherein, in a negative pressure system, most of the main air current is directed from the pneumatic device to the dump line, while the rest of the air is directed back in the return line.