The present invention concerns a disinfecting apparatus for an automatic potato planting machine, in which machine the potatoes are fed by means of bands or chains one at a time from a potato container into the planting tubes of the machine.

In prior art, potatoes were disinfected so that powdery disinfecting agent was spread manually over the potatoes as long as the potatoes were still in the potato container. This resulted in a very uneven treatment of the potatoes so that some of the potatoes remained com¬ pletely untreated, whereas others received a highly e ^' xces- sive dose of the disinfecting agent. Moreover, said procedure involved a great risk to health, because, as is well known, all disinfectants are classified as poisons.

The object of the present invention is to eliminate all of the above problems, which is achieved by means of a disinfecting apparatus that is character¬ ized in that the disinfecting apparatus comprises a con¬ tainer for a powdery disinfecting agent, a mixing chamber communicating with the container through a dosimeter, a blower connected to the mixing chamber , and connecting pipes passing from the mixing chamber into each of the planting tubes in the potato planting machine.

The further characteristics of the invention come out from the accompanying claims 2 to 5.

In the following, the invention will be de- scribed in more detail with reference to the accompanying drawing, which shows an exemplifying embodiment of a disinfecting apparatus in accordance with the invention, mounted on a potato planting machine provided with four planting tubes. The disinfecting apparatus in accordance with the invention comprises a container 1 for the powdery disinfecting agent and a mixing chamber 3 communicating

with the container 1 through a dosimeter 2, in which said mixing chamber the disinfecting agent is taken into a strong turbulent air flow from a blower 4 connected to the mixing chamber 3 and is carried from the mixing chamber 3 along separate connecting pipes 5 to each of the planting tubes 7 in the potato planting machine 6 , into which said tubes one potato at a time is fed from a potato container 11 by means of bands or chains 8. By means of this arrangement, it can be guaranteed that each potato is treated separately with the disinfecting agent as it passes through the air-powder curtain in the planting tube 7 concerned.

In order that the disinfecting agent should be supplied to the dosimeter 2 as completely and uniformly as possible as long as there is any disinfecting agent left in the container 1 , the container should preferably be f nnel-shaped, at least in its bottom portion.

By mounting a stirrer in the container 1 for the disinfecting agent right above the dosimeter 2, it is possible to secure a definitely uniform supply of the disinfecting agent to the dosimeter and, thus, to the mixing chamber 3. The function of the stirrer is to keep the powder material in a fluffy state, on one hand, and to feed the powder f rther into the dosimeter 2, on the other hand.

Practical experiments have proved that a suitable embodiment of the mixing chamber 3 is a substan¬ tially vertical ube, to whose bottom end the blower 4 is connected and to whose top end the connecting pipes 5 are connected, preferably by means of a branch piece 9.

In order that each potato could be treated even more uniformly, the connecting pipes 5 may be pro¬ vided with a branch piece 10 before the corresponding planting tube 7 , which said branch piece divides the powder-air flow in two component flows, which flow into the planting tube 7 from opposite sides . This arrangement is also justified thereby that, usually,

two potato-feed bands or chains 8 placed side by side are arranged in the same planting tube 7, whereat each of the component flows is directed at a band or chain 8 of its own. The advantage of having two chains 8 per planting tube 7 lies, as is well known, therein that, in such a case, the speed of the chains 8 has to be only about one half of the speed that would be required by the running speed of the potato planting machine 6 if only one chain 8 per planting tube 7 were used.