The present invention relates to a forage harvester having a chopper assembly and a delivery arrangement that are connected to each other by a channel that is provided with a cutout into which a crop processing arrangement or a conveyor arrangement can be selectively inserted.
A Claas Company advertising brochure, bearing the designation 8/95 (M+E) dt. 150/190.432.7, discloses a forage harvester equipped with a chopper assembly including a chopper drum that chops crop such as corn, grass, sorghum and the like and directs it through a channel to a blower that delivers the chopped crop to a delivery arrangement from where it flows to an accompanying vehicle. In addition to the blower, the channel contains a crop processing arrangement that consists of two rolls that rotate in opposite directions about parallel, with the crop being fed between and crushed by the rolls. The crop processing arrangement consists of a single unit or module and as such can selectively be either installed or removed by sliding the unit horizontally through a cutout in the channel, installation usually being done when corn or sorghum is being harvested and removal usually being done when grass is being harvested for silage.
U.S. Pat. No. 4,678,129, granted to Dallinger on 7 Jul., 1987 also discloses a crop processing arrangement with two rolls rotating in opposite directions that are installed in a channel. Here the lower roll can be pivoted out of the channel on pivot arms and replaced by a roll carrying paddles. The roll with paddles interacts with the remaining roll that carries teeth on its outer surface in order to convey the crop to a blower. In this way jamming should be avoided when the crop processing arrangement is employed in the grass harvest. A comparable solution is also provided according to FR-B1-25 39 950, published 3 Aug. 1984.
According to U.S. Pat. No. 4,696,432, granted to Russ et al. on 29 Sep. 1987, either a crop processing arrangement or a conveyor arrangement can be selectively installed in the channel between the chopper assembly and the delivery arrangement. However, in each case, the channel is specifically configured to accommodate the particular arrangement used and accordingly, a single channel configuration is not compatible with both arrangements.
The problem underlying the invention is seen in the fact that the fine and sharp-edged teeth on the circumferential surface of the rolls employed for the processing do not have a sufficiently non-skid surface for the conveying of grass and become dull under constant operation on grass. On the other hand, removal of the crop processing arrangement can lead to the condition that the crop is not accelerated sufficiently.