The present invention concerns a feeder apparatus for timber harvesters in which apparatus the infeed movement, parallel to the log, is generated with a rotating, preferably three strand roller chain. One or more feeder apparatuses can be employed in one timber harvester. Attached to the side plates of the roller links of the roller chain are members such as spikes which grab the log which is being moved; thus, the roller chain inclusive of its grabbing members is below referred to as a track.

In tracks, the loading force between the track and its bed presents a problem. Further, it is difficult to support a track in the area where the driving and turning wheels meet the bed. In this area, the cogs of the driving and turning wheels require some space, meaning that the bed cannot extend seamlessly into the turning - and driving wheels. Further, in conventional tracks, the track elements tend to move to an upright position, as the distance to the grabbing spike, placed perpendicularly to the direction the track is pulled, on top of the pulling link and the track element, is considerable as compared to the space between the joints of the track element. When the chain is pulled, a moment is created which tends to force the front edge of the track element up and the rear section of the element, down. Simultaneously, the loading force to which the track and the bed are subjected becomes localized. In a feeder ^" apparatus in accordance with the present invention, the above problems associated with tracks have been considerably eliminated and thus a light-weight, compact feeder apparatus has been arrived at.

The characteristics of the present invention are listed in the enclosed Claims. A feeder apparatus in accordance with the invention, inclusive of its track, is especially developed for loading processors and harvesters. The low weight and compactness of the feeder apparatus were arrived at by utilizing the roller links normally found in the roller chains employed in tracks. In the track, the roller

links have been positioned in three interlaced strands such that adjacent roller links do not have the same position and that there are no side plates between the roller links as is the case in conventional multiple strand roller chains. The track itself is made up of parts available in conventionally constructed roller chains. Preferably, the track elements constitute the roller links of the roller chain. Thus, the price of the track is economical and, empoloying various structural solutions, it is easy to weld grabbing spikes on the roller links. By placing the roller links of the track such that adjacent roller links do not have the same position, many significant advantages are secured as compared for example to a track made of a multiple strand roller chain. First, the number of adjacent strands should ideally be three, and, between the roller links, there are no side plates belonging to the pin links as is the case in multiple strand chains. Thus, the width of the roller of the roller link is increased in relation to the total width of the track; the loading capacity of the track in the lateral direction of the chain is high. Further, the adjacent roller links reach the driving and turning wheels at different times, they move in relation to one another when on the driving and turning wheels, thereby being cleansed of bark and other dirt. However, because also in this track the distance, perpendicular to the direction of pull, of the grabbing spike from the pulling joint of the roller link is long in relation to the joint spacing of the roller links, the roller links would here too tend to move to an upright position. However, as the inner links in adjacent rows are not parallel but rather arranged such that the rear joint of the preceding link is parallel with the front joint of the next and adjacent link, the rear section of the preceding link, via the pin connecting the two roller links, pushes the front section of the adjacent roller link down. Thus the upright moving tendency described above is eliminated.

In a three strand track, power transmission proper to the track can only take place by employing a cogged driving

wheel positioned on the center strand of roller links. Thus, the driving wheel is leight-weight and above all the rollers in the outer strands of roller links can be utilized to support the track against its rolling bed. This makes it possible to design the rolling bed so as to make the rolling bed surface under the outer strands of roller links constitute an arc. The outer surface of the arc corresponds to the diameter of the driving wheel minus its cogs. Thus, the chain is moved very smoothly by the driving wheel. Also, the length of the bed giving support is great.

The situation with the turning wheel is more difficult because of the tightening of the track that is done here. However, by designing the wheels to be narrower, ie. only approximately one half of the normal width, and by overlapping the corresponding rolling beds the supporting surface in the area of the turning wheel is rendered large too. On the center strand of roller links, the supporting rolling bed can be made to full width as far as the axis of the turning wheel. In the following, the invention is explained with reference to the enclosed pictures illustrating one application of the invention.

Figure 1 one feeder apparatus without a track, as seen from the log infeed side Figure 2 a cross-section of the section indicated as II-II in Figure 1 , with the driving wheel partly cut Figure 3 the roller chain, or track used in the feeding apparatus, minus the grabbing members Figure 4 a cross-section of the section indicated as IV-IV in Figure 1 , including the track

The parts of the feeder apparatus in Figure 1 are: The side plates 1 of the frame, placed on the outside of the feeder apparatus and joined by box 13. To the top of box 13 are attached the rolling beds 2 and 3. To the side plates 1 of the frame is mounted with bearings the axis 12 of the driving wheel 5, powered by the hydraulic engine 4. The two strand turning wheel 6 is also mounted with bearings on the side plates 1. However, the turning wheel 6 can be shifted

for instance with screws for tightening of the track. The turning wheel 6 can also be flush, ie. cogless.

In Figure 2, the rolling bed 2 is seen to continue, in the area of the chain's rotating movement around the turning wheel 5, such that the diameter of the surface of the bed 2 is equivalent to that of the driving wheel 5 minus its cogs. The rolling bed 3 extends from the axis of the turning wheel 6 as far as the driving wheel 5, the surfaces of the bed 3 having slanted ends. It can also be seen that the ends of beds 2 are slanted and made narrower near the turning wheel 6. Beds 2 and 3 are supported via plate 14 against box 13. Via the side plates 1 and the different holes in its, the feeder apparatus can be conveniently attached to a timber harvester. Shown as a dashed line in Figure 2 is the travel path of the track's pulling joints.

Shown in Figure 3 is a section of the track without the grabbing spikes. The track mainly consists of the roller links 7 of the roller chain. The roller links 7 are placed in three alternately aligned strands, ie. the pins 8 piercing the front section of a roller link also pierces the rear section of the adjacent roller link 7. The pins 8 are attached in pairs to the side plates 9.

Shown in Figure 4 is a cross-section of the section IV-IV indicated in Figure 1. Shown in Figure 4 is also the track, its grabbing spikes 10 and the log 11 to be fed in. It can be seen that the rolling beds 2 and 3 are conveniently flat in the area of box 13; there are no beds on the return side of the chain's movement. The side plates 1 of the frame guide the track laterally via the side plates 9 of the outer links.