GB2095085A - Potato harvester - Google Patents

Abstract

A potato harvester is provided with plowshare (1) and a conveying and sieving belt (5) extending transversely of the plowshare (1) and transversely of the furrow direction. The lower span or rim (6) of the belt (5) is positioned in such manner immediately adjacent the back of the plowshare (1) that the excavated mass is led directly into the upper surface of the lower span or rim (6) of the belt (5). The lower span (6) of the belt (5) extends from the share (1) in a transverse direction to form a transportation/sieving expanse and is reversed to form the upper span (7) by means of a narrow reversal wheel (13) positioned in the central region of the belt width. <IMAGE>

Description

SPECIFICATION Potato harvester This invention relates to an improved potato harvester having a plowshare and a conveyor/sieving belt extending transversely of the plowshare and transversely of the furrow direction, which receives the mass excavated by the plowshare.

Transferring the excavated mass from the plowshare to the belt is a problem. The plowshare has to dig down rather deeply in the potato furrow, while at the same time the lower idler pulleys for the belt must be spaced a certain minimum distance above the ground. As a result of these conflicting requirements, there will be a gap between the share and the belt. Heretofore, attempts have been made to bridge this space by means of a guide plate which forms an extension of the belt down to the share, or by providing a wheel which throws up the mass that has been excavated onto the belt, or, e.g., by utilizing as described in Norwegian Patent No. 100,449.

The present invention aims to enable a direct transfer of the excavated material from the plowshare to the transversely-extending belt, without any intermediate transfer member. In accordance with the invention, it is proposed that the inside surface of the lower span of the belt be utilized for transporting and sieving the mass. The belt can thereby be brought farther down toward the ground and pass beneath the level of the rear edge of the share, so that the mass can be introduced onto the lower span or rim of the belt.

Thus, a section of the lower span or rim of the belt will pass beneath earth level, and it is the lower span of the belt which constitutes the conveyor portion of the belt.

From German utility model (DE-B) 1,482,050, it is known to utilize a conveyor/sieving belt travelling transversely of the plowshare which receives the mass excavated by the share on the inside surface of the lower span of the belt, but transfer of the mass occurs via a longitudinal conveyor belt arranged between the plowshare and the transverse belt. This additional conveyor belt makes the potato digger more compicated and expensive, and increases its weight.

According to the present invention there is provided a potato harvester comprising a plowshare or excavator member and a conveyor/sieving belt extending transversely of the plowshare for receiving the excavated mass from the share on the upper surface of the lower span or rim of the belt, a section of the lower span or rim of the transverse belt being disposed immediately adjacent the back of the share so that the excavated mass is led directly onto the upper surface of the lower span or rim of the belt.

By allowing the belt quite simply to pass behind the plowshare, as stated above, one obtains several advantages. Firstly, the entry of the mass from the share onto the belt is uncomplicated, which permits higher driving speeds without running the risk of blockage, as is often the case with other belt-entry systems. Secondly, one avoids the drawback that parts of the sieved mass, such as stones, clods of earth and plant remains, can fall down onto the return side of the belt, as is the case with the traditional double belts in which the mass is guided onto the top side of the belt, i.e., on the upper span of the belt. It is a common problem today that plant remains, rocks, etc., collect at the point where the belt bends back and cause blockages. By using the upper surface of the lower span or rim of the belt, such problems are avoided entirely.Compared with the known arrangements especially mentioned above, one obtains with the invention a simpler, lighterweight and less expensive construction.

Preferably, the plowshare and belt are arranged in such relationship that an edge region of the said belt section extends in beneath the share, so that one obtains a slight overlapping in this area. This naturally facilitates the transfer of the mass from the plowshare to the belt.

The mass which is transferred to the lower span or rim of the belt, consisting of a mixture of plant remains, stones, potatoes and soil, is subjected to a sieving effect as it is being transported on the lower span or rim of the belt, and at the end of the lower span or rim of the belt it is guided onto a conveyor means which carries the mass, preferably mainly potatoes, to a collection bin, or preferably to a cleaning belt, as known per se. To increase the likelihood that soil, rocks and the like will be removed from the lower span or rim of the belt before the belt is bent back on itself to become the upper span, the belt is preferably reversed about a narrow reversal wheel positioned in the central region of the belt width.In this way, ample space is thereby provided on both sides of the wheel for soil and stones to be shaken loose and fall to the ground in this critical region of the belt path.

In the vicinity of said reversal wheel, it is advantageous to pass the belt over a bending pulley which determines the arc of contact of the belt on the wheel; this bending pulley is preferably driven, thus constituting the drive means for the belt.

The upper span or rim of the belt is led back in the opposite direction (relative to the direction of transport on its lower span or rim) at a suitable, higher level above the ground, and is then turned to pass down and travel past the plowshare as the lower span once again.

An embodiment of the invention will now be described, by way of an example, with reference to the accompanying drawings, in which: Figure 1 is a schematic representation of a potato harvester in accordance with the invention, in front view, and Figure 2 shows the potato harvester in schematic plan view, with only those structural members which are necessary for an understanding of the invention being shown.

The Figures show a plowshare excavator member, designated by the numeral 1. The plowshare 1 has a downwardly-curved configuration, as known per se, and cuts down into the ground 1 8 and lifts up the potato furrow.

The plowshare 1 co-operates with diagonallydisposed guide discs 3 and 4. At the forward edge of the plowshare 1, a depth wheel 2 is also provided. The depth wheel 2 serves to adjust the depth of the cut and also has a relatively sharp edge for cutting off the potato plant tops, in a manner known per se.

The mass in the excavated furrow is guided as indicated by the arrows onto a transversely extending conveyor and sieving belt 5, whose lower span or rim is designated 6 and its upper span or rim 7. The belt 5, as may be seen in Figure 2, is constructed in a manner known per se as a rib belt. The belt 5 passes around and is supported by idler and support pulleys 8, 9, 10 and 11.

The lower span or rim 6, over an expanse extending forward to a drive pulley 12, forms a conveying and sieving member, the drive pulley 12 operates simultaneously as a bending or guide pulley for the belt 5 and guides the belt 5 onto a return wheel 13. The return wheel 1 3 is formed as a narrow wheel, as may be seen in Figure 2, and is positioned approximately in the middle of the belt width.

At the end section of the lower span or rim 6, a guide plate 14 is provided which guides the remaining mass, consisting mainly of potatoes and larger stones, onto a conveying/elevating belt 15, which is indicated by dashed lines in Figure 1 and which carries the mass further upwardly and in the opposite direction, for delivery to a sorting belt (not illustrated) which travels generally horizontally and in parallel with the two belts 5 and 1 5. The belt 1 5, for the sake of simplicity, is not shown in Figure 2.

The mass which travels further past the driver/guide pulley 12 will fall down through the spaces formed on both sides of the narrow return wheel 13 and will be discharged on both sides of the belt, as indicated by arrows in Figures 1 and 2.

In the region at the rear of the plowshare 1 , the lower span or rim 6 of the belt 5 passes beneath the share 1 with a slight overlap below the rear edge of the share 1, to provide a desirable overlapping in this region. Rearwardly of the share 1, on the other longitudinal side of the conveying/sieving belt 5 (the far edge, as seen in the drawings), a back plate 1 6 is provded, as indicated by the heavy, solid line in Figure 2, which guides the mass which has been excavated and transferred onto the belt 5 in the direction of transportation, or towards the right as viewed in the figures. As mentioned above, Figures 1 and 2 show only those components which are necessary for understanding the invention, it being assumed that a person skilled in the art will be fully cognizant of the ways in which the machine frame may be formed for supporting the respective pulleys and wheel, and how drive mechanisms, etc. may be formed. Instead of the illustrated guide discs 3, 4, one could of course utilize other members for guiding the mass, or optionally employ a different plowshare configuration. The essential feature of the invention is that the mass which is excavated by the plowshare 1 is transferred directly onto the upper surface of the lower span or rim 6 of the belt 5, which carries the mass further while at the same time providing a sieving effect.

Claims (6)

1. A potato harvester comprising a plowshare or excavator member and a conveyor/sieving belt extending transversely of the plowshare for receiving the excavated mass from the share on the upper surface of the lower span or rim of the belt, a section of the lower span or rim of the transverse belt being disposed immediately adjacent the back of the share so that the excavated mass is led directly onto the upper surface of the lower span or rim of the belt.

2. A potato harvester as claimed in claim 1, in which an edge region of said belt section extends inwardly underneath the share.

3. A potato harvester as claimed in claim 1 or claim 2, in which the lower span or rim of the belt extends from the plowshare in said transverse direction to form a transportation and sieving expanse and is reversed in direction to form the upper span by means of a reversal wheel positioned in the central region of the belt width.

4. A potato harvester as claimed in claim 3, in which the lower span or rim of the belt, at said reversal wheel, passes over a bending pulley which determines the arc of contact of the belt on the reversal wheel.

5. A potato harvester as claimed in claim 4, in which the bending pulley is driven.

6. A potato harvester substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.