The present invention relates to a scraper conveyor of the type comprising a conveyor chain or wire, which is provided with a plurality of transverse scraper members and passes along a closed path at least partly defined by stationary conveyor channel or tube means extending from a material inlet station and past one or more receiver stations, in which the material is dispensable through outlet openings in said channel or tube means, the conveyor chain or wire being driven by means of a driving wheel engaging with said transverse scraper members. Such conveyors are widely used e.g. as feedstuff conveyors for distributing feedstuff to a plurality of feeding places in different types of animal houses.

The transverse scraper members are normally made as circular discs which are centrally rigidly associated with respective chain links or with the wire with, constant mutual spacing e.g. 5 cm, and the driving wheel is a sprocket having radial teeth or projections drivingly cooperating with the rear sides of the scraper members as the conveyor chain or wire passes about a portion of the sprocket circumference.

In the following reference will be made solely to circular scraper discs as provided on a wire, concentric¬ ally therewith, but it will be appreciated that the invention will even apply to conveyors in which the scraper members are mounted on a chain and/or in which the scraper members are not exactly circular or concentric¬ ally arranged on the chain or wire.

As in case of a sprocket driving a chain it is desirable that the driving sprocket cooperates with several scraper discs at the same time, i.e. the discs should be provided with a highly uniform mutual spacing on

the wire. This is in fact achievable, normally by die casting the discs directly on the wire with the required intervals therealong, whereby the discs may at the same time be stabilized against tilting on the wire, viz. by being shaped with a central hub portion of increased axial length.

In practice, however, the driving of the conveyor wire causes considerable problems with respect to the ^■ uniform distribution of the driving force between the various scraper discs as being present on the sprocket at any time. Even small differences in the unavoidable wear on the rear sides of the discs as cooperating with the sprocket may change the effective pitch of the discs, and so may feedstuff deposits on the rear sides. A special problem resides in the joining of the opposed wire ends for the forming of a closed wire loop or endless conveyor wire, because it is hereby rather critical that the wire ends be joined so as to provide for the required exact standard spacing between the discs at both sides of the joint.

It is the purpose of the invention to provide a conveyor of the relevant type in which the moved conveyor element is drivable without particular problems arising from a possible non-constancy of the effective pitch of the scraper members as engaged by the driving wheel of the driving station.

According to the invention the driving wheel is a circumferentially substantially smooth wheel having an outer cross sectional shape which conditions a frictional engagement between the wheel and the wheel periphery engaging portions of the outer edges of the scraper members, means being provided for tightening the moved element of the conveyor about the driving wheel sufficient¬ ly to ensure a firm frictional engagement between these parts.

Hereby the driving engagement between the driving

wheel and the conveyor wire will be entirely independent of the exact distance between the consecutive scraper discs, because the driving engagement is established between the smooth circumference of the driving wheel and the outer edge portions of the consecutive scraper discs, without specific relevance to any exact location of the rear sides of the scraper discs.

Preferably the driving wheel is profiled with a recess operable to receive approximately one half of the discs and to frictionally engage the discs adjacent almost diametrically opposite edge portions thereof, whereby the traction force on the wire is transferred from the driving wheel practically without any tilting action on the discs. In the following the invention is explained in more detail with reference to the drawing, in which:

Fig. 1 is a top view of a driving station of a conveyor according to the invention,

Fig. 2 is a side view thereof, and Fig. 3 is a partial, sectional view illustrating the driving engagement between the conveyor wire and the driving wheel.

The driving station shown comprises a housing 2 with an exterior gear motor 4 or a driving sheel 6, which engages and drives a conveyor wire provided with a series of conveyor or scraper discs 10. The wire is endless and extends through a conveyor pipe system having an upstream end 12 connected to an outlet opening from a housing portion 14, which receives from above the material to be conveyed in the system, whereby the chain 8,10 will in well known manner serve to convey the material out through the pipe system or circuit, where several outlet openings are provided bottomwise in the pipe wall. To the left in Figs. 1 and 2 is shown the downstream or return end of the conveyor pipe, which is designated 16 and is arranged tangentially to the lower portion of the driving wheel 6.

In the following the invention is explained in more detail with reference to the drawing, in which:

Fig. 1 is a top view of a driving station of a conveyor according to the invention, Fig. 2 is a side view thereof, and

Fig. 3 is a partial, sectional view illustrating the driving engagement between the conveyor wire and the driving wheel.

The driving station shown comprises a housing 2 with an exterior gear motor 4 for a driving wheel 6, which engages and drives a conveyor wixe provided with a series of conveyor or scraper discs 10. The wire is endless and extends through a conveyor pipe system having an upstream end 12 connected to an outlet opening from a housing portion 14, which receives from above the material to be conveyed in the system, whereby the chain 8,10 will in well known manner serve to convey the material out through the pipe system or circuit, where several outlet openings are provided bottomwise in the pipe wall. To the left in Figs. 1 and 2 is shown the downstream or return end of the conveyor pipe, which is designated 16 and is arranged tangentially to the lower portion of the driving wheel 6. The wire 8,10 passes about this wheel and. then about a diverter wheel 22 reversing the chain direction so as to deliver the chain to the upstream pipe end 12 along the bottom of the housing portion 14.

The slightly inclined diverter wheel 22 additionally serves as a wire stretcher, the wheel being-mounted spring biased on a stretcher block, which is adjustable along guides 24 by means of an external handle 26. A control system, which shall not be further described comprises a detector 30 for the passage of a circular row of marks 28 on the wheel 22, whereby the wheel speed is readable. As shown in Fig. 1 the driving wheel 6 has a peripheral recess 34 which is slightly deeper than the innermost half of the conveyor discs 10, while the

outermost wall portions of the recess are slightly inwardly conical and are spaced apart slightly less than the diameter of the discs 10. The wheel 6 or at least the said side walls of the recess 34 consist of a material suitable for frictional engagement with the discs 10. This design of the driving wheel 6 is shown more clearly in Fig. 3, in which, by way of example, the recess wall portions, here designated 18, are constituted by the sides of opposed V-belt members 20 rigidly mounted in annular recesses 32 in the wheel, the wheel here being made of two similar halves 36 which are bolted together.

It will be appreciated that by the driving engagement as shown in Fig. 3 the discs 10 will be safely frictionally engaged at opposite edge areas only slightly inside the diameter of the discs.' This shows the advantage that the discs will not get jammed, i.e. they will readily leave the wheel at the run off area. Furthermore the pull in the wire 8 will be transferred through the discs in a balanced manner through the opposite halves of the discs, whereby the pull will be straight, without any tilting tendency of the discs.

It will be ^' understood that the wire 8 shall have to be kept reasonably tight about the wheel 6, and that to this end it is of course not required that a wire stretcher arrangement is located within the driving station itself. The diverter wheel 22 and other diverter wheels in the system may be designed principally in the same manner as the driving wheel 6.

It should furthermore be mentioned that the driving wheel 6 may be constituted by two shell-like wheel parts being interconnected by means of transverse distance members and bolts so as to form an open wheel structure which is hereby being self-purifying.

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