EP1467612A1

EP1467612A1 - Device for movement in steps of a manure scraper

Info

Publication number: EP1467612A1
Application number: EP02793653A
Authority: EP
Inventors: Thord Siljefelt
Original assignee: Sveaverken Odin AB
Current assignee: Sveaverken Odin AB
Priority date: 2001-12-17
Filing date: 2002-12-16
Publication date: 2004-10-20
Also published as: SE521012C2; SE0104253L; SE0104253D0; AU2002359141A1; WO2003056906A1

Abstract

This invention relates to a device for movement in steps of a manure scraper, the device comprising a carriage (1) that supports one or more floor scrapers which extends/extend out from the sides of the carriage (1), a drive rail (2) along which the carriage (1) is caused to move and which is connected to the carriage (1) by means of a carriage-mounted pawl (3) which is adapted for actuation by dogging means (6) disposed on the drive rail (2), whereby the pawl (3) is carried by a shaft (4) that includes shaft pivots (4.1) which are each disposed in a respective vertically extending elongate opening (5). The respective opening (5) to includes for the respective shaft pivot (4.1) abutment surfaces (5.1) that extend in two planes (P) which slope downwards and outwards at an angle (A) from each side of the upper portion of the respective opening (5). The connecting line between the point of contact of the pawl (3) on the drive rail (2) and the points of contact on the abutment surfaces (5.1) is directed towards the respective abutment surface (5.1) in a sector that lies above a normal (N) to the plane (P) through the abutment surface (5.1) at the respective contact point on the respective abutment surface (5.1).

Description

DEVICE FOR MOVEMENT IN STEPS OF A MANURE SCRAPER

TECHNICAL FIELD

The present invention relates to a device for movement in steps of a manure scraper in a manure passageway. The device includes a carriage which supports one or more floor scrapers that extend out from the sides of the carriage, and a drive rail along which the carriage is caused to move in contact with the floor in the manure passageway. The carriage has a movement direction switching means which is aimed at solving the problem with the scraper running into animals or other obstacles that are present in the manure passageway.

PRIOR ART

A device of the kind defined in the preamble is known from the European patent specification EP 0 770 325, which describes a complete plant for dischar- ging manure from manure passageways in a cowshed. The known device includes a carriage that supports one or more floor scrapers, which extend out from the sides of the carriage, a drive rail along which the carriage is caused to move and which is connected to the carriage by means of a pawl mounted on the carriage and actuated by dogging means on the drive rail. The pawl is supported by a shaft which includes shaft pivots, each of which is disposed in a respective vertically extending elongate opening, and at that part located above the shaft the pawl supports against a stop pin. When the device runs onto an obstacle, the carriage is lifted and the shaft slides down with the shaft pivots moving in respective elongate openings so as to release the pawl from the stop pin and therewith allow the pawl to swing over to the opposite side of the shaft.

The object of the present invention is to provide a corresponding but simpler switching means.

SUMMARY OF THE INVENTION The inventive device is intended for the movement in steps of a manure scraper and includes a carriage that supports one or more floor scrapers which extends/extend out from the sides of the carriage, a drive rail along which the carriage is caused to move and which is connected to the carriage by means of a carriage-mounted pawl which is adapted for actuation by dogging means disposed on the drive rail. The pawl is carried by a shaft that includes shaft pivots which are each disposed in a respective vertically disposed elongate opening. The respective opening includes abutment surfaces for the respective shaft pivot which surfaces extend in two planes which slope downwards and outwards at an angle from each side of the upper narrow portion of the opening. In the case of one suitable embodiment, the angle of inclination to the vertical may be 20°, although it may be greater or smaller than 20°.The angle of inclination is determined by the relationship between the length of the pawl between the dogging point on the drive rail and the point of contact of respective abutment surface in the respective opening and the vertical distance between the drive rail and respective contact point on the respective abutment surface. It will be understood that the abutment surface may very short and merge with the upper part of the opening via different curve forms. Thus, the abutment surface may consist of a tangent to a curve in the opening. The opening may, for example, have the form of an inverted "keyhole" or have a triangular shape.

In normal operation, the drive rail exerts, on the one hand, a horizontal force on the pawl, and, on the other hand, an upwardly directed vertical force and a resultant force, said forces being transferred to the abutment surfaces via the shaft pivots. The contact points of the pawl on the drive rail and the carriage respectively can thus be considered as pivot points. The resultant force is therewith directed against the respective abutment surface in a sector that lies above the normal to the plane through the abutment surface at the contact point of respective shaft pivot, which means that the shaft pivots are pressed against the lower part of the opening. In this stable operating state, the weight of the carriage with associated floor scrapers is sufficient to prevent the carriage from being lifted up from the drive rail. The carriage with the scrapers will in that way move along the drive rail at a uniform speed.

In the event of the movement of the carriage being impeded by an obstacle the force on the pawl will increase whereby the carriage will tend to be lifted from the floor . When the carriage is lifted to a given point, the resultant force will be directed in a sector that lies beneath the aforesaid normal to the plane through the abutment surfaces, whereby the shaft pivots will slide up in the respective openings to a height such as to cause the pawl to be moved to the opposite side of the shaft by the forward movement of the drive rail, and there once again engage with dogging means upon return movement of the drive rail. The carriage it thereby caused to move away from the obstacle concerned.

The invention is not limited to the discharge of manure from a manure passageway, but may also be applied to other types of scrapers and with materials other than manure. It is also within the scape of the invention to use it for other feeding arrangements in which a drive rail is used for carriage movement along a drive rail.

Further details and characteristic features of the invention will be apparent from the following description of the accompanying drawings and from the claims.

LIST OF DRAWINGS

The invention is described below as an exemplifying embodiment of a manure discharge device and in connection with the accompanying drawings.

Figure 1 shows a carriage and parts of a drive rail included in a device according to the invention, the carriage being partially cut and without the arms belonging to the actual floor scraper for manure.

Figure 2 shows the drive rail and the carriage of the fig. 1 device from above.

Figure 3 shows an enlarged section of the carriage and the drive rail of fig. 1 .

Figure 4 shows the end of the drive rail included in the device according to the invention.

DESCRIPTION OF THE DRAWINGS The carriage shown in figures 1 and 2 is intended to support floor scrapers on each side of the carriage 1 , principally in a manner known from patent specification EP 0 770 325 and for that reason the scrapers have not been included in the figures. The carriage 1 has a cross-section in the form of an inverted U whose internal width corresponds to the width of a drive rail 2 which is intended to move linearly in steps, forwards and backwards along the floor of a manure passageway, with the carriage 1 straddling the drive rail 2. The drive rail 2 per se has a U- shaped cross section and is placed with the legs of the U in abutment with the floor and is moved with the aid of an hydraulic piston-cylinder device which is not shown in the figures. The carriage 1 is provided with a pawl 3 mounted on a horizontal shaft 4 which includes shaft pivots 4.1 extending from the ends of the shaft 4, through openings 5 on each long side of the carriage 1. The carriage 1 is moved in one of the directions by bringing the pawl into engagement stepwise with rectangular dogging holes 6 disposed on the upper side of the drive rail 2 along its length. The respective opening 5 for the respective shaft pivot 4.1 has an elongate shape as seen vertically and include abutment surfaces 5.1 extending in a plane P that slopes downwards and outwards at an angle A to the vertical from the upper part of the opening 5 , there having a width which only slightly exceeds the diameter of the respective shaft pivot 4.1. In the case of the illustrated example, the angle of inclination A is 20°, although the angle may be greater or larger than 20°. In normal operation, the drive rail 2 exerts on the pawl 3, on the one hand a horizontal force F1 and, on the other hand, an upwardly directed vertical force F2 and a resultant force F3, said forces being transferred to the abutment surfaces 5.1 via the shaft pivots 4.1. The contact points of the pawl 3 on the drive rail 2 and the carriage 1 respectively can thus be considered as hinges. The resulting force F3 is thereby directed against the respective abutment surface 5.1 in a sector that lies above the normal N to the plane P through the abutment surface 5.1 at the respective contact point, which means that the shaft pivots 4.1 are pressed against the lower part of the opening 5. In this stable operating state of the device, the combined weight of the carriage 1 with the associated floor scrapers is sufficient to prevent the carriage 1 from being lifted up from the drive rail 2. The carriage 1 and its scrapers will thereby move along the drive rail 2 at a uniform speed. In the case of the illustrated embodiment, the length of the pawl 3 between the dogging point on the drive rail 2 and the contact point on the respective abutment surface 5.1 in the respective opening 5 corresponds to about three times the vertical distance between the drive rail 2 and the respective contact point on the respective abutment surface 5.1. The shorter the pawl 3 length, the greater the intrinsic weight of the carriage 1 with its associated scrapers required to prevent lifting of the carriage at excessively low resistance to the scrapers. A practical lower limit is two times said distance.

In the event of movement of the carriage 1 being impeded by an obstacle, for instance a cow lying in the passageway, the force on the pawl 3 will increase and the carriage 1 will tend to lift away from the floor as a result of the lever arm constituted by the pawl 3, i.e. the moment arm between the horizontal force F1 on the drive rail 2 and the horizontal counter forces on the points of contact of the shaft pivots 4.1. When the carriage 1 is lifted to a given point, the resulting force F3 will be directed in a sector that lies beneath the normal N to the plane P through the abutment surfaces 5, whereby the shaft pivots 4.1 slide up in the upper narrower part of respective openings 5 to a height such as to cause the pawl 3 to be moved to the opposite side of the shaft 4 by the forward movement of the drive rail 2, and there re-engage with the dogging holes 6 upon return movement of the drive rail 2. The carriage 1 is thereby caused to move away from the obstacle concerned. The height of the drive rail 2 shall be sufficient to prevent the long sides of the carriage 1 from being lifted above the upper side of the drive rail 2, so that the carriage will still be guided laterally by the drive rail 2 even when in a raised position.

When the carriage 1 reaches the end of the drive rail 2, the pawl 3 switches automatically to an opposite position and feeds the carriage 1 in the reverse direction. This can also be obtained by providing a longer switching hole 6.1 at one or both ends of the rail 2.

Claims

1. A device for movement in steps of a manure scraper, the device comprising a carriage (1) that supports one or more floor scrapers which extends/extend out from the sides of the carriage (1), a drive rail (2) along which the carriage (1) is caused to move and which is connected to the carriage (1) by means of a carriage-mounted pawl (3) which is adapted for actuation by dogging means (6) disposed on the drive rail (2), whereby the pawl (3) is carried by a shaft (4) that includes shaft pivots (4.1) which are each disposed in a respective vertically dis- posed elongate opening (5), characterized in that the respective opening (5) includes for the respective shaft pivot (4.1) abutment surfaces (5.1) that extend in two planes (P) which slope downwards and outwards at an angle (A) from each side of the upper portion of the opening (5); and that the connecting line between the point of contact of the pawl (3) on the drive rail (2) and the points of contact on the abutment surfaces (5.1) is directed towards the respective abutment surface (5.1) in a sector that lies above a normal (N) to the plane (P) through the abutment surface (5.1) at the respective contact point on the respective abutment surface (5.1), causing the shaft pivots (4.1) to be urged against the lower part of the opening (5) by the force exerted by the drive rail (2).

2. A device according to claim 1 , characterized in that the pawl (3) length between the dogging location on the drive rail (2) and the contact point on the respective abutment surface (5.1) in the respective opening (5) corresponds at least to two times the vertical distance between the drive rail (2) and the respective contact point on the respective abutment surface (5.1).

3. A device according to claim 1 , characterized in that the pawl (3) length between the dogging location on the drive rail (2) and the contact point on the respective abutment surface (5.1) in the respective opening (5) corresponds at least to three times the vertical distance between the drive rail (2) and the respective contact point on the respective abutment surface (5.1).

4. A device according to any one of claims 1-3, characterized in that the dogging means (6) on the drive rail (2) are constituted by rectangular holes.

5. A device according to any one of claims 1-4, characterized in that a switching hole (6.1) is arranged at at least one end of the drive rail (2).