GB2048032A

GB2048032A - Linkage for Agricultural Implement

Info

Publication number: GB2048032A
Application number: GB7914604A
Authority: GB
Original assignee: Hunt & Co Ltd R
Current assignee: Hunt & Co Ltd R
Priority date: 1979-04-26
Filing date: 1979-04-26
Publication date: 1980-12-10
Also published as: GB2048032B

Abstract

A linkage for attaching to a tractor a towed agricultural implement consisting of two or more sections, such as land rolls, which in the working position are arranged in a staggered array, so that the implement works a greater width than that of a single section, and which can be re-arranged into a transport position in which the overall width of the implement is reduced. The linkage consists of a transverse frame member 36 fixed to the frame 20 of the front section 10, and a draw bar 44 or 76 fitted to the or each rear section 12 or 14 and connected at its forward end to the transverse frame member 36, e.g. through a sliding carrier 46, so as to be movable along the transverse frame member 36 between positions corresponding to the working and transport positions of the implement. The connections are such that each section can be moved from one position to the other, after releasing a locking device on the draw bar, by manoeuvring the tractor, thus avoiding the necessity to manhandle the sections. In a preferred embodiment, the transverse frame member 36 has at least one retractable portion 40 which can be retracted to reduce the width of the frame member in the transport position. <IMAGE>

Description

SPECIFICATION Linkage for Agricultural Implement This invention relates to linkages for connecting a towed agricultural implement to a tractor.

The invention is particularly concerned with linkages for towed implements consisting of two or more sections which in the working position are arranged in a staggered array, so that the implement works a greater width than that of a single section, and which can be rearranged into a transport position in which the overall width of the implement is reduced, to enable it to be towed along roads or through narrow openings such as gateways or over bridges. For example, in the case of a land roll consisting of three separate sections or rolls, it is usual for the sections to be arranged in the working position with one section towed directly behind the tractor and the other two sections connected to opposite ends of the frame of the front section and towed by the front section.To move them into the transport position, the two rear sections are unhitched from the front section, the first rear section being re-hitched to the centre of the frame of the front section and the second rear section hitched to the centre of the frame of the first rear section, so that the three sections can be towed one behind the other.

Since the two rear sections have to be manipulated into the new position, the change from the working position to the transport position, and vice versa, is time-consuming and, if heavy land rolls are involved, may require more than one man.

It is the object of this invention to provide an improved linkage for connecting a multiplesection agricultural implement to a tractor, which facilitates the change between the working and transport positions.

The invention consists in a linkage for attaching to a tractor an agricultural implement consisting of at least two sections so that in the working position the sections are arranged in a staggered array with the foremost section connected to the tractor and the or each rear section to the rear of and transversely displaced with respect to the foremost section whilst in the transport position the or each rear section is positioned behind the foremost section, comprising a transverse frame member fixed to the frame of the foremost section, a draw bar fitted to the or each rear section and connected at its forward end to the transverse frame member of the front section so as to be movable along the transverse frame member between positions corresponding to the working and transport positions of the implement so that, in use, the forward end of the draw bar can be moved from one position to the other by movement of the tractor without disconnecting the draw bar from the transverse frame member, and means for releasably locking the draw bar in each of the two positions.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic plan view of a triple-section land roll in accordance with the invention, with the implement in the working position, Figure 2 is a diagrammatic plan view of the implement in the transport position, Figure 3 is a diagrammatic side elevation of the implement in the working position, Figure 4 is a plan view, on a larger scale, of'the front section of the implement, Figure 5 is a plan view, on a still larger scale, of a detail showing the connection of a drawbar to the front section, Figure 6 is a section on line VI--VI of Figure 5, and Figures 7 and 8 are diagrammatic plan views of a double-section land roll in accordance with the invention, showing the implement in its working and transport positions.

Referring to Figures 1 to 6, the land roll has a front section 10 and two rear sections 12 and 14.

The front section 10 has a generally rectangular frame 20. A drawbar 22 is welded to the centre of the front member 24 of the frame and is braced by two bracing members 26. The draw-bar 22 is adapted at its outer end for connection in conventional manner-to a tractor. The side members 28 of the frame 22 carry suitable bearings between which a land roll 30 is supported.

Welded to the rear member 32 of the frame 20, through spacers 34, is a horizontal rail 36 in the form of an inverted channel-section. The rail 36 extends to points spaced somewhat from the ends of the frame 20. At each end of the frame, pivoted to the rear frame member 32 by a pin 38, is an arm 40, of the same channel-section as rail 36. Each arm 40 can take up a horizontal position (shown in Figure 4) in which it is aligned with and in effect forms an extension of the rail 36. Each arm 40 is prevented from moving below the horizontal position by engagement of the arm with a stop 42 fixed to the rear frame member 32, and can be pivoted upwards and inwards to a retracted position in which it rests against the stop 42. Each arm 40 is braced by a strut 44 fixed at its rear end to the arm 40 and pivoted at its forward end to a bracket 46 at the front of the frame 20.

The rear land roll section 12 has a frame 42, which may be similar to that of the front section 12, except that, as shown, it is not necessary to provide a rear frame member. A draw bar 44 is fixed to the frame 42. Welded to the forward end of the draw bar is a carrier 46, comprising a member 48 having a vertical portion 50 welded to the draw bar 44 and a horizontal portion 52 extending beneath the rail 36 of the front section frame 20, and a horizontal locking plate 54 fixed to member 48 by means of a bolt 56 and spacer collar 58. The locking plate projects above and rests on the rail 36, and engages a heel 60 fixed to the vertical portion 50 of member 46 to resist the turning moment exerted on the plate through its engagement with the rail 36.The member 48 carries at its forward end a roller 62 mounted on a vertical spindle 64, the roller projecting into the channel section rail 36, so that the carrier can move along the rail 36. Means are provided for locking the carrier in two positions on the rail, as described below. These means could take the form of a removable pin extending through aligned bores in the locking plate 54, rail 36 and member 48.

The other rear land roll section 14 has a frame 74 similar to that of the rear section 12. However, the draw bar 76 fixed to frame 74 is longer than the draw bar 44 of rear section 12, so that the rear sections 14 can take up a position directly behind the rear section 12, in the transport position shown in Figure 2. To enable the draw bOr 76 to clear the rear section 12 in the transport position, it is formed (see Figure 3) with an upwardly inclined rear section 78, a horizontal intermediate section 80, and a forward vertical section 82. To the vertical section 82 is fixed a carrier 46 identical to that fixed to draw bar 44 of rear section 12, the vertical section being fixed to the portion 50 of the carrier as illustrated in broken lines in Figure 6.

In the working position, as shown in Figure 1, the arms 40 are in the extended position, and the carriers 46 of the two rear sections 12 and 14 are positioned at opposite ends of the arms 40, so that the rear sections are laterally staggered relative to the front section 1 0. In the transport position, as shown in Figure 2, the two carriers 46 are close to the centre of the rail 36, so that the two rear units are practically in line behind one another and behind the front section 10, and the arms 40 are in the retracted position. To change from the working position to the transport position, the locking pins holding the carrier 46 of one rear section in place is released, and the tractor towing the implement is manoeuvred so that the front section 10 is turned in such a way as to cause the carrier to slide along the arm 40 and rail 36 to its central position.For example, if the carrier of the right-hand rear section 12 is released first, the tractor is driven to the left so that the frame of the front section 12 is turned anticlockwise, as seen in plan, causing the carrier 46 to move along the arm 40 and rail 36 until it engages a stop 84 (Figure 4) on rail 36. The carrier is then locked in that position, and the arm 40 pivoted to its retracted position. The operation is then repeated for the other frame section 14, the tractor in that case being driven to the right.

To change from the transport to the working position the sequence-of operations is reversed.

Stops are positioned at the outer ends of the arms 40 to limit the outward movement of each carrier 46 as the tractor is manoeuvred to cause the carrier to slide from its central to its outer position.

The described linkage thus enables the implement to be changed between the transport and working positions without any need to unhitch the rear sections from the front section or to manhandle the sections into position.

Figures 7 and 8 illustrate a modification of the described embodiment in which only two land roll sections are employed. The rear section 121 is connected to the frame 120 of the front section 110 in the same way as the section 12 of the embodiment of Figures 1 to 6, the draw bar 144 of the rear section 121 having a carrier 146 movable along a rail 136 and a retractable arm 140 attached to the frame 120 of the front section 11 0. To enable the two sections to take up positions which are laterally symmetrical with respect to the centre line of the tractor, in the working position, the draw bar 122 of the front section is pivoted at 123 to the frame 120 of the front section and is movable between a working position (Figure 7) in which the hitch point 125 is on the centre line of the implement and a transport position (Figure 8) in which the hitch point 125 is on the aligned centre lines of the two sections 110 and 112. The draw bar is held in each position by means of a strut 127 pivoted at its outer end to the draw bar and slidably connected at its rear end to the front member 1 24 of frame 120 so that it can be clamped to the frame member 124 in each of the two positions shown.

It will be appreciated that many modifications could be made in the described embodiments. For example, the roller 62 on each carrier 46 could be replaced by a solid pin slidable in the channelsection 36. The rail 36 and arms 40 could take different forms, and the arms could, for instance, be slidable between the retracted and extended positions instead of pivotable. It will also be appreciated that the invention could be applied to other agricultural implements consisting of two or more sections, or to linkages for trailing a gang of separate implements behind a tractor. The linkage could be extended to cope with more than three sections or implements.

Claims

1. A linkage for attaching to a tractor an agricultural implement consisting of at least two sections so that in the working position the sections are arranged in a staggered array with the foremost section connected to the tractor and the or each rear section to the rear of and transversely displaced with respect to the foremost section whilst in the transport position the or each rear section is positioned behind the foremost section, comprising a transverse frame member fixed to the frame of the foremost section, a draw bar fitted to the or each rear section and connected at its forward end to the transverse frame member of the front section so as to be movable along the transverse frame member between positions corresponding to the working and transport positions of the implement so that, in use, the forward end of the draw bar can be moved from one position to the other by movement of the tractor without disconnecting the draw bar from the transverse frame member, and means for releasably locking the draw bar in each of the two positions.

2 A linkage as claimed in claim 1, in which the transverse frame member includes at least one retractable portion movable between a retracted position and a working position in which it projects transversely from the frame of the foremost section.

3. A linkage as claimed in claim 2, in which the or each retractable portion is pivotally mounted on the frame of the foremost section.

4. A linkage as claimed in any preceding claim, and adapted for use with an implement having two rear sections, in which the draw bar connected to a first one of the rear sections is shorter than that connected to the other second rear section, and the positions of the draw bars corresponding to the transport position of the implement are such that the second rear section is, in the transport position, disposed directly behind the first rear section.

5. A linkage as claimed in claim 4, in which the draw bar for the second rear section is shaped so as to extent over the first rear section in the transport position.

6. A linkage as claimed in any one of ciaims 1 to 3, and adapted for use with an implement having a single rear section, in which there is provided a draw bar for the foremost frame section movable between a transport position in which a hitch point at the forward end of the draw bar is on the aligned centre lines of the two sections and a working position in which the hitch point is transversely displaced from the centre line of the foremost section so that in the working position the two sections are transversely displaced in opposite directions from the centre line of the implement whilst the hitch point remains on that centre line.

7. A linkage for connecting a towed agricultural implement to a tractor, constructed, arranged and adapted to operate substantially as described with reference to, and as shown in, Figures 1 to 6 or Figures 7 and 8 of the accompanying drawings.