RESILIENT SUPPORT BETWEEN PLOUGH FRAME AND LOWER MOLDBOARD

Hesili^t siflpport between plough frame and lower πculdboard.

FIELD OF INVENTION

The present invention relates to a soil or earth processing plough that includes a frame structure which carries plough shares and moldboards for working furrows that have been formed in the ground, and a rubber block disposed between frame and a lower mould- board.

BACKGROUND OF THE INVENTION

The working method of a plough has been developed to process furrows or ridges that contain straw and plant residues. However, successively greater demands are being placed on soil processing, where the ridges are tightly compacted and loosening of the soil required to achieve a desired result has been omitted. Constructions that include an upper and a lower moldboard that turn the ridge completely in its own furrow are known to the art. Such constructions, however, fail to fully solve the problems associated with earlier known ploughs. The "frame structure" is, in truth, two frames, which comprise the main frame, designated the upper frame, which is attached to the plough ridge that extends up to the tow bar of the tractor. The other frame is designated the lower frame and is attached to the planar part of the upper frame, said planar part also being known as the frame land side. The lower frame has two fastening points, a front point and a rear point.

It is necessary for each plough construction to take into account the large forces to which each ground- working element is subjected to, particularly when stones are present in the earth or soil being worked.

Shares, moldboards and land sides are therefore always carefully screwed securely, which is a probable reason for the poor loosening of the soil that occurs.

SUMMARY OF THE INVENTION

The present invention aims to provide a solution to the aforesaid problems and other closely associated problems, and is characterised in that there is also provided between the front attachment of the lower moldboard and the land side of the frame a pivot joint that enables vertical movement between frame and lower moldboard, i.e. vibrating of the moldboard in a vertical direction during ploughing. The front attachment for the lower moldboard is thus made pivotally movable, suitably by screwing a plate in existing holes intended for attachment of the lower moldboard to the frame.

As a result of the vibrations occurring generally vertically with respect to the lower moldboard as the ground is ploughed, the earth is loosened or broken up very effectively, i.e. the vibrations shake the ridge so as to achieve effective loosening of the earth, while achieving a strong plough construction. This vibratory movement is obtained as a supplement to the vibratory movement of the frame itself that occurs when ploughing, even with earlier known plough constructions.

DESCRIPTION OF THE DRAWINGS

The invention is illustrated in the accompanying drawings, where Figure 1 is a side view of the plough part concerned; and Figure 2 is a plan view. Figure 3 illustrates part of the support between the lower moldboard and the land side of the frame.

DESCRIPTION OF AN EXEMPLIFYING EMBODIMENT

The front attachment (1, 2) for the lower moldboard (3) is made pivotally movable, by screwing a plate (2) into existing holes intended for the attachment of the lower moldboard (3) to the frame (5); see Figures 1 and 2. A support (1) is welded on the plate (2) at 90 degrees to the frame of the upper moldboard, having a vertical inclination of 13 degrees. A strong joint (7) is welded to the inclined support and passes through the planar land side (5) on the upper frame.

The rear attachment for the lower moldboard (3) passes via screw (8) through a rubber block (4) measuring 200x100 mm and designed to resist pressure against the land side but to be flexible when subjected to vertical forces.

The hardness of the rubber block (4) ranges from 70 shore to 55 shore and controls the ability of the lower moldboard (3) to vibrate when moved forwards against the constantly irregular undersurface. The lighter the earth (soil), the softer the rubber block, and the stiffer the earth, the harder the rubber block, etc. The hardness of the rubber block can be varied by means of its screw (8), so as to enable the block to be adjusted with respect to the quality of the earth concerned and its stone content.

Figure 3 is a view that illustrates the placement of the support (1) between frame (5) and lower moldboard (3).

The above described arrangement can be varied in many ways within the scope of the accompanying Claims.