A PLOUGH BEAM ASSEMBLY FOR MOUNTING ON A PLOUGH FRAME

A PLOUGH BEAM ASSEMBLY FOR MOUNTING ON A PLOUGH FRAME

This invention relates generally to a plough beam assembly for mounting on a plough frame.

It is well known to provide an auto-reset type of plough beam assembly for incorporating in a reversible plough and having a substantially horizontal support beam, a robust mounting plate provided on a forward end of the support beam and which is connected to the plough frame via an auto-reset mechanism, a pair of opposed plough beams provided on a trailing end of the horizontal support beam and extending upwardly and downwardly from the support beam, and a respective one of a pair of reversible plough bodies mounted on the outer end of each plough beam i.e. on the upper and lower ends respectively of the upwardly and downwardly extending plough beams.

It is usual to mount each plough body on the respective beam end via a saddle, and this determines the spacing of each plough body from the horizontal support beam i.e. the height of each plough body when in an upper inoperative position. If it is required to increase the effective length of each plough beam i.e. to increase the vertical spacing of each plough body from the horizontal support beam, then it is known to insert a distance piece between each beam end and the respective saddle.

The means whereby the plough bodies can be reversed, by rotation of each plough beam assembly, will be well known to those of ordinary skill in the art, and need not be described in detail herein.

In addition, in an auto-reset type of plough beam assembly, it is usual for the horizontal support beam to be hollow, so that a spring-operated reset mechanism can extend through the hollow interior of the support beam, and be connected via suitable connecting brackets to a spring mechanism, which is effective to reset the plough beam assembly when required. Thus, in the event that a ground force acting on the plough bodies moves the support beam relative to the plough frame via a yieldable connection between the mounting plate and the plough frame, the reset mechanism returns the mounting plate to a datum position relative to its connection with the plough frame. Again, auto-reset types of spring operated mechanisms are well known, and need not be described in detail herein. Also, instead of a spring^operated reset mechanism, it is also known to use a hydraulic cylinder with a gas accumulator to provide a resetting force.

In one known reversible plough of the non auto-reset type, there is a mid-section mounted centrally on the horizontal support beam, and having respective- plough beams mounted thereon and projecting upwardly and downwardly therefrom, and in which a separate design of plough beam is required for right side and left side plough bodies accordingly.

In another known non auto-reset type of reversible plough, a one piece beam formation is centrally secured to the horizontal support beam, and forms two separate plough beam portions. As usual, the plough bodies are secured to the plough beam ends via respective saddles.

In both of the known arrangements (of the non auto-reset type), the plough beams are solid, and are fastened to the side plates of the saddles.

The invention seeks to provide an improved design of plough beam assembly for incorporation in a plough frame, and which has technical and / or cost advantages over these known arrangements.

According to the invention there is provided a plough beam assembly for mounting on a plough frame which includes a substantially horizontal support beam having a mounting plate at one end for connecting the support beam to a mounting part of plough frame; and in which:

(a) the plough beam assembly includes a plough beam having an inboard end by which it can be mounted on the support beam and an outboard end to which a respective plough body can be secured via a saddle;

(b) the plough beam is hollow, and is adapted to be pivotally mounted on the support beam at its inboard end;

(c) the inboard end has a shearable connection which holds the plough beam against pivoting relative to the support beam when mounted thereon, up to a predetermined shear force; and,

(d) a rigid insert is housed within each inboard end and is arranged to resist inward deformation of the wall of the hollow beam. Therefore, in a plough beam assembly according to the invention, there is the advantage of a lightweight construction (by reason of the hollow plough beam), but which has a strengthened construction at the inboard end (where the shearable connection is located) by reason of the internally located insert which can resist inward deformation of the wall of the hollow beam.

In one preferred embodiment, the plough beam assembly is intended to be incorporated in a reversible plough, and therefore a pair of oppositely extending plough beams is provided, extending upwardly and downwardly from an opposite end of the support beam, and in which:

(a) each plough beam is hollow, and is pivotally mounted on the support beam at its inboard end;

(b) each inboard end has a shearable connection to the support beam which holds the plough beam against pivoting relative to the support beam, up to a predetermined shear force;

(c) a rigid insert is housed within each inboard end and is arranged to resist inward deformation of the wall of the hollow beam; and,

(d) the two plough beams are of the same construction.

Furthermore, it is possible for the plough beams to be of identical construction, and which gives unit cost and stocking advantages over existing arrangements, in which existing arrangements the plough beams are "handed" i.e. a separate design of plough beam is required for left hand and right hand side plough bodies.

In a preferred arrangement, the outboard end of each (hollow) plough beam has mounting plates thereon, to strengthen the beam structure and to provide a mounting to which a respective saddle can be secured. This saddle can be of standard design and construction.

Preferably, the mounting plates have sets of mounting holes, to allow adjustment of the position of the saddle in order to vary the "height" or spacing of the plough body from the horizontal support beam.

If required, an auto-reset facility may be provided, and such a possibility is within the scope of this invention, and which may be applied to reversible ploughs and non- reversible ploughs. The inboard end of each hollow plough beam preferably is secured to the support beam by means of a pair of mounting plates, which are bolted to the plough beam via a pair of bolts, one of which forms said pivotal connection and the other of which is a shear bolt. Also, it is preferred that the insert takes the form of a spacer or "shim" which forms a rigid assembly with the wall of the hollow beam, and which preferably has a pair of mounting holes which receive the pivot bolt and the shear bolt.

If an auto-reset facility is required this may be provided by a reset mechanism preferably comprising an external spring, and a tensile connection running internally of the horizontal support beam, and which is operative to return the mounting plate and support beam to a datum position relative to a yieldable connection of the mounting plate to the plough frame. An alternative reset mechanism may include a hydraulic cylinder and gas accumulator, arranged to provide a resetting force.

Preferred embodiments of plough beam assembly according to the invention will now be described in detail, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view, from one side, of a first embodiment of plough beam assembly of the auto-reset type, and intended for incorporation in a reversible plough;

Figure 2 is a side view of the plough beam assembly;

Figure 3 is a sectional view through the inboard mounting end of one of the plough beams of the assembly, taken on the section line A-A in Figure 2 (the inboard end mountings are identical for the two plough beams);

Figure 4 is a view from one side of the plough beam assembly of Figures 1 to 3, and showing plough bodies mounted thereon, and also the detail of the spring auto-reset mechanism;

Figure 5 is an end view corresponding to Figure 4;

Figure 6 is a view from an opposite side to the view shown in Figure 4;

Figures 7 and 8 are further perspective illustrations of the assembly;

Figure 9 is a perspective view from one side of a second embodiment of the invention, which is a single leg auto-reset type plough beam assembly for mounting on a plough frame; Figure 10 is a side view of the second embodiment;

Figure 11 is a front view of the second embodiment;

Figure 12 is a side view of a third embodiment of the invention, in the form of a plough beam assembly for use in a reversible plough, but in which only the rear of the mid-section is used, and is fastened with bolts to the main frame of the plough; and,

Figure 13 is a perspective illustration from the rear of the plough beam assembly shown in Figure 12.

Referring first to Figures 1 to 3 of the drawings, there is shown an auto-reset type of plough beam assembly for incorporation in a reversible plough, and which comprises a substantially horizontal support beam 2 having a mounting plate 1 at one end for connecting the support beam via a yieldable connection to a mounting part of a frame of a reversible plough (not shown).

A pair of plough beams 4 extend upwardly and downwardly from an opposite end of the support beam 2 i.e. the trailing end, and in which each plough beam 4 has an inboard end 4a by which it is mounted on the support beam 2, and an outboard end 4b to which a respective plough body can be secured via a saddle (not shown). The mounting of a plough body on the outboard end of a plough beam is via a saddle, and the construction of a plough body and saddle, will be well known to those of ordinary skill in the art, and need not be described in detail herein.

The plough beam assembly also has a spring-operated reset mechanism (not shown in detail) which again can be of substantially standard construction, and serves to reset the plough beam assembly relative to the plough frame when necessary.

Each plough beam 4 is hollow, and is pivotally mounted on the support beam 2 at its inboard end 4a. Furthermore, each inboard end 4a has a shearable connection to the support beam 2, which holds the plough beam 4 against pivoting relative to the support beam 2, up to a predetermined shear force.

To strengthen the hollow construction of each plough beam 4, a rigid insert is housed within each inboard end 4a (as will be described in more detail below) and which is arranged to resist inward deformation of the wall of the hollow beam.

Therefore, the embodiment of plough beam assembly shown in the drawings has the advantage of a lightweight construction (by reason of the pair of hollow plough beams 4), but which has a strengthened construction at the inboard ends of the beams (where the shearable connections are located) by reason of the internally located inserts which can resist inward deformation of the wall of each hollow beam.

Furthermore, the two plough beams 4 are of the same construction, and which gives unit cost and stocking advantage over existing arrangements, in which existing arrangements the plough beams are "handed" i.e. of separate design according to left hand side or right hand side plough bodies being mounted thereon.

The inboard end 4a of each hollow plough beam 4 is secured to the support beam 2 by means of a pair of mounting plates 3, which are bolted to the plough beam 4 via a pair of bolts, in which bolt 20 forms a pivotal connection, and bolt 21 is a shear bolt (see Figure 1). Shear bolt 21 has a predetermined shear resistance, which if exceeded then allows the respective plough beam 4 to pivot about pivot bolt 20, and a suitable free space 22 is defined between the mounting plates 3, to allow this pivotal movement of the plough beam.

The outboard end 4b of each hollow plough beam 4 has mounting plates 5 which strengthen the beam structure and provide a mounting to which a respective saddle can be secured, and which can be a standard design of saddle (not shown). The mounting plates 5 have more than one set of mounting holes 23, which allow adjustment of the position of the saddle in order to vary the height or spacing of the plough body from the horizontal support beam 2.

The spring-operated reset mechanism is not shown in detail, but may comprise a usual construction of external leaf spring (or coil spring), and a tensile connection running internally of the horizontal support beam 2. Fastening brackets are provided for the spring mechanism, comprising bracket 6 located on support beam 2, and mounting brackets 7 and 8. These brackets can be of standard construction. An alternative reset mechanism which may be used comprises a hydraulic cylinder, and gas accumulator to provide a suitable return or resetting force.

The strengthened construction provided internally of each hollow plough beam 4 at the inboard end 4a takes the form of a rigid insert in the form of a spacer or "shim" 9, and which forms a rigid deformation-resisting construction by being held in assembly by the pivot bolt 20 and shear bolt 21. In addition, pivot bolt 20 is taken through a pair of opposed conical tubular supports 10, which help to maintain a rigid and strong assembly upon tightening of the pivot bolt 20, and shear bolt 21.

The mounting plate 1 provided at the forward end of the support beam 2 is a forged construction, and which is connected via a yieldable connection e.g. a plate spring loaded to engagement with a set of balls on a suitable beam support provided on the frame (not shown) of the reversible plough. The support beam 2 is a horizontal square cross section tube, having end side plates 3 at the trailing end, which mount the inboard ends 4a of the hollow plough beams 4 on the support beam 2, as mentioned above.

The plough beams 4 are hollow, and comprise beam legs made of round tubes, which are roll forged, and then formed into required shape. To prevent the inboard ends of the beams 4 being squeezed inwardly when the bolts 20 and 21 are tightened, the insert or shim 9 is provided, and which has mounting holes to receive the bolts. In one of the holes there is positioned the conical support tube 10, and when the bolts 20 and 21 are tightened, the walls of the support beams 4 and the shim 9 are kept rigidly together like a one piece formation.

The shear bolt 21 in the other hole is a shear bolt which provides resistance to shear loads up to a predetermined maximum, and when it shears, the respective beam leg 4 can pivot about the pivot bolt 20. More precisely, the beam leg 4 with the conical tube support 10 and the shim 9 pivots in the hole in the side plates 3. There is therefore provided the free space 22, as shown in Figure 1, to allow free pivoting movement of the plough beam 4.

The outboard ends 4b of the plough beams 4 have strengthened mounting plates 5, as mentioned above. These are welded plates on both sides of each plough beam, and the mounting plates are machined to get the required straightness. Since both the plough beams 4 are symmetrical, there is no need to provide separate designs of plough beam for left side plough bodies and right side plough bodies.

The provision of separate mounting holes on the outboard ends 4b to allow adjustment of the positions of the saddle when different heights of plough body are required, is technically advantageous over the known arrangements, in which distance pieces are required, as described in the introductory part of the specification. The illustrated embodiment of plough beam assembly shown in Figures 1 to 3 of the drawings therefore has the following advantages: it has a hollow lightweight tubular design, with inserts where extra squeezing resistance is needed; it has an auto-reset mechanism, and an additional shear bolt protection; only one design of plough beam or beam leg design is required, instead of known requirement for left and right variants; and, it is possible to mount the saddle in at least three different heights.

Figures 4 to 8 show the plough assembly of Figures 1 to 3 in more detail, and including the mounting of plough bodies 23 on the plough beams 4, and also showing the spring auto-reset mechanisms in more detail.

Figures 9 and 10 show a single leg type plough beam assembly (a non-reversible plough) to which the invention may be applied, namely hollow plough beam 40, pivot bolt 20 and shearable pin 21, and also the insert 9 and related components described in more detail with reference to Figures 1 to 3. Thus, one leg is omitted, and there is made a modification of the connection plates where the leg is mounted. Also, another spring bracket is mounted on the assembly. This variant of the plough beam assembly may be used instead of known solid auto-reset beams which are used on conventional ploughs.

In the embodiment shown in Figures 12 and 13, this shows a plough beam assembly for use in a reversible plough. However, only the rear of the mid-section is used, and which is fastened to the main frame of the plough with bolts. The beam assembly can then be used instead of known solid fixed beams which are used on existing reversible ploughs.

It should be understood that the invention has wide application to many different types of plough frame, and extends beyond the specific examples described above and illustrated in the accompanying drawings.

Thus, in its minimum form, the invention is concerned with: a single plough beam adpated to be mounted on a plough frame and intended to mount a plough body on its outboard end via a saddle; the plough beam is hollow and is adapted to be pivotally mounted at its inboard end on the plough frame e.g. via a substantially horizontal support beam; the inboard end has a shearable connection which holds the plough beam against pivoting (when the beam is mounted in position) up to a predetermined shear force; and a rigid insert is housed within the inboard end and is arranged to resist inward deformation of the wall of the hollow beam.

The invention may be applied to reversible and non-reversible ploughs, and with or without auto-reset mechanisms.

The invention is therefore applicable to all kinds of plough and, in addition to the disclosed embodiment, include the following variants.

A. Conventional (non-reversible ploughs) provided with one of the following:

1. auto-reset beams as shown in Figures 1 to 8, but modified to accommodate one leg only:

2. auto-reset beams as shown in Figures 9 and 10:

3. fixed beams as shown in Figure 12, but modified to accommodate only one leg:

B. Reversible ploughs with:

1. auto-reset beams as shown in Figures 1 to 8:

2. auto-reset beams as shown in Figures 9 and 10:

3. fixed beam as shown in Figure 12.