GB2088181A

GB2088181A - Spray boom suspension system

Info

Publication number: GB2088181A
Application number: GB8136096A
Authority: GB
Original assignee: L & K Engineering Ltd
Current assignee: L & K Engineering Ltd
Priority date: 1980-11-28
Filing date: 1981-11-30
Publication date: 1982-06-09
Also published as: GB2088181B; AU8415182A

Abstract

A transverse spray boom (2) is mounted on tie rear end of a mobile crop-spraying machine through the medium of a suspension system having at least one suspension unit interposed between the boom and a machine frame and comprising pivotally connected elements (1, 4) secured to the boom and frame respectively, one of which elements is provided with resilient means (3) which is deformable in response to movement of the element secured to the frame relative to the other element to absorb said movement and prevent it from being transmitted to the boom. <IMAGE>

Description

SPECIFICATION Suspension system This invention relates to suspension systems and is particularly, though not exclusively, concerned with the suspension of booms on cropspraying machines and fertiliser-spreading machines.

When applying chemical orfertiliser by means of such machines it is important to maintain the distance between the spreading or spraying device, be it nozzle, plate or disc or whatever, and the target area, substantially constant to ensure evenness of application. Also, because of the dimensions of the boom and the generally rough terrain traversed by the machine it is important to minimise the amount of movement transmitted from the machine to the boom due to the uneven ground and thus minimise stressing of and consequent damage to the boom.

It is accordingly a principal object of the present invention to minimise transmission of movement from the chassis of the machine to the boom and to this end, according to the invention, at least one suspension unit is interposed between the boom and that part of the machine which follows the contours of the ground, said unit comprising two pivotally connected elements for connection to the boom and said other part of the machine respectively, one of which elements is provided with resilient means which is deformed in response to relative movement of said elements and prevents transmission of such movement to the boom.

It is a further object of the invention to minimise yawing movement of the boom and to this end, according to a further feature of the invention, the or each suspension unit is interposed between the boom and an intermediate back frame which is pivotally mounted on a fixed frame secured to the chassis of the machine, for movement about a vertical axis under the control of at least one further suspension unit interposed between said intermediate back frame and said fixed frame.

Various embodiments of the invention will be described with reference to the accompanying drawings in which: Figures 1 and 2 illustrate a preferred form of suspension unit in its unloaded and loaded conditions respectively; Figures 3 and 4 show in diagrammatic form two alternative applications of the suspension unit shown in Figs. 1 and 2 Figures 5 and 6 are diagrammatic views showing two suspension units and their alternative forms of connection to the boom; Figure 7 shows the suspension units of Figs. 5 and 6 connected to the boom by links; Figures 8 to 10 are side, rear and plan views of a spray boom mounted on the tank frame of a spray unit through the medium of two suspension units arranged as shown in Fig. 7;; Figures 11 to 13 are views similar to Figs. 8 to 10 showing anti-yaw control means interposed between the tank frame and the boom suspension means; Figure 14 is a diagrammatic view from the rear illustrating the movements of the chassis to be absorbed by the suspension shown in Figs. 8 to 10; and Figure 15 is a diagrammatic view from above illustrating the movements of the chassis to be absorbed by the suspension shown in Figs. 11 to 13.

Referring to Figs. 1 and 2 a preferred form of suspension unit comprises a casing 1 shown secured to the underside of a spray boom 2 and containing four rubber rollers 3, and an arm 4 carrying a stub axle 5 to be secured to a mobile spraying machine. The end of the arm 4 remote from the stub axle 5 is provided with a squaresection shaft 6 which enters the casing 1 and is adapted, on pivotal movement of the arm relative to the casing in response to movement of the spraying machine over uneven ground, to deform the rollers 3, as shown in Fig. 2. The rollers 3 thus absorb the movement of the arm and prevent its transmission to the boom 2.

In the arrangement of Fig. 3 the casing 1 of the suspension device is mounted on the chassis 7 of the spraying machine and the arm 4 is connected to the boom 2 in such a manner that the boom will move with the chassis about its longitudinal axis, but vertical movements of the chassis will be absorbed by the suspension device.

The arrangement shown in Fig. 4 is similar to that shown in Figs. 1 and 2 except for the fact that the casing 1 of the suspension device is mounted on top of the boom 2 which is thus not affected by movement of the chassis 7 either vertically or about its longitudinal axis.

Figs. 5 to 7 illustrate the use of two suspension units each having its casing 1 mounted on the chassis 7 of the spraying machine. In Fig. 5 the arms 4 of the suspension units are pivotally secured to the boom 2 at fixed points 8 while in Fig. 6 the ends of the arms are slidably and pivotally mounted in slots 9 for either unrestricted movement or movement limited by springs, rubber cushions or the like (not shown). In Fig. 7 the arms 4 are shown as being connected to the boom 2 by pivoted links 10 to permit even greater freedom of movement of the chassis 7 relative to the boom.

Figs. 8 to 10 are more detailed views of the arrangement shown in Fig. 7 using the same reference numerals to indicate identical parts. In these figures the reference numeral 11 indicates a frame fixed to the chassis of the spraying machine for mounting a spray tank (not shown), the bouncing and rolling movements of the spray tank, absorbed by the suspension units being indicated diagrammatically, by the arrows 14 and 1 5 respectively in Fig. 14.

In Figs. 11 to 13 the boom 2 is mounted in the manner shown in Figs. 8 to 10, on an intermediate frame 1 2 which is itself pivotally mounted at 13 on the tank frame 11 with the interposition of two further suspension units, each having its casing 1 secured to the front of the frame 12 and its arm 4 extending horizontally between the casing and a horizontally extending link 10 pivotally connected at its ends to the arm 4 and the frame 11 respectively. This intermediate suspension is designed to absorb pitching and yawing movements of the tank frame 11 indicated by the arrows in Fig. 1 5.

Claims

1. A suspension system interposed between a boom and a mobile surpport therefor, said suspension system having at least one suspension unit comprising two pivotally connected elements for connection to the boom and the support respectively, one of which elements is provided with resilient means which is deformable in response to relative movement of said elements to absorb and prevent transmission of such movement to the boom.

2. A suspension system according to Claim 1, wherein one of said elements comprises a casing secured to one of said boom and said support and containing a plurality of rubber rollers and the other of said elements comprising an arm secured at one end fo the other of said boom and said support and provided at its other end with a square-section shaft which enters said casing and is adapted, on pivotal movement of said arm or said casing relative to the other, to deform said rollers which thus wholly or substantially absorb said movement.

3. A suspension system according to Claim 2, wherein said casing is secured to said boom and said arm is secured to said support whereby pivotal movement of the arm relative to the casing is operative through the square-section shaft to deform the rollers which substantially absorb the movement of the arm and prevent its transmission to the boom.

4. A suspension system according to Claim 2, wherein said arm is secured to the boom and said casing is secured to said support, whereby pivotal movement of the casing relative to the arm is operative to deform the rollers without moving the arm to any appreciable extent.

5. A suspension system according to Claim 4, wherein said arm is pivotally secured to said boom.

6. A suspension system according to Claim 5, wherein said arm is slidable in a longitudinal slot in said boom.

7. A suspension system according to Claim 6, including resilient means for limiting the amount by which said arm is slidable in said slot.

8. A suspension system according to Claim 7, wherein said resilient means comprises a spring or rubber cushion.

9. A suspension system according to any one of Claims 4 to 8, employing two of said suspension units spaced longitudinally of said boom.

10. A suspension system according to Claim 9, wherein each suspension unit includes a pivotal link interposed between said arm and said boom.

11. A suspension system according to Claim 10, for a spray boom which extends transversely of a mobile spraying machine constituting said support and carrying a spray tank for connection to spraying means carried by said boom.

12. A suspension system according to Claim 11, provided at the rear of said spraying machine between a frame carrying said spray tank and said boom.

13. A suspension system according to Claim 12 interposed between said boom and an intermediate frame which is mounted on said spray tank frame for movement about a vertical axis under the control of two further suspension units each having its casing secured to said intermediate frame and its arm pivotable about a vertical axis and connected to said tank frame through a horizontally extending link.

14. A boom suspension system substantially as hereinbefore described with reference to or as shown in the accompanying drawings.

1 5. A mobile spraying machine employing a transverse spraying boom and a suspension system therefor, substantially as hereinbefore described with reference to the accompanying drawings.