AU2008100505B4 - Shielded Spray Boom For Zero Turn Mower - Google Patents

Description

Description This invention is an addition to a zero turn lawn mower that converts it into a spray rig for the efficient and safe spraying around trees on plantations or similar applications.

In establishing plantations, weed control tends to be the most expensive and time consuming process of the whole endeavour. Small trees tend to be too week to handle being hit by sprung spray units, and using standard spray units in a criss-cross method results in massive amounts of over spray which becomes cost prohibitive.

Other spray rigs on the market for pulling behind 4 wheelers or the like, tend to not have the manoeuvrability required, and allow spray drift, which either kills the plants you are trying to grow, or significantly reduces their growth rate. Rear mounted sprayers also require the user to be constantly turning their heads which becomes very uncomfortable and may cause long term damage. Plus, the user cannot see the spray nozzles obscured by the trailer, so any failure may not be noticed, meaning potentially miss spraying large areas.

There are also hand held booms which have the needed manoeuvrability, but are too slow and taxing on the person walking with the boom to be practical for large plantations, plus they have the spray drift problem.

These problems are overcome by our present invention, which is a low cost shielded boom sprayer, purpose built and attached to the front of a zero turn lawn mower, towing a trailer containing the spray.

With this the user can weave in and out of the trees, only needing to look straight ahead, with minimal or no drift even on high wind days.

The front attachment consists of a half cylinder of standard 225mm drainage pipe (cut in half), with four square slots evenly spaced along the top, above which is mounted a standard 1.2 meter hard plastic threaded pipe, with 4 standard boom spray nozzles evenly spaced over the slots at a height that allows the user to see the spray enter the shield without being subject to drift (tip flush with slot).

On the flat edges of the cylinder are screwed 2 sheets of aluminium which are held in place by 2 large pieces of rubber (see picture), which solidify the structure of the unit and splay out at the bottom to allow the spray to hit the ground without hitting the edge of the unit. To these are attached a standard water deflecting skirt from a truck mud guard (using standard attachments as on a truck guard). This forms a flexible interface between the ground and the unit, allowing travel over rough terrain while preventing spray drift.

The shielded spray unit is held to the front of the mower by 2 arms connected to 2 or 3 standard engine mounts per arm, creating a rigid, but flexible connection that allows the unit to travel over rough terrain without breaking the unit. On the mower are welded 2 nuts with 2 u-bolts that the arms are bolted to (through a bush welded to each of the arms). This is the pivot point, the far end of the arms connect through an adjustable chain which is attached to the mower floor and a hook on the arm. This allows height adjustment. See picture.

The unit is fed by a hose that runs back to the standard spray tank mounted on a small trailer base towed behind and is operated by the lawn mowers battery, being connected with a simple set of alligator clips and operated by a switch located on the support arm of the spray rig, which allows removal of the entire spray rig in less than a minute.