GB2378374A

GB2378374A - Grass cutting and collecting machine

Info

Publication number: GB2378374A
Application number: GB0119276A
Authority: GB
Inventors: Miles Roland William Bozeat
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-08-08
Filing date: 2001-08-08
Publication date: 2003-02-12
Also published as: GB0119276D0

Abstract

An improved grass cutting and collection machine has within it a continuously recirculating airflow 2 carrying cut grass which airflow leaves the cutting chamber 3 spirally and upwardly and around cut grass separator 8 and thence via return duct 15 to the radial flow fan 1 whence the airflow 2 was created the cut grass carried in the airflow 2 is separated from the said airflow tangentially with both a vertical and horizontal component to the trajectory of the cut grass into the rear confines of the grass collecting box or boxes.

Description

A FURTHER IMPROVED GRASS CUTTING AND COLLECTING MACHINE This invention relates to a further improved grass cutting and collecting machine.

UK Patent GB 2 298 7775B, Claim 1, reveals an improved grass cutting and collection machine wherein there subsists means to create a continuously circulating airflow preferably by a radial flow fan the said airflow being directed towards ground datum and thence upwards into a cutting chamber whereupon the said airflow collects grass cut by blades housed within the said cutting chamber and via a duct leaving the said cutting chamber and thence via a port exiting said duct which port is positioned at a highest practical point within the confines of the volumetric area contained by the demountable grass collecting box or boxes thence via circumnavigation of a structure positioned within the volumetric confines of the said collecting box or boxes so to separate the said cut grass tangentially from the said airflow and to deposit the said cut grass in the said grass collecting box or boxes thence via a second port positioned at the highest practical point upon a second duct which duct is housed within the volumetric confines of the said cut grass collecting box or boxes thence via the said second duct to the said means wherein the said low air flow is created.

The efficacy of the above improved cut grass and collecting machine can be enhanced by further improvements to :- 1. The outlet duct from the cutting chamber so as to minimise any tendency for the machine to clog when in operation and when dealing with different types of grass and particularly wet grass.

2. The management of the recirculating airflow so to take the route of least resistance through the duct leaving the cutting chamber, thence around the grass separating structure and into the return duct and also the airflows within the cutting chamber so as to reduce the amount of power required to drive the radial flow fan and thus to allow the installation of the smallest possible effective fan.

3. Inducing a spirally upward path to the recirculating airflow within the confines of the exit duct from the cutting chamber and around the grass separating structure such that there is tangential separation of the cut grass from the said airflow with a vertical component as well as the already revealed horizontal component so projecting the cut grass to the further confines of the grass collecting box or boxes so to promote the maximum possible potential for complete filling of the grass collecting box or boxes.

4. The management of the recirculating airflow, the airflow generated by the cutter blade and any air lubrication (the hover) airflows that may be present separately or in combination in the cutting chamber so to reduce any unwanted turbulence in the grass collecting box or boxes which inhibit the deposition of cut grass and to reduce the propensity of any cut grass clippings to leave the grass cutting and collection machine beneath the cutting blade and out into the external environment.

It is to the above desirable improvements that this invention provides resolutions.

According to the present invention there are provided improvements to grass cutting and collection machines wherein grass collection is effected by means of a continuously recirculating airflow carrying cut grass from the cutting chamber into a grass collecting box or boxes thence by circumnavigation of a structure within the said grass box or boxes wherein separation of the cut grass from the said recirculating airflow is as a factor of the tendency of all bodies to leave a rotational path at a tangent. The further improvements to the above mentioned machines are effected by providing means whereby the path of the recirculating airflow which recirculating airflow is drawn from the cutting chamber wherein is housed the rotating cutting blade which blade may be aerodynamically configured as in a propeller to support the optimum balance of airflows within the cutting chamber so to provide a maximum avoidance of clogging by cut grass of the exit port from the cutting chamber and undesirable turbulence within the grass collecting box or boxes is via the spirally and upwardly rising exit duct from the said cutting chamber and through the exit port from the said cutting chamber the said airflow continues spirally and upwardly circumnavigating the grass separating structure housed within the volumetric area bounded by the grass collecting box or boxes and the interface with the cutting chamber so separating the cut grass tangentially from the recirculating airflow with both a vertical and horizontal component to the trajectory of the separated cut grass into the rear confines of the grass collecting box or boxes and thence the said recirculating airflow free of cut grass continues into the second return duct and back through the fan into the cutting chamber.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which: Fig. 1/3 is a"transparent"side elevation.

Fig. 2/3 is a"transparent"plan Fig. 3/3 is a"transparent"perspective diagram.

In all drawings only those elements essential to the operation of the invention are illustrated, handles, wiring, power sources and control gear have been deleted for clarity.

Radial flow fan 1 draws a continuously recirculating airflow carrying cut grass 2 from the cutting chamber 3 via a spirally and upwardly rising duct 4 which duct 4 is open towards ground datum 12 thence through a port 5 formed at the interface 6 between the grass collecting box or boxes 7 and the cutting chamber 3 the said recirculating airflow 2 continues spirally and upwardly circumnavigating the cut grass separation structure 8 so separating the cut grass 10 from the airflow 2 as a factor of the tendency of all material to leave a rotational path at a tangent the said separating gives both a vertical and horizontal component to the tangential trajectory of the said separated cut grass 10 the said recirculating airflow 2 enters return duct 15 via return port 11 and thence into the grass cutting chamber 3 via fan 1 said cutting chamber 3 houses a rotating grass cutting blade 13. In this example pressurizing airflow 14 supports the grass cutting and collecting machine in the hover.

Claims

CLAIM 1 A further improved grass cutting and collection machine wherein grass collection is effected by means of a continuously recirculated airflow carrying cut grass from the cutting chamber thence by circumnavigation of a grass separating structure where at separation of the cut grass from the said recirculating airflow is effected as a factor of the tendency of all bodies to leave a rotational path at a tangent within the said further improved grass cutting and collecting machine there is provided means whereby the path of the recirculating airflow is via a spirally and upwardly rising exit duct from the said cutting chamber and thence via spiral and upward circumnavigation of the said grass separating structure so separating the cut grass tangentially from the recirculating airflow with both a vertical and horizontal component to the trajectory of the separated cut grass into the rear confines of the grass box or boxes thence to the return duct returning the said recirculating airflow to the cutting chamber via the radial flow fan CLAIM 2 A machine as claimed in Claim 1 wherein the rotating grass cutting blade is so shaped as to have aerodynamic properties as in a propeller so to divert the airflow created by the said rotating grass cutting blade from the rotating plane of the said rotating grass cutting blade.

CLAIM 3 A machine as claimed in either of Claims 1 and 2 wherein the recirculating air return duct is external to the volumetric confines of grass collecting box or boxes.

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CLAIM 4 A machine as claimed in any of Claims 1,2 and 3 wherein the spirally upward path of the recirculating air around the grass separating structure and within the return duct has induced within it a tightening of the said spirally upward path as a factor of the shape of the said grass separating structure and the configuration of the said return duct.

CLAIM 5 A machine as claimed in any of claims 1, 2,3 and 4 wherein tangentially cut grass separation from the recirculating airflow occurs within the volumetric area bounded by the grass collecting box or boxes and the interface of the said grass collecting box or boxes with the cutting chamber CLAIM 6 A machine as claimed in any of claims 1,2, 3,4 and 5 wherein the machine is supported above the ground datum by virtue of a wheeled chassis.

CLAIM 7 A machine as claimed in any of claims 1,2, 3,4 and 5 wherein the machine is supported above the ground datum by virtue of air lubrication in a hover.