CA1139572A

CA1139572A - Gang mowers

Info

Publication number: CA1139572A
Application number: CA000303508A
Authority: CA
Inventors: Raymond G. Whimp
Original assignee: AHI WHIMPWAY Ltd
Current assignee: AHI WHIMPWAY Ltd
Priority date: 1977-05-19
Filing date: 1978-05-16
Publication date: 1983-01-18
Also published as: JPS604687B2; AU524421B2; ZA782833B; JPS5415825A; GB1593698A; AU3615178A; NZ184157A; BE890850Q

Abstract

ABSTRACT OF THE DISCLOSURE;
A gang mower comprises a number of individual reel mowers ganged together, each reel being driven by an electric motor from an electric power source, such as an alternator, associated with the mower, The alternator is typically driven by the same motor that propels the gang mower along.

Description

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Background of the Invention This invention is concerned with improvements in or relating to gang mowers.

Gang mowers comprise a p~urality of individual mowing units which are lin~ed together and which are towed or propelied together~ the arrangement of the gang being such that a much wider swath of grass can be cut in a single pass than is possible with a single mower unit, Gang mowers are commonly used to cut yrass on golf courses, but~ of course, can be and are used in other applications. Usually the reels of the individual mowers are driven from the wheels or by hydraulic motors An example of the prior art is rotary mower described in New Zealand Patent Specificat.ion No 1776~9 of Mul~inorm B V. which describes rotary cutters arranged in pai.rs and preferably driven by hydraulic motors It has now been found, however, that electrically driven reel mowers are more efficient, and are better suited to cutting large areas of grass such as on gol-f courses or airfields It is an object of the present invention to provide a gang mower wherein the reel of each mower unit is driven by an electric motor Mowers which are powered by electric motors are known but are operated from a mains supply, this necessitating an electric cord between the mower and the mains supply which of course, places limitations on the areas which can be covered by such mowers.

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Summary of the Invention _ The present invention provides a gang mower suitable for being propelled along the ground by a driving means, and including a frame, an alternator assembly with securing means, serving to secure said alternator firmly to said driving means, a plurality of cutting reel assemblies includiny a cutting reel mounted be-tween and supported by a pair o wheels, a single electric motor mounted on each said cutting reel assembly and in driving engage-ment with the corresponding cutting reel, and power supply cables connected to supply electric power generated by said alternator assembly to each of the said electric motors, Brief Description of the Drawings The above gives a broad description of the present invention, a preferred form of which will now be described with reference to the accompanying drawings, in which:
Figure 1 is a plan view of a preferred embodiment of the present invention, Figure 2 is a side elevation of the embodiment shown in Figure 1, and Figure 3 is a circuit diagram oE a preferred form of the present invention, Description of Preferred Embodiment According to the embodiment of the present invention illustrated in the drawings a gang mower 1 of the type adapted to be towed behind a towing vehicle 2, such as a tractor, has the reel, 3 of each individual mower driven in use by means of an electric motor 4, there being a separate electric motor for each individual mower.
The drawings show each mower comprising a reel 3 mounted between a pair of wheels 8, towed behind a jockey wheel 18, Many other arrangements are possible, howe~er, For example, ~e mowersco~d allbe 3.tJ ~

mounted on retractable arms, pivoted to a single rigid drawbar. The retractable arms could be operated by hydraulic rams connected to the tractor hydraulic system, so that the arms can be retracted, drawing the mowers in, for convenience of transporting the mower along roads to different mowing areas. Such units do not require the jockey wheel 18.
The reels 3 preferably have a drive connection at each end so that it does not matter which side o the mower the motor 4 is mounted on.
At each side of the box housing the alternator there can be a foot telescopically operable to be raised or lowered.
When lowered the feet provide a support for the housing when it is not connected to a tractor. The feet can be held in either their lowered or raised position by a pin passing through apertures in the vertical column of each foot and in the tube within which the foot column is telescopically slidable.
Associated with the gang mower is an alternator 5, which is driven from tha engine of the towing vehicle preferably by means of a connection to the power take-off 6 of the towing vehicle through a step-up drive, either by a gear box or pulley belt arrangement 13, or alternatively by means of a direct coupling to the crank shaft of the towing vehicle.
The preferred alternator has a 15 kilowatt, 3 phase, 200 volt rating and therefore 3 phase electric motors are used, these preferably ranging ~i ~L3~ P ~
betweem 3/4 -to 3 horsepower in rati.ng though alternators and motors having other specifications can be used, The alternator would be driven at the maker's specified rpm which for many alternators would be about 1500 rpm.

The alternator can be either mounted on a separate frame to be suitable for connection to a three, point linkag~ 7 as commonly used on tractors~ or on the gang mower draw bar 9r or alternatively on a framework which carries the mounted mowers of the gang. The alternator and the electric motors would preferably be drip-proofed or water-proofed so that they would not be adversely afected by use in unfavourable weather conditions, A control box lO is mounted on the alternator unit and protection circuit breakers 11 are incorporated in the control box. Power from the alternator passes through the control box to a plug box 17 which can be mounted on the mower draw bar, or on the tractor, or on framework supporting the alternator, or on framework carrying the mounted mowers ~f the gang, whichever is the most convenient for the type of model and number of mowers in the gang, The control box incorporates one starter 12 for each electric motor of the gang~ The electric wiring between the alternator, plug box and the control box is preferably permanently connected.

Power is fed to the electric motors 4 by means of cables 14 which are re-movably connected to the plug box 17 by plugs 15 which fit into sockets 16 of the plug box.

Also situated within the plug box 10 is a forward/reverse switch 20 which enables -the direction of rotation of the mowers to be reversed and a volt meter 21 for indicating the voltage output of the alternator 5, If desired there may also be an appliance plug 22 from which any 110 volt electrical appliance can be run.

In an alternative embodiment the control box can be mounted directly on the draw bar 9~ doing away with the need for a separate plug box. In this case the cables 1~ would be permanently wired to the control box. A single cable would run from the control box to a power outlet on the alternator housing, and another would run to a remote switch unit near the operator's seat. The meter 21 would also be mounted on the remo-te switch unit, In an alternative form of the invention the gang mower can be of the self-propelled type and in this case the motor of the gang mower is also used to drive an al-ternator or generator, As before, it is preferable that each individual mower of the gang has its own elec-tric motor,

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A gang mower suitable for being propelled along the ground by a driving means, and including a frame, an alternator assembly with securing means, serving to secure said alternator firmly to said driving means, a plurality of cutting reel assemblies including a cutting reel mounted between and supported by a pair of wheels, a single electric motor mounted on each said cutting reel assembly and in driving engagement with the corresponding cutting reel, and power supply cables connected to supply electric power generated by said alternator assembly to each of the said electric motors.

2. A gang mower as claimed in claim 1 wherein the alternator is a three-phase alternator and each electric motor is a three-phase motor.

3. A gang mower as claimed in claim 1 wherein the gang mower is of the towed type and the electric alternator is driven from the crank shaft or the power take-off, if provided, of the towing vehicle.

4. A gang mower as claimed in claim 3 wherein the alternator is within a housing provided with at least one retractible foot so that when the foot is extended the alternator housing can rest on the foot when the mower is not attached to a towing vehicle, and when the foot is retracted a towing vehicle can tow the gang mower without impedance from the foot.

5. A gang mower as claimed in claim 1 wherein the gang mower is of the self-propelled type and the electric alternator is driven by the propelling means of the mower.

6. A gang mower as claimed in claim 1 wherein each reel is drivable from either end.

7. A gang mower as claimed in claim 1 wherein the mowers are each mounted on a hydraulically retractible arm pivoted to a main frame.

8. A gang mower as claimed in claim 1 wherein each mower is pivotally mounted behind a jockey wheel attached to a main frame.

9. A gang mower suitable for being propelled along the ground by an engine driven vehicle, including:
(a) a frame connectable to move with said vehicle:
(b) An alternator assembly securable to said vehicle, said alternator being couplable with said engine of said vehicle, whereby said engine speed and alternator output voltage vary together;
(c) a plurality of cutting reel assemblies attached to said frame said cutting reel assemblies experiencing a load which varies with respect to the ground speed of said vehicle;
(d) each of said cutting reel assemblies including a cutting reel mounted between and supported by a pair of wheels;
(e) a single electric motor mounted on each cutting reel assembly in driving engagement with the corresponding cutting reel; and (f) power supply cables connected to each of said electric motors from said alternator to supply electrical power generated by said alternator assembly whereby when said engine speed decreases, decreasing said vehicle ground speed and the voltage from said alternator, the load applied to said cutting assembly decreases to correspondingly lower voltage requirements for said motor.

10. A gang mower as claimed in claim 9 wherein said alternator assembly is a three-phase alternator and each electric motor is a three-phase motor.

11. A gang mower as claimed in claim g wherein the gang mower frame is towed by said vehicle and the electric alternator assembly is driven from the crank shaft or a power take-off of the towing vehicle.

12. A gang mower as claimed in claim 9 wherein the gang mower is of the self-propelled type and the electric alternator is driven by the propelling means of the mower.

13. A gang mower as claimed in claim 9 wherein each reel is drivable from either end.

14. A gang mower as claimed in claim 9 including a hydraulically retractable arm pivoted to said frame, said cutting reel assemblies of said mower being mounted on said arm.

15. A gang mower as claimed in claim 9 wherein each cutting wheel assembly is pivotally mounted behind a jockey wheel attached to said frame.