TITLE: "TOP DRESSING MACHINE FOR TURF"
BACKGROUND OF THE INVENTION
THIS INVENTION relates to a top dressing machine for turf. SUMMARY OF THE INVENTION
To promote a healthy growth of turf it is usually desirable to top dress it periodically with sand or light soil with which suitable fertilizers may be mixed. To achieve optimum results it is desirable that the sand or soil should be applied evenly around the grass roots and not form a layer covering the grass. Working the top dress:ng into turf to achieve this result is usually a laborious and time consuming process. The present invention has been devised with the general object of providing particularly efficient and labour saving apparatus for the effective appli¬ cation of top dressing to turf.
With the foregoing and other objects in view the invention resides broadly in a top dressing machine for turf including a mobile main f ame, a hopper for top dressing material on the main frame; feed means for feeding top dressing material from the hopper at a controlled rate; and spreader means for impelling the fed top dressing material to an area over which the main frame is advanced. Preferably the feed means is an endless belt conveyor for carrying top dressing material from the hopper and the spreader means is a rotary brush for sweeping the material from the con- veyor and impelling it downwardly. The machine preferably includes loading means, being a digging bucket carried by a lifting frame which can be moved to bring the bucket to its digging position so that, by reversing the machine the bucket may be driven into and filled with top dressing material which, by
swinging the bucket up to a discharging position, may be emptied into the hopper. Other features of the invention will become apparent from the following description. BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the invention is shown in the accompanying drawings, wherein:
FIG. 1 is a side elevational view of a top dressing machine according to the invention, its trans- mission box being omitted for clarity;
FIG. 2 shows, to larger scale, the transmission box omitted from FIG. 1 and the contained drive assembly;.
FIG. 3 is a plan view of the machine; FIG. 4 is a detail drawing, to larger scale, taken along line .--. in FIG. 3; and
FIG. 5 is a detail drawing along line 5-5 in FIG. 3, to larger scale.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The top dressing machine illustrated includes a main frame 10, generally of rectangular box-like form, having rigidly secured to its front a forwardly conver¬ gent draw-bar frame 11 with a front hitch 12 for connection to a tractor (not shown). The main frame is supported on pneumatically-tyred wheels 13. Preferably two sets each of, say, three wheels 13 are carried adjacently on two aligned axles 1. mounted on under¬ carriage frames 15 secured under the main frame 10. A hopper 16 is mounted within the main frame
10, and has parallel sides 17 and downwardly convergent front and rear ends 18 and 19- The hopper is covered by a removable mesh screen 20, which is reinforced by stays 21 tensioned obliquely across the top of the hopper.
At the bottom, the hopper 16 is open and located closely above an endless conveyer belt 22 carried on parallel front and rear rollers 23 and 24, its upper run being supported at intervals by inter- mediate idler rollers 25. To maintain the conveyor belt in correct alignment endless chains 26 are secured along its side edges and engage idler sprockets 27 at the sides of the main frame.
The rear conveyor roller 24 is located some distance behind the bottom of the hopper rear end 19 and the belt, in passing around this roller, is con¬ tacted by a rotary brush 28 on a shaft 29 rotatably mounted behind the main frame 10.
A hydraulic pump (not shown) is mounted on a platform 30 on the draw-bar frame 11 and may be driven from the tractor's power take-off shaft (not shown) to draw hydraulic fluid from a cooling tank 31 to operate the machine's hydraulic system, including a variable speed hydraulic motor 32 fixed under one side of the rear of the main frame 10.
A drive from the hydraulic motor 32 to both the shaft 33 of the rear conveyor roller 24 and the rotary brush shaft 29 is enclosed w .thin a transmission box 34, shown particularly in FIG. 2. Within this box the output.shaft 35 of the hydraulic motor 32 carries a small sprocket 36 which is connected by an endless chain 37 to a sprocket 38 on the rear conveyor roller shaft 33- This chain 37 also engages a small sprocket 39 fixed on a shaft 40 on which is also fixed a larger sprocket 41. The sprocket 41 is connected by an end¬ less chain 42 to a small sprocket 43 on the rotary brush shaft 29. The rear conveyor roller 24 is thus driven to cause the upper run of the conveyor belt 22 to move from front to rear and the rotary brush 28 is driven rapidly to sweep down over the belt 22 as it
passes down around the roller 24.
A pair of fulcrum arms 44, extending to the rear of the main frame 10, are braced to the main frame by oblique stays 45 and have at their rear end clevises 46 in which are pivoted two side arms 47 of a lifting frame 48. From their pivots the arms 47 con¬ verge to a digging bucket 49, to the sides of which they are rigidly secured. The lifting frame 48 may be swung down to bring the bucket 49 to digging position, or up to bring it to discharging position, by means of a pair of hydraulic rams 50, their cylinders pivoted to brackets 51 on opposite sides of the top of the main frame 10, the pistons of these rams being pivoted to brackets 52 on the lifting frame arms 47- To load the top dressing apparatus, it is backed, with its digging bucket 49 lowered, to a supply of top dr'essing soil until the bucket is ade¬ quately charged. Stiffeners 53 reinforce the bottom of the bucket. The lifting frame 48 is then swung upwardly and forwardly by means of the hydraulic rams 49 until the bucket 49 is in its discharging position over the main frame 10, the contained soil then being discharged gravitationally into the hopper 16 by way of the mesh screen 20, which excludes large lumps of soil.
For top dressing turf, the machine is drawn over the area to be treated with the hydraulic motor 32 operating to drive the conveyor belt 22 and the rotary brush 28. The soil feeds gravitationally to the conveyor belt at a rate which prevents undue loading on the belt due to the provision of a pair of spaced baffles 54 across the lower part of the hopper, these baffles being triangular in cross-section, their front faces beingat a smaller angle to horizontal than their rear faces, the leading edge of the front baffle
being somewhat closer to the conveyor belt 22 than that of the rear baffle.
The moving conveyor belt 22 carries top dressing at a controlled rate under a flow-regulator gate 55 below the rear end 19 of the hopper 16. As shown particularly in FIG. 4, this gate is an arcuately curved plate 56 reinforced by an oppositely curved back plate 57 and secured at its end on a pair of sector- shaped end plates 58 having outwardly extending stub axles 59 pivoted in bearings 60 at opposite sides of the main frame 10. A gate handle 61 fixed to one of the stub axles may be operated to bring the leading edge of the curved plate 56 closer to or further from the conveyor belt 22, and thus determine the depth of soil carried from the hopper by the conveyor.
Undue loss of top dressing between the bottoms of the hopper sides 17 and the conveyor belt 22 is prevented by the provision of resiliently flexible sealing strips 62 attached to mounting pieces 63 fixed to the lower sides of the hopper, the sealing strips, as shown particularly in FIG. 5, being inclined to bear firmly on the side portions of the conveyor belt 22.
The top dressing carried at a controlled rate from the hopper is acted upon by the rotary brush 28 which, rapidly rotated, sweeps the top dressing from the rear of the conveyor belt 22 and impels it down¬ wardly with some force, so that to a significant extent it is driven down through the grass blades to settle around the grass roots.
By varying the speed of travel of the machine, the setting of the flow-regulator gate 55 and the speed of the conveyor belt 22 and rotary brush 28, an operator can easily and conveniently control the rate of speed of the top dressing. When the supply of top
dressing has been exhausted from the hopper, it may be quickly and easily re-charged by use of the digging bucket 49, as described.
Turf top dressing machine according to the invention will be found to be very effective in achiev¬ ing the objects for which they have been devised. It will, of course, be understood that the particular embodiment of the invention herein described and illustrated may be subject to many modifications of constructional detail and design, which will be readily apparent to skilled persons, without departing from the scope of the invention hereinafter claimed.