Lawn working implement

A lawn working implement having rigid teeth which is towed behind a small tractor or other such apparatus to thatch, sow or work a lawn. The implement is compact and highly maneuverable, yet applies pressure to its rigid tines to work the lawn effectively and efficiently. Swivel mounted wheels allow the implement to follow the tractor directly in its path so that confined areas of yards may be reached. The height of the tines above ground may be adjusted by varying the setting at which the wheels are attached to the frame, and their pressure against the ground may be adjusted by adding bricks, cement or other heavy material to a cavity in the implement. The implement has a hitch for attaching a sweeper or lawn vacuum to be towed behind it.

BACKGROUND OF THE INVENTION 
This invention relates to an implement having rigid teeth which is towed 
behind a small tractor or other means to thatch, sow or work a lawn. The 
implement is compact and highly maneuverable, yet applies needed pressure 
to its rigid tines to work the lawn effectively and efficiently. 
Previous towed ground working implements have typically been designed for 
working large areas. Such implements include that disclosed in U.S. Pat. 
No. 4,308,920 issued Jan. 5, 1982, to Floyd, et al. The Floyd, et al. 
implement, which is towed behind a tractor, has a frame with rigid teeth 
depending from it, and rigidly mounted wheels. A relatively long tongue 
connects the implement to a tractor. 
The implement disclosed in U.S. Pat. No. 2,731,896 issued Jan. 24, 1956 to 
Wurster comprises a light weight frame with many knife-like tines 
depending from it. That implement has no wheels and is connected to the 
rear of a tractor by an upper adjustable link and two lower hydraulically 
operated links. Instead of trailing in the path of the tractor, it 
actually acts as a rear appendage of the tractor to till and work the 
ground. Because the links connecting the implement to the tractor are 
relatively long, the implement may present difficulties in working ground 
in confined areas such as yards or on lawns. 
U.S. Pat. No. 1,272,294 issued July 9, 1918 to Mize discloses a harrow 
having several rows of rigid teeth depending from it. The harrow is 
supported by three wheels, the front two of which are rigidly mounted so 
as to be adjustable in height. The harrow has a seat for an operator and 
is drawn by a horse or a team of horses. It is connected to the horses by 
a relatively long tongue and a draft-line. 
U.S. Pat. No. 2,246,946 issued June 24, 1941 to Lupo discloses a smaller 
implement than those mentioned above, which may be used for working 
smaller areas. It has rigidly mounted wheels, however, which inhibit easy 
turning and maneuvering in small areas. A relatively long tongue is used 
to connect this implement to its motive means. 
U.S. Pat. No. 4,091,879 issued May 30, 1978 to Lomberk, et. al. and U.S. 
Pat. No. 2,953,210 issued Sept. 20, 1960 to Bauserman disclose 
hand-operated garden or lawn working tools having rigid tines. These, of 
course, are highly maneuverable, but are difficult to connect to a tractor 
for sustained mechanical power. 
SUMMARY OF THE INVENTION 
The implement of the present invention has a compact frame with a short 
tongue to connect it to the lawn tractor or mower behind which it is 
towed. Swivel-mounted wheels allow the implement to follow the tractor 
directly in its path so that confined areas of yards may be reached, such 
as odd-shaped areas around shrubbery and areas around curbs, houses and 
trees. Despite its small size, the rigid teeth of this implement allow it 
to dig and pull vigorously at the lawn surface to loosen dead grass 
clippings and other material. The implement has a cavity for carrying 
bricks, cement or other heavy ballast material, so that this digging and 
pulling action of the teeth may be adjustably varied. The wheels are 
mounted so that the height of the tines above the ground may be varied, 
for the same purpose. To remove material loosened by the tines, the 
implement has a hitch for towing a vacuum or sweeper behind it. 
It is therefore an object of this invention to provide a lawn working 
implement that may be used to thatch, sow or otherwise work lawns, yards 
or confined areas. 
It is another object of this invention to provide a lawn working implement 
that is easily maneuverable and that follows directly in the path of its 
tractor or motive means. 
It is a further object of this invention to provide a lawn working 
implement having rigid tines that dig and pull vigorously at the lawn 
surface being worked. 
It is further object of this invention to provide a lawn working implement 
in which the pressure exerted by the tines against the lawn surface, as 
well as the height of the tines above the lawn surface, may be varied or 
adjusted. 
It is still another object of this invention to provide a lawn working 
implement having a short tongue connecting it to its tractor or motive 
means so that it may easily be moved in forward or in reverse. 
Other objects, features and advantages of this invention will become 
apparent in light of the description and claims below.

DETAILED DESCRIPTION OF THE DRAWINGS 
FIGS. 1, 2 and 3 show one embodiment of the lawn working implement 11 of 
this invention. Frame 13 comprises two transverse members 15 and two 
longitudinal members 17. In the preferred embodiment, transverse members 
15 are pieces of 1/4".times.3".times.28" (6 mm.times.76 mm.times.71 cm) 
angle iron whose ends are mitered at a horizontal angle of 45 degrees, and 
longitudinal members 17 are each pieces of 1/4".times.3".times.6" (6 
mm.times.76 mm.times.152 mm) angle iron whose ends are also mitered at a 
horizontal angle of 45 degrees. The ends of these members are welded 
together in the preferred embodiment, but may be attached by any other 
suitable method such as nuts and bolts. Transverse members 15 and 
longitudinal members 17 are assembled so that they form a cavity in the 
upper surface of frame 13 to receive bricks, concrete, dirt or other 
material for adjusting the weight of implement 11 and therefore for 
adjusting the force with which its tines are applied against the lawn 
surface. Transverse members 15 and longitudinal members 17 may, of course, 
be formed of other materials, such as extruded aluminum or alloys. 
Wheels are adjustably connected to the side portions of frame 13. In the 
preferred embodiment, wheel brackets 19 of 3/8".times.2".times.4" (10 
mm.times.51 mm.times.102 mm) flat iron are welded to the outer surfaces of 
longitudinal members 17. To the upper and outer portion of each wheel 
bracket is welded a strut mount 21. Strut mounts 21 are 2 inch sections of 
2 inch (51 mm) square tubing, oriented so that the axis of the tubing is 
parallel with the vertical axis of frame 13. Each strut mount 21 has a 
threaded hole 23 for receiving a set screw 27. In the preferred 
embodiment, set screws 27 are 9/16 inch lock or jam bolts having a 1/2 
inch shank and 21/2 inch length. 
Each strut mount 21 of the preferred embodiment receives a strut 29 
attached to a wheel 31. The struts 29 of the preferred embodiment are 1/2 
inch (13 mm) square rod 7 inches in length, but their length and thickness 
may be varied to accommodate the configuration of wheel brackets 19 and 
strut mounts 21. Wheels 31 are connected to the bottom portions of struts 
29, as by welding or other means. Wheels 31 in the preferred embodiment 
are 4 inch casters, but they may be any other type of wheel mounted so 
that they may swivel with respect to frame 13. 
A tongue 37 is connected to the forward portion of frame 13 for towing 
implement 11. In the preferred embodiment, a tongue mount 33 comprising a 
piece of 3/16".times.3".times.7" (5 mm.times.76 mm.times.178 mm) channel 
iron is welded to the center of the forward transverse member 15 in an 
upright orientation. Tongue 37 is welded to the upper portion of tongue 
mount 33, so that it extends forward and rearward from tongue mount 33. In 
the preferred embodiment, tongue 37 is a piece of 
3/16".times.2".times.171/2" (5 mm.times.51 mm.times.191 mm) channel iron 
welded horizontally to tongue mount 3. In the preferred embodiment, a 
forward hitch 39 and an after hitch 41 are mounted on the forward and 
rearward portions of tongue 37, respectively. Forward hitch 39 in the 
preferred embodiment comprises two pieces of 3/16".times.11/2".times.33/4" 
(5 mm.times.38 mm.times.95 mm) flat iron having a 1/2 inch hole drilled 
therethrough. After hitch 41 comprises one piece of 
3/16".times.11/2".times.33/4" (5 mm.times.38 mm.times.95 mm) flat iron 
having a 1/2 inch hole drilled therethrough. Forward hitch 39 is used to 
connect implement 11 to a tractor or other motive means, and after hitch 
41 is used to attach a sweeper or vacuum to the implement. In the 
preferred embodiment, stabilizer rods 43 attached to the forward 
transverse member 15 and to the side portions of tongue 37 stabilize 
tongue 37 laterally. These rods in the preferred embodiment are 1/2 inch 
(13 mm) in diameter and 15 inches long, and are welded to forward 
transverse number 15 and tongue 37. 
Tines 47 extend from the lower surface of frame 13 of the implement in the 
present invention. In the preferred embodiment, tines 47 are 4 inch long 
3/8 inch square (102 mm.times.10 mm) steel rods welded to the lower 
surface of frame 13 so that they are in two staggered rows and spaced 
three inches apart from one another. The rows in the preferred embodiment 
are spaced 31/2 inches (89 mm) apart, but any suitable spacing may be 
used. 
As illustrated in FIG. 4, tines 47 may also be mounted to frame 13 by 
inserting them into tine openings 49 formed in frame 13 and locking them 
in collars 51 mounted to frame 13 above or below tine openings 49. Collars 
51 have set screws 53 threadably inserted therethrough for holding tines 
47 in place. Collars 51 may be sections of appropriate tubing, such as 1/2 
inch or 5/8 inch inside diameter tubing. Alternatively, tine openings 49 
may be threaded openings to receive threaded tines 47 held in place by jam 
nuts 57 as shown in FIG. 5. 
Tines 47 may be mounted according to the above mentioned method or any 
other suitable method, so that they extend in a direction normal to the 
bottom surface of frame 13. In the preferred embodiment, however, tines 47 
extend 10 degrees forward of normal, so that the angle defined by their 
front surface and the bottom surface of frame 13 forward of them is 
between 75 and 85 degrees, and preferably 80 degrees. This orientation of 
tines 47 allows them to act as hooks in conjunction with tongue 37 and 
frame 13, as may be visualized by reference to FIG. 2. The resulting 
hooking action serves to prevent implement 11 from riding on the ends of 
tines 47, and causes more effective gouging or working of the ground 
surface. 
Tines 47 have flat bottom surfaces in the preferred embodiment. These 
surfaces are not perpendicular to the longitudinal axes of tines 47 in the 
preferred embodiment, but define an angle of between 65 and 75 degrees 
with the front surface of tines 47 and between 105 degrees and 115 degrees 
with the rear surface of tines 47. Where tines 47 are mounted for removal 
as with collars 51 or jam nuts 57 mentioned above, they may be removed and 
sharpened. Particularly appropriate with such an embodiment is a tine 47 
having a pointed end better to engage the lawn being worked. Of course, 
any other suitable end shape may be used. 
The foregoing description of the present invention is for purposes of 
explanation and illustration. It will be apparent to those skilled in the 
relevant art that modifications and changes may be made to the invention 
as thus described without departing from its scope and spirit.