GARDEN TOOL
Technical Field
The present invention relates to garden tools and
more specifically, to hand operable weeding tools.
Background Art
Many types of weed control methods and tools have
been developed for the garden industry. Several non-chemical manual weed
control methods have been used, and most involve cultivation with sharp edged
blades of some type fixed to handles. These blades are manipulated about the
soil to disrupt weed growth, sever weed roots, and dislodge them from the soil.
The blade type garden tool of U.S. Pat. No.6,415,874 and others commonly known
as cultivators, hoes, hand plows and Cape Cod Weeders for example, are only
partially effective due to the fact that they sever weed roots off underground
leaving roots that may then re-grow. Additionally many of the dislodged weeds
will also re-grow in their new location if they are not subsequently picked up
for disposal, thus adding to the inefficient work involved. Also, the sharp
edged blades often nick and damage the roots of desirable plants growing nearby
and therefore render these tools ineffective around the closely spaced
plantings found in many gardens.
It is to be noted that the aforementioned and all
other referenced patents and applications are incorporated herein by reference
in their entirety. Furthermore, where a definition or use of a term in a
reference, which is incorporated by reference herein is inconsistent or
contrary to the definition of that term provided herein, the definition of that
term provided herein applies and the definition of that term in the reference
does not apply.
Another type of weed control is individual weed
removal. For example U.S. Pat. Nos. 1,061,175 and 5,375,401 and 5,535,833 show
grip type weeding apparatuses utilizing a cutting blade and a pivotal claw
arranged to close against the surface of the blade thus pinching the weed for
removal. These types of tools tend to be somewhat useful for picking up weeds
and debris but fail to be effective for pulling plant material from the ground
due to their single point or narrow edge pinching mechanisms which apply their
gripping pressure over a very small surface area. This tends to crush and tear
or sever the plant material at a concentrated pinch area instead of holding it
firm enough to be pulled out of the soil intact. Other designs for example U.S.
Pat Nos. 437,466 and 3,276,805 and 4,400,029 and D206544 have incorporated cup
or opposing channel sections that trap the weed but these also tend to crush
and/or sever the majority of roots and or become clogged and need repeated
cleaning.
U.S. Pat.Nos. 5,234,241 and 7,063,168 and 7,845,696
show various methods utilizing a plurality of spikes or blades coming together
to trap the plant and root structure to be removed. Some of the above noted
tools are effective in removal of larger weeds with tough tap roots, for
example dandelions typical in lawns, but they are generally large cumbersome
tools designed for use by a standing operator using both hands and sometimes
feet as well. These tools are generally expensive to manufacture and do not
address the issue of smaller weeds and grasses most common among typical
vegetable or flower gardens where a smaller hand operated tool suitable for
both tap root weeds and multi-rootlet type weeds would be better suited.
Attempts have been made to create a plier-based
hand-weeding tool but these too have failed in several ways. For example in
U.S. Pat. No. 2,239,108 the jaws come together at a relatively narrow peak
along their length and again this dull knife-edge tends to concentrate forces,
severing tender roots instead of gripping them for removal. U.S. Pat. No.
4,274,619 shows an improvement in gripping and leverage but does not address
the vital root system as the above ground stem is the only portion of the plant
grasped and often the stem snaps leaving the underground roots in place to grow
again. U.S. Pat No.4,389,065 shows an improvement in gripping technology using
rubber gripping pads but due to the blunt design necessitates first digging
around the weed or plant to expose the root structure for gripping adding
unnecessary work and in addition the handle structure is not user friendly.
Avid gardeners are all too well aware that complete
removal including the roots of a weed plant is always the best option for
preventing re-growth of the same weed. Often the most effective and quickest
method of weed control for many gardeners is to resort to using their hands, or
more specifically their fingers, to grip and remove individual weeds and roots
and dispose of them entirely. In addition to this method being hard on ones
hands, especially where spiny weeds are an issue, the main problem is that even
strong fingered individuals will have difficulty in firmly gripping and pulling
stubborn well-rooted weeds, for example buttercup weed. Many weeds like
buttercup are also very prone to root stem breakage when pulled and when broken
or crushed become slimy and even more difficult to grip. Of course those
portions left behind grow again exacerbating the problem.
As a consequence of all the aforementioned problems,
there remains a real need to provide improved methods and apparatus for hand
weeding gardens, which grip and remove entire weeds efficiently without
crushing, severing, or breaking roots, and without clogging.
Summary Of The Invention
The present invention is directed at improved methods
and apparatus for hand weeding gardens. One aspect of the claimed invention
provides a plier like hand tool having a jaw with a distributed force gripping
zone. This gripping zone acts to distribute, rather than concentrate, gripping
forces in order to effectively grip and remove weeds and other plants,
including their roots, from the soil without crushing, severing, or breaking
roots, and without clogging the apparatus. Another aspect of the claimed
invention provides a tool as above with the gripping zone having an opening
that allows the soil and weed debris to exit the tool upon repetitive use.
Among the many possibilities contemplated, a
preferred embodiment uses opposing jaws pivotally coupled and biased to a
normally open position and takes advantage of a distributed force gripping
zone. The jaws have teeth and gripping surfaces, not necessarily perpendicular
to the plane of jaw rotation, such that when the jaws are closed a space
remains between the gripping surfaces to prevent crushing the plant material.
The space can be tapered narrower towards the tip of the jaw. A portion of up
to 95% in area of the distributed force gripping zone can comprise a space
between jaw walls and/or an opening through which soil and plant debris can
exit upon repetitive use making the tool more effective and self cleaning.
A preferred embodiment is compact and fully
operable with only one hand but a larger embodiment made for two handed use in
firm soil or on larger stubborn weeds, can have an elongated or extendible
handle or be adapted to accept a longer handle. A handle can be comprised of
more than one material and generally has a profile that prevents a users hand
from slipping on the handle when applying force to it.
An embodiment can use handles inline with the jaw
axis but in a preferred embodiment handles are at an angle to the jaw axis.
Another contemplated embodiment employs a force multiplying system to increase
the force being applied to the jaws and in yet another embodiment a portion of
the jaws are sharpened for use as a shear type cutter for additional
functionality.
Various objects, features, aspects, and advantages
of the present invention will become more apparent from the following detailed
description of preferred embodiments of the claimed invention, along with the
accompanying drawings in which like numerals represent like components.
Brief Description of Drawings
A more complete understanding of the claimed
invention can be gained by viewing the accompanying drawings and descriptions
of preferred embodiments in which:
Fig.1 is a side elevation view of a preferred
embodiment of the claimed invention in an open biased state.
Fig 2 is a side elevation view of the embodiment in
Fig. 1 in a closed state.
Fig 3 is a side elevation view depicting the
embodiment in Fig.1 in use.
Fig.4 is an isometric view of the embodiment in Fig
1.
Fig.5 is an exploded view of the embodiment in Fig.1
Fig 6 is a front view of the embodiment in
Fig.1.
Fig.7 is a top plan view of the jaw section of the
embodiment in Fig 1.
Fig.8 is a cross sectional view of the jaws in an
open state according to the embodiment in Fig 1.
Fig.9 is similar to Fig.8 only depicting the jaws in
a closed state
Fig.10 is a side view of a second embodiment of the
claimed invention with handles inline with the jaws and a cutter.
Description of Embodiments
DETAILED DESCRITPION OF THE DRAWING
A preferred embodiment of the garden tool will now be
explained with reference to FIG. 1 through FIG. 9 and an alternate embodiment
with reference to FIG. 10. Turning now to FIG. 1, there is depicted one
embodiment of the claimed invention generally referenced by numeral 10
portraying a basic concept of the inventive matter. The garden tool 10
comprising a first member 12 and a second member 14 pivotally coupled at a
pivot point 16 by a pivot pin 18. A portion of first member 12 defines a first
handle 20, while a portion of second member 14 defines a second handle 22.
Another portion of member 12 defines a first jaw 30, while another portion of
member 14 defines a second jaw 32.
In a preferred embodiment the jaws 30 and 32 are
fastened to the handles 20 and 22 with rivets 28. The jaws can also be fastened
to the handles by screws, or glue, or any other suitable mechanical or
non-mechanical means. The jaws can also be insert molded or cast into the
handles or made as an integral part of the handles, for example an entire
member can be formed from one piece of sheet metal or formed in a single piece
molding or casting. The jaws are preferably made from stainless steel sheet
metal but can be made from any suitable material including those that are
castable or moldable and those that are not.
The pivot pin 18 in a preferred embodiment comprises a
threaded metal bolt and nut 66. Other pivot pins, methods, and materials,
suitable for the application are also contemplated including screw and washer
fastening methods, rivets, dowels, shafts, or pins of suitable material. For
example, the pivot on an alternate injection molded embodiment (not shown) is
contemplated as being an integral shaft protrusion acting as the pivot pin on
one member and a mated integral bearing on the other member with a screw and
washer securing the two members in a rotational coupling.
In a preferred embodiment the jaws are biased to an
open state as depicted in FIG.1 by a torsion spring 62 that fits in a cavity 60
in handle 20 as shown in FIG.5. Other suitable biasing means, mechanical and
non-mechanical, are contemplated, including but not limited to, all manner of
springs, magnets, pneumatics, and manual force. When the handles are brought
together they close the jaws along a jaw axis 34 as shown in FIG.2 to engage
the weed or plant for removal as shown in FIG.3.
A preferred embodiment is made to be fully operable
with only one hand without the need to dig around and expose weed roots for
gripping. The jaws are generally profiled to easily penetrate garden soil
around a subject plant. A preferred embodiment incorporates ergonomic design
including for example, texture for grip, appropriate handle shape and curvature
to provide comfortable handgrip, wrist angle, and fatigue reduction. A
preferred embodiment is lightweight at less than 1 kilogram, preferably less
than 500 grams and more preferably less than 250 grams. The handles 20 and 22
in a preferred embodiment are made of injection molded resin. The handles can
also be made of wood, metal, or any suitable hard or soft material including
materials that are castable or moldable, and those that are not. Handles can
also be made of multiple materials, some which might include for example soft
plastic, foam, or rubber coatings. The additional materials can give more
textured surfaces to enhance grip or further enhance comfort, for example with
softness, warmth or cushion.
Both handles 20 and 22 in a preferred embodiment
extend from their associated jaw on the same side of the jaw axis 34 at a
handle angle 36. The specific handle angle is to be understood as non-limiting
and as contemplated and shown in the embodiment of FIG. 10 can even be parallel
to the jaw axis. The specific handle angle is a design choice dependent on the
shape and profile of the handles and jaws of the embodiment. For example, while
an embodiment can have up to a 90 degree handle angle, in my preferred
embodiment I have found that an angle 36 of approximately 50 degrees is most
comfortable and allows the most versatility of use. However an embodiment with
elongated handles designed for use while sitting functions better with a lessor
angle of approximately 25 degrees while straight embodiment or one designed for
a standing user can be effective with no angle at all. It should also be noted
that a handle might also be defined as a lever in certain embodiments.
The FIG.1 embodiment shows a projection 24, on handle
22, which gives a profile providing a brace for the operators’ hand, between a
thumb and forefinger, preventing the hand from sliding towards the pivot point
16 when force is applied to the tool while inserting it into a soil medium. A
similar projection 26 is shown for the operator’s fingers on handle 20. It is
contemplated that multiple smaller ergonomic projections can also be used, for
example including one for each finger. A protrusion can be added to prevent the
hand from slipping in the other direction as well. It is contemplated that one
or both handles can be elongated or telescopically extendible. A longer handle
allows for a two-handed grip, may facilitate stand up use, and can be useful
for increased pressure application against a harder soil medium or bigger weed.
It is further contemplated that the jaws or handles can be adapted to accept
connectable handles of different lengths. For example a handle or a jaw could
be adapted to accept a standard threaded broom handle or other suitable
threaded or unthreaded handles. Thus it can be understood that a wide range of
handle configurations are made possible.
FIG.7 is a top plan view of the jaw portion of a
preferred embodiment showing jaws 30 and 32 having a distributed force gripping
zone 40 comprising, physical gripping surfaces 42, teeth 44, and a perimeter 46
around a jaw wall 48 defining an opening 50. The opening 50, defining a
non-physical gripping area, leads to an open passageway 52 between the jaw
walls as depicted in FIG.8.
The opening 50 and open passageway 52 improve the
distributed force gripping zone by relieving crushing forces on a large area
and enabling a flow through design of a jaw allowing repeated use with minimal
build up of debris. It seems counter intuitive that a non-existent or
non-physical gripping surface area, defined by the opening and passageway
between the jaw walls and comprising up to 95% of the gripping zone, would
still function without a physical surface to work with. Surprisingly though, I
have found that providing an opening by removing a portion of the gripping
surface, including up to the entire gripping surface that would otherwise form
the base of a channel formed by the jaw walls does not affect the function of
the gripping zone. Instead, the open passageway formed considerably improves
the effectiveness of the tool and the gripping zone by reducing the handle
force needed to grip a weed and more importantly by further reducing and
distributing the forces applied to the weed without crushing it. The weed
crown, main root and surrounding soil are held within the confines of the
gripping zone, including the open passageway, while the branching rootlets are
held within the space between the teeth. No crushing, pinching, or severing of
the weed occurs and entire weed is easily removed from the soil. Only one jaw
needs to have this unrestricted open passageway to be effective, however having
two jaws with this feature is superior. A further benefit results when the jaw
is able to self-clean as each new “mouth full” pushes the last mouth full of
debris out through the passageway. Of course an opening does not have to
comprise such a large portion of the gripping zone to still be effective at
improving the distribution of forces and reducing the crushing effect of a
normal gripping zone. I have experimented with different amounts from 10
percent to 95 percent of the gripping zone forming the opening and found
effectiveness increases with the larger percentages.
FIG.8 and FIG.9 are sectional views of the jaws
depicting them in open and closed states respectively. FIG.8 and FIG.9 show
gripping surfaces 42 and teeth 44 in this embodiment are formed at an angle 70
other than perpendicular to a plane 72 of jaw rotation or in this case the jaw
wall 48. The plane 72 of jaw rotation being the plane the jaws move in when
opening and closing. The jaw walls can also be angled to plane 72 either
positively or negatively but in the preferred embodiment they are parallel. The
angle 70 of the gripping surfaces increases the surface area available for the
distribution of gripping forces while reducing crush points.
When the jaws are in a closed state, there is a space
74 remaining between the gripping surfaces and between the teeth as depicted
clearly in FIG 2. I have found it beneficial that the space increase in size
towards the pivot point to reduce the chance of severing larger roots as they
are generally gripped further into the jaw. Smaller roots, generally gripped
nearer the tip of the jaw, do not need as much space to avoid being crushed or
severed.
FIG. 4 and FIG 7 show the jaws in a preferred
embodiment have a bend at an angle 38A that brings each left and right jaw wall
to meet at their distal ends where the angle is reversed 38B and they are
fastened together with a spacer 64 between them. The spacer 64 can be spot
welded or riveted in place or even eliminated. The spacing can be accomplished
by other means, for example the distal end of a jaw wall can have an angled
tab, either vertical or horizontal, which meets and is joined to a tab from, or
directly to, the other wall to form the spacing between the distal ends. If a
space is not desired, the distal ends of the jaws can simply be joined
together. The entire jaw can also be formed from a piece of tubing or one piece
of sheet metal bent to shape. Angle 38A enables the formation of a wedge shaped
space between the jaw walls that increases in size towards the pivot point 16.
The wedge shaped space allows the jaw walls to act as additional gripping
surfaces as a substance is pulled by distributing gripping forces to a larger
volume of substance and increasing holding power through a jamming or packing
of the wedge space, rather than a crushing action. Again, this further
distribution of forces is particularly useful when pulling on weeds as it
avoids over pinching and severing roots, a problem that plagues other weed
gripping tools. A less preferred embodiment does not have angle 38A or 38B and
the space between the jaw walls forms a generally rectangular, oval, or similar
shape, that is slightly less effective as it does not increase the holding
power by the wedge packing action but still remains very effective.
The terms tooth and teeth are used herein to mean an
element from a class of both shapes, including ridges, groves, undulations,
columns, pointed, rounded, dull, sharp, faceted, smooth, jagged, large, small,
and of materials, including those that are hard, and soft, protruding from the
jaw or comprising a gripping surface. I have found the inclusion of at least
one tooth in the gripping zone helps prevent the gripped substance from
slipping from the tools’ grasp. Additionally I have found a plurality of medium
size teeth to be more effective than a higher number of smaller teeth, which
tend to clog with debris and become ineffective. I have also found that teeth
with an angle of approximately 45 degrees inward or outward relative to the
plane of jaw rotation provide additional force distributing surface areas and
reduce the chance of severing a root. Other angles, for example 20 degrees or
65 degrees also work although somewhat less effectively and non angled teeth
are the least effective as they provide minimal distribution of forces.
FIG.10 is a side view of a second embodiment of the
claimed invention wherein the handles are essentially parallel with the jaw
axis 34 and wherein a portion of the jaws near the pivot are adapted to work
together as a shear type cutter 80 for additional functionality. An adjustable
locking bail is depicted in FIG.10. There are many other kinds of commonly
known simple locking mechanisms that can also be employed to lock the jaws in a
closed position when not in use. The bail 82 in FIG.10 has a threaded nut and
bolt making it adjustable so that it can also function as a force multiplier to
increase the pressure applied to the jaws when gripping a substance. Further
embodiments are contemplated having other force multiplying components to
increase the gripping force exerted by the jaws. Force multiplication can be
achieved in many ways including for example, additional members and pivot
points, cam and follower systems, or divergent slot and pin systems.
Having explained at least one embodiment of the
present invention in detail, it is to be understood that the claimed invention
is not limited in its application to the details of construction or to the
arrangements of the components set forth in the description or illustrative
drawings herein as such may of course vary. Those skilled in the art will
appreciate the multiple possible configurations that would be considered to
fall within the scope of intent of the claimed invention. For example the
claimed present invention can comprise a multitude of other tooth and or jaw
geometry’s, profiles, and or configurations. The relative angle between the
jaws and handles can be any degree and the handles can be attached to elongated
handle sections possibly including lever mechanisms for stand up use and or can
employ various known force multiplying methods to the handles or jaws. In
addition the handles depicted can be formed in or have added to them any of the
many possible ergonomic shapes and or materials for functionality and comfort.
The present description is a simplistic form of the claimed invention and has
used a construction of sheet metal attached to a molded handle for illustrative
example.
The claimed invention can be manufactured in many
other forms and with materials including but not limited to sheet or cast
materials, coated materials, laminated or machined materials, injection molded
materials including reinforced polymers, natural materials including wood, or
combinations thereof. Other fabrication methods including die-casting,
laminating, machining, injection molding, and stamping can be used to
manufacture a device incorporating the claimed invention. Any such forms,
embodiments, or materials and methods of manufacture would be considered to
fall within the scope and intent of the claims of the present invention.
It is also to be understood that the terminology used
herein is for the purpose of describing particular embodiments only, and is not
intended to be limiting, since the scope of the present invention will be
limited only by the appended claims.
Where a range of values is provided, it is understood
that each intervening value, to the tenth of the unit of the lower limit unless
the context clearly dictates otherwise, between the upper and lower limit of
that range and any other stated or intervening value in that stated range is
encompassed within the invention. The upper and lower limits of these smaller
ranges may independently be included in the smaller ranges is also encompassed
within the invention, subject to any specifically excluded limit in the stated
range. Where the stated range includes one or both of the limits, ranges
excluding either or both of those included limits are also included in the
invention
Unless defined otherwise, all technical and scientific
terms used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this invention belongs. Although any methods
and materials similar or equivalent to those described herein can also be used
in the practice or testing of the present invention, a limited number of the
exemplary methods and materials are described herein.
It must be noted that as used herein and in the
appended claims, the singular forms "a", "an", and "the" include plural
referents unless the context clearly dictates otherwise.
Thus, specific compositions and methods of a gardening
tool have been disclosed. It should be apparent, however, to those skilled in
the art that many more modifications besides those already described are
possible without departing from the inventive concepts herein. The inventive
subject matter, therefore, is not to be restricted except in the spirit of the
disclosure Moreover, in interpreting the disclosure, all terms should be
interpreted in the broadest possible manner consistent with the context. In
particular, the terms "comprises" and "comprising" should be interpreted as
referring to elements, components, or steps in a non-exclusive manner,
indicating that the referenced elements, components, or steps may be present,
or utilized, or combined with other elements, components, or steps that are not
expressly referenced.
As indicated previously, while specific embodiments
of the claimed invention have been described in detail, those skilled in the
art will appreciate that various modifications and alternatives to those
embodiments can be developed in light of the details and teachings thereof in
this disclosure. Accordingly the particular descriptions, drawings and
arrangements of the disclosure are meant to be illustrative only and not
limiting as to the scope of the claimed invention which is to be given the full
breadth of the claims below and any and all equivalents thereof.