Abstrict An improved can crusher which has a pair of pivotal arms responsive
to the position of a piston within an elongated, base mounted tube
for denting or creasing and piercing the side of the can prior to
the crushing the can by the piston. The piston is activated with
a pivotable handle which engages the piston through apertures in
the tube. The pivot arms are mounted to the outside of the tube
and their ends remote from the base are biased toward the axis of
the tube into engagement with the side of the piston. As the piston
moves towards the can, the protruding portions of the upper ends
of the pivot arms are forced away from the axis of the tube thus
forcing protruding portions on the lower ends of the arms into the
side of the can, thereby piercing and denting the can. As the piston
crushes the can, the lower protruding portion is pivoted away from
the can by the action of a biasing spring. The end of the pivotal
handle can be curved to reduce off-axis forces on the piston.
Claims I claim:
1. An improved can crusher comprising:
a piston;
a base;
tube means attached to and extending transversely from the base
and within which said piston can move along a path from an upper
position remote from the base to a lower position proximate the
base, the tube means including means for receiving and positioning
a can to be crushed so that one end thereof is proximate the base;
means for urging said piston along said path from the upper towards
the lower position into engagement with the can to thereby crush
the can by removing the other end of the can towards said one end
thereof, said urging means including a handle having a handlegrip
portion, a piston-engaging portion and a pivot point between said
handlegrip and piston-engaging portions;
arm means connected with the tube means and movable into engagement
with a side of the can, said arm means having a can piercing portion
for denting and piercing the side;
means, activated by the motion of the piston from the upper to
the lower position, for moving the arm means to dent and pierce
the can side before the piston moves the other can end toward the
one can end to thereby facilitate the crushing of the can by the
piston;
wherein the arm means moving means includes means connected with
the piston for forcing said engaging means of said arm away from
said path to thereby pivot said arm in a first direction and move
said piercing means to pierce and dent the side of said can.
2. The can crusher of claim 1 wherein the piston includes an opening
in a side of the piston, and wherein said piston-engaging portion
of said handle extends through the opening to thereby engage the
piston.
3. The can crusher of claim 2 wherein said piston has bearing means
mounted to be contacted by the piston-engaging portion for reducing
friction and the generation of transverse forces on said piston.
4. The can crusher of claim 2 wherein said piston-engaging portion
of said handle is configured to engage said piston so that a resulting
force urging the piston along said path to crush the can is generally
parallel to said path to reduce transverse forces on said piston.
5. Apparatus for crushing metal cans by axially compressing them
so that their respective ends are proximate and generally parallel
to each other, the apparatus comprising:
a can holder including a base and a tube protruding transversely
away from the base, the tube defining a cavity adapted to receive
a can to be crushed generally parallel to the axis of the tube,
the tube including a first cutout proximate the base sized to permit
the insertion of the can therethrough into the cavity, the tube
having an additional length terminating in a free end spaced from
the cutout and from the base, said additional tube length including
first and second generally diametrically opposite slots formed therein,
one of the slots communicating with the first cutout;
a piston having a can engaging end and being axially movably disposed
within the cavity for movement between a first position in which
the piston end clears the can in the cavity and second position
at which the piston end is relatively proximate to the base, said
piston including first and second generally diametrically opposite
apertures aligned with the slots;
means for reciprocating the piston between the first and second
positions, said reciprocating means comprising an elongate handle
having a first length extending generally radially through the slots
and the apertures and a second length which is relatively remote
from the tube, and means connected with the base mounting the handle
and permitting pivotal handle motions about a pivot axis located
between the first and second handle lengths, whereby pivotal movement
of the handle causes corresponding axial movements of the piston
along the cavity;
a piercing and denting arm mounted to the exterior of the tube
generally parallel to the axis of the cavity and being pivotable
about an axis that is transverse to the axis of the cavity, the
arm defining first and second arm portions located, respectively,
between the ends of the can in the cavity and at the additional
length of tube;
the tube being formed so that the first and second arm portions
can alternatively enter the cavity when the arm is pivoted in opposite
directions;
means for pivotally biasing the arm so that the second portion
is normally biased into the cavity;
said piston further including extension means engaging the second
arm portion when the piston moves from the first to the second position
and for pivotally moving the arm against a force exerted by the
biasing means to enter the first arm portion into the cavity, engage
a side of the can in the cavity with the first arm portion, and
pierce and deform the can side before the piston end contacts the
can to facilitate the crushing of the can by the piston, the piston
further including retraction means permitting the biasing means
to pivot the arm and permit the second arm portion to enter into
the cavity to thereby correspondingly retract the first arm portion
from the cavity before the piston arrives at its second position.
6. Apparatus according to claim 5 including a second cutout in
the tube generally diametrically opposite from the first cutout,
the second cutout being dimensioned so that the crushed can can
be withdrawn from the cavity through the second cutout.
Description This invention is related to can crushers, particularly to the
type which weakens the can by first denting the side of the can
prior to axially crushing it.
BACKGROUND OF THE INVENTION
The need to crush empty cans has become increasingly great in recent
years. This applies especially to readily recyclable aluminum cans
which do not normally decompose and therefore present a serious
disposal problem. Often persons who may wish to save aluminum cans
for recycling are deterred from doing so because of the bulkiness
of empty cans and the significant labor that is required to crush
the cans by stepping on them, for example. As a result, can crushers
have been developed.
The prior art can crushers, such as those disclosed in U.S. Pat.
Nos. 3732804; 3780647 and 3934498 as well as British Pat.
No. 1156139 have recognized the need to indent the side of the
can to weaken it prior to crushing. Heretofore the means for indenting
the side of the can have been quite complex, expensive and failure
prone. Further, some can crushers obliterate the ends of the cans
when crushing them. Such crushes are not suitable for areas where
beverage cans have had a deposit paid on them. In such an event
one end of the can typically receives a special mark or designation.
If the can end is obliterated, the deposit might not be collectable.
SUMMARY OF THE INVENTION
The present invention provides a can crusher which axially flattens
the cans to leave their ends unobliterated for identification purposes.
To reduce the crushing force, side-denting arms are pointed to pierce
the sides of the can so that the sidewalls can tear while being
crushed. The can crusher is simple, rugged, and can be constructed
of a few parts. It is therefore both durable and relatively inexpensive
to obtain, operate and maintain. It is adapted to be used when large
volumes of cans need to be crushed as, for example, at public recycling
centers. Yet it is sufficiently inexpensive so that it can be advantageously
used by individuals for crushing cans used in a single household,
for example.
Broadly speaking the can crusher of the invention has a frame that
includes an elongate cavity which holds a can for crushing by a
piston that is axially movable within the cavity. Means is provided
for urging the piston toward the can from a first position in which
the piston clears the can to a second position in which it interferes
with the can so that the can is crushed when the piston is moved
from the first to the second position. The crusher further includes
means responsive to the relative location of the piston in the cavity
for deforming and piercing a side of the can to facilitate its crushing.
In a presently preferred embodiment, the frame of the crusher is
defined by a base and a tube protruding transversely away therefrom.
The tube defines the cavity and has a first cutout proximate the
base which is sized to permit the insertion of the can therethrough
into the cavity and an additional length terminating in a free end
spaced from the cutout and from the base.
The can's side is deformed by a detent arm mounted to the exterior
of the tube and generally parallel to the axis of the cavity. The
arm is pivotable about an axis that is transverse to the axis of
the cavity and defines first and second arm portions located, respectively,
between the ends of the can in the cavity and at the additional
tube length. The tube further includes slots that are arranged so
that the first and second arm portions can alternatively enter the
cavity when the arm is pivoted in opposite directions and a spring
is provided for pivotally biasing the arm so that the second portion
normally extends into the cavity. The arm is of a simple, inexpensive
construction and is readily accessible. Maintenance or replacement
that may from time to time be required is simple and can be readily
performed to prevent long down times and costly repairs.
The piston has extension means which engage the second arm portion
when the piston moves from the first to the second position and
which pivotally moves the arm against the force exerted by the spring
to enter the first arm portion into the cavity, engage a side of
the can in the cavity with the first arm portion, and deform the
can side before the piston end contacts the can to facilitate the
crushing of the can by the piston. The first arm portion is pointed
so that the side of the can is pierced as well as dented. This allows
the side of the can to rip as well as buckle when crushed so that
the axial force required is reduced. The piston is constructed so
that the spring can pivot the arm and the second arm portion can
enter into the cavity before the piston arrives at its second position
to thereby correspondingly retract the first arm portion from the
cavity and prevent the first arm portion from interfering with the
crushing of the can by the piston.
To facilitate the withdrawal of the crushed can, by gravity when
the base is mounted to an upright wall, the tube includes a second
cutout that is generally diametrically opposite from the first cutout
and which is dimensioned so that the crushed can can readily pass
through it. In this manner the crushed can removal is practically
automatic either by gravity or by being pushed out when the next
can is inserted in the cavity. This significantly increases the
operating speed of the crusher without noticeably adding to its
cost. The use of the first cutout adjacent the base permits direct
loading of the can into the cavity. This reduces the length of stroke
required of the piston and this allows the can crusher to be more
compact and further speeds its operation compared with prior art
can crushers.
The piston can be power driven, as with a hydraulic or pneumatic
drive, or it can be manually operated. In the latter case the additional
length of the tube preferably has first and second generally diametrically
opposite slots, one of which communicates with the first cutout.
The piston includes first and second generally diametrically opposite
apertures which are aligned with the slots and an elongate handle
is provided which has a first length that extends generally radially
through the slots and the apertures. A second length of the handle
is gripped by the operator and extends away from the tube. The handle
is mounted to the base to permit pivotal handle motions about a
pivot axis located between the first and second handle lengths so
that a pivotal movement of the handle causes corresponding axial
movements of the piston along the cavity.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the can crusher of the present
invention shown mounted to a wall.
FIGS. 2A, 2B, 2C are cross-sectional views of the tube and associated
components illustrating the piston in three positions.
FIG. 3 is a cross-sectional view of the tube showing the piston
engaging portion of the handle.
FIG. 4 is a partial view of the upper end of the tube of an alternative
embodiment showing a pneumatic piston drive mounted thereto.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now to the Figures, the can crusher 2 generally comprises
an elongated tube 4 mounted upright on a base 6. A crushing piston
8 is disposed within the interior cavity of the tube and is moved
along the axis of the tube by a generaly L-shaped handle 10 which
is pivotally mounted to the base. Movement of the piston along the
axis of the tube causes a pair of coacting pivot arms 12 mounted
to the side of the tube to both dent or crease and puncture the
side of a can A placed within the tube adjacent to the base prior
to the can being crushed by the piston.
Elongated tube 4 is securely mounted to base 6 by integrally constructing
it therewith (e.g. when the tube and the base are molded from plastic),
by bolting it to the base, welding or the like. Normally the base
is mounted to an upright wall B with bolts 22 or the like. The tube
has a first cutout 14 shown in FIG. 1 located adjacent to the
lower end of the tube 16 and sized so that a can can be inserted
through the cutout into the tube cavity. For the purpose of this
description, and the claims, the term "lower" will sometimes
be used to denote "close to" the base, while the term
"upper" will be used to denote the opposite, i.e. relatively
remote from the base.
Piston 8 is driven along the axis of the tube cavity by the L-shaped
handle which is pivotable about a pivot pin 34 carried by posts
35 projecting from the base. The pivot pin engages the handle where
the diverging handle grip portion 18 and the piston engaging portion
20 of the handle intersect. The grip portion 18 of the handle is
typically significantly longer than the piston engaging portion
20 of the handle to provide the user with a significant mechanical
advantage when crushing can A.
The tube includes diametrically opposite slots 36 38 and the
piston includes aligned apertures 24 26 for receiving an end 28
of the piston engaging portion of the handle. Handle end 28 is arcuate
and in use supplies the downward, can crushing force to the piston.
Handle end 28 may engage the piston walls where it extends through
the piston apertures or a pin 30 may be provided which is mounted
to the sides of the piston. The pin passes through the axis of the
piston in a direction transverse to the handle. A roller bearing
32 can be placed over the pin to reduce friction. Further, lateral
forces on the piston are substantially reduced or eliminated by
forming end 28 downwardly concave, as best seen in FIG. 3. The concave
curvature of end 28 is chosen so that no matter what the position
of the piston along the axis of the tube is, the plane which is
tangent to the area of intersection between the handle end and the
bearing is generally perpendicular to the axis of the tube.
For certain applications, particularly when a large volume of cans
must be crushed, the handle 10 can be replaced with a power drive.
For example, a pneumatic (or hydraulic) piston drive 58 (shown in
FIG. 4) can be mounted to an upper end 55 of the tube. Drive 58
is conventionally actuated with compressed air from a compressed
air source 62. In such an event a piston rod 64 engages transverse
pin 30 and forces the piston toward lower end 16 onto the can and
back toward upper end 55.
To facilitate the crushing of cans, which exhibit significant resistance
to axial compression while in their original form, their sides are
both deformed or dented and preferably are pierced preparatory to
crushing. Referring now particularly to FIGS. 2A, 2B and 2C, pivot
arms 12 are provided for this purpose. The arms are pivotable about
a pivot pin 42 carried by spaced-apart brackets 40 projecting radially
from the exterior of tube 4. Preferably, the brackets are positioned
approximately 90.degree. from slots 36 38 in the tube and at approximately
the height of the top of the undeformed can A on base 6. The pivot
pins are perpendicular to the axis of the tube and the brackets
are positioned so that the arms 12 pivot in a plane which passes
through the tube axis.
The arms have upper and lower projecting portions 44 46 which
face toward the tube cavity. The tube has upper and lower slots
48 50 which are aligned with the pivot arms and positioned so that
the projections 44 46 can alternatively enter through the slots
into the cavity of the tube when the arms are pivoted about pin
42. A spring, such as a helical compression spring 52 is mounted
between each arm and the outside of the tube, and is centered over
a stub 53 or the like on the arm which is positioned so that the
spring pivotally biases the upper projection 44 of the associated
arm towards the tube cavity. For purposes further described below,
the upper projection is defined by an upper, generally upwardly
facing surface 47 and a downwardly oriented surface 49 (facing
towards base 6). Both surfaces are angularly inclined relative to
the axis of the tube cavity.
Piston 8 includes diametrically opposite, generally rectangular,
apertures 64 which end short of the piston ends to define opposing,
upper and lower arm engaging edges or surfaces 63 65 respectively.
The arm engaging surfaces 63 65 are located relative to the obliquely
inclined projection surfaces 47 49 so that the arms are pivoted
at the desired moments and in the desired directions during the
crushing of the can. Specifically, the surfaces are arranged so
that upper pivot arm projections 44 can enter the tube cavity when
the piston is retracted, that is when the piston is in its upper
position (FIG. 2A) to allow the insertion of a new can for crushing.
It will be noted that compression springs 53 bias the arms into
that position.
When a can is to be crushed, handle 10 is operated to axially move
the piston in a downward direction. Arm surface 47 and piston surface
63 are arranged so that they engage during the downward motion of
the piston. Upon the engagement of the surfaces, the downward motion
of the piston pivots the arms against the force of the springs 53
so that the upper projections 44 are retracted from the tube cavity
while the lower projections 46 are forced into the cavity. Since
the lower projections overlie the axial extent of can A, the inward
pivotal motion deforms or dents the sides of the can, thereby greatly
reducing the force that is required for axially compressing and
thereby crushing it. Further, by configuring lower portions 46 to
have a sharp point 71 portions 46 also pierce the sides of the
cans as well as deforming it. This allows the sides to both tear
and collapse in response to the axial movement of piston 8. Additional
reduction in crushing force is thereby achieved.
As piston 8 continues to move downwardly, the apex 67 of the upper
arm projections 44 slides along the exterior side of the piston
until it engages the upper surface or edge 65 of the piston. Further
downward movement of the piston permits the downwardly facing, obliquely
inclined arm surface 49 to slide inwardly, towards the tube cavity
under the biasing force of spring 53 thereby retracting the lower
arm projections 46 and permitting the unconstrained crushing of
the can by the downwardly moving piston to the lowest possible height.
Upon the withdrawal of the piston, the upper projection surfaces
47 49 engage the arm actuating surfaces 63 65 of the piston in
reverse order until the piston reaches its fully withdrawn position
illustrated in FIG. 2A. At that point, the lower pivot arm projections
46 are retracted out of the tube cavity, the just crushed can can
be withdrawn from the cavity and a new can can be inserted through
cutout 14.
To facilitate the removal of the crushed can, can-removal aperture
56 is located adjacent to the base and opposite the can insertion
cutout 14. Aperture 56 is significantly smaller than the insertion
cutout to assure that a newly inserted can will be retained in the
tube cavity until after it is crushed. The removal aperture has
a sufficient size to allow the crushed can to be readily removed
therethrough. When the base is mounted to a horizontal wall, it
is arranged so that the removal aperture faces downwardly. In this
manner the crushed can drops gravitationally from the tube cavity
which greatly speeds up the crushing operation since it eliminates
the need for manually removing it. But even if the base were mounted
horizontally, the removal aperture permits a virtually automatic
ejection of the crushed can since the insertion of a fresh can through
cutout 14 necessarily forces the crushed can out of the tube cavity
through the removal aperture.
The can crusher of the present invention is well suited for use
in combination with an automatic can feeder to load cans into the
tube through the can-insertion cutout 14. Such a feeder will typically
be responsive to the position of the piston or to the piston actuating
mechanism. The can-removal aperture eliminates the need for separate
can removal apparatus for the reasons discussed above.
The operation of the can crushing apparatus should now be apparent.
To briefly summarize it, with the piston in the upper load position,
as shown in FIG. 2A, can A is inserted through cutout 14. The handle
is then pulled in the direction of arrow 60 in FIG. 1 to force the
piston downwardly towards the base. The downward motion of the piston
causes the upper projections 44 of the pivotal arms 12 to be forced
outwardly in opposition to the biasing force of the spring; simultaneously
the lower projecting portions 46 as shown in FIG. 2B, are forced
inwardly against the sides of the can thus denting and piercing
its sides. As the piston continues to move downwardly, the upper
edge of the piston passes the upper projecting portions of the pivotal
arm thereby allowing the lower projecting portions of the arms to
pivot away from the sides of the can. The piston continues to be
forced toward the base until the can is crushed, as shown in FIG.
2C. Thereafter, the piston is withdrawn from the base end by moving
handle 10 in the direction of arrow 66 thus forcing end 28 of the
handle against the upper surface 61 of slot 24 (see FIG. 3). The
crushed can is then removed from the tube; normally it will gravitationally
drop through the can removal aperture 56.
Although the best mode contemplated for carrying out the present
invention has been herein shown and described, it will be apparent
that modificaton and variation may be made without departing from
what is regarded to be the subject of the invention. |