Abstrict A concrete crusher has a crushing surface 1a on a stationary lower
jaw 1 and it is formed so that its axial cross-section is V-shaped.
A main crushing blade 5 is installed on a crushing surface 2a of
a movable upper jaw 2 pivoted to the lower jaw and is opposite the
lowermost portion of stationary crushing surface 1a. Supporting
crushing blades 6 are installed on the upper jaw at opposite sides
of the main crushing blade 5 and have shorter blade heights than
main crushing blade 5.
Claims What is claimed is:
1. In a concrete crusher comprising
a lower fixed jaw, and
an upper movable jaw connected by a pivot to the lower fixed jaw
for upper jaw closing movement toward and upper jaw opening movement
away from the lower fixed jaw, the lower fixed jaw having a crushing
surface on which a concrete piece can be received,
the lower fixed jaw crushing surface having a waste passage opening
located centrally therein,
the upper movable jaw carrying a main crushing blade disposed orthogonal
to a jaw pivot axis, the waste passage extending orthogonal to said
pivot axis so that the main crushing blade can enter the waste passage
opening in a terminal part of main crushing blade closing movement,
the improvement wherein
the lower fixed jaw crushing surface inclines downwardly from each
of opposite crushing surface side margins to a crushing surface
low point at said waste passage opening thereby defining a V-shaped
crushing surface profile so that the concrete piece when received
on said crushing surface locates symmetrically of a crushing surface
centerline.
2. The concrete crusher of claim 1 further comprising at least
one supporting crushing blade carried on said upper movable jaw
at each of two opposite sides of said main crushing blade, each
supporting crushing blade extending parallel to the pivot axis and
having a lesser depth than the main crushing blade.
Description BACKGROUND OF THE INVENTION
The present invention relates to a crusher used in the demolition
of concrete structures such as buildings, wall barriers and the
like for crushing concrete building blocks, beams, rubble pieces,
etc.
FIG. 6 depicts a known type of concrete crusher used in building
demolition areas for crushing concrete blocks. This concrete crusher
has a movable upper jaw 12 which is driven by a hydraulic cylinder,
and a stationary lower jaw 11 which can be attached to the end of
a boom or the like on a power shovel. Movable upper jaw 12 is pivot
mounted to stationary jaw 11 by way of an axle O' so that it can
open and close. Concrete blocks and the like are placed between
the respective crushing surfaces 11a, 12a (the surface facing the
other jaw) of both jaws 11 12 and are then crushed and pulverized
by the closing motion of movable upper jaw 12.
In another type of crusher of the prior art as shown in FIG. 7
a crushing blade 15 which bites into and crushes the concrete block
is attached to a crushing surface 12 a (surface facing the lower
jaw) of movable upper jaw 12. Crushing surface 11a of lower jaw
11 is a plane or a planar lattice.
In order to crush evenly and finely and for a blade of the upper
jaw to hit the concrete block accurately in most advantageous striking
location, the preferred position of a scooped up concrete block
or piece to be crushed is to be symmetrical of a center axial position
of crushing surface 11a of stationary lower jaw 11. In reality,
it is often the case that the concrete blocks shift from the center
off to one side when they are scooped up. It is then necessary to
adjust the insertion position back towards the center of the stationary
lower jaw crushing surface by operating the boom, arm, rotating
device, or the like. As a result, operating time is lost, extra
work is involved, and processing speed becomes markedly lower.
In order to respond to shifts in position of the object to be crushed,
the prior art employed multiple crushing blades positioned axially
in multiple locations on the movable upper jaw. If a block is large,
the large number of blades results in multiple blades hitting the
block simultaneously. The biting strength of each individual blade
is weakened, and crushing becomes more difficult.
OBJECT AND SUMMARY OF THE INVENTION
The object of the present invention is to increase the processing
speed of a concrete crusher operation by making adjustment of insertion
position of the concrete block on a crushing surface unnecessary.
A further object of the present invention is to maximize the crushing
strength possible with the crusher by assuring placement of a concrete
block in the crusher at position where maximum crushing strength
is realized.
In order to achieve the above objects, the present invention can
crush a concrete block or like piece by the closing of a movable
upper jaw against the concrete block while it is resting on a stationary
lower jaw, the stationary jaw being attached by an axle or pivot
to the movable upper jaw. The cross-section of a crushing surface
of the stationary lower jaw taken along a jaw pivot axis direction
is of V-shaped, arcuate or like configuration wherein such surface
inclines or depresses toward a low point at a central axial position
of the crushing surface. Such surface configuration facilitates
receptive holding of a concrete block on said surface in position
wherein it is symmetrical of the center axial position of the surface.
A crushing surface of the movable upper jaw has a main crushing
blade which moves in a crushing course coinciding with the lowest
point of the stationary crushing surface. Supporting crushing blades
which have lower blade heights than the main crushing blade are
positioned around the main crushing blade. The main crushing blade
can be a single blade stretched lengthwise along the movable upper
jaw, or it can be multiple blades in a single row.
A waste passage can run through the stationary lower jaw. The waste
opening opens in the lowest point of the stationary crushing surface
of the stationary lower jaw and allows penetration therethrough
of the main crushing blade.
Shredding blades can be attached to both the stationary lower jaw
and the movable upper jaw, where they have a shredding action by
their mutual engagement for the purpose of shearing reinforcing
rods and like components commonly embedded is the demolished concrete
structure.
The above and other objects, features and advantages of the present
invention will become apparent from the following description read
in conjunction with the accompanying drawings, in which like reference
numerals designate the same elements.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a concrete crusher made in accordance
with the invention;
FIG. 2 is a plan view showing of a stationary lower jaw of the
concrete crusher;
FIG. 3 is a vertical cross-sectional view taken on the line A--A
in FIG. 2.
FIGS. 4(a), 4(b) and 4(c) are schematic cross-sectional showings
of successive stages of crushing of a concrete block from an initial
crush stage to a near final crush stage, showing additionally the
manner in which reduced size crushed concrete and other debris pass
through a waste opening in the lower jaw;
FIG. 5 is a cross-sectional diagram on enlarged scale depicting
initiation of crushing of a very large concrete block;
FIG. 6 is a perspective view of a crusher of the prior art; and
FIG. 7 is a perspective view of another prior art crusher.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-3 the concrete crusher 10 of the present
invention has a stationary or fixed lower jaw 1 which is pivoted
as by an axle O to a movable upper jaw 2 which can be opened and
closed. Movable upper jaw 2 is driven by a hydraulic cylinder (not
shown) and opens and closes in the direction of arrow 1 and with
respect to stationary lower jaw 1 the stationary jaw, e.g., being
attached to a boom or the like of a power shovel, such being a common
practice in the art.
Stationary lower jaw 1 has a crushing surface 1a of depressed shape.
The depressed shape can be defined by lower jaw cross-section taken
in a direction along a jaw pivot axis, the cross-section being,
e.g., V-shaped. V-shaped is understood herein to mean a shape wherein
the distance between the two crushing surface parts 1a located on
either side of center line X--X increases gradually as the said
surfaces go upward, i.e., approach opposing movable upper jaw 2.
The incline angle of crushing surface 1a is arbitrary. The left
and right crushing surfaces 1a, 1a can have different incline angles.
Further, either one or both of crushing surfaces 1a, 1a could be
a composite inclined surface with two inclined surfaces with differing
incline angles. The crushing surface 1a are shown as being planar,
but such surfaces could be curved, e.g., of concave shape or even
slight convex shape.
The lowest portion (axial center position) of lower jaw crushing
surface 1a has an opening which communicates with a waste passage
3 passing through stationary lower jaw 1 the waste passage being
provided to facilitate carry away of crushed concrete particles
from crushing surface 1a. The waste passage 3 can be compartmentalized
into plural sections (2 in the FIG. 1 depiction), the waste passage
being disposed in crushing surface 1a orthogonal to the pivot axis.
Waste passage 3 does not have to be in a plurality of passage sections,
but can also be as a single passage.
Crushing surface 2a of movable upper jaw 2 is constructed so that
it is approximately equal in length as crushing surface 1a of stationary
lower jaw 1 length in this respect being the dimension orthogonal
to the pivot axis. Upper jaw carries a main crushing blade 5 installed
lengthwise along movable upper jaw 2 at the axial center of the
latter. In other words, crushing blade 5 is opposite the lowermost
portion of stationary crushing surface 1a and its movement course
during crushing is in a plane coincident with center line X--X.
Main crushing blade 5 has a wave form tip surface 5a.
When movable upper jaw 2 closes, the whole blade can enter waste
opening 3. As seen in FIG. 1 main crushing blade 5 is continuous
in length from rear to front of the upper jaw, but it also could
be made as a number of individual aligned crushing blades forming
a single row in the axial center of crushing surface 2a.
Around main crushing blade 5 (for example on either side) on upper
jaw 2 and orthogonal to the direction of main crushing blade 5 so
same are generally parallel to the pivot axis, are a plurality of
auxiliary crushing blades 6 these being arrayed front to rear spaced
one from another at each side of main crushing blade 5. The frontmost
of these auxiliary crushing blades 6 in each row of such is rectangular,
but the others following in a row can be trapezoidal as clearly
seen in FIG. 1.
Blade heights get shorter going axially towards either side of
movable upper jaw 2. Auxiliary crushing blades 6 all have blade
heights shorter than main crushing blade 5 and thus during operation
reach their crushing position later than main crushing blade 5.
Stationary lower jaw 1 carries at an inner part thereof, a shredding
blade 7. This shredding blade 7 can be used to cooperate with a
like blade (not shown) carried on upper movable jaw 2 to cut or
shear any reinforcing steel or steel frame component mixed in with
the concrete block.
In using the concrete crusher, a hydraulic shovel on which the
crusher is carried is operated and concrete blocks or pieces at
a demolition site are scooped up with stationary lower jaw 1 upper
jaw 2 being in open position. Referring to FIG. 4(a), concrete block
9 is brought to crushing surface 1a of stationary lower jaw 1. Concrete
block 9 naturally will tend to settle at the lowest part of crushing
surface 1a and be symmetrical of center line X--X. In other words,
block 9 will occupy a position centralized on crushing surface 1a.
Referring to FIG. 4(b), when movable upper jaw 2 is closed, main
crushing blade 5 attached to movable upper jaw 2 bites into concrete
block 9 and crushes it breaking it into two or more pieces. Because
crushing blade 5 is attached along central line X--X, crushing of
concrete block 9 into at least two parts will be along approximately
the center of block 9. During and after this crushing, concrete
particles of certain size and smaller can discard from stationary
lower jaw 1 by gravity passing through waste passage 3.
By further closing movable upper jaw 2 supporting crushing blades
6 which reach crushing position later than main crushing blade
5 will crush broken-up concrete blocks 9' to smaller sized concrete
pieces.
With further closing of movable jaw 2 and as seen from FIG. 4(c),
main crushing blade 5 will enter waste passage 3. Because the space
between both sides of crushing surfaces 2a and 1a narrows in the
downward direction, any remaining broken-up concrete blocks are
crushed finer, not only by supporting blades 6 but also by this
closing of crushing surfaces 1a, 2a with the effect that much of
the concrete is rendered to pulverized condition.
After being pulverized, concrete particles will slide off the surface
of stationary crushing surface 1a naturally or by shaking the crusher
using the boom. The particles are disposed smoothly from waste passage
3.
Because scooped up concrete blocks tend to naturally collect in
the center of stationary crushing surface 1a, there is no need to
adjust the concrete block position as in prior art. As a result,
time lost and work involved in adjusting block position is reduced,
and processing speed can be increased.
Because the concrete block is initially crushed by a single (or
a single row) main crushing blade 5 in the axial center of movable
upper jaw 2 crushing strength can be concentrated on the concrete
block for this initial crush which requires the greatest strength.
A smooth crushing is made possible with a small amount of power.
After breaking with the initial crushing, the broken-up concrete
blocks 9' are further crushed by the plural supporting crushing
blades 6 which reach crushing position after the main crushing blade.
Because the concrete block is already broken up, it is possible
to crush with a small amount of power, even with a plurality of
supporting crushing blades.
Because there is a waste passage 3 in stationary lower jaw 1 crushed
particles can be successively removed outside the crushing surface.
There is no need to stop operation due to blockage by crushed parts.
Waste passage 3 will receive main crushing blade 5 in the last step,
and crushing supporting crushing blades 6 and crushing surfaces
1a and 2a can continue to operate to produce as fine a crush as
possible.
Referring to FIG. 5 a wide concrete block is supported at two
points by stationary crushing surface 1a (the two ends of the V-shape).
Because of this, when movable upper jaw 2 closes, the large concrete
block can be broken up along a breaking course at its center. Compared
to prior art with a planar crushing surface and multiple crushing
blades, it thus is possible to break large blocks with far less
power.
In the present invention, concrete and concrete shapes are given
as an example of objects to be crushed, but the present invention
is not limited to this and can be effective with many types of material
such as bedrock, rocks, wood, and the like.
Because the objects to be crushed which are scooped up naturally
collect in the center, processing speed can be increased by reducing
the work and time loss involved in position adjustment. Because
the initial crushing which requires the greatest strength is done
with a main crushing blade, the crushing strength is concentrated
on the object. A smooth initial crushing is possible with a small
amount of power. A wide block can be broken through the center because
the ends of the V-shaped crushing surface support two points on
the block. As a result, a large block can be crushed with a small
amount of power.
A waste passage which opens in the lowermost portion of a stationary
crushing surface is created on the stationary lower jaw and allows
for the entrance of the main crushing blade. Crushed particles can
be successively removed from the crushing surface. There is no need
to stop operation due to blockage by crushed parts. Because waste
passage 3 will receive main crushing blade 5 in the last step, the
crushing process by supporting crushing blades 6 and crushing surfaces
1a and 2a can operate continuously, and a finer crushing is made
possible.
Shredding blades are attached to both stationary lower jaw and
movable upper jaw. Shredding action results from the mutual engagement
of these blades. The cutting of steel reinforcements and steel frames
in the concrete blocks becomes possible, and speeds the demolition
process.
Having described preferred embodiments of the invention with reference
to the accompanying drawings, it is to be understood that the invention
is not limited to those precise embodiments, and that various changes
and modifications may be effected therein by one skilled in the
art without departing from the scope or spirit of the invention
as defined in the appended claims. |