Note: Descriptions are shown in the official language in which they were submitted.
;16
MOBILE PAVEMENT CRUSHER
Field of_the Invention
The present invention relates to a mobile pavement
crusher for crushing pavement material and to a method of
crushing such material.
Review of the Prior Art
_
The increasing cost of pavement construction and
maintenance and the declining purchasing power of public tax
revenues, and also the shortage of non-renewable hydrocarbon
resources, have made the recycling of pavement material an
increasingly desirable objective. This objective is also
desirable in order to slow down the depletion of mineral
aggregrate resource~. Consequently, efforts have already been
made to recycle pavement material, particularly bituminous
pavement material A
This has previously been effected by using a bulldozer
to rip pavements into oversize pieces or chunks, which are
picked up by a front end loader, a bacX hoe or other apparatus
and loaded into trucks. After being hauled by the trucks to a
central location, the pavement material pieces are stock-piled
and subsequently picked up again and fed through a primary
crusher and a secondary crusher to produce a final sized
material acceptable for a recycled pavement material mix~ It
will be evident that this prior method requires repeated
handling of the pavement material.
The repeated picking up and handling of this pavement
material requires the employment of several pieces of equipment
~2~
and, consequently, results in relatively high equipment and
labour costs for the handling of the material.
Definition of the Invention
It is accordingly an object of the present invention to
provide a novel apparatus and method for crushing pavement
material for recycling purposes which substantially reduce the
costs involved in handling the material.
This is achieved, according to the present invention, by
employing a mobile crusher to pick up the pieces or chunks of
pavement material from the ground, to crush these pieces of
material and to discharge the crushed material, preferably into
a truck travelling with the mobile crusher.
Consequently, the present invention entirely eliminates
the need for a front end loader, a back hoe or other equipment
for picking up the pieces of pavement material from the ground
loading them into a truck, and other equipment for subsequently
and picking them up from a stockpile and feeding them to a
crusher, and instead enables the material to be discharged
directly into a truck, already crushed to the required size
suitable for recycling, at the location at which the pavement is
ripped up.
More particularly, according to the present invention,
there is provided a mobile pavement material crusher, comprising
ground engagement members for supporting the crusher for
movement along the ground;
a motor drivably connected to said ground engagement
members for advancing said crusher along the ground;
pick-up means at ground level at said front end of the
- 2 -
~2~4~6
crusher for displacing pieces of broken pavement material from
the ground;
upwardly and rearwardly inclined pick-up elevator means
at a front end of the crusher for picking-up and upwardly
displacing the pieces of broken pavement material from the
pick-up means as the crusher advances along the ground;
means for receiving and crushing said pavement material
from said pick-up elevator means; and
upwardly inclined output elevator means for receiving
said crushed material from said crushing means and discharging it
from the crusher.
. The present invention further provides a method of
breaking and crushing a pavement, comprising the steps of:
advancing a mobile crusher along the ground towards
pre-broken pavement material pieces on the ground;
employing a pick-up mechanism at a front end of said
crusher to lift said pavement material pieces from the ground,
said pick-up mechanism forcing an upwardly and rearwardly
inclined pick-up blade beneath said pavement material pieces and
conveyir.g said pavement material pieces from the rear of said
pick-up blade;
crushing the lifted pavement material pieces in said
crusher; and
discharging the crushed pavement material from said
crusher.
In a preferred embodiment of the invention, a pavement
material crusher is equipped with a pair of primary crusher
rolls and a pair of secondary crusher rolls for successively
.~3
3 -
2~L6:~
crushing the bituminous material, with a vibratory screen in the
path of the material between the primary crusher rolls and the
secondary crusher rolls.
Description of the Drawings
The invention will be more readily understood from th~
following description of a preferred e~bodiment thereof given,
by way of example~ with reference to the accompanying
diagrammatic drawing, in which:-
Figure 1 shows a view in side elevation of a pavement
crusher embodying the present invention, intended for the
crusing of bituminous pavement, parts thereof being omitted and
broken away as necessary for clarity of illustration;
Figure 2 is a plan view from above of the machine of
Figure l;
Figure 3 is a section taken on the line 3-3 in Figure 4
to show a detail of the connection of a front endless track to
the machine chassis and means for steering the said track;
Figure 4 is a side elevation of the said front endless
track and adjacent portion of the chassis and a forward pick-up
elevator;
Figure 5 is a side elevation of a pick-up blade
assembly and the means for effecting vertical pivotal adjustment
thereof;
Figure 6 is a plan view from above of pick-up teeth of
the pick-up blade assembly to show a detail of the construction
thereof;
-- 4 --
Figure 7 is a plan view from above of a rear discharge
elevator of the machine and means for adjust.ing its poisition and
elevation relative to the machine;
Figure 8 is a side elevation corresponding to Figure 7;
Figure 9 i5 a plan view from above to an enlarged scale
of a mounting arran~ement for ths said rear elevator;
Figure 10 is a ~ide elevation corresponding to Figure
9; and
Figure 11 i5 a hydraulic circuit for the machine for
the powering and control of the hydraulic motors thereof~
Description of the_Preferred Embodiment
. The mobile crusher of the invention shown in the
drawings is intended for the crushing of bituminous pavement
mateirial and has a chassis indicated generally by reference 10,
which is supported on ground engagement members in the form of
endless tracks 11 extending around track wheels 12. An elevator
support structure 14 is provided at the front end of the chassis
10, mounted on a front endless track 15 spaced forwardly from
the endless tracks 11. The support structure 14 supports an
upwardly and rearwardly inclined pick-up elevator indicated
generally by reference 17, which extends rearwardly from a
pick-up blade assembly indicated ~enerally by reference 18 and
located at the front end of the bituminous material crusher, to
an upper primary bin or hopper 19.
The pick up elevator 17 has an endless conveyor belt 20
guided over rolls 21, 22 and 23 between upwardly and rearwardly
_
~L2~:!i4~
inclined side walls 25 and 26, the belt 20 being formed, as
shown in Figure 2, with perforations or openings 28 of one and a
half inch diamet~r and being connected to a pair of parallel
drive chains 29. A plurality of slats 30 of two inches height
extend transversely of the conveyor belt 20, and the rear of the
pick-up blade assembly 18 is formed with a cylindrically curved
rear surface 32, which is spaced from the conveyor belt 20 at
the adjacent roll 23, so that the outer edges of the slats 30
pass close to the concave surface 32 as the slats 30 pass
between the concave surface 32 and the roll 23. The conveyor
belt 20 is driven by an hydraulic motor 33 connected to the roll
21.
The hopper 19 is located above a pair of primary
crusher rolls 35 and 36 which each have a length of thirty-six
inches and a dia~eter of thirty inches. The primary crusher
roll 36 is rotatably mounted on shaft 37 journalled, at opposite
ends of the primary crusher roll 36, in a pair of fixed
pedestals 37, so that the axis of rotation of the primary
crusher roll 36 is fixed relative to the chassis 10. The
primary crusher roll 35, however, is mounted on a shaft 39
journalled in pedestals 40, which are mounted on a slide 41,
which in turn is slidably supported on the chassis 10, and a
hydraulic piston and cylinder device 42 is provided for
displacing the shaft 39, and therewith the primary crusher roll
35, to and fro in the horizontal direction, as viewed in Figure
1, relative to the primary crusher roll 36 for thereby adjusting
the spacing between the primary crusher rolls 35 and 36.
, ~
- 6 -
Below the crusher rolls 35 and 36 there is provided a
lower primary bin or hopper 43, which discharges onto an
underlying endless conveyor belt 44 running around a pair of
conveyor rolls 45 and 46. A pair of upwardly and rearwardly
inclined endless conveyors, indicated generally by reference
numerals 48 and 49, extend from the roll 46 to a discharge
position indicated generally by reference numeral 50, above one
end of a downwardly and rearwardly inclined vibrator screen
51,the endless conveyors 48 and 49 being driven by-hydraulic
motors 52 and 53 respectively.
The vibratory screen 51 is located above a vibrating
screen bin or hopper 55, the lower end of which discharges onto
a secondary conveyor belt 57 running around rolls 58 and 59 and
driven by an hydraulic motor 60. At the rear of the vibratory
screen 51, there is provided an upper secondary funnel 60,
which guides material from the vibratory screen 51 into the gap
between a pair of secondary crusher rolls 61 and 62. The
secondary crusher rolls 61 and 62 each have a length of thirty
inches and a diameter of twenty four inches.
The secondary crusher roll 61 is rotatably mounted on a
shaft 63 having a fixed axis, while the secondary crusher roll
62 is rotatably mounted on a shaft 64 which can be displaced
horizontally to and fro by means of a piston and cylinder device
65, in a manner and arrangement which are similar to that of the
primary crusher roll 35 and which are therefore not described in
greater detail. A lower secondary bin or hopper 67 is provided
~ J,~,
~2g~
below the secondary crusher rolls ~1 and 62 for receiving
crushed material from the secondary crusher rolls 61 and 62 and
for discharging the material onto the secondary conveyor belt 57.
An upwardly and rearwardly inclined discharge conveyor,
indicated generally by reference 70 is provided at the rear of
the crusher, and comprises an endless belt 71 running around
conveyor rolls 72 and 73 and driven by an hydraulic motor 74,
this discharge conveyor receiving and discharging mater~al from
the secondary conveyor 57. As can be seen fxom Figure 2, the
discharge conveyor 70 is inclined laterally of ~he longitudinal
axis of the crusher.
The rate of discharge of material from the hopper 19 to
the primary crusher rolls 35 and 36 may be regulated by means of
a part of a rear wall thereof which is pivoted about a pivot 76
to form a flap 77, shown in broken lines in Figure 1. The flap
77 is also ef~ective to break up any clogging of the primary
rolls. The flap 77 can be caused to pivot across the interior
of the primary hopper 19, by means of an hydraulic piston and
cylinder device 78 which is connected to the flap 77 through a
pin 79 that is slideable along the rear surface of the flap 77
within the embrace of a retaining bracket 80.
The tracks 15 are pivoted to the support structure 14
pivoted about a vertical axis, and also connected thereto by
means of a steering mechanism, for pivoting movement relative to
the chassis 10 for steering the tracks 15 and thus for steering
the crusher during its advance.
~ ; ~ 8 -
~2C~
Thus~ as shown in Figures 3 and 4, the front tracks 15
are mounted on a sub-chassis 90 provided with a :Laterally
projecting flange 91, the sub-chassis 90 being pivoted relative
to the main chassis 10 and connected thereto by means of a
steering hydraulic piston and cylinder device 92, which is
pivotally connected at opposite ends thereof to the chassis 10
and sub-chassis 90.
A motor 82 (Figure 2) mounted on the crusher chassis
toward the rear is provided for propelling the crusher along the
ground by dri~ing the ndless tracks 11. The top surface of the
pick-up blade 18 is upwardly and rearwardly inclined, while its
rear surface 32 is concave, as can be seen in Figure 1.
The pick-up blade assembly 18 is illustrated in greater
detail in Figures S and 6 and has a blade 96 which is pivotally
connected to the front of the pick up elevator 17 by means of a
horizontal pivot shaft 97, a pair of hydraulic piston and
cylinder devices 98, of which only one is shown in Figure 5,
being connected between opposite ends of the pick-up blade 96
and the elevator side walls front wall portions 85 and 86 for
effecting vertical pivotal adjustment of the pick-up blade 96.
Pick-up teeth 100 are spaced apart horizontally along the
pick-up blade 96 and removably secured thereto by respective
vertical bolts 101. Each tooth 100 is provided with a
replaceable cover 10~, which replaced when worn and for this
purpose is removably secured to the respective tooth 100 by a
horizontal bolt 103.
~Z~6~i~
As can best be seen from Figure 2, the pick-up elevator
side walls 25 and 26 include forwardly and laterally outwardly
inclined front wall portions 85 and 86 extending to opposite
sides of the pick-up blade 18 and also extendling downwa~dly to a
bottom wall 87 to direct the picked-up materi.al on to the
conveyor.
Referring to Figures 1, 7 and 8 a hydraulic piston and
cylinder device 88 for vertical adjustment of the elevator 70 is
connected between a unversal joint 88a mounted on the rear end
of the crusher and a universal joint 88b connected by struts 89
to the elevator 70 for vertical adjustment of the elevator 70.
The pick-up elevator 17 is mounted on the front end of
the chassis 10 by a pivot 93 for pivotal movement in a vertical
plane, and a further piston and cylinder device 94 is connected
between the chassis 10 and the pick-up elevator 17 for adjusting
the inclination of the latter.
Referring now to Figures 1 and 7, it will be seen that
an hyd.raulic piston and cylinder device 105 is connected between
a universal joint 105a, which is mounted on the rear end of the
crusher at a position laterally offset from the front end of the
elevator 70, and a universal joint 105a, which is mounted on one
side o the elevator 70, the hydraulic piston and cylinder
device 105 serving to effect pivotal to and fro horizontal
adju tment of the elevator 70.
The mounting arrangement illustrated in Figures 9 and
10 is provided to enable the vertical and horizontal pivotal
~ :~ O
~.~
adjustment of the elevator 70, this arrangement connecting the
front, lower end of the elevator 70 to the rear end of the
crusher~ The arrangement comprises a support member 106 mounted
on the rear of the crusher and projecting rearwardly, a pair of
vertically spaced projections 107 on the support member 106, and
a vertical pivot shaft 108 journalled in the projections 107.
An intermediate member 110 has a rear projection 111 through
which the pivot shaft 108 extends, and a pair of rearwardly
projecting, horizontally spaced arms 112. A horizontal pivot
shaft 113 extends through the arms 112 and through a lower,
front end roil 114 of the elevator 70 to allow vertical pivotal
movem~nt of the elevator 70 about the axis of the shaft 113.
Thus, this mounting arrangement provides a universal pivot
connection between the elevator 70 and the crusher.
lS The hydraulic circuit of the crusher is shown in Figure
11 and is powered by a diesel motor 120, which drives hydraulic
pumps 121a through 121i. The~e pumps are connected to the
various hydraulic motors and piston and cylinder devices, as
described below, through valves ~not shown~ incorporated in a
control unit 122, for manual control o the hydraulic circuit by
an operator as will be readily apparent to those skilled in the
art. The pumps draw their hydraulic fluid from a reservoir 130,
the fluid being returned from the motors and cylinders to
reservoirs 131 and 132 and thence through return lines 133 and
134 to the reservoir 130.
lZ~L6~
The hydraulic pumps 121a - 121i power hydraulic motors
and piston and cylinder devices for driving the components of
the crusher as follows:-
HYDR~UI,IC E~YDRAULIC MOTORS/S COMPO~ENT
MOTOR PISTO~ & CYLINDER
-
DEVICE/S
121a Motors 124~ 12S Secondary rolls 61, 62
121b Cylinder 65 Secondary rolls 61, 62
Motor 60 Secondary conveyor 57
121c Motors 126 Tracks 11
121d Motor 74 Conveyor 70
Cylinder 88 Conveyor 70
Cylinder 105 Conveyor 70
121e Motors 52 & 53 Conveyor 50
~5 Motor 127 Vibratory screen 51
}21f Cylinders 98 Pick-up blade 96
Motor 33 Conveyor 17
Cylinder 92 Track 15
121g Cylinder 94 Conveyor 17
Motor 123 Track 15
121h Cylinder 78 Flap 77
Cylinders 42 Primary rolls 35, 36
121i Motors 128, 129 Primary rolls 35, 36
In operation of the above-described crusher, the entire
crusher is advanced forwardly by the driving of the endless
tracXs 11, the forward advance being steered by means of the
tracX 15.
12 -
6~6
A bituminous pavement is pra-ripped into large lumps or
pieces by employment of a ripping tooth mounted on a bulldo~er
that rips the pavement longitudinally a number of (e.g. four or
five) times along parallel lines, these lumps or pieces being
picked up from the ground by forcing of the pick-up blade 18
along the interface of the pavement and the granular base course
as a result of the forward advance of the crusher. A
cementitious pavement layer would require more vigorous
pre breaking, as will be apparent to those skilled-in the art.
The pavement material pieces lifted over the pick-up
blade 18 in this way fall, at the rear of the pick-up blade 18,
onto the upper run of the endless conveyor belt 20 and are
carried upwardly by the slats 30 to be discharged from the
pick-up elevator 17 into the upper primary hopper 19. Any
granular base material picked-up with the pieces falls through
the openings 28 in the conveyor belt 20 to return to the ground,
and is thus not included in the final product discharged from
the crusher.
The pavement pieces fall from the hopper 19, at a rate
determined by the speed of advance of the crusher, between the
primary crusher rolls 35 and 35, which are adjusted to provide a
spacing between them somewhat smaller than the pavement depth
and thereby provide a primary crushing operation. ~he flap 77
is adjusted to restrict the throughput of the material through
the hopper, if and as necessary, to avoid clogging of the
primary crusher rolls 35 and 36. The primary crusher rolls 35
and 36 are set at the required spacing~ by adjustment of the
hydraulic piston and cy1inder device 42, as described above.
~ 13 ~
From the primary crusher rolls 35 and 36, the material
is directed by the lower primary hopper 43 onto the primary
conveyor belt 44, and i5 conveyed thereby and by the conveyors
48 and 49 onto the vibratory screan 51. The vibratory screen 51
5 has 1~1/2 inch openings and an adjustable slope, Consequently,
material smaller than 1 1/2 inches passes through the screen and
drops through the vibratcry screen hoppPr 55 onto the secondary
conveyor belt 57. Ovesize pieces of material, larger than L-1/2
inches, passes over the screen 51 and are deposited into the
upper secondary funnel 66 and are discharged thereby to pass
between the secondary crusher rolls 61 and 62. The spacing of
the secondary crusher rolls 61 and 62 is set as described above
so that the material passing therethrough i9 crushed to a size
less than l-l/2 inches, and this crushed material is received by
the lower secondary hopper 67 arld deposited onto the secondary
conveyor belt 57.
The material from the secondary conveyor belt 57 is
elevated by the discharge elevator 70 and discharged into a
truck (not shown) travelling with the crusher. To facilitate
the cooperation of the crusher with the truck, the position of
the discharge elevator 70 can be adjusted by means of the
hydraulic piston and cylinder devices 88 and 105, as described
above. In the case of a bituminous pavement the resultant
material is carried by the trucXs to an asphalt plant, where it
25 i5 recycled in hot mixed asphalt pavement material. The
material resulting from the crushing of a cementitious pavement
can be used as an aggregate in further construction.
14 -
~.
