U.S. patent number RE35,432 [Application Number 08/401,366] was granted by the patent office on 1997-01-28 for demolition tool for a hydraulic excavator.
This patent grant is currently assigned to LaBounty Manufacturing Co.. Invention is credited to Kenneth R. LaBounty, Roy E. LaBounty.
United States Patent |
RE35,432 |
LaBounty , et al. |
January 28, 1997 |
Demolition tool for a hydraulic excavator
Abstract
A demolition tool for attachment to the boom structure and
hydraulic system of a hydraulic excavator having a pair of jaws
pivotally connected together as to be mountable on the frame of the
tool by a movable pin so that the jaws may be placed with other
jaws having other forms of demolition characteristics. The jaws may
be a shear for steel or other structural material, including
concrete, and the jaws may be a concrete crusher, a rock or coral
breaker, a wood shear, a plate shear, or other form of demolition
device. Both jaws are swingable and independently swingable,
operated by a common manifold supplying hydraulic fluid to the
cylinders. The jaws swing through operational arcs and are arranged
so that the direction of thrust from the cylinders is tangential to
the pin connecting the cylinders to the jaws at a location
intermediate the ends of the operational arcs.
Inventors: |
LaBounty; Roy E. (Two Harbors,
MN), LaBounty; Kenneth R. (Two Harbors, MN) |
Assignee: |
LaBounty Manufacturing Co. (Two
Harbors, MN)
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Family
ID: |
23791942 |
Appl.
No.: |
08/401,366 |
Filed: |
March 9, 1995 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
451377 |
Dec 15, 1989 |
05060378 |
Oct 29, 1991 |
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Current U.S.
Class: |
30/134;
30/92 |
Current CPC
Class: |
E04G
23/082 (20130101); E02F 3/965 (20130101); E04G
23/08 (20130101); E02F 3/3681 (20130101); E01C
23/122 (20130101); Y10T 83/9447 (20150401); E04G
2023/086 (20130101) |
Current International
Class: |
E04G
23/08 (20060101); E01C 23/00 (20060101); E01C
23/12 (20060101); E02F 3/04 (20060101); E02F
3/96 (20060101); E02F 3/36 (20060101); B23D
017/06 () |
Field of
Search: |
;30/134,92,180,228
;72/453.16,453.2 ;83/694 ;91/229 ;137/633 ;251/116 ;241/101.72 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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28668 |
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Jul 1975 |
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CL |
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31141 |
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Sep 1979 |
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CL |
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36991 |
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May 1989 |
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CL |
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36487 |
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Jul 1989 |
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CL |
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0218899 |
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Apr 1987 |
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EP |
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8526390 |
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Dec 1985 |
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DE |
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3618191 |
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Dec 1987 |
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DE |
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0205349 |
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Nov 1985 |
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NZ |
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0203534 |
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Apr 1986 |
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NZ |
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2122125 |
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Jan 1984 |
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GB |
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Other References
Geith Brochure, four pages, LaBounty Catalog, pp. 3, 5, 6,
9-14..
|
Primary Examiner: Watts; Douglas D.
Attorney, Agent or Firm: Pepe & Hazard
Claims
I claim:
1. A heavy-duty demolition tool for attachment to the boom and
hydraulic system of a hydraulic excavator, comprising:
a frame mountable on the boom structure,
a pair of demolition jaws having pivot means connecting the jaws to
each other and to the frame means, the jaws being swingable through
predetermined operational arcs between open and closed positions,
.Iadd.said pivot means including coupling means coupling said jaws
and enabling pivotal motion thereof about a common axis relative to
said frame and relative to each other and maintaining said jaws in
assembly with each other when said jaws are dismounted as a unitary
assembly from said frame, .Iaddend.and
a pair of juxtaposed hydraulic cylinders mounted on the frame means
and connectable to the hydraulic system of the excavator, each of
the cylinders having a pivotal connection to a respective jaw, and
the hydraulic cylinders being extensible and retractable to move
the pivotal connections through such operational arc which are
nearly bisected by radii which are normal to the directions of
extension and retraction of the cylinders.
2. A heavy-duty demolition tool for attachment to the boom
structure and hydraulic system of a hydraulic excavator,
comprising:
a frame means mountable on the boom structure,
a pair of demolition jaws pivotally connected to the frame means,
each of the jaws being swingable through an operational arc from an
open position at one end of the arc wherein the jaws are widely
spaced from each other to receive a large workpiece between the
jaws, and to a closed position at a second end of the arc wherein
the jaws have been brought together, .Iadd.said jaws being
pivotably supported on said frame by pivot means including coupling
means coupling said jaws and enabling pivotal motion thereof about
a common axis relative to said frame and relative to each other and
maintaining said jaws in assembly with each other when said jaws
are dismounted as a unitary assembly from said frame, .Iaddend.
extensible and retractable means producing substantially linear
thrust and having a pair of thrust bearings each connected to a
respective jaw to swing therewith through said operational arc, the
direction of thrust at each bearing being substantially tangential
to the arc of the bearing at a location approximately midway,
between the ends of the arc, whereby to move both jaws toward
closed position to demolish a workpiece.
3. A heavy-duty demolition tool for attachment to the boom
structure and hydraulic system of a hydraulic excavator,
comprising:
a frame means comprising rigid mounting portions mountable on the
boom structure,
a pair of demolition jaws having pivot means connecting the jaws to
each other and to the frame means, both of the jaws being swingable
relative to the frame and through predetermined operational arcs
and the jaws having workpiece engaging portions swingable between
open and closed positions as the jaws move through the operational
arcs, .Iadd.said pivot means including coupling means coupling said
jaws and enabling pivotal motion thereof about a common axis
relative to said frame and relative to each other and maintaining
said jaws in assembly with each other when said jaws are dismounted
as a unitary assembly from said frame, .Iaddend.
and extensible and retractable means producing substantially linear
thrusts and having a pair of thrust bearings each connected to a
respective jaw to swing therewith through said operational arc, the
force at the workpiece engaging portions of the jaws being
substantially the same as the total thrust applied at the bearings
throughout the operational arcs of both jaws.
4. A heavy-duty demolition tool according to claim 3 and the thrust
bearing of each jaw being located on a radius from the pivot means
of the jaw and in relation to the extension and retraction means so
that the thrust is directed substantially normal to the radius
throughout the operational arc.
5. A heavy-duty demolition tool according to claim 3 and the
direction of thrust on each jaw substantially maximizing force
available at the workpiece engaging portion of each jaw.
6. A heavy-duty demolition tool according to claim 3, and including
a removable mounting pin defining a single axis of swinging for
both jaws and demountably connecting the demolition jaws onto the
frame means to facilitate replacement of the jaws.
7. A heavy-duty demolition tool according to claim 6 and a hollow
connector pin mounting the jaws to each other and preventing
separation thereof, the connector pin receiving said removable
mounting pin therethrough and maintaining the jaws in predetermined
relation to each other as the mounting pin is removed for replacing
the jaws.
8. A heavy-duty mobile demolition tool for attachment to the boom
structure and hydraulic system of a power implement, comprising
frame means mountable on the boom structure and having a pair of
rigid frame plates confronting each other in spaced relation, the
plates having front end portions with aligned pin openings
therethrough,
a pair of heavy-duty individually swingable workpiece demolishing
jaws having mounting portions disposed between the frame plates,
the mounting portions having pin openings therethrough,
a removable mounting pivot pin extending through the pin openings
of the frame plates and jaws, the pivot pin being removable for
replacing the jaws,
and a hollow connector pin securing the two jaws together but
permitting relative swinging thereof, the hollow connector pin
receiving said removable mounting pin therethrough for demountably
connecting the jaws to the frame means while maintaining the jaws
in assembly with each other.
9. A heavy-duty mobile demolition tool according to claim 8 wherein
said jaws swing through operational arcs between open and closed
positions, extensible and retractable means connected between the
frame means and said jaws by thrust bearings which swing with the
jaws through such operational arcs, the extensible and retractable
means extending in directions tangential to the operational arcs at
positions intermediate the ends of said operational arcs.
10. A heavy-duty demolition tool for attachment to the boom
structure and hydraulic system of a power implement,
comprising:
a frame mountable on the boom structure,
a pair of heavy-duty workpiece demolishing jaws comprising mounting
portions,
and jaw mounting means mounting both jaws for swinging about one
.Iadd.common .Iaddend.axis relative to the frame and relative to
each other and comprising a mounting pin portion removably mounting
the jaws on the frame, and also comprising a rotatable connector
portion .Iadd.through which said mounting pin portion extends, said
jaw mounting means enabling pivotal motion of said jaws about said
common axis relative to said frame and coupling said jaws for
movement relative to each other about said common axis, said
connector portion .Iaddend.retaining the jaws together
independently of the frame .Iadd.to enable said jaws and connector
portion to be assembled on or removed from said frame as a unitary
assembly upon insertion or removal of said mounting pin portion
therefrom. .Iaddend.
11. A heavy-duty demolition tool according to claim 10 wherein the
connector portion extends through the mounting portions of both
jaws and permits swinging of the jaws relative to each other.
12. A heavy-duty demolition tool according to claim 10 wherein the
connector portion and the pin portion extend concentrically through
the mounting portions of the jaws, the frame comprising a pin
opening removably receiving the pin portion.
13. A heavy-duty demolition tool according to claim 12 wherein the
connector portion rotatably mounts the mounting portions of both
jaws and the pin portion extends rotatably and concentrically
through the connector portion.
14. A heavy-duty demolition tool for attachment to the boom
structure and hydraulic system of a hydraulic excavator,
comprising:
an elongate frame comprising a rear portion attachable to the boom
structure and also comprising a front portion,
a pair of heavy-duty workpiece demolishing jaws comprising mounting
portions demountably attached to the front portion of the frame and
mounting both jaws for swinging about a single axis relative to the
frame and relative to each other between open and closed positions
.Iadd.said mounting portions being pivotably mounted on said frame
by pivot means including coupling means coupling said jaws and
enabling pivotal motion thereof about a common axis relative to
said frame and relative to each other and maintaining said jaws in
assembly with each other when said jaws are dismounted as a unitary
assembly from said frame, .Iaddend.
and a pair of extendable and retractable hydraulic cylinders
extending along the elongate frame and comprising mounting pivots
on the rear portion of the frame and also comprising connection
portions pivotally connected to the portions of the jaws adjacent
to the front portion of the frame, and cylinders extending in a
forward direction and retracting to swing the jaws through an
operational arc about said single axis between open and closed
positions.
15. A heavy-duty demolition tool according to claim 14 wherein
.Iadd.said coupling means of said pivot means for .Iaddend.the
mounting portions of the jaws comprise a .Iadd.hollow
.Iaddend.connector portion retaining the jaws together
independently of the frame when demounted from the frame.
16. A-heavy-duty demolition tool according to claim 15 wherein
.Iadd.said pivot means for .Iaddend.the mounting portions of the
jaws .[.comprise.]. .Iadd.include .Iaddend.a removable pin
.Iadd.extending through said hollow connector .Iaddend.portion
attaching the jaws to the frame.
17. A heavy-duty demolition tool according to claim 14 wherein said
connection portions also swing through said operational arc, the
direction of cylinder extension between the mounting pivots and the
connector portions being normal to radii from the single axis to
the connector portions when the connector portions are located
within an approximate midway portion between opposite end portions
of the operational arc, whereby to achieve nearly maximum thrust on
the jaws.
18. A heavy-duty demolition tool according to claim 17 wherein said
approximate midway portion comprises a range of 25.degree. to
30.degree. within the operational arc.
19. A heavy-duty demolition tool according to claim 17 wherein said
direction of cylinder extension and said radii are exactly normal
to each other at a location within said midway portion of the
operational arc.
Description
This invention relates to a heavy-duty mobile demolition tool as an
attachment for a hydraulic excavator.
BACKGROUND OF THE INVENTION
Heavy-duty shears have been developed for use in demolition work as
in the demolition of structures such as buildings. Although shears
were first intended to shear steel I-beams, pipes, columns and the
like, they have been found to be very useful in removing bridge
decks in highway rebuilding activity and in many other types of
demolition work. Such shears have been illustrated in a number of
U.S. patents, such as Labounty U.S. Pat. No. 4,519,135 and Ramun
U.S. Pat. No. 4,403,431.
However, other demolition attachments such as concrete crushers or
pulverizers, and heavy-duty wood or log shears have also been
devised for mounting on hydraulic excavators. See U.S. Pat. Nos.
4,838,493; 4,106,862; 4,515,524; 4,776,524; 4,872,264, and
copending application Ser. No. 254,145, filed Oct. 6, 1988.
SUMMARY OF THE INVENTION
An object of the invention is to provide, as an attachment for a
mobile power source such as a hydraulic excavator, a heavy-duty
mobile demolition tool which is capable of engaging and severing
workpieces to which nearly maximum force may have to be applied at
any of the wide range of stages in the severing process. For
instance, certain types of workpieces, such as rock or concrete,
may require that maximum demolition force be applied when the jaws
of the tool are nearly wide open; and for demolishing other types
of workpieces, such as in shearing steel, maximum demolition force
may have to be applied when the jaws are nearly closed.
A feature of the invention is providing the attachment with a jaw
driving cylinder in an arrangement wherein during extension of the
cylinder ram, the radius between the point of connection to the jaw
and the jaw pivot is oriented approximately normal to the direction
of extension of the cylinder when the cylinder ram is extended
about halfway between full extension and full retraction. The point
of connection between the ram of the cylinder and the jaw will
swing through an operational arc during a closing of the jaws; and
the direction of extension of the cylinder lies tangent to the
operational arc at a position approximately midway between the ends
of the operational arc or approximately midway between the
positions wherein the cylinder is fully retracted and fully
extended. This same driving arrangement is applied to both movable
jaws so that the jaws may be opened very widely and also fully
closed toward each other while swinging through a minimal
operational arc.
Another object of the invention is to provide in such a demolition
tool for a hydraulic excavator, the capability of engaging the
workpiece in such an attitude so that the bite of the tool will be
of nearly maximum size and so that the necessary demolition force
will be applied regardless of whether the boom of the excavator is
in exactly the optimum position. Accordingly, the high magnitudes
of strain and forces on the equipment will be borne by the
demolition tool rather than the boom structures of the
excavator.
A feature of the invention is mounting both demolition jaws to
swing independently of each other and driving the jaws to allow
staging of jaw movement as may be desirable, depending upon the
nature and shape of the workpiece being worked on. Preferably, the
hydraulic cylinders of both jaws are supplied with high pressure
hydraulic fluid from the same pressurized source and from a common
manifold. The fluid will flow to the cylinder wherein least
resistance is encountered, and if one demolition jaw first engages
a workpiece, such as a thick concrete slab, that jaw may remain
stationary while the other demolition jaw continues to swing.
Thereafter, when both demolition jaws are in engagement with the
workpiece, both jaws will apply demolishing force onto the
workpiece to produce severing as by crushing or otherwise.
Still another object of the invention is to provide an attachment
for the mobile power source which is readily convertible to any of
a multiplicity of heavy-duty demolition tools such as a heavy-duty
shear, a rock or coral breaker, a concrete crusher, a stump or log
shear, or a plate shear. By simply changing the jaws of the tool,
the attachment may serve numerous purposes.
Accordingly, a feature of the invention is an attachment having
connection to the demolition jaws by a readily removable pivot pin
which provides the only connection between the frame of the
attachment and the jaws. The jaws may also be pivotally
interconnected to remain together when removed from the attachment
frame. Two separate pins connect the rams of the hydraulic
cylinders to the jaws and are readily removable.
It will be seen in the drawings that the demolition jaws may take
any of various forms. The demolition may take any of a number of
different forms as indicated previously. Demolition usually, but
not always, involves severing the workpiece in one way or another.
The severing may be effected by shearing, cutting, cracking,
breaking, crushing, sundering, rending, wrenching apart, etc.,
depending upon the nature and size and shape of the workpiece and
the demolition jaws of the tool.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevation view of the attachment shown connected to
the boom structure and hydraulic system of a hydraulic
excavator.
FIG. 1a is a diagrammatic view illustrating the extension and
retraction of the cylinders and the swinging movement of the
jaws.
FIG. 2 illustrates the demolition jaws in partly closed condition
and grouping a workpiece.
FIG. 3 is another view illustrating the functioning of the jaws in
a different attitude as compared to that illustrated in FIG. 2.
FIG. 4 illustrates the jaws in fully closed condition.
FIG. 5 is a perspective view showing the principal components of
the shear or demolition tool illustrated in FIGS. 1-4.
FIG. 6 is an elevation view of an alternate form of demolition jaws
alternately mountable upon the attachment frame.
FIG. 7 is a perspective view of the tool illustrated in FIG. 6.
FIG. 8 is an elevation view of a wood shear which may be readily
substituted for the jaws illustrated in FIG. 1.
FIG. 9 is a perspective view of the wood shear illustrated in FIG.
8.
FIG. 10 is an elevation view of a plate shear which may be
substituted in the attachment.
FIG. 11 is a detailed section view taken approximately at 11--11 of
FIG. 10,
FIG. 12 is an elevation view of an alternate set of demolition jaws
incorporating a rock or coral breaker and which may be substituted
in the attachment for the jaws illustrated in FIG. 1.
FIG. 13 is a detailed section view taken approximately at 13--13 of
FIG. 12.
FIG. 14 is a diagrammatic view showing the typical hydraulic
circuit for the cylinders of the operating tool illustrated in FIG.
1.
FIG. 15 is detailed section view through the pivot structure of the
attachment.
DETAILED SPECIFICATION
One form of the invention is illustrated in the drawings and is
described herein.
The demolition tool is indicated in general by numeral 10 and
comprises an attachment for a mobile power implement indicated in
general by numeral 11, of which the boom 12 is seen adjacent to the
main hydraulic cylinder 13 of the hydraulic excavator for
manipulating the demolition tool 10. The demolition tool 10 has a
frame means which is indicated in general by the numeral 14 and
which is tiltably mounted by a mounting pin 15 on the boom
structure 12 of the excavator. The frame means 14 may be tilted to
various angles by the hydraulic cylinder 13 which is connected to
the frame means by a connector pin 16 as to control the attitude of
the tool 10 in certain respects.
The frame means includes the mounting portion 17 which is connected
to the boom structure 12 and hydraulic cylinder 13; and also
includes a rotatable frame 18 which is connected to the frame 17
and is rotatable with respect to the frame 17 about a centerline or
axis of rotation indicated by the dashed line 19.
A hydraulic motor 20 is mounted on the frame portion 17 to operate
certain gearing for revolving the frame with respect to the frame
17 and with respect to the boom structure 12.
A cluster of hydraulic hoses or connections 21 is attached to the
hydraulic system of the hydraulic excavator 11, which system also
includes the cylinder 13 for operating the motor 20 to rotate the
frame portion 18 as desired. Of course, the controls for the
hydraulic system are in the cab of the excavator, to be controlled
by the operator
The tool 10 also includes a pair of demolition jaws 22 and 23 which
are mounted on the frame 18 by a single removable pivot pin 24
about which the jaws 22 and 23 swing. The jaws are operated by
extensible and retractable means in the form of hydraulic cylinders
28 and 26, the rams 27 of which are swingably connected by pins 28
and 29 and thrust bearings 30 and 31 to the connector portions 32
and 33 of the jaws 22 and 23. The jaws 22 and 23 constitute
heavy-duty shears as illustrated in FIGS. 1-5, and accordingly the
upper jaw 22 has shear edges 34 and 35 which extend obliquely to
each other at an obtuse angle and are defined by hardened steel
insert blocks 36 and 37 respectively. A hardened tip end block 38
is also provided on the tip end of the upper jaw 22.
Similarly, the swingable lower jaw 23 also has a shear blade 39
with shearing edges 40 and 41 oriented at oblique angles with
respect to each other and defined by hardened steel insert bars or
knives 42, 43 which are bolted to the shear blade 39 and are
replaceable. The lower jaw 23 also includes a guide blade 44
secured by a tie plate 45 to the lower shear blade 39 so as to be
rigidly connected to the lower shear blade. The guide blade 44 also
has a replaceable spacer or wear plate 46 bolted thereto adjacent
the outer end as to bear against the side of the upper shear blade
22.1 and hold all of the shearing edges 35, 36, 40, 41 in shearing
relation to each other. The top edge surface 47 of the guide blade
44 is recessed below the level of the edges 443, 41 of the lower
shear blade 39. As the cylinders 25, 26 are extended, the jaws 22,
23 swing through operational arcs from the fully open position
illustrated in FIG. 1 to the fully closed position illustrated in
FIG. 4. As the jaws swing through the operational arc, the tip ends
38, 45.1 swing from the full line positions illustrated in FIG. 1
to the dotted line positions illustrated in FIG. 1 and indicated by
the numerals 38a and 45.1a. During swinging of the jaws through the
operational arcs, the connector pins 28, 29 and their respective
thrust beatings 30, 31 by which the extendible rams 27 apply
demolition force onto the jaws, will swing to the dotted line
position 28a, 29a.
Cylinders 25, 26 are mounted on the frame plates 18.1 by removable
pivot pins 48, 49, the heads of which have radially extending keys
retained in keyways 51 as to prevent the pins 48, 49 from rotating,
but permitting removal of the pins by axially withdrawing them from
the frame and the ends of the cylinders, 25, 26.
As the cylinders 25, 26 extend and retract as to produce swinging
of the jaws 22, 23 through their operational arcs, the cylinders
25, 26 also swingably oscillate very slightly about the pivot pins
48, 49, thus permitting the connector pins 28, 29 to swing through
the operational arc about the center of pivot 24 as the jaws 22 are
swung between open and closed positions.
The relation between the jaws and the hydraulic cylinders, and the
pivot which mounts the jaws on the frame, is arranged as to cause
substantially maximum force or thrust to be supplied by the
cylinders 25, 26 to the jaws and to the workpiece-demolishing faces
of the jaws throughout substantially the entire operational arcs of
the jaws.
In FIG. 1a, the relation is illustrated diagrammatically to show
that the force supplied by the cylinders is maintained at nearly
maximum level throughout the entire operational arc. The points 28,
28a show the ends of the operational arc of the jaw 22 and the
cylinder 25 is retracted and extended. Similarly, the points 29,
29a show the retracted and extended positions of the lower jaw 23
as the cylinder 26 is retracted and extended to opposite ends of
the operational arc.
Maximum thrust from the cylinders 25 and 26 is applied to the jaws
22, 23 when the direction of extension of the cylinders 25, 26 from
the pivots 48, 49 and to the pivots 28, 29, have been extended
until the connector points 28, 29 are approximately midway betwen
the ends of the operational arc, and until the direction of
extension of the cylinders is tangent to the operational arc
subscribed by the pivots 28, 29; and when the direction of
extension, i.e., a straight line between the pivots 48 and 28 and
another straight line between the pivots 49 and 29 are oriented at
fight angles or normal to the radii 22.2, 23.2 between the the
pivot 24 and the pivots pins 28, 29, respectively. The position of
these radii 22.2, 23.2 in shifted position at the moment of maxium
thrust is shown in FIG. 1a by the dotted lines indicated by the
numerals 22.2a and 23.2a. At the moment of maximum thrust from the
cylinders 25, 26 the imaginary lines between pivots 48, 28.1 and 24
are at right angles to each other; and the pivots 49, 29.1 and 24
are at rights angles to each other. The points in FIG. 1a indicated
by numerals 28.1, 29.1 are on the operational arc followed by the
pins 28, 29.
While the size of the angle between the opposite ends of the
operational arc is not intended to be limiting according to this
invention, it has been found that the total operational arc of each
jaw may be in the range of 50.degree.; and from the location
wherein maximum thrust is exerted, the arc may be in the range of
25.degree. to 30.degree..
The cylinders 25 and 26 are preferably connected by common
manifolds 52, 53 to a reversing valve 54 which is preferably
located in the cab of the hydraulic excavator to be controlled by
the operator. The valve 54 is connected at one side 55 to a source
of pressure in the hydraulic system, such as a high pressure pump,
and is also connected at 56 to a hydraulic fluid return, such as a
resevoir, which is also a pan of the hydraulic system. Because the
hydraulic cylinders 25 and 26 are connected by the common manifolds
to the source of pressure and to the return duct, the jaws 22, 23
are free to turn at various angles with respect to the frame 18 and
with respect to each other as the jaws are closing. When the jaws
are in a fully open position as illustrated in FIG. 1, the valve 54
may be reversed as the tool 10 approaches a workpiece, such as the
concrete slab C illustrated in FIG. 2, and if the slab is oriented
substantially as illustrated, both jaws will be strung partially
through their operational arcs and may engage the workpiece C
approximately simultaneously. On the other hand, if the workpiece D
as illustrated in FIG. 3, which may be a concrete slab, is oriented
as illustrated, the lower jaw 23 may initially engage the workpiece
before the jaw 23 has had a chance to swing at all, or the lower
jaw 13 may swing through a small angle before it engages the
workpiece D. At this moment, the top jaw may still be in the
position illustrated in FIG. 1. Because the cylinders are connected
to a common manifold, the hydraulic fluid will flow to the area of
least resistance, and in this instance the concrete slab or
workpiece D may bear against the jaw 13 as to restrain it from
moving; and simultaneously, hydraulic fluid will flow into the
cylinder 25 as to swing the jaw 22 until the jaw engages the
workpiece. When both jaws have engaged the workpiece, the back
pressure in the two cylinders 25 and 26 is the same, and as
additional hydraulic fluid flows into the cylinders, pressure is
applied onto the workpiece to cause severing of it or crushing. The
shear blades will shear any reinforcing rods in the concrete slab
and this way the workpiece D will be demolished.
The idependently and freely swingable upper and lower jaws 22 of
the tool which may be in fully open position as the tool approaches
the workpiece, permit the jaws to orient themselves to the
orientation of the workpiece, and accordingly, the jaws will take a
full sized bite on the workpiece as to accomplish a substantial
amount of work with each cycle of operation of the demolition
tool.
Because the jaws are freely independently swingable with respect to
each other and with respect to the frame 18 of the tool, the
reactive forces from the jaws onto the frame of the tool 10 and
onto the boom structure 12 of the machine will be minimized, and at
the same time, the demolition jaws may take a maximum bite onto the
workpiece for severing or crushing portions of it.
The demolition jaws 22, 23 of the demolition tool 10 are readily
demountable as to be replaceable. The pivot pin 24 may be readily
removed from the jaws and frame, simply by sliding it out of the
jaws and adjacent frame plates 18.1. The pivot pins 2.8, 29 are
readily removable as to separate the jaws from the thrust bearings
30, 31 of the rams 27, thereby entirely freeing the jaws 22, 23 to
be replaced. Other forms of demolition jaws may be substituted for
the shears illustrated in FIGS. 1-5. In FIG. 6, the demolition jaws
22.10, 23.10 take the form of concrete crusher or pulveriser jaws
similar to those illustrated in U.S. Pat. No. 4,838,493. The
concrete crusher jaws include an array of points and protrusions 57
which may take a wide variety of shapes and arrangements, to apply
localized pressure at a multiplicity of locations on the concrete
workpiece and cause crushing of it into small chunks as to loosen
the reinforcing rods which may be salvaged for purposes other than
the concrete. The jaws 22.10 and 23.10 are secured together by a
hollow connector pin identical to the connector pin 58 by which the
jaws 22, 23 of the tool 10 are connected. FIG. 15 illustrates the
pivot construction of the jaws 22, 23 and the readily demountable
feature which utilizes the removable center pivot pin 24. The
removable pivot pin 24 extends entirely through the pivot structure
for the jaws 22, 23 and through the mounting hubs of the outside
frame plates 18.1. The head 59 on pin 24 has a radially projecting
key 60 projecting into and retained by a correspondingly shaped
keyway 61 on the outside of the adjacent frame plate which retains
the pin 24 against rotation relative to the frame plate. A
removable collar 62 retains the other end of the removable pin 24
stationary relative to the frame plates to prevent unintentional
removal of the pin. The collar 62 is demountably affixed to the
pivot pin 24 as by a retainer or key pin 63.
The hollow connector pin 58 is cylindrical and has a pair of
internal bronze bushings 64 to receive and bear against the
removable pivot pin 24 and allow the hollow connector 58 to revolve
on the stationary pin 24.
The upper swingable jaw 22 is press fit onto the outer periphery of
the connector pin 58. Accordingly, the upper jaw 22 has a central
opening 65 which tightly fits in a press fit onto the outer
periphery of the pin 58 so that the upper jaw 22 will not rotate
with respect to the pin 58, but is stationary, with the pin 58
which will turn as the upper jaw 22 turns.
Adjacent the hub portions of the upper jaw 22 are a pair of thrust
washers 66 which maintain spacing between the hub portions of the
upper jaw 22 and of the lower jaw 23.
The lower jaw 23 has a central opening 67 which receives bronze
bushings 68 therein. The bronze bushings 68 are mounted on the
outer periphery of the hollow pivot pin 58 and facilitate the lower
jaw 23 to rotate with respect to the pin 58. The bronze bushings 68
and the pivot pin 58 are clamped and retained together by a pair of
retainer caps 69 which are fastened to the hub portions of the
lower jaw 23 by cap screws 70.
Thrust washers 71 are provided between the retainer caps 69 and the
ends of the pivot pin 58. Additional thrust washers or spacers 72
are provided between the end caps or retainers 69 and the adjacent
hub portions of the frame plates 18.1.
The jaw assembly, including upper and lower demolition jaws 22, 23,
hollow pivot pin 58, end caps 69 and the detail bushings and
washers described, have a central opening 0 including the aligned
openings of all the assembled parts. The opening 0 removably
receives the pivot pin 24 which is supported by the frame plates
18.1
As seen in FIG. 4, the portions 22.3, 23.3 of the upper and lower
jaws receive the connector pins 28, 29 by which the rams 27 of
cylinders 25, 26 are connected to the jaws. The pins 28, 29 have
transversely projecting keys 28.1, 29.1 received into key ways of
retainers 22.4, 23.4 as to prevent pins 28, 29 from routing, but
allowing the pins to be readily removed. The pins are retained
against accidental removal by conventional collars or pins.
In FIGS. 6-12 other types of retainers 22.5, 23.5 are illustrated
for preventing pins 28, 29 from removal and from routing.
By this pivot construction, the pivot pin 24 is stationary with the
frame 18; the upper jaw 22 and pivot pin 58 turn on the central pin
24 as the cylinder 25 is extended and retracted; the lower jaw 23
and the bushings 67 and the end caps 69 turn on the pivot pin 58 as
the cylinder 26 is extended and retracted. In order to change jaws
on the tool 10, the pivot pins 28, 29 which connect the rams to the
jaws must be removed; and then the main pivot pin 24 will be
removed by simply removing the collar 62 and sliding the pin 24 out
of the jaws and adjacent frame plates 18.1.
Each of the other demolition tools illustrated in FIGS. 6-13 have a
similar mounting and pivot structure pin receiving opening 0, and
and each of the demolition jaws illustrated utilizes a hollow
connector pin 58 to hold the jaws together so that the jaws will
remain in assembly with each other when the jaws are to be replaced
on the tool 10.
As seen in FIGS. 6 and 7, the concrete crusher jaws have end caps
69.1 which are identical to the end caps 69 of FIG. 25 for
retaining the jaws and hollow pivot pin in assembly.
In FIGS. 8 and 9, another form of demolition jaws are illustrated
and in this case, the jaws 22.11 and 23.11 form a wood cutting
shear for handling big chunks of wood and stumps. These wood shear
jaws are substantially identical to those illustrated in co-pending
application Ser. No. 254,145, filed Oct. 6, 1988. Again, the jaws
22.11 and 23.11 are connected together so that they may be inserted
into the tool 10 to replace the jaws 22, 23, simply by inserting
the mounting pin 24 and connecting the pins 28, 29 for connecting
the hydraulic cylinder.
In FIGS. 10 and 11, a plate shear P is illustrated for attachment
to the tool and has a movable jaw 22.12 and a second jaw J which is
intended to be stationary and which is connected by a rigid link L
to replace one of the cylinders of the tool. The jaw 22.12 is
connected in the usual way to the other cylinder and the pivot
structure has an opening 0 to receive the pivot pin.
In FIGS. 12 and 13, the jaws 22.13 and 23.13 take the form of a
rock or coral breaker. These demolition jaws have an array of tips
or points which are staggered in relation to each other so that the
points will not directly confront each other as the jaws are closed
and accordingly, demolition force can be exerted against a large
rock or coral chunk as to cause breaking of it into smaller
pieces.
It will be seen that the present invention provides a single tool
as an attachment for a hydraulic excavator which facilitates the
mounting of a number of different types of replaceable jaws on the
attachment for performing various tasks as they may arise without
having to duplicate equipment. The attachment also applies neary
maximum demolition force from the cylinders to the demolition jaws
over substantially the full range of operational arcs of the jaws.
Accordingly, nearly maximum pressure may be applied onto the
workpiece when the jaws are wide open as well as when they are
nearly closed. Furthermore, because of the independently movable
jaws and the common manifolds of the hydraulic cylinders which
operate the jaws, the jaws will be free to swing at various angles
with respect to each other and with respect to the frame of the
attachment so that the jaws may be individually oriented at various
angles. Accordingly, maximum bite may be taken against the
workpiece being demolished and reactive force from the jaws to the
frame of the attachment is minimized.
The present invention may be embodied in other specific forms
without departing from the spirit or essential attributes thereof,
and it is therefore desired that the present embodiment be
considered in all respects as illustrative and not restrictive,
reference being made to the appended claims rather than to the
foregoing description to indicate the scope of the invention.
* * * * *