Note: Descriptions are shown in the official language in which they were submitted.
Indicator System for Couplers
TECHNICAL FIELD
[ow] This
invention relates to an indicator system, and more particularly to an
indicator system associated with coupler assemblies for earth-moving machinery
such
as excavators, back hoes, and loaders.
BACKGROUND
[002] Quick couplers have been used to couple and uncouple work tools or
implements (attachments) to the work arms/sticks of earth-moving machinery
such as
excavators, back hoes, and loaders. For example, a backhoe may use a variety
of
buckets of various widths and shapes that are suitable for different tasks. In
addition to
buckets, other implements such as pneumatic hammers, hole augers, grapples,
shears,
rippers and the like may be used with excavating machines.
[003] A potential danger with a quick coupler is that the coupler can fail
to hold the
attachment at one or more of the mounting points resulting in the attachment
either
falling off the coupler or swinging down from the coupler. The consequences of
such
failures can be injury to or death of someone in the vicinity of the earth
moving
machine.
[004] Whilst the operator of a earth moving machine is able to see and
confirm
engagement of the front portion of the coupler with the pin or boss of the
attachment,
the engagement of the rear pin or boss of the attachment is not visible to the
operator.
1005] In
some jurisdictions, safety regulations for quick couplers using a pin
grabber [a known coupler] require an operator to be able to verify at the
operator's
station that a pin grabber is fully engaged with the attachment in its working
position.
Verification may be by any combination of sensing, visual indication, or
visual check
during testing.
[006] Some
current systems for verifying engagement are prone to failure because
they are not robust enough to survive the environment which pin grabbers are
subject
to.
1
CA 3024639 2018-11-20
[007] In a known system a wedge pin indicator is mounted to the
engagement
wedge and contacts with the pin of the coupled attachment. The wedge pin
indicator is
connected via a semi-rigid cable to a signal mechanism. When the wedge pin
indicator
shifts, it shifts the signal mechanism to indicate engagement. The cable used
to shift
the mechanisms is subject to failure due to the harsh environment couplers are
used.
The cable can be torn off or kinked, rendering the indicator useless.
Additionally, the
return spring that resets the system is located in the wedge pin indicator. If
the cable is
severed while the indicator is in the engaged position, it will not reset on
its own. The
cables are also costly to replace.
[008] In another known system, the main coupling cylinder is relied upon to
shift
when the jaw engages, which in turn pushes a rod through the front plate of
the
chassis.
[009] This "Background" section is provided for background information
only. The
statements in this "Background" are not an admission that the subject matter
disclosed
in this "Background" section constitutes prior art to the present disclosure.
SUMMARY
[0010] The present invention provides an improved indicator system for
pin grabber
couplers. In one aspect the invention utilizes a pin indicator housing and a
signal
component housing connected via a hydraulic line using fluid (hydraulic oil,
brake fluid,
etc.). A hydraulic line is stronger, more flexible and resistant to kinks and
is easier to
source when a filed failure in occurs.
[0011] The signal component incorporates a return spring that allows the
system to
reset if the connection between the signal and pin indicator is severed. This
provides
another safety element to the system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The present invention may be further understood by reference to
the
description of the embodiments, taken in conjunction with the accompanying
drawings,
in which:
[0013] Figure 1 is a perspective view of one embodiment of a pin grabber
having a
signal component and a pin indicator component according to the present
disclosure.
2
CA 3024639 2018-11-20
[0014] Figure 2 is a diagrammatic view of a signal component and a pin
indicator
with a hydraulic line between them. A coupler attachment pin is also shown for
illustrative purposes.
[0015] Figure 3 is an exploded view of a signal component and a pin
indicator
illustrating the component parts thereof.
[0016] Figure 4 is a diagrammatic side view depicting the signal
component and pin
indicator when the signal component is engaged with a coupler pin [coupler is
not
shown].
[0017] Figure 5 is a cross-section view of Figure 4 at section C-C.
[0018] Figure 6 is a diagrammatic side view depicting the signal component
and pin
indicator when the signal component is not engaged with the coupler pin.
[0019] Figure 7 is a cross-section view of Figure 5 at section D-D.
[0020] Figure 8 is an angle bucket without attachment pins in the
attachment
hookup.
[0021] Figure 9 is an angle bucket with attachment pins in attachment
hookup.
[0022] Figure 10 is a perspective view of a pin grabber coupler.
[0023] Figure 11 is a top perspective view of the pin grabber coupler of
Figure 10.
[0024] Figure 12 is a side perspective view of the pin grabber engaged
with the
angle bucket of Figure 8.
[0025] Figure 13 illustrates the hydraulic fluid housing mounted on the pin
grabber
coupler.
[0026] Figure 14 is a side view of the signal component mounted on the
pin grabber
coupler.
[0027] Figure 15 is a top perspective view of the signal component
mounted on the
pin grabber coupler.
[0028] Figure 16 is a top perspective view of the pin indicator
component mounted
on the pin grabber coupler.
[0029] Figure 17 is a top perspective view of the pin indicator
component mounted
on the pin grabber coupler before contact with an attachment pin.
3
CA 3024639 2018-11-20
[0030] Figure 18 is a top perspective view of the pin indicator
component mounted
on the pin grabber coupler when the pin indicator component pin is in first
contact with
an attachment pin.
[0031] Figure 19 is a top perspective view of the pin indicator
component mounted
on the pin grabber coupler when the pin indicator component pin is compressed
by an
engaged attachment pin.
[0032] Figure 20 is a close-up view of the of the signal component
mounted on the
pin grabber coupler before coupler engagement.
[0033] Figure 21 is a close-up view of the of the signal component
housing mounted
on the pin grabber coupler with the signal pin extended
[0034] Figure 22 is a schematic of another embodiment of a pin grabber
coupler
engaged with an implement wherein the hydraulic pin signal is transformed to
an
electrical signal.
[0035] Figure 23 is a perspective view of a further embodiment of a
signal
component and a pin indicator component mounted on a wedge type coupler.
DETAILED DESCRIPTION
[0036] The description, which follows, and the embodiments described
therein, are
provided by way of illustration of an example, or examples of particular
embodiments of
principles and aspects of the present invention. These examples are provided
for the
purposes of explanation, and not of limitation, of those principles and of the
invention. In
the description that follows, like parts are marked throughout the
specification and the
drawings with the same respective reference numerals. As used herein, the term
"and/or" includes any and all combinations of one or more of the associated
listed
items.
[0037] The terminology used herein is for the purpose of describing
particular
embodiments only and is not intended to be limiting of the invention. As used
herein,
the singular forms "a", "an" and "the" are intended to include the plural
forms as well,
unless the context clearly indicates otherwise. It will be further understood
that the
terms "comprises" and/or "comprising", when used in this specification,
specify the
presence of stated features, integers, steps, operations, elements, and/or
components,
4
CA 3024639 2018-11-20
but do not preclude the presence or addition of one or more other features,
integers,
steps, operations, elements, components, and/or groups thereof.
[0038] Unless otherwise defined, all terms (including technical and
scientific terms)
used herein have the same meaning as commonly understood by one of ordinary
skill
in the art to which this invention belongs. It will be further understood that
terms, such
as those defined in commonly used dictionaries, should be interpreted as
having a
meaning that is consistent with their meaning in the context of the relevant
art and will
not be interpreted in an idealized or overly formal sense unless expressly so
defined
herein.
[0039] Figure 1 illustrates a pin grabber 10 engaged with a first
attachment pin 15 of
an attachment [not shown] locked in the grabber front hook portion 20 and a
second
attachment pin 25 of the attachment [not shown] in the grabber rear recess
portion 30.
The indicator system of the present invention comprises a hydraulically
operated signal
component 45 and a hydraulically operated pin indicator component 35 connected
by a
hydraulic line 55 there between.
[0040] As shown in Figures 3, 5 and 7, the signal component 45 comprises
a main
body 60 which houses all of the hydraulic components thereof. A piston 65 with
seals at
one end slides over a seal 80 on the tip of a packing gland 75. A hydraulic
plug 70
threads into the smaller end of the piston 65. The plug is used to fill the
system with
hydraulic fluid, and bleed air from it. A spring 95 surrounds the outer
surface of piston
65. The packing gland 75 screws into a threaded end of the main body 60. A
small port
85 is provided through the packing gland threaded end. The piston has seals at
one
end thereof. At the seal end there are several orifices 95 for expelling air
from the main
body 60 through a port 100 at the threaded end of the packing gland end, when
the
piston moves back and forth during operation. The port may have a sintered
bronze
case breather installed into it, which acts as a filter as air is passed from
the within the
signal component to atmosphere.
[0041] In operation, hydraulic fluid is pressurized and forced through
the hydraulic
line 55 between the pin indicator 35 and the signal components 45. The
hydraulic fluid
causes the piston 65 to move from a first position within the main body 60 to
a second
position wherein the piston projects outside the opposite end of the main body
by
several inches, approximately 3.25 inches [82.55 mm]. When hydraulic pressure
is
5
CA 3024639 2018-11-20
reduced/lost, the spring 95 acts on the piston 65 to move it from its second
position to
its first position. The projected piston provides a visual indication to the
operator that the
pin grabber is fully engaged with and locked to the attachment pins. The
signal
component is mounted to a plate 50 affixed to the pin grabber. Alternatively,
the signal
component may be mounted to the excavator arm/stick.
[0042] As shown in Figures 3, 5 and 7, the pin indicator component 35
comprises a
housing 120 having a threaded indicator packing gland 125 at a first end that
retains a
moveable plunger 110 disposed within the housing 120. The plunger 110 is
provided
with a seal 115 at the end proximate the threaded indicator packing gland. The
plunger
allows the system to build hydraulic pressure as the plunger compresses. The
pin
indicator component is attached to a plunger mount plate 40 via a wedge pin
130
inserted into the pin hole of the pin grabber. The wedge pin 130 may be welded
to the
mount plate 40. The mount plate is also retained to the pin grabber by a bolt
through a
hole on the mount plate.
[0043] In operation, the end of the plunger 110 is compressed by contact
from an
attachment pin 25. Compression of the plunger 110 pressurizes hydraulic fluid
within
the pin indicator component. When compressed, the plunger 110 travels
approximately
2 inches [50.8 mm] from a first extended position. The fluid flows through the
packing
gland end of the pin indicator component through a hydraulic line into the
packing gland
end of the signal component. As the hydraulic fluid pressurizes within the
signal
component 45, the piston 65 moves from a first position within the main body
60 to a
second position wherein the piston 65 projects outside the opposite end of the
main
body by approximately 3.25 inches [82.55 mm]. Where hydraulic fluid is an
incompressible fluid, the linear movement between the plunger 110 of the pin
indicator
35 and the piston 65 of the signal component 45 sees no volumetric loss. The
bore of
the signal piston is 20 mm [0.787 inch] which is slightly less than the
diameter of the pin
indicator piston which is 25.4 mm [1.0 inch]. This results in a longer linear
transition of
the signal piston than the pin plunger.
[0044] Figure 22 depicts another embodiment of the invention. In this
embodiment,
the hydraulic pin indicator connects to an accumulator and electric sensor.
The
electrical sensor transmits an electrical signal to the excavator cab to a
visual (and/or
6
CA 3024639 2018-11-20
acoustic) signal display that confirms to the operator that the pin grabber is
connected
to and locked with the attachment pins.
[0045] Figure 23 depicts another embodiment of the invention wherein the
coupler is
a wedge coupler. In this embodiment, the hydraulic line from the pin indicator
is
disposed adjacent a wedge locking mechanism that locks the wedge coupler to
the
attachment. The movement of the wedge locking mechanism against the pin
plunger
compresses the plunger and results in the pressurization and movement of
hydraulic
fluid into the signal component as described above in the first embodiment.
[0046] While the principles of the invention have been shown and
described in
connection with specific embodiments, it is to be understood that such
embodiments
are by way of example and are not limiting. As is evident from the foregoing
description,
certain aspects of the present invention are not limited by the particular
details of the
invention illustrated in the drawings.
[0047] The terms "having", "comprising" and "including" and similar
terms as used in
the foregoing specification are used in the sense of "optional" or "may
include" and not
as "required". Many changes, modifications, variations and other uses and
applications
of the present construction will, however, become apparent to those skilled in
the art
after considering the specification and attached drawings. All such changes,
modifications, variations and other uses and applications which do not depart
from the
spirit and scope of the invention are deemed to be covered by the invention
which is
limited only by the claims that follow. The scope of the disclosure is not
intended to be
limited to the embodiments shown herein, but is to be accorded the full scope
consistent with the claims, wherein reference to an element in the singular is
not
intended to mean "one and only one" unless specifically so stated , but rather
one or
more. All structural and functional equivalents to the elements of the
embodiment
described throughout the disclosure that are known or later come to be known
to those
of ordinary skill in the art are expressly incorporated herein by reference
and intended
to be encompassed by the claims.
7
CA 3024639 2018-11-20
