U.S. patent application number 14/652876 was filed with the patent office on 2015-11-19 for a coupler.
This patent application is currently assigned to JB ATTACHMENTS LIMITED. The applicant listed for this patent is JB ATTACHMENTS LIMITED. Invention is credited to Surajith RAVINDRAN.
Application Number | 20150330053 14/652876 |
Document ID | / |
Family ID | 50978782 |
Filed Date | 2015-11-19 |
United States Patent
Application |
20150330053 |
Kind Code |
A1 |
RAVINDRAN; Surajith |
November 19, 2015 |
A COUPLER
Abstract
A coupler assembly for coupling implements of the type having
two connecting pins, to a vehicle. The coupler has a body component
that is connectable to the vehicle, and the body component includes
a forward recess for receiving a first connecting pin of an
implement. The coupler also has a movable component which is
supported by the body component and which is movable through a
range of travel relative to the body component. The movable
component includes, or forms a part of an aft recess for receiving
a second connecting pin of the implement. An actuator selectively
moves the movable component relative to the body component. A rear
locking member is a part of the movable component and a rear lock
actuator allows the rear locking member to be employed to prevent
the second connecting pin from exiting the aft recess.
Inventors: |
RAVINDRAN; Surajith;
(Auckland, NZ) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
JB ATTACHMENTS LIMITED |
Wiri, Auckland |
|
NZ |
|
|
Assignee: |
JB ATTACHMENTS LIMITED
Auckland
NZ
|
Family ID: |
50978782 |
Appl. No.: |
14/652876 |
Filed: |
December 11, 2013 |
PCT Filed: |
December 11, 2013 |
PCT NO: |
PCT/NZ2013/000228 |
371 Date: |
June 17, 2015 |
Current U.S.
Class: |
29/426.5 ;
403/91 |
Current CPC
Class: |
E02F 3/3645 20130101;
E02F 3/3659 20130101; E02F 3/3618 20130101; E02F 3/3622 20130101;
Y10T 29/49824 20150115; E02F 3/3663 20130101; Y10T 403/32319
20150115; E02F 3/365 20130101 |
International
Class: |
E02F 3/36 20060101
E02F003/36 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 18, 2012 |
NZ |
604858 |
Claims
1. A coupler assembly for coupling implements having a first
connecting pin and a second connecting pin, to a vehicle, the
coupler having; a body component that is connectable to the
vehicle, and which includes a forward recess for receiving the
first connecting pin, a movable component which is supported by the
body component and which is movable through a range of travel
relative to the body component, and which includes, or forms a part
of, an aft recess for receiving the second connecting pin, and, a
movable component actuator for selectively moving the movable
component relative to the body component, a rear locking member
which is a part of the movable component and which is movable
relative to the movable component between an extended position in
which the rear locking member prevents the second connecting pin
from exiting the aft recess and a retracted position in which the
rear locking member does not prevent the second connecting pin
exiting the aft recess, and a rear lock actuator for moving the
rear locking member between its extended and retracted
positions.
2. The coupler assembly as claimed in claim 1, wherein a connection
between the rear lock actuator and the rear locking member includes
a link member.
3. The coupler assembly as claimed in claim 2, wherein the rear
locking member and the link member are configured in such a manner
that; an initial range of movement of the link member pushes the
rear locking member from its retracted position to its extended
position, and a second and further range of movement of the link
member positions a stop member which prevents movement of the rear
locking member away from its extended position.
4. The coupler assembly as claimed in claim 2, wherein the stop
member is a part of the link member.
5. The coupler assembly as claimed in claim 1, wherein the rear
lock actuator is mounted on the movable component.
6. The coupler assembly as claimed in claim 1, wherein the movable
component slides relative to the body component.
7. The coupler assembly as claimed in claim 2, wherein the link
member slides relative to the movable component.
8. The coupler assembly as claimed in claim 1, wherein the rear
locking member is pivotally connected to the movable component.
9. The coupler assembly as claimed in claim 1, wherein the coupler
further includes a forward locking member which is movable relative
to the body component between an extended position in which the
forward locking member prevents the first connecting pin from
exiting the forward recess and a retracted position in which the
forward locking member does not prevent the first connecting pin
exiting the forward recess.
10. The coupler assembly as claimed in claim 9, wherein the coupler
includes a forward lock actuator for moving the forward locking
member between its extended and retracted positions.
11. The coupler assembly as claimed in claim 10, wherein the
forward lock actuator is pivotally connected to a hydraulic
manifold of the coupler assembly.
12. The coupler assembly as claimed in claim 11, wherein the
pivotal connection between the forward lock actuator and the
hydraulic manifold is configured to provide a hydraulic fluid flow
path between the hydraulic manifold and the forward lock
actuator.
13. The coupler assembly as claimed in claim 1, wherein a hydraulic
system of the coupler includes sequence valves to control the
sequence of operation of the movable component actuator, the rear
lock actuator and the forward lock actuator during any engagement
and/or disengagement processes.
14. A coupler assembly for coupling implements having a first
connecting pin and a second connecting pin, to a vehicle, the
coupler assembly having; a forward recess for receiving the first
connecting pin, an aft recess for receiving the second connecting
pin, a forward locking member for securing the first connecting pin
within the forward recess, a hydraulic system including at least
one actuator configured to enable the coupler assembly to
positively engage with the first and second connecting pins of an
implement, and the hydraulic system also including at least one
hydraulic manifold block; wherein the coupler assembly also
includes a hydraulic forward lock actuator which is supported on,
and receives a hydraulic supply from, the hydraulic manifold
block.
15. The coupler assembly as claimed in claim 14, wherein forward
lock actuator is pivotally connected to the hydraulic manifold
block.
16. The coupler assembly as claimed in claim 15, wherein the
hydraulic supply from the hydraulic manifold block to the forward
lock actuator passes through the pivotal connection between the
forward lock actuator and the hydraulic manifold block.
17. The coupler assembly as claimed in claim 14, wherein the
forward lock actuator is a single acting actuator with a spring
return mechanism.
18. A vehicle incorporating at least one coupler substantially as
claimed in claim 1.
19. A method of disengaging a work attachment or implement from a
coupler having a body and a movable component, including the steps
of; operating a forward lock actuator to move a forward locking
member from an extended position to a retracted position, operating
a rear lock actuator to move a rear locking member from an extended
position to a retracted position, and when the rear locking member
is in its retracted position, operating a movable component
actuator to move a movable component out of engagement with a rear
pin of the work attachment, and then disengaging a forward pin of
the work attachment from the body.
20. The coupler assembly as claimed in claim 19, wherein the method
of disengaging includes an automatic operation of the forward lock
actuator to move the forward locking member from the retracted
position to the extended position a pre-determined time period
after the operation of the forward lock actuator, the rear lock
actuator or the movable component actuator to disengage the coupler
from an implement.
Description
FIELD OF THE INVENTION
[0001] This invention relates to a coupler, and in particular, but
not exclusively to a coupler for attaching work implements to the
arm or boom of an excavator or similar vehicle.
BACKGROUND
[0002] Couplers are often used to connect work attachments or
implements to the booms of excavators, diggers, back hoes, etc. The
couplers are sometimes also referred to as "quick hitches", or "pin
grabber" couplers as they grab the two connecting pins that are
attached to many attachments for the purpose of connecting the
attachment to an arm.
[0003] The couplers allow implements to be changed quickly and
efficiently by being able to release the connecting pins of one
implement, and to grab the connecting pins of another, using
remotely controlled hydraulic actuators on the coupler.
[0004] The ability to quickly change implements however, has lead
to an increasing number of accidents involving implements coming
loose, or falling from diggers etc. Most couplers today will have a
safety locking feature that will hold one of the pins of an
implement if the coupler fails, or if the other pin comes free for
some reason.
[0005] Experience shows that a single safety lock feature is not
sufficient. Accidents are still occurring as a result of the use of
these quick change couplers having a single safety feature. While
it is possible to add additional safety locks, the locks need to be
robust to withstand the harsh environment and rough treatment that
couplers experience at the end of an excavator arm. For example,
dirt or other foreign matter can accumulate within coupler
components which may affect the operation of the coupler or its
safety features. For this reason any additional safety locks need
to be relatively simple and durable, to ensure high levels of
reliability of the locks.
[0006] There are also limitations concerning the number of
hydraulic lines that are used to control hydraulic couplers. Simply
adding additional lines for each additional safety lock is not
always convenient and can be costly to install and maintain. There
is a requirement to provide additional safety features without the
need for additional hydraulic lines.
[0007] In this specification unless the contrary is expressly
stated, where a document, act or item of knowledge is referred to
or discussed, this reference or discussion is not an admission that
the document, act or item of knowledge or any combination thereof
was at the priority date, publicly available, known to the public,
part of common general knowledge; or known to be relevant to an
attempt to solve any problem with which this specification is
concerned.
OBJECT
[0008] It is therefore an object of the present invention to
provide a coupler which will at least go some way towards
overcoming one or more of the above mentioned problems, or at least
provide the public with a useful choice.
STATEMENTS OF THE INVENTION
[0009] Accordingly, in a first aspect, the invention may broadly be
said to consist in a coupler assembly for coupling implements
having a first connecting pin and a second connecting pin, to a
vehicle, the coupler having; [0010] a body component that is
connectable to the vehicle, and which includes a forward recess for
receiving the first connecting pin, [0011] a movable component
which is supported by the body component and which is movable
through a range of travel relative to the body component, and which
includes, or forms a part of, an aft recess for receiving the
second connecting pin, and, [0012] a movable component actuator for
selectively moving the movable component relative to the body
component, [0013] a rear locking member which is a part of the
movable component and which is movable relative to the movable
component between an extended position in which the rear locking
member prevents the second connecting pin from exiting the aft
recess and a retracted position in which the rear locking member
does not prevent the second connecting pin exiting the aft recess,
[0014] and a rear lock actuator for moving the rear locking member
between its extended and retracted positions.
[0015] Preferably a connection between the rear lock actuator and
the rear locking member includes a link member.
[0016] Preferably the rear locking member and the link member are
configured in such a manner that; [0017] an initial range of
movement of the link member pushes the rear locking member from its
retracted position to its extended position, and [0018] a second
and further range of movement of the link member positions a stop
member which prevents movement of the rear locking member away from
its extended position.
[0019] Preferably the stop member is a part of the link member.
[0020] Preferably the rear lock actuator is mounted on the movable
component.
[0021] Preferably the movable component slides relative to the body
component.
[0022] Preferably the link member slides relative to the movable
component.
[0023] Preferably the rear locking member is pivotally connected to
the movable component.
[0024] Preferably the coupler further includes a forward locking
member which is movable relative to the body component between an
extended position in which the forward locking member prevents the
first connecting pin from exiting the forward recess and a
retracted position in which the forward locking member does not
prevent the first connecting pin exiting the forward recess.
[0025] Preferably the coupler includes a forward lock actuator for
moving the forward locking member between its extended and
retracted positions.
[0026] Preferably the forward lock actuator is pivotally connected
to a hydraulic manifold of the coupler assembly.
[0027] Preferably the pivotal connection between the forward lock
actuator and the hydraulic manifold is configured to provide a
hydraulic fluid flow path between the hydraulic manifold and the
forward lock actuator.
[0028] Preferably the movable component actuator, the rear lock
actuator and the forward lock actuator are all hydraulic
actuators.
[0029] Preferably a hydraulic system of the coupler includes
sequence valves to control the sequence of operation of the movable
component actuator, the rear lock actuator and the forward lock
actuator during any engagement and/or disengagement processes.
[0030] In a second aspect, the invention may broadly be said to
consist in a coupler assembly for coupling implements having a
first connecting pin and a second connecting pin, to a vehicle, the
coupler assembly having; [0031] a forward recess for receiving the
first connecting pin, [0032] an aft recess for receiving the second
connecting pin, [0033] a forward locking member for securing the
first co/meeting pin within the forward recess, [0034] a hydraulic
system including at least one actuator configured to enable the
coupler assembly to positively engage with the first and second
connecting pins of an implement, and [0035] the hydraulic system
also including at least one hydraulic manifold block;
[0036] wherein the coupler assembly also includes a hydraulic
forward lock actuator which is supported on, and receives a
hydraulic supply from, the hydraulic manifold block.
[0037] Preferably forward lock actuator is pivotally connected to
the hydraulic manifold block.
[0038] Preferably the hydraulic supply from the hydraulic manifold
block to the forward lock actuator passes through the pivotal
connection between the forward lock actuator and the hydraulic
manifold block.
[0039] Preferably the forward lock actuator is a single acting
actuator with a spring return mechanism.
[0040] In a third aspect, the invention may broadly be said to
consist in a vehicle incorporating at least one coupler
substantially as specified herein.
[0041] Preferably the vehicle is an excavator.
[0042] In a fourth aspect, the invention may broadly be said to
consist in a method of disengaging a work attachment or implement
from a coupler having a body and a movable component, including the
steps of; [0043] operating a forward lock actuator to move a
forward locking member from an extended position to a retracted
position, [0044] operating a rear lock actuator to move a rear
locking member from an extended position to a retracted position,
[0045] and when the rear locking member is in its retracted
position, operating a movable component actuator to move a movable
component out of engagement with a rear pin of the work attachment,
[0046] and then disengaging a forward pin of the work attachment
from the body.
[0047] Preferably the method of disengaging includes an automatic
operation of the forward lock actuator to move the forward locking
member from the retracted position to the extended position a
pre-determined time period after the operation of the forward lock
actuator, the rear lock actuator or the movable component actuator
to disengage the coupler from an implement.
[0048] The invention may also broadly be said to consist in the
parts, elements and features referred to or indicated in the
specification of the application, individually or collectively, and
any or all combinations of any two or more of the parts, elements
or features, and where specific integers are mentioned herein which
have known equivalents, such equivalents are incorporated herein as
if they were individually set forth.
DESCRIPTION
[0049] Further aspects of the present invention will become
apparent from the following description which is given by way of
example only and with reference to the accompanying drawings in
which:
[0050] FIG. 1 is an exploded perspective view of a first example of
a coupler according to the present invention,
[0051] FIG. 2 is a cutaway perspective view of the first example of
a coupler,
[0052] FIG. 3 is a cutaway perspective view of a slide assembly of
the first example of a coupler,
[0053] FIG. 4 is a perspective view of a slide component of the
slide assembly,
[0054] FIG. 5 is a perspective view of a forward locking member of
the first example of a coupler,
[0055] FIG. 6 is a perspective view of a rear locking member of the
slide assembly,
[0056] FIG. 7 is a perspective view of a link member of the slide
assembly,
[0057] FIG. 8 is a perspective view of a slide assembly actuator of
the first example of a coupler,
[0058] FIG. 9 is a right side elevation view of the first example
of a coupler,
[0059] FIG. 10 is a cutaway side elevation view of the first
example of a coupler,
[0060] FIG. 11 is a perspective view of a rear lock actuator of the
first example of a coupler,
[0061] FIG. 12 is a cutaway side elevation view of the coupler
showing a first stage of a coupling sequence,
[0062] FIG. 13 is a cutaway side elevation view of the coupler
showing a second stage of a coupling sequence,
[0063] FIG. 14 is a cutaway side elevation view of the coupler
showing a third stage of a coupling sequence,
[0064] FIG. 15 is a cutaway side elevation view of the coupler
showing a fourth stage of a coupling sequence,
[0065] FIG. 16 is a cutaway side elevation view of the coupler
showing a first stage of an uncoupling sequence,
[0066] FIG. 17 is a cutaway side elevation view of the coupler
showing a second stage of an uncoupling sequence,
[0067] FIG. 18 is a cutaway side elevation view of the coupler
showing a third stage of an uncoupling sequence,
[0068] FIG. 19 is a cutaway side elevation view of the coupler
showing a fourth stage of an uncoupling sequence,
[0069] FIG. 20 is a cutaway side elevation view of the coupler
showing a fifth stage of an uncoupling sequence,
[0070] FIG. 21 is a schematic diagram of a hydraulic circuit which
includes components of the coupler as well as hydraulic components
of a vehicle, to which the coupler is attached,
[0071] FIG. 22 is an electrical diagram used to control the
operation of the coupler,
[0072] FIG. 23 is a partially cutaway side elevation view of a
second example of a coupler according to the present invention,
showing a forward locking member of the coupler in an extended
configuration,
[0073] FIG. 24 is a partially cutaway side elevation view of the
second example of a coupler showing the forward locking member in a
retracted configuration,
[0074] FIG. 25 is a partially cutaway perspective view of the
second example of a coupler which defines an exploded view A,
and
[0075] FIG. 26 is the exploded view A which shows the hydraulic
supply routing to a forward lock actuator which controls the
positioning of the forward locking member.
FIRST EXAMPLE
[0076] With reference to FIGS. 1 to 22, a first example of a
coupler assembly (31) is shown in an exploded perspective view and
in a series of perspective and cutaway views. Included also are
hydraulic and electrical circuits used to control the operation of
the coupler assembly (31). The coupler assembly (31) is of the type
typically used for coupling implements having a first connecting
pin and a second connecting pin, to a vehicle such as an excavator
or a back hoe.
[0077] It can be seen in FIGS. 1 and 2 that the coupler assembly
(31) has a body component (33) that is connectable to the vehicle.
The body component (33) itself includes two coupler mounting pins
(35) which are used to connect the coupler assembly (31) to the end
of an arm of the vehicle. The body component (33) also includes a
forward recess (37) for receiving the first connecting pin of an
implement.
[0078] The coupler assembly (31) also includes a movable component
or slide assembly (39) which is supported by the body component
(33). The slide assembly (39) is movable through a range of travel
relative to the body component (33). The range of travel of the
slide assembly (39) is substantially in a fore and aft direction
relative to the body (33). The slide assembly (39) includes, or at
least forms a part of, an aft recess (41) for receiving the second
connecting pin of an implement.
[0079] A movable component actuator or slide assembly actuator (43)
of the coupler assembly (31) is used to selectively move the slide
assembly (39) relative to the body component (33). With reference
to FIG. 4 it can be seen that a slide component (45) of the slide
assembly (39) includes elongate tabs (47). These elongate tabs (47)
engage with corresponding slots (49) on the body component (33),
allowing the slide assembly (39) to slide in a fore and aft
direction relative to the body component (33).
[0080] The slide assembly (39) includes a rear locking member (51).
The rear locking member (51) is movable relative to the slide
assembly (39), between an extended position in which the rear
locking member (51) prevents the second connecting pin from exiting
the aft recess (41) and a retracted position in which the rear
locking member (51) does not prevent the second connecting pin
exiting the aft recess (41).
[0081] The slide assembly (39) also includes a rear lock actuator
(53) (refer FIGS. 2, 3 and 11) for moving the rear locking member
(51) between its extended and retracted positions. The rear lock
actuator (53) is mounted on the slide assembly (39), and moves with
the slide assembly (39). The rear lock actuator (53) includes a
rear lock actuator spring (54) which biases the actuator toward an
extended configuration in which the rear lock actuator (53) pushes
the rear locking member (51) to its extended position.
[0082] A feature of the coupler assembly (31) is the connection
between the rear lock actuator (53) and the rear locking member
(51). The connection includes a link member (55). The rear locking
member (51) is pivotally connected to the slide component (45) by a
rear lock connecting pin (57). The link member (55) slides fore and
aft relative to the slide assembly (39) under the influence of the
rear lock actuator (53).
[0083] The rear locking member (51) and the link member (55) are
configured in such a manner that an initial range of movement of
the link member (55) pushes the rear locking member (51) from its
retracted position to its extended position. And a second and
further range of movement of the link member (55) positions a stop
member (59) which prevents movement of the rear locking member (51)
away from its extended position. In this example, the stop member
(59) is a part of the link member (55).
[0084] It can be seen in FIG. 7 that the link member (55) is in the
form of a substantially rectangular shaped plate (61), having tabs
(63) extending from the plate (61) for connection to the rear lock
actuator (53). The plate (61) includes a rectangular shaped hole
(65) positioned substantially centrally within the principal plane
of the plate (61). Alternatively, it could be said that the link
member (55) comprises a forward transverse member (67), and aft
transverse member (69), and side plates (71), one on the left side
and one on the right side of the link member (55). The side plates
(71) each span between the outermost extremities of the forward and
aft transverse members (67) and (69).
[0085] The side plates (71) of the link member (55) engage with,
and slide within, slide grooves (73) on each side of the slide
assembly (39).
[0086] Similarly, it can be seen in FIG. 6 that the rear locking
member (51) includes an upwardly protruding control tab (75), and
two rearwardly extending locking tabs (77). The two rearwardly
extending locking tabs (77) each include a locking surface (79).
The locking surfaces (79) are situated on an upper part of each
locking tab (77) and are substantially aligned with a lower edge
(81) of the slide grooves (73) when the rear locking member (51) is
in its fully extended position.
[0087] When the slide assembly (39) is assembled, the link member
(55) is held within the slide grooves (73). And when the rear
locking member (51) is in its fully extended position, the control
tab (75) of the rear locking member (51) is situated within the
rectangular hole (65) in the link member (55). The rectangular hole
(65) is of sufficient size to allow a range of movement of the link
member (55) relative to the rear locking member (51) without
contact being made between the link member (55) and the rear
locking member (51). However, movement of the link member beyond
this range of movement does result in contact between the link
member (55) and the rear locking member (51). And this contact is
used to move the rear locking member (51) between its retracted
position and its extended position as will be explained below.
[0088] Movement of the rear locking member (51) from its retracted
position to its extended position is achieved as follows. The link
member (55) is moved from its forward most position, and in an aft
direction, by the rear lock actuator (53). During an initial range
of movement of the link member (55) in an aft direction, an aft
edge (83) of the side plates (71) contacts a forward edge (85) of
the locking tabs (77). This contact causes rotation of the rear
locking member (51) about the rear lock connecting pin (57), and
rotation of the rear locking member (51) to its fully extended
position.
[0089] Continued movement of the link member (55) in an aft
direction does not cause any further movement of the rear locking
member (51), however the continued movement positions the side
plates (71) of the link member (55) over the locking surfaces (79)
of the rear locking member (51). The rectangular hole (65) in the
link member (55) is configured to allow continued aft movement of
the link member (55) even though the control tab (75) is now
situated within the rectangular hole (65). Also, the slide assembly
(39) is configured such that the locking surfaces (79) are
immediately adjacent the side plates (71) when the link member (55)
is fully aft. In this way, the side plates (71) act as stops
preventing movement of the rear locking member (51) away from its
fully extended position.
[0090] Any forces experienced by the rear locking member (51), for
example if the second connecting pin of a work implement was trying
to exit the aft recess (41), would result in the locking surfaces
(79) bearing upwards against the under side of the side plates
(71). This upward force from the locking surfaces (79) would be
restrained by the engagement of the link member (55) within the
slide grooves (73). This is advantageous in that these forces
experienced by the rear locking member (51) are not felt directly
by the rear lock actuator (53).
[0091] Movement of the rear locking member (51) from its extended
position to its retracted position is achieved as follows. The link
member (55) is moved forward by the rear lock actuator (53). An
initial range of forward movement of the link member (55) moves the
side plates (71) away from their location above the locking
surfaces (79). This unlocks the rear locking member (51) allowing
it to be moved to its retracted position. A second range of forward
movement of the link member (55) initially brings a forward edge
(87) of the rear transverse member (69) into contact with a rear
surface (89) of the control tab (75).
[0092] Continued forward movement of the link member (55) pushes
the control tab (75) forward causing the rear locking member (51)
to move to its retracted position. The rear locking member (51) is
held in its retracted position by the rear transverse member (69)
which lies above the control tab (75) and adjacent to it, when the
rear locking member (51) is in its retracted position.
[0093] The coupler assembly (31) further includes a forward locking
member (91). The forward locking member (91) is movable relative to
the body component (33) between an extended position, in which the
forward locking member (91) prevents the first connecting pin from
exiting the forward recess (37), and a retracted position, in which
the forward locking member does not prevent the first connecting
pin exiting the forward recess (37).
[0094] The coupler assembly (31) also includes a forward lock
actuator (93) for moving the forward locking member (91) between
its extended and retracted positions.
[0095] In this example, the coupler assembly (31) is used with a
hydraulic control system (111) and an electrical control circuit
(113) as shown in FIGS. 21 and 22 respectively.
[0096] The electrical control circuit (113) includes two manually
controlled switches and a timer, and the hydraulic control system
(111) includes solenoid operated control valves and sequence
valves, to control the sequence of operation of the slide assembly
actuator (43), the rear lock actuator (53) and the forward lock
actuator (93), during any engagement and/or disengagement
processes. The design of the hydraulic control system (111) allows
the coupler assembly (31) to be controlled using only two hydraulic
lines. The electrical and hydraulic control systems will now be
explained in further detail.
[0097] The electrical control circuit (113) has a master switch
(115) which is used to supply or disconnect electrical power to the
control circuit. When the master switch (115) is switched on an
alarm (117) sounds and optionally a warning light operates also.
This warns personal in the vicinity of the vehicle that the coupler
(31) will be operated to release and/or engage implements from the
aim of the vehicle.
[0098] A second switch (119) is a `hold to run` style of switch,
meaning that the contacts of the switch are only engaged while the
operator continues to hold the switch down. When the second switch
(119) is pushed "on" a second alarm (121) and warning light
operates, and power is supplied to a first solenoid operated valve
(123) of the hydraulic control system (111). A timer (125) is also
initiated, which in turn provides power to a second solenoid
operated valve (127) via a timer relay (128), after a
pre-determined time period, for example a time period in the range
of three to eight seconds.
[0099] The first and second solenoid operated valves (123) and
(127) of the hydraulic control system (111) are situated on the
vehicle along with a pressure regulating valve (129) for regulating
the hydraulic pressure to a set value and minimising pressure
spikes. The first solenoid operated valve (123) is used to initiate
the disengage or engage signals to the coupler (31). The second
solenoid operated valve (127) controls the draining of hydraulic
fluid from the forward lock actuator (93) after the pre-determined
time delay period to allow a forward lock actuator spring (99)
within the forward lock actuator (93) to move the forward locking
member (91) backs to its extended position.
[0100] Two hydraulic lines, a supply line (131) and a return line
(133), are used to power and control the coupler assembly (31).
[0101] The coupler assembly (31) itself includes a first sequence
valve (135) which controls the sequencing of the three actuators
and ensures that the rear lock actuator (53) and the forward lock
actuator (93) operate to retract their respective locking members
(51) and (91) prior to the retraction of the slide assembly
actuator (43) to move the slide assembly (39) forward.
[0102] A first pressure operated check valve (137) and a second
pressure operated check valve (139) act as safety locks to lock the
position of the slide assembly actuator (43) in case of a hydraulic
failure. The locked slide assembly actuator (43) holds the slide
assembly (39) fixed preventing the pins of an implement from
exiting the forward and aft recess (37) and (41) of the coupler
(31).
[0103] A second sequence valve (141) controls the sequencing of the
slide assembly actuator (43) and the rear lock actuator (53) to
ensure that the rear lock actuator (43) moves the rear locking
member (51) to its retracted position before the slide assembly
actuator (43) begins to move the slide assembly (39) aft.
[0104] A third pressure operated check valve (143) isolates the
rear lock actuator (53) from the forward lock actuator (93) when
fluid is drained from the forward lock actuator (93) by the second
solenoid operated valve (127) as described above.
[0105] With reference to FIGS. 15 to 20 the dis-engagement sequence
will now be described.
[0106] At the beginning of this sequence (refer FIG. 15) the slide
assembly actuator (43) is at least partly extended and is holding
the slide assembly (39) in engagement with an aft connecting pin
(95) of an implement. The rear lock actuator (53) is extended under
hydraulic pressure and the rear locking member (51) is in its
extended position and is able to prevent the aft connecting pin
(95) from exiting the aft recess (41). The forward lock actuator is
retracted under spring tension only and is holding the forward
locking member (91) in its extended position and is able to prevent
a forward connecting pin (97) from exiting the forward recess
(37).
[0107] To initiate the disengagement procedure, the master switch
(115) is switched on. Then the second switch (119), the `hold to
run switch` is depressed. The first solenoid operated valve (123)
then operates to provide hydraulic pressure to the return line
(133). Due to the configuration of the first sequence valve (135)
the hydraulic pressure is initially directed to the rear lock
actuator (53) and the forward lock actuator (93) to retract the
rear and forward locking members (51) and (91)--refer to FIG.
16.
[0108] When the rear lock actuator (53) and the forward lock
actuator (93) have operated, pressure in the return line (133)
builds until the first sequence valve (135) opens to allow pressure
to the retract side of the slide assembly actuator (43) and to the
pilot line of the first pressure operated check valve (137),
allowing the slide assembly actuator (43) to retract and to move
the slide assembly (39) fully forward--refer to FIG. 17. This
disengages the aft connecting pin (95) from the aft recess
(41).
[0109] Then the coupler assembly (31) is rotated, for example by
using the crowd actuator of the excavator, to allow the coupler
assembly (31) to be moved aft without re-engaging with the aft
connecting pin (95) in the aft recess (41)--refer FIG. 18.
[0110] Then the coupler assembly (31) is moved aft to disengages
the forward connecting pin (97) from the forward recess (37) to
complete the disengaging procedure--refer FIG. 19.
[0111] FIG. 20 shows the subsequent movement of the forward locking
member (91) to its extended position after the time delay period.
After the set time period, the second solenoid operated valve (127)
operates to vent the fluid from the forward lock actuator (93),
allowing a spring (9) within the forward lock actuator (93) to
retract the actuator and move the forward locking member (91) to
its extended position. The pressure operated check valves (137),
(139) and (143) prevent any movement of fluid from the slide
assembly actuator (43) and the rear lock actuator (53). This
automatic resetting of the forward locking member (91) to its
extended position is a safety feature ensuring that the forward
locking member (91) is ready to hold and secure the forward
connecting pin (97) of the next implement in the forward recess
(37) as soon as the pick up or engagement procedure begins.
[0112] With reference to FIGS. 12 to 15 the engagement sequence
will now be described.
[0113] The rear locking member (51) is retracted, and as noted
above, the forward locking member (91) is extended and ready to
hold and secure the forward connecting pin (97).
[0114] The coupler assembly (31) is manipulated, for example using
the arm of the excavator, to engage the forward connecting pin (97)
of the next implement within the forward recess (37). The forward
locking member (91) is configured so that it is pushed away from
its extended position by the forward connecting pin (97) as it
enters the forward recess (37)--refer to FIG. 12. The coupler
assembly (31) is configured such that the spring (99) pushes the
forward locking member (91) back to its extended position once the
forward connecting pin (97) has passed fully into the forward
recess (37)--refer to FIG. 13.
[0115] The operator of the excavator then rotates the coupler
assembly (31) until the body (33) touches the aft connecting pin
(95) of the implement. And then the `hold to run` or second switch
(119) is released by the operator. This causes the first solenoid
operated valve (123) to become de-energised and it returns to its
steady state configuration as shown in FIG. 21. This connects the
hydraulic supply pressure to the supply line (131). This supplies
hydraulic pressure to the extend side of the slide assembly
actuator (43) and opens the second pressure operated check valve
(139) allowing the slide assembly actuator (43) to extend and to
move the slide assembly (39) aft toward the aft connecting pin
(95)--refer to FIG. 14.
[0116] When the slide assembly (39) engages with the aft connecting
pin (95) the pressure builds on the extend side of the slide
assembly actuator (43) until there is sufficient pressure to
operate the second sequence valve (141). Then pressure is supplied
to the extend side of the rear lock actuator (53), the rear lock
actuator (53) then extends and moves the rear locking member to its
extended position--refer to FIG. 15.
[0117] This is the configuration that the coupler assembly (31)
remains in while the excavator or other vehicle is using the
coupler assembly (31) to hold an implement. A first locking feature
is provided by the first and second pressure operated check valves
(137) and (139) which hydraulically lock the slide assembly
actuator (43) in the case of a hydraulic failure, for example a
rupture of the supply or return lines (131) or (133). A second
locking feature is provided by the forward locking member (91)
which holds the forward connecting pin (97) within the forward
recess (37). And a third locking feature is provided by the rear
locking member (51) which holds the aft connecting pin (95) within
the aft recess (41).
[0118] It can be said that in use, the coupler assembly (31)
employs the following method of disengaging a work attachment or
implement from the coupler assembly (31); [0119] the forward lock
actuator (93) is operated to move the forward locking member (91)
from its extended position to its retracted position, [0120] the
rear lock actuator (53) is operated to move the rear locking member
(51) from its extended position to its retracted position, [0121]
and when the rear locking member (51) is in its retracted position,
the slide assembly actuator (43) is operated to move the slide
assembly (39) out of engagement with a rear pin (95) of the work
attachment, [0122] and when the forward locking member (91) is
retracted and the rear pin (95) is no longer engaged within the
slide assembly (39), the forward pin (97) of the work attachment is
disengaged from the body (33).
[0123] With the coupler assembly (31), the method of disengaging
also includes an automatic operation of the forward lock actuator
(93) to move the forward locking member (91) from the retracted
position to the extended position a pre-determined time period
after the operation of; [0124] the forward lock actuator (93),
[0125] the rear lock actuator (53), or [0126] the slide assembly
actuator (43),
[0127] to disengage the coupler (31) from an implement.
SECOND EXAMPLE
[0128] With reference to FIGS. 23 to 26, a second example of a
coupler assembly (161) will now be described. The operation of the
coupler assembly (161) is similar to that of the first example of a
coupler assembly (31), and the only significant difference between
the first and second examples is the configuration of a forward
locking assembly (163).
[0129] In this second example, a forward lock actuator (165) of the
forward locking assembly (163) is pivotally connected at its aft
end to a hydraulic manifold block (167) of the coupler assembly
(164 In this way the forward lock actuator (165) is supported by
the hydraulic manifold block (167). The hydraulic manifold block
(167) routes fluid for a slide actuator (169) and a rear lock
actuator (171), and also routes hydraulic fluid directly to the
forward lock actuator (165).
[0130] A pivot pin (173) connects an aft end of the forward lock
actuator (165) to the hydraulic manifold block (167). A first
passage (175) within the hydraulic manifold block (167)
communicates with a second passage (177) within the pivot pin
(173). The second passage (177) communicates with the hydraulic
cylinder (179) of the forward lock actuator (165) via a third
passageway (181) in an end fitting (183) of the forward lock
actuator (165).
[0131] In this way, hydraulic fluid can be directed to or from the
forward lock actuator (165) to extend or retract a forward locking
member (185). As can be seen in FIG. 26, the forward lock actuator
(165) is a single acting actuator with a spring return mechanism.
For this reason the forward lock actuator (165) only requires a
single hydraulic supply.
[0132] This configuration eliminates the need for an external
hydraulic connection to the forward lock actuator (165), while at
the same time allowing the forward lock actuator (165) to pivot as
it moves the forward locking member (185). This allows a compact
configuration of the forward locking assembly (163), and the
configuration is expected to have a high reliability.
Variations
[0133] To those skilled in the art to which the invention relates,
many changes in construction and widely differing embodiments and
applications of the invention will suggest themselves without
departing from the scope of the invention as defined in the
appended claims. The disclosures and the description herein are
purely illustrative and are not intended to be in any sense
limiting.
[0134] In the examples described above, the slide assembly
actuator, the rear lock actuator and the forward lock actuator are
all hydraulic actuators. However it is envisaged that alternative
actuators could be used, for example electrically operated linear
actuators.
Definitions
[0135] Throughout this specification the word "comprise" and
variations of that word, such as "comprises" and "comprising", are
not intended to exclude other additives, components, integers or
steps.
Advantages
[0136] Thus it can be seen that at least the preferred form of the
invention provides a coupler which provides a high level of safety.
The rear locking member locks the aft connecting pin positively
within the aft recess and the arrangement of the rear lock actuator
and its connection to the rear locking member provides a positive
and robust lock of the rear locking member in its extended
position. The configuration of the locks is relatively simple and
not excessively prone to interference from dirt or other foreign
matter that may accumulate around the components.
[0137] The coupler assembly can be controlled using only two
hydraulic lines which is advantageous as it eliminates the need for
additional lines where two are already available.
[0138] Also, the hydraulic actuators for the slide assembly, for
the forward lock and the rear lock are all isolated from one
another, meaning that in the event of a failure of one of the
actuators, the other two will continue to provide their safety
locking features. In addition, each actuator includes a biasing
means in the form of a spring which biases each actuator toward a
fail-safe configuration, that is, a configuration which retains the
pins of the implements within the coupler.
* * * * *