CA2727324A1 - Latching mechanism for a quick coupler - Google Patents
Latching mechanism for a quick coupler Download PDFInfo
- Publication number
- CA2727324A1 CA2727324A1 CA 2727324 CA2727324A CA2727324A1 CA 2727324 A1 CA2727324 A1 CA 2727324A1 CA 2727324 CA2727324 CA 2727324 CA 2727324 A CA2727324 A CA 2727324A CA 2727324 A1 CA2727324 A1 CA 2727324A1
- Authority
- CA
- Canada
- Prior art keywords
- quick coupler
- actuators
- latching
- latch bar
- pair
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/28—Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
- E02F3/36—Component parts
- E02F3/3604—Devices to connect tools to arms, booms or the like
- E02F3/3609—Devices to connect tools to arms, booms or the like of the quick acting type, e.g. controlled from the operator seat
- E02F3/3631—Devices to connect tools to arms, booms or the like of the quick acting type, e.g. controlled from the operator seat with a hook and a transversal locking element
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/28—Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
- E02F3/36—Component parts
- E02F3/3604—Devices to connect tools to arms, booms or the like
- E02F3/3609—Devices to connect tools to arms, booms or the like of the quick acting type, e.g. controlled from the operator seat
- E02F3/3663—Devices to connect tools to arms, booms or the like of the quick acting type, e.g. controlled from the operator seat hydraulically-operated
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
- E02F9/20—Drives; Control devices
- E02F9/22—Hydraulic or pneumatic drives
- E02F9/226—Safety arrangements, e.g. hydraulic driven fans, preventing cavitation, leakage, overheating
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/08—Characterised by the construction of the motor unit
- F15B15/14—Characterised by the construction of the motor unit of the straight-cylinder type
- F15B15/1404—Characterised by the construction of the motor unit of the straight-cylinder type in clusters, e.g. multiple cylinders in one block
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/20—Other details, e.g. assembly with regulating devices
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Mining & Mineral Resources (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Shovels (AREA)
Abstract
A quick coupler comprises a latching mechanism including a latch bar powered by a pair of actuators mounted in parallel at opposed end portions of the of the latch bar to jointly displace the bar between unlatching and latching positions. A fail-safe mechanism is integrated to at least one of the actuators to block the actuator in the latching position in the event of a malfunction of the system.
Description
LATCHING MECHANISM FOR A QUICK COUPLER
TECHNICAL FIELD
The application relates generally to quick couplers for detachably coupling a work implement/tool, such as a bucket, to the power operated arm or boom of an earth working machine, such as an excavator and, more particularly, to a latching mechanism for such quick couplers.
BACKGROUND OF THE ART
It is well known to use quick couplers for detachably coupling buckets, grapples and other work implements to earth working machines or heavy machinery, such as excavators, wheel loaders, power shovels and crawlers. Such quick couplers advantageously allow machine operators to rapidly change from one tool to another.
Quick couplers typically comprises a latch bar which is spring-loaded towards a latching position by a pair of coil springs disposed about guide rods extending from the body of the quick coupler. A single-acting hydraulic cylinder is typically centrally disposed between the coil springs and the guide rods to displace the latch bar against the biasing force of the coil springs to an unlatching position.
Accordingly, the springs are cycled each time the central hydraulic cylinder is powered. The frequent cycling of the springs tends to prematurely compromise the integrity of the springs, requiring premature replacement to avoid accidental unlatching of the tool from the body of the quick coupler. Also, in order to displace the latch bar to its unlatching position, the central hydraulic cylinder has to overcome the biasing force of the coil springs, thereby requiring greater power than it would normally be necessary to displace the latch bar alone.
It has also been found that under certain operating conditions, the loads transferred to the guide rods may plastically deform or even break the rods, requiring immediate replacement of the guide rods.
Furthermore, the use of separate systems for providing a latching force (the coil springs) and an unlatching force (the hydraulic cylinder) results in additional parts and costs. Accordingly, it is desirable to eliminate the need for a separate mechanical system for biasing the latch bar to its latching position. However, it has been heretofore challenging to do so since the latching system must prevent accidental unlatching of the tool in the event of a malfunction of the system used to actuate the latch bar.
Also it has been found that under certain operating conditions, the latch bar tends to jam in the brackets provided on the bucket. In some instances, the unlatching force provided by the centrally disposed hydraulic cylinder may be insufficient to overcome both the latching force of the coil springs and the friction forces between the latch bar and the bucket brackets, thereby preventing the quick coupler from being disengaged from the bucket.
SUMMARY
It is therefore an aim to provide a new latching mechanism for a quick coupler.
In one aspect, there is provided a quick coupler for detachably coupling a work implement to a power operated arm of an earth working machine, the work implement having a pair of brackets for engagement with the quick coupler, the brackets having a pair of wedge-shaped latching notches; the quick coupler comprising a body adapted to be mounted to a distal end of the power operated arm, the body of the quick coupler being configured for engagement between the brackets on the work implement, a transversal latch bar mounted to the body of the quick coupler, the transversal latch bar having opposed wedge-shaped end portions configured for mating engagement with respective ones of said wedge-shape latching notches of the brackets on the work implement, and a pair of actuators mounted to said body and connectable to a power system for jointly reciprocating said transversal latch bar back and forth between a latching position, wherein the opposed wedge-shaped end portions of the transversal latch bar are engaged in respective ones of the wedge-shaped latching notches of the brackets, and an unlatching position, wherein the opposed wedge-shaped end portions of the transversal latch bar are disengaged from the latching notches, the actuators being mounted side-by-side and connected to the transversal latch bar at locations adjacent to the opposed wedge-shaped end portions thereof, the actuators acting in conjunction to selectively provide both a latching force and an unlatching force, at least one of the actuators being coupled to a safety blocking device which is responsive to a malfunction or shut down of the power system to automatically block said at least one of the actuators in a position in which the at least one of the actuators maintains its latching force on the transverse latch bar.
In a second aspect, there is provided a quick coupler for detachably coupling a work implement to a power operated arm of an earth working machine, the work implement having a bracket arrangement for engagement with the quick coupler, the bracket arrangement having a latching notch; the quick coupler comprising a body adapted to be mounted to a distal end of the power operated arm, the body of the quick coupler being configured for engagement with the bracket arrangement on the work implement, a dead latch bar mounted to the body of the quick coupler, the dead latch bar configured for mating engagement with the latching notch of the bracket arrangement on the work implement, a pair of double-acting actuators mounted to said body and connectable to a power system for jointly displacing said dead latch bar between a latching position, wherein the dead latch bar is engaged in the latching notch of the bracket arrangement, and an unlatching position, wherein the dead latch bar is disengaged from the latching notch, the double-acting actuators selectively providing both latching and unlatching forces, and a fail-safe mechanism for blocking movement of at least one of said double-acting actuators in the event of a malfunction of the power system while the double-acting actuators are holding the dead latch bar in its latching position.
In a third aspect, there is provided a latching mechanism for securing a quick coupler to a work tool, the quick coupler being mounted to a distal end of an arm of an earth working machine; the latching mechanism comprising a cartridge removably insertable into a body of the quick coupler, the cartridge comprising a pair of side-by-side actuators extending from a common mounting plate adapted to be detachably secured to the body of the quick coupler, thereby providing for the simultaneous mounting of the side-by-side actuators to the body of the quick coupler by the attachment of the common mounting plate to the quick coupler.
Further details of these and other aspects of the present invention will be apparent from the detailed description and figures included below.
DESCRIPTION OF THE DRAWINGS
Reference is now made to the accompanying figures, in which:
Fig. 1 is a perspective fragmentary view of a bucket coupled to a quick coupler provided at a distal end of a power actuated arm of an earth working machine;
Fig. 2 is a perspective view of the quick coupler, the quick coupler having a latching mechanism including a transversal latch bar operated by a pair of side-by-side actuators;
Fig. 3 is a partly exploded view illustrating how the latching mechanism is front loaded and mounted as a unitary cartridge into the body of the quick coupler;
and Fig. 4 is a cross-section of the actuator mechanism of the latch bar.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Fig. 1 illustrates a quick coupler 10 for detachably coupling a material handling tool, such as a bucket 12, to the distal end of a power operated boom or arm 14 of an earth working machine, such as an excavator or the like (not shown).
The bucket 12 is provided on the back side thereof with a pair of upstanding rails or coupler receiving brackets 16. The brackets 16 are equally spaced-apart from the central axis of the bucket 12 and are configured for receiving the quick coupler 10 therebetween. Each bracket 16 may be provided at a first end thereof with a hook 18 defining a hook opening 20. Each bracket 16 may be provided at a second opposed end thereof with a wedge-shaped latching notch 22. A cradle opening 24 may also be defined in the top surface of each bracket 16 between the first and second opposed ends thereof.
TECHNICAL FIELD
The application relates generally to quick couplers for detachably coupling a work implement/tool, such as a bucket, to the power operated arm or boom of an earth working machine, such as an excavator and, more particularly, to a latching mechanism for such quick couplers.
BACKGROUND OF THE ART
It is well known to use quick couplers for detachably coupling buckets, grapples and other work implements to earth working machines or heavy machinery, such as excavators, wheel loaders, power shovels and crawlers. Such quick couplers advantageously allow machine operators to rapidly change from one tool to another.
Quick couplers typically comprises a latch bar which is spring-loaded towards a latching position by a pair of coil springs disposed about guide rods extending from the body of the quick coupler. A single-acting hydraulic cylinder is typically centrally disposed between the coil springs and the guide rods to displace the latch bar against the biasing force of the coil springs to an unlatching position.
Accordingly, the springs are cycled each time the central hydraulic cylinder is powered. The frequent cycling of the springs tends to prematurely compromise the integrity of the springs, requiring premature replacement to avoid accidental unlatching of the tool from the body of the quick coupler. Also, in order to displace the latch bar to its unlatching position, the central hydraulic cylinder has to overcome the biasing force of the coil springs, thereby requiring greater power than it would normally be necessary to displace the latch bar alone.
It has also been found that under certain operating conditions, the loads transferred to the guide rods may plastically deform or even break the rods, requiring immediate replacement of the guide rods.
Furthermore, the use of separate systems for providing a latching force (the coil springs) and an unlatching force (the hydraulic cylinder) results in additional parts and costs. Accordingly, it is desirable to eliminate the need for a separate mechanical system for biasing the latch bar to its latching position. However, it has been heretofore challenging to do so since the latching system must prevent accidental unlatching of the tool in the event of a malfunction of the system used to actuate the latch bar.
Also it has been found that under certain operating conditions, the latch bar tends to jam in the brackets provided on the bucket. In some instances, the unlatching force provided by the centrally disposed hydraulic cylinder may be insufficient to overcome both the latching force of the coil springs and the friction forces between the latch bar and the bucket brackets, thereby preventing the quick coupler from being disengaged from the bucket.
SUMMARY
It is therefore an aim to provide a new latching mechanism for a quick coupler.
In one aspect, there is provided a quick coupler for detachably coupling a work implement to a power operated arm of an earth working machine, the work implement having a pair of brackets for engagement with the quick coupler, the brackets having a pair of wedge-shaped latching notches; the quick coupler comprising a body adapted to be mounted to a distal end of the power operated arm, the body of the quick coupler being configured for engagement between the brackets on the work implement, a transversal latch bar mounted to the body of the quick coupler, the transversal latch bar having opposed wedge-shaped end portions configured for mating engagement with respective ones of said wedge-shape latching notches of the brackets on the work implement, and a pair of actuators mounted to said body and connectable to a power system for jointly reciprocating said transversal latch bar back and forth between a latching position, wherein the opposed wedge-shaped end portions of the transversal latch bar are engaged in respective ones of the wedge-shaped latching notches of the brackets, and an unlatching position, wherein the opposed wedge-shaped end portions of the transversal latch bar are disengaged from the latching notches, the actuators being mounted side-by-side and connected to the transversal latch bar at locations adjacent to the opposed wedge-shaped end portions thereof, the actuators acting in conjunction to selectively provide both a latching force and an unlatching force, at least one of the actuators being coupled to a safety blocking device which is responsive to a malfunction or shut down of the power system to automatically block said at least one of the actuators in a position in which the at least one of the actuators maintains its latching force on the transverse latch bar.
In a second aspect, there is provided a quick coupler for detachably coupling a work implement to a power operated arm of an earth working machine, the work implement having a bracket arrangement for engagement with the quick coupler, the bracket arrangement having a latching notch; the quick coupler comprising a body adapted to be mounted to a distal end of the power operated arm, the body of the quick coupler being configured for engagement with the bracket arrangement on the work implement, a dead latch bar mounted to the body of the quick coupler, the dead latch bar configured for mating engagement with the latching notch of the bracket arrangement on the work implement, a pair of double-acting actuators mounted to said body and connectable to a power system for jointly displacing said dead latch bar between a latching position, wherein the dead latch bar is engaged in the latching notch of the bracket arrangement, and an unlatching position, wherein the dead latch bar is disengaged from the latching notch, the double-acting actuators selectively providing both latching and unlatching forces, and a fail-safe mechanism for blocking movement of at least one of said double-acting actuators in the event of a malfunction of the power system while the double-acting actuators are holding the dead latch bar in its latching position.
In a third aspect, there is provided a latching mechanism for securing a quick coupler to a work tool, the quick coupler being mounted to a distal end of an arm of an earth working machine; the latching mechanism comprising a cartridge removably insertable into a body of the quick coupler, the cartridge comprising a pair of side-by-side actuators extending from a common mounting plate adapted to be detachably secured to the body of the quick coupler, thereby providing for the simultaneous mounting of the side-by-side actuators to the body of the quick coupler by the attachment of the common mounting plate to the quick coupler.
Further details of these and other aspects of the present invention will be apparent from the detailed description and figures included below.
DESCRIPTION OF THE DRAWINGS
Reference is now made to the accompanying figures, in which:
Fig. 1 is a perspective fragmentary view of a bucket coupled to a quick coupler provided at a distal end of a power actuated arm of an earth working machine;
Fig. 2 is a perspective view of the quick coupler, the quick coupler having a latching mechanism including a transversal latch bar operated by a pair of side-by-side actuators;
Fig. 3 is a partly exploded view illustrating how the latching mechanism is front loaded and mounted as a unitary cartridge into the body of the quick coupler;
and Fig. 4 is a cross-section of the actuator mechanism of the latch bar.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Fig. 1 illustrates a quick coupler 10 for detachably coupling a material handling tool, such as a bucket 12, to the distal end of a power operated boom or arm 14 of an earth working machine, such as an excavator or the like (not shown).
The bucket 12 is provided on the back side thereof with a pair of upstanding rails or coupler receiving brackets 16. The brackets 16 are equally spaced-apart from the central axis of the bucket 12 and are configured for receiving the quick coupler 10 therebetween. Each bracket 16 may be provided at a first end thereof with a hook 18 defining a hook opening 20. Each bracket 16 may be provided at a second opposed end thereof with a wedge-shaped latching notch 22. A cradle opening 24 may also be defined in the top surface of each bracket 16 between the first and second opposed ends thereof.
As best shown in Fig. 2, the quick coupler 10 has a body 26 including a pair spaced-apart side plates 28 interconnected by a bottom plate (not shown), a top plate 30 and a front plate 32. The body 26 of the coupler 10 is configured to fit between the coupler receiving brackets 16 on the bucket 12. A first axle 34 extends transversally through corresponding holes defined in a first end portion of the side plates 28. A second axle 36 extends transversally through corresponding holes defined of the side plates 28. The second end portion of each side plate 28 has a distal nose portion defining an elongated guide slot 38.
As shown in Fig. 1, the quick coupler 10 is pivotally connected to the arm 14 of the earth working machine by the first axle 34. The second axle 36 of the coupler 10 is pivotally connected to a link 40 which is, in turn, operatively connected to the arm 14 of the machine for pivoting the coupler 10 and, thus the bucket 12, about the first axle 34, as well know in the art.
The opposed end portions of the first and second axles 34 and 36 extend laterally outwardly from the side plates 28 for engagement in the hook openings 20 and the cradle openings 24 of the brackets 16, respectively. The second axle 36 is seated in the cradle openings 24.
The quick coupler 10 is provided with a latching mechanism 42 for releasably attaching the quick coupler 10 to the brackets 16 on the bucket 12 after the first and second axles 34 and 36 have been respectively engaged in the hook openings 20 and the cradle openings 24. The latching mechanism 42 comprises a transversal latch bar 44 and an actuator mechanism 46 adapted to be operatively connected to the latch bar 44 for displacing the same between latching and unlatching positions. The latch bar is not actuated by a spring; it may rather be provided as a "dead"
latch bar (i.e. must be operated positively in both directions by the actuator mechanism, it, is not spring loaded or otherwise biased towards a latching position). The latch bar 44 is removably mounted in the guide slots 38 defined in the side plates 28 of the body of the quick coupler 10 and is reciprocable therein along a back and forth direction D for latching and unlatching the quick coupler 10 to the brackets 16 on the bucket 12. The latch bar 44 has opposed wedge-shaped end portions 45 for engagement with corresponding wedge-shaped latching notches 22 (Fig. 1). As best shown in Fig.
3, each wedge-shaped end portion 45 has a top surface which slopes downwardly in the latching direction for mating engagement with the downwardly facing surface of the latching notches 22 defined in the brackets 16.
As shown in Figs. 3 and 4, the actuator mechanism 46 may comprise a pair of double-acting hydraulic cylinders 48, 50. The hydraulic cylinders 48 and 60 may be operatively coupled to any suitable power system adapted to provide hydraulic fluid pressure. For instance, cylinders 48 and 50 could be operatively connected to an independent source of hydraulic fluid pressure or directly connected to the hydraulic system of the earth working machine.
As shown in Fig. 4, each double-acting cylinder 48, 50 has a barrel 52 and a piston 54 slidably mounted in the barrel 52 for reciprocating movement therein. Each piston 54 has first and second opposed sides 56 and 58. A piston rod 60 extends from the second side 58 of each piston 54. Each piston rod 60 has a distal end 62 which extends outside of the barrel 52 for engagement in an elongated slot 64 (Fig.
3) defined in the latch bar 44. As shown in Fig. 3, a pin 66 having a threaded distal end portion for engagement with a nut 67 may be used to pivotally and detachably connect the distal end 62 of each piston rod 60 to the latch bar 44. As can be appreciated from Fig. 3, the points of connection of the hydraulic cylinders 48 and 50 to the latch bar 44 are disposed inboard of the wedge-shaped end portions 45 and adjacent thereto.
Referring back to Fig. 4, it can be seen that first and second inlet ports 68 and 70 are provided at opposed ends of each barrel 52 for allowing the working fluid from the power system to act alternately on both sides of the pistons 54. In this way, the pistons 54 can be displaced under fluid pressure in both a latching direction (the left hand side on Fig. 4) to draw the latch bar 44 in engagement with the latching notches 22 of the brackets 16 and an unlatching direction (the right hand side on Fig.
4) to push the wedge-shaped end portions 45 of the latch bar 44 out of the latching notches 22. The double-acting cylinders 48, 50 thus provide both the latching and the unlatching forces.
As shown in Fig. 1, the quick coupler 10 is pivotally connected to the arm 14 of the earth working machine by the first axle 34. The second axle 36 of the coupler 10 is pivotally connected to a link 40 which is, in turn, operatively connected to the arm 14 of the machine for pivoting the coupler 10 and, thus the bucket 12, about the first axle 34, as well know in the art.
The opposed end portions of the first and second axles 34 and 36 extend laterally outwardly from the side plates 28 for engagement in the hook openings 20 and the cradle openings 24 of the brackets 16, respectively. The second axle 36 is seated in the cradle openings 24.
The quick coupler 10 is provided with a latching mechanism 42 for releasably attaching the quick coupler 10 to the brackets 16 on the bucket 12 after the first and second axles 34 and 36 have been respectively engaged in the hook openings 20 and the cradle openings 24. The latching mechanism 42 comprises a transversal latch bar 44 and an actuator mechanism 46 adapted to be operatively connected to the latch bar 44 for displacing the same between latching and unlatching positions. The latch bar is not actuated by a spring; it may rather be provided as a "dead"
latch bar (i.e. must be operated positively in both directions by the actuator mechanism, it, is not spring loaded or otherwise biased towards a latching position). The latch bar 44 is removably mounted in the guide slots 38 defined in the side plates 28 of the body of the quick coupler 10 and is reciprocable therein along a back and forth direction D for latching and unlatching the quick coupler 10 to the brackets 16 on the bucket 12. The latch bar 44 has opposed wedge-shaped end portions 45 for engagement with corresponding wedge-shaped latching notches 22 (Fig. 1). As best shown in Fig.
3, each wedge-shaped end portion 45 has a top surface which slopes downwardly in the latching direction for mating engagement with the downwardly facing surface of the latching notches 22 defined in the brackets 16.
As shown in Figs. 3 and 4, the actuator mechanism 46 may comprise a pair of double-acting hydraulic cylinders 48, 50. The hydraulic cylinders 48 and 60 may be operatively coupled to any suitable power system adapted to provide hydraulic fluid pressure. For instance, cylinders 48 and 50 could be operatively connected to an independent source of hydraulic fluid pressure or directly connected to the hydraulic system of the earth working machine.
As shown in Fig. 4, each double-acting cylinder 48, 50 has a barrel 52 and a piston 54 slidably mounted in the barrel 52 for reciprocating movement therein. Each piston 54 has first and second opposed sides 56 and 58. A piston rod 60 extends from the second side 58 of each piston 54. Each piston rod 60 has a distal end 62 which extends outside of the barrel 52 for engagement in an elongated slot 64 (Fig.
3) defined in the latch bar 44. As shown in Fig. 3, a pin 66 having a threaded distal end portion for engagement with a nut 67 may be used to pivotally and detachably connect the distal end 62 of each piston rod 60 to the latch bar 44. As can be appreciated from Fig. 3, the points of connection of the hydraulic cylinders 48 and 50 to the latch bar 44 are disposed inboard of the wedge-shaped end portions 45 and adjacent thereto.
Referring back to Fig. 4, it can be seen that first and second inlet ports 68 and 70 are provided at opposed ends of each barrel 52 for allowing the working fluid from the power system to act alternately on both sides of the pistons 54. In this way, the pistons 54 can be displaced under fluid pressure in both a latching direction (the left hand side on Fig. 4) to draw the latch bar 44 in engagement with the latching notches 22 of the brackets 16 and an unlatching direction (the right hand side on Fig.
4) to push the wedge-shaped end portions 45 of the latch bar 44 out of the latching notches 22. The double-acting cylinders 48, 50 thus provide both the latching and the unlatching forces.
The first inlet ports 68 of the first and second cylinders 48 and 50 are connected together in parallel via a first feed line 72 having a threaded port 74 for connection with the source of working fluid. Accordingly, cylinders 48 and 50 may be operated in conjunction to jointly displace the latch bar 44 from its latching position to its unlatching position. The conjoint action of the cylinders 48 and 50 adjacent to the points of engagement of the latch bar 44 with the brackets 16 provides a greater unlatching capacity in the event of the latch bar being jammed in the brackets 16. The latch bar 44 is only displaced by the conjoint action of the cylinders 48 and 50. The cylinders 48 and 50 have no biasing force to overcome to displace the latch bar 44 from the latching position to the unlatching position.
The second inlet ports 70 of the cylinders 48, 50 are also interconnected in parallel via a second feed line 76. The second feed line 76 has a threaded inlet port 78 for connection to the source of working fluid. Accordingly, fluid pressure can flow through the second inlet ports 70 of the cylinders 48 and 50 for allowing the same to jointly draw the latch bar 44 in its latching position. A safety mechanism, such as valve 80, may be provided to ensure that a latching force is maintained on the latch bar 44 in the event of a malfunction or shut down of the power/fluid pressure system (e.g. hydraulic system). For instance, the valve 80 may consist of the load holding/motion control valve manufactured under Model CBCH-LJN by Sun Hydraulics Corporation. According to the illustrated embodiment, the body of the valve 80 is integrated to the barrel 52 of first cylinder 48 and is operatively coupled to the second inlet port 70 of the first cylinder 48 to automatically close the second inlet port 70 thereof in response to a drop of pressure in the hydraulic system. The default position of the valve is closed. Accordingly, when there is no pressure in the system, the valve 80 is closed, thereby preventing the rod 60 of the cylinder 48 from being drawn out of the barrel 52. The valve 80 is connected to the fluid pressure system on the piston side of the cylinders via line 72 and on the rod side via line 76.
The fluid pressure on the piston side opens the valve 80. If the pressure on the rod side exceeds a predetermined value which is greater than the pressure required for holding the latch in its latching position, the valve 80 will open to protect the components of cylinder 48. The value at which the valve opens is adjustable. If the pressure in line 72 drops the valve falls back to its original closed position. When the valve 80 is closed, the working fluid contained in the chamber defined by the barrel 52 of the first cylinder 48 and the piston rod side 58 of the piston 54 is trapped in the barrel 52, thereby holding the first cylinder 48 in a retracted latching position. It is noted that the second cylinder 50 could also be provided with a fail-safe valve to maintain the piston rod 60 in a retracted latching position when the pressure in the system is less than a predetermined threshold value.
Referring back to Fig. 3, it can bee seen that the two cylinders 48 and 50 may be mounted to a common front mounting plate 82 to form a unitary cartridge.
The cartridge can be front loaded in the quick coupler 10 via an opening 84 defined in the front plate 32 of the body of the quick coupler 10. The common front mounting plate 82 of the cartridge can be bolted or otherwise suitably attach to the front plate 32 of the coupler body. By integrating all the parts of the actuator mechanism into a single cartridge, only one physical part has to be mounted to the quick coupler 10.
The actuator mechanism can thus be easily and rapidly installed and replaced.
With such a front-loaded cartridge system, there is no need to remove the quick coupler 10 from the power operated arm 14 of the machine when it is desired to replace the actuator mechanism of the latch bar 44.
After the cartridge has been front loaded and secured to the body 26 of the quick coupler 10, the installation of the latching mechanism can be completed by retracting the piston rods 60 of the cylinders 48 and 50, transversally inserting the latch bar 44 through the guide slots 38, extending the piston rods 60 to engage the distal end portions 62 thereof in slots 64 and by then attaching the latch bar 44 to the distal end portions 62 of the cylinders 48 and 50 with the pins 66 and nuts 67, as shown in Fig. 3.
The above description is meant to be exemplary only, and one skilled in the art will recognize that changes may be made to the embodiments described without departing from the scope of the invention disclosed. For example, while the actuator mechanism has been described as including a pair of hydraulic cylinders, it is understood that other types of actuators could be used as well. For instance, pneumatic cylinders, solenoids, worm mechanisms, and ratchet mechanisms could be used as well. It is also understood that more than two linear actuators could be used to jointly displace the latch bar. It is also understood that the fail-safe valve could be replaced with other suitable safety blocking device for maintaining the latch bar in its latching position in the event of the malfunction of the power system. The type of blocking device will vary with the type of actuators used to displace the latch bar.
Still other modifications which fall within the scope of the present invention will be apparent to those skilled in the art, in light of a review of this disclosure, and such modifications are intended to fall within the appended claims.
The second inlet ports 70 of the cylinders 48, 50 are also interconnected in parallel via a second feed line 76. The second feed line 76 has a threaded inlet port 78 for connection to the source of working fluid. Accordingly, fluid pressure can flow through the second inlet ports 70 of the cylinders 48 and 50 for allowing the same to jointly draw the latch bar 44 in its latching position. A safety mechanism, such as valve 80, may be provided to ensure that a latching force is maintained on the latch bar 44 in the event of a malfunction or shut down of the power/fluid pressure system (e.g. hydraulic system). For instance, the valve 80 may consist of the load holding/motion control valve manufactured under Model CBCH-LJN by Sun Hydraulics Corporation. According to the illustrated embodiment, the body of the valve 80 is integrated to the barrel 52 of first cylinder 48 and is operatively coupled to the second inlet port 70 of the first cylinder 48 to automatically close the second inlet port 70 thereof in response to a drop of pressure in the hydraulic system. The default position of the valve is closed. Accordingly, when there is no pressure in the system, the valve 80 is closed, thereby preventing the rod 60 of the cylinder 48 from being drawn out of the barrel 52. The valve 80 is connected to the fluid pressure system on the piston side of the cylinders via line 72 and on the rod side via line 76.
The fluid pressure on the piston side opens the valve 80. If the pressure on the rod side exceeds a predetermined value which is greater than the pressure required for holding the latch in its latching position, the valve 80 will open to protect the components of cylinder 48. The value at which the valve opens is adjustable. If the pressure in line 72 drops the valve falls back to its original closed position. When the valve 80 is closed, the working fluid contained in the chamber defined by the barrel 52 of the first cylinder 48 and the piston rod side 58 of the piston 54 is trapped in the barrel 52, thereby holding the first cylinder 48 in a retracted latching position. It is noted that the second cylinder 50 could also be provided with a fail-safe valve to maintain the piston rod 60 in a retracted latching position when the pressure in the system is less than a predetermined threshold value.
Referring back to Fig. 3, it can bee seen that the two cylinders 48 and 50 may be mounted to a common front mounting plate 82 to form a unitary cartridge.
The cartridge can be front loaded in the quick coupler 10 via an opening 84 defined in the front plate 32 of the body of the quick coupler 10. The common front mounting plate 82 of the cartridge can be bolted or otherwise suitably attach to the front plate 32 of the coupler body. By integrating all the parts of the actuator mechanism into a single cartridge, only one physical part has to be mounted to the quick coupler 10.
The actuator mechanism can thus be easily and rapidly installed and replaced.
With such a front-loaded cartridge system, there is no need to remove the quick coupler 10 from the power operated arm 14 of the machine when it is desired to replace the actuator mechanism of the latch bar 44.
After the cartridge has been front loaded and secured to the body 26 of the quick coupler 10, the installation of the latching mechanism can be completed by retracting the piston rods 60 of the cylinders 48 and 50, transversally inserting the latch bar 44 through the guide slots 38, extending the piston rods 60 to engage the distal end portions 62 thereof in slots 64 and by then attaching the latch bar 44 to the distal end portions 62 of the cylinders 48 and 50 with the pins 66 and nuts 67, as shown in Fig. 3.
The above description is meant to be exemplary only, and one skilled in the art will recognize that changes may be made to the embodiments described without departing from the scope of the invention disclosed. For example, while the actuator mechanism has been described as including a pair of hydraulic cylinders, it is understood that other types of actuators could be used as well. For instance, pneumatic cylinders, solenoids, worm mechanisms, and ratchet mechanisms could be used as well. It is also understood that more than two linear actuators could be used to jointly displace the latch bar. It is also understood that the fail-safe valve could be replaced with other suitable safety blocking device for maintaining the latch bar in its latching position in the event of the malfunction of the power system. The type of blocking device will vary with the type of actuators used to displace the latch bar.
Still other modifications which fall within the scope of the present invention will be apparent to those skilled in the art, in light of a review of this disclosure, and such modifications are intended to fall within the appended claims.
Claims (21)
1. A quick coupler for detachably coupling a work implement to a power operated arm of an earth working machine, the work implement having a pair of brackets for engagement with the quick coupler, the brackets having a pair of wedge-shaped latching notches; the quick coupler comprising a body adapted to be mounted to a distal end of the power operated arm, the body of the quick coupler being configured for engagement between the brackets on the work implement, a transversal latch bar mounted to the body of the quick coupler, the transversal latch bar having opposed wedge-shaped end portions configured for mating engagement with respective ones of said wedge-shape latching notches of the brackets on the work implement, and a pair of actuators mounted to said body and connectable to a power system for jointly reciprocating said transversal latch bar back and forth between a latching position, wherein the opposed wedge-shaped end portions of the transversal latch bar are engaged in respective ones of the wedge-shaped latching notches of the brackets, and an unlatching position, wherein the opposed wedge-shaped end portions of the transversal latch bar are disengaged from the latching notches, the actuators being mounted side-by-side and connected to the transversal latch bar at locations adjacent to the opposed wedge-shaped end portions thereof, the actuators acting in conjunction to selectively provide both a latching force and an unlatching force, at least one of the actuators being coupled to a safety blocking device which is responsive to a malfunction or shut down of the power system to automatically block said at least one of the actuators in a position in which the at least one of the actuators maintains its latching force on the transverse latch bar.
2. A quick coupler as defined in claim 1, wherein said transversal latch bar is only displaced by the conjoint action of said pair of actuators, the actuators having no biasing force to overcome to displace the latch bar from the latching position to the unlatching position.
3. A quick coupler as defined in claim 1, wherein the pair of actuators comprises first and second hydraulic cylinders, and wherein the safety blocking device comprises a valve responsive to a pressure drop in the power system, thereby maintaining said one of said first and second hydraulic cylinders pressurized in the event of a malfunction of the power system.
4. A quick coupler as defined in claim 1, wherein said pair of actuators comprises first and second double-acting cylinders, each of said first and second double-acting cylinders comprising a barrel and a piston mounted inside the barrel for reciprocating movement therein, the barrel and the piston defining first and second fluid pressure chambers, said first and second fluid pressure chambers being respectively provided with first and second inlets for allowing fluid pressure to act on both sides of the piston, wherein fluid pressure is directed into said first inlet of said first chamber of both said first and second double-acting cylinders to displace the transversal latch bar towards its latching position, and wherein said safety blocking device comprises a valve operatively connected to said first inlet of one of said first and second double-acting cylinders for preventing fluid pressure from escaping from the first chamber of said one of said first and second double acting cylinders in the event of a malfunction.
5. A quick coupler as defined in claim 4, wherein the sides of the piston includes first and second sides, the piston having a piston rod extending from said first side thereof, the piston rod extending axially through said first chamber, the piston rod having a distal end portion extending outwardly from the barrel, the distal end portion of the piston of each said first and second double-acting cylinders being pivotally connected to the transversal latch bar, and wherein the transversal latch bar is drawn to its latching position by both the first and second double-acting cylinders during a retract stroke thereof.
6. A quick coupler as defined in claim 1, wherein said pair of actuators are mounted to a common mounting plate, the actuators and the mounting plate being detachably mounted all together as a unitary actuator block to the body of the quick coupler.
7. A quick coupler as defined in claim 6, wherein said body has a front face defining a front opening for allowing said unitary actuator block to be front loaded into the body, the mounting plate of the unitary actuator block being detachably connected to the front face of the body.
8. A quick coupler as defined in claim 6, wherein said safety blocking device is integrated to said at least one of said pair of actuators.
9. A quick coupler as defined in claim 1, wherein said pair of actuators are provided as linear actuators selected from the group consisting of: a hydraulic cylinder, a pneumatic cylinder, a solenoid, a worm mechanism, and a ratchet mechanism.
10. A quick coupler for detachably coupling a work implement to a power operated arm of an earth working machine, the work implement having a bracket arrangement for engagement with the quick coupler, the bracket arrangement having a latching notch; the quick coupler comprising a body adapted to be mounted to a distal end of the power operated arm, the body of the quick coupler being configured for engagement with the bracket arrangement on the work implement, a dead latch bar mounted to the body of the quick coupler, the dead latch bar configured for mating engagement with the latching notch of the bracket arrangement on the work implement, a pair of double-acting actuators mounted to said body and connectable to a power system for jointly displacing said dead latch bar between a latching position, wherein the dead latch bar is engaged in the latching notch of the bracket arrangement, and an unlatching position, wherein the dead latch bar is disengaged from the latching notch, the double-acting actuators selectively providing both latching and unlatching forces, and a fail-safe mechanism for blocking movement of at least one of said double-acting actuators in the event of a malfunction of the power system while the double-acting actuators are holding the dead latch bar in its latching position.
11. A quick coupler as defined in claim 10, wherein the pair of double-acting actuators consists of a pair of hydraulic cylinders, and wherein said fail-safe mechanism comprises a valve responsive to a pressure drop in a feed line of the hydraulic cylinders for preventing loss of hydraulic fluid pressure in at least one of the hydraulic cylinders.
12. A quick coupler as defined in claim 11, wherein the valve has a default closed position when the power system is down, the valve being opened by fluid pressure generated by the power system during normal operating conditions.
13. A quick coupler as defined in claim 12, wherein each hydraulic cylinder has a barrel and a piston mounted for reciprocating movement inside the barrel, the piston cooperating with the barrel to define first and second chambers, said first and second chambers being respectively provided with first and second inlets for allowing fluid pressure to alternatively act on both sides of the piston, the fluid pressure in the first chamber of the hydraulic cylinders being used to displace and hold the dead latch bar in its latching position, and wherein the valve is operatively connected to the first inlet of the at least one of the hydraulic cylinders to selectively close said first inlet and maintain the fluid pressure in said first chamber.
14. A quick coupler as defined in claim 10, wherein the pair of double-acting actuators are carried by a common mounting plate, and wherein the common mounting plate is adapted to be bolted to the body of quick coupler.
15. A quick coupler as defined in claim 14, wherein the body has a front face defining an opening, and wherein said double-acting actuators are front loaded into the body of the quick couple via said opening with said common mounting plate bearing against said front face.
16. A latching mechanism for securing a quick coupler to a work tool, the quick coupler being mounted to a distal end of an arm of an earth working machine;
the latching mechanism comprising a cartridge removably insertable into a body of the quick coupler, the cartridge comprising a pair of side-by-side actuators extending from a common mounting plate adapted to be detachably secured to the body of the quick coupler, thereby providing for the simultaneous mounting of the side-by-side actuators to the body of the quick coupler by the attachment of the common mounting plate to the quick coupler.
the latching mechanism comprising a cartridge removably insertable into a body of the quick coupler, the cartridge comprising a pair of side-by-side actuators extending from a common mounting plate adapted to be detachably secured to the body of the quick coupler, thereby providing for the simultaneous mounting of the side-by-side actuators to the body of the quick coupler by the attachment of the common mounting plate to the quick coupler.
17. A latching mechanism as defined in claim 16, wherein the cartridge is front loaded into the body of the quick coupler through an opening provided in a front face thereof, the common mounting plate of the cartridge being attachable to said front face.
18. A latching mechanism as defined in claim 16, wherein said pair of side-by-side actuators consists of first and second hydraulic cylinders, and wherein a fail-safe valve is integrated to at least one of said first and second hydraulic cylinders.
19. A latching mechanism as defined in claim 18, wherein the fail-safe valve is mounted in a housing mounted to a barrel of the first hydraulic cylinder.
20. A latching mechanism as defined in claim 18, wherein the first and second hydraulic cylinders each have a piston slidably mounted in a barrel, the piston having a piston rod which extends through a hole defined in the mounting plate.
21. A latching mechanism as defined in claim 18, wherein said first and second hydraulic cylinders have respective inlets interconnected in fluid flow communication.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2727324 CA2727324A1 (en) | 2011-01-10 | 2011-01-10 | Latching mechanism for a quick coupler |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2727324 CA2727324A1 (en) | 2011-01-10 | 2011-01-10 | Latching mechanism for a quick coupler |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2727324A1 true CA2727324A1 (en) | 2012-07-10 |
Family
ID=46491857
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2727324 Abandoned CA2727324A1 (en) | 2011-01-10 | 2011-01-10 | Latching mechanism for a quick coupler |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2727324A1 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IT201700071488A1 (en) * | 2017-06-27 | 2018-12-27 | COUPLING DEVICE | |
| EP3572588A1 (en) * | 2018-05-10 | 2019-11-27 | Verachtert Nederland B.V. | Worktool coupler |
| GB2582595A (en) * | 2019-03-27 | 2020-09-30 | Caterpillar Work Tools Bv | Quick coupler for attaching a tool to a hydraulic excavator or other work machine |
| US10808375B2 (en) | 2014-12-22 | 2020-10-20 | Husqvarna Ab | Implement coupling device and a machine provided with such a device |
| BE1028952B1 (en) * | 2021-04-01 | 2022-07-19 | Warzee Michel | Attachment coupling system for agricultural vehicles |
| GB2613201A (en) * | 2021-11-29 | 2023-05-31 | Caterpillar Work Tools Bv | Coupling device for releasably coupling a tool to a work machine |
-
2011
- 2011-01-10 CA CA 2727324 patent/CA2727324A1/en not_active Abandoned
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10808375B2 (en) | 2014-12-22 | 2020-10-20 | Husqvarna Ab | Implement coupling device and a machine provided with such a device |
| IT201700071488A1 (en) * | 2017-06-27 | 2018-12-27 | COUPLING DEVICE | |
| EP3421671A1 (en) * | 2017-06-27 | 2019-01-02 | Cangini Benne S.R.L. | Coupling device |
| EP3572588A1 (en) * | 2018-05-10 | 2019-11-27 | Verachtert Nederland B.V. | Worktool coupler |
| GB2582595A (en) * | 2019-03-27 | 2020-09-30 | Caterpillar Work Tools Bv | Quick coupler for attaching a tool to a hydraulic excavator or other work machine |
| WO2020192967A1 (en) | 2019-03-27 | 2020-10-01 | Caterpillar Work Tools B.V. | Quick coupler for attaching a tool to a hydraulic excavator or other work machine |
| GB2582595B (en) * | 2019-03-27 | 2021-04-07 | Caterpillar Work Tools Bv | Quick coupler for attaching a tool to a hydraulic excavator or other work machine |
| BE1028952B1 (en) * | 2021-04-01 | 2022-07-19 | Warzee Michel | Attachment coupling system for agricultural vehicles |
| GB2613201A (en) * | 2021-11-29 | 2023-05-31 | Caterpillar Work Tools Bv | Coupling device for releasably coupling a tool to a work machine |
| WO2023094025A1 (en) * | 2021-11-29 | 2023-06-01 | Caterpillar Work Tools B.V. | Coupling device for releasably coupling a tool to a work machine |
| GB2613201B (en) * | 2021-11-29 | 2023-12-27 | Caterpillar Work Tools Bv | Coupling device for releasably coupling a tool to a work machine |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |
Effective date: 20170111 |