Work attachment assemblies

Abstract

Improvements to work attachment assemblies and in particular work attachment assemblies for use with work machines such as excavators.

Claims

1. A coupler, comprising: a body; a first jaw that is moveable with respect to the body to engage a first pin on a work attachment; a second jaw that does not move with respect to the body, wherein the second jaw has an opening to a cavity, and wherein the opening is configured to enable a second pin on the work attachment to be inserted into the second jaw; an actuator having a first end and a second end, wherein the first end is connected to the first jaw to enable the actuator to move the first jaw; and a locking mechanism to secure the second pin in the second jaw when inserted therein in use, the locking mechanism comprising a locking portion and a biasing element, wherein the locking portion is moveable to a locking position in which the locking portion at least partially obstructs the opening to the second jaw to prevent the second pin being withdrawn from the second jaw, wherein the locking portion is rigidly fixed with respect to the second end of the actuator so that the locking portion moves through the same path as the second end of the actuator, and further wherein the locking portion does not rotate relative to the second end of the actuator, wherein the biasing element provides an urging force to bias the locking portion towards the locking position, and further wherein the coupler is configured such that contraction of the actuator causes the second end of the actuator to move, thereby also causing the locking portion to move sufficiently so as to enable the second pin to be removed from the second jaw when inserted therein.

2. The coupler in claim 1, wherein a portion of the actuator is shaped to provide the locking portion.

3. The coupler in claim 1, wherein the actuator is mounted in the coupler so that at least the second end of the actuator can move with respect to the body.

4. The coupler in claim 3, comprising a track to guide movement of the second end of the actuator through a pre-determined range of movement.

5. The coupler in claim 4, wherein the track is configured to guide contraction of the actuator to move the locking portion to a release position that allows the second pin to be withdrawn from the second jaw.

6. The coupler in claim 1, wherein the first jaw is configured to slide with respect to the body.

7. The coupler in claim 1, wherein the coupler is configured to secure the second pin in the second jaw regardless of whether the first jaw engages the first pin on the work attachment.

8. The coupler in claim 1, wherein the second jaw provides a front jaw of the coupler.

9. The coupler in claim 1, wherein the second jaw is oriented to face in a direction substantially opposite the first jaw.

10. The coupler in claim 1, wherein the biasing element is a compression spring, and further wherein the compression spring is positioned and configured such that movement of the second end of the actuator to move the locking portion out of the opening of the second jaw compresses the compression spring.

11. The coupler in claim 10, wherein the compression spring is configured to apply an urging force to the locking portion to move it towards a position in which the locking portion at least partially obstructs the opening in the second jaw when hydraulic pressure in the actuator is released.

12. The coupler in claim 9, wherein the first jaw provides a rear jaw of the coupler.

13. The coupler in claim 11, wherein the compression spring is positioned and configured so that force applied to the locking portion by the second pin can overcome the locking portion to move the locking portion sufficiently to enable a pin to be inserted into the second jaw.

14. The coupler in claim 1, wherein the locking mechanism comprises the locking portion which is moveable to the locking position in which it at least partially obstructs the opening to the second jaw.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) 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:

(2) FIG. 1 is an exploded view showing the components of present invention;

(3) FIG. 2 is a side cross-sectional view of a coupler;

(4) FIGS. 3A-N are side cross-sectional schematics showing operation of the coupler;

(5) FIGS. 4A and 4B are a side view showing the safety link in the safety position and release position;

(6) FIGS. 5A and 5B are front and side perspective views of the first and second components of a connection assembly;

(7) FIGS. 6A-F are a side cross-sectional schematic showing operation of a connection assembly;

(8) FIGS. 7 A-7 G are side cross-sectional views of an alternative embodiment of a coupler according to the present invention;

(9) FIG. 8 is an exploded view of components of the alternate embodiment of the coupler; and

(10) FIGS. 9 A & B are view of a tilt bucket having part of a connection assembly according to the present invention secured thereto.

BEST MODES FOR CARRYING OUT THE INVENTION

(11) The present invention relates to improvements to work attachment assemblies (1) for use with excavators (not shown in the drawings). Like numbers refer to like components throughout the Figures.

(12) Referring to FIG. 1 which is an exploded view showing the components of the work attachment assemblies, and FIG. 2 showing a side cross-sectional view of a coupler (2). The components of the coupler (2) will be discussed in the order in which they are assembled.

(13) The coupler (2) has a body (3) to house its components. The body (3) facilitates attachment of the coupler (2) to an excavator arm (not shown). The attachment is via apertures (4) through which fasteners (not shown) can extend. This is as should be known to those skilled in the art.

(14) The body (3) has a first jaw (5) formed integrally at one end (6).

(15) A hydraulic cylinder (8) is positioned within the body (3). A second jaw (7) is secured to the hydraulic cylinder (8) at its first end (9A).

(16) The hydraulic cylinder (8) is configured to slide the second jaw (7) relative to the body (3) by expanding and contracting.

(17) Second end (9B) of the hydraulic cylinder (8) is shaped to form a locking portion (10).

(18) The hydraulic cylinder (8) is floatingly mounted and is able to move within the body (3). This movement is additional to the expansion and contraction of the hydraulic cylinder (8).

(19) A snap lock mechanism (11) is formed from springs (12) and a pin (13). The pin (13) extends through the hydraulic cylinder (8) and into channels (15) in the body (3).

(20) The springs (12) provide a biasing force against the pin (13) and thereby the hydraulic cylinder (8).

(21) Nuts (16) allow the tension of the springs (12) to be adjusted.

(22) Safety links (17) are pivotally mounted to the second jaw (7).

(23) The body (3) has channels having a first section (19) and a second section (20). Stops (29) separate the first and second sections (19, 20).

(24) Each channel (18) has a ridge (21) in the first section (19).

(25) Protrusions (22) extend from the side of the actuator (8) to provide reset portions.

(26) A restricting portion (23) is formed from a recess (24) on the jaw (7), and a spring (25) biased detent (26) in the safety link (17). The restricting portion (23) can be better seen in FIGS. 4A and 4B.

(27) The relevance of the foregoing will become clearer from the following description of the coupler (2) in-use with reference to FIGS. 3 A-N.

(28) An excavator arm manipulates the coupler so that it will engage a work attachment having a first pin (27) and a second pin (28). The first and second pins (27, 28) are parallel.

(29) The first and second pins (27, 28) are shown in the Figures but the work attachment and excavator arm are not shown to simplify the Figures.

(30) The first pin (27) presses against the locking portion (10). This overcomes the springs (12) to move the locking portion (10) and allow the pin (27) into the first jaw (5). Once the pin (27) is sufficiently inside the first jaw (5) the snap lock mechanism (12) forces the locking portion (10) into the locking position. This secures the pin (27) inside the first jaw (5).

(31) The body (3) is tilted to position the second jaw (7) between the first pin (27) and second pin (28).

(32) The hydraulic cylinder (8) expands to slide the second jaw (7) to engage the second pin. This is the position shown in FIG. 3E. The work attachment is now secured to the coupler (2) and can operate as should be known to those skilled in the art.

(33) It should be noted that the safety links (17) do not touch the ridges (21).

(34) To release the work attachment (not shown) the second jaw (7) is moved so that it releases the second pin (28).

(35) The coupling (2) is tilted with respect to the work attachment (not shown). This brings the second jaw (7) out of alignment with the second pin (28). The hydraulic cylinder (8) expands to move the second jaw (5). As the second jaw (7) is not in line with the second pin (28) the hydraulic cylinder can expand past the position in which the second jaw (7) engages the second pin (28).

(36) This movement is in the opposite direction to that in which the second jaw (7) moves to release the second pin (28).

(37) This action causes the safety links (17) to touch the ridges (21). The ridges (21) press against the safety links (17) forcing them into the release position.

(38) FIG. 3I is the same as FIG. 3H but without the hydraulic cylinder (8) shown. This allows the safety links (17) to be clearly seen and that these are in the release position.

(39) The operator sends a signal to the hydraulic cylinder (8) to contract. This moves the second jaw (7) in the opposite direction i.e. the same direction that the second jaw (7) moves to release the second pin (27). The second jaw (7) is moved until the safety links (17) abut the stops (29). This prevents the hydraulic cylinder (8) moving the second jaw (7).

(40) The hydraulic cylinder (8) continues to contract. As the safety links (17) abut the stops (29) this causes the end (9B) of the hydraulic cylinder (8) to move. The path of the end (6) is controlled by the pin (13) travelling in the channels (15). This causes the locking portion (10) to move out of the first jaw (5) thereby releasing the first pin (27) from the first jaw (5).

(41) FIGS. 3K-3N show the hydraulic cylinder in dotted outline.

(42) The safety links (17) therefore cause contraction of the hydraulic cylinder (8) to move the locking portion (10). This releases the first pin (27) from the first jaw.

(43) The coupler (2) can then be moved away from the work attachment.

(44) The protrusions (22) press against to the safety links (17) forcing them to move away from the stops (29) and align with the second section (20) of the channels (18). This allows the hydraulic cylinder (8) to extend thereby forcing the locking portion (10) back into the first jaw (5). This resets the snap lock mechanism.

(45) Referring now to FIGS. 1, 5A and 5B which show the components of a connection assembly (30) to provide a connection between hydraulic actuators on a work attachment and a control system (not shown in the Figures for ease of reference).

(46) The connection assembly (30) is formed from a first component (31) and a second component (32). The first component (31) is mounted on the second jaw (7) of the coupler (2). The second component (32) is mounted on a work attachment as is shown in FIGS. 9A & B.

(47) The first component (31) has a mounting (33) with a plurality of male hose connectors (34). A first guard (35) is pivotally attached to the mounting (33).

(48) A spring (36) biases the first guard (35) to a closed position in which it protects the male connectors (34).

(49) The second component (32) has a mounting (37) in the form of a housing and a second guard (38) slideably attached to the mounting (32). A spring (not shown) biases the second guard (38) to a closed position.

(50) A set of female hose connectors (40) are mounted inside the housing.

(51) The female connectors (40) and male connectors (34) are complementary and can engage each other to provide a connection between the control system and actuators on the work attachment.

(52) The second component (32) has a plate (43) with openings (44). The male connectors (34) can be inserted through the openings (44).

(53) The female connectors (40) have latches (41) which secure the male connectors (34) to them. The latches (40) release the male connectors (33) when moved along the length of the female connector (39).

(54) Referring now to FIGS. 6A-6F which are side schematics showing the connection assembly (30) in use.

(55) The coupler (2) is positioned so that jaw (5) receives pin (27). The coupler (2) is tilted to move the second jaw (7) between pins (27,28). This action causes the coupler (2) to force guard (38) to slide down and expose the female connectors (40).

(56) The action of tilting the coupler (2) between the pins (27, 28) also causes the guard (35) to move thereby exposing the male connectors (34). This is due to member ( ) on the guard (35) contacting a portion on the second component (32). This contact prevents the guard (35) tilting with the coupler (2) so that in effect the guard pivots with respect to the coupler (2) to expose the connectors (34)

(57) The second jaw (7) moves forward causing a corresponding movement in the first component (31).

(58) Tapered members (45) extend into openings (46). The members (45) help to ensure alignment of the hose connectors (34, 40) so that they can engage.

(59) The second jaw (7) continues moving causing the male and female connectors (34, 40) to engage. This provides a connection between a hydraulic cylinder and a control system (neither shown in the FIGS. 6A-6F).

(60) To release the connectors (34,40), the second jaw (7) is moved. This moves the first component (31) away from the second component (32) thereby causing the latches to abut the edges of the openings (44). The latches (39) are moved along the length of the female connector (38) thereby releasing the engaged connectors (34,40).

(61) Springs (36) force the guards (35, 38) back to the closed position. The guards can therefore protect the connectors (34, 40) when not in use.

(62) Referring now to FIGS. 7A-7G, and 8 which show an alternative embodiment of a coupler (46) according to the present invention.

(63) The coupler (46) has a body (47) with a first jaw (48) formed integrally at one end (49). A second jaw (50) is positioned inside the body (47). The second jaw (50) is able to slide with respect to the body (47).

(64) A hydraulic cylinder (51) is floatingly mounted in the body (47). The second jaw (50) is secured to the hydraulic cylinder (51) at its first end (52).

(65) The hydraulic cylinder's second end (53) is shaped to define a locking portion (54).

(66) Torsion springs (55) are mounted in the body (47) and abut against the hydraulic cylinder (51). The torsion springs (55) exert a biasing force that urge the hydraulic cylinder (51) and therefore the locking portion (54), towards a locking position.

(67) The locking portion (54) sits across the entrance (56) to first jaw (48). This is shown in FIG. 7A.

(68) Safety links (57) are pivotally mounted to the body (47) above the second jaw (50). The safety links (57) have protrusions (58).

(69) In use, the coupler (46) is positioned so that a pin (59) presses against the locking portion (54). This overcomes the urging force of the torsion springs (55) and moves the locking portion (54) from the entrance (50) to first jaw (48). This allows the pin (59) to be inserted into the first jaw.

(70) When the pin (59) is inside the jaw (48) the torsion springs (55) force the locking portion (54) back across the entrance (56) to secure the pin inside the first jaw (48).

(71) The coupler (46) is tilted so that second jaw (50) is between pin (59) and a second pin (60).

(72) The hydraulic cylinder (51) is caused to expand which slides the second jaw (50) with respect to the body (47).

(73) The second jaw (50) receives the second pin (60) and thereby secures the work attachment (not shown) to the coupler (40). The work attachment can then be used as per normal operation.

(74) To release the work attachment (not shown) the hydraulic cylinder (51) is caused to contract. This slides the second jaw (50) with respect to the body to release the second pin (60).

(75) The coupler (46) is tiled so that the second jaw (51) is brought of alignment with the second pin (60).

(76) The hydraulic cylinder (51) is caused to expand to move the second jaw (50) past the position in which it engages the second pin (60). This causes the second jaw (50) to move so that edge (61) is past the protrusions (58). This allows the safety links (57) to pivot downward. In this position the protrusions (58) are no longer above the top (62) of the jaw (50).

(77) The hydraulic cylinder (51) contracts causing edge (61) to abut protrusions (58). This prevents first end (52) and the second jaw (50) moving further within the body (47).

(78) The hydraulic cylinder (51) continues to contract. As the hydraulic cylinder (51) is floatingly mounted within the body (47) the second end (53) is moved. This causes the locking portion (54) to be moved away from entrance (56) to the first jaw (48). First pin (59) therefore is released from the first jaw (56) and therefore the coupler (46).

(79) The coupler (46) can be moved away from the work attachment (not shown).

(80) Hydraulic cylinder (51) continues to contract. Safety links (57) abut against detents (63). This lifts the safety links (57) above edge (61) of the second jaw (50). The torsions springs ( ) force the locking portion (54) across entrance (56) to the first jaw (48). This allows hydraulic cylinder (51) to expand slightly towards the first jaw (50). Simultaneously the protrusions (58) are again above the top (64) of second jaw (50). This resets the safety links (57) to the safety position.

(81) Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof.

(82) Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims.