CRUMBER FOR TRENCHER

Abstract

A crumber for a trencher machine is provided, the crumber including a crumber mount for mounting to a crumber boom, and a crumber arm, the crumber arm being mounted to the crumber mount by a linkage, the linkage having a first linkage arm and a second linkage arm, the linkage being arranged to allow rotation of at least one of the linkage arms of at least 75. The crumber mount has at least one edge or surface of the crumber arm, wherein the least one edge or surface of the crumber mount and the complementary edge or surface of the crumber arm abut on each other when the crumber arm is in a lowermost position. In this manner, the crumber arm is supported along an extended length when in the lowermost position.

Claims

1. A crumber for a trencher machine, the crumber comprising: a crumber mount for mounting to a crumber boom, and a crumber arm; the crumber aim being mounted to the crumber mount by a linkage the linkage comprising a first linkage arm and a second linkage arm, the linkage being arranged to allow rotation of at least one of the linkage arms of at least 75.

2. The crumber for a trencher according to claim 1, wherein at least one of the linkage arms is rotatable by between 75 to 120, more preferably from 80 to 110, even more preferably from 85 to 100, even more preferably about 90.

3. The crumber for a trencher according to claim 1, wherein the linkage comprises a first linkage arm pivotally connected to the crumber mount and pivotally connected to the crumber arm, and a second linkage arm pivotally connected to the crumber mount and pivotally connected to the crumber arm.

4. The crumber for a trencher according to claim 1 wherein the linkage comprises a pair of first linkage arms each pivotally connected to the crumber mount and pivotally connected to the crumber arm, and a pair of second linkage arms each pivotally connected to the crumber mount and pivotally connected to the crumber arm.

5. The crumber for a trencher according to claim 1 wherein the crumber arm comprises a first crumber arm side plate and a second crumber arm side plate, the first and second crumber arm side plates being connected to each other.

6. The crumber for a trencher according to claim 5 wherein the two side plates are connected to each other by one or more intermediate connectors.

7. The crumber for a trencher claim 5 wherein the linkage comprises a first proximal linkage arm and a second distal linkage arm, with the second distal linkage arm having a distal end pivotally connected to one of the crumber side plates, the distal end of the second linkage arm being located between the first crumber arm side plate and the second crumber arm side plate.

8. The crumber for a trencher according to claim 5, wherein the crumber arm is movable from a first lowermost position to a second uppermost position, the second distal linkage arm lying approximately parallel to the crumber boom when the crumber arm is in a first lowermost most position.

9. The crumber for a trencher according to claim 5, wherein the first proximal arm is rotatable by at least 75 when the crumber arm is moving from a first lowermost position to a second uppermost position.

10. The crumber for a trencher according to claim 9, wherein the first proximal arm is rotatable by between 75 to 120, or from 80 to 110, or from 85 to 100, or about 90, 0 when the crumber arm is moving from the first lowermost position to the second uppermost position.

11. The crumber for a trencher according to claim 5, wherein the first proximal linkage arm is shorter than the second distal linkage arm.

12. The crumber for a trencher according to claim 1, wherein the crumber mount has at least one edge or surface that is of complementary shape to an edge or surface of the crumber arm, wherein the least one edge or surface of the crumber mount and the complementary edge or surface of the crumber arm abut on each other when the crumber arm is in a lowermost position.

13. A crumber for a trencher, the crumber comprising: a crumber mount for mounting to a crumber boom and a crumber the crumber arm being mounted to the crumber mount by a linkage; the crumber mount having at least one edge or surface that is of complementary shape to an edge or surface of the crumber arm; and wherein the least one edge or surface of the crumber mount and the complementary edge or surface of the crumber arm abut on each other when the crumber arm is in a lowermost position.

14. The crumber for a trencher according to claim 13, wherein the at least one edge or surface of the crumber arm comes into contact with and is supported by the complementary edge or surface of the crumber mount when the crumber arm is in the lowermost position and the crumber arm is supported by the crumber mount along the length of the complementary edge or surface of the crumber mount when the crumber arm is in the lowermost position.

15. The crumber for a trencher according to claim 13, wherein the crumber mount comprises two spaced mount side plates for mounting to the crumber boom, the two spaced side plates being connected together.

16. The crumber for a trencher according to claim 13, wherein the crumber further comprises a biasing means to bias the crumber arm to a lowermost position.

17. The crumber for a trencher according to claim 7 wherein, the second distal linkage arm has a proximal end located between the two spaced crumber mount side plates and a distal end located between the two spaced crumber arm side plates.

18. The crumber for a trencher according to claim 5, wherein the first proximal crumber arm extends at an angle of about 20 to 30, preferably about 25, to the crumber boom when the crumber arm is in a lower most position, and extends at an angle of about 95 to 145, more preferably from 105 to 135, even more preferably from 110 to 125, even more preferably about 115 to the crumber boom, when the crumber arm is an uppermost position.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0030] Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:

[0031] FIG. 1 shows a side view of a crumber for a trencher in accordance with an embodiment of the present invention. In FIG. 1, the crumber arm is in a lowermost position;

[0032] FIG. 2 shows a side view of the crumber shown in FIG. 1, with the crumber arm shown in an uppermost position;

[0033] FIG. 3 shows a perspective view of the crumber shown in FIG. 1, with the crumber being shown apart and in line for assembly;

[0034] FIG. 4 shows a side cross-sectional view of the crumber mount of the crumber shown in FIGS. 1 to 3;

[0035] FIG. 5 shows an end view of the crumber mount shown in FIG. 4;

[0036] FIG. 6 shows a side view of the crumber arm of the crumber shown in FIG. 1;

[0037] FIG. 7 shows a perspective view of the crumber arm shown in FIG. 6;

[0038] FIGS. 8 and 9 show side views of the crumber shown in FIGS. 1 and 2, respectively, with angles of rotation added thereto; and

[0039] FIGS. 10 and 11 show side views of a prior art crumber, with the crumber arm shown in a lowermost position in FIG. 10 and the crumber arm shown in an uppermost position in FIG. 11.

DESCRIPTION OF EMBODIMENTS

[0040] The crumber 10 shown in FIGS. 1 to 3 comprises a crumber mount 12 and a crumber arm 14. The crumber mount 12 has apertures 16, 18 formed therein. The apertures 16, 18 can be placed in line with similar apertures formed in a crumber boom and fasteners, such as fastening pins or bolts, can be passed through the aligned apertures to fix or mount the crumber mount to the crumber boom. The crumber boom 11 is shown in dashed outline in FIG. 1.

[0041] The crumber arm 14 is connected to the crumber mount 12 by means of a linkage. The linkage comprises a first linkage arm 20 and a second linkage arm 22. The first linkage arm 20 comprises a proximal linkage arm and the second linkage and 22 comprises a distal linkage arm. In this regard, the trencher machine is located proximal to end 24 of the crumber mount 12.

[0042] Turning now to FIG. 3, the crumber mount 12 comprises a first crumber mount side plate 26 and a second crumber mount side plate 28. Side plate 26 is spaced from side plate 28. An intermediate support plate 30 is positioned between the side plates 26 and 28. The side plates are provided with openings 32, 34 (see FIG. 1) that receive tabs on the intermediate support plate 32 thereby holding the intermediate support plate 30 in position. Intermediate support plate 30 may be welded to the side plates 26, 28.

[0043] The crumber arm 14 includes first crumber arm side plate 36 and second crumber arm side plate 38. Crumber arm side plates 36 and 38 are spaced from each other. A stiffener 40 is located between the crumber arm side plates 36 and 38 and welded thereto. A scraper plate 42 is welded to the lower end of the crumber arm 14 and acts to rigidly fix the lower end of the crumber arm side plates 36 and 38 together. In use, the lower end of the scraper plate 42 contacts the bottom of the trench and acts to move dirt and debris into close proximity with the trencher boom, thereby facilitating removal of dirt and debris from the trench by the chain and teeth rotating around the trencher boom. In practice, the scraper plate 42 may be fitted with removable feet. The removable feet may be replaced when they are worn. Alternatively, the scraper plate 42 may be hard-faced in order to increase its useful working life. The scraper plate may have one or more points or intensifiers formed at its lower end. The improves operation of the crumber.

[0044] The side plates of the crumber arm 14 are provided with apertures 44 and 46. Similarly, the crumber mount side plates 26, 28 are provided with apertures 48. A linkage arm assembly 50 is connected at its proximal end by a pin that passes through apertures 48 and aligned apertures 52 formed in the linkage arm assembly 50. This connects the proximal end of the linkage arm assembly 50 to the crumber mount side plates 26, 28. Similarly, the linkage arm assembly 50 is connected at its distal end by a pin that passes through apertures 44 in the crumber arm side plates 36, 38 and through an aligned aperture 54 in the distal end of the linkage am assembly 50. This pivotally connects the distal end of the linkage am assembly 50 to the crumber arm 14. It will be appreciated that the linkage arm assembly 50 comprises two spaced second linkage arms 22. In some embodiments, screw button head sockets 64 may be used to fasten the pivotal connections.

[0045] As best shown in FIGS. 1 and 2, the two spaced distal linkage arms 22 are located between the two spaced crumber mount side plates and the two spaced crumber arm side plates. As a result, the two distal linkage arms 22 are located to the inside of the side plates of the crumber mount and the crumber arm. Consequently, the side plates provide a degree of protection to the linkage arms as the linkage arms are not fully exposed to the working environment.

[0046] The crumber mount side plates 26, 28 are each provided with an aperture 56. A screw button head socket 58 passes through an aperture in the proximal end of the first linkage arm 20 and is used to pivotally connect the proximal end of the first linkage arm 14 to the crumber mount side plate 26. A similar arrangement utilising screw button head socket 62 is used to connect another proximal linkage arm to the other crumber mount side plate 28. The distal end of the proximal linkage arms 14 are connected in a similar fashion to the proximal end of the crumber arm side plates 36, 38, with the socket 62 passing through openings in the distal end of the proximal linkage arms 20 and two proximal apertures 46 in the side plates of the crumber arm. In this manner, the proximal linkage arms 14 are pivotally connected to both the crumber mount 12 and the crumber arm 14.

[0047] The crumber arm 14 is biased to the lowermost position shown in FIG. 1. In order to enable this to occur, a biasing spring 64 is fitted over a spring support 66. Spring support 66 is held in place by the pin 68 that forms part of the pivotal connection for the proximal end of the proximal linkage arms 20 to the crumber mount 12. A distal end of a biasing spring 64 extends over the end 70 of the crumber arm 14. A proximal end of the biasing spring 64 rests in recess 72 formed in intermediate support plate 30 that is fitted between the side plates 26, 28 of the crumber mount 14. In this manner, the spring acts to push downwardly on the crumber arm 14, thereby biasing the crumber arm 14 to the lowermost position shown in FIG. 1 in the absence of any external applied force.

[0048] Returning now to FIGS. 1 and 2, the crumber arm 14 can move between the lowermost position shown in FIG. 1 and an uppermost position shown in FIG. 2. During movement of the crumber arm, the linkage arms 20, 22 rotate about the pivotal connections to both the crumber mount 12 and the crumber arm 14. As shown in FIG. 2, the second linkage arm 22 is significantly longer than the first linkage arm 20. Indeed, the second linkage and 22 may be from 1.5 to 2 times longer than the first linkage arm 20, more preferably from 1.75 to 2 times longer than the first linkage arm.

[0049] Turning now to FIGS. 8 and 9, the arrangement and geometry of the crumber 10 results in the first linkage arm 20 extending at an angle of approximately 25 to the longitudinal axis of the crumber boom 11 when the crumber arm 14 is in the lowermost position. This is shown in FIG. 8. The crumber arm 14 may move upwardly to its uppermost position by rotation of both the first linkage arms 20 and the second linkage arms 22 about their respective pivotally connected ends. The arrangement and geometry of the crumber 10 results in the first linkage arms 20 extending an angle of approximately 115 to the longitudinal axis of the crumber when in its uppermost position, as shown in FIG. 9. Therefore, the first linkage arm has rotated by approximately 90.

[0050] FIGS. 10 and 11 show a prior art crumber having a first linkage arm 20A that extends any angle of approximately 33 when the crumber arm 14A is in the lowermost position (see FIG. 10). When the crumber arm 14A is in the uppermost position as shown in FIG. 11, the first linkage arms 20A extend an angle of approximately 100 to the longitudinal axis of the crumber boom. Thus, the first linkage arms have only rotated by approximately 67, significantly less than the rotation of the first linkage arms of the crumber 10 shown in FIGS. 8 and 9. Furthermore, when the crumber arms are in the uppermost position, the lower end of the scraper plate 42A of the prior art crumber shown in FIG. 11 is significantly lower than the lower end of the scraper plate 42 of the crumber 10 shown in FIG. 9.

[0051] By virtue of the crumber arm being able to move to a higher position, excavation of a new trench may commence without the requirement to undo or release the crumber 10 from the crumber boom, as is required with present crumbers. Rather, as the crumber 10 of the present invention can move to a higher uppermost position, the crumber arm 14 can move sufficiently high relative to the trencher blade such that the crumber arm 14 can rest on undisturbed ground whilst the trencher blade moves to the required depth for the trench and the crumber arm can then move down into the trench once the trencher starts to move along the length of the new trench. Thus, it is not necessary to remove the crumber 10 from the crumber boom when commencing a new trench with the crumber of the present invention.

[0052] Returning to FIGS. 1 and 2, it can be seen that the crumber mount side plate 26 is provided with an extended upper edge 74. Indeed, upper edge 74 includes an extended straight edge portion 74. Crumber mount side plate 28 is similarly shaped. The crumber arm side plate 36 is provided with a proximal lower edge 76 that also includes an extended straight portion. When the crumber arm 14 is in its lowermost position, as shown in FIG. 1, the complimentary edges 74, 70 abut on each other such that the edge 76 of the crumber arm 14 lies on the edge 74 of the crumber mount 12. In this manner, the force required to support the crumber arm 14 is distributed along the length of the complimentary edges 74, 76. This acts to minimise the load concentrations between the crumber mount 12 and the crumber arm 14.

[0053] The crumber in accordance with embodiments of the present invention provides a robust crumber having lower wear at contact positions between the crumber mount and the crumber arm. The crumber arm can move upwardly to a significantly larger degree than in prior art crumbers, thereby avoiding the necessity of having to undo at least one of the pins holding the crumber to the crumber boom when excavation of a new trench commences. This, of course, also obviates the requirement to reattach the crumber to the crumber boom once a length of the new trench has been excavated. Thus, the crumber of the present invention provides for significant ease-of-use and increased efficiency.

[0054] In this specification, the term proximal is used to refer to positions located relatively closer to the trencher machine and the word distant is used to refer to positions located relatively farther away from the trencher machine. The terms lowermost and uppermost are used in the context of a position of the crumber arm relative to the crumber boom.

[0055] In the present specification and claims (if any), the word comprising and its derivatives including comprises and comprise include each of the stated integers but does not exclude the inclusion of one or more further integers.

[0056] Reference throughout this specification to one embodiment or an embodiment means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases in one embodiment or in an embodiment in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

[0057] In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims (if any) appropriately interpreted by those skilled in the art.