AU716828B2

AU716828B2 - A wedging device

Info

Publication number: AU716828B2
Application number: AU75357/96A
Authority: AU
Inventors: David John Chesterfield
Original assignee: Ani Corp Ltd
Current assignee: Bradken Resources Pty Ltd
Priority date: 1995-12-22
Filing date: 1996-12-12
Publication date: 2000-03-09
Anticipated expiration: 2016-12-12
Also published as: AU7535796A

Description

1- P/00/0 11 Regulation 3.2

AUSTRALIA

Patents Act 1 990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Invention Title: "A Wedging Device" 4* t

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.The following statement is a full description of this invention, including the best method of performing it known to us: GH REF: P24169K/DAA:WW 2 FIELD OF THE INVENTION The present invention relates to a wedging device for fixing an attachment to a support means. The device is particularly suitable for fixing an attachment to mining or landscaping equipment wherein the attachment is subjected to substantial stresses during use.

BACKGROUND OF THE INVENTION It is known to use a spool and wedge to fix an adaptor carrying a sacrificial wear part to a dragline bucket.

The adaptor is firstly fitted onto a dedicated nose portion of the dragline bucket and the spool is then inserted into a passageway formed through the adaptor and the nose portion. Subsequently, the wedge is inserted into the passageway between the spool and a tip region of the nose portion before being driven into the passageway with the aid of a sledge hammer. The insertion of the wedge causes the spool to move rearwardly thereby forcing the adaptor tightly onto the nose portion.

However, the insertion of the spool and wedge into the passageway is complicated by the fact that they exist as separate parts. Moreover, the wedge can misalign in the passageway if not driven in correctly with the sledge hammer.

Removing the wedge from the passageway can also be difficult and it may be necessary to dislodge the wedge by first striking it and then rocking it back and forth relative to the spool until it is free. This can be time consuming which is undesirable.

A wedging device consisting of a spool and a separate wedge assembly comprising two wedges is disclosed in Australian patent application No 68677/94.

A bolt extends through a passageway formed in one of the wedges and engages with a thread formed in the other 35 wedge. In use, the spool and wedge assembly is positioned in the passageway formed through the adaptor and the nose portion of the dragline bucket as described above. When the bolt is rotated the wedges are drawn S:24169K toward each other are moved up inclined surfaces formed on the spool into contact with the nose portion of the dragline bucket causing the spool to be forced against the adaptor and resulting in the adaptor being drawn onto, and fixed to, the nose portion. However, as the bolt is rotated it is drawn into the passageway such that access to the head of the bolt is diminished.

Moreover, as the wedging device is comprised of separate spool and wedge assembly components, it is necessary to hold the component together in alignment as the device is being positioned in the passageway.

Due to the size of dragline buckets as well as the nature of the forces exerted on them during use, the wedging device is correspondingly large and may weigh six kilograms or more making it difficult to hold the components together during installation which poses a safety risk.

nSUMMARY OF THE INVENTION In a first aspect of the present invention there is provided a wedging device locatable between an adaptor or tooth base and a nose portion of an excavator bucket, said wedging device comprising: oa spool; a wedge in contact with the spool; and a rotatable member received by the wedge and the spool; wherein the spool is adapted to restrain the i: rotatable member from moving toward the wedge during rotation of the rotatable member in a first direction, and wherein the rotation of the rotatable member in the first direction causes the wedge to be drawn along the spool and be pressed against the adaptor or tooth base to thereby force the spool against the nose portion of the excavator bucket or vice versa, when the wedging device is located between the adaptor or tooth base and said nose portion.

By restraining movement of the rotatable member along the device toward the wedge when rotated in the first -4direction, the rotatable member is held in a desired position during installation of the device and accessibility of the rotatable member to a workperson is maintained.

The device may also have means for restraining movement of the rotatable member away from the wedge when rotated in an opposite second direction to thereby cause the wedge to withdraw from between the adaptor or tooth base and said nose portion and so facilitate removal of the device.

Preferably, the wedging device is provided with tensioning means for maintaining tension on the rotatable member to retain the wedge in position between the adaptor or tooth base and said nose portion.

In a second aspect of the invention there is provided a kit for the wedging device. The kit may contain the spool, the wedge and the rotatable member of the device.

In a third aspect of the invention there is provided an assembly comprising the wedging device and the adaptor 20 or tooth base and said nose portion, wherein the adaptor or tooth base and said nose portion have openings which align to form a passageway and wherein the mounting device is arranged in the passageway such that the wedge is pressed against the adaptor or tooth base and the spool is in 25 contact with the nose portion of the excavator bucket.

Embodiments of the invention may be used, for example, to fix an adaptor to a nose portion of a dragline bucket.

It will be appreciated, however, that embodiments may also "5 be used for fixing together other components of excavating or similar equipment which are subject to substantial forces during use.

The wedge and spool of the wedging device may be formed from any high strength material such as steel.

Moreover, embodiments may be manufactured using any conventional machining or casting techniques.

Advantageously, the wedging device can remain as a L' ingle cohesive assembly during all phases of operation ingle cohesive assembly during all phases of operation 31109 -4a facilitating insertion of the wedging device between, and withdrawal from, the two components.

It is another advantage that in an embodiment, the wedge can be guided by the spool when the rotatable

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i member is rotated thereby avoiding the possibility of misalignment of the wedge during installation of the device.

The present invention will be further described hereinafter with reference to preferred, non-limiting embodiments illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an exploded perspective view of a wedging device embodied by the present invention; Figure 2 is an exploded perspective view of an adaptor and a nose portion of a dragline bucket; Figure 3 is a side view of a dragline bucket; and Figure 4 is a cross-sectional side view of the adaptor and nose portion of Figure 2 fixed together with a wedging device of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION The wedging device illustrated in Figure 1 is comprised of a spool 1 and a wedge 2. Spool 1 is provided with an inclined surface 3 and an aperture 4 through which bolt 5 is able to be inserted so as to extend into channel 6.

When assembled, inclined surface 7 of wedge 2 rests

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on inclined surface 3 of spool 1 in face-to-face contact, and bolt 5 is received in receiving portion 8 which *.":protrudes from the wedge into channel 6.

Receiving portion 8 of wedge 2 is provided with a female thread which engages with male thread 9 of bolt Accordingly, wedge 2 is drawn along inclined surface 3 of 30 spool 1 when the bolt is rotated by virtue of the engagement of the threads and is guided by the reception of receiving portion 8 in channel 6.

As the head 10 of bolt 5 is received in recess 11 of spool i, the bolt is restrained by wall 12 from being 35 drawn along the spool toward wedge 2 during the rotation of the bolt.

Moreover, bolt 5 is restrained from moving away from the wedge when rotated in an opposite direction by stop S:24169K 6 means in the form of a circlip 13 received in groove 14 of bolt 5. In use, circlip 13 is located in channel 6 and prevents movement of the bolt away from wedge 2 by abutting wall 12 of the spool.

The embodiment shown in Figure 1 is also provided with tensioning means in the form of a spring washer for maintaining tension on bolt 5. The washer is sized to be received in recess 11 between head 10 of bolt 5 and wall 12 of the spool.

As described above, the wedging device may be used to fix an adaptor to the nose portion of a dragline bucket. An adaptor 16 and a nose portion 17 of a dragline bucket are illustrated in Figure 2. Adaptor 16 has a tip region 18 formed to receive a sacrificial wear part (not shown). The sacrificial wear part is fitted on tip region 18 by a bolt which passes through aperture 19.

A dragline bucket 20 is illustrated in Figure 3. A plurality of adaptors 16 having sacrificial wear parts 21 are spaced apart along the front of the base of the dragline bucket and dig into ore, for instance, when the bucket is dragged across the ore body as will be readily appreciated by the skilled addressee.

The operation of the wedging device of the invention will now be described with reference to Figure 4. As shown in the figure, upper and lower surfaces 22 and 23 of adaptor 16 have openings 24 and 25 which align with openings 26 and 27 of nose portion 17 to form a passageway 28 in which the wedging device is inserted.

The wedging device is arranged in passageway 28 such that the faces of end regions 29 of spool 1 bear against surfaces 30 of adaptor 16. Shoulders 31 of the spool assist to maintain the wedging device in position within the passageway.

In order to fix adaptor 16 to nose portion 17, bolt 35 5 is screwed into receiving portion 8 of wedge 2 causing the wedge to be drawn into passageway 28 along inclined surface 3 of spool i.

As the bolt is rotated, contact surface 32 of the S:24169K 7 wedge is pressed into face-to-face contact with reaction surface 33 of tip region 34 of nose portion 17, forcing the faces of end regions 29 of spool 1 against surfaces of adaptor 16 and thereby causing the adaptor to be moved rearwardly onto the nose portion. With continued rotation of the bolt the wedge is drawn further into passageway 28 resulting in adaptor 16 being fixedly secured to nose portion 17 of dragline bucket The wedging device is adapted such that wedge 2 is first brought to bear against the middle area of reaction surface 33 and so a force is exerted on the tip region in a direction substantially perpendicular to both reaction surface 33 and the longitudinal axis of the device to reduce the possibility of adaptor 16 becoming misaligned on the nose portion 17 as it is forced rearwardly.

Moreover, since bolt 5 is prevented from being drawn toward wedge 2 by wall 12 of spool 1, the head 10 of the bolt remains readily accessible at the opening of passageway 28 to a workperson.

In order to remove adaptor 16 from nose portion 17, bolt 5 is rotated in an opposite direction. Because the bolt is restrained from moving away from wedge 2 by the contact of circlip 13 (not shown in Figure 4) with wall 12 of spool 1, the wedge is drawn away from the reaction surface 33 of tip region 34 by virtue of the engagement of thread 9 of the bolt with receiving portion 8 of the wedge. The wedging device is then able to be withdrawn from passageway 28 and the adaptor dislodged from nose portion 17.

S 30 In addition, since bolt 5 extends through aperture 4 of spool 1 and engages with the thread formed on wedge 2, S: the wedging device is maintained in the form of a single cohesive assembly while being inserted into, fixed in position within, and removed from passageway 28.

35 While the wedging device illustrated in the accompanying drawings is designed so that wedge 2 presses against tip region 34 of nose portion 17, and spool 1 presses against adaptor 16, embodiments may be provided S:24169K 8 wherein the wedge is adapted to press against the adaptor while the spool is adapted to press against the nose portion.

Moreover, it will be appreciated by the skilled addressee that while bolt 5 is shown in the accompanying drawings as lying in channel 6 of spool 1, an embodiment may be provided wherein the bolt lies within a channel formed within the wedge. In this instance, the bolt may protrude from the spool into the channel of the wedge and be screwed into an aperture defined in the wedge to cause the wedge to be drawn along the inclined surface of the spool when the bolt is rotated.

Embodiments of the present invention may be provided as a single cohesive assembly or in kit form. A kit may, for instance, comprise spool i, wedge 2, bolt 5, spring washer 15 and circlip 13. If desired, adaptor 16 and/or nose portion 17 may also be provided in the kit.

Although the present invention has been described hereinbefore with reference to preferred embodiments, numerous variations and modifications are possible without departing from the scope of the invention which is defined in the following claims.

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Claims

2. A wedging device according to claim 1 wherein the rotatable member has means for restraining movement of the rotatable member away from the wedge when the rotatable member is rotated in an opposite second direction, said restraining means together with the rotatable member thereby effecting movement of the wedge along the spool to release the wedge from the adaptor or tooth base, or the nose portion of the excavator bucket. 30 3. A wedging device according to claim 2 wherein the restraining means is in the form of stop means which is located on the rotatable member and abuts the wall of the spool when the threaded member is rotated in an opposite second direction to thereby restrain movement of the threaded member away from the wedge.
4. A wedging device according to any one of the preceding claims, wherein the device is adapted such that IA the wedge is able to exert a force on the adaptor or 92 40V* tooth base. 31109 in a direction which is substantially perpendicular to a longitudinal axis of the wedging device, when the wedging device is located between the adaptor or tooth base and said nose portion and when the rotatable member is rotated in the first direction. A wedging device according to any one of the preceding claims wherein the rotatable member is received by a receiving portion of the wedge that protrudes into a channel defined in the spool and wherein the wedge is guided along the spool when the rotatable member is rotated in the first direction by the reception of the receiving portion in the channel.
6. A wedging device according to any one of the preceding claims, wherein the spool has a wall through which the rotatable member extends, and wherein the wall :."restrains the rotatable member from moving along the device when rotated in the first direction.
7. A wedging device according to claim 5, wherein the •spool has a wall for restraining iovement of the rotatable member toward the wedge when the rotatable e member is rotated in the first direction, and wherein the S 25 wall defines an end of the channel and the rotatable member extends into the channel through an aperture formed in the wall. 0 *000 r
8. A wedging device according to any one of the preceding claims, wherein the wedge is in contact with an inclined surface of the spool and is moved along the inclined surface when the rotatable member is rotated.
9. A wedging device according to claim 8, wherein the wedge is in face-to-face contact with the inclined surface of the spool. jLIA 31109 -11- A wedging device according to any one of the preceding claims 1 to 10, wherein the wedge is adapted to be pressed into face-to-face contact with the adaptor or tooth base.
11. A wedging device according to any one of the preceding claims, wherein the rotatable member is a bolt having a thread which engages with a thread on the wedge.
12. A kit for a wedging device as defined in any one of the preceding claims, comprising the spool, the wedge and the rotatable member.
13. An assembly comprising the wedging device and the adaptor or tooth base and said nose portion as defined in any one of the preceding claims, wherein the adaptor or tooth base and said nose portion have openings which align to form a passageway and the wedging device is arranged in the passageway such that the wedge is pressed g 20 against the adaptor or tooth base and the spool is in contact with the nose portion of the excavator bucket. o o
14. A wedging device substantially as hereinbefore described with reference to any one of figures 1, 3 and A kit for a wedging device substantially as hereinbefore described with reference to any one of Figures 1, 3 and 4.
16. An assembly substantially as hereinbefore described with reference to Figure 4. Dated this 22 nd Day of December 1999 THE ANI CORPORATION LTD By their Patent Attorneys GRIFFITH HACK 31109