EP2288760B1

EP2288760B1 - Wear member connection device for a digging bucket

Info

Publication number: EP2288760B1
Application number: EP09731426A
Authority: EP
Inventors: Tor Torgrimsen
Original assignee: Komatsu KVX LLC
Current assignee: Komatsu KVX LLC
Priority date: 2008-04-10
Filing date: 2009-04-02
Publication date: 2013-04-03
Anticipated expiration: 2029-04-02
Also published as: NO334868B1; WO2009126045A1; EP2288760A1; NO20081744L

Description

A wear member connector is provided. It is, more particularly, a wear member connector in which a wear member is connected to an adapter by means of a pin and pocket connection, in which the pin of the adapter is in the pocket of the wear member.
A wear member, for example in the form of a replaceable tooth cap on a digging bucket, is often connected to the digging bucket by means of an adapter which is secured to the front piece of the digging bucket.
According to the prior art, the adapter is generally formed with a pin which fits complementarily into a pocket in the tooth cap. The tooth cap is often moulded and fitted by hand on the adapter, on which it is typically held in place by means of a locking pin or similar.
US-dokument 2006/0265916 describes a wear assembly that includes an adapter with a nose, a wear member with a socket to receive the nose, and a lock to secure the wear member to the adapter. The nose and socket include complementary rails and grooves that vertically diverge as they extend from the front of the nose. The lock can have a tapered construction. This document forms the basis for the preamble of the independent claim.
US-document 3371437 concerns a locking device in the form of a bolt with a half round head for securing a removable digger tooth point to a support shrank. The bolt is disposed in the shrank with the head interiorly of the assembled tooth point and shrank with the head rotatable from nesting engagement in a registering socket in the the tooth point and the point and shrank are secured together by the bolt after moving the socket out of register.
US document 5909962 describes a tip assembly for an edge of an implement of a work machine that includes an adapter secured to the edge of the implement. The adapter has an adapter aperture extending therethrough. The tip assembly also includes an implement tip having a tip aperture extending therethrough, the implement tip is positioned relative to the adapter such that the adapter aperture and the tip aperture align to form a passageway. The tip assembly further includes a sleeve subassembly positioned within the passageway. The sleeve subassembly includes (i) a first member, (ii) an intermediate member, and (iii) a second member. In addition, the tip assembly includes a fastener mechanically coupled to the sleeve subassembly wherein rotation of the fastener causes (i) the intermediate member to move in a first direction, and (ii) the first and second members to move in a second direction so as to tightly secure the sleeve subassembly within the adapter aperture.
The wear on the tooth cap is less unfavourable than wear on the adapter because the tooth cap can easily be replaced. Wear on the adapter, however, may lead to too poor a fit against the tooth cap or to breakage and need for replacement the adapter. The replacing of a welded adapter may constitute half a day's work.
The invention has for its object to remedy or reduce at least one of the drawbacks of the prior art.
The object is achieved through features which are specified in the description below and in the claims that follow.
A wear member connector is provided, in which a wear member is connected to an adapter by means of a pin and pocket connection, the pin of the adapter being in the pocket of the wear member, and the wear member being characterized by the pin abutting against the pocket at a first abutment portion, a second abutment portion and a third abutment portion.
By an adapter is meant, in this connection, any component which may be used to hold a wear member.
When the pin is placed in the pocket, the second abutment portion is on the opposite side of the pin between the first abutment portion and the third abutment portion. Similarly, the second abutment portion is located axially between the first abutment portion and the third abutment portion relative to the direction of insertion of the pin into the pocket. Thereby, the pin rests steadily against the pocket.
A preferred embodiment of the wear member connector is that the abutment portions are at different depths in the pocket, alternatively at different distances from the end portion of the pin.
A preferred embodiment of the wear member connector is that at least one of the abutment portions is placed transversely to the direction of insertion of the pin into the pocket.
Yet another preferred embodiment of the wear member connector is that at least one of the abutment portions extends over more than one side of the pocket or pin. If the pin and pocket connection has a circular cross section, an abutment portion may extend along an arc of the circumference. If the pin and pocket connection is given a cornered, for example square, cross section, the abutment portion may extend over more than one side.
Yet another preferred embodiment of the wear member connector is that at least one of the abutment portions is divided. An abutment portion may be divided by, for example, openings, recesses or hollow keys, or it may be divided for reasons of production.
Yet another preferred embodiment of the wear member connector is that each abutment portion is formed by an elevation on the pin or in the pocket. For example, protrusions in the pocket may contribute to a practical design of the wear member connector.
The wear member connector provided makes the wear member rest against its attachment at three defined portions, which enables steady and safe attachment of the wear member. If, additionally, the connector is formed with a conicity, strains during work will contribute to driving the wear member connector even harder together, so that wear between the components is substantially prevented.
In what follows is described an example of a preferred embodiment which is visualized in the accompanying drawings, in which:

Figure 1: shows a plan view of a wear member which is connected to a front piece by means of an adapter;
Figure 2: shows a section 1-1 of figure 1;
Figure 3: shows a section IIa-IIa of figure 2;
Figure 4: shows a section IIb-IIb of figure 2;
Figure 5: shows a section IIc-IIc of figure 2; and
Figure 6: shows in perspective a wear member, viewed from its mounting side.

In the drawings the reference numeral 1 indicates a wear member in the form of a tooth cap which is connected to the pin 4 of an adapter 2. The adapter 2 is secured to the front piece 6 of a bucket, not shown.
The pin 4 is given a shape like a frustum of a pyramid and has its smallest cross section at its projecting end portion 8. The pin 4 is formed with a through cut-out 10 for a locking pin 12. A stop screw 14 is threaded into the end portion 8.
The wear member 1 is formed with a pocket 16 which fits complementarily over the pin 4. The wear member 1 is provided with through openings 18 which correspond to the cut-out 10 of the pin 4 in such a way that the locking pin 12, when in the openings 18 and cut-out 10, prevents the wear member 1 from being movable off the pin 4.
Near the bottom of the pocket 16 is arranged a first abutment portion 20 in the form of a protrusion which builds out somewhat from a first side 22 and a second side 24 inside the pocket 16, see figure 3. The first abutment portion 20 is arranged to abut against the pin 4, whereas a third side 26 and a fourth side 28 have a clearance to the pin 4 in the section IIa-IIa.
Nearly halfway into the pocket 16 is arranged a second abutment portion 30 in the form of a protrusion which builds out somewhat from the third side 26 and fourth side 28 of the pocket 16, see figure 4. The second abutment portion 30 is arranged to abut against the pin 4, whereas the first side 22 and the second side 24 have a clearance to the pin 4 in the section IIb-IIb.
Near the outer opening of the pocket 16 is arranged a third abutment portion 32 in the form of a protrusion which builds out somewhat from the first side 22 and the second side 24 inside the pocket 16, see figure 5. The third abutment portion 32 is arranged to bear against the pin 4, whereas the third side 26 and the fourth side 28 have a clearance to the pin 4 in the section IIc-IIc.
Thus, the pin 4 has abutments against the first side 22 and the second side 24 by the first abutment portion 20 and the third abutment portion 32, and against the third side 26 and the fourth side 28 by the second abutment portion 30. This preferred embodiment provides a very steady and defined contact between the wear member 1 and the adapter 2.
By means of discs 34, the stop screw 14 has been built out somewhat from the end portion 8 to prevent the wear member 1 from being moved too far in on the pin 4 during work, which might lead to radial overloading of the wear member 1.

Claims

A bucket wear unit comprising a wear member (1) and an adapter (2), wherein the adapter (2) is securable to a front piece (6) of the bucket, and the wear member (1) is connected to the adapter (2) by means of a pin (4) and pocket (16) connection, in which the pin (4) is an integral portion of the adapter (2) and the pocket (16) is an integral portion of the wear member (1), characterized in that, the pin (4) abuts against the pocket (16) at a first abutment portion (20), a second abutment portion (30) and a third abutment portion (32), the abutment portions (20, 30, 32) protruding from the pin (4) or from a pocket side (22, 24, 26, 28), the second abutment portion (30) being on the opposite side of the pin (4) relative to the first abutment portion (20) and the third abutment portion (32), wherein when the pin (4) is placed in the pocket (16), the second abutment portion (30) is positioned axially between the first abutment portion (20) and the third abutment portion (32) relative to the direction of insertion of the pin (4) into the pocket (16).
The device in accordance with claim 1, charac - terized in that the abutment portions (20, 30, 32) are at different depths in the pocket (16).
The device in accordance with claim 1, characterized in that the abutment portions are placed at different distances from the end portion (8) of the pin (4).
The device in accordance with claim 1, characterized in that at least one of the abutment portions (20, 30, 32) are positioned transversely to the direction of insertion of the pin (4) into the pocket (16).
The device in accordance with claim 1, characterized in that at least one of the abutment portions (20, 30, 32) extends over more than one side (22, 24, 26, 28) of the pocket (16) or pin (4).
The device in accordance with claim 1, characterized in that at least one of the abutment portions (20, 30, 32) is divided.
The device in accordance with claim 1, characterized in that each abutment portion (20, 30, 32 is formed by an elevation on the pin (4) or in the pocket (16).