JPH0359229A - Exchange point of excavation blade - Google Patents

Abstract

PURPOSE: To reduce wear and fatigue of a nose, to reduce loosening of a point fitting and to lengthen the life of the nose by providing a long supporting surface and a pair of lugs with space in a vertical direction on the point. CONSTITUTION: At a front tip part of a comparatively thin and long integral main body, a ground engaging edge part is provided and an adapter nose receiving socket formed by a top, a bottom part and a pair of side walls is provided. Next, at least one of the side walls is extended backward beyond the top and a bottom wall, and upper and lower ear projecting parts which are aligned so as to receive a lock pin C" and are away in a vertical direction are provided near top parts and bottom parts of the side walls. As a result, supporting pressure of a point in a nose B" is reduced, and wear and fatigue of the nose B" can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION This invention relates to drilling teeth, and in particular to certain novel points which are an improvement of U.S. Pat. No. 4,761,900 and an improvement of U.S. Pat. No. 4,353,532. .

Prior Art U.S. Pat. No. 4,761,900 discloses a method for use with teeth under the trade name HEL I LOK, which is sold worldwide as seen in U.S. Pat. No. 4,353,532. A novel locking device is provided to replace the U-shaped fitting. U.S. Patent No. 4.761.90
No. 0 uses a driven through pin that is maintained in place by a plug member or keeper that extends transversely, or horizontally, of the length of the adapter so as not to be distorted by impact loads. The vertical locking pin of U.S. Pat. No. 4,761,900 is held in place by ears on the rear of the point that cooperate with a pair of vertically spaced lugs on the adapter. These projections, which cooperate to retain the bottle, have rearwardly generally arcuate or rearwardly facing convex sides.

Problem to be Solved by the Invention The inventors have discovered that a substantial improvement in operation can be achieved by using a pair of vertically spaced lobes in the point lobes, regardless of the degree of curvature of the bottle. I found it.

By using spaced ears on the points, a point and nose assembly shape has been created that provides an improved operating life of the nose. In the discussion, the end of the operating life of a drilling gear nose is most commonly determined by one or the other of two types of defects:

1. The disadvantage of the point-holding nose is caused by the wear of the nose during operation to fit the point into the nose so loosely that the point falls off or breaks.

2. Structural defects in the nose under fatigue conditions. The improved nose operating life provided by the points and nose structure of this invention is due to the reduction in both types of defect sources.

Means for Solving the Problems With respect to nose wear, the configuration of the present invention reduces the support pressure on the points at the nose by providing a long support surface, thereby reducing the rate of nose wear and the consequent loosening of the point fit. reduce

Also, a "swing" type support of the point support lock pin to the nose is provided to reduce wear on the lock pin support surface at the nose. U.S. Pat. No. 4,761,900 discloses that the spaced lobes of the bount of this invention rub against the nose ears through a small up-and-down movement induced by the point under load. , allowing a lock pin shape that can absorb point-induced actuation through rocking. This rocking equalizes the wear of the nose lock pin support surface at a slower rate compared to the configuration of U.S. Pat. No. 4,761,900 as with a sliding block for a single similar rolling car. Additionally, the configuration of the present invention ensures that the rear side wall of the point completely protects the nose bin support surface and the bin itself from all external wear, i.e., abrasive dirt and wear from the rock the teeth are digging. Although it is clear that a tight fit is required to keep the points in place on the adapter, the adapter nose (U.S. Pat. No. 2.919, No. 506, No. 3.079.710).The basic liplock tooth arrangement of U.S. Pat. It is capable of supporting and retaining the point on the nose after it has developed from wear, which is superior to other tooth devices in this regard, such as in the tooth device of U.S. Pat. However, beyond the inability of a given tooth device to support and retain the points, there is a limit to loosening that varies conversely with the intensity of use. There is an extension of the actuation amount before it is achieved.

Functional Regarding nose fatigue defects, the use of spaced apart ears at points allows for the elimination of protruding ears in the nose. Such protruding ears cause stress concentration. Therefore, such removal creates a large nose fatigue stress and allows a long bearing surface, two advantages which more than compensate for the slight loss of material in the nose as would provide a new side locking pin recess.

The main advantages are the achievement of a previously unattainable tight fit in the adapter, the elimination of stress concentrations at the joint of the adapter handle and nose, and the achievement of large points for nose support length.

Points with vertically spaced, rearwardly extending ears have already been used, as in US Pat. No. 4,326,348, where the ear action provided stability in cooperation with the roof of the ear.

The prior art does not teach the preferred operation of spaced apart rearwardly extending ears to restrict the locking pin to its original locked position.

The invention will be explained with reference to the accompanying drawings.

Embodiment Referring to FIG. 1, there is shown the tooth hem lock "HELILOK" (trade name) of US Pat. No. 4,353,532. This tooth is secured by a point A, an adapter with a nose B, and a U-shaped lock C.

This tooth structure is particularly suitable for forming a strong nose because there is no locking pin opening.

However, this tooth presents difficulties encountered in removing the U-shaped lock C, which was overcome by the use of the driven piercing pin C of U.S. Pat. No. 4,761,900, as shown in FIG. A particularly preferred feature of the design of U.S. Pat. No. 4,761,900 was the use of an untensioned keeper or lateral plug D. The tooth points in FIG. 2 are labeled A because they are the same as the tooth points in FIG. However,
The adapter nose of FIG. 2 is modified from the adapter nose of FIG. 1 and is therefore designated B'. As indicated above, the lock has been modified so that the drive through bin of FIG. 2 is labeled C'.

According to the invention, the points, adapter noses and pin locks are all modified and labeled A'B'', C'', but the keeper remains unchanged and is therefore labeled.

The invention is based on the discovery that the bin moves with the point when the point is under an impact load. This is clear from the schematic diagram shown in FIG. In FIG. 7, the adapter nose is shown as a solid line and is labeled 20.
is attached.

The locking pin is also shown in solid line and is labeled 21 in the non-impact condition.
is attached. However, the tooth point is shown in dotted lines and labeled 22 and is in a non-impacted, resting state.

A downwardly directed impact load or stress as shown schematically by dotted line 23 is applied to point 2 in the shape shown by dotted line 22''.
2 comes to pivot on the adapter nose 20. The locking pin 21 similarly pivots to the position indicated by the dotted line 21'', which indicates the rocking or rolling action shown above;
As shown in FIG. 5, there is an advantage that the surface 24 of the nose recess that engages with the intermediate portion of the lock pin 21 is not worn away.

Several modifications of the locking mechanism were made to find the advantage of the bin moving with the point of the drilling rig under configuration, one of the important being the locking pin support surface spaced apart on the point. It is to establish.

Lotubbin Points First, as will be apparent from a consideration of FIG. 3, in the illustrated embodiment the side wall of point A' extends rearwardly beyond socket 27 to provide ears 25,26. At the rear ends of these ears 25.26 there are integral projections 28.29 for the ears 25 and projections 30.31 for the ears 26.
is provided. The protrusion 29 is shown in the lower part of FIG. 4, and the protrusion 31 is shown in the upper part of the same figure. All of these protrusions 28, 29, 3o, 31 are shown in FIG. These protrusions 28.29.30.3
1 protrudes inward and extends perpendicularly to the longitudinal direction of the socket 27, that is, perpendicularly to the inside of the tooth.

From FIG. 6, the top 33 of the upper projection 31 and the lower projection 3
The vertical distance between the bottom 32 of the socket 27 having a circular cross-section at the rear end, i.e. the "nose cone" plane E in FIGS. 1-3, is the length of the rear diameter. That is understood.

This relationship has the advantage of structural strength and allows for an integral protrusion of appropriate length from the upright point of the support surface.

In the explanation, protrusions 30, 31 (as shown in FIG. 6) are used.
The inner surface 34.35 of the projection 28.29) is a partially sloped surface provided for minimum clearance around the nose cone surface E of FIG.

This is clearly shown in FIG. 6, where plane E° is the extension of the nose cone rearward to the portion of FIG. In the twisting assembly and disassembly of the points to the nose, the inwardly inclined surfaces of these protrusions 3o, 31 must define the nose cone and the extension surfaces E, E'. The combination of the flat high point ears of Figures 3-7 and the circular socket/nose cone cross section provides a suitably sized point ear protrusion outside this inner boundary cavity.

In this invention, the inner inclined surface of the ear protrusion, that is, the inner surface 3
4.35 is exactly circular, but sufficient action can be achieved with a straight bevel.

Referring to FIG. 5, in the recommended construction, a pair of forward facing protruding walls 36,37 are arranged in an arc of tight engagement with a longitudinally spaced portion of the recessed rear edge 38 of the locking pin 21. It is part of the surface. Only one pair of protrusions engages the locking pin in a given assembly, the other set of protrusions serving the purpose of permitting attachment of points rotated 180 DEG. This embodiment of rotating the point when it is about half worn away is sometimes practiced when very sharp cutting profiles are required.

Before assembly, the curvature of the concave rear edge 38 of the locking pin 21 corresponds to the set of arcuate surfaces of the protrusion wall 36.37 or the protrusion 28.29.
is smaller than the curvature of the corresponding set of .

Therefore, if the locking pin 21 is not assembled on the nose but is placed in contact with the arcuate surface of the protrusion wall 36,37, then near the ends of the protrusion surface, such as at the bottom 32, top 33. Make partial contact. By assembling the locking pin to the point and nose assembly, this contact of the locking pin on the arcuate surface of the protrusion results in a forward convex shape with the front wall 24 of the nose recess 40 as shown in FIG. 5.8.10. Through the contact of the edges 39, the pins are made to flex and are thus spread out further. Finally, under the operating load experienced at the point during operation,
Because the pin is more flexible, the curvature of the concave trailing edge 38 substantially matches the curvature of the arcuate surface of the protrusion wall 36, 37 for full contact.

Of course, it is the flexibility of the pin that creates strong assembly forces.

Driving the pin into the point/nose assembly is facilitated by a sloped cut-off in the forward facing protrusion wall 36 as at 41 in FIG. When the entry end of the lock pin 21 passes over this slope 41, the lock pin 21 is deformed or curved in order to arrive at the forward facing protrusion wall 36.

Instead of using the ears 42 of FIG. 2 for support on the new locking pin C'°, the present invention uses a surface of the front wall of the nose recess 40 as shown in FIG. 4.5. 24 is used. The nose support surface is marked 2 in FIG.
It is either flat as shown at 4 or slightly arcuate as shown at 124 in FIG. Nominally, the locking pin is located near the longitudinal midplane of the nose at face 24.1 of the nose.
24, but the support moves above and below the intermediate plane during impact stress.

The nose recess 40 is formed by an integral edge 43 as far as the rear wall is concerned (compare FIG. 3.4). As is clear from the fact that this protrusion 43 is designated by the reference numeral 44.45 in FIG. 3.8 and by the reference numeral 144.145 in FIG. made up of together. The arc of the front wall surface 124 in FIG. 9 is tangential to the keeper opening 146 at the midpoint compared to the relationship of the front wall surface 24 to the keeper opening 46 in FIG. it is obvious. The face 24 of the front wall has a recess 47 to accommodate the insertion of a keeper (see FIG. 10).

Further, the protrusion 43 or 143 acts as a guide when attaching the lock pin. In this connection it was chosen to use the single-ear point construction of FIG. 11 in conjunction with the nose of FIG. 9, the teeth being used primarily for dredging and irreversible. The structure of the projections 28, 29 is the same as that in FIG. 3, but the ears forming the projections 30, 31 are omitted.

As shown in Figure 2.3, the lock pin C'' used in the point of this invention is curved forward, that is, it is normally curved. Bin C'
It is different from This facilitates the necessary rocking motion to minimize nose wear on the face 24 portion of the front wall.

Another configuration of locking pin 221 is shown in FIG. The ear part of the point in this configuration is the socket 27 of the point.
, but the forward facing tongue walls 236.237 are not arcs, and these tongue walls 236.
237 is flat and parallel for use with sandwich style locking pins. This sandwich type locking pin uses steel plates 248, 250 and layers forming a rubber core 249, as has been used industrially for many years. Although this configuration does not provide a suitable rocking engagement with the face 224 of the front wall of the noselock recess, it is suitable for light duty and has the advantage of plug D-less application. Retention of the locking pin in the assembly is provided by the engagement of the inner protrusion walls 236,237 of the protrusions 228,229 with the rear protrusion 251 of the rear layer of steel plate 248.

It will be clear that here corresponding protrusions are normally provided on either side of the point, as in corresponding recesses in the nose.

In the foregoing description, the detailed description of the invention is for illustrative purposes only, and many changes in the description set forth in section 2) can be made by those skilled in the art without departing from the spirit and scope of the invention.

Claims (10)

[Claims] (1) a relatively elongate unitary body having a ground engaging edge at a forward end and having an adapter nose receiving socket at the top formed by a top portion, a bottom portion, and a pair of side walls; At the excavation tooth replacement point extending rearwardly beyond the top and bottom walls, the rearwardly extending sidewalls have vertically spaced upper and lower ear projections near the top and bottom aligned to receive the locking pins. A drilling tooth replacement point characterized by: 2. A drilling tooth replacement point according to claim 1, wherein each ear extends inwardly from the side wall at substantially right angles to the socket for support with respect to the locking pin. 3. The drilling tooth replacement point of claim 2, wherein the socket has a substantially circular cross-section at the rear, and the top of the upper projection and the bottom of the lower projection are separated by approximately the diameter length of the circular cross-section. 4. The drilling tooth replacement point of claim 2, wherein each projection has an inwardly facing wall adjacent to one another that is partially sloped to conform to the shape of the socket. (5) Each protrusion has a wall facing forward, and a portion of the front wall of the lower protrusion adjacent to the upper protrusion is sloped rearward to guide the lock pin during installation. Excavation tooth replacement point described in item 4. 6. The digging tooth replacement point of claim 1, wherein the side walls extend beyond the top and bottom walls and each side wall is provided with a protrusion. 7. The excavation tooth replacement point according to claim 1, wherein each protrusion has a forwardly facing wall, the wall having an arcuate shape. 8. The digging tooth replacement point of claim 1, wherein each projection has a forwardly facing wall, said wall being flat. (9) combined with a nose mounting adapter provided with a vertically extending recess for receiving the locking pin, the groove having a front wall in supporting engagement with the middle portion of the locking pin, and the point ear protrusion locking; 2. A drilling tooth replacement point as claimed in claim 1 in supporting engagement with a locking pin adjacent the end of the pin. 10. A drilling tooth arrangement according to claim 9, wherein the adapter is provided with a horizontally extending recess coincident with the locking pin, having a resilient keeper of the locking pin within the groove, the groove extending inwardly from the recess. exchange points.