WO1988003200A1

WO1988003200A1 - Cleansing apparatus for excavators

Info

Publication number: WO1988003200A1
Application number: PCT/SE1987/000488
Authority: WO
Inventors: Gunnar Olsson
Original assignee: Gunnar Olsson
Priority date: 1986-10-22
Filing date: 1987-10-21
Publication date: 1988-05-05
Also published as: AU8156287A

Abstract

Apparatus for excavators of the type comprising a stick (2) and a bucket (1) carried by the stick. On the stick or the bucket, there is provided at least one cylindrical rotary brush (7) serving to remove a layer of material remaining after the removal of filling material over a conduit in order to expose this conduit.

Description

CLEANSING APPARATUS FOR EXCAVATORS

Technical field of the invention

This invention relates to a cleansing apparatus for excavators of the type comprising a pivotable arm and a bucket carried by the arm by means of a transverse hinge pin. In practice, the excavator may be a heavy digger or a tractor/loader which in con¬ ventional manner is equipped with a small-size exaca- vating bucket. State of the art For exposing conduits, such as electric cables or water pipes, buried in ditches, the filling mate¬ rial is first removed by means of the excavating bucket down to a level of about 20 cm above the conduit or to the protective strip normally placed above the conduit, whereupon the remaining material in the form of gravel and/or sand is removed manually with a shovel. Such manual removal of the filling material in the immediate vicinity of the conduits involves a number of drawbacks. Thus, the work is time-consuming and physically straining. Also, the risk of accidents is considerable, especially in the cases where the ditches holding the conduits are so deep that the earth on the sloping ditch sides may slide down into the ditch. Further, manual digging is costly inasmuch as the workers must wait, at least at times, for the excavator to perform its work, and vice versa. The fact that this procedure is time-consuming is espe¬ cially embarrassing when excavating conduit-holding ditches which cross e.g. roads carrying a lot of traf- fie, where it is of vital importance, especially for the commercial traffic, that the work be completed in as short a time as possible. Another common drawback is the risk of damage to the pipes or cables which arises when the workers, for reasons of convenience, try to have the operator of the excavator dig as deep as possible. It then often occurs that the bucket engages the pipes or cables so as to damage them. Brief account of the inventive concept The present invention aims at overcoming the above-related drawbacks by providing an apparatus by means of which the work of exposing buried con¬ duits is made much easier and much more efficient. According to the invention, this object is achieved in that at least one support arm is hingedly connected to the stick or the bucket and carries a substantial¬ ly cylindrical brush which is rotatable about a shaft substantially parallel to the hinge pin of the bucket and whic _r by pivotment^"of the support arm, is movable between a lowered position in which it is rotated for sweeping away a layer of material remaining after the removal of filling material over a buried ^"con¬ duit in order ;to expose the conduit, and a raised position in which the brush abuts against the stick. Further account of the state of the art

U.S. Patent Specification 3,922,475 discloses an auxiliary equipment in the form of a brush mounted on the side of a vehicle-borne loading bucket. The purpose of this brush is to permit cleansing surfaces located on elevated levels. To this end, the brush is of the type which has its axis of rotation at right angles to the surface to be swept clean and the indi¬ vidual bristles of which are arranged with their free ends in a common planar surface. The shaft of the brush can be mounted in a holder which is stationarily mounted on the outer side of a side member of the bucket. The bucket consists of a simple loading bucket whose open side faces away from the machine located behind and which, not only for this reason but also because the holder constantly projects from the side of the bucket, cannot be used for digging operations. Further, the brush cannot be used for cleansing and exposing conduits buried in the ground (there are often several juxtaposed conduits) because the soil or gravel would only be flung about in uncontrollable trajectories and the individual bristles would not be capable of working their way down to any considerable extent below the top face of the conduits. Brief description of the accompanying drawings

In the drawings, FIG 1 is a side view of the apparatus according to the invention shown in connection with the exposure of a buried conduit, FIG 2 is a front view as seen from the right in Fig. 1, FIG 3 is a side view of an alternative embodiment, and FIG 4 is a slightly modified perspective view of the embodiment according to Fig. 3. Detailed description of preferred embodiments of the invention

In the drawings, 1 designates a bucket which is carried in a per se known manner by an arm or so- called stick 2 and is pivotable relative to the stick by means of a hydraulic cylinder 3. More specifically, the bucket 1 is pivoted about a hinge pin 19 at the free end of the stick 2. Further, the stick 2 is articu- lated in a known manner to a second arm 4, in turn connected to a wheel-mounted or otherwise mobile machine (not shown), e.g. a tractor, an excavator or the like. In the drawings, a conduit (in the form of a pipe) is designated 5, while 6 designates a ditch excavated by the bucket 1. ^•

According to the invention, a rotary brush 7 is associated with the stick 2. More specifically, the brush 7 is mounted on a support arm, generally desig¬ nated 8, which is pivotally connected by a joint 9 to a holder 10 which is dismountably provided on the stick 2 in an optional manner. The pivotal movement of the support arm 8 is ensured by a first double- acting hydraulic cylinder 11 connected to the arm 8 by the intermediary of a link member 12 of the type capable of bringing about a substantial angular dis¬ placement when pivoting the arm. In the illustrated example, the support arm 8 can be swung more precisely from an active position adjacent the bucket 1 to a resting position indicated by dash-dot lines, in which the brush does not interfere with the regular working operations of the bucket 1. In the illustrated embodiment, the arm 8 is tele- scopically extensible by being composed of inner and outer tubes or hollow sections 8' and 8", respectively, which can be displaced relative to each other in the direction of _/the arrows by means of a second double- acting hydraulic cylinder 13. Thus, when the support arm has been swung down to its active position, the brush can be accurately positioned on the desired level relative to the bucket. Further, the telescopic design of the arm 8 allows the brush 7, when in its lowered active position, to be located at a relative¬ ly large distance from the joint 9 and, when in its raised inactive position, to be moved closer to the joint, so that the stick 2 can be pivoted unimpededly towards the second arm 4. The brush 7 has a substantially cylindrical shape with a width or axial extent which is slightly less than the width of the bucket 1, the individual bristles of the brush suitably consisting of highly resistant, relatively rigid, although elastically yielding fila- ments of steel, plastic or equivalent material. Op¬ tionally, the brush may include complementary elements, such as chain members, having a higher soil-working capacity than the thinner bristles. The brush 7 is mounted on a transverse shaft 14 (see Fig. 2) which is parallel to the hinge pin 19 and carried, on the one hand, by the support arm 8 and, on the other hand, by a fork arm 15 extending downwards from a cross- piece 16 projecting laterally from the support arm 8. The brush 7 is advantageously driven by a hydraulic motor 17 provided at the end of the support arm 8. This hydraulic motor can also be mounted within the shaft 14.

The brush 7 cooperates with a cover 18 extending in an arcuate fashion from the area in front of and below the centre axis of the brush to the area behind and above said centre axis, and at a certain distance from the circumference of the brush. In practice, the cover may consist of a rigid plate mounted on the support arm or its cross-piece 16. Optionally, the lowermost part of the cover may consist of an elastically yielding material, e.g. in the form of a rubber flap.

In an alternative preferred embodiment, shown in Figs. 3 and 4, the brush 7 is mounted on support arms 20 which are hingedly connected to the bucket and not to the stick 2. Suitably, the hinge pins 19' of the support arms 20 are coaxial with the hinge pin 19 for mounting the bucket on the stick 2, e.g. by being mounted in one or more additional brackets 21 fixed on the bucket on the same level as the regular mounting brackets which are provided on the bucket and which normally are part of the connection between the bucket and the stick. The two support arms 20 form a frame mounted in the two brackets 21 on each side of the stick 2. On the holder formed by the arms 20, there are provided one or more downwardly project- ing, suitably- arcuate support members 22 which can rest on the inner surface of the bucket in conjunction with the edges thereof. The stick 2 is provided with a locking device 23 for retaining the support arms when raised against the stick 2. This locking device may consist e.g. of a remote-controlled electromagnet, a mechanical quick coupling or a combination thereof. The brush 7 is easily pivoted from its lowered, active position to its raised, inactive position (indicated by dash-dot lines in Fig. 3) by pivoting the bucket upwards towards the stick. The supporting frame 20-20 is then entrained by the pivotal movement and can be locked to the stick 2 by means of the above-mentioned locking device 23. When the brush 7 should be pivoted to its active, lowered position, the locking device 23 is released, and the brush and the supporting frame will swing down by gravity to the active position of the brush. This downward pivotal movement can of course be effected in a controlled manner with the aid of the bucket 1.

In this alternative embodiment, there is no need of any additional, expensive hydraulic equipment in addition to the hydraulic motor 17 ' driving the ^"brush 7 since the pivotal movement is carried out entirely by means of the hudraulic equipment of the bucket 1. Since the pivot arms 20 are fixed in association with the bucket 1, their length can be kept at a mini- mum, whereby it is possible to avoid that the brush 7, when in its upwardly pivoted position, adversely affects the operation of the stick 2 when the machine is used for excavating. Thus, it ILS^" not necessary to make the support arms telescopic. In this way, a very simple and inexpensive cleansing apparatus is achieved. This apparatus may of course be equipped with a cover 18 and otherwise be given a. design ana¬ logous with that in Figs. 1 and 2. Operation and advantages of the inventive apparatus The operation of exposing the conduit 5 is commenced by excavating the ditch. This is carried out in a con¬ ventional fashion by means of the bucket 1, with the brush 7 held in its upwardly pivoted,^" inactive position indicated by dash-dot lines. This excavation can be carried out over an arbitrary distance, e.g. 5-10 m, and down to a level of about 20 cm above the conduit 5. In practice, coarse filling material, e.g. of the moraine type or the like, is removed while finer gravel which normally surrounds the conduits and may lie below a protective strip is not affected by the bucket. The excavator is thereafter reversed to its starting position, and the brush 7 is swung down to its active position indicated in full lines in Fig. 1. When the brush is thereafter rotated in the clock-wise direction in Fig. 1, the gravel will be swept away from the area around the conduit and flung, with the aid of the cover 18, in an arcuate trajectory around the brush and into the bucket 1 which, at this stage, is held immediately behind the brush in the manner illustrated in Fig. 1. In this way, the excavator is advanced along the conduit while the gravel is being swept away and continuously taken care of by the bucket by means of which the collected material can be placed in heaps and subsequently used -for back¬ filling the ditch. Thus> one and the same operator can perform not only the digging operation by means of the bucket but also the final delicate operational step consisting in freeing the conduits from the ma¬ terial surrounding them. In comparison with manual digging, the conduits can be exposed quickly and without any risk of damage either to the conduits themselves or to the personnel. Since the fine gravel or sand material can be efficiently collected in the bucket, it is also possible to use the material again when backfilling the ditch, which is of major importance in terms of economy. Possible modifications of the invention

It goes without saying that the invention is not restricted only to the embodiments described above and shown in the drawings. Thus, it is conceivable, for instance, to dispense with the illustrated cover and, instead of collecting the gravel directly in the bucket in connection with the brushing operation, to sweep the material in front of the apparatus and subsequently collect it in the bucket in one separate step. Also, it is conceivable, in the absence of a cover, to brush the material directly up into the bucket by reversing both the direction of rotation of the brush and the direction of travel of the ex¬ cavator. According to another conceivable embodiment, the support arm can be pivoted to its inactive position, not in the same plane as the excavator arms 2, 4, but in a direction at right angles to this plane, e.g. through 180 from its lowered position to a raised position. In this context, it should also be pointed out that, in actual practice, the inventive apparatus is advantageously easily dismountable from the excavator arm. However, it should be stressed that, in special cases, the apparatus may be stationarily mounted on the excavator arm, in which case the apparatus- is an additional equipment only in the sense that it supplements the excavator. Also, it is conceivable to dismount the bucket from the stick and connect a brush according to the invention to the stick. Final¬ ly, it should be pointed out that the apparatus now described can also be used on vehicles other than excavators and tractors, e.g. crane trucks with exca¬ vator equipment.

Claims

1. A cleansing apparatus for excavators of the type comprising a pivoted arm or stick (2) and a bucket (1) carried by. said arm via a transverse hinge pin (19), c h a r a c t e r i z e d in that at least one support arm (8, 20) is hingedly connected to the stick (2) or the bucket (1) and carries a substantially cylindrical brush (7) which is rotatable about a shaft (14) substan¬ tially parallel to the hinge pin (19) of the bucket and which, by pivotment of the support arm, is movable be- tween a lowered position in which it is rotated for sweeping away a layer of material remaining after the removal of filling material over a buried conduit (5) in order to expose the conduit, and a raised position in which the brush abuts against the stick. ^* ^*

2. Apparatus as claimed in claim 1, c h a r a c ¬ t e r i z e d in that the support arm (20) is hingedly connected to the bucket ( 1 ) with its hinge pin co¬ axial with the hinge pin (19) about which the bucket is pivotal relative to the stick (2).

3. Apparatus as claimed in claim 1, c h a r a c ¬ t e r i z e d in that the support arm (8), in addition to being pivotal, is telescopically extensible.

4. Apparatus as claimed in any one of the preced¬ ing claims, c h a r a c t e r i z e d in that the brush (7) is rotatable by means of a hydraulic motor (17) mounted on the support arm (8)^' and/or within an associated drive shaft (14).

5. Apparatus as claimed in any one of the preceding claims, c h a r a c t e r i z e d in that the rotary brush (7) is arranged to cooperate with a cover (18) serving to guide material which is swept by the brush in a direction away from the bucket, back into the bucket along a trajectory around and above the brush.