GB2134160A - Earth drill - Google Patents

Abstract

The present invention provides a support 10 for the motor 7 and rotary table 6 of a crane mounted earth drill which support 10 comprises a member adapted to be mounted pivotally at the foot of the jib 3 of the crane and to support the drill table 6 and its drive motor 7 the member having an open face towards the jib 3 of the crane when in position whereby the jib 3 of the crane can be lowered into the member 10 for transport. In a particularly preferred form of the invention, the support member is formed as a collapsible structure (not shown) whose geometry can be readily altered whilst in position on the crane, thus making it possible to achieve simple fore and aft movement of the drill table as well as aligning the axis of the table 6 and the kelly 4. <IMAGE>

Description

SPECIFICATION Earth drill The present invention relates to an improved earth drill.

In crane mounted earth drills, the drill table and the motor driving it are mounted on a support at the base of the jib of the crane with the drill tubes or kelly being suspended from the top of the jib of the crane. However, this system is cumbersome in operation, since it is time consuming to assemble and dismount the table, motor and support every time that the crane is to be moved to a new site.

Problems are also encountered in aligning the tip of the drill accurately with the hole being dug.

Whilst angular orientation can be achieved with comparative ease, fore and aft alignment is not easy due to the difficulty in manoeuvring a crawler unit with accuracy over small distances. Also, it is necessary to to align the tip of the jib with the table centre and the axis of the drill tubes so as to avoid stressing of the drill tubes and the kelly due to the drive being out of alignment.

We have now devised a form of support member which reduces some or all of these problems. Hitherto, the support members have had a solid face towards the crane jib. In the present invention the face of the support facing the jib is formed as an open face so that the jib can be lowered into the support member sufficiently to permit the crane to be transported on a lower loader without having to remove the support member from the crane. This saves valuable time in moving from site to site and makes it commercially feasible to use a crane mounted earth drill for sites where they would hitherto have been uneconomic. The use of a crane mounted drill offers advantages over truck mounted drilling rigs (which otherwise offer the advantage of being readily transported units) in that truck mounted rigs often get bogged down whereas the crawler base of the crane does not.

Accordingly, the present invention provides a support for the motor and table of a crane.

mounted earth drill which support comprises a member adapted to be mounted pivotally at the foot of the jib of the crane and to support the drill table and its drive motor characterised in that the member has an open face towards the jib of the crane when in position whereby the jib of the crane can be lowered into the member for transport.

In particularly preferred form of the invention, the support member is formed as a collapsible structure whose geometry can be readily altered whilst in position on the crane, thus making it possible to achieve simple fore and aft movement of the drill table as well as aligning the axis of the table and the kelly.

The invention can be applied to a wide range of designs and types of crane. For convenience, the invention will be described hereinafter in terms of two preferred forms thereof as shown in the accompanying drawings in which: Figure 1 is a diagrammatic side view of a rigid form of the support of the invention; Figure 2 is a vertical section through the support of Figure 1; Figure 3 is a diagrammatic side view of a collapsible version of the support of the invention; and Figure 4 is a plan view of part of the support of Figure 3.

A conventional crane 1 is mounted on a crawler base 2 and has a jib 3 extending upward and forward in the conventional way. Suspended from the top of the jib 3 in the usual manner is a kelly 4 of conventional design and construction. The kelly extends downward through a drill table 6 driven by a motor 7, again both of conventional design and construction. The drill tube carries at its basal end a drill auger (not shown).

The drill table 6 and the motor 7 are mounted upon a support member 10, which carries the weight of the table and motor and serves to align the kelly and table so that they rotate about a substantially common axis. The support member 10 is mounted, by a pivotal mounting at or adajacent the foot of the jib 3 of the crane, e.g. by means of a socket in member 10 or an arm 11 which is journalled on the same cross shaft 8 which carries the jib foot. Preferably, arm 11 is mounted on lugs carried by the crane body adjacent the foot of the jib as shown, the shaft 8 by means of a hook arrangement as shown, so that the support can be readily separated from the crane.

Preferably, the member 10 comprises two side members 12, each carrying an arm 11 and linked by one or more transverse members 13, so as to form a generally U shaped structure with the open face of the U directed towards the jib of the crane.

Whilst the side members 12 can be of any suitable shape, we prefer that they are of a triangular shape with the hypotenuse running from the foot of the jib to the front outer edge of the drill table when in use, the member 13 linking the side members 12 along the hypotenuse. If desired, the side members can be inclined inwardly or can be cranked to taper the member 10 away from the jib 3, thus improving the view of the drill tip from the cran driver's operating position. The dimensions of the member 10 can be essentially the same as for a conventional support.

As indicated above, the jib is to be lowered into the open side of the support member 10 for transport. This requires that the open face of member 10 be sufficiently wide to receive the jib of the crane on which it is mounted.

If desired, the upper corners of member 10 and the open face can be mounted to the body of the crane by means of one or more hydraulic rams 20 which can be used to raise or lower the member 10 about its pivot point at or adjacent the base of the jib. The rams 20 or the upper corners of the members 10 can be mounted onto the crane body by means of a series of struts and cross-members 21 bolted or otherwise fixed to the body of the crane was with a conventional mounting member.

The member 10 can be constructed using slab steel and conventional methods as for a conventional support member; or can be made by modifying an existing member but cutting away the rear face of the member to give an open rear face and to expose the interior of the member for the jib to nest into. Alternatively, the member 10 can be formed as an open framework made from rods, bars or strips of steel, which will further improve the driver's view of the drilling operation.

The motor and drill table are mounted on member 10 in the conventional manner, e.g. by means of pins or bolts engaging lugs 30 at the top corners of member 10. By suitable selection of the dimensions of member 10, it can be made to suit a wide range of different cranes with differing lifting loads.

The above form of member 10 enables an operator to lower the jib into the open face of member 10 until it rests against the rear wall of the member or other suitable stops within member 1 0. If necessary, member 10 can pivotted about its mount at the foot of the jib, so that the member lies substantially parallel to the jib as it is lowered. By lowering the jib into the member 10, the jib can be lowered sufficiently to be loaded onto a low loader without the need to remove the member 10.

In a preferred form of the member 10, the geometry can be varied so that the member can be used to achieve fore and aft adjustment of the position of the drill tip without the need to move the crane on its crawler tracks. This makes it possible to achieve accurate positioning of the drill tip rapidly and simply. Also, the variable geometry can be used to align the table and kelly so that they all rotate about a substantially common axis.

The variable geometry is conveniently achieved by forming the support member 10 as two separate sets of bearers, either of both of the sets incorporating means for extending or contracting the bearer. One set of bearers supports the front edge of the motor/drilling table platform 40, the other set supports the rear edge of the platform.

The bearers can take a number of forms, e.g. they can be two T shaped beams linked at the upright of the T by a screw member or via a sliding fit of one beam within or over the other; or they can be in the form of an X shaped frame with each leg of the X being of variable length. If desired, the support can be formed from four separate legs of variable length each supporting a corner of the platform 40. A particularly preferred form of variable geometry member 10 comprises two cross beams carrying lugs or the like to engage the platform 40 or to carry beams supporting the motor and table. The cross beams are each carried at the ends of a beam 43 or 44. Either or both of beams 43 and 44 are formed so that their length is adjustable, the extension preferably being achieved by means of an hydraulic ram 41 on each beam.

Beam 43 is mounted at or adajcent the foot of the jib of the crane, e.g. by carrying at its foot a transverse bearing tube or beam 46 which pivots about a point adajcent the foot of the jib. This engagement can be achieved by journalling the beam 46 on the pivot pin of the jib, or by means of lugs or hooks 47 extending from the crane body to engage with a pivot pin on beam 46. Similarly, the foot of beam 44 is mounted at or adjacent the foot of the jib to extend upwardly and generally parallel to the jib to support the rear of the motor/table platform 40. The foot of beam 44 can be mounted on the pivot pin 8 of the jib as for beam 43.

However, it is preferred to mount the foot of beam 44 on beam 43, e.g. by means of lugs or other bearers 45 on beam 43 adjacent its foot. The head of beam 44 is mounted on a framework carried by the body of the crane at approximately roof level of the crane. The framework on the crane body can be of conventional form for supporting the upper corner of a rigid motor/table support member. Preferably, the head of beam 44 is mounted on a pivot pin or cross-bar 48 whose position fore and aft with respect to the crane can be altered by means of one or more hydraulic rams 50. Conveniently, the rams are incorporated in side members of the framework 49 on the crane.

In this way the position of the rear edge of platform 40 can be varied both fore and aft and vertically.

The ability to alter the lengths of the front and/or rear beams supporting the platform 40 gives the operator the ability to alter the angle at which the platform 40 lies and hence to align the drill table and the kelly on a common axis. By altering the fore and aft position of the head of the rear beam 44 and varying the legnth of beams 43 and 44 an operator of the crane can move the tip of the drill forwards or backwards over the ground without having to move the crane.

The feet of beams 43 and 44 are preferably demountable from the crane, so that the beams can be demounted when it is desired to collapse the member 10 formed from the beams so that the jib can be lowered for transport. If desired, further hydraulic rams can be provided to assist erection and lowering of beams 43 and 44 forming the member 10. In this eay, member 10 can be made so that it is fully collapsible for transport, yet can readily be remounted and extended for use after transport. Transport can be achieved on a single low loader as compared with the two which are usually required with a conventional rigid support frame into which the jib can not be lowered.

Claims (10)

1. A support assembly for the drill motor and table of a crane mounted earth drill which assembly comprises a member 10 adapted to be mounted pivotally at the foot of the jib 3 of the crane and to support the drill table 6 and its drive motor 7 characterised in that the member 10 has an open face directed towards the jib 3 of the crane when in position whereby the jib 3 of the crane can be lowered into the member 10 for transport.

2. A support assembly as claimed in claim 1 wherein the member 10 is formed as a collapsible structure 40, 41,43, 44, 45, 46, 47 whose geometry can be readily altered whilst in position on the crane whereby fore and aft movement of the drill table and alignment of the axis of the table and the kelly of the drill suspended from the jib of the crane can be achieved.

3. A support assembly as claimed in claim 1 wherein the member 10 comprises two side members 12 each carrying means 11 for mounting the member 10 at or adajcent the foot of the jib 3 of the crane and linked by one or more transverse members 1 3 so as to form a generally U shaped structure with the open face of the U directed towards the jib 3 of the crane.

4. A support structure as claimed in claim 3 wherein the side members 12 are of a triangular shape with their hypotenuse running from the foot of the jib to the front outer edge of the drill table 6 when in position, the member 13 linking the side members 12 along the hypotenuse.

5. A support assembly as claimed in either of claims 3 or 4 wherein the side members 12 are inclined or cranked inwardly to taper the cross section of the interior of the assembly 10.

6. A support assembly as claimed in claim 2 wherein the collapsible structure comprises two bearers 43, 44, at least one of which is axially extensible, each bearer being adapted to be pivotably mounted at or adajcent the foot of the jib 3 of the crane and to extend upwardly and forward of the crane, the free end one bearer being adapted to support the front edge of a drill motor and drill table platform 40, the free end of the other bearer being adapted to support the rear edge of the platform 40; and axially extensible means 49, 50 adapted to be connected to the crane and adapted by axial extension or contraction thereof optionally in co-operation with axial extension and/ór contraction of bearers 43 and/or 44 to move the platform 40 fore and aft relative to the crane.

7. A support assembly as claimed in claim 6 wherein the bearer 43 adapted to support the front edge of the platform 40 carries pivotably mounted thereon the lower end of the second bearer 44 adapted to support the rear edge of platform 40, the first bearer is itself adapted to be pivotably mounted by its lower end at or adjacent the foot of the jib 3 of the crane; there being provided at or adjacent the free end of the second bearer 44 or in co-operation therewith an axially extensible member 49, 50 adapted to be connected to the crane for fore and aft movement of the platform 40.

8. A support assembly according to claim 1 substantially as hereinbefore described with respect to either of Figures 1 and 2 of the accompanying drawings.

9. A support assembly according to claim 2 substantially as hereinbefore described with respect to either of Figures 3 and 4 of the accompanying drawings.

10. A crane mounted earth drill provided with a support assembly for the drill table and drill motor thereof as claimed in any of the preceeding claims.