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FIELD OF THE INVENTION  
       [0001]     The present invention relates to a handling apparatus and especially but not exclusively to a handling apparatus for drill rods.  
       BACKGROUND  
       [0002]     There are a number of difficulties associated with powered equipment for handling drill rods, including lack of space at some mast locations, adequately accurately orientating the drill rods for insertion into a drill string or placement on a drill rod stand, and stable and secure handling of drill rods of considerable length and mass.  
         [0003]     It would be desirable if at least preferred embodiments of at least some aspects of the invention could mitigate one or more of these difficulties.  
       SUMMARY OF THE INVENTION  
       [0004]     According to a first aspect of the present invention there is provided a handling apparatus comprising:  
         [0005]     a base unit;  
         [0006]     a first elongate support pivotally coupled at a first end to the base unit;  
         [0007]     a second elongate support pivotally coupled at a first end to the base unit;  
         [0008]     a head assembly for releasably retaining an elongate member, said head assembly being supported, in use, by the first and second elongate supports;  
         [0009]     wherein the first and second elongate supports are pivotally coupled to the head assembly at respective second ends thereof; and  
         [0010]     whereby the first and second elongate supports can pivot relative to the base unit whilst remaining substantially mutually parallel with at least part of the head unit maintained in a substantially constant orientation.  
         [0011]     Preferably the first and second supports are substantially co-planar.  
         [0012]     Preferably the first and second supports are, in use, provided in a substantially vertical plane.  
         [0013]     Preferably there is provided a driving mechanism for forcing the first and second supports to pivot relative to the base unit.  
         [0014]     The driving mechanism may force one of the first and second supports, which in turn forces the other support.  
         [0015]     The head preferably includes a first head portion which is pivotally coupled to the second ends of the first and second supports.  
         [0016]     The head preferably includes a second head portion which is selectively orientable relative to the first head portion.  
         [0017]     Preferably there is provided a driving mechanism for orientating the second head portion relative to the first head portion.  
         [0018]     The second head portion preferably supports one or more clamping mechanisms for clamping onto an elongate member.  
         [0019]     Preferably the one or each clamping mechanism comprises a pair of jaws.  
         [0020]     Preferably the handling apparatus is for handling elongate members which are drill rods.  
         [0021]     Preferably the handling apparatus further comprises at least one pair of jaws for gripping an elongate member to be handled, said pair of jaws being operable between a more open configuration and a more closed configuration by a driven member moveable between a first position and a second position, wherein the relative motion of the jaws between the more open configuration and the more closed configuration is substantially in a plane, and the direction of movement of the driven member between the first and second positions is substantially perpendicular to said plane.  
         [0022]     According to a second aspect of the present invention there is provided a handling apparatus for handling elongate members comprising:  
         [0023]     a base unit;  
         [0024]     at least one support member extending from the base unit, the at least one support member being pivotally attached to the base unit at a first end of said at least one support member; and  
         [0025]     a head assembly comprising a retaining mechanism for releasably retaining elongate members;  
         [0026]     wherein the head assembly includes a first link for attachment between the at least one support member and the retaining mechanism, said first link being pivotably coupled with respect to the retaining mechanism and the at least one support member.  
         [0027]     Preferably the handling apparatus further comprising a second link between the first link and the retaining mechanism, said second link being pivotally coupled to the first link and the retaining mechanism.  
         [0028]     Provision of serial first and second links between the support member and the retaining mechanism helps provide a wide range of possible orientations for the retaining mechanism relative to the at least one support member facilitating capture of elongate members in a wide range of orientations.  
         [0029]     Preferably there are provided at least two support members, each pivotally coupled to the base unit.  
         [0030]     Preferably the at least two support members are pivotally coupled to the first link member.  
         [0031]     Preferably the at least two support members are arranged to remain substantially mutually parallel during use of the apparatus.  
         [0032]     A locking mechanism for preventing pivotal movement of the second link relative to the first link may be provided.  
         [0033]     The locking mechanism may comprise a locking member adapted to prevent relative movement of adjacent portions of the first and second links.  
         [0034]     The said adjacent portions of the first and second links are preferably spaced apart from the pivotable coupling of the first and second links.  
         [0035]     The said adjacent portions of the first and second links may define respective apertures.  
         [0036]     The locking member may be adapted to be retained in said apertures.  
         [0037]     The apparatus preferably further comprises a support driving mechanism for forcing relative pivotal movement of the at least one support and the base unit.  
         [0038]     The apparatus preferably further comprises a retaining-mechanism driving mechanism for forcing relative pivotal movement of the retaining mechanism relative to the support.  
         [0039]     The retaining-mechanism driving mechanism preferably comprises a first driving element for forcing relative pivotal movement of the second link relative to the first link, and a second driving element for forcing relative pivotal movement of the retaining mechanism relative to the second link.  
         [0040]     The driving mechanisms and/or driving elements preferably comprise hydraulic pistons. However, as an alternative, other driving mechanisms or elements could be used as one or more driving mechanisms and/or elements.  
         [0041]     The retaining mechanism preferably comprises an elongate frame.  
         [0042]     Preferably, in use, the elongate frame is adapted to be at a fixed angle relative to an elongate member being retained by the retaining mechanism.  
         [0043]     Preferably, in use, the elongate frame is adapted to be substantially parallel to an elongate member being retained by the retaining mechanism.  
         [0044]     In a preferred embodiment which includes first and second supports, adapted to remain substantially mutually parallel, the second link may be pivotally locked relative to the first link, and the orientation of the first link is maintained constant during pivoting of the support members due to the four-bar linkage formed by the base unit, support members and first link. This means that the orientation of the second link is constant even when the second link, and the retaining mechanism, are being moved laterally relative to the base unit. Thus, the orientation of the elongate frame of the retaining mechanism is determined by the relative orientation of the elongate frame and the second link. Thus one or more stops or limiters may be provided on the second link to define the extremes of the orientation of the elongate frame. This can be of considerable utility since in, for example, a situation where elongate members are to be picked up from a rack where they are to be provided by the apparatus at 30 degrees to the vertical, the steps or limiters can be set to define appropriate angles of the elongate frame. This helps eliminate operator error and greatly facilitates handling elongate members.  
         [0045]     In a preferred embodiment at least one pair of jaws is provided to grip elongate members.  
         [0046]     The jaws are preferably moveable parallel to the elongate frame. This allows proper positioning of elongate members in, for example, a preferred embodiment in which the height at which the elongate frame is positioned varies as the elongate frame is moved laterally towards or away from the base unit.  
         [0047]     Preferably the base unit is rotatable.  
         [0048]     Preferably the base unit is rotatable about a substantially vertical axis.  
         [0049]     Preferably the base unit is provided with a frame or track along which it can be moved laterally.  
         [0050]     Preferably the handling apparatus further comprises at least one pair of jaws for gripping an elongate member to be handled, said pair of jaws being operable between a more open configuration and a more closed configuration by a driven member moveable between a first position and a second position, wherein the relative motion of the jaws between the more open configuration and the more closed configuration is substantially in a plane, and the direction of movement of the driven member between the first and second positions is substantially perpendicular to said plane.  
         [0051]     It will be understood that the base unit may include two or more parts without departing from the scope of the invention. For example providing first and second parts which might be considered to be separate base units, with a first elongate support coupled to the “first” base unit and a second elongate support coupled to the “second” base unit is an option that should be considered to fall within the scope of the first and second aspects, and of the claims relating to these aspects.  
         [0052]     According to a third aspect of the present invention there is provided a handling apparatus which includes at least one pair of jaws for gripping an elongate member to be handled;  
         [0053]     wherein said at least one pair of jaws are operable between a more open configuration and a more closed configuration by a driven member which can be moved between a first position and a second position;  
         [0054]     and wherein the jaws operate substantially in a plane, and the direction of movement of the driven member between the first position and the second position is substantially perpendicular to said plane.  
         [0055]     Preferably the handling apparatus comprises at least two pairs of jaws.  
         [0056]     Preferably said at least two pairs of jaws operate in substantially parallel planes.  
         [0057]     Preferably the driven member is connected to at least one jaw of a pair of jaws by a link assembly.  
         [0058]     The driven member may be driven by fluid pressure.  
         [0059]     The driven member may be part of a piston assembly.  
         [0060]     The driven member may be part of a hydraulic piston assembly.  
         [0061]     The axis of the piston is preferably substantially perpendicular to the plane in which the jaws operate.  
         [0062]     The link assembly preferably connects the driven member to each of the jaws of a pair of jaws.  
         [0063]     The link assembly is preferably arranged so that as the part of the driven member which is attached to the link assembly is moved away from the plane of the jaws, at least one part of the link assembly is drawn towards a centreline of the jaw assembly. Thus the jaws may be forced together. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0064]     Preferred embodiments of aspects of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:  
         [0065]      FIG. 1  is a side view of a handling apparatus, in the form of a drill rod handler, in a first position;  
         [0066]      FIG. 2  is a side view of the drill rod handler of  FIG. 1  positioned to take a drill rod from an inclined mast;  
         [0067]      FIG. 3  is an enlargement showing the drill rod handler as shown in  FIG. 2 ;  
         [0068]      FIG. 4  is a side view of the drill rod handler of FIGS.  1  to  3  stacking a first drill rod in a rod stacking frame;  
         [0069]      FIG. 5  is an enlargement of the drill rod handler as shown in  FIG. 4 ;  
         [0070]      FIG. 6  is a side view of the drill rod handler of FIGS.  1  to  5  stacking a rod in a stacking frame which is almost full;  
         [0071]      FIG. 7  is an enlargement of the drill rod handler as shown in  FIG. 6 ;  
         [0072]      FIG. 8  is a side view of the drill rod handler arranged and positioned to pick up a substantially horizontal drill rod;  
         [0073]      FIG. 9  is a side view corresponding to a short time after the rod handler of  FIG. 8  has picked up the drill rod, illustrating how the handler and rod have moved;  
         [0074]      FIG. 10  is a side view corresponding to a short time after the position shown in  FIG. 9  has occurred, and illustrating the handler having moved the drill rod to a vertical orientation for loading into a rotation head;  
         [0075]      FIG. 11  is an enlargement of the drill rod handler as shown in  FIG. 10 ;  
         [0076]      FIG. 12  is a side view of a drill rod handler about to be used for taking drill rods from a vertical mast and placing them in a rod stacking frame;  
         [0077]      FIG. 13  is a side view of the drill rod handler engaging a vertical drill rod at a vertical mast;  
         [0078]      FIG. 14  is an enlargement of the drill rod handler as shown in  FIG. 13 ;  
         [0079]      FIG. 15  is a side view of the drill rod handler having moved a drill rod from the vertical mast to an empty rod stacking frame;  
         [0080]      FIG. 16  is an enlargement of the drill rod handler as shown in  FIG. 15 ;  
         [0081]      FIG. 17  is a side view of the drill rod handler placing a drill rod in the frame shown in  FIG. 15 , when the frame is almost full;  
         [0082]      FIG. 18  is an enlargement of the drill rod handler as shown in  FIG. 17 ;  
         [0083]      FIG. 19  is a side elevation of part of a handling apparatus, in the form of a drill rod handler, showing a retaining mechanism including two pairs of jaws for gripping a drill rod;  
         [0084]      FIG. 20   a  is a plan view of a pair of jaws, and corresponding operating mechanism, of the mechanism of  FIG. 19  in an open configuration;  
         [0085]      FIG. 20   b  is a side view of the operating mechanism for the jaws in the configuration shown in  FIG. 20   a;    
         [0086]      FIG. 21   a  is a plan view of a pair of jaws and corresponding operating mechanism in a more closed configuration; and  
         [0087]      FIG. 21   b  is a side view of the operating mechanism for the jaws in the configuration shown in  FIG. 21   a.   
     
    
     DETAILED DESCRIPTION OF EMBODIMENTS  
       [0088]     With reference to the drawings, a preferred embodiment of a handling apparatus in the form of a drill rod handler, generally designated  100 , is illustrated in FIGS.  1  to  7  in a configuration suitable for, and in the stages of taking drill rods  70  (one at a time) from an inclined mast  75  and stacking the drill rods in a rod stacking frame  80 .  
         [0089]     As shown in FIGS.  1  to  8 , and with particular reference to  FIG. 1 , the drill rod handler  100  comprises a base  102  and first and second support members in the form of respective first and second arms  104 ,  204 . The arms  104 ,  204  are pivotally attached to the base  102  at their respective first ends  106 ,  206  and are pivotally attached to a first link in the form of an elevator frame  110 , at their respective second ends  108 ,  208 . The pivotal attachments of the arms  104 ,  204  are spaced apart appropriately, and the arms  104 ,  204  are dimensioned so that the arms remain parallel in use, and consequently the orientation of the elevator frame  110  remains constant in use, irrespective of changes in the angle of elevation of the arms  104 , 204 .  
         [0090]     Providing two parallel arms provides greater load bearing capacity than would a single arm, and allows long rods to be handled.  
         [0091]     The arms  104 ,  204  can be moved by a driving mechanism in the form of first and second hydraulic cylinders  120 ,  130 . The first hydraulic cylinder is pivotally attached to the base  102  at a first end  122  thereof and is pivotally attached to a first end  142  of a floating support  140  at the second end  124  of the first hydraulic cylinder  120 . The first end  132  of the second hydraulic cylinder  130  is attached to the first end  142  of the floating support  140 , and the second end  134  of the second hydraulic cylinder  130  is attached to the first arm  104 . The second end  144  of the floating support  140  is pivotally attached to the base  102 . Retracting of one or both of the hydraulic cylinders  120 ,  130  pulls the arms  104 ,  204  and elevator frame  110  into a more elevated position, so that the elevator frame is laterally relatively close to the base  102 .  
         [0092]     The elevator frame  110  is pivotally attached to a second link member in the form of a loader tilt arm  150 , by a pivot arrangement  152 . However, as illustrated in FIGS.  1  to  8 , the elevator frame  110  and the loader tilt arm  150  can be prevented from relative pivotal movement by insertion of a locking insert pin  154  which passes through coaxially aligned apertures in the elevator frame  110  and the loader tilt arm  150 .  
         [0093]     The loader tilt arm  150  is pivotally attached to an elongate frame in the form of a loader head frame  160 . The loader head frame is provided with first and second sets of jaws  162 ,  164 , which are spaced apart by a spacer  166 . A head cylinder  168  is operable to move the spacer  166  and jaws  162 ,  164  along the loader head frame  160 .  
         [0094]     A third hydraulic cylinder  170  is provided for driving relative pivotal movement of the elevator frame  110  and the loader tilt arm  150  (although it cannot be effectively operated while the locking insert pin  154  is in position).  
         [0095]     A fourth hydraulic cylinder  180  is provided to drive relative pivotal movement of the loader tilt arm  150  and the loader head frame  160 .  
         [0096]     As the orientation of the elevator frame  110  (in the plane of the arms  104 , 204 ) is constant during use, when the locking insert pin  154  is in position, the orientation of the loader tilt arm  150  is also constant, so the orientation of the loader head frame  160  can be determined by the fourth cylinder  180  which can control the orientation of the loader head frame relative to the loader tilt arm  150 . Adjustable stops or rotation limiters  182 ,  184  are provided on the loader tilt arm  150  to allow desired extremes of orientation of the loader head frame  160  to be preset prior to use of the rod handler  100 .  
         [0097]     As shown in FIGS.  2  to  7 , the rod handler  100  can be used to take rods from an inclined mast  75  of any of a wide range of angles of inclination—about 45 degrees to 90 degrees for the illustrated embodiment—and place them in the rod stacking frame  80 .  
         [0098]     The base  102  is pivotable about a vertical axis by a hydraulic motor  190  and is moveable laterally along a track structure  193  upon which it is mounted, by a transverse motor  195 , so as to be able to allow the rod handler to access both the mast  75  and the rod stacking frame  80 .  
         [0099]     As shown in  FIGS. 1 and 4  to  7  the fourth cylinder  180  is retracted so that the loader head  160  comes into contact with the stop  182  which is adjusted prior to use to provide the correct orientation of the loader head  160  to stack a rod in a stacking frame with a given known racking angle.  
         [0100]     As shown best in  FIGS. 2 and 3  the fourth cylinder  180  can be extended so that the loader head  160  comes into contact with the stop  184  which is adjusted prior to use to provide the correct orientation of the loader head  160  to correspond to the orientation of the mast  75 .  
         [0101]     Use of the adjustable stops  182 , 184  thus allows rods  70  to be moved between a mast  75  and a stacking frame  80  without requiring an operator to exercise great skill in orienting the loader head to the correct rod orientation for each rod.  
         [0102]     Although as shown in FIGS.  1  to  7 , the orientation of, for example, the loader tilt arm  150  remains constant, it will be appreciated that its elevation changes as the orientation of the arms  104  varies. This can be compensated by using the head cylinder  168  to alter the elevation of the jaws  162 ,  164  relative to the loader head frame  160 , as can be seen by a comparison of  FIGS. 5 and 7 .  
         [0103]     FIGS.  8  to  11  show the rod handler  100  being used for loading drill rods  70  from a stack in which they are orientated horizontally, and operating to load them into a vertical rotation head. The important difference between this operation and the operation illustrated in FIGS.  1  to  7  is that in order to pick up horizontal rods the locking insert pin  154  is removed. This allows the loader tilt arm  150  to be pivoted relative to the elevator frame  110  by the third cylinder  170 , providing a greater range of movement of the loader head frame  160 . Apertures  150   a,    110   a  which were (as illustrated in FIGS.  1  to  7 ) held together by the insert locking pin  154 , have been moved apart as shown in  FIG. 8 .  
         [0104]     The operations involved in loading drill rods  70  from a stack in which they are orientated horizontally, and operating to load them into a vertically orientated rotation head are illustrated by and explained with reference to FIGS.  8  to  11 . It is perhaps worth noting that because the fourth cylinder  180  can be locked in a predetermined position (using needle valves in a preferred embodiment), the loader head frame  160  is locked in a predetermined position relative to the loader tilt arm  150 , and orientation of the loader head frame  160  and rod  70  are determined by operation of the third cylinder  170 .  
         [0105]     As shown in  FIG. 8 , the third cylinder  170  is retracted, corresponding to the loader head frame  160  being in a horizontal orientation.  
         [0106]     As shown in  FIG. 9  the third cylinder is partially extended to rotate the loader head frame  160  into an inclined orientation, and at the same time the first and second cylinders  120 , 130  are retracted to elevate the elevator frame  110 , loader tilt arm  150  and loader head frame  160 .  
         [0107]     As shown in  FIGS. 10 and 11 , the motor  190  rotates the arms  104 , 204 , elevator frame  110 , loader tilt arm  150  and head frame  160 , typically 180 degrees about a vertical axis to move the rod  70  to the mast. Simultaneously the third cylinder continues to extend, until (in this example) the drill rod  70  is vertical, and the first and second cylinders  120 , 130  continue to retract to elevate the rod and adjust the horizontal distance between the rod  70  and the base  102 .  
         [0108]     As shown in  FIG. 11  the rod  70  can be lowered by operation of the head cylinder  168 .  
         [0109]     FIGS.  12  to  18  show the rod handler  100  being used for taking rods from a vertical mast  75   a  and placing them in a rod stacking frame  80 . Similarly to the situation shown in FIGS.  1  to  7 , the insert locking pin  154  is used to pivotally lock the loader tilt arm  150  and the elevator frame  110 , and prevent operation of the third cylinder  170 . The upper stop  182  can be used to preset the vertical rod position, and the lower stop  184  to preset the angle for racking. The operations involved in taking rods from a vertical mast and placing them in a rod stacking frame are illustrated by and explained with reference to FIGS.  12  to  18 .  
         [0110]     The operations are not dissimilar from those described with reference to  FIG. 1  to  8 .  FIG. 12  shows the rod handler  100  in the same configuration as in  FIGS. 15 and 16 , but, for clarity, without the vertical mast  75   a  or rod stacking frame  80 .  
         [0111]     With reference to  FIGS. 13 and 14  the fourth cylinder  180  is retracted until the loader head frame  160  (and the rod  70 ) is vertical, a position which is determined by previous adjustment of upper stop  182 . This orients the loader head frame for removal of a rod  70  from the vertical mast  75   a.    
         [0112]     As shown in  FIGS. 12, 15  and  16 , the fourth cylinder  180  is extended until the loader head frame  160  contacts the lower stop  184 , which has been preset to give the correct angle for racking.  
         [0113]     The transverse motor  195  is used to move the rod handler  100  between the mast and the rod stacking frame  80 .  
         [0114]     It will be appreciated from the description above how operation of the first and second cylinders  120 , 130  and head cylinder  168  effects the elevation and reach of the arms  104 , 204 , loader head frame  160  and rod  170 , so that the rod handler can stack rods  70  onto a rod stacking frame which is empty (as in  FIGS. 15 and 16 ) or substantially full (as in  FIGS. 17 and 18 ).  
         [0115]      FIG. 19  shows the loader head frame  160 , head cylinder  168 , and jaws  162 ,  164  in more detail.  
         [0116]      FIGS. 20   a  to  21   b  illustrate how the jaws  162  are operated. The jaw arrangement  162  is designed to be compact in order to allow access to rods when, for example, there is a rod close to either side of the rod it is desired to pick up using the jaws  162 .  
         [0117]     Each of the first and second jaw elements  220 ,  240  of the pair of jaws is mounted to a respective first or second jaw holder  228 ,  248 , by jaw pins  222 . This allows easy replacement of the vulnerable jaw elements  220 ,  240 . Each jaw holder  228 ,  248  is pivotably mounted to a mounting plate  227 , via an insert  230 , such that pivoting of the jaw holders  228 ,  248  allows the jaws to open or close. The jaws are operable by a hydraulic cylinder  201  which passes between the jaw holders  228 ,  248 , in order to provide a compact configuration. The hydraulic cylinder  201  is attached at each of its ends  202  to a pair of plate links  209 , and respective first and second plate links  209  of each pair are attached to the first and second jaw holders  228 ,  248 . When the cylinder  201  is extended, or stroked out, as shown in  FIGS. 21   a  and  21   b,  the distal ends of the first and second plate links  209  of each pair are forced away from each other, and the ends of the plate links  209  which are attached to first and second jaw holders  228 ,  248  are consequently pulled in towards the axis of the cylinder  201 , thus clamping the jaws. It is desirable to have the cylinder aligned substantially perpendicular to the plane of the jaws in order to keep the jaw arrangement compact and help avoid the cylinder obstructing access by the jaws to objects to be grasped. In order to balance forces within the mechanism, the cylinder  201  is able to float through bushes  232  provided in the mounting plate  227 . The cylinder contains a spring to bias it to its extended position, so the jaws are closed, or kept closed in the event of a hydraulics failure. It will be appreciated that hydraulic retraction of the cylinder, as shown in  FIGS. 20   a  and  20   b,  will cause the jaws to open allowing release of an object held.  
         [0118]     It will be appreciated that in some contexts (such as, for example, the following claim  1 ) the head assembly may be considered to include (but is not limited to embodiments including) the loader tilt arm  150  and the elevator frame  110  or links that have at least some functions in common with those elements.  
         [0119]     This application claims priority from Australian Provisional Application No. 2004903011 the entire disclosure of which is hereby incorporated herein by reference.  
         [0120]     Modification and improvements may be made to the described embodiments without departing from the scope of the invention as claimed.  
         [0121]     It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or in any other country.  
         [0122]     In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.

Summary:
A handling apparatus comprising: a base unit; a first elongate support pivotally coupled at a first end to the base unit; a second elongate support pivotally coupled at a first end to the base unit; a head assembly for releasably retaining an elongate member, said head assembly being supported, in use, by the first and second elongate supports; wherein the first and second elongate supports are pivotally coupled to the head assembly at respective second ends thereof; and whereby the first and second elongate supports can pivot relative to the base unit whilst remaining substantially mutually parallel with at least part of the head unit maintained in a substantially constant orientation.