Cross Reference to Related Application

This application claims priority to U. S. Provisional Patent Application 62/487, 162 filed April 19, 2017, which is hereby incorporated by reference in its entirety. Field of the Invention

This invention relates to an apparatus for percussive, long-hole and down-the- hole drilling operations.

Background

Drilling rigs used in percussive, long-hole and down-the-hole (DTH) drilling operations require that drilling rods be added and removed from the drill string during drilling. It is advantageous to automate rod handling as it increases the safety and efficiency of the operation. However, known automated handling systems are positioned to the side, the top or in front of the drill. This exposes the moving parts of the handling system, creating a hazard to personnel. Such systems are furthermore not compact and require extensive mine excavation to permit the drilling axis of the drill to be aligned as desired. There is clearly an opportunity to improve the safety of rod handling systems and reduce the need for extensive mine excavation by improvements to automated rod handling devices.

Summary The invention concerns an apparatus for percussive, long-hole and down-the-hole drilling using drilling rods. In one example embodiment the apparatus comprises a frame. The frame defines an envelope surrounding a central space. A drill is mounted on the frame for movement along a drilling axis. A magazine is mounted on the frame within the envelope and adjacent to the drill. The magazine is for holding a plurality of the drilling rods and is rotatable about a magazine axis oriented parallel to the drilling axis to present and receive the drilling rods respectively to and from the drill. A pick and place mechanism is mounted on the frame between the drill and the magazine. The pick and place mechanism has a drilling rod engaging body movable between the magazine and the drill for moving the drilling rods between the magazine and the drill.

In an example embodiment, the magazine comprises an axle rotatably mounted on the frame. The axle is arranged coaxially with the magazine axis. First and second plates are mounted on the axle and arranged transversely thereto. The first and second plates are arranged in spaced relation to one another lengthwise along the axle. A plurality of support blocks are mounted on the first and second plates. Each block is adapted to engage and support one of the drilling rods. First and second static rings are mounted on the frame and are positioned proximate to respective opposite ends of the axle. Each static ring has a rim skirt extending circumferentially therearound and extending axially therefrom. The rim skirts overlie ends of the pipe elements when they are supported on the support blocks. A door is mounted on one of the static rings. The door is openable to release one of the rods when the one rod is aligned with teh door. In an example embodiment, the pick and place mechanism comprises an electro- actuated magnet mounted on a swing arm pivotably mounted on the frame. The swing arm pivots about a pivot axis oriented parallel to the drilling axis. The electro-actuated magnet is rotatable relatively to the pivot arm about a rotation axis oriented parallel to the drilling axis. In a practical example, the electro-actuated magnet is based upon a manually operated lifting magnet, Eriez Model RPL-22. A hydraulic rotary actuator is coupled to the magnet mechanism in place of a manually actuated lever. The system sends an electrical signal to a hydraulic valve that, in turn, rotates the rotary actuator to engage and disengage a rare earth magnet which comprises the lifting magnet.

In an example embodiment the apparatus further comprises an indexing mechanism for incrementally rotating the magazine about the magazine axis. In a specific example embodiment the indexing mechanism comprises a Geneva wheel or other indexing apparatus. The Geneva wheel may be coupled to the magazine with a gear train or via an endless chain. A further example embodiment comprises a chassis. A first carriage is mounted on the chassis and is movable relatively thereto in a first direction. A second carriage is mounted on the first carriage and movable relatively thereto in a second direction oriented perpendicularly to the first direction. A first turntable is mounted on the second carriage and rotatable relatively thereto about a first axis oriented perpendicularly to both the first and second directions. A second turntable is mounted on the first turntable and rotatable relatively thereto about a second axis oriented perpendicular to the first axis, wherein the frame is mounted on the second turntable, the frame being pivotably movable relatively to the second turntable about a third axis oriented perpendicular to the first and second axes.

In an example embodiment the chassis comprises a wheeled trailer. Further by way of example, the drill comprises a hydraulic hammer drill or down-the-hole drill. The apparatus may also comprise a rod breaker mounted on the frame along the drilling axis. By way of further example, the apparatus may comprise a rod clamp mounted on the frame adjacent to the rod breaker.

The invention also encompasses an apparatus for handling drilling rods. In one example embodiment the apparatus comprises a support frame. A magazine is rotatably mounted on the frame. The magazine is configured to hold and dispense the drilling rods. An indexing mechanism is used to rotate the magazine incrementally through a series of angular displacements. By way of example, the indexing mechanism may comprise a Geneva wheel or a stepper motor, or other indexing mechanism.

Brief Description of the Drawings

Figure 1 is an isometric view of an example embodiment of a mobile drilling rig according to the invention; Figure 2 is an isometric view of an example drilling and automated rod handling apparatus shown in Figure 1 ; Figure 3 is an isometric view of a portion of the drilling and automated rod handling apparatus shown in Figure 2;

Figure 4 is an isometric view of an example rod magazine according to the invention; Figure 4A is an isometric view of a portion of the rod magazine shown in Figure

4;

Figure 5 is an end view of the portion of the drilling and automated rod handling apparatus shown in Figure 3;

Figure 5A is an end view of an alternate embodiment of the portion of the drilling and automated rod handling apparatus shown in Figure 3; and

Figure 6 is a detailed view of an example pick and place mechanism used with the drilling and automated rod handling apparatus shown in Figure 3.

Detailed Description

Figure 1 shows an example mobile drilling rig 10 according to the invention. Rig 10 comprises a tractor unit 12 which provides power to move the rig and run its various hydraulic and electrical systems. A wheeled trailer 14 is joined to tractor unit 12. A drilling apparatus 16 is mounted on the trailer 14. Trailer 14 comprises a chassis 18 upon which a first carriage 20 is mounted. As shown in Figure 2, carriage 20 is movable in a first direction, defined as the "X" direction 22. Motion of carriage 20 is effected by a hydraulic actuator 24 mounted on the carriage 20. A second carriage 26 is mounted on the first carriage 20. Second carriage 26 is movable in a second, defined as the "Y" direction 28. Second direction 28 (Y) is oriented perpendicular to the first direction (X). Motion of the second carriage 26 is effected by a hydraulic actuator 30 mounted on the carriage 26. A first turntable 32 is mounted on the second carriage 26. The first turntable rotates about a first axis, defined as the "Z" axis 34. The Z axis 34 is perpendicular to both the X and Y directions 22 and 28. Rotation of the first turntable 32 is effected by a hydraulic actuator 36 acting between the first turntable and the second carriage 26. A second turntable 38 is mounted on the first turntable 32. Second turntable 38 rotates about a second axis oriented parallel to the Y direction and defined as the "Y" axis 40. Rotation of the second turntable is effected by hydraulic actuators 42 acting between the first and second turntables 32 and 38. A frame 44 is mounted on the second turntable 38. Frame 44 rotates about a third axis oriented perpendicular to both the first (Z) axis 34 and the second (Y) axis 40 and defined as the "X" axis 46. Rotation of the frame 44 is effected by hydraulic actuators 48 operating through pairs of pivot arms 50 attached on opposite sides of the frame between frame 44 and the second turntable 38. A hydraulic rock drill 52 is mounted on frame 44. A rod breaker 54 is also mounted on frame 44 along with a rod clamp 56 (see also Figure 1). The drill 52 is movably mounted on the frame 44 toward and away from the rod breaker 54 and the rod clamp 56 along a drilling axis 58. Motion of the drill 52 is effected by hydraulic actuators 60 operating between the frame 44 and the drill. Motion of the drill along the drilling axis 58 permits the drill bit (not shown) to be advanced or withdrawn, as drilling rods 62 are added to or withdrawn from the drill string (not shown).

As shown in Figure 3, drilling rods 62 are stored in a magazine 64 mounted on frame 44 adjacent to the drill 52. As shown in Figures 4 and 4A, the magazine 64 comprises first and second plates 65 and 66 mounted on an axle 68 at points intermediate its ends. Axle 68 is oriented parallel to the drilling axis 58 and defines a magazine axis 70 about which the magazine rotates. The first and second plates 65 and 66 rotate with axle 68. A plurality of support blocks 72 are mounted on the circumference of first and second plates 65 and 66. Each support block forms a "U" shaped receptacle adapted to receive and support drilling rods 62. As further shown in Figures 4 and 4A, first and second static rings 71 and 73, mounted on the frame 44 (see Figure 3) are positioned proximate to respective opposite ends of the axle 68. The static rings 71 and 73 are fixedly mounted on the frame 44 and do not rotate with axle 68. Each static ring 71 , 73 comprises a respective rim skirt 75 which extends circumferentially around each ring. The rim skirts 75 on each ring 71 and 73 project axially toward the first and second plates 65 and 66. A door 77 is positioned in the static ring 71. The door 77 is openable and closeable using an actuator 79 (see Figure 4) also fixedly mounted on the frame 44. The drilling rods 62 are supported by the support blocks 72 on plates 65 and 66 and captured between the static plates 71 and 73 and thereby retained within the magazine 68. The rods 62 are constrained circumferentially by the support blocks 72 as well as axially and radially at opposite ends by the rim skirts 75 and the static rings 71 and 73. While the rods are constrained axially and radially they are permitted to rotate relative to the static rings 71 and 73 with the first and second plates 65 and 66 when the axle 68 rotates about axis 70. Rotation of axle 68 permits each rod 62 to be aligned with door 77 for removal of a rod from the magazine 64. The plates 65 and 66 may also be rotated align an empty position on the plates 65 and 66 with the door 77 to permit a rod to be returned to and stored in the magazine 64.

As shown in Figure 5, rotation of the magazine 64 is effected by a hydraulic motor 74, for example a Gerotor operating through a Geneva wheel 76. The Geneva wheel has a pinion 78 which turns a gear 80 mounted on the axle 68 through an endless chain 82. In an alternate embodiment, shown in Figure 5 A, a gear train 83 may be used instead of the endless chain. The ratio between the pinion 78 and the gear 80 is established so that when the Geneva wheel makes a quarter turn in response to a revolution of the motor 74 the magazine rotates through an angular displacement equal to 1/n of a complete circle, where "n" equals the number of rods which the magazine can hold. In the example shown n=20, thus for each turn of the motor 74 the magazine rotates through 1/20 of a circle or 18°. Each rotation of the Geneva wheel 80 positions the magazine 64 so that it can present or receive a rod 62 to be engaged by a pick and place mechanism 84, shown in Figures 5 and 6. The Geneva wheel 76 is an example of an indexing mechanism used to incrementally rotate the magazine 64 through a series of angular displacements. Other example indexing mechanisms, such as stepper motors, are also feasible.

As shown in Figure 6, the pick and place mechanism 84 comprises a pair of swing arms 86 mounted on the frame 44. Swing arms 86 are driven by a rotary actuator 88 and pivot about a swing arm axis 90 oriented parallel to the axis 70 of magazine 64 (see Figure 4). A rod capture device 92 extends between the swing arms 86 and is rotatable about a capture axis 94 oriented parallel to the swing arm axis 90. Rod capture device 92 is also movable axially along the capture axis 94 via actuator 99 as explained below. Rotation of the capture device 92 is effected by a rotary actuator 96 mounted on one of the swing arms 86. Figure 5 shows the trajectory 98 of the capture device 92 as it is pivoted about swing arm axis 90 and rotates about the capture axis 94 (see Figure 6). The combined motion of the swing arms 86 and the rod capture device 92 on the swing arms 86 permits the rod capture device to move a rod 62 between the magazine 64 and the drill 52 (see Figure 3). In this example embodiment the capture device 92 comprises an electro-actuated magnet 100. In a practical example, the electro-actuated magnet 100 is based upon a manually operated lifting magnet, Eriez Model RPL-22. A hydraulic rotary actuator is coupled to the magnet mechanism in place of a manually actuated lever. The controller 102, in this example mounted on the tractor unit 12 (see Figure 1) sends an electrical signal to a hydraulic valve that, in turn, rotates the rotary actuator to engage and disengage a rare earth magnet which comprises the lifting magnet. With reference to Figures 4-6, removal of a rod 62 is accomplished via the pick and place mechanism 84 and starts with rotation of the magazine 64 to align the desired rod 62 with the door 77 in the fixed plate 73. The pick and place mechanism 84 is pivoted and rotated to engage the rod capture device 92 with the desired rod 62 and the door is opened by actuator 79. The rod capture device 92 is actuated to grip the rod, in this example magnetically. The rod 62 is them moved axially along axis 94 through the now open door 77 until its end clears rim skirt 75 on static ring 73, at which point the rod capture device can be pivoted about axis 90 to move radially away from the magazine 64 and then rotated about axis 94 to place the rod 62 in the drill string. The door 77 is then closed to permit further rotation of the magazine 64 while still constraining the remaining rods 62.

Coordination of the various hydraulic actuators and motors as well as the electro- actuated magnet 100 of the pick and place mechanism 84 is afforded by a microprocessor based controller 102, for example a programmable logic controller mounted in the tractor unit 12. As shown in Figure 1, the drilling rig 10 is operated remotely using a control stand 104 which, in this example, communicates wirelessly over a communication bus with the controller 102 on the rig.

In operation the rig 10 is maneuvered into position with the frame 44 adjacent to a plurality of rock faces to be drilled. The frame 44 may be moved linearly in the X and Y directions 22 and 28 by motion of carriages 20 and 26, and rotated about the Z axis 34 by rotation of the first turntable 32, rotated about the Y axis 40 by rotation of the second turntable 38, and rotated about the X axis 46 by the motion of pivot arms 50 so as to align the drilling axis 58 as desired relatively to the rock face. Magazine 64 is rotated using the Geneva wheel 76 to position a rod to be received by the capture device 92 of the pick and place mechanism 84. Swing arms 86 rotate about the swing arm axis 90 and the capture device 92 rotates about the capture axis 94 to remove a rod 62 from the magazine and position it on the drilling axis 58. Drill 52 is then moved along the drilling axis 58 to engage the rod 62. The action of the drill 52 is coordinated with the rod clamp 56 to add rod 62 to the drill string. The operation of the magazine 70 and the pick and place mechanism 84 are repeated, along with operation of the rod clamp 56 to add rods 62 to the drill string.

It is advantageous to mount the rod breaker 54 on the frame 44 to automate the process pulling rods to disassemble the drill string. The process starts with the rock drill 52 coupled to the drill string in the hole. No water is at the bit, and the rods are not rotating. Drill 52 is then retracted along drilling axis 58 utile is reaches the rod breaking position, whereupon the rod clamp 56 is closed. Rod breaker 54 is retracted and then closed on the mid body of the rod. The rod breaker grip is activated and the rod breaker 54 is rotated. The rod breaker clamp is then opened and the rod breaker is then rotated. The rod is then grasped by the rod capture device 92 of the pick and place mechanism 84 which rotates about axis 94 an pivots about axis 90 to bring the rod 62 to the magazine 64. Meanwhile, the magazine 64 has rotated to position empty support blocks 72 on plates 65 and 66 in alignment with door 77 of the static ring 71. Actuator 79 opens the door 77 which permits the rod capture device 92 to clear the rim skirt 75 of static ring 71 and position rod 62 onto the support blocks 72. The rod capture device then moves axially along axis 94 via actuator 99 so that an end of the rod 62 is captures by static ring 73 and its rim skirt 75. Door 77 is then closed, thereby capturing the rod between the static rings 71 and 73 (and their rim skirts 75) while further constrained by support blocks 72 on plates 65 and 66. The rod capture device 92 is then deactivated to release the rod 62, and the pick and place mechanism 84 can move back to collect the next rod broken from the drill string.

Of significant advantage is the placement of the magazine 64 within a central space 106 defined by the envelope 108 of the frame 44 and the drill 52 (see Figures 1 , 2 and 5). As shown in Figure 1, the magazine 64 is between the drill 52 and the pivot arms 50 mounted on opposite sides of the frame, thereby defining its envelope. By housing the magazine within the envelope 108 of frame 44 the following advantages are achieved: 1) the hazard to personnel caused by motion of the magazine 64 and motion of the drill rods 62 between the magazine 64 and the drill 52 is reduced; 2) a positioning "dead zone" for feeding the drill string is avoided; 3) the design is compact and requires less excavation.

The use of an electro-actuated magnet 100 with the pick and place mechanism 84 is advantageous as it provides a compact design with few moving parts. Additional advantage is secured by using the rotating magazine, which permits the rig to handle rods of different length and diameters, affording significant versatility to the drilling rig. Proximity sensors may also be integrated into the rig to improve rod handling. The sensors can be used to sense the presence or absence of a rod at a specific position on the magazine.