Coring apparatus

Abstract

20 25 28 72 64 23 D ec 2 02 5 A B S T R A C T 2 0 2 5 2 8 7 2 6 4 2 3 D e c 2 0 2 5 A B S T R A C T 2 0 2 5 2 8 7 2 6 4 2 3 D e c 2 0 2 5

Description

FIG. 3 is a schematic top plan view of the coring assembly of the coring apparatus of FIG. 1; FIG. 4 is a cross sectional view taken along line 4-4 of FIG 2; and FIG. 5 is a schematic diagram of a hydraulic control system of the coring apparatus of FIG. 1. Description of Embodiments

[0023] Referring to the drawings, there is shown a coring apparatus 10. The coring apparatus 10 comprises a coring assembly 100 and a mobile construction machine, in the form of a skid-steer machine, such as a skid-steer loader or multi-terrain loader 200, to which the coring assembly 100 is mounted.

[0024] The coring assembly 100 comprises a stabilising stand 110 having a base 112 for resting on a surface 300 in which a core is to be drilled by the coring apparatus 10, and a frame 114 fixedly connected relative to and extending upwardly from the base 112. The base 112 has a length L and a width W defining a rectangular footprint of length L and width W, wherein the width of the base 112 defines a first direction D1 and the length of the base defines a second direction D2 perpendicular to the first direction. Three anchor points 116a, 116b are provided on the stand 110 to facilitate connection of the coring assembly 100 to a three point hitch of the mobile construction machine 200. Anchor points 116a are spaced apart from one another in direction D1 and anchor point 116b is offset from a line drawn between anchor points 116a. The illustrated coring assembly 100 is configured for use with coring bits of up to 600mm (approx 24 inches) in diameter. To facilitate stability of assembly 100 in use, the length L and width W of the base 12 are both at least 1.2 times the diameter of the largest diameter coring bit that can be used by the assembly 100. For example, in the illustrated embodiment, the width W is approximately 1300mm and the length L is approximately 900mm. 2025287264   23 Dec 2025

[0025] Coring assembly 100 comprises a rotatable drill shaft 120 adapted to have a coring bit 130 fastened thereto. The drill shaft 120 has a longitudinal axis A along which it is moveable relative to the base 112. Axis A extends through the footprint of base 112. An input drive, comprising a motor 140 and associated gearbox 150, is provided for rotating the drill shaft 120. In the illustrated embodiment, coring bit 130 has a diameter of 600mm.

[0026] The drill shaft 120, motor 140 and gearbox 150 are carried by a carriage 160 that is slidably mounted on rails 118 attached to the frame 114. The rails 118 extend in a direction substantially perpendicular to a plane P defined by the base 112. An actuator 170 extends between the carriage 160 and an upper mounting point 114a on the frame 114 for moving the drill shaft 120, as well as motor 140 and gearbox 150, relative to the base 112 along the longitudinal axis A. The carriage 160 includes a platform 162 that extends from the frame 114 in a direction substantially parallel to plane P. The motor 140 and gearbox 150 are mounted on an upper side of the platform 162 and the drill shaft extends from its lower side. In use, the coring bit 130 carried by the drill shaft 120 passes through an opening O defined in the base 112.

[0027] In terms of axes defined by the first direction D1 and second direction D2, the longitudinal axis A of the drill shaft 120 is offset from a centre of the base 112 by a distance of no more than 0.3 times the diameter of the largest diameter coring bit that can be used by the assembly 100. In the illustrated embodiment, axis A is offset from the centre of the base 112 by a distance of approximately 150mm (approx 6 inches). Moreover, a longitudinal axis of the frame 114 and axis A are offset on opposite sides of the centre of the base 112. As such, the footprint of the base 112 substantially surrounds the coring bit 130, in use.

[0028] The stroke of the drill shaft 120 (i.e., its range of motion along the longitudinal axis A relative to the base 112) carries a lower end of the drill shaft 120 from a point P1 at or below the level of surface 300 to a point P2 approximately 800mm above the surface 300. In the illustrated embodiment, point P1 is approximately 124mm below surface 300 and point P2 is approximately 790mm above surface 300. To facilitate this 2025287264   23 Dec 2025 range of motion, the stroke of drill shaft 130 in the illustrated embodiment is approximately 914mm. In other embodiments, the stroke of the drill shaft 112 may be other than 914mm, such as a different length stroke that is at least 500mm long, at least 600mm long, at least 700mm long, at least 800mm long or at least 900mm long, and less than 1500mm long, less than 1200mm long, less than 1100mm long or less than 1000mm long.

[0029] The coring apparatus 100 comprises hydraulically powered stabilisers 180 having an engaged configuration in which they engage a radially outer surface of the coring bit 130 to stabilise the coring bit during coring and a disengaged configuration in which they are disengaged from the coring bit. The stabilisers 180 comprise pivotable arms 180a actuated by linear actuators 180b, each arm having one or more rollers 180c at an end thereof. The rollers 180c engage the radially outer surface of the coring bit in the engaged configuration. The configuration of the arms when engaged with a 300mm coring bit 130’ is indicated by reference numeral 180a and the configuration of the arms when disengaged is indicated by reference numeral 180a’. Stabilisers 180 facilitate preventing coring bit 130 from rattling in operation, especially when it first contacts surface 300 and until the coring bit has sufficiently advanced below surface 300 to be self-stabilising. Arms 180a are mounted horizontally and rollers 180c engage coring bit 130 above, but ideally as close as possible to, surface 300.

[0030] Motor 140 is a hydraulic motor configured to output a torque of 13.3 Nm / MPa. An example of a suitable motor 140 is SunFab axial piston motor Model No. SCM084W-H-SC4-C14-V1M SAE, which has a displacement of 84 cm3 / rev and is configured for continuous operation at between 400 RPM and 4000 RPM, and at a working pressure of about 450 bar (approx 45 MPa). When operated at this working pressure, motor 140 outputs a torque of approximately 600 Nm. When operated at a lower pressure, such as at 17 MPa, motor outputs a torque of approximately 226 Nm. In other embodiments, a different motor 140 may be used, such as a motor: configured for continuous operation at a different RPM of above 200 RPM or above 300 RPM and up to 4500 RPM, up to 5000 RPM or up to 6000 RPM; 2025287264   23 Dec 2025 configured for continuous operation at a different working pressure of between 300 bar (approx 30 MPa) and 500 bar (approx 50 MPa); and / or having a different displacement of between 60 and 110 cm3 / rev, or of between 70 and 100 cm3 / rev, or of between 80 and 90 cm3 / rev.

[0031] The actuator 170 comprises a hydraulic ram. In the illustrated embodiment, the hydraulic ram 170 has a volume of approximately 8000cm3, comprising 6600cm3 on the side of its piston opposite from the hydraulic input and 1400cm3 on the hydraulic input side of the piston. This relatively large volume of the hydraulic ram 170 facilitates precise control over the axial position of the drill shaft 120, and thereby of the cutting end of the coring bit 130. In addition to controlling the axial position of the drill shaft 120, as well as the motor 140 and gearbox 150, along the longitudinal axis A, the actuator 170 also controls a force with which the coring bit 130 is pressed against the surface 300.

[0032] The gearbox 150 comprises a hydraulic pump drive. The gearbox 150 facilitates the rotational speed of the drill 120 shaft being selectively variable between 120 RPM, 230 RPM, 340 RPM, 580 RPM, 98 RPM and 1400 RPM. In the illustrated embodiment, the gearbox 150 produces an output ratio of 1.67:1 and is configured to handle an input torque from motor 140 of up to 1410 Nm. An example of a suitable gearbox 150 is Durst hydraulic pump drive Model No. 1PD06 / 07840. When the motor 140 is operated at its working pressure of 45 MPa, the motor outputs a torque of approximately 600 Nm, such that the motor and gearbox 150 supply a torque of approximately 1000 MPa to the drill shaft 120. When operated at a lower pressure, such as at 17 MPa, the motor 140 outputs a torque of approximately 226 Nm, such that the motor and gearbox 150 supply a torque of approximately 377 MPa to the drill shaft 120.

[0033] The mobile construction machine 200 comprises a hydraulic system having a plurality of hydraulic pumps 210 powered by a diesel engine 220. A first subset of the hydraulic pumps 210a is independent of a second subset of the hydraulic pumps of the mobile construction machine, wherein the first and second subsets may each include 2025287264   23 Dec 2025 one or more pumps. The pump(s) of the first subset is / are configured to supply pressurised hydraulic fluid independently to the motor 140, hydraulic ram 170 and stabilisers 180. This independence of hydraulic fluid supply facilitates the ram 170, motor 140 and stabilisers 180 being controlled accurately when both are operated simultaneously. Without independence of hydraulic fluid supply, operation of any one of the motor 140, ram 170 and stabilisers 180 can adversely affect operation of the others. The pump(s) of the first subset is / are variable displacement pump(s) and the pump(s) of the second subset is / are fixed displacement pump(s). In the illustrated embodiment, the first subset of the pumps includes a single pump and independent supply of hydraulic fluid therefrom to each of the motor 140, ram 170 and stabilisers 180 is facilitated by a hydraulic block (sometimes referred to as a hydraulic manifold) 190 of coring assembly 100. Hydraulic block 190 comprises valves for controlling supply of hydraulic fluid from the first subset of the pumps to each of the motor 140, ram 170 and stabilisers 180. Hydraulic block 190 is responsive to an electronic control unit (ECU) 195, which is located in an operator’s cabin of loader 200. The ECU 195 comprises a display screen that conveys operational data on the coring assembly 100 to the operator. In the illustrated embodiment, the display screen is touch enabled to facilitate the operator inputting data associated with controlling operation of the coring assembly 100. In other embodiments, a keyboard may be associated with ECU 195 to facilitate the entry of data by the operator. In the illustrated embodiment, joystick controls are also associated with the ECU 195 to facilitate actuation of stabilisers 180 and motor 140.

[0034] Coring assembly 100 also comprises a cooling system for preventing overheating of the coring bit 130 and drill shaft 120, and for lubricating the coring bit. In the illustrated embodiment, the cooling system comprises a nozzle for directing water to the coring bit 130 and drill shaft 120. ECU 195 controls actuation of the cooling system. Water flow to the nozzle is controlled via a mechanical pressure regulator responsive to ECU 195. The display screen of ECU 195 displays a warning if the flow rate sensor indicates water flow below a predetermined magnitude. 2025287264   23 Dec 2025

[0035] ECU 195 receives signals from various sensors to facilitate control of the coring assembly 100. For example, a sensor is associated with motor 140 to indicate the rotational speed of drill shaft 120; one or more pressure sensor is associated with ram 170 to indicate the downward pressure applied by ram 170, and thereby by coring bit 130 to the surface 300; one or more pressure sensor is associated with the actuators 180b of stabilisers 180; and a flow rate sensor is associated with the nozzle of the cooling system to provide cooling water flow rate information.

[0036] ECU 195 is programmed to control the drill shaft to rotate at a predetermined operational speed (RPM) based on the core diameter being used. Table 1 below shows the predetermined speeds associated with various core diameters: Core Diameter (mm) Predetermined Initial Speed (RPM) Predetermined Operational Speed (RPM) 0 - 50 100 1400 50 - 90 100 980 90 - 150 100 580 150 - 250 50 340 250 - 400 50 230 400 - 600 50 120

[0037] Operation of coring apparatus 10 will now be described. The operator enters the diameter of the coring bit 130 being used and the desired core depth via the touch screen of ECU 195. Based on the coring bit diameter entered, the ECU 195 controls the delivery of appropriate hydraulic pressure to motor 140 and gearbox 150, via hydraulic block 190, to cause the drill shaft to rotate at the associated predetermined speed once 2025287264   23 Dec 2025 coring operations have commenced. Once the relevant coring bit speed has been assigned by ECU 195, touch screen of ECU 195 displays a “Calibration Start” button, pressing of which enables the joystick controls for motor 140 and stabilisers 180. ECU 190 also facilitates control of the rotational direction of drill shaft 120, via hydraulic block 190. During coring operations, the display screen of ECU 195 displays various operational data, such as current coring depth, on / off status, rotational direction and rotational speed of drill shaft 120, engaged / disengaged status of stabilisers 180, downward pressure of coring bit 130 on surface 300, advance rate (linear speed) of coring bit 130, and on / off status of water flow to coring bit 130.

[0038] Prior to commencement of coring, the operator calibrates coring assembly 100 with the assistance of ECU 195. The calibration can be performed automatically or manually. Automatic calibration involves the operator inputting a command to lower coring bit 130 into contact with surface 300, which causes a sensor associated with the coring bit 130 to send a signal to ECU 195. Responsive to this signal, ECU 195 sets a zero depth associated with this axial position of the coring bit 130. Manual calibration involves the operator lowering the coring bit 130 to the axial position to be associated with zero depth thereof and instruct ECU 195, via its touch screen, to associate zero depth of the coring bit with this axial position. Once automatic or manual calibration has been performed, ECU 195 causes coring bit 130 to be raised relative to surface 300 by a predetermined distance, which in the illustrated embodiment is 30mm. ECU 195 prevents actuation of motor 140, and thereby rotation of drill shaft 120, until the calibration has been performed and coring bit raised by the predetermined distance. Once calibration has been performed and coring bit 130 raised by the predetermined distance, ECU 195 causes a “Proceed” button to be displayed on the touch screen. Pressing the “Proceed” button causes ECU 195 to enable motor 140 and, if the diameter of the coring bit 130 being used is greater than 200 mm, to control delivery of hydraulic fluid to actuators 180b of stabilisers 180 to move arms 180a into the engaged configuration in which rollers 180b engage the outer surface of coring bit 130. ECU retracts stabilisers 180 once coring bit 130 has achieved a sufficient depth to be selfstabilising. 2025287264   23 Dec 2025

[0039] Once calibration has been performed and, if relevant, stabilisers 180 have been engaged with coring bit 130, ECU 195 enables joystick controls for operator actuation of motor 140 and ram 170. ECU disables motor 140 if feedback from a pressure sensor associated with coring bit 130 indicates that downward pressure applied by ram 170 is no more than a predetermined magnitude. If the downward pressure reaches this predetermined magnitude, ECU 195 causes the drill shaft 120 and coring bit 130 to be retracted by a predetermined distance and / or delays extension of ram 170 for a predetermined time interval.

[0040] During an initial coring phase, which in the illustrated embodiment is associated with a cutting tip of coring bit 130 being at between 0 mm and 10-30 mm depth relative to surface 300, ECU 195 causes ram 170 to extend at a relatively slow rate of between around 1 mm / s and around 10 mm / s, and drill shaft 120 to rotate at the predetermined initial speed indicated in Table 1 above. This facilitates preventing teeth of the coring bit 130 from bending. Once the cutting tip of coring bit 130 has reached a depth of 10-30 mm relative to surface 300, ECU 195 causes stabilisers 180 to retract, if relevant; ram 170 to extend at a relatively faster rate; and drill shaft 120 to rotate at the predetermined operational speed indicated in Table 1 above.

[0041] Once the desired core depth has been achieved, the operator uses the joystick controls to instruct ECU 195 to cause the drill shaft 120 and coring bit 130 to be raised to withdraw the coring bit from the core drilled through surface 300.

[0042] Advantages of at least the embodiment described with reference to FIGS 1 to 3 include: • Increased efficiency in the installation of light bases in pavements, especially pavements subject to significant volumes of traffic, such as airport / airfield pavements; • Reduced risk of damage or injury to coring equipment and its operators; • High precision coring, with a reduction in core edge chipping and hairline fractures of the pavement surface; 2025287264   23 Dec 2025 • Efficient coring, with a target rate of a minimum of 20 “cores” in a shift and penetration depths exceeding 800mm; • Facilitates use of coring bits of up to 600mm in diameter; • Facilitates control of the downward force on the coring bit to enhance coring rate, reduce damage to the pavement surface, and control wear of the bit to increase its service life; • Reduced dust and debris created by coring; • Facilitates relatively straightforward removal of a drilled core; and • A high degree of coring rig mobility.

[0043] It will be appreciated by persons skilled in the art that numerous variations and / or modifications may be made to the above-described embodiments, without departing from the broad general scope of the present disclosure. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive. Examples of possible variations and / or modifications include, but are not limited to: • the longitudinal axis A of the drill shaft 120 being offset from a centre of the base 112 by a distance other than up to 0.3 times the diameter of the largest diameter coring bit that can be used by the assembly 100, such as by a distance of no more than 0.5 times or of no more than 0.8 times the diameter of the largest diameter coring bit that can be used by the assembly 100.

Claims

1. A coring apparatus comprising:a coring assembly, comprising:a stabilising stand having a base for resting on a surface in which a core is to be drilled by the coring apparatus, the base having a length and a width defining a footprint, and a frame fixedly connected relative to and extending upwardly from the base, wherein the width of the base defines a first direction and the length of the base defines a second direction perpendicular to the first direction;at least three anchor points associated with the stand to facilitate connection of the coring assembly to a mobile construction machine, wherein two of the anchor points are spaced apart in the first direction and another of the anchor points is offset from a line drawn between said two anchor points;a rotatable drill shaft adapted to have a coring bit fastened thereto, the drill shaft having a longitudinal axis and being moveable along the longitudinal axis relative to the base, the longitudinal axis extending through the footprint;an input drive for rotating the drill shaft, the input drive being mounted relative to the stand, the input drive comprising a hydraulic motor and associated gearbox; andan actuator for moving the drill shaft along the longitudinal axis relative to the base, the actuator comprising a hydraulic ram;an opening in the base through which a coring bit fastened to the drill shaft passes, in use; anda hydraulic system having a plurality of hydraulic pumps, a first subset of the hydraulic pumps being independent of a second subset of the hydraulic pumps;wherein the first subset of the hydraulic pumps is configured to supply pressurised hydraulic fluid independently to both the input drive and to the hydraulic ram of the coring assembly,wherein the coring apparatus is configured for use with coring bits of up to a maximum predetermined diameter; andwherein the length and width of the base are both at least 1.2 times the maximum predetermined diameter.2025287264   05 Aug 20262.      A coring apparatus according to claim 1, wherein, in terms of axes defined bythe first and second directions, the longitudinal axis of the drill shaft is offset from a centre of the base by a distance of no more than 0.8 times the maximum predetermined diameter, such as by a distance of no more than 0.5 times the maximum predetermined diameter, or by a distance of no more than 0.3 times the maximum predetermined diameter.

3. A coring apparatus according to claim 1 or claim 2, wherein the footprintsubstantially surrounds the coring bit, in use.

4. A coring apparatus according to any one of the preceding claims, wherein alongitudinal axis of the frame and the longitudinal axis of the drill shaft are offset on opposite sides of a centre of the base.

5. A coring apparatus according to any one of the preceding claims, wherein arange of motion of the drill shaft along its longitudinal axis relative to the base comprises a point at which a lower end of the drill shaft is substantially at a level of an underside of the base.

6. A coring apparatus according to claim 5, wherein the range of motioncomprises a point at which the lower end of the drill shaft is below the level of an underside of the base, such as at least 50mm below or at least 100mm below the level of the underside of the base.

7. A coring apparatus according to claim 5 or claim 6, wherein the range ofmotion is at least 500mm long, such as at least 600mm long, or at least 700mm long, or at least 800mm long or at least 900mm long.

8. A coring apparatus according to any one of the preceding claims, wherein thedrill shaft is carried by a carriage that is slidably mounted relative to the frame.2025287264   05 Aug 20269.      A coring apparatus according to claim 8, wherein the actuator extends betweenthe carriage and a point on the frame distal from the base.

10. A coring apparatus according to claim 8 or claim 9, wherein the carriageincludes a platform that extends from the frame in a direction substantially parallel to the base.

11. A coring apparatus according to claim 10, wherein the drill shaft extends fromthe platform at a location offset from the frame in the first direction.

12. A coring apparatus according to any one of the preceding claims, wherein, inuse, the actuator controls a force with which the coring bit is pressed against the surface to be cored.

13. A coring apparatus according to any one of the preceding claims, wherein thegearbox comprises a hydraulic pump drive.

14. A coring apparatus according to any one of the preceding claims, wherein thehydraulic ram has a volume of at least 4000cm3, of at least 5000cm3, of at least 6000cm3, of at least 7000cm3, or of around 8000cm3.

15. A coring apparatus according to any one of the preceding claims, wherein theinput drive facilitates the rotational speed of the drill shaft being set at a rotational speed in at least two ranges selected from the group consisting of: between 100 RPM and 150 RPM; between 150 RPM and 300 RPM; between 300 RPM and 450 RPM; between 450 RPM and 800 RPM; and between 800 RPM and 1600 RPM.

16. A coring apparatus according to any one of the preceding claims, comprising acontroller for controlling operation of the coring assembly, wherein the controller causes the drill shaft to rotate at a first rotational speed until coring has advanced by a predetermined distance and to rotate at a second rotational speed thereafter, the second rotational speed being greater than the first rotational speed.2025287264   05 Aug 202617.     A coring apparatus according to any one of the preceding claims, wherein theinput drive is configured to supply a torque to the drill shaft of up to around 1300 Nm, up to around 1000 Nm or up to around 750 Nm.

18. A coring apparatus according to any one of the preceding claims, wherein theinput drive is configured to vary a torque supplied to the drill shaft between around 50 Nm and around 1300 Nm or between around 80 Nm and around 1000 Nm.

19. A coring apparatus according to any one of the preceding claims, comprising amobile construction machine to which the coring assembly is mounted via the at least three anchor points,the mobile construction machine comprising the first subset of the hydraulic pumps and the second subset of the hydraulic pumps.

20. A coring apparatus according to claim 19, wherein the mobile constructionmachine is a skid steer loader, a multi-terrain loader, or another type of skid steer machine.

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