Extendable apparatus, drill head and method

Abstract

The present disclosure relates to an extendable apparatus, such as an extendable apparatus for a drill head, a drill head including an extendable apparatus, and a method of operating a drill head. The extendable apparatus includes a base section, a drive section, an extension section, and a functional section. The base section and the drive section are moveable with respect to the extension section and the functional section along a longitudinal axis. The drive section and the functional section are rotationally rigidly coupled to each other. The base section and the extension section are rotationally rigid coupled to each other, and the drive section and the functional section are rotationally moveably coupled to the extension section.

Claims

1. An extendable apparatus for a drill head, comprising: a base section; a drive section; an extension section; and a functional section, the base section and the drive section being moveable with respect to the extension section and the functional section along a longitudinal axis, the drive section and the functional section being rotationally rigid coupled to each other, the base section and the extension section being rotationally rigid coupled to each other, and the drive section and the functional section being rotationally moveably coupled to the extension section, wherein the functional section is arranged to receive a functional drill element for performing a drilling operation.

2. The extendable apparatus according to claim 1, wherein the base section and the drive section are rotationally moveable relative to each other.

3. The extendable apparatus according to claim 1, wherein the extension section and the functional section are rotationally moveable relative to each other.

4. The extendable apparatus according to claim 1, wherein at least one of the extension section and the base section are rotationally rigidly coupled to a housing.

5. The extendable apparatus according to claim 1, wherein at least one of the base section and the extension section include at least one connector for the provision of a supply media.

6. The extendable apparatus according to claim 1, wherein at least one of the functional section and the drive section are rotationally driven by a drive unit about the longitudinal axis.

7. The extendable apparatus according to claim 1, wherein the functional section is coupled to the extension section via a bearing.

8. The extendable apparatus according to claim 7, wherein the bearing is a double row angular ball bearing.

9. The extendable apparatus according to claim 1, wherein an extension volume is disposed between the base section and the extension section, wherein the extendable apparatus is extendable by provision of hydraulic fluid to the extension volume.

10. The extendable apparatus according to claim 1, wherein a retraction volume is disposed between the base section and the extension section, wherein the extendable apparatus is retractable by provision of hydraulic fluid to the retraction volume.

11. The extendable apparatus according to claim 1, wherein at least one torsionally rigid coupling is disposed between the functional section and the drive section for transmitting lateral forces in at least one direction different from a direction parallel to the longitudinal axis.

12. The extendable apparatus according to claim 1, wherein the base section and the drive section are fixed relative to each other with respect to the longitudinal axis.

13. The extendable apparatus according to claim 1, wherein the extension section and the functional section are fixed relative to each other with respect to the longitudinal axis.

14. The extendable apparatus according to claim 1, further comprising a chuck formed as part of the functional section, wherein the chuck forms a central cavity for supplying a fluid to the extension section and/or the functional section.

15. The extendable apparatus according to claim 14, wherein a second sealing kit is arranged between the chuck and the extension section.

16. An extendable apparatus for a drill head comprising: a base section; a drive section; an extension section; a functional section, the base section and the drive section being moveable with respect to the extension section and the functional section along a longitudinal axis, the drive section and the functional section being rotationally rigid coupled to each other, the base section and the extension section being rotationally rigid coupled to each other, and the drive section and the functional section being rotationally moveably coupled to the extension section, wherein the functional section is arranged to connect a functional drill element for performing a drilling operation; and a fluid channel formed as part of the base section, wherein the fluid channel forms a central cavity for supplying a fluid to the extension section and/or the functional section.

17. The extendable apparatus according to claim 16, wherein a first sealing kit is arranged between the fluid channel and the extension section.

18. A drill head, comprising: an extendable apparatus according to claim 1; and a drive unit arranged for rotationally driving at least one of the drive section and the functional section of the extendable apparatus about the longitudinal axis.

19. A method of operating a drill head, comprising the steps of: providing a drill head according to claim 18; connecting a functional drill element to the functional section; rotating the functional section of the extendable apparatus by rotationally driving the drive section of the extendable apparatus; and extending and/or retracting the extendable apparatus along the longitudinal axis.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIGS. 1a and 1b: show a longitudinal cross-sectional, lateral view of a drill head with an extendable apparatus in the retracted position and extended position;

(2) FIGS. 2a and 2b: show a longitudinal cross-sectional, plan view of the drill head of FIG. 1 with and without the functional drill element;

(3) FIG. 3: shows a side view of the drill head from the opposite perspective as shown in FIG. 2;

(4) FIG. 4: shows a cross-sectional, plan view of a drill head cut in the area of the spur gear reduction;

(5) FIG. 5: shows a front view of the drill head;

(6) FIG. 6: shows an enlarged view of FIG. 1 in the area of the fluid channel;

(7) FIG. 7: shows a cross-sectional, view of the drill head cut in the area of the distal end; and

(8) FIG. 8: shows a first three-dimensional depiction of the drill head.

DETAILED DESCRIPTION

(9) In FIGS. 1-8 a preferred example of a drill head 5000 with an extendable apparatus 50 with a drive unit 5100 is shown. Although in the figures the extendable apparatus 50 is shown in the retracted position in FIG. 1a, the extendable apparatus 50 can be extended along its longitudinal axis LA by a translational movement of the second translational unit 600 comprising the extension unit 650 and the functional section 660 relative to the first translational unit 500 comprising the base section 550 and the drive section 560 as shown in FIG. 1b. The drive section 560 and the functional section 660 are rotationally rigid coupled to each other, as well as the base section 550 and the extension section 650 are rotationally rigid coupled to each other. The drive section 560 and the functional section 660 are rotationally movable coupled to the extension section 650. Functional drill element DE is connectable to functional section 660 as shown in FIG. 2b.

(10) Further, the base section and the drive section are rotationally movable relative to each other and fixed relative to each other with respect to the longitudinal axis LA. Similarly, the extension section 650 and the functional section 660 are rotationally movable relative to each other and fixed relative to each other with respect to the longitudinal axis LA. Both, the extension section 650 and the base section 550 are rotationally rigid coupled to a housing. The functional section 660 and the drive section 560 are adapted for being rotationally driven by the drive unit 5100 about the longitudinal axis LA. Drive unit 5100 is adapted to drive the drive section 560 via the spur gear reduction stage 5300, which transfers the torque to the drive section. The extendable apparatus 50 is supported by taper roller bearings 5400 arranged back to back. The two rings of taper roller bearings 5400 are adapted to receive the loads and forces coming from operation of the drill head 5000. Next to the taper roller bearings 5400, V-rings 702 are located. On the distal side, these are arranged as double-V-rings. These rotational seals or V-rings 702 need to have a compact desing based on the limited space available. Speed sensors 5700 are adapted to control the speed of the rotation.

(11) The drive section 560 has a substantially shaft-formed structure enclosing the functional section 660. The functional section 660 has a substantially shaft-formed structure enclosing the extension section 650. Further, the functional section 660 comprises a protrusion or spline coupling 622 at its proximal end, wherein the protrusion or spline coupling 622 is rotationally rigid coupled with the drive section 560 and longitudinally or translationally moveable relative to the drive section 560. Further, at least one torsionally rigid coupling 60 is located between the functional section 660 and the drive section 560 for transmitting lateral forces in at least one direction, different from a direction parallel to the longitudinal axis LA. Additional side forces can be supported by the spline coupling 622 and/or by the transmission element 530 in the form of the slide bearing between the functional section 660 and the drive section 560. The base section 550 is sealed against the extension section 650 via first and second main sealing kits 700, 701. The extension section 650 comprises a double-wall with an inner wall 610 and an outer wall 620. At the proximal end 621 of the outer wall, a sealing sleeve 623 is located.

(12) Connectors for the provision of hydraulic fluid in the form of hydraulic fluid supply 800 are realized at the base section 550, namely in the form of a radial hydraulic fluid supply 810 and a longitudinal hydraulic fluid supply 820, which feed first and second hydraulic fluid channels 830, 840 to supply pressurized hydraulic fluid to the extension volume 850 between the base section 550 and the extension section 650 and to the retraction volume 860 between the base section 550 and the extension section 650. The extendable apparatus 50 is extendable by provision of hydraulic fluid to the extension volume 850 and it is retractable by provision of hydraulic fluid to the retraction volume 860. Space 880 is connected to a breather in order to allow for the extendable apparatus to be extended and retracted. The complete functions of the extendable apparatus 50 are hydraulically secured against overloads or excess pressure by a pressure valve 870.

(13) A fluid channel 540 is part of the base section 550 and a chuck 900 is part of the functional section 660. Together, the fluid channel 540 and the chuck 900 form a central cavity 541 or central chamber for supplying a fluid, in particular water or air, to the extension section 650 and in particular to the functional section 660, particularly the distal end of the function section 660. A first sealing kit 710 is arranged between the fluid channel 540 and the extension section 650 and is adapted for translational movement or sealing. A second sealing kit 720 is arranged between the chuck 900 and the extension section 650 and is adapted for rotational movement or sealing. As can be seen in particular from FIG. 6, both sealing kits 710, 720 are realized identical or exchangeable with first water seals 750, second water seals 760 and first and second water sealing sleeves 730, 740. At the proximal end of the chuck 900 as well as at the distal end of the fluid channel 540, nuts 703 are located.

(14) The functional section 660 is coupled to the extension section 650 via a double row angular ball bearing 5200, which is positioned between an inner bearing sleeve 910, a holding sleeve 920, a first bearing housing 930 and a second bearing housing 940.