Rotary drive arrangement for a drill rod

Abstract

The invention relates to a rotary drive arrangement for a drill rod having an outer pipe and an inner rod running at least in sections inside the outer pipe, in particular for double-head and/or overburden drilling, with a first gearbox for driving the inner rod in a rotating manner and a second gearbox for driving the outer pipe in a rotating manner, wherein the first gearbox and the second gearbox are independent of each other. According to the invention provision is made in that the first gearbox and the second gearbox are supported in a common gearbox housing and are surrounded by the same.

Claims

1. A rotary drive arrangement for a drill rod having an outer pipe and an inner rod running at least in sections inside the outer pipe, in particular for double-head and/or overburden drilling, with a first gearbox for driving the inner rod in a rotating manner and a second gearbox for driving the outer pipe in a rotating manner, wherein the first gearbox and the second gearbox are independent of each other, wherein the first gearbox and the second gearbox are supported in a common gearbox housing and are surrounded by the same, and on an external side of the gearbox housing a displacement means is arranged which is connected in an axially fixed but rotatable manner to the inner rod for axial displacement of the inner rod relative to the gearbox housing.

2. The rotary drive arrangement according to claim 1, wherein the gearbox housing has a center support which runs approximately perpendicularly to the drilling axis and divides the gearbox housing into a first gearbox compartment which faces away from a drilling tool side and a second gearbox compartment which faces towards the drilling tool side.

3. The rotary drive arrangement according to claim 2, wherein the center support has a passage for the inner rod.

4. Rotary drive arrangement according to claim 2, wherein the first gearbox for driving the inner rod is arranged in the first gearbox compartment and the second gearbox for driving the outer pipe is arranged in the second gearbox compartment.

5. The rotary drive arrangement according to claim 1, wherein the gearbox housing has at least one first inlet opening for at least one first drive shaft of at least one first rotary drive and at least one second inlet opening for at least one second drive shaft of at least one second rotary drive.

6. The rotary drive arrangement according to claim 5, wherein the at least one first inlet opening is located on one side of the center support and the at least one second inlet opening is designed on an opposite side of the center support in the gearbox housing.

7. The rotary drive arrangement according to claim 5, comprising a base plate on which the gearbox housing, the at least one first rotary drive, and the at least one second rotary drive are arranged.

8. The rotary drive arrangement according to claim 1, wherein the first gearbox has a first spur gearwheel and/or the second gearbox has a second spur gearwheel which are each rotatably supported in the gearbox housing.

9. The rotary drive arrangement according to claim 8, wherein on the first spur gearwheel a first output element is arranged for driving the inner rod, the said first output element being connected in a torque-proof but axially displaceable manner to the inner rod.

10. The rotary drive arrangement according to claim 8, wherein on the second spur gearwheel a second output element is mounted for driving the outer pipe, on which second output element the outer pipe can be mounted in a torque-proof manner.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The invention is explained in greater detail hereinafter by way of a preferred exemplary embodiment illustrated in the accompanying FIGURE. The FIGURE shows a schematic cross-sectional view through a rotary drive arrangement according to the invention.

DETAILED DESCRIPTION

(2) The illustrated rotary drive arrangement 10 serves to drive a non-depicted double drill rod about a drilling axis 5, with only a part of the inner rod 12 being illustrated. On the inner rod 12 further inner rod elements can be releasably mounted via a connecting section 14 towards a drilling tool side. On a connecting element 56 of the rotary drive arrangement 10 a non-depicted outer pipe can be releasably attached in a manner coaxial with respect to the drilling axis 5.

(3) The rotary drive arrangement 10 comprises a gearbox housing 20 with a center support 22 which is designed along a center plane 21 located orthogonally to the drilling axis 5. The center support 22 is firmly connected to a base plate 26, with which the rotary drive arrangement 10 can be fixed e.g. on a non-depicted drill drive carriage of a drilling apparatus.

(4) On the center support 22 a circumferential wall section 24 running on both sides is designed, on which, towards a rear side facing away from the drilling tool, a first side cover 25 is attached, whereby a first gearbox compartment 31 with a first gearbox 40 for driving the inner rod 12 is encased. On the opposite side of the center support 22 a second side cover 28 is mounted on the circumferential wall section 24, by which second side cover a second gearbox compartment 32 with a second gearbox 50 for driving the outer pipe is encased. The center support 22 has a centrally arranged passage 30, through which the inner rod 12 protrudes from the drilling tool side through the center support 22 towards a rear side.

(5) To drive the inner rod 12 a non-depicted first rotary drive with a first drive shaft 48 is arranged on the base plate 26, the said first drive shaft protruding through a first inlet opening 35 into the gearbox housing 20. On the first drive shaft 48 a first pinion 49 is designed which is in meshing connection with a first externally toothed spur gearwheel 42 of the first gearbox 40. On a side of the first spur gearwheel 42 facing away from the center support 22 a sleeve-shaped first output element 44 is mounted. On its internal side the sleeve-shaped first output element 44 has an internal toothing 45 which engages with an external toothing 16 on the inner rod 12. The external toothing 16 is of greater axial length than the internal toothing 45, thereby providing a torque-proof connection concomitant with axial displaceability of the inner rod 12 with respect to the first gearbox 40.

(6) For axial displacement of the inner rod 12 a displacement means 60 is arranged on a sleeve-like housing shoulder 27 which follows the first side cover 25 and is fixed thereon. The said displacement means has a fixing element 62 which is firmly mounted on the external side of the housing shoulder 27. In addition, a sleeve-shaped carriage 64 is provided which is connected via a rotary bearing 66 in an axially fixed but rotatable manner to the inner rod 12. Via a non-depicted lifting cylinder the carriage 64, and therefore the inner rod 12, can be adjusted relatively axially with respect to the fixing element 62 and therefore with respect to the gearbox housing 20, in which case a bar-shaped linear guide 68 is arranged as anti-twist protection.

(7) Moreover, the inner rod 12 can be of pipe-shaped design, wherein via a generally known rotary feedthrough at the rear end of the inner rod 12 a fluid, in particular concrete slurry, can be fed to the drilling tool side.

(8) On the opposite side of the center support 22 the second gearbox 50 for driving the non-depicted outer pipe is arranged. For this a non-depicted second rotary drive with a second drive shaft 58 is arranged on the base plate 26. The second drive shaft 58 protrudes through a second inlet opening 36 into the gearbox housing 20. Via a second pinion 59 on the second drive shaft 58 a torque can be transmitted to a second spur gearwheel 52 of the second gearbox 50. On a side of the second spur gearwheel 52 facing away from the center support 22 a sleeve-shaped second output element 54 is mounted, on which, for the purpose of mounting the outer pipe of the double drill rod, a Cardanic connecting element 56 is mounted in a torque-proof manner via a transfer ring 55.

(9) The inner rod 12 protrudes through the second output element 54. The respective ring-shaped gaps on the housing passages are sealed off by appropriate ring sealings in order to close the gearbox housing 20 in an oil-tight manner.

(10) By way of the invention two from one another separate gearboxes 40, 50 are arranged in one gearbox housing 20 and are encased by the same in an oil-tight manner. As a result, an altogether compact rotary drive arrangement 10 is achieved.