Ground drilling device, method for making a ground drilling device, method for maintaining a ground drilling device, and use of a ground drilling device

Abstract

A ground drilling device comprising a housing, a lengthwise movable drilling head tip arranged in the housing, and a bearing for supporting the drilling head tip in the housing during its lengthwise movement.

Claims

1. Ground drilling device, comprising a housing, a lengthwise movable drilling head tip arranged in the housing, and a bearing arranged within a receiving space comprising a recess on an inside surface of the housing and open at a front end of the housing, the bearing configured for supporting the drilling head tip in the housing during its lengthwise movement.

2. Device according to claim 1, wherein the receiving space is configured to receive the bearing for the drilling head tip and is accessible at the drilling head end.

3. Device according to claim 2, wherein the receiving space has an extension in the lengthwise direction of the housing in the range of 10 mm to 100 mm.

4. Device according to claim 3, wherein the extension of the receiving space in the lengthwise direction of the housing in relation to an extension of the bearing in the lengthwise direction is a ratio in the range of 1.05 to 1.5.

5. Device according to claim 1, wherein the device is a percussion drilling device.

6. Device according to claim 1, wherein the bearing encloses the drilling head tip at least for a portion on a circumference of the drilling head tip.

7. Device according to claim 1, wherein the bearing comprises multiple segments.

8. Device according to claim 1, wherein the bearing comprises a material which is different from the drilling head tip.

9. Device according to claim 1, wherein an internal diameter of the housing outside the bearing is oversized in relation to the external diameter of the drilling head tip.

10. Device according to claim 1, wherein the bearing is held in the recess of the housing by means of a press-fit or a glued press-fit.

11. Device according to claim 1, wherein the receiving space has an extension in the lengthwise direction of the housing greater than an extension of the bearing in the lengthwise direction, and wherein a portion of the receiving space beyond the bearing is accessible from a side of the housing.

12. Device according to claim 1, wherein a flange on the drilling head tip and an end of the housing are arranged rearward of the receiving space to retain the drilling head tip in the housing.

13. Method for making a ground drilling device, comprising the steps of: providing a housing comprising a receiving space comprising a recess on an inside surface of the housing and open at a front end of the housing, providing a lengthwise movable drilling head tip in the housing and arranging the drilling head tip in the housing, and arranging a bearing for the drilling head tip within the receiving space of the housing between the housing and the drilling head tip for supporting the drilling head tip in lengthwise movement while the drilling head tip is arranged in the housing.

14. The method of claim 13, wherein the receiving space has an extension in the lengthwise direction of the housing greater than an extension of the bearing in the lengthwise direction, and wherein a portion of the receiving space beyond the bearing is configured to be accessed from a side of the housing while the drilling head tip is installed in the housing.

15. The method of claim 13, further comprising arranging a flange on the drilling head tip and an end of the housing rearward of the receiving space to retain the drilling head tip in the housing.

16. Method for maintaining a ground drilling device, comprising the steps of: providing a housing comprising a receiving space comprising a recess on an inside surface of the housing and open at a front end of the housing with a lengthwise movable drilling head tip in the housing, grasping a bearing which is arranged within the receiving space of the housing for supporting the lengthwise movement of the drilling head tip, and pulling the bearing out while the drilling head tip is arranged in the housing.

17. The method of claim 16, wherein the receiving space has an extension in the lengthwise direction of the housing greater than an extension of the bearing in the lengthwise direction, and wherein pulling out the bearing comprises accessing a portion of the receiving space beyond the bearing from a side of the housing to pull out the bearing.

18. The method of claim 16, wherein providing the housing further comprises providing the housing such that a flange on the drilling head tip and an end of the housing are arranged rearward of the receiving space to retain the drilling head tip in the housing during maintenance of the bearing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The drawing shows:

(2) FIG. 1 a region of a ground drilling device at the drilling head end.

DETAILED DESCRIPTION OF THE INVENTION

(3) FIG. 1 shows a section of a ground drilling device at the drilling head end. A drilling head tip 1 is present, which is arranged in a housing 2. For the supporting of the drilling head tip 1, a receiving space 3 is formed in the housing 2 at the end side. The receiving space 3 is accessible from the drilling head end, i.e., from the front. In the receiving space 3 there is arranged a bearing 4. The receiving space 3 with the bearing 4 is covered at the front end by means of an adapter 5 secured to the drilling head tip 1. Moreover, another lengthwise axially movable adapter 6 is provided, which is likewise connected to the drilling head tip 1. If the adapters 5 and 6 are removed, access can be gained to the bearing 4 in the receiving space 3 without having to dismantle the drilling head tip 1. An annular seal 25, arranged in a corresponding groove, is provided for the sealing between adapter 5 and housing 2.

(4) The housing 2 is connected to a housing 7 in which a main piston 10 is arranged. The drilling head tip 1 has an exposed end, which comes into contact with the soil. At the end opposite the end of the drilling head tip 1 exposed to the soil there is formed an anvil 8, which can be struck by the main piston 10.

(5) An annular spring 9 is provided for pretensioning the drilling head tip 1 relative to the housing 2, being arranged between the drilling head tip 1 and the housing 2.