Self-propelled drilling head

Abstract

A self-propelled drilling head for drilling in soil by means of a multi-stage method comprises the drilling head having a housing and a drilling head tip arranged in the housing, and a spacer provided on the drilling head tip, by means of which the drilling head tip is in contact with the housing in order to change the multi-stage method to a method with a reduced number of stages.

Claims

1. A self-propelled drilling head for drilling in soil by means of a multi-stage process, comprising: a housing; and a drilling head tip, having an outwardly directed end for contacting the soil during drilling, arranged in the housing; an adapter arranged on the drilling head tip forward of the housing with respect to forward movement of the drilling head; a removable spacer arranged between the housing and the adapter and configured for installation on the drilling head tip to place the drilling head tip in contact with the housing in order to change the multi-stage process to a process with a reduced number of stages; wherein the adapter is removable for insertion and removal of the spacer.

2. The drilling head according to claim 1, wherein the spacer abuts against a front area of the housing.

3. The drilling head according to claim 1, wherein the drilling head tip is prestressed by means of the spacer.

4. The drilling head according to claim 1, wherein the spacer comprises an elastic plastic.

5. The drilling head according to claim 1, wherein the spacer is arranged in a ring around the drilling head tip.

6. The drilling head according to claim 1, wherein the spacer is formed of a plurality of parts.

7. In a self-propelled drilling head designed for underground drilling in soil according to a multi-stage process, the drilling head having a housing and a drilling head tip arranged in the housing, a method comprising: using a spacer in the self-propelled drilling head on the drilling head tip during underground drilling in soil, by means of which the drilling head tip is in contact with the housing in order to use the drilling head in an underground drilling method with a reduced number of stages, wherein, in one of the reduced number of stages, a percussion piston strikes both the drilling head tip and the housing.

8. A method for retrofitting a self-propelled drilling head for drilling underground in soil according to a multi-stage process, the drilling head having a housing and a drilling head tip arranged in the housing, comprising opening the housing and inserting a spacer, closing the housing to cause the spacer to come in contact with the drilling head tip and the housing in order to modify the multi-stage process of underground drilling by reducing the number of stages, wherein, in one of the reduced number of stages, a percussion piston strikes both the drilling head tip and the housing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is explained in more detail below using an exemplary embodiment shown in the figure.

(2) The drawings show:

(3) FIG. 1 illustrates a front portion of a drilling head for drilling in soil in a partially sectioned view;

(4) FIG. 2 illustrates a detailed view of FIG. 1; and

(5) FIG. 3 illustrates the detailed view of FIG. 2 in the retrofitted state.

DETAILED DESCRIPTION

(6) FIG. 1 shows a partially sectioned illustration of a front area of a drilling head 1 for drilling in the soil. The drilling head 1 has a drilling head tip 2 and a housing 3, in which the drilling head tip 2 is arranged. A bearing 6 is provided in the housing 3, in which the drilling head tip is mounted. Basically, the drilling head tip 2 is held in the housing 3 in a longitudinally movable manner along the longitudinal axis marked with L. A compression spring 4 is provided between the housing 3 and the drilling head tip 2, by means of which the drilling head tip 2 is kept at a distance from a stop surface 5 on the housing 3.

(7) The housing 3 is used as a front housing in a housing 7 in which a percussion piston 8 is arranged. The drilling head tip 2 has an exposed end 9 which can come into contact with the ground. At the end 10 opposite the end 9 of the drilling head tip 2 exposed to the soil, an anvil is formed at the end, which can be acted upon by the percussion piston 8.

(8) The illustrated drilling head 1 can be operated in several operating modes, which differ in terms of the stages or timing. In the multi-stage process, the percussion piston 8 hits the anvil of the drilling head tip 2 at the end 10, so that the drilling head tip 2 is first moved until the drilling head tip 2 meets the stop surface 5 of the housing 3 by its stop surface 11 (see also here FIG. 2). Only then is the entire drilling head 1 driven forward by the residual impact energy of the percussion piston 8 via the housing 3. During the backward movement of the percussion piston 8, the drilling head tip 2 is returned to the starting position by the compression spring 4.

(9) In order to change the multi-stage method, a spacer 12 is provided, by means of which the drilling head tip 2 can be brought into contact with the housing 3. While the spacer 12 is not present in the multi-stage process (FIG. 2), the spacer 12 brings about a reduction in the number of stages or the number of cycles. By securing the drilling head tip 2 in the housing 3, the longitudinal mobility of the drilling head tip 2 relative to the housing 3 is reduced and, when the impact piston 8 strikes the end 10 of the drilling head tip 2, the housing 3 is driven forward indirectly via the drilling head tip 2. The spacer 12 holds the compression spring 4 under increased continuous tension and compensates for the play between the stop surface 5 of the housing 3 and the stop surface 11 of the drilling head tip 2. The spacer holds the stop surface 5 of the housing in contact with the stop surface 11 of the drilling head tip 2 (FIG. 3). If the percussion piston 8 thus strikes the end area of the drilling head tip 2 configured as an anvil, the entire impact energy of the percussion piston 8 is transmitted substantially directly via the housing 3 in order to move the entire drilling head 1 forward. By means of the spacer 12, the drilling head 1 shown in FIG. 1 is designed for the one-step process.

(10) In the embodiment shown in FIG. 1, the drilling head tip 2 is arranged in the receiving space 13 of the housing 3, the receiving space 13 having an oversize compared to the circumference of the drilling head tip 2. The drilling head tip 2 is contacted by means of the bearing 6, which ensures the entire mounting of the drilling head tip 2 in the housing 3.

(11) For easy access or a simple retrofitting option of the drilling head 1 shown in FIG. 1, the drilling head 1 has at the front end of the housing 3 an adapter 14 attachable to the housing 3, which is designed in two parts in the illustrated embodiment. The first part 15 of the adapter 14 covers the front area of the housing 3. The first part 15 of the adapter 14 can be fixed or secured on the drilling head tip 2 by means of dowel pins 17. For sealing between the first part 15 of the adapter 14 and the housing 3, an annular circumferential seal 18 is provided in the housing 3, which is arranged in a corresponding groove 19 in the housing 3. A second part 16 of the adapter 14 is also fixed or secured on the drilling head tip 2 by means of dowel pins 17. The second part 16 of the adapter 14 has cutting edges.