WORKING MACHINE AND METHOD FOR WORKING THE GROUND

Abstract

The invention relates to a working machine and a method for working the ground with the working machine, having a mast, along which, by means of a positioning means, a rotary head is moved vertically, by which a telescopic Kelly rod having at least two Kelly bars is displaced and guided. According to the invention the Kelly bars are locked or unlocked automatically by means of a control, wherein by means of a first detection means a rotation angle of at least one Kelly bar is detected and/or by means of a second detection means a force, torque or pressure change is detected in a hydraulic system. By the control a locking and/or unlocking of the Kelly bars is determined depending on the detected rotation angle and/or the detected change.

Claims

1. A working machine, in particular construction machine, having a mast, along which, by means of a positioning means, a rotary head is vertically movable, by which a telescopic Kelly rod having at least two Kelly bars is guided in a displaceable manner, wherein an outer Kelly bar designed for being supported on the rotary head and an inner Kelly bar are provided which comprises a rope suspension for a rope, by which the inner Kelly bar is vertically movable by means of a main rope winch, wherein, for the purpose of torque transmission, Kelly bars are provided on their external and/or internal sides with axially running drive keys as well as locking recesses on the drive keys which can be moved into the locking recesses for axially locking the Kelly bars or moved out of the locking recesses for unlocking, wherein a control is provided which is designed for the locking and/or unlocking of the Kelly bars, wherein for the automatic locking of the Kelly bar the control is configured such that a first torque can be applied to the Kelly bar, wherein a latch element is applied with slight pressure to a drive key of the opposite Kelly bar, and the two Kelly bars are moved axially relative to each other until the latch element rotates in the circumferential direction into a locking recess, by means of a first detection means a rotation angle of at least one Kelly bar can be detected during inward rotation or that by means of a second detection means a force, torque or pressure change in a drive system, by which at least the positioning means, the rotary head or the main rope winch are driven, can be detected during inward rotation, and the control is designed to determine the locking of the Kelly bars depending on the detected rotation angle or the detected force, torque or pressure change in the drive system.

2. The working machine according to claim 1, wherein the Kelly rod has one or several intermediate Kelly bars that are arranged between the outer Kelly bar and the inner Kelly bar.

3. The working machine according to claim 1, wherein on a lower end of the inner Kelly bar a ground working tool, in particular a drilling bucket or an auger, is mounted in a releasable manner.

4. The working machine according to claim 1, wherein at least one input means is provided, with which a type and/or size of the Kelly rod, a position of the positioning means for the rotary head, a position of the rope and/or a type and/or size of the rotary head can be entered.

5. The working machine according to claim 1, wherein the first detection means has a rotation angle encoder for detecting a rotation angle.

6. The working machine according to claim 1, wherein the second detection means has a pressure sensor for detecting a pressure increase in a hydraulic drive system.

7. A method for working the ground with a working machine, in particular according to claim 1, having a mast, along which, by means of a positioning means, a rotary head is moved vertically, by which a telescopic Kelly rod having at least two Kelly bars is displaced and guided, wherein an outer Kelly bar that is supported on the rotary head and an inner Kelly bar are provided that is suspended on a rope, by which the inner Kelly bar is moved vertically by means of a main rope winch, wherein, for the purpose of torque transmission, the Kelly bars are provided on their external and/or internal sides with axially running drive keys as well as locking recesses on the drive keys which are moved into the locking recesses for axially locking the Kelly bars or moved out of the locking recesses for unlocking, wherein by means of a control the Kelly bars are locked or unlocked, wherein for the automatic locking of a Kelly bar a first torque is applied thereto, wherein a latch element is applied with slight pressure to a drive key of the opposite Kelly bar, the two Kelly bars are moved axially relative to each other until the latch element rotates in the circumferential direction into a locking recess, by means of a first detection means a rotation angle of at least one Kelly bar is detected during inward rotation or by means of a second detection means a force, torque or pressure change in a drive system, by which at least the positioning means, the rotary head or the main rope winch are driven, is detected during inward rotation, and by the control the locking of the Kelly bars is determined depending on the detected rotation angle or the detected force, torque or pressure change.

8. The method according to claim 7, wherein for the locking and/or unlocking a ground working tool on the Kelly rod is placed onto the ground, in particular onto a borehole bottom.

9. The method according to claim 7, wherein a borehole is produced in the ground.

10. The method according to claim 9, wherein the borehole is filled to form a foundation element.

11. The method according to claim 7, wherein the Kelly bar with the latch element is moved axially relative over a predetermined distance.

Description

[0025] The invention is explained further hereinafter by way of preferred embodiments illustrated schematically in the drawings, wherein show:

[0026] FIG. 1 a schematic partial view of a first working machine according to the invention;

[0027] FIG. 2 a schematic partial view of a second working machine according to the invention;

[0028] FIG. 3 a schematic broken-away illustration of a Kelly rod before unlocking; and

[0029] FIG. 4 a schematic broken-away illustration of the Kelly rod of FIG. 3 after locking.

[0030] The working machine 10 according to FIGS. 1 and 2 has in each case a substantially vertical mast 12 that possesses a mast head 14 each which is only depicted in FIG. 1. Via a rope 52 driven by a main rope winch 50 and guided via deflection rollers 16 on the mast head 14 a Kelly rod 40 is suspended in a vertically displaceable manner along the mast 12.

[0031] According to the two embodiments pursuant to FIGS. 1 and 2 the Kelly rod 40 is in each case designed with an upper-lying outer Kelly bar 42, a lower-lying inner Kelly bar 46 and an intermediate Kelly bar 44 arranged in-between. On the upper end of the inner Kelly bar 46 a rope suspension 48 is provided, on which the rope 52 is designed for the vertical displacement of the inner Kelly bar 46 and of the further tubular Kelly bar elements.

[0032] At its upper end the outer Kelly bar 42 has a supporting collar 43, with which the outer Kelly bar 42 is supported on a rotary head 30, i.e. an annular rotary drive. For the damping of shocks a damping means 32 with springs is arranged between the rotary head 30 and the supporting collar 43 in the embodiment according to FIG. 1. The rotary head 30 and therefore the outer Kelly bar 42 can be moved vertically along the mast 12 via a positioning means 20. In the embodiment according to FIG. 1 the positioning means 20 is designed as a hydraulic cylinder. To transmit the torque from the rotary head 30 to the outer Kelly bar 42 and therefore to the Kelly rod 40 as a whole drive keys 66 are arranged on the outer Kelly bar 42 on the external side thereof, as can be seen in FIG. 2.

[0033] In a known manner, corresponding drive keys 66 or latch elements are also arranged on the other external sides and internal sides of the further Kelly bar elements. On a lower side of the inner Kelly bar 46 a pin-shaped connection element 49 is provided, with which a ground working tool 36 can be mounted in a torque-proof manner. In the embodiments according to FIGS. 1 and 2 the ground working tool 36 is designed as an auger.

[0034] In FIGS. 3 and 4 a simplified Kelly rod 40 with an outer Kelly bar 42 and an inner Kelly bar 46 is illustrated. For the torque transmission from the outer Kelly bar 42 to the inner Kelly bar 46 the outer Kelly bar 42 has on its internal side at least one latch element 62 which rests in the circumferential direction against an axially running drive key 66 on the external side of the inner Kelly bar 46.

[0035] For an axial locking of the outer Kelly bar 42 and the inner Kelly bar 46 the latch element 62 on the outer Kelly bar 42 is pressed lightly against the drive key 66 by applying a slight torque via the rotary head 30 by means of a control according to the invention. In this pressed-on position the outer Kelly bar 42 and the inner Kelly bar 46 are now moved axially to each other either via the positioning means 20 or the main rope winch 50. When the position illustrated in FIG. 4 is reached, the outer Kelly bar 42 with the latch element 62, on reaching a locking recess 68 designed as an axial recess in the drive key 66, rotates counter-clockwise in the circumferential direction into the locking recess 68 in the illustrated embodiment. In doing so, a twisting takes place between the outer Kelly bar 42 and the inner Kelly bar 46 which can be ascertained by a first detection means, in particular a sensor means, as an indication for a locking.

[0036] Upon further axial movement of the outer Kelly bar 42 with respect to the inner Kelly bar 46 the block-like latch element 62 abuts axially against an axial stop 69 of the locking recess 68. A further axial movement of the outer Kelly bar 42 is now no longer possible or only with an increased expenditure of force which can be detected as a pressure increase in the hydraulic system, by which the axial drive member is driven. Likewise, an abutment of the latch element 62 in the circumferential direction against a lateral surface of the locking recess 68 can also be ascertained as a pressure change by means of a second detection means, such as a pressure sensor, in the hydraulic system for driving the rotary head. These respective pressure changes can be detected as a further indication for the presence of a successful locking of the Kelly bars and registered by the control.