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, comprising: a mast, a hydraulic cylinder, a rotary head that is vertically movable by the hydraulic cylinder, a telescopic Kelly rod having at least two Kelly bars configured to be guided in a displaceable manner by the rotary head, the at least two Kelly bars comprising: an outer Kelly bar designed for being supported on the rotary head, and an inner Kelly bar which comprises a rope suspension for a rope, the inner Kelly bar being vertically movable by means of a main rope winch, wherein, each of the at least two Kelly bars include, on their external and/or internal surfaces, axially running drive keys and locking recesses on the drive keys or latch elements configured to move into the locking recesses for axially locking the at least two Kelly bars or moved out of the locking recesses to unlock the at least two Kelly bars in order to transmit torque from the rotary head to a ground working tool, and a drive system, by which at least the hydraulic cylinder, the rotary head or the main rope winch are driven, wherein: a controller is provided which is configured for the locking and/or unlocking of the Kelly bars, the controller is configured such that: a first torque can be applied to one of the at least inner or outer Kelly bars, wherein a latch element is applied with pressure to the axially running drive key of another of the inner and outer Kelly bars, and the at least two Kelly bars are moved axially relative to each other until the latch element rotates in the circumferential direction into a locking recess, the working machine further comprising a detector arranged in the drive system or in the hydraulic cylinder configured to detect a force, torque or pressure change in the drive system indicating rotation of the Kelly bars, and wherein the controller is configured to determine the locking of the Kelly bars depending on the detected force, torque or pressure change in the drive system, and wherein the force, torque or pressure change is indicated by a temporary load drop measured by the detector.

2. The working machine according to claim 1, wherein the Kelly rod comprises at least one intermediate Kelly bar that is arranged between the outer Kelly bar and the inner Kelly bar.

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

4. The working machine according to claim 1, further comprising at least one input configured to enter a type and/or size of the Kelly rod, a position of the hydraulic cylinder for the rotary head, a position of the rope and/or a type and/or size of the rotary head.

5. The working machine according to claim 1, wherein the detector has a pressure sensor for detecting a pressure increase.

6. A method for working the ground with the working machine according to claim 1, wherein the Kelly bars are locked or unlocked by the controller, a first torque is applied to one of the inner and outer Kelly bars, wherein a latch element is applied with pressure to the axially running drive key of another of the inner and outer Kelly bars, the two Kelly bars are moved axially relative to each other until the latch element rotates in the circumferential direction into the locking recess, a force, torque or pressure change in the drive system is detected during rotation, and the locking of the Kelly bars is determined depending on the detected force, torque, or pressure change.

7. The method according to claim 6, wherein the ground working tool on the Kelly rod is placed onto the ground for locking and/or unlocking the Kelly bars.

8. The method according to claim 6, wherein a borehole is produced in the ground.

9. The method according to claim 8, wherein the borehole is filled to form a foundation element.

10. The method according to claim 6, wherein the Kelly bar with the latch element is moved axially relative over a predetermined distance.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is explained further hereinafter by way of preferred embodiments illustrated schematically in the drawings, wherein show:

(2) FIG. 1 a schematic partial view of a first working machine according to the invention;

(3) FIG. 2 a schematic partial view of a second working machine according to the invention;

(4) FIG. 3 a schematic broken-away illustration of a Kelly rod before unlocking; and

(5) FIG. 4 a schematic broken-away illustration of the Kelly rod of FIG. 3 after locking.

DETAILED DESCRIPTION

(6) 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.

(7) 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.

(8) 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.

(9) 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.

(10) 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.

(11) 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.

(12) 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 15, 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, a force change or a torque change by means of a second detection means 25, such as a pressure sensor, a force sensor or a torque sensor, in the hydraulic system 15 for driving the rotary head. These respective pressure, force or torque changes can be detected as a further indication for the presence of a successful locking of the Kelly bars and registered by the control.