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 power rotary head is moved vertically, by which a telescopic Kelly rod having at least two Kelly bars is displaced and guided, 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 and/or axial latch elements which are moved into the locking recesses for axially locking the Kelly bars or moved out of the locking recesses for unlocking. According to the invention provision is made in that by means of a control a locking state of the Kelly bars is checked automatically, wherein by the control the positioning means of the power rotary head and/or the main rope winch are actuated so that the Kelly bars are moved axially relative to each other, in that by means of a detection means a movement distance of the Kelly bars with respect to each other and/or an axial force during movement of the Kelly bars are axially detected, and in that depending on the detected movement distance and/or the detected axial force a locking state of the Kelly bars is ascertained by the control.

Claims

1. Working machine, in particular construction machine, having a mast, along which, by means of a positioning means, a power 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 power 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, 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 and/or axial latch elements which can be moved into the locking recesses for axially locking the Kelly bars or moved out of the locking recesses for unlocking, characterized in that a control is provided which is designed for automatically checking a correct locking state of the Kelly bars, irrespective of whether a locking process is carried out, wherein by the control the positioning means of the power rotary head and/or the main rope winch can be actuated so that the Kelly bars are moved axially relative to each other, in that at least one detection means is provided, with which a movement distance of the Kelly bars with respect to each other and/or an axial force during movement of the Kelly bars can be detected, and in that depending on the detected movement distance and/or the detected axial force the control is designed to ascertain the correct locking state of the Kelly bars.

2. Working machine according to claim 1, characterized in that in the control a limit value for a maximum movement distance and/or a limit value for a minimum axial pressure are stored and in that in order to determine the correct locking state the detected movement distance can be compared with the maximum movement distance or the detected axial pressure can be compared with the minimum axial pressure.

3. Working machine according to claim 1, characterized in that the Kelly rod has one or several intermediate Kelly bars which are arranged between the outer Kelly bar and the inner Kelly bar.

4. Working machine according to claim 1, characterized in that 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.

5. Working machine according to claims 1, characterized in that during movement of the Kelly bars the power rotary head can be actuated by the control, wherein a predetermined torque can be exerted.

6. Working machine according to claim 1, characterized in that in order to detect the axial force a pressure increase in a hydraulic drive system can be detected.

7. Working machine according to claim 1, characterized in that at least one input and/or determining means is provided, with which a type and/or size of the Kelly rod, a position of the positioning means for the power rotary head and/or a position of the rope can be input or determined.

8. Working machine according to claim 7, characterized in that when detecting the correct locking state the position of the positioning means and/or a position of the rope can be saved in the control means.

9. 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 power 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 power 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 and/or axial latch elements which are moved into the locking recesses for axially locking the Kelly bars or moved out of the locking recesses for unlocking, characterized in that by means of a control a correct locking state of the Kelly bars is checked automatically, irrespective of whether a locking process is carried out, wherein by the control the positioning means of the power rotary head and/or the main rope winch are actuated so that the Kelly bars are moved axially relative to each other, in that by means of at least one detection means a movement distance of the Kelly bars with respect to each other and/or an axial force during movement of the Kelly bars are detected, and in that depending on the detected movement distance and/or the detected axial force the correct locking state of the Kelly bars is ascertained by the control.

10. Method according to claim 9, characterized in that for the purpose of checking, a ground working tool on the Kelly rod is placed onto the ground.

11. Method according to claim 9, characterized in that a borehole is produced in the ground.

12. Method according to claim 11, characterized in that the borehole is filled to form a foundation element.

13. Method according to claim 9, characterized in that by the control an automatic locking process is carried out if no correct locking state has been ascertained.

Description

[0031] The invention is explained further hereinafter by way of preferred embodiments illustrated schematically in the drawings, wherein show:

[0032] FIG. 1 a schematic partial view of a first working machine according to the invention;

[0033] FIG. 2 a schematic partial view of a second working machine according to the invention;

[0034] FIG. 3 a schematic broken-away illustration of a Kelly rod before unlocking; and

[0035] FIG. 4 a schematic broken-away illustration of the Kelly rod of FIG. 3 after locking.

[0036] 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.

[0037] 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 vertically displacing the inner Kelly bar 46 and also the further tubular Kelly bar elements.

[0038] 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 power rotary head 30, i.e. an annular rotary drive. For the damping of shocks a damping means 32 with springs is arranged between the power rotary head 30 and the supporting collar 43 in the embodiment according to FIG. 1. The power rotary head 30 on a carriage 18, and thus 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 power 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.

[0039] 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.

[0040] In FIGS. 3 and 4 a simple Kelly rod 40 having 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.

[0041] 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 can be pressed lightly against the drive key 66 by applying a slight torque via the power rotary head 30 by means of a control. In this pressed-on position the outer Kelly bar 42 and the inner Kelly bar 46 can now be moved axially with respect to each other either via the positioning means 20 or the main rope winch 50 or by both. 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 rotation takes place between the outer Kelly bar 42 and the inner Kelly bar 46 which can be established by a first detection means, in particular a sensor means, as an indication for a locking.

[0042] According to the invention a correct locking state can be checked automatically by the control at any time. To this end, the positioning means 20 and/or the main rope winch 50 with the rope 52 are actuated via the control in such a way that a defined axial movement of the outer Kelly bar 42 with respect to the inner Kelly bar 46 takes place. If a correct locking is present, at least after a certain axial maximum movement distance that usually amounts to a few centimeters for each locking position and in any case does not exceed the axial length of a locking recess, the block-like latch element 62 has to abut 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. Moreover, this leads to 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. This can be detected by the control which then displays that a correct locking is still present.

[0043] If, during the checking process by the control, the axial maximum movement distance is exceeded and/or if no increase of the axial force above a predetermined minimum axial force value is established, a reliable locking is no longer present. This state of the absence of locking can be displayed by the control to the operator of the drilling apparatus. The control can be actuated at any time by the operator of the drilling apparatus so that he is always reliably informed about the correct locking state. If no locking is established, an automatic locking process can preferably be carried out by the control.