Clamping head arrangement

Abstract

The invention relates to a clamping head arrangement, in particular for clamping a drill rod element, having: a plurality of clamping jaw elements, each of which has a clamping surface, which is designed in particular for clamping contact with a contact side of the drill rod element; and a body having a guide rail along which the gripper jaw element is displaceably mounted, where the guide rail is angled relative to a central axis of the gripper head arrangement such that displacement of the gripper jaw element along the guide rail results in axial and radial displacement of the gripper jaw element relative to the central axis. According to the invention, the gripper jaw elements are each designed with a cylindrical or partially cylindrical guide body, and the guide tracks in the main body are formed as partially cylindrical guide channels, in each of which a gripper jaw element with a cylindrical or partially cylindrical guide body is displaceably mounted.

Description

TECHNICAL FIELD

[0001] The invention relates to a clamping head arrangement, in particular for clamping a drill rod element, having a plurality of clamping jaw elements, each of which has a clamping surface which is designed in particular for clamping contact with a contact side of the drill rod element, and a main body having a guide track along which the clamping jaw elements are mounted displaceably, wherein the guide track is angled with respect to a central axis of the clamping head arrangement such that a displacement of the clamping jaw elements along the guide track results in an axial and radial displacement of the clamping jaw elements with respect to the central axis, according to the preamble of claim 1. BACKGROUND

[0002] Such clamping head arrangements are known, for example, from EP 4 339 417 A1. Further clamping head arrangements are disclosed in US 7,775,270 B1. These clamping head arrangements are used to releasably clamp cylindrical or tubular drill rod elements in order to be able to transmit a drilling torque from a rotary drilling drive. During operation, a drilling tool is attached to a distal end of a drill string, which is formed by one or more drill rod elements by means of which soil material can be removed or displaced, for example, during pile drilling.

[0003] In these clamping head arrangements, the individual clamping jaw elements are mounted for linear displacement in or on the guide track along the main body. The guide track is designed to be centered with respect to the central axis and has a certain angle of attack. This means that the clamping jaw elements can also be adjusted radially during axial displacement in order to clamp or release the drill rod element.

[0004] The clamping jaw elements must be able to be displaced along these guide tracks and at the same time remain in place so that they do not fall out of the guide track when the clamped drill rod element is removed.

[0005] In this regard, the guide tracks are usually designed with an undercut and can be produced, in particular, as a dovetail guide, a T-shaped guide or a similar guide with an undercut. These guides do indeed enable good guidance and reliable fixing of the clamping jaw elements on the main body. However, these guides are sensitive to dirt and damage and are expensive to manufacture. Guide tracks with an undercut, such as dovetail guides, usually require special and thus expensive mold tools for production. Subsequently, hardening and fine machining, for example by means of complex grinding or honing, is still required in order to ensure the precise formation of the guide surfaces. Specialized grinding or honing tools must be used to match the undercut guide track. This results in correspondingly high manufacturing costs for such clamping head arrangements. This also applies in a similar manner to the manufacture of the associated clamping jaw elements, which must be designed to match the undercut guide track. SUMMARY

[0006] This invention addresses the objective of providing a clamping head arrangement with a particularly simple and robust structure.

[0007] According to the invention, this objective is achieved by a clamping head arrangement having the features of claim 1. Preferred embodiments of the invention are specified in the dependent claims.

[0008] The clamping head arrangement according to the invention is characterized in that each clamping claw element is designed with a cylindrical or partially cylindrical guide body, and the guide track in the main body is designed as a partially cylindrical guide channel, in each of the guide channels, a clamping claw element having a cylindrical or partially cylindrical guide body is movable.

[0009] The first aspect of this invention lies in abandoning the complex guide rail with an undercut flat guide surface, and instead forming the guide rail in the body as a partially cylindrical guide channel. The cylindrical channel can be created relatively easily using conventional drilling tools, which is relatively simple in terms of manufacturing technology. After any necessary hardening, the partially cylindrical guide surface can also be smoothly finished very precisely and efficiently using correspondingly cylindrical grinding or reaming tools. In the sense of this invention, the partially cylindrical guide channel should be understood as a cylindrical recess or hole partially open along the axial direction, such that the originally existing guide wall is formed symmetrically with respect to the center or channel axis, thus forming an open guide channel. In this context, the partially cylindrical channel or guide wall extends within an angle range greater than 180°, preferably between 240° and 300°, thereby ensuring a certain undercut construction. The remaining angle range is open.

[0010] Another aspect of the invention is that the gripping claw element is formed with a cylindrical or partially cylindrical guide body corresponding to a partially cylindrical guide channel. For this purpose, the guide body can form a type of guide bar along the actual gripping claw element, or preferably, the gripping claw element itself can be realized by a cylindrical body having a gripping surface formed thereto or attached thereto. This means that such gripping claw elements with cylindrical or partially cylindrical guide bodies can also be manufactured relatively easily, for example using a conventional lathe or turning machine.

[0011] The inner diameter of the guide channel of the gripper element and the outer diameter of the guide body are designed to match each other and preferably form a very fine clearance fit, so that the corresponding gripper element is precisely and reliably guided along the associated guide channel and installed so that it can be displaced.

[0012] A preferred embodiment of the invention features a partially cylindrical guide channel that is open on the side facing the drill pipe element to be clamped. This ensures good and secure guidance of the clamping jaw element within the guide channel, as well as stable and reliable transmission of even high clamping forces.

[0013] A particularly advantageous configuration of the clamping head arrangement according to the invention can be achieved because the body is constructed in annular shape, having a free interior for receiving drill pipe elements, and the guide channel is open inward. Therefore, such a clamping head arrangement with an annular body can be designed to clamp cylindrical drill pipe elements on the outer side. The free interior space in the annular body thus has a diameter larger than the maximum diameter of the drill pipe element to be clamped.

[0014] The drill pipe element can be housed inside and clamped by moving the clamping claw element along the guide track from a radially outward release position to a radially inward clamping position, in which the clamping claw element is pressed against the outside of the drill pipe element and the drill pipe element is thus held at least in a frictional engagement manner.

[0015] To clamp the tubular drill pipe element on its inner side, the clamping head arrangement according to the invention can alternatively be further developed into a type where the main body is designed as a shaft or block with an outer circumferential side, in which a partially cylindrical guide channel with clamping claw elements is arranged, wherein the tubular drill pipe element can be clamped on its inner side. Here, the outer diameter of the shaft-like or block-like main body is smaller than the inner diameter of the tubular free space of the drill pipe element to be clamped.

[0016] Therefore, the axial or block-shaped body can be pushed relative to the tubular interior of the drill pipe element. By moving the clamping jaw element along the guide channel, the clamping jaw element can be moved from a radially inward release position to a radially outward clamping position. In the clamping position, the clamping jaw element can be pressed against the inner side of the tubular drill pipe element. In this way, the tubular drill pipe element can be clamped and held on its inner side at least in a frictional engagement manner, such that, for example, torque can be transmitted to the tubular drill pipe element.

[0017] According to another embodiment of the gripper head arrangement, preferably, the gripper claw elements are connected to at least one actuator, which is mounted to be adjustable relative to the body for displacing the gripper claw elements. Specifically, the actuator may be designed as an annular shape for an external chuck or a disc or block shape for an internal chuck. The actuator is rigidly or preferably connected to the respective gripper claw elements with a certain amount of clearance. By moving the actuator, the respective gripper claw elements move together along guide tracks so as to perform gripping or releasing movements individually.

[0018] In principle, the actuator can be adjusted in any suitable manner using appropriate means. According to a further development of the invention, it is particularly advantageous that the at least one actuator can be axially displaced by means of at least one actuating cylinder, particularly a hydraulic cylinder. Particularly preferably, two or more actuating cylinders are arranged, distributed as evenly as possible along the periphery of the actuator. Thus, the actuator can be adjusted or displaced relative to the body, preferably in the axial direction. The actuating force applied in this process is transmitted to the respective gripping jaw elements in the form of a wedge-shaped sliding mechanism via guide rails angled towards the central axis, with corresponding clamping or releasing forces.

[0019] According to a further development of the invention, preferably, each gripper element is connected to the actuator with a clearance via a connecting device. Specifically, the connecting device is designed such that the gripper element can be axially displaced relative to the actuator. Here, a certain amount of clearance is provided in the radial and / or axial directions, i.e., a certain degree of freedom of movement of the corresponding connected gripper element relative to the actuator. This means that when the gripper element is adjusted, some relative movement between the actuator and the corresponding gripper element can be compensated by means of the corresponding connecting device.

[0020] A contact surface can be formed on the corresponding gripping claw element of the contact member, which is mounted on the gripping claw element with a certain amount of clearance. In this way, minor misalignments can be compensated for, and safe and secure gripping can be achieved.

[0021] According to a further development of the invention, it is particularly advantageous that hook arrangements are formed on the rear region of each gripper element to form a connecting device and engage in an associated receiving mount on the actuator. The hook arrangements can be particularly formed by the fact that groove-like recesses are formed in the lateral direction in the preferably cylindrical gripper elements. The receiving mount on the actuator can be particularly designed as a bracket or a corresponding recess in the actuator.

[0022] Specifically, the hook arrangement can be formed as a single piece with the gripper element, or as a separate hook element attached to the gripper element. Correspondingly, the receiving mount can be formed as a single piece or as a separate component attached to the actuator. In principle, the connecting device can be formed in any suitable manner, wherein, conversely, the hook arrangement can also be formed on the actuator, and the receiving mount can be formed on the corresponding gripper element.

[0023] According to one embodiment of the invention, it is particularly suitable that the clamping jaw arrangement for forming the drill drive arrangement, especially on the drill drive carriage, can be rotatably driven via at least one rotary drive. Therefore, the clamping jaw arrangement can be used to transmit drilling torque from one or more rotary drives to the drill pipe element. In particular, the drill drive arrangement can be used for drilling in soil or rock in civil engineering or mining, where relatively high torque is reliably transmitted to the drill pipe element.

[0024] Specifically, a drill drive arrangement with a clamping head arrangement can be arranged on a drill drive carriage having a carriage body. The carriage body here has a clamping head arrangement, which has at least one rotary drive on one side and a linear guide device can be formed on the other side, using which the drill drive carriage can be guided, for example, along a guide or drill mount.

[0025] The invention also includes a drilling apparatus for creating boreholes, particularly in soil, having at least one drill rod element, wherein a clamping head arrangement according to the invention is provided. In particular, the drilling apparatus may be designed with a chassis, especially a tracked chassis. The drilling apparatus may also have a mast or mounting, which preferably has a linear guide for guiding a drill drive carriage with the clamping head arrangement and at least one rotary drive. The mast or mounting may be capable of being displaced. Attached Figure Description

[0026] The invention will be further described below with reference to preferred exemplary embodiments schematically illustrated in the accompanying drawings, wherein:

[0027] Figure 1 A perspective view of an annular body having gripping claw elements for gripping head arrangement according to the invention is shown from the rear.

[0028] Figure 2 Shown from the front Figure 1 A perspective view of the annular body of the gripper element; and

[0029] Figure 3 A perspective view showing the arrangement of the clamping heads according to the present invention is shown. Detailed Implementation

[0030] according to Figure 1 and Figure 2 The body 12 for the gripper head arrangement 10 according to the invention may be formed as an annular shape with an interior 13 in which cylindrical or tubular rod elements (not shown) can be accommodated and gripped. Guide rails 14 for receiving and guiding the gripper claw elements 20 are preferably formed at uniform angular intervals along the inner annular side of the body 12. In the illustrated design, three guide rails 14 are formed as an example.

[0031] existFigure 1 and Figure 2 For clarity, the gripper element 20 is inserted into only one guide rail 14. According to the invention, the guide rail 14 in the body 12 is formed as a partially cylindrical guide channel 15, i.e., a guide channel 15 having cylindrical or partially cylindrical channel walls, wherein the corresponding guide channel 15 opens toward the interior 13. Here, the opening width W of the guide channel 15 is smaller than the cylinder diameter, which corresponds to the maximum channel width of the guide channel 15, wherein an undercut is formed in the guide channel 15.

[0032] Matching the shape of the guide channel 15, the gripping claw element 20 is formed with a cylindrical or partially cylindrical guide body 22 having a guide surface 24. The outer diameter of the guide body 22 mates with the inner diameter of the associated guide channel 15, so that the corresponding gripping claw element 20 is precisely and displaceably mounted in the guide channel 15.

[0033] The guide rail 14 or guide channel 15 each has a longitudinal or central guide axis, each angled relative to the central axis of the annular body 12. This angled arrangement ensures that axial displacement of the gripper element 20 within the guide channel 15 also results in radial displacement of the gripper element 20 relative to the central axis. This type of radial adjustment can, for example, bring the gripping surface 26 formed in the gripper element 20 into contact with the outer side of the drill pipe element to be gripped. In this way, frictional engagement retention of the drill pipe element within the annular body 12 is achieved.

[0034] In order to adjust or shift each gripper element 20 individually, these gripper elements 20 may have a hook arrangement 32 in their rear region, via which the gripper elements 20 can be connected to Figure 1 and Figure 2 The actuator is not shown. The hook arrangement 32 can be integrally formed on the gripper element 20 by inserting into the groove-shaped recess 34, or it can be attached to the gripper element 20 as a separate component.

[0035] Figure 3 An example of a clamping head arrangement 10 according to the present invention is shown, the clamping head arrangement 10 having as follows Figure 1 and Figure 2 The annular body 12 is shown in the figure. A gripping claw element 20, movable within the annular body 12, is held on the annular actuator 40 at its rear end region via a hook arrangement 32. For this purpose, a bracket-like receiving mount 36 is attached to the front side of the annular actuator 40 and forms a receiving window 37 into which the hook arrangement 32 engages. Connecting devices 30 for gripping the claw element 20 on the annular actuator 40 are formed free from the hook arrangement 32 and the associated receiving mount 36.

[0036] On its rear side away from the gripper element 20, the annular actuator 40 rotates together with the drive flange 46, and torque can be transmitted by a rotary drive (not shown) through the drive flange 46. Furthermore, the annular actuator 40 can be axially displaced relative to the center of the gripper head arrangement 10 or the borehole axis (not shown in detail) via at least one adjusting cylinder 50.

[0037] The annular body 12 has an end ring 18 on its front side, which surrounds the interior 13 in an annular shape. On its rear side opposite to the front side, the annular body 12 is securely connected to the drive flange 46 via a connecting sleeve 19 for transmitting torque, particularly relatively high drilling torque. The annular actuator 40 is displaceably arranged on the outside of the connecting sleeve 19.

[0038] By means of at least one adjusting cylinder 50, the annular actuator 40 is axially displaced, and each gripping claw element 20 is displaced via a corresponding connecting device 30 in a partially cylindrical guide channel 15. Figure 3 Not shown in detail. Because the guide channel axis is arranged at an angle relative to the central axis of the gripper head arrangement 10, the individual gripper claw elements 20 are also radially adjusted in this relationship.

[0039] By extending at least one actuating cylinder 50 (which may be particularly a hydraulic cylinder), the actuator 40, together with the gripping claw elements 20, can move axially downward toward the end ring 18, wherein each gripping claw element 20 can slide radially inward toward the inner chamber 13 and can radially clamp the drill rod element disposed there and hold it in a frictional engagement. In this way, the drilling torque from the drive flange 46 can be transmitted to the rod element clamped in this manner.

[0040] By retracting at least one adjusting cylinder 50, the annular actuator 40 can be moved rearward again accordingly, wherein the gripping claw elements 20 are axially retracted and also radially outward returned to their initial positions. In this reset position, the linkage elements can be removed from the gripping head arrangement 10 again, and new elements can be inserted.

Claims

1. Clamping head arrangement, in particular for clamping a drill rod element, having - a plurality of clamping jaw elements (20), each of which has a clamping surface (26) which is in particular designed for clamping contact with a contact side of the drill rod element, and - a guide track (14) in the main body (12) for the clamping jaw elements (20), wherein the guide track (14) is angled with respect to a central axis of the clamping head arrangement (10) such that a displacement of the clamping jaw elements (20) along the guide track (14) results in an axial and radial displacement of the clamping jaw elements (20) with respect to the central axis, wherein - the clamping jaw elements (20) are each designed with a cylindrical or partially cylindrical guide body (22), and - the guide track (14) in the main body (12) is formed as a partially cylindrical guide channel (15) in each of which a clamping jaw element (20) with the cylindrical or partially cylindrical guide body (22) is displaceably mounted.

2. Clamping head arrangement according to claim 1, wherein - the partially cylindrical guide channel (15) is open on a side facing the drill rod element to be clamped. - a body (12) having a guide track (14) along which the clamping jaw element (20) is displaceably mounted, wherein 3. Clamping head arrangement according to claim 1 or 2, wherein - the main body (12) is designed annularly with a free interior (13) for receiving the drill rod element and the guide channel (15) opens into the interior (13).

4. Clamping head arrangement according to claim 1 or 2, wherein - a tubular drill rod element can be clamped on the inside.

5. Clamping head arrangement according to claim 1 or 2, wherein - the clamping jaw elements (20) are connected to at least one actuator (40) which is mounted displaceably with respect to the main body (12) for displacing the clamping jaw elements (20).

6. Clamping head arrangement according to claim 5, wherein - the at least one actuator (40) is displaceable axially by means of at least one actuating cylinder (50), in particular a hydraulic cylinder.

7. Clamping head arrangement according to claim 5, wherein - each clamping jaw element (20) is connected with play to the actuator (40) via a connecting device (30).

8. Clamping head arrangement according to claim 7, wherein - a hook arrangement (32) is formed on a rear region of each clamping jaw element (20) to form the connecting device (30) and engages in an associated receiving mount on the actuator (40).

9. Clamping head arrangement according to claim 1 or 2, wherein - the clamping jaw arrangement for forming a drill drive arrangement, in particular on a drill drive carriage, can be driven rotationally via at least one rotary drive.

10. Drilling device for creating a borehole, in particular in the ground, having at least one drill rod element, wherein - a clamping head arrangement (10) according to any one of claims 1 to 9 is provided. ​ ​ ​ ​ The main body (12) is designed in the form of a shaft or a block with an outer circumferential side in which the part-cylindrical guide channel (15) with the clamping jaw elements (20) is arranged, wherein ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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