DEVICE FOR INSTALLING A FOUNDATION PILE

Description

[0001] The invention relates to a screw-in device for a screw foundation, which is attached to an excavator boom.

[0002] Screw-in devices, which are attached to an excavator boom arm, by means of which screw foundations can be screwed into the ground, are generally known, as they are also discussed by way of example in the publication WO 2013 / 014079 A1.

[0003] US 4,199,033 describes a screw foundation to be installed in the ground using a rotary device attached to an excavator boom. The rotary device, in the form of a hydraulic drive unit, is mounted on the excavator boom. On the side of the boom facing the ground, a clamping device for the screw foundation is located. The screw foundation is clamped in this device and then screwed into or out of the ground by the excavator using the hydraulic drive unit. The rotary device causes the screw foundation to rotate around its longitudinal axis. A pivot axis extending radially from the drive unit runs along the side of the rotary device opposite the screw foundation, i.e., in its upper part. This allows the screw foundation to be installed in any direction, including horizontally, within a given area of ​​the ground.To allow the rotating mechanism to pivot freely relative to its attachment to the excavator arm, this pivot axis is located in the upper section of the rotating mechanism and supported on both sides by angle brackets. Additionally, the front section of the excavator boom, together with the hydraulic drive unit and the screw foundation, can pivot laterally around another axis. All pivot axes are arranged so that they do not intersect. Furthermore, the pivot axis extending radially from the drive unit is located in the upper section of the rotating mechanism, thus positioning it relatively far from the center of gravity of the rotating mechanism. With these three drive axes, it is possible to drive a screw foundation into the ground at different angles, depending on the requirements.This known device, however, has the disadvantage that while it allows for maximum deflection of the excavator arm, this is associated with a higher tilting moment of the screw foundation. During installation, the screw foundation can therefore wobble, making reliable and secure installation at a desired, defined angle difficult. The arrangement of the three pivot axes without an intersection results in a skew torque, which arises when the excavator boom is pushed downwards by a feed force as soon as there is an offset between the load application point and the insertion axis. This skew torque causes the screw foundation to deviate from the desired installation direction. With the known device, this can only be compensated for by the excavator operator.This means that the screwing-in process is highly dependent on the excavator operator's skill in carrying out the screwing-in process in the desired manner.

[0004] US Patent 2011 / 0 225 855 A1 describes a device for inserting a burial container in the form of a large screw foundation. The screw foundation is equipped with a pivoting clamping device and can be erected in any desired insertion direction by screwing it in along the longitudinal axis of the coffin container and pivoting it about a vertical axis oriented longitudinally to the insertion vehicle, as well as about a pivotable direction transverse to this axis. In this position, it can also be screwed into the ground. For this purpose, hydraulic cylinders connected to the clamping device are provided on the outside of the insertion vehicle. To prevent uneven tightening torque during insertion, these cylinders must be adjusted by the operator using their skill.

[0005] The object of the invention, in contrast to this known device, is to create such an arrangement of a screwing device together with such a suspension on the excavator boom arm, by means of which the screwing in of the screw foundation occurs with as little twisting torque as possible.

[0006] This problem is solved by a screw-in device attached to an excavator boom arm for screwing in a screw foundation with the features according to claim 1. Advantageous further developments are defined in the dependent claims.

[0007] According to the invention, the screw-in device for a screw foundation, attached to an excavator boom arm, is designed as a gimbal suspension and includes a rotary drive for receiving the screw foundation, i.e., with a clamping mechanism. According to the invention, the gimbal suspension is designed such that the screw foundation is rotatable about its longitudinal axis for screwing in or unscrewing and is pivotable about a first pivot axis, which is located at the front end of the excavator boom arm, the first pivot axis intersecting the longitudinal axis of the screw foundation. Additionally, the gimbal suspension is pivotable about a second pivot axis, which is arranged such that it penetrates the rotary drive in its radial direction. The second pivot axis is located in the region of the rotary drive's center of gravity, which is preferably located in the lower part of the rotary drive facing the screw foundation.The second pivot axis has at least one common intersection point with the longitudinal axis of the screw foundation.

[0008] Because both pivot axes of the gimbal suspension, i.e., the first and second pivot axes, are not offset from the longitudinal axis of the screw foundation, the torque generated by the feed force when the excavator boom is pushed downwards can be avoided or minimized. This pulling torque occurs precisely when there is an axial offset between the load application point and the insertion axis. Therefore, insertion using the device according to the invention is essentially free of pulling torque. The deeper the second pivot axis is positioned in the rotary drive relative to the clamping point of the screw foundation, the lower the resulting torques and thus the easier it is to minimize the bending moment acting on the screw foundation during the insertion process. This is particularly relevant if the excavator operator intervenes to correct any obstacles encountered in the ground.Ultimately, the goal is to minimize the moment acting on the flange, i.e., at the clamping point of the screw foundation. Therefore, to achieve the problem described in the invention, it is crucial that the arrangement of the axes relative to each other is such that at least the first pivot axis and the second pivot axis each intersect the longitudinal axis of the screw foundation, although an offset between them is permissible. As long as both pivot axes intersect the longitudinal axis of the screw foundation, the skew torque can be avoided or at least kept very small. Furthermore, a low pivot axis reduces the effective buckling length. This results in a lower risk of buckling even with higher feed forces.

[0009] A particularly preferred embodiment exists when not only the second pivot axis intersects the longitudinal axis of the screw foundation, but also the first pivot axis passes through this intersection. With such an arrangement of the pivot axes relative to each other, it can be ensured that the screw foundation can be screwed into the ground in the desired direction without requiring any special skills from the excavator operator.

[0010] If the second pivot axis in the rotary drive is positioned as far down as possible, near its center of gravity, then free pivoting of the rotary drive is not possible due to its fork-shaped or ring-shaped mounting on the excavator arm. This is unless, for example, a fork-shaped mounting with long forks is used, which could introduce instabilities and vibrations. However, since the first pivot axis is located at the front end of the excavator boom via a joint, the installation device—that is, the rotary drive together with the screw foundation—can be rotated laterally relative to the excavator boom and, in this position, even screwed into a horizontal position in a soil area, such as the side walls of a trench.

[0011] Preferably, the fork provided as part of the gimbal suspension is arranged on the head of the excavator boom arm in such a way that the second pivot axis runs through the fork ends in such a way that it intersects the longitudinal axis of the screw foundation.

[0012] According to a further embodiment, a ring is provided which houses the rotary drive inside, functioning identically to the one described above, with the second pivot axis also intersecting the longitudinal axis of the screw foundation. The ring is formed, so to speak, by extending the two fork ends around the rotary drive, which preferably has a cylindrical outer shape, to such an extent that the fork ends merge into one another, thus forming a closed ring.

[0013] In order for a screw foundation to be screwed in horizontally or in a direction where the longitudinal axis of the screw foundation runs in the direction of the ground surface, the gimbal suspension can be pivoted accordingly far around the first pivot axis.

[0014] Further advantages, details, and possible applications of the present invention will now be explained with reference to the following drawing. The drawing shows: Figure 1 shows a screw-in device in the form of a gimbal suspension for screw foundations according to the invention, mounted on an excavator boom arm in a three-dimensional view; Figure 2 shows the embodiment according to Figure 1 in side view; Figure 3 the embodiment according to Figure 1Figure 4 shows a top view with a fork-shaped bracket for the gimbal suspension; Figure 4 shows a further embodiment in which the fork-shaped attachment of the gimbal suspension has a ring-shaped bracket; Figure 5 shows the screw-in device with a partially screwed-in screw foundation showing the acting shear force and moment diagram for a gimbal suspension according to the invention; and Figure 6 shows a screw-in device with a suspension mounted above the rotary drive showing the shear force and moment diagram.

[0015] In Figure 1A three-dimensional representation shows a screw-in device 1 for a screw foundation 2, which is mounted as a gimbal suspension with a rotary drive 4 on an excavator boom arm 3 by means of a fork-like bracket 9. The screw foundation 2 is attached to the rotary drive 4 by means of a clamping device 8, specifically at the flange area of ​​the screw foundation 2. The screw-in device 1, in the form of a gimbal suspension, allows the screw foundation 2 to be rotated about its longitudinal axis 5 for the purpose of screwing it in or out. Furthermore, the screw foundation 2, together with the gimbal suspension and thus with the rotary drive 4, can be pivoted about a first pivot axis 6, and thus in a transverse direction to the longitudinal extension of the excavator boom arm 3.

[0016] Furthermore, the turning device 1 is pivotable about a second pivot axis 7 in a plane defined by the longitudinal extension of the excavator boom arm 3. The rotary drive 4 is held laterally by a bracket in the form of a fork 9, which is attached at one end to the head of the excavator boom arm 3 and through which the second pivot axis 7 runs radially at the opposite end of the fork through the rotary drive 4. The pivot axes 6 and 7 are arranged such that both the first pivot axis 6 and the second pivot axis 7 intersect the longitudinal axis 5 of the screw foundation 2, i.e., they have at most an offset from each other along the longitudinal axis 5.Since both pivot axes intersect the longitudinal axis 5, the skew pulling moment, which arises from the feed force when pushing the excavator boom arm 3 downwards as soon as there is an axial offset of the load application point to the turning axis, is low.

[0017] Out of Figure 1 It is evident that the intersection of the second pivot axis 7 with the longitudinal axis 5 of the screw foundation 2 lies at the center of mass of the rotary drive 4, which is located in the lower region of the rotary drive 4. By "lower region" we mean that the lower part of the rotary drive 4, which points towards the flange of the screw foundation 2, is located close to the clamping device 8 on the flange of the screw foundation 2, i.e., it is positioned significantly further downwards than is known in prior art suspensions.

[0018] The disadvantage of such an arrangement is that, with the size of the fork 9 shown for attaching the rotary drive 4 within the gimbal suspension, the screw foundation 2 together with the rotary drive 4 cannot be pivoted far enough around the pivot axis 7 to align the screw foundation 2 in a direction parallel to the ground surface, i.e., even horizontally. This is because the upper part of the rotary drive 4 would collide with the front, head-end area of ​​the excavator boom 3.If the length of the fork 9 were extended so far in a direction parallel to the first pivot axis 6, it might be possible to pivot the rotary drive 4 through the area between the fork 9 and past the head of the excavator boom arm 3. However, the length of the fork arms could lead to instabilities and vibrations during operation, which would be particularly detrimental to the safe, clean, and angle-defined screwing of the screw foundation 2 into the ground. If, for example, the screw foundation 2 is to be installed in the ground essentially horizontally, a pivot about the first pivot axis 6 with the entire gimbal suspension at the head of the excavator boom arm 3 is possible, so that the screw foundation 2 can then be screwed in or unscrewed from the ground in a lateral direction, pointing towards the excavator boom arm 3.Bringing the screw foundation into a horizontal position makes it particularly easy to pick up and connect large screw foundations. The common intersection of the first pivot axis 6 with the longitudinal axis 5 of the screw foundation 2 is designated by reference numeral 12, whereas the common intersection between the second pivot axis 7 and the longitudinal axis 5 of the screw foundation 2 is shown with reference numeral 11.

[0019] According to a preferred embodiment, the intersection point 12 of the first pivot axis 6 with the longitudinal axis 5 of the screw foundation 2 and the intersection point 11 between the second pivot axis 7 and the longitudinal axis 5 of the screw foundation 2 form a common intersection point. This means that the first pivot axis 6, the second pivot axis 7, and the longitudinal axis 5 of the screw foundation 2 intersect at this common intersection point. In this case, screwing in the screw foundation 2 is particularly easy because the skew torque is small in this embodiment and is especially easy to manage when screwing in or unscrewing the screw foundation 2.

[0020] In Figure 2 is the embodiment according to Figure 1Shown in side view. The offset between the first longitudinal axis 6 and the second pivot axis 7, which runs radially through the mounting of the rotary drive 4, is clearly visible in the direction of the longitudinal axis 5 of the screw foundation 2. All other functions and movements correspond to those associated with Figure 1 They have been explained; therefore, they will not be repeated.

[0021] In Figure 3 is the embodiment according to the Figures 1 and 2Shown in plan view. Firstly, the second pivot axis 7 is shown, which runs radially through the rotary drive 4 via the fork 9 located at the front end of the excavator boom arm 3. Also shown is the first pivot axis 6, which is arranged essentially perpendicular to it and runs through the rotatably mounted head on the excavator boom arm 3 and simultaneously through the longitudinal axis 5 of the screw foundation 2 (not shown), which runs perpendicular to the plane of the drawing. Identical reference numerals denote identical parts.

[0022] In Figure 4 is a opposite to the Figures 1 to 3 A modified embodiment is shown. The axis paths and the gimbal suspension's mobility correspond to those of the embodiment according to the Figures 1 to 3. Only the fork-shaped mounting for the rotary drive 4 was modified in such a way that the ends of the fork 9 are extended around the rotary drive 4 and merge into one another, so that the mounting device for the rotary drive 4 is designed as a closed ring 10.

[0023] Figure 5Figure 1 shows a schematic representation of the shear force and moment diagrams for a gimbal suspension for the rotary device 1, i.e., the rotary drive 4 with the screw foundation 2 partially screwed into the ground according to the invention. The common intersection of the pivot axes 6 and 7 is shown, passing through the center of mass located in the lower region of the rotary drive 4. This minimizes the distance between the point of application of the moment and the flange of the screw foundation 2, to which the rotary drive 4 is attached. The shear force is constant for the entire area from the center of mass of the rotary drive 4 to the ground, while the moment increases linearly to the ground. The magnitude of the moment acting on the flange is qualitatively defined by the value 17 indicated by the double arrow. Reference numeral 15 represents the shear force diagram, and 16 represents the moment diagram.

[0024] In contrast, in Figure 6The suspension of a rotary device 4, as known in the prior art, is shown. There, the suspension of the rotary device 4 is arranged at the front end of the excavator boom arm above the rotary device 4, so that from the outset the screwing device, together with the screw foundation 2, tends to oscillate, which will ultimately also lead to an increased tendency to tilt during screwing. The rocking or tilting of the screw foundation 2 cannot, in any case, be readily compensated for by the excavator operator's special skills in operating the excavator. Figure 6It has been shown that the shear force distribution is constant over the entire area from the suspension to the ground surface, whereas the moment distribution increases linearly. The moment acting on the flange of the screw foundation 2 is shown qualitatively and is also indicated by the double arrow with reference numeral 17. The comparison between the designs according to the prior art Figure 6 with the training according to the invention according to Figure 5 shows that the moment generated in the area of ​​the flange during corrections by the excavator operator, which can cause damage to the screw foundation, is considerably greater in magnitude than during training according to Figure 5 . REFERENCE MARK LIST

[0025] 1 Screw-in device 2 Screw foundation 3 Excavator boom arm 4 Rotary drive 5 Longitudinal axis of screw foundation 6 First pivot axis suspension 7 Second pivot axis suspension 8 Clamping device 9 Fork 10 Ring 11 Intersection of second axis with longitudinal axis of screw foundation 12 Intersection of first axis with longitudinal axis of screw foundation 15 Shear force 16 Torque 17 Torque acting on flange

Claims

1. Screwing-in device (1) for a screw foundation (2), which is attached to an excavator boom arm (3) and has a suspension means which is formed as a gimbal suspension means which receives the screw foundation (2) and has a rotary drive (4), wherein the gimbal suspension means is designed such that the screw foundation (2) can be rotated about its longitudinal axis (5) for screwing in or unscrewing and can be swivelled about a first swivel axis (6) at the front end of the excavator boom arm (3), which intersects the longitudinal axis (5), characterized in that the gimbal suspension means can be swivelled about a second swivel axis (7) which penetrates the rotary drive (4) in its radial direction, wherein the second swivel axis (7) extends in the region of the centre of mass of the rotary drive (4) and has a common intersection point (11) at least with the longitudinal axis (5) of the screw foundation (2).

2. Screwing-in device (1) according to Claim 1, characterized in that the first swivel axis (6) intersects the second swivel axis (7).

3. Screwing-in device (1) according to Claim 1, characterized in that it receives the rotary drive (4) by means of a fork (9).

4. Screwing-in device (1) according to Claim 1, characterized in that it receives the rotary drive (4) by means of a ring (10) which encloses it.

5. Screwing-in device (1) according to one of Claims 1 to 4, characterized in that the gimbal suspension means can be swivelled about the first swivel axis (6) to such an extent that the longitudinal axis (5) of the screw foundation (2) runs in the direction of the ground surface, in which the screw foundation (2) can be mounted or dismantled.