EP3798367B1 - Slotted wall gripper, method for operating same, and civil engineering method - Google Patents

Description

The invention relates to a trench wall grab with a skeleton-like guide frame, a connecting device on an upper end area of the guide frame for suspending the trench wall grab and two grab buckets, which are arranged on a lower end area of the guide frame and each move around an inner bucket pivot bearing between an open pick-up position for picking up soil material and can be pivoted to a closed position in which the gripper shovels abut one another to grip the picked-up soil material, according to the preamble of claim 1.

The invention also relates to a method for operating a trench wall grab with a framework-like guide frame, a connecting device for suspending the trench wall grab on an upper end area of the guide frame and two grab buckets, which are arranged on a lower end area of the guide frame and each move around a bucket pivot bearing between an open receiving position for picking up soil material and a closed position in which the grab buckets abut one another for embracing the picked up soil material, wherein the diaphragm wall grab is lowered into a soil with the grab buckets open, and the grab buckets are closed while picking up soil material and the diaphragm wall grab is raised upwards , according to the preamble of claim 12.

Finally, the invention also relates to a civil engineering method according to claim 13.

A generic diaphragm wall grab is, for example, from EP 1 950 353 A1 out. In this known diaphragm wall grab, the grab scoops are pivotably mounted on a lower bearing area of the guide frame. To open and close the gripper scoops, diagonally extending linkage levers are provided, which are articulated on the one hand on the gripper scoops and on the other hand on an actuating carriage. The actuating carriage is mounted on the guide frame in a vertically displaceable manner and can be displaced between a lower position and an upper position by means of a hydraulic cylinder. In the lower position of the actuating carriage, the gripper scoops are pivoted downwards about the pivot bearing and closed, while in the upper position of the actuating carriage the gripper scoops are pulled up and pivoted open about the pivot bearing.

In this known diaphragm wall grab, an axial length of the diaphragm wall grab when the grab scoops are closed is greater than an axial length of the diaphragm wall grab when the scoops are open.

The cross-section of the guide frame is adapted to the cross-section of the trench, so that the trench wall grab can guide itself through the guide frame with its contact surfaces in the trench.

In order to ensure the best possible guidance of the slurry wall grab in the prepared slot, the guide frame must have a certain height, which can be up to 10 m and more. This can limit the use of a diaphragm wall grab, since there must be enough free space above the ground.

At certain locations, such as under penetrations or in buildings, the free space above ground can be limited so that only diaphragm wall grabs with a correspondingly short vertical length can be used. Basically, it is known to reduce the skeleton-like guide frame accordingly in order to reduce the axial length of a trench wall grab. However, this is only possible to a certain extent, since otherwise an adequate guiding function of the box-like guiding frame is impaired.

From the GB 2 126 981 A another generic trench wall grab with a framework-like guide frame emerges, with which the trench wall grab is guided in the slot. In this diaphragm wall grab, the grab buckets are pivotably mounted on pivot bearings which are fixedly arranged on the guide frame. To open and close the gripper scoops, linkage rods are provided which can be actuated via a carriage which is displaceably mounted in the guide frame via lateral rollers and is thus guided. The carriage is moved via a block and tackle arrangement with deflection rollers over which a traction cable is guided.

the DE 38 05 868 A1 teaches a trench wall grab with a cable suspended guide frame for guiding in the trench. Within the guide frame, a grab shovel carrier can be moved and is mounted in a height-adjustable manner using hydraulic cylinders. The grab shovels are mounted on the grab shovel carrier and can be actuated by means of actuating cylinders which are articulated on the one hand on the grab shovels and on the other hand on the grab shovel carrier.

the UK799,519 relates to a non-generic gripper arrangement which is not suitable for guided use in a slot.

From the DE 21 61 401 A1 a diaphragm wall grab is known which has a reduced working height. To reduce the vertical length of the diaphragm wall grab For example, an outer part of the framework-like guide frame is designed to be foldable, with the guide frame being able to be folded away to the side when the diaphragm wall grab is lifted out of the slot to reduce the structural height. The actuation of the gripper scoops, which are linked to a fixed position of the guide frame with their inner pivot points, ie the pivot points assigned to the closing edge, also takes place via link rods attached laterally, ie further outside, to the gripper scoops. These are connected to an actuating carriage that is moved by an actuating cable. The grab shovels are pushed down to close and pulled up to open.

A folding mechanism for the guide frame is fundamentally complex and also impairs the stability of the framework-like guide frame, which should have the highest possible rigidity.

From the EP 2 848 740 B1 a diaphragm wall grab with two pairs of shovels lying one inside the other is known. The inner pair of shovels can be raised after filling, so that another gripping process can be carried out with the outer pair of shovels.

The invention is based on the object of specifying a trench wall grab, a method for operating such a trench wall grab and a civil engineering method which enable reliable operation of a trench wall grab even at a limited working height.

According to the invention, the object is achieved by a trench wall grab having the features of claim 1, a method for operating the trench wall grab according to claim 12 and a civil engineering method according to claim 13. Preferred embodiments of the invention are specified in the respective dependent claims.

The diaphragm wall grab according to the invention is characterized in that, for pivoting the grab shovels, the inner shovel swivel bearings are arranged on at least one bearing carriage, which is mounted displaceably relative to the guide frame between a lower carriage position and an upper carriage position, and that the grab shovels each have at least one outer linkage lever with the Guide frames are connected.

A basic idea of the invention is to bring about the displacement movement for opening and closing the grab shovels by vertically adjusting the inner pivot bearing of the grab shovels. The inner pivot bearings are arranged on at least one bearing carriage, which is slidably mounted between an upper carriage position and a lower carriage position. This considerably simplifies the mechanics of the gripper, since only one adjustment movement has to be generated for the at least one carriage.

In this case, the guide frame can also be designed as a largely rigid frame in the form of a box, with contact or guide surfaces in particular being provided for contact with the walls of the slot. By moving the bearing carriage upwards, the gripper scoops can be closed and pushed downwards to open them.

When the gripper shovels are actuated by moving the bearing carriage itself, it is expedient according to the invention for the gripper shovels to be connected to the guide frame via at least one linkage lever. When the gripper scoops are displaced by the bearing carriage, on which the gripper scoops are pivotally articulated, the linkage levers cause the gripper scoops to be pivoted about their pivot bearings into the desired closed position or the receiving position. When the bearing carriage with the gripper scoops is pushed up, a closing movement can be effected and when it is pushed down, an opening movement of the gripper scoops can be effected.

In this design, the outer pivot point does not move on a circular path, but on a superimposition of a circular path and vertical movement of the center of the circle ("inner pivot bearing"). As a result, the lowest point of the grab shovel moves upwards during closing, which means that the shovel height when closed is smaller than when it is open or during the closing process.

A preferred embodiment of the invention consists in that an actuating device is provided for pivoting the gripper shovels between the pick-up position and the closed position. The actuator can be any Be linear drive or a suitable rotary drive, which causes a pivoting of the grab shovels directly or via an actuating mechanism.

In principle, the actuating device can have a traction or actuating cable with which the gripper shovels can be pivoted. According to a development of the invention, it is particularly preferred that the actuating device has at least one actuating cylinder, in particular a hydraulic cylinder. With a hydraulic cylinder, high actuating forces can be applied in a limited installation space. A separate actuating cylinder can preferably be provided for each grab shovel, which swivels it.

According to a further development according to the invention, a particularly efficient construction of the trench wall grab is achieved in that the at least one actuating cylinder is arranged on the one hand on the grab frame and on the other hand on the bearing carriage. If an actuating cylinder, in particular a hydraulic cylinder, is arranged on the bearing carriage, this can serve as an actuating carriage for pivoting the gripper shovels. With the at least one actuating cylinder, both a change in the vertical length of the trench wall grab and a pivoting movement of the grab scoops can be effected by moving the bearing carriage.

According to a development of the invention, it is preferred that two adjusting cylinders are provided, which are arranged symmetrically to one another with respect to a longitudinal axis of the gripper frame. The actuating cylinders can be arranged at an angle to a vertical center plane of the diaphragm wall grab and in particular act directly on the guide frame on the one hand and on the bearing carriage or on the grab shovels on the other.

Efficient operation of the diaphragm wall grab can be achieved according to one embodiment of the invention in that the grab shovels are open in the pick-up position when the storage carriage is moved to the lower carriage position, and that the grab shovels are closed in the closed position when the storage carriage is in the upper carriage position is shifted. In this arrangement, the trench wall grab has a closed grab bucket less vertical length than when the grab buckets are open. According to the invention, a reduction in the vertical length can result when the gripper scoops are closed by pivoting the gripper scoops downwards due to the arrangement of the pivot bearing and articulation bearing. In this way, the diaphragm wall grab can have the smallest possible vertical length or height, especially when exiting a trench above the ground, so that the diaphragm wall grab can also be used in cramped conditions with a limited working height.

In principle, the bearing carriage, on which the gripper shovels are articulated, can be mounted in any desired manner. In one embodiment of the invention, it is particularly advantageous that the bearing carriage can be displaced on the guide frame along a linear guide, which runs parallel to a central longitudinal axis of the guide frame. Correspondingly, the at least one actuating cylinder can be arranged centrally and parallel to the central longitudinal axis, so that actuation of the bearing carriage with as little lateral force as possible is ensured.

In order to avoid jamming, it is expedient here for the linkage lever to be articulated on the one hand on the guide frame and on the other hand on the grab shovel. Thus, the linkage lever itself can perform a certain pivoting movement in relation to the guide frame and also the gripper shovels. The articulated storage can be done via bushings or roller bearings.

In principle, it is possible according to the invention that the two gripper scoops are each mounted on bearing carriages that can be displaced separately from one another, as a result of which an asymmetrical gripper scoop movement could be produced. According to a further development according to the invention, a particularly efficient construction of the diaphragm wall grab results from the fact that the bucket swivel bearings of the grab buckets are arranged close to a central longitudinal axis on a common bearing carriage. The bearing carriage and the entire arrangement of the grab shovels are symmetrical to a central longitudinal plane of the trench wall grab, which usually extends vertically.

The aim of the invention is in particular that the vertical length of the trench wall grab with closed grab buckets in the closed position is smaller than the vertical length of the diaphragm wall grab with the grab buckets open in the pick-up position.

The invention also includes a construction machine with a carrier device, the diaphragm wall grab described above according to the invention being vertically adjustable on the carrier device. The carrier device can be a stationary guide or a movable carrier device, which has a caterpillar chassis, for example. The diaphragm wall grab can be mounted in a vertically adjustable manner, for example on a crane boom or mast, in particular by means of a guide rope or a guide rod.

The method for operating a diaphragm wall grab is characterized in that the vertical length of the diaphragm wall grab with closed grab buckets when lifting is smaller than the vertical length of the diaphragm wall grab with open grab buckets when lowering. In this way, in particular, the vertical length of the trench wall grab can be reduced outside of a trench when the grab buckets are closed. This is particularly important when the grab bucket with picked up soil material is pulled out of the slot and moved to an unloading position. Advantageously, the grab scoops can be closed again after unloading and moved back into the slot in the closed and thus vertically compact form.

A preferred operating sequence for actuating the diaphragm wall grab and digging out soil material has the following steps in particular:
A closed gripper is positioned over the slot to be made. A first guide trench for receiving at least the lower portion of the diaphragm wall grab can be previously dug into the ground at the position.

The grab shovels can then be opened to pick up the soil material, with the diaphragm wall grab being able to assume a greater vertical length.

The diaphragm wall grab can be lowered with the grab buckets open until it comes into contact with the ground.

The grab shovels of the diaphragm wall grab are then closed by pulling the grab shovels upwards. The slurry wall grab can be lowered further. Closing the grab buckets while the grab buckets are filling with soil allows the diaphragm wall grab to resume its shorter vertical length.

The diaphragm wall grab is then lifted with the grab buckets closed and moved to an unloading point.

The diaphragm wall grab is unloaded by opening the grab buckets. The grab shovels can then be closed again and swiveled back to the working position in order to carry out another excavation process.

The invention further relates to a civil engineering method in which a trench is created in the ground by means of the trench wall grab according to the invention described above. In particular, a large number of slits can be created next to one another, so that overall a slit that is longer in the horizontal direction is created. Material is excavated as previously described.

It is particularly preferred that the slot is filled with a hardenable suspension to form a slot wall. In particular, a concrete mass can be introduced into the slot. Before the mass hardens, reinforcement elements, such as metallic lattice cages or steel girders, can be let into the slot. The diaphragm wall can be designed as an enclosing wall for large construction pits, a cut-off wall or as a retaining wall.

A civil engineering method within the meaning of the invention also includes mining of mineral resources by means of the diaphragm wall grab. Raw materials contained in the soil, such as e.g. B. ores or diamonds are filtered out of the excavation and the slot is filled with the overburden.

Fig. 1

eine perspektivische Ansicht eines erfindungsgemäßen Schlitzwandgreifers mit geöffneten Greiferschaufeln;

Fig. 2

eine Vorderansicht des Schlitzwandgreifers von Fig. 1;

Fig. 3

eine perspektivische Ansicht des erfindungsgemäßen Schlitzwandgreifers mit geschlossenen Greiferschaufeln;

Fig. 4

eine Vorderansicht des Schlitzwandgreifers von Fig. 3; und

Fig. 5

eine schematische Ansicht des Schlitzwandgreifers gemäß Fig. 4, wobei gleichzeitig der Zustand mit geöffneten Greiferschaufeln mit gestrichelter Linienführung gemäß Fig. 2 dargestellt ist.

The invention is further described below with reference to a preferred exemplary embodiment, which is illustrated schematically in the drawings. In the drawings show:

1

a perspective view of a trench wall grab according to the invention with open grab buckets;

2

a front view of the slurry wall grab from 1 ;

3

a perspective view of the trench wall grab according to the invention with closed grab buckets;

4

a front view of the slurry wall grab from 3 ; and

figure 5

a schematic view of the trench wall grab according to FIG 4 , wherein at the same time the state with open grab buckets with dashed lines according to FIG 2 is shown.

An embodiment of a trench wall grab 10 according to the invention according to the Figures 1 to 4 has a framework-like, box-shaped guide frame 12 on which plate-shaped guide surfaces 14 are arranged on the side areas. The guide surfaces 14 serve to independently guide the trench wall grab 10 in the prepared slot with a rectangular cross section, the guide surfaces 14 coming to rest on the side walls of the prepared slot in a basically known manner. Laterally extendable control plates 16 can also be arranged on the guide frame 12 in order to influence a position of the trench wall grab 10 within the trench in a likewise known manner and to control the course of the trench to be created to a certain extent.

A connecting device 18 is arranged at an upper end region of the guide frame 12, with which the diaphragm wall grab 10 is suspended, for example, on suspension cables 19 on a carrier device, not shown. Energy can also be supplied and controlled via the connecting device 18, with corresponding hydraulic lines, electrical lines and data lines not being shown in the figures.

In a lower area of the diaphragm wall grab 10, two spoon-like grab scoops 20 are arranged so that they can each pivot about an inner pivot bearing 22. On the blade outer edges of the gripper blades 20, removal teeth 24 are arranged interchangeably in a basically known manner. In the in the figures 1 and 2 In the illustrated open position of the grab scoops 20, soil material is picked up over a rectangular cross-sectional area of the slot to form the slot.

According to the invention, the pivot bearing 22 of the gripper scoops 20 are not attached directly to the guide frame 12, but rather to a bearing carriage 30 which is mounted on the guide frame 12 so that it can be displaced vertically along a linear guide 34. The box-shaped bearing carriage 30 has corresponding linear guide rails 32 for this purpose. The linear guide 34 and the guide rails 32 extend parallel to a vertical longitudinal axis of the guide frame 12.

For the vertical displacement of the bearing carriage 30, two hydraulic actuating cylinders 42a, 42b are provided in the illustrated trench wall grab 10 according to the invention, which are arranged in a V-arrangement on the trench wall grab 10 with respect to a central longitudinal plane of the guide frame 12, as illustrated in FIGS figures 2 and 4 is shown. The hydraulic actuating cylinders 42a, 42b are pivoted on the one hand with their cylinder housing on the upper region of the guide frame 12 on a first connecting bearing 43 and on the other hand with their piston rod on a second connecting bearing 44 on the bearing carriage 30, such as from 4 emerges. If the positioning cylinders 42a, 42b are arranged in a V, a twisting device can be arranged in the free space between the positioning cylinders 42a, 42b. With the twisting device, the grab scoops 20 can be twisted about the vertical axis by preferably 180°.

By means of the hydraulic actuating cylinders 42a, 42b, the bearing carriage 30 with the gripper shovels 20 articulated thereon can be moved into a lower end position, which in the figures 1 and 2 is shown. In this lower end position, the pivot bearings 22 of the grab shovels 20 are pressed downwards, with the grab shovels 20 being moved into an open position for picking up soil material. By moving the bearing carriage 30 upwards by retracting the hydraulic actuating cylinders 42a, 42b, the pivot bearings 22 of the grab shovels 20 are moved upwards into an upper end position, which is in the Figures 3 and 4 is shown.

In the exemplary embodiment shown, a linkage lever 46 is arranged on the side of each of the gripper scoops 20 . The two linkage levers 46 are each pivotable via a first pivot bearing 47 with the guide frame 12 and on the other hand via a second pivot bearing 48 pivotable with the respective gripper bucket 20 connected. When the storage carriage 30 is moved upwards by the hydraulic actuating cylinders 42a, 42b, in the exemplary embodiment shown, the linkage lever 46 causes the gripper shovels 20 to move from the open receiving position according to FIGS figures 1 and 2 simultaneously with the shifting of the pivot bearings 22 upwards into a closed position in which the grab buckets 20 are closed for picking up soil material, as illustrated in FIGS Figures 3 and 4 is shown.

In the exemplary embodiment shown, the hydraulic actuating cylinders 42a, 42b and the linkage levers 46 together with the displaceable bearing carriage 30 thus form an actuating device 40, by means of which the gripper shovels 20 can be actuated for opening and closing.

As can be clearly seen from the schematic representation of figure 5 As can be seen, in the illustrated diaphragm wall grab 10 according to the invention, moving the bearing carriage 30 downwards can cause the swivel bearings 22 of the grab buckets 20 to move downwards, which leads to the grab buckets 20 opening. This opening state is in figure 5 shown with dashed lines.

Conversely, by moving the bearing carriage 30 upwards by retracting the hydraulic actuating cylinders 42a, 42b, the swivel bearings 22 with the grab shovels 20 can be pulled upwards, with the linkage lever 46 causing the grab shovels 20 to pivot towards one another into a closed position is effected, which in figure 5 is shown with the solid line.

The comparison of the two states of the diaphragm wall grab 10 with the closed position on the one hand and the open position of the grab shovels 20 on the other hand makes it clear that the configuration according to the invention makes it possible to achieve an axial length or height of the diaphragm wall grab 10 in the closed position with the grab shovels 20 closed, which is less than is a vertical length or height of the trench wall grab 10 with the grab buckets 20 open.

Thus, in the closed position, in which it is usually pulled out of the trench, the trench wall grab 10 has a minimum vertical length or height, so that a particularly compact construction of the trench wall grab 10 is provided.

This can be used in particular under cramped spatial conditions, in particular with a limited working height.

Claims (14)

1. Diaphragm wall grab having

   - a scaffold-like guide frame (12),

   - a connecting means (18) located in an upper end region of the guide frame (12) for suspension of the diaphragm wall grab (10) and

   - two grab shovels (20) which are arranged in a lower end region of the guide frame (12) and are each pivotable about an inner shovel pivot bearing (22) between an open receiving position for receiving ground material and a closure position, in which the grab shovels (20) rest against each other to grasp the received ground material, wherein the grab shovels (20) are each connected to the guide frame (12) via at least one outer linkage lever (46),

   characterized in that
   in order to pivot the grab shovels (20) the inner shovel pivot bearings (22) are arranged on at least one bearing sledge (30) which is supported in a displaceable manner on the guide frame (12) between a lower sledge position and an upper sledge position.
2. Diaphragm wall grab according to claim 1,
   characterized in that
   an actuating means (40) is provided to pivot the grab shovels (20) between the receiving position and the closure position.
3. Diaphragm wall grab according to claim 2,
   characterized in that
   the actuating means (40) has at least one positioning cylinder (42a, 42b), in particular a hydraulic cylinder.
4. Diaphragm wall grab according to claim 3,
   characterized in that
   the at least one positioning cylinder (42a, 42b) is arranged on the one hand on the guide frame (12) and on the other hand on the bearing sledge (30).
5. Diaphragm wall grab according to claim 3 or 4,
   characterized in that
   two positioning cylinders (42a, 42b) are provided which are arranged symmetrically to a longitudinal axis of the guide frame (12).
6. Diaphragm wall grab according to any one of claims 1 to 5,
   characterized in that

   the grab shovels (20) are open in the receiving position when the bearing sledge (30) is displaced into the lower sledge position and

   in that the grab shovels (20) are closed in the closure position when the bearing sledge (30) is displaced into the upper sledge position.
7. Diaphragm wall grab according to any one of claims 1 to 6,
   characterized in that
   the bearing sledge (30) is displaceable on the guide frame (12) along a linear guide (34) which runs parallel to a central longitudinal axis of the guide frame (12).
8. Diaphragm wall grab according to any one of claims 1 to 7,
   characterized in that
   the linkage lever (46) is mounted in an articulated manner on the one hand on the guide frame (12) and on the other hand on the grab shovel (20).
9. Diaphragm wall grab according to any one of claims 1 to 8,
   characterized in that
   the shovel pivot bearings (22) of the grab shovels (20) are arranged close to a central longitudinal axis on a common bearing sledge (30).
10. Diaphragm wall grab according to any one of claims 1 to 9,
    characterized in that
    a vertical length of the diaphragm wall grab (10) with closed grab shovels (20) in the closure position is smaller than the vertical length of the diaphragm wall grab (10) with open grab shovels (20) in the receiving position or during the closing process.
11. Construction machine having a carrier implement,
    characterized in that
    on the carrier implement a diaphragm wall grab (10) according to any one of claims 1 to 10 is supported in a vertically adjustable manner.
12. Method for operating a diaphragm wall grab (10) according to any one of claims 1 to 10, having

    - a scaffold-like guide frame (12),

    - a connecting means (18) located in an upper end region of the guide frame (12) for suspension of the diaphragm wall grab (10) and

    - two grab shovels (20) which are arranged in a lower end region of the guide frame (12) and are each pivotable about a shovel pivot bearing (22) between an open receiving position for receiving ground material and a closure position, in which the grab shovels (20) rest against each other to grasp the received ground material,

    wherein the diaphragm wall grab (10) is lowered into a ground with open grab shovels (20) and

    on receiving ground material the grab shovels (20) are closed and the diaphragm wall grab (10) is lifted upwards,

    characterized in that

    a vertical length of the diaphragm wall grab (10) with closed grab shovels (20) during lifting is equal to or smaller than the vertical length of the diaphragm wall grab (10) with open grab shovels (20) during lowering.
13. Foundation engineering method,
    characterized in that
    a trench is produced in the ground by means of a diaphragm wall grab (10) according to any one of claims 1 to 10.
14. Foundation engineering method according to claim 13,
    characterized in that
    the trench is filled with a hardenable suspension to form a diaphragm wall.

Images