Construction machine and method for forming holes

Abstract

The present invention relates to a civil engineering machine for forming a hole in the ground, comprising a machine frame, a holding device in the upper region of the machine frame for attaching and holding the civil engineering machine to a support cable or support rod, a drilling device having at least one rotatably drivable drilling member, which is arranged in the lower end region of the machine frame and is configured to excavate soil, a drive unit arranged on the machine frame for rotatably driving at least one drilling member, and a suction device for sucking the excavated soil upwards together with the liquid contained in the hole by means of a suction line, the suction device comprising at least one suction opening in the lower end region of the machine frame and a suction pump arranged on the machine frame. According to the present invention, the suction line leads to a flow splitting unit, which is arranged on the machine frame, and an upward discharge line and a return line for returning a part of the sucked liquid to the lower end region of the machine frame are connected to the flow splitting unit, and the flow splitting unit has a filter configured to pass the liquid containing the smaller excavated soil through the return line or the discharge line.

Description

Technical Field

[0001] The present invention relates to a civil engineering machine for forming a hole in the ground as described in the preamble of claim 1, comprising a machine frame, a holding device in the upper region of the machine frame for attaching and holding the civil engineering machine to a support cable or support rod, at least one rotatably drivable excavation member, an excavation device arranged in the lower end region of the machine frame and configured to excavate soil, a drive unit arranged on the machine frame for rotatably driving at least one excavation member, and a suction device for sucking the excavated soil upward together with the liquid contained in the hole via a suction line, the suction device comprising at least one suction opening in the lower end region of the machine frame and a suction pump arranged on the machine frame.

[0002] The present invention further relates to a method for forming a hole in the ground with a civil engineering machine as described in the preamble of claim 10, wherein the civil engineering machine comprises a machine frame, a holding device in the upper region of the machine frame for attaching and holding the civil engineering machine to a support cable or support rod, at least one rotatably drivable excavation member, an excavation device arranged in the lower end region of the machine frame and configured to excavate soil with at least one excavation member to form a hole in the ground, a drive unit arranged on the machine frame for rotatably driving at least one excavation member by the drive unit, and a suction device for sucking the excavated soil upward together with the liquid contained in the hole via a suction line, the suction device comprising at least one suction opening in the lower end region of the machine frame and a suction pump arranged on the machine frame.

Background Art

[0003] Examples of earthmoving machinery in use are, for example, trench cutters for forming so-called trench walls or cut-off walls that are not necessary for soil retention or water stoppage in an excavation pit. By using a trench cutter, the soil is excavated by a rotationally driven cutting wheel, sucked by a suction pump together with the surrounding support suspension or the cleaning liquid in the trench, and discharged to the ground. The discharged suspension or cleaning liquid can be removed from the excavated soil at a ground treatment plant, and the suspension or cleaning liquid is returned to the trench. Such trench cutters and such methods are known, for example, from Patent Document 1 or Patent Document 2.

[0004] In order to discharge the suspension or cleaning liquid from the cut trench, it is known, for example, from Patent Document 3, which is a patent in the same field, to suck the suspension or cleaning liquid together with the excavated soil by a suction pump on the frame of the cutter through a suction connection arranged between two pairs of cutting wheels.

[0005] The suction pump must be designed with an output so as to reliably discharge the excavated soil together with the surrounding liquid upward and out of the trench. As the trench gets deeper, the transport distance or height increases, so the work to be done by the suction pump also increases. Therefore, as the depth of the trench increases, a correspondingly powerful and thus expensive suction pump becomes necessary. However, for example, the installation space around the trench cutter is limited, so it is impossible to provide an infinitely large pump with a large pump drive unit. For this reason, it may be necessary to reduce the excavation speed of the cutter during excavation when the depth exceeds a certain level. By doing so, the amount of small pieces generated can be reduced and adapted to the limited transport capacity of the suction pump. However, this causes the excavation speed to drop and the progress of the construction work to slow down.

[0006] A problem corresponding to the above can also occur in an in-pit excavator in which a suction pump is arranged in the machine. Such in-pit excavators can be found in Patent Document 4 or Patent Document 5.

[0007] Finally, from Patent Document 6, there is known a shaft boring apparatus in which the portion of the cutting cooling liquid that should be separated by a multi-stage filter in a separator unit and conveyed to the ground surface via a downstream feed pump for purification is minimized.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Summary of the Invention

Problems to be Solved by the Invention

[0009] An object of the present invention is to identify a civil engineering machine and method for forming a hole in the ground particularly efficiently.

Means for Solving the Problems

[0010] This object is achieved, on the one hand, by a civil engineering machine having the features of claim 1 and, on the other hand, by a method having the features of claim 10. Preferred embodiments of the present invention are shown in each of the dependent claims.

[0011] The construction machine of the present invention is characterized in that a suction line leads to a flow splitting unit which is arranged on the machine frame, an upward discharge line and a return line for returning a part of the sucked liquid to the lower end region of the machine frame are connected to the flow splitting unit, and the flow splitting unit has a filter configured to pass the liquid containing smaller excavated soil through the return line or the discharge line.

[0012] The fundamental concept of the present invention lies in connecting a flow splitting unit in contact with the machine frame, preferably in the vicinity of the suction pump, to the suction line, from which an upward discharge line and a downward return line originate. The filter is arranged within the flow splitting unit, whereby a split flow of the liquid that may contain pieces smaller than a certain size of the excavated soil can pass through the return line or the discharge line. Another split flow containing larger soil pieces is directed to the other line.

[0013] By arranging the filter, it is possible to increase the density of the soil in the suspension to be discharged upward. Thus, the conveying capacity of the suction pump is mainly supplied for discharging the excavated soil, and the liquid that simply functions as a conveying medium can be reduced to the necessary minimum in detail.

[0014] By further returning a split flow of the sucked liquid containing the excavated soil directly to the machine frame, the amount of work to be supplied by the suction pump, which must be supplied for discharging the remaining split flow upward, can be reduced. In this way, even if the suction capacity of the suction pump is limited, an efficient operation with a high excavation speed and a large total amount of excavated soil can be achieved.

[0015] The return line has the function of introducing the liquid split by the filter, which can be referred to as a suspension, again to the frame at a suitable location in the trench. The outflow of the split liquid containing a smaller amount of excavated soil can occur preferably at a suitable location above the cutting wheel, preferably substantially without pressure.

[0016] By appropriately designing a filter having a filter opening, the size of the filter opening can be adjusted in a predetermined manner to the minimum or maximum size at which the excavated soil is discharged upward. Specifically, in this way, it is also possible to set up to what size smaller soil pieces can be returned by the return line and remain in the suspension and in the trench in the ground.

[0017] In principle, only smaller soil can be discharged upward, and coarser soil pieces are fed back to the cutting wheel and further pulverized. This also reduces the treatment of the suspension at the ground surface.

[0018] According to a further development of the invention, it is particularly preferred that the filter is arranged and configured to pass a liquid containing smaller excavated soil through the return line, wherein larger soil pieces that cannot pass through the filter can be discharged upward via the discharge line together with the liquid. One concept is to provide a return line having a filter on the machine frame, preferably above the suction pump, and this filter allows a liquid containing excavated soil smaller than a certain degree to pass through, while larger soil pieces can be further discharged upward out of the hole in the ground via the discharge line. Thus, by arranging the filter, the so-called increasing density of the soil in the suspension to be discharged upward is achieved. In this way, the conveying capacity of the suction pump is mainly supplied for discharging the excavated soil, and the liquid that simply functions as a conveying medium can be reduced to the necessary minimum in detail.

[0019] A preferred embodiment of the present invention consists in that a regulating unit, in particular a throttle or a control valve, is arranged in the feedback line and is configured to regulate the flow through the feedback line. The regulating unit may in principle be any suitable member for setting and changing the flow rate passing through the feedback line, but in that case the flow rate also changes accordingly in the further upward part of the discharge line. The regulating unit may preferably be a throttle, i.e. a constriction in the feedback line, or a control valve, for example a butterfly valve or a valve with an adjustable slide. For this purpose, the regulating unit may be adjustable manually or remotely by a control device. In addition, automatic control depending on the output of the suction pump and / or the working depth can be provided. In particular, as the working depth increases and thus the work of the pump for discharging the excavated soil upwards increases, the regulating unit can be changed to increase the diversion in the feedback line. The diversion to be pumped upwards thus decreases accordingly, so that the cut soil can be pumped upwards sufficiently even if the conveying height increases.

[0020] According to a variant of an embodiment of the present invention, it is particularly advantageous if a servo motor for adjusting the control valve is arranged on the machine frame. The servo motor may be an electric or hydraulic motor or an actuator operating with hydraulic or pneumatic pressure. In principle, the diversion unit can be configured such that if the output present during operation of the suction pump is sufficient, no liquid flow is introduced into the feedback line at all.

[0021] In particular, an advantageous embodiment of the present invention consists in that the feedback line is configured to be telescopic. In this way, the feedback line can be pushed into a retracted arrangement when not needed. This enables the feedback line, which may in particular have a telescopic end pipe section, to be moved to the desired outlet position. In particular, a diffuser can be provided at the outlet end of the feedback line so that the returned liquid flows out as gently as possible within the cutting groove.

[0022] According to a further configuration of the present invention, the flow splitting unit preferably comprises a housing in which an inlet opening for the suction line, an outlet opening for the discharge line, and an outlet opening for the return line are formed. In this case, the housing may surround an accommodation space in front of the outlet opening to the return line where a filter is arranged.

[0023] A particularly advantageous configuration of the construction machine according to the present invention is achieved in that a connecting part having filter openings for forming a filter is arranged in the housing of the flow splitting unit between the inlet opening of the suction line and the outlet opening of the discharge line.

[0024] In this case, it is particularly advantageous if the connecting part is configured as a tube in order to form a tubular filter. In this way, the sucked liquid can flow from the inlet opening to the outlet opening through the connecting unit in the tubular flow path. At this time, the liquid containing smaller soil to be returned can flow through the filter openings in the tubular filter into the adjacent accommodation space in the housing of the connecting unit, and can flow back from there through the return line.

[0025] A particularly preferred development of the present invention is achieved in that the filter in the housing of the flow splitting unit is surrounded by an accommodation space, where the liquid can enter the accommodation space via the outer periphery of the filter, and the accommodation space is connected to the return line. In this case, the filter can be configured in particular as a tubular filter such that the liquid can pass through the entire outer periphery of the tubular filter into the surrounding accommodation space of the flow splitting unit. This enables the sucked liquid containing the excavated soil to be split and filtered particularly efficiently. The liquid containing the excavated soil may also be referred to as a suspension.

[0026] In order to operate reliably over a long period of time, according to one development form of the present invention, it is preferable that the filter be removably mounted within the housing of the shunt unit. Specifically, an opening and closing inlet for easy access to the filter can be provided in the housing of the shunt unit.

[0027] The filter can be easily removed by suitable releasable fastening means, and when the filter is worn, especially clogged, it can be easily removed, washed or replaced with another filter. In principle, a plurality of filters, or a plurality of filtering members that can be arranged, for example, in a stacked manner to form a complete filter in this way, can also be provided within the shunt unit.

[0028] According to one development form of the present invention, the construction machine is preferably configured as a trench cutting machine or an underground excavator. In the case of a trench cutting machine, one or preferably a plurality of cutting wheels are arranged, and the cutting wheels have a cutting wheel axis oriented horizontally or transversely with respect to the vertical travel direction. The trench cutting machine is preferably arranged at the lower end of the machine frame and has two pairs of cutting wheels that are rotationally driven to excavate the soil.

[0029] In the case of an underground excavator, the excavation head is arranged below the machine frame and is rotationally driven around a preferably vertical excavation axis oriented in the travel direction. The machine frame of the construction machine can also be provided with a guiding member for guiding the machine into the hole in the ground, and preferably a protruding member oriented transversely. The protruding member can fix at least a part of the construction machine to the hole wall to apply an additional driving force.

[0030] The present invention further includes a method of forming a hole in the ground, characterized in that a suction line leads to the shunt unit, the shunt unit is arranged on the machine frame, an upward discharge line and a return line through which a part of the sucked liquid is returned to the lower end region of the machine frame are connected to the shunt unit, and the shunt unit has a filter through which the liquid containing smaller excavated soil passes through the return line or the discharge line.

[0031] Specifically, the method according to the present invention can be carried out by one of the above-described construction machines according to the present invention. In this case, the above-described advantages can be achieved.

Brief Description of the Drawings

[0032]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0033] The present invention will be described in more detail below with reference to the preferred exemplary embodiments schematically shown in the drawings.

[0034] An exemplary embodiment of a construction machine 10 according to the present invention, which is configured as an in-pit excavator 11, can be seen in FIGS. 1 and 2. The schematically shown holding device 14 is arranged in the upper end region on the elongated machine frame 12. The holding device 14 is configured to attach and hold the construction machine 10 to a support cable or support rod, and may include, for example, a hook receptacle.

[0035] At the lower end of the machine frame 12, a rotatably drivable excavation member 22 as an excavation device 20 is arranged, which may be an excavation head 23 having excavation teeth 24 according to the illustrated exemplary embodiment. The excavation head 23 can be rotationally driven around an excavation axis, which is normally vertical, via a tubular excavation drive cable 18 by a plurality of drive units 16 in the central region of the machine frame 12. The excavation cable 18 can be axially moved relative to the machine frame 12 in a generally known manner for performing the excavation process by a feed cylinder 26. The tensioning member 28, which is schematically illustrated, can extend radially to fix the construction machine 10 against the wall of the ground hole and can be arranged on the machine frame 12.

[0036] During excavation, the excavated soil is sucked by a suction device 30 in the excavation head 23 together with the surrounding liquid supplied to support the excavation hole. A suction opening (not shown in detail), through which the excavated soil together with the liquid can be pumped upward by a suction line 32 and a suction pump 34, can be arranged in the excavation head 23.

[0037] In the above case, the suction line 32 preferably reaches a flow splitting unit 40 having a box-shaped housing 42, as shown in detail in FIG. 2. On the lower side of the housing 42 of the flow splitting unit 40, there is an inflow opening 43 for the suction line 32. Also, on the lower side of the housing 42, an outflow opening 45 for a return line 60, which will be described in more detail below, is configured. A control valve 70 having a servo motor 72 can be arranged in the return line 60 to adjust the splitting of the liquid to be returned.

[0038] Furthermore, an outflow opening 44 for a discharge line 38 is formed on the upper side of the housing 42. The discharge line 38 extends upward from the ground hole to discharge the excavated soil and liquid out of the hole and, in particular, to supply them to a treatment plant to separate the liquid from the excavated soil.

[0039] As can be clearly seen from FIGS. 3 and 4, the accommodation space 46 is surrounded by the housing 42 of the flow splitting unit 40. A filter 50 is disposed inside the accommodation space 46, and in the illustrated exemplary embodiment, the filter 50 is preferably configured as a tubular connecting component 52 that connects the inflow opening 43 of the suction line 32 to the outflow opening 44 of the discharge line 38. A plurality of filter openings having a predetermined opening diameter are provided in the tubular connecting component 52 to form the filter 50.

[0040] In this way, the liquid containing the excavated soil, which is sucked by the suction pump 34, can flow into the flow splitting unit 40 through the inflow opening 43, enter the discharge line 38 through the outflow opening 44, and then be discharged upward. Due to the openings of the filter 50, a part of the sucked liquid can enter the surrounding accommodation space 46 of the housing 42 of the flow splitting unit 40 together with the smaller soil pieces of the cut soil that can pass through the openings of the filter 50. This split flow with the filtered liquid enters the return line 60 through the outflow opening 45 and can return to the lower region of the machine frame 12 through this line. The return line 60 can be configured telescopically with a sliding telescopic section 64. In this case, the telescopic section 64 has an opening 62 above the excavation head 23 and can follow the axially sliding excavation head 23. In this way, the filtered liquid containing a part of the excavated soil with a smaller piece size can remain in the hole in the ground and does not need to be discharged upward.

[0041] As a result, the amount of the split flow of the liquid that needs to be discharged upward through the discharge line 38 by the suction pump 34 is reduced. In addition, the flow splitting unit 40 having the filter 50 provided according to the present invention increases the density of the excavated soil having larger pieces to a certain extent, whereby it is possible to achieve limiting the output of the pump in order to efficiently discharge most of the excavated soil.

Claims

1. An earthmoving machine for forming a hole in the ground, comprising: - a machine frame (12); - a holding device (14) in an upper region of the machine frame (12) for attaching and holding the earthmoving machine (10) to a support cable or support rod; - an excavation device (20) having at least one rotatable excavation member (22), disposed in a lower end region of the machine frame (12) and configured to excavate soil; - a drive unit (16) disposed on the machine frame (12) for rotationally driving at least one of the excavation members (22); - a suction device for suctioning excavated soil upward together with a liquid contained in the hole via a suction line (32), the suction device comprising at least one suction opening in the lower end region of the machine frame (12) and a suction pump (34) disposed on the machine frame (12); - in an earthmoving machine in which the suction line (32) reaches a flow splitting unit (40), the flow splitting unit (40) is disposed on the machine frame (12), and an upward discharge line (38) and a return line (60) for returning a part of the suctioned liquid to the lower end region of the machine frame (12) are connected to the flow splitting unit (40), - the flow splitting unit (40) has a filter (50) configured to pass a liquid containing smaller excavated soil through the return line (60) or the discharge line (38); - the filter (50) is configured to pass a first split of the liquid containing smaller excavated soil through the return line (60), wherein larger soil pieces that cannot pass through the filter (50) can be discharged upward through the discharge line (38) by the suction pump (34) in a second split together with the liquid. An earthmoving machine characterized by the above.

2. The earthmoving machine according to claim 1, A regulating unit (70), in particular a throttle or a control valve, is arranged in the feedback line (60) and is configured to regulate the flow passing through the feedback line (60). A construction machine characterized by the above.

3. The construction machine according to claim 1 or 2, wherein the feedback line (60) is configured to be telescopic. A construction machine characterized by the above.

4. The construction machine according to any one of claims 1 to 3, wherein the diversion unit (40) includes a housing (42) in which an inflow opening (43) for the suction line (32), a first outflow opening (44) for the discharge line (38), and a second outflow opening (45) for the feedback line (60) are formed. A construction machine characterized by the above.

5. The construction machine according to claim 4, wherein a connecting component (52) having a filter opening is disposed in the housing (42) of the diversion unit (40) between the inflow opening (43) of the suction line (32) and the first outflow opening (44) of the discharge line (38) to form a filter (50). A construction machine characterized by the above.

6. The construction machine according to claim 5, wherein the connecting component (52) is configured as a pipe to form a tubular filter (50). A construction machine characterized by the above.

7. The construction machine according to any one of claims 1 to 6, wherein the filter (50) in the housing (42) of the diversion unit (40) is surrounded by an accommodation space (46), and in this case, liquid can enter the accommodation space (46) through the outer periphery of the filter (50). The accommodation space (46) is connected to the return line (60). A construction machine characterized by this.

8. A construction machine according to any one of claims 1 to 7, The filter (50) is detachably mounted in the housing (42) of the flow dividing unit (40). A construction machine characterized by this.

9. A construction machine according to any one of claims 1 to 8, The machine is configured as a trench cutter or an underground excavator (11). A construction machine characterized by this.

10. In particular, a method of forming a hole in the ground with a construction machine (10) according to any one of claims 1 to 9, wherein the construction machine (10) comprises: - A machine frame (12); - A holding device (14) in the upper region of the machine frame (12), the holding device (14) by which the construction machine (10) is attached to and held by a support cable or a support rod; - An excavation device (20) having at least one rotatable excavation member (22), the excavation device (20) being arranged in the lower end region of the machine frame (12), wherein soil is excavated by at least one of the excavation members (22) to form the hole in the ground; - A drive unit (16) arranged on the machine frame (12), the drive unit (16) for rotationally driving at least one of the excavation members (22); - A suction device through which excavated soil is suctioned upward together with the liquid contained in the hole, the suction device comprising at least one suction opening in the lower end region of the machine frame (12) and a suction pump (34) arranged on the machine frame (12); - In a method in which the suction line (32) reaches up to a flow splitting unit (40) which is arranged on the machine frame (12), and an upward discharge line (38) and a return line (60) through which a part of the sucked liquid is returned to the lower end region of the machine frame (12) are connected to the flow splitting unit (40), - the flow splitting unit (40) has a filter (50) through which the liquid containing smaller excavated soil passes into the return line (60) or the discharge line (38), - the filter (50) is configured to pass a first split of the liquid containing smaller excavated soil into the return line (60), wherein larger soil pieces which cannot pass through the filter (50) are discharged upward via the discharge line (38) by the suction pump (34) in a second split together with the liquid, which is characterized by the above.

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