The invention relates to an earth working apparatus having an undercarriage which is designed as a running gear, and an upper carriage which is supported in a rotatable manner on the undercarriage and has a driver's cab as well as a drive motor for the undercarriage. According to the invention, between the undercarriage and the upper carriage an extension segment is arranged, through which a vertical distance between the undercarriage and the upper carriage is extended. On the extension segment between the undercarriage and the upper carriage a support means for tilt protection is mounted. The invention furthermore relates to a method for earth working with an earth working apparatus of such type.

The present invention relates to a special civil engineering machine, in particular a slurry wall cutter, comprising at least one rotating tool and a tool drive that is arranged within a housing of the special civil engineering machine and is sealed with respect to the environment by means of at least one bearing seal in the region of its shaft exit from the housing to the driven tool, characterized in that the bearing seal comprises at least two separate sealing elements, whose arrangement forms a sealing chamber located between the sealing elements, wherein a pressure compensation device is provided, which controls the chamber pressure in the sealing chamber in dependence on the ambient pressure of the special civil engineering machine.

The present invention relates to a drive device for a diaphragm wall cutter (1), having a drive housing and/or gear housing (11), which encloses an interior (16) for accommodating drive and/or gear elements and comprises two housing parts (13, 14) which are rotatable relative to one another and which are sealed with respect to one another by a sealing device (15), and having a pressure equalization device (19) for pressure equalization between the interior and the surroundings. The invention also relates to a diaphragm wall cutter having such a drive device. It is proposed here not to pressurize the entire interior of the housing, but only an interspace (20) arranged upstream with respect to the surroundings, and to seal said interspace with respect to the interior on the one hand and with respect to the surroundings on the other hand. According to the invention, the pressure equalization device comprises at least one intermediate chamber (20), which is pressurized by a pressure source and is sealed with respect to the interior by an inner seal (21) and with respect to the surroundings by an outer seal (22). By virtue of such a sealed intermediate chamber between the housing interior and the surroundings that can be considerably smaller in terms of volume than the interior, the pressurization for pressure equalization between interior and surroundings is considerably simpler.

A roadway access hole drill for cutting a square or rectangular access hole in a roadway having a first saw opposing a second saw and a third saw opposing a fourth saw. A method of cutting a microtrench in which the buried utility is exposed by opening a square or rectangular access hole in a roadway above the buried utility using the roadway access hole drill that is controlled by a computer system connected to an under-roadway detection unit that detects a buried utility and stops movement of the drill to avoid damaging the buried utility.

A road working machine includes an operator's station that is adapted to be occupied by an operator of the road working machine. The road working machine also includes a controller and a safety light circuit that is operatively attached to the controller. The safety light circuit includes a plurality of downwardly directed safety lights that are located so as to provide lighted egress from the operator's station.

The invention relates to a foundation engineering machine and a method for producing a trench in the ground with a foundation engineering machine having a substantially vertical mast, a diaphragm wall apparatus which is displaceably supported in the longitudinal direction of the mast for producing a trench in the ground, and a bar-shaped holding means, at the lower end of which the diaphragm wall apparatus is mounted and with which the diaphragm wall apparatus is linearly displaceable along the mast. According to the invention provision is made in that on the mast an upper first clamping sledge with a first clamping means for releasably clamping the bar-shaped holding means and a lower second clamping sledge with a second clamping means for releasably clamping the bar-shaped holding means are movably supported and the first clamping sledge and the second clamping sledge are movable relative to each other and in that the lower second clamping sledge is provided with a connecting means for mounting an additional lifting device which is arranged on the ground and with which a force can be applied in the longitudinal direction onto the second sledge.

The invention relates to a drive device for a construction machine, in particular for a trench cutter, comprising a connection support and a wheel support, which is rotatably supported on the connection support via at least one rolling bearing and which can be rotationally driven relative to the connection support by a drive motor via at least one gear stage, wherein the gear wheel of the gear stage, said wheel being arranged within the connection support and meshing or being in rolling engagement with at least one other gear wheel, is movably and/or tiltably supported in the radial direction relative to the connection support by a flexible and/or movable bearing element so as to be rotationally fixed to the connection support and/or to a bearing shield rigidly connected thereto.

A roller tool for a soil cultivation roller of a soil cultivation machine includes a tool carrier to be fixed on an outer circumferential side of a carrier cladding of a soil cultivation roller, a quick-change tool holder to be detachably fixed on the tool carrier, and an exchangeable tool to be detachably fixed on the quick-change tool holder.

A method of cutting a microtrench in which the buried utility is exposed by opening an access hole in a roadway above the buried utility using a roadway access hole drill that is controlled by a computer system connected to an under-roadway detection unit that detects a buried utility and stops movement of the drill to avoid damaging the buried utility. Also provided is a method of drilling a substantially horizontal hole under a roadway using a horizontal drill that is controlled by a computer system connected to an under-roadway detection unit that detects a buried utility and stops movement or changes direction of the drill to avoid damaging the buried utility.

The invention relates to a trench wall cutting device, to a trench cutter having a trench wall cutting device according to the invention, and to a method for cutting a cut trench using a trench cutter, which is constructed from at least two cutter modules, and at least one supply unit, which is connected to the cutter modules by means of cables. The first cutter module can be lowered into a guide trench before the second cutter module is placed onto the first cutter module. As a result, a cut trench can be created at a location with a restricted height, wherein in the trench the cutter has a guide height that is greater than the height of the site out of which the cut trench is generated.