A ground breaking machine has a housing and the housing has oppositely disposed end plates which have aligned axial female openings and matching male plate portions positioned in the female openings. The female opening is defined by a side edge having top and oppositely disposed vertical spaced apart side edge portions. Each of the vertical side edge portions terminate in a laterally inwardly extending portion having an upperwardly extending hook portion engageable with a downwardly extending hook portion on the male plate portion for interlocking the female and male hook portions to prevent separation thereof and separation of the male plate portion in the female opening.

The method of assembly and mounting the cutter drum in the housing includes the steps of providing a housing having oppositely disposed end plates including aligned axial openings and matching male plate portions for being positioned in the female openings. The cutter drum has a gear drive mounted in an end of the cutter drum and is provided with a hydraulic motor on one of the male plate portions. The cutter drum is positioned under the housing and the male plate portion having the hydraulic motor is positioned in the female opening in an end plate. The hydraulic motor on the male plate portion is connected to the gear drive in the end of the cutter drum.

In such fields as road milling, mining and trenching it is often desirable to engage and degrade tough materials such as asphalt, concrete and rock. To do so, degradation picks comprising hardened tips may be secured to an exterior of a rotatable drum so as to be repeatedly brought into contact with a surface of a material to be degraded. To secure such degradation picks to the rotatable drum, a toroidal body comprising an interior surface rigidly attachable to the rotatable body and an exterior surface comprising a plurality of bore holes disposed there around may receive a plurality of degradation picks secured within the bore holes.

In such fields as road milling, mining and trenching it is often desirable to engage and degrade tough materials such as asphalt, concrete and rock. To do so, degradation picks comprising hardened tips may be secured to an exterior of a rotatable drum so as to be repeatedly brought into contact with a surface of a material to be degraded. To secure such degradation picks to the rotatable drum, a toroidal body comprising an interior surface rigidly attachable to the rotatable body and an exterior surface comprising a plurality of bore holes disposed there around may receive a plurality of degradation picks secured within the bore holes.

In a drum housing for a working drum of a construction machine or mining machine, said working drum being provided with tools and rotating about a drum axis, with a housing shell which at least partially encloses the circumference of the working drum, and with at least one inspection opening for a monitoring device arranged in the housing shell, wherein said monitoring device inspects the condition of the working drum or the tools thereof, it is provided for the following features to be achieved: a closing mechanism is arranged on the outside of the housing shell, said closing mechanism enabling closure of the at least one inspection opening.

In a drum housing for a working drum of a construction machine or mining machine, said working drum being provided with tools and rotating about a drum axis, with a housing shell which at least partially encloses the circumference of the working drum, and with at least one inspection opening for a monitoring device arranged in the housing shell, wherein said monitoring device inspects the condition of the working drum or the tools thereof, it is provided for the following features to be achieved: a closing mechanism is arranged on the outside of the housing shell, said closing mechanism enabling closure of the at least one inspection opening.

The invention relates to a bit holder for an earth working machine, in particular a surface miner, a road milling machine, or the like, having a holding projection that comprises a bit receptacle and/or carries a cutting element. In order to improve the operating reliability of an earth working machine, provision is made according to the present invention that the holding projection has, behind the cutting element or behind a receiving region of the bit receptacle in the tool advance direction, a wear protection element having a hard-material element in order to provide an emergency-mode property.

The invention relates to a bit holder for an earth working machine, in particular a surface miner, a road milling machine, or the like, having a holding projection that comprises a bit receptacle and/or carries a cutting element. In order to improve the operating reliability of an earth working machine, provision is made according to the present invention that the holding projection has, behind the cutting element or behind a receiving region of the bit receptacle in the tool advance direction, a wear protection element having a hard-material element in order to provide an emergency-mode property.

Systems and methods are provided for detecting face alignment and face steering of a longwall mining system. The system includes a detection device mounted in a maingate roadway and a first indicator device mounted on a shearer of the longwall mining system to indicate a position of the shearer to the detection device. The system further includes a controller coupled to the detection device. The controller determines a shearer path of the shearer as the shearer moves along an ore face. The shearer path is determined based on a signal from the first indicator device received by the detection device. The controller generates an indication of face alignment based on the shearer path.

Systems and methods are provided for detecting face alignment and face steering of a longwall mining system. The system includes a detection device mounted in a maingate roadway and a first indicator device mounted on a shearer of the longwall mining system to indicate a position of the shearer to the detection device. The system further includes a controller coupled to the detection device. The controller determines a shearer path of the shearer as the shearer moves along an ore face. The shearer path is determined based on a signal from the first indicator device received by the detection device. The controller generates an indication of face alignment based on the shearer path.

The invention relates to a milling machine having a replaceable milling drum, different types of milling drums being capable of being associated with the milling machine; and having a control unit for controlling the milling machine, machine parameters of the milling machine being settable by way of the control unit. Provision is made that the milling machine has associated with it at least one means that is designed to detect at least one characteristic feature of the milling drum; that the at least one means is connected to the control unit; and that the control unit is designed to specify for at least one machine parameter, indirectly or directly from the characteristic feature, a value to be set, and/or a setting range. The invention further relates to a corresponding milling drum and to a corresponding method. The milling machine, milling drum, and method allow the selection of machine parameters for operation of the milling machine to be simplified.