Hermann Hemscheidt Maschinenfabrik Gmbh & Co.

Other

Hermann Hemscheidt Maschinenfabrik Gmbh

Guy Geuns

Werner Reinelt

Josef Welzel

Karl Krieger, Deceased

By Hildegard Krieger, Legal Representative

Otmar Pfeiffer

In a method of mining coal seams using a ploughing cutter, a longwall conveyor extending along the coal face is moved forwards by the extension of self-advancing cylinders, the advance being controlled in dependence on a piston stroke of a respective self-advancing cylinder and being made in individual defined partial strokes using travel-measuring signals generated at each partial stroke. The distance covered by the partial strokes corresponds to the preset depth of cutting and is increased by an amount sufficient to compensate an average mechanical clearance at the pivot points of the self-advancing cylinders. In addition, a defined face line is fixed with respect to a center of rotation on the side of a main or auxiliary drive of the cutter so as to form a straight line through the center of rotation, the straight line being pivoted through an angle &lt;90.degree. so that a circular segment is mined.

Method of mining coal seams at a defined preset depth of cutting during

A method of working coal seams to a defined preset cutting depth during ploughing with a cutter, a face conveyor moving along a face behind the cutter being advanced by the defined preset cutting depth and this advance being made by extension of self-advancing cylinders pivotally attached at one end to the face conveyor and at the other end to face supports disposed parallel to the face conveyor. The advance is controlled in dependence upon the piston stroke of the self-advancing cylinders, carried out in dependence upon individually defined partial strokes corresponding to the preset depth of cutting. After a predetermined maximum total piston stroke has been reached, the face support connected to the respective self-advancing cylinder is automatically disengaged, advanced by the maximum total piston stroke and then re-set (self-advancing process). The length of the partial strokes corresponding to the preset depth of cutting is increased by an amount to compensate an average mechanical clearance at the pivot points of the self-advancing cylinders.

Method of working coal seams to a defined preset depth of cutting during

A control system for longwall face support frames as used in mines, the system comprising pushing rams which are adapted to be actuated at two different pressures (for example, a low pressure of about 70 to 120 bar for non-defined cutting and a high pressure of 120 to 350 bar for defined cutting) with each pushing ram being individually actuatable by a respective non-return valve arrangement, the pushing rams being connected by a common pressure line to an hydraulic pressure unit.

Control system for longwall face support frames

An intrinsically safe power supply unit, more particularly for face supports in mining, comprising an ac transformer connected to a rectifier and power resistors for limiting the current and connected to the dc voltage output, wherein the ac voltage transformer is a resonance transformer which stabilizes the secondary voltage, and the dc voltage occurring behind the power resistors is kept constant by three voltage limiters connected in parallel.

Intrinsically safe power supply unit

A multipole connector in the form of a sealed lead-through for fitting through a wall of a casing of a control device used for underground working, comprising a contact-holder secured via securing parts in sealing-tight manner in an opening in the wall and having a number of contact chambers extending through the contact holder parallel to one another in the direction of the longitudinal axis of the connector, each contact chamber containing contact elements which have connecting pieces which project outwards from one side of the contact holder for the purpose of making connections, characterized in that the connecting pieces of the contact elements comprise parallel soldering taps.

Multipole connector for control devices in underground working

The invention relates to a method and system for supplying devices which are charged with a fluid pressure medium as a working medium with electrical energy for actuating electrical parts of the device, wherein an energy converter is subjected to the fluid pressure medium in such a way that a fraction of the energy of the fluid pressure medium is converted into electrical energy which is then stored in an electric store.

Growing community of inventors

Wuppertal, Germany

Guy Geuns