Advancing system for coal winning machine

Advancing system for moving a coal-winning machine along a face conveyor, comprising:

• a coal-winning machine located on
• a face conveyor having end heads;
• a guide secured between the end heads adjacent the face conveyor and having rack-type engagement elements arranged throughout its length;
• the advancing system having
• a housing separate from said coal-winning machine whereby the advancing system can be used with selected winning machines, the housing being installed on the guide
• and being connected with the coal-winning machine by lateral connector means for transmitting advancing forces from the housing to the winning machine;
• at least two slides installed in said separate housing and interacting with said guide;
• at least two hydraulic cylinders successively interconnected with each other, installed in said separate housing and hinged to the corresponding said slides for moving them along said guide;
• grips in the lower part of each of said slides for holding said slides on said guide;
• fixing bars mounted in each of said slides and adapted for interaction with the engagement elements of said guide;
• at least two hydraulic cylinders, each rigidly connected with a corresponding said slide and interacting with a corresponding said fixing bar so that each of said fixing bar interacts alternatively with the engagement elements of said guide for moving the coal winning machine over said guide.