Grate rake for cleaning a grate arranged in a water conduit

Claim 1

A GRATE RAKE FOR CLEANING A GRATE ARRANGED IN A WATER CONDUIT, INCLUDING A RAKE HANDLE, A RAKE COMB, MEANS PIVOTALLY CONNECTING SAID COMB TO SAD HANDLE, MEANS FOR MOVING SAD COMB FROM A POSITION OF REST ABOVE THE WATER SURFACE LEVEL INTO AN INITIAL WORKING POSITION AT THE LOWER END OF SAID GRATE AND FROM THIS POSITION ALONG A WORKING TRAVEL WITH ITS TEETH ENGAGING THROUGH BETWEEN THE GRATE BARS AND COLLECTING THE ACCUMULATED OVERSIZE MATERIAL ON THE GRATE, UPWARD INTO AN EMPTYING POSITION AND BACK AGAIN, SAID RAKE HANDLE, IN THE POSITION OF REST OF THE SAID RAKE COMB, OCCUPYING AN INITIAL POSITION WHICH IS INCLINED OPPOSITELY TO THE DIRECTION OF FLOW OF THE WATER SLIGHHTLY DOWNWARD AND FORWARD TOWARD THE BARS OF THHE GRATE, AND MEANS TO CARRY OUT THE MOVEMENTS OF THE RAKE COMB COMPRISING A CRANK ARM, MEANS CONNECTING ONE END OF SAID CRANK ARM TO SAID HANDLE AT THE END OF THE LATTER REMOTE FROM SAID COMB BY AN ARTICULATION CONTAINING A HORIZONTAL PIVOTING AXIS, STATIONARY MEANS PIVOTING THE OTHER END OF SAID CRANK ARM ABOUT A HORIZONTAL AXIS BEHIND THE GRATE, A FIRST DOUBLE-ACTING CYLINDER AND PISTON UNIT PIVOTED AT ONE END TO SAID CRANK ARM, A SECOND STATIONARY PIVOT MEANS, MEANS CONNECTING THE OTHER END OF SAID FIRST CYLINDER AND PISTON UNIT TO SAID SECOND STATIONARY PIVOT MEANS, A SECOND DOUBLE-ACTING CYLINDER AND PISTON UNIT, MEANS PIVOTABLY ATTACHING SAI SECOND CYLINDER AND PISTON UNIT AT THE REAR END OF THE RAKE HANDLE AT A POINT SPACED FROM THE ARTICULATION BETWEEN THE CRANK ARM AND THE RAKE HANDLE, AND A RAKE COMB GUIDE ARRANGED PARALLEL TO THE SAID GRATE BARS AND EXTENDING UPWARDLY APPROXIMATELY TO THE LEVEL OF THE RAKE COMB EMPTYING POSITION.