Low-bed semi-trailer with attached jack and mat devices

Claim 1

A SEMI-TRAILER COMPRISING AN ELONGATED FRAME HAVING FRONT AND REAR PORTIONS SEPARATED BY A DEPRESSED CENTRAL PORTION, WHEELS SUPPORTING SAID REAR PORTION, MEANS CARRIED BY SAID FRONT PORTION FOR DETACHABLY CONNECTING THE TRAILER TO A TRACTOR THAT CAN HAUL THE TRAILER OVER THE GROUND, SAID CENTRAL PORTION OF THE FRAME BEING INCLINED FORWARD AND UPWARD FROM A POINT BELOW THE FRONT END OF SAID REAR PORTION WHILE THE TRAILER IS BEING HAULED, THE BOTTOM OF THE TRAILER AT SAID INCLINED CENTRAL PORTION HAVING A SUBSTANTIALLY FLAT BEARING SURFACE, LEGS PIVOTALLY SUSPENDED FROM THE REAR PORTION OF THE FRAME ON A TRANSVERSE AXIS AND SWINGABLE FROM A LOWER OPERATIVE POSITION UP TO AN INOPERATIVE POSITION, AND A MAT SECURED TO THE FREE ENDS OF THE LEGS AND HAVING A BEARING SURFACE ENGAGEABLE WITH THE GROUND ONLY WHEN LOWERED THERETO BY THE LEGS, THE PART OF SAID MAT BEARING SURFACE TO FIRST MAKE CONTACT WITH THE GROUND BEING DISPOSED AT AN ANGLE TO THE LEGS, THE REMAINING PART OF THAT SURFACE BEING FLAT AND SUBSTANTIALLY PERPENDICULAR TO THE LEGS, THE LEGS BEING LONG ENOUGH FOR ONLY THE ANGULAR PART OF THE MAT BEARING SURFACE TO ENGAGE THE GROUND WHEN THEY ARE SWUNG DOWN TO AN INCLINED POSITION SO THAT WHEN THE TRAILER IS MOVED LENGTHWISE A PREDETERMINED DISTANCE BY A TRACTOR TO MOVE ITS WHEELS TOWARD THE MAT THE REAR END OF THE TRAILER WILL BE RAISED BY THE LEGS AS THE UPPER ENDS OF THE LEGS ARE MOVED BY THE TRAILER AND ROCK THE MAT IN THE SAME DIRECTION, AND THE TRAILER BEING ADAPTED TO THEN BE ROCKED DOWN WHEN THE FRONT END OF THE TRAILER IS LOWERED AFTER BEING RELEASED FROM A TRACTOR, WHEREBY SAID TRAILER BEARING SURFACE WILL REST ON THE GROUND AND THE LOAD ON THE WHEELS WILL BE TRANSFERRED TO THE MAT.