Soil loosening device

An apparatus which loosens soil as it moves along the surface of the earth, said apparatus comprising:

• a hollow supporting body including a casing with an upper casing plate, a lower casing plate, two longitudinal casing side walls and two transverse casing side walls;
• an even number of soil loosening tools rotatably mounted on said lower casing plate and protruding therefrom substantially perpendicularly, said loosening tools each comprising two tine-like tool members;
• driving means mounted on said upper casing plate for driving a first one or a first group of said soil loosening tools to an oscillating angular motion in a first direction and a second one or a second group of said soil loosening tools to an oscillating motion in a second direction opposite to said first direction to cause said tools to displace the soil;
• gearing means mounted in the interior of said hollow supporting body including first gear members drivingly connected to said driving means, second gear members drivingly connected to said soil loosening tools and transmitting means operatively connected to said first and said second gear members to transform a continuous rotary motion of said driving means into an oscillating angular motion of said soil loosening tools;
• handling means including a handle connected to said driving means for guiding and moving the apparatus over the surface of the soil to be loosened;
• said transmitting means including a toothed rack member slidingly received in said hollow supporting body and adapted to be driven to an oscillating motion, said rack member having a base portion which is provided with an elongate recess therein and having first and second driving legs extending perpendicularly to the axis of said elongate recess from said base portion and offset to each other in opposite directions, each of said first and second driving legs comprising at least one group of teeth arranged on oppositely directed edges thereof;
• said first gear members including a crank shaft operatively connected to said driving means and incorporating a crank pin which engages said elongate recess, the rotating crank shaft thereby driving said rack member to an oscillating motion;
• and
• said second gear members including gear wheels mounted on each of said soil loosening tools, said gear wheel of said first soil loosening tool or said gear wheels of said first group of soil loosening tools meshing with one of said teeth groups provided on said first driving leg and said gear wheel of said second soil loosening tool or said gear wheels of said second group of soil loosening tools meshing with the other one of said teeth groups provided on said second driving leg.