It is known to use a lifting mechanism to gain access to the underside of a lawnmower for purposes of cleaning or replacing the cutter blades.
These mechanisms most often have a tilting bearing structure that enables them to lift at least two wheels of the lawnmower. Two known types of tilting bearing structures are very widely used: structures with a single pivoting arm and parallelogram structures, constructed with two pivoting arms connected by a horizontal platform.
Thus for example, devices are known that are equipped with a lever, prolonged by a support arm, which is actuated and blocked in the raised position with the aid of an extension rod.
To raise the pivoting arm, it has also been suggested to use a jack formed by an endless screw that passes through a nut at the end of the arm and is operated by a crank or even a mechanical winch.
One drawback of these known devices is that they require physical strength to raise or tilt the lawnmower, particularly if the lawnmower is heavy. They are thus not suitable for use by those who are physically frail or weakened and/or if the lawnmower is heavy. More generally, they are awkward to use, and/or they are not of ergonomic design, which is unsatisfactory.
In order to limit the effort required on the part of the user, it has been suggested to use a cylinder to operate the device.
Document FR-A-2 873 107 describes such an example of the device, using a flexible cylinder or a piston rod cylinder which exerts a thrust under the pivoting arm of the chassis to cause it to tilt.
However, this device is associated with a number of disadvantages. It provides limited access to the underside of the lawnmower due to the presence of a cylinder. Moreover, a further disadvantage of this device consists in its residual vertical footprint after the pivoting arm has reached the limit stop against the body of the cylinder and has been lowered again.
A further disadvantage of this device is that it requires the use of specific cylinders, and for example a cylinder with a large rod or cylinder with a telescopic shaft.
Yet another disadvantage of this device is that it is possible for the user to cause the cylinder to retract inadvertently while working under the lawnmower, which is not acceptable from the point of view of safety.
USPTO Backgrounds
USPTO Backgrounds