Lever-operated shears

A lever-operated shears comprising a frame, a first jaw integral with the frame and carrying a first cutting blade, a second jaw pivotable relative to the first jaw and carrying a second cutting blade, an operating lever pivotally connected to the frame by a first pivot pin, a link for pivotally connecting said lever to said second jaw, said link being located beyond said first pivot pin with respect to said connection of said second jaw on said first jaw, said lever having a rest position, said shears further comprising a device for authomatically returning said lever to and maintaining it in said rest position, said device comprising a first member pivotally connected to said frame by means of a second pivot pin, a second member pivotally connected to said lever by means of a third pivot pin and slidably mounted through said first member on one hand and in the plane thereof, in a direction perpendicular to said second pivot pin on the other hand, said first, second and third pivot pins being parallel one to another, a first elastically yieldable means having a rotary action, and mounted between the frame and said first member, and a second elastically yieldable means having a rectilinear action and mounted on said second member between one end thereof and said first member, said first and second elastically yieldable means being capable of acting in a direction for biasing the lever to its rest position.