Abstract: A fastening device to join together panels comprises a body (12) that has a spreader (32); a U-shaped spring (14) with arms (47, 48) provided with outward facing gripping portions (47", 48") protruding from the body and drawn together in a resting position; a cam-type operating element (18) rotatable in the body. By rotating the cam element, the spring is movable between a resting position with the arms close to each other, in which it leaves the panels free and an engagement position with the arms spread apart, in which it engages the walls of a hole in a panel, and vice versa. The body (12) has an elongated cylindrical shape and comprises an internal housing (26). A slide element (16) is received inside the housing, is moveable for an axial distance along it, and has a housing (44) for engaging the spring. The cam element (18) is received in the body and in the slide to operate the movement of the slide between the resting position of the spring and the working position of the spring and vice versa.

Abstract: A level adjustment device (10) comprises: a foot or base element (12) with a shaped part (20) and a threaded shank (24); a hollow, cylindrical operation or driving element, provided with female threaded parts and with a crown gear axially at one end; a support element (16) engaging in a stable manner the cylindrical operation element for axial movement and having an operation window (40).By introducing the tip of a cross-pointed screwdriver of an usual type through the operation window, the cylindrical hollow element is rotated, thus moving it and the support axially along the foot element.

Abstract: A fastening device including a housing element, a body rotatable for at least an arc in the housing element, and a resilient element located between the housing element and the body. The resilient element has arms movable between a disengagement position, at which the arms are near one another and extended, and an engagement position, at which the arms are moved away from one another and retracted for a traction engagement with the walls of an engagement hole. The body has cam parts for forcing the arms from the disengagement position to the engagement position, when the body is rotated.

Abstract: A clamping device for releasably snap joining or clamping two panels comprises a plug element and a bush element. The plug element comprises: a stem portion engageable with the walls of a hole in a panel; a body portion; a head portion formed with legs that can be resiliently moved near one another and defined by at least one longitudinal slit; a notch extended from the longitudinal slit within the body; and a slider slidable between the legs to lock the latter at widened out position.

Abstract: Device for the fastening of parts, panels and the like as separable from one another, comprising a cylindrical body which can be rotatably accommodated within a circular opening in one of the parts to be connected, and a pin secured to project from the other part, the pin having a shank formed with an end head defining a shoulder which cooperates with cam surfaces of the cylindrical body circumferentially extending from inside towards the side surface along the edges of at least one of a pair of opposing arcuate slits formed in opposite directions each from one end of a transverse hole for the pin passage.

Abstract: A device for rigidly interconnecting wood panels or other parts of a piece of furniture. The joint comprises a finned shank and a head, secured within a seat provided in a first panel, and the head being removably engageable with a pin projecting from a second panel to be connected to the former.The joint head comprises a seat coaxial with the shank, and open at the front and top for introducing the pin from above; on the bottom and at intermediate position, the seat in the joint head also has a transverse rib for engagement with a slot at the pin end. A closure cover clamps the pin in the seat and has projecting tabs for rotational engagement within longitudinal slots provided internally of the head at the top of the rib.