Abstract: A device for connecting a back rest to the seating portion support mechanism for chairs includes a first part pertaining to the mechanism, a second part pertaining to the back rest, a pair of pins, at least one of which is applied to the first part (second part), a pair of open slots, at least one of which pertains to the second part (first part), the slots forming housings for the pins, an elastic member acting on at least one of the pins or the housings, the distance between the axes of the pins or the housings being modifiable temporarily against the action of the elastic member, wherein the open slots present an inclined surface which, by acting against one of the pins, causes a temporary modification of the distance between axes of the pins, so facilitating engagement of the pin in the housing seat.

Abstract: An armrest, in particular for office chairs, comprising a support bracket (16) connected to the chair, a tube (34) connected to the vertical part (24) of said bracket, and an arm support pad, characterized in that the tube presents at one end a flange (36) comprising rotation guides for a plate (66), said plate presenting an aperture (66) for the insertion of the lower end of the tube and being provided with rotation guides (38) cooperating with said flange (36) for the rotation of said plate (66) about said tube (34), said plate (66) and said pad (80) being constrained by mutually cooperating slide guides (74, 78) which enable said pad (80) to translate relative to said plate (66) with said flange (36) interposed between them.

Abstract: A device for connecting a back rest to the seating portion support mechanism for chairs includes a first part pertaining to the mechanism, a second part pertaining to the back rest, a pair of pins, at least one of which is applied to the first part (second part), a pair of open slots, at least one of which pertains to the second part (first part), the slots forming housings for the pins, an elastic member acting on at least one of the pins or the housings, the distance between the axes of the pins or the housings being modifiable temporarily against the action of the elastic member, wherein the open slots present an inclined surface which, by acting against one of the pins, causes a temporary modification of the distance between axes of the pins, so facilitating engagement of the pin in the housing seat.

Abstract: A method of forming a connecting structure between column and seating portion of an office chair includes the steps of forming a frusto-conical portion having a flange by cold-pressing a portion of sheet metal, inserting the flanged portion into a mold reproducing the shape of the structure, injecting plastic material into the mold and incorporating the flanged portion of the frusto-conical portion into the plastic material.

Abstract: An office chair mechanism provided with a device for adjusting the swivel force includes a fixed part secured to the chair base, movable parts secured to the seating portion and to the back rest (22) of the chair, and an elastic element which opposes the weight of the chair user, a lever having contact surfaces which interact with said fixed part by means of a fulcrum having a movable contact element interposed between the end acting on the elastic element and the other end to which the movable parts are pivoted, and an adjustment element which causes only the movable contact element to move but without modifying the position of the elastic element and of the lever.

Abstract: An armrest, in particular for office chairs, comprising a support bracket (16) connected to the chair, a tube (34) connected to the vertical part (24) of said bracket, and an arm support pad, characterised in that the tube presents at one end a flange (36) comprising rotation guides for a plate (66), said plate presenting an aperture (66) for the insertion of the lower end of the tube and being provided with rotation guides (38) cooperating with said flange (36) for the rotation of said plate (66) about said tube (34), said plate (66) and said pad (80) being constrained by mutually cooperating slide guides (74, 78) which enable said pad (80) to translate relative to said plate (66) with said flange (36) interposed between them.

Abstract: A method of forming a connecting structure between column and seating portion of an office chair includes the steps of forming a frusto-conical portion having a flange by cold-pressing a portion of sheet metal, inserting the flanged portion into a mold reproducing the shape of the structure, injecting plastic material into the mold and incorporating the flanged portion of the frusto-conical portion into the plastic material.

Abstract: A system for adjusting the relative position between two furniture parts includes a first part provided on one side with at least two parallel guide surfaces at a prefixed distance X apart, a second part facing the first part, an eccentric multi-lobe cam, the continuous profile of which is composed of tangential curves disposed such as to form an odd number n of pairs of opposing arcs, each pair of arcs having the same center of curvature with the sum of the radii of curvature being equal to X, the cam being housed between said two parallel guides and being pivoted to said second part on the eccentric pin, and means for rotating the multi-lobe cam.

Abstract: An office chair mechanism provided with a device for adjusting the swivel force includes a fixed part secured to the chair base, movable parts secured to the seating portion and to the back rest (22) of the chair, and an elastic element which opposes the weight of the chair user, a lever having contact surfaces which interact with said fixed part by means of a fulcrum having a movable contact element interposed between the end acting on the elastic element and the other end to which the movable parts are pivoted, and an adjustment element which causes only the movable contact element to move but without modifying the position of the elastic element and of the lever.

Abstract: A method for forming connecting structures between the column and seating portion for office chairs, characterised by:-forming a frusto-conical portion (8) provided with a flange (24, 26, 28) by cold-pressing a portion of sheet metal,-inserting said flanged portion into a mould (32) reproducing the shape of the structure,-injecting plastic material into the mould in such a manner as to incorporate the flanged portion (24, 26, 28) of said frusto-conical portion (8) into the plastic material.

Abstract: A system for adjusting the relative position between two furniture parts includes a first part provided on one side with at least two parallel guide surfaces at a prefixed distance X apart, a second part facing the first part, an eccentric multi-lobe cam, the continuous profile of which is composed of tangential curves disposed such as to form an odd number n of pairs of opposing arcs, each pair of arcs having the same center of curvature with the sum of the radii of curvature being equal to X, the cam being housed between said two parallel guides and being pivoted to said second part on the eccentric pin, and means for rotating the multi-lobe cam.

Abstract: A device for adjusting the reclining force in office chair mechanisms comprising at least two mutually hinged parts and elastic means (16) which maintain said parts elastically spaced apart, said device being characterized by comprising:—at least two levers (7, 6), at least one of which interacts with said elastic means (16) and the other of which is connected to one of said hinged parts, said levers respectively interacting via at least one movable contact element (13) by way of contact surfaces,—means (9, 10, 14) for adjusting the position of said movable contact element (13) such as to modify the points at which said movable contact element bears on said contact surfaces and consequently such as to modify the lever arms.

Abstract: An armrest/backrest support bracket characterised by comprising: a support (4) provided in its lateral surface with a slot (14) and in its end surface with a hole which communicates with said slot, a blade (6) one end of which is insertable into said slot, locking means inserted into said hole and interacting with said support and with that blade part (6) housed in the slot.

Abstract: A device for adjusting the reclining force in office chair mechanisms comprising at least two mutually hinged parts and elastic means (16) which maintain said parts elastically spaced apart, said device being characterised by comprising:—at least two levers (7, 6), at least one of which interacts with said elastic means (16) and the other of which is connected to one of said hinged parts, said levers respectively interacting via at least one movable contact element (13) by way of contact surfaces,—means (9, 10, 14) for adjusting the position of said movable contact element (13) such as to modify the points at which said movable contact element bears on said contact surfaces and consequently such as to modify the lever arms.

Abstract: A method for forming rotatable bases for offices chairs characterised by structurally joining together at least two half-shells to form overall a plurality of spokes, each consisting of an elongated box-shaped body, and a central ring into which a column is inserted.

Abstract: A height adjustment device, in particular for seat back portions and arm-rests in office chairs, comprising a guide element (14, 48) rigid with the support plate (10) for the seating portion (12), a slide (22, 42) supporting the movable part (18, 20) and engagable with and slidable along said guide element, and means (38) selectively engagable in one of a plurality of teeth (31) to provide a configuration of stability, said selectively engagable means sliding freely along the passive flanks of the teeth of the toothed portion during the raising of the movable part, and lockable by the active flanks each time a tooth is passed over, said selectively engagable means being disengagable, for a predetermined position of said slide (22, 42) relative to said guide element (14, 48), from said teeth thus enabling said slide to move by gravity along said guide element, characterized in that said toothed portion (28) is faced by a toothed counter-portion (32) the teeth (34) of which form with the teeth (31) of said toot

Abstract: A device for adjusting the height of a back-rest of a seat back portion, in particular in office chairs, comprising a guide element rigid with a support plate of a seating portion, a slide for supporting the back-rest, the slide being engagable with the guide element and slidable along it, and means which are elastically selectively engageable with a toothed portion to ensure the stability of the position of the slide relative to said guide.The elastic means are able to slide freely along the passive flanks of teeth of a toothed portion during the raising of the back rest, and are locked by the active flanks after each passage over a tooth.

Abstract: A device for adjusting the inclination of the seating portion in chairs in general, to be applied to a support for the seating portion formed in at least two parts (2, 12) hinged together about a transverse axis (14) and associated with a spring (20) interposed between them to elastically maintain the back rest of the chair in its most forwardly inclined position, and also associated with a locking member (24) to maintain them in other predetermined positions corresponding to different inclinations of the back rest, characterised by comprising: a locking bolt (26) forming part of the locking member (24) and fixed to one (2) of the two parts (2, 12) of the support for the seating portion, a plurality of holes (22) provided in the other part (12) of the support for the seating portion in positions engageable by the bolt (26) and corresponding to different relative inclinations between the two parts (2, 12) of the support, a rod (30) for axially operating the bolt (26), an axially bistable device (34) for contro

Abstract: A device for adjusting the inclination of the back-rest to the seating portion in chairs in general, comprising a first structural element rigid with the seating portion and a second structural element rigid with the back-rest and hinged to the first structural element on a transverse axis characterized in that with one of the two structural elements there is associated a first member provided with an inclined surface and rotating about an axis which intersects the transverse hinging axis, with the other of the two structural elements here being associated a second member maintained constantly in contact with the inclined surface for any angular position of the first member.