IMPROVEMENTS TO AN ARTICULATED FOLDING STRUCTURE FOR SOFA BED

Abstract: The improvements permit to convert a sofa having standard cross dimensions into a bed of ordinary length. The folding frame consists in an articulated structure formed by a fixed frame (1), a mobile frame (2), an intermediate frame (3), an auxiliary frame (4) and a further auxiliary frame (5) integral with two supporting legs (6), that acts as support of the stuffing of the back of the sofa or, alternatively, as prolongation of the bed. The blocking of the frame to define the sofa position is carried out by means of a hook (33) hinged in point (40) and by a pin (32) applied on the rod (22) that synchronize the movements of the structure.

Description: IMPROVEMENTS TO AN ARTICULATED FOLDING STRUCTURE FOR SOFA BED This invention deals with a sofa convertible into bed and more particularly the relative folding frame, with an articulated structure and synchronised movements. As it is known, sofas convertible into beds contain into their structure a metallic frame which has a articulated folding structure, including a fixed frame for the support to which are connected some mobile frames consecutively hinged between themselves. When they function as a sofa, the mobile frames are folded one on another and inserted inside of the support fixed frame; in order to form the bed, the mobile frames come out the fixed frame by a rotary and translatory movement until they line up between themselves. In the state of art. in order to increase the useful length of the bed without increasing the length of the fixed frame, the back is mounted directly on the most outward mobile frame instead of on the structure of the sofa. To the fixed frame is, on the contrary, associated a known type pantographic lever which causes the coming out of the frames themselves in order to bring them in a raised and leading position in relation to it. In the sofas having a folding and articulated structure, there are furthermore some devices permitting to synchronise between themselves the vertical translatory movement and the rotary one of the distension of the mobile frames in order to bring them with only one operation from the position of the sofa into the position of a bed and vice versa. Besides, are foreseen tricks, which permit to obtain a stable sofa bed, either in bed position, either in sofa position, or closed, without the use of any locking device. That said, we can note that the sofa beds usually sold which use the above described techniques show some disadvantages, like: a) Impossibility to obtain a bed with a sufficient length in order to permit to a person which is higher than the medium to have a comfortable rest, without increasing for that the encumbrance of the sofa. b) Impossibility for the fixed frame to confer to the sofa an aesthetically pleasant line and in order to hide the double function. The dimension of a normal sofa, whatever its design is, usually foresee a 90 cm depth, of which 55 cm are for the sitting and 35 cm for the back, which height is nearly 45 cm. c) Necessity to rotate the back of the sofa before doing the operation permitting the transformation of the sofa into a bed, i.e. the necessity of a double operation. d) Location of the stuffing of the back, when the sofa bed is in bed position, nearly in direct contact with the ground and though in non-optimal hygienical conditions. e) Necessity to increase the depth of the fixed frame for the support in order to permit the inclination of the first auxiliary mobile frame, i.e. that frame directly connected to the synchronisation lever connected to the other extremity, at the extremity of the member of the pantograph which runs in the horizontal eyelet integral with the mobile frame. f) Danger of crushing the fingers between the synchronisation lever and the mobile frame, either during the formation of the bed, either during the formation of the sofa : such a danger has to be taken in considered because it can happen during any operation of the sofa bed. Main end of the invention is to eliminate all said disadvantages of the sofa bed having an articulated and folding structure. For this end, this invention solves the problem of getting a bed suitable also to people higher than the medium, without increasing the encumbrance of the fixed frame for the support and in order to hide, with a pleasant look, the double function sofa / bed. In the same time, the invention solves the problem of furnishing a mechanism able to synchronise contemporarily, and with adding any operation, the movements that the framework has to do to become a bed. The invention is described here below in a preferred embodiment and is illustrated with the figures of the 5 sheets here enclosed, which show respectively: fig. 1, a side view of the articulated frame in a sofa function; fig. 2, a side view of the frame during the first phase of the transformation into bed; fig. 3, a side view of the frame in an intermediary position of opening; fig. 4, a side view of the frame in a successive phase transformation; fig. 5, a view of the frame when changed in a bed; fig. 6, the blocking device of the auxiliary mobile frame in the releasing phase; fig. 7, a detail of the blocking device in the hooking position. As we can note in the figures, the sofa bed is made of a fixed frame 1 with rectangular plan, in which is inserted all the framework constituting the bed, there including the mattress and a known type of pantographic structure, already used in the construction of the sofa beds, which supports a mobile frame 2. To the mobile frame 2 is hinged a first auxiliary mobile frame 3 having a U-shaped section, to which is hinged a second auxiliary mobile frame 4 connected in turn to a third auxiliary mobile frame 5, which, when they are laying, are forming the horizontal framework supporting the bed mattress. The third auxiliary mobile frame 5 is integral with legs 6 and orthogonal to them, which support the extremity of the bed not supported by the pantographic structure 18. The pantographic structure, lifting it, causes the coming out of mobile frame 2 when, to form the bed, the first auxiliary mobile frame 3 is made rotate. This is due to the fact that the extremities of each of the two bars 7 and 8 which form the double pantograph supporting the mobile frame run each one in an eyelet integral respectively 9 to the fixed frame and 10 to the mobile frame 2 by special little wheels 1 1, when by levers 12 and 13 reciprocally hinged with pin 14 and rotating around a pin 25 applied on of the horizontal bar of the first mobile frame 2, are subject to a traction from a lever 16 hinged in turn with pin 17 to the first auxiliary mobile frame 3 and the rod 22. The rotation of the first auxiliary mobile frame 3 is caused by the second auxiliary mobile frame 4 hinged in 19 to the first mobile frame 3; the rotation of frame 4 is caused in turn by the third mobile frame 5, by the compound lever 24 and 22 hinged with pin 17 at the first auxiliary frame 3 and at lever 16 which transmits its movement to little wheel 11 running in eyelet 10. Rods 24, 22, 16, 13 and 12 constitute the compound lever which synchronise the movements of the frames constituting the bed. The interconnection rod 20 transmits the movement of the auxiliary frame 4 to the first mobile frame 2 and vice-versa; the little arm of lever 20 keeps in fact the second mobile frame 4 from rotating around the extremity 19 of the first mobile frame without transmitting movement to the first mobile frame 2. The extremity of lever 24 is welded to the third auxiliary mobile frame 5; the supporting leg 6 orthogonally welded to mobile frame 5 itself. During the formation of the bed, the first auxiliary mobile frame 3 acts as an interconnection element between the second auxiliary 4 and the principal mobile frame 2. The second auxiliary mobile frame 4 is blocked to the fixed support frame 1 by the blocking device illustrated in details in fig. 6 and 7. Said device is constituted by a hook 33 hinged in point 40 and reactioned by a spring 35. The hook is driven by the little lever 36 connected to a flexible tie-rod 37, provided at its extremity with a pommel 38. The tie-rod 37 runs through the hole of a L shaped plate 42 which blocked it when the hook is in closing position. The lever 22 which causes the blocking of the second auxiliary mobile frame 4 is provided with a pin 32 which goes to thread itself into the fork 34 when the second mobile frame 4 is folded to form the sofa: by the hook 33, the pin 32 remains blocked into the fork 34.

Claims: CLAIMS 1 ) "Improvements to an articulated folding structure for sofa bed", the articulated structure including: - a fixed frame for the support ( 1 ); - a main mobile frame (2) connected to the fixed frame by a pantographic structure ( 18) reactioned by springs (27) which lift it in a vertical direction, from the bottom to an operative position upwards the fixed frame itself; - a first auxiliary mobile frame (3) connected to the main mobile frame (2) in correspondence with an axis of hinging (15); - a second auxiliary mobile frame (4) connected to said first auxiliary mobile frame (3) in correspondence with a second axis of hinging (19); - an interconnection lever (20) between the main mobile frame (2) and the second auxiliary mobile frame (4) permitting the rotation of the auxiliary mobile frames (3) and (4) in order to line them consecutively between themselves and to the main mobile frame (2), characterised in that they include a third auxiliary frame (5) integral with two supporting legs (6) orthogonal to it, hinged to the second auxiliary frame (4) in correspondence with an axis of hinging (21) and a mechanism which synchronise the contemporaneous movement of vertical lifting and lowering of the main mobile frame (2) with the rotations made by said auxiliary mobile frames (3), (4) and (5). 2) Improvements as claimed in claim 1, characterised in that the auxiliary mobile frame (5) acts as a support for the stuffing of the back of the sofa and in the same time causes the lengthening of the longitudinal structure of the bed; 3) Improvements as claimed in claim 1, characterised in that the mechanism which synchronises contemporaneously the movement of lifting and lowering of the main mobile frame and auxiliary mobile frames includes a first lever (12) hinged on the extremity of one of the two bars of the pantographic structure to make it run by a little wheel (11) in an eyelet (10) integral with the fixed frame (1) and parallel to the axis of the main mobile frame (2), a second lever (13) hinged in correspondence with an axis of intermediate hinging (25) to the main mobile frame (2) and the first extremity, at the first lever (12) in correspondence with an axis of hinging (14) and, at the second extremity, in correspondence with an axis of hinging (26), with a third lever (16) hinged contemporaneously in correspondence with an axis of main hinging (17) to the first auxiliary frame (3) and to a lever (22) connected to the other extremity, to a lever (24) integral with a third auxiliary mobile frame (5) by a pin (23), the shiftings of the lever (12) to cause the running of the extremity of the bar (8) of the pantograph in the groove (10) being caused by the lever (13) and the lever (16) from the rotation of the first mobile frame (3) in turn caused by the second auxiliary frame (4) and by the third auxiliary frame (5) by the lever (22) which synchronises the movement of said third frame (5) itself. 4) Improvements as claimed in claim 3, characterised in that the opposed extremity of the other bar (7) which constitutes the pantographic structure (18) runs by a little wheel (11) in an eyelet (9) integral with the fixed frame for the support (1). 5) Improvements as claimed in claims 3 and 4, characterised in that the eyelets in which run the extremities of the bars (7) and (8)of the pantograph are adjacent to the first auxiliary frame (3) and in that the lever (12) which causes the opening of the pantographic structure (18) in order to lift the main mobile frame (2) is subject to an axial compression from the mechanism constituted by the lever (13) and the lever (16) hinged to the first auxiliary mobile frame (3) 6) Improvements as claimed in claims 3 and 4, characterised in that the lining up of the axis of the frame (5) with the axis of the frame (4) and the frame (3) is realised by the lever (22) when the frame (3) rotates to be lined up with the main mobile frame (2). 7) Improvements as claimed in claim 1, characterised in that the mattress is supported contemporaneously by the main frame (2) and by the auxiliary frames (3), (4) and (5), i.e. is folded in three parts respectively along the first main mobile frame (2), the mobile frame (4) and the mobile frame (5). 8) Improvements as claimed in the former claims, characterised in that the blocking of the folding framework to define the sofa position is carried out by means of a blocking device formed by a hook (33) hinged in point (40) and reactioned by a spring (35) driven by a little lever (36) connected to a flexible tie-rod (37), provided at its extremity with a pommel (38), the flexible tie-rod (37) sliding through the hole of a L shaped plate (42) which blocked it when the hook is in a closing position, the lever (22) of the articulated structure which causes the blocking of the second auxiliary mobile frame (4) being provided with a pin (32) which goes to thread itself into the fork (34) remaining blocked when said second mobile frame (4) is folded to form the sofa.

Inventors: LOIUDICE GIUSEPPE, LOIUDICE, GIUSEPPE
Applicants: LOIUDICE GIUSEPPE, LOIUDICE, GIUSEPPE
Application year: 1998
Main classification: A47C17
IPC codes: A47C17