This invention relates to damped hinge assemblies, in particular though not exclusively, for use in furniture.

In many technical fields, the need is known to damp movements of movable parts such as doors, sliding doors and drawers which are commonly present in a large number of items in daily use, such as, for example, furniture components, household appliances, computers or telecommunications devices. This need is particularly relevant in applications where the movement takes place partially or completely under the action of resilient forces. In fact, in these cases, it is virtually inevitable that the action of these forces will generate an impact at the end of the travel of the movable part against its limit stop. These impacts are potentially damaging for the components of the furniture or the devices which comprise the moving parts. In order to reduce or eliminate these negative effects, damping devices are commonly used which can make the travel of the moving parts more fluid and continuous. A particularly significant case consists of hinges, and in particular hinges for furniture: in the most common version these consist of two main elements, i.e. the mounting arm and cup flange, which are secured respectively to the fixed part (frame) and to the door of the furniture, and are connected to one another by means of link elements, such as to form an articulated quadrilateral linkage. Normally, within the hinge, there is inserted a spring mechanism which, starting from an appropriate opening angle, returns the cup flange, and therefore the door, towards the closed position. If the door is left free to move within the angle of action of the hinge closure mechanism, the spring is released, thus continuing to increase the kinetic energy of the door as far as the closure limit stop on the frame of the furniture; at this point the kinetic energy accumulated by the door is discharged instantaneously with an impact which the conventional rubber stops or buffers can attenuate only slightly. The undesirable effect of the impact can be eliminated completely only by resorting to damping systems which act on a significant arc of the working stroke of the spring closure mechanism. In order to achieve this aim, it is particularly advantageous to use a damping system which works directly on the articulations of the hinge. The best result is obtained with a damping mechanism which is completely contained within the structure of the hinge itself. By this means two other advantages are obtained: there is no additional element which would detract from the appearance of the hinge, and furthermore, using the same structure as for a standard hinge, it is possible to use components which already exist, and the new product line can be used as an alternative to hinges of the conventional type, without disrupting the user's production system. It has in fact been this option which designers have chosen prevalently in recent years: most of the solutions proposed, apart from technical variants which concern mainly the method of application of the damper, always include the use of a fluid damper of the conventional type inserted inside the foot of the hinge. This solution has the advantage of using in the best way the narrow space available in a quadrilateral hinge of the conventional type. In fact, the mounting arm of the hinge has a form which is typically elongate in the direction perpendicular to the plane of the door limit stop, and is therefore particularly suitable for accommodating in its interior, without significant alterations of its form, a standard fluid damper which nevertheless has a distinctly elongate form in the direction of the force which is to be damped. Examples of applications of this type are described in patents EP 1375797Al (Fu-Luong), WO2008077520A1 (Mepla) and WO2008025595A1 (Hettich).

However, this type of solution has only an aesthetic advantage, and in fact if the interior of the mounting arm is occupied by the damper, it is not possible to use the same systems for securing to the frame of the furniture as those which are used for hinges without a damper. In fact the latter have clip mechanisms, screws, or adjustment systems which are normally located in, or pass through, the central part of the foot.

The general purpose of the present invention is to eliminate the aforementioned disadvantages, by using a damping device which occupies the minimum space in the interior of the mounting arm, and leaves space to accommodate securing and adjustment mechanisms of a standard type. For this purpose, it is proposed to use a new-generation fluid damper provided with a rotary shaft of the type described in Italian patent applications no. LC2008A000011 and LC2008A000012. The particular feature of these dampers is that they convert the rotational motion of an exterior element into linear movement of a piston or pistons immersed in fluid in a chamber inside the damper. Since they do not use a piston rod of a conventional type, the dampers which are based on this principle are far more compact, and have a ratio between the extent of the force to be damped and the total length of the damper which is decidedly more favourable.

By way of example, various embodiments of the present invention will now be described with reference to the accompanying drawings, in which:

Figure 1 represents a perspective view from above of a hinge assembly according to the invention,

Figure 2 represents a perspective view from beneath of the hinge assembly of Figure 1 ,

Figure 3 represents a cross-sectioned side view through the mid plane of the hinge assembly of Figure 1, Figure 4 represents an exploded perspective view of the parts of the hinge assembly of Figure 1 , Figures 5 and 6 illustrate from underneath a second form of hinge assembly according to the invention, shown respectively in partially open and closed positions,

Figures 7 and 8 show in detail the driving gear and inner link of the hinge assembly of Figures 5 and 6,

Figures 9a to 9d illustrate the manner of operation of the hinge assembly of Figures 5 and 6 in a typical installation,

Figure 10 illustrates a third form of hinge assembly according to the invention, and Figure 11 shows a modified form of damper.

As seen in the drawings, a hinge assembly 10 comprises a part which is known as the mounting arm 11, to be secured to the frame, and a movable part 12, known as the cup flange, to be secured to the door of a cupboard. The mounting arm 11 is advantageously made of metal plate which is bent so as to form a channel in the shape of a "C". The two parts 11 and 12 are connected to one another by a known technique, by means of an articulated quadrilateral linkage constituted by outer 13 and inner 14 links and by four connection pins 15, 16, 17 and 18. In the representation shown in the drawings, the inner link 14 in turn, according to the known art, consists of a set of parallel plates which are joined together to form a single component of the linkage. Around the pin 16 is wound a double torsion spring 19, which has a pair of end arms 20 supported on the inner surface of the upper part of the mounting arm 11. The central portion 21 of the spring 19 is supported on a protuberance 22 of the inner link 14, thus generating a force on the inner link which, when the hinge is near to being closed, is translated into a moment which urges the cup flange 12, and thus the door, towards its closed position. On a plane perpendicular to its pivotal axis, one of the end edges of the inner link 14 has toothed gear means 23 which can transmit the rotational movement of the link itself. On the lateral surface opposite the toothed gear means 23 of the link 14, the mounting arm 1 1 has two profiles 24 and 24' which form two parallel guide reliefs inside the lateral surface of the mounting arm itself. Inside the mounting arm 11 is secured the damper 25 with a rotary shaft 27 (shown in Figures 1, 2 and 3 with its housing 26 partially in cross-section) held rigidly in position by means of the inner reliefs of the profiles 24 and 24', such that the axis of its rotary shaft 27 is parallel to the axis of articulation of the hinge. On the outer end part of the rotary shaft 27, there is secured so as to be integral in rotation an element 28, which in turn bears on its outer surface toothed gear means 29 which can be connected to the toothed gear means 23 of the inner link 14. The damper 25 is dimensioned so as to be positioned inside the mounting arm, such that the rotation of the inner link 14 is transmitted by the toothed gear means 23 and 29 directly to the shaft 27. By this means, when the hinge assembly 10 closes with anti-clockwise movement of the cup flange 12 (indicated by the arrow in Figure 3), the inner link 14 rotates around the pin 15 in a clockwise direction, thus drawing in opposite rotational motion the element 28, and together with this the shaft 27. According to the manner of operation of the rotary shaft damper 25, the rotation of the shaft 27 causes the displacement of the piston 30 inside the housing 26. Because of the play which is present in the piston / housing and piston / shaft connections, movement of the non-compressible fluid which fills the container across the piston gives rise to the desired damping effect on the thrust exerted by the spring 20.

The advantage which is provided by the use of a rotary shaft damper in order to brake the closing of a hinge is obvious: for the same useful extent of travel of the piston, the axial dimension of the damper is decidedly smaller than a fluid damper of a conventional type; in addition, the direct conversion of the rotational movement of the external element to the working stroke of the piston is particularly advantageous in the case of the hinge assembly, in the interior of which, because of the nature of the object itself, it is always possible to place rotational components. As a result of these factors, as specified in the above-described applications, it is possible to position the rotary shaft damper in the interior of the mounting arm, such that the axis of movement of the piston is parallel and not perpendicular to the axis of articulation of the hinge, thus providing a considerable advantage in terms of reduction of space. As can be seen in Figures 2 and 3 in particular, most of the space inside the mounting arm 1 1 is free, which makes it possible to use securing elements of a conventional type. For example on the back of the mounting arm 11 there are present the "T"-tyρe screw 31, the through oval cavity 32 and the central cavity 33, which a person skilled in the art can easily recognise as elements for securing and access to the adjustment units for a preassembly base for furniture of a standard type.

The form of hinge assembly seen in Figures 5 to 9 is similar to the assembly of Figure 1 in that a rotary shaft damper 225 is incorporated into a toggle type hinge 210 to provide damped resistance to its pivotal movement. The damper 225 is again arranged to be mounted within the mounting arm 211 of the hinge 210, i.e. the part of the hinge that is normally anchored to the cupboard frame or carcase, and is arranged to be actuated upon pivotal movement of the hinge cup 212, i.e. the other part of the hinge that is normally attached to the cupboard door.

The mechanism for actuating the damper 225 again comprises a toothed driving gear 223 that is arranged to mesh with the toothed pinion 229 mounted on the drive shaft 227 of the damper, where the driving gear is itself driven by pivotal movement of the hinge. As before, the driving gear 223 is designed to be mounted on one of the pins 215 by which an inner link 214 of the hinge 210 is mounted. In this case, however, the driving gear 223 is not connected directly to the inner link 214 so as to pivot therewith. Instead, the connection between the driving gear 223 and the inner link 214 incorporates a lost motion mechanism. As will be seen more clearly from Figures 7 and 8, rotational drive from the inner link 214 is designed to be transmitted to the driving gear 233 via a pawl 251. The driving gear 223 is mounted on the pin 215 of the inner link 214 so as to be freely rotatable thereon, with the pawl 251 engaging in an arcuate slot 250 in the driving gear 223. The pawl 251 drives the driving gear 223 when it abuts against one end or other of the arcuate slot 250. Because the pawl 251 is shorter than the arcuate slot 250, however, this means that drive will not be transmitted to the driving gear 223 when the pawl 251 is in an intermediate position between the ends of the slot. This is the lost motion mechanism and the way that it operates in practice is illustrated in Figures 9a to 9d.

In Figure 9a, the cupboard door D is seen in its fully open position. The driving gear 223 is seen in meshing engagement with the toothed pinion 229 of the damper, with the pawl 251 of the inner link 214 located at a first end of the arcuate slot 250. As the door starts to close, in the direction of arrow A in Figure 9b, the inner link 214 starts to pivot about its pin 215 (clockwise in Figure 9b). Because of the starting position of the pawl 251, however, this initial movement of the door will not cause the pawl to drive the driving gear 223: the pawl will simply move towards the other (second) end of the arcuate slot 250, whilst the driving gear remains stationary. Only when the pawl 251 has reached the second end of the arcuate slot 250 and is in abutment with it will the pawl be able to deliver rotational drive to the driving gear 223. The driving gear 223 will be driven by the pawl 251 in this manner as the door continues to close, until it reaches its fully closed position, which is seen in Figure 9c. As the driving gear 223 is driven to rotate, so in turn will it drive the toothed pinion 229 of the damper to rotate, thus causing the damper to respond with a damped resistive force. This force is transmitted back through the assembly to the door, thereby damping its final closing movement.

Figure 9d shows what happens when the door is opened again and in that case, the lost motion device works essentially in reverse. Opening of the door, in the direction of arrow B in Figure 9d, will cause the inner link

214 with its pawl 251 to pivot, this time in the opposite direction to before

(anti-clockwise in Figure 9d). Because of the starting position of the pawl

251 within the arcuate slot 250 now, however, movement of the pawl will not drive the driving gear 223. Drive will only start to be delivered by the pawl

251 to the driving gear 223 once the pawl has re-engaged the opposite (first) end of the arcuate slot 250. When that happens, continued opening of the door will cause the pawl 251 to drive the driving gear 223 back towards its original starting position. This rotation of the driving gear 223 causes a corresponding rotation of the toothed pinion 229 of the damper. If the damper is one that operates in either direction, this rotation of the toothed pinion 229 means that the damper will again respond with a damped resistive force, thereby transmitting damping to the door in the final stage of its opening movement. It is to be noted that even though rotational drive is not always being transmitted between the driving gear and the toothed pinion, the two nevertheless remain in constant meshing engagement. This creates less risk of a jam, that could occur if the gears were alternatively designed to move periodically into and out of engagement with one another.

It will be appreciated that the lost motion mechanism could be incorporated into other parts of the assembly and in other ways. For example, the pawl and arcuate slot arrangement described above could form part of the geared drive element of the damper, in which case the inner link could have a plain toothed pinion connected directly to it or possibly even formed as an integral part of it.

The assemblies described above could be designed to deliver a damped resistive force in response only to the closing movement of the door. In that case, the damper in the assembly described above could be designed to incorporate a valve mechanism in its piston so that it only works in one direction. Alternatively, it might be preferred for the assembly to deliver a damped resistive force to the door on both its opening and closing movements. In that case, the damper would work in both directions and so not need a valve mechanism. In the example described above, damping would typically be designed to be delivered by the assembly over the final 20°-30° of the closing movement of the door and again over the final 20°-30° of its opening movement.

The point at which the damper is actuated by the movement of the door is determined by the lost motion mechanism of the pawl and arcuate slot arrangement and thus the assembly can be tailored to suit different applications. In a useful modification, the lost motion mechanism could be designed to be adjustable. In the assembly of Figure 5, for example, the driving pinion could be designed as a compound part with a slidable piece to allow shortening of the arcuate slot. If the slot is made effectively shorter, this will reduce the amount of "lost motion" in the system and mean that the damper will be actuated earlier in the movement of the door.

Another form of lost motion mechanism is seen in Figure 10. Here, the driving gear 323 is formed as an integral part of the inner link 314 of the hinge. The driving gear 323 is arranged to mesh with the toothed pinion 329 of the damper. In this case, however, the drive shaft 327 of the damper is formed with a winged configuration, whilst the toothed pinion 329 has a bore that is formed with segmented cutaways 350. As will be understood from Figure 10, the arrangement means that rotation of the toothed pinion 329 will actuate the damper only when the winged shaft 327 abuts one side or other of the segmented cutaways 350. The winged shaft 327 has freedom to rotate within the segmented cutaways 350 between these two angular end positions and it is this that provides the "lost motion" in this example. As with the assemblies described above, it is to be noted that the driving gear is designed to remain in constant meshing engagement with the toothed pinion. It will of course be understood that this design could equally well be incorporated into the driving gear on the inner link instead.

The design of the damper seen in Figure 5 could be modified as shown in Figure 11. Instead of being held by its housing and driven by the toothed pinion on its rotary shaft, here the damper 425 is held by its shaft 427, whilst its housing 426 is driven to rotate. For this purpose, the housing 426 comprises gear teeth 429 that are designed to work with the teeth of the driving gear (not shown). An advantage of this arrangement is that the meshing teeth of both elements can be made much longer (in the axial direction), which greatly helps in spreading the transmission forces over a greater area. The arrangement also facilitates the design of the drive shaft 427 of the damper 425.

In the assemblies described above, rotational drive for the damper is arranged to come from the inner link of the hinge. It will be understood, however, that the drive could instead be arranged to come from other parts of the hinge, for example the outer link, or even possibly from the door itself.