ITMI20110297A1 - LIFTING SYSTEM FOR DOORS OF A MOBILE OSCILLANTS AROUND A HORIZONTAL AXIS - Google Patents

Description

Description of a patent application for an industrial invention

DESCRIPTION

The invention concerns a lifting system for furniture doors, oscillating according to a horizontal axis, in particular for lifting hood doors.

In the furniture sector, the use of lifting systems to support and move vertically the doors of hoods is known, each of which systems comprises one or more support levers articulatedly connected between the body of the furniture and the door to be lifted. , as well as comprises an elastic device, for example a gas spring, operatively connected to the lever to exert the force necessary for lifting the door.

Conventionally, the operative connection between the lever and the elastic device can be made indirectly through an intermediate oscillating member, to which the elastic device is connected, which member has a roller which acts on a cam of the support lever to transmit the force of the elastic device to the lever itself.

Alternatively, the operative connection between the lever and the elastic device can be made directly by providing a pivot pin on the support lever to connect the piston rod of the elastic device itself, the pin being arranged at a distance from the axis of oscillation of the support lever, this solution which is preferable due to the greater constructive simplicity.

As part of these lifting systems, there is a need to be able to control the lifting movement during its unwinding, in particular in the area where the moment generated by the weight of the door reaches its peak, as well as the need to be able to keep the door still in any position during Γ opening, once the desired position has been reached. In fact, since the gas spring provides a force that varies in a limited way during its extension, in such lifting systems, especially if the gas spring is directly connected to the lever, it may happen that the torque exerted by the spring during a first arc opening of the hood is preponderant with respect to the torque opposed by the weight force of the door or doors, while in another opening arc, corresponding to the maximum extension of the hood towards the outside of the cabinet, in which the torque due to the weight of the door assumes the greater the value, the torque of the spring is lower than it, not allowing to support the hood in the desired position nor to push it towards the maximum open position.

In addition, for the purpose of effectively lifting the door, there is a need to achieve a lifting force that can be adapted to the characteristics of the door, such as the weight, material or thickness of the door.

Finally, from the use of these systems it was possible to detect the technical problem consisting in the fact that the gas spring tends to lose efficiency over time, to the point that it may be unsuitable for providing the force necessary to lift the door or to maintain it. of the leaf in the raised position, with the risk that the leaf itself could fall back.

The main purpose of the invention is therefore to provide a lifting system capable of meeting the needs of the user and solving the problems mentioned above.

As part of this technical task, an object of the invention is to provide a lifting system for doors of a piece of furniture oscillating around a horizontal axis that provides precise control of the lifting of the door and allows to keep the door unaltered over time. effectiveness of this control.

The technical task, as well as these and other purposes, according to the present invention are achieved by realizing a lifting system for a furniture door swinging around a horizontal axis having a first elastic device operatively connected to a door support lever to provide a moment in the closing direction of the leaf in correspondence with the closed position of the leaf, and a primary moment in the opening direction of the leaf starting from a position of partial opening of the leaf, characterized in that it comprises a second operationally connected elastic device to the support lever to provide a force capable of generating an auxiliary moment in the direction of opening of the leaf and / or a moment of contrast by friction against the support lever, said auxiliary moment and / or said moment of contrast operating in the direction of opening of the door, respectively in the opposite direction to the movement of the door, along an arc of its oscillation starting from a partially open position.

While the auxiliary opening moment is added to the opening moment generated by the first elastic device, the frictional moment is able to oppose the movement of the hood, compensating for any differences between the moments generated by the first elastic device and the weight force, so as to keep the hood in balance. Preferably the swing arc of the door in which said second elastic device intervenes is within the position of maximum extension of the door towards the outside of the cabinet.

The second elastic device is configured in such a way as to provide, in correspondence with said swing arc of the door, an auxiliary moment in the direction of opening of the door which, added to the primary moment in the direction of opening of the door, substantially equals or it prevails over the moment in the closing direction of the door due to the weight force of the door and the other parts integral with it. Preferably, the second elastic device has means for adjusting its own force generating said auxiliary moment and / or said contrast moment.

By means of these adjustment means it is possible to intervene on the device so as to modify its operation, depending on whether a movement of the leaf is desired that remains in equilibrium in the various partial opening positions or whether continuous opening operation of the leaf is preferred with more or less fast movement.

Furthermore, these adjustment means are particularly advantageous for adapting the operation of the device to different weights of doors of different material or thickness.

Preferably, the second elastic device has a friction surface sliding along a cam provided on said support lever.

Preferably the second elastic device comprises a leaf spring having said friction surface.

Preferably, said leaf spring has an angular configuration defining a first spring arm on which said friction surface and a second spring arm are present.

Preferably, said adjustment means comprise an element for adjusting the prestressing of said leaf spring.

Preferably, said adjusting element comprises an eccentric operatively engaged with said second arm of said leaf spring.

In a further embodiment, the second elastic device comprises, alternatively or in combination with said adjustment element, elements which rest on regions of said cam with differentiated friction, made in particular of different material. Further characteristics and advantages of the invention will become more evident from the description of a preferred but not exclusive embodiment of the lifting system for doors of a piece of furniture swinging around a horizontal axis according to the invention, illustrated by way of non-limiting example in the attached drawings. , in which:

Figure 1 shows a side elevation view of a double door hood presenting a double door lifting system according to the invention, in the closed position of the double door; figure 2 shows a side elevation view of the hood of figure 1 in a partially open position of the double door;

Figure 3 shows a side elevation view of the hood of Figure 1 in the fully open position of the double door;

Figure 4 shows an enlarged detail of the hood of Figure 1 in the closed position of the double door, with the center in a first position for adjusting the compression of the leaf spring;

figure 5 shows an enlarged detail of the hood of figure 3 in the open position of the double door, with the center in the first position for adjusting the compression of the leaf spring;

figure 6 shows an enlarged detail of the hood of figure 3 in the open position of the double door, with the center in a second adjustment position which corresponds to a greater compression of the leaf spring with respect to the first adjustment position;

Figure 7 shows a side elevation view of a single door hood presenting a door lifting system according to the invention, in the closed position of the door;

figure 8 shows a side elevation view of the hood of figure 7 in the open position of the door;

Figure 9 graphically shows the trend of the moments to which the double door is subjected as a function of the opening angle of the upper door, also varying the adjustment through Γ eccentric;

Figure 10 graphically shows the trend of the moments to which the double door is subjected as a function of the opening angle of the upper door, also varying the performance of the gas spring.

Equivalent parts of the lifting system of the two illustrated hood versions will be indicated with the same numerical reference.

With reference to the aforementioned figures, a lifting system is shown for furniture doors, such as hoods, which have an axis of oscillation around a horizontal axis.

With reference to the embodiment illustrated in Figures 1 - 6, the hood 2 has an upper door 3 constrained by one or more hinges 4 of a known type to the internal side of the cap 5 of the hood 2, and by means of one or more hinges 6 of a known type to a lower leaf 7 in turn constrained to at least one support lever 9 by means of a decelerated hinge 8 of a known type positioned inside the lower leaf 7.

The support lever 9, at the opposite end to that articulated with the hinge 8, is constrained by means of an oscillation pin 10 to a plate 11 applied to the internal side of a shoulder 12 of the hood 2.

The axes of oscillation defined by the oscillation pin 10 and by the hinges 4, 6, 8 are all oriented parallel and horizontally in the direction of the width of the hood 2.

With reference to the embodiment illustrated in Figures 7 and 8, the hood 23 has a single door 13 constrained by one or more decelerated hinges 14 of a known type to the internal side of the cap 15 of the hood 23 and, by at least one kinematic chain comprising a connecting rod 17 and a support lever 19, to a plate 21 applied to the internal side of a shoulder 22 of the hood 23.

The detail of the door 13 is constrained, by means of at least a hinge 16 of a known type, to one end of the connecting rod 17, the opposite end of which is in turn constrained, by means of an oscillation pin 18, to the support lever 19 in turn constrained, by means of an oscillation pin 20, to the plate 21.

The axes of oscillation provided by the pivot pins 18 and 20 and by the hinges 14 and 16 are all oriented parallel and horizontally in the direction of the width of the hood 23.

The hood 2 and respectively the hood 23 have a respective system for moving the doors 3 and 7 and respectively of the door 13 comprising a first elastic device operatively connected to the support lever 9 and respectively to the support lever 19 to provide a moment in the direction closing of the leaves 3 and 7 and respectively of the leaf 13 in correspondence with the closed position of the leaves 3 and 7 and respectively of the leaf 13, and a primary moment in the opening direction of the leaves 3 and 7 and respectively of the leaf 13 a starting from a position of partial opening of leaves 3 and 7 and respectively of leaf 13.

The elastic device of the hood 2 and respectively of the hood 23 comprises a gas spring 24 having the cylinder 25 pivoted with an oscillation pin 26 to the plate 11 and respectively to the plate 21, and a piston rod 27 pivoted with an oscillation pin 28 to the support 9 and respectively to the support lever 19.

The pivot pins 26 and 28 of the elastic device of the hood 2 and respectively of the hood 23 are parallel to the pin 10 and respectively to the pin 20.

The system for moving the wings 3 and 7 and respectively of the wing 13 further comprising a second elastic device operatively connected to the support lever 9 and respectively to the support lever 19 to provide an auxiliary moment of an elastic force and / or of a force of friction acting against the support lever 9 and respectively against the support lever 19 in the opening direction of the wings 3 and 7 and respectively of the wing 13, starting from their position of partial opening, along their oscillation arc.

Advantageously, the arc of oscillation of the doors 3 and 7 and respectively of the door 13 in which the second elastic device intervenes is near the position of their maximum extension towards the outside of the piece of furniture, where the closing moment exerted by the weight force of the leaves 3 and 7 and respectively of the leaf 13 and of the other parts integral with them assumes the maximum value.

The second elastic device can be configured in such a way as to deliver, in correspondence with said oscillation arc of the leaves 3 and 7 and respectively of the leaf 13, an auxiliary moment in the opening direction which, added to the primary moment in the opening direction and taking into account the frictions involved, it prevails over the moment in the closing direction of the doors 3 and 7 and respectively of the door 13 due to the weight force of the doors and of the other parts attached to them.

In this case the second elastic device ensures a continuous opening movement of the leaves 3 and 7 and respectively of the leaf 13. But the second elastic device can also alternatively be configured in such a way as to deliver, in correspondence with said oscillation arc of the doors 3 and 7 and respectively of the door 13, an auxiliary moment in the opening direction which, added to the primary moment in the opening direction and taking due account of the frictions involved, substantially balances the moment in the closing direction of the wings 3 and 7 and respectively of the door 13 due to the weight force of the and of the other parts integral with them.

In this case, the second elastic device ensures a plurality of stable partial opening positions of the doors 3 and 7 and respectively of the door 13 in which, if the user releases the grip, the doors remain stationary in the position achieved.

The second elastic device in particular is provided with suitable adjustment means through which, as we shall see, the value of the auxiliary moment delivered can be modulated.

The second elastic device in the illustrated embodiments comprises a leaf spring 29 having a friction surface 30 sliding along a cam 31 provided on the support lever 9 and respectively on the support lever 19. The cam 31 is defined by a suitable surface shaping of the end of the support lever 9 and respectively of the support lever 19, possibly covered with different material, which has the oscillation pin 10 and respectively the oscillation pin 20.

The cam 31 has a neutral portion describing an arc of circumference centered on the oscillation pin 10 and respectively on the oscillation pin 20, along which the elastic force transmitted by the leaf spring 29 is directed radially with respect to the oscillation pin 10 and respectively to the pin of oscillation 20 of the support lever 9 and respectively of the support lever 19, and an active section having a different radius of curvature, along which the elastic force transmitted by the leaf spring 29 has a force arm with respect to the oscillation pin 10 and respectively to the pivot pin 20 of the support lever 9 and respectively of the support lever 19.

The leaf spring 29 has an angular configuration defining a first spring arm 32 on which the friction surface 30 and a second spring arm 33 are present.

The leaf spring 29 has an arched central portion 34 from which the first spring arm 32 extends and on the opposite side the second spring arm 33, both of which have a rectilinear extension. The central arcuate portion 34 is clamped between a block 35 fixed to the plate II and respectively to the plate 21, arranged on the concave side of the arcuate central portion 34, and an orthogonal fin 36 of the plate II and respectively of the plate 21, arranged on the convex side of the central arched section 34.

The means for adjusting the auxiliary moment delivered by the second elastic device can take different forms.

The adjustment means may in fact comprise an element for adjusting the prestressing to which the leaf spring 29 is subjected in correspondence with the closed position of the doors 3 and 7 and respectively of the door 13.

The adjustment element includes in particular an eccentric 37 operatively engaged against the second spring arm 33.

The eccentric 37 is pivoted to the plate II and respectively to the plate 21 by means of an oscillation pin 38 parallel to the oscillation pin 10 and respectively to the oscillation pin 20 and is suitable for performing an eccentric oscillation of about 180 °, limited by a special stop 39, between a first adjustment position (fig. 4) corresponding to a lower prestress of the second spring arm 33 and a second adjustment position (fig. 6) corresponding to a greater prestressing of the second spring arm 33.

The adjustment means can comprise, alternatively or in combination with the eccentric 37, areas of the cam 31 with differentiated friction, and in particular areas of the cam 31 made from each other in different material.

We now refer to figure 9 which graphically shows the trend of the moments to which the double door 3, 7 of the hood of figures 1- 6 is subjected as a function of the opening angle of the upper door 3, in which al indicates the opening angle in which the second elastic device intervenes.

The trend of the moment generated by the first elastic device is represented, for opening angles lower than al, by the thin continuous line, while for opening angles higher than al it is represented by the dashed line.

The trend of the moment in the closing direction of the doors 3, 7 due to the weight of the doors 3, 7 and the parts that rise with them (for example the hinges 6 and 8) is represented by the bold line.

The trend of the moment in the opening direction of the doors 3, 7 generated by the combination of the first elastic device with the eccentric 38 in the first adjustment position and of the second elastic device for opening angles greater than al is represented by the thin continuous line.

The trend of the moment in the opening direction of the leaves 3, 7 generated by the combination of the first elastic device with the eccentric 38 in the second adjustment position and of the second elastic device for opening angles greater than al is represented by the dotted line .

The graph shows that at the closing angle (point of origin of the graph) the moment generated by the first elastic device is negative, i.e. it operates in the direction of closing the doors 3, 7.

The moment generated by the first elastic device, once a certain angle a2 has been reached, is canceled (the straight line of action of the piston 27 of the gas spring against the support lever 9 is directed radially to the oscillation pin 10 of the support lever 9) and once the angle a2 is exceeded it becomes positive, i.e. it operates in the direction of the opening of the leaves 3, 7 (the straight line of action of the piston 27 of the gas spring against the support lever 9 passes from one side to the diametrically opposite side of the pivot pin 10 of the support lever 9).

Up to the opening angle a3, the moment in the direction of closure due to the weight force prevails over the moment in the opening direction exerted by the first elastic device, and the opening of the doors 3, 7 must therefore be assisted by the user.

Once the opening angle a3 has been exceeded, the moment in the direction of closure due to the weight force is exceeded by the moment in the opening direction exerted by the first elastic device and the opening proceeds without the need for user intervention. Once the opening angle at has also been exceeded, at the moment in the direction of opening exerted by the first elastic device, a concordant moment exerted by the second elastic device is added.

The second elastic device operates advantageously around the position of maximum extension of the door towards the outside of the cabinet, that is, when the moment in the direction of closure generated by the weight force assumes the maximum value.

If the second elastic device were not present, the moment in the opening direction of the leaves 3, 7 due to the first elastic device alone would be insufficient to overcome the moment in the closing direction due to the weight force. This is illustrated graphically by the fact that for opening angles greater than a4 the representative curve of the former remains below the representative curve of the latter.

The graph illustrates, for opening angles greater than al, an overlap between the curve of the moment in the opening direction generated by the combination of the first elastic device and the second elastic device with eccentric Γ 38 in the first adjustment position, and the curve of the closing moment generated by the weight force.

In correspondence with this overlapping section, the doors 3, 7 have a stable position of partial opening maintained in the absence of user intervention.

If the user adjusts the eccentric 38 to the second adjustment position, which corresponds to a greater prestress of the leaf spring 29 and consequently to a greater elastic force transmitted by this to the cam 31, the moment in the opening direction generated by the combination of the the first elastic device and the second elastic device becomes preponderant with respect to the moment in the closing direction generated by the weight force, and the wings 3, 7 open completely automatically without the need for intervention by the user.

Let us now refer to figure 10 which graphically shows the trend of the moments to which the double door 3, 7 of the hood of figures 1- 6 is subjected as a function of the opening angle of the upper door 3, as the performance of the first one varies. elastic device, it being known in particular that the gas spring can undergo a progressive deterioration in performance over time, in particular due to small gas leaks.

The trend of the moment generated by the first elastic device at full efficiency is represented by the solid line, while the trend of the moment generated by the first elastic device with performance loss is represented by the dotted line. The trend of the moment in the closing direction of the doors 3, 7 due to the weight of the doors 3, 7 and the parts attached to them is represented by the bold line.

The trend of the moment in the opening direction of the leaves 3, 7 generated by the combination of the first elastic device and the second elastic device for opening angles greater than al, which is the first intervention angle of the second elastic device, is represented by dash line point.

The graph shows that without the aid of the second elastic device, in the event of a loss of performance, the first elastic device could not obtain the complete automatic opening of the leaves 3, 7 since, once the opening angle a4 is exceeded, the moment in the direction of the closing due to the weight force would prevail over the moment in the opening direction exerted by the first elastic device.

It should be noted that the calibration of the second elastic device can be made according to preferences in such a way as to cause a continuous movement of the leaves 3, 7 towards the position of complete opening without the intervention of the user (the curve of the moment in the sense opening generated by the combination of the first and second elastic device remains permanently above the curve of the moment in the closing direction generated by the weight force, as shown in the graph in figure 10) or a movement through stable positions of partial opening (the curve of the moment in the opening direction generated by the combination of the first and second elastic device overlaps for a stretch the curve of the moment in the closing direction generated by the weight force, as shown in the graph in figure 9).

In practice it has been found that the lifting system for furniture door according to the invention is suitable for ensuring complete control of the door opening.

The lifting system for furniture door thus conceived is susceptible of numerous modifications and variations, all falling within the scope of the inventive concept; furthermore, all the details can be replaced by technically equivalent elements.

In practice, the materials used, as well as the dimensions, may be any according to the requirements and the state of the art.

Claims (14)

CLAIMS 1. Lifting system for furniture door oscillating around a horizontal axis having a first elastic device (24) operatively connected to a support lever (9, 79) of the door (3, 7, 13) to provide a moment in the closing direction of the leaf (3, 7, 13) in correspondence with the closed position of the leaf (3, 7, 13), and a primary moment in the opening direction of the leaf (3, 7, 13) starting from a partial opening position of the leaf (3, 7, 13), characterized in that it comprises a second elastic device operatively connected to the support lever (9, 19) to provide a force capable of generating an auxiliary moment in the opening direction of the leaf and / or a moment of contrast due to friction against the support lever (9, 19), said auxiliary moment and / or said contrast moment operating in the opening direction of the leaf (3, 7, 13), respectively in the opposite direction to the movement of the leaf, along an arc of its oscillation starting from a position of partial opening. 2. Lifting system for furniture door swinging around a horizontal axis according to the preceding claim, characterized in that said swing arc of the door (3, 7, 13) in which said second elastic device intervenes is around the position of maximum extension of the door (3, 7, 13) towards the outside of the cabinet. 3. Lifting system for furniture door oscillating around a horizontal axis according to any preceding claim, characterized in that said second elastic device is configured in such a way as to provide, in correspondence with said oscillation arc of the door (3, 7, 13), an auxiliary moment in the opening direction of the leaf (3, 7, 13) which, added to the primary moment in the opening direction of the leaf (3, 7, 13), prevails over the moment in the closing direction of the door (3, 7, 13) due to the weight force of the door (3, 7, 13) and of the other parts integral with it. 4. Lifting system for furniture door oscillating around a horizontal axis according to any claim 1 and 2, characterized by the fact that said second elastic device is configured in such a way as to provide, in correspondence with said arc of oscillation of the door (3 , 7, 13), an auxiliary moment in the opening direction of the leaf (3, 7, 13) which, added to the primary moment in the opening direction of the leaf (3, 7, 13) substantially balances the moment in the closing direction of the leaf (3, 7, 13) due to the weight force of the leaf (3, 7, 13) and of the other parts integral with them to achieve a plurality of stable partial opening positions of the leaf (3, 7 , 13). 5. Lifting system for furniture door oscillating around a horizontal axis according to any preceding claim, characterized in that said second elastic device has means for adjusting its own force generating said auxiliary moment and / or said contrast moment. 6. Lifting system for furniture door oscillating around a horizontal axis according to any preceding claim, characterized in that said second elastic device has a friction surface (30) sliding along a cam (31) provided on said support lever (9, 19). 7. Lifting system for furniture door oscillating around a horizontal axis according to the preceding claim, characterized in that said second elastic device comprises a leaf spring (29) having said friction surface (30). 8. Lifting system for furniture door swinging around a horizontal axis according to the preceding claim, characterized in that said leaf spring (29) has an angular configuration defining a first spring arm (32) on which said surface is present of friction (30) and a second spring arm (33). 9. Lifting system for furniture door oscillating around a horizontal axis according to any one of claims from 6 to 8, characterized in that the second elastic device comprises elements which rest on areas of said cam (31) with differentiated friction. 10. Lifting system for furniture door oscillating around a horizontal axis according to the preceding claim, characterized in that said areas of said cam (31) with differentiated friction are made of different material. 11. Lifting system for furniture door oscillating around a horizontal axis according to any claim from 7 to 10, characterized in that said adjustment means comprise an element for adjusting the compression of said leaf spring (29). 12. Lifting system for furniture door swinging around a horizontal axis according to claims 8 and 11, characterized in that said adjustment element comprises an eccentric (37) operatively engaged with said second arm (33) of said leaf spring (29). 13. Lifting system for furniture door oscillating around a horizontal axis according to any preceding claim, characterized in that said first elastic device comprises a gas spring (24). 14. Furniture having a plurality of swinging doors according to a horizontal axis, characterized in that it has a lifting system according to one or more preceding claims.