Background of the Invention There is known from the art a hinge arrangement for the cabinet door of a refrigeration appliance which allows the opening and closing of the door from either side thereof and comprising four hinge seats, generally in the form of slots provided-in plates which are each horizontally affixed close to each of the upper and lower ends of the door or cabinet and close to the right and left end portions thereof. In the interior of each slot is fitted, by the horizontal angular displacement of the door, a vertical hinge pin which is secured to the other of said parts defined by the door and the cabinet, upon the closing of the respective door side. In order to guarantee that the hinge pins of the door side, which is opposite to that selected by the user to be opened, remain retained in the interior of the respective hinge seats, bearing and defining the articulation for the opening and closing rotation of the door, there is provided a lock slider, generally in the form of an elongated bar which is guided in that door or cabinet part which sustains the hinge seats, so as to be linearly displaced in opposite directions, from a closed door median position, towards one or the other side of the door or cabinet.

The opposite ends of the lock slider are provided with respective cam portions which are arranged so that the lock slider is displaced, by the hinge pin at the

opening side of the door, towards the other side, in order to lock the hinge pin of this other side inside the respective hinge seat. Thus, when the door begins to be opened from either side, the lock slider is automatically and immediately forced to move towards the other side, locking the hinge pin of this other side and preventing the door from being detached from the cabinet while it is maintained open.

The lock slider is medianly provided with a V-shaped marginal cut so as to operate jointly with a positioning pin which is mounted to be pressed, by contact with the other door or cabinet part, against the V-shaped cut, when the door reaches a position immediately anterior to the closing thereof. In this situation, the positioning pin begins to press one of the inclined walls of the V-shaped cut, forcing the lock slider to the median position and allowing, with the full closing of the door, the hinge pins to be adequately locked in their respective hinge seats by the cam portions at the opposite ends of the lock slider, preventing the door from being detached from the cabinet.

In the type of construction considered above, the locking of the hinge pins is guaranteed by the lock slider in the open door condition, with no possibility of the door falling down, since its opening from either of its sides is only possible as a function of the dimensioning of the lock slider, with the displacement of the latter to the other side to a condition in which the hinge pin is mandatorily locked to said other side.

However, when the door is in the open condition at one side, with the lock slider displaced to the other side, it is possible for the user to manually press the positioning pin, which is mounted to the door or

cabinet part that carries the lock slider, towards the V-shaped cut of the latter, to cause the displacement of the lock slider to the median position, from which the door can be detached from the side still hinged to the cabinet, so that the hinge pin of this side actuates on the adjacent cam portion of the lock slider, forcing the latter to move towards the already opened side and completely releasing the door from its connection with the cabinet.

While the complete release condition of the door, as mentioned above, is only possible when the user acts deliberately and unduly onto the positioning pin, manually forcing it against the lock slider, in case said condition occurs by negligence or by action of children, the door may fall and cause serious injuries and material losses to the user.

It should be noted that even in the assemblies in which the positioning pin is secured to the part carrying the hinge pins, it is possible for the user to insert any pin in the orifice of the other part which gives access to the V-shaped cut of the lock slider, and to force the latter to the median position, from which it can be displaced by the hinge pin itself when the respective door side is forced to the opening direction.

Brazilian Patent Application PI 0006260-0 (WO 02/46560) of the same applicant discloses a hinge construction such as described above, which incorporates a safety device to prevent the door from being detached from the cabinet by displacement of the lock slider to the median position, after the door has been opened by one of its sides.

The safety device proposed in said prior document comprises, at each hinge point of the door, stop means which are respectively affixed to the door and to the

cabinet and which cooperate with each other at the hinge side of the door, from a certain opening degree of the latter from the other side, in order to prevent the hinge pin under operation from being removed from its hinge seat, regardless of the positioning of the lock slider.

While guaranteeing a safe operation of the door, avoiding the voluntary or inadvertent release of the latter in relation to the cabinet, this prior art construction requires the provision of stop means made of quite resistant materials and having a complex and relatively expensive construction so as to operate within the safety standards required for the operation of the door during the whole useful life of the appliance to which it is applied.

Object of the Invention It is a generic object of the invention to provide a safety device for the hinges of a cabinet door of the type considered herein, presenting a strong and extremely simple construction of relatively low cost and which prevents the door from being detached from the cabinet by the lock slider being deliberately or inadvertently displaced to the median position after the door has been opened at one of the sides thereof.

Summary of the Invention The present safety device is applied to a hinge arrangement for a cabinet door, comprising: a pair of hinge seats affixed close to each of the upper and lower ends of one of the parts defined by the door and the cabinet, symmetrically in relation to the center line of the latter, at their right and left end portions, respectively; hinge pins affixed to the other part defined by the door and the cabinet and to be each fitted in a respective hinge seat upon the closing of the respective side of the door; a lock

slider mounted to each one of the upper and lower ends of the door or cabinet part that carries the hinge seats and which can be displaced in opposite directions from a median position, said lock slider being provided, at its opposite ends, with cam portions which are arranged so that in the initial opening phase of the door at one side, the hinge pin of this side actuating on the adjacent cam portion causes the displacement of the lock slider to lock the hinge pin of the other side of the door in the interior of the respective hinge seat.

According to the invention, the safety device comprises a stop means incorporated to each hinge seat and which can be displaced between an inoperative position, which is reached upon the closing of the respective side of the door and in which said stop means allows the lock slider to be displaced to a locking position of the respective hinge pin, and an operative position, which is reached after a certain initial opening degree of the respective door side and in which said stop means prevents the lock slider, which is found displaced to a locking position of the opposite hinge pin, from being displaced to an unlocking position of the latter.

In a preferred constructive form of the invention, each stop means is constantly and resiliently forced to its operative position and displaced to the inoperative position by actuation of a respective drive means operated upon the closing of the respective side of the door.

With the constructive arrangement mentioned above, after the door has been opened at one of the sides thereof, by a sufficient angle to allow the user to access the positioning pin or the orifice that gives access to the V-shaped cut of the lock slider, the

upper and lower stops means of the other side of the door are maintained in their inoperative position, by action of the respective hinge pins, in which they allow the upper and lower lock sliders to remain locking the hinge pins of the closed side of the door, while the upper and lower stop means of the side of the door being opened are liberated to be resiliently displaced to the operative position, preventing the lock sliders from being displaced back to the unlocking position of the hinge pins under operation, even if the lock slider is unduly forced to move to its median position, from which said non-opened side of the door can be detached from the cabinet if pulled by the user.

Brief Description of the Drawings The present invention will be described below, with reference to the enclosed drawings, given by way of example and in which : Figure 1 is a schematic upper plan view of the lower hinge arrangement of the present invention, with the door in the closed position; Figure 2 is an enlarged detail of part of figure 1, with the lock slider being partially cut at the end turned to the side of the door that will be maintained articulated to the cabinet in a desired opening operation, for better illustrating the positioning of the respective stop means; Figure 3 is a similar view to that of figure 1, but with the door partially open; Figure 4 is a similar view to that of figure 2, but illustrating the same elements in the already open door condition; Figure 5 is a similar view to that of figure 4, but illustrating the opposite end of the partially open door;

Figure 6 is a partially cut perspective view of a support plate, illustrating the respective stop means in the operative position, actuating against the adjacent end of the lock slider; Figure 7 is a schematic partial vertical sectional view of a hinge seat provided at one of the upper sides of the door or the cabinet, illustrating the respective stop means in the operative position and the respective hinge pin in a still open door position at the respective cabinet side.

Figure 8 is a similar view to that of figure 7, but illustrating the same stop means displaced to the inoperative position by actuation of the hinge pin upon the closing of the door; Figure 9 is a perspective view of one of the lower hinge seats operating as stop means in the inoperative position, with the lock slider in the door closed median position on both sides; Figure 10 is a similar view to that of figure 9, but illustrating the lock slider in a hinge pin locking position at said side of the door and in the hinge pin release position at the opposite side ; and Figure 11 is a similar view to that of figure 10, but illustrating the lock slider in an opposite limit position, liberating the stop means to return to the operative position upon the opening of the door at this same cabinet side.

Detailed Description of the Invention As mentioned above, the present hinge arrangement is particularly adequate to provide the coupling of doors, presenting an automatically reversible opening, to the cabinets of refrigerators or freezers.

The arrangement considered herein is of the type comprising four hinges on each door P, which are arranged in pairs in the upper part and in the lower

part of the door P, the hinges of each pair being provided close to the right and left end portions of the door, respectively, and symmetrically in relation to the longitudinal axis of the door P or of the front face of the cabinet G.

Each of said hinges comprises a hinge seat 10 which takes the form of a slot provided in a seat plate 1, horizontally affixed to the upper and lower ends of the door P or the cabinet G, said slot presenting an open end portion 11 turned to the front face of the cabinet G and a closed end portion 12, opposite to the open end portion 11 and in the form of a semicircle projecting from the lateral edges of the slot and whose radius is slightly larger than that of a respective hinge pin 20, which defines the other element of each hinge and which is affixed to the other part defined by the door P or the cabinet G, so as to be fitted in a respective hinge seat 10 upon the closing of the door, as illustrated in figures 1 and 2. The fitting of each hinge pin 20 inside the respective hinge seat 10 is made by the displacement of the former along the slot which defines the hinge seat 10.

To the same part defined by the door P or the cabinet G which carries the hinge seats 10 is mounted a lock slider 30, generally in the form of an elongated bar which is disposed parallel to the closing face plane of the part which carries it, so as to be capable of being linearly displaced in opposite directions and from a median position corresponding to a closed door position (figures 1 and 2).

Each end of the lock slider 30 is shaped to define a cam portion 31 in the form of an inclined slope, which remains seated against the respective hinge pin 20 in the door closed condition, as illustrated in figures 1

and 2. In this condition, in case the door P is simultaneously pulled outwardly at both right and left sides, the two opposite cam portions 31 will prevent the hinge pins 20 fitted into the respective hinge seats 10 from being released.

In order to open the door P, the user needs only to pull one of its sides away from the cabinet G, making the force of the two hinge pins 20 of said door side, exerted on the adjacent cam portions 31 of the two lock sliders 30, to cause the linear displacement of the latter towards the other side of the door-cabinet assembly, so that a locking portion 32 of the two lock sliders 30 is conducted to be positioned against the respective hinge pins 20, locking them against liberation from the respective hinge seats 10 and consequently maintaining the door P articulated to the cabinet G during its opening.

As it is known from the state of the art, each pair of hinge seats 10 is generally provided in a frame, at least partially tubular and in which a respective lock slider 30 is guided. This frame is preferably mounted to the upper and lower end portions of the door P, however, it should be understood that the mounting of the assembly formed by a pair of hinge seats 10 and by a lock slider 30 could equally be made at the upper and lower ends of the cabinet G, and in this case the hinge pins 20 are affixed to the door P.

In the figures of the enclosed drawings, the hinge pins 20 are affixed to the cabinet G, while the hinge seats 10 and the two lock sliders 30 are mounted to the door P, the description below being directed to this mounting option.

In order to allow the lock slider 30 to automatically and safely return to the median position after the closing of the door P, in which its cam portions 31

are again positioned against the respective hinge pins 20, it is medianly provided, in its longitudinal side turned to the front face of cabinet G, with a V-shaped cut 33, against which will be pressed a positioning pin 40, which in the illustrated embodiment is mounted to the guide frame of the lock slider 30 in an axially displaceable manner.

Thus, when one side of the door P is opened and the lock slider 30 is displaced to the opposite side, one of the sides of the V-shaped cut 33 will cause the displacement of the positioning pin 40 to the outermost portion of the V-shaped cut 33, whereby said positioning pin remains more salient in relation to the adjacent longitudinal side of the lock slider 30, as illustrated in figure 3.

When the door is returned to the closed position, the positioning pin 40 touches a surface of the cabinet at the end of the closing movement, so that, as soon as the cam portion 31 of the open end of the lock slider 30 reaches, together with the door, a position that is posterior to the fitting of the adjacent hinge pin 20 in the respective hinge seat 10, said positioning pin 40 forces the lock slider 30 back to the median position, resetting it to a new opening of the door from either of the right and left sides thereof.

While it is preferred that the positioning pin 40 be mounted in an axially sliding manner to the part that carries the hinge seats 10 and the lock sliders 30, it should be understood that said positioning pin 30 could be affixed to the other of said parts defined by the cabinet G and'the door P.

In either of the constructions mentioned above for the positioning pin 40, after the door P has been opened by a certain degree, such as that illustrated in figure 3, it is possible for any person to access the

V-shaped cut 33 of the lock slider 30, pressing the movable positioning pin 40, or using any other similar instrument, in order to exert a transversal force onto one of the sides of the V-shaped cut 33, so as to cause the displacement of the lock slider 30 to the median position, in which the application of the opening force on the articulated side of the door will cause, by action of the hinge pin 20 against the cam portion 31 of the lock slider 30, the additional displacement of the latter towards the open side of the door P, completely releasing the latter from the cabinet G.

In order to guarantee the lock slider 30 to move to the articulated side of the door P upon the closing thereof, each end of the lock slider 30 is further provided with a slope 36, arranged on the longitudinal side provided in the V-shaped cut 33 and which, by touching a hinge pin 20 upon the closing of the respective side of the door P, forces the lock slider 30 to be displaced to the other side, allowing its passage by said hinge pin 20. Subsequently, the positioning pin 40, upon touching the other part of the door-cabinet assembly, forces the lock slider 30 to move back to the median position.

To prevent the door P from being detached from the cabinet G, the hinge, as described above, is further provided with a safety device which comprises a stop means 70, incorporated to each hinge seat 10, so as to operate jointly with the latter, being displaced between an operative position and an inoperative position, as described below.

In the embodiment illustrated in the drawings, each stop means 70 comprises a button 71 which is slidingly mounted in a housing 13 provided in the structure of the door P or in the seat plate 1 that carries the

pair of hinge seats 10 at one of the upper and lower ends of the door P. Each housing 13 is vertically aligned with a respective hinge seat 10 and projects to the interior of the door P, from the plane of the hinge seat 10, as better illustrated in figures 2,4, 5 and 11.

The dimensioning of each button 71 is made in such a way as to allow it to be vertically displaced between an inoperative position, illustrated in figures 8-10, in which it remains lodged inside the housing 13, in a position internal to the plane of linear displacement of the lock slider 30, allowing the latter to be displaced to a locking position of the respective hinge pin 20, when the door P is closed at both sides or only at the side in which said locked hinge pin 20 is found operative. The four buttons 71 are displaced to an inoperative position, housed inside the respective housing 13 or simply spaced back in relation to the operational displacement path of the respective lock slider 30, when the door P is found closed at both sides, allowing the lock slider 30 to be taken to the median position, by action of the positioning pin 40, remaining in conditions to be displaced to one side, to lock the hinge pin on this side, when the door is opened by the other side.

When the door P, upon being opened at one of the sides, reaches a certain opening degree, the upper and lower buttons 71 of the opening side are conducted to the operative position, projecting partially outwardly from the respective housings 13 and towards the interior of the adjacent hinge seats 10, in order to be positioned in the path of the respective lock sliders 30, which with the beginning of the effective opening of the door P, are fully displaced to the opposite side, so as to lock the hinge pins 20 which

maintains the door P articulated. With the displacement of the upper and lower buttons 71 of the opening side to the operative position illustrated in figures 7 and 11, the upper lock sliders are prevented from returning to the median position that liberates the hinge pins 20 under operation, even if the user voluntarily or inadvertently tries to displace any of the lock sliders 30 to the opposite end operational position, which unlocks the respective hinge pin 20, allowing the door P to be detached from the cabinet G.

It should be understood that the description above and the one cited below also refer to a constructive arrangement in which the hinge seats 10 and the lock sliders 30 are carried by the cabinet G and not by the door P.

In the illustrated embodiment, which uses the housings 13 for the buttons 71 of the stop means 70, the latter are constantly resiliently forced to the operative position, preferably by a spring element 75 mounted in the interior of the housing 13, the displacement of the buttons 71 to the inoperative position being achieved against the action of the respective spring elements 75. The housing 13 is provided with a limiting step 13a, against which is seated a tab 70a incorporated to the button 71, when the latter reaches the operative position. It is possible to construct the stop means 70 in other manners, such as for example in the form of elements that are resiliently deformable to the inoperative position.

In this case, the spring element 75 is incorporated to the button 71, forming a single piece therewith.

As illustrated, the button 71 is provided with an end portion, defining a slope 72 on which actuates a drive element attached to the cabinet G and which, in the illustrated embodiment, takes the form of the hinge

pin 20 itself, as shown in figures 7 and 8. However, it should be understood that the drive element of the stop means could be defined by any other element carried by one of the parts defined by the cabinet G and the door P and which acts on the stop means 70, conducting it to the inoperative position whenever the respective side of the door P reaches a closed or almost closed condition.

When one side of the door P that has been opened is returned to the closed position, at the final phase of the closing movement of this same side, the respective hinge pins 20 (or other corresponding drive elements) actuate on the slope 72 of the (upper and lower) buttons 71, initiating the displacement of the latter to the inoperative position, until the final closing of the side of the door P has been reached, when the buttons 71 reach the inoperative position (see figure 8), allowing both the (upper and lower) lock sliders 30 to be displaced to the median position by actuation of the upper and lower positioning pins 40.

As it can be noted, the constructive solution proposed herein allows providing the present reversible hinge system with the necessary operational safety to avoid the door from being unduly released from the cabinet, without requiring changes or reinforcements in the hinge means, which can be maintained with a simple design and not vulnerable to the wear of the elements during the useful life of the equipment.

It should be understood that the present hinge arrangement could be further provided with a support element to support the weight of the door P in the final closing phase and which is preferably affixed to the cabinet G, in order to cooperate with a lower surface portion of the door P, from a certain closing condition of the latter, as described and illustrated

in said prior patent document of the same applicant.

While only one embodiment of the invention has been illustrated, it should be understood that changes in the form and arrangement of the elements that compose the hinge arrangement and the safety device could be made without departing from the constructive concept defined in the claims which accompany the present description.