Patent Publication Number: US-9885515-B2

Title: Refrigeration appliance with movable front panel

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority, under 35 U.S.C. § 119, of German application DE 10 2016 202 614.3, filed Feb. 19, 2016; the prior application is herewith incorporated by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a refrigeration appliance, in particular a cupboard-shaped refrigeration appliance such as a combined fridge/freezer, in which a movable front panel, e.g. a pull-out drawer, closes off a lower part of the appliance. A refrigeration appliance of this type is known from published, European patent application EP 2 113 621 A1. 
     In order to secure the drawer in its closed position, this known appliance has a securing element protruding beyond a front face of an appliance body or carcass, in which two latch parts spread apart by a spring are retained in a pivotable manner. A complementary securing element of the drawer contains two pins, which rise up from an upper edge of the drawer and engage behind the latch parts in a closed position of the drawer. When the drawer is pulled out and when it is pushed back into the closed position, the pins press the latch parts against one another counter to the force of the spring. This means that the drawer is secured in the closed position, but not protected from unauthorized access. Furthermore, the securing elements protruding beyond the upper edge of the drawer and the front face of the body are disruptive during use, as an item of clothing of a user could catch on them. 
     Locking systems for the doors of refrigeration appliances have been proposed on several occasions, such as in German utility model DE 29 504 813 U1 or U.S. patent publication No. 2008/0066506A1. These two make provision for protrusions overhanging the front face of the body, in order to be engaged into a latch thereon or to anchor it there. 
     SUMMARY OF THE INVENTION 
     The object of the invention is to specify a refrigeration appliance with a drawer, which enables a locking of the drawer, without requiring prominent protrusions which obstruct the use of the refrigeration appliance. 
     The object is achieved in a refrigeration appliance with a body, which can be closed off in an upper part by at least one door and in a lower part by a movable front panel, by the front panel being lockable in the closed position by a latch, which engages into a fitting part supporting the door. 
     The fitting part does also protrude beyond a front face of the body according to a preferred embodiment, yet as it supports the door, it is almost entirely concealed by the door and is thus extremely inconspicuous. Furthermore, there is no possibility for the clothing of a user to become entangled on the fitting part. 
     According to a preferred embodiment, the front panel is part of a drawer which is received in the lower part of the body such that it can be pulled out. 
     The front panel can also, however, be a door leaf. 
     In order to ensure an effective locking of the door leaf, an axis of the door leaf and the fitting part are preferably spaced far apart from one another, arranged on two opposing side walls of the body. 
     The latch is preferably electrically driven. 
     The latch should be able to be actuated by a supply voltage in the lower voltage region. On one hand, small format drives are available for this voltage range, which can be simply integrated into the front panel; on the other hand, simple, cost-effective measures for preventing the penetration of moisture into the drive of the latch may suffice if the supply voltage is low enough that a user himself is not endangered if direct contact is made with a surface conducting the supply voltage. 
     The latch should be retained by a permanent magnet in a position engaging into the fitting part and/or a position retracted into the front plate; the application of the supply voltage can then be limited to the short time periods during which the latch is moved. This minimizes the energy consumption of the latch drive. In addition, even when moisture reaches voltage-carrying surfaces, there is only a low risk of damage by electrolytic corrosion. 
     If, as already mentioned above, the fitting part protrudes beyond a front face of the body, the front panel can impact against the front face in the closed position. 
     Above the front panel, two doors are preferably hinged on opposing side walls of the body. Thus, in the case of the embodiment with the door leaf, one of the doors can be pivotable about the same axis as the door leaf, and the latch can engage into the fitting part of the other door. 
     In the embodiment with the drawer, two latches can be arranged on the front panel, in order to engage into fitting parts of the two doors. A tilting of the drawer thus can be prevented, should a user attempt to pull it out in spite of the locking. 
     The latch can expediently be controlled by a sensor, which responds to the reaching of the closed position of the front panel. 
     The sensor can interact with a control unit, which is configured to bring the latch into a position engaging into the fitting part when the sensor signals the reaching of the closed position of the front panel, and thus to automatically lock the front panel when a user has brought it to its end stop against the body. 
     Alternatively or additionally, the control unit can be configured to retain the latch in a position retracted into the front panel, so long as the sensor signals that the front panel is not located in the closed position. This is important in order to prevent a collision of the latch with the fitting part, which could lead to damage to the latch or the front panel. 
     An operating element for controlling the latch can be arranged on a front face of the front panel. 
     Alternatively or additionally, the latch can also be controlled wirelessly, in particular by an RFID transponder or an application which runs on a mobile phone, another mobile device or a computer of a user communicating with the control unit via a—preferably wireless—network. 
     Control of the latch via a fingerprint scanner is also taken into consideration. 
     Other features which are considered as characteristic for the invention are set forth in the appended claims. 
     Although the invention is illustrated and described herein as embodied in a refrigeration appliance with a movable front panel, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. 
     The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         FIG. 1  is a diagrammatic, perspective view of a refrigeration appliance according to the invention; 
         FIG. 2  is a partial, perspective view of an enlarged detail of the refrigeration appliance; 
         FIG. 3  is a sectional view of a drive and control of a latch; and 
         FIG. 4  is a perspective view of a second embodiment of the refrigeration appliance. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the figures of the drawings in detail and first, particularly to  FIG. 1  thereof, there is shown a perspective view of a cupboard-type domestic refrigeration appliance according to the invention. Doors  1 ,  2  are hinged on the front edges of side walls  3  in an upper part of the appliance body or carcass  4 . The doors  1 ,  2  close off a storage chamber extending across the entire width of the body  4 , typically used as a normal refrigerator compartment, in the upper part. A second storage chamber  5 , typically a freezer compartment, is located in a lower part of the body  4 . A drawer  6  is received by the second storage chamber  5 . 
     The drawer  6  is shown in  FIG. 1  in an open position pulled out from the storage chamber  5 . It contains a front panel  7  provided with a heat-insulating filling, side walls  8 , a rear wall  9  and a bottom panel  10 . In the closed position of the drawer  6 , only the side walls  8 , the rear wall  9  and the bottom panel  10  are inserted into the storage chamber  5 . The front panel  7  is wider than the storage chamber  5  and, in the closed position, rests with its rear face against the front edges of the side wall  3 , which form the front face  11  of the body  4 . 
     In each case, a fitting part  12  anchored to the body  4  in an immovable manner can be seen on the upper face of the doors  1 ,  2 . A mirror-inverted fitting part  13 , concealed in  FIG. 1 , engages onto the lower face of the doors. One of these is shown in an enlarged view in  FIG. 2 . It contains a base plate  14  fastened, e.g. screwed, so as to rest against the front face  11 , from which a flat support arm  15  protrudes forward. At the point of the support arm  15 , a hinge pin  16  projects vertically upward and is provided to engage into a hinge bush on the lower face of the door  2  and thus, together with a complementary hinge pin of the upper fitting part  12 , to define the pivot axis of the door  2 . 
     If the drawer  6  is located in the closed position, the support arm  15  extends closely beyond an upper face  17  of the drawer  6 . Embedded into this upper face, below each fitting part  13 , is a locking component group  18 , the structure and function of which will be explained on the basis of  FIG. 3 . Belonging to the locking component group  18  is a vertically movable latch  19 , which in  FIG. 2  is shown dashed as it is mostly concealed below the support arm  15 . Only a point of the latch  19 , which engages into a bore hole  20  of the support arm  15  from below, can be seen directly, in order to lock the drawer  6  in the closed position. 
       FIG. 3  shows a vertical section through the locking component group  18 . Here, the latch  19  is located in a retracted, unlocked position, in which its point is flush with the upper face  17 . The point is located in a bore hole  21  of a cover plate  22  of the locking component group  18 . The cover plate  22  is made of permanent-magnetic metal, on one hand in order to form a robust bracket for the latch  19  which is unaffected by forces from the lateral direction, when the latch  19  protrudes beyond the upper face  18  in the locked position (shown dashed in  FIG. 3 ), and on the other hand in order to hold the latch  19  stable in the raised locked position by interacting with an iron core  23  embedded in the latch  19 . 
     A coil  24  surrounds the latch  19  in a position which lies above the iron core  23  in the unlocked position and below the iron core  23  in the locked position. Thus, the coil, when a short current impulse is applied to it, can both accelerate the latch upward from the unlocked position, so that its iron core  23  enters the magnetic field of attraction of a cover plate  22  and is drawn into the locked position by magnetic force. If the latch  19  is located in the locked position, the same current impulse causes a downward force, which releases the latch  19  from the locked position and allows it to fall into the unlocked position. 
     The voltage of the current impulse amounts to 12 V here. 
     The source of the current impulse is a control unit  25 . The control unit  25  is coupled to a sensor for detecting the position of the latch. The sensor can be the coil  24  itself, to which a weak current is applied by the control circuit  25  which is not sufficient to drive a movement of the latch  19 , but which enables a measurement of the inductance of the coil  24 , from which value the position of the latch  20  can be inferred. The control unit is further coupled to a sensor  26 , which is configured to detect whether the drawer  6  is located in its closed position or not. The sensor  26  can, for example, be a switch on the rear face of the front panel  7 , which is actuated by contact with the front face  11 . 
     So long as the drawer  6  is not closed and the latch  19  is located in the unlocked position, the generation of a current impulse, through which the latch  19  could be displaced into the locked position, is excluded. If the signal of the sensor  26  reverses and shows that the drawer  6  is located in the closed position, a current impulse is generated, in order to bring the latch  19  into the locked position. 
     Should the detection of the latch position show that the locked position was not achieved, the current impulse can be output once more. If this occurs a number of times without success, then there may be provision for a warning signal to be output for the user. 
     An operating element  27 , by means of which the unlocking can be triggered, is preferably attached to a front face of the drawer  6 . To protect against unauthorized access, the operating element  27  can be embodied as a fingerprint scanner or as a keypad, which only responds to the input of a predefined button combination, which the user can preferably define. 
     Furthermore, a radio interface  28  can be provided, which responds e.g. to the presence of an RFID tag carried by the user or an item of authentication information transmitted by a smart phone or another mobile device of the user. There may be provision that, when the radio interface  28  of the control unit  25  indicates the presence of an authorized user, it brings the latch  19  into the unlocked position, so that the user can access the drawer  6  at any time, as if it were not secured. As soon as the radio interface  28  loses contact with the RFID tag or the mobile device of the user, which implies that the user is no longer in the surrounding area of the refrigeration appliance, the control unit switches the latch  19  back into the locked position. 
     Alternatively, if the radio interface  28  is provided for verifying the authentication of a user, a simple button which the user presses to unlock the drawer, suffices as operating element  27 . The control unit  25  subsequently attempts to respond to an RFID tag or a mobile device of the user via the radio interface  28 . If this is successful, then this is considered to be proof that the user is in the vicinity and the drawer  6  is unlocked. If no response is received from the RFID tag or mobile device, then the drawer remains locked. 
     A permanent magnet may also be arranged on the fitting part  13  instead of in the cover plate  22 . Thus, in the raised position the latch  19  is only stable when it is held firmly by the permanent magnet in the bore hole  20  of the fitting part  13 ; if this is not possible, because the drawer  6  is not located in the closed position, then the latch  19  always falls back into the unlocked position. 
       FIG. 4  shows a second embodiment of the refrigeration appliance in a perspective view analogous to  FIG. 1 . The front panel  7  is embodied here as a door leaf, which can be pivoted about a pivot axis  29  shared with the door  1  from the shown open position into a closed position resting against the front face  11  of the body  4 . The locking component group  18  is embedded into the upper face  17  of the front panel  7  on its end facing away from the pivot axis  29 , so that its latch  19  can engage into the fitting part of the opposing door  2  from below. 
     The following is a summary list of reference numerals and the corresponding structure used in the above description of the invention:
           1  Door     2  Door     3  Side wall     4  Carcass     5  Storage chamber     6  Drawer     7  Front panel     8  Side wall     9  Rear wall     10  Bottom panel     11  Front face     12  Fitting part     13  Fitting part     14  Base plate     15  Support arm     16  Hinge pin     17  Upper face     18  Locking component group     19  Latch     20  Bore hole     21  Bore hole     22  Cover plate     23  Iron core     24  Coil     25  Control unit     26  Sensor     27  Operating element     28  Radio interface     29  Pivot axis