A safety device for accessible chambers, particularly in ovens

Safety device for an internal chamber accessible in particular from a cooking appliance

The invention relates to a safety device for an accessible internal chamber, capable of being closed by a door and, in particular, for a cooking appliance, where the door can be brought, by a device operable from outside the chamber. internal chamber by means of an operating handle, in an open position allowing access to the internal chamber, a closed position preventing access to the internal chamber, an unlocking position where the closed door is unlocked and a locking position where the closed door is locked, and where the door can be brought from the internal chamber, thanks to the safety device, at least in the unlocked position.

Various security devices for doors are known in the existing art. For example, GB 2 154 646 A discloses a safety mechanism, i.e. an emergency deactivation mechanism, for doors of cargo containers, transport motor vehicles and the like. This emergency deactivation mechanism allows a person who is unintentionally locked up, for example inside a container or a motor vehicle, to be able to open the container door from the inside. For this, there is provided on the outer side of the door an operating rod which can be turned using a handle and the end of which carries a locking projection which engages with locking devices. provided on the door frame, so that the rotation of the operating rod by means of the handle allows the door to be locked from the outside. When the door is locked, the handle is inside a receiving device which can be detached from the inside of the door. If necessary, a person can thus detach the receiving device from the door and access the handle to rotate the handle and therefore the operating rod, whereby the door is unlocked. However, this arrangement has the drawback that the door cannot be opened from the inside when a person is maliciously locked in, and the locking mechanism is blocked from the outside.

Also known, thanks to EP 0 959 208 A1, is a safety device making it possible to unlock a door, for example from a climatic chamber. This device makes it possible to move a receiving device for a handle integral with an operating rod from the internal side of the door, in order to cause a rotation of the operating rod and, consequently, an unlocking of the door. However, this device has the same drawbacks as that of GB 2 154 646 A, namely that the unlocking of the door can be prevented by blocking the closing mechanism from the outside.

Furthermore, from US Pat. No. 6,022,056 an automated device for controlling the closing of a snap-in door is known, which is incorporated into a frame of the door and which controls an arrangement of locking bars of the door. This arrangement has a spring loaded locking bar and a free locking bar which allows locking by the spring loaded locking bar. The system is designed so that the two bars are controlled one after the other to open the door. The disadvantage of this arrangement is that it is very expensive to produce.

The aim of the present invention is to provide a safety device of the type described for an accessible internal chamber, in particular for a cooking appliance, which makes it possible to overcome the drawbacks of the prior art and which, in particular, makes it possible to open the door of an internal chamber from the internal side even when the locking mechanism operated from the outside is blocked, and this with means of a simple design.

This object is achieved, according to the invention, thanks, in particular, to the fact that a movable locking stop, which is located in particular on a wall of the internal chamber, inside or outside it. ci, and by which the door can be brought, from inside and / or outside of the internal chamber, from the locking position, in which the locking stop is engaged with a lock which cooperates with the operating handle , to the unlocked position and to the fact that a deactivation device allows a person, inside the internal chamber, to move the blocking stop actively and / or passively to unlock the door.

It is conceivable here that the deactivation device is actuated mechanically and / or pneumatically by means of at least one operating element in the form, for example, in the form of a lever, of a button that can be pulled. , a cable that can be pulled, a push-button, a wheel that can be turned, an element arranged in particular on the bottom of the internal chamber, capable of moving in at least one spatial direction and preferably having the shape of a grid and / or the like; by means of at least one transmission element, such as for example a rod, a fork-shaped part, a drive part, a traction cable, a gear, a pulley and / or the like.

In addition, provision is made according to the invention for the deactivation device to operate magnetically by making use of at least one permanent magnet and at least one electromagnet, the permanent magnet being preferably placed on the locking stop.

A preferred embodiment of the invention is characterized by the presence of at least one detector for detecting the presence of a person in the internal chamber, in the form of a motion detector, of a detector. infrared, a weight detector (preferably a steel wire extensometer), a reed relay and / or a microswitch disposed inside the internal chamber; and / or a monitoring and / or command device, where the detector and / or the monitoring and / or command device cooperate or cooperate with the deactivation device.

An alternative embodiment of the safety device according to the invention is characterized in that at least one spring device exerting a thrust on the locking stop, allows the door to be brought - when no person is present in the door. the internal chamber - in its unlocked or locked position.

Provision can also be made, according to the invention, for the locking stopper to be placed outside the internal chamber, for the deactivation device to be located at least in part inside the internal chamber and for the stopper to be placed inside the internal chamber. blocking cooperates with the deactivation device inside the internal chamber through a wall of the internal chamber or of the door, in particular by means of a shaft which passes through the wall or the door, preferably in a sealed manner, thanks to a lip ring with spring. -. ·

Provision can be made, according to the invention, for the locking stopper to be able to be moved by means of an electric motor and, in particular, by means of the shaft.

Preferably, according to the invention, an emergency power supply is provided, for example in the form of a battery, a rechargeable photovoltaic cell and / or a rechargeable accumulator, preferably cooperating with the deactivation device. , the detector and / or the monitoring and / or command device.

Provision can also be made for the locking stopper and the latch to have a complementary shape at the level of their respective regions of engagement and, in particular, for them to have congruent angled surfaces.

Provision can also be made for an element arranged in the internal chamber, in particular an actuating element, to be produced in the form of a removable tool making it possible to break a window of the door and / or to force the door. .

Finally, the safety device according to the invention can be characterized in that it comprises a display unit capable of indicating the presence of a person in the internal chamber, in particular in the closed position and / or in the locked position of the door, preferably producing an alarm signal, in particular of an acoustic and / optical nature, where the display unit can preferably cooperate with the detector, the deactivation device and / or the control device and / or the control device.

The invention is based on the surprising discovery that a safety device can be realized in such a way that an opening, in particular a door of a cooking chamber of a cooking appliance, can also operate when the locking mechanism. Lock provided on the outer side of the cooking chamber door is locked so as to keep the cooking chamber door in the locked position. In this safety device, a locking stop which ensures the engagement of the locking mechanism in the locking position, can be deactivated thanks to a deactivation device which allows to bring the door of the cooking chamber into the unlock state. An apparatus comprising a man-sized internal chamber and which comprises a safety device according to the invention can also be used for many applications, for example it can be used in penitentiary establishments and the like.

Other characteristic features and advantages of the invention will become apparent on reading the following detailed description of preferred embodiments of the invention, given by way of example and made with reference to the accompanying schematic drawings. In these drawings:

<td>figure 1</td><td>is a front view of a cooking appliance with the cooking chamber closed and a first embodiment of a cooking device. security according to the invention;</td>

<td>figure 2</td><td>is a top view of the apparatus of Figure 1;</td>

<td>figure 3</td><td>is a view of a detail (part A) of FIG. 1;</td>

<td>figure 4</td><td>is a view of a detail (part B) of FIG. 2;</td>

<td>figure 5</td><td>is a front view of a cooking appliance with a chamber of open cooking and a second embodiment of the device for safety of the invention;</td>

<td>figure 6a</td><td>is a view of a detail of a third embodiment of the safety device of the invention with a locking stop in a position unlocking;</td>

FIG. 6b is a view of a detail of the third embodiment of the safety device of FIG. 6a, with the locking stop in a position

<td>figure 7</td><td>locking; is a partial front view of a cooking appliance with a fourth embodiment of the safety device according to the invention, .....- · ...... '' - :, j partly in section; and</td>

Figure 8 is a sectional view of the fourth embodiment of the device

-safety according to figure 7, following line D - D. -i. · -,

FIG. 1 shows a cooking appliance 1 with a safety device 3 according to a first embodiment of the invention. The safety device 3 comprises a locking stop 5 and an operating handle 7 for opening and closing a door 9 of a cooking chamber, from the external side of the cooking appliance 1. Furthermore, the door 9 of the cooking chamber, which is shown in the closed and locked position, has an inspection window 11.

Figure 2 is a top view of the cooking appliance 1 of figure 1. The reference numerals correspond to those of figure 1. In this figure, the reference 9 'indicates the door of the cooking chamber , which is in its open position. Furthermore, it emerges from Figure 2 that the cooking appliance 1 comprises a cooking chamber 13 and an emergency power supply in the form of a photovoltaic cell 15. As for the safety device 3, it comprises a deactivation handle 17 inside the cooking chamber 13.

We will now explain the operation of the first embodiment of the safety device of the invention, with reference to Figures 3 and 4 and which constitute detailed views of the safety device 3 of parts A and B of Figures 1 and 2.

In Figures 3 and 4, the cooking chamber 9 is shown in a locked state. In this locked state, the locking stopper 5 engages with a lock 19.

The locking of the cooking chamber 9 can be done in two ways. The operating handle 7 can be in its unlocked position during the closing of the door 9 of the cooking chamber. When the door 9 of the cooking chamber is in the closed but unlocked position, the operating handle 7 and therefore the latch 19, may come ...

in their locked position, where the latch 19 engages with the locking stopper 5 in the locked position and the door 9 is locked. If, on the other hand, the operating handle 7 and therefore the latch 9 are already in the locked position when closing the door 9, the locking stop 5 is designed in such a way that it is temporarily brought out of the locking position shown in Figures 3 and

4. To this end, both the latch 19 and the blocking stop 5 have corresponding chamfered surfaces, so that, during the closing of the door 9 of the cooking chamber, the blocking stop 5 is moved against the bias. a spring device 21, out of the locked position and then returns to the locked position under the effect of the force produced by the spring device 21 as soon as the door 9 of the cooking chamber is closed to engage with the latch 19 and thus lock the door 9 of the cooking chamber.

To open the door 9 of the cooking chamber, turn the operating handle 7, so as to disengage the latch 19 from the locking stop.

5, which makes it possible to move from the locked position to the unlocked position. When the latch 19 is disengaged from the locking stopper 5, the door 9 of the cooking chamber is unlocked and can be brought into its open position.

Provision is made for the operating handle 7, after the operation of unlocking and opening the door 9, to automatically return to the locking position shown in FIG. 3 or in FIG. 4, by the effect of a spring device (not shown).

The door 9 of the cooking chamber can also be opened by a person who is in the cooking chamber 13, thanks to the deactivation handle 17 which is integral with a shaft 23 which passes through a wall 25 of the cooking chamber. The through opening for the shaft 23 in the wall 25 of the cooking chamber is sealed with a sealing ring 27, for example a lip ring with a spring or a ring for a motor shaft. In this way, the cooking chamber 13 of the cooking appliance 1 can operate, in the event of cooking with steam, substantially without this steam escaping therefrom. At the end of the shaft 23 adjoining the deactivation handle 17, there is a fork-shaped piece 29 through which the shaft 23 is coupled with the locking stop 5. When a person is standing. in the room of_{: (}cooking 13 and that it turns the deactivation handle 17 in the direction of the arrow in figure 3, while the door 9 of the cooking chamber is locked, the locking stop 5 is moved out of the locked position by the movement of the shaft 23 and the fork-shaped piece 29. At this time, the latch 19 is disengaged from the locking stopper 5 and the door 9 of the cooking chamber is unlocked from the inside, so that 'it can then be opened. This unlocking takes place independently of the position in which the operating handle 7 and therefore the latch 19 is located, and it therefore takes place even when the operating handle 7 is in the locked position. Under these conditions, when the door 9 of the cooking chamber is in the closed position and the operating handle 7 is in the locking position, the safety device 3 allows, despite everything, to open the door 9 of the cooking chamber.

Provision can also be made for the deactivation handle 17 to be removably mounted on the shaft 23 and for the deactivation handle 17 to be able to be used to break the inspection window or as a tool in the event that the door 9 of the cooking chamber would be obstructed, for example by a piece of furniture: at this time, the deactivation handle 17 can serve as a lever to force open the door 9 of the cooking chamber.

In Figure 5, there is shown a second embodiment of the safety device according to the invention, indicated here by 3 '. The references here correspond to those of Figures 1 to 4. Unlike the first embodiment of the safety device 3, the second embodiment of the safety device 3 'does not include any deactivation handle 17. Instead, the shaft 23 cooperates with a traction cable 31, which in turn cooperates via a pulley 33 with the support 35 of a grid 37 disposed on the bottom of the cooking chamber. 13. In the event that a person is trapped in the cooking chamber 13, it would be possible for him to cause a rotational movement of the grid 37. This movement would be communicated via the traction cable 31 to the safety device 3 'and this would have the effect of withdrawing the locking stop 5 from its locking position towards the unlocking position and therefore an unlocking of the 9 'door of the baking chamber. It can also be arranged that not only a rotational movement of the grid 37 results in a withdrawal of the locking stopper 5, but also a horizontal or vertical movement of the grid 37, in particular a vertical movement of the grid. 37 caused by a force resulting from the weight of the user coming to walk on the grid 37: at this moment, the user locked in the cooking chamber 13 does not need to actively cause the operation of the safety device 3 ', this operation is provoked passively. It is also conceivable that the movement of the grid 37 is communicated to the safety device 3 'by means of a rod (not shown).

In Figures 6a and 6b, there is shown a third embodiment of a safety device according to the invention, indicated here by 3 ”. The same components in this third embodiment as those of the first two embodiments are indicated by the same reference numerals. This 3 ”safety device also includes a locking stop 5 'and a 2Γ spring device. In addition, a permanent magnet 39 is disposed on the blocking stop 5 'and an electromagnet 41 is disposed near this permanent magnet. FIG. 6a illustrates the unlocking position of the locking stopper 5 ', which prevails when the electromagnet 41 is not supplied with current. The spring device 21 'urges the locking stop 5' towards the unlocking position in which the latch 19 cannot come into engagement with the locking stop. This ensures that the cooking chamber 9 cannot be locked in the event of an interruption in the current supply. On the other hand, if an electric current flows through the electromagnet 41, the magnetic interaction between the electromagnet 41 and the permanent magnet 39 results in the locking stopper 5 'being moved - as shown in fig. 6b - against the bias of the spring device 21 towards the locking position, in which the latch 19 is engaged with the locking stop 5 '.

To unlock the door 9 of the cooking chamber 13, provision can be made for the person locked in the cooking chamber 13 to be able to use a switch or the like to act actively on the current flow ίο in the electromagnet to unlock the baking chamber door 9. In addition, provision can be made for the unlocking of the door 9 of the cooking chamber to take place passively. For this, the electromagnet 41 cooperates with a control device (not shown) which, moreover, cooperates with a detector (not shown). When this detector determines that a person is in the cooking chamber 13, the current flow to the electromagnet 41 is interrupted and the locking stopper 5 'is pushed by the spring device 21' into. the unlocking position shown in Figure 6a. As a detector, it is possible to use in particular an electrical switch (microswitch or a reed relay) which is placed on the floor of the cooking chamber 13 and which is actuated by a deformation of the bottom of the cooking chamber caused by the force due to the weight of the person present.

In one embodiment of the invention of the safety device according to the invention (not shown), a spring device retains a locking stop with a permanent magnet in its locking position. When an electric current flows through the electromagnet, the interaction between the electromagnet and the permanent magnet results in a displacement of the locking stop out of the locked position and towards the unlocked position. To prevent unlocking of the cooking chamber from being made impossible when the main power supply to the cooking appliance 1 is interrupted, provision is made for the safety device and the control device associated with it to be able to be activated. supplied from an emergency power source, in this case taking, for example, the form of a photovoltaic cell 15.

In Figures 7 and 8, there is shown a fourth embodiment of the safety device according to the invention, indicated here by 3 '”. Here, a deactivation handle 17 'is provided on the side of the wall 25 directed towards the cooking chamber 13. This deactivation handle 17 cooperates with a shaft 23 'which passes through the wall 25 of the cooking chamber and which is connected to a drive part 43 mechanically cooperating with a fork-shaped part 29' to which a stopper is coupled. 5 ”locking applied by a 21” spring device.

Deactivation of the 3 '”safety device is carried out as follows.

If a person is in the cooking chamber 13, in order to deactivate the - 3 ”'safety device, that person can turn the deactivation handle 17' in the opening direction 45. This causes a rotational movement of the. shaft 23 'and, consequently, a displacement of the drive part 43. The action exerted by the drive piece 43 on the fork-shaped piece 29 causes a displacement of the fork-shaped piece 29 'and consequently a displacement of the locking stop 5 ”in the direction of unlocking 47. The locking stopper 5 ”is then moved against the bias of a spring device 21” (spring acting in pushing) out of the locking position shown in Figures 7 and 8, to an unlocking position. As the 5 ”locking stop in the unlocked position of a cooking chamber door (not shown in figures 7 and 8) no longer offers a grip, the cooking chamber door can be opened by the person. located inside the cooking chamber 13, by operating the deactivation handle 17 '.

The characteristic elements of the invention, as they emerge from the description given above as well as from the claims, can be used for the implementation of the invention in its various embodiments, either in isolation or in one embodiment. any combination