Domestic appliance having a door monitoring device

Abstract

A household appliance includes a compartment, a door for closing the compartment, a non-movable part, and a door monitoring apparatus including a contact pair which has two contact parts. One of the two contact parts is arranged on the door and the other one of the two contact parts is arranged on the non-movable part of the household appliance.

Claims

1. A household appliance, comprising: a compartment; a door for closing the compartment; a non-movable part; and a door monitoring apparatus including a contact pair comprising two contact parts, with a first contact part of the two contact parts being arranged on the door and a second contact part of the two contact parts being arranged on the non-movable part of the household appliance, wherein the two contact parts of the contact pair contact one another when the door is in a closed state and form a pair of plug-in contacts, and wherein at least one of the first contact part of the two contact parts or the second contact part of the two contact parts, or a combination thereof, includes an annular groove.

2. The household appliance of claim 1, wherein the door monitoring apparatus includes precisely one of said contact pair.

3. The household appliance of claim 1, wherein the two contact parts of the contact pair are each connected to an electrical line, with the electrical line of the first contact part of the two contact parts being routed through the door.

4. The household appliance of claim 1, wherein at least the second contact part of the two contact parts includes multiple contact surfaces which are electrically separated from one another, and electrical lines which are connected to the multiple contact surfaces.

5. The household appliance of claim 1, wherein the door monitoring apparatus includes two of said contact pair, with the door-arranged ones of the contact parts of the contact pairs being electrically connected to one another.

6. The household appliance of claim 1, wherein the non-movable part is a door flange.

7. The household appliance of claim 1, wherein at least one of the two contact parts is configured to have a predetermined fracture point.

8. The household appliance of claim 1, wherein the door monitoring apparatus includes an evaluation circuit, which is electrically connected to at least one of the two contact parts, so as to monitor an open state of the contact pair.

9. The household appliance of claim 1, constructed in a form of a PEF (Pulsed Electric Field) household appliance.

10. The household appliance of claim 1, wherein one of the first contact part and the second contact part comprises the annular groove, and wherein the other of the first contact part and the second contact part comprises a circular rib configured to be plugged into the annular groove when the door is in the closed state.

11. The household appliance of claim 10, wherein the first contact part comprises the circular rib and the second contact part comprises the annular groove.

12. The household appliance of claim 10, wherein the one of the first contact part and the second contact part includes one or more contact mating surfaces arranged on one or more side walls of the circular rib, wherein the other of the first contact part and the second contact part comprises a first contact surface and a second contact surface formed in a complementary manner with respect to the one or more contact mating surfaces of the one of the first contact part and the second contact part, and wherein the first contact surface and the second contact surface of the other of the first contact part and the second contact part are arranged on one or more side walls in the annular groove.

13. The household appliance of claim 12, wherein the first contact surface and the second contact surface of the other of the first contact part and the second contact part comprise annular contact surfaces arranged on opposite side walls in the annular groove.

14. The household appliance of claim 1, wherein the at least one of the first contact part or the second contact part, or the combination thereof, further comprises a central hole.

15. The household appliance of claim 14, wherein one of the first contact part and the second contact part comprises the central hole, and wherein the other of the first contact part and the second contact part comprises a pin-shaped protrusion configured to be plugged into the central hole when the door is in the closed state.

16. The household appliance of claim 15, wherein the first contact part comprises the pin-shaped protrusion and the second contact part comprises the central hole.

17. The household appliance of claim 15, wherein the one of the first contact part and the second contact part includes a first contact mating surface and a second contact mating surface, wherein the other of the first contact part and the second contact part comprises a first contact surface and a second contact surface formed in a complementary manner with respect to the first contact mating surface and the second contact mating surface of the one of the first contact part and the second contact part, wherein the first contact mating surface of the one of the first contact part and the second contact part is arranged on a side wall of the circular rib and the second contact mating surface of the one of the first contact part and the second contact part is arranged on a side wall of the pin-shaped protrusion, and wherein the first contact surface of the other of the first contact part and the second contact part is arranged on a side wall in the annular groove and the second contact surface of the other of the first contact part and the second contact part is arranged on a side wall of the central hole.

18. The household appliance of claim 14, wherein one of the first contact part and the second contact part includes one or more contact mating surfaces, wherein the other of the first contact part and the second contact part comprises a first contact surface and a second contact surface formed in a complementary manner with respect to the one or more contact mating surfaces of the one of the first contact part and the second contact part, and wherein the first contact surface of the other of the first contact part and the second contact part is arranged on a side wall in the annular groove and the second contact surface of the other of the first contact part and the second contact part is arranged on a side wall of the central hole.

19. The household appliance of claim 1, wherein one of the first contact part and the second contact part comprises the annular groove and further comprises a central hole, wherein the other of the first contact part and the second contact part comprises: a circular rib configured to be plugged into the annular groove when the door is in the closed state, and a pin-shaped protrusion configured to be plugged into the central hole when the door is in the closed state.

20. The household appliance of claim 19, wherein the first contact part comprises the circular rib and the pin-shaped protrusion, and wherein the second contact part comprises the annular groove and the central hole.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above-described characteristics, features and advantages of this invention and the manner in which these are realized become clearer and more explicitly understandable in conjunction with the following schematic description of an exemplary embodiment that is further explained in conjunction with the drawings.

(2) FIG. 1 shows as a sectional illustration in a side view a simplified sketch of a household appliance having a compartment, which can be closed by means of a door, and a door monitoring apparatus in accordance with a first exemplary embodiment with the door in the closed state;

(3) FIG. 2 shows as a sectional view in a side view the household appliance shown in FIG. 1 with the door in an open state;

(4) FIG. 3 shows in a front view a section of a household appliance in the region of a door monitoring apparatus in accordance with a second exemplary embodiment with the door in the closed state;

(5) FIG. 4 shows in a front view a section of a household appliance in the region of a door monitoring apparatus in accordance with a third exemplary embodiment with the door in the closed state;

(6) FIG. 5 shows in an oblique view a possible constructive embodiment of one of the two contact parts of the door monitoring apparatus in accordance with the second exemplary embodiment; and

(7) FIG. 6 shows as a sectional illustration in a side view a sketch of contact parts, which are hidden one inside the other when the door is in the closed state, with one of the contact parts in an embodiment in accordance with FIG. 5.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE PRESENT INVENTION

(8) FIG. 1 illustrates as a sectional illustration in a side view a simplified sketch of a household appliance 1, for example of a PEF cooking appliance or of a microwave appliance, having a treatment compartment (compartment 2) for food that is to be cooked and said treatment compartment can be closed by means of a door 4 that can pivot about a door hinge 3. The household appliance 1 has moreover a door monitoring apparatus having a contact pair 6, 7, comprising a first (door) contact part 6, which is arranged on the door 4, and a second (non-movable) contact part 7, which is arranged on a non-movable part of the household appliance 1 in the region of a flange 8.

(9) The two contact parts 6, 7 are each connected to an electrical line 9 or 10, wherein the electrical line 9 of the door contact part 6 is routed through the door 4 and further in the region of the door hinge 3 into the body of the household appliance 1. The two electrical lines 9, 10 are connected to an evaluation circuit 11 of the door monitoring apparatus.

(10) The evaluation circuit 11 is configured so as to detect whether or not the two contact parts 6, 7 are connected to one another. For this purpose, it is possible to apply a voltage via the electrical lines 9, 10 and detect an associated current I: if the current I is flowing through, it is possible to conclude from this that the two contact parts 6, 7 are connected to one another, if the current I is not flowing through, it is possible to conclude from this that the two contact parts 6, 7as illustrated in FIG. 2are separated from one another. Based on the detection of the contact state of the two contact parts 6, 7, the household appliance 1 can switch off or allow the switching-off of safety-critical components of the household appliance 1, such as a magnetron, a PEF pulse generator etc., for example by means of the evaluation circuit 11 or a control facility (not illustrated) that is connected thereto.

(11) The door monitoring apparatus therefore comprises in this case the two contact parts 6 and 7, the evaluation circuit 11 and the associated connection lines 9 and 10.

(12) FIG. 2 illustrates the household appliance 1 with the door 4 in the open state, in which the two contact parts 6, 7 are separated from one another. In this case, current I is not flowing through the contact parts 6, 7 and consequently also not flowing through the electrical lines 9, 10.

(13) The household appliance 1 can be reliably operated by way of example under the flowing scenarios: a) If the previously opened door 4 is closed, the two contact parts 6, 7 contact one another in the proper state and the closed state of the door 4 can be correctly detected by means of the evaluation circuit 11. b) If the contact parts 6, 7 do not contact one another when the door 4 is in the closed statefor example in the event of a malfunctionalthough it is incorrectly detected by means of the evaluation circuit 11 that the door is in the open state, it is not however relevant for safety in terms of monitoring the door 4. In such a case, the user can call customer services, for example. c) If the previously closed door 4 is opened, the two contact parts 6, 7 always separate from one another and the open state of the door is correctly detected. d) If the two contact parts have become so greatly stuck together (for example are welded to one another) that, when an attempt is made to open the door 4, they do not separate from one another, they prevent the door 4 from being opened. The safety of the household appliance 1 consequently remains preserved. The user notices that the door 4 cannot be opened and can then, for example, switch off the household appliance 1 and/or call customer services. e) If a user opens the door 4, which initially cannot be opened owing to sticking contacts 6, 7, by using force and/or with the aid of tools (for example using a cooking spoon as a lever to open the door), the contact parts 6, 7 are torn away from one another and consequently separated, and the switching function is re-instated. In this case, it is irrelevant as far as safety considerations are concerned if the household appliance 1 is thereafter defective since its safety remains preserved. If at least one of the contact parts 6, 7 is designed with a predetermined breaking point, current I no longer flows through even if the door 4 is subsequently closed.

(14) FIG. 3 illustrates in a front view a section of a household appliance 12 with the door 15 in the closed state. The household appliance 12 is designed in a similar manner to the household appliance 1 but has two contact pairs 6, 7 and 13, 14. The contact pair 6, 7 is designed as in the household appliance 1, wherein its non-movable contact part 7 is likewise connected to the evaluation circuit 11 via the electrical line 10. The second contact pair 13, 14 has in a similar manner a third door contact part 13 and a fourth non-movable contact part 14 that is arranged in the region of the flange 8. In a similar manner to the first contact pair 6, 7, the door contact part 14 is connected to the evaluation circuit 11 via an electrical line 16. The first contact part 6 and the third contact part 13 are electrically connected to one another, by way of example via metal components of the door 15, or, as illustrated, via a dedicated electrical line 17. If the door is in the closed state, the evaluation circuit 11 detects that a current I is flowing through both contact pairs 6, 7 and 13, 14 (connected electrically in series). If even only one of the contact pairs 6, 7 or 13, 14 is open, current I does not flow through. This exemplary embodiment provides the advantage that the operational safety is further increased: if the contact pairs 6, 7 and 13, 14 are located, for example, at different corners of the door 15, then it is possible to take into consideration the case that a user uses force to bend the door open the door at one corner and then the associated contact parts 6, 7 or 13, 14 are separated from one another at least at that site. The door monitoring apparatus has still further advantages in comparison to the door monitoring apparatus shown in FIG. 1 and FIG. 2.

(15) The evaluation circuit 11 is exclusive to the non-movable contact parts 7, 14, so that it is possible to forego an electrical line 9 through the door 15 or through metal components of the door 15. In turn, such a current flow only in the household appliance 1 outside the door 15 provides inter alia the following advantages:

(16) It is avoided that the current 1 is guided directly through the door hinge 3 with its possibly fluctuating electrical resistance, as a result of which in turn it is avoided that contact is incorrectly detected, in particular in the case of a mechanically worn out door hinge 3.

(17) A further advantage is that, if an electric consumer (for example a control panel, not illustrated) provided in the door 15 is to be supplied with energy, it is possible via the door hinge 3 or via a line 9 in the region of the door hinge 3 to avoid an unfavorable current flow to the door contact parts 6 and 13 owing for example to a lack of space. It is also possible to prevent the electrical line 9 fracturing as a result of frequent mechanical loadings as the door 15 is opened and closed.

(18) The door monitoring apparatus comprises in this case the contact parts 6, 7, 13 and 14, the evaluation circuit 11 and the lines 10, 16 and 17.

(19) FIG. 4 illustrates in a front view a section of a household appliance 18 with the door 21 in the closed state. The door monitoring apparatus has a contact pair 19, 20 having a first door contact part 19 and a non-movable contact part 20 that is arranged in the region of the flange 8.

(20) In contrast to the household appliance 1, the non-movable contact part 20 has multiple (in this case: two) contact surfaces 22a, 22b that are electrically separated from one another and electrical lines 10 or 16 that lead to the evaluation facility 11 are connected to said contact surfaces.

(21) When the door 21 is in the closed state, the door contact part 19 acts as an electrical (short circuit) bridge between the two contact surfaces 22a, 22b, with the result that a current I can flow via the door contact part 19 between the contact surfaces 22a, 22b. As a consequence, it is possible, even when using only one contact pair 19, 20, to realize the same advantages as is the case with the household appliance 12.

(22) The function as an electrical bridge can be implemented by way of example so that mating contact surfaces 24a, 24b of the door contact part 20, which can make contact with the contact surfaces 22a, 22b, are surface regions of an electrically conductive, for example metal, component, for example metal piece. Alternatively, the mating contact surfaces 24a, 24b can be electrically separated from one another, as illustrated, and can be connected to one another via an electrical line 25.

(23) The door monitoring apparatus therefore comprises in this case the contact parts 19 and 20, the evaluation circuit 11 and the connection lines 10 and 16.

(24) FIG. 5 illustrates in an oblique view a possible constructive embodiment of one of the two contact parts 19, 20, in this case by way of example of the non-movable contact part 20, as a plug-in element of a plug-in connection or coupling of the two contact parts 19, 20 that are formed in a complementary manner. The non-movable contact part 20 has an annular groove 26 and a central hole 27. The two contact surfaces 22a and 22b are provided in the region of the annular groove 26.

(25) FIG. 6 illustrates as a sectional view in a side view a sketch of the two contact parts 19 and 20 that are hidden one inside the other when the door is in the closed state. The door contact part 19 has for this purpose a circular rib, which can be plugged into the annular groove 26, and a pin-shaped protrusion that can be plugged into the central hole 27. The contact surfaces 22a and 22b are contacted by the mating contact surfaces 24a or 24b, wherein the mating contact surfaces 24a or 24b are electrically connected to one another, as indicated by the line 25. This plug-in connection or coupling is mechanically particularly stable and renders possible a reliable contact of the contact surfaces 22a and 22b with the mating contact surfaces 24a or 24b.

(26) Alternatively, the contact surfaces 22a, 22b can be provided as annular contact surfaces in the annular groove 26, for example in opposite-lying side walls. It is also possible for one of the contact surfaces 22a, 22b in the annular groove 26 to be present and the other of the contact surfaces 22b, 22a in the region of the hole 27. It is also possible to design the door contact part 19 as an integrally-formed metal part, with the result that it is possible to forego a dedicated line 25 or said door contact part is formed as such by the metal part. In this case, the mating contact surfaces 24a or 24b correspond to the surface region of the door contact part 19 that is brought into actual contact with the contact surfaces 22a, 22b.

(27) In general, the shape of the contact parts 19 and 20 can also be exchanged, i.e. that the door contact part 19 has the annular groove 26 and the hole 27 and the door contact part 20 has the circular rib, which can be plugged therein, and the pin-shaped protrusion.

(28) Also, the shape of the contact parts 19 and 20 in general is not limited to the illustrated annular groove-like shape but rather can have for example simple planar contact surfaces, pin-like contacts etc.

(29) Moreover, the contact pairs in general can also be used so as to supply consumers (for example control elements, displays etc.), which are provided in the door, with electrical energy via the contact pairs. For example, the consumers can be connected to the electrical lines 9 or 25 and supplied with energy via the current that is flowing therein.

(30) It goes without saying that the present invention is not limited to the illustrated exemplary embodiment.

(31) Thus, a single-pole circuit breaker is illustrated in the exemplary embodiments. However, it is possible, by suitably connecting multiple contact parts together or by suitably designed individual contact surfaces of a non-movable contact part, fundamentally to protect any number of poles. It is thus possible to provide a two-pole circuit breaker for simple power supply appliances and a three-pole or four-pole circuit breaker for three phase appliances. This applies in particular if the contact pair(s) is/are installed directly into a current circuit for these appliance components.

(32) In general, a, one etc. can be understood to mean a singular or plurality, in particular in the sense of at least one or one or multiple etc. as long as this is not explicitly ruled out, for example by the expression precisely one etc.