EP1442169A1

EP1442169A1 - Door latch

Info

Publication number: EP1442169A1
Application number: EP02787544A
Authority: EP
Inventors: Günter Hengelein; Hubert Harrer
Original assignee: Ellenberger and Poensgen GmbH
Current assignee: Ellenberger and Poensgen GmbH
Priority date: 2001-11-08
Filing date: 2002-11-02
Publication date: 2004-08-04
Anticipated expiration: 2022-11-02
Also published as: EP1442169B1; DE10154850C1; DE50208084D1; DE20216614U1; ES2271354T3; US6886868B2; CA2450212C; CZ20033324A3; PL366929A1; CA2450212A1; ATE338843T1; PL193794B1; WO2003040457A1; US20040140677A1

Abstract

A door latch is particularly suited for a washing machine door. The device has a pivotally mounted rotary catch for latching onto a locking element and a pivotally mounted blocking or arresting element. The latter is pivotally mounted between a latching position that latches the rotary catch and an unlatching position that releases the rotary catch. The arresting element can be actuated by a bimetallic adjusting element, which can be heated by a heating element, and by an actuator system that, at the same time, is actively connected to the turning catch in a direct manner. A torque component effected on the arresting member by the actuator system is greater in value that a torque component introduced by the bimetallic adjusting element.

Description

Description door lock

The invention relates to a door lock, in particular for a washing machine door, with a pivotably mounted rotary latch for locking a locking element and with a pivotably mounted inhibiting element which can be pivoted between a locking position locking the rotary bolt and an unlocking position releasing the rotary bolt.

Such a door lock is e.g. known from DE 198 34 844 C2. In this case, a pawl is provided to block the inhibitor, which can be actuated by an electromagnet. Due to a large number of effective levers, a force acting on the closing element in the opening direction up to the point of engagement of the pawl on a blocking surface of the blocking element is considerably reduced. However, there is no provision for a mechanism that becomes effective in the event of a power failure and takes safety-related aspects into account.

A door lock for a washing machine door, which shows a defined behavior in the event of a power failure, is known, for example, from DE 199 15 669 A1. During washing machine operation, a bimetallic spring washer is heated by an electrical heating element, the spring washer being connected to a rocker which can block or release a locking slide of the door lock via a securing element. At the start of the washing process, the bimetallic spring washer is heated so that after a warming-up phase of the spring washer, the swing arm is actuated and the door lock is blocked in the closed position. After the washing process has ended, the door lock remains blocked due to the heated bimetal spring washer. This effect, which is also effective in the event of a power failure, serves to prevent the washing machine door from opening too early, particularly when the drum is running. After the spring washer has cooled, the door lock is released again. The predefined blocking time during which the door lock remains blocked must be designed in such a way that the door lock remains blocked for a sufficiently long time with every selectable washing program and every possible drum loading. Due to this non-variable locking time, there are operating modes in which the door lock remains blocked for an unnecessarily long time. A door locking device for washing machines or laundry drying machines, in which the time during which the locking remains blocked after the washing or drying process has ended, is known, for example, from EP 0 384 148 B1. The blocking of the locking device depends on characteristic sizes of the machine such as the temperature and the level of the washing bath and the speed of rotation of the drum. However, safety requirements are not adequately met because there is no defined behavior in the event of a power failure.

The invention is based on the object of specifying a door lock, in particular for a washing machine door, which both enables controllable blocking and also has emergency locking properties independent of the energy supply.

This object is achieved according to the invention by the features of claim 1. Here, a door lock with a pivotably mounted rotary latch also includes a pivotably mounted inhibitor which can be actuated both by a bimetal control element which can be heated by a heating element and by an actuator system, the actuator system simultaneously being in operative connection with the rotary latch. The actuator system acts directly on the rotary latch, i.e. without going through the inhibitor. Due to the fact that the inhibiting element is operatively connected to both the actuator system and the bimetal control element, a construction with a small number of movable parts can be realized. The rotary bolt can be blocked in its locking position, for example a locking block of a washing machine door, by the actuator system and / or by the bimetal control element acting on the inhibiting element.

A torque can be exerted on the pivotably mounted inhibitor both via the actuator system and via the bimetal control element. According to a preferred embodiment, the torque that can be transmitted by the actuator system is greater than the torque that can be transmitted by the bimetal control element. In this way, the action of the bimetal control element can always be overridden by the controllable actuator system, provided that the power supply is undisturbed. In particular, after the washing program has ended, with the bimetal actuating element still heated, the blocking of the locking can be released as soon as this is possible without safety concerns due to the operating state of the washing machine and the actuator system receives a corresponding control signal.

The bimetal control element can be limited to a safety-related emergency function. In the event of a power failure and thus failure of the actuator system, the locking remains blocked until the bimetal control element has cooled down sufficiently and releases the rotary latch via a pivoting movement of the inhibiting element. Since this safety mechanism only comes into effect in the event of a power failure, a blocking time of the bimetal control element, which can include additional safety reserves, is not disadvantageous when the washing machine is operated as intended. A heating-up phase of the heating element and the bimetallic control element after the start of the energy supply is not relevant from a safety point of view, since the rotary latch can be blocked directly by the actuator system and blocking is therefore possible immediately after the washing machine door is closed.

A particularly simple design of the actuator system is preferably achieved by designing it as a double magnet system. With this design, a magnetic core can act directly on both the inhibitor and the rotary bolt. The interaction of the actuator system and the inhibitor can be designed in such a way that the actuator can pivot the inhibitor from its locking position to its unlocking position, but not vice versa. This means that only the bimetal adjusting element is provided for locking the inhibiting member, while both the bimetal adjusting element and the actuator system are provided for unlocking the inhibiting member.

In order to detect the position of the rotary bolt, an electrical locking contact is advantageously provided, which is closed, for example, when the rotary bolt is closed, that is to say the locking element is locked. Furthermore, in addition or as an alternative, according to a preferred embodiment, a door position-dependent contact system is provided, which is triggered by a door position-dependent slide regardless of the position of the rotary bolt. Both the electrical locking contact the door position-dependent contact system is also preferably connected to a machine control system, it also being possible to connect to a superordinate communication system, for example via an installation bus.

Manual unlocking of the inhibiting element and thus of the rotary latch is generally not necessary; this also applies to a power failure. However, in order to be able to unlock the inhibiting element after a shortened waiting time, for example after a power failure, an emergency release is provided according to an advantageous further development, with which the inhibiting element can be unlocked, even against the action of the bimetal control element.

The door locking device fulfills both mechanical and electrical functions. In order to do justice to these functions equally, the device according to a preferred embodiment includes a mechanically resilient metallic base plate, with which a drive unit made of plastic can be connected in a modular manner, which receives the electrical and electronic as well as electromechanical components. The modular structure means that a drive unit can be connected to various base plates, for example for different washing machine types.

A circuit board is advantageously provided for connecting the electrical, electronic and electromechanical components, such as door position-dependent contact system, electrical locking contact, heating element, bimetal control element and actuator system. The individual components can either be attached directly to the circuit board or connected to it, for example via plug contacts. The circuit board is also suitable for connecting a compact connector, via which both the lines for the energy supply to the door lock and the signal lines can be connected. The design of the door lock with a single compact connector makes installation easier compared to a device with several connections, while at the same time practically eliminating the risk of incorrect assembly. An embodiment of the invention is explained below with reference to a drawing. Show here:

1 is an exploded view of a door lock, Fig. 2 schematically shows a section through the door lock with the rotary latch open,

3 shows a section according to FIG. 2 with the rotary latch closed,

4 a section of a closing member and a slide,

5 shows an inhibitor in the unlocked position and, in sections, a rotary latch and an actuator system,

Fig. 6 u. 7 the inhibitor in the locked position,

Fig. 8 the inhibitor with emergency release spring, and

Fig. 9, the door lock in rear view.

Corresponding parts are provided with the same reference symbols in all figures.

Fig. 1 shows the door lock 1 with its essential components. A base plate 2 made of metal, for example die-cast zinc, can be connected, in particular screwed, to a housing 3 made of plastic which forms a drive unit. Likewise, the base plate 2 can be connected, in particular screwed, to a washing machine housing (not shown). Furthermore, the base plate 2 has a pin 5 held between two cheeks 4, on which a locking element or locking block 6 (FIG. 4) can engage. The locking block 6 also engages a slide 8 which is dependent on the door position and which is connected to a spring 9. The slider 8 penetrates the actuation side 10 of the housing 3, which is shown on the right. The spring 9 presses the slider 8 in the direction of the bolt 5. On both sides of the slider 8, microswitches 11 are arranged in the housing 3, which are parts of a contact position-dependent contact system 12 are.

In the housing 3, a rotary latch 13 is pivotally mounted on an axis of rotation 14. An actuator system 15 designed as a double magnet system is provided for actuating the rotary bolt 13. An upper coil 16 and a lower coil 17 are for Displacement of a substantially cylindrical magnetic core 18 is provided. A tapered area 19 of the magnetic core 18 penetrates a semicircular recess 20 of the rotary bolt 13. The tapered region 19 of the magnetic core 18 is adjoined by a head part 21 which, with its annular upper edge 21 ', connects to a semicircular support surface 22 of the rotary bolt surrounding the recess 20 13 can attack. The underside 23 of the head part 21 is provided for actuating an inhibiting element 24 which is pivotably mounted about an axis of rotation 25. The axis of rotation 14 of the rotary bolt 13 and the axis of rotation 25 of the inhibiting element 24 are parallel to one another in the exemplary embodiment. Deviating from this, the axes of rotation 14, 25 can also be arranged in different planes including an angle, in particular a right angle.

The inhibiting element 24 has an actuating arm 26 for actuation by the magnetic core 18, a blocking arm 27 for blocking the rotary bolt 13 and a fork arm 28 for receiving an end 29 of a bimetal actuating element 30. The bimetal actuating element 30 can be heated by a PTC (positive temperature coefficient) heating element 31, which bears directly on the bimetal actuating element 30. Contacts 32 are provided to supply energy to the heating element 31. A voltage is applied to the heating element 31 via the contacts 32 and the bimetal control element 30. All of the contacts 32 of the housing 3 which are led outwards are combined on its connection side 33 in a compact plug 34. The connections 32 of the compact plug 34 are connected to a printed circuit board 35 as a carrier for the electrical and electronic components. The circuit board 35 is located below a cover 36 of the housing 3.

The functions of the rotary latch 13 can be seen in more detail in FIGS. 2 to 4. The rotary latch 13 has a hook 37 protruding from the housing 3 on its actuating side 10, which engages under the washing machine with the door closed and the closing element 6 closed (FIG. 4) and thus blocks it. The locking member 6 is pivotable about a pivot point 38 and has a hook 39 which engages around the bolt 5, and a driver 40 which presses the slide 8 into the housing 3. In the open position of the rotary latch 13 (FIG. 2), a resilient locking contact 42 is separated from a fixed locking contact 43 by a contact arm 41. stands held. The locking contacts 42, 43, like the door position-dependent contact system 12, are connected to a control, not shown, which, for example, only enables the washing process to be started when the locking contacts 42, 43 are closed.

A return spring 44 designed as a helical spring, which is clamped between the actuator system 15 and the locking lever 13 in the region of the semicircular recess 20 and surrounds the magnetic core 18, exerts a force in the direction of the open position shown in FIG. 2 on the rotary latch 13. To close the rotary latch 13, the magnetic core 18 is tightened so that the return spring 44 is compressed. The inhibitor 24 has no function in this process. Without an energy supply, the bimetallic adjusting element 30 is prestressed in such a way that it presses the fork arm 28 of the inhibiting element 24 in the direction of a stop 45 which lies in the housing 3 opposite the actuating side 10. Torque acts clockwise on the inhibiting element 24. If the bimetal actuating element 30 is heated by the heating element 31, the bimetal actuating element 30 is deflected in the direction of the actuating side 10 and the inhibiting element 24 is thus rotated counterclockwise. An actuation of the rotary bolt 13 by the inhibitor 24 is not provided. The inhibitor 24 is only turned into the locking position by the bimetal control element 30 when the rotary bolt 13 has already been brought into the locking position by the actuator system 15 (FIG. 3). The actuator system 15 is designed as a double magnet system in order to be able to exert a controlled force on the magnetic core 18 in both directions. Alternatively, a simple magnet system with an appropriately designed spring for generating a force in the opposite direction can also be implemented.

When the inhibiting member 24 is pivoted into its locking position (FIGS. 3, 6, 7), the blocking arm 27 is positioned below a projection 46 of the rotary latch 13. The blocking arm 27 is axially offset relative to the actuating arm 26 with respect to the axis 25 of the inhibiting member 24. If the power supply to the actuator system 15 fails, the return spring 44 exerts a force on the rotary latch 13 in the direction of its open position, the blocking arm 27 blocking the rotary latch 13 in its closed position (FIG. 7) after only a very small adjustment path of the rotary latch 13 , The blocking arm 27 rests on the projection 46 in such a way that the Blocking a slight lifting of the rotary latch 13 against the action of the return spring 44 is required. In this way it is safely prevented that the blockage is released unintentionally, for example due to vibrations of the washing machine. The blocking is only released when the bimetal control element 30 cools down and presses the fork arm 28 of the inhibiting element 24 in the direction of the stop 45. Due to the design of the individual levers 13, 27, 28, only a small force that can be applied by the bimetal control element 30 without auxiliary energy is required for this.

In regular operation, with sufficient energy supply, the torque that can be applied to the inhibiting element 24 by the actuator system 15 via the magnetic core 18 and the actuating arm 26 is greater than the torque that can be applied to the inhibiting element 24 by the bimetal control element 30. This means that the controlled actuation of the rotary latch 13 by the actuator system 15 always prevails against the passively effective bimetal control element 30.

In order to be able to unlock the inhibiting element 24 even when the energy supply has failed and the bimetal control element 30 is still heated, an emergency release 48 (FIG. 8) comprising an emergency unlocking spring 47 is provided. The emergency release spring 47 has a spring winding 49 arranged concentrically about the axis of rotation 25 and an arm 50 formed thereon, which rests on a bar 51 of the housing 3. A projection 52 of the actuating arm 26 bears against the arm 50. A bracket 54 protruding from a rear wall 53 of the housing 3 (FIG. 9) is formed on the arm 50. The blocking of the inhibiting element 24 can be released by moving the arm 50 and thus the actuating arm 26 through a window 55 in the rear wall 53 of the housing 3, for example by means of a cable (not shown). The connection of the housing 3 to the base plate 2 by screws 56 can also be seen from FIG. 9. LIST OF REFERENCE NUMBERS

Door lock 28 fork arm

Base plate 29 end

Housing, drive unit 30 bimetal control element

Cheek 31 heating element

Bolt 32 contact

Locking device, locking block 33 connection side

Slider 34 compact connector

Spring 35 printed circuit board

Actuating side 36 cover

Microswitch 37 hooks door-dependent contact 38 pivot system 39 hooks

Quarter turn lock 40 driver

Axis of rotation 41 contact arm

Actuator system, double magnet sy42 Locking contact stem 43 Locking contact upper coil 44 Return spring lower coil 45 Stop

Magnetic core 46 projection tapered area 47 emergency release spring

Recess 48 emergency release

Headboard 49 spring turn upper edge 50 arm

Support surface 51 bar

Bottom 52 lead

Inhibitor 53 rear wall

Axis of rotation 54 plate

Operating arm 55 windows

Blocking arm 56 screws

Claims

Expectations

1. door / lock, in particular for a washing machine door, with a pivotably mounted rotary latch (13) for locking a locking member (6) and with a pivotably mounted inhibiting member (24) between a locking position locking the rotary latch (13) and one of the rotary latch (13) releasing unlocking position, characterized in that the inhibiting member (24) by a heating element (31) heatable bimetal control element (30) and by an actuator system (15), which is also in direct operative connection with the rotary bolt (13) stands, can be actuated.

2. Door lock according to claim 1, characterized in that the torque that can be transmitted from the actuator system (15) to the inhibiting element (24) is greater than the torque that can be transmitted from the bimetal control element (30) to the inhibiting element (24).

3. Door lock according to claim 1 or 2, characterized in that the actuator system (15) is designed as a double magnet system.

4. Door lock according to one of claims 1 to 3, characterized in that the rotary bolt (13) is in operative connection with an electrical locking contact (42, 43).

5. Door lock according to one of claims 1 to 4, characterized by a door position-dependent slide (8) which is operatively connected to a door position-dependent contact system (12).

6. Door lock according to one of claims 1 to 5, characterized in that the inhibiting member (24) is operatively connected to an emergency release (48).

7. Door lock according to one of claims 1 to 6, characterized by a with a base plate (2) modularly connectable drive unit (3).

8. Door lock according to claim 7, characterized in that the base plate (2) is formed from a metallic material.

9. Door lock according to one of claims 1 to 8, characterized by a printed circuit board (35) for connecting at least one of the components electrical locking contact (42, 43), door position-dependent contact system (12), heating element (31), bimetal control element (30) and actuator system ( 15).

10. Door lock according to claim 9, characterized by a with the circuit board (35) connected compact connector (34).