KR20090078797A - Blocking device for the door of an electric household appliance, in particular the door of a washing machine - Google Patents

Abstract

A blocking device (1) including a striker (5) in the form of a striker plate (5) sliding perpendicularly to the door (2) and adapted to cooperate in use with a notch (3) of the door (2), and a safety device (6) including a catch (7) blocking the sliding of the striker (5) and control means (8) including electrically operated actuating means (10) for selectively moving the catch (7) between an extracted position and a retracted position from/into its seat (11) in the safety device, in which positions the catch (7) is adapted to respectively intercept/not intercept the striker (5); wherein the control means (8) include a first element (12) actuated by the actuator means so as to be mobile between a first and a second limit stop positions in a direction (P) perpendicular to that of movement (S) of the catch (7); and a bell crank (14) restrained so as to be oscillating on a plane parallel to direction (S) of movement of the catch (7), operatively connected with its first shorter arm (15) to the first element and with its second longer arm (16) to the catch, to receive from the first element (12) an oscillating movement so to shift the catch (7) between said extracted and retracted positions in response to a movement of the first element (12) between said second and first limit stop positions.

Description

BLOCKING DEVICE FOR THE DOOR OF AN ELECTRIC HOUSEHOLD APPLIANCE, IN PARTICULAR THE DOOR OF A WASHING MACHINE

The present invention relates to a blocking device for a door of a household appliance, in particular for a door of a front-loading washing machine.

The doors of the household appliance in which the washing cycle is carried out, in particular the doors of the drum washing machines, are blocked in the closed position by a blocking device with a safety device which is separated only at the end of the washing cycle and thus only when the appliance is not affected by water. It is known.

For example, safety devices known from Applicant's EP 1137030 are provided with a blocking latch, first, such that one end of the latch projecting to a position pulled out of a seat in the first body works with the striker of the door blocking device in use. Control means for selectively moving the latch between the pulled and pushed position in the seat of the body, the first body receiving the control means latch; The blocking device comprises a striker, and generally has the form of a striker plate in which the first body of the safety device is slidably moved by a snap-fastly fixable second body; The second body, on the one hand, next to the side of the door to be blocked, is fixable to the casing of the household appliance and is therefore suitable for the striker to work with the notch of the door in use.

The control means of the safety device is defined by a bimetal spring arranged near a positive temperature constant (PTC) resistive tablet; When the appliance is running, the electrical supply current heats the resistive tablet, the tablet heats the bimetal spring, snapping in place to take the latched out position, and the latched position in the pulled-out device itself. Engagement with the striker plate's perforation prevents slippage across the latter, thus preventing it from being released from the notch even if the user attempts to force the door to an open position.

Known devices of the type described above already have amplification mechanism of the movement of the bimetal spring to ensure sufficient stroke of the clasp, even if completely satisfactory, in the form of a striker plate longer than those currently available for the clasp. A need exists for a blocking device that provides a stroke of the blocking element of the striker.

It is therefore an object of the present invention, regardless of the type of control means, for doors of household appliances, in particular the blocking member of the striker, to be used (based on PTC tablets and bimetal springs or on any other available technology). To provide a blocking device for a door of a drum type washing machine, which is relatively long and at least provides a stroke within certain limits that can be predetermined during the design phase, the blocking device at the same time lower production and assembly costs, and Ensure dimension and high stability.

The present invention therefore relates to a blocking device for a door of a household appliance, in particular a door of a drum type washing machine, as described in claim 1.

In particular, the blocking device of the present invention is characterized in that the control means of the clasp are: selective between the pulled-in and pushed-in position of the seat, the clasp being adapted to not intercept / intercept the striker respectively. Electrically actuated mover means for moving the vehicle; A first element actuated by the mover means to be movable between the first and second stroke-end positions in a direction perpendicular to the direction of movement of the clasp; A bell crank constrained to make pendulum motion on a plane parallel to the direction of movement of the clasp, between the pulled and pushed positions in response to movement of the first element between second and first stroke-end positions. And a bell crank, operatively connected to the first element with a first short arm and to the clasp with a second long arm to receive pendulum motion to move the latch from the first element.

According to an aspect of the invention, the first element of the control means is a metal foil associated with a bimetal bistable knee-pad device that is controllable by PTC resistance and forms actuation means; The metal foil is arranged towards and away from the bottom wall of the first body which acts as a guide of the striker and, in use, in movement between the second and first stroke-end positions and vice versa. To change the distance from the bottom wall, it moves between the first and second stroke-end positions in a direction essentially perpendicular to the bottom wall of the first body.

The bell crank is constrained to a fulcrum whose axis consists of pins arranged parallel to the bottom wall of the first body as well as the direction of sliding of the striker and is integrally constrained to the first body; In addition, the first arm of the bell crank is arranged so as to face each other and is oriented parallel to the slip direction of the striker on opposite sides and the peripheral longitudinal edge of the metal foil facing the corresponding longitudinal peripheral edge of the bottom wall of the first body. Provide a free end defined by a pair of elastically deformable arms arranged to engage with; Finally, preferably, the second arm of the bell crank carries the clasp integrally, the clasp extending protruding from the free end of the second arm on the opposing band to the first arm, such that the bell crank has a first body. Provide an essentially Z-shape on the pendulum plane, oriented perpendicular to the bottom wall of the.

In this way, an extremely lightweight, highly stable and low-cost blocking device is obtained, in which the latch and the corresponding control means are made as an integrally-completed safety device to block the striker when the door is closed. So that in any case there is always a striker positioned between the bottom wall of the first body and a sliding device between the safety device, the integrally-completed safety device is in a second body constrained to the first body, for example It is possible to snap or to be housed within a specific part of the first body, which would provide a particularly compact layout of the device.

Furthermore, the stroke available for the clasp as a result is essentially independent of the entity of the stroke available for the mover means, which means that the stroke available for the clasp mainly depends on the ratio between the lengths of the two arms of the bell crank. Regardless of the type of mover means used, it makes the required strokes of the entity: they may be traditional PTC resistors or other types with bimetal bistable snapping mechanisms, which will be shown in the preferred embodiment described. Can be.

Further features and advantages of the present invention will become apparent from the following description of the non-limiting embodiment, with reference to the accompanying drawings.

1 is a schematic 3/4 front perspective view, partially from the top of the blocking device of the present invention, with portions removed and partially unfolded for ease of understanding;

2 and 4 are schematic views taken along cutting planes II and IV-IV of the device of FIG. 1 in a first operating position.

3 and 5 show the same schematic cross sectional view of the device of FIG. 1 shown in FIGS. 2 and 4, respectively, in a second operating position.

With reference to FIGS. 1 to 5, reference numeral 1 uses a handle 4 while rotating about a door 2, for example axis A, of a household appliance, which is known but not shown for the purpose of simplicity. In the closed position of the door 2 (FIG. 1) of the drum type washing machine, which has a notch 3 which can be operated, the blocking device is displayed as a whole.

The blocking device 1, in the form of a striker plate, refers to the striker 5, which, in use, slides perpendicularly to the axis of rotation A of the door 2 and is adapted to work with the notch 3 of the door in use. And a safety device, indicated in its entirety by the number 6, which, in turn (FIGS. 2-5), latches 7 to prevent slippage of the striker 5 and a seat in the safety device 6 A control means of the latch (8) comprising an actuation means (10) electrically actuated to selectively move the latch (7) between the pulled in and out of the (11) position; The latches 7 in the retracted and pushed positions are adapted to not intercept / lateralize the striker 5 respectively.

According to a first aspect of the invention, the control means 8 is schematically shown in the figure with an arrow P, perpendicular to the direction of movement of the clasp 7, schematically shown in the figure with an arrow S. A first element 12 actuated by the actuator means 10 to be movable between the first and second limit stop positions (shown respectively in FIGS. 2 and 3 respectively) in the correct direction; And a bell crank 14 constrained to pendulum on a plane parallel to the direction S of movement of the clasp 7, the first between second (FIG. 3) and first (FIG. 2) limit stop positions. The pendulum motion is moved by the first element 12 to move the latch 7 between the pulled (FIGS. 3 and 5) and pushed (FIGS. 2 and 4) positions in response to the movement of the element 12. And a bell crank 14, which is operatively connected to the first element 12 with the first short arm 15 and to the clasp 7 with the second long arm 16 to receive from.

The device 1 comprises a first body 20 which is fixable in a known manner to the casing of the household appliance, beside the side of the door 2 to be blocked and on the opposite band of the rotation axis A of the door; The first body 20 carries, in a known manner, slidingly 5 a striker 5 in the form of a striker plate, the striker defining a slip guide for the striker 5 and defining the notch 3. Arranged between the safety device 6 and the bottom wall 21 of the first body 20 with a through opening 22 for it.

In particular, the clasp 7 of the device 6 is essentially parallel to the bottom wall 21 of the body 20 and in the direction S inside the through sheet 11 of the safety device 6. Arranged to move, the direction S being essentially parallel to the first longitudinal edge 25 of the striker 5 which is oriented parallel to the slip direction N of the striker 5 itself and the bottom wall of the body 20. It is arranged adjacent to the corresponding longitudinal peripheral edge 26 of 21.

As shown in more detail in FIG. 1, the longitudinal edge 25 of the striker 5 is oriented perpendicular to the bottom wall 21 of the first body 20 and the latch 7 in the pulled out position in use. The pin 30 which extends transversely to the slip direction N of the striker 5 is provided in place so that it may be suitable for being intercepted. As a suitable non-limiting example, a fin 30 is obtained integrally with a striker 5 formed by a metal plate in a single material, an appendix of the edge 25 of the metal plate. The plate is bent L-shaped out of its own laying plane.

According to the non-limiting embodiment described again, the safety device 6 is fixable to the bottom wall 21, on the band facing the bottom wall 21, to the body 20, for example. Within the second body 31, provided on one axis of the 20, is carried in a snap fastening manner and, in use, a through sheet for the bottom wall 21 of the first body 20 and for the clasp 7. 11 is arranged to face the longitudinal peripheral edge 26.

The bell crank 14 is formed by not only the bottom wall 21 of the body 20, but also by a pin 34 arranged in an axis parallel to the slip direction N of the striker 5. Constrained to, integrally constrained to the body 20, and suitably carried, by way of example, by opposing side walls of the body 31, which are snap fixedly constrained to the body 20.

According to the non-limiting example described, the first element 12 of the control means 8 is a bimetal bistable knee-pad device 40 controlled by the PTC resistor 41, which forms the actuation means 10. Is a metal foil 12 associated with; For example, the device 40 belongs to the type described in EP 1137030, in which the metal foil 12 is arranged facing away from the bottom wall 21 of the first body 20, and in use the first and First and second strokes in a direction P essentially perpendicular to the bottom wall 21 to change its distance from the bottom wall 21 in movement between the second stroke-end positions and vice versa. -Move between end positions.

The first and second stroke-end positions of the metal foil are, for example, by means of a contact 50 associated with the PTC resistor 41 (FIGS. 2 and 3) and the bottom wall of the first body 20, respectively. It is defined by the first and second shoulders facing 21 and integrally defined by the bottom wall 52 of the safety device 6, which is suitable as an example and forms an integral body of the second body 31.

According to the invention, however, unlike the device described in EP 1137030, the clasp 7 is carried directly by the foil 12, but indirectly by the foil 12, using the bell crank 14. Controlled. In particular, the first arms 15 of the bell crank 14 are arranged facing each other, oriented parallel to the slip direction N of the striker 5 and corresponding to the bottom wall 21 of the first body 30. A pair of elastically deformable arms 60 engaged on faces opposite the peripheral longitudinal edge 6 (FIGS. 4 and 5) of the metal foil 12 facing the longitudinal peripheral edge 26 (FIG. 4). 2 and 3) to provide a free end.

The second arm 16 of the bell crank 14 integrally carries the latch 7 which protrudes and extends from the free end of the second arm 16 on the opposing band to the first arm 15. The bell crank 14 will provide an essentially Z-shape on the pendulum plane, oriented perpendicular to the bottom wall 21 of the first body 20. In this way, the clasp 7 does not form a linear trajectory in movement between the pulled out and the pushed in position (and vice versa) and has a housing with a large clearance in the seat 11. To form a curved trajectory.

This is not an obstacle to the correct operation of the device 1, and in fact, due to the fact that working with the striker 5 takes place via the fin 30 of the striker 5, this is due to the device 1 itself. Increases the stability, miniaturization and readiness. However, if a linear movement of the clasp 7 is required, it is clear that it can be guided without a gap in the seat 11 and can only work together by contact with the free end of the arm 16.

The operation of the device 1 is apparent from the figures of the accompanying figures. When the actuator means 10 is operated (using a contact 70 arranged through the slots 72 in the body 31, in the case of use, the resistor 41, as appropriate) the foil 12 is From the position in FIG. 2 to the position in FIG. 3, the clasp protrudes from the seat 11, making the pin 30 of the striker 5 approach the edge 26, which slides adjacently in the pulled out position. The master produces a rotation of the lever 14. This movement, whose amplitude depends on the ratio between the lengths of the arms 15 and 16, causes the clasp to intercept the trajectory of the pin 30, thus freeing the striker 5 from free sliding (usually against the bias of the spring). Thus, if the notch 3 is engaged with the striker 5 (FIG. 1) in a known manner, for example through the striker's perforation 80 (FIG. 1), the door 2 is blocked in the closed position. Enough to make it work.

When the household appliance stops working, no resistor 41 is provided and the gradual cooling of the resistor 41 snaps the foil 12 back to the position of FIG. 2 after a certain predetermined time; This movement returns the latch 7 to the pushed position of FIGS. 2 and 4, thus creating the opposite rotation of the crank bell 14, which frees the pin 30 and the striker 5.

The blocking member of the striker is relatively long and can be predetermined at least in advance during the design phase, regardless of the type of control means used (based on PTC tablets and bimetal springs or on any other available technology). To provide a blocking device for the door of a household appliance, for the door of a drum type washing machine, which provides a stroke within the limits, which at the same time ensures low production and assembly costs, small dimensions and high stability Awards are available.

Claims (10)

A striker 5 in the form of a striker plate which slides perpendicularly to the axis of rotation A of the door 2 in use and adapted to work with the notch 3 of the door in use, Electrically actuated to selectively move the latch 7 between the latch 7 which blocks slippage of the striker 5 and between the pulled and pushed in / out position of the seat 11 in the safety device 6 The safety device 6 comprising the control means 8 of the clasp comprising the actuation means 10 Doors of household appliances, in particular drum-type washing machines, in which the latch 7 in its pulled and pushed positions is adapted to not intercept / intercept the striker 5, respectively. As blocking device 1 for The control means 8 also comprises a first element actuated by the actuator means 10 so as to be movable between the first and second stroke-end positions in a direction P perpendicular to the direction of movement of the clasp 7. 12); The pendulum motion is moved by the first element 12 to move the latch 7 between the pulled and pushed positions in response to the movement of the first element 12 between the second and first stroke-end positions. Parallel to the direction of movement S of the clasp 7, operatively connected to the first element 12 with the first short arm 15 and to the clasp 7 with the second long arm 16 so as to receive therefrom. Further comprising a bell crank (14) constrained to perform pendulum motion on one plane. The device of claim 1 comprising a first body (20) fixable to the casing of the household appliance, beside the side of the door (2) to be blocked and on the band opposite the axis of rotation (A) of the door, The first body 20 defines a slip guide for the striker 5 and between the safety device 6 and the bottom wall 21 of the first body having a through opening 22 for the notch 3 of the door. A blocking device, characterized in that for slidingly carrying said striker (5) in the form of a striker plate located at. The striker 5 according to claim 2, wherein the latch 7 is oriented essentially parallel to the bottom wall 21 of the first body and parallel to the slip direction N of the striker 5 itself. A corresponding longitudinal periphery of the bottom wall 21 of the first body 20, arranged to move inside the through sheet 11 of the safety device in a direction S essentially perpendicular to the first longitudinal edge 25. Blocking device, characterized in that arranged adjacent to the edge (26). 4. The first longitudinal edge (25) of the striker (5) is oriented perpendicular to the bottom wall (21) of the first body (20) and according to the latch (7) in the pulled out position. And a pin (30), which extends across the slip direction (N) of the striker (5) in place so as to be suitable for interception in use. The safety device (6) according to claim 3 or 4, wherein the safety device (6) is fixable to the first body (20) on the band facing the bottom wall (21), and the through sheet (11) of the latch (7). ) Is carried in a second body 31 provided on one side, which is arranged to face the longitudinal peripheral edge 26 of the bottom wall 21 of the first body 20 in use. , Blocking device. 6. The bell crank 14 is not only parallel to the bottom wall 21 of the first body, but also parallel to the slip direction N of the striker 5. Blocking device, characterized in that it is constrained to a fulcrum formed by a pin (34) arranged axially and integrally constrained to the first body (20). The bimetal bistable knee-pad device according to claim 2, wherein the first element of the control means is controlled by a PTC resistor 41, which forms the actuation means 10. Metal foil 12 associated with 40); The metal foil 12 faces away from and away from the bottom wall 21 of the first body 20 and between the first and second stroke-end positions and vice versa positions in use. To change between the first and second stroke-end positions in a direction P essentially perpendicular to the bottom wall 21 of the first body in order to change the distance from the bottom wall 21 in the movement of The blocking device, characterized in that arranged. 8. The bottom wall (21) of the first body according to claim 7, wherein the first and second stroke-end positions of the metal foil (12) are respectively associated with the contact portion (50) associated with the PTC resistor (41). Blocking device, characterized in that it is defined by first and second shoulders defined by a bottom wall (52) of a safety device (6) facing and integral with it. 9. The first arm (15) of the bell crank (14) according to claim 7 or 8, facing each other and arranged to engage the peripheral longitudinal edge (61) of the metal foil (12) on opposite sides. A free end defined by a pair of elastically deformable arms 60, wherein the metal foil 52 is oriented parallel to the slip direction N of the striker 5 and the first body Blocking device, characterized in that it faces the corresponding part of the longitudinal peripheral edge (26) of the bottom wall (21) of. 10. The method according to any one of claims 1 to 9, wherein the second arm (16) of the bell crank (14) carries the clasp (7) integrally, the clasp being the bell crank (14) of the first one. Free end of the second arm 16 on the band facing the first arm 15 to provide a Z-like shape essentially on its pendulum plane of motion oriented perpendicular to the bottom wall 21 of the body. And protruding from and extending from the blocking device.

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