FR2682131A1 - DEVICE FOR IMMOBILIZING THE LOADING POSITION OF A LAUNDRY DRUM LOADED FROM ABOVE. - Google Patents

Abstract

The drive wheel (7) of the laundry drum of a top-loading washing machine carries a stop ring (9) provided with a stop notch (10) which cooperates with a stop (12) when the drum is in the loading position. The stop head (12) is part of a first arm of a link (20) with two arms actuated by the frame (17) of a device with a bistable electromagnet. A spring (24) keeps the link (20) in a stable position.

Description

i Device for immobilizing a drum in the loading position

  Top loading laundry The invention relates to a device for immobilizing a top loading laundry drum of a washing machine, device in which an electric motor drives a stop disc which is integral in rotation of the laundry drum, outside the laundry tub, and whose external profile includes a stop notch which, in the loading position of the laundry drum, coincides with a movable stop head

  linked to an electrically controlled drive device.

  A device of this type is disclosed by the patent application.

  European vet 347 393 In this device, the position of the stop head

  depends on the angle of rotation of a cam disc driven by a moto-

  reducer The stop head is constituted by a roller-feeler which, in

  loading position, falls into the stop but which counts

  bare of its shape is easily released from said stopper under the action of additional efforts Overall, the known device is very

  complicated and expensive and it also requires a mounting space re-

laterally important.

  The objective of the present invention is, in a device of the

  type described in the introduction, to minimize the expenditure in ma-

  material as well as the space required for mounting The device must

  be housed in a narrow space between a front wall of the tank

  and the outside wall of the body of a washing machine.

  The problem is solved according to the invention by the fact that the head

  is part of a first arm of a two-arm link which pre-

  feels two extreme pivoting positions kept stable by means of a spring and the second arm of which is connected to the frame of a

  electromagnet which acts in the direction of pivoting or tangential-

  The elements mentioned can be easily dis-

  laid flat on a mounting plate, so that the complete unit can be installed in the narrow space between the front face of a washing tub and the external casing of the washing machine The number of elements required for this device is very small and its mechanics is simple.

  Advantageously, the armature is connected by an articulation

  lation to the second arm This allows the electromagnet to be rigidly fixed to the mounting plate, which no longer necessarily follows the

pivoting movement.

  According to a preferred arrangement of the invention, the device

  bistable of the armature of the electromagnet is obtained by means

  of a spring which is stretched between a fixed point relative to the electroai-

  mant and a link point located on the side of the bearing

  rod opposite the fixed point so that, in both positions

  end of the link, the line of action of the spring force is located on different sides of the link bearing This type of assembly has a particularly small overall height because the angle of movement of the link is relatively small and born

not exceed 45 'maximum.

  In an embodiment of the invention particularly favorable in terms of the size of the device, in both

  extreme positions of the link, the armature is located in a posi-

  far away from the excitation position A pulse applied to a single coil electromagnet is sufficient to bring the rod into its other extreme bistable pivoting position passing through

neutral.

  According to a preferred embodiment of the invention,

  the electromagnet has two coils with corresponding action zones

  lay in the extreme positions of the frame The size of a

  electromagnet with two coils of this type remains relatively small; this-

  allows it to better control the action of the electromagnet on the posi-

  tion of the connecting rod only in the case of an electro-ai-

single coil mant.

  According to a particularly advantageous embodiment of

  the invention, the stopper is arranged in an elastic material Ce-

  this considerably reduces the jerk produced in the mechanism

  laundry drum drive mechanism when the stop head falls into the stop notch. An improvement of the invention which is particularly resistant to wear includes a stop disc the periphery of which is provided

  a wear-resistant surface with good sliding characteristics

  ment, the stop head also comprising a material with a reduced coefficient of friction compared to the peripheral surface Given

  that very often the stop head is applied to the peripheral surface

  that of the stop disc long before the stop notch is opposite said stop head, a surface with a lesser sliding characteristic would cause rapid wear of the stop head and possibly

of the stop disc.

  In order to further reduce the shock when the stop head falling into the stop notch disc, the peripheral surface, in an area located before the stop notch in the direction of rotation of the stop disc, is adapted to the material of the stopper so as to obtain a high coefficient of friction This allows, thanks to the high coefficient of friction, to reduce the relative speed between the stopper

  and the peripheral surface inside a delimited area before reaching

  dye the stop notch, so that the jerk caused by the fall of the

  stop head in the notch takes place with less energy.

  Additional jerk reduction can be achieved

  by providing an elastic torsional coupling between the rear disc

  drum and drum drive or the laundry drum.

  The invention is described below in detail using

  of an exemplary embodiment shown in the drawings These show

  trent: Figure 1, a drive side view of a laundry tub of a top-loading washing machine, Figure 2, part of Figure 1 showing details

  of arrangement of a device according to the invention, on a higher scale

re and

  Figure 3, a section along the line m-m I 1 of Figure 2.

  A laundry drum 5 driven by the belt

  drive wheel 4 and the drive pulley 7 is rotatably mounted in a laundry tub 1 of a top-loading drum washing machine on which a drive motor 2 is fixed using a

  fastening device 3 Motor side, the drive belt 4 steps

stand on a small pulley 6.

  Parts of an immobilizer 8 are fixed res-

  pectively on the laundry tub 1 and on the drive pulley 7.

  The part fixed to the drive pulley 7 is a stop disc which is in the form of a crown 9 linked to the rim of the drive pulley 7 The stop crown has a stop notch 10 which, after having traversed the angle oa with the drive pulley 7 in the direction of the arrow, is located just opposite the other part of the immobilization device, namely the stop head module 11 with its pivoting stop head 12 After having traversed this angle, the drum cover 13 (top left in the drawing) is perfectly aligned with the loading hopper 14 The drum is immobilized in this position.

  Figures 2 and 3 show in detail an example

  full realization of the immobilizer The module 11 includes

  takes a mounting plate 15 on which an electromagnet 16 is

  fixedly mounted by one of its ends The armature 17 acts by the

  end of a slide 18 on a fork of an arm 19 of the link 20 The link is mounted with possibility of oscillation on a support 21 of the mounting plate 15 and carries the stop head which is part of a first arm 22 When the electromagnet 16 exerts an attraction from the rest position, the rod 20 pivots

  to come to the stop position shown in dotted lines This sup-

  however, poses that the stop notch 10 and the stop head 12 are already in

  look at each other Otherwise, the stop head 12 applies

  that only against the peripheral surface 23 of the stop ring 9 under the action of a spring 24 which will be described later, until the stop notch 10 is brought to the place of the head d 'stop 12 The head

  stop 12 then falls into the notch 10 and prohibits the drive pulley

7 to continue its rotation.

  The rod 20 is held by the spring 24 in each

  of the two extreme positions (the rest position shown and the po-

  For this purpose, the spring 24 is tensioned between a hooking point 25 on the mounting plate 15 and a point

  lever 26 of the rod 20 so that, in both positions

  tions of the link 20, its line of action of forces 27 or 28 is located on different sides of the link bearing 29 The line of force 27 is located to the left of the link bearing 29 when the link 20 is in the rest position, while the line

  force action 28 is to the right of said bearing 29 when the biel-

  lette is in stop position (dotted line) The link 20 used

  eg two stable extreme pivot positions.

  The electromagnet 16 can be a pulse coil magnet

  simple, which receives a command impulse whenever the biel-

  lette 20 must be brought into its other extreme position The armature 17 sticks for a brief moment and moves the rod beyond the

  neutral point defined by spring 24 and the distance between the point of

  hooking 25 of the rod bearing spring 29 and then lets the rod tilt in the other position The arrangement of the electromagnet 16 in the form of an electromagnet with two coils is however safer, the voltage being applied to the coil 30 or 31 concerned (FIG. 3) depending on whether the rod 20 must be brought into the rest position or into the stop position. Pulses delivered by a device are used for this.

  of the washing machine not shown.

  Since it is useful to indicate to the communication device

  requests the prepared stop position of the link, i.e. the posi-

  tion in which the stop head 12 is applied to the surface 23 of

  the stop ring 9, far from the stop notch, an action micro-switch

  born by an arm of the link 20 can be provided, which micro-contact

  tor opens or closes a contact in the mentioned position of the link

  lette In the same way it can be useful to monitor the position

  link stop extreme 20 An indication of this type may

  initiate on the one hand a reduction in the speed of rotation of the laundry drum drive motor and on the other hand the complete stopping of the

drive motor.

  The invention is not only limited to the exemplary embodiment.

  sation shown For example, the armature 17 of the electromagnet with its slide 18 can act on the same side of the link bearing 29 as the stop head 12 This further reduces the overall height of the module 11 to take advantage of the travel space available for the laundry tub with all the accessories mounted on it In addition, one can use a spring instead of the tension spring 24

  of compression the lever point 26 on the link side would be located

  be the link bearing 29 and the attachment point 25 of the spring Ce

  compression spring can also be a branch spring.

  Advantageous arrangements of the invention consist in providing the stop head 12 as well as the surface 23 of the stop ring 9 with a wear resistant surface Simultaneously, the coefficient of

  friction of surface materials must be low so that the posi-

  prepared tion of the rod 20 for stopping, in which the stop head 12 slides on the surface 23 of the stop ring 9 which rotates,

  causes reduced wear In addition, the region at least of the

  stop bar 9 comprising the stop notch and / or the surface of the head

  stop 12 must have sufficient elasticity so that the jerk pro-

  reduced by the shock when the stop head 12 falls into the stop notch 10, therefore by the sudden stop of the drive pulley 7, that is to say as low

as possible.

  To further absorb the shock, the surface 23 of the crown

  stop 9 located just before the stop notch 10 in the direction of rotation

  tion can be arranged such that the surface of the stop head 12 forms with the stop ring a coefficient of friction as high as possible This allows to increase the braking action on the drive and reduce the rotational speed of it just

  before the engagement of the stop head 12 in the stop notch 10.

  Another form of limitation of the jerk due to stopping could be obtained by construction by establishing an elastic torsional connection between the stop ring and the drive of the drum or the laundry drum. This elastic connection can be provided either between the stop ring 9 and the drive pulley 7 or between the pulley

  drive 7 and coupling to the laundry drum 5 or the ac-

  coupling with the drive motor 2 (for example via

  drive belt 4).

  Contrary to what is shown in FIGS. 2 and 3, the first arm 22 carrying the stop head and the second arm 19 attacked by the frame 17 can be arranged on the side of the link bearing 29

  opposite the laundry tub 5 The first arm 22 then pivots from the outside

  laughing in the direction of the laundry tub 5 on an outer surface of the stop ring 9 facing the stop head 12, until the

  notch 10 arrives in the loading position The stop head 12 can

  then follows its movement towards the laundry tub 5 in the

stop 10.

Claims (8)

  1 Device for immobilizing in the loading position a washing drum for loading from above a washing machine, device   in which an electric motor drives a stop disc which is so-   lidaire in rotation of the laundry drum outside the laundry tub and whose outer profile has a stop notch which, in the laundry drum loading position, coincides with a movable stop head   linked to an electrically controlled drive device,   laughed at by the fact that the stop head (12) is part of a first arm (22) of a link (20) with two arms which has two extreme pivoting positions kept stable by means of a spring (24 ) and whose second arm (19) is connected to the armature (17) of an electromagnet (16)   which acts in the direction of pivoting or tangentially to it.   2 Device according to claim 1, characterized in that the armature (17) is hingedly connected to the second arm (19).   3 Device according to claim 1 or 2, characterized by the   causes the bistable behavior of the armature (17) of the electro-ai-   mant (16) is obtained by means of a spring (24) which is tensioned between a point (25) fixed relative to the electromagnet (16) and a lever point (26) of the link ( 20) located on the side of the link bearing (29) opposite the fixed point so that, in the two extreme positions of the link (20), the line of action (27, 28) of the spring force is   located on different sides of the link bearing (29).   4 Device according to claim 3, characterized in that, in the two extreme positions of the rod (20), the frame (17) is located in an extreme position relative to the excitation position. Device according to claim 3, characterized in that   that the electromagnet (16) has two coils (30, 31) whose zo-   nes of action correspond to the extreme positions of the armature.   6 Device according to any one of the pre- claims   cédentes, characterized by the fact that the catch (10) is arranged in elastic material.   7 Device according to any one of the pre- claims   , characterized in that the contour of the stop disc (cou-   stop bar 9) has a wear-resistant surface (23) ensuring sliding and the stop head (12) is made of a material producing a low   coefficient with the peripheral surface.   8 Device according to any one of the pre- claims   cédentes, characterized in that, in a zone of the stop disc (9) situated before the notch (10) in the direction of rotation of said disc,   the peripheral surface (23) of the disc produces a coefficient of friction   high with the stop head (12).   9 Device according to any one of the pre- claims   cédentes, characterized by the fact that the stop disc (9) is linked   elastic in torsion with the drum drive (2) or the washing drum (5).