US3696903A

US3696903A - Washing or other machines

Info

Publication number: US3696903A
Application number: US81407A
Authority: US
Inventors: Barry Herbert Nethersell
Original assignee: British Domestic Appliances Ltd
Current assignee: British Domestic Appliances Ltd
Priority date: 1969-10-20
Filing date: 1970-10-16
Publication date: 1972-10-10
Anticipated expiration: 1989-10-10
Also published as: GB1310680A; NO128664B; ZA707071B; CA928095A

Abstract

A spin dryer for clothes, or an upright clothes washing machine in which the clothes drum rotates to dry clothes is provided with a lid which is locked at all times when the drum is rotating, the lock mechanism being actuated by bob-weights which are thrown outwards when a drive motor for the drum is rotating. The mechanism also includes an interlock which prevents the motor being energized unless the lid is closed and a control lever is correctly set.

Description

United States Patent Nethersell Oct. 10, 1972 [54] WASHING OR OTHER MACHINES 1,162,847 12/1915 Binder ..l92/136 1,236,529 8/1917 Balzer ..l92/136 [72] Herbert Deganwy 1,531,844 3/1925 Colclough ..192/136 1,989,213 1/1935 Schenck ..192/136 [73] Assignee: British Domestic Appliances Limited, Peterborough, E l d Primary Examiner-Allan D. Herrmann tt l Filed: Oct. 1970 A orney Larson Tay or&l'lmds [21] App]. No.: 81,407 ABSTRACT A spin dryer for clothes, or an upright clothes washing [30] Foreign Application Priority Data machine in which the clothes drum rotates to dry clothes is provided with a lid which is locked at all Oct. 20, Great Bl'ltalll times when the drum is rotating the lock mechanism being actuated by bob-weights which are thrown out- [52] US. Cl ..l92/136, 68/28 wards when a drive motor for the drum is rotating. [5]] Int. Cl. ..F 16d 67/00, D061 39/14 The mechanism also includes an interlock which [58] Field of Search....192/ 135, 136; 68/28; 210/146 prevents the motor being energized unless the lid is closed and a control lever is correctly set. [56] References Cited 8 Cl 5 Drawing figures UNITED STATES PATENTS 1,006,523 10/1911 Bartholomew...,....,,,.192/136 PATENTED 10 I972 3.696 903 sum 2 OF 3 T M AW}.

PATENTEDum 10 1912 3.696.903

SHEET 3 [IF 3 24 Moror16 34 Fig. 5

WASHING on OTHER MACHINES This invention relates to clothes washing or spin-drying machines in which clothes to be treated are placed in a rotatable drum driven by an electric motor, the drum being provided with an access opening.

Such machines are normally provided with a door hingedly connected to a housing of the machine and having a fastening device, which is arranged to cooperate with a safety latch arrangement so that the door cannot be opened until the drum stops following interruption or termination of the operation of the machine. It is also customary in machines of this type to provide a switch in the electric power supply to the motor such that the motor may not be energized whilst the door is opened.

Previous safety arrangements have variously comprised, for example, electro-magnetic braking devices for the drum associated with a switch actuated by the opening door which de-energizes the electric motor. Such arrangements have not been entirely successful in so far as it has been necessary, due to manufacturing tolerances and to wear which may occur in the various parts of the machine, to permit the door to be opened at least a small amount, before the various control switches are actuated. Such an opening may well be sufficient to permit the user or, more particularly, a child to insert a hand into the machine to contact the moving drum.

An object of the present invention is to provide a controlled washing or spin-drying machine which is safer in use.

According to the present invention a clothes washing or spin drying machine comprises a rotatable clothes drum driven by an electric motor and having an access opening which is'closed by an access door, a main switch associated both with the access door and with a manual control linkage in such a way that energization of the motor is effectable only when the access door is shut and the manual control linkage is set to a position corresponding to the operation of the machine, and a centrifugally operated mechanism which actuates a locking mechanism for the access door whereby the access door may not be opened whilst the motor is rotating at a speed above a predetermined value.

Preferably the machine includes clutch means interposed between the electric motor and the rotatable drum, the characteristics of the clutch means being such that the door locking mechanism is rendered operative by the centrifugally operated mechanism prior to the motor drive becoming fully effective at the drum.

The centrifugally operated mechanism may comprise one or more bob-weights secured to an output shaft of the motor at a distance from the axis of rotation of the shaft and so arranged as to move outwards from the axis of rotation of the shaft in response to increasing speed of rotation of the shaft, and sensing means responsive to a predetermined outward movement of the bob-weight or bob-weights to actuate the locking mechanism for the access door.

Preferably the machine includes brake means actuated in conjunction with the main switch so that the brake means is operative at all times that the electric motor is de-energized.

Conveniently, the electric motor is a split phase induction motor and the auxiliary windings of the motor are energized by way of an auxiliary switch arranged to be opened by the centrifugally operated mechanism when the speed of the motor has attained a predetermined value.

The main switch for the electric motor may be controlled by an arm which is movable with the access door and which, when the door is moving towards a closed position, engages with a lever to cause the lever to bias the main switch into a position in which it is operable by the arm on further closing movement of the door, the lever being so formed that it is permitted to return to an un-actuated position and thus return the main switch to its unbiased position and so prevent its operation by the arm as the door closes unless it is engaged and held by a latch, the latch having two alternative positions selectable by the manual control linkage, a first position, corresponding to operation of the machine, in which the latch is able to engage and hold the lever in its actuated position, thus permitting the arm to actuate the main switch, and a second position in which the lever is permitted to return to its unactuated position as the door closes thereby preventing actuation of the main switch. Conveniently the lever also actuates the brake means in such a way that when the lever is in its un-actuated position the brake is operative. Further, the latch may be arranged to move to its second position in the event that the door of the machine is opened whilst the manual control linkage is set to the operative position, thereby permitting the lever to return to its un-actuated position and so release the main switch to de-energize the motor.

In order that the invention may be more readily understood one embodiment will now be described by way of an example, with reference to the accompanying drawings in which;

FIG. 1 shows the essential internal details of a spin drying machine, the cabinet being omitted for clarity.

FIG. 2 is a fragmentary sectional view showing a centrifugally actuated switch door and lock operating mechanism;

FIG. 3 is a fragmentary sectional view showing the door lock itself.

FIG. 4 is a part sectional view of the control mechanism for the main switch.

FIG. 5 is a schematic circuit diagram of the control circuit.

Thus, with reference to FIG. 1, a spin drying machine comprises an outer liquid container I, mounted within a cabinet (not shown) and an inner perforate clothes drum 2 mounted for rotation about a generally vertical axis. The clothes drum 2 is supported by a drive shaft 3 which is held in a bearing arrangement 4 provided below the lower wall of the outer container 1 and resiliently supported in such a way as to permit the clothes drum to rotate in an eccentric manner within the outer container if affected by out of balance forces during operation. Egress of liquid from the container to the bearing arrangement is prevented by a rubber bellows 5 sealed to the container and provided with a carbon face-seal 6 which bears on a counterface provided on the clothes drum 2. A pipe (not shown) is connected to the lower wall of the liquid container and serves to remove any liquid collecting in the outer container during operation of the machine.

The drive shaft 3 is coupled to the driven member 7 of a centrifugally actuated friction clutch, which is provided with a friction band brake 9 actuated, via a sheathed wire cable 10, by a control mechanism 11 for both the brake and a main isolating switch 12 of the machine (see also FIG. 4). The driver member 8 of the clutch is coupled by means of a V-belt 13 to a pulley 14 carried by an output shaft 15 of an electric splitphase induction motor 16 which is supported within the cabinet by suspension means (not shown). The main isolating switch can be operated to connect the terminals L and N of a source of alternating current to a main winding 24 and an auxiliary winding 34 of the induction motor 16 (see FIG.

A centrifugally actuated switch and door lock operating mechanism (see also FIG. 2) is fitted to the shaft at the end of the motor 16 opposite to the output pulley 14. The mechanism comprises a pair of similar bob-weights 17 each of which is pivotally supported on the shaft 15 by means of a lower arm 18 connected by means of a pin-joint with a collar 19 mounted on the shaft and secured thereto by means of a locking screw 20, and an upper arm 21 connected in similar fashion to an upper collar 22 which is secured to a cylindrical plunger 23 surrounding the upper extremity of the shaft 15. A coil compression spring 25 is housed within the plunger 23 between the plunger and a recess 26 provided in the end surface of the shaft 15. On rotation of the shaft the bob weights tend to fly outwardly from the shaft and the plunger 23 is thereby urged downwards towards the collar 19 against the effort of the spring 25.

An extension 27 of the plunger 23 engages with a forked member provided at one end of a lever 28 which is pivotally mounted on a bracket 29 secured to the motor casing. Movement of the plunger 23 is thus transferred by the lever 28 to an inner cable of a sheathed wire cable 30 which is operatively connected at its opposite end toa door lock 31 which is shown in greater detail in FIG. 3. A plunger 32 of an isolating switch 33 for the auxiliary winding 34 of the motor 16 is arranged in the path of the movement of the lever 28. The above arrangement thus provides a sensing means responsive to a predetermined outward movement of the bob-weight to actuate the locking mechanism or the access door. The lever is also arranged to bear against a spring loaded conical plunger 35 so as to provide a snap action to the lever thereby to bias it firmly into one of two alternative positions as will be described hereinafter.

The door lock 31 (see in particular FIG. 3) comprises a lever arm 36 which is secured to a part of the cabinet of the machine by means of a bracket 37 through a slot in which the lever arm passes and is clamped by means of a leaf spring 38. The lever arm 36 is connected at one end to the inner cable of the sheathed wire cable 30 by means of a pinned stirrup 39 and is provided at its opposite end with a tongue 40 which serves, when the lock is actuated, to enter a hole provided in a part of the access door 41 of the spin drier and thereby lock the door shut. The tongue 40 passes through a part of the wall of the liquid container 1 which is sealed against the egress of liquid at this point by means of a lip seal 42. When actuated by the sheathed wire cable 30 the lever arm 36 pivots about a fulcrum point 49' to move the tongue 40 into engagement with the door 41 if, however, this movement is baulked, for instance, by the door not being properly closed so that the tongue may not enter the hole, the lever arm is able to move in the slotted portion of the bracket 37 thus obviating strain on the actuating linkage and permitting the motor auxiliary windings to be isolated at the correct time by operation of the switch 33 by the lever 28 thus ensuring protection of the auxiliary winding.

The control mechanism 11 see FIG. 4) for the brake 9 and the main isolating switch 12 for the machine comprises an arm 43 which is attached to a hinge pin 44 of the door 41 so as to pivot with the door, but perpendicular thereto. The arm 43 is provided at its end remote from the door with an L-shaped follower 45 which is arranged to engage the floor of a U-section lever 46 as the door approaches its closed position. The floor of the lever 46 is cut away towards one end so as to provide a hole 66 through which the arm 43 may pass, thus releasing the lever 46 to return to its inoperative position, if not otherwise latched, as will be described hereinafter, as the door 41 moves further towards the closed position. When the lever 46 is thus released the follower 45 is pushed to an inoperative position by the movement of the lever in order to obviate further contact between lever and the arm 43 on opening of the door. The follower 45 is able to return to its operative position under the influence of a return spring (not shown) only when the door 41 has been fully opened. The lever 46 is pivotally secured by means of a pin 47 to a plate 48 and is provided with a biassing arm 50 which is movable by the lever 46 against the effort of a counter-spring 51 as the lever moves downwards. A latch 52 for the lever 46 is pivotable on the plate 48 about a pins 53, one end of the latch being so formed as to be engageable with the lever 46 so as, when actuated, to prevent it returning to its inoperative position when released by the arm 43 and the opposite end co-operating with a cam 54 on the door in such a way that the latch 52 is held disengaged from the lever 46 while the door is open. The latch 52 may also be operated by a switch arm 55, radial movement of which between its ON and OFF positions is translated into longitudinal movement of a coupling rod 56 by engagement of the switch arm with either of two

nuts

57 or 58 on the rod. Movement of the latch 52 by the rod is effected by either of two further nuts 59 and 60 on the rod 56, the nut 60, corresponding to the ON position of the switch arm 55, actuating the latch into its operative position via a coil compression spring 61 so that, notwithstanding the switch arm being in its ON position, the cam 54 may move the latch 52 to its inoperative position in the event of the door being opened.

Considering now a typical sequence of operations for spin drying. The door 41 is opened, the articles to be dried are inserted and the switch arm 55 is moved to its ON position, thus biassing the latch 52 upon its operative position against the action of the cam 54. Upon closing the door the arm 43 moves the free end of the lever 46 downwards releasing the brake 9 via the cable 10 and moving the main isolating switch 12 into its operable position. As the door closes the cam 54 releases the latch 52 to move into its operative position, the brake 9 being released and the main isolating switch 12 being held in its position so that the follower 45 attached to the arm 43 is able to engage the plunger 62 of the switch and energize the electric motor 16.

As the electric motor accelerates to running speed the bob-weights 17 (FIGS. 1 and 2) fly outwards to move the lever 28 over center and thereby open the switch 33 and de-energize the auxiliary windings of the motor and also move the tongue 40 (See FIG. 3) of the door lock into engagement with the door, preventing it from being opened during the remainder of the operation. The clutch driven member 7 and the clothes drum 2 are now accelerated to the speed of the clutch driving member 8 and the drum rotates at full speed for as long as is desired, or until a predetermined time, selected by a programme timer (not shown) has elapsed.

To stop the drying operation the switch arm 55 is moved to its OFF position thereby moving the latch 52 to release the lever 46 causing the brake to be applied and the switch 12 to move to its inoperable position thereby de-energizing the electric motor 16 with the result that the clothes drum 2 comes rapidly to rest. As the motor comes to rest the bob weights 17 return to their rest position and release the door lock 31 so that the door may be opened and the dried clothes removed from the clothes drum.

It will be appreciated that the present invention provides a far safer construction of clothes washing or spin-drying machine of the type described, in particular;

with the door of the machine closed it is not possible to switch the machine on by manipulation of the switch arm; the door must be opened and the switch arm subsequently set to ON before closing the door to start the machine. Such an arrangement is particularly desirable in that it makes it extremely difficult for a child to start the machine in operation;

if the door lock is prevented from operating in some way, and if the door is opened the brake will be applied and the motor will be de-energized immediately, in the latter event before the clothes drum has started to rotate;

in the event of a power failure the door will remain locked until the motor speed and hence the drum speed, has fallen sufficiently to release the door lock, and, even if the door is opened immediately the door lock has been released the brake will be applied to stop the drum very rapidly.

It will also be appreciated that, whilst the particular embodiment described has been a spin-drying machine, the invention is applicable to a wide range of clothestreatment machines of a generally similar type.

I claim:

1. A clothes washing or spin drying machine comprising:

a. a rotatable clothes drum having an access opening;

b. an access door arranged to close the access openc. an electric motor means for rotating the clothes drum;

d. a main switch means associated both with the access door and with a manual control linkage for energizing the motor only when the access door is shut and the manual control linkage is set to a position corresponding to operation of the machine;

e. hentrifugally operated means for actuating a locking mechanism for the access door to prevent opening of the access door while the motor is rotating at a speed above a predetermined value.

2. A machine as claimed in claim 1, including clutch means operatively interposed between the electric motor means and the rotatable drum for rendering the door locking mechanism operative by the centrifugally operated means prior to the drive of said motor means becoming fully effective at the drum.

3. A machine as claimed in claim 1, wherein the centrifugally operated means comprises at least one bobweight secured to an output shaft of the motor means at a distance from the axis of rotation of the shaft and movable outwardly from the axis of rotation of the shaft in response to increasing speed of rotation of the shaft, and sensing means responsive to a predetermined outward movement of the bob-weight or bob-weights to actuate the locking mechanism for the access door.

4. A machine as claimed in claim 1, including brake means actuated in conjunction with said main switch means so that the brake means is operative at all times that the electric motor means is de-energized.

5. A machine as claimed in claim 1, wherein the electric motor means is a split phase induction motor and including an auxiliary switch means openable by the centrifugally operated means when the speed of the motor has attained a predetermined value to energizing the auxiliary windings of the motor.

6. A machine as claimed in claim 1, an arm movable with the access door, said arm engaging a lever when the door is moving towards a closed position to cause the lever to bias said main switch means into a position in which it is operable by the arm on a further closing movement of the door, the lever being so formed that it is permitted to return to an actuated position and thus return the main switch to its unbiased position and so prevent its operation by the arm as the door closes unless it is engaged and held by a latch, the latch having two alternative positions selectable by the manual control linkage, a first position, corresponding to operation of the machine, in which the latch is able to engage and hold the lever in its actuated position, thus permitting the arm to actuate said main switch means, and a second position in which the lever is permitted to return to its unactuated position as the door closes, thereby preventing actuation of the main switch.

7. A machine as claimed in claim 6, wherein the lever is positioned to also actuate the brake means in such a way that when the lever is in its un-actuated position the brake means is operative.

8. A machine as claimed in claim 6, wherein the latch is arranged to move to its second position if the access door is opened whilst the manual control linkage is set to the operative position, thereby permitting the lever to return to its un-actuated position and so release the main switch means to de-energize the motor.

Claims

1. A clothes washing or spin drying machine comprising: a. a rotatable clothes drum having an access opening; b. an access door arranged to close the access opening; c. an electric motor means for rotating the clothes drum; d. a main switch means associated both with the access door and with a manual control linkage for energizing the motor only when the access door is shut and the manual control linkage is set to a position corresponding to operation of the machine; and e. a centrifugally operated means for actuating a locking mechanism for the access door to prevent opening of the access door while the motor is rotating at a speed above a predetermined value.

3. A machine as claimed in claim 1, wherein the centrifugally operated means comprises at least one bob-weight secured to an output shaft of the motor means at a distance from the axis of rotation of the shaft and movable outwardly from the axis of rotation of the shaft in response to increasing speed of rotation of the shaft, and sensing means responsive to a predetermined outward movement of the bob-weight or bob-weights to actuate the locking mechanism for the access door.