Method of monitoring the filling of a washing machine drum with water

Abstract

A method of monitoring a washing machine aggregate for impermissible or atypical movements during a first phase of a washing program while water is being filled into the aggregate and for discontinuing the filling upon detection of such movement as may result, for instance, from the presence of a child or animal in the aggregate.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention, in general, relates to a method of monitoring the filling of a washing machine drum with water and, more particularly, to a method of the kind referred to in a washing machine provided with a housing, a washing aggregate including a tub mounted for oscillatory movement within the housing and including a drum rotatably mounted therein for receiving laundry and/or washing fluid and sensor for detecting a movement of the aggregate and for discontinuing any washing program upon recognition of an impermissible movement during a first phase of the washing program, with the drum being either stationary or rotating to and fro during the first phase.

2. The Prior Art

Such a method is generally known from the disclosure of Patent Abstracts of Japan No. JP 2004065408 A. It is provided with a sensor for detecting an impermissible movement of the drum or of the washing fluid tub during an idle time between initiation and execution of the washing program. A similar method has been disclosed by Patent Abstracts of Japan No. JP 10179978 A. A motion sensor or acceleration sensor mounted at an upper portion of the tub recognizes a detected movement as originating from a child within the drum. Its proper function is, however, dependent upon movements of the child.

Yet another method has been disclosed by German Laid-open Patent Specification No. DE 42 25 769 A1. In this case, weight present within the drum is detected by a weight sensor prior to initiation of a washing program and if the weight exceeds a predetermined threshold value the washing program is either not initiated or an alarm is activated. The method is suitable only for washing loads of no more than 4.5 or 5 kg of dry laundry, however. The method is unsuitable for larger washing machines with capacities of 8 kg of dry laundry because it cannot distinguish whether the detected weight originates with the permissible laundry in the drum or with a child of substantially the same weight.

OBJECT OF THE INVENTION

It is an object of the invention with simple means to improve the safety of, and thus protect from possible harm, a child present in the drum, accidentally or otherwise.

SUMMARY OF THE INVENTION

In the accomplishment of these and other objects, the invention provides a method of monitoring the filling of a washing machine drum with water and, more particularly, to a method of the kind referred to in a washing machine provided with a housing, a washing aggregate including a tub mounted for oscillatory movement within the housing and including a drum rotatably mounted therein for receiving laundry and/or washing fluid and sensor for detecting a movement of the aggregate and for discontinuing any washing program upon recognition of an impermissible movement during a first phase of the washing program, with the drum being either stationary or rotating to and fro during the first phase, the method including the step of introducing a predetermined quantity of water into the tub during the first phase of the washing program.

Further features of the novel program will become apparent as the description of the invention unfolds hereafter.

The advantage derived from the method in accordance with the invention is that a very reliable recognition of a child or pet within the drum of a washing machine results in high safety and the prevention of possible hazards and injuries. A further advantage is that the method is extremely simple and cost-efficient, since it depends upon the utilization of sensors and/or detectors for the weight of laundry or out of round movement of the drum which are standard features of current washing machines. The method is advantageously characterized the fact that a child sleeping in the drum will be woken and stimulated to move. This is accomplished in a simple manner by water, in particular cold water being introduced into the tub and drum after initiation of a washing program, i.e. after actuating a start button. A child resting or sleeping in the drum will thus be woken by the entering water and startled such that because of the unpleasant wet feeling it will move. Since during this first phase the drum is not yet moved by its drive, any detected movement will result in termination of a selected washing program. In a practical embodiment, the first phase of the washing program may include movements of the drum, especially rocking motions, in order effectively to induce any child in the drum to move. There are no possibilities of the child being hurt or injured by such movements.

After recognition of a child because of a movement of the drum in its idle phase, a visible or audible alarm may be issued or the loading door may be automatically unlatched and opened.

The quantity and temperature of the water are limited so that any child in the drum can neither drown nor be injured in any other way. To this end, the quantify of introduced water is only a partial portion of the washing liquid required for executing a washing program.,

Persons skilled in the art will understand that during the first phase of a washing program no detergents or other laundry agents are admitted to the tub and the drum. Thus, in an advantageous embodiment of the invention no laundry detergent or other substance is added to the water during an initial phase of the washing program. The water is caused to circumvent the detergent compartment of the washing machine during its initial feeding into the tub.

The duration of the first phase of the washing program is such that at the beginning of the first phase water is fed in, e.g., for about 30 seconds and that the machine remains idle thereafter, for instance for about 60 seconds prior to commencement of the second phase which includes the washing program proper. During the entire first phase, i.e. for about 90 seconds, the any movement of the washing aggregate or of drum will be monitored and upon detection of any movement caused by a child the second phase of the washing program will not be commenced.

Alternatively, the first phase may be terminated or interrupted immediately upon detection of impermissible movements in order to shorten the first phase and any time a child may be in the tub or drum and thus to reduce or prevent any traumatic experience.

Since the movement of the washing aggregate or of the drum caused by the water flowing in is clearly different from a movement caused by a child, faulty interpretations are avoided.

In a useful embodiment of the invention, a path sensor is used for detecting the movement. Such sensors are customarily provided between the washing aggregate and the housing. However, the detection may also be brought about by other means, such as, for example, tachometers, motion sensors, acceleration meters, pressure gages, power sensors or torsion sensors.

Advantageously, the detection or recognition of a child being impermissibly present in the drum and subject to harm therein, is fed to an evaluation unit.

The method is not limited in its application to the recognition of a child or animal being present in the drum of a washing machine, but it may be utilized to equal advantage to the detection of dogs, cats, rabbits birds or anything else which causes a washing machine drum to move impermissibly at a time when it should be stationary.

DETAILED DESCRIPTION OF THE SEVERAL DRAWINGS

The novel features which are considered to be characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, in respect of its structure, construction and lay-out as well as its manufacturing techniques, together with other advantages and objects thereof, will be best understood from the following description of preferred embodiments when read in connection with the appended drawings, in which:

FIG. 1 is a schematic presentation of the arrangement of a washing aggregate within a housing;

FIG. 2 exemplarily depicts a diagram of the condition of a washing program in a normal situation; and

FIG. 3 exemplarily depicts a diagram of the condition of a washing program in a faulty situation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS.

As schematically shown in FIG. 1, the washing aggregate or washing fluid tub 2 is suspended by springs 3 for oscillatory movements within the housing 1 of a washing machine housing from housing components not shown. The washing aggregate consists of a washing fluid tub 2 and a drum 16 mounted for rotary movement within the tub 2. Rotary movement is at times imparted to the drum 16 by a motor 19 by way of a belt drive. Shock absorbers 4 are provided to prevent excessive oscillations in case of imbalanced loads in the drum 16. A path sensor 6 detects not only any imbalance or the condition of a load within the drum 16 but also movements of the washing aggregate 2 or of the drum 16. An evaluation unit 5 is connected by way of a connecting line 7 to the path sensor 6 to receive from it any detected values. A detergent chamber 15 is provided to receive and during a washing operation to dispense predetermined amounts of detergent and/or other washing agents. A loading opening 17 is closed after loading the laundry into the drum 16 and before starting a selected washing program.

FIG. 2 schematically depicts the chronological sequence of a washing program. During an idle phase 8, the washing machine is either switched off or the user has nor yet started the washing program. At time t=5 the start button 9 is actuated which activates the first phase 10 of the washing program. During the first phase, means such as the path sensor 6 and an evaluation circuit 5 are activated for detecting any movement of the washing aggregate or of the drum 16. In addition, water, more particularly cold water, is fed to the washing fluid tub and into the drum 16 at the beginning of the first phase. The time during which water is fed and the quantity of the water are measured such that while a child or pet possibly present in the drum 16 will be drenched and woken and startled to move, it will not drown or undercooled. If no impermissible movement of the washing aggregate or of the drum 16 is detected during the first phase, the second phase 12 will succeed the first phase 10 at time t=8. The second phase includes the actual washing program selected by the user. The second phase 12 and the washing program which includes washing, rinsing and spinning cycles with strong drum movements will run completely until its programmed termination 13.

FIG. 3 by way of example depicts the chronological sequence of a program abortion 14. In this case, movement of the washing aggregate 2 was detected during the first phase 10 which led to premature termination 14 of the program at time t=8. However, it would also be possible at time t=7, immediately upon detection of an impermissible movement, prematurely to abort 14a and terminate the first phase 10. Upon recognition of an impermissible movement and following program abortion 14, 14a, an audible or visible alarm 18 may be issued and/or the loading opening 17 may be automatically unlatched or opened.

Claims

1. A method of operating a washing machine comprising a housing, a: washing aggregate suspended therein for oscillating movements, a washing drum mounted for motor-induced rotational movement within the aggregate for receiving laundry and washing fluid and means responsive to movement of the washing aggregate during a first phase of the washing program while the drum is in an idle state and cooperating with an evaluation circuit for discontinuing a washing program upon recognition of an impermissible movement of the aggregate by the evaluation circuit, comprising the step of filling a predetermined quantity of water into the tub during the first phase of the washing program.

2. The method of claim 1, wherein the predetermined quantity of water corresponds to a partial portion of the washing fluid.

3. The method of claim 2, wherein the washing machine further comprises a detergent dispensing chamber, further including the step of circumventing the detergent dispensing chamber when introducing the predetermined quantity of water.

4. The method of claim 1, wherein the movement of the aggregate during the first phase is detected bay a path sensor.

5. The method of claim 1, wherein movement of the washing aggregate is detected by a sensor responsive to at least one of number of rotations, movement, acceleration, pressure, force and torsion.

6. The method of claim 1, further including the step of immediately upon recognizing an impermissible movement of the aggregate the first phase is prematurely discontinued.

7. The method of claim 6, further including the step of automatically unlatching the loading opening upon recognizing an impermissible movement of the aggregate.

8. The method of claim 6, further including the step of automatically opening the loading opening upon recognizing an impermissible movement of the aggregate.

9. The method of claim 1, further including the step of issuing an alarm upon recognizing an impermissible movement of the aggregate.

10. The method of claim 9, wherein the alarm is an audible one.

11. The method of claim 9, wherein the alarm is a visible one.