NL194336C - Automatically controlled washing machine. - Google Patents

Description

> 1 194336

Automatically controlled laundry handling macniria

The invention relates to an automatically controlled washing machine for household use which is provided with a washing drum with a loading aperture and with a member registering the weight of the loaded washing drum 5, which is connected to a signal processing circuit which is connected to a signal for operation gives a signal from the washing machine too high a weight.

Such a washing treatment machine is known from the European patent application 0.051.491. In this washing machine, a sound or visual warning signal is generated when the weight-sensing device detects a weight that is too high. The object of the invention is to make the use of washing machines safer, in the sense that it is prevented that a washing machine can be started when, for example, a small child or a pet has crawled into the washing bin. This starting could, for example, be performed by another child while playing.

To this end the invention provides a washing machine of the above-mentioned type, wherein the signal is a blocking signal for preventing the start of a washing treatment program.

It is noted that a combined washing and drying machine is known from British patent application 2,247,250 which cannot be started if the amount of washing in the machine is too high to be dried. This only concerns a block to prevent the sub-optimal functioning of the machine and no protection against starting the machine when, for example, a child is present in the drum thereof.

The threshold value for the loading weight, at which the blocking signal must already be issued, can be a fixed predetermined value or be variable.

In a preferred embodiment of the invention, the machine control has a voltage comparator with a memory for a plurality of loading weight thresholds, which can be called up according to the state of the program and can be fed to the voltage comparator together with the observed value of the loading weight. For example, the likely loading weight of a washing machine before starting the wash treatment program is equal to or less than 4.5 kg. The threshold value can therefore be set at 4.5 kg. Moreover, this measure has the advantage that a washing program cannot be started if the drum is overloaded. An optical signal on the control panel can also be useful for this purpose.

In further program components, the load weight of the drum can be considerably higher as a result of the water absorption by the wax, so that the threshold value in this case must be correspondingly higher. This can also be important in the case of a combined washing and drying machine, whereby a washing load of only 3.5 kg of dry washing is permissible for the drying program following the washing program.

With a tumble dryer, the threshold value may be set to, for example, 8 kg, corresponding to a loading weight of 4.5 kg of dry wax excluding the moisture contained in the wash after a spin treatment through a previous wash and spin program. In the case of a tumble dryer, the threshold value can be set such that a certain amount of wax with a too large proportion of water bound to the fabric cannot be dried automatically so that not too much thermal energy is lost. Such a quantity of wax must first be centrifuged as dry as possible, so that only a minimum amount of thermal energy is required to expel the remaining moisture. As a result, a dripping wet amount of washing can be excluded from drying in the tumble dryer.

45

The invention will be elucidated on the basis of an exemplary embodiment with reference to the drawing, in which Figure 1 shows a vertical section through a dryer according to the invention along the center axis of the drum and Figure 2 shows a block diagram of a signal processing circuit for preventing the start of a drying program

The washing drum 1 according to Figure 1 carries on its rear wall 2, which is perforated in the middle section, a bearing pin 3 which is rotatably mounted in a drum bearing 4. In addition, in the region of the loading opening 6, the washing drum has a flange 27 for a further bearing, the front drum bearing 7. The drum bearing 7 comprises a sealing gasket 9 mounted on a frame portion 12 of the loading opening 6, in which sliding pieces are mounted. The seal 9 may consist of felt strips and prevent the

Claims (2)

194336 2 drum space entered air escaped under pressure through the gap of the bearing. Instead, the air steams through the perforated, wax-retaining, part 10 placed in the loading opening to a tube not shown here, which carries the air under pressure to the drum space to be reheated by the heater 11. Similar rear sealing rings 13 seal the drum 1 at the air supply pipe 14 opposite the environment. A measuring sensor 8 responsive to pressure or movement is additionally placed on the front drum bearing 7, which sensor gives a signal upon pressure or movement of objects loaded in the washing drum 1. The washing drum pivots downwards at a minimal angle. Instead of a weight processing sensor 8 arranged in the front drum bearing 7, a weight sensor can be arranged in a corresponding manner on the rear drum bearing 4, which for example reports voltages which arise in the bearing 4 or on the rear wall 15 of the washing drum. Moreover, the bearing can also be arranged vertically movable between springs, the displacement of the bearing being a measure of the weight of the load. In the diagrammatically shown circuit according to figure 2, signals relating to the loading weight of the drum can be processed. The measuring sensor 8 outputs its weight signals to a voltage comparator 16, which compares these signals with a threshold located at its other input, which is supplied by a generator for threshold value signals 17. As soon as the weight signals from the measuring sensor 8 register a larger load, the negative changes. output signal of the voltage comparator 16 in a positive signal. This positive signal is changed at the inverted input of the AND element 18 into a blocking signal at its output, which blocking signal is fed to a program switching device 19. Normally, that is, with a normal loading of the washing drum, the output of the voltage comparator 16 has a negative potential, which is converted into a positive signal by the inversion at the relevant input of the AND element 18. Only if the other input of the AND element 8 also receives a positive signal from the tumble dryer when the start switch 20 is switched on, does the output of the AND element 18 carry a start signal for the program switching device 19. This ensures that the washing treatment machine, in this case a tumble dryer, cannot be put into operation if the load of the washing drum has a weight that is above normal proportions; The threshold signal generator 17 may comprise a memory for several different threshold values 30, which memory can be read out via a signal from the program switch device 19 depending on the program component. Then different threshold values for the amount of charge can be applied in advance to the voltage comparator 16, so that always different maximum charges can be taken into account. 35 What is claimed is: 1. An automatically controlled domestic washing machine comprising a washing drum with a loading aperture and a member registering the weight of the loaded washing drum connected to a signal processing circuit which is too high for registering a washing machine to operate emits a signal, characterized in that the signal is a blocking signal for preventing the start of a washing treatment program. Automatically controlled washing machine according to claim 1, characterized in that the machine control comprises a voltage comparator (16) with a memory for a plurality of threshold values (17) of load weights 45, which can be called up depending on the program item and together with the recorded value from the load weight to the voltage comparator (16). Hereby 1 sheet drawing