DE2024591A1 - Process for washing and drying textiles and a combined washing and spinning machine for carrying out this process - Google Patents

Description

PHN.

Wij / VJM.

I '" ¹ · - · ¹ · ΚΪ.ΡΪ-T.RUANN

Vi. I. i'l.l'.V.'tit

Akfe No. PHN-4408
Registration dated: I5, Hal 1970

Method for washing and drying textiles and a combined washing and spinning machine to carry out this procedure.

The invention relates to a method

for washing and drying textiles in a combined washing machine and spinning machine that has an elastic suspension or supported tub with inside a drum rotatable about a horizontal or almost horizontal axis, a drive device, that of an electric motor for driving the drum at a washing and a spin speed exists, a supply for this motor and transmission elements with a constant transmission ratio between the motor and the drum shaft and means for supplying and removing water. «

009848 / 1'34 0.

The invention also relates to a

combined washing and spinning machine to carry out this process.

In a known washing machine, the

Washing and spinning speeds either directly by a two-speed motor, or indirectly through a motor and a gear set | box with several transmission ratios, or obtained by a pole-changing motor, with the change in the Rotation speed is obtained by commutation of the poles.

Numerous studies carried out in the field of spinning have shown that it is necessary, at least in certain cases, that the washing drum rotates at a relatively high speed, in the order of magnitude of 1000 rpm, so that only the smallest possible amount of residual water in the fibers the treated laundry remains.
™ Pedal at these great speeds

in particular, disturbing vibration phenomena caused by poor distribution of the laundry Are due to a lack of equilibrium. Numerous solutions have been proposed, the most famous of which are Balancing devices with moving masses, placing the drum on shock absorbers, making the drum more difficult, etc. are. All these aids, which mean an improvement that should not be underestimated by reducing the The amplitude of the vibrations, however, is too much of the charge

009848/1340

202 A 591

PHN.

depending on the machine * In addition, vibrations occur with very large amplitude due to the resonance at a certain speed; this speed, which is referred to as the critical speed, must be very can be exceeded quickly, otherwise the machine can be damaged.

Certain methods of distributing the laundry to be treated in the drum lead to a reduction in the Vibrations. During the spinning process, for example, when the amplitude of the vibrations is too high The engine is switched off by electrical devices, which devices subsequently turn the engine off during a Turn for a short time, after which the spinning starts again.

It has also been found that immediately after the rinse, when the tub is still full of water, it is possible to ensure a good distribution of the laundry in the A

Drum when this in a short time to a rotational speed in the order of magnitude of 70 to 100 rpm is brought.

During this so-called "distribution period", the laundry to be treated is more or less distributed evenly over the circumference of the drum, so that when emptying of the vat before the start of the spinning process low acceleration is sufficient to counteract the laundry To press drum wall. In this way a relative equilibrium is obtained that is still sufficient when spinning

OCFC ■ Ρ'- 1 3 £ 0 ■ ■

bath

PHN.

takes place at a speed that is not too high, in the order of magnitude of ^ QO to 600 rpm.

In general, the speed is on

Spin speed brought when the vat is empty, but also when one, thanks to the distribution that is on a balance This avoids vibrations that can be traced back to a lack of vibrations, and at least the critical speed is exceeded Resonance phenomena which, depending on the length of time in which they arise, can cause major disadvantages.

To avoid this critical point it is

possible to increase the speed and thereafter to empty the _f bot tich. Theoretically there is nothing against it, but in practice it is necessary that the motor power is relatively high in order to overcome the moment of resistance that is due to the friction of the water, while the centrifugal force generated by the amount of water carried along at the centrifugal speed is one exerts considerable pressure on the heat of the vat, making it necessary to use a very strong construction.

A machine in which the distribution methods are used usually has a second motor with an adapted one Speed or a multi-pole motor, its speed can be changed by pole changing, or mechanical means. After the wash and rinse cycle can then proceed according to two methods, whereby the vat is filled with water:

- you leave the drum on for a certain time

'0 0 98 4 8/1340

BATH ORIGINAL

PHN. 44θ8.

turn the dispensing speed, after which the vat is emptied the switch to spin speed only takes place when the water level is low enough,

- you let the drum rotate at the distribution speed and start emptying the at the same time Vats on; the spin speed is only switched on when the water level is low enough. j

You should note that the balancing is done

Distribution can only be carried out approximately correctly; it is always necessary to have the traditional devices that can be used to reduce vibrations, such as springs, shock absorbers and inertial masses. The results are sufficient if the spin speeds are relatively low, in the order of 400 to 600 rpm. % At higher speeds in the order of 1000 rev / min must take into account the balance problem, because the slightest lack of balance that remains in the distribution speed is then very important. The balance achieved at low speeds then no longer corresponds to that required to maintain equilibrium at high speeds, while the time required to restore the balance is long enough to cause movements of great amplitude. It is necessary to switch to a previous balancing at a speed that is not too low »which is significantly higher than ■ v .009848 / 1340

PHN.

Distribution speed. For a speed of 1OOO rev / Namely, it is desirable to achieve balance at speeds of about 200 rpm or higher. It it is then advantageous to use known devices, for example a device with which opposite the point, where there is an imbalance, a certain amount of water is brought into diametrically fixed chambers connected to the drum.

In the known prior art, this balancing speed just by using either a speed variator between the motor and the drum or a multi-pole motor with commutation of the number of poles.

The invention aims to provide a method and an apparatus which solve the following Give problems:

the problem of maintaining a spreading speed and a balancing speed without using an additional device for speed change or a motor, which besides those to maintain the low and the high speed windings required Winding contains to maintain each of the other speeds,

- the problem of exceeding the critical

Speed in the acceleration period under such Conditions that normally occur during this phase Vibrations remain limited

The process according to the invention is now through

009848/1340

PHN.

marked that after the wash cycle when the engine switched to spin speed and the drum accelerates while the vat is still filled with water, an intermediate speed is reached at which a Balance between the torque delivered to the drum shaft and the moment of reaction of the same, which equilibrium is maintained until the water in the tub in Rotary motion and the reaction torque of the drum q has become smaller, after which the acceleration of the drum continues.

Fig. 1 shows an example of the way

as, according to the invention, the drum speed as a function the time can be changed.

When the vat is filled with water, the critical speed is in the vicinity of 100 rpm. the Distribution speed, in the order of 70 rpm, is therefore smaller than this speed and that of the distribution required tent can be chosen ο line trouble · That The engine torque is predetermined in such a way that when the engine is exposed to the electrical parameters, the spin speed as well as a limited one Torque, this motor starts up very quickly and reaches the distribution speed that is required for the motor has not dragged along the entire mass in the machine's vat, remains approximately constant. This mass will through the drum, the laundry to be treated and the water formed in the vat. The torque generated by the engine

0098 1 8/1340

PHN. 4408.

then speaks to the reaction torque of this entire mass during a period of time which is determined by the engine power.

If the vat contains water «the drum speed will only increase up to a certain value, wherein the motor torque corresponds to the reaction torque caused by the friction of the water moving between the walls of the drum and the tub. If the water level in the tub is kept constant, this speed will remain constant. The partial or full Removal of the water reduces the moment of resistance and. Enables a new constant speed or the To reach spin speed.

The moment of resistance caused by the friction of the water between the walls of the tub and the drum and the fact that the entire mass in the tub is made to rotate is determined by the characteristics of the washing machine.

These distinctive properties are both electrical as well as mechanical type.

Dip electrical characteristics

mainly by the engine and its feeder while I the mechanical characteristic properties, including the mechanical characteristic properties of the engine and its gearbox, the dimensions of the tank and the drum, the volume and the water content of the vat, the inner and outer profiles of the drum " and the distance between the drum wall and the tub wall. IK -.'- .. ·. J fc U

BATH ORIGINAL

PHN.

The influence of each of these parameters is more or less important: the internal profile of the drum is, for example play an important role when the drum starts up; Adjusted ribs are dragging along the laundry and the mass of water, while the distance between the walls of the drum and the tub is a determining factor Will exert an influence on the size of the torque.

After the spin cycle, the drum is braked by mechanical or electrical means, which are very effective ensure rapid standstill of the drum, so that during the decrease in speed the critical to exceeding Speed required time will be as small as possible and thus oscillations too large amplitude the time do not get to develop.

When accelerating, it is known to exceed the critical speed of the drum with a vat filled with water. The inertial mass of these embassies% TLCH so hatι limits the resonant vibrations, while at the same time the tub needs to be less difficult by conventional means. It has therefore been proposed to start emptying the vat only after the critical speed has been exceeded. However, there is not just one critical speed; as a rule, the critical speeds are different in the three mutually perpendicular directions of movement of the drum.

These speeds are between 100 and 160 rpm. The most annoying critical speed is dle-

009848/1340

those in which the drum is exposed to movements stand vertically on their axis in the horizontal direction, and the speed is 100 rpm, among other things. That speed changes proportionally as the vat is emptied wony.

The time required to exceed the critical speed must be as short as possible So it is necessary that the acceleration of the drum is relatively high in this area. «The electrical parameters of the motor must be such »that the distribution tent is relatively long, in the order of magnitude of a few seconds, what is the time required for a few revolutions of the drum; after that there must be a strong acceleration in the range of critical speeds between 100 and 160 rpm take place.

When this speed range is passed, the drum reaches a constant speed while during which the balancing takes place, for example by the fact that some are firmly connected to the drum Chambers are filled with a certain amount of water. Devices for this are known. For great accuracy it is advantageous to do this at a sufficiently high speed, but it must not be done at a such high speed take place that the centrifugal force exerted on the vat by the water moraine is too grows large; a speed in the order of magnitude of 200 to 300 U / «in let * rvün« cht.

009348/1 3AQ

'ORIGINAL INSPECTED

PHN.

- 11 -

An embodiment of the invention is shown in the drawing and is described in more detail below. It «own:

1 shows a diagram relating to the mode of operation of a machine according to the invention,

2 shows a schematic section through a machine according to the invention.

2 shows the tub 1, which has a diameter of 50 cm and an internal volume of 30 liters, and which is suspended by means of springs 2 and supported by shock absorbers 3. The drum k in the tub 1 has three ribs 5 'which are advantageous over the circumference, and the diameter of the drum is about ' -4 (y cm.

In the bottom of the tub there are the heating plomontp <> and üor resistance 7

A motor 8 attached to the tub ensures the threat of the drum via gill plates, the transmission ratio of which is 1 (> * A pump driven by a motor takes care of the removal of the water and has an output of 30 1 min.

The machine control panel contains one

Button of the program selector, a switch to turn off the Machine, a potentiometer for toahl the Schleudergeschvindi ^ - or to end the spinning process. The program selector is fulfilled the tasks normally assigned to him, i.e. regulating the cycles, regulating the water level according to the treatment to be carried out, the functioning

, 0 C 9 8 '-. · 1 2 1 0

PHN.

- 12 -

of the washing and spinning motor, etc.

The motor 8 that drives the drum is a

AC motor with two windings: one of these windings is used for wash speed while the other is used for spin speed. One An electronic arrangement of the known type supplies the winding used for the spin speed with an electric current, the parameters of which are the spin speed, if the tub does not contain water, as well as the distribution speed in the order of 70 rpm, if the Vat is filled with water. The discharge of the Water starts only after the distribution speed has been exceeded.

The constant spreading speed, which is reached very quickly after turning on the spin speed is switched, is not seriously endangered if the I. emptying of the vat is started at the same time, because the amount of water processed by the pump is not sufficient to cause a noticeable drop in the water level before a few tens of seconds have passed. Only the constant balancing speed due to the balance between the Motor torque and the moment of resistance caused by the friction of the water between the walls of the drum and the tub will be influenced. The size of these torques will determine the speed at which this constancy will show, and the duration of this constancy is to some extent determined by the amount of water processed by the pump to be determined. The constancy of the balancing speed will

0 I 3 '> ■ - ^: " . 1 3 Ä 0

BATH ORIGINAL

._ I

PHN.

- 13 -

maintained as long as the water level is a certain Value has not yet reached. The acceleration on The spin speed is then gradual and is a function of the water processed by the pump. This means great security in the event that the pump would get constipated; in this way it is always guaranteed that if the vat is not empty, the speed reached by the drum will never be the centrifugal ™

speed will be the same. If the vat has another Contains a not insignificant amount of water and the drum would rotate at a speed of 100 rev / min, the centrifugal force of the liquid would cause large irregularities bring about.

When the spin cycle of the laundry is finished, the motor is switched off, while known mechanical,

electric or electromagnetic means in effect occur to bring to a stop the drum after a few seconds, g thereby avoiding the occurrence of resonant vibrations in the moment of the critical speed is exceeded.

In a second exemplary embodiment of the washing machine according to the invention, the motor that drives the drum drives an induction direct current motor with permanent magnet, which is driven by an electronic speed control arrangement is fed. The rotating speeds of the drum are through determines the intensity of the current supplied to the Mqtor. For the maximum load corresponding to a

009840 / 13A0

PHN.

ten vat and a drum filled to the maximum, the current strength is in the order of magnitude of 5 A at a voltage of 20 V, reaching a speed of 50 rpm will. For a normally loaded drum, the spin speed is found to be around 1000 rpm, which is a Current intensity in the order of 3A at a voltage of 200 V corresponds. The amperage and voltage at a lower speed, e.g. the speed used for balancing, is due to this the frictional torque generated in the tub is automatically determined.

If the heating resistor is connected in series with the DC motor, the peak value of the is limited Starting current of the motor and one avoids that in the event an overvoltage of this motor a too high spin speed achieved.

Some of the measures described below are taken for a washing machine that is compatible with an above described motor is equipped, which is connected in series with a resistance element, which element for Limitation of the current strength is used.

The heating device located in the water is formed by two elements; one of them is one as usual in the heating circuit switched resistance with a thermostat and the other element is in series with the motor switched.

The feed block of the DC motor with a

009848/1340

Dauermagneton contains an adjustable potentiometer, with which the speed ^{can be regulated to 5 {} ) rpm (washing speed), as well as a potentiometer which can be reached on the control panel, with which the spin speed can be selected.

A machine which is equipped with a direct current motor with permanent magnets and which works according to the invention has numerous advantages. ■ g

During the Vaschgango, in which the motor torque is high, the high intensity of the current in the circuit causes a much larger voltage drop at the terminals of the heating element than at the terminals of the motor. On the other hand, one has to take into account two variable parameters, namely: the heating moment on the axis (amount of laundry in the drum »water level) and the mains voltage fluctuations (10 " ί. Above and I5 G below the nominal voltage). These parameters require the use of an electronic control device with - which makes it possible to compensate for differences in speed f. This device is formed by a thyristor bridge, the control electrodes of the thyristors being used to regulate the motor voltage.

The drum speed is this way regulated to + _ 5 t * min.

The regulation of the temperature of the washing water

is improved by the fact that the water is heated by the resistance element connected to the supply circuit of the Engine is lonely; the temperature of the water just remains by rotating the drum slowly while the

■ 0 C 9 8 /. 3 · '1 3 L 0

ORIGINAL INSPECTED

PHN ₄ kkü 8,

- Ιό -

sawtooth temperature control curve obtained by a thermostat is flattened, which improves the washing efficiency.

Switching to the spin speed takes place when the vat is filled with water. Before the Spin cycle, the drum rotates at a low speed and then the one determined by the program selector starts Spin cycle from washing speed.

Since the required torque is achieved by the fact that the vat is filled with water, is very large, there is almost immediately a balance between the power absorbed by the heating element and the motor and in this way one obtains a speed in of the order of 70 rpm for a few seconds is maintained, after which an acceleration for one second to reach an approximately constant speed of 200 rpm, which speed a few seconds long maintained; the reaction torque due to the movement of the water in the vat then diminishes and the speed is gradually increased to its maximum value. .

The excessive consumption is caused by the heating element taken in water (1200 W). As the speed increases, the torque and decreases also the power consumed.

The progressive spin makes it possible to reduce the counterweights on the vat.

009848/1340

PHN. ^ 08.

Braking after the spin cycle is achieved by using the motor as a generator on the one in the water Resistance to heating the water acts. From the maximum speed of the motor the drum becomes brought to a standstill in less than 5 seconds.

8/1340

Claims (1)

PHN. - 18 PATENT CLAIMS. 1. A method for washing and drying textiles in a combined washing machine and spinning machine that has one elastically suspended or supported tub with a rotatable about a horizontal or almost horizontal axis therein Drum, a drive device consisting of an electric motor for driving the drum with a washing machine and a Spin speed exists, a supply for this motor and transmission elements with a constant transmission ratio between the motor shaft and the drum shaftβ and Contains means for supplying and removing water, characterized in that that after the wash cycle, when the motor switches to spin speed and the drum accelerates while the vat is still filled with water, an intermediate speed is reached at which a Balance between the torque delivered to the drum shaft and its moment of reaction, which equilibrium is maintained until the water in the tub has started rotating and the reaction torque of the drum has become smaller, after which the acceleration of the drum is continued. 2. The method according to claim 1, characterized in that said intermediate speed is below the critical speed of the elastically suspended or supported part of the machine. . 3. The method of claim 1 or 2, wherein the Drum has a diameter of approx. 50 cm, which means that . .009.8487-1340 PHN. - 19 - shows that the mentioned intermediate speed is approx. 70 rev / min is. ■ '4, ancestors according to one of the preceding claims, characterized in that after the resumption of the acceleration of the drum, a second intermediate speed is reached which lies above the critical speed of the elastically suspended or supported part of the machine, which Zwischongeschwindigkeit only after the I water present is removed at least \ a part in Hott, is exceeded. 5. '■ \ experienced according to claim -V, wherein the drum has a diameter of approx. 50 cm, characterized in that that the mentioned second intermediate shaft speed is approx. 200 Γ min. (i. Viasch- and centrifugal machine to carry out of the method according to one of the preceding claims. 7. washing and centrifuging machine according to claim 0, characterized in that the drive motor is an asynchronous Two speed electric motor is. 8, washing machine and spinning machine according to claim 6, characterized in that the drive motor is a direct current motor and the feed device of the same contains a rectifier. Q »washing machine and spin dryer according to claim 8, _T characterized in that said motor is provided with a permanent magnet.
10. Washing machine and spin dryer according to claim 8 ■ 0 C 9 ^c u ? / i 2 ij3_ _ ORIGINAL INSPECTED 2 02 A 5.91 PHN. - 20 - or 9 »characterized in that a resistor with the Motor is connected in series, which resistor is in the vat. 11. Washer-extractor after one of the Claims 6-10, characterized in that the machine is provided with switching means that simultaneously switch the motor from the washing to the spinning speed and switch on the water drainage. 12 washing and spinning machine according to one of claims 6 - 10, characterized in that the machine is provided with switching means which switch on the water removal after the first intermediate speed is reached. 13. Washing and centrifuging machine according to one of claims 6-10, characterized in that the machine is provided with switching means which switch on the water drainage after the second intermediate speed has been reached is. 009848/1240 ORIGINAL IiSfSPECTED