GB2080836A

GB2080836A - Dry cleaning machine

Info

Publication number: GB2080836A
Application number: GB8117571A
Authority: GB
Original assignee: Mitsubishi Heavy Industries Ltd
Current assignee: Mitsubishi Heavy Industries Ltd
Priority date: 1980-06-09
Filing date: 1981-06-09
Publication date: 1982-02-10
Also published as: GB8331937D0; GB8331938D0; GB2138029A; GB2138029B; GB2141232B; DE3153272C2; DE3123386A1; IT1139366B; IT8122195A0; GB2080836B; GB2141232A; DE3123386C2

Abstract

A dry cleaning machine has a plurality of sealed chambers 2 fitted to a driven washing drum 1, a detecting means 13 for detecting the vibration of said washing drum and a fluid feed controlling means e.g. a computer 16, and valves 17, 17', 17'' for feeding predetermined amounts of a fluid to the above mentioned predetermined sealed chambers 2 on the basis of the results detected by said detecting means. The fluid is subsequently removed from the chambers 2 by opening of a valve 18 to supply compressed air through a central axial path. In another embodiment, Figs. 11 and 12 (not shown), this air path is omitted and predetermined amounts of liquid are enclosed in the chambers (2) which communicate with each other so that when predetermined amounts of compressed air are fed to the chambers the amount of liquid therein is adjusted. In a further embodiment, Figs. 13 and 15 (not shown), position detecting members (24) are provided on the rotary drum to cooperate with a position detector (28) at the same position as a vibration detector (25). <IMAGE>

Description

SPECIFICATION Dry cleaning machine This invention relates to improvements in dry cleaning machines.

Usually, in the case of washing a clothing with a dry cleaning machine, the clothing is put into a washing drum rotated by a drive source, is washed at a low speed rotation of the drum and then has the liquid removed by the centrifugal force by rotating said washing drum at a high speed. However, there have been defects that, when the liquid is removed, the clothing will be partially present and will not be uniformly distributed within the washing drum, therefore a large vibrating force will be generated by the partial load of the clothing in the washing drum, not only the machine life will be shortened but also the vibration of the machine will propagate to the surrounding through the installing ground base to cause a vibration trouble.

The countermeasures so far taken against them are largely divided into the following three: (i) To reduce the partial load of the clothing within the washing drum, (ii) To interrupt the vibration to the machine installing ground base and (iii) To reinforce the installing ground base.

As an example of the above mentioned countermeasure (i), there is a countermeasure wherein, in a cleaning machine of a horizontal rotary shaft, before the liquid is removed, the clothing within the washing drum keeps a centrifugal acceleration of substantially 1 G in the rotation (balance rotation) for a fixed time. By this countermeasure, the partial load of the clothing can be reduced to be substantially half but occasionally a large partial load will be generated. Therefore, it can not be said to be a sufficient countermeasure.

Further, as an example of the above mentioned countermeasure (ii), it is known to resiliently support the entire machine with an antivibration carriage formed of a spring and damper or to resiliently support only the washing drum part. By such countermeasure, the amount of the vibration transmitted from the machine to the ground base will be reduced to be a fraction of the conventional amount and the vibration trouble will be eliminated. But, on the other hand, the amplitude of the vibration of the resiliently supported entire machine or washing drum will increase, the piping within the machine will leak and the fastening parts will loosen. Thus, the countermeasure can not be said to be sufficient.

As an example of the above mentioned countermeasure (iii), there is a countermeasure wherein the machine is installed on the foundation of a large concrete block as to reduce the vibration of the ground base. However, there has been a defect that, in order to obtain a sufficient antivibration effect, the expenses required for the foundation work will be enormous.

The present invention is suggested with a view to providing a dry cleaning machine wherein all the defects and countermeasure difficulties of the above mentioned conventional dry cleaning machine can be eliminated and relates to a dry cleaning machine characterized by comprising a plurality of sealed chambers fitted to a washing drum rotated by a drive source, detecting means for detecting the vibration of said washing drum and a fluid feed controlling means for feeding predetermined amounts of a fluid to the above mentioned predetermined sealed chambers on the basis of the results detected by said detecting means.

Further, the present invention provides such method of preventing the vibration of a dry cleaning machine as is mentioned in this specification.

The present invention shall be concretely explained in the following with reference to the accompanying drawings in which: Figures 1 to 3 are schematic explanatory views of an embodiment of the present invention.

Fig. 1 is a general system view showing an essential part as vertically sectioned.

Fig. 2 is a sectioned view on line A-A in Fig. 1.

Fig. 3 is a sectioned view on line B-B in Fig. 1.

Figure 4 is a graph showing the relations between the number of revolutions of the washing drum and the vibration level transmitted to the ground base.

Figure 5 is a graph showing the detected values of the vibration obtained in case there is a partial load of the clothing in the position shown in Fig. 3 and the position signals of the base line.

Figure 6 is a view showing vectors of the balancing load weight by the liquid fed to each sealed chamber.

Figure 7 is a graph showing the relations between the liquid removing time and the weight of the clothing and liquid.

Figure 8 is a view showing an example of the time schedule of the automatic balance in case the present invention is applied.

Figure 9 is a graph showing the washing times, partial loads and vibration levels of the applied present invention and the conventional machine as compared with each other.

Figure 10 is a graph showing another example of the time schedule of the automatic balance.

Figures ii and 12 are schematic explanatory views of another embodiment of the present invention.

Figure 11 is a general system view showing an essential part as sectioned.

Figure 12 is a sectioned view on line C-C in Fig. 11.

Figure 13 is a block diagram showing an antivibration system in the other embodiment of the present invention.

Figure 14 is a partly magnified view of the computer in Fig. 13.

Figure 15 is a vertically sectioned view showing the details of the fluid feeding device in Fig.

13.

Figure 16 is a sectioned view on line D-D in Fig. 15.

Figures 17(A), (B) and (C) are signal wave form views of the respective parts in Figs. 13 and 14.

Figure 18 is a diagram showing the antivibration effects of this device.

Figure 19 is a block diagram of a partial load measuring method in the dry cleaning machine of the present invention.

Figure 20 is a characteristic diagram showing the output characteristics of the amplifier and the characteristics and output characteristics of the quadratic analogue filter.

In Figs. 1 and 2, 1 is a rotary washing drum and 2, 2' and 2" are plurality (three in the case of this embodiment) of sealed chambers arranged at regular intervals along the peripheral direction on the outer periphery of said washing drum. 3 is a rotary shaft of the washing drum 1. This rotary shaft 3 is rotatably borne by bearings 4 and 5, is to be rotated by a proper drive source (not illustrated) through a pulley 6 secured to its outer end and is to rotate in a predetermined direction the washing drum 1 secured to its inner end together with the sealed chambers 2, 2' and 2".

7, 8 and 9 are rotary joints for a liquid arranged on the outer periphery of the rotary shaft 3 as shown in Fig. 1. 10 is a rotary joint for air. 11, 11' and 11" are liquid paths provided along the axial direction (the direction vertical to the paper surface in Fig. 2) within the rotary shaft 3 as shown in Fig. 2. 12 is an air path provided along the axial direction in the center of the rotary shaft 3 and communicating at the outer end with the above rhentioned rotary joint for air and at the inner end with the above mentioned sealed chambers 2, 2' and 2". 13 is a vibration detecting means (vibration detector) fitted outside the top of a casing K enclosing the washing drum 1. The vibration of the partial load 14 of the clothing within the washing drum 1 is to be detected by this vibration detecting means 13. (See Fig. 3).

15 is a base point detector fitted to the casing K as shown in Fig. 1. The signal of the base point on the washing drum 1 is to be given by this base point detector 15. 16 is a computer electrically connected to the above mentioned vibration detecting means 13, valves 17, 17' and 17" for the liquid and a valve 18 for air.

The valves 17, 17' and 17" for the liquid are arranged in the courses of the pipings communicating respectively with the above mentioned sealed chambers 2, 2' and 2" so that, when the respective valves 17, 17' and 17" for the liquid are opened by the output of the computer 16 side for a required time, any amounts of the liquid may be introduced into the above mentioned respective sealed chambers.

Further, after the liquid is removed, while the liquid within the respective sealed chambers 2, 2' and 2" is subjected to a centrifugal acceleration more than 1 G, the valve 18 for air will open, compressed air will be fed under pressure into the respective sealed chambers 2, 2' and 2" through the rotary joint 10 for air and the air path 12 and the liquid within the respective sealed chambers 2, 2' and 2" will be able to be forcibly discharged out of the chambers.

An embodiment of the dry cleaning machine of the present invention is formed as mentioned above. First of all, the vibration is measured at a number of revolutions (number of intermediate liquid removing revolutions) of the washing drum at which the centrifugal acceleration given to the clothing within the washing drum is larger than 1 G and the vibration is so low as not to be a problem. Fig. 5 shows the detected values of the vibration and base point position signals by the vibration detector 13 and base point detector 15 obtained in case the partial load of the clothing is in the position 14 shown in Fig. 3. In the drawing, T denotes a time for which the washing drum makes one rotation and t denotes a time difference between the vibration maximum value detection and base point detection. From Fig. 5, the size of the partial load and the angle 8 between the base point and partial load are determined as follows: Partial load = C x E where C: Constant determined by experiments and E: Value of the vibration amplitude as converted to an electric amount.

Angle (rad.) = a-t/T X 2s where a: Angle between the base point detector and vibration detector.

The amounts of the liquid to be introduced into the respective sealed chambers 2, 2' and 2" provided on the outer periphery of the washing drum in order to be balanced with this partial load are obtained by computing the vectors shown in Fig. 6.

In Fig. 6, UB denotes a partial load (in kg.) of the clothing, F denotes a weight (in Kg.) of the balancing load by the liquid entering the chamber 2 (F = O in Fig. 6), F' denotes a weight (in kg.) of the balancing load by the liquid entering the chamber 2' and F" denotes a weight (in kg.) of the balancing load by the liquid entering the chamber 2".

As shown in Fig. 7, at the intermediate liquid removing revolutions, the clothing contains a large amount of the liquid and the amount of the partial load is larger than at the time of the shift to the liquid removing revolutions. In the example of the time schedule of the automatic balance shown in Fig. 8, there is taken an idea whereby the liquid is balanced with the partial load when the revolutions shift to the liquid removing revolutions in advance at the intermediate liquid removing revolutions. The balancing loads P, P' and P" by the liquid to be put into the respective chambers 2, 2' and 2" when the revolutions are shifted to the liquid removing revolutions are determined as follows: P = K x F, P' = K X F' and P" = K x F" where K is a constant determined by experiments.

The amounts of the liquid to be put into the respective chambers 2, 2' and 2" are computed by the computer 16 from these balancing load values and the liquid is put into the respective chambers 2, 2' and 2" by opening the respective valves 17, 17' and 17" for the required time to correct the unvalance caused by the partial load.

This operation is continued two or three times as required. In case the remaining partial load reduces to be less than a predetermined value, the revolutions will be shifted to the liquid removing revolutions. By the way, the predetermined value so called here is not a constant value but a value obtained by multiplying the first detected partial load (C X E) by a constant less than 1.

After the revolutions are shifted to the liquid removing revolutions, the liquid contained in the clothing will be further removed and the remaining partial load will become large again.

Therefore, the vibration is measured with the liquid removing revolutions to correct the unbalance.

After the end of the liquid removal, the revolutions are shifted again to the intermediate liquid removing revolutions. While the liquid within the respective chambers 2, 2' and 2" is adhering to the outer walls, the respective valves 17, 17' and 17" are opened, compressed air is fed into the respective chambers 2, 2' and 2" and the liquid is carried out of the respective chambers.

Fig. 10 shows another example of the time schedule of the automatic balance of the cleaning machine to which the present invention is applied. In this example, as soon as the washing ends, the revolutions are shifted to the liquid removing revolutions to correct the unbalance. In such case, the amounts of the liquid to be put into the respective chambers 2, 2' and 2" are computed from the values of the above described balancing loads F, F' and F", the liquid is put into the respective chambers by opening the respective valves 17, 17' and 17" for the liquid for the required time and the unbalance can be corrected.

Fig. 9 shows the difference in the practical effects between the cleaning machines to which the present invention is applied and a conventional machine. In the graph, the solid line represents the remaining unbalanced weight in working the present invention, the broken line represents the remaining unbalanced weight of the conventional machine, the one-dot chain line represents the ground base vibration level in working the present invention and the two-dot chain line represents the ground base vibration level of the conventiona; machine. As understood in this graph, according to the present invention, the remaining unbalanced weight reduces to be less than 1/5 that of the conventional machine, the ground base vibration level lowers by more than 14 dB and the ground base vibration problems can be perfectly solved.

After the end of the liquid removal, the liquid in the respective sealed chambers 2, 2' and 2" is frocibly discharged out of the chambers. Therefore, in a cleaning machine of a type in which, after the liquid is removed, the clothing is dried with wind, there is an advantage of consuming no excess heat.

By the way, in the above mentioned embodiment, it is possible that the airpath 12 is made a liquid path, the valves 17, 17' and 17" are converted to be for compressed air, a liquid is poured in advance into the sealed chambers 2, 2a and 2b through the rotary joint 10 and path 12, compressed air is fed into the respective chambers through the valves 17, 17' and 17" by the signal obtained from the computer 16 and any amounts of the liquid in the respective chambers are thereby discharged to correct the unbalance.

Another embodiment of the dry cleaning machine of the present invention is shown in Figs.

11 and 12. This is an embodiment wherein, in the embodiment shown in Fig. 1 and 2, predetermined amounts of the liquid are enclosed in advance in the respective sealed chambers 2, 2a and 2b which are made to communicate with one another through communicating pipes 19, 1 9a and 1 9b and the valves 17, 17' and 17" are made for air. The valves for air are opened and closed by the signal from the computer 16 and predetermined amounts of compressed air are thereby fed into the respective sealed chambers 2, 2a and 2b to adjust the amounts of the fluid in the respective sealed chambers. Thereby, the rotary joint 10 for air, air path 12 and valve 18 for air are eliminated.

In each sealed chamber, the liquid of about 2/3 the volume of the chamber is enclosed.

When the above mentioned valves 17, 17' and 17" are opened for a fixed time, the air pressures in the respective chambers will vary and any amounts of the liquid in the respective chambers will be able to be moved between the respective chambers.

The present invention further relates to a rotary drum vibration preventing device characterized by comprising a plurality of sealed chambers provided along the periphery of a rotary drum, position detecting members provided respectively to correspond to the above mentioned sealed chambers, a position detecting means provided on the fixed side and detecting the passage of the above mentioned position detecting members, an amplitude detecting means detecting the amplitude of the above mentioned rotary drum as synchronized with the detecting signal of the above mentioned position detecting means, sealed chambers to be fed with a fluid and an operating circuit operating the amounts of the fed fluid on the basis of the detecting signals of the above mentioned position detecting means and amplitude detecting means and a fluid feeding means selectively feeding the fluid to the above mentioned sealed chambers on the basis of the output of the above mentioned operating circuit.

An embodiment of this invention is illustrated in Fig. 13 to 18.

First, in Figs. 13 to 16, 21 is a rotary drum coaxially loosely inserted in a fixed drum 22, 23, 23a and 23b are sealed chambers of the same shape secured respectively at center angles of 120 degrees along the periphery of the rotary drum 21, 24, 24a and 24b are position marks respectively provided to projection the sealed chambers 23, 23a and 23b and rotating integrally with the rotary drum 21, 25 is a vibration detector provided on the fixed drum 22 and detecting the vibration of the rotary drum 21, 26 is an amplifier amplifying the output of the vibration detector 25, 27 is an Ad converter digitally converting the output of the amplifier 26, 28 is a position detector provided in the same position as of the vibration detector 25 on the fixed drum 22 and detecting the passage of the position marks 24, 24a and 24b provided to project on the rotary drum 21 and 29 is a position reading device putting in the output of the position detector 28 and reading the distinction of the position marks 24, 24a and 24b.

30 is a timer. 31 is a computer putting in the respective outputs of the AD converter 27, position reading device 29 and timer 30 and operating the sealed chambers to which the fluid is to be fed in the below mentioned manner and the amounts of the fed fluid. 32 is a controlling device controlling a fluid feeding device 33 with the output of the computer 31.

34, 34a and 34b are pipe lines feeding the fluid respectively to the sealed chambers 23, 23a and 23b from the fluid feeding device 33.

35 is a synchronizing device putting in and out the digital signal put out of the AD converter 27 only when the output signal of the position reading device 29 is received. 36 is a vibration output memorizing device memorizing the data from the AD converter 27 received by the synchronizing device 35. 37 is an average value operating and memorizing device operating and memorizing the respective average vibration amplitude values of the position marks 24, 24a and 24b from the data put out of a vibration output memorizing device 36. 38 is a fluid fed sealed chamber determining and memorizing device determining and memorizing the sealed chamber to be fed with the fluid to compensate the unbalance of the rotary drum from the average vibration amplitude put out of the average value operating and memorizing device 37.

39 is a fluid feed amount operating and memorizing device operating and memorizing the fluid amount to be fed to the fluid fed sealed chamber from the average vibration amplitude put out of the average value operating and memorizing device 37 and the output of the fluid fed sealed chamber determining and memorizing device 38. 40 is a fluid feeding time operating and watching device operating the operating time of the fluid feeding device 33 to feed the fluid fed sealed chamber with the fed fluid amount put out of the fluid feed amount operating and memorizing device 39 and watching that, by the timer 30, the fluid deeding device controlling device 32 puts out the above mentioned operating time operating signal to the fluid feeding device 33.

41 is a hollow shaft coaxially pivoted to the fixed drum 22 by bearings 42 and 43, secured at one end to the axis of rotary drum 21 and fitted at the other end with a pulley 44. The hollow shaft 41 is provided with fluid paths forming pipe lines 34, 34a and 34b communicating respectively with the sealed chambers 23, 23a and 23b.

45, 46 and 47 are rotary joints fluid-tightly enclosing the hollow shaft 41 fixed to the fixed drum 22 side and communicating respectively with the pipe lines 34, 34a and 34b. 48 is a rotary joint for air attached to the right end of the hollow shaft 41. 49, 49a and 49b are respectively fluid controlling electromagnetic valves. 50 is an air controlling electromagnetic valve. 51 is an outer peripheral equivalent partial load (which shall be called a partial load hereinafter) generated by the rotation of the rotary drum 21.

In such device, when the rotary drum 21 rotates, the vibration of the rotary drum 21 caused by the partial load 51 generated as synchronized with the rotation of the rotary drum 21 will be detected by the vibration detector 25, will be amplified by the amplifier 26, will be converted to a digital signal by the AD converter 27 and will then enter the computer 31.

On the other hand, the position detector 28 will distinguish the detecting signals by the position marks 24, 24a and 24b of the rotary drum 21 and the signals will be matched through the position reading device 29 and will then enter the computer 31.

As shown in Fig. 14, the digital signal of the AD converter 27 put into the synchronizing device 35 and the output signal of the position reading device 29 will be resepctively Of the wave forms shown in Figs. 17(A) and (B). The output of the synchronizing device 35 putting out the output of the AD converter 27 only when the output signal of the position reading device 29 is put in will be of the wave form shown in Fig. 17(C).

In such case, if the data 52, 53, 54, 55, 56 and 57 received by the synchronizing device 35 are made respectively x, X2x, X3a, x12, x22 and x32, the data obtained at the nth time will be represented by x1n, x2n and x3n. Here, x11 (i = 1 to n) is a vibration amplitude value corresponding to the position mark 24 in Fig. 13. In the same manner, x2 (i = 1 to n) and x3 (i = 1 to n) are vibration amplitude values corresponding respectively to the position marks 24a and 24b.

The average vibration amplitude is operated in the average value operating and memorizing device 37 in Fig. 14 fundamentally by the below mentioned formulas (1) to (3). However, in the device of this embodiment, for convenience sake, as the vibration detected by the vibration detector 25 is represented by y = A sin (t + 0), the following formulas (4) to (6) are used:

X, = x,-d/3 (4) X2 = x2-d/3 (5) X3=x3-d/3 (6) where d = x, + x2 + x3 (7) In this embodiment, the average vibration amplitude values X1, X2 and X3 represent respectively the values when detected of the position marks 24, 24a and 24b.

The fluid fed sealed chamber determining and memorizing device 38 in Fig. 14 will determine to feed the fluid to the other sealed chambers than the sealed chamber (23, 23a or 23b) corresponding to the position mark showing the maximum value Xm (m = 1, 2 or 3) among X1, X2 and X3. For example, if X, is larger than X2 and X3, it will be determined to feed the fluid to the other sealed chambers 23a and 23b than the sealed chamber 23 corresponding to the position mark 24 corresponding to X,.

The fluid feed amount operating and memorizing device 39 is to operate the fluid feed amounts by putting in X1, X2 and X3. In the above embodiment, they will be as in the following formulas (8) to (10).

Amount of fluid fed to the sealed chamber 23a = k X (-2/3 (2X2 + X3)) (8) Amount of fluid fed to the sealed chamber 23b = k X (-2/3 (2X3 + X2)) (9) Amount of fluid fed to the sealed chamber 23=0 (10) where k is a fluid feed amount converting coefficient and the values within the parentheses { } of the formulas (8) and (9) are represented by the voltage values or numbers of bits, are therefore converted to the volumes or weights of the fluid and are memorized.

The fluid feeding time operating and watching device 40 will convert the fed fluid amount to the operating time of the electromagnetic valve. The fluid feeding device controlling device 32 will switch on and off the electromagnetic valves 49, 49a and 49b. The operating signal will be put out by the timer 30 to the fluid feeding device 33 for the operating time. Therefore, the fed fluid amounts of the fluid will be fed into the sealed chambers 23, 23a and 23b respectively through the pipe lines 34, 34a and 34b and the rotary drum 21 will be balanced.

In Fig. 18, the solid line represents the antivibration effect of the present invention. The partial load by the present invention will reduce from the level 60 to level 59 and from the level 59 to level 58 with the lapse of time. By the way, the broken line represents the partial load in case the present invention is not worked.

In the dry cleaning machine of the present invention, the partial load of the washing drum can be measured by the following method.

It is a method of measuring the partial load of a rotary drum wherein the vibration of the drum is taken out as a vibrating force F represented by the following formula (11) by using an acceleration meter, then this output signal is amplified and then only the signal corresponding to the partial load m is taken out through a quadratic analogue filter having the characteristics of the below mentioned formula (12): F=mrw2 (11) where F is a vibrating force, r is a radius of the drum and U is an angular velocity and (KA a'2c)/(co2o + 24002XT;f + 2a7jf2) (12) where KA is an adjusting coefficient, Z0 is an interrupted frequency, E is a tamping coefficient, f is a frequency and j is ç 1.

Conventionally, in the case of measuring this kind of rotary drum, the vibration of the rotary drum is measured and the partial load is measured on the basis of this measured value. That is to say, the acceleration meter is used to measure the vibration of the rotary drum. The output signal is obtained as proportional~ to the vibrating force F = mrx2 where F is a vibrating force, m is an equivalent concentrated partial load (which shall be called a partial load hereinafter), r is a radius of the rotary drum and co is an angular velocity of the rotary drum.Therefore, in order to measure the partial load m, it is necessary to cancel w. Particularly, in case the angular velocity of the rotary drum varies, the correction by the angular velocity will have to be made and will be inconvenient. Further, as the output signal of the acceleration meter is proportional to the square of the angular velocity of the rotary drum, there is a defect that, if the angular velocity of the rotary drum is small, the measured degree will be low.

By the above mentioned method, the partial load of the rotary drum can be easily precisely detected irrespective of the angular velocity.

The invention shall be explained in the following with reference to Figs. 19 and 20.

First, the vibration of the rotary drum is taken out as a vibrating force F by using an acceleration meter 62. The vibrating force F is represented by the following formula: F = mrç2 where r is a radius of the rotary drum and X is an angular velocity of the rotary drum.

Then, the signal detected by the acceleration meter 62 is amplified through an amplifier. The output characteristic of this amplifier 63 is proportional to the angular velocity of the rotary drum as shown by the straight line a in Fig. 20.

The output signal of the amplifier 63 is sent to a quadratic analogue filter 64 which has a characteristic of the following formula: (KA.a'2J/(a'20 + 2#02':'jf +#2#2) where KA is an adjusting coefficient, Z0 is an interrupted frequency, ( is a tamping coefficient and f is a frequency. This characteristic is graphed as the curve b in Fig. 20.

The signal having passed through this quadratic analogue filter 64 shows such output characteristic as is shown by the curve c in Fig. 20. Therefore, if the interrupted frequency w, and frequency f are so selected that the angular velocity of the rotary drum 61 may come to the flat part of the curve c, the amplitude value shown by the output signal of the quadratic analogue filter 64 will be obtained as proportional to the partial load m irrespective of the angular velocity of the rotary drum 61.

As in the above, according to this method, by using the quadratic analogue filter, the amplitude value proportional to the partial load of the rotary drum is obtained without making the correction by the angular velocity and, in case the angular velocity is low, the measuring precision will improve.

Claims

1. A dry cleaning machine characterized by comprising a plurality of sealed chambers fitted to a washing drum rotated by a drive source, a detecting means for detecting the vibration of said washing drum and a fluid feed controlling means for feeding predetermined amounts of a fluid to the above mentioned predetermined sealed chambers on the basis of the results detected by said detecting means.

2. A dry cleaning machine according to claim 1 wherein the above mentioned sealed chambers are filled in advance with a liquid and predetermined amounts of compressed air are fed into the sealed chambers on the basis of the detected results of the above mentioned detecting means to discharge predetermined amounts of the liquid out of said sealed chambers.

3. A dry cleaning machine according to claim 1 wherein predetermined amounts of a fluid are enclosed in the above mentioned sealed chambers, the respective sealed chambers are made to communicate with one another through communicating pipes and predetermined amounts of compressed air are fed into the sealed chambers on the basis of the detected results of the above mentioned detecting means to move the liquid between the respective sealed chambers.

4. A device for preventing the vibration of a rotary drum in a washing machine characterized by comprising a plurality of sealed chambers provided along the periphery of a rotary drum, position detecting members provided respectively to correspond to the above mentioned sealed chambers, a position detecting means provided on the fixed side and detecting the passage of the above mentioned position detecting members, an amplitude detecting means detecting the amplitude of the above mentioned rotary drum as synchronized with the detecting signal of the above mentioned position detecting means, sealed chambers to be fed with a fluid and an operating circuit operating the amounts of the fed fluid on the basis of the detecting signals of the above mentioned position detecting means and amplitude detecting means and a fluid feeding means selectively feeding the fluid to the above mentioned sealed chambers on the basis of the output of the above mentioned operating circuit.

5. A method of measuring the partial load of a rotary drum wherein the vibration of the drum is taken out as a vibrating force F represented by the following formula (1) by using an acceleration meter, then this output signal is amplified and then only the signal corresponding to the partial load m is taken out through a quadratic analogue filter having the characteristics of the below mentioned formula (2): F=mrx2 (1) where F is a vibrating force, r is a radius of the drum and X is an angular velocity and (KA.a'2o)/(C()2o + 2So 2sTjf + 2': :'jf2) (2) where KA is an adjusting coefficient, U0 is an interrupted frequency, 5 is a tamping coefficient, f is a frequency and j is < 1.