AU639215B2 - Vacuum cleaners having dirt sensors - Google Patents

Description

639215 COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 COMPLETE SPECIFICATION NAME ADDRESS OF APPLICANT: Hoover PLC Dragonparc, Merthyr Tydfil Mid-Glamorgan South Wales CF48 1PQ United Kingdom NAME(S) OF INVENTOR(S): Bryce D. McMichael Darwin S. CROUSER ADDRESS FOR SERVICE: DAVIES COLLISON Patent Attorneys 1 Little Collins Street, Melbourne, 3000.

COMPLETE SPECIFICATION FOR THE INVENTION ENTITLED: Vacuum cleaners having dirt sensors The following statement is a full description of this invention, including the best method of performing it known to me/us:la 1 2 3 The present invention relates generally to vacuum 4 cleaners and more particularly, to a vacuum cleaner having a sensor for detecting the presence of dirt in 6 an airflow passageway therein.

7 Vacuum cleaners are widely used to clean dirt and 8 debris from carpets, fabrics and various other 9 materials and surfaces. A vacuum cleaner generates a flow of air through a passageway one end of which 11 defines an inlet and is presented to the vicinity of 12 the dirt and debris. The airflow generated by the 13 vacuum cleaner carries the dirt and debris into the

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14 passageway inlet subsequently to be trapped or collected in a suitable container or bag for subsequent 16 disposal.

17 A problem associated with using a vacuum cleaner 18 is determining when the area being cleaned is 19 substantially free of dirt and debris. Generally, on bare surfaces, the operator can visually inspect the 21 area and determine whether further cleaning is 22 necessary. For carpeting, fabrics and other surfaces, 23 however, the dirt may not easily be visible to the 24 operator; instead it may be trapped within the carpet fibres or the like. The operator, then, can merely 26 operate the vacuum cleaner over an area for a period of 27 time believed to be sufficient to remove the dirt and 28 debris. Depending on the particular situation, 29 however, the time period may be inadequate, resulting in dirt and debris being left in the carpet or the 31 like. Alternatively, the time period may be unduly 32 protracted, which results in an inefficient use of time 33 and energy to clean a particular area. This may also 2 1 result in increased wear of the carpet itself.

2 In addition to the foregoing, it may be desirable 3 to regulate the operation of the vacuum cleaner in 4 response to the presence of dirt and debris. For mildly soiled areas, the cleaner may be operated at a 6 reduced power setting to conserve energy and to lessen 7 wear of the cleaner components as well as of the carpet 8 or the like. When heavily soiled areas are 9 encountered, it may be desirable to increase the power of the cleaner to extract the dirt and debris more 11 effectively. After such area is cleaned, the power 12 setting can again be reduced. 13 In the past, the selection of the various power 14 settings of the cleaner has been controlled by the operator. However, as discussed hereinabove, the 16 ability of the operator to detect dirt and debris on 17 many surfaces significantly is limited, such that the 18 cleaner often is operated at less than optimum power 19 levels for the areas being cleaned.

Efforts have been proposed to assist the operator 21 in detecting whether dirt and debris is being extracted 22 from the area being cleaned. Such efforts include 23 providing a thin diaphragm within an opening in the 24 wall of the vacuum cleaner airflow passageway, preferably at a bend in the passageway. The diaphragm 26 is so constructed and positioned that particles passing 27 through the airflow passageway impinge against the 28 diaphragm thereby creating an audible sound. The 29 operator listens for such audible sound as an indication that dirt and debris are being removed from 31 the area. The operator may then continue cleaning the 32 area until the audible sound ceases, indicating thfi 33 area is clean. Similarly, the operator can control the 3 1 power setting of the cleaner, as heretofore discussed, 2 in response to the audible sound created by the dirt 3 and debris impinging against the diaphragm.

4 While the foregoing system may be helpful in detecting dirt and debris, it is ineffective due to 6 several inherent shortcomings. Specifically, the 7 system requires the diaphragm to be exposed directly to 8 the airflow through the passageway. This requires a 9 special mounting and/or amplifying assembly resulting in a more cumbersome, complex and expensive passageway.

11 Furthermore, such direct exposure significantly 12 increases the risk that the thin membrane of the 13 diaphragm -may be damaged by heavier or sharp objects 14 carried into the passageway by the airflow.

The prior system also requires the diaphragm to be 0 16 positioned near the user, to enable the user to hear 17 the audible sound over the cleaner and other 18 environmental noises. Accordingly, such a system may 19 be usable with canister-type cleaners but not with conventional upright cleaners. Furthermore while 21 heavier material, such as sand, may produce a 22 recognisable sound upon impinging the diaphragm, other 23 lighter material, such as dust, would be less able to 24 produce such a sound. Indeed, some material impacting the diaphragm may generate sound waves outside the 26 frequency range of the human ear. Accordingly, the 27 operator remains uncertain whether or not the specific 28 area has been thoroughly cleaned.

29 Attempts to detect dirt in the airflow using photoelectric sensors also have proved ineffective. It 31 is difficult to calibrate the sensitivity of such 32 sensors accurately to detect heavier sand as well as 33 fine dust and talc. Furthermore, the sensor must be -4exposed to the airstream with the attendant risk of damage to the sensor components. An additional shortcoming of this system is found in the occlusion of the sensor from accumulated dirt film after a period of operation of the cleaner. Once occluded, the sensor becomes ineffective to detect dirt in the airflow.

Despite the attempts to provide a vacuum cleaner which enables the operator to determine the cleanliness of a particular area, none has yet resulted in a cleaner which provides a reliable dirt indicator easily identifiable by the operator. Furthermore, no system has provided a control for the operation of the cleaner in response to the existence of dirt and debris encountered in the area being cleaned.

It is, therefore, a primary object of the present invention to provide a vacuum cleaner having a sensor which reliably indicates the presence or absence of dirt and debris being removed from an area being cleaned.

According to one aspect of the present invention, a vacuum cleaner comprises suction means for creating an airflow for transporting dirt from a surface being cleaned, duct means for conveying the dirt laden airflow therethrough, and sensing means responsive to interaction between the duct means and the dirt flowing therethrough for producing a first electrical signal representative of dirt within the airflow.

According to another aspect of the present invention there is provided a method for controlling the operation of a vacuum cleaner having a motor for creating an airflow for transporting particulate matter through an air duct, comprising the steps of: generating a first electrical signal by sensing means responsive to interaction .between the duct means and particulate matter in the airflow; processing the first electrical signal; establishing preselected parameters for the first electrical signal; and generating a second electrical signal when the first electrical signal meets the preselected parameters.

The invention thus makes possible a vacuum cleaner having a sensor which is not 930513,p:Aopcigcp,45823.,4 exposed to the airflow in the passageway of the cleaner and in which the sensor may be located remote from the operator while generating a signal perceivable by the operator.

Preferably, the operation of the cleaner is controlled, at least in part, by the signal generated by the sensing means.

The sensing means may take various forms but preferably is a piezoelectric sensor arranged to detect vibrations set up by the passage of dirt through the duct. These vibrations may be in the form of the sound of the air in the airflow or mechanical from the impact of the dirt particles against the interior surfaces of the duct. Alternatively, the sensing means may sense electrostatic charge created by movement of the air through the duct.

Preferably, there are processing means to receive the first electrical signal and to generate a second electrical signal when the first electrical signal meets preselected parameters. For example, the preseleced parameters may include the first electrical signal having a pulse amplitude of at least 24 millivolts and a pulse width of approximately 50 microseconds and may include the first electrical signal having at least three pulses within an interval of approximately ten seconds.

The invention may be carried into practice in a e 930513,p:\opc\gcp,45823c,5 6 1 various ways but one vacuum cleaner embodying the 2 invention will now be described by way of example with 3 reference to the accompanying drawings, in which: 4 Fig. 1 is a perspective view of the vacuum cleaner with parts thereof broken away to depict a mounting 6 location for a dirt sensor; 7 Fig. 2 is an enlarged, fragmentary cross-section 8 of the air duct of the vacuum cleaner depicted in Fig.

9 1; and, Fig. 3 is a schematic block-diagram for a circuit 11 for processing the signal of the sensor employed by the 12 vacuum cleaner depicted in Fig. 1.

13 The vacuum cleaner 10 shown in Figure 1 is of the 14 kind known as an upright cleaner and includes a base 11, and an upper housing 12 and handle 13, together 16 pivotally connected to thF base 11. The base 1.1 houses 17 a cleaner motor, an intake airflow duct and a nozzle 18 with an opening beneath the base 11 to engage the 19 floor. Contained within the upper housing 12 is a substantially rigid exhaust airflow duct 14 which 21 connects the exhaust port of the cleaner motor with a 22 filter bag 15 contained within a cleaner jacket 16.

23 The specific arrangement of the internal 24 components of the cleaner .10 can be considered, in greater detail, with reference to Fig. 2.

26 Specifically, a sensor or transducer 20 is secured to 27 the air duct 14, and preferably to the outer surface 28 thereof. The transducer 20 may be one of a variety of 29 sensors which accurately detect acoustical and/or mechanical vibrations in the frequency range of 31 approximately 3 KHz to approximately 20 KHz or higher.

32 It has been found that an acceptable transducer 20 can 33 be fabricated from thin-film piezoelectric material, 7 1 such as polyvinylidene fluoride (PVDF) film, having a 2 thickness of approximately 20 Am. The PVDF film is 3 metallized on both sides and electrically poled during 4 manufacture. A suitable transducer 20 may be constructed from Pennwalt "KYNAR" Piezo Film, 28 im 6 thickness, available from Pennwalt Corporation, King of 7 Prussia, Pennsylvania ("KYNAR" is a trade mark of 8 Pennwalt Corporation). The planar area of the 9 transducer 20 will depend upon the specific application; but a transducer 20 measuring 11 approximately 0.75 inch (1.9 cm) by 1.375 inches 12 cm) has been found to produce acceptable results.

13 The transducer 20 preferably is adhesively mounted 14 to the air duct 14. While a number of different adhesives may be usable, it is desired that an adhesive 16 be selected which will provide a secure mechanical bond 17 between the transducer 20 and air duct 14.

18 Additionally, the adhesive bond should not impede the 19 transmission of acoustical stimuli to the transducer 20, as will be appreciated hereinbelow. For this 21 purpose, a thin layer of silicone adhesive, 22 approximately 2 mils (0.05 mm) thick, such as RTV 23 Silicone Adhesive/Sealant, available from General 24 Electric Co., Waterford,. New York, has proved to be quite acceptable.

26 The location of the transducer 20 on the air duct 27 14 will depend upon the specific application and may be 28 located on the interior or exterior of the air duct 14, 29 although as discussed hereinabove, the exterior of the air duct 14 is preferred. The transducer 20 may be 31 located upstream of the cleaner motor, near the nozzle 32 inlet or, as described, it may be located downstream of 33 the motor, near the bag outlet of the air duct 14. In 8 1 the cleaner being described, the transducer 20 is 2 mounted on the exterior surface of the air duct 14 3 approximately at the midpoint of the outside arc of a 4 900 elbow although other locations may be acceptable.

Such a location, on an air duct 14 having a wall 6 thickness of between 0.020 and 0.030 inch (0.5 and 0.8 7 mm), has been found to enable the transducer 8 accurately to detect the presence of dirt and debris 9 passing through the air duct 14, as will be appreciated hereinbelow.

11 Located elsewhere within the vacuum cleaner 10 and 12 preferably in the proximity of the air duct 14 within 13 the upper housing 12 is a control module 21. In this 14 example, the control module 21 is mounted adjacent the handle 13 within the upper housing 12; but, again, the 16 specific location may vary depending upon the 17 particular cleaner. The control module 21 is 18 electrically interconnected with the transducer 20 by 19 an input lead 22. As will be appreciated hereinbelow, the control module 21 is suitable for controlling the 21 operation of the cleaner 10 in response to the signal 22 received from the transducer 23 An indicator light 23 may be mounted in the upper 24 wall 24 of the housing 12 and is electrically interconnected with the control module 21 by leads 26 The indicator light 23 preferably is a low voltage, low 27 current draw indicator, such as a light emitting diode 28 (LED), which is controlled by the module 21 to indicate 29 the passage of dirt and debris through the air duct 14; as will be discussed hereinbelow. It should be noted 31 that the indicator light 23 need not necessarily be an 32 LED as other visual or audible signalling devices ate 33 likewise contemplated. Furthermore, the indicator 9 1 light 23, or any other signalling device, may be 2 omitted completely and, instead, the module 21 may be 3 used only to control the operation of the cleaner 4 as will be appreciated hereinbelow.

The control module 21, and specifically the 6 circuit logic thereof, can be more fully appreciated 7 with reference to Fig. 3. The control module 21 is 8 represented generally by the broken line and is shown 9 interconnected with the transducer 20 through the input lead 22, with the indicator light 23 through the leads 11 25, and with a cleaner motor 26 through a motor lead 12 27. As configured, the control module 21 is capable of 13 activating the indicator light 23 and controlling the 14 performance of the motor 26 in response to the presence of dirt and debris in the air duct 14 as sensed by the 16 transducer 20. It should be appreciated that many 17 different circuits can be assembled for the control 18 module 21 by one skilled in the art of electronics.

19 The output signal from the transducer 20 is a low voltage AC signal. This signal is received and 21 amplified by a first conventional signal amplifier 22 A gain adjuster 31 may be interconnected with the first 23 signal amplifier 30 to provide sensitivity adjustment.

24 In such manner spurious signals from the transducer can be reduced such that only signals indicative of 26 dirt and debris in the air duct 14 are processed by 27 control module 21.

28 The afplified signal of the first amplifier 30 is 29 received by a second conventional signal amplifier 32.

This re-amplified signal is then introduced to a 31 typical pulse stretch amplifier 33 which increases the 32 pulse width of the signal for further processing.

33 Specifically, the signal from the first amplifier 1 may have a pulse width of approximately 50 to 160 2 microseconds which can then be increased with the pulse 3 stretch amplifier 33 to a pulse width of approximately 4 5 to 20 milliseconds.

The signal from the pulse stretch amplifier 33 is 6 received by an integrator/timer 34 suitable to activate 7 the system in response to recurring signals of 8 sufficient duration which are indicative of a sustained 9 presence of dirt in the air duct 14. Thereafter, the integrator/timer 34 maintains activation of the system 11 for a preselepted time interval following termination 12 of the signal generated by the sensor 20. This avoids 13 repetitive activation/deactivation of the system with 14 each passing signal. The system can be set to activate when approximately three to five pulses are sensed 16 within an interval of approximately ten seconds. These 17 parameters generally are indicative of sustained 18 concentration of dirt in the airflow through the air 19 duct 14. The time interval after activation of the system may vary with the particular applications; but 21 a range of approximately one to five seconds has been 22 found to be acceptable with a period of approximately 23 three seconds being preferred. The time interval may 24 be variable to the user or, more preferably, it may be fixed at the time of assembly of the cleaner 26 The output signal from the integrator/timer 34 is 27 once again amplified by a conventional driver amplifier 28 35 which amplifies the signal to generate a usable 29 output signal. Such output signal preferably is approximately 3.0 to 4.5 volts, which may then be 31 used to power the indicator light 23, as heretofore 32 described. Similarly, the output signal may be 33 directed to other components to control the operation

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11 1 of the cleaner 10 as will be discussed hereinbelow.

2 The combination of the four amplifiers, 30, 32, 33 3 and 35, respectively, which define the signal 4 processor, may be contained on a single integrated circuit (IC) for ease of manufacturing. One particular 6 IC which has been found to be quite acceptable is a 7 Nationrl Semiconductor LM324 quad op amplifier, 8 althou,h it will be appreciated that other IC's, singly 9 or in combination, as well as individual components thereof, may be used to achieve the same operation for 11 control module 21.

12 The aforesaid output signal from the driver 13 amplifier 35, in addition to, or as an alternative to, 14 energising the indicator light 23, may be interfaced with other components to control the operation of the 16 cleaner 10, as, for example, regulating the speed of 17 "the cleaner motor 26. Specifically, the output signal 18 may be fed to a conventional switching device such as 19 an infrared switch 36, or any other suitable device which preferably permits isolation of the sensor signal 21 from the motor circuit, as would be well known to the 22 skilled artisan. A particular infrared switch 36 which 23 has been found to be acceptable is a Motorola MOC3010 24 opto coupler. The infrared switch 36 is interconnected to a 26 power supply 40 adequate for the cleaner motor 26. A 27 motor controller 41 may be interconnected in series 28 with the infrared switch 36 to control the speed of the 29 motor 26. Specifically, the controller 41 may be any of a number of suitable control circuits known in the 31 art, such as a conventional, low cost, triac control 32 circuit suitable to switch the motor 26 between low 33 speed and high speed operation. Accordingly, when f 1 interconnected with the infrared switch 36, the motor 2 controller 41 will switch the operating speed of the 3 motor 26 in response to the presence or absence of an 4 output signal from the driver amplifier 35 which, as indicated hereinabove, is directly related to the 6 sustained presence of dirt and debris flowing through 7 the air duct 14 of the cleaner 8 The foregoing description may be more fully 9 understood and appreciated by considering the operation of the vacuum cleaner 10. Specifically, the motor 11 controller 41 is able to regulate the power input to 12 the motor 26 to operate normally at approximately 13 percent of full power. It should be appreciated that 14 this low power setting is determined in relation to the nominal power required to allow the cleaner 10 to lift 16 dirt effectively from the surface being cleaned; and 17 that such a setting will vary for different types of 18 cleaners.

19 As dirt is drawn into the unit and discharged through the air duct 14, its presence is detected by 21 the transducer 20. Tests have revealed that the 22 transducer 20 is capable of detecting dirt 23 acoustically, by detecting the sound of the dirt in the 24 airflow; mechanically, by.detecting the vibrations from the impact of the dirt particles against the interior 26 surfaces of thr air duct 14; and electrostatically, by 27 sensing the electrostatic charge created by the 28 movement of the dirt through the air duct 14. In 29 response to the presence of the dirt, the transducer generates an AC signal of approximately 70 to 120 31 millivolts, which has been found to be sufficient to 32 trigger the control module 21.

33 When the signal from the transducer 20 meets or 1 exceeds the aforesaid parameters of three to five 2 pulses within a ten second interval, the control module 3 21 increases the power input to the motor 26 to 4 increase the cleaning effectiveness of the cleaner The motor 26 will continue operating at the 6 elevated power setting as long as dirt and debris in 7 the air duct 14 are sufficient to generate signals 8 within the aforesaid parameters. Then module 21 will 9 maintain the increased power setting of the motor 26 for approximately three seconds following reduction of 11 dirt concentration in the air duct 14, as discussed 12 hereinabove. Following this, the control module 21 13 will switch to the lower power setting for the motor 14 26. The system will remain in this condition until dirt of sufficient concentration again is sensed in the II 16 air duct 14. 17 It has been found that the sensitivity of the 18 system may reasonably be such that the control module 19 21 will trigger at low frequency signals, such as signals in the 2-3 KHz range. However, these signals 21 may be associated with line voltage interference, motor 22 vibrations and the turbulent flow of air through the 23 air duct 14. Typical filters may be employed to 24 eliminate such nuisance signals thereby avoiding false triggering of the module 21. Furthermore, the 26 amplitude sensitivity of the system may be adjusted 27 using the gain adjuster 31, as discussed hereinabove to 28 allow activation of the system at signal amplitudes of 29 approximately 70 millivolts or less. In this manner, the module 21 may be suitably adjusted to trigger only 31 on filtered signals generated by the transducer 20 as a 32 result of dirt of preseiected concentration flowinig 33 through the air duct 14.

Tests have revealed that granular dirt, such as sand, may produce signals having a pulse amplitude of approximately 80 millivolts, with a pulse width of microseconds, which is quite sufficient to trigger the module 21. However, if desired, the sensitivity parameters of the system may be increased to the extent that signals having a pulse amplitude of approximately 24 millivolts, and a pulse width of approximately microseconds, will trigger the module 21. This would generally be sufficient to trigger the module 21 in the presence of fine dirt and dust particles. However, at this sensitivity level adequate signal filtering means, as discussed above, may be necessary to eliminate false triggering of the control module 21 by low frequency signals caused by extraneous sources in the cleaner, as may be known to one skilled in the art.

While the foregoing is a description of one embodiment of the invention, by no means does it constitute the exclusive embodiment. For example, the invention may be incorporated into other types of vacuum cleaners, such as canister cleaners.

Furthermore, the sensor may be positioned at, other locations throughout the dirt path to sense the flow of dirt; and more than one senLor may be employed, or more than one type of sensor, to extend the sensitivity range for sensing dirt. Also, alternative electronics may be employed to process the signal from the sensor to produce a usable output signal. Then, too, means may be provided in the form of a switch, for example, to override or disconnect the system, and allow the cleaner to function in a conventional manner.

It should be appreciated that the preseint invention provides an effective indication of cleaner

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1 operation and/or closed-loop control for the motor 26 2 of the cleaner 10. Such a system allows for highly 3 efficient cleaner operation and efficient utilisation 4 of operator efforts in vacuuming carpets or other surfaces.

6 The overall durability of the cleaner 10 is 7 improved due in part to the fact that the cleaner 10 is 8 operated more often at low power with only intermittent 9 periods of high speed operation. The life of the cleaner motor, bearings, brushes and other components 1 may be increased significantly as a result of the low -h 12 power operation. These critical components can be 13 designed to less demanding standards, resulting in less 14 expensive assemblies. Furthermore, the carpet itself is exposed to less wear because of the generally lower 16 operating speed of the cleaner 17 It should also be appreciated that a cleaner 18 embodying the present invention greatly assists the 19 operator in cleaning. By means of a perceptible indicator, such as a light, and/or change in operation 21 of the cleaner motor, the operator can identify when a 22 dirty area is encountered. The operator can then 23 continue cleaning in the identified area until the 24 cleaner indicates that dirt is no-longer being removed therefrom. Thereafter, the operator may proceed to an 26 area that has not been cleaned without expending undue 27 time. Additionally, with the cleaner generally 28 operating at a lower power level, the operator is less 29 exposed to the noise and vibration generated by the cleaner at higher operating levels, thus reducing the 313 fatigue of the operator.

32 Although the foregoing has considered a cleaner 33 operating normally at. a lower speed, it is likewise 16 1 contemplated for the cleaner normally to operate at a 2 higher speed with intermittent periods of lower speeds.

3 In this fashion, the operator may clean a given area 4 quickly at high speed operation but, when sensor detects dirt, the cleaner may switch to a lower speed 6 so as to avoid damaging internal components of the 7 cleaner by heavy particles of dirt and debris. When 8 such heavy concentration of dirt has been reduced, the 9 cleaner, again, may return to high speed operation. 11 12 13 14 16 17 18 19 21 22 23 24 26 27 28 29 31 32 33

Claims (7)

10. A vacuum cleaner as claimed in any preceding claim 21 in which the sensing means is affixed to the duct means 22 and is physically displaced from the airflow. 23 24 11. A vacuum cleaner as.claimed in any preceding claim in which the sensing means is an acoustical transducer. 26 27 12. A vacuum cleaner as claimed in any preceding claim 28 in which the sensing means is a piezoelectric 29 transducer. 31 13. A vacuum cleaner constructed and arranged to 32 operate substantially as described herein with 33 reference to the accompanying drawings. -19-

14. A method for controlling the operation of a vacuum cleaner having a motor for creating an airflow for transporting particulate matter through an air duct, comprising the steps of: generating a first electrical signal by sensing means responsive to interaction between the duct means and particulate matter in the airflow; processing the first electrical signal; establishing preselected parameters for the first electrical signal; and generating a second electrical signal when the first electrical signal meets the preselected parameters. A method as claimed in claim 14 which includes the step of generating a user identifiable signal in response to the second electrical signal.

16. A method as claimed in claim 15 in which the user identifiable signal is provided by an indicator lamp.

17. A method as claimed in claim 14 or claim 15 or claim 16 which includes the step i' i of regulating the airflow through the air duct in response to the second electrical signal. 20 18. A method as claimed in claim 17 in which the step of regulating the airflow includes controlling the operation of the motor. t 1 i.

19. A method as claimed in any of claims 14 to 18 in which the step of generating a first electrical signal includes affixing a transducer to the air duct at a location physically displaced from the airflow, and exciting the transducer by passing particulate natter through the air duct.

20. A method as claimed in any of claims 14 to 19 which includes the step of maintaining generation of the second electrical signal for a preselected period of time following termination of the first electrical signal to meet preselected parameters. S930513pope 482319 t t S 930513,p:,opcrgcp,45823Al19 i c.- 20

21. A method of controlling the operation of a vacuum cleaner substantially as described herein with reference to the accompanying drawings. DATED this 13th day of May, 1993 HOOVER PLC By its Patent Attorneys DAVIES COLLISON CAVE 4, I I IC C .54 I 4,44 I S *5 S I 5* S S 5 lIt I 93O513,p:\opcr~cp,45B23.c,2