Classifications

• • A—HUMAN NECESSITIES
  • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
  • A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
  • A47L9/00—Details or accessories of suction cleaners, e.g. mechanical means for controlling the suction or for effecting pulsating action; Storing devices specially adapted to suction cleaners or parts thereof; Carrying-vehicles specially adapted for suction cleaners
  • A47L9/28—Installation of the electric equipment, e.g. adaptation or attachment to the suction cleaner; Controlling suction cleaners by electric means
  • A47L9/2857—User input or output elements for control, e.g. buttons, switches or displays
• • A—HUMAN NECESSITIES
  • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
  • A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
  • A47L9/00—Details or accessories of suction cleaners, e.g. mechanical means for controlling the suction or for effecting pulsating action; Storing devices specially adapted to suction cleaners or parts thereof; Carrying-vehicles specially adapted for suction cleaners
  • A47L9/28—Installation of the electric equipment, e.g. adaptation or attachment to the suction cleaner; Controlling suction cleaners by electric means
  • A47L9/2805—Parameters or conditions being sensed
• • A—HUMAN NECESSITIES
  • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
  • A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
  • A47L9/00—Details or accessories of suction cleaners, e.g. mechanical means for controlling the suction or for effecting pulsating action; Storing devices specially adapted to suction cleaners or parts thereof; Carrying-vehicles specially adapted for suction cleaners
  • A47L9/28—Installation of the electric equipment, e.g. adaptation or attachment to the suction cleaner; Controlling suction cleaners by electric means
  • A47L9/2805—Parameters or conditions being sensed
  • A47L9/2831—Motor parameters, e.g. motor load or speed
• • A—HUMAN NECESSITIES
  • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
  • A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
  • A47L9/00—Details or accessories of suction cleaners, e.g. mechanical means for controlling the suction or for effecting pulsating action; Storing devices specially adapted to suction cleaners or parts thereof; Carrying-vehicles specially adapted for suction cleaners
  • A47L9/28—Installation of the electric equipment, e.g. adaptation or attachment to the suction cleaner; Controlling suction cleaners by electric means
  • A47L9/2836—Installation of the electric equipment, e.g. adaptation or attachment to the suction cleaner; Controlling suction cleaners by electric means characterised by the parts which are controlled
  • A47L9/2842—Suction motors or blowers

Definitions

• the present invention relates to an arrangement for a vacuum cleaner of the kind indicated in the preamble of the appending claim 1.
• the coil and capacitor of the primary circuit is supplied by an oscillator of a frequency coinciding with the resonant frequency of the circuit, maximizing the current in said circuit.
• a load is connected which comprises a number of resistors, corresponding to different operating modes, each of which being connected in series with a manually operable contact.
• a selected contact brings the desired resistor to be connected in parallel to a series circuit formed by a secondary coil and a capacitor.
• the primary resonant circuit can be loaded to various degrees, causing the voltage across the primary c j.euit capacitor to take different identifiable levels.
• the number of levels is limited by the fact that said levels have to be identifiable in a safe way.
• the object of the invention is to eliminate the limitation as to the number of levels in a vacuum cleaner of the kind referred to and to provide an arrange ⁇ ment permitting the transfer of information from a manual control device dis ⁇ posed on the hose-mounted handle and concerning an * arbitrary number of operating modes.
• T e object is achieved by an arrangement which has the characterizing features indicated in claim 1. Preferred embodiments have been included in the accompanying sub-claims.
• FIG. 1 schematically shows a vacuum cleaner having a hose and a dust collecting nozzle connected to it;
• Fig. 2 is a schematic view of the interior of the vacuum cleaner
• Fig. 3 is a block diagram of a control device for the vacuum cleaner motor, said device being operated from a hose -mounted handle
• Fig. 4 is a timing diagram showing voltages and waveforms appearing in the control device of Fig. 3;
• Fig. 5 is a block diagram of a modification of the control device of Fig. 3;
• Fig. 6 is a timing diagram for voltages and waveforms appearing in the circuit shown in Fig. 5;
• Fig. 7 is a circuit diagram for a practical embodiment of the secondary circuit
• FIG. 8 is a timing diagram of voltage waveforms appearing in the circuit of Fig. 7.
• Fig. 1 shows a vacuum cleaner 10 of common design. Via a hose 11, having a hose handle 12 and an extension tube 13, the cleaner is connected to a dust collecting nozzle 14. As shown in Fig. 2, the vacuum cleaner is provided with an inlet opening 15 and an outlet opening 16. By a suction fan 17, driven by an electric motor 18, an air stream is established between said inlet and outlet openings. The air stream passes a dust container 19 in which dust, conveyed with the air stream, is kept.
• An electronic control device 20 is provided in the vacuum cleaner to make possible operation at various speeds. The control device can be operated by an operating member 21, disposed on the hose handle 12 and being, for instance, a slide switch which can be set into four different positions closing four different contacts, as will be described more in detail below.
• the operating member 21 is part of an operating device 22, shown in Fig. 3. By sliding of the operating member the desired contact can be closed.
• the operating device is interconnected with a logic arrangement 23 which co-operates with a contact 24 being, in series with a capacitor, connected in parallel with the secondary coil 26 of an air transformer 27.
• the primary coil 28 of the transformer is connected in series with a capacitor 29 forming therewith a series resonant circuit 30 supplied form an oscillator 31.
• the primary coil is disposed in the vacuum cleaner and the secondary coil is disposed in the hose at the end connecting to the vacuum cleaner, indicated in Fig. 1 by arrow 32.
• the connecting point between the coil 28 and the capaci ⁇ tor 29 is connected to a level detector 34, the function of which will be described below.
• the level detector Via a conductor 35, the level detector is connected to a counter 36 which is also, via a conductor 37, connected to the conductor 33.
• the counter is con- nected to a decoder 38 which in turn is connected to the control device 20 for the motor 18.
• the oscillator 31 feeds the series resonant circuit, comprising the primary coil 28 and the capacitor 29, at a frequency maximizing the current in said circuit.
• a voltage is induced in the secondary coil 26, said voltage being used also for powering of the logic arrangement 23.
• a smoothed DC voltage is generated by a diode 39 and a smoothing capacitor 40.
• the level detector 34 Upon the decrease of the capacitor voltage U c the level detector 34 is again activated operating the counter to start counting. When, after the period T j , the level is again increasing, the level detectof is again activated stopping the counter. The count corresponds to the- time Ti -and is decoded in the decoder 38 emitting an output voltage depending on the count and thereby indicating the closing of contact 22a. *. '
• the closing of the contact 22b is indicated by the logic arrangement 23 keeping the contact 24 closed during a longer time * T£ » for instance amounting to 2 x Tj.
• the counter 36 has time to count twice as many pulses as in the first-mentioned case and the corresponding output voltage from the decoder 38 will be correspondingly higher.
• FIG. 5 An alternative embodiment is shown in Fig. 5 and is being described also with reference to Fig. 6.
• the circuit is the same as in Fig. 3, however, differing in that, via a conductor 41, the oscillator has a feed- back - o * op from the con ⁇ necting point between the primary coil 28 and the capacitor 29. This feed-back causes the frequency of the oscillator to depend on the condition in the seconda ⁇ ry circuit.
• the voltage U c across the capacitoir 129'i has been given a mainly constant amplitude. This is not completely corredt but has been done to indicate that here the frequency of the oscillator is of interest and not the voltage level. Said frequency can take two different values determined by the condition of the secondary circuit.
• a frequency change detector 42 replaces the level detector 34 in Fig. 3. As appears from the middle diagram in Fig. 6, detector 42 indicates when the frequency changes from a lower to a higher value, thereby emitting a pulse starting the counter 36. The counter counts the pulses appearing on the conductor 37 and the counting continues until the detector 42 indicates that the frequency again changes to the lower value. This change corresponds to a change in the condition of the secondary circuit caused by the opening of contact 24.
• the detector 42 determines a first time T- cor ⁇ responding to the closing of the contact 22a.
• the frequency is higher than during the time of operation of the cou ter and, therefore, the number of pulses for each contact is higher than in the embodiment of Fig. 3, resulting in an improved distinguishing capability of the conversion device.
• the closure of the contact 22b causes the counter to be activated during the time T4 which is twice as long as T3. The number of counted pulses will increase correspondingly.
• Fig. 7 a practical design of the secondary circuit is shown.
• the electronic components mounted in this circuit are powered from the oscillator 31 of the primary circuit. If it is of interest to detect level, as in the embodiment of Fig. 3, this means that during periods of low level, when the counter 36 is to operate, the oscillator is heavily loaded which cannot continue during any longer time if the oscillator is to operate safely.
• the circuit shown in Fig. 6 remedies this drawback by ensuring that during periods of activated counter the secondary circuit does not load the oscillator, i.e. the voltage U c across the capacitor 29 (Fig. 3) has a high level.
• the logic arrangement is constituted by a counter 45 co-operating with a flip-flop 46.
• the contact 24 of Fig. 3 here takes tha shape of a transistor switch 47 for AC, compare TRIAC, connected in series with a capacitor 25 (the same reference numeral as in Fig. 3).
• the counter 45 being of the type 4040, receives clock pulses which are derived from the oscillator voltage and which are led, via a capacitor 48, to the clock pulse input CP.
• the counter has an output Q4, a RESET input R and a number of outputs connected to an operating device 49 equipped with contacts.
• the principle of this circuit is that the oscillator be loaded during short periods of time only as compared to the total time during which the detection of the setting of the operating device 49 takes place. In this way, it is ensured that the oscillator of the primary circuit is not unneccessarily disturbed while at the same time the supply voltage of the secondary circuit is maintained, causing the electronic components of this circuit to operate in a faultless manner.
• the counter 45 permanently receives clock pulses on the input CP. Now, when a contact in the operating device 49 is actuated, via an OR-gate 50 and an inverter 51 a high level is created on the RESET- input R of the counter which is being reset and then starts to count-up.
• the high level on the output of the inverter 51 is also led to the SET-input S of the flip-flop 46 setting the flip-flop, which causes the transistor switch 47 to close connecting the capacitor 25 in parallel with the secondary coil 26.
• a diagram is shown of the capacitor voltage U c (Fig. 3) and the low level corresponds to the condition of the secondary circuit, just described.
• the output Q4 of counter 45 is activated causing a high level to be applied to a RESET-input R of flip-flop 46.
• the flip-flop is resetted causing the transistor switch 47 to open and to disconnect the capa ⁇ citor 25.
• the voltage U c rises to the high level at which it remains during the continued counting-up of the counter to, in proper order, activate the outputs Q6 - Q9, connected to the operating device 49, in order to detect the closing of any contact.
• the first time TOl corresponds to a first contact being closed.
• the time TOl corresponds to the time from the activation of the output Q4 and to the activation of the output corresponding to said first contact.
• the counter 45 is resetted in the way described via the gate 50 and the inverter 51.' Then, the counter restarts with a period of low level until again the output Q4 has been activated.
• Fig. 8 the first time TOl corresponds to a first contact being closed.
• the time TOl corresponds to the time from the activation of the output Q4 and to the activation of the output corresponding to said first contact.
• the closing of a second contact in the operating device corresponds to the time T02, twice as long as the time TOl, while a third contact corresponds to the time T03 which is twice the time T02.
• the times TOl, T02, T03 etc. are thus separated by the time TOO representing periods of the same duration and of low level.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Electric Vacuum Cleaner (AREA)
• Electronic Switches (AREA)
• Control Of Ac Motors In General (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20375046

Family Applications (1)

Country Status (6)

Cited By (2)

Families Citing this family (4)

Citations (5)

• 1989
  • 1989-02-14 SE SE8900504A patent/SE463071B/sv not_active IP Right Cessation
• 1990
  • 1990-01-24 WO PCT/SE1990/000050 patent/WO1990009139A1/en active IP Right Grant
  • 1990-01-24 EP EP90903242A patent/EP0409959B1/en not_active Expired - Lifetime
  • 1990-01-24 JP JP2503380A patent/JPH03503973A/ja active Pending
  • 1990-01-24 US US07/582,947 patent/US5081738A/en not_active Expired - Fee Related
  • 1990-01-24 CA CA002027551A patent/CA2027551A1/en not_active Abandoned

Patent Citations (5)

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