GB1598372A - Electronically-actuated valve for intermittently discharging a pressurised aerosol container - Google Patents

Description

(54) ELECTRICALLY-ACTUATED VALVE FOR INTERMITTENTLY DISCHARGING A PRESSURISED AEROSOL CONTAINER (71) I, FERNANDO GALLEGO FOJON, a Citizen of Spain, of Purisima, 18 4Burriana, Castellon, Spain, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to an apparatus for automatically discharging the contents of an aerosol container, and is intended in particular for use in bathrooms and washrooms, or in any room, building, or other place where the automatic atomisation of disinfectants, air-fresheners or perfume sprays is required.

According to this invention, an electronically actuated valve for intermittently discharging a pressurised aerosol container comprises a body having a socket for receiving a conventional pressurised aerosol container and for maintaining the valve of the container in an open condition, a nozzle for atomising and discharging the contents of the container, the socket and the nozzle being connected through a valve including a displaceable valve member biassed towards the closure position and rigid with a soft iron member which is associated with an electromagnet so that when the electromagnet is energised it attracts the soft iron member, overcomes the biassing, and opens the valve. This arrangement has the advantage that mechanical action on the valve of the aerosol, action which would require considerable mechanical force, is not necessary. The apparatus in its preferred form is battery powered and relativey easy to handle. It may provide an extensive range of spray programmes from a hour to one hour and regulation of the shot (quantity of liquid discharged in each shot).

The size of the shot is determined automatically, as the valve of the aerosol is coupled to an electromagnetic valve the activation or opening of which brings about the discharge of the liquid from the aerosol through a spray nozzle, this opening being achieved electronically in the preferred embodiment as is described below: An electromagnetic valve and a nozzle comprise a plastic support on the inside of which is housed a valve core which is fixed to the actual plastic block or support. On the lower part of this assembly there is a means which is joined by a watertight seal to the nozzle or valve of the aerosol. When this acts upon the nozzle, the pressure and the liquid passes from it to a cavity formed by the valve; this cavity is made of brass and comprises a hollow cylinder at the end of which is an orifice plugged by a hollow piston completed by a plug of rubber or similar elastic material which remains pressing upon the orifice; the other end of the said piston is joined to a cylindrical piece of wrought iron, this being highly magnetic, and adjacent to it and at a distance controlled by a rubber joint and a sheet of brass rendering the whole thing watertight is an electromagnet. The electromagnet is made up of a core upon which is wound a coil of enamelled copper wire, which core, when a current is passed through it becomes temporarily magnetised, attracting the cylinder of iron fixed to the valve piston, then opening the orifice and causing discharge of the liquid. In order to increase the magnetic field on the cylinder, the whole thing, core and coil, is enclosed in a cylindrical casing of iron which concentrates the magnetic field on the cylinder. To ensure that when the electromagnet is not activated the valve is closed, there is a spring which exerts a force which prevents the escape of liquid from the aerosol. At the exit of the orifice of the valve is found a channel at the end of which is a cap of a different material in which there is smaller orifice to atomize or pulverise the liquid coming from the aerosol as it leaves the apparatus.

The support of the aerosol is of characteristic shape so that at the same time as serving as its support, it fulfills the role of adaptor; the nozzle of the aerosol by its design serving at the same time as a housing for the batteries which provide the energy for the assembly.

In order to obtain automatic dosing of the discharge from the valve of the aerosol, there is incorporated an electronic system applicable to the apparatus and to the spraying mechanism, there being created a totally compact electronic device as used in the most modern circuits, of the type CMOS, which are characterized by their reduced power consumption, and excellent reliability. At the same time the size of the apparatus is reduced since the said electronic assembly can be mounted on a printed circuit board of reduced dimensions.

In general terms the electronic circuit incorporated in the atomising apparatus which concerns us comprises an impulse generator, an impulse divider and a monostable circuit.

A timer, has the job of measuring the length of time for a particular purpose, in our case for actuating an electrovalve or electromagnet. Thus any timing is based on a sum of times or impulses, the sum of these impulses giving a final time, and this task of generating these positive rectangular impulses being controlled by a circuit formed by three inverters in an oscillator assembly which oscillate as a function of a supply network formed by the series arrangement of a capacitance and a variable resistance; a fourth inverter inverts and amplifies the signal. In any time-measuring system the stability and accuracy of it is determined by the frequency, thus at higher frequencies, the accuracy is greater; in our case accuracy is not essential, but to obtain an impulse every fifteen minutes in order to activate the valve would be very difficult, since the aforementioned capacitor would have to have a very high capacitance and the potentiometer a very high resistance, for this reason the frequency of the oscillator has been divided by a binary counter whose job, as its name implies, is to count the impulses obtained at its various outputs, the values as a function of the number of impulses received at the input of the same, that is to say the integrated counting circuit has an input and various outputs and internally it counts the input impulses in binary form and each output corresponds to a sum in the binary. When, for example, 32 impulses are received at the input, one of the outputs is activated, and when the number of impulses reaches 512 another output is activated, and so on, so that this second output for example remains at the level 0 until impulse No. 512 is received at the input; thus a division has been produced since the 512 impulses of the oscillator have been transformed into 1 impulse at the selected output of the divider, thus if the frequency of the oscillator is set at 1 impulse per 2 seconds we have 512 x 2 equal to 1,024/60 which corresponds to 17 minutes, that is to say after every seventeen minutes we shall obtain an output impulse, or if for example we select a frequency of 1 impulse per 30 seconds then we shall have 512 x 30 which corresponds to 15360/60 which is equal to 256 minutes/60 corresponding to 4.27 hours so that we shall obtain an impulse at the selected output at the end of 4.27 hours, or that in the various outputs there are obtained different total values as a function of the input (impulses received), thus we can choose a fixed frequency for the oscillator, for example one impulse per 8 seconds, at the various outputs, passing from the value 0 to 1 successively as a function of the binary total of the input impulses, the following values being obtained: 128 x 8 = 1024 secs./60 = 17 min. = 1/4 h.

256 x 8 = 2048 secs./60 = 34 min. = 1/2 h.

512 x 8 = 4096 secs./60 ~ min. = lh.

1,024 x 8 = 8192 secs./60 = 136 min. = 2.28 h.

2,048 x 8 = 16,384 secs./60 = 273 min. = 4.55 h.

Then for a fixed frequency of the oscillator and by means of switches which select one of the various outputs we obtain the impulse corresponding to its binary division and consequently a range of different timings.

A study of the adaption of this circuit to its task, which is to fire a spray at a particular time makes one think more of a minimum time from shot to shot with an interval of approximately 15 minutes and an indeterminate maximum, this being up to the user, but which could be 4 hours for real effectiveness of the product contained in the spray. Thus we have 1/4 hour - 15 minutes minimum and 4 hours - 240 minutes maximum; that is to say that by varying the frequency of the oscillator from 2 seconds to 30 seconds there is obtained a progammed time from 15 minutes to 4 hours with intermediate intervals controllable at l/2 hour, 1 hour, I l/4 hours, and so on up to 4 hours simply by means of varying the position of a slide of a potentiometer.

Once the timed impulse which we shall call the control has been obtained. we apply this impulse to a monostable circuit, so called because it passes from a state of 0 to 1 on receiving an impulse at its input, there being obtained at its output an oscillating impulse from 0 to 1 and again from 1 to 0, controlled by a second capacitor and another variable potentiometer there being obtained different oscillation times in the output of the monostable circuit which constitutes an electronic dosing means for the measuring of the quantity of the product in each shot.

We apply the impulse thus obtained to an output circuit capable of controlling the valve; this circuit is formed by two transistors in a Darlington-like assembly, so that the output signal of the monostable circuit is applied across a resistance, at the base of a first transistor, the collector of which is joined to the positive terminal of the battery and the emitter of which drives the base of a second, power transistor, the emitter and collector of which are respectively connected to the negative terminal of the battery and to the positive terminal of the battery via the electromagnet coil.

It is important to point out that in this type of arrangement of the circuit, power consumption is relatively low, and thus the working life of the batteries is relatively long, this factor being very important since the inconvenience of changing the batteries frequently is eliminated; a study of consumption in relation to the frequency of the oscillator gives the following figures in the quiescent state (electromagnet inactive): Continuous current for 1 impulse per 2 seconds = 325 to 400 ijA giving an average of 365 I.LA.

Continuous current for 1 impulse per 30 seconds = 200 to 3001lA giving an average of 250 A.

Continuous current with the electromagnet activated is 350 mA.

The invention will now be described by way of example with reference to the drawings in which Figure 1 is a front elevation of an aerosol container housing, cut away to show compartments for housing batteries; Figure 2 is a longitudinal section taken on the line A-B in Figure 1 showing the cavities for the batteries and the means for holding the aerosol container in the apparatus; Figure 3 is a front view of the body of a valve for atuomatic discharge, showing the surface to which an electronically activated electromagnet is attached; Figure 4 is a side elevation of the body of the valve of Figure 3 showing below the connecting nozzle of the aerosol and at the side the programmed discharge nozzle, opposite the surface on which the electromagnet is to be mounted; Figure 5 is an underneath view of the body of the valve showing the orifice for communication with the aerosol container; Figure 6 is a top plan of the body of the valve Figure 7 is a rear elevation of the body of the valve through the part which faces the exterior of the apparatus, there being visible in the centre an orifice in which is housed the discharge nozzle for the atomisation of liquid; Figure 8 is an enlarged longitudinal section of the body of the valve and the electromagnet; Figure 9 is a side view of an elastic seal between the body of the valve and the electromagnet; Figure 10 is a side view of a non-magnetic metallic plate which allows the passage of the magnetic flux and acts as a metallic membrane between the body of the valve and the electromagnet; Figure 11 is a diagram of an electronic control circuit, including CMOS integrated circuits indicated by dotted lines; Figure 12 is a diagram of an alternative electronic control circuit, differing from that of Figure 11 in that at the output of the binary counter there is a series of contacts operable from the exterior by a set of buttons for setting preset time intervals between two consecutive discharges; Figure 13 is a front view of electronic atomising apparatus in accordance with the invention showing the location of the nozzle for the atmosiation of the contents of the aerosol; an electronic control circuit board; a control for programming the timing of the discharges; an atomisation duration control; a push button for ascertaining the state of charge of the batteries and a main switch; Figure 14 is a front view of an alternative layout of the apparatus, the circuit board being mounted in a space between the batteries, situated below the nozzle and a pair of rotatable potentiometers; Figure 15 is a front view of a further alternative apparatus, including a set of buttons, which are operable such that when one of these buttons is pressed and remains depressed it acts upon the circuit, producing atomisation at regular intervals according to the time interval programmed by the depressed button; and Figure 16 is a front view of yet a further alternative apparatus with a simplified set of buttons permitting only three different time settings for the time interval between two consecutive discharges.

Referring to the drawings, the reference numbers have been allocated as follows.

The casing which contains all the mechanisms and apparatus which constitute the electronic atomising apparatus of the invention is marked -1-, there being included in this the housing -2- for the aerosol container -3-, and in its base the housings -4- for the batteries -5- which energise the electronic circuit.

In the lower part of the housing -2- which houses the aerosol there is a sloping wall -6through which is permitted the correct positioning of the aerosol container until it rests supported on the internal wall -7-, its valve having been introduced into the body -8- for automatic discharge in the case of the position shown in Figure 2, being introduced according to the direction of the arrows -9-, i.e. sloping upwards until the correct supported position is achieved.

The aerosol container -3- is introduced by its valve into the mouth -10- of the valve body -8-, being joined by an air-tight seal to the cap -11- of elastic material, the valve of the aerosol remaining open and the liquid under pressure, inside the channels -12- in the inside of the valve body -8-, the electro-magnet -13- being joined to the surface -14- of the body of the valve -8- and the said magnet being covered by a bell-housing or cover -15- which strengthens its magnetic field. In order to obtain a watertight or hermetic seal between the housing or cover -15-, which encloses the electrovalve, with the valve body -8- there is used a sealing member -16- of elastic material provided with orifices -17- for assembly and a central orifice -18- and also with another sealing member -19- of thin metallic sheet (e.g. of brass) assembled with the orifice -20-, which acts as a membrane and allows the magnetic field produced by the electromagnet -103- to act on a cylindrical member -21- of soft iron which is very sensitive to magnetism, so that when the electromagnet -13- is activated the soft-iron member -21- is attracted downwards, overcoming the resistance of the spring -22-, and as this member -21- is rigid with the cylinder -23- it pulls the latter with it, opening the orifice -24- which was previously closed by the rubber stopper -25-. In this way the liquid under pressure contained in the channels -12- is allowed to pass through the channel -26- to the nozzle -27-, where it is atomised and discharged through orifice -28-.

The valve body -8-, made of shock resistant plastics, is fitted into the case -1- by means of screws -21- fixed into the holes -30-. Webs -31- give the whole assembly mechanical strength and solidity.

In the interior of the container -1- is a board -32- mounting electronic circuit compoents, including an integrated circuit -33- which acts as an oscillator, and has a group of input inverters -34- and an output inverter -35- which amplfies and inverts the signal. This oscillator -33- acts in response to a dose frequency control 36 operable by the user. A capacitor -37-, a potentiometer -38- and a resistor -31- are connected in series with the control -36-. The output of the oscillator -33- is connected to an integrated circuit -40- which comprises a binary counter provided with various outputs. This counts the input impulses in binary form and each output corresponds to a certain total of input impulses, each output passing to the monostable integrated circuit -41-, the resistor 42 biasing the other input positive.

The monostable circuit-41- is connected to a dose size control -43- operable by the user for controlling the duration of each discharge of the aerosol (time of valve opening).

The output of the monostable integrated circuit -41- is connected via a resistor -46- to the base of a transistor -47-. The transistor base is also connectable to the positive rail by a resistor -48- and a push-button -49-, which may be used to check the level of charge of the battery -5-. The emitter of the transistor -47- is connected to be base of a transistor -50-, forming a power amplifier circuit of a Darlington-like type, the collector of the transistor -47- being connected to the positive rail and the collector of the transistor -50- itself being connected to positive rail via the coil -51- of the electromagnet -13-. The main switch -52for stopping or starting the apparatus is connected between the battery 5 and the positive rail.

In Figure 14 the dose frequency control -36- and the dose size control -43'- are rotatable, simplifying assembly and saving considerable space.

In an alternative embodiment of electronic control circuit the dose size potentionmeter -36- of Figures 11 and 14 may be replaced by the set of push switches -53- provided with contacts -54- connected to the outputs of the binary counter in the package 40. In this embodiment, the oscillator -33- operates with a fixed frequency and each push-switch -53selects an output corresponding to a different number of oscillation pulses. In this way five or three different dose frequency settings may be selected, as indicated by the arrangement of the push switches -53- or -55- in Figures 15 and 16 respectively. In Figure 16, three dose interval settings are available: , 1/2 and 1 hour.

Claims (8)

WHAT I CLAIM IS:

1. An electronically actuated valve for intermittently discharging a pressurised aerosol container, comprising a body having a socket for receiving a conventional pressurised aerosol container and for maintaining the valve of the container in an open condition, a nozzle for atomizing and discharging the contents of the container, the socket and the nozzle being connected through a valve including a displaceable valve member biassed towards the closed position and rigid with a soft iron member which is associated with an electromagnet so that when the electromagnet is energised it attracts the soft iron member, overcomes the biassing, and opens the valve.

2. An electronically actuated valve according to claim 1, wherein the electromagnet and the soft iron member are isolated from one another by a seal of non-magnetic material.

3. An electronically actuated valve according to claim 1 or claim 2, wherein the electromagnet is energised by an electronic circuit including an oscillator and a pulse counter for determining the interval between successive discharges from the container.

4. An electronically actuated valve according to claim 3, wherein the oscillator frequency is adjustable to vary the said interval.

5. An electronically actuated valve according to claim 3 including means for selecting different counter outputs so as to vary the said interval, the oscillator frequency being fixed.

6. An electronically actuated valve according to any of claims 3 to 5 wherein the counter is connected to a monostable circuit with a dose size control for controlling the duration of the discharge.

7. An electronically actuated valve according to any of claims 3 to 6 wherein the oscillator comprises an integrated circuit including a group of inverter elements coupled to a series arrangement of a resistance and a capacitance.

8. An electronically actuated valve constructed and arranged substantially as herein described and shown in the accompanying drawings.