DESC:FIELD OF INVENTION:
The present invention relates to a system and device for vaporization of liquid and more particularly to a system and a device which enable quick release of liquid at the onset and subsequently provide differential release of the liquid at predetermined time intervals in a cyclic manner.

BACKGROUND AND PRIOR ART:
Devices and methods for the release of liquids into the air have been in use for decades. These devices are usually used as air fresheners or for dispensing insect repellents or fragrances.

US Patent No. 4915301, US Patent No. 6109539, and US Patent No. 4419326 disclose different devices for releasing insect repellents and fragrances into the air. However, these devices do not achieve quick release of the liquid at the onset.

EP1549139B1 discloses a wick based delivery system for transporting liquids, such as fragrances or insecticides from a reservoir to a surface exposed to ambient air, wherein the device includes a container for holding a liquid, and a two-section wick for transporting the liquid from the container to an upper surface of the wick, with wick having sections of varying porosities. The device disclosed therein claims to exhibit an initial spike in the release rate of the vaporizable liquid when the device is first activated, due to the two-section wick (3) having varying porosities. However, the use of a dual pore size wick makes the manufacturing of the wick cumbersome. It also increases manufacturing time and adds to the cost of the product.

One of the major drawbacks with the devices that are available in the prior art is that when the devices are switched on or activated, there is a lag time between the initiation of the device and release of sufficient liquid into the surrounding environment, often having an effect only after an initial delay, or having a subsequent sub-optimum release of the desired liquid. In so far as the device disclosed in EP1549139B1 is concerned, although it claims to have instant release of the liquid once the device is switched on, the dual porosity wick required to achieve the desired goal makes the device expensive and complicated to manufacture.

Yet another drawback is that most of the available systems and devices operate in a single mode. Even the ones that do offer differential release of the liquid, do not offer cyclic operations. This does not give the flexibility for offering differential release from the same system or device at timely intervals.

A drawback of the wicks of the prior art is that they are unable to withstand temperatures above 160-170°C. This limits the amount of liquid that may be released into the air which would otherwise have been higher at a temperature above 170°C.

There is, therefore, a need for a system and a device which address each of the aforesaid drawbacks of the prior art. In view thereof, what is required is a system and a device which are able to achieve a quick release of the liquid into the air at the onset and which subsequently maintain a steady supply of the liquid into the air in flash and normal modes at regular intervals. The device should be cost effective, easy to manufacture and not bulky. Further, a wick which is suitable for such system and device is also required.

In addition, it is desirable to have a system and a device for differential release of the liquid, which uses a device to control and allow varied voltage supply between the thermistors.

OBJECT OF THE INVENTION:
It is an object of the present invention to provide a system and device which provide quick release of the liquid into the air at the onset and to all corners of the room, when switched on, without an initial lag or delay.

It is another object of the present invention to provide a system and device for differential release of liquid into the surrounding environment in a cyclic manner at predetermined time intervals, while maintaining continuous and adequate supply of active ingredients from the liquid into the air to all corners of the room.

It is yet another object of the present invention to provide a system and a device which have a timer controlled mode and which work on direct household electric sockets and give differential release patterns, offering instant knock down and longer repellency to insects based on the time interval program induced in the timer based device.

It is yet another object of this invention to provide a wick which is thermostable at a temperature of up to 220°C and is suitable for use in the system and device of the present invention.

SUMMARY OF THE INVENTION:
The present invention relates to a system for vaporization of a liquid inter alia comprising,

a liquid stored in a container having a wick whose one end is immersed in the said liquid and the other end is protruding from the container,

a system to heat the end of the wick protruding from the container,

characterized by the fact that the wick is of high porosity, is thermostable at 220°C and is made of nylon and one or more polyester, poly phenylene sulphide, poly ether sulphone or combination thereof; and

there is provided a device to control and vary the temperature of the heating surface of the heating assembly.

The present invention also relates to a device for vaporization of a liquid inter alia comprising of a hollow container with a closed bottom and an opening at the top, holding a liquid, a wick whose one end is immersed in the said liquid and the other end is protruding from the top opening of the container, a heating assembly whose heating surface is in close proximity to the other end of the wick characterized by the fact that the wick is made of nylon and one or more polyester, poly phenylene sulphide, poly ether sulphone or combination thereof such that it has high porosity and is thermostable at temperature of 220°C; and a device to control the PTC Thermistor (high temperature) is connected to the heating assembly to control and vary its temperature.

The present invention also relates to a device as described above, wherein the wick consists of 80% nylon and 20% polyester or poly phenylene sulphide or poly ether sulphone material or combination thereof.

The present invention also relates to a device as described above, wherein the wick consists of 80% nylon and 20% polyester.

The present invention also relates to a device as described above, wherein the wick has a porosity of up to 85%.

The present invention also relates to a device as described above, wherein the temperature of the heating surface of the heating assembly alternates between a temperature in the range of 170-220°C and a temperature in the range of 140-160°C for a predetermined time, in a cyclic manner.

The present invention also relates to a device as described above, wherein the temperature of the heating surface of the heating assembly is maintained at a temperature in the range of 170-220°C for 30 minutes and at a temperature in the range of 140-160°C for 210 minutes.

The present invention also relates to a device as described above, wherein the temperature of the heating surface of the heating assembly initially attains a temperature in the range of 170-220°C for a predetermined time and subsequently drops down to but is constantly maintained at a temperature in the range of 140-160°C.

The present invention also relates to a wick for use in a system and a device for vaporization of liquid characterized by the fact that the wick is made of nylon and one or more of a polyester or poly phenylene sulphide or poly ether sulphone material or combination thereof.

The present invention also relates to a wick as described above, wherein the wick is made of 80% nylon and 20% polyester or poly phenylene sulphide or poly ether sulphone material or combination thereof.

The present invention also relates to a wick as described above, wherein the wick is made of 80% nylon and 20% polyester.

The present invention also relates to a wick as described above, wherein the porosity of the wick is up to 85%.

BRIEF DESCRIPTION OF THE DRAWINGS:

The following drawings are illustrative of particular examples for enabling the working of the system and device of the present invention. They are descriptive of the invention and are not intended to limit the scope of the invention. The drawings are not to scale (unless so stated) and are intended for use in conjunction with the explanations in the following detailed description.

In the accompanying drawings:
Fig.1 shows an exploded view of the system and device for vaporization of liquid
Fig.2 shows a circuit diagram of the PCB and the different electrical components of the system and device

It will be understood that certain elements may be intentionally omitted from a particular view where they are believed to be illustrated for better advantage in the other view.

The following are the details of the main components of the system and device for vaporization of liquid in accordance with the present invention which are used with reference to Figs. 1 and 2.

1 = Front cover
2 = Switch
3 = PCB
4 = Top cover of heating assembly
5 = Heating assembly
6 = Bottom cover of heating assembly
7 = Holder
8 = Wick
9 = Plug
10 = Container
11 = Vent
12 = Back cover
13 = Screws
14 = Pin bridge
15 = U-terminal
16 = PTC Thermistor (low temperature)
17, 18 = I- terminals
19 = PTC Thermistor (high temperature)
20 = Capacitor
21 = LED
22 = Diode rectifier
23 = Device for controlling PTC Thermistor (high temperature)
24 = Thyristor

Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure. Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures. However, the drawings and/or illustrations in no way limit the scope of the invention. It is understood that modifications and/or alterations of the drawings/illustrations of this invention other than those specifically set forth herein may be achieved by those skilled in the art and that such modifications and alterations are to be considered as falling within the overall scope of this invention.

DETAILED DESCRIPTION OF THE INVENTION:

The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the system and device according to the present invention (hereinafter for the sake of brevity the system and device are collectively referred to as “the device”) as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventors to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

Figure 1 shows an exploded view of the device for vaporization of liquid. The device comprises of a front cover (1) and a back cover (12), which form the outer shell of the device. A switch (2) protrudes from the front cover (1), which may be used by the user to switch from flash mode to normal mode and vice versa. The device is provided with a printed circuit board (PCB) (3), which is housed behind the front cover (1). The PCB (3) supports and electrically connects the electrical components of the device. The device is further provided with a container (10) which holds the liquid to be vaporized. The container (10) is preferably a transparent plastic container. However, the container may be made of any suitable material for holding liquids. A holder (7) is provided to hold the container (10) in place. In a preferable embodiment of the present invention, the liquid comprises of a solvent, antioxidants, and volatile materials which may be selected from one or more of an insecticide, air care materials, perfumes, odorants, essential oils or malodour chemicals among other such materials. In another preferable embodiment of the present invention, the liquid is an aliphatic hydrocarbon solvent.

The different parts of the device are held together by means of screws (13). A vent (11) is provided for release of the vapour into the air. The pin bridge (14) holds the pins together for insertion in a pin socket.

The device further comprises of a wick (8). The lower portion of the wick (8) is in direct contact with the liquid inside the container (10), whereas the upper portion of the wick (8) protrudes from the container and is exposed to the air. The container (10) is provided with a plug (9) which is fitted tightly into the neck closure of the container (10) to prevent any leakage from the container (10). In a preferable embodiment of the present invention, the plug (9) is an elastomeric plug.

In a preferable embodiment of the present invention, the wick (8) is made of a mixture of nylon (polyamide) and one or more of a polyester or poly phenylene sulphide or poly ether sulphone material or a combination thereof.

In another preferable embodiment of the present invention, the wick (8) is made of 80% nylon and 20% polyester or poly phenylene sulphide or poly ether sulphone material or a combination thereof.

In yet another preferable embodiment of the present invention, the wick (8) is made of 80% nylon and 20% polyester.

The wick (8) of the present invention is thermostable at 220°C.

In another preferable embodiment of the present invention, the wick (8) has a high porosity.

When compared with the wicks used in the prior art, the wick of the present invention and those of the prior art display the following performance :-

Wick type Stability at 200 -220°C Release Life of Wick
Polyester wick Unstable, softens, deforms Not achieved Less than one cycle
Clay wick Unstable, pores clog Much lower than desired Less than 10 cycles
Wick of the present invention Stable Achieved (400 - 600 mg on Flash mode) Stable for 360 hours which is equivalent to 45 cycles

In a preferable embodiment of the invention, the wick (8) has a high porosity of up to 85%. Due to its high porosity, the wick (8) has the capacity to hold a minimum of 1500 mg of liquid viz. 2-3 times more than any wick as described in the prior art. The liquid in the container (10) is transported through the wick (8) by means of capillary action.

The device of the present invention is further provided with a heating assembly (5) whose heating surface is placed in close proximity to the upper portion of the wick (8). The heating assembly (5) is provided with a top cover (4) and a bottom cover (6). The top cover (4) and bottom cover (6) provide heat and electric insulation to the device from the heating assembly (5). The switch (2) which protrudes from the front cover (1) is connected to the PCB (3) which in turn is connected to the heating assembly (5) and is therefore able to change the mode of the device from flash mode to normal mode and vice versa.

In a preferable embodiment of the present invention, when the device is switched on, the temperature of the heating surface of the heating assembly (5) rises up to 220°C. Since the amount of liquid saturating the wick (8) is at least two to three times higher than the wicks of the prior art and as liquid evaporates at a much faster rate at higher temperatures, the liquid that is released into the air from the device of the present invention is at least four to five times more than that released from the devices of the prior art. Due to this, there is an instant burst or release of the said liquid in the initial hours of operation.

Furthermore, the device for vaporization of liquid of the present invention is provided with a device (23) for controlling the PTC Thermistor (high temperature) (19) i.e. one of the heating elements of the heating assembly (5) (shown in Fig.2). The device (23) for controlling the PTC Thermistor (high temperature) (19) is connected to the PCB (3). In normal mode, only the PTC Thermistor (low temperature) (16) i.e. the other heating element of the heating assembly (5), is operational. In the flash mode, PTC Thermistor (high temperature) (19) and the PTC Thermistor (low temperature) (16), both are operational.

In a preferable embodiment of the present invention, the said device (23) for controlling the PTC Thermistor (high temperature) (19) serves as a timer and regulates the operation of PTC Thermistor (high temperature) (19) in the heating assembly (5) for differential release of the liquid into the air in a cyclic manner at predetermined time intervals. The PTC Thermistor (high temperature) (19), when in operation, is responsible for raising the temperature of the heating surface of the heating assembly (5) to 220°C. Due to regulation of the PTC Thermistor (high temperature) (19) by the device (23), the temperature of the heating assembly (5) is subsequently lowered from 220°C after a predetermined time, which reduces the rate at which the liquid is evaporated and subsequently released into the air. The wick (8) is capable of remaining stable for 360 hours or 45 cycles while maintaining 400 to 600 mg of the said liquid in its heating zone which is in close proximity to the heating surface of the heating assembly (5).

Due to the initial burst or release of the liquid, the device provides quick efficacy of the active ingredient in the liquid at the onset and then subsequently maintains an optimal dose of the active ingredient in the air, as compared to the devices of the prior art. Below is a table of comparison between the release rates from the device of the present invention and the devices known in the prior art :-

Sr. No. Product Mode Active ingredient Content Efficacy KT 50
(In minutes)
1. Liquid vaporiser (Prior art) Normal mode disclosed in the prior art Transfluthrin 1.6 % w/w >100
2. Liquid vaporiser
(Prior art) Booster mode disclosed in the prior art Transfluthrin 1.6 %w/w >40
3. Present Invention Flash mode of the present invention Transfluthrin 1.6 %w/w <20

Unlike devices and systems of the prior art, when the system and device of the present invention is switched on, it operates in flash mode. The temperature is then controlled by the device (23) which in turn controls the PTC Thermistor (high temperature) (19). This enables the differential release of the liquid at regular time intervals. A user may, if so desired, change the mode to normal mode by means of the switch (2).

The heating assembly (5) is provided with a heating mechanism used in conjunction with the device (23) for controlling the PTC Thermistor (high temperature) (19), which cuts off the power supply to the said PTC Thermistor (high temperature) (19), when the desired high temperature is attained and maintained for a predetermined time. In a preferable embodiment, the device of the present invention, in flash mode, initially attains a temperature in the range of 170-220°C for quick action at the onset for a predetermined time, after which the temperature of the heating surface of the heating assembly (5) is lowered and is maintained in the temperature range of 140-160°C for a predetermined time. This is achieved by the device (23) which signals the thyristor (24) to shut the power supply to the PTC Thermistor (high temperature) (19) meant for maintaining the aforesaid high temperature in the range of 170-220°C. At this stage, since PTC Thermistor (high temperature) (19) is not provided with power supply, it is not in operation. Only PTC Thermistor (low temperature) (16) continues to operate. In flash mode, the temperature of the heating surface of the heating assembly (5) alternates between the above two temperature ranges in a cyclic manner at predetermined time intervals which is already fed or programmed into the device (23) for controlling the PTC Thermistor (high temperature) (19).

In case the device of the present invention is required to operate in the normal mode, the switch (2) protruding from the front cover (1) can be moved downward by the user. In the normal mode of operation, the temperature of the heating surface of the heating assembly (5) is constantly maintained in the range of 140-160°C.

As compared to the prior art, when the liquid is vaporized through the device of the present invention in flash mode, the released vapour reach free stream velocity in approximately 260 seconds. This is due to the judicious combination of the wick (8) made of nylon and one or more of a polyester or poly phenylene sulphide or poly ether sulphone material or a combination thereof, which is thermostable at a temperature of 220°C and also has a high porosity, and the close proximity of the heating surface of the heating assembly (5) to the upper portion of the wick (8). This enables the vapours to spread quickly to all corners of the room. As opposed to this, the liquid when vaporized through the devices known in the prior art, the vapour reaches free stream velocity in approximately 5 seconds. This implies that the vapour stream released from devices of the prior art, which usually operate at a temperature range of 140-160°C, lose their velocity quickly and get deflected very soon and are therefore not able to cover all corners of the room.

Figure 2 shows a circuit diagram of the PCB and the different electrical components of the device. The heating assembly (5) as shown in the figure consists of two PTC Thermistors (heating elements) i.e. PTC Thermistor (low temperature) (16) for normal mode and PTC Thermistor (high temperature) (19) for flash mode. The PCB is provided with one switch (2) to change the modes, and LED (21) to display the mode of operation. The connection of the above elements is shown in the figure 2.

A U-terminal (15) is used as a common terminal for the two PTC Thermistors. Neutral power (N) is given to the PTC Thermistor (low temperature) (16) and PTC Thermistor (high temperature) (19), through the said U-terminal (15). Further, two I-terminals (17/18) are used for the two PTC Thermistors i.e. PTC Thermistor (low temperature) (16) and PTC Thermistor (high temperature) (19), respectively. A phase power (P) is given through the I-terminals (17/18) for both the said thermistors (16) and (19) routed through PCB (3) which enables the device (23) to control the automated mode changes in Flash mode. The PCB (3) is further provided with a diode rectifier (22) and capacitor (20) which help to cut down alternate waves and to modify the current to direct currents for the device (23) to function. The device (23) to control the PTC Thermistor (high temperature) (19) will switch on and switch off the current supply to the PTC Thermistor (high temperature) (19) in flash mode by means of a thyristor (24), as per pre-determined time schedules already fed or programmed into the device (23). In normal mode, the PTC Thermistor (high temperature) (19) is not operational.
The heating assembly (5) can be operated at normal mode by operating i.e. supplying power only to the PTC Thermistor (low temperature) (16). In case of flash mode i.e. when the switch (2) is moved upward, the PTC Thermistor (high temperature) (19) and PTC Thermistor (low temperature) (16), both are operational. The heating assembly (5) functions in normal mode when the switch (2) is moved downward. The PTC Thermistor (low temperature) (16) operates when no differential or changed emanation or release of the liquid is desired. When the device functions in normal mode, the LED (21) glows green. To go back to the flash mode, the switch (2) is to be moved upward.

In a preferable embodiment of the present invention, the flash mode comprises of a cycle of 30 minutes of high emanation of liquid, at which time the temperature is maintained in the range of 170-220°C, followed by 210 minutes of low emanation of liquid, at which time the temperature is maintained in the range of 140-160°C. During the flash mode, the device (23) for controlling the PTC Thermistor (high temperature) (19) will signal the thyristor (24) to switch on the PTC Thermistor (high temperature) (19) as per the schedule which is already fed or programmed into the device (23). On expiry of the time for which the device is to be maintained at the temperature range of 170-220°C, the device (23) for controlling the PTC Thermistor (high temperature) (19) will switch off the power supply to PTC Thermistor (high temperature) (19), while supply of power to the PTC Thermistor (low temperature) (16) remains unaffected. Due to this, the temperature of the heating surface of the heating assembly (5) will be lowered. The above process is repeated in a cyclic manner. When the device is operating in flash mode, the LED (21) glows orange.

The device (23) for controlling the PTC Thermistor (high temperature) (19) regulates the release patterns of the liquid from the device. In particular, the PTC Thermistor (high temperature) (19) is routed through a thyristor (24) which will be controlled by the device (23) where the temperatures are maintained as per required protocol programming.

In yet another embodiment, the device according to the present invention is provided with an arrangement whereby the heating assembly (5) attains temperature in the range of 170-220°C initially for a predetermined time and thereafter drops down, but is constantly maintained at lower temperature of 140-160°C.

ADVANTAGES

1. Once the system and device of the present invention is switched on, there is very little or no lag time between the initiation of the system and device and the release of the liquid into the surrounding environment. Further, this invention also allows an initial burst or release of the liquid into the air followed by a subsequent continuous release of adequate liquid into the air.

2. The system and device provide automatic differential release of the liquid at predetermined time intervals in a cyclic manner.

3. The released vapour from the system and device reach free stream velocity in approximately 260 seconds, which enables the vapours to spread quickly to all corners of the room.

4. The wick of the present invention is thermostable at a temperature of 220°C and has a porosity of up to 85%. Due to this, the liquid that is released into the air from the system and device of the present invention is at least four to five times more than that released from the devices of the prior art.

5. It is an auto timer system and device in the field of household insecticides which work directly on house hold sockets with high efficacy.

Many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appendant claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
,CLAIMS:1. A system for vaporization of a liquid inter alia comprising,

a liquid stored in a container (10) having a wick (8) whose one end is immersed in the said liquid and the other end is protruding from the container (10),

a system to heat the end of the wick protruding from the container,

characterized by the fact that the wick (8) is of high porosity, is thermostable at 220°C and is made of nylon and one or more polyester, poly phenylene sulphide, poly ether sulphone or combination thereof; and

there is provided a device (23) to control and vary the temperature of the heating surface of the heating assembly (5).

2. A device for vaporization of a liquid inter alia comprising of a hollow container (10) with a closed bottom and an opening at the top, holding a liquid, a wick (8) whose one end is immersed in the said liquid and the other end is protruding from the top opening of the container (10), a heating assembly (5) whose heating surface is in close proximity to the other end of the wick (8) characterized by the fact that the wick (8) is made of nylon and one or more polyester, poly phenylene sulphide, poly ether sulphone or combination thereof such that it has high porosity and is thermostable at temperature up to 220°C; and a device (23) for controlling the PTC Thermistor (high temperature) (19) is connected to the heating assembly (5) to control and vary its temperature.

3. A device as claimed in Claim 2, wherein the wick (8) is made of 80% nylon and 20% polyester or poly phenylene sulphide or poly ether sulphone material or combination thereof.

4. A device as claimed in Claim 3, wherein the wick (8) is made of 80% nylon and 20% polyester.

5. A device as claimed in Claims 2 to 4, wherein the wick (8) has a porosity of up to 85%.

6. A device as claimed in Claim 2, wherein the temperature of the heating surface of the heating assembly (5) alternates between a temperature in the range of 170-220°C and a temperature in the range of 140-160°C for a predetermined time, in a cyclic manner.

7. A device as claimed in Claim 6, wherein the heating surface of the heating assembly (5) is maintained at a temperature in the range of 170-220°C for 30 minutes and at a temperature in the range of 140-160°C for 210 minutes.

8. A device as claimed in Claim 2, wherein the heating surface of the heating assembly (5) initially attains a temperature in the range of 170-220°C for a predetermined time and subsequently drops down to but is constantly maintained at a temperature in the range of 140-160 °C.

9. A wick (8) for use in a system and device for vaporization of liquid characterized by the fact that the wick (8) is made of nylon and one or more of a polyester or poly phenylene sulphide or poly ether sulphone material or combination thereof.

10. A wick (8) as claimed in Claim 9, wherein the wick (8) is made of 80% nylon and 20% polyester or poly phenylene sulphide or poly ether sulphone material or combination thereof.

11. A wick (8) as claimed in Claim 10, wherein the wick is made of 80% nylon and 20% polyester.

12. A wick (8) as claimed in Claims 9 to 11, wherein the porosity of the wick (8) is up to 85%.

Dated this 17th day of July, 2020

Sd/-
Himanshu W. Kane Applicant’s Patent Agent
IN/PA – 29