Patent Publication Number: US-2021162087-A1

Title: Device for evaporating volatile substances

Description:
The present invention relates to a device for evaporating volatile substances which allows a rapid increase in the temperature and variation of the working cycles. 
     BACKGROUND OF THE INVENTION 
     Electric heaters with heated resistors have been widely used for decades in industry to evaporate fragrances and insecticides. There are various solutions adopted to convert the electric current into heat: ceramic heaters, metallic resistors, PTC, etc., the majority of the successful products on the market being based on a heater with an alternating current which has a relevant thermal mass, producing, as a result, a slow evaporation of the volatile substances into the air when it is switched on for the first time. 
     There are also solutions based on temperature acceleration which require a direct current power source requiring a battery capacitor or an AC/DC power source which represents a substantial increase in the cost of the product in comparison to the systems powered by direct current. 
     The solutions existing at present have a series of drawbacks, such as: 
     The low-cost alternating current heaters require a certain time to reach the working temperature which is transferred to the wick impregnated for the diffusion of the volatile substances. The user will wait a long time to notice the smell. 
     Additionally, when a direct current power source is required, this involves a greater cost for the final solution. 
     On the other hand, one of the most common problems in all these alternating current devices is the habituation to the fragrances due to the lack of automatic regulation of the device. Due to the constant release of fragrances, the users become accustomed. 
     In addition, the impregnated wicks used at present are mainly a cylindrical shape which means that they are not well optimised in terms of heat transfer from the heat source. 
     Another drawback of the devices known at present is the regulation of the diffusion of volatile substances since the existing devices are generally regulated by mechanical regulation which require manual interaction from the user or costly electronic regulation. 
     Therefore, an object of the present invention is to provide a device for evaporating volatile substances comprising a heater with a very low thermal mass which allows a rapid increase in the temperature and variation of the working cycles. 
     DESCRIPTION OF THE INVENTION 
     The cited drawbacks are resolved using the device for evaporating volatile substances, presenting other advantages which will be described below. 
     The device for evaporating volatile substances according to the present invention comprises a heater which heats a wick impregnated with said volatile substances and is characterised in that said heater is formed from a printed circuit board provided with at least one resistor. 
     Advantageously, said printed circuit board can also have one or several copper areas to increase the temperature. 
     To ensure the correct placement of the wick with respect to the heater, said printed circuit board comprises grooves for the passage of stops, the heater is joined to the wick by means of a support and said stops meet with said support, aligning the heater with the wick. 
     In order to improve evaporation of the volatile substances, said wick is flat. 
     In addition, the device for evaporating volatile substances according to the present invention also comprises a recipient with liquid with said volatile substances, said liquid impregnating the wick. 
     If desired, the device for evaporating volatile substances according to the present invention also comprises one or more sensors connected to the printed circuit board, such as a temperature, pressure, motion and/or presence sensor. 
     Advantageously, said printed circuit board is connected to an alternating current electric power network and to a microcontroller and/or to a switch which allows the working cycles to be controlled. 
     At least the following advantages are achieved with the device for evaporating volatile substances according to the present invention: 
     The heater has a very low thermal mass which allows rapid acceleration of the temperature of the wick. 
     The need for a direct current source for the heater is eliminated, making the device cheaper. 
     It provides cycles of high/low fragrance intensity, preventing the habituation of the users. 
     The heat emission area of the wick is optimised owing to its flat shape of the impregnated surface of the wick, allowing the most suitable evaporation of volatile substances to the air, with the minimum use of materials. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       To better understand the foregoing, a set of drawings is accompanied in which a practical embodiment is represented schematically and only by way of non-limiting example. 
         FIG. 1  is a perspective view of the device for evaporating volatile substances according to the present invention without its exterior casing; 
         FIG. 2  is a sectional elevation view of the device for evaporating volatile substances of  FIG. 1 ; 
         FIGS. 3 and 4  are front and rear views of the printed circuit board of the heater of the device for evaporating volatile substances according to the present invention; 
         FIG. 5  is a plan view of the device for evaporating volatile substances according to the present invention with its exterior casing, wherein the stops are shown in contact with the support of the wick. 
     
    
    
     DESCRIPTION OF A PREFERRED EMBODIMENT 
     As is shown in  FIGS. 1 and 2 , the device for evaporating volatile substances comprises a heater  1  which heats a wick  2 , causing the evaporation of the volatile substances. 
     One part of the wick  2  is placed in the interior of a recipient  5  containing a liquid with the volatile substances such that said liquid impregnates the wick  2  for the evaporation of the volatile substances when heated by means of the heater  1 . 
     The wick  2  is flat and thin for transporting the liquid which is evaporated in the air by capillary action. The wick  2  has both sides exposed to allow the evaporation of the volatile substances from any side. 
     As can be seen in greater detail in  FIGS. 3 and 4 , the heater  1  is formed from a printed circuit board  10  which is connected to an alternating current electric power source and comprises at least one resistor  11  and can have one or several copper areas. 
     As is seen in these figures, the resistors  11  are arranged on the face oriented towards the wick  2 , while the copper areas  12  are arranged on the opposing face. 
     This printed circuit board  10  also comprises temperature control means, such as a switch and/or a microcontroller, connected to an alternating/direct current power source without a transformer to control the heating service cycles. 
     These heating cycles allow a rapid acceleration of the temperature in the impregnated wick, from the inactive state, for more rapid evaporation of the volatile substances and to prevent the habituation to the fragrances of the volatile substances. 
     If desired, the printed circuit board  10  could comprise at least one sensor to detect various aspects such as the presence of the wick  2 , the temperature, light, a printed barcode or any other identification by optical means or another type. 
     To ensure the correct placement of the wick  2  with respect to the heater  1 , the wick  2  is mounted in a support  4  which, in the represented embodiment, is formed by two pieces with U-shaped section. 
     In turn, the printed circuit board  10  comprises grooves  13  for the placement of stops  3  which, in the assembled position, are in contact with the support  4  of the wick  2 , as can be seen in  FIG. 5 . 
     The functioning of the device for evaporating volatile substances according to the present invention is the following: 
     When a user wishes to use the evaporation device, they should connect it to the power source, such as the conventional power network, for example by means of a plug of the device itself which is not shown in the figures. 
     Owing to the presence of the resistors  11  on the printed circuit board  10 , the heater is rapidly heated to heat the part of the wick  2  with respect to said resistors  11  and cause the evaporation of the volatile substances. 
     Additionally, the user can control the working cycles of the evaporation device by means of the controller of the printed circuit board  10  or equally, to prevent the user from becoming habituated to the fragrance of said volatile substances. 
     In spite of the fact that reference has been made to a specific embodiment of the invention, it is evident to a person skilled in the art that the device for evaporating volatile substances described is capable of having numerous variations and modifications and that all the details mentioned can be substituted for others which are technically equivalent without departing from the scope of protection defined by the enclosed claims.