E-LIQUID DELIVERY SYSTEM FOR PERSONAL VAPORIZERS
FIG3 is a block diagram representation of a vaporizer system incorporating liquid preheating according to an embodiment of the invention
It has been found that the ability to controllably pump vaporizable liquids can be significantly affected by their viscosities. In some applications, it may be desirable to reduce the viscosity of a vaporizable liquid to enhance its flow properties and to achieve a precise, repeatable rate of delivery to the vaporization chamber. In many instances, this can be achieved by preheating the vaporizable liquid upstream of the micro-pump. FIG3 is a block diagram of a generalized vaporizer system 200 with a pre-heating arrangement. As shown in the block diagram, a micro-pump 250 such as a PZE pump is used to draw liquid from a reservoir 240 and into contact with a vaporization heating element 260 in a vaporization chamber 230. Prior to the liquid passing through the pump 250, however, the liquid passes through a preheat chamber 255, where the liquid undergoes temperature conditioning. Through preheating, the liquid is brought to a temperature selected to produce a desired viscosity, which, in turn, is tailored to allow precise, metered flow control of the liquid through the pump 250 and into the vaporization chamber 230. In some embodiments and for typical e-liquids, the desired temperature may be in a range of 75-95 °F. In particular embodiments, the desired temperature may be in a range of 78-82 °F and is preferably about 80 °F. The preheat chamber 255, pump 250, and primary heating element 260 are all controllable through control modules 292 of a main control unit 290 of the device. Temperature control for the preheat chamber 255 and heating element 260 may be accomplished through the use of thermostatic switches 294.
block diagram
230
vaporization chamber
280
user input arrangement
290
control unit
11
°F.Clause
294
thermostatic switches
250
pump
240
reservoir
255
preheat chamber
292
controllable through control modules
260
heating element
['1. A personal vaporizer comprising: an annular main body defining a main body interior; a vaporization chamber within the main body interior; a vaporization heating element disposed within the vaporization chamber, the vaporization heating element having a vaporization heating surface; an air flow passage from one or more air intake openings in the case wall to the vaporization chamber; a vaporization mixture flow passage extending from the vaporization chamber to an exit port; a liquid reservoir configured for storage of a vaporizable liquid and having a reservoir exit port; a liquid transport arrangement for transporting vaporizable liquid from the liquid reservoir to the vaporization chamber, the liquid transport arrangement comprising a first liquid flow duct extending from the reservoir exit port, and a piezoelectric pump operatively connected to the first liquid flow duct for drawing the vaporizable liquid from the reservoir, through the liquid flow duct, and into the vaporization chamber through a nozzle positioned adjacent or in contact with the vaporization heating element so that liquid exiting the nozzle is heated by the vaporization heating surface.']