US20220338536A1 - Cartridge with stagnation pressure flow - Google Patents

Abstract

Various embodiments of the present technology may provide methods and apparatus for increasing a flow rate of a vaporizable liquid in a cartridge. The methods and apparatus for increasing the flow rate may include drawing air into an airflow path of the cartridge. The methods and apparatus for increasing the flow rate may also include diverting the air around a porous body disposed within the airflow path to form a stagnation pressure adjacent a first end of the porous body. The methods and apparatus for increasing the flow rate may further include increasing the flow rate in response to forming the stagnation pressure.

Description

CROSS-REFERENCE TO RELATED APPLICATION
• This application claims the benefit of U.S. Provisional Patent Application Ser. No. 63/176,034, filed on Apr. 16, 2021, and incorporates the disclosure of the application in its entirety by reference.
BACKGROUND OF THE TECHNOLOGY
• State of the Art
• Vaporizer devices present an alternative to smoking and work by vaporizing a consumable vaporizable liquid, e.g., oil or extract, by heating the vaporizable liquid at a lower temperature than an open flame so that a user can inhale the vaporizable liquid in vapor form, rather than smoke.
• A conventional cartridge of a vaporizer device typically has a reservoir for holding the vaporizable liquid, a wick capable of soaking up the vaporizable liquid, and a heated coil, in contact with the wick. A current is typically passed through the coil, heating the wick, and vaporizing the vaporizable liquid. However, the air that is introduced into a conventional cartridge typically flows through the heated coil, thereby diluting the vapor and making the heated coil draw more current than is necessary to heat the vaporizable liquid.
• Accordingly, what is needed is a cartridge that efficiently vaporizes the vaporizable liquid and that provides a user with high-quality vapor, consistent flavor profiles, and improved sensory experiences over the lifetime of the cartridge.
SUMMARY OF THE TECHNOLOGY
• Various embodiments of the present technology may provide methods and apparatus for increasing a flow rate of a vaporizable liquid in a cartridge. The methods and apparatus for increasing the flow rate may comprise drawing air into an airflow path of the cartridge. The methods and apparatus for increasing the flow rate may also comprise diverting the air around a porous body disposed within the airflow path to form a stagnation pressure adjacent a first end of the porous body. The methods and apparatus for increasing the flow rate may further comprise increasing the flow rate in response to forming the stagnation pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
• A more complete understanding of the present technology may be derived by referring to the detailed description and claims when considered in connection with the following illustrative figures. In the following figures, like reference numbers refer to similar elements and steps throughout the figures.
• FIG. 1 is a sectional view of a cartridge in accordance with an embodiment of the present technology; and
• FIG. 2 is a flow chart for increasing a flow rate of a vaporizable liquid in accordance with an embodiment of the present technology.
DETAILED DESCRIPTION OF EMBODIMENTS
• The subject technology may be described in terms of functional block components. Such functional blocks may be realized by any number of components configured to perform the specified functions and achieve the various results. For example, the subject technology may employ various, batteries, coils, heating elements, inlets, outlets, porous bodies, reservoirs, vaporizable liquids, extracts, oils, and the like, which may carry out a variety of functions. In addition, the present technology may be practiced in conjunction with any one of various vaporizer devices, and the cartridge described herein is merely one exemplary application for the technology.
• Referring to FIG. 1, an exemplary cartridge 100 may be integrated in any suitable vaporizer device (not shown) for vaporizing a vaporizable liquid. In various applications, the cartridge 100 may operate to increase a flow rate of the vaporizable liquid. According to various embodiments, the cartridge 100 may comprise a porous body 105 and a heating element 110. In some embodiments, the cartridge 100 may further comprise a reservoir 115.
• The porous body 105 may be disposed within an airflow path A of the cartridge 100 and may be suitably configured to wick the vaporizable liquid from the reservoir 115. The porous body 105 may comprise any suitable size or shape. For example, in one embodiment, the porous body 105 may be block-shaped. In an alternative embodiment, the porous body 105 may be cylindrical-shaped. In addition, the porous body 105 may be constructed from any suitable porous material, such as ceramic, cellulose, and the like.
• The heating element 110 may be positioned along the porous body 105. In one embodiment, the heating element 110 may be in contact with the porous body 105 and may heat the porous body 105 to a temperature sufficient to vaporize the vaporizable liquid flowing therethrough. The heating element 110 may comprise any suitable resistive element that dissipates heat when an electric current flows through it, such as a coil, ribbon, strip of wire, wire mesh, and the like. It will be appreciated that the heating element 110 may be constructed from a variety of suitable materials, such as copper, nickel, iron, stainless steel, or a combination thereof.
• The reservoir 115 may comprise any suitable reservoir or tank capable of holding a vaporizable liquid therein. The reservoir 115 may be in fluid communication with the porous body 105, such that the vaporizable liquid may flow from a first end 106 of the porous body 105 to a second end 107 of the porous body 105. The reservoir 115 may comprise any suitable size and shape. For example, in one embodiment, the reservoir may be cylindrical-shaped and may be configured to hold up to 5 or 6 ml of the vaporizer liquid. The reservoir 115 may be constructed from any suitable material, such as glass, plastic, and the like.
• In operation, and referring now to FIGS. 1-2, increasing the flow rate (200) of the vaporizable liquid may comprise drawing air into the airflow path A (205). The vaporizer device may be turned on by a sensor (not shown) or by pressing a button or switch. For example, in the case where the vaporizer device is “draw-activated”, a user may turn on the vaporizer device by drawing air into the vaporizer device via an inlet 101 of the cartridge 100 by inhaling through a mouthpiece (not shown) connected to an outlet 102 of the cartridge 100. When the user inhales, a negative pressure may be induced inside the vaporizer device. The negative pressure induced inside the vaporizer device may cause the sensor to close a pressure switch (not shown), thereby closing a circuit between a battery (not shown) and the various components of the vaporizer device. Once the pressure switch (not shown) is closed, the battery may supply power to the various components of the vaporizer device, including the heating element 110. The air may flow as an air stream upwards from the inlet 101 along the airflow path A. The relationship between the velocity, density, and pressure of the air stream may be expressed mathematically by the following expression:
• 
  P _{Static_1}+½ρν₁ ²+pgh ₁ =P _{Static_2}+½ρν₂ ²+pgh ₂
• where P_{static_1} is the static pressure at the first end 106 of the porous body 105, ν₁ is the velocity of the air stream at the first end 106 of the porous body 105, ρ is the density of the air stream, g is the gravitational force, h₁ is the height of the first end 106 above a reference point, P_{static_2} is the static pressure at the second end 107 of the porous body 105, ν₂ is the velocity of the air stream at the second end 107 of the porous body 105, and h₂ is a height of the second end 107 above the reference point.
• Accordingly, the difference between the static pressure P_{static_1} at the first end 106 of the porous body 105 and the static pressure P_{static_2} at the second end 107 of the porous body 105 may be described by the following equation:
• 
  P _{Static_1}−P _{Static_2}=½ρν₂ ²−½ρν₁ ²+ρg(h ₂−h ₁ )
• The distance d between the first end 106 of the porous body 105 and the second end 107 of the porous body 105 may be described by the following equation:
• 
  d=h ₂−h ₁
• In this regard, the difference between the static pressure P_{static_1} at the first end 106 of the porous body 105 and the static pressure P_{static_2} at the second end 107 of the porous body 105 may be described by the following equation:
• 
  P _{Static_1}−P_{Static_2}=½ρν₂ ²−½ρν₁ ²+ρgd
• After the air is drawn into the cartridge 100, increasing the flow rate of the vaporizable liquid may comprise diverting the resulting air stream around the porous body 105 to form a stagnation pressure adjacent the first end 106 of the porous body 105. In one embodiment, the air stream may be diverted along a first path 111 and a second path 112 around the porous body 105 disposed within the airflow path A to form a stagnation pressure adjacent the first end 106 of the porous body 105 and between the first path 111 and the second path 112 (210). The air stream may, however, be diverted around the porous body 105 in any suitable manner to form the stagnation pressure. As an example, the air stream may be diverted around the porous body 105 along a single path, two more paths, a circular path, and the like.
• Because a stagnation pressure is a static pressure at a stagnation point in the air stream and the stagnation point is a point in the air stream where the local velocity of the air stream is equal to zero, the difference between the stagnation pressure P_{stagnation_1} at the first end 106 if the porous body 105 and the static pressure P_{Static_2} at the second end 107 of the porous body 105 may be described by the following equation:
• 
  P _{Stagnation_1}−P _{Static_2}=½ρν₂ ⁺ ρgd
• Accordingly, diverting the air stream along the first path 111 and the second path 112 around the porous body 105 may increase the pressure drop across the distance d of the porous body 105 by ½ρν₁ ^2.
• Increasing the flow rate of the vaporizable liquid may further comprise increasing the flow rate in response to forming the stagnation pressure (215). Specifically, the flow rate may be proportional to the difference between the stagnation pressure P_{stagnation_1} at the first end 106 of the porous body 105 and the static pressure P_{static_2} at the second end 107 of the porous body 105. The flow rate may be expressed mathematically by the following expression:
• $q=\frac{k}{\mu d}\left(P_{\mathrm{Stagnation}\_1}-P_{\mathrm{Static}\_2}\right)$
• where q is the flow rate of the vaporizable liquid, k is the permeability of the porous body 105, μ is the dynamic viscosity of the vaporizable liquid, and d is the distance between the first end 106 of the porous body 105 and the second end 107 of the porous body 105.
• Because diverting the air stream along the first path 111 and the second path 112 around the porous body 105 may increase the pressure drop across the distance d of the porous body 105 by ½ρν₁ ², the flow rate of the vaporizable liquid may increase by
• $\frac{1}{2}\frac{k}{\mu d}\rho {v_1}^2.$
• In some embodiments, ρ, k, and μ may be known constants.
• While the air is drawn into the cartridge 100, the battery may supply a current to the heating element 110, where the current may flow through a coil 114 of the heating element 110 to dissipate heat. Because the coil 114 may be in contact with the porous body 105, the resulting heat may be transferred to the porous body 105. Further, because the air does not flow through the heating element 110 but is instead diverted around the porous body 105 and the heating element 110, the heating element 110 may heat the porous body 105 to a temperature sufficient to generate the vapor without drawing more current than is necessary to heat the vaporizable liquid. Once the vapor is produced, it may mix with the air drawn into the cartridge 100 via the inlet 101, and the resulting aerosol (vapor and airflow) may travel as an aerosol stream along the airflow path A where it may be expelled via the outlet 102 and inhaled through the mouthpiece of the vaporizer device.
• In the foregoing specification, the technology has been described with reference to specific embodiments. Various modifications and changes may be made, however, without departing from the scope of the present technology as set forth in the claims. The specification and figures are illustrative, rather than restrictive, and modifications are intended to be included within the scope of the present technology. Accordingly, the scope of the technology should be determined by the claims and their legal equivalents rather than by merely the examples described. For example, the components and/or elements recited in any apparatus claims may be assembled or otherwise operationally configured in a variety of permutations and are accordingly not limited to the specific configuration recited in the claims. Benefits, other advantages, and solutions to problems have been described above with regard to particular embodiments; however, any benefit, advantage, solution to problem or any element that may cause any particular benefit, advantage, or solution to occur or to become more pronounced are not to be construed as critical, required, or essential features or components of any or all the claims.
• As used herein, the terms “comprise,” “comprises,” “comprising,” “having,” “including,” “includes,” or any variation thereof, are intended to reference a non-exclusive inclusion, such that a process, method, article, composition, or apparatus that comprises a list of elements does not include only those elements recited but may also include other elements not expressly listed or inherent to such process, method, article, composition, or apparatus. Other combinations and/or modifications of the above-described structures, arrangements, applications, proportions, elements, materials, or components used in the practice of the present technology, in addition to those not specifically recited, may be varied, or otherwise particularly adapted to specific environments, manufacturing specifications, design parameters or other operating requirements without departing from the general principles of the same.

Claims (9)

1. A cartridge for use with a vaporizer device, comprising:

a porous body disposed within an airflow path of the cartridge, wherein air is drawn into the cartridge and diverted around the porous body to form a stagnation pressure adjacent a first end of the porous body; and

a heating element positioned adjacent a second end of the porous body.

2. The cartridge of claim 1, further comprising a reservoir capable of holding a vaporizable liquid therein, wherein:

the reservoir is in fluid communication with the porous body;

the stagnation pressure is greater than a reference pressure adjacent the second end of the porous body; and

the vaporizable liquid flows from the first end to the second end at a flow rate.

3. The cartridge of claim 2, wherein the reference pressure is a static pressure.

4. The cartridge of claim 3, wherein the flow rate is proportional to the difference between the stagnation pressure and the static pressure.

5. The cartridge of claim 1, wherein the porous body comprises ceramic, cellulose, cotton, silica, or a combination thereof.

6. A method for increasing a flow rate of a vaporizable liquid in a cartridge, comprising:

drawing air into an airflow path of the cartridge;

diverting the air around a porous body disposed within the airflow path to form a stagnation pressure adjacent a first end of the porous body; and

increasing the flow rate in response to forming the stagnation pressure.

7. The method of claim 6, wherein:

the stagnation pressure is greater than a reference pressure adjacent a second end of the porous body; and

the vaporizable liquid flows from the first end to the second end at a flow rate.

8. The method of claim 7, wherein the reference pressure is a static pressure.

9. The method of claim 8, wherein the flow rate is proportional to the difference between the stagnation pressure and the static pressure.

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