Vaporization pipe with flame filter
A vaporizer device that uses a flame for vaporizing flavor and psychoactive compounds from smoking materials such as tobacco. The present device has a filter unit 34 with a porous flame filter 36. The flame filter 36 can be made of open-cell ceramic or metal foam, sintered ceramic or metal granules or other porous, heat resistant materials. In use, flame is supplied to the flame filter, and inhalation causes ambient air to enter the flame filter as well. The flame exhaust and ambient air are mixed within the flame filter and produce an air stream of intermediate temperature. The intermediate temperature air stream is hot enough to vaporize desirable components from the smoking material. The filter unit and pipe can attach with a ground glass joint.
The present application is a continuation-in-part of copending patent application Ser. No. 10/639,344, filed on Aug. 12, 2003 and which claims the benefit of priority from the following provisional patent applications: 60/366,809 filed on Mar. 22, 2002; 60/384,551 filed on May 29, 2002; 60/399,465 filed on Jul. 29, 2002; and 60/429,120 filed on Nov. 26, 2002, which are hereby incorporated by reference in their entirety.
FIELD OF THE INVENTIONThe present invention relates generally to smoking devices and vaporization devices. More particularly, the present invention relates to a pipe designed to provide vaporization by using heat from a flame.
BACKGROUND OF THE INVENTIONTobacco, kinnick kinnick, or other herbs are typically smoked by burning and inhaling the combustion fumes and smoke. In recent years, interest has grown in the technique of vaporization in which the smoking material is carefully heated so that the desired flavor and psychoactive components are liberated, and combustion is minimized.
Vaporization provides many benefits over smoking. When performed properly, vaporization does not produce nearly as much toxic and carcinogenic pyrolytic products as smoking. Also, vaporization is smoother and more flavorful, and lacks a burned taste that many find disagreeable. Further, vaporization allows more efficient use of smoking materials, since desired flavor and psychoactive compounds are not destroyed by combustion.
However, vaporization is difficult to perform, since vaporization only occurs in a relatively narrow temperature range. If the temperature is too low, desired compounds are not volatilized and nothing is inhaled; if the temperature is too high, combustion will occur, with its ill effects. For most smoking materials, vaporization is optimal in a temperature range of about 300-400 degrees Fahrenheit. The optimal temperature depends upon the compounds being vaporized.
Most vaporizers in use today are electrically powered. For vaporizing plant materials such as tobacco or essential oils, a temperature-controlled heat gun is often used. Electrical vaporization devices are inconvenient to use since they are not portable and require electrical line power. Typically, heat guns require several hundred watts of power. Also, electrical vaporization devices tend to be expensive.
Some vaporizer devices employ a burning carbonaceous fuel element as a heat source. These devices are best suited for use in cigarettes since the carbonaceous fuel element burns for several minutes. However, a continuously burning fuel element is not desired for vaporizing some materials. Exemplary vaporizer devices in the prior art are listed below:
U.S. Pat. No. 4,219,032 describes a smoking device using a fuel element.
U.S. Pat. No. 5,993,748 describes a vaporization device that is electrically powered.
U.S. Pat. No. 4,141,369 describes a vaporization device that is electrically powered.
U.S. Pat. No. 6,354,301 describes a vaporizer attachment for a pipe so that the pipe can be coupled to an electric heat gun.
U.S. Pat. No. 4,303,083 describes a vaporizer that is electrically powered.
It would be an advance in the art of vaporization devices to provide a vaporizer that operates without electrical power, is inexpensive, is easily transportable, is small, and is simple to operate. Such a device could be widely used by tobacco smokers and by users of medicinal herbs (e.g. mullein, kinnick kinnick) and essential oils. Such a device would also largely avoid the harmful effects of inhaling toxic pyrolytic compounds found in smoke and provide the other benefits of vaporization.
SUMMARYThe present invention includes a vaporization device having a pipe with a bowl for holding smoking material (e.g. tobacco or other medicinal plant-based materials), and a heat resistant and porous flame filter for receiving a flame, wherein the flame filter has a thickness of at least 0.02 inches. The flame filter can also have thickness of at least 0.1 inch, or in the range of 0.125-1 inches. In one embodiment, the flame filter is made of open cell ceramic foam, which can comprise silicon carbide, silicon, cordierite or other ceramics. The flame filter causes mixing between flame exhaust and ambient air.
The flame filter can also be made of bonded granules (e.g. sintered metal or ceramic granules), stacked discs (with each disc having at least one hole), a tangled lump of metal wire, or stacked screens, for example. Generally, the flame filter material should have a thermal conductivity of at least 30 W/mK. The pipe can also have an airflow shutter to automatically regulate the amount of airflow into the flame filter, and thereby regulate the temperature. The device can also have a means for indicating temperature, such as an electronic temperature sensor with a display, or a bimetallic strip that moves in response to temperature.
In one useful embodiment, the flame filter comprises open cell silicon carbide foam made by chemical vapor deposition. The foam can have about 40-120 or 60-100 pores-per-inch (PPI), for example.
The present invention also may have a filter housing for holding the flame filter. The filter housing can be made of thermally insulating material (e.g. wood) so that a user is protected from touching the hot flame filter. The filter housing can also be hollow to provide thermal insulation.
The present invention also includes a filter unit having a filter housing, a flame filter disposed in the housing, and a means for attaching the filter housing to a pipe. The filter unit of the present invention can be used with many different kinds and styles of smoking pipes and will transform conventional smoking pipe into a vaporization pipe. The means for attaching the pipe can be a threaded connection, magnet, clamp, hinge, ground glass joint, O-ring seal and the like.
The present invention provides a vaporizing pipe that vaporizes flavor compounds, medicinal compounds and psychoactive compounds from smoking material such as tobacco, mullein, passion flower, cloves, yohimbe, mint, tea, eucalyptus, chamomile and the like. Many of these plant materials have medicinal compounds that can be inhaled when vaporized.
The present vaporizer pipe can be used with a flame such as from a conventional butane lighter or a match. The vaporization pipe of the present invention has a heat resistant, porous flame filter disposed upstream from the smoking material. In operation, flame exhaust and ambient air are drawn into the flame filter. The flame filter causes mixing between the flame exhaust and ambient air, and also conducts heat between the flame exhaust and ambient air. The flame filter thereby creates an intermediate temperature (e.g. about 300-400 F) air stream capable of vaporizing without burning. The smoking material is in the path of the intermediate temperature air stream, and so volatile flavor and psychoactive compounds are vaporized from the smoking material. The intermediate temperature air stream and vaporized compounds are then inhaled. The flame filter can be made of many heat-resistant materials such as metals (e.g. refractory metals, noble metals), ceramics and the like. The material of the flame filter should be resistant to oxidation at high temperature, resistant to cracking under extreme thermal shock, and have a high thermal conductivity. In preferred embodiments of the invention, the flame filter comprises open-cell ceramic foam.
Definitions:
Heat resistant: Capable of not melting and maintaining its physical structure when exposed to heat from a small flame. Materials that oxidize slightly when exposed to flame (e.g. bronze, stainless steel) are considered heat resistant in the invention. However, combustible materials (e.g. carbon) are not heat resistant.
Porous: Having flow paths that create mixing of flame exhaust and air.
If essential oils are used, the smoking material can comprise glass or stainless steel wool, or ceramic foam or paper with the oil absorbed therein. The wool or foam will function as an inert carrier and will allow the essential oil to vaporize without dripping down into the pipe.
The pipe bottom 20 and filter housing 38 can be made of many different materials such as wood, glass, ceramic, metal or the like. Materials with low thermal conductivity such as wood are generally preferred, but not required in the invention. The filter housing 38 should also be made of a material with low thermal conductivity so that heat from the flame filter 36 does not escape to the exterior surfaces. The filter housing 38 can be made of wood, closed-cell ceramic foam, metal or the like. Alternatively, the filter housing has a hollow space 42 to provide low thermal conductivity. The pipe bottom 20 can also have a hollow space (not shown) for thermal insulation. The bowl 26 can be made of metal (e.g., stainless steel or brass), in which case it may be plated with a relatively chemically nonreactive metal such as silver, gold, platinum or chromium.
The present invention necessarily includes the porous flame filter 36. The flame filter is made of heat resistant material such as ceramic or metal (e.g. refractory metal). The flame filter is made of porous material. The flame filter can be made of many structures, such as open cell foam (ceramic or metal), sintered or bonded ceramic or metal granules, stacked ceramic or metal screens or porous plates, coils or tangled lengths of wire, or stacked discs with holes. If plates are used, the plates can each have many holes or a single hole. A stack of plates with holes or a hole is considered to be porous in the invention, even if the plates are made of nonporous material.
Preferably in the invention, the flame filter 36 and bowl 26 are located so that the intermediate temperature air stream 52 flows straight through the smoking material. For example, in
The flame filter 36 may be cylindrically shaped (although it is not necessarily cylindrical), with a diameter 56. The diameter may be selected to be within the range of about 0.125-1.0 inches (i.e. cross sectional area of about 0.015 square inch to about 1 square inch). The present invention includes embodiments where the flame filter is larger or smaller than this range. In one embodiment, the cross sectional area is about 0.1 to about 0.5 square inches. The present invention also includes embodiments where the flame filter is square, rectangular or any other shape in cross-section.
The porous flame filter 36 is essential in the invention. The flame filter 36 can be made of many different materials and structures, all of which are understood to be included in the invention and within the scope of the appended claims. Materials and structures suitable for the flame filter include:
Bonded granules—In this embodiment, the flame filter is made of granules of heat resistant materials bonded or sintered together. Examples include sintered bronze, brass, stainless steel, or other metals. Also included are sintered ceramics such as alumina, cordierite, or porcelain. Bonded silicon carbide granules can be used as well. The granules can have sizes in the range of about 100-2000 microns, for example. If metals are used, a chemically stable coating (e.g. gold or platinum) can be applied to prevent oxidation. The porosity (volume % of open space) should be relatively high, for example at least 20 or 30%. The pore size should be relatively large so that one can inhale easily; for example, the pore size can be about 100-1000 microns.
Stack of plates or screens—The flame filter can comprise a stack of at least two, preferably at least three or four metal screens. For example, conventional metal screens can be. used. In this case, the metal should have a relatively high thermal conductivity above about 30 W/mK (e.g. brass or silver). Also, the metal may be resistant to oxidation, or have a protective coating (e.g. gold or platinum). Alternatively, the flame filter can comprise a stack of at least two, preferably at least three or four ceramic or metal plates with holes. A series of plates with holes is considered to be ‘porous’ in the present invention and appended claims.
Metal wire—The flame filter can also comprise a web of metal wire (e.g. 20-30 gauge). The metal may be resistant to oxidation or have a protective coating (e.g. platinum or gold), and have a high thermal conductivity (e.g. copper, brass or silver). The metal wire can be tangled, coiled, folded or in any other configuration that creates mixing of air and flame exhaust and provides heat exchange. The metal wire can have a round cross-sectional shape, or can be flat ribbon.
Reticulated open-cell foam—The flame filter can also comprise open cell metal or ceramic foam. In this case, the foam can have a pores-per-inch (PPI) rating of about 30-120, more preferably in the range of 50-100 PPI, inclusive. If metal is used, it should be heat resistant, and possibly coated with a protective coating (e.g. gold, platinum or other platinum-family metals). If ceramic is used, the foam can be made by applying a ceramic slurry to a burnable (e.g. urethane) foam substrate, and then kiln-firing, as known in the art. Also, the ceramic foam can be made by chemical vapor deposition (CVD) onto a foam substrate, also as known in the art. If CVD ceramic foam is used, it can be made of silicon carbide, which has very high oxidation resistance and thermal shock capability, is relatively inert, and has high thermal conductivity, which are all desirable properties. CVD ceramic foam can also be made of silicon, which also has high thermal conductivity and heat resistance. Other possible materials for the ceramic foam include cordierite, zirconium-containing ceramics, or silica-containing ceramics, or combinations of these materials. Some ceramic materials may break apart or crack due to the thermal shock of the applied flame, which is undesirable. Hence, a ceramic material should be selected that can withstand the thermal shock. A particularly useful material for the flame filter is 80 PPI CVD silicon carbide open-cell foam. The foam may have a relative density (volume occupied by solid material) of about 5-25% or about 8-12%. It is also noted that not all of the cells need to be open; some cells can be closed, as often occurs in ceramic foam made from slurry applied to polymer foam.
Most generally, the flame filter can comprise any heat-resistant, porous material that causes mixing of and/or heat exchange between of the flame exhaust and air, and has a thickness of at least 0.02 inches, or at least 1 millimeter or 0.1 inches. Reticulated structures such as open cell foams are preferred, but the invention and appended claims include all the materials listed above. The flame filter should resist melting up to at least the temperature of the flame of course, and preferably resists oxidation up to about 1000 degrees Fahrenheit. Some oxidation is acceptable if it forms a protective coating. Also, the material of the flame filter (i.e. not including pore spaces), may have a thermal conductivity of at least 30 W/mK. Silicon carbide can have thermal conductivity of about 120 W/mK, and so provides good heat transfer. A high thermal conductivity facilitates heat transfer between the flame exhaust and ambient air, thereby ensuring that the intermediate temperature air stream has a uniform temperature.
The flame filter can have a protective coating (e.g. platinum) to protect it from oxidation and chemical reactions. A protective coating can be particularly useful in embodiments employing metals, such as metal wire or sintered metal granules.
It is also noted that the flame filter 36 can have a combustion catalytic coating (e.g. platinum or palladium or a combination thereof) for causing more complete combustion of the flame exhaust. This will tend to reduce the amount of harmful combustion products inhaled from the flame.
Also, it is noted that the filter can include means (e.g. threads, friction fit) for direct attachment to the pipe. Preferably, the flame filter is disposed in a filter housing, because the flame filter typically gets too hot to safely handle directly. If a filter housing is used, the flame filter can be attached to the pipe indirectly through the filter housing. It is understood that the flame filter is considered attached to the pipe even in embodiments where the flame filter is directly attached only to the filter housing.
It is noted that the filter unit 34 can attach to the pipe with many different mechanisms. Examples include magnetized components that attach by magnetic attraction, screw threads as shown in
It is noted that it is preferable for the bowl to be constructed such that air flows in a straight path through the smoking material (as in all the pipes shown). In other words, the air preferably exits the bottom of the bowl, opposite the filter. This tends to result in all the smoking material being exposed to the hot airflow. In some conventional pipes (e.g. large conventional tobacco pipes), by contrast, the bowl is constructed so that air exits the side of the bowl, thus requiring that the hot air make a 90-degree turn within the bowl. This tends to result in unvaporized smoking material on the side of the bowl furthest from the bowl exit, which is undesirable.
Optionally, an air gap exists between the flame filter 36 and the glass (e.g. glass tube 112 or male joint 102). The air gap can be 0.002″-0.040″ thick, for example. An air gap will tend to minimize the amount of heat dissipated into the glass.
The present invention is also directed toward only the filter unit, which has a flame filter inside the filter housing, and a means for attaching the filter housing to a pipe. The means for attaching the pipe can be a threaded connection, magnet, clamp, hinge, ground glass joint, O-ring seal, and the like. The present filter unit can be used with many different kinds of pipes and devices ordinarily intended for use as conventional smoking devices. In fact, the present filter unit can effectively transform a conventional smoking pipe into a vaporization device. For example, the filter unit can be combined with a water pipe or any other pipe known in the art, and the pipe will act as a vaporizer.
It is also noted that the present invention can be used to produce smoke, if desired. If smoke is desired, a large flame is provided to the flame filter. Smoke produced in the present device will tend to be smoother and more pleasant than smoke produced in a conventional pipe, but will contain the harmful substances known to occur in smoke.
It is noted in the present invention that ceramic materials are generally preferred over metals for use in the flame filter 36. This is because ceramics tend to be much more resistant to oxidation and corrosion at high temperatures. Metals such as brass, copper or bronze tend to oxidize, which produces unhealthful metal oxide particles, which are inhaled. Also, metal flame filters tend to create a metallic taste. Inert metals such as platinum or gold can be used (e.g. as a coating), but such materials are very expensive. Hence, relatively inert ceramics such as silicon carbide, silicon, cordierite, and zirconia are preferred. It is also noted that semiconductor materials such as silicon can be used for the flame filter (e.g. silicon foam), and such materials are understood to fall under the rubric of ceramic materials in the present disclosure. Nevertheless, it is understood that even oxidizable metals (e.g. brass, bronze, steel) will function to provide flame filtering and air mixing, and are therefore included in the present invention and scope of the appended claims.
Also, it is noted that combinations of materials can be used for the flame filter. For example, the flame filter can comprise a screen in combination with a metal or ceramic foam, or a coil of wire in combination with ceramic discs having holes.
It will be clear to one skilled in the art that the above embodiments may be altered in many ways without departing from the scope of the invention. Accordingly, the scope of the invention should be determined by the following claims and their legal equivalents.
Claims
1. A method for vaporizing smoking material, comprising the steps of:
- a) disposing smoking material in a bowl of a pipe having an inhalation end;
- b) disposing a heat resistant and porous flame filter upstream from the bowl;
- c) inhaling from the inhalation end so that flame exhaust is drawn into the flame filter, and the flame exhaust is mixed with ambient air in the flame filter;
- d) drawing the flame exhaust and ambient air mixture through the smoking material such that volatile components of the smoking material are vaporized.
2. A vaporization device, comprising:
- a) a pipe having: 1) a bowl for holding smoking material, and 2) an inhalation end for emitting vapors, wherein the inhalation end is disposed downstream from the bowl;
- b) a heat resistant and porous flame filter, with tortured flow paths, for receiving a flame, wherein the flame filter has a thickness of at least 0.02 inches, and wherein the flame filter is disposed upstream from the bowl;
- c) a filter housing for holding the flame filter, wherein the filter housing and the pipe attach via a ground glass joint or O-ring seal.
3. The vaporization device of claim 2, wherein the flame filter comprises a material selected from the group consisting of open cell foam, open cell ceramic foam, bonded granules, stacked discs, tangled wire, stacked screens, and combinations thereof.
4. The vaporization device of claim 2, wherein the filter housing comprises a male joint, and the pipe comprises a female joint.
5. The vaporization device of claim 2, wherein the filter housing comprises a female joint, and the pipe comprises a male joint.
6. The vaporization device of claim 2, wherein the ground glass joint is conical or spherical.
7. The vaporization device of claim 2, wherein the filter housing includes a step for supporting the flame filter.
8. The vaporization device of claim 2, further comprising a retaining ring disposed in the filter housing, for retaining the flame filter.
9. The vaporization device of claim 2, further comprising a finger attached to the filter housing, for retaining the flame filter.
10. The vaporization device claim 2, wherein the flame filter comprises silicon carbide ceramic foam and has a thickness of at lest 0.05 inches.
11. A filter unit for attachment to a pipe having a bowl for holding smoking material, and having an inhalation end for emitting vapors, wherein the inhalation end is disposed downstream from the bowl, the filter unit comprising:
- a) a filter housing;
- b) a heat resistant and porous flame filter disposed in the filter housing, wherein the flame filter has a thickness of at least 0.02 inches, and wherein the flame filter comprises a material selected from the group consisting of open cell foam, open cell ceramic foam, bonded granules, stacked discs, tangled wire, stacked screens, and combinations thereof;
- wherein the filter housing comprises a male or female ground glass joint for attaching the filter housing to the pipe such that the flame filter is disposed upstream from the bowl.
12. The filter unit of claim 11, wherein the filter housing comprises a male joint, and the pipe comprises a female joint.
13. The filter unit of claim 11, wherein the filter housing comprises a female joint, and the pipe comprises a male joint.
14. The filter unit of claim 11, wherein the filter housing includes a step for supporting the flame filter.
15. The filter unit of claim 11, wherein the flame filter comprises silicon carbide ceramic foam.
16. The filter unit of claim 11, wherein the flame filter has a thickness of at least 0.05 inches.
Type: Application
Filed: Sep 8, 2008
Publication Date: Feb 5, 2009
Inventor: Dan A. Steinberg (Blacksburg, VA)
Application Number: 12/231,942
International Classification: A24F 1/32 (20060101); A24D 3/06 (20060101);