Aerosol generating device with cover element sensor

Abstract

To provide an aerosol-generating device comprising a cover element sensor.SOLUTION: An aerosol-generating device is provided which comprises: a housing; a cavity to receive an aerosol-generating article; an aperture at least partially defined by the housing, the aperture being positioned at an end of the cavity in order to insert the aerosol-generating article into the cavity through the aperture; a cover element arranged to move relative to the housing between a closed position, in which the cover element at least partially covers the aperture, and an open position, in which the aperture is at least partially uncovered; and a sensor arranged to provide an electrical signal indicative of a position of the cover element relative to the aperture.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an aerosol generating device comprising a movable cover element and a sensor arranged to provide an electrical signal indicative of the position of the cover element. The present invention also relates to an aerosol generating system comprising the aerosol generating device and an aerosol-generating article. [Background technology]

[0002] One type of aerosol generating system is an electrically operated smoking system. Known handheld electrically operated smoking systems generally include an aerosol generating device that includes a battery, control electronics, and an electric heater for heating an aerosol generating article specifically designed for use with the aerosol generating device. In some embodiments, the aerosol generating article includes an aerosol-forming substrate, such as a tobacco rod or tobacco plug, and a heater housed within the aerosol generating device is inserted into or disposed around the aerosol-forming substrate when the aerosol generating article is inserted into the aerosol generating device. In an alternative electrically operated smoking system, the aerosol generating article may include a capsule that contains an aerosol-forming substrate, such as loose tobacco.

[0003] In known electrically operated smoking systems, an aerosol-generating article may be received in a cavity of an aerosol generating device. Some aerosol generating devices may include a sliding cover that a user may slide over the opening of the cavity when the aerosol generating device is not in use. However, the functionality of such covers is typically limited. For example, covers are typically manually operated and do not interact with any other elements of the aerosol generating device.

[0004] It would be desirable to provide an aerosol generating device with a cover element that facilitates improved operation of the aerosol generating device. Summary of the Invention

[0005] According to a first aspect of the invention, there is provided an aerosol generating device comprising a housing, a cavity for receiving an aerosol-generating article, and an opening at least partially defined by the housing. The opening is located at an end of the cavity for inserting the aerosol-generating article into the cavity through the opening. The aerosol generating device also comprises a cover element arranged to move relative to the housing between a closed position in which the cover element at least partially covers the opening, and an open position in which the opening is at least partially uncovered. The aerosol generating device also comprises a sensor arranged to provide an electrical signal indicative of the position of the cover element relative to the opening.

[0006] Advantageously, the electrical signal provided by the sensor facilitates operation of other elements of the aerosol generation device in response to the position of the cover element, for example, in some embodiments described herein, the aerosol generation device may include an electric heater, the operation of which is dependent on the signal provided by the sensor.

[0007] The sensor may be positioned to directly sense the position of the cover element relative to the sensor.

[0008] The aerosol generating device may include an indicator element arranged to move relative to the sensor when the cover element moves between the closed and open positions, and the electrical signal provided by the sensor is determined by the position of the indicator element relative to the sensor. Advantageously, the indicator element may be optimized for sensing by the sensor. For example, the indicator element may include at least one of a size, shape, and material that may be optimized for sensing by the sensor.

[0009] The indicator element may be connected to the cover element. The indicator element may be directly connected to the cover element. The indicator element may be integrally formed with the cover element. The indicator element may be formed separately from the cover element and attached to the cover element. For example, the indicator element may be attached to the cover element by at least one of an adhesive, an interference fit, and a weld.

[0010] The indicator element may be arranged to move relative to the sensor and the cover element. For example, the aerosol generating device may include a mechanical linkage arranged to translate movement of the cover element between the closed and open positions into movement of the indicator element relative to the sensor.

[0011] Advantageously, the mechanical linkage may facilitate desired positioning of the cover element, the indicator element, and the sensor within the aerosol generating device.

[0012] Advantageously, the mechanical linkage may translate a desired motion of the cover element into a different motion of the indicator element that is optimized for sensing by the sensor, for example, the mechanical linkage may translate rotational motion of the cover element into translational motion of the indicator element relative to the sensor.

[0013] The cover element may be rotatable relative to the housing between a closed position and an open position. Advantageously, a rotatable cover element may be easier for a user to operate than a sliding cover element. For example, when a user holds the aerosol generating device in one hand, a rotational movement of the thumb of the same hand may be a more natural movement than a sliding motion. Thus, advantageously, a rotatable cover element makes it easier to hold the aerosol generating device in one hand and operate the cover element. Advantageously, holding the aerosol generating device in one hand and operating the cover element makes it easier to insert an aerosol-generating article into the cavity. For example, a user may hold the aerosol generating device in one hand and operate the cover element with the same hand while simultaneously holding the aerosol-generating article using the remaining hand to insert the aerosol-generating article into the cavity. Known devices require a user to use both hands to hold the aerosol generating device and to operate the cover element before the user can remove the article and insert it into the device.

[0014] The mechanical linkage may include at least one of a cam and a gear.

[0015] The cover element preferably includes a cover portion and a shaft portion extending from the cover portion, the cover portion being arranged to at least partially cover the opening when the cover element is in the closed position, and the shaft portion being received within the housing. Advantageously, the shaft portion may facilitate rotation of the cover element between the closed and open positions.

[0016] The cover portion and the shaft portion may be formed separately and attached to one another. For example, the cover portion and the shaft portion may be attached to one another using at least one of an adhesive, an interference fit, and a weld.

[0017] The cover portion and the shaft portion may be integrally formed, for example, the cover portion and the shaft portion may be formed as a single piece using a molding process.

[0018] The cover portion may be substantially planar.The cover portion may be disc-shaped.

[0019] The shaft portion preferably extends perpendicular to the cover portion.

[0020] In embodiments in which the aerosol generating device includes a mechanical linkage, the mechanical linkage may include at least one of a cam and a gear connected to a shaft portion of the cover element.

[0021] The shaft portion may be formed separately and attached to the cam and / or gear. For example, the shaft portion may be attached to the cam and / or gear using at least one of an adhesive, an interference fit, and / or a weld.

[0022] The shaft portion may be integrally formed with the cam and / or gear, for example, the shaft portion and the cam and / or gear may be formed as a single piece using a molding process.

[0023] In embodiments in which the aerosol generating device includes a mechanical linkage, the indicator element may include at least one of a cam, a cam follower, and a gear.

[0024] In embodiments in which the aerosol generating device includes a mechanical linkage, the indicator element may be connected to at least one of a cam, a cam follower, and a gear. The indicator element may be integrally formed with the cam, cam follower, or gear. The indicator element may be formed separately from and attached to the cam, cam follower, or gear. For example, the indicator element may be attached to the cam, cam follower, or gear by at least one of an adhesive, an interference fit, and welding.

[0025] The aerosol generating device preferably comprises a biasing mechanism arranged to bias the cover element away from the open position and towards the closed position. Advantageously, the biasing mechanism may eliminate the need for a user to manually move the cover element towards the closed position. Advantageously, the biasing mechanism may reduce the risk of the cover element accidentally moving away from the closed position and towards the open position. Advantageously, during use, the biasing mechanism may bias the cover element against an aerosol-generating article received in the recess, thereby preventing movement of the aerosol-generating article during use.

[0026] In embodiments where the aerosol generating device includes a mechanical linkage, the mechanical linkage may include a biasing mechanism.

[0027] The biasing mechanism may include a torsion spring. Advantageously, a torsion spring may be particularly suitable for providing a rotational biasing force, which may also be referred to as torque, to bias the rotatable cover element away from the open position and towards the closed position.

[0028] In embodiments in which the cover element includes a shaft portion, the torsion spring may be positioned to act directly on the shaft portion, for example, the cover element may include a tab extending from the shaft portion and positioned to engage an end of the torsion spring.

[0029] The biasing mechanism may include a first gear connected to the shaft portion of the cover element and a second gear connected to the torsion spring, the first gear engaging the second gear to translate torque from the torsion spring to the shaft portion.

[0030] The first gear and the shaft portion may be separately formed and attached to one another. For example, the first gear and the shaft portion may be attached to one another using at least one of an adhesive, an interference fit, and a weld.

[0031] The first gear and the shaft portion may be integrally formed, for example, the first gear and the shaft portion may be formed as a single piece using a molding process.

[0032] The biasing mechanism may include a spring holder in which the torsion spring is at least partially received, at least a portion of an outer surface of the spring holder forming the second gear.

[0033] The torsion spring may be held in the spring holder by an interference fit.

[0034] The biasing mechanism may include a cam surface with the spring holder engaging the cam surface to act as a cam follower when the spring holder rotates relative to the cam surface. The spring holder and cam surface are preferably arranged such that the spring holder moves relative to the sensor when the spring holder rotates during rotation of the cover element. The indicator element may include the spring holder. The indicator element may be connected to the spring holder.

[0035] When the cover element is in the closed position, the cam follower is preferably positioned a first distance from the sensor, and when the cover element is in the open position, the cam follower is preferably positioned a second distance from the sensor, the second distance being different from the first distance.

[0036] The cam surface may be at least partially defined by the housing.

[0037] The biasing mechanism may include a spring holder biasing element for biasing the spring holder towards the cam surface. The biasing mechanism may include a compression spring. The torsion spring is preferably a coiled torsion spring arranged to additionally function as a compression spring such that the spring holder biasing element is a torsion spring.

[0038] The biasing mechanism may include a cap, the torsion spring being positioned between the spring holder and the cap. Advantageously, the cap may retain the torsion spring within the spring holder.

[0039] The spring holder is preferably rotatable relative to the cap.The torsion spring preferably includes a first end that engages the cap and a second end that engages the spring holder.

[0040] The biasing mechanism preferably includes a spindle extending from the cap, the torsion spring extending around the spindle. The spring holder is preferably rotatable around the spindle. Advantageously, the spindle may facilitate correct positioning of the torsion spring during assembly of the biasing mechanism.

[0041] The spindle and the cap may be formed separately and attached to one another, for example, the spindle and the cap may be attached to one another using at least one of an adhesive, an interference fit, and a weld.

[0042] The spindle and the cap may be integrally formed, for example, the spindle and the cap may be formed as a single piece using a molding process.

[0043] The biasing mechanism may include a chassis on which at least one of the shaft portion, the torsion spring, the first gear, the second gear, the spring holder, the cap, and the spindle are received. The cap is preferably connected to the chassis to hold the spring holder and the torsion spring between the cap and the chassis. The cap is preferably connected to the chassis by an interference fit.

[0044] The aerosol generating device may include a first detent arranged to hold the cover element in the open position. Advantageously, the first detent increases the force required to rotate the cover element from the open position. Thus, the first detent may be particularly advantageous in embodiments in which the aerosol generating device includes a biasing mechanism. For example, the biasing force provided by the biasing mechanism may be insufficient to move the cover element from the open position when a portion of the aerosol generating device engages the detent. Thus, the aerosol generating device may require additional force from the user to overcome the first detent, at which point the biasing mechanism may be sufficient to continue rotating the cover element to the closed position.

[0045] The first detent can be disposed to engage a protrusion on at least one of the cover element, the cover portion, the shaft portion, the first gear, the second gear, and the spring holder. The first detent can be formed by at least one of the housing, the biasing mechanism cap, and the biasing mechanism chassis.

[0046] The aerosol generating device may comprise a second detent arranged to hold the cover element in a closed position. Advantageously, the second detent increases the force required to rotate the cover element out of the closed position. Thus, advantageously, the second detent may reduce the risk of the cover element accidentally opening.

[0047] The second detent can be disposed to engage a protrusion on at least one of the cover element, the cover portion, the shaft portion, the first gear, the second gear, and the spring holder. The second detent can be formed by at least one of the housing, the biasing mechanism cap, and the biasing mechanism chassis.

[0048] The aerosol generating device may include a first detent, a second detent, or both a first detent and a second detent.

[0049] In embodiments in which the aerosol generating device includes a first detent and a second detent, the aerosol generating device may include a common detent that functions as both the first detent and the second detent. The common detent may be arranged to engage a first protrusion on at least one of the cover element, the cover portion, the shaft portion, the first gear, the second gear, and the spring holder to hold the cover element in an open position. The common detent may be arranged to engage a second protrusion on at least one of the cover element, the cover portion, the shaft portion, the first gear, the second gear, and the spring holder to hold the cover element in a closed position.

[0050] In embodiments where the aerosol generating device includes separate first and second detents, at least one of the cover element, the cover portion, the shaft portion, the first gear, the second gear, and the spring holder may define a common protrusion, the common protrusion preferably being arranged to engage with the first detent when the cover element is in the open position, and the common detent preferably being arranged to engage with the second detent when the cover element is in the closed position.

[0051] The aerosol generation device may comprise a first mechanical stop arranged to prevent the cover element from moving beyond the closed position when the cover element is rotated from the open position to the closed position.

[0052] The first mechanical stop can be disposed to engage at least one of the cover element, the cover portion, the shaft portion, the first gear, the second gear, and the spring holder. The first mechanical stop can be formed by at least one of the housing, the biasing mechanism cap, and the biasing mechanism chassis.

[0053] The aerosol generating device may comprise a second mechanical stop arranged to prevent the cover element from rotating past the open position when the cover element is rotated from the closed position to the open position.

[0054] The second mechanical stop can be disposed to engage at least one of the cover element, the cover portion, the shaft portion, the first gear, the second gear, and the spring holder. The second mechanical stop can be formed by at least one of the housing, the biasing mechanism cap, and the biasing mechanism chassis.

[0055] The aerosol generating device may include a first mechanical stop, a second mechanical stop, or both a first mechanical stop and a second mechanical stop.

[0056] In embodiments in which the aerosol generating device includes a first mechanical stop and a second mechanical stop, the aerosol generating device may include a common mechanical stop that functions as both the first mechanical stop and the second mechanical stop. The common mechanical stop may be arranged to engage a first portion of at least one of the cover element, the cover portion, the shaft portion, the first gear, the second gear, and the spring holder to hold the cover element in an open position. The common mechanical stop may be arranged to engage a second portion of at least one of the cover element, the cover portion, the shaft portion, the first gear, the second gear, and the spring holder to hold the cover element in a closed position.

[0057] The housing can include a first housing and a second housing. The second housing can be disposed for movement relative to the first housing. The opening can be at least partially defined by the second housing. The cover element can be disposed for movement relative to the second housing between a closed position and an open position.

[0058] The aerosol generating device may comprise a latch mechanism arranged to hold the cover element in an open position and arranged to release the cover element when the second housing is moved relative to the first housing.

[0059] The latch mechanism is positioned to hold the cover element in an open position. Advantageously, the latch mechanism thus facilitates insertion of an aerosol-generating article into the cavity. For example, when a user is ready to use the aerosol generating device, the user may move the cover element from the closed position to the open position. When the cover element reaches the open position, the latch mechanism holds the cover element in the open position, eliminating the need for the user to hold the cover element in the open position while inserting an aerosol-generating article into the cavity.

[0060] In embodiments where the aerosol generating device includes a mechanical linkage, the mechanical linkage may include a latch mechanism.

[0061] The latch mechanism is preferably located within the second housing.

[0062] The aerosol generating device may comprise a closing mechanism arranged to move the cover element away from the open position and towards the closed position when the latch mechanism releases the cover element.

[0063] The latch mechanism is arranged to release the cover element and the closing mechanism is arranged to move the cover element to a closed position when the second housing is moved relative to the first housing. Thus, advantageously, the latch mechanism and the closing mechanism may provide automatic closure of the cover element when the second housing is moved relative to the first housing.

[0064] In embodiments where the aerosol generating device comprises a mechanical linkage, the mechanical linkage may include a closing mechanism.

[0065] The closure mechanism is preferably located within the second housing.

[0066] The second housing is preferably arranged for sliding movement relative to the first housing.

[0067] The second housing preferably at least partially defines a recess. The recess may include a first end defined by an opening and a second end opposite the first end, the second end being at least partially closed. Advantageously, when the aerosol-generating article is received in the recess, moving the second housing away from the first housing may also move the aerosol-generating article away from the second housing. Advantageously, moving the aerosol-generating article away from the first housing may facilitate removal of the aerosol-generating article from the aerosol generating device. Advantageously, facilitating removal of the aerosol-generating article by moving the second housing away from the first housing may prompt a user to move the second housing relative to the first housing when removing the aerosol-generating article. Thus, advantageously, a user is prompted to release the cover element from the latch mechanism such that the closing mechanism may move the cover element to a closed position when the aerosol-generating article is removed from the recess.

[0068] The latch mechanism can be arranged to release the cover element when the second housing moves away from the first housing.The latch mechanism can be arranged to release the cover element when the second housing moves towards the first housing.

[0069] The closing mechanism is preferably arranged to move the cover element to the closed position when the second housing is moved towards the first housing.

[0070] The latch mechanism may include a cam connected to a shaft portion of the cover element and defining a cam surface, and a cam follower positioned within the second housing and engaging the cam surface. The cam surface defines a detent in which the cam follower is received when the cover element is in the open position. Advantageously, when the cam follower is received within the detent, relative movement between the cam follower and the cam surface is prevented. Thus, when the cam follower is received within the detent, the shaft portion cannot rotate and the cover element is retained in the open position.

[0071] The cam follower and cam surface are preferably arranged such that when the cam rotates during rotation of the cover element, the cam follower moves relative to the sensor. The indicator element may include the cam follower. The indicator element may be connected to the cam follower.

[0072] When the cover element is in the closed position, the cam follower is preferably positioned a first distance from the sensor, and when the cover element is in the open position, the cam follower is preferably positioned a second distance from the sensor, the second distance being different from the first distance.

[0073] The cam and shaft portions may be formed separately and attached to one another, for example, the cam and shaft portions may be attached to one another using at least one of an adhesive, an interference fit, and a weld.

[0074] The cam and shaft portion may be integrally formed, for example, the cam and shaft portion may be formed as a single piece using a molding process.

[0075] The latch mechanism may include a cam follower biasing element arranged to bias the cam follower against the cam surface. Advantageously, the cam follower biasing element may facilitate movement of the cam follower into the detent when the cover element is moved to the open position. The cam follower biasing element may include a compression spring.

[0076] The latch mechanism may include a release pin positioned within the second housing and arranged to move relative to the second housing, the first housing arranged to engage the release pin when the second housing moves relative to the first housing to urge the release pin against the cam follower to disengage the cam follower from the detent.

[0077] The release pin is preferably movable between a first position in which the second housing moves away from the first housing and a second position in which the second housing moves towards the first housing, and the latch mechanism further includes a release pin biasing element arranged to bias the release pin towards the first position.

[0078] When the second housing moves toward the first housing, the first housing is preferably pressed against the first end of the release pin to overcome the biasing force of the release pin biasing element and move the release pin toward the second position. When the release pin is in the second position, the release pin preferably engages the cam follower to disengage the cam follower from the detent.

[0079] The release pin biasing element may include a compression spring.

[0080] The closing mechanism may include a cover biasing element arranged to bias the cover element towards the closed position. The cover biasing element may include a torsion spring.

[0081] In embodiments in which the cover element includes a shaft portion, the cover biasing element may engage the shaft portion.

[0082] In embodiments where the latch mechanism includes a cam, the cover biasing element may engage the cam.

[0083] The latch mechanism may include a first gear connected to a shaft portion of the cover element and a geared cam follower disposed within the second housing. A surface of the geared cam follower defines a second gear that engages the first gear. The latch mechanism also includes a first cam surface fixed relative to the second housing, with the geared cam follower engaging the first cam surface. The first cam surface defines a detent against which the geared cam follower is received when the cover element is in the open position. Advantageously, when the geared cam follower is received within the detent, relative movement between the cam follower and the first cam surface is prevented. Thus, when the cam follower is received within the detent, the shaft portion cannot rotate and the cover element is held in the open position.

[0084] The geared cam follower and the first cam surface are preferably arranged such that when the first gear rotates during rotation of the cover element, the geared cam follower moves relative to the sensor. The indicator element may include the geared cam follower. The indicator element may be connected to the geared cam follower.

[0085] When the cover element is in the closed position, the geared cam follower is preferably positioned a first distance from the sensor, and when the cover element is in the open position, the geared cam follower is preferably positioned a second distance from the sensor, the second distance being different from the first distance.

[0086] The first gear and the shaft portion may be separately formed and attached to one another. For example, the first gear and the shaft portion may be attached to one another using at least one of an adhesive, an interference fit, and a weld.

[0087] The first gear and the shaft portion may be integrally formed, for example, the first gear and the shaft portion may be formed as a single piece using a molding process.

[0088] The first cam surface may be defined by the second housing.

[0089] The latch mechanism may include a chassis defining a first cam surface, the chassis being fixed relative to the second housing.

[0090] The latch mechanism may include a cam follower biasing element arranged to bias the geared cam follower against the first cam surface. Advantageously, the cam follower biasing element may facilitate movement of the geared cam follower into the detent when the cover element is moved to the open position. The cam follower biasing element may include a compression spring.

[0091] The latch mechanism may include a release element positioned within the second housing and arranged to move relative to the second housing, the first housing arranged to engage the release pin when the second housing moves relative to the first housing to urge the release element against the geared cam follower to disengage the geared cam follower from the detent.

[0092] The release element is preferably movable between a first position in which the second housing moves away from the first housing and a second position in which the second housing moves towards the first housing, and the latch mechanism further includes a release element biasing element arranged to bias the release element towards the first position.

[0093] When the second housing moves toward the first housing, the first housing is preferably pushed against the first end of the release element to overcome the biasing force of the release element biasing element and move the release element toward the second position. When the release element is in the second position, the release pin preferably engages the geared cam follower to disengage the geared cam follower from the detent.

[0094] The release element biasing element may include a compression spring.

[0095] The closing mechanism may include a second cam surface fixed relative to the second housing, the release element being arranged to engage the second cam surface to rotate the release element from the second position to the third position The release element is arranged to engage the geared cam follower such that when the release element rotates from the second position to the third position, the release element rotates the geared cam follower to move the cover element from the open position to the closed position.

[0096] The second cam surface may be defined by the second housing.

[0097] The latch mechanism may include a chassis defining a second cam surface, the chassis being fixed relative to the second housing.

[0098] In embodiments in which the housing includes a first housing and a second housing, the sensor is preferably located within the first housing.

[0099] In embodiments in which the housing comprises a first housing and a second housing, the second housing may be removable from the first housing. Advantageously, removing the second housing from the first housing may facilitate cleaning of one or more internal components of the aerosol generating device.

[0100] The sensor may be arranged to provide at least one of an electrical signal indicative of the second housing being removed from the first housing and an electrical signal indicative of the second housing being attached to the first housing. Advantageously, the electrical signal indicative of whether the second housing is attached to the first housing facilitates operation of other elements of the aerosol generating device depending on whether the second housing is attached to the first housing. For example, in some embodiments described herein, the aerosol generating device may include an electric heater, the operation of which is dependent on the electrical signal indicative of whether the second housing is attached to the first housing.

[0101] In embodiments in which the aerosol generating device includes an indicator element, the sensor may be positioned to provide an electrical signal indicating that the second housing has been removed from the first housing when the sensor does not detect the indicator element.

[0102] In embodiments in which the aerosol generating device includes an indicator element, the sensor may be positioned to provide an electrical signal indicating that the second housing has been attached to the first housing when the sensor senses the indicator element.

[0103] In any of the embodiments described herein in which the aerosol generating device comprises an indicator element, the indicator element may include a magnetic material and the sensor may include at least one of a reed switch and a Hall effect sensor.

[0104] The indicator element may include an optical surface and the sensor may include an optical sensor. The optical surface may include a reflective material. The reflective material may include a metallic material.

[0105] An optical sensor may include an optical transmitter and an optical receiver. As used herein, the term "light" means electromagnetic radiation.

[0106] The optical transmitter is preferably configured to transmit light having at least one wavelength. The light may include at least one wavelength in the visible portion of the electromagnetic spectrum. The visible portion of the electromagnetic spectrum includes wavelengths from about 390 nanometers to about 700 nanometers. The light may include at least one wavelength in the infrared portion of the electromagnetic spectrum. The infrared portion of the electromagnetic spectrum includes wavelengths from about 700 nanometers to about 1 millimeter.

[0107] The optical receiver is preferably sensitive to at least one wavelength of light transmitted by the optical transmitter.

[0108] The light transmitter is preferably positioned to transmit light towards the indicator element. The light transmitter is preferably positioned to receive light transmitted from the light transmitter and reflected, scattered, or reflected and scattered by the indicator element.

[0109] The optical transmitter may include at least one of a light emitting diode and a laser.

[0110] The optical receiver may include at least one of a photodiode and a phototransistor.

[0111] The cover element is preferably positioned such that when the cover element is in the closed position, the cover element covers at least about 50 percent of the opening, more preferably at least about 60 percent of the opening, more preferably at least about 70 percent of the opening, more preferably at least about 80 percent of the opening, more preferably at least about 90 percent of the opening, and more preferably at least about 95 percent of the opening.

[0112] The cover element is preferably arranged such that when the cover element is in the closed position, the cover element completely covers the opening. In other words, the cover element is preferably arranged such that when the cover element is in the closed position, the cover element covers 100% of the opening. Advantageously, arranging the cover element to completely cover the opening when the cover element is in the closed position may prevent foreign objects from being inserted into the recess when the aerosol generating device is not in use.

[0113] The cover element is preferably positioned so that when the cover element is in the open position, the cover element covers less than about 5 percent of the opening.

[0114] The cover element is preferably positioned such that the openings are not completely covered when the cover element is in the open position. In other words, the cover element is preferably positioned such that the cover element does not cover any of the openings when the cover element is in the open position. Positioning the cover element such that the openings are not completely covered when the cover element is in the open position facilitates insertion of the aerosol-generating article into the recess.

[0115] The housing may include an end wall, the opening extending through a first portion of the end wall. The cover element is preferably arranged to overlie a second portion of the end wall when the cover portion is in the open position. Advantageously, arrangement of the cover element to overlie the second portion of the end wall when the cover portion is in the open position may reduce the risk of damage to the cover element when the aerosol generating device is used with the cover element in the open position.

[0116] In embodiments in which the cover element includes a shaft portion, the shaft portion preferably extends through an opening in the housing end wall, the opening preferably being located on a central portion of the end wall, the central portion being located between the first portion of the end wall and the second portion of the end wall.

[0117] In embodiments in which the housing includes a first housing and a second housing, the second housing preferably includes an end wall.

[0118] The aerosol-generating device preferably comprises a heater arranged to heat the aerosol-generating article when it is received in the cavity.

[0119] The heater may include an electric heater.

[0120] The electric heater may be positioned outside the cavity.

[0121] An electric heater may be positioned within the recess.

[0122] The electric heater may be positioned to extend around and over the exterior surface of the aerosol-generating article received within the cavity.

[0123] The electric heater may be in the form of a coil. The electric heater may be configured to heat the fluid transport structure. The aerosol generation device may comprise a fluid transport structure, the electric heater being arranged to heat the fluid transport structure. The fluid transport structure may comprise a wick. The electric heater may be in the form of a coil, the electric heater being wound around the fluid transport structure.

[0124] The electric heater may extend into the cavity. The electric heater may be arranged to be received within the aerosol-generating article when the aerosol-generating article is inserted into the cavity. The electric heater may be an elongated electric heater. The electric heater may be blade shaped. The electric heater may be pin shaped. The electric heater may be cone shaped.

[0125] The electric heater may include an induction heating element. In use, the induction heating element inductively heats the susceptor material to heat the aerosol-generating article received in the cavity. The susceptor material may form part of the aerosol-generating device. The susceptor material may form part of the aerosol-generating article.

[0126] The electric heater may include a resistive heating element, in use, an electric current is supplied to the resistive heating element to generate heat by resistive heating.

[0127] Suitable materials for forming the resistive heating element include, but are not limited to, semiconductors such as doped ceramics, "conductive" ceramics (such as, for example, molybdenum disilicide), carbon, graphite, metals, metal alloys, and composites made of ceramic and metallic materials. Such composites may include doped or undoped ceramics. Examples of suitable doped ceramics include doped silicon carbide. Examples of suitable metals include titanium, zirconium, tantalum, and platinum group metals. Examples of suitable metal alloys include stainless steel, nickel-containing, cobalt-containing, chromium-containing, aluminum-containing, titanium-containing, zirconium-containing, hafnium-containing, niobium-containing, molybdenum-containing, tantalum-containing, tungsten-containing, tin-containing, gallium-containing, manganese-containing, and iron-containing alloys, as well as nickel-, iron-, cobalt-, and stainless steel-based superalloys, Timetal®, and iron-manganese-aluminum-based alloys.

[0128] In some embodiments, the resistive heating element comprises one or more stamped sections of an electrically resistive material (such as stainless steel. Alternatively, the resistive heating element may comprise a heating wire or filament (e.g., Ni-Cr (nickel-chromium), platinum, tungsten, or alloy wire).

[0129] The electric heater may comprise an electrically insulating substrate, with the resistive heating element being provided on the electrically insulating substrate. The electrically insulating substrate may be a ceramic material such as zirconia or alumina. The electrically insulating substrate preferably has a thermal conductivity of about 2 watts per metre per kelvin or less.

[0130] The aerosol generating device preferably comprises a power supply and a controller. The controller is preferably arranged to provide power from the power supply to the electric heater during use of the aerosol generating device. The controller is preferably arranged to provide power from the power supply to the sensor during use of the aerosol generating device.

[0131] The controller is preferably arranged to control the supply of power to the electric heater in response to signals received from the sensor.

[0132] The controller is preferably arranged to provide power from the power supply to the electric heater in accordance with a predetermined heating cycle when the aerosol generating device is used to heat an aerosol-generating article received in the cavity.

[0133] The controller is preferably arranged to supply power from the power supply to the electric heater in accordance with a predetermined heating cycle only when the controller receives a signal from the sensor indicating that the cover element is in an open position.The controller is preferably arranged to prevent supplying power from the power supply to the electric heater in accordance with a predetermined heating cycle when the controller receives a signal from the sensor indicating that the cover element is in a closed position.

[0134] In embodiments where the electric heater includes a resistive heating element, the controller may be arranged to provide power from the power source to the resistive heating element in response to a predetermined pyrolysis cycle to clean the electric heater when no aerosol-generating article is received in the cavity. The pyrolysis cycle may clean the electric heater by pyrolysis of residue remaining on the electric heater after use of the aerosol-generating device to heat one or more aerosol-generating articles. Typically, the maximum temperature to which the electric heater is heated during the pyrolysis cycle is higher than the maximum temperature to which the electric heater is heated during a heating cycle for heating an aerosol-generating article. Typically, the total duration of the pyrolysis cycle is less than the total duration of the heating cycle.

[0135] The controller is preferably arranged to supply power from the power supply to the electric heater in accordance with a predetermined pyrolysis cycle only when the controller receives a signal from the sensor indicating that the cover element is in a closed position.The controller is preferably arranged to prevent supplying power from the power supply to the electric heater in accordance with a predetermined pyrolysis cycle when the controller receives a signal from the sensor indicating that the cover element is in an open position.

[0136] In embodiments where the housing includes a second housing removable from the first housing, the controller is preferably arranged to provide power from the power source to the electric heater only when the controller receives a signal from the sensor indicating that the second housing has been attached to the first housing. The controller is preferably arranged to prevent the provision of power from the power source to the electric heater when the controller receives a signal from the sensor indicating that the second housing has been removed from the first housing.

[0137] The power source may be a DC voltage supply. In a preferred embodiment, the power source is a battery. For example, the power source may be a nickel metal hydride battery, a nickel cadmium battery, or a lithium-based battery (e.g., a lithium cobalt battery, a lithium iron phosphate battery, or a lithium polymer battery). Alternatively, the power source may be another form of charge storage device, such as a capacitor. The power source may require recharging and may have a capacity that allows for the storage of sufficient energy to use the aerosol generating device with one or more aerosol-generating articles.

[0138] The aerosol generating device preferably comprises at least one air inlet, preferably in fluid communication with the upstream end of the cavity. In embodiments where the aerosol generating device comprises an elongated electric heater, the elongated electric heater preferably extends from the upstream end of the cavity into the cavity.

[0139] In embodiments where the housing includes a first housing and a second housing, the at least one air inlet may be formed by a gap between the first housing and the second housing. In embodiments where the second housing defines a heater opening through which the electric heater extends into the cavity, the heater opening is preferably in fluid communication with the at least one air inlet.

[0140] The aerosol generating device may include a sensor for detecting airflow indicative of a user taking a puff. The airflow sensor may be an electromechanical device. The airflow sensor may be any of a mechanical device, an optical device, an opto-mechanical device, and a microelectromechanical system (MEMS) based sensor. The aerosol generating device may include a manual switch for a user to initiate a puff.

[0141] The aerosol generating device may include a temperature sensor. The temperature sensor may be mounted on a printed circuit board. The temperature sensor may detect the temperature of the electric heater or the temperature of the aerosol-generating article received in the cavity. The temperature sensor may be a thermistor. The temperature sensor may include circuitry configured to measure the resistivity of the electric heater and to derive the temperature of the electric heater by comparing the measured resistivity to a calibration curve of resistivity versus temperature.

[0142] Advantageously, deriving the temperature of the electric heater may facilitate control of the temperature to which the electric heater is heated during use. The controller may be configured to adjust the power supply to the electric heater in response to changes in the measured resistivity of the electric heater.

[0143] Advantageously, deriving the temperature of the electric heater may facilitate detection of a puff, for example a measured decrease in temperature of the electric heater may correspond to a user puffing or inhaling on the aerosol generating device.

[0144] The aerosol generating device preferably includes an indicator to indicate when the electric heater is activated. The indicator may include a light which is activated when the electric heater is activated.

[0145] The aerosol generating device may include at least one external plug or socket and at least one external electrical contact that allows the aerosol generating device to be connected to another electrical device. For example, the aerosol generating device may include a USB plug or socket that allows the aerosol generating device to be connected to another USB-enabled device. The USB plug or socket may allow the aerosol generating device to be connected to a USB charging device to charge a rechargeable power source within the aerosol generating device. The USB plug or socket may accommodate data transfer to or from the aerosol generating device, or both to and from the aerosol generating device. The aerosol generating device may be connectable to a computer to transfer data to the aerosol generating device, such as a new heating profile for a new aerosol-generating article.

[0146] In embodiments in which the aerosol generating device comprises a USB plug or socket, the aerosol generating device may further comprise a removable cover for covering the USB plug or socket when not in use. In embodiments in which the USB plug or socket is a USB plug, the USB plug may additionally or alternatively be selectively retractable within the device.

[0147] According to a second aspect of the present invention there is provided an aerosol-generating system comprising an aerosol-generating device according to the first aspect of the present invention in any of the embodiments described herein, and the aerosol-generating system also comprises an aerosol-generating article comprising an aerosol-forming substrate.

[0148] As used herein, the term "aerosol-generating article" refers to an article that includes an aerosol-forming substrate that, when heated, releases a volatile compound that can form an aerosol.

[0149] The aerosol-forming substrate may comprise a tobacco plug. The tobacco plug may comprise one or more of powder, granules, pellets, shreds, spaghetti, strips, or sheets, including one or more of tobacco leaves, tobacco stem fragments, reconstituted tobacco, homogenized tobacco, extruded tobacco, and expanded tobacco. Optionally, the tobacco plug may comprise additional tobacco or non-tobacco volatile flavor compounds that are released upon heating of the tobacco plug. Optionally, the tobacco plug may also include a capsule, for example, containing additional tobacco or non-tobacco volatile flavor compounds. Such capsules may melt during heating of the tobacco plug. Alternatively, or in addition, such capsules may be crushed before, during, or after heating of the tobacco plug.

[0150] When the tobacco plug includes homogenized tobacco material, the homogenized tobacco material may be formed by agglomerating particulate tobacco. The homogenized tobacco material may be in the form of a sheet. The homogenized tobacco material may have an aerosol former content of greater than 5 percent on a dry weight basis. Alternatively, the homogenized tobacco material may have an aerosol former content of 5-30 percent by weight on a dry weight basis. The homogenized tobacco material sheet may be formed by agglomerating particulate tobacco obtained by grinding or otherwise comminuted one or both of tobacco lamina and tobacco stem, and alternatively or additionally, the homogenized tobacco material sheet may include one or more of tobacco dust, tobacco fines and other particulate tobacco by-products formed, for example, during tobacco processing, handling and transport. The homogenized tobacco material sheet may include one or more inherent binders, which may be tobacco intrinsic binders, one or more extrinsic binders (i.e., tobacco extrinsic binders), or a combination thereof, to assist in agglomerating the particulate tobacco. Alternatively, or in addition, the homogenized tobacco material sheet may include other additives, including, but not limited to, tobacco and non-tobacco fibers, aerosol formers, humectants, plasticizers, flavorants, fillers, aqueous and non-aqueous solvents, and combinations thereof. The homogenized tobacco material sheet is preferably formed by a casting process of a type that generally involves casting a slurry including particulate tobacco and one or more binders onto a conveyor belt or other support surface, drying the cast slurry to form a homogenized tobacco material sheet, and removing the homogenized tobacco material sheet from the support surface.

[0151] The aerosol-generating article may have a total length of from about 30 millimeters to about 100 millimeters. The aerosol-generating article may have an outer diameter of from about 5 millimeters to about 13 millimeters.

[0152] The aerosol-generating article may include a mouthpiece located downstream of the tobacco plug. The mouthpiece may be located at the downstream end of the aerosol-generating article. The mouthpiece may be a cellulose acetate filter plug. The mouthpiece is preferably approximately 7 millimeters in length, but may have a length of approximately 5 millimeters to approximately 10 millimeters.

[0153] The tobacco plug may have a length of approximately 10 mm.The tobacco plug may have a length of approximately 12 mm.

[0154] The tobacco plug may have a diameter of from about 5 millimeters to about 12 millimeters.

[0155] In a preferred embodiment, the aerosol-generating article has an overall length of between about 40 mm and about 50 mm. Preferably, the aerosol-generating article has an overall length of about 45 mm. Preferably, the aerosol-generating article has an outer diameter of about 7.2 mm.

[0156] The invention will now be further described, by way of example only, with reference to the accompanying drawings in which: [Brief description of the drawings]

[0157] [Figure 1] FIG. 1 is a cross-sectional view of an aerosol generating device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view of the aerosol generating device of FIG. 1 with the second housing moved relative to the first housing. [Diagram 3] FIG. 3 illustrates the rotational movement of the cover element of the aerosol generating device of FIGS. [Figure 4] FIG. 4 illustrates the rotational movement of the cover element of the aerosol generating device of FIGS. [Diagram 5] FIG. 5 illustrates the rotational movement of the cover element of the aerosol generating device of FIGS. [Figure 6] FIG. 6 is an exploded perspective view of the mechanical linkage of the aerosol generating device of FIGS. [Figure 7] FIG. 7 illustrates the operation of the mechanical linkage of FIG. [Figure 8] FIG. 8 illustrates the operation of the mechanical linkage of FIG. [Figure 9] FIG. 9 illustrates the operation of the mechanical linkage of FIG. [Figure 10] FIG. 10 illustrates the operation of the mechanical linkage of FIG. [Figure 11] FIG. 11 illustrates the operation of the mechanical linkage of FIG. [Figure 12] FIG. 12 illustrates the operation of the mechanical linkage of FIG. [Figure 13] FIG. 13 illustrates the operation of the mechanical linkage of FIG. [Figure 14] FIG. 14 illustrates the operation of the mechanical linkage of FIG. [Figure 15] FIG. 15 illustrates the operation of the mechanical linkage of FIG. [Figure 16] FIG. 16 illustrates the operation of the mechanical linkage of FIG. [Figure 17] FIG. 17 illustrates the operation of the mechanical linkage of FIG. [Figure 18] FIG. 18 illustrates the operation of the mechanical linkage of FIG. [Figure 19] FIG. 19 is an exploded perspective view of an alternative arrangement of the mechanical linkage of the aerosol generating device of FIGS. 1 and 2. [Figure 20] FIG. 20 illustrates the operation of the mechanical linkage of FIG. [Figure 21] FIG. 21 illustrates the operation of the mechanical linkage of FIG. [Figure 22] FIG. 22 illustrates the operation of the mechanical linkage of FIG. [Figure 23] FIG. 23 illustrates the operation of the mechanical linkage of FIG. [Figure 24]FIG. 24 illustrates the operation of the mechanical linkage of FIG. [Diagram 25] FIG. 25 illustrates the operation of the mechanical linkage of FIG. [Figure 26] FIG. 26 illustrates the operation of the mechanical linkage of FIG. [Figure 27] FIG. 27 illustrates the operation of the mechanical linkage of FIG. [Figure 28] FIG. 28 illustrates the operation of the mechanical linkage of FIG. [Figure 29] FIG. 29 illustrates the operation of the mechanical linkage of FIG. [Diagram 30] FIG. 30 is an exploded perspective view of a further alternative arrangement of the mechanical linkage of the aerosol generating device of FIGS. 1 and 2. [Diagram 31] FIG. 31 is a perspective view of the mechanical linkage of FIG. [Diagram 32] FIG. 32 is a cross-sectional view of an aerosol-generating article for use with the aerosol generating device of FIGS. 1 and 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0158] 1 and 2 are cross-sectional views of an aerosol generating device 10 according to an embodiment of the present invention. The aerosol generating device 10 comprises a housing 12 including a first housing 14 and a second housing 16. The second housing 16 is slidable relative to the first housing 14 between a compressed position shown in FIG 2 and an extended position shown in FIG 1. Additionally, the second housing 16 is removable from the first housing 14.

[0159] The aerosol generating device 10 also includes a controller 18 positioned within the first housing 14, a power source 20, and a heater 22 extending from an end of the first housing 14. The power source 20 is a power supply that includes a rechargeable battery. The heater 22 is an electric heater that includes a resistive heating element 24. In use, the controller 18 provides power from the power source 20 to the resistive heating element 24 to resistively heat the heater 22.

[0160] A sensor 26 and a first magnet 28 are positioned on the first housing 14 next to the heater 22. The sensor 26 is an optical sensor including an optical transmitter and an optical receiver. The optical transmitter is an infrared emitting diode and the optical receiver is a photodiode. The photodiode is sensitive to the infrared light transmitted from the infrared emitting diode. An optical window 30 is over the sensor 26, the optical window being transparent to the infrared light transmitted from the infrared emitting diode.

[0161] The second housing 16 defines a cavity 32 for receiving an aerosol-generating article and an opening 34 located at an end of the cavity 32. When the second housing 16 is attached to the first housing 14, the heater 22 extends into the cavity 32 through a heater opening 36 defined by the second housing 16. An air inlet 38 is formed by the gap between the first housing 14 and the second housing 16. The air inlet 38 is in fluid communication with the cavity 32 through an airflow opening 40 defined by the second housing 16.

[0162] When an aerosol-generating article is received in cavity 32, the aerosol-generating article and aerosol-generating device 10 together form an aerosol-generating system. During use, heater 22 heats the aerosol-generating article received in cavity 32 to generate an aerosol. When a user draws on the aerosol-generating article, air is drawn through air inlet 38 into aerosol-generating device 10 and through airflow opening 40 into cavity 32. The air then flows through the aerosol-generating article to deliver the generated aerosol to the user.

[0163] The aerosol generating device 10 also includes a cover element 42 including a cover portion 44 overlying an end wall 46 of the second housing 16 and a shaft portion 48 extending through the end wall 46. The cover element 42 is rotatable between a closed position in which the cover portion 44 covers the opening 34 and an open position in which the cover portion 44 does not cover the opening 34. The closed position is shown in Figure 2 and the open position is shown in Figure 1. Figures 3-5 illustrate the rotation of the cover element 42 from the closed position (Figure 3) to the open position (Figure 5).

[0164] Located within second housing 16 is a mechanical linkage 50 that is arranged to interact with shaft portion 48 of cover element 42. An exploded view of mechanical linkage 50 is shown in FIG.

[0165] The mechanical linkage 50 includes a chassis 152 that is attached to the second housing 16 by screws 54. A second magnet 56 is mounted on the chassis 152 and positioned to interact with the first magnet 28 on the first housing 14. Specifically, the first magnet 28 and the second magnet 56 are magnetically attracted to each other, facilitating attachment of the second housing 16 to the first housing 14.

[0166] Also mounted on chassis 152 are latch mechanism 158 and closing mechanism 159 , which include a bushing 160 , a cam 162 , a cam follower 164 , a cam follower biasing spring 165 , a torsion spring 166 , a release pin 168 , and a release pin biasing spring 169 .

[0167] The cam 162 is connected to the end of the shaft portion 48 of the cover element 42 by an interference fit. Thus, when the cover element 42 rotates between the closed and open positions, the cam 162 also rotates. The bushing 160 and the torsion spring 166 are coaxially positioned about the shaft portion 48 of the cover element 42.

[0168] The cam follower 164 is slidably received within the chassis 152 and engages a first cam surface 163 formed on the cam 162. Thus, as the cam 162 rotates during rotation of the cover element 42, the cam follower 164 moves up and down within the chassis 152. The indicator element 74, which includes a light-reflective aluminum layer, is positioned on a bottom surface of the cam follower 164. As the cam follower 164 moves up and down within the chassis 152, the sensor 26 senses a change in the distance between the sensor 26 and the indicator element 74. Based on the sensed distance between the sensor 26 and the indicator element 74, the sensor 26 provides a signal to the controller 18 indicative of whether the cover element 42 is in a closed or open position.

[0169] If the signal from sensor 26 indicates that cover element 42 is in the closed position, it is assumed that an aerosol-generating article is not received in recess 32, and controller 18 does not supply power from power source 20 to heater 22 to heat the aerosol-generating article.

[0170] When the signal from sensor 26 indicates that cover element 42 is in the open position, an aerosol-generating article may be received in recess 32 and controller 18 may supply power from power source 20 to heater 22 to heat the aerosol-generating article.

[0171] If the sensor 26 fails to detect the indicator element 74, it is assumed that the second housing 16 has been removed from the first housing 14. In this case, the sensor 26 may provide a signal to the controller 18 indicating that the second housing 16 has been removed from the first housing 14, and the controller 18 may prevent the supply of power to the heater 22.

[0172] The operation of the latch mechanism 158 and the closing mechanism 159 will now be described with reference to Figures 7 to 18.

[0173] Figure 7 shows the cover element 42 in the closed position. As shown in Figure 8, when the cover element 42 is in the closed position, the cam follower 164 is biased to a lowered position by the cam follower biasing spring 165 and the release pin 168 is maintained in a raised position by the first housing 14.

[0174] As the cover element 42 rotates toward the open position, the rotation of the cam 162 raises the cam follower 164 to a raised position against the force of the cam follower biasing spring 165, loading the torsion spring 166. As shown in Figure 10, the release pin 168 remains in its raised position.

[0175] As shown in Figure 11, when cover element 42 reaches the open position, cam follower 164 is received within detent 171 defined by first cam surface 163 of cam 162. When cam follower 164 is received within detent 171, torsion spring 166 cannot rotate cam 162 and cover element 42 returns toward the closed position. As shown in Figure 12, release pin 168 remains in its raised position.

[0176] 13 and 14, as the second housing 16 moves away from the first housing 14, the release pin biasing spring 169 urges the release pin 168 to a lowered position. As the release pin 168 moves to its lowered position, a protrusion 173 on the release pin 168 engages a second cam surface 175 defined by the chassis 152, which rotates the release pin 168 to position the protrusion 173 below the cam follower 164.

[0177] As the second housing 16 moves toward the first housing 14, the first housing 14 pushes the release pin 168 upward against the force of the release pin biasing spring 169. As the release pin 168 moves upward, a protrusion 173 on the release pin 168 engages the cam follower 164, pushing the cam follower 164 toward its raised position, as shown in Figures 15 and 16. As the cam follower 164 is pushed toward its raised position, the cam follower 164 disengages from a detent 171 defined by the first cam surface 163 of the cam 162.

[0178] As shown in FIG. 17, when the cam follower 164 disengages from the detent 171 defined by the first cam surface 163 of the cam 162, the torsion spring 166 rotates the cam 162 to return the cover element 42 to the closed position. At the same time, the first housing 14 continues to urge the release pin 168 upward, causing a protrusion 173 on the release pin 168 to engage a third cam surface 177 defined by the second housing 16. As shown in FIG. 18, the third cam surface 177 rotates the protrusion 173 away from the cam follower 164 such that the release pin 168 disengages the cam follower 164. At this point, the latch mechanism 158 and the closing mechanism 159 have returned to the initial configuration shown in FIGS. 7 and 8.

[0179] FIG. 19 is an exploded view of an alternative arrangement of mechanical linkage 50.

[0180] The alternative mechanical linkage includes a chassis 252 attached to the second housing 16 by screws 54. Mounted on the chassis 252 is a second magnet 56 positioned to interact with the first magnet 28 on the first housing 14. Specifically, the first magnet 28 and the second magnet 56 are magnetically attracted to each other, facilitating attachment of the second housing 16 to the first housing 14.

[0181] Also mounted on the chassis 252 are a latch mechanism 258 and a closing mechanism 259 , which include a washer 260 , a first gear 262 , a geared cam follower 264 , a cam follower biasing spring 265 , a release element 268 and a release element biasing spring 269 .

[0182] The washer 260 is formed from a low friction material and facilitates rotation of a first gear 262 on the chassis 252. The first gear 262 is connected to the end of the shaft portion 48 of the cover element 42 by an interference fit. Thus, when the cover element 42 rotates between the closed and open positions, the first gear 262 also rotates.

[0183] The geared cam follower 264 is slidably received within the chassis 252 and engages with a first gear 262 and a first cam surface 263 formed by the chassis 252. Thus, as the first gear 262 rotates during rotation of the cover element 42, the geared cam follower 264 moves up and down within the chassis 252. The indicator element 74, which includes a light-reflective aluminum layer, is positioned on a bottom surface of the geared cam follower 264. As the geared cam follower 264 moves up and down within the chassis 252, the sensor 26 senses a change in the distance between the sensor 26 and the indicator element 74. Based on the sensed distance between the sensor 26 and the indicator element 74, the sensor 26 provides a signal to the controller 18 indicative of whether the cover element 42 is in a closed or open position.

[0184] If the signal from sensor 26 indicates that cover element 42 is in the closed position, it is assumed that an aerosol-generating article is not received in recess 32, and controller 18 does not supply power from power source 20 to heater 22 to heat the aerosol-generating article.

[0185] When the signal from sensor 26 indicates that cover element 42 is in the open position, an aerosol-generating article may be received in recess 32 and controller 18 may supply power from power source 20 to heater 22 to heat the aerosol-generating article.

[0186] If the sensor 26 fails to detect the indicator element 74, it is assumed that the second housing 16 has been removed from the first housing 14. In this case, the sensor 26 may provide a signal to the controller 18 indicating that the second housing 16 has been removed from the first housing 14, and the controller 18 may prevent the supply of power to the heater 22.

[0187] The operation of the latch mechanism 258 and the closing mechanism 259 will now be described with reference to Figures 20-29.

[0188] Figure 20 shows the cover element 42 in the closed position. As shown in Figure 21, when the cover element 42 is in the closed position, the geared cam follower 264 is biased to a lowered position by the cam follower biasing spring 265 and the release element 268 is maintained in a raised position by the first housing 14. As shown in Figures 28 and 29, in the raised position, an internal rib 290 on the release element 268 engages an external rib 292 on the geared cam follower 264.

[0189] As the cover element 42 rotates toward the open position, the rotation of the first gear 262 rotates the geared cam follower 264, which rotates the release element 268. As shown in FIG. 22, during rotation of the geared cam follower 264, the first cam surface 263 raises the geared cam follower 264 to a raised position against the force of the cam follower biasing spring 265. As shown in FIG. 23, when the cover element 42 reaches the open position, the geared cam follower 264 is received within a detent 271 defined by the first cam surface 263. When the geared cam follower 264 is received within the detent 271, the cover element 42 cannot rotate back toward the closed position.

[0190] As the second housing 16 moves away from the first housing 14, the release element biasing spring 269 urges the release element 268 to the lowered position, which disengages an internal rib 290 on the release element 268 from an external rib 292 on the geared cam follower 264. As shown in FIGS. 24 and 25 , while the release element 268 moves to its lowered position, a first protrusion 273 on the release element 268 engages a second cam surface 275 defined by the chassis 252, which rotates the release element 268 to a position where the second protrusion 280 is positioned below a third cam surface 282 defined by the chassis 252.

[0191] As the second housing 16 moves towards the first housing 14, as shown in FIG. 26, the first housing 14 pushes the release element 268 upward against the force of the release element biasing spring 269. As the release element 268 moves upward, an internal rib 290 on the release element 268 engages an external rib 292 on the geared cam follower 264, disengaging the geared cam follower 264 from the detent 271. At the same time, as shown in FIG. 27, a second protrusion 280 on the release element 268 engages a third cam surface 282, which rotates the release element 268, geared cam follower 264 and cover element back to the initial configuration shown in FIGS. 20 and 21.

[0192] 30 and 31 show a further alternative arrangement of the mechanical linkage 50. In FIG.

[0193] A further alternative mechanical linkage includes a chassis 52 attached to the second housing 16 by screws 54. Mounted on the chassis 52 is a second magnet 56 positioned to interact with the first magnet 28 on the first housing 14. Specifically, the first magnet 28 and the second magnet 56 are magnetically attracted to one another, facilitating attachment of the second housing 16 to the first housing 14.

[0194] Also mounted on chassis 52 is a biasing mechanism 58 , which includes a washer 60 , a first gear 62 , a spring holder 64 , a torsion spring 66 , a spindle 68 and a cap 70 .

[0195] The washer 60 is formed from a low friction material and facilitates rotation of a first gear 62 on the chassis 52. The first gear 62 is connected to the end of the shaft portion 48 of the cover element 42 by an interference fit. Thus, when the cover element 42 rotates between the closed and open positions, the first gear 62 also rotates.

[0196] An outer surface of the spring holder 64 forms a second gear 72 that engages with the first gear 62. The spring holder 64 is rotatably received within the chassis 52 and engages a cam surface formed on the chassis 52. Thus, as the spring holder 64 rotates relative to the cam surface, the spring holder 64 acts as a cam follower and moves up and down along the spindle 68. An indicator element 74 including a light-reflective aluminum layer is positioned on a bottom surface of the spring holder 64. As the spring holder 64 moves up and down along the spindle 68, the sensor 26 senses a change in the distance between the sensor 26 and the indicator element 74. Based on the sensed distance between the sensor 26 and the indicator element 74, the sensor 26 provides a signal to the controller 18 indicative of whether the cover element 42 is in a closed or open position.

[0197] If the signal from sensor 26 indicates that cover element 42 is in the closed position, it is assumed that an aerosol-generating article is not received in recess 32, and controller 18 does not supply power from power source 20 to heater 22 to heat the aerosol-generating article.

[0198] When the signal from sensor 26 indicates that cover element 42 is in the open position, an aerosol-generating article may be received in recess 32 and controller 18 may supply power from power source 20 to heater 22 to heat the aerosol-generating article.

[0199] If the sensor 26 fails to detect the indicator element 74, it is assumed that the second housing 16 has been removed from the first housing 14. In this case, the sensor 26 may provide a signal to the controller 18 indicating that the second housing 16 has been removed from the first housing 14, and the controller 18 may prevent the supply of power to the heater 22.

[0200] A first end of the torsion spring 66 engages the spring holder 64 and a second end of the torsion spring 66 engages the cap 70. When a user rotates the cover element 42 from the closed position to the open position, the spring holder 64 rotates and loads the tension spring 66. When the user releases the cover element 42, the load of the tension spring 66 applies a rotational force to the spring holder 64, which urges the cover element 42 from the open position toward the closed position.

[0201] 32 is a cross-sectional view of an aerosol-generating article 80 for use with the aerosol-generating device 10. The aerosol-generating article 80 comprises an aerosol-forming substrate 82 in the form of a tobacco plug, a hollow acetate tube 84, a polymeric filter 86, a mouthpiece 88, and an outer wrapper 90. When the aerosol-generating article 80 is received in the cavity 32 of the aerosol-generating device 10, the heater 22 is received within the tobacco plug. During use, the heater 22 heats the tobacco plug to generate an aerosol.

Claims

1. An aerosol generating device, comprising: Housing and a recess for receiving an aerosol-generating article; an opening defined at least in part by the housing and positioned at an end of the cavity for inserting an aerosol-generating article into the cavity through the opening; a cover element arranged to move relative to the housing between a closed position in which the cover element at least partially covers the opening and an open position in which the opening is at least partially uncovered; a sensor arranged to provide an electrical signal indicative of a position of the cover element relative to the opening; an electric heater arranged to heat the aerosol-generating article when the aerosol-generating article is received in the cavity, the electric heater being arranged to extend around and around an outer surface of the aerosol-generating article received in the cavity; an indicator element disposed for movement relative to the sensor when the cover element moves between the closed and open positions, the electrical signal provided by the sensor being determined by a position of the indicator element relative to the sensor, the indicator element comprising a magnetic material, and the sensor comprising a Hall effect sensor; and a biasing mechanism arranged to bias the cover element away from the open position and towards the closed position, the biasing mechanism comprising a torsion spring; An aerosol generating device comprising:

2. The aerosol generating device of claim 1 , wherein operation of the electric heater depends on the electrical signal provided by the sensor.

3. 2. The aerosol generating device of claim 1, further comprising a controller and a power source, the controller being arranged to control the supply of power from the power source to the electric heater in response to a signal received from the sensor.

4. The aerosol generating device of claim 3, wherein the controller is arranged to supply power from the power source to the electric heater in accordance with a predetermined heating cycle only when the controller receives a signal from the sensor indicating that the cover element is in the open position.

5. 5. The aerosol generating device according to claim 2, wherein the electric heater comprises a resistance heating element or an induction heating element.

6. An aerosol generating device according to any preceding claim, wherein the indicator element is connected to the cover element, and optionally the indicator element is formed separately from the cover element and attached to the cover element.

7. 7. The aerosol generating device of claim 1, wherein the cover element is positioned such that when the cover element is in the closed position, the cover element covers at least 50 percent of the opening.

8. 8. The aerosol generating device of claim 1, wherein the cover element is positioned such that when the cover element is in the closed position, the cover element covers at least 95 percent of the opening.

9. 9. An aerosol generating device according to any preceding claim, wherein the cover element is positioned such that when the cover element is in the closed position, the cover element completely covers the opening.

10. 10. The aerosol generating device of claim 1, wherein the cover element is positioned such that when the cover element is in the open position, the cover element covers less than 5 percent of the opening.

11. An aerosol generating device according to any preceding claim, wherein the cover element is arranged so that the opening is not completely covered when the cover element is in the open position.

12. 12. An aerosol generating device according to any preceding claim, wherein the housing includes an end wall, and the opening extends through a first portion of the end wall.

13. 13. The aerosol generating device of claim 12, wherein the cover element is positioned such that the cover element overlies the second portion of the end wall when the cover element is in the open position.

14. 14. An aerosol generating device according to any preceding claim, wherein the aerosol generating device comprises a mechanical linkage, the mechanical linkage including the biasing mechanism.

15. An aerosol generating system comprising an aerosol generating device according to any one of claims 1 to 14 and an aerosol generating article, the aerosol generating article including an aerosol-forming substrate.

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