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CN-122003951-A - Dielectric heating aerosol generating device with resonant oscillator

CN122003951ACN 122003951 ACN122003951 ACN 122003951ACN-122003951-A

Abstract

The present invention proposes an aerosol-generating device for heating an aerosol-forming substrate in a dielectric manner. The device comprises a power supply device which provides a DC power supply voltage, and an oscillating circuit. The oscillating circuit comprises a switching unit and a feedback loop connected between an input and an output of the switching unit. The feedback loop includes a resonant circuit. The resonant circuit comprises two electrical contacts interconnected with an electrode arrangement forming a load capacitor CL. The load capacitor CL is configured to receive the aerosol-forming substrate for dielectric heating. In a heating operation, the feedback loop is configured to heat the aerosol-forming substrate received by the electrode arrangement such that the ratio between the peak voltage on the load capacitor CL and the DC supply voltage is at least 5, preferably at least 10, more preferably at least 15, even more preferably at least 20.

Inventors

  • O. Milonov

Assignees

  • 菲利普莫里斯生产公司

Dates

Publication Date
20260508
Application Date
20241004
Priority Date
20231005

Claims (17)

  1. 1. An aerosol-generating device comprising: A power supply device that supplies a DC power supply voltage, and An oscillating circuit, wherein the oscillating circuit comprises: Switch unit, and A feedback loop connected between the input and the output of the switching unit, the feedback loop comprising a resonant circuit comprising two electrical contacts interconnected with an electrode arrangement forming a load capacitor C L , the load capacitor C L being configured to receive an aerosol-forming substrate for dielectric heating, Wherein in a heating operation, the feedback loop is configured to heat the aerosol-forming substrate received by the electrode arrangement such that the ratio between the peak voltage on the load capacitor C L and the DC supply voltage is at least 5, preferably at least 10, more preferably at least 15, even more preferably at least 20.
  2. 2. An aerosol-generating device according to claim 1, wherein the ratio between the peak voltage on the load capacitor C L and the DC supply voltage is less than 100, preferably less than 50.
  3. 3. An aerosol-generating device according to claim 1 or 2, wherein the feedback loop is configured such that the peak voltage across the load capacitor C L exceeds 100V, preferably exceeds 150V, but is less than 500V, preferably less than 400V.
  4. 4. An aerosol-generating device according to any one of claims 1 to 3, wherein the electrode arrangement forming the load capacitor C L is fixedly interconnected to two contacts and the electrode arrangement is configured to removably receive the aerosol-forming substrate, or wherein the electrode arrangement forming the load capacitor C L is removably interconnected to the two contacts and the electrode arrangement comprises the aerosol-forming substrate.
  5. 5. An aerosol-generating device according to any of the preceding claims, wherein the resonant circuit of the feedback loop has an impedance in the range 500mOhm to 8Ohm, more preferably 800mOhm to 6Ohm, even more preferably 1Ohm to 4Ohm, even more preferably about 2 Ohm.
  6. 6. An aerosol-generating device according to any of the preceding claims, wherein the oscillating circuit further comprises a capacitor C 1 arranged in parallel with the switching unit, wherein the capacitance of the capacitor C 1 is larger than the maximum intrinsic capacitance of the switching unit at the operating frequency.
  7. 7. An aerosol-generating device according to any of the preceding claims, wherein the resonant circuit comprises two circuit branches, wherein a first of the two branches comprises the load capacitor C L .
  8. 8. An aerosol-generating device according to claim 7, wherein the first branch of the resonant circuit further comprises a first inductor L 1 connected to a first one of the two electrical contacts, and optionally wherein the first branch of the resonant circuit further comprises a second inductor L 2 connected to a second one of the two electrical contacts.
  9. 9. An aerosol-generating device according to claim 8, wherein the first inductor L 1 and the second inductor L 2 are distributed relative to each other such that a mutual inductance is generated between them.
  10. 10. An aerosol-generating device according to claim 9, wherein the first inductor L 1 and the second inductor L 2 are arranged to have a mutual inductance of between 50% and 60%.
  11. 11. An aerosol-generating device according to any of the preceding claims, wherein the feedback loop is operable to provide a phase shift of about 180 ° between an input and an output of the switching unit, and the switching unit is configured for inverting operation.
  12. 12. An aerosol-generating device according to any of the preceding claims, wherein the resonant circuit is arranged to provide a phase shift of at least 90 ° at an operating frequency and to act as an inductor.
  13. 13. An aerosol-generating device according to any of the preceding claims, wherein the feedback loop further comprises a capacitive element providing a 90 ° phase shift.
  14. 14. An aerosol-generating device according to any of claims 7 to 13, wherein the feedback loop further comprises a delay line connected between the first branch of the resonant circuit and the switching unit to provide a delay to define an operating frequency.
  15. 15. A system, comprising: an aerosol-generating device according to one of claims 1 to 14, and An aerosol-generating article comprising the aerosol-forming substrate.
  16. 16. A system, comprising: An aerosol-generating article comprising an aerosol-forming substrate, and An aerosol-generating device, the aerosol-generating device comprising: A power supply device that supplies a DC power supply voltage, and An oscillating circuit, wherein the oscillating circuit comprises: Switch unit, and A feedback loop connected between the input and the output of the switching unit, the feedback loop comprising a resonant circuit comprising two electrical contacts configured to interconnect with an electrode arrangement forming a load capacitor C L , the load capacitor C L being configured to receive an aerosol-forming substrate for dielectric heating, Wherein in a heating operation, the feedback loop is configured to heat the aerosol-forming substrate by the electrode arrangement such that the ratio between the peak voltage on the load capacitor C L and the DC supply voltage is at least 5, preferably at least 10, more preferably at least 15, even more preferably at least 20.
  17. 17. A system according to claim 16, wherein the electrode arrangement forms part of the aerosol-generating article.

Description

Dielectric heating aerosol generating device with resonant oscillator The present invention relates to an aerosol-generating device, and in particular to an aerosol-generating device configured to heat an aerosol-forming substrate by dielectric heating. The invention also relates to a system comprising the aerosol-generating device and an aerosol-generating article comprising an aerosol-forming substrate. Background Known electrically operated aerosol-generating systems typically heat the aerosol-forming substrate by one or more of conducting heat from the heating element to the aerosol-forming substrate, radiating heat from the heating element to the aerosol-forming substrate, or drawing heated air through the aerosol-forming substrate. Most commonly, heating is achieved by passing an electrical current through the resistive heating element, producing joule heating of the heating element. Induction heating systems have also been proposed in which joule heating occurs due to eddy currents induced in the susceptor heating element. One problem with these heating mechanisms is that they produce non-uniform heating of the aerosol-forming substrate. The portion of the aerosol-forming substrate closest to the heating element is heated faster or to a higher temperature than the portion of the aerosol-forming substrate further from the heating element. Systems have been proposed for heating aerosol-forming substrates in a dielectric manner, which advantageously provide uniform heating of the aerosol-forming substrate. However, known dielectric heating systems are less efficient than induction heating systems and require complex circuitry in order to achieve the necessary voltages and frequencies for dielectric heating of the aerosol-forming substrate. It is desirable to provide a system that heats the aerosol-forming substrate in a dielectric manner with greater efficiency while still being achievable in a compact or handheld system. Disclosure of Invention According to a first aspect, the present disclosure provides an aerosol-generating device for dielectrically heating an aerosol-forming substrate. The device comprises a power supply device which provides a DC power supply voltage, and an oscillating circuit. The oscillating circuit comprises a switching unit and a feedback loop connected between an input and an output of the switching unit. The feedback loop comprises a resonant circuit comprising two electrical contacts interconnected with an electrode arrangement forming a load capacitor C L. The load capacitor C L is configured to receive an aerosol-forming substrate for dielectric heating, wherein in a heating operation the feedback loop is configured to heat the aerosol-forming substrate received by the electrode arrangement such that the ratio between the peak voltage on the load capacitor C L and the DC supply voltage is at least 5, preferably at least 10, more preferably at least 15, even more preferably at least 20. The oscillating circuit allows for more efficient dielectric heating by maximizing losses in the load capacitor, because there is a resonant circuit comprising two electrical contacts configured to interconnect with the electrode arrangement forming the load capacitor C L, and because the feedback loop is configured such that there is a much higher peak AC voltage across the load capacitor compared to the DC supply voltage. The ratio between the peak voltage on the load capacitor C L and the DC supply voltage may be less than 100, preferably less than 50. The feedback loop may be configured such that the peak voltage on the load capacitor C L exceeds 50V, preferably exceeds 100V, but is less than 500V, preferably less than 400V. The electrode arrangement forming the load capacitor C L may be fixedly interconnected to the two electrical contacts, and the electrode arrangement may be configured to removably receive an aerosol-forming substrate. The electrode arrangement forming the load capacitor C L may be removably interconnected to two electrical contacts and the electrode arrangement comprises an aerosol-forming substrate. The DC supply voltage may be between 3V and 13V, preferably between 6V and 12V. The oscillation frequency of the oscillation circuit may be in an Ultra High Frequency (UHF) range. The dielectric loss in the load capacitor C L is slightly proportional to frequency, thus increasing heating efficiency in the UHF range. The oscillating circuit may be tuned to minimize switching losses and maximize heat dissipation via the load capacitor C L for frequencies in the range between 100MHz and 1.2GHz, preferably between 150MHz and 1GHz, more preferably between 200MHz and 900 MHz. These frequency ranges allow for the use of cheaper components and simple circuit designs. Furthermore, in these frequency ranges, the electric field strength is reduced, thereby reducing the risk of electrical breakdown, so that the matrix remains stable. The oscillating circuit may be tuned to direct p