Heating assembly for an aerosol generating system

• US 9,674,894 B2
• Filed: 12/17/2013
• Issued: 06/06/2017
• Est. Priority Date: 12/28/2012
• Status: Active Grant

• Current Assignee: Philip Morris Products SA (Philip Morris Limited)
• Original Assignee: Philip Morris Products SA (Philip Morris Limited)
• Inventors: Fernando, Felix, Greim, Olivier, Schneider, Jean-Claude, Plojoux, Julien
• Primary Examiner(s): NGUYEN, PHU HOANG
• Application Number:
  US14/414,791
• Publication Number:
  US 20150163859A1
• Time in Patent Office: 1,267 Days
• Field of Search: None
• CPC Class Codes: A24F 40/20 Devices using solid inhalable precursors
• CPC Class Codes: A24F 40/46 Shape or structure of electric heating means
• CPC Class Codes: A24F 40/70 Manufacture
• CPC Class Codes: H05B 1/0244 Heating of fluids H05B1/0247 takes precedence
• CPC Class Codes: H05B 2203/021 Heaters specially adapted for heating liquids
• CPC Class Codes: H05B 3/0014 Devices wherein the heating current flows through particular resistances
• CPC Class Codes: Y10T 29/49083 Heater type

Abstract

A heating assembly for heating an aerosol-forming substrate is provided, including: a heater including an electrically resistive heating element and a heater substrate; and a heater mount coupled to the heater; wherein the heating element includes a first portion and a second portion configured such that, when an electrical current is passed through the heating element, the first portion is heated to a higher temperature than the second portion as a result of the electrical current; and wherein the heater mount surrounds the second portion of the heating element.

Claims

1. An aerosol-generating device, comprising:

a housing; and

a heating assembly comprising;

a heater comprising an electrically resistive heating element and a heater substrate; and

a heater mount coupled to the heater,

wherein the heating element comprises a first portion and a second portion configured such that, when an electrical current is passed through the heating element, the first portion is heated to a higher temperature than the second portion,

wherein the first portion of the heating element is positioned on a heating area of the heater substrate and the second portion of the heating element is positioned on a holding area of the heater substrate,

wherein the heater mount is fixed to and surrounds the holding area of the heater substrate, and

wherein the heater mount supports and secures the heater to the housing, an electrical power supply is connected to the heating element, and a control element is configured to control the supply of power from the power supply to the heating element.

2. The aerosol-generating device according to claim 1, wherein the housing defines a cavity surrounding the first portion of the heating element, the cavity being configured to receive an aerosol-forming article containing an aerosol forming substrate.

3. The aerosol-generating device according to claim 1, wherein the device is a handheld smoking device.

4. The aerosol-generating device according to claim 1, wherein the heater mount comprises a polymeric material.

5. The aerosol-generating device according to claim 1, wherein the first portion of the heating element is formed from a first material and the second portion of the heating element is formed from a second material, and wherein the first material has a greater electrical resistivity coefficient than the second material.

6. The aerosol-generating device according to claim 1, wherein the second portion of the heating element comprises two sections, each of the two sections being separately connected to the first portion of the heating element to define an electrical flow path from one section of the second portion to the first portion to another section of the second portion.

7. The aerosol-generating device according to claim 1, wherein the heating element comprises a third portion configured for electrical connection to a power supply, and wherein the third portion is positioned on an opposite side of the heater mount to the first portion of the heating element.

8. The aerosol-generating device according to claim 7, wherein the third portion is formed from a different material than the first and second portions.

9. The aerosol-generating device according to claim 1, wherein the first portion of the heating element is spaced from the heater mount.

10. The aerosol-generating device according to claim 1, wherein under normal operating conditions, when the first portion of the heating element is at a temperature of between 300 degrees centigrade and 550 degrees centigrade, at points of contact with the heater mount the second portion is at a temperature of less than 200 degrees centigrade.

11. The aerosol-generating device according to claim 1, wherein the first portion has a greater temperature coefficient of resistance than the second portion.

12. The aerosol-generating device according to claim 1, wherein if a maximum temperature of the first portion is T₁, an ambient temperature is T₀, and a temperature of the second portion of the heater element in contact with the heater mount is T₂, then:

(T₁-T₀)/(T₂-T₀)>

2.

13. The aerosol-generating device according to claim 1, wherein the heater substrate comprises a planar surface on which the heating element is positioned and a tapered end configured to allow for insertion into an aerosol-forming substrate.