WO2023065333A1

WO2023065333A1 - System and method for assembly of a heater module for an aerosol generating device

Info

Publication number: WO2023065333A1
Application number: PCT/CN2021/125831
Authority: WO
Inventors: Zhibin Gao
Original assignee: Philip Morris Products S.A.
Priority date: 2021-10-22
Filing date: 2021-10-22
Publication date: 2023-04-27

Abstract

There is provided a method of assembly of a heater module for an aerosol generating device, the heater module comprising a tubular heater (6) and top and bottom casing parts (4,2) arranged concentrically relative to the tubular heater, the method comprising: providing an assembly fixture (30) comprising first and second portions (32,36) coupled together; sliding the tubular heater (6) onto first portion of the assembly fixture (32) from a first end of the assembly fixture, so that the tubular heater forms a sleeve around the first portion of the assembly fixture, until the tubular heater abuts a stop surface formed by the second portion of the assembly fixture (36); sliding the bottom casing part (2) onto the first portion of the assembly fixture from the first end; uncoupling the second portion of the assembly fixture from the first portion of the assembly fixture; sliding the top casing part (4) onto the first portion of the assembly fixture from a second end, opposite the first end; fixing the top casing part to the bottom casing part to form the heater module; and removing the first portion of assembly fixture from the heater module.

Description

SYSTEM AND METHOD FOR ASSEMBLY OF A HEATER MODULE FOR AN AEROSOL GENERATING DEVICE

The present disclosure relates to a system and method for the assembly in high volume production of a heater module for a heated aerosol generating device, and specifically to assembly of a heating module in which the heater is positioned externally of the substrate that it heats to generate a vapour or aerosol.

One problem with the design and assembly of a heater module for an aerosol generating device is how to efficiently align and assemble the components of a heater module to allow for high volume manufacturing. It is an object of this disclosure to address that problem.

In a first aspect of the disclosure there is provided a method of assembly of a heater module for an aerosol generating device, the heater module comprising a tubular heater and a top casing part and a bottom casing part arranged concentrically relative to the tubular heater, the method comprising:

providing an assembly fixture comprising a first portion and a second portion coupled together;sliding the tubular heater onto the first portion of the assembly fixture from a first end of the assembly fixture, so that the tubular heater forms a sleeve around the first portion of the assembly fixture, until the tubular heater abuts a stop surface formed by the second portion of the assembly fixture;

sliding the bottom casing part onto the first portion of the assembly fixture from the first end;

uncoupling the second portion of the assembly fixture from the first portion of the assembly fixture;

sliding the top casing part onto the first portion of the assembly fixture from a second end, opposite the first end;

fixing the top casing part to the bottom casing part to form the heater module; and removing the first portion of assembly fixture from the heater module.

Advantageously, the heater module comprises a generally tubular heater holder. The method may comprise sliding the heater holder onto the first portion of the assembly fixture from the first end prior to sliding the bottom casing part onto the first portion of the assembly fixture from the first end.

Advantageously, the heater module may comprise relatively few components that are assembled on the assembly fixture. The tubular heater may comprise several components that are preassembled into a single piece before being slid onto the assembly fixture. For example, the heater may comprise a heating element that is a resistive track on a flexible substrate that is formed into a tube. The heater may also comprise a thermal insulating layer, formed from an aerogel, wrapped around the heating element. Any necessary seals may also be preassembled to other parts, such as the top casing part and the bottom casing part, before being assembled on the assembly fixture.

The tubular heater may comprise a plurality of heater pins for connecting the heater to a power supply. The heater pins may pass through openings in the bottom casing part as the bottom casing part is slid onto the first portion of the assembly fixture from the first end. The method may comprise sealing one or more of the openings in the bottom casing part for the heater pins using glue or a sealant, such as silicone. This prevents vapour and liquids from reaching the electronic circuitry connected to the heater.

As an initial step, the method may comprise coupling the first and second portions of the heater assembly fixture together.

The first portion of the assembly fixture may comprise one or more keying features configured to engage corresponding features on the bottom casing part and top casing part. A keying feature is a feature of the shape of the first portion of the assembly fixture that breaks the rotational symmetry of the first portion of the assembly fixture about the longitudinal. The keying features limit the top casing part and the bottom casing part to sliding on the first assembly fixture in one or a limited number of orientations. The keying features may include one or more longitudinally extending channels. The keying features may include one or more longitudinally extending ribs or protrusions. The keying features may prevent components from sliding along the first portion of the assembly fixture unless they are in a correct orientation. The keying features allows the top and bottom casing parts to be easily and correctly aligned with the heater and any other components of the heater module interior to the outer casing of the heater module. The heater holder may also have one or more keying features that interact with the first portion of the assembly fixture or with the top or bottom casing parts to orient the components of the heater module relative to each another. The keying features may also provide additional stop surfaces that limit the extend that one or more components can travel in the longitudinal direction along the first portion of the assembly fixture.

Fixing the top casing part to the bottom casing part may comprises using one or more screw fastenings or bolts. With the top casing part and bottom casing part securely fixed to one another, the heater module can be made robust and efficient to handle when assembling it to other components of an aerosol generating device.

In another aspect, there is provided an assembly fixture for use in assembly of a heater module of an aerosol generating device, the assembly fixture comprising: a first fixture portion and a second fixture portion, the first fixture portion being generally cylindrical and having longitudinal axis and a diameter transverse to the longitudinal axis, the second fixture portion being releasably coupled to the first fixture portion and being generally tubular, the second fixture portion forming a sleeve around at least part of the first fixture portion when coupled to the first fixture portion and comprising a stop surface extending transverse to the longitudinal axis, in use, the stop surface configured to engage a heater module component sleeved onto the first fixture portion.

An assembly fixture in accordance with this aspect allows for fast, accurate and efficient assembly of a tubular heater module for an aerosol generating device.

The first fixture portion may comprise one or more keying features configured to engage corresponding features on a component of the heater module as the component is slid onto the first fixture portion along the longitudinal axis. This allows for accurate and rapid alignment of the components of the heater module.

The keying features may comprise a channel extending parallel to the longitudinal axis. The channel may extend across a diameter of the first fixture portion. The channel may correctly orient the heater holder or the bottom casing part. One end of channel may provide a stop surface that limits the longitudinal position of heater holder or the bottom casing part.

The first fixture portion may be coupled to the second fixture portion by a removable pin. This allows the first fixture portion to be easily coupled and uncoupled from the second fixture portion. It also allows the first and second fixture portions to be reused. The removable pin may extend orthogonal to the longitudinal axis. This prevents relative movement of the first and second heater portions along the longitudinal axis. Alternatively, the first fixture portion may be coupled to the second fixture portion more permanently. In that case the second fixture portion may be uncouple from the first fixture portion by breaking the second fixture portion off of the first fixture portion.

The first fixture portion may have a first section at a first end of the assembly fixture and a second section adjacent to the first section, wherein the first section has a smaller diameter than the second section. This may be advantageous for interacting with different components of the heater module. For example, the bottom casing part may comprise an airflow passage that has a smaller diameter that the heater and the heater holder in order to provide a desired resistance to draw. The change in diameter may also provide a stop surface for an aerosol generating article received in the device. The first fixture portion may be shaped to correspond to the dimensions of the internal airflow passage of the heater module to ensure that all pasts are concentrically located on the assembly fixture.

In another aspect, there is provided a heater module for an aerosol generating device, the heater module comprising:

a tubular heater;

a heater holder; and

an outer casing , the outer casing comprising a bottom casing part and a top casing part fixed to the bottom casing part;

wherein the heater module has a longitudinal axis and an interior airflow channel extending along the longitudinal axis, and wherein the heater holder, the bottom casing part and the top casing part each are generally tubular and arranged along the longitudinal axis, and wherein the tubular heater and the heater holder are enclosed within the outer casing.

The tubular heater may be an electrical resistance heater.

The heater module may comprise a thermal insulating structure arranged around the tubular heater and within the outer casing. The thermal insulating structure may comprise an aerogel. The thermal insulating structure may comprise an insulating tape. The thermal insulating structure may comprise a vacuum tube.

The top casing part may be fixed to the bottom casing part using one or more screw fastenings.

The bottom casing part may comprise a plurality of openings through which electrical connection pins from the heater pass, and wherein each of the opening is sealed with glue or a sealant.

In a still further aspect there is provided an aerosol generating device comprising a heater module as described above. The aerosol generating device may be a heated aerosol generating device. The aerosol generating device may be configured to heat an aerosol generating article inserted into the heater module. The aerosol generating device may be configured to heat a tobacco-based aerosol-forming substrate.

Examples in accordance with the aspects of the disclosure will be now be described with reference to the accompany drawings, in which:

Figure 1 is a schematic cross-sectional view showing the interior of an aerosol-generating device 100 and an aerosol-generating article 200 received within the aerosol-generating device 100;

Figure 2 is an exploded view of a heater module for use in a system as shown in Figure 1;

Figure 3 shows an assembly fixture used in the assembly of a heater module as shown in Figure 2;

Figure 4 illustrates how the components of the heater module fit around the assembly fixture;

Figure 5 illustrates steps in an assembly process of a heater module; and

Figure 6 illustrates final steps in the assembly process.

Figure 1 is a schematic cross-sectional view showing the interior of an aerosol-generating device 100 and an aerosol-generating article 200 received within the aerosol-generating device 100. Together, the aerosol-generating device 100 and aerosol-generating article 200 form an aerosol-generating system. In Figure 1, the aerosol-generating device 100 is shown in a simplified manner. In particular, the elements of the aerosol-generating device 100 are not drawn to scale. Furthermore, elements that are not relevant for the understanding of the aerosol-generating device 100 have been omitted.

The aerosol-generating device 100 comprises a housing 102 containing a tubular heater 6, a power supply 103 and control circuitry 105. In Figure 1, the bottom heater casing part 2, heater mount 8 and top heater casing part 4 are shown. The power supply 103 is a battery and, in this example, it is a rechargeable lithium ion battery. The control circuitry 105 is connected to both the power supply 103 and the heating element and controls the supply of electrical energy from the power supply 103 to the heater to regulate the temperature of the heater.

The housing 102 comprises an opening 104 at a proximal or mouth end of the aerosol-generating device 100 through which an aerosol-generating article 200 is received. The opening 104 is connected to the opening 12 in the heater module 1, through which aerosol exits the heater module 1. However, it will be appreciated that aerosol largely exits the heater module 1 and the aerosol-generating device 100 via the aerosol-generating article 200. The housing 102 further comprises an air inlet 106 at a distal end of the aerosol-generating device 100. The air inlet 106 is connected to the air inlet arranged at a distal end of the first tubular section 2b of the bottom casing part 2. The first tubular section 2b delivers air from the air inlet 106 to the aerosol-generating article.

The aerosol-generating article 200 comprises an end plug 202, an aerosol-forming substrate 204, a hollow tube 206, and a mouthpiece filter 208. Each of the aforementioned components of the aerosol-generating article 100 is a substantially cylindrical element, each having substantially the same diameter. The components are arranged sequentially in abutting coaxial alignment and are circumscribed by an outer paper wrapper 210 to form a cylindrical rod. The aerosol-forming substrate 204 is a tobacco rod or plug comprising a gathered sheet of crimped homogenised tobacco material circumscribed by a wrapper (not shown) . The crimped sheet of homogenised tobacco material comprises glycerine as an aerosol-former. The end plug 202 and mouthpiece filter 208 are formed from cellulose acetate fibres.

A distal end of the aerosol-generating article 200 is inserted into the aerosol-generating device 100 via the opening 104 in the housing 102 and pushed into the aerosol-generating device 100 until it engages a stop (not shown in Figure 1) arranged on the heater mount 8, at which point it is fully inserted. The stop helps to correctly locate the aerosol-forming substrate 204 within the heater so that the heater can heat the aerosol-forming substrate 204 to form an aerosol.

The aerosol-generating device 100 may further comprise: a sensor (not shown) for detecting the presence of the aerosol-generating article 200; a user interface (not shown) such as a button for activating the heater; and a display or indicator (not shown) for presenting information to a user, for example, remaining battery power, heating status and error messages.

In use, a user inserts an aerosol-generating article 200 into the aerosol-generating device 100, as shown in Figure 1. The user then starts a heating cycle by activating the aerosol-generating device 100, for example, by pressing a switch to turn the device on. In response, the control circuitry 105 controls a supply of electrical power from the power supply 103 to the heater to heat the heater. During a heating cycle, the heater is heated to a predefined temperature, or to a range of predefined temperatures according to a temperature profile. A heating cycle may last for around 6 minutes. The heat from the heater 6 is transferred to the aerosol-forming substrate 204 which releases volatile compounds from the aerosol-forming substrate 204. The volatile compounds form an aerosol within an aerosolisation chamber formed by the hollow tube 206. During a heating cycle, the user places the mouthpiece filter 208 of the aerosol-generating article 200 between the lips of their mouth and takes a puff or inhales on the mouthpiece filter 208. The generated aerosol is then drawn through the mouthpiece filter 102 into the mouth of the user.

Figure 2 is an exploded view of a heater module for use in a system as shown in Figure 1. The heater module comprises outer casing comprising of a top heater casing part 4 and a bottom heater casing part 2. Within the outer casing is a heater 6, which comprises heater tracks on a flexible heater substrate. Aerogel insulation 10 and high temperature resistant tape 12 surround the heater. The heater is mounted on heater holder 8. The heater module also includes sealing rings 14, 16, 22 and 24. The top heater casing part is fixed to the bottom heater casing part using screws 18.Electrical pins from the heater 6 extend out through openings in the bottom casing part 2. Those openings are sealed with glue 20.

An advantage of the heater module is that, while the top heater casing part includes and protects inside the heater 6, the bottom heater casing part provides an elongated channel along which an air flow path is created whenever the consumer draws a puff on the consumable after final assembly in a device (see Figure 1) . Another advantage of the proposed solution is that the heater module can be used as a standalone module to be plug into any kind of different device design, the only constraint being the minimum length of the device which basically corresponds to the length of the heater module itself.

Figure 3 shows an assembly fixture used in the assembly of a heater module as shown in Figure 2. The assembly fixture 30 comprises a first assembly fixture portion 32 and a second assembly fixture portion 36. The first assembly fixture portion 32 and a second assembly fixture portion 36 are coupled together by a pin 38.

The assembly fixture is used to mount the components of the heater module during an assembly process. Figure 4 illustrates how the components of the heater module fit around the first assembly fixture portion 32. It can be seen the first assembly fixture portion fits within the central passage of the heater module components.

Figure 5 illustrates steps in an assembly process of a heater module using the assembly fixture 30. In step 1 the heater 6 and the insulation (represented by the S/Stube) is slid onto the first fixture portion 32 until it reaches the stop surface provided by the second fixture portion 36 (step 2) . Next the heater holder 8 is inserted on the first fixture portion 32 with the right orientation thanks to the keying features on the first assembly fixture portion (step 3-4) . The heater holder part has openings/channels to let the heater electrical connection pins pass through (step 5) . Next the bottom heater casing part 2 is assembled on the first assembly fixture portion (step 6) . The bottom heater casing part has also special openings/channels to let the electrical connection pins from the heater pass through it (step 7) .

The second fixture assembly part 36 is then detached from the first fixture assembly part (step 8) . The top heater casing part 4 is then sleeved on the other end of the first assembly fixture portion to allow the completion of the heater module assembly (step 9) . The insertion of top heater casing part while the first assembly fixture portion is still inside the heater module assembly allows for proper orientation of the screws 18 or any other locking mechanism that is used to join the two casings of the heater module (step 10) permanently and strongly.

Figure 6 illustrates the final steps in the assembly process. Steps 11-14 show a screwing station where the screwing action is performed easily thanks to the pre-existing alignment of the top and bottom heater casing parts. Step 15 is the application of glue to the holes on the bottom casing part through which the electrical connection pins pass.

Figures 5 and 6 do not show the very final step, after the heater module is released from the screwing jig, in which the first assembly fixture portion is removed from the heater module final assembly by simply pulling it from the heater assembly.

Claims

A method of assembly of a heater module for an aerosol generating device, the heater module comprising a tubular heater and top and bottom casing parts arranged concentrically relative to the tubular heater, the method comprising:

providing an assembly fixture comprising first and second portions coupled together;

sliding the tubular heater onto the first portion of the assembly fixture from a first end of the assembly fixture, so that the tubular heater forms a sleeve around the first portion of the assembly fixture, until the tubular heater abuts a stop surface formed by the second portion of the assembly fixture;

sliding the bottom casing part onto the first portion of the assembly fixture from the first end;

uncoupling the second portion of the assembly fixture from the first portion of the assembly fixture;

sliding the top casing part onto the first portion of the assembly fixture from a second end, opposite the first end;

fixing the top casing part to the bottom casing part to form the heater module; and

removing the first portion of assembly fixture from the heater module.
A method according to claim 1, wherein the heater module comprises a generally tubular heater holder, and wherein the method comprises sliding the heater holder onto the first portion of the assembly fixture from the first end prior to sliding the bottom casing part onto the first portion of the assembly fixture from the first end.
A method according to claim 1 or 2, wherein the tubular heater comprises a plurality of heater pins for connecting the heater to a power supply, wherein the heater pins pass through the bottom casing part as the bottom casing part is slid onto the first portion of the assembly fixture from the first end.
A method according to claim 3, comprising sealing one or more openings in the bottom casing part for the heater pins using glue or a sealant.
A method according to any one of the preceding claims, wherein the first portion of the assembly fixture comprises one or more keying features configured to engage corresponding features on the bottom casing part and top casing part, and optionally the heater holder, to orient the components of the heater module relative to each another.
A method according to any one of the preceding claims, wherein fixing the top casing part to the bottom casing part comprises using fixing screws or bolts.
An assembly fixture for use in assembly of a heater module of an aerosol generating device, the assembly fixture comprising:

a first fixture portion and a second fixture portion, the first fixture portion being generally cylindrical and having longitudinal axis and a diameter transverse to the longitudinal axis, the second fixture portion being releasably coupled to the first fixture portion and being generally tubular, the second fixture portion forming a sleeve around at least part of the first fixture portion when coupled to the first fixture portion and comprising a stop surface extending transverse to the longitudinal axis, in use, the stop surface configured to engage a heater module component sleeved onto the first fixture portion.
An assembly fixture according to claim 7, wherein the first fixture portion comprises one or more keying features configured to engage corresponding features on a component of the heater module as the component is slid onto the first fixture portion along the longitudinal axis.
An assembly according to claim 8, wherein the keying features comprise a channel extending parallel to the longitudinal axis.
An assembly according to claim 9, wherein the channel extends across a diameter of the first fixture portion.
An assembly fixture according to any one of claims 7 to 10, wherein the first fixture portion is coupled to the second fixture portion by a removable pin.
An assembly fixture according to claim 1, wherein the removable pin extends orthogonal to the longitudinal axis.
An assembly fixture according to any one of claims 7 to 12, wherein the first fixture portion has a first section at a first end of the assembly fixture and a second section adjacent to the first section, wherein the first section has a smaller diameter to the section.
A heater module for an aerosol generating device, the heater module comprising:

a tubular heater;

a heater holder; and

an outer casing, the outer casing comprising a bottom casing part and a top casing part fixed to the bottom casing part;

wherein the heater module has a longitudinal axis and an interior airflow channel extending along the longitudinal axis, and wherein the heater holder, the bottom casing part and the top casing part are each generally tubular and arranged along the longitudinal axis, and wherein the tubular heater and the heater holder are enclosed within the outer casing.
A heater module according to claim 14, wherein the tubular heater is an electrical resistance heater.
A heater module according to claim 14 or 15, comprising a thermal insulating structure arranged around the tubular heater and within the outer casing.
A heater module according to claim 14, 15 or 16, wherein the top casing part is fixed to the bottom casing part using one or more screw fastenings.
A heater module according to any one of claims 14 to 17, wherein the bottom casing part comprising a plurality of openings through which electrical connection pins from the heater pass, and wherein each of the opening is sealed with glue or a sealant.
An aerosol generating device comprising a heater module according to any one of claims 14 to 18.
An aerosol generating device according to claim 19, wherein the aerosol generating device is a heated smoking device.
An aerosol generating device according to claim 19 or 20 configured to heat a smoking article inserted into the heater module.