WO2018210749A1

WO2018210749A1 - Feeding system with actuator for removing a blockage

Info

Publication number: WO2018210749A1
Application number: PCT/EP2018/062375
Authority: WO
Inventors: Jakob Grevenstein
Original assignee: Philip Morris Products S.A.
Priority date: 2017-05-15
Filing date: 2018-05-14
Publication date: 2018-11-22

Abstract

This invention relates to a feeding system with an actuator for removing blockage and a respective method. This invention proposes a feeding system comprising a supporting surface for conveying prismatic objects and at least one side wall adjacent to the supporting surface. The feeding system further comprises an actuator for ejecting objects from an area of the supporting surface and a sensor for detecting a conveying defect. A section of the side wall is movable, wherein this section is coupled with the actuator so that the section of the side wall can be moved by the actuator to eject objects from the supporting surface, if a conveying defect is detected by the sensor. The length of the movable section of the side wall is at least two times the diameter of an object. The supporting surface is, at least adjacent to the movable section of the side wall, inclined towards the side wall.

Description

FEEDING SYSTEM WITH ACTUATOR FOR REMOVING A BLOCKAGE

The present invention relates to a feeding system with an actuator for removing a blockage.

Aerosol-generating articles which heat but do not burn an aerosol-generating substance such as a tobacco compound may utilize a heat source which is fixed to one end of the aerosol-generating article and which is in direct or indirect contact with the aerosol- generating substance. These heat sources may comprise two components, a powder unit containing combustible powder in a cylindrical shape, and a heat conductive material, for example aluminium. Typically, the heat conductive material is in contact or close proximity with the powder unit and also with the aerosol-generating substance. The heat conductive material transfers the heat of the burning powder unit to the aerosol-generating substance while at the same time preventing combustion gas from the combustion of the powder unit from being transferred to the aerosol-generating substance. Typically, the heat conductive material covers one end of the powder unit. This makes the heat source asymmetrical.

The heat sources may be manufactured and stocked independently to the other elements of the aerosol-generating article, particularly independently of the aerosol- generating substance of the aerosol-generating article. In a production process, the heat sources are delivered by means of a feeder towards a combiner which combines the heat sources with the rest of the aerosol-generating article. The heat sources are conveyed by means of the feeder on a supporting surface towards the combiner. The flow of heat sources on the supporting surface towards the combiner could be discontinuous, particularly at the ramp up of the feeder. Generally, the heat sources are to be delivered to the combiner in an upright position with the heat conductive material on top. Particularly when the flow of heat sources is not continuous, singular heat sources can fall backwards or forwards on the supporting surface and then lie horizontally on the supporting surface. A conveying defect such as for example a jammed heat source may be the result of one or more heat sources being in a backward or forward position.

The object of the present invention is to remove a conveying defect such as a blockage of objects on the supporting surface of the feeding system.

Accordingly, a feeding system is provided comprising a supporting surface for conveying prismatic objects and at least one side wall adjacent to the supporting surface. The feeding system further comprises an actuator for ejecting objects from an area of the supporting surface and a sensor for detecting a conveying defect. A section of the side wall is movable, wherein this section is coupled with the actuator so that the section of the side wall can be moved by the actuator to eject objects from the supporting surface, if a conveying defect is detected by the sensor. The length of the movable section of the side wall is at least two times the diameter of a prismatic object.

By providing a side wall which is not only used for guiding the objects along the supporting surface and restricting the lateral movement of the objects on the supporting surface, but also to act as an ejecting surface, the reliability of the feeding system can be improved. In this regard, a conveying defect such as a blockage can be removed by removing objects from a relatively large area of the supporting surface in a single intervention in the area of a conveying defect by moving the movable section of the side wall. Since the actuator is provided for moving the whole section of the movable side wall, objects can be removed from a whole area of the supporting surface such that the removal of a conveying defect can be ensured without knowledge of the exact location of the defect and the type of defect. An air jet system may not be sufficiently powerful to remove such a conveying defect. However, the side wall can be utilized according to the invention for removing a substantial blockage.

The movable section is preferably configured to eject two objects. In other embodiments, the movable section is configured to eject at least two objects. When the movable section of the side wall is at least two times the diameter of an object, the movable section is configured to eject at least two objects. The size of the movable section may be configured such that at least two objects can be pushed off of the supporting surface by the movable section at the same time. The operating power of the movable section is sufficient for ejecting at least two objects at the same time. The length of the movable section is at least two times larger than the height of the movable section so that the movable section can eject at least two objects.

In one embodiment, the supporting surface of the feeding system is inclined such that the prismatic objects are conveyed over the supporting surface by gravitational force. The supporting surface may also be provided as a conventional conveying surface such as a conveyer belt or a chain conveyor. Also, the feeding system may be provided as a vibrating feeder, and the supporting surface may use vibration or gravity or a combination of vibration and gravity to convey the prismatic objects. The supporting surface may be made of plastic or metal. The supporting surface may be provided with a low-friction coating. The supporting surface defines a plane, in which the prismatic objects are conveyed.

In one embodiment, the side wall of the feeding system is provided as a solid vertical wall made of a hard material such as plastic or metal. Also, the side wall may be provided as a guide rail. The side wall may also be made of a flexible material such that the side wall can be elastically deformed. When the side wall is provided from a solid material, the movable section of the side wall is configured as a separate part of the side wall such that a, preferable elongate, section of the side wall can be moved at least partially over the adjacent supporting surface. If the side wall is provided from a flexible material, the movable section may be provided as an area of the continuous side wall, which may be deformed by the actuator so as to move this area of the side wall in the direction of the adjacent supporting surface.

In an alternative embodiment, the blockage including the supporting surface could be removed and replaced by a section of supporting surface, which is provided for this purpose. Such a redundant section could be employed instead of the blocked section until the blocked section is emptied of prismatic objects and ready to be used again. A swinging or sliding mechanism may be employed for exchanging the blocked section with the redundant clear section.

In one embodiment, the actuator is provided as a pneumatic means, which is configured to couple to the movable section of the side wall and to move the movable section of the side wall in the direction of the supporting surface adjacent to the movable section of the side wall. The actuator may also be configured as a hydraulic, electric or as a mechanical actuator. In one embodiment, the actuator is firmly attached to the movable section of the side wall. Alternatively, the actuator is configured to be coupleable and detachable to or from the movable section of the side wall, so that an actuator is provided for multiple movable sections of the side wall. In the latter case, the actuator is configured movable between the different movable sections of the side wall so that a single actuator is provided to couple to at least two different sections of the side wall and move these respective different sections of the side wall. Also, multiple actuators may be provided. In this case, multiple movable sections of the side wall may be provided, wherein each movable section of the side wall is firmly connected with an actuator so that each movable section of the side wall can be independently moved by the respective actuator. In one embodiment, a number of actuators are provided smaller than the number of movable sections of the side wall. In this case, the actuators are provided movable between different sections of the side wall, so that multiple sections of the side wall can be moved simultaneously by multiple actuators.

In one embodiment, the sensor is provided as a proximity sensor such as a proximity laser sensor. The sensor may be arranged directly above the supporting surface so as to measure the distance between the supporting surface and the sensor. If an object passes below the proximity sensor on the supporting surface, the sensor detects that an object is arranged below the proximity sensor. Also, different orientations of the objects may be detected by the sensor, if these different orientations result in a different distance between the object and the sensor. The proximity sensor may also be arranged adjacent to the supporting surface for measuring the presence of a prismatic object on the supporting surface. An optical sensor such as a camera may also be employed. The sensor may be configured as an optical barrier. Other sensors for detecting a conveying defect may also be used. For example, a sensor with electrical contacts may be provided for measuring an electric property of objects passing next to the sensor. For example, if different areas of the prismatic objects have different electrical properties such as different electrical resistances, such a sensor may detect the presence and the orientation of a passing object based upon the measured electrical property.

In one embodiment, the sensor detects a conveying defect, if an object in a specific orientation is detected by the sensor. Additionally or alternatively, the sensor may detect a conveying defect, if at least one object detected by the sensor is no longer moving along the surface of the supporting surface. Also, the sensor may detect a conveying defect, if the time between the passage of subsequent objects passing over the supporting surface exceeds a pre-determined threshold. For example, an average distance between two prismatic objects may be used together with a known conveying speed to calculate the average time between two prismatic objects in the direction of transport. The time after which a conveying defect is detected may be at least two times the average time between two prismatic objects. Also, the statistical temporal distribution of the prismatic objects may be determined and a conveying defect may be detected after a significant time passes between two objects, wherein the significant time could be calculated based upon the statistical temporal distribution of the prismatic objects. The statistical temporal distribution could be pre-determined or measured by a sensor, preferably by the sensor for detecting a conveying defect.

In some embodiments, the prismatic objects have a polygonal cross section, for example with three or more sides. In one embodiment, the cross section of the prismatic objects is oval or semi circular. In some embodiments, the prismatic objects have a cylindrical shape. In some embodiments, the prismatic objects have the shape of a right circular cylinder. In some embodiments, the prismatic objects have the shape of an elliptic cylinder, a parabolic cylinder, or a hyperbolic cylinder. In one preferred embodiment, the prismatic objects are provided as cylindrical objects. In some embodiments, the top faces of the prismatic objects are parallel to the bottom faces of the prismatic objects. In some embodiments, the side faces of the prismatic objects are parallel to each other. Preferably, the prismatic objects are identical.

In one embodiment, the prismatic objects are configured as cylindrical heat sources which are used in the manufacturing of aerosol-generating articles. Such heat sources comprise a powder unit containing combustible powder, which is compressed and delivered in a cylindrical shape. A carbon based powder may be utilized in the powder unit. Also, the heat source comprises a heat conductive material, for example metal such as aluminium. The heat conductive material is in contact with the powder unit. The heat conductive material is arranged at a top of the heat source, while the powder unit is arranged at a bottom of the heat source. The top as well as the bottom of the heat source are arranged perpendicular to the longitudinal axis of the heat source. The heat source has a cylindrical shape, wherein the length of the heat source is larger than the diameter of the heat source. The length of the heat source is measured along the longitudinal cylindrical axis of the heat source. The diameter of a prismatic object such as a heat source is between around 0.1 to 1 .5 millimeter, preferably 0.3 to 1 .0 millimeter, and more preferably 0.5 to 0.7 millimeter. The length or height of the prismatic object such as a heat source is around 0.5 to 2.0 millimeter, preferably 0.7 to 1 .5 millimeter, and more preferably 0.9 to 1 .1 millimeter.

In one embodiment, the prismatic objects are provided as heat sources, which should be conveyed in an upright position standing on the supporting surface. In this embodiment, the correct orientation is an orientation, in which the longitudinal axis of the heat sources should be perpendicular to the plane of the supporting surface. Furthermore, the heat conductive material is arranged on top of the heat sources, while the powder unit is arranged at the bottom of the heat sources in contact with the supporting surface.

During operation of the feeding system, particularly when starting the feeding system, prismatic objects which are conveyed on the supporting surface may have a misaligned orientation. Particularly, when the prismatic objects conveyed on the supporting surface do not touch each other and thereby support their upright position, the prismatic objects may fall onto their side surfaces. In other words, some of the prismatic objects may lie on their side surfaces on top of the supporting surface instead of standing upright on the supporting surface. Such misaligned prismatic objects may cause a blockage. When subsequent prismatic objects are conveyed into the area of blockage, conventional ejectors such as air jet ejectors may not have sufficient power to eject the misaligned objects from the supporting surface. Furthermore, depending upon the conveying speed, a blockage of multiple prismatic objects may happen very quickly. The present invention enables that a whole section of the supporting surface can be cleared from prismatic objects. By means of the movable section of the side wall, a whole section of the supporting surface can be cleared from prismatic objects efficiently.

According to one embodiment, the sensor is provided downstream of the movable section of the side wall. By providing the sensor downstream of the movable section of the side wall, the sensor is able to detect a conveying defect in the upstream section of the supporting surface adjacent to the movable side wall, if no prismatic object passes by the sensor by a predetermined time period. Preferably, a proximity sensor is used in this embodiment for detecting the presence of prismatic objects downstream of the movable side section of the side wall.

In one embodiment, at least in an area adjacent to the movable section of the side wall, the supporting surface is inclined towards the side wall. In this embodiment, the side wall is only provided on one side of the supporting surface, such that the prismatic objects can easily be ejected by the movable section of the side wall over the free side of the supporting surface. To prevent that objects fall from the supporting surface at the side of the supporting surface which is not equipped with a side wall during normal operation, the side wall is advantageously be inclined towards the side of the supporting surface which is equipped with a side wall. Thus, a secure conveying action on the supporting surface can be ensured while objects on top of the supporting surface can easily be ejected by the movable section of the side wall.

According to one embodiment, the movable section of the side wall is movable transversely to the direction of travel of the objects on the supporting surface. In this embodiment, the movable section is movable in a plane which is essentially parallel to a plane which is defined by the surface of the supporting surface. A safe ejection action can be ensured in this way while preventing a jam of the prismatic objects while ejecting the prismatic objects.

In one embodiment, the movable section of the side wall can be moved similar to a slider such that the movable section uniformly pushes the prismatic objects from the supporting surface. In a further embodiment, the movable section is partly pushed over the supporting surface such that the stream of prismatic objects is directed away from the supporting surface. In this embodiment, a downstream part of the movable section of the side wall is moved by the actuator over the supporting surface, while an upstream part of the movable section of the side wall essentially remains in the same position. Thus, the movable section is arranged transverse across the supporting surface by the actuator to remove prismatic objects from the supporting surface. This embodiment has the further advantage that prismatic objects which are conveyed to the area of the blockage are automatically also ejected by the movable section due to the arrangement of the section transversely across the supporting surface. In a further embodiment, the side wall is provided from a flexible material and the actuator pushes the material of the flexible side wall to remove the blockage. The actuator may be configured to push a section of the side wall that is sufficiently large to remove all prismatic objects which are part of the blockage.

The length of the side wall which is movable is long enough such that at least an objects lying on its side is savely ejected. Thus, the length of the movable section is at least the heigt of an object. Preferably, the length of the movable section is at least two times the diameter of a prismatic object to be conveyed such that multiple objects can be ejected. Preferable, the length of the movable section of the side wall is at least two times the length of a prismatic object. More preferable, the length of the movable section of the side wall is more than two times the diameter or length of a prismatic object.

The invention further relates to a method for conveying prismatic objects by means of a feeding system, wherein the method comprises the following steps:

(i) providing a supporting surface for conveying prismatic objects;

(ii) providing at least one side wall adjacent to the supporting surface, wherein at least a section of the side wall is movable;

(iii) providing an actuator for ejecting objects from an area of the supporting surface, wherein the actuator is coupled with the at least one movable section of the side wall;

(iv) providing a sensor for detecting a conveying defect;

(v) detecting, by the sensor, if a conveying defect has occurred; and

(vi) ejecting, by the actuator coupled to the movable section of the side wall, at least two objects from the supporting surface for removing the conveying defect.

In one embodiment, four sections of the side wall are provided as movable sections. Furthermore, two actuators are provided for coupling to the movable sections of the side wall and ejecting prismatic objects adjacent to the respective movable sections from the supporting surface. In this embodiment, the two actuators are configured to couple to the four movable sections of the side wall. For example, one ejector may be configured to couple to two of the movable sections, while the other actuator may be configured to couple to the other two movable sections. Alternatively, each of the actuators is configured to couple to each of the movable sections. By providing four movable sections of the side wall and two actuators, the versatility of the ejecting mechanism can be enhanced. In this regard, different sections of the supporting surface can be cleared. Furthermore, the area of the cleared supporting surface can be controlled by using one ejector and one movable section only or using two ejectors and two movable sections.

The invention will be further described, by way of example only, with reference to the accompanying drawings in which:

Fig. 1 : shows an illustrative top view and sectional view of the feeding system before an ejecting action; shows an illustrative top view and sectional view of the feeding system after an ejecting action;

shows an illustrative top view of a feeding system with a sensor arranged downstream; and

shows an exemplary cylindrical object.

In the left part of Fig. 1 , a top view of a feeding system according to the invention is depicted. Multiple prismatic objects 10 can be seen which are conveyed on top of a supporting surface 12. Adjacent to the supporting surface 12, a side wall 14 is provided.

On the side of the supporting surface 12 opposite to the side which is provided with a side wall 14, no side wall is provided such that the prismatic objects 10 can be ejected from the supporting surface 12 over this side of the supporting surface 12.

A portion of the side wall 14 is provided as a movable section 16. An actuator 18 is provided for moving the movable section 16 of the side wall in the direction of a blockage of prismatic objects 10.

The right part of Fig. 1 shows a sectional view of the feeding system. The surface of the supporting surface 12 is inclined towards the side wall 14 such that the prismatic objects 10 can be securely conveyed over the supporting surface 12 without falling from the supporting surface 12.

In Fig. 2, the feeding system is depicted after a removal of a blockage. In this regard, the left part of Fig. 2 shows a top view of the feeding system, in which the actuator 18 has pushed the movable section 16 of the side wall 14 over the supporting surface 12 so as to clear an area of the supporting surface 12 from prismatic objects 10. As can be seen in Figs. 1 and 2, one of the prismatic objects 10 has created a blockage such that subsequent prismatic objects 10 have been stopped by the misaligned cylindrical object 10. This blockage has been removed, in Fig. 2, by the movable section 16 of the side wall 14.

In the right part of Fig. 2, the removal of the blockage is depicted in a sectional view. The movable section 16 of the side wall 14 is pushed, by means of the actuator 18, over the surface of the supporting surface 12, such that the prismatic objects 10 are pushed from the supporting surface 12. The prismatic objects 10 can be reused, or, if they are damaged, be disposed.

In Fig. 3, a sensor 20 is depicted downstream of the movable section 16 of the side wall 14. The sensor 20 is provided as a laser proximity sensor for measuring the presence of a cylindrical object 10 downstream of the movable section 16 of the side wall 14. The distance D between the movable section 16 and the sensor 20 is chosen such that a blockage can securely be resolved by the movable section 16 in case the sensor detects such a blockage upstream of the sensor. To ensure that the blockage can be safely eliminated, the distance D should be less then V * T, wherein V is the conveying speed of the prismatic objects 10, and T is a predetermined time, in which the sensor detects a blockage upstream of the sensor. This time may be determined based on the statistical temporal distribution of the prismatic objects on the supporting surface. For example, the time T may be twice the average time between two prismatic objects. The length P of the movable section 16 of the side wall 14 should be more than

wherein E is the average distance between two prismatic objects 10, and H is the height of the prismatic objects 10. This value for the length P of the movable section 16 of the side wall 14 represents the length all blocked prismatic objects 10 could have achieve from the blockage initial point occurring at the distance D from the sensor 20 and going upstream, one stuck to the other, during the time T. To have a secure value, the prismatic objects 10 are supposed all lying horizontally. This assumption facilitates a secure clearing action of the supporting surface 12, since the diameter of the prismatic objects 10 is inferior to their height, so the highest possible distance regarding the dimensions of the prismatic objects 10 is taken.

Fig. 4 shows a heat source as an example of a cylindrical object 10. The heat source has an elongate cylindrical shape, wherein a heat conductive material 22 is arranged on top of the heat source, and a powder unit 24 is provided at the bottom part of the heat source. The heat sources are conveyed on top of the supporting surface 12, wherein the heat conductive material 22 is on top of the heat source, not contacting the supporting surface 12, and the powder unit 24 is in direct contact with the supporting surface 12.

Claims

1 . Feeding system, comprising:

- a supporting surface for prismatic objects;

- at least one side wall adjacent to the supporting surface;

- an actuator for ejecting objects from an area of the supporting surface; and

- a sensor for detecting a conveying defect,

wherein at least a section of the side wall is movable and coupled with the actuator so that the section of the side wall can be moved by the actuator to eject objects from the supporting surface, if a conveying defect is detected by the sensor, and wherein the length of the movable section of the side wall is at least two times the diameter of an object, wherein the supporting surface is, at least adjacent to the movable section of the side wall, inclined towards the side wall.

2. A feeding system according to claim 1 , wherein the sensor is provided downstream of the movable section of the side wall, and wherein the sensor is configured to detect a blockage, if no objects are detected by the sensor for a predetermined time period downstream of the movable section of the side wall.

3. A feeding system according to claim 2, wherein the predetermined time period is based upon the average time period between subsequent objects being detected by the sensor.

4. A feeding system according to one of the preceding claims, wherein the actuator is configured as a mechanism for moving the movable section of the side wall back and forth with respect to the supporting surface.

5. A feeding system according to claim 4, wherein the movable section of the side wall is movable, by means of the actuator, transversely with respect to the supporting surface.

6. A feeding system according to one of the preceding claims, wherein the sensor is provided as a proximity sensor, preferably as a laser proximity sensor.

7. A feeding system according to one of the preceding claims, wherein multiple sections of the side wall are provided movable, and wherein each of the movable sections of the side wall can be coupled to the actuator, which is configured movable between the multiple movable sections of the side wall, such that objects can be ejected from the supporting surface adjacent to a movable section of the side wall, if a conveying defect is detected by the sensor adjacent to this movable section of the side wall.

8. A feeding system according to one of the preceding claims, wherein multiple sections of the side wall are provided movable, and wherein each of the movable sections of the side wall can be coupled with a separate actuator, such that objects can be ejected from the supporting surface adjacent to a movable section of the side wall, if a conveying defect is detected by the sensor adjacent to this movable section of the side wall.

9. A feeding system according to one of the preceding claims, wherein the prismatic objects have a diameter which is smaller than the height of the prismatic objects.

10. A feeding system according to one of the preceding claims, wherein the prismatic objects have diameter of 0.1 to 1 .5 millimeter, preferably 0.3 to 1 .0 millimeter, and more preferably 0.5 to 0.7 millimeter and a height of between 0.5 to 2.0 millimeter, preferably 0.7 to 1 .5 millimeter, and more preferably 0.9 to 1 .1 millimeter.

1 1 . Method for conveying prismatic objects by means of a feeding system, wherein the method comprises the following steps:

(i) providing a supporting surface for conveying prismatic objects;

(ϋ) providing at least one side wall adjacent to the supporting surface, wherein at least a section of the side wall is movable, wherein the length of the movable section of the side wall is at least two times the length of an object;

providing an actuator for ejecting objects from an area of the supporting surface, wherein the actuator is coupled with the at least one movable section of the side wall;

(iv) providing a sensor for detecting a conveying defect;

(v) providing the supporting surface, at least adjacent to the movable section of the side wall, inclined towards the side wall;

(vi) detecting, by the sensor, if a conveying defect has occurred; and

(νϋ) ejecting, by the actuator coupled to the movable section of the side wall, at least two objects from the supporting surface for removing the conveying defect.

12. A method according to claim 1 1 , wherein the sensor measures the time period between the detection of subsequent objects for determining if a conveying defect has

13. A method according to one of claims 1 1 or 12, wherein multiple sections of the side wall are provided movable, and wherein each of the sections can be coupled to the actuator, which is configured movable between the multiple movable sections of the side wall, and wherein the method further comprises the steps of:

- in step (vi), detecting, by the sensor, in which area of the supporting surface a conveying defect has occurred; and

- in step (vii), before ejecting objects from the supporting surface for removing the conveying defect, moving the actuator to the movable sections of the side wall adjacent to the conveying defect and coupling the actuator with this movable section of the side wall such that objects can be ejected from the supporting surface adjacent to this movable section of the side wall, if a conveying defect is detected by the sensor adjacent to this movable section of the side wall.

14. A method according to one of claims 1 1 or 12, wherein multiple sections of the side wall are provided movable, and wherein each of the sections can be coupled with a separate actuator, and wherein the method further comprises the steps of:

- in step (vii), actuating the actuator coupled with the movable section of the side wall adjacent to the conveying defect such that objects can be ejected from the supporting surface adjacent to this movable section of the side wall, if a conveying defect is detected by the sensor adjacent to this movable section of the side wall.