Patent Application
20120060446
The invention relates to a dosing method as well as to a dosing device, in particular for dosing snus or the like, wherein a portion of tobacco is filled into a dosing chamber of a dosing device and wherein the portion of tobacco is blown out of the dosing chamber by means of blow-out air.
Such dosing methods or dosing devices, respectively, for carrying them out, are well known from the state of the art and are used on a regular basis for dosing or portioning tobacco, respectively. For instance, volumetric dosing with fixed or adjustable volumes is also common for dosing or portioning, respectively, of smaller quantities of tobacco for oral tobaccos, such as snus. In the case of the known methods, dosing chambers, into which a quantity of tobacco is filled in each case for portioning it, are embodied in a rotatable dosing plate. The rotatable dosing plate can be moved by means of a grinding disk, which closes the dosing chamber, such that a portion of tobacco falls downward out of the dosing chamber when a dosing chamber overlaps with an opening in the grinding disk. In the alternative, it is also possible to close the dosing chamber by means of lids or sliders. It is further known to blow out or accelerate, respectively, the portion of tobacco from the dosing chambers by means of a blast of air. In addition to the afore-described alternative of emptying the dosing chamber downward, the dosing chamber can also be emptied upward by means of a blast of air. This method is used when a volume of the dosing chamber is to be adjustable. For this purpose, a die or piston is moved into the dosing chamber from a lower side of the dosing plate, so as to adjust the desired volume of the dosing chamber. The respective portion of tobacco can then be blown out via a compressed air line, which ends in the dosing chamber.
In the case of the two types of dosing, problems arise during the dosing process due to the comparatively small dosing quantities. For instance, tobacco adheres in the dosing chamber and in lines, whereby the desired portion size is portioned so as to be too small or inaccurate or clogging occurs, respectively.
The instant invention is thus based on the object of proposing a dosing method and a dosing device for dosing oral tobacco, by means of which an accurate dosing of a portion of tobacco is made possible without constant adhesion or clogging, respectively.
This object is solved by means of a method comprising the features of claim 1 and a device comprising the features of claim 7.
In the case of the dosing method according to the invention, in particular for dosing snus or the like, a portion of tobacco is filled into a dosing chamber of a dosing device, wherein the portion of tobacco is blown out of the dosing chamber by means of blow-out air, and wherein water vapor is added to the blow-out air.
The blow-out air is directed onto the portion of tobacco, which is located in the dosing chamber, as a blast of air from an upper side or lower side of the dosing chamber, so that the portion of tobacco is blown out of the dosing chamber and is conveyed into a conveying channel for further transporting the portion of tobacco. The blow-out air is emitted as a blast of air by means of a valve, which is connected to a source of compressed air, wherein the water vapor is added to the blow-out air following the valve. The blow-out air, which is provided with vapor, provides for a substantially complete blow-out of the portion of tobacco located in the dosing chamber or for a cleaning of the dosing chamber, respectively, without tobacco residues adhering to an inner wall of the dosing chamber or remaining, respectively. The method according to the invention thus ensures a complete discharge of the portion of tobacco from the dosing chamber and thus an accurate dosing or dispensing, respectively, of a desired portion size.
In an advantageous embodiment of the method, hot steam can be used as water vapor. Hot steam can encompass a temperature of above 300° C. and is thus also suitable for killing germs, among others. A use of hot steam can thus serve to disinfect the corresponding dosing device or the tobacco processed with it, respectively, during normal operation. A complete discharge of the tobacco from the dosing chamber can also be promoted further by means of the hot steam.
In a further advantageous embodiment of the method, a vacuum can be applied to the dosing chamber in response to the filling. For instance, it can be ensured that the dosing chamber is completely filled with tobacco, without the embodiment of unwanted large air gaps in the tobacco located in the dosing chamber during the filling, for example. This can be the case, for example, when the tobacco is filled into the dosing chamber by means of a so-called inlet box and is compressed due to the dead weight of the tobacco located in the inlet box. In comparison, a compression of the tobacco by means of a vacuum can always ensure an even compression of the tobacco, independent on the quantity of tobacco located in the inlet box.
To clean the dosing chamber, the blow-out air and/or the water vapor can be blown into the empty dosing chamber. In particular, it is advantageous when hot steam is used for cleaning. For instance, all of the dosing chambers, feed lines and discharging conveying channels can be disinfected and cleaned by means of an “idling” of the dosing device without tobacco.
After blowing the portion of tobacco out of the dosing chamber, water vapor can further be added to the portion of tobacco. For example, after the portion of tobacco has escaped from the dosing chamber, the water vapor can be introduced into a conveying channel, which is provided for the portion of tobacco. The water vapor promotes a further transport of the tobacco, without the appearance of unwanted adhesions of tobacco in the conveying channel. In the event that hot steam is used as water vapor, a disinfection of the conveying channel can also take place during normal operation.
To ensure a substantially sterile operation of the dosing device, the blow-out air can be filtered in a sterile manner. For instance, provision can be made between the compressed air source and the valve, which is provided for emitting the blow-out air, for one or a plurality of filters for the sterile or almost sterile filtering of the blow-out air. It can thus be ensured that unwanted germs cannot reach into the dosing device or into the tobacco, which is to be processed, respectively, via the blow-out air.
The dosing device according to the invention, in particular for dosing snus and the like, consists of a dosing plate, in which at least one through hole is arranged, which forms a dosing chamber, of a closing device, which serves to close an opening side of the through hole, and of a filling device, which serves to fill the dosing chamber with a portion of tobacco, and of a blow-out device, which serves to blow the portion of tobacco out of the dosing chamber by means of blow-out air, wherein water vapor can be added to the blow-out air by means of the blow-out device. By adding water vapor to or by mixing water vapor with the blow-out air, respectively, the afore-mentioned advantages, which result from the method according to the invention, can be attained.
To be able to add a vacuum to the dosing chamber for an improved dosing, the dosing plate can encompass an air-permeable wall. The wall can consist of a porous material or can encompass a plurality of small boreholes, through which the air can escape from the dosing chamber. For example, the porous material can be a sintered material. For instance, provision can also be made in the dosing plate in the area of the dosing chamber for a ring channel, which serves to discharge the air, which is sucked off through the respective wall.
The closing device can also encompass an air-permeable wall. The closing device can be embodied as a plate or a grinding disk, respectively, as a die, a lid or a slider in the area of a lower side of the dosing plate. Air for forming a vacuum in the dosing chamber can be sucked off via the air-permeable wall, which can also again be embodied from a porous material or as a wall comprising small boreholes. When the portion of tobacco is to be blown out via the closing device, thus when the dosing chamber is to be emptied upward, blow-out air can also be blown into the dosing chamber via the air-permeable wall of the closing device.
This type of blow-out is advantageous in particular when a size of the dosing chamber is embodied so as to be adjustable. For instance, a blow-out can always be carried out independent of an adjusted volume of the dosing chamber, without requiring an extensive reconstruction of the dosing device.
The size of the dosing chamber can be adjusted particularly easily when the closing device encompasses a die, which is arranged within the through hole, so as to be capable of being moved relative thereto. The die or piston, respectively, can be adapted to a diameter of the through hole, so that it completely closes the through hole and so that an up or down movement, respectively, of the die relative to the dosing plate causes a volume change of the dosing chamber. A simple correction or change of a portion size can also be carried out during the normal operation of the dosing device.
Adding water vapor, in particular hot steam, to the blow-out air, can inevitably lead to a temperature increase of the components of the dosing device, which are in contact with the blow-out air. To avoid a possibly unwanted temperature increase in this area, the blow-out device can encompass a thermally insulated blow-out air supply. Such a thermal insulation can be sensible, among others, when the blow-out air reaches the dosing chamber via a die of the closing device. For instance, it can be avoided that the die or the entire closing device, respectively, heats up unduly. The blow-out air supply can be embodied, for example, as a thermally insulated pipeline, which leads into an area of an air-permeable inner wall of the closing device.
To further promote a complete discharge of tobacco from the dosing chamber, the dosing chamber can encompass a conical inner wall, at least in sections. A cone, which widens in conveying direction of the portion of tobacco, can ensure that the portion of tobacco disengages easily from the dosing chamber and does not get jammed between opposite wall areas of the dosing chamber. A conical form of the inner wall can be embodied along a common length of the dosing chamber but also only in sections.
It is further advantageous when at least one inner wall or also all of the inner walls of the dosing chambers is or are formed from polytetrafluorethylene (PTFE), respectively. The PTFE can be applied to the inner wall like a nonstick coating. The material PTFE or a material mixture on the basis of PTFE, respectively, can effectively prevent an adhesion of tobacco in the dosing chamber.
The inner wall can be composed of a bushing, which consists of a plastic material, for example. Through this, the inner wall can be produced and replaced easily. For instance, the PTFE can be embodied in the form of a ring-shaped, sintered bushing, which is inserted into the through hole, which embodies the dosing chamber. The ring-shaped bushing can then also embody an air-permeable wall. The bushing can further encompass a collar, which projects beyond the dosing plate and which forms a contact surface for bearing on the rotary disk. A friction between the dosing plate and the rotary disk can be avoided through this. In the event that the collar has worn out, the bushing can be replaced easily.
A conveying channel, the inner wall of which is formed from polytetrafluorethylene, can be arranged downstream in conveying direction of the dosing chamber. The inner wall of the conveying channel can consequently be comprised of a nonstick coating, which consists of PTFE. For instance, it can be avoided that the tobacco, which is blown out of the dosing chamber, adheres to the inner wall of the conveying channel.
The dosing chamber can also be embodied by a plurality of through holes. That is, the dosing chamber then consists of a plurality of through holes, which together form the dosing chamber. A complete blow-out of tobacco can be promoted even further through this. In particular, this is a result of a more favorable distribution of an air pressure across a cross section of the dosing chamber, which is embodied in this manner.
To be able to accelerate a dosing or portioning, respectively, by means of the dosing device or a portioning by means of the dosing device, respectively, or to be able to process large quantities of tobacco at the same time, respectively, a row of through holes, which in each case embody a dosing chamber, can be embodied in the dosing plate. The through holes can be arranged in a row for simultaneously carrying out an operating step and/or in a row for carrying out a sequence of operating steps. For example, the dosing plate can be embodied as a so-called rotary disk comprising a plurality of through holes, which are located on different diameters.
Further advantageous embodiments of the device result from the feature descriptions of the subclaims, which are dependent on method claim 1.
The invention will be defined in more detail below with reference to the enclosed drawings:
The dosing chambers 17, 18 and 19 are in each case covered on a lower side 26 of the dosing plate 12 by means of the grinding disk 13 and are thus closed. An outlet opening 27, which, as is illustrated herein in an exemplary manner, provides for a dispensing of tobacco 28 out of the dosing chamber 17 in a conveying direction, which is identified by means of an arrow 29, is embodied in the grinding disk 13. The respective dosing chambers 17, 18 and 19 are positioned in the direction of the arrow 11 above the outlet opening by means of the relative movement of the dosing plate 12.
The filling device 14 comprises a so-called inlet box 30, which is partially filled with loose tobacco 28 and which is arranged above the dosing plate 12. Provision is further made for a height-adjustable sensor 31, which monitors a fill level of the inlet box 30 and which thus provides for an adjustment of a compression of the tobacco 28 in the dosing chambers 17, 18 and 19 by a dead weight of the tobacco 28. Due to the fact that the inlet box 30 is arranged rigidly relative to the grinding disk 13 and covers an upper side 32 of the dosing plate 12, a filling of the dosing chambers 17, 18 and 19, as is shown herein using the example of the dosing chamber 19, is carried out by means of a movement thereof below the inlet box 30 such that the tobacco 28 can flow into the dosing chamber 19 due to dead weight. A complete and compact filling is further supported in that a porous wall 33 is embodied on the grinding disk 13 below the inlet box 30 and the dosing chamber 19, which is illustrated here in this area, to which a defined vacuum can be applied. For this purpose, provision is further made for a channel 34, which covers the porous wall 33, as well as for a vacuum line 35, which is connected to the channel 34.
After the dosing chamber 19 illustrated herein has been filled with tobacco 28 and thus contains a portion 36, the dosing chamber 19 is moved in the direction of the arrow by means of a movement of the dosing plate 12 to the position of the dosing chamber 17 illustrated herein above the outlet opening 27. Below the outlet opening 27, a funnel-shaped conveying channel 37 is arranged on the grinding disk 13 for transferring the tobacco 28. Above the outlet opening 27, a funnel-shaped blow-out channel 38 is rigidly arranged relative to the outlet opening 27 on the upper side 32 of the dosing plate 12. A valve 41 comprising a compressed air line 42 of a compressed air source 43 is arranged on an end 40 of the blow-out channel 38, which faces away from the funnel end 39. Filters 44 for disinfecting the blow-out air are coupled into the compressed air line 42. By means of temporarily opening the valve 41, a blast of air, which leads to an ejection of the tobacco 28 out of the filled dosing chamber 17, is effected in the direction of the arrow 45 onto the upper side 32 of the dosing plate 12. In addition to this, the blow-out device 15 comprises a water vapor source 46, from which water vapor, which is not illustrated herein, is introduced into the blow-out channel 38 via a water vapor channel 47 and to which blow-out air, which is also not visible herein, is added. Provision can optionally be made on the funnel end 39 for a further valve 48, by means of which the blow-out channel 38 can be closed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2010 040 499.3 | Sep 2010 | DE | national |
