GB2173388A

GB2173388A - Apparatus for manufacturing tobacco filter incorporating a granular additive

Info

Publication number: GB2173388A
Application number: GB08604556A
Authority: GB
Inventors: Ichiro Hirose
Original assignee: Japan Tobacco Inc
Current assignee: Japan Tobacco Inc
Priority date: 1985-04-11
Filing date: 1986-02-25
Publication date: 1986-10-15
Also published as: GB8604556D0; GB2173388B; JPS61234771A; JPH0242468B2; DE3606206A1

Abstract

The apparatus includes in a preferred embodiment a conveyance mechanism 1 for conveying a belt- like tobacco filter material 2 continuously along a predetermined conveyance path; a mask member 26 disposed above the filter material being conveyed, the mask member 26 partitioning an upper surface of the filter material 2 into first areas in which said upper surface is partially exposed to the exterior and second areas in which said upper surface is partially covered from the exterior, alternately in a moving direction of the filter material; and an additive feeder 29 for sprinkling a granular additive toward the upper surface of the filter material 2 located under the mask member 26. <IMAGE>

Description

SPECIFICATION Apparatus for manufacturing tobacco filter BACKGROUND OF THE INVENTION The Present invention relates to an apparatus for manufacturing a cigarette filter and more particularly to an apparatus for manufacturing a tobacco filter with a granular additive added into the filter.

Various granular additives have heretofore been added into tobacco filters for improving the adsorbability and absorbability of the filters. Usually such additives are each added into a certain portion in a filter material so as to be enclosed with the filter material, or a filter material is divided into two filter halves and a granular additive is added so as to be held between those filter halves.

Of the above two kinds of tobacco filters, in the former there is the possibility that during transport or smoking the additive added into the filter material will move and be exposed to a smoking end of the tobacco filter and get into the smoker's mouth, In the former, moreover, since the additive is concentrated on one part of the filter material, it is impossible to ensure a large area of contact of the additive with the tobacco smoke passing through the filter material and consequently the adsorbing and absorbing properties of the additive are impaired.

On the other hand, in the latter case, its structure wherein the additive is held between the two filter halves, is effective for preventing the movement of the additive, but is disadvantageous in that the tobacco filter manufacturing process becomes complicated, resulting in increase of the cost. In the latter case, moreover, it is impossible like the former case to ensure a large area of contact of the additive with the tobacco smoke passing through the filter material with the result that the adsorbing and absorbing properties of the additive are impaired.

SUMMARY OF THE INVENTION The present invention has been accomplished in view of the circumstances mentioned above and it is the object thereof to provide a tobacco filter manufacturing apparatus which can manufacture tobacco filters easily and which can improve the adsorbing and absorbing properties of additives.

The present invention provides a tobacco filter manufacturing apparatus comprising: porous conveyor means for conveying a length of belt-like tobacco filter material longitudinally in a predetermined direction; a mask member disposed in facing relation to said porous conveyor means to hold said length of belt-like tobacco filter material therebetween, said mask member being adapted for synchronized travel along with said porous conveyor means in said predetermined direction, said mask member having a plurality of slits therein extending laterally with respect to said length of filter material; suction means provided on an opposite side of the porous conveyor means with respect to said filter material; and means for supplying granular additive into said slits such that said granular additive adheres onto the tobacco filter material in laterally extending separate areas thereof through said slits due to suction from said suction means.

BRIEF DESCRIPTION OF THE DRA WINGS Figs. 1 to 9 illustrate an embodiment of the present invention, of which: Fig. 1 is a sectional view of an additive distributing and feeding device; Fig. 2 is a schematic view of the whole of a tobacco filter manufacturing apparatus; Fig. 3 is a sectional view taken along line Ill-Ill in Fig. 1; Fig. 4 is a side view of an additive feeder, partly broken away; Fig. 5 is a sectional view taken along line V V in Fig. 4; Fig. 6 is a top view of a filter material with an additive adhered thereto; Fig. 7 is a sectional view of Fig. 6; Fig. 8 is a transverse sectional view of a tobacco filter manufactured; and Fig. 9 is a longitudinal sectional view of Fig.

8.

Figs. 10 and 11 illustrate modifications of the present invention, of which: Fig. 10 is a sectional view of a part of a mask ring; and Fig. 11 is a sectional view of an additive distributing and feeding device.

DESCRIPTION OF A PREFERRED EMBODIMENT An embodiment of the present invention will be described hereinunder with reference to Figs. 1 to 9.

A brief explanation will first be made about the entirety of a tobacco filter manufacturing apparatus which is illustrated in Fig. 2. The reference numeral 1 in Fig. 2 denotes a first conveyance mechanism for conveying length of a beltlike filter material 2 to the left in the figure. The filter material 2 is formed from a fibrous cellulose acetate. But the material is not limited thereto. It may be formed from paper, woolen yarns or a fibrous rough hemp.

Disposed above the filter material 2 is an additive distributing and feeding device 3 which supplies an additive at predetermined intervals in a moving direction of the filter material 2.

Ahead of the additive distributing and feeding device 3 in the moving direction of the filter material are disposed first and second molding members 4 and 5 for molding the belt-like filter material 2. The first and second molding members 4 and 5 are both tubular members which are in the shape of a funnel. The beltlike filter material 2 is formed into a round rod while passing through the first and second molding members 4 and 5.

Ahead of the first and second molding members 4 and 5 in the moving direction of the filter material is disposed a second conveyance mechanism 6 for conveying the filter material 2 thus formed into a round rod toward a cutter 7 which is positioned in front of the conveyance mechanism 6. For example, the second conveyance mechanism 6 is constituted by an endless conveyor belt 10 stretched between a driving roller 8 of a large diameter and a driven roller 9 of a small diameter. The numeral 11 in Fig. 2 denotes a tension roller which imparts a predetermined tension to the conveyor belt 10.

Between the second conveyance mechanism 6 and the additive distributing and feeding device 3 is disposed a wrapping paper roller 13 with a filter material wrapping paper 12 wound thereon. The wrapping paper 12 delivered from the roller 13 is conducted into the second molding member 5 through a roller 14, whereby it- is wound round the outer peripheral surface of the filter material 2 which has been formed into a round rod by the first molding member 4. Further, a paster 15 is disposed midway of the conveyance path of the wrapping paper 12 extending to the second molding member 5. The paster 15 pastes one face ofthe wrapping paper 12, whereby the wrapping paper 12 is securely wound and pasted onto the outer peripheral surface of the filter material 2.The round rod-like filter material 2 thus wrapped in the wrapping paper 12 is conveyed to the cutter 7 through a heater 16 and a cooler 17 by means of the second conveyance mechanism 6 as previously noted and is cut into a predetermined size by the cutter 7.

Mechanisms and devices located after the additive distributing and feeding device 3 are of the same structures as in the prior art and may be modified in practicing the present invention.

The first conveyance mechanism 1 and the additive distributing and feeding device 3 according to the present invention will be explained below with reference to Figs. 3 to 5.

The first conveyance mechanism 1 is composed of a driving roller 20 of a large diameter, driven rollers 21 and 22 of a small diameter, and a porous conveyor belt 23 stretched over the rollers 20, 21 and 22 for conveying the filter material 2. The conveyor belt 23 is a porous belt though not shown, which permits a free permeation of air. The numeral 24 in Fig. 1 represent guide rollers for guiding the movement of the conveyor belt 23. The driving roller 20, driven rollers 21, 22 and guide rollers 24 are rotatably supported by a frame 25 shown in Fig. 3. The driving roller 20 is rotated in the direction of arrow A in Fig. 1 by means of a drive source (not shown) which is synchronized with the second conveyance mechanism 6.

The additive distributing and feeding device 3 disposed above the first conveyance mechanism 1 is provided with a mask ring 26. The mask ring 26 is constituted by a hollow flat cylinder whose one side face is open. To- a central part of a closed face of the mask ring 26 is connected a rotating shaft 27 which is connected to a drive source (not shown) synchronized with the second conveyance mechanism 6.

In the outer peripheral surface of the mask ring 26 are formed a number of laterally extending slits 28 at equal intervals in a circumferential direction as shown in Figs. 1 and 3.

The slits 28 are each of an elongated shape extending axially of the mask ring 26 and two neighboring slits are, in cross section, are- spaced apart from each other in an inner surface of the annular structure. Further, a rim 26a is formed in the open side of the mask ring 26 to project radially inwardly from the periphery thereof.

The outer peripheral surface of the mask ring 26 is in contact with the conveyor belt 23 through the filter material 2 which is conveyed by the first conveyance mechanism 1, as shown in Fig. 1. As a result, the-upper surface of the filter material 2 is partitioned into first areas in which it is exposed to the exterior through the slits 28 and second areas in which it is covered from the exterior. The first and second areas are defined alternately in the moving direction of the filter material.

As the mask ring 26 of annular structure comes into rolling contact with the conveyor belt 23 of the first conveyance mechanism 1 through the filter material 2, a predetermined tension is imparted to the belt 23. In Fig. 1, however, for convenience of drawing the figure, the outer peripheral surface of the mask ring 26 and the filter material 2 and conveyor belt 23 are shown in spaced relation to each other.

The mask ring 26 is rotated in the direction of arrow B in Fig. 1 and its peripheral speed is set at the same speed as the travelling speed of the conveyor belt 23, whereby a smooth conveyance of the filter material 2 can be ensured and the first and second areas can be defined continuously on the upper surface of the filter material 2. The rotating speed of the mask ring 26 is set so that the slits 28 and the cutter 7 are synchronized with each other.

Within the mask ring 26 is disposed an additive feeder 29 on an upstream side of the rotating shaft 27. As shown in detail in Figs.

3 to 5, the additive feeder 29 is provided with a metallic feed roller 30 which is disposed near the inner peripheral surface of the mask ring 26. The feed roller 30 has a roller shaft 31 which is supported at a free end or lower end of a support arm 32 rotatably through bearings 33. An upper end of the support arm 32 extends upward over the outer periphery of the mask ring 26 and is fixed to the frame 25.

A sprocket 34 is attached to a fore end of the roller shaft 31 and a chain 37 is stretched between the sprocket 34 and a sprocket 36 which is attached to a fore end of a drive shaft 35. The drive shaft 35 extends in parallel with the rotating shaft 27 of the- mask ring 26 and is rotated synchronously by the same drive source as that for the mask ring.

Above-the feed roller 30 is disposed an additive feed hopper 38. The hopper 38 is in the form of a box having upper and lower open ends, the lower end opening being closed with the feed roller 30. In the feed hopper 38 is stored an additive X such as granular active carbon, silica gel or ion exchange resin. A hopper opening 39 is formed in an end face 38a on a downstream side of the feed roller 30 with respect to the rotation thereof. The degree of opening of the hopper opening 39 can be adjusted by an adjusting plate 40 which is attached to the end face 38a of the feed hopper 38 with adjusting bolts 41 and washers 42. In the adjusting plate 40 are formed bolt insertion holes 43 by vertically extending slots, whereby a vertical position of the adjusting plate 40, namely, the degree of opening of the hopper opening 39, can be adjusted.

Moreover, within the mask ring 26 is disposed a scraper 44 which is positioned just under the rotating shaft 27 and which is in contact with the inner peripheral surface of the mask ring 26, and also disposed is an air nozzle 45 which is positioned closer to the additive feeder 29 than the scraper 44. The air nozzle 45 can eject a compressed air toward the inner peripheral surface of the mask ring 26. The scraper 44 and the air nozzle 45 are supported by support means (not shown) from the open end side of the mask ring 26.

Further, in the area of the first conveyance mechanism 1 surrounded with the conveyor belt 23 is disposed an air suction member 46 whose side facing the conveyor belt 23 is open along the same belt. The air suction member 46 is connected to a vacuum pump (not shown) through a suction pipe 47.

The operation of the additive distributing and feeding device 3 constructed as above will be explained below.

When the filter material 2 is conveyed by the first conveyance mechanism 1 and reaches the position cf the mask ring 26, its upper surface is partitioned into the first areas in which it is exposed to the exterior through the slits 28 and the second areas in which it is covered with the outer peripheral surface of the mask ring 26, alternateiy in the moving direction of the filter material. If the feed roller 30 of the additive feeder 29 is rotated in this state, the additive X is fed to the exterior from the hopper opening 39 of the feed hopper 38 with rotation of the feed roller 30, as shown in Fig. 5.The additive X thus fed out is sprinkled over the inner peripheral surface of the mask ring 26 by virtue of a free falling thereof, whereby it is adhered to only the first area of the filter material 2 in which area the outer surface of the filter material is exposed to the exterior. In this case, with the compressed air ejected from the air nozzle 45 the additive X can be conducted effectively into the slits 28 of the mask ring 26 and the portion thereof staying on the inner peripheral surface of the mask ring 26 can be surely conducted into the slits 28 by the scraper 44.

Consequently, when the filter material 2 is fed out from the mask ring 26, there are formed adhered portions Y of the additive X on the upper surface of the filter material 2 at equal intervals in the moving direction of the filter material and at a uniform thickness, as shown in Figs. 6 and 7. Since air is sucked through the porous conveyor belt 23 by the air Suction member 46, the additive X adhered to the upper surface of the filter material 2 is held in place securely and is prevented from moving on the said upperzsurface.

Thereafter, the filter material 2 with the additive X adhered thereto is formed into a round rod as previously noted and the wrapping paper 12 is wound round the outer peripheral surface thereof, then the rod-like filter material is cut into a predetermined size.

On the upper surface of the filter material 2 are formed the adhered portions Y of the additive X at equal intervals in the moving direction of the filter material as previously described, so in the subsequent rounding of the belt-like filter material 2 into a round rod, the additive X can be distributed uniformly in the round rod-like filter material 2 as shown in Figs. 8 and 9. Consequently, the area of contact of the additive X with the tobacco smoke passing through the filter material 2 can be taken large, thus permitting a great improvement in adsorbing and absorbing properties of the additive X.

Moreover, when the filter material 2 is formed into a round rod, the additive X is held between wrinkles of the filter material, so there is no fear of an accidental movement of the additive X during tobacco transport or smoking. Besides, when cutting the round rodlike filter material 2, the filter material can be clearly partitioned into areas 2a which contain the additive X and areas 2b which do not contain the additive X, as shown in Fig. 9, so it is possible to surely prevent the additive from entering the smoker's mouth during smoking.

Further, according to the above embodiment, the feed roller 30 in the additive feeder 29 is rotated in synchronism with the rotation of the mask ring 26, so with increase of the rotational speed of the mask ring 26, the amount of the additive X supplied from the additive feeder 29 becomes larger. Therefore, the additive adhered portions Y formed on the upper surface of the filter material 2 can be.

rendered almost constant in thickness regardless of the rotatidnal speed of the mask ring 26. As a result, it is possible to increase the tobacco filter manufacturing speed so that it is suitable for a high volume production, and make the quality of tobacco filters produced uniform.

The present invention is not limited to-the above embodiment. Modifications of the invention are illustrated in rigs. 10 and 11. Fig.

10 shows a part of the mask ring 26, in which partition walls 28a which define slits 28 are formed triangularly in section such that two neighboring slits adjoin by way of a ridge in an inner surface of the annular- structure to prevent the additive X from staying on the inner peripheral surface of the mask ring 26.

This structure permits omission of the scraper 44.

Referring to Fig. 11, the additive distributing and feeding device 3 is further provided in a synchronized manner with a third conveyance mechanism 48 for conveying an additional belt-like filter material 2c separately downstream of the first conveyance mechanism 1.

The filter materila 2c is superposed on the upper surface of the filter material 2 with the additive X adhered thereto, as shown in Fig.

11. By so doing, the movement of the additive X adhered to the filter material 2 can be surely prevented in the following step.

Further, though not shown, in place of the mask ring 26 there may be used a mask belt which is driven in synchronism with the conveyor belt 23 and which. has slits 28, and in place of the additive feeder 29 using the feedroller 30 there may be used an additive feeder which utilizes vibrations of a vibration plate to supply the additive X from the feed hopper 38.

According to the present invention, as set forth hereinabove, the additive can be distributed uniformly over a predetermined area in the tobacco filter, so it is possible to improve the adsorbing and absorbing properties of the additive; besides, an accidiental movement of the additive in the tobacco filter can be surely prevented. Thus, there is no fear of the additive entering the smoker's mouth during smoking.

Further, since the tobacco filter manufactured according to the apparatus cf the present invention is substantially constituted by a single filter material, it is easy to manufacture.

Besides, it is suitable for a continuous production.

Claims

1. A tobacco filter manufacturing apparatus comprising porous conveyor means for conveying a length of beltlike tobacco filter material longitudinally in a predetermined direction; a mask member disposed in facing relation to said porous conveyor means to hold said length of belt-like tobacco filter material therebetween, said mask member being adapted for synchronized travel along with said porous conveyor means in said predetermined direction, said mask member having a plurality of slits therein extending laterally with respect to said length of filter material; suction means provided on an opposite side of the porous conveyor means with respect to said filter material; and means for supplying granular additive into saimslits such that said granular additive adheres onto the tobacco filter material in laterally extending separate areas thereof through said slits-due to suction from said suction means.

2. A-tobacco filter manufacturing apparatus according to claim 1, wherein said mask member includes a mask ring having an annular structure and adapted for rotation about an axis thereof.

3. A tobacco filter manufacturing apparatus according to claim 2, wherein said granular additive supplying means is disposed within said annular structure.

4. A tobacco filter manufacturing apparatus according to claim 3, wherein said granular additive supplying means includes an additive feed hopper positioned on an upstream side of said axis of the mask ring, a scraper positioned under said axis in contact with the mask ring end an air nozzle positioned between said additive feed hopper and said scraper.

5. A tobacco filter manufacturing apparatus according to claim 4, wherein two neighboring slits are spaced apart from each other in an inner surface of the annular structure.

6. A tobacco filter manufacturing apparatus according to claim 2, wherein two neighboring slits adjoin by way of a ridge therebetween in an inner surface of the annular structure.

7. A tobacco filter manufacturing apparatus according to claim 1, further including additional conveyor means provided downstream of the mask member to convey an additional length of belt-like filter material in said predetermined direction in a synchronized manner such that said additional length of filter material holds the granular additive in cooperation with said length of belt-like material therebetween.

8. A tobacco filter manufacturing apparatus substantially as hereinbefore described with reference to Figures 1 to 9 of the accompanying drawings.

9. A tobacco filter manufacturing apparatus modified substantially as hereinbefore described with reference to Figures 10 to 11 of the accompanying drawings.