GB2077569A

GB2077569A - Pneumatic ejector device for cigarette rods

Info

Publication number: GB2077569A
Application number: GB8113934A
Authority: GB
Original assignee: SASIB SpA
Current assignee: SASIB SpA
Priority date: 1980-05-09
Filing date: 1981-05-07
Publication date: 1981-12-23
Also published as: FR2484794B1; IT8015185V0; FR2484794A1; DE3118296A1; GB2077569B

Abstract

A pneumatic ejector device is provided for expelling when required cigarette rod lengths from the through duct of a detector unit in which the weight of tobacco filter per unit length of a continuous cigarette rod is sensed. The ejector device comprises an annular pneumatic ejector nozzle located at the inlet of the through duct of the detector unit. The nozzle is fed from an air feeding line, which is adapted to be temporarily connected, through a controllable intercepting means, with a source of air at a relatively high pressure, whereby an air jet is blown from the nozzle, strong enough for expelling from the said through duct of the detector unit and from the adjoining outlet duct, any broken-off cigarette rod lengths which remain therein, owing to incorrect manual insertion of a cigarette rod or accidental stopping of the cigarette-making machine. <IMAGE>

Description

SPECIFICATION Pneumatic Ejector Device For Cigarettes In cigarette-making machines, the operation of sensing continuously the weight per unit length, or specific weight, of the tobacco filler of a cigarette rod being produced, provides the standard for automati cally adjusting the said specific weight to the best constant value on which mainly depends the quality of the cigarette "draught", and therefore the liking of the cigarette by a smoker.

Such a continuous sensing of the tobacco filler specific weight is usually effected during the travel ofthe cigarette rod from the drierthat dries the glued portion of its tubular paper wrapper, to the cutter that cuts the cigarette rod into cigarette lengths.

It is known that for the said sensing operation use is made of detector units with a through duct in which the specific weight of the tobacco filler is sensed, and through which the cigarette rod is caused to travel from the said drier to the said cutter.

The present invention relates particularly, but in a non-limiting way, to those detector units in which radioactive materials are used for sensing the specific weight of the tobacco filler of a cigarette rod.

The cigarette rod moving into the said through duct of the detector unit has been just passed under the drier for drying the glue which sticks togetherthe superposed edges of the paper wrapper wound round its tobacco filler, so that it is still warm and wet, and therefore is has the tendency to promote the forming of condensate water on the inner, cold surface of said detector unit through duct. Besides wetting the paper of the cigarette rod, this conden sate water will also create an obstacle to the running of the cigarette rod through the detector unit through duct.

In order to prevent the said condensate water from being formed, it is already a common practice to blow low pressure air into the tubular narrow space between the cigarette rod surface and the inner wall of the said detector unit through duct.

Besides the mentioned inconvenience deriving from the formation of condensate water, another drawback is originated by the fact that cigarette rod lengths might stop in the through duct ofthe detec tor unit for example owing to any incorrect manual insertion of the cigarette rod into the detector unit, or owing to any accidental stopping ofthe cigarette making machine to which the said detector unit is applied.

The present invention aims to obviate the above s mentioned drawbacks, and for this purpose it prop ;oses to associate with the continuous blowing of low pressure air into the detector unit through duct, also an occasional blowing of air at a higher pressure, sufficient for producing a temporary air jet which is adapted for ejecting from the said through duct any cigarette rod lengths which stopped thereinto, owing to any irregular operation, or to any discon tinuous running of the cigarette-making machine.

According to the invention, a high pressure air duct supplied from a source of air at a definitely higher pressure, is connected to the low pressure air feeding line leading to a nozzle located at the inlet of the detector unit through duct, for blowing air into said duct. In the said high pressure air duct there is arranged a controllable intercepting device, such as a manually or electrically operated valve, which upon control opens for a limited time the way to the nozzle for a temporary airflow, strong enough for expelling from the through duct of the detector unit any cigarette rod lengths which remained stationary in said duct.

The characteristic features of the invention, and the advantages arising therefrom will appear evident from the following detailed description of same, made with reference to the accompanying drawing, schematically showing a detector unit for sensing the weight per unit length, or specific weight, of the tobacco filler of a cigarette rod, and which is equipped with a compressed air, intermittently operated, ejector device according to the invention.

Referring to the drawing, reference numeral 1 designates a detector unit for continuously sensing the weight per unit length, or specific weight, of the tobacco filler of a cigarette rod B during the guided, axial forward movement of this rod B from the drier that dries the glued portion of its tubular paper wrapper, to the cutter th at cuts the rod into cigarette lengths.

In the detector unit 1 the cigarette rod B is caused to travel, with a certain clearance, through the through duct 2 in which the specific weight of its tobacco filler is sensed. At the inlet of duct 2 (relatively to the cigarette rod B advancing direction) an annular nozzle 3 for blowing air into duct 2 is mounted into axial alignment therewith, and low pressure air is supplied from a source (not shown) through the feed line 4,5 andthe delivery conduit 6.

By blowing low pressure air into the detector unit through duct 2, the annular nozzle 3 promotes the forming of a stream through the annulargap between the inner wall of duct 2 and the surface of the cigarette rod B which is travelling through duct 2.

This air stream not only cools the cigarette rod B and prevents any condensate from being formed on the inner wall of said duct 2, but also forms a fluid layer that considerably reduces the sliding friction of the cigarette rod B on the said inner wall of duct 2.

According to the present invention, the same annular nozzle 3 is used, when needed, as a pneumatic ejector for expelling from the through duct 2 in which the specific weight of the tobacco filler is sensed, and from the adjoined outled duct 7 which guides the cigarette rod B to the cutter, any cigarette rod lengths which might have stopped thereinto, owing to any incorrect insertion of rod B into the detector unit, orto any accidental stopping ofthe cigarette-making machine.

In order to use, according to the invention, the said nozzle 3 as a pneumatic ejector, a duct8 is provided, which is connected by one end to duct 5 of the feed line4 (which supplies low pressure cooling airto nozzle 3) and by the other end to duct 9 delivering air at a pressure much higher than the air flowing through the feed line 4, 5, and typically at a pressure in the order of about 2 or 3 Kgs./sq.cm.

Between duct 9 and duct 8 a control means is fitted for intercepting the flow of the high pressure air. In the drawing, this control means is shown in form of a cock 10, provided with a manually operated lever 11.

Thus, whenever cock 10 is manually opened for a limited time, the pneumatic nozzle 3 causes a strong air jet to penetrate into duct 2 so as to expel therefrom and from adjoining duct 7 any cigarette lengths having remained stationary thereinto, owing to any incorrect insertion of a cigarette rod B into the detector unit, or to any accidental stopping of the cigarette making machine.

The present invention provides also for an automatic operation of the ejector nozzle 3. In this case, instead of a cock, the controllable intercepting means 10 consists of an electrically operated valve.

The automation ofthe ejector nozzle 3 is required when the cigarette-making machine is equipped with devices forthe automatic breaking of the cigarette rod at any stopping of the cigarette-making machine, and for the automatic insertion of the cigarette rod into the detector unit, as the said machine is started.

Claims

1. A pneumatic ejector device for expelling cigarette rod lengths from the through duct of the detector unit in which the weight per unit length of the cigarette rod tobacco filler is sensed, the said detector unit being operatively fitted in the path of a cigarette rod from the drier that dries the glued portion of its tubular paper wrapper, to the cutterthat cuts the cigarette rod into cigarette lengths, the said ejector device being characterized by the fact that it comprises an annular pneumatic ejector nozzle located at the inlet of the through duct of the detector unit, relatively to the direction ofthe cigarette rod movementtherethrough, the said nozzle being fed from an airfeeding line, which is adapted for being temporarily connected, through a controllable intercepting means, with a source of air at a relatively high pressure, whereby an air jet is blown from the nozzle, strong enough for expelling from the said through duct of the detector unit and from the adjoining outlet duct, any cigarette rod lengths which remained stationary therein, owing to any incorrect manual insertion of a cigarette rod into the detector unit, orto any breaking ofthe cigarette rod, due to any accidental stopping of the cigarettemaking machine.

2. The pneumatic ejector device according to Claim 1, characterized by the fact that the said air feeding line to the ejector nozzle conveys also an airflow from a low pressure air source into the through duct of the detector unit, so that during the normal operation of the cigarette-making machine, low pressure air is blown continuously thereinto, in order to prevent any condensate from being formed on the inner wall of said through duct, and to maintain between the cigarette rod surface and the inner wall ofthe through duct of the detector unit an air layer which facilitates the travelling of the cigarette rod through the said duct.

3. The ejector device according to the preceding Claims, characterized by the fact that the said source of air at a relatively high pressure, supplies air at a pressure in the order of about 2 or 3 Kgs./sq.cm.

4. The ejector device according to the preceding Claims, characterized by the fact that the said controllable intercepting means is a manually operatable valve.

5. The ejector device according to Claims 1 ta;3, characterized by the fact that the said controllable intercepting means comprises an electrically operated valve.

6. A pneumatic nozzle ejector device for expelling cigarette rod lengths from the detector units for sensing the weight per unit length of cigarette rods, the whole or in part substantially as shown and as described.