GB2056936A - Presser chain for conveying tobacco to a cutting drum of a tobacco cutter - Google Patents

Abstract

A presser chain for conveying tobacco to a cutting drum of a tobacco cutter comprises plate-shaped chain links 23 interconnected by pivot pins 34 inserted in bearing formations of the chain links. The bearing formations 28 are provided with radial openings which are narrower than the diameter of the pivot pins. The pivot pins are securely connected to members of the chain links and are provided with a flat which extends substantially parallel to the conveyance surface. The chain links 23 are preferably arranged offset relatively to each other transversely to the conveying direction. <IMAGE>

Description

SPECIFICATION Presser chain for conveying tobacco to a cutting drum of a tobacco cutter Presser chain for conveying tobacco to a cutting drum of a tobacco cutter.

The invention relates to a presser chain for conveying tobacco to a cutting drum of a tobacco cutter, comprising plate-shaped chain links which are connected together in a hinge-like manner by means of pivot pins inserted in bearing eyes of the chain links.

It is known that the tobacco leaves are conveyed to a cutting drum for tobacco cutters on endless conveyors in the form of two converging presser chains which compress the tobacco to a cake and form the counter supports for the pressure of the cutter blades. These presser chains consist of adjacently disposed chain links which are arranged transverse to the conveyance direction and which are in the form of plate-shaped profiled members which interengage in the manner of a hinge and which are mostly drawn from corrosion-resistant metal.

In this case a presser chain may be assembled in a known manner (US-PS 3 202 266) from one kind of several kinds (upper and lower members) of chain links which on the one hand are provided with a bearing bush and on the other hand with a bearing rod which must be pushed together or drawn apart from the side over their entire length during assem bland dismantling, respectively, of the presser chain.

Another known presser chain (US-PS 3 245 517) consists of chain links which comprise bearing eyes into which pivot pins are laterally inserted, or withdrawn therefrom, during assembly and dismantling, respectively, of the chain.

In the operation of such presser chains it has not been possible in spite of numerous measures to prevent soiling of the chain links and in particular of their joints or hinge connections, respectively, by leaf portions and adhering or water soluble component parts of the tobacco leaves entering into the gap between the chain links. This problem occurs already with un-sauced tobacco leaves to be cut, but to a considerably higher degree with sauced tobacco leaves.The penetration of such sticky component parts into the gap between the chain links causes the operational characteristics of the presser chains consisting of such chain links to deteriorate very quickly, in that tobacco crusts are formed which produce friction resistances in particular at the joint locations; such friction resistances render difficult to a considerable extent the mobility of the presser chain and its dismantling.

The invention is based on the object to construct the presser chain, or its connecting links, respectively, in such a manner that its dismantling is facilitated and thereby the period of time required for its cleaning is shortened considerably.

Beyond this, it is endeavoured to reduce the soiling right from the start and thereby to increase the running time of the chain between two cleaning intervals.

This problem is solved according to the invention in that the bearing eyes are provided with radial openings which are narrower than the diameter of the pivot pins and that the pivot pins are securely connected to members of the chain links and are provided with a radial flat which extends substantially parallel to the conveyance surface.

With this construction of the presser chain and of its connecting links it is now possible during assembly to insert the pivot pins into the bearing eyes substantially perpendicularly to the conveyance surface of the chain links and to lock them radially and axially by rotation ofthe chain links which are securely connected to the pivot pins, into the plane of the conveyance surface, orto proceed in the reverse sequence during dismantling, i.e. to rotate individual chain links and pivot pins relatively to each other through approximately 90 and thereafter to remove the pivot pins radially from the bearing eyes.

According to a preferred embodiment the openings are provided on the side remote from the conveyance surface of the chain links.

In this embodiment the openings of the bearing eyes which face away downwardly from the conveyance surface are additionally better protected against soiling. Moreover the presser chain is open downwardly at the abutment locations of two chain links, so that contaminations can drop through downwardly and may be scraped off.

For the purpose of uniform distribution of the shear forces over the length of a pivot pin the presser chain consists advantageously of chain links which are divided several times along its width and which are arranged offset relatively to each other transverse to the conveyance direction.

According to an advantageous embodiment, locking between pivot pins and chain links is obtained by the fact that the pivot pins are provided at their outer ends with chain links which comprise recesses and which interengage with corresponding chain links of adjacent pivot pins.

One constructional example ofthe invention is illustrated in the drawing and is described below in detail. There are shown in: Fig. 1 a diagrammatically illustrated tobacco cutter in longitudinal section, Fig. 2 a portion of the presser chain according to the invention, in a view from above, Fig. 3 a section through the presser chain in the region of a driving toothed crown, on the line Ill-Ill according to Fig. 2, Fig. 4 a chain link in perspective illustration, and Fig. 5 a portion of a pivot pin with a member of a chain link fixed to its end.

Fig. 1 illustrates a commercial tobacco cutter of the type KT of Hauni-Werke, Hamburg-Bergedorf; the construction and manner of working thereof will be briefly explained below.

For the purpose of conveying, cake forming and pressing the leaf material 1 which is supplied by a storage source is fed in a duct 2 by a rake 3 rhythmically in a steady procession to a pressing device 7 which consists of two presser chains 4,6. The presser chains which converge towards each other in the conveyance direction (arrow) and which are drivable by a drive 8 engage the leaf material 1 and convey it to a mouthpiece 13 which consists of an upper member 11 and a lower member 12, while pressing and condensing itto a cake 9. A pressure generator 14 acts upon the presser chain 4. The lower member 12 forms the counter-cutterforthe cutters 16 in a cutting drum 18which is rotatable bya drive 17, so that during rotation the cutters 16 cut narrow strips of tobacco filaments 19 off the tobacco cake 9.The tobacco filaments 19 are subsequently conveyed away.

A grinding disc 21 which is dressed by a diamond 22 servesforgrinding the cutters 16.

Fig. 2 illustrates one of the presser chains with further details, the oppositely disposed second presser chain 6 being of identical construction. The presser chain 4 consists of individual chain links 23 one of which is illustrated in perspective representation in Fig. 4. In the present constructional example four adjacently disposed rows of chain links 23 are provided; it is obvious that even further rows of chain links 23 may be added thereto, if required.

The individual chain links 23 are arranged offset relatively to each other transversely to the conveyance direction (arrow). This is rendered even more clearly once more in a section through the presser chain according to Fig. 3, according to which always in the centre of the chain links 4 illustrated in full lines, of the front row, two chain links illustrated by broken lines, of the back row contact each other by their outer surfaces 26 at their front ends, and vice versa. Each chain link 23 is provided with flat grooves 27 for gripping the leaf material. Moreover, at both ends the chain links 23 are provided with bearing eyes 28; the outer surfaces 26 at the end faces extend concentric thereto, and at the underside of the chain link 23 which is remote from the conveyance surface 29, the bearing eyes 28 comprise an opening 31 the walls of which diverge outwardly.

The openings 31 serve for the engagement of teeth 32 of a driving toothed crown 33 and for the insertion of pivot pins 34 which connect the chain links 23 one to the other in the manner of a hinge. The position and magnitude of the openings 31 is so selected that always either a broad centre ledge 36 or two outer ledges 37 limited by the outer surfaces 26 of the chain link 23 engage accurately into the grooves 38 between two teeth 32 of the driving toothed crown 33.

The openings 31 of the bearing eyes 28 are smaller at their narrowest location than the diameter of the pivot pins 34. The pivot pins 34 are provided with a radial flat 39 which in the assembly state in the conveyance direction 24 extends approximately parallel to the conveyance surface 29 of the chain links 23.

During the assembly, or the dismantling, respectively, of the presser chain 4 the pivot pins 34, or the chain links 23, respectively, are rotated through approximately 90 relatively to adjacent chain links, so that the pivot pins 34 with their flat 39 can pass through the narrowest location of the openings 31 of the bearing eyes 28, so that the chain links 23 can be easily connected one to the other, or separated from each other, respectively.

At their outer ends (Fig. 5 shows only one end of a partly illustrated pivot pin) the pivot pins 34 accord ing to Figs. 2 and 5 comprise chain links 41 which are securely connected to the pivot pins 34 and which are provided with alternately oppositely disposed recesses 42 which give them an approximately Z-shaped appearance. The recesses are engaged by the correspondingly constructed neighbouring chain links 41 of an adjacent pivot pin 34. In their state in which they are swung into the plane of the con veyance surface, of these chain links 41, they thus lock in an axial direction the rows arranged on the pivot pins 34, of the chain links 23 enclosed by them.

In this assembly state the individual chain links 23 are also radially secured on the pivot pins 34, since the pivot pins 34 cannot pass any more by their largest diameter through the narrowest location of the openings 31 of the bearing eyes 28.

Claims (5)

1. A presser chain for conveying tobacco to a cutting drum of a tobacco cutter, comprising plateshaped chain links interconnected by pivot pins inserted in bearing formations ofthe chain links, said bearing formations being provided with radial openings which are narrowerthan the diameter of the pivot pins, and said pivot pins being securely connected to members of the chain links and each being provided with a flat which extends substantially parallel to the conveyance surface.

2. Presser chain according to claim 1, wherein the openings are provided on the side remote from the conveyance surface of the chain links.

3. Presser chain according to claim 1 or 2, wherein the presser chain consists of chain links which are divided several times along their width and which are arranged offset one to the other transverse to the conveyance direction.

4. Presser chain according to any one of claims 1 to 3, wherein the pivot pins are provided at their outer end with chain links which have recesses and which interengage with corresponding chain links of adjacent pivot pins.

5. A presser chain for conveying tobacco to a cutting drum of a tobacco cutter, substantially as herein described with reference to and as illustrated in the accompanying drawings.