US2140720A - Apparatus for severing an axially moving rod into lengths - Google Patents

Description

Dec. 20, 1938. FER A W 2,140,720

APPARATUS FOR SEVERING AN AXIALLY MOVING ROD INTO LENGTHS Filed Nov. 27, 1936 Patented Dec. 20, 1938 UNITED STATES PATENT OFFIQE APPARATUS FOR SEVERING AN AXIALLY' MOVING ROD INTO LENGTHS London, England Application November 27, 1936, Serial No. 113,053

In Great Britain December 17, 1935 13 Claims.

This invention is for improvements in or relating to apparatus for severing an axially moving rod into lengths.

The invention is primarily intended for use with cigarette making machines of the continuous rod type, in which case the severing device may comprise a rotatable circular disc knife or a sickle shaped knife, but it may also be applied to other purposes by substituting an abrasive cutter (e. g., a wheel) or other cutter for the knife which is used when cutt'mg a cigarette rod. For convenience the term knife will be used throughout for all types of cutter.

In order to eifect satisfactory severing or cutting of a moving rod, it is necessary that the knife shall have two movements, or the equivalent thereof, namely, translation of the knife parallel to its own plane in the direction in and at substantially the same speed at which the rod is I moving, and an edgewise movement of the knife towards the rod in order to effect the cutting, and where a rotatable knife is used the third movement, namely, rotation ofthe knife disc.

The present invention provides improved means for giving the knife the necessary movements whereby the knife passes through an orbit which is preferably of circular or elliptical shape. The shape of the orbit is determined by the amplitude and relative velocity of the two first said movements which may be combined in a single rotary movement where a circular orbit is desired.

According to one form of the present invention there is provided a cutting mechanism comprising in combination a support, a member anchored thereto by universal joint (e. g. a Hookes joint), a knife carrier pivoted to said member to swing in one plane only relatively to said member, means to impart to the member an orbital movement in such manner that a line joining the centre of the universal joint and the-axis of the carrier pivot sweeps out a conical surface, whilst the axis of the carrier pivot is maintained 45 parallel to its initial position, a knife on the knife carrier and means to maintain the carrier or the carrier and the knife at all times parallel to a given plane (e. g. a plane normal to a continuously moving rod which is to be severed).

The means for maintaining the knife parallel may comprise a second member mounted to have the same movement as the first said member and connected to the knife carrier by a pivot which is parallel to the first said carrier pivot in such manner'that the centres of the universal joint and axes of the pivots are at the corners of a parallelogram.

The distance between the knife and centre of the universal joint is different from the distance between the pivot and the universal joint on the 5 member or members whereby the knife is movable through an orbit of elliptical shape.

Further; according to the present invention, there'is provided a cutting mechanism comprising a knife mounted on a carrier, a pivoted mem- 10 ber mounted to sweep out a conical surface of revolution, and connected to the knife carrier, whereby the knife is caused to traverse an orbit, and means for maintaining the knife in parallel planes at all times (e. g. normal to the axis of 5 the moving rod during the movement of the knife through the orbit). The member may be arranged as a lever of the first order in which case it generates two conical surfaces of revolution.

Again, according to the present invention there is provided a cutting mechanism comprising a knife mounted on a carrier connected by pivoted links to a member, said knife being disposed at a distance from the member diiferent from that of the line joining the carrier pivots, the carrier, links and member together forming a parallelogram, said member in turn being pivotally mounted for oscillation about an axis at right angles to the link pivots, a lever pivoted to said member at a point on its axis and operatively 30 connected to the parallel links and driven through a circular path at one end whereby a conical movement is imparted to the lever and the knife is moved through an orbit of elliptical shape.

In all cases means may be provided for rotating the knife on its axis when required.

The invention will be described by way of example with reference to the accompanying drawing in which Figure l is a side elevation partly in section of cutting mechanism for cutting a continuous cigarette rod.

Figure 2 is a plan of a part of Figure 1.

Like references refer to like parts throughout the specification and drawing.

With reference to the drawing, a circular knife 5 is mounted on a spindle 5 carried in bearings l which are attached to bracket 8. The bracket 8 is secured by bolts 30 to a carrier 3| which is adapted to form one link of a paral el link mechanism. The bearings I, bracket 8 and carrier 3| combined will be referred to hereinafter as the knife carrier. v

The carrier 3| is pivoted at 9 and It] to two parallel links H and I2 which are themselves pivoted at I3 and I4 respectively to a support shown as a shaft I5 so that the four pieces together form a jointed parallelogram. The shaft I5 to which the parallel links II and I2 are pivoted is rotatable in bearings Iii formed in a bracket I? attached to the bed of the cigarette machine. The axes of the pivots I3 and I4 of the links II and I2 to the shaft intersect the axis of the latter thus forming two Hookes joints or universal joints, and the parts are so disposed that the axis of the shaft I lies parallel to the direction of movement of the cigarette rod and the axis of the circular knife 5 is also parallel to the cigarette rod. It will be seen from Figure 2 that the distance between the axis of rotation of the knife 5 and the centres I3 and I4 of the universal joints is greater than the distance from the centres of the joints I3 and I4 to the pivots 9 and ID of the links I I and I2 to the knife carrier. 7

The cigarette rod is passed through a ledger tube 35 which moves with the cigarette rod during the cutting operation, in the usual manner.

The link I2 has an extension I8 beyond the pivot I4 which attaches it to the shaft 1, and this extension is coupled to a crank disc IS in such a manner that when the disc is rotated the extension I8 of the link I2 sweeps out a conical surface, the centre point of the pivot I4 being the apex of the cone. The link I2 thus forms a lever of the first order.

The crank disc I9 is mounted on a shaft 20, and the end of the extension I8 fits in a ball race 2| fixed on the crank disc I9.

It will be seen that that part of the link I2 which is disposed between the pivots I0 and I4 also sweeps out a cone.

The shaft 29 is rotated by gearing 33 and 34 driven from the main drive of the cigarette making machine.

When the apparatus is working the throw of the knife 5 in a plane at right angles to the axis of the shaft I5 is greater'than the throw in the direction of the shaft. In cigarette machines as usually constructed the cigarette rod is horizontal, and as previously stated, the shaft I5 is supported parallel to the cigarette'rod. Consequently, the orbit of the knife 5 is an ellipse with the major axis substantially vertical and the proportion of the major axis to the minor axis may be increased or decreased by decreasing or increasing respectively the length of the link I2 relatively to the distance of the knife 5 from the axis of the shaft I5.

The mechanism thus gives a translation of the knife parallel to itself and by suitably proportioning the parts the knife may be arranged to travel at the desired speed during the cutting operation, and as it is desirable that the cutting should be effected in the shortest possible time, the ellipse referred to is made relatively flat and the cutting operation takes place while the knife is passing through one of the extremities of the ellipse of smallest curvature, i. e., a portion of the curve near to a focus.

The edgewise movement of the knife 5 is naturally obtained owing to the fact that as the knife sweeps through its elliptical orbit, the bottom edge of the knife dips towards and through the cigarette rod.

The mechanism for rotating the knife 5 on its spindle 6 may be of any desired kind, but a simple and convenient device consists in mounting a grooved pulley' 22 on the end of the knife spindle 6 Opposite to that at which the knife 5 is located and driving this pulley by a belt 23 running around a pulley 24 mounted at some suitable part of the machine.

As the belt 23 will be fairly long in comparison with the pulley diameters, an ordinary leather belt will be suitable as the distance between the centres of the pulleys does not change appreciably, but if desired, an elastic belt may be used.

It is frequently necessary when operating a cigarette machine to change the length of the knife throw in order to produce cigarettes of a different length, and in the present case this is accomplished by altering the radius of the base of the cone swept out by the end of the lever which is connected to the crank disc.

A convenient way of effecting this is to make the face of the crankdisc I9 of concave spherical shape as shown in Figure 1 with a groove 25 across the concave face passing through the centre thereof. The ball race 2| is mounted in a block 26 slidable in the groove 25 and by this means the end of the lever may be moved to any desired point along this groove to alter the crank radius and fixed in the desired position. The block is secured in position after adjustment by bolts 21 and 28.

It will be appreciated that any suitable means may be provided to sharpen the knife, such means being well known in the art.

As will be seen from Figure 1, the bottom of the bracket 8 is provided with serrations 32 which co-operate with similar serrations formed on the carrier 3|. The purpose of this arrangement is to permit the knife 5 to be adjusted to compensate for wear, for example, wear due to the grind ing of the knife.

Where a sickle shaped knife (i. e. an eccentric edged knife) is used it may be mounted on a disc for rotation, in which case the mechanism will be similar to that already described, but in certain cases rotation may be dispensed with providing that the angle of the sickle is steep enough for the knife to make a satisfactory cut by a shearing action.

What I claim as my invention and desire to secure by Letters Patent is:

1. A cutting mechanism comprising in combination a support, a member anchored thereto by a universal joint,'a knife carrier pivoted to said member to swing in one plane only relatively to said member, means to impart to the member an orbital movement in such manner that a line joining the centre of the universal joint and the axis of the carrierpivot sweeps out a conical surface, a knife on the knife carrier and means to maintain the knife at all times parallel to a given plane.

2. A cutting mechanism comprising a knife mounted on a-carrier, a pivoted member mounted to sweep out a conical surface of revolution, and connected to the knife carrier, whereby the knife is caused to traverse an orbit, and means for maintaining the knife in parallel planes at all times.

3. A cutting mechanism comprising. a carrier, a knife mounted on the carrier, a support, links connecting the carrier with the support, carrier pivots connecting the links with the carrier, link pivots connecting the links with the support, said knife being disposed at a distance from the support different from that of the line joining the carrier pivots, the carrier, links and support together forming a parallelogram, said support in turn being journalled for oscillation about an axis at right angles to the axes of said link pivots,

and a lever pivoted to said support, the pivotal axis of the lever intersecting the axis of the support, said lever being operatively connected to the parallel links and its extremity driven through a circular path whereby a conical movement is imparted to the lever and the knife is moved 7 through an orbit of elliptical shape.

4. A cutting mechanism for severing a continuously moving rod comprising in combination a support, a member anchored thereto by a univ-ersal joint, a knife carrier pivoted to said member to swing in one plane only relatively to said member, means to impart to the member an orbital movement in such manner that a line joining the centre of the universal joint and the axis of the carrier pivot sweeps out a conical surface, a knife on the carrier, and means to maintain the knife at all times parallel to a plane normal to the continuously moving rod.

5. A cutting mechanism for severing a continuously moving rod comprising a knife mounted on a carrier, a pivoted member mounted to sweep out a conical surface of revolution and connected to the knife carrier, whereby the knife is caused to traverse an orbit, and means for maintaining the knife at all times in parallel planes which planes are normal to the axis of the moving rod during the movement of the knife through the orbit.

6. A cutting mechanism comprising in combination a support, a lever of the first order anchored to the support by a universal joint, a knife carrier pivoted to said lever to swing in one plane only-relatively to the lever, means to impart to the lever an orbital movement in such manner that a line joining the centre of the universal joint and the axis of the carrier pivot and extended beyond the centre of the universal joint sweeps out two conical surfaces of revolution, the apexes of the conical surfaces of revolution being coincident with the centre of the universal joint, a knife on the knife carrier, and means to maintain the knife at all times parallel to a given plane.

'7. A cutting mechanism comprising a knife mounted on a carrier, a pivoted lever of the first order connected to the knife carrier and mounted to sweep out two conical surfaces of revolution, the apexes of the conical surfaces of revolution being coincident with the centre of the pivot of said lever, whereby the knife is caused to traverse an orbit, and means for maintaining the knife in parallel planes at all times.

8. A cutting mechanism comprising in combination a support, a member anchored thereto by a universal joint, a knife carrier pivoted to said member to swing in one plane only relatively to said member, means to impart to the member an orbital movement in such manner that a line joining the centre of the universal joint and the axis of the carrier pivot sweeps out a conical surface, a knife on the knife carrier, and a second member mounted to have the same movement as the first said member and connected to the knife carrier by a pivot which is parallel to the first said carrier pivot in such manner that the centres of the universal joint and the axes of the pivots are at the corners of a parallelogram, whereby the knife is at all times maintained parallel to a given plane.

9. A cutting mechanism comprising in combination a support, a member anchored thereto by a universal joint, a knife carrier pivoted to said member to swing in one plane only relatively to said member, means to impart to the member an orbital movement in such manner that a line joining the centre of the universal joint and the axis of the carrier pivot sweeps out a conical surface, a knife on the knife carrier, and means to maintain the knife at all times parallel to a given plane, the distance between the knife and the centre of the universal joint being different from the distance between the pivot and the universal joint on the member, whereby the knife is movable throughout an orbit of elliptical shape.

10. A cutting mechanism comprising a circular knife journaled for rotation on a carrier, mechanism to rotate said knife about its axis, a pivoted member mounted to sweep out a conical surface of revolution and connected to the knife carrier, whereby the knife is caused to traverse an orbit, and means for maintaining the knife in parallel planes at all times.

11. A cutting mechanism comprising a knife journalled for rotation on a carrier, mechanism to rotate the knife about its axis, pivotal links connecting said carrier to a support, said knife being disposed at a distance from the support different from that of the line joining the carrier pivots, the carrier, links and support together forming a parallelogram, said support in turn being journalled for oscillation about an axis at right angles to the link pivots, and a lever pivoted to said support, the pivotal axis of the lever intersecting the axis of the support, said lever being operatively connected to the parallel links and its extremity driven through a circular path, whereby a conical movement is imparted to the lever and the knife is moved through an orbit of elliptical shape.

12. A cutting mechanism comprising in combination a support, a member anchored thereto by a universal joint, a knife carrier pivoted to said member to swing in one plane only relatively to said member, means to impart to the member an orbital movement in such manner that a line joining the centre of the universal joint and the axis of the carrier pivot sweeps out a conical surface, a knife on the knife carrier, means to maintain the knife at all times parallel to a given plane, and means to move said knife relatively to the carrier to adjust the knife to compensate the knife for wear.

13. A cutting mechanism comprising a knife mounted on a carrier, a pivoted member mounted to sweep out a conical surface of revolution and connected to the knife carrier, whereby the knife is caused to traverse an orbit, means for maintaining the knife in parallel planes at all times, and means to move the knife relatively to the carrier to adjust the knife to compensate the knife for wear.

FELIX FREDERIC RUAU.

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