US 3377896 A
Description (OCR text may contain errors)
April 16, 1968 H. DE CORTA DEVICE FOR TRIMMING THE EDGE OF METAL STRIP Filed April 5, 1966 5 Sheets-Sheet 1 .ZIIr
HUBERT dc. CORTA 'TRNEYS April 16, 1968 H. DE CORTA 3,377,396
DEVICE FOR TRIMMING THE EDGE OF METAL STRIP Filed April 5, 1966 3 Sheets-Sheet 2 \NVEN QRI H U BERT Ac CORTA AT QRNEIS April 16, 1968 H. DE CORTA 3,377,395
DEVICE FOR TRIMMING THE EDGE OF METAL STRIP 5 Sheets-Sheet 5 Filed April 5, 1966 m m N \NYENTOR HUBERT A: CORTA RNEYS ATT United States Patent 14 Claims. (Cl. 83-3) This invention relates to improvements in a device for trimming the edges of metal strip as this moves continuously past the device. It is of particular, but not exclusive, application where continuous runs of welded tube are to be produced from slrip metal unwound from a coil.
As is well known, strip metal is subject to faults of three particular kinds: (a) is edges are irregular in shape and structure; (b) its longitudinal centre line is not straight, but wavy; and, finally (c) its wid.h is not constant.
In order to render the strip more suitable for subsequent use (in making welded tubing, for example), it is desirable to trim the edges of the strip, that is to say to do away with edge irregularities and also, in some cases, to make the width of the strip the same throughout. For this, one could use a planing machine, which cuts the moving strip. However, as the strip is not straight lengthwise, but often presents itself like a curved sword blade,
the plane fails to bite'at some points along the edge, of
the strip while biting too deeply at others. This fault is still more serious when the strip is covered with scale, because, after every break in the shaving, the plane must first cut through the scale, which, owing to its abrasive nature, causes rapid wear on the tool.
It is an object of the present invention to provide an improved device for trimming at least one edge of a continuously advancing metal strip which device shall not be subject to the disadvantages referred to, at least to the same extent as hitherto.
For this purpose, the device here proposed, which enables at least one edge of a continuously advancing strip to be trimmed, comprises a plate member mounted so as to swing about a vertical pivot and bearing two fixed rollers at the side lying towards the edge of the strip to be trimmed. Between these rollers, a trimming or cutting tool is fitted. The plate member also carries at least one roller which is resiliently displaceable to push against the opposite edge of the metal strip, so as to ensure that the edge on which the tool does its work bears at all times against the fixed rollers.
This device makes it possible to trim the metal strip, that is to say to eliminate irregularities from one of its edges, notwithstanding the winding nature of its longitudinal centre line. The shaving produced is continuous. With scaly strip, this is of particular advantage, as the tool need not cut repeatedly through the scale.
For trimming the other or opposite edge of the strip, use may be made of a second such device, in which the positions of the fixed rollers and tool on the one hand and the moving roller or rollers on the other are reversed in relation to the longitudinal centre line of the metal strip.
It is also possible, in another embodiment of the invention, to combine two such devices into one, producing a piece of equipment with which both edges of the strip can be trimmed at once for the removal of irregularities. To do this, all that is required is to provide a second plate member capable of motion in relation to the first, the first one carrying two fixed rollers with a tool between them, while the second one, which likewise carries two fixed rollers with a tool between them, is acted on by spring means or the like tending to urge the two sets of rollers towards each other.
In one preferred form of equipment embodying the invention principle, the cutting tool used for trimming the edges of the strip is of a circular shape generated by the revolution of a conventional cutter profile, which, in the cutting position, has its clearance angle and angle of presentation positive and within the axis and which has its axis of rotation offset from the plane of the strip, so that the tool is rotated by the movement of the strip itself, thereby enabling the use of a driving motor to be dispensed with in most cases. One advantage of a circular cutter of this kind is that it has a far longer life than that of a conventional fixed cutter. This results in a considerable reduction in the number of production hold-ups caused by tool replacements. Moreover, when the axis of rotation of the tool lies above the plane of motion of the metal strip, the continuous shaving is automatically discharged downwards. Another advantage of this arrangement is that the zone of contact between the strip and the rotating tool, which zone lies below the axis of rotation of the tool, itself inclined in relation to the direction of advance of the metal strip, gives rise to the formation of a chamfer. This chamfer is of special advantage where the strip is used for the production of welded tubes, since it is directed the right way for the subsequent longitudinal welding of the two edges after these have been brought together. The angle of this charnfer can be regulated either by varying the distance between the axis of rotation of the cutter and the plane of the strip or by slightly inclining the axis of rotation of the cutter to the plane of motion of the strip. Finally, the cooling of such a circular tool is very easy, as experience has shown that a simple jet of water or other cooling liquid suffices for the purpose.
In addition to doing away with irregularities in the edges, it may also be desirable to bring the strip to a constant width throughout. The invention also includes an apparatus with which this second operation can be carried out in conjunction with the device or devices used for trimming the edges.
In one form of such an apparatus, the edge-trimming devices are followed by a device comprising an additional plate member capable of swinging about a pivot and bearing at least two fixed rollers and two moving rollers pushed towards the fixed rollers by spring action or the like, a fixed tool being mounted on the plate between the moving rollers. The tool acting on one edge of the metal strip is thus stationary in relation to the rollers against which the other edge of the strip bears. This device may be followed by one or more similar devices, according to the width equalization desired.
In another form of such an apparatus, one device for trimming one of the edges of a metal strip is combined in one and the same machine with a device for reducing the strip to the same width throughout, both operations being carried out at once. For this purpose, all that is necessary is to add to the device (consisting of a cutting tool mounted between first and second rollers carried on a movable plate, with two dis-placeable rollers pressed by springs or the like towards the first and second rollers) a further cutting tool carried by the plate between the two displaceable rollers. While the first tool serves to trim one of the edges, the other or further tool is used for reducing the strip to the same width throughout.
Again, should it be desired to achieve this regularity of width by removing equal shavings simultaneously from both edges of the strip, this can be done with a further variant of the device according to the invention.
In this variant, the plate member which is displaceable about a pivotal axis carries two cutting tools in fixed positions, each fitted between a trailing roller and a displaceable leading roller, the two leading rollers, which are intended to guide the strip by its edges, being mounted on a sysetm whereby the longitudinal centre line of the strip is maintained substantially equidistant from the two tools.
In one form of this variant, in order to maintain the longtiudinal centre line of the strip equidistant from the two tools, the displaceable rollers are mounted on articulated levers provided with toothed sectors in mesh with each other, elastic components being used to press these moving rollers towards each other.
Some embodiments of the invention will now be described by way of example, reference being made to the accompanying drawings, in which:
FIGURE 1 is a plan of one form of device for trimming one of the edges of a metal strip in accordance with the invention;
FIGURE 2 is a cross-section taken on the line 11-11 of FIGURE 1;
FIGURE 3 is a diagrammatic plan of one form of apparatus with which a metal strip can have each edge trimmed in turn and its width made the same throughout;
FIGURE 4 shows in diagram form a combination device for trimming both edges of a strip simultaneously;
FIGURE 5 shows in diagram form a variant of the invention in which one edge of a strip is trimmed at the same time as the strip is being brought to a uniform width throughout; and
FIGURE 6 shows in diagram form another variant, with which substantially equal shavings can be removed from both edges.
The device shown in plan in FIGURE 1 enables one edge of a continuously advanced metal strip F to be trimmed, in order to do away with irregularities in that edge. It comprises a plate 1, which takes the form of a frame containing a substantially rectangular central slot or aperture 2. The two sides of frame 1 run parallel to the diretcion of advance of the metal strip and each carries a system of rollers, one to bear against the edge that is to be trimmed and the other to bear against the opposite edge. p The first system includes a leading roller 3, which is stationary in relation to the plate but can have its position varied in relation to the plate. For this purpose, a spindle 4 of this roller 3 is carried by a small plate mounted (dovetail-fashion, for example) in a slide 5 so that it can slide in relation to a stationary block 6, fixed to plate 1. Means are provided, numbered generally 5', for locking the rollers spindle 4 in the desired position.
Rearwardly of the roller 3, in the direction of advance of the strip, but in the immediate vicinity of this roller, a trimming cutter 7 is locked in position. In the form illustrated, which is to be preferred, this cutting tool is a circular cutter conceived as generated by the revolution of a conventional cutting tool, that is to say that any radial section of tool 7 is identical to the longitudinal section of a conventional cutter, with the same cutting and clearance angles etc. The tool 7 is carried on a spindle 8 which rotates in a block 9, the position of which in relation to plate 7 can be varied by any accepted method whereby, in particular, the inclination and position of the tool 7 can be varied in relation to a tangent from the roller 3 parallel to the direction of advance of strip F. Forexample, the angular position of tool-holder block 9 can be fixed with the aid of bolts 10 screwed into a plate 11 with shims of variable thickness in between. The plate 11 is mounted (dovetail-fashion, for instance) in a slide 13, in which it is locked by some accepted means, numbered generally 14. In addition, the tool spindle 8 lies outside and preferably above the plane containing the longitudinal centre line of the metal strip F. The spindle 8 may be horizontal or it may be slightly inclined in relation to the plane of motion of the strip, so as to regulate the angle of chamfer. The distance between the spindle 3 and the plane of the strip, measured perpendicularly from the edge to be cut, is so pre-determined that the translational movement of the strip causes the tool 7 to rotate while imposing the minimum stress on the bearings of the spindle 8.
To complete the guidance of the strip, it is desirable, as indicated in thedrawing, to provide a second roller, 15, identical to the first, that is to say, stationary in relation to plate 1 but adjustable as to its position, this second roller being siuated rearwardly of the tool in the direction of advance of strip F.
Facing the system just described, which is concerned with one edge of the strip, the opposite side of frame 1 carried another system, consisting either of a single roller substantially equidistant from the two fixed rollers 3 and 15, or, better still, as shown, two rollers 16 and 17. The purpose of these rollers 16 and 17 is to apply a thrust to the opposite edge of the strip, so as to ensure that the edge to be cut is at all times in contact with fixed rollers 3 and 15. To that end, the rollers 16 and 17 may be mounted in exactly the same way as those on the side of the edge being cut, but, instead of means such as 5' being provided for locking the roller-holding plate in a slide 5, as in the former case, a free sliding action is provided by spring means, such as, for example, an assembly of spring washers 18 which urge the displaceable rollers 16 and 17 towards fixed rollers 3 and 15 respectively.
One feature of the invention is that plate 1 is free to swing about a fixed vertical pivot 21. This fixed pivot can be used for the trimming of strips of various widths. In other words, the position chosen for this pivot may be such that it lies substantially on the longitudinal centre line of a strip of average width, whereas, over a wide range of strip widths, the pivot will no longer lie on this line, but that will not interfere with the proper functioning of the device. It should be noted that the device enables a consant shaving to be removed, whatever the width of the 'strip.
The mode of operation of the device described above will be readily understood. In particular, no matter how the strip F winds within its own plane, the cutter 7 engages with the edge to be trimmed according to the relative positions of this cutter and of fixed rollers 3 and 15, against which the sheet is constantly held. A continuous shaving is thus removed and automatically discharged through the central opening 2 in frame 1.
Similarly, to trim the other edge of the strip, a second device, numbered generally 22 in FIGURE 3, may be provided. This is the most convenient method where considerations of space are not of paramount importance; for, where the two edges are trimmed by two successive devices, there is no jarring during the passage of the transverse welds necessarily used for joining two strips end to end.
On the other hand, if it is necessary to reduce the amount of space taken up by the equipment, two devices of the kind shown in FIGURE 1 can be combined to form a single installation such as that illustrated diagrammatically in FIGURE 4. In this arrangement, the plate 1 is pivoted at 21 and carries the two rollers 3 and 15, between which is a cutting tool 7, preferably circular and of the rotary type. The rollers and the tool are stationary but can be adjustably fixed in various positions in relation to the plate. The apparatus is completed by a'secend plate 23, which is movable with respect to the first, for example by virtue of its being mounted on suitable slides or articulated at the pivot 21. This second plate 23 carries fixed rollers, '24 and 25, between which is fitted a tool 26, identical to the tool 7. These rollers 24 and 25 and the tool 26 are stationary in relation to this second plate 23, but their position can be varied. In addition, components such as springs 27 or the like, which bear against plate 1, act on the plate 23 so as to thrust the assembly 24/25/26 on one side towards the assembly 3/7/ 15 on the other side. This amounts to saying that the two fixed rollers associated with a tool on one plate have the same function, in relation to the corresponding fixed rollers on the other plate, as that of the moving rollers in the previous case, numbered r16 and 17 in FIGURE 1. This apparatus thus enables both edges of the strip to be trimmed simultaneously,
In addition to trimming the edges, it may be necessary to bring the strip to the same width throughout its length. This can be done with the aid of a device separate from that or those used for the edge trimming. For example, as in the case shown in FIGURE 3, a device such as that numbered generally at may be fitted to follow the two edge trimmers. This device comprises a'plate 31, pivoted at 34. For one of the edges already trimmed, the plate 31 carries two fixed rollers 35 and 36. For the other edge, it carries two displaceable rollers 37 and 38, acted on by resilient means such as springs 39. Between the displaceable rollers 37 and 38, a tool 40 is locked in position. This may be a rotary circular cutter or a simple conventional cutter, since it is working on a readytrimmed face and is thus no longer called upon to cut through the scale that causes such considerable wear.
In this way the tool 40, by acting on one edge at a constant distance from the other edge, which is pressed against the rollers 35 and 36, doe-s indeed produce a strip of constant width. This device 30 may naturally be followed by one or more similar devices, according to the width of shavings having to be removed to produce this constant width.
It is also possible to employ a combination installation with which the edge trimming and width adjustment can be efiected simultaneously. An installation of this kind is shown diagrammatically in FIGURE 5. It comprises a plate 1 pivoted about a fixed point 21, on which plate is mounted a combination of two rollers 3 and 15, between which a cutter 7 is fitted. Facing these fixed rollers are two displaceable rollers 16 and .17, spring-loaded by means such as 18, the assembly being so far identical to that shown in FIGURE 1. In addition, however, a cutter 40' is fixed to plate 1 between the displaceable rollers 16 and .17. It will be apparent that this equipment combines the single edge-trimming device shown in FIGURE 1 with a device for bringing the strip to a constant width, such as the one numbered 30 in FIGURE 3.
In the variant illustrated in FIGURE 6, the plate 41, again has a pivot, 44.
In order to remove shavings which are substantially equal at any given moment from both edges, for the purposes of reducing the strip to a constant width, the plate 41 carries two cutters 45 and 45, each of which cuts one edge of the strip. These should preferably be of the rotary type already described, their position being adjustable but fixed in relation to the plate. Each cutter lies between a trailing roller 46 or 46' respectively, the position of which is adjustable but is fixed in relation to the plate, and a leading roller 47 or 47 respectively which is displaceable relative to the plate.
So that each cutter shall have substantially no more than half the excess width to remove from the strip, the rollers 47 and 47 are carried on arms or levers 48 and 48, which are pivoted at fixed points 49 and 49' respectively and bear toothed sectors 50 and 50 respectively, the sectors being in mesh with each other. In addition, resilient means such as springs 51 and 51 exert a thrust tending to move the displaceable rollers 47 and 47' towards each other.
This toothed sector arrangement is naturally only one example of how the principle can be put into eifect. The specialist will have no difliculty in devising other equivalent means for ensuring that the longitudinal centre line is kept equidistant from the two tools 45 and 45', carried by the plate.
The examples described can naturally be modified in a number of ways without going beyond the scope of the invention.
Thus, for instance, it is possible in all cases to use a conventional fixed cutter instead of the rotary circular one described, though the latter is preferred wherever the tool is called upon to cut through scale. Further variants apart from those described here might also be designed; for example, one edge could be cleaned up with a device such as that shown in FIGURE 1, the other edge being cleaned and the width of the strip made uniform by means of a device of the kind shown diagrammatically at 30 in FIGURE 3.
What is claimed is:
1. A device for trimming at least one edge of a continuously advancing metal strip comprising a plate member displaceable about a pivotal axis, first and second rollers mounted on the plate member in fixed relationship thereto and spaced lengthwise of the direction of advance of the strip for engagement with one longitudinal edge of the strip, a cutting tool mounted on the plate member intermediate said first and second rollers, at least one further roller carried on said plate member and spaced from said first and second rollers in the direction of width of the strip and engageable with the other longitudinal edge of the strip and spring means urging said one further roller towards said first and second rollers to draw said first and second rollers into engagement with said one longitudinal edge of the strip.
2. A device according to claim 1 wherein said first and second rollers are adjustably mounted on said plate memher.
3. A device according to claim 1 wherein said first and second rollers are mounted on said plate member for adjustment in the direction of the width of the strip.
4. A device according to claim 1 wherein the cutting tool is a circular cutter rotatably mounted on the plate member.
5. A device according to claim 4 wherein the shape of the circular cutter is generated as a body of revolution of a conventional cutter.
6. A device according to claim 4 wherein the circular cutter is mounted for rotation about an axis oflset from the general plane of the strip so as to be rotated by engagement with and advancement of the strip.
7. A device according to claim 6 wherein the axis of rotation of the circular cutter is disposed above the general plane of the strip and the plate member is formed with a slot located to receive and permit the escape downwardly of the continuous shaving produced by the cutter.
8. A device according to claim 1 including a second further roller spaced from said one further roller in the direction of advance of the strip and resiliently urged towards said first and second rollers for engagement with said other longitudinal edge of the strip.
9. A device according to claim 8 including a further plate member displaceably mounted on said first-mentioned plate member and spaced from said first and second rollers in the direction of width of the strip, said one and said second further rollers being carried on said further plate member and said further plate member being resiliently urged towards sai-d first and second rollers.
10. A device according to claim 9 including a second cutting tool carried on said further plate member intermediate said one and said second further rollers whereby said one and said other longitudinal edges of the strip may be trimmed simultaneously by said cutting tools.
11. Apparatus for trimming at least one edge of a continuously advancing metal strip comprising at least one device according to claim 1 followed in the direction of advance of the strip by a further device comprising an additional plate member displaceable about a pivotal axis, first and second additional rollers carried on said additional plate member and spaced in the direction of advance of the strip and engageable with one of said one and said other longitudinal edges of the strip, first and second additional further rollers displaceably mounted on said additional plate member and spaced from said first and second additional rollers in the direction of Width of the strip, means resiliently urging said first and second additional rollers into engagement with the other of said one and said other longitudinal edges of the strip and an additional cutting tool disposed between said first and second additional further rollers.
12. Apparatus according to claim 11 including a further cutting tool carried on said plate member and disposed rearwardly of said one further roller considered in the direction of advance of the strip for engagement with said other longitudinal edge of the strip.
13. A device for simultaneously cutting both longitudinal edges of a continuously advancing metal strip comprising a plate member displaceable about a pivotal axis, a pair of opposed guide rollers mounted on the plate member and disposed one on either side of the strip and resiliently urged into engagement with the respective longitudinal edges of the strip, a further pair of opposed rollers disposed rearwardly of the guide rollers considered in the direction of advance of the strip and engageable with the respective longitudinal edges of the strip, and a separate cutting tool disposed between each guide roller and the corresponding one of the further rollers the guide rollers being operable to maintain the longitudinal centre line of the strip equidistant from both cutting tools.
14. A device according to claim 13 wherein a pair of levers is pivotally mounted on the plate member and each lever carries a separate one of the guide rollers, a separate toothed sector is carried by each lever such that said sectors are in mesh with each other and spring means is provided operable to urge the guide rollers towards each other and into engagement with the longitudinal edges of the strip.
References Cited 15 UNITED STATES PATENTS 1,967,262 7/1934 Robinson et a1 83-432 X 2,859,813 11/1958 Klotz 83-412 X 3,110,208 11/1963 Mitchell et a1 83425 X ANDREW R. JUHASZ, Primary Examiner.