SPAIRANI, Roberto (Via De Amicis 27, Mortara, I-27036, IT)
CLAIMS
1. An apparatus for moving a band-shaped product including positioning means suitable for laterally defining the pathway of said band- shaped product, and advance means suitable for moving said band-shaped product along said pathway, characterized in that said positioning means include at least three wheels, each one pivoting about its own axis and provided with a side surface that is suitable to roll over an edge of said band-shaped product, and in that at least two of these three wheels can be translated relative to the third wheel in order to be adapted to different curvatures and different widths of said band-shaped product.
2. The apparatus according to claim 1, characterized in that said three wheels roll over the same edge of said band-shaped product while it is advanced.
3. The apparatus according to any of the preceding claims, characterized in that the axis of said three wheels is perpendicular to said band-shaped product.
4. The apparatus according to claim 2 or claim 3, characterized in that said edge has a linear development and said at least two movable wheels can be aligned with the remaining third wheel along said edge. 5. The apparatus according to claim 2 or claim 3, characterized in that said edge is curved and said at least two movable wheels can be positioned on said edge in order to define, along with the remaining third wheel, a curvilinear path corresponding to the curvature of said edge.
6. The apparatus according to any preceding claim, characterized in that said at least three positioning wheels are mounted idle.
7. The apparatus according to any of the preceding claims, characterized in that said advance means include at least two counter-posed wheels, pivoting about their own axis, with the band-shaped product being sandwiched therebetween, at least one wheel being a driving wheel and foiling over the plane surface of the band-shaped product.
8. The apparatus according to any of the preceding claims, characterized in that the axis of said at least two advance wheels is perpendicular to the axis of said at least three positioning wheels.
9. The apparatus according to any of the preceding claims, characterized in that said positioning wheels and said advance wheels are mounted on supports that can be orientated and translated along the plane. 10. Use of the apparatus according to any of the preceding claims to feed blades for cutting dies to external machines.
11. A machine for blanking and/or bending blades for cutting dies, characterized in that the blades are fed by means of an apparatus according to any of the preceding claims. |
"APPARATUS FOR MOVING BAND-SHAPED PRODUCTS"
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an apparatus for moving band-shaped products, particularly an apparatus for feeding external machines with blades intended for fabricating flat cutting dies and/or rotary cutting dies. BACKGROUND QF THE INVENTION
In various fields of the art, band-shaped products are required to be moved to treating systems, such as machinery or apparatuses adapted to carry out suitable processing or specific treatments.
By the term "band-shaped" is meant a product that is provided with a negligible dimension relative to the other two. Generally, a band-shaped product is provided with a negligible thickness relative to the width and length thereof. Generally, a band-shaped product has a plane surface being defined by two edges. For example, cutting dies, bands, laminates, etc. are band-shaped products.
By the term "moving" is meant the series of movements required to be transmitted to a band-shaped product in order to provide feeding the latter to at least one external machine, which is for example intended to carry out a working. Complex movements can be transmitted to the band-shaped product, such as rotational, translational, continuous, intermittent, reciprocating movements (and combinations thereof). Herein below, particular reference will be made to the field of processing blades (or rules) for cutting dies. The invention, however, is not intended to be limited to this technical field, but it can be rather applied to various fields in which the movement of band-shaped elements is provided, as will be appreciated below.
Cutting dies are known to be generally manufactured from a metal sheet, which is called "blade" or "rule". Cutting dies can be "flat", i.e. they can be made with blades having a substantially linear development in order to allow the same to be installed on plane elements, or they can be "rotary", i.e. they can be made from blades having a curved development in order to allow the same to be installed on cylindrical elements. The installation of the blades on the corresponding fiat or cylindrical elements is usually provided by a part of the blades being orthogonally inserted within suitable grooves that are formed in these elements, which are mostly made of wood. The blades for flat and rotary cutting dies are generally subjected to various processings /treatments and thus they require to be fed to one or more machines. For example, straight (for flat cutting dies) or curved (i.e. bent, for rotary cutting dies) blades are known to be fed to bending and/or blanking stations. Normally, the apparatuses used for moving the blades include means for properly positioning the blades relative to a particular machine and means for advancing the blades to the same machine, such as a blanking press. The means for positioning and advancing the blades include wheels that are intended to be abutted against the blade surface. Particularly, the positioning wheels define the pathway of the blade and the advancing wheels, by rotating about their own axis, transmit the desired movement to the blade.
The "flat" or "straight" blades (i.e. those for flat cutting dies) are fed to a machine according to a rectilinear pathway, with a movement that can be continuous, intermittent or reciprocating. In other words, the traditional apparatuses used for moving flat blades transmits the movement to the blades along the axis thereof. For this reason, this apparatus is relatively
easy to manufacture.
On the contrary, traditional apparatuses used for moving the bent blades (i.e. those curved for rotary cutting dies) must take into account the curvature of the blades and the width thereof, Positioning and advancing the blades thus results to be more complicated to carry out than in the above-mentioned case. Also in this case, a complex movement can be transmitted to the blades, such as a rotational, continuous or intermittent movement, etc. Known apparatuses are provided with two pairs of counter-posed wheels, with the blade to be fed to a machine being sandwiched therebetween. The pairs of wheel include a reference wheel for positioning the blade relative to a reference system and a wheel for advancing the blade. The blade is in contact with the wheels at the inner and outer edges thereof. Normally, the reference wheel of the first pair of wheels is abutted against the inner edge of the bent blade, while the advance wheel, counter-posed to the reference wheel, presses on the outer edge of the blade. On the other hand, the reference wheel of the second pair of wheels is abutted against the outer edge of the blade. The second pair of counter-posed wheels is positioned adjacent the machine to be supplied with the bent blade, preferably in correspondence of the machine tools. The first counter-posed pair of wheels is, on the other hand, positioned along the arc of circle defined by the bent blade, away from the first pair of wheels. The position of at least one pair of counter-posed wheels can be changed for the apparatus to be arranged for moving blades having different curvatures. The distance between centres of the wheels in a same pair can be changed in order to accommodate blades having different widths. The advance wheel, by rotating about its own axis, transmits the movement to the blade, which advances along the pathway
being defined by the reference wheels.
The coupling between the advance wheel and the blade edge is often critical. In fact, the contact surface between the wheel and the blade is minimum, and the wheel can slide on the blade. Furthermore, in many applications, the outer edge of the blade is serrated and the advance wheel rolls on the moving teeth, thus resulting in vibrations and imprecision in the blade movement. These drawbacks are a severe limitation to the repeatability of the displacements that are imparted to the blades over time, with clear negative effects on the accuracy of processing or treatments that are carried out by machines located downstream of the moving apparatus. Disadvantageously, with known apparatuses, the fine-adjustment is not a simple task, particularly when variously sized blades are required to be moved. The proper positioning of the counter-posed pairs of wheels is usually carried out by a skilled operator every time a blade is replaced with another blade of different width and/or curvature. The distance between centres of the wheels in a same pair can be only slightly changed to allow inserting blades having different widths (by blade width is meant the distance between the two edges thereof). The precision of the blade advance movement operated by known apparatuses strongly depends on the blade width. In fact, the wheel transmitting the motion rolls over the blade edge. When the blade width is changed, the movement speed ratio will change accordingly. Adjusting this type of apparatuses is thus a delicate operation. Apparatuses traditionally used for moving band-shaped products generally have drawbacks similar to those that can be seen in apparatuses described with reference to the blades for cutting dies. First of all, known apparatuses has the non-negligible drawback that they do not allow feeding external
machines with band-shaped products having a linear development, and band-shaped products having a curvilinear development. For example, blades for flat cutting dies and for rotary cutting dies are traditionally moved by means of different apparatuses. On the other hand, the need has been felt for a long time to have an apparatus that allows feeding linear and curved band-shaped products, such as blades for flat cutting dies and for rotary dies, to external machines.
The object of the present invention is to provide an apparatus for moving band-shaped products, which resolves the drawbacks of traditional apparatuses.
It is also an object of the present invention to provide an apparatus of the above-mentioned type, which allows for an accurate positioning of the band-shaped products and allows feeding the same products to external machines according to movements that can be repeated over time. It is a further object of the present invention to provide an apparatus for moving blades for cutting dies, which allows supplying external machines with straight blades for flat cutting dies and bent blades for rotary cutting dies. It is yet another object of the present invention to provide an apparatus for moving blades for cutting dies, which allows feeding bent blades for rotary cutting dies to external machines, independently of the curvature of the blades, thickness and height of the latter, while providing easy and comfortable fine-adjustment. SUMMARY OF THE INVENTION These objects are achieved by the present invention thanks to an apparatus for moving a band-shaped product including positioning means suitable for laterally defining the pathway of said band-shaped product, and advance
means suitable to move said band-shaped pϊoduct along said pathway, characterized in that said positioning means include at least three wheels, each one pivoting about its own axis and provided with a side surface that is suitable to roll over an edge of said band-shaped product, and in that at least two of these three wheels can be translated relative to the third wheel in order to be adapted to different curvatures and widths of said band- shaped product.
Advantageously, the apparatus according to the present invention allows moving band-shaped products, such as blades for cutting dies, either having a linear development or provided with a curvature (i.e. bent). In other words, due to the fact that at least two positioning wheels are movable relative to the third wheel, the apparatus is adapted to the curvature and width of the band-shaped product, thereby defining the desired pathway both when the band-shaped product is straight, and when it is curved. Preferably, the three positioning wheels roll over the same edge of the band-shaped product during the advance movement of the latter. Alternatively, the movable wheels roll over one edge of the band-shaped product and the remaining third wheel rolls over the other edge. In both cases, the positioning wheels define the side limits of the pathway of the band-shaped product. The advance direction of the band-shaped product generally coincides with the development direction of the band-shaped product. For example, the band-shaped product is advanced by sliding on a flat guide or rolling on rollers, or by sliding on two flat guides or rolling by being interposed between pairs of rolls. The positioning wheels restrain the lateral displacements (relative to the advance direction) within desired limits or prevent these displacement at all. The position between the wheels can be changed in order to adapt the
apparatus to band-shaped products having different widths. The axis of the three positioning wheels is perpendicular to the band- shaped product, Le. the axis of the wheels is orthogonal to the plane surface of the band-shaped product When the band-shaped product has a linear development, i.e. it is straight, the movable positioning wheels can be aligned with the remaining third wheel along the edge of the band-shaped product. For example, when the band-shaped product is a straight blade for flat cutting dies, the three positioning wheels are in contact with the same edge of the blade, substantially aligned along this edge. The side movements of the blade, relative to the advance direction that is parallel to the length of the same blade, are thus restrained by the three positioning wheels on the one side, and by known guide elements on the other side, such as abutment surfaces. When the band-shaped product has a curvilinear development, i.e. it is provided with a curvature, the movable positioning wheels can be positioned on the curved edge of the product in order to define, in cooperation with the remaining third wheel, a curvilinear path corresponding to the curvature of the edge. For example, when the band-shaped product is a blade for rotary cutting die, the three positioning wheels are in contact with the same edge of the blade along the curvilinear path as defined by the edge itself. The side movements of the bent blade, relative to the advance direction, are thus restrained by the three positioning wheels on the one side, and by known guide elements on the other side, such as abutment surfaces. The apparatus according to the present invention can be thus easily adapted to straight or curved band-shaped products, due to the mobility of said two positioning wheels. The three positioning wheels are preferably assembled idle to the respective
axes thereof in order to minimize the friction with the band-shaped product.
The advance means can be of a traditional type. According to the preferred embodiment of the present invention, the advance means include at least two counter-posed wheels, pivoting about their own axis, with the band- shaped product being sandwiched therebetween. At least one of the two advance wheels is a driving wheel and rolls over the plane surface of the band-shaped product. The driven wheel can be connected to an encoder for the quantitative detection of the displacements that are transmitted to the band-shaped product. The axis of the three advance wheels is perpendicular to the axis of the positioning wheels.
Advantageously, the advance wheels act on the plane surface of the band- shaped product and not on the edges of the latter. This allows the speed ratio to be constant, i.e. the speed ratio does not change when the width of the band-shaped product is changed. It results that the movement transmitted to the band-shaped product is accurate and can be repeated over time, independently of the width of the product. The positioning wheels and advance wheels can be replaced with substantially spherical elements, rolls, etc.. In order to maximize the flexibility of the apparatus, and thus allowing one to move band-shaped products of different sizes and curvatures, the positioning wheels and advance wheels are mounted to supports that can be orientated and translated onto the plane. The fine-adjustment and operation of the apparatus are easy. The position of the positioning wheels is changed such as to arrange the desired pathway according to the size and curvature of the band-shaped product. For example, a control unit in which a suitable software is implemented can
manage the positioning of the wheels. When the band-shaped product is housed in the thus-arranged pathway, the positioning wheels are in contact with the edge of the band-shaped product. The advance wheels are brought in contact to the plane surface of the band-shaped product. The law of the advance movement of the band-shaped product is imposed by the relative wheel being operated by the control unit.
The apparatus according to the present invention allows accurately positioning the band-shaped products along the pathway provided, and allows feeding the products to external machines according to movements that can be repeated over time. The three contact areas between the positioning wheels and the edge of the band-shaped product contribute to form a firm fastening and prevent sideways movements of the product. The advance wheels, unlike what happens with traditional machines, operate on the plane surface of the band-shaped product, with clear advantages for the advance movement precision.
The apparatus according to the present invention can be used with particular benefits in the field of moving blades for cutting dies. Particularly, the apparatus allows feeding blades for flat cutting dies and for rotary dies to external machines, such as blanking and/ or bending stations, independently of the curvature of the blades, thickness and height of the latter.
BRIEF DESCRIPTION OF THE DRAWINGS
Further characteristics and advantages of the present invention will appear more clearly from the description below, which is intended to be illustrative and nbn-Jimiting, with reference to the annexed schematic drawings, in which:
Fig. 1 is a plane view of a traditional apparatus for moving
blades for flat cutting dies and rotary cutting dies; Fig. 2 is a perspective view of an apparatus according to the present invention in a first configuration thereof; Fig. 3 is a side view of the apparatus in Fig. 2; - Fig. 4 is a side view of the apparatus in Fig. 2;
Fig. 5 is a perspective view of the apparatus in Fig. 2; Fig. 6 is a top view of the apparatus in Fig. 2; Fig. 7 is a sectional view of a detail of the apparatus in Fig. 2; Fig. 8 is a top view of the apparatus in Fig. 2; - Fig. 9 is a top view of the apparatus in Fig. 2 in a second configuration thereof; Fig. 10 is a perspective view of the apparatus in Fig. 2 in a third configuration thereof.
MODES FOR CARRYING OUT THE INVENTION Fig. 1 shows an apparatus A that is traditionally used for feeding blades for rotary cutting dies to a blanking and/or bending station. With numeral 1 is designated a bent blade that is fed to the blanking station 2. The blade 1 is advanced along a predetermined pathway according to what is indicated by the arrow F. Practically, the blade 1 moves along a path coincident with the direction of the lengthways development thereof. The positioning of the blade 1 along said path and the advance movement thereof are obtained using positioning wheels and advance wheels. The apparatus A illustrated herein is provided with two positioning wheels 3 and 4 and an advance wheel 5. The blade 1 is sandwiched between the advance wheel 5 and the positioning wheel 3, which are mounted opposite each other. The positioning wheel 4 is mounted opposite a stationary wheel 6. The wheels 3-6 roll over the outer edge 7 and over the inner edge 8 of the blade 1. The
advance wheel 5 transmits the movement to the blade 1 , which advances by being guided by the wheels 3-6.
The outer edge 7 of the blade 1 is usually serrated. The advance wheel 5 rolls over the teeth of the blade 1. The wheel-serrated edge coupling is thus imprecise and causes vibrations which considerably reduce the repeatability of the displacements of the blade 1.
The fine-adjustment of apparatus A is difficult. The distance between centres of the pair of wheels 3, 5 and the distance between centres of the pair of wheels 4, 6 must be manually adjusted by means of suitable mechanisms in order to adapt the apparatus A to the various widths of the moved blades 1. The position of the pair of wheels 3, 5 must be changed relative to the pair of wheels 4, 6 (by means of suitable mechanisms) for the apparatus to be adapted to the various curvatures of the moved blades 1. These operations are time-consuming and must be carried out by a skilled operator. The apparatus does not allow moving straight blades for flat cutting dies, i.e. blades having a linear development.
Fig. 2 is a perspective view of an apparatus B according to the present invention. The apparatus B is provided with a set of advance wheels, which have the function of transmitting the movement to the blade 1, and a set of positioning wheels having the function of precisely guiding the blade 1 along a predetermined pathway.
The set of positioning wheels includes the three wheels 10, 11 and 12. Generally, the positioning wheels can be in a greater number. At least two wheels are movable along the plane relative to the third wheel. In the embodiment shown herein, the wheels 10 and 12 can be translated along the plane relative to the wheel 11. This characteristic, i.e. the mobility of two wheels relative to a third wheel, allows the apparatus B to be adapted
to bent blades 1 having various curvatures as well as to straight blades. The plane along which the positioning wheels 10, 12 move is the horizontal plane as defined by the plane surface IA of the blade 1, i.e. a plane orthogonal to the axis X shown in Fig. 4. The positioning wheels 10-12 roll over an edge 7 or 8 of the blade 1. The contact is provided with the side surface of the wheels 10-12 having vertical axis (parallel to axis X). According to the preferred embodiment of the present invention, the positioning wheels 10-12 are rested on and roll over the same edge 7 or 8 of the blade 1. In the embodiment such as illustrated herein, the wheels 10-12 roll over the inner edge 8 of the bent blade 1.
Alternatively, two positioning wheels can roll over the one edge of the blade 1 and the third wheel can roll over the other edge of the blade. For example, the wheel 11 can run on the outer edge 7 of the blade 1 and the wheels 10 and 12 can run on the inner edge 7. The positioning wheels 10-12 can be associated to an angular encoder, in order to measure the rotation to which the wheels are subjected and for detecting possible deviances from the predefined operating parameters. The positioning wheels restrain the sideways displacements of the blade 1 within a predefined pathway. In the embodiment shown in Fig. 2, die inner edge 8 of the blade runs on the wheels 10-12. The outer edge 7 of the blade 1 can slide on suitable guide surface or can be guided by the wheels 18 and 19.
The vertical displacements of the blade 1 are prevented by suitable vertical centering devices. In the embodiment as illustrated herein, the blade 1 rolls between a pair of rolls 13 and 14, which maintain the blade 1 onto the plane. As best illustrated in Fig. 2 and 7, the apparatus B is further provided with
counter-posed advance wheels 15 and 16, which act in the vertical direction, i.e. roll over the plane surface IA of the blade. At least one of the two wheels is a driving wheel, the other being a driven wheel. The advance wheel 15 is operated by a corresponding motor and transmits the advance movement to the blade 1. Practically, the advance wheel 15 rotates in the direction of arrow R indicated in Fig. 2, thus causing the blade 1 to be displaced in the direction of arrow F. The wheel 16 is associated with an encoder or equivalent position-detecting device. Thereby, the position of the blade can be monitored relative to a reference system and any deviance from predefined operative parameters can be individuated. The advance wheels 15 and 16, having a horizontal axis, support the blade 1 onto the same horizontal plane as defined by the pair of rolls 13 and 14, i.e. the plane of the blade 1 shown in Fig. 7. Advantageously, the advance wheels 15, 16 roll over the plane surface IA of the blade 1, unlike what is provided with traditional machines. The coupling between the wheels 15 and 16 and the blade 1 is thus more precise than the coupling between the advance wheels and the serrated edge of the blade as provided in known apparatus. In fact, the contact area between the wheels 15, 16 and the surface IA of the blade 1 is larger than the contact area between the advance wheel 5 and the edge 7 of the blade as provided in the traditional apparatus A.
The distance between centres of the advance wheels 15 and 16 can be either increased or decreased ("adjustment" movement) in order to accommodate blades 1 having greater or smaller thicknesses. After the blade 1 has been positioned between the pair of rolls 13-14 and the advance wheels 15-16, thus being in contact with the positioning wheel 11, the positioning wheels 10 and 12 are operated by suitable mechanisms
such as to be brought in contact with the same inner edge 8, by adapting themselves to the curvature of blade 1. For example, the wheels 10 and 12 can be each mounted on a support that is movable along the plane relative to the wheel 11 due to suitable gearings. With reference to Figs. 2, 5 and 7-9, the apparatus B is provided with a movable support 30 to which the positioning wheels 10 and 12 are fastened. The positioning wheels 10 and 12 are vertically pivoted on a portion of the support 30. The third positioning wheel 11 is fastened to another support 32, which can be either stationary or adjustable, i.e. movable for a short length in the direction Y (Fig. 7) in order to facilitate the positioning of the blade 1 against the wheel 11. The support 30 (which for clarity is not shown in Fig. 2) is a vertically mounted plate being fastened to a plurality of hydraulic or pneumatic pistons 31, 33. When the travel of the pistons 31, 33 from the surface of the upright 40 is changed, then the distance of the plate 30 from the same surface and the position of the wheels 10 and 12 relative to the wheel 11 are also changed. The gap between the plate 30 and the surface of the upright 40 is designated with W. When the gap W is increased, and pistons 31 and 33 are removed, the positioning wheels 10 and 12 "move backwards" relative to the wheel 11, i.e. they move away from the advance wheel 15 in the direction Y. When the gap W is decreased, and the travel of the pistons 31 and 33 is reduced beyond surface 40, the positioning wheels 10 and 12 "move forward" relative to the wheel 11, i.e. they move towards the advance "wheel 15 in the direction Y. As may be understood from a comparison between Figs. 8 and 9, when the curvature radius of the blade 1 is increased, the gap W is decreased and the positioning wheels 10 and 12 advance relative to wheel 11.
The movement of the movable positioning wheels 10 and 12 can be manually controlled by an operator or the control unit. Preferably, in order to maximize versatility, the apparatus B is also mounted on supports that can be oriented along the plane. Figs. 3-6 illustrate this characteristic. The apparatus B can be translated on the linear guides 20, due to the operation of a motor and a screw 21. The apparatus B can be also oriented along the plane, Le. rotated about the axis X in the direction O. Thereby, the apparatus B can be very easily adapted to variously-sized blades 1. Furthermore, the apparatus B can be oriented to feed either the blade 1 or moved band-shaped product to external machines according to different directions.
Figs. 8 and 9 are top views of the apparatus B being mounted on said movable supports, particularly sliding on the guides 20 and being rotatable according to the angle α. The blade 1 in Fig. 8 has a first curvature, whereas the blade 1 in Fig. 9 has a second curvature, greater than the previous one. Correspondingly, the gap W in Fig. 8 is larger than the gap W in Fig. 9. In fact, the positioning wheels 10 and 12 in Fig. 8 are in a "backward" position relative to the wheel 11, i.e. they are at a greater distance from the advance wheel 15 than wheel 11. Fig. 10 shows the apparatus B according to the present invention as being fine-adjusted in order to move a straight blade 1. The positioning wheels 10 and 12 are substantially "aligned" with the third positioning wheel 11 along the edge 8 of the blade 1. In other words, the three positioning wheels 10- 12 all roll over the edge 8 of the blade. The blade advances in the direction F, i.e. along a rectilinear path, such as towards a blanking station, under the movement transmitted by the advance wheel 15. The sideways displacements of the blade 1 relative to the direction F are prevented by the
wheels 10-12 on the one side, and by the wheels 18, 19, or other surfaces, on the opposite side.
The operation of the apparatus B is easy. The user provides to place the blade 1 as shown in Fig. 1-10, by interposing the blade 1 between the rollers 13 and 14 and between the advance wheels 15, 16 with the edge 8 abutting against the side surface of the positioning wheel 11 (the position of the wheel 11 along the axis Y can be "adjusted", if required). The operator or control unit provides to operate the movable supports of the wheels 10 and 12 (the plate 30) to bring them into abutment against the edge 8 of the blade I 5 which can be bent or straight. In this configuration, the apparatus B is ready to operate. By operating the wheel 15 according to a predetermined motion law, the desired movement is imparted to the blade 1 in the direction F. Generally, the movement can be continuous, reciprocating, intermittent, etc. It is understood that the "setting" or fine-adjustment of the apparatus B results particularly simple and effective at the same time, since the positioning wheels 10-12 can be arranged such as to minimize the clearances between the blade 1 and the wheels 10-12, with clear advantages for the precision and "repeatability " of the advance movement of the blade. The fine-adjustment of the apparatus B further provides the possibility of moving the blades 1, or band-shaped products, having various widths H (Fig. 2) simply by adjusting the position of the positioning wheel 11 in the direction Y and causing the wheels 10 and 12 to move either forward or backward. The fact that the apparatus B can be adapted to various blade widths H is a further advantage over traditional apparatuses, which provides a manual adjustment of the centre between axes of the pair of wheels by a limited
extent, with clear limitations to the maximum height of the blades that can be inserted between the wheels.
Advantageously, the precision of the movement transmitted to the blade 1 is independent of the width H thereof. In fact, the advance wheel 15 rolls over the plane surface IA of the blade 1, and not on an edge 7 or 8 thereof.
The speed ratio is thus constant while the apparatus B is operating, with clear positive effects on fine- adjustment, precision and repeatability of the movement transmitted.
The operation of the apparatus B can be managed by the control unit, in an automated manner. Thereby, the time required for adapting the apparatus B to various blades 1 can minimized.
The apparatus B can be advantageously used for moving band-shaped products of various nature. For example, the apparatus B can move sheets made of metal, plastics, wood, ceramic, etc. For several applications, the positioning wheels can be more than three, such as five or more. Some wheels can be replaced with balls, such as made of ceramics.
Advantageously, the apparatus B according to the present invention allows moving band-shaped products having different curvatures and widths. The positioning wheels, in fact, can be adapted to various curvatures and widths.
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