|
(11) | EP 3 266 973 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
|
|
|
|
|||||||||||||||||||||||||||
| (54) | PUNCHING MACHINE AND METHOD FOR MAKING VENTILATION HOLES ON ROLLER SHUTTER PROFILES |
| (57) The present invention concerns a punching machine and a method using such a machine
for making ventilation holes on roller shutter profiles, the machine comprising: -
a punch 10 for making ventilation holes V on a roller shutter profile P along a direction
of longitudinal extension X of the profile itself; - two pairs of motorized rollers
21, 22 and 31, 32 arranged upstream and downstream of the punch for moving the profile
P in a movement direction M; and - an electronic control unit 60 of the punch adapted
to control the punch in making ventilation holes according to a predefined program
as a function of the length of the profile fed to the punch and/or as a function of
the length of the profile extracted from the punch. The machine 1 comprises a first
idle wheel 41 arranged upstream of the punch and a second idle wheel 51 arranged downstream
of the punch with respect to the movement direction. Each idle wheel has its own rotation
axis parallel to the rotation axis of the motorized rollers and is adapted to contact
with its own circumferential profile a longitudinal portion of the profile to be dragged
in rotation by the profile itself in its movement through the punch. The machine comprises
for each of said idle wheels an encoder 42, 52 that is suitable to detect the angle
of rotation of the respective idle wheel and is connected to the electronic control
unit 60 to allow the latter to calculate the length of the profile P progressively
fed to or progressively extracted from the punch as a function of the rotation angle
of the idle wheel (41, 51), progressively detected over time.
|
Scope
[0001] The present invention concerns a punching machine and a method for making ventilation holes on roller shutter profiles.
[0002] Advantageously, the punching machine according to the present invention may also be used to make through holes/openings that are different from ventilation holes and to make such through holes/openings both on roller shutter profiles and on Venetian blind profiles.
State of the art
[0003] Punching machines are known in the art for making ventilation holes on roller shutter profiles, these machines having mechanical control and start-stop feed and making holes in the profile after the latter has been cut to the desired measure in length. Similar machines exist to make through holes/openings on profiles for Venetian blinds (comparable in shape and structure to roller shutter profiles).
[0004] For such operation, there are so-called tracking punching machines. More specifically, a tracking punching machine adapted to make ventilation holes (or through holes/openings other than ventilation holes) after cutting the profile comprises:
- a punch with hydraulic or electric actuator;
- a conveyor belt for transporting the profile up to the punch;
- a pair of motorized rollers for feeding the profile into the punch; and
- a pair of motorized rollers for extracting the profile from the punch.
[0005] The execution of ventilation holes (or through holes/openings having different functions than ventilation, such as for passing cables or for housing components or functional devices for the operation of the roller shutter or Venetian blinds) on the profile in terms of position with respect to the ends of the final profile and in terms of the size of the holes themselves is controlled on the basis of a predetermined numerical program and as a function of the length of the profile fed and then extracted from the punch. In particular, it is crucial to prevent the ventilation holes (or through holes/openings, other than ventilation holes) from extending beyond the expected length of the profile once cut. This would in fact mechanically weaken the profile itself.
[0006] Operationally, the length of the profile fed and extracted from the punch is calculated on the basis of the rotation angle of the feed and extraction rollers of the profile. For such purpose, the motor of each pair of rollers is provided with an internal encoder which progressively detects the angle of rotation of the rollers over time and communicates the same to an electronic control unit of the punch.
[0007] This type of punch, however, does not allow ventilation holes (or through holes/openings having different functions than that of ventilation) to be made with micrometric precision. This is essentially due to the fact that the feeding of the profiles (for roller shutters or Venetian blinds) to the punch is not precisely controllable because of slipping to which the movement rollers may be subjected to with respect to the profile. Such slipping is not actually detected by the encoders and therefore inevitably affects the detected value of the profile length fed and extracted from the punch, with a resulting reduction in the precision with which holes are made on the profile itself. The error in the estimate of the length of the fed or extracted profile is on the order of 2-3 mm.
[0008] This operational limit prevents ventilation holes (or through holes/openings other than ventilation holes) from being made with a distance programmable with the precision required on the order of ±0.3 mm or less. Such operational limit also conditions the feed speed of the profile to the punch, imposing a maximum speed limit of 60 m/min. A higher feed speed would, in fact, further reduce the precision in making ventilation holes (or through holes/openings other than ventilation holes).
[0009] There is therefore a need in the industry to increase the precision with which the ventilation holes or other through holes/openings are made.
[0010] There is also a need in the industry to increase the speed with which the roller shutter (or of Venetian blind) profiles are fed to the punches, without nullifying the precision with which the ventilation holes or other through holes/apertures are made.
Presentation of the invention
[0011] Therefore, the object of the present invention is to eliminate in whole or in part the disadvantages of the aforementioned prior art by providing a punching machine for making ventilation holes (or through holes in general) on roller shutter profiles (or in general on blind profiles including Venetian blinds) which allows the precision with which ventilation holes are made to be increased.
[0012] A further object of the present invention is to provide a punching machine for making ventilation holes (or through holes in general) on roller shutter profiles (or on blind profiles in general, including Venetian blinds) which may operate at higher profile feed speeds than those of conventional machines.
[0013] A further object of the present invention is to provide a punching machine for making ventilation holes (or through holes in general) on roller shutter profiles (or on blind profiles in general, including Venetian blinds) which is easy to handle.
[0014] A further object of the present invention is to provide a punching machine for making ventilation holes (or through holes in general) on roller shutter profiles (or on blind profiles in general, including Venetian blinds) which are simple and economical to make.
[0015] A further object of the present invention is to provide a method for making ventilation holes (or through holes in general) on roller shutter profiles (or on blind profiles in general, including Venetian blinds) which allows the precision with which the ventilation holes (or through holes in general) are made to be increased while at the same time operating at a higher profile feed speed.
Brief description of the figures
[0016] The technical features of the invention, according to the above objects, are clearly apparent from the content of the claims below, and the advantages thereof will become more apparent in the following detailed description, made with reference to the accompanying drawings, which represent one or more purely exemplifying and non-limiting embodiments, wherein:
- figure 1 shows a perspective view of an example of a shutter profile with ventilation holes made along a direction of longitudinal extension X of the profile; and
- figure 2 shows a simplified side view of a punching machine according to an embodiment of the invention.
Detailed description
[0017] With reference to the accompanying drawings, a punching machine for making ventilation holes on roller shutter profiles according to the invention is indicated in its entirety at 1.
[0018] Within the scope of the present invention, making through holes/openings other than ventilation holes on a profile presents problems that are all together similar to those encountered when making ventilation holes.
[0019] Moreover, making such through holes (whether for ventilation or not) is no different if made in a roller shutter profile than in a Venetian blind profile. Within the scope of the present invention, Venetian blind profiles are in fact comparable in shape to roller shutter profiles in that they are elongated, i.e. have a predominantly longitudinal extension.
[0020] Advantageously, the punching machine according to the present invention may therefore be used also to make through holes/openings which are different from ventilation holes and may be used to make such through holes/openings in general on elongated profiles of blinds, i.e. both on roller shutter profiles and on Venetian blind profiles.
[0021] The remaining part of the description and the claims will specifically refer to making ventilation holes on roller shutter profiles. This indication should not be construed as limiting, as the creation of through holes/openings in general (even not for ventilation), not only on roller shutter profiles but also on Venetian blind profiles is included. In other words, the making of ventilation holes on roller shutter profiles should be understood as a typical, but not exclusive, embodiment of the invention.
[0022] According to a general embodiment of the invention, as illustrated in figure 2, the punching machine 1 comprises a punch 10 adapted to make ventilation holes V on a roller shutter profile P along a direction of longitudinal extension X of the profile itself, which is parallel to a movement direction M of the profile P through the punch.
[0023] The punch 10 integrated in the punching machine 1 may be of any type suitable for the purpose. In particular, it may comprise one or more punching heads with hydraulic, pneumatic, servo-electric, mechanical or other actuation. It will not be described here in detail as it is well known per se to one skilled in the art.
[0024] The punching machine 1 according to the invention further comprises:
- at least a first pair of motorized rollers 21, 22 opposed to each other, which are positioned upstream of the punch 10 and are adapted to move the profile P in said movement direction M by dragging it between them to feed it to the punch; and
- at least a second pair of motorized rollers 31, 32 opposed to each other, which are positioned downstream of the punch 10 and are suitable to move the profile P in said movement direction M by dragging it between them to extract it from the punch.
[0025] The motorized rollers 21, 22 and 31, 32 may be of any kind suitable to the purpose. They will not be described here in detail as they are well known per se to one skilled in the art.
[0026] The punching machine 1 comprises an electronic control unit 60 of the punch 10 adapted to control the punch when making ventilation holes V (or other through holes/openings different from ventilation holes) on the profile P fed to the punch 10.
[0027] The ventilation holes V (or other through holes/openings different from ventilation holes) are made according to a predetermined hole execution program, as a function of the length of the profile P fed to the punch and/or as a function of the length of the profile P extracted from the punch.
[0028] An example of a roller shutter profile P with ventilation holes V made along the direction of longitudinal extension X is shown in figure 1.
[0029] In particular, the program may be set by defining the size of the holes and their position in the profile P along the direction of longitudinal extension X as a function of the length of the profile P. Advantageously, the hole execution program may be set by a control technician of the punching machine 10 via a suitable user interface or selected from a series of pre-set programs stored in the electronic control unit.
[0030] According to a first aspect of the invention, the punching machine 1 comprises:
- a first idle wheel 41 arranged upstream of the punch 10 with respect to the movement direction M; and
- a second idle wheel 51 arranged downstream of the punch 10 with respect to the movement direction M.
[0031] Each of said two idle wheels 41 and 51 has its own rotation axis parallel to the rotation axis of the motorized rollers 21, 22 and 31, 32 and is adapted to contact with its own circumferential profile a longitudinal portion of the profile P to be dragged in rotation by the profile P itself in the movement of the latter through the punch 10.
[0032] According to a further aspect of the invention, the punching machine 1 comprises, for each of said two idle wheels 41 and 51, an encoder 42, 52, which is suitable to detect the angle of rotation of the respective idle wheel 41, 51 and is connected to the electronic control unit 60 to allow the latter to calculate the length of the profile P progressively fed or progressively extracted from the punch as a function of the angle of rotation of the idle wheel 41, 51 progressively detected over time.
[0033] Due to the invention, and unlike conventional solutions, the detection of the length of the profile P fed or extracted from the punch is performed independently of the operation of the motorized rollers. The detection is therefore no longer affected by any slipping or sliding that the rollers may inevitably be subjected to, thus being much more precise. The idle wheels 41 and 51 are in fact dragged in rotation by the movement of the profile P through the punch and are therefore much less subject to sliding than the rollers, as they do not have to deliver power on the profile itself.
[0035] This allows micro perforation dies to be used on the roller shutter (or Venetian blind) profile P, which typically need these tolerances to give an optically acceptable result.
[0036] Due to the greater precision obtainable with the punching machine according to the invention, numerically controlled punching may be performed, with positioning of holes of different dimensions according to a program.
[0037] The idle wheels 41 and 51 also have a considerably smaller axial dimension than the motorized rollers 21, 22 and 31, 32, given that the wheels - unlike the rollers - do not need to engage the profile P over much of its width, but rather only need to contact the profile in a limited area, enough to drag themselves in rotation. It follows therefore that:
- the idle wheels 41 and 51 have a much smaller mass than the motorized rollers and hence a much lower inertia that reduces the effects of possible slippage; and
- the idle wheels 41 and 51 contact the profile P over a much smaller portion with respect to the rollers, and therefore, in the rotation thereof, the wheels are less affected than the rollers by possible shape variations that the profile may have in its width; this allows the wheels to have a less disturbed, and therefore more regular, movement in rotation.
[0038] The increase in precision is also favored by the fact that the length detection is performed by detecting the angle of rotation of the wheels and not of the rollers.
[0039] According to the embodiment illustrated in figure 1, each of the said two idle wheels 41 and 51 has its own rotation axis independent of the motorized rollers of the first and second pair of motorized rollers 21, 22 and 31, 32. The idle wheels 41 and 51 may be arranged both upstream and downstream of the pairs of motorized rollers.
[0040] In particular, as shown in figure 2, the punching machine 1 may comprise for each of said first and second idle wheels 41, 51 an idle contrast wheel 41b and 51b with a rotation axis parallel to the rotation axis of the respective idle wheel 41 or 51. Each idle contrast wheel 41b and 51b is arranged so as to contact the profile P of the roller blind (or of a Venetian blind) on the opposite side with respect to the first and second idle wheel 41, 51, and exert on the profile P enough thrust to keep the profile in contact with the idle wheel 41 and 51, the rotation of which is detected by the encoder 42 or 52.
[0041] According to an alternative embodiment not shown in the appended figures, the two idle wheels 41 and 51 are supported by the rotation axes of the motorized rollers. More specifically, the aforementioned first idle wheel 41 is coaxial to one of the two rollers of the first pair of motorized rollers 21, 22, whereas the second idle wheel 51 is coaxial to one of the two rollers of the second pair of motorized rollers 31, 32.
[0042] Preferably, each of said first and second pair of motorized rollers 21, 22 and 31, 32 is actuatable in rotation independently of the other pair of motorized rollers by means of its own motor 23, 33. Preferably, such motor 23, 33 is a brushless motor.
[0043] As will be discussed later, the independent actuation of the two pairs of motorized rollers 21, 22 and 31, 32 allows for better adaptation of the feed speed of the profile in the punching machine in the actual operating conditions, thus reducing the risk of slipping or sliding.
[0044] Advantageously, as shown in the appended figures, the punching machine 1 comprises, both upstream and downstream of the punch 10, means 71, 72 for detecting the presence of the profile P along machine 1. Preferably, such detection means are optical presence sensors, in particular, photocells.
[0045] Preferably, the aforementioned electronic control unit 60 is programmed to regulate the movement velocity of the profile P through the punch 10 by acting on the motors 23, 33 of the pairs of rollers.
[0046] Operationally, such regulation is performed as a function of the fact that through said sensing means 71, the profile P is detected to be present on both pairs of rollers 21, 22 and 31, 32 or on only one of them.
[0047] Preferably, said electronic control unit 60 is programmed to:
- increase the angular acceleration of the rollers of both pairs 21, 22; 31, 32 until reaching a predefined maximum movement speed of the profile P, when the profile P is detected to be present on both pairs of rollers; and
- decrease the angular acceleration of the only one pair 21, 22; 31, 32 acting in dragging on the profile until reaching a predefined minimum movement speed of the profile P, when the profile P is detected to be present on one of the two pairs of rollers.
[0048] In the initial stages of feeding the profile P to the punching machine, when the profile P is beginning to enter the machine and has not yet passed the punch with its head portion, the regulation step e) provides that active rollers (i.e., the rollers 21, 22 of the first pair) upstream of the punch have a predefined angular acceleration profile increasing from an initial minimum value.
[0049] The presence of the profile P is controlled by said means 71, 72, which are connected to the electronic control unit 60, to detect the presence of the profile P upstream and downstream of the punch 10.
[0050] Due to the independent regulation of the two pairs of rollers, it is possible to regulate the movement speed of the profile P as a function of the available grip, so as to reduce the risk of slipping and sliding while keeping the machining precision.
[0051] The movement speed of the profile P is increased by increasing the acceleration of the motorized rollers when both pairs of rollers are on the profile, i.e. when the maximum grip is available.
[0052] The movement speed of the profile P is decreased by decreasing the acceleration of the motorized rollers when only one of the pairs of rollers is on the profile, i.e. when the minimum grip is available.
[0053] In this way, due to the punching machine according to the invention, it is possible to reach average feed speeds greater than 80 m/min, without thereby adversely affecting the precision with which the holes are made on the profile P.
[0054] The punching machine 1 may comprise a conveyor belt (not shown in the appended figures) for transporting a roller shutter profile P up to the first pair of motorized rollers 21, 22 upstream from the punch 10.
[0055] The method for making ventilation holes (or through holes/openings other than ventilation holes) on roller shutter (or Venetian blind) profiles will now be described according to the present invention.
[0056] In accordance with a general form of implementation, the method comprises the following operational steps:
- a) providing a punching machine 1 according to the invention, in particular as described above;
- b) feeding said punching machine 1 with a roller shutter profile P by moving the profile P through the punch 10 along said movement direction M by means of one or both of said pairs of motorized rollers 21, 22; 31, 32;
[0057] In particular, in the initial stages of feeding the profile P, when the profile P is beginning to enter the machine and has not yet passed the punch with its head portion, only the rollers 21, 22 upstream of the punch act in dragging. When the profile P has reached the rollers 31, 32 downstream of the punch, the latter also begin to operate in dragging in combination with the rollers 21, 22 upstream. In the final stages of feeding the profile P, when the profile P is no longer engaged by the rollers 21, 22 upstream, only the rollers 31, 32 downstream of the punch act in dragging.
[0058] The method also comprises the following operational steps:
c) detecting over time the length of the profile P fed to the punch and/or the length of the profile P extracted from the punch;
d) controlling by means of the electronic control unit 60 the punch 10 for making ventilation holes V (or through holes/openings other than ventilation holes) on the profile P of a roller shutter (or a Venetian blind) along a direction of longitudinal extension X of the profile parallel to the movement direction M.
[0059] The ventilation holes V (or through holes/openings other than ventilation holes) are made according to a predefined hole execution program, as a function of the length of the profile P fed to the punch and/or as a function of the length of the profile P extracted from the punch.
[0060] In particular, the program may be set by defining the size of the holes and their position in the profile P along the direction of longitudinal extension X as a function of the length of the profile P.
[0061] Advantageously, the hole execution program may be set by a control technician of the punching machine 10 via a suitable user interface or selected from a series of pre-set programs stored in the electronic control unit.
[0062] According to the invention in step c), the detection over time of the length of the profile P fed to the punch and/or the length of the profile P extracted from the punch 10 is performed by progressively detecting over time the angle of rotation of the first and second idle wheels 41, 51 independently from the rotation of the motorized rollers 21, 22 and 31, 32. Such detection is performed for each idle wheel 41, 51 by means of an encoder 42, 52 connected to the electronic control unit 60.
[0063] As previously mentioned, the electronic control unit 60 calculates the length of the profile P progressively fed to or progressively extracted from the punch according to the angle of rotation of the idle wheel 41, 51 detected progressively over time by the encoders 42, 52.
[0064] Preferably, the method comprises a step e) for regulating the movement speed of the profile P through the punch 10 acting on the motors 23, 33 of the roller pairs 21, 22 and 31, 32.
[0065] Such regulation is performed as a function of the fact that the profile P is detected to be present on both pairs of rollers 21, 22 and 31, 32 or on only one of them via the means 71, 72 for detecting the presence of the profile P upstream and downstream of the punch 10.
[0066] In particular, in such step e) of regulating the movement speed of the profile P, the angular acceleration of the rollers of both pairs 21, 22; 31, 32 is increased until reaching a predefined maximum movement speed of the profile P, when the profile P is detected to be present on both pairs of rollers, and the angular acceleration of the rollers of the only one pair 21, 22; 31, 32 acting in dragging on the profile is decreased until reaching a predefined minimum movement speed of the profile P, when the profile P is detected to be present on only one of the two pairs of rollers.
[0067] In the initial steps of feeding the profile P to the punching machine, when the profile P is beginning to enter the machine and has not yet passed the punch with its head portion, the regulation step e) provides that active rollers 21, 22 upstream of the punch have a predefined angular acceleration profile rising from an initial minimum value.
[0069] The punching machine according to the invention allows the precision with which ventilation holes (or through holes/openings other than ventilation holes) are made to be increased with respect to similar conventional machines. In particular, a precision on the order of ±0.3 mm or less may be obtained.
[0070] This allows micro perforation dies to be used on the profile P, which typically need these tolerances to give an optically acceptable result.
[0071] Due to the greater precision obtainable with the punching machine according to the invention, numerically controlled punching may be performed, with positioning of different sized holes according to a program.
[0072] The punching machine according to the invention may operate at higher feed speeds with respect to conventional machines. It is possible to reach average feed speeds greater than 80 m/min, without thereby adversely affecting the precision in making holes on the profile P.
[0073] The punching machine according to the invention is of a simple and economical design, since it envisages the use of components per se available on the market.
[0074] The punching machine according to the invention is ultimately easy to manage through a normal control system, as is apparent from the foregoing description.
1. A punching machine for making holes, in particular ventilation holes, on profiles,
in particular roller shutter profiles, comprising:
and in that it comprises for each of said idle wheels (41, 51) an encoder (42, 52) that is suitable to detect the angle of rotation of the respective idle wheel (41, 51) and is connected to the electronic control unit (60) to allow the latter to calculate the length of the profile (P) progressively fed or gradually extracted from the punch as a function of the angle of rotation of the idle wheel (41, 51) progressively detected over time.
- a punch (10) suitable to make holes, in particular ventilation holes (V), on a profile (P), in particular a roller shutter profile, along a direction of longitudinal extension (X) of the profile itself, which is parallel to a movement direction (M) of the profile (P) through the punch;
- at least a first pair of motorized rollers (21, 22) opposed to each other, which are positioned upstream of the punch (10) and are suitable to move the profile (P) in said movement direction (M) by dragging it between them to feed it to the punch;
- at least a second pair of motorized rollers (31, 32) opposed to each other, which are positioned downstream of the punch (10) and are suitable to move the profile (P) in said movement direction (M) by dragging it between them to extract it from the punch; and
- an electronic control unit (60) of the punch (10), suitable to control the punch in making said holes, in particular ventilation holes (V), onsaid profile (P) according to a predefined program as a function of the length of the profile (P) fed to the punch and/or as a function of the length of the profile (P) extracted from the punch;
characterized in that of comprising a first idle wheel (41) arranged upstream of the punch (10) and a second idle wheel (51) arranged downstream of the punch (10) with respect to said movement direction (M), each of said idle wheels (41, 51) having its own rotation axis parallel to the rotation axes of the motorized rollers (21, 22; 31, 32) and being suitable to contact with an own circumferential profile a longitudinal portion of the profile (P) to be dragged in rotation by the profile (P) itself in its movement through the punch (10),and in that it comprises for each of said idle wheels (41, 51) an encoder (42, 52) that is suitable to detect the angle of rotation of the respective idle wheel (41, 51) and is connected to the electronic control unit (60) to allow the latter to calculate the length of the profile (P) progressively fed or gradually extracted from the punch as a function of the angle of rotation of the idle wheel (41, 51) progressively detected over time.
2. Punching machine according to claim 1, wherein each of said idle wheels (41, 51) has
an own axis of rotation independent from the motorized rollers of said first and of
said second pair of motorized rollers (21, 22; 31, 32) .
3. Punching machine according to claim 2, comprising - for each of said first and second
idle wheel (41, 51) - an idle contrast wheel (41b; 51b) with rotation axis parallel
to the rotation axis of said first and of second idle wheel (41, 51), each idle contrast
wheel (41b; 51b) being suitable to contact the profile (P) on the side opposite to
the first and second idle wheel (41, 51).
4. Punching machine according to claim 1, wherein said first idle wheel (41) is coaxial
with one of the two rollers of the first pair of motorized rollers (21, 22) and wherein
said second idle wheel (51) is coaxial to one of the two rollers of the second pair
of motorized rollers (31, 32).
5. Punching machine according to one or more of the preceding claims, wherein each of
said first and second pairs of motorized rollers (21, 22; 31, 32) is actuatable in
rotation independently of the other pair of motorized rollers by means of its own
motor (23, 33), preferably said motor (23, 33) being a brushless motor.
6. Punching machine according to one or more of the preceding claims, comprising both
upstream and downstream of the punch (10) means (71, 72) for detecting the presence
of the profile (P), preferably said detection means being optical presence sensors.
7. Punching machine according to claims 5 and 6, wherein said electronic control unit
(60) is programmed to regulate the movement speed of the profile (P) through the punch
(10) by acting on the motors (23, 33) of the pairs of rollers, said regulation being
performed as a function of the fact that through said presence detection means (71,
72) the profile (P) is detected to be present on both pairs of rollers, or only on
one of them.
8. Punching machine according to claim 7, wherein said electronic control unit (60) is
programmed to:
- increase the angular acceleration of the rollers of both pairs (21, 22; 31, 32) until reaching a predefined maximum movement speed of the profile (P), when the profile (P) is detected to be present on both pairs of rollers; and
- decrease the angular acceleration of the only one pair (21, 22; 31, 32) acting in dragging on the profile until reaching a predefined minimum movement speed of the profile (P), when the profile (P) is detected to be present on one of the two pairs of rollers.
9. Punching machine according to one or more of the preceding claims, comprising a conveyor
belt for the transport of a roller shutter profile (P) up to the first pair of motorized
rollers (21, 22).
10. Method for making holes, in particular ventilation holes, on profiles, in particular
roller shutter profiles, comprising the following operating steps:
a) arranging a punching machine (1) according to one or more of the preceding claims;
b) feeding said punching machine (1) with a profile, in particular a roller shutter profile (P), by moving said profile (P) through the punch (10) along said movement direction (M) by means of one or both of said pairs of motorized rollers (21, 22; 31, 32);
c) detecting over time the length of the profile (P) fed to the punch and/or the length of the profile (P) extracted from the punch;
d) controlling, by means of said electronic control unit (60), the punch (10) to make holes, in particular ventilation holes (V), on said profile (P), in particular roller shutter profile, along a direction of longitudinal development (X) of the profile parallel to said movement direction (M), according to a predefined hole-making program as a function of the length of the profile (P) fed to the punch and/or as a function of the length of the profile (P) extracted from the punch;
characterized in that in step c) the detection over time of the length of the profile (P) fed to the punch and/or the length of the profile (P) extracted from the punch (10) is performed by progressively detecting over time the rotation angle of said first and second idle wheel (41, 51) independently of the rotation of the motorized rollers (21, 22; 31, 32), said detection being performed for each idle wheel (41, 51) by means of an encoder (42, 52) connected to said electronic control unit (60).11. Method according to claim 10, comprising a step e) of regulating the movement speed
of the profile (P) through the punch (10) by acting on the motors (23, 33) of the
pairs of rollers (21, 22; 31, 32), said regulation being performed as a function of
the fact that the profile (P) is detected to be present on both pairs of rollers,
or only on one of them through said means (71, 72) for detecting the presence of the
profile (P) upstream and downstream of the punch (10).
12. Method according to claim 11, wherein in said step e) of regulating the movement speed
of the profile (P), the angular acceleration of the rollers of both pairs (21, 22;
31, 32) is increased until reaching a predefined maximum movement speed of the (P),
when the profile (P) is detected to be present on both pairs of rollers, and the angular
acceleration of the rollers of the only one pair (21, 22; 31, 32) acting in dragging
on the profile is decreased until reaching a predefined minimum movement speed of
the profile (P), when the profile (P) is detected to be present on only one of the
two pairs of rollers.