Roll bending machine
Through the modular hydraulic system and electro-hydraulic linear motion unit, the problems of complex hydraulic system and high energy consumption of existing roll bending machines are solved, and high-precision bending and low-energy consumption of plate and sheet processing are achieved.
Patent Information
- Application Number
- CN202480010295.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-02-01
- Filing Date
- 2024-01-29
- Publication Date
- 2025-09-12
AI Technical Summary
The hydraulic system of the existing roll bending machine is complex, expensive and energy-intensive, complicated to install and adjust, and there is a risk of hydraulic circuit leakage.
A modular hydraulic system uses electro-hydraulic linear motion units and drive units to independently control the position and rotation of each roller, reducing dependence on large hydraulic pumps and electric motors.
It achieves high-precision bending and curving of plates and sheets, reduces energy consumption, simplifies installation and maintenance, and reduces the risk of hydraulic circuit leakage.
Smart Images
Figure CN120641229A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to machines for bending and / or curving plates and sheets of metal and in particular to roll benders commonly known as calenders. Background Art
[0002] A roll bender or calender comprises a plurality of rotating bending rollers or cylinders, typically three or four, through which a plate or sheet, typically made of a metallic material, to be bent, in particular to be curved, passes. Typically, the bending rollers are provided with respective longitudinal axes of rotation parallel to one another and are such that the product, plate or sheet, passing through the bending rollers according to an advance direction orthogonal to said axes of rotation is bent, typically with a set radius of curvature (e.g. to form a cylindrical element).
[0003] A three-roller roll bender consists of an upper roll and two side rolls arranged below and on either side of the upper roll. The side rolls are motorized, meaning they are driven into rotation by suitable drive units during the bending process to apply a torque suitable for pulling and bending the sheet metal. The side rolls can either idle, meaning they rotate freely about their respective axes of rotation, or they can be motorized by means of corresponding drive units.
[0004] The vertical position of the upper roller and / or the position of the side rollers can be adjusted to vary the mutual distance between the rollers depending on the size and / or thickness of the board or sheet and the bending / curving to be performed.
[0005] A four-roller roll bender consists of an upper roller, a lower roller located below, and two side rollers, all of which rotate about respective longitudinal rotation axes that are parallel to each other. The upper and lower rollers are motorized and allow the plate or sheet to be clamped or "clamped" as it moves along the forward direction, while the side rollers keep the plate or sheet flat, i.e., the side rollers support the plate or sheet at the bottom and guide it in a controlled manner as it enters and leaves the upper and lower rollers. The upper and lower rollers are usually rotated by separate respective drive units in order to apply the corresponding bending torque to the plate or sheet. The side rollers are in an idle state, i.e., they rotate freely about their respective rotation axes.
[0006] The lower roller can be moved vertically toward or away from the upper roller, while the upper roller is generally fixed in position. The side rollers can move along an inclined direction or along an arc-shaped trajectory relative to the upper and lower rollers. The position of the lower and side rollers can be adjusted depending on the size and / or thickness of the plate or sheet and the bend / curve to be performed on the plate or sheet.
[0007] In both types of bending machines - with three or four rollers to rotate the bending rollers and / or move the bending rollers to adjust the position of the bending rollers - hydraulic actuators are used, which can provide the high torque and / or compression / traction forces required to bend and curve plates and sheets that may have high thickness and dimensions.
[0008] In particular, hydraulic rotary motors are used to rotate the motorized rollers about their respective longitudinal rotation axes, while hydraulic cylinders or jacks are used to move the rollers linearly to adjust their positions relative to each other.
[0009] Hydraulic cylinders are also used to rotate and disengage the support element (yoke) from one end of the upper roller to allow the bent product to be removed laterally from the bender.
[0010] Thus, the known roll bending machine comprises a hydraulic system adapted to supply and control rotary motors and hydraulic cylinders. The hydraulic system generally comprises: one or more hydraulic pumps operated by corresponding rotary electric motors provided with a speed reducer; a tank for hydraulic fluid; a plurality of valves for controlling the flow of hydraulic fluid under pressure to and from the actuator; and a hydraulic circuit formed by a plurality of pipes and tubular members adapted to connect the pump to the actuator and to convey high-pressure hydraulic fluid from the pump to the actuator and vice versa.
[0011] A disadvantage of such known roll bending machines is that the corresponding hydraulic system is quite complex and expensive and requires large electric motors and pumps to be able to supply a plurality of hydraulic actuators. In addition, the size of the hydraulic circuit connecting all actuators requires a large amount of hydraulic fluid.
[0012] The installation and adjustment of the hydraulic system is also complicated, and the hydraulic system is quite bulky.
[0013] Finally, due to the power of the one or more electric motors required to drive the one or more large hydraulic pumps, this type of hydraulic system consumes a large amount of energy, even when only one hydraulic actuator has to be operated. Summary of the Invention
[0014] The object of the present invention is to improve known roll bending machines, in particular three-roll or four-roll bending machines, which are suitable for bending and / or curving metal sheets and plates.
[0015] Another object is to provide a roll bender that is capable of bending and curving plates and sheets with a high degree of precision and accuracy while at the same time enabling the energy consumption required for the operation of the roll bender to be significantly reduced.
[0016] Another object is to provide a contra-angle bender that is easy to assemble and install and that is equipped with a modular and simplified hydraulic system.
[0017] These and other objects are achieved by a roll bending machine according to one or more of the claims set out below. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The invention may be better understood and implemented with reference to the accompanying drawings, which show exemplary and non-limiting embodiments, in which:
[0019] - Figure 1 is a perspective view of a four-roller or drum-type roll bender of the present invention, particularly showing a first side portion of the bender;
[0020] - Figure 2 yes Figure 1 Another perspective view of the roll bender, particularly showing an opposite second side of the bender;
[0021] - Figure 3 yes Figure 1 A front view of the contra-angle machine;
[0022] - Figure 4 yes Figure 1 A projection of a first side portion of the bending machine;
[0023] - Figure 5 yes Figure 2 A projection of a second side of the bending machine;
[0024] - Figure 6 is a hydraulic diagram of the first linear movement unit of the bending machine of the present invention;
[0025] - Figure 7 and Figure 8 They are perspective views of corresponding opposite sides of the three-roller roll bender of the present invention.
[0026] - Figure 9 and Figure 10 They are respectively perspective views of respective opposite sides of a modification of the three-roller roll bender of the present invention. DETAILED DESCRIPTION
[0027] Reference Figure 1, shows a so-called four-roller roll bender 1 according to the present invention, which is suitable for bending and / or curving metal plates and / or sheets and comprises: an upper bending roller or cylinder 2; two side bending rollers or cylinders 3, which are positioned on either side of the upper roller 2; and a lower bending roller 4, which is positioned below the upper roller 2 and between the side rollers 3. The upper roller 2, the lower roller 4, and the side rollers 3 are mounted so as to be rotatable about parallel, respective longitudinal rotation axes X1, X2, and X3. In particular, the upper roller 2 is rotatable about a first rotation axis X1, the side rollers 3 are rotatable about respective second rotation axes X2, and the lower roller 4 is rotatable about a third rotation axis X3.
[0028] The machine 1 further comprises a support structure 5 configured to support the respective opposite ends 2a, 2b, 3a, 3b, 4a, 4b of the upper roller 2, the lower roller 4 and the side rollers 3, and a movement device 6 associated with the support structure 5 and configured to move the lower roller 4 and the side rollers 3 in order to adjust their position and / or orientation relative to the upper roller 2. In particular, the movement device 6 comprises, for each roller 3, 4, two first linear movement units 10 acting on the respective ends 3a, 3b, 4a, 4b of the rollers.
[0029] Reference Figures 1 to 5 In an embodiment of the four-roller roll bender, the moving device 6 includes two first linear moving units 10 associated with each side roller 3 to move the side roller 3 along an arc trajectory, thereby bringing the side roller 3 closer to and lifting it relative to the upper roller 2 and the lower roller 4, or moving the side roller 3 away from and lowering it relative to the upper roller 2 and the lower roller 4.
[0030] The moving device 6 further comprises at least one second linear movement unit 40, which acts on the lower roller 4 to move it linearly, in particular vertically, so as to lift the lower roller 4 and bring it closer to the upper roller 2, or to lower the lower roller 4 and move it away from the upper roller 2. In particular, the second linear movement unit 40 acts on the ends 4a, 4b of the lower roller 4 via suitable transmission mechanisms, which are of known type and are not shown in the figures.
[0031] Alternatively, in a variant of the bender 1 not shown in the figures, the movement device 6 may comprise a pair of second linear movement units 40 each acting on a respective end 4 a , 4 b of the lower roller 4 .
[0032] With particular reference Figure 6, each linear movement unit 10, 40, in particular each linear movement unit 10, 40 of the electro-hydraulic type, comprises: a hydraulic cylinder or jack 11, 11'; a hydraulic pump 15 for supplying pressurized hydraulic fluid (e.g., oil) to the hydraulic cylinder 11, 11'; a rotary electric motor 16, which is arranged to drive the hydraulic pump 15; and a tank 17 for the hydraulic fluid.
[0033] It should be noted that the first linear movement unit 10 and the second linear movement unit 40 differ from each other only in the size of the hydraulic cylinders, since the hydraulic cylinders 11 ′ of the second linear movement unit 40 must be able to apply to the lower roller 4 a very high compression / traction force greater than that required to move the side rollers 3.
[0034] Each cylinder 11, 11' comprises a piston 12 provided with a rod 13 connected to and acting on the respective end of the bending roller. The piston 12 forms inside the housing 14 of the hydraulic cylinder 11, 11' a first chamber 18 and a second chamber 19 supplied by a pump 15.
[0035] Each linear movement unit 10 , 40 further comprises a respective hydraulic circuit 20 provided with pipes 21 - 25 and valves 26 - 30 for connecting the hydraulic cylinders 11 , 11 ′, the pump 15 and the tank 17 in flow connection.
[0036] The hydraulic pump 15 , of known type and not described in greater detail, is a reversible type hydraulic pump suitable for pumping pressurized hydraulic fluid selectively into the first chamber 18 or into the second chamber 19 of the hydraulic cylinder 11 , 11 ′ to allow controlled movement of the piston 12 in two opposite directions or directions of linear movement.
[0037] To this end, the hydraulic pump 15 includes two supply / suction ports 31, 32, each of which is connected to a corresponding chamber 18, 19 of the hydraulic cylinder 11, 11' via a first conduit 21 and a second conduit 22 of the hydraulic circuit 20. In particular, the first supply / suction port 31 is connected to the first chamber 18 of the hydraulic cylinder 11, 11', which is not crossed by the rod 13 of the piston 12, via the first conduit 21, while the second supply / suction port 32 is connected to the second chamber 19 of the hydraulic cylinder 11, 11', which is crossed by the rod 13 of the piston 12, via the second conduit 22.
[0038] Each supply / suction port 31 , 32 of the hydraulic pump 15 is also connected to the tank 17 via a respective third conduit 23 and a respective fourth conduit 24 of the hydraulic circuit 20 .
[0039] The hydraulic circuit 20 further includes: two check valves 26, each of which is inserted in the corresponding third pipe 23 to allow the hydraulic fluid to flow only from the tank 17 to the pump 15 (in the suction state); and two pressure relief valves 27, each of which is inserted in the corresponding fourth pipe 24 to allow the hydraulic fluid to flow only from the pump 15 to the tank 17 when reaching a limited pressure (maximum pressure) at the corresponding port 31, 32 of the pump 15, thereby ensuring that the pressure in the hydraulic circuit 20 does not exceed the set maximum value.
[0040] A filter 33 is inserted in the common end of the two third pipes 23 to filter any impurities present in the hydraulic fluid sucked from the tank 17 .
[0041] The hydraulic circuit 20 further includes a first sequence valve 28 and a second sequence valve 29 respectively inserted in the first conduit 21 and the second conduit 22. More specifically, the first sequence valve 28 is interposed in the first conduit 21 between the first chamber 18 of the cylinder 11, 11' and the pump 15, and is configured to allow the hydraulic fluid to flow freely from the pump 15 to the first chamber 18 and to allow the hydraulic fluid to flow from the first chamber 18 to the pump 15 only when the pressure in the first chamber 18 is substantially equal to the pressure in the second conduit 22, which is located downstream of the pump 15 and almost at the second supply / suction port 32. Similarly, a second sequence valve 29 is interposed in the second conduit 22 between the second chamber 19 of the cylinder 11, 11' and the pump 15, and is configured to allow hydraulic fluid to flow freely from the pump 15 to the second chamber 19, and to allow hydraulic fluid to flow from the second chamber 19 to the pump 15 only when the pressure in the second chamber 19 is substantially equal to the pressure in the first conduit 21, which is located downstream of the pump 15 and almost at the first supply / suction port 31.
[0042] The hydraulic circuit 20 further includes a drain valve 30 interposed in the fifth conduit 25 connecting the first conduit 21 with the tank 17, and in particular, connecting in flow communication a portion of the first conduit 21 disposed between the pump 15 and the first sequence valve 28 with a portion of the fourth conduit 24 downstream of the corresponding pressure relief valve 27. The drain valve 30 is selectively operable to open or close the fifth conduit 25 and, thereby, permit or prevent the flow of hydraulic fluid from the first conduit 21 to the tank 17.
[0043] The discharge valve 30 is, for example, a hydraulic valve of a known type, a two-way, two-position electrically operated valve.
[0044] The hydraulic circuit 20 further includes two pressure sensors 34, which are positioned on the first pipe 21 and close to the first chamber 18 of the cylinders 11 and 11', and on the second pipe 22 and close to the second chamber 19 of the cylinders 11 and 11'. The two sensors 34 are connected to the control unit 50 of the bending machine 1 to transmit the values of the pressure inside the two chambers of the cylinders to the control unit, thereby performing feedback control on the cylinder 11 and adjusting the force applied by the rollers to the sheet or plate to be bent.
[0045] The support structure 5, which is of known type and therefore not described in detail, comprises a first portion 51 and a second portion 52, which are parallel and spaced apart from each other and support the opposite ends of the bending roller. The first portion 51 and the second portion 52 are connected and joined to each other by a base member 53.
[0046] The support structure 5 further comprises a support element 54, a so-called yoke, which is configured to rotatably support the respective end 2a of the upper roller 2 in an operating position W. The support element 54 is of known type fixed in such a way that it can rotate about an oscillation axis Y, in particular being rotatably coupled to the second portion 52 of the support structure 5 so as to be rotatable between an operating position W, in which it engages and supports the end 2a of the upper roller 2, and a non-operating position (not shown in the figures) in which it is disengaged from the respective end 2a of the upper roller 2 in order in particular to allow the bent product, i.e. a plate or sheet, to be removed laterally from the bender.
[0047] The oscillation axis Y is approximately horizontal and orthogonal to the rotation axes X1 , X2 , X3 of the bending rollers.
[0048] The movement device 6 is configured to rotate the support element 54 between an operative position and an inoperative position and, for this purpose, comprises a corresponding linear movement unit 10 associated with the support structure 5 and acting on the support element 54. In particular, the housing 14 of the cylinder 11 is rotatably fixed to the second portion 52 of the support structure 51, while the free end 13a of the rod 13 of the piston 12 of the cylinder 11 is rotatably fixed to the support element 54.
[0049] The control unit 50 of the roll bender 1 is also connected to the linear movement units 10 , 40 and is configured to control the linear movement units 10 , 40 and to adjust the position and / or orientation of the bending rollers 2 , 3 , 4 .
[0050] The roll bender 1 further comprises a drive device 7 arranged to rotate the upper roll 2 and the lower roll 4, in particular the drive device 7 is arranged to rotate the upper roll 2 and the lower roll 4 about respective rotation axes X1 , X3.
[0051] The drive device 7 comprises two drive units 8 which are associated with the support structure 5 , in particular fixed to the first portion 41 of the support structure 5 and configured to rotate the upper roller 2 and the lower roller 4 separately and independently.
[0052] Each drive unit 8 , in particular each drive unit of the electric type, comprises a respective rotary electric motor 36 which is connected via a reduction gear 37 to the respective bending roller 2 , 4 and acts on the respective bending roller 2 , 4 .
[0053] The control unit 50 is also connected to the drive unit 8 of the drive device 7 and is configured to control the drive unit 8 of the drive device 7 to adjust and control the angular position and / or rotation speed of the upper roller 2 and the lower roller 4 .
[0054] The operation of the roll bender 1 of the present invention includes: rotating the upper bending roller 2 and the lower bending roller 3 about their respective longitudinal rotation axes X1, X3 to clamp and pull the plate or sheet to be bent / curved. The plate is inserted between the upper bending roller 2 and the lower bending roller 4; in particular, the plate is inserted between the upper bending roller 2 and the lower bending roller 4 by placing the plate on one of the side rollers 3; in particular, the plate is inserted between the upper bending roller 2 and the lower bending roller 4 by placing the plate on the side roller 3 located upstream with respect to the advancing direction, which is substantially orthogonal to the rotation axes X1, X2, X3 of the bending rollers.
[0055] In order to rotate the upper roller 2 and the lower roller 4 , the two drive units 8 of the drive device 7 are activated and controlled by the control unit 50 .
[0056] Before the bending process, the relative position of the lower roller 4 is adjusted by appropriately operating the moving device 6 , particularly the second linear moving unit 40 , based on the thickness of the plate.
[0057] Likewise, the position of the side rollers 3 relative to the upper rollers 2 and lower rollers 4 may be individually and independently modified before and / or during operation in order to bend and / or curve the sheet in a desired manner.
[0058] To this end, the pairs of first linear movement units 10 associated with the respective side rollers 3 are operated by the control unit 50 to change the position and / or orientation of each side roller 3 relative to the upper roller 2 and the lower roller 4 .
[0059] The operation of each linear movement unit 10, 40 is such that the respective rotary electric motor 16 is enabled to drive the corresponding hydraulic pump 15, in particular in a rotational direction that allows the pump 15 to supply pressurized hydraulic fluid into the desired hydraulic cylinder 11, 11' chamber to move the piston 13 as required.
[0060] More specifically, the rotary electric motor 16 rotates in a first direction so that the pump 15 distributes pressurized fluid from the first port 31 to supply the first chamber 18 of the cylinder 11, 11' through the first pipe 21, thereby extending the piston 12 and the rod 13 of the piston 12 to, for example, lift the corresponding bending roller (the lower roller 4 or the side roller 3).
[0061] In this step, the first sequence valve 28 allows the hydraulic fluid to flow freely from the pump 15 to the first chamber 18 .
[0062] During rotation, the pump 15 also sucks in hydraulic fluid flowing out of the second chamber 19 of the cylinder 11, 11' through the second supply / suction port 32 and delivers the hydraulic fluid to the first chamber 11. To this end, the second sequence valve 29 allows the hydraulic fluid to flow from the second chamber 19 to the pump 15 and therefore to the first chamber 18 only when the pressure in said second chamber 19 is substantially equal to the pressure in the first duct 21, in order to prevent the piston 13 from suddenly emptying the second chamber 18 (thereby pushing the pressurized fluid towards the tank 17), for example under the weight of the relevant bending roller, i.e. to prevent the piston 13 from moving in an uncontrolled and dangerous manner, for example under the weight of the relevant bending roller.
[0063] The check valve 26 located on the third conduit 23 of the hydraulic circuit 20 connected to the second supply / suction port 32 actually prevents the flow of fluid from the second chamber 19 of the cylinder into the tank 17 .
[0064] If the rotary electric motor 16 rotates in the opposite second direction, the pump 15 delivers pressurized fluid from the second port 32 to supply the second chamber 19 of the cylinder 11 , 11 ′ through the second conduit 22 , thereby retracting the piston 12 and the associated rod 13 to lower the bending rollers 3 , 4 .
[0065] In this step, the second sequence valve 29 allows the hydraulic fluid to flow freely from the pump 15 to the second chamber 19 .
[0066] During rotation, the pump 15 also sucks in hydraulic fluid flowing out of the first chamber 18 of the cylinder 11, 11' through the first supply / suction port 31 and delivers the hydraulic fluid to the second chamber 11. To this end, the first sequence valve 29 allows the hydraulic fluid to flow from the first chamber 18 to the pump 15 and thus to the second chamber 19 only when the pressure in the first chamber 18 is substantially equal to the pressure in the second duct 22, in order to prevent the piston 13 from suddenly emptying the first chamber 18 (thereby pushing the pressurized fluid towards the tank 17), i.e., from moving in an uncontrolled and dangerous manner, for example, under the weight of the relevant bending roller.
[0067] Thus, during rotation, the pump 15 gradually sucks in the hydraulic fluid flowing out of the first chamber 18 of the cylinder 11 through the first supply / intake port 31 in a controlled manner and delivers the hydraulic fluid to the second chamber 19 .
[0068] Additionally, in this case, the check valve 26 located on the third conduit 23 of the hydraulic circuit 20 connected to the first supply / suction port 31 prevents the fluid from flowing from the first chamber 18 of the cylinder 11 into the tank 17 .
[0069] The discharge valve 30 , which is in a normally open position when not activated to connect the first duct 21 to the tank 17 , ensures that, in the event of an incorrect activation of the hydraulic pump 15 , the piston 12 is not moved and in particular is not extended by moving the bending rollers.
[0070] The roll bender 1 of the present invention enables metal sheets and plates to be bent and curved with high precision and accuracy, even if they have a great thickness, while enabling energy consumption during operation of the roll bender 1 to be significantly reduced.
[0071] The movement device 6 actually comprises a plurality of first and second electro-hydraulic linear movement units 10, 40, which are autonomous and can be operated individually and independently, enabling the bending rollers to be moved and displaced with precision and reliability. These linear movement units 10, 40 have reduced energy consumption due to the small size and low power of the corresponding electric motors 16 and pumps 15.
[0072] Similarly, the drive device 7 comprises a plurality of drive units 8 of the electric type which are autonomous and can be operated individually and independently, capable of rotating the bending rollers in a precise and reliable manner and having reduced energy consumption due to the reduced size of the corresponding electric motors 36 .
[0073] Thus, unlike known roll bending machines, the roll bending machine 1 of the present invention does not require a central hydraulic system provided with one or more powerful electric motors driving one or more large hydraulic pumps capable of supplying pressurized fluid to all the linear and rotary actuators that move and rotate the bending rolls. In this way, during operation of the machine of the present invention, the energy consumed is only that required to drive the electric motors of reduced size and power of the linear movement units 10, 40 and the drive unit 8 that are actually used.
[0074] Furthermore, the absence of a central hydraulic system makes it possible to reduce the size and dimensions of the roll bender and, in particular, to simplify and speed up the assembly and maintenance processes.
[0075] Finally, it should be noted that the simplicity of the movement device 6 and the absence of a central hydraulic system result in a reduced risk of malfunctions, in particular of leakages in the hydraulic circuit.
[0076] Figure 7 and Figure 8 The invention shows a so-called three-roller roll bender 1, which is similar to the one described above and in Figures 1 to 6 The difference of the machine shown in FIG is that the three-roller roll bender 1 comprises an upper bending roll 2 and two side bending rolls 3 placed on both sides of the upper bending roll 2. The upper bending roll 2 and the side bending rolls 3 are rotatable about respective longitudinal rotation axes X1, X2 parallel to each other and are supported at opposite ends 2a, 2b, 3a, 3b by a support structure 5.
[0077] The movement device 6 associated with the support structure 5 is configured to move the side rollers 3 so as to allow adjustment of their position and / or orientation relative to the upper roller 2. The movement device 6 comprises, for each side roller 3, two respective first linear movement units 10 acting on the respective ends 3a, 3b of said side roller.
[0078] The first linear moving unit 10 is connected to the Figures 1 to 6 The first linear movement unit 10 is the same as that described for the four-roller roll bender.
[0079] The drive device 7 is arranged to rotate the upper roller 2 and the side rollers 3 and comprises three drive units 8 associated with the support structure 5 and configured to rotate the upper roller 2 and the side rollers 3 individually and independently.
[0080] The drive unit 8 is Figures 1 to 6 The drive unit 8 of the four-roller roll bender described is identical.
[0081] In this variant, the supporting structure 5 of the machine 1 also comprises a supporting element 54 , a so-called yoke, configured to support, in the operating position W, the respective end 2 a of the upper roller 2 in a rotatable manner.
[0082] A support element 54 of known type is fixed so as to be rotatable about an oscillation axis Y (which is substantially horizontal and orthogonal to the axes of rotation X1 and X2 of the bending rollers). In particular, the support element 54 is fixed so as to be rotatable about the oscillation axis Y to the second portion 52 of the support structure 5 so as to be rotatable about the oscillation axis Y, so as to be rotatable between an operative position W and an inoperative position in which the support element 54 is disengaged from the respective end 2a of the upper roller 2 in order in particular to allow the bent product, such as a plate or sheet, to be removed laterally from the bending machine. In particular, the support element 54 is rotated between the two aforementioned operative and inoperative positions by a respective linear displacement unit 10 of the displacement device 6.
[0083] The operation of this variant of the three-roller roll bender of the invention is such that the upper roll 2 and the side bending rolls 3 rotate about respective longitudinal axes of rotation X1 , X2 to draw and then bend the plate or sheet.
[0084] In order to rotate the upper roller 2 and the side rollers 3 , the corresponding drive units 8 of the drive device 7 are activated and controlled by the control unit 50 of the machine 1 .
[0085] The position and / or orientation of the side rollers 3 are individually and independently changed before and / or during operation to bend and / or curve the sheet as required.
[0086] To this end, the pairs of first linear movement units 10 associated with the respective side rollers 3 are operated by the control unit 50 to change the position and / or orientation of each side roller 3 relative to the upper roller 2. In particular, the ends 3a, 3b of the side rollers 3 are moved, for example linearly along an adjustment direction of skew or tilt, according to which the side rollers can be raised and brought closer to the upper roller 2, or lowered and spaced apart from the upper roller 2.
[0087] The specific operation of the first linear moving unit 10 has been referred to Figures 1 to 6 An embodiment of a four-roller roll bender is described.
[0088] Reference Figure 9 and Figure 10 , shows a modification of the three-roller roll bender 1 of the present invention, which is different from the one already described and in Figure 7 and Figure 8The difference of the three-roller roll bender shown in is that the upper bending roller 2 can be moved by the moving device 6 to adjust the position and / or orientation of the upper bending roller 2 relative to the side roller 3. In particular, the upper bending roller 2 can be moved linearly and vertically by the moving device 6 to adjust the position and / or orientation of the upper bending roller 2 relative to the side roller 3.
[0089] To this end, the movement device 6 comprises at least one second linear movement unit 40, which acts on the upper roller 2 to move it linearly, in particular vertically, so as to raise or lower the upper roller 2. In particular, the second linear movement unit 40 acts on the ends 2a, 2b of the upper roller 2 via suitable transmission mechanisms, which are of known type and are not shown in the figures.
[0090] Alternatively, in a variant of the bender 1 not shown in the figures, the movement device 6 may comprise a pair of second linear movement units 40 each acting on a respective end 2 a , 2 b of the upper roller 2 .
[0091] The side roller 3 can also be moved toward and away from the upper roller 2 by the moving device 6. In particular, the side roller 3 can also be moved toward and away from the upper roller 2 by the moving device 6 along a horizontal adjustment direction orthogonal to the rotation axis X2 of the aforementioned side roller 3.
[0092] The movement device 6 comprises, for each side roller 3 , two first linear movement units 10 , which act on the respective end 3 a , 3 b of the side roller 3 .
[0093] The first linear moving unit 10 and the second linear moving unit 40 are connected to the Figures 1 to 6 The first linear moving unit 10 and the second linear moving unit 40 of the four-roller roll bender described are the same.
[0094] The drive arrangement 7 is arranged to rotate the upper roller 2 and comprises a drive unit 8 associated with the support structure 5 .
[0095] The drive unit 8 is Figures 1 to 6 The drive unit 8 of the four-roller roll bender described is identical.
[0096] The support structure 5 of the machine 1 comprises a support element 154 , a so-called yoke, configured to support, in an operating position W, the respective end 2 a of the upper roller 2 in a rotatable manner.
[0097] In this variant, the support element 154 is rotatably fixed to a base element 155, which is slidably connected to the support structure 5, in particular, the base element 155 is slidably connected to the second part 52 of the support structure 5, and the base element 155 is linearly and vertically moved by the second linear movement unit 40 of the moving device 6.
[0098] The support element 154 is rotated between an operative position W and an inoperative position about an oscillation axis Y (being almost horizontal and orthogonal to the rotation axes X1 , X2 of the bending rollers) by a respective first linear displacement unit 10 of the displacement device 6 .
[0099] The operation of this variant of the three-roller roll bender of the invention is such that the upper rollers 2 rotate about respective first longitudinal axes of rotation X1 in order to draw and then bend the plate or sheet.
[0100] In order to rotate the upper roller 2 , the corresponding drive unit 8 of the drive device 7 is activated and controlled by the control unit 50 of the machine 1 .
[0101] The position and / or orientation of the upper roller 2 and the side rollers 3 are modified individually and independently before and / or during operation to bend and / or curve the sheet as required.
[0102] To this end, the first linear movement unit 10 and the second linear movement unit associated with the upper roller 2 and the side rollers 3 are operated by the control unit 50 to change the position and / or orientation of each roller 2 , 3 .
[0103] The detailed operations of the first linear moving unit 10 and the second linear moving unit 40 have been described with reference to Figures 1 to 6 An embodiment of a four-roller roll bender is described.
Claims
1. A roll bender (1) for bending and / or curving metal plates and / or sheets, the roll bender (1) comprising: - an upper bending roller (2) and two side bending rollers (3) positioned on either side of the upper bending roller (2), the upper bending roller (2) and the side bending rollers (3) being rotatable about respective longitudinal rotation axes (X1, X2) parallel to one another; - a support structure (5) adapted to support the respective opposite ends (2a, 2b, 3a, 3b) of the upper bending roller (2) and the side bending rollers (3); - a moving device (6) associated with the support structure (5) and configured to move the upper bending roller (2) and / or the side bending roller (3) to adjust the position and / or orientation of the upper bending roller (2) and / or the side bending roller (3), the moving device (6) comprising at least one linear moving unit (10, 40) for each bending roller (2, 3); a control unit (50) connected to at least one of the linear movement units (10, 40) and configured to control at least one of the linear movement units (10, 40) and to adjust the position and / or orientation of the bending rollers (2, 3); Characterized in that each linear movement unit (10, 40) comprises: - a hydraulic cylinder (11, 11') having a piston (12) provided with a rod (13) connected to the end of the bending roller (2, 3) and acting on said end of the bending roller (2, 3); - a hydraulic pump (15) for supplying pressurized hydraulic fluid to the hydraulic cylinders (11, 11'); - a rotary electric motor (16) arranged to drive the hydraulic pump (15); - a tank (17) for said hydraulic fluid; - a hydraulic circuit (20) provided with pipes (21-25) and valves (26-30) to connect the hydraulic cylinders (11, 11'), the hydraulic pump (15) and the tank (17).
2. The roll bending machine (1) according to claim 1, wherein The hydraulic pump (15) is of reversible type and is suitable for delivering pressurized hydraulic fluid selectively into a first chamber (18) or into a second chamber (19), the first chamber (18) and the second chamber (19) being formed in the housing (14) of the hydraulic cylinder (11, 11') by the piston (12).
3. The roll bending machine (1) according to claim 2, wherein: The hydraulic pump (15) includes two supply / suction ports (31, 32), each of which is connected to the first chamber (18) and the second chamber (19) of the hydraulic cylinder (11, 11') through a first pipe (21) and a second pipe (22) of the hydraulic circuit (20), respectively.
4. The roll bending machine (1) according to claim 3, wherein: Each supply / suction port (31, 32) of the hydraulic pump (15) is connected to the tank (17) via a respective third conduit (23) and a respective fourth conduit (24) of the hydraulic circuit (20), wherein the hydraulic circuit comprises a check valve (26) and a pressure relief valve (27), each check valve (26) being inserted in a respective third conduit (23) and capable of allowing the hydraulic fluid to flow only from the tank (17) to the pump (15), and each pressure relief valve (27) being inserted in a respective fourth conduit (24) and capable of allowing the hydraulic fluid to flow only from the pump (15) to the tank (17) when a defined pressure at a respective port (31, 32) of the pump (15) is reached.
5. The roll bender (1) according to claim 3 or 4, wherein: The hydraulic circuit (20) includes a first sequence valve (28) inserted in the first pipe (21) connected to the first chamber (18) of the hydraulic cylinder (11, 11'), the first sequence valve (28) being configured to allow the hydraulic fluid to flow freely from the pump (15) to the first chamber (18) and to allow the hydraulic fluid to flow from the first chamber (18) to the pump (15) only when the pressure in the first chamber (18) is substantially equal to the pressure in the second pipe (22).
6. The roll bender (1) according to any one of claims 3 to 5, wherein: The hydraulic circuit (20) comprises a second sequence valve (29) which is inserted in the second pipe (22) connected to the second chamber (19) of the hydraulic cylinder (11, 11'), the second sequence valve (29) being configured to allow the hydraulic fluid to flow freely from the pump (15) to the second chamber (18) and to allow the hydraulic fluid to flow from the second chamber (19) to the pump (15) only when the pressure in the second chamber (19) is substantially equal to the pressure in the first pipe (21).
7. The roll bender (1) according to any one of claims 3 to 6, wherein: The hydraulic circuit (20) includes a discharge valve (30) inserted in a fifth pipe (25), the discharge valve (30) connecting the first pipe (21) with the tank (17) and capable of being selectively driven to open or close the fifth pipe (25).
8. A roll bender (1) according to any preceding claim, wherein The moving device (6) is configured to move the side bending rollers (3) to adjust the position and / or orientation of the side bending rollers (3) relative to the upper bending roller (2), and the moving device (6) includes two first linear moving units (10) for each side bending roller (3), and the two first linear moving units (10) act on the corresponding ends (2a, 2b, 3a, 3b) of the side bending rollers (3).
9. A roll bender (1) according to any preceding claim, wherein The moving device (6) is configured to move the upper bending roller (2) to adjust the position and / or orientation of the upper bending roller (2) relative to the side bending roller (3), in particular, the moving device (6) is configured to move the upper bending roller (2) linearly to adjust the position and / or orientation of the upper bending roller (2) relative to the side bending roller (3), and the moving device (6) includes at least one corresponding second linear moving unit (40), at least one second linear moving unit (40) acting on the upper bending roller (2).
10. The roll bender (1) according to any of the preceding claims, further comprising a lower bending roller (4) capable of rotating about a corresponding longitudinal rotation axis (X3), the lower bending roller (4) being located below the upper bending roller (2) and placed between the side bending rollers (3).
11. The roll bender (1) according to claim 10, wherein: The moving device (6) is configured to move the lower bending roller (4) to adjust the position and / or orientation of the lower bending roller (4) relative to the upper bending roller (2), in particular, the moving device (6) is configured to move the lower bending roller (4) linearly to adjust the position and / or orientation of the lower bending roller (4) relative to the upper bending roller (2), and the moving device (6) includes at least one corresponding second linear moving unit (40), at least one second linear moving unit (40) acting on the lower bending roller (4).
12. The roll bender (1) according to claim 11, wherein The control unit (50) is also connected to the second linear movement unit (40), and the control unit (50) is configured to control the second linear movement unit (40) and adjust the position and / or orientation of the lower bending roller (4).
13. A roll bender (1) according to any preceding claim, comprising a drive device (70) arranged to rotate the upper bending roller (2) and / or the side bending roller (3), the drive device (7) comprising a drive unit (8) for each bending roller (2, 3) to be rotated, the drive unit (8) being associated with the support structure (5) and being configured to rotate the bending rollers (2, 3) individually and independently.
14. The roll bender (1) according to claim 10 or 11, comprising a drive device (7), which is arranged to rotate the upper bending roller (2) and / or the lower bending roller (4), and the drive device (7) comprises a drive unit (8) for each bending roller (3, 4), which is associated with the support structure (5) and is configured to rotate the bending rollers (2, 4) individually and independently.
15. The roll bender (1) according to claim 13 or 14, wherein: The drive unit (8) comprises a respective rotary electric motor (36) which is connected to the respective bending roller (2, 3, 4) via a reduction gear (37) and acts on the respective bending roller (2, 3, 4).
16. Roll bending machine (1) according to any of the preceding claims, wherein The support structure (5) comprises a support element (54; 154) adapted to rotatably support the respective end portion (2a) of the upper bending roller (2) in an operating position (W), the support element (54; 154) being rotatable about an oscillation axis (Y) in a non-operating position, in which the support element (54; 154) is disengaged from the respective end portion (2a) of the upper bending roller (2), in particular to allow the bent product to be removed laterally from the roll bender, the moving device (6) being configured to rotate the support element (54; 154) between the operating position and the non-operating position, and the moving device (6) comprising a respective first linear moving unit (10) associated with the support structure (5) and acting on the support element (54).