Bending Machine And Method For Processing A Workpiece By Means Of A Bending Machine
20220379366 · 2022-12-01
Assignee
Inventors
Cpc classification
B21D5/02
PERFORMING OPERATIONS; TRANSPORTING
B21D55/00
PERFORMING OPERATIONS; TRANSPORTING
F16P3/02
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B21D5/04
PERFORMING OPERATIONS; TRANSPORTING
F16P3/144
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
B21D55/00
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A bending machine, in particular a swivel bending machine, is provided that defines a safety-relevant work area in which an operator of the bending machine is present during its operation, loading, unloading or the like, having a safety module comprising a safety barrier which provides a variable-size shield for the safety-relevant work area such that a shut-off state and an access state can be generated, wherein in the shut-off state access to the safety-relevant work area is at least partially restricted and wherein in the access state access to the safety-relevant work area is at least partially granted. A method is provided for processing a workpiece by means of a bending machine.
Claims
1-28. (canceled)
29. A bending machine which defines a safety-relevant work area in which an operator of the bending machine is present during its operation, loading, unloading or the like, wherein the safety-relevant work area is the area in front of the bending machine which at least uninvolved and/or unauthorized and/or non-instructed persons must not enter during a bending process for safety reasons, having a safety module, the bending machine comprising: a safety barrier which is at least one selected from the group consisting of (i) planar and (ii) plate-shaped, which is retractable and extendable, and which provides a variable-size lateral shield for the safety-related work area such that a shut-off state and an access state can be generated, wherein in the shut-off state access to the safety-relevant work area is at least partially restricted and wherein in the access state access to the safety-relevant work area is at least partially granted.
30. The bending machine according to claim 29, wherein the safety module comprises a linear guide for the safety barrier.
31. The bending machine according to claim 29, wherein the safety module comprises a spring element that at least one selected from the group comprising (i) supports a movement of the safety barrier and (ii) damps a movement of the safety barrier.
32. The bending machine according to claim 29, wherein a part of the safety barrier, which forms the variable-size shield, is free-floating in the shut-off state.
33. The bending machine according to claim 29, wherein the safety module comprises a drive unit for the safety barrier, which is adapted to move the safety barrier.
34. The bending machine according to claim 33, wherein the drive unit comprises a traction drive including a closed rotating traction mechanism.
35. The bending machine according to claim 33, wherein the safety module comprises a control unit adapted to control the drive unit depending on a force applied to the safety barrier by an operator.
36. The bending machine according to claim 29, further comprising a release unit adapted to prevent or permit a bending process depending on at least one release signal, wherein the safety module is adapted to generate a release signal for the release unit depending on whether or not the shut-off state prevails.
37. The bending machine according to claim 36, wherein the safety module comprises an optical detection unit and is adapted to generate a release signal for the release unit depending on a detection signal of the optical detection unit.
38. The bending machine according to claim 37, wherein at least one component of the optical detection unit is arranged on the safety barrier in such a way that the component moves along with the safety barrier.
39. The bending machine according to claim 29, wherein the safety module comprises a second safety barrier arranged opposite the safety barrier.
40. Bending machine according to claim 29, wherein the shield is pivotably mounted about a pivot axis that extends vertically.
41. The bending machine according to claim 40, wherein the safety module comprises a base plate on which the shield is pivotally mounted.
42. The bending machine according to claim 40, wherein the safety module comprises a roller that supports the shield during pivoting and is spaced from the pivot axis.
43. Bending machine according to claim 40, wherein the shield, in a pivot state, clears lateral access to both the safety-relevant work area and a workpiece holder of the bending machine, wherein the shield is movable to a non-pivot position in which at least one selected from the group consisting of (i) the shut-off state and (ii) the access state, are producible.
44. The bending machine according to claim 32, wherein the part of the safety barrier forming the variable-size shield is free-floating in such a way that no floor-arranged guide elements are used.
45. The bending machine according to claim 37, wherein the optical detection unit comprises a light barrier, wherein the light barrier is attached to the safety barrier such that it moves along with the safety barrier, and wherein the safety laser is arranged on a stationary component of the safety module and does not move along with the safety barrier.
46. A safety module for a bending machine according to claim 29.
47. A method for processing a workpiece by means of a bending machine, wherein the bending machine defines a safety-relevant work area in which an operator of the bending machine is present during its operation, loading, unloading or the like, wherein the safety-relevant work area is the area in front of the bending machine which at least uninvolved and/or unauthorized and/or non-instructed persons must not enter during a bending process for safety reasons, wherein the bending machine comprises a safety barrier which is configured in the form of a surface and/or plate, which is retractable and extendable, and which helps to provide a variable-size lateral shield for the safety-related work area, the method comprising: moving the safety barrier to create an access state in which access to the safety-relevant work area is at least partially granted; loading the bending machine with a workpiece; moving the safety barrier to create a shut-off state in which access to the safety-relevant work area is at least partially restricted; and processing the workpiece.
48. A method for processing a workpiece by means of a bending machine according to claim 40, the method comprising: pivoting the shield about the pivot axis, thereby clearing lateral access to a workpiece holder of the bending machine; and loading the bending machine with a workpiece by laterally feeding the workpiece into the workpiece holder.
Description
[0041] Exemplary preferred embodiments of the invention are explained in more detail below with reference to the accompanying drawings, of which:
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[0057] Several aspects of the invention are illustrated below. In addition, the exemplary embodiments of the invention are exemplified with a specific number of modules, elements and units as well as for a specific embodiment of the invention. For the skilled person, it will be obvious that the presented features as well as their technical effect are transferable to a deviating number and/or modified embodiments within the scope of the claims. Moreover, the skilled person will make useful combinations of the presented features and effects within the scope of the claims.
[0058]
[0059] The bending machine 10 defines a safety-relevant work area 12 in which an operator of the bending machine 10 is present during its operation, loading, unloading, or the like. The safety-relevant work area 12 adjoins the workpiece holder 46 with a first longitudinal side 52, wherein the longitudinal side 52 extends parallel to a transverse direction of the workpiece holder 46. In the present case, the safety-relevant work area 12 extends across an entire width of the workpiece holder 46. The safety-relevant work area 12 has two opposing end faces 54, 56 that extend parallel to end faces of the bending machine 10. In addition, the safety-relevant work area 12 has a second longitudinal side 58 opposite the longitudinal side 52, which establishes a border between the safety-relevant work area 12 and the environment.
[0060] The bending machine 10 includes a safety module 14. The safety module 14 includes a first side wall 60 and a second side wall 62 forming side walls of the bending machine 10. The side walls 60, 62 may be configured as sub-modules of the safety module 14.
[0061] The safety module 14 includes a first safety barrier 16 that provides a variable-size first shield 20 of the safety-relevant work area 12 such that a shut-off state and an access state are producible, wherein in the shut-off state access to the safety-relevant work area 12 is at least partially restricted and wherein in the access state access to the safety-relevant work area 12 is at least partially granted. The first safety barrier 16 is part of the first side wall 60.
[0062] In the following, the function of the safety module 14 is described in more detail with reference to the first side wall 60 and/or the first safety barrier 16 and the first shield. Except for optical components described in more detail below, the second side wall 62 is configured in analogy to the first side wall 60, i.e. in the illustrated case, they substantially are mirror symmetrical. Accordingly, the second safety barrier 18 is configured, mounted and driven in analogy to the first safety barrier 16 (see below).
[0063] In
[0064] The first safety barrier 16 is movable between a retracted position, shown in
[0065] In the shut-off state, the first safety barrier 16 is in a shut-off position in which the first safety barrier 16 blocks lateral access to the safety-relevant work area 12, i.e. access via the first end face 54 of the safety-relevant work area 12. In the access state, the first safety barrier 16 is retracted into an access position so that access via the first end face 54 of the safety-relevant work area 12 is granted.
[0066] The safety module 14 includes a frame 26 that embraces the first safety barrier 16 and guides its movement. The first safety barrier 16 is retractable into or extendable from the frame 26. The safety module 14 includes a linear guide 24 for the first safety barrier 16. In the illustrated case, the frame 26 forms two linear guides 24, 64 that guide the first safety barrier 16 at its bottom and top, respectively. The frame 26 is part of the first side wall 60. The first side wall 60 further comprises cover elements 88, 90 (cf.
[0067] The safety module 14 further comprises a spring element 28 that supports and/or dampens a movement of the first safety barrier 16. In the present case, the spring element 28 is configured as a gas spring. The spring element 28 has a first end that is pivotally secured to the frame 26 and a second end that is pivotally secured to a rear portion 66 of the first safety barrier 16 disposed within the frame 26. When the first safety barrier 16 moves from the access position to the shut-off position, the spring element 28 flips once such that it applies a compressive force on the first safety barrier 16 respectively, urging the first safety barrier 16 into the corresponding position.
[0068] A stop element 70 is arranged on a front strut 68 of the frame 26, which forms a front stop for the first safety barrier 16. This defines the shut-off position of the first safety barrier 16.
[0069] A further stop element 72 is attached to a rear side of the first safety barrier 16, which together with a rear strut 74 of the frame 26 forms a rear stop for the first safety barrier 16. This defines the access position of the first safety barrier 16. The stop element 70 and/or the further stop element 72 may be configured, for example, as a rubber stop.
[0070] The first safety barrier 16 includes a frame element 84 defining an interior space in which various components of the safety barrier 16 and/or the safety module 14 are arranged. A wall element 86 is arranged on at least one side of the frame element 84 and forms an outer surface of the safety barrier 16.
[0071] Two wall elements 86 may also be provided, which cover the frame element 84 from opposite sides and define an interior space for said components together with the frame element.
[0072] In addition, the first safety barrier 16 includes a drag chain 88 to guide cables to electrical and optical components that are movable with the safety barrier 16, such as components of the optical detection unit 40 described below.
[0073] As can be seen in
[0074] The first safety barrier 16 includes a handle 76 attached to a front side of the first safety barrier 16. Via the handle 76, an operator can apply a force to the first safety barrier 16 to move it.
[0075] According to one embodiment of the present invention, the first safety barrier 16 is movable purely mechanically or manually. The spring element 28 may support a movement of the first safety barrier 16 by a force applied by an operator.
[0076] In the illustrated embodiment, however, the safety module 14 has a drive unit 30 for the safety barrier 16. The drive unit 30 comprises an electric motor 78 and a traction drive 32 with a closed rotating traction mechanism 34, such as a belt or a chain. The traction mechanism 34 is permanently connected to the first safety barrier 16 at at least one point so that the safety barrier 16 is pulled along when the traction mechanism 34 rotates upon actuation of the electric motor 78.
[0077] The safety module 14 further comprises a control unit 36 adapted to control the drive unit 30. The control unit 36 may be integrated in a central control unit (not shown) of the bending machine 10, which controls a bending unit of the bending machine 10 during a bending process as well as its drives (not shown). Alternatively, the control unit 36 of the safety module 14 may be connected to the central control unit via an appropriate communication link.
[0078] The control unit 36 controls the drive unit 30 depending on a current operating condition to extend or retract the first safety barrier 16. In the embodiment shown, the control unit 36 is adapted to control the drive unit 30 as a function of a force applied to the first safety barrier 16 by an operator. The safety module 14 is equipped with a suitable force sensor system for this purpose. If the control unit 36 determines, based on a detected actuation force, that the operator is moving the first safety barrier 16, the control unit 36 controls the drive unit 30 to support the movement.
[0079] In the illustrated case, the safety module 14 further comprises a user interface 80 that is configured as a graphical user interface. The user interface 80 may, for example, be configured as a touch display, have a monitor and an input means, etc. Via the user interface 80, an operator may select an operating mode, wherein different operating modes are described in more detail below. Furthermore, a command may be entered via the user interface by means of which the control unit 36 is caused to control the drive unit 30 and move the first safety barrier 16. Thus, an operator may also change the position of the first safety barrier 16 by providing user input via the user interface 80.
[0080] According to one variant of the invention, detection of the force applied by the operator may be omitted. According to this variant, the first safety barrier 16 is only moved in response to user input via the user interface 80.
[0081] As mentioned above, in the illustrated case, the safety module 14 comprises two side walls 60, 62 which are analogous in construction, each having a retractable and extendable safety barrier 16, 18. Generally, the safety barriers 16, 18 are moved parallel to each other. However, for example, in the event that a force applied by an operator is detected at one of the safety barriers 16, 18, only the safety barrier concerned or both safety barriers 16, 18 may optionally be moved. Via the user interface 80, the operator may, for example, preset the corresponding behavior of the safety module 14. In the latter case, the control unit 30 controls the respective drive units of the safety barriers 16, 18 to retract or extend them when a force is detected at a safety barrier. In the first case, only the safety barrier 16, 18 concerned is moved.
[0082] According to the invention, both safety barriers 16, 18 may at least partially be extended at the same time in the shut-off state. However, as noted above, shut-off states may be provided in which only one of the safety barriers 16, 18 is extended or in which the safety barriers 16, 18 are extended to different extents.
[0083] Various safety concepts for releasing a bending process are described below. In the embodiment shown, these safety concepts may be used complementarily or cumulatively. Other embodiments of the invention may use only individual or parts of the described concepts.
[0084] The bending machine 10 comprises a release unit 38, which may be integrated in the central control unit of the bending machine 10 (not shown) or in the control unit 36 of the safety module 14, for example, or configured separately. The release unit 38 is adapted to release a bending process in a release state and to prevent a bending process if there is no release state. For this purpose, the release unit 38 is adapted to determine whether there is a release state on the basis of one or more release signals.
[0085] A first release signal may be generated by an operator via a foot switch 82. The foot switch 82 shown in
[0086] A second release signal may be generated by the safety module 14 based on whether the shut-off state prevails. For example, the second release signal is generated when both safety barriers 16, 18 or at least one of the safety barriers 16, 18 are/is extended.
[0087] A third release signal may be generated by an optical detection unit 40 of the safety module 14. In the illustrated case, the optical detection unit 40 comprises a light barrier 42 and a safety laser 44.
[0088] The light barrier 42 is attached in a front section of the first safety barrier 16 and interacts with opposing components attached in a front section of the second safety barrier 18. The light barrier 42 is configured as a light curtain. Light beams of the light curtain extend parallel to the second longitudinal side 58 of the safety-relevant work area 12, the light beams being arranged vertically one above the other. This enables the light barrier 42 to detect an intrusion into the safety-relevant work area 12 at different heights. The light barrier 42 moves along with the first safety barrier 16 and with the second safety barrier 18.
[0089] The light barrier 42 may define the second longitudinal side 58 of the safety-relevant work area 12. When the safety barriers 16, 18 are only partially extended, the light barrier 42 defines, for example, a smaller safety-relevant work area 12 than when the safety barriers 16, 18 are fully extended.
[0090] The safety laser 44 is attached to the frame 46 and is stationary in relation to it, i.e. the safety laser 44 does not move along with the moving safety barriers 16, 18. The safety laser 44 generates laser beams running parallel to the first longitudinal side 52 of the safety-relevant work area 12, which are arranged at the level of the tool holder 46. The safety laser 44 helps to detect whether an operator or, for example, their hands or fingers are too close to the tool holder 46, which would involve a risk of injury during the bending process.
[0091] In the illustrated case, the safety module 14 is adapted to generate the third release signal only when detection is negative in each of the light barrier 42 and the safety laser 44. Alternatively, the safety module 14 may be adapted to generate a third release signal depending on detection of the light barrier 42 and a fourth release signal depending on detection of the safety laser 44.
[0092] In some embodiments, the safety module 44 may include only the light barrier 42 or only the safety laser 44 or even none of them.
[0093] According to a first safety concept, only the first release signal is retrieved.
[0094] According to a second safety concept, a bending process may be released when there is either the first release signal or a combination of the second release signal and the third release signal. According to this concept, the first release signal generated by the operator causes any detection by the safety module 14 to be ignored. However, if the safety-relevant work area 12 is shut off by the safety barriers 16, 18 and if there is no positive optical detection by the optical detection unit 40, it is concluded that, even in the absence of the first release signal, there are no persons in the safety-relevant work area 12 and that a bending process may be performed safely. In the second safety concept, it will be an advantage if the operator can generate the first release signal from a position outside the safety-relevant work area 12.
[0095] According to a third safety concept, the foot switch 82 is deactivated or not available. In this case, the release of the bending process depends only on the position of the safety barriers 16, 18 and optical detection. According to this safety concept, the operator may enter a release signal via the user interface 80. For this purpose, the user interface is conveniently arranged outside the safety-relevant work area. In this case, the operator provides the information that the bending machine 10 is loaded and the safety-relevant work area 12 is cleared. Subsequently, monitoring of the work area 12 by means of the light barrier 42 and/or the safety laser 44 is sufficient to detect a person re-entering the work area 12.
[0096] The release unit 38 is configured to monitor an ongoing bending process. If at least one of the release signals required for the current safety concept is missing, the release unit 38 stops the ongoing bending process. If at least one of the required release signals is missing before the bending process, the release unit 38 prevents the process from being carried out till the required release signals are available.
[0097] Basically, the bending machine 10 of the shown embodiment may be operated in an automatic mode and in a semi-automatic mode. In this respect, reference is made to the flow chart in
[0098] To process a workpiece, the operator first selects the semi-automatic or automatic mode.
[0099] If the semi-automatic mode has been selected, the operator loads the machine with a workpiece and then enters a release signal, for example via the foot switch 82 and/or the user interface 80. After this, the bending process is carried out.
[0100] The bending process may be monitored by the optical detection unit. This is particularly useful when the operator selects a setting in which the light barrier 42 and the safety laser 44 are used. For this purpose, before releasing the bending process, the operator brings the safety barriers 16, 18 into their shut-off positions and establishes the shut-off state.
[0101] Alternatively, the operator may do without monitoring by the optical detection unit and optionally leave the safety barriers 16, 18 in their retracted positions.
[0102] According to one variant, at least the safety laser 44 is always used. If a person reaches into a beam of the safety laser 44 during the bending process, i.e. comes too close to the workpiece holder 46, the optical detection unit detects this and the safety module 14 stops generating the third or fourth release signal. In this case, the release unit 38 immediately stops the bending process to prevent injuries.
[0103] If, on the other hand, the automatic mode has been selected, the safety barriers 16, 18 are automatically moved into their access positions, i.e. the access state is established. An operator may then enter the safety-relevant work area 12 via its end faces 54, 56, if required.
[0104] When the bending machine 10 has been loaded with a workpiece to be processed, the safety barriers 16, 18 are automatically moved into their shut-off positions, i.e. the shut-off state is established. It is then no longer possible to enter the safety-relevant work area 12 via its end faces 54, 56. In addition, the optical detection unit 40 is activated, i.e. it is monitored if a person enters the safety-relevant work area 12 through the light barrier 42 and if an object or person comes too close to the tool holder 46 and interrupts the safety laser 44.
[0105] Subsequently, the operator may have to acknowledge, e. g. via the user interface 80, that the machine has been loaded and that the safety-relevant work area 12 has been cleared.
[0106] After that, the bending process is performed, which is again monitored by the optical detection unit 40.
[0107] In addition or alternatively, a manual mode may also be provided. This mode may do without monitoring by the optical detection unit 40 so that release is solely effected by the operator entering a release signal.
[0108] The safety concepts described may be implemented with safety barriers 16, 18 that are movable only manually when no drive units are available or when the drive units are deactivated or, as in the illustrated case, when the drive units are activated.
[0109] According to a variant of the invention, several different shut-off positions may be provided for the safety barriers 16, 18, in which the safety barriers 16, 18 are extended by different distances and/or offset relative to one another. The control unit 36 may be adapted to move into the different shut-off positions via the drive unit 30.
[0110] Furthermore, according to a variant of the invention, the spring element 28 and/or the handle 76 may be omitted. The safety barriers 16, 18 may then only be moved by the drive unit 30, especially into any shut-off position.
[0111] In addition, further combinations of release signals are possible. In particular, additional monitoring devices may be provided, such as another light barrier, a laser scanner or several acknowledgement switches for several operators. It may further be provided that information on the proper condition of the bending machine is retrieved in several stages before the release by the operator. In particular, if the safety barriers are moved manually, information may be retrieved for each safety barrier as to whether the user caused it to move into shut-off position.
[0112] In the following, further embodiments of the invention or alternative embodiments are described, primarily explaining the differences between the embodiments. It is understood that components not described or not described in more detail may be omitted or may be like those in the above embodiment.
[0113]
[0114] Similar to the bending machine 10 described above, the alternative bending machine 110 comprises a workpiece holder 146. A safety-relevant work area 112 is defined in front of the bending machine 110. This area may be closed off laterally with the shields 120, 122 by extending the barriers 116, 118.
[0115] The safety module 114 of the present embodiment is characterized in that the shields 120, 122 are pivotally mounted.
[0116] The first side wall 160 and the function of its shield 120 are described in more detail below. The description is transferable to the second side wall 122 and its shield 122. In the illustrated case, the two shields 120, 122 pivot in opposite directions. Some components may therefore be mirrored.
[0117]
[0118] The side wall 160 includes a base plate 194. The base plate 194 defines the attachment point of the shield 120 about which the shield 120 is pivotable. For example, the base plate 194 may be screwed or otherwise secured to an installation surface. In other embodiments, the base plate 194 may be connected to a machine frame of the bending machine 110. In other embodiments, the shield 120 may further be pivotally attached to the machine frame in other ways, such as via suitable support arms, support struts or the like.
[0119] In accordance with the present embodiment, the safety module 114 includes a stop element 200. The stop element 200 is secured to the base plate 194. The stop element 200 defines a non-pivot position of the shield 120. Another stop element may further be provided to define a maximum pivot position. The shield 120 may be lockable in the non-pivot position and/or in a pivot position, in particular in a maximum pivot position.
[0120]
[0121]
[0122] The safety module 114 further comprises a roller 198. The roller 198 is attached to a frame 126 of the first side wall 160. The roller 198 is spaced apart from the support bearing 196 or the first axis of rotation 192. When the shield 120 is pivoted, the roller 198 rolls on an installation surface. Therefore, no additional guide rail or the like is required since the roller 198 supports the shield 120 at the front, its path of movement during pivoting being defined by the connection via the support bearing 196. In other embodiments, guidance may also be provided on a rail and/or in a link or the like.
[0123] According to the present embodiment, the shield 120 is pivotable manually. Alternatively or additionally, a suitable drive may be provided. Such drive may be activated automatically depending on an operating mode and/or in response to user input.
[0124]
[0125] The bending machine 110′ differs from the bending machine 100 in that its safety module 114′ includes two shields 120′, 122′ but only one of them is adapted to pivot. For example, a first side wall 160′ is provided with a pivotable shield 120′, whereas a second side wall 162′ comprises a shield 122′ configured like the shield 22 described in connection with the first embodiment. This allows access to the workpiece holder 146′ of the bending machine 10′ from the side to which the pivotable shield 120′ is attached.
[0126] It is understood that bending machines may also be provided which include several safety modules, wherein individual safety modules in particular each from a single side wall. With regard to their description, reference is made to the above explanations.