EP0419344A1 - Metal working machine for flat pieces with improved security - Google Patents

Abstract

The machine, for example a bending press, comprises a vertical frame (20), an upper tool (23) and a lower tool (24) which can move relatively in the vertical direction on the frame (20). The lower tool (24) is associated with a motory displacement means enabling it to be moved towards or away from the upper tool (23) by displacement in a vertical plane in order to carry out the work or to disengage the workpiece (33, 33'). The press also comprises a horizontal table (26) firmly attached to the lower tool (24). A support (29, 29') is placed in an adjustable position on the table (26) by virtue of a guiding means (28, 28') and comprises a part (32) for holding the workpiece (33, 33'), which is adjustable in height. The machine also comprises a means (39) for driving the motory device of the tool (24) which requires the operator to keep both his hands away from the working zone of the machine. <IMAGE>

Description

The invention relates to a metalworking machine for flat parts with improved safety.

The bending or bending of metal products such as flat irons, to obtain parts having a determined profile, is generally carried out using a folding press comprising a vertical frame and two complementary tools mounted on the frame, one above on the other, at least one of these tools being mounted movable so that it can be approached or distant from the second tool.

The flat parts must be introduced between the tools with relative displacement, in a precise position determined by the position of the line of the folding to be carried out.

The positioning and holding of the flat parts during the approach movement of the tools is carried out manually, the operator holding the part can be forced to place his hands in an area very close to the working area of the press , during the approach and folding phases.

The motor means ensuring the displacement of at least one of the tools of the press can be controlled by the foot by means of a pedal, so that nothing physically prohibits the passage and / or the maintenance of the hands of the operator, in the work area, between tools.

This therefore results in risks for the operator and accidents sometimes occur in workshops using such folding presses.

The object of the invention is therefore to propose a metalworking machine for flat parts with improved safety comprising a vertical frame, an upper tool and a lower tool with relative displacement in the vertical direction, arranged one above the other on the frame, at least one of which is associated with a displacement motor means allowing it to be brought closer or away from the second tool by displacement in a vertical plane to carry out the work of the part between the tools or its release, respectively, and a means for controlling the motor means, this machine to avoid any possibility of accident by the operator's hands passing between the tools, to simplify the machine settings, to improve ergonomic working conditions and to increase productivity.

For this purpose, the metalworking machine according to the invention further comprises a horizontal table integral with the lower tool, at least one guide means fixed on the upper face of the table in a direction substantially perpendicular to the plane in which moves the mobile tool and at least one support mounted mobile on the guide means and comprising a part for holding the workpiece, adjustable in height on the support,
and the motor device control means is constituted by a double electrical contactor comprising two elements, the simultaneous manual actuation of which is necessary to ensure that the motor device is put into operation in the direction of bringing the tools together.

• La figure 1 est une vue schématique en pers­pective d'une presse de pliage suivant l'art antérieur.
• La figure 2 est une vue de côté des outils de la presse, pendant une opération de pliage.
• Les figures 3A, 3B et 3C sont des coupes transversales montrant divers profils obtenus par une opération de pliage d'un fer plat.
• La figure 4 est une vue en perspective d'une presse de pliage à sécurité améliorée suivant l'inven­tion avant une opération de pliage.
• La figure 5 est une vue en perspective de la presse suivant l'invention représentée sur la figure 4, à l'issue d'une opération de pliage.

In order to clearly understand the invention, a description will now be given, by way of nonlimiting examples, with reference to the appended figures, of a flat iron folding press according to the known technique and an improved safety folding press according to the invention.

• Figure 1 is a schematic perspective view of a folding press according to the prior art.
• Figure 2 is a side view of the press tools, during a folding operation.
• Figures 3A, 3B and 3C are cross sections showing various profiles obtained by a folding operation of a flat iron.
• Figure 4 is a perspective view of an improved security folding press according to the invention before a folding operation.
• Figure 5 is a perspective view of the press according to the invention shown in Figure 4, after a folding operation.

In Figure 1, we see a folding press generally designated by the reference 1 and having a vertical frame 2 on which are mounted in parallel positions, an upper tool 3 and a lower tool 4 arranged vertically one on the other and between which the folding is carried out.

The upper tool 3 constitutes a punch whose active lower part 3a shown in FIG. 2 is in the shape of a V.

The lower tool 4 constitutes a matrix whose upper end part 4a has a V-shaped groove whose shape corresponds to the shape of the end part 3a of the punch 3.

The punch 3 and the die 4 have an elongated shape and have an identical profile over their entire length.

Depending on the size of the pieces, one or more pieces for which it is desired to bend can be placed simultaneously between the punch and the die in their open position as shown in FIG. 1.

The lower tool 4 constituting the matrix is mounted mobile in a vertical plane parallel to the front of the frame 2 and associated with motor devices such as hydraulic cylinders 5 which can ensure its displacement in the vertical plane, either up or down.

The upward movement of the die 4 makes it possible to bring it closer to the fixed punch 3 in order to fold a flat iron introduced between the punch and the die as shown in FIG. 2.

The flat iron 7 can be placed, when the tools are in their separated position, so as to come to rest on the upper face of the matrix 4a.

An adjustable stop 8 mounted on a support 9 integral with the matrix 4 ensures the establishment of the flat iron 7 on the upper end 4a of the matrix, so as to achieve the bending or folding of the part 7 according to a well-defined line.

The operator manually maintains the flat part 7 on the upper part of the die 4 and in contact with the stop 8, during the approach phase of the tools 3 and 4, until the end 3a of the punch 3 is coming into contact with the upper face of the flat iron 7.

The actual folding operation is then carried out by an additional upward movement (arrow 11) of the die 4, the part 7 being interposed between the punch and the die.

The end 3a of the punch 3 pushes on the part 7, along the desired fold line and achieves the insertion of the part 7 in the V-groove of the part 4a of the die, so as to achieve the bending of the part 7 by a determined angle.

In Figure 2, there is shown in broken lines and under the reference 7 ′, the part 7 after bending. In this case, the bending results in a bending of the part at 90 °.

The reconciliation of parts 4 and 3 and the folding operation are carried out thanks to the hydraulic cylinders liques 5 whose rods exert a thrust in the vicinity of each of the ends of the matrix 4.

The hydraulic cylinders 5 are controlled by a pedal which can be actuated at the foot by the operator, to trigger the movement of movement upwards of the die 4, from the open position of the press shown in FIG. 1 .

The operator generally uses his two hands to hold the part 7 during the approach of the tools, in the position shown in FIG. 2.

Depending on the position of the folding line to be produced, relative to the edge of the part, the operator may have to handle the part in an area very close to the area of action of tools 3 and 4.

In addition, there is no way to prevent the operator from accidentally placing his hands between the tools, when he performs actuation at the foot of the actuator control pedal 5.

Depending on the type of work carried out, the initial positioning of the flat bars on the die, before folding, can be carried out by means of stops as shown in FIG. 2 or by means of marks traced on the flat part and defining the position of the fold line.

In FIGS. 3A, 3B and 3C, different profiles of parts have been shown obtained by folding from flat irons.

In FIG. 3A, we see a part 12 which has been produced by four successive folding operations at right angles to a flat iron.

In FIG. 3B, a part 13 has been shown which has been obtained by three successive folds of a flat iron, at an obtuse angle.

In FIG. 3C, a part 14 has been shown which has been obtained by bending an iron at right angles flat, the edges of which have themselves been folded at right angles towards the interior of the room.

It is understood that the successive production of the folds on the flat irons to produce parts such as 12, 13 and 14, requires carrying out a precise adjustment of the position of the parts before each folding operation and can lead the operator to handle the parts in an area in the immediate vicinity of the tool work area.

In FIGS. 4 and 5, an improved security folding press according to the invention is shown, comprising a vertical frame 20 substantially similar to frame 2 of the machine shown in FIG. 1.

On the front vertical face 21 of the frame is fixed the upper tool 23 produced in the form of a punch having a projecting working end and whose cross section is in the shape of a V. This working part of the punch 23, in the form elongated, has an end edge defining the position of the fold to be produced on a flat part.

The lower tool 24 constitutes a matrix having on its upper face a V-shaped groove whose shape corresponds to the shape of the projecting working part of the punch 23.

The matrix 24 is mounted at the upper end of a support 25 itself mounted movable in the vertical direction, in a plane parallel to the front face 21 of the frame. The punch 23 and the die 24 are located vertically from one another, so that the edge delimiting the working part of the punch is exactly plumb with the bottom of the V-groove of the die 24.

The support 25 of the matrix 24 can be mounted movably on the face 21 of the frame by means of slides of vertical direction. This support 25 is associated with motor means such as hydraulic jacks, not shown, which make it possible to move it in the vertical direction up or down, so as to bring it closer or away from the fixed punch 23.

According to the invention, the support 25 of the die 24 constituting the movable lower tool of the press carries a horizontal table 26 which can be welded and held on the front face of the support 25 by means of brackets 27.

On the upper face of the table 26 are fixed guide rails 28 and 28 ′ parallel to each other and perpendicular to the plane of the support 25 which is itself parallel to the plane of movement of the movable tool 24. The rails 28 and 28 ′ Are therefore perpendicular to the plane of movement of the tool and are fixed substantially over the entire width of the table 26.

On the rail 28 is mounted sliding a support generally designated by the reference 29 comprising a base 30, two vertical slides 31 constituted by columns fixed on the base 30 and a holding device 32 of a flat iron 33 on which performs a folding.

The base 30 has a groove on its underside allowing it to slide along the rail 28.

The holding device 32 includes openings for engaging the columns 31 allowing a sliding mounting of this holding device on the columns and a clamping means (not shown) allowing it to be locked in a determined vertical position.

The device 32 comprises a support 34 having a support flange 35 directed towards the front face of the press and a lateral holding means 36 rigidly fixed on one of the sides of the support 34.

A support device generally designated by the reference 29 ′ and having a structure similar to the device 29 is mounted sliding on the rail 28 ′.

As can be seen in FIG. 4, the support 29 makes it possible to place and maintain a flat iron 33 on the die 24 in a position desired for carrying out a folding operation. The base 30 of the support 29 is placed on the rail 28 at a determined distance from the support 25 of the matrix 24 and the holding device 32 is adjusted in height so that the flat iron 33 comes to rest, in a horizontal arrangement, on the upper part of the die 24. The end of the flat iron 33 abuts the support flange 35 of the support and is held laterally by means of the holding device 36.

The support 29 ′ allows, in the same way, the establishment on the matrix 24, in the desired position for carrying out a folding operation, of a part 33 ′ on which certain folding operations have been carried out previously.

The supports 29 and 29 ′ are adjusted and placed on the table 26 so as to maintain the parts 33 and 33 ′, temporarily, during the approach movement of the matrix 24 constituting the mobile tool of the press, until the end edge of the active part of the punch 23 comes into pressure contact with the upper surface of the parts 33 and 33 ′.

The motor means for moving the matrix 24 and its support 25 constituted for example by hydraulic jacks can be controlled by a manual device 39 of known type produced in the form of a double electrical contactor comprising two actuating rods 40 and 40 ′ ended with poi gnées which must be actuated simultaneously in the direction of arrows 41 and 41 ′ respectively, to ensure the implementation of the drive means.

To ensure this control of the motor means, the operator must therefore use his two hands which are, at the time of the press control, in a zone remote from the working zone of the tools 23 and 24, the control means 39 being placed largely outside the press work area. In addition, the maintenance and positioning of the parts on which the folding is carried out are provided by the supports 29 and 29 ′, without manual intervention by an operator.

When the control 39 of the motor means for moving the matrix 24 and its support 25 is actuated, the assembly constituted by the matrix 24, the support 25, the table 26, the supports 29 and 29 ′ and the parts 33 and 33 ′ moves upwards in the direction of arrow 43, to pass, firstly, from the open position of the press shown in FIG. 4 to a position in which the end edge of the active part of the punch 33 has come into contact with the upper face of the parts 33 and 33 ′.

This first phase is a phase of approach to press tools.

The pressure which is maintained in the displacement cylinders of the die 24 then makes it possible to fold the parts 33 and 33 ′ along the fold line and at the desired angle.

At the end of the folding operation, as shown in FIG. 5, the parts 33 and 33 ′ are inclined upwards and are no longer supported on the corresponding holding devices 32 and 32 ′. The (parts 33 and 33 ′ can indeed move freely upwards, these parts simply resting by their end on the support flange 35 of the holding device 32 or 32 ′ corresponding.

The supports 29 and 29 ′ therefore only ensure the positioning and provisional maintenance of the parts on which the folding is carried out, until the end of the approach movement.

The folding press according to the invention therefore makes it possible, thanks to very simple means, to avoid any risk of accident for the operator who is obliged to carry out the control of the folding operation from a location remote from the area working using both hands and who no longer has to ensure manual maintenance of the parts on which the folding is carried out.

In addition, the operator's work is greatly facilitated, in particular in the case of repetitive operations, since the adjustments preceding a folding operation can be carried out all at once and in a simpler and faster manner thanks to to supports such as 29 and 29 ′ carried by the table 26.

In addition, it is possible to place one after the other several supports such as supports 29 or 29 ′ carried by a guide means such as 28 or 28 ′. In this case, several pieces can be put in place simultaneously, on which simultaneous bending operations will be carried out during a single press operating cycle. This increases the productivity of the folding press.

In general, work on the press according to the invention is less tiring and less painful for the operator than on a conventional folding press according to the prior art.

It is obvious that the invention is not limited to the embodiment which has been described.

This is how one can imagine the use of supports for holding the parts on which the folding is carried out, of a shape different from that which has been described. These support devices include holding means adapted to the shape of the parts on which the folding operations are carried out.

It is possible to use a number of supports greater than two allowing simultaneous folding of more than two pieces.

One can imagine any means for adjusting the position of the supports on their rails and the height adjustment of the parts holding means.

It is obvious that the invention would apply in the case of a part comprising a movable upper tool and a fixed lower tool.

In this case, the supports of the parts would be mounted on a table secured to the fixed lower tool.

The invention applies to any folding or bending machine and more generally to any metalworking machine in the form of flat parts comprising at least one tool movable in a vertical plane in order to bring it closer or away from a tool complementary, the work of the part being carried out between these two tools. The invention applies, for example, to a punching machine having a fixed part and a movable part between which the punching of a flat part is carried out.

Claims (7)

1.- Metalworking machine for flat parts with improved security comprising a vertical frame (20), an upper tool (23) and a lower tool 5 (24) with relative displacement in the vertical direction, arranged one above on the other on the frame (20), at least one of which is associated with a displacement motor means making it possible to bring it closer or away from the second tool by displacement in a vertical plane, to carry out the work of the piece (33, 33 ′) between the tools (23, 24) or its release, respectively, and a control means (39) of the motor means, characterized in that it further comprises a horizontal table (26) integral of the lower tool (24), at least one guide means (28, 28 ′) fixed on the upper face of the table (26) in a direction substantially perpendicular to the plane in which the mobile tool (24) moves and at least one support (29, 29 ′) mounted adjustable on the guide means and comprising ant a holding part (32, 32 ′) of the part (33, 33 ′) adjustable in height on the support (29) and that the control means (39) of the motor device is constituted by a double electrical contactor comprising two elements (40, 40 ′) the simultaneous manual actuation of which is necessary to ensure that the motor device operates, in the direction of bringing the tools (23, 24) closer. 2.- Machine according to claim 1, characterized in that the support (29, 29 ′) comprises a base (30) slidably mounted on the corresponding guide means (28, 28 ′) and at least two columns (31) for adjusting the height of a holding device (32, 32 ′) of a part (33, 33 ′). 3.- Machine according to claim 2, characterized in that the holding device (32, 32 ′) comprises a support (34) having a flange ap pui (35) for the part (33, 33 ′) and a device (36) for lateral support of the part (33, 33 ′) which is free to move upwards, relative to the holding device (32, 32 ′). 4.- Machine according to any one of claims 1, 2 and 3, characterized in that it comprises at least two guide means (28, 28 ′) carried by the table (26) and parallel to one the other and at least two supports (29, 29 ′) each slidably mounted on a guide device (28, 28 ′), the supports (29, 29 ′) allowing the maintenance of at least two parts (33, 33 ′), For their simultaneous work by the machine. 5.- Machine according to any one of claims 1 to 4, characterized in that the lower tool (24) is movably mounted on the frame (20) and associated with the motor means. 6.- Machine according to claim 5, characterized in that the lower tool (24) is mounted on a flat support (25) on which is fixed the table (26). 7.- Machine according to claim 6, characterized in that the lower tool (24) consists of a die having on its upper surface a V-shaped groove.

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