The present invention relates to a bending press, and more particularly to the system for clamping bending tools to the top panel of a bending press.
With reference initially to
As can be seen in
The stationary bottom panel 12 has bending dies such as 22 fixed thereon, the right section of a die perpendicular to the plane of the figure being V-shaped. The moving top panel 16 serves to carry bending tools or punches 24. Each punch 24 is fixed to the top panel 16 by being clamped between a stationary or intermediate piece 26 which is releasably fixed to the top panel 16, and a pivoting clamp 28 mounted on the intermediate piece 26. Each clamp 28 can pivot relative to the associated intermediate piece 26 about an axis XX′ common to all of the intermediate pieces and parallel to the long direction of the bending press.
With reference to
Mechanical systems other than the pivoting cam 38 could be used for controlling pivoting of the clamp 28. In general, two major types of clamp control can be provided, either control associated with each clamp mounted on an intermediate piece, or else overall control for all of the clamps on the intermediate pieces mounted on the entire top panel 16.
When the bending operations to be performed with the press need to be modified, it is necessary to begin by replacing the tools or punches that were previously mounted on the top panel with new punches. As a general rule, these changes apply to only a fraction of the tools, and thus to only a fraction of the intermediate pieces and clamps 28 of the top panel. In addition, it will be understood that these tool-changing operations and the adjustments that need to be performed after changing a tool constitute periods during which the bending press is not in use. It is therefore very useful to have bending presses in which these stages, in particular tool-changing stages, can be implemented using a minimum number of operations leading to the machine being out of action for a minimum length of time.
An object of the present invention is to provide a bending press fitted with an assembly for fixing tools to the top panel that enables the operations of removing and replacing tools on the moving top panel of the press to be optimized.
According to the invention, this object is achieved by a bending press comprising:
one of the panels being movable vertically relative to the other;
It will be understood that because a plurality of adjacent clamps are pivoted under the control of the same actuator assembly, it is possible to reduce considerably the time needed for changing tools by suitably associating the clamps controlled by a given actuator assembly. In addition, depending on requirements, it is possible to change the clamps that are controlled by a given actuator assembly.
It should also be emphasized that the invention can be applied to circumstances in which the top panel is the moving panel or in which the bottom panel is the moving panel, with the top panel then being stationary.
In addition, and preferably, the clamps serve to fix the bending punches to the top panel regardless of whether it is a stationary panel or a moving panel. Nevertheless, the clamps with their control system could equally well serve for fixing the bending V-shapes which are fixed to the bottom panel. Under such circumstances, the term “bending tool” should be understood as covering not only the punches, but also the bending V-shape.
Preferably, in the bending press, said bottom panel is stationary and said top panel is vertically movable, the press further comprises N intermediate pieces rigidly fixed to said top panel, each clamp is mounted facing an intermediate piece, and the means for causing the clamps to pivot further comprise:
In a preferred embodiment of the invention for fixing punches, each clamp pivoting mechanism comprises two pivot assemblies mounted respectively at the two ends of the intermediate piece associated with the clamp, each pivot assembly comprising a first lever forming said control portion.
Also preferably, for fixing punches, said link means comprise 2n second levers, each second lever being hinged at a first end to the end of a first lever, and means for interconnecting the second ends of the second levers.
Also preferably, each actuator means comprises at least one actuator whose cylinder is secured to the top panel and having a rod whose end is connected to a link means.
Other characteristics and advantages of the invention appear better on reading the following description of various embodiments of the invention given as non-limiting examples. The description refers to the accompanying drawings, in which:
This figure shows in simplified manner the mechanisms Bi, Ci that are provided at the end of each intermediate piece 26 for causing the clamp to pivot relative to the intermediate piece. The mechanisms of the clamp and intermediate piece assemblies Ai within a given module are interconnected by link means given a respective reference L1, L2, L3, or L4. Each link means L is associated with an actuator assembly which, in the particular embodiment described, is constituted by two actuators Vi, Wi whose rods a are secured to the ends of a given link means Li and whose cylinders b are secured to the top panel 16. Preferably, the two actuators are disposed close to the ends of the link means Li.
It will be understood that by causing the actuators V and W associated with a given module M to act simultaneously, simultaneous pivoting will be obtained of the clamps in the corresponding module.
Naturally, other actuators could be used. Nevertheless, hydraulic actuators are particularly suitable since hydraulic actuators are already used for causing the top panel of the press to move.
Each pair of actuators Vi, Wi associated with a given module Mi is controlled by a single hydraulic control circuit Ki. A central control unit UG enables the various hydraulic control circuits Ki associated with the various modules to be controlled individually.
It will be understood that with such a control system, it is also possible simultaneously to control a plurality of modules, depending on which tools need to be changed.
With reference more particularly to
It will be understood that by simultaneously operating the actuators 50 associated with a given module M, the levers 40 are caused to move and thus also the pivot mechanisms B and C of the clamps 28 of the module between the clamping position shown in
With reference to
The mechanism is constituted by an eccentric 60 fixed to the end 40a of the first lever 40. Pivoting of the eccentric 60 causes a follower 62 to move vertically, guided by a vertical slot 63 formed at the end of the intermediate piece 26. The follower 62 which moves in translation is secured to the first end 64a of each of two resilient arms 64, the second end 64b of each arm being secured to the control end 28b of the clamp, the two arms 64 being at an angle relative to the horizontal. When the lever 40 causes the eccentric 60 to pivot in a first direction, the eccentric causes the follower 62 to move downwards, thereby causing the ends 28b of the clamps to move away from the intermediate piece under drive from the arms 64. The first end 28c of the clamp is thus brought into the clamping position. In contrast, when the eccentric 60 is turned in the opposite direction, the follower 62 rises, tending to move the ends 28b of the clamps towards the intermediate piece, thereby bringing the ends 28c of the clamps towards their positions or removing the tool 24.
The modular nature of the bending press of the invention in terms of changing bending tools makes the machine particularly well adapted to implementing the so-called “step-bend” technique. This technique enables parts to be obtained of substantially cylindrical shape by making successive bends that are short and of angles that are wide open. Certain stages of the step-bend technique require a change of tool. Controlling the clamps in modules is then particularly advantageous since it enables the relevant tool to be changed without any need to loosen the adjacent tool. In other words, each module formed by clamps that are controlled simultaneously can be considered as constituting one of the bending stations needed for implementing the step-bend method.
Number | Date | Country | Kind |
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03 05099 | Apr 2003 | FR | national |
Number | Name | Date | Kind |
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6003360 | Runk et al. | Dec 1999 | A |
6450004 | Edmondson et al. | Sep 2002 | B1 |
6557390 | Runk et al. | May 2003 | B1 |
6564611 | Harrington et al. | May 2003 | B1 |
6606896 | Tarasconi | Aug 2003 | B1 |
Number | Date | Country |
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0305099 | Nov 2003 | FR |
06142767 | May 1994 | JP |
09295053 | Nov 1997 | JP |
Number | Date | Country | |
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20040211237 A1 | Oct 2004 | US |