EP2295165B1

EP2295165B1 - Press for simultaneously rough-pressing and finishing / embossing

Info

Publication number: EP2295165B1
Application number: EP10176583.2A
Authority: EP
Inventors: Domenico Caggioli
Original assignee: Mecolpress SpA
Current assignee: Mecolpress SpA
Priority date: 2009-09-15
Filing date: 2010-09-14
Publication date: 2017-05-03
Anticipated expiration: 2030-09-14
Also published as: IT1395741B1; ITMI20091576A1; EP2295165A1

Description

BACKGROUND OF THE INVENTION

The present invention relates to an apparatus for press forging with simultaneous intermediate forging and finishing/embossing.
In hot pressing metal elements, for example of a steel, aluminium and brass material, it is frequently necessary, for achieving the target piece, to perform a starting forming or roughing operation, with a first operating step, and a following finishing or embossing operation, by a second operating step or stroke of the pressing machine.
To that end screw pressing machines, including adjoining pressing dies, either longitudinally or transversely arranged, or also arranged on the press bottom plate in an offset relationship with respect to the axial pressing force of the press are conventionally used.
At first, the heated material length is arranged on the roughing die, and is shaped or contoured by a first press stroke.
Then, the thus processed workpiece is brought to the finishing die and finished by a second press stroke.
It should be apparent that in such a mode of operation, the press construction is subjected to a very high stress, because of the offset arrangement of the press dies.
Accordingly, for preventing any breakage risk, it is necessary to use a larger power pressing machine.
Moreover, also the pressing machine molds or dies, usually a pair of operating dies, must be made with an enlarged size and strong auxiliary guides for achieving a target-shape final piece. Documents EP 0 919 362 A1 and DE 196 11611 disclose known types of forming presses.

SUMMARY OF THE INVENTION

Accordingly, the aim of the present invention is to provide an apparatus for press forging with simultaneous intermediate forging and finishing/embossing allowing to overcome the above mentioned drawbacks of like prior pressing machines.
Within the scope of the above mentioned aim, a main object of the invention is to provide such an apparatus allowing to fully eliminate anomalous stresses on the pressing machine construction.
Another object of the invention is to provide such an apparatus allowing to use a pressing construction having a pressing capability mating the maximum force required by the workpiece, without oversizing the press.
Another object of the present invention is to provide such an apparatus which, owing to its specifically designed features, is very reliable and safe in operation.
According to one aspect of the present invention, the above mentioned aim and objects, as well as yet other objects, which will become more apparent hereinafter, are achieved by an apparatus having the features et forth in claim 1. The apparatus comprises a bottom plate, to be clamped to a base plate on a press bed, two or more guide columns, a central middle movable plate and a top plate to be clamped to the press ram or slide, between the bottom plate and the middle movable plate being arranged a pair of workpiece finishing or intermediate forging half-molds, comprising a finishing or intermediate forging top half-mold and a finishing or intermediate forging bottom half-mold, between said middle plate and top plate being arranged a said pair of said workpiece intermediate forging or finishing half-molds constituted by a intermediate forging or finishing top half-mold and a intermediate forging bottom half-mold, the locating of said finishing or intermediate forging molds between said middle movable plate and bottom plate being an indifferent one.
In other words, the finishing mold or die may be arranged between the middle movable plate and top plate, whereas the intermediate forging or finishing mold or die may be arranged between the middle movable plate and bottom plate while performing the same operating cycle, but with different locations of the molds or dies.
For the first press stroke, a heated piece length is deposited on the top mold or die with the middle plate bearing on or raised from the fixed bottom mold, after having performed the press stroke and during the raising movement of the press ram being simultaneously actuated a middle plate opening or raising system, with said press ram at the top and the movable mold bearing plate at the top, being driven a workpiece ejecting and raising member thereby taking the workpiece and immediately displacing it into the finishing bottom mold or die, simultaneously in said top mold or die being deposited a further heated piece length, said movable middle plate being fully lowered and being performed a press stroke, thereby providing a intermediate forging of said workpiece in the top mold pair and a simultaneously finishing/ intermediate forging in the bottom mold pair, the press operating cycle being then repeated by sequentially displacing the workpieces from the top mold to the bottom mold.
In the inventive pressing apparatus, the roughing and finishing molds or dies are arranged one above the other, perfectly in axis or aligned with the press pushing or pressing axis, while eliminating any anomalous stress and allowing to use a unoversized press, with a pressing capability mating the maximum pressing force required by the workpiece being pressed.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the present invention will become more apparent from the following detailed disclosure of a preferred, though not exclusive, embodiment of the invention, which is illustrated, by way of an indicative, but not limitative, example in the accompanying drawings, where:

Figure 1 is a side elevation view of the apparatus according to the present invention, which is illustrated in an operating step in which a billet is loaded into the top mold or die and an intermediately forged piece is transferred to the bottom molt or die;
Figure 2 is a view similar to figure 1, but showing the apparatus according to the present invention during its operating step for lowering the middle mold holder on the fixed bottom mold or die;
Figure 3 is a view similar to figure 2, but showing the apparatus according to the present invention during a screw press slide or ram lowering step, with a consequent simultaneous intermediate forging and finishing of the workpiece;
Figure 4 is a front closure view of the press apparatus according to the present invention; and
Figure 5 is a top plan view of the apparatus for press forging with simultaneous intermediate forging and finishing/embossing according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the number references of the above mentioned figures, the apparatus for press forging with simultaneous intermediate forging and finishing/embossing according to the present invention, which has been generally indicated by the reference number 1, comprises a bottom plate 13 to be fixed to a base plate 14 on the basement 15 of the pressing apparatus.
The subject press apparatus further comprises two or more guide columns 10, a movable middle center plate 8 and a top plate 16 to be fixed to the ram or slide 12 of the press.
Said ram or slide 12 comprises a top ejecting device 6 for ejecting the workpiece.
Between the bottom plate 13 and movable middle plate 8 a pair of half-molds for finishing or intermediately forging the workpiece, comprising a top finishing half-mold, or a top intermediate forging half-mold 4 and a bottom finishing or intermediate forging half-mold 5.
The base plate 14 comprises an ejecting device 11 for ejecting the workpiece from the bottom mold or die 5.
Between the middle plate 8 and top plate 16 are arranged a pair of workpiece intermediate forging or finishing half-molds, comprising a top roughing or finishing half-mold 2 and a bottom intermediate forging or finishing half-mold 3.
In this connection it should be pointed out that the locating of said finishing or intermediate forging molds between said middle movable plate and bottom plate is an indifferent one.
The movable middle plate 8 comprises a dedicated ejecting device 9 for ejecting therefrom and raising the pressed workpiece to allow the latter to be taken.
The bottom plate 13 is affixed or clamped on the base plate 14 of the press, the top plate 16 being fixed or clamped to the press ram or slide 12.
The middle plate 8 slides on apparatus column guides 10 and being driven by driving cylinders 7 which may be either pneumatic, hydraulic cylinder or electrically-electronically driven system cylinders.
The movable middle plate 8, with the top finishing half-mold 4 and the bottom intermediate forging half-mold 3 is raised, upon a stroke of the press, to open the bottom molds or dies, so as to take the workpiece therefrom or load said workpiece thereinto.
The depositing and taking operation both of the heated piece length and the intermediately forged or finished piece may carried out either manually or by automatic, electronic, hydraulic or pneumatic systems.
As shown, the roughing mold or die may be arranged above the movable middle plate and the finishing mold may be arranged on the fixed bottom plate.
At the working starting first pressing stroke, the heated length is arranged on the top mold with the middle plate 8 bearing on the fixed bottom mold.
After having performed a press operating stroke, and during the raising of the press ram, the middle plate opening or raising system is simultaneously actuated.
With the press ram located at top position and the movable mold bearing plate in a raised condition, the workpiece ejecting device is so actuated as to allow the piece to be taken and immediately brought to the bottom finishing mold.
Simultaneously, a new heated piece length is engaged in the top mold or die; the movable middle plate is fully lowered to perform a novel press stroke, thereby providing an intermediate forging of the workpiece engaged in the top mold pair while simultaneously providing a finishing operation in the bottom mold pair.
At this time, the operating cycle is repeated, by sequentially displacing or driving the workpieces from the top to the bottom mold.
Since the heated length and intermediately forged workpiece are sequentially pressed by a single press stroke, the required pressing force will be gradually increased to the maximum finishing and embossing force, without any impacts between the press molds which would occur if the finishing operation would be carried out by a further dedicated press stroke.
Thus, owing to the absence of mold impacts, the operating noise, as well as the operating stress will be greatly reduced, with a great advantage on the press and mold or die construction.
In this connection it should be apparent that the workpiece loading, taking and relocating and unloading system usually comprises automatically operated arms, thereby allowing a very quick operating cycle to be performed, to achieve, for each press stroke, a finished workpiece.
The apparatus system comprises moreover suitably designed channel patterns for thermo-adjusting the mold or die temperature, to hold the workpiece temperature constant.
Thus, owing to the disclosed molding or pressing system, it is possible to indifferently use both screw pressing machines and eccentric or mechanic presses in general, driven by any suitable driving means such as electric motors, torque motors, brushless motors and so on, as well as hydraulic pressing machines.
Moreover, the apparatus according to the present invention may operate by an automatic operating cycle to load-unload workpieces by using automatic electronic, hydraulic or pneumatic operating arms.
To increase the production yield, without causing an excessive decrease of the temperature of the workpiece being processed, it is preferable to use two independent operating arms.
The first arm, including a double gripper device, after having taken the heated piece length from the heating oven, will be preset for taking the finished workpiece.
With the mold middle plate in a raised condition, the operating arm will engage and take the workpiece, while simultaneously the second operating arm will engage and remove the intermediately forged piece from the top mold or die.
Then, the two operating arms will be immediately located the first at the top mold and the second at the bottom mold to deposit one the heated length into the top mold and the other intermediately forged piece into the finishing mold.
Then, during an operating stroke of the press, the first arm will unload the finished workpiece and take a new piece length to be reloaded.
During the arm mold entering and exiting movements, said mold or dies will be properly lubricated by lubricating spraying device to be also applied on the operating arms.
It has been found that the invention fully achieves the intended aim and objects.
In fact, the invention has provided an automatic apparatus for press forging with simultaneous intermediate forging and finishing/embossing in which, owing to the fact that the intermediate forging and finishing molds or dies are arranged onto one another in a perfectly axially aligned condition with the press pushing axis, will be practically eliminated any anomalous operating stress, thereby it will be possible to use a pressing machine having just the pressing capability necessary for the maximum pressing force on the workpiece.
In practicing the invention, the used materials, as well as the contingent size and shapes, can be any, according on requirements.

Claims

Apparatus for press forging with simultaneous intermediate forging and finishing/embossing, characterized in that said apparatus comprises a bottom plate (13), to be clamped to a base plate (14) on a press bed (15), two or more guide columns (10), a central middle movable plate (8), a top plate (16) to be clamped to the press ram or slide (12), and two pairs of half-molds, wherein:
- a first pair of half-molds, for intermediate forging, comprises an intermediate forging top half-mold and an intermediate forging bottom half-mold; and a second pair of half-molds, for workpiece finishing, comprises a workpiece finishing top half-mold and a workpiece finishing bottom half-mold;

- one of these pairs is indifferently arranged between the bottom plate (13) and the middle movable plate (8) ; the other of these pairs is indifferently arranged between said middle plate (8) and the top plate (16).
An apparatus, according to claim 1, characterized by further comprising driving cylinders of the type pneumatic, hydraulic or electrically-driven and electronically controlled, to drive and slide said middle plate (8) on said guide columns (10).
An apparatus, according to one or more of the preceding claims, characterized by further comprising a slide (12) including a workpiece top ejector (6), the base plate (14) including an ejector (11) for ejecting the workpiece from the bottom mold (4, 5), the movable middle plate (8) including an ejector device (9) for ejecting and raising a molded workpiece to allow said molded workpiece to be gripped.
An apparatus, according to one or more of the preceding claims, characterized by further comprising a plurality of thermoadjusting channels for holding a workpiece temperature at a constant value.
An apparatus, according to one or more of the preceding claims, characterized in that said press apparatus is a screw press or an eccentric or mechanical press, said press being driven by press driving means including electric motors, torque motors, brushless motors, and by hydraulic driving systems.
An apparatus, according to one or more of the preceding claims, characterized by further comprising electronically controlled hydraulic or pneumatic arms for operating the apparatus with an automatic workpiece load/unload cycle, wherein said arms preferably include two independent arms, a first said arm having a double gripper for gripping, with the middle plate (8) of the mold in a raised condition, said workpiece, said second arm simultaneously gripping an intermediately forged workpiece either from the top (2, 3) or from the bottom (4, 5) mold, said first arm being positioned at said top (2, 3) or bottom (4, 5) mold, said second arm being positioned at the bottom (4, 5) or top (2, 3) mold to deposit a heated length in the top mold template and an intermediately forged workpiece in a finishing mold template, said first arm unloading a finished workpiece and gripping a further length to the reloaded.
A method performed on an apparatus for press forging as set forth in any of the claims 1-6, characterized in that for the first press stroke at the start of a press working operation, a heated billet is deposited on the top (2, 3) or bottom (4, 5) mold with the middle plate (8) bearing on or raised from the fixed bottom mold (4, 5), after having performed the press stroke and during the raising movement of a press ram (12) being simultaneously actuated a middle plate opening or raising system (7, 10), with said press ram (12) at the top and the movable mold bearing plate (8) at the top, being driven a workpiece ejecting and raising member (9) thereby taking the workpiece and immediately displacing it into the finishing bottom or top mold (2, 3, 4, 5), simultaneously in said top or bottom mold (2, 3, 4, 5) being deposited a further heated billet, said movable middle plate (8) being fully lowered and being performed a press stroke, thereby providing an intermediate forging/finishing of said workpiece in the top mold pair (2, 3) and a simultaneously finishing/intermediate forging in the bottom mold pair (4, 5), the press operating cycle being then repeated by sequentially displacing the workpieces from the top mold (2, 3) to the bottom mold (4,
The method, according to claim 7, characterized in that said movable middle plate (8) is raised with the top finishing half-mold (4) and the intermediate forging bottom half-mold (3) after opening the bottom molds (4, 5) to allow the workpiece to be gripped and loaded.
The method, according to claims 7 or 8, characterized in that the heated billet and the intermediately forged or finished workpiece are either manually deposited and gripped or automatically deposited or gripped as controlled by electronic, hydraulic or pneumatic systems.
The method according to any of the claims 7 - 9, characterized in that, during inlet and outlet movements of said arms to/from said molds (2, 3, 4, 5), said molds are lubricated by spray lubricating devices supported by said arms.