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The present invention relates to the field of presses for hot forging metal components, typically made of brass.

These presses usually have a vertically movable slide, which carries one half of a die adapted to close against a lower portion carrying the other half of the die, so as to externally shape the metal component.

The press also has movable punches which can be inserted within the die transversally to the closing direction of the die and are capable of deforming the piece, typically in such a way as to form cavities in the same component.

The press is normally provided with multiple levers that transform the vertical descent movement of the movable slide into a horizontal movement transmitted to carriages that can be translated, which are typically movable orthogonally with respect to the movable slide, and carry the punches that penetrate the die.

In particular, eccentric mechanical presses are known with a connecting rod that actuates the slide which impacts against the lower die (containing the other half of the shape to be made) during the descent step. The lower die is generally fastened to a movable body sliding vertically on guides and is held suspended by a large hydraulic or pneumatic cylinder that must guarantee the closing force between the upper die and the lower die.

The descent movement of the slide mechanically actuates the aforesaid punches which simultaneously penetrate the dies with a typically horizontal movement.

In addition to the total stress required to penetrate the punches and overcome the friction of the idler levers, this solution also requires a significant force to overcome the counterthrust of the cylinder for supporting the movable body with the lower die. Furthermore, the impact between the die portions also generates a high level of acoustic noise and high strain on the press elements.

Additionally, during the penetration step of the punches into the dies, due to the possible different punch dimensions, different forces are generated at the thrust points of the idler levers and, despite the guides, the movable body can tilt and the moulded piece is sometimes defective. Oleodynamic presses are also known, in which the vertical movement of the slide is achieved by means of one or more oleodynamic cylinders. The upper die is fastened to the lower plane of the moving slide, while the lower die is fastened to the body of the equipment, which in turn is stably mounted on a base plate. The equipment with the lower die fastened to the base plate has toggle-joint levers that actuate the orthogonal punches. Toggle lever systems provide that the levers are oriented downwards and actuated by hydraulic cylinders that start the movement after the dies have been clamped.

The actuation of the cylinders connected to the levers and base is ensured by a high- pressure oleodynamic system with independent circuit and nitrogen storage. Since the nitrogen pre-charge pressure in the storage cannot be easily modified, it follows that the charge force for the oil used for the exit and return stroke of each cylinder always remains at maximum, regardless of the type of piece to be deformed. This type of presses further allows to produce a reduced number of pieces per unit of time, which is lower than, e.g., an eccentric continuous-cycle press.

Finally, presses in which the descent and ascent movement of the slide is controlled by an electric motor are known, which cannot generate the closing force of the dies on its own, thus requiring the presence of an additional oleodynamic cylinder.

This type of press also has low productivity.

An object of the present invention is therefore to provide a new press which has a reduced noise level.

A further object of the present invention is to provide a press that can significantly reduce the force required during use and therefore the available and absorbed power. These and other objects are achieved by a press and a respective operating method according to one or more of the accompanying claims.

In particular, object of the present invention is a press and a respective operating method according to the accompanying independent claims. Preferred aspects are set forth in the dependent claims.

Therefore, an aspect of the present invention relates to a press for hot forging typically metal objects and, in particular, brass objects, comprising a main body; a first die portion constrained to the main body; a slide equipped with a second die portion, which is movable in use with respect to the main body along a first direction between a first position of disengagement from the first die portion and a second position of engagement with the first die portion; at least one carriage, which is movable in use with respect to the main body along a second direction substantially orthogonal with respect to the first direction, comprising at least one punch; a slider, which is movable in use with respect to the main body along a third direction, substantially parallel to the first direction and transverse, preferably orthogonal to the second direction; a kinematic mechanism comprising a connecting rod hinged at a first point to the carriage and at a second point to the slider, a crank hinged at the second point to the slider and the connecting rod and at a third point to a supporting element constrained to the main body. The slide comprises an actuating portion and the press is configured so that, in the disengagement position, the actuating portion of the slide is released from the slider and, during the movement of the slide along the first direction between the disengagement position and the engagement position, the actuating portion comes into contact with said slider, so as to cause its movement along the third direction and, as a result, to move the movable carriage along the second direction by means of the kinematic mechanism, by bringing the punch closer to the first and second die portions. The shape of the press allows to modulate the force applied by the punch to the object contained between the die portions and, as a result, to modulate the reaction forces acting on the same press.

According to a possible aspect, the press comprises a first regulation element adapted to control the movement of the slider along the third direction, prior to the contact between said actuating portion and said slider.

This allows to reduce the relative velocity between the carriage and the slide, so as to reduce the noise level of the press, as well as the impact forces acting thereon. It should be noted how the press is typically equipped with a plurality of carriages. The carriages are essentially similar to each other, except for the possible different dimensions of the respective punch. However, it is possible to regulate the movement, i.e. the law of motion, of the various punches independently one from the other, in particular by operating regulation elements differently one from the other, combined with different carriage sliders. According to a possible aspect, the first regulation element comprises an electric motor or a hydraulic component.

According to a possible aspect, the first regulation element is configured so as to stop its slider movement action upon contact between slider and actuating portion.

Thanks to this, the movement of the punches is exclusively mechanical, i.e. controlled only by the mechanical coupling between slide, slider and punch-holder carriage.

In particular, according to a possible aspect, the first regulation element is operated in such a way that the relative velocity between slide and slider, at the moment of the contact between them, can be lower than the relative velocity between slide and main body.

According to a possible aspect, in the condition of use, in the disengagement position between slider and actuating portion, the second point is arranged above the first point and the third point.

The configuration of the connecting rod and crank thus forms a toggle with the “knee” arranged above the “leg” portions (i.e. the connecting rod and the crank) of the toggle in an idle condition; the “knee” is then moved by the action of the slide on the slider in a direction substantially coincident with the first direction.

The present configuration also allows a particularly fast press movement and a high productivity.

This allows an effective distribution over time of the force of the punches on the object placed between the die portions.

According to a possible aspect, the press comprises a second regulation element, preferably but not necessarily equipped with an electric motor, adapted to move the supporting element with respect to the main body, preferably along a direction substantially coinciding with, or parallel to, the second direction.

This allows to fine-tune the position of the toggle formed by the connecting rod and crank, so as to regulate the stroke of the punch, its velocity and the force it exerts on the object placed between the die portions of the press. The second regulation elements combined with different carriages can also act differently from each other on the respective supporting elements.

It should be noted how different carriages can be controlled differently from each other, i.e. disjointedly from each other; in other words, during use, it is possible that the first and/or second regulation element acts on the respective slider in a different manner than the operation of a corresponding regulation element connected to a different slider.

According to a possible aspect, the slide comprises a main portion and the actuating portion can be translated with respect to the main portion; in particular, the slide comprises a third regulation element adapted to move the actuating portion with respect to the main portion, preferably along a direction parallel to or coinciding with the first direction, in the direction opposite to which the main portion is moved.

This allows the relative velocity between actuating portion and slider to be further reduced.

It should be noted that, in general, a slide equipped with a main portion and a actuating portion movable with respect to the main portion and configured to control the movement of the punches, can also be used with a configuration of the kinematic mechanism adapted to move the punches, i.e. with a configuration of the lower portion of the press which is different from what is shown. In general, the upper portion of the press described herein, i.e. comprising a slide with a respective actuating portion movable with respect to the slide as described below, can generally be used to move punches arranged below, by means of a special kinematic connection between punches and actuating portion of the slide, i.e. between the carriages carrying the punches and the actuating portion of the slide.

According to a possible aspect, the third actuating element comprises a motor element and a rocker lever having fulcrum on the main body or on an element constrained thereto: the motor element and the actuating element are constrained to a rocker lever, distally to each other with respect to the fulcrum.

The present invention further relates to a method for hot forging an object by means of a press according to one or more of the aspects discussed above, comprising the steps of: i. Inserting an object to be deformed into the first die portion; ii. Preferably, controlling the movement of the supporting element by means of the second regulation element; iii. Moving the slide toward the first die portion; iv. Preferably, controlling the movement of the slider and/or the actuating portion by means of the first regulation element and/or the third regulation element, so as to reduce the relative velocity between slider and actuating portion; v. Contacting the slider with the actuating portion; vi. Continuing the movement of the slide toward the first die portion so that the contact between slider and actuating portion causes the insertion of the punches between the die portions (3a, 3b) so as to deform the object contained therein.

With reference to the accompanying figures, exemplary and non-limiting embodiments of the present invention are now discussed, wherein:

- Figure 1 is a side view of a press according to an embodiment of the present invention;

- Figure 2 is a view of the lower portion of the press of figure 1;

- Figure 3 is an enlarged view of a detail of figure 3;

- Figure 4 is a view of the upper portion of the press of figure 1;

- Figure 5 is an enlarged view of a detail of figure 4;

- Figure 6 is an enlarged view of a further detail of figure 4.

A press 1 for hot forging metal objects comprises a main body 2 and a first die portion 3a constrained to the main body 2.

The press 1 further comprises a slide 4 equipped with a second die portion 3b. The slide 4 is movable so that the second die portion 3b is movable along a first direction DI between a first position of disengagement from the first die portion 3a and a second position of engagement with the first die portion 3a.

The press 1 further comprises at least one carriage 5, which is movable in use with respect to the main body 2 along a second direction D2 transverse to, preferably substantially orthogonal to, the first direction DI.

Typically, the press comprises a plurality of carriages 5 substantially shaped in a similar manner; for the sake of simplicity, a single carriage 5 is therefore described below. Unless explicitly specified, the characteristics of the carriage 5 described below apply to all carriages 5 of the press 1.

With reference also to figure 2, carriage 5 comprises a punch 5a, only partially shown in the figures, adapted to be inserted between the die portions 3 a, 3b so as to deform, in use, an object contained between the die portions 3a, 3b. Punches 5a of different carriages can have different shapes and, in particular, different dimensions. Each carriage is constrained to a slider 6. In particular, the slider 6 is configured so as to be movable, in use, along a third direction D3 substantially perpendicular to the second direction D2.

The carriage 5 is constrained to the slider 6 by means of a kinematic mechanism which comprises a connecting rod 7 hinged at a first point Pl to the carriage and at a second point to the slider 6, a crank 8 hinged at the second point P2 to the slider 6 and to the connecting rod 7, and at a third point P3 to a supporting element 9 constrained to the main body 2.

In a known manner, therefore, the motion along the D3 direction (typically vertical in use condition) of the slider 3 is transformed by the connecting rod 7 - crank 8 system into a motion of carriage 5 along the D2 direction (typically horizontal in use condition).

The point P2 is typically arranged on an element 10 which is integrally translated along the third direction D3 with the slider 6. Typically, however, the element 10 is movable with one degree of freedom with respect to the slider 6, typically it is movable with respect thereto perpendicularly to the third direction D3, i.e. typically substantially parallel to the second direction D2. Therefore, the second point P2 is integrally translated with the slider 6 along the third direction D3 and, due to the kinematic connection between connecting rod 7 and crank 8, has a (typically reduced) mobility also along the second direction D2.

The supporting element 9 can be integral with the main body 2 (possibly made in one piece therewith) or can be translatable with respect thereto, such as in the embodiment shown in the figures, typically along the second direction D2.

The press 1 is preferably configured in such a way that, considering the use condition, in the first position of disengagement between the die portions 3a, 3b, the second point P2 is arranged above the first point Pl and the third point P3.

The slide 4, a possible embodiment of which is described below, is equipped with an actuating portion 4a adapted to cooperate with the slider 6 so as to move the slider 6 and, as a result, by means of the kinematic mechanism composed of the connecting rod 7 and the crank 8, the carriage 5 which carries the respective punch 5a.

This actuating portion 4a is disengaged from the slider 6 in the disengagement position between the die portions 3a, 3b. When the slide 4 is moved toward the first die portion 3a, during its path, the actuating portion 4a comes into contact with the slider 6.

The contact between the slide 4, which moves along the first direction DI, and the slider 6 forces the latter to move along the third direction D3 and, as a result, moves carriage 5 toward the die portions 3a, 3b.

The actuation of the carriage 5 is therefore mechanical, i.e. it is caused by the movement of the slide 4 and by the kinematic connections that are made between the slide 4 and the carriage 5.

However, the carriage 5 preferably comprises a first regulation element 11 adapted to move the slider 6 along the third direction, prior to the contact between the same and the actuating portion 4a of the slide 4.

In other words, the regulation element 11 does not act on the slider 6 when the punches 5a are deforming the object placed between the die portions 3a, 3b, or in any case after the contact between the slide 4 and the slider 6.

The regulation element 11 is typically configured so that, prior to the contact between slide 4 (more precisely, actuating portion 4a) and slider 6, the slider 6 is controlled in its movement by the regulation element along the third direction D3. Thanks to this, at the moment of contact, the relative velocity between slide 4 and slider 6 is lower than the relative velocity between slide 4 and main body 2.

Preferably, the regulation element 11 is configured to move the slider 6 at a velocity close to the velocity at which the slider 4 moves along the first direction DI. Thereby, the relative velocity between the two components at the moment of respective contact is minimal, thus reducing the impact stresses acting on the slider 6 and, consequently, reducing the noise pollution caused by the contact therebetween.

As discussed, following the contact between slide 4 and slider 6, the regulation element 11 no longer controls the movement of the slider 6, which is therefore exclusively controlled by the slide 4.

According to a possible aspect, the regulation element 11 comprises an electric motor I la adapted, e.g., to control a worm screw 11b kinematically connected to the slider 6.

The electric motor I la can be configured so as to draw power from the slider 6, following the contact between slider 6 and slide 2.

An alternative solution to the electric motor provides for the use of a hydraulic component. It should be noted that “hydraulic” means an element configured to operate with a generic liquid, not exclusively water. Typically, this hydraulic element in fact operates with oil.

According to a possible aspect, the press comprises a second regulation element 12 adapted to move the supporting element 9, along a direction substantially parallel to or coinciding with the second direction.

This regulation element 12 typically comprises an electric motor 12a. Such electric motor can control a worm screw 12b adapted to move inclined threaded surfaces 12c. The movement of these inclined surfaces (which typically occurs in an opposite manner to each other), by interacting with respective inclined and threaded surfaces of the supporting element 9, causes a movement thereof.

The regulation element 12 modifies the initial condition of the crank 8 and, typically, also of the connecting rod 7. A movement of the supporting element 9 in fact modifies the position of at least the point P3 and typically also of the point P2 and the point Pl, so as to vary the position of at least the crank 8 with respect to the main body 2 and typically also the relative angle between connecting rod 7 and crank 8.

As previously discussed, the slide 2 can assume different configurations, as long as it is equipped with an actuating portion 4a adapted to cooperate with the slider 6. According to a possible aspect, the slide 4 is movable along the first direction DI. The press 1 typically comprises an actuating device 14 adapted to move the slide 2. This actuating device can vary in different embodiments and can be, e.g., electric or hydraulic (always understood in the general sense of the term and, therefore, e.g. comprising oleodynamic actuators, such as oil jacks).

The law of motion of the slide is preferably non-linear, i.e. neither the acceleration nor the velocity of the slide is constant over time.

In preferred solutions, such as the one shown in the figures, the actuating device is an eccentric electrical device.

According to a possible solution, an electric motor (not shown in detail) controls a first gear 14a, on the axis of which a flywheel is typically fastened, which meshes with a second gear 14b having larger dimensions (i.e. larger diameter) than the first gear. The second gear 14b in turn meshes with a third gear not shown in detail in the figures, typically having smaller dimensions than the second gear 14b. This third gear in turn meshes with a fourth gear 14c having larger dimensions than the third gear 14. A connecting rod-crank system 14d is eccentrically connected to the third gear 14c. The connecting rod-crank system controls the movement of the slide 4.

Preferably, the slide 4 comprises a main portion 4b and the actuating portion is translatable with respect to the main portion 4b, typically at least along the direction D2. The main portion 4b is typically directly connected to the actuating device 14, e.g. to the connecting rod-crank system 14d.

The press 1, therefore, preferably comprises a third regulation element 13 adapted to move the actuating portion 4a with respect to the main portion 4b.

It should be noted that the definitions “first”, “second” and “third” regulation elements are chosen for convenience of description only. Therefore, the second regulation element can be used without the first regulation element, as well as the third regulation element could be used in a press without first and/or second regulation element.

Preferably, the third regulation element 13 comprises a motor element 13a and a rocker lever 13b having fulcrum F on the main body 2 or on an element 13c constrained thereto. The motor element 13a and the actuating portion 4a are constrained to the lever 13b distal to each other with respect to the fulcrum F.

The motor element 13a and the actuating portion 4a are typically hinged to the lever 13b, preferably by means of elements 15 slidingly constrained to the motor element 13a and the actuating portion 4a. In particular, these elements 15 are integrally translated along the first direction DI with the motor element 13a and the actuating portion 4a, respectively, but are translatable along the second direction D2 (or in any case a direction parallel thereto) with respect thereto.

The motor element 13a can be configured in various ways, it can be e.g. electric or hydraulic (in the broad sense of the term described above). A preferred solution provides for an electric control, by means of an electric motor controlling a worm screw.

According to a preferred aspect, the third regulation element 13 is configured so as to reduce the velocity of the actuating portion 4a along the first movement direction DI. In particular, the third regulation element 3 is preferably configured so that during the travel of the slide 4 along the first movement direction DI, the actuating portion 4a is moved in turn along the first movement direction DI (or in any case a direction parallel thereto) but in the opposite direction with respect to the slide, so that the overall velocity of the actuating portion 4a is lower than that of the main portion 4 of the slide. This helps to reduce the relative velocity between actuating portion 4a and slider 6 as much as possible, so as to further reduce the stress and noise of the press 1.

In particular, according to a preferred aspect, the third regulation element 13 acts on one end of the lever 13b, causing it to rotate around the fulcrum F. This rotation causes a movement of the actuating portion 4a.

The fulcrum F is preferably arranged in such a way as to define an axis of rotation for the lever 13b, which is arranged substantially perpendicular to both the first direction DI and the second direction D2.

The fulcrum F can be arranged directly on the main body 2 of the press 1 or on a regulation element 16 constrained to the main body 2, preferably with at least one degree of freedom with respect thereto.

It should be noted how typically the press 1 comprises a plurality of third regulation elements 13. According to a preferred aspect, the various third regulation elements 13 are synchronised with each other. According to a possible solution visible e.g. in the detail of figure 6, the various third regulation elements are indirectly constrained to each other by means of a central gear 13d. In particular, the motor element 13a of each third regulation element is constrained to a respective border gear 13e. The movement of the motor element 13a therefore causes the movement (generally rotationally) of the border gear 13e. The central gear 13d is constrained to all the border gears 13e, so that the movement of the various boreder gears 13e is synchronous. It should be noted how the central gear 13d is single, while there is a border gear 13e for each third regulation element 13.

In general, according to a preferred embodiment, each third regulation element 13 comprises a border gear 13e. The various border gears 13e are constrained to the same central gear 13d used to synchronise the border gears 13e with each other and, consequently, the movement of the various third regulation elements 13.

In use, the slide 4 is moved along the first direction DI so that the actuating portion 4a moves closer to the slider 6. Preferably, during the movement of the slide 4, the first regulation element 11 is actuated so as to move the slider 6 at a velocity close to that of the slide 4. A further regulation can be made by actuating the third regulation element 13 so as to minimise the relative velocity between actuating portion 4a and slider 6.

Generally, the second regulation element 12, if present, is possibly actuated prior to the actuation of slide 4, so as to fine-tune the initial position of the third point P3. Once the actuating portion 4a has come into contact with the slider 6, the descent of the slide 4 moves, by means of the connecting rod 7, the carriage 5 and, as a result, the punch 5a. In particular, the two die portions 3 a, 3b come into contact with each other and the punches 5a are inserted therebetween, so as to deform an object contained therein. The shape of connecting rod 7 and crank 8, forming a toggle, allows to modulate the force applied by the punch on the object placed between the die portions 3a, 3b, typically increasing over time.