Stamping press and method for stamping a round blank
A stamping press for stamping a round blank. A ram movable in a stroke direction and in an opposite return stroke direction carries a first stamping tool. A second stamping tool and a stamping ring are supported on a press framework. The stamping tools and a stamping opening formed by the stamping ring are aligned along a working axis. An ejector device serves to eject a stamped round blank from the ring opening. It comprises an ejector pin supported on an actuating device that is movably coupled with the ram. During a return stroke of the ram the ejector pin can apply a force on the second stamping tool in order to press the round blank out of the stamping ring. In a ram movement in the stroke direction the actuating device departs from the second stamping tool and no ejector pin force is applied on the second stamping tool.
1. Stamping press ( 10 ) for stamping a round blank ( 14 ) comprising:
a ram ( 11 ) that is movable in a stroke direction (H) to a stamping position (P) for stamping the round blank ( 14 ) and opposite to the stroke direction (H) in a return stroke direction (R) by means of a rain drive ( 12 );
a first stamping tool ( 13 ) that is arranged at the rain ( 11 ), having a second stamping tool ( 15 ) that is arranged at a press framework ( 16 ) and having a stamping ring ( 22 );
an ejector device ( 30 ) that comprises an ejector pin ( 31 ) that is configured to move the second stamping tool ( 15 ) in the return stroke direction (R) out of the stamping position (P) in an ejecting position (E) in order to eject a stamped round blank ( 14 ) out of the stamping ring ( 22 ), the rain ( 11 ) and the ejector pin ( 31 ) linearly moveable in operative arrangement along a common working axis (A);
a connection device ( 33 ) comprising an actuating device ( 32 ) supporting the ejector pin ( 31 ) and at least one connection rod ( 34 ) that movably couples the rain ( 11 ) and the actuating device ( 32 ) with each other;
a coupling device ( 55 ) is arranged between the actuating device ( 32 ) and the ejector pin ( 31 ) that is configured to couple the actuating device ( 32 ) and the ejector pin ( 31 ) in a coupling position (K) in the return stroke direction (R) with each other and to decouple the actuating device ( 32 ) and the ejector pin ( 31 ) in a decoupling position (D) in the return stroke direction (R) from each other;
the coupling device ( 55 ) comprises a first coupling part ( 56 ) coupled with the actuating device ( 32 ), a second coupling part ( 57 ) coupled with the ejector pin ( 31 ), the first coupling part ( 56 ) and the second coupling part ( 57 ) in the coupling position (K) coaxially arranged along the common working axis (A) positioned in direct contacting relationship with each other, the first coupling part ( 56 ) and the second coupling part ( 57 ) in the decoupling position (D) positioned in non-contacting relationship with each other, and a coupling drive ( 58 ) configured to at least move from the coupling position (K) one of the first coupling part ( 56 ) and the second coupling part ( 57 ) orthogonally or obliquely relative to the common working axis (A) to the decoupling position (D);
wherein in the decoupling position (D) any movement of the actuating device ( 32 ) in the return stroke direction (R) does not cause a movement of the ejector pin ( 31 ) in the return stroke direction (R); and,
wherein the ejector pin ( 31 ) does not engage the second stamping tool ( 15 ) with a force in the return stroke direction (R) until the second stamping tool ( 15 ) has reached the stamping position (P) and the coupling drive ( 58 ) at least moves one of the first coupling part ( 56 ) and the second coupling part ( 57 ) from the decoupling position (D) to the coupling position (K) and the rain ( 11 ) is moved in the return stroke direction (R) by means of the rain drive ( 12 ) after the round blank ( 14 ) has been stamped.
2. Stamping press according to claim 1 , characterized in that the actuating device ( 32 ) comprises a lever arrangement ( 80 ) comprising a first lever ( 81 ) and a second lever ( 82 ) that are connected with each other at a hinge location ( 83 ) in a hinged manner.
3. Stamping press according to claim 2 , characterized in that the ejector pin ( 31 ) is coupled with the first lever ( 81 ) at a first coupling location ( 86 ) that comprises a distance (s 3 ) to the hinge location ( 83 ) in a transverse direction (Q) orthogonal to the stroke direction (H) and to the return stroke direction (R).
4. Stamping press according to claim 2 , characterized in that the connection rod ( 34 ) is coupled with the second lever ( 82 ) at a second coupling location ( 87 ) that has a distance (s 4 ) to the hinge location ( 83 ) in a transverse direction (Q) orthogonal to the stroke direction (H) and to the return stroke direction (R).
5. Stamping press according to claim 4 , characterized in that the ejector pin ( 31 ) is coupled with the first lever ( 81 ) at a first coupling location ( 86 ) that comprises a distance (s 3 ) to the hinge location ( 83 ) in a transverse direction (Q) orthogonal to the stroke direction (H) and to the return stroke direction (R), the distance (s 3 ) between the first coupling location ( 86 ) and the hinge location ( 83 ) is equal to the distance (s 4 ) between the second coupling location ( 87 ) and the hinge location ( 83 ).
6. Stamping press according to claim 1 , characterized in that the second stamping tool ( 15 ) is in contact with a stop ( 19 ) of the press framework ( 16 ) in stroke direction (H), if in the stamping position (P).
7. Stamping press according to claim 1 , characterized in that the second stamping tool ( 15 ) is urged in the stamping position (P) by means of a biasing device ( 18 ).
8. Stamping press according to claim 1 , characterized in that an overload safety device ( 48 ) is arranged at the actuating device ( 32 ) that limits a force that can be transmitted between the actuating device ( 32 ) and the ejector pin ( 31 ).
9. Stamping press according to claim 8 , characterized in that the overload safety device ( 48 ) comprises a fluid chamber ( 41 ).
10. Stamping press according to claim 9 , characterized in that the fluid chamber ( 41 ) is compressible.
11. Stamping press according to claim 8 , characterized in that the actuating device ( 32 ) comprises a lever arrangement ( 80 ) comprising a first lever ( 81 ) and a second lever ( 82 ) that are connected with each other at a hinge location ( 83 ) in a hinged manner, the overload safety device ( 48 ) is coupled with the second lever ( 82 ).
12. Stamping press according to claim 1 , characterized in that the first coupling part ( 56 ) in the operative position includes at least one projection ( 59 ) facing the second coupling part ( 57 ), the at least one projection ( 59 ) of the first coupling part ( 56 ) in the operative position extending parallel to the common working axis (A), the second coupling part ( 57 ) includes at least one projection ( 59 ) facing the first coupling part ( 56 ), the at least one projection ( 59 ) of the second coupling part ( 57 ) in the operative position extending parallel to the common working axis (A), the at least one projection ( 59 ) of the first coupling part ( 56 ) in the decoupling position (D) is offset transverse to the common working axis (A) in non-contacting non-force transmitting relationship with a respective at least one projection ( 59 ) of the second coupling part ( 57 ), and the at least one projection ( 59 ) of the first coupling part ( 56 ) in the coupling position (K) is aligned in contacting force-transmitting relationship with a respective at least one projection ( 59 ) of the second coupling part ( 57 ) in the stroke direction (H) or return stroke direction (R) wherein a movement of the actuating device ( 32 ) causes a movement of the ejector pin ( 31 ).
13. Stamping press according to claim 1 , characterized in that coupling drive ( 58 ) comprises a linear motor.
14. Method for stamping a round blank ( 14 ) by using a stamping press ( 10 ) according to claim 1 comprising the following steps:
Conveying a round blank ( 14 ) between the first stamping tool ( 13 ) and the second stamping tool ( 15 ),
Moving the rain in the stroke direction (H), whereby due to the movement coupling of the rain ( 11 ) with the ejector pin ( 31 ), also the ejector pin ( 31 ) moves in the stroke direction (H) and allows a movement of the second stamping tool ( 15 ) in the stamping position (P), and moving the round blank ( 14 ) into the stamping ring ( 22 ) by means of the first stamping tool ( 13 ),
Pressing the round blank ( 14 ) against the second stamping tool ( 15 ) only when the second stamping tool ( 15 ) is in the stamping position (P),
Moving of the rain ( 11 ) in the return stroke direction (R) away from the second stamping tool ( 15 ),
Moving of the ejector pin ( 31 ) in the return stroke direction (R), if an ejection of the stamped round blank ( 14 ) from the stamping ring ( 22 ) shall be carried out due to the movement coupling of the ejector pin ( 31 ) with the rain ( 11 ).
15. Method according to claim 14 , characterized in that after ejection of a stamped round blank ( 14 ), another round blank ( 14 ) to be stamped is conveyed between the first stamping tool ( 13 ) and the second stamping tool ( 15 ) and concurrently the stamped round blank ( 14 ) is conveyed out of an area between the first stamping tool ( 13 ) and the second stamping tool ( 15 ).
16. Method according to claim 14 , characterized in that the stroke paths of the rain ( 11 ) and the ejector pin ( 31 ) are equal during a return stroke of rain ( 11 ) in the return stroke direction (R), if a stamped round blank ( 14 ) is ejected from the stamping ring ( 22 ).