DE102020215762B3 - Punch for an injection molding machine, use of the punch in an injection molding machine and injection molding machine - Google Patents

Abstract

The invention relates to a stamp (10) for an injection molding device, comprising a stamp rod (12) with a media channel (14) formed within the stamp rod (12), a stamp head (20) arranged at a distal end (18) of the stamp rod (12) , a chamber (22) connected to the media channel (14) being formed inside the stamp head (20), a circumferential groove (26) being formed on an outer side (24) of the stamp head (20), the chamber (22) and the groove (26) are separated from one another by a partition (28) having at least one opening (30), an elastic ring element (32) arranged in the groove (26), and a pressure element arranged and/or formed in the chamber (22). (34), the pressure element (34) exerting a force (56) on the ring element (32) via an applied pressure, so that this can be displaced at least in sections in a direction perpendicular to the longitudinal direction (16) of the stamp (10).

Description

The invention relates to a stamp for an injection molding device for encapsulating semiconductor components, the stamp having a stamp head with a chamber arranged in the stamp head. A pressure element that can be acted upon by a pressure medium is arranged inside the chamber, the pressure element being in operative connection with an elastic ring element. By applying pressure to the pressure element, the ring element can be displaced at least in sections in a direction perpendicular to the longitudinal direction of the stamp in order to clamp and/or seal against an inner wall of a hollow shaft surrounding the stamp. Furthermore, the invention relates to a use of the stamp according to the invention in an injection molding device and an injection molding device with the stamp according to the invention.

Devices for injection molding are known in principle. In the case of the known devices, it is provided that, in addition to an injection molding tool and a hollow shaft coupled to the injection molding tool, they have a piston and/or stamp that can be hydraulically displaced in the hollow shaft. The piston conveys an injection molding material arranged in the hollow shaft along the hollow shaft into an injection molding tool. In the heated injection molding tool, the preferably solid injection molding material changes into a low-viscosity state in order to enclose and/or envelop the workpiece arranged in the injection molding tool at least in sections. A disadvantage of these known methods is that when the injection molding material is injected into the preheated injection molding tool, the low-viscosity injection molding material can flow around the die head. This can lead to the injection molding material being deposited around the die and thus insufficient material being supplied to the injection molding tool for overmolding the semiconductor component. If the injection material settles around the ram, the ram must be relocated at higher pressure for further cycles. Furthermore, the accumulation of material around the punch can lead to increased abrasive use of the punch in subsequent cycles, causing it to wear out more quickly.

From the U.S. 9,847,237 B2 a device for the production of semiconductor modules is known. It is provided that a semiconductor module is placed in a cavity between two injection molds. An injection molding material is then introduced into the cavity via a displaceable piston.

The publication WO 2016/034 990 A1 describes a modular device for pressure encapsulation.

It is an object of the invention to provide a stamp for an injection molding device which can have an increased service life or reduced wear.

This object is solved by the subject matter of independent patent claims 1, 17 and 18, respectively. Preferred developments are the subject matter of the dependent patent claims, the following description and the drawings, with each feature being able to represent an aspect of the invention both individually and in combination, unless the description explicitly states otherwise.

According to the invention, a stamp for an injection molding device is provided, comprising a stamp rod with a media channel formed inside the stamp rod, a stamp head arranged at a distal end of the stamp rod, a chamber connected to the media channel being formed inside the stamp head and a peripheral chamber on an outside of the stamp head groove is formed, the chamber and the groove being separated from one another by a partition wall having at least one opening, an elastic ring element arranged in the groove, and a pressure element arranged and/or formed in the chamber, the pressure element being stretched when pressure is applied experiences and directly or indirectly exerts a force on the ring element, so that it can be displaced at least in sections in a direction perpendicular to the longitudinal direction of the stamp.

In other words, it is an aspect of the present invention that a punch for an injection molding device is provided. The injection molding device is preferably set up and designed to overmold and/or encapsulate semiconductor components with a plastic material at least in sections, preferably completely. The semiconductor components are preferably used in a transmission control unit of an at least partially electrically driven motor vehicle. The injection molding device can also be referred to as a device for transfer molding or in particular as a transfer molding device.

The stamp includes a stamp rod with a media channel formed within the stamp rod. The plunger rod is preferably formed in a straight line or along a longitudinal axis. The same applies to the media channel within the stamp rod. The plunger rod has a distal end. A punch head is formed at a distal end of the punch rod. A chamber is arranged within the punch head, the chamber being directly or indirectly connected and/or coupled to the media channel. A circumferential groove is formed on an outside of the punch head. A groove depth of the groove is preferably arranged and/or formed in a direction perpendicular to the longitudinal direction of the punch or the punch rod. The chamber formed in the punch head and the circumferential groove are separated from one another by at least one partition. The partition wall is preferably designed to be circumferential. A closed edge opening is formed in the partition. The opening thus establishes a connection between the groove and the chamber. An elastic ring element is provided or arranged in the groove. Furthermore, a pressure element is arranged and/or formed in the chamber, the pressure element being media-tight and/or media-technically connected to the media channel of the punch head, so that when pressure is applied, the pressure element expands and directly or indirectly exerts a force on the ring element. In this case, the pressure element can preferably deviate at least in sections through the opening. The elastic ring element is displaced at least in sections in a direction perpendicular to the longitudinal direction of the stamp by the acting force. The pressure to inflate the pad can be fluid or gas such as air.

By shifting the elastic ring element at least in sections in the direction perpendicular to the longitudinal direction of the ram, it is possible—if the ram is arranged in a hollow shaft of an injection molding device—to seal and/or brace the ring element against an inside of the hollow shaft. Due to the fact that the pressure element can be pressurized on the one hand and the pressure can also be released again, the contact pressure of the elastic ring element on the inside of the hollow shaft can be changed. If the stamp is displaced within the hollow shaft in the longitudinal direction of the hollow shaft, the abrasiveness of the stamp can thus be reduced, so that the longevity of the stamp or its service life is increased.

The pressure element can be designed as an elastic cushion and/or have a cushion-like configuration, with at least one opening for filling the cushion with the pressure medium being provided in the cushion.

However, it is also conceivable that the pressure element is an elastic membrane or an elastic foil, which is preferably arranged in a materially bonded manner on an inner side of the partition wall, which is formed on a side facing the longitudinal axis of the stamp or stamp head. The pressure element can be designed in one piece or particularly preferably in multiple parts. In the case of a multi-part design, it can be provided that the pressure element is formed from the elastic membrane or film, preferably in the form of a circular ring, with a force transmission element being arranged at least in sections in the opening of the partition wall, which transmits a force applied via the membrane or film to the elastic ring element transmits. The elastic ring element and/or the elastic pressure element are preferably formed from an elastomer and/or a silicone. The elastomer is preferably a rubber, in particular formed from a synthetically produced rubber. The elastic ring element and/or the elastic pressure element are particularly preferably made of perfluoro rubber (FFKM) or fluoro rubber (FKM). Perfluoro rubber has increased chemical and increased temperature resistance, which is particularly advantageous in an injection molding device. It is conceivable that the elastic pressure element, preferably the elastic membrane or film, is made from a silicone, in particular a two-component silicone “2K silicone”. The power transmission element is preferably made of a rubber, for example a rubber as described above. It is conceivable that the rubber of the elastic ring element is the same as the rubber of the force transmission element. It is advantageously provided that the rubber of the force transmission element is different from the elastic ring element and/or has different material properties compared to the elastic ring element. Particularly preferably, the force transmission element has a higher strength and/or hardness than the elastic ring element.

In principle, the media channel within the plunger rod can be designed in such a way that a pressure medium, preferably a gaseous pressure medium or a fluid pressure medium, can be supplied to the stamp head. In an advantageous development of the invention, it is provided that the media channel is designed coaxially to the longitudinal axis of the plunger rod. The plunger rod can thus preferably be designed in the form of a hollow cylinder. Such a stamp rod can be produced inexpensively.

In an advantageous development of the invention, it is provided that the stamping head is materially bonded, form-fitting and/or force-fitting located on the distal end of the plunger rod. A material connection can preferably be an adhesive connection and/or a welded connection. However, it is particularly preferably provided that the connection between the ram head and the ram rod is a form-fitting and/or force-fitting connection. There should preferably be a screw connection underneath. If the punch head is worn, it can easily be detached from the punch rod and replaced via a screw connection. In this way, in particular, the operating costs of the stamp or the injection molding device can be reduced, since wearing parts can be replaced in a simple manner.

In a preferred development of the invention, it is provided that the punch head is aligned coaxially to a longitudinal axis of the punch rod via and/or with the aid of a first centering device. In this way, a high degree of precision for arranging the stamp head on the stamp rod can be made possible. The first centering device can preferably have a circumferential fold that is formed on a face of the distal end that faces the punch head. For this purpose, the punch head has a corresponding material recess in the form of a counter fold on a front face that faces the distal end, so that the fold of the distal end can engage in the counter fold. In this way, a high degree of centering accuracy between the punch head and the punch rod can be made possible.

A preferred development of the invention provides that the ram rod and the ram head are each cylindrical, the ram head is arranged coaxially with the ram rod, and an outer diameter of the ram head is larger than an outer diameter of the ram rod.

It is conceivable that the punch head is designed in one piece. This has the advantage that the punch head as such consists of few components, can be produced inexpensively, has increased tolerance accuracy, and is easily exchangeable as a one-piece structure, since only one connection to the punch rod has to be released if the punch head should be worn. In this context, one-piece means that the entire punch head is made of one material or is milled from one block. It is also conceivable that the punch head is cast or is produced in one piece by means of an additive process.

As an alternative to the one-piece design of the stamp head, an advantageous further development of the invention is that the stamp head is designed in multiple parts and has at least one connecting part and one sealing part, with the connecting part being arranged between the sealing part and the stamp rod, and at least the sealing part having the circumferential groove and /or the Chamber trains. Due to the multi-part design of the stamp head, the pressure element can be inserted into the chamber of the sealing part in a simple manner. In this way, the entire punch head can be assembled easily.

In this context, it is advantageously provided that the connecting part delimits the chamber on a side of the chamber facing the plunger rod. In other words, it is initially provided that the pressure element is inserted into the chamber of the sealing part either as a cushion or as a membrane on the inside of the partition wall in a materially bonded manner. The connecting part is then placed on the sealing part, so that the connecting part delimits the chamber at least on one side. The pressure element is consequently arranged in the chamber and, in relation to the longitudinal direction of the ram, cannot escape from the chamber.

In an advantageous development of the invention, it is provided that the connecting part and the sealing part are connected to one another in a form-fitting, force-fitting and/or cohesive manner. An integral connection is preferably an adhesive connection and/or a welded connection. Provision is particularly preferably made for the connecting part and the sealing part to be screwed together, by which is meant a non-positive and/or positive connection. The screw connection is simple and inexpensive to produce. In addition, in this way the sealing part can be connected to the connecting part in a simple manner after the insertion or the arrangement of the pressure element in the chamber.

According to a preferred development of the invention, it is provided that the connecting part and the sealing part are centered on one another via a second centering device. The second centering device can be designed in the form of a fold. For this purpose, a peripheral fold is preferably formed on an end face of the connecting part formed on the sealing part. Corresponding to this circumferential fold, a circumferential projection or a counter fold is formed on an end face of the sealing part, which faces the connecting part. The projection engages in the circumferential fold and in this way centers the connecting part and the sealing part in relation to one another.

The pressure element is designed and arranged in the chamber in such a way that a pressure medium, be it gaseous or a fluid, enters the pressure element if it is designed as a cushion, or enters the chamber and acts against the membrane. An advantageous development of the invention is that the pressure element is designed as a cushion and has a socket that protrudes at least in sections into the media channel of the plunger rod and/or an extension of the media channel in the plunger head and/or the connecting part. In this way, the pressure element designed as a cushion can be centered in the chamber via the socket. The socket can preferably only be inserted into the media channel. However, it is also conceivable that the connecting piece is screwed into and/or arranged in the media channel or the extension of the media channel within the connecting part.

In a preferred development of the invention, it is provided that the pressure element has a circular configuration in a cross section perpendicular to the longitudinal direction of the stamp. In this way, the pressure element can preferably build up a uniform pressure in its radial direction and experience a uniform expansion in its circumferential direction in order to move the elastic ring that is operatively connected to the pressure element at least in sections in the radial direction or in the direction perpendicular to the longitudinal direction of the punch to relocate outside.

An advantageous development of the invention lies in the fact that the elastic pressure element is designed as a circular elastic membrane or elastic film which rests against the inside of the partition wall and/or seals with it. The membrane or the film is preferably arranged on the inside of the partition in a material-to-material and/or form-fitting manner. The material connection can preferably be an adhesive connection. It is conceivable that the elastic membrane or film is and/or is cast onto the inside of the partition wall. For this purpose, it can advantageously be provided that the chamber is at least partially encapsulated with the silicone. After a setting process, the set silicone is at least partially removed, so that the inside of the partition, including the openings in the partition, are covered with the silicone. The membrane or foil is elastic and thus stretchable. The elastic foil or membrane can preferably deviate at least in sections through the opening in the partition wall and exert a force on the elastic ring element directly or indirectly.

According to a preferred development of the invention, it is provided that a force transmission element is arranged and/or formed at least in sections in the opening of the partition wall. The force transmission element can thus provide a connection between the elastic ring and the cushion or the elastic ring and the foil or the membrane, so that there is an operative connection between the eleatic ring element and the cushion or the elastic ring element and the membrane. In this way, the elongation of the pad, foil or membrane can be reduced to exert a force on the elastic ring since no expansion of the pad, foil or membrane over the entire opening depth is required. Thus, the longevity of the pad, film or membrane can be increased.

The force transmission element preferably has greater strength than the elastic ring. Due to the higher strength, the force to be transmitted can be transmitted without significant losses.

An advantageous development of the invention is that the groove has a groove depth and the elastic ring element has a ring thickness, the ring thickness in an initial state of the elastic ring element being equal to the groove depth or greater than the groove depth. In other words, the groove has a groove depth, with the groove depth extending in a direction perpendicular to the longitudinal direction of the punch. The elastic ring element is arranged in the groove and has a ring thickness, the ring thickness also relating to a direction which is aligned perpendicularly to the longitudinal direction of the punch. If the ring element is arranged in the groove and is not operatively connected to the pressure element, the ring thickness is equal to or greater than the groove depth. As a rule, it is provided that the ring thickness is slightly larger than the groove depth. In this way, even when the pressure element is not acted upon, a small sealing effect of the stamp head can be achieved via the elastic ring element with respect to an inner wall of a hollow shaft in which the stamp is arranged so that it can move axially.

It is advantageously provided that a soffit of the opening in the dividing wall is designed in the shape of a valley and/or rounded. In this way, sharp edges in the area of the opening can be avoided, so that the risk of damage to the pressure element when it expands and escapes through the opening can be reduced.

An advantageous development of the invention is that the partition has a plurality of openings. The plurality of openings are spaced apart from one another at regular intervals in the circumferential direction of the punch head. In this way, a substantially uniform seal against an inside a hollow shaft in which the stamp is arranged in an axially displaceable manner.

The invention also relates to a use of the punch according to the invention in an injection molding device for overmolding semiconductor components, the punch being arranged in a hollow shaft so that it can be displaced in the axial direction of the hollow shaft, and the ring element being able to be clamped and/or sealed against an inside of the hollow shaft at least in sections when pressure is applied .

Furthermore, the invention relates to an injection molding device for encapsulating semiconductor components of a transmission control unit with the stamp according to the invention.

Further features and advantages of the present invention result from the dependent claims and the following exemplary embodiments. The exemplary embodiments are not intended to be limiting, but rather to be understood as exemplary. They are intended to enable those skilled in the art to carry out the invention. The applicant reserves the right to make individual and/or several of the features disclosed in the exemplary embodiments the subject of patent claims or to include such features in existing patent claims. The exemplary embodiments are explained in more detail with reference to drawings.

• 1 einen Längsschnitt durch einen Stempel im Bereich des Stempelkopfes gemäß einem bevorzugten Ausführungsbeispiel der Erfindung;
• 2 einen Querschnitt durch den Stempelkopf gemäß dem bevorzugten Ausführungsbeispiel der Erfindung;
• 3 einen Längsschnitt durch den Stempel im Bereich des Stempelkopfes mit einem mit Druck beaufschlagten Druckelement in einer Kammer des Stempelkopfes gemäß dem bevorzugten Ausführungsbeispiel der Erfindung;
• 4 einen Längsschnitt durch den Stempel im Bereich des Stempelkopfes mit einem mit Druck beaufschlagten Druckelement in einer Kammer des Stempelkopfes gemäß einem weiteren bevorzugten Ausführungsbeispiel der Erfindung.

In these show:

• 1 a longitudinal section through a stamp in the area of the stamp head according to a preferred embodiment of the invention;
• 2 a cross section through the stamp head according to the preferred embodiment of the invention;
• 3 a longitudinal section through the stamp in the area of the stamp head with a pressurized pressure element in a chamber of the stamp head according to the preferred embodiment of the invention;
• 4 a longitudinal section through the stamp in the area of the stamp head with a pressurized pressure element in a chamber of the stamp head according to a further preferred embodiment of the invention.

In 1 a longitudinal section through a stamp 10 for an injection molding device (not shown) is shown. The stamp 10 comprises a stamp rod 12 with a media channel 14 formed within the stamp rod 12 . The stamp rod 12 is designed in a straight line or runs along a longitudinal axis 16 . The media channel is arranged coaxially to the longitudinal direction or longitudinal axis 16 of the plunger rod 12 .

The plunger rod 12 has a distal end 18 . A punch head 20 is arranged at the distal end 18 of the punch rod 12 . A chamber 22 is formed within the punch head 20 , the chamber 22 being directly or indirectly connected and/or coupled to the media channel 14 . A peripheral groove 26 is formed on an outer side 24 of the punch head 20 . A groove depth of the groove 26 is arranged and/or formed in a direction perpendicular to the longitudinal axis 16 of the punch 10 or the punch rod 12 . The chamber 22 formed in the punch head 20 and the circumferential groove 26 are separated from one another by at least one partition 28 . The partition wall 28 is formed all around. A plurality of spaced-apart, edge-closed openings 30 are formed in the partition wall 28 . The openings 30 thus establish a connection between the groove 26 and the chamber 22 . An elastic ring element 32 is arranged in the groove 26 . Furthermore, an expandable pressure element 34 is arranged and/or formed in the chamber 22 , the pressure element 34 being connected to the media channel 14 of the plunger rod 12 in a media-tight manner and/or in terms of media technology. In this way, a pressure medium, for example a gaseous medium such as air, or a fluid, can be supplied to the pressure element 34 via the media channel 14 . In the present case, the pressure element 34 is designed in the form of a cushion.

The ram head 20 has a multi-part design and has at least one connecting part 36 and one sealing part 38 , the connecting part 36 being arranged between the sealing part 38 and the ram rod 12 . The sealing part 38 has the circumferential groove 26 and at least largely forms the chamber 22 . Due to the multi-part design of the punch head 20, the pressure element 34 can be inserted into the chamber 22 of the sealing part 38 in a simple manner. In this way, the entire punch head 20 can be assembled easily.

The connecting part 36 is screwed onto the distal end 18 of the plunger rod 12 . For this purpose, corresponding first threads 40 are formed on the distal end 18 of the plunger rod 12 and on an end face of the connecting part 36 facing the plunger rod 12 . If the entire punch head 20 is worn, it can easily be detached from the punch rod 12 and replaced via the screw connection. In this way, the operating costs of the stamp 10 or the injection molding press device be reduced because wearing parts can be easily replaced.

A first centering device 42 is arranged on the distal end 18 of the plunger rod 12 and on the first end face of the connecting part 36 so that the plunger head 20 can be aligned coaxially with the longitudinal axis 16 of the plunger rod 12 . The first centering device 42 includes a circumferential fold that is formed on a face of the distal end 18 that faces the punch head 20 . In addition, the connecting part 36 has a corresponding material recess in the form of a counter-fold on the end face facing the plunger rod 12, so that the fold of the distal end 18 can engage in the counter-fold. In this way, a high degree of centering accuracy between the punch head 20 and the punch rod 12 can be made possible.

The ram rod 12 and the ram head 20 are each configured in a cylindrical shape, with the ram head 20 being arranged coaxially with the ram rod 12 . An outside diameter of the punch head 20 is larger than an outside diameter of the punch rod 12.

The sealing part 38 is screwed onto the connecting part 36 via a second thread device 44 and a second centering unit 46 . Thus, before the sealing part 38 is fastened onto the connecting part 36, the pressure element 34 can be arranged in the chamber 22 first. The chamber is limited in the longitudinal direction 16 of the stamp 10 by screwing the sealing part 38 onto the connecting part 36 . The pressure element 34 is consequently arranged in the chamber 22 and cannot escape from the chamber 22 in its longitudinal direction 16 .

The second centering device 46 is designed in the form of a fold. For this purpose, a peripheral fold is preferably formed on an end face of the connecting part 36 facing the sealing part 38 . Corresponding to this circumferential fold, a circumferential projection or a counter fold is formed on an end face of the sealing part 38 which faces the connecting part 36 . The projection engages in the circumferential fold and in this way centers the connecting part 36 and the sealing part 38 with respect to one another.

The groove 26 has the groove depth and the elastic ring element 32 has an annular thickness, the annular thickness being greater than the groove depth in an initial state of the elastic annular element 32 . In other words, the groove 26 has a groove depth, with the groove depth extending in a direction perpendicular to the longitudinal direction 16 of the stamp 10 . The elastic ring element 32 is arranged in the groove 26 and has a ring thickness, the ring thickness also relating to a direction which is aligned perpendicularly to the longitudinal direction 16 of the punch 10 . When the ring element 32 is positioned in the groove 26 and is not in operative connection with the pressure element 34, the ring thickness is greater than the groove depth. In this way, even when the pressure element 34 is not acted upon, a small sealing effect of the stamp head 20 can be achieved via the elastic ring element 32 in relation to an inner wall of a hollow shaft in which the stamp 10 is arranged in an axially displaceable manner.

2 shows a cross section through the punch head 20 at the level of the chamber 22. The chamber 22 has a circular cross section and is delimited in the radial direction by the ring-shaped partition 28, in particular by an inner side 48 of the partition 28 that points inward in the radial direction. The groove 26 adjoins an outer side 50 of the partition wall 28 directed outwards in the radial direction of the punch head 20 . The outside 50 thus forms a groove base 52 of the groove 26 .

In the partition wall 28, the plurality of openings 30 are arranged at regular intervals from one another. An opening 30 is closed at the edge and extends from the inside 48 to the outside 50. A reveal 54 of an opening 30 in the partition wall 28 is in particular, starting from the inside 48, formed in a valley shape and/or rounded. In this way, sharp edges in the area of the opening 30 can be avoided, so that the risk of damage to the pressure element 34 when expanding and yielding through the opening 30 can be reduced.

In 3 is a longitudinal section through the from 1 known stamp 10 shown. In contrast to 1 is in 3 the pressure element 34 is acted upon so that it bears against the inner wall 48 of the partition wall 28 and deviates at least in sections through the opening 30 and exerts a force 56 on the ring element 32 . In this way, the ring element 32 is shifted at least in sections in a direction perpendicular to the longitudinal direction 16 of the stamp 10 . The pressure for applying the pressure element 34 can be via a fluid or a gas, such as air.

The at least partial displacement of the elastic ring element 32 in the direction perpendicular to the longitudinal direction 16 of the ram 10 can - if the ram 10 is arranged in a hollow shaft of an injection molding device - sealing and/or bracing of the ring element 32 against an inside of the hollow shaft be made possible. Due to the fact that the pressure element 34 can be pressurized on the one hand and the pressure can also be released again, the contact pressure of the elastic ring element 32 on the inside of the hollow shaft can be changed and/or adjusted. When the stamp 10 is displaced within the hollow shaft in the longitudinal direction of the hollow shaft, the abrasiveness of the stamp 10 can thus be reduced, so that the longevity of the stamp 10 or its service life is increased.

In 4 a longitudinal section through the punch 10 according to a further exemplary embodiment is shown. Opposite the in 1 and 3 stamp 10 shown, the stamp 10 differs in the 4 in the formation of the pressure element 34. In the 4 the pressure element 34 has an annular elastic membrane. The membrane is preferably made from silicone, in particular from a two-component silicone, and seals against the inside 48 of the partition 28 . The silicone can preferably be cast onto the inner side 48 of the partition 28 . A force transmission element 58 is arranged in the opening 30 of the partition wall 28 so that the elastic membrane is in operative connection via the force transmission element 58 with the elastic ring element 32 arranged in the groove 26 .

If a pressure medium is now supplied to the chamber 22 via the media channel 14 and pressure is built up in the chamber 22, this acts against the pressure element 34 designed as an elastic membrane. In the region of the openings 30, the membrane is stretched. Due to the stretching, the membrane deviates at least in sections in a direction perpendicular to the longitudinal direction 16 of the stamp 10 into the opening 30 and acts against the force transmission element 58. In particular, a force 56 is exerted on the force transmission element 58. The force transmission element 58 is displaced in a direction perpendicular to the longitudinal direction 16 of the punch 10 and transmits the force 58 to the elastic ring element 32, as a result of which this is also displaced at least in sections in the direction perpendicular to the longitudinal direction 16 of the punch 10.

Claims (18)

Stamp (10) for an injection molding device, comprising a plunger rod (12) with a media channel (14) formed within the plunger rod (12), a stamp head (20) arranged at a distal end (18) of the stamp rod (12), wherein a chamber (22) connected to the media channel (14) is formed inside the stamp head (20), on an outer side (24) of the stamp head ( 20) a circumferential groove (26) is formed, the chamber (22) and the groove (26) being separated from one another by a partition wall (28) having at least one opening (30), an elastic ring element (32) arranged in the groove (26), and a pressure element (34) arranged and/or formed in the chamber (22), with the pressure element (34) exerting a force (56) directly or indirectly on the ring element (32) via an applied pressure, so that this is at least partially converted into a Direction perpendicular to the longitudinal direction (16) of the stamp (10) is displaceable. stamp after claim 1 , characterized in that the media channel (14) is formed coaxially to the longitudinal axis of the plunger rod. Stamp according to one of the preceding claims, characterized in that the stamp head (20) is arranged on the distal end (18) of the stamp rod (12) in a materially, form-fitting and/or non-positive manner. Stamp according to one of the preceding claims, characterized in that the stamp head (20) is aligned coaxially to a longitudinal axis (16) of the stamp rod (12) via and/or with the aid of a first centering device (42). Stamp according to one of the preceding claims, characterized in that the stamp rod (12) and the stamp head (20) are each cylindrical, the stamp head (20) is arranged coaxially to the stamp rod (12), and an outer diameter of the stamp head (20) is larger is than an outside diameter of the punch rod (12). Stamp according to one of the preceding claims, characterized in that the stamp head (20) is constructed in several parts and has at least one connecting part (36) and one sealing part (38), the connecting part (36) between the sealing part (38) and the stamp rod ( 12) is arranged, and at least the sealing part (38) forms the circumferential groove (26) and/or the chamber (22). stamp after claim 6 , characterized in that the connecting part (36) delimits the chamber (22) on a side of the chamber (22) facing the plunger rod (12). stamp after claim 6 or 7 , characterized in that the connecting part (36) and the sealing part (38) are connected to one another in a form-fitting, force-fitting and/or cohesive manner. Stamp after one of the Claims 6 until 8th , characterized in that the connecting part (36) and the sealing part (38) are aligned centered on one another via a second centering device (46). Stamp according to one of the preceding claims, characterized in that the pressure element (34) is designed in the shape of a cushion and has a socket which at least partially extends into the media channel (14) of the stamp rod (12) and/or an extension of the media channel (14) in the stamp head (20) protrudes. Stamp according to one of the preceding claims, characterized in that the pressure element (34) has a circular configuration in a cross section perpendicular to the longitudinal direction (16) of the stamp (10). Stamp after one of the Claims 1 until 9 or 11 , characterized in that the elastic pressure element (34) is designed as a circular, elastic membrane or elastic film which bears against an inner side (48) of the partition (28) and/or seals with it. Stamp according to one of the preceding claims, characterized in that a force transmission element is arranged and/or formed at least in sections in the opening (30) of the partition wall (28). Stamp according to one of the preceding claims, characterized in that the groove (26) has a groove depth and the elastic ring element (32) has a ring thickness, the ring thickness being equal to or greater than the groove depth. Stamp according to one of the preceding claims, characterized in that a reveal (54) of the opening (30) in the partition (28) is designed in the shape of a valley and/or rounded. Stamp according to one of the preceding claims, characterized in that the partition wall (28) has a plurality of openings (30). Use of a stamp (10) according to one of the preceding claims in an injection molding device for encapsulating semiconductor components, wherein the stamp (10) is arranged in a hollow shaft so that it can be displaced in the axial direction of the hollow shaft, and the elastic ring element (32) against a pressure at least in sections Inside of the hollow shaft can be braced and/or sealed. Injection molding device for encapsulating semiconductor components with a stamp (10) according to one of Claims 1 until 16 .

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