SETTING HEAD, SHEET METAL PRESS OR SETTING DEVICE WITH THIS SETTING HEAD AND A JOINING METHOD OF A JOINING ELEMENT WITH THE SETTING HEAD

Description

1. Field of the invention

[0001] The present invention relates to a setting head for a joining device, in particular a press or a setting tool, with which a joining element, such as a welding auxiliary joining part, a self-piercing rivet, or a bolt, can be joined into at least one component. Furthermore, the present invention relates to a sheet metal press or a setting tool in combination with this setting head. Finally, the present invention discloses a joining method for a joining element, in particular a welding auxiliary joining part, with this setting head. 2. Background of the invention

[0002] In the prior art, various joining devices with a setting head are used. These serve to insert a joining element. A corresponding example is a self-piercing riveting tool for setting a self-piercing rivet, for example, into a stack of two sheet metal components. Furthermore, such setting heads are used in clinching or in setting or inserting joining elements to produce a component composite.

[0003] Taking a self-piercing riveting tool as an example, the hydraulically, pneumatically, or electrically driven punch moves through a joining channel to set a self-piercing rivet. Before the setting process begins, the self-piercing rivet is often pneumatically advanced under the punch's surface within the joining channel. From this position, where the self-piercing rivet is held, for example, by a braking mechanism or other means, the working surface of the punch pushes the self-piercing rivet forward through the joining channel in the joining direction and finally presses it into the component.

[0004] To ensure the joining elements are correctly positioned within the components, they must be properly oriented in the joining channel of the setting head. Furthermore, it is essential that the orientation of the joining element is maintained throughout the movement of the punch in the joining direction, i.e., during the setting process, to create a reliable joint. If the joining element rotates or reorients itself within the joining channel, not only can the joint be poor, but the setting head, the joining channel, or the punch surface can also be damaged. This leads not only to scrap parts but also to potential downtime of the joining device for maintenance of the setting head.

[0005] To avoid such situations, WO 93 / 19890 discloses a holding device for holding, guiding, and automatically releasing joining and auxiliary joining elements, such as nuts, bolts, and rivets, in a device for pressing or fastening the joining elements to a sheet metal part. The main objective of this device is to maintain a position defined by the feed of the joining element until the element is actually pressed into a component. For this purpose, two holding jaws are pivotably mounted on the punch moving in the joining channel of the setting head. In this way, the holding jaws can pivot between a closed position, in which they hold the joining element on the punch, and an open position, in which they release the joining element from the closed position.A positive guidance system for the holding jaws ensures that, at a specific position of the punch, the holding jaws pivot in a defined manner to move from the closed to the open position. This positive guidance is achieved through the specific shape of the inner wall of the joining channel and the specific shape of the outer surface of the holding jaws adjacent to the inner wall. Since the holding jaws are attached to the punch, they move continuously with it. Consequently, there is constant friction between the punch assembly with the holding jaws and the inner wall of the joining channel. The forces acting during insertion, which also cause the holding jaws to open and close, result in critical wear. Depending on the degree of wear, this can lead to the joining element being lost uncontrollably from the closed position, resulting in a poor joint and / or damage to the punch and the insertion head.

[0006] A similar design is described in EP 0 755 749 B2. Here, too, the punch of a press-type setting head is guided in a fixed joining channel of the setting head. The joining channel, like the punch, has a rectangular cross-section. On two opposing inner surfaces, axially displaceable retaining fingers are provided in corresponding recesses. These retaining fingers are positively limited in their axial movement relative to the punch, as they engage simultaneously in opposing recesses on the outside of the punch and on the inside of the joining channel. The joining element is fed laterally into the joining channel, away from the punch exit opening. There, the joining element is held by laterally displaceable balls or ridges in the retaining fingers on one side and by the punch surface on the other.

[0007] A disadvantage is that the punch can only release the joining element from the retaining fingers if the blocking balls or ridges are released by a further clearance on the inside of the joining channel. Tolerances in the height of the joining element, in particular, can lead to additional frictional forces and wear between the retaining fingers and the joining channel. Furthermore, the joining element is released from the retaining fingers at a distance from the component. Consequently, it can tilt under the punch surface or generally reorient itself, resulting in a defective joint. Another disadvantage is that the punch, in combination with the retaining fingers, moves within the joining channel under constant friction with the inner surface. This leads to wear, contamination in the joining channel, and the development of tolerances in the freedom of movement of the retaining fingers. Therefore, this design is associated with high maintenance costs.Furthermore, the risk of insufficient positioning of the joining elements and unreliable retention of the joining element increases prior to the formation of a joint. Inadequate retention of the joining element does not guarantee the necessary resistance to loss, especially when operating a setting head in combination with a press. This resistance to loss is of particular importance due to the high forces exerted by a press in the two- to three-digit ton range. A lost or mispositioned joining element often results in significant damage to the press and costly, maintenance-intensive downtime for the press or a processing line with multiple presses.

[0008] Improvements relating to a feeding mechanism for objects are described in GB 825 223 A, which forms the basis for the preamble of claim 1. In this device, nuts are fed to a driven tool. The nuts are fed from the hopper into the recess for use by the pneumatic screwdriving tool, the nuts being moved by the device and falling from the upper chute in an edge-to-edge position into the lower chute, which has a telescopic relationship to the upper chute, where they are released individually by the lever according to the tool's requirements. The tool with the drive insert is pressed into position by the operator against a nut, and this downward movement of the tool accomplishes four things in succession: First, it engages, by means of a cup, with the pulley of the lever to displace its end, thus clearing the path for the insert.Second, it engages the lever, causing the stack of nuts to fall into the lower chute until it is held by the lever's tip. Third, it engages the lever's rollers to pull its ends out from under the positioned nut. Fourth, once the nut is engaged, the insert drives it in. As the downward pressure on the tool is released, the subsequent lever movement releases the next nut, which falls and is positioned by the lever ends, which return to their original positions, ready for the next work cycle.

[0009] The object of the present invention is therefore to propose an alternative setting head for a press or joining device which ensures a reliable supply of a joining element and a subsequent joining process without the aforementioned disadvantages. 3. Summary of the invention

[0010] The above problem is solved by a setting head for a joining device, in particular a press or a setting tool, according to independent claim 1, by a sheet metal press or a setting tool with this setting head according to independent claims 7 and 8, and by a joining method of a joining element, in particular a welding auxiliary joining element, with this setting head according to independent claim 9. Advantageous embodiments and further developments of the present invention will become apparent from the following description, the accompanying drawings, and the appended claims.

[0011] The setting head according to the invention for a joining device has the following features: a longitudinally movable punch, such that a joining element can be inserted into a component via a punch surface arranged at a working end of the punch; a receiving sleeve, which preferably has a hollow cylindrical design or a block-like shape with an inner channel, with a through-channel, which is guided concentrically and axially movable on the punch in the through-channel adjacent to the working end of the punch; and two holding arms arranged opposite each other and outside the through-channel on the receiving sleeve, each providing at least one laterally projecting holding end, so that the joining element can be detachably positioned with the at least two holding ends adjacent to an outlet opening of the through-channel facing away from the punch and through the axially movable working end of the punch.

[0012] The setting head according to the invention is characterized by a combination of the movable punch with a receiving sleeve. The receiving sleeve has a hollow cylindrical shape, enabling it to accommodate the punch in a through-channel. In this context, "hollow cylindrical" refers to the presence of an inner channel and an outer surface that runs parallel to it, at least in sections. The inner channel, also called the through-channel, preferably has a round or non-round cross-section. A punch (see below) of a complementary shape is guided within it.

[0013] Within the through-channel, the punch is largely free to move axially. Only a positive-locking connection between the receiving sleeve and the punch ensures that the relative movement of the punch and receiving sleeve is limited to a specific distance or length. This limited relative travel between the receiving sleeve and the punch ensures, on the one hand, that the punch can assume a rest position for the insertion of a new joining element. Furthermore, this limited relative displacement ensures that the punch reaches a working position relative to the receiving sleeve, allowing for the reliable insertion of a joining element.

[0014] In addition to receiving the punch in the through-channel, the receiving sleeve serves to receive and hold a joining element in preparation for a joining or setting operation adjacent to the exit opening of the through-channel. During a setting operation of the punch, the working end of the punch preferably passes through the exit opening, thereby taking the pre-positioned joining element with it and pressing it into the adjacent component. This preferred pre-positioning of the joining element is ensured by retaining arms that are attached to the receiving sleeve outside the through-channel and any joining channel of the setting head. In this way, the retaining arms, the punch, and the inner wall of the through-channel can move independently of one another, thus minimizing wear and friction losses of components moving in mutual contact.

[0015] Nevertheless, the retaining arms arranged outside the through-channel are appropriately shaped to position the joining element in the joining direction, ideally before the end of the working area or before the punch surface, and to adequately prepare for an upcoming joining process. For this purpose, a functional end of each retaining arm, which holds the joining element, projects under the punch in the joining direction, thus keeping the joining element releasably ready for the punch surface to engage. The corresponding holding position of the joining element is preferably located inside or outside the through-channel of the receiving sleeve.

[0016] Another advantage of arranging the retaining arms outside the through-channel is their easy accessibility. In the event of wear, these retaining arms can be easily replaced due to their accessibility, which reduces downtime of a press or setting machine compared to conventional setting head designs.

[0017] According to the invention, the receiving sleeve is spring-loaded relative to the punch and is movable to a limited extent in the longitudinal direction of the punch, so that in a rest position of the punch the working end of the punch is arranged inside the through channel and away from its exit opening and in a working position of the punch adjacent to the exit opening, preferably inside or outside the through channel.

[0018] The receiving sleeve and the punch are preferably positively connected to each other in such a way that a certain degree of relative movement in the longitudinal direction of the punch is ensured. This relative movement ensures that the punch can assume a rest position and a working position. Depending on the rest position and the working position of the punch, the receiving sleeve must also be positioned appropriately, as its position must, on the one hand, ensure the unimpeded feeding of a new joining element, and on the other hand, ensure the positioning of the joining element under the punch surface and thus a smooth joining process. The preferably used positive-locking connection between the receiving sleeve and the punch also limits the extent of the relative movement to a preferred minimum, so that a minimum of time and space is required for the relative displacement of the punch and receiving sleeve with respect to each other.This, in turn, has a particularly favorable effect on the cycle times achievable with a joining device when producing several successive joints. For setting a welding auxiliary joining element or, more generally, a group of joining elements, it is preferred if the punch, with its preferred punch surface, does not leave the through-channel until the joining process is completed. Accordingly, in this preferred embodiment, the punch surface does not pass through an outlet opening of the through-channel of the receiving sleeve. This arrangement is preferably used when the setting head is operated in a press. According to a further preferred embodiment of the present invention, the punch passes through the outlet opening of the through-channel of the receiving sleeve until the joining process of a joining element into a component is completed.This design is particularly advantageous when a setting head is removed laterally from the joining point after joining, thus preventing the head of the joining element from colliding with the receiving sleeve.

[0019] According to the invention, the receiving sleeve and the punch are guided together in a form-fitting manner, so that the receiving sleeve can be axially displaced relative to the punch without rotation.

[0020] As mentioned above, the preferred positive-locking connection between the receiving sleeve and the punch effectively limits any relative misalignment between them. Furthermore, this positive locking mechanism prevents any relative rotation between the receiving sleeve and the punch. In this way, the pre-positioned joining element maintains its orientation and alignment with respect to the working end of the punch. Moreover, limiting relative movement between the receiving sleeve and the punch to only the necessary minimum results in minimal wear and associated friction losses. This also has a positive impact on the maintenance requirements during subsequent operation.

[0021] According to the invention, the retaining arms are also L-shaped, and a shorter leg of the L projects laterally inwards into the through-channel of the receiving sleeve with a retaining-release contour for the joining element. According to an alternative embodiment not in the invention, the shorter legs of the L, by virtue of their laterally inward orientation, position the retaining-release contour for the joining element adjacent to the exit opening, but preferably outside the through-channel of the receiving sleeve.

[0022] The L-shaped retaining arms according to the invention are attached to the outside of the receiving sleeve. This ensures the easy accessibility and effortless replaceability already discussed above. Furthermore, this arrangement ensures that the movement of the plunger in the through-channel of the receiving sleeve is not impaired or hindered by the retaining arms. According to the invention, the retaining arms have the L-shape already mentioned above, so that the shorter leg of the L can be used to provide the retaining-release contour for the joining element. This retaining-release contour ensures that an added joining element is reliably held between the laterally projecting retaining ends by means of a positive-locking and / or force-locking connection of the retaining contour.Since the retaining ends preferably hold the joining element in a radially inwardly resilient manner, a force-fit connection between the retaining ends and the joining element, which can be easily released by the punch, ensures reliable pre-positioning of the joining element before the working end of the punch. According to the invention, a retaining contour is incorporated into the...

[0023] Retaining ends are provided which are adapted in their shape to the joining element to be fixed, so that the force-fit connection between joining element and retaining ends is supported by an additional form-fit connection.

[0024] The release contour, also provided at the retaining ends, is shaped in accordance with the movement of the joining working end of the punch. During the joining process, the working end, and specifically the punch surface with the joining element, moves between the retaining ends to release the joining element from the retaining-release contour and subsequently insert it into the component. In this context, it is preferred according to the invention if planes inclined towards each other in the joining direction are provided at the retaining ends, so that the axial movement of the punch in the joining direction pushes the retaining ends radially outwards through the joining element and / or the working end of the punch. With this preferred design, the release movement of the working end of the punch for the joining element from the connection with the retaining ends can be integrated as continuously as possible into the joining movement of the joining element into the component.

[0025] According to the invention, the holding-release contour has at least a positive-locking retention for the joining element and an inclined release surface arranged at an acute angle to the joining direction for the punch-side release of the joining element from the holding-release contour. This specific geometric design of the retaining ends was already discussed qualitatively in the preceding paragraph.

[0026] According to a further preferred embodiment of the present invention, a longer L-leg of the L-shaped retaining arm provides a fastening structure with which the L-shaped leg can be interchangeably attached to the receiving sleeve.

[0027] Preferably, the L-shaped retaining arm is formed by a leaf spring. The longer leg of this leaf spring is attached to the outside of the mounting sleeve. Such a connection can be achieved, for example, by a screw connection or a snap-fit ​​connection, which can be easily loosened and tightened for necessary maintenance.

[0028] According to a further preferred embodiment of the setting head according to the invention, the receiving sleeve has a profile track open on one side adjacent to the exit opening of the through channel, which is formed at least partially on opposite sides by the retaining ends and with which the joining element can be supplied to a joining position in the joining direction under the punch surface of the punch.

[0029] According to the invention, preferably the laterally or radially inwardly projecting retaining ends of the retaining arms define a pre-position of the supplied joining element adjacent to the outlet opening of the through-channel. Accordingly, the retaining ends are preferably arranged such that the pre-positioned joining element, held by the retaining ends, is located within the through-channel and adjacent to the outlet opening, or outside the through-channel and adjacent to the outlet opening. To position the joining element with the retaining ends within the through-channel, the receiving sleeve has suitable recesses or windows. These recesses or windows are penetrated laterally inward by the retaining ends to hold the joining element.This preferred different pre-position of the joining element due to the corresponding arrangement of the holding ends is preferably chosen with reference to the component to be joined, the available space conditions on the component, the protection of the joining element in the holding position due to external influences or taking into account other external parameters.

[0030] Preferably, the opposing retaining ends form part of a profile track along which the joining element can be moved to a suitable pre-position for the upcoming joining process. According to a further preferred embodiment in this context, the retaining ends at least partially form a receiving recess for the joining element to be moved. This receiving recess defines the pre-position to be assumed by the joining element.

[0031] According to a further preferred embodiment of the present invention, the retaining ends are elastically spring-loaded laterally into the passage channel via the retaining arms. This preferred design solution is based on providing the L-shaped retaining arms, preferably as leaf springs, which, due to their material properties and design, provide the elastic spring preload of the retaining arms.

[0032] According to a further preferred embodiment of the setting head according to the invention, the profile track open on one side in combination with the spring-loaded retaining ends forms the receiving recess for a joining element, into which the joining element can be moved via a mechanical actuator.

[0033] According to the invention, preferably the joining element is injected into the setting head via a profiled hose using compressed air. It is also preferred to utilize gravity to feed the joining element to the setting head via a suitable arrangement. Preferably, the injected joining element is initially positioned adjacent to the punch or an adapter piston of the setting head, which is in a working position. Accordingly, the punch, adapter piston, or another part of the setting head blocks the receiving recess, preventing the joining element from moving into it. As soon as the receiving recess is clear for the insertion of a joining element, the mechanical actuator moves the joining element into the pre-position, preferably into the receiving recess.

[0034] Such a mechanical actuator preferably consists of a pneumatically, hydraulically, or electrically driven lever mechanism, for example, a toggle lever mechanism. During operation of the actuator, the joining element is moved by the actuator in such a way that the actuator places the joining element into the receiving recess. Since the position of the actuator can preferably be detected during its movement, or a maximum travel distance of the actuator can be monitored by sensors or detected control signals, it is preferably possible to deduce whether the joining element has reached the desired pre-position in the receiving recess. Accordingly, if the receiving recess is not reached, error messages can be used to define actions that restart the feeding of the joining element to the receiving recess, investigate or indicate a mispositioning of the joining element, or initiate troubleshooting in combination with feeding the joining element.

[0035] Therefore, according to the invention, it is preferred to carry out a movement of the actuator in a position-monitored manner, so that the positioning of the joining element in or outside the receiving nest can be detected and / or determined.

[0036] The present invention also comprises a sheet metal press in combination with a setting head according to the preferred embodiments described above.

[0037] Furthermore, the present invention comprises a setting device with a setting head according to the preferred embodiments described above.

[0038] The present invention further discloses a joining method for an joining element, in particular a welding aid component, with a setting head as described above according to different embodiments. The joining method comprises the following steps: with the punch in a rest position, moving an joining element into a holding position between the holding ends of the holding arms; moving the punch from the rest position into a joining direction, wherein the joining element is positioned at a distance in front of the punch surface of the working end of the punch in the holding position; placing the receiving sleeve, preferably directly or indirectly via the pre-positioned joining element, onto a component; then moving the punch in the through-channel relative to the receiving sleeve and against the spring preload between the punch and the receiving sleeve; releasing the joining element from the holding position between the holding ends with the working end of the punch; and inserting the joining element into the component.

[0039] The joining method described above is characterized by the interaction of the various structural elements of the preferred setting head according to the invention. Therefore, it is also preferred within the joining method to move the joining element into the holding position by means of an actuator. As a further step of the preferred joining method according to the invention, it is preferred to feed a new joining element into a pre-position adjacent to the receiving recess via an element feeder, in particular a profile tube, while the punch blocks the receiving recess. It is equally preferred that, in the working position of the punch, another part of the setting head blocks the receiving recess for the feeding of the joining element. This is preferably the adapter piston.

[0040] Furthermore, according to the invention, it is preferred in the present joining method to move the punch from a working position for joining the joining element to the rest position, wherein the punch, supported by the spring preload between the punch and the receiving sleeve, is at least partially removed from the through-channel, preferably from an exit opening of the through-channel of the receiving sleeve, in a form-fitting manner.

[0041] The preferably positive-locking connection between the receiving sleeve and the punch ensures the minimal relative offset between the receiving sleeve and the punch, as discussed above. This ensures that the punch can be moved back and forth between the rest position and the working position with minimal displacement. Simultaneously, this offset ensures that, in the rest position, the punch can preferably feed a joining element into the receiving recess in its pre-position. In the working position of the punch, it is again guaranteed that the joining element is reliably inserted into a component from the receiving recess. If, in this context, the punch is moved to the rest position either directly via a drive or indirectly via a structural component, such as preferably the adapter piston or similar, the punch is partially displaced from the through-channel of the receiving sleeve in the opposite direction to the joining direction.In other words, the working end of the punch is moved away from the exit opening of the through-channel of the receiving sleeve. If the punch is moved into the working position directly via a drive or indirectly via a structural component in the joining direction—i.e., if an insert is placed into a component—the punch is moved further into the through-channel in the joining direction. During the final insertion of the insert into the component, the working end of the punch is located in the through-channel adjacent to the exit opening, is flush with it, or protrudes slightly beyond it. 4. Brief description of the accompanying drawings

[0042] The preferred embodiments of the present invention are explained in more detail with reference to the accompanying drawing. The drawing shows: Figure 1 is a side view of a preferred embodiment of a setting head for a press; Figure 2 is a close-up of a preferred combination of the punch with a receiving sleeve in a lateral axial sectional view, in which the punch is preferably directly driven via a drive unit; Figure 3 is a perspective side view of a preferred combination of punch, adapter piston, and receiving sleeve with externally arranged retaining arms; Figure 4 is a lateral axial sectional view of a preferred combination of punch and receiving sleeve with an joining element in a pre-position and held by the retaining ends of the retaining arms, in which the punch is preferably indirectly driven via the adapter piston or another structure; Figure 5 is a lateral axial sectional view of the preferred embodiment according to Figure 4, with an joining element placed into an adjacent component by the movement of the punch, Figure 6 a schematic top view of a supplied joining element which cannot yet be moved into a pre-position due to the blockage by the adapter piston, Figure 7 a schematic view of the joining element in a sectional view positioned in front of a preferred blocked receiving nest (see Fig. 6 ) between the preferred holding ends of the holding arms, Figure 8 a schematic top view of the preferred feed of the joining element with the mechanical actuator into the joining position in the preferred receiving recess, Figure 9 a schematic sectional view of the setting head made of Fig. 8 along the feed path of the joining element and in the plane of the receiving nest, Fig. 10 a schematic sectional view of the setting head made of Fig. 8along the feed path of the joining element and in the plane of the receiving nest, while the preferred actuator moves the joining element into the receiving nest, Figure 11 a preferred axial sectional view along the punch axis, which moves the joining element into the receiving nest according to Figure 10 Figure 12 shows a flowchart of a preferred embodiment of the joining method according to the invention. 5. Detailed description of preferred embodiments

[0043] Figure 1 Figure 1 shows a setting head 1 which, in preferred embodiments, is used in various joining devices. The setting head 1 of the Figure 1The telescopic unit 3 and the schematically depicted upper beam 5 of a press (not shown) are adapted for use in a press tool. Such press tools are used, for example, in vehicle or railway car manufacturing. Besides joining an element using the setting head 1, these press tools simultaneously serve to precisely shape sheet metal parts, which, for example, form the later vehicle body.

[0044] If the sheets to be formed by the press are made of a material that is not weldable or difficult to weld, the forming head 1 preferably inserts a welding aid joining element 7 made of weldable material into the sheet simultaneously with the forming of the sheet or component. This combines work processes and facilitates further processing of the formed sheet.

[0045] In addition to its use in a press for setting a welding auxiliary joining element 7, the setting head 1 is preferably used in a setting device for self-piercing rivets, bolts, screws, nuts, for clinching, and for carrying out other known joining methods. Accordingly, the setting head 1 inserts connecting elements of various designs into at least one component 9, wherein the punch 10 of the setting head is provided to be rotatable or non-rotatable and axially movable, depending on the joining element 7 and the joining process.

[0046] The following description refers, by way of example, to the insertion of the welding auxiliary joining element 7 into a component 9. The welding auxiliary joining element 7 represents any joining element. The component 9 likewise represents either a single component or multiple components.

[0047] To prepare for a joining process, a hold-down device N is preferably placed on the at least one component 9. Alternatively, it is also preferred to hold the at least one component 9 or a plurality of components detachably on a base, a support, or an anvil by means of suitable clamping devices.

[0048] The setting head 1 is shown in greater detail in various preferred embodiments in the Figures 2 to 11 shown. It comprises an adapter piston 30 in which the punch 10 is guided in its longitudinal direction so as to be movable - i.e. axially movable.

[0049] In known joining devices, such as a self-piercing riveting tool, the adapter piston 30 forms the joining channel. The joining element is fed into this joining channel and inserted into the component by the punch 10. The punch 10 is preferably moved directly by a drive in the joining direction R and in the opposite direction. A setting head 1 with a directly driven punch is in Figure 2 This is indicated because the adapter piston 30 does not guide or indirectly drive the punch 10. In a press, the punch 10 is preferably not driven separately within the setting head 1, but is guided or moved together with the press tool. Therefore, the punch 10 is preferably driven via the adapter piston 30 (see figure). Fig. 4 ) indirectly driven. The following description of the function and construction of the setting head 1 applies equally preferably to both the direct and indirect drive options for the punch 10.

[0050] According to a preferred embodiment of the present invention, the adapter piston 30 guides and holds a receiving sleeve 50 in addition to the plunger 10. For this purpose, the adapter piston 30 has at least two stepped sections 32 and 34. These stepped sections are separated from each other by the step 36 and, according to a preferred embodiment, have guide channels of different diameters. Preferably, the plunger 10 is guided in the guide channel of section 32. The guide channel in section 34 guides the receiving sleeve 50.

[0051] The receiving sleeve 50 is guided on the punch 10, preferably adjacent to a working end 12 of the punch 10. The punch 10 and a through-channel 52 (see below) of the receiving sleeve 50 preferably have a round cross-section. Therefore, according to a preferred embodiment of the present invention, the receiving sleeve 50 is hollow cylindrical or at least hollow cylindrically shaped. Accordingly, the through-channel 52 has an inner guide wall with a round cross-section. The outer surface of the receiving sleeve 50 is also round in cross-section to be guided by the adapter piston 30.

[0052] It is also preferred, and adjustable depending on the application, for the punch 10 to have a square or generally a non-circular cross-sectional shape. This results in a cross-sectional design of the through-channel 52 of the receiving sleeve 50 adapted to the shape of the punch, in order to reliably guide the punch 10 and the receiving sleeve 50 together. The outer surface of the receiving sleeve 50, in combination with the adapter piston 30, can also be adapted accordingly in its shape.

[0053] The punch 10 is moved in a joining direction R and back via a drive (not shown) directly or via the adapter piston 30. According to various preferred embodiments of the present invention, the drive of the punch 10, and thus preferably of the joining devices, is electrical, hydraulic, pneumatic, or mechanical, or a combination thereof.

[0054] The receiving sleeve 50 is preferably guided by the punch 10 and the adapter piston 30, although guidance by the punch 10 alone would preferably also suffice. For this purpose, the working end 12 of the punch 10 is guided in the through-channel 52 of the receiving sleeve 50. The through-channel 52 is arranged concentrically to the working end 12 of the punch 10 and thus to the punch 10 as a whole.

[0055] A spring 80 is arranged between a shoulder 14 of the punch 10, which faces the receiving sleeve 50, and an end face 54 of the receiving sleeve 50, which also faces the punch 10. The spring 80, preferably a helical spring mounted on the punch 10, provides a spring bias between the punch 10 and the receiving sleeve 50. This causes the punch 10 and the receiving sleeve 50 to move apart when the working end 12 and / or the receiving sleeve 50 is relieved of load. In this context, "relieving of load" means that the punch 10 is moved in the opposite direction R after completion of a joining operation and thereby detaches from the joining element 7. The receiving sleeve 50 is relieved of load when the setting head 1 is moved in the opposite direction R, so that the receiving sleeve 50 is lifted from the component 9 or mechanically relieves the component 9.

[0056] The preload of the spring 80 ensures that, in the event of mechanical release of the receiving sleeve 50 and / or punch 10, the working end 12 of the punch 10 is partially moved out of the through-channel 52 in the opposite direction to the joining direction R. This results in a punch surface 16, with which the welding aid 7 is inserted into the component 9, moving away from an exit opening 54 of the through-channel 52. This preferably opens a feed area for the welding aid 7 adjacent to the exit opening 54 through the working end 12, as explained in more detail below.

[0057] The relative axial displacement between the punch 10 and the receiving sleeve 50, generated by the preload of the spring 80, is preferably limited along a length by a positive guide 18, 56 between the receiving sleeve 50 and the punch 10. For this purpose, a ball or projection 56 preferably engages in an axial groove 18 on the punch 10, similar to a tongue-and-groove connection. It is also preferred to provide the axial groove on the inner wall of the through-channel 52 and the projection on the punch 10. According to a further preferred embodiment, a dowel pin passes completely through a through-bore in the punch along the diameter of the punch and projects from the radial side walls of the punch 10. The projecting ends of the dowel pin each engage in a guide groove to provide linear guidance.It is understood that the positive-locking positive guidance 18, 56 also preferably prevents a relative rotation between the punch 10 and the receiving sleeve 50.

[0058] To accommodate a rotatable punch, for example for setting a screw, the axial groove 18 preferably extends completely along the circumference of the punch (not shown). A functionally similar adaptation is achievable with the combination of a dowel pin and a guide groove.

[0059] When the punch 10 is moved against the joining direction R, the preload of the spring 80 initially generates the maximum possible axial offset between the punch 10 and the receiving sleeve 50. This maximum axial offset is defined by the positive guidance 18, 56. As soon as the maximum axial offset is reached by the return movement of the punch 10 against the joining direction R – generated directly by a drive or by an indirect movement via the adapter piston 30 – the punch 10, by continuing its movement against the joining direction R, guides the receiving sleeve 50 and removes it from the component 9.

[0060] At maximum axial displacement between the receiving sleeve 50 and the punch 10, the punch 10, and preferably its working end 12 with the punch surface 16, has reached a rest position. This rest position is a preferred prerequisite for pre-positioning a joining element 7 in a receiving recess 92 (see below) adjacent to the outlet opening 54 of the through-channel 52 for a joining operation.

[0061] If the punch 10 is extended in the joining direction R and the punch surface 16 is adjacent to the exit opening 54 during a joining process, then the punch 10 and its working end 12 are in a working position. In the working position (see Figure 5bThe working end 12 blocks the receiving nest 92, preventing any joining element 7 from being fed into the receiving nest. In an alternative embodiment of the setting head 1, it is also preferred that the adapter piston 30 blocks the receiving nest 92, preventing any joining element 7 from being fed into the receiving nest 92 (see Figures 6 and 7 ).

[0062] Referring to the Figures 3 , 4 and 5 and specifically the cross-sectional images of the Figures 4b and 5bThe receiving sleeve 50 has two opposing retaining arms 60. The retaining arms 60 are preferably attached to the outside of the through-channel 52 on the receiving sleeve 50. The retaining arms 60 also preferably have an elongated shape and run parallel to the punch axis. A fastening structure 64 is provided at an end 62 of the retaining arms 60 facing the punch for fastening them. The fastening structure 64, which preferably provides suitable openings for a screw connection to the receiving sleeve 50, a snap-fit ​​connection, or a detent connection, ensures easy replacement of the retaining arms 60 in the event of wear, failure, or adaptation to a specific geometry of an joining element 7.

[0063] According to the invention, the retaining arms 60 are preferably formed by metal springs with an L-shaped form. A longer leg of the L 65 preferably has the end 62 with a fastening structure 64.

[0064] A shorter L-leg 66 extends laterally or radially inwards with respect to the longer L-leg 65 in the direction of the passage channel 52.

[0065] According to a preferred embodiment of the present invention, a retaining-release contour 68 is provided on the laterally or radially inwardly projecting end face of the shorter L-legs 66. This is because the retaining arms 60, and in particular the shorter L-legs 66, hold the joining element 7 in a preliminary position before the start of a joining process. For this purpose, the retaining-release contour 68 is adapted to detachably fasten or fix the joining element 7.

[0066] According to the invention, it is preferred that the joining element 7 is held by outer sections that are later pressed into the component 9 during the joining process. The necessary structure of the end faces of the shorter L-legs 65 releasably clamps the joining element 7 for this purpose. During the joining process, the shorter L-legs 66 with their end faces holding the joining element 7 are moved relative to the joining element 7 in a timely manner, opposite to the joining direction R and laterally to it. This prevents a collision between the L-legs 66 and the component 9. The combination of the punch 10 and the receiving sleeve 50 preferably initiates a counter-rotating movement that requires no active drive. In addition, the joining element 7 is preferably released at a point in time when it is already partially inserted into the component 9 and can no longer slip or fall out of the assembly.

[0067] Preferably, the retaining-release contour 68 engages with laterally or radially inwardly directed spring forces and preferably under a head of the joining element 7. It is equally preferred to hold the joining element 7, for example a bolt, on a shaft surface. Accordingly, the retaining-release contour 68 is preferably designed to be complementary to a retaining section on the outside of the joining element 7, wherein the retaining section on the joining element 7 is pressed into the component 9 by the joining process. Preferably, the joining element 7 is positioned in the receiving recess 92 for the joining process in a form-fit and / or force-fit manner and is releasable via the retaining-release contour 68.

[0068] Preferably, the length of the longer L-leg 65 is selected such that the shorter L-legs 66, with their retaining-release contour 68, project into the through-channel 52 adjacent to the exit opening 54. Based on this configuration, the joining element 7 is held within the through-channel 52 adjacent to the exit opening 54. This arrangement protects the joining element 7, held by the retaining arms 60, from external influences when the insertion head 1 approaches the joining point. To enable this arrangement of the shorter L-legs 66, they extend through a recess 58 in the receiving sleeve 50 (see Figure 1). Figure 3 ). This recess 58 can also be implemented as a window or opening (not shown) in the receiving sleeve 50.

[0069] Furthermore, the position of the shorter L-legs 66 is preferably chosen in coordination with the joining element 7 such that the joining element 7 protrudes slightly from the through channel 52 in the direction away from the punch or is flush with the end of the receiving sleeve 50 and the through channel 52 facing away from the punch.

[0070] How to use the cross-sectional view of Figure 4bAs can be seen, a holding surface 68A, preferably arranged parallel to the outside of the joining element 7 (here a holding surface arranged parallel to the longitudinal axis of the punch 10), holds the joining element 7, preferably the outside of the head of the joining element 7, in place. In the joining direction R, a release surface 68B adjoins the holding surface 68A. The release surface 68B preferably forms an angle of less than 90° with the longitudinal axis of the punch 10 or the joining direction R. Accordingly, the release surface 68B is arranged radially inwards and inclined in the joining direction R. The preferred arrangement of the release surface 68B causes a joining element 7, moved by the punch 10 in the joining direction R, to slide off the release surface 68B. In this process, the shorter L-legs 66 with the retaining-release contour 68 are pressed laterally or radially outwards by the joining element 7 and release the joining element 7 (see Figure 5bAs the movement of the punch 10 continues in the joining direction R, the joining element 7 is inserted into the component 9. In addition to the release function described above, the release surface 68B also performs a holding function, complementing the action of the holding surfaces 68A. The preferred release surfaces 68B engage under the head of the joining element 7 to form an axially releasable undercut in the joining direction R. This elastically or springily releasable undercut, which complements the holding surfaces 68A, preferably supports the retention of the holding ends 66. The holding surfaces 68A and the release surfaces 68B, either alone or in combination, hold the joining element 7 until the punch 10 inserts the joining element 7 from this holding-release contour 68 into the component 9.

[0071] Once the joining element 7 has been inserted and the working end 12 of the punch 10 has moved away from the working position, the shorter L-legs 66 spring back into their initial position. In the initial position, the retaining-release contour 68 of the shorter L-legs 66 is again ready to receive a joining element 7.

[0072] According to the preferred embodiment in Figure 2When the punch 10 moves in the joining direction R, the joining element 7 first rests on the surface of the component 9. It is also preferred that the receiving sleeve 50 rests on the component 9 first. This procedure can be selected to suit the joining process to be carried out and / or the joining element 7 being processed. As the punch 10 moves further in the joining direction R, the spring 80 is compressed and the punch surface 16 rests on the joining element 7 after an approach process. The receiving sleeve 50 and the punch 10 perform an opposing movement relative to each other. In this context, it is important that the positive guidance 18, 56 allows the working end 12 of the punch 10 sufficient axial clearance in the joining direction R so that the punch 10 can fully insert the joining element 7 into the component 9.

[0073] The process described above occurs in the same way even if the joining element 7 were located entirely within the through-channel 52 but adjacent to the outlet opening 54. In this case, instead of the joining element 7, the receiving sleeve 50 would first be placed on the component 9 before the process described above would take place until the joining element 7 is finally positioned.

[0074] How to use the preferred embodiment of the receiving sleeve 50 in Figure 3 As can be seen, the joining element 7 is held in a pre-position for insertion into the component 9 at the end of a profile track 90 in a receiving recess 92. The receiving recess 92 is arranged adjacent to the outlet opening 94 of the through channel 52 in the receiving sleeve 50.

[0075] Preferably, the receiving recess 92 is open only on one side. The profiled track 90 preferably connects to this opening to supply the joining element 7 to the receiving recess 92. According to a preferred embodiment of the present invention, the profiled track 90 is formed adjacent to the receiving sleeve 50 by a profiled tube 94. This profiled tube 94 preferably has a cross-sectional shape adapted to the joining element 7 in order to allow the joining element 7 to be preferably pneumatically inserted via the profiled tube 94.

[0076] According to a preferred embodiment of the profile hose 94, it has a T-shaped cross-section for head-guided joining elements 7.

[0077] To achieve short cycle times when producing multiple joints, the joining element 7 is preferably fed to the setting head 1 via the profile tube 94 while the punch 10 is in the working position. Accordingly, the working end 12 of the punch 10 or the adapter piston 30 blocks the feed path of the joining element 7 to the receiving nest 92, as shown in the Figures 6 and 7 The joining element 7 can in this case only be fed to the setting head 1 until the joining element 7 rests against the adapter piston 30 or the punch 10 (not shown).

[0078] Since the joining element 7 cannot yet be fed into the receiving nest 92, an actuator 100, preferably used for feeding the joining element 7 into the receiving nest 90, remains in its rest position.

[0079] For the feeding of the joining element 7 to the receiving nest 92, the setting head 1 is preferably moved such that the receiving nest 92, i.e. the axial end region of the receiving sleeve 50, is aligned with the profile tube 94 (see Figure 8 ). The arrow schematically illustrates the feed movement of the joining element 7 along the profile tube 94 or, more generally, a feed path.

[0080] Preferably, the joining element 7 is pressurized with air in the profile tube 94 and in the position in front of the receiving nest 92 in order to pneumatically feed it as far as possible into the receiving nest 92. Preferably, the air pressure is maintained at the fed joining element 7 for a sufficient length of time so that any possible rebound from the blocking adapter piston 30 or plunger 10 in the receiving nest 92 is reduced. According to various preferred embodiments of the present invention, the joining element 7 is pneumatically injected into the receiving nest 92 when the receiving nest 92 is free and accessible or when the receiving nest 92 is still blocked.

[0081] The shorter L-shaped legs 66 with the retaining-release contour 68, together with the receiving sleeve 50, form the receiving recess 92. Since the receiving sleeve 50 limits the receiving recess 92 relative to the profile tube 94, the joining element 7 is fed under the punch 10 and not beyond it. Furthermore, the shorter L-shaped legs 66 with the retaining-release contour 68 preferably form a continuation of the profile path of the profile tube 94 into the receiving recess 92.

[0082] Preferably, the shorter L-shaped legs 66 narrow the receiving recess 92 and thus the end of the profile track 94 to a smaller width than the joining element 7 due to the spring-loaded arrangement. Therefore, the supplying airflow in the profile tube 94 is preferably not strong enough to press or move the joining element 7 into the receiving recess 92 against the spring force of the shorter L-shaped legs 66.

[0083] For this reason, according to the invention, the actuator 100 is preferably provided, which mechanically, electromechanically, or electromagnetically moves the joining element 7 into the receiving recess 92. This is described in the Figures 10 and 11 Figure 1 illustrates where preferably a pneumatic cylinder 102 drives a toggle lever mechanism 104 to move the actuator 100. The actuator 100 is moved or rotated by the preferably pneumatic cylinder 102 until the joining element 7 is completely inserted into the receiving recess 92. In the receiving recess 92, it is then held by the retaining-release contour 68 of the shorter L-legs 66 (see Figure 1). Figure 11 ).

[0084] According to a further preferred embodiment of the present invention, the position of the actuator 100 is monitored during the feeding of the joining element 7 by the actuator 100. It is also preferred to monitor the position of the drive, preferably the pneumatic cylinder 102. This is because the position of the actuator 100 and / or the position of the drive 102 indicates whether the joining element 7 has been completely inserted into the receiving recess 92 or not.

[0085] The detected position of the actuator 100 or the detected position of the drive 102 can preferably be calibrated for the following situations: If the actuator 100 or the pneumatic cylinder 102 moves too far, there is no joining element 7 available to be inserted into the receiving recess 92. If the actuator 100 or the pneumatic cylinder 102 does not move far enough, the joining element 7 has either not reached the correct position in the receiving recess 92 between the L-shaped legs 66, or a second joining element 7 is mistakenly located in the insertion area of ​​the receiving recess 92.

[0086] After the joining element 7 has been fed into the receiving nest 92 (see Figure 10 The actuator 100 is then moved back to its rest position. The setting head 1 now moves towards component 9 and the joining process of the joining element 7 described above can begin.

[0087] Accordingly, the preferred joining method can be summarized as follows. In a first step S1, a new joining element 7 is fed into the pre-position adjacent to the receiving recess 92 via an element feeder, in particular the profile tube 94. During this step S1, the punch 10 or the adapter piston 30 blocks the receiving recess 92. It is also preferred that the joining element 7 be fed into the pre-position in front of the receiving recess 92 when the receiving recess 92 is no longer blocked.

[0088] After the punch 10 has been moved to its rest position, the joining element 7 is moved into the holding position between the holding ends 66 of the holding arms 68 (S2). Since the joining element 7 is now in the receiving recess 92, in the next step S3 the punch is moved from the rest position in the joining direction R. During this movement, the joining element 7 is positioned in the receiving recess 92, spaced apart from the punch surface 16 of the working end 12 of the punch 10. Due to the aforementioned movement of the punch 10, in step S4 the joining element 7 or the receiving sleeve 50 is then placed onto the component 9. Subsequently, the punch 10 is moved in the through channel 52 relative to the receiving sleeve 50 and against the spring preload of the spring 80 between the punch 10 and the receiving sleeve 50 (step S5).Subsequently, the joining element 7 is released from its holding position in the receiving recess 92 between the holding ends 66 by the punch 10 using the working end 16 of the punch 10 in step S6. By further moving the punch 10 in the joining direction, the joining element 7 is then inserted into the component 9 (step S7). Finally, the punch 10 is moved from its working position for inserting the joining element 7 to its rest position, whereby the punch 10, supported by the spring preload between the punch 10 and the receiving sleeve 50, is positively locked and removed from the through channel 52 (step S8). Reference symbol list

[0089] 1 Setting head 3 Telescopic unit 5 Upper beam of a press 7 Welding auxiliary joining part 9 Component 10 Punch 12 Working end of the punch 14 Shoulder 16 Punch surface 18 Axial groove, recess 30 Adapter piston 50 Mounting sleeve 52 Through channel 54 Exit opening 56 Ball, projection 58 Recess in the mounting sleeve 60 Retaining arms 62 Punch-facing end 64 Mounting structure 65 Longer L-leg 66 Shorter L-leg 68 Retaining-release contour 68A Holding surface 68B Release surface 80 Spring 90 Profile track 92 Mounting nest 94 Profile tube 100 Actuator 102 Drive 104 Toggle lever mechanism

Claims

1. A setting head (1) for a joining device, in particular a press or a setting device, having the following features: a. a punch (10) movable in longitudinal direction, so that a joining element (7) is joinable into a component (9) by a punch surface (16) arranged at a working end (12) of the punch (10), b. a receiving sleeve (50) with a passage channel (52), the sleeve being concentrically and axially movable with the punch (10) in the passage channel (52) adjacent to the working end (12) of the punch (10) on the same, and c. two holding arms being arranged opposite to each other and outside of the passage channel (52) at the receiving sleeve (50) each provide at least one laterally inwardly protruding holding end (66), so that with the at least two holding ends (66), the joining element (7) is positionable adjacent to an exit opening (54), facing away from the punch (10), of the passage channel (52) and is releasable by the axially movable working end (12) of the punch (10), wherein d. in which the receiving sleeve (50) is spring-pretensioned relative to the punch (10) and movable limitedly in the longitudinal direction of the punch (10), so that in a rest position of the punch (10), the working end (12) is arranged within the passage channel (52) and removed from the exit opening (54) and in an operating position of the punch adjacent to the exit opening (54), and e. in which the receiving sleeve (50) and the punch (10) are guided in a form-fit manner next to each other, so that the receiving sleeve (50) is axially displaceable in a rotation-free manner relative to the punch (10), characterized in that f. the holding arms (60) are provided L-shaped and a shorter L-leg (66) projects laterally inwardly with a holding-releasing contour (68) for the joining element (7) into the passage channel (52) of the receiving sleeve (50) wherein the holding-releasing contour (68) includes at least a form-fit hold (68A) for the joining element (7) as well as an inclined releasing surface (68B) arranged at a acute angle with respect to the joining direction R for the punch-sided releasing of the joining element (7) from the holding releasing contour (68).

2. The setting head (1) according to claim 1, in which a longer L-leg (65) of the L-shaped holding arm (60) provides a fastening structure (64) with which the L-shaped leg (60) is fixable interchangeably at the receiving sleeve (50).

3. The setting head (1) according to one of the preceding claims, in which adjacent to the exit opening (54) of the passage channel (50), the receiving sleeve (50) includes a profile track (90) open at one side, the track (90) being formed at least in sections at opposite sides by the holding ends (66) and with which the joining element (7) is deliverable to a joining position in the joining direction R under the punch surface (16) of the punch (10).

4. The setting head (1) according to one of the preceding claims, in which the holding ends (66) are elastically spring-pretensioned laterally into the passage channel (52) by means of the holding arms (60).

5. The setting head (1) according to claim 3, in which the profile track (90), which is open at one side, in combination with the spring-pretensioned holding ends (66), forms a receiving nest (92) for a joining element (7), into which the joining element (7) is displaceable by means of a mechanical actuator (100).

6. The setting head (1) according to claim 5, in which a movement of the actuator (100) is carried out with its position being monitored, so that a positioning of the joining element (7) inside or outside of the receiving nest (92) is determinable.

7. A metal sheet press with a setting head (1) according to one of the preceding claims.

8. A setting device with a setting head (1) according to one of the preceding claims 1 to 6.

9. A joining method of a joining element (7), in particular a welding auxiliary joining part, with a setting head (1) according to one of the preceding claims 1 to 6, having the following steps: a. with the punch (10) in a rest position, displacing a joining element (7) into a holding position between the holding ends (66) of the holding arms (S2), b. moving the punch (10) from the rest position in a joining direction R, wherein in the holding position, the joining element (7) is positioned upstream at a distance to the punch surface (16) of the working end (12) of the punch (10) (S3), c. placing the joining element (7) or the receiving sleeve (50) on a component (9) (S4), after that, d. displacing the punch (10) in the passage channel (52) relative to the receiving sleeve (50) and against the spring pre-tensioning between the punch (10) and the receiving sleeve (50) (S5), e. releasing the joining element (7) from the holding position between the holding ends (68) with the working end (12) of the punch (10) (S6) and joining the joining element (7) into the component (9) (S7).

10. The joining method according to claim 9, in which the joining element (7) is displaced into the holding position by means of an actuator (100).

11. The joining method according to claim 9 or 10 with the further step: delivering a new joining element (7) via an element delivery (94), in particular a profile hose, into a pre-position adjacent to the receiving nest (92), while the punch (10) or the adapter piston (30) blocks the receiving nest (92) (S1) or while the receiving nest (92) is freely accessible.

12. The joining method according to one of the claims 9 to 11 with the further step: moving the punch (10) from an operating position for joining the joining element (7) into the rest position, wherein the punch (10), supported by the spring pre-tensioning between the punch (10) and the receiving sleeve (50) is removed form-fit in a limited manner at least partly from the passage channel (52), preferably from an exit opening (54) of the passage channel (52) of the receiving sleeve (50) (S8).