Method and apparatus for feeding joining elements

Abstract

A method and apparatus for feeding joining elements to a joining tool is presented. The joining tool may be movable by a programmable handling unit, and a magazine for receiving at least one joining element may be mounted on the joining tool. The magazine may be moved to a filling station that has a tubular section with an outlet opening. An inlet opening of the magazine may be oriented in relation to the outlet opening. At least one joining element may be conveyed to the tubular section so that it passes through the tubular section, the outlet opening, the inlet opening, and into the magazine. During the orienting, the magazine may be oriented in relation to the outlet opening such that the magazine is spaced apart from the filling station during the conveying of the at least one joining element.

Claims

1. An apparatus for feeding joining elements, comprising: a joining tool that is movable by a programmable handling unit, the joining tool configured to perform a joining connection between two workpieces using at least one joining element; a magazine mounted on the joining tool and adapted to receive the at least one joining element, the magazine having an inlet opening; a filling station having a tubular section with an outlet opening, the tubular section adapted to feed the at least one joining element to the magazine so that, when the at least one joining element is being conveyed from the filling station into the magazine, the inlet opening of the magazine first receives the at least one joining element after the at least one joining element exits the filling station through the outlet opening, wherein the apparatus is adapted to convey the at least one joining element from the filling station into the magazine when the inlet opening of the magazine is aligned with the outlet opening of the filling station, and a control device that is programmed to control a relative position of the magazine and the filling station so that the magazine is spaced apart from the filling station when the at least one joining element is being conveyed from the filling station into the magazine, wherein the magazine has an insertion section between the inlet opening and a receiving section of the magazine, the insertion section widening from the receiving section towards the inlet opening such that the joining element is centered during entry into the magazine.

2. The apparatus of claim 1, wherein the filling station has a centering aid that is arranged concentrically around the outlet opening.

3. The apparatus of claim 2, wherein the centering aid has a centering cage that comprises a plurality of webs that are adapted to be deflectable radially and together form a conical shape.

4. The apparatus of claim 3, wherein the centering aid is formed concentrically around the outlet opening to taper conically in the outlet direction, wherein a diameter of a free end of the centering aid and a diameter of the inlet opening are adapted to allow the centering aid to dip at least partially into the insertion section.

5. The apparatus of claim 1, wherein a laterally open radial guide section is arranged in the region of the inlet opening or in the region of the outlet opening, wherein the radial guide section of the tubular section of the filling station or a tubular section of the magazine can be inserted into the region of the inlet of the opening or the region of the outlet opening in a direction transverse with respect to a conveying direction, in order to center the magazine in relation to the filling station.

6. The apparatus of claim 1, wherein the at least one joining element is a rivet or a stud.

7. The apparatus of claim 1, wherein the tubular section is a permanent continuously open tubular section so that the outlet opening is unblocked before aligning the inlet opening of the magazine with the outlet opening and after conveying the at least one joining element to the magazine.

8. The apparatus of claim 1, further comprising a sensor arrangement to detect whether the magazine has approached the outlet opening of the filling station.

9. An apparatus for feeding joining elements, comprising: a joining tool that is movable by a programmable handling unit, the joining tool configured to perform a joining connection between two workpieces using at least one joining element; a magazine mounted on the joining tool and adapted to receive the at least one joining element, the magazine having an inlet opening; a filling station having a tubular section with an outlet opening, the tubular section adapted to feed the at least one joining element to the magazine, and a control device that is programmed to control a relative position of the magazine and the filling station so that the magazine is spaced apart from the filling station and the inlet opening of the magazine is aliened with the outlet opening of the filling station when the at least one joining element is being conveyed from the filling station into the magazine, wherein the magazine has an insertion section between the inlet opening and a receiving section of the magazine, the insertion section widening from the receiving section towards the inlet opening such that the joining element is centered during entry into the magazine.

10. The apparatus of claim 9, wherein the filling station has a centering aid that is arranged concentrically around the outlet opening.

11. The apparatus of claim 9, wherein the at least one joining element is a rivet or a stud.

12. The apparatus of claim 9, wherein the tubular section is a permanent continuously open tubular section so that the outlet opening is unblocked before aligning the inlet opening of the magazine with the outlet opening and after conveying the at least one joining element to the magazine.

13. The apparatus of claim 9, further comprising a sensor arrangement to detect whether the magazine has approached the outlet opening of the filling station.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows a diagrammatic illustration of one embodiment of a joining assembly.

(2) FIG. 2 shows a view of an embodiment of a joining assembly.

(3) FIG. 3 shows a view of an embodiment of a joining assembly.

(4) FIG. 4 shows a view of an embodiment of a joining assembly.

(5) FIG. 5 shows a plan view of the magazine arrangement of FIG. 4.

DETAILED DESCRIPTION

(6) Referring now more particularly to the drawings, FIG. 1 illustrates one embodiment of a joining assembly 10 for producing joined connections by means of joining elements. In the present case, the joining assembly 10 is configured, in particular, for punch riveting. In a corresponding way, however, the joining assembly 10 can also be configured, for example, for producing stud joined connections (stud welding, stud adhesion, etc.).

(7) The joining assembly 10 has a joining head 12 which is connected to a programmable handling unit in the form of a robot 14. In more precise terms, the robot 14 has, for example, a first arm 16 and a second arm 18, the joining head 12 being fixed on the second arm 18.

(8) A joining tool 20 in the form of a punch riveting tool is fixed on the joining head 12. The joining tool 20 contains a C-frame 22. A ram 24 of the joining tool 20, which ram 24 can be moved in a joining direction, is mounted at an upper end of the C-frame 22. A die 26 is fixed at the other end of the C-frame 22.

(9) The joining tool 20 is designed for carrying out joined connections by means of joining elements 28. In the present case, the joining elements 28 are punch rivet elements, in particular hollow punch rivet elements.

(10) For example, two or more workpieces (for example in the form of metal sheets made from identical or different materials) can be inserted between the ram 24 and the die 26. These workpieces are subsequently connected by the fact that a punch rivet element is pressed into the workpiece arrangement by means of the ram 24. In the case of a hollow punch rivet, an originally substantially cylindrical hollow section is spread radially, with the result that an undercut is carried out within the workpiece arrangement.

(11) The movement of the ram 24 generally takes place along a joining axis 30.

(12) A magazine arrangement 32 is fixed on the joining tool 20 or the joining head 12. The magazine arrangement 32 has a magazine section or receiving section 34 for receiving at least one, preferably a plurality of joining elements 28.

(13) Furthermore, the magazine arrangement 32 has an inlet opening 36 which is formed concentrically with respect to the magazine section 34 and has a diameter D1. The inlet opening 36 is connected to the magazine section 34 via an insertion section 38. The insertion section 38 widens from the magazine section 34 towards the inlet opening 36. In particular, the insertion section 38 is of conical configuration.

(14) Furthermore, the magazine arrangement 32 has a magazine plate which preferably extends in a direction transverse with respect to the joining axis 30 and is preferably connected fixedly to the magazine section 34. A gas closure 40 which can be actuated by means of a gas-closure actuator is provided in the region of the magazine plate. The gas-closure actuator can move the gas closure 40 out of a closed position into an open position, in which joining elements 28 can be fed into the magazine section 34.

(15) Furthermore, the joining assembly 10 has a filling station 46. The filling station 46 has a tubular section 48 which comprises an outlet opening 50. Furthermore, the filling station 46 has a filling-station plate 52, on which the tubular section 48 is fixed, in such a way that the outlet opening 50 is aligned substantially flush with a surface (not denoted in greater detail) of the filling-station plate 52. In an alternative, particularly preferred embodiment, the tubular section 48 can also protrude with respect to the surface of the filling-station plate 52, as is described in some following embodiments. The filling-station plate 52 is arranged in a stationary manner by means of a carrier 55 in the region of the operating range of the handling unit 14.

(16) Furthermore, the tubular section 48 has a feed opening 56. Here, the tubular section 48 is configured in such a way that it is always continuous between the feed opening 56 and the outlet opening 50. In other words, no locking bolts or the like which could impede or block the passage through the tubular section 48 are provided in the region of the filling station 46.

(17) Furthermore, a sensor arrangement 58 is fixed on the filling station 46, in particular on the filling-station plate 52. The sensor arrangement 58 can detect whether the magazine section 34 has approached the filling station 46. The sensor arrangement 58 can preferably detect if the magazine section 34 is oriented in relation to the filling station 46 in such a way that joining elements 28 can be transferred through the filling station into the magazine arrangement. In the aligned position, in particular, an inlet opening (not denoted in greater detail) of the magazine section 34 and the outlet opening 50 of the tubular section 48 are aligned with one another. The sensor arrangement can be a simple sensor arrangement, for example in the form of an optical, a magnetic or an electric sensor. In the simplest case, it can also be an electric contact or switch. It is preferred in some embodiments that at least two individual sensors detect the approach of the magazine to the filling station, in order to achieve a certain redundancy. In order to detect the orientation, it can likewise be appropriate to use a plurality of sensors.

(18) The feed opening 56 of the tubular section 48 is connected to a feed hose 62 of a feed device 60. The feed device 60 comprises a stationary supply container 64 for receiving a multiplicity of joining elements 28. Furthermore, the feed device 60 comprises a separating device 66, in which the joining elements are separated. Finally, the feed device 60 comprises a conveying device, in particular in the form of a compressed-air assembly 68. Joining elements 28 can be conveyed through the feed hose 62 to the filling station 52 by means of the compressed-air assembly 68, as shown diagrammatically in FIG. 1. It is possible here to first of all convey conveying elements individually by the compressed-air assembly 68 into an intermediate position, to be precise preferably whenever a joining element has been joined by means of the joining tool 20. As soon as the magazine section 34 is empty, the quantity of joining elements 28 made available in the meantime can be fed through the filling station 46 into the magazine section 34 in one step immediately one after another without stopping.

(19) Furthermore, the joining assembly 10 comprises a control device 70. The control device 70 is designed for controlling various individual processes and individual units of the joining assembly 10. Furthermore, the control device 70 also optionally serves to supply energy. It is shown, for example, that the control device 70 is connected to the sensor arrangement 58. Furthermore, the control device 70 is designed for actuating the gas-closure actuator 40. Furthermore, the control device 70 is preferably likewise designed for controlling the robot 14 according to a defined program. Furthermore, the control device 70 is also connected to the joining tool 20 and is designed, for example, for actuating the ram 24. Here, the control device 70 can be connected via a cable arrangement to the robot 14 and/or to the joining head 12. Furthermore, the control device 70 can be connected to the filling station 46 via a cable arrangement, in particular in the form of an individual sensor cable.

(20) The joining assembly 10 is preferably operated as follows. Here, a state is assumed, in which a plurality of joining elements 28 are received in the magazine section 34. Here, the robot 14 moves the joining head 12 to a joining position, in which workpieces to be connected to one another are arranged between the ram 24 and the die 26. Subsequently, a joining element 28 is removed from the magazine section 34, as is indicated diagrammatically in FIG. 1 by an arrow. This removal can be carried out manually, but can preferably take place by means of a loading device which is actuated, for example, by means of the control device 70.

(21) First of all, the ram 24 is moved, in order to carry out the actual joining process. Subsequently, the ram 24 moves back into its initial position, and the joining head 12 is moved to a next joining position, etc. As soon as there are no or only a small number of joining elements 28 in the magazine section 34, the joining head 12 is moved to the filling station 46. Here, the number of joining elements 28b situated in the magazine section 34 can be monitored by a sensor arrangement. However, it is preferred if the number of joining elements 28 in the magazine section 34 is always known by a controller which counts along in the control device 70.

(22) As soon as the magazine plate 36 has approached the filling-station plate 52 and the outlet opening 50 is aligned with an inlet opening 36 of the magazine section 34, the gas-closure actuator 40 is actuated, in order to open the gas closure 40. Subsequently, a joining element 28 or a plurality of joining elements 28 is/are conveyed via the compressed-air assembly 68 unimpeded from the separating device 66 (or from a buffer store) into the magazine section 34, that is to say through the feed hose 62 and the tubular section 48 in an unimpeded manner.

(23) As soon as the magazine section 34 is filled again, the gas closure is closed again by means of the gas-closure actuator, in order to achieve a gas closing-off which is sufficient for it to be possible to transport joining elements further by means of compressed gas.

(24) Subsequently, the joining head 12 moves away from the filling station 46 and again carries out further joining operations.

(25) The following figures show other embodiments of joining assemblies or feed devices and magazine arrangements which generally correspond to the corresponding elements of the joining assembly 10 of FIG. 1 with regard to structure and method of operation. Identical elements are therefore denoted by identical reference numerals.

(26) The embodiment shown in FIG. 2 of a joining assembly 10 comprises a filling station 46, in which the tubular section 48 protrudes with respect to an underside of the filling-station plate 52. A centering aid 74 in the form of a centering cage 76 is fixed on the filling-station plate 52 concentrically with respect to this protruding part of the tubular section 48. The centering cage 76 has a plurality of webs 78 which can be deflected radially and jointly enclose a conical shape. In the radially non-extended state, the external diameter of the free end of the centering cage 76 is smaller than the diameter of the inlet opening 36. Furthermore, the internal diameter of the free end of the centering cage 76 is smaller than the internal diameter of the tubular section 48.

(27) FIG. 2 shows here that the free end of the centering cage 76 dips into the insertion section 38 without making contact with it.

(28) When joining elements are fed through the tubular section 48, they exit out of the outlet opening 50. Here, the outlet opening 50 is spaced apart from the inlet opening 36 of the magazine arrangement 32. During this free flight phase, the joining elements pass from the inside against the webs 78 of the centering cage 76 and deflect the said webs 78 radially to the outside, as a result of which they are centered in their free flight phase until they pass into the insertion section 38.

(29) Furthermore, loss of joining elements between the outlet opening 50 and the inlet opening 36 can be prevented in this embodiment.

(30) Furthermore, the centering cage 76 can be used as an orientation aid during teaching of the alignment position. Furthermore, slightly inaccurate positioning in the alignment position can be accepted as a result of the centering action by means of the centering cage 76.

(31) FIG. 3 shows a further embodiment of a joining assembly 10. In this, the tubular section 48 once again protrudes with respect to the underside of the filling-station plate 52. In the alignment position shown in FIG. 3, the free end of the tubular section is positioned with the outlet opening 50 directly above the inlet opening. Here, the diameter of the inlet opening 36 is preferably at least somewhat greater than the external diameter of the tubular section 48.

(32) Here, the tubular section 48 and the magazine arrangement 32 preferably do not make contact with one another, but can do so. It is preferred in this embodiment if the handling unit 14 is programmed by means of a positioning aid.

(33) FIGS. 4 and 5 show a further embodiment of a joining assembly 10. In this embodiment, the magazine arrangement 32 has a radial guide section 80 above the insertion section 38, which radial guide section 80 is shown in plan view in FIG. 5. The radial guide section 80 comprises a receptacle 82 which is U-shaped in plan view and into which a protruding part of the tubular section 48 can be inserted in an insertion direction 84.

(34) Here, the U-shaped receptacle 82 can be moved closer via a funnel section. In this embodiment, the tubular section 48 is preferably formed by a slightly flexible hose section of a feed hose. Inaccuracies during teaching of the handling unit 14 can be compensated for by the radial guide section 80.

(35) The radial guide section 80, which is laterally open, may comprise a U-shaped or a V-shaped receptacle 82.

(36) While the principles of the invention have been made clear in the illustrative embodiments set forth above, it will be apparent to those skilled in the art that various modifications may be made to the structure, arrangement, proportion, elements, materials, and components used in the practice of the invention.

(37) It will thus be seen that the objects of this invention have been fully and effectively accomplished. It will be realized, however, that the foregoing preferred specific embodiments have been shown and described for the purpose of illustrating the functional and structural principles of this invention and are subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.