# US 10,478,888 B2 · Method of fastening a rivet element and corresponding fastening system therefor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,478,888 B2 - Document ID: US10478888B2 - Status: Granted - Kind: B2 - Application number: 15/162,828 - Filed: 2016-05-24 - Published: 2017-01-12 - Granted: 2019-11-19 - Earliest claimed: 2015-06-11 - Assignees: Profil Verbindungstechnik GmbH & Co. KG - Applicants: PROFIL Verbindungstechnik GmbH & Co. KG - Inventors: Jiri Babej; Richard Humpert; Christian Sowa - Web page: https://patentgrep.com/patent/US10478888B2 ## CPC - B21J 15/04: Riveting hollow rivets mechanically - B21J 15/36: Rivet sets, i.e. tools for forming heads; Mandrels for expanding parts of hollow rivets - B23P 19/062: {Pierce nut setting machines} - B21J: FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES (rolling of metal B21B; making particular products by forging or pressing B21K; cladding or plating B23K; finishing surfaces by hammering B23P9/04; compacting surfaces by blasting with particulate material B24C1/10; general features of presses, presses for consolidating scrap B30B; furnaces in general F27) - B23P: METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS (arrangements for copying or controlling B23Q) ## Abstract A method of fastening a rivet element to a workpiece, which has a preshaped hole provided for a reception of a rivet section of the rivet element and which is made planar at least in the region around the preshaped hole. Prior to the fastening process, the workpiece is positioned at a well-defined spacing from a contact surface of a die by at least one movably and/or elastically configured spacer of the die for a reshaping of the rivet section, so that a gap is formed between a wall of the hole and a punch of the die, which is provided for the reshaping of the rivet section. The rivet section is introduced into the gap in a course of the fastening process and is reshaped by the punch in order to engage behind the workpiece in the region of the hole. ## Claims ### Claim 1 A method of fastening a rivet element (10) to a workpiece (12) which has a preshaped hole (26) provided for a reception of a rivet section (32) of the rivet element (10) and which is made planar at least in a region around the preshaped hole (26), wherein, prior to the fastening process, the workpiece (12) is positioned at a well-defined spacing (D) from a contact surface (18) of a die (14) by means of at least one movably and/or elastically configured spacer (16) of the die (14) for a reshaping of the rivet section (32), so that a gap (30) is formed between a wall (28) of the hole (26) and a punch (24) of the die (14), which is provided for the reshaping of the rivet section (32), the workpiece (12) only being moved toward the contact surface (18) after the start of the reshaping of the rivet section (32), and wherein the rivet section (32) is introduced into the gap (30) in a course of the fastening process and is reshaped by the punch (24) in order to engage behind the workpiece (12) in the region of the hole (26), wherein the spacer (16) is moved from a first position into a second position during the fastening process, the spacer (16) being substantially fully displaced into an inner region of the die (14) in the second position. ### Claim 2 (depends on 1) A method in accordance with claim 1, wherein the spacer (16) has a section (20) which projects out of the contact surface (18) of the die (14) prior to the fastening process, with the section (20) of the spacer (16) which projects out of the contact surface (18) defining the spacing (D). ### Claim 3 (depends on 1) A method in accordance with claim 1, wherein the workpiece is held at a defined spacing from the contact surface of the die by the spacer, and (12) is only moved toward the contact surface (18) after a completion of the reshaping of the rivet section (32). ### Claim 4 (depends on 1) A method in accordance with claim 1, wherein the workpiece (12) is moved toward the contact surface (18) by an abutment portion of the rivet element (10), in particular by a flange portion (36) of the rivet element (10) and/or by a setting head (46) which introduces the rivet element (10). ### Claim 5 (depends on 1) A method in accordance with claim 1, wherein the spacer (16) is preloaded into the first position by an associated preloading device (57) with a defined force. ### Claim 6 (depends on 5) A method in accordance with claim 5, wherein the spacer (16) is moved from the first position during the fastening process when the workpiece (12) is moved toward the contact surface (18). ### Claim 7 (depends on 1) A method in accordance with claim 1, wherein the spacer (16) adopts a first position due to elastic properties of the spacer (16), with the spacer (16) defining the spacing (D) in the first position. ### Claim 8 (depends on 7) A method in accordance with claim 7, wherein the shape of the spacer (16) is changed when the workpiece (12) is moved toward the contact surface (18). ### Claim 9 (depends on 7) A method in accordance with claim 7, wherein the shape of the spacer (16) is changed during the fastening process, in particular with the spacer (16) being substantially fully displaced into an inner region of the die (14) in the second position. ### Claim 10 (depends on 1) A method in accordance with claim 1, wherein the workpiece (12) is pressed, at least in the region of the rivet section (32) engaging behind the workpiece (12), into a receiving recess of the rivet element. ### Claim 11 (depends on 10) A method in accordance with claim 10, wherein the receiving recess into which the workpiece (12) is pressed is a groove (38), which is formed at a flange portion (36) of the rivet element. ### Claim 12 (depends on 1) A method in accordance with claim 1, wherein the workpiece is a sheet metal part. ### Claim 13 (depends on 1) A fastening system for fastening a rivet element (10) to a workpiece (12), in particular in accordance with a method in accordance with claim 1, wherein the workpiece (12) has a preshaped hole (26) provided for the reception of a rivet section (32) of the rivet element (10) and is made planar at least in the region around the preshaped hole (26), wherein the fastening system includes a die (14) in order to position the workpiece (12) at a well-defined spacing (D) from a contact surface (18) of the die (14) during the fastening process so that a gap (30) is formed between a wall (28) of the hole (26) and the punch (24) of the die (14), wherein the fastening system furthermore includes a setting head (46) in which the rivet element (10) is receivable at least in part. ### Claim 14 (depends on 13) A fastening system in accordance with claim 13, wherein the setting head (46) has a workpiece contact surface (50) which lies in a plane with a workpiece contact surface (37) of the rivet element (10) when the rivet element (10) is received in the setting head (46).