# US 2022/0034048 A1 · Switching assembly for an electric screed heating device of a road paver > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0034048 A1 - Document ID: US20220034048A1 - Status: Published application - Kind: A1 - Application number: 17/388,496 - Filed: 2021-07-29 - Published: 2022-02-03 - Earliest claimed: 2020-07-29 - Assignees: Joseph Voegele AG - Applicants: Joseph Voegele AG - Inventors: Michael HEINDTEL; Achim EUL - Web page: https://patentgrep.com/patent/US20220034048A1 ## CPC - E01C 19/48: for laying-down the materials and consolidating them, or finishing the surface {, e.g. slip forms therefor, forming kerbs or gutters in a continuous operation in situ (E01C19/002, E01C23/065 take precedence; devices for guiding or controlling the machines along a predetermined path E01C19/004)} - E01C 19/4873: {Apparatus designed for railless operation} - E01C 2301/10: Heated screeds - E01C: CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR (forming roads or like surfaces by compacting or grading snow or ice E01H) ## Abstract A road paver comprises a tractor vehicle with a material hopper for receiving paving material and a paving screed for compacting paving material. The paving screed comprises at least one electric heating device for heating the paving screed. The road paver comprises at least one electric switching assembly configured to switch an electric power supply of the electric heating device. The electric switching assembly comprises an electric parallel circuit of two switching devices, wherein the electric parallel circuit of the two switching devices forms a series electric circuit with the electric heating device. ## Claims ### Claim 1 A road paver, comprising: a tractor vehicle with a material hopper for receiving paving material; a paving screed for compacting paving material, wherein the paving screed comprises an electric heating device for heating the paving screed; and an electric switching assembly configured to switch an electric power supply of the electric heating device, wherein the electric switching assembly comprises an electric parallel circuit of two switching devices, and wherein the electric parallel circuit of the two switching devices forms an electric series circuit with the electric heating device. ### Claim 2 (depends on 1) The road paver according to claim 1, wherein the two switching devices are configured to alternately supply electric power to the electric heating device. ### Claim 3 (depends on 1) The road paver according to claim 1, wherein the two switching devices are connected to a common input of the electric heating device. ### Claim 4 (depends on 1) The road paver according to claim 1, wherein the electric switching assembly is provided on the paving screed. ### Claim 5 (depends on 1) The road paver according to claim 1, wherein the two switching devices are semiconductor switching devices. ### Claim 6 (depends on 1) The road paver according to claim 1, wherein the two switching devices each comprise a transistor, a thyristor or a bidirectional thyristor diode. ### Claim 7 (depends on 1) The road paver according to claim 1, wherein the electric switching assembly is configured to supply an AC voltage to the electric heating device. ### Claim 8 (depends on 7) The road paver according to claim 7, wherein each switching device is configured to let at least one complete sine wave of the AC voltage pass in one go. ### Claim 9 (depends on 7) The road paver according to claim 7, wherein the two switching devices are configured to let successive sine waves of the AC voltage pass in an alternating manner. ### Claim 10 (depends on 1) The road paver according to claim 1, wherein the electric heating device is a resistance heating element. ### Claim 11 A method for heating a paving screed of a road paver, comprising: supplying electric power to an electric resistance heating element provided on the paving screed; wherein an electric power supply to the electric resistance heating element is switched with an electric switching assembly, and wherein two switching devices of the electric switching assembly alternately supply the electric resistance heating element with electric power. ### Claim 12 (depends on 11) The method according to claim 11, wherein the electric resistance heating element is supplied with an AC voltage, and wherein a frequency of switching the supply to the electric resistance heating element between the two switching devices corresponds to a frequency of the AC voltage. ### Claim 13 (depends on 11) The method according to claim 11, wherein the electric resistance heating element is continuously supplied with electric power during the alternating power supply by the two electric switching devices. ### Claim 14 A method for heating a paving screed of a road paver, the method comprising using two alternately switched switching devices in an electric switching assembly for supplying electric power to an electric heating device on the paving screed of the road paver to reduce a risk of overheating of the electric switching assembly.