# US 2021/0276508 A1 · Gas generator having a pyrotechnic propelling charge and method for producing the propelling charge > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0276508 A1 - Document ID: US20210276508A1 - Status: Published application - Kind: A1 - Application number: 16/319,573 - Filed: 2017-07-21 - Published: 2021-09-09 - Earliest claimed: 2016-07-26 - Assignees: TRW Airbag Systems GmbH - Applicants: TRW Airbag Systems GmbH - Inventors: Friedrich Jorg; Siegfried Jahnel - Web page: https://patentgrep.com/patent/US20210276508A1 ## CPC - B60R 21/2644: {using only solid reacting substances, e.g. pellets, powder} - B60R: VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR ## Abstract A gas generator for use for a safety device in vehicles comprises a pyrotechnical propelling charge, wherein the propelling charge is formed from a first and at least a second master batch which are in a mixed state in a filling. Each master batch has a plurality of molded propellant bodies having defined geometry and having a relative quickness. The relative quickness RQ2 of the second master batch is less than the relative quickness RQ1 of the first master batch, wherein RQ2=RQ1·fq and fq≤0.9. The invention further relates to a method for producing the propelling charge. ## Claims ### Claim at position 1 1-17. (canceled) ### Claim 18 A gas generator comprising a pyrotechnical propelling charge, wherein the propelling charge is formed from a first and at least a second master batch which are in a mixed state in a filling, each master batch having a plurality of molded propellant bodies having defined geometry and having a relative quickness, wherein the relative quickness RQ2 of the second master batch is less than the relative quickness RQ1 of the first master batch, wherein RQ2=RQ1·fq and fq≤0.9. ### Claim 19 (depends on 18) The gas generator according to claim 18, wherein the molded propellant bodies in the first and second master batches as well as optionally in each further master batch have the same composition. ### Claim 20 (depends on 18) The gas generator according to claim 18, wherein the geometry of the molded propellant bodies in the first master batch is equal but is different from the geometry of the molded propellant bodies in the second master batch. ### Claim 21 (depends on 18) The gas generator according to claim 18, wherein the molded propellant bodies are present in the form of propellant pellets. ### Claim 22 (depends on 21) The gas generator according to claim 21, wherein the propellant pellets in the first and second as well as optionally any further master batches have the same diameter but different height. ### Claim 23 (depends on 22) The gas generator according to claim 22, wherein the diameter is within a range of from 2 mm to 10 mm. ### Claim 24 (depends on 18) The gas generator according to claim 18, wherein the fq is within a range of from 0.4 to 0.9. ### Claim 25 (depends on 18) The gas generator according to claim 18, wherein the propelling charge is formed from more than two master batches, with RQx denoting the relative quickness of one single master batch and being larger than the relative quickness RQx+1 of the next master batch, wherein RQx≥RQx+1·0.9. ### Claim 26 (depends on 25) The gas generator according to claim 25, wherein the propelling charge is formed from three master batches, with RQ1 denoting the relative quickness of the first master batch, RQ2 denoting the relative quickness of the second master batch and RQ3 denoting the relative quickness of the third master batch, wherein RQ1>RQ2>RQ3 and RQ1 RQ2≥0.9 as well as RQ2≥RQ3·0.9. ### Claim 27 (depends on 18) The gas generator according to claim 18, wherein the first master batch shows a time until reaching the maximum can pressure tpKmax(1) measured in a can test and the second master batch shows a time until reaching the maximum can pressure tpKmax(2) measured in equal test conditions in the can test, wherein tpKmax(1)·ft=tpKmax(2), wherein ft is within a range of from 1.35 to 3.2. ### Claim 28 A method for producing a pyrotechnical propelling charge for use in a gas generator comprising the following steps of: providing a first master batch consisting of a plurality of molded propellant bodies having predefined geometry and a first relative quickness RQ1; providing a second master batch consisting of a plurality of molded propellant bodies having predefined geometry and a second relative quickness RQ2, the relative quickness RQ2 of the second master batch being less than the relative quickness RQ1 of the first master batch, wherein RQ2=RQ1·fq and fq≤0.9; and mixing a predetermined amount of the first master batch with a predetermined amount of the second master batch while forming the pyrotechnical propelling charge in the form of a filling in which the molded propellant bodies are present in a mixed state. ### Claim 29 (depends on 28) The method according to claim 28, wherein the molded propellant bodies are in a homogenously mixed state in the filling. ### Claim 30 (depends on 28) The method according to claim 28, wherein at least one further master batch consisting of pyrotechnical propellant comprising a plurality of molded propellant bodies having predefined geometry and a relative quickness RQ3 is provided, the geometry of the molded propellant bodies in the further master batch being different from the geometry of the molded propellant bodies in the first and second master batches and the relative quickness RQ3 of the further master batch being less than the relative quickness RQ2 of the second master batch, wherein RQ3=RQ2·fq and fq≤0.9. ### Claim 31 (depends on 18) The method according to claim 18, wherein the geometry of the molded propellant bodies within one single master batch is equal but is different from the geometry of the molded propellant bodies within the respective other master batches. ### Claim 32 (depends on 28) The method according to claim 28, wherein a ballistic property of the pyrotechnical propelling charge is defined and the predetermined amount of the first master batch and of the second master batch is set so that the filling of the molded propellant bodies exhibits the ballistic property. ### Claim 33 (depends on 28) The method according to claim 28, wherein the ballistic property is selected from the group consisting of the relative quickness RQ, the maximum chamber pressure in a standard combustion chamber pBKmax, the maximum can pressure in a can test pKmax, the time until reaching the maximum chamber pressure in the standard combustion chamber tpBKmax, the time until reaching the maximum can pressure in the can test tpKmax, the maximum combustion chamber pressure of a gas generator pBKGGmax, the time until reaching the maximum combustion chamber pressure in the gas generator tpBKGGmax, the burn-off rate and/or the burn-off duration. ### Claim 34 (depends on 28) The method according to claim 28, wherein the mixing of the master batches is carried out directly at a production line of the gas generator.