# US 11,121,599 B2 · Slot sealing compound, slot seal, and method for producing a slot seal > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,121,599 B2 - Document ID: US11121599B2 - Status: Granted - Kind: B2 - Application number: 15/036,653 - Filed: 2014-11-06 - Published: 2016-09-29 - Granted: 2021-09-14 - Earliest claimed: 2013-11-14 - Assignees: Siemens Aktiengesellschaft - Applicants: Siemens Aktiengesellschaft - Inventors: Jürgen Huber; Bernhard Klaussner; Dieter Schirm - Web page: https://patentgrep.com/patent/US11121599B2 ## CPC - H02K 3/493: magnetic - H01B 3/40: epoxy resins - H02K 3/30: Windings characterised by the insulating material - H02K 15/13: Applying slot closure means in the cores; Manufacture of slot closure means - B29C 35/0805: {using electromagnetic radiation} - B29C 2035/0827: {using UV radiation} - B29K 2063/00: Use of {EP, i.e.} epoxy resins {or derivatives thereof}, as moulding material - B29K 2105/16: Fillers - B29K 2105/162: {Nanoparticles} - B29K 2505/12: Iron - B29K 2995/0008: Magnetic or paramagnetic - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - H01B: CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES (selection for magnetic properties H01F1/00; waveguides H01P {; printed circuits H05K}) - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS ## Abstract The invention relates to a slot sealing compound (7) for an electrical machine that comprises at least one slot (2) with a slot opening (5) for receiving an electrical conductor arrangement (3). Said slot sealing compound (7) contains a magnetic filler material, particularly a soft-magnetic filler material, and a reactive resin mixture that comprises at least one resin component. In the interests of improving storage stability for said slot sealing compound (7), the components thereof are selected to be suitable for cationic polymerisation. A catalyst, provided to accelerate the cationic polymerisation of said reactive resin mixture, is also added to said slot sealing compound (7). ## Claims ### Claim 1 A slot sealing compound for filling into a slot opening of an electric machine that accommodates an electric conductor arrangement for the electric machine, comprising: a reactive resin mixture containing at least one resin component; a catalyst configured to accelerate a cationic polymerization of the reactive resin mixture; a magnetic filler material; and an additive configured to bind or inhibit the catalyst at a temperature of up to 45° C. so as to prevent the catalyst from accelerating the cationic polymerization of the reactive resin mixture and thereby render the slot sealing compound storage stable up to a temperature of 45° C., said additive is selected from the group consisting of aluminum trihydrate, magnesium hydroxide and their salts. ### Claim 2 (depends on 1) The slot sealing compound of claim 1, wherein the magnetic filler material is a soft-magnetic filler material. ### Claim 3 (depends on 1) The slot sealing compound of claim 1, wherein the catalyst is at least one substance selected from the group consisting of organic ammonium salt, sulphonium salt, phosphonium salt, and imidazolium salt. ### Claim 4 (depends on 1) The slot sealing compound of claim 1, wherein the catalyst has a percentage by weight of at most 5% by weight. ### Claim 5 (depends on 1) The slot sealing compound of claim 1, wherein the catalyst has a percentage by weight of at most 1% by weight of the reactive resin mixture. ### Claim 6 (depends on 1) The slot sealing compound of claim 1, wherein the resin component is an epoxy resin. ### Claim 7 (depends on 1) The slot sealing compound of claim 1, further comprising organic and/or inorganic nanoparticles. ### Claim 8 (depends on 1) The slot sealing compound of claim 1, having a glass transition temperature of at least 180° C. ### Claim 9 (depends on 1) The slot sealing compound of claim 1, wherein the magnetic filler material has a percentage by weight, which amounts to at least 85% by weight. ### Claim 10 (depends on 1) The slot sealing compound of claim 1, wherein the magnetic filler material is present in the form of bimodal to multimodal particle size distributions. ### Claim 11 (depends on 1) The slot sealing compound of claim 1, having a storage stability of several days at a temperature of up to 45° and/or an air humidity of more than 50%. ### Claim 12 (depends on 1) A slot seal, comprising the slot sealing compound of claim 1. ### Claim 13 A method for producing a slot seal in an electric machine, comprising, mixing a reactive resin mixture, comprising at least one resin component together with a magnetic filler material and a catalyst to accelerate a cationic polymerization of the reactive resin mixture and an additive selected from the group consisting of aluminum trihydrate, magnesium hydroxide and their salts to form a slot sealing compound as a slot seal for an electric machine, the slot sealing compound being storage stable up to a temperature of 45° C., introducing a conductor arrangement into a slot of the electric machine, placing the slot sealing compound to seal a seal opening of the slot; and thereafter subjecting the slot sealing compound to a heat treatment initiating the cationic polymerization of the slot sealing compound. ### Claim 14 (depends on 13) The method of claim 13, further comprising hardening initially only a surface of the slot sealing compound through heat treatment to realize a superficial hardening. ### Claim 15 (depends on 13) The method of claim 13, further comprising hardening initially only a surface of the slot sealing compound through UV treatment to realize a superficial hardening. ### Claim 16 (depends on 13) The method of claim 13, wherein the polymerization of the slot sealing compound takes place at a hardening temperature from about 70° C.