# US 2018/0022035 A1 · Limiting dispersion of ir radiation from a heater element during plastic welding > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0022035 A1 - Document ID: US20180022035A1 - Status: Published application - Kind: A1 - Application number: 15/639,818 - Filed: 2017-06-30 - Published: 2018-01-25 - Earliest claimed: 2016-07-25 - Assignees: SPM Automation (Canada) Inc. - Applicants: Spm Automation (Canada) Inc. - Inventors: Rade Pupovac; Zachary Touesnard; Christian Peter Holtkamp; Boris Novakovic - Web page: https://patentgrep.com/patent/US20180022035A1 ## CPC - B29C 65/1412: {Infrared [IR] radiation} - B29C 65/1432: {direct heating of the surfaces to be joined} - B29C 65/1487: {making use of light guides (B29C65/1687 takes precedence)} - B29C 65/1496: {making use of masks (B29C65/1696 takes precedence)} - B29C 65/20: with direct contact, e.g. using "mirror" - B29C 65/30: Electrical means {(B29C65/38 takes precedence)} - B29C 65/305: {involving the use of cartridge heaters} - B29C 66/003: {Protecting areas of the parts to be joined from overheating (B29C66/348, B29C66/8744 take precedence)} - B29C 66/242: {said joint lines being closed, i.e. forming closed contours} - B29C 66/244: {said joint lines being non-straight, e.g. forming non-closed contours} - B29C 66/301: {Three-dimensional joints, i.e. the joined area being substantially non-flat (B29C66/5223, B29C66/5224, B29C66/5225 take precedence)} - B29C 66/348: {Avoiding melting or weakening of the zone directly next to the joint area, e.g. by cooling} - B29C 66/54: {Joining several hollow-preforms, e.g. half-shells, to form hollow articles, e.g. for making balls, containers; Joining several hollow-preforms, e.g. half-cylinders, to form tubular articles} - B29C 66/73921: {characterised by the materials of both parts being thermoplastics} - B29C 66/81831: {of the welding jaws} - B29C 66/8167: {Quick change joining tools or surfaces} - 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) ## Abstract In a process for welding plastic parts together, an IR shield redirects IR radiation emitted from a heater of a heating tool so that IR radiation which would otherwise be directly incident on certain portions of a plastic part and/or on other parts of the heating tool is avoided. ## Claims ### Claim 1 A heating tool for performing an operation on a plastic part to melt plastic at a location where a weld joint is to be created, the heating tool comprising: a) a thermally conductive body having a base, a top, and a side which joins the top and the base, the top having a shape conforming to that of plastic to be melted for creating a weld joint in a plastic part; b) a heater for heating the thermally conductive body to create a temperature at the top for enabling the top to melt plastic; c) an IR shield confronting at least a portion of the side of the thermally conductive body without obstructing the top of the body, the shield comprising an inner first layer having an inner face facing the side for reflecting incident heat radiated from the body back toward the body and an outer face disposed against an inner face of an outer second layer, material of the inner first layer having lower emissivity than material of the second outer layer. ### Claim 2 (depends on 1) The heating tool as set forth in claim 1 in which the side of the thermally conductive body comprises opposite sides each of which joins the top and the base, and the shield comprises a first side which confronts a first of the opposite sides of the body and a second side which confronts a second of the opposite sides of the body, and in which the first side and the second side of the shield cooperatively define an opening which leaves the top of the body unobstructed by the shield. ### Claim 3 (depends on 2) The heating tool as set forth in claim 2 in which the top comprises a ridge. ### Claim 4 (depends on 3) The heating tool as set forth in claim 3 in which the ridge protrudes through the opening beyond the first side and the second side of the shield. ### Claim 5 (depends on 4) The heating tool as set forth in claim 4 further comprising a tooling plate and a support structure which supports the body on the tooling plate. ### Claim 6 (depends on 5) The heating tool as set forth in claim 5 in which the first side of the shield is fastened to the support structure and has an edge which confronts the ridge, and the second side of the shield is fastened to the support structure and which has an edge which confronts the ridge, and in which the edge of the first side of the shield and the edge of the second side of the shield cooperatively define the opening. ### Claim 7 (depends on 6) The heating tool as set forth in claim 6 in which the first side of the shield comprise slits extending from the edge of the first side of the shield, and the second side of the shield comprise slits extending from the edge of the second side of the shield. ### Claim 8 (depends on 5) The heating tool as set forth in claim 5 in which the ridge has a length and an elevation which as measured to the tooling plate varies along that length, and at least one of the sides of the shield comprises multiple individual shield parts fastened to the support structure. ### Claim 9 (depends on 8) The heating tool as set forth in claim 8 in which at least some of the individual shield parts comprise slits and bends for conforming the shield to varying elevation of the ridge along the length of the ridge. ### Claim 10 (depends on 9) The heating tool as set forth in claim 9 in which both of the sides of the shield comprise multiple individual shield parts. ### Claim 11 (depends on 9) The heating tool as set forth in claim 9 in which at least some of the slits extend from edges of individual shield parts which confront the ridge. ### Claim 12 (depends on 1) The heating tool as set forth in claim 1 in which the thermally conductive body comprises a channel within which the heater is disposed. ### Claim 13 (depends on 12) The heating tool as set forth in claim 12 in which the heater comprises an electric heater. ### Claim 14 (depends on 1) The heating tool as set forth in claim 1 in which the inner first layer has an emissivity no greater than 0.3. ### Claim 15 (depends on 14) The heating tool as set forth in claim 14 in which the IR shield comprises aluminized steel. ### Claim 16 A heating tool for melting a surface portion of a plastic part at a location where a weld joint is to be created during a plastic welding process, the heating tool comprising: a) a heater having a shape for melting a surface portion of a plastic part at a location where a weld joint is to be created and for emitting IR radiation in a direction beyond the surface portion where a weld joint is to be created; and b) an IR shield comprising a reflecting face having an emissivity no greater than 0.3 for redirecting IR radiation emitted by the heater in a direction beyond the surface portion where a weld joint is to be created in a different direction. ### Claim 17 (depends on 16) The heating tool as set forth in claim 16 in which the IR shield comprises a first layer of material disposed against a second layer of material, the first layer of material containing the reflecting face, and material of the first layer having lower emissivity than material of the second layer. ### Claim 18 (depends on 17) The heating tool as set forth in claim 17 in which the IR shield comprises aluminized steel. ### Claim 19 A plastic welding process comprising: a) operating a heater to melt a surface portion of a plastic part at a location where a weld joint is to be created while the heater is also emitting IR radiation in a direction beyond the surface portion where a weld joint is to be created; and b) redirecting IR radiation being emitted beyond the surface portion where a weld joint is to be created by reflecting IR radiation which is incident on an IR shield off a reflecting surface of a first of two layers of the IR shield which are disposed against each other, material of the first layer having lower emissivity than material of a second of the two layers.