Limiting dispersion of ir radiation from a heater element during plastic welding
AssigneeSPM Automation (Canada) Inc.
InventorsRade Pupovac, Zachary Touesnard, Christian Peter Holtkamp, Boris Novakovic
Life of this patent
Estimating the term…
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.
Claims19
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.
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.
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.
Dependencies are inferred from the claim text.