Abstract: A layered heater is provided that includes at least one resistive layer having a resistive circuit pattern, the resistive circuit pattern defining a length, a width, and a thickness, wherein the thickness varies along the length of the resistive circuit pattern and/or the width of the resistive circuit pattern for a variable watt density. The present disclosure also provides layered heaters having a resistive circuit pattern with a variable thickness along with a variable width and/or spacing of the resistive circuit pattern in order to produce a variable watt density.

Abstract: A hot runner nozzle heater system is provided with a layered heater in communication with a two-wire controller, wherein a resistive layer of the layered heater is both a heater element and a temperature sensor. The two-wire controller thus determines temperature of the layered heater using the resistance of the resistive layer and controls heater temperature through a power source.

Abstract: Methods of assembling a high heat transfer and tailored heat transfer layered heater systems are provided. One method includes a step of pressing one of a target part and a layered heater into the other one of the target part and the layered heater to create an interference fit between the layered heater and the target part. When the target part is disposed within the layered heater, the layered heater includes a substrate defining an inner periphery less than or equal to an outer periphery of the target part. When the layered heater is disposed within the target part, the layered heater includes a substrate defining an outer periphery larger than or equal to an inner periphery of the target.

Abstract: A heater system and related methods of heating a surface are provided by the present disclosure that includes, in one form, a substrate defining a heating surface and a layered heater formed on the heating surface. A plurality of nodes are disposed along the heating surface and are in electrical contact with a resistive heating layer of the layered heater, along with a plurality of lead wires connected to the plurality of nodes. In one form, a multiplexer is in communication with the plurality of nodes through the plurality of lead wires, and a controller is in communication with the multiplexer, wherein the multiplexer sequences and transmits resistances from the plurality of nodes to the controller, and the controller controls an amount of power provided to each of the plurality of nodes based on the differences in resistances between the nodes.

Abstract: A layered heater is provided with a resistive layer having a resistive circuit pattern, the resistive circuit pattern defining a length and a thickness, wherein the thickness varies along the length of the resistive circuit pattern for a variable watt density. The present invention also provides layered heaters having a resistive circuit pattern with a variable thickness along with a variable width and/or spacing of the resistive circuit pattern in order to produce a variable watt density. Methods are also provided wherein the variable thickness is achieved by varying a dispensing rate of a conductive ink used to form the resistive circuit pattern, varying the feed rate of a target surface relative to the dispensing of the ink, and overwriting a volume of conductive ink on top of a previously formed trace of the resistive circuit pattern.

Abstract: Methods of forming a layered heater are provided that comprise at least one resistive layer comprising a resistive circuit pattern, the resistive circuit pattern defining a length, a thickness, and a spacing, wherein the thickness varies along the length of the trace of the resistive circuit pattern for a variable watt density. The methods include achieving the variable thickness by varying a dispensing rate of a conductive ink used to form the resistive circuit pattern, varying the feed rate of a target surface relative to the dispensing of the ink, and overwriting a volume of conductive ink on top of a previously formed trace of the resistive circuit pattern.

Abstract: Methods of forming a layered heater are provided with a dielectric layer formed by a first layered process, a resistive layer formed on the dielectric layer, the resistive layer formed by a second layered process, and a protective layer formed on the resistive layer, wherein the protective layer is formed by one of the first or second layered processes or yet another layered process. The first layered process is different than the second layered process in order to take advantage of the unique processing benefits of each of the first and second layered processes for a synergistic result. The layered processes include, by way of example, thick film, thin film, thermal spraying, and sol-gel. Additional functional layers are also provided by the present invention, along with methods of forming each of the individual layers.

Abstract: A heater system is provided that comprises a plurality of layered heater modules, each module comprising a plurality of resistive zones. The layered heater modules are disposed adjacent one another to form the heater system, which can be adapted for a multitude of different sizes of heating targets. Preferably, the resistive zones comprise a plurality of resistive traces arranged in a parallel circuit and oriented approximately perpendicular to a primary heating direction, wherein the resistive traces comprise a positive temperature coefficient material having a relatively high TCR. The resistive traces are responsive to the heating target power gradient such that the resistive traces output additional power proximate a higher heat sink and less power proximate a lower heat sink along the primary heating direction.

Abstract: A layered heater is provided that comprises at least one resistive layer defining a circuit configuration, the circuit configuration comprising at least one resistive trace oriented relative to a heating target and comprising a material having temperature coefficient characteristics such that the resistive trace provides power commensurate with demands of the heating target. In one form, resistive traces of the resistive layer are a PTC material having a relatively high TCR and are oriented approximately perpendicular to a primary heating direction. In another form, resistive traces of the resistive layer are an NTC material having a relatively high BETA coefficient and are oriented approximately parallel to a primary heating direction.

Abstract: A layered heater is provided with a resistive layer having a resistive circuit pattern, the resistive circuit pattern defining a length and a thickness, wherein the thickness varies along the length of the resistive circuit pattern for a variable watt density. The present invention also provides layered heaters having a resistive circuit pattern with a variable thickness along with a variable width and/or spacing of the resistive circuit pattern in order to produce a variable watt density. Methods are also provided wherein the variable thickness is achieved by varying a dispensing rate of a conductive ink used to form the resistive circuit pattern, varying the feed rate of a target surface relative to the dispensing of the ink, and overwriting a volume of conductive ink on top of a previously formed trace of the resistive circuit pattern.

Abstract: A layered heater is provided that comprises a dielectric layer formed by a first layered process, a resistive layer formed on the dielectric layer, the resistive layer formed by a second layered process, and a protective layer formed on the resistive layer, wherein the protective layer is formed by one of the first or second layered processes or yet another layered process. The first layered process is different than the second layered process in order to take advantage of the unique processing benefits of each of the first and second layered processes for a synergistic result. The layered processes include, by way of example, thick film, thin film, thermal spraying, and sol-gel. Additional functional layers are also provided by the present invention, along with methods of forming each of the individual layers.

Abstract: A tailored heat transfer layered heater system is provided that comprises a target part defining a room temperature periphery and a layered heater disposed around or within the target part, the layered heater comprising a substrate having a room temperature periphery that is sized such that an interference fit is formed between the layered heater and the target part either through mechanical or thermal methods. The layered heater in one form is disposed around the target part and in another form is disposed inside the target part. Additionally, heat transfer is tailored along the layered heater using other devices such as thermal spacers, insulative pads, and a transfer substrate in other forms of the present invention.

Abstract: A heater system is provided that comprises a layered heater in communication with a two-wire controller, wherein a resistive layer of the layered heater is both a heater element and a temperature sensor. The two-wire controller thus determines temperature of the layered heater using the resistance of the resistive layer and controls heater temperature through a power source. Furthermore, a heater system using a layered heater in communication with a two-wire controller for a specific application of a hot runner nozzle in an injection molding system is provided by the present invention.

Abstract: An electric, resistance element heater utilizes quartz as a sheath material and has a resistance (heating) element that is in intimate, substantially continuous contact with a surface of the quartz. This allows the heater to operate in any one or all of the three modes of heat transfer, namely, radiation, conduction and convection. Such intimate, substantially continuous contact of the resistance element is achieved by applying the element in direct contact with the quartz surface. This is accomplished by applying a heating circuit directly to the quartz surface, which heating element can be a foil element, or a thick or a thin film deposition element. The overall heater is formed by covering the heater element by a quartz sheath and attaching leads formed on the ends of the heater element to a source of electric energy. Sensors such as thermocouples, RTD's and the like can also be incorporated directly into the heater structure. Also, the heater can be fashioned into a variety of shapes.

Abstract: Various methods are described for assembling and/or coupling heater sections together for assemblage of heaters. The heater sections may be hot or cold heater sections having various geometries, dimensions, and specific electrical resistances. In one method, a cold heater section is assembled onto a pre-fabricated hot heater section with an oversized tube and pre-fabricated insulating cores. In another method, a pre-fabricated cold section is spliced onto a pre-fabricated hot section utilizing pre-fabricated semi-annular insulating cores and an oversized sleeve. In a further method, a first pre-fabricated hot section is spliced onto a second pre-fabricated hot section via an electrically conductive core and an oversized sleeve. These methods allow for the manufacture of stock lengths of hot and cold heater sections, that are then cut to length and coupled together. According to one aspect, the methods reduce tolerance errors in heater length.