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 heater is provided that includes a resistive layer formed by a layered process (e.g., thick film, thin film, thermal spray, and sol-gel) and two electrical lead wires connected to the resistive layer. The resistive layer has sufficient temperature coefficient of resistance characteristics such that the resistive layer is a heater element and a sensor, and the resistive layer is in communication with a two-wire controller through the two electrical lead wires. Preferably, the sensor is a temperature sensor, and the heater includes additional layers formed by layered processes.

Abstract: An instrumented heater sleeve is provided that has a plurality of zones, a dielectric layer disposed over an outer surface of the sleeve, a resistive element layer disposed over the first dielectric layer, and a plurality of pairs of lead wires secured to a portion of the resistive element layer. Each pair of lead wires is connected to and corresponds with each of the zones and a protective layer is disposed over the dielectric layer. An amount of power is supplied to each of the zones and adjusted during a test run, or multiple test runs, to achieve a desired temperature profile along a heating target such as a hot runner nozzle. Methods of designing a hot runner nozzle heater using the instrumented heater sleeve are also provided.

Abstract: A method of forming a layered heater includes forming a continuous resistive layer over a substrate, forming conductive overlays in predetermined areas of the resistive layer, and removing portions of the continuous resistive layer between the conductive overlays to form a plurality of single cuts extending between the conductive overlays. The single cuts extend through the continuous resistive layer between the conductive overlays and longitudinally into a portion of the corresponding conductive overlays. Preferably, the single cuts are formed using a laser.

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: 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 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 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: A layered heater system is provided that includes an engineered substrate having an upper face sheet, a lower face sheet, and a core disposed between the upper face sheet and the lower face sheet. A dielectric layer is formed on at least one of the upper face sheet and the lower face sheet, a resistive element layer is formed on the dielectric layer, a protective layer is formed on the resistive element layer, and terminal pads are formed over at least a portion of the resistive element layer, wherein the terminal pads are exposed through the protective layer. In one form, the core defines a honeycomb structure, and in another, the core defines a frame structure having a plurality of support ribs.

Abstract: A heater assembly is provided that includes a substrate having opposed end portions defining raised flanges, a slot extending between the opposed end portions, and opposed chamfered surfaces extending along the slot and across the raised flanges. In one form, a plurality of layers are disposed onto the substrate, along with a pair of terminal pads. A protective cover defining at least one aperture is disposed over the layers and is secured to the raised flanges and the opposed chamfered surfaces of the substrate, and the aperture is disposed proximate the terminal pads. A pair of lead wires is secured to the pair of terminal pads, and a lead cap assembly is disposed around the pair of lead wires and is secured to the protective cover. Methods of manufacturing the heater assembly are also provided in accordance with the present disclosure.

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: An instrumented heater sleeve is provided that has a plurality of zones, a dielectric layer disposed over an outer surface of the sleeve, a resistive element layer disposed over the first dielectric layer, and a plurality of pairs of lead wires secured to a portion of the resistive element layer. Each pair of lead wires is connected to and corresponds with each of the zones and a protective layer is disposed over the dielectric layer. An amount of power is supplied to each of the zones and adjusted during a test run, or multiple test runs, to achieve a desired temperature profile along a heating target such as a hot runner nozzle. Methods of designing a hot runner nozzle heater using the instrumented heater sleeve are also provided.

Abstract: A layered heater includes a resistive layer defining a resistive circuit pattern having at least one bend portion. A conductive overlay is provided on at least one of a top surface and a bottom surface of the bend portion to alleviate the current crowding effect, thereby protecting the electric circuit from premature failure. Methods of manufacturing the layered heater are also disclosed. The overlay may be formed on the bend portion after the resistive layer is formed. The overlay may also be formed on a substrate or a dielectric layer that supports the resistive layer before the resistive layer is formed.

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 layered heater is 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 hot runner nozzle heater is provided that includes a sleeve defining a slot extending along a length of the sleeve. A first dielectric layer is disposed over an outer surface of the sleeve, and a resistive element layer is disposed over the first dielectric layer, wherein the resistive element layer defines a resistive circuit pattern that is preferably formed by a laser trimming process. A pair of terminal leads are secured to a portion of the resistive element layer thus defining a termination area, and the termination area is positioned proximate the slot and away from the proximal end and the distal end of the sleeve. A second dielectric layer is disposed over the resistive element layer but not over the termination area, a third dielectric layer is disposed over the termination area, and a protective layer disposed over the second dielectric layer and the third dielectric layer.

Abstract: A heater is provided that includes a resistive layer formed by a layered process (e.g., thick film, thin film, thermal spray, and sol-gel) and two electrical lead wires connected to the resistive layer. The resistive layer has sufficient temperature coefficient of resistance characteristics such that the resistive layer is a heater element and a sensor, and the resistive layer is in communication with a two-wire controller through the two electrical lead wires. Preferably, the sensor is a temperature sensor, and the heater includes additional layers formed by layered processes.

Abstract: A tool for removing a split-sleeve heater from a target object, such as a hot runner nozzle body, is provided that includes a handle, a shaft extending from the handle, and a protrusion disposed around at least a portion of a distal end portion of the shaft. The protrusion defines a shoulder, and the shoulder is adapted to engage a removal feature of the split-sleeve heater. In another form, a split-sleeve heater is provided that includes a heater body having opposed ends and a slot extending between the opposed ends. A recess is formed conjointly with the slot proximate at least one of the opposed ends, which is adapted for engagement by a removal tool. Methods of operating the tool and forming the slot of the split-sleeve heater are also provided.

Abstract: A hot runner nozzle heater is provided that includes a sleeve defining a slot extending along a length of the sleeve. A first dielectric layer is disposed over an outer surface of the sleeve, and a resistive element layer is disposed over the first dielectric layer, wherein the resistive element layer defines a resistive circuit pattern that is preferably formed by a laser trimming process. A pair of terminal leads are secured to a portion of the resistive element layer thus defining a termination area, and the termination area is positioned proximate the slot and away from the proximal end and the distal end of the sleeve. A second dielectric layer is disposed over the resistive element layer but not over the termination area, a third dielectric layer is disposed over the termination area, and a protective layer disposed over the second dielectric layer and the third dielectric layer.

Abstract: A 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. 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.