Electronic Controls Design, Inc.

Paul M Austen

Rex L Breunsbach

Bobby Joe Rooks

Examples are described for predicting a thermal profile of a product in an oven using temperature measurements for each zone of the oven. An example method of producing a predicted thermal profile of a product in an oven includes measuring the temperature of each oven zone using a zone temperature sensor as the product transitions through the zone, and calculating the predicted thermal profile of the product using a baseline temperature profile and the measured temperatures of each zone at the time the product is in each zone. Parameters of the predicted thermal profile may be compared to thermal targets corresponding to a process specification for the product in order to determine whether the product was processed according to the process specification.

Profiling an oven

An exemplary embodiment of a temperature probe comprises an elongated shaft having a first portion and a second portion, the first portion being configured for insertion into a unit of food and the second portion being configured to extend outside of the unit of food. The probe further comprises at least two temperature sensors positioned at different longitudinal locations along the first portion of the shaft that are configured to measure temperatures of the unit of food at different locations within the unit of food while the unit of food is being processed thermally. The probe further comprises at least one ambient temperature sensor coupled to the shaft and configured to measure ambient temperature adjacent to the unit of food.

Food temperature probe

Methods and devices for insulating electronic devices are disclosed. The devices include a jacket comprising an absorbing material wetted with a liquid cooling-agent. When the jacket is introduced into a heated process-environment, the liquid cooling-agent evaporates and cools the jacket. The absorbing material can comprise a heat-resistant, organic, polymeric material, such as a network of polyimide fibers.

Thermal insulation for electronic devices

A system is disclosed for determining optimal process settings for a conveyor oven, such as a reflow oven used to reflow solder paste on a PCB assembly. According to a disclosed embodiment, an ideal temperature profile is obtained from the solder paste specifications of the solder paste to be reflowed in the oven. The ideal temperature profile of the paste includes a preheat phase, a soak phase, a reflow phase and a cooling phase. One or more profiles that fit the oven are obtained by aligning the beginning of each phase of the ideal profile with a forward end of an oven zone. The profile that best fits the oven is selected as a target profile for the reflow soldering process. The set points of the oven zones for effecting the target profile when the solder paste is conveyed through the oven are determined.

Conveyor oven profiling system

An oven analyzer for profiling a conveyor oven is disclosed that accurately and precisely determines the physical characteristics of an oven and stores such information so that it can be outputted to a computer for analysis. In one embodiment, the oven analyzer includes a pallet that moves through the conveyor oven. The pallet houses an electronic data logger that is coupled to multiple sensors. The electronic data logger has memory for storing information obtained from the sensors. A first sensor is a temperature sensor that detects the ambient temperature within the oven. A second sensor is mounted within a metal mass of known thermal characteristics and detects the ovens ability to heat an object. A third sensor detects the position of the pallet within the oven. The electronic data logger stores the data received from the sensors in the memory for selective output to a computer for analysis or printing.

Method and apparatus for profiling a conveyor oven

A sensor link is disclosed that simplifies connections between multiple temperature sensors positioned on a test board and a data logger that stores temperature information received from the temperature sensors while passing through the conveyor oven. In one embodiment, the sensor link includes multiple input ports for connecting to the temperature sensors. Conductors within the sensor link connect the multiple temperature sensors to an output port. In one aspect, a single cable extends between the sensor link and a data logger. The data logger stores temperature information received from the temperature sensors while the test board is passed through a conveyor oven. The sensor link can also have additional temperature sensors for providing additional temperature information about the conveyor oven. For example, an ambient temperature sensor may be positioned on the sensor link to provide the ambient temperature of the conveyor oven. A metal mass may also be positioned on the sensor link for providing heat flow information about the conveyor oven. Once all of the desired information is stored in the data logger, such information can be downloaded to a computer for further processing, such as obtaining a profile of the conveyor oven.

Conveyor oven profiler with simplified temperature sensor connection scheme

A system and method for measuring liquid from a liquid dispensing system is disclosed. In an illustrated application, a flux measuring device is described that measures flux dispensed from a flux applicator system. The flux measuring device is a test unit that simulates a printed circuit board. Once the distribution of flux is measured, different parameters in the flux applicator system can be modified to ensure that the proper distribution of flux is applied to printed circuit boards during their manufacture. In one aspect, a mesh board having substantially uniform thickness includes a plurality of spaced-apart holes that extend through the mesh board. The holes are sized so that liquid dispensed from a nozzle that contacts the bottom surface of the mesh board enters the holes and is detected on the top surface of the mesh board. A cover is mounted to the mesh board and uniformly maintains detection material in contact with the top surface of the mesh board. In another aspect, an image is formed on the detection material due to contact with liquid that passes through the holes in the mesh board. Image processing and analysis software may be used to automatically measure the image on the detection material. Based on the measurement, the liquid dispensed from the nozzle or other parameters in the manufacturing process can be modified.

Method and apparatus for measuring spray from a liquid dispensing system

This patent discloses an analyzer that can be mounted onto a wave solder machine and passed through a solder wave to determine various characteristics associated with the solder wave to assist operators with proper set up and trouble shooting. The analyzer comprises a pallet made of a thermally insulated material. The pallet supports a housing that contains a data collector having its own power supply. The pallet further supports a coupon that is made of circuit board material so that test measurements may be made simulating actual circuit board conditions as closely as possible. The pallet can accept coupons of different circuit board types such as multi-layer or double sided. The pallet further has dissimilar wire pairs embedded therein. The wire pairs have terminal portions strategically exposed along a bottom surface of the pallet located in non-contacting, but close proximity to one another. As the dissimilar wire pairs pass through a solder wave, a thermal emf is generated that can be detected by the data collector. Based upon information sensed by the dissimilar wire pairs, the thermocouples mounted to the coupon, and a timer, the data collector is able to determine substantial physical characteristics associated with the solder wave.

Wave solder analyzer

The present invention is an apparatus to clean and cleanliness test printed circuit wiring boards and includes an inner chamber and an outer enclosure encasing the inner chamber. A rack within the chamber is adapted to hold a plurality of PCBs having electronic components assembled thereon. An operator programmable microprocessor controller causes a saponifier solution to be introduced into the interior chamber. The saponifier solution is pumped through a diffusion assembly in the chamber to spray the solution onto the PCBs. Upon completion of this cleaning cycle, the saponifier solution is drained by gravity out of the chamber. This is followed by a water rinsing cycle utilizing the same hardware and procedure. Once the rosin saponification cleaning cycle and water rinsing cycle are complete, the system controller empties the wash chamber and pumps in a standard resistivity test mixture of 75% isopropyl alcohol (IPA) and 25% water. A MIL-P-28809 cleanliness test is then performed on the PCBs. The PCBs are rinsed in the test IPA mixture by the diffusion assembly at a set temperature for a set time. If the test IPA mixture has a resistivity of .ltoreq.2 M.OMEGA./cm.sup.3, the PCBs are determined to be contaminated and are rejected for re-cleaning.

Method and apparatus to clean and cleanliness test printed circuit boards

A cleaning apparatus and method for washing and rinsing electronic assemblies. The apparatus includes a single closable chamber for containing a single tank with attached ultrasonic transducers. Separate wash and rinse fluid circuits each are arranged to fill the tank, to drain fluid from the tank, and to recondition the fluid for reuse. To permit the safe use of combustible solvents, an inert gas purge system evacuates oxygen and combustible vapors from areas with potential electrical ignition sources.

Closed-loop dual-cycle printed circuit board cleaning apparatus and

A batch cleaning system which can use a combustible solvent to clean printed circuit boards or other electronic assemblies is disclosed. An inner enclosure is sealed by a door. A rack for supporting printed circuit boards or other electronic assemblies or the like is mounted inside the inner enclosure. A plurality of spray nozzles are mounted within the inner enclosure. The inner enclosure is purged of air by introducing an inert gas. Combustible solvent is introduced into the bottom of the inner enclosure where it is pumped through the spray nozzles to clean the printed circuit boards. The contamination level of the solvent is measured and recorded. The solvent is drained back into a solvent holding tank upon completion of the cleaning cycle for subsequent reuse during the next cleaning cycle.

Growing community of inventors

Milwaukie, OR, United States of America

Paul M Austen