Abstract: A system and method are provided for characterizing ST segment (STS) variations of a patient. The method includes collecting STS variations for multiple data collection periods, calculating multiple statistical parameters based on the collected STS variations, and constructing a STS variation trend. The statistical parameters are associated with a corresponding data collection period. The STS variation trend is based on the multiple statistical parameters over multiple data collection periods.

Abstract: The invention is a method for controllably cooling at least a portion of a part-cake from a laser sintering system to minimize cool down time, maximize throughput, and minimize thermal gradients within the part-cake. The method generally comprises forming one or more thermal transfer channels within the part-cake. The thermal transfer channels can include ducts and cooling fins in the part-cake surrounding the formed part. The method can further comprise removing unfused powder from the ducts and introducing cooling media into the ducts. The invention also includes a part-cake having thermal transfer channels formed therein and a laser sintering apparatus comprising a part-cake containing cylinder having permanent fittings therein for receiving terminal portions of thermal transfer channels formed in the part-cake.

Abstract: A convection cooling technique for selective deposition modeling utilizing a venturi duct to establish a low-pressure port for drawing a second flow of air into the duct. The second flow of air is drawn across a heat generating component in the selective deposition modeling apparatus. A low-pressure zone is established at the low-pressure port sufficient to meet the head loss that results when drawing the second flow across the heat generating component and into the venturi duct. A desired flow rate is achieved at a pressure drop that is greater than that possible by the direct use of a fan. The cooling system is well suited for use in providing steady state cooling of radiation exposure systems used in selective deposition modeling to initiate curing of the layers of dispensed material.

Abstract: A cooling system for removing heat from the layers of a three-dimensional object built in a layerwise manner from a build material in a solid freeform fabrication apparatus. The cooling system provides an air duct that delivers a uniform sheet of air flow over the layers of the three-dimensional object while it is built. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: A method and apparatus for effectively removing gas bubbles in systems fed to ink-jetting devices. The system removes both small and large-scale gas bubbles from systems that feed materials to ink jet print heads.

Abstract: A post processing apparatus for automated removal of support material from a three-dimensional objected formed from a build material by selective deposition modeling is provided. The apparatus includes a heated main chamber into which is placed the three-dimensional object with the support material attached and first and second liquid heat transfer medium storage reservoirs. The storage reservoirs reversibly provide liquid heat transfer medium to the main chamber to immerse the three-dimensional object and the attached support material for desired periods of time to meltingly separate the support material from the object.

Abstract: A by-product waste material removal system for solid deposition modeling. As excess build and support material is removed during the build as a by-product waste the removal system accumulates, measures, and releases the by-product waste material into a waste receptacle for disposal. The by-product waste material removal system requires no mechanical vacuum systems and allows operator intervention to remove and replace waste receptacles without interrupting an ongoing build.

Abstract: A convection cooling technique for selective deposition modeling utilizing a venturi duct to establish a low-pressure port for drawing a second flow of air into the duct. The second flow of air is drawn across a heat generating component in the selective deposition modeling apparatus. A low-pressure zone is established at the low-pressure port sufficient to meet the head loss that results when drawing the second flow across the heat generating component and into the venturi duct. A desired flow rate is achieved at a pressure drop that is greater than that possible by the direct use of a fan. The cooling system is well suited for use in providing steady state cooling of radiation exposure systems used in selective deposition modeling to initiate curing of the layers of dispensed material.

Abstract: A cooling system for removing heat from the layers of a three-dimensional object built in a layerwise manner from a build material in a solid freeform fabrication apparatus. The cooling system provides an air duct that delivers a uniform sheet of air flow over the layers of the three-dimensional object while it is built. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

Abstract: A ventilation and cooling system for a selective deposition modeling apparatus dispensing a curable material. The ventilation and cooling system captures airborne contaminants in the apparatus making the apparatus suitable for use in an office environment. A pressure drop is established within the apparatus to assure that all air that enters the apparatus passes through a filter which captures the airborne contaminants before the air is expelled from the apparatus. Sensors are provided to assure that the ventilation and cooling system is function properly, and if not, the apparatus is either shut down or a signal is provided to the operator indicating that the system is not functioning properly.

Abstract: A material feed system for solid freeform fabrication. The build material is delivered in discrete or quantized amounts by the feed system in a non-flowable state to the dispensing device and the material is then changed to a flowable state prior to being dispensed. The feed system can be used to build three-dimensional objects in color, if desired. In one embodiment individual cartridges with build material are loaded into a magazine on the feed system which is integrated with a waste removal system. As the build material is expelled from the cartridges, waste material is deposited into the cartridge. Once all the build material has been expelled, the waste material is hermetically sealed in the spent cartridge which is then ejected from the system. The hermetically sealed cartridges protect operators from contact with the reactive waste material making the system safe for the office environment.

Abstract: A cooling system for removing heat from the layers of a three-dimensional object built in a layerwise manner from a build material in a solid freeform fabrication apparatus. The cooling system provides an air duct that delivers a uniform sheet of air flow over the layers of the three-dimensional object while it is built. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: A selective deposition modeling apparatus utilizing a planarizer to dimensionally normalize the layers of a three-dimensional object as it is being built. The apparatus includes a means for measuring the power used to dimensionally normalize the layers which is indicative of the amount of excess build material that has been dispensed. The apparatus then utilizes the measurement to alter the excess amount of build material of a next dispensed layer so as to optimize the build rate and reduce the production of waste material. In one embodiment the planarizer is rotated at a constant angular velocity by a motor and the current supplied to the motor is monitored, and a print head supplied with a firing voltage is used to dispense the build material. The voltage supplied to the print head is adjusted to optimize the build rate of the apparatus.

Abstract: A ventilation and cooling system for a selective deposition modeling apparatus dispensing a curable material. The ventilation and cooling system captures airborne contaminants in the apparatus making the apparatus suitable for use in an office environment. A pressure drop is established within the apparatus to assure that all air that enters the apparatus passes through a filter which captures the airborne contaminants before the air is expelled from the apparatus. Sensors are provided to assure that the ventilation and cooling system is function properly, and if not, the apparatus is either shut down or a signal is provided to the operator indicating that the system is not functioning properly.

Abstract: A convection cooling technique for selective deposition modeling utilizing a venturi duct to establish a low-pressure port for drawing a second flow of air into the duct. The second flow of air is drawn across a heat generating component in the selective deposition modeling apparatus. A low-pressure zone is established at the low-pressure port sufficient to meet the head loss that results when drawing the second flow across the heat generating component and into the venturi duct. A desired flow rate is achieved at a pressure drop that is greater than that possible by the direct use of a fan. The cooling system is well suited for use in providing steady state cooling of radiation exposure systems used in selective deposition modeling to initiate curing of the layers of dispensed material.

Abstract: An improved selective deposition modeling method which produces a cold weld joint in an object formed by dispensing a single phase change material. The cold weld joint can be controlled so that a lower portion of the object can serve as a support structure for forming the upper portion of the object. Upon separation of the lower and upper portions along the cold weld joint, a downward facing surface is revealed on the upper portion exhibiting superior detail and quality compared to other downward facing surfaces created by conventional selective deposition modeling techniques. The method can readily be adapted for use by selective deposition modeling machines utilizing ink jet print heads dispensing a single phase change material.

Abstract: An improved layer normalizing device for use in dimensionally normalizing layers of a three-dimensional model produced by a selective deposition modeling technique. The layer normalizing device employs a wicking member having a body and a normalizing surface for dimensionally normalizing the object while the object is being built layer by layer. The body includes a plurality of interstices, and when the wicking member is sufficiently heated to cause the build material to become flowable, excess material is drawn by capillary action from the layer of the object being normalized and into the wicking member. A refreshing means is provided to remove the excess build material from the interstices of the wicking member and allow the wicking member to draw additional build material by capillary action.

Abstract: A cooling system for removing heat from the layers of a three-dimensional object built in a layerwise manner from a build material in a solid freeform fabrication apparatus. The cooling system provides an air duct that delivers a uniform sheet of air flow over the layers of the three-dimensional object while it is built. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.

Abstract: A unique scanning technique for selective deposition modeling wherein the dispensing device remains substantially stationary as the object staging structure supporting the three-dimensional objects being formed is reciprocally driven in a main scanning direction. A more uniform temperature environment is provided for the dispensing device which can achieve a more uniform drop mass when dispensing a curable material. Also provided is a unique biased air flow for cooling the layers of the object as they are formed as they release a substantial amount of exothermal heat. The biased air flow is directed away from the dispensing device so a to provide a more uniform temperature environment for the dispensing device while removing the substantial amount of heat from the layers.

Abstract: A material feed system for solid freeform fabrication. The build material is delivered in discrete or quantized amounts by the feed system in a non-flowable state to the dispensing device and the material is then changed to a flowable state prior to being dispensed. The feed system can be used to build three-dimensional objects in color, if desired. In one embodiment individual cartridges with build material are loaded into a magazine on the feed system which is integrated with a waste removal system. As the build material is expelled from the cartridges, waste material is deposited into the cartridge. Once all the build material has been expelled, the waste material is hermetically sealed in the spent cartridge which is then ejected from the system. The hermetically sealed cartridges protect operators from contact with the reactive waste material making the system safe for the office environment.