Showing papers on "Heat sink published in 1972"

Electronic module using flexible printed circuit board with heat sink means

Abstract: An electronic circuit component having particular utility in multi-layer circuit board construction formed essentially of a flexible dielectric sheet of material used as the board base to which is attached circuit runs etched from copper sheets clad to the dielectric sheet prior to etching. Generally, circuitry runs are separated according to alignment with either the X or Y axis with the runs on each side of the dielectric sheet being parallel to only one of those axes. Integration of communication between X and Y runs is by means of plated through holes to which circuit elements may be attached. Flatpack integrated circuits are attached to the board oriented with their covers toward and their heat sink base portions away from the board. By placing all flatpacks on one side of the flexible board structure and looping the structure back on itself, a high circuit component density can be achieved with the heat sink portions of flatpacks exposed exteriorly of the loops of the structure facilitating placing the flatpacks in heat conducting contact with a casing.

Device for the absorption and emission of heat

Abstract: In a device for the absorption and release of heat, two largesurface elements are provided, of which one emits the heat and acts as a heat source and the other absorbs the heat and acts as a heat sink. These two large-surface elements are joined to each other with pipes connected in parallel which are in good heat conducting contact with the large-surface elements. The internal space of the pipes is closed and filled with a heat carrier in a state of saturated vapour within the operating range.

Variables affecting the nature of the chill zone

Abstract: Structures and substructures in the chill zone have been studied in Al-Cu alloys as a function of the following solidification conditions at the substrate chill: a) heat sink capacity; b) surface microprofile; c) nature of the liquid metal fluid flow as it makes substrate contact. The parameters taken in account both experimentally and analytically are: heat transfer coefficient of the metal/mold interface, surface rugosity of the mold walls, and the Reynolds number of the liquid metal fluid flow. The results obtained show definite correlations between the structural characteristics of the chill zone and the values of the studied parameters.

Refrigerator box with door mounted refrigeration unit

Abstract: A refrigerator box has its refrigeration unit incorporated into the door thereof. A pair of thermoelectric cooling modules are attached to a ''''cold'''' bar with their ''''cold'''' surfaces abutted thereagainst. Attached to the cold bar is a heat exchanger element having a plurality of fins for effectively cooling the inside of the box, this heat exchanger forming a heat sink which is mounted adjacent to the inside wall of the box door. The ''''hot'''' surfaces of the thermoelectric modules are attached to a heat exchanger which has fins, this heat exchanger being mounted adjacent to the outside wall of the door. The second heat exchanger provides a heat sink for dissipating heat energy drawn from and through the thermoelectric modules. An air circulation system is provided by means of a blower mounted adjacent the outside wall of the door for circulating ambient air through the outside heat exchanger. This blower is kept in operation both by power from a power source which is the same one used for the thermoelectric units and by power supplied by the thermoelectric units themselves when the regular power supply is disconnected by the unit''s control thermostat.

Temperature controlled mobile cart

Abstract: A mobile cart is provided with thermoelectric cooling means actuated by a circuit which provides for either external A. C. current input or integral D. C. current power supply. A cabinet is specially constructed to pass air through a finned heat sink for heat transfer purposes and through the controlled temperature container portion of the cart.

Circuit breaker with heat pipe cooling means

Abstract: A multi-phase electric circuit control device mounted in a switchboard includes a heat pipe for each phase, having one end in close thermal contact with a relatively high-temperature point of the control device and extending behind the device. The heat pipe has heat-dissipating fins positioned in a portion of the switchboard where natural circulation of the air serves to carry heat away and thereby dissipate heat from the high-temperature point of the control device, making it possible for the control device to carry more current than it would otherwise be able to do safely. In one form, heat is drawn from a point intermediate to the ends of the control device by a heat pipe and heat transfer means extending through an opening in the back wall of the casing of the device. In another form, the heat pipe transfers heat away from the circuit control device terminals.

Fluid Mechanics of Heat Disposal from Power Generation

Abstract: The problem of disposing of the waste heat produced as a result of the generation of electrical energy has its roots in the growth of demand for electrical power and in the economics of power production. Electrical gen­ erating capacity in the United States is expected to continue doubling each decade. As hydroelectric sites are developed to their full capacity, the de­ mand will be met increasingly by fossil-fuel and nuclear steam plants. Regional economics and economics of scale have resulted in increases in plant size and concentrations of waste heat. The efficiency of steam-electric power production by either fossil or nu­ clear fuels is governed by the thermodynamics of the heat cycle. The ideal or Camot efficiency is determined by the temperature of the heat source and by the temperature of the surrounding air or water, which acts as a heat sink. The ideal efficiency is given by

X-ray tube anode target

Abstract: An X-ray tube having a rotating anode comprising a target which is provided with improved heat dissipation or compensation characteristics by means of an X-ray generating member and an associated heat sink of high thermal storage capacity material which during operation of the tube more closely engages the X-ray generating member for providing efficient thermal conductivity therebetween.

Isolated heat-sink semiconductor device

Abstract: Plastic encapsulated power semiconductor devices, such as controlled rectifiers, triacs and power transistors, are disclosed in which the semiconductor body of the device is electrically isolated from the combination heat sink and mounting plate of the device by a thin ceramic electrically insulative plate of high thermal conductivity which provides bonding sites for anchoring the inner ends of the external leads associated with the semiconductor body. One of the external leads bonded to the insulative plate has a portion underlying the semiconductor body and providing an electrically conductive path of high thermal conductivity for heat extraction from the semiconductor body.

Oil spray cooled, brushless, variable speed direct current generator

Abstract: An oil cooled generator has a plurality of diodes for converting alternating current power to direct current power. The diodes are mounted on heat sinks exteriorly of the generator so the diodes can be assembled to and disassembled from the generator without dismantling the generator. The heat sinks are cooled by spraying oil on finned surfaces of the heat sinks inside the generator and by circulating cooling oil at turbulent velocity between the diodes and heat sinks over major portions of the diode mounting surfaces for directly cooling the diodes and heat sinks.

Heat transfer between dispersed liquid metals and gases in packed beds

Abstract: The rates of heat transfer occurring during the counter-current contacting of dispersed liquid metals and gases in towers packed with ring and spherical packings are examined. Using mercury and air as the heat exchange fluids, heat transfer studies at room temperature are described and the heat transfer mechanisms examined. Heat transfer data are also presented for the contacting of molten lead with preheated nitrogen in a pilot plant scale apparatus. Utilizing the mercury irrigated tower as a room temperature analogue of the high temperature apparatus, the mechanisms operating at high temperature (400° to 600°C) are examined. Two basic heat transfer mechanisms operate below about 400°C: the direct mechanism, which refers to convective heat transfer across the gas/liquid metal interface, and the indirect mechanism, a complex process involving conduction and convection in a sequence such as liquid metal-solid packing-gas phase. Above about 400°C, another mechanism, radiation heat transfer between the liquid metal and its environment, is thought to become significant, but experimental errors masked its detection in the present study.

Arrangement for regulating supply of heat from a heat accumulating device

Abstract: A heat accumulating device includes a double-walled reservoir filled with a material suitable for storing heat and provided with heating means for heating the material. The free space bounded by the double walls of the reservoir accomodates a plurality of foil radiation screens and the free space is further filled with a hydrogen atmosphere. The hydrogen filled free space is in communication with a reservoir containing a thermally reversible hydrogen getter. By regulation of the temperature of the hydrogen getter by means of an electric heater associated therewith, the hydrogen pressure in the free space and hence thermal conductivity of the free space is controlled whereby the transfer of heat through the walls of the reservoir from the heat storage material is readily regulated. Means may be provided to effect the supply of heat from the reservoir to the surrounding ambient by forced convection. The free space may be divided into a plurality of compartments completely separated from each other with each compartment being communicating with a separate thermally reversible getter whereby discharge of heat from different portions of the reservoir can be separately regulated.

Solar heat source and receiver system

Abstract: A system for collecting solar heat to meet high power heat requirements as in a Vuilleumier cycle cryogenic refrigerator, in space application. The system includes a short focal-length-to-diameter ratio collector, a heat receiver having a convex surface attached to a heat pipe further containing a heat storage element which is connected to the use, i.e. a cryogenic refrigerator. The heat receiver utilizes a novel coating allowing the system to realize an effeciency in excess of fifty percent.

Isolation mounting for semiconductor device

Abstract: An isolation mounting for a semiconductor device includes a metal heat sink plate to receive heat from the semiconductor device and insulating means to electrically isolate the semiconductor device from the plate which receives the heat. A metal fastener presses the semiconductor device against an insulating wafer which is in turn pressed against the heat sink plate. An insulating liner separates the fastener electrically from metal of the semiconductor device.

Heat flow transducer for thermal surveys

Abstract: Heat flow transducer for use in measuring the geothermal heat flow in the earth. The transducer utilizes copper alloy flexible wire bundles at opposite ends of an elongated body to conduct heat from the strata surrounding a bore hole, into the body of the transducer, and through thermally conductive elements, into contact with a solid state thermopile. The thermopile includes a plurality of semi-conductor elements, electrically in series and thermally in parallel, to produce a usable electrical output at very low heat flows. Multiple modules of semi-conductor elements are employed. The modules are separated by a heat conductive, but electrically insulated layer between modules.

Air directing heat sink mounting of electrical components

Abstract: Electronic component mounting heat sink members for printed wiring cards have heat dissipating fins oriented with respect to the free convection air flow such as to direct heated air out of the equipment in which the components are used.

Electrochemical cell having heat pipe means for increasing ion mobility in the electrolyte

Abstract: A molten salt battery wherein is sunk through the battery case a heat pipe into the electrolyte for the purpose of heating the electrolyte. The heat pipe''s low thermal time constant makes possible rapid temperature control of the electrolyte without regard to the heat sink effect of the battery case of electrodes.

Microelectronic circuit package

Abstract: A package for microelectronic circuits is disclosed in which the mounting mechanism isolates the circuit chip and encapsulating plastic from any applied stress when mounted. The mechanical force of the mounting mechanism is applied to a pair of tabs extending upward from a combination base/heat sink. This permits the applied stress to bypass the encapsulant and be transmitted directly to the heat sink and the mechanical support.

Stackable heat sink assembly

Abstract: An improved heat sink assembly for dissipating the heat generated by a plurality of circuit components having high current ratings wherein the assembly includes a stack of heat conductive mounting plates and improved heat sink members arranged in a stack and held therein by a cage-like construction including a number of insulated tension rods secured to and spanning the distance between a pair of spaced base plates between which the stack of parts, including the circuit components, the mounting plates and the heat sink members, are disposed. One of the base plates has means thereon for applying pressure to the stack of parts. Each heat sink member is formed from an extrusion and an improved electrical connection is provided for at least one of the mounting plates.

Uncooled gallium-aluminum-arsenide laser illuminator

Abstract: A compact room temperature laser illuminator is provided. A cylindrical design allowing both radial and axial power and heat flow is employed. A stepped heat sink provides adequate cooling for close packed diodes. Shape and placement of electronic and optical elements as well as their composition materials are combined to insure unusually high reliability, small size, and low weight.

Thermal switch-heat pipe

Abstract: A radial heat pipe is fitted with a wick and working fluid for the temperature of interest and operated in such a manner as to act as a thermal switch. The heat pipe surrounds nuclear fuel elements and during normal temperature operation transports negligible energy but upon a surge in fuel element temperature large amounts of heat can be transported to limit the fuel element temperature.

Method of making metal semiconductor diodes having plated heat sink members

Abstract: A SIGNIFICANT IMPROVEMENT IN THE HEAT FLOW RESISTANCE OF MICROWAVE DIODES MAY BE ACHIEVED BY PLATING A HEAT SINK TO THE METAL LAYER OF A SCHOTTKY BARRIER STRUCTURE. A SEMICONDUCTOR SUBSTRATE HAS AN EPITAXIAL LAYER GROWN THEREON IN ACCORDANCE WITH STANDARD EPITAXIAL PROCEDURES. THE SCHOTTKY BARRIER IS THEN FABRICATED BY PROPERLY PREPARING THE SURFACE OF THE EPITAXIAL LAYER AND THEN EVAPORATIVELY DEPOSITING A LAYER OF METAL AT A TEMPERATURE SUCH THAT THE METAL NUCLEATES TO FORM A VERY THIN FILM TO PRODUCE A RECTIFYING CONTACT WITH THE EPITAXIAL LAYER. A HEAT SINK MATERIAL IS THEN PLATED ONTO THE METAL FILM OF THE RECTIFYING CONTACT TO A THICKNESS SUFFICIENT TO INSURE HEAT CONDUCTION AWAY FROM THE SCHOTTKY BARRIER. TYPICALLY, THE HEAT SINK MAY BE PLATED COPPER.

Heat valve device

Abstract: Heat valve devices especially suitable for controlling heat flow from a heat source to a heat sink are disclosed. These devices each include an elongated tubular housing of low thermal conductivity being closed at both ends. A capillary wick lining the inner lateral surface of the housing is adapted to convey a volatile working fluid such as water from one end to the other. A sealed working fluid reservoir adapted to being heated is in fluid communication with the housing.

High voltage current limiting fuse including heat removing means

Abstract: A current limiting fuse structure comprising a plurality of elements of fusible material adapted for higher voltage circuit operation. Each fuse element has a plurality of areas of reduced cross-section to facilitate the generation of a plurality of arclets at the time of melting to limit electrical current in the circuit to be protected by the fuse during the blowing of the fuse. The fuse elements and/or adjacent pulverulent arc quenching material are enclosed by a housing or casing which may be formed from ceramic material. Edges of each fuse element are disposed in intimate physical or structural contact with the associated casing to facilitate the removal or transfer of heat which may be generated in the areas of reduced cross section. The material from which the casing is made is such a composition or type that is a relatively good electrical insulator so as to withstand the voltage of the protected circuit once the fuse has blown and is also a good conductor of heat so as to efficiently remove heat from the enclosed fuse elements. The casing may be formed from a plurality of sections which may be joined to each other and the terminals of the fuse by high temperature epoxy cement. A metallic heat exchanger or heat sink may be assembled or disposed in intimate contact with an outside surface of the casing either by bolting or by using a suitable bonding material cement so that the heat which may be generalized in the enclosed fuse and which may be conducted away from the fuse elements by the casing may be further conducted to the air or similar environment through the associated heat exchanger.

Novel diamond particle particularly for use in heat sinks

Abstract: The invention provides a rounded diamond particle, which is preferably of the Type IIa, truncated by a single planar surface or by a planar surface at each of opposed poles. These particles find particular use in heat sinks for electronic devices, the heat sink consisting of a body of a metal of good heat conductivity such as copper and a truncated diamond particle in thermal contact with the body such that a planar surface is presented away from the body and thus able to make thermal contact with an electronic device.

Multilayer heat sink

Abstract: An improved heat sink comprises an integral metallic structure, having upper and lower layers of different metals, respectively, fixed to each other to provide a common interface. The lower layer has a greater coefficient of thermal expansion than the upper layer. An upwardly extending dimpled portion of the upper layer is formed by a dent that extends upwardly from the common interface. When the heat sink is heated by a heat-producing device mounted on the surface of the dimpled portion, the lower layer tends to expand in an opposite direction to that of the dimpled portion of the upper layer, so that the dimpled portion is in compression, thereby limiting the amount of thermal expansion and distortion that would normally occur at the surface of the dimpled portion.

Arrangement for adhesively joining heat-dissipating circuit components to heat sinks and method of making them

Abstract: This invention relates to a method and an arrangement of mounting semiconductor elements on heat sinks. The switching element is glued inseparably to an intermediate layer consisting of cleavable material. One side of the intermediate layer is glued inseparably to the heat sink. If a defective switching element has to be replaced, a moderate impact on the mounting plate of the element in parallel to the surface of the heat sink is sufficient to cause an exact cleavage.