Abstract: Fluid-carrying tubes for a heat exchanger are provided with internal longitudinal fins formed separately from the tube itself. One form utilizes individual elongated V-shaped strips biased radially outwardly by an annular sheet metal spring, with the tips of the fins brazed to the inner surface of the tube wall. Second and third embodiments utilize a one-piece corrugated sheet metal cylinder rather than individual strips, but with adjacent fins being almost completely severed from each other to provide sharp edge contact between the tips of the fins and the tube wall for optimum brazing. Either the fins or tube inner wall is clad with a lower-melting point material which permits furnace brazing of the fin tips to the tube wall. All three forms have longitudinally spaced holes and slots to enhance heat exchange by inducing transverse fluid flow through the fins and to allow liquid levels to equalize.

Abstract: In an apparatus for performing various operations on stock material, such as advancing, feeding, measuring, cutting and the like, all under the control of a program on a punched tape, an improved punched tape control system wherein the sprocket holes, which are utilized for advancing the punched tape, are also utilized to convey control information. Data is placed on the tape in the form of perforations on parallel longitudinal tracks or channels and the conventional tape advancing sprocket holes also carry data to both control the advancing of the stock material and to synchronize the advancing of the stock material and the advancing of the punched tape. Stock material is advanced only when a sprocket hole is present in the tape and the tape is advanced only when the stock material is operated on in accordance with the data on the tape.

Abstract: In an apparatus for performing various operations on stock material, such as advancing, feeding, measuring, cutting and the like, all under the control of a program on a punched tape, an improved punched tape control system wherein the sprocket holes, which are utilized for advancing the punched tape, are also utilized to convey control information. Data is placed on the tape in the form of perforations on parallel longitudinal tracks or channels and the conventional tape advancing sprocket holes also carry data to both control the advancing of the stock material and to synchronize the advancing of the stock material and the advancing of the punched tape. Stock material is advanced only when a sprocket hole is present in the tape and the tape is advanced only when the stock material is operated on in accordance with the data on the tape.

Abstract: In an apparatus for performing various operations on stock material, such as advancing, feeding, measuring, cutting and the like, all under the control of a program on a punched tape, an improved punched tape control system wherein the sprocket holes, which are utilized for advancing the punched tape, are also utilized to convey control information. Data is placed on the tape in the form of perforations on parallel longitudinal tracks or channels and the conventional tape advancing sprocket holes also carry data to both control the advancing of the stock material and to synchronize the advancing of the stock material and the advancing of the punched tape. Stock material is advanced only when a sprocket hole is present in the tape and the tape is advanced only when the stock material is operated on in accordance with the data on the tape.