Abstract: Polyurethane elastomer fibers with superior mechanical and heat distortion properties are obtained by a method in which (a) a segmented polyurethane polymer is produced on the basis of a macro-diol, an aliphatic diisocyanate, and a chain extender with at least two hydroxy and/or amino groups, where the polymer has a molar excess of isocyanate groups over the hydroxy and/or amino groups from the macro-diol and chain extender; (b) the polyurethane polymer is melt-extruded to form a fiber; and (c) The extruded fiber is subjected to a post-treatment. Steps (a) and (b) are carried out under temperature conditions and within a time interval where essentially no allophanate will be formed, while step (c) is performed under temperature conditions and within a time interval in which the polyurethane polymer is cross-linked through the formation of allophanate.

Abstract: The invention concerns a polyurethane elastomer containing structural units of type (a), in which: the group —O—R1—O—is a macrodiol group with a molecular weight of approximately 500 to 10000, R2 is a bivalent aliphatic, cycloaliphatic and/or aliphatic-cycloaliphatic group; and X is a short-chain olefinically unsaturated group, Y is NH or O, n is an integer from 1 to 10 and m is an integer of at least 4. The invention also concerns a method of preparing this polyurethane elastomer which can be melt-spun to form fibres or melt-extruded to form foils. The fibres or foils can be exposed to energy-rich radiation such that crosslinking of the polyurethane occurs. Fibres according to the invention display superior properties in terms of textile-mechanical properties, in particular good tensile strength, elongation at tear, residual elongation and heat distortion temperature.

Abstract: A microdispensing system is useful for the open-jet dispensing of liquids. A valve having a valve chamber is bounded by an impermeable elastic membrane and is filled with the liquid for dispensing. One or more liquid supply lines lead to the valve chamber. An outlet closed from the exterior by the membrane in the position of rest leads from the chamber to a dispensing nozzle. An actuator chamber is disposed on the other side of the membrane. In the actuator chamber, an electromechanical drive is connected to the membrane for the purpose of briefly lifting the membrane from the outlet. The actuator chamber is closed in such manner that it can be subjected to a pressure differing from atmospheric pressure.

Abstract: A fastener driving tool capable of locating a preformed hole in a first workpiece and driving a nail therethrough and into a second workpiece to attach the first workpiece to the second workpiece. The tool comprises a body having a main portion and a handle portion, a guide body, a drive track in the guide body, a driver axially shiftable in the drive track, a fastener containing magazine, a magazine cover, a manual trigger, and a trigger enabling safety. The magazine cover is supported by the guide body and the handle portion of the tool and contains the magazine. The magazine communicates with the drive track and is supported by a slide captively mounted on the guide body and axially shiftable therealong.

Abstract: The present invention relates to a process for coloring polytrimethylene terephthalate fibers by treating the fibers with an aqueous liquor containing at least one dispersing colorant, in the absence of a carrier and the application of pressure. The temperature of the treatment is carried out at or below the boiling point of the liquid, within 20.degree. C. of the boiling point of the liquor. The coloring process begins at a liquor temperature between 20.degree. and 50.degree. C., and the temperature is raised over a period of 20 to 90 minutes. The liquor is then cooled to a temperature between 20.degree. and 50.degree. C., preferably at a rate of cooling of 1.degree. C. per minute, so that at least 95% wt. % of the colorant is absorbed by the fibers, and the dispersing colorant penetrates the fibers to a relative depth of at least 5% with respect to the diameter of the fibers.

Abstract: A hammer drill or chipping hammer includes a housing, a striking mechanism movably displaceably mounted within the housing, and a handle spring supported on the housing. To absorb vibrations generated during operation of the drill or hammer, piston-like weighted members are slidably mounted in the housing for movement parallel to the axial direction of the striking mechanism. The weighted members are supported by springs. Each weighted member is located within a separate cylinder and divides the cylinder into separate spaces. The spaces in the cylinders are interconnected by a fluid medium communicating between them for effecting balanced operation of the weighted members.