Abstract: A locking device for convertible tops has a four-joint construction with a support frame connected to the roof, a handle, a joint bracket and a lever. At the extended end of the lever, a locking hook, which can be swiveled around an axis, is fastened. This locking device is modified so that a precise control of the locking hook, and with that, a convenient course of operations during the closing of the top becomes possible and, moreover, accident safety is improved. For this purpose, a connecting-link guidance and a spring, which exerts a torque on the hook, are provided for the locking hook.

Abstract: Crosslinked, water-swellable copolymers are produced with a crosslinking agent comprising an N-(2'alkenyl)-3-methylenepyrrolidin-2-one of the formula ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are the same or different and each is hydrogen or alkyl having 1 to 6 carbon atoms.

Abstract: Sand or rock masses containing mineral oil are deoiled with a deoiling agent containing an aqueous solution of a water-soluble copolymer which is a random distribution of 5 to 60% of weight of units of the formula ##STR1## 2 to 40% by weight of units of the formula ##STR2## 38 to 93% by weight of units of the formula ##STR3## and partial hydrolysates thereof, wherein when R.sup.1 is hydrogen, R.sup.2 is hydrogen, methyl or ethyl, Y is --CO--NH--C(CH.sub.3).sub.2 --CH.sub.2 -- or a direct bond, and X.sup..sym. is a cation; when R.sup.1 and R.sup.2 are identical or different, each is hydrogen, methyl, ethyl or, together are trimethylene, Y is --CO--NH--C(CH.sub.3).sub.2 --CH.sub.2 -- and X.sup..sym. is a cation.

Abstract: Sand or rock masses containing mineral oil are deoiled with a deoiling agent containing an aqueous solution of a water-soluble copolymer which is a random distribution of 5 to 60% of weight of units of the formula ##STR1## 2 to 40% by weight of units of the formula ##STR2## and 38 to 93% by weight of units of the formula ##STR3## and partial hydrolysates thereof, wherein when R.sup.1 is hydrogen, R.sup.2 is hydrogen, methyl or ethyl, Y is --CO--NH--C(CH.sub.3).sub.2 --CH.sub.2 -- or a direct bond, and X.sup..sym. is a cation; when R.sup.1 and R.sup.2 are identical or different, each is hydrogen, methyl, ethyl or, together are trimethylene, Y is --CO--NH--C(CH.sub.3).sub.2 --CH.sub.2 -- and X.sup..sym. is cation.

Abstract: A pipe line has a check valve therein, operable by an actuator. The actuator is connected to be operated by fluid pressure from the pipe line, and is connected with the pipe line by a control circuit including valve means. A differential pressure valve is connected in the control circuit, and is constructed to sense a drop in pressure within the pipe line downstream of the control valve. Upon sensing such a pressure drop, the differential pressure valve is effective to cause connection of the actuator to pipe line pressure upstream of the check valve, whereby the latter is automatically closed.

Abstract: A tool head mounting arrangment in a turning machine of the type having a carrier and tool head clamped against seating surfaces therein. The tool head is adjustable in position relative to the workpiece. The carrier contains an opening for receiving the tool head. The opening includes an upper seating surface and a lower seating surface against which the tool head rests.