Abstract: A transparent rear projection screen has a Fresnel lens for paralleling light arriving from behind. In the front surface the screen is provided with grooves which extend in the vertical direction in the position of use of the screen. Each of the side flanks of the grooves adjoins a side part of an adjacent, also vertically extending convex lens. The side flanks of the grooves are totally reflecting to parallelled light arriving from behind in order to increase the deflection in the lateral direction of a part of the light arriving from behind by means of reflection into the adjacent lens. The angle which a side flank forms together with the side part of the adjacent lens is so small that total reflection from the inner surface of the side part of the lense of light which is totally reflected of the side flank in question is avoided. Moreover, between the vertical lenses to which the side flanks adjoin, at least one further lens is arranged.

Abstract: An apparatus for burning pulverulent raw material, in particular cement raw meal to cement clinker, has a kiln (1), a cooler (2), a suspension calciner (4-12) and a multi-stage preheater (14-27). The preheater is provided with two material outlet ducts (22 and 22') directing a first stream of preheated material to a suspension burning chamber (4) with a hot air inlet (7) and a fuel inlet (5) and a second stream of preheated material to a kiln gas duct (28), respectively. Rapid quenching of kiln gas and accelerated rate of combustion in suspension calciner are provided by suspending and calcining the material in the streams in the burning chamber and the kiln gas duct, respectively, and uniting the two suspensions downstream of the suspension burning chamber (4). The calcined material is precipitated in and passed to the kiln from a precipitator (9), to which the united suspensions are directed.

Abstract: Recodable electronic lock where the coding unit which contains the code and/or other readable information preferably is removed from the lock after the recoding operation. The lock is coded by help of input of information and brought to accept recoding to any code member in a series of code members and is valid until a new, previously not utilized code member in this series is introduced whereupon the lock is automatically recoded to this new code so that the previously employed code member(s) are no longer accepted. The lock is then recoded to accept a new code series by employment of a new appropriately coded recoding member which contains readable information about the code(s) of the different code members in the new series. The potentially valid code series are stored in a memory unit in the lock.

Abstract: A woodburning stove, fireplace, or the like which includes a hearth in a chamber with a flue outlet at a top thereof and a closeable bottom plate provided in a bottom of the chamber. A further chamber is provided under the plate, with the further chamber being lined with a refractory material. The further chamber includes a flue outlet duct to the upper chamber communicating at a rear end thereof so that flue from the fuel fired in the further chamber is substantially entirely combusted, with the combustion temperature being high and the combustion time for a given fuel supply in the further chamber being considerably longer as compared to the same amount of fuel in, for example, a conventional heating stove.

Abstract: The invention relates to a valve apparatus for evacuating and/or filling a refrigeration system having a hermatically closeable connecting tube. The apparatus includes a piston and cylinder unit which has a central passage for receiving such a connecting tube and is pressure operable to squeeze a sealing ring into sealing engagement with the tube to facilitate the subsequent filling or evacuating of the system through the tube via valving located in a valve block connected to the piston.

Abstract: A method of removing acid gases from hot flue gases wherein the flue gas is fed through a pipe (3) and up through a tubular reaction chamber (1) having a diverging bottom wall (2) which causes a rapid reduction in axial velocity. Further flue gas is introduced tangentially through a pipe (5) to produce a rising swirling stream of flue gas, in which a powdery absorption agent, that has been introduced through an inlet (4), is entrained. The agent reacts with the acid gas to produce powdery reaction products which are subsequently removed in separators (7,7').

Abstract: The invention relates to a pneumatic setting device having oppositely operable magnetic valves for alternately pressurizing and exhausting expansible chambers formed by one or more diaphragms to which a reciprocatable setting element is attached. In this construction a return spring may be omitted.

Abstract: Method and apparatus for ultrasonic blood flow velocity measurement based upon the doppler principle (doppler measurement), combined with simultaneous echo amplitude imaging by employing ultrasonic pulses (echo imaging). The method is used for investigation of living biological structures, in particular during movement, for example a heart function. The main application will be in hospitals and the like. The doppler measurement and the echo imaging is effected sequentially with so short intervals that the echo imaging is updated with a sufficiently high rate for obtaining an acceptable picture quality, with the doppler measurement occupying a substantial portion of the time. The information is presented in real time on a display screen. A control unit synchronizes the doppler measurement and the echo imaging, and there is incorporated one or more transducers in the equipment.

Abstract: A novel debranching enzyme product with properties in terms of thermostability and pH-optimum comparable to those of glucoamylase is produced by cultivating a strain belonging to the novel taxonomic group Bacillus acidopullulyticus. The novel debranching enzyme is used in conjunction with known saccharifying enzymes for the hydrolysis of starch.

Abstract: Hot waste gas is desulfurized in a spray drying-absorption process performed in an absorption chamber wherein a fluidized layer of partially reacted absorbent is maintained in the bottom area. Improved conditions are obtained for the reaction between absorbent and sulfur oxides in the waste gas, whereby the use of inexpensive absorbents of relatively low reactivity, such as limestone, comes into consideration.

Abstract: In the delignification of chemical wood pulp with oxygen and alkali a larger reduction of the kappa number may be obtained without an increase in the charge of oxygen or alkali, provided the pulp is pretreated with a solution of sulphite or bisulphite in order to introduce hydrophilic groups in the sulphate lignin in the chemical wood pulp.

Abstract: A process for increasing the capacity of plants for membrane filtration of milk or milk products, whereby prior to the membrane filtration, the milk or milk product is usually subjected to one or more pretreatments selected from the following:(a) heat treatment for bacteriological reasons,(b) fat standardization in view of the fat content of the product,(c) homogenization in view of the physical and organoleptic properties of the end product, and(d) pre-acidulation in order to influence the solubility of the ash components of the milk.According to this process, prior to the membrane filtration, said milk or milk product is additionally subjected to an enzymatic treatment with curdling enzyme under agitation of the milk or milk product to form an integrated dispersion of a coagel in whey. The resulting concentrate may be used as feeding additive or feeding starting material as well as a nutritive medium by microbial processes.

Abstract: The invention relates to a hydrostatic steering device having a servomotor connectable to wheels to be steered. The travel limits of the servomotor are sensed with position sensors which function to operate a locking apparatus which mechanically prevents further turning of the steering wheel upon a travel limit being reached in either direction.

Abstract: A rail insulator (5) for the securing of a conductor rail (2) on a rail support (4) which comprises a substantially U-shaped supporting rail in which holes are provided at regular intervals, preferably in two parallel rows, and where the rail insulator (5) is formed with a notch (18) corresponding to the thickness of the rail being used, is arranged so that on the side turning away from the notch it has outwardly-extending, hook-formed holding elements (24, 25) arranged to grip around and be secured to the rail support (4), in that between the holding elements there is provided a guide stud (30) which fits down into one of the holes in one of the rows of holes. One thus obtains a rail insulator which is well-suited for use in the building up of rail areas, in that the rail insulator can quickly and easily be removed and mounted on the rail support without detracting from the strength and the ability of the rail area to absorb mechanical forces from changes in current.

Abstract: A method and an apparatus for calcining pulverulent raw material, in particular cement raw meal, wherein the material is calcined suspended in a stream of hot gas in a calcining zone (4) in an overheated atmosphere by burning fuel in a stream of oxygen-containing gas in the zone, and precipitated in a precipitation zone (9). The rate of combustion of the fuel is accelerated by maintaining a temperature within the range 900.degree.-1250.degree. C. in the calcining zone by dividing the raw material into two streams (22',22) introducing and calcining only the first stream of material (22') in the calcination chamber (4). The temperature of the hot suspension withdrawn from the calcining zone is reduced by 100.degree.-300.degree. C. to a level within the range 800.degree.-1000.degree. C. by suspending the second stream of material (22) in the hot suspension during withdrawal thereof from the calcination chamber (4) and before the calcined material is precipitated in the precipitator (9).

Abstract: This invention relates to a fluid pressure operated tool of the type having an axially reciprocatable and rotatable shaft to which a work piece such as a rock drill is attachable. The tool is driven by a planetary piston type of motor with a rotary externally toothed gear member having rotational and orbital movement relative to a surrounding internally toothed gear member. The externally toothed gear member is connected to a rotatable valve member and reciprocatable and rotatable output shaft by a cardan type shaft. The output shaft has a piston part which is subject to being alternately pressurized in opposite directions to produce the reciprocating motion.

Abstract: The invention relates to a hydrostatic steering control device of the type having two motor ports connectable to a servomotor and a metering unit for metering the flow of fluid to or from the servomotor in accordance with the rotational movement of a steering wheel for operating the control device. The invention is directed to a way of balancing the distributing valve of the control device by subjecting opposite sides thereof to high and intermediate pressure zones and providing a throttle gap between the high and intermediate pressure zones an a second oppositely acting throttle gap between the intermediate pressure zone and a third zone of lower pressure.

Abstract: The invention relates to an apparatus for conveying liquids of which the vapor pressure is above atmospheric at ambient temperatures from a storage container to a delivery point, particularly for dispensing refrigerant.