Abstract: A method of producing potassium sulfate consists in conversion of sodium sulfate with potassium chloride in an aqueous medium to yield glaserite and a glaserite solution. Then, the glaserite is decomposed with potassium chloride in water to obtain potassium sulfate and a sulfate solution which is returned to the first stage of conversion. The glaserite solution is cooled at temperatures ranging from +3.degree. to -8.degree. C., whereby mirabilite and a chloride solution are formed, the latter being evaporated to obtain sodium chloride and a concentrated chloride solution. Finally, the concentrated chloride solution is mixed with mirabilite, and the resulting suspension is delivered to the first stage of conversion of sodium sulfate with potassium chloride. The proposed method permits producing high-quality potassium sulfate with full utilization of the return solutions. The yield of potassium sulfate reaches 98.6% at a K.sub.2 O content of up to 53% by weight.

Abstract: The continuous treatment of a cellulosic material in the form of chips to produce at least partial delignification of the material without true mechanical grinding is effected in apparatus comprising two parallel meshing screws which are rotated in the same direction in a sheath and have identical threads providing a plurality of zones of different pitch. The material is passed in succession through a first zone for feeding the material downstream, a first braking zone for causing a first compression of the material, a second zone for feeding the material downstream and in which the material is brought into contact with a reagent, e.g. steam or a chemical reagent, and a second braking zone for causing a second compression of the material.

Abstract: A biologically active substance is incorporated in a unitary body with a magnetically responsive material for carrying out diffusion testing. These may be, microbiological, immunological, serological and other biochemical examinations. The body is applied against a substrate or medium by application of an external magnetic field and a reaction region is produced at the site of the body and is measured by means of a reader. In order to insure deposit of the body on the substrate a predetermined location and corresponding reading of the reaction region at such location, the support for the substrate and the dispenser and reader are provided with suitable releasable coupling and orienting devices such that the dispenser and reader can be respectively engaged and oriented on the support in predetermined secured positions.

Abstract: Apparatus for cutting and simultaneously dispensing a web of roll material comprising a carrier for a roll of material mounted in a casing and urged against a rotatable drum which is driven in rotation by manual traction applied to a free end of the material extending from the casing. A profiled pawl is supported at one of the ends of the drum and cooperates with a shock absorber and an elastic abutment to brake the drum at the end of one revolution and hold it in readiness for a subsequent pull on the material. An eccentric lever is secured at the other end of the drum and is engaged by a spring such that in a first portion of rotation of the drum, the spring absorbs energy and after a dead point, it releases its energy to drive the drum in rotation.

Abstract: A dental handpiece in which an elongated handle sleeve is transversely divided by formation of an anterior sleeve showing a receptacle for a drivable dental-treatment instrument. A connected grip sleeve is detachable by a rotatable tightening ring. The handle sleeve has a coolant line running at least in the area of the transverse space within the inside of the sleeve outside the longitudinal axis of the handle sleeve, the coolant line is also transversely divided and leads to the area of the dental-treatment instrument. Two front sides of the anterior sleeve and the grip sleeve have both two front sides facing each other. One front side is provided with a projecting connecting piece for the cooling line and the other front side is provided with a connecting socket for an insertable connecting piece.

Abstract: In the low pressure casting of a metal in a mould supplied from below by an electromagnetic pump, the durations of the various stages of the moulding cycle are determined in dependence on the temperature of the mould, the temperature of the metal in the mould and the temperature of the metal in the furnace to obtain optimum casting conditions despite variations in these temperatures.

Abstract: A bus arranged in accordance with the present invention permits the boarding level to be minimized at bus stops without unduly reducing the ground clearance to be maintained during operation. When supporting struts are being extended at a bus stop, the bus will tilt forward about a horizontal transverse axis extending through these supporting points, so that the distance between the bus body and the roadway will considerably decrease in the forward portion of the bus. Short-circuiting the air suspension bellows of front and rear axles prevents the air bellows from countering the down-movement of the bus body with a restoring force. When passengers have boarded, the bus is restored to its horizontal position by retracting the supporting struts, with the air from the air bellows of the rear axle flowing back to the front axle.

Abstract: A fire control device for sighting a gun by introducing, between the axis of the gun and the direction of the target, an angular shift based on the trajectory of the ammunition, the device comprises a sighting telescope in which an image of fire crosswires defining a line of collimation are visible and means for moving the fire crosswires in dependance on a signal from a rangefinder of the laser type which includes a first collimator comprising an objective and crosswires for sighting the rangefinder and an image of which can be seen in the telescope, and a second collimator for shifting the line of collimation which comprises an objective and the fire crosswires which are placed at the focal point of the objective, the second collimator being associated with an optical reflecting element for reflecting the image of the fire crosswires into the telescope and the two collimators are arranged so that the image of the sighting crosswires passes through the optical reflecting element and is reflected by the fire

Abstract: A pull strand of high tensile strength which may be composed of a number of parallel, longitudinal steel wires and a series of transverse, stiffener elements made of aluminum or other metal spaced along the pull strand and providing oppositely facing lateral edges for active engagement with coned sheaves are interconnected solely by a continuous molded body of rubber or rubberoid material in adherence with the pull strand and with the transverse elements. The molded body runs longitudinally through identical cavities of the said transverse elements, extending sidewardly at least onto their lateral edges and filling intermediately thereto at least a portion of each space between the sidewalls of the said transverse elements along the said cavities.

Abstract: Honeycomb muffle in tank furnaces for glass melting, comprising blocks of refractory material, characterized in that at least the crown of each furnace is made of blocks of refractory material, the free surface of which facing inwardly of the furnace is shaped with at least one recess defined by projecting ribs.

Abstract: A planting box having a frame which consists of a plurality of vertical walls and being of polygonal cross-section is provided with vertical channels and vertical ribs. The channels and ribs are complementary in their cross-section. Ribs of one planting box fit into the recesses of another identical planting box, so that a planting arrangement can be erected which consists of a plurality of inter-connected identical boxes. In each channel of the planting boxes supporting shoulders are formed which support the ribs of a laterally adjacent planting box, so that each box is vertically offset with respect to any laterally adjacent box by half of the box height.

Abstract: Apparatus for use in positioning a unit successively relative to a plurality of tubes of a regular array of tubes supported by a tube-plate within an enclosure provided with an access opening, e.g. relative to the boiler tubes of a steam generator of a nuclear power station, as described in U.S. Pat. No. 4,004,698 is adapted for association with transporting apparatus for placing the positioning apparatus in the enclosure, the transporting apparatus comprising a rectilinear guide rod for passing through the access opening and for guiding a carriage provided with a coupling assembly for releasably coupling the positioning apparatus to the carriage during movement thereof between the outside and the inside of the enclosure and which are disconnectable to permit movement of the positioning apparatus across the tube-plate.

Abstract: A safety arrangement for diesel engines to respond to an abnormal change of the ratio of the useful torque delivered by the diesel engine and the fuel quantity per power stroke. The latter is defined by the position of control rod of the injection pump. A transducer converts the control rod displacement into a mechanical or electrical control variable which is at least approximately proportional to the fuel quantity per power stroke. The control rod displacement is converted by a crank drive into a rotation of a correcting element, and the ratio of connecting rod length to crank radius is in the range between 6:1 and 8:1. The rotation angle of the correcting element is less than 90.degree. in the range between zero and full useful torque. The rotation angle range on either side of the crank position is 90.degree.. An electrical control variable may be generated by a transducer which is free of contacts and supplies a direct current signal proportional to the rotation angle of the correcting element.

Abstract: A method according to the present invention is intended for treating items (articles) for magnetically soft alloys employed in radio-electronic, relay and switching apparatus, in optical-and-mechanical and automation systems. The method consists in saturating the surface of items with chromium inside a powder chromizing mixture at a temperature in excess of 800.degree. C. The items are heated at a rate not higher than that of recrystallization of a metal of the items, and the rate of diffusion processes of saturating the items. The items are cooled at a rate close to that of phase transformations and formation of a magnetic structure in the metal of the items, for example, at the rate of 20-200 degree/hour below the Curie point. To enhance the magnetic properties and the stability thereof, as well as wearability and the resistance of the items to corrosion, chromizing of the item surfaces is conducted in an inert gas atmosphere.

Abstract: A dental handpiece comprising a holding sleeve, a head sleeve inclined to the holding sleeve and adapted to mount a dental instrument, a connecting zone providing an interconnection between the holding sleeve and the head sleeve, a drive shaft housed mainly within the holding sleeve and a driven shaft housed within the head sleeve, and a ball-type planetary transmission housed within the connecting zone and serving to transmit drive between the drive shaft and the driven shaft. The drive shaft is sub-divided into a first shaft portion which is housed in the holding sleeve, and a second shaft portion which is housed within the connecting zone and coupled with the planetary transmission. The second shaft portion extends coaxially with the driven shaft in the head sleeve, and the first and second drive shaft portions are coupled together by a rotary-drive-transmitting coupling.

Abstract: A seal ring with tapered surfaces is constituted by an inner ring, outer ring and a tightening resilient member. Each of the inner and outer rings is provided with an inner and outer peripheral surfaces and a pair of sealing end surfaces extending between the inner and outer peripheral surfaces. Each of the inner and outer ring is divided in the circumferential direction into two sections. The inner peripheral surface of the outer ring fits the outer peripheral surface of the inner ring, while the outer peripheral surface of the outer ring is surrounded by the resilient member so that the inner and outer rings are resiliently pressed radially inwardly. The end surfaces of the inner and outer rings are arranged flush to form common sealing surfaces. At least one of the common sealing surfaces thus formed constitutes a conical surface so that the axial distance between two common sealing surfaces is varied such that it increases toward the radially outer side.

Abstract: A machine for drilling and routing of printed circuit boards comprises a support mechanism for supporting a stack of superimposed boards in a support plane and for moving the stack of boards in a first predetermined direction parallel to the support plane. A tool spindle is disposed above the stack of boards and is movable in a second direction parallel to the support plane and perpendicular to the first direction, so that the positions of the holes to be drilled in the PC-boards can be determined in a coordinate system having the first and second directions as its X-axis and Y-axis respectively. For holding the stack of PC-boards pressed together during the drilling or routing operation, the machine comprises press rollers, which exert a pressure force upon the stack of PC-boards towards the support mechanism. The press rollers are arranged on both sides of the tool spindle with their axes of rotation parallel to the direction in which the tool spindle can be moved, i.e. the Y-direction.

Abstract: The electroinsulating material of the present invention contains a fluorine rubber, low-molecular weight sticky resin, cross-linking agents, particles of a mica-containing material, and a mineral filler.This material features high corona resistance, elasticity, heat resistance, and incombustibility.

Abstract: A sealing device especially designed for sealing between the opposed flat surfaces of a stationary member and a rotary member. The device comprises a multiple seal ring composed of a plurality of annular seal elements of different diameter which are received in an annular groove formed in the rotary member. The seal elements each have a flat sealing face formed at one end for sealing contact with said flat surface of said stationary member and a conical sealing face formed at the other end for sealing contact with a conical bottom surface of the groove, the conical sealing face diverging in a radially outward direction toward the flat sealing face. The seal elements are each cut radially so as to provide themselves with a radially outwardly expanding force and closely fitted one over the other in a concentric relation with the radial cut portions of the respective seal elements being circumferentially displaced from one another for sealing the cut portions of the seal elements.

Abstract: A device for cutting sound grooves in a disc recording medium has a cutting stylus for recording sound by cutting on the disc recording medium. The cutting stylus comprises a cutting stylus structure of diamond having a cutting part for cutting the disc recording medium while producing a cut chip therefrom. A surface of the cutting stylus structure contacts the chip having been rendered electroconductive to a specific depth by an ion-implantation process.