4801 4805.output

* GB785208 (A)

Description: GB785208 (A) ? 1957-10-23

Sound-insulating boards

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The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

PATENT SPECIFICATION Inventor: ANDERS EINAR ANDERLIND 785208 Date of Application and filing Complete Specification: June 11, I 1956. ? E No18022/56 Patent of Addition to No 736755 dated Oct 6, 1953. Complete Specification Published: Oct 23, 1957. Index at acceptance:-Class 96, B( 1: 2 A: 15: 19: 20). International Classification:-D 21. COMPLETE SPECIFICATION Sound-Insulating Boards We, AKTIEBOLAGET SCHAWNS SONER, a Swedish Joint-Stock Company, of Klemensnis, Sweden, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: - The present invention relates to sound insulating boards which are formed from fibrous or like material and are provided with a plurality of holes in the face surface thereof In these boards the holes are usually placed symmetrically over the complete surface and spaced evenly from each other whereby an overall, uniform pattern is obtained when a number of boards are placed adjacent to each other, on a wall or ceiling of a room Sometimes the holes are placed at random over the surface of the boards whereby an irregular overall pattern is obtained.

There is described and claimed in Specification No 736,755 a sound insulating board which comprises at least two groups of holes arranged in such a manner that a decorative pattern is formed when several boards are placed adjacent to each other. According to the present invention a sound insulating board is provided with a face surface in part of which is formed one group of holes the other part or parts of said surface being plain, whereby a decorative pattern is formed when several boards are placed adjacent to each other The holes of the group lPrice 3 s 6 d l may be all of the same or of different dia 35 meter, evenly spaced from each other or spaced at random. The group of holes may have any desired outline and may be positioned in any part of the face surface of the board, for example 40 the groups may define a circle or square in the centre of the board, a square or triangle in one corner of the board, or a stripe extending across the board diagonally or otherwise It will be appreciated that innumer 45 able ornamental and decorative overall patterns may be obtained by placing a number of boards adjacent to each other The individual boards which compositely make up an overall pattern may be identical with or 50 different from each other and furthermore the boards of the present invention may be used in conjunction with the boards as described in Specification No 736,755 to give a desired pattern 55

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* GB785209 (A)

Description: GB785209 (A) ? 1957-10-23

Manufacture of 1:1-difluoro-1-chlorethane

Description of GB785209 (A)

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DE1002303 (B) FR1151291 (A) DE1002303 (B) FR1151291 (A) less Translate this text into Tooltip



COMPLETE SPECIFICATION. Manuacture sf: Difluoro-l-Chlorethane. We, FARBWERKE HOECHST AKTIEN GESELLSCHAFT vormals Meister Lucius & Bruning, a body corporate recognised under German law, of Frankfurt (M)-Hoechst, Germany, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: It is known to chlorinate l:l-difluorethane at about 80" C. to about 120 C. in the gaseous phase with exposure to light. A yield of somewhat more than 70 per cent of 1: 1-difluoro- l-chlorethane is obtained under the most favourable conditions. A little more than 20 per cent of the starting material remains unchanged and about 5 per cent of the starting material is converted into more highly chlorinated products. It has also been proposed to react 1: lidifluor- ethane in the gaseous phase with chlorine at a temperature ranging from room temperature up to 300 C. with exposure to light, to form 1: l-difluoro-l-chlorethane, which is then further chlorinated at a temperature above 300" C. In the first stage of this process, 1: l-difluoroXl-chlorethane is obtained in a total yield of about 60 per cent. However, about 15 to about 20 per cent of the reacted product is converted into more highly chlorinated products. In this reaction the yield is therefore about 70 per cent. Accordingly, this process as compared with that referred to above has the further disadvantage that a considerably larger amount of by-products is formed and an even smaller yield is obtained.

The compound 1:1-difluoro-1-chlorethane is useful as a refrigerant, but is especially valuable as an intermediate. Thus, it can be dehydrochlorinated, usually by pyrolysis, to produce vinylidene fluoride, which can be polymerized alone or copolymerized, for example, with trifluorochlorethylene to produce a variety of valuable products. The present invention is based on the observation that the chlorination of 1:1difluorethane with exposure to light, for example, ultra-violet light, can be carried out in the liquid phase. In this case practically no undesired side reactions occur. Favourable factors are the lower reaction temperatures which can be attained, and the diluting action of the components of the reaction. It is immaterial in what manner the liquid phase is obtained. If it is obtained by cooling the 1: 1-difluorethane below its boiling point (24 C.), it is unnecessary to work under pressure, and the chlorination can be carried out at correspondingly higher temperature but below the critical temperature. Finally, the chlorination may be carried out in a suitable solvent which forms the liquid phase, and the pressure and temperature can be varied within a wide range. As solvents there are suitable halogenated hydrocarbons which are not chlorinated under the reaction conditions, such as carbon tetrachloride or 1: l-difluoro-l-chlorethane. In each of these cases, the chlorination can be carried out in a continuous manner. When the chlorine tion is carried out in accordance with the invention under these conditions, the reaction almost ceases when the quantity of chlorine calculated for the formation of 1: 1-diftuoro-l-chlorethane has been consumed, and very pure 1: 1-difluoro-1-chlorethane boiling at -23 to --23.70 C. is obtained in a yield exceeding 90 per cent. As compared with the known processes which are carried out in the gaseous phase, the process of this invention which is conducted in the liquid phase has the advantage of producing a considerably larger yield coupled with a considerably smaller quantity of more highly chlorinated products. Furthermore, chlorination in the liquid phase, as compared with chlorination in the gaseous phase, has the further advantage that the yield per unit of volume and time is greater. Furthermore, the removal of the hydrogen chloride formed is considerably simpler than in the known processes, since - in the process of this invention the hydrogen chloride escapes in gaseous form and can be removed to a great extent by distillation.

In contradistinction thereto, in the known processes which are conducted in the gaseous phase the hydrogen chloride is removed by washing with water and thereby lost. Although it is known to carry out the photochemical chlorination of normally gaseous halogenated hydrocarbons other than 1: 1-difluorethane in the liquid phase, it could not be expected that it would be possible to chlorinate 1: 1-difluorethane in the liquid phase to form almost exclusively 1: l-difluoro-l-chlorethane, especially as it is known that the chlorination of the analog ous 1: 1-dichlorethane in the liquid phase a mixture of 1:1:1- and 1: 1: 2-trichlorethane is formed, whereas in the gaseous phase practically only 1:1: l-trichlorethane is obtained. It would, therefore, have been expected that in the chlorination of 1:1 difluorethane in the liquid phase, i.e. at a temperature lower than that used in the known processes, a mixture of 1: l-difluoro- 2-chlorethane and 1: l-difluoro-l-chlor ethane would be obtained. The following Examples illustrate the invention EXAMPLE 1. 1660 grams of 1: 1-difluorethane were condensed in a chlorination vessel provided with an irradiation lamp, using reflux con densation with dry ice/butanol. Chlorine was introduced while irradiating the mixture and the hydrogen chloride escaped at the top. When 1790 grams of chlorine had been absorbed the chlorination practically ceased. The produce was washed, dried, and fractionally distilled. There were obtained 145 grams of 1: 1-difluorethane, 2200 grams 1:1- difluoro -1- chlorethane (which, after deducting the quantity of starting product, corresponds to a yield of 96%) and 175 grams of over-chlorinated higher boiling constituents. By introducing the chlorine and the 1: l-difluorethane at

the bottom of the vessel in the ratio 1:1, the 1: l-difluoro-l-chlorethane can be con tinuously withdrawn by means of an over flow pipe. EXAMPLE 2. 2.5 kilograms of 1: 1-difluorethane were condensed in a lead-lined pressure vessel provided with a reflux condenser and an irradiation lamp. The temperature was maintained at 05 C. to 10 C. by cooling with brine. While irradiating with ultraviolet light chlorine was forced in under pressure at the rate at which decolorisation occurs. When 2.7 kilograms of chlorine had been absorbed the chlorination was practically finished. The pressure rose to 18 atmospheres at --5" C. The gaseous mixture was washed, dried and distilled. There were obtained 3.28 kilograms of l:l-difluoro- l-chlorethane in addition to 217 grams of the starting material and 260 grams of overchlorinated constituents. The yield, after deducting quantity of starting material, was 98%. If, after termination of the above operation, additional quantities of chlorine and 1: 1-difluorethane are introduced in the ratio of 1:1 under pressure into the 1:1difluoro-l-chlorethane formed, and the reaction product is removed from the liquid phase by means of a valve and the hydrogen chloride is separately removed from the gaseous phase by releasing the pressure, the process becomes continuous. EXAMPLE 3. Two litres of carbon tetrachloride were charged into a chlorination vessel provided with a water cooling coil and an irradiation lamp. 1: 1-difluorethane and chlorine in a molar ratio of 1:1 were introduced separately, while irradiating and cooling the mixture to 10 C. In this manner, 850 grams of l:l-difluorethane and 912 grams of chlorine were introduced in the course of eight hours. The escaping reaction gases, and the carbon tetrachloride entrained in proportion to its vapour pressure, were washed with water, dried over calcium chloride, and distilled. There were obtained 110 grams of starting material and 1045 grams of 1: l-difluoro-l-chlorethane, corresponding to a yield of gf0O. The residue consisted of the entrained carbon tetrachloride and over-chlorinated constituents. What we claim is : - 1. A process for the manufacture of 1: l-difluoro-l-chlorethane, wherein 1:1difluorethane is reacted in liquid phase with chlorine with exposure to light. 2. A process as claimed in Claim 1, wherein the 1:1 -difluorethane is maintained in the liquid phase by cooling. 3. A process as claimed in Claim 1 or 2, wherein the reaction is

carried out at a temperature below about --34" C. and under atmospheric pressure. 4. A process as claimed in Claim 1 or 2, wherein the reaction is carried out under a pressure sufficient to maintain the 1: l-difluorethane in the liquid phase. 5. A process as claimed in any one of Claims 1 to 4 wherein the liquid phase is formed by an inert solvent. 6. A process as claimed in Claim 5,

* GB785210 (A)

Description: GB785210 (A) ? 1957-10-23

Combustion chambers


We, POWER JETS (RESEARCH AND DEVELOPMENT) LIMITED, a British Company, of 25 Green Street, London, W 1, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: - In a combustion system for continuously burning fuel in a stream of air, such as for example, that of a continuous combustion turbine plant, or that of some form of aircraft jet-propulsion plant employing a gas turbine or a ram jet system, the incoming air is often divided into two or more separate main streams, at least one of which is for initiating and supporting combustion while at least one other may for example be for diluting the hot combustion products with cooler air In such combustion systems where the air flow is divided into two or more main streams, it may be desirable to have means operable, on occasion, to vary the distribution of air between these streams There are difficulties in designing valves for this purpose which will operate satisfactorily and consistently at the high temperatures prevailing in the neighbourhood of the combustion zone. According to the invention, the distribution of air between streams in a combustion chamber is varied by injecting into a main stream a

supply of controlling air under pressure in a sense tending to divert the main flow from one stream to the other. The invention is illustrated by the drawing accompanying the Provisional Specification, showing a combustion chamber partly in axial section. The combustion system and burner arrangement indicated in the drawing is of the common form comprising a combustion chamber 1 and, inside the combustion chamlPrice 7 W 55210 ber, a flame tube 2 which encloses the actual combustion space Compressed air flows into the space within the chamber 1 and around the outside of the flame tube 2: however, a stream of some of this air, as combustion air, enters the upstream end of the flame tube 2 The liquid fuel injector 4, and its supply pipe 5, which is connected to the source of fuel, are located within the tube 2 at or adjacent to this up-stream end. Slightly downstream of this is the igniting means 6 The chamber is a cylinder 1 reduced at one end at which it is open to admit a stream of air, and closed at the other The flame tube 2 is cylindrical and mounted coaxially within the combustion chamber 1 but spaced apart from the inner wall of the chamber, it is open at each end for the passage of the air stream, and has its inlet end adjacent to but somewhat downstream of the inlet end of the chamber 1 The tube 2 at its downstream end extends through the closure wall of the closed end of the chamber 1 The open inlet end of the combustion chamber is connected to receive the supply of air under pressure-i e the air from the compressor in a gas turbine plant or the ram air in a ram jet plant Usually the air will be flowing at a flame-extinguishing velocity and accordingly some means are provided for maintaining a stable zone of combustion inside the tube 2, into which zone the fuel is injected and ignited This is shown as a closure 3 extending across the flame tube 2 but admitting air through swirl ports to set up a helical vortex, the stable zone of combustion being within the core of this vortex, in well-known manner The injector 4 is located to inject the fuel into the stable zone Downstream of the closure 3 the flame tube wall is pierced by a succession of further rings of ports 2 a, for admitting the rest of the air as further combustion r 7 PATENT SPECFICATION Inventor: -PETER MARTIN. Date of filing Complete Specification: March 22, 1955. Application Date: April 1, 1954 No 9563154. Complete Specification Published: Oct 23, 1957. Index at Acceptance:-Class 51 ( 1), Al B 1 A. International Classification:-F 23 d. COMPLETE SPECIFICATION. Combustion Chambers. 785,210 air or as dilution air mixing with the combustion products.

The invention is concerned with providing means-operable at will and possibly partly automatically controlled according to ambient atmospheric pressure-for varying the distribution of the incoming air by reducing the proportion of the air which enters the upstream end of the flame tube 2 as combustion air, relatively to that which flows between the tube 2 and the walls of the chamber 1, to enter the tube by the ports 2 a. These are operable to supply a small auxiliary control jet of compressed air to the neighbourhood of the upstream inlet to the flame tube 2 in a sense tending to oppose the entry of combustion air and accordingly to divert some of this air to the down-stream entry ports 2 a The control jet issues as an annular sheet of air from an annular slit. The control-air line enters the flame tube transversely through a streamlined tubular member 8 similar to fuel-tube 5, and which connects through a right-angled bend with the hollow body 7 lying along the axis of the flame tube 2 and chamber 1; this body 7 has an open end terminating in substantially the same plane as the inlet end of the flame tube 2, and a closed end nearer to the closure 3 Screwed into the wall of the closed end and extending along the axis of the body 7 with annular space around is a stem 9 terminating in a head 9 a outside the body 7 and close to the end of the wall of the body so that between them they form a shallow annular slit 7 b Air can issue from this slit as an annular sheet either radially in the plane of the inlet edge of the flame tube or preferably, as shown, partly in this plane btfff with a component directed upstream relatively to the main stream of air The end of the body 7 and the underside of the head 9 a are both conical but of different angles so that the issuing air has an upstream component and the gap between head and body decreases radially outwardly so that the air passage is either of constant area or convergent. In operation, the main stream of air, at} which may be supplied by a main compressor (driven, for example, by a gas turbine operated by the combustion products issuing from the flame tube), enters the combustion chamber 1, travels a short distance up to the -56 inlet end of the flame tube 2 and then divides, as shown by the arrows One branch of the stream enters the flame tube as combustion air; the second branch flows along 'the chamber, outside the flame tube, C)C which it eventually enters through the ports 2 a as additional or diluent air Control air can be supplied to the interior of tube 8 and body 7 from, for example, an auxiliary compressor or from the main compressor S.3 and a booster compressor, by opening a control valve, whereupon a small annular air jet issues from body 7, crossing the first main air stream branch transversely where this stream is

entering the flame tube; accordingly part of this branch of the stream 70 is diverted into the second branch and flows around the outside of the flame tube 2 to the downstream ports 2 a The flow of control air required for this action is small The supply of this air may be controlled by a 75 barometric device so as to effect diversion at high altitudes, or the control may be in accordance with the temperature in some part of the combustion chamber or may be by the turbine speed governor or by some 80 other means, according to the purpose for which the distribution of air streams within the combustion chamber is being varied. Thus in Patent No 662,434 one stream of air is preheated by flowing between the flame 85 tube and an enveloping jacket, fuel being introduced into the air in this space for vaporisation before the air-fuel mixture enters the flame tube, and a valve, which may be thermostatically controlled, can W vary the air distribution, the present invention can be applied to such an arrangement, the supply of air for effecting diversion being possibly thermostatically controlled.


* GB785211 (A)

Description: GB785211 (A) ? 1957-10-23

A method of extracting cellulose from cellulosic raw material


A high quality text as facsimile in your desired language may be available amongst the following family members:

CH317139 (A) DE1039351 (B) FR1086213 (A) NL182089 (C) CH317139 (A) DE1039351 (B) FR1086213 (A) NL182089 (C) less

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-PATENT SPECIFICATION Date of Application and filing Complete Specification: Nov 5, 1953 No 30683-13. Application made in Belgium on Nov 5, 1952. Complete Specification Published: Oct 23, 1957. Index at Acceptance -Class 2 ( 2), W( 1: 2: X). International Classification:-D 2 lc. COMPLETE SPECIFICATION. A Method of Extracting Cellulose from Cellulosic Raw Material. I, THEOPHILE ISIDORE SOPHIE VERMEIREN, of 48 Avenue Joseph Verboven, DeurneAnvers, Belgium, of Belgium nationality, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement:- The invention relates to a method of exlo tracting cellulose from cellulosic raw material, in which an extracting liquid is utilised for the removal from the cellulosic raw material of the resin and like extractible substances. In known processes of this kind extracting liquids in the form of an acid, calcium, magnesium or ammonium bisulphite solution or solution of an alkali, may be used. The invention has among its objects to improve known processes so as to provide a higher efficiency as well as to improve the quality of the resultant product.


* GB785212 (A)

Description: GB785212 (A) ? 1957-10-23

Improvements relating to electromagnetic field-controlling devices


COMPLETE SPECIFICATION Improvements relating to Electromagnetic Field-Controlling Devices We, FERRANTI LIMITED, a Company registered under the Laws of Great Britain, of Hollinwood, in the County of Lancaster, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to electromagnetic accelerometers, an object being to provide an accelerometer of improved sensitivity. In accordance with the invention an accelerometer comprises two magnetic circuits having a common airgap, means for setting up an alternating field in each of said circuits, a short-circuited coil weighted so as to have substantial mechanical inertia and supported so that a part only of the coil is adapted to move against spring action across the common field in the airgap in such manner as to vary the relative effective reluctances of said magnetic circuits, and response means for deriving a signal dependent on the relative value of said reluctances. Said coil may be mounted at one end of an elastically flexible support which supplies said spring action, the other end, of the support being fixed relative to the magnetic circuits. Said response means may include two windings located respectively on parts of said magnetic circuits that are not in common, means being provided for deriving said signal from the difference between the voltages across said windings. The accompanying drawing is a simplified and partly diagrammatic view in perspective of one embodiment of the invention. In carrying out the invention according to one form by way of example, an accelerometer consists of a stack 10 of E stampings 11 of suitable magnetic material. The free ends 121 of the outer limbs 12 are bridged

by a yoke 13 of straight stampings 14 which lies within the same pair of parallel planes that contains the E stampings 11. The inner limb 15 is shorter thall the outer limbs, thereby providing an airgap 16 between the end face 15' of the inner limb and a central portion of the bridging yoke 13. Two magnetic circuits are thus formed. Each includes an outer limb 12 and a part of the yoke 13, the inner limb 15 and the airgap 16 being common to both. Inner limb 15 carries a primary winding 17 arranged to be energised by alternating current over leads 171 from a source not shown. Each outer limb carries a secondary winding 18; these two windings are connected in series opposition to provide an output at 18l; this is applied to a suitable instrument 24 which is arranged to respond, to the sense as well as to the extent of the applied signal. Loosely surrounding the bridging yoke 13 is a short-circuited coil 19 of one or more turns-conveniently, a single turn of copper. The turn is weighted in any convenient manner (not shown) so as to possess appreciable mechanical inertia. The turn is mounted at one end of an elastically flexible support in the form of a resilient rod 22 the other end 23 of which is fixed relative to the magnetic circuits so that the rod can flex in a plane parallel to the planes of the stampings. The turn 19 is thus able to move in the slightly curved directions indicated by the arrows, thereby causing a part ofthe turn to cross the common field in the airgap 16. In operation, the accelerometer is so located in the craft whose acceleration is to be indicated that the direction of motion of the craft is aligned with yoke 13, which thus lies in a fore-and-aft position. The primary winding 17 is energised, thereby setting up an alternating field in each magnetic circuit. The copper turn 19 behaves like shortcircuited secondary winding and so sets up a counteracting field in that portion of bridging yoke 13 embraced by it; the effective reluctance of this portion of the yoke is thereby so much increased that it forms in effect a boundary between the two magnetic circuits, the yoke being in effect divided at this portion into two parts (one on each side of the turn) which form parts of the respective magnetic circuits. When the turn is at the centre of the bridging yoke, and therefore in line with the centre of the gap 16, the flux from the end face inner limb 15 divides equally between the two parts of the yoke on either side of its centre; the effective reluctances of the two magnetic circuits are therefore equal, the output voltages of the two secondary windings 18 are equal, no signal is developed at 18l, and instrument 24 gives a zero indication. Any displacement of the turn 19 from the centre of the yoke 13 correspondingly displaces the effective boundary between the two

magnetic circuits, with the result that the bridging yoke and hence the field in the gap 16 become unequally divided between the two parts of the yoke and hence between the two magnetic circuits. The magnetic circuit which now includes the longer part of the yoke consequently receives more of the flux in the gap and hence has a less effective reluctance than the other magnetic circuit The output voltages accordingly cease to be equal and the difference between them provides a signal at 181 to be displayed by instrument 24. By thus controlling the distribution of the airgap field between the two magnetic circuit, the movement of the short-circuited turn or coil 19 controls their relative effective reluctances and hence the value of the indicated signal. When the craft is moving at a steady speed or is stationary, the spring force of the rod 22 maintains turn 19 in the central position. The reluctances of the magnetic circuits are thus equal, the output voltages from windings 18 balance one another, and instrument 24 gives a zero indication. As soon as the craft starts to accelerate, the inertia of turn 19 causes it to be displaced, against the spring action of rod 22, from the central position in a direction away from that of the craft's movement, the extent of displacement of the coil being dependent on the extent of the acceleration. An out-of-balance signal is thus developed at 181 and the acceleration is indicated by instrument 24 against a calibrated scale. When acceleration ceases, the elasticity of rod 22 restores the turn to the central position. Retardation of the craft causes the turn to be displaced in the other direction-i.e. in the direction of the craft's movement. The out-ofbalance is thus of the opposite sense and instrument 24 gives an appropriate indication. Conveniently, instrument 24 is of the centrezero kind, indicating accelerations on one side and retardations on the other side of the centre zero. The alternating field in the magnetic circuits may alternatively be provided by suitably energising the windings 18 in series, the primary winding 17 being dispensed with. A bridge circuit including windings 18 in two adjacent arms and fixed resistors in the other arms, may be used for this purpose. An accelerometer in accordance with the invention is found to be sensitive in operation, with particularly good linearity in the zero region, as well as being robust mechanically. What we claim is: - 1. An accelerometer comprising two magnetic circuits having a common airgap, means for setting up an alternating field in each of said

circuits, a short-circuited coil weighted so as to have substantial mechanical inertia and supported so that a part only of the coil is adapted to move against spring action across the common field in the airgap in such manner as to vary the relative effective reluctances of said magnetic circuits, and response means for deriving a signal dependent on the relative value of said reluctances. 2. An accelerometer as claimed in claim 1 wherein said coil is mounted at one end of an elastically flexible support which supplies said spring action, the other end of the support being fixed relative to the magnetic circuits. 3. An accelerometer as claimed in either of preceding claims wherein said response means includes two windings located respectively on parts of said magnetic circuits that are not in common, means being provided for deriving said signal from the difference between the voltages across said windings. 4. An accelerometer as claimed in any of the preceding claims wherein said means for setting up an alternating field includes means for energising by alternating current a primary winding carried by a part of said magnetic circuits which is in common. 5 An accelerometer as claimed in claim 3 wherein said means for setting up an alternating field includes means for energising by alternating current said two winding in series. 6. An accelerometer substantially as hereinbefore described with reference to the accompanying drawing.