5231 5235.output

* GB785638 (A)

Description: GB785638 (A) ? 1957-10-30

Consumable electrode arc melting apparatus

Description of GB785638 (A)

PATENT SPECIFICATION 785,638 ct Date of application and filing Complete Specification: Jan 27, 1956. No 2723/56. Application made in United States of America on Feb 21, 1955. Complete Specification Published: Oct 30, 1957. Index at acceptance-Classes 39 ( 3), H( 2 B 2: 3 A: 3 E 1); and 40 ( 3), A 5 FI. International Classification:-GO 8 c H 05 b. COMPLETE SPECIFICATION Consumable Electrode Arc Melting Apparatus We, TITANIUM METALS CORPORATION OF AMERICA, a Corporation organised under the laws of the State of Pennsylvania, United States of America, of 233 Broadway, New York, State of New York, United States of America, 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 consumable electrode arc melting apparatus and more particularly to means for indicating the progress of the melting operation in the arc furnace as it reduces the length of the consumable electrode. Consumable electrode arc melting furnaces are often employed to melt refractory metals such as titanium, zirconium and molybdenum In such furnaces an elongated electrode is formed of the metal to be melted, often by compression of powdered metal into a cohesive stick An arc maintained between the electrode of the metal being melted and metal in a subtended crucible gradually melts the electrode, the molten metal forming an ingot in the crucible During the melting operation the electrode is gradually lowered into the crucible to maintain desired arc conditions, being clamped at the top and connected thereby

to suitable mechanical lowering equipment The electrode is generally melted or consumed as completely as possible; however, the electrode should not be consumed or melted to a point too close to the clamps lest these and associated mechanical structures be also melted or at least affected by proximity to the heat of the arc. Therefore, the length of the residual end or stub of the electrode is a critical factor affecting efficiency of the melting operation and the life and maintenance of the equipment. Unfortunately the furnaces employed for arc melting are universally tightly enclosed so that the actual progress of the melting operation cannot be visually observed, and mechlPcn 3 s 6 d l anical devices for indicating remaining stub length have generally proved unreliable or inaccurate. It is therefore the object of this invention 50 to provide apparatus for indicating the length of a consumable electrode in an arc furnace. Another object of the invention is to provide apparatus to indicate when an electrode has been consumed to a predetermined point in SS an arc furnace 'These and other objects of this invention will be apparent from the following description thereof and from the annexed drawings, in which: Figure 1 is a sectionalised illustration of 60 the bottom portion of a consumable electrode arc furnace showing apparatus embodying features of this invention. Figure 2 is a section of the furnace of Figure 1 taken along the line 2-2 65 Figure 3 illustrates the electrode with the bore hole in the top. Figure 4 illustrates the apparatus of Figure 1 after the melting operation has consumed the electrode to the predetermined 70 extent. Figure 5 illustrates a modification of the apparatus shown in Figure 1. Referring particularly to Figures 1, 2 and 3, the apparatus of this invention is employed 75 in a consumable electrode arc melting furnace of any suitable design, which may comprise a crucible 10 enclosed around its sides and bottom by a housing 12, the space between the housing and the crucible forming 80 cooling water jacket 14 Disposed above the crucible housing 12 is a top housing with walls 16, which contains mechanism for lowering the electrode 18 into the crucible 10 at the desired rate Such mechanisms are well 85 known in the art and therefore are not shown in the drawings for simplicity and ease of understanding of this invention They will ordinarily include an electrode carrier 20 actuated from above, to which is attached at 90 its bottom by suitable clamps 22, or other equivalent means, electrode 18 As the meltGric Q 33 p 2 785,638 ing proceeds under the influence of the heat of the arc, metal is transferred from the electrode, which

is thereby consumed, into the crucible to form ingot 24, as more particularly shown in Figure 4 Melting is continued until only a short stub 18 a of the original electrode 18 remains Continued melting after this point is disadvantageous due to damage, by the proximity to the heat of the arc, to clamps 22, carrier 20 and other associated structures in this proximity. To indicate, externally of the furnace, when a predetermined desirable length of stub 18 a has been reached, the original electrode 18 is provided with a longitudinal bore hole 25, which is open at the top and extends into the electrode, terminating interiorly thereof at the point at which it is desired to obtain an indication of the stub length Above the electrode and in the line of sight of the bore hole is attached photocell 26 Current generated by the action of light on the photo-cell is carried through an exterior wall 16 of the furnace as by wires 28 and 30 to signal means 32, which will be actuated by such current The signal means may comprise a bell or signal light or both, or other indicia If desired or necessary, the current from the photo cell may be employed to actuate relays or may be strengthened by suitable electrical amplification or other control in order to actuate the signal means and alternatively or additionally, if desired, may be arranged to cause shutting off of the furnace power and operation. In the modification illustrated in Figure 5, the line of sight of the bore hole 25 is deflected by optical means to enable the comparatively delicate photo cell to be placed outside the furnace housing This is accomplished by provision of sight tube 34 which passes through the housing wall 16 and which is provided at its inner end with a reflecting surface, such as a mirror 36, aligned with the bore hole and at such an angle to reflect light received therefrom axially through the tube 34 Photo-cell 26 is then placed at the outer end of tube 34 and connections made to the relays and/or amplifiers, if employed, and the signal device. In operation, the electrode is first drilled downwardly from the top with a convenient diameter bore hole 25, which is of a length corresponding to the length of stub remaining at the point the signal indication is desired It will be appreciated that the bore hole may not necessarily be centrally located with respect to the ingot top surface but may i 60 be placed for convenience to avoid interference with the photo-cell or line of sight by other mechanism or construction in the furnace Then the electrode is placed in position and clamped to its carrier, the furnace evacuated or placed under inert atmosphere as the case may be, and melting accomplished in conventional manner When the melting has progressed to the point that the electrode has been consumed to the previously closed bottom end of the bore hole, 70 this hole will now be open and the intense light of

the arc will shine through the now open bore hole and affect the photo-cell, which will produce current to actuate directly, or indirectly, through relays or 75 amplifiers, the signal means.

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* GB785639 (A)

Description: GB785639 (A) ? 1957-10-30

Improvements in or relating to electromagnetic motors for razors, shears,clippers and like apparatus


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PATENT SPECIFICATION 785639 Date of Application and filing Complete Specification Feb 9, 1956. No 4100/56.

Application made in France on June 30, 1955. Complete Specification Published Oct 30, 1957. Index at Acceptance:-Classes 35, A 1 82 (D: F: J); and 131, M( 2: 6 B: X). International Classification: -B 26 b H 02 k. COMPLETE SPECIFICATION Improvements in or relating to Electromagnetic Motors for Razors, Shears, Clippers and like Apparatus We, INCOFIM S A, a body corporate organized under the laws of Morocco, of 81, Avenue Moinier Casablanca, Morocco, 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 in general to electromagnetic motors and more particularly to electromagnetic motors for driving cutting members, combs and grids of razors, shears and clippers, or the like, by imparting a reciprocating motion thereto. Cutting members of these types must be driven at a speed high enough to ensure a satisfactory operation of the apparatus in which they are mounted Besides, it is highly desirable their driving motors have a considerable strength combined with a smooth, noiseless operation To this end the number of moving parts of these apparatus should be as small as possible. It is the essential feature of this invention to provide an electromagnetic motor whereby the inconveniences briefly stated hereinabove are removed completely, this motor being remarkable notably in that it comprises on the one hand an electromagnet fed with alternating current and so shaped that the magnetic flux generated by it is divided or splayed into two symmetrical fluxes, and on the other hand a pair of movable members each adapted to receive one of said symmetrical fluxes and to be vibrated thereby so as to impart parallel reciprocating movements to at least two cutting members of the apparatus. According to another feature of this invention each of the aforesaid movable members consists of a resilient blade or the like, provided with an inertia block registering with corresponding pole pieces of the aforesaid electromagnet and adapted alternately to open and close the relevant magnetic circuit of said electromagnet. lPrice 3 s 6 d l At l A' From the foregoing it will be readily apparent that a motor constructed in accordance with the teachings of this invention is sufficient to actuate a double vibrating system adapted to drive one or more pairs of cutting 50 members. Besides, the free ends of each movable member vibrate synchronously and in opposite dirtctions, thereby compensating or neutralizing the

component forces acting on the 55 principal mass of the apparatus while suppressing not only the main source of resonance but also any vibration of a certain amplitude likely to develop in the apparatus and to become unpleasant for the user 60 Other features and advantages of this invention will appear as the following description proceeds with reference to the accompanying drawing forming part of this specification and showing diagrammatically by way of example 65 one possible embodiment of this invention In the drawing: Figure 1 is an elevational view with parts broken away showing a razor equipped with an electromagnetic motor made in accordance 70 with the teachings of this invention. Figure 2 is a plane view from above showing the motor of the razor of Figure 1, Figure 3 is a plane view from beneath showing the motor of the razor of Figure 1, and 75 Figure 4 is a vertical diagrammatical section taken upon the line IV-IV of Figure 2 and showing the motor separately. In the example shown in Figure 1 of the drawing the razor comprises a case 1 enclos 80 ing a driving motor 2 and a cutting head 3 contained in a detachable cover 4. The driving motor 2 comprises an electromagnet 5 consisting of a coil 6 and pole pieces 7, 8 disposed on either side of a central core 85 9 extending through the aforesaid coil and consisting for example of low-hysteresis iron laminations. Preferably this coil 6 may be provided with a copper-wire winding divided into a plu 90 e 785,639 rality of sections to permit the use of different mains voltages according to the known technique. The pole pieces 7, 8 extend transversely to the central core 9 and are substantially parallel to the planes of the coil turns; pins, studs or like members 10, 11 of non-magnetic metal extend through the centre of these pole pieces 7, 8 respectively, so that the magnetic flux induced by the coil 6 in these pole pieces will bifurcate at the level of these non-magnetic members 10, 11 in the direction of the arrows f (Fig 4), thereby forming two symmetrical splayed fluxes. Registering with the pole pieces 7, 8 are two parallel movable members 12, 12 ' disposed on either side of the electromagnet 5 and forming the two branches of a U-shaped blade Each movable member actually consists of a resilient blade 13 having secured thereon an inertia block 24 (or 24 ') made for example of laminations assembled by rivets, clips or the like, as shown diagrammatically at Both blades 13, 13 ', as shown in Figs. 1 and 2, may consist if desired of the two branches of a single U-shaped spring having its bottom secured by means of a screw-andwasher assembly 17 or the like to a depending lug 16 formed on the electromagnet core.

Of course, this arrangement should not be construed as limiting the invention as many details and proportions thereof may be altered without departing from the scope of the invention; thus, the resilient blades 13, 131 may consist of independent leaf springs each secured separately either on the core of the electromagnet or on any desired to suitable fixed portion of the case By providing the pair of washers or like plates 17 enclosing one portion of the spring the latter is reinforced locally at its fixation, thereby stiffening the spring and avoiding any permanent deformation likely to take place in service. The upper end of the resilient blades 13, 131 of each movable member is bent inwards at 14, 141 to form a frame-like member surrounding the electromagnet completely the free ends of these branches 14, 141 being bent in turn or formed with projecting lugs 25, 251 merging in the vertical axis of the apparatus. These projecting lugs 25, 251 are connected through resilient members such as coil springs 26, 261 or the like to cutting members 27, 271 of the cutting head of the apparatus These springs 26, 261 are provided for pressing the movable combs or grids against the fixed cutting grids or surfaces coacting therewith. The upper non-magnetic member 10 carries a rubber washer or pad 18 acting as a stop to a pair of depending tongues or lugs 19, 191 formed integrally on the upper bent portions 14, 141 of each movable member. These tongues 19, 191 by engaging the rubber washer or pad 18 reduce the amplitude of vibration of each movable member, thereby preventing the latter from striking the ends of the pole pieces 7, 8. Besides, a support 20 may be secured through a non-magnetic pin or like member 11 for example on the pole piece 8 for sup 70 porting electric terminals or like contacts 21, 21 ', 21 " 211 connected on the one hand to the different sections of the electromagnet winding and, on the other hand, to one end of an input conductor 22 adapted to be con 75 nected through its other end to a source of electric current. These contacts or terminals 21, 21 ' may be connected in the desired order by means of a sliding contact 23 of a switch 80 The device described hereinabove operates as follows:The electromagnet winding 6 is supplied with alternating current and the inertia blocks 24, 241 normally kept in their inoperative con 85 ditions at a suitable distance from the relevant pole pieces are alternately attracted and repelled at the frequency of the electric current supply Thus, these inertia blocks are vibrated to accomplish two parallel reciproca 90 tions taking place simultaneously but in opposite directions, upon each period this vibration being amplified and transmitted to the cutting combs or grids 27, 271 connected to the free ends 25, 25 ' of each resilient blade 95 13, 131.

Of course, each movable member may drive one or more cutting combs or grids, so that the motor is suitable for driving two or more pairs of cutting members parallel to the top 100 portion of the apparatus. It is advantageous to use non-magnetic pins 10, 11 for securing the motor assembly within the case 1, for example by threading the inner hole of these pins and screwing therein fixa 115 tion screws or the like, the heads of these screws being received and held against rota. tion in adequate recesses provided for this purpose in the inner walls of the case 1. Furthermore, the shapes of the movable 110 members, as well as of the pole pieces 7, 8 for alternately attracting and repelling these members, may differ from those illustrated, for example in view of reducing the over-all dimensions of the motor and consequently of 115 the apparatus. Of course, the invention is not limited to the form of embodiment shown and described herein, as many modifications may be brought thereto without departing from the spirit 120 and scope of the invention as set forth in the appended claims.


* GB785640 (A)

Description: GB785640 (A) ? 1957-10-30

Improvements in or relating to motor vehicle body construction



DE1081782 (B) DE1081782 (B) less

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PATENT SPECIFICATION 78 M 640 Date of application and filing Complete Specification: April 9, 1956. )No 10717156. Application made in Germany on April 9, 1955. Complete Specification Published: Oct 30, 1957. Index at acceptance:-Class 108 ( 1), B 3. International Classification:-B 62 d. COMPLETE SPECIFICATION Improvements in or relating to Motor Vehicle Body Construction We, Fo RD Mo TOR Co Mi PANY LIMITED, of 88, Regent Street, London, W 1, a Company incorporated under the laws of Great Britain, 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 a design of a motor vehicle body, equipped with what is known as a panorama wind-screen, that is to say, a wind-screen with the ends turned round towards the rear of the vehicle. In the known types of motor vehicle bodies with wind-screens of this kind, the pane is taken round to the front door-post, so that the door-post or its upper extension is within the driver's field of vision, and thus obstructs the driver's view to the left and to the right at the front. It is an object of the invention to obviate this disadvantage and accordingly the invention consists of a motor vehicle body having a front door and a wind-screen in which the wind-screen is extended so that one end thereof makes contact with a portion of the said door. Since, due to the omission of a door-post along the side edge of the glass there is no fixed connection at the front between the roof and the lower part of the vehicle body, a narrow retaining device is preferably accommodated in the neighbourhood of the side edge of the screen, according to the invention, which connects the roof firmly to the dashboard cowl, that is to say, to the lower part of the vehicle

body, and therefore ensures that the body has the required stability properties, and in particular will maintain its dimensions for the mounting of the windscreen. According to one embodiment of the invention, the retaining device can be a tension rope, which is anchored suitably at the roof and at the lower part of the body, or, according to another embodiment of the invenlPrice 3 s 6 d l tion, it is designed as a strut connecting the roof to the lower part of the body, and is conveniently equipped with a protective lip gripping round the free side edge of the 50 wind-screen along its entire length. The drawing shows examples of embodiments of the invention, and Figure 1 is a side view of the front part of a motor vehicle, 55 Figure 2 is a section along the line II-II of Figure 1, and Figure 3 is a modified design according to Figure 2. The motor vehicle 1 is equipped with what 60 is known as a panorama wind-screen 2, which is extended so that its side edges 3 reach the front door 4 The upper part of the front door, which makes contact with the wind-screen, is provided with a sealing 65 strip 5, preferably made of rubber, which prevents the ingress of draught into the interior of the vehicle, since it makes direct contact with the free end of the wind-screen 2, when the door is closed 70 In order to connect the vehicle roof 6 firmly to the lower part of the body 7, a retaining member 8 is accommodated near the free edge 3 of the wind-screen This retaining member can take the form of a tension 75 rope 9, which is fixed by means of suitable devices, for instance, clamps, to the roof and to the lower part of the body. Instead of the tension rope 9, a strut 10 extending from the roof 6 to the lower part 80 of the body may be used, which ensures a firm connection between the roof and the lower part of the body. It is convenient to provide this strut along its entire length with a lip 11, which sur 85 rounds the free edge of the wind-screen protectively. In order to eliminate vibration noises a suitable damping device, for instance, a strip of rubber 12, may be placed between the 90 strut and the screen. Since both the tension rope 9 and the strut can be kept very narrow, they hardly reduce the driver's angle of vision to the right and to the left at the front, so that the driver's field of view is not obstructed to any appre- S ciable extent. Various modifications may be made within the scope of the invention as defined in the appended claims.

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* GB785641 (A)

Description: GB785641 (A) ? 1957-10-30

Process for the preparation of fluorocarbons



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PATENT SPECIFICATION 785,641 i Date of Application and filing Complete Specification March 16, 1944. No.4963/44. Application made in United States of America on March 9, 1943. Complete Specification Published Oct 30, 1957. (Under Section 6 ( 1) (a) of the Patents &c (Emergency) Act, 1939 the proviso to Section 91 ( 4) of the Patents and Designs Acts, 1907 to 1946 became operative on April 4, 1957) r Index at Acceptance:-Class 2 ( 3), C 1 C(IA: IB: 7 A: 8: 1 F).

International Classification: -C 07 c 2. COMPLETE SPECIFICATION Process for the preparation of Fluorocarbons We, UNITED KINGDOM ATOMIC ENERGY AUTHORITY, of London, a British Authority, do hereby declare the nature of this invention and in what manner the same is to be performed, to be particularly described and ascertained in and by the following statement: - This invention relates to the catalytic fluorination, with elementary fluorine, of organic compounds which are hydrocarbons or partially fluorinated hydrocarbons containing more than two carbon atoms per molecule, and provides a method of catalytic fluorination by which relatively high yields of fluorinated product can be obtained. According to the invention there is provided a method for the catalytic fluorination, with elementary fluorine, of an organic compound having more than two carbon atoms in its molecule, this organic compound being a hydrocarbon or a partially fluorinated hydrocarbon, wherein fluorine and the organic compound in the vapour phase are mixed in the presence of the catalyst at a temperature of 1000 to 400 C. It is usually convenient to conduct the reaction in the presence of an inert gaseous diluent and to employ a slight excess of fluorine over that theoretically required for the conversion of the desired proportion of combined hydregen in the organic compound to -F groups. Examples of suitable diluents are: nitrogen, argon, helium and hydrogen fluoride. The catalyst preferably employed is one of those described in United States Patent SpeciBenzenen-Heptane Trifluoromethylbenzene a-, m-, or p di (trifluoromethyl)benzene 1: 3: 5 tri (trifluoromethyl) benzene IsobutaneToluenefication No 2,510,864, that is to say, one com 35 prising a heat-conductive metal base having thereon an adherent layer of a fluorine of silver, cobalt, manganese or cerium. The accompanying drawings illustrate apparatus by which the method of the inven 40 tion can be carried out. The apparatus shown in Fig 1 of the drawings comprises a reaction vessel having an internal copper wall 2 with a silver plating 3. The mixture of organic compound vapour 45 and nitrogen obtained by passing nitrogen gas from pipe 4 through the liquid organic compound in vessel 5 can enter the reaction vessel 1 by pipe 6 Nitrogen from pipe 7 mixes with fluorine in pipe 8 and the mixture is admitted 50 to the reaction vessel 1 The vessel 1 contains silverplated copper turnings 9 which are attacked by fluorine 'to form a catalytically active silver fluoride layer on the copper. When this has been formed, the mixture of 55 organic compound vapour and nitrogen is also admitted to the reaction vessel, and fluorinated

product and hydrogen fluoride pass from the bottom of the vessel by pipe 10 and the products are later separated The reaction vessel 60 is electrically or otherwise heated, by means not shown, so that the temperature of the catalyst therein is maintained at the desired value within the range 100-400 C The direction of gas flow is shown by the arrows 65 Yields exceeding 50 %/G of the theoretical value have been obtained in the fluorinations of the following compounds:CQH 1 + 9 F, =CF-2 + 6 HF CQH 1, + 16 F, =C 7 F,, + 16 HF C 6 H,CF, + 8 F, =CQ 7 F,, + SHF C 6 H 4 (CF), + 7 F,=,C F,6 + 4 HF C 6 H (CF), + 6 F,=CF,,+ 3 HF C 4 H, + 10 F 2 =C 4 F,, + 10 HF C 7 H, + 11 F,=CQF,4 + 8 HF Biphenyl, cetane, chrysene, retene, anthra impure heptane, gas oil and lubricating oil 80 cene, diamyl naphthalene and mixtures such as have been successfully fluorinated to corn ac lPrice 3 s 6 d l '& X 2 + 785,641 pletely fluorinated (" perfluorinated ") products. Waxes are principally produced by the fluorination of biphenyl, centane, anthracene, and n-dodecane, and oils are principally produced by the fluorination of chrysene, retene, diamyl naphthalene, polyisobutylene and most petroleum oils The oils obtained may be separated into a variety of products of different viscosities and boiling points They are thermally and chemically stable and some of them are good lubricants. The fluorocarbons formed in the reaction can be purified by washing with a solution of sodium hydroxide, separating and drying the washed product, and then fractionally distilling it. An illustrative preparation of CQ F 12, perfluorocyclohexane, follows: During a 14-hour period 36 9 grams of benzene vapor, 200 grams of fluorine and 333 grams of nitrogen were passed at uniform rates through the reaction vessel held at a temperature of 2650 C to 2750 C The products were then passed over solid potassium fluoride to remove hydrogen fluoride and the remaining fluorocarbons were then condensed The condensed mixture was allowed to separate into a gaseous and liquid fraction at about 27 " C. The latter material weighed 115 3 grams and of this 78 % was found to be C 6 F 1, When the temperature was reduced to below the optimum of between 2650 C to 2750 C, say at between 1500 C to 175 " C, fairly good yields of fluorocarbon boiling above 750 C up to 2000 C or more were obtained This was due to the presence of polymers produced by the reaction. In one fluorination procedure with n-heptane, fluorine flowing at a rate of 9 liters per hour, was mixed with nitrogen passing at a rate of 16 liters per hour, and the mixture was fed into the reaction vessel Nitrogen passing at a rate of 11 liters per hour was mixed with normal heptane vapor passing at a rate of 2 5 grams per hour and the mixture was fed into the reaction vessel containing a silver fluoride

on copper catalyst With the temperature of the reaction vessel maintained at about 130 " C -approximately 5 % by weight of the product was CF 1,, the remaining 95 % consisted of fluorinated heptanes containing one to three hydrogen atoms per molecule. Other fluorinations using an excess of fluorine yielded the following: When the temperature was kept at about 200 " C the yield of liquid fluorocarbon (mostly C 7 F,6) wasabout 45 % of the theoretical value At about " C the yield was 55 % and at about 10 T C to 110 " C yields as high as 80 % were obtained Under the particular conditions of flow a temperature range between 120 " C and " C gave the best consistent results. The area of catalyst surface exposed to the reactants can affect optimum temperatures of operation Under one set of conditions a 200 C temperature was found best, but when the surface area of the catalyst was increased nine times and the time of contact increased by one half, the optimum temperature for fluorination 70 of normal heptane fell to about 1000 C to C If the catalyst near the gas outlet is maintained at a slightly higher temperature than that at the inlets, the reaction is aided somewhat in going to completion 75 The following is an example of the preparation of fluorocarbon oils:A stream of fluorine flowing at a rate of about 50 liters per hour was passed in at one end of a reaction vessel The vaporized lubri 80 cating oil diluted by nitrogen, was carried into the reaction system at a rate almost sufficient to consume all of the fluoride The halogen was allowed to mix with the stream of vaporised oil in the presence of a catalyst compris 85 ing silver fluoride on copper turnings The vessel, filled with the catalyst, was heated to a temperature close to 3000 C The gases flowing from the outlet were passed through a tube cooled to about 200 C, where the less volatile 90 portion of the product condensed and was drawn off Additional fluorocarbon, together with hydrogen fluoride was collected in a second condenser which was cooled by subliming carbon dioxide The fluorocarbon phase 95 was mechanically separated from the hydrogen fluoride and the two portions of fluorocarbon were combined The liquid fluorocarbon was then refined by: ( 1) washing with dilute (about 10 %) caustic soda solution, ( 2) wash 100 ing with water, ( 3) drying with anhydrous potassium fluoride, ( 4) filtering, ( 5) distilling from an ordinary distilling flask under vacuum at 10 millimetres of mercury The distillation yielded a variety of colorless products of 105 increasing boiling point and viscosity Cuts taken below 100 C were very fluid at room temperature Those taken between 1000 C. and 200 " C were oily in texture and were of increasing viscosity Those boiling between 110 and about 250 " C were very viscous and tacky materials at room temperature The product boiling above 250 C

was brittle, with a texture similar to that of resin All of the higher boiling 115 materials became oils when heated sufficiently. Although the total yield of liquid fluorocarbon was about 60 % of that theoretically expected from the oil used, the yield of any one narrow boiling cut was of course much smaller 120 Condensed ring aromatic hydrocarbons such as naphthalene, anthracene or chrysene may be fluorinated to give products which in each case contain a high proportion of a saturated fluorocarbon of a narrow boiling range 125 The large cut obtained upon the distillation of a fluorinated anthracene boils at about 215 C at normal atmospheric pressure, while the main cut of the product from the fluorination of chrysene boils at about 140 " C at 10 130 785,641 mm of mercury pressure The former material is a wax and the latter is an oil at room temperature Such fluorocarbons have been readily produced using illustrative preparation method and condensing system described herein above. All of the fluorinations previously described in this application have been carried out in the presence of nitrogen as a diluent We have also obtained satisfactory yields of the desired liquid fluorocarbons by mixing undiluted streams of fluorine and vaporized hydrocarbons in the presence of a catalyst For example, isobutane and normal heptane were readily fluorinated in the system used for the fluorination of the oil, when the reaction vessel was held at temperatures between 1400 C and C. The method of the invention can be operated with the use of the apparatus shown in Fig. 2, in which the introduction of nitrogen gas into the liquid organic compound to be fluorinated in the vapour phase is controlled by a valve 11 affixed to pipe 4, and the replenishment of the liquid in vessel 5 is made through pipe 12 controlled by valve 13 Valves 14 and control the flow of nitrogen and fluorine gases through pipes 7 and 8 into the reaction vessel 1 The outlet pipe 10 leads to a vessel containing an absorbent 16 for HF, such as potassium fluoride, which may be continuously introduced by feeding through end 17 and withdrawn through end 18, both ends having removable stoppers 19 The fluorocarbons and unconsumed fluorine pass through tube 20, which leads into a cooling or condensing chamber 21 in which the greater part of the fluorinated products condense and from which they may be drawn off via tube 22 The greater part of the vapours from the first cooling chamber (largely fluorine) circulate through the vessel 1, passing through pipe 23, pump 24, flow regulator 25, flow meter 26, and pipe 27. There is, however, a second condensing chamber 29 (connected to the first by a pipe 28), into which pass part of the vapours leaving the first chamber 21 and in which more fluorinated product is condensed

This can be drawn off through pipe 30. Having now particularly described and ascertained the nature of the said invention, and in what manner the same is to be per-


* GB785642 (A)

Description: GB785642 (A) ? 1957-10-30

Improvements in or relating to cavity resonators


PATENT SPECIFICATION Inventor: LEONARD TONY KING Date of filing Complete Specification: July 21, 1954. Application Date: Aug 1, 1953. No 21401153. Complete Specification Published: Oct 30, 1957. Index at ecceptance:-Classes 39 ( 1), D(I 6 A 92 18 A; 46 A); and 40 (s), UW 8 (A 2: B 3). International Classification:-Hlj H 03 h. COMPLETE SPECIFICATION Improvements in or relating to Cavity Resonators We, ELECTRIC & MUSICAL INDUSTRIES LIMITED, a British Company, of Blyth Road, Hayes, Middlesex, do hereby declare the invention, for which we pray that a piatent 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 cavity resonators and particularly to such resonators which form tuned circuits in association with ultra high frequency electron discharge devices.

Discharge devices employing such resonators have been proposed for a variety of purposes, such as for the detecting or amplifying of high frequency oscillations, mixing high frequency oscillations and for generating high frequency oscillations. The dimensions of the cavity determines the resonant frequency of the resonator and in order to provide for adjustments in frequency to be made, it has previously been proposed to change the volume of the cavity by movement of one or more of the cavity walls It is an object of the present invention to provide an improved or simplified arrangement for tuning cavity resonators. According to one feature of the invention there is provided a cavity resonator comprising a pair of spaced walls and itherebetween an arcuate wall defining a substantially circular cavity said arcuate wall being arranged with its concave surface facing the axis of the cavity and including a section pivotally mounted at one end in such ia manner that it is free to move about lsaid pivot between said spaced walls, and means engaging said section to effect movement thereof so as to effect a change in the volume of said cavity. According to a second feature of ithe invention there is provided a cavity resonator comprising a pair of spaced walls and therebetween an arcuate wall defining a substantially circular cavity said arcuate wall being arranged with its concave surface facing the axis of the cavity and including a pair of Prtics 3 s 6 d l oppositely disposed sections each pivotally mounted at one end so that each of them is free to move about its pivot between said spaced walls and means engaging each of said sections to effect movement thereof so as to effect a change in the volume of said cavity. In order to prevent loss of power and reduce any tendency for the production of unwanted cavity modes to be set up, the surfaces of said movable section or sections which are adjacent the surface of said fixed walls are provided with A/4 chokes set A/4 away from the innermost surfaces of said movable section or sections. In order lthat the invention may be more fully understood, a tunable resonant cavity suitable for use with a known form of plug-in discharge device which forms with the cavity a ldystron oscillator will now be described. With the particular embodiment chosen to illustrate the invention the cavity is formed with an arcuate wall having a pair of oppositely disposed sections which are moved simultaneously to effect the tuning and this embodiment is illustrated in the accompanying drawings in which: Figure 1 is a cross section of a resonant cavity according to the invention and having a plug-in discharge device mounted therein and Figure 2 is a plan view of the resonant cavity of Figure 1. Referring to Figure 1 fixed walls 1 and 2 of a cavity resonator are

formed by a pair of circular plates mounted in spaced parallel relationship by securing them to diametrically oppositely disposed metal members 3 and 4. The wall 1 is provided with a circular aperture having its centre coinciding with the axis of the cavity and within this aperture there are arranged a series of contact making elements held in position by means of an iannulus 5 secured to the wall 1 An aperture of slightly smaller diameter is also provided in the wall 2 this aperture being in axial alignment with the aperture in the plate 1, its wall 6 being 785,642 s of frusto conical shape A clamping annulus 7 having a conical surface substantially complementary to ithat of the wall 6 is provided with means for firmly securing it to the wall 2 A plug-in discharge device to form with the cavity a klystron oscillator is shown in dotted outline at 8 The discharge device 8 is of the disc-seal Itype the external projecting portions of the electrodes being shaped so as to provide annular flanges for connecting them in associated equipment, the external flange of the electrode adjacent the reflector electrode being of cup shape and ithe external flange of the other electrode being of frusto conical shape To mount the device 8 in the cavity the clamp 7 is removed and the device inserted with the reflector electrode contact of the device passed foremost through the aperture in wall 2 until the conical flange provided on said device engages with the wall 6, at which position the cup shaped flange of the other electrode of the device will make electrical connection with the contacts in the aperture of wall 1 The device is then secured in position by means of the clamping annulus 7. The constructional form of the cavity will be more clearly seen from Figure 2 in which for the sake of clarity the wall 1 and also the device 8 have been omitted Referring now to Figure 2 the member 3 comprises a suitably shaped block forming a distance piece spacing the walls 1 and 2 and having at one end a flange coupling for connecting it to a wave guide or other utilisation circuit The surface 9 of the member 3 facing the axis of the cavity is of arcuate shape etending over an angle of and forming parts of the arcuate wall of the cavity The member 3 is provided with an aperture 10 through which high frequency energy passes from the cavity The member 4 comprises a substantially rectangular block secured to the peripheral edges of the walls 1 and 2 and having a portion on the side thereof facing the axis of the cavity of arcuate shape The member 4 assists in maintaining the walls 1 and 2 spaced apart and also serves to support an actuating member 12 for tuning the cavity as will be explained later To provide a cavity which is tunable over a relatively wide range of frequencies two sections 13 are provided each pivotally mounted at 14 so that they can be angularly moved between the walls 1 and 2 so that when ithe

sections 13 are angularly moved they increase or decrease the volume of the cavity and hence change the resonant frequency thereof The sections 13 are of rectangular cross section and have the arcuate form shown in Figure 2 each of said sections 13 extending over an angle of nearly 140 The ends of the -sections 13 adjacent the member 3 are inclined and can abut against surfaces on the member 3 having a corresponding angle of inclination and extending away from the arcuate surface 9. With the sections 13 in a position as shown in Figure 2 an arcuate wall defining a substantially circular cavity will be formed by the arcuate wall surface 9 and the arcuate surfaces of the sections 13 and this will correspond to the mid region of the frequency band over 70 which the cavity is tunable, the cavity becoming asymmetric on either side of the mid band position Each section wall 13 is capable of movement by plus or minus 90 from this mid band position hence giving a total angular 75 movement of 18 for each of the sections 13. The sections 13 are preferably pivoted at the ends thereof which are adjacent the member 3 as shown, but alternatively they may be pivoted at their other adjacent ends and in this 80 latter event they may be hinged together, said hinge being secured to the metal walls 1 and 2 Whichever expedient is adopted, it is preferable to arrange that the sections 13 are pivoted at their adjacent ends, whereby the 85 sections 13 may be moved in unison by a single actuating member thereby maintaining as near as possible the symmetry of the cavity. At the low frequency end of 'the tuning range of a cavity having the movable sections 90 13 pivoted at their ends adjacent the member 3 as above described, it may be found that the separation of the other ends of the sections may provide a gap size corresponding to the cutoff frequency of the device whereby leakage of 95 power from the cavity is liable to occur In order to substantially prevent such leakage an electrically conducting post 15 of small dimension may be arranged benveen the plates 1 and 2 in a position whereby the gap formed when 100 the sections 13 are moved apart is in effect divided in half. The thickness of the movable sections 13 will be such that they will make a reasonable sliding fit between the walls 1 and 2 but in 105 order to prevent leakage of power and to produce what is equivalent to a short-circuit between the sections 13 and the walls 1 and 2 at the operating frequency, it is preferable to arrange A/4 chokes 16 on the surface of both 110 of said sections 13 which are adjacent the walls 1 and 2 said chokes 16 being spaced A/4 from the arcuate surface which forms the enclosing wall of the cavity and as shown may consist of arcuate channels A/4 in depth Furthermore 115 the provision of these chokes 16 will discourage the production of unwanted cavity modes. Although many ways for controlling the angular movement of the

sections 13 for effecting tuning of the cavity will readily be 120 apparent, the following has been found to be satisfactory for operating ia cavity constructed in the above described manner The movable section's 13 are connected to leaf springs 17 by means of screws 18 the other end of the 125 springs being anchored to the walls 1 and 2 via post 19 The springs 7 urge both of the sections 13 radially outwards to force the free ends thereof into engagement with an arcuate metal strip 20 The strip 20 is supported by 130 785,642 785,642 a tubular guide 21 arranged so as to be axially movable in a close fitting aperture in the member 4 The actuating member 12 comprises a plunger 22 controlled by a micrometer screw so as to impart only very small axial movement thereto and ia corresponding radial movement of the strip 20 As the strip 20 is moved inwards towards the axis of the cavity the sections 13 are urged radially inwards and the resonant frequency of the cavity thereby increased. Since this movement provides an approximately linear frequency/movement curve the reflector electrode supply voltage may be conveniently ganged to the micrometer movement to maintain the device in oscillation throughout its tuning range For this purpose a potentiometer may be ganged to the actuating member 12 by coupling it to the extension of the plunger 22 at the end 23 thereof. It has been found that a cavity resonator constructed in this manner with an electron discharge device plugged into the aperture in the walls can be operated in the 3 A/4 cavity mode at a frequency in the 10,000 Mc/s region and that a tuning range of over 15 per cent to the half power points can be achieved by movement of the cavity sections. Although the invention has been described with reference to a tunable cavity resonator which is directly associated with an electron discharge device, modified forms of cavity resonators according to the invention may be constructed for use as variable circuit elements for use for purposes other than in association with electron discharge devices.


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