* GB784913 (A)

Description: GB784913 (A) ? 1957-10-16

Improvements in or relating to electric primary cells

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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 Inventors: ALFRED RENE JOHN PAUL UBBELOHDE and SAMUEL ERIC ROGERS Date of filing Complete Specification July 24, 1956. Application Date May 9, 1955. Complete Specification Published Oct 16, 1957. Index at Acceptance: -Class 53, BP 1 (A: B: C: K: M), BP( 3 A: 3 C: 5). International Classification: -H Olm. COMPLETE SPECIFICATION Improvements in or relating to Electric Primary Cells We, NATIONAL RESEARCH DEVELOPMENT CORPORATION, a British Statutory Corporation, of 1, Tilney 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: This invention relates to the manufacture of primary cells of the kind comprising an anode, a cathode and an electrolyte, for use as a source of electric current. It is an object of the present invention to provide a new and simple type of primary cell which can be used as an alternative to existing dry cells. According to the present invention there is provided a primary cell having as its electrolyte an aqueous solution of a soluble thio2 C

cyanate Preferably an alkali metal thiocyanate is used A 50 % by weight concentration of potassium thiocyanate is preferably used. In such a cell the material forming the anode may be graphite, graphite carbon, copper or silver, while the material used as the cathode. may be magnesium, zinc or silver alloys having a high content of magnesium, zinc or silver. Magnesium is preferably used as the cathode since although zinc and silver are used with very steady functioning the E M F is lower then when magnesium is used. The cell may also include filler materials such as glass wool, felts of Terylene (Registered Trade Mark) or nylon, alumina, granular plastics, cellulose powder or wood flour. Such a cell may be made up as a dry cell in which case the top is covered with bitumentype wax or a plastic top in which it is desirable to leave an air vent. A preferred embodiment of a so-called dry cell is now described by way of example only. EXAMPLE The test cell has a cylindrical graphite rod approximately 3 mm in diameter which is surrounded by a thick paste made up with powdered graphite and a solution of potassium thiocyanate The paste is contained in a cotton bag surrounding the graphite rod and the outside diameter of the bag is approximately 15 mm Around the bag a thick paste of potassium thiocyanate solution in alumina separates the anode from the cathode which is made from a flat sheet of 22 gauge magnesium (chromated surface) bent into cylinder of about 35 mm. diameter and about 40 mm deep, immersed in the alumina paste The electrodes are approximately 10 mm apart all the way round and the whole assembly is contained in a glass vessel. The cell thus formed has an E M F of 1 5 volts on open circuit at room temperature. When discharged across a recording milliammeter of nominal impedance 2 ohms, apart from a high initial peak (corresponding to an internal resistance of about 0 5 ohm, and lasting about 1 minute), the shape of the output curve and the total cell capacity (approximately 4.5 ampere-hours) are closely similar to the corresponding behaviour of a known 1 5 volt dry cell, as used commercially After the initial peak, the internal resistance of the present cell remains fairly uniform at about 5 ohms. In the dry cell described one advantage is that no depolarising substance need be added.

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* GB784914 (A)

Description: GB784914 (A) ? 1957-10-16

Polarised electromagnetic relay

Description of GB784914 (A)

PATENT SPEC 1 WFICATION 784,914 Date of Application and filing Complete Specification Aug 10, 1955. No 23012/55. Complete Specification Published Oct 16, 1957. Index at acceptance: -Classes 3 S(S), I(D 1 A: J 1 M 4: N 2), B 32 A(I 1: 12 D); and 40 ( 1), H 11 B 6 C. International Classif Lcation: -GO 8 c H 02 c. COMPLETE SPECIFICATION Polarised Eliectromagnetic Relay We, STANDARD TELEPHONES AND CABLES LIMITED, a British Company, of Connaught House, 63, Aldwych, London, W C 2, England, do hereby declare the invention (communicated by C Lorenz Aktiengesellschaft, a German Company, of Stuttgart-Zuffenhausen, Hellmuth-Hirth-Strasse 42, Germany), 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 invention relates to a polarised electromagnetic relay, particularly for small type radio equipment such as that built into vehicles, and to circuits for operating said relay. In such small type radio equipment in order to save space only a switching device is placed at the operator's position for the remote control of the speaking and listening facilities, and the main equipment comprising the transmitter and the receiver and the current

supply apparatus, is accommodated in an adjacent chamber of the vehicle. The quartz crystals which are necessary for the selection of the difference speech channels must be arranged for technical reasons near the transmitter and it is frequently the case that they have to be kept at constant temperature with the aid of thermostat regulators. Consequent 11 the selection of the quartz crystals has to be remotely controlled and in cases where only a small number of channels are concerned this is normally effected by means of relays. With an increasing number of channels, however, this necessitates a considerable accumulation of relays, an increase in the number of feeder lines, and a continually flowing current to hold the energised relays which in the case of vehicles is a great disadvantage owing to the limited source of current. Rotary switches are a 4 so known for selecting the individual channels These, however, require special and very sensitive devices for the generation and conversion of impulses and in addition are insufficiently shock-proof, so lPrice 3 s 6 d l that they are unsuitable for use in vehicles. Furthermore switches are known using very small motors, but these require a larger number of mechanical movable components, such as a toothed wheel and worm gear, Counter shaft, brake, trailing contacts and also a greater number of feeder lines. In contrast thereto it is possible, by employing the relay according to the invention to select by remote control any one of, say, twelve quartz crystals or channels by means of a single relay, which is controlled over three feeder lines only and which is automatically de-energised after each switching operation Thus the only mechanically movable components required are one shaft or spindle which can be rotated and also moved longitudinally. According to the invention there is provided a rotary switching relay comprising an armature consisting of a permanent magnet mounted for rotational movement about an axis perpendicular to its magnetic axis and for longitudinal movement along its rotational axis, a magnetic yoke provided with a plurality of pole pieces, a plurality of separate windings one carried on each pole piece, and switching means for connecting the windings in selected manners to a source of current, whereby the armature can be rotated into any one of a number of preselected angular positions by appropriate energisation of one or more of the windings and whereby the armature is displaced longitudinally, the armature being returned to its original longitudinal position upon the cessation of said energisation. The controlling circuit is only energised during the actuation of the switch because the relay is automatically de-energised after each

switching operation, thus avoiding any unnecessary loading of the battery A further feature of the invention provides that the armature and the associated switching contacts are held by means of a ratchet when the poles are not energised so that the relay is secured against any accidental displacement caused by vibrations or shocks This holding is effected by the action of a spring which also withdraws the armature from the field of the poles When the windings are energised, the armature with the switching contact is pulled into the field in opposition to the action of the spring, thereby removing the holding effected by the ratchet, and lifting the actuating springs off the contacts The selective energisation of the windings is remotely controlled by means of a control switch. The invention will be particularly described with reference to the embodiment shown in the accompanying drawings, in which:Fig 1 is the view of an embodiment of the invention in selectional elevation; Figs 2 to 5 show some details concerning is Fig 1; Fig 6 is a schematic representation of a magnetisation sequence according to the embodiment of the invention; Fig 7 is the view of a control switch for use with the relay, in sectional elevation; Figs 8 and 9 show some details concerning Fig 7; Fig 10 shows one,detail of a modified relay according to the invention; Fig 11 shows, in a schematic representation, a circuit arrangement for the pole windings of Fig it); Fig 12 shows schematically another example of a magnetisation sequence according to the embodiment of Figs 10, 11. In Fig 1 the rotary armature 1 is a conical shaped permanent magnet mounted on the spindle 2 This spindle is pivoted in the bearings 3 and 4 and is also displaceable in its longitudinal direction. Around the armature there is arranged a laminated soft-iron yoke with three poles 6, 7 and 8 (Fig 3), staggered by 1200, pointing towards the armature of the magnet The faces of these poles, have the same conical angle as the armature 1 These poles, which determine the selective magnetisation are provided with windings of copper wire. The armature 1 is normally retained in the position shown by the action of the spring 9 (Fig 1). When the contact 11 (Fig 6) is closed and the source of current 12 thereby switched on one or more of the Doles 6, 7 and 8 will be magnetised by current flowing through the coils and the armature 1 will overcome the action of the spring 9 and be pulled upwards into a position between the three poles 6, 7 and 8 (Fig 3) as shown in dotted lines in Fig. 1 At the upper end of the spindle 2 of the armature 1 there is mounted on an insulating disc 13 a contact spring 14, the spring being furnished with a contact of a noble metal The current is supplied via the spring 17 which makes continuous contact with the slip ring 17 b

carried in the lower surface of the insulating disc 13 The slip ring 17 b is permanently connected to a metallic pin 17 a which passes through the insulating disc 13 and is connected to she contact spring 14 In a circle around a ring of insulating material 15 (Figs 1 and 2) there are arranged twelve fixed contact pieces 16, also provided with contacts of noble metal, and which are connected to the 12 quartz crystals 70 The pin 18 extending through the spindle 2 of the armature 1 and engaging the fixed circular ratchet 19 serves to hold the switch in the selected position when the relay is in the de-energised condition Instead of only one 75 switching plane or level as represented by insulating ring 15, there may be arranged a plurality of rings mounted above one another on the spindle 2. By actuating the control switch (Figs 7 to 80 9) there will become effective in successive order a total of twelve switching combinations, which effect a corresponding polarisation of the magnetic field and thereby cause the armature 1 to take up the selected position out of 85 twelve possible positions equally distributed around the circumference. The schematic representation of Fig 6 shows the successive order of the switching combinations for the magnetisation of the 90 windings when the control switch is rotated step-by-step in one direction of rotation, each time stepped through 30 . Fig 4, for example, shows the position of the armature in relation to the pole pieces cor 95 responding to position 4 of Fig 6 in which, as in positions 2, 6, 8, 10 and 12 are two potentials of the same sign and one potential of an opposite sign applied to the field windings, so that all three pales are energised By this 100 arrangement the pole piece 7 is ineffective, because at both ends of its winding there exists the same (negative) potential and the armature takes up a position across the two poles 6 and 8 105 Fig 5, on the other hand, shows the position of the armature with respect to the pole pieces in the switching position 3 (of Fig 6) which is similar to switching positions 1, 5, 7, 9, 11; in each of which one winding is ener 110 gised Thus in this example the north pole of the armature fully opposes the pole piece 8, whereas the south pole of ehe armature partially opposes both the poles 6 and 7 which have the same polarity 115 The control switch Gas s Lown in Figs 7 to 9) consists of six contact springs 20, three of which are arranged on each side of the operatng cam cylinder 21 which is pivoted betwveen two bearings, and bear firmly upon the said 120 cam cylinder 21 The switching cam cylinder 21 is of insulating material and is provided with recesses corresponding to the springs 20. When the cam 21 is rotated the springs 20 are released in a successive order and press 125 against the contact pieces 22, so that the

positions shown in Fig 6 are successively switched from positions 1 to 12. The control knob 23 is mounted on an ayle 24 which is supported in a longitudinally dis 130 784,914 oft direct switching of the rotary relay (e g. for testing purposes) is possible by manually depressing the knob 10 on the relay and turning it to the desired position The rotary relay will be securely held in the new position by 70 the circular ratchet. Instead of a delta connection for the coils of the rotary relay as shown in Fig 6 there may also be employed a star circuit similar to that shown for five windings in Fig 11 In this 75 case the same principle is followed as described above and it is also possible to switch a five-pole rotary relay comprising 20 fixed positions and this requires only five feeder lines 80 In Fig 10 a five pole arrangement is shown schematically. Fig 11 shows an arrangement of the windings which could be employed for this purpose The different combination possibilities 85 are shown in Fig 12 If the succession of combinations shown for the switching positions 1 to 20 is followed there will result an equal progressive turning of the armature in one direction of rotation of 180 for each step 90 If the quartz crystals were connected in multiple combinations it would be possible to select them by employing two three-polar systems and two control switches over only six feeder lines and with a total of twelve quartz 95 crystals 12 times 12, i e 144 different channels could be obtained. Similarly by employing two five-polar systems and ten feeder lines it would be possible to select 20 times 20 =i e 400 different 100 channels. The invention is not limited to the embodiment described but can be applied to all kinds of circuits requiring a number of switching positions which are to be remotely controlled 105 For example a plurality of rotary relays, which are arranged separately in different completely closed chambers or spaces, could be synchronously and remotely controlled with the aid of only one control switch 110

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* GB784915 (A)

Description: GB784915 (A) ? 1957-10-16

Improvements in or relating to shielding means for holders of electronicvalves and other electrical devices

Description of GB784915 (A)

PATENT SPECIFICATION Inventor: ANTHONY BRASIHER CLEWES 784,915 Dare of filing Complete Specification: March 5, 1956. Application Date: Sept 29, 1955. No 27782/55. l Complete Specification Published: Oct16, 1957. Index at acceptance:-Class 38 ( 1), E 3 (A 11 B: E 4 B), E 29. International Classification:-HO 2 f. COMPLETE SPEGIFICATION Improvements in or relating to Shielding Means for Holders of Electronic Valves and other Electrical Devices We, CARR FASTENER COMPANY LIMITED, a British Company, of Pinfold Lane, Stapleford, Nottinghamshire, 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 described in and,by the following statement:- This invention relates to means for electrically shielding the projecting contacts of an electrical device and more particularly, although not exclusively, to means for shield& ing the solder tags of a valve-holder. According to the present invention there is provided a combination of an electrical device, for eample, a valve-holder, comprising 1 a body of insulating material 'having 'a contact or contacts projecting from one face thereof, and an anti-corona shield secured to said body and projecting therefrom so as to surround the contact or contacts, the shield in co-operation with a portion of the body providing means whereby the combination can be secured in an aperture in a support. The present invention also provides an anticorona shield having a tubular shaped body portion formed at one end with a smoothly rolled rim and at the other end with a plurality of ears which project inwardly of the body portion, the ears providing means whereby the shield can be secured to the insulating body of an electricai device,

for example, a valve-holder. One embodiment of the present invention will now be described in greater detail, by way of example only, with reference to the accompanying 'drawings, of which, Fig 1 shows a view from underneath the embodiment mounted in an aperture in a chassis, panel or the like, Fig 2 shows a side view partly in crosssection of the embodiment; Fig 3 ' shows a plan view on an enlarged scale of the ani-1 corona shield of Fig 1; lPrice 3 s 6 d 1 Fig 4 shows a cross-section on line A-A Fig 3; and 45 Fig 5 shows a detail view of the shield of Fig 3. As shown in Figs 1 and 2 of the drawings, the electrical device 1 is a valve-holder which comprises a body portion 2 of circular cross 50 section, formed of insulating material,, from the lower face 31 of which projects a plurality of solder tag contacts 4 The body 2 is formed on its side wall 5 with a laterally projecting peripheral ridge 6, the function of which 55 will become more apparent later in the description. Secured to the body 2 and projecting therefrom so as to surround the contacts is an anti-corona shield 7, the free end 8 of which 60 projects beyond the free ends of the contacts 4 and is rolled radially inwardly upon itself to form a smoothly curved rim 9 The other end 10 of the shield 7 is bent radially inwardly to form a flange 11 which is divided' 65 by a plurality of, for example, eight, semicircular notches 12 into a series of ears 13, 14 which are bent to project alternately inwardly and outwardly respectively of the shield 7; the inwardly projecting ears 13 form 70 ing an angle of approximately 15 with the plane of the flange and the outwardly projecting ears 14 forming an angle of approximately 25 with said plane The innermost edge 15 of each of the ears 13 lies on a circle 75 which is slightly 'smaller in diameter than that on which the 'edge 16 of each of the ears 14 lies and also slightly smaller than that of the lower portion 17 of the body 2 of the valveholder It will be seen, therefore, that when 80 the shield 7 is pressed on to the lower portion 17, the inwardly projecting ears 13 will dig into the body 2 and thereby retain the shield 7 in position on the valve-holder 1. The shield 17 is preferably formed of brass 85 and is nickel plated. 4 ', ' As shown in Figs 1 and 2 the valve-holder 1 and the shield 7 are mounted on a support 18 which comprises a plate of insulating material provided with an aperture 19 in which the valve-holder and shield are mounted, the support being clamped between the ridge 6 on the valve-holder and the ears 14 of the shield which resiliently engages the lower face 20 of the support The support 18 is also provided with holes 21 by which the support is secured to a chassis, panel or the like 22 provided with an aperture 23 through which the shield 7 extends, by means of eyelets 24 Intermediate the aperture 19

and the holes 21 there are provided bolster-shaped air gaps which serve to increase the electrical resistance between the shield 7 and the chassis 22. In this embodiment there is also provided a second anti-corona shield 26 of similar construction to that of the shield 7, which projects from the body in a direction opposite to that in which the shield 7 projects and is secured to the body 2 on the opposite side of the ridge 6 to that on which the shield 7 is secured This shield 26 serves to prevent corona discharge from prongs of a valve inserted into the holder 1. In operation, the high potential contact is electrically connected to the shield in known manner. It will be appreciated that modification of the above described embodiment may be made without departing from the scope of the invention, for example, the shield may be provided with a screw-threaded portion which co-operates with a similarly threaded portion on the insulating body of the valve-holder ' Again, if the chassis is itself of insulating material, the valve-holder and shield may be mounted directly on the chassis in the 'manner above described for mounting them on the plate. Although the invention has been described as applied to a valve-holder, it will be appreciated that the invention is applicable,o other electrical components where high potentials are employed.

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* GB784916 (A)

Description: GB784916 (A) ? 1957-10-16

A magnetic powder clutch

Description of GB784916 (A)

PATENT SPECIFICATION X' B 'Date of Application and filing Complete Specification: Oct 7, 1955. No 28615/55. ( 2 3 y Application made in Germany on Oct 7, 1954. Complete Specification Published: Oct 16, 1957, Index at acceptance: -Class 35, A 1 (G: J). International Classification:-H 02 k. COMPLETE SPECIFICATION A Magnetic Powder Clutch We, ELEKITRO-MECHANIK G M B H, of Wendenerhfitte Uiber Olpe i/Westf, Germany, a German Body Corporate, 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 invention relates to magnetic powder clutches of the kind comprising two clutch members forming a gap to receive the magnetisable powder and a stationary coil for the energisation of the clutch Conventional magnetic powder clutches of this kind are designed in such a manner that the energising coil as well as the members for ts Support surround the two clutch members. According to the invention, a magnetic powder clutch comprising two clutch members which form a gap, an energising coil, and magnetisable powder to fill the said gap, is characterised in that the two clutch members are coaxially arranged so that one surrounds at least part of the other, that an annular space open at one side is formed within one of the clutch members or between both clutch members, and that a stationary energising coil projects into the said annular space through the open side thereof This construotion has the advantage, apart from the convenient stationary arrangement of the energising coil, that the one of the rotary clutch members may 'be designed as a belt pulley, gear, or Ithe like and thus serve directly for the drive. 35,In order that the invention may be clearly understood an embodiment thereof will now be described by way of example with reference to the accompanying drawing which shows a longitudinal section through;a clutch according to the invention. As shown, the one clutch member consists of a sleeve 12 which is provided 'alt one end with a flange 13 which extends radially outwards from the sleeve 12 and 's then bent backwards, i e in an axial direction so as to form a cylindrical portion which projects into the working gap of the clutch as will be delPrice 3 s 6 d l scribed hereinafter The sleeve 12 and its flange 13 may be made of two pieces, as shown, connected together by means of screws.

The sleeve 12 is mounted on a shaft 9 and rigidly connected to it by means of a screw 8 Alternatively, the sleeve 12 could be omitted and the flange 13 could be fastened directly to the shaft 9 This shaft may be the driving shaft of a motor, but also the drive shaft of a machine or a gear transmission for the drive of,a machine. The other clutch member 14/15 surrounds co-axially the above described clutch member and is supported by the latter by means of bearings 16, so that both members are free to rotate one independently of the other The space in which the bearings are located is sealed by means of a seal 18 The outer clutch member consists of two co-axially disposed parts 14 and 15 which are connected tog ther by a ring 20 There are l ft two axially adjacent annular spaces between the two parts 14 and 15 of the outer clutch member, a narrower annular space 22 and a wider annular space 25, and the said spaces are separated from one another by means of the said ring However, the outer clutch member could be made from one piece with the said two annular spaces formed therein The narrower annular space 22 forms the working gap of the clutch, and into this space extends the backwards bent porsition of the flange 13 which forms part of the first mentioned clutch member The spaces 17, which accommodate the magnetisable powder, are closed by a removable lid 19 During operation, the powder will be concentrated in a space indicated by dotted shading The part 14 of the outer clutch member is shaped to form a pulley for a Vbelt transmission Alternatively, it may form a plain belt pulley or a gear. The wider annular space 25 between the two parts 14 and 15 of the outer clutch member accommodates the energising coil 10 As shown, the coil 10 extends from the one side into the annular space 25 and it is supported by a cylindrical portion 26 of a flange 11 784,916 which is stationary and may be screwed to : the bearing shield of the driving motor, or to the gear box of the power transmission, or to the frame of the working machine, as the case may be Since the outer clutch member revolves during operation, whilst the flange 11 is stationary, there is left a narrow gap 23 between the part 15 of the clutch member and the cylinder 26 which supports the coil 10, and a kind of labyrinth seal 24 is provided between the part 14 of the outer clutch member and the aotual flange 11. When the energising coil is switched in, the magnetic flux, indicated by a dotted line 21, passes through ithe followving members: flange 11 including its cylindrical coil supporting part 26, gap 23, part 15 of the outer clutch member, magnetisable powder, cup-shaped portion of ithe inner clutch member, part 14 of the outer clutch member, and through the gaps 24 forming the seal between part 14 and the flange 11 The ring 20 will be made of a non-magnetic material to ensure that the flux passes through the werking gap, 22 Thus a

coupling is effected between the clutch member 13 which is connected to the shaft 9 and the outer clutch member 14/15 which forms the V-belt pulley. It will be appreciated that the invent ion is not limited to ithe construction shown in the drawing and that many modifications are possible without departing from the scope of the invention For instance, it would be possible to locate the two annu' ar spaces 22 and 25 between the two co-axial clutch members, i e. between the sleeve 12 of the inner clutch member and the part 15 of the outer clutch member, and to separate in an axial direction the two spaces 22,and 25 by means of a seal which allows a relative rotary movement of the two -clutch members.

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* GB784917 (A)

Description: GB784917 (A) ? 1957-10-16

A new or improved hollow stopper for bottles and the like

Description of GB784917 (A)

COMPLETE SPECIFICATION A new or improved Hollow Stopper for Bottles and the like I, [Dr. Ing.] HERBERT BRUNE, a German Citizen of Kolner Strasse 9, Porz bei Koln, Germany, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is is to be performed, to be particularly described in and by the following statement:- The invention relates to a hollow stopper for bottles, tubes, or the like of resilient plastic, such as, for preference, polyethylene.

Hollow stoppers have ibeen proposed, which consist essentially of a cover plate and a cylindrical part with at least one sealing ring. The hollow stopper of the present invention has the feature that it is provided with a cylindrical 'guide portion preferably situated Ibeneath the cover plate having a diameter slightly less than the sealing ring or rings.. The length of the cylindrical guide portion conveniently amounts to at least half of the clear distance between the cover plate and the uppermost sealing ring. In this way a secure fit of the hollow stopper in the mouth of the container is ensured. The hollow stopper is well guided in the mouth of the container and on the other hand can also be properly withdrawn. It is thus possible for the stopper to be re-used as a sealing means after some of the liquid has been withdrawn from the container. The cylindrical guide portion and the cylin- drical portion of the hollow stopper carrying the sealing rings are preferably of aplproxi- mately the same wall thickness. In this way, good elasticity of the cylindrical guide portion in the radial direction is ensured. Preferably the cylindrical portion of the stopper with the sealing ring or rings is of less din meter than the cylindrical guide portion, the transition between the diameter of the two portions being a gradual taper. Another feature of the invention consists in that the cylindrical guide portion can be provided with grooves, which run parallel or at an angle to the axis of the stopper and which ventilate the space above the sealing ring or rings. The cylindrical portion carrying the sealing rings preferably has, below the lowermost seal ing ring, a portion of larger diameter than above said ring. The lower ring is thus stiffened giving a better sealing effect. In order to permit good introduction of the stopper into the mouth of the container, the cylin drical portion carrying the sealing ring is conically tapered below the lowermost ring. The hollow stopper of the invention can be produced from resilient plastic in a single operation. It can, in known manner, be closed at the top or have a base at the Ibottiom. A special inserted plate can, be provided as top closure, and can be made of a rather stronger material, in order to reinforce the stopper. Impressions, printing, or the like can be pro vided own the inserted plate. Three embodiments of the invention are illustrated las examples in the

accompanying drawings, in which: Figure 1 shows a longitudinal section through a stopper, Figure 2 a longitudinal section through a form of construction with an inserted plate, Figure 3 an elevation of a third form of construction, Figure 4 a section through a stopper hav ing a top closure plate, Figure 5 an elevation of a stopper for champagne bottles. Figure 6 a section through a second form of construction of a stopper for champagne bottles. Figure 7 a view from above of Figure 6, with the closure head removed, and Figure 8 a partial view. The stopper consists of a cylindrical por- tion 1, forming a cylindrical guide portion and lying below the cover plate 2. The cylindrical guide portion 1 merges into a cylindrical portion 3, which carries one or more sealing rings 4. Below the lowermost sealing ring 4, the !cylindrical portion 5 is formed of larger diameter than above the lowermost sealing ring 4. The transition from the cylindrical guide 1 to the cylindrical part 3 is a gradual taper and the arrangement is preferably such that the length of a of the cylindrical guide portion 1 amounts to at least half of the clear dis tance b between the cover plate 2 and the uppermost sealing ring 4 (Figure 1). In this way, secure guiding of the stopper in the con tainer mouth is obtained. The stopper cannot tip or tilt. The cylindrical guide portion 1 may be pro vided with grooves 7, which run parallel to the axis of the stopper, or else at an, angle thereto, or helically, and so on. By means of these grooves 17 the space above the sealing rings 4 is vented during the insertion of the stopper. On the other hand, when the stopper is drawn out, this space is 'brought into com munication with the atmosphere, so that no vacuum is produced which would hinder the extraction of the stopper. The grooves 7 are

of particular interest in cases where, in the interests of perfect sterilisation, the bottles are filled to the uppermost rim of the mouth before sealing. The liquid displaced through the stopper can escape through the grooves 7 when the stopper is inserted. As shown in Figures 1 to 3 and 5 to 7, the stopper can be closed at the bottom by a bottom plate 9. As shown in Figure 4, how ever, the stopper can also be open at the bottom, while the cover plate 2 fully closes the top aperture. Finally, it is also possible to press or engage an inserted plate 8 into a stopper which is open at the top. In the embodiment illustrated in Figures 5 to 7, the cover plate 2 is also made hollow. On its top edge is mounted a hollow closure head 11, which is provided with ribs 12 to reinforce it and improve grip. The hollow closure head 11 can be welded to the cover plate 2, or one part may snap into the other. The tool for producing the stoppers is preferably so constructed that the bottom part 10 and the lowermost ring 4 are seamless. The seam 20, which is unavoidable with a jaw tool is restricted to the space above the bottom ring 4. Only in this way can absolutely secure sealing be obtained together with the necessary thickness of the bottom ring 4. The hollow closure head 11 can have a depression 13 at the top. A suitably curved retaining stirrup, such as is known for closing champagne bottles, engages therein by a bent over part. The advantage is thereby obtained that the additional support plate, which in the Imown manner is welded to a retaining stirrup, can be- dispensed with. The applica tion of the stirrup and its positioning in the correct position are ensured by the depression 13. The hollow closure plate 2 and the hollow closure head 11 can each carry a cylindrical attachment 18 and 19 respectively, which en -gage in one another when the two parts are placed one on the other, and hence secure

the position of the closure head 11. The welding between the closure head 11 and the cover plate 2 may be effected on the outer periphery of the two parts. To this end, in order to secure the central positions on the closure head 11, a groove 14 can be provided on the closure head 11, and an annular raised portion 15 on the hollow cover plate 2 (Figure 6). The hollow closure head 11 and the cover plate 2 can also be welded together in the region of the cylindrical attachments 18 and 19. In order to ensure against the turning of the two parts in relation to one another, teeth 16 can in this case be provided on the outer periphery. The hollow stopper of the invention is suitable in particular, as tests have shown, for 'closing wine bottles and bottles containing sparkling beverages, such as champagne bottles and the like. What I claim is: 1. A hollow stopper for bottles, tubes, or the bike, ef resilient plastic, such as, for preference, polyethylene, having a cover plate and a cylindrical portion with at least one sealing ring, characterised in that bow the cover plate a cylindrical guide portion is provided having a diameter slightly less than the diameter of withe sealing ring or rings. 2. A hollow stopper according to claim 1, characterised in that the length of the cylindrical guide portion amounts to at least half the clear distance between the cover plate and the upper sealing ring. 3. A hollow stopper according to either of the preceding claims, characterised in that the cylindrical guide portion and the cylindrical portion carrying the sealing ring or rings have approximately the same wall thickness. 4. A hollow stopper according to any of the preceding claims, characterised in that the cylindrical portion of the stopper with the sealing ring or rings is of less diameter than the cylindrical guide portion, the transition between the diameter of the two portions being a gradual taper. 5. A hollow stopper according to any of the preceding claims, characterised in, that the cylindrical guide portion is provided with grooves which run parallel or at an angle to the axis of the stopper and ventilate the space above the sealing ring or rings. 6. A hollow stopper according to any of the preceding claims, characterised in that the cylindrical portion carrying the sealing ring or rings has, immediately below the lowermost sealing ring a portion of larger diameter than above said lowermost sealing ring. 7. A hollow stopper according to any of the preceding claims, characterised in that the cylindrical portion carrying the sealing ring or rings, is conically tapered below the lowermost sealing ring. s. A hollow stopper according to any of the preceding ,claims,

characterised in that the hollow stopper is closed at the top.