baber/WOPTO huggingface dataset:
Patent FR-2589109-A1 (FR)
Title: Four-wheel-drive transmission device
Inventor: RENAUDIN ALAIN
IPC: B60K17/35
Filed: 1985-10-29
Abstract: Four-wheel-drive transmission device comprising at the output of a gearbox 55 two output shafts with their drive pinions 1, characterised in that the two drive pinions 1 respectively drive an intermediate crown wheel 2 which is eccentric with respect to the axis 8 of the front axle; the said intermediate crown wheel 2 drives a pinion 3 integral with an intermediate shaft 4 which is connected to the input of the central differential 5; one output of the central differential 5 drives a drive pinion 54 of the front axle, coaxial with the said pinion 3, which drives a crown wheel 11 integral with the front differential 6 and coaxial with the axis 8 of the front axle; and the other output of the central differential 5 drives a rear final-drive shaft 10 coaxial with the said pinion 3.
Patent FR-2599522-A1 (FR)
Title: Regulation system
IPC: F23N5/00
Filed: 1986-05-29
Abstract: a. System for regulating combustion with the aid of a zirconium probe. b. System characterised in that it comprises branches 4, 5, 6 having peak limiting elements 42, 52, 62 supplying a peak-limited signal S41, S42, S43 to a two-level +/- R comparator 8 and to a logic circuit 9. c. The invention relates to regulation of combustion.
Patent FR-2601619-A1 (FR)
Title: Device for rapidly changing extruder heads for coating cables
Inventor: ASTE ROBERT
IPC: B29C48/06
Filed: 1986-07-17
Abstract: The invention relates to a device making it possible simultaneously to change over extruder heads rapidly on an extruder and to prepare a head before this changeover so as to be able to put it into operation immediately. The device comprises a manipulation apparatus which is separate from the extruder and which includes a pivoting support 20 having a vertical axis and arranged to carry two heads (21 and 22) and to move them in horizontal and vertical translational movement. In addition, the apparatus is equipped with means (33, 37) for heating the extruder heads. The apparatus is preferably mounted on wheels 2 in order to allow the heads to be transported to a cleaning (maintenance) unit or storage unit. It may furthermore be robotised with a view to positioning the heads on the extruder automatically. The device can be used in cable-jacketing or cable-coating extrusion lines.
Patent FR-2586024-A1 (FR)
Title: Elements de matiere plastique rendus troubles
Inventor: HENNIG JURGEN
IPC: C08F212/08
Filed: 1986-07-29
Abstract: L'INVENTION CONCERNE DES ELEMENTS DE MATIERE PLASTIQUE RENDUS TROUBLES, CONTENANT UNE MATRICE DE POLYMERE DANS DES PROPORTIONS DE 1 A 30 EN POIDS PAR RAPPORT A LA MATRICE DE POLYMERE ET UN AGENT DE TROUBLE EN FORME DE PARTICULES, LES PERLES RETICULEES SE COMPOSANT D'UN POLYMERE QUI EST CONSTITUE POUR 9,9 A 59,9 EN POIDS D'UN OU PLUSIEURS MONOMERES A POLYMERISABLES PAR VOIE RADICALAIRE, QUI CONTIENNENT UN RADICAL AROMATIQUE OU DE MONOMERES NON AROMATIQUES A QUI CONTIENNENT UN HALOGENE, ET POUR 90 A 40 EN POIDS DE MONOMERES VINYLIQUES B COPOLYMERISABLES AVEC CES MONOMERES, MAIS DIFFERENTS DE CEUX-CI, ET POUR 0,1 A 20 EN POIDS D'AU MOINS UN MONOMERE RETICULANT V ET POUR 0 A 10 EN POIDS D'UN MONOMERE (FORTEMENT) POLAIRE H, SOUS RESERVE QUE: A.L'INDICE DE REFRACTION DU POLYMERE SOIT SUPERIEUR A CELUI DE LA MATRICE DE POLYMERE, ET QUE B.LA TAILLE MOYENNE DES PERLES SOIT DE 5 A 50MM.
Patent FR-2605133-A1 (FR)
Title: Multidirectional sound deflector
IPC: H04R1/34
Filed: 1986-10-08
Abstract: The present invention relates to sound deflectors which can be combined with loudspeakers. The deflector is essentially characterised in that it comprises a translucent upper panel 2 upon which two translucent panels 4 pivot vertically, two hinged arms 9, 10 freeing it from the outer relief 18 in the positioning plane 19 of the loudspeaker assembly 17, and two fastenings 12, 15 on this loudspeaker assembly on a vent-hole speaker. Application in particular to directing sound emitted by hi-fi car radio assemblies, after fastening the deflector onto these hi-fi assemblies, or on various speakers, inside a vehicle or outside a vehicle.
Patent FR-2607576-A1 (FR)
Title: Reflecteur pour vehicule automobile a fixation amelioree
Inventor: BLANCHETON LUCIEN
IPC: F21V17/00
Filed: 1986-11-27
Abstract: L'INVENTION CONCERNE UN REFLECTEUR POUR VEHICULE AUTOMOBILE A FIXATION AMELIOREE DU TYPE COMPRENANT DES ORGANES DE FIXATION OU REGLAGE MOULES D'UNE SEULE PIECE AVEC LE REFLECTEUR ET A L'EXTERIEUR DE L'ENVELOPPE DU QUADRIQUE DE REFLEXION UTILE. LE REFLECTEUR SELON L'INVENTION EST CARACTERISE PAR LE FAIT QUE LES PLANS DE TRONCATURE 2, 3 DU QUADRIQUE REFLECHISSANT 1 SONT PROLONGES A LEURS INTERSECTIONS PAR DES PATTES 4 D'EPAISSEUR SENSIBLEMENT EGALE A CELLE DES PLANS DE TRONCATURE 2, 3 ET FORMANT DEUX A DEUX UNE CORNIERE 5 DE SUPPORT D'UN MOYEN DE FIXATION OU DE REGLAGE 6 VENU DE MOULAGE AVEC LE REFLECTEUR 1, 2, 3 ET LESDITES PATTES 4. APPLICATION A L'INDUSTRIE AUTOMOBILE.
Patent FR-2608454-A1 (FR)
Title: Aqueous dialkyl disulphide emulsions, process for preparation and use
Inventor: GROSSOLEIL JACQUES
IPC: C09K23/00
Filed: 1986-12-23
Abstract: Stable aqueous dialkyl disulphide emulsions with monodisperse droplets from 0.1 to 2  mu m in average diameter. They are obtained by reaction, with stirring, at a temperature of between 40 and 90  DEG C, of an aqueous solution of sodium hydroxide and of an alkylthiol in which the alkyl radical contains from 2 to 18 carbon atoms in the presence of at least one water-soluble radical initiator. They can be employed especially for the recovery of compounds with partitioned solubility, which are dispersed and/or dissolved in an aqueous medium, and for the preparation of emulsions of the said compounds.
Patent FR-2612383-A1 (FR)
Title: Device for extending a fixed top supported by the table top
Inventor: CHARPENTIER LUC
IPC: A47B1/05
Filed: 1987-03-16
Abstract: Device for extending a fixed top supported by the table top. The invention relates to a device making it possible to build in an extension under a top without detaching the top from its support. It consists of a system of connecting rods 2 formed into a parallelogram positioned on a sliding assembly intended to retract or extend the system under the top. The system of connecting rods 2 is extended by a lug 3 which surrounds a stop-piece 4 in order to reach the upper level of the extension-receiving top or which disengages from the stop-piece 4 in order to arrange the extension on the slide system at the lower level of the top, enabling the extension to be stored under the top. The device according to the invention is particularly intended for the extension, by means of an extension or slide, of a top of any shape whatsoever.
Patent FR-2617205-A1 (FR)
Inventor: BOUSSAND JACQUES
IPC: D03D15/12
Filed: 1987-06-26
Abstract: Openwork flame-resistant coated fabric made of core threads coated with a flame-resistant plasticised PVC sheath. The core thread is a vinylal thread. 1 Application: openwork flame-resistant coated fabrics for premises to which the public is admitted.
Patent FR-2619665-A1 (FR)
Title: Dispositif de commande de l'eclairage de locaux
Inventor: DELAHAYE JEAN YVES
IPC: H05B37/02
Filed: 1987-08-21
Abstract: Ce dispositif comprend un premier ensemble 100 constitué par une minuterie, un circuit de déclenchement, un bouton-poussoir BP et des contacts permettant d'enclencher la minuterie. Ce dispositif est caractérisé par le fait qu'il comprend un ensemble autonome 200 comprenant un détecteur de type pyroélectrique 30, un circuit d'alimentation 40 relié aux bornes a, b du circuit de déclenchement de la minuterie, un circuit électronique 50 permettant d'amplifier le signal délivré par le détecteur et de délivrer une impulsion de tension calibrée capable de commander un relais 60 qui ferme un contact 62 lequel est connecté en parallèle sur les bornes a, b. Application à l'éclairage de locaux dans des immeubles.
Patent FR-2620910-A1 (FR)
Title: Key ring, particularly for car keys
IPC: G04B47/00
Filed: 1987-09-25
Abstract: The invention relates to a key ring, particularly for car keys, comprising a ring integral with a case in which the various keys are attached. This key ring is characterised in that the case 3 includes a compartment 5 for storing and dispensing coins 6, this compartment 5 being connected to a memorising device ensuring the recording of a number of pulses corresponding to the coins 6 removed from the case 3 and controlling the operation of the regulator (minute wheel) of a quartz watch or of a watch of the electro-mechanical type 7 connected to a device 8 for audible signalling. The invention relates to objects for personal use and travel articles and, more particularly, to the key ring industry.
Patent FR-2621643-A1 (FR)
Inventor: DIEMERT JEAN-MARC
IPC: E06B3/58
Filed: 1987-10-13
Abstract: The present invention relates to a security profile (1, 4) for metal frames intended for a security filling (2) and comprising a cover strip (5) for fixing the said filling (2). Profile characterised in that the cover strip (5) has, on the one hand, two supports (10, 11) interacting with the profile (1), forming a line substantially perpendicular to an attack force and combining so as to resist a thrust (F) transmitted to the cover strip (5) and, on the other hand, a third support (12) simultaneously forming a catch, independent of the two first supports (10, 11) and not forming part of their possible deformation, offering, during attack, additional resistance to the thrust and to the tilting of the cover strip (5) out of its housing (8) in the profile (1, 4).
Patent FR-2622285-A1 (FR)
Title: Systeme de controle des deplacements angulaires d'un plateau tournant et application a un spectrometre a rayons x
Inventor: BISARO RENE
IPC: G01B9/02
Filed: 1987-10-21
Abstract: L'invention concerne un système de contrôle de la rotation d'un plateau tournant T1 comportant un interféromètre dont les bras de mesure sont réalisés avec des trièdres en forme de coins de cubes en verre P1, P2 fixés sur le plateau tournant T1 et permettant pour des faibles rotations du plateau T1 de réfléchir toujours dans la même direction la lumière qu'ils reçoivent d'une source S2. Une lame biréfringente LB est placée dans l'un des bras et deux récepteurs R1, R2 recevant par des analyseurs A1, A2 la lumière fournie par l'interféromètre permettent de détecter des déplacements des coins de cubes P1, P2 donc des rotations du plateau T2. L'invention est appliquée à un spectromètre à rayons X.
Patent FR-2622297-A1 (FR)
Title: Method for determining the speed of propagation of a fluid such as air, water, etc., and device for implementing the method
IPC: G01P5/00
Filed: 1987-10-26
Abstract: The present invention relates to methods for determining at least one parameter of displacement of a fluid with respect to a given reference frame, as well as means for implementing the said methods. The method according to the invention, with its means of implementation, is especially characterised in that it consists in imparting to a vehicle 4 a displacement in the fluid 3 along a predetermined trajectory 1, 6, so that at at least one point, the direction of the trajectory makes a non-zero angle with that of the displacement of the fluid, and in determining, with respect to the reference frame 2, a set of positions of the vehicle when it passes, on its displacement trajectory, over the previously mentioned point. Application to determining, in particular, the wind speed in regions of the atmosphere which are distant from the measurement station.
Patent FR-2605908-A1 (FR)
Title: Cylindre de laminoir a pas de pelerin pour la fabrication de tubes
Inventor: COOK CHARLES SEAMAN
IPC: B21B27/02
Filed: 1987-10-30
Abstract: CE CYLINDRE DE LAMINOIR A PAS DE PELERIN EST UNE PIECE 1 ANNULAIRE, CONSTITUEE D'AU MOINS DEUX PARTIES 9, 11 EN ACIERS ALLIES DIFFERENTS, A SAVOIR UNE PARTIE EXTERIEURE 9 AVEC UNE GORGE 5, FORMEE DANS LA PERIPHERIE EXTERIEURE DE CETTE PARTIE DONT L'EPAISSEUR EST PLUS GRANDE QUE LA PROFONDEUR DE LA GORGE ET QUI EST EN ACIER ALLIE DURCI PAR SA TRANSFORMATION EN MARTENSITE, ET UNE PARTIE INTERIEURE 11, SENSIBLEMENT PLUS EPAISSE QUE LA PARTIE EXTERIEURE ET CONSTITUEE EN UN ACIER INCAPABLE D'ETRE DURCI PAR LA TRANSFORMATION MARTENSITIQUE DANS LES CONDITIONS DE TRAITEMENT THERMIQUE UTILISEES POUR DURCIR LA PARTIE EXTERIEURE. LA PIECE ANNULAIRE PEUT INCLURE UNE PARTIE ADDITIONNELLE, LA PLUS INTERNE, DURCIE PAR SA TRANSFORMATION EN MARTENSITE DANS LESDITES CONDITIONS DE TRAITEMENT THERMIQUE. APPLICATIONS : FABRICATION DE TUBES POUR BARRES DE COMBUSTIBLE NUCLEAIRE.
Patent FR-2607032-A1 (FR)
Title: Laminoir, en particulier laminoir a froid
Inventor: WITTING ERHARD
IPC: B21B31/30
Filed: 1987-11-19
Abstract: L'INVENTION CONCERNE UN LAMINOIR, EN PARTICULIER UN LAMINOIR A FROID, DE PREFERENCE POUR DES MATERIAUX METALLIQUES OU DES METAUX, PRINCIPALEMENT DE L'ACIER OU DES NON-FERREUX LOURDS, AVANTAGEUSEMENT POUR LAMINER, OU PRE-LAMINER OU RELAMINER DES BANDES OU DES TOLES, AVEC AU MOINS DEUX, OU MIEUX QUATRE A DIX, CYLINDRES DISPOSES LES UNS AU-DESSUS DES AUTRES. SUIVANT L'INVENTION, LE PLAN DE SYMETRIE S, SPECIALEMENT VERTICAL, DE LA CONSTRUCTION PORTEUSE DU LAMINOIR OU DE LA CAGE OU DES COLONNES DU LAMINOIR, SPECIALEMENT DE SA CHARPENTE PORTEUSE PRINCIPALE 19, 20, 21, 22, PREVUE AVEC UNE FENETRE AU MOINS DANS LA ZONE DU BOMBE DES CYLINDRES OU DE L'INTERVALLE DE LAMINAGE, COINCIDE AVEC LE PLAN DE SYMETRIE S DU SYSTEME DE CYLINDRE 1 A 10 OU DE LA DISPOSITION DES CYLINDRES, SPECIALEMENT VERTICAL, SOIT TOTALEMENT OU AU MOINS ESSENTIELLEMENT, ET EST DONC TOURNE DE 90 PAR RAPPORT A L'EXECUTION TRADITIONNELLE.
Patent FR-2627419-A1 (FR)
Inventor: FREYWISS ERIC
IPC: B25J19/06
Filed: 1988-02-23
Abstract: PCT No. PCT/FR89/00031 Sec. 371 Date Oct. 17, 1989 Sec. 102(e) Date Oct. 17, 1989 PCT Filed Jan. 30, 1989 PCT Pub. No. WO89/08012 PCT Pub. Date Sep. 8, 1989.In a multi-axis mechanical manipulator with adjustable travel and protection against overloading. The movement is transmitted to the indexing mechanism (10) by the combination of a sliding rotor motor (2) of a reducing gear with wheel and endless screw (30) and an adjustable torque limiter (40). The law of motion of the indexing mechanism (10) is determined in this way so as to obtain constant speed over a wide range, possibly with stopping points. The rotating frame (56) is linked to the indexing mechanism (10) by a spring bushing (50). The movement is transmitted to the cylindrical cam (6) by an adjustable torque limiter (28). The manipulating arm (7) is displaced by a spring plate which permits a momentary angular retraction of the arm (7) when it encounters an obstacle. The present invention may be used for the handling of loads or parts.
Patent FR-2634041-A1 (FR)
Title: Device for remote triggering and control of any electrical, electronic or other apparatus
IPC: H04M11/00
Filed: 1988-07-06
Abstract: a) The invention relates to a device for remotely triggering any electrical or other apparatus. b) Remote triggering and control device characterised by an electronic changeover switch 1 controlled by the peak-to-peak voltage supplied during the transmission of an item of call information by the telecommunication network 2, including a set of connected electronic means which consist of a bistable relay 3 equipped with a memory 4 associated with a time delay, and the memory 4 is preceded by a network interface 5 fitted with a protection transformer equipped with electronic means 6 so as to recognise and process one or more required selective information items. The assembly is powered at low voltage, is equipped with another transformer so as to have available one or more selective low-voltage outputs and one or more selective mains voltage outputs for allowing one or more appliances to be put into use. The assembly is fitted with a simulation test means. c) The invention applies in general to the remote monitoring and triggering of any apparatus.
Patent FR-2624035-A1 (FR)
Title: Procede de fabrication d'un transfert de flocons multicolores et articles textiles obtenus par ce procede
Inventor: ABRAMS LOUIS BROWN
IPC: D06Q1/14
Filed: 1988-08-24
Abstract: Procédé de fabrication d'un transfert de flocons multicolores caractérisé en ce qui consiste à : - Imprimer un adhésif détachable ou libérable sur une feuille de base, - Réaliser un flocage de façon séquentielle, de flocons de couleurs différentes au travers d'une section ouverte d'une barrière dans l'adhésif de manière à former une pluralité de configurations de couleurs uniques prédéterminées disposées de manière à constituer un dessin prédéterminé et, - Appliquer un adhésif de liaison sur les extrémités libres desdits flocons.
Patent FR-2622746-A1 (FR)
Title: Appareil concu pour enlever les gaines et le revetement de cables en fibre de verre
IPC: G02B6/245
Filed: 1988-09-27
Abstract: Cet appareil comporte deux mâchoires 1, 2 adaptées pour former un corps creux en se refermant et où l'on peut introduire un câble en fibre de verre destiné à être dénudé. Les mâchoires comportent, à une extrémité, des lames 10, 11 internes montées sur des porte-lames formant ressorts 8, 9 et adaptées pour enlever le revêtement d'une fibre de verre et, à l'autre extrémité, des couteaux 12, 13, qui se font face, qui sont situés obliquement par rapport à l'axe du corps creux et dont les bords de coupe 15, 16 sont profilés pour faire des coupes circulaires 17, 18 permettant d'enlever les gaines d'un cable en fibre de verre. Dans la zone de ces couteaux 12, 13 sont prévues des parties saillantes 19, 20, du type réceptacle, l'une 19 étant sous forme de corps creux incorporant une lame profilée 22 et l'autre 20 étant pourvue d'un bec 23 agencé pour se placer devant la lame 22 lorsque les mâchoires 1, 2 sont refermées.
Patent FR-2636962-A1 (FR)
Title: Process and device for removing yeast from wine
Inventor: ANDRE JEAN CLAUDE
IPC: G01N33/14
Filed: 1988-09-28
Abstract: The invention relates to a process and a device for regulating the concentration of a slurry from the removal of yeast from a wine at the outlet of a fermenter 1, comprising a centrifuge 3 with an outlet nozzle 6 for the yeast-removal slurry and coming from the fermenter 1 a feed pipe 2 provided with a valve means 4 for adjusting the concentration of the slurry in the outlet nozzle 6. The device according to the invention comprises, in addition, a concentration sensor 20 fed with slurry from the nozzle 6 where an incident light beam 14 penetrates and comprising one end 16, immersed in the slurry, of the optical fibre 15 forming a collimator for a beam diffused from the incident beam 14, the other end 17 of the fibre 15 illuminating an optoelectronic transducer 30 coupled by automatic control means 35 to the said valve means 4. Preferably, the incident beam 14 is derived from a He-Ne laser 11 emitting on 632.8 nm.
Patent FR-2638347-A1 (FR)
Title: Lifting system for the seat ring of a toilet pan
IPC: A47K13/10
Filed: 1988-10-28
Abstract: Device for raising the seat ring 2 of a toilet pan 1, possessing: - a seat ring 2 attaching device 4 and, at each end of said rod 53, two fixing means 51 and 52 pressing on the inside edge 2b and outside edge 2c respectively of the seat ring 2; - an electric actuator 6 connected at one end to the seat ring attaching device via a rotational connection part 58, and at the other fixed to the floor by a fixing part 67 pivoting about a horizontal axis; - an electric circuit 7 for operating the actuator; and - a mechanical device 8 for turning the circuit on.
Patent FR-2628480-A1 (FR)
Title: Procede et dispositif pour sa mise en oeuvre, pour surveiller un arret de securite dans des moteurs a combustion interne
Inventor: BERGER JOACHIM
IPC: F02D41/22
Filed: 1989-01-19
Abstract: Procédé caractérisé en ce que la vérification du fonctionnement de la soupape d'arrêt de sécurité 16 au moment de la libération de la quantité de carburant de démarrage s'effectue par l'intermédiaire de l'appareil de commande 10 et en ce que pour sa mise en oeuvre, il est prévu un circuit de vérification 19, ce circuit commandant la soupape électromagnétique d'arrêt de sécurité 16 pour interrompre la poursuite de l'alimentation en carburant, si les injections s'effectuent par exploitation de signaux en retour.
Patent FR-2643080-A1 (FR)
Inventor: LABARRE JEAN-FRANCOIS
IPC: C07F9/6593
Filed: 1989-02-10
Abstract: The invention concerns oxodiaminocyclotriphosphazene compounds useful for their immunomodulatory, antitumoral properties, of general formula (I), where R1, R2, R3, R4, R5, R6 independtly of each other may denote a halogen or R1 and R2, R3 and R4, R5 and R6 or R1 and R3 independently of each other denote at least one chain of formula (II): -NR-[(CH)2n-O[p-(CH2)m-NR'- where R and R' indepe ndently of each other denote hydrogen or a C1-14 alkyl group and n, m and p are integers between 1 and 10, whereby n may have different values in the alkyloxy chain formed, provided that when R1 and R3 denote a chain of formula (II) and m = n = 2, then p is not equal to 1 if R = R' = H. The invention also concerns the methods of preparation of these compounds and their applications.
Patent FR-2643008-A1 (FR)
IPC: A23N7/02
Filed: 1989-02-13
Abstract: A device for obtaining fruit or vegetables having facets of given profile consists of a tubular casing (1) provided with slits (3 to 6) which guide cutting means such as piano strings. An internal or external mobile crown moves the cutting means (9, 10) longitudinally. The invention also concerns an industrial installation in which such a device is used.
Patent FR-2643299-A1 (FR)
Title: Procede pour encastrer des poils metalliques dans un element de base
Inventor: UEDA HIROSHI
IPC: B32B15/16
Filed: 1989-02-22
Abstract: On décrit un procédé pour encastrer des poils métalliques. Un adhésif 2 est appliqué par revêtement à un élément de base 1, et des poils métalliques 4 sont encastrés électriquement dans le revêtement adhésif. Une soudure sous forme de poudre ou de granules est incorporée à l'avance dans l'adhésif afin de fixer les poils encastrés à l'élément de base lorsqu'elle est soumise à une opération de fusion.
Patent FR-2629796-A1 (FR)
Title: Package for personal care objects and method of packaging personal care products
IPC: A45D40/00
Filed: 1989-04-07
Abstract: The invention relates to a package for personal care products. </H0> It comprises several separate containers 12, 14, 16, 18 each filled with a quantity of care product and each having, in cross-section, the shape of a truncated triangular wedge. The containers can be assembled together in a detachable manner by means of strips 42, 46 of the "Velcro" type in order to form together a compact block with a cross-section which is square or of long flattened shape. Field of application: transport of daily personal care and toiletry products for travelling, etc.
Patent FR-2645462-A1 (FR)
Inventor: VENTAVOLI ROGER
IPC: B22D11/20
Filed: 1989-04-06
Abstract: The invention relates to a method and an apparatus for obtaining thin metal products by continuous casting. The device comprises an ingot mould 2 and pinch rolls 6, 6' intended to cause, by reduction of the thickness of the said product, the closure of the solidification pool. The separation force F exerted on the pinch rolls by the product is measured, and to the core of the still molten product is applied, by means of inductors 8, 8' housed in the pinch rolls or upstream of the latter, a variable magnet field slaved by slaving means 9 to the said separation force so that the latter does not exceed, on a long- term basis, an upper limit value given in advance which represents the stress which can be tolerated momentarily by the pinch rolls without damage.