FR2586098A1 - Device for monitoring the elongation under tension of a bolt - Google Patents

Device for monitoring the elongation under tension of a bolt Download PDF

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Publication number
FR2586098A1
FR2586098A1 FR8512114A FR8512114A FR2586098A1 FR 2586098 A1 FR2586098 A1 FR 2586098A1 FR 8512114 A FR8512114 A FR 8512114A FR 8512114 A FR8512114 A FR 8512114A FR 2586098 A1 FR2586098 A1 FR 2586098A1
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FR
France
Prior art keywords
elongation
bolt
stud
pressure
monitoring
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
FR8512114A
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French (fr)
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FR2586098B1 (en
Inventor
Yves Godrie
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EG&G Sealol Inc
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EG&G Sealol Inc
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Publication date
Application filed by EG&G Sealol Inc filed Critical EG&G Sealol Inc
Priority to FR8512114A priority Critical patent/FR2586098B1/en
Publication of FR2586098A1 publication Critical patent/FR2586098A1/en
Application granted granted Critical
Publication of FR2586098B1 publication Critical patent/FR2586098B1/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23PMETAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
    • B23P19/00Machines for simply fitting together or separating metal parts or objects, or metal and non-metal parts, whether or not involving some deformation; Tools or devices therefor so far as not provided for in other classes
    • B23P19/04Machines for simply fitting together or separating metal parts or objects, or metal and non-metal parts, whether or not involving some deformation; Tools or devices therefor so far as not provided for in other classes for assembling or disassembling parts
    • B23P19/06Screw or nut setting or loosening machines
    • B23P19/067Bolt tensioners
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B25HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25BTOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FOR FASTENING, CONNECTING, DISENGAGING OR HOLDING
    • B25B23/00Details of, or accessories for, spanners, wrenches, screwdrivers
    • B25B23/14Arrangement of torque limiters or torque indicators in wrenches or screwdrivers
    • B25B23/145Arrangement of torque limiters or torque indicators in wrenches or screwdrivers specially adapted for fluid operated wrenches or screwdrivers
    • B25B23/1456Arrangement of torque limiters or torque indicators in wrenches or screwdrivers specially adapted for fluid operated wrenches or screwdrivers having electrical components
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01LMEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L5/00Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
    • G01L5/24Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for determining value of torque or twisting moment for tightening a nut or other member which is similarly stressed

Abstract

The invention relates to the field of screw and bolt clamping apparatus. The device for monitoring and automatically controlling the elongation of a bolt 1 with respect to a gauge rod 2 is essentially characterised in that it comprises a sensor with feelers 6, 7 respectively on the adjacent ends 4, 5 of the said gauge rod and the said bolt, whose output is connected to a processing unit 17 in which there is introduced the set-point value of an elongation and a pressure not to be exceeded, the said unit constituting the control member of the means 11 for releasing and isolating a tension cylinder. Application to precision clamping apparatuses.

Description

La présente invention concerne un dispositif de contrôle et d'asservissement d'allongement de goujon soumis à une traction, applicable en particulier au serrage précision et de sécurité en boulonnerie. The present invention relates to a device for controlling and controlling the elongation of studs subjected to traction, applicable in particular to precision and safety tightening in bolting.

Dans ce domaine par exemple, on sait que l'on peut effectuer un serrage précis en procédant à un allongement préalable du boulon par traction mécanique afin d'amener manuellement l'écrou en appui sur la surface à serrer, tout en effectuant une mesure en continu dudit allongement afin de l'interrompre automatiquement lorsqu'une valeur prédéterminée est atteinte.La Demanderesse a d'ailleurs décrit un tel procédé et un dispositif de mise en oeuvre dans sa demande de brevet français en cours NO 85 05 892 déposé le 18 Avril 1985 sous le titre "Procédé et dispositif de serrage de boulonnerie", où il est en particulier proposé un capteur de mesure de l'ellcngement, disposé sur l'extrémité du goujon dont il détecte la distance par rapport à une pige fixe prenant appui au fond du boulon, par l'intermédiaire d'une variation de courants de Foucault. Ce capteur est relié à un circuit de commande automatique de mise en pression, de stabilisation et de relachement de ladite pression sur un vérin de type annulaire d'allongement du goujon. Un tel capteur s'avère efficace et précis mais toutefois son prix de revient relativement élevé limite sa mise en oeuvre systématique. In this field, for example, we know that precise tightening can be carried out by proceeding with a prior elongation of the bolt by mechanical traction in order to manually bring the nut to bear on the surface to be tightened, while performing a measurement in continuous said extension in order to automatically interrupt it when a predetermined value is reached. The Applicant has moreover described such a method and an implementation device in its pending French patent application NO 85 05 892 filed on April 18 1985 under the title "Method and device for tightening bolts", where there is in particular a sensor for measuring the ellcngement, placed on the end of the stud whose distance it detects with respect to a fixed rod bottom of the bolt, through a variation of eddy currents. This sensor is connected to an automatic control circuit for pressurizing, stabilizing and releasing said pressure on an annular type cylinder for extending the stud. Such a sensor proves to be efficient and precise, but nevertheless its relatively high cost price limits its systematic implementation.

La présente invention vise donc à remédier à cet inconvénient, en fournissant un dispositif de contrôle et d'asservissement d'allongement, applicable notamment en boulonnerie, et plus généralement dans tous les cas où une traction doit être effectuée avec haute précision et gardes de sécurité, ledit dispositif comportant des organes automatiques faciles à mettre en oeuvre. The present invention therefore aims to remedy this drawback, by providing a control and elongation control device, applicable in particular in bolting, and more generally in all cases where traction must be carried out with high precision and security guards , said device comprising automatic members that are easy to implement.

Conformément à l'invention, le dispositif de contrôle et d'asservissement de l'allongement, associé à un vérin de traction à pression de fluide et à un organe de mesure d'allongement par rapport à une pige fl, mnrend un capteur à palpeurs respectivement sur les extrémités adjacentes de la pige et du goujon, dont la sortie est reliée à une centrale de mesure, elle-même reliée à une unité de traitement dans laquelle est introduite la valeur d'un allongement et d'duc pression de consigne à ne pas dépasser, ladite unité constituant l'organe de commande du moyen de déclenchement et d'isolation dudit vérin. In accordance with the invention, the elongation control and servo device, associated with a fluid pressure traction cylinder and a member for measuring elongation with respect to a rod f, includes a probe sensor. respectively on the adjacent ends of the rod and of the stud, the output of which is connected to a central measurement unit, itself connected to a processing unit into which the value of an elongation and of the reference pressure at do not exceed, said unit constituting the control member of the triggering and isolation means of said cylinder.

Suivant d'autres caractéristiques, les capteurs sont du type à palpeur mécanique et le moyen de commande du vérin est une électro-vanne, l'ensemble capteurs-centrale de mesure étant d'un type permettant une scrutation rapide devant la vitesse de montée en pression du vérin. According to other characteristics, the sensors are of the mechanical feeler type and the actuator control means is a solenoid valve, the sensor-measurement unit assembly being of a type allowing rapid scanning before the rate of rise in cylinder pressure.

D'autres caractéristiques et avantages de l'invention ressortiront mieux de la description qui va suivre, faite en regard des dessins annexés sur lesquels :
la figure 1 représente un schéma synoptique de l'en- semble du dispositif selon l'invention ; et
la figure 2 représente un graphique illustrant le fonctionnement du dispositif, en particulier sa sécurité.
Other characteristics and advantages of the invention will emerge more clearly from the description which follows, given with reference to the appended drawings in which:
FIG. 1 represents a block diagram of the assembly of the device according to the invention; and
FIG. 2 represents a graph illustrating the operation of the device, in particular its security.

Comme mentioné plus haut, l'objet du dispositif selon l'invention est de réaliser un asservissement de l'allongement d'un goujon soumis à un effort de traction. Dans le cadre général de l'allongement à la traction d'un goujon métallique, cet asservissement permet de toute façon de ne pas dépasser la limite élastique du métal et, en deçà, de respecter une valeur prédéterminée. As mentioned above, the object of the device according to the invention is to provide a control of the elongation of a stud subjected to a tensile force. In the general context of the tensile elongation of a metal stud, this control makes it possible in any case not to exceed the elastic limit of the metal and, below, to respect a predetermined value.

En se référant à la figure 1, un goujon 1 est muni de manière connue en soi d'une pige intérieure 2 dont une extrémité est au niveau 3 de l'extrémité correspondante dudit goujon. Les extrémités opposées adjacentes respectives 4 et 5 de la pige et du goujon sont munies chacune d'un capteur à palpeur mécanique 6 et 7 respectivement, dont la sortie est reliée à une centrale de mesure 8. Un organe assurant l'allongement du goujon 1, tel qu'un vérin hydraulique 9, dont la partie mobile est solidarisée à l'extrémité 5 du goujon 1, est alimenté par un conduit 10 comprenant une électro-.  Referring to Figure 1, a stud 1 is provided in a manner known per se with an inner rod 2, one end of which is at level 3 with the corresponding end of said stud. The respective adjacent opposite ends 4 and 5 of the rod and the stud are each provided with a sensor with mechanical feeler 6 and 7 respectively, the output of which is connected to a central measurement unit 8. A member ensuring the elongation of the stud 1 , such as a hydraulic cylinder 9, the movable part of which is secured to the end 5 of the stud 1, is supplied by a conduit 10 comprising an electro-.

11, un régulateur de pression-amont 12 et une pompe d'alimentation convenable 13.11, an upstream pressure regulator 12 and a suitable supply pump 13.

Le régulateur 12 est relié à lå centrale de mesure 8, par la ligne 14, tandis que l'électro-vanne 11 et la pompe 13 sont reliés par les lignes respectives 15 et 16 à une unité de traitement 17. -Celle-ci comprend un organe 18 d'introductien et d'affichage de données en entrée et sortie, par exemple à clavier et imprimante, et elle est en outre relié e à la centrale de mesure 8. The regulator 12 is connected to the central measurement unit 8, by the line 14, while the solenoid valve 11 and the pump 13 are connected by the respective lines 15 and 16 to a processing unit 17. -This comprises a member 18 for input and display of input and output data, for example with a keyboard and printer, and it is also connected to the measurement unit 8.

Il est évident que le dispositif tel que décrit cidessus pour un seul goujon s'applique normalement à un nombre quelconque de goujons et qu'il suffit dans ce cas de prévoir en conséquence la capacité de la centrale 8 et de l'unité 17, ainsi que le nombre nécessaire de capteurs, de vérins et d'électro-vannes.  It is obvious that the device as described above for a single stud normally applies to any number of studs and that it is sufficient in this case to provide accordingly the capacity of the control unit 8 and of the unit 17, as well than the necessary number of sensors, cylinders and solenoid valves.

Pour le fonctionnement, les palpeurs des capteurs 6 et 7 sont amenés préalablement au contact respectif de la pige et du goujon. On introduit lesvaleurs consignes de déclenchement et de sécurité en 18, qui comprennent essen -tiellement la longueur d'allongement optimal et une pression limite du fluide d'alimentation du vérin. Après introduction de ces données, on vérifie la valeur différentielle initiale entre les deux capteurs, ce qui correspond à une mise à zéro de l'ensemble. le déclenchement de la montée en pression est alors effectué et, simultanément, le contrôle en temps réel débute.Le type de capteur est choisi de telle sorte que
la vitesse de scrutation soit suffisamment élevée par rapport à la vitesse de montée en pression pour permettre te déclenchement d'arrêt ou l'isolation du vérin par l'électro- vanne, au micron de longueur d'allongement près,
Le fait de disposer d'organes de mesure de valeurs de consigne en longueur d'allongement et en pression de fluide, lesdites valeurs étant introduites préalablement d. " l'unité de traitement, permet au dispositif selon l'invention a rer une double sécurité : l'isolation du vérin de tractif est en effet réaliséelorsque l'une ou l'autre de la longueur limite ou de la pression limite est atteinte.Cette double sécurité est illustrée par le graphique de la figure 2, où l'on a porté le temps Q er. abscisseset la pression P ou l'allongement A en ordonnées. On peut par exemple fixer une pression de consigne p évoluant selon la courbe I et un allongement maximal a selon la courbe II, inférieure à une valeur de sécurité S. L'isolation du vérin se traduit par les paliers respectifs des courbes I et IT au temps t et elle interviendrait aussi bien en fonction de l'allongement que de la pression. Par contre, si la pression maximale PM était prédéterminée à une valeur trop élevée, ltisolation serait assurée par la valeur a de l'allongement. Inversement, un allongement prédéterminé de valeur trop élevée ne serait pas atteint pour une pression prédéterminee correcte.
For operation, the sensors of sensors 6 and 7 are brought beforehand into the respective contact of the rod and the stud. The trigger and safety set point values are introduced at 18, which essentially comprise the optimal length of elongation and a limit pressure of the actuator supply fluid. After entering this data, the initial differential value between the two sensors is checked, which corresponds to zeroing of the assembly. the pressure build-up is then triggered and, at the same time, real-time monitoring begins. The type of sensor is chosen so that
the scanning speed is high enough compared to the pressure build-up speed to allow the shutdown to be triggered or the actuator to be isolated by the solenoid valve, to the nearest micron of elongation length,
The fact of having set point measurement members in elongation length and in fluid pressure, said values being introduced beforehand d. "The processing unit allows the device according to the invention to provide double security: the isolation of the tractor cylinder is in fact achieved when either of the limit length or the limit pressure is reached. This double safety is illustrated by the graph in FIG. 2, where the time Q er has been plotted on the abscissa and the pressure P or the elongation A on the ordinate, for example a set pressure p evolving along the curve I and a maximum elongation a according to curve II, less than a safety value S. The isolation of the jack results in the respective stages of curves I and IT at time t and it would intervene as well according to the elongation as On the other hand, if the maximum pressure PM were predetermined at a too high value, the insulation would be ensured by the value a of the elongation. Conversely, a predetermined elongation of too high value would not be achieved for a correct predetermined pressure .

A titre d'exemple non limitatif, on peut réaliser selon l'invention un dispositif répondant aux possibilités suivantes en ce qui concerne l'allongement
- valeurs de consigne : déclenchement : 125 microns
sécurité : 150 microns
- (valeur différentielle : 318 microns)
- allongement maximal : 130 microns
- allongement résiduel : 126 microns.
By way of nonlimiting example, a device can be produced according to the invention which meets the following possibilities with regard to the elongation
- set values: tripping: 125 microns
security: 150 microns
- (differential value: 318 microns)
- maximum elongation: 130 microns
- residual elongation: 126 microns.

Il est bien entendu que la présente invention n' a été décrite et représentée qu'à titre explicatif mais nulle- ment limitatif et qu'on pourra y apporter toute modification utile. notamment dans le domaine des équivalences techniques, sans sortir de son cadre.  It is understood that the present invention has only been described and shown for explanatory purposes but is in no way limitative and that any useful modification may be made to it. especially in the field of technical equivalences, without going outside its scope.

Claims (3)

REVEINDICATIONS  REVEINDICATIONS Dispositif de contrôle et d'asservissement d'allongement de goujon soumis à un effort de traction par un vérin (9) à pression de fluide par l'intermédiaire d'un organe de mesure d'allongement dudit goujon (i), par rapport à une pige (2), caractérisé par le fait qu'il comprend un capteur à palpeurs (6, 7) respectivement sur les extrémités adjacentes (4, 5) de ladite pige et dudit goujon, dont la sortie est reliée à une centrale de mesure (8) elle-même reliée à une unité de traitement (17) dans laquelle est introduite la valeur d'un allongement et d'une pression de consigne à ne pas dépasser, ladite unité constituant l'organe de commande du moyen (11) de déclenchement et d'isolation dudit vérin. Device for controlling and controlling the elongation of studs subjected to a tensile force by a jack (9) at fluid pressure by means of a member for measuring elongation of said stud (i), with respect to a rod (2), characterized in that it comprises a sensor with probes (6, 7) respectively on the adjacent ends (4, 5) of said rod and of said stud, the output of which is connected to a measurement unit (8) itself connected to a processing unit (17) into which is entered the value of an elongation and a set pressure not to be exceeded, said unit constituting the control member of the means (11) triggering and isolation of said cylinder. 2. Dispositif selon la revendication 1, caractérisé par le fait que les capteurs (6, 7) sont du type à palpeur mécanique. 2. Device according to claim 1, characterized in that the sensors (6, 7) are of the mechanical feeler type. 3. Dispositif selon l'une des revendications 1 ou 2, carantçrisé par le fait que les capteurs et la centrale de mesure sont d'un type permettant une scrutation rapide devant la vitesse de montée en pression du vérin.  3. Device according to one of claims 1 or 2, characterized by the fact that the sensors and the measurement unit are of a type allowing rapid scanning before the speed of pressure build-up of the jack.
FR8512114A 1985-08-07 1985-08-07 DEVICE FOR MONITORING DRAW TENSIONING Expired - Fee Related FR2586098B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
FR8512114A FR2586098B1 (en) 1985-08-07 1985-08-07 DEVICE FOR MONITORING DRAW TENSIONING

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FR8512114A FR2586098B1 (en) 1985-08-07 1985-08-07 DEVICE FOR MONITORING DRAW TENSIONING

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FR2586098A1 true FR2586098A1 (en) 1987-02-13
FR2586098B1 FR2586098B1 (en) 1990-07-20

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2871231A1 (en) * 2004-06-02 2005-12-09 Skf Ab METHOD FOR CONTROLLING THE TENSIONING OF A ROD, OF THE TYPE OF SCREW OR ASSEMBLY PIN, AND DEVICE FOR IMPLEMENTING SUCH A METHOD
WO2008025922A2 (en) * 2006-09-01 2008-03-06 Aktiebolaget Skf Process and device for setting up and controlling a hydraulic chucking of one or a plurality of bolts

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1908936A1 (en) * 1969-02-22 1970-09-10 Licentia Gmbh Device for measuring the elongation of a bolt
JPS57143616A (en) * 1981-03-03 1982-09-04 Nippon Koki:Kk Condition controller for pc steel wire

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1908936A1 (en) * 1969-02-22 1970-09-10 Licentia Gmbh Device for measuring the elongation of a bolt
JPS57143616A (en) * 1981-03-03 1982-09-04 Nippon Koki:Kk Condition controller for pc steel wire

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENTS ABSTRACTS OF JAPAN, vol. 6, no. 245 (P-159)[1123], 3 décembre 1982; & JP - A - 57 143 616 (NIHON KOUKI K.K.) 04-09-1982 *

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2871231A1 (en) * 2004-06-02 2005-12-09 Skf Ab METHOD FOR CONTROLLING THE TENSIONING OF A ROD, OF THE TYPE OF SCREW OR ASSEMBLY PIN, AND DEVICE FOR IMPLEMENTING SUCH A METHOD
WO2006000677A1 (en) * 2004-06-02 2006-01-05 Aktiebolaget Skf Method for controlling tensile stress of a bolt shank such as a screw or dowel pin and device for carrying out said method
CN100458389C (en) * 2004-06-02 2009-02-04 Skf公司 Method for controlling tensile stress of a bolt shank such as a screw or dowel pin and device for carrying out said method
US8201315B2 (en) 2004-06-02 2012-06-19 Aktiebolaget Skf Method for controlling tensile stress of a shank, such as a screw or dowel pin, and device for carrying out said method
WO2008025922A2 (en) * 2006-09-01 2008-03-06 Aktiebolaget Skf Process and device for setting up and controlling a hydraulic chucking of one or a plurality of bolts
FR2905460A1 (en) * 2006-09-01 2008-03-07 Skf Ab METHOD AND DEVICE FOR CONTROLLING HYDRAULIC CLAMPING OF ONE OR MORE BOLTS.
WO2008025922A3 (en) * 2006-09-01 2008-04-17 Skf Ab Process and device for setting up and controlling a hydraulic chucking of one or a plurality of bolts
CN101512313A (en) * 2006-09-01 2009-08-19 Skf公司 Process and device for setting up and controlling a hydraulic chucking of one or a plurality of bolts
US8261421B2 (en) 2006-09-01 2012-09-11 Aktiebolaget Skf Method for setting up and controlling a hydraulic tensioner for applying a preload on one or a plurality of bolts
CN101512313B (en) * 2006-09-01 2013-02-27 Skf公司 Process and device for setting up and controlling a hydraulic chucking of one or a plurality of bolts

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