EP0960340A1 - Accelerometer sensor for detecting knocks and method for making same - Google Patents

Accelerometer sensor for detecting knocks and method for making same

Info

Publication number
EP0960340A1
EP0960340A1 EP98905354A EP98905354A EP0960340A1 EP 0960340 A1 EP0960340 A1 EP 0960340A1 EP 98905354 A EP98905354 A EP 98905354A EP 98905354 A EP98905354 A EP 98905354A EP 0960340 A1 EP0960340 A1 EP 0960340A1
Authority
EP
European Patent Office
Prior art keywords
barrel
bead
washer
base
sensor
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.)
Withdrawn
Application number
EP98905354A
Other languages
German (de)
French (fr)
Inventor
Jean-Christophe Castaing
Patrick Michel Barrabes
Jean-Marc Bruyere
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Continental Automotive France SAS
Original Assignee
Siemens Automotive SA
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Siemens Automotive SA filed Critical Siemens Automotive SA
Publication of EP0960340A1 publication Critical patent/EP0960340A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P1/00—Details of instruments
    • G01P1/02—Housings
    • G01P1/023—Housings for acceleration measuring devices
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L23/00—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid
    • G01L23/22—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines
    • G01L23/221—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines for detecting or indicating knocks in internal combustion engines
    • G01L23/222—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines for detecting or indicating knocks in internal combustion engines using piezoelectric devices
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
    • G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
    • G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
    • G01P15/09—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by piezoelectric pick-up
    • G01P15/0907—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by piezoelectric pick-up of the compression mode type

Definitions

  • the present invention relates to an accelerometric sensor and, more particularly, to such a sensor sensitive to knocking phenomena capable of affecting the operation of an internal combustion engine.
  • a knock sensor known from the prior art, comprising a cylindrical metal base 1 of axis X formed of an axial shaft 2 projecting from an annular shoulder 3, the barrel and the shoulder being both traversed by an axial hole 4, the sensor further comprising a plurality of washers passed over the barrel 2 and stacked on the shoulder 3.
  • a washer 5 made of electrically insulating material
  • a washer 6 made of a piezoelectric material and its electrodes 1 ⁇ , 7 2 each attached to one of its axially spaced end faces
  • a second insulating washer 8 a ground washer 9
  • an elastic washer 10 and a metal nut 11 screwed onto a thread 12 formed on the barrel 2, the nut tightening all of the washers listed above against the shoulder 3 of the em based.
  • the sensor described above can be fixed to an internal combustion engine using a bolt passing through the axial hole 4. It is known that such a sensor is sensitive to forces undergone by the engine along the axis. X, such as vibrations due to the rattling phenomenon, and delivers between the electrodes 7 ⁇ , 7 2 an electrical signal representative of these efforts, the signal resulting from the pressure exerted by the mass 9, accelerated by said efforts, on the washer 6 in piezoelectric material.
  • the computer controlling the operation of the engine reacts by reducing the ignition advance angle in an attempt to eliminate this knock. , which could otherwise be responsible in the long run for mechanical damage to the engine.
  • the use of a nut to hold the various washers of the sensor on the barrel of the base has various drawbacks.
  • the tightening of the nut requires the use of a dynamometric tightening head to establish a predetermined prestress of the piezoelectric washer.
  • the stress thus established may vary with the wear of the head and with variations in the geometries of the thread of the nut or of the thread of the barrel, which may in particular be distorted by impact.
  • metal shavings can form during the machining of the thread and / or the internal thread.
  • a chip 14 thus formed retained in the thread of the barrel or in the thread of the nut, can come off and be inserted between the electrodes 7 ⁇ , 7 2 of the piezoelectric washer 6, thereby establishing a short circuit of these electrodes, which makes the sensor unusable.
  • the object of the present invention is to produce an accelerometric sensor, in particular a knock sensor, which is protected from the short-circuit faults mentioned above, and which has a precise adjustment of the preload applied to the piezoelectric washer, this adjustment being ensured by '' good repeatability in mass production.
  • the present invention also aims to achieve such a sensor which is inexpensive to manufacture.
  • the present invention also aims to provide a method of manufacturing such a sensor.
  • an accelerometric sensor comprising a) a cylindrical base formed by an axial shaft projecting from an annular shoulder, all two crossed by an axial hole, b) a washer made of a piezoelectric material passed over the barrel, c) means for drawing the electric voltage existing between two axially spaced faces of said washer, d) an annular mass also passed over the barrel and e) a stop means cooperating with the annular shoulder to clamp between them said washer and said mass.
  • the stop means consists of a bead projecting radially from said barrel and formed of the material of a predetermined edge thereof, deformed under axial crushing force of said base.
  • this bead does not generate any metal chip capable of establishing a short circuit in the sensor.
  • the position of this bead can be precisely determined, which makes it possible to precisely adjust the preload of the piezoelectric washer.
  • the present invention also provides a method of manufacturing such a sensor, according to which the washer on the base of the base, around its barrel, the washer made of piezoelectric material and the annular mass, this method being remarkable in that 'is applied to the base, between these two ends, an axial crushing force capable of causing the radial expansion of a section of said barrel in the form of a bead for stopping stacked parts.
  • FIG. 1 is a diagram of a knock sensor of the prior art, described in preamble to this description
  • - Figures 2 and 3 illustrate the manufacturing method according to the invention of an embodiment of the sensor according to the invention
  • FIGS. 4 and 5 represent variants of the base of the sensor of FIGS. 2 and 3, and FIGS. 6 and 7 illustrate a variant of the manufacturing process illustrated by FIGS. 2 and 3.
  • FIG. 2 represents the sensor according to the invention, in the stage of its manufacture which immediately precedes the formation of the stop means necessary for the assembly of the various washers stacked on one shoulder 3 of the barrel 1. The latter has then a substantially cylindrical outer surface of revolution.
  • a section 2 : of this barrel is hollowed out internally so as to locally thin the wall of the barrel, which has a minimum thickness in a plane P perpendicular to the axis X, the distance D from this plane P to 1 'shoulder 3 being predetermined and fixed precisely for a purpose explained below.
  • the plane P constitutes a plane of symmetry for the section 2 ⁇ .
  • the various parts 5, 6, ⁇ , 7 2 , 8 and 9 described above are passed around the barrel so that they stack on the shoulder 3 of the base. 1. As shown in FIG. 2, the base being placed on a bearing surface 15, a force F of crushing along the axis X is applied to this base, using a tool 16 , for example.
  • the force F applied is adjusted as a function of the mechanical resistance of the barrel 2, preferably made of a metal capable of creeping locally under this force, and of the thickness of the barrel in the plane P where this thickness is minimal.
  • this minimum thickness defines in this plane a line of weakness of the barrel.
  • this precision can be further improved by using the electric voltage which appears between the electrodes 7 ⁇ , 7 2 during the application of the force F, to control the removal of this force when a voltage level predetermined is reached, this level being representative of that of the prestressing exerted on the piezoelectric washer 6 placed between the shoulder 3 and the bead 17.
  • the formation of the bead 17 does not generate any chip capable of subsequently creating short-circuits between the electrodes 7 ⁇ , 7 2 .
  • the present invention thus greatly reduces the rate of workmanship, which has already been improved by the good repeatability of the prestress adjustment which can be obtained by the means described above.
  • FIG. 4 the section 2 2 has an axial section with a changing profile which eliminates the sharp angles from that of the section 2 in FIG. 1, this changing profile being present both on the inner wall and on the outer wall of the barrel.
  • the section 2 3 has a straight axial profile on the outside wall of the barrel and an evolving profile on the inside wall, in accordance with that of the section 2 2 in FIG. 4.
  • axial lights 18 ⁇ , 18 2 , etc. also distributed circumferentially in section 2 3 . It is understood that each of these lights creates a zone of weakness in the barrel 2 around its central part, zone which allows the collapse of the section 2 3 under axial crushing. It is also understood that the lights 18i can be used alone, in a section of barrel with a wall of constant thickness, or in combination with a wall with an evolving profile as shown in FIG. 5, to create the zone of weakness necessary for the collapse of the section in which they are pierced.
  • the base 1 shown comprises a barrel with a constant thickness wall, having an end edge 2 4 which projects from the top of the stack of parts threaded on this barrel.
  • a stop bead for the stack of parts 5, 6, 7 ⁇ , 7 2 , 8 and 9 is formed by folding this section 2 4 onto this stack, as shown in FIG. 7, using of a punch 19 having at its end an annular groove 19a whose internal diameter is slightly less than that of the axial hole passing through the base 1.
  • the punch 19 penetrates this hole, the edge 24 is pushed back gradually towards the outside of the hole through the groove 19a of the punch, until the material of this slice is spread over the mass 9 in the form of a bead 20 for crimping the pieces threaded on the barrel, between itself and the shoulder 3.
  • this embodiment of the sensor according to the invention is economical due to the simplicity of the geometry of the barrel 2 of the base 1.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Measuring Fluid Pressure (AREA)
  • Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)

Abstract

The invention concerns a sensor comprising a) a cylindrical base (1) formed by an axial shaft (2) projecting from a ring-shaped collar (3), both traversed by an axial bore (4); b) a washer (6) made of piezoelectric material passing on the shaft; c) means for sampling (71, 72) the voltage prevailing between two radial faces of the washer; d) a ring-shaped mass (9) also passing on the shaft (2); and e) stop means co-operating with the ring-shaped collar (3) for mutually squeezing the washer (6) and said mass (9). The stop means consist of a flange (17) projecting from said shaft (2) and formed of the material of a predetermined section thereof, deformed by the crushing stress of said base (1).

Description

Capteur accélérométrique de cliquetis et son procédé de fabrication Accelerometric knock sensor and method of making the same
La présente invention est relative à un capteur accélérométrique et, plus particulièrement, à un tel capteur sensible aux phénomènes de cliquetis susceptible d'affecter le fonctionnement d'un moteur à combustion interne.The present invention relates to an accelerometric sensor and, more particularly, to such a sensor sensitive to knocking phenomena capable of affecting the operation of an internal combustion engine.
On a représenté schématiquement en vue éclatée à la figure 1 du dessin annexé, un capteur de cliquetis connu de la technique antérieure, comprenant une embase métallique cylindrique 1 d'axe X formée d'un fût axial 2 débordant d'un épaulement annulaire 3, le fût et l' épaulement étant tous deux traversés par un trou axial 4, le capteur comprenant en outre une pluralité de rondelles passées sur le fût 2 et empilées sur l' épaulement 3. On trouve ainsi, à partir de cet épaulement et empilés dans cet ordre : une rondelle 5 en matériau électriquement isolant, une rondelle 6 en un matériau piézoélectrique et ses électrodes 1\ , 72 accolées chacune à une de ses faces d'extrémité espacées axialement, une deuxième rondelle isolante 8, une rondelle de masse 9, une rondelle élastique 10 et un écrou métallique 11 vissé sur un filetage 12 formé sur le fût 2, l' écrou serrant l'ensemble des rondelles énumérées ci-dessus contre l' épaulement 3 de l'embase.There is shown schematically in exploded view in FIG. 1 of the appended drawing, a knock sensor known from the prior art, comprising a cylindrical metal base 1 of axis X formed of an axial shaft 2 projecting from an annular shoulder 3, the barrel and the shoulder being both traversed by an axial hole 4, the sensor further comprising a plurality of washers passed over the barrel 2 and stacked on the shoulder 3. Thus there is found, from this shoulder and stacked in this order: a washer 5 made of electrically insulating material, a washer 6 made of a piezoelectric material and its electrodes 1 \ , 7 2 each attached to one of its axially spaced end faces, a second insulating washer 8, a ground washer 9 , an elastic washer 10 and a metal nut 11 screwed onto a thread 12 formed on the barrel 2, the nut tightening all of the washers listed above against the shoulder 3 of the em based.
Le capteur décrit ci-dessus peut être fixé sur un moteur à combustion interne à l'aide d'un boulon passant dans le trou axial 4. On sait qu'un tel capteur est sensible à des efforts subis par le moteur suivant l'axe X, tels que des vibrations dues au phénomène de cliquetis, et délivre entre les électrodes 7η, 72 un signal électrique représentatif de ces efforts, le signal résultant de la pression exercée par la masse 9, accélérée par lesdits efforts, sur la rondelle 6 en matériau piézoélectrique. On sait aussi qu'à la détection d'un cliquetis dans un cylindre d'un moteur à combustion interne, le calculateur commandant le fonctionnement du moteur réagit en réduisant l'angle d'avance à l'allumage pour tenter de faire disparaître ce cliquetis, qui pourrait être autrement responsable, à la longue, d'une dégradation mécanique du moteur.The sensor described above can be fixed to an internal combustion engine using a bolt passing through the axial hole 4. It is known that such a sensor is sensitive to forces undergone by the engine along the axis. X, such as vibrations due to the rattling phenomenon, and delivers between the electrodes 7 η , 7 2 an electrical signal representative of these efforts, the signal resulting from the pressure exerted by the mass 9, accelerated by said efforts, on the washer 6 in piezoelectric material. We also know that upon detection of a knock in a cylinder of an internal combustion engine, the computer controlling the operation of the engine reacts by reducing the ignition advance angle in an attempt to eliminate this knock. , which could otherwise be responsible in the long run for mechanical damage to the engine.
L'utilisation d'un écrou pour maintenir les diverses rondelles du capteur sur le fût de l'embase présente divers inconvénients. D'une part, le serrage de l' écrou impose l'utilisation d'une tête de serrage dynamométrique pour établir une précontrainte prédéterminée de la rondelle piézoélectrique. Dans le cadre d'une fabrication en série d'un tel capteur, la contrainte ainsi établie peut varier avec l'usure de la tête et avec des variations des géométries du taraudage de l' écrou ou du filetage du fût, qui peuvent notamment être faussées par des chocs. D'autre part, des copeaux métalliques peuvent se former pendant l'usinage du filetage et/ou du taraudage. Lors du montage du capteur, un copeau 14 ainsi formé, retenu dans le filetage du fût ou dans le taraudage de l' écrou, peut se détacher et s'insérer entre les électrodes 7ι, 72 de la rondelle piézoélectrique 6, en établissant ainsi un court-circuit de ces électrodes, qui rend le capteur inutilisable.The use of a nut to hold the various washers of the sensor on the barrel of the base has various drawbacks. On the one hand, the tightening of the nut requires the use of a dynamometric tightening head to establish a predetermined prestress of the piezoelectric washer. In the context of mass production of such a sensor, the stress thus established may vary with the wear of the head and with variations in the geometries of the thread of the nut or of the thread of the barrel, which may in particular be distorted by impact. On the other hand, metal shavings can form during the machining of the thread and / or the internal thread. When mounting the sensor, a chip 14 thus formed, retained in the thread of the barrel or in the thread of the nut, can come off and be inserted between the electrodes 7ι, 7 2 of the piezoelectric washer 6, thereby establishing a short circuit of these electrodes, which makes the sensor unusable.
L'utilisation d'un écrou dans un tel capteur présente en outre les inconvénients d'être coûteux et de compliquer l'automatisation de l'assemblage du capteur.The use of a nut in such a sensor also has the disadvantages of being expensive and of complicating the automation of the sensor assembly.
On connaît du brevet allemand n° 195 24 152 un capteur de cliquetis dans lequel les diverses rondelles ne sont pas retenues par un écrou mais par cinq pattes formées par des poinçons attaquant la surface extérieure du fût métallique pour en arracher la matière de ces pattes et la repousser à l'extérieur au-dessus de la rondelle élastique 10, dont la position axiale sur le fût est ainsi fixée.We know from German patent n ° 195 24 152 a knock sensor in which the various washers are not retained by a nut but by five tabs formed by punches attacking the outer surface of the metal barrel to tear the material from these tabs and push it outside above the elastic washer 10, the axial position of the barrel is thus fixed.
Cette solution présente cependant les inconvénients suivants. D'une part, une tel poinçonnage peut être générateur de copeaux métalliques, et donc des courts- circuits évoqués ci-dessus. D'autre part, dans le cadre d'une fabrication en série, la précontrainte de la rondelle piézoélectrique peut varier avec des variations des efforts de poinçonnage, fonction de l'état du tranchant des poinçons, de leur affûtage, etc., etc.However, this solution has the following drawbacks. On the one hand, such punching can generate metal chips, and therefore the short-circuits mentioned above. On the other hand, in the context of mass production, the preload of the piezoelectric washer may vary with variations in the punching forces, depending on the state of the cutting edge of the punches, their sharpening, etc., etc.
La présente invention a pour but de réaliser un capteur accélérométrique, notamment de cliquetis, qui soit protégé des défauts de court-circuit évoqués ci- dessus, et qui présente un réglage précis de la précontrainte appliquée à la rondelle piézoélectrique, ce réglage étant assuré d'une bonne répétitivité dans le cadre d'une fabrication en série.The object of the present invention is to produce an accelerometric sensor, in particular a knock sensor, which is protected from the short-circuit faults mentioned above, and which has a precise adjustment of the preload applied to the piezoelectric washer, this adjustment being ensured by '' good repeatability in mass production.
La présente invention a aussi pour but de réaliser un tel capteur qui soit de fabrication peu coûteuse. La présente invention a encore pour but de fournir un procédé de fabrication d'un tel capteur.The present invention also aims to achieve such a sensor which is inexpensive to manufacture. The present invention also aims to provide a method of manufacturing such a sensor.
On atteint ces buts de l'invention, ainsi que d'autres qui apparaîtront à la lecture de la description qui va suivre, avec un capteur accélérométrique comprenant a) une embase cylindrique formée d'un fût axial débordant d'un épaulement annulaire, tous deux traversés par un trou axial, b) une rondelle en un matériau piézoélectrique passée sur le fût, c) des moyens de prélèvement de la tension électrique existant entre deux faces espacées axialement de ladite rondelle, d) une masse annulaire également passée sur le fût et e) un moyen d'arrêt coopérant avec l' épaulement annulaire pour pincer entre eux ladite rondelle et ladite masse. Suivant l'invention, le moyen d'arrêt est constitué par un bourrelet débordant radialement dudit fût et formé de la matière d'une tranche prédéterminée de celui-ci, déformée sous effort axial d'écrasement de ladite embase.These objects of the invention are achieved, as well as others which will appear on reading the description which follows, with an accelerometric sensor comprising a) a cylindrical base formed by an axial shaft projecting from an annular shoulder, all two crossed by an axial hole, b) a washer made of a piezoelectric material passed over the barrel, c) means for drawing the electric voltage existing between two axially spaced faces of said washer, d) an annular mass also passed over the barrel and e) a stop means cooperating with the annular shoulder to clamp between them said washer and said mass. According to the invention, the stop means consists of a bead projecting radially from said barrel and formed of the material of a predetermined edge thereof, deformed under axial crushing force of said base.
Comme on le verra plus loin, la formation de ce bourrelet n'engendre aucun copeau métallique susceptible d'établir un court-circuit dans le capteur. En outre, la position de ce bourrelet peut être précisément déterminée, ce qui permet de régler avec précision la précontrainte de la rondelle piézoélectrique.As will be seen below, the formation of this bead does not generate any metal chip capable of establishing a short circuit in the sensor. In addition, the position of this bead can be precisely determined, which makes it possible to precisely adjust the preload of the piezoelectric washer.
La présente invention fournit aussi un procédé de fabrication d'un tel capteur, suivant lequel on empile sur l' épaulement de l'embase, autour de son fût, la rondelle en matériau piézoélectrique et la masse annulaire, ce procédé étant remarquable en ce qu'on applique à l'embase, entre ces deux extrémités, un effort axial d'écrasement propre à provoquer l'expansion radiale d'une tranche dudit fût sous la forme d'un bourrelet d'arrêt des pièces empilées.The present invention also provides a method of manufacturing such a sensor, according to which the washer on the base of the base, around its barrel, the washer made of piezoelectric material and the annular mass, this method being remarkable in that 'is applied to the base, between these two ends, an axial crushing force capable of causing the radial expansion of a section of said barrel in the form of a bead for stopping stacked parts.
D'autres caractéristiques et avantages de la présente invention apparaîtront à la lecture de la description qui va suivre et à l'examen du dessin annexé dans lequel : la figure 1 est un schéma d'un capteur de cliquetis de la technique antérieure, décrit en préambule de la présente description, - les figures 2 et 3 illustrent le procédé de fabrication suivant l'invention d'un mode de réalisation du capteur suivant l'invention,Other characteristics and advantages of the present invention will appear on reading the description which follows and on examining the appended drawing in which: FIG. 1 is a diagram of a knock sensor of the prior art, described in preamble to this description, - Figures 2 and 3 illustrate the manufacturing method according to the invention of an embodiment of the sensor according to the invention,
- les figures 4 et 5 représentent des variantes de l'embase du capteur des figures 2 et 3, et - les figures 6 et 7 illustrent une variante du procédé de fabrication illustré par les figures 2 et 3.FIGS. 4 and 5 represent variants of the base of the sensor of FIGS. 2 and 3, and FIGS. 6 and 7 illustrate a variant of the manufacturing process illustrated by FIGS. 2 and 3.
On se réfère à la figure 2 du dessin annexé où l'on a représenté l'ensemble des pièces d'un mode de réalisation du capteur suivant l'invention, avant la formation du bourrelet constituant le moyen d'arrêt évoqué ci-dessus. Sur cette figure et les suivantes, des références numériques identiques à celles utilisées sur la figure 1 représentent des organes ou éléments identiques ou analogues. C'est ainsi qu'on retrouve sur la figure 2 l'embase 1, son fût 2 et son épaulement 3, les rondelles isolantes 5 et 8, la rondelle piézoélectrique 6 et ses électrodes ι i, et la masse 9. On remarquera l'absence de la rondelle élastique 10, bien que la présence de celle-ci soit optionnelle, comme on le verra plus loin.Referring to Figure 2 of the accompanying drawing where there is shown all the parts of an embodiment of the sensor according to the invention, before the formation of the bead constituting the stop means mentioned above. In this figure and the following ones, reference numerals identical to those used in FIG. 1 represent identical or analogous members or elements. Thus we find in Figure 2 the base 1, its barrel 2 and its shoulder 3, the insulating washers 5 and 8, the piezoelectric washer 6 and its electrodes ι i, and the mass 9. Note l absence of the elastic washer 10, although the presence of the latter is optional, as will be seen below.
La figure 2 représente le capteur suivant l'invention, dans l'étape de sa fabrication qui précède immédiatement la formation du moyen d'arrêt nécessaire à l'assemblage des diverses rondelles empilées sur 1' épaulement 3 du fût 1. Celui-ci présente alors une surface extérieure sensiblement cylindrique de révolution.FIG. 2 represents the sensor according to the invention, in the stage of its manufacture which immediately precedes the formation of the stop means necessary for the assembly of the various washers stacked on one shoulder 3 of the barrel 1. The latter has then a substantially cylindrical outer surface of revolution.
Suivant la présente invention, une tranche 2: de ce fût est évidée intérieurement de manière à amincir localement la paroi du fût, qui présente une épaisseur minimale dans un plan P perpendiculaire à l'axe X, la distance D de ce plan P à 1 ' épaulement 3 étant prédéterminée et fixée avec précision pour un but expliqué ci-dessous. De préférence, le plan P constitue un plan de symétrie pour la tranche 2ι. Pour fabriquer le capteur suivant l'invention, on passe autour du fût les diverses pièces 5, 6, ι, 72, 8 et 9 décrites ci-dessus de manière qu'elles s'empilent sur 1' épaulement 3 de l'embase 1. Comme représenté à la figure 2, l'embase étant posée sur une surface d'appui 15, on applique à cette embase un effort F d'écrasement suivant l'axe X, à l'aide d'un outil 16 de bouterolleuse, par exemple.According to the present invention, a section 2 : of this barrel is hollowed out internally so as to locally thin the wall of the barrel, which has a minimum thickness in a plane P perpendicular to the axis X, the distance D from this plane P to 1 'shoulder 3 being predetermined and fixed precisely for a purpose explained below. Preferably, the plane P constitutes a plane of symmetry for the section 2ι. To manufacture the sensor according to the invention, the various parts 5, 6, ι, 7 2 , 8 and 9 described above are passed around the barrel so that they stack on the shoulder 3 of the base. 1. As shown in FIG. 2, the base being placed on a bearing surface 15, a force F of crushing along the axis X is applied to this base, using a tool 16 , for example.
L'effort F appliqué est ajusté en fonction de la résistance mécanique du fût 2, réalisé de préférence en un métal susceptible de fluer localement sous cet effort, et de l'épaisseur du fût dans le plan P où cette épaisseur est minimale.The force F applied is adjusted as a function of the mechanical resistance of the barrel 2, preferably made of a metal capable of creeping locally under this force, and of the thickness of the barrel in the plane P where this thickness is minimal.
En effet, cette épaisseur minimale définit dans ce plan une ligne de faiblesse du fût. En ajustant l'effort F appliqué pour que la limite élastique du métal du fût soit dépassée au moins au niveau du plan P, et seulement dans la tranche 2ι du fût, on est assuré que celle-ci s'effondre sous l'effort appliqué. Cet effondrement provoque une expansion radiale de la matière de la tranche, sous la forme du bourrelet 17 représenté à la figure 3 qui schématise la géométrie du capteur terminé.Indeed, this minimum thickness defines in this plane a line of weakness of the barrel. By adjusting the force F applied so that the elastic limit of the metal of the barrel is exceeded at least at the plane P, and only in the section 2ι of the barrel, it is ensured that the latter collapses under the force applied . This collapse causes a radial expansion of the material of the wafer, in the form of the bead 17 shown in Figure 3 which shows schematically the geometry of the finished sensor.
Il apparaît sur la figure 3 que des parties de la tranche 2ι du fût, situées de part et d'autre du plan P de la ligne de faiblesse, viennent en butée l'une contre l'autre dans un plan P' sensiblement perpendiculaire à l'axe X. En ajustant convenablement le module de l'effort F et le temps d'application de cet effort, on comprend que la position de ce plan P' peut être réglée avec précision, la mise en butée précitée, combinée avec l'appui du bourrelet 17 sur la masse 9, accroissant brusquement la résistance du fût qui s'oppose alors à tout fléchissement supplémentaire. La précontrainte de la rondelle piézoélectrique passée avec les autres pièces sur le fût 2, entre l' épaulement 3 et le bourrelet 17, est alors réglée avec précision.. It appears in Figure 3 that parts of the section 2ι of the barrel, located on either side of the plane P of the line of weakness, abut one against the other in a plane P 'substantially perpendicular to the axis X. By suitably adjusting the modulus of the force F and the time of application of this force, it is understood that the position of this plane P 'can be adjusted with precision, the abovementioned abutment, combined with the 'support of the bead 17 on the mass 9, suddenly increasing the resistance of the barrel which then opposes any further bending. The prestressing of the piezoelectric washer passed with the other parts on the barrel 2, between the shoulder 3 and the bead 17, is then adjusted with precision. .
A cet égard, on remarquera qu'on pourra améliorer encore cette précision en utilisant la tension électrique qui apparaît entre les électrodes 7ι, 72 pendant l'application de l'effort F, pour commander la suppression de cet effort quand un niveau de tension prédéterminée est atteint, ce niveau étant représentatif de celui de la précontrainte exercée sur la rondelle piézoélectrique 6 placée entre l' épaulement 3 et le bourrelet 17. On remarquera en outre que la formation du bourrelet 17 n'est génératrice d'aucun copeau susceptible de créer ultérieurement des courts-circuits entre les électrodes 7ι, 72. Dans le cadre d'une fabrication en série, la présente invention diminue ainsi fortement le taux de malfaçon, déjà amélioré par la bonne répétitivité du réglage de la précontrainte que l'on peut obtenir par les moyens décrits ci-dessus.In this regard, it will be noted that this precision can be further improved by using the electric voltage which appears between the electrodes 7ι, 7 2 during the application of the force F, to control the removal of this force when a voltage level predetermined is reached, this level being representative of that of the prestressing exerted on the piezoelectric washer 6 placed between the shoulder 3 and the bead 17. It will also be noted that the formation of the bead 17 does not generate any chip capable of subsequently creating short-circuits between the electrodes 7ι, 7 2 . In the context of mass production, the present invention thus greatly reduces the rate of workmanship, which has already been improved by the good repeatability of the prestress adjustment which can be obtained by the means described above.
On a représenté aux figures 4 et 5 des variantes possibles de la forme de la tranche 2j du fût de l'embase, propres à permettre la formation d'un bourrelet sous écrasement axial de cette embase. A la figure 4, la tranche 22 présente une section axiale à profil évolutif qui supprime les angles vifs de celle de la tranche 2ι de la figure 1, ce profil évolutif étant présent aussi bien sur la paroi intérieure que sur la paroi extérieure du fût. A la figure 5, la tranche 23 présente un profil axial droit sur la paroi extérieure du fût et un profil évolutif sur la paroi intérieure, conforme à celui de la tranche 22 de la figure 4.There are shown in Figures 4 and 5 possible variants of the shape of the edge 2j of the barrel of the base, suitable for allowing the formation of a bead under axial crushing of this base. In FIG. 4, the section 2 2 has an axial section with a changing profile which eliminates the sharp angles from that of the section 2 in FIG. 1, this changing profile being present both on the inner wall and on the outer wall of the barrel. . In FIG. 5, the section 2 3 has a straight axial profile on the outside wall of the barrel and an evolving profile on the inside wall, in accordance with that of the section 2 2 in FIG. 4.
On a représenté en outre, à la figure 5, des lumières axiales 18ι, 182, etc. également distribuées circonférentiellement dans la tranche 23. On comprend que chacune de ces lumières crée une zone de faiblesse dans le fût 2 autour de sa partie centrale, zone qui permet l'effondrement de la tranche 23 sous écrasement axial. On comprend aussi que les lumières 18i peuvent être utilisées seules, dans une tranche de fût à paroi d'épaisseur constante, ou en combinaison avec une paroi à profil évolutif comme représenté à la figure 5, pour créer la zone de faiblesse nécessaire à l'effondrement de la tranche dans laquelle elles sont percées.There is also shown, in Figure 5, axial lights 18ι, 18 2 , etc. also distributed circumferentially in section 2 3 . It is understood that each of these lights creates a zone of weakness in the barrel 2 around its central part, zone which allows the collapse of the section 2 3 under axial crushing. It is also understood that the lights 18i can be used alone, in a section of barrel with a wall of constant thickness, or in combination with a wall with an evolving profile as shown in FIG. 5, to create the zone of weakness necessary for the collapse of the section in which they are pierced.
Il est clair que les bourrelets créés à l'aide des fûts conformes à ceux représentés aux figures 2 et 4 ont une forme annulaire continue alors que celui créé avec le fût de la figure 5 est discontinu, du fait de la présence des lumières.It is clear that the beads created using the drums conforming to those shown in Figures 2 and 4 have a continuous annular shape while that created with the barrel of Figure 5 is discontinuous, due to the presence of lights.
A la figure 6, l'embase 1 représentée comprend un fût à paroi d'épaisseur constante, présentant une tranche d'extrémité 24 qui déborde du sommet de la pile des pièces enfilées sur ce fût.In Figure 6, the base 1 shown comprises a barrel with a constant thickness wall, having an end edge 2 4 which projects from the top of the stack of parts threaded on this barrel.
Suivant l'invention, on constitue un bourrelet d'arrêt de la pile des pièces 5, 6, 7ι,72, 8 et 9 en rabattant cette tranche 24 sur cette pile, comme représenté à la figure 7, à l'aide d'un poinçon 19 présentant à son extrémité une gorge annulaire 19a dont le diamètre intérieur est légèrement inférieur à celui du trou axial traversant l'embase 1. Lors de la pénétration du poinçon 19 dans ce trou, la tranche 24 est refoulée progressivement vers l'extérieur du trou par la gorge 19a du poinçon, jusqu'à l'étalement de la matière de cette tranche sur la masse 9 sous la forme d'un bourrelet 20 de sertissage des pièces enfilées sur le fût, entre lui-même et l' épaulement 3. On remarquera que ce mode de réalisation du capteur suivant l'invention est économique du fait de la simplicité de la géométrie du fût 2 de l'embase 1.According to the invention, a stop bead for the stack of parts 5, 6, 7ι, 7 2 , 8 and 9 is formed by folding this section 2 4 onto this stack, as shown in FIG. 7, using of a punch 19 having at its end an annular groove 19a whose internal diameter is slightly less than that of the axial hole passing through the base 1. When the punch 19 penetrates this hole, the edge 24 is pushed back gradually towards the outside of the hole through the groove 19a of the punch, until the material of this slice is spread over the mass 9 in the form of a bead 20 for crimping the pieces threaded on the barrel, between itself and the shoulder 3. It will be noted that this embodiment of the sensor according to the invention is economical due to the simplicity of the geometry of the barrel 2 of the base 1.
Bien entendu l'invention n'est pas limitée aux modes de réalisation décrits et représentés qui n'ont été donnés qu'à titre d'exemples. C'est ainsi que les capteurs des figures 3 et 7 pourraient être équipés d'une rondelle élastique telle que la rondelle 10 du capteur de la figure 1, sans que l'on sorte du cadre de l'invention. On remarquera cependant que la précision des moyens de réglage de la précontrainte de la rondelle piézoélectrique proposés par la présente invention permet de se passer éventuellement de cette rondelle. Of course, the invention is not limited to the embodiments described and shown which have been given only by way of examples. Thus the sensors of Figures 3 and 7 could be equipped with an elastic washer such as the washer 10 of the sensor of Figure 1, without departing from the scope of the invention. It will however be noted that the precision of the means for adjusting the preload of the piezoelectric washer proposed by the present invention makes it possible to dispense with this washer if necessary.

Claims

REVENDICATIONS
1. Capteur accélérométrique comprenant a) une embase cylindrique (1) formée d'un fût axial (2) débordant d'un épaulement annulaire (3), tous deux traversés par un trou axial (4), b) une rondelle (6) en un matériau piézoélectrique passée sur le fût, c) des moyens de prélèvement (7ι,72) de la tension électrique existant entre deux faces radiales de ladite rondelle, d) une masse annulaire (9) également passée sur le fût (2) et e) un moyen d'arrêt coopérant avec l' épaulement annulaire1. Accelerometric sensor comprising a) a cylindrical base (1) formed by an axial shaft (2) projecting from an annular shoulder (3), both crossed by an axial hole (4), b) a washer (6) made of a piezoelectric material passed over the barrel, c) means for taking (7ι, 7 2 ) the electric voltage existing between two radial faces of said washer, d) an annular mass (9) also passed over the barrel (2) and e) a stop means cooperating with the annular shoulder.
(3) pour pincer entre eux ladite rondelle (6) et ladite masse (9), caractérisé en ce que ledit moyen d'arrêt est constitué par un bourrelet (17,-20) débordant radialement dudit fût (2) et formé de la matière d'une tranche ( 2 ) prédéterminée de celui-ci, déformée sous effort axial d'écrasement de ladite embase (1).(3) for pinching together said washer (6) and said mass (9), characterized in that said stop means is constituted by a bead (17, -20) projecting radially from said barrel (2) and formed of material of a predetermined slice (2) thereof, deformed under axial crushing force of said base (1).
2. Capteur conforme à la revendication 1, caractérisé en ce que le bourrelet (17) est formé dans une tranche (2ι;22;23) à paroi amincie du fût (2). 2. Sensor according to claim 1, characterized in that the bead (17) is formed in a wafer (2ι; 2 2 ; 2 3 ) with thinned wall of the barrel (2).
3. Capteur conforme à l'une quelconque des revendications 1 et 2, caractérisé en ce que le bourrelet est formé dans une tranche (2 ) du fût percée de lumières (18ι) .3. Sensor according to any one of claims 1 and 2, characterized in that the bead is formed in a slice (2) of the barrel pierced with lights (18ι).
4. Capteur conforme à la revendication 1, caractérisé en ce que la paroi du fût (2) de l'embase (1) est d'épaisseur sensiblement constante et en ce que la tranche (24) dudit fût qui constitue ledit bourrelet (20) est située à l'extrémité du fût opposée à celle qui est solidaire dudit épaulement annulaire (3), ladite rondelle (6) en matériau piézoélectrique et ladite masse (9) étant serties ensemble entre ledit bourrelet (20) et ledit épaulement (3) .4. Sensor according to claim 1, characterized in that the wall of the barrel (2) of the base (1) is of substantially constant thickness and in that the edge (2 4 ) of said barrel which constitutes said bead ( 20) is located at the end of the barrel opposite to that which is integral with said annular shoulder (3), said washer (6) made of piezoelectric material and said mass (9) being crimped together between said bead (20) and said shoulder ( 3).
5. Capteur conforme à l'une quelconque des revendications 1, 2 et 4, caractérisé en ce que ledit bourrelet (17; 20) présente une forme annulaire continue. 5. Sensor according to any one of claims 1, 2 and 4, characterized in that said bead (17; 20) has a continuous annular shape.
6. Capteur conforme à la revendication 3, caractérisé en ce que ledit bourrelet présente une forme annulaire discontinue.6. Sensor according to claim 3, characterized in that said bead has a discontinuous annular shape.
7. Procédé de fabrication du capteur conforme à la revendication 1, suivant lequel on empile sur l' épaulement (3) de l'embase (1), autour de son fût (2), la rondelle en matériau piézoélectrique et la masse annulaire (9), caractérisé en ce qu'on applique à l'embase, entre ses deux extrémités, un effort axial d'écrasement propre à provoquer l'expansion radiale d'une tranche (2±) dudit fût sous la forme d'un bourrelet (17;20) d'arrêt des pièces empilées.7. A method of manufacturing the sensor according to claim 1, according to which is stacked on the shoulder (3) of the base (1), around its barrel (2), the washer made of piezoelectric material and the annular mass ( 9), characterized in that an axial crushing force applied to the base, between its two ends, capable of causing the radial expansion of a section (2 ± ) of said barrel in the form of a bead (17; 20) for stopping the stacked parts.
8. Procédé conforme à la revendication 7, caractérisé en ce qu'on utilise un fût présentant une zone de faiblesse de position axiale prédéterminée dans ladite tranche (2ι) .8. Method according to claim 7, characterized in that a barrel is used having a zone of weakness of predetermined axial position in said section (2ι).
9. Procédé conforme à la revendication 8, caractérisé en ce qu'on utilise une embase (1) dont le fût (2) est aminci dans ladite tranche (2ι;22;23).9. A method according to claim 8, characterized in that a base (1) is used whose barrel (2) is thinned in said wafer (2ι; 2 2 ; 2 3 ).
10. Procédé conforme à la revendication 8 ou 9, caractérisé en ce qu'on utilise une embase (1) dont le fût10. A method according to claim 8 or 9, characterized in that one uses a base (1) whose barrel
(2) est percé de lumières (18 dans ladite tranche (23) .(2) is pierced with lights (18 in said section (2 3 ).
11. Procédé conforme à l'une quelconque des revendications 7 à 10, caractérisé en ce qu'on applique ledit effort axial avec une bouterolleuse. 11. Method according to any one of claims 7 to 10, characterized in that the said axial force is applied with a dieser.
12. Procédé conforme à . l'une quelconque des revendications 7 à 10, caractérisé en ce qu'on applique ledit effort axial avec un poinçon (19) profilé pour rabattre ladite tranche (24) du fût sur ladite pile de pièces. 12. Process according to. any one of claims 7 to 10, characterized in that the said axial force is applied with a punch (19) profiled to fold the said edge (2 4 ) of the barrel onto the said stack of parts.
13. Procédé conforme à l'une quelconque des revendications 7 à 12, caractérisé en ce qu'on supprime l'application de l'effort axial sous la commande du signal de tension électrique émis par le capteur pendant ladite application. 13. Method according to any one of claims 7 to 12, characterized in that it eliminates the application of the axial force under the control of the electrical voltage signal emitted by the sensor during said application.
EP98905354A 1997-02-13 1998-01-26 Accelerometer sensor for detecting knocks and method for making same Withdrawn EP0960340A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR9701677 1997-02-13
FR9701677A FR2759458B1 (en) 1997-02-13 1997-02-13 ACCELEROMETRIC CLICK SENSOR AND MANUFACTURING METHOD THEREOF
PCT/EP1998/000424 WO1998036280A1 (en) 1997-02-13 1998-01-26 Accelerometer sensor for detecting knocks and method for making same

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EP0960340A1 true EP0960340A1 (en) 1999-12-01

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EP (1) EP0960340A1 (en)
JP (1) JP3222146B2 (en)
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Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20000010532A (en) * 1996-04-19 2000-02-15 모리시타 요이찌 Method and apparatus for manufacture of laminated optical disc
DE10044476A1 (en) * 2000-09-08 2002-04-04 Bosch Gmbh Robert Vibration sensor for direct or indirect attachment to a component having vibrations
JP2005227265A (en) * 2004-01-15 2005-08-25 Ngk Spark Plug Co Ltd Knocking sensor
JP4121092B2 (en) * 2005-11-22 2008-07-16 三菱電機株式会社 Knock sensor
JP4162012B2 (en) * 2006-03-30 2008-10-08 三菱電機株式会社 Knock sensor
JP2013007612A (en) * 2011-06-23 2013-01-10 Ngk Spark Plug Co Ltd Non-resonance type knocking sensor
JP5876448B2 (en) 2012-09-20 2016-03-02 日本特殊陶業株式会社 Knocking sensor
JP6175149B2 (en) * 2012-09-20 2017-08-02 日本特殊陶業株式会社 Manufacturing method of knocking sensor
CN107505089B (en) * 2016-06-14 2021-01-12 日本特殊陶业株式会社 Method for manufacturing knock sensor
WO2018068097A1 (en) 2016-10-13 2018-04-19 South East Water Corporation Water meter and systems and networks comprising the same

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RO78375A2 (en) * 1981-01-20 1983-08-03 Institutul De Cercetare Stiintifica Si Inginerie Tehnologica Pentru Industria Electrotehnice,Ro TRADUCTOR PIEZOLECTRIC
FR2548376B1 (en) * 1983-07-01 1986-02-28 Cartier Jean ACCELEROMETRIC DEVICE
DE4123786A1 (en) * 1991-07-18 1993-01-21 Bosch Gmbh Robert KNOCK SENSOR
FR2703772B1 (en) * 1993-04-10 1995-05-19 Bosch Gmbh Robert Pressure socket, in particular for a knock sensor.
DE19524152C1 (en) * 1995-07-03 1996-05-23 Bosch Gmbh Robert Vibration pick=up e.g. for IC engine knock sensor

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9836280A1 *

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FR2759458A1 (en) 1998-08-14
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US6212940B1 (en) 2001-04-10
JP3222146B2 (en) 2001-10-22
WO1998036280A1 (en) 1998-08-20

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