EP0005407A1 - End of stroke decelerating and/or accelerating means for rectilinear, alternating moving parts - Google Patents

End of stroke decelerating and/or accelerating means for rectilinear, alternating moving parts Download PDF

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Publication number
EP0005407A1
EP0005407A1 EP79400286A EP79400286A EP0005407A1 EP 0005407 A1 EP0005407 A1 EP 0005407A1 EP 79400286 A EP79400286 A EP 79400286A EP 79400286 A EP79400286 A EP 79400286A EP 0005407 A1 EP0005407 A1 EP 0005407A1
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EP
European Patent Office
Prior art keywords
piston
cylinder
aforementioned
fluid flow
section
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.)
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Application number
EP79400286A
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German (de)
French (fr)
Inventor
André Raveneau
Roland Martinet
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Climax France SA
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Climax France SA
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Publication of EP0005407A1 publication Critical patent/EP0005407A1/en
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F15B15/22—Other details, e.g. assembly with regulating devices for accelerating or decelerating the stroke
    • F15B15/223—Other details, e.g. assembly with regulating devices for accelerating or decelerating the stroke having a piston with a piston extension or piston recess which completely seals the main fluid outlet as the piston approaches its end position
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F15B15/22—Other details, e.g. assembly with regulating devices for accelerating or decelerating the stroke
    • F15B15/222—Other details, e.g. assembly with regulating devices for accelerating or decelerating the stroke having a piston with a piston extension or piston recess which throttles the main fluid outlet as the piston approaches its end position

Definitions

  • the invention generally relates to a device for controlling the deceleration and / or acceleration of a movable element in a rectilinear back and forth movement, in the vicinity of at least one of the end of travel dead center points.
  • the element controlled for example, by a pressurized fluid, and relates more particularly to the control of the speed at the end and / or at the start of the stroke of a piston of a cylinder, in particular with double effect.
  • a cylinder is equipped, in principle, with at least one such device often called “damping system or damper" which is operational only in the vicinity of the neutral point of the piston with which it is associated. Only one damping system is necessary in the case of a single-acting cylinder, while two damping systems are necessary in the case of a double-acting cylinder. Such a damping system is intended to suppress the shocks of the piston with the associated bottom of the cylinder body, which allows good resistance of the cylinder in endurance and relatively silent operation.
  • the object of the invention is to eliminate this drawback, by ensuring not a pure and simple switching between a main flow path and a secondary flow path of smaller section, for the fluid discharged by the piston, but a switching progressive between these two flow paths in order to eliminate any oscillatory phenomenon which could accompany the deceleration and / or acceleration of the piston.
  • the invention provides a device for controlling the deceleration and / or acceleration of a mobile element in a reciprocating rectilinear reciprocating movement, in the vicinity of at least one of the dead centers of end of travel of said movable element controlled, for example, by a pressurized fluid, comprising two coaxially aligned pistons of different diameter cooperating respectively, in a sealed manner in the vicinity of the dead center considered, with two coaxially aligned cylinders of different diameter, one of the cylinders being connected to a main fluid flow path, the other cylinder being connected to a calibrated secondary fluid flow path of smaller cross-section than the section of the main fluid flow path, characterized in that the cylinder connected to the main fluid flow path is closed, in a sealed manner, progressively by the associated piston as said moving element approaches the associated dead center of its course.
  • the piston associated with the cylinder of smaller diameter is machined so that its cross section increases as it enters its associated cylinder.
  • the aforementioned machining consists in carrying out a release of material in the aforementioned piston, such as for example a flat inclined with respect to the direction of the movable element.
  • the aforementioned machining is carried out at the bore of smaller section, so that the cross section of this bore decreases as the piston associated enters this bore.
  • the cylinder for example pneumatic and double-acting to which the invention applies, consists of a hollow body 2 or cylinder in which a piston 3 can slide axially, the outer peripheral surface of which is in tight sliding contact, by means of an annular lining 4 preferably of the lip type forming a seal carried by the piston 3, with the cylinder 2.
  • the cylinder 2 of the jack is closed at its two free ends by two blocks 5, 6 respectively.
  • the end block 5 or bottom of the jack 1 is crossed by a central blind bore 7 axially aligned with the axis of the piston 3.
  • This bore 7 communicates towards its blind end with a transverse channel 8 which communicates itself to its other end either with the atmosphere or with a source of pressurized fluid (not shown).
  • This channel 8 acts as the main flow path for the fluid which is discharged by the piston 3.
  • a blind channel 9 is machined in said bottom, parallel to the axis of the bore 7.
  • the end of this channel 9 communicates with a channel transverse 10 opening on the one hand towards the outside and on the other hand into the bore 7.
  • an adjusting screw 11 is mounted in this channel 10 for regulating the flow of fluid passing through the channel 9 and going towards the bore 7.
  • This channel 9 and the part of channel 10 located between channel 9 and bore 7, constitute a secondary flow path for the fluid discharged by the piston 3. It is important to note that the section of the channel 9 is significantly less than the section of the channel 8 which communicates either with the atmosphere or with a source of pressurized fluid.
  • a discharge valve system 12 adjustable or not, known per se, which regulates the flow rate of the fluid flow between the cylinder 2 and the outside via two channels 13, 14 respectively parallel and perpendicular to the axis of the cylinder.
  • the other end block 6 or cylinder base 1 is constituted in a manner substantially identical to the end block 5. The only difference is that it has a second bore 15 in the extension of the bore 7 associated to allow the rod 16 of the piston 3 to protrude outside the jack 1.
  • bosses 17a, 17b On either side of the piston 3 are provided respectively two bosses 17a, 17b axially aligned with the axis of the cylinder 1 and which have a cross section very slightly less than the section of the bores 7 into which they are intended to penetrate. It should be noted that the boss 17b of the piston 3 is extended by rod 16 of the piston. Since these bosses 17a, 17b are intended to cooperate in leaktight fashion with the associated bores 7, an annular lining 18 forming a seal is provided at each bore 7. This packing 18 is for example mounted in the vicinity of the open end of the associated bore 7.
  • At least one material clearance 19 such as the cross section is provided at each boss 17a, 17b. of each boss increases as the latter enters its associated bore 7.
  • This clearance 19 may be a flat inclined along the axis of the piston, a countersink or a groove of square section, rounded, flat, vee, and progressive in a continuous or progressive manner in successive stages over all or part of the length. of the corresponding boss.
  • the piston 3 When the piston 3 is between its two neutral points and substantially beyond them, the piston 3 has a substantially constant speed and, according to its direction of movement, the fluid which it discharges is directed towards the atmosphere, in the case of a pneumatic cylinder, passing through the corresponding bore 7 which is not closed and the associated channel 8 forming the main escape route.
  • the piston 3 arrives in the vicinity of its neutral point located on the side of the bottom 5 of the jack 1, and when the end of the boss 17a arrives close to the entry of the associated bore 7, the passageway for the pumped fluid by the piston 3 in the direction of the discharge channel 8 is only partially closed, that is to say that only part of the seal 18 cooperates with the outer peripheral surface of the boss 17a.
  • the boss 17a penetrates further forward inside the associated bore 7 by progressively sealing this bore thanks to the seal annular 18 and this, thanks to the release of material 19 provided at the boss 17a. Consequently, the main escape route (chamber 20, channel 8) is not closed instantly but gradually. Under these conditions, the pressure then increases slowly and gradually in the chamber 21 forming the damping chamber, which causes a weak and continuous deceleration of the piston 3.
  • the bore 7 is completely closed by the boss 17a, that is to say that the seal 18 cooperates through its entire surface with the peripheral surface of the boss 17a.
  • the volume of the damping chamber 21 has considerably decreased, and the little fluid which it still contains escapes towards the atmosphere by flowing through the longitudinal channel 9, the transverse channel 10, the bore and the exhaust channel 8.
  • the flow rate of this fluid can be easily adjusted by means of the adjusting screw 11.
  • the piston 3 is therefore always subjected to a deceleration which gradually decreases, which enables it to reach its neutral at practically zero speed without causing any mechanical shock.
  • the channel 8 of the end block 5 now constitutes a channel for supplying pressurized fluid
  • the channel 8 associated with the other block d end 6 of cylinder 2 will communicate with the atmosphere.
  • the clearance 19 provided on the boss 17a makes it possible to gradually admit the pressurized fluid into the damping chamber 21, which thus avoids a sudden change in flow when the boss 17a will be out of its bore 7.
  • continuous progressive acceleration is ensured, without untimely deceleration, during this phase of racing before the next phase where the piston 3 moves at a practically constant speed.
  • the piston 3 will be decelerated by the cooperation of its boss 17b with the associated bore 7 and this, in a manner identical to that which has been described previously.
  • auxiliary relief valve system 12 The role of the auxiliary relief valve system 12 is to make it possible to weaken the deceleration of the piston 3 by limiting the rise in pressure in the damping chamber, that is to say that its action is added to that produced by the clearances 19 provided either on the bosses of the piston or in the bores with which these bosses cooperate.
  • release of material 19 such as a countersink or groove can be produced both on a generator of the boss (or of the associated bore), parallel to the axis of the piston, and on a generator s '' winding in a helix according to a regular pitch or not.
  • the only imperative for clearance 19 is to ensure progressive closure of the associated bore.
  • Such a control device applies equally well to a single-acting cylinder, and is not limited to pneumatic cylinders but to any cylinder controlled to move by any fluid, and in particular to hydraulic cylinders.

Abstract

The piston (3) of the actuator (1) possesses at least one projection (17a) aligned coaxially with the piston and intended to penetrate leaktightly into a blind hole (20) provided in the associated base (5) of the actuator (1) and connected to the atmosphere. This projection (17a) possesses at least one material relief (19) such that the cross-section of the projection increases gradually as it penetrates into the bore (20). The main escape path of the fluid discharged by the piston (3) is thus blocked gradually and not instantaneously. The invention applies, in particular, to pneumatic actuators. <IMAGE>

Description

L'invention concerne généralement un dispositif de contrôle de la décélération et/ou de l'accélération d'un élément mobile suivant un mouvement rectiligne de va-et-vient, au voisinage d'au moins un des points morts de fin de course de l'élément commandé, par exemple, par un fluide sous pression, et se rapporte plus particulièrement au contrôle de la vitesse en fin et/ou au début de course d'un piston d'un vérin notamment à double effet.The invention generally relates to a device for controlling the deceleration and / or acceleration of a movable element in a rectilinear back and forth movement, in the vicinity of at least one of the end of travel dead center points. the element controlled, for example, by a pressurized fluid, and relates more particularly to the control of the speed at the end and / or at the start of the stroke of a piston of a cylinder, in particular with double effect.

De façon générale, un vérin est équipé, en principe, d'au moins un tel dispositif souvent dénommé "système d'amortissement ou amortisseur" qui n'est opératif qu'au voisinage du point mort du piston auquel il est associé. Un seul système d'amortissement est nécessaire dans le cas d'un vérin à simple effet, alors que deux systèmes d'amortissement sont nécessaires dans le cas d'un vérin à double effet. Un tel système amortisseur est destiné à supprimer les chocs du piston avec le fond associé du corps du vérin, ce qui permet une bonne tenue du vérin en endurance et un fonctionnement relativement silencieux.In general, a cylinder is equipped, in principle, with at least one such device often called "damping system or damper" which is operational only in the vicinity of the neutral point of the piston with which it is associated. Only one damping system is necessary in the case of a single-acting cylinder, while two damping systems are necessary in the case of a double-acting cylinder. Such a damping system is intended to suppress the shocks of the piston with the associated bottom of the cylinder body, which allows good resistance of the cylinder in endurance and relatively silent operation.

Au voisinage d'un point mort de la course du piston, l'amortissement se réalise par une diminution importante et quasiment instantanée de la section de passage de la voie d'écoulement du fluide refoulé par le piston. Autrement dit, on passe d'une première section de passage à une seconde section de passage par simple commutation.In the vicinity of a dead center of the piston stroke, the damping is achieved by a significant and almost instantaneous reduction in the cross section of the flow path of the fluid discharged by the piston. In other words, we pass from a first passage section to a second passage section by simple switching.

Cette commutation, du fait de la réduction importante de la section de passage de l'écoulement du fluide refoulé par le piston, provoque un décélération très rapide entraînant un choc au niveau du piston, choc qui provoque un phénomène oscillatoire perturbateur tendant à limiter les performances des vérins. Par conséquent, un tel inconvénient ne permet pas notamment d'utiliser ces vérins lorsque, dans certaines applications, il est nécessaire d'avoir des déplacements au cours desquels tout choc est à exclure.This switching, due to the significant reduction in the cross-section of the flow of the fluid discharged by the piston, causes a very rapid deceleration causing a shock at the level of the piston, shock which causes a disturbing oscillatory phenomenon tending to limit performance. cylinders. Consequently, such a drawback does not make it possible in particular to use these jacks when, in certain applications, it is necessary to have displacements during which any shock is to be excluded.

Lors de l'inversion du mouvement du piston du vérin, le même phénomène oscillatoire (accélérations et décélérations successives) se produit lorsque le système d'amortissement n'a plus aucune influence, c'est-à-dire lorsque le piston se trouve sensiblement au-delà du point mort de sa course auquel le système d'amortissement est associé.During the reversal of the piston piston movement, the same oscillatory phenomenon (successive accelerations and decelerations) occurs when the damping system no longer has any influence, that is to say when the piston is substantially beyond the neutral point of its travel with which the damping system is associated.

L'invention a pour but de supprimer cet inconvénient, en assurant non pas une commutation pure et simple entre une voie d'écoulement principale et une voie d'écoulement secondaire de section plus petite, pour le fluide refoulé par le piston, mais une commutation progressive entre ces deux voies d'écoulement afin de supprimer tout phénomène oscillatoire qui pourrait accompagner la décélération et/ou l'accélération du piston.The object of the invention is to eliminate this drawback, by ensuring not a pure and simple switching between a main flow path and a secondary flow path of smaller section, for the fluid discharged by the piston, but a switching progressive between these two flow paths in order to eliminate any oscillatory phenomenon which could accompany the deceleration and / or acceleration of the piston.

A cet effet, l'invention propose un dispositif de contrôle de la décélération et/ou de l'accélération d'un élément mobile suivant un mouvement alternatif rectiligne de va-et-vient, au voisinage d'au moins un des points morts de fin de course dudit élément mobile commandé, par exemple, par un fluide sous pression, comprenant deux pistons coaxialement alignés de diamètre différent coopérant respectivement, de façon étanche au voisinage du point mort considéré, avec deux cylindres coaxialement alignés et de diamètre différent, un des cylindres étant relié à une voie principale d'écoulement de fluide, l'autre cylindre étant relié à une voie secondaire calibrée d'écoulement de fluide de section moindre que la section de la voie principale d'éccu- lement de fluide, caractérisé en ce que le cylindre relié à la voie principale d'écoulement de fluide est obturé, de façon étanche,progressivement par le piston associé au fur et à mesure que ledit élément mobile se rapproche du point mort associé de sa course.To this end, the invention provides a device for controlling the deceleration and / or acceleration of a mobile element in a reciprocating rectilinear reciprocating movement, in the vicinity of at least one of the dead centers of end of travel of said movable element controlled, for example, by a pressurized fluid, comprising two coaxially aligned pistons of different diameter cooperating respectively, in a sealed manner in the vicinity of the dead center considered, with two coaxially aligned cylinders of different diameter, one of the cylinders being connected to a main fluid flow path, the other cylinder being connected to a calibrated secondary fluid flow path of smaller cross-section than the section of the main fluid flow path, characterized in that the cylinder connected to the main fluid flow path is closed, in a sealed manner, progressively by the associated piston as said moving element approaches the associated dead center of its course.

Selon une autre caractéristique de l'invention, le piston associé au cylindre de moindre diamètre est usiné de façon à ce que sa section transversale augmente au fur et à mesure que celui-ci pénètre dans son cylindre associé.According to another characteristic of the invention, the piston associated with the cylinder of smaller diameter is machined so that its cross section increases as it enters its associated cylinder.

Selon une autre caractéristique de l'invention, l'usinage précité consiste à effectuer un dégagement de matière dans le piston précité, comme par exemple un méplat incliné par rapport à la direction de l'élément mobile.According to another characteristic of the invention, the aforementioned machining consists in carrying out a release of material in the aforementioned piston, such as for example a flat inclined with respect to the direction of the movable element.

Selon une autre caractéristique de l'invention, l'usinage précité est effectué au niveau de l'alésage de moindre section, de façon à ce que la section transversale de cet alésage diminue au fur et à mesure que le piston associé pénètre dans cet alésage.According to another characteristic of the invention, the aforementioned machining is carried out at the bore of smaller section, so that the cross section of this bore decreases as the piston associated enters this bore.

D'autres avantages, caractéristiques et détails apparaîtront plus clairement à l'aide de la description explicative qui va suivre faite en référence aux dessins annexés donnés uniquement à titre d'exemple et dans lesquels :

  • La figure 1 est une vue en coupe longitudinale d'un vérin à double effet équipé d'un dispositif de contrôle conforme à l'invention; la figure 2 est une vue en coupe suivant la ligne II-II de la figure 1; et la figure 3 est une vue en coupe suivant la ligne III-III de la figure 1.
Other advantages, characteristics and details will appear more clearly with the aid of the explanatory description which follows, given with reference to the appended drawings given solely by way of example and in which:
  • Figure 1 is a longitudinal sectional view of a double-acting cylinder equipped with a control device according to the invention; Figure 2 is a sectional view along line II-II of Figure 1; and Figure 3 is a sectional view along line III-III of Figure 1.

En se reportant à la figure 1, le vérin 1 par exemple pneumatique et à double effet auquel s'applique l'invention est constitué d'un corps creux 2 ou cylindre dans lequel peut coulisser axialement un piston 3 dont la surface périphérique extérieure est en contact glissant étanche, par l'intermédiaire d'une garniture annulaire 4 de préférence du type à lèvre formant joint d'étanchéité porté par le piston 3, avec le cylindre 2.Referring to Figure 1, the cylinder 1, for example pneumatic and double-acting to which the invention applies, consists of a hollow body 2 or cylinder in which a piston 3 can slide axially, the outer peripheral surface of which is in tight sliding contact, by means of an annular lining 4 preferably of the lip type forming a seal carried by the piston 3, with the cylinder 2.

Le cylindre 2 du vérin est obturé à ses deux extrémités libres par deux blocs respectivement 5, 6.The cylinder 2 of the jack is closed at its two free ends by two blocks 5, 6 respectively.

Le bloc d'extrémité 5 ou fond du vérin 1 est traversé par un alésage borgne central 7 axialement aligné avec l'axe du piston 3. Cet alésage 7 communique vers son extrémité borgne avec un canal transversal 8 qui communique lui-même à son autre extrémité soit avec l'atmosphère soit avec une source de fluide sous pression (non représentée). Ce canal 8 joue le rôle de voie d'écoulement principale pour le fluide qui est refoulé par le piston 3.The end block 5 or bottom of the jack 1 is crossed by a central blind bore 7 axially aligned with the axis of the piston 3. This bore 7 communicates towards its blind end with a transverse channel 8 which communicates itself to its other end either with the atmosphere or with a source of pressurized fluid (not shown). This channel 8 acts as the main flow path for the fluid which is discharged by the piston 3.

A partir de la surface intérieure du fond 6 du vérin 1, adjacente au piston 3, est usiné un canal borgne 9 dans ledit fond, parallèlement à l'axe de l'alésage 7. L'extrémité de ce canal 9 communique avec un canal transversal 10 débouchant d'une part vers l'extérieur et d'autre part dans l'alésage 7. Dans ce canal 10 est montée une vis de réglage 11 pour régler l'écoulement de fluide passant par le canal 9 et se dirigeant vers l'alésage 7. Ce canal 9 et la partie du canal 10 située entre le canal 9 et l'alésage 7, constituent une voie d'écoulement secondaire pour le fluide refoulé par le piston 3. Il est important de noter que la section du canal 9 est notablement inférieure à la section du canal 8 qui communique soit avec l'atmosphère soit avec une source de fluide sous pression.From the inner surface of the bottom 6 of the jack 1, adjacent to the piston 3, a blind channel 9 is machined in said bottom, parallel to the axis of the bore 7. The end of this channel 9 communicates with a channel transverse 10 opening on the one hand towards the outside and on the other hand into the bore 7. In this channel 10 is mounted an adjusting screw 11 for regulating the flow of fluid passing through the channel 9 and going towards the bore 7. This channel 9 and the part of channel 10 located between channel 9 and bore 7, constitute a secondary flow path for the fluid discharged by the piston 3. It is important to note that the section of the channel 9 is significantly less than the section of the channel 8 which communicates either with the atmosphere or with a source of pressurized fluid.

Dans le fond 5 du vérin 1 peut être prévu un système de valve de décharge 12 réglable ou non, connu en soi, qui règle le débit de l'écoulement de fluide entre le cylindre 2 et l'extérieur par l'intermédiaire de deux canaux 13, 14 respectivement parallèle et perpendiculaire à l'axe du cylindre.In the bottom 5 of the cylinder 1 can be provided a discharge valve system 12 adjustable or not, known per se, which regulates the flow rate of the fluid flow between the cylinder 2 and the outside via two channels 13, 14 respectively parallel and perpendicular to the axis of the cylinder.

L'autre bloc d'extrémité 6 ou fond de vérin 1 est constitué d'une façon sensiblement identique au bloc d'extrémité 5. La seule différence réside dans le fait qu'il possède un second alésage 15 dans le prolongement de l'alésage 7 associé pour permettre à la tige 16 du piston 3 de faire saillie à l'extérieur du vérin 1.The other end block 6 or cylinder base 1 is constituted in a manner substantially identical to the end block 5. The only difference is that it has a second bore 15 in the extension of the bore 7 associated to allow the rod 16 of the piston 3 to protrude outside the jack 1.

De part et d'autre du piston 3 sont prévus respectivement deux bossages 17a, 17b axialement alignés avec l'axe du vérin 1 et qui possèdent une section transversale très légèrement inférieure à la section des alésages 7 dans lesquels ils sont destinés à pénétrer. Il est à noter que le bossage 17b du piston 3 se prolonge par la tige 16 du piston. Etant donné que ces bossages 17a, 17b sont destinés à coopérer de façon étanche avec les alésages 7 associés, il est prévu au niveau de chaque alésage 7 une garniture annulaire 18 formant joint d'étanchéité. Cette garniture 18 est par exemple montée au voisinage de l'extrémité ouverte de l'alésage 7 associé.On either side of the piston 3 are provided respectively two bosses 17a, 17b axially aligned with the axis of the cylinder 1 and which have a cross section very slightly less than the section of the bores 7 into which they are intended to penetrate. It should be noted that the boss 17b of the piston 3 is extended by rod 16 of the piston. Since these bosses 17a, 17b are intended to cooperate in leaktight fashion with the associated bores 7, an annular lining 18 forming a seal is provided at each bore 7. This packing 18 is for example mounted in the vicinity of the open end of the associated bore 7.

De façon à permettre une obstruction progressive de l'extrémité ouverte de chaque alésage 7 lorsque le bossage associé pénètre à l'intérieur dudit alésage, on prévoit au niveau de chaque bossage 17a, 17b au moins un dégagement de matière 19 tel que la section transversale de chaque bossage augmente au fur et à mesure que ce dernier pénètre dans son alésage 7 associé.In order to allow a progressive obstruction of the open end of each bore 7 when the associated boss penetrates inside said bore, at least one material clearance 19 such as the cross section is provided at each boss 17a, 17b. of each boss increases as the latter enters its associated bore 7.

Ce dégagement 19 peut être un méplat incliné suivant l'axe du piston, une fraisure ou une rainure de section carrée, arrondie, plane, en vé, et progressive d'une façon continue ou progressive par palier successifs sur toute ou partie de la longueur du bossage correspondant.This clearance 19 may be a flat inclined along the axis of the piston, a countersink or a groove of square section, rounded, flat, vee, and progressive in a continuous or progressive manner in successive stages over all or part of the length. of the corresponding boss.

Selon un second mode de réalisation du dispositif conforme à l'invention (tel que cela est représenté en traits mixtes sur la demi-vue inférieure de la figure 1), on peut avoir une inversion de structure, à savoir que la garniture annulaire 18' formant joint d'étanchéité entre le bossage et l'alésage associé est portée par le bossage, alors que le dégagement de matière 19' est prévu au niveau des alésages 7.According to a second embodiment of the device according to the invention (as shown in dashed lines in the lower half-view of FIG. 1), it is possible to have a structural inversion, namely that the annular lining 18 ' forming a seal between the boss and the associated bore is carried by the boss, while the material release 19 'is provided at the bores 7.

Il va être décrit maintenant en se reportant notamment à la figure 1, le fonctionnement du dispositif de contrôle conforme à l'invention.There will now be described with particular reference to FIG. 1, the operation of the control device according to the invention.

Lorsque le piston 3 se trouve entre ses deux points morts et sensiblement au-delà de ceux-ci, le piston 3 a une vitesse sensiblement constante et, suivant sa direction de déplacement, le fluide qu'il refoule est dirigé vers l'atmosphère, dans le cas d'un vérin pneumatique, en passant par l'alésage 7 correspondant non obturé et le canal 8 associé formant voie d'évacuation principale. Lorsque le piston 3 arrive au voisinage de son point mort situé du côté du fond 5 du vérin 1, et lorsque l'extrémité du bossage 17a arrive à proximité de l'entrée de l'alésage 7 associé, la voie de passage du fluide refoulé par le piston 3 en direction du canal d'évacuation 8 n'est que partiellement obturée, c'est-à-dire qu'une partie seulement du joint d'étanchéité 18 coopère avec la surface périphérique extérieure du bossage 17a. Dans cette position du piston 3, telle que représentée sur la figure 1, il est important, pour la suite de l'explication du fonctionnement, de considérer les deux chambres 20, 21 à volume variable correspondant respectivement à l'alésage 7 et au volume annulaire délimité entre le piston 3 et le fond 5 du vérin 1.When the piston 3 is between its two neutral points and substantially beyond them, the piston 3 has a substantially constant speed and, according to its direction of movement, the fluid which it discharges is directed towards the atmosphere, in the case of a pneumatic cylinder, passing through the corresponding bore 7 which is not closed and the associated channel 8 forming the main escape route. When the piston 3 arrives in the vicinity of its neutral point located on the side of the bottom 5 of the jack 1, and when the end of the boss 17a arrives close to the entry of the associated bore 7, the passageway for the pumped fluid by the piston 3 in the direction of the discharge channel 8 is only partially closed, that is to say that only part of the seal 18 cooperates with the outer peripheral surface of the boss 17a. In this position of the piston 3, as shown in FIG. 1, it is important, for the remainder of the explanation of the operation, to consider the two chambers 20, 21 with variable volume corresponding respectively to the bore 7 and to the volume annular delimited between the piston 3 and the bottom 5 of the jack 1.

Au fur et à mesure que le piston 3 avance vers son point mort de fin de course, le bossage 17a pénètre plus en avant à l'intérieur de l'alésage 7 associé en obturant progressivement de façon étanche cet alésage grâce au joint d'étanchéité annulaire 18 et ce, grâce au dégagement de matière 19 prévu au niveau du bossage 17a. Par conséquent, la voie principale d'échappement (chambre 20, canal 8) n'est pas obturée instantanément mais de façon progressive. Dans ces conditions, la pression croît alors lentement et progressivement dans la chambre 21 formant chambre d'amortissement, ce qui entraîne une décélération faible et continue du piston 3.As the piston 3 advances towards its end-of-travel dead center, the boss 17a penetrates further forward inside the associated bore 7 by progressively sealing this bore thanks to the seal annular 18 and this, thanks to the release of material 19 provided at the boss 17a. Consequently, the main escape route (chamber 20, channel 8) is not closed instantly but gradually. Under these conditions, the pressure then increases slowly and gradually in the chamber 21 forming the damping chamber, which causes a weak and continuous deceleration of the piston 3.

Au voisinage immédiat du point mort de la course du piston 3, l'alésage 7 est complètement obturé par le bossage 17a, c'est-à-dire que le joint d'étanchéité 18 coopère par toute sa surface avec la surface périphérique du bossage 17a. Le volume de la chambre d'amortissement 21 a considérablement diminué, et le peu de fluide qu'elle contient encore s'échappe vers l'atmosphère en s'écoulant à travers le canal longitudinal 9, le canal transversal 10, l'alésage et le canal d'échappement 8. Le débit de ce fluide peut être facilement réglé par l'intermédiaire de la vis de réglage 11. Le piston 3 est par conséquent toujours soumis à une décélération qui diminue progressivement, ce qui lui permet d'atteindre son point mort à une vitesse pratiquement nulle sans occasionner un quelconque choc mécanique.In the immediate vicinity of the neutral point of the stroke of the piston 3, the bore 7 is completely closed by the boss 17a, that is to say that the seal 18 cooperates through its entire surface with the peripheral surface of the boss 17a. The volume of the damping chamber 21 has considerably decreased, and the little fluid which it still contains escapes towards the atmosphere by flowing through the longitudinal channel 9, the transverse channel 10, the bore and the exhaust channel 8. The flow rate of this fluid can be easily adjusted by means of the adjusting screw 11. The piston 3 is therefore always subjected to a deceleration which gradually decreases, which enables it to reach its neutral at practically zero speed without causing any mechanical shock.

Lors de l'inversion du mouvement du piston 3, c'est-à-dire que le canal 8 du bloc d'extrémité 5 constitue maintenant un canal d'alimentation en fluide sous pression, le canal 8 associé à l'autre bloc d'extrémité 6 du cylindre 2 va communiquer avec l'atmosphère. Comme le piston 3 se trouve en phase d'accélération, le dégagement 19 prévu sur le bossage 17a permet d'admettre progressivement le fluide sous pression dans la chambre d'amortissement 21, ce qui permet d'éviter ainsi un brusque changement de débit lorsque le bossage 17a sera sorti de son alésage 7. De ce fait, une accélération progressive continue est assurée, sans décélération intempestive, durant cette phase de course avant la phase suivante où le piston 3 se déplace à une vitesse pratiquement constante. Ensuite, au voisinage de son autre point mort, le piston 3 sera décéléré par la coopération de son bossage 17b avec l'alésage 7 associé et ce, d'une façon identique à celle qui a été décrite précédemment.During the reversal of the movement of the piston 3, that is to say that the channel 8 of the end block 5 now constitutes a channel for supplying pressurized fluid, the channel 8 associated with the other block d end 6 of cylinder 2 will communicate with the atmosphere. As the piston 3 is in the acceleration phase, the clearance 19 provided on the boss 17a makes it possible to gradually admit the pressurized fluid into the damping chamber 21, which thus avoids a sudden change in flow when the boss 17a will be out of its bore 7. As a result, continuous progressive acceleration is ensured, without untimely deceleration, during this phase of racing before the next phase where the piston 3 moves at a practically constant speed. Then, in the vicinity of its other neutral point, the piston 3 will be decelerated by the cooperation of its boss 17b with the associated bore 7 and this, in a manner identical to that which has been described previously.

Il est à noter que pour le second mode de réalisation du dispositif de contrôle conforme à l'invention, c'est-à-dire avec les joints d'étanchéité portés respectivement par les bossages 17a, 17b, le principe de fonctionnement est rigoureusement identique.It should be noted that for the second embodiment of the control device according to the invention, that is to say with the seals carried respectively by the bosses 17a, 17b, the operating principle is strictly identical .

Le rôle du système de valve de décharge 12 auxiliaire est de permettre d'affaiblir la décélération du piston 3 en limitant la montée en pression dans la chambre d'amortissement, c'est-à-dire que son action s'ajoute à celle produite par les dégagements 19 prévus soit sur les bossages du piston soit dans les alésages avec lesquels coopèrent ces bossages.The role of the auxiliary relief valve system 12 is to make it possible to weaken the deceleration of the piston 3 by limiting the rise in pressure in the damping chamber, that is to say that its action is added to that produced by the clearances 19 provided either on the bosses of the piston or in the bores with which these bosses cooperate.

Il est à noter également que le dégagement de matière 19 tel qu'une fraisure ou rainure peut être réalisé aussi bien sur une génératrice du bossage (ou de l'alésage associé), parallèle à l'axe du piston, que sur une génératrice s'enroulant en hélice suivant un pas régulier ou non. Le seul impératif pour le dégagement 19 est d'assurer une obturation progressive de l'alésage associé.It should also be noted that the release of material 19 such as a countersink or groove can be produced both on a generator of the boss (or of the associated bore), parallel to the axis of the piston, and on a generator s '' winding in a helix according to a regular pitch or not. The only imperative for clearance 19 is to ensure progressive closure of the associated bore.

Dans les exemples décrits précédemment, il a été question d'un usinage soit au niveau du piston, soit au niveau du cylindre, mais il est possible d'usiner à la fois le piston et le cylindre pour assurer une fermeture progressive notamment de la voie principale d'écoulement de fluideoIn the examples described above, it was a question of machining either at the level of the piston, or at the level of the cylinder, but it is possible to machine both the piston and the cylinder to ensure a progressive closure in particular of the track main fluid flow

Un tel dispositif de contrôle s'applique aussi bien à un vérin à simple effet, et ne se limite pas à des vérins pneumatiques mais à tout vérin commandé en déplacement par tout fluide, et en particulier aux vérins hydrauliques.Such a control device applies equally well to a single-acting cylinder, and is not limited to pneumatic cylinders but to any cylinder controlled to move by any fluid, and in particular to hydraulic cylinders.

Bien entendu, l'invention n'est nullement limitée aux modes de réalisation qui n'ont été donnés et décrits qu'à titre d'exemple, mais comprend tous les équivalents techniques des moyens décrits ainsi que leurs combinaisons, si celles-ci sont réalisées et mises en oeuvre dans le cadre des revendications qui suivent.Of course, the invention is in no way limited to the embodiments which have been given and described only by way of example, but includes all the technical equivalents of the means described as well as their combinations, if these are produced and implemented in the context of the claims which follow.

Claims (12)

1. Dispositif de contrôle de la décélération et/ou de l'accélération d'un élément mobile suivant un mouvement alternatif rectiligne de va-et-vient, au voisinage d'au moins un des points morts de fin de course dudit élément mobile commandé, par exemple, par un fluide sous pression, comprenant deux pistons coaxialement alignés de diamètre différent coopérant respectivement, de façon étanche au voisinage du point mort considéré, avec deux cylindres coaxialement alignés et de diamètre différent, un des cylindres étant relié à une voie principale d'écoulement de fluide, l'autre cylindre étant relié à une voie secondaire calibrée d'écoulement de fluide de section moindre que la section de la voie principale d'écoulement de fluide,
caractérisé en ce que le cylindre relié à la voie principale d'écoulement de fluide est obturé progressivement de façon étanche par le piston associé au fur et à mesure que ledit élément mobile se rapproche du point mort considéré.1. Device for controlling the deceleration and / or acceleration of a movable element in a reciprocating rectilinear reciprocating movement, in the vicinity of at least one of the end of travel dead centers of said controlled movable element , for example, by a pressurized fluid, comprising two coaxially aligned pistons of different diameter cooperating respectively, in a sealed manner in the vicinity of the dead center considered, with two coaxially aligned cylinders of different diameter, one of the cylinders being connected to a main track fluid flow, the other cylinder being connected to a calibrated secondary fluid flow channel of smaller section than the section of the main fluid flow channel,
characterized in that the cylinder connected to the main fluid flow path is progressively closed in a sealed manner by the associated piston as and when said movable element approaches the dead center considered. 2. Dispositif selon la revendication 1,
caractérisé en ce que le piston précité associé à la voie principale d'écoulement de fluide est usiné de façon à ce que sa section transversale augmente au fur et à mesure que ledit piston pénètre dans ledit cylindre.2. Device according to claim 1,
characterized in that the aforementioned piston associated with the main fluid flow path is machined so that its cross section increases as said piston enters said cylinder. 3. Dispositif selon la revendication 1 ou 2, caractérisé en ce que le cylindre précité associé à la voie principale d'écoulement de fluide est usiné de façon à ce que sa section transversale diminue au fur et à mesure que son piston associé le pénètre.3. Device according to claim 1 or 2, characterized in that the aforementioned cylinder associated with the main fluid flow path is machined so that its cross section decreases as its associated piston penetrates it. 4. Dispositif selon l'une des revendications précédentes, caractérisé en ce que la voie principale d'écoulement de fluide précité est obturée de façon progressive par son piston associé, par l'intermédiaire d'un dégagement de matière effectué au niveau dudit cylindre et/ou au niveau dudit piston.4. Device according to one of the preceding claims, characterized in that the main aforementioned fluid flow path is closed progressively by its associated piston, by means of a release of material carried out at the level of said cylinder and / or at said piston. 5. Dispositif selon la revendication 4,
caractérisé en ce que le dégagement de matière précité est constitué par au moins une fraisure ou rainure dont la section est variable.5. Device according to claim 4,
characterized in that the aforementioned release of material consists of at least one countersink or groove whose section is variable. 6. Dispositif selon la revendication 2, 3 ou 5, caractérisé en ce que la section précitée varie d'une façon uniforme.6. Device according to claim 2, 3 or 5, characterized in that the above section varies in a uniform manner. 7. Dispositif selon la revendication 5,
caractérisé en ce que la section précitée varie par paliers.7. Device according to claim 5,
characterized in that the above-mentioned section varies in stages. 8. Dispositif selon l'une des revendications 4 à 7, caractérisé en ce que le dégagement précité s'étend sur au moins une partie de la longueur du piston précité ou du cylindre précité.8. Device according to one of claims 4 to 7, characterized in that the aforementioned clearance extends over at least part of the length of the aforementioned piston or the aforementioned cylinder. 9. Dispositif selon l'une des revendications précédentes, caractérisé en ce que le piston précité de plus grand diamètre est constitué par le piston proprement dit d'un vérin, le piston précité de moindre diamètre étant constitué par un bossage prévu au niveau dudit piston et coaxialement aligné avec celui-ci.9. Device according to one of the preceding claims, characterized in that the aforementioned piston of larger diameter is constituted by the piston proper of a jack, the aforementioned piston of smaller diameter being constituted by a boss provided at said piston and coaxially aligned with it. 10. Dispositif selon la revendication 9, caractérisé en ce que le cylindre associé au piston du vérin précité est constitué par le cylindre dudit vérin, alors que le cylindre précité de moindre diamètre coopérant avec le bossage précité est constitué par un alésage borgne prévu dans le fond associé du vérin et est relié à la voie principale d'écoulement de fluide.10. Device according to claim 9, characterized in that the cylinder associated with the piston of the aforementioned cylinder is constituted by the cylinder of said cylinder, while the aforementioned cylinder of smaller diameter cooperating with the aforementioned boss is constituted by a blind bore provided in the associated bottom of the jack and is connected to the main fluid flow path. 11. Dispositif selon l'une des revendications précédentes,
caractérisé en ce qu'il peut comprendre également un système de valve de décharge auxiliaire éventuellement réglable.11. Device according to one of the preceding claims,
characterized in that it can also comprise an optionally adjustable auxiliary relief valve system. 12. Vérin du type hydraulique ou pneumatique, caractérisé en ce qu'il est équipé au voisinage de l'un ou de ses deux points morts de fin de course de sa tige de piston par un dispositif de contrôle de sa vitesse au voisinage du point mort considéré, tel que défini selon l'une des revendications précédentes.12. Cylinder of the hydraulic or pneumatic type, characterized in that it is equipped in the vicinity of one or of its two dead centers at the end of its piston rod stroke by a speed control device in the vicinity of the point death considered, as defined according to one of the preceding claims.
EP79400286A 1978-05-05 1979-05-04 End of stroke decelerating and/or accelerating means for rectilinear, alternating moving parts Withdrawn EP0005407A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR7813360 1978-05-05
FR7813360A FR2425008A1 (en) 1978-05-05 1978-05-05 DEVICE FOR CONTROLLING THE DECELERATION AND / OR ACCELERATION OF A MOBILE ELEMENT FOLLOWING A BACK-AND-BACK RIGGED ALTERNATIVE MOVEMENT, IN THE NEARBY OF AT LEAST ONE OF THE MOBILE ELEMENT LIMIT DEAD POINTS

Publications (1)

Publication Number Publication Date
EP0005407A1 true EP0005407A1 (en) 1979-11-14

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EP (1) EP0005407A1 (en)
FR (1) FR2425008A1 (en)

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2479389A1 (en) * 1980-03-26 1981-10-02 Komatsu Mfg Co Ltd HYDRAULIC CYLINDER STROKE DAMPING DEVICE
DE3441005A1 (en) * 1983-11-16 1985-05-30 Wabco Westinghouse Gmbh, Wien Pneumatic working cylinder with pneumatic end-position damping
FR2565638A1 (en) * 1984-06-11 1985-12-13 Nippon Joucomatic Co Ltd PNEUMATIC CYLINDER COMPRISING A DECELERATION MECHANISM
EP0199556A1 (en) * 1985-04-20 1986-10-29 Colt International Limited Pneumatic actuator
GB2278642A (en) * 1993-06-03 1994-12-07 Mannesmann Ag Piston and cylinder device
EP0648941A1 (en) * 1993-10-18 1995-04-19 UNIVER S.p.A. Pneumatic actuator with adjustable stop and damping device
US5456469A (en) * 1995-01-17 1995-10-10 Macdougall; Alexander S. Dynamically stabilized golf club
EP0778107A1 (en) * 1995-12-05 1997-06-11 TÜNKERS MASCHINENBAU GmbH Toggle lever clamp
EP0790413A2 (en) * 1996-02-13 1997-08-20 Ab Rexroth Mecman Cylinder device
NL1007965C2 (en) * 1998-01-06 1999-07-07 Zuidberg Techniek B V Control system for a vehicle clutch, in a vehicle equipped with a hydraulic system
EP1041293A2 (en) 1999-03-29 2000-10-04 Luciano Migliori Pneumatic cylinder with damping device
EP1074750A2 (en) 1999-08-04 2001-02-07 UNIVER S.p.A. Pressure fluid actuator with damping and speed control device
WO2001090585A1 (en) * 2000-05-24 2001-11-29 Johann Weiss Maschinenbau Pneumatic cylinder with damping in the end position
EP1199480A2 (en) 2000-10-16 2002-04-24 Luciano Migliori Compact pneumatic cylinder, with cushioning device
EP0974769A3 (en) * 1998-07-22 2003-01-02 Hainzl Industriesysteme Gesellschaft m.b.H. & Co. KG Device for the braking of a piston in a hydraulic cylinder
FR2828519A1 (en) * 2001-08-09 2003-02-14 Peugeot Citroen Automobiles Sa Damping device assisting displacement of automobile door comprises piston in cylinder delimiting two chambers, piston activating circuit and piston hydraulic braking circuit
CN103629188A (en) * 2013-12-11 2014-03-12 四川凌峰航空液压机械有限公司 Buffer device for actuator drum
CN104963908A (en) * 2015-05-13 2015-10-07 中航飞机起落架有限责任公司 Actuator cylinder of integrated variable damping device
EP3205891A1 (en) * 2016-02-09 2017-08-16 FESTO AG & Co. KG Fluid actuated linear unit
CN110539883A (en) * 2019-07-23 2019-12-06 北京精密机电控制设备研究所 Undercarriage receive and releases executor
CN113775594A (en) * 2020-06-10 2021-12-10 Smc 株式会社 Cylinder

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2696743B2 (en) * 1993-12-09 1998-01-14 エスエムシー株式会社 Rodless cylinder with speed control mechanism

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1410314A (en) * 1964-07-22 1965-09-10 Improvements to hydraulic cylinders, in particular for automatic control of machines or the like
US3559535A (en) * 1969-01-21 1971-02-02 Patrick W Conolly Hydraulic cylinder with cushioned stroke
DE2240980A1 (en) * 1972-08-21 1974-03-07 Adam Dipl Ing Elmer DEVICE FOR DAMPING THE PISTON IMPACT IN HYDRAULIC WORK CYLINDERS
DE2254495A1 (en) * 1972-11-07 1974-05-22 Zettelmeyer Fa Hubert DEVICE FOR DAMPING THE STRIKING OF EACH OTHER MOVING PARTS COUPLED BY HYDRAULIC CYLINDERS
DE2402567A1 (en) * 1974-01-19 1975-07-24 Kuhnke Gmbh Kg H End position damping for hydraulic and pneumatic motors - damping chamber formed in motor cylinder is sealed with respect to main outlet bore
DE2531394A1 (en) * 1974-07-15 1976-01-29 Parker Hannifin Corp HYDRAULIC BRAKE DEVICE

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1410314A (en) * 1964-07-22 1965-09-10 Improvements to hydraulic cylinders, in particular for automatic control of machines or the like
US3559535A (en) * 1969-01-21 1971-02-02 Patrick W Conolly Hydraulic cylinder with cushioned stroke
DE2240980A1 (en) * 1972-08-21 1974-03-07 Adam Dipl Ing Elmer DEVICE FOR DAMPING THE PISTON IMPACT IN HYDRAULIC WORK CYLINDERS
DE2254495A1 (en) * 1972-11-07 1974-05-22 Zettelmeyer Fa Hubert DEVICE FOR DAMPING THE STRIKING OF EACH OTHER MOVING PARTS COUPLED BY HYDRAULIC CYLINDERS
DE2402567A1 (en) * 1974-01-19 1975-07-24 Kuhnke Gmbh Kg H End position damping for hydraulic and pneumatic motors - damping chamber formed in motor cylinder is sealed with respect to main outlet bore
DE2531394A1 (en) * 1974-07-15 1976-01-29 Parker Hannifin Corp HYDRAULIC BRAKE DEVICE

Cited By (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2479389A1 (en) * 1980-03-26 1981-10-02 Komatsu Mfg Co Ltd HYDRAULIC CYLINDER STROKE DAMPING DEVICE
DE3441005A1 (en) * 1983-11-16 1985-05-30 Wabco Westinghouse Gmbh, Wien Pneumatic working cylinder with pneumatic end-position damping
FR2565638A1 (en) * 1984-06-11 1985-12-13 Nippon Joucomatic Co Ltd PNEUMATIC CYLINDER COMPRISING A DECELERATION MECHANISM
EP0199556A1 (en) * 1985-04-20 1986-10-29 Colt International Limited Pneumatic actuator
GB2278642B (en) * 1993-06-03 1997-03-19 Mannesmann Ag Piston and cylinder device
FR2705999A1 (en) * 1993-06-03 1994-12-09 Mannesmann Ag Cylinder device.
GB2278642A (en) * 1993-06-03 1994-12-07 Mannesmann Ag Piston and cylinder device
EP0648941A1 (en) * 1993-10-18 1995-04-19 UNIVER S.p.A. Pneumatic actuator with adjustable stop and damping device
US5456469A (en) * 1995-01-17 1995-10-10 Macdougall; Alexander S. Dynamically stabilized golf club
EP0778107A1 (en) * 1995-12-05 1997-06-11 TÜNKERS MASCHINENBAU GmbH Toggle lever clamp
EP0790413A2 (en) * 1996-02-13 1997-08-20 Ab Rexroth Mecman Cylinder device
EP0790413A3 (en) * 1996-02-13 1998-06-17 Ab Rexroth Mecman Cylinder device
NL1007965C2 (en) * 1998-01-06 1999-07-07 Zuidberg Techniek B V Control system for a vehicle clutch, in a vehicle equipped with a hydraulic system
EP0974769A3 (en) * 1998-07-22 2003-01-02 Hainzl Industriesysteme Gesellschaft m.b.H. & Co. KG Device for the braking of a piston in a hydraulic cylinder
US6382074B1 (en) 1999-03-29 2002-05-07 Luciano Migliori Pneumatic cylinder with damping device
EP1041293A2 (en) 1999-03-29 2000-10-04 Luciano Migliori Pneumatic cylinder with damping device
EP1074750A2 (en) 1999-08-04 2001-02-07 UNIVER S.p.A. Pressure fluid actuator with damping and speed control device
WO2001090585A1 (en) * 2000-05-24 2001-11-29 Johann Weiss Maschinenbau Pneumatic cylinder with damping in the end position
EP1199480A2 (en) 2000-10-16 2002-04-24 Luciano Migliori Compact pneumatic cylinder, with cushioning device
US6553889B2 (en) 2000-10-16 2003-04-29 Luciano Migliori Compact pneumatic cylinder, with cushioning device
FR2828519A1 (en) * 2001-08-09 2003-02-14 Peugeot Citroen Automobiles Sa Damping device assisting displacement of automobile door comprises piston in cylinder delimiting two chambers, piston activating circuit and piston hydraulic braking circuit
CN103629188A (en) * 2013-12-11 2014-03-12 四川凌峰航空液压机械有限公司 Buffer device for actuator drum
CN103629188B (en) * 2013-12-11 2016-07-13 四川凌峰航空液压机械有限公司 Buffer device for actuator drum
CN104963908A (en) * 2015-05-13 2015-10-07 中航飞机起落架有限责任公司 Actuator cylinder of integrated variable damping device
EP3205891A1 (en) * 2016-02-09 2017-08-16 FESTO AG & Co. KG Fluid actuated linear unit
CN110539883A (en) * 2019-07-23 2019-12-06 北京精密机电控制设备研究所 Undercarriage receive and releases executor
CN113775594A (en) * 2020-06-10 2021-12-10 Smc 株式会社 Cylinder
EP3922864A1 (en) * 2020-06-10 2021-12-15 SMC Corporation Gas cylinder
CN113775594B (en) * 2020-06-10 2024-04-05 Smc株式会社 Cylinder

Also Published As

Publication number Publication date
FR2425008A1 (en) 1979-11-30
FR2425008B1 (en) 1982-02-19

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