BE403283A

BE403283A -

Info

Publication number: BE403283A
Authority: BE

Description

       

   <Desc/Clms Page number 1> 
 



    Il   Procédé d'obturation pour pistons Il 
La présente invention se rapporte à des moyens spéciale- ment adaptés pour l'obturation de pistons de mécanisme de frei- nage actionnés par une pression de fluide réalisée et appliqués par un mécanisme de commande actionné soit à la main, soit au pied, soit ensemble à la main et au pied. 



   Le dessin annexé représente, à titre d'exemple, un mode de réalisation de la présente invention. Dans ce dessin: 
La figure   1   est une vue en coupe en élévation, montrait   l'Obturation   et le piston en deux positions, celle   oorrespon-   dant approximativement aux conditions existant lorsque les   sa-   bots de frein sont desserrés ou "ouverts" étant représentée à gauche, la position du piston et de l'obturation lorsque les freins sont appliqués ou "fermés"étant approximativement indi- quée à droite, la différence de position dans les deux cas de 

 <Desc/Clms Page number 2> 

 freinage "ouvert et "fermé,

   indiquant que le mouvement radial maximum vers l'extérieur des organes de piston par   ltintermédiai-   re desquels la pression de fluide agit sur les sabots de frein est relativement faible, même lorsque les garnitures de frein sont usées. 



   La figure 2 est une vue par-dessous de 1'obturation mon- trant 1'espace annulaire entre ses parois latérales doubles,   mong   tantes, et disposées concentriquement,, 
La figure 3 est une vue en coupe de la bague métallique de renforcement noyée dans la bride dt obturation pour   rési@ter     à   l'effort de serrage périphérique qui se produit lorsque la corps de cylindre est vissé dans l'évidement fileté servant de tête ou extrémité fermée du. cylindre dans lequel se meut le piston obturé. 



   La figure 4 montre une variante,   légèrement   différente,, d'obturation pour un piston de compresseur dont la tête est plus abaissée, nécessitant ainsi un emboîtage plus profond da   l'obturation,   laquelle, par ailleurs, est identique à   cella        présentés sur la figure 1 et s'applique de la même façon, 
Dans la figure 1, le support 1 du cylindre est creusé et fileté de façon à recevoir l'extrémité interne ou "tête" du corps de cylindre 2 dans lequel le piston 3   à   tête étagée effec- tue un mouvement de va-.et-vient, le large bourrage 4 conser- vant la petite quantité de lubrifiant nécessaire pour   empêcher   le coincement du léger mouvement auquel est soumis le piston. 



   L'obturateur élastique 5 est en matière flexible renfort cée sur la périphérie par une bague 6 résistante sous laquelle est placé un joint 7, les espaces 8 et 9 étant remplis lorsque le fluide sous pression est poussé   à   travers le passage 10 par un compresseur extérieur ayant un cylindre et un piston aux- quels est appliqué le même type d'obturation. 

 <Desc/Clms Page number 3> 

 



   La bague de renforcement 6 a une section découpée comme l'indique la figure 3, à plus grande échelles Elle est large- ment enfouie dans la matière flexible de l'obturation à laquelle elle adhère fortement, conférant ainsi à son rebord circonfé- rentiel en saillie la rigidité absolue nécessaire, pour   l'enser-   rer entre la tête de cylindre 3 et un joint sous-jacent   7   dispo- sé à la partie inférieure de l'évidement fileté du support dans lequel se trouve vissée l'extrémité du cylindre.

   La matière déformable de l'obturateur 5 a la forme d'une coupe double pour   se. conformer   à celle intérieure de la tête de piston et à la forme, extérieure du creux de cylindre, un espace annulaire étant constitué entre les faces intérieures concentriques des parois intérieure et extérieure de la coupe, cette dernière paroi ayant une bride de serrage renforcée, d'une seule pièce avec elle, dans laquelle le bord arrondi du corps de cylindre se trouve fortement pressé lorsqu'il est vissé, en place contre le bord supérieur de la bague de renforcement 6 obturée par joint 7'. 
 EMI3.1 
 



  La résistance à la pression contre les parois f-1aa:iI\1 bzz de l'obturation est fournie par la tête de piston et les dt16 "$,   ooaxialement   disposées du cylindre et du piston, la déformation de l'obturation qui a lieu lorsque le piston se déplace n'ayant aucune action nuisible sur   l'efficacité   de l'obturation pour empêcher la fuite du fluide et, par suite, la perte de pression*



   <Desc / Clms Page number 1>
 



    Il Sealing process for pistons Il
The present invention relates to means specially adapted for the closure of braking mechanism pistons actuated by a fluid pressure produced and applied by a control mechanism actuated either by hand, or by foot, or together. by hand and foot.



   The accompanying drawing shows, by way of example, an embodiment of the present invention. In this drawing:
Figure 1 is a sectional elevational view, showing the shutter and piston in two positions, that approximately corresponding to the conditions existing when the brake shoes are released or "open" being shown at left, the position of the piston and the shutter when the brakes are applied or "closed" being approximately indicated on the right, the difference in position in the two cases of

 <Desc / Clms Page number 2>

 "open and" closed braking,

   indicating that the maximum radial outward movement of the piston members through which the fluid pressure acts on the brake shoes is relatively small, even when the brake linings are worn.



   Figure 2 is a view from below of the shutter showing the annular space between its concentrically arranged double side walls.
Figure 3 is a sectional view of the reinforcing metal ring embedded in the shutter flange to resist the peripheral clamping force which occurs when the cylinder body is screwed into the threaded recess serving as a head or closed end of. cylinder in which the closed piston moves.



   Figure 4 shows a slightly different variant of the closure for a compressor piston whose head is lowered, thus requiring a deeper fitting of the closure, which, moreover, is identical to that shown in the figure. 1 and applies in the same way,
In Figure 1, the cylinder support 1 is hollowed out and threaded so as to receive the inner end or "head" of the cylinder body 2 in which the stepped head piston 3 performs a back and forth movement. comes, the large packing 4 retaining the small quantity of lubricant necessary to prevent the jamming of the slight movement to which the piston is subjected.



   The elastic shutter 5 is made of flexible material reinforced on the periphery by a strong ring 6 under which is placed a seal 7, the spaces 8 and 9 being filled when the pressurized fluid is pushed through the passage 10 by an external compressor having a cylinder and a piston to which the same type of seal is applied.

 <Desc / Clms Page number 3>

 



   The reinforcing ring 6 has a section cut as shown in figure 3, on a larger scale. It is largely buried in the flexible material of the seal to which it strongly adheres, thus giving its circumferential rim protrudes the necessary absolute rigidity, to enclose it between the cylinder head 3 and an underlying seal 7 arranged at the lower part of the threaded recess of the support in which the end of the cylinder is screwed.

   The deformable material of the shutter 5 has the shape of a double cup for itself. conform to the inner one of the piston head and to the outer shape of the cylinder hollow, an annular space being formed between the concentric inner faces of the inner and outer walls of the cup, the latter wall having a reinforced clamping flange, d 'one piece with it, in which the rounded edge of the cylinder body is strongly pressed when screwed, into place against the upper edge of the reinforcing ring 6 sealed by seal 7'.
 EMI3.1
 



  The resistance to pressure against the walls f-1aa: iI \ 1 bzz of the shutter is provided by the piston head and the dt16 "$, ooaxially arranged of the cylinder and the piston, the deformation of the shutter which takes place when the piston moves having no detrimental effect on the effectiveness of the seal to prevent fluid leakage and, consequently, pressure loss *

Claims

CLAIMS 1 - Means for closing a piston actuated by a fluid, with respect to. cylinder hollow in which said piston moves, comprising a flexible circular seal consisting of a molded body having a stress-resistant reinforcing ring, of an angular section embedded in the peripheral rim projecting from the body and cemented in aelui-ai, said body having a wall which folds on itself to constitute inner and outer concentric walls, housed between the hollow of the cylinder and a peripheral wall of the piston, the inner wall comprising a bottom intended to overcome the end of the piston.,

the closure thus arranged having the space between the concentric walls open towards the chamber of the cylinder facing the fluid, to subject said walls to the fluid pressure, actuating the piston, applied to move the piston relative to the end cylinder, causing pressure to maintain body walls in sealed contact with piston and cylinder.

2 - A flexible obturation molded so as to s' @@@@@ @ at the head of a piston and at the hollow of the cylinder in which said piston alternately moves, said obturation comprising a wall folded back on itself to form inner and outer concentric walls, the outer wall of said closure having a projecting peripheral rim against which the end forming the head of said cylinder is strongly pressed, a cut-out reinforcing ring of angular section, embedded and cemented in said flange and integral with the latter, said concentric walls being intended to bear, respectively, on the side of the piston head and on the inner wall of the cylinder,

the space between the concentrated walls being open to allow access of the fluid pressure between said walls. <Desc / Clms Page number 5>

3 ,, A circular, flexible obturation, in the form of a double cup, having concentric and integral peripheral walls inside and outside, spaced apart from each other receiving, respectively, the head of a piston and the wall of the hollow ' of a cylinder within which moves, alternatively, said piston, the outer wall of the closure having a projecting oiroonferential rim against which is pressed, in a sealed manner, the head of said cylinder, said flange comprising a cut-out reinforcing ring of angular section, embedded and cemented in the sealing material, to transfer the major part of the clamping force acting on this flange to.

an underlying seal and to the cylinder support, an annular space being provided between the inner and outer peripheral walls of said sealing to receive the pressurized fluid, to force said walls to come into tight contact with said piston and cylinder.

4 è Means for closing a piston actuated by a fluid relative to the cylinder, in which it moves, comprising a resilient sealing element having the general shape of a cup to overcome the end of the piston, with the wall of the cup disposed between the piston and the cylinder, said cutting wall being hollowed out internally on the opposite side of the element to receive the fluid pressure in the direction of movement of the piston, said element having a peripheral reinforcing member, metallic , attached thereto, intended to be placed by the cylinder, the fluid pressure moving the piston acting at the same time so as to deform the wall of the element.

6'On An element according to claim 4, characterized in that the metal reinforcing member has an annular shape, the outer diameter of which is greater than the diameter of. hollow of the cylinder. <Desc / Clms Page number 6>

6 - An element according to claim 4, characterized EMI6.1 that this element is mou7.é and 1 ô rentoraement in that this element is molded and the reinforcing member has an annular shape and an internal section such that it can engage with the neighboring part of the element. EMI6.2 ment and protect the effiaacit, é from plugging during the golden movement of the piston.