(19)
(11) EP 3 177 443 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
19.09.2018 Bulletin 2018/38

(21) Application number: 14777175.2

(22) Date of filing: 06.08.2014
(51) International Patent Classification (IPC): 
B28D 1/08(2006.01)
B28D 1/12(2006.01)
B27B 33/14(2006.01)
(86) International application number:
PCT/IB2014/063733
(87) International publication number:
WO 2016/020722 (11.02.2016 Gazette 2016/06)

(54)

CHAIN FOR SAW MACHINES FOR CUTTING ORNAMENTAL STONES, ADAPTED TO PREVENT THE ENTRANCE OF IMPURITIES BETWEEN THE INTERNAL LINK AND THE EXTERNAL LINK OF THE CHAIN

KETTE FÜR SÄGEMASCHINEN ZUM SCHNEIDEN VON ZIERSTEINEN MIT ANPASSUNG ZUR VERHINDERUNG DES EINDRINGENS VON VERUNREINIGUNGEN ZWISCHEN DAS INNERE GLIED UND DAS ÄUSSERE GLIED DER KETTE

CHAÎNE POUR MACHINE À SCIER POUR COUPER DES PIERRES D'ORNEMENT, CONÇUE POUR EMPÊCHER L'ENTRÉE D'IMPURETÉS ENTRE LA LIAISON INTERNE ET LA LIAISON EXTERNE DE LA CHAÎNE


(84) Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated Extension States:
BA ME

(43) Date of publication of application:
14.06.2017 Bulletin 2017/24

(73) Proprietor: Fantini Sud S.p.A.
03012 Anagni (FR) (IT)

(72) Inventor:
  • FANTINI, Luigi
    I-03012 Anagni (FR) (IT)

(74) Representative: Fiammenghi, Eva et al
Fiammenghi - Fiammenghi Via delle Quattro Fontane, 31
00184 Roma
00184 Roma (IT)


(56) References cited: : 
WO-A1-2008/041263
DE-A1- 19 937 570
US-A- 2 762 227
US-A- 5 226 404
DE-A1- 4 237 781
DE-C- 706 560
US-A- 5 123 400
   
       
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    Field of the art



    [0001] The present invention generally refers to the saw machines for cutting ornamental stones, such as those normally used in ornamental stone extraction quarries (marble, etc). More particularly, it relates to an improvement of the chain of the chain saw machine, such chain being as usual formed by internal links and external links that carry the cutting inserts.

    [0002] The inventive concept of the present invention is generally applicable to chains with all types of insert holders and cutting inserts, to any type of arrangement of cutting inserts on the chain, to all types of methods for applying the insert on the insert holder (removable type and otherwise), since it only regards a system for preventing the entrance of mud, dust or the like, in the internal upper part of the external link. A cutting chain according to the preamble of claim 1 is known from WO2008/041263.

    Prior art



    [0003] It is known that each time the chain rotates around the pinion of the arm of the saw, or around the toothed transmission wheel situated at the free end of the arm itself, in the chain of the prior art, a small opening or passage is created between an internal link and a contiguous external link, where dust, mud or the like can easily penetrate during the cutting of the ornamental stone. Over time, the mass of mud that penetrated inside the external link is hardened, creating a thickness on the top internal part of the external link, below the upper wall of the external link that carries the cutting insert. Such thickness of extraneous, unwanted material in the long term prevents the precise closure, i.e. the exact alignment between the links of the chain along the substantially rectilinear section traveled by the chain within the guide obtained on the arm of the saw. This clearly induces stresses on the articulation pin between the links, which are added to the classical tensile stresses (inevitable since they are due to the normal operation of the chain saw machine). The articulation pin may then be broken.

    [0004] Hence, one object of the present invention is to remedy such drawback of the prior art, by suitably modifying the shape of the internal link and that of the external link on the internal part thereof that receives the internal link.

    [0005] In a specific embodiment of the present invention, the external link is composed of two parts. This allows using specific articulation pins, which, having an intermediate part with greater diameter than the ends thereof, prevent any risk that the pin can exit from the chain.

    Brief description of the drawings



    [0006] The present invention will now be illustrated in more detail only as a non-limiting or non-binding example, with reference to the enclosed drawings, which show:

    FIGURE 1 (1a to 1e): various views of a first embodiment of the present invention, in which the external link is formed by a single piece;

    FIGURE 2 (2a to 2d): various views of the same embodiment of the invention already represented in Fig. 1, which comprise in particular an exploded view and two operation views of the chain;

    FIGURE 3 (3a to 3e): various views of the second embodiment of the invention, in which the external link is formed by two modular parts;

    FIGURE 4 (4a to 4e): various views of the invention, analogous to Fig. 1, but for the second embodiment of the present invention;

    FIGURE 5 (5a to 5c): the operation and the exploded perspective view for the second embodiment of the present invention;

    FIGURE 6 (6a to 6c): various views of the first modular part (or front part) of the external link of the second embodiment of the present invention;

    FIGURE 7 (7a to 7d): various views of the second modular part (or rear part) of the external link of the second embodiment of the present invention;

    FIGURE 8 (8a to 8c): various views of the internal link of the present invention.


    Detailed description of several preferred embodiments of the invention



    [0007] The present invention will now be described in a rather detailed manner, so that a man skilled in the art can fully comprehend the significance and inventive concept thereof.

    [0008] Nevertheless, it is not necessary to enter into those details which are in any case obvious for a man skilled in the art; in particular, the latter will immediately understand that the present invention is applicable to all known materials in the field, as well as to all types of inserts, insert holders, of insert arrangement on the chain, of insert shape, to all insert assembly types (welded or removable insert), etc.

    [0009] Hence, turning our attention to the specific problem resolved by the present invention, the inventor of the present invention first of all observed the drawback due to the entrance of mud, dust or other impurities, through the opening that is formed between the external link and the internal link at the time when the links rotate with respect to each other, i.e. during the step of rotating the chain around the actuation pinion and respectively around the transmission wheel placed at the free end of the arm of the saw.

    [0010] In conventional chains, the size of this opening that came to be created in this step of revolution of the chain around the arm was such to allow a gradual accumulation of extraneous, unwanted material inside the external link, in proximity of the articulation pin; in the long term, such material formed, as already stated above, a layer of hard material ("crust" or "thickness"), for example of hardened mud or the like, which prevented a precise realignment of the links of the chain along the rectilinear path (within the guides of the arm). The stresses on the articulation pin, deriving from this undesired effect, being added to the "physiological" tensile stresses due to the normal operation of the chain, considerably contributed to reducing the average lifetime of the articulation pin.

    [0011] The inventor of the present invention resolved such technical problem by using a particular shape of the internal link and external link. This particular configuration of the links first of all allows reducing to a minimum the size of the aforesaid opening, and in addition forms a labyrinth path that further prevents the entrance of mud or the like. It follows that the extraneous material that could still enter inside the external link (after this modification of the shape of the links) in any case corresponds to a null or negligible quantity, whose effect is thus null or insignificant. Above all, due to the present invention, the gradual accumulation over time of a thickness of extraneous material, with harmful effect on the articulation pin, is prevented in a reliable manner.

    [0012] The present general inventive concept is equally applicable - as will be seen - to both the conventional external links obtained in a single piece, and to a particular type of innovative modular external link. In the latter case, it is possible to use anti-unthreading articulation pins having a central part with greater diameter than the external terminal portions of the pin. With reference to Figs. 1 and 2, the first embodiment of the invention will now be described, in which the external link is made of a single piece.

    [0013] In figures 1 and 2, reference number 1 indicates the internal link, 2 the external link, 3 the articulation pin, in which in particular Fig. 1c is the vertical section A-A of Fig.1a passing through this articulation pin 3 between the links 1 and 2. The man skilled in the art knows that the configuration shown in Fig. 1a is repeated along the entire continuous cutting chain, though in order to simplify the drawings only two contiguous links 1 and 2 are shown (the links 1 and 2 being of course alternated, giving rise to the cutting chain).

    [0014] In the prior art, the external link has a substantially U-shaped cross section which is constant, i.e. it internally forms a rectangular space with constant free section. Therefore, when an internal link is tilted with respect to an external link, for example at the toothed transmission wheel or at the actuation pinion (as in Figs. 2a and 2d, which refer however to the present invention), an opening is formed for the entrance of mud, dust or the like, between the two links, with the aforesaid consequences that compromise the integrity of the chain.

    [0015] In addition, the conventional internal link has rectilinear form at the top and bottom, while it is substantially round (i.e. arc of a circle) at the ends that join the upper and lower rectilinear sides.

    [0016] According to the present invention, however, the upper side of the internal link 1 forms a recess 4 that is extended between the round ends 5, 5', while the rectilinear lower side 6 of the internal link 1 preferably does not have any recess, or at least such recess is not necessary. In Fig. 2a, the dashed line 7 schematically indicates the shape of the conventional internal link on its upper side.

    [0017] Also the external link 2 of the present invention is radically modified with respect to the conventional external link. Indeed, it no longer has a constant internal section, but rather it is solid in the shaded part 8 - which also comprises a projection or barrier 9 against the entrance of mud, dust or the like - and is void i.e. free in the white part 10 (lacking shading) in Fig. 2a. Fig. 2a shows a section on a side wall 11 of the external link 2, which underlines the longitudinal section B-B (see Fig. 2c) executed in the longitudinal vertical plane of symmetry of the external link 2. The shaded part 8 indicates the material itself of the external link 2 which joins together the opposite side walls 11, 11' of the external link 2. Therefore, it is understood that the free internal section 10 of the external link 2 is reduced to a minimum height "d" (Fig. 2a) in the central part of the external link 2, while at the two ends of the external link 2 it has a curved (substantially circular) form 12, even if this is only shown for one of the articulation holes 14. Hence, the external link 2 of the invention internally has two concavities 12 that are separated from each other by a flat/rectilinear section 13 (Fig. 2a). Overall, each of the concavities 12 has a progression such to match the substantially curved-circular shape of the round end 5 (5') of the respective internal link 1, but preferably there is an abutment 16 that limits the maximum tilt angle ϕmax between the links 1, 2 (e.g. ϕmax = approximately 30°).

    [0018] The (steel) material of the shaded part 8, which is continuous with that of the projection or barrier 9 against the entrance of impurities, therefore gives rise to a minimum interspace between the internal link 1 and the bottom of the concavity 12 of the external link 2; in addition, for all the angular positions ϕ ≤ ϕmax between the internal link 1 and the external link 2, this interspace is constant and insignificant. Even if mud or the like should penetrate into the aforesaid interspace, it could never be accumulated over time to form a hard, substantial thickness. In particular, it is noted that the recess 4, receiving the barrier 9, allows the complete alignment rotation of the internal link 1 with respect to the external link 2 (which would otherwise be impossible), while, on the other hand, the barrier 9 has the aforesaid effect of preventing the entrance of impurities.

    [0019] In summary, the man skilled in the art clearly understands the labyrinth function carried out by the barrier 9 and in particular by the concavity 12 against the entrance of impurities; such barrier and concavity cooperate with the particular shape ("bone-like" form) of the internal link 1. Hence, the entrance of impurities is prevented in the direction of the arrow F of Fig. 2d, between the internal link 1 and the external link 2.

    [0020] Fig. 2d shows the aligned position of the links and that corresponding to ϕmax.

    [0021] Fig. 2c is the plan view of Fig. 2d, while in the exploded view (Fig. 2b), one observes the separated links and one of the articulation pins 3 knurled in the central part 17 in order to improve the effect of checking/locking in the respective hole 18 of the internal link 1 of the chain: the articulation pin 3 can instead rotate in the external holes 14 of the external link, which can be more easily lubricated. (A man skilled in the art immediately understands that the pin 3 could also be locked in the external holes 14, 14 and freely rotate with respect to the "internal" hole 18 of the internal link 1, even if this solution is much less advantageous since the lubricating grease would reach the "internal" hole 18 with more difficulty).

    [0022] In order to definitively clarify the difference with the prior art, the section A-A shown in Fig. 1c shows the minimum thickness "t" of the upper wall of the external link (measured at the highest point of the concavity 12 in Fig. 2a). Of course, a man skilled in the art immediately understands that such thickness "t" is equal to the (constant) thickness of the upper wall of a conventional external link.

    [0023] For completeness of description, it should be observed that on each side, the internal link 1 has for example a (conventional) relief 19.

    [0024] The second embodiment of the invention (remaining figures) essentially corresponds with the first embodiment of the invention, but with the difference that the external link is no longer single-piece, but rather formed by two modular parts.

    [0025] With reference to Fig. 3, the external link, indicated herein by the number 102, is formed by two modular parts, 102a (front part, or first part) and 102b (rear part, or second part), respectively. Fig. 6 corresponds with various views of the front part 102a while Fig. 7 corresponds with various views of the rear part 102b of the external link 102 of the second embodiment of the invention.

    [0026] It is inferred from Fig. 6 and from Fig. 3 that the front part 102a forms a thin wall/plate with overall uniform thickness (not considering the various openings that will be described hereinbelow). This is not valid for the rear part 102b, which forms a plate with non-uniform thickness, superimposable (and geometrically congruent with) on the front part 102a.

    [0027] The fact of having the above-illustrated external link 2 "divided in two parts" 102a and 102b offers the advantage of being able to use a pin 103 that can never been unthreaded (see Fig. 4d) since it has a central part 117 with greater diameter than the diameter of the two ends 103a, 103b thereof. It follows that in this second embodiment of the invention, in order to prevent a possible unthreading of the articulation pin 103 from the (central) hole 118 of the internal link 101 and from the two opposite (lateral) holes 114 of the external link 102, aligned with each other, the hole 118 must have a diameter slightly greater than that of the holes 114 in a manner so as to create a small step of abutment of the pin 103 against the internal side (opposite the external side 111, 111') of the walls of the external link 102. Otherwise, there are no substantial differences with respect to the first embodiment of the invention. It should be noted that the parts of the links of this second embodiment, corresponding with those of the first embodiment, were indicated with reference numbers increased by 100.

    [0028] In more detail, Fig. 6a shows the visible external side 111 of the front part 102a, Fig. 6c shows the non-visible internal side of the front part 102a, and finally Fig. 6b is the section A-A (Fig. 6a) of the front part 102a.

    [0029] Fig. 7a shows the non-visible internal side (see Fig. 3) of the rear part 102b, Fig. 7c shows the visible external side 111' of the rear part 102b, Fig. 7b is the front view (direction of the arrow P, Fig. 7a) of the rear part 102b, while Fig. 7d is the respective plan view.

    [0030] Fig. 8 shows the internal link of the present invention, indicated with 1 or 101, respectively, and it does not require particular elucidations in addition to that provided above.

    [0031] With reference to Figs. 3, 4, 5, 6 and 7, relative to the second embodiment, and in particular to Fig. 3a, it is observed that on the central portion 108 and on the two projections (barriers against impurities) 109, the rear part 102b of the external link 102 has a constant thickness, greater than the thickness of the remaining flat part 120 of the rear part 102b. Of course, when the parts 102a and 102b are assembled (see Fig. 3b), the plane defined by 108 and 109 abuts against the non-visible internal side 121 (see Fig. 6c) of the front part 102a. There is thus a structure for the external link 102 that is completely analogous (after the assembly of the parts 102a, b) to that described above for the external link 2 of the first embodiment, i.e. with concavities 112 (Fig. 3a) having a progression similar to that of the concavities 12 of the first embodiment. Thus, with regard to the obstruction (labyrinth) effect against the entrance of impurities in the external link 102, nothing has changed with respect to the first embodiment of the invention.

    [0032] In order to fasten the parts 102a,b together in a stable manner, some fixing means are of course provided. Such fixing means are for example three screws 122 with flared head inserted in the flared holes 123 of the front part 102a which are aligned with the threaded holes 124 of the rear part 102b of the external link 102 (see Figs. 3a, 4 and 7a). In order to facilitate the assembly, pairs of holes 125 and 126 are provided for inserting reference pins (already known in the art and not shown in the drawings), which serve to give precision to the system.

    [0033] In order to prevent an even minimal entrance of impurities, a quantity of grease could be inserted in the above-illustrated labyrinth interspace, before using the chain.


    Claims

    1. Cutting chain for chain saw machines for cutting ornamental stones, comprising internal links (1; 101) and external links (2; 102) that are alternated and connected to each other by means of articulation pins (3; 103), characterized in that each internal link (1; 101) has two ends (5, 5'; 105, 105') with substantially curved shape, a lower side (6) and an upper side having a recess (4), and in that each external link (2; 102) has, on an internal side of an upper wall thereof bearing the cutting inserts, a pair of concavities (12, 12; 112, 112) with curved progression similar to that of said ends (5, 5'; 105, 105'), such concavities (12, 12; 112, 112) terminating by forming respective projections (9, 9; 109, 109) on opposite ends of the external link (2; 102), such projections (9, 9; 109, 109) having the function of barrier against the entrance of impurities and cooperating with said concavities (12, 12; 112, 112) in order to form a labyrinth path with minimum interspace between an internal link and a concavity during the operation of the chain, in all the relative rotation positions (ϕ) between an internal link (1; 101) and an external link (2; 102); and in that said recess (4) receives said projections (9. 9; 109, 109) during the operation of the chain.
     
    2. Cutting chain according to claim 1, characterized in that said minimum interspace has a substantially constant thickness along an entire concavity (12, 12; 112, 112).
     
    3. Cutting chain according to claim 1 or 2, characterized in that said recess (4) is extended in a continuous and rectilinear manner between said ends (5, 5'; 105, 105') of an internal link (1; 101).
     
    4. Cutting chain according to any one of the preceding claims, characterized in that grease is inserted in said interspace in order to further prevent the even minimal entrance of impurities.
     
    5. Cutting chain according to any one of the preceding claims, characterized in that the external links (2) are obtained in a single piece.
     
    6. Cutting chain according to any one of the preceding claims 1 to 4, characterized in that the external links (102) are each formed by two modular and superimposable parts (102a; 102b), comprising a front part (102a) and a rear part (102b).
     
    7. Cutting chain according to claim 5, characterized in that the articulation pins (3) are locked in respective holes (18) of the internal links (2), the pins are cylindrical and have an intermediate part (17) with knurled surface as well as two lateral external ends (3a, 3b) with smooth surface.
     
    8. Cutting chain according to claim 6, characterized in that the articulation pins (103) are locked in respective holes (118) of the internal links (101), the pins are substantially cylindrical but have an intermediate part (117) with diameter slightly greater than the diameter of the two lateral external ends (103a, 103b) with smooth surface of the pin (103); and in that the diameters of the holes (114) of the external links (102), which receive said two lateral external ends (103a, 103b) with smooth surface of the pin (103), are slightly smaller than the diameter of a respective hole (118) of the internal link (101).
     
    9. Cutting chain according to claim 6, characterized in that the front part (102a) of the external link (102) forms a plate with constant thickness if the openings for introducing the fixing means (such as screws or the like) (122) are excluded, such fixing means serving to lock said two modular and superimposable parts (102a; 102b) together and keep them joined.
     


    Ansprüche

    1. Schneidkette für Kettensägemaschinen zum Schneiden von Ziersteinen, die innere Verbindungen (1; 101) und externe Verbindungen (2; 102) aufweist, die abgewechselt und mittels Gelenkpins (3; 103) miteinander verbunden sind, dadurch gekennzeichnet, dass jede innere Verbindung (1; 101) zwei Enden (5, 5'; 105, 105') mit einer im Wesentlichen gekrümmten Form, eine Unterseite (6) und eine Oberseite mit einem Einschnitt (4) aufweist, und dadurch, dass jede externe Verbindung (2; 102) auf einer inneren Seite einer oberen Wand hiervon, die die Schneideinsätze trägt, ein Paar von Konkavitäten (12, 12; 112, 112) mit gekrümmtem Verlauf ähnlich dem der genannten Enden (5, 5'; 105, 105'), wobei derartige Konkavitäten (12, 12; 112, 112) auslaufen, indem sie an entgegengesetzten Enden der externen Verbindung (2; 102) entsprechende Vorsprünge (9, 9; 109, 109) bilden, wobei derartige Vorsprünge (9, 9; 109, 109) die Funktion einer Barriere gegen das Eindringen von Verschmutzungen aufweisen und mit den genannten Konkavitäten (12, 12; 112, 112) zusammenwirken, um während des Betriebs der Kette in all den Relativpositionen (ϕ) zwischen einer inneren Verbindung (1; 101) und einer externen Verbindung (2; 102) ein Labyrinth mit minimalem Zwischenraum zwischen einer inneren Verbindung und einer Konkavität zu bilden; und dadurch, dass der genannte Einschnitt (4) die genannten Vorsprünge (9, 9; 109, 109) während des Betriebs der Kette aufnimmt.
     
    2. Schneidkette gemäß Anspruch 1, dadurch gekennzeichnet, dass der genannte minimale Zwischenraum entlang einer gesamten Konkavität (12, 12; 112, 112) eine im Wesentlichen konstante Dicke aufweist.
     
    3. Schneidkette gemäß Anspruch 1 oder 2, dadurch gekennzeichnet, dass sich der genannte Einschnitt (4) auf eine durchgehende und geradlinige Weise zwischen den genannten Enden (5, 5'; 105, 105') einer inneren Verbindung (1; 101) erstreckt.
     
    4. Schneidkette gemäß einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass in den genannten Einschnitt (4) Schmierfett eingebracht ist, um weiterhin die selbst minimale Aufnahme von Verunreinigungen zu verhindern.
     
    5. Schneidkette gemäß einem der vorangehenden Ansprüche, dadurch gekennzeichnet, dass die externen Verbindungen (2) in einem Stück gebildet sind.
     
    6. Schneidkette gemäß einem der vorangehenden Ansprüche 1 bis 4, dadurch gekennzeichnet, dass jede der externen Verbindungen (102) durch zwei modulare und übereinander lagerbare Teile (102a; 102b), die einen Vorderteil (102a) und einen Hinterteil (102b) aufweisen, gebildet sind.
     
    7. Schneidkette gemäß Anspruch 5, dadurch gekennzeichnet, dass die Gelenkpins (3) in entsprechenden Löchern (18) der inneren Verbindungen (2) arretiert sind, wobei die Pins zylindrisch sind und einen zwischenliegenden Teil (17) mit geriffelter Oberfläche sowie zwei laterale externe Enden (3a, 3b) mit glatter Oberfläche aufweisen.
     
    8. Schneidkette gemäß Anspruch 6, dadurch gekennzeichnet, dass die Gelenkpins (103) in entsprechenden Löchern (118) der inneren Verbindungen (101) arretiert sind, wobei die Pins zylindrisch sind aber einen zwischenliegenden Teil (117) mit einem Durchmesser, der geringfügig größer als der Durchmesser der zwei lateralen Enden (103a, 103b) mit einer glatten Oberfläche des Pins (103) aufweisen; und dadurch, dass die Durchmesser der Löcher (114) der externen Verbindungen (102), die die beiden genannten externen Enden (103a, 103b) mit glatter Oberfläche des Pins (103) aufnehmen, geringfügig geringer als der Durchmesser eines entsprechenden Lochs (118) der inneren Verbindung (101) sind.
     
    9. Schneidkette gemäß Anspruch 6, dadurch gekennzeichnet, dass der Vorderteil (102a) der externen Verbindung (102) eine Platte mit konstanter Dicke bildet, wenn die Öffnungen zum Einbringen des Befestigungsmittels (wie beispielsweise Schrauben oder dergleichen) (122) ausgenommen werden, wobei ein derartiges Befestigungsmittel dazu dient, die beiden genannten modularen und übereinander lagerbaren Teile (102a: 102b) miteinander zu arretieren und sie verbunden zu lassen.
     


    Revendications

    1. Chaîne coupante pour des machines à scier à chaîne pour couper des pierres d'ornement, comprenant des maillons internes (1 ; 101) et des maillons externes (2 ; 102) qui sont disposés en alternance et qui sont reliés entre eux à l'aide de broches d'articulation (3 ; 103), caractérisée en ce que chaque maillon interne (1 ; 101) a deux extrémités (5, 5' ; 105, 105') de forme globalement courbe, un côté inférieur (6) et un côté supérieur présentant un creux (4), et en ce que chaque maillon externe (2 ; 102) présente, sur un côté interne de sa paroi supérieure qui porte les plaquettes de coupe, une paire de concavités (12, 12 ; 112, 112) avec une progression courbe similaire à celle des extrémités (5, 5' ; 105, 105'), ces concavités (12, 12 ; 112, 112) se terminant par des saillies respectives (9, 9 ; 109, 109) sur les extrémités opposées du maillon externe (2 ; 102), ces saillies (9, 9 ; 109, 109) ayant une fonction de barrière contre l'entrée d'impuretés et coopérant avec les concavités (12, 12 ; 112, 112) afin de former un labyrinthe avec un espacement minimum entre un maillon interne et une concavité, pendant le fonctionnement de la chaîne, dans toutes les positions de rotation relatives (ϕ) entre un maillon interne (1 ; 101) et un maillon externe (2 ; 102) ; et en ce que le creux (4) reçoit les saillies (9, 9 ; 109, 109) pendant le fonctionnement de la chaîne.
     
    2. Chaîne coupante selon la revendication 1, caractérisée en ce que ledit espacement minimum présente une épaisseur globalement constante le long de toute une concavité (12, 12 ; 112, 112).
     
    3. Chaîne coupante selon la revendication 1 ou 2, caractérisée en ce que le creux (4) s'étend de manière continue et rectiligne entre les extrémités (5, 5' ; 105, 105') d'un maillon interne (1 ; 101).
     
    4. Chaîne coupante selon l'une quelconque des revendications précédentes, caractérisée en ce que de la graisse est introduite dans l'espacement afin d'empêcher encore plus l'entrée, même minimale, d'impuretés.
     
    5. Chaîne coupante selon l'une quelconque des revendications précédentes, caractérisée en ce que les maillons externes (2) sont obtenus d'une seule pièce.
     
    6. Chaîne coupante selon l'une quelconque des revendications 1 à 4 précédentes, caractérisée en ce que les maillons externes (102) sont formés chacun par deux parties (102a ; 102b) modulaires et superposables qui comprennent une partie avant (102a) et une partie arrière (102b).
     
    7. Chaîne coupante selon la revendication 5, caractérisée en ce que les broches d'articulation (3) sont bloquées dans des perçages respectifs (18) des maillons internes (2), les broches sont cylindriques et présentent une partie intermédiaire (17) à surface moletée, ainsi que deux extrémités externes latérales (3a, 3b) à surface lisse.
     
    8. Chaîne coupante selon la revendication 6, caractérisée en ce que les broches d'articulation (103) sont bloquées dans des perçages respectifs (118) des maillons internes (101), les broches sont globalement cylindriques mais présentent une partie intermédiaire (117) avec un diamètre légèrement plus grand que le diamètre des deux extrémités externes latérales (103a, 103b) à surface lisse de la broche (103) ; et en ce que les diamètres des perçages (114) des maillons externes (102) qui reçoivent les deux extrémités externes latérales (103a, 103b) à surface lisse de la broche (103) sont légèrement plus petits que le diamètre d'un perçage respectif (118) du maillon interne (101).
     
    9. Chaîne coupante selon la revendication 6, caractérisée en ce que la partie avant (102a) du maillon externe (102) forme une plaque à épaisseur constante, à l'exception des ouvertures pour l'introduction des moyens de fixation (tels que des vis ou autres) (122), ces moyens de fixation servant à bloquer ensemble les deux parties modulaires et superposables (102a ; 102b), et à les maintenir reliées.
     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



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    Patent documents cited in the description