LIFTGATE LATCH

Description

[0001] This invention relates to latches for securing the position of a door according to the preamble of claim 1.

[0002] A typical vehicle door includes a latch which defines three modes of operation. A first mode is a latched mode in which a striker forkbolt is engaged to a striker. A second mode of operation is an open mode of operation in which the striker forkbolt and striker are released and function independently to provide access to a vehicle. A third mode of operation is one in which the striker forkbolt and striker are partially engaged allowing limited motion of a door which has been partially closed or which has been released incompletely from a latched condition to a mode of operation referred to as safety or secondary mode. The sequence of opening a vehicle door in which the door is rotatable about a horizontally oriented axis such as a deck lid includes a first step of releasing the vehicle door from a latched mode of operation, whereupon a weatherstrip imparts a force against the door causing an upwardly directing motion thereof. Upon reaching the limit of such displacement, the door returns to a position resting against the weatherstrip, and in some situations, engaging the striker forkbolt and striker sufficiently to reach a safety mode of operation. A vehicle operator inside such a vehicle attempting to open the door will find the door in a safety mode of operation, and consequently impossible to open.

[0003] GB-A-2 155 535 discloses a latch according to the preamble of claim 1 for a vehicle door which offers a sequence of operations in which the door is first released from a latched condition to an ajar condition in which no safety mode of operation is available. Subsequent to the ajar condition the vehicle door may then pass to an open position in which the safety mode of operation is reset and may be utilized upon subsequent attempts to close the door. The latch comprises several levers which may contact each other to swivel latches in order to change the mode of operation.

[0004] From their swivelled position the levers have to pivot back in their initial position due to the force of gravity. If. the door is, however, slammed, it has the tendency to spring back in an open position. The levers, however, are due to their inertia mass not able to lock the door in a latched condition so that the door is allowed to rebound in the open position. Therefore, the door equipped with the known latch must always be closed slowly.

[0005] Object of the present invention is to provide for a latch which ensures a safe closure of the door.

[0006] This object is achieved by the features of claim 1.

[0007] The present invention includes a device which establishes a sequence for the modes of operation of a door. The sequence is latched, ajar, open and safety. The modes of operation are achieved by the interaction of a striker and a striker forkbolt. The striker forkbolt is secured to the liftgate and the striker is secured to the fixed structure. The striker forkbolt is rotatable about a first axis to various predetermined angular positions. The striker forkbolt may be restricted to various rotational positions to accomplish one of the four modes of operation. A first angular restriction of the striker forkbolt in which the striker forkbolt is engaged with a striker defines the latched mode of operation. A second angular restriction allows unrestricted rotation of the striker catch between the first limit of rotation and a maximum limit of rotation in which the striker forkbolt and the striker may be disengaged upon application of a force attempting to displace the liftgate to an ajar position. A third range of angular positions of the striker catch occurs upon rotation of the striker forkbolt to the maximum limit of rotation whereupon the striker forkbolt and the striker are completely disengaged permitting the door to be positioned in an open mode of operation. The fourth range of angular positions occurs in which the striker forkbolt is restricted to a second limit of rotation in which the striker forkbolt engages the striker defining a safety mode of operation. The invention includes a pawl which is selectively rotatable about a second axis and may be engaged with cooperating abutment surfaces defined on the striker forkbolt to provide various rotational restrictions thereof. The pawl is maintained in a first position engaging a first radially extending abutment surface to define the latched condition. The pawl is maintained in a second angularly displaced position which prevents the pawl from engaging the striker forkbolt to define an ajar mode of operation in which the striker forkbolt is free to rotate from the latched condition to a maximum limit of rotation. The pawl is maintained in a third condition in which the pawl is compliantly urged into contact with the rotatable striker forkbolt to define an open mode of operation. Finally, the pawl is maintained in a fourth condition engaged with a second cooperating radially extending abutment surface of the striker forkbolt to define a safety mode of operation. The preferred embodiment of the present invention includes a first rotatable member engaged with the pawl drivingly engaged to a second member. The second member may be selectively restricted in rotation by an engagement with a third member. Such a restriction of rotation of the second member thereby restricts rotation of the first member defining a displaced position of the pawl which permits the vehicle door to be operated in an ajar condition in which the door will not enter the safety mode of operation until it has been displaced into the position defined by the open mode of operation.

[0008] These and other details of the present invention will become more readily apparent by reference to the following detailed description of the embodiments as shown in the drawings.

Figure 1 is a perspective view of a structure including a door which is controlled by the apparatus of the present invention;

Figure 2 is a plan view of a first plane of the components of the present invention illustrating the latched mode of operation;

Figure 3 is a plan view of a first plane of the components of the present invention illustrating an ajar mode of operation;

Figure 4 is a plan view of the second plane of the components of the present invention illustrating the latched mode of operation;

Figure 5 is a plan view of the second plane of the components of the present invention illustrating the end of ajar mode of operation just before reaching the open position;

Figure 6 is an explosive view of the apparatus according to the present invention.

[0009] The present invention comprises an apparatus for establishing a mode of operation of a vehicle door 10 as shown in Figure 1, secured to the fixed structure of an automobile 14 having striker assembly 16 engageable with the apparatus of the present invention 18. The apparatus of the present invention is secured to the vehicle door 10 and is utilized to define and establish various modes of operation of vehicle door 10. The apparatus of the present invention constitutes an assembly of components which may be viewed in various perspectives and for purposes of simplified description will be discussed as viewed in two planes. A first plane of operation may be viewed in Figures 2 and 3 including a striker forkbolt 20 rotatable about a first axis 22. In addition, striker loop 24 is shown engaged to striker forkbolt 20. A pawl 26 rotatable about a second axis 28 includes a radially extending member 30 shown engaged with a cooperating abutment surface 32, thereby defining a restriction of rotation of striker forkbolt 20. This completes the description of the positional inter-relationship of pawl 26 and striker forkbolt 20, defining a latched mode of operation. Figure 3 illustrates the positional inter-relationship of striker forkbolt 20 and pawl 26 to define an ajar mode of operation. As is illustrated, the radially extending member 30 is rotatably displaced to a position which provides no restriction of rotation of striker forkbolt 20. Figures 2, 3, 4 and 5 provide views of the first and second planes of the present invention, illustrating the mechanism which establishes the position of pawl 26 including release lever 34 which is rotatably engaged with pawl 26. Release lever 34 is drivingly engaged with actuator lever 36 which is rotatably secured about third axis 38. A release lever holder 40 is rotatably fixed about fourth axis 42 and defines an abutment surface 44 engageable with cooperating surface 46 of actuator lever 36 to define the ajar mode of operation shown in Figure 3. As previously illustrated in Figure 3, in the ajar mode of operation, pawl 26 is maintained in a position of rotation free from any engagement with striker forkbolt 20 providing unrestricted rotation between a latched mode of operation as shown in Figures 2 and 4 and a maximum limit of rotation of striker forkbolt 20 almost reached in Figure 5. As shown in Figures 4 to 6, release lever holder 40 includes a cam-follower portion 50 which follows a cam profile 51 defined substantially by radius R1 and R2 defined on striker forkbolt 20. Upon rotation of striker forkbolt 20 to an open position cam-follower 50 is displaced laterally by a dimension equal to R2 minus R1 thereby releasing abutment surface 44 from cooperating abutment surface 46 permitting actuator lever 36, release lever 34, and pawl 26 to be compliantly urged by a spring into contact with cooperating abutment surface 32 of radially extending surface 54 of striker forkbolt 20, therein defining an open mode of operation. A final mode of operation is defined by the consequence of incomplete closure of door 10, whereupon striker forkbolt 20 engaged with striker loop 24 is partially rotated about first axis 22 such that radially extending member 30 engages with a cooperating abutment surface 32 defined on striker forkbolt 20. The angular restriction of rotation defined by engagement of the respective structures establishes a relative range of rotation of pawl 26 and striker forkbolt 20 which is referred to as the safety mode of operation. Further closing force imposed upon door 10 causes further rotation of striker forkbolt 20 to accomplish the latched mode of operation illustrated in Figures 2 and 4. It may be noted that actuator lever 36 can be rotatably displaced from a latched mode of operation to an ajar mode of operation by an actuator establishing a selected position by electromotive force or manually operated cable 60.

[0010] Fig. 5 shows the configuration at the end of the ajar mode just before reaching the open position. The release lever 34 holds the pawl 26 away from the radially extending abutment surfaces 32, which have just passed beyond the nose of radially extending member 30. Fig. 5 shows an artificial transition stage just after the pawl 26 has cleared the safety mode abutment surface and where further rotation of the forkbolt 20 has in the meantime caused the release lever holder 40 to withdraw from its "hold" position for the ajar mode (at cam distance R₂), permitting the pawl 26 to rest its radially extending member 30 on cooperating abutment surface 32 of forkbolt 20.

Claims

1. A lock apparatus for establishing different mode of operation when locking a door (10) by providing a range of positional interrelationships with respect to a fixed structure including a striker (24) secured to said fixed structure, which is selectively engageable with a striker forkbolt (20) secured to said door (10) and rotatable about a first axis (22), said apparatus comprising:

a striker forkbolt (20), which is selectively engageable with said striker, which is securable to said door (10) and which is rotatable about a first axis (22) to predetermined angular positions with respect to said striker (24);

means to selectively restrict the angle of rotation of said striker forkbolt (20) to accomplish four modes of operation;

a latched mode of operation in which said striker forkbolt (20) is engaged with said striker (24) and restricted from displacement;

an ajar mode of operation in which free rotation of the forkbolt from the latched position is allowed upon rotation of the forkbolt by the striker during unimpeded opening of the door to a maximum limit of rotation at which the striker loop has been liberated;

an open mode of operation which corresponds to said maximum limit of rotation of said striker-forkbolt (20); and

a safety mode of operation in which during subsequent closing upon passing a second limit of rotation reopening beyond said second limit is then blocked and in which a limited range of displacement between said door (10) and said fixed structure is allowed;

wherein said means to selectively restrict the angle of rotation of said striker forkbolt (20) comprises a pawl (26) selectably rotatable about a second axis (28) having a first radially extending portion (30) selectably engageable with first and second cooperating radially extending abutment surfaces defined on said striker forkbolt (20) to restrict rotation thereof;

wherein said pawl (26) is maintained in a first condition engaging said first radially extending abutment surface so as to retain said striker forkbolt (20) at a first limit of rotation thereby defining said latched mode of operation;

and wherein said pawl (26) is maintained in a second condition preventing said pawl (26) from engaging said striker forkbolt (20) to define said ajar mode of operation; said pawl (26) is maintained in a third condition to define said open mode of operation; and, said pawl (26) is maintained in a fourth condition engaged with said second cooperating radially extending abutment surface of said striker forkbolt (20) to define said safety mode of operation;

characterized by a first member (34) pivotally mounted on the second axis (28) in rotational engagement with said pawl (26) such that in the ajar mode of operation said first member (34) assumes a position rotated away from said striker forkbolt (20) so as to hold the pawl (26) in said second condition in which it is prevented from engagement with the striker forkbolt (20), whereas during said open mode of operation said pawl (26) is compliantly urged into engagement therewith.

2. The apparatus of claim 1 wherein said means to selectively restrict the angle of rotation of said striker-forkbolt (20) comprises:
   means for selectively restricting rotation of said first member (34) thereby defining said second condition of said pawl (26) in which said pawl (26) is prevented from engaging with said striker-forkbolt (20) to define said ajar mode of operation.

3. The apparatus of claim 2 wherein said means for selectively restricting rotation of said first member (34) comprises:

a second member (36) drivingly engaged to said first member (34); and

means for selectively restricting rotation of said second member (36) thereby defining said second condition of said pawl (26) in which said pawl (26) is prevented from engaging said striker forkbolt (20) to define said ajar mode of operation.

4. The apparatus of claim 2 wherein said means to selectively restrict the angle of rotation of said first member (34) comprises:

a second member (36) drivingly engaged to said first member (34); and

a third member (40) selectively engageable with cooperating abutment surfaces (46) defined on said second member (36) restricting rotation of said second member (36) upon engagement therewith and thereby defining said second condition of said pawl (26) in which said pawl (26) is prevented from engaging said striker forkbolt (20) to define said ajar mode of operation.

5. The apparatus of claim 1 wherein said pawl (26) is rotatably connected to a force actuator (60) defining a rotary position thereof including a first rotary position defining said latched mode of operation and a second rotary position defining said ajar mode of operation.

6. The apparatus of claim 4 wherein said third member (40) is disengaged from said cooperating abutment surface (46) defined on said second member (36) in response to a force applied thereto by an abutting surface (51) defined on said striker forkbolt (20) to establish said safety mode of operation.

Ansprüche

1. Schließmechanismus zum Herbeiführen unterschiedlicher Betriebsarten beim Schließen einer Tür (10), dadurch daß eine Reihe von Positionsbeziehungen in Bezug auf eine feste Struktur vorgesehen sind, die einen an der festen Struktur befestigten Anschlag (24) enthält, der wahlweise mit einem an der Tür (10) befestigten Anschlag-Gabelbolzen (20) in Eingriff gebracht werden kann, wobei der Gabelbolzen um eine erste Achse (22) drehbar ist und wobei der Mechanismus enthält:

einen Anschlag-Gabelbolzen (20), der wahlweise mit dem Anschlag in Eingriff gebracht werden kann, der an der Tür (10) befestigbar ist und der um eine erste Achse (22) in vorbestimmte Winkelpositionen in Bezug auf den Anschlag (24) gedreht werden kann;

Mittel zur wahlweisen Beschränkung des Drehwinkels des Anschlag-Gabelbolzens (20), um vier Betriebsarten zu schaffen;

eine verriegelte Betriebsart, in der der Anschlag-Gabelbolzen (20) in Eingriff mit dem Anschlag (24) ist und an einer Verschiebung gehindert ist;

eine angelehnte Betriebsart, in der eine freie Drehung des Gabelbolzens aus der verriegelten Stellung möglich ist, nach Drehung des Gabelbolzens durch den Anschlag während eines ungehinderten Öffnens der Tür bis zu einer Obergrenze der Drehung, bei der der Anschlagring freigegeben worden ist;

eine geöffnete Betriebsart, die der Obergrenze der Drehung des Anschlag-Gabelbolzens (20) entspricht; und

eine gesicherte Betriebsart, in der während des nachfolgenden Schließens nach dem Passieren einer zweiten Begrenzung der Drehung das erneute Öffnen über die zweite Begrenzung hinaus dann blockiert ist und in der eine begrenzte Verschiebung zwischen der Tür (10) und der festen Struktur möglich ist;

wobei die Mittel zur wahlweisen Beschränkung des Drehwinkels des Anschlag-Gabelbolzens (20) eine wahlweise um eine zweite Achse (28) drehbare Klinke (26) enthalten, die einen ersten sich radial erstreckenden Abschnitt (30) aufweist, der wahlweise mit ersten und zweiten zusammenwirkenden, sich radial erstreckenden Anlageflächen in Eingriff gebracht werden kann, die am Anschlag-Gabelbolzen (20) gebildet sind, um eine Drehung desselben zu beschränken;

wobei die Klinke (26) in einem ersten Zustand gehalten ist, in dem sie mit der ersten sich radial erstreckenden Anlagefläche in Eingriff ist, um den Anschlag-Gabelbolzen (20) an einer ersten Begrenzung der Drehung zu halten und so die verriegelte Betriebsart zu definieren;

und wobei die Klinke (26) in einem zweiten Zustand gehalten wird, in dem die Klinke (26) daran gehindert ist, mit dem Anschlag-Gabelbolzen (20) in Eingriff zu kommen, um die angelehnte Betriebsart zu definieren; die Klinke (26) wird in einem dritten Zustand gehalten, um die geöffnete Betriebsart zu definieren; und die Klinke (26) wird in einem vierten Zustand gehalten, in dem sie mit der zweiten zusammenwirkenden, sich radial erstreckenden Anlagefläche des Anschlag-Gabelbolzens (20) in Eingriff ist, um die gesicherte Betriebsart zu definieren;

gekennzeichnet durch ein erstes Bauteil (34), das drehbar an der zweiten Achse (28) angebracht und so in Dreheingriff mit der Klinke (26) ist, daß in der angelehnten Betriebsart das erste Bauteil (34) eine Stellung annimmt, in der es vom Anschlag-Gabelbolzen (20) weggedreht ist, um die Klinke (26) im zweiten Zustand zu halten, in dem sie am Eingriff mit dem Anschlag-Gabelbolzen (20) gehindert ist, wogegen während der geöffneten Betriebsart die Klinke (26) nachgebend in Eingriff mit ihm gedrängt wird.

2. Mechanismus nach Anspruch 1, bei welchem die Mittel zur wahlweisen Begrenzung des Drehwinkels des Anschlag-Gabelbolzens (20) enthalten:
Mittel zur wahlweisen Begrenzung der Drehung des ersten Bauteils (34), wodurch der zweite Zustand der Klinke (26) definiert wird, in dem die Klinke (26) am Eingriff mit dem Anschlag-Gabelbolzen (20) gehindert ist, um die angelehnte Betriebsart zu definieren.

3. Mechanismus nach Anspruch 2, bei welchem die Mittel zur wahlweisen Begrenzung der Drehung des ersten Bauteils (34) enthalten:

ein zweites Bauteil (36), das mit dem ersten Bauteil (34) in Triebschluß ist; und

Mittel zur wahlweisen Begrenzung der Drehung des zweiten Bauteils (36), wodurch der zweite Zustand der Klinke (26) definiert wird, in dem die Klinke (26) am Eingriff mit dem Anschlag-Gabelbolzen (20) gehindert ist, um die angelehnte Betriebsart zu definieren.

4. Mechanismus nach Anspruch 2, bei welchem die Mittel zur wahlweisen Beschränkung des Drehwinkels des ersten Bauteils (34) enthalten:

ein zweites Bauteil (36), das in Triebschluß mit dem ersten Bauteil (34) ist; und

ein drittes Bauteil (40), das wahlweise mit am zweiten Bauteil (36) gebildeten, zusammenwirkenden Anlageflächen (46) in Eingriff gebracht werden kann und das die Drehung des zweiten Bauteils (36) beschränkt, nachdem es mit diesem in Eingriff gekommen ist, und das dadurch den zweiten Zustand der Klinke (26) definiert, in dem die Klinke (26) am Eingriff mit dem Anschlag-Gabelbolzen (20) gehindert ist, um die angelehnte Betriebsart zu definieren.

5. Mechanismus nach Anspruch 1, bei welchem die Klinke (26) drehbar mit einem Kraftauslöser (60) verbunden ist, der deren Drehstellung bestimmt, einschließlich einer ersten Drehstellung, die die verriegelte Betriebsart definiert, und einer zweiten Drehstellung, die die angelehnte Betriebsart definiert.

6. Mechanismus nach Anspruch 4, bei welchem das dritte Bauteil (40) außer Eingriff mit der am zweiten Bauteil (36) gebildeten, zusammenwirkenden Anlagefläche (46) in Reaktion auf eine Kraft ist, die auf es über eine Anlagefläche (51) am Anschlag-Gabelbolzen (20) übertragen wird, um die gesicherte Betriebsart herbeizuführen.

Revendications

1. Appareil de verrouillage pour établir différents modes de fonctionnement lorsqu'on verrouille une porte (10), en procurant une gamme d'interrelations de positionnement par rapport à une structure fixe comprenant un taquet (24) fixé à ladite structure fixe, qui peut être sélectivement mis en prise avec un boulon à fourche (20) de taquet fixé à la dite porte (10) et susceptible de tourner autour d'un premier axe (22), ledit appareil comportant :

- un boulon à fourche (20) de taquet, qui peut être sélectivement mis en prise avec ledit taquet, qui peut être fixé à ladite porte (10) et qui est susceptible d'être entraîné en rotation autour d'un premier axe (22) jusqu'à des positions angulaires prédéterminées par rapport audit taquet (24) ;

- des moyens pour restreindre sélectivement l'angle de rotation dudit boulon à fourche (20) de taquet afin de fournir quatre modes de fonctionnement :

- un mode de fonctionnement verrouillé dans lequel ledit boulon à fourche (20) de taquet est en prise avec ledit taquet (24) et est empêché de se déplacer ;

- un mode de fonctionnement entrebâillé dans lequel la libre rotation dudit boulon à fourche est autorisée depuis la position verrouillée, lors de la mise en rotation dudit boulon à fourche par le taquet durant une ouverture sans entrave de la porte, jusqu'à la limite maximale de rotation dans laquelle la boucle du taquet a été libérée ;

- un mode de fonctionnement ouvert qui correspond à ladite limite maximale de rotation dudit boulon à fourche (20) de taquet ; et

- un mode de fonctionnement de sécurité dans lequel, au cours de la fermeture ultérieure, lors du passage par une deuxième limite de rotation, une réouverture au-delà de ladite deuxième limite est alors empêchée et dans lequel une plage limitée de déplacement est permise entre ladite porte (10) et ladite structure fixe ;

- lesdits moyens pour restreindre sélectivement l'angle de rotation dudit boulon à fourche (20) de taquet comprenant un cliquet (26) susceptible d'être entraîné en rotation sélectivement autour d'un deuxième axe (28), ayant une première partie (30) s'étendant radialement susceptible d'être mise en prise sélectivement avec des première et deuxième surfaces de butée coopérantes s'étendant radialement, formées sur ledit boulon à fourche (20) de taquet pour restreindre la rotation de celui-ci ;

- ledit cliquet (26) étant maintenu dans une première condition en prise avec ladite première surface de butée s'étendant radialement de façon à retenir ainsi ledit boulon à fourche (20) de taquet à une première limite de rotation, définissant ainsi le mode de fonctionnement verrouillé ;

- et ledit cliquet (26) étant maintenu dans une deuxième condition empêchant ledit cliquet (26) d'être mis en prise avec ledit boulon à fourche (20) de taquet pour définir ledit mode de fonctionnement entrebâillé ; ledit cliquet (26) étant maintenu dans une troisième condition pour définir ledit mode de fonctionnement ouvert ; et ledit cliquet (26) étant maintenu dans une quatrième condition en prise avec ladite deuxième surface de butée en coopération s'étendant radialement dudit boulon à fourche (20) de taquet pour définir ledit mode de fonctionnement de sécurité ;

- caractérisé par un premier organe (34) monté de façon pivotante sur le deuxième axe (28) dans un montage en rotation avec ledit cliquet (26), de telle sorte que, dans le mode de fonctionnement entrebâillé, ledit premier organe (34) prenne une position tournée éloignée dudit boulon à fourche (20) de taquet de façon à maintenir le cliquet (26) dans ladite deuxième condition dans laquelle il interdit l'engagement avec le boulon à fourche (20) de taquet, tandis que durant le mode de fonctionnement ouvert, ledit cliquet (26) est poussé de manière flexible en prise avec celui-ci.

2. Appareil selon la revendication 1, dans lequel lesdits moyens pour restreindre sélectivement l'angle de rotation dudit boulon à fourche (20) de taquet comportent :

- des moyens pour restreindre sélectivement la rotation dudit premier organe (34), en définissant ainsi ladite deuxième condition dudit cliquet (26) dans laquelle ledit cliquet (26) est empêché de venir en prise avec ledit boulon à fourche (20) de taquet, pour définir le mode de fonctionnement entrebâillé.

3. Appareil selon la revendication 2, dans lequel lesdits moyens pour restreindre sélectivement la rotation dudit premier organe (34) comportent :

- un deuxième organe (36) en prise d'entraînement avec ledit premier organe (34) ;

- des moyens pour restreindre sélectivement la rotation dudit deuxième organe (36), en définissant ainsi ladite deuxième condition dudit cliquet (26) dans laquelle ledit cliquet (26) est empêché de venir en prise avec ledit boulon à fourche (20) de taquet, pour définir ledit mode de fonctionnement entrebâillé.

4. Appareil selon la revendication 2, dans lequel lesdits moyens pour restreindre sélectivement l'angle de rotation dudit premier organe (34) comportent :

- un deuxième organe (36) en prise d'entraînement avec ledit premier organe (34) ; et

- un troisième organe (40) susceptible de venir sélectivement en prise avec des surfaces de butée coopérantes (46) formées sur ledit deuxième organe (36), restreignant la rotation dudit deuxième organe (36) lors de sa venue en prise avec celui-ci, et définissant ainsi ladite deuxième condition dudit cliquet (26) dans laquelle ledit cliquet (26) est empêché de venir en prise avec ledit boulon à fourche (20) de taquet, pour définir ledit mode de fonctionnement entrebâillé.

5. Appareil selon la revendication 1, dans lequel ledit cliquet (26) est connecté de façon rotative à un actionneur de force (60) définissant une position rotative de celui-ci, comprenant une première position rotative définissant ledit mode de fonctionnement verrouillé et une deuxième position rotative définissant ledit mode de fonctionnement entrebâillé.

6. Appareil selon la revendication 4, dans lequel ledit troisième organe (40) est désengagé de ladite surface de butée coopérante (46) formée sur ledit deuxième organe (36), en réponse à une force appliquée à celui-ci par une surface de butée (51) formée sur ledit boulon à fourche (20) de taquet, pour établir ledit mode de fonctionnement de sécurité.

Drawing