EP0086703B1 - Device for automatic setting of assembling systems - Google Patents

Description

The present invention relates to devices for automatically fitting assembly systems such as screws, nuts, bolts, pinning staples, etc., and more particularly relates to their use on corresponding control machines, whether they are hand, screwdriver / unscrewer type, or automated or robotic type, in order to obtain a locking or unlocking of the assembly systems within these devices.

Such automatic laying devices must meet a first imperative which is to ensure the security of the precise installation of the assembly system on its site, which is represented by the hole (s) before receiving it. .

The machines currently known to the Applicant and which are fitted with such a device, are not entirely satisfactory due to the fact that the maintenance of the assembly system, most often provided by adhesion means, does not have the safety that can be provided by a mechanical locking mode ensuring a positive hold.

• Ainsi, le brevet des Etats-Unis d'Amérique No 3 331 268 enseigne un nez de vissage/dévissage pour agrafes comportant un moyen de verrouillage positif, mais la mise en oeuvre de ce dernier n'est pas automatique.

Some solutions have already been proposed in this direction to achieve the desired result:

• Thus, US Pat. No. 3,331,268 teaches a screwing / unscrewing nose for staples comprising a positive locking means, but the implementation of the latter is not automatic.

The non-automatic screwing / unscrewing nose concerned essentially comprises two coaxial elements, one of which, internal, ensures the rotational movement associated with screwing / unscrewing and the other, external, connected to a fixed element with limited angular movement, allows the actual positive locking of a clip inside the nose.

This locking, which is ensured manually in this patent, results from a limited rotary movement of the external element relative to the fixed element (30 ° in the case considered where the fingerprint configurations are hexagonal), said external element being adapted by its imprint to rotate the body of the assembly system with respect to an imprint formed on the fixed element and which penetrates into a groove of this body: the setting out of coincidence of the angles of the hexes of the external element and said body, and the imprint of the fixed element blocks this body inside the nose.

It follows from the above that the operation is not fully automatic since an operator is necessary to produce the rotational movement leading to the locking or unlocking of the assembly system on its laying device.

• - un élément de maintien en rotation (1A, 14) terminé en une extrémité par une empreinte (5,16) de section transversale non circulaire complémentaire dudit corps du système d'assemblage et adapté à s'atteler en rotation à ce corps,
• - un élément agrippant (4, 13) attelé axialement à l'élément de maintien et admettant, par rapport à celui-ci, un débattement angulaire prédéterminé entre deux positions extrêmes, terminé en une extrémité par une empreinte (3, 17) voisine axialement de l'empreinte de l'élément de maintien et adaptée à être franchie axialement par au moins une portion dudit corps, et de même section que cette dernière, ces deux empreintes étant en coïncidence en une seule des positions extrêmes, l'élément agrippant, dans l'autre des positions extrêmes, empêchant tout retrait de ladite portion,
• - un élément tournant (2, 11) adapté à être lié au moteur et un élément fixe (1, 12) adapté à être lié au boîtier, l'élément de maintien étant au moins imparfaitement et temporairement attelé en rotation, soit à l'élément fixe, soit à l'élément tournant, ce dispositif étant caractérisé en ce que, par rapport au document US 3 331 268 précité, il comporte en outre:
• - un ensemble d'entraînement en rotation (10, 20) interposé radialement entre les éléments tournants (2, 11) et agrippant, (4, 13) dont une portion (2a, 11a) liée à l'élément tournant est adaptée à entraîner par frottement une autre portion (8, 19) liée à l'élément agrippant, grâce à quoi, selon le sens de rotation de l'élément tournant, l'élément agrippant se décale angulairement par rapport à l'élément de maintien entre ses positions extrêmes, soit dans le sens du verrouillage, soit dans le sens du déverrouillage du système d'assemblage dans le dispositif de pose.

The present invention aims to provide a solution to this problem by making such an operation fully automatic and for this purpose proposes an automatic device for fitting assembly systems such as staples, screws or nuts, comprising a body of non-circular cross section. to be kept in rotation, intended to be mounted on a machine comprising a rotary drive motor disposed in a housing, of the type comprising, mounted coaxially:

• a rotational holding element (1A, 14) terminated at one end by an imprint (5.16) of non-circular cross section complementary to said body of the assembly system and adapted to be coupled in rotation to this body,
• - a gripping element (4, 13) axially coupled to the retaining element and admitting, relative to the latter, a predetermined angular movement between two extreme positions, terminated at one end by an imprint (3, 17) axially adjacent of the imprint of the holding element and adapted to be crossed axially by at least a portion of said body, and of the same section as the latter, these two imprints being in coincidence in only one of the extreme positions, the gripping element, in the other extreme positions, preventing any withdrawal of said portion,
• - a rotating element (2, 11) adapted to be linked to the motor and a fixed element (1, 12) adapted to be linked to the housing, the holding element being at least imperfectly and temporarily coupled in rotation, that is to say fixed element, or to the rotating element, this device being characterized in that, with respect to the aforementioned document US 3,331,268, it further comprises:
• - a rotational drive assembly (10, 20) interposed radially between the rotating (2, 11) and gripping elements (4, 13) of which a portion (2a, 11a) linked to the rotating element is adapted to drive by friction another portion (8, 19) linked to the gripping element, whereby, according to the direction of rotation of the rotating element, the gripping element is angularly offset relative to the holding element between its positions extremes, either in the locking direction or in the unlocking direction of the assembly system in the installation device.

Thanks to a drive element according to the invention, a limited rotation between holding and gripping elements allowing the desired locking and / or unlocking occurs automatically during the screwing or unscrewing operations.

Note the simplicity of the present solution compared to the lessons, in particular, of patent application EP 0072713 of the Applicant (whose priority date is earlier than that of the present application but whose publication date is later) concerns, not the installation but the removal of assembly systems.

• la fig. 1 est une coupe schématique axiale d'un dispositif d'agrafage avec verrouillage selon l'art antérieur,
• la fig. 2 est une coupe schématique axiale montrant la conformation structurale d'un dispositif de pose de vis extrapolé à partir du dispositif schématique de la figure 1,
• la fig. 3 est une coupe schématique axiale montrant la conformation structurale d'un dispositif de pose de vis et écrou extrapolé à partir du dispositif de la figure 1,
• la fig. 4 est une coupe axiale d'un nez de vissage/dévissage selon l'invention pour pose automatique d'agrafes d'épinglage,
• la fig. 5 est une coupe radiale selon la ligne IV-IV de la figure 4; et
• la fig. 6 est une coupe axiale d'un nez de vissage/dévissage selon l'invention pour pose automatique de vis ou d'écrou.

The invention will in any case be well understood in the remainder of the text which will give, by way of nonlimiting example, in support of the appended drawings, the embodiments which are suitable for various types of assembly. In the drawings:

• fig. 1 is a schematic axial section of a stapling device with locking according to the prior art,
• fig. 2 is an axial schematic section showing the structural configuration of a device for laying screws, extrapolated from the schematic device of FIG. 1,
• fig. 3 is an axial schematic section showing the structural conformation of a device for installing a screw and nut extrapolated from the device in FIG. 1,
• fig. 4 is an axial section of a screwing / unscrewing nose according to the invention for automatic installation of pinning staples,
• fig. 5 is a radial section along the line IV-IV of FIG. 4; and
• fig. 6 is an axial section of a screwing / unscrewing nose according to the invention for automatic fitting of screws or nuts.

The prior art recalled in FIG. 1 relates to a screwing / unscrewing nose for a pinning clip of an assembly A1. The actual clip B1 has a hexagonal body axially traversed by a screw stapling mechanism activated by the tightening of a nut. The assembly is controlled by a machine C, generally pneumatic. The aim is first of all to produce the locking of the clip B1 by an external gripping element D coaxial with a rotating element E driven by the engine of the machine and connected to an element F fixed relative to the housing of the machine; said locking is effected by rotation of 30 ° of the element D relative to the element F holding the body of the clip. A reverse rotation movement of 30 ° produces the unlocking of the clip.

The prior art described in FIG. 1 can be extrapolated to the case of a screw assembly A2 according to FIG. 2 or to that of a bolted assembly A3 according to FIG. 3.

In the first case, the combination of the elements to be used in the laying device is then D-E for the screw 82 which has to be driven. ner in rotation, while in the second case it is D-F for the screw B2 and D-E for the nut B3 which must be driven in rotation relative to the screw B2.

In all cases, the machine C is able to carry out the sequences of rotation and axial displacement which are necessary for fitting the assembly systems, which sequences are not within the scope of the invention.

In accordance with the prior art described above, it is obvious to note that the limited rotation of the external element D relative to either the fixed element F or the rotating element E, must always be carried out by hand since no automatic mode was taught by this prior art.

The invention therefore proposes, in the following description, an automatic mode of fitting and locking / unlocking which can be applied in the three assembly cases mentioned above and for various machines such as for example machines held by hand or machines of the automated or robotic type.

This automatic mode is obtained by a fourth drive element linked in rotation to the gripping element and which cooperates with the rotating element to allow the rotation of said gripping element, thus ensuring locking.

According to Figure 4, which relates to a device for applying a pinning clip, not shown, of known type, the fixed element 1, is terminated by a holding portion 1A, intended to receive the body of the clip in a hexagonal imprint 5, is linked to the housing of a control machine 7, and the rotating element 2, intended to receive the nut of said clip in favor of a hexagonal imprint 6, adapted to be driven in rotation by the engine of the machine (not shown), carries a radial boss 2a which is one of the components of the drive element identified 10 as a whole.

The gripping element 4 external to the elements 1 and 2, carries at its end a hexagonal imprint 3 identical to the imprint 5 and axially adjacent thereto.

The aforementioned elements 1, 2 and 4 are, on the whole, of known type and, not forming the essential part of the invention, will not be detailed here further.

The drive element 10, the details of which can be seen more clearly in FIG. 5, is completed by a flexible annular part 8, such as neoprene, bearing on the one hand radial and axial tongues 8a, 8b, the number of two in the example shown, and on the other hand threaded bulges to receive taper screws 9a, 9b whose heads are housed, on the one hand, in cylindrical radial housings of the element 4 and, on the other hand , in circumferential radial openings 1a, 1b with a preferred amplitude of 30 ° formed in the fixed element 1.

It is easy to note that during an initial screwing action (according to arrow F) exerted by the motor on the rotating element 2, the boss 2a will act on the tongues 8a, 8b to drive them and, by intermediate of the screws 9a and 9b securing in rotation the elements 8 and 4, place the element 4 in the relative position with respect to the element 1 which is shown in FIG. 5. The elasticity of the tongues 8a, 8b is such that they can be driven by the boss 2a, possibly in several turns, until the stop of the screws 9 against the edges of the openings 1a, 1b, then, by deformation and / or recoil, be crossed by said boss , and that, in any sense.

In this way, the clip can be introduced since then, the hexes of the imprints 5 and 3. are aligned (or coincidentally).

A reverse unscrewing movement (according to arrow F ′ in FIG. 5) will cause the tongues 8a and 8b which will act in rotation, by means of the screws 9a and 9b, the element 4 with respect to the 'fixed element 1 and thus lock the clip since the impression 3 then rotates by 30 ° relative to 5 then placing the sides in non-coincidence (opposition of the hexagonal shapes).

This amplitude of 30 °, preferred in the case of hexagonal imprints, corresponds to half the angles between the faces of said imprints. More generally, the preferred angle of rotation is that which allows the shape of the head to be brought into opposition with respect to itself.

The locked clip can then be placed through the hole of the assembly to be produced and then be tightened there by screwing the nut, driven in rotation although kept axially fixed by element 2, with respect to the mechanism staple which thus slides in the staple body held by the fixed element 1. There is an unlocking of the staple.

At the end of screwing the clip, the nose is no longer locked on the clip can be easily removed and introduced on the next and so on.

It is noted that the operation is entirely automatic since the actions in screwing or unscrewing correlatively produce the unlocking or locking of the clip which is the very objective of the invention.

According to FIG. 6, which applies to conventional bolts (hexagon) but which can be adapted to any other form of bolt head, in particular polygonal, which can be brought into opposition with respect to imprints of same shape by rotation of a determined angle, the process must be modified and adapted since the screw and / or the nut is only engaged with two elements, and moreover, in certain cases, the action in rotation on the screw (or nut) is suppressed while the locking action is still necessary.

As in the above description, the fixed element 12 is linked to the machine housing 21 (in a known manner) and the rotating element 11, driven by a motor (not shown), provided in the machine, carries a radial boss 11 a which is one of the components of the drive element marked 20 as a whole.

In the example shown, the gripping element 13 carries a hexagonal imprint 17 at its end, identical to the imprint 16 of an element 14 for holding the screw (or nut).

This element 14 carries, on the one hand, axial dog teeth 14a1 and 14a2 and, on the other hand, at least one ball screw 22a 22a and spring 22b whose external part is housed inside a slot preferably circumferential radial 13a of 30 °, practiced in element 13.

These dog teeth are located opposite other axial teeth 11 b1 and 11 b2 secured to the rotating element 11.

A first spring 15 disposed axially in an axial recess of the element 11 against a complementary stud integral with the element 14, tends to maintain the axial separation of the dogs 14a and 11b and a second spring 18 of stiffness lower than that of the spring 15 pushes the part 13 (which contains the part 14) into abutment, provided with a shoulder 13b, against a transverse shoulder 12a of the fixed element 12.

Finally, the drive element 20 is completed by a flexible part 19, similar to the part 8, carrying radial and axial tabs 19a, 19b, and its fixing to the element 13 is ensured by screws 23 of any type. known, not detailed here.

By analogy with the previous example, an unscrewing action exerted by the motor along F (which may be brief) drives the rotating element 11 which drives the element 13 to its hole thanks to the screws 23. The latter then rotates by 30 ° with respect to 14 which is slowed down by the presence of friction resulting from the support of the ball 22a on the fixed element 12. The same comments as above are to be made as to the chosen value of 30 °.

The hexes of the elements 13 and 14 being in coincidence, a screw head (or a nut) not shown can be introduced into the cavities 17 and 16.

The screwing action (according to the arrow f ⁱ ) produces the locking by the fact that 11 then drives 13 which rotates 30 ° relative to 14 still braked as a result of friction resulting from the pressure of the ball 22a on 12. A once this 30 ° offset has been obtained, the element 14 can, if necessary, be rotated in turn.

The elasticity of the tongues 19a and 19b is such that they can be driven by the boss 11a, possibly in several turns, until the circumferential stop of the screw 22 against one of the edges of the light 13a, without however being able to transmit at element 13 the entire driving torque of element 11. Element 13 rotates less quickly than the latter.

The screwing action via 13 continues until the moment, by pushing the device towards the assembly to be produced, the dog clutch teeth are brought into the rotational drive configuration.

This dog clutching action due to the simultaneous axial recoil of the elements 14 and 13 in the fixed element 12 is accompanied by the unlocking by the fact that the positive, direct drive of 14 by 11 is greater than the friction drive of 13 resulting from the action of the boss 11a on the tongues 19a and 19b. It is then the element 13 which moves back 30 ° relative to the element 14.

In other words, the angular displacement producing the unlocking appears when the dogs come into action although the machine always remains in the screwing position. Unlocking is thus obtained either by unscrewing, or by screwing and clutching.

The axial relaxation after stopping at the screwing therefore allows the evacuation of the laying nose in the unlocked position which allows the introduction of a new screw or nut then the restarting of a new laying cycle.

Of course, when the screw must remain stationary, only locking or unlocking pulses are necessary. The system described in Figure 4 where the fixed element 1 would have a blind footprint 5 would give the expected results, the rotation of the rotating element 2 having only the object of ensuring the opera locking / unlocking. It is of course possible to simultaneously rotate the screw and nut, but in the opposite direction.

Furthermore, the devices shown are adapted to a hexagonal conformation; but any other conformation (non-circular) allowing to be put in opposition with itself by rotation of a determined angle could just as well be appropriate (square, triangle, oval, etc.).

Finally, the friction drive systems transmitting a torque from the rotating element to the gripping element, described as being formed from a flexible piece with tongues, could be of a completely different design, just as could be different. friction system with ball and spring between fixed element and holding element, insofar as the results obtained above would be the same. In addition, the number of bosses is arbitrary.

It should be noted that the spring 18 which just performs a holding role can possibly be omitted.

Claims (10)

1. A device for automatic setting of assembling systems such as clamp pins, screws or nuts comprising a body of noncircular cross-section to be maintained into rotation, intended to be mounted to a machine comprising a driving motor for rotation disposed in a housing and of the type comprising, mounted coaxially:

- a rotation holding member (1A, 14) terminated at one end by a socket (5, 16) of non circular cross-section complementary to said assembly system body and intended to rotatably engage such body,

- a gripping member (4, 14) axially connected to the holding member and admitting a predetermined angular displacement in respect to the latter between two extreme positions, and terminated at one end by a socket (3, 17) axially adjacent to the socket of the holding member and adapted to be axially passed through by at least a portion of said body and having the same cross-section as the latter, both of these sockets coinciding at a single one of the extreme positions, with the gripping member preventing, in the other extreme position, any retracting of said portion,

- a rotary member (2, 11) adapted to be connected to the motor and a stationary member (1, 12) adapted to be connected to the housing, with the holding member being at least imperfectly and temporarily rotatably connected either to the stationary member or to the rotary member, such device being characterized in that it also comprises:

- a driving assembly for rotation (10,20) radially interposed between the rotary (2, 11) and gripping members (4,13), a portion (2a, 11 a) of which connected to the rotary member is adapted to frictionally drive another portion (8, 19) connected to the gripping member, whereby, depending on the direction of rotation of the rotary member, the gripping member is angularly offset relative to the holding member between its extreme positions, either in the direction of locking or in the direction of unlocking of the assembly system in the mounting device.

2. A device according to claim 1, characterized in that the sockets (3, 5, 16, 17) have a polygonal shape and in that the extreme positions respectively correspond to the bringing into coincidence and into opposition of the sockets one relative to the other.

3. A device according to claim 2, characterized in that the sockets are hexagonal and in that the angular relative offsetting between the gripping member (4,13) and maintaining member (1,14) is 30°.

4. A device according to claim 1, characterized in that the driving member (10, 20) is formed of a radial boss (2a, 11 a) made integral with the rotary element and of a supple member (8,19) connected to the gripping member (4,13) presenting supple tongues (8a, 8b, 19a, 19b) thereon for frictionally cooperating in rotation with said boss.

5. A device according to any one of claims 1 to 4, for automatic setting of clamp pins comprising a body and a mechanism sliding through said body by screwing/unscrewing a nut on said mechanism, characterized in that the holding member (1A) and the stationary member (1) are made integral with one another while the rotary member (2) comprises a socket (6) for receiving said nut.

6. A device according to any one of claims 1 to 5, characterized in that the relative limited angular displacement between the holding member (1A, 14) and gripping member (4, 13) is ensured by a radially projecting member (9a, 9b, 22) made integral with one of the members (4,14) penetrating into a circumferential opening (1 a, 1b, 13a) formed in the other member.

7. A device according to claim 4, characterized in that the stationary member (1) is made integral with the holding member (1A) and in that the supple member (8) is connected to the gripping member (4) by means of screws (9a, 9b) passing through said stationary member (1) through circumferential openings (1a, 1b).

8. A device according to any one of claims 1 to 4, for mounting screws and nuts, characterized in that the holding member (14) and the rotary member (11) carry complementary axial clutch means (11 b, 14a), in that the holding member also comprises a radial frictional element (22) on the stationary member (12) passing through the gripping member (13), with the holding member (14) admitting an axial displacement in respect to member (11) between a separation configuration in which they are elastically maintained and a joining configuration in which the clutch means cooperate and, the direction of rotation of the rotary member (11) being maintained, the gripping member changes the extreme position in respect to the holding member.

9. A device according to claim 8, characterized in that the radial friction member between the holding member and the stationary member is formed by a screw (22) with a ball therein disposed in the holding member and the ball (22a) of which is urged by a spring (22) towards the stationary member.

10. A device according to any one of claims 1 to 4, for holding a nut, characterized in that the holding member and the stationary member are made integral with one another.

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