EP1772205B1 - Device for machining of pipes - Google Patents

Description

• un corps sur lequel est articulée une gâchette d'actionnement à mouvement alternatif et auquel est relié de façon mobile un organe supportant une tête de travail ;
• un dispositif d'entraînement de l'organe support monté sur le corps et relié à la gâchette d'actionnement ; l'organe support comprenant une crémaillère à grandes dents, le dispositif d'entraînement comprenant un premier pignon à grandes dents en prise avec la crémaillère, un cliquet d'entraînement et un cliquet de retenue, le cliquet d'entraînement assurant le mouvement d'avance, dans le sens souhaité, de la crémaillère, le cliquet de retenue empêchant le mouvement de recul, dans le sens inverse au sens souhaité, de la crémaillère permettant ainsi un mouvement d'avance progressif sous l'action d'un mouvement alternatif d'entraînement de la gâchette d'actionnement. Le document FR-A-2 626 505 décrit par exemple un tel outil sans ledit pignon en prise avec la crémaillère.

The invention relates to a tool for working tubes, of the type comprising:

• a body on which is articulated a reciprocating actuating trigger and to which is connected movably a member supporting a working head;
• a drive device of the support member mounted on the body and connected to the actuating trigger; the support member comprising a rack with large teeth, the driving device comprising a first pinion with large teeth engaged with the rack, a driving pawl and a retaining pawl, the driving pawl ensuring the movement of advance, in the desired direction, the rack, the retaining pawl preventing the recoil movement, in the opposite direction to the desired direction, the rack and allowing a progressive advance movement under the action of an alternating movement of drive trigger. The document FR-A-2 626 505 describes for example such a tool without said pinion engaged with the rack.

It is known, in the field of tube work, to use bending tools, shears for cutting, forceps or crimping tools rings on the ends of a tube.

The evolution of tube applications towards the use of polyethylene-aluminum-polyethylene multilayer materials and to larger and larger tube diameters, up to 32 mm, is leading manufacturers of apparatus for tube work. to develop devices requiring higher and higher efforts on the work head. Thus, when it comes to bending multilayer polyethylene-aluminum-polyethylene tubes, this operation requires the application of a high force (500 to 600 daN) on the working head of the tube.

The use of a conventional manual apparatus, however, does not allow to work the large diameter tubes of very rigid multilayer materials. The transformation of the force passing through a lever arm into a force on the tube is effected by an engagement of a transmission member, such as a tooth. The angular value of the angle of recovery between two actuations of the lever arm is therefore a function of the dimensioning of the transmission member in engagement, hardly compatible with the desired mechanical strength. In addition, the length of the lever arm is limited by the ergonomics of working with one hand.

In one aspect, the invention aims to design a tool for working the tube that is ergonomic, while allowing to develop high efforts on the work head.

For this purpose, the invention relates to a tool of the aforementioned type, the drive comprising a second pinion with small teeth, secured to the first pinion, the drive and retaining pawls being engaged with the second pinion.

• les premier et deuxième pignons forment un pignon étage venu de matière ;
• la crémaillère est montée à coulissement par rapport au corps ;
• la crémaillère est un secteur denté monté en pivot par rapport au corps ;
• les cliquets d'entraînement et de retenue comprennent des surfaces de contact à engagement mutuel aptes à désengager le cliquet de retenue du deuxième pignon sous l'action d'un mouvement de déverrouillage de la gâchette, permettant ainsi le mouvement de recul de la crémaillère ;
• le cliquet d'entraînement vient au contact d'une came du cliquet de retenue, comprime son ressort de sollicitation, vient en butée arrière puis dégage le cliquet de retenue en comprimant le ressort de sollicitation de ce dernier ;
• les cliquets d'entraînement et de retenue sont identiques ;
• l'outil comprend une tête de travail destinée au cintrage des tubes ;
• l'outil comprend une tête de travail en forme de matrice et une paire de butées latérales destinées à soutenir un tube lors du processus de cintrage et montées sur chaque côté d'un support transversal prévu sur le corps.

According to other preferred features:

• the first and second gables form a sprocket floor come matter;
• the rack is slidably mounted relative to the body;
• the rack is a toothed sector pivotally mounted relative to the body;
• the drive and retaining pawls comprise mutually engageable contact surfaces capable of disengaging the retaining pawl of the second pinion under the action of an unlocking movement of the trigger, thus allowing the recoil movement of the rack;
• the driving pawl comes into contact with a cam of the retaining pawl, compresses its biasing spring, comes to a rear stop and then releases the retaining pawl by compressing the biasing spring of the latter;
• the drive and retaining pawls are identical;
• the tool includes a working head for bending the tubes;
• the tool comprises a die-shaped work head and a pair of lateral stops for supporting a tube during the bending process and mounted on each side of a transverse support provided on the body.

According to another aspect, the invention, according to a preferred embodiment, aims to reduce the unlocking force of the retaining pawl for multilayer tubes, which are very elastic. This problem is solved by the fact that in a tool intended for the work of tubes of the type indicated above, the drive and retaining pawls comprise mutually engageable contact surfaces capable of disengaging the retaining pawl of the second gear under the action of an unlocking movement of the trigger, thus allowing the recoil movement of the rack. More particularly, it is provided, for the unlocking, a a mechanism in which, when the trigger performs an unlocking movement, the drive pawl engages a cam of the retaining pawl, compresses its biasing spring, comes to a rear stop, and releases the retaining pawl by squeezing the spring solicitation of the latter.

• la Figure 1 représente une vue en perspective d'un outil selon l'invention,
• la Figure 2 représente une vue en perspective éclatée de l'outil de la Figure 1,
• les Figures 3A à 3C représentent les étapes d'entraînement de l'outil de la Figure 1,
• les Figures 4A à 4F représentent les étapes de déverrouillage du cliquet de retenue de l'outil de la Figure 1.

The invention will now be described in the context of a manual tube bending application with reference to the appended figures, in which:

• the Figure 1 represents a perspective view of a tool according to the invention,
• the Figure 2 represents an exploded perspective view of the tool of the Figure 1 ,
• the Figures 3A to 3C represent the training stages of the tool of the Figure 1 ,
• the Figures 4A to 4F represent the steps of unlocking the retaining pawl of the tool from the Figure 1 .

The tool of Figure 1 is a manual bender 1 for tube 10, assumed, for the convenience of the description, with its rear right, as shown. The bender 1 is of the crossbow type, and comprises a body 12 on which is articulated an actuating trigger 14 and to which is connected a handle 16 by fixing means. A member 18 integrally supporting a working head 20 is movably connected to the body 12. The working head 20 is in the form of a semi-cylindrical matrix comprising a groove 21 adapted to receive the tube 10 to be bent according to the particular radius desired. A pair of lateral stops 22, intended to support the tube 10 during the bending process, is mounted on either side of a transverse support 24 provided on the body 12.

With reference to the Figure 2 , a drive device 24 of the support member 18 is articulated on the body 12 and connected to the actuating trigger 14. The support member 18 comprises a linear rack 26 having large teeth on its underside. The driving device 24 comprises a transverse shaft 26 which pivots in the body 12 and whose ends form bearings 28 and 30. Pads 32 and 34 are respectively mounted on the bearing surfaces 28 and 30. The shaft 26 comprises, in its intermediate portion, a first pinion 40 with large teeth engaged with the rack 26 and a pinion with small teeth 42 secured to the first pinion 40.

In the example shown, the first and second pinions 40 and 42 form a stepped pinion made of material by molding and ground by machining. The number of teeth of the first pinion 40 is nine; the number of teeth of the second gear 42 is thirty five. The module of the first pinion 40 is 1.25, while the module of the second pinion 42 is 0.6.

The shaft 26, once assembled, is rotatably mounted in the body 12 via bores 36 made in the body 12, and retained in the latter by a circlip 38.

The driving device 24 further comprises a driving pawl 44 and a retaining pawl 46, the two pawls 44 and 46 having small teeth adapted to engage those of the second pinion 42. The driving pawls 44 and retaining 46 are identical and generally parallelepipedal shape. One of the faces of the parallelepiped is shaped so as to form four zones. Each of the drive pawls 44 and retainer 46 respectively comprise a toothed zone 44A, 46A, a smooth and concave clearance zone 44B, 46B, and two cam regions 44C, 46C and 44D, 46D located at opposite ends of the face. profiled.

The driving pawl 44 and the retaining pawl 46 are mounted diametrically opposite and sliding respectively in the handle 14 and in the body 12. The drive pawl 44 provides the forward movement in the desired direction of the rack 26 , while the retaining pawl prevents the recoil movement, in the opposite direction in the desired direction, of the rack 26. Springs 48 and 50, respectively resting on stops 52 and 54 of the trigger 14 and the body 12, respectively urge the driving pawl 44 and the retaining pawl 46 to their engagement position with the second pinion 42.

A helical compression spring 56 whose ends are connected, on the one hand, to the body 12 and, on the other hand, to the trigger 14, urges the latter towards a position spaced from the handle 16. The trigger 14 is hinged in pivot on the body 12 between this position spaced from the handle 16 and a position close to the handle 16. The reciprocating movement of the actuating trigger 14 between the spaced position and the position close to the handle 16 against the the force of the compression spring 56, produces a forward movement in steps of the rack 26 towards the front.

In the crossbow bender example, the rack 26 is slidably mounted relative to the body 12. In other applications, the rack may be a toothed sector pivotally mounted relative to the body 12.

The operation of the advance movement of the rack 26 will now be described with reference to Figures 3A to 3C .

In the Figure 3A , the trigger 14 is in the spaced apart position of the body 16 by an angle of about 15 °. The areas with small teeth 44A and 46A respectively of the drive pawls 44 and retaining 46 are engaged with those of the second pinion 42, while the smooth areas 44B, 46B respectively pawls 44 and 46 do not interfere with the second pinion 42. A force exerted on the trigger 14 along the arrow F of the Figure 3B tends to bring the trigger 14 closer to the handle 16. In the rotational movement in the anti-clockwise direction generated, the drive pawl 44 remains engaged with the second gear 42 and drives the first gear 40 counterclockwise , which produces a forward movement of the rack 26 along the arrow F 'of the Figure 3B . Simultaneously, under the anti-clockwise rotation action of the second pinion 42, the toothed zone 46A of the retaining pawl 46 slides on the teeth of the second pinion 42 and makes a recoil movement along the arrow F "of the Figure 3B , the recoil being against the spring 50.

As indicated on the Figure 3C , continuing the effort tending to bring the trigger 14 of the handle 16, as indicated by the arrow F, the toothed zone 44A of the driving pawl 44 remains in engagement with the teeth of the second pinion 42 and the rotation of the first pinion 40 secured to the second pinion 42 continues, generating the progressive advance of the rack 26 along the arrow F 'of the Figure 3C . Simultaneously, the recoil of the retaining pawl 46 having allowed the passage of the teeth of the second pinion 42, the toothed zone 46A of the retaining pawl 46 is again engaged with the teeth of the second pinion 42 under the effect of biasing the spring 50 following the arrow F "' of the Figure 3C . Under the action of the compression spring 56 urging the trigger 14 to its position spaced from the handle 16 (the spring 56 not being shown on the Figures 3A to 3C for reasons of clarity of the drawings), the toothed zone 46A of the retaining pawl 46 remains in engagement with the teeth of the second pinion 32 and blocks the rotational movement of the second pinion 42 and the first pinion 40 in the clockwise direction. This blocking maintains the rack 26, which is biased to the rear by the bending resistance of the tube being bent, in the advanced position previously obtained. Still under the action of the compression spring 56 and simultaneously, the toothed zone 44A of the drive pawl 44 slides on the teeth of the second pinion 42, causing a recoil movement of the drive pawl 44 against the spring 48. , the ratchet of the drive pawl 44 allowing the trigger 14, in a clockwise movement, to return to its initial position illustrated in FIG. Figure 3A . The recovery angle thus obtained is about 15 °.

A succession of alternating movements of the trigger 14 tending to bring the trigger 14 closer to and then away from the handle 16 thus enables the rack 26 to advance progressively forward. Through the first pinion and second pinion mounted in stages and secured to each other, the input movement of the trigger 14 is decoupled from the advance movement of the rack 26. both large thrust efforts on the working head, thanks to the large teeth of the rack and pinion 40, and a moderate angle of recovery, favorable ergonomics, thanks to the small teeth of the pinion 42.

According to another preferred aspect of the invention, it will now be described the unlocking of the retaining pawl 46, allowing the rack 26 to retract, with reference to the Figures 4A to 4E .

In the Figure 4A , the actuating trigger 14 is in a position spaced approximately 15 ° from the handle 16. The respective toothed areas 44A and 46A of the drive pawls 44 and retaining 46 are engaged with the teeth of the second gear 42 under the yoke. the biasing force of the respective springs 48 and 50. The first pinion 40 and second pinion 42 in floor being held stationary under the action of the retaining pawl 46, the rack 26 remains stationary in advanced position. Under the action of a force tending to move the trigger 14 away from the handle 16 according to the arrow D in the clockwise direction of the Figure 4B , the toothed zone 44A of the drive pawl 44 slides on the teeth of the second pinion 42, a recoil movement of the drive pawl 44 being slid with respect to the trigger 14 against the spring 48 according to the arrow D 'of the Figure 4B .

Continuing the movement of the trigger 14 tending to move it away from the handle 16 according to the arrow D of the Figure 4C , the recoil of the drive pawl 44 against the spring 48 having been sufficient, the toothed zone 44A of the drive pawl 44 passes the peak of the teeth of the second pinion 42, and under the biasing action of the spring 48 , the driving pawl 44 moves forwardly sliding along the arrow D "of the Figure 4C . In this position, the cam region 44C of the drive pawl 44 is opposite the cam zone 46D adjacent to the toothed zone 46A of the retaining pawl 46 and opposite the cam region 46C of the same retaining pawl 46. .

By continuing always the movement of the actuating trigger 14 away from the handle 16 ( Figure 4D ), a ramp 44I of the cam region 44C of the drive pawl 44, ramp adjacent an end face 44H, contacts an edge 46E defined by the intersection of two sliding surfaces 46F and 46G of the cam zone 46D of the retaining pawl 46. Under the effect of the clockwise rotation of the trigger 14, the driving pawl 44 makes a recoil movement represented by the arrow D '''of the Figure 4D Against the spring 48. The cam region 44C of the drive pawl 44 abuts the cam region 46D of the retaining pawl 46, the toothed zone 44A of the drive pawl 44 disengages from the teeth of the second pinion 42 by compressing the spring 48.

By continuing the movement away from the trigger 14 of the handle 16 to reach an angular position of about 30 ° with respect to the handle 16 ( Figure 4E ), the end face 44H of the drive pawl 44 engages the sliding surface 46G of the retaining pawl 46. The end face 44H of the drive pawl 44 and the sliding surface 46G of the pawl 46 are arranged such that the rotation of the trigger 14 in the clockwise direction represented by the arrow D of the Figure 4E , causes the driving pawl 44 to retract and stop on the trigger 14, as represented by the arrow D "" of the Figure 4E . As a result, the toothed zone 44A of the drive pawl 44 is completely disengaged from the teeth of the second pinion 42.

Simultaneously, the contact of the edge 46E of the retaining pawl 46 with the end face 44H of the drive pawl 44 generates, under the action of the rotational movement in the clockwise direction of the trigger 14, a recoil motion retaining pawl 46 against the spring 50 along the arrow D '''' of the Figure 4E , the recoil movement tending to disengage the toothed portion 46B from the retaining pawl 46 of the teeth of the second pinion 42. The tracking beyond 30 ° of the clockwise rotational movement of the trigger 14 of the handle 16 ( Figure 4F ), completely disengages the toothed zone 46B from the retaining pawl 46 of the teeth of the second gear 42. Indeed, the contact of the end face 44H of the drive pawl 44 with the edge 46E and the sliding surface 46G of the pawl 46, followed by the abutment of the ramp 441 of the drive pawl 44 with a surface 46J, located between the sliding surface 46G and the toothed zone 46A of the retaining pawl 46, accentuates the recoil movement of the retaining pawl 46 against the spring 50 along the arrow D '''' of the figure 4F . The toothed zone 46A of the retaining pawl 46 is then totally disengaged from the teeth of the second pinion 42. The first pinion 40 and the second pinion 42 being integral, the driving ratchet 44 and the retaining pawl 46 being disengaged from the teeth. teeth of the second pinion 42, it is then possible to make the rack 26 a recoil movement along the arrow F "" of the Figure 4F . An anti-clockwise movement tending to bring the trigger 14 closer to the handle 16, disengages the cam zone 44C from the drive pawl 44 of the cam zone 46D of the retaining pawl 46 and allows the reengagement of the toothed zones 44A and 46A. respective of the drive pawl 44 and the retaining pawl 46 with the teeth of the second pinion 42. Thus, the tool is ready for a new work cycle.

The invention which has just been described applies to tube bending work, but can be applied to a tube cutting operation, to the installation of rings at the end of tubes or to the expansion of the tube. end of tubes.

Claims (10)

1. Tool designed for working with pipes, of a type which includes a body (12) on which is articulated an operating trigger (14) with an alternating movement and to which is connected, in a moveable manner, an element (18) supporting a working head (20); a device (24) for driving the support element (18) fitted to the body (12) and linked to the operating trigger (14); the support element (18), which includes a toothed gear-rack (26), the drive device (24) including an first toothed pinion (40) which has a first module, with the teeth of the first pinion meshing with the gear-rack (26), a drive ratchet (44) and a retention ratchet (46), the drive ratchet (44) being responsible for the forwards movement in the desired direction of the gear-rack (26), the retention ratchet (46) preventing the backwards motion movement of the gear-rack (26) in the direction opposite to the desired direction, thus allowing a gradual forwards motion under the action of alternating drive movements of the operating trigger, characterised by the fact that the drive device (24) includes a second toothed pinion (42) which has a second module which is less than the first module, with the second pinion being solidly attached to the first pinion (40), with the drive ratchets (44) and retention ratchets (46) being engaged with the second pinion (42).
2. Tool according to claim 1, characterised by the fact that the first pinion (40) and the second pinion (42) are respectively equipped with a first number of teeth and a second number of teeth, and by the fact that the first number of teeth is less than the second number of teeth.
3. Tool according to claim 1 or 2, characterised by the fact that the first (40) and second (42) pinions form a one piece tiered pinion.
4. Tool according to any of claims 1 to 3 whatsoever, characterised by the fact that the gear-rack (26) is mounted so as to slide in relation to the body.
5. Tool according to any of the preceding claims, characterised by the fact that the gear-rack (26) is a toothed sector mounted so as to pivot in relation to the body.
6. Tool according to any of the preceding claims whatsoever, characterised by the fact that the drive ratchets (44) and retention (46) ratchets include mutual engagement contact surfaces (44C, 44E, 44F, 44H, 441 ; 46D, 46E, 46F, 46G, 46J) designed to disengage the retention ratchet (46) from the second pinion (42) under the action of a releasing movement of the trigger (14), thus enabling the backwards movement of the gear-rack (26).
7. Tool according to claim 6 characterised by the fact that the drive ratchet (44) makes contact with a cam (46D) on the retention ratchet (46), compresses its loading spring (50), and comes up against a rear stop then disengages the retention ratchet (46) whilst compressing the latter's loading spring (52).
8. Tool according to any of the preceding claims whatsoever, characterised by the fact that the drive ratchets (44) and retention ratchets (46) are identical.
9. Tool according to any of the preceding claims whatsoever, including a working head (20) intended for bending pipes.
10. Tool according to claim 9, which includes a working head in the form of a mandrel (20) and a pair of side stops (22) intended to support a pipe (10) during the bending process and fitted on each side of a transverse support (24) provided on the body (12).

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