EP1218147B1 - Self-adjusting pliers for single-handed manipulation - Google Patents

Abstract

A pair of pliers which is automatically and continuously self-adjusting. In the approach phase, a mobile branch (2) is guided by a cradle with two intermediate (4) and rear (32) supports.

Description

The present invention relates to pliers adjustable, can be operated with one hand, of the type described in the preamble of claim 1.

EP-A-218 760 describes pliers of this type, in which the mutual guidance of the branches during the phase approach of the clamp is obtained by means of an arm articulated which crosses the space between the two handles. By phase of approach is meant the step use of the pliers in which, in the absence of contact of the two jaws with an object to be grasped, we exercise on the handles of the efforts of adapted directions tending to bring the jaws together.

Such an articulated arm presents as main disadvantages of being a pinch hazard for users' fingers, being exposed to shocks and soiling, and removing all freedom of movement angular of the branches with respect to each other.

The invention aims to provide an adjustable clamp can be operated with one hand, relatively constructed simple, which provides comfort, flexibility and security of improved use while allowing excellent control of the approach phase.

To this end, the invention relates to pliers adjustable of the aforementioned type, characterized by the part Characterizing of claim 1.

The adjustable clamp according to the invention may include one of the characteristics described in claims 2 to 22, taken individually or according to all their technically possible combinations.

• la Figure 1 est une vue schématique d'une pince réglable conforme à l'invention, en position de repos et en phase d'approche ;
• la Figure 2 représente à plus grande échelle un détail de la figure 1;
• la Figure 3 est une vue analogue de la pince de la figure 1, en cours de serrage d'un objet ;
• les Figures 4 et 5 sont des vues analogues de deux variantes de la pince des figures 1 à 3; et
• la Figure 6 est une vue analogue d'un second mode de réalisation de la pince suivant l'invention.

Examples of embodiments of the invention are now described with reference to the appended drawings, in which:

• Figure 1 is a schematic view of an adjustable clamp according to the invention, in the rest position and in the approach phase;
• Figure 2 shows on a larger scale a detail of Figure 1;
• Figure 3 is a similar view of the clamp of Figure 1, during clamping of an object;
• Figures 4 and 5 are similar views of two variants of the clamp of Figures 1 to 3; and
• Figure 6 is a similar view of a second embodiment of the clamp according to the invention.

The adjustable clamp 1 shown in Figure 1 is consisting of two branches 2 and 3, of an organ articulation or finger 4, a support element 5 and a opening spring 6.

Branch 2, or movable branch, consists of a solid metal piece that defines, from front to the rear, i.e. from left to right considering the Figure 1, a movable jaw 7, an intermediate region articulation 8, a rear support region 9 and a handle 10. On the latter can be attached a sheath 11, as shown.

The jaw 7 has a toothed upper face 12 for entering an object 13. The face 12 has end regions 12A, 12B, substantially flat and coplanar, separated by a very open V-shaped region 12C.

The support region 9 has a lower surface convex 14 in the shape of an arc of a circle whose center 0 is a virtual point located clearly outside the contours of the tool, above it. The upper surface 15 of branch 2, in the same region, is straight and close of the string that underlies the arc 14.

The handle 10 is curved, with its convexity directed upwards.

Branch 3, or fixed branch, defines before and rear a fixed jaw 16, attached to the main part of the branch by means of rivets, an intermediate region articulation 17, a rear support region 18 and a handle 19 coated with a sheath 20.

The jaw 16 has on its underside a toothing 21 with two roughly flat and coplanar zones 21A, 21B framing a very open V-shaped zone 21 C. As shown in the drawing, in the V-shaped areas of the jaws, only the rear part of zone 12C and the front part of zone 21C are toothed.

Region 17 has a general arcuate shape and center O. It is bounded by lower surfaces and upper smooth 22 and 23 in the form of arcs of a circle of center O, and has an arcuate light 24. This is delimited by a smooth upper surface 25 and by a bottom surface 26 serrated forming a rack. Each of surfaces 22 to 25 as well as the mean line of the surface 26 are arcs of a circle with center O. The jaws 7 and 16 lie entirely outside the circle of largest radius 22.

• une surface supérieure concave 28, circulaire et de même rayon que la surface 25 ;
• une surface inférieure qui présente à l'arrière une denture de blocage 29 en dents de scie, adaptée pour venir en prise avec la denture 26, et à l'avant un bossage 30.

The articulation member 4 (FIG. 2) is a piece of elongated shape freely articulated approximately at mid-length by a pivot 27 on the region 8 of the branch 2. This piece comprises:

• a concave upper surface 28, circular and of the same radius as the surface 25;
• a lower surface which has at the rear a blocking teeth 29 in sawtooth shape, adapted to come into engagement with the teeth 26, and at the front a boss 30.

In its support region 18, the fixed branch 3 furthermore comprises a blind housing 31 open towards the top in which a slide 32 is received. The latter is pushed up by a spring 33, which is here a compression coil spring, to a position of rest as shown, in which the slide is resting on a stop (not shown) secured to the branch 3. The slide 32 has at its upper part a support projection 34 for the support surface 14 of the branch 2.

The opening spring 6, which is much more weak than the spring 33, is a helical spring of tensile tension between a point 35 of branch 3 near the housing 31 and a point 36 of branch 2 adjacent to the pivot 27 of the member 4 and located between the arcs 22 and 26.

In Figure 1, the movable branch 2 is shown in thin line in rest position and in thicker line in approach course.

At rest, under the effect of the spring 6, the jaw 7 is pulled to its maximum jaw spacing position 16. To reach this position, the surface 14 slides on the protrusion 34 of the slide 32, until the member 4 abuts the rear end (right end on the FIG. 1) of the light 24. Of course, as a variant, other abutment means can be provided to limit the opening of the two jaws.

To enter an object 13, we first proceed to an approach phase by exerting on both handles a effort F of approximation, as illustrated by the arrows.

Due to the relative hardness between the two springs 6 and 33, this effort firstly causes a slight tilting of the branch 2 around the protuberance 34, until the upper surface 28 of finger 4 applies to the upper surface 25 of the light 24.

The continuation of the same effort causes the slip to the left of the surface 14 on the protuberance 34 and, simultaneously, that of the surface 28 of finger 4 along the surface 25, a slight clearance existing between the finger and the toothing 26. The two intermediate support points 28 and rear 34 form a movement guide cradle approach to branch 2.

So, throughout the approach, point 34 is fixed relative to branch 3. In some cases, a sudden force exerted on the handles can cause slight compression of spring 33, but this resumes immediately its original length. Point 34 is therefore always fixed or substantially fixed in relation to the branch 3.

During the whole approach, the normals N1 and N2 at contact points 28, 34 of the guide surfaces 25 and support 14 form a V whose point is directed towards the high, that is to say on the side opposite the jaws. This V can have an angle slightly less than 90 ° as shown or, in variant, an angle substantially equal to 90 °.

This approach movement, which takes place against of spring 6, continues until contact between the two jaws with the object 13, then the contact of the boss 30 with the toothing 26 swings finger 4 around its pivot 27 and brings the teeth 29 into contact with the teeth 26 (Figure 3).

The point of contact of the movable jaw 7 with this object then defines a center of rotation, and the pursuit of the effort of bringing the two handles together causes the tilting of branch 2 around this center.

This movement, which is enabled by compression of the rear spring 33, causes the engagement and blocking of teeth 29 in teeth 26, which forms a new center rotation for branch 2. Continued effort exerted on the two handles tends to tilt the branch 2 around this new center, which ensures the effect tightening the object 13. In this phase, the finger is in bracing between the teeth 26 and the surface 25.

When you release the effort exerted on both handles, the teeth 29 emerge from the bottom of the teeth 26 under the effect of spring 33. The opposite end of the finger having remained in contact with the surface 25, this displacement upwards causes the finger to tilt around its pivot 27. Thus the finger quickly resumes its position initial guide on the surface 25, and the spring 6 then recall the entire branch back to the maximum spacing of the jaws.

The clamp thus described has a construction relatively simple and provides great softness and high precision during the approach phase. In addition, the general concave shape of the intermediate region of the tool, obtained thanks to surfaces 23 and 15, makes it possible to slide the front part of the pliers into slots difficult to access, for example behind a pipe. Likewise, the arcuate shape of the lower surface 22 gives the tool has a particularly sharp general profile.

It should also be noted that thanks to its shape arched, the light 24 can easily include a part rear whose orientation approximates that of the movable handle 10. This reduces the effort to be exerted on the handles to start the approach, relative to the case usual where the light is rectilinear as in EP-A-218 760 cited above.

Furthermore, no organ extends between the rear parts of the two arms, which protects the fingers of the user.

It is provided on branch 2, at the back of the jaw 7, a protruding nipple 37. From a certain degree opening the handles, this stud abuts on the surface 22, which limits the opening of the handles.

• la lumière 24 est rectiligne, de même que la surface inférieure 22. Les surfaces 22, 25 et la ligne moyenne de la surface 26 sont parallèles entre elles ;
• la surface supérieure 23 est sensiblement rectiligne, avec une orientation qui diverge vers l'arrière par rapport à celle de la lumière 24 ; la branche 3 présente en regard de cette surface 23 une surface inférieure 23A sensiblement parallèle à cette dernière ;
• la surface d'appui 14 est rectiligne et sensiblement parallèle à la surface supérieure 15 ;
• cette surface 14 s'appuie, en roulement et/ou en glissement, sur un galet 38 porté par l'extrémité supérieure du coulisseau 32 ; et
• la zone distale de la poignée 19, adjacente à la région d'appui 18 , comporte un évidement 39.

The variant of Figure 4 differs from the previous one in the following points:

• the light 24 is rectilinear, as is the lower surface 22. The surfaces 22, 25 and the middle line of the surface 26 are parallel to each other;
• the upper surface 23 is substantially rectilinear, with an orientation which diverges backwards with respect to that of the light 24; the branch 3 has opposite this surface 23 a lower surface 23A substantially parallel to the latter;
• the bearing surface 14 is straight and substantially parallel to the upper surface 15;
• this surface 14 is supported, in rolling and / or sliding, on a roller 38 carried by the upper end of the slide 32; and
• the distal zone of the handle 19, adjacent to the support region 18, has a recess 39.

Due to the recess 39, the lower surface of the handle 19 closest to the jaws defines two zones support, proximal 40 and distal 41, whose lines respective averages 42 and 43 form a certain angle. So compared to the inner line average 44 of the fixed jaw 16, the line 42 makes an angle x1 between 45 and 55 ° and preferably 50 °, while line 43 makes an angle x2 significantly larger than x1, by around 75 to 90 °.

The handle 10 furthest from the jaws has a convex top surface, which defines an area proximal 45 and a distal area 46 whose middle lines respective 47 and 48 form a certain angle between them. Compared to the average interior line 49 of the movable jaw 7, line 48 forms an angle y1 of 45 to 55 ° and preferably 50 °, while line 47 forms an angle y2 larger, of the order of 75 to 90 °.

The pair of surfaces 41 and 45 facilitates the phase approach to the clamp, described above, thanks to the orientation of the F1 approximation effort which is exerted on them. The pair of surfaces 40 and 46 facilitates the effort tightening of the object seized, thanks to the orientation of the force F2 exerted on them.

• d'une part, la lumière 24 est arquée, c'est-à-dire que sa surface 25 et la ligne moyenne de sa surface 26 sont des arcs de cercle de centre 0 ;
• d'autre part, la surface d'appui 14 est également un arc de cercle, mais son centre O' est distinct du point O.

The variant of Figure 5 is similar to that of Figure 4, with two differences:

• on the one hand, the light 24 is arcuate, that is to say that its surface 25 and the mean line of its surface 26 are arcs of a circle with center 0;
• on the other hand, the bearing surface 14 is also an arc of a circle, but its center O 'is distinct from the point O.

The embodiment of Figure 6 operates from analogous to what was described above, but with a structure modified as follows with respect to the embodiment of Figures 1 to 3.

Light 24 is deleted. Rack 26 is formed on the upper surface 23 of the region intermediate 17 of the fixed branch, and the jaw 7 has, at the rear and at the bottom, a spout 50 directed towards the rear. The rack 26 extends backwards through a surface smooth support 114.

The slide 32 is carried by the movable branch 2, facing the surface 114, and is biased downwards, up to a predetermined limit position by a stop not represented by spring 33.

Points 35 and 36 for hooking the spring opening 6 are located respectively at the end rear of handle 19 and slightly behind the slide 32.

The finger 104 is articulated, by means of the pivot 27, on the branch 2 so that the teeth 29 are at a distance from the spout 50 greater than the thickness of the part 17, this under the action of a spring 51 which maintains the surface front 30 of the finger in contact with the rear face of the intermediate part 17 of the fixed branch 3.

At rest, the spring 6 holds the two jaws in position of maximum spacing, this position being determined by appropriate stops (not shown) of the two branches.

When we start to bring the two handles together, branch 2 rotates slightly clockwise around of the point of contact between the slide 32 and the surface 114, which moves the axis 27 away from the rack 26 and brings the spout 50 in contact with the surface 22.

The continuation of the merger effort on both handles causes simultaneous movement towards the front of the slide 32 on the surface 114 and the spout 50 on surface 22, until the two jaws reach the contact with object 13 (figure 6). We find the V with point at the top and at an acute angle formed by the normals N1 and N2, as described above.

If we keep bringing the two handles closer together, the branch 2 first pivots around its point of contact with object 13, by compressing spring 33, until the teeth 29 of finger 104 are blocked in rack 26. Then this engagement defines a new rotation center of branch 2, which allows the object 13 to be clamped as previously. Thanks to the action of the spring 51, the teeth 29 are released from the rack 26 when the gripper handles.

Claims (22)

1. Adjustable pliers which can be operated with one hand only, comprising two arms (2, 3) which cross over each other, each of which defines a jaw (7, 16) and a handle (10, 19), each arm comprising an intermediate articulation area (8, 17) located between its jaw and its handle,
      a first arm (3) having in its intermediate region (17) on the one hand a guiding surface (25; 22) elongated in shape, along which a means of guiding (28;50) integral with the intermediate region of the second arm (2) and, on the other hand, an articulation area (26) along which a means of articulation (4;104) can be positioned,
      the pliers having means (29) of locking the articulation means (4; 104) along the articulation area (26),
      characterised in that they have a rear supporting region which is defined on the one hand by a part (5) supporting one arm and, on the other hand, by a surface (14; 114), elongated in shape, supporting the other arm adapted to work in conjunction with this supporting part as a mutual movable support along the supporting surface,
      the supporting part (5) and the supporting surface (14; 114) being located between the intermediate region (8, 17) and the handle (10, 19) of the respective arms,
      the arrangement being such that during the pliers approach stage, in each position of the arms, the supporting surface (14; 114) and the supporting part (5) both remain in a more or less fixed position in relation to the respective arms and a relative movement simultaneously occurs of the guiding means (28; 50) along the guiding surface (25; 22) and a relative movement of the supporting part (5) along the supporting surface (14; 114).
2. Pliers according to Claim 1, characterised in that the area where each handle (10, 19) is held has a near region (40, 45) and a farther away region (41, 46), the mean line (47) of the near region (45) of the handle (10) farthest away from the jaws (7, 16) forming with the inside mean line (49) of the associated jaw (7) a greater angle (y2) than that (y1) formed with this inside mean line (49) by the mean line (48) of the farther away region (41) of the same holding area, while the mean line (42) of the near region (40) of the other handle (19) fonns with the inside mean line (44) of the associated jaw (16) a smaller angle (x1) than that (x2) formed with this inside mean line (44) by the mean line (43) of the farther away region (41) of the same holding area.
3. Pliers according to Claim 1 or 2, characterised in that the holding area of each handle (10, 19) has a near region (40, 45) and a farther away region (41, 46), the near region (45) of the handle (10) farthest away from the jaws and the farther away region (41) of the other handle (19) constituting the pair of surfaces held in the hand during the approach stage, the farther away region (46) of the handle (10) farthest away from the jaws and the near region (40) of the other handle (19) forming the pair of surfaces to be held in the hand during the tightening stage.
4. Pliers according to Claim 3, characterised in that each of the regions (40, 46) constituting the pair of surfaces to be held in the hand during the tightening stage, form, at one point at least, with the mean inside line (44, 47) of the jaw of the arm which carries this region, an angle (x1, y1) between 45° and 55°, preferably 50°.
5. Pliers according to Claim 3 or 4, characterised in that each of the regions (41, 45) constituting the pair of surfaces for holding in the hand during the approach stage, form, at one point at least, with the mean inside line (44, 47) of the jaw of the arm which carries the said region, an angle (x2, y2) of between 75° and 90° inclusive.
6. Pliers according to any one of the Claims 1 to 5, characterised in that the handle (19) nearest the jaws defines on its outer side an indent (39) where it joins the rear supporting region (18).
7. Pliers according to any one of the Claims I to 6, characterised in that, in all approach positions of the arms, the perpendiculars at the points of contact of the guiding surface (25; 22) and of the supporting surface (14; 114) form a V, the point of which is directed towards the side of the arms opposite the jaws, the angle of the V in particular being more or less equal to 90°.
8. Pliers according to any one of the Claims 1 to 7, characterised in that the guiding surface (25; 22) is arched; in particular circular, with a virtual centre of curvature (0) located outside the overall perimeter of the assembly of the two arms (2, 3) and on the side of the guiding surface opposite the jaws (7, 16).
9. Pliers according to any one of the Claims 1 to 8, characterised in that, in its intermediate region, the first arm (3), as from its jaw (7) and on its edge turned towards the latter, has an arched profile (22), in particular circular, with the concavity turned towards the side of the arms (2, 3) opposite the jaws (7, 16).
10. Pliers according to any one of the Claims 1 to 9, characterised in that the supporting surface (14; 114) is arched, in particular circular, with a virtual centre of curvature (0; 0') located outside the overall perimeter of the arms (2, 3) assembly and on the side of the supporting surface opposite the jaws (7, 16).
11. Pliers according to Claims 8 and 10 taken together, characterised in that the two centres of curvature (0, 0') are adjacent to each other in all the approach positions of the arms (2, 3).
12. Pliers according to Claims 8 and 10 taken together, characterised in that the two centres of curvature (0) are merged together.
13. Pliers according to any one of the Claims 1 to 12, characterised in that the said supporting part (5) works in conjunction with the said supporting surface (14; 114) by sliding and/or rolling.
14. Pliers according to any one of the Claims 1 to 13, characterised in that the supporting surface (14; 114) works as a simple support in conjunction with the supporting part (5).
15. Pliers according to any one of the Claims 1 to 14, characterised in that the supporting part (5) is acted upon by a spring (33) in the direction of the supporting surface (14; 114) and towards a predetermined stop position.
16. Pliers according to Claim 15, characterised in that the supporting part (5) can be retracted against the spring (33) when a force mutually bringing the handles (10, 19) towards each other is exerted while the jaws (7, 16) are catching on an object to be tightened (13) and the locking means (29) are active.
17. Pliers according to Claim 16, characterised in that the locking means (29) are activated by the jaws (7, 16) catching on the said object (13) and the said force for coming together continues.
18. Pliers according to Claim 16 or 17, characterised in that the locking means (29) are deactivated by the relaxing of the said coming-together force.
19. Pliers according to any one of the Claims 16 to 18, characterised in that the means of articulation (4) consist of a finger freely articulated on the second arm (2).
20. Pliers according to any one of the Claims 16 to 18, characterised in that the means of articulation (104) consist of a finger flexibly acted upon towards release of its locking means in relation to the articulation surface (26).
21. Pliers according to any one of the Claims 16 to 20, characterised in that the spring (33) is incorporated in the arm which carries the supporting part (5).
22. Pliers according to any one of the Claims 1 to 21, characterised in that they have a distancing spring (6) which stretches to hold the two jaws (7, 16) permanently apart from each other.

Images