EP3411188A1

EP3411188A1 - Pliers

Info

Publication number: EP3411188A1
Application number: EP17703369.3A
Authority: EP
Inventors: Andreas Heinsohn
Original assignee: Knipex Werk C Gustav Putsch KG
Current assignee: Knipex Werk C Gustav Putsch KG
Priority date: 2016-02-04
Filing date: 2017-02-01
Publication date: 2018-12-12
Anticipated expiration: 2037-02-01
Also published as: US10751857B2; ES2803212T3; DE102016101927A1; WO2017134074A1; RU2731622C2; RU2018131514A; CN108698208B; EP3411188B1; TW201731638A; RU2018131514A3; PL3411188T3; CN108698208A; TWI726044B; US20190039214A1

Abstract

The invention relates to a pair of pliers (1) having two pliers legs (2, 3) that are arranged in a crossing manner, wherein a fixed joint is formed, having a joint pin (8), wherein the joint pin (8) has, in any case assigned to an outer side (18) of a pliers leg (2, 3), a first conical portion (19) that widens towards the outer side (18), wherein, furthermore, the pliers leg (2, 3) is assigned a second conical portion (21) which bears on the first conical portion (19) and transitions into a first mouth portion (22) that leads into the outer side (18) of the pliers leg (2, 3). In order to configure a pair of pliers of the type in question in a further improved manner, it is proposed that the joint pin (8) has a second mouth portion (20) which, starting from the outer side (18) of the pliers leg (2, 3) and perpendicularly to a joint axis (x), overlaps the first mouth portion (22), wherein the first and the second mouth portion (22, 20) bound a circular clearance (23) between one another in a radially encircling manner, the radial dimension (a) of said clearance (23) corresponding to 0.05 to 0.15 times the radial dimension (b), measured from the joint axis (x), of the joint pin (8) in the region of the second mouth portion (20).

Description

description

tongs

Field of engineering

The invention relates to a pair of pliers with two crossed pliers legs, wherein a fixed joint is formed with a hinge pin, wherein the hinge pin in any case associated with an outer side of a pliers leg has a widening towards the outside first cone portion, wherein further the pliers legs a has associated second cone portion which rests against the first cone portion and merges into a, opening into the outside of the forceps leg, first mouth portion.

PRIOR ART Pliers of the type in question are known. The criss-crossing pliers legs can form an applied or inlaid joint in the crossing region, for example. This joint is fixed, i. The joint axis is not changeable in their positioning to both pliers legs. Further known in connection with such pliers hinge pin in the manner of an inserted rivet. The hinge pin passes through the pliers legs in each case in the region of a joint eye.

In order to minimize a notch effect between the hinge pin and the joint eye in the pliers leg especially when using the pliers by acting on the joint formation, possibly high forces, it is also known, the hinge pin with a to the outside of the associated pliers limb toward widening first cone section Mistake. In this respect, it is also known that the conical enlargement of the cone section extends as far as the broad surface of the forceps limb given by the outside of the forceps limb. In the known state of the art, this first cone section of the hinge pin rests on a second cone section formed in the region of the joint eye of the associated pliers limb.

In addition, embodiments are known in which the second cone section in the region of the pliers leg, corresponding to the second cone section in the region of the joint eye, merges in the direction of the outside of the pliers limb into a first mouth section. This can have a maximum diameter corresponding to the enlarged cone diameter. Accordingly, in such embodiments, the second cone section in the pliers limb can not be further radially expanded into the outer surface of the pliers limb. Rather, the uniform cone extension can be interrupted in the direction of the outside by the formation of the first mouth portion.

Summary of the invention

In view of the known prior art, a technical problem of the invention is seen in a pliers of the type in question functionally further improved design. A possible solution to the problem is given according to a first inventive concept in a pair of pliers, in which it is geared to that the hinge pin has a second mouth portion, starting from the outside of the forceps leg and perpendicular to a (geometric) hinge axis in coverage to the first mouth portion is, wherein the first and the second mouth portion radially circumferentially between them limit circular free space whose radial dimension corresponds to 0.05 to 0.15 times the measured from the joint axis radial dimension of the hinge pin in the region of the second mouth portion.

Correspondingly, the conical radial extension, in particular a uniform conical extension of the hinge pin by forming an end, starting from the first cone section towards the associated outer surface of the forceps leg extending second mouth section be interrupted. The second mouth portion may, as also preferably, have the maximum radial extension dimension (starting from the geometric joint axis) of the first cone portion.

Further, starting from the hinge axis of the second mouth portion of the hinge pin in the region of the joint eye in the associated forceps arms - viewed perpendicular to the extension of the hinge axis - formed in coverage to the first mouth portion. The radial overlap of the second mouth portion to the first mouth portion or vice versa may be completely or even partially, for example. Half of the extent considered in the direction of extension of the hinge axis extension, further example. To a third or a quarter provided.

It may, as also preferred, by the formation of the two mouth portions following the cone sections a reduction in diameter of both the Gelenkauges and the hinge pin in the mouth region of the Gelenkauges arise, this compared to a training in which one or both Conical sections is formed evenly extending through to the mouth area. With the same sufficient stability of the joint bolt and the joint bolt connection as a whole, this can be considered as a transversely and thus radially to the geometrical joint axis. th narrow design of the pliers legs lead. Due to the addition of the first and second cone section, the notch effect is kept low.

This can be further supported by the preferably provided annular free space. It may, as also preferred, no direct contact of the hinge pin-side second mouth portion result on the pliers leg-side first mouth portion. On the contrary, in a preferred embodiment, the lateral surfaces of the mouth sections, which face one another in the radial direction, are circumferentially spaced relative to one another with respect to the articulation axis. The distance dimension in the free space can be chosen the same all around. The radial dimension of the annular free space can, as is preferred, be selected such that a possible capillary transport of a lubricant reservoir provided between the lateral surfaces of the joint pin and the respective joint eye is thereby interrupted axially outwards. Also, in the annular space a lubricant stock accumulate if necessary, which can then be sucked in again via the capillary effect axially inward.

In addition, the radial dimension of the annular free space is preferably chosen so low that in this no, the movement of the pliers optionally adversely affecting pollution, for example. In the form of chips or the like., Can settle.

Thus, in an exemplary maximum radial dimension of the hinge pin in the region of the second mouth portion of 4.5 to 5.5 mm, preferably about 4.9 mm, a radial dimension of the circular clearance of 0.35 to 0.55 mm, preferably about 0.45 mm, given. Further features of the invention are explained below, also in the figure description, often in its preferred association with the subject matter of claim 1 or to features of further claims. But they can also be in an assignment to only individual features of claim 1 or the respective further claim or each independently of importance.

Thus, in a further embodiment of the first and / or second mouth portion in a cross section in which the hinge axis is a line, with the hinge axis form an acute angle. Such a acute angle can be greater than zero up to, for example, 20 or 30 degrees, the inclination of the mouth section wall, in particular of the hinge pin, starting from the cone section and being directed radially outwards relative to the hinge axis, but also radially inward can. At an acute angle of zero degrees results in a preferred cylindrical shape of the mouth portion.

Preferably, the inclination angle of the mouth portion to the hinge axis is smaller than the inclination angle of the associated cone portion relative to the hinge axis.

In a further embodiment it can be provided that a measured in the direction of the hinge axis length of the second mouth portion is greater than a measured in the direction of the hinge axis length of the first mouth portion. It follows, as preferred, that the second cone portion of the forceps limb in the region of the joint eye in the direction of the outside of the forceps leg in a preferred embodiment beyond the transition from the first cone portion in the second mouth portion of the hinge pin can extend. Which surrounds the Steering pin resulting line in the transition from the first cone portion in the second mouth portion may rest against the second cone portion of the forceps leg.

The longitudinal dimension, measured in the direction of the joint axis, of the second mouth section in the region of the joint pin can, as is preferred, correspond to 1.5 to 2.5 times the longitudinal dimension of the tangendose first mouth section considered in the same direction. Thus, an embodiment may result in which the second mouth portion is (only) formed over a part of its axial length in a radial opposing position to a portion of the second cone portion.

The axial length of the second mouth portion may correspond in a further embodiment, a 0.1 to 0.3 times the measured from the hinge axis radial dimension of the hinge pin in the region of the second mouth portion. Thus, with an exemplary radial dimension of the hinge pin in the region of the second mouth section of 4.5 to 5.5 mm, preferably about 4.9 mm, an axial length of the second mouth section of 1 to 1.5 mm, for example about 1, 2 mm, yield.

The axial length of the first mouth section may also correspond to 0.05 to 0.15 times the radial measurement of the hinge pin in the region of the second mouth section as measured from the joint axis. Starting from an above-described radial exemplary dimension of the hinge pin, a length of the first mouth section of 3.5 to 5.5 mm, preferably about 4.5 mm, may result.

Both mouth sections may, as also preferred, in the same, perpendicular to the hinge axis extending outside of the associated Pass over the pincer leg or hinge pin. Correspondingly, an embodiment can be provided in which the surfaces of hinge pins and pliers legs, which run perpendicular to the hinge axis and into which surfaces the respective outlet sections terminate, extend in a common plane.

The above-described embodiment with respect to the first and second mouth portions, possibly also in conjunction with the first and second cone sections, may relate solely to an axial end portion of the hinge pin and the cooperating hinge eye in the pliers leg, but beyond on both axial end regions.

In a further preferred embodiment, the forceps on a going through the hinge axis axis of symmetry on which working areas of the forceps arms are movable towards each other. The working areas of the pliers legs can be, for example, jaw surfaces or cutting edges which are formed on pliers jaws formed from the pliers limbs. Further, such a pliers, for example, as a pipe wrench, side or center cutter, further example. As gripping tongs or as a combination pliers known.

On the axis of symmetry of the work areas associated first annular wall portion is provided. This annular wall section at least partially surrounds the hinge pin. Accordingly, the annular wall section extends substantially transversely to the geometric hinge axis. In a preferred embodiment, this first annular wall section assigned to the work areas may have a thickness corresponding to one half to one third of the radial dimension of the hinge pin in the region of the second mouth section. The thickness or material thickness of the first annular wall section which is considered perpendicular to the joint axis can, in the case of an exemplary ma- ximalen radial dimension of the second mouth portion of 4.5 to 5.5 mm, preferably about 4.9 mm, about 2 to 2.5 mm.

The geometric axis of rotation is formed by this training relatively close to the work areas. This leads to a favorable

Force on actuation of the pliers legs. In particular with pliers with cutting work areas, this results in a cutting technically favorable lever arm.

By the described embodiment of the hinge pin following a conically widening area while maintaining a high stability and taking into account the smallest possible notch effect such a narrow yet stable formation of the first annular wall section is possible. Compared to a hinge pin configuration, in which the cone section extends into the plane of the outer side of the pliers limb, with the first annular wall section of equal thickness, there is a lever arm technically favorable displacement of the geometric hinge axis along the axis of symmetry in the direction of the working regions of the pliers limbs ,

Also, a first annular wall portion opposite in the direction of the axis of symmetry second annular wall portion have an approximately the diameter of the hinge pin in the region of the second mouth portion corresponding thickness, further example. An approximately 0.75 to 2 times thickness.

It may result in a design in which the second annular wall portion has a relation to the first annular wall portion substantially larger, considered transversely to the geometric hinge axis thickness, so for example. A relation to the first annular wall portion 2- to 5-times thickness. Consequently When considering the surrounding of the hinge pin Zangenschen- kelabschnittes in the field of enforcement - with regard to the outside of the pliers limb - a displacement of the geometric hinge axis along the axis of symmetry from the center of the area out in the direction of the working areas. This offset also forms a favorable condition with regard to a wide opening of the limited by the jaws jaws pliers.

With regard to the disclosure, the ranges and value ranges or multiple ranges given above and below also include all intermediate values, in particular in 1/10 increments of the respective dimension, if appropriate also without dimensions. For example, the phrase 0.05 to 0.15 tray also includes the disclosure of 0.06 to 0.15 tray, 0.05 to 0.14 tray, 0.06 to 0.14 tray , etc., the disclosure of 0.1 to 0.3 tray also the disclosure of 0.11 to 0.3 tray, 0.1 to 0.20 tray, 0.11 to 0, 29-Fach etc. This disclosure may serve on the one hand to delimit a specified range limit from below and / or above, alternatively or additionally, but to the disclosure of one or more singular values from a respective specified range.

Brief description of the drawings

The invention is explained below with reference to the accompanying drawing, which illustrates only exemplary embodiments. A part which is explained only with reference to one of the exemplary embodiments and is not replaced by another part due to the special feature found there is thus also described for this further exemplary embodiment as an existing part that is possibly possible. On the drawing shows: Fig. 1 a pair of pliers in front view, a first embodiment concerning;

Fig. 2 is a side view thereof;

Fig. 3, the opposite side view; 4 shows the pliers in rear view;

5 shows the pliers in plan view;

6 shows the pliers in bottom view;

7 shows the pliers in perspective view;

FIG. 8 shows the enlargement of the area VIII in FIG. 1; FIG. 9 shows the section along the line IX-IX in Figure 8;

FIG. 9a shows the enlargement of the region IXa in FIG. 9; FIG.

10 is a partial sectional view along the line X-X in Figure 8;

Fig. 11 is a representation corresponding to Figure 8, a second embodiment of the pliers regarding. Description of the embodiments

Shown and described is first with reference to Figure 1, a pair of pliers 1. This is formed in the illustrated in Figures 1 to 10 first embodiment as a side cutter. The following statements relate not only to such a side cutter, but to all sorts of pliers with a fixed hinge pin, so on, also on a pair of pliers 1 in the manner of a combination pliers as shown in Figure 11.

The forceps 1 has two crossing arranged pliers legs 2, 3. In this case, each pliers limb 2, 3 forms a handle leg 4, 5, which merges into a pliers jaw 6, 7 beyond the crossing region of the pliers limbs 2, 3.

The gripping leg 4 and the jaw 6 form the pliers leg 2; Grip leg 5 and jaw 7 the pliers legs. 3

In the illustrated embodiment, the joint (trade) of the forceps 1 is designed as an inserted joint, for which purpose the forceps legs 2, 3 have material notches in the intersection region, in which cut-out regions engage sections of the other forceps limb.

The fixed joint is further given by a hinge pin 8. This penetrates the pliers legs 2, 3 in the transition region from the respective gripping leg into the pliers jaw.

A body axis of the hinge pin 8 at the same time forming geometric hinge axis x extends perpendicular to a plane in which the forceps arms 2, 3 move upon actuation of the forceps 1. The hinge pin 8 is preferably a solidly formed rivet bolt.

Moreover, the pliers 1 are designed to be substantially symmetrical, with respect to an axis of symmetry y extending through the joint axis x, to which working regions 9, 10 of the pliers limbs 2, 3 can be moved towards one another. These work areas 9, 10 are formed in the first embodiment of the forceps 1 as a side cutter by cutting. When forming the pliers 1 in the form of a combination pliers as shown in Figure 11, different working areas 9, 10, which line up along the axis of symmetry y, so a cutting area, a gripping area and a final flat nose area arise.

Work areas 9, 10 in the form of cutting or flat jaws meet in the forceps jaw closing position according to the illustration in Figures 1 and 11 on the axis of symmetry y to each other.

The hinge pin 8 passes through in the crossing region of the pliers each pliers limb 2 in the region of a joint eye 11, 12 formed here.

The hinge pin 8 is preferably in the form of an insertion rivet, which is inserted in the direction of extension of the hinge axis x from one side through the hinge eyes 11, 12 of the pliers legs 2, 3, after which a corresponding rivet deformation of the first end section considered in the insertion direction is performed , for example by tumbling rivets.

The rivet bolt consists for this purpose essentially of a head part 13 and a shaft part 14. The head part 13 finds in one of the pliers legs 2 a substantially positive reception in the relevant joint eye 11, while the shaft part 14 both pliers legs 2 and 3 in Industrial or joint area protrudes. The shank part 14 is made so long for the intended riveting that a shank part protruding from the tong limbs 2 and 3 which can be riveted together can be formed into a rivet recess 15 towards the head part. The illustrations each show a pair of pliers 1 with a hinge pin 8 after completion riveting.

In particular, for the purpose of a favorable adjustment, the head part 13 a in the transverse to the hinge axis x aligned bolt surface 16 opening central blind hole 17. This extends in the direction of the joint axis x approximately over half the axial extent of the head part 13.

[0044] The following statements with regard to the design of the hinge pin section and the associated joint eye relate to the head part 13 of the hinge pin 8 and the hinge eye 11 in the pliers limb 2. However, this embodiment described is also alternatively or in combination possible in the region of the opposite end of the Articulated bolt 8 in cooperation with the joint eye 12 of the forceps leg. 3

Starting from the shaft part 14 and thus essentially determining the head part 13, the hinge pin 8 assigned to the transverse to the hinge axis x aligned outside 18 of the forceps leg 2 to the outside 18 toward expanding first cone portion 19. This first cone section 19 of the hinge pin 8 merges into an end-side second mouth section 20, the bolt surface 16 of which preferably extends in the plane indicated by the outside 18 of the pliers limb 2. The formed in the pliers leg 2 hinge eye 11 facing the other pliers leg 3 has a cylindrical portion on which the outer wall of the shaft portion 14 is supported. This cylindrical region goes in the direction of the outer side 18 into a second cone section 21, which terminates in a first mouth section 22 at the end. This first mouth section 22 merges into the outside 18 of the forceps leg 2.

At the second cone portion 21 of the first cone portion 19 of the hinge pin 18 abuts. As can be seen in particular from the enlarged illustration in FIG. 9a, with respect to the mouth sections 20, 22, a circular-cylindrical configuration with respect to the joint axis x can result. The circumferential walls of both mouth portions 20, 22 extend in cross section according to FIG. 9a in a parallel orientation to the joint axis x. Alternatively, the wall of the mouth portion 20 and / or 22, starting from the cone portion 19, 21 include an acute angle to the hinge axis x of, for example, up to 15 degrees (see dash-dotted wall curve in Fig. 9a), with respect to the wall curve of the second and / or first mouth portion 20, 22 starting from the cone portion 19, 21 may be given an inclination of the wall radially inward or radially outward.

The circumferential surface of the bolt-side second mouth portion 20 is radially inwardly spaced with respect to the hinge axis x to the circumferential inner surface of the shell-side first mouth portion 22. It results so circumferentially to the hinge axis x circular free space 23, which is closed with respect to a cross-section as shown in Figure 10 substantially three-sided and opens only to the outside 18 out.

The clearance 23 has a maximum, i. preferably in the plane of the outer side 18 measured, radial dimension a, which corresponds to 0.05 to 0.15 times the measured from the joint axis x radial dimension b of the hinge pin 8 in the region of the second mouth portion 20. In the illustrated embodiment, the radial dimension a of the free space 23 corresponds approximately to 0.085 times the radial dimension b in the region of the second minting section 20.

[0052] It follows further from this that, viewed in the direction of the joint axis x, the axial length of the joint bolt-side second orifice portion 20 is greater than the axial length of the first orifice portion 22 in the pliers limb 2 considered in the same direction. In the exemplary embodiment illustrated, as shown In FIG. 10, the length c of the thigh-side first mouth section 22 corresponds approximately to 0.4 to 0.5 times the length d of the bolt-side second mouth section 20.

Also, the length c of the leg-side first mouth section 22 may correspond to 0.9 to 1.1 times, moreover approximately to 1 times the radial dimension a of the free space 23.

Next results from the above dimensions, with respect to the hinge axis x circumferential line in the transition region from the first cone portion 19 in the second mouth portion 20 of the hinge pin 8, which transition line is in radial overlap to the conical surface of the thigh-side second cone portion 21. Der second cone section 21 extends beyond this transition line further in the direction of the outer side 18 with a final transition into the first mouth portion 22nd

Accordingly, a cross-sectional configuration of the free space 23 results, in which, starting from the outer side 18 over the axial height of the first mouth section 22, a region of constant radial dimension a results, which merges into a radially and axially continuously tapered interior Section. The result is a circumferential, inwardly directed gusset region of the free space 23. The radial dimension b of the bolt-side second mouth portion 20 can, as shown and also preferred, 1.2 to 1.8 times, further about 1.5 -Fun the radial dimension e in the region of the shaft portion 14 correspond.

This may result in an axial dimension f of the first cone portion 19 of the hinge pin 8, which is about 0.6 to 0.8 times, further about 0.7 times the axial dimension g of the total, from the first Coning portion 19 and the second mouth portion 20 composing head portion 13 may correspond.

Surrounding the hinge pin 8 results in the pliers legs ring wall areas. A first annular wall section 24 is assigned to the working areas 9 and 10 and, with reference to a cross section as shown in FIG. 9, extends between the annular free space 23 and the working areas 9 and 10.

A thickness h considered in radial extension to the joint axis x and along the axis of symmetry y corresponds in the illustrated embodiment to Approx tion approximately 0.5 times the radial dimension b of the bolt-side second mouth portion 20th

The first annular wall portion 24 in the direction of the axis of symmetry y opposite second annular wall portion 25 between the space 23 and the Ansetzbereichen the gripping arms 4 and 5 has a thickness k in this respect, which is about 1.5 times the bolt radial dimension b in Area of the second mouth portion 20 corresponds.

The hinge pin 8 is thus displaced approximately by the radial dimension e in the region of the shaft part 14 along the axis of symmetry y in the direction of the working areas 9, 10 from the geometric center of the crossing region of the pliers legs 2 and 3. This results in a favorable force introduction into the work areas 9 and 10 upon actuation of the forceps 1, this without affecting the hinge pin joint stability.

The above explanations serve to explain the inventions as a whole, which further develop the state of the art independently, at least by the following combinations of features, namely:

A pair of pliers, characterized in that the hinge pin 8 has a second mouth portion 20 which, starting from the outer side 18 of the pliers limb 2, 3 and perpendicular to a hinge axis x in

Cover to the first mouth portion 22, wherein the first and the second mouth portion 22, 20 define radially circumferentially between them an annular space 23, the radial dimension a the 0.05 to 0.15 times the measured from the joint axis x radial dimension B of the hinge pin 8 in the region of the second mouth portion 20 corresponds. A pair of pliers, characterized in that the first and / or second mouth portion 20, 22 in a cross section with the hinge axis x forms an acute angle.

A pair of pliers, which is characterized in that a measured in the direction of the hinge axis x length d of the second mouth portion 20 is greater than a measured in the direction of the hinge axis x length c of the first mouth portion 22nd

A pair of pliers, which is characterized in that the second mouth portion 20 is formed over a part of its axial length d in the radial opposite to a partial region of the second cone portion 21.

A pair of pliers, which is characterized in that the axial length d of the second mouth portion 20 corresponds to a 0.1 to 0.3 times the measured from the joint axis x radial dimension b of the hinge pin 8 in the region of the second mouth portion 20 , A pair of pliers, which is characterized in that the axial length c of the first mouth portion 22 corresponds to a 0.05 to 0.15 times the measured from the joint axis x radial dimension b of the hinge pin 8 in the region of the second mouth portion 20 ,

A pair of pliers, which is characterized in that both mouth sections 20, 22 merge into the same outer side 18 of the associated pliers limb 2, 3 or the hinge pin 8 extending at right angles to the articulation axis x. A pair of pliers, which is characterized in that the pliers 1 further comprises an axis of symmetry y passing through the hinge axis x, to which working areas 9, 10 of the pliers legs 2, 3 are movable towards each other.

A pair of pliers, which is characterized in that on the symmetry axis y a first annular wall portion 24 surrounding the working areas 9, 10, which surrounds the hinge pin 8, one half to one third of the radial dimension b of the hinge pin 8 in the region of second mouth portion 20 has corresponding thickness h.

A pair of pliers, which is characterized in that a second annular wall section 25 lying opposite the first annular wall section 24 in the direction of the axis of symmetry y has a thickness k approximately corresponding to the diameter of the hinge pin 8 in the region of the second mouth section 20.

All disclosed features are essential to the invention (individually, but also in combination with one another). The disclosure of the associated / attached priority documents (copy of the prior application) is hereby also incorporated in full in the disclosure of the application, also for the purpose of including features of these documents in claims of the present application. The subclaims characterize with their features independent inventive developments of the prior art, in particular to make on the basis of these claims divisional applications. List of reference numbers

1 pliers a Radialmaß

2 pliers legs b radial dimension

3 pliers legs c length

4 grip legs d length

5 grip legs e Radialmaß

6 jaw jaw axial dimension

7 jaw g Axial dimension

8 hinge pin h thickness

9 work area k thickness

10 Work area X Joint axis

11 Joint eye y Symmetry axis

12 joint eye

13 headboard

14 shaft part

15 riveting

16 bolt surface

17 blind hole

18 outside

19 first cone section

20 second mouth section

21 second cone section

22 first mouth section

23 free space

24 first ring wall section

25 second annular wall section

Claims

Pliers (1) with two crossed pliers legs (2, 3), wherein a fixed joint is formed, with a hinge pin (8), wherein the hinge pin (8) in any case associated with an outer side (18) of a pliers limb (2, 3) a further comprising the first cone portion (19) flaring towards the outside (18), the pliers leg (2, 3) further having an associated second cone portion (21) abutting the first cone portion (19) and into the outside (18) of the forceps limb (2, 3) emanating, first mouth portion (22), characterized in that the hinge pin (8) has a second mouth portion (20), starting from the outer side (18) of the forceps limb (2, 3 ) and is perpendicular to a hinge axis (x) in register with the first mouth portion (22), wherein the first and the second mouth portion (22, 20) radially enclose therebetween an annular clearance (23) whose Radial measure (a) corresponds to 0.05 to 0.15 times the measured from the joint axis (x) radial dimension (b) of the hinge pin (8) in the region of the second mouth portion (20).

Pliers according to claim 1, characterized in that the first and / or second mouth portion (20, 22) forms an acute angle in a cross section with the hinge axis (x).

Pliers according to one of the preceding claims, characterized in that in the direction of the hinge axis (x) measured length (d) of the second mouth portion (20) is greater than one in the direction of the hinge axis (x) measured length (c) of the first mouth portion

4. Pliers according to one of the preceding claims, characterized in that the second mouth portion (20) over a part of its axial length (d) is formed in a radial opposite position to a portion of the second cone portion (21). 5. Pliers according to one of the preceding claims, characterized in that the axial length (d) of the second mouth portion (20) is 0.1 to 0.3 times the measured from the joint axis (x) Radialmaßes (b) of Joint pin (8) in the region of the second mouth portion (20) corresponds, and / or, preferably, that the axial length (c) of the first mouth portion (22) 0.05 to 0.15 times the starting from the hinge axis ( x) measured radial dimension (b) of the hinge pin (8) in the region of the second mouth portion (20).

Pliers according to one of the preceding claims, characterized gekenn¬ shows that both mouth portions (20, 22) in the same at right angles to the hinge axis (x) extending outside (18) of the associated pliers limb (2, 3) and the hinge pin (8) merge.

7. Pliers according to one of the preceding claims, characterized in that the pliers (1) further comprises a through the hinge axis (x) going symmetry axis (y), on which work areas (9, 10) of the pliers legs (2, 3) are movable towards each other.

8. Pliers according to one of the preceding claims, characterized in that on the axis of symmetry (y) a the working areas (9, 10) associated first annular wall portion (24), which the hinge pin (8), one half to one third of the radial dimension (b) of the hinge pin (8) in the region of the second mouth portion (20) corresponding thickness (h).

Pliers according to one of the preceding claims, characterized in that a second annular wall section (25) opposite the first annular wall section (24) in the direction of the symmetry axis (y) has a thickness approximately corresponding to the diameter of the hinge pin (8) in the region of the second mouth section (20) (k).

Forceps characterized by one or more of the characterizing features of any one of the preceding claims.