EP1060841B1 - Self-adjusting pliers - Google Patents

Abstract

The pliers comprise two branches joined by a rod (15) having a female collar (1) which pivots on a pin (A) and guides a male collar (2) which slides inside and pivots on the male branch by means of a pin (B). A spring (3) sets the collars and a second spring (5) unites one (1) of the collars with the female branch. The male branch (6) has a head (7) having an upper toothed jaw (10) and a window (8) with teeth (9). The female branch (11) with a large opening allowing the passage of the male head carries a lower toothed jaw (13) and a toothed lug (14) which pivots on a spindle (21).

Description

The forceps which consist of two branches with toothed jaws and can slide between them by means of a pin element which enchased them and slides in a longitudinal window made in one of the toothed jaws, are well known.

In search of a better adaptation of the jaws to the piece to take in pincers and a maximum adhesion to it, a clamp where the branches are united posteriorly by a connecting rod which, under the pressure of one, at least, of its extremities , slide on one of the branches and allows the axis of the pin member to move, was developed by US Patents 4,651,598, 4,662,252, 4,922,770 and 5,020,399.

The sliding of the end of the rod makes it necessary to arrange on the (the) branch (s), grooves, channels, slides, orifices, to ensure this sliding and the establishment of the corresponding actuating springs on the connecting rod.

The need to have these grooves on the branches encourages, for ease of manufacture, to make branches based on superimposed steel plates, sandwich type, but this solution gives a clamp having little strength and a low durability. The second stage involved making the wrought iron branches, but keeping the grooves / holes poses machining and cost issues.

It is also noted that the stroke of the ends of the branches, until the jaws exert real pressure on the piece to be taken in pincers, was excessive.

The solicitor has solved all the problems mentioned by giving a simple and surprising answer: the pliers will be wrought iron, but the connecting rod will not slide, which automatically resolve the reported disadvantages.

• a).- Deux frettes qui se déplacent l'une par rapport à l'autre de façon télescopique, l'une d'entre elles pivotant sur la branche mâle et l'autre sur la branche femelle.
• b).- Un premier ressort d'enchâssement des deux frettes;
• c).- Un second ressort qui joint l'une des frettes à l'une des branches.

More concretely, the invention has a clamp where the connecting rod is composed of:

• a) .- Two frets which move relative to each other in a telescopic manner, one of them pivoting on the male branch and the other on the female branch.
• b) .- A first spring of embedding of the two frets;
• c) .- A second spring which joins one of the frets to one of the branches.

• La figure 1 est une vue en coupe partielle d'une réalisation pratique de la pince qui fait l'objet de l'invention, les mâchoires étant ouvertes.
• La figure 2 est une vue en coupe partielle d'une réalisation pratique de la pince de la figure 1, les mâchoires étant fermées.
• La figure 3 est une vue partielle de la section A:A de la figure 2.

To better understand the object of the present invention, there is shown, on the plans, a preferential form of practical realization susceptible of incidental changes that does not distort the basis.

• Figure 1 is a partial sectional view of a practical embodiment of the clamp which is the subject of the invention, the jaws being open.
• Figure 2 is a partial sectional view of a practical embodiment of the clamp of Figure 1, the jaws being closed.
• Figure 3 is a partial view of section A: A of Figure 2.

An exemplary practical, non-limiting embodiment of the present invention is described below.

The clamp is composed, as is known, of a male branch (6) having a head (7) to the upper toothed jaw (10) where has been made a window (8) with teeth (9) and a female branch (11) with large opening (12), which allows the passage of the head (7) of the male branch (6) and carrier of the jaw toothed (13) and a toothed pin element (14) which pivots on an axis (21) and engages with the teeth (9) of the window (8).

Being the essential object of the invention, the arrangement is such that the male branch (6) and the female branch (11) remain united by a connecting rod (15) which pivots at its ends on the male and female branches (6). , (11).

The connecting rod (15) consists of two elements that move relative to each other. In this embodiment, it is found that the connecting rod (15) consists of a female hoop (1) which pivots on a pin (A) on the female branch (11) and which serves as an external guide to a male hoop (2). which slides inside and pivots on the male branch (6) by means of a pin (B). The two frets (1), (2) are connected through a spring (3).

In the inner band (2) there is provided a stop pin (4) guided in a window (16) of the outer band (1), although it may be arranged in reverse, or provide the device with any other conventional means for limiting the stroke between the two frets (1), (2).

One of the two frets (1), (2) at least is under the action of a spring. In this case, a spring (5) connected to the outer hoop (1) and to the female branch (11) is pivotably mounted (C), its pivoting axis (C) being preferably located between the pin (A) of pivoting of the outer hoop (1) and the pivot axis (21) of the lug (14).

• a).- Lorsqu'il se déplace dans la fenêtre (8), il glisse sur les dents (9) de cette fenêtre (8).
• b).- L'enchâssement de ses dents (17) avec les dents (9) de la fenêtre (8) n'a lieu que lorsque l'extrémité (e) de sa tête (c) est en contact avec les dents (9), ce qui permet l'avancée de l'axe (21) de l'ergot (14) et l'enchâssement en résultant des dents (17) de l'ergot avec les dents (9) de la fenêtre (8).

Additional problems of the known clamps come from the pin (14), since:

• a) .- When it moves in the window (8), it slides on the teeth (9) of this window (8).
• b) .- The entrenchment of its teeth (17) with the teeth (9) of the window (8) takes place only when the end (e) of its head (c) is in contact with the teeth (9), which allows the advance of the pin (21) of the lug (14) and the ensuing resultant teeth (17) of the lug with the teeth (9) of the window ( 8).

In the invention, there is arranged in the window (8), close to the teeth (9), a sliding track (19) where slides a finger (18) protruding from the head (c) of the pin (14). ), so that the lug (14) is no longer in contact, when moving, with the teeth (19), and the pivoting of the lug (14) on its axis is as small as you want because it will depend on the separation (Δ) of the finger (18) with respect to the sliding track (19), thereby producing a more rapid and wear-free clamping of the lug (14).

This, coupled with the fact that the pivoting of the rod (15) from its rest position (α) or open clamp (Figure 1) to its closed clamp position (Figure 2) is very small (about 4 °), gives rise that the manual action (F) on the branches to clamp the workpiece (20) has a much lower stroke than was previously known.

Claims (3)

1. Self-adjusting pliers, of the type that have one upper and one lower arm with lockjaw and slipjoint with a catch that engages them and slides along a toothed window in one of the jaws, with both arms being joined by means of a rod, which is described as having the following features:

   a).- two bushes (1), (2) which telescope inside each other, with one pivoting (2) on the upper arm (6) and the other on the lower arm (11);

   b).- a primary spring (3) engaging both bushes (1), (2); and

   c).- a secondary spring (5) that connects one (1) of the bushes to one (11) of the arms.
2. Self-adjusting pliers, in accordance with the previous claim, with the feature of a limiter (4) restricting movement between the two bushes (1), (2).
3. Self-adjusting pliers, in accordance with claim number one, with the feature of a window (8) containing a guide (19) running lengthways along the wall for a finger (18) that protrudes from the head (c) of the catch element (14), establishing the existence of predetermined repairs (Δ) in the position of the open pliers between the aforementioned finger (18) and the slip guide (19).

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