WO2009141466A1

WO2009141466A1 - Ergonomic locking pliers

Info

Publication number: WO2009141466A1
Application number: PCT/ES2009/000133
Authority: WO
Inventors: José Antonio IRIONDO GAZTAÑAGA
Original assignee: Grip-On Tools, S.A.
Priority date: 2008-05-19
Filing date: 2009-03-10
Publication date: 2009-11-26
Also published as: ES1067998Y; ES1067998U

Abstract

The invention relates to a pliers having a stationary lower jaw (1) and a moving upper jaw (2), connected to a respective stationary lower handle (3) and moving upper handle (4). The lower handle (3) forms an angle with the lower jaw (1). The jaws (1 and 2) are positioned in relation to the handles (3 and 4) such that, when gripped by the user, the third metacarpal bone of the hand and the radius of the forearm are aligned in the same direction as the jaws (1 and 2), thereby enabling the power of the exerted force to be increased and pliers handling comfort to be improved. A locking rod (7) is hinged between the jaws (3 and 4) and the length of the rod can be adjusted by manually actuating a nut or element (8). The pliers can be unlocked by manually actuating a cam (11) provided on the upper part of the handle (4). Both the element or nut (8) and the cam can be actuated by the hand holding the pliers. The pliers is maintained locked by means of a quadrilateral formed between the hinged connection points (17-5-10-9), hinges 17 and 5 corresponding to the hinges between the upper jaw (2) and the lower jaw (1) and upper handle (4) and hinges 10 and 9 corresponding to the hinges between the locking rod (7) and the handles (3 and 4).

Description

ERGONOMIC TENZA LOCK OBJECT OF THE INVENTION

The present invention, as expressed in the statement of this respective report, refers to an ergonomic locking pliers, which has been conceived and realized as a manual tool for handling a wide variety of elements.

The object of the invention is to facilitate the handling of the pliers due to a special ergonomic configuration thereof, involving less effort and greater comfort in handling.

BACKGROUND OF THE INVENTION

The so-called locking pliers are known for performing certain manual works, there being a great variety of models based, all of them, on the mechanical properties provided by an articulated quadrilateral and established in the pincer itself, a quadrilateral formed by the articulations of its two mouths between yes and with their corresponding handles, in combination with the connecting rod joints.

Well, in all known locking pliers the blocking situation that allows the pliers to be kept in their closed position and therefore tightening once this position is reached, is achieved when they are aligned, three joints turning the quadrilateral into a triangle.

The shape of the quadrilateral varies with the thickness of the object that is caught between its mouths. The mouths are immobilized when you squeeze an object or collide with each other. Therefore, to achieve the blockage, it is necessary to vary the size of one of its sides. This is done by modifying the position of the support point of a fixed-length connecting rod, or by varying the length of the connecting rod itself.

In the known tongs the mouth considered superior extends into the respective grip, forming an element that turns out to be fixed with respect to the remaining elements of the pliers, this comprising the corresponding lower mouth that moves based on the articulated quadrilateral between said movable mouth, the hinge articulated to it, the upper mouth and fixed with its respective handle, and an articulated element between both handles to establish the locking position. The configuration of the described pliers means that to obtain the blocking position, an effort must be made with the outer phalanges of the fingers, on the handle of the movable mouth, which means fatigue for said fingers.

In addition, due to the configuration of the pliers, in the effort that is made to reach the blocking position, the wrist is located with a small angulation with respect to the forearm, that is, the position of the hand is ergonomically incorrect, which entails that the greatest effort is limited to that which can be done exclusively with the fingers, without being able to help with the strength of the rest of the forearm, there is even the risk of a wrist injury due to an incorrect and forced position of the wrist.

In addition, in conventional pliers it is necessary to use, one hand to hold the tool and the other well to release the locking position (unlock) and / or to regulate the opening of the pliers and would adjust the thickness of the work objects.

DESCRIPTION OF THE INVENTION

The invention consists of an ergonomic locking pliers, with particular characteristics on the basis of which the problems and problems set forth above are solved.

In this sense, a first characteristic of novelty of the pliers is that the lower mouth is the one that remains fixed and extends in its corresponding grip, so that the positioning of the tips of the mouths with with respect to the handle, they form an angled position such that the third metacarpal bone of the hand and the radius of the forearm are aligned in the same direction of the mouths, thus creating an ergonomic design to ensure that the locking and actuation of the pliers are carried out in an anatomical position of maximum comfort.

Another characteristic of novelty is that a connecting rod of variable length (as an adjustment and locking element) articulated between the handle of the lower mouth and the handle of the upper mouth has been designed, thereby allowing the regulating nut to be operated directly with the thumb of the grip hand always keeping the same distance from the finger, keeping the second hand free. Another characteristic of the pliers is the provision of a cam by means of which the unlocking of the quadrilateral takes place, a cam that is located inside the rear handle and whose thrust end comes out from the top of the said handle, thus achieving to unlock the pliers by means of the use of a single hand, for this it will be enough to push said unlocking cam with the thumb of the hand that holds the clamp.

Another characteristic of novelty is that in the case of the invention, the mobile grip is posterior and receives the thrust with the palm of the hand while the phalanges serve as a support point, allowing all the force that the forearm can provide without risk be used. of injury when the wrist bones are perfectly aligned with the forearm. On the contrary, in the conventional pliers in which the mobile grip is anterior, it is operated with the phalanges, the wrist is distorted and transmits the effort worse.

Another characteristic of novelty is that the pliers are equipped with a bridge where the movable mouth is housed. Said bridge gives the mobile mouth a housing - A - and guided by it, achieving an increase in stiffness because the bridge prevents gaps in the lateral stresses to which the movable mouth can be found. A spring between the movable mouth and the front handle facilitates the unlocking or opening, being such a pincer materialized preferably in treated steel, and in which the previous handle has a rubber sheath preventing oxidation and always keeping the tool in good condition, at the time that the user feels an optimal softness in the grip. Also, both handles have a configuration that provides an increase in the ergonomics of use of the tool. For this, the anterior grip has a concave shape that facilitates the grip of the fingers therein, while the posterior grip has a convex configuration so that it fits better in the palm of the hand.

BRIEF DESCRIPTION OF THE DRAWINGS To complement the description to be made and in order to help a better understanding of the features of the invention, this descriptive report is attached to a set of drawings based on which they will be more easily understood the innovations and advantages of the ergonomic locking pliers made in accordance with the object of the invention.

Figure 1.- It is a side view of the pincer of the invention in the locked position, a hand having been represented by operating said pincer.

Figure 2.- It is a side view of the same pincer, in this case in the open position.

Figure 3.- Shows a profile view of the pliers corresponding to figure 1.

Figure 4.- Shows a sectional view corresponding to the line of cut AA represented in figure 3. PREFERRED EMBODIMENT OF THE INVENTION

As can be seen in the aforementioned figures, the pincer of the invention comprises a lower mouth 1, an upper mouth 2 articulated in 17 to a bridge 14 solidly connected to the lower mouth 1, an anterior handle 3 forming a single piece body with the mouth lower 1, also forming an angulation with it, and a rear handle 4 articulated in 5, to the upper mouth 2, whereby the latter is considered as a movable mouth and articulated in 10 to a connecting rod 7, which comprises a threaded spindle 15 , a nut 8 and a cylinder 16, which is articulated to the front handle 3 in 9 and the rear handle in 10. Between the upper mouth 2 and the front handle 3 there is provided a spring 6 whose function is to facilitate unlocking. Said connecting rod 7 constitutes the means that keeps the mouth in a locked or tightened position, once the closed position has been reached and that corresponds to the alignment of the articulations 9 and 10 of such connecting rod 7 with the articulation 5 of the rear handle 4, as shown in figures 1 and 4.

As can be seen in the figures, the anterior handle 3 is fixed and extends downwards to establish the ergonomic configuration of the assembly.

The actuation of the pliers to achieve the closed or locked position represented in figures 1 and 4, is carried out by hand 13, placing the fingers on the front handle 3, while the force exerted by the forearm at hand 13 is transmits to the rear handle 4, causing it to swing in approximation towards the previous handle 3, so that by virtue of the quadrilateral formed by the two handles 3 and 4, the connecting rod 7 and the joints 5 and 10, makes said connecting rod 7 align with the last two articulated joints 5 and 10, establishing the pincer block. The quadrilateral of joints 17-5-10-9 (figure 2) when becoming the triangle 17-5-9 (figure 1) causes the blockage to occur.

In the case of wanting to carry out the unlocking, it will be enough to push on a supero-posterior cam 11 of the rear handle 4, swinging it and establishing the misalignment of the joint 10 of the connecting rod 7 out of the line between the joints 5 and 9 , thereby achieving the opening of the pliers as seen in Figure 2, collaborating in this unlocking or opening the spring 6 that pulls from the back of the upper and mobile mouth 2. Said unlocking occurs by operating with the thumb of the hand 13 that handles the pliers, without using the other hand by the user.

The bridge 14, solidly connected to the lower body 3, serves as an articulation and accommodation to the movable mouth 2 and facilitates its guidance. In addition, said bridge 14 avoids the gaps that can occur due to large lateral forces of the movable mouth 2 itself in the work, thus contributing rigidity to the tool. As it has already been said, the opening can be regulated by actuating the nut 8, this drive being able to be carried out directly with the thumb of the hand 13 that handles the pliers, without using the other hand of the user. Finally, say that the pliers are made of treated steel and the handle 3 equipped with a textured rubber sheath 12 (Figure 4) for greater comfort of the fingers.

Claims

1, - ERGONOMIC LOCK TENAZA, which being of the type of which in its closed position produces a block that is maintained by itself based on an articulated quadrilateral (17) - (5) - (10) - (9) established between the two mouths (1-2), their corresponding handles (3-4) and a connecting rod (7) articulated between said two handles, as an element that maintains the lock itself, is characterized in that the lower mouth (1), its corresponding fixed front handle (3) and the bridge (14) form a unique and fixed body with an angulation between the lower mouth (1) and its corresponding handle (3), with the handle projected downwards, the direction of the mouth (1) the same as that of the arm that holds the pliers, while the upper mouth (2) is mobile and articulated in (17) with the fixed mouth (1) and in (5) with its corresponding movable rear handle (4), with the particularity that the joints (17 and 5) and the joints (9 and 10) of l The connecting rod (7) to the movable rear handle (4) and the fixed front handle (3) determine the corresponding articulated quadrilateral in which the alignment of the joints (9, 10 and 5) establishes the blocking position of the pliers by the connecting rod (7).

2.- ERGONOMIC LOCK TENAZA, according to claim 1, characterized in that the blocking rod (7) has a hand operated element (8) for regulating the opening of the pincer itself, conveniently accessible to the thumb of the same hand (13) that handles such pincer.

3.- ERGONOMIC LOCK TENAZA, according to previous claims, characterized in that the handle (3) incorporates a rubber sheath (12).

4.- ERGONOMIC LOCK TENAZA, according to previous claims, characterized in that it is preferably materialized in treated steel.

5.- ERGONOMIC LOCK TENAZA, according to previous claims, characterized in that the central area is provided with a bridge (14) for articulation, accommodation and guidance of the movable mouth (2), providing rigidity to it.

6.- ERGONOMIC LOCK TENAZA, according to previous claims, characterized in that the anterior handle (3) is concave, while the rear handle (4) is convex, for the correct adaptation of the hand in the grip of the pincer itself.

7.- ERGONOMIC LOCK TENAZA, according to previous claims, characterized in that in the upper part of the rear handle (4) an unlocking cam (11) is provided whose drive end is projected towards the outside of it, which is operable by the same hand (13) that grips the pliers.