FR2588125A1 - Clamp or vice for electrical connection to a conductor - Google Patents

Abstract

Branch-off clamp or vice for industrial electrical installations and networks, including, on the one hand, a metal body whose incurvate upper part constitutes a fixed jaw and, on the other hand, a movable jaw coupled to a drive screw engaged in a tapped hole at the base of the said metal body. According to the invention, the movable jaw is recessed (notched) on its lower face with a longitudinal groove capable of interacting with the end of the drive screw. This groove preferably has a dovetail-shaped profile and the end of the screw is a frustoconical journal of corresponding profile. This characteristic enables the movable jaw to be constituted by a single profile segment. On the other hand, the metal body has a guide rib parallel to the axis of the drive screw and capable of interacting with a recess (notch) made at the rear of the movable jaw. In order to enable the latter to engage laterally on the journal of the drive screw, the guide rib is interrupted, over a suitable length, and, after installing the said movable jaw, this gap is filled by an attached part, which is preferably constituted by an extension of a guide beak capable of being assembled onto the clamp body. The description relates more particularly to the application of the invention to a branch-off connector for overhead electrical networks as well as to various embodiment variants.

Description

The present invention relates to the field of connection means for electrical conductors of industrial networks and installations and more particularly for conductors of overhead distribution networks.

Many types of clamps are known which make it possible to establish, with an electrical conductor, a connection, either temporary, for example in order to carry out the grounding and short-circuiting of said conductor previously de-energized, or durable, for example to connect this conductor, then called main, to a derivative conductor. In the most usual form, these clamps are formed of a body of which a part constitutes the fixed jaw, said body carrying a tapped hole in which is engaged a control screw subject to a movable jaw capable of moving parallel to the fixed jaw and cooperate with those to ensure the clamping of the conductor.

When the clamp is intended to be placed on conductors using an insulating pole, the head of the control screw has a shape allowing it to be temporarily adapted to such a pole; when it is intended to be placed by hand, the control screw is most often traversed by a transverse rod forming a handle and making it possible to apply a suitable tightening or loosening torque, the clamp is then usually designated under the vice name.

The movable clamping jaw must be coupled to the control screw by a mechanical means which does not hinder the free rotation of those. To this end, numerous embodiments are known which use, for example, a screw, a pin, a rivet, etc. The assembly of these retaining means represents a non-negligible labor cost, moreover their mechanical strength is often limited, so that if the operator continues to act on the screw in the direction of loosening when the jaw has reached the fully open position, it risks separating from the jaw; the clamp is then out of use.

On the other hand, in the most general case where the posterior wall of the orifice of the gripper body has a flat face against which the movable jaw can move, which necessarily has a certain clearance relative to this flat face, andwhen the conductor to be clamped between the jaws is of small cross section, it sometimes happens that this conductor gets caught between the movable jaw and the clamp body and this results in a blockage of the mechanism and poor electrical contact.

The present invention relates to a bypass clamp or vice which entirely eliminates the drawbacks and weaknesses mentioned above. It is characterized in particular by the fact that the end of the commarr screw is engaged in a groove for example in dovetail profile running over the entire underside of the movable jaw, which makes it possible to execute this at from a profile which it suffices to cut to the desired length. The end of the control screw is shaped, by vexing ple by bar turning or stamping, to form a trunnion whose profile corresponds to that of the groove, so that the assembly of these two elements can be carried out by simple introduction of the pin into the groove, without the addition of any retaining piece-According to a preferred embodiment, the invention provides that the rear wall of the opening of the clamp body has a rib parallel to the axis of the control screw and that a notch made in the corresponding face of the movable jaw can engage on this rib, which has the effect of d on the one hand to guide c this jaw in its longitudinal movements, on the other hand to prevent it from escaping laterally. Furthermore, the presence of this rib prevents the accidental jamming of a conductor of small cross section between the movable jaw and the clamp body .

In order to allow engagement of the movable jaw by sliding the teral on the trunnion of the control screw, the guide rib is interrupted over a length substantially equal to the height of said jaw. There could therefore be a risk when, during its unfolding, this jaw is found at the level where it is no longer held by the rib, of seeing it escape laterally. This is why the invention also provides that the clamp body is arranged to receive an insert, the profile of which is connected to that of this rib and which links it in the zone where it is interrupted. Once this part is in place, it becomes impossible, even voluntarily, to extract the movable jaw. According to the invention, this part can be constituted by a combination of a guide spout assembled on the clamp body in view to facilitate the engagement of a driver. This spout being outside the area susceptible to being traversed by electric currents, can be executed in a molded dielectric material, which allows a saving of cost and mass.

According to other embodiments, the invention also provides that instead of a guide rib cooperating with a notch in the movable jaw, a guide groove could be produced cooperating with a projecting part of the movable jaw or else that one could dispc ser behind the opening of the gripper body two lateral guide ribs cooperating with two projecting parts disposed at the ends of the movable jaw and oriented towards the rear.

The invention will be better understood by referring to the attached drawings and the description which follows, which have been limited by way of example to the production of a branch connector for overhead electrical networks, the man of loom being capable without problem of transposing the characteristics described to the execution of all kinds of clamps or vises, such, among others, as those intended for the earthing and in short waxed conductors.

In these drawings, Figure 1 shows a left profile view of a connector according to the invention, without its guide beak.

Figure 2 shows the same connector seen from the front.

FIG. 3 represents a left side view in partial section of the detail of the coupling of the movable jaw on the control screw.

Figure 4 shows a plan view of the movable jaw engaged on a guide rib.

FIG. 5 represents a perspective view of the guide spout intended to be fixed on the clamp body and of its extension intended to connect to the rib in the area where this is interrupted.

FIG. 6 represents the rear wall of the opening of the clamp body notched by a guide groove constituting another embodiment.

FIG. 7 represents a plan view of the modified movable jaw in this other embodiment.

Figure 8 shows a plan view of the modified movable jaw in a third embodiment.

According to FIGS. 1 and 2, the connector essentially consists, on the one hand, of a metal body 1, on the other hand, of a mechanical assembly 2 comprising a control screw 21 coupled to a movable jaw 22.

The body 1 has a forward opening 10 provided for receiving the main conductor to be clamped 3 and delimited upwards by a curved part 101 constituting the fixed clamping jaw for the conductor 3, downwards by a plate 102 under which is disposed a boss 102.1 pierced with a tapped hole in which is engaged the control screw 21, at the bottom by a wall 103 whose plane is prallel to the axis of the screw 21 and which has a projecting guide rib 104- occupying most of its height, but which is interrupted in a zone 105. This wall 103 is framed between two ribs 106. At the rear of said wall there is a connection assembly of a derivative conductor 4 which constitutes a usual embodiment zone this derivative conductor is introduced into a cavity 107 through a sealing cover 108 and is tightened under a screw 109. Finally, the curved part of the body 101 is extended forward by a stud 110 provided for receive the beak guide 5 described later.

The movable jaw 22 is preferably made from a section section cut to the desired length, its upper face has a shallow groove 221 making it possible to ensure good tightening of the main conductor 3, its lower face is hollowed out of a groove 222 in dovetail profile. Finally, on its rear face, the jaw 22 is hollowed out by a notch 223 whose shape and dimensions correspond to those of the guide rib 104 with which it is called upon to cooperate.

In order to achieve the coupling of the jaw 22 on the screw 21, the end of those is shaped to form a pin 211 whose shape and dimensions correspond to the profile of the groove 222 so that said pin can be introduced into said groove at one of its extra 'mites and that it is therefore retained there but with sufficient play so that the screw 21 can rotate freely.

The head of the control screw 21 has a shape allowing it to temporarily adapt to the end of the pole using which the connector must be worn on the main conductor - for example a ring 212 compatible with the poles hooks commonly used for performing live work.

To proceed with the assembly, the screw 21 is engaged in the tapped hole of the boss 102.1 and screwed up to the point where the pin 211 reaches the level of the zone 105 in which the rib 104 is interrupted. In this zone, no obstacle prevents the jaw 22 from being inserted laterally in order to cause the pin 211 to penetrate into the groove 222.

When the screw 21 is then loosened, the movable jaw 22, in any position it can occupy, is prevented from escaping laterally by the combination of the rib 104 and the notch 223 The risk of escaping cannot be present that when the jaw 22 is brought back to the level of the zone 105 in which the rib 104 is interrupted. This is why the invention provides for filling this void with an insert 53 extending and relaying this rib 104. According to a preferred embodiment, this insert is an appendage to a guide spout 5 intended to facilitate the remote introduction of the main conductor 3 between the jaws 101 and 22 and preferably performed in molded dielectric material. To this end, the spout 5 has a mortise 51 whose shape and dimensions correspond to those of the stud 110 on which it can be assembled by gluing or by an appropriate mechanical means. Towards the rear, the spout 5 is extended by 2 legs 52 carrying at their end the insert 53. The legs 52 take place in grooves made in the upper part of the opening 10, not shown so as not to harm the readability of the figures, so that said tabs 52 do not have protrusions in this opening which would harm electrical contact with the conductor 3, the only protruding part being the part 53 dnas the only measure necessary to ensure the continuity of the rib 104.

According to another embodiment shown in Figures 6 and 7, the wall 103, instead of having a projecting rib, is notched along its longitudinal axis by a guide groove 107 while the movable jaw 22 carries at the rear , in the middle a lug 224 of shape and dimensions corresponding to those of said groove with which it cooperates to provide longitudinal guidance and lateral support of said movable jaw. In order to allow the assembly of this jaw on the pin 211 by lateral sliding, the wall 103 is further notched over its half-width by another groove 108 perpendicular to the groove 107. To assemble, the screw 21 is engaged in the threaded hole of the boss 103 and screwed up to the point where the pin 211 reaches slightly below the groove 108. The lug 224 is then introduced into this groove, the jaw 22 is pushed laterally and in this movement the pin 211 engages in the groove 222. In its final position, the lug 224 is in the extension of the groove 107. Eh then unscrewing the screw 21, it causes the descent of the jaw 22, held laterally by the conjunction of the lug 224 and the groove 107. The lateral escape of the jaw would only be possible when this lug is found at the level of the groove 108. The invention provides for avoiding the risk by obstructing this groove with a mechanical obstacle e, for example a splined pin 109.

According to a third embodiment represented by FIG. 8, the longitudinal guidance and the lateral support of the movable jaw 22 are ensured by the ribs 106 framing the wall 103, ribs which are parallel to the axis of the screw 21. At this Indeed, the jaw 22 can be provided on its rear face with two projecting parts capable of sliding against two faces of these ribs. These parts can simply be fluted pins 225 with a sufficiently large head capable of being locked in two holes 226 open in the rear face of the jaw 22.

To proceed with the assembly, the screw 21 is engaged in the tapped hole of the boss 103 and screwed a few turns so that it is possible to penetrate the pin 211 in the groove 222 to the middle of the length of the jaw 22. The two pins 225 are then forced into the two holes 226, which prevents any lateral escape from the jaw.

Of course these examples of application of the invention to a branch connector are in no way limiting and it would not go beyond the scope of the invention to transpose them to parts or instruments of all kinds in which the problem of tightening arises an electrical conductor under the pressure of a movable jaw actuated by a screw.

Claims (9)

1 - Clamp or bypass vice intended to establish a connection with a  electrical conductor 3 by clamping it between two jaws  control screw 21.  gitudinal 222 capable of cooperating with the end 211 of the  face opposite to the fixed jaw, is notched by a groove lon  it is in that said movable jaw 22, on its  the action of a control screw 21 engaged in a tapped hole,  22 capable of moving parallel to the fixed jaw under  apex constitutes a fixed jaw, on the other hand a movable jaw  lique 1 having in its front face an opening 10 whose  22 - 101 and essentially comprising, on the one hand, a metal body 2 - Clamp or bypass vice according to claim 1, characterized in  that said groove 222 of the movable jaw 22 has a pro  dovetail-shaped wire and in that the end of the screw  command is a tapered journal 211 whose profile corresponds  to that of said dovetail. 3 - Clamp or bypass vice according to claim 1-, characterized in  what the rear wall 103 of said opening 10 of the body  metal frame 1 has at least one guide rib 104 parallel to  the axis of said control screw and in that said movable jaw  has a notch 223 capable of being engaged on said ner  guide vure. 4 - Clamp or bypass vice according to claims 1 and 3, charac  terized in that said guide rib is interrupted on a  part 105 of the height of said opening. 5 - Clamp or bypass vice according to claims 1, 3 and 4, ca  characterized in that the part of said metallic body 1 in which  said guide rib 104 is interrupted is arranged so  to receive an added part 53 whose profile extends that of  said rib. 6 - Clamp or bypass vice according to claim 1, characterized in  that said movable jaw 22 is formed of a profile segment. 7 - Clamp or bypass vice according to claim 1, characterized in  what the rear wall 103 of said opening 10 has at  at least one guide groove 107 parallel to the axis of said screw  control 21 and in that said movable jaw 22 presents towards  The rear a protruding part 224 capable of being engaged in said  guide groove. 8 - Clamp or bypass vice according to claim 1, characterized in  that said opening 10 of the metallic body is delimited in its part  posterior by two lateral guide ribs 106, parallel to the axis  of said control screw and in that said movable jaw has at  its ends two projecting parts 225 capable of sliding the  along said guide ribs. 9 - Clamp or bypass vice according to claims 1,3, 4 and 5, charac  terized in that the insert 53 extending said rib is  integral with a guide spout 5 capable of being assembled on the body  of pliers.