FR2843496A1 - Exterior cable junction box connection having isolating box with spring strip loop having free end tool positioned active cable position and tool clamped during operation - Google Patents

Abstract

The cable connection unit has an isolating box (2) with an inner conductor slab (5). There is a spring strip loop (6) with a moving section (16). An electrical cable (11) can be introduced through a window (10). The moving spring strip section holds the cable in place. The window has a blocking mechanism (35) to hold the spring strip activating mechanism (13) in place when the tool is introduced.

Description

The present invention relates to an electrical terminal block for

  connection of electrically conductive elements

outside the block.

  The invention relates more particularly to a terminal block comprising: - an insulating housing, - at least one conductive bar housed in the housing, - at least one loop spring leaf which is housed in the housing, which comprises a first branch placed in electrical contact with the conducting strip, and a second movable branch provided with an opening intended for the passage of the end of an electrical cable, - at least one window for introducing electrical cable formed in one face of the housing and which opens out in the vicinity of the movable branch, - and at least one operating window for the spring leaf provided

  in one face of the housing and intended for the passage of an external tool for moving the movable branch of the spring blade between a rest position in which the position of the opening is not marked with respect to the insertion window, and an active position in which the leaf spring 20 is constrained and the opening is opposite the introduction window.

  After being introduced into the operating window to crush the spring loop, the external tool such as a screwdriver tends to be pushed out of this window. The spring loop in fact exerts a force on the rod of the screwdriver, the direction of which is opposite to the direction of insertion of the screwdriver. It is then necessary for the operator to hold this screwdriver in place until he has put the end in place

  an electric cable in the block.

  It is therefore understood that the operator must use his two hands only for the connection of the cable whereas during this connection operation, it is often necessary to have a free hand for a

parallel action.

  The present invention aims in particular to provide a new electrical terminal block which overcomes the aforementioned drawbacks

  and this, by simple, effective and inexpensive means.

  To this end, according to the invention, an electrical junction block of the kind in question is essentially characterized in that the operating window comprises locking means for temporarily blocking the external tool in the operating window when this tool is inserted.

  to move the leaf spring to the active position.

  Thanks to these provisions, the connection of an electrical cable 5 in the electrical terminal block requires only one hand of the operator. The latter thus has a free hand for another simultaneous task. Advantageously, the blocking means comprise

  first elastic return means which urge the external tool in the same direction as the urging of the leaf spring on the external tool.

  Preferably, the locking means comprise second elastic return means which urge the external tool in a direction transverse to that of the urging of the leaf spring on

the outside tool.

  More preferably still, the first and / or second elastic return means urge the external tool against a wall of the

maneuvering window.

  Advantageously, the first and / or second means of

  reminder extend over substantially the entire height of the operating window and protrude inside thereof.

  In a preferred form, the first and / or second return means comprise at least one convex tab whose convexity is

  facing the inside of the operating window.

  Preferably, the tab extends over the entire width of the operating window 25.

  Advantageously also, the first and / or second return means comprise at least two teeth which project inwards

of the maneuver window.

  Preferably, the first and / or second return means comprise two convex tabs, the convexity of which is turned towards the inside of the operating window and which protrude in the corners

of it.

  Other characteristics and advantages of the invention

  will appear during the following description of five of its embodiments, given by way of nonlimiting example, with reference to the drawings

  joints, in which: - Figure 1 is a partial side view of a first embodiment of a terminal block according to the present invention, the upper face of the block being seen in section; - Figure 2 is a top view of only windows 5 for cable introduction and operation of an external tool from the block of Figure 1; and - Figures 3 to 6 are views similar to that of Figure 2, respectively of the second to fifth embodiments

  of the block according to the present invention.

  In Figure 1 is shown an electrical terminal block 1 for the connection of electrical cables outside the block. In a manner known per se, this terminal block comprises a housing 2 made of a molded insulating material, the general appearance of which is flat and of small thickness relative to its other dimensions. This box has a fixing foot 15 which allows it to be fixed on a support rail of a standardized type with other identical or compatible boxes against or between

  which it is planned to place.

  In the embodiment shown and according to a known technique, the housing 2 is in the form of a box, the bottom 4 of which, also called the side face, supports various housings which are specifically formed to receive in particular a conductive bar 5 and blades

loop spring 6.

  The side face 4 plays the role of a side wall of separation vis-à-vis another identical or compatible box, when two terminal blocks are mounted side by side on the same support rail. The box 2 is here supposed to be closed by an external element forming a partition which comes to constitute a second side wall parallel to the

first side face 4.

  In a manner still known, the conductive strip 5 is preferably made of a rigid electrically conductive flat material, and has legs 7 intended to come into electrical contact with the

loop springs 6.

  Each of the loop springs 6 are placed in

  housings 8 which are carried by the side wall 4 of the housing 2.

  The upper face 9 of the housing 2 opposite the foot 3 of this housing has, at each housing 8, an introduction window 10 of an electric cable 1 1, and an operating window 12

  an external tool such as a screwdriver 1 3.

  In a manner still known, each loop spring 6 is formed from an elastic blade, for example made of stainless steel. This elastic blade 5 is folded back so as to form a spring. It then has a form of loop comprising a support branch 15 and a branch

mobile 1 6.

  The support branch 15 is intended to come to rest against the

  leg 7 of the bus bar 5.

  The movable branch 16 has a bent shape, the elbow 17 of which is substantially situated vertically from the window of

operation 12.

  The movable branch 16 still has an opening in

  which is intended to penetrate the electric cable 11 to come into contact with the leg 7 of the conductive strip 5.

  The housing 8 in which the leaf spring 6 is received, has a side wall 20 located opposite the elbow 17 of the movable branch 16 of the blade 6, this side wall is oriented obliquely, in the direction of the leaf spring and extends by a straight partition 21 extending 20 substantially perpendicular to the upper face 9 of the housing 2. The housing 8 also has a bottom 22 which extends parallel to the face

upper 9 of said housing.

  In the rest position of the spring loop 6 as shown in the left part of FIG. 1, the opening formed in the movable branch 16 of the spring loop 6 occupies a rest position in which the position of the opening does not is not spotted in relation to the

  insertion window 10 of the electric cable 1 1.

  On the contrary, and in a manner known per se, in the constrained position of the spring loop 6 as shown on the right-hand part 30 of FIG. 1, the opening carried by the movable branch 16 is situated vertically from the window d introduction 10 so that the stripped end 28 of the electric cable 11 can penetrate through this opening to be pressed by the spring against the tab 7 of the bar

driver 5.

  As is more particularly visible in FIG. 2, the operating window 12 is for example of rectangular shape. This window extends in the direction of the upper face 9 to have two long sides 30, 31 and two short sides 32, 33. The two long sides 30 and 31 extend parallel to the side face 4 of the housing 2

  while the two short sides 32 and 33 are transverse.

  To move the leaf spring 6 between its rest and active positions, an external tool such as a screwdriver 13 is engaged in the operating window 12 in order to come into contact with the oblique side wall 20 of the housing 8 and thus come to bear against the

  elbow 17 of the movable branch 16 of the spring.

  In a second step, the screwdriver being engaged until it abuts against the bottom 22 of the housing 8, the screwdriver crushes the loop spring 6 so that the movable branch 16 is moved to its active position in which its opening is located below the insertion window 10 of the electrical cable 1 1. During the operation of the spring 15, the screwdriver thus passes from an inclined position in which it bears on the one hand against the short side 33 of the operating window 12 and on the other hand, against the oblique side wall 20, to a vertical position in which the free end of the screwdriver is in

  support against the right wall 21 of the housing 8.

  According to an essential characteristic of the invention, the operating window 12 has locking means 35 making it possible to temporarily block the screwdriver 13 in the operating window 12 when this screwdriver has been inserted to the bottom of the housing 8 for

  move the leaf spring 6 to its active position.

  The locking means 35 are elastic return means which deform during the introduction of the screwdriver 13 into the operating window 12 and which urge the screwdriver rod 13 against one of the sides of the window to wedge the screwdriver 13 when the latter is in position in the housing 8. In this position, the screwdriver is substantially straight and bears on one side against the right partition of the

  housing 8 and on the other side, against the elbow 17 of the spring loop 6.

  The locking means 35 exert sufficient friction forces, for example by wedge effect, on the rod of the screwdriver to block the screwdriver in the opening. These forces are sufficient in the sense that they are at least equal to the force exerted by the spring loop 6 on the rod of the screwdriver and which tend to bring it out of the operating window. In a first embodiment shown in

  Figure 2, the return means 35 take the form of a convex tab 5 whose convexity is turned towards the inside of the operating window 12. This tab 36 extends over the entire width (parallel to the short side 33 ) of the operating window 12 and over the entire height thereof as can be seen in FIG. 1. It is thus secured to the bottom of the operating window as well as to the long sides 30 and 31 of this window.

  In practice, the convex tab 36 has come integrally with the

  upper face 9 of the housing 2 being constituted by a thin veil.

  Preferably, this convex tab 36 is located on the short side 33 of the operating opening 12 which is opposite the oblique lateral wall 15 of the housing 8. This tab is located under the screwdriver when the latter is inclined to be introduced into the housing 8. When introducing the screwdriver, the convex tab 36 is elastically deformed by the rod. The convex tab 36 then biases the screwdriver 13 towards the opposite small side 32, that is to say, in the same direction as the biasing force exerted by the spring on the end of the screwdriver. The screwdriver shank is therefore wedged between the convex tab 36 and the opposite small side 32 and cannot come out of

  the operating opening under the effect of the spring loop 6.

  In a second embodiment, the return means 35 take the form of two teeth 38 which project from the short side 33 towards the opposite short side 32. In the same way as the convex tab 36, the two teeth 38 press on screwdriver 13

  to lock it in position in the operating opening 12.

  In yet a third embodiment such as that shown in FIG. 4, the locking means 35 take the form of

  two convex tabs 39 and 40, the convexity of each of which faces the interior of the window. They extend along the long sides 30 and 31 of the operating window 12. These two tabs 39 and 40 thus bias the screwdriver in a direction transverse to that of the force exerted by the spring on the screwdriver.

  In Figure 5 is shown a fourth embodiment of the locking means 35. These take the form of three lugs 42 to 44 which each extend from one side of the window

  operation 12 to resiliently lock the screwdriver 13.

  Finally, in a fifth embodiment shown in FIG. 6, the locking means 35 take the form of two convex tabs 45 and 46 extending in the angles between the large

  sides 30, 31 and the short side 33 of the operating opening 12.

  It is understood that the locking means according to the present invention advantageously make it possible to block the screwdriver 13 when the latter has deformed the leaf spring 6 and thus free the hands of the operator so that he can easily introduce the cable 11 in the

  introduction window 10 while keeping one hand free.

  It goes without saying that the invention is not limited to the preferred embodiments described above by way of nonlimiting example; on the contrary, it embraces all the variant embodiments in the

The scope of the claims below.

Claims (9)

  1. Electric terminal block for the connection of external electric cables to the block comprising - an insulating box (2), - at least one conductive bar (5) housed in the case (2), - at least one leaf spring in a loop ( 6) which is housed in the housing (2), which comprises a first branch (15) placed in electrical contact with the conductive strip (5), and a second movable branch (16) 10 provided with an opening intended for the passage of the end of an electric cable (11), at least one introduction window (10) of electric cable (11) formed in one face (9) of the housing (2) and which opens in the vicinity of the movable branch ( 16), - and at least one operating window (12) of the leaf spring (6) formed in one face of the housing (9) and intended for the passage of an external tool (13) to move the movable branch (16) of the leaf spring (6) between a rest position in which the position of the opening is not identified by relative to the introduction window (10), and an active position in which the leaf spring (6) is constrained and the opening is opposite the introduction window (10),   characterized in that the operating window (12) comprises locking means (35) for temporarily locking the external tool (13) in the operating window (12) when this tool is inserted to move the leaf spring (6 ) in active position.   2. Terminal block according to claim 1, characterized in   that the locking means (35) comprise first elastic return means (36; 38; 44; 45, 46) which urge the external tool (13) in the same direction as the urging of the leaf spring (6) on the external tool (13).   3. Terminal block according to claim 1 or 2, characterized in   that the blocking means (35) comprise second elastic return means (39, 40; 42, 43) which urge the external tool (13) in a direction transverse to that of the stress on the leaf 35 (6 ) on the external tool (13).   4. Terminal block according to claim 2 or 3, characterized in   that the first and / or second elastic return means urge the external tool (13) against a wall (32) of the operating window (12).   5. Terminal block according to any one of claims 2 5 to 4, characterized in that the first and / or second return means extend over substantially the entire height of the window.   maneuver (12) and protrude inside thereof.   6. Terminal block according to any one of claims 2   to 5, characterized in that the first and / or second return means 10 comprise at least one convex tab (36) whose convexity is   turned towards the inside of the operating window (12).   7. Terminal block according to claim 6, characterized in that the convex tab (36) extends over the entire width of the window operation (12).   8. Terminal block according to any one of claims 2   to 5, characterized in that the first and / or second return means comprise at least two teeth (38) which project inwards from the operating window (12).   9. Terminal block according to any one of claims 2 20 to 5, characterized in that the first and / or second return means   comprise two convex tabs (45, 46) whose convexity is turned towards the inside of the operating window (12) and which protrude in the angles of it.