EP0780923B1 - Clamp for connecting a conductor end with a contact - Google Patents

Description

The invention relates to a terminal for connecting a conductor end to a, in particular fixed, contact, in particular to a busbar or a contact of a fuse carrier,
the U-shaped holder comprising the contact itself or having it itself and a clamping member seated in the holder and pressing the conductor end against the contact in the form of a one-armed lever mounted with its lever axis in the holder, the longer arm of which than a push handle underneath Pressing the, shorter, load arm to the end of the conductor and tightening a spring in a hooking with the bracket can be locked

Such a clamp is known from WO-A-91/20110 in the alternative that the bracket even has the contact. The bracket consists of one, especially the rear Molded end of a connector pin, molded part. The molded part has a front wall, a back wall and in between a flat contact surface. In the front wall there is a U-shaped opening through which the conductor end is inserted. The The bottom of the opening is higher than the contact surface, so that this is due to the clamping member Conductor end pressed against the contact surface is forced into a double kink becomes. The clamping element in the form of a one-armed lever bent from elastic sheet metal with a load arm bent back under the power arm to form a kind of sleeve pushed with the sleeve onto a rod formed on the molded part as a lever axis.

For a long time actually used and widely used are clamps with a screw Clamping member.

The invention has for its object a simple to manufacture in multiple Way to create executable and easy and quick to use clamp.

According to the invention it is provided for this purpose in a clamp of the type mentioned at the outset that the holder consists of a U-shaped, resilient sheet metal,
that the lever axis is formed by two stubs emerging in alignment with one another on both sides of the lever and
that the two stubs are inserted into recesses of the two, elastically expandable, cheeks of the holder and are stored therein,
the conductor end between the two U-cheeks is to be inserted parallel to these and for arranging the contact in the terminal
the two U-cheeks have an incision with which the holder can be pushed onto a busbar,
or have a distance from one another at which the holder can be placed on a contact tongue,
or the bracket is in contact with the U-bar itself.

In another variant, it is provided that the holder consists of a flat, U-shaped sheet,
that the lever axis is formed by one end of the lever,
which is inserted into a recess of the one cheek of the holder and stored therein or hooked onto a projection or two lateral projections of the U-cheek,
the end of the conductor must be inserted between the two U-cheeks transversely to them and the other U-cheek is forked or angled for this purpose,
and for arranging the contact in the terminal, the holder with the U-web seat for the conductor end and contact itself.

The invention replaces that in the known clamp forming the bracket, complex Shaped part with the molded rod by means of a sheet metal part, which is also otherwise designed two recesses in the first variant and one recess in the second variant and inserting the lever with its lever axis provided on it into the recess (s).

In the first variant, with the spring and conductor arrangement rotated through 90 °, there is also a possibility of making contact with a busbar or a contact tongue.
In comparison with the known screw terminals, there is the advantage of assembling the terminal by hand without using a tool. With an easily possible application of force of 100 N with the thumb, for example, a pressing force of 250 to 300 N or more is generated. However, the pressure handle can also be depressed using a tool, for example a screwdriver; he can make a small dent or the like. have to attach the tool. This enables assembly under tension. The one-armed lever is short. The clamp remains in a reasonable size.

Said spring can, for example, hold the pivot bearing of the lever resiliently or be arranged on the power arm in such a way that it presses on the conductor end.
Expediently, however, the lever itself is the spring in the manner known per se, in the form of a spiral spring, so that no separate part has to be attached for the suspension. The load arm is then preferably bent back, preferably somewhat behind, the lever axis under the power arm.
With this shape, the spiral spring is of sufficient length to provide a comparatively large amount of travel. However, their structural dimensions are relatively small.

The spiral spring at the end of the load arm is preferably bent out toward the end of the conductor, so that it presses on it with an edge. The edge made of spring steel will then press a little into the conductor end, which usually has a copper sleeve, and hold it accordingly in the longitudinal direction.
It can also be created only by a slight notch at the spring end, which can be formed when punching out the spring plate, a centering holding the conductor end in the transverse direction.

At the end of the power arm, the lever is expediently bent, as is known per se, in order to hook at the end of the bent section under a projection of the holder. The hook can be formed by a bend, preferably by 180 °.
The lever arm has the greatest possible length. The bend also creates a rounding, with which the lever end does not press sharply into the thumb when the spring is tensioned and engaged.

The bent portion can be a breakthrough for the engagement of a screwdriver have, such that the bent portion by means of a screwdriver for unhooking something can be bent back.

The two stubs emerging from the sides of the lever, which form the lever axis according to the invention, are preferably rectangular. They do not require their own work step; the two stubs can also be shaped when the lever is shaped.
The lever in the form of the spring is not weakened by the stubs attached, compared to other possible solutions.

The two stubs are expediently mounted in recesses of two elastically expandable cheeks of the holder.
As a particularly advantageous embodiment, it is proposed that the recesses each have approximately the shape of two diagonally cut-out quarter circle cutouts which overlap at the tips.
The stubs are then not only guided around the circumference of the recesses. They also have an axle-like bearing in the middle between two tips.

The plate of the holder can also in the case of the holder itself representing the contact are made of copper.

In a further advantageous embodiment of the invention it is proposed that the lever of the shape of the spiral spring along its length in roughly the same width the bending moment is changed. So you can with a constriction of the spiral spring equalize the bending of the length of the power arm and / or the load arm.

By influencing the bending stress in the proposed manner, the bending is relocated from places where there is a high bending moment due to the basic shape of the bending spring and the flow of forces, to places with a lower bending moment. As a result, the spiral spring can remain dimensioned as a whole without the bend anywhere coming too close to the area of permanent deformation.
The spiral spring should be guided laterally in the holder and thus at least in the vicinity of the stub and preferably also at the end of the load arm have the clear width of the holder; at the end of the power arm, it should offer the thumb a comfortable pressure surface. On the lengths in between, with the constrictions mentioned, the width of the spiral spring should decrease from the stubs towards the, again wider, ends, ie in the direction of the decrease in the bending moment.

For the holder according to the variant of the invention, it is more specifically proposed that the one U-cheek forms an end wall and a seat, which forms the contact and preferably has two lateral borders, for the end of the conductor extends at a right angle to the end wall and preferably on the right the end wall opposite the end of the holder at a right angle to the seat than the other U-cheek, a frame is formed on which the other end of the lever can be snapped and in which the conductor is to be inserted.
The associated lever preferably has a pressure element that branches off along the length of the power arm in order to form the load arm. If it is inserted into the mentioned recess, it can also be hooked on.

Advantageous configurations of the lever and the frame mentioned, in which it engages, are described in more detail in the following description of exemplary embodiments of the Invention and cited in the dependent claims.

Fig. 1

zeigt in isometrischer Darstellung eine Klemme auf einer Sammelschiene im Endzustand,

Fig. 2

zeigt in gleicher Darstellung wie Fig. 1 die Klemme in geöffnetem Zustand,

Fig. 3

zeigt ein Einzelteil in isometrischer Darstellung,

Fig. 4

zeigt die Klemme nach Fig. 1 und 2 in axialem Schnitt,

Fig. 5

zeigt in einem Fig. 4 entsprechenden Schnitt eine Variante,

Fig. 6

zeigt einen Fig. 4 entsprechenden Schnitt ohne Leiterende,

Fig. 7

zeigt einen Sicherungsträger mit eingesetzter Sicherung und mit einer angesetzten zweiten Klemme in isometrischer Darstellung,

Fig. 8

zeigt die Klemme nach Fig. 7 in axialem Schnitt,

Fig. 9

zeigt teils in Seitenansicht und teils in axialem Schnitt eine dritte Klemme im Endzustand,

Fig. 10

zeigt teils in Seitenansicht und teils in axialem Schnitt eine vierte Klemme im Endzustand und

Fig. 11

zeigt teils in Seitenansicht und teils in axialem Schnitt eine fünfte Klemme im Endzustand.

The drawings show exemplary embodiments of the invention.

Fig. 1

shows an isometric view of a terminal on a busbar in the final state,

Fig. 2

shows in the same representation as Fig. 1, the terminal in the open state,

Fig. 3

shows an individual part in isometric representation,

Fig. 4

shows the clamp of FIGS. 1 and 2 in axial section,

Fig. 5

4 shows a variant in a section corresponding to FIG.

Fig. 6

4 shows a section corresponding to FIG. 4 without the end of the conductor,

Fig. 7

shows a fuse carrier with inserted fuse and with an attached second terminal in an isometric view,

Fig. 8

7 shows the clamp according to FIG. 7 in axial section,

Fig. 9

shows partly in side view and partly in axial section a third clamp in the final state,

Fig. 10

shows partly in side view and partly in axial section, a fourth terminal in the final state and

Fig. 11

shows partly in side view and partly in axial section a fifth terminal in the final state.

The, designated 1, clamp according to FIGS. 1 to 6 consists of a holder 2 and a spiral spring 3.

The bracket 2 has the shape of a U-shaped angled sheet.
The U-cheeks 4 have two oblong-rectangular incisions 5 the width of a busbar. With the incisions 5, the terminal 1 is pushed onto the busbar designated 6.
Closer to their end edges 15, the U-cheeks 4 have two aligned recesses 8 in lateral extensions 7.

The recesses 8 have approximately the shape of opposite circular sections 9. Die Arc length of the circular sections is just over 90 °. The pages are however still perpendicular to each other. Pages 10 and 11 of the various pages are thus located Circular sections that would be aligned with each other if the sector shape were precise and the tips 12 of the sheet metal sections remaining between the circular sections 9 13 are spaced apart.

On the other side of the U-cheeks 4, projections 14 are formed, slightly inclined in a hook-like manner.
From the two U-cheeks flaps 16 bent inwards form an end abutment for the conductor end.
One of the two U-cheeks 4 also has an inward bend 17, from which a tongue 18 is angled axially, which then changes into a slight inclined position.
5, this U-cheek 4 also has, at the end of the incision 5, an inwardly angled web 19 which, in a central region between the two U-cheeks 4, has a projection 20 which extends beyond the alignment of the incisions 5 ,

The spiral spring 3 is mounted with two side stubs 21 in the recesses 8 of the two U-cheeks 4. It thus forms a lever with a force arm 22 and a load arm 23. The load arm 23 is formed by bending the spring plate back and forth in connection with the force arm 22, ie behind the lever axis located at one tip 12. The effective spring length is thus increased beyond the lengths of the force arm and the load arm by the portion 45 lying beyond the tip 12.
The load arm 23 is bent outwards at 31 and provided with a slight notch 24 at its end edge. The power arm 22 is angled at the end and the end of the angled section 25 is bent back, forming a hook 26. The angled section 25 has an opening 27.

On the angled section 25 and a section adjoining this 28 of the power arm 22, the spiral spring 3 covers the U-cheeks 4. A constriction follows 29. The spiral spring then widens again, in front of and behind the Stub 21 to occupy the clear width between the U-cheeks 4. Go on the spiral spring on the load arm 23 into a second constriction 30. On the bent out At the end of 31 it again assumes the clear width between the U-cheeks 4.

If the terminal 1, in the open position according to FIG. 2, is pushed onto the busbar 6, it presses the tongue 18 down and then engages behind it. By pressing the spiral spring 3 into the position according to FIG. 6, the hook 26 hooks behind the projections 14 and the end edge of the load arm 23 is pressed lightly onto the busbar 6. Both parts 2 and 3 of terminal 1 are thus free of play on the busbar 6. To bring the terminal 1 back into the open position, grasp the opening 27 with the tip of a screwdriver and bend the angled section 25 slightly outwards.
In this position, see FIG. 2, a conductor end 32 can be inserted. It is inserted between the U-cheeks 4 over the busbar 6 until it abuts the tabs 16. The force arm 22 is pressed down by the pressure of the thumb on the wide end section 28, the index finger being able to hold under the holder 2, ie on the underside of the U-back, until the hook 26 engages again under the projections 14. The end edge of the load arm 23 now lies with the notch 24 on the conductor end 32 and presses it against the busbar 6, where the electrical connection then exists. The power arm 22 and the load arm 23 are now a little bent, the back bend beyond the lever axis is a little more bent than before.
The load arm 23 rests on the conductor end 32 with inclined inclination in the compressive sense and holds it accordingly. The bend at the end of the angled section 25, on the other hand, represents a rounding that can slide relatively easily over an inclined surface 33 arranged on the U-cheeks 4 and can press the section 25 outwards until the hook 26 snaps into place.

The above-mentioned offset of pages 10 and 11 of circular sections 9 has about the extent of the sheet thickness of the spiral spring 3. Their stub 21 are in the Open position on the sides 10 (Fig. 2) and are in the clamping end position near the sides 11, but on one tip 12 (Fig. 1, 4 and 5).

In the variant according to FIG. 5, the protrusion 20 of the web 19 holds over the busbar 6 the conductor end 32 here at a distance from the surface of the busbar 6. As a result, the conductor end 32 on the other side at the edge there Busbar 6 a kind of point contact 44 with a correspondingly larger surface pressure.

7 shows a fuse carrier 34 with a base part 35 and two holding elements 36 and at the same time contacts for a fuse 37. The front holding element 36 merges into a contact tongue 38. This is enclosed by a bracket 39 adapted to it, a clamp 40, which in turn has the spiral spring 3 as a clamping member. The bracket 39 differs from the bracket 2 in the main that it does not receive the contact tongue 38 like the bracket 2, the busbar 3, in one cut, but in the enclosure formed by the U-back and the U-cheeks 4 ,
The bracket 39 is fastened together with the front holding element 36 to the base part 35 with a screw 41.
An embossed bulge 42 in the contact tongue 38 creates a secure electrical connection with the conductor end to be placed on the contact tongue 38.

The terminal shown in FIG. 9, designated 51, has a holder 52 which, from a flag 53 serving for its electrical further connection, leads into an end wall 54 which is angled therefrom and is stepped by two further angulations, and from this into an angled seat 55 which is followed by a section 57 set back by a crank 56 and finally merges with a further bend into a fork 58 opposite the end wall 54 at the other end of the holder 52; the fork ends 59 form a last bend further in the longitudinal direction.
The structure described is made from a stamped part made of copper sheet. It is relatively narrow on the seat 55 in order to accommodate a stripped conductor end 61 between two upturned enclosures 60. In contrast, the fork 58 is widened. The conductor provided here with the insulation 62 is brought through its intermediate space. The insulation 62 is located in the cranked section 57. The conductor end 61 is inserted until it abuts the section 63 of the end wall 54 located below the step.
The section of the end wall 54 located above the step is provided with a rectangular opening 64.

A one-armed lever consisting of a spiral spring 66 is inserted into the opening 64 with a hook-shaped bent-out and angled end. With a glued, screwed or riveted, angular pressure element 67, he presses the conductor end 61 onto the seat 55, which represents the contact. At the other end, the spiral spring 66 is angled and finally provided with an inclined surface 69 at its angled section 68.
Here, while the index finger is holding against the section 57 of the holder 52, it is pressed down with the thumb under bending. The sloping surface 69 meets the end edges of the fork ends 59 and thus bends the angled section 68 until it snaps under the angled fork ends 59 with lateral projections projecting perpendicularly to the drawing plane.

Fig. 10 shows a clamp with the same holder 52 and a functionally the same Bending spring 66, which only has another pressure element 70. The pressure element 70 is formed by a lateral branch from the spiral spring, by two Folding at 71 and at right angles to it at 72 under the spiral spring 66 is brought so that the end portion 73 with its edge transversely on the conductor end 61st lies.

4, an angular frame 74 is formed on the bracket 52 instead of the fork 58. One angle leg 75 is at right angles to the seat 55, to the side of the longitudinal axis of the holder 52. The other angle leg extends parallel to the transverse axis of the holder 52. The conductor is accommodated under this other angle leg 76. On the angle leg 76, a projection 77 is bent back in the middle.
The spiral spring designated here with 78 is not provided with a pressure element that branches off along its length to form the load arm, but is bent back under the power arm at its pivoting end. It snaps into the projection 77 of the frame 74 with a cutout 79 arranged in it on the back bend.

The bent-back section 80 presses with its end edge onto the conductor end 61 and is supported in the end position in FIG. 11 with a bulge 81 on the force arm of the spiral spring 78.
The design of the spiral spring 78 with the bent-back section 80 is particularly adaptable to conductor ends of different thicknesses; the bent-back section 80 can also project freely instead of resting against the power arm.

It is more appropriate to make it narrower than the rest of the section Bending spring to adjust the contact pressure and the bending behavior of the bending spring 78 certain requirements.

The spiral spring could also be similar or similar to that shown in FIG. 11 on its pivoting End is bent back and snapped into place at its other end instead bent back and stored to form the pivot axis.

Claims (18)

1. Terminal for connecting a conductor end (32) to a contact (6; 38), in particular a fixed contact, in particular to a bus bar (6) or a contact (38) of a fuse carrier,
   which has a U-shaped holder (2; 39), enclosing the contact (6; 38) or having the contact itself, and a clamping member (3), which is seated in the holder (2; 39), presses the conductor end (32) against the contact (6; 38) and is in the form of a one-armed lever (3), which is mounted with its lever spindle (12) in the holder (2; 39) and the longer, power arm (22) of which can, as a pressure grip (28), be made to engage with the holder (2; 39) in a hook arrangement (14, 26) by pressing the shorter, load arm (23) onto the conductor end (32) and tensioning a spring (3),
   characterized in that the holder (2) comprises a resilient metal sheet bent in a U-shaped manner,
   in that the lever spindle is formed by two stubs (21) protruding in line with each other on the two sides of the lever (3) and
   in that the two stubs (21) are inserted into recesses (8) in the two, flexibly spreadable side faces (4) of the holder (2) and are mounted therein,
   the conductor end (32) being able to be introduced between the two U side faces, parallel to the latter, and, for the arrangement of the contact in the terminal,
   the two U side faces (4) having an incision (5) which allows the holder (2) to be pushed onto a bus bar (6),
   or are at a distance from each other which allows the holder (39) to be placed onto a contact tongue (38),
   or the holder with the U cross-piece is itself the contact.
2. Terminal for connecting a conductor end (61) to a contact (55),
   which has a U-shaped holder (52), having the contact (55), and a clamping member (66; 78), which is seated in the holder (52), presses the conductor end (61) against the contact (55) and is in the form of a one-armed lever (66; 78), which is mounted with its lever spindle (65) in the holder (52) and the longer, power arm of which can, as a pressure grip, be made to engage with the holder (52) in a hook arrangement (59; 77, 79) by pressing the shorter, load arm onto the conductor end (61) and tensioning a spring (66; 78),
   the holder (52) comprising a metal sheet bent in a flat U-shaped manner,
   the lever spindle being formed by one end of the lever (66; 78),
   which is inserted into a recess (64) in one side face (54) of the holder (52) and is mounted therein or is hooked on a projection or two lateral projections of the U side face,
   the conductor end being able to be introduced between the two U side faces transversely in relation to the latter and, for this purpose, the other U side face (58; 74) being forked (58) or angled (74),
   and, for arrangement of the contact in the terminal, the holder (52) with the U cross-piece providing a seating (55) for the conductor end (61) and even the contact (55).
3. Terminal according to Claim 1 or 2, characterized in that the lever (3; 66; 78) itself is the spring (3; 66; 78) in the form of a bending spring (3; 66; 78), preferably of stainless steel.
4. Terminal according to Claim 3, characterized in that the load arm (23) is bent back at, preferably somewhat behind, the lever spindle (12) under the power arm (22).
5. Terminal according to Claim 3, characterized in that, for forming the load arm, the bending spring (78) is bent back at the pivoting end of the power arm under the latter (80).
6. Terminal according to Claim 4 or 5, characterized in that the bent-back portion (80) of the bending spring (78) is supported on the power arm in the end position.
7. Terminal according to Claim 3, characterized in that, for forming the load arm, the lever (66) has a pressure element (67; 70) branching away on the length of the power arm.
8. Terminal according to Claim 7, characterized in that the pressure element (67) is adhesively attached, screwed or riveted onto the load arm or in that it (70) is formed by a lateral branch, which is brought under the load arm by bending around twice (71; 72), preferably about axes at right angles to each other.
9. Terminal according to one of Claims 4 to 8, characterized in that the bending spring (3) is bent out (31) at one end of the load arm (23) towards the conductor end (32) and is preferably slightly notched (24) as a centring for the conductor end.
10. Terminal according to one of Claims 1 to 9, characterized in that the lever (3) is bent around at the end of the power arm (32) and hooks in at the end of the bent-around portion (25) under a projection (14) of the holder (2), preferably with an angled-around formation (26), preferably by 180°.
11. Terminal according to Claim 10, characterized in that the bent-around portion (25) has an aperture (27) for the engagement of a screwdriver.
12. Terminal according to one of Claims 1 to 11, characterized in that the lever of the form of the bending spring (3; 66, 78) is changed in its width over its length approximately synchronously with the bending moment.
13. Terminal according to Claim 12, characterized in that the bending spring (3) has on the length of the power arm (22) and/or of the load arm (23) a constriction (29 and 30, respectively), which increases towards the end of the load arm (23) or power arm (22).
14. Terminal according to Claim 1 or one of Claims 3 to 13, characterized in that the recesses (8) respectively have approximately the form of two quarter-circle cutouts (9) put together diagonally in such a way that they overlap at the tips.
15. Terminal according to one of Claims 2 to 13, characterized in that
    in the holder of sheet metal bent in a flat U-shaped manner, one U side face forms an end wall (54), and a seating (55) for the conductor end (61), which forms the contact and preferably has two lateral receptacles (60), extends at an angle, preferably at right angles, in relation to the end wall (54), and, at the end of the holder (52) lying opposite the end wall (54), there is formed at an angle, preferably at right angles, in relation to the seating (55) as the other U side face a frame (58; 74), on which the other end of the lever (66; 78) can engage and into which the conductor is to be placed.
16. Terminal according to Claim 15, characterized in that the frame (58) is fork-shaped and the conductor is accommodated in the fork (58), and the lever (66) snaps with projections, in particular lateral projections, under the bent-around fork ends (59).
17. Terminal according to Claim 15, characterized in that the frame (74) is angular, one angle leg (75) being disposed at the said angle, preferably right angles, in relation to the seating (55), to be precise to the side of the longitudinal axis of the holder (52), and the other angle leg (76) extending parallel to the transverse axis of the holder (52), and the conductor being accommodated under this other angle leg (76), and the lever (78) being able to engage on this other angle leg (76).
18. Terminal according to Claim 17, characterized in that, on the said other angle leg (76), a projection (77) is bent back and the lever (78) engages under the latter (77, 79).

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