EP2019449B1 - Screw-clamp and method for manufacturing thereof - Google Patents

Description

The invention relates to a screw terminal according to the preamble of claim 1, an installation switching device with a screw terminal according to claim 6, and a method for producing a screw terminal according to claim 8.

A generic screw terminal comprises a substantially frame-like clamping member with longitudinal, narrow and broad sides, a clamping screw which is received in a threaded opening of the clamping member, and a the interior of the frame-like clamping member by cross, movably arranged to the clamping part busbar whose broad side in mounted Condition is oriented parallel to the broad side of the clamping member, wherein the clamping member is displaceable by turning the clamping screw in its longitudinal direction relative to the busbar, so that a connection conductor between the clamping screw facing away from the side of the busbar and the clamping screw facing away from the broad side of the clamping part is clamped, wherein the busbar carries at its free end in an approximately rectangular contact plate whose length is greater than the width of the busbar receiving interior of the clamping part, so that the contact plate in the assembled state of the busbar with their free ends on both sides of the frame-like clamping part surmounted.

Such Schraubabschlussklemmen are also known as Zugbügelklemmen. The DE 40 13 225 B4 , the DE 101 55 924 A1 , and the EP 0 847 105 A1 show examples of embodiments of generic Zugbügelklemmen. These are usually used in service switching devices, for example in circuit breakers or RCCBs, to connect connecting conductors, be it stripped cable ends of flexible wiring cables or fixed contact lugs of busbar arrangements, to the service switching device. Installation switching devices are known to monitor the current flow on one of an input side leading to an output terminal through the inside of the device current path and turn on or off. For this purpose, the screw terminals are mounted inside the service switching device housing in a terminal receiving space, which is usually housed near the narrow side of such a service switching device.

The EP 0 541 459 A1 shows a Zugbügelklemme in an installation device housing, wherein the clamping frame has teeth that cause when tightening the Clamp the two housing halves of the device housing are pulled towards each other.

The EP 1 596 471 A1 shows a terminal assembly in which the clamping frame is formed together with the clamped terminal conductor as a replaceable and snap-in a corresponding terminal receiving space of a device module.

The US Pat. No. 2,159,757 shows a clamping arrangement in which a terminal conductor can be clamped by means of a cage clamp to a busbar, and the busbar with clamped conductor can then be inserted into a device.

The EP 0 893 846 A1 shows a Zugbügelklemme, in which an additional clamping zone is provided for clamping another conductor.

The FR 2 459 560 shows a Zugbügelklemme for clamping an insulated connection conductor, wherein means are provided to pierce the insulation when tightening the clamping screw and make an electrical connection to the conductive core of the connection conductor.

The busbar is mounted stationary in installation devices with Zugbügelklemmen inside the housing usually. At their the device interior facing free end internal connection conductors are attached, which continue the current path between the input and output terminal, wherein the current path is still performed on other functional components or components inside the housing, for example via a contact point and possibly a thermal or magnetic trigger.

Since the busbar is mounted stationary, shifts the clamping member relative to the busbar upon actuation of the clamping screw. It is often necessary in the manufacture of a service switching device to perform a so-called hot adjustment of the thermal release at the end of the manufacturing process. For this purpose, the busbars of the input and output side terminals are contacted in a tester by probes under a certain contact pressure, it may happen that the busbar is pressed by the contact pressure of the probe from its specified position into the interior of the housing, so that the device no longer usable.

It is therefore an object of the present invention to provide a generic screw terminal and a service switching device with such a screw, which is designed so that by external contact pressure displacement of the terminal is avoided inside the device housing, and which is designed so that in high speed can be produced on a production and assembly machine.

The object is achieved with respect to the screw terminal by a generic screw terminal with the characterizing features of claim 1.

Thus, according to the invention, the length of the contact plate is smaller than the height of the busbar receiving the interior of the clamping plate.

The advantage of the inventive design of a screw is that the clamping part laterally projecting free ends of the busbar can be used as an abutment with which the busbar near the Leiteinfirhrungsungsöffnung the Schraubanschlussklemme can be supported in addition to abutments in the interior of the housing and thereby pushing the Schraubverbindkletnme is prevented by a pressing on the outside of them probe. The invention Dimensionlerung the ratio between the length of the contact plate and the length of the busbar receiving the interior of the clamping part allows a simple and fast automatic assembly of the screw terminal according to the invention.

According to a particularly advantageous embodiment of the invention, the clamping screw receiving threaded opening is mounted in a broad side of the frame-like clamping part. The clamping member may be a stamped and bent part with a particularly reinforced upper broad side, in which the thread is introduced. The busbar receiving the interior of the clamping member then extends in the longitudinal direction of the frame-like clamping plate between the upper and lower broad side. The lower broad side can also be rounded or arcuate.

According to a further advantageous embodiment of the invention, the broad side of the contact plate is aligned approximately perpendicular to the broad side of the busbar. Since the broad side of the busbar approximately parallel to the broad side of the clamping part and perpendicular to the receiving opening for the connecting conductor-carrying longitudinal side of Clamping part is oriented, so that the contact plate extends with its broad side parallel to this receiving opening for the connecting conductor-carrying longitudinal side of the clamping part. The contacting by means of the probe during the hot adjustment can then take place from the same direction, from which in the intended use of the service switching device, a connection conductor would be introduced into the screw terminal.

The contact plate is advantageously integrally connected to the busbar. In a further particularly advantageous manner, the busbar is formed as a stamped and bent part, and the contact plate is formed after punching the busbar by bending an end piece of the busbar.

With regard to the service switching device, the object is achieved by an installation switching device with an insulating housing, which has at least one front side and a mounting side and the front and the attachment side connecting narrow and broad sides, and which in the narrow sides of a terminal receiving space for a terminal for connecting an electrical Connecting conductor has, with a screw terminal according to the invention, in which near the narrow side of the housing in the housing interior holding means for a stationary mounting of the free ends of the contact plate are provided.

In a particularly advantageous embodiment, the holding means may be designed as plug-in pockets which are mounted near the narrow side of the housing on the inner housing broadside and whose internal dimensions correspond to the outer dimensions of the free ends of the contact plate. In particular, in service switching devices with a Isolierstoffgehäuse in shell construction, in which so two housing half shells along a joint line juxtaposed and interconnected, it is advantageous if a first pocket in the first housing half shell and the second pocket are mounted in the second housing half shell. The screw terminal is then initially inserted with a first side part in the first slot in the assembly, then the second housing half shell is placed on the first housing half shell, in which case the second side part at the same time in the second pocket is introduced. If the two housing halves are then connected to each other, the screw terminal is held almost immovable with the free ends of the bus bar in the pockets.

• Ausstanzen der Stromschienen aus dem Stanzbereich eines längserstreckten Blechstreifens unter Beibehaltung einer Verbindung der Stromschienenschmalseiten mit dem Transportbereich des Blechstreifens,
• Umbiegen des freien Endes der ausgestanzten Stromschienen zur Bildung der Kontaktplatten,
• Aufschieben des um 90° gegenüber der Montageposition in der Schmalseitenebene gedrehten, vorgefertigten Klemmteiles über das freie Ende der Stromschienen, so dass die Kontaktplatte das Klemmteil überragt,
• Zurückdrehen des Klemmteiles um 90°, so dass dieses bezogen auf die Stromschiene in seine Montageposition zu liegen kommt und die Kontaktplatte mit ihren Das Klemmteil überstehenden freien Enden ein Abgleiten des Klemmteiles von der Stromschiene verhindert, sowie
• Trennen der Stromschiene mit dem aufgesetzten Klemmteil von dem Transportbereich des Blechstreifens und damit Vereinzeln der fertig montierten Schraubanschlussklemmen.

An inventive method for producing a screw terminal according to the invention is characterized by the following method steps:

• Punching the busbars from the punching area of a longitudinally extending metal strip while maintaining a connection of the busbar narrow sides with the transport area of the sheet metal strip,
• Bending the free end of the punched busbars to form the contact plates,
• Sliding the pre-fabricated clamping part rotated by 90 ° with respect to the mounting position in the narrow side plane over the free end of the busbars, so that the contact plate projects beyond the clamping part,
• Turn back the clamping part by 90 °, so that this comes to lie in relation to the busbar in its mounting position and the contact plate with its clamping part protruding free ends prevents slipping of the clamping part of the busbar, as well
• Separating the busbar with the attached clamping part of the transport area of the sheet metal strip and thus separating the fully assembled screw terminals.

The advantage of the manufacturing method according to the invention is that the steps "punching the busbar", "bending the busbars" and "placing the clamping parts on the busbar" are consecutively performed on interconnected via the transport strip parts, wherein the transport strip automatically when punching the busbars arises and does not have to be added separately and the bus bars are automatically aligned and positioned for the placement of the clamping part, so that the method can be carried out automated at high speed. A suitably designed production machine gets as a supply of material only an endless metal strip and the prefabricated, frame-like clamping parts. From the sheet metal strip the busbars are punched out, with a lateral strip stops as a transport strip, by means of which the punched busbars are transported to the other workstations. At a next station within the machine then the free end of the busbar is bent so that thereby the contact plate is formed in the predetermined position on the busbar. On the transport strip, the busbars with the contact plates are continued to that station at which the clamping parts are pushed onto the busbars.

For this purpose, the inventively tuned ratio of the length of the interior of the frame-like clamping part, the length of the contact plate and the width of the insertion opening for the connecting conductor receiving longitudinal side of the clamping part is now important. Because this makes it possible that the clamping part - rotated by 90 °, so that the longitudinal extension direction of the longitudinal side of the frame-like clamping member is parallel to the longitudinal direction of the contact plate - can be pushed over the contact plate and on the busbar. Now, this is brought by a 90 ° rotation of the frame-like clamping member in a position such that the contact plate is perpendicular to the longitudinal direction of the longitudinal side of the clamping member and in this position, the side parts of the busbar laterally project beyond the frame-like clamping member, whereby the clamping member on the free end of the busbar can no longer slide off the busbar. The other end of the busbar is still attached to the transport strip, so that the clamping member is already completely connected in this manufacturing step captive with the busbar. The handling up to here is much easier because of the fixation on the transport strip, which is also material supply for the punching of the busbar, as if in the previously known conventional manner from the outset individual busbars would be supplied. Because these would then have to be sorted in the machine, aligned and kept for placing the clamping part, which complicates the handling.

Advantageously, the clamping screw has already been inserted into the clamping part, before it is pushed onto the busbar. Then, before singulating the screw terminals of the sheet metal strip, the clamping screw are tightened so far that the clamping part is fixed to the busbar.

If, as a last step, the screw connection clamp is separated from the transport strip and thus separated, they are completely assembled. Optionally, only a post-processing of the separating edge is necessary, such as a deburring.

Further advantageous embodiments and improvements of the invention and further advantages can be taken from the subclaims.

Reference to the drawings, in which an embodiment of the invention is shown, the invention and further advantageous refinements and improvements of the invention will be explained and described in detail.

Figur 1

eine erfindungsgemäße Schraubenanschlussklemme,

Figur 2

eine zweite Ausführungsform einer erfindungsgemäßen Schraubenanschlussklemme,

Figur 3

eine Einsicht in eine geöffnete Gehäusehalbschale eines erfindungsgemäßen Installationsschaltgerätes mit einer erfindungsgemäßen Schraubanschlussklemme,

Figur 4

eine zweite Einsicht in eine geöffnete Gehäusehalbschale eines erfindungsgemäßen Installationsschaltgerätes mit einer erfindungsgemäßen Schraubanschlussklemme, sowie

Figur 5

eine schematische Ansicht eines Transportstreifens bei der Anwendung des erfindungsgemäßen Herstellungsverfahrens für die erfindungsgemäßen Schraubanschlussklemmen.

Show it:

FIG. 1

a screw terminal according to the invention,

FIG. 2

A second embodiment of a screw terminal according to the invention,

FIG. 3

an insight into an open housing half shell of a service switching device according to the invention with a screw terminal according to the invention,

FIG. 4

a second insight into an open housing half shell of a service switching device according to the invention with a screw terminal according to the invention, and

FIG. 5

a schematic view of a transport strip in the application of the manufacturing method according to the invention for the screw terminals according to the invention.

The FIG. 1 Thus, FIG. 1 shows a screw connection terminal 1, as can be installed in service switching devices, which has a clamping screw 2, a substantially frame-shaped clamping part 3 and a busbar 4.

The clamping part 3 is formed by a slotted conductor strip 5, which is bent into an approximately rectangular or box-shaped frame. The two free ends 6, 7 of the slotted conductor strip 5 are bent at right angles to each other, so that they form overlapping frame legs, which constitute the upper broad side 8 of the clamping part 3. In the upper broad side 8 is an opening 9 with internal thread for receiving the clamping screw. 2

The upper broad side 8 opposite lower broad side 10 of the clamping part 3 is executed here rounded. However, it could also be flat, but this would mean an additional processing step in the production of the clamping part 3.

The clamping part 3 has an open frame shape, whereby on the longitudinal side 11 an insertion opening 12 is formed for the connecting conductor to be connected.

The narrow side 13 of the clamping part 3 is formed due to the slit of the clamping part 3 forming the conductor strip 5 substantially by two mutually parallel longitudinally extending webs 14, 15 with an intermediate recess 16, wherein the webs 14, 15 are held together with crossbars 17.

The busbar 3 has substantially the shape of a rectangular, flat conductor piece. It is guided displaceably in the interior of the clamping part 3 between the upper and the lower broad side 8, 10 in the longitudinal extension direction of the clamping part 3. At its the insertion opening 12 facing away from the free end 18, the busbar for connecting a further, leading into the interior of the service switching device connection conductor is established. For this purpose, it carries there a rectangular recess and a bore 19. Furthermore, the busbar is provided there at a bending edge 20 with a stepped turn, so that the free end 18 is displaced parallel to the rest of the busbar by a distance x down.

The insertion opening 12 facing free end 21 of the busbar 3 is bent at a bending edge 24 by about 90 ° upwards, so that it forms a contact plate 22. The contact plate 22 has a rectangular shape and extends with its broad side 23 parallel to the longitudinal side 11 of the clamping part 3, wherein it extends in the insertion direction of a connecting conductor in front of the longitudinal side 11 of the clamping part 3. there Project beyond the free ends 26, 27 of the contact plate 22 laterally the clamping part 3, so that the free ends 26, 27 with their the clamping part 3 projecting ends, so to speak holding tongues with which the contact plate in the housing of the service switching device are held in a correspondingly corresponding holder can, see FIG. 3 and 4 ,

On the longitudinal side of the busbar 3 guide tongues 25 are further formed, by means of which the busbar 3 in the recess 16 between the two parallel webs 14, 15 are guided on the narrow side 13 of the clamping part 3. The busbar can thus move between the transverse bracket 17 and the lower broad side 10 in the interior of the frame-shaped clamping part parallel to its longitudinal extension direction.

When the clamping screw 2 is tightened and screwed into the interior of the clamping part 3, it presses with its free end on the clamping screw 2 facing broad side of the busbar 4. Thereby, the clamping part 3 is displaced relative to the busbar 4 upwards, so that the lower broad side 10 moves toward the busbar 4 and between the busbar 4 and the lower broad side 10, a connection conductor is clamped.

The FIG. 2 shows a second embodiment of a screw terminal 30 according to the invention. It differs from that according to the invention FIG. 1 by the shape of the bus bar 4 in the part projecting into the interior of the housing. Same or similar parts are in the FIG. 2 denoted by the same reference numerals as in the FIG. 1 ,

The busbar is bent on its side facing the inside of the device initially by about 90 ° upwards to a vertical leg 41, at the end then turn by 90 °, a turn is made in a wagrechtes tail. About the vertical leg 41, an adjustment of the position of lying inside the housing assemblies to the position of the screw terminal 30 takes place.

An important feature in connection with the invention is that the length I of the contact plate 22 is smaller than the height H of the busbar 4 receiving interior of the clamping member 3 on the longitudinal side 11 between the upper and the lower broad side 8, 10. This feature allows a very fast, automated production of the screw terminal according to the invention, as now with reference to the FIG. 5 should be explained.

The FIG. 5 schematically illustrates the manufacturing steps of a manufacturing method according to the invention for a screw terminal in substeps a) to f). These method steps can be carried out, for example, in a high-speed production machine, which is not shown here.

A metal strip 31 carries at its right edge transport slots 32, by means of which it is moved forward with a transport device, for example by a gear, driven in the direction of transport of the arrow P.

In step b), the unwinding of the busbar 4 is punched out of the sheet metal strip 31 by means of a punching tool 34, while maintaining a connection later pointing into the housing interior narrow side of the busbar 4 with a standing on the right edge of the sheet metal strip 31 transport area or transport strip 33. The same reference numerals in the FIGS. 1 and 2 denote the same parts or the same sections as in the screw terminals 1 and 30 described therein.

In step c), the contact plate 22 is bent by 90 ° upwards, ie out of the plane of the drawing, which can be done by means of a bending tool integrated in the production machine. Due to the continuing coupling to the transport strip 33, the guidance and alignment of the development of the busbar 4 to the bending tool out is very easy and precise realized. Also further bends, for example, the vertical leg and the horizontal tail in a busbar according to FIG. 2 can be performed while the bus bar is still connected to the transport strip 33.

At a feeding station c), the clamping part 3 is now pushed over the free end of the busbar 4. The positioning of the feed is here again due to the leadership of the busbar 4 in a defined position, due to the connection with the transport strip 33, facilitated and simplified.

Thus, the contact plate 22 with its free ends 26, 27 does not hang, the clamping member 3 is first rotated by 90 °, so that it is greater than the length I of the insertion opening 12 on the open longitudinal side 11 whose height H yes Contact plate 22, can be pushed over the contact plate 22. After the clamping part 3 was thus then pushed onto the busbar 4, it is rotated back by 90 °, so that it then in the at the position c) in the FIG. 5 shown position on the still connected to the transport strip 33 power rail 4 is seated. The guide tongues 25 engage in the recess 16 between the two webs 14, 15 of the clamping part 3 and give the clamping part 3 stop on the busbar. 4

In the last step e) now the separation of the fully assembled screw terminals takes place by separating the connection with the transport strip 33rd

It will be the FIGS. 4 and 5 considered, which show an insight into an open half-shell 50 of a service switching device from different angles. The service switching device 50 has a front front side 51, rear front sides 52, a fastening side 53, the front and the fastening side connecting front and rear narrow sides 54, 55, and a broadside 61, and carries on the mounting side a fixed nose 56, with their Help the service switching device can be snapped onto a profile carrier rail. Other provided in the inside of the housing half-shell 50 structural elements that serve for holding or fixing other components, such as a switching mechanism or arc quenching plates, are of no importance to the essence of the present invention.

Near the rear narrow sides 55 a terminal receiving space 57 is provided each, into which a screw terminal according to FIGS. 1 or 2 is used. On the rear front side 52 is in a corresponding position with the clamping screw a screw opening 59, and on the rear narrow side 55 is in corresponding to the insertion of the screw terminal position an insertion 60 for a connection conductor.

Near the rear narrow side 55 pockets 62 are attached to the broad side 61 in the interior of the housing. In this guide tabs 25 formed by the free ends of the contact plate of the busbar 4 can be inserted. The depth of the pockets is at least as large as to choose the length z of the guide tongues 25, which is given by the length of the clamping part 3 superior portion of the free end 26, 27 of the contact plate 22, see FIG. 5 at step c).

The pockets 62 can be made during injection molding of the insulating half-shell 50 with.

By holding the busbar 4 of the screw in the plug-in pockets 62 prevents the screw terminal slips inside the device when pressure is exerted on the outside of the contact plate. This can be done, for example, when the service switching device is contacted after the final assembly in the hot adjustment by means of a probe on the contact plate 22.

The mounting of the screw terminal shown by means of pockets in the embodiments is not exhaustive, but also other equivalent acting support measures are conceivable, which should then be included in the present invention.

LIST OF REFERENCE NUMBERS

1

Screw Terminal

2

clamping screw

3

clamping part

4

conductor rail

5

slotted conductor strip

6

free end of the slotted conductor strip

7

free end of the slotted conductor strip

8th

upper broad side of the clamping part

9

opening

10

lower broad side of the clamping part

11

Longitudinal side of the clamping part

12

insertion

13

narrow side

14

web

15

web

16

recess

17

Querspange

18

free end

19

drilling

20

bending edge

21

free end

22

contact plate

23

Broad side of the contact plate

24

bending edge

25

guide tongue

26

free end of the contact plate

27

free end of the contact plate

41

vertical leg

42

horizontal tail

30

Screw Terminal

31

metal strip

32

transport slot

33

transport strip

34

punching tool

50

Housing shell

51

front front

52

rear front

53

mounting side

54

front narrow side

55

rear narrow side

56

firm nose

57

Terminal accommodation area

58

Screw Terminal

59

screw opening

60

insertion

61

broadside

62

put ashes

Claims (10)

1. Screw connecting terminal (1, 30) which comprises a clamping part (3), which is essentially in the form of a frame and has longitudinal, narrow and broad faces (11; 13; 8, 10), a clamping screw (2) which is held in a threaded opening (9) in the clamping part (3), and a busbar (4) which passes through the interior of the frame-like clamping part (3) and is arranged such that it can move with respect to the clamping part (3), and whose broad face when in the installed state is oriented parallel to the broad face (8, 10) of the clamping part (3), with the clamping part (3) being movable in its longitudinal direction relative to the busbar (4) by rotation of the clamping screw (2), such that a connecting conductor can be clamped firmly between the side of the busbar (4) which faces away from the clamping screw (2) and the broad face (10) of the clamping part (3) which faces away from the clamping screw (2), with the busbar (4) being fitted at its free end with an approximately rectangular contact plate (22) whose length (1) is greater than the width (B) of the interior of the clamping part (3) which holds the busbar (4), such that the free ends (26, 27) of the contact plate (22) project beyond the frame-like clamping part (3) on both sides when the busbar (4) is in the installed state, characterized in that the length (1) of the contact plate (22) is less than the height (H) of the interior of the clamping part (3) which holds the busbar (4).
2. Screw connecting terminal according to Claim 1, with the threaded opening (9) which holds the clamping screw (2) being fitted in a broad face (8) of the frame-like clamping part (3).
3. Screw connecting terminal according to Claim 1 or 2, with the broad face (23) of the contact plate (22) being aligned approximately at right angles to the broad face of the busbar (4).
4. Screw connecting terminal according to Claim 3, with the contact plate (22) being integrally connected to the busbar (4).
5. Screw connecting terminal according to one of the preceding claims, with the busbar (4) being in the form of a stamped and bent part, and with the contact plate (22) being formed by bending an end piece of the busbar (4) after the busbar (4) has been stamped out.
6. Service switching device, in particular a circuit breaker or residual current device, having an insulating material housing (50) which has at least one front face (51, 52) and one attachment face (53) as well as narrow and broad faces (54, 55, 61) which connect the front and attachment faces, and which service switching device has, in the area of the narrow faces (55), a terminal accommodation area (57) for a connecting terminal (1, 30) for the connection of an electrical connecting conductor, having a screw connecting terminal (1, 30) according to one of the preceding claims, characterized in that holding means (62) for mounting the free ends (26, 27) of the contact plate (22) in a fixed position are provided close to the narrow face (55) of the housing (50) in the interior of the housing.
7. Service switching device according to Claim 6, with the holding means being in the form of plug pockets (62) which are fitted to the inner housing broad face (61) close to the narrow face (55) of the housing and whose internal dimensions correspond to the external dimensions of the free ends (25, 26, 27) of the contact plate (22).
8. Method for production of a screw connecting terminal (1, 30) according to one of Claims 1 to 5, characterized by the following steps:

   - stamping out the busbars (4) from the stamping area of an elongated sheet-metal strip (31), while retaining a connection between the busbar narrow faces and the transport area (33) of the sheet-metal strip,

   - bending the free end of the stamped-out busbars in order to form the contact plates (22),

   - pushing the prefabricated clamping part (3), which is rotated through 90° with respect to the installed position in the narrow-face plane, over the free end of the busbars, such that the contact plate projects beyond the clamping part,

   - rotation of the clamping part (3) back through 90° such that it comes to rest in its installed position with respect to the busbar, and the free ends (26, 27, 25) of the contact plate, which project beyond the clamping part (3), prevent the clamping part (3) from sliding off the busbar (4), and

   - separation of the busbar (4) with the clamping part (3) fitted to it from the transport area (33) of the sheet-metal strip, and thus separation of the completely assembled screw connecting terminals.
9. Method according to Claim 8, with the clamping screw being inserted into the clamping part (3) before the latter is pushed onto the busbar (4).
10. Method according to Claim 9, with the clamping screw (2) being tightened until the clamping part (3) is fixed on the busbar (4), before the screw connecting terminals (1, 30) are separated from the sheet-metal strip.

Images