Connection terminal

Information

  • Patent Grant
  • 6764356
  • Patent Number
    6,764,356
  • Date Filed
    Wednesday, April 24, 2002
    22 years ago
  • Date Issued
    Tuesday, July 20, 2004
    19 years ago
Abstract
A connection terminal for connecting two lines comprises two clamping blocks for receiving and electrically connecting the lines. A receptacle is provided on the connection terminal into which a temperature limiter having at least two terminal legs is insertable and into which two connection elements project, each connection element being connected at its first end to one of the two clamping blocks and being contacted at its second end to an associated terminal leg of an inserted temperature limiter.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a connection terminal for connecting at least two lines, comprising a first clamping block to which a first line can be electrically and mechanically connected and a second clamping block to which a second line can be electrically and mechanically connected.




2. Related Prior Art




Such connection terminals are generally known in the prior art.




These connection terminals are available for example in specialty stores as individual parts and are used for example to connect lamps to electrical lines. For this purpose, such connection terminals normally comprise at least two connection parts each consisting of two clamping blocks of electrically conducting material, which are integrally connected to one another, as well as an insulating casing in which the connection parts are arranged.




Each connection part comprises a retaining through bore as well as threaded bores running transversely thereto. The ends, with their insulation removed, of the lines to be connected are inserted into the retaining bores on either side, and these ends are clamped in the retaining bores by screws screwed into the threaded bores. In this manner, a pair of two lines can be electrically and mechanically coupled by a single connecting part. It is also known to insert several lines at one side in the retaining bore, so that an incoming line can simultaneously be connected with several outgoing lines.




Such connection terminals are generally known as lustre terminals.




On the other hand, such connection terminals are also used for connecting transformers, motors, etc. It is known to configure such connection terminals directly, integrally with the housing of the device to be connected, although the connection terminals can also be formed as separate parts secured to the housing of the electrical device by screws or locking.




It is also known to configure the clamping block not as screw connectors but as insulation displacement connectors, where cutting elements are provided in the retaining bores between which the inserted line is clamped and simultaneously contacted.




A so-called temperature limiter is necessary for safety reasons in numerous electrical devices, which normally comprises a bimetal switch and is connected in series with a supply line of the electrical device, so that the operating current of the electrical device flows through the temperature limiter. The temperature limiter is normally thermally coupled to the electrical device to be protected by the limiter, so that a temperature increase of the electrical device leads to a temperature increase of the temperature limiter.




When the temperature of the electrical device to be protected exceeds an allowable upper limit, a bimetal element disposed in the switch is deformed in a known manner and interrupts the current flow to the electrical device. Depending on the configuration of the temperature limiter, it can be provided with a so-called self-holding function, which ensures that the temperature limiter does not switch on again even after the electrical device has cooled off.




It is also known to provide such temperature limiters with a current dependency, so that they respond additionally or exclusively when a certain current value is exceeded, whereby the electrical device is protected against an excess current.




The mounting of such temperature limiters on an electrical device to be protected, normally by hand, is done independently of the connection of the electrical device itself by means of the above-mentioned connection terminal. Frequently, connecting lines of the temperature limiter must be soldered onto contacts of the electrical device to be protected.




An electrical device is known from DE 195 05 342, in which a receptacle is provided for an encapsulated temperature dependent switching mechanism, which is clamped between an external terminal of the device and a terminal part connected directly to the device. From this document, it is also known to provide a receptacle space at the electrical device into which two connecting elements extend between which the encapsulated temperature dependent switch is clamped. A short circuit plug can also be inserted instead of the temperature dependent switch to test the electrical device during fabrication before mounting the temperature dependent switch.




All of the discussed measures for connecting a temperature dependent switch or temperature limiter to an electrical device to be protected have the disadvantage that they either cannot be automated at all or require complicated manipulations, where, for example, first a short circuit plug is plugged in, removed after testing and then the desired temperature dependent switch is inserted.




SUMMARY OF THE INVENTION




In view of the above, an object of the present invention is to provide a simplified, preferably automated assembly of an electrical device equipped with a temperature limiter, where the solution should have a simple construction.




According to the present invention, this object is essentially solved in that the connection terminal as mentioned at the outset comprises a receptacle into which a temperature limiter comprising at least two terminals, preferably two terminal legs, can be plugged in, and into which two connection elements extend, each being connected at their first end to one of the two clamping blocks and at their second end, preferably automatically, contacting a terminal, preferably an associated terminal leg of a temperature limiter, when plugging in same in the receptacle.




The inventors of the present application have found that surprisingly structural modifications of the connection terminal allow a plug-in contact of the temperature limiter so that a series connection of the temperature limiter between the clamping blocks results by simply plugging in the temperature limiter in the receptacle, so that the temperature limiter can be arranged in series with the supply line of the electrical device. This procedure can be automated, because after wiring the connection element the only additional step is to plug in the temperature limiter. Contacting of the temperature limiter to the connection elements is established for example by the insulation displacement technique, although it is also possible to provide screw clamping means. In this case, after plugging in the temperature limiter in the receptacle, only two screws need be tightened down, which however can also be performed automatically, as is the case with wiring the connection element to the lines.




Furthermore, the new connection element allows a rapid and simple assembly and connection of the temperature limiter by hand, for example when a small lot is to be produced or the devices are produced with a lesser degree of automisation.




The new connection terminal can not only be employed for the protection of transformers, motors, etc., where it is secured to the housing in one way or another, rather it can also be used in various fields where protection by a temperature limiter of a device to be connected is possible retroactively in the simplest manner. For example, it is possible to replace the common lustre terminal on a lighting means with the new connection terminal, which only requires a few hand manipulations. With the new connection terminal including the inserted temperature limiter it is now, for example, possible to protect against overheating lighting means previously unmonitored with respect to their temperature development. As is generally known, the lustre clamps in the housing of the lighting means are frequently arranged directly adjacent to the lamp means, so that an overheating results when the rating of the lamp means is too high, which then leads to an increase in the temperature of the lustre clamp, which can be seen over and again with lustre clamps that are charred or deformed by the effects of heat. If the new connection terminals are used instead of the known lustre clamps, an inadmissibly high temperature has the result that the power supply to the lighting means is shut off by the temperature limiter, so that it cannot be damaged or cause any damage as a result of overheating.




In view of the above, connection terminals of the above-mentioned type are subject of the present invention, which comprise between the two clamping blocks a temperature limiter with any interconnection, also for example by soldering the temperature limiter being connected in series with the clamping blocks. By simply exchanging a lustre clamp or by inserting it into a supply line for this purpose, it is possible with the new connection terminal to equip different electrical devices, even retroactively, with a temperature and/or current monitoring means.




Suitable temperature dependent switches are known from documents DE 196 09 310 A1, DE 197 47 589 A1 and DE 197 52 581, each including arranged within a housing a temperature dependent switching mechanism that can be contacted by means of terminal legs extending from the housing, and that according to the first document mainly shows a dependency from temperature, according to the second document a self-holding function, and according to the third document a current dependency.




It should be mentioned that, in the scope of the present application, “temperature limiter” is, on the one hand, generally to be understood as a temperature dependent switch, which separates an electrical connection when an high temperature and/or excess current arises and which optionally is provided with a self-holding function which prevents a closing of the switch after cooling off, wherein in certain configurations the switch remains open even after shutting off the power source, while in other configurations, the self-holding function is reset when the power supply is turned off and then on again. On the other hand “temperature limiters” is here also to be understood as PTC resistors whose resistance increases with growing temperature, so that a current limitation and, indirectly, a temperature limitation is provided for.




As a matter of course it is also possible to integrate the present connection terminal in power switches or plug sockets, couplings, etc. to prevent an inadmissible heating and/or inadmissible high current through the connected consumers. Advantages result, in particular for use outdoors, for example with a water pump in a pond, a garden lamp or the like, which can be inexpensively and simply protected, also when retrofitted.




In an embodiment, the two connection elements at their second end each comprise a clamp contact for an associated terminal leg of the temperature limiter.




This feature is of advantage with respect to simple assembly, since the temperature limiter must only be plugged in and drawing down of additional screws is not necessary.




According to a further object an interruptable short circuit connection is provided between the two connection elements at their second ends, which preferably is interrupted by an actuator member insertable into the receptacle, this actuator member being either arranged on the temperature limiter or provided as a breaker pin, which is insertable into the receptacle so as not to be removable.




These features are generally of advantage in that the connection terminal can be used without the inserted temperature limiter, where no special short circuit plug need be plugged into the receptacle, but the short circuit connection is provided automatically, so to speak, by the temperature limiter not yet having been inserted.




In this manner, one can decide which temperature limiter is to be assembled just before using the new connection terminal. It is, for example, possible to test the electrical device initially without the temperature limiter and then to plug in the limiter, which also can take place automatically, depending on the specifications just before delivering the device. These measures are also of advantage when the present terminals are used to replace lustre clamps, since the entire wiring and cable connections can first be made and tested before upon choice different temperature limiters can then be inserted. This means that the present connection terminal can be marketed independently of the temperature limiter, where it is naturally also possible to market connection terminals with installed temperature limiters, optionally soldered-in temperature limiters.




A further advantage is that the interruption of the short circuit connection does not require the removal of a short circuit plug or the like, rather it is achieved by an actuator member which can also easily and automatically be inserted. A particular advantage is achieved when the actuator member is arranged on the temperature limiter, as then only a single hand manipulation is necessary to simultaneously interrupt the short circuit connection and install the temperature limiter.




The breaker pin has the further advantage that it fulfills special safety requirements when configured to be non-removable. A connection terminal once having been equipped with a temperature limiter can then no more be operated without the temperature limiter, so that a device supplied with power via the connection terminal and to be protected by the inserted temperature limiter can only be supplied with power when the temperature limiter is in place. Should the temperature limiter fall out or be deliberately removed, the device is no longer be supplied with power, so that a high degree of safety with respect to monitoring of the temperature and current is guaranteed. The breaker pin can, for example, be locked in the receptacle for this purpose.




According to a further object, the breaker pin is insertable into the receptacle in a force fit, which can be achieved for example when it has a zero tolerance or a slightly larger dimension with respect to the receptacle.




In this very simple constructive manner, it is ensured that the breaker pin cannot be removed or removed only by destroying the connection terminal.




It will be understood however that the temperature limiter can be exchanged, should it be defective or be exchanged with another temperature limiter with other specifications, for example another response temperature.




It is a further object that the short circuit connection comprises a short circuit element clamped between the connection elements and being movable to an open position by the actuator member.




Also this feature is constructively preferred as it is only necessary to provide a resilient part on one connection element, which is biased onto the other connection element and lifted thereoff by the actuator member. The resilient part can be broken or broken off by the actuator member, so that reestablishing the short circuit connection is excluded. Alternatively, it is also possible to provide the short circuit means as a connector block, which is pushed out of the gap between the two connection elements by the actuator member and optionally urged into a clamp seat from which it cannot be removed, so that an inadvertent closing of the short circuit connection is not possible.




It is a further object that the two connection elements each comprise at least one resilient element and the two resilient elements contact one another to establish the short circuit connection and can be separated from one another by the actuator member.




This has the advantage that two resilient elements contribute to the quality of the short circuit connection, so that a very reliable short circuit connection exists between the clamping blocks before inserting the temperature limiter.




According to a further object each resilient element comprises a first contact region through which it forms the short circuit connection with the first contact region of the other resilient element, and a second contact region through which it contacts an associated terminal leg of a temperature limiter when inserted in the receptacle.




Also this measure is constructively advantageous because each connector element requires only one resilient element which establishes either the short circuit connection or the contact to the temperature limiter. A further advantage apart from the simple construction is that an inserted temperature limiter cannot be bypassed again by inadvertently closing the short circuit connection because the resilient elements can only contact one another or the terminal legs of the temperature limiter.




According to a further object the two connection elements at their respective first end are spring biased into contact with the respective clamping block, where preferably at least one of the clamping blocks comprises a retaining bore for receiving a line as well as a threaded hole running transversely to the bore for a screw for clamping the line in the retaining bore, where preferably the two connection elements on their respective first ends comprise an up-standing resilient wing, which extends approximately parallel to the respective screw and is spring biased onto the screw.




These measures are advantageous in that convential clamping blocks can be used, as are known from the common lustre clamps. Contact results through the connection elements which are either resiliently urged onto the clamping block itself or are urged with their wing onto the clamping screw for the line. An advantage of the wing is also that it can compensate for different geometries of the screw, where the contact further is not impaired when lines of different thickness are clamped in the retaining bore, i.e. when the screw is screwed into the threaded hole at different depths to clamp the line or lines.




It is another object that the connection terminal comprises at least one connection part having two clamping blocks directly connected to one another, through which two further lines can be directly connected to one another.




The advantage is that the present connection terminal can connect two lines directly with one another, while two further lines are connected to one another in series connection with the temperature limiter. The inventors of the present application have found that it is not necessary to provide a temperature limiter in every supply line of the electrical device, although this can naturally be of advantage in certain requirement circumstances, for example when a current dependent temperature limiter without the self-holding function and additionally a temperature limiter responding solely to high temperatures with self-holding function are to be used simultaneously.




According to a further object the connection terminal comprises an insulating casing in which the first and second clamping blocks are arranged at a first side and the connecting part is arranged at a second side and the receptacle is arranged between the two sides.




This allows a geometry such that the temperature limiter is located so to speak in the middle of the connection terminal, where naturally a location at the side is also possible.




According to another object the connection terminal comprises an insulating casing having a first casing section receiving the first and second clamping block and at least one second casing section receiving the at least one connection part, where a flexible spacer is provided between the two casing sections such that the two casing sections are variable in their spacing laterally to one another.




This measure has the advantage that the new connection terminal can also be used to connect at least two pairs of lines, where at least the lines on one side of the connection terminal have a fixed distance between one another with certain tolerances. Due to the fact that the spacing of the clamping blocks laterally with respect to one another can be varied within certain limits, the new connection terminal can be applied to lines whose spacing changes with respect to one another due to the accuracy in fabrication or due to different designs. In the simplest case, flexible or elastic bridges are formed between the casing sections, which are configured to have a zig-zag form, meander form, a wave-like form or the like. In a preferred embodiment, two bridges are provided to form a diamond, where the diamond allows an increase or decrease of the lateral spacing.




With a connection terminal being also subject of the present invention, i.e. having a temperature limiter with arbitrary interconnections between two clamping blocks to which it is connected in series, it is preferred that the temperature limiter comprises two terminal legs that are directly electrically connected at their respective free ends to a respective one of both clamping blocks.




It is an advantage of this measure that it is constructively very simple; both connection elements may be dispensed with if the connection terminal is durably equipped with a temperature limiter.




It is a further object that at least one terminal leg comprises at its free end a fish joint strip that contacts the associated clamping block from the outside.




Here, the simple and safe assembly is advantageous, particularly if the fish joint strip is clamped between the clamping block and an inner wall of a channel of the connection terminal wherein the channel receives the clamping block. Here it is merely necessary to attach a temperature limiter after the clamping block has been inserted into the channel, whereby the fish joint strip slides between the clamping block and the channel wall and gets clamped in this position.




On the other hand, it is an object that at least one terminal leg comprises at its free end a connector eyelet that is connected with the associated clamping block by a screw being provided for clamping one of both lines.




This measure results in a very safe electrical connection between the clamping block and the terminal leg, particularly in those cases wherein the connector eyelet has a smaller diameter than the core diameter at the screw bolt so that the screw screws or even cuts into the connector eyelet and ensures in this way a safe electrical connection between the connector eyelet and the screw. The screw is screwed simultaneously into the clamping block where it is used for clamping a line. Independent from the thickness of the line, the electrical connection between the clamping block and the temperature limiter via the screw is guaranteed, the screw being electrically conductive and being connected on the one side with the clamping block and on the other side with the connector eyelet.




It is also an object that both clamping blocks are arranged along a longitudinal axis one after another and the temperature limiter is received in a frontal receptacle extending transversely to the longitudinal axis.




This measure is advantageous in that the temperature limiter can be thermally coupled to a device to be monitored in a very effective manner. If the electrical device to be monitored is, for example, an electrical motor winding, the clamping block can be directly attached with its front end onto the windings, whereby the temperature limiter is electrically isolated from the windings merely by the outer wall of the casing of the connection terminal, but apart from that the temperature limiter is in close thermal connection to the windings. Thus an effective and fast response is provided for.




The invention further relates to an electrical device provided with a new connection terminal, where the connection terminal is fixed to the housing of the electrical device or alternatively, the connection terminal is formed integrally with the housing.




Further, the invention relates to a temperature limiter with an actuator member arranged thereon or an actuator member independent of the temperature limiter for use in the new connection terminal.




Further advantages and features will become apparent from the following description and the attached drawings.




It will be understood that the above-mentioned features and those to be discussed below are not only applicable in the given combinations but may also be used in other combinations or taken alone without departing from the scope of the present invention.











BRIEF DESCRIPTION OF THE DRAWINGS




Embodiments of the invention are shown in the attached drawings and will be discussed in more detail below. In the drawings:





FIG. 1

shows a schematic plan view of an electric device with a new connection terminal;





FIG. 2

shows a perspective exploded view of the connection terminal of

FIG. 1

in a first embodiment;





FIG. 3

shows a schematic side view of the new connection terminal in a second embodiment with a short circuit arrangement;





FIG. 4

shows an illustration as in

FIG. 3

, however with another embodiment of the short circuit arrangement;





FIG. 5

shows a schematic exploded representation as in

FIG. 2

, however in an embodiment with a short circuit arrangement;





FIG. 6

shows a plan view of the connection terminal of

FIG. 5

, but only in the region of the receptacle and the separated clamping blocks;





FIG. 7

shows a cross-sectional view of the connection terminal of

FIG. 6

along the line VII—VII in

FIG. 6

but with inserted temperature limiter;





FIG. 8

shows a view as in

FIG. 7

but without temperature limiter;





FIG. 9

shows a schematic exploded view as in

FIG. 5

with an actuator member fixed to the temperature limiter;





FIG. 10

shows a cross-sectional view of a connection terminal in a third embodiment seen along the line X—X in

FIG. 13

;





FIG. 11

shows a view as in

FIG. 10

but with a temperature limiter inserted;





FIG. 12

shows a cross-sectional view of the temperature limiter in

FIG. 13

; seen along the line XII—XII of

FIG. 13

;





FIG. 13

shows a plan view of a connection terminal in a fourth embodiment;





FIG. 14

shows a plan view of a connection terminal as in

FIG. 2

but with a receptacle arranged at the centre;





FIG. 15

shows a cross-sectional view of the connection terminal of

FIG. 14

; seen along the line XIV—XIV in

FIG. 14

;





FIG. 16

shows a bottom view of the casing in

FIG. 2

;





FIG. 17

shows a further embodiment of the invention in a view as in

FIG. 2

with the temperature limiter being connected via fish joint strips with the clamping blocks; and





FIG. 18

shows a further embodiment in a view as in

FIG. 17

with a temperature monitor being screwed to the clamping blocks via connector eyelets.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




In

FIG. 1

with the reference numeral


10


, an electrical device


11


is shown schematically, a connection terminal


12


being secured on the also schematically indicated housing


11


of the electrical device.




The connection terminal


12


comprises a first clamping block


14


and separated therefrom a second clamping block


15


. A line


17


is inserted into the clamping block


14


from the left side with its end


16


having the insulation been removed while a line


18


is inserted from the right side into the clamping block


15


. The lines


17


,


18


are mechanically and electrically connected to the clamping blocks


14


,


15


through screws


19


as is known per se.




Two connection parts


21


,


22


are insulatedly arranged adjacent the clamping blocks


14


,


15


, each connection part comprising two clamping blocks connected to one another so to speak integrally, so that lines


23


,


24


or lines


25


,


26


are mechanically received and held and are electrically connected to one another.




The connection terminal


12


so far corresponds to the common lustre terminal through which external lines


17


,


23


,


25


can be connected to internal lines


18


,


24


,


26


of an electrical device


10


, a substantial difference being that the clamping blocks


14


,


15


are not formed integrally with each other but are arranged isolated from one another.




It is also noted that an electric consumer


27


is connected between the lines


18


,


24


and indicated as a load L. The line


26


is connected to ground


28


.




A receptacle


31


for a temperature limiter


32


is provided between the clamping blocks


14


,


15


, as described for example in the above-mentioned documents. Only as an example, the temperature limiter is indicated in

FIG. 1

as to comprise a bimetal spring


33


, which when heated is deformed in the direction of an arrow


34


. As long as the bimetal spring


33


is in the position shown in

FIG. 1

, it provides for an electrical connection between the clamping blocks


14


,


15


and thus for a possible current flow from line


17


over line


18


and to the consumer


27


and from there back via line


24


, connection part


22


, and line


23


.




As mentioned above, a protection of the consumer


27


, i.e. the device


10


, against high temperatures and/or excessive current is achieved by the temperature limiter


32


. The connection terminal


12


can be an integral part of the housing


11


or can be fixed to the housing


11


with screws or locking means. However, it is also possible to place the connection terminal


12


directly in a line, optionally a multi-wire line, without the connection terminal being mechanically fixed to the housing


11


.




The connection terminal


12


of

FIG. 1

is illustrated in

FIG. 2

in a schematic and exploded representation. In

FIG. 1

it can be seen first of all that in known manner the clamping blocks


14


,


15


as well as the connection part


22


comprise retaining through bores


35


along the longitudinal axis, threaded holes


36


running transversely to the bores


35


, in which threaded holes screws


19


can be screwed to clamp and electrically contact the lines inserted into the retaining bores


35


. It will be understood that it is also possible to use insulation displacement clamps instead of the known screw clamps, which do not require screws but have cutting teeth in the retaining bores


35


for mechanical retention and electrical contact with the lines.




The clamping blocks


14


,


15


as well as the connection part


22


are inserted in channels


37


,


38


, which are arranged in elongated, block-like sections


37




a


,


38




a


of an insulating casing


39


. A cuboid


40


is formed at the casing section


37




a


of the channel


37


in which the receptacle


31


is provided.




In addition, the insulating casing


39


comprises screw holes


41


,


42


running transversely to the channels


37


,


38


through which the screws can be screwed into the threaded holes


36


after the clamping blocks


14


,


15


as well as the connecting part


22


are inserted into the corresponding channels


37


,


38


. It is thus prevented that the clamping blocks


14


,


15


as well as the connecting part


22


can fall out of the channels


37


,


38


again.




A cover


43


is also shown at the top in

FIG. 2

, which closes the receptacle


31


on the upper side after the temperature limiter


32


together with the connection elements


44


to be discussed below have been inserted.




Each connection element


44


comprises an upward standing, resilient wing


46


at its first end


45


, which extends parallel to the respective screw


19


and is resiliently biased onto the screw. A contact ring


47


is also provided between the wing


46


and the first end


45


, through which ring the screw


19


is passed to hold the connection element


44


in the receptacle


31


.




The connection element


44


comprises a clamp contact


49


at its second end


48


, which lies in a plane with a base plate


50


of the connection element


44


, the first end


45


extending transversely from the base plate.




When the two connection elements


44


have been inserted into the receptacle


31


, they contact the screws


19


and thus the clamping blocks


14


and


15


through their first ends


45


or the respective wing


46


and contact ring


47


. With their second ends


38


, the connection elements


44


with their clamp contacts


49


are contacted with terminal legs


51


of the temperature limiter, the terminal legs


51


being passed into the U-shaped clamp contacts


49


when the temperature limiter


19


is inserted into the receptacle


31


.




Except for the temperature limiter


32


, the connection terminal


12


can be preassembled and already wired to the electrical device, before then a suitable temperature limiter


32


, depending on the desired cut-off temperature and/or cut-off current, is inserted into the receptacle


31


, preferably with an automatic handling device. If desired, the receptacle


31


can then be closed with the cover


43


.




The connection terminal


12


of

FIG. 1

is shown in a second embodiment in

FIG. 3

, where a short circuit connection


52


in the form of a resilient short circuit element


53


is provided between the schematically indicated connection elements


44


. In this manner, the clamping blocks


14


,


15


are conductively connected to one another when no temperature limiter


32


is inserted in the receptacle


31


.




An actuator member


54


is provided on the temperature limiter


32


and pushes the resilient short circuit element


53


in the direction of an arrow


55


away from the right connection element


44


, so that the short circuit connection


52


is interrupted. When inserting the temperature limiter


32


, its legs


51


engage with the connection elements


44


, which aside from the clamp contacts shown in

FIG. 2

can also be formed as insulation displacement clamps or screw clamps.




A similar construction to

FIG. 3

is shown in

FIG. 4

, however, the short circuit connection


52


is formed as a short circuit block


56


which is pushed by the actuator member


54


in the direction of an arrow


57


out of the space between the connection elements


44


into a clamp pocket


58


, where it is held in captive manner.




While in the embodiment of

FIG. 3

, if need be, the short circuit connection


52


is closed again when the temperature limiter


32


is withdrawn, the interruption of the short circuit connection


52


in

FIG. 4

is irreversible, which is frequently desired when greater safety is required. Namely, when the short circuit connection


52


is not closed after the temperature limiter is removed or inadvertently falls out, then it is ensured that an “unprotected” operation of the electrical device is not possible.




Similarly to

FIG. 2

,

FIG. 5

shows an embodiment of the connection terminal where the actuator member is provided as a breaker pin


59


with an arrow head


61


, which is separate from the temperature limiter


32


. A guide channel


62


is provided in the receptacle


31


for the breaker pin


59


, which channel runs transversely but parallel to the longitudinal axis of the receptacle


31


and captively holds the breaker pin


59


in a force fit connection.




Each connection element


44


is configured at its first end


45


as with the connection terminal


12


of

FIG. 2

, in the region of its second end


48


, each connection element


44


however comprises a U-shaped spring element


63


, which forms the short circuit connection


52


and also provides contact to the terminal legs


51


of the temperature limiter


32


.





FIG. 6

shows a plan view of the connection terminal


12


of

FIG. 5

, where the region associated with the connection part


22


is left out for simplification. It is also contemplated that the connection terminal


12


can be configured without the connection part


22


, the insulating casing


39


then having a more narrow construction.




As can be seen in the plan view of

FIG. 6

, each connection element


44


again comprises the wing


46


, the contact ring


47


and now also the two spring elements


63


. The guide channel


62


for the breaker pin


59


extends transversely to the spring element


63


.





FIG. 7

shows a cross-section along the line VII—VII in

FIG. 6

, where a temperature limiter


32


is inserted into the receptacle


31


. As can be seen in

FIG. 7

, the arrow head


61


urges the two spring elements


63


apart from one another, so that the short circuit connection is opened, however contact is established to the terminal legs


51


of the temperature limiter


32


at the same time.




In

FIG. 8

, an illustration as in

FIG. 7

, but without temperature limiter


32


, one can see that each U-shaped spring element comprises a first contact region


64


and a second contact region


65


. In the position shown in

FIG. 8

, the first contact regions


64


of the spring elements


63


contact one another and thus form a short circuit connection, which directly connects the two clamping blocks


14


,


15


with each other.




If the breaker pin


39


is now inserted, its arrow head


61


pushes the two spring elements


63


apart and the short circuit connection is broken. The temperature limiter


32


is inserted simultaneously with the breaker pin


59


or shortly thereafter, the terminal legs


51


of the temperature limiter


32


then resting against the two contact regions


65


of the spring elements


63


.




Returning to

FIG. 6

, it can be seen that the two contact regions


65


are displaced with respect to one another in the plane of the drawing of FIG.


6


. This accounts for the arrangement of the terminal legs


51


, which are also displaced as can also be seen in FIG.


5


.




While standard temperature limiter


32


can be employed in the embodiment of

FIG. 5

, in the embodiment of

FIG. 9

a temperature limiter


32


is employed having the arrow head


61


arranged directly thereon. Otherwise, the connection terminal


12


of

FIG. 9

corresponds to the embodiment of FIG.


5


.




In

FIGS. 7 and 8

, bushing


67


and pin


68


can be seen below the cover


43


, through which the cover


43


is secured to the insulating casing


39


.




While in the embodiments of

FIGS. 5 and 9

, the spring elements


63


provide for both the short circuit connection


52


and also for the contact to the terminal legs


51


of the temperature limiter


32


, in the embodiments of

FIGS. 10

to


13


the connection elements


44


are comparable to the spring elements of

FIG. 2

, where the contact to the terminal legs


51


takes place through the U-shaped clamp contacts


49


. In addition, the connection elements


44


in

FIGS. 10

to


13


comprise spring brackets


71


which contact one another when the temperature limiter


32


is not inserted and thus form the short circuit connection


52


, as shown in FIG.


10


.




As can be seen from

FIG. 11

, an inserted temperature limiter


32


with the arrow head


61


in this case fixed thereto pushes apart the spring brackets


71


, so that the short circuit connection


52


is interrupted. At the same time, the terminal legs


51


engage in the clamp contacts


49


as can best seen in the cross-sectional view of FIG.


12


. In this view it can also be seen how the screw


19


sits in the screw hole


42


, the screw being connected to the connection element


44


by the contact ring


47


. The wings


46


can be seen in the plan view of FIG.


13


. The displaced arrangement of the two clamp contacts


49


as well as the centrally formed short circuit path


52


can also be seen here.





FIGS. 14 and 15

show a plan view and a cross sectional view, respectively, of a further embodiment of the connection terminal, where the clamping blocks


14


,


15


are provided on a first side


73


and a connection part


22


is provided on a second side


74


, the receptacle


31


being arranged between the two sides


73


,


74


, which receptacle in the previous embodiments was always located at the side


73


. A gap


75


is formed in the insulating casing


39


due to the arrangement shown in

FIGS. 14 and 15

.




As can be seen in

FIG. 15

, lower guide channels


76


are provided on the insulating casing


39


through which the connection terminal


12


can be secured to a housing


11


of an electrical device


10


to be protected.




Finally,

FIG. 16

shows a bottom view of the insulating casing


39


of

FIG. 2

, where in contrast to the embodiment of

FIG. 15

, the receptacle


31


is not located between the casing sections


37




a


,


37




b


, but in the cuboid


40


at the left side of the casing section


37




a.






As can be seen in

FIG. 16

, the channels


37


,


38


run in longitudinal direction, indicated at


81


, of the rectangular shaped casing sections


37




a


,


38




a


, where a spacing


82


is formed transversely to the longitudinal direction


81


between the two casing sections


37




a


,


38




a


. This spacing


82


is spanned by a flexible spacer


83


, which connects the two casing sections


37




a


,


38




a


with one another such that the spacing


82


can be made larger or smaller.




In the illustrated embodiment of

FIG. 16

, the spacer


83


comprises two webs


84


, which form a kind of a diamond shape and their tips


85


,


86


point away from one another in the longitudinal direction


81


. When the spacing


82


is altered, the tips


85


,


86


move correspondingly toward or away from one another. It will be understood that several such spacers


83


can be provided between the casing sections


37




a


,


38




a.






With the flexible variation of the spacing


82


, the connection terminal


12


can be used to connect lines


17


,


23


, whose spacing


87


varies due to manufacturing tolerances or the type of construction. Thus only one connection terminal


12


is necessary to be able to connect lines


17


,


23


having different spacings


87


.




Should the connection terminal


12


be designed to connect three pairs of lines, as indicated schematically in

FIG. 1

, a further casing section can be provided to the right of the section


38




a


, which can then also be connected to the casing section


38




a


with a flexible or deformable spacer.





FIG. 17

shows a further embodiment of the new connection terminal in an exploded view as in

FIG. 2

, where the same parts are indicated with the same reference numerals.




Each free end


91


of the terminal legs


51


of the temperature limiter


32


comprises a fish joint strip


92


that engage into slots


93


at the insulating casing


39


during insertion of the temperature limiter


32


so that they protrude into the channel


37


. Beforehand, the clamping blocks


14


,


15


are inserted into channel


37


so that the fish joint strips


32


are clamped between an inner wall


94


of channel


37


and an outer wall


95


of the respective clamping block


14


,


15


, thus establishing an electrical contact of the temperature limiter


32


to both clamping blocks


14


,


15


that are electrically connected in this way.




In the channel


37


the clamping blocks


14


,


15


are arranged along a longitudinal direction indicated by


96


. In the embodiment as shown in

FIG. 17

the receptacle


31


is located at the front end of the insulating casing


39


so that it extends transversely to the longitudinal direction


96


.




At the bottom of

FIG. 17

the connection terminal


12


is shown with mounted temperature limiter


32


. Arrow


97


indicates where connection terminal


12


rests on an electrical device to be protected, namely with a front wall


98


that electrically separates the temperature limiter


32


from the device to be protected, but has only a small thickness so that, in toto, a good thermal coupling of the temperature limiter


32


to the device is achieved.





FIG. 18

shows the connection terminal


12


in a comparable embodiment as in

FIG. 17

, only the connection between the clamping blocks


14


,


15


and the terminal legs


51


of the temperature limiter


32


is established in a different manner. As in

FIG. 17

, the terminal legs


51


are bent several times, but now their free ends


51


bear connector eyelets


99


that are placed in the two screw holes


41


in the frontal receptacle


31


during insertion of the temperature limiter


32


.




The screws


19


are screwed through the screw holes


41


, thereby passing through the eylets


91


and screwing into the clamping blocks


14


,


15


. The connector eyelets


99


have an inside diameter that is smaller than the diameter of the core of the thread of screws


19


so that the screws firmly cut into the connector eyelets


99


and therefore provide for good electrical connection between the screws and the terminal legs


51


. When the screws are screwed into the clamping blocks


14


,


15


, an electrically conductive connection between the two clamping blocks


14


,


15


through the screwed-in screws


19


, the connector eyelets


99


and the temperature limiter


32


is achieved.



Claims
  • 1. A connection terminal for connecting at least two lines, comprising a first clamping block to which a first line can be electrically and mechanically connected and a second clamping block to which a second line can be electrically and mechanically connected, wherein a receptacle is provided into which a temperature limiter comprising at least two terminals can be plugged in, and into which two connection elements extend, each being connected at its first end with one of the two clamping blocks and at its second end in contact with an associated terminal of a temperature limiter, when plugging in same in the receptacle, wherein an interruptable short circuit connection is provided between the two connection elements at their second ends, such that said second ends are interconnected with each other either via said short circuit connection or via said temperature limiter; and further comprising at least one connection cart having two clamping blocks directly connected to one another, through which two further lines can be directly connected to one another, and an insulating casing having a first casing section receiving the first and second clamping block and at least one second casing section receiving the at least one connection part, wherein a flexible spacer is provided between the two casino sections such that the two casing sections are laterally variable in their spacing to one another.
  • 2. The connection terminal of claim 1, wherein the two connection elements at their second end each comprise a clamp contact for an associated terminal leg of the temperature limiter.
  • 3. The connection terminal of claim 1, wherein at least one of the two clamping blocks comprises a retaining bore for receiving a line as well as a threaded hole running transversely to the retaining bore and provided for a screw for clamping the line in the retaining bore.
  • 4. The connection terminal of claim 1, wherein the first and second clamping blocks are arranged in the insulating casing at a first side and the connection part is arranged at a second side, whereby the receptacle is arranged between the two sides.
  • 5. The connection terminal of claim 1, wherein both clamping blocks are arranged along a longitudinal axis one after another and that the temperature limiter is received in a frontal receptacle extending transversely to the longitudinal axis.
  • 6. The connection terminal of claim 1, wherein the temperature limiter is a PTC-element.
  • 7. The connection terminal of claim 1, wherein the temperature limiter is a bimetal switch.
  • 8. The connection terminal of claim 1, wherein the two connection elements each comprise at least one resilient element and the two resilient elements contact one another to establish the short circuit connection and can be separated from one another by the actuator member.
  • 9. The connection terminal of claim 8, wherein each resilient element comprises a first contact region through which it forms the short circuit connection with the first contact region of the other resilient element, and a second contact region through which it rests against an associated terminal leg of a temperature limiter inserted into the receptacle.
  • 10. The connection terminal of claim 1, wherein the short circuit connection comprises a short circuit element clamped between the connection elements and being movable into an open position by the actuator member.
  • 11. A temperature limiter having an actuator member arranged thereon for use in a connection terminal according to claim 10.
  • 12. An actuator member for use in a connector terminal according to claim 10.
  • 13. The connection terminal of claim 1, wherein the two connection elements at their respective first ends are spring biased to rest against the respective clamping block.
  • 14. The connection terminal of claim 13, wherein at least one of the two clamping blocks comprises a retaining bore for receiving a line as well as a threaded hole running transversely to the retaining bore and provided for a screw for clamping the line in the retaining bore.
  • 15. The connection terminal of claim 14, wherein the connection elements each comprise an upstanding, resilient wing at its first end, which wing extends approximately parallel to the respective screw and rests under spring bias onto the screw.
  • 16. An electrical device having a connection terminal according to claim 1.
  • 17. The electrical device of claim 16, wherein the connection terminal is secured on its housing.
  • 18. The electrical device of claim 16, wherein the connection terminal with its insulating casing is formed integrally with the housing.
  • 19. The connection terminal of claim 1, wherein the short circuit connection can be interrupted by an actuator member insertable into the receptacle.
  • 20. An actuator member for use in a connector terminal according to claim 19.
  • 21. The connection terminal of claim 19, wherein the actuator member is arranged on the temperature limiter.
  • 22. A temperature limiter having an actuator member arranged thereon for use in a connection terminal according to claim 21.
  • 23. The connection terminal of claim 19, wherein the actuator member is a breaker pin which is insertable into the receptacle so as not to be removable.
  • 24. The connection terminal of claim 23, wherein the breaker pin is insertable into the receptacle in a force fit.
  • 25. A connection terminal for connecting at least two lines, comprising a first clamping block to which a first line can be electrically and mechanically connected and a second clamping block to which a second line can be electrically and mechanically connected, wherein a receptacle is provided into which a temperature limiter comprising at least two terminals, preferably two terminal legs, can be plugged in, and into which two connection elements extend, each being connected at its first end with one of the two clamping blocks and at its second end, preferably automatically, contact a terminal, preferably an associated terminal leg of a temperature limiter, when plugging in same in the receptacle, comprising at least one connection part having two clamping blocks directly connected to one another, through which two further lines can be directly connected to one another, and comprising an insulating casing having a first casing section receiving the first and second clamping block and at least one second casing section receiving the at least one connection part, wherein a flexible spacer is provided between the two casing sections such that the two casing sections are laterally variable in their spacing to one another.
  • 26. An electrical device having a connection terminal according to claim 25.
  • 27. The electrical device of claim 26, wherein the connection terminal is secured on its housing.
  • 28. The electrical device of claim 26, wherein the connection terminal with its insulating casing is formed integrally with the housing.
Priority Claims (2)
Number Date Country Kind
199 51 815 Oct 1999 DE
199 53 954 Nov 1999 DE
RELATED APPLICATION

This is a continuation application of International Patent Application PCT/EP00/10563 filed Oct. 26, 2000 published as WO 01/31749.

US Referenced Citations (9)
Number Name Date Kind
3533054 Spriggs et al. Oct 1970 A
3750082 Petersen et al. Jul 1973 A
3826000 Du Rocher Jul 1974 A
5717257 Hofsäss Feb 1998 A
5864278 Becher Jan 1999 A
5897389 Ditz et al. Apr 1999 A
6004159 Liang Dec 1999 A
6031447 Hofsäss Feb 2000 A
6091316 Hofsäss Jul 2000 A
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Number Date Country
30 06 311 Aug 1981 DE
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85 15 405 Sep 1985 DE
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196 09 310 Nov 1997 DE
197 19 788 Nov 1998 DE
197 48 589 Sep 1999 DE
197 52 581 Dec 1999 DE
1 272 775 May 1972 GB
1 540 685 Feb 1979 GB
Non-Patent Literature Citations (1)
Entry
Phoenix Contact: “Erste Verbindungstechnik 93/94”, Phoenix Contact GmbH, Blomberg, DNR. 895-4/93, pages 116,117 119.
Continuations (1)
Number Date Country
Parent PCT/EP00/10563 Oct 2000 US
Child 10/131671 US