EP2394286A1

EP2394286A1 - Tripping apparatus, particularly for circuit breakers

Info

Publication number: EP2394286A1
Application number: EP10706133A
Authority: EP
Inventors: Matthias Kulke; Jörg GASSMANN; Thomas Müller
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2009-02-05
Filing date: 2010-01-22
Publication date: 2011-12-14
Anticipated expiration: 2030-01-22
Also published as: WO2010088875A1; CN102308355A; EP2394286B1; US8547190B2; DE102009007586A1; CN102308355B; US20120018287A1

Abstract

The invention relates to a tripping apparatus (1), particularly for circuit breakers, which comprises at least one controllable tripping magnet (2) having an armature (2.1) that is operatively connected to a downstream tripping gear (6.3), which engages in a tripping mechanism that acts on the circuit breaker and is coupled to a preloaded spring (4) serving as a force amplifier. According to the invention, the tripping mechanism comprises a camshaft (5) having a plurality of cam lobes (5.1, 5.2, 5.4), wherein an actuating means (6) is associated with each cam lobe (5.1, 5.2, 5.4) having an offset rotational angle, and wherein, when tripped, at least two actuating processes associated with the respective actuating means (6.1, 6.2, 6.3) take place consecutively, so that the full spring force is transmitted by way of the camshaft (5) to at least one of said actuating means (6.1, 6.2, 6.3) so as to perform the relevant actuating process.

Description

Tripping device, in particular for circuit breakers

The invention relates to a tripping device, in particular for circuit breaker, which is at least one controllable trigger magnet with armature, which is in operative connection to a downstream trigger pawl, which is engaged with a force acting on the circuit breaker tripping mechanism, which is coupled to a prestressed spring serving as a power amplifier in engagement , having.

Such power-operated tripping devices are used for the actuation of circuit breakers. The circuit-breakers designed for high currents can not only switch operating currents and low overload currents, but also switch on high overload currents and short-circuit currents in the event of errors, hold these fault currents for a predetermined time and then switch them off again. The overload current refers to the weakest link of the downstream of the circuit breaker, as seen in the direction of energy flow. In order to protect such downstream systems from damage due to overload or short circuit, the circuit breaker should switch off these currents in conjunction with the network protection devices within a defined time.

When the circuit breaker is turned on, energy is stored in a memory, e.g. a spring stored. In order to quickly release this energy in the event of a fault and thus be able to open the contacts of the switch, a very fast-acting release mechanism is needed.

As a magnetic release with power amplification, a mechanism is known from the prior art, which is used in the circuit breaker SUSOL 250A (LS Industrial Systems). The basic principle of magnet-pawl tripping shaft with magnet reset is used here. Of the Release magnet moves a release latch when released with little force. This releases a lever or shaft, which is biased by a stronger, acting as a power amplifier spring. The shaft starts to rotate and at the same time triggers all actuations to be realized, namely trigger the switch lock, press the auxiliary switch and reset the release magnet. Since these adjustments occur simultaneously, the energy of the spring is distributed to all target functions. In each individual setting process masses are accelerated and friction and counter forces are overcome. For each setting so only a part of the currently effective spring force is available. The settling processes are therefore relatively slow. However, a short trip time is indispensable for fast switching and protection of the system from excessive currents.

To achieve a short tripping time, the spring forces, respectively the reinforcing spring and the magnetic spring, must be increased significantly. However, this is associated with a magnet with higher power requirements, which increases the manufacturing cost of such a triggering mechanism sensitive. In addition, these measures require a larger space, which is usually not available.

With the previously known from the prior art solutions, the switching times that are required in modern circuit breakers, sometimes no longer reach. At the same time low-energy actuators are required for actuating the release latch, whereby the spring forces are limited.

The object of the invention now is to propose a tripping device, in particular for circuit breakers, with which the necessary adjusting operations or switching functions can be realized with only small forces within the required switching time. The invention relates to a tripping device, in particular for circuit breaker, which is at least one controllable trigger magnet with armature, which is in operative connection to a downstream trigger pawl which engages with a force acting on the circuit breaker tripping mechanism, which is coupled to a prestressed spring serving as a force amplifier , having. According to the invention, the triggering mechanism comprises a camshaft having a plurality of cams, wherein each rotationally offset cam is associated with an actuating means, and in the triggering case, at least two actuating processes associated with the respective actuating means run sequentially in time, so that on at least one of these actuating means for completing the associated actuating operation, the full spring force over the camshaft is transmitted.

As adjusting operations are in the context of the invention essentially the adjusting process of triggering a switching mechanism by means of the switch lever, the operation of an auxiliary switch preferably using an auxiliary switch pins, the return movement of the trip latch and the provision of the armature of the release provided, the time-critical main function, the triggering of Switch lock, first and at maximum speed expires. To trigger the switching mechanism is thus the full spring force available, which allows higher switching forces and leads to shorter switching times.

Trigger the individual actuating operations, switching mechanism, actuate the auxiliary switch, return the tripping latch and the return of the armature are preferably offset in time. All adjusting operations preferably take place at least partially successively in time, ie sequentially, with a safety period lying between the end of a setting process and the beginning of a subsequent setting process. As a result, the energy transmitted to the camshaft by the spring concentrates on the actuation (s) performed at that time.

The decisive advantage of this invention is therefore that the tripping time of the main function, the triggering of a switching mechanism, compared to previously known solutions can be significantly shortened. The tripping device according to the invention makes better use of the energy of the spring force accumulator and thus requires less electric tripping energy.

The actuating means can perform a linear or rotary adjusting movement. According to the concept of the invention, at least three actuating means are provided, of which a first actuating means as a switch lock lever rotatory adjusting movement, a second actuating means as Hilfsschalterpin a linear actuating movement and a third actuating means as a triggering pawl performs a rotary actuator movement.

In a particularly advantageous embodiment of the invention, designed as a shift lever first actuating means on a curve contour which is designed such that after taking the end position of the switch lever at a conditional by the spring force further rotational movement of the camshaft, the cam lever associated cam slides along the curve contour, wherein the angle of rotation of the camshaft significantly increased without changing the final position of the switch lever. Because of the design of the rotation angle of the shaft is defined for triggering the switching mechanism via its switch lock lever, the rotation angle of the shaft must be increased to allow the other functions to run afterwards. Due to the increased rotation angle of the camshaft, the usable spring travel of the spring is increased and the energy yield at a given maximum force increases sharply, for example to twice.

In a preferred embodiment of the invention, the return movement of the release pawl and the concomitant, but staggered return movement of the armature of the release magnet done only after taking the final position of the switch latch lever.

In order to achieve shorter shift times, designed as a shift lever lever first actuating means has completed its adjustment process completely before further actuation processes are triggered by the cam of the camshaft.

In a preferred embodiment of the invention, the movement of the camshaft is transmitted using a coupling gear to the switching mechanism or its switch lock lever.

The angle between the two spring suspensions and the pivot point of the camshaft according to the invention is chosen so that the spring work at a given angle of rotation of the camshaft is maximum.

Another practice-relevant solution further consists in that at least two triggering mechanisms are provided, which in the direction of action of force one behind the other, d. H. cascaded, are arranged.

It is also essential to the invention that the triggering pawl and a sperm cam each have contours formed according to the principle of stitch point displacement, as a result of which the triggering pawl can be moved with reduced expenditure of force and the latched camshaft is released more quickly. The significant advantages and features of the invention over the prior art are essentially:

■ in the event of triggering, the adjusting operations assigned to the respective actuating means are offset in time, so that in each case the complete spring force is transmitted via the camshaft to each of these actuating means for completing the associated actuating operation,

■ as actuating operations, the triggering of the switching mechanism, the actuation of the auxiliary switch, the return movement of the release latch and the return of the armature of the release magnet are provided, the time-critical main function, the triggering of the switching mechanism, first and at maximum speed,

■ due to the fact that the triggering of the switching mechanism is carried out first as the time-critical setting process, the tripping time can be significantly shortened compared with the solutions known from the prior art,

■ a shorter tripping time is a decisive advantage in the switch design and contributes to the development of smaller and less expensive circuit breakers with the same switching currents,

■ the switch lock lever of the switching mechanism has a curve contour, which is designed such that after taking the end position of the switch lever at a conditional by the spring force further rotational movement of the camshaft, the cam lever associated cam slides along the contour of the curve, wherein the angle of rotation of the camshaft and also the spring travel of the spring significantly increased, so more energy can be obtained from the spring. ■ the rotation angle increase allows a more efficient use of the spring energy and allows the use of weaker, lower-energy release magnets,

^■ the stitch point offset on the release latch and on the locking cam allow the use of weaker, lower-energy release magnets and also increase the triggering speed,

■ Due to the smaller forces to be switched, the required electrical release energy is reduced, which is particularly advantageous for electronic releases that cover their energy requirements via the current transformers of the measuring electronics,

■ The space of the tripping device according to the invention is only slightly increased by the camshaft.

The objectives and advantages of this invention will become better understood and appreciated after a careful study of the following detailed description of the preferred non-limiting example embodiments of the invention herein, together with the accompanying drawings, in which:

Fig. 1: a perspective view of the triggering device in the

Starting position, Fig. 2: a perspective view of the triggering device in the

Intermediate position, Fig. 3: a perspective view of the triggering device in the

Endposition, Fig. 4: a diagram illustrating the path or angle of rotation in

Dependence on the time of all adjustments at the level of

Technology, 5 shows a diagram for illustrating the path or angle of rotation in FIG

Dependent on the time of all adjusting operations in the tripping device according to the invention and Fig. 6 is a comparative diagram of the used

Spring energy in the prior art and in the tripping device according to the invention.

Figures 1 to 3 show a perspective view of the same tripping device 1, in particular for circuit breakers, in the starting position, in the intermediate position, and in the end position. The tripping device 1 according to the invention comprises a controllable triggering magnet 2 with armature 2.1, which is in operative connection with a downstream triggering pawl 6.3, which engages with a tripping mechanism acting on the power switch, which is coupled to a pretensioned spring 4 serving as a power amplifier. As a trigger mechanism according to the invention a camshaft 5 with a plurality of cams 5.1, 5.2, 5.4 is provided. Each placed on the camshaft 5 angle offset cam 5.1, 5.2 and 5.4 is associated with an actuating means 6, wherein in the triggering case at least two the respective actuating means 6.1, 6.2, 6.3 associated actuating processes run sequentially in time, so that on at least one of these actuating means 6.1, 6.2, 6.3 to complete the associated actuating operation, the full spring force is transmitted via the camshaft 5. In the illustrated example, the camshaft 5 comprises three cams 5.1, 5.2 and 5.4. The first cam 5.1 is in this case assigned to a first actuating means 6 designed as a switching mechanism lever 6.1. The rotatably mounted switch lock lever 6.1 according to the invention has a curve contour 3, whose function will be explained in more detail later. By means of the switch lever 6.1, the switching mechanism of a circuit breaker, not shown, is mechanically actuated or triggered. The camshaft 5, the tripping 6.3, the auxiliary switch 6.2 and the trigger magnet 2 are in a not shown Housing stored. The acting on the camshaft 5 and serving as a power amplifier spring 4 is also suspended in this housing. This spring 4 is biased in the initial state. The armature 2.1 of the controllable release magnet 2 is in operative connection with the tripping latch 6.3, which releases a further arranged on the camshaft 5 locking cam 5.3 at extended anchor 2.1, so that the spring 4 can put the camshaft 5 in a rotary motion.

The operation of the tripping device 1 according to the invention is as follows: In the starting position according to FIG. 1, the tripping magnet 2 or its coils are de-energized. The armature 2.1 is located completely within the release magnet 2. The two legs comprehensive release latch 6.3 abuts with one of its two legs on the front side of the armature 2.1. Furthermore, a driving cam 5.4 is arranged next to the locking cam 5.3. For taking the intermediate position shown in FIG. 2, the release magnet 2 is energized and the armature 2.1 moves axially outward. At this time, both the tripping 6.3 and the camshaft 5 remain in their original position. Immediately thereafter, the tripping latch 6.3 is set in rotation and releases the locking cam 5.3 of the camshaft 5 after rotation by a few degrees so that the camshaft 5 is set in rotation by the pretensioned spring 4. This is followed by the first and most important adjusting movement of the triggering device 1, in which the first cam 5.1 sets the switching mechanism lever 6.1 in a rotational movement. Further actuating movements are not carried out at this time. The entire force acting at this time spring force is thus available for this first adjusting movement. The switch lock lever 6.1 is brought in continuous rotational movement of the camshaft 5 in its final position, which is achieved in the example shown by turning to the right by a defined angle. Upon further rotation of the camshaft 5, the first cam 5.1 runs along the curve contour 3 of the switch lever 6.1. During this phase, the cam 5.2 associated with the auxiliary switch pin 5.2 of the camshaft 5 reaches the auxiliary switch pin 6.2, moves it and does not actuate one illustrated auxiliary switch. Immediately after reaching the culmination point of the curve contour 3 of the switch lever 6.1, the provision of the release latch 6.3 and the associated provision of the armature 2.1 of the release magnet begins. 2

The diagrams of Figures 4 and 5 show the path or the angle of rotation of the actuators as a function of time. Fig. 4 depicts the adjusting operations of the prior art; As can be seen, increases in accordance with Fig. 4 in the armature movement and the actuating movement of the tripping 6.3 6.3 initially the way over time progressively. Upon reaching the end position of the release latch 6.3 start in the previously known from the prior art conventional release mechanism, the actuation triggering a switching mechanism and pressing an auxiliary switch. During this phase, the provision of the release latch 6.3 and the associated return of the armature 2.1 of the release magnet 2 takes place. All three or four actuations end almost at the same time. The provided for driving the trigger mechanism spring 4 is during the rotational movement of the camshaft 5 from their spring energy and distributes this at the same time to all three or four actuating operations, connected to the disadvantages mentioned above.

In the tripping device according to the invention according to the figures 1 to 3, however, the spring energy is distributed at different times to the individual actuating operations of FIG. 5 as follows: First, the tripping magnet 2 and its coils is energized and the armature 2.1 moves in the axial direction of the tripping latch 6.3. Just before the anchor 2.1 and the tripping 6.3 have reached their maximum deflection, the pawl releases the camshaft 5. This begins to rotate and drives on her first cam 5.1 exclusively the switch lock lever 6.1. The full spring force is available for this positioning process. Only after reaching the maximum angle of rotation, which the end position of Switch lever 6.1 corresponds to all other settlements are triggered with a time delay. First, the release latch 6.3 is reset, which simultaneously moves the armature 2.1 back to the starting position. Between the time end of the movement of the switching mechanism lever 6.1 and the beginning of the starting shortly thereafter adjusting movement of the second cam 5.2 of the camshaft 5 for actuating the auxiliary switch pins 6.2 and the return movement of the armature 2.1 is a safety period. All of the aforementioned actuating operations, except for the adjusting movement of the switch lever 6.1, but ends almost at the same time. In the overall consideration of Figures 4 and 5 it should be noted that in the tripping device 1 according to the invention over the tripping mechanism of the prior art, a significant time advantage in terms of taking the final position of the switching mechanism 6.1 is recorded. In other words, the switching mechanism acting on the circuit breaker is triggered faster due to the time-delayed starting operations, since the entire spring force is concentrated on the current important process.

FIG. 6 shows a comparative diagram of the utilized spring energy according to the prior art and the tripping device 1 according to the invention under given boundary conditions. In the diagram, the spring energy is plotted against the angle of rotation of the camshaft 5. In the previously known from the prior art solutions, the rotation angle of the trigger shaft is smaller than the rotation angle of the camshaft according to the invention 5. This is associated with the angle of rotation associated, used spring energy, which is lower in the trip shaft of the known solutions than in the camshaft 5 of the inventive solution , The inventive added value corresponds to the available delta ΔE of the usable spring energy. The different angles of rotation of the camshaft 5 according to the invention with respect to the conventional triggering shaft mean that in the invention on the one hand the existing Spring energy can be used more efficiently and on the other hand that the adjustment process of triggering the switching mechanism 6.1 starts both at an earlier date and completed faster. However, the triggering device 1 is reset only after the switch lock lever 6.1 has taken its final position.

LIST OF REFERENCE SIGNS

1 triggering device

2 trigger magnet

2.1 anchor

3 curve contour

4 spring

5 camshaft

5.1 first cam

5.2 second cam

5.3 Spermocke

5.4 Driving cam

6 actuating means

6.1 Shift lever

6.2 auxiliary switch pin

6.3 Release latch

Claims

1. tripping device (1), in particular for circuit breakers, at least comprising a controllable release magnet (2) with armature (2.1), which is in operative connection to a downstream release latch (6.3), which with a force acting on the circuit breaker tripping mechanism with a as Power-operated biased spring (4) is coupled, characterized in that the triggering mechanism comprises a camshaft (5) with a plurality of cams (5.1, 5.2, 5.4), wherein each angle of rotation offset cam (5.1, 5.2, 5.4) each one Actuating means (6) is assigned, and in the triggering case at least two the respective actuating means (6.1, 6.2, 6.3) associated actuating processes run sequentially in time, so that on at least one of these actuating means (6.1, 6.2, 6.3) for completing the associated actuating operation, the full spring force is transmitted via the camshaft (5).

2. triggering device (1) according to claim 1, characterized in that as actuating operations, the triggering of a switching mechanism, the operation of an auxiliary switch, the return movement of the release latch (6.3) and the provision of the armature (2.1) of the release magnet (2) are provided, the time-critical main function triggering a switch lock first and at maximum speed expires.

3. triggering device (1) according to claim 1 or 2, characterized in that the respective actuating operations at least partially in time, ie sequentially, expire, wherein between the end of a parking operation and the beginning of a subsequent setting operation is a safety period.

4. triggering device (1) according to one of claims 1 to 3, characterized in that the actuating means (6.1, 6.2, 6.3) perform a linear or rotary adjusting movement.

5. triggering device (1) according to one of claims 1 to 4, characterized in that at least three actuating means (6) is provided, of which a first actuating means (6) as a switching mechanism lever (6.1) of a switching mechanism, a second actuating means (6) Auxiliary switch pin (6.2) of an auxiliary switch and a third actuating means (6) is designed as a triggering pawl (6.3).

6. triggering device (1) according to one of claims 1 to 5, characterized in that the switching mechanism lever (6.1) formed first actuating means (6) has a cam contour (3) which is designed such that after taking the end position of the switch lever ( 6.1) at a conditional by the spring force further rotational movement of the camshaft (5) the cam lock lever (6.1) associated cam (5.1) along the cam contour (3) slides, wherein the angle of rotation of the camshaft (5) significantly increased without the end position of the switch lever (6.1) changed.

7. triggering device (1) according to one of claims 1 to 6, characterized in that increased by the increased rotation angle of the camshaft (5) of the usable travel and the energy yield at a given maximum force increases sharply, for example, twice.

8. triggering device (1) according to one of claims 1 to 7, characterized in that only after taking the end position of the switch latch lever (6.1), the return movement of the release latch (6.3) and the associated, but staggered return movement of the armature (2.1) of the release magnet (2) take place.

9. triggering device (1) according to one of claims 1 to 8, characterized in that for the purpose of achieving the shortest switching times as the switch lock lever (6.1) formed first actuating means (6) has completed its adjusting operation before further adjusting operations by the cam (5.2 , 5.4) of the camshaft (5) are triggered.

10. tripping device (1) according to one of claims 1 to 9, characterized in that the movement of the camshaft (5) using a coupling gear to the switching mechanism lever (6.1) is transmitted.

11. Tripping device according to one of claims 1 to 10, characterized in that the angle between the two spring suspensions and the pivot point of the camshaft (5) is selected so that the spring work at a given angle of rotation of the camshaft (5) is maximum.

12. triggering device (1) according to one of claims 1 to 11, characterized in that at least two triggering mechanisms are provided, which in succession of force direction, d. H. cascaded, are.

13. triggering device (1) according to one of claims 1 to 12, characterized in that the triggering pawl (6.3) and the locking cam (5.3) each have formed on the principle of Stichpunktversetzung contours, whereby the triggering pawl (6.3) with reduced Force can be moved and the latched cam (5) is released faster.