EP0721647A1 - DEVICE FOR CONTROLLING THE SWITCHING OF A CIRCUIT BREAKER - Google Patents

Abstract

A power circuit breaker (1) is provided with an arrangement that controls its switching depending on functions' parameters (A...E, M1, M2, S). These parameters may for example be the position of switching contacts, the state of excitation of an undervoltage circuit-breaker and the switching position of another power circuit breaker. The arrangement has a coupling shaft (32) that may be rotated by a tripping half-wave by means of a steering lever (34) and by certain parameters by means of a sensor lever (36). A coupling member (20) that may be swivelled by the coupling shaft (32) allows a ratchet device (5, 6) of the energy storage (7) of the power circuit breaker (1) to be released only when all conditions required for switching are met.

Description

description

Device for controlling the opening of a circuit breaker

The invention relates to a device for controlling the switching on of a circuit breaker as a function of operational parameters, the circuit breaker having switch contacts which can be moved relative to one another and an energy store serving to actuate the switch contacts, and a latching device by means of which the energy store can be latched in the charged state and by hand or can be released remotely, - the operational parameters and an ON command are in the form of a mechanical movement, and - the switch contacts can be moved from the closed state by actuating a trigger shaft to the open state.

Devices of this type are known both in mechanical and in electrical or electronic design (US-A-4 506 246, US-A-2 640 122, DE-A-38 06 370). The functions that are achieved with the known devices include, in particular, the prevention of empty circuits and the so-called pumping. These processes place a heavy load on the switching technology of a circuit breaker and are therefore detrimental to its service life.

The invention is based on the object of realizing a device of the type mentioned at the outset with means which are inevitably effective and therefore operable without auxiliary energy and, in addition to the undesired processes mentioned, include further operational aspects which are desired for safe operation of the circuit breaker in the device. This object is achieved according to the invention by means of a common coupling shaft for OR operation parameters and a coupling element which can be actuated by the coupling shaft for transmitting an ON command to the latching device. The clutch shaft namely offers an advantageous way, any influences, for. B. to take into account the lack of a release to be inserted as a structural unit in the circuit breaker or the lack of excitation of an undervoltage release. Whenever there is a condition on the basis of which the circuit breaker is to be prevented from opening, the coupling shaft disengages the coupling element from the latching device. An ON command, regardless of whether it is given by hand or by an electromagnet, remains ineffective.

In an advantageous embodiment of the invention, the

Features include:

The latching device has a locking shaft and a driver pin connected to the locking shaft, the coupling member has a coupling lever which can be pivoted about a pivot bearing and which is provided with a coupling pin which detects the driver pin, the pivot bearing is located on a pivotably mounted and by an Command actuatable lever carrier, wherein an actuation of the lever carrier corresponds to a displacement of the pivot bearing of the clutch lever in the sense of a rotation of the locking shaft to release the energy store and the lever is pivotable by the clutch shaft about its pivot bearing in order to engage or disengage the coupling pin from the driving pin bring.

The coupling shaft can be provided with one or more sensing levers, the operational parameters that arise for scanning inside and outside the circuit breaker These parameters can in particular be "position of the switch contacts of the circuit breaker", "presence of an overcurrent release", "switch position of at least one further circuit breaker", "position of the door of a circuit breaker receiving the circuit breaker" and "state of the travel drive of the circuit breaker in a rack ".

In any case, a lack of readiness to switch on should be signaled when a trigger command is present. This can be achieved in that a release half-shaft belonging to the switch-off latch has an extension arm and that the coupling shaft carries a steering lever which interacts with the extension arm in such a way that when the release half-shaft is acted upon, the clutch shaft is also rotated in the release direction by to bring the coupling pin out of engagement with the driver pin. This arrangement ensures that all the organs provided for triggering the circuit breaker also cause the message or display "not ready to be switched on". In particular, the tripping half-wave of the parameters "lack of excitation of an undervoltage release" can be supplied.

In the device according to the invention, the aforementioned empty switching and pump prevention can be implemented in a particularly simple manner in that the position of a switching shaft actuating the switching contacts can be supplied to the coupling shaft as a corresponding operational parameter, for example by means of a feeler lever of the type mentioned above. In the case of circuit breakers which, instead of a switching shaft, have an insulating crossbar connecting the switch contact arrangements, the position of the insulating crossbar can be used as a parameter.

The readiness for switching on the circuit breaker can also be indicated mechanically. This can can be achieved in that for signaling that the circuit breaker is ready to be switched on, a movement which is dependent on the state of the energy store and which is actuated by the clutch lever and by a movement can be fed to a mechanical AND gate which forms or actuates a display element in order to make the circuit breaker ready to switch on only to signal when the energy store is charged and the clutch shaft is not actuated. A signaling switch can be connected to this AND element or display element.

Instead of the separate AND element for indicating the readiness for switch-on, a parameter dependent on the state of charge of the energy store can also be supplied to the clutch shaft, the position of the clutch shaft or the clutch element controlled by it directly serving to indicate the readiness for switch-on.

The coupling element offers the possibility, in addition to the manual initiation of a switch-on command, to also process an ON command transmitted by remote control. This can be done in that the coupling member has an additional working surface, which is only effective in the coupled state, for initiating a parameter "state of a solenoid".

The invention is explained below with reference to the embodiment shown in the figures.

In Figure 1, parts of a circuit breaker are shown schematically, while operational parameters in the form of

Function blocks are indicated. The arrangement is in the "ready to start" state.

FIG. 2 shows the arrangement according to FIG. 1 in the “not ready to switch on” state due to closed switch contacts and an uncharged energy store. In FIG. 3, the device according to FIG. 1 is also in the “not ready to switch on” state due to the under-voltage release not being excited.

In Figure 1, essential components of a circuit breaker 1 are shown schematically together with a number of internal and external peripheral devices. In particular, a control panel 2 with a push button 3 for switching on and a push button 4 for switching off can be seen. The pushbutton 3 interacts with a latching device which comprises a switch-on half-shaft 5 rotatably mounted in bearings (not shown) and a switch-on pawl lever 6. The switch-on pawl lever 6 is arranged in the course of a mechanical power transmission which leads from an energy store 7 to a switching shaft 10 and from there to one or more switching contacts 11.

The pushbutton 4 controls a trip half-shaft 12, which is also rotatably mounted and on which a switch-off ratchet lever 13 is supported. The switch-on half-wave 5 and the release half-wave 12 are biased in their idle state by a tension spring 14 or 15 in their latching position.

The pushbutton 3 is connected by means of a switch-on plunger 16 to a lever carrier 17 which is movable about a fixed pivot bearing 18 and which has the function of an angle lever. On the lever bracket 17, a coupling member 20 is also articulated by a bearing 19, which is provided with a coupling pin 21 for a driving pin 22 acting on the switch-on half-shaft 5. By pivoting the lever-like coupling member 20 in a manner to be described below about its bearing 19 located on the lever support 17, the coupling pin 21 can be pivoted out of the position shown in FIG. The coupling member 20 permits rotation of the switch-on half-shaft 5 only in the position shown in FIG of Figure 1. If the coupling member 20 is pivoted in the direction of arrow 23 about its bearing 19, actuation of the push button 3 has no effect.

The actuation of the release half-shaft 12 by the pushbutton 4 takes place via a switch-off plunger 24, an angle lever-like rod support 25 with a pivot bearing 26 and a drive rod 28 connected to the rod support 25 by a swivel joint 27. The drive rod 28 engages with an elongated hole 29 or an equivalent one Arrangement via a driver 30 of the release half-wave 12. The shown rest position of the rod carrier 25 is maintained by a tension spring 31.

The coupling member 20 can be actuated by a coupling shaft 32 which is mounted below and between the switch-on half shaft 5 and the release half shaft 12 in a fixed bearing 33. The coupling shaft 32 is provided with a steering lever 34 which interacts with a boom 35 of the release half-shaft 12. A feeler lever 36 of the clutch shaft 32 is biased by a tension spring 37 into its rest position shown, in which the steering lever 34 abuts a fixed stop 40. A coupling rod 41 is also articulated on the boom 36 for connection to the lever 20. The coupling member 20 can thus be pivoted out of its coupling position shown in FIG. 1 by a counterclockwise rotation of the coupling shaft 32 in the direction of the arrow 23. By arranging the coupling rod 41 approximately at right angles to the coupling member 20, it is ensured that the coupling member 20 can be displaced by means of the pushbutton 3 and the lever support 17 without hindrance.

The clutch shaft 32 can be acted upon by a series of operational parameters, which are a mechanical movement in the direction of an arrow 42 shown in FIG. 1 Act. 1 shows operational parameters A, B, C, D and E which are explained below.

The parameter A signals the position of the switch shaft 10 and thus the position of the switch contacts 11. This feature is essential for the release or blocking of the switch-on, because release of the energy store 7 when the switch contacts 11 are closed leads to damage due to the lack of energy required by the switching mechanism can lead.

Parameter B means "overcurrent release missing" and signals that the trip block essential for the protective function of the circuit breaker 1 has not been connected in the intended manner to the circuit breaker 1 and consequently the circuit breaker 1 cannot perform its protective function.

Parameter C contains the message of the position of other circuit breakers against which the operation of circuit breaker 1 is to be locked. This dependency can exist for one or more further circuit breakers. FIG. 1 shows the interlocking against two further circuit breakers Q2 and Q3, the switching position of which can be fed to the coupling shaft 32.

The parameter D indicates the position of the switch cell door in which the circuit breaker 1 is located, which is important for the safety of the operating personnel. If the door is open, the clutch shaft 32 is also actuated.

If the circuit breaker is displaceably arranged on a slide-in unit, the position of the circuit breaker in the slide-in carrier is also important for the decision as to whether or not it can be switched on. It should not be possible in intermediate positions, ie outside the disconnected position, the test position and the operating position be to turn on the circuit breaker 1. In these cases too, a corresponding rotation of the clutch shaft 32 counterclockwise disengages the clutch lever 20 in the direction of arrow 23 from the switch-on half shaft 5.

The described parameters A and B belong to the circuit breaker 1 and are therefore "internal" parameters, while the parameters C, D and E are "external", i. H. Represent signals to be supplied from outside the circuit breaker 1. In a known manner, such signals can be supplied to the circuit breaker by linkage or cable pulls or similar means even after multiple deflections.

In addition to the parameters explained above, there are further parameters which represent an additional function per se for triggering the circuit breaker of devices. This applies in particular to an undervoltage release that is usually provided. If this is not energized because there is insufficient voltage, the circuit breaker cannot be closed. The parameter M1 shown in the figures "state of the undervoltage release" should then cause the display "not ready to be switched on". For this purpose, the undervoltage release acts in a suitable manner on the release half-shaft 12, the arm 35 of which actuates the clutch shaft by means of the steering lever 34 as well as one of the parameters A to E. In addition, the arm 35 can be actuated by further parameters, in particular by a parameter M2, which denotes the state of a tripping magnet which is controlled by an overcurrent release.

The position of the coupling member 20 basically signals that the circuit breaker 1 is ready to be switched on. This property is used to take into account a further parameter S "state of excitation of the solenoid". This is done by means of a work surface 43 at the upper end

Coupling member 20 pivoted in the direction of arrow 23 and the coupling pin 21 is out of engagement with the driver pin 22. Therefore, the left section 52 of the actuating bar 51 is in the lowered idle state. The right section 53 is also lowered because of

Energy storage 7 is relaxed. The display element 47 is now located below the viewing window 46.

FIG. 3 shows the state that the release half-wave 12 is actuated either by actuating the pushbutton 4 or by one of the parameters explained above, and as a result the clutch shaft 32 is rotated counterclockwise. The coupling member 20 is therefore pivoted to the right and the coupling pin 21 is out of engagement with the driver pin 22. This is the left

Transfer member 54 withdrawn the support by the working surface on the coupling member 20 and the left section 52 of the actuating bar 51 is lowered. In contrast, the right section 53 is raised because the energy store 7 is tensioned. The display element 47 thus only performs one rotation, but does not reach the area of the

Viewing window 46. i

Instead of the separate AND link described in the area of the display element 47, the readiness to switch on can be directly indicated by the position of the clutch shaft 32 or the clutch element 20 if the state of charge of the energy store 7 is supplied to the feeler lever 36 as a further parameter L. This is shown in FIG. 1 by a dash-dotted line of action 57.

As the figures show, the coupling pin 21 of the coupling member 20 has only one working surface for cooperation with the driving pin 22. An upper blocking surface 58 prevents the two pins from engaging in an undesired position and thereby the function of the device is disturbed.

Claims

claims 1. Device for controlling the switching on of a circuit breaker (1) depending on operational parameters (A ... E), whereby - The circuit breaker (1) relatively movable switch contacts (11) and for actuating the switch contacts (11) has an energy store (7) and a latching device (5, 6) through which the energy store can be latched in the charged state and by Can be released manually or remotely, - The operational parameters (A-E) and an "ON" command are each in the form of a mechanical movement, and - The switching contacts (11) through from the closed state Activation of a release latch (12, 13) can be converted into the open state, there is a common coupling shaft (32) for "OR" linking the operational parameters (A ... E, Ml, M2) and through the Coupling shaft (32) actuatable coupling member (20) for Transmission of an "ON" command to the latching device (5, 6). 2. Device according to claim 1, g e k e n n z e i c h n e t d u r c h the following features: - The latching device (5, 6) has a switch-on half-shaft (5) and a driver pin (22) connected to the switch-on half-shaft (5), - the coupling member (20) is movable about a pivot bearing (19) and is with a coupling pin (21) which grips the driver pin (22) is provided, - The pivot bearing (19) is located on a pivotally mounted and operable by an "ON" command lever bracket (17), wherein actuation of the lever bracket (17) a displacement of the pivot bearing (19) of the coupling member (20) in the sense of a rotation of the switch-on half-shaft (5) for releasing the energy store (17), and - the coupling member (20) can be pivoted about its pivot bearing (19) by the coupling shaft (32) around the coupling pin (21 ) engaged or disengaged from the driver pin To bring (22). 3. Device according to claim 1 or 2, d a d u r c h g e k e n n z e i c h n e t that the coupling shaft (22) at least one feeler lever (36) for Scanning of operating parameters (A ... E) occurring inside and outside the circuit breaker (1), these parameters being in particular A: "position of the switching contacts", B: "presence of an overcurrent release", C: "Switch position of at least one further circuit breaker", D: "Position of the door of a circuit breaker receiving the circuit breaker (1)" and E: "State of the travel drive of the circuit breaker in a rack". 4. Device according to claim 3, characterized in that one of the release latch (12, 13) belonging to the release half-shaft (12) has a boom (35) and that the coupling shaft (32) cooperates with the boom (35) in such a steering lever ( 36), that when the release half-shaft (12) is acted upon, the clutch shaft (32) is also rotated to actuate the clutch member (20) in order to disengage the clutch pin (21) from the driver pin (22). 5. Device according to claim 4, characterized in that at least one further operational parameter (Ml); in particular "State of excitation of an undervoltage release", the trip half-wave (12) can be fed. 6. Device according to claim 3, d a d u r c h g e k e n n z e i c h n e t that the position of a switching shaft (10) actuating the switching shaft (10) of the clutch shaft (32) can be fed to achieve an empty switching and pump prevention. 7. Device according to one of the preceding claims, characterized in that for reporting the readiness for switching on the circuit breaker (1) by the coupling member (20) and by a state of the energy store (7) dependent movement of a mechanical AND element can be fed, the a display element (47) carries or actuates in order to signal that the circuit breaker (1) is ready to be switched on only when the energy store (7) is tensioned and the clutch shaft (20) is not actuated. 8. Device according to one of the preceding claims, characterized in that a from the state of charge of the energy store (7) dependent parameter (L) can also be supplied to the clutch shaft (32) and that the position of the clutch shaft (32) or the clutch member controlled by it (20) is used directly to indicate the readiness to switch on. 9. Device according to one of the preceding claims, that the coupling member (20) has an additional working surface (43) effective only in the coupled state for initiating a parameter "state of a solenoid" (S).