EP3293751A1 - Operating mechanism for a low voltage circuit breaker - Google Patents

Abstract

The invention relates to a switch lock for a low-voltage protection device with two opposing circuit boards (1, 2), wherein between the circuit boards (1, 2) a rotatable handle (3) is arranged, which is connected to a roller (16) via a bracket (15). is in active connection. The invention is characterized in that the roller (15) is in operative connection with a retrofittable device for pivotal switching, via which a shift lever (5) is to be moved to a corresponding shift position.

Description

The invention relates to a switching mechanism for a low-voltage protection device with two opposing circuit boards, wherein between the circuit boards, a rotatable handle is arranged, which is operatively connected via a bracket with a roller.

Low-voltage protection devices, in particular circuit breakers, serve, among other things, the safe shutdown in the event of a short circuit and thus protect consumer installations. Furthermore, electrical or mechanical switching units are suitable for the operational manual switching of consumers as well as for the safe disconnection of a system from the mains during maintenance work or when changing the system. Electrical switching units are often operated electromagnetically.

That is, such switching units are high-quality electrical switching devices with integrated protection for motors, lines, transformers and generators. They are used more closely at workstations with a lower switching frequency. Such switching units are suitable in addition to the short circuit protection for overload protection.

In the case of a short circuit, an electrical switching unit switches off an electrical system safely. Thus, this provides a protection against overload. Every conductor through which electricity flows heats up more or less. The heating depends on the ratio of the current to the conductor cross-section, the so-called current density. The current density must not be too large, otherwise the overheating can spatter the conductor insulation or possibly cause a fire. To protect electrical equipment against this damaging effect, switching units are used as overcurrent protection devices.

Circuit breakers have two separate release mechanisms for overload and short-circuit protection. Both triggers are connected in series. The short-circuit protection is provided by an electrical release that works almost instantaneously. In the event of a short circuit, the electromagnetic release unlocks without delay a circuit breaker of the circuit breaker. A switching armature disconnects the contactor before the short-circuit current can reach its maximum value.

Known switching units have a contact slide unit with a contact slide and a movable contact piece. The movable contact piece also has electrical contacts. Furthermore, such switching units have first contacts to a power line. In an on state, the electrical contacts of the movable contact piece contact the fixed contacts of the switching unit. In the event of a short circuit, the electrical contacts of the movable contact piece are released from the fixed contacts, so that the flow of current is interrupted. In this case, the movable contact piece is released from the contacts.

In addition to their protective functions as overload and short-circuit releases, as already mentioned above, circuit breakers also fulfill the normative switching on and off of motors. To prove these functions, the circuit-breakers must be able to switch on ten times the rated motor current according to the product standard. To ensure this limit load, it is necessary that the circuit breaker closes the double interruption of the three current paths in the form of a movable bridge with two movable contact points and two fixed contact points, almost simultaneously and in a jump function.

To realize this function is released via a hand-operated mechanism, in the form of an actuator, a switching mechanism and an actuating chain, the contact mechanism of contact slide and a movable bridge. The Release is done by a so-called quick turn-on. The three contact systems are released by a mechanism only after the switch lock has already been turned on. Now, the spring-loaded in the form of a contact load spring determines the kinematics of the contact system when switching.

After striking the bridges on the Festschaltstücken the contact slide accelerates until it is reflected at a stop. The reflection and the resulting kinetic energy of the contact slide reopen the contact system. This can lead to welds with a simultaneously increased current in this current path.

For circuit-breakers with low nominal currents, the function of quick turn-on is not necessary. However, it would be desirable for the manufacturing process, if the switching locks of these circuit breakers could be provided by simple structural measures with a quick turn on in the form of a retrofit process.

Accordingly, the object of the present invention is to provide a switch lock for a low-voltage protection device with a retrofittable device for sudden switching.

This object is achieved by a switching mechanism with the features of claim 1. Advantageous embodiments and developments, which can be used individually or in combination with each other, are the subject of the dependent claims.

According to the invention this object is achieved by a switching mechanism for a low-voltage protection device with two opposing circuit boards, wherein between the circuit boards, a rotatable handle is arranged, which is operatively connected via a bracket with a roller. The invention is characterized by the fact that the role is in operative connection with a retrofittable means for pivotal switching, via which a shift lever is to be moved to a corresponding switching position.

The essence of the invention is that only a single switching mechanism subassembly is required by the retrofittable device for sudden switching, which can be manufactured and tested completely automated. The inventive retrofittable device for sudden switching has a locking part and a return spring, which can be retrofitted to adapt the switch lock for larger rated currents. In this case, first the locking part in the bearing pin, on which also the shift lever is arranged, snapped. Subsequently, the return spring is snapped with the locking part.

The return spring is designed so that it can be easily and safely mounted. The blocking part is still within the keyhole geometry and requires no additional space inside the complete unit.

This subsequent assembly of the locking part reduces the variance of the preassembled switch lock assembly. It can be used again on a preassembled standard switch lock, which is then configured depending on the use of differently strong, external tension springs and a retrofittable locking part.

This reduces the storage and handling costs. The need for quick-release switching locks can be controlled as needed and without much effort. The hitherto complicated manual assembly of the preassembled switch lock assembly is eliminated and is replaced by the simpler subsequent assembly of the finished assembly.

A continuation of the inventive concept can provide that the means for sudden switching has a blocking part.

A special embodiment of the inventive concept may consist in that the locking part can be snapped onto a bearing, on which also the shift lever is positioned.

An advantageous embodiment of the inventive concept may consist in that the locking part is Z-shaped with two mutually parallel tongues and a tongue region connecting the central region.

A continuation of this concept according to the invention may consist in that at the connecting central region a semi-concentric extension is formed, over which the locking part snaps onto the bearing, so that the shift lever and the locking part are mounted in the same bearing point.

A continuation of the inventive concept can provide that the tongue of the locking member is in operative connection with the roller.

A special embodiment of this concept according to the invention can provide that the means for sudden switching has a return spring.

An advantageous embodiment of the inventive concept may consist in that the restoring spring has J-shaped sections, which are connected to one another via a connection region.

A continuation of the inventive concept may provide that the J-shaped portions of the return spring are secured to the tongue of the locking member and to the circuit board.

The switching mechanism according to the invention for a low-voltage protection device has two opposing circuit boards, wherein between the circuit boards, a rotatable handle is arranged, which is operatively connected via a bracket with a roller. The role is in operative connection with a retrofittable means for pivotal switching, via which a shift lever is to be moved to a corresponding switching position. The device for sudden switching has a blocking part and a return spring. The blocking part is Z-shaped with two mutually parallel tongues and a tongue connecting the central region. At the connecting central region of the locking part a semi-concentric extension is formed over which the locking member snaps onto a bearing, wherein the shift lever and the locking member are mounted in the same bearing point. The tongue of the locking member is operatively connected to the roller. The assembly provides that first the locking part is snapped onto the bearing and then snapped the return spring with the locking part.

Further embodiments and advantages of the invention will be explained below with reference to embodiments and with reference to the drawing.

• Fig. 1 in einer perspektivischen Darstellung ein aus dem Stand der Technik bekanntes Schaltschloss ohne Schnelleinschaltfunktion;
• Fig. 2 in einer perspektivischen Darstellung ein erfindungsgemäßes Schaltschloss mit einer nachrüstbaren, separaten Einrichtung zum sprunghaften Einschalten in Form eines Sperrteils und einer Rückstellfeder;
• Fig. 3 in einer perspektivischen Darstellung das erfindungsgemäße Schaltschloss nach Fig. 2 mit montierter, nachrüstbarer Einrichtung zum sprunghaften Einschalten;
• Fig. 4 in einer Draufsicht das erfindungsgemäße Schaltschloss mit der Übertragungsmechanik aus Bügel und Rolle im ausgeschalteten Schaltstellungszustand;
• Fig. 5 in einer Draufsicht das erfindungsgemäße Schaltschloss mit der Übertragungsmechanik aus Bügel und Rolle am Beginn der Auslenkung des Sperrteils;
• Fig. 6 in einer Draufsicht das erfindungsgemäße Schaltschloss mit der Übertragungsmechanik aus Bügel und Rolle im eingeschalteten Schaltstellungszustand.

Here are shown schematically:

• Fig. 1 in a perspective view of a known from the prior art switch lock without fast turn-on;
• Fig. 2 in a perspective view of an inventive switching mechanism with a retrofittable, separate means for sudden switching in the form of a locking member and a return spring;
• Fig. 3 in a perspective view of the switching mechanism according to the invention Fig. 2 with mounted, retrofittable device for sudden switching on;
• Fig. 4 in a plan view of the switching mechanism according to the invention with the transmission mechanism of bracket and roller in the off switching position state;
• Fig. 5 in a plan view of the switching mechanism according to the invention with the transmission mechanism of bracket and roller at the beginning of the deflection of the locking member;
• Fig. 6 in a plan view of the switching mechanism according to the invention with the transmission mechanism of bracket and roller in the switched position switching state.

In Fig. 1 is shown a switching lock from the prior art. The switching mechanism has two opposing circuit boards 1, 2, wherein between the circuit boards 1, 2, a rotatably mounted handle 3 is arranged. The handle 3 is connected via a transmission mechanism with a arranged on a bearing 4 shift lever 5 in operative connection. The Fig. 1 shows a switch lock without quick turn-on.

In Fig. 2 an inventive switch lock is shown with a separately shown retrofittable device for sudden switching in the form of a locking member 6 and a return spring 7. The switch lock according to the invention also has two opposing circuit boards 1, 2, wherein between the circuit boards 1, 2 arranged a rotatable handle 3 is that is connected via a transmission mechanism with a bearing 4 arranged on the shift lever 5 in operative connection. The locking member 6 is Z-shaped with two mutually parallel tongues 8, 9 and the tongues 8, 9 connecting central region 10. At the connecting central region 10, a semi-concentric extension 11 is integrally formed, over which the locking member 6 snaps onto the bearing 4 , so that the shift lever 5 and the locking member 6 are mounted in the same bearing point.

The return spring 7 has two J-shaped sections 12, 13, which are connected to each other via a connecting portion 14.

In Fig. 3 the switching mechanism according to the invention is shown with mounted, retrofittable device for sudden switching. Out Fig. 3 shows that on the tongue 9 of the locking member 6, a J-shaped portion 12 of the return spring 7 is attached. The other J-shaped portion 13 of the return spring 7 is attached to the circuit board 2 of the switching mechanism.

In Fig. 4 the switching mechanism according to the invention with the transmission mechanism of bracket 15 and roller 16 is shown in the off switching position state. When switched off switching position, the roller 16 is spaced from the tongue 8 of the locking member 6. From the Fig. 4 also shows that the semi-concentric extension 11 are mounted on the locking part 6 together with the shift lever 5 in a bearing 4.

In Fig. 5 shows the switching mechanism according to the invention with the transmission mechanism of bracket 15 and roller 16 at the beginning of the deflection of the locking member 6. The roller 16 moves through the deflection on the tongue 8 of the locking member 6 until the roller 16 and the tongue 8 of the locking member 6 a have common touch point. In the further course of the deflection then also moves the shift lever 5, which is positioned with the locking part 6 on the bearing 4.

Fig. 6 the switching mechanism according to the invention with the transmission mechanism of bracket 15 and roller 16 is shown in the switched position switching state.

The switching mechanism according to the invention for low-voltage protection devices with a retrofittable device for sudden switching is characterized in that by the subsequent Assembly of the locking member or the return spring, the variance of the preassembled switch lock assembly is reduced. It can be used again on a pre-assembled standard switch lock, which is then configured depending on the use of the differently strong tension springs and a retrofit locking part. This reduces the storage and handling effort. The need for quick-release switching locks can be controlled as needed and without much effort. The hitherto complicated manual assembly of the preassembled switch lock assembly is eliminated and is replaced by the simple subsequent assembly of the finished assembly. It should be added that the locking part is still within the keyhole geometry and requires no additional space inside the complete unit.

LIST OF REFERENCE NUMBERS

1

circuit board

2

circuit board

3

handle

4

camp

5

gear lever

6

blocking part

7

Return spring

8th

tongue

9

tongue

10

the central region

11

semi-concentric extension

12

J-shaped section

13

J-shaped section

14

connecting area

15

hanger

16

role

Claims (9)

Switch lock for a low-voltage protection device with two circuit boards (1, 2) lying opposite one another, wherein a rotatable handle (3) is arranged between the circuit boards (1, 2) and is operatively connected to a roller (16) via a bracket (15), characterized in that the roller (16) is in operative connection with a retrofittable means for pivotal switching, via which a shift lever (5) is to be moved to a corresponding switching position. Switch lock according to claim 1, characterized in that the device for sudden switching has a blocking part (6). Switch lock according to Claim 2, characterized in that the locking part (6) can be snapped onto a bearing (4) on which the shift lever (5) is also positioned. Switch lock according to claim 2 or 3, characterized in that the locking part (6) is Z-shaped with two mutually parallel tongues (8,9) and the tongues (8,9) connecting central region (10). Switch lock according to claim 4, characterized in that at the connecting central region (10) a semi-concentric extension (11) is integrally formed, over which the locking part (6) on the bearing (4) snaps, so that the shift lever (5) and the locking part ( 6) are stored in the same bearing point. Switch lock according to Claim 4, characterized in that the tongue (8) of the blocking part (6) is in operative connection with the roller (16). Switch lock according to one of claims 1 to 6, characterized in that the device for sudden switching has a return spring (7). Switch lock according to claim 7, characterized in that the restoring spring (7) has two J-shaped sections (12, 13) which are connected to one another via a connection region (14). Switch lock according to claim 8, characterized in that the J-shaped portions (12,13) of the return spring (7) on the tongue (9) of the locking part (6) and on the circuit board (2) are attached.

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