DE102004061281A1 - Switching device increased isolation switching resistance has passive damping cylinder connected to pawl or at least one movable element for damping movement of pawl - Google Patents

Abstract

The switching device has a rotatable pawl (1), a stop (3) that limits the rotation region of the pawl, at least one movable element connected to the pawl and a passive damping cylinder (7) connected to the pawl or the at least one movable element for damping a movement of the pawl. The rotatable pawl is a release element with which the switching device can be unlatched into an OFF state. An independent claim is also included for a method of operating a switching device.

Description

The The present invention relates to a switching device, in particular a low voltage switch with a rotating latch, a Stop limiting the range of rotation of the latch, and at least a movable member connected to the pawl. Furthermore The present invention relates to a method for operating a Switching device by unlatching a rotatable pawl and stop a rotary movement of the latch with a stop.

Becomes a low voltage switch, for example, by a controller electronically switched on, so may during this power-on command quite a short circuit or an emergency stop request occur. In this case, the switch-on process must be canceled be and a corresponding latch, z. B. a notch, beats with high Energy against a stop. This switching process is called drive blanking or free release. In this case, the spring accumulator of the switching device is discharged, without that it is a contact may come. Before removing the circuit breaker from a slot it may be necessary, the tensioned spring accumulator of the circuit breaker to unload an empty circuit.

at the free trips or drive clear circuits for targeted unloading of the tensioned spring accumulator it comes to very high loads for the lock chain and the Latching elements of the drive unit of a circuit breaker. For example become the stops and the latches are damaged at the high impact speeds. These Carry loads in most cases to premature precipitate after the required service life of the switching device.

From the patent DE 101 20 783 C1 is such a switching mechanism for latching a spring accumulator known. In the relaxed position of the spring accumulator, the main pawl is supported on a stop pin. This stopper bolt must absorb the energy of the spring accumulator when unlatching.

In addition, from the patent DE 40 23 740 C2 a switching drive with an elastic bump stop known, to which a driving lever comes in an off position to the plant. In order to prevent an undesired re-bounce process when switching off, a reverse bounce is proposed. If the current to be disconnected reaches an order of magnitude that is critically critical, a sensor automatically detects this magnitude and applies a trigger to electrodes in such a way that the viscosity of a liquid in a lifting cylinder increases to such an extent that the movement of the member or the lifting cylinder in the liquid is correspondingly strongly attenuated. For a rebound is reliably prevented.

The Object of the present invention is the movement of a Latch with simple and inexpensive Means to attenuate when switching off.

According to the invention this Task solved by a switching device, in particular low-voltage circuit breaker, with a rotatable pawl, a stop that limits the range of rotation the pawl is limited, and at least one movable member, the connected to the pawl, wherein a passive damping cylinder with the pawl or the at least one member for damping a Movement of the pawl is connected.

Furthermore is provided according to the invention a method of operating a switching device by unlatching a rotatable pawl and terminating a rotary movement of the pawl with a stop as well as reducing the speed of the rotary motion the pawl by a passive damping cylinder before hitting it on the stop.

In advantageous way thus by a cost-effective damping cylinder reduce the speed of the latch when switching off, so that the corresponding components mechanically less loaded become.

Preferably the rotatable pawl is a notch with which the switching device is unlatched in an OFF state. This is especially the one Latch protected, which is usually damaged the most in a drive-off circuit.

Of the Stop the switching device may be a switching shaft. Thereby can be dispensed with a specially provided stop.

A particularly preferred embodiment of the present invention is that the passive damping cylinder is an air cylinder and in particular an open air cylinder. Through a specifically chosen orifice, air flows into or out of the cylinder through piston movement and provides adequate cushioning of the pawl. A corresponding pneumatic damping cylinder is easy to manufacture and practically maintenance-free. Alternatively, a closed cylinder may be used in which the air, a special gas or a liquid flows through recesses in the piston.

One Piston of the damping cylinder can directly to the rotatable pawl or the movable member be coupled. The immediate damping of the latch has the advantage that tolerance chains regarding the links of the switch lock can usually be disregarded. at a damping a member of the switching chain can the available installation space below Circumstances rather Be taken into account.

The The present invention will now be described in detail with reference to the accompanying drawings, in which: show:

1 a circuit breaker in the latched state with a relaxed spring accumulator, switch position "ON" of the circuit breaker;

2 the circuit breaker of 1 in OFF state, spring loaded;

3 the circuit breaker in the unlatched state, spring-loaded, switch-off position "off".

The below described embodiment represents a preferred embodiment of present invention.

The in 1 reproduced section of a circuit breaker shows a notch 1 , which can be unlatched to turn off the circuit breaker. In the in the 1 shown state is it with a half-wave 2 latched. After the operational unlatching would the Ausklinke 1 at the selector shaft 3 attacks.

The spring store 4 is in the in 1 illustrated state relaxed. The force on the Ausklinke comes from the Schaltpol, not shown.

The handle 1 is with a piston 6 a damping cylinder 7 connected. The damping cylinder 7 is filled with air and the piston 6 pushes the air through a defined opening 8th from the damping cylinder 7 or sucks the air through this opening 8th at. In the in 1 As shown, the air is almost completely out of the damping cylinder 7 crowded.

In 2 now the einschaltbereite state of the circuit breaker is shown, wherein the spring accumulator 4 is curious. The Ausklinke 1 is still in the latched state and is at the half-wave 2 at. This is also the position of the piston 6 in the damping cylinder 7 across from 1 unchanged.

Will now be appropriate 3 the notch 1 by turning the half-wave 2 unlatched, so moves the notch 1 driven by the spring accumulator 4 against the resistance of the return spring 9 on the shift shaft 3 to. Would be the damping cylinder 7 not available, would be the Ausklinke by the high storage energy 1 be accelerated very strong and with high energy in the stop, ie the shift shaft 3 , beat. This would severely damage the detective 1 , but also the shift shaft 3 to lead. For this reason, a damping of the stop is the notch 1 or the targeted braking of the detent 1 necessary. In principle, the effect of the acceleration forces could be reduced by intermediately mounted rubber stops. This reduces the effects of drive-by-circuit blows on component strength.

According to the invention but now proposed, the movement of the notch 1 even before hitting the stop or the selector shaft 3 to break. This is done by a speed-dependent damping with the damping cylinder 7 reached. When moving the notch 1 in the direction of the switching shaft 3 becomes the piston 6 from the damping cylinder 7 drawn. This is due to the defined opening 8th Air in the damping cylinder 7 sucked. The flow resistance of the air at the opening 8th ensures a speed reduction of the pawl 1 , so that their damage or damage to the stem 3 can be avoided in the drive empty circuit.

Alternatively to the vent hole or opening 8th in the damping cylinder 7 can also be between the piston 6 and the cylinder 7 a game can be provided. This defined play in turn allows the inflow and outflow of air into the cylinder.

1

pawl

2

half wave

3

Stop / shift shaft

4

spring

5

switching chain

6

piston

7

damping cylinder

8th

opening

9

Return spring

Claims (8)

Switching device, in particular Niederspan circuit breaker, with - a rotatable latch ( 1 ), - a stop ( 3 ), which determines the range of rotation of the pawl ( 1 ), and - at least one movable member connected to the pawl ( 1 ), characterized in that - a passive damping cylinder ( 7 ) with the pawl ( 1 ) or the at least one member for damping a movement of the pawl ( 1 ) connected is. Switching device according to claim 1, wherein the rotatable pawl ( 1 ) is a Ausklinke with which the switching device is unlatched in an OFF state. Switching device according to claim 1 or 2, wherein the stop ( 3 ) is a switching shaft. Switching device according to one of the preceding claims, wherein the passive damping cylinder ( 7 ) is an open air cylinder. Switching device according to one of the preceding claims, wherein a piston ( 6 ) of the damping cylinder ( 7 ) directly to the rotatable pawl ( 1 ) or the movable member is coupled. Method for operating a switching device by - unlatching a rotatable pawl ( 1 ) and - terminating a rotary movement of the pawl ( 1 ) with a stop ( 3 ), characterized by - reducing the speed of rotation of the pawl ( 1 ) by a passive damping cylinder before hitting the stop ( 3 ). The method of claim 6, wherein unlatching during a Switching the switching device takes place. A method according to claim 6 or 7, wherein reducing the speed by restricting an air flow in the damping cylinder (10). 7 ) he follows.