EA001449B1 - Device for indicating an electrical fault in a breaking device such as a differential switch - Google Patents

Abstract

1. A device for indicating an electrical fault in a breaking device such as a differential switch comprising: - a pair of separable contacts per pole, in electrical connection with a pair of connection terminals, - a contact operating mechanism, comprising a handle connected by a mechanical transmission link to a drive part of the contacts, - a trip device comprising a means for detecting an electrical fault and a tripping means such as an electromagnet able to bring about opening of the contacts when automatic tripping occurs following a fault, and - a means for indicating the tripped state of the switchgear apparatus, comprising an indicator able to occupy either a first inactive stable position or a second active stable position indicating the fault due to the action of the electromagnet, characterized in that it comprises a means (3), driven by the handle (2), for holding the indicator in the above-mentioned second position against the action of a means (10, 12) for returning said indicator (5) to the first position, so as to store the tripping information until a closing operation of the apparatus is performed. 2. The device according to claim 1, characterized in that the indicator (5) is driven positively by the electromagnet (11) between the two above-mentioned positions. 3. The device according to claim 1 or 2, characterized in that the above-mentioned tripping means (11) is an electromagnet with a plunger core (8) and the indicator (5) is driven positively by the plunger core (8) between the two above-mentioned positions. 4. The device according to any one of the foregoing claims, characterized in that the indicator (5) is mounted rotating around a fixed axis (9) of the apparatus, is connected in articulated manner via one of its ends to the core (8) of the electromagnet (11), and cooperates via its other end with the means (3) for holding the indicator (5). 5. The device according to any one of the claims 1 to 3, characterized in that the indicator (5) is articulated around a fixed axis (9) of the apparatus, and comprises a first end (5a) cooperating with the means for holding (3) and a second end (5b) connected to the core (8) of the electromagnet (11), in such a way that the indicator (5) is driven by the core (8) in the tripping direction and moves in rotation with respect to said core when resetting of the latter takes place. 6. The device according to claim 5, characterized in that the indicator (5) comprises in addition a spring (12) able to return the indicator (5) to the rest position after the apparatus has been reset. 7. The device according to any one of the claims 3 to 6, characterized in that the indicating means M comprises a spring (6) fitted between the slide rack (3) and the case and able to return the slide rack (3) to the rest position when resetting of the apparatus takes place. 8. The device according to any one of the claims 3 to 7, characterized in that the handle (2) comprises a spigot (4) designed to operate in conjunction with the slide rack (3) so as it drive it after a certain travel when automatic tripping takes place, and not to drive it during a closing operation. 9. The device according to any one of the claims 4 to 8, characterized in that the indicator (5) comprises a spigot (14) operating in conjunction with a material clearance (15) arranged in the slide rack (3). 10. The device according to any one of the claims 4 to 10, characterized in that the indicator (5), on the side where the slide rack (3) is situated, comprises a flag (16) designed to cooperate with a window (13) provided in the case. 11. A switchgear apparatus equipped with a device according to any one of the foregoing claims. 12. The apparatus according to claim 11, characterized in that it has an auxiliary source. 13. A differential circuit breaker according to claim 12 or 13 characterized in that the device is used to detect an insulation fault.

Description

The present invention relates to an electrical fault indication device in a switching device, in particular, in a differential switch, comprising:

- a pair of individual contacts per pole, with an electrical connection using a pair of connecting terminals (terminals),

- contact actuator,

a shutdown device comprising means for detecting an electrical fault and means of shutdown, such as an electromagnet, configured to open contacts in the event that an automatic shutdown occurs following the occurrence of a fault, and

- means for indicating the switched off state of the switching device, comprising an indicator that can occupy the first inactive stable position or the second active stable position, indicating a fault, due to the action of the electromagnet.

Known differential switches or switches that contain means for indicating a differential fault, allowing the user to detect the insulation damage in his electrical installation.

Some of the known means of indication are used in the form of indicator lamps (systems of light-emitting diodes or other light indicators), depending on the state of the power source of the electrical installation that the switch protects. This results in the fact that it is almost impossible to provide the user with maximum security, especially given the fact that the information on the differential fault is not reliable regardless of the state of the source.

Other of these means are mechanical, for example, as described in document EP 0275750. This document describes a differential switch comprising a transformer and a relay, which interact by means of a shut-off plate with a latch with a lock and by means of a lock in the fault indication lever. The relay used is a relay with two stable positions with a magnetic snap type. However, this type of relay is relatively expensive, and in this embodiment the switch has a large number of parts.

Also known is document I8 4382270, which describes another means of mechanical indication of a solenoid type, but which must be individually returned to its original position.

The object of the present invention is to propose a malfunction indication device for a switching device, in particular, for a differential switch having a simple design and operating independently of the power source and which automatically returns to its original position, as well as an electric circuit switch made with this device .

A device of this type contains means for holding the indicator in the second position and means for returning the indicator to the first position in order to preserve the shutdown information until the device closes the operation.

According to an embodiment of the invention, the indicator is driven by force, by means of an electromagnet, between the two aforementioned positions.

According to a particular feature, the aforementioned means for automatic switching off is an electromagnet with a suction core and an indicator which is forcedly forced by the suction core between the two above-mentioned positions.

According to another aspect, the contact actuator comprises a knob connected by means of a mechanical transmission link with a part of the contact drive, and means for holding the indicator in a second position, which is actuated by means of said knob.

The present invention is also in the implementation of the switching device and, in particular, a differential switch or switch equipped with a device containing the previous features used individually or in combination.

Brief Description of the Drawings

The invention is illustrated by reference to the accompanying drawings, in which:

FIG. 1 and 2 show longitudinal local sections of a differential switch according to the invention, showing a specific embodiment of the display device, respectively, in the initial position and in the fault indication position;

FIG. 3 and 4 depict partial general views of the device corresponding to FIGS. 1 and 2;

FIG. 5, 6, 7 and 8 depict in perspective, respectively, the drive sleeve of the slide, the indicator, the slide and the return spring of the slide;

FIG. 9 and 10 depict views similar to FIG. 1 and 2, showing another embodiment of the display device;

FIG. 11 is a partial perspective view showing this other embodiment of the device in the display position;

FIG. 11a depicts a view similar to the previous view, but showing the device in the initial position;

FIG. 12, 13, 14 and 15 depict in perspective, respectively, a sleeve with a slider, an indicator, a slider and a spring with a slider, which are used in this second embodiment; and FIG. 16 is a perspective view showing the inside of a device equipped with a device according to a second embodiment of the invention.

Description of the preferred option implementation

The drawings depict a differential switch Ό, which is placed in the casing 1, which has the shape of a parallelepiped, made of extruded insulating material and made with the possibility of further installation using a clip on the rail (not shown). This switch Ό is made with the possibility of further connection to the AC power supply system through the connecting terminals provided in the casing 1, and can perform several functions. It can be a mechanism for automatically shutting down, and thus disconnecting the electrical circuit when overloaded, short-circuited in the circuit, or in the event that differential malfunctions occur.

This switch Ό contains means M for indicating a differential fault, which allows the user to diagnose the condition of an electrical installation, which may have insulation damage and a fault associated with no-load operation (idle), or a fault associated with a short circuit in the circuit. Through this indication means, the user, directly in working condition, can determine the damage to the insulation, as a result of which it is possible to effectively ensure the safety of people and property. For simplicity, only the differential part will be described below.

The known device, in its two embodiments, comprises a pair of separate contacts (not shown) on the pole, an actuator for operating two contacts, comprising a knob 2 connected with a mechanical transmission link to a part of the contact drive, a driving spring (not shown) for driving a mechanism that performs contact opening when an automatic shutdown occurs as a result of a malfunction, a differential shutdown device having a transformer to detect eye leaks, and an electromagnet 11 adapted to cooperate with a closing bolt of the mechanical link mechanism. This electromagnet 11 contains exhaust core 8, made with the possibility of sliding in the guide tube, formed with the help of the coil shell in the case when the current flows through the latter, between the initial position (rest position) (Fig. 1, 3 and 9, 11a) and the position active shutdown (Fig. 2, 4, 10 and 11). This core 8 automatically returns to its original position by means of a spring of 10 after automatic shutdown.

According to an embodiment (Fig. 18), the indication means M comprises a rod-shaped indicator 5, which is pivotally connected on the fixed axis 9 of the device, and the rod 5 is connected by the hinge method at one of its ends to the core 8 of the electromagnet 11 and contains at the opposite end a flag 1 6 for collaboration with a window 13 located on the upper part of the casing 1. Indicator 5 also includes a sleeve 1 4, which can work in conjunction with the protruding part 15 of the slide 3, which is installed with the possibility of sliding movement inside the casing 1 parallel to the direction of movement of the core 8. This slide 3 is driven with sliding using the handle 2 between the rest position ( Fig. 1) and the active position (Fig. 2), which will be described below. For this purpose, the handle 2 contains the sleeve 4, which allows the slide 3 to be set in motion after a certain closing movement of the handle 2. The spring 6 is installed between the slide 3 and the casing 1 to return the slide 3 to its original position.

According to an embodiment (Fig. 91 5), the indication means M comprises the same elements as previously described, and the indicator 5, which is connected in a hinged manner on a fixed axis 9 and has a first end 5a, cooperating with the fixation means 3, and a second end 5b connected to the core 8 of the electromagnet 11 so that the indicator 5 is set in motion with the help of the core 8 in the direction of switching off and rotates with respect to the core in the event that the core returns to its original position.

According to this embodiment, the indication means M further comprises a spring 1 2, which allows the flag 1 6 to return to its original position after the contact closing operation.

Below will be sequentially described the operation of the device according to the invention for two embodiments.

According to the first embodiment, when the switch Ό is in the closed position (Fig. 1 and 3), the switch and differential mechanisms are locked, and the flag 1 6 becomes invisible, that is, invisible through the window 13, because it is kept in position with the help of part 7 which itself is held by the core 8 of the differential shutdown system. In the case when a differential fault occurs (Fig. 2), and due to the shutdown force, which is set by means of the core 8 (arrow A), the indicator 5 and the flag 16 are rotated around the axis 9. The handle 2, free from latching on the switch side and equipped the connecting part 4, acts on the mechanism that drives the slide 3, which, due to the protrusion 1 5, when moving from left to right (arrow B) locks the sleeve 1 4 indicator flags and thus provides it with a visible position (Fig. 2 and 4) .

When the device returns to its original position, the spring 10 of the electromagnet 11 pushes the core 8 to the rear position and thus returns the differential assembly to the working position. The return spring 6 pushes the slider 3 to the rear position and thus unlocks the flag 16. Then the device is in the working position and is ready to perform its functions.

According to the second embodiment, in the case when the switch is closed (Fig. 9), the switch and the differential mechanisms are blocked and the flag 1 6 becomes invisible. In the case when a differential fault occurs (Figs. 10 and 11), and due to the action of the force of switching off by means of the core 8 (arrow A), the indicator 5 and, consequently, the flag 1 6 are rotated around the axis 9. The handle 2 released from the snap side of the switch and equipped with a connecting part or a sleeve 4, sets in motion a slide 3, which, moving from left to right (arrow B), blocks the sleeve 14 of the indicator flag 1 6, and thus places it in a visible position. Unlike the first embodiment, the core 8 then returns to its original position immediately after the switch is opened (an invisible position that becomes possible due to the fact that the indicator 5 can move with rotation relative to the core 8 in this direction). When the device returns to its original position (or closure), the return spring 6 pushes the slider 3 to the rear position and releases the indicator flag 1 6.

Spring 1 2 then returns flag 1 6 to its masked position. The device is then in a working position and is able to perform its functions. It should be noted that the window 1 3 has the additional function of protecting the internal mechanisms from the penetration of foreign bodies outside.

Technical advantages from the user's point of view are as follows.

The indicator flag works independently of the power source of the electrical installation that the switch protects, that is, it is mechanical. As a result, user safety is enhanced. Indeed, the separation of the circuits from the network side and the load side is guaranteed in all cases, the information on the differential fault is reliable regardless of the state of the source; the user is guaranteed reliability of isolation, and information about all faults is stored in memory.

The display becomes invisible using a simple operation of closing the switch by the user (some devices require action in two stages).

The technical advantages of the invention are as follows.

The voltage that is applied to the relays with differential shutdown is low, and therefore the reliability of the protection is not reduced. The force for driving the display means becomes practically low, and the friction that occurs during operation is reduced.

The resetting of the reset functions and the switch differential does not depend on the indication of the reset state. The functional mechanical connections between the differential function, the switch-off device and the differential failure indication function are in fact achieved in such a way that their initial state settings are independent.

The presence of a window made of a transparent material helps protect the device from external factors. The window protects the device from penetration of dust and other pollutants and eliminates any external influence on the operation of the indicator flag and, consequently, on the off relay.

It should be noted that the assembly mechanism becomes simple with the help of appropriate devices. One device allows the indicator flag to be kept in a stable position during assembly, while the second allows the automatic assembly of this spring in a functional position when the cover is installed. Another device allows you to fix the spring of the slide during its installation in the device.

Finally, it should be noted that, according to two embodiments, the display means has the ability to automatically return to its original position, due to the electromagnet spring in the case of the first embodiment, or due to the spring associated with the indicator, in the second embodiment.

Of course, the invention is not limited to the embodiments described and shown, which are given here by way of example only.

Thus, the invention can be applied in any switching device of systems supplied with electrical energy, or in others that require means of indicating an electrical fault.

In addition, although the device of the invention is particularly suitable for the case where an electromagnet is used with an exhaust type of core and therefore with a temporary action, it would also be possible to apply the concept outlined in paragraphs 1 and 2 to a switching device using a relay with a magnetic latch type.

The invention provides all technical equivalents of the described means and their combinations, if the latter are made in the scope of the invention.

Claims (13)

CLAIM 1. The device display an electrical fault in the switching device, in particular, in the differential switch, containing - a pair of individual contacts per pole in the case of switching using a pair of terminals, - a contact actuator in which a handle is provided that is connected by means of a mechanical transmission link to the driving part of the contacts, a shutdown device, in which means for detecting an electrical fault and shut-off means are provided, capable of opening the contacts in the event that an automatic shutdown occurs after the occurrence of the fault, and - means for indicating the off state, in which an indicator is provided which, due to the action of the electromagnet, occupies the first inactive stable position or the second active stable position, indicating a malfunction, characterized in that it contains means (3) driven by a handle ( 2) and serving to hold the indicator in the aforementioned second position for storing the shutdown information until the closure operation is performed, as well as means (10) for returning the indicator (5) the first position. 2. The device according to claim 1, characterized in that the aforementioned electromagnet (11) is an electromagnet with an exhaust core (8) for driving the indicator (5) between the two aforementioned positions. 3. Device according to any one of claims 1 to 2, characterized in that the means for holding the indicator (5) contains a slider (3), which is connected to the handle (2) to bring it into action when the handle (2) is moved between the position on and off position, in which the indicator (5) is held in the second position. 4. Device according to any one of paragraphs. 1-3, characterized in that the indicator (5) is installed with the possibility of rotation around the fixed axis (9) of the device, connected pivotally at one of its ends to the core (8) of the electromagnet (11) and mechanically connected with its other end to the means (3 ) to hold the indicator (5). 5. Device according to any one of paragraphs. 1-3, characterized in that the indicator (5) is hinged relative to the fixed axis (9) of the device, while its first end (5a) is in contact with the means for holding (3), and the second end (5b) is connected to the core (8) electromagnet (11) with the ability to bring the indicator (5) with the help of the core (8) in the direction of switching off and moving with rotation relative to the core when the latter returns to its original position. 6. The device according to claim 5, characterized in that the indicator (5) further comprises a spring (12), which allows the indicator (5) to return to the off position after returning the device to the off position. 7. Device according to any one of Claims 3-6, characterized in that a spring (6) is provided, mounted between the slider (3) and the casing (1) and allowing the slider (3) to return to the off position when the device is in the off position. 8. Device according to any one of paragraphs.3-7, characterized in that the handle (2) contains a sleeve (4), designed to interact with the slide (3), so that it sets it in motion after moving, when automatic shutdown occurs, and did not drive it during the closure operation. 9. Device according to any one of claims 4 to 8, characterized in that the indicator (5) contains a sleeve (14) that cooperates with a protrusion (15) located on the slider (3). 10. Device according to any one of claims 3 to 9, characterized in that the indicator (5) on the side where the slider is located (3) contains a flag (16) adapted to interact with the window (13) provided in the casing ( one). 11. A switching device equipped with a device according to any one of claims 1 to 10. 12. The device according to claim 11, characterized in that it has an auxiliary power source. 13. The device according to claim 11 or 12, in particular a differential switch, characterized in that it is adapted to detect insulation failure.