TECHNICAL FIELD

This specification relates to an operating mechanism for an electrical device, particularly a circuit breaker.

BACKGROUND

The German patent DE102011002862B4 discloses a device, for example a circuit breaker, with a rotatable handle having at least two handle positions. The device comprises a number of different color light sources corresponding to the number of handle positions. Within the handle between a first side of the handle and a second side of the handle, a photoconductive channel is formed, wherein the light sources are arranged relative to the first side of the handle, that per handle position, the light of only one light source is coupled into the photoconductive channel, so in that the grip position is optically indicated by the color of the respective light source on the second side of the handle, the light sources being formed as SMD LEDs on a printed circuit board, the printed circuit board being sandwiched between the rotatable handle and a handle panel, the light sources for the handle positions are selected according to the mechanical position of the rotatable handle.

The US patent US6903289B2 relates to a circuit breaker, which includes a housing having an opening, separable contacts within the housing, and an operating mechanism for opening and closing the separable contacts. The operating mechanism includes a generally transparent operating handle having a portion protruding through the opening of the housing. An auxiliary switch associated with the operating mechanism provides a first normally closed output when the separable contacts are open and a second normally open output when the separable contacts are closed. A first LED indicator cooperates with the first output, is proximate the operating handle and is illuminated when the separable contacts are open. A second LED indicator cooperates with the second output, is proximate the operating handle and is illuminated when the separable contacts are closed. One of the first and second LED indicators illuminates the operating handle. The German patent DE102015203510B3 relates to an overvoltage protection device having at least one overvoltage protection means, a first indicating means for actively optically signaling a state of the overvoltage protection device connected to an operating network, and a second indicating means for actively optically signaling a non- operational state of the overvoltage protection means. The overvoltage protection device, the first indicating means and the second indicating means are arranged spatially spaced apart from one another in a housing, with light from the first indicating means and the second indicating means being irradiated at different points of a light guide (optical waveguide) and being directed by means of the light guide to a common status display on a surface of the housing which is visible from the outside, with a color change being produced by superimposition of light from the first indicating means and the second indicating means when the overvoltage protection device is in a non- operational state and is connected to the operating network.

The German patent application DE102011082258A1 relates to a protective switching device having a status indicating device. The status indicating device comprises a light guide and two diodes, each of which is designed to couple light of a different color into the same light guide. The two diodes can be controlled independently of each other by a control device of the protective switching device and thus also simultaneously with each other.

The German patent application DE 102007014264A1 relates to a switching lever of a circuit breaker which can be set to the switching positions ON, OFF and TRIP and has a light emission unit connected to a voltage source, the light emission unit being designed in such a way that in operation it emits a light of different wavelength in each case to indicate the switching state of the switch, depending on the ON, OFF or TRIP switching lever position. The light emission unit is arranged in the switch lever in such a way that the light emitted by it emerges from the switch lever and, on the basis of a specific color, provides an operator of the switchgear with information about the switching state. In the closed switching state of the switch (ON), a red light (approx. 650-750 nm wavelength) is emitted, in the TRIP switching state, a yellow light (approx. 547 nm wavelength) is emitted, and in the OFF switching state, a green light (approx. 490-575 nm wavelength) is emitted from the switching lever. This means that a specific color is assigned to each switching state or each of the three switching lever positions ON, OFF and TRIP.

The US patent US4,969,063 is related to an electrical circuit breaker operable between three status conditions and having means for displaying the status condition of the breaker. Auxiliary switching means are incorporated into a breaker system to be automatically operable to a plurality of different switching conditions indicative of the status of the breaker. Associated control circuitry powered from incoming power lines and not connected to the breaker load terminal are governed by the status of the auxiliary switching system to energize a luminous display element to three different output conditions each condition indicative of a different switching condition of the breaker. In the preferred form of the invention the output takes the form of a tri-state indicator consisting of a red and a green light emitting diode, selective excitation of the individual diodes by the controlled circuitry producing a red or green light output, and simultaneous excitation of the two diodes providing a perceived orange display color.

SUMMARY

This specification describes embodiments of an operating mechanism for an electrical device, particularly a circuit breaker. A generally transparent operating handle and at least two light sources for generating light with different colors are provided. Generally transparent means that light emitted into the operating handle can illuminate the handle to be visible for a human. The operating handle has a light entry section with at least one light blocking mask. The at least two light sources are arranged such that their emitted light can be coupled into the operating handle through the light entry section. The light entry section with the mask is movable with the operating handle in relation to the at least two light sources so that in different positions of the operating handle the at least one mask blocks light from at least one light source from entering the light entry section. Thus, a technical less complex solution for indicating a status of an electrical device can be implemented. Particularly, no complex electronic control of a status indication of an electrical device is required. Moreover, the provided solution does not require any sensors for determining a status of the electrical device comprising the operating handle. Yet further, by mixing the different light colors from the at least two light sources in the operating handle, a third or more colors can be provided for indicating a further status of the electrical device, which does not require a dedicated light source. Also, no signal conversion circuitry for converting a determined status of the electrical device into an electrical signal for illuminating the operating handle is required. Generally, the proposed solution avoids complex electronics for status indication in an electrical device, which is in some implementations not desired and/or increases the risk of failure.

According to an aspect of this specification, an operating mechanism for an electrical device, particularly a circuit breaker, is provided, wherein the operating mechanism comprises a generally transparent operating handle comprising a light entry section with at least one light blocking mask, and at least two light sources for generating light with different colors and being arranged such that their emitted light is coupled into the operating handle through the light entry section, wherein the light entry section with the mask is movable with the operating handle in relation to the at least two light sources so that in at least one position of the operating handle the at least one mask blocks light from at least one light source from entering the light entry section.

In an embodiment, the light entry section may be formed by a bearing of the operating handle. The bearing can be for example a bearing for turning the operating handle around an axis.

In embodiments, the light blocking mask may be formed as a part separate from the light entry section. In alternative embodiments, the light blocking mask can be formed as a zone of the light entry section, particularly as an opaque ink or coating or any other physical mask on the light entry section stopping light from entering the light entry section.

In further embodiments, the at least two light sources may be permanently powered throughout the usage of the electrical device comprising the operating mechanism. Thus, no complex electronics for controlling the light sources is required, only a power supply to permanently power them.

In yet further embodiments, two light sources for generating light with two different colors may be provided, and the light entry section may comprise one light blocking mask and may be movable with the operating handle between three different positions in relation to the two light sources so that in a first one of the three positions of the operating handle the mask blocks light from the first light source, in a second one of the three positions of the operating handle the mask blocks light from the second light source, and in the third position of the operating handle the mask does essentially not block light from both light sources.

In an embodiment, the electrical device may be a circuit breaker operable between three or more status conditions, wherein each status condition is associated with a different one of the three or more positions of the operating handle. In a further embodiment, a first status condition may be ‘circuit closed’ being associated with a first position, a second status condition may be ‘tripped’ being associated with a third position, and a third status condition may be ‘opened’ being associated with a second position. In a yet further embodiment, the first light source may generate light with a red color and the second light source may generate light with a green color.

According to a further aspect of this specification, a circuit breaker is provided, which comprises an operating mechanism as disclosed herein.

The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features and advantages will be apparent from the description and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

Fig. 1 shows the general concept of an operating mechanism for a circuit breaker according to an embodiment with two light sources and three different positions of an operating handle of the circuit breaker; and

Fig. 2 shows the general concept of an operating mechanism for a circuit breaker according to an embodiment with three light sources and three different positions of an operating handle of the circuit breaker. DETAILED DESCRIPTION

In the following, functionally similar or identical elements may have the same reference numerals. Absolute values are shown below by way of example only and should not be construed as limiting.

Fig. 1 shows an operating mechanism 10 for a circuit breaker (not shown) comprising an operating handle 12, which is generally transparent for light of the human visible frequency spectrum, for example made from a transparent material such as a kind of transparent plastics material. The operating handle 12 comprises a light entry section 14, which is formed as a bearing of the operating handle 12, for example an axis of the operating handle . The operating handle 12 further comprises a handle 15, for example integrally formed with the light entry section 14 or attached as separate part to the light entry section 14. The handle 15 guides light entering the light entry section 14 and reflected within the light entry section 14 such light rays (dotted lines) may leave the handle 15 and so illuminate the handle 15.

The light entry section 14 comprises a light blocking mask 16, which may be formed as a zone of the light entry section 14 as shown in Fig. 1 . The light blocking mask 16 may however also be formed as a separate part, for example a light shade, which is mechanically coupled to the light entry section 14, for example fixed to it, to move together with the operating handle 12.

As shown in Fig. 1 , the operating handle 12 can be moved between three different positions, each being associated with a different status condition A, B or C. Status condition A may be for example ‘circuit closed’, in which the operating handle 12 moves the operating mechanism 10 in a condition, in which contacts (not shown) of the circuit breaker are closed and an electric circuit is such closed. Status condition B may be for example ‘tripped’, in which the circuit breaker was tripped and the operating handle 12 was by the tripped condition and a trip mechanism (not shown) of the circuit breaker brought in a position, in which contacts (not shown) of the circuit breaker are opened and the electric circuit is interrupted. Status condition C may be for example ‘opened’, in which the operating handle 12 moves the operating mechanism 10 in a condition, in which the contacts of the circuit breaker are open, and the electric circuit is interrupted. This can be for example incurred by a manual handling of the handle 15 in contrast to the automatic opening incurred by the trip mechanism.

The operating mechanism 10 further comprises two light sources 18 and 20, for example light emitting diodes, which both emit light with different colors. For example, the light source 18 may emit green light 22, while the light source 20 may emit red light 24. The light sources 18, 20 may be permanently powered throughout the usage of the circuit breaker comprising the operating mechanism 10, particularly if the circuit breaker is supplied with electric power. Thus, the status condition of the circuit breaker may be continuously indicated through the illumination of the handle 15 by the light 22 and 24 emitted by the light sources 18 and 20. The light sources 18 and 20 are fixed with regard to the light entry section 14, for example be fixedly installed in a housing (not shown) of the circuit breaker, so that when the operating handle 12 and the handle 15 as well as the light entry section 14 move, the position of the mask 16 may change with regard to the fixed light sources 18 and 20 as can be seen in Fig. 1 with the different status conditions A to C.

When the circuit breaker is in status condition A, i.e., the handle 15 is moved to an upper position to close the contacts of the circuit breaker and, thus, the electric circuit, the mask 16 is turned with the light entry section 14 so that it blocks the red light 24 emitted by the light source 20. Therefore, only the green light 22 from the light source 18 is coupled into the operating handle 12 through the light entry section 14 and guided to the handle 15, which is illuminated by the green light indicating the status condition A.

When the circuit breaker is in status condition B, i.e., the handle 15 is moved to an middle position to open the contacts of the circuit breaker and, thus, the electric circuit, the mask 16 is turned with the light entry section 14 so that it is in a position in which it does essentially neither block the green light 22 nor red light 24. Therefore, the red light 20 and the green light 22 from the light sources 18 and 20, respectively, are both coupled into the operating handle 12 through the light entry section 14 and guided to the handle 15, which is illuminated by a mixture or combination of the red and green light resulting in a yellow light indicating the status condition B. When the circuit breaker is in status condition C, i.e. , the handle 15 is moved to a lower position to open the contacts of the circuit breaker and, thus, the electric circuit, the mask 16 is turned with the light entry section 14 so that it blocks the green light 22 emitted by the light source 18. Therefore, only the red light 24 from the light source 20 is coupled into the operating handle 12 through the light entry section 14 and guided to the handle 15, which is illuminated by the red light indicating the status condition C.

Thus, with two continuously powered light sources 18 and 20 emitting light with different colors, three differently illuminated status conditions A to C may be indicated, without requiring complex electronics for sensing a position of the operating handle 12 and controlling light emission with the light sources 18 and 20.

Fig. 2 shows another embodiment of an operating mechanism 10’ with three light sources 18, 19 and 20 emitting light of different color, for example green light 22 by light source 18, blue light 23 by light source 19, and red light 24 by light source 20.

In this embodiment, the light blocking mask 16’ is arranged on the light entry section 14 of the operating handle 12 such that status condition A is indicated by green light 22, status condition B by red light 24, and status condition C by a mixture or combination of blue light 23 and red light 24 resulting in a magenta light.

In principle, the embodiment of Fig. 2 could also indicate a fourth condition (not shown) when for example the operating handle 12 is turned upwards such that the mask 16 essentially blocks only the red light 24 and a mixture or combination of the green light 22 and the blue light 23 illuminates the handle 15 resulting in a cyan light.

Also, embodiments are possible in which the operating handle can be moved or brought into a position so that the mask does essentially not block any light emitted from the light sources arranged around the light entry section and a combination or mixture of the light emitted from all light sources can illuminate the handle.

Yet further, embodiments are possible in which not only one mask, but several masks are provided to block light emitted from different light sources.