FIELD OF INVENTION
The present invention in general, relates to the field of circuit breakers and auxiliary contact devices. More particularly, it relates to the designing of two components, naming direction convertor and latch- RCCB so as to make single auxiliary contact compatible with different mechanisms
BACKGROUND AND PRIOR ART OF THE INVENTION
The present invention discloses an auxiliary contact being able to constitute either an auxiliary contact of a miniature circuit breaker or an auxiliary contact for residual current circuit breaker, keeping almost ali the parts which constitute such an auxiliary device, identical and at the same time fulfilling different tripping requirements by incorporating two separate components, direction convertor and latch RCCB direction convertor is used when auxiliary constitutes an auxiliary for MCBs and latch RCCB is used when auxiliary constitutes an auxiliary for RCCBs.
Referring to Fig- 1, which shows the prior art & prime design of a latching memoer compatible with only one of the range of a Miniature Circuit Breaker, rating 80A - 125A In order to make it compatible with all range of our miniature circuit breaker and Residual Current circuit breakers, 2 new components have been developed
The main problem which needs to be addressed is to meet different tripping requirements of different designs, since all the designs have different mechanisms and different tripping points, which engages with auxiliary contact mechanism, by keeping the main tripping point of the auxiliary contact at the same location where it engages and disengages the knob link to trip the complete system and at the same time satisfies the tripping requirements of different products The present invention provides an auxiliary contact which can be used with our range of miniature circuit breaker and residual current circuit breaker keeping almost all parts which constitute auxiliary contact device, identical
OBJECTS OF THE INVENTION
The Principal object of the present invention is to provide an auxiliary device that is
common for our miniature circuit breakers and residual current circuit breaker
Yet another object of the present invention is to achieve the tripping requirements of
different designs in a single unit by a common mechanism, by keeping majority of parts
identical.
still another object of the present invention is to provide additional test button to check the proper functionality of the auxiliary contact.
SUMMARY OF INVENTION
An embodiment of the present invention comprises making an existing auxiliary contact compatible with both miniature circuit breakers and residual current circuit breaker (figures 2 to 5).
In contrast to circuit breaker, which has an operating mechanism for closing and opening switching contacts, and a trip latch which works the operating mechanism when released to open the switching contacts, the problem arise in integrating different mechanism behaviors and tripping points of different designs of circuit breakers, in a singie unit of half module, which shall be of 9.0 mm. To counteract this problem, two additional components are designed and used to suite the different mechanism and tripping behaviors of circuit breakers.
In an embodiment of the present invention when auxiliary contact is attached with the
miniature circuit breaker, referring figures 2 & 3, having rating from 0.5 A - 63 A. a
component called direction converter is used.
In another embodiment of the present invention the direction converter has a pin which
is pressed fit at one end and the other end rotates about a hinge point provided in case and
cover of an auxiliary contact.
In yet another embodiment of the present invention the pin of the direction converter
directly fits behind the latching fork of the miniature circuit breaker
In still another embodiment of the present invention the complete assembly of the
direction converter and the pin is spring loaded and automatically moves by the action of
the spring force, as the latching fork rotates about its hinge point
In another embodiment of the present invention the auxiliary contact for miniature
circuit breaker with the direction converter where the direction converter and pin assembly
moves by an angle of 30° in counter clockwise direction by the action of latching fork to trip
the main latch of auxiliary contact, through CAM.
In an embodiment of the present invention when auxiliary contact is attached with the
residual current circuit breaker, referring figures 4 & 5, a component called latch - RCCB is
used
In another embodiment of the present invention the auxiliary contact device for residual
circuit breaker in which the said device has the latch - RCCB, a pin is pressed fit at one end
and the tension spring fits at the other end, wherein the second end of the spring is hooked
in the pillar provided in the case of auxiliary contact.
In yet another embodiment of the present invention the tension spring restricts the
assembly of latch and pin only in the translation motion.
In still another embodiment of the present invention an auxiliary contact for circuit
breaker in which the pin fits in the window provided in the residual current circuit breaker,
where it interferes with the knob link of residual current circuit breaker, at abnormal
conditions of current and voltage, causing the pin to move by a distance of 4mm. this
further drives latch - RCCB against the spring force to trip the device.
In another embodiment of the present invention the auxiliary contact in which the CAM
profile is designed in the front portion of latch - RCCB, which further interferes with the
main latch to trip the mechanism of auxiliary contact.
In yet another embodiment of the present invention, to periodically check the correct
working of the mechanism and functionality of auxiliary contact, a test button is provided
which is spring loaded, with one end fixed in the casing and the other end moves in the
guiding chamber provided in the case & cover.
In still another embodiment of the present invention when the said test button is
pressed through finger or tool, it moves in the guided path to directly hit the main latch,
thereby causing the mechanism to trip, which further switches the contacts of the auxiliary
trip device, to check the continuity and proper function of the trip device
BRIEF DESCRIPTION OF FIGURES
It may be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments.
Figure 1 shows the prior art;
Figures 2 to 5 each illustrates the tripping points, window openings & connectivity of
auxiliary trip device with miniature circuit breaker and residual current circuit breaker,
Figure 6 shows the assembly of direction converter & pin;
Figure 7 shows the internal isometric view of auxiliary contact for miniature circuit breaker
with direction converter, pin & latching fork;
Figures 8 & 9 show the internal view of auxiliary contact for miniature circuit breaker with
direction converter in tripped position,
Figure 10 shows the hinge point of latching fork, with direction converter & pin;
Figure 11 shows the assembly of latch - RCCB & pin, with tension spring used when
auxiliary contact is connected with residual current circuit breaker;
Figure 12 illustrates the internal details of the mechanism of auxiliary contact when
connected with residual current circuit breaker, showing knob link, latch - RCCB & pin;
Figure 13 shows auxiliary contact in tripped condition;
Figure 14 shows the CAM profile designed in Latch - RCCB;
Figures 15 to 17 show details of test button & it's working to check the proper functionality
of the mechanism of auxiliary contact.
DETAILED DESCRIPTION OF INVENTION
Accordingly the present invention discloses a common auxiliary contact device that is associated with the circuit breakers, notably miniature circuit breakers and residual current circuit breaker. A single existing auxiliary contact is made compatible with both miniature circuit breaker and Residual current circuit breaker. The common auxiliary switching unit has components to suit different tripping points and window for miniature circuit breaker and Residual current circuit breaker.
The auxiliary contact device being able to constitute either an auxiliary contact of a miniature circuit breaker or an auxiliary contact for residual current circuit breaker, whereas majority of parts which constitute such an auxiliary contact are identical for all types of auxiliary contact devices which can thus be constituted
Referring figures 6 to 10, the present invention provides an auxiliary contact for a circuit breaker that has a component called the direction converter (1), in which a pin (2) is pressed fit at one end and the other end rotates on a hinge point provided in case and cover of auxiliary contact.
The component is designed in such a way that the pin (1) directly fits behind the latching fork (3) of the circuit breaker, as shown in figure 7. The complete assembly of direction converter (1) and the pin (2) is spring loaded and thus automatically rotates in counter clockwise direction, by the action of the spring force, as the latching fork (3) rotates about its hinge point (12), as shown in figurelO. Direction converter (1) and the pin (2) assembly rotates by 30° in clockwise direction, with reference to figure 7, by the action of latching fork (3) to trip the main latch (10) of auxiliary contact, through CAM, as shown in figures 8 & 9 Referring to figure 7, trip force of 800 grams is obtained at the point behind latching fork (3), where direction converter pin (2) rests. This force is sufficient enough to trip the auxiliary contact, by CAM & Follower action, as explained earlier at the main latch point (13), since the force required at this point is 80-100 grams. Figures 8 & 9 show the position of direction converter in trip condition and interference between direction converter
(1) and main latch (10).
Referring to figures 11 to 14, the present invention provides an auxiliary contact for residual circuit breaker which has a component latch - RCCB (6), in which a pin (7) is pressed fit at one end and the tension spring (8) fits at the other end. The second end of the spring (8) is hooked in the pillar provided in the case of auxiliary contact The tension spring (8) provides only the translation motion of the assembly of latch - RCCB (6) & pin (7)
Fig. 13 shows the position of latch - RCCB, pin & knob link (9) of RCCB. The pin (7) fits in the window provided in the residual current circuit breaker, where it interferes with the knob link (9) of residual current circuit breaker, at abnormal conditions of current and voltage. This interference causes the pin (7) to move by 4mm, which further drives the latch - RCCB (6) against the spring force. The CAM profile (14) as shown in figure 14 is designed in the front portion of latch - RCCB (6), which further interferes with the main latch (10), as shown in figure 13 in such a way that it trips the mechanism of auxiliary contact. Fig 13 shows the auxiliary contact in tripped condition.
Trip force of 800 to 1000 grams is obtained at the point behind knob link (9), where latch assembly pin rests, which is sufficient enough to trip the auxiliary contact at the main latch point (13), since the force required at this point is 80 to 100 grams
Referring to fig. 15 & 16, the present invention also provides an auxiliary contact device with a test button (15) tripping mechanism to check the functionality of the device periodically A component -called test button (15), which is spring (16) loaded, with one of its end fixed in the casing and moves in the guiding chamber & restricted by 2-walls (17) & (18) is provided. Referring to figure 17, when pressed through a finger or a tool, as shown by the arrow, test button (15) moves in the guided path, restricted by two walls (17) & (18) to directly hit the main latch (10), which causes the mechanism to trip because of CAM & follower connection, which further switches the contacts of the auxiliary device, to check the continuity and proper function of the trip device. The main advantage of test button is to check the circuit tripping without the manual closing of the operating handle (19).
Various other modifications and alterations in the structure and method of operation of this invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. It is intended that the following claims define the scope of the present invention and that structures and methods within the
scope of these claims and their equivalents be covered thereby.

WE CLAIM
1. An external auxiliary switching unit attached to a circuit breaker for remote indication of electrical signals in ON/OFF state of the circuit breaker, comprising of a case (21) and a switching mechanism, designed to be associated with circuit breakers, notably miniature circuit breakers and residual current circuit breaker, and means to achieve different tripping behaviors of different designs in a single unit.
2. An auxiliary contact device of circuit breaker according to claim 1, when attached with miniature circuit breaker, direction converter (1) is used and when it is attached with residual current circuit breaker, latch - RCCB (6) is used.
3. An auxiliary contact device for miniature circuit breaker according to claim 2. wherein the said member is a direction converter, which has a pin (2) pressed fit at one end and the other end rotates about a hinge point (19) provided in case (21) and cover of the trip device. The pin of direction converter directly fits behind the latching fork (3) of miniature circuit breaker.
4. An auxiliary contact device for miniature circuit breaker according to claim 3, wherein the complete assembly of direction converter & pin is spring loaded in such a way that it automatically rotates about the hinge point (19), under the action of spring force, as the latching fork rotates about its hinge point (12).
5. An auxiliary contact device for miniature circuit breaker according to claim 3, wherein the
assembly of direction converter and pin moves by an angle of 30' in clockwise direction,
with reference to figure 7 to trip the main latch (10) of auxiliary contact, through
CAM/Follower action
6. An auxiliary contact device for residual current circuit breaker according to claim 2, wherein the said member is latch - RCCB (6), which has a pin (7), pressed fit at one end and the tension spring (8) fits at the other end, wherein the second end of the spring is hooked in the pillar (20) provided in the case of auxiliary contact.
7. An auxiliary contact device for residual current circuit breaker according to any of the preceding claims, wherein tension spring (8) restricts the motion of latch - RCCB (6) & Pin (7), only in translation direction
8. An auxiliary contact device for residual current circuit breaker according to claim 7, wherein the pin (7) fits in the window provided in the residual current circuit breaker, which interferes with the knob link (9) of residual current circuit breaker, causing the pin to move by a distance of 4mm, this further drives the latch - RCCB (6) against the spring force.
9. The auxiliary contact device for residual circuit breaker according to any of the preceding claims, wherein the CAM profile (14) designed in the front portion of latch -RCCB (6) in such a way that it interferes with the main latch (10) to trip the mechanism of
auxiliary contact.
10. An auxiliary contact for miniature circuit breaker and residual current circuit breaker according to claim 1, wherein a component namely, test button (15) is provided to check the proper functionality of the trip device. When pressed through finger or tool, test button (15) moves against the force generated by spring (16) in the guided chamber, restricted by two walls (17) & (18) to hit the main latch (10), which causes disengagement of knob link (11) and trips the mechanism which results in the contact switching.