Claims:
1. An interlocking assembly (100) for electrical contactors, the electrical contactors being a first contactor (150A) and a second contactor (150B), the interlocking assembly (100) comprising:
• a housing (10) being separable into two identical left and right halves
(10A, 10B);
• a cover (20) adapted for enclosing the housing (10), the cover (20) being separable into two identical left and right halves (20A, 20B);
• a first actuator (30) assembled between the left halves (10A, 20A of the housing (10) and the cover (20), the first actuator (30) having a first slot (22) on one side thereof and a first projection (24) on opposite side thereof, the first projection (24) adapted to protrude through the left half (20A) of the cover (20) to engage with a contact supporting moving element of the first contactor (150A);
• a second actuator (40) assembled in the right halves (10B, 20B) of the housing (10) and the cover (20), the second actuator (40) having a second slot (32) on one side thereof and a second projection (34) on opposite side thereof, the second projection (34) adapted to protrude through the right half (20B) of the cover (20) to engage with a contact supporting moving element of the second contactor (150B); and
• an assembly of two fulcrums (50, 60) assembled between the two halves of the housing (10A, 10B), each fulcrum (50, 60) having a projection (42, 52) configured at one end thereof to protrude through the housing (10) for engaging with the slots (22, 32) of the actuators (30, 40),

wherein, when the contact supporting moving elements of both contactors (150A, 150B) are in open states, both actuators (30, 40) move therewith in upward directions engaging the projections (42, 52) into the slots (22, 32) thereby arresting/locking the motion of both fulcrums (50, 60) and thus preventing simultaneous closing of both contactors (150A, 150B);

wherein, when one of the contact supporting moving element is in the open state and the other contact supporting moving element is in a closed state, the actuator (30/40) engaged with the contact supporting moving element in the open state travels therewith in upward direction transmitting the motion to the fulcrum (50/60) through the slot (22/32) resulting in angular rotational motion of one of the fulcrums (50/60) around its own axis that in turn arrests/locks the motion of other fulcrum (60/50) thereby preventing the other contactor 150B/150A) from getting closed.

2. The interlocking assembly (100) as claimed in claim 1 is sandwiched and directly mounted on the contactors (150A, 150B).

3. The interlocking assembly (100) as claimed in claim 1, wherein the actuators (30, 40) and the assembly of two fulcrums (50, 60) are made of a thermoplastic material.

4. The interlocking assembly (100) as claimed in claim 1, wherein the actuators (30, 40) are placed in the identical halves (10A, 10B) of the housing (10) such that the first projection (24) and the second projection (34) face opposite side of each other.
, Description:FIELD OF THE INVENTION

The present invention generally relates to electrical contactors, and more particularly to an interlocking assembly for electrical contactors.

BACKGROUND OF THE INVENTION

Electrical contactor is used as switching device in switchgears for making and breaking of an electric circuit. In particular, a pair of electrical contactors gets used in case of a main and a standby electrical supply in the system. At a given time only one electrical contactor shall close and make electrical circuit. Another electrical contactor shall not get closed. Only if first contactor is open then second electrical contactor shall close. Currently available interlocking arrangements involve too many components that increase the cost as well as the level of difficultly at the time of manufacturing.

Hence, there exists a need to provide a mechanical interlocking assembly for electrical contactors that overcomes the above mentioned drawbacks of the prior art.

OBJECTS OF THE INVENTION

An object of the present invention is to provide an improved unique sandwich type mechanical interlocking arrangement for preventing simultaneous closing of pair electrical contactors.

Another object of the present invention is to provide an easy to manufacture interlock with fewer components to offer higher productivity and also higher life during operation.
SUMMARY OF THE INVENTION

Accordingly, the present invention provides an interlocking assembly for electrical contactors. The electrical contactors include a first contactor and a second contactor. The interlocking assembly is sandwiched and directly mounted on the contactors. The interlocking assembly comprises a housing, a cover, a first actuator, a second actuator and an assembly of two fulcrums. The housing is separable into two identical left and right halves. The cover is adapted for enclosing the housing. The cover is separable into two identical left and right halves.

The first actuator is assembled between the left halves of the housing and the cover. The first actuator includes a first slot on one side thereof and a first projection on opposite side thereof. The first projection is adapted to protrude through the left half of the cover to engage with a contact supporting moving element of the first contactor.

The second actuator is assembled in the right halves of the housing and the cover. The second actuator includes a second slot on one side thereof and a second projection on opposite side thereof. The second projection is adapted to protrude through the right half of the cover to engage with a contact supporting moving element of the second contactor. The actuators are placed in the identical halves of the housing such that the first projection and the second projection face opposite side of each other.

The assembly of two fulcrums is assembled between the two halves of the housing. Each fulcrum includes a projection configured at one end thereof to protrude through the housing for engaging with the slots of the actuators. The actuators and the assembly of two fulcrums are made of a thermoplastic material.

When the contact supporting moving elements of both contactors are in open states, both actuators move therewith in upward directions engaging the projections into the slots thereby arresting/locking the motion of both fulcrum and thus preventing simultaneous closing of both the contactors.

When one of the contact supporting moving element is in the open state and the other contact supporting moving element is in a closed state, the actuator engaged with the contact supporting moving element in the open state travels therewith in upward direction transmitting the motion to the fulcrum through the slot resulting in angular rotational motion of one of the fulcrum around its own axis that in turn arrests/locks the motion of other fulcrum thereby preventing the other contactor from getting closed.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features as well as the advantages of the invention will be clear from the following description.
In the appended drawings:
Figure 1 illustrates a unique sandwich type mechanical interlocking mounting arrangement between a pair of contactors, in accordance with the present invention;

Figure 2 shows an interlocking assembly for electrical contactors, in accordance with the present invention;

Figure 3 shows an exploded view of the interlocking assembly of figure 2;

Figure 4 shows an actuator and a fulcrum of the interlocking assembly of figure 2;

Figure 5 shows the positions of the fulcrums when both the contactors are in open states, in accordance with the present invention; and
Figure 6 shows the positions of the fulcrums when one of the contactors is in a closed state, in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiment.

The present invention provides an interlocking assembly for electrical contactors. The interlocking assembly is a unique sandwich type mechanical interlocking arrangement mounted between a pair of contactors for preventing simultaneous closing thereof. The interlocking assembly is easy to manufacture due to fewer components involved.

The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures.

Referring to figures 1-6, an interlocking assembly (100) for electrical contactors, in accordance with the present invention is shown. The electrical contactors include a first contactor (150A) and a second contactor (150B). Specifically, the interlocking assembly (100) is a unique sandwich type mechanical interlocking arrangement mounted on and sandwiched between the contactors (150A, 150B) as shown in figure 1. The interlocking assembly (100) is capable of being modified to provide interlocking for multiple contactors as per alternate embodiments of the present invention.

The interlocking assembly (100) will be now described in more detail with reference to figures 2, 3 and 4. The interlocking assembly (100) comprises a housing (10), a cover (20), a first actuator (30), a second actuator (40) and an assembly of two fulcrums (50, 60).

The housing (10) is separable into two identical left and right halves (10A, 10B). The cover (20) is adapted for enclosing the housing (10). The cover (20) is separable into two identical left and right halves (20A, 20B).

The first actuator (30) is assembled between the left halves (10A, 20A) of the housing (10) and the cover (20). The first actuator (30) includes a unique shaped first slot (22) on one side thereof and a first projection (24) on opposite side thereof. The first projection (24) is adapted to protrude through the left half (20A) of the cover (20) to engage with a contact supporting moving element (not shown) of the first contactor (150A).

The second actuator (40) is assembled in the right halves (10B, 20B) of the housing (10) and the cover (20). The second actuator (40) includes a unique second shaped slot (32) on one side thereof and a second projection (34) on opposite side thereof. The second projection (34) is adapted to protrude through the right half (20B) of the cover (20) to engage with a contact supporting moving element (not shown) of the second contactor (150B).

The actuators (30, 40) are placed in the identical halves (10A, 10B) of the housing (10) such that the projections (24, 34) face opposite side of each other. In an embodiment, the actuators (30, 40) are made up of a thermoplastic material. The actuators (30, 40) are capable of moving in upward direction during an open state of the contactors (150A, 150B) and moving in downward direction during a closed state of the contactors (150A, 150B).

The assembly of two fulcrums (50, 60) is assembled between the two halves (10A, 10B) of the housing (10) to engage with the actuators (30, 40). Specifically, the fulcrums (50, 60) are continuously engaged with the respective actuators (30, 40) during OPEN-CLOSE operation of contactors (150A, 150B). Each fulcrum (50, 60) includes a projection (42, 52) configured at one end thereof to protrude through the housing (10) for engaging with the slots (22, 32) of the actuators (30, 40). Thus, the fulcrums (50, 60) at one end get engaged with the actuators (30, 40) at unique shaped slots (22, 32). In an embodiment, the actuators (30, 40) and the assembly of two fulcrums (50, 60) are made of a thermoplastic material. The fulcrums (50, 60) are placed in such way to undergo rotation in both clockwise and counterclockwise directions around their axis in angular direction during OPEN-CLOSE operation of the contactors (150A, 150B).

When both contactors (150A, 150B) as well as their respective contact supporting moving elements are in open states as shown in figure 5, both actuators (30, 40) move therewith in upward directions engaging the projection (42) into the first slot (22) and the projection (52) into the second slot (32) thereby arresting/locking the motion of both fulcrums (50, 60) and thus preventing simultaneous closing of both contactors (150A, 150B).

When one of the contactors (150A/150B) as well as its respective contact supporting moving elements is in open state as shown in figure 6 or when one of the contact supporting moving element is in the open state and the other contact supporting moving element is in a closed state, the actuator (30/40) engaged with the contact supporting moving element in the open state travels therewith in upward direction transmitting the motion to the fulcrum (50/60) through the slot (22/32) resulting in angular rotational motion of one of the fulcrum (50/60) around its own axis that in turn arrests/locks the motion of other fulcrum (60/50) thereby preventing the other contactor (150B/150A) from getting closed.

ADVANTAGES OF THE INVENTION

1. The interlocking assembly (100) is an improved unique sandwich type mechanical interlock which directly gets mounted on the contactors (150A, 150B).
2. Unique profiles of the actuators (30, 40) and the fulcrums (50, 60) ensure positive interlocking. The actuators (30, 40) has unique shaped slots (22, 32) for engaging the fulcrums (50, 60) while transmitting motion. The assembly of unique profile fulcrums (50, 60) comprises shape i.e. projections (42, 52) for angular motion at certain axis and provision for locking while getting interlocked.
3. The interlocking assembly (100) due fewer components is easy for manufacturing and offers higher productivity. Further, less number of components provides higher life during operation.
4. The interlocking assembly (100) besides providing interlocking function is also capable of being used for auxiliary contacts like NO (normally open) and NC (normally closed).

The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, and to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but such omissions and substitutions are intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention.