A) TECHNICAL FIELD
1] The present invention generally relates to electrical power distribution system, and particularly to current limiting circuit breakers. The present invention more particularly relates to the draw-out module for molded case circuit breakers.
B) BACKGROUND OF THE INVENTION
2] It is known that in order to cater to the requirements of distribution and protection of the end application devices, incoming power is routed through various electrical monitoring and controlling devices (hence forth called as switching devices). The use of electrical devices is well known for making, breaking and to provide safety in a typical electrical distribution system. The switching devices are mounted inside an enclosure with all electrical connections made within an enclosure for the necessary distribution and finally the required power is delivered to the end application devices.
[3] The switchgear generally contains circuit breakers of removable or rack out types and are contained in an individual grounded metal compartments. A circuit breaker is an automatically-operated electrical switch designed to protect an electrical circuit from damage caused by overload or short circuit. The circuit breaker must detect a fault condition. Circuit-breaker mounting assembles are equipped with a racking mechanism that properly positions the power circuit breaker and holds it rigidly in connected, test, and fully disconnected positions.
[4] With the advancement of technology and invention of various materials, the switching devices have shown a trend to become smaller for an intended power distribution and protection. Also from the point of view of usage of floor space, the trend is to use minimum space required for the distribution of power with the establishments. The conventional circuit breaker modules do not include any indicator mechanism in order to ensure the safety of operating personnel. The current products are occupying more space in the switchboards. When the circuit breaker is mounted in a horizontal direction or in an angle to the horizontal direction, the circuit breaker would fall down or move rapidly due to inertia of the breaker. When the breaker is not arrested properly in its locked position, the sluggish movements and tilting of the breaker will disturb the contact reliability, which need to be eliminated.
[5] Hence there is a need to develop a safety operating mechanism for plug-in and draw out of the electrical equipments or modules from arc flash hazards.
[6] The above mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.
C) OBJECT OF THE INVENTION
[7] The primary object of the present invention is to develop a draw-out module for molded case circuit breakers.
[8] Another object of the present invention is to develop a draw-out module for molded case circuit breaker which is compact enough and easy for assembling.
0009] Yet another object of the present invention is to develop a draw-out module for molded case circuit breaker, wherein independent breaker movement is not possible between TEST and CONNECTION positions when the breaker is moimted in horizontal or some angled position.
[10] Yet another object of the present invention is to develop a draw-out module for molded case circuit breaker with reduction in size of the draw-out and reduction in number of components.
[11] Yet another object of the present invention is to develop a draw-out module for molded case circuit breaker with a locking handle/lever in the front face of the draw-out.
These and other objects and advantages of the present invention will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings.
D) SUMMARY OF THE INVENTION
[13] The above mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.
0014] The various embodiments of the present invention provide a draw-out module for molded case circuit breaker. The plug-in part is the base of draw-out. The plug-in is having current conducting parts. The draw- out is used to establish connection between the breaker and the plug-in. The Draw out assembly consists of a mechanism, locking, safety trip, position indication, auxiliary connections and pad locking.
[15] According to an embodiment of the present invention, the draw-out is provided with two outer plates and two handles. One is on the left side and another on the right side. The breaker is moved on the outer plate with the help of a bracket arrangement, which is connected to the breaker using mounting screws of the breaker. The bracket comprises two rail-pins on its both sides. The rail pins move on the outer plates with the help of mechanism (two handles). The two rail pins allows the breaker movement only towards and away from the plug-in base. Two handles are connected to make synchronized movement of the breaker on both sides on the breaker.
[16] Normally every draw-out is having only one locking mechanism (primary locking) to arrest the breaker movement whenever the breaker reaches 'a TEST AND 'CONNECTION' position, hi the present invention, one extra locking is provided to enhance the security or normality of breaker movement when draw-out is mounted in horizontal or some angled position in switchboard. This extra locking is called as 'Secondary locking'.
[17] The secondary locking is mounted on one of the handles. The primary locking is mounted in opposite side to secondary locking so that movement and tilting of the breaker are arrested perfectly on both sides and breaker contacts align with plug-in contacts of the base. The secondary locking mechanism includes only one compression spring inside the handle holder so that the secondary locking always locks the handle movement by the slots provided on the left outer plate.
[18] When the operator places the breaker assembly on outer plates to connect, after moving 4mm on the outer plates due to the small force exerted by the operator from 'DISCONNECTION' position, the secondary locking established due to the slot 1 with the help of S2. Then operator should press the handle holder SI with the left force finger lightly so only the breaker will be free to move from that position. HI & H2 components are interlinked with the help of pins. After rotating the handle, 'TEST' position will come. There the primary locking established. After the removal of primary locking also, the secondary locking still established until the operator pressing the handle holder. This feature is very useful in horizontal mounting. The same locking is maintained in the 'CONNECTION' position. In between 'TEST' and 'CONNECTION' positions also the secondary locking is given where the power supply is not established with breaker contacts.
E) BRIEF DESCRIPTION OF THE DRAWINGS
[19] The other objects, features and advantages will occur to those skilled in the art from the following description of the preferred embodiment and the accompanying drawings in which:
[20] FIG. 1 illustrates the front view and the back view of the breaker assembly according to an embodiment of the present invention.
[21] FIG. 2 illustrates the front view of the fork type draw-out with breaker assembly according to an embodiment of the present invention.
[22] FIG. 3 illustrates the sectional view of the fork type draw-out without breaker assembly according to an embodiment of the present invention.
FIG. 4 illustrates the perspective view of the fork type draw-out without breaker assembly showing the secondary locking according to an embodiment of the present invention.
[24] FIG. 5 illustrates another perspective view of the fork type draw-out without breaker assembly showing the secondary locking according to an embodiment of the present invention.
[25] FIG. 6 illustrates the perspective view of the fork type draw-out without breaker assembly with the primary locking at test position according to an embodiment of the present invention.
[26] FIG. 7 illustrates the sectional view of the breaker assembly showing the safety trip according to an embodiment of the present invention.
[27] FIG. 8 illustrates the sectional view of the breaker assembly showing the assembly of the primary locking and position indication components on the cover according to an embodiment of the present invention.
[28] FIG. 9 illustrates the side view and the front view of the fork type draw-out breaker assembly in DISCONNECTED position according to an embodiment of the present invention.
[29]
FIG. 10 illustrates the side view and the front view of the fork type draw-out breaker assembly in TEST position according to an embodiment of the present invention.
[0030] FIG. 11 illustrates the side view and the front view of the fork type draw-out breaker assembly in CONNECTED position according to an embodiment of the present invention.
[0031 ] Although specific features of the present invention are shown in some drawings and not in others. This is done for convenience only as each feature may be combined with any or all of the other features in accordance with the present invention.
F) DETAILED DESCRIPTION OF THE INVENTION
[32] In the following detailed description, reference is made to the accompanying drawings that form a part hereof, and in which the specific embodiments that may be practiced is shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments and it is to be understood that the logical, mechanical and other changes may be made without departing from the scope of the embodiments. The following detailed description is therefore not to be taken in a limiting sense.
[33] The various embodiments of the present invention provide a variable contact locking arrangement for circuit breakers. FIG. 1 illustrates the front and back view of the breaker assembly according to an embodiment of the present invention. The assembly includes a breaker 11 part, a safety trip 12, rail pins 14, mounting screws 15 and the bracket 13. The mounting screws 15 are used to connect breaker 11 and the bracket 13. The breaker knob 16 shown on the front face breaker. The mechanism and the locking are designed such that the operator can take care of the breaker movement. The modularity of components in the cover provides for ease of assembling and manufacturing.
[34] FIG. 2 illustrates the front view of the fork type draw-out with breaker assembly according to an embodiment of the present invention. The locking lever 21 is provided on the front face of the draw-out for easy access to the operator. FIG. 3 illustrates the sectional view of the fork type draw-out without breaker assembly according to an embodiment of the present invention. The plug-in part is the base of draw-out. The plug-in 31 is having the current conducting parts. The draw-out is used to establish connection between the breaker 11 and the plug-in 31. The draw-out is the arrangement which is having a plug-in 31 as the base. The draw out assembly consists of mechanism, locking, safety trip, position indication, auxiliary connections and pad locking. The draw-out is having two outer plates and two handles; one is on the left side and another on the right side. The breaker is moving on the outer plate with the help of bracket arrangement, which is connected to the breaker 11 with the help of mounting screws 15 of the breaker 11. The bracket 13 is having two rail-pins 33 on its both sides. The rail pins 33 moves on the outer plates 38 with the help of the two handles. The two rail pins 33 allow the breaker 11 to move only towards and away from the plug- in 31 base. The two handles Eire connected to make synchronized movement of the breaker 11 on both sides on the breaker 11. Connecting two handles is one of the key features in this invention. It also avoids the tilting of the breaker 11 when it is moving.
FIG. 4 illustrates the perspective of the fork type draw-out without breaker assembly showing the secondary locking according to an embodiment of the present invention. FIG. 5 illustrates another prospective view of the fork type draw-out without breaker assembly showing the secondary locking according to an embodiment of the present invention.
[0036] Normally every draw-out is having only one locking mechanism (primary locking) 44 to arrest the breaker movement whenever the breaker 11 reaches 'TEST AND 'CONNECTION' positions. In this new invention, one extra locking is provided to enhance the security or normality of breaker movement when draw-out is mounted in horizontal or some angled position in switchboard. This extra locking is called as 'Secondary locking'. The secondary locking is mounted on one of the handles (left side handle as shown in FIG. 3). The primary locking 44 is mounted in opposite side to secondary locking so that movement and tilting of the breaker 11 are arrested perfectly on both sides and breaker contacts align with plug-in contacts of the base. Secondary locking mechanism is having only one compression spring 34 inside the handle holder (shown in FIG. 3 & FIG. 5) so that the secondary locking always locks the handle movement by the slots as shown in FIG. 5 provided on the left outer plate 35.
0037] When the operator places the breaker assembly on outer plates to connect, after moving 4mm on the outer plates due to the small force exerted by the operator from 'DISCONNECTION' position, the secondary locking established due to the slot 1 as shown in FIG. 5 with the help of S2 as shown in FIG.4. Then operator should press the handle holder 34 as shown in FIG. 3 with the left forefinger lightly so only the breaker will be fi-ee to move fi-om that position. HI & H2 components are interlinked with the help of pins. After rotating the handle, 'TEST' position will come. There the primary locking 44 established. After the removal of primary locking 44 also, the secondary locking still established (slot 2 shown in FIG. 5) until the operator pressing the handle holder 34. This feature is very useful in horizontal mounting. The same locking is maintained in the 'CONNECTION' position (slot 4 shown in FIG. 5) also. In between 'TEST' and 'CONNECTION' positions where the power supply is not established with breaker contacts (slot 3 shown in FIG. 5).
[38] FIG. 6 illustrates the perspective view of the fork type draw-out without breaker assembly with primary locking 44 at test position according to one embodiment of the present invention. The primary locking 44 components mounted in plastic cover which is fitted to right outer plate 38 as shown in FIG. 3. The primary locking 44 is used to arrest the breaker movement whenever the breaker reaches 'TEST' and 'CONNECTION' positions. One tension spring 61 is connected at other end of the 'lock remover' 21 component as shown in FIG. 8 to plastic cover so that the 'lock remover' 21 component always making touch with right side handle surface. When the breaker reaches the 'TEST' and 'CONNECTION' positions, 'lock remover' 21 component pushes the 'locker' 45 and slots will be there to lock the 'lock remover' 21 component.
[39] Each 'locker' 45 as shown in FIG. 6 is provided with one tension spring 61 as shown in Fig. 6 to hold 'locker' 45 aligned to hinge point of the handle 43. It means 'locker' 45 always move to a particular position due to the spring action. When the operator wants to move further, the lock condition should be removed by lifting the 'lock remover' 21 upwards with the help of fingers. After this, 'lock remover' 21 pushing the 'locker' 45 and then moving along the handle and ready for next locking. In the present invention, the locking is achieved in rotary movement of the handle.
[40] FIG. 7 illustrates the section view of the breaker assembly showing the safety trip. The breaker should be in tripped condition while inserting towards 'CONNECTION' position as well as drawing breaker towards DISCONNECTION position so that abnormal operations can be avoided. This feature is called 'SAFETY TRIP' as shown in FIG. 7. The moverl 74 component always slides over the 'wedge' 40 as shown in FIG. 3 due to the compression spring 73 action. When the moverl 74 moves along the 'wedge' 40, it moves inside the cover2 76. Due to this movement, the mover2 75 touches the trip lever or trip plate or mechanism to trip the breaker. In the present invention, only one spring is used with the cam surface 72. The breaker will be tripped if the movement of the moverl is beyond 4mm from the connection position.
[41] FIG. 8 illustrates the section view of the breaker assembly showing the assembly of primary locking 44 and position indication 42 components on the cover 41 according to an embodiment of the present invention. The primary locking 44 components mounted in plastic cover 41 which is fitted to right outer plate 38 as shown in FIG. 3. This primary locking 44 is used to arrest the breaker movement whenever the breaker reaches 'TEST' and 'CONNECTION' positions. One tension spring 61 is connected at other end of the 'lock remover' 21 component and snap fit 81 is used to fit lock remover 21 to the cover 41 as shown in FIG. 3 & 8 so that the 'lock remover' 21 component always making touch with right side handle surface. Each 'locker' 45 as shown in FIG. 6 is provided with one tension spring to hold 'locker' 45 aligned to hinge point of the handle.
[42] The position of the breaker is clearly shown in front face of the draw-out as shown FIG. 9. The arrow 91 as shown in FIG. 9, FIG. 10 and FIG. 11 moves whenever the breaker moves so that the operator can know still how much distance to travel between positions. In the present new invention, only less material is used in the plastic part and also the modularity is maintained. The fixing of the position indication components to the cover prevents the components from coming out.
[43] FIG. 9 illustrates the side view and the front view of the fork type draw-out breaker assembly in DISCONNECTED position according to an embodiment of the present invention. FIG. 10 illustrates the side view and the front view of the fork type draw-out breaker assembly in TEST position according to an embodiment of the present invention. FIG. 11 illustrates the side view and the front view of the fork type draw-out breaker assembly in CONNECTED position. The position of the breaker is clearly shown in the front face of the draw-out. In the present invention, an arrow as shown in FIG. 9, FIG. 10 and FIG. 11 moves whenever the breaker moves so that the operator can know still how much distance to travel between the positions.
G) ADVANTAGES OF THE INVENTION
0044] The size of the draw-out in the present invention is reduced to the minimum extent and the assembly is simple and modular. The number of joints and the number of components during the assembly is reduced to the maximum extent leading to an increase in the reliability.
[45] Locking the breaker in three positions is optimized so that the breaker can be arrested perfectly within the draw-out. When the breaker is mounted in horizontal direction or with an angle to horizontal line, there is no chance for the breaker to fall down. The mechanism and locking is designed such that the operators can always take care of the breaker movement. The assembly of the present invention achieves higher mechanical stability, consistency and optimum utilization of contact spring force. Also, both the handles of the draw-out are connected together, so that the movement of the breaker is arrested properly.
[46] Although the invention is described with various specific embodiments, it will be obvious for a person skilled in the art to practice the invention with modifications. However, all such modifications are deemed to be within the scope of the claims.
[0047] It is also to be understood that the following claims are intended to cover all of the generic and specific features of the present invention described herein and all the statements of the scope of the invention which as a matter of language might be said to fall there between.

What is claimed is:
1. A draw-out module for molded case circuit breaker comprising;
A draw out mechanism;
two outer plates provided in the draw out mechanism; two handles provided in the draw out mechanism; a bracket connected to the outer plates; a locking mechanism mounted on the handles; a primary locking provided in the locking mechansim; a secondary locking provided in the locking mechanism; a safety trip mechanism; a locking lever; and a mounting screw.
2. The module according to claiml, wherein the two outer plates are provided on the left hand side and the right hand side of the draw out mechanism.
3. The module according to claiml, wherein the two handles are provided on the left hand side and the right hand side of the draw out mechanism.
4. The module according to claim 1, wherein the two handles are connected
to make a synchronous movement of the breaker and to avoid the tilting of the breaker during movement.
5. The module according to claim 1, the bracket has two rail-pins which are mounted on both the sides to allow the breaker movement only towards and away from a plug-in base.
6. The module according to claim 1, wherein the secondziry locking is mounted on one of the handles
7. The module according to claim 1, wherein the primary locking is mounted
in opposite side to secondary locking for perfectly arresting the movement and tilting of the breaker.
8. The module according to claim 1, wherein the outer plate provided on the
left hand side of the draw out mechanism has slots for secondary locking.
9. The module according to claim 1, wherein in secondary locking has a handle holder provided with a compression spring to lock the handle movement by the slots.
10. The module according to claim 1, wherein two tension springs are provided in the primary locking to arrest the breaker movement whenever the breaker reaches test and connection positions.
11. The module according to claim 1, wherein the safety trip mechanism is provided in the breaker to avoid abnormal operations.
12. The module according to claim 1, wherein an arrow is provided on the front face of the draw-out to indicate the distance for travel between the positions.