Abstract:
An assembly designed for connecting a motor operator mechanism to side frames of a circuit breaker operating mechanism is disclosed. The assembly comprising a plate connected between the side frames of the operating mechanism and a bracket portion secured to the plate and engages the motor operating mechanism. The bracket portion couples and aligns the motor operator mechanism and the circuit breaker operating mechanism.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a motor operator, and, more particularly, to a motor operator for circuit breakers. 
     It is known in the art to provide molded case circuit breakers for electrical systems. The circuit breaker is operative to disengage the electrical system under certain operating conditions. The use of motor operators to allow the motor-assisted operation of electrical circuit breakers is well known. The motor operator allows the circuit breaker to be operated remotely and to be opened, closed or reset after tripping of the circuit breaker. 
     The motor operator is typically secured to the top of a circuit breaker housing. A lever within the motor operator mechanically interacts with a circuit breaker operating handle, which extends from the circuit breaker housing. The lever is operatively connected to a motor within the motor operator. The motor drives the lever, which, in turn, moves the operating handle to operate the circuit breaker. The operating handle is moved between “on”, “off”, and “reset” positions, depending on the rotational direction of the motor. 
     A plurality of buttons external to the motor operator controls electrical current to the motor. The rotational direction of the motor is changed depending on which of these buttons is selected by operating personnel. Thus, the operating personnel can select one button to place the operating handle in the “on” position, and another button to place the operating handle in the “off” or “reset” positions. 
     When the handle is moved to the “on” position, electrical contacts within the circuit breaker are brought into contact with each other, allowing electrical current to flow through the circuit breaker. When the handle is moved to the “off” position, the electrical contacts are separated, stopping the flow of electrical current through the circuit breaker. When the handle is moved to the “reset” position, an operating mechanism within the circuit breaker is reset, as is necessary after the operating mechanism has tripped in response to an overcurrent condition in the electrical circuit being protected by the circuit breaker. 
     Due to the mounting of the motor operator onto the case of the circuit breaker, excessive lost motion can result between the motor operator and the circuit breaker under extreme operational loads. Excessive motion caused by the motor operator not being rigidly secured to the circuit breaker can result in excessive lost motion between the motor operator and the circuit breaker such that the motor operator is unable to sufficiently move the handle in order to turn the circuit breaker to the desired position (ie. off, on, reset). 
     BRIEF SUMMARY OF THE INVENTION 
     The above discussed and other drawbacks and deficiencies are overcome or alleviated by an assembly for connecting a motor operator mechanism to side frames of a circuit breaker operating mechanism. The assembly comprising a plate connected between the side frames of the operating mechanism and a bracket portion secured to the plate and engages the motor operating mechanism. The bracket portion couples and aligns the motor operator mechanism and the circuit breaker operating mechanism. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will now be described, by way of example, with reference to the following FIGURES, in which: 
     FIG. 1 is a perspective view of a circuit breaker; 
     FIG. 2 is an exploded view of the circuit breaker of FIG. 1; 
     FIG. 3 is a perspective view of a motor operator mechanism mounted on a front face of the circuit breaker of FIG. 1; 
     FIG. 4 is a perspective view of the circuit breaker and the motor operator mechanism of FIG. 3 where the motor operator mechanism is shown in a retracted position; 
     FIG. 5 is an internal side view of the motor operator mechanism and circuit breaker of FIG. 4; 
     FIG. 6 is a perspective assembly view of a mounting base and a mounting assembly; 
     FIG. 7 is a perspective view of a circuit breaker operating mechanism and a plate and a bracket portion of the mounting assembly of FIG. 6; and 
     FIG. 8 is a perspective view of the plate of the mounting assembly of FIG.  6 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to FIGS. 1 and 2, a circuit breaker  20  is shown. Circuit breaker  20  generally includes a molded case, shown generally at  10 , having a top cover  22  attached to a mid cover  24  coupled to a base  26 . An opening  28 , formed generally centrally within top cover  22 , is positioned to mate with a corresponding mid cover opening  30 , which is accordingly aligned with opening  28  when the mid cover  24  and the top cover  22  are coupled to one another. 
     In a 3-pole system (i.e., corresponding with three phases of current), three rotary cassettes  32 ,  34  and  36  are disposed within base  26 . Cassettes  32 ,  34  and  36  are commonly operated by an interface between an operating mechanism  38  via a cross pin  40 . Operating mechanism  38  is positioned and configured atop cassette  34 , which is generally disposed intermediate to cassettes  32  and  36 . Operating mechanism  38  operates substantially as described herein and as described in U.S. patent application Ser. No. 09/196,706 entitled “Circuit Breaker Mechanism for a Rotary Contact Assembly”. 
     A toggle handle  44  extends through openings  28  and  30  and allows for external operation of cassettes  32 ,  34  and  36 . Examples of rotary contact structures that may be operated by operating mechanism  38  are described in more detail in U.S. patent application Ser. Nos. 09/087,038 and 09/384,908, both entitled “Rotary Contact Assembly For High-Ampere Rated Circuit Breakers”, and U.S. patent application Ser. No. 09/384,495, entitled “Supplemental Trip Unit For Rotary Circuit Interrupters”. Cassettes  32 ,  34 ,  36  are typically formed of high strength plastic material and each include opposing sidewalls  46 ,  48 . Sidewalls  46 ,  48  have an arcuate slot  52  positioned and configured to receive and allow the motion of cross pin  40  by action of operating mechanism  38 . In a 3-pole system (i.e., corresponding with three phases of current), three rotary cassettes  32 ,  34  and  36  are disposed within base  26 . Cassettes  32 ,  34  and  36  are commonly operated by an interface between an operating mechanism  38  via a cross pin  40 . Operating mechanism  38  is positioned and configured atop cassette  34 , which is generally disposed intermediate to cassettes  32  and  36 . Operating mechanism  38  operates substantially as described herein and as described in U.S. patent application Ser. No. 09/196,706 entitled “Circuit Breaker Mechanism for a Rotary Contact Assembly”. 
     A toggle handle  44  extends through openings  28  and  30  and allows for external operation of cassettes  32 ,  34  and  36 . Examples of rotary contact structures that may be operated by operating mechanism  38  are described in more detail in U.S. patent application Ser. Nos. 09/087,038 and 09/384,908, both entitled “Rotary Contact Assembly For High-Ampere Rated Circuit Breakers”, and U.S. patent application Ser. No. 09/384,495, entitled “Supplemental Trip Unit For Rotary Circuit Interrupters”. Cassettes  32 ,  34 ,  36  are typically formed of high strength plastic material and each include opposing sidewalls  46 ,  48 . Sidewalls  46 ,  48  have an arcuate slot  52  positioned and configured to receive and allow the motion of cross pin  40  by action of operating mechanism  38 . 
     Referring to FIG. 3, a motor operator mechanism shown generally at  60  is mounted on a mounting base  62  which is secured to the mid cover  24 . When it is desired to mount the motor operator mechanism  60  onto a front face  64  of the circuit breaker  10 , the top cover  22  is typically replaced by the mounting base  62 . Motor operator mechanism  60  affords the capability of either local manual circuit breaker operation or remotely initiated motorized circuit breaker operation. 
     Referring to FIGS. 4 and 5, the motor operator mechanism  60  is shown in a retracted position disengaged from the toggle handle  44 . When in the disengaged position, various accessories (not shown), such as but not limited to auxiliary switches, may be installed within recesses  66  located within the mounting base  62 . 
     Motor operator mechanism  60  includes a case and two side frames  68 ,  70  (shown in phantom) mounted within the case. The side frames  68 ,  70  provide support for the motor operator mechanism  60 , in particular the mechanical structure, such as handle drive rollers (not shown), which move the toggle handle  44  to a desired position (ie. off, on, reset). Each side frame  68 ,  70  includes an edge  72  traversing from an end  74  located on the line side to an end  76  located on the load side. Located along edge  72  of each side frame  68 ,  70  and proximate respective end  76  is a recess  78  formed therein. Preferably, each respective recess  78  is formed between projections  80 ,  82  extending outward and side-by-side from each edge  72  of each respective side frame  68 ,  70 . Located at end  74  of edge  72  of each side frame  68 ,  70  is an extension  84  having an aperture  86 . 
     Referring to FIG. 6, the mounting base  62  is shown in detail. The mounting base  62  includes a main body portion  92  having an opening  94 , formed generally centrally within the mounting base  62 . Opening  94  is positioned to mate with a corresponding mid cover opening  30  through which the toggle handle  44  protrudes. When the mounting base  62  is coupled with the mid cover  24 , openings  94 ,  30  are accordingly aligned one another. The mounting base  62  also includes two openings  96 ,  98  on opposing sides of opening  94  to allow access for mounting electrical accessories when the motor operator mechanism  60  is in the retracted position (FIG.  4 ). The mounting base  62  further includes an end  102  located on the load side and an end  100  located on the line side. Located between ends  100 ,  102  are respective sides  210  and  212 . Preferably, sides  210 ,  212  are parallel to each other and with the ends  100 ,  102  form a generally rectangular shape. Located along end  102  proximate to side  210  is a projection  214  having a hole  216 . Located along end  102  proximate to side  212  is a projection  218  having a hole  220 . Adjacent opening  94  and located at end  100  is a cutout portion  104  that extends through the mounting base  62 . FIG. 6 also shows a portion  106  of the mid cover  24  located on the load side that includes two apertures  108 ,  110 . 
     A bracket portion is shown generally at  112 . Bracket portion  112  includes a base  114  having an end  116  and an opposing end  118 . Base  114  also includes a surface  120  and an opposing surface  122 . Extending outward from end  118  and surface is a leg  124 . Extending outward from end  116  is a leg  126 . The legs  124 ,  126  and base  114  are generally planar with each leg  124 ,  126  having a free end  128 . Located within the base  114  are preferably two apertures  130 ,  132  that extend through surfaces  120 ,  122 . Aligned with apertures  130 ,  132  are respective bushings  134 ,  136 , preferably made of steel that extends outward from surface. The bushings  134 ,  136  may be riveted or welded onto the surface. 
     Referring to FIG. 7, operating mechanism  38  is shown. Operating mechanism  38  includes side frames  140 ,  142  generally parallel to each other as mounted within the operating mechanism  38 . Each side frame  140 ,  142  includes a respective opening  144 ,  146 . Positioned and secured between side frames is a plate  150  as will be detailed in the description of the assembly of the motor operator mechanism  60  to the circuit breaker  10 . 
     Referring to FIG. 8, a plate  150  is shown. Plate  150  includes a base  152  having a first edge  154 , second edge  156 , third edge  158  and fourth edge  160 . Third edge  158  and fourth edge  160  are positioned between first and second edges  154 ,  156 . Integral with the base  152  are two legs  162 ,  164  projecting outward from the base  152  along second edge  156 . Preferably, the base  152  is angled relative to the legs  162 ,  164  and the legs  162 ,  164  project outward from the base  150  in a side-by-side relation. Preferably, the legs  162 ,  164  are generally adjacent to each other in the same plane and are separated by a cutout  240 . Extending outward from third edge  158  is a projection  166 . Extending outward from fourth edge  160  is a projection  168 . Leg  162  also includes an aperture  170  preferably centrally located. Likewise, leg  164  includes an aperture  172  preferably centrally located. 
     Referring back to FIGS. 4,  5 ,  6  and  7 , the mounting and securement of the motor operator mechanism  60  to the circuit breaker  10  (FIG. 1) will now be described. 
     The plate  150  is securely held between side frames  140 ,  142  of the operating mechanism  38  by inserting the projection  166  of plate  150  within opening  144  of side frame  140  and inserting the projection  168  of plate  150  within opening  146  of the side frame  142 . When the mid cover  24  is then mounted on the base  26  of the circuit breaker  10 , the apertures  130 ,  132  of the base portion  114  align with the apertures  170 ,  172  in the respective legs  162 ,  164  of the plate  150 . 
     The bracket portion  112  is then set in position by inserting the bushings  134 ,  136  through respective apertures  108 ,  110  in the portion  106  of the mid cover  24  in order that the bushings  134 ,  136  align with the apertures  170 ,  172  located within the plate  150 . 
     The mounting base  62  is then positioned on top of the mid cover  24  such that the toggle handle  44  extends through opening  94  and the free ends  128  of legs  124 ,  126  of the bracket portion  112  protrude outward from the cutout portion  104 . In this way, the cutout portion  104 , the apertures  130 ,  132  in the base  114  of the bracket portion  112 , the respective apertures  108 ,  110  in the portion  106  of the mid cover  24  and the respective apertures  170 ,  172  in the plate  150  are all aligned such that respective mechanical fasteners  186 ,  188  can be inserted there through for full thread engagement. 
     Thus, the mechanical fasteners  186 ,  188  position and secure the bracket portion  112  within the mounting base  62  such that the bracket portion  112  is captively held within cut-out portion  104  of the mounting base  62 . Further, mechanical fasteners  186 ,  188  also securely hold the bracket portion  112  to the plate  150  which is connected to the operating mechanism  38 . In this way, the bracket portion  112  is also rigidly and securely connected to the operating mechanism  38 . The mounting base  62  is then secured to the mid cover  24  by mechanical fasteners (not shown), preferably screws. 
     Once the mounting base  62  and bracket portion  112  are secured as described hereinabove, the motor operator mechanism  60  is connected to the mounting base  62 . A rod  88  is inserted through a channel  90  (FIG. 6) formed within the mounting base  62 . The side frames  68 ,  70  of the motor operator mechanism  60  are attached to end  74  of the mounting base  62  by insertion of rod  88  through respective holes  216 ,  220  within mounting base  62  and through apertures  86  located within respective side frames  70 ,  68 . As rod  88  traverses side frame  68  and side frame  70  rocking motion of the motor operator mechanism  60  about rod  88  is permitted. When the motor operator mechanism  60  is in a retracted position, access to openings  96 ,  98  is provided. 
     Next, the side frames  68 ,  70  of the motor operator mechanism  60  are interlocked with the (respective) free ends  128  of the legs  124 ,  126  of the bracket portion  112 . The recess  78  of side frame  68  captures the free end  128  of the leg  126 . Likewise, the recess  206  of side frame  70  captures the free end  128  of the leg  124 . When assembly is complete, as described hereinabove, the motor operator mechanism  60  is securely and accurately connected to the circuit breaker  10  and more particularly, the side frames  68 ,  70  of the motor operator mechanism  60  are securely connected to the respective side frames  140 ,  142  of the operating mechanism  38  ensuring against excessive lost motion between the motor operator mechanism  60  and the toggle handle  44  in a generally longitudinal direction as indicated by arrows on FIG.  3 . Finally, mounting base  62  is attached to the mid cover  24  with mechanical fasteners (not shown) inserted through apertures  190 ,  192  within the mid cover  24 . 
     While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.