Abstract:
Switchgear which combines a visible disconnect switch and a circuit breaker or interrupter capable of interrupting fault currents. The switchgear includes a carriage and a switch actuator connected to the carriage for moving the carriage between a switch-closed position and a switch-open position. A circuit breaker module includes circuit breaker contacts, as well as first and second contactor terminals. The circuit breaker module provides selective electrical connection between the contactor terminals depending on the state of the circuit breaker contacts. A fixed disconnect switch contact us attached to or comprises one of the first and second contactor terminals, and a movable disconnect switch contact is mounted to the carriage so as to move with the carriage. The fixed disconnect switch contact and the movable disconnect switch contact are positioned for selective engagement with each other as the carriage moves to the switch-closed position.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The benefit of U.S. provisional patent application Ser. No. 61/682,489 filed Aug. 13, 2012 is claimed, the entire disclosure of which is hereby expressly incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates generally to electrical switchgear, such as electrical feeder circuit protectors including an electrical contactor, and, more particularly, to switchgear which combines a visible disconnect switch (typically but not necessarily manually-operated) and a circuit breaker (which may also be termed an interrupter) capable of interrupting fault currents. 
     SUMMARY OF THE INVENTION 
     In one aspect, switchgear is provided which includes a carriage and a switch actuator connected to the carriage for moving the carriage between a switch-closed position and a switch-open position. A circuit breaker module includes circuit breaker contacts, as well as first and second contactor terminals. The circuit breaker module provides selective electrical connection between the contactor terminals depending on the state of the circuit breaker contacts. A fixed disconnect switch contact is attached to or comprises one of the first and second contactor terminals, and a movable disconnect switch contact is mounted to the carriage so as to move with the carriage. The fixed disconnect switch contact and the movable disconnect switch contact are positioned for selective engagement with each other as the carriage moves to the switch-closed position. 
     In another aspect, switchgear is provided which includes a carriage and a switch actuator connected to the carriage for moving the carriage between a switch-closed position and a switch-open position. A circuit breaker module includes circuit breaker contacts which are opened and closed by an electrically-activated magnetic actuator. The circuit breaker module includes first and second contactor terminals and provides selective electrical connection between the contactor terminals depending on the state of the circuit breaker contacts. The magnetic actuator is stable in either a breaker-closed state or a breaker-open state without requiring electrical current flow through the magnetic actuator. The circuit breaker module also includes an externally-connectable mechanical drive linked to the magnetic actuator in a manner such that movement of the externally-connectable mechanical drive can destabilize the breaker-closed state to open the circuit breaker contacts. The circuit breaker module includes an insulating tower generally cylindrical in configuration defining a longitudinal axis, and having a top. A fixed disconnect switch contact is attached to or is one of the first and second contactor terminals, the one of the first and second contactor terminals being located at the top of the tower; and a movable disconnect switch contact is mounted to the carriage so as to move with the carriage. Another of the first and second contactor terminals is located on a cylindrical side of the tower. The fixed disconnect switch contact and the movable disconnect switch contact are positioned for selective engagement with each other as the carriage moves to the switch-closed position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a three-dimensional view of an “LD Series” circuit breaker manufactured by Tavrida Electric; 
         FIG. 1B  is an end elevational view of the circuit breaker of  FIG. 1A ; 
         FIG. 1C  is a three-dimensional underside view of a portion of the circuit breaker of  FIG. 1A ; 
         FIG. 1D  is a partially exploded three-dimensional view corresponding to the view of  FIG. 1C ; 
         FIG. 2  is a right side three-dimensional view of switchgear embodying the invention in a first configuration or state, wherein the disconnect switch and interrupter are both open; 
         FIG. 3  is a right side elevational view of the switchgear embodying the invention in its first configuration or state; 
         FIG. 4  is a three-dimensional view generally from the front of the switchgear embodying the invention in its first configuration or state; 
         FIG. 5  is a front elevational view of the switchgear embodying the invention in its first configuration or state; 
         FIG. 6  is a rear elevational view of the switchgear embodying the invention in its first configuration or state; 
         FIG. 7  is a three-dimensional view generally from the left side of the switchgear embodying the invention in its first configuration or state; 
         FIG. 8  is an elevational view from the left side of the switchgear embodying the invention in its first configuration or state; 
         FIG. 9  is a right side elevational view of the switchgear embodying the invention, in the same orientation as  FIG. 3 , but in a second configuration or state wherein the disconnect switch and the interrupter are both closed; 
         FIG. 10  is a front elevational view, in the same orientation as  FIG. 6 , but with the switchgear embodying the invention in its second configuration or state; 
         FIG. 11  is a rear elevational view, in the same orientation as  FIG. 6 , of the switchgear embodying the invention in the second configuration or state; 
         FIG. 12  is a left side elevational view of the switchgear embodying the invention, in the same orientation as  FIG. 8 , but in the second configuration or state; 
         FIG. 13  is a right side elevational view of the switchgear embodying the invention, in the same orientation as  FIGS. 3 and 9 , but in a third configuration or state wherein the disconnect switch is closed, but the interrupter is open; 
         FIG. 14  is a left side elevational view of the switchgear embodying the invention, in the same orientation as  FIGS. 8 and 12 , but with the switchgear in the third configuration or state; 
         FIG. 15  is a right side elevational view of the switchgear embodying the invention, in the same orientation as  FIGS. 3 ,  9  and  13 , but with the switchgear in an intermediate transitory configuration or state; and 
         FIG. 16  is a left side elevational view of the switchgear embodying the invention, in the same orientation as  FIGS. 8 ,  12  and  14 , but with the switchgear in the intermediate transitory configuration or state. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1A ,  1 B,  1 C and  1 D illustrate a circuit breaker module  20  having particular characteristics, described hereinbelow, which are utilized in embodiments of the subject invention. (Depending on the context, a circuit breaker may also be termed an interrupter. For purposes of this disclosure, the two terms have the same meaning.) 
     By way of example and not limitation, the particular circuit breaker module  20  illustrated in  FIGS. 1A-1D  is an “LD Series” circuit breaker module manufactured by Tavrida Electric, and available through their North American office located on Annacis Island, Delta, British Columbia, Canada, internet website tavrida-na.com. “LD Series” circuit breaker modules are available in 5 kV, 15 kV, and 27 kV sizes. The circuit breaker module  20  is similar to, and employs the same principles as a circuit breaker module disclosed in international patent application Publication No. WO 2004/086437 A1, titled “Vacuum Circuit Breaker,” and naming as applicant Tavrida Electrical Industrial Group, Moscow, Russia, the entire disclosure of which is hereby expressly incorporated by reference. A typical installation includes a control module  22  (represented in  FIGS. 11 and 12 ) which generates current pulses to provide close and open (trip) functionality. However, a characteristic of the circuit breaker module  20  is that it is stable in either a breaker-closed state or a breaker-open state without requiring continuous electrical energization, such as from the control module  22 . (An example of a control module is a Tavrida Electric model CM-15-1 electronic control module.) 
     The circuit breaker module  20  includes a base  24  which serves as a lower housing or enclosure for various components, and three individual phase modules  26 ,  28  and  30  partially secured within and extending upwardly from the base  24 . Although a three-phase circuit breaker module  20  is illustrated, and embodiments of the invention illustrated and described herein employ a three-phase circuit breaker module, such is by way of example and not limitation. The invention may, for example, be embodied in single-phase switchgear employing a single-phase circuit breaker. 
     The three-phase modules  26 ,  28  and  30  are essentially identical. Accordingly, only phase module  26  is described in detail hereinbelow, as representative. 
     The phase module  26  includes an outer insulating tower  32 , and a vacuum circuit breaker, generally designated  34 , within an upper portion of the insulating tower  32 . The vacuum circuit breaker  34  more particularly includes a fixed upper circuit breaker contact  36  and a movable lower circuit breaker contact  38  which open and close during operation. In the configuration of  FIG. 1A , the circuit breaker contacts  36  and  38  are open, separated by a gap of approximately three-eighths inch (1 cm). The circuit breaker contacts  36  and  38  are within a vacuum chamber  40  defined in part by a generally cylindrical ceramic body  42 . 
     The fixed upper circuit breaker contact  36  is electrically connected to an upper terminal structure  44  which passes through a seal  46  at the top of the vacuum chamber  40 , terminating in an upper screw terminal  48  at the top of the outer insulating tower  32 . 
     The movable lower circuit breaker contact  38  is mechanically and electrically connected to a conductive rod  50  which exits the bottom of the vacuum chamber  40 , sealed by a bellows-like flexible diaphragm  52  so that the conductive rod  50  can translate up and down. The diaphragm  52  is annularly sealed at its upper end  54  to the ceramic body  42  of the vacuum chamber  40 , and annularly sealed at its lower end  56  to the conductive rod  50 . Accordingly, the conductive rod  50  and thus the movable lower circuit breaker contact  38  can move up and down to close and open the circuit breaker contacts  36  and  38 , while maintaining vacuum within the vacuum chamber  40 . 
     The conductive rod  50  is electrically connected to a side terminal  60  of the phase module  26  via a flexible junction shunt  62 . Thus, the upper screw terminal  48  and the side terminal  60  serve as external high voltage terminals of the phase module  26 . 
     Also visible in  FIGS. 1A and 1B  is a general purpose insulated mount  64  secured to the outside of the outer insulating tower  32 , and electrically insulated from the internal high voltage components. As an example, the insulated mount  64  may be employed to mechanically secure conventional barriers (not shown) between the phase modules  26  and  28 , and between the phase modules  28  and  30 . 
     Generally within the base  24 , the circuit breaker module  20  includes an electrically-activated magnetic actuator  70  connected via a drive insulator  72  to drive the conductive rod  50  for closing and opening the circuit breaker contacts  36  and  38 . 
     As described in greater detail hereinbelow, the magnetic actuator  70  is stable, without requiring electric current flow through the magnetic actuator  70 , either in a breaker-closed state (in which the conductive rod  50  and movable lower circuit breaker contact  38  are driven upward), or in a breaker-open state (the configuration of  FIG. 1A ) in which the conductive rod  50  and the movable lower circuit breaker contact  38  are retracted downwardly. 
     The magnetic actuator  70  includes, near the upper end of the magnetic actuator  70 , an annular magnetic stator  74 ; near the lower end of the magnetic actuator  70 , a movable annular magnetic armature  76  which moves relative to the stator  74 ; and a coil  78  which is energized with electrical current to activate the magnetic actuator  70 . The magnetic actuator  70  additionally includes a compression spring  80  mechanically connected so as to urge the armature  76  down and away from the magnetic stator  74 . 
     An actuator rod  82  is connected to be driven by the magnetic armature  76  and passes upwardly through a central passageway in the magnetic actuator  70 . At its upper end the actuator rod  82  is connected to the lower end of the drive insulator  72 . 
     Accordingly, when an energizing current is driven through the coil  78  in a manner directing the breaker contacts  36  and  38  to close, the magnetic armature  76  moves upwardly to physically contact the magnetic stator  74 , driving the actuator rod  82 , drive insulator  72 , conductive rod  50  and movable lower circuit breaker contact  38  upwardly. When current is driven through the coil  78  in a manner directing the circuit breaker contacts  36  and  38  to open, the magnetic armature  76 , urged by the compression spring  80 , moves downwardly, away from the magnetic stator  74 , pulling down on the drive insulator  72 , and thus the conductive rod  50  and lower circuit breaker contact  38 . 
     An important characteristic of the magnetic actuator  70  is that a portion of the magnetic stator  74  is made of high-coercivity material. In other words, and stated more generally, during operation, at least one of the magnetic stator  74  and the magnetic armature  76  has characteristics of a permanent magnet, maintaining residual magnetism, such that, in the breaker-closed state, the stator  74  and armature  76  are magnetically held tightly together, against the force of the compression spring  80 , and without requiring any ongoing energization of the coil  78  to hold or maintain the closed state. Accordingly, the armature  76  is magnetically latched to the stator  74 , holding the circuit breaker contacts  36  and  38  closed. 
     During operation, the control module  22  drives current through the coil  78  so as to close and open the circuit breaker contacts  36  and  38 . More particularly, to close the circuit breaker contacts  36  and  38 , the control module  22  drives a current pulse of one polarity through the coil  78 , causing the magnetic armature  76  to move upward against the stator  74 , to be held by residual magnetism. When the circuit breaker contacts  36  and  38  are to open (trip), the control module  22  drives a current pulse of opposite polarity through the coil  78 , which demagnetizes the stator  74  and armature  76 , so that the armature  76  moves downward and away from the stator  74 , urged by the compression spring  80 . 
     Thus, fundamentally the magnetic actuator  70  and therefore the phase module  26  are electrically-activated by current pulses from the control module  22  to either close or open (trip) the circuit breaker contacts  36  and  38 . However, the circuit breaker contacts  36  and  38  also can be mechanically opened, without requiring a current pulse through the coil  78 . 
     More particularly, an externally-connectable mechanical drive, generally designated  84 , is provided. The externally-connectable mechanical drive  84  can destabilize the breaker-closed state to open the circuit breaker contacts  36  and  38 . The residual magnetic characteristics of the stator  74  and armature  76  are such that the stator  74  and armature  76  are held tightly together so long as there is no gap in between them. With sufficient external force, the armature  76  can be pulled down away from the stator  74 , breaking the magnetic latch. 
     In the particular embodiment described in detail herein, the externally-connectable mechanical drive  84  takes the form of a shaft  90 , which in a three-phase breaker also functions as and may be termed a synchronizing shaft  90 , which engages a mechanical coupling structure  92  (detailed in  FIGS. 1C and 1D ) secured to the underside of the movable armature  76 , as part of a mechanism to convert linear up and down motion of the armature  76  to rotational motion of the synchronizing shaft  90 , and vice versa. The mechanical coupling structure  92 , which functions as a notched rod, cooperates with a slotted tooth  94  fixed to the shaft  90  or synchronizing shaft  90 . The slotted tooth  94 , which resembles a cam, has a plurality of individual tooth sections  96  which engage corresponding openings  98  in the mechanical coupling structure  92 , the openings  98  being separated by ribs  100 . Accordingly, external rotation of the synchronizing shaft  90  (counterclockwise in the orientation of  FIGS. 1A ,  1 B,  1 C and  1 D), and thus of the slotted tooth  94 , pulls the coupling structure  92  downward, and the magnetic armature  76  away from the stator  74 , thereby breaking the magnetic latching effect, destabilizing the breaker-closed state, so that the circuit breaker contacts  36  and  38  open. 
     Conversely, during normal operation of the circuit breaker module  20 , when the coil  78  is driven by the control module  22 , up and down motion of the magnetic armature  76  is transmitted via the coupling structure  92  and the slotted tooth  94  to rotate the synchronizing shaft (or, more generally, to move the externally-connectable mechanical drive  84 ) in one direction or another between a breaker-closed and a breaker-open position as the magnetic actuator  70  opens and closes the circuit breaker contacts  36  and  38 . This movement of the externally-connectable mechanical drive  84  (rotation of the synchronizing shaft  90  in the disclosed embodiment) can be employed to mechanically drive external elements, for example, for the purpose of indicating the state of the circuit breaker module  20 , in other words, whether the contacts  36  and  38  are open or closed. In addition, in order to mechanically and positively prevent closure of the circuit breaker contacts  36  and  38  notwithstanding energization of the coil  78 , movement of the mechanical drive  84  can externally be blocked. In the illustrated embodiment, an end  104  of the synchronizing shaft  90  has a slot  106  extending diametrically across the end  104  to facilitate positive mechanical engagement with the synchronizing shaft  90 . 
     In the illustrated embodiment where there are three-phase modules  26 ,  28  and  30 , another one of the functions of the synchronizing shaft  90  is to ensure that the circuit breaker contacts of all three-phase modules  26 ,  28  and  30  open and close together. For this purpose, external mechanical connections to the synchronizing shaft  90 , either to drive the synchronizing shaft  90  or to be driven by the synchronizing shaft  90 , are not relevant. 
     Alternatively, the externally-connectable mechanical drive  84  may take the form of a push pin  108  or interlocking pin  108  which is part of the circuit breaker module  20 , and is linked to the synchronizing shaft  90 . (Two push pins or interlocking pins are provided, but they are essentially identical, and only push pin  108  is described in detail herein.) To convert rotational motion to the synchronizing shaft  90  to linear in-and-out motion of the push pin  108 , a radially-extending pin  110  is fixed to the synchronizing shaft  90 , and the pin  110  engages an aperture  112  in the push pin  108 . The aperture  112  is slightly elongated. 
     Accordingly, externally pushing in the push pin  108  causes the synchronizing shaft  90  to rotate, in turn pulling the magnetic armature  76  down away from the stator  74  to open the circuit breaker contacts  36  and  38 . Conversely, during normal operation of the circuit breaker module  20 , up and down motion of the armature  76  as the coil  78  is energized is converted to rotation of the synchronizing shaft  90 , which drives out and in motion of the push pin  108 . Although not illustrated, external mechanical connections, described in greater detail hereinbelow, may be made to the push pin  108  rather than to the end  104  of the synchronizing shaft  90 . 
     Referring now to  FIGS. 2-8 , switchgear  120  embodying the invention is shown in a first configuration or state. 
     The switchgear  120  includes a visible disconnect switch, generally designated  122 , as well as the circuit breaker or interrupter module  20  which includes the actual vacuum interrupter  34 . The circuit breaker or interrupter module  20  and visible disconnect switch  122  are mounted to a fixed frame  124 . 
     The circuit breaker or interrupter module  20  included as part of the switchgear  120  is as described hereinabove with reference to  FIGS. 1A ,  1 B,  1 C and  1 D. 
     The insulating towers  32  of the circuit breaker or interrupter module  20  are generally cylindrical in configuration, defining respective longitudinal axes  126 ,  128  and  130 , and each has a top defined by the upper terminal structure  44 . The longitudinal axes  126 ,  128  and  130  are parallel to each other and in a common plane. Attached and electrically connected to each upper terminal structure  44  is a fixed disconnect switch contact  132 ,  134  or  136 . 
     As part of the visible disconnect switch  122 , the switchgear  120  includes a carriage  140 , which can move or translate up and down in the orientation of the drawing FIGURES on linear bearings  142  ( FIGS. 4 and 7 ) along cylindrical rails  144  supported by mounts  146  secured to the frame  124 . To facilitate “over center” locking in the switch-open and switch-closed positions as described in greater detail hereinbelow, upper compression springs  148  and lower compression springs  150  are located immediately adjacent the mounts  146 , and are engaged by the linear bearings  142  at the upper and lower limits of carriage  140  travel. More particularly, the carriage  140  can move or translate in a direction parallel to the longitudinal axes  126 ,  128  and  130  of the insulating towers  32 , and parallel to the plane in which the axes  126 ,  128  and  130  lie. In addition to the linear bearings  142 , the carriage  140  includes a base plate  152  to which the linear bearings  142  are secured, and in essence the carriage  140  is supported by the linear bearings  142 . 
     Secured to the carriage  140  are three insulators  160 ,  162  and  164  having respective distal ends  166 ,  168 , and  170 . Attached to and supported by the distal ends  166 ,  168  and  170  are respective terminal/contact structures  172 ,  174  and  176 , each comprising a movable disconnect switch contact  178 ,  180  or  182 , and a terminal  184 ,  186  or  188 . The terminals  184 ,  186  and  188  serve as either input or output terminals of the switchgear  120  depending on the particular application. Correspondingly, the side terminals  60  of the phase modules  26 ,  28  and  30  serve as either output or input terminals of the switchgear  120 , again depending on the particular application. Flexible power conductors (not shown) are connected to the terminals  184 ,  186  and  188 , respectively. The flexible power conductors may be connected either to a power source, or to a load. 
     The fixed disconnect switch contacts  132 ,  134  and  136  and the movable disconnect switch contacts  178 ,  180  and  182  are significant elements of the visible disconnect switch  122 . Significantly, the open ( FIGS. 2-8 ) or closed ( FIGS. 9-12  and  FIGS. 13 and 14 ) configuration or state of the visible disconnect switch  122 , and more particularly the configuration or state (whether opened or closed) of the contact pairs  132 ,  178 ;  134 ,  180 ; and  136 ,  182 , is readily observable. 
     In the first configuration or state of the switchgear  120  as illustrated in  FIGS. 2-8 , the visible disconnect switch  122  and the circuit breaker or interrupter module  20  are both open. The open state of the visible disconnect switch  122  is clearly evident by observing the contact pairs  132 ,  178 ;  134 ,  180 ; and  136 ,  182 . Although internal components of the circuit breaker phase modules  26 ,  28  and  30  are not visible, the open state of the circuit breaker module  20  can be determined by the rotational position of the end  104  of the synchronizing shaft  90 . More particularly, the rotational position of the synchronizing shaft  90  is indicated by the position of a synchronizing shaft lever arm  280  ( FIGS. 2 and 3 ) fixedly connected to the end  105  of the synchronizing shaft, employing the slot  106  for positive location. 
       FIGS. 9-12  correspondingly illustrate the switchgear  120  in a second configuration or state, in which the disconnect switch  122  and the circuit breaker or interrupter module  20  are both closed. The closed state of the visible disconnect switch  122  is clearly evident by observing the contact pairs  132 ,  178 ;  134 ,  180 ; and  136 ,  182 . Again, although internal components of the circuit breaker phase modules  26 ,  28  and  30  are not visible, the closed state of the circuit breaker or interrupter module  20  can be determined by the rotational position of the synchronizing shaft  90 , and more particularly by the position of the synchronizing shaft lever arm  280  ( FIG. 9 ). 
       FIGS. 13 and 14  illustrate the switchgear  120  in a third configuration or state, in which the disconnect switch  122  is closed, but the circuit breaker or interrupter module  20  is open, awaiting activation of the magnetic actuator  70 . This configuration or state is recognized by the closed state of the contact pairs  132 ,  178 ;  134 ,  180 ; and  136 ,  182  of the visible disconnect switch  122  (as in the second state of  FIGS. 9-12 ), and the position of the synchronizing shaft  90  of the circuit breaker module  20  (as in the first state of  FIGS. 2-8 ), and more particularly by the position of the synchronizing shaft lever arm  280  ( FIG. 13 ). 
       FIGS. 15 and 16  illustrates the switchgear  120  in an intermediate transitory state or configuration, between the second configuration or state of  FIGS. 9-12  or the third configuration or state of  FIGS. 13 and 14 , and the first configuration or state of  FIGS. 2-8 , as the visible disconnect switch  122  is either being opened (second state or third state to first state) or closed (first state to third state). 
     During typical operation, during which a load (not shown) is energized and de-energized through operation of the circuit breaker module  20 , the switchgear  120  is in the second configuration or state of  FIGS. 9-12 , or the third configuration or state of  FIGS. 13 and 14 . Thus, typically the visible disconnect switch  122  remains closed, while the circuit breaker module  20  controls energization of the load. 
     For moving the carriage  140  between its disconnect switch  122  open position (the first state or configuration of  FIGS. 2-8 ) and its disconnect switch  122  closed position (both the second state or configuration of  FIGS. 9-12 , and the third state or configuration of  FIGS. 13 and 14 ), and thereby operating the visible disconnect switch  122 , a switch actuator, generally designated  190  is provided. In the illustrated embodiment, the switch actuator  190  takes the form of a pair of push rods  192  and  194  or links  192  and  194 . 
     For operating the switch actuator  190 , a main switch actuator  200  is in turn provided. In the illustrated embodiment, the main switch actuator  200  includes a main actuator shaft  202 . The main actuator shaft  202  is rotatable through an angular range of approximately 240° between a switch-open position (first configuration or state of  FIGS. 2-8 ); and a switch-closed position (second configuration or state of  FIGS. 9-12  and third configuration or state of  FIGS. 13 and 14 ). In the illustrated embodiment, the main actuator shaft  202  and thus the visible disconnect switch  122  is manually-operated by a handle  204 . The handle  204  is exemplary only. Other mechanisms (not shown) may be employed to rotate the main actuator shaft  202  and accordingly operate the visible disconnect switch  122 . For example, a motor (not shown) may be employed. 
     At their lower ends, the push rods  192  and  194  are connected to and moved by corresponding yoke arms  210  and  212  welded to and extending from respective cylindrical yoke hubs  214  and  216 , which hubs  214  and  216  are in turn keyed to the main actuator shaft  202 . 
     In order for the switch-open ( FIGS. 2-8 ); and switch-closed ( FIGS. 9-12 ) and ( FIGS. 13 and 14 ) positions to be locked “over center,” as noted above the handle  204  and main actuator shaft  202  rotate through an angular range of approximately 240° rather than merely 180°. The upper compression springs  148  and the lower compression springs  150  selectively are compressed as the handle  204  and main actuator shaft  202  reach either limit of their rotation. In the switch-closed position, the pushrods  192  and  194  nest onto the yoke hubs  214  and  214 , and are inclined to stay there because the lower compression springs  150  are compressed. Similarly, in the switch-open position, the yoke arms  210  and  212  are rotated upwardly slightly over center, and the upper compression springs  148  are compressed. The shaft  202  and yoke arms  210  and  212  again are inclined to stay in that position. In addition, when moving to either the switch-open or switch-closed position, friction of the linear bearing  142  encourages a slow and deliberate movement between positions. 
     A mechanical interlock, generally designated  240 , is provided, interconnecting the circuit breaker module  20  and the visible disconnect switch  122 . In addition, an electrical interlock (not shown) may be provided. Among other functions, the mechanical  240  and electrical interlocks ensure that switching under load, in particular current interruption, is always provided by the circuit breaker or interrupter module  20 , and never by the contacts  132 ,  178 ;  134 ,  180 ; and  136 ,  182  of the visible disconnect switch  122 . 
     The mechanical interlock  240  more particularly takes the form of a mechanism  240  driven by the main actuator shaft  202 , and, among other aspects, is connected so as to force movement of the externally-connectable mechanical drive  84  of the circuit breaker module  20  so as to cause the circuit breaker contacts, for example the contacts  36  and  38 , to open as the main switch actuator  200  begins to move from its switch-closed position ( FIGS. 9-12 ), which is the second configuration or state, to its switch-open position ( FIGS. 2-8 ), which is the first configuration or state. 
     The mechanical interlock mechanism  240  includes a trip lever assembly  250  including a bearing-supported hub  252  freely rotatable on a bearing  254 , and a trip lever  256  extending radially from the bearing-supported hub  252 . A linkage, generally designated  258 , transfers rotation of the bearing-supported hub  252  to rotation of the synchronizing shaft  90  of the circuit breaker module  20 , and vice versa. The linkage  258  more particularly includes an adjustable-length connecting link  260  having first and second ends  262  and  264 , with a respective clevis  266  and  268  at each end. Also fixably attached to the bearing-supported hub  252  is a connecting lever arm  270 , connected near its distal end  272  to the clevis  268  at the second end  264  of the connecting link  260 . 
     The clevis  266  at the first end  262  of the connecting link  260  is pivotably connected to a synchronizing shaft lever arm  280  fixedly connected to the end  104  of the synchronizing shaft  90 , and keyed employing the slot  106  for positive location. 
     A tripping and mechanical interlock assembly, generally designated  300 , is driven by the main actuator shaft  202  and engages the trip lever assembly  250 , and in particular the trip lever  256  thereof. The tripping and mechanical interlock assembly  300  includes a pair of hub-like bases  302  and  304  secured to an end of the main actuator shaft  202  (opposite the end of the main actuator shaft  202  to which the handle  204  may be connected). Extending generally in diametrically opposite directions are a radially-extending yoke  306  fixed to the hub-like base  302 , and a radially-extending stop arm  308  fixed to the hub-like base  304 . A roller  310  is supported on a bearing at the end of the yoke  306 , and a mechanical stop  312  is at the end of the radially-extending stop arm  308 . 
     In the first configuration or state of the switchgear  120  as illustrated in  FIGS. 2-8 , the handle  204  is rotated clockwise to the rear when viewed from the right side as in  FIGS. 7 and 8 , thus rotating the main actuator shaft  202 . The push rods  192  and  194  are driven upwardly by the yoke arms  210  and  212 , accordingly moving the carriage  140  to its fully upward position, and opening the visible disconnect switch  122  with the contact pairs  132 ,  178 ;  134 ,  180 ; and  136 ,  182  clearly open. The radially-extending stop arm  308  is rotated to a down position. More particularly, the stop  312  is immediately adjacent the trip lever  256  of the trip lever assembly  250 , providing a positive mechanical interlock against attempted closing of the circuit breaker or interrupter module  20 . Although electrical interlocks should prevent any such attempted actuation when the visible disconnect switch  122  is open, even if the magnetic actuator  70  were energized in an attempt to close the circuit breaker or interrupter module  20 , rotation of the synchronizing shaft  90  would positively be prevented by the linkage  258  connected to the lever arm  270 . 
     In the second configuration or state illustrated in  FIGS. 9-12 , the handle  204  is rotated counterclockwise approximately 240° with reference to the first configuration or state, to an upward front position when viewed from the right side as in  FIG. 12 , thus rotating the main actuator shaft  202 . The yoke arms  210  and  212  are directed downwardly, moving the push rods  192  and  194  and the carriage  140  to their full down positions. The visible disconnect switch  122  is closed, as is visibly observable from the mating contact pairs  132 ,  178 ;  134 ,  180 ; and  136 ,  182 . The radially-extending stop arm  308  is rotated upwardly so that the stop  312  is out of the way. At the same time, the radially-extending yoke  306  and roller  310  are rotated to a generally down position. The circuit breaker or interrupter module  20  is closed, with the connecting lever arm  270  moved approximately 45° clockwise with reference to the first configuration or state, and the bearing-supported hub  252  and attached trip lever  256  rotated approximately 45° counterclockwise so that the trip lever  256  rests either in contact with or immediately adjacent the roller  310  of the tripping and mechanical interlock assembly  300 . 
     With the visible disconnect switch  122  closed and the radially-extending yoke  306  and roller  310  of the tripping and mechanical interlock assembly  300  oriented generally downwardly as in the second configuration or state of  FIGS. 9-12 , and in the third configuration or state as in  FIGS. 13 and 14 , the circuit breaker module  20  is free to operate, as directed by energization of the electrically-activated magnetic actuator  70 , between the breaker-closed state of the second configuration or state ( FIGS. 9-12 ) and the breaker-open state of the third configuration or state ( FIGS. 13 and 14 ), without interference by the tripping and mechanical interlock assembly  300 . 
     From either the second configuration or state of  FIGS. 9-12  or the third configuration or state of  FIGS. 13 and 14 , in both cases where the visible disconnect switch  122  is closed, the visible disconnect switch  122  may be opened by operating the main switch actuator  200  via the handle  204 .  FIGS. 15 and 16  illustrate an intermediate or transitory state of such opening, where the main actuator shaft  202  has rotated approximately halfway through its range of rotation. 
     In the event the starting point is the third configuration or state of  FIGS. 13 and 14  where the circuit breaker  20  is already open, and no part of the tripping and mechanical interlock assembly  300  is engaging the trip lever  256 , the visible disconnect switch  122  simply opens. 
     In the event the starting point is the second configuration or state of  FIGS. 9-12  where the circuit breaker module  20  is closed, then initial movement of the main switch actuator  200 , in particular initial rotation of the main actuator shaft  202 , causes the roller  310  at the end of the radially-extending yoke  306  of the tripping and mechanical interlock assembly  300  to force the trip lever assembly  250  into clockwise rotation, and, via the linkage  258 , the synchronizing shaft lever arm  280  connected to the synchronizing shaft  90  of the circuit breaker or interrupter module  20  in a counterclockwise direction, mechanically forcing the vacuum circuit breaker or interrupter  34  of the circuit breaker or interrupter module  20  to open, prior to opening of the contact pairs  132 ,  178 ;  134 ,  180 ; and  136 ;  182  of the visible disconnect switch  122 . In either case, rotation of the main actuator shaft  202  continues until the first configuration or state of  FIGS. 2-8  is reached. 
     Alternatively, the transitory configuration or state of  FIGS. 15 and 16  may be viewed as movement from the first configuration or state of  FIGS. 2-8  where both the circuit breaker or interrupter module  20  and the visible disconnect switch  122  are open and the third configuration or state of  FIGS. 13 and 14  where the circuit breaker or interrupter module  20  is open but the visible disconnect switch  122  is closed. As the main actuator shaft  202  rotates clockwise in the orientation of  FIGS. 15 and 16 , the roller  310  at the end of the radially-extending yoke  306  of the tripping and mechanical interlock assembly  300  clears the trip lever  256 , until reaching the position of  FIGS. 13 and 14 . 
     Finally, to allow remote tripping of the circuit breaker module  20  when in the second configuration or state of  FIGS. 9-12 , on the left side of the switchgear  120  is an actuator arm  350  connected to the end of the synchronizing shaft  90  of the circuit breaker module opposite the synchronizing shaft lever arm  280 . As illustrated in  FIG. 12 , in the second configuration or state when the circuit breaker  20  is closed, the actuator  350  is vertical. In either the first configuration or state of  FIG. 8  or the third configuration or state of  FIG. 14 , the actuator arm  350  is rotated clockwise, when viewed from the left side orientation of  FIGS. 8 and 9 . As is described in greater detail in patent application Ser. No. 13/355,906, filed Jan. 23, 2012, the entire disclosure of which is hereby expressly incorporated by reference, an actuator  352  having an output rod  354  is positioned so as to remotely open the circuit breaker module  20  by causing the actuator arm  350  to rotate clockwise from its  FIG. 12  vertical position. Preferably, the actuator  352  is a magnetically-latched actuator wherein the output rod  354  is movable between a reset retracted position as illustrated and magnetically held against the force of a compression spring  356 , and a triggered extended position (not shown). 
     While a specific embodiment of the invention has been illustrated and described herein, it is realized that numerous modifications and changes will occur to those skilled in the art. It is therefore to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit and scope of the invention.