Abstract:
The invention relates to a modular disconnect switch ( 10 ) for use in an electrical enclosure cabinet ( 26 ) having a plurality of different operating mechanisms that can be assembled with the switch. These include, but are not limited to: a dial-type ratcheting rotary switch with a door-sensitive actuating mechanism ( 40 ), a dual rotary switch ( 30 ) that meets certain standards and provides a butterfly handle inside the cabinet, a lock accessory ( 60 ) for enabling the lockout of the switch in the off position, a motion translator device ( 50 ) for interfacing to a side-mounted cabinet door handle, a network connectivity module ( 70 ), and a module for adding at least one switch pole to the basic disconnect switch ( 10 ).

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   NOT APPLICABLE 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
   NOT APPLICABLE 
   TECHNICAL FIELD 
   The field of the invention is fused and non-fused disconnect switches of the type used in enclosures for electrical control equipment. 
   BACKGROUND ART 
   In factory automation and other commercial applications requiring control of motors and other electrical equipment, it is typical to mount electrical controls in a cabinet-styled enclosure. A door handle interlock mechanism is provided, so that when the door handle is operated to open the cabinet door and access the electrical control equipment, power is turned off. In particular, power to the other devices in the cabinet is supplied through a fused or non-fused disconnect switch. This switch may have multiple circuits or poles to handle polyphase voltages which may be supplied to the electrical equipment. 
   Once the cabinet has been opened, it may be desirable for service operations to again apply power to the devices in the cabinet. In the past, this was accomplished through certain types of methods for overriding the door interlock switch. 
   New standards have required that an on-off switch be provided in the interior of the cabinet for maintaining a locked-out “off” condition of the disconnect switch when the door of the enclosure is open. The standards also require that the switch be operable by qualified persons, independent of door position, and that in order to be switched to an “on” condition with the door open, the switch should require a deliberate action of the qualified person. The switch should also be capable of compatibility with various door interlock mechanisms available now and in the future. 
   Customers and applications require disconnect switches that can be provided in different configurations (e.g., with different numbers of poles, with front or side-operated switches, with rotary switch handles that are compliant with applicable standards, with or without lockout capability, and with or without network connectivity). 
   Customers prefer those disconnect switches which can be easily and quickly selected and assembled to satisfy their specifications. Such switches provide for high flexibility and a reduction in inventory costs. Network connectivity provides for faster diagnostics and servicing of the equipment at lower cost. 
   SUMMARY OF THE INVENTION 
   The invention relates to a modular disconnect switch for use in electrical enclosure cabinets having a plurality of different operating mechanisms that can be assembled with the switch. 
   These include, but are not limited to: a rotary switch with a door-sensitive coupling mechanism, a rotary switch that inside the cabinet that requires a two-part deliberate action for actuation, a lockout accessory for enabling the lockout of the switch in the off position, a motion translator device for interfacing to a side-mounted cabinet door handle, a network connectivity module, and modules for adding switch poles to the basic disconnect switch. 
   These accessories are made as modules that are interchangeable with other modules in the group through common interfaces. A first interface for various switching accessories is provided by a socket which is part of the mechanism for actuating and de-actuating the switch contacts. A second interface is provided for electrical and mechanical connection to switch modules which can be added to the basic three-pole switch body. 
   It is one object of the invention to provide several types of rotary switches that are installed inside the electrical enclosure to apply or disconnect power. 
   It is another object of the invention to provide a disconnect switch system that can be easily specified in different configurations. 
   It is another object of the invention to provide components that can be easily and quickly assembled to the basic disconnect switch. 
   It is another object of the invention to provide for network connectivity. 
   These and other objects and advantages of the invention will be apparent from the description that follows and from the drawings which illustrate embodiments of the invention, and which are incorporated herein by reference. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective, generalized view of a disconnect switch installed in an electrical enclosure with one of the modular accessories of the present invention; 
       FIG. 2  is an exploded, detail perspective view of the disconnect switch of the present invention; 
       FIG. 3  is a partially exploded perspective view of a network connectivity module included in the disconnect switch of  FIG. 1 ; 
       FIG. 4  is an electrical schematic view of the disconnect switch of  FIG. 3  including the network connectivity module; and 
       FIG. 5  and is a perspective assembly view of a lockout assembly, which is one of the accessories in  FIG. 1 ; and 
       FIG. 6  is an exploded view of the assembly of  FIG. 5 . 
   

   DETAILED DESCRIPTION 
     FIG. 1  illustrates a disconnect switch  10  which is mounted in the interior of an enclosure  26  with other electrical control equipment (not shown), such as relays, contactors and motor starters, to control the connection of electrical power to items inside the enclosure  26 . The cabinet enclosure  26  includes a door  24  mounted by top and bottom hinges  25  to the cabinet body  16 , for opening and closing a frontal access opening into a cabinet body  16 . The disconnect switch  10  receives switch contact cartridges  12 , which can include fuses and which be inserted in a supporting body  11  for the disconnect switch. The electrical power is typically three-phase power and the disconnect switch  10  has at least three fuse cartridges  12   a ,  12   b ,  12   c  ( FIG. 2 ) corresponding to the three switch poles or sub-circuits. The switch  10  is rated for three-phase operation, although single-phase operation is also possible. 
   Electrical power is received through one set of input lines  18  in  FIG. 1  connecting to input terminals along the top of the disconnect switch  10 . From there, power is routed to the fuse cartridges  12   a – 12   c . Output lines  20  ( FIG. 1 ) are connected to output terminals along the bottom of the disconnect switch  10 , to conduct power to the other equipment in the cabinet. 
   A handle  28  on the front of the door  24  in  FIG. 1  is coupled through a shaft  22  to operate the actuating mechanism of the switch  10 . The disconnect switch  10  and its contacts are closed or “ON”, when the door  24  of the enclosure  10  is closed and the handle  28  is in the closed and locked position. When the door handle  28  is moved to a fully “open” position, to open the door  24  of the enclosure, the actuating mechanism in the switch  10  will have been moved to open the contacts, so that power to the cabinet is disconnected. This is a simplified explanation of the operation of the door handle  28 , for the purpose of the present invention. A more complex opening sequence may be employed, but it forms no part of the present invention. 
   Referring to  FIG. 2 , the disconnect switch  10  has an actuating mechanism  80  with three positions, “ON”, “OFF” and “TEST”, as shown by the legends  FIG. 2 . In the “OFF” position, (with the “OFF” legend opposite reference indicator  17 ), the switch contacts in the disconnect switch are open and power is disconnected from the equipment in the cabinet  26 . When the mechanism  80  is rotated ninety degrees clockwise to the “ON” position, (moving the “ON” legend in  FIG. 2  into alignment with the reference indicator  17 ), the rotational action is translated to a rotational member (not shown) extending transversely in relation to the switch cartridges  12   a – 12   c  and when this member is moved, the switch contacts (S 1 –S 6  in  FIG. 4 ) are closed with a snap action. This mechanism  80  is known from prior disconnect switches and is not part of the present invention. 
   The disconnect switch  10  of the present invention is provided in sizes with ratings of sixty (60) amps, thirty (30) amps and smaller. A switch actuating mechanism for this use must be capable of transmitting sufficient torque to open and close the disconnect switch with the snap action typical in such switches. The torque required to actuate and de-actuate a 30-amp disconnect switch is 20 inch-lbs., while the torque required to actuate and de-actuate a 60-amp disconnect switch is 40 inch-lbs. 
   Once the cabinet  26  has been opened ( FIG. 1 ), it may be desirable for service operations to again apply power to the devices in the cabinet  26 . In the past, this was accomplished through certain types of methods for overriding the door interlock handle  28  and interlock shaft  22 . 
   New standards from a U.S. standards organization have required that an on-off switch handle be provided in the interior of the cabinet for maintaining a locked-out and “OFF” condition of the disconnect switch  10  when the door  24  of the enclosure  26  is open. The standard requires that the switch assembly be operable by qualified persons, independent of door position, and that in order for the disconnect switch  10  to be switched to an “ON” condition with the door  24  open, the switch assembly should require a deliberate action of the qualified person. The switch assembly should also be capable of compatibility with various door interlock mechanisms available now and in the future. 
   Referring to  FIG. 2 , a rotary switch assembly  29  can be installed inside an electrical enclosure  26  on a switching interface  81  of an actuating mechanism  80  of the disconnect switch  10  to control actuation and de-actuation of the disconnect switch contacts through a two-part movement, first, in an axial direction, and then, in a rotational direction. 
   The switch assembly  29  includes a butterfly handle  30 , ( FIG. 2 ) which is formed symmetrically along a central rib  31  with two wings extending in opposite axial directions from a central hub  32 . A first grip is formed by a first groove  34  for a thumb along a first side of the rib  31  and grooves for two opposing fingers (like grooves  35 ) along an opposite side of central rib  31  for turning the handle  30  in one direction around its central pivot. The second grip is formed by a groove for a thumb on the opposite side from first groove  34 , and by grooves  35  for two opposing fingers on the first side of the central rib  31  for turning the handle  30  in an opposite rotational direction about its central pivot. Rests  36 ,  37  are formed to extend laterally from the bottom of the rib  31  to support the thumb an forefingers placed in grooves  34 ,  35 . The rotary handle  30  therefore forms a first grip for gripping and rotating the handle  30  in one rotational direction and a second grip formed for gripping and turning the handle  30  in an opposite rotational direction. 
   The handle  30  is installed on a shorter shaft  23  of non-circular cross section that fits through an aperture in hub  32 . The non-circular cross section allows application of torque without the handle  30  slipping on the shaft  22 . The lower end of the shaft  23  is received in the rotor of a switching mechanism  38  that also receives an upper end of the shaft  27 , which is received in an aperture of a switching interface  81  in a main actuating mechanism  80  ( FIG. 2 ) for the disconnect switch  10 . The switching interface  81  includes the aperture and a top surface of a rotatable part of the actuating member  80 . This is called a “split-shaft” arrangement, which allows coupling to the actuating mechanism  80  when the switch assembly  29  is moved to the “ON” position and de-coupling from the disconnect switch actuating mechanism, when the handle  30  is in the “off” position. 
   This switch assembly  29  also provides a mechanism that requires that a person apply a first force axially inward and then a second force in a rotational direction, preferably at least a quarter turn, to move the switch to the “ON” position. This two-step operation requires a deliberate action and avoids inadvertent switch actuations. For a further description of this switch assembly, reference is made to a copending application of Bortolloni et al., entitled “Rotary Service Switch for the Interior of Electrical Enclosures having a Disconnect Switch,” filed on even date herewith, the disclosure of which is incorporated herein by reference. 
     FIG. 2  also shows a view of a second rotary switch assembly  40  which is disclosed in U.S. patent application Ser. No. 10/714,433 filed on Nov. 14, 2003, and entitled “Fuse Block with Door Sensing Rotary Disconnect” The disclosure therein is hereby incorporated by reference. This rotary switch assembly  40  has a dial-type handle provided by a scalloped ring  41  for rotation in either direction and a door-sensitive button  44  which is released by the opening of the enclosure door to prevent the switch from being operated without further operator actions such as, 1) depressing the button  44  or 2) pulling up on the scalloped ring  41 , which has grooves  42  for receiving the fingers of an operator. These actions allow a ratcheting mechanism in the interior of a hub  45  for the switch assembly to couple the rotation of the ring  41  in either direction to the shaft  46 . This shaft  46  is received in opening of the switching interface  81  in the disconnect switch operating mechanism  80 . 
   The button mechanism  44  further includes a keyway  47  that receives a shaft and pin coupling the mechanism to the door handle  28  seen in  FIG. 1 , such that the operating shaft  46  and hub  45  can rotate in concert with the door handle  28  when the door  24  is closed. When the door  24  is opened, the shaft (not shown) is pulled out of the keyway  47  to disconnect the door handle  28  from the rotary switch  40 , with the rotary switch  40  remaining in position to operate the disconnect switch  10 . The button mechanism  44  is spring-loaded and can thus be depressed with respect to hub  45  when door  24  is closed to re-couple the mechanism to door handle  28 . 
   For additional details of construction, reference is made to U.S. patent application Ser. No. 10/714,433 filed on Nov. 14, 2003, and entitled “Fuse Block with Door Sensing Rotary Disconnect,” cited above. 
   It is also possible to provide a rotary switch on a side of the cabinet enclosure  26 . In this configuration, a third switching assembly comprising a motion translator switching assembly  50  on the switching interface  81  for translating a rotary motion from a rotary switch on the side of the cabinet through a horizontal shaft  51  to a depending shaft  52  that couples the assembly  50  to switch actuating mechanism  80 . The motion translator  50  uses gears or other well known mechanical devices for translation motion between two shafts  51 ,  52  having axes of rotation that are orthogonal (ninety degrees apart). 
   Another modular assembly is provided by a lockout assembly  60  that is installable on the switching interface  81  with a holed lockout tab  62  that will receive the shackle  61  of a padlock  63  to lockout the switch actuating mechanism in the “off” position. Screws (not shown) are inserted through mounting bosses  64 ,  65  into bosses  66 ,  67  on the switch body  11  to hold the lockout assembly  60  in place on the actuating mechanism. 
   The details of this assembly  60  are seen in  FIGS. 5 and 6 . A base  69  has a generally central aperture  69   b  for passage of the switch shaft  22 ,  27 ,  46 ,  52 . An aperture  69   a  is provided near the lockout tab  62  for receiving a finger  76   b  which is part of a slider member  76  seen in  FIG. 6 . The slider member  76  has an opening  76   a  with a notch portion for fitting around the square shaft  22 ,  27 ,  46 ,  52  and preventing it from rotating. The notch is in that position when the finger  76   b  is in the position seen in  FIG. 5 . If a lock shackle is placed through the tab  62 , the finger  76   c  and member  76  cannot be moved to release the shaft into the wider part of the opening  76   a . A bottom retaining member  77  has locking tabs  77   a  and  77   b  for reception in openings in the base  69  to hold the three pieces  69 ,  76  and  77  together. The dial operator  68  fits into the opening  69   b  and has a tab  68   a  that engages in square opening in the switch operator  80  in  FIG. 2  and will rotate the switch operating mechanism  80  unless the switch operating shaft switch shaft  22 ,  27 ,  46 ,  52  is locked against movement. The dial  68  has a pointed indicator  68   c  for indicating, which position it is in based on its position corresponding with the legends, “ON,” “OFF,” and “TEST,” seen on the lockout base member  69  in  FIG. 5 . 
   Another possible assembly, which is individually known in the art, an extension shaft  22  for insertion into the opening of the switching interface  81  of actuating mechanism  80  and for coupling to a door-mounted handle  28  for actuating and de-actuating the disconnect switch contacts as shown in  FIG. 1 . 
     FIGS. 2 ,  3  and  4  illustrate a network connectivity module  70  that is attached to the one side of a disconnect switch  10  having three fuse cartridges  12   a ,  12   b  and  12   c  mounted on a switch body  11 . As seen in  FIG. 3 , this module has flexible hooked fingers  71 ,  72  and flexible channel connectors  73 ,  74  for snapping in grooves in the switch body  11  housing supporting switch cartridge  12   c.    
   External electrical connections are provided by three wires  83  that extend through a network port  75  on the module to plugs  86 ,  87  and  88  which are received in sockets  89 ,  90  and  91  on the switch modules  12   a ,  12   b  and  12   c . Another set of three wires  92  extending through a network port on an opposite side of the network connectivity module  70  to connections (not shown) on the top side of the switch  10 . A five-socket network connector  95  plugs into a five-pin connector  96  on the network connectivity module  70 . 
     FIG. 4  shows a schematic of the switch  10  including the network connectivity module  70 . In the switch body  11 , the fuses F 1 –F 3  are connected through switches S 1 –S 6  on either side to power lines L 1 , L 2  and L 3 . The switch actuating mechanism  80  is coupled to the switches Sl–S 6 . Sensing lines  83  and  92  are connected between the switches S 1 –S 6  and the fuses F 1 –F 3  to sense the state of the fused circuits. In a switch without fuses, the lines would sense the on-off state of the circuits controlled by switches S 1 –S 6 . The sensing lines  83  and  92  connect to the network connectivity module  70  through the ports mentioned above. 
   On board the network connectivity module  70 , the lines are then connected to opto-isolator circuits OPTO 1 –OPT 06 , which are then connected to inputs on a logic circuit  97 . This circuit  97  may be a processor-based circuit or non-processor-based logic circuit for converting the status signals from the fuses F 1 –F 3  to data, which can then be transmitted through the network connectivity port  95 ,  96  over a DeviceLogix™ network or other suitable network to report the conducting or non-conducting state of the fuses. The five line port includes two lines for the 24-volt dc power supply, a line for ground and two data lines, DATA (H) and DATA (L). 
   The ability to add this module  70  to the switch  10 , with a form factor similar to the fuse modules  12   a ,  12   b ,  12   c  enhances the functionality and versatility of the modular switch assembly. The network connectivity module  70  has substantially the same form factor as the fuse modules  12   a ,  12   b , and  12   c , the differences being provided by connectors  71 ,  72 ,  73 ,  74  and  96  described above. 
   A switch module can be added with switch contacts for at least one additional switch pole and a fuse, and with the switch module being connected to the switch actuating mechanism for the disconnect switch  10 . The switch module would have a housing with a base and a fuse cover similar to those seen for the network connectivity module  70 . 
   This has been a description of several preferred embodiments of the invention. It will be apparent that various modifications and details can be varied without departing from the scope and spirit of the invention, and these are intended to come within the scope of the following claims.