Motor control center units with retractable stabs and interlocks using portal shutters
AssigneeEaton Corporation
InventorsStephen William Oneufer, Robert Allan Morris, Daniel Boyd Kroushl
Life of this patent
Estimating the term…
Abstract
Motor control centers have units or buckets with one or more sliding shutters that controllably block access to a stab isolation port based on position of the operator disconnect handle using attached cams that slide the shutter right and left. A front panel of the unit or bucket may also be configured to pivot out about a long axis associated with a bottom long side thereof.
Claims24
A bucket sub-assembly to control access to a stab isolation portal of a bucket unit, comprising:
- first and second spaced apart operator disconnect handles, the first operator disconnect handle attached to a first inwardly extending shaft that holds a first cam, the second operator disconnect handle attached to a second inwardly extending shaft that holds a second cam, wherein the first and second cams are configured to independently rotate, and wherein the first cam rotates in response to a rotation of the first operator disconnect handle and the second cam in response to a rotation of the second operator disconnect handle;
- and
- at least one shutter in communication with the first and second cams, wherein the at least one shutter has a shutter portal, and wherein the at least one shutter is configured to cooperate with the first and second cams to laterally slide to a position that misaligns the shutter portal with the stab isolation portal to block access to the stab isolation portal when at least one of the first or the second operator disconnect handles is in an ON position associated with a conduction of electric current through at least one stab of the bucket unit.
A bucket assembly, comprising:
- a unit housing having a front panel and opposing laterally spaced apart right and left sidewalls that extend rearward of the front panel of the unit housing;
- a right operator disconnect handle on a front of the unit housing and attached to a right inwardly extending shaft, wherein the right shaft holds a right cam configured to rotate in response to rotation of the right operator disconnect handle;
- a left operator disconnect handle on the front of the unit housing and attached to a left inwardly extending shaft and being laterally spaced apart from the right operator disconnect handle, wherein the left shaft holds a left cam configured to rotate in response to rotation of the left operator disconnect handle;
- at least one shutter in communication with at least one of the right or the left cam whereby the at least one shutter slides right and left in response to contact with at least one of the right or the left cam;
- and
- a stab isolation portal residing above the right and left shafts of the right and left operator disconnect handles, wherein the at least one shutter has a shutter portal, and wherein the at least one shutter is configured to have a position that misaligns the shutter portal with the stab isolation portal to block access to the stab isolation portal when either of the right and left operator disconnect handles is in an ON position associated with a conduction of electric current through at least one stab of the bucket assembly.
A motor control center (MCC), comprising:
- a cabinet with first and second sidewalls defining an enclosure with a plurality of compartments, the compartments configured to removably receive a plurality of units, wherein at least one of the units comprises:
- a unit housing having a front and opposing laterally spaced apart sidewalls that extend rearward of the front of the unit housing;
- at least one operator disconnect handle on the front of the unit housing and attached to an inwardly extending shaft, wherein the shaft holds a cam configured to rotate in response to rotation of the operator disconnect handle, wherein the cam comprises first and second arms that extend straight out from the shaft and that reside angularly spaced apart between about 45-135 degrees;
- at least one shutter in serial communication with the first and second arms of the cam whereby the at least one shutter slides right and left in response to a follower that contacts the first and second arms of the cam;
- and
- a stab isolation portal residing above the shaft of the operator disconnect handle, wherein the at least one shutter has a shutter portal, wherein the at leat one shutter is configured to have a position that misaligns the shutter portal with the stab isolation portal to block access to the stab isolation portal when the at least one operator disconnect handle is in an ON position associated with a conduction of electric current through at least one stab of the at least one of the units.
A method of controlling access to a stab isolation access portal of a bucket or unit, comprising:
- rotating an externally accessible operator disconnect handle of the bucket or unit to an ON position associated with conduction of electric current through at least one stab of the bucket or unit, the operator disconnect handle attached to an inwardly extending shaft, the shaft holding a laterally outwardly extending interlock linkage and a cam, wherein in response to the rotation of the operator disconnect handle, (i) an outer end portion of the interlock linkage extends out through an aperture in a sidewall of the bucket or unit and (ii) the cam forces a shutter to slide left or right to block access to the stab isolation access portal associated with a retractable stab.
A method of controlling access to a stab isolation access portal of a dual feeder or starter bucket or unit with right and left operator disconnect handles, the right operator disconnect handle having a right shaft holding a right cam, the left operator disconnect handle having a left shaft holding a left cam, rotating the right and left operator disconnect handles of the bucket or unit to an ON position associated with a conduction of electric current through at least one stab of the bucket or unit, wherein the rotating is carried out so that the right and left operator disconnect handles rotate the right and left cams, respectively, to slide a shutter to a position that blocks access to the stab isolation access portal unless both the right and left operator disconnect handles are in an OFF position associated with a non-conduction of the electric current through the at least one stab of the bucket or unit.
A bucket assembly, comprising:
- a unit housing having a front and opposing laterally spaced apart sidewalls extend rearward of the front of the unit housing;
- at least one operator disconnect handle on the front of the unit housing and each of the at least one operator disconnect handle attached to an inwardly extending shaft, wherein the shaft holds (i) at least one cam configured to rotate in response to a rotation of a respective one of the at least one operator disconnect handle and (ii) an interlock linkage that pivots as the shaft rotates to extend a sufficient distance to extend through an aperture in the sidewall of the unit housing and retract to be inside the unit housing;
- at least one shutter in communication with the at least one cam whereby the at least one shutter slides to the right and left in response to contact with the at least one cam on a respective one of the inwardly extending shaft;
- and
- a stab isolation portal residing above the shaft of the at least one operator disconnect handle, wherein the at least one shutter has a shutter portal, and wherein the at least one shutter is configured to have a position that misaligns the shutter portal with the stab isolation portal to block access to the stab isolation portal when the at least one operator disconnect handle is in the ON position associated with a conduction of electric current through at least one stab of the bucket assembly.
Dependencies are inferred from the claim text.