SWITCHES WITH INTEGRAL OVERCURRENT PROTECTION COMPONENTS
Switches with integrated overcurrent protection elements are described. The overcurrent protection elements can include a bimetallic structure which is configured to move between a first shape and a second shape in response to heating. The overcurrent protection element can be rotationally coupled to a rotary knob in some embodiments. In other embodiments, the overcurrent protection element can be fixed, and the rotary knob can be connected to one or more rotatable conductive structures within the rotary switch.
1 . A rotary switch including an integrated overcurrent protection device, the switch comprising:
a housing;
a first terminal extending into the housing and electrically connected to a first terminal contact;
a second terminal extending into the housing and electrically connected to a second terminal contact;
an overcurrent protection element located within the housing;
a knob extending through a through-hole in the housing and rotatable with respect to the housing; and
a rotatable conductive element located within the housing and rotationally coupled to the knob to rotate in response to rotation of the knob, the conductive element rotatable between a first angular orientation in which the conductive element is electrically connected to the first and second terminal contacts and a second angular orientation in which the conductive element is not electrically connected to at least one of the first and second terminal contacts.
2 . The rotary switch of claim 1 , wherein the overcurrent protection element is not rotationally coupled to the knob.
3 . The rotary switch of claim 1 , wherein the overcurrent protection element comprises a bimetallic element configured to change shape in response to electrical current above a specified limit
4 . The rotary switch of claim 3 , wherein the conductive element comprises the overcurrent protection element.
5 . The rotary switch of claim 4 , wherein the bimetallic element is configured to change shape between a first position in which the bimetallic element is electrically connected to the first and second terminal contacts when the overcurrent protection element is in the first angular orientation, and a second position in which the bimetallic element is curved such that the bimetallic element is not electrically connected to at least one of the first and second terminal contacts when the overcurrent protection element is in the first angular orientation.
6 . The rotary switch of claim 3 , wherein the bimetallic element is configured to change shape between a first position in which the bimetallic element is electrically connected between two contacts within the housing and a second position in which the bimetallic element is not electrically connected to at least one of the two contacts within the housing.
7 . The rotary switch of claim 6 , wherein the overcurrent protection element comprises a bimetallic element configured to change shape in response to electrical current above a specified limit.
8 . The rotary switch of claim 1 , wherein the overcurrent protection element is configured to, in response to an overcurrent condition, change shape from a first position in which the bimetallic element is electrically connected between two contacts within the housing to a second position in which the bimetallic element is not electrically connected to either of the two contacts within the housing.
9 . The rotary switch of claim 8 , wherein the overcurrent protection element comprises an internal bias to change shape back to the first position when the overcurrent protection element has sufficiently cooled from the overcurrent condition which triggered the change in shape to the second position.
10 . The rotary switch of claim 1 , wherein a portion of the overcurrent protection element is directly connected to a terminal within the housing or a conductive component electrically connected to said terminal, wherein the overcurrent protection element is configured to, in response to an overcurrent condition, change shape from a first position in which the bimetallic element is electrically connected between said terminal or a conductive component electrically connected to said terminal and a second terminal within the housing or a conductive component electrically connected to said second terminal to a second position in which the bimetallic element is not electrically connected to said second terminal or said conductive component electrically connected to said second terminal.
11 . The rotary switch of claim 10 , wherein the direct connection between the portion of the overcurrent protection and the terminal within the housing or the conductive component electrically connected to said terminal is axially aligned with an axis of rotation of the knob.
12 . The rotary switch of claim 11 , wherein the direct connection between the portion of the overcurrent protection and the terminal within the housing or the conductive component electrically connected to said terminal comprises at least one of a pin, weld, or rivet.
13 . The rotary switch of claim 1 , wherein the housing comprises a cover, and wherein the through-hole in the housing comprises a circular hole extending through said cover.
14 . The rotary switch of claim 1 , further comprising a third terminal extending into the housing and electrically connected to a third terminal contact.
15 . The rotary switch of claim 14 , wherein the overcurrent protection element is configured to be placed in electrical communication with the first terminal contact at a first stationary contact location and in electrical communication with the third terminal contact at a second stationary contact location, wherein the rotatable conductive element comprises an arcuate bus bar, wherein the arcuate bus bar is movable in response to rotation of the knob between a first angular orientation in which the arcuate bus bar is electrically connected to the first terminal contact and the second terminal contact and a second orientation in which the arcuate bus bar is not in electrical communication with either or both of the first terminal contact or the second terminal contact.
16 . The rotary switch of claim 15 , wherein the arcuate bus bar includes at least a first longitudinally protruding section and a second longitudinally protruding section, the first and second longitudinally protruding sections located closer to the first, second, and third terminal contacts than a recessed portion of the arcuate bus bar extending between the first and second longitudinally protruding sections, and wherein, when the arcuate bus bar is at the first angular orientation, the first longitudinally protruding section is in contact with the first terminal contact and the second longitudinally protruding section is in contact with the second terminal contact.
17 . The rotary switch of claim 14 , further comprising a fourth terminal extending into the housing and electrically connected to a fourth terminal contact.
18 . The rotary switch of claim 17 , wherein the overcurrent protection element is configured to be placed in electrical communication with the first terminal contact at a first stationary contact location and in electrical communication with the third terminal contact at a second stationary contact location, and wherein the rotatable conductive element comprises an arcuate bus bar.
19 . The rotary switch of claim 18 , wherein the arcuate bus bar is movable between:
a first angular orientation in which the arcuate bus bar is electrically connected to the first terminal contact and the second terminal contact,
a second angular orientation in which the arcuate bus bar is not in electrical communication with any of the first terminal contact, the second terminal contact, or the fourth terminal contact;
a third angular orientation in which the arcuate bus bar is electrically connected to the first terminal contact, the second terminal contact, and the fourth terminal contact; and
a fourth angular orientation in which the arcuate bus bar is electrically connected to the first terminal contact and the fourth terminal contact.
20 . The rotary switch of claim 17 , wherein the overcurrent protection element is configured to be placed in electrical communication with the first contact point at a first stationary contact location and in electrical communication with the second terminal contact at a second stationary contact location, and wherein the rotatable conductive element comprises a first arcuate bus bar, the switch further comprising a second arcuate bus bar rotationally coupled to the first arcuate bus bar to rotate along with the first arcuate bus bar in response to rotation of the knob, and wherein the first and second arcuate bus bars are movable between:
a first angular orientation in which the first arcuate bus bar is electrically connected to the first terminal contact and the third terminal contact and the second arcuate bus bar is electrically connected to the fourth terminal contact and the first contact point,
a second angular orientation in which the first arcuate bus bar is electrically connected to the first terminal contact, the second terminal contact, and the third terminal contact, and the second arcuate bus bar is electrically connected to the fourth terminal contact and the first contact point, and
a third angular orientation in which the first arcuate bus bar is in electrical communication with the first terminal contact, and is not in electrical communication with any of the second terminal contact, the third terminal contact, the fourth terminal contact, or the first contact point, and in which the second arcuate bus bar is only in electrical communication with the second terminal contact, and is not in electrical communication with any of the first terminal contact, the third terminal contact, the fourth terminal contact, or the first contact point.