The invention relates to a light emitting diode (LED) based light usable in a conventional fluorescent lighting fixture.
Fluorescent tube lights are widely used in a variety of locations, such as schools and office buildings. Although conventional fluorescent bulbs have certain advantages over, for example, incandescent lights, they also pose certain disadvantages including, inter alia, disposal problems due to the presence of toxic materials within the glass tube.
LED-based tube lights, which can be used as one-for-one replacements for fluorescent tube lights, have appeared in recent years. One such LED-based replacement light includes LEDs mounted on an elongated circuit board in a semi-cylindrical housing. A U-shaped lens can snap onto the housing to cover and disperse light from the LEDs. The replacement light can include two end caps, where an end cap is dispersed at each longitudinal end of the tube. The end caps generally include a molded plastic cup-shaped body that slides over the end of the tube to secure the end cap to the tube. Additionally, each end cap can include one or more connector pins for electrically and/or mechanically connecting the replacement light with standard fluorescent fixtures. For example, many end caps carry two connector pins for compatibility with fixtures designed to receive standard-sized tubes, such as T5, T8, or T12 tubes.
Embodiments of an LED-based light for replacing a fluorescent bulb in a conventional fluorescent light fixture are disclosed herein. In one embodiment, the LED-based light includes a housing having a first end opposing a second end, a circuit board disposed within the housing and extending along a longitudinal axis of the housing, at least one LED mounted to the circuit board, and at least one end cap disposed on one of the first and second ends of the housing. The end cap includes at least one electrically conductive pin configured for physical and electrical connection to the light fixture. Circuitry is configured to provide a current path between the at least one LED and the at least one electrically conductive pin, and a switch included in the end cap is configured to selectively disconnect the current path.
In another embodiment, the LED-based light includes a housing having a first end opposing a second end, a circuit board disposed within the housing and extending along a longitudinal axis of the housing, at least one LED mounted to the circuit board, and at least one end cap disposed on one of the first and second ends of the housing. The end cap includes at least one electrically conductive pin configured for physical and electrical connection to the light fixture. A pin cover composed of an insulating material is adjacent to the first end and configured to selectively expose and substantially enclose the electrically conductive pin.
Embodiments of a method of installing an LED-based light into a conventional fluorescent light fixture, the LED-based light including a housing having a first end opposing a second end, at least one LED disposed within the housing, a first end cap disposed on the first end of the housing including at least one electrically conductive pin, a second end cap disposed on the second end of the housing including at least one electrically conductive pin, circuitry providing a current path between the first and second end cap's electrically conductive pins, and a switch, are also disclosed herein. The method includes engaging the switch in a first position to disconnect the current path, positioning the first and second end cap's at least one electrically conductive pin into the light fixture, and engaging the switch in a second position to connect the current path.
These and other embodiments will be described in additional detail below.
The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein:
One problem when replacing a fluorescent lamp with a LED-based replacement light is the potential for contact with the exposed connector pins during, for example, installation or relamping. Some lamps, such as fluorescent lamps and their replacements, are automatically prepared to conduct upon installation. Accordingly, if the lighting fixture is energized when one end of the lamp is plugged into the fixture, it is possible that electrical current may flow through the body of the person installing the lamp to ground. Specifically, if one or more pins are exposed while at least one other pin is in electrical contact with the fixture, the person may experience electrical shock if they come in contact with the pins.
Embodiments of the present invention reduce or eliminate the shock hazard potential present in LED-based lights having exposed connector pins.
Each of the disclosed embodiments generally includes a circuit board (not shown), multiple LEDs (not shown) and a housing 30 at least partially defined by a high-dielectric translucent portion. The disclosed embodiments further include a pair of end caps with associated connector pins, which will be discussed in detail below.
The housing 30, as shown in the embodiments of
The circuit board can be an elongated printed circuit board. Multiple circuit board sections can be joined by bridge connectors to create the circuit board. The circuit board can be slidably engaged with the housing 30, though the circuit board can alternatively be clipped, adhered, snap- or friction-fit, screwed or otherwise connected to the housing 30. For example, the circuit board can be mounted on a heat sink that is attached to the housing 30. Also, any other type of circuit board may be used, such as a metal core circuit board. Alternatively, instead of a circuit board, other types of electrical connections (e.g., wires) can be used to electrically connect the LEDs to a power source.
The LEDs can be surface-mount devices of a type available from Nichia, though other types of LEDs can alternatively be used. For example, one or more organic LEDs can be used in place of or in addition to the surface-mount LEDs. The LEDs can be mounted to the circuit board by solder, a snap-fit connection, or other means. The LEDs can produce white light. However, LEDs that produce blue light, ultra-violet light or other wavelengths of light can be used in place of white light emitting LEDs.
The number of LEDs can be a function of the desired power of the light and the power of the LEDs. For a 48″ light, for example, the number of LEDs can vary from about five to four hundred such that the light outputs approximately 500 to 3,000 lumens. However, a different number of LEDs can alternatively be used, and the light can output a different amount of lumens. The LEDs can be evenly spaced along the circuit board, and the spacing of the LEDs can be determined based on, for example, the light distribution of each LED and the number of LEDs. Alternatively, a single or multiple LEDs can be located at one or both ends of the light.
While the light can be compatible with standard sized fluorescent fixtures, an LED-based light having another shape, such as an incandescent bulb or another type of light, can alternatively be used. Also, other types of light sources, such as fluorescent or incandescent based light sources, can be used instead of or in addition to the LEDs.
The end caps 102 can be the sole physical connection between the light 100 and the fixture. The end caps 102 can also be electrically connected to the circuit board to provide power to the LEDs. Although each end cap 102 is shown as including two pins 104, one or two of the total four pins that are located on both ends of the housing 30 can be “dummy pins” that do not provide an electrical connection. Alternatively, other types of electrical connectors can be used, such as an end cap carrying a single pin. Also, while the end caps 102 are shown as including cup-shaped bodies, the end caps 102 can have a different configuration (e.g., the end caps 102 can be shaped to be press fit into the housing 30). One or both of the end caps 102 can additionally include electric components, such as a rectifier and filter.
Circuitry can provide a current path in the light 100. The current path can be between the ends of the light 100, for example between one or more pins 104 of the end caps 102. The current path can include one or more pins 104 of the end cap 102, LEDs, the circuit board or wires, or any suitable combination thereof. For example, the current path can be between a pin 104 and the LEDs, between a pin 104 and the circuit board, or between the LEDs and the circuit board. One or both of the end caps 102 include a switch 106 that can selectively disconnect the current path. The switch 106 includes a sliding button 108 that can be selectively engaged between an “ON” position and an “OFF” position. The current path is disconnected when the button 108 is slid into the “OFF” position and is connected when the button 108 is slid into the “ON” position. Before the light 100 is installed in a light fixture, the switch 106 can be set (e.g., by the manufacturer or the installer) to the “OFF” position such that an open circuit condition exists, for example, between the ends of the tube. While the switch 106 is shown as a manual slide switch, any other suitable switch may be used. For example, in some embodiments the switch may be a push-button switch or a toggle switch. Additionally, the switch 106 may be labeled to warn the user not to energize the lamp (i.e. set the switch to “ON”) until the lamp is fully installed. The label may be placed such that it must be removed before energizing the switch.
The switch 106 can break a current path at any point in the circuitry of the light 100. For example, one end of the switch 106 can be connected to the pins 104 of one of the end caps 102 and the other end of the switch 106 can be connected to the circuit board. Accordingly, when the switch 106 is in the “OFF” position, there will be no current flowing from the circuit board to the pins 104 and vice versa. However, the switch can be connected in any suitable manner to create the open circuit condition within light 100. As one example, the switch can break the current path between two series-connected LEDs.
When the installer places one end of the tube into an energized fixture and when the switch 106 is in the “OFF” position, the installer can remove or reduce the risk of shock if he comes into contact with the pins 104 by ensuring that the button 108 of the switch 106 is in the “OFF” position. Accordingly, as discussed previously, there will be no current flowing to the pins 104. Once the installer places both ends of the tube into the fixtures, the installer can then move the switch 106 from “OFF” to “ON” thereby reestablishing a closed circuit connection between the ends of the tube (i.e. permitting current to flow through light 100). Likewise, when the installer decides that he would like to remove the light 100 from the fixture, the installer can move the switch from the “ON” to “OFF” position to establish the open circuit connection.
The collar 206 circumferentially extends around and is rotatable about the end cap 202. Although the collar 206 is shown in
The collar 206 also includes an outer knurled surface 212. Alternatively, the collar 206 may include another suitable gripping contour, or may not include any gripping contour at all. In other embodiments, the collar may include a protrusion that aids a user in grasping the collar. The protrusion may be used in conjunction with an “ON” indicator for signifying when the switch has been actuated and an “OFF” indicator for signifying when the switch has not been actuated.
Similar to the first embodiment, when the installer places one end of the tube 30 into an energized fixture, the installer can remove or reduce the risk of shock if he comes into contact with the pins 204 by rotating the collar 206 after both ends of the light 200 have been placed into the fixture.
The light 400 also includes a pin cover 406 constructed from an insulating material such as, for example, a thermoplastic. As illustrated, the cover 406 has a cylindrical shape and is concentric with the housing 30 and the end cap 402. The cover 406 has an outer diameter that is slightly smaller than the outer diameter of housing 30. However, the pin cover can also include a number of different shapes and sizes to cover pins 404.
The cover 406 can be attached to a spring or other type of biasing mechanism (not shown) located within the tube 30, and allows the cover 406 to retract into the end cap 402 in a first direction D1 when a force is exerted, and correspondingly allows the cover 406 to travel in a second direction D2 to a protracted position (illustrated in phantom line) when the force is no longer applied to the end cap 402. The cover 406, when in the protracted position, covers the pins 406 before the light 400 is installed. The cover 406 can telescope within the end cap 402 during installation. Specifically, when the installer installs one of the ends of the light tube 400 into the fixture, the force exerted by pressing the respective end of the light tube 400 into the fixture urges the cover 406 in the first direction D1 which axially retracts the pin cover 406 into the end cap 402.
Accordingly, after a force has been applied to the cover 406, the pins 404 can be exposed through apertures 408 in the cover 406. The apertures 408 can be sized to pass the pins 404, but can be sized to not permit other objects to pass. For example, the apertures can have a 0.25″ diameter such that the installer's fingers or tools cannot pass through. It follows that the cover 406 protects the installer from coming into contact with the pins 404 and can avoid any possible electrical shock.
Similar to the fourth embodiment, the cover 506 is attached to a spring or biasing element (not shown) that causes the pin cover 506 to retract, as discussed previously. Specifically, the end cap 502 is retractable in a first direction D1 when a force is exerted, and the cover 506 travels in a second direction D2 to a protracted position when the force is no longer applied to the end cap 502. The pins 504 can be exposed through apertures 508 in the cover 506, where the apertures 508 are sized to pass the pins 504, but can be sized not to permit other objects to pass. It follows that the cover 506 protects the installer from coming into contact with the pins 504 and can avoid any possible electrical shock.
The lever 614 can be attached either directly or indirectly to the cover 606 such that when the lever 614 is moved in the first direction D1, the lever 614 forces the cover 606 to retract into the end cap 602. When the lever 614 is moved in the second direction D2, the lever 614 urges the cover 606 out of the end cap 602, causing the cover 606 to protract. The lever 614 can be located in a position relative to the pins 604 such that the installer's fingers are unlikely to come in contact with the pins 604 when the cover 606 is retracted. In alternative embodiments, a button, knob or other suitable device can be used in lieu of lever 614.
For example, the locking mechanism can prevent the cover 706 from retracting into the end cap 702 when the locking mechanism is in a locked (i.e. latched) position. The locking mechanism can be locked or latched when, for example, there is no force exerted to inwardly press the lever 714 (i.e. by the installer). The locking mechanism permits the cover 706 to retract into the end cap 702 when the locking mechanism is in an unlocked (i.e. unlatched) position. The locking mechanism can be unlocked or unlatched, when, for example, the installer exerts a force to inwardly press the lever 714. The locking mechanism is any type of device that can selectively prevent the lever 714 from sliding within the groove 718, and can include a variety of mechanisms such as, for example, a latch, a pin, or a spring (all not shown).
In one embodiment of the locking mechanism, when the cover 706 is in the protracted position and the locking mechanism is in the latched position, the locking mechanism includes a spring and a pin that can engage with a latch. To remove the pin from the latch, the installer can inwardly press and hold the lever 714, which causes the locking mechanism to release the pin. Accordingly, the installer can (while simultaneously pressing the lever 714), move the lever 714 in the first direction D1, which permits the cover 706 to retract within end cap 702 or within the second direction D2, which permits the cover 706 to protract from within end cap 702. Of course, other locking mechanisms are available that can be used instead of or in addition to the locking mechanism described above.
A manual slide button 814 slidable within a groove 820 enables the pin covers 806 to protract and retract into the end cap 802. Similar to the sixth embodiment, the button 814 can be engaged directly or indirectly with covers 806 such that when the button 814 is moved in the first direction D1 the covers 806 retract into the end cap 802. When the button 814 is moved in the second direction D2, the covers 806 protract from the end cap 802.
A manual slide button 914 slidable within a groove 920 enables the pins 904 to protract and retract. The button 914 can be engaged directly or indirectly with pins 904 such that when the button 914 is moved in the first direction D1, the pins 904 retract into the end cap 902, and when the button 914 is moved in the second direction D2 the pins 904 protract from the end cap 902. The pins 904 can be in the retracted position when received by the manufacturer, or can be moved into the retracted position before installation into a lighting fixture by an installer. When the installer installs one or both the ends of the light tube 900 into the fixture, the installer can move the manual slide button 914 to the second position D2, thereby protracting the pins 904 from the end cap 902. Once the pins 904 have been protracted from the end cap 902 and are exposed, the pins 904 can be in electrical communication with the lighting fixture. Similarly, when the installer wants to remove the light tube 900, the button 914 is moved in the first direction D1 to retract the pins 904 before removing the light tube 900 from the fixture. Although a manual slide button is illustrated, a different device (e.g. manual slide lever) may be used as well. Alternatively, a spring-loaded device including an elastic element may be used instead to protract or retract the pins.
The collar 1006 also includes an outer knurled surface 1012. Alternatively, the collar 1006 may include another suitable gripping contour, or may not include any gripping contour at all. In other embodiments, the collar may include a protrusion that aids a user in grasping the collar 1006.
The collar 1006 is rotatable about a longitudinal axis A-A of the light 1000. The collar 1006 is rotated about the axis A-A in a first clockwise direction R1 permitting the pins 1004 to protract from the respective aperture 1009 of the end cap 1002. When the collar 1006 is rotated in a second counterclockwise direction R2 the pins 1004 can be retracted in the respective apertures 1009 of the end cap 1002. Alternatively, in another embodiment the collar 1006 can be rotated in the first direction R1 to retract the pins 1004 and rotated in the second direction R2 to protract the pins 1004 if desired.
The current path is disconnected when the button 1108 is slid into the “OFF” position and/or the moveable pin 1110 is urged into the second direction D2, where the moveable pin 1110 is protracted from the aperture 1109 of the end cap 1102. The current path is connected when the button 1108 is slid into the “ON” position and the moveable pin 1110 is urged into the first direction D1, where the moveable pin 1110 is retracted into the aperture 1109 of the end cap 1102.
Referring to
Although not illustrated, the collar 1206 may include an outer knurled surface that provides a textured surface that is easier for a user to grasp. Alternatively, another suitable gripping contour may be provided as well. The collar 1206 is rotatable about a longitudinal axis A-A of the light 1200. The collar 1206, instead of sliding button 1108 illustrated in the eleventh embodiment, acts as a switch to move the internal circuitry of the light 1200 between an “ON” position and an “OFF” position. The collar 1206 is rotated about the axis A-A in a first clockwise direction R1 to the “ON” position and is rotated in a second counterclockwise direction R2 to the “OFF” position. Alternatively, in another embodiment the collar 1206 can be rotated in the first direction R1 to the “OFF” position and rotated in the second direction R2 to the “ON” position if desired.
When the installer places an end of the light 1200 into an energized fixture, the moveable pin 1210 contacts a fixture connector such that the moveable pin 1210 is depressed in the first direction D1 into the aperture 1209 of the end cap 1202. Similar to the eleventh embodiment illustrated in
The exposed portion of the outer surface 1312 of the moveable pin 1310 includes a generally triangular or pointed profile when protracted from the end cap 1302. When the installer places an end of the light 1300 into an energized fixture, the sloped outer surface 1312 of the moveable pin 1310 contacts a fixture connector such that the moveable pin 1310 is depressed in the first direction D1 and into the aperture 1309 of the end cap 1302, thereby closing the circuitry located within the light 1300. When the lamp 1300 is removed from the fixture, the moveable pin 1310 protracts from the end cap 1302 in the second direction, thereby opening the circuit.
When in the first position P1, an open circuit condition is created. The pin 1404 can be rotated about the axis A-A to the second position P2 to close the circuit, thereby allowing current to flow to the pin 1404. Specifically, a bottom end 1410 of the pin 1404 contacts an electrical contact (not shown) located in the end cap 1402 when the pin 1404 is upright and in the second position P2, thereby allowing current to flow in the light 1400. When the pin 1404 is rotated about the axis A-A to the first position P1, the bottom end 1410 of the pin 1404 moves away from and no longer makes contact with the electrical contact, thereby opening the circuit. Although an electrical contact is discussed, the bottom end 1410 of the pin 1404 may also contact a switch actuator to open and close the circuitry of the light 1400 as well.
At least one of the pins 1404 is set to the first position P1 when the installer places an end of the light 1400 into an energized fixture. The fixture connector makes contact with the pin 1404 such that the pin 1404 rotates about the axis A-A at the angle θ and into the second position P2, which closes the circuitry located within the light 1400 and allowing current to flow to the pins 1404. The lighting fixture holds the pins 1404 upright in the second position P2 until the light 1400 is removed from the fixture. When removed from the fixture, the pins 1404 rotate about the axis A-A back to the first position P1, where current can no longer flow to the pins 1404.
The covering assembly 1610 includes a cover 1612 that is constructed from an insulating material such as, for example, a thermoplastic. The cover 1612 can be generally C-shaped to cover the pins 1602 and is held in place by a spring loaded connecting member 1614. The connecting member 1614 includes a first end 1616 and a second end 1618, where the connecting member 1614 is attached to the covering 1612 at the first end 1616 and to the end cap 1602 at the second end 1618. The connecting member 1614 is a spring loaded or other type of biased mechanism that rotates about the end axis A-A when the installer places the light tube 1600 into the fixture. Specifically, when the cover 1612 contacts the light fixture, the connecting member 1614 is rotated about the end axis A-A such that the connecting member 1614 springs into the position illustrated in
The covering assembly 1710 may also include a biasing member 1716 such as, for example, a spring that assists the cover 1712 in springing into a closed position to cover the pins 1704. Specifically, when the cover 1712 contacts the light fixture, the cover 1712 springs into a retracted position, thereby exposing the pins 1704. Once the pins 1704 are exposed, the pins 1704 can be in electrical communication with the lighting fixture. The lighting fixture can hold the cover 1712 in place to keep the pins 1704 exposed. Similarly, when the installer removes the light tube 1700, the connecting member 1716 is biased or spring loaded such that the connecting member 1716 springs back to cover the pins 1704, as the lighting fixture no longer holds the cover 1712 in place. The biasing member 1716 is biased in a direction R1, and provides a biasing force that assists the cover 1712 in springing back to a closed position to cover the pins 1704. Alternatively, in another embodiment, the biasing member 1716 is biased in a second direction R2 that is opposite the first direction R1. In this alternative embodiment, the biasing member 1716 assists the cover 1712 in springing to an open position to reveal the pins 1704.
Referring the
As the installer installs one of the ends of the light 1900 into the fixture, the force exerted by pressing the respective end of the light tube 1900 into the fixture actuates one or both of the end caps 1902 in the first direction D1, which axially retracts the end caps 1902 to a smaller second height H2, and is illustrated in
The installer first moves the slide 2016 within the groove 2018, thereby unlocking the biasing mechanism and allowing the end caps 2002 to actuate from the first height H1 to the second height H2. The installer then places the ends of the light tube 2000 into the lighting fixture, where the force exerted by pressing the respective end of the light tube 2000 into the fixture urges one or both of the end caps 2002 in the first direction D1, and the pins 2004 electrically connect with the internal circuitry located within the tube 30. In alternative embodiments, a button, knob or other suitable device can be used in lieu of slide 2016.
As the installer installs one of the ends of the light tube 2100 into the fixture, the force exerted by pressing the respective end of the light tube 2100 into the fixture actuates one or both of the pins 2104 in the first direction D1, and axially retracts the pins 2104 into a smaller second height H2. When moved inwardly towards the first direction D1, the pins 2104 electrically connect with the internal circuitry located within the tube 30. The electrical circuit is closed, thereby allowing current to flow to the pins 2104.
The installer first moves the slide 2216 within the groove 2218, thereby unlocking the biasing mechanism and allowing the pins 2204 to actuate from the first height H1 to the second height H2. The installer then places the ends of the light tube 2200 into the lighting fixture, where the force exerted by pressing the respective end of the light tube 2200 into the fixture urges one or both of the pins 2204 in the first direction D1. The pins 2204 can then electrically connect with the internal circuitry located within the tube 30. In alternative embodiments, a button, knob or other suitable device can be used in lieu of slide 2216.
Each end cap 2302 can include an outer axial end 2304 defining a pair of apertures 2306, though the end 2304 can define a different number of apertures 2306. Each end cap 2302 can also include a base 2308 spaced axially inward (i.e., toward a center of a light the end cap 2302 is attached to along axis 23-23 as shown in
A pin 2316 can extend through each aperture 2306, and the pins 2316 can be spaced apart, sized, and otherwise configured to engage with a standard fluorescent fixture. Each pin 2316 can be made from an electrically conductive material (e.g., copper, aluminum, or another conductor) and can include a tip 2317 made from an insulating material. While a two pin 2316 and two aperture 2306 configuration can be used for many common fixtures, other numbers of pins 2316 can alternatively be used (e.g., a single pin 2316 configuration). Each pin 2316 can extend through the base 2308 to a side of the base 2308 opposite the end 2304. Alternatively, the pins 2316 can be in electrical connection with components on an opposing side of the base 2316 from the end 2304 without extending therethrough, such as by being connected to wires that pass across the base 2308.
One or more of the pins 2316 can be electrically connected to a pair of switch contacts 2318, which are fixed to the base 2308 in the example shown in
The insulating sleeves 2320 can be connected to a platform 2328. The connection can include an extension 2330 portion of the sleeves 2320 having a tab 2332, and the extension 2330 can pass through an aperture 2334 in the platform 2328 such that the tab 2332 is on an opposing side of the platform 2328 from the sleeves 2320. The length of the extension 2330 along axis 23-23 can be as long as or longer than the distance between the distal end 2314 and the ramped section 2312 of the tang 2310.
The platform 2328 can be slidably arranged in the end cap 2302 between the end 2304 and the base 2308. The platform 2328 can define a slot 2336. One end of the slot 2336 can be axially aligned with an end of the ramped section 2312 of the tang 2310 such that the slot 2336 overlays the distal end 2314 of the tang 2310 but not its ramped section 2312. Additionally, the flange 2326 of the insulating sleeves 2320 can extend a portion of the distance across the slot 2336. An opposing end of the slot 2336 can be further radially outward than the flange 2326. One or more biasing members, such as the illustrated springs 2338 positioned around respective pins 2316, can bias the platform 2328 toward the end 2304.
A sliding actuator 2340 can be joined to or formed integrally with the platform 2328. The sliding actuator 2340 can include a knob 2342 extending to an exterior of the end cap 2302 and slidable along a slot 2344 defined by the end cap 2302. The knob 2342 can thus be accessible to, e.g., an installer of a light including the end cap 2302. The knob 2342 can include a knurled surface to enhance an installer's grip. The sliding actuator 2340 can be positioned relative to the switch contacts 2318 such that when the knob 2342 is urged along the slot 2344 a predetermined distance toward the platform 2328, the sliding actuator 2340 contacts the switch contacts 2318 and urges the switch contacts 2318 into the open position.
A latch receiver 2346 can also be joined to or formed integrally with the platform 2328. The latch receiver 2346 can include a protuberance 2348 spaced from the platform 2328. Alternatively, instead of the protuberance 2348, the latch receiver 2346 can include another structure that can be selectively engaged, such as an aperture.
The end cap 2302 can include a latch 2350. The latch 2350 can define a release button 2352 extending to an exterior of the end cap 2302 and a chamfered hook 2354 on the interior of the end cap 2302. The latch 2350 can be moveable between a resting position and an actuated position. The latch 2350 can also include a biasing member, e.g., a spring, that biases the latch 2350 toward the resting position. The latch 2350 can be positioned such that the chamfered hook 2354 engages the protuberance 2348 of the latch receiver 2346 when the latch receiver 2346 is urged a predetermined distance toward the base 2308. The chamfered hook 2354 can have a generally triangular shape or another shape that allows the protuberance 2348 of the latch receiver 2346 to pass in one direction and to prevent the latch receiver 2346 from moving in an opposing direction. Actuation of the release button 2352 can bias the latch 2350 such that the chamfered hook 2354 disengages the protuberance 2348.
When a light including the end caps 2302 is not installed in a fixture, the insulating sleeves 2320 can be in the pin-protecting position. For example, when a light including the end caps 2302 is purchased the insulating sleeves 2320 can come in the pin-protecting position. With the insulating sleeves 2320 in the pin-protecting position, the insulating sleeves 2320 are fully extended and protect the pins 2316. Additionally, the tang 2310 contacts the flange 2326, thereby hindering movement of the insulating sleeves 2320 away from the pin-protecting position.
Also with the insulating sleeves 2320 in the pin-protecting position, the sliding actuator 2340 is not engaged with the switch contacts 2318, which remain in the closed position. However, since the insulating sleeves 2320 protect the pins 2316 in the pin-protecting position, the risk of an electrical shock is reduced or eliminated with the insulating sleeves 2320 in the pin-protecting position even though the switch contacts 2318 are in the closed position. Further, installation of a light including the end caps 2302 would be difficult or not possible with the insulating sleeves 2320 in the pin-protecting position because the light would not likely fit into a fixture with the insulating sleeves 2320 fully protracted to the pin-protecting position. Also with the insulating sleeves 2320 in the pin-protecting position the latch receiver 2346 is spaced from and not engaged with the latch 2350.
Prior to installing a light including the end caps 2302 in a fixture, an installer can move the insulating sleeves 2320 from the pin-protecting position to a pin-exposing position by urging the knob 2342 away from the end 2304. As the knob 2342 is initially urged away from the end 2304, the insulating sleeves 2320 do not move because the tab 2332 of the sleeves 2320 is spaced from the platform 2328 by the length of the extension 2330. However, the initial movement of the knob 2342 moves the platform 2328 relative to the tang 2310, and the distal end 2314 of the tang 2310 passes through the slot 2336 in the platform 2328. The platform 2328 then contacts the ramped section 2312 of the tang 2310. Due to the angle of the ramped section 2312, the platform 2328 urges the tang 2310 laterally through the slot 2336 in the platform 2336, bending the tang 2310. With the tang 2310 bent, the distal end 2314 of the tang 2310 no longer contacts the flange 2326 of the insulating sleeves 2320.
After the knob 2342 moves the length of the extension 2330 of the insulating sleeves 2320, the sliding actuator 2340 contacts the tab 2332 of the insulating sleeves 2320. Once the sliding actuator 2340 contacts the tab 2332, additional movement of the knob 2342 toward the base 2308 moves the insulating sleeves 2320. Thus, the insulating sleeves 2320 are not prevented by the tang 2310 from moving toward the base 2308.
As mentioned above, when the knob 2342 is moved a predetermined distance, the sliding actuator 2340 engages the switch contacts 2318 and biases the switch contacts 2318 to their open position. With the switch contacts 2318 in their open position, the electric circuit including the pins 2316 is open. As a result, current would not flow through the pins 2316 even if a current were applied to the pins 2316, such as if the light were installed in the fixture. Since current does not flow through the pins 2316 when the insulating sleeves 2320 are in the pin-exposing position, the risk of shock to an installer is reduced or eliminated.
Also when the insulating sleeves 2320 are in the pin-exposing position, the latch 2350 can engage the latch receiver 2346. As a result, even though the springs 2338 urge the insulating sleeves 2320 from the pin-exposing position to the pin-protecting position by applying a force to the platform 2328, the engagement between the latch 2350 and latch receiver 2346 can retain the insulating sleeves 2320 in the pin-exposing position. By retaining the insulating sleeves 2320 in the pin-exposing position, the switch contacts 2318 are retained in the open position and the risk of shock remains reduced or eliminated.
With the insulating sleeves 2320 in the pin-exposing position, the installer can position the light including the end caps 2302 in the fixture. Since the switch contacts 2318 remain in the open position, current does not flow through the pins 2316. Once the light is in the fixture, the installer can actuate the release button 2352. Actuation of the release button 2352 can eliminate the engagement between the latch 2350 and latch receiver 2346, which in turn can allow the springs 2338 to bias the platform 2328 toward the end 2304. Movement of the platform 2328 toward the end 2304 also moves the sliding actuator 2340, which can allow the switch contacts 2318 to return to the closed position. The insulating sleeves 2320 can move toward the pin-protecting position, although the fixture that the light is now installed in can prevent the sleeves 2320 from reaching the pin-protecting position. As such, the pins 2316 can remain partially exposed. Thus, the pins 2316 can be electrically connected to the fixture and, since the switch contacts 2318 are in the closed position, to other components in the light such as LEDs.
Upon removal of the light from the fixture, the springs 2338 urge the insulating sleeves 2320 back to the pin-protecting position. Thus, the end caps 2302 can reduce or eliminate the shock risk associated with LED-based lights prior to installation, during installation, after installation, and upon removal. In alternative examples, the end cap 2302 can include other features. For example, a note can be included on the end cap 2302 behind the knob 2342 when the insulating sleeves 2320 are in the pin-protecting position that becomes visible when the knob 2342 is moved toward the base 2308 and that alerts an installer to press the release button 2352 after installing the light. Also in alternative examples, the end cap 2302 need not include certain features, such as the tang 2310 and/or the latch 2350 and latch receiver 2346.
The above-described embodiments have been described in order to allow easy understanding of the invention and do not limit the invention. On the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structure as is permitted under the law.
This application is a continuation of U.S. patent application Ser. No. 13/284,008 filed Oct. 28, 2011, which claims priority to U.S. Provisional Patent Application No. 61/407,962, filed Oct. 29, 2010, both of which are incorporated herein by reference in their entireties.
Number | Date | Country | |
---|---|---|---|
61407962 | Oct 2010 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 13284008 | Oct 2011 | US |
Child | 14012047 | US |