LED lamp with transparent tube and end cap

Abstract

An LED lamp (300) comprising a transparent tube (330) and an end cap (100) mounted on one end of the transparent tube (330), a pair of pins (310) for electrically and mechanically connecting the LED lamp (300) to a tube holder (420), the pair of pins (310) extending through the end cap (100), a protective cap (200) being provided for protecting the pair of pins (310) from contact by a user, the protective cap (200) comprising a receiving portion (205) having an opening (210) for receiving a portion of the end cap (100) and a connecting portion (230) having an opening (250) for receiving a tube holder (420), and the end cap (100) comprising a locking portion (120) having a cylindrical shape, which can be received in the receiving portion (205) of the protective cap (200). is,a circumferential projection (123) around at least part of the outer circumference of the locking portion (120) and at least one notch (122) on the outer circumference of the locking portion (120), both of which correspond to at least one locking means (220) of the protective cap (200).

Description

Technical area

[0001] The present invention relates to an LED lamp with a transparent tube and an end cap for replacing a fluorescent tube lamp. background

[0002] Conventional fluorescent tube lamps used in conventional luminaire housings have a straight, curved, or round body with a maximum tube length of 2400 mm. Fluorescent tubes are typically low-pressure discharge lamps with an inner coating containing a fluorescent material such as phosphor. The fluorescent tube lamp consists of an airtight glass tube, an enclosed inert gas, and electrodes for igniting the inert gas. At each end of the fluorescent tube is a cover with two symmetrically arranged contact pins to which the electrodes are connected. The fluorescent tube is supplied with power via these two contact pins.

[0003] Replacing a fluorescent tube, e.g., for energy-saving purposes, with a retrofittable LED lamp (hereinafter also referred to as an LED lamp) is becoming increasingly common today. Retrofitting means replacing a fluorescent tube with an LED lamp without modifying the fluorescent tube's luminaire housing. The luminaire housing comprises a base body, at least two tube holders, and the electronic devices necessary for the operation of the fluorescent tube. Replacing the fluorescent tube must not involve the optional requirement of removing the starter, a load, or a ballast, or replacing it with something else.

[0004] When replacing a fluorescent tube with an LED lamp, a problem can arise related to the potential occurrence of electric shock during the LED lamp assembly process. In accordance with electrical safety regulations, luminaire housings are designed so that no live parts can be touched when replacing a fluorescent tube, even if the fluorescent tube housing is not disconnected.

[0005] This requirement must also be met if the fluorescent tube is replaced in such a way that only one end of the tube is in contact with the contacts of one of the tube holders of the luminaire housing, so that the person replacing the tube may possibly touch the other (open) end of the tube.

[0006] This requirement is automatically met with a fluorescent tube, as no current flows through the gas-filled fluorescent tube until the gas inside the tube has been ionized by a voltage pulse. This starting pulse is generated by the ballast. In other words, the gas inside the fluorescent tube is non-conductive before ionization. Thus, the electrical structure of the lamp housing is designed in such a way that the generation of a starting pulse is necessary to electrically connect both ends of the fluorescent tube. Thus, the fluorescent tube's design prevents the risk of electric shock during replacement.

[0007] For LED lamps, this electrical safety requirement is not necessarily met. LED lamps typically comprise a circuit board or equivalent structure on which LEDs and other electronic components and drivers, such as driver devices for the LEDs, are mounted. The purpose of these components is to convert the AC voltage from the power supply into a DC voltage and to control the DC current required by the LEDs. In practice, the LED lamp is energized when one side of the LED lamp is connected to the tube holder of the luminaire housing. In other words, the LED lamp is in a conductive state without a starting pulse. Therefore, when mounting the LED lamp on fluorescent luminaire housings, the contact pins at one end of the LED lamp can be connected to the contacts of a tube holder of the fluorescent luminaire housing, while the other end of the LED lamp can remain outside the fluorescent luminaire housing.As a result, the person installing or replacing the LED lamp may touch the live free pins of the LED lamp.

[0008] US 2011 / 0260614 discloses an LED lamp for replacing a fluorescent tube. The LED lamp includes a safety unit to prevent a voltage from being transmitted through the LED lamp from one end to the other until a voltage supplied from a corresponding tube holder of the lamp housing to the pair of contact pins at each end of the LED lamp has been separately detected. Within the LED lamp is at least one optical line arranged to transmit a control or measurement signal associated with the safety unit from one end of the LED lamp to the other without capacitive leakage currents. However, the safety unit is expensive and can itself malfunction, leading to a risk of electric shock.

[0009] The document US 2015 / 0 008 151 A1 describes an LED lighting system with a modular structure, which enables efficient heat dissipation through an integrated heat sink design with an improved construction. The document US 2012 / 0 106 157 A1 describes a thermal management system for an LED luminaire with a heat sink and an optimized housing design. The document US 4 280 169 A describes a method for producing an improved lighting system using special materials to achieve high energy efficiency and a longer service life. The document WO 2011 / 138 141 A2 describes an LED lighting system with a modular structure for flexible adaptation to different applications, wherein the LED lighting system has an innovative design for optimizing light distribution and heat dissipation.The publication KR 20 2011 001 1338 U describes an LED luminaire with a waterproof housing with special seals and materials, which protects the internal components of the LED luminaire from moisture. Summary of the invention

[0010] In view of the known state of the art, it is an object of the present invention to provide a simple and cost-effective solution to prevent the occurrence of an electric shock for a user when retrofitting an LED lamp to a luminaire housing of a conventional fluorescent tube.

[0011] This object is achieved by an LED lamp with an end cap and a protective cap according to the independent claim, which form a protection system to prevent a user from touching pins. Such an LED lamp with the protection system is easy to manufacture and has low production costs per unit. Preferred embodiments are evident from the dependent claims, the figures, and the description.

[0012] The LED lamp has a transparent tube and an end cap mounted on one end of the transparent tube. A pair of pins for electrically and mechanically connecting the LED lamp to a tube holder extends through the end cap. A protective cap is provided to protect the pair of pins from contact by a user during installation of the LED lamp to a tube holder.

[0013] LED lamps typically comprise a circuit board or equivalent structure on which LEDs and other electronic components and drivers, such as drivers for the LEDs, are mounted. One or both of the first and second pairs of pins may be supported by an end cap on the first and second ends of the LED lamp. The pins typically extend through the end cap so that they can be received by the tube holder. The transparent tube itself can be made of glass or plastic and surrounds the long side of the LED lamp.

[0014] The protective cap has a receiving portion with an opening for receiving a portion of the end cap and a connecting portion with an opening for receiving a tube holder. The end cap includes a locking portion having a cylindrical shape to be received in the receiving portion of the protective cap, a circumferential projection around at least a portion of the outer periphery of the locking portion, and at least one notch on the outer periphery of the locking portion, both of which correspond to at least one locking means of the protective cap.

[0015] The end cap may be round in shape. It may include a mounting portion, a locking portion, and a contact portion. The mounting portion is cylindrical in shape and serves to connect the end cap to the LED lamp tube directly or via an additional fastener.

[0016] The locking portion may be located adjacent to the mounting portion. The locking portion may have a cylindrical shape. It may have one to four or more notches. The notches may be stamped into a support ring protruding from the surface of the locking portion. The notches may be offset by 90 degrees on the circumference of the locking portion or the support ring. The locking portion further includes a circumferential projection around at least a portion of the outer circumference of the locking portion. The at least one notch and the circumferential projection correspond to at least one locking means of a protective cap.

[0017] The contact section, which may be arranged adjacent to the locking section, has an end plate connected to the locking section directly or via an additional cylindrical portion. The end plate has a circumferential shape. It may have a first hole and a second hole for receiving a pair of pins. It may have a beveled edge on the outer radius of the end plate at the interface between the end plate and the locking section or the end plate and the additional cylindrical portion that is part of the contact section. This has the advantage of simplifying the insertion of the locking section into the protective cap.

[0018] The protective cap has a cylindrical first section with a round opening corresponding to the locking section of the end cap. Furthermore, it has a straight second section with a rectangular cross-section and an opening corresponding to a tube holder for an LED lamp. The first section and the second section extend perpendicular to each other and are connected to each other.

[0019] The circular opening of the cylindrical first portion has a wall and an inner surface of the wall, wherein a locking means projects from the inner surface into the circular opening and corresponds to the circumferential projection of the end cap.

[0020] The locking means may be arranged in a hole in the wall. The wall may have at least one opening, preferably four openings offset by 90 degrees. Each locking means may have a resilient support within the opening and connected to the wall. A locking lug, corresponding to a projection of an end cap, may be attached to the bracket.

[0021] In addition, at least one tooth corresponding to a notch in an end cap can be attached to the holder. The tooth provides haptic feedback when rotating the LED lamp. The locking lug and the tooth can protrude into the round opening of the protective cap. The locking lug can be elongated and corresponds to the circumferential projection of the locking section. The tooth is slightly rounded and corresponds to the notch of the locking section.

[0022] The end cap and the protective cap form a protective system. The connected end cap and protective cap prevent contact with live parts, especially the end pins.

[0023] In a preferred embodiment, LED lamps with such a protection system are used. The end cap is used with a lighting device, preferably an LED lamp device with a first end and a second end.

[0024] Such an LED lamp may comprise an array of LEDs, one or a first pair of contact pins at a first end of the LED lamp, and one or a second pair of contact pins at a second end of the LED lamp for electrically and mechanically connecting the LED lamp to a conventional tube holder for fluorescent tubes. The one or the first pair of contact pins may be connected together to form a first circuit, the one or the second pair of contact pins may be connected together to form a second circuit, and an LED driver for powering at least one LED may be connected between the first circuit and the second circuit. The LED driver is powered by the one or the first pair of pins and the one or the second pair of pins.

[0025] The end caps can be permanently attached to the tube itself or with an additional fastener. The LED lamp may further include some electronic devices, which may be part of an LED driver that powers multiple LED modules or an array of LED modules.

[0026] The protective cap can be attached to either end of the LED lamp. When used with an LED lamp, the protective cap and the end cap form a protective system. Brief description of the drawings

[0027] Preferred embodiments of the invention are explained below with reference to the drawings. They show: Fig. 1 shows a perspective view of the end cap. Fig. 2 shows a perspective view of the protective cap. Fig. 3 shows a section of part of the protective cap. Fig. 4 shows a section of the protective cap and the end cap on an LED lamp. Fig. Figure 5 shows a perspective view of the protective cap and end cap on an LED lamp. Fig. Figure 6 shows a perspective view of the protective cap and end cap on an LED lamp. Fig. 7 shows a section of a perspective view of the protective cap and the end cap of an LED lamp in the unlocked position. Fig. Figure 8 shows a section of a perspective view of the protective cap and the end cap of an LED lamp in the locked position. Fig. Figure 9 shows a perspective view of the end cap on an LED lamp and the protective caps on both sides of an LED lamp. Fig. 10 shows a schematic diagram of an LED lamp. Fig. 11 shows a circuit diagram of a conventional fluorescent tube or an LED lamp in the lamp holder. Fig. 12 shows a perspective view of a luminaire housing with an LED lamp. Detailed description of the invention

[0028] Preferred embodiments of the invention are described below with reference to the drawings. The same or similar elements, or elements having the same effect, may be identified by the same reference number in multiple drawings. Repetition of the description of these elements may be omitted to avoid redundant descriptions.

[0029] Fig. 1 shows a perspective view of an end cap 100 of an LED lamp 300. The end cap 100 has a round shape and can be mounted on the end of a tube of the LED lamp (see e.g. Fig. 4). It comprises a mounting portion 110, a locking portion 120, and a contact portion 130.

[0030] The mounting section 110 serves to connect the end cap 100 to the tube 330 of an LED lamp 300 directly or via an additional attachment. The tube 330 is intended to accommodate the electronic components of the LED lamp 300, such as a circuit board and an LED array that ultimately provides the light.

[0031] The locking portion 120 of the end cap 100 has a round shape. In the illustrated embodiment, it has four notches 122 stamped into a support ring 121 that protrudes from the surface of the locking portion 120. The notches 122 are offset by 90 degrees along the circumference of the locking portion 120.

[0032] The contact section 130 includes an end plate 133 that is attached to the locking section 120. The end plate 133 is attached to the locking section 120 via an additional cylindrical portion 124. The cylindrical portion 124 is part of the contact section 130. The end plate 133 has a round shape. It has a first opening 131 and a second opening 132 for receiving a pair of electrical contact pins of the LED lamp 100. The contact pins serve to electrically connect the electronic components of the LED lamp 100 to a luminaire, and in particular to the electrical contacts of a tube holder for an LED lamp of a luminaire.

[0033] The contact section 130 may have a beveled edge 134 on the outer radius of the end plate 133 at the interface between the end plate 133 and the connection area 120. This serves to simplify insertion of the locking section 120 into a protective cap 200, which will be described below with reference to Fig. 2 is explained.

[0034] Fig. Figure 2 shows a perspective view of a protective cap 200. The protective cap 200 has a cylindrical first section 205 with a round opening 210 corresponding to the locking section 120 of the end cap 100. Furthermore, a straight second section 230 with a rectangular cross-section and an opening 250 corresponding to the outer shape of a tube holder 420 for an LED lamp 300. The first section and the second section extend perpendicular to each other and are connected to each other.

[0035] The circular opening 210 of the cylindrical first portion has a wall 212 and an inner surface 211 of the wall 212 with a locking means 220 projecting from the inner surface 211 into the circular opening 210 and corresponding to the circumferential projection 123 of the end cap 100.

[0036] The locking means 220 can be arranged in a hole 215 in the wall 212. The wall 212 can have at least one hole 215, preferably four holes 215 offset by 90 degrees. Each locking means can have an elastic holder 225 within the hole 215 and connected to the wall 212. A locking lug 221, corresponding to a projection 123 of the end cap 100, is attached to the holder 225. Furthermore, at least one tooth 222, corresponding to a notch 122 of an end cap 100, is attached to the holder 225. The tooth 222 serves to provide haptic feedback when rotating the LED lamp 300. The locking lug 221 and the tooth 222 protrude into the round opening 210 of the protective cap 200. The locking lug 221 may be elongated and corresponds to the circumferential projection 123 of the locking portion 120. The tooth 222 is slightly rounded and corresponds to the notch 122 of the locking portion 120.

[0037] Fig. Figure 3 shows a section of the locking means 220. The locking means are located in a hole 215 in the wall 212 and protrude from the inner surface 211. The locking means 220 has an elastic holder 225 within the hole 215, which is connected to the wall 212. A locking lug 221 and a tooth 222 are attached to the holder 225 and protrude into the round opening 210. The locking lug 221 is elongated and corresponds to the circumferential projection 123 of the locking portion 120. The tooth 222 is slightly rounded and corresponds to the notch 122 of the locking portion 120.

[0038] Fig. 4 shows a section of the protective cap 200 and the end cap 100 on an LED lamp 130. The end cap 100 is mounted on the tube 330 of the LED lamp 300 and the protective cap 200 is connected to the end cap 100. The elastic locking means 220 has a detent 221 that engages the projection 123 of the locking portion 120, thereby firmly connecting the protective cap 200 to the end cap 100. The back plate 240 of the protective cap 200 prevents accidental contact with the first pair of pins 310 when replacing the LED lamp.

[0039] Fig. Figure 5 shows a perspective view of the protective cap 200 and the end cap 100 on an LED lamp 300 according to Fig. 4 from an external view.

[0040] Fig. 6 shows a perspective view of the protective cap 200, which is firmly attached to an end cap 100 of an LED lamp 300, from an external view with a lamp housing 400. The protective cap 200 encloses a tube holder 420. The lamp housing has a base body 410 for electrical connection and for receiving electronic components.

[0041] Fig. 7 shows a section of a perspective view of the protective cap 200 and the end cap 100 on an LED lamp 300 in the unlocked position. The end cap 100 is firmly connected to the tube 330 of the LED lamp 300, so that the end cap 100 rotates with the tube 330. To facilitate handling, an arrow 150 is applied to the end cap 100, which corresponds to the position of the pair of pins 310, 320. Therefore, the protective cap 200 does not need to be transparent to allow insertion of the pins 310, 320 into the tube holder 420. The tube holder 420 is locked by inserting the pins 310, 320 into the tube holder 420 and rotating the LED lamp 300. For this purpose, the tube holder 420 has a rotatable insert in a housing. The insert has a groove for inserting the pins 310, 320. In the vertical position, the groove of the insert is aligned with a groove in the tube holder housing.This allows pins 310, 320 to be inserted into the insert. The tube holder 420 is then locked into a horizontal position by rotating the LED lamp 300 90 degrees. In this position, the groove in the insert does not align with the groove in the tube holder housing. The arrow indicates the locked or unlocked state. If the arrow 150 is on the top or bottom of the LED lamp 300, the LED lamp 300 or the tube holder 420 is unlocked. If the arrow 150 is on the side, the LED lamp 300 is locked in the tube holder 420.

[0042] Fig. Figure 8 shows a section of a perspective view of the protective cap 200 and the end cap 100 on an LED lamp 300 in the locked state. The lateral position of the arrow 150 indicates this state.

[0043] Fig. 9 shows a perspective view of an LED lamp 300 with an end cap 100 and a protective cap 200 at each end of the LED lamp 300.

[0044] Fig. 10 shows a schematic structure of an LED lamp 300. The LED lamp 300 includes a first pair of pins 310 and a second pair of pins 320 at each end of the LED lamp 300 as a standard interface for supplying power to the LED lamp 300. The LED lamp 300 further includes an LED driver 360 for supplying power to a plurality of LED modules 370 and for rectifying the AC supply voltage 440. The LED driver 360 is connected to the first pair of pins 310 and the second pair of pins 320.

[0045] Fig. 11 shows a schematic structure of a conventional lighting device 500, which includes a fluorescent tube 510 with a glass tube 511 and a pair of hot cathodes 512 at each end of the fluorescent tube 510 for heating the gas in the glass tube 511. The lighting device 500 further includes a starter 520 and a load 530 for generating a voltage pulse to ignite the fluorescent tube 510. The lighting device 500 is typically connected to an AC mains 540 that provides the supply voltage.

[0046] Fig. 12 shows a conventional lighting device according to Fig. 6 with a lamp housing 400 comprising a base body 410 as a mounting plate with a pair of tube holders 420 (only one is shown). The LED lamp 300 according to Fig.6 is connected to one side and, correspondingly, to the first pair of pins 310, to the tube holder 420. Thus, the free second pair of pins 320 is supplied with power via the LED driver 360, and an electric shock may occur.

[0047] Although the invention has been illustrated and described in detail by the embodiments explained above, it is not limited to these embodiments. Other modifications may be devised by those skilled in the art without departing from the scope of the appended claims.

[0048] In general, “a / an” can be understood as singular or plural, in particular with the meaning “at least one”, “one or more”, etc., unless this is expressly excluded, e.g. by the term “exactly one”, etc.

[0049] In addition, numerical values ​​may include the exact value as well as a usual tolerance interval, unless expressly excluded.

[0050] Features shown in the embodiments, particularly in different embodiments, may be combined or replaced without departing from the scope of the invention. List of reference numbers 100 end caps 110 Assembly section 120 locking section 121 support ring 122 notch 123 lead 124 cylinder section 130 Contact area 131 First Hole 132 Second Hole 133 End plate 134 Beveled edge 150 arrows 200 protective caps 205 First Section 210 Round opening 211 interior surface 212 Wall 215 holes 220 locking devices 221 locking lug 222 tooth 225 bracket 230 Second Section 240 back plate 250 opening 300 LED lamp 310 First pair of pins 320 Second pair of pins 330 pipe 360 LED driver 370 LED modules 400 luminaire housings 410 base body 420 tube holder 500 Conventional lighting device 510 fluorescent tube 511 glass tube 512 hot cathode 520 starters 530 load 540 AC power supply

Claims

[1] LED lamp (300) with a transparent tube (330) and an end cap (100) mounted at one end of the transparent tube (330), a pair of pins (310) for electrically and mechanically connecting the LED lamp (300) to a tube holder (420), the pair of pins (310) extending through the end cap (100), a protective cap (200) being provided to protect the pair of pins (310) from contact by a user, the protective cap (200) comprising a receiving section (205) with an opening (210) for receiving a section of the end cap (100) and a connecting section (230) with an opening (250) for receiving a tube holder (420), and the end cap (100) comprising a locking section (120) having a cylindrical shape, which is located in the receiving section (205) of the protective cap (200) to be recorded,comprising a circumferential projection (123) around at least a part of the outer circumference of the locking section (120) and at least one notch (122) on the outer circumference of the locking section (120), both of which correspond to at least one locking means (220) of the protective cap (200). [2] LED lamp (300) according to claim 1, characterized by , that the end cap (100) has a chamfered edge (134) on the outer radius to improve the insertion of the locking section (120) into the receiving section (205) of the protective cap (200). [3] LED lamp (300) according to claim 2, characterized by , that the locking section (120) has four notches (122). [4] LED lamp (300) according to claim 3, characterized by , that the notches (122) on the circumference of the locking section (120) are offset by 90 degrees. [5] LED lamp (300) according to claim 3 or 4, characterized by, that the locking section (120) has a support ring (121) which protrudes from the surface of the locking section (120) and the notches (122) are embossed in the support ring (121). [6] LED lamp (300) according to claim 1, characterized by , that the locking means (220) of the protective cap (200) has an elastic carrier (225). [7] LED lamp (300) according to claim 6, characterized by , that a locking lug (221) corresponding to a projection (123) of the end cap (100) is attached to the holder (225). [8] LED lamp (300) according to claim 7, characterized by , that at least one tooth (222) corresponding to a notch (122) of the end cap (100) is attached to the holder (225).

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