LED lamp

Abstract

An LED lamp (1) is attachable to and detachable from a socket (101), and comprises a light source unit (20), a circuit (30), and a lens (50) that controls light emitted from the light source unit (20). The LED lamp (1) further comprises: a bottomed cylindrical outer cover (10); a base pin (15) that protrudes from the outer cover (10) and is electrically connected to the circuit (30); and a cylindrical light-shielding hood (70) that includes a light-shielding part (71) extending from an opening of the outer cover (10) and includes an insertion part (72) inserted into the cylinder of the outer cover (10).

Description

LED lamp

[0001] The present disclosure relates to an LED lamp, and more particularly to an LED lamp with a built-in power supply circuit.

[0002] In the past, when attaching a light shading hood to a lighting device using an LED, a configuration has been proposed in which an LED lamp and a fixture that covers the LED lamp are used and the light shading hood is attached to the fixture. For example, Patent Document 1 discloses a configuration in which a light shading hood is attached to a fixture that incorporates an LED lamp.

[0003] Japanese Patent Application Laid-Open No. 2002-358815

[0004] However, if an LED lamp and a fixture are used and a shading hood is attached to the fixture, the number of parts increases, which leads to an increase in the size of the lighting device and a decrease in assembly efficiency. It is desirable to have a configuration in which the number of parts is reduced and the device can be made smaller in size in an LED lighting device with a shading hood.

[0005] The LED lamp according to the present disclosure is characterized in that it is detachably attached to a socket and comprises a light source unit including an LED element, a circuit for supplying power to the light source unit, a lens for controlling the light emitted from the light source unit, a cylindrical outer cover with a bottom that houses the light source unit, the circuit, and the lens, a base pin that protrudes from the outer cover and is electrically connected to the circuit, a light-shielding portion that extends from an opening in the outer cover, and a cylindrical light-shielding hood that includes an insertion portion that is inserted into the tube of the outer cover.

[0006] According to the LED lamp of the present disclosure, it is possible to provide an LED lighting device with a light-shielding hood that has a small number of parts.

[0007] 9 is a perspective view of a lighting device using an LED lamp of embodiment 1 attached to a wiring duct rail. FIG. 10 is a perspective view of the LED lamp of embodiment 1, showing a state in which the light-shielding hood has been removed. FIG. 11 is an exploded perspective view of the LED lamp of embodiment 1. FIG. 12 is a cross-sectional view of the LED lamp of embodiment 1. FIG. 13 is a perspective view of the light-shielding hood and lens constituting the LED lamp of embodiment 1, showing a state in which the light-shielding hood has been removed from the lens. FIG. 14 is a perspective view of the light-shielding hood and lens of embodiment 1, showing a state in which the light-shielding hood has been attached to the lens. FIG. 15 is an enlarged view showing a second joint between the light-shielding hood and lens of embodiment 1. FIG. 16 is a front view of the light-shielding hood and lens of embodiment 2, showing a state in which the light-shielding hood has been attached to the lens. FIG. 17 is an enlarged view showing a joint between the light-shielding hood and lens of embodiment 2. FIG. 18 is a cross-sectional view taken along line A-A' in FIG.

[0008] An example of an embodiment of an LED lamp according to the present disclosure will be described in detail below with reference to the drawings. It should be noted that the scope of the present disclosure includes configurations that selectively combine the components of the multiple embodiments and variations described below. For convenience of explanation, the axial direction in the description of the embodiment is defined as the direction from the base pin side toward the lens side along the side surface of the outer cover. Additionally, the side where the lens is located relative to the base pin is defined as the upper side.

[0009] FIG. 1 is a perspective view of an LED lamp 1 according to an embodiment, showing the state in which the LED lamp 1 is attached to a connector 100 including a socket 101. As shown in FIG. 1, the LED lamp 1 and the connector 100 constitute a spotlight. A spotlight is generally a lighting device that provides concentrated illumination in the direction in which the lamp is facing. In the example shown in FIG. 1, the connector 100 constituting the spotlight is attached to a wiring duct rail 104. The LED lamp 1 may also be attached to a spotlight socket provided on, for example, the ceiling or wall of a building.

[0010] The connector 100 includes a socket 101, a plug 102 attached to a wiring duct rail 104, and a shaft 103 connecting the socket 101 and the plug 102, with the shaft 103 extending from the radial center of the cylindrical plug 102. The socket 101 is formed in a cylindrical shape like the plug 102, but has a larger diameter than the plug 102 because a portion of the LED lamp 1 is inserted into the socket 101. As will be described in more detail below, inserting a portion of the LED lamp 1 into the socket 101 allows the outer peripheral surfaces of the LED lamp 1 and the socket 101 to be flush with each other, improving the design of the light.

[0011] The connector 100 has a swivel mechanism that rotates the socket 101 at a predetermined angle relative to the shaft 103. The swivel mechanism may be configured so that the socket 101 rotates at a predetermined angle around the tip of the shaft 103 as the axis of rotation, or may be configured so that the socket 101 is rotatable around the axis. Alternatively, the shaft 103 may be rotatable relative to the plug 102. The swivel mechanism of the connector 100 allows the LED lamp 1 to be aimed at a desired location for light irradiation when the connector 100 is attached to the wiring duct rail 104.

[0012] The LED lamp 1 includes a cylindrical outer cover 10 with a bottom, and a light-shielding hood 70 inserted into the cylindrical outer cover 10. As will be described in detail later, in this embodiment, the light-shielding hood 70 is detachable from the lens 50. The LED lamp 1 is also detachable from the socket 101. The LED lamp 1 includes base pins 15 (see FIG. 3 , etc., described later) protruding from the outer cover 10, and the base pins 15 are inserted into pin insertion portions of the socket 101 to attach the LED lamp 1 to the socket 101, and the LED lamp 1 and the socket 101 are electrically connected.

[0013] The LED lamp 1 has a structure in which a light source unit 20 (see FIG. 3 described later), a lens 50, etc. are housed inside a tube of an outer cover 10. The outer cover 10 forms the external appearance of the LED lamp 1 and also functions as a housing that houses the light source unit 20, the lens 50, etc. In the embodiment illustrated in FIG. 1 , the outer cover 10 of the LED lamp 1 forms the outer cover of a spotlight. In other words, the outer cover 10 forms the external appearance of the spotlight. Note that conventionally known spotlights have a structure in which an LED lamp is housed inside a tube of a cylindrical cover with a bottom, and the outer cover of the LED lamp does not form the external appearance of the spotlight.

[0014] With the LED lamp 1, the outer cover 10 forms the exterior of the spotlight, eliminating the need for a cover to enclose the lamp and allowing for a significantly smaller diameter spotlight. Furthermore, the LED lamp 1 is easily attached to and detached from the socket 101, eliminating the need to, for example, reach into the cover tube to replace the lamp or disassemble the lighting device to replace the lamp. The outer cover 10 and the shading hood 70 are cylindrical, with a constant outer diameter, in the portions that appear on the exterior of the spotlight. The outer cover 10, the shading hood 70, and the socket 101 all have substantially the same outer diameter, and their outer peripheral surfaces are flush with one another. A spotlight using the LED lamp 1 has a stylish design that creates a unified overall appearance.

[0015] As described above, the LED lamp 1 includes a lens 50 that controls the light emitted from the light source unit 20. The lens 50 has a light emission surface 52 that is circular in a plan view. In this specification, "plan view" means a view perpendicular to the emission surface 52 of the lens 50, unless otherwise specified. A protrusion 53 for attaching and detaching the lamp is formed on the emission surface 52. When removing the LED lamp 1 from the socket 101, the protrusion 53 is used to apply a rotational load to the lens 50, causing the LED lamp 1 to rotate relative to the socket 101, thereby allowing the LED lamp 1 to be removed. When attaching the LED lamp 1 to the socket 101, the protrusion 53 can be used to attach the LED lamp 1 to the socket 101 by rotating the LED lamp 1 in the opposite direction to that used for removal.

[0016] In the case of the spotlight illustrated in Figure 1, the socket 101 of the connecting fixture 100 is exposed and not embedded in the ceiling, wall, etc., so when attaching or detaching the LED lamp 1 to or from the socket 101, the outer cover 10 of the LED lamp 1 can be grasped and the lamp can be rotated.

[0017] FIG. 2 is a perspective view of the LED lamp 1, showing a state in which the shading hood 70 has been removed. As shown in FIG. 2, the shading hood 70 is configured to be detachable. The shading hood 70 includes a shading portion 71 extending from the opening of the outer cover 10 and an insertion portion 72 inserted into the cylindrical portion of the outer cover 10. As will be described in detail later, the shading hood 70 is attached to the lens 50 within the cylindrical portion of the outer cover 10. In other words, the shading hood 70 is detachably attached to the lens 50. The insertion portion 72 of the shading hood 70 is formed with engaging protrusions 73a and 73b that engage with the shading hood fixing portions 60a and 60b of the lens 50 (see FIG. 5, etc., described later).

[0018] The shading hood 70 is generally applied to spotlights and has the function of covering the periphery of the opening of the outer cover 10 to block light from diffusing beyond the intended target. The shading hood 70 may be a metal member or a resin member. The shading hood 70 is made of the same material as the outer cover 10 and has the same color as the outer cover 10, for example.

[0019] The light-shielding portion 71 extends in the axial direction from the opening of the outer cover 10 to block unnecessary light. The light-shielding portion 71 is formed in a cylindrical shape having the same outer diameter as the outer cover 10, and the outer peripheral surface of the light-shielding portion 71 is flush with the outer peripheral surface of the outer cover 10. The axial length of the light-shielding portion 71 is not particularly limited and is set appropriately depending on the size of the LED lamp 1, etc. An example of the axial length of the light-shielding portion 71 is 10 mm or more and 40 mm or less. The axial length of the light-shielding portion 71 may be shorter than the axial length of the insertion portion 72, but in this embodiment, it is longer than the axial length of the insertion portion 72.

[0020] The insertion portion 72 is formed in a cylindrical shape like the light-shielding portion 71, but its outer diameter is smaller than that of the light-shielding portion 71. For this reason, a step is formed on the outer peripheral surface of the light-shielding hood 70. Because the insertion portion 72 is inserted into the cylindrical interior of the outer cover 10, the outer diameter of the insertion portion 72 is smaller than the inner diameter of the outer cover 10. However, it is preferable that the outer diameter of the insertion portion 72 be close to the inner diameter of the outer cover 10 to the extent that insertion into the outer cover 10 is not hindered. The inner diameter of the light-shielding hood 70 is, for example, constant over the entire axial length, and the insertion portion 72 is formed to be thinner than the light-shielding portion 71.

[0021] Most of the insertion portion 72, for example, 90% or more or 95% or more of the axial length of the insertion portion 72, is inserted into the outer cover 10, but the insertion portion 72 protrudes slightly from the inside of the outer cover 10 so that the light-shielding hood 70 can be securely fixed to the lens 50. In this case, it is possible to prevent the outer cover 10 and the light-shielding portion 71 from coming into contact with each other, which would interfere with the attachment of the light-shielding hood 70. A small gap exists between the outer cover 10 and the light-shielding portion 71, but as long as this gap is 10% or less or 5% or less of the axial length of the light-shielding portion 71, it has little effect on the design.

[0022] The outer peripheral surface of the insertion portion 72 faces the inner peripheral surface of the outer cover 10 with a small gap between them. The outer peripheral surface of the insertion portion 72 may contact the inner peripheral surface of the outer cover 10 as long as it does not interfere with insertion into the outer cover 10. To prevent dust and debris from entering, the difference between the outer peripheral surface of the insertion portion 72 and the inner peripheral surface of the outer cover 10 may be minimized. This also reduces light leakage. The insertion portion 72 is preferably configured to abut against the inner peripheral surface of the outer cover 10 at least when a force is applied in the radial direction of the light-shielding hood 70. In this case, the outer cover 10 can withstand a load applied in the radial direction of the light-shielding hood 70, effectively preventing damage to components and detachment of the light-shielding hood 70. The outer diameter of the insertion portion 72 is, for example, 90% or more, or 95% or more, of the inner diameter of the outer cover 10.

[0023] The LED lamp 1 includes a pair of base pins 15 protruding from the bottom of an outer cover 10 formed in a cylindrical shape with a bottom. The base pins 15 extend from one axial end of the outer cover 10 along the axial direction of the outer cover 10. The base pins 15 are metallic power supply pins that are electrically connected to a circuit 30 (see FIG. 3 , etc., described later) for supplying power to the light source unit 20, and receive power from a socket of the lighting device and send the power to the circuit 30. The base pins 15 have an expanded diameter at their tip so that they can be caught in a pin insertion portion of the socket.

[0024] Two base pins 15 are provided side by side in the radial direction of the outer cover 10. The distance between the pair of base pins 15 in the radial direction (hereinafter sometimes referred to as the "pin distance") is not particularly limited, but is, for example, 40 mm or less, 35 mm or less, or 30 mm or less. The pin distance means the shortest distance between the central axes of the two pins. Examples of suitable ranges for the pin distance are 15 mm to 40 mm, 20 mm to 35 mm, or 25 mm to 30 mm. If the pin distance is within these ranges, it becomes easy to reduce the diameter of the lighting device.

[0025] The outer cover 10 is generally formed in a generally cylindrical shape with a bottom, but has a reduced diameter at the bottom side from which the base pins 15 protrude. The outer cover 10 has a large diameter portion 11 that forms the exterior of the spotlight, and a small diameter portion 12 that is inserted into the socket 101. The outer cover 10 further has a protrusion 13 that protrudes axially from the small diameter portion 12. The light-shielding hood 70 may be a metal member or a resin member. An example of the resin that constitutes the outer cover 10 is polybutylene terephthalate (PBT).

[0026] The outer cover 10 is formed with, in order from the opening side, a large diameter portion 11, a small diameter portion 12, and a protruding portion 13, and the protruding portion 13 is also inserted into the socket 101. The socket 101 has a pin insertion portion and a housing portion for the protruding portion 13. The difference in outer diameter between the small diameter portion 12 and the protruding portion 13 is greater than the difference in outer diameter between the large diameter portion 11 and the small diameter portion 12. The axial length of the large diameter portion 11 is preferably 75% or more of the axial length of the outer cover 10, and may be 75% or more and 95% or less, or 80% or more and 90% or less.

[0027] The outer diameter of the large diameter portion 11 is substantially the same as the outer diameter of the light-shielding portion 71 of the light-shielding hood 70 and the outer diameter of the socket 101, and their outer peripheral surfaces are flush. The outer diameter of the small diameter portion 12 is preferably close to the inner diameter of the socket 101 to the extent that insertion into the socket 101 is not hindered. The convex portion 13 is cylindrically formed in the radial center of the outer cover 10 and has a protrusion 13a formed on its outer peripheral surface. The protrusion 13a catches on the socket 101 in the same way as the base pin 15, improving the reliability of the fixation of the LED lamp 1 to the socket 101.

[0028] Fig. 3 is an exploded perspective view of the LED lamp 1. As shown in Fig. 3, the LED lamp 1 includes a light source unit 20 including an LED element 21, a circuit 30 for supplying power to the light source unit 20, a holder 40 for holding the light source unit 20, and a lens 50 for controlling the light emitted from the light source unit 20. As described above, the LED lamp 1 includes a cylindrical outer cover 10 with a bottom that houses the light source unit 20, the circuit 30, the holder 40, and the lens 50, and a base pin 15 that protrudes from the outer cover 10 and is electrically connected to the circuit 30. The LED lamp 1 also includes a heat sink 25 that dissipates heat from the light source unit 20 and a cylindrical circuit holder 35 that holds the circuit 30. The LED lamp 1 also includes a detachable light-shielding hood 70.

[0029] As will be described in detail later, the LED lamp 1 has a configuration in which the outer cover 10 and the light-shielding hood 70 are detachable. The light-shielding hood 70 is connected to the lens 50 inside the outer cover 10 by a connecting protrusion 73a (attachment portion). The light-shielding hood 70 has a light-shielding portion 71 and an insertion portion 72 whose outer diameter is smaller than that of the light-shielding portion 71, and is held in a state in which the insertion portion 72 is inserted into the tube of the outer cover 10. Furthermore, in the held state, the light-shielding portion 71 and the outer cover 10 form a substantially identical, continuous outer surface, making it possible to achieve a good appearance.

[0030] The LED lamp 1 is a small-diameter lamp, for example, having a diameter of 50 mm or less. The large-diameter portion 11 of the outer cover 10, which forms the exterior of the LED lamp 1, has a diameter of, for example, 35 mm or more and 45 mm or less. The outer cover 10 is longer in the axial direction than in the radial direction, and its axial length may be 1.3 to 1.7 times the diameter (diameter of the large-diameter portion 11). The circuit holder 25 and the holder 40 are made of resin primarily composed of PBT or the like, and the heat sink 25 is made of metal primarily composed of aluminum or the like.

[0031] Because the LED lamp 1 is long in the axial direction, if the components are assembled using the bottom side of the outer cover 10 as the reference position, such as the boundary between the large diameter portion 11 and the small diameter portion 12 of the outer cover 10, it becomes difficult to assemble the lens 50 in the intended position, which can result in problems such as large variations in light distribution between each product. Therefore, in the LED lamp 1, the lens 50 is fixed to the holder 40 and forms a module together with the holder 40. This makes the distance between the light source unit 20 and the lens 50 constant.

[0032] The LED lamp 1 includes an LED module 2 composed of a light source unit 20, a holder 40, and a lens 50. The holder 40 is formed in a cylindrical shape with a bottom, and includes a base 41 forming the bottom of the cylinder, and a cylinder wall 42 standing on the outer periphery of the base 41. The base 41 has an opening 43 formed in the radial center and fixing claws formed around the opening 43. The light source unit 20 is disposed in the radial center from the underside of the base 41 so as to close the opening 43, and is held by fixing claws formed around the periphery of the opening 43. The holder 40 holding the light source unit 20 is fixed to a heat sink 25 using screws 46, and then the lens 50 is fixed to the holder 40 to form the LED module 2.

[0033] The LED module 2 is disposed closer to the opening than the axial center of the outer cover 10. A heat sink 25 that is long in the axial direction is housed closer to the bottom of the outer cover 10 than the LED module 2. In other words, the lens 50 is attached at a position away from the bottom of the outer cover 10, but because the light source unit 20, holder 40, and lens 50 are integrated to form the LED module 2, the distance between the light source unit 20 and the lens 50 can be managed with high precision, and the distance is not affected by assembly errors of other components.

[0034] The light source unit 20 includes an LED element 21 and a substrate 22 on which the LED element 21 is mounted. One example of a suitable light source unit 20 is a COB (chip on board) type light-emitting diode device for illumination. For example, a plurality of LED elements 21 are mounted in the center of the surface of a substantially square substrate 22, forming a light-emitting unit that is circular in plan view. A pair of electrodes is provided around the light-emitting unit, and wiring extending from the circuit 30 is connected to the electrodes. The light source unit 20 is fixed to the base 41 of the holder 40 so that the light-emitting unit including the LED element 21 is exposed from the opening 43 of the holder 40 and faces the opening of the outer cover 10.

[0035] The heat sink 25 is a member to which the holder 40 is screwed and functions as a heat dissipation member that dissipates heat from the light source unit 20. The heat sink 25 is a cylindrical body with a bottom, including a base 26 to which the holder 40 is fixed and a cylindrical wall 27 that stands on the outer periphery of the base 26 and extends in the opposite direction from the lens 50. The heat sink 25 extends long in the opposite direction from the lens 50, thereby effectively dissipating heat from the light source unit 20 while suppressing thermal effects on the lens 50. In addition, in this embodiment, the surface of the base 26 to which the holder 40 is fixed serves as a reference surface for intersection determination when assembling the lens 50. Because the distance between the lens 50 and the reference surface is short, the lens 50 is less susceptible to the effects of component processing accuracy and assembly errors of other components, allowing the lens 50 to be accurately assembled in the desired position.

[0036] A screw hole 26a and a wire insertion hole 26b are formed in the base 26 of the heat sink 25. A screw 46 that fixes the holder 40 is fastened into the screw hole 26a, and a wire extending from the circuit 30 is passed through the wire insertion hole 26b. The light source unit 20 is pressed against the base 26 by screwing the holder 40 to the base 26, and an excellent heat conduction path is formed between the light source unit 20 and the heat sink 25. It is preferable that thermal grease or a thermal dissipation sheet be interposed between the light source unit 20 and the base 26.

[0037] The cylindrical wall 27 of the heat sink 25 is formed in a substantially cylindrical shape and houses a circuit holder 35 that holds the circuit 30. The outer peripheral surface of the cylindrical wall 27 is formed with locking holes 28 used to secure the circuit holder 35, and with guide grooves 29 extending in the axial direction. The guide grooves 29 are grooves into which the intra-cylinder protrusions 14 formed on the outer cover 10 fit, and are formed at positions that overlap with the locking holes 28. In other words, the locking holes 28 are formed in the guide grooves 29. In this embodiment, the locking holes 28 are used to secure the outer cover 10 and the circuit holder 35 together.

[0038] The circuit 30 is a power supply circuit that converts AC current from a commercial power source into DC current for lighting the LED elements 21. The circuit 30 includes a circuit board 31 and circuit components 32 mounted on the circuit board 31. Base pins 15 are connected to the ends of the circuit board 31, and AC current is supplied to the circuit 30 from the socket 101 via the base pins 15. The circuit components 32 include switching elements, choke coils, capacitors, etc. Note that capacitors have lower heat resistance than other circuit components 32 such as choke coils.

[0039] The circuit board 31 has, for example, a substantially rectangular shape and is held by the circuit holder 35 with its longitudinal direction aligned with the axial direction of the outer cover 10. A pair of base pins 15 are provided protruding from one longitudinal end of the circuit board 31 toward the bottom of the outer cover 10. The capacitor is sandwiched between the pair of base pins 15 and, like the base pins 15, is mounted protruding from one longitudinal end of the circuit board 31 toward the bottom of the outer cover 10. In the LED lamp 1, the circuit board 31 is inserted into a board fixing portion 36 formed within the cylindrical circuit holder 35, and the base pins 15 are held by a base pin fixing portion 37. This holds the circuit 30 within the cylindrical circuit holder 35.

[0040] The circuit holder 35 is a substantially cylindrical member that holds the circuit 30 and is fixed to the heat sink 25 that covers the outside of the holder. The circuit holder 35 has a board fixing portion 36 formed inside the cylinder, a base pin fixing portion 37 formed at the axial end, and a fixing piece 38 that engages with the heat sink 25. The board fixing portion 36 includes a groove that extends in the axial direction and is formed in two places on the inner surface of the circuit holder 35. Each board fixing portion 36 holds both widthwise ends of the circuit board 31 inserted in the groove. Two base pin fixing portions 37 are provided corresponding to a pair of base pins 15, and have semicircular grooves into which flanges formed on the base pins 15 fit.

[0041] The fixing piece 38 is a portion separated from the rest of the cylindrical wall by two slits extending in the axial direction of the circuit holder 35, and is elastically deformable in the radial direction. A protrusion that engages with the heat sink 25 is formed at the tip of the fixing piece 38. The fixing pieces 38 are formed at two locations that face each other in the radial direction of the circuit holder 35. After the circuit 30 is fixed inside the cylindrical circuit holder 35, the circuit holder 35 is inserted into the cylindrical heat sink 25, whereby the protrusions of the fixing piece 38 fit into the locking holes 28 of the heat sink 25, and the circuit holder 35 is fixed to the heat sink 25.

[0042] 4 is a cross-sectional view of the LED lamp 1 taken along the axial direction and the radial direction of the outer cover 10. FIG. 4 is a cross-sectional view of the LED lamp 1 taken along the first radial direction in which the pair of base pins 15 are aligned.

[0043] As shown in FIG. 4 , the LED lamp 1 has an internal structure in which a cylindrical heat sink 25 with a bottom is housed in the bottom side of the outer cover 10, and the LED module 2 is fixed to the base 26 of the heat sink 25. The heat sink 25 is housed in the large-diameter portion 11 of the outer cover 10. As described above, a circuit holder 35 holding a circuit 30 is fixed within the cylindrical heat sink 25. A portion of the circuit holder 35 protrudes from the cylindrical heat sink 25 into the small-diameter portion 12 of the outer cover 10, and a portion of the circuit components 32 extends into the protrusions 13. For example, a heat-sensitive capacitor is inserted into the protrusions 13. Alternatively, a component that generates more heat than the other circuit components 32 may be housed in the protrusions 13.

[0044] The small diameter portion 12 of the outer cover 10 has an outer diameter and an inner diameter smaller than those of the large diameter portion 11, and a step is formed on the inner peripheral surface of the outer cover 10 at the boundary between the large diameter portion 11 and the small diameter portion 12. The cylindrical wall 27 of the heat sink 25 is formed to fit along the inner peripheral surface of the large diameter portion 11 and extend close to the step. A flange 39 that protrudes radially outward and catches on the step is formed on the outer peripheral surface of the circuit holder 35. In this embodiment, the flange 39 abuts on the step of the outer cover 10, thereby regulating the positions of the circuit holder 35, the circuit 30 held by the circuit holder 35, and the base pins 15 connected to the circuit 30 relative to the outer cover 10.

[0045] A heat sink 25 with a circuit holder 35 fixed inside a cylinder is inserted into the outer cover 10. At this time, the heat sink 25 is restricted relative to the outer cover 10 by an inner-cylinder protrusion 14 (see FIG. 3 ) provided on the inner surface of the outer cover 10. A through hole 12a through which the base pin 15 passes is formed in the bottom of the outer cover 10 (the bottom of the small diameter portion 12). The LED lamp 1 is designed so that, with the heat sink 25 fixed to the outer cover 10, the base pin 15 protrudes from the through hole 12a to the outside of the outer cover 10.

[0046] The LED module 2 is fixed to the base 26 of the heat sink 25 by using screws 46 (see FIG. 3 ) in a holder 40 that holds the light source unit 20. Screw insertion holes (not shown) are formed in the holder 40, through which the screws 46 pass. The base 26 of the heat sink 25 is also formed with screw holes 26a (see FIG. 3 ), through which the screws 46 are fastened, and wire insertion holes 26b, through which wires extending from the circuit 30 pass. The LED module 2 does not have a structure for fixing to the outer cover 10.

[0047] An adhesive 49 is filled between the LED module 2 and the outer cover 10. For example, the adhesive 49 is filled in the gap between the outer peripheral surface of the holder 40 and the inner peripheral surface of the outer cover 10 after the holder 40 is screwed to the heat sink 25. The adhesive 49 is also pressed against the lens 50 fixed to the holder 40, filling the gap between the outer peripheral surface of the LED module 2 and the inner peripheral surface of the outer cover 10 and joining the LED module 2 and the outer cover 10.

[0048] The adhesive 49 is not particularly limited, but is preferably primarily composed of silicone resin from the viewpoints of adhesion, durability, etc. Two-component curing adhesives or stimulus curing adhesives can be used as the silicone-based adhesive. The lens 50 of the LED module 2 is fixed by the adhesive 49, but to more reliably prevent the lens 50 from falling off even if the adhesive strength of the adhesive 49 decreases due to aging, the lens 50 is fixed to the holder 40. Furthermore, by providing a fixing structure for the holder 40 and the lens 50, the distance between the light source unit 20 and the lens 50 can be regulated with high precision.

[0049] The LED module 2 is disposed, for example, within a range of 30% or less, or 20% or less, of the axial length of the outer cover 10 from the opening of the outer cover 10. That is, 70% or more of the internal space of the axial length of the outer cover 10 is occupied by the circuit 30 and the heat sink 25. Substantially all of the components of the LED lamp 1, including the LED module 2, heat sink 25, circuit 30, and circuit holder 35, are housed inside the cylindrical outer cover 10. Therefore, the axial length of the outer cover 10 is substantially equal to the axial length of the LED lamp 1. The axial length of the LED lamp 1 is not particularly limited, but is, for example, 50 mm to 80 mm.

[0050] The configurations of the lens 50 and the light-shielding hood 70 of the first embodiment will be described in detail below with reference to FIGS.

[0051] The light-shielding hood 70 is detachably attached to the lens 50. The engaging protrusions 73a (mounting portion) and 73b (mounting portion) are fitted into the light-shielding hood fixing portions 60a and 60b, respectively, to form a first engaging portion and a second engaging portion, thereby combining the light-shielding hood 70 and the lens 50. The light-shielding hood 70 is molded using resin or metal. The lens 50 is molded using resin or glass. One axial end of the outer periphery 54 of the lens 50 is formed with an outer periphery protrusion 55 that protrudes radially outward beyond the other axial end.

[0052] The shape and installation position of the engagement protrusions 73a and 73b will now be described. The engagement protrusions 73a and 73b are both formed to be continuous with the insertion portion 72 and protrude from the lower end (one axial end) of the insertion portion 72. The engagement protrusions 73a and 73b extend downward from the lower end of the insertion portion 72 and are bent at a substantially right angle in the circumferential direction of the light-shielding hood 70, forming an L-shape. The engagement protrusions 73a and 73b are bent in the same circumferential direction. The outer peripheral surfaces of the engagement protrusions 73a and 73b and the insertion portion 72 are smoothly continuous. The tip of the engagement protrusion 73a is provided with a claw 74a to stably maintain the attached state, while the engagement protrusion 73b does not have such a protrusion.

[0053] The shape and installation positions of the light hood fixing portions 60a, 60b will be described. The light hood fixing portions 60a, 60b are provided at positions corresponding to the engagement protrusions 73a, 73b on the outer peripheral surface of the outer peripheral protrusion 55. The light hood fixing portions 60a, 60b include recesses 61a, 61b and restriction protrusions 62a, 62b, respectively. The recesses 61a, 61b are recessed areas provided in the outer peripheral protrusion 55, and the restriction protrusions 62a, 62b are portions that protrude outward from the recesses 61a, 61b.

[0054] The procedure for attaching the light-shielding hood 70 to the lens 50 will now be described. While holding the light-shielding hood 70 so that its center line is roughly aligned with that of the lens 50, the light-shielding hood 70 is brought closer to the lens 50 from above along the axial direction. At this time, the rotation angle of the light-shielding hood 70 relative to the lens 50 is adjusted so that the engagement protrusions 73a and 73b can be inserted into the recesses 61a and 61b, respectively.

[0055] The light shielding hood 70 can be attached by bringing it close to the lens 50 from above, inserting the engagement protrusions 73a and 73b into the recesses 61a and 61b, respectively, and then rotating the light shielding hood 70 relative to the lens 50. In this embodiment, three engagement protrusions (mounting portions) are used, including the engagement protrusions 73a and 73b, but other numbers may be used. A larger number of mounting portions allows for more stable and secure attachment. Furthermore, a smaller number of mounting portions makes attachment and detachment easier. Considering both the stability of the attachment of the light shielding hood 70 and its ease of attachment and detachment, three or four mounting portions are preferable.

[0056] When the light-shielding hood 70 is rotated relative to the lens 50, the tip ends of the engagement protrusions 73a and 73b facing the rotation direction come into contact with the outer peripheral convex portion 55, restricting further rotation and fixing the hood 70 in place. Alternatively, excessive rotation may be restricted by the restricting protrusion 62a in this case.

[0057] Furthermore, the upward movement of the engaging protrusions 73a and 73b is restricted by the restricting protrusions 62a and 62b, which makes it possible to prevent the light-shielding hood 70 from unintentionally coming off the lens 50.

[0058] When the light-shielding hood 70 is assembled to the lens 50 and attached to the outer cover 10, the insertion portion 72 substantially abuts the inner circumferential surface of the outer cover 10. Here, "substantially abutting" refers to both a state in which the insertion portion 72 abuts the inner circumferential surface of the outer cover 10 and a state that is considered to be abutting (e.g., a gap of less than 0.5 mm between the outer circumferential surface of the insertion portion 72 and the inner circumferential surface of the outer cover 10). Typically, the light-shielding hood 70 is assembled to the lens 50 after the LED lamp 1, including the lens 50 and the light-shielding hood 70, has already been assembled. Therefore, since the insertion portion 72 substantially abuts the inner circumferential surface of the outer cover 10, alignment of the engagement protrusions 73a and 73b with the recesses 61a and 61b is facilitated. Furthermore, the insertion portion 72 also serves as a guide during rotation, allowing for smoother attachment and detachment. Furthermore, the insertion portion 72 prevents foreign objects such as insects and dust from entering the lamp, which improves quality reliability and reduces deterioration of appearance. Furthermore, when a load acts in the radial direction of the light-shielding hood 70, the load can be received by the outer cover 10, which effectively prevents damage to components, the light-shielding hood 70 from falling off, and the like.

[0059] When the light-shielding hood 70 is combined with the lens 50 and attached to the outer cover 10, the outer peripheral surface of the light-shielding portion 71 becomes substantially continuous with the outer peripheral surface of the outer cover 10. As a result, despite the configuration being simply a light-shielding cover attached to a lamp, it is possible to obtain a lighting device with a clean, pleasing appearance with few irregularities, similar to that of a fixture that includes a lamp inside.

[0060] A structure for restricting rotation in the direction opposite to the attachment direction when the light shielding hood 70 is combined with the lens 50 will be described. The light shielding hood 70 and the lens 50 can be combined by rotating them. The state before rotation (i.e., before attachment) is shown in FIG. 7B , and the state after rotation (i.e., after attachment) is shown in FIG. 7A . The engagement protrusion 73a has a claw 74a at its tip in the direction of rotation during attachment. After rotation, the claw 74a engages with the tip of the restricting protrusion 62a in the direction of rotation. In this embodiment, the restricting protrusion 62a is formed with a gap between it and the outer peripheral protrusion 55, and the claw 74a fits into the gap and is hooked onto the restricting protrusion 62a. This configuration makes it possible to restrict movement in the direction opposite to that during attachment. In other words, the claw 74a and the restricting protrusion 62a form a rotation restricting portion that restricts rotation in the direction opposite to that during attachment.

[0061] The provision of a rotation restriction portion prevents rotation in the opposite direction to that at the time of attachment, thereby preventing the light hood 70 from unintentionally falling off the lens 50. Alternatively, the restricted state can be released by applying an appropriate rotational force, making it possible to attach and detach the light hood 70 as needed. If the light hood 70 is attached by means of resin hardening or screw fastening, it is difficult for a general user to attach or detach it, but according to this embodiment, even a general user without special skills or tools can easily attach and detach it.

[0062] When using a spotlight, there is a demand for using multiple different types of shading hoods depending on the installation location and purpose, and even in such situations, the great advantage is that ordinary users can easily replace them (without having to ask a construction company, etc.) Furthermore, the force with which the rotation restricting part restricts rotation can be adjusted as appropriate by changing the width of the tip of the engaging protrusion 73a and the shape and size of the claw 74a.

[0063] The total number of engagement protrusions (mounting portions), including the engagement protrusions 73a and 73b, may be one or two or more. In this case, the number of engagement protrusions 73a with claws 74a that restrict rotation in the opposite direction and the number of engagement protrusions 73b without claws 74a may be selected appropriately depending on the usage situation and purpose. Having more claws 74a provides a more stable and secure hold, but having too many claws 74a may require excessive force when removing the hood. One suitable example is a configuration in which two engagement protrusions 73a with claws 74a and one engagement protrusion 73b without claws 74a are provided. In this embodiment, two engagement protrusions 73a are arranged radially opposite each other on the hood 70, and the engagement protrusion 73b is provided at a position substantially equidistant from the two engagement protrusions 73a.

[0064] The configuration of the lens 80 and the light-shielding hood 90 of the second embodiment will be described in detail below with reference to Figures 8 to 10. Differences from the first embodiment will be mainly described below.

[0065] The shape and installation position of the fixing piece 93 of the light-shielding hood 90 will be described. The fixing piece 93 forms a substantially rectangular frame with an opening 95, and is provided in the lower region of the insertion portion 92. In addition, notches 94 are provided on both sides of the fixing piece 93 in the circumferential direction to allow the fixing piece 93 to undergo appropriate elastic deformation. The outer peripheral surface of the insertion portion 92 including the fixing piece 93 forms a smooth envelope.

[0066] The shape and installation position of the light shielding hood fixing portion 83 of the lens 50 will be described. The light shielding hood fixing portion 83 is a granular protrusion provided on the outer periphery 81 of the lens 50. The light shielding hood fixing portion 83 is formed in a position corresponding to the fixing piece 93 so that it is fixed by fitting with it. In addition, an outer peripheral convex portion 82 is formed along the circumferential direction on the outer periphery 81 of the lens 50. The outer peripheral convex portion 82 is formed below the light shielding hood fixing portion 83 and functions as a stopper against which the lower end of the light shielding hood 90 fitted over the lens 80 abuts. As shown in FIG. 10 , in a radial cross section, the light shielding hood fixing portion 83 has a shape that is closer to vertical at the upper part than at the lower part, with the largest protrusion sandwiched between them.

[0067] The shapes and installation positions of the rotation restricting recess 84 and the rotation restricting protrusion 96 will be described. The lens 80 and the light-shielding hood 90 are provided with the rotation restricting recess 84 and the rotation restricting protrusion 96 as rotation load receiving portions for receiving the rotation load of the light-shielding hood 90 on the lens 80. The rotation restricting protrusion 96 is a substantially rectangular portion formed to protrude downward from the lower end of the insertion portion 92. The outer peripheral surface of the rotation restricting protrusion 96 is smoothly continuous with the outer peripheral surface of the insertion portion 92. The rotation restricting recess 84 is a recess provided in the outer peripheral protrusion 82 to accommodate the rotation restricting protrusion 96.

[0068] The light shielding hood 90 is detachably attached to the lens 80 by pressing from above (in the second embodiment, there is no rotational action as in the first embodiment). The light shielding hood 90 is brought close to the lens 80 from above so that the positions of the fixing pieces 93 (attachment parts) provided on the light shielding hood 90 and the light shielding hood fixing parts 83 provided on the outer periphery 81 of the lens 80 correspond to each other.

[0069] The lower frame portion of the fixing piece 93 (mounting portion) then abuts against the upper portion of the shading hood fixing portion 83. By pressing the shading hood 90 further downward toward the lens 80, the lower portion of the fixing piece 93 (mounting portion) climbs over the protruding shading hood fixing portion 83, and the shading hood 90 can be attached. At this time, the opening 95 surrounds and holds the shading hood fixing portion 83, making it possible to prevent the shading hood 90 from falling off the lens 80.

[0070] As described above, the cross section of the shading hood fixing portion 83 is closer to vertical at the upper side than at the lower side where the protrusion is at its maximum. This shape allows the shading hood 90 to be attached to the lens 80 with a relatively small load. However, because the lower side of the convex portion is more horizontal, a relatively large load is required to remove the shading hood 90. This shape effectively prevents unintentional detachment. Furthermore, by appropriately changing the angle of inclination at the upper and lower sides of the maximum protrusion, it is possible to appropriately adjust the ease of attachment and detachment, including the prevention of unintentional detachment.

[0071] Since notches 94 that form gaps are provided on both sides of the fixing piece 93, when the lower frame of the fixing piece 93 climbs over the hood fixing part 83 during installation of the shading hood 90, the fixing piece 93 is more likely to elastically deform, allowing the shading hood 90 to be installed with an appropriate load. In addition, by appropriately adjusting the width and length of the notches 94, it is possible to control the ease of installation and removal.

[0072] In this embodiment, the rotation-direction load can be borne by the rotation-restricting recess 84 and the rotation-restricting protrusion 96. As described above, when the light-shielding hood fixing portion 83 and the fixing piece 93 are combined to form a fitting structure, the rotation-restricting recess 84 receives the rotation-restricting protrusion 96. At this time, the light-shielding hood 90 and the lens 80 are smoothly received, but relative rotation in the radial direction between the light-shielding hood 90 and the lens 80 is substantially restricted. With this configuration, the rotation-direction load is borne by the rotation-restricting recess 84 and the rotation-restricting protrusion 96, so that the light-shielding hood fixing portion 83 and the fixing piece 93 are less likely to receive the rotational load, leading to improved reliability.

[0073] The present disclosure is further described by the following embodiments. Configuration 1: An LED lamp detachably attached to a socket, the LED lamp comprising: a light source unit including an LED element; a circuit for supplying power to the light source unit; a lens for controlling light emitted from the light source unit; a cylindrical outer cover with a bottom that houses the light source unit, the circuit, and the lens; a base pin protruding from the outer cover and electrically connected to the circuit; and a cylindrical light-shielding hood including a light-shielding portion extending from an opening in the outer cover and an insertion portion inserted into the cylindrical outer cover. Configuration 2: The LED lamp according to Configuration 1, wherein the light-shielding hood is detachably attached. Configuration 3: The LED lamp according to Configuration 2, wherein an attachment portion provided on the light-shielding hood is fitted with a light-shielding hood fixing portion provided on the lens, thereby detachably attaching the light-shielding hood to the lens. Configuration 4: In the LED lamp described in any one of configurations 1 to 3, the insertion portion of the light-shielding hood is configured to abut against the inner circumferential surface of the outer cover when a force is applied at least in the radial direction of the light-shielding hood. Configuration 5: In the LED lamp described in any one of configurations 1 to 4, the light-shielding hood and the lens are coupled to each other by rotating them relatively. Configuration 6: In the LED lamp described in configuration 5, the lens and the light-shielding hood are provided with rotation restricting portions that restrict rotation in the direction opposite to the rotation direction when the light-shielding hood is attached to the lens. Configuration 7: In the LED lamp described in any one of configurations 1 to 4, the light-shielding hood and the lens are coupled to each other by inserting the lens into the tube of the light-shielding hood and applying an axial load. Configuration 8: In the LED lamp described in configuration 7, the lens and the light-shielding hood are provided with separation restricting portions that prevent the light-shielding hood from separating axially from the lens. Configuration 9: In the LED lamp according to any one of configurations 1 to 8, the lens and the light-shielding hood are provided with a rotational load receiving portion for receiving a rotational load of the light-shielding hood applied to the lens.

[0074] REFERENCE SIGNS LIST 1 LED lamp 2 LED module 10 Outer cover 11 Large diameter portion 12 Small diameter portion 12a Through hole 13 Convex portion 13a Protrusion 15 Base pin 20 Light source portion 21 LED element 22 Substrate 25 Heat sink 26 Base portion 26b Wiring insertion hole 27 Cylinder wall 30 Circuit 31 Circuit board 32 Circuit component 35 Circuit holder 36 Substrate fixing portion 37 Base pin fixing portion 39 Flange 40 Holder 42 Cylinder wall 43 Opening 44 Concave portion 45 Locking hole 49 Adhesive 50 Lens 52 Emission surface 52a First region 52b Second region 53 Protrusion 54 Outer periphery 55 Outer periphery convex portion 60a, 60b Light-shielding hood fixing portion 61a, 61b Concave portion 62a, 62b Restricting protrusions 70 Light-shielding hood 71 Light-shielding portion 72 Insertion portion 73a, 73b Engaging protrusions 74a Claws 80 Lens 81 Outer periphery 82 Outer periphery convex portion 83 Light-shielding hood fixing portion 84 Rotation-restricting recess 90 Light-shielding hood 91 Light-shielding portion 92 Insertion portion 93 Fixing piece 94 Notch 95 Opening 96 Rotation-restricting convex portion 100 Connector 101 Socket 102 Plug 103 Shaft 104 Wiring duct rail

Claims

1. An LED lamp detachable from a socket, comprising: a light source unit including an LED element; a circuit for supplying power to the light source unit; a lens for controlling light emitted from the light source unit; a bottomed cylindrical outer cover for housing the light source unit, the circuit, and the lens; a base pin protruding from the outer cover and electrically connected to the circuit; and a cylindrical light-shielding hood including a light-shielding portion extending from an opening of the outer cover and an insertion portion inserted into the cylinder of the outer cover.

2. The LED lamp according to claim 1, wherein the light-shielding hood is detachably attached.

3. The LED lamp according to claim 2, wherein the light-shielding hood is detachably attached to the lens by fitting a mounting portion provided on the light-shielding hood and a light-shielding hood fixing portion provided on the lens.

4. The LED lamp according to claim 1 or 2, wherein the insertion portion of the light-shielding hood is configured to contact the inner peripheral surface of the outer cover when a force acts at least in the radial direction of the light-shielding hood.

5. The LED lamp according to claim 3, wherein the light-shielding hood and the lens are coupled to each other by relatively rotating them.

6. The LED lamp according to claim 5, wherein the lens and the light-shielding hood are provided with a rotation restricting portion for restricting rotation in a direction opposite to the rotation direction when the light-shielding hood is attached to the lens.

7. The LED lamp according to claim 3, wherein the light-shielding hood and the lens are coupled by inserting the lens into the cylinder of the light-shielding hood and applying an axial load.

8. The LED lamp according to claim 7, wherein the lens and the light-shielding hood are provided with a detachment restricting portion for suppressing axial detachment of the light-shielding hood from the lens.

9. The LED lamp according to claim 7, wherein the lens and the light-shielding hood are provided with a rotation load receiving portion for receiving a rotation load of the light-shielding hood with respect to the lens.

Images