JP6215177B2 - LED lamp and lens for LED lamp - Google Patents

Description

  TECHNICAL FIELD The present invention relates to an LED lamp suitable for chandelier type lighting whose emission shape resembles a candle flame, and an LED lamp lens used therefor.

  Chandeliers are popular as lighting fixtures that have been used since the Middle Ages, and light sources for chandeliers started in the old days with candles, changed to gas lights, light bulbs, and other technological innovations. For example, Patent Document 1 is known as an example of using an incandescent bulb as a light source for a chandelier.

  Conventional incandescent light bulbs as light sources for chandeliers have only the shape of the envelope covering the light source (filament) resembling the shape of a candle flame, and the light emission shape of the light source (filament) resembles a candle light None were considered.

  However, incandescent light bulbs as conventional light sources for chandeliers have been widely used in place of candles because the red glowing filament can create an antique atmosphere produced by candles to some extent and is safe and convenient (Patent Document 1). .

  Recently, however, as the ecological awareness of consumers, which has been triggered by soaring crude oil prices, as one of the energy-saving measures, light-emitting diodes that have the advantages of lower power consumption and longer life than incandescent bulbs ( Hereinafter, there is an increasing demand for using an LED lamp using “LED” as an alternative to an incandescent bulb, and there is a similar technical demand for a light source for chandeliers. However, unlike the filament, it is extremely artificial light. Therefore, Japanese Patent Application Laid-Open No. 2004-228867 has attempted to solve the problems in using the LED as a light source.

JP-A-10-106512 (page 4, FIG. 2) Special table 2014-522094 gazette

  Patent Document 2 uses an LED, reflects light from the LED with a conical reflector provided above the LED, projects the reflected light onto a teardrop-shaped envelope, and envelopes a ghost image by a halo effect. It is designed to be molded as if it were in the center. That is, this reflected ghost image is provided by a combination of a halo generating diffusing element and a tapered teardrop envelope. In other words, a conical reflector and a tapered teardrop-shaped envelope are required to represent a reflected ghost image that represents a candle flame with an LED, and in particular, if the shape of the envelope changes, the shape of the reflected ghost image Of course, it will change. That is, in this case, the shape of the envelope is limited to a tapered teardrop shape.

  The present invention develops a lens that can express the flame of a candle with only a lens that guides light from the LED, regardless of the shape of the envelope, and an LED lamp suitable for chandelier type illumination using the lens. Is the subject.

According to the first aspect of the present invention, a lens 14 having a lens body 14a having a light receiving surface 14c for receiving light from the LED 12 on one end surface and emitting light from a tip portion 14h provided at a tip portion of the body portion 14e. Because
The body part 14e and the front end part 14h are provided such that the lateral width gradually decreases as they move away from the light receiving surface 14c, and the angle (inner angle) β formed between the outer surface of the front end part 14h and the outer surface of the body part 14e is formed as an obtuse angle. This is a lens 14 for the LED lamp 10.

  The outer shape of the barrel portion 14e of the lens body 14a is substantially wedge-shaped, substantially truncated cone shape, or substantially polygonal truncated cone shape, and the outer shape of the tip portion 14h is substantially wedge-shaped, substantially cone-shaped, or substantially polygonal pyramid shape following the barrel portion 14e.

In the first aspect of the invention, the body portion 14e is formed in a substantially polygonal frustum, and the tip end portion 14h is formed in the same polygonal pyramid having the same surface direction as that of the body portion 14e. The body side surface 14d and the tip end side surface 14s are formed in a concave curved surface (FIG. 8).

  A typical example of the concave curved surface is a shape obtained by cutting a part of a spherical surface, a spheroidal surface, or a cylindrical surface by a plane parallel to the central axis. When the concave curved surface has a shape obtained by cutting a part of the spheroid or cylindrical surface along a plane parallel to the central axis thereof, the central axis is arranged so as to coincide with the longitudinal direction of the trunk side surface 14d of the trunk portion 14e. The image of the LED 12 projected on the concave curved surface is elongated in the vertical direction. Although not shown in the figure, when the central axis is arranged in a direction (lateral direction) perpendicular to the longitudinal direction, it becomes horizontally long. Therefore, in order to imitate this image with the red burning core of a candle flame, it is preferable to arrange the central axis of the concave curved surface in the longitudinal direction. Note that the distal end side surface 14s of the distal end portion 14h may be formed in the same concave curved surface. As a result, an elongated image of the LED 12 can be formed on the side surface 14s of the distal end portion 14h.

The invention described in claim 2 is characterized in that, in claim 1 , the inclined surface of the tip end portion 14h is chamfered. In this case, the tip end portion 14h is formed in a polygonal shape from the body portion 14e.

According to a third aspect of the present invention, in the first aspect , the lens main body 14a is a polygon having an even plane cross-sectional shape, a pair of front and back body side surfaces 14d facing each other, and a tip continuous with the body side surface 14d. Only the part side surface 14s is formed into a vertically long concave curved surface 14m (FIGS. 2 and 3).

In the invention described in claim 4 , a light receiving surface 14c that receives light from the LED 12 is formed on one end surface, and a lens 14 that has a lens body 14a that emits light from a distal end portion 14h provided at the distal end portion of the body portion 14e. The body portion 14e and the tip portion 14h are provided such that the lateral width gradually decreases as they move away from the light receiving surface 14c, and the angle (inner angle) β between the outer surface of the tip portion 14h and the outer surface of the barrel portion 14e is an obtuse angle. The body portion 14e is formed in a truncated cone shape, the tip end portion 14h is formed in a cone shape, and the front and back opposite side surfaces from the barrel portion 14e to the tip end portion 14h are along the center line of the lens body 14a. It is cut into a concave curved surface extending in the longitudinal direction, and the cut surfaces are formed as a pair of vertically long concave curved surfaces 14m on both front and back surfaces of the lens body 14a (FIG. 2). 3).

  In this case, the outer edge of the vertically concave curved surface 14m (parabolic outline ridge line 14r) shines to simulate a large flame of a candle, and an image of the LED 12 simulating the state where the core is burning red is formed on the top of the vertically concave curved surface 14m. Thus, the external appearance of the lens body 14a becomes closer to the flame of the candle.

The invention described in claim 5 is as follows: “The lens 14 according to any one of claims 1 to 4 , wherein the surface-emitting LED 12 and the surface-emitting LED 12 are provided to face the light receiving surface 14 c. And an electric power supply means 22 for supplying electric power to the LED 12 ”.

The invention described in claim 6 is the LED lamp 10 characterized in that “the envelope 16 covering the lens 14 is further provided”.

  According to the present invention, the light that has entered the lens body 14a from the light receiving surface 14c travels in the distal direction while being totally reflected in the lens body 14a, and gathers at the distal end portion 14h so that the entire distal end portion 14h passes through the body 14e. Make it glow more intensely. This appearance looks like a burning candle flame from a distance. If the chamfered surface of the tip portion 14h is chamfered, this is further emphasized.

  Further, as shown in FIG. 8, if the body side surface 14d or the body side surface 14d and the tip side surface 14s are formed in a concave curved surface, a pair of opposing body side surfaces as shown in FIGS. 14d and the tip side surface 14s connected to the body side surface 14d are formed as one vertically long concave curved surface 14m, the image of the LED 12 is projected on the long concave curved surface 14m in an elongated manner, as if the candle core It appears to be burning red and can more closely approximate a candle flame. If the lens 14 and the LED 12 are used, the LED lamp 10 having a light emitting shape like a candle flame can be provided.

It is sectional drawing which shows the LED lamp of one Example of this invention. It is an enlarged front view of the lens of FIG. FIG. 3 is a plan view of FIG. 2. It is a trunk | drum side view of FIG. FIG. 5 is a cross-sectional view showing the cross section of FIG. 4 and how the light from the LED enters the lens. (A)-(E) are the A-A 'line cutting part end views in FIG. It is sectional drawing which shows the cross section of the other example of FIG. It is a perspective view of the other Example of this invention. It is a perspective view of the further another Example of this invention. It is a drawing substitute photograph which shows the state which turned on the LED lamp of FIG.

  An LED lamp 10 to which the present invention is applied will be described with reference to the drawings. As shown in FIG. 1, the LED lamp 10 is roughly composed of a surface-emitting LED 12, a lens 14, an envelope 16 provided as necessary, a base 18 and a base 20, and a lamp body 11. It is comprised with the electric power feeding means 22.

  The LED 12 is a semiconductor element that emits light when a predetermined voltage is applied, and is mounted and held at the center of the upper surface of a base 18 described later. The light emission color of the LED 12 may be any number of colors, but in the present invention, red is selected because it simulates the flame of a candle.

  The LED 12 in this embodiment is of a type that emits light on a light emitting surface 12a having a square shape in plan view (of course, may be circular), and its light distribution pattern is a so-called Lambertian type. This Lambertian light distribution pattern is characterized by having a distribution of, for example, rugby spherical light, in which most of the light is gathered in the vicinity of the optical axis (= 0 °), and the angle formed with the optical axis is 50% of the total light emitted from the LED 12 is included within the range of ± 30 °, 70% of the total light is included within the range of ± 45 °, and further within the range of ± 60 °. Contains 90% of the total light.

Lens 14 is a transparent solid body made of glass or resin, and the lens main body 14a as shown in FIGS. 2 to 4, the bottom surface of the lens body 14a cylinder (or ring) shaped receiving surface 14 c is integrally This is roughly constituted by the provided mounting portion 14b. And the space enclosed by the attaching part 14b and the light-receiving surface 14c becomes the LED accommodating space 14j for accommodating LED12. In the present invention, the shape shown in FIG. 9 is one basic shape of the present invention (first embodiment), FIG. 8 is an example of a modification of the first embodiment, and FIGS. 2 to 5 are the second embodiment. (Embodiment) FIG. 7 is a cross-sectional view of a modification of the second embodiment. In the following, description will be made with reference to FIG . 9 which is a basic form (first embodiment) with reference to other drawings .

  The lens body 14a of FIG. 9 has a light receiving surface 14c that receives light from the LED 12 on one end surface, a barrel portion 14e having a truncated cone, and a tip portion 14h provided on the tip side of the barrel portion 14e having a conical shape. Has been. Although not shown, a truncated pyramid (for example, a triangular truncated pyramid, a quadrangular truncated pyramid or other polygonal pyramid) may be used instead of a truncated cone, and a truncated pyramid (for example, a triangular, pyramid or other truncated pyramid) may be used instead of a cone. When the body part 14e is a polygonal frustum, the body part side surface 14d of the body part 14e and the front end part side surface 14s of the front end part 14h are formed in the same surface direction so as to be connected in a row (that is, to form one surface). Has been. In this case, both side surfaces 14d and 14s are flat surfaces.

  An angle (inner angle) γ formed with respect to the light receiving surface 14c of the body side surface 14d of the body 14e has an acute inclination close to 90 °. The inner angle β of the tip side surface 14s with respect to the body side surface 14d is larger than the inner angle γ and is an obtuse angle in the range of 135 ° ± 20 °. The intersection angle α between the tip end side surfaces 14s is an acute angle in the range of 90 ° ± 10 °.

  The envelope 16 is a hollow, vertically long spherical (teardrop-shaped) member formed of transparent glass, and is disposed on the upper surface of the base 18 as needed so as to enclose the LED 12 and the lens 14. The material of the envelope 16 is not limited to glass as long as it is a transparent body, and may be formed of synthetic resin, for example.

  The base 18 is a member that holds the LED 12, the lens 14, and the envelope 16, and that houses therein a power supply means 22 that supplies electric power from the outside to the LED 12, and includes an upper base 24 and a lower base 26. ing.

  The upper base 24 is a covered cylindrical body (of course, may be a rectangular tube) formed of a material excellent in heat conduction and heat dissipation such as metal (for example, aluminum) or ceramic. A shallow recess 24a is formed on the upper surface of the upper base 24, the LED 12 is mounted in the center of the recess 24a, and the lower surface opening of the envelope 16 is attached to the inner peripheral surface of the recess 24a. .

  A cylindrical insertion portion 24b is suspended from the lower surface of the upper base 24, and a male screw 24c is screwed to the outer surface of the insertion portion 24b. A recess 24d provided inside the insertion portion 24b forms an internal space 30 in cooperation with a recess 26c of the lower base 26 described later. The upper base 24 is provided with a communication hole 28 that communicates the upper surface (the bottom surface of the recess 24a) and the lower surface (the ceiling surface of the recess 24a).

  The lower base 26 is made of an insulating material such as ceramic, and is a different-diameter columnar body composed of a large diameter portion 26a and a small diameter portion 26b.

  The outer diameter of the large-diameter portion 26a is formed to be approximately equal to the outer diameter of the upper base 24, and a recess 26c is formed at the center thereof. As described above, the recess 26 c and the recess 24 d of the upper base 24 cooperate to form the internal space 30, and the power feeding means 22 is disposed in the internal space 30.

  A female screw 26d is engraved on the stepped portion formed in the upper portion of the recess 26c. Then, the male screw 24c of the insertion portion 24b of the upper base 24 is screwed to the female screw 26d, whereby the upper base 24 and the lower base 26 are integrated.

  A screw is formed on the outer peripheral surface of the small diameter portion 26b, and the base 20 is screwed into the screw.

  The base 20 is a bottomed cylindrical body that is screwed into a socket (not shown) such as a lighting fixture, and a body side surface portion 20a made of a conductive material (for example, metal) on which a screw is formed. The protrusion 20b is made of a material and protrudes from the bottom, and the insulating portion 20c made of an insulating material that electrically insulates between the body side surface 20a and the protrusion 20b.

  The power feeding means 22 is for supplying the power supplied to the base 20 to the LED 12, transforms the voltage applied to the base 20 to the drive voltage of the LED 12, and an excessive current flows to the LED 12. The driving circuit 22a is configured to include a pair of input-side lead wires 22b that conducts between the base 20 and the driving circuit 22a, and a pair of output-side lead wires 22c that conducts between the driving circuit 22a and the LED 12.

  Further, as described above, the drive circuit 22a is disposed in the internal space 30 formed by cooperation of the recess 24d of the upper base 24 and the recess 26c of the lower base 26, and the input side lead wire 22 b is disposed on the lower end side of the recess 26 c of the lower base 26 in the figure, and the output side lead wire 22 c is inserted through the communication hole 28 of the upper base 24.

  Thus, when the LED 12 is turned on, the light incident on the lens body 14a from the LED 12 is almost totally reflected by the barrel side surface 14d in the barrel portion 14e and proceeds in the distal direction, and the light emitted from the barrel portion 14e is very small. The light traveling in the tip direction while repeating internal reflection in the body portion 14e gathers at the tip portion 14h and strongly shines the entire tip. As a result, the lens body 14a has an appearance like a flame of a candle, similar to the tip of a flame in which the light from the LED 12 is emitted more strongly from the tip portion 14h than the barrel portion 14e and the tip portion 14h glows red. When the plane cross section of the lens body 14a is polygonal, the ridgeline is shining strongly in addition to the above, and depending on the viewing direction, this ridgeline looks like a shape imitating the outer edge of the flame.

FIG. 8, which is an example of a modification of the first embodiment, has a barrel portion 14e having a quadrangular pyramid and a tip portion 14h having a quadrangular pyramid, and its barrel side surface 14d and tip portion side surface 14s are vertically long concave curved surfaces. In this example, the central axis of the curved surface is formed in a direction along the central axis of the lens body 14a. The concave curved surface is as described above. The shapes of the trunk portion 14e and the tip portion 14h are not limited to a quadrangle as described above. The behavior of light due to the lighting of the LED 12 is basically the same as that of the first embodiment, but due to the relationship that the trunk portion 14e is a quadrangular pyramid and the trunk side surface 14d is a vertically long concave curved surface , each trunk side surface 14d. An image Z of the vertically elongated LED 12 as shown in FIG. Since the distal end side surface 14s of the distal end portion 14h is also a concave curved surface, an image of the LED 12 that is vertically elongated corresponding to the curved surface is reflected.

  In the above example, it is a vertically long concave curved surface, but it may be a horizontally long concave curved surface or a spherical surface. In the case of a horizontally long concave curved surface, a horizontally long elliptic image appears on each of the body side surfaces 14d and 14s, and in the case of a spherical surface, it is circular. The image of will appear.

Further, in the modification of the first embodiment, the barrel portion side face 14d, but the tip portion side surface 14s showed the case of the concave surface, may be planar (not shown) or opposite the convex curved surface (FIG. 6 D). In that case, not appear elongated or rounded image of LED12 on both sides 14d · 14 s, consisting only of the lens 14 across the tip portion 14h shines strongly as shown in the first embodiment. Further, any in the above embodiment, both side surfaces 14d · 14 s showed when formed into a curved surface to form only the barrel portion side face 14d of the barrel portion 14e on the curved surface, the tip portion 14h tip side 14 s may be formed in a plane.

  A second embodiment shown in FIGS. 2 to 5 will be described. In the second embodiment, the body portion 14e of the lens body 14a is formed in a truncated cone shape, the tip portion 14h is formed in a cone shape, and the front and back opposite side surfaces of the lens body 14a extend from the body portion 14e to the tip portion 14h. A concave curved surface extending in the longitudinal direction along the center line is cut out, and a pair of longitudinal concave curved surfaces 14m are formed on both the front and back surfaces of the lens body 14a. The vertically long concave curved surfaces 14m on the front and back surfaces extend from the proximal end surface of the body portion 14e to the distal end of the distal end portion 14h, and coincide at the distal end. Therefore, the truncated cone curved surface remains on both sides of the vertically long concave curved surface 14m of the body portion 14e. This portion is defined as a convexly curved body side surface 14f. The outer ridge line 14r on the surface of the body part 14e of the vertically long concave curved surface 14m is substantially a parabola. On the other hand, the frustoconical curved surface is chamfered on both sides of the tip portion 14h of the vertically long concave curved surface 14m, the cross section of this portion is formed in a V shape, and the tip portion 14h is formed like a double-edged blade tip. This chamfered portion is referred to as a tip chamfered portion 14t. A horizontal surface is formed by the chamfering at the boundary between the body portion 14e and the tip portion 14h. This horizontal plane is 14n. Inner angles α to γ at the body 14e, the convexly curved body side surface 14f, and the tip 14h of the lens body 14a are the same as in the first embodiment.

  Then, when the LED 12 is turned on and light enters the lens body 14a from the LED 12, the light from the portion 14f is almost totally reflected at the side 14f of the convex body at the body 14e as in the first embodiment. Are only a few due to diffuse reflection. Similarly, although the longitudinal concave curved surface 14m has a smaller inner angle δ with respect to the light receiving surface 14c than the convex curved body side surface 14f, the light is totally reflected on this surface as well, and the emitted light is also small. However, since the outer edge line of the convex curved body side surface 14f (the outer shape ridge line 14r of the vertically long concave curved surface 14m) has a corner, this portion shines strongly in a substantially parabolic shape. Most of the light travels in the distal direction while repeating internal reflection in the body portion 14e, gathers at the distal end portion 14h, and strongly shines the entire distal end portion 14h. In particular, the triangular tip chamfered portion 14t of the tip portion 14h shines intensively. Then, an image of the vertically long and narrow red LED 12 formed by reflection is formed on the upper part of the vertically concave curved surface 14m. As a result, the contoured edge 14r of the vertically concave curved surface 14m that is substantially parabolic and glows red looks like a large flame of a candle, and the red glowing portion of the triangular chamfer 14t of the tip portion 14h burns red. The image of the above-described vertically long and long red LED 12 looks as if the candle core is burning, and the lens body 14a alone has the appearance of a burning candle that has never been seen before.

Further, by using the envelope 16 of the elongated spheres (teardrop), light exiting from the lens 14, reflected on the envelope 16 of the elongated spheroids like appearance candle flame as shown in FIG. 10 In addition, it can create an antique atmosphere like the light of a real candle. Of course, as described above, the lens 14 alone can create an antique atmosphere like candlelight. Therefore, the shape of the envelope 16 is secondary.

  In addition, if the light emission color of the LED 12, the color of the lens 14 and the color of the envelope 16 are, for example, orange, it can be made closer to the flame of a candle.

10: LED lamp, 11: lamp body, 12: LED, 12a: light emitting surface, 14: lens, 14a: lens body, 14b: mounting portion, 14c: light receiving surface, 14d: body side surface, 14e: body portion, 14f : Convex curved body side surface, 14h: tip portion, 14j : LED housing space, 14m: vertically long concave curved surface, 14n: horizontal surface, 14r: external ridge line, 14s: tip side surface, 14t: tip chamfered portion, 16: envelope , 18: base, 20: base, 20a: trunk side surface, 20b: protruding portion, 20c: insulating portion, 22: power supply means, 22a: drive circuit, 22b: input side lead wire, 22c: output side lead wire 24: upper base, 24a: recess, 24b: insertion part, 24c: male screw, 24d: recess, 26: lower base, 26a: large diameter part, 26b: small diameter part, 26c: recess, 26d: Female screw, 2 8: Communication hole, 30: Internal space, α, β, γ, δ: Interior angle , Z: Image of LED 12 .

Claims (6)

A light-receiving surface that receives light from the LED is formed on one end surface, and a lens having a lens body that emits light from a tip portion provided at a tip portion of the body portion,
The body part and the tip part are provided so that the lateral width gradually decreases as the distance from the light receiving surface increases, and the angle formed by the outer surface of the tip part and the outer surface of the body part is formed as an obtuse angle,
The barrel portion is formed in a substantially polygonal frustum, the tip portion is formed in the same polygonal pyramid with the same surface direction as the barrel portion, and the barrel side surface or the barrel side surface and the tip side surface are concave curved surfaces. A lens for an LED lamp, which is formed . Lens for LED lamp according to claim 1, characterized in that chamfered inclined surface of the tip portion is such. Flat sectional shape even polygonal lens body, claim 1, and a pair of front and rear barrel portion side opposing, characterized in that only the tip portion side surface continuous to the barrel portion side face is formed in a vertically concave curved surface The lens for LED lamps described in 1. A light-receiving surface that receives light from the LED is formed on one end surface, and a lens having a lens body that emits light from a tip portion provided at a tip portion of the body portion,
The body part and the tip part are provided so that the lateral width gradually decreases as the distance from the light receiving surface increases, and the angle formed by the outer surface of the tip part and the outer surface of the body part is formed as an obtuse angle,
A concave curved surface in which the barrel portion is formed in a truncated cone shape, the tip portion is formed in a cone shape, and the front and back opposing side surfaces extend in the longitudinal direction along the center line of the lens body from the barrel portion to the tip portion. It is excised Jo, L ED lens for a lamp you characterized in that該切dividing surface is formed as a pair of elongated concave surfaces on both sides of the lens body. A surface-emitting LED, the lens according to any one of claims 1 to 4, wherein the surface-emitting LED is provided to face a light-receiving surface, and a power supply unit for supplying power to the LED. An LED lamp characterized by comprising . L ED lamp of claim 5 that you said envelope covering the lens is further provided.