JP6178773B2 - LED lamp and lens for LED lamp - Google Patents

Description

  The present invention relates to an LED lamp whose light emission shape is similar to a filament, and an LED lamp lens used therefor.

  Conventionally, an incandescent bulb using a filament is generally used as a lighting fixture (Patent Document 1). This incandescent bulb has a horizontally elongated rectangular light emission shape by light emission from a filament installed between a pair of left and right stems.

  By the way, light-emitting diodes (hereinafter referred to as “LEDs”), which have lower power consumption and longer life than conventional incandescent bulbs, are becoming one of the energy-saving measures along with the growing ecological awareness of consumers. The range of use is rapidly widening, and there is an increasing demand to use LED lamps incorporating LEDs as an alternative to incandescent lamps.

Japanese Patent Laying-Open No. 2005-276556 (FIG. 1)

  In lighting fixtures that are higher than the line of sight, such as ceiling lighting, there are few opportunities for the light source to be in contact with the eyes, so even if the incandescent light bulb is replaced with an LED lamp, no particular problem occurs.

  However, in lighting fixtures where the light source often touches directly, such as floor lights, when LED lamps are used instead of incandescent bulbs, long and familiar filaments (incandescent bulbs) and round or square A small chip-like LED (LED lamp) has a completely different light emission shape, and thus has a problem of causing a visual discomfort due to a difference in the light emission shape.

  Of course, if a plurality of chip-like LEDs are used and arranged in a line according to the shape of the filament, a horizontally long light emission shape like a filament can be obtained, but from the viewpoint of energy saving measures, power consumption is reduced. Even if it is low, it is not preferable to use a plurality of LEDs.

  The present invention has been made to solve such a problem. The light emitting shape can be made to resemble the filament of an incandescent light bulb even though only one LED is used. The development of an LED lamp that does not cause the problem and a lens used therefor is an issue.

The invention described in claim 1 includes: a light receiving surface 14c that receives light and a lens body 14a that is disposed opposite to the light receiving surface 14c and has a horizontally long lens body 14a having a front surface 14e that emits the light; The elongated portion 14m extending in the longitudinal direction of 14a is formed in a wedge shape that becomes gradually narrower toward the tip, and the incident light is reflected to the lens body 14a at a position facing the light receiving surface 14c on the front surface 14e. A reflective recess 14f is formed , all or part of the outer peripheral edge of the front surface 14e is chamfered, and the front side chamfer 14g is inclined with respect to the front surface 14e. " This is a lens 14 for 10.

  The lens 14 receives light from the light receiving surface 14c, and the light reflected by the reflecting recess 14f repeats countless reflections within the lens body 14a, and then exits from the entire surface including the reflecting recess 14f. Here, the laterally long in plan view means a state in which the elongated portion 14m extends from both the center portion 14o of the lens body 14a to both sides like a wing. For example, "rectangular" It is. A light receiving surface 14c is formed on the back surface of the central portion 14o, and a reflective recess 14f is formed on the front surface. Then, the thickness between the front surface 14e on the front surface side of the extended portion 14m and the back surface 14d, which is the back surface thereof, gradually becomes thinner and wedged toward the tip of the extended portion 14m (FIG. 13). By doing so, light reaches the tip of the elongated portion 14m, and in particular, the uniformity of the light emitted from the lens body 14a is increased. The shape of the reflective recess 14f is not particularly limited, but is formed in a “conical shape”, a “pyramidal shape”, or a “hemispherical shape” at a depth from the front surface 14e to the light receiving surface 14c or the vicinity thereof.

The "all or part of the outer peripheral edge of the front surface 14e is chamfered, the front chamfered portion 14g is because it is inclined to the front surface 14e, the front chamfered portion 14g in the bright shining lens body 14a of the light The direction of exit changes and this part is emphasized, creating an atmosphere as if the “filament” is shining. In the above, the “part” of the front side chamfer 14g means a shape in which the long side portion of the front surface 14e is chamfered as shown in FIGS. It is a shape like that. This portion is referred to as a front side surface taking portion 14g.

The invention described in claim 2 is characterized in that “a satin-like unevenness is formed on the whole or a part of the lens body 14a”. By doing in this way, light is scattered more by this unevenness | corrugation, and the uniformity degree of the light emitted from the lens main body 14a increases.

The invention described in claim 3 is described as follows. “Surface emitting LED 12, lens 14 described in claim 1 or 2 , wherein the surface emitting LED 12 is provided facing the light receiving surface 14 c, and The LED lamp 10 includes a power supply unit 22 for supplying power to the LED 12.

The invention described in claim 4 is the LED lamp 10 characterized in that “the cover 16 covering the lens 14 is further provided”. In addition, when the surface of the cover 16 is made into a satin finish (ground glass shape), the lens 14 is not directly visible from the outside, and the entire cover 16 shines brightly and dimly, resulting in a conventional ground glass incandescent bulb.

  According to the present invention, the light received as described above is reflected by the reflection recess 14f, and is repeatedly emitted innumerably within the lens body 14a to be emitted, and the entire lens body 14a is illuminated. And the light which entered the extension part 14m in it advances to the front-end | tip, repeating countless reflection inside this extension part 14m. At this time, since the elongated portion 14m extending in the longitudinal direction of the lens body 14a is formed in a wedge shape that becomes gradually narrower toward the tip, light reaches the tip of the elongated portion 14m even if the amount of light gradually decreases due to light emission. To do. As a result, the entire horizontally long lens body 14a shines uniformly. In other words, the light emission shape can be a horizontally long shape such as a filament, even though one LED 10 is used. Therefore, by incorporating this lens 14 in the LED lamp 10, an incandescent lamp can be substituted. Even when it is used as a light source, it does not cause a sense of incongruity during light emission.

It is sectional drawing which shows the LED lamp of one Example of this invention. It is a front view which shows the lens used for FIG. FIG. 3 is a plan view of the lens of FIG. 2. 2 is a side view showing the lens. FIG. 4 is a cross-sectional view taken along line A-A ′ in FIG. 3. FIG. 4 is a B-B ′ sectional view in FIG. 3. It is a top view of the 2nd Example of FIG. FIG. 4 is a plan view of the third embodiment of FIG. 3. It is a front view which shows the other Example of the lens of this invention. FIG. 10 is a plan view of the embodiment of FIG. 9. FIG. 10 is a side view of the embodiment of FIG. 9. It is C-C 'sectional drawing in FIG. It is a perspective view of the basic form of the present invention.

  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 generally includes a surface emitting LED 12, a lens 14, a cover 16 provided as necessary, a base 18 constituting the lamp body 11, a base 20, and a power supply. And means 22.

  The LED 12 is a semiconductor element that emits light when a predetermined voltage is applied, and one LED 12 is mounted and held at the center of the upper surface of a base 18 to be described later.

  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.

  The lens 14 is a transparent solid body made of glass or resin. As shown in FIGS. 2 to 13, the lens 14 is roughly composed of a lens body 14 a and a mounting portion 14 b. The material of the lens 14 that is an integral part of the mounting portion 14b and the lens body 14a is not limited to the above-described transparent body as long as it can transmit light. Also good. And the said shape shown in FIG. 13 is a basic shape of this invention, FIGS. 2-8 is the 1st Example and its modification, and FIGS. 9-12 is 2nd Example. Hereinafter, the first embodiment will be described with reference to FIG. 13 and FIGS.

  The lens body 14a is horizontally long in plan view, that is, "rectangular (Fig. 13)" "horizontal hexagon (not shown) or octagon (Figs. 3, 7 and 8)" or "diamond (not shown) in plan view. The extending portion 14m extends from both the central portion 14o of the lens body 14a to both sides like a wing. The light receiving surface 14c provided at the center of the back surface of the lens body 14a, the back surface 14d extending laterally on both the left and right sides of the light receiving surface 14c, and continuing to the light receiving surface 14c, and the front surfaces of the light receiving surface 14c and the back surface 14d. And a provided front surface 14e.

  An elongated portion 14m extending in the longitudinal direction on both sides from the central portion 14o of the lens body 14a provided with the light receiving surface 14c, which is a portion between the front surface 14e and the back surface 14d of the lens body 14a, has a thickness toward the tip. It is formed in a wedge shape that gradually decreases (FIG. 13). On the other hand, in the case of FIG. 3 and other plan view horizontally long octagons, the elongated portion 14m is formed so as to gradually reduce its width W toward the distal end direction.

  The case of FIG. 3 is an example in which a front side chamfer 14g having the same width and inclined with respect to the front surface 14e is formed on the entire circumference of the front surface 14e. On the other hand, in FIGS. 7 and 8, the front surface 14e is a narrow rectangle, and the front side chamfer 14g is formed in a trapezoidal shape in plan view on both sides thereof.

  In the case of FIG. 13, the entire back surface 14d is a flat surface. However, in FIGS. 3, 7 and 8, as with the light emitting front surface 14e, the back surface 14d is inclined on both sides of the back surface 14d. In addition, many reflecting surfaces are formed on the entire lens body 14a.

As described above, the position of the front surface 14e facing the light receiving surface 14c (the front surface of the central portion 14o) is not particularly limited, but in this embodiment, the light emitting front surface 14e reaches the light receiving surface 14c or the vicinity thereof. A reflective conical recess 14f having a depth of “cone” is formed. Of course,
It may be “pyramidal” or “hemispherical”. When the reflection recess 14f is “conical”, the inner angle θ is preferably set in a range of 75 ° ≦ θ ≦ 105 °, and vertically incident light is reflected horizontally in the circumferential direction. Thus, in this embodiment, it is set to 90 °.

  A cylindrical (or ring) mounting portion 14b is integrally provided on the back side of the central portion 14o of the lens body 14a, and the space surrounded by the mounting portion 14b and the light receiving surface 14c accommodates the LED 12. The LED housing space 14h. The light receiving surface 14c may be a flat end surface, or a plurality of shallow V-shaped grooves may be formed in parallel at a right angle to the longitudinal direction of the lens body 14a so that incident light is easily diffused. However, conical minute irregularities may be formed. The pointed bottom of the reflective recess 14f coincides with the center of the LED 12 housed in the LED housing space 14h.

  A pair of downwardly extending attachment pieces 14i are respectively provided on the side surface of the attachment portion 14b, and an engagement claw that engages with an engagement recess 24c of the upper base 24 described later at the distal end of each attachment piece 14i. Each of 14j protrudes inward.

  The cover 16 is a hollow spherical member formed of transparent glass, and is disposed on the upper surface of the base 18 as necessary so as to enclose the LED 12 and the lens 14. The material of the cover 16 is not limited to glass as long as it is a transparent body, and may be formed of, for example, a synthetic resin. In the illustrated embodiment, the cover 16 is a transparent body, but it may be formed in a frosted glass shape.

  The lamp body 11 includes a base 18, a base 20, and a power feeding means 22. The base 18 is a member that holds the LED 12, the lens 14, and the cover 16, and that houses a power feeding means 22 that supplies 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 covered rectangular cylinder) formed of a material excellent in heat conduction and heat dissipation such as metal (for example, aluminum) or ceramic. An upper surface recess 24a is formed on the upper surface of the upper base 24, and the lower surface opening of the cover 16 is attached to the inner peripheral surface of the upper surface recess 24a.

  In addition, a columnar support column 24b for supporting the LED 12 and the lens 14 is provided so as to protrude upward at a central portion of the upper surface of the upper base 24 (a central portion of the upper surface recess 24a lowered one step).

  The LED 12 is attached to the central portion of the upper surface of the support pillar 24b, and the lens 14 is attached so as to cover the LED 12 (the LED 12 is housed in the LED housing space 14h described above). In this embodiment, the lens 14 and the support column 24b of the upper base 24 are connected by engaging the engagement claw 14j of the lens 14 with the engagement recess 24c provided on the side surface of the support column 24b.

  The upper base 24 is formed with a lower surface opening recess 24d that opens to the back surface side, and the upper portion of the lower base 26 is inserted into and secured to the lower surface opening recess 24d. The upper base 24 is provided with a communication hole 28 that communicates the upper surface of the support column 24b and the ceiling surface of the lower surface opening recess 24d.

  The lower base 26 is a columnar body made of an insulating material such as ceramic. The lower end portion 26a has a one-step reduced diameter, and a screw is formed on the outer peripheral surface of the lower end portion 26a.

  The outer diameter of the lower base 26 is slightly smaller than the inner diameter of the lower surface opening recess 24d of the upper base 24, and its upper end is fitted into the lower surface opening recess 24d of the upper base 24 as described above. Yes. A hollow portion 26b having an upper surface opening is formed at the center of the lower base 26, and the inner space 30 is formed by cooperation between the hollow portion 26b and the lower surface opening recess 24d of the upper base 24. The power feeding means 22 is arranged in the space 30.

  As described above, a screw is formed on the outer peripheral surface of the lower end portion 26a of the lower base 26, and the base 20 is screwed into this screw.

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

  The drive circuit 22a is disposed in an internal space 30 formed by cooperation of a lower surface opening recess 24d of the upper base 24 and a hollow portion 26b of the lower base 26, and the input-side lead wire 22b is connected to the lower base 26b. 26 is disposed at the lower end side of the hollow portion 26 b in the figure, and the output side lead wire 22 c is inserted into the communication hole 28 of the upper base 24.

  When the LED 12 configured as described above is turned on, the light emitted from the light emitting surface 12a of the LED 12 enters the inside through the light receiving surface 14c of the lens 14. Here, since the reflective recess 14f is formed at a position facing the light receiving surface 14c on the front surface 14e, the light entering the lens 14 from the light receiving surface 14c is reflected thereby.

  The reflected light is emitted from the entire surface of the lens body 14a while being repeatedly reflected innumerably in the lens body 14a. In the extended portion 14m extending in the longitudinal direction of the lens body 14a, the light incident on this portion is emitted from the entire extended portion 14m and proceeds in the distal direction while repeating innumerable reflections therein, but the extended portion Since 14m is wedge-shaped, the amount of light does not fade to the tip, and the light reaches the tip. As a result, a dark part does not occur and the entire lens body 14a shines uniformly. In other words, since the entire horizontally long lens 14 appears to shine, the light emission shape can resemble the horizontally long filament of a conventional incandescent bulb.

  In the present embodiment, the outer peripheral edges of the front surface 14e and the back surface 14d are chamfered, and light is reflected in multiple directions by the front and back side chamfers 14g and 14k. The degree of uniformity increases. At the same time, since the light concentrates on the ridge line portion X of the lens body 14a and this portion emits light strongly, the lens 14 is strongly linear in the whole shining lens body 14a when viewed from any direction. The shining portion is visually recognized, whereby the light emission shape of the lens 14 can be made to look more like a filament.

  In the above-described embodiment, the lens body 14a is formed in a horizontally long octagonal shape in plan view, but any shape can be adopted as long as the light emission shape can be a horizontally long shape such as a filament.

  Further, the whole or a part of the front surface 14e of the lens body 14a (for example, only the reflective recess 14f portion may be used, or only the front side chamfer 14g around the front surface 14e may be used, or the front surface excluding the front side chamfer 14g. 14e may be provided on the upper surface of 14e or a combination thereof. In this case, the light emitted from the front surface 14e is diffused in all directions by the satin-like unevenness, which contributes to improving the uniformity of the lens body 14a. If the cover 16 has a satin finish, the light emitted from the lens 14 can have a softer atmosphere (similar to a conventional pear earth).

  7 and 8 show a case where the front surface 14e is rectangular, and the rectangular front surface 14e is visually recognized in the lens body 14a where the front surface 14e is shining, and the ridgeline portion X is strongly shining. Brings out a luminous form.

  9 to 12 show that the front surface 14e is formed symmetrically (or in a shape close to symmetry) in conformity with the back surface 14d so as to have a lateral V shape when viewed from the front, and is functionally the same as the first embodiment.

  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: back surface, 14e: front surface, 14f: reflection concave 14g: front side surface taking part, 14h: LED housing space, 14i: mounting piece, 14j: engaging claw, 14k: back side surface taking part, 14m: extension part, 14o: center part, 16: cover, 18: base , 20: base, 20a: side surface, 20b: contact, 20c: insulation, 22: power supply means, 22a: drive circuit, 22b: input side lead wire, 22c: output side lead wire, 24: upper base, 24a: Upper surface recess, 24b: support pillar, 24c: engagement recess, 24d: lower surface opening recess, 26: lower base, 26a: lower end, 26b: cavity, 28: communication hole, 30: inner space, W: width , X: Ridge Part.

Claims (4)

A light receiving surface that receives light and a lens body that is disposed opposite to the light receiving surface and has a horizontally long lens body having a front surface that emits the light,
The elongated portion extending in the longitudinal direction of the lens body is formed in a wedge shape gradually becoming narrower toward the tip,
A reflective recess for reflecting the incident light to the lens body is formed at a position facing the light receiving surface on the front surface .
All or part of the outer peripheral edge of the front surface is chamfered,
The lens for LED lamps characterized in that the front side chamfered portion is inclined with respect to the front surface. The lens for LED lamps according to claim 1, wherein a satin-like unevenness is formed on all or part of the lens body . A surface-emitting LED, a lens according to claim 1, 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 that . The LED lamp according to claim 3, further comprising a cover that covers the lens .

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