[Title of Invention]
LAMP
[Technical Field]
[OOOl]
The present invention is related to lamps using light-emitting elements such
as LEDs as a light source.
[Background Art]
[0002]
LEDs are a type of semiconductor light-emitting element. With a view to
energy conservation, in recent years a lamp (hereafter, "LED lamp") using LEDs as
a light source has been proposed as a bulb-type lamp that is an alternative to an
incandescent light bulb.
[0003]
The LED lamp includes a plurality of LEDs, a mounting board, a case that
is cylindrically shaped, a cover member that closes one end of the case, and a circuit
unit that enables the LEDs to emit light. The LEDs are mounted on the mounting
board, the mounting board is installed on a surface of the cover member, and the
circuit unit is fitted inside the case (Patent Literature 1).
[0004]
In the LED lamp disclosed in Patent Literature 1, the cover member has a
fimction of conducting heat generated when the LEDs emit light to the case, and the
case has a heat dissipation function of dissipating heat that is conducted from the
cover member. Thus, the cover member and the case are formed from metal material
having a high thermal conductivity, and the cover member and the case are joined in
contact with each other.
[0005]
In order to ensure that the circuit unit is in an insulated state inside the case,
1
a resin housing that howesLthec ircuit unit -is provided inside the case. Thus, the
circuit unit is isolated &om the case. The resin housing consists primarily of a main
part that is cylindrical and houses the circuit unit, and a cover part that closes an
opening at one end of the main part. The cover part is attached to the cover member
5 by using a screw.
[Citation List]
[Patent Literature]
[0006]
[Patent Literature 11
10 Japanese Patent Publication No. 46121 20
[Summary of Invention]
[Technical Problem]
[0007]
In recent years, consideration is being given to resinification of the case in
15 an LED lamp to achieve weight reduction. In such a case, the main part mentioned
above, for ensuring insulation, is unnecessary. However, insulation is still necessary
between the cover member, which is made of metal, and the circuit unit.
[0008]
When using the cover part of the housing in the LED lamp mentioned above
20 as insulation between the cover member and the circuit unit, the cover part and the
cover member need to be fixed by a screw, and assembly is awkward.
The present invention aims to provide a lamp having a simple configuration
that easily ensures insulation of the circuit unit.
25 [Solution to Problem]
[OO lo]
The lamp pertaining to the present invention includes: an envelope formed
by a globe and a case, a light emitting element disposed inside the envelope, and a
. ---circuit-d disposed insickthe envelope and codgured to light the light-emitting
element, wherein the light-emitting element is attached to an extension member that
extends from a mount into the globe, the mount closing an opening at one end of the
case, the circuit unit being disposed inside the case, which is closed by the mount,
5 the mount is made of an electrically conductive material, and an insulation member
is disposed inside the case to insulate the circuit unit from the mount, the mount has
a cylinder portion and a cover portion that closes one end of the cylinder portion,
and the extension member is mounted on the cover portion of the mount, and the
insulation member has a cylindrical portion that is inserted into the cylinder portion
10 of the mount and has a protrusion portion that is formed on an outer circumference
of the cylindrical portion and that protrudes toward the mount, the insulation
member being attached to the mount by the protrusion portion pressing on an inner
surface of the cylinder portion of the mount.
[Advantageous Effects of Invention]
15 [OOll]
According to the above configuration, by inserting the cylindrical portion of
the insulation member, which ensures insulation of the circuit unit, into the cylinder
portion of the mount, the protrusion portion of the insulation member presses the
inner surface of the cylinder portion of the mount. Thus, assembly is easy since the
20 insulation member is attached to the mount, as described above, and a simple
configuration using the protrusion portion is implemented.
[OO 1 21
Further, the protrusion portion is a plurality of protrusion portions disposed
in a circumferential direction of the cylindrical portion, each protrusion portion
25 being elongated in a direction parallel to the central axis of the cylindrical portion.
Alternatively, the protrusion portion is a plurality of protrusion portions disposed in
a circumferential direction of the cylindrical portion, each protrusion portion having
a bump shape.
a- , =..-, .---..a-,- -- . /.- *. ' *.-- - ,7 - - .-eL.-- ,- .-*,. . . -7 - - -.
r"
[00 131
Further, the insulation member has an end wall disposed at one of two ends
of the cylindrical portion, and the protrusion portion is disposed closer to the other
5 one of the two ends of the cylindrical portion than the one end at which the end wall
is disposed. Furthermore, the cover portion of the mount and the end wall of the
insulation member are in contact with each other, a through hole passes through the
cover portion of the mount and the end wall of the insulation member, and the
extension member is fixed by a screw member, which has a head portion disposed
10 inside the cylindrical portion of the insulation member and a screw portion that
passes through the through hole.
[Brief Description of Drawings]
[00 141
Fig. 1 is a perspective view of an LED lamp pertaining to an embodiment.
Fig. 2 is a front elevation cross-sectional view of the LED lamp.
Fig. 3 is an exploded perspective view of the LED lamp.
Figs. 4A and 4B illustrate the structure of an LED module, Fig. 4A being a
plan view of the LED module, and Fig. 4B being a cross-sectional view of the LED
module taken along the line A-A' in Fig. 4A.
20 Figs. 5A and 5B illustrate the structure of a case, Fig. 5A being a plan view
of the case, and Fig. 5B being a cross-sectional view of the case taken along the line
B-B' in Fig. 5A.
Fig. 6A is a perspective view of a state in which an insulation member is
attached to a mount, and Fig. 6B is a perspective view of the insulation member and
25 the mount in a separated state.
Fig. 7A is a plan view of a state in which the insulation member is attached
to the mount, and Fig. 7B is a plan view of the insulation member and the mount in a
separated state.
Fig. 8 is a cross-sectional view taken along the line C-C' in Fig. 7A.
Figs. 9A and 9B illustrate a state in which a circuit substrate is attached to
the case, Fig. 9A being a plan view and Fig. 9B being a cross-sectional view.
Figs. 10A and 10B are illustrations for explaining a state in which a base
5 assembly is attached to the case, Fig. 10A being a plan view and Fig. 10B being a
cross-sectional view.
Fig. 11 is a schematic view of a lighting device pertaining to another
embodiment.
[Description of Embodiment]
10 [0015]
The materials and values used in the embodiment only indicate preferable
examples, and the present invention is not limited in this way. Also, appropriate
changes and modifications may be made without departing from the spirit and scope
of the present invention. Further, a combination of the present embodiment and
15 modifications, or a combination of modifications, may be made as long as such
combination does not cause contradiction. Furthermore, the scale of the components
in each drawing differs fiom their actual scale.

1. Overall Configuration
20 Fig. 1 is a perspective view of an LED lamp 1 pertaining to the present
embodiment. Fig. 2 is a fiont elevation cross-sectional view of the LED lamp 1. Fig.
3 is an exploded perspective view of the LED lamp 1.
[OO 161
The LED lamp 1 (corresponding to the lamp pertaining to the present
25 invention) includes an LED module 5, a globe 7, a case 9, a base 11, a mount 13, an
extension member 15, a circuit unit 17, and an insulation member 19. The LED
module 5 includes LEDs 3 that are a light source (refer to Fig. 4B). The globe 7 has
the LED module 5 disposed therein. The case 9 is attached to an end portion of the
5
globe 7-at a ~ osidpe th ereof. The base 11 is attached to an end of the case 9 (the
lower end in Fig. 1). The mount 13 closes another end of the case 9 and is made of
metal. The extension member 15 is attached to the mount 13, extends into the globe
7, and, at the end of the extension, the LED module 5 is mounted thereon. The
I 5 circuit unit 17 is housed in the case 9, which is closed by the mount 13. The
insulation member 19 is disposed in the case 9 and ensures insulation between the
mount 13 and the circuit unit 17.
[OO 1 71
Note that in the present specification, a base direction is a direction along a
10 central axis of the LED lamp downwards toward the base 1 1 and a globe direction is
the opposite direction along the central axis of the LED lamp upwards toward the
globe 7. Also, an envelope housing the LED module 5 and the circuit unit 17
includes the globe 7 and the case 9.
2. Configuration of Parts
15 (1) LED Module
Figs. 4A and 4B illustrate the structure of the LED module 5. Fig. 4A is a
plan view of the LED module 5, and Fig. 4B is a cross-sectional view of the LED
J module 5 taken along the line A-A' in Fig. 4A.
[OO 1 81
20 As shown in Fig. 1, Fig. 2, Fig. 3, and particularly in Fig. 4A and Fig. 4B,
the LED module 5 includes a mounting board 21, the LEDs 3, and a sealant 23. The
LEDs 3 are mounted on a surface of the mounting board 21 (an upper surface, which
is a side facing away from the base 1 1). The sealant 23 covers the LEDs 3.
[OO 191 -
25 The mounting board 21 has a rectangle shape in plan view, and is formed,
for example, from a Iight-transmissive material such as glass or alumina, in order to
avoid obstructing light that is emitted backwards, in the base direction, from the
LEDs 3.
6
, - .- --., ---;[(-jO'q - - - - - - -. - . -- = -- *
As shown in Fig. 4A, the mounting board 21 has a conduction path 25,
which is composed of a connection pattern 25% a terminal pattern 25b, and a
terminal pattern 25c. The connection pattern 25a is for connecting the LEDs 3 (in
5 serial connection and/or parallel connection). The terminal pattern 25b and the
terminal pattern 25c are for connecting a corresponding one of a lead wire 27 and a
lead wire 29, which are connected to the circuit unit 17. Note that the conduction
path 25 is also made of light-transmissive material, such as ITO, to allow
transmission of light fiom the LEDs 3.
10 [0021]
As shown in Fig. 3 and Fig. 4B, the mounting board 21 has two
through-holes 3 1 passing therethrough, formed such that one through-hole 3 1 passes
through the terminal pattern 25b and the other through-hole 3 1 passes through the
terminal pattern 25c. The lead wire 27 passes through the one through-hole 31 and
15 the lead wire 29 passes through the other through-hole 3 1. A tip portion of the lead
wire 27 and a tip portion of the lead wire 29 are adhered (connected) to the terminal
pattern 25b and the terminal pattern 25c, respectively, by soldering 33.
COO221
The mounting board 21 has, in a center thereof in plan view, a fitting hole
20 3 5. The fitting hole 3 5 fits to a fitting protrusion portion 87 of the extension member
15. The fitting hole 35 has a polygonal shape in plan view, and specifically a
rectangular shape. Note that the fitting protrusion portion 87 of the extension
member 15 also has a rectangular shape, to prevent attachment of the mounting
board 2 1 to the extension member 15 in an incorrect orientation.
25 [0023]
The LEDs 3 are mounted on the mounting board 21 in the form of chips. As
shown in Fig. 4A and Fig. 4B, the LEDs 3 are disposed at intervals (for example,
regular intervals) in two parallel rows in a longitudinal direction of the mounting
7
+ v - - - board21.
[0024]
The sealant 23 is primarily composed of a light-transmissive material such
as silicone resin, for example. The sealant 23 has a sealant function of preventing air
5 and water penetrating to the LEDs 3, and a wavelength conversion function of
converting the wavelength of light from the LEDs 3. The sealant function is
implemented by coating each of the rows in which the LEDs 3 are arranged. The
wavelength conversion bction is implemented by7 for example, mixing a
conversion material into the light-transmissive material that converts a certain
10 wavelength of light, such as fluorescent particles.
(2) Globe
As shown in Fig. 1, Fig. 2 and Fig. 3, the globe 7 has a similar shape to a
bulb of an incandescent light bulb (also called a glass bulb), and is a so-called
A-type bulb. The globe 7 is made fiom light-transmissive material, such as glass.
15 [0025]
The globe 7 includes a spherical portion 7a that has a hollow spherical
shape and a cylindrical portion 7b that has a cylindrical shape. The cylindrical
portion 7b decreases in diameter as distance fiom the spherical portion 7a increases.
[0026]
20 As shown in Fig. 2, an opening end portion 7c exists at an end portion of the
cylindrical portion 7b, opposite the spherical portion 7a. The opening end portion 7c
is fixed to the case 9 by adhesive 37. As shown in the enlargement in Fig. 2, an end
edge 7d of the opening end portion 7c has a bulging spherical shape (a sphere
having a diameter greater than the thickness of the remainder of the opening end
25 portion 7c). The bulging spherical shape prevents the globe 7 from separating from
the case 9 (separating fiom the adhesive 37), because even if adhesion is lost
between the globe 7 and the adhesive 37, the end edge 7d of the globe 7 is engaged
with the adhesive 37.
(3) Chse
The case 9 is composed of resin material such as polybutylene terephthalate
(PBT) and has a shape similar to the portion of a bulb of an incandescent light bulb
that is near a base. In the present embodiment, along a central axis of the case 9, the
5 case 9 has a large diameter portion 9a in the globe direction and a small diameter
portion 9b in the base direction. The large diameter portion 9a has a trumpet shape
that gradually increases in diameter with distance fiom the small diameter portion
9b.
[0027]
10 The case 9 has a hction of dissipating heat generated by the circuit unit 17,
which generates heat when the LED lamp 1 is lit, to the outside of the case 9. As
described above, the circuit unit 17 is housed inside the case 9. Heat dissipation is
performed by heat conduction and radiation fiom the case 9 to the outside air, and
by convection of the outside air.
15 [0028]
As shown in the enlargement in Fig. 2, an opening at one end of the case 9
is closed by the insertion of the mount 13 into an end portion of the large diameter
portion 9a. Also, the opening end portion 7c of the globe 7 is inserted into a gap
between an outer circumferential surface of the mount 13 and an inner
20 circumferential surface of the large diameter portion 9a of the case 9. In such a state,
the case 9, the globe 7, and the mount 13 are fixed by the adhesive 37.
[0029]
Figs. 5A and 5B illustrate the structure of the case 9. Fig. 5A is a plan view
of the case 9, and Fig. 5B is a cross-sectional view of the case 9 taken along the line
25 B-B' in Fig. 5A.
[0030]
As shown in Fig. 3 and Figs. 5A and 5B, disposed inside the large diameter
portion 9a is a reinforcement unit 41, a fixing unit 43, a support unit 45, a support
9
unit 46, and a rotation restriction unit 47. The reinforcement unit 41 reinforces the
large diameter portion 9a. The fixing unit 43 fixes the insulation member 19 that is
attached to the mount 13. The support unit 45 and the support unit 46 support the
circuit unit 17. The rotation restriction unit 47 restricts rotation of the mount 13.
5 [0031]
As shown in Fig. 3, the reinforcement unit 41 has an arc portion 41% and a
connection portion 41b. The arc portion 41a has an arc shape that follows a
circumferential wall of the large diameter portion 9a (which has a cylindrical shape).
The arc portion 41a is elongated in a direction that is parallel to the central axis of
10 the large diameter portion 9a. The connection portion 41 b connects each end of the
arc portion 41 a in a circumferential direction thereof to the large diameter portion 9a.
Due to the reinforcement by the reinforcement unit 41, the thickness of the
circumferential wall of the large diameter portion 9a is reduced and the weight of the
case 9 is reduced. Note that the arc portion 41% in plan view (Fig. 5A), has a shape
15 of an interrupted circle centered on a central axis of the large diameter portion 9a.
[0032]
As shown in Fig. 5A, the reinforcement unit 41 is provided in a plurality, in
the present embodiment four reinforcement units 41, at regular intervals in a
circumferential direction of case 9. Four intervals exist between the four
20 reinforcements units 41 in the circumferential direction of the case 9, and by passing
through two of the four intervals, the lead wires 27 and 29 connect to the circuit unit
17 and the LED module 5.
[003 31
The fixing unit 43 has a support portion 43a and a locking portion 43b. The
25 support portion 43a supports the insulation member 19 fiom the base direction. The
locking portion 43b locks the insulation member 19 into position fiom the globe
direction (refer to Fig. 1 OB).
[0034]
- - - - Thie support portion 43a protrudes in the g l o b e k ~ o-n(u pwards) fiom a
substantially central position of an upper surface of the arc portion 41a in the
circumferential direction of the case 9. Note that it suffices that the support portion
43a supports the insulation member 19 from the base direction, and therefore the
5 support portion 43a need not be a protrusion.
[0035]
The fixing unit 43 is provided in a plurality, in the present embodiment four
fixing units 43, at regular intervals in a circumferential direction of the case 9. In
plan view, each of the locking portions 43b is positioned between two of the
10 reinforcement units 41 that are adjacent in the circumferential direction of the case 9.
Note that the present invention is not limited to four of the locking portions 43b
being provided, and two or more of the locking portions 43b are sufficient to fix the
insulation member 19 into position.
[0036]
As shown in Fig. 5B, each of the support unit 45 and the support unit 46 is a
ridge portion protruding from an inner surface of a different one of the arc portions
41a toward the central axis of the large diameter portion 9% and is elongated toward
the small diameter portion 9b. In the present embodiment three support units 45 and
one support unit 46 are provided, for a total of four ridge portions being provided.
20 [0037]
Each of the support unit 45 is composed of a fitting portion 45a and a
support portion 45b. An upper end of the fitting portion 45a extends to an upper end
of the reinforcement unit 4 1 (the arc portion 41 a) and fits into a corresponding one
of a cutaway portion 91 a, a cutaway portion 91 b, and a cutaway portion 91 c that are
25 formed on a circuit substrate 91 of the circuit unit 17. The support portion 45b is
positioned closer to the central axis of the case 9 than the fitting portion 45a and
supports the circuit substrate 91 fiom the base direction. Thus, the support units 45
support the circuit substrate 91 and restrict rotation of the circuit substrate 91 inside
11
-r m e 9. - - + .aa.*- -- - -:; +.:>-. . 7 ---- + -- .- - zr t
[0038]
The upper end of the support portion 45b is positioned closer to the base 11
than the upper end of the fitting portion 45a, such that a portion of the upper end of
5 each of the support units 45 that is closer to the center of the case 9 is lower than the
other portion of the upper end of each of the support units 45, which is farther from
the center of the case 9. Thus the supports units 45 each have a stepped shape.
[0039]
The support unit 46 is composed of a support portion 46a that supports the
10 circuit substrate 91 from the base direction. An upper end position of the support
portion 46a is the same as the upper end position of the support portion 45b of the
support unit 45. Thus, the circuit substrate 91 is supported orthogonally to the
central axis of the case 9, by the support portions 45b of the support unit 45 and the
support portion 46a of the support unit 46.
15 [0040]
The rotation restriction unit 47 is formed as a ridge protruding from an area
of the inner surface of the large diameter portion 9a where the mount 13 is to be
attached, toward the central axis of the large diameter portion 9a. Further, the
rotation restriction unit 47 is elongated along the central axis of the case 9, in the
20 base direction. Furthermore, the rotation restriction unit 47 fits into a restriction
groove 13f of a flange portion 13c of the mount 13. Thus, the rotation restriction
unit 47 restricts the mount 13 from rotating inside the case 9.
[004 11
The small diameter portion 9b has a joining unit that joins to the base 11.
25 Specifically, an outer circumferential surface of the small diameter portion 9b has a
male thread 49 that mates with a thread of the base 1 1, which is an Edison-type base.
[0042]
As shown in Fig. 3 and Fig. 5B, part of the outer circumferential surface of
12
the small diameter portion 9b has a fixing groove 51 and a cutaway portion 53. The
fixing groove 5 1 is for fixing a lead wire 67 that connects the base 11 and the circuit
unit 17. The cutaway portion 53 is at a lower end of the small diameter portion 9b, is
connected to the fixing groove 51, determines the position of the lead wire 67, and
fixes the lead wire 67 into position. The fixing groove 51 is elongated in a direction
parallel to the central axis of the case 9.
(4) Base
The base 11 is for receiving power from a socket of a lighting apparatus
when the LED lamp 1 is attached to the lighting apparatus and lit.
[0043]
The base 11 is not specifically limited to any type of base, but an
Edison-type base is used in the present embodiment, as shown in Figs. 1-3. As
shown in Fig. 2, the base 11 is composed of a shell portion 61 and an eyelet portion
65. The shell portion 61 has a cylindrical shape and a circumferential wall that is
threaded. The eyelet portion 65 is attached to the shell portion 61, and insulation
material 63 is between the eyelet portion 65 and the shell portion 61.
[0044]
The lead wire 67 is connected to the shell portion 61 by being bent back
toward the outer circumferential surface of the case 9 at the cutaway portion 53 at
the lower end of the small diameter portion 9b, by being covered by the shell portion
61 while being inserted into the furing groove 51 of the case 9. Further, a lead wire
69 is connected to the eyelet portion 65 by soldering. Thus, the base 11 is connected
to the circuit unit 17.
(5) Mount
The mount 13 closes an opening at an upper end of the case 9 and has the
extension member 15 attached thereto. The mount 13 is formed fkom metal material
(for example, aluminium material) for easy conduction of heat generated by the LED
module 5 upon light emission, to the globe 7, the case 9, etc.
13
- . - _ , I - .[g@$q-- ,- - =x - . 2 1 - - - t - . --- . -- .
Fig. 6A is a perspective view of a state in which the insulation member 19 is
attached to the mount 13, and Fig. 6B is a perspective view of the insulation member
19 and the mount 13 in a separated state. Fig. 7A is a plan view of the state in which
5 the insulation member 19 is attached to the mount 13, and Fig. 7B is a plan view of
the insulation member 19 and the mount 13 in the separated state. Fig. 8 is a
cross-sectional view taken along the line C-C' in Fig. 7A.
[0046]
As shown in the upper portion of Fig. 6B, the mount 13 has a cylinder
10 portion 13% a cover portion 13b, and the flange portion 13c. The cover portion 13b
closes an opening at an upper end of the cylinder portion 13a in a central axis
direction of the cylinder portion 13a. The flange portion 13c protrudes fiom a lower
end of the cylinder portion 13a in a central axis direction, outward in a radial
direction fiom the central axis of the cylinder portion 13a. A central area of an upper
15 surface of the cover portion 13b is an attachment area 71 for attaching the extension
member 1 5.
[0047]
As shown in Fig. 3 and the upper portion of Fig. 6B, the flange portion 13c
is provided in a plurality (for example, four flange portions 13c) at regular intervals
20 in a circumferential direction of the cylinder portion 13a. Further, as shown in Fig. 8,
at portions of the lower end of the cylinder portion 13a without the flange portion
13c (indicated as 13d in Fig. 6B), step portions 13e that are indented toward the
central axis of the mount 13 are formed.
[0048]
25 As shown in the enlargement in Fig. 2, the adhesive 37 wraps around the
step portion 13e of the mount 13. Thus, the provision of the step portions 13e
prevents the adhesive 37 fiom separating fiom the case 9 and the mount 13 even if
the adhesive 37 between the case 9 and the mount 13 loses adhesion thereto, since
14
I
- - .I - _-- . .-._ -- % - the portion of the adhesive 37 around the step portions 13e is engaged with the step
portions 13e. Note that step portions may instead be formed on the case 9 for the
adhesive 37 to wrap around.
[0049]
5 One of the four flange portions 13c has formed therein the restriction
groove 13f, which is elongated parallel to the central axis of the mount 13. When the
mount 13 is attached to the case 9, the restriction groove 13f fits onto the rotation
restriction unit 47.
[0050]
10 The attachment area 71 has a fitting unit that fits with the extension member
15 (refer to Fig. 3). As shown in the upper portion of Fig. 6B, the fitting unit is
formed by a fitting protrusion portion 73 that protrudes upwards, for fitting to a
fitting groove 81 at a lower end portion of the extension member 15. Two
through-holes 75 and a through-hole 77 are formed in the fitting protrusion portion
15 73, penetrating the fitting protrusion portion 73 in the direction of thickness of the
cover portion 13b. The two through-holes 75 are for the lead wires 27 and 29, which
connect the circuit unit 17 and the LED module 5. The through-hole 77 is for a
screw 121 that is for fixing the extension member 15.
[005 11
20 The through-hole 77 is positioned along the central axis of the mount 13 (in
plan view, the center of the cover portion 13b). As shown in the upper portion of Fig.
7B, the through-holes 75 are positioned on an imaginary straight line D that passes
through the through-hole 77. In plan view, the imaginary straight line D passes
through a substantially central point between opposing pairs of the flange portion
25 13c in the circumferential direction of the mount 13.
(6) Extension Member
As shown in Fig. 3, the extension member 15 has an overall shape of a rod
and is formed from metal material, which has high thermal conductivity. The
15
exte~~lomne mber 15 is composed of a base attachment partion -15a that is attached -- - -
to the mount 13, a module attachment portion 15b to which the LED module 5 is
attached, and a connection portion 15c that connects the base attachment portion 15a
and the module attachment portion 15b.
5 [0052]
The base attachment portion 15a has a circular truncated cone shape that
tapers off toward the connection portion 15c. The base attachment portion 15a has a
fitting groove 81 that is rectangular in plan view and is for fitting to the fitting
protrusion portion 73 of the attachment area 71 of the mount 13. In addition, as
10 shown in Fig. 2, the base attachment portion 15a has two through-holes 83 for the
lead wires 27 and 29, and a screw-hole 85 for furing the mount 13 into position. The
two through-holes 83 are aligned with the two through-holes 75 of the mount 13 and
the screw-hole 85 is aligned with the through-hole 77 of the mount 13.
[0053]
As shown in Fig. 3, the module attachment portion 15b has a shape similar
to an inversion of the shape of the base attachment portion 15a. The module
attachment portion 15b has a modified circular truncated cone shape that lacks
portions of the circular truncated cone shape that would protrude beyond the
rectangular shape of the LED module 5 in plan view. As shown in Fig. 2, the fitting
20 protrusion portion 87 is formed at a central position of an upper end surface of the
module attachment portion 15b, and is for fitting to the fitting hole 35 that is formed
in the mounting board 21 of the LED module 5.
(7) Circuit Unit
The circuit unit 17 receives power via the base 11, converts the power to
25 LED applicable power, and supplies the converted power to the LED module 5 (the
LEDs 3). As shown in Fig. 3, the circuit unit 17 is composed of the circuit substrate
91 and electrical components 93,95, and 97 that are mounted on the circuit substrate
91.
{0054] - - - - +. ___ - . -__. .I . - L . .. ._,- .r -
In plan view, the circuit substrate 91 has a shape similar to a circular shape,
and has the cutaway portion 91a and the cutaway portion 91b that correspond to
protruding portions of the inner circumference of the large diameter portion 9a of the
case 9 (specifically, an upper portion of the fitting portion 45a). Thus, the circuit
substrate 91 is restricted fiom rotating inside the case 9. Two cutaway portions 91d
are formed on a circumferential rim of the circuit substrate 91, opposite each other
across the center of the circuit substrate 91. The two cutaway portions 91d are for
the lead wires 27 and 29, which connect the circuit unit 17 and the LED module 5.
When the LED lamp 1 is in an assembled state, the two cutaway portions 91d are
positioned, in plan view, along the imaginary straight line D and an imaginary
straight line E, which are shown in Fig. 7B.
[0055]
The electrical components of the circuit unit 17 include a rectification
circuit that rectifies commercial power (AC) received via the base 11, a smoothing
circuit that smoothes rectified DC power, a step-down circuit that steps-down a
smoothed voltage to a predetermined voltage, etc.
[0056]
Here, the rectifjring circuit includes a diode bridge 93, the smoothing circuit
includes a capacitor 95, and the step-down circuit includes a transistor 97, a
capacitor 99, a switching element, etc.
[0057]
Note that, of the electrical components, the diode bridge 93, for example, is
attached to a main surface of the circuit substrate 91 on side that is closer to the
globe 7 than an opposite side of the circuit substrate 91 that is closer to the base 11.
Also, the circuit substrate 91 is between the support unit 45 and the insulation
member 19, inside the case 9 in such a way that there is a slight possibility of the
circuit substrate 91 moving up and down.
17
(8) Insulation Member % - -
As shown in Fig. 3, Fig. 6A, Fig. 6B, Fig. 7A, Fig. 7B, and Fig. 8, the
insulation member 19 has a bottomed cylindrical shape, is formed fiom a resin
material, and is inserted into and fixed to the inside of the cylinder portion 13a of the
mount 13. The insulation member 19 has a bottomed cylinder portion 19a and a
flange portion 19b. The bottomed cylinder portion 19a has a cylindrical portion that
is a circumferential wall of the insulation member 19 and an end wall at one end of
the cylindrical portion. The flange portion 19b projects outward in a radial direction
fiom the other end of the cylindrical portion of the bottomed cylinder portion 19a.
As shown in the lower portion of Fig. 7B, a plurality of protrusion portions 101
(here, four protrusion portions 101) are formed at regular intervals in a
circumferential direction on an outer circumferential surface of the bottomed
cylinder portion 19a. The protrusion portions 101 are for fixing the insulation
member 19 to the mount 1 3.
[0058]
A pair of a protrusion 103a and a protrusion 103b are formed on the flange
portion 1 9b, protruding upward into an area between pieces of the flange portion 1 3c
that are adjacent in the circumferential direction of the cylinder portion 13a (an area
13d where the flange portion 13c is not present). Four pairs of the protrusion 103a
and the protrusion 103b are formed. Each pair corresponds to one of the four areas
where the flange portion 13c of the mount 13 is not present. Thus, the pairs of the
protrusion 103a and the protrusion 103b are usable as a guide for aligning the
insulation member 19 and the mount 13 when attaching the insulation member 19 to
the mount 13, and restrict rotation of the insulation member 19 relative to the mount
13 when the insulation member 19 is attached to the mount 13.
[0059]
As shown in Fig. 3, Fig. 6A, and Fig. 6B, a surface of the end wall of the
bottomed cylinder portion 19a that faces the globe direction is flat. As shown in Fig.
18
8, a thick portion 104 protrudes in the base direction fiom a central area of a-surface
of the end wall of the bottomed cylinder portion 19a that faces the base direction.
Two through-holes 105 are provided that penetrate the thick portion 104, for the lead
wires 27 and 29 that connect the circuit unit 17 and the LED module 5. A
5 through-hole 107 is provided that penetrates the thick portion 104, for the screw 121
that is for fixing the extension member 15 into position.
[0060]
As shown in the bottom portion of Fig. 7B, the through-hole 107 is
positioned along a central axis of the insulation member 19 (in plan view, at the
10 center of the end wall), and the two through-holes 105 are positioned on the
imaginary straight line E that passes across the through-hole 107. In plan view, the
imaginary straight line E is coincident with the imaginary straight line D. Note that
the through-holes 105 are wider than the through-holes 75 of the mount 13, in order
that the lead wires 27 and 29 pass through the two through-holes 105 easily.
15 [0061]
As shown in Fig. 8, in a substantially central area of the thick portion 104, a
concave portion 1 04a is formed for fitting a head portion 12 1 a of the screw 1 2 1 that
connects the mount 13, the insulation member 19, and the extension member 15.
[0062]
20 Convex protrusion portions 19c protrude downward fiom a lower surface of
the flange portion 19b, and are formed in two locations opposing each other. The
convex protrusion portion 19c is for restricting upward movement of the circuit
substrate 91 of the circuit unit 17. Note that the convex protrusion portion 19c and
the circuit substrate 91 of the circuit unit 17 are in contact, and therefore a gap exists
25 between the circuit substrate 91 and the insulation member 19 corresponding to a
protrusion amount of the convex protrusion portion 19c. The lead wires 27 and 29
pass through the gap, and therefore disconnection of the lead wires 27 and 29 is
prevented.
- - 3: Assemt>ly - . . -- ,: 2 -a -- - f _ , , . _- - . - - I .-- - . .
The following is an explanation of assembly of the LED lamp 1, and
particularly of how the parts join together. Note that in the following, only the
joining of representative parts is explained, and the explanation may not coincide
5 with the actual order of assembly of the LED lamp 1.
(1) Module and Extension Member
Joining of the LED module 5 and the extension member 15 is performed by
(i) fitting the fitting hole 35 that is formed in the mounting board 21 of the LED
module 5 to the fitting protrusion portion 87 that is formed at the upper end surface
10 of the module attachment portion 15b of the extension member 15, (ii) inserting the
lead wire 27 through one of the through-holes 31 and inserting the lead wire 29
through the other one of the through-holes 3 1, and (iii) fixing the upper ends of the
lead wires 27 and 29 to the mounting board 21 by the soldering 33.
[0063]
15 Here, since the fitting hole 35 and the fitting protrusion portion 87 each
have a polygonal shape in plan view, rotation of the LED module 5 relative to the
extension member 15 is restricted. Also, the center of the mounting board 21 is fixed
in position by the fitting protrusion portion 87, and both end portions of the
mounting board 21 in a longitudinal direction of the mounting board 21 are fixed in
20 position by the lead wires 27 and 29. Thus, the LED module 5 is supported by the
extension member 1 5, etc., in a stable state.
[0064]
Note that, for increasing the coherence (contact) or reducing imperfections
in the contact area between the mounting board 21 and the module attachment
25 portion 15b, the mounting board 21 and the module attachment portion 15b may be,
for example, fxed by an adhesive having a high thermal conductivity. Note that by
increasing coherence between the mounting board 21 and the module attachment
portion 15b, the amount of heat conducted from the LED module 5 to the extension
20
..- - - - member 15 is Increased.
(2) Insulation Member and Mount
The insulation member 19 is attached to the mount 13 by inserting the
bottomed cylinder portion 19a inside the cylinder portion 13a of the mount 13. The
5 protrusion portions 101, which come in contact with an inner surface of the cylinder
portion 13% are formed on an outer circumferential surface of the bottomed cylinder
portion 19a of the insulation member 19. Thus, the insulation member 19 is
press-fitted to the mount 13.
[0065]
10 Since the mount 13 is formed from metal material and the insulation
member 19 is formed from resin material, it suffices to adjust the protrusion amount
of the protrusion portions 10 1 to ensure that the protrusion portions 10 1 contact with
the mount 13.
[0066]
In other words, if the protrusion amount of the protrusion portion 101 is
slightly larger than the gap between the inner circumferential surface of the cylinder
portion 13a of the mount 13 and the outer circumferential surface of the bottomed
cylinder portion 19a of the insulation member 19, compression of the protrusion
portion 101 due to press-fitting reduces incidences of separation of the insulation
20 member 19 from the mount 13.
[0067]
On the other hand, if the protrusion amount of the protrusion portion 101 is
considerably larger than the gap between the inner circumferential surface of the
cylinder portion 13a of the mount 13 and the outer circumferential surface of the
25 bottomed cylinder portion 19a of the insulation member 19, depression
(deformation) of the cylindrical portion (circumferential wall) of the bottomed
cylinder portion 19a in the vicinity of the protrusion portions 101 due to press-fitting
reduces incidences of separation of the insulation member 19 from the mount 13.
21
. - f00681
As such, it suffices that the variation in the protrusion amount of the
protrusion portions 101 is adjusted such that contact with the mount 13 is ensured at
the lower limit of the protrusion amount of the protrusion portions 101. Thus, the
5 protrusion portions 101, the insulation member 19, and the mount 13 do not require
high manufacturing precision, and the insulation member 19 can easily be attached
to the mount 13. In addition, easy separation of the insulation member 19 fkom the
mount 13 is prevented.
[0069]
10 Note that the mount 13 having the insulation member 19 attached thereto is
called a base assembly.
(3) Extension Member and Base Assembly
The extension member 15 and the base assembly are joined (connected) by
the screw 121
15 [0070]
First, the fitting groove 81 on a lower surface of the base attachment portion
15a of the extension member 15 and the fitting protrusion portion 73 are fitted
together to form a fitted state. In the fitted state, the through-hole 77 of the mount 13
and the screw-hole 85 of the extension member 15 are aligned, and the screw 121 is
20 screwed into the screw-hole 85 of the extension member 15 from the insulation
member 19 side of the base assembly via the through-hole 107 and the through-hole
77. In this way, assembly of the extension member 15 and the base assembly is
completed.
[0071]
25 Note that, in plan view, the fitting groove 81 of the extension member 15
and the fitting protrusion portion 73 of the mount 13 have a shape that is not a
circular shape, centered on the axis of the screw 12 1. Here, the fitting groove 8 1 and
the fitting protrusion portion 73 have matching elliptical shapes that are elongated in
22
a direction parallel to a line through the axis of the screw 121. Thus, even when the
screw 121 is screwed into the screw-hole 85 of the extension member 15, rotation of
the extension member 15 relative to the base assembly is prevented.
[0072]
Note that here, the screw 121 is made of metal. In order to ensure insulation
between the screw 12 1 and the circuit substrate 91, after the screw 121 is screwed in
and fured inside the concave portion 104a of the thick portion 104 of the insulation
member 19, the inside of concave portion 104a is filled up with a silicon resin 123,
covering the screw 121 (refer to Fig. 2). The silicon resin 123 is insulative. Note that
the silicon resin 123 also has a function of preventing loosening of the screw 121
and preventing separation of the screw 121 from the screwed-in position.
(4) Case and Circuit Unit
The circumferential rim of the circuit substrate 91 of the circuit unit 17 does
not have a perfectly circular shape, and the circuit substrate 91 has the cutaway
portions 91 a, 91 b, and 91 c. The cutaway portions 9 la, 9 1 b, and 91 c correspond to
the upper portions of the three fitting portions 45a in the inner circumferential
surface of the case 9. The cutaway portions 91 a, 91 b and 91 c are each aligned to the
corresponding one of the three fitting portions 45a and the circuit substrate 91 is
inserted into the case 9 such that the capacitor 99 faces in the base direction.
[0073]
Figs. 9A and 9B illustrate a state in which the circuit substrate 91 is inserted
into the case 9. Fig. 9A is a plan view and Fig. 9B is a cross-sectional view.
[0074]
In plan view, the fitting portion 45a protrudes toward the center of the case
9. Thus, as shown in Fig. 9A, when the three fitting portions 45a are fitted to the
cutaway portions 91% 91 b, and 91c, respectively, the circuit substrate 91 does not
rotate relative to the case 9.
[0075]
As shown in -Fig. 9A, thecircderential rim of the circuit substrate 91 that
is not cutaway portions, etc. is in contact with or near to the arc portion 41a of the
reinforcement unit 41. Thus, the circuit unit 17 does not move in a direction
orthogonal to the central axis of the case 9.
[0076]
Also, a portion of the support unit 45 relatively close to the center of the
case 9 is stepped down in the base direction. As shown in Fig. 9B, the support
portion 45b, which is stepped down, and the support unit 46 support a rear surface of
the circuit substrate 91 (the rear surface facing the base direction).
[0077]
Note that, as shown in Fig. 9A, a gap exists between the cutaway portions
91d of the circuit substrate 91 and the locking portions 43b of the case 9. The lead
wire 27 passes through one of the gaps and the lead wire 29 passes through the other
one of the gaps.
(5) Case and Base Assembly
Figs. 10A and 10B are illustrations for explaining a state in which the base
assembly is attached to the case 9. Fig. 10A is a plan view and Fig. 10B is a
cross-sectional view.
[0078]
Note that in Fig. 1 OB, in order to show the joining of the flange portion 19b
and the fixing unit 43 of the case 9, a cross-section of the flange portion 19b is
shown as the cross-section of the insulation member 19.
[0079]
First, the locking portions 43b of the fixing units 43 of the case 9 and one
pair of the protrusions 103a and the protrusions 103b are aligned, and a lower
surface of the flange portion 19b is placed on an upper surface of the locking
portions 43b (a "placed state"). The aligning is performed such that the restriction
groove 13f of the base assembly (the mount 13) and the rotation restriction unit 47
24
&-together. By performing-the alignment, each of the locking portions 43b exists -
between a different one of the pairs of the protrusions 103a and the protrusions
103b.
[0080]
Then, while in the placed state, the base assembly is pushed towards the
small diameter in the base direction. As shown in Fig. 10B, as the locking portions
43b approach the small diameter portion 9b, the locking portions 43b protrude
farther toward the center of the case 9, such that an upper surface of each of the
locking portions 43b forms a slope. Therefore, by pushing the base assembly, the
flange portion 19b of the base assembly passes by the locking portions 43b. Thus, as
shown in Fig. 10B, a lower surface of the locking portions 43b comes in contact
with an upper surface of the flange portion 19b of the insulation member 19, and
movement of the base assembly in the globe direction is prevented.
[008 11
On the other hand, as shown in Fig. 10B, after the base assembly passes by
the locking portion 43b, a lower surface of the flange portion 19b of the insulation
member 19 comes in contact with the support portions 43a of the case 9 to be
supported from the base direction. Thus, the base assembly is attached to the case 9.
Since each of the locking portions 43b is positioned between one of each of the pairs
of the protrusions 103a and the protrusions 103b, rotation of the base assembly
inside the case 9 is prevented.
[0082]
Note that as shown in Fig. 1 OB, the circuit substrate 91 of the circuit unit 17
is positioned between the joining portion 45a of the case 9 and the insulation
member 19 such that, although some up and down movement is possible, the circuit
substrate 91 is contained inside the case 9.
4. Example of Implementation
The following is an explanation of an example of an implementation
... - pertaining to-the embodiment. . _ _ .*- _ _ - x ., - _ = . , - - - .- - -
[0083]
The LED lamp 1 is a replacement for a 20 W type incandescent light bulb,
power input to the LED module 5 is 3.5 W, and when the power input is 3.5 W, a
5 total luminous flux of the LED lamp 1 is 21 0 lm.
[0084]
The LEDs 3 emit blue light. As the conversion material, fluorescent
particles that convert blue light to yellow light are used. Thus, mixing of the blue
light emitted by the LEDs 3 and yellow light fiom wavelength conversion by the
10 fluorescent particles results in white light being emitted from the LED module 5 (the
LED lamp 1).
[0085]
In this example 24 LEDs 3 are disposed in two lines along a longitudinal
direction of the mounting board 21, each line including 12 of the LEDs 3 disposed at
15 regular intervals of 1.25 mm. The 12 LEDs 3 in each of the lines are electrically
connected in series, and the two lines of the LEDs 3 are electrically connected in
parallel.
[0086]
The mounting board 21 has a shape of a rectangle having short sides (L 1 in
20 Fig. 4A) that are 6 mm long, and long sides (L2 in Fig. 4A) that are 25 mm long.
The thickness of the mounting board 21 is 1 rnm. Light-transmissive alumina is used
as the material of the mounting board 21. Note that the volume of the mounting
board is 150 mm3.
[0087]
25 The mount 13 has an outer diameter (the outer diameter of the cylinder
portion 13a) of 30 mm and a height of 8 mm. The thickness of the cylinder portion
13a is 1.95 mm and the thickness of the cover portion 13b is 2.2 rnm. Note that an
amount of protrusion of the flange portion 13c fiom the outer circumference of the
26
- - cylmder portion 13a is 1.65 mm and the height of the flange portion 13c is 2.0 mm. ---
[0088]
The total length of the extension member 15 (the distance between an upper
surface and a lower surface of the extension member 15, excluding the fitting
5 protrusion portion 87 and the fitting groove 81) is 27 mm and the outer diameter of
the connection portion 15c is 5 mm. The outer diameter-of the lower end of the base
attachment portion 15a is 10 mm. In plan view the module attachment portion 15b
has a shape obtained by cutting away two portions from of a circle of diameter 8 mm.
The two portions are defined by a pair of lines parallel to an imaginary line through
10 the center of the circle and 3 mm distant from the imaginary line. The fitting
protrusion portion 87 has a rectangular shape having a length (a measurement in the
longitudinal direction of the LED module 5) of 1.9 mm and a width of 0.9 mm. Note
that the protrusion amount of the fitting protrusion portion 87 fiom the module
attachment portion 15b is 1 mm. Also note that the protrusion amount of the
15 protrusion portion 101 of the insulation member 19 is 0.3 mm and a length of the
protrusion portion 10 1 is 2 mm.
[0089]
A contact area between the LED module 5 and the extension member 15 is
46.53 mm2, and a contact area between the mount 13 and the extension member 15
20 (including the contact area between the fitting protrusion portion 73 and the fitting
groove 8 1) is 8 1.43 mm2.
5. Light Distribution Characteristics
In the LED lamp 1 pertaining to the embodiment, the LED module 5 is
disposed at a position inside the globe 7 corresponding to the position (for example,
25 in substantially the same position) of a light source of an incandescent light bulb (the
filament). Thus, even if the LED lamp 1 is attached to a lighting apparatus that has a
reflector for a conventional incandescent light bulb, the LED module 5 would be
positioned at a focal point of the reflector. Therefore, light distribution
27
- - characteristics-similar--ttoh e lightp-distribution -characteristics of the eonventiod
incandescent light bulb can be obtained.
[0090]
Also, since the mounting board 21 in the LED module 5 is
5 light-transmissive, light emitted backwards in the base direction fiom the LEDs 3 is
transmitted through the mounting board 21 and emitted fiom the globe 7 to the
outside of the LED lamp 1.
[009 11
Further, since the extension member 15 that supports the LED module 5 has
10 a long, thin, rod shape, obstruction of light emitted backward fiom the LEDs 3 is
decreased.
6. Heat Dissipation Paths
The LED lamp 1 pertaining to the embodiment dissipates heat that is
generated upon light emission by multiple paths. In the present embodiment, heat
15 that is generated when emitting light includes heat generated by the LEDs 3 and heat
generated by the circuit unit 17.
(1) Heat Generated by LEDs
(a) The heat generated by the LEDs 3 is conducted through the mounting board 21
of the LED module 5, the extension member 15, and then the mount 13. Heat
20 conducted to the mount 13 is conducted to the globe 7 and the case 9. A portion of
the heat conducted to the globe 7 and the case 9 is dissipated by the effects of heat
transfer, convection, and radiation. Also, a portion of the heat conducted to the case
9 is conducted from the base 1 1 to a socket on a lighting apparatus side.
(b) In the LED lamp 1, the globe 7 has a size and shape similar to a glass bulb of an
25 incandescent light bulb. Therefore, the envelope volume of the globe 7 is large, and
a large amount of heat is radiated from the globe 7. Thus, a large amount of heat
generated by the LEDs 3 is, via the extension member 15 and the mount 13,
dissipated fiom the globe 7.
.,- -.-.- -( 2)-HeatG enerated by Circuit Unit - W-- -- - - - - - - , - - -..- .. -..
Heat generated by the circuit unit 17 is conducted to the case 9 by heat
transfer, convection, and radiation. A portion of heat conducted to the case 9 is
dissipated fiom the case 9 by the effects of heat transfer, convection, and radiation,
and the remaining heat is conducted to the socket on the lighting apparatus side.
(3) Thermal Load to Circuit Unit
In the LED lamp 1, the globe 7 has a size and shape similar to a glass bulb
of an incandescent light bulb, and the LED module 5 is provided in a substantially
central position inside the globe 7.
[0092]
Thus, (a) the distance between the LED module 5 and the circuit unit 17 is
increased, reducing the thermal load received by the circuit unit 17 from the LEDs 3,
and (b) the distance between the LED module 5 and the case 9 is increased, reducing
the amount of heat accumulated in the case 9 due to heat received fiom the LEDs 3.
Thus, the size of the case 9 can be reduced. On the other hand, the globe 7 (the
envelope volume of the globe 7) can be increased in size, increasing the amount of
heat dissipated from the globe 7.
7. Protrusion Portion for Fixing Insulation Member
(1) Number of Pieces
In the embodiment, the four protrusion portions 101 are formed at regular
intervals in the circumferential direction of the bottomed cylinder portion 19a.
However, it suffices that only one protrusion portion 101 be formed if attention is
paid only to preventing the insulation member 19 falling apart from the mount 13. If
only one protrusion portion 101 is formed, there is a possibility of axial
misalignment between the insulation member 19 and the axis of the mount 13, but
this can be adjusted for by forming larger through-holes for the lead wires 27 and 29,
and the screw 121.
(2) Positions
.--- - -- - (2-1) Positions in Plan View -
In the embodiment, the protrusion portions 101 are formed at 90 degree
intervals in a circumferential direction of the bottomed cylinder portion 19a.
However, for the same reason explained under the above heading "(1) Number of
5 Pieces", the positions of the protrusion portions 101 in plan view is not specifically
limited in this way. Nevertheless, in order to restrict axial misalignment between the
insulation member 19 and the mount 13, positioning at least three protrusion
portions 101 at regular intervals in plan view is desirable.
(2-2) Position in Side View
10 In the embodiment, the protrusion portions 101 are formed closer to an
opening of the bottomed cylinder portion 19a than to the end wall thereof. This is
because, when inserting the insulation member 19 into the mount 13, if the
protrusion portions 101 were formed near the end wall, deformation by the
protrusion portion 101 of the portion of the bottomed cylinder portion 19a near the
15 end wall would be difficult, and therefore insertion of the insulation member 19 into
the mount 13 would be difficult.
[0093]
However, if the protrusion portions 101 are such that the protrusion amount
of the protrusion portions 101 gradually increases with increasing distance fiom the
20 end wall, the protrusion portion 101 may be positioned near the end wall, or may be
elongated from the end wall to the opening of the bottomed cylinder portion 19a.
(3) Shape of Protrusion Portion
(3-1) Overall Shape
In the embodiment, the protrusion portions 101 are formed having a ridge
25 shape and are elongated parallel to the central axis of the bottomed cylinder portion
19a of the insulation member 19. However, the protrusion portions 10 1 may each
have a bump shape (a dot shape). Also, each of the protrusion portions 101 in the
embodiment has a ridge shape that has a constant protrusion amount and width.
3 0
= . .- However, each of the protrusion portions 101 may have a ridge shape that has a
variable protrusion amount and width. Specifically, each of the protrusion portions
101 may have a shape such that the protrusion amount and width of each of the
protrusion portions 101 gradually increases with increasing distance from the end
5 wall.
[0094]
Also, each of the protrusion portions 101 may have an arc shape following
the outer circumferential surface of the bottomed cylinder portion 19a in plan view.
In such a case, each of the protrusion portions 101 may have an inclined surface, and
10 increase in arc as the position of the arc shape approaches the opening of the
bottomed cylinder portion 19a.
(3-2) Cross-Sectional Shape
In the embodiment, a cross-section of each of the protrusion portions 101
before attachment of the insulation member 19 to the mount 13 (the cross-section
15 being taken along a plane orthogonal to the central axis of the insulation member 19,
viewed in a direction of extension of the central axis of the insulation member 19) is
a triangle shape that tapers off as each of the protrusion portions 101 approaches the
mount 13 from the insulation member 19. However, the shape of each of the
protrusion portions 101 in cross-section may be other shapes. Examples of shapes
20 that taper off, other than triangle shapes, include semicircle shapes, semi-elliptical
shapes, trapezoid shapes, and polygonal shapes. Examples of shapes that do not
taper off include square shapes and rectangular shapes.

An explanation is given above based on an embodiment of the present
25 invention, but the present invention is not limited to the above embodiment. For
example, the following modifications are possible.
1. Mount and Extension Member
In the above embodiment, the extension member and the mount are separate
3 1
- -.=,- . - members and-arejoined by the screw, bu$ for example, the extension member and - - C
the mount may be integrated into a single body. Die casting or machining may be
used to form the single body.
[0095]
5 In the above embodiment, the extension member has a rod shape, but the
extension member may have any shape or structure that positions the LEDs (the
LED module) inside the globe.
[0096]
For example, the extension member may have a cone shape or a polygonal
10 pyramid shape, and fiuther, may have a shape that becomes narrower through a
series of steps as an upper part of the extension member is approached. Furthermore,
the extension members may be provided in a plurality. For example, two rod-shaped
extension members may be used to support both end portions of the mounting board
of the LED module in the longitudinal direction of the mounting board (the end
15 portions corresponding to the short sides of the mounting board), or four rod-shaped
extension members may be used to support four corners of the rectangular mounting
board.
[0097]
In the above embodiment, a transverse cross-section of the cylinder portion
20 of the mount has a circular shape, but as long as the extension member attaches to
the cylinder portion and the cylinder portion closes one open end of the case, other
shapes are possible. Examples of other shapes of the transverse cross-section include
elliptical shapes or polygonal shapes.
2. Insulation Member
25 In the above embodiment, the insulation member has a bottomed cylindrical
shape, but as long as the insulation member has a cylindrical portion that can be
inserted into the inside of the cylinder portion of the mount, the insulation member
may have other overall shapes. For example, the insulation member may have other
32
- , ..- a* p overdt shapes, such as a shape ineluding a flat- portion having a flat shape and-a -- - -.
cylinder portion protruding fiom a central area of the flat shape.
[0098]
Also, in the above embodiment, the insulation member has a bottomed
5 cylindrical shape having the end wall as the bottom, but in a case where insulation is
ensured between the cover portion of the mount and the circuit unit, the end wall is
not required.
[0099]
In the above embodiment, the insulation member has a bottomed cylindrical
10 shape, and the end wall is in contact with the cover portion of the mount. Thus,
accuracy when positioning the insulation member with respect to the mount is
increased. On the other hand, to make conduction of heat fiom the mount to the
insulation member more difficult, it suffices that faces of the end wall and the cover
portion are not in surface contact with each other. Note that by providing an upper
15 surface of the end wall with a bump portion contacting the cover portion of the
mount, heat conduction to the insulation member fiom the mount is suppressed,
while maintaining accuracy when positioning the insulation member with respect to
the mount.
3. LED module
20 (1) LED
In the above embodiment, LED elements are used as the light source of the
lamp. However, for example, surface-mount type or shell-type LEDs may be used,
such that each LED element is resin sealed and the LED module is composed of the
mounting board and the LEDs.
25 [OlOO]
In the above embodiment, an example is given in which the LEDs emit blue
light and the fluorescent particles convert blue light to yellow light, but other
combinations are possible. As one example of a different combination, the LEDs
3 3
- may- emit ultra-violet -light and three- types of-fluorescent partick may be used to -
enable the lamp to emit white light: a particle that converts ultra-violet light to red
light, a particle that converts ultra-violet light to blue light, and a particle that
converts ultra-violet light to green light.
[OlOl]
Further, the lamp may be configured to emit white light by using three types
of LED elements: a first type emitting red light, a second type emitting green light,
and a third type emitting blue light, and by mixing the three colors emitted by the
three types of LED elements. Note that the color of light emitted from the LED
module is of course not limited to white, and according to the purpose of the lamp, a
variety of LEDs (including LED elements and surface-mounted LEDs) and
fluorescent particles may be used.
(2) Mounting Board
In the above embodiment, an explanation is given of an example in which
the mounting board has a rectangular shape in plan view. However, the shape of the
mounting board in plan view is not specifically limited in this way. For example, in
plan view the mounting board may have a circular shape, an elliptical shape, a
polygonal shape, etc.
[O 1 021
Also, in the above embodiment, an explanation is given of an example
mounting board which is a board having a small thickness (an area of a side surface
is smaller than an area of an upper surface). However, for example, the mounting
board may be a board having a large thickness or a block shape.
[0 1 031
Note that regardless of the shape, thickness, and form of the mounting board,
the mounting board in the present specification indicates a mount on which the
LEDs (including LED elements and surface-mounted LEDs) are mounted, and that
has a pattern that is electrically connected to the LEDs. Accordingly, the mounting
34
.- . . . * - * . board may have the block shape mentioned- above, or. may be the mmting board - - -
and the extension member pertaining to the embodiment configured as a single
body.
[O 1 041
5 In the above embodiment, the mounting board is formed from
light-transmissive material, but in a case where emitting light backward, in the base
direction, is not required the mounting board may k m e d from material other
than light-transmissive material.
(3) Attachment position
10 The LED module in the above embodiment has a mounting board formed
fiom a light-transmissive material in order to irradiate light backward, in the base
direction, but light may be irradiated backward, in the base direction, by other
methods.
[0105]
As another method, the mounting board may be formed from material that is
not light-transmissive material, and the LEDs may be mounted on both main
surfaces of the mounting board. As yet another method, the mounting board may be
formed fiom material that is not light-transmissive material, the mounting board
may have a spherical shape, a cube shape, etc. (for example, the mounting board
20 may include six insulated boards joined in three-dimensions to form a cube shape),
and the LEDs (including shell-type LEDs and surface-mounted LEDs) may be
mounted on a surface of the mounting board.
(4) Light-Emitting Elements
In the above embodiment and modifications, LEDs are used as the
25 light-emitting elements, but light-emitting elements other than LEDs may be used.
As other light-emitting elements, for example, EL light-emitting elements (including
organic and inorganic) or LD, etc., may be used, or a combination of such
light-emitting elements, including LEDs, may be used.
3 5
4;Globe - - - -; --- -*--5 x-- ... ' -' - . . . , - : - .-- - < .
(1) Form
In the above embodiment, an A-type globe or R-type globe is used, but
other types, such as B-type globes or G-type globes may be used, or globe shapes
5 completely different from the bulb shapes of incandescent light bulbs and light-bulb
shaped fluorescent lamps may be used.
[0 1 061
Also, in the above embodiment, the globe is formed as a single body, but,
for example, the globe may be a plurality of pieces that are produced separately and
10 assembled as one globe. In such a case, every piece does not have to be made from
the same material, and, for example, the globe may be a combination of pieces
composed of resin and pieces composed of glass. Note that the use of a globe
assembled from a plurality of pieces allows the use of an LED module that is larger
than the opening at the lower end of the globe.
15 [0107]
The globe may be light-transmissive such that the interior of the globe is
visible, or may be semitransparent such that the interior of the globe is not visible. A
semitransparent globe, for example, may be implemented by applying a difhsion
layer having a primary component such as calcium carbonate, silica, white pigment,
20 etc., to an inner surface of the globe, and applying a treatment for roughening an
inner surface of the globe (for example, a blast treatment).
(2) Size
In the above embodiment, an explanation is not specifically given of a ratio
of a length of the globe to a total length of the lamp. Here, a globe ratio means a
25 total length of the globe relative to the total length of the lamp. The total length of
the globe is a length of the central axis of a portion of the globe that is exposed to
outside air.
[0108]
The globe ratio is preferably equal to or greater than 0.54. If the globe ratio
is less than 0.54, a surface area of the portion of the globe that is exposed to outside
air is small, and a s&icient heat dissipation characteristic of the globe cannot be
obtained. Also, if the globe size is decreased, the distance between the LED module
and the circuit unit is decreased, and when the lamp is lit, heat received by the
i circuit unit fiom the LED module is increased, affecting the circuit unit.
(3) Material
In the above embodiment, a glass material is used as the material of the
globe, but other light-transmissive materials, for example a resin material, may be
used.
5. Case
In the above embodiment, the envelope that includes the globe and the case
has a shape similar to an incandescent light bulb, but the envelope may have other
shapes. Also, in the above embodiment explanation was not specifically given
regarding an outer surface of the case, but, for example, in order to increase an
envelope volume of the case, heat dissipation grooves and heat dissipation fins may
be provided on the outer surface of the case.
6. Envelope
In the above embodiment, a particular treatment is not applied to the outer
circumferential surface of the envelope that includes the globe and the case.
However, coating material having a desired function may be applied to all or part of
the outer circumferential surface of the envelope. Examples of such fimctions
include a shatter prevention function, an ultraviolet light shielding function, an
anti-fogging function, etc.
[0 1 091
A shatter prevention function prevents scattering of fragments of the
envelope if the envelope is damaged for any reason. As the coating material, for
example, urethane resin and silicone resin, etc., may be used. Note that the coating
37
material having a shatter prevention fonctian may be appEM-to the globe only (a
part of the envelope).
[Ol lo]
An ultraviolet light shielding function prevents exposure of the envelope to
ultraviolet light, and thus prevents changes in color and reduction in strength of the
envelope. As the coating material having the ultraviolet light shielding function, for
example, polyolefm-type resin, etc., may be used.
[Olll]
An anti-fogging function prevents fogging of primarily the globe (a part of
the envelope) when the lamp is used in a high humidity ambient atmosphere. As the
coating material having the anti-fogging function, for example, acrylic resin, etc.,
may be used.
7. Base
In the above embodiment, an Edison-type base is used, but other types of
bases, for example pin-type bases (specifically, G-type bases such as GY and GX)
may be used.
[0112]
Also, in the above embodiment, the base is attached to the case by a female
thread of the shell portion of the base being screwed into the male thread of the case,
but the base may be attached to the case by another method. As another method,
attaching by adhesive, attaching by caulking, attaching by pressure, etc., or attaching
by a combination of two or more of the above methods is possible.
8. LED position
In the present embodiment, the position of the LEDs inside the globe
corresponds to the position of a filament of an incandescent light bulb. Specifically,
the globe has a shape similar to an incandescent light bulb (A-type), and has a
spherical portion and a cylindrical portion. Further, the LEDs (the LED module) are,
if the globe shape corresponds to an A-type incandescent light bulb, arranged in a
38
celrtrakakpesitisn of the spherical portion. - - - * - -'-
[0113]
The position described above is a position relative to the globe and is the
central position of the spherical portion. However, from the base, the distance fi-om
an end tip of the base (an end tip of the eyelet portion) to the position of the LEDs is
substantially the same as the distance fiom an end tip of a base of an incandescent
light bulb to a filament of the incandescent light bulb.
[0114]
However, the structure of the present invention is not limited to a globe that
has an A-type shape as described above. For example, the globe may have a
cylindrical shape that is closed at an end portion opposite the base. In such a case,
the LEDs may be positioned at a focal point of a reflector of a lighting apparatus to
which the lamp is attached, or a light-emission center of a lamp that the lamp is
replacing (for example, a krypton bulb, a fluorescent bulb-type lamp, etc.).
9. Lighting Device
In the above embodiment and elsewhere, explanation is primarily given of
the LED lamp, but the following is an explanation of a lighting device that uses the
LED lamp. In other words, the present lighting device includes at least one of the
varieties of the lamp described above and a lighting apparatus that attaches and
lights up the lamp.
[0115]
In the LED lamp explained under the heading Background Art (hereafter,
"conventional LED lamp"), the case is used as a heat dissipation part, and therefore
the case is large. In such a case, the LEDs are farther fi-om the base than a filament is
fiom a base in an incandescent light bulb. In other words, the position of the LEDs
in the conventional LED lamp seen as a whole (distance from the base) is different
fi-om the position of the filament in an incandescent lamp seen as a whole (distance
from the base).
L . 7 5 . - . {0116] - , . -. - +-
When the conventional LED lamp is used with a reflector that is included in
a lighting apparatus that an incandescent light bulb was attached to, for example
when using the conventional LED lamp as a downlight, problems occur such as an
5 annular shadow on a surface irradiated by the conventional LED lamp. In other
words, due to differences in light source position between the conventional LED
lamp and a conventional incandescent light bulb, problems occur with light
distribution characteristics, etc.
[0117]
Fig. 11 is a schematic view of a lighting device 201 pertaining to another
embodiment.
[0118]
The lighting device 201 is used, for example, while attached to a ceiling
202.
15 [0119] -
As shown in Fig. 1 1, the lighting device 201 includes the LED lamp 1 and a
lighting apparatus 203 to which the LED lamp 1 is attached. The lighting apparatus
203 lights up and turns off the LED lamp 1.
[O 1201
20 The lighting apparatus 203 includes, for example, an equipment main body
205 that is attached to the ceiling 202 and a cover 207 that is attached to the
equipment main body 205 and covers the LED lamp 1. The cover 207 in the present
example is an open-type cover that has a reflection film 21 1 on an inner surface
thereof. The reflection film 21 1 reflects light emitted fiom the LED lamp 1 in a
25 predetermined direction (downward, in the present example).
[0121]
The equipment main body 205 includes a socket 209 to which the base 11
of the LED lamp 1 is attached (screwed into). Electricity is supplied to the LED
40
lamp 1 via the socket 209.
[O 1221
In the present example, since the position of the LEDs 3 (the LED module
5) of the LED lamp 1, which is attached to the lighting apparatus 203, is similar to
the position of a filament of an incandescent light bulb, a light-emission center of
the LED lamp 1 is positioned similarly to a light-emission center of the incandescent
light bulb.
[0 1231
Thus, even when the LED lamp 1 is attached to the lighting apparatus 203,
to which the incandescent light bulb was attached, since the position of the
light-emission center of the LED lamp 1 and the incandescent light bulb is similar,
problems such as an annular shadow on a surface irradiated by the LED lamp 1 are
less likely to occur.
[0 1 241
Note that the above-described lighting apparatus is one example, and the
lighting apparatus 203 may, for instance, not have the cover 207, which is an open
type, and instead have a closed type cover. The lighting apparatus 203 may also
orientate the LED lamp 1 sideways (an orientation where the central axis of the lamp
is horizontal), or obliquely (an orientation where the central axis of the lamp is
oblique, relative to the central axis of the lighting apparatus), and light up the LED
lamp 1.
[0 1251
Also, the lighting device in the present example includes the lighting
apparatus 203 that is a direct attachment type that, in a state of contact with a ceiling
or wall, is attached to the ceiling or the wall. However, the lighting apparatus 203
may be an embedded type that, in a state of being embedded in a ceiling or wall, is
attached to the ceiling or the wall, or the lighting apparatus 203 may be a suspended
type that is suspended from a ceiling by an electric cable of the lighting apparatus
41
-203.
[0 1261
Furthennore, in the present example, the lighting apparatus lights up one
LED lamp (the LED lamp 1) that is attached thereto, but the lighting apparatus may
5 light up a plurality, for example three, LED lamps attached thereto.
[Industrial Applicability]
[0 1271
The present invention provides an LED lamp that has a simple structure and
that is easy to assemble.
10 [Reference Signs List]
[0128]
1 LED lamp
3 LEDs
5 LED module
7 globe
9 case
11 base
13 mount
1 3 a cylinder portion
1 3 b cover portion
15 extension member
17 circuit unit
19 insulation member
19a bottomed cylinder portion
19b flange portion
10 1 protrusion portion

CLAIM
1. A lamp including: an envelope formed by a globe and a case; a light emitting
element disposed inside the envelope; and a circuit unit disposed inside the envelope
5 and configured to light the light-emitting element, wherein
the light-emitting element is attached to an extension member that extends
fkom a mount into the globe, the mount closing an opening at one end of the case,
the circuit unit being disposed inside the case, which is closed by the mount,
the mount is made of an electrically conductive material, and an insulation
10 member is disposed inside the case to insulate the circuit unit fkom the mount,
the mount has a cylinder portion and a cover portion that closes one end of
the cylinder portion, and the extension member is mounted on the cover portion of
the mount, and
the insulation member has a cylindrical portion that is inserted into the
15 cylinder portion of the mount and has a protrusion portion that is formed on an outer
circumference of the cylindrical portion and that protrudes toward the mount, the
insulation member being attached to the mount by the protrusion portion pressing on
an inner surface of the cylinder portion of the mount.
20 2. The lamp of claim 1, wherein
the protrusion portion is a plurality of protrusion portions disposed in a
circumferential direction of the cylindrical portion, each protrusion portion being
elongated in a direction parallel to the central axis of the cylindrical portion.
25 3. The lamp of claim 1, wherein
the protrusion portion is a plurality of protrusion portions disposed in a
circumferential direction of the cylindrical portion, each protrusion portion having a
bump shape.
43
-
4. The lamp of any one of claims 1 to 3, wherein
the insulation member has an end wall disposed at one of two ends of the
cylindrical portion, and
5 the protrusion portion is disposed closer to the other one of the two ends of
the cylindrical portion than the one end at which the end wall is disposed.
5. The lamp of claim 4, wherein
the cover portion of the mount and the end wall of the insulation member
10 are in contact with each other,
a through hole passes through the cover portion of the mount and the end
wall of the insulation member, and
the extension member is fured by a screw member, which has a head portion
disposed inside the cylindrical portion of the insulation member and a screw portion
15 that passes through the through hole.
Dated this 24/12/20 13
NEHAS ASTAVA)
OF REMFRY & SAGAR
ATTORNEY FOR THE AF'PLICANT[S]