Information
-
Patent Grant
-
6488538
-
Patent Number
6,488,538
-
Date Filed
Monday, October 23, 200023 years ago
-
Date Issued
Tuesday, December 3, 200221 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Sircus; Brian
- Le; Thanh-Tam
Agents
- Parkhurst & Wendel, L.L.P.
-
CPC
-
US Classifications
Field of Search
US
- 439 226
- 439 611
- 439 612
- 439 615
- 439 620
- 313 31801
- 313 31803
- 313 31804
- 313 31809
- 313 3181
- 313 31812
- 315 58
-
International Classifications
-
Abstract
The present invention provides a tube lamp and its manufacturing method which allow a lighting circuit and a shell to be easily and reliably connected together, which enable automation of a step of connecting the lighting circuit and the shell together, and which require low costs while achieving a high production efficiency. The tube lamp includes a case having a shell at an end thereof, and a lighting circuit housed in the case and having a printed circuit board with a circuit part mounted thereon, wherein the shell and the lighting circuit are connected together without leads.
Description
FIELD OF THE INVENTION
The present invention relates to a tube lamp and its manufacturing method.
BACKGROUND OF THE INVENTION
A conventional tube lamp, for example, a bulb type fluorescent lamp comprises an enclosure comprising a globe
1
and a case
37
, a fluorescent tube
4
, a lighting circuit
38
for lighting the fluorescent tube
4
, the fluorescent lamp and the lighting circuit both being housed in the enclosure, as shown in FIG.
16
.
The case
37
has a base
41
screwed on one end thereof and having an eyelet
39
and a shell
40
.
The lighting circuit
38
has two leads
42
and
43
for supplying power. One
42
of the leads is led out from a through-hole formed in the eyelet
39
and is electrically connected to an outer surface of the eyelet
39
by means of soldering.
The other lead
43
is led to an exterior of the case
37
and electrically connected to an outer surface of the shell
40
by means of soldering.
In such a conventional tube lamp, however, the lighting circuit
38
and the base
41
are connected via the leads
42
and
43
, that is, the conventional tube lamp requires the following operations: The one
42
of the leads is straightened and passed through the through-hole
44
in the eyelet
39
, the other lead
43
is bent and led to the exterior of the case
37
, and the leads
42
and
43
are then brought into contact with the outer surface of the shell and their unwanted portions are cut off for the soldering. These operations must be manual, thereby reducing productivity and increasing costs.
SUMMARY OF THE INVENTION
The present invention is provided to solve these problems, and it is an object thereof to provide a tube lamp and its manufacturing method which allow a lighting circuit and a shell to be easily and reliably connected together, which enable automation of a step of connecting the lighting circuit and the shell together, and which require low costs while achieving a high production efficiency.
A tube lamp according to the present invention comprises a case including a base portion having a shell at an end thereof, and a lighting circuit housed in the case and comprising a printed circuit board with a circuit part mounted thereon, the shell and the lighting circuit being connected together without leads.
Additionally, a tube lamp manufacturing method according to the present invention manufactures a tube lamp comprising a case including a base portion having a shell at an end thereof, and a lighting circuit housed in the case and comprising a printed circuit board with a circuit part and terminals mounted thereon, the shell and the terminals being connected together, the method comprising connecting the terminals to the shell at the same time when the lighting circuit is housed in the case.
The tube lamp and its manufacturing method eliminate the needs for leads and soldering thereof to enable the shell and the lighting circuit to be easily and reliably connected together, enable automation of a step of connecting the lighting circuit and the shell together instead of depending on manual operations, improve production efficiency due to the omission of the soldering step, and reduces costs because of a reduction in maintenance costs for facilities required for the soldering step and in material costs for leads, solders, and the like. The omission of solders also contributes to environment protection.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a partly cutaway front view of a bulb type fluorescent lamp according to a first embodiment of the present invention;
FIG. 2
is a perspective view of a lighting circuit used in this bulb type fluorescent lamp, showing its integral part in an enlarged view;
FIG. 3
is a sectional view of this bulb type fluorescent lamp, showing its integral part in an enlarged view;
FIG. 4
is a partly cutaway front view showing a variation of this bulb type fluorescent lamp;
FIG. 5
is a partly cutaway front view of a bulb type fluorescent lamp according to a second embodiment of the present invention;
FIG. 6
is a sectional view of this bulb type fluorescent lamp, showing its integral part in an enlarged view;
FIG. 7
is a perspective view of a lighting circuit used in this bulb type fluorescent lamp, showing its integral part in an enlarged view;
FIG. 8
is a partly cutaway front view of a bulb type fluorescent lamp according to a third embodiment of the present invention;
FIG. 9
is a sectional view of this bulb type fluorescent lamp, showing its integral part in an enlarged view;
FIG. 10
is a perspective view of a lighting circuit used in this bulb type fluorescent lamp, showing its integral part in an enlarged view;
FIG. 11
is a partly cutaway front view of a bulb type fluorescent lamp according to a fourth embodiment of the present invention;
FIG. 12
is a sectional view of this bulb type fluorescent lamp, showing its integral part in an enlarged view;
FIG. 13
is a perspective view of a lighting circuit used in this bulb type fluorescent lamp, showing its integral part in an enlarged view;
FIG. 14
is a perspective view of a lighting circuit used in a bulb type fluorescent lamp according to a fifth embodiment of the present invention, showing its integral part in an enlarged view;
FIG. 15
is a perspective view of a lighting circuit used in a bulb type fluorescent lamp according to a sixth embodiment of the present invention, showing its integral part in an enlarged view; and
FIG. 16
is front sectional view of a conventional bulb type fluorescent lamp.
DESCRIPTION OF THE EMBODIMENTS
The embodiments of the present invention will be described below with reference to the drawings.
A bulb type fluorescent lamp of rated power 13 W according to a first embodiment of the present invention has a length of 120 mm and a maximum outer diameter of 60 mm, and comprises an enclosure formed of a transmissive globe
1
and a resin case
2
, a fluorescent tube
4
in which three substantially U-shaped tubes
3
each having an outer diameter of 11 mm are bridged together to form a single discharge path, a lighting circuit
5
for lighting the fluorescent lamp
4
, and a holder
6
for holding one end of the fluorescent tube
4
and also holding the lighting circuit
5
opposite to the fluorescent tube
4
, as shown in FIG.
1
.
The case
2
has a base portion
7
formed at one end thereof and which is inserted into a socket of a luminaire. The base portion
7
has an eyelet
8
and a shell
9
both coming in electric contact with the socket. The base portion
7
also has an eyelet receiving section
10
at a tip portion thereof in which the eyelet
8
is fitted.
The eyelet receiving section
10
has four locked portions
11
(only two are shown in
FIG. 1
) in an inner surface thereof in which a locking portion
17
of the eyelet
8
, described later, is locked.
The fluorescent tube
4
has electrodes (not shown) each located at a corresponding one of opposite ends thereof. The fluorescent tube
4
also has predetermined amounts of mercury and rare gas sealed inside.
The lighting circuit
5
comprises a T-shaped printed circuit board
12
with a circuit part
13
mounted thereon. The printed circuit board
12
is located inside the case
2
parallel with a central axis X thereof with a leg part of the character T up.
The printed circuit board
12
also has two terminals
14
and an eyelet
8
mounted thereon as also shown in FIG.
2
.
In
FIG. 2
, the circuit part on the printed circuit board
12
is omitted.
The terminal
14
comprises an L-shaped copper alloy plate of thickness 0.1 to 0.5 mm.
The terminal
14
has its end inserted into a gap
15
formed between the shell
9
and a depression formed by cutting a resin portion off from the base portion
7
so that this end is in electric contact with an inner surface of the shell
9
within the gap
15
, as shown in FIG.
3
. The term “electric contact” refers to a means for “electric connection”.
For a reliable electric contact, the shell
9
and the terminals
14
are preferably connected together by means of laser welding or a conductive adhesive or paste.
The terminals
14
each have a cut and raised portion
16
formed by cutting a substantially U-shaped portion out therefrom as shown in FIG.
2
. Further, the cut and raised portion
16
is bent inward and acts as a plate spring. As shown in
FIG. 3
, by bringing the cut and raised portion
16
, having a spring property, into pressure contact with the inner surface of the case
2
, the terminal
14
can be pushed toward the shell
9
so as to reliably come in electric contact therewith.
It may be contemplated that the terminal
14
entirely has the spring property so as to be pushed toward the shell
9
so as to reliably come in electric contact therewith independently of the spring property of the cut and raised portion
16
. In this case, however, a connection between the printed circuit board
12
and the terminal
14
is subjected to a load and fatigued, so that the terminals
14
may slip out from the printed circuit board
12
.
On the other hand, when the terminals
14
each have the cut and raised portion
16
formed at its end, the above described load is exerted on the cut and raised portion
16
, which is part of the terminal
14
. Consequently, the load on the connection between the printed circuit board
12
and the terminal
14
decreases to restrain the connection from being fatigued, thereby preventing the terminals
14
from slipping out from the printed circuit board
12
.
Although
FIG. 3
shows one of the terminals
14
, the other terminal
14
has the same configuration.
The eyelet
8
is obtained by pressing a plate of thickness 0.3 to 1 mm into a recessed form as shown in FIG.
2
.
In addition, a head portion of the eyelet
8
, that is, a portion of the eyelet
8
which is exposed from the case
2
has such a projecting shape that it is gently expanded. This shape enables the eyelet
8
and the socket of the luminaire (not shown) to be reliably electrically connected together.
The eyelet
8
has four locking portions
17
(only two are shown in
FIG. 2
) formed by cutting and raising part of a side surface of the eyelet into a U shape. The locking sections
17
are each slightly bent outward relative to the eyelet
8
. The eyelet
8
is fitted in the eyelet receiving section
10
in such a manner that the locking portions
17
are locked in corresponding locked portions
11
of the eyelet receiving section
10
. Consequently, when the base portion
7
is mounted in the socket of the luminaire (not shown), the eyelet
8
is prevented from slipping out from the eyelet receiving section
10
when pushed into the case
2
with the lighting circuit
5
, thereby precluding an inappropriate contact between the eyelet
8
and the socket (not shown).
Next, a method for manufacturing such a bulb type fluorescent lamp will be explained.
First, the fluorescent tube
4
is attached to the holder
6
in a conventional manner using an adhesive (not shown).
The lighting circuit
5
with the eyelet
8
, the circuit part
13
, and the terminals
14
mounted thereon is mounted in the holder
6
with the fluorescent tube
4
attached thereto in such a manner that the lighting circuit
5
extends perpendicularly to the holder
6
.
The lighting circuit
5
is subsequently housed in the case
2
. At this point, the eyelet
8
is internally inserted and fitted in the eyelet receiving section
10
, and the ends of the terminals
14
, that is, the cut and raised portions
16
are inserted into the gap
15
formed between the depression and the shell
9
so that the shell
9
and the terminals
14
are electrically connected together.
When the eyelet
8
is fitted in the eyelet receiving section
10
, the locking portions
17
of the eyelet
8
are bent inward of the eyelet
8
and then outward thereof at the locked portions
11
due to their elasticity, that is, the locking portions
17
finally return to their original states and are thus locked in the locked portions
11
.
Finally, the globe
1
is fixed to the case
2
and the holder
6
using an adhesive (not shown). The bulb type fluorescent lamp is manufactured in this manner.
This embodiment eliminates the needs for leads and soldering thereof to enable the lighting circuit
5
and the shell
9
to be easily and reliably connected together and enable automation of a step of connecting the lighting circuit
5
and the shell
9
together instead of depending on manual operations. Production efficiency can also be improved due to the omission of the soldering step. Costs can also be reduced because of a reduction in maintenance costs for facilities required for the soldering step and in material costs for leads, solders, and the like. The omission of solders also contributes to environment protection.
In the first embodiment, the cut and raised portions
16
are bent inward, but similar effects are obtained if the cut and raised portions
16
are bent outward and are in pressure contact with the inner surface of the shell
9
.
Additionally, in the first embodiment, the printed circuit board
12
is located inside the case
2
parallel with the central axis X thereof with the leg part of the character T up, but similar effects are obtained if, for example, a substantially disc-shaped printed circuit board
12
a
is located inside the case perpendicularly to the central axis X thereof as shown in FIG.
4
. In the example shown in
FIG. 4
, however, an eyelet
39
is shaped like a disc as in the prior art.
Next, a bulb type fluorescent lamp of rated power 13 W according to a second embodiment of the present invention has the same configuration as the bulb type fluorescent lamp of rated power 13 W according to the first embodiment of the present invention except that the printed circuit board
12
has two terminals
18
mounted thereon and each comprising a substantially U-shaped copper alloy plate of thickness 0.1 to 0.5 mm, the terminals
18
being in electric contact with the inner surface of the shell
9
through corresponding notches
20
formed in the case
19
as shown in FIG.
5
.
In
FIG. 5
, reference numeral
19
a
denotes a base portion of the case
19
and reference numeral
21
denotes a lighting circuit.
The end of each of the terminals
18
has a projecting shape in a portion thereof that is in substantially electric contact with the shell
9
. This shape ensures an electric contact between the shell
9
and the terminal
18
.
In addition, the end of each of the terminals
18
has the spring property. This enables the terminal
18
to come in pressure contact with the inner surface of the shell
18
to ensure an electric contact between the shell
9
and the terminal
18
.
In
FIG. 6
, one of the terminals
18
is shown, but the other terminal
18
has the same configuration.
Additionally, the end of each of the terminals
18
is divided into two, which are each electrically contacted with the shell (not shown). This configuration can increase the number of electric contacts between the shell
9
and the terminal
18
to further reliably contact the shell
9
and the terminal
18
with each other, thereby allowing the shell
9
and the terminal
18
to be more reliably connected together.
A plate-shaped connection
18
a
is provided between the terminals
18
to reduce a load on the connection between the printed circuit board
12
and the terminal
18
.
In
FIG. 7
, the circuit part on the printed circuit board is omitted.
The notches
20
are each formed by cutting out part of a resin portion at an end of the base portion
19
a
opposed to the eyelet
8
.
Like the bulb type fluorescent lamp of rated power 13 W according to the first embodiment, this embodiment eliminates the needs for leads and soldering thereof to enable the shell
9
and the lighting circuit
21
to be easily and reliably connected together and enable automation of a step of connecting the shell
9
and the lighting circuit
21
together instead of depending on manual operations. Production efficiency can also be improved due to the omission of the soldering step. Costs can also be reduced because of a reduction in maintenance costs for facilities required for the soldering step and in material costs for leads, solders, and the like. The omission of solders also contributes to environment protection.
Next, a bulb type fluorescent lamp of rated power 13 W according to a third embodiment of the present invention has the same configuration as the bulb type fluorescent lamp of rated power 13 W according to the first embodiment of the present invention except that two sandwiching terminals
22
are mounted on the printed circuit board
12
and that part of the shell
23
penetrates a case
24
to extend therethrough in a fashion being sandwiched between the sandwiching terminals
22
, as shown in
FIGS. 8 and 9
.
In
FIGS. 8 and 9
, reference numeral
25
denotes a lighting circuit. In
FIG. 9
, one of the terminals
22
is shown, but the other terminal
22
has the same configuration.
FIG. 10
shows the lighting circuit
25
, comprising the eyelet
8
and the two sandwiching terminals
22
mounted on the printed circuit board
12
. However, the circuit part on the printed circuit board
12
is omitted.
Like the bulb type fluorescent lamps of rated power 13 W according to the first and second embodiments, this embodiment eliminates the needs for leads and soldering thereof to enable the shell
24
and the lighting circuit
25
to be easily and reliably connected together and enable automation of a step of connecting the shell
24
and the lighting circuit
25
together instead of depending on manual operations. Production efficiency can also be improved due to the omission of the soldering step. Costs can also be reduced because of a reduction in maintenance costs for facilities required for the soldering step and in material costs for leads, solders, and the like. The omission of solders also contributes to environment protection.
Next, a bulb type fluorescent lamp of rated power 13 W according to a fifth embodiment has the same configuration as the bulb type fluorescent lamp of rated power 13 W according to the first embodiment of the present invention except that two terminals
26
with bent ends are mounted at the eyelet
8
side end on the printed circuit board
12
and extend through corresponding through-holes
28
formed in the case
27
before coming in electric contact with the inner surface of the shell
9
.
In
FIGS. 11 and 12
, reference numeral
29
denotes a base portion of a case
27
, and in
FIG. 12
, reference numeral
30
denotes a lighting circuit.
The end of each of the terminals
26
is pressure contact with the inner surface of the shell
9
and with a resin portion of the base portion
29
due to the spring property of this end. This ensures that the shell
9
and the terminal
26
are electrically contacted together to reduce the load on the connection between the printed circuit board
12
and the terminal
26
.
The through-holes
28
are each formed by cutting out part of a resin portion at the eyelet
8
side end.
FIG. 13
shows the lighting circuit
30
comprising the eyelet
8
and the two terminals
26
mounted on the printed circuit board
12
. In
FIG. 13
, however, the circuit part on the printed circuit board
12
is omitted.
Like the bulb type fluorescent lamps of rated power 13 W according to the above described embodiments, this embodiment eliminates the needs for leads and soldering thereof to enable the shell
9
and the lighting circuit
30
to be easily and reliably connected together and enable automation of a step of connecting the shell
9
and the lighting circuit
30
together instead of depending on manual operations. Production efficiency can also be improved due to the omission of the soldering step. Costs can also be reduced because of a reduction in maintenance costs for facilities required for the soldering step and in material costs for leads, solders, and the like. The omission of solders also contributes to environment protection.
In addition, the bent end of each of the terminals
26
can increase the contact area between the shell
9
and the terminal
26
, thereby ensuring the electric contact between the shell
9
and the terminal
26
.
Furthermore, although not shown, the end of each of the terminals
26
can be divided into two similarly to the end
18
shown in
FIG. 6
, thereby ensuring the electric contact between the shell
9
and the terminal
26
.
Next, a bulb type fluorescent lamp of rated power 13 W according to a fifth embodiment has the same configuration as the bulb type fluorescent lamp of rated power 13 W according to the first embodiment of the present invention except that terminals
31
each have an inward folded portion
32
formed at a tip portion thereof instead of the cut and raised portion
16
, as shown in FIG.
14
.
In
FIG. 14
, reference numeral
33
denotes a lighting circuit and the circuit part on the printed circuit board
12
is omitted.
Although not shown, the folded portions
32
are each inserted into the gap
15
formed between the case
2
and the shell
9
as in
FIG. 3
, so as to come in pressure contact with the inner surface of the case
2
for electric contact. Additionally, due to its spring property, the folded portion
32
ensures the electric contact between the shell
9
and the terminal
31
while reducing the load on the connection between the printed circuit board
5
and the terminal
31
.
The folded portion
32
may be folded outward so as to come in pressure contact with the inner surface of the case
2
instead of the shell
9
for electric contact.
Like the bulb type fluorescent lamps of rated power 13 W according to the above described embodiments, this embodiment eliminates the needs for leads and soldering thereof to enable the shell
9
and the lighting circuit
33
to be easily and reliably connected together and enable automation of a step of connecting the shell
9
and the lighting circuit
33
together instead of depending on manual operations. Production efficiency can also be improved due to the omission of the soldering step. Costs can also be reduced because of a reduction in maintenance costs for facilities required for the soldering step and in material costs for leads, solders, and the like. The omission of solders also contributes to environment protection.
Next, a bulb type fluorescent lamp of rated power 13 W according to a sixth embodiment has the same configuration as the bulb type fluorescent lamp of rated power 13 W according to the first embodiment of the present invention except that terminals
34
each have an expanded portion
35
formed at an end thereof which has a projecting cross section and extends outward about 0.5 mm, as shown in FIG.
15
.
In
FIG. 15
, reference numeral
36
denotes a lighting circuit and the circuit part on the printed circuit board
12
is omitted.
Although not shown, the expanded portions
35
are each inserted into the gap
15
formed between the case
2
and the shell
9
as in
FIG. 3
, so as to come in pressure contact with the inner surface of the shell
9
for electric contact.
The expanded portion
35
may be expanded inward so as to come in pressure contact with the inner surface of the case
2
instead of the shell
9
for electric contact.
Like the bulb type fluorescent lamps of rated power 13 W according to the above described embodiments, this embodiment eliminates the needs for leads and soldering thereof to enable the shell
9
and the lighting circuit
36
to be easily and reliably connected together and enable automation of a step of connecting the shell
9
and the lighting circuit
36
together instead of depending on manual operations. Production efficiency can also be improved due to the omission of the soldering step. Costs can also be reduced because of a reduction in maintenance costs for facilities required for the soldering step and in material costs for leads, solders, and the like. The omission of solders also contributes to environment protection.
In the above embodiments, the two terminals
14
,
18
,
22
,
26
,
31
, or
34
are mounted on the printed circuit board
12
. If at least one of the terminals
14
,
18
,
22
,
26
,
31
, or
34
is mounted on the printed circuit boar
12
, it can be reliably electrically connected with the shell
9
or
23
. To improve the reliability, two or more of these terminals are preferably mounted on the printed circuit board
12
.
Alternatively, in the second to sixth embodiments, similar effects are obtained if the printed circuit board
12
a
is located perpendicularly to the central axis of the case
19
,
24
, or
27
as in the first embodiment shown in FIG.
4
.
Furthermore, the above embodiments have been described in conjunction with the bulb-type fluorescent lamp. The present invention, however, is not limited to this but is applicable to general incandescent lamps, reflector type lamps, high-voltage discharge lamps, or the like.
Claims
- 1. A tubular bulb comprising:a case including a base portion at an end of the case, the base portion including a shell, and a lighting circuit housed in said case, said circuit comprising a printed circuit board with a circuit part and terminals mounted on the circuit board, said terminals for sliding and electric engagement with said shell, wherein said shell and said lighting circuit are connected together without leads.
- 2. The tubular bulb according to claim 1, wherein an end of each of said terminals is located in a gap between said case and said shell.
- 3. The tubular bulb according to claim 2, wherein each of said terminals has a cut and raised portion at an and thereof, the cut and raised portion in pressure contact with said case or said shell.
- 4. The tubular bulb according to claim 2, wherein said terminal has a folded portion at a tip portion thereof, said folded portion being in pressure contact with said case or said shell.
- 5. The tubular bulb according to claim 2, wherein said terminal has an expanded portion with a projecting cross section at an end thereof, said expanded portion being in pressure contact with said case or said shell.
- 6. The tubular bulb according to claim 1, wherein an end of said terminal is in locking engagement with said shell through a notch or a through-hole in said case.
- 7. The tubular bulb according to claim 1, wherein said terminals each comprise a sandwiching terminal, and said shell partly extends into the case and is at least partly seated in said sandwiching terminals.
- 8. A method for manufacturing a tubular bulb comprising:providing a case having a base portion at an end of the case, the base portion including a shell, a lighting circuit housed in said case, the lighting circuit comprising a printed circuit board with a circuit part and terminals mounted on the circuit board, said shell and said lighting circuit being electrically connected together, and sliding simultaneously said terminals into electric engagement with said shell, thereby mounting said lighting circuit in said case.
Priority Claims (1)
Number |
Date |
Country |
Kind |
11-311996 |
Nov 1999 |
JP |
|
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