JPH07176202A - Bulb-form fluorescent lamp - Google Patents

Abstract

PURPOSE:To obtain a bulb-form fluorescent lamp which can radiate the heat in a good condition without heating a circuit substrate, when a transistor is mounted on the circuit substrate. CONSTITUTION:Inside a cover wherein a base 3 is provided at one end and a bent form fluorescent lamp 20 is installed at the other end, a high-frequency lighting circuit part mounted on a circuit substrate 40 is housed. In this bulb form fluorescent lamp, the high-frequency circuit part mounted on the circuit substrate 40 has a flat transistor 521. This flat transistor 521 is laid on the circuit substrate 40, and a clearance 42 is secured between the flat transistor 521 and the circuit substrate 40. Since the clearance 42 is secured between the transistor 521 and the circuit substrate 40 in this way, the heat of the transistor 521 is not transmitted directly to the circuit substrate 40.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light bulb type fluorescent lamp in which a high frequency lighting circuit component mounted on a circuit board is housed in a cover having a base at one end and a bent fluorescent lamp at the other end. Regarding light lamps.

[0002]

2. Description of the Related Art Recently, one end of a cover is provided with a screw type base for an incandescent lamp, and the other end is U-shaped, W-shaped,
There is a commercially available fluorescent lamp device in which a bending fluorescent lamp such as a saddle type is attached and the lighting circuit parts are housed in the cover. There is also provided a fluorescent lamp device having a structure in which the other end of the cover is closed by a partition board or the lamp is covered with a globe. This type of fluorescent lamp device has circuit components for maintaining the lighting of the fluorescent lamp in the cover, so it is compatible with incandescent light bulbs and can be used in place of incandescent light bulbs to save energy. It can be used as a light source, and is therefore called a bulb-type fluorescent lamp.

By the way, as a lighting circuit component housed in the cover, a ballast is conventionally known, but the ballast is heavy and generates a lot of heat during operation. There are problems such as inefficiency.

Recently, in place of such a ballast,
A means for lighting the lamp by high frequency is adopted.
According to the high frequency lighting method, since high frequency power is supplied to the filament, there is an advantage that the electrode loss during lighting is small and the light emission efficiency is high. Therefore, it has a merit that it is light in weight and generates less heat than a ballast.

As shown in FIG. 5, the high frequency lighting circuit includes a smoothing circuit 51 connected to the commercial power source 50, a drive circuit 52 including a high frequency oscillation circuit (inverter), a start timer circuit 53 and the like. The smoothing circuit 51
Is composed of a rectifier 511, an electrolytic smoothing capacitor 512, etc., and the inverter drive circuit 52 uses field effect transistors 521, 521, an oscillation transformer 522, etc. as main components. Such high frequency lighting circuit components 511, 512, 521, 521, 52
2 and the like are mounted on a circuit board and housed in a cover.

[0006]

When the high-frequency lighting circuit component as described above is placed upright on the circuit board, a predetermined height is required, which makes it difficult to fit the component in the cover and also to route the wiring. Get in the way. For this reason, there is a demand to place some of the components on the circuit board.

However, among the above-mentioned components, transistors, particularly field effect transistors (FETs) 31, 31 are components that generate a large amount of heat during operation, and such FETs are laid down along the circuit board and in a close contact posture. If you place it with, there is a risk that the circuit board will be heated and damaged.
There is a concern that the heat dissipation of the ET itself will be blocked by the circuit board and the temperature of the FET will rise excessively.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a bulb-type fluorescent lamp which can satisfactorily radiate heat without heating the circuit board when mounting the transistor on the circuit board. .

[0009]

According to a first aspect of the present invention, a high frequency lighting circuit component mounted on a circuit board is housed in a cover having a base at one end and a bent fluorescent lamp at the other end. In the bulb-type fluorescent lamp, the high-frequency lighting circuit component mounted on the circuit board is provided with a plate-shaped transistor, the transistor is laid down along the circuit board, and a gap is provided between the transistor and the circuit board. Has been secured. The invention of claim 2 is characterized in that the transistor is installed at a position close to the outer periphery of the circuit board. The invention of claim 3 is
In a light bulb-shaped fluorescent lamp having a base at one end and a bendable fluorescent lamp at the other end, a high-frequency lighting circuit component mounted on a circuit board is housed in a cover.
The high-frequency lighting circuit component mounted on the circuit board includes a plate-shaped transistor, the transistor is arranged close to the side wall of the cover, and a wide surface of the transistor faces the side wall of the cover. And

[0010]

According to the first aspect of the present invention, since the plate-shaped transistor is laid out along the circuit board, the transistor does not interfere with the wiring and a gap is secured between the transistor and the circuit board. As a result, the heat conduction from the transistor to the circuit board is reduced, the circuit board is prevented from being damaged by the heat of the transistor, and the temperature rise of the transistor itself is prevented because the transistor radiates heat on the entire circumference. You can

According to the second aspect of the invention, when the plate-shaped transistor is installed at a position near the outer periphery of the circuit board, it is easy to disturb the wiring. In such a case, the field-effect transistor is laid down and installed. If you do so, it will not be an obstacle to the wiring.
Further, since this position is close to the cover, the heat radiated from the transistor is likely to be radiated outside through the cover.

According to the third aspect of the present invention, since the plate-shaped transistor is arranged close to the side wall of the cover and the wide surface of the transistor is faced along the side wall of the cover, it is emitted from the transistor. Heat is likely to be effectively dissipated out through the cover.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in FIGS. In FIG. 1, reference numeral 1 is a cover made of synthetic resin, and a cylindrical portion 2 is integrally formed at one end of the cover 1. This cylindrical portion 2 has E2
A screw type base 3 such as a 6-type is attached, and the base 3 is fixed to the cylindrical portion 2 by means such as an adhesive or caulking.

The other end of the cover 1 is closed by a partition board 10. The partition board 10 is made of a heat-resistant synthetic resin such as polyethylene terephthalate and has a substantially circular dish shape. As shown in FIG. 3, the partition board 10 has a flange portion 12 formed at the upper end opening edge of a side wall 11 having a rising shape, and the flange portion 12 is formed with notches 13 spaced apart from each other in the circumferential direction. I am doing it. On the other hand, on the inner surface of the cover 1, a plurality of locking projections 7 ... (Shown in FIG. 1) are formed along the circumferential direction, and the partition board 1
The cutouts 13 of 0 are inserted into the locking projections 7 of the cover 1, and after this insertion, the partitioning board 10 is rotated by a slight angle to support the flange 12 by being caught by the locking projections 7. The partition board 10 is thereby mechanically locked to the cover 1.

Lamp partitioning cylinders 15 and 15 are integrally formed on the partition board 10. A fluorescent lamp 20 is mounted on the lamp mounting cylinder portions 15, 15.

The fluorescent lamp 20 may be U-shaped, W-shaped or the like, but a saddle-shaped fluorescent lamp is used in this embodiment. This saddle-type fluorescent lamp 20 has sealing portions 21 and 21 formed at both ends of a bulb.
21 has a U-shaped bent central bent portion 22 between
The central bent portion 22 is formed by bending so as to face the same direction as the sealing portions 21, 21. The sealing part 2
Electrodes (not shown) are sealed at 1 and 21, and a phosphor coating is formed on the inner surface of the bulb. Then, thin tubes 23, 23 are projected in the sealing parts 21, 21, and an amalgam 24 (shown in FIG. 1) is accommodated in at least one of the thin tubes 23, 23, and the amalgam 24 lights up. It is designed to control the mercury vapor pressure. The valve is filled with a rare gas such as argon.

In such a bent fluorescent lamp 20, the sealing portions 21, 21 formed at both ends are inserted into the lamp mounting cylinder portions 15, 15 formed in the partition board 10, and the sealing portions 21, 21 are formed. 21 and the tube portions 15, 15 are joined by an adhesive 31 such as a heat conductive silicone-based material filled in the lamp attachment tube portions 15, 15. Thereby, the lamp 20 is fixed to the partition board 10.

In this case, as shown in FIG. 4, a plurality of rib-shaped projections 16 ... Are formed on the inner surface of one of the lamp mounting cylinders 15, 15 so as to be circumferentially spaced from each other. There is. These projections 16 ...
Is formed to be slightly smaller than the outer diameter of the sealing portion 21 of the lamp 20, so that when the sealing portion 21 of the lamp 20 is pushed into the tubular portion 15, the sealing portion 21 crushes the protrusions 16 ... The sealing portion 21 is engaged with the tubular portion 15 by these frictions. This is used as a temporary fixing before the sealing portion 21 is joined to the lamp and the mounting cylinder portion 5 with the adhesive 31. The other lamp mounting tube portion 15 is provided at both end sealing portions 21, 2 of the fluorescent lamp 20.
In order to absorb the dimensional variation between the cylinders 1,
Is formed in a long hole (elliptical) shape along the direction.

The central bent portion 22 of the lamp 20 is also provided.
Are bonded to the lower surface of the partition board 10 by another adhesive 32. For this reason, the saddle-type fluorescent lamp 20 is fixed to the partition board 10 by a total of three positions including the both-end sealing portions 21 and 21 and the central bent portion 22.

A high-frequency lighting circuit component is attached to the partition board 10. The lighting circuit component is housed in a space surrounded by the partition board 10 and the cover 1, and is mechanically supported by the partition board 10.

As shown in FIG. 5, the high frequency lighting circuit component includes a smoothing circuit 51 connected to the commercial power source 50, a drive circuit 52 including a high frequency oscillation circuit (inverter), a start timer circuit 53 and the like. The smoothing circuit 51 includes a rectifier 511, an electrolytic smoothing capacitor 512, and the like. The inverter drive circuit 52 includes field effect transistors (FETs) 521 and 521 and an oscillation transformer 52.
2 is used as the main component.

Such high frequency lighting circuit parts 511, 5
Although 12, 521, 521, 522 and the like are mounted on the circuit board 40, the electrolytic smoothing capacitor 512 and the plate-shaped field effect transistor according to the present invention ( FET) 521, 52
1 is shown. As shown in FIG. 4, the electrolytic smoothing capacitor 512
Since it is long, it is mounted upright at the center of the circuit board 40, and has a plate-shaped field effect transistor (FET) 52.
1, 521 are arranged diagonally on the periphery of the circuit board 40.

In the plate-shaped field effect transistors (FETs) 521 and 521, the lead wire 41 led out from one end is joined to the circuit board 40.
Field effect transistor (FE
T) 521, 521 are laid so that the wide surfaces thereof face the upper surface of the circuit board 40, and are inclined parallel to the circuit board 40 or at a predetermined angle α. In this case, the circuit board 40 and the field effect transistor (FET) 521
Are arranged so that there is always a gap 42 between them. This gap 42 is a field effect transistor (F
The distance is such that the heat of the ET) 521 is not thermally conducted to the circuit board 40, and it is desirable that the distance is 2 mm or more in order to insulate heat by the air layer and to shield heat by convection.

The bent fluorescent lamp 20 attached to the partition board 10 is covered with a globe 5. The globe 5 is made of transparent or light-diffusing resin or glass, and in this embodiment, is made of frosted glass. The upper end of the globe 5 is open, and the opening is formed to have a slightly smaller diameter to form a straight opening neck 6.

The globe 5 covers the fluorescent lamp 20 and its opening neck 6 is joined to the partitioning board 10 via a heat conductive silicone adhesive 33. That is,
The opening neck 6 of the globe 5 is adapted to fit on the side wall 11 of the partition board 10, and therefore the adhesive 3 is provided between the opening neck 6 of the globe 5 and the side wall 11 of the partition board 10.
The glove 5 is integrally joined to the partitioning board 10 by being joined by 3.

When the globe 5 is fitted into the open end of the cover 1, the lower edge 8 of the cover 1 comes into contact with or approaches the outer peripheral surface of the globe 5, whereby the outer surface of the lower end of the cover 1 is brought into contact. Since the outer surface of the globe 5 is continuous without a large step, the appearance is improved.

In the bulb-type fluorescent lamp having such a structure, since the lamp 20 is lit by the high frequency,
The electrode loss is small and the luminous efficiency is high. The high-frequency lighting circuit component that supplies a high frequency to the lamp 20 has advantages that it is light in weight because it uses an electronic component and generates less heat than a ballast.

Among the high frequency lighting circuit components, a field effect transistor (FE) belonging to a relatively large component.
T) 521, 521 has a lead wire 41 led out from one end thereof joined to the circuit board 40.
Field effect transistor (FE
The T) 521 and 521 are laid so that the wide surfaces thereof face the upper surface of the circuit board 40. Therefore, the field effect transistors (FETs) 521 and 521 do not significantly protrude from the circuit board 40 and do not interfere with the wiring.

In this case, the field effect transistor (FE
T) 521 and 521 are parallel to the circuit board 40 or inclined at a predetermined angle α, and the distance between the circuit board 40 and the field effect transistor (FET) 521 is 2 mm.
Since the above-mentioned gap 42 is secured, even if the field effect transistor (FET) 521 generates heat, this heat is rarely transferred to the circuit board 40, so that the circuit board 40 is heated and is not thermally damaged. Absent. On the contrary, the circuit board 4
0 may be heated by the heat of the lower lamp 20, but if the gap 42 is secured, the heat from the circuit board 40 will not heat the field effect transistor (FET) 521. .

Then, a field effect transistor (FE
Since the entire peripheral surface of (T) 521 is exposed to air, heat is radiated from the entire peripheral surface, and heat is not contained in the transistor itself, so that an abnormal temperature rise is prevented.

A field effect transistor (FET)
The inclination angle α between 521 and the circuit board 40 is preferably about 0 to 2 °. When the inclination angle α exceeds 2 °, the field effect transistor (FET) 521 protrudes from the circuit board 40, which is an obstacle.

Field effect transistor (FET) 521
As a means for radiating the heat to the outside, an embodiment according to another invention as shown in FIGS. 6 and 7 may be used. That is, in the case of another embodiment shown in FIGS. 6 and 7, a pair of plate-shaped field effect transistors 521 and 521 are arranged at symmetrical positions on the circuit board 40, and these plate-shaped field effect transistors 521 and 521 are arranged. Close to the side wall of the cover 1,
Moreover, the wide surfaces of the field effect transistors 521 and 521 are arranged so as to be substantially parallel to the side wall of the cover 1, and as a result, the plate-shaped field effect transistor 521,
The side wall 521 faces the side wall of the cover 1.

In the case of such a structure, the heat emitted from the field effect transistors 521 and 521 is radiated to the cover 1 and is radiated to the outside through the wide surface of the cover 1. Therefore, the heat of the field effect transistor 521 is satisfactorily dissipated, so that the temperature rise of the field effect transistor 521 is prevented and the life characteristics are improved.

In this case, the plate-shaped field effect transistor 521 needs to be arranged close to the cover 1. In this case, the position near the cover 1 means that the transistor 521 is in contact with the cover 1 or the maximum. There is a space of about 2 mm, and it is preferable that there is no other component in this gap. However, at a position far away from the lamp 20 and not affected by the heat of the lamp 20, another part is provided between the transistor 521 and the cover 1. Even if there is a small non-heat generating component, heat may be radiated from the transistor 52 to the cover 1.

Although the field effect transistor 521 has been described in the above embodiment, the present invention is not limited to this.
It may be a normal plate transistor. In the case of the above-described embodiment, the case where the lamp 20 is covered with the globe 5 has been described, but the present invention is not limited to this, and the present invention can be carried out even if the lamp 20 is exposed without using the globe 5. The partition board 10 may not be used.

[0036]

As described above, according to the present invention, since the transistor is laid out along the circuit board,
Since the transistor does not interfere with the wiring and a gap is secured between the transistor and the circuit board, the heat of the transistor is not directly transferred to the circuit board and the circuit board is prevented from being damaged by heat. Since the heat is radiated on the surface, the temperature rise of the transistor itself can be prevented. Therefore, the life of the circuit board and the transistor is extended.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the present invention and showing an entire bulb-type fluorescent lamp.

FIG. 2 is an enlarged cross-sectional view showing a joint portion of the partition board, the bending fluorescent lamp and the globe of the embodiment.

FIG. 3 is an exploded perspective view of the partition board, the bent fluorescent lamp and the globe of the embodiment.

FIG. 4 is a plan view of the partition board and the circuit board of the embodiment.

FIG. 5 is a diagram of a high frequency lighting circuit of the same embodiment.

FIG. 6 is a sectional view of the inside of the cover showing another embodiment of the present invention.

FIG. 7 is a cross-sectional view of the same embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cover 3 ... Clasp 5 ... Globe 10 ... Divider 15 ... Lamp mounting cylinder 20 ... Fluorescent lamp 21 ... Sealing part 40 ... Circuit board 521 ... Field effect transistor (FET) 41 ... Lead wire 42 ... Gap

Claims (3)

[Claims] 1. A light bulb-shaped fluorescent lamp in which a high-frequency lighting circuit component mounted on a circuit board is housed in a cover having a base at one end and a bent fluorescent lamp at the other end. The mounted high-frequency lighting circuit component includes a plate-shaped transistor, the transistor is laid down along the circuit board, and a gap is secured between the transistor and the circuit board. Light lamp. 2. The bulb-type fluorescent lamp according to claim 1, wherein the transistor is installed at a position close to the outer periphery of the circuit board. 3. A bulb-type fluorescent lamp in which a high-frequency lighting circuit component mounted on a circuit board is housed in a cover having a base at one end and a bent fluorescent lamp at the other end, wherein The mounted high frequency lighting circuit component includes a plate-shaped transistor, the transistor is arranged close to the side wall of the cover, and a wide surface of the transistor is faced to the side wall of the cover. Fluorescent lamp.