JPS59940B2 - fluorescent light - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a fluorescent lamp that can be used as a direct replacement for existing incandescent lamps.

More specifically, the invention relates to a fluorescent lamp in which ionization is induced by a transformer housed within the lamp envelope.

Incandescent lamps are the main lighting fixtures for domestic and residential lighting.

Generally, incandescent lamps contain an incandescent filament within a predetermined non-oxidizing atmosphere contained within a drop-shaped envelope, which may be screwed into a permanent fixture or a movable socket, for example an Edison-shaped filament. Attached to the base.

Although incandescent lamps are widely used, they are relatively inefficient, producing only 15 to 1 fluorine per watt of input power, and have a relatively short and unpredictable lifespan.

Fluorescent lamps have a high efficiency of 80 lumens per watt, making them an attractive alternative to incandescent lamps.

However, traditional fluorescent lamps require a long tube-shaped envelope, along with the need for an auxiliary pressure regulator, which has somewhat limited demand in the domestic lighting market.

The development of fluorescent lamps that fit directly into existing sockets and incandescent light fixtures would allow fluorescent lighting to be used more and more in residential applications, thereby saving energy.

In the field of electric lighting technology, there has long been a need for electrical discharge devices that produce visible light for general illumination without the use of electrodes as the endpoints of a gun or arc discharge.

The idea of electrodeless discharge lamps has been around for a long time, but in order to avoid the need for electrodes, these lamps use a ferromagnetic core or an air-core transformer to transfer electricity within a hermetically sealed envelope containing a gas. The idea has always been to combine energy.

Such devices were not practical or commercially viable, since they used iron-core or air-core transformers, and the loss of the core, among other things, made it impossible to achieve a reasonably efficient light emission. I was not able to have one.

In the past, it has been proposed to use electromagnetic induction to excite electrodeless gas-filled discharge lamps in order to transfer electrical energy to the discharge vessel.

When we experimented in this direction, we found that so far, these methods were extremely unfeasible.

With air-core transformers, the inefficiency of the coupling methods required to achieve power inputs that amount to gas discharges results in
Radiation causes power loss, which is undesirable and even dangerous.

Therefore, such devices did not operate with any degree of efficiency for long periods of time.

Another method proposed in the past is to utilize an iron or ferromagnetic core.

However, these cores can only be used at very low frequencies to avoid core failure due to heating by eddy currents in the iron.

When using alternating current, it is extremely difficult to operate a core deformer to transmit this type of energy at frequencies above 5 or 10 KHz.

According to the inventor's experiments and calculation results, when an iron core transformer is operated at 50KHz, the power loss in the core is approximately 80KHz.
It was found that the range was 90%.

Therefore, from the foregoing, it can be seen that air-core and iron-core transformers, from a practical standpoint, do not operate at the high radio frequency levels necessary to efficiently operate the gas-filled discharge lamp of this invention. will be easily understood.

U.S. Patent No. 3,500,118 and U.S. Patent No. 3.52
No. 1,120 describes a fluorescent pair design that utilizes magnetically induced radio frequency electric fields to ionize a radiating gaseous medium.

Removal of the discharge electrode from within the envelope of such a fluorescent pair extends its life and also allows the shape of the fluorescent pair to be compatible with domestic lighting needs.

U.S. Patent No. 3.50, granted on March 10, 1970
No. 0,118 describes an improved electrodeless fluorescent pair with a radio frequency power source.

This design, while very useful, is bulky and
It consists of a large tubular discharge ring, several ferrite cores, and a remotely located power source.
It is unsuitable for use in many industrial and residential applications.

U.S. Patent No. 3.52, granted July 21, 1970
No. 1,120 describes even smaller fluorescent pairs.

However, this fluorescent pair maintains a high frequency magnetic field in the air surrounding the envelope, thus becoming an undesirable source of electromagnetic radiation and interference.

SUMMARY OF THE INVENTION Briefly, the present invention provides a fluorescent pair arranged in a spherical or droplet shape, which is the typical configuration of residential incandescent lamps.

An annular ferrite core (an
nular ferrite core) is excited with a radio frequency magnetic field.

This magnetic field causes an ionizing discharge in the gaseous medium within the envelope.

Radiation from the ionized gas excites conventional fluorescent light emitters on the inner surface of the envelope as well as on the outer surface of the core to generate visible light.

The core is covered with a glass layer to maintain vacuum integrity and
It can be easily coated with a luminescent material.

Conduction means are also provided to remove heat generated within the core from the outer jacket of the fluorescent pair.

While the characteristic features of the invention are set forth in the claims, the invention itself, as well as other objects and advantages, will be best understood from a detailed description of the following drawings.

The principle of operation of electrodeless fluorescent pairs is described in U.S. Pat.
No. 118 and No. 3,521,120.

FIG. 1 is an external view of a fluorescent pair structure incorporating a horizontal or vertically oriented transformer core as will now be described.

A light-transmitting envelope 11 covering the luminescent body contains the ionizable gas as well as an excitation transformer (not shown).

The power source and stabilization circuitry for the solid state device is contained within a metal assembly 12 that is coupled to the housing 11.

A standard Edison-type threaded plug 13 incorporated into the base assembly 12 receives and extracts energy from a conventional incandescent lamp socket.

The finished structure resembles an ordinary incandescent lamp, for example, the diameter of the envelope is 7°6 crn (sometimes referred to as a size A-24 envelope), and is suitable for luminaires designed in this form. Can be compatible.

The preferred arrangement of the internal components of the fluorescent pair is shown in the front sectional view of FIG. 2a.

The generally spherical or droplet shaped evacuable envelope 11 may be a layer of glass and is formed using methods well known in the lighting art.

One part of the jacket forms a base 11a, through which two metal support rods 15 pass.

Support rod 15 is bonded to the glass in any conventional manner to form vacuum seal 16.

A winding 17 of electrically conductive material, which is insulated for example with a glass fiber fabric, is connected between the metal support rods 15 and interlinks with the toroidal ferrite transformer core 18 .

Core 18 is thus supported within jacket 11.

In this embodiment, the ends 17a of the windings are oriented such that the axis of the core 18 is perpendicular to the support rod 15.

The unique shape of the winding is determined by the operating input voltage of the fluorescent lamp.

Typically, the winding is 1 volt to the core per 5 volts of input voltage.
chosen to have a turn.

An ionizable gas 19 is contained in the space within the envelope.

This gas may be the same as that used in conventional fluorescent lamps and may consist of a mixture of a noble gas, such as krypton, and mercury vapor.

The inner surface of the glass jacket 11, as well as the outer surface of the transformer core 18, is coated with a suitable phosphor 20 that converts ultraviolet light into visible fluorescence, such as calcium halo abatate.

These luminescent materials are well known and, when stimulated by absorbing the ultraviolet light emitted by ionized mercury vapor, which generally peaks at about Gives off a nice light.

In this embodiment of the invention, the ionized gas does not rely on itself to emit light, but rather generates radiation for emitting light from the fluorescent light emitter.

This allows the power input to the gas to be ionized to be relatively small, since the gas itself is not relied on to emit the required light, but instead is used for the radiation that stimulates the illuminant. .

A radio frequency power source 21 mounted outside the fluorescent lamp envelope, preferably inside the base assembly, connects the support rod 15.
A current is passed through the primary winding 17 of the transformer and the core 18 is energized by the magnetic field.

The core ionizes the gas 19 and passes a current to approximately 2537
Stimulates human ultraviolet radiation.

As is typical in common discharge lamps, the ionized gas becomes a negative impedance electrical load that can destroy unprotected low impedance power supplies.

The impedance 24 of the ballast connected in series with the power source 21 and the support rod 15 is chosen to have a positive impedance that balances the negative impedance of the gas.

This is to stabilize the operation by applying a positive impedance load to the power source.

Of course, the selection of core material is an important factor in making this fluorescent lamp operable.

Although the prior literature describes similar fluorescent lamps with air cores, iron cores, or other ferromagnetic cores, the losses inherent in the operation of these conventional cores limit the ability of practical fluorescent lamps. I found that making the configuration impossible.

As described in the above-mentioned patent, the ferrite material must be selected to provide high magnetic permeability and low internal heat losses at the operating frequencies.

As is well known, ferrite is a ceramic-like material characterized by ferrimagnetism, and usually exhibits a spinel structure with a cubic crystal lattice, and its general formula is Me-F.
e204, where Me represents a metal atom.

The invention requires that the material and shape of the core used be such that core losses are less than 50% to allow effective coupling of electromagnetic energy to the light source.

Lower core losses result in less core heating, minimizing the risk of failure and maximizing efficiency.

It is preferred to keep core losses below 25% of the total input power.

High magnetic permeability core materials are required to minimize electromagnetic radiation and to adequately couple radio frequency energy to the gas.

Ferrites with a relative permeability of at least 2000 are preferred.

25 IG (over the frequency range from z to IMHz,
Suitable conilites with these properties are available.

Although high frequency operation is desirable from the perspective of minimizing ferrite losses, radio frequency power sources 2
Due to the cost of currently available semiconductors, the highest frequency at which a practical fluorescent lamp can be operated is approximately 50KH.
limited to z.

Although other materials are available, ferrite type 8100 manufactured by Indiana General Corporation of Keasby, New Jersey, is a 50KH ferrite.
For operation in z, with a peak flux density of 1000 gauss, the loss was 30 mw/cril, which was found to be suitable for use in this fluorescent lamp.

For example, in a typical 40 watt fluorescent lamp, the transformer core 18 has a thickness of 1.3 cm, an inner diameter of 3 CrIL, and an outer diameter of 5 crrL.

The magnetic flux density within the core is approximately 1000 Gauss.

Although it is possible to use a bare ferrite core within the vacuum envelope, it has been found desirable to apply an impermeable glass layer 25 to the core 18 as a glaze before coating it with the phosphor 20. Ta.

The glass layer minimizes outgassing of the ferritic ceramic and allows conventional heating (slow cooling) methods to be used in applying the phosphor coating 20.

In operation, the ionized gas forms a plasma that interlinks with the core of the transformer.

The shape of this plasma can be adjusted by varying the gas pressure within the fluorescent pair over a range of about 0.2 to about 2.0 Torr.

It has been found that a gas pressure of approximately 1 torr provides a gas plasma that uniformly illuminates the fluorescent lamp.

Typical plasma 22 shapes are shown in FIGS. 2b and 2c.
2d and 2e, the cross section of which is shown in FIG.

(In these drawings, the transformer core 18 is shown for clarity.
Although the ferrite materials mentioned above improve efficiency,
Watt's fluorescent lamps must dissipate more than 10 watts of heat from the transformer core.

Heat dissipation is an important issue because the fluorescent lamp core operates in a substantial vacuum.

For example, ferrite materials suitable for use in the present invention have a cue point of 150°C or less, and it is known that at temperatures above 120°C, the efficiency of the light emitter decreases.

These temperatures therefore require a fluorescent lamp design that allows the lamp to operate below these temperatures.

3a and 3b show a core heat dissipation structure suitable for the fluorescent lamp of the embodiment shown in FIG. 2. FIG.

A metal strip 29 is coupled to the outer periphery of the ferrite core 18 and welded to the support rod 15.

A glass layer 25 is provided on the core 18 and the metal strip 29.
is provided to provide thermal contact and serve as a base for the light emitting body 20.

The heat generated in the core 18 is transferred from the support rod 15 to the base 1 of the outer cover.
13 and is conducted to the outside and dissipated.

The electrical connection to the primary winding 17 of the transformer is made by connecting two rods 1
5a, as shown in FIG.

A 40W fluorescent lamp made in this way has an efficiency of 1 fluorine per watt of input power, compared to a conventional incandescent lamp, which has an efficiency of only 15 to 1 fluorene per watt of input power, as mentioned above.
It has an efficiency of 80 lumens per watt.

An embodiment of a fluorescent lamp with good heat dissipation and uniform fluorescent illumination is shown in FIG.

In this fluorescent lamp, a glass outer cover 11 with a base 11a is
It is made similarly to the embodiment of FIG. 2a.

Two support rods 15 as well as an electrical contact rod 15a pass through the base and have a vacuum seal 16.

One side 1 of the annular ferrite core 18 is coupled to a metal heat dissipation ring 23, and this ring is welded to and supported by the support rod 15.

A primary winding 17 is wound around the core and connected between the electrical contact rod 15a and one of the support rods 15 at 15b.

Similar to the embodiment of FIG.
a to a stabilizing impedance 24 and to a radio frequency power source 21 for energizing the core 18 .

The heat generated within the core is thus efficiently transferred to the ring 23.
and is conducted to the support rod 15 through which it is conducted from the vacuum envelope 11.

Figure 5 shows details of the core structure used in fluorescent lamps.

A metal ring 23 is bonded to one side of the ferrite core 18.

This ring 23 may be made of copper, aluminum, beryllium or any other material that has a higher thermal conductivity than ferrite.

A support rod 15 is welded to the ring 23 and provides a heat transfer path (not shown) from the core to the outside of the vacuum envelope.

A glass layer 25 is applied over the core 18 as well as the metal ring 23 to provide a good thermal bond, minimize outgassing, and provide a substrate for the emitter 20.

In another embodiment of the invention, an instant-activation fluorescent lamp is provided.

As is well known, relatively low voltages are sufficient to keep the gas arc operational once the arc is established, but higher voltages are generally required to cause initial breakdown. It is.

In addition to causing an initial dielectric breakdown that facilitates the ionization of mercury, which is a common metal vapor for carrying the discharge used in gas-filled steam discharge lamps, this may also be caused by the presence of inert gases that easily ionize, such as argon. , that's right.

This high starting voltage is often provided by a mechanical starting device with capacitive or inductive elements, which suddenly applies a high voltage surge to the device's electrodes, causing initial ionization. .

Alternatively, a stabilizing transformer is used to generate the required voltage.

In this invention, an auxiliary secondary winding with a sufficient number of turns to act as a step-up secondary is provided on the ferrite core to extract a very high voltage and apply it to the fluorescent lamp. This problem was quickly solved cheaply and easily by the discovery that it was possible to induce high starting voltages that rapidly caused the initial breakdown necessary to operate the fluorescent lamp of the present invention. It turns out that it can be solved.

FIG. 4 illustrates one method of initiating ionization of gas 19.

A high voltage secondary winding 27 is applied to the core 18 and covered with a layer of glass.

When first energized, the magnetic field in the core induces a high voltage across the winding ends 27a, forming a glow discharge therebetween, thus initially ionizing the gas 19.

The fluorescent lamp plasma 28 is hollow toroid-shaped and surrounds the fluorescent lamp core structure.

FIG. 6 schematically depicts an electrical circuit useful in the operation of a fluorescent lamp.

A radio frequency power source 21 receives line voltage and frequency power from an Edison type threaded plug 30;
It provides an output of approximately 50 volts at 50 KHz for exciting the transformer core 18 through the primary winding 17.

The ends 27a of the windings are energized by the high voltage secondary winding 27 to create a spark discharge within the fluorescent pair.

The plasma 22 thus formed within the fluorescent pair becomes a one-turn secondary winding, which extracts power through the transformer core 18.

A ballast impedance 24 connected in series with the radio frequency power source 21 and the primary winding 17 limits the plasma current and ensures stable operation.

The radio frequency power source may be of any known type.

For example, the inverter circuit described in US Pat. No. 3,521,120 is suitable for use in fluorescent lamps operating within the power range.

From the above description, those skilled in the art will appreciate that the present invention provides a fluorescent lamp that is physically and electrically compatible with existing residential incandescent lamps.

This fluorescent lamp can be used in existing incandescent lamp sockets, and its light output is 30% higher than that of comparable existing devices.
It will double.

This fluorescent lamp does not have electrodes within the vacuum envelope, thereby eliminating one of the major causes of failure in conventional fluorescent lamps.

The high frequency magnetic fields associated with inducing gas ionization are confined to the closed paths of the ferrite, resulting in
Electromagnetic interference is minimized.

Fluorescent lamps constructed in accordance with preferred embodiments of the present invention are highly useful in that they eliminate electrodes, which are the source of many of the limitations of today's fluorescent lamps.

Therefore, for example, burnout of the electrodes will never cause failure of the fluorescent lamp of the present invention.

Similarly, sputtering of the electrode material onto the inner surface of the lamp wall, leading to its darkening, is completely eliminated.

Although preferred embodiments of the invention have been described in detail, various modifications may be made by those skilled in the art.

It is, therefore, to be understood that the appended claims are intended to cover all such modifications that come within the scope of this invention.

This invention may take the following embodiments in relation to the claims.

The means for energizing the core includes a plurality of substantially parallel metal support rods penetrating through the cap part of the outer jacket, interlinked with the core and connected to the support rods, and supplying radio frequency energy to the core. consisting of a winding having a plurality of turns and means for supplying radio frequency energy.

(a) In item (a) above, the means for supplying radio frequency energy is constituted by a power source adapted to convert input energy into radio frequency output energy.

In paragraph (9) above, the power source is mounted within a cylindrical member, the member having a first end and an opposite end, the first end being outside the base portion of the jacket. A fluorescent lamp base plug coupled and adapted to be inserted into a lamp socket to receive input energy is attached to the opposite end of the cylindrical member, and a power source is connected to the fluorescent lamp socket. connected to the base plug to receive input energy therefrom, and a power source connected to the support rod for transmitting radio frequency output energy.

2) In item 1) above, the power source applies radio frequency output energy at a voltage equal to the number of turns making up the first winding multiplied by approximately 5 volts.

e) In the above item), the radio frequency energy is approximately 25
between KHz and about IMHz, preferably 50 IG (z
to have a frequency of

f) In the above item A), the core is coated with a glass-like material that is impermeable to gas, and is adapted to receive the light emitting body.

g) In the above item f), the core is coupled to a metal heat transfer member, and the heat transfer member is within the glass-like member.

h) In the above item g), the metal heat transfer member is selected from the group of metals consisting of copper, beryllium, and aluminum.

h) In the above item g), the ferrite core is ring-shaped,
The heat transfer member is coupled to the outer periphery of the core and to one or more metal support rods, or to a flat ring coupled to a flat surface of the core and to one or more metal support rods.

n) In the above item, there is provided at least one pair of metal starting electrodes disposed within the envelope and encapsulated in glass, and means for forming a glow discharge between the starting electrodes.

h) In the above item h), the means for forming a glow discharge is
It is a glass-coated winding provided on a ferrite core, and both ends of the winding constitute starting electrodes.

e) The pressure of the ionizable medium is approximately 0.2 Torr and approximately 2.0 Torr.
torr, preferably 1 torr.

W) In the above item A), the ferrite core is annular, and the axis of the ferrite core is approximately parallel or perpendicular to the metal support rod.

This invention may take the following embodiments in relation to the claims.

force) flat metal rings and cores coated with glass material.

y) In the above item (force), the glass material is impermeable to gas.

(b) A second winding is wound around the core, and both ends of the second winding maintain a glow discharge, thereby ionizing the medium.

(b) In item (d) above, the second winding is covered with glass.

In the preceding paragraph, the means for inducing a radio frequency voltage comprises a radio frequency power source external to the envelope, and the radio frequency power source is connected to one metal support rod and one connection. A radio frequency voltage must be supplied between the parts and the parts.

B) In the preceding paragraph, there is provided a generally cylindrical base element surrounding the radio frequency power source, the base element having a first end and another end, the first end of the cylindrical base element an end coupled to a flat, circular base portion, and the other end of the cylindrical base element receiving electrical energy from a power line source;
adapted to transmit the electrical energy to a radio frequency power source.

f) In accordance with item (d) above, the other end of the cap element is adapted to be inserted into a power line source in the form of a light socket, from which it receives electrical energy.

n) In the above item (i), the ionizable medium is composed of a mixture of rare gas and mercury vapor.

c) In item (a) above, the rare gas is krypton.

This invention may take the following embodiments in relation to the claims.

m) The means for energizing the core is composed of a winding interlinked with the core and means for generating a radio frequency current in the winding.

This invention may take the following embodiments in relation to the claims.

(1) The means for generating an electric current consists of a plurality of electrically insulated metal elements that penetrate the outer jacket, and one end of the winding is
The other end of the winding connected to one element is connected to another element and a radio frequency voltage source external to the jacket is connected between said one metal element and said another metal element. To connect.

i) The core is covered with a material that is impermeable to gas.

The ionizable medium has a pressure between about 0.2 Torr and about 2.0 Torr.

[Brief explanation of drawings]

Figure 1 is a perspective view of the completed fluorescent lamp, Figure 2a is a front view of an embodiment of the fluorescent lamp with the axis of the transformer perpendicular to the base conductor, and Figure 2b is the fluorescent lamp of Figure 2a. FIG. 2C is a side view of the plasma in FIG. 2B; FIGS.
3a and 3b are cross-sectional views of a transformer core assembly using circumferential heat transfer strips; 5 is a cross-sectional view of an embodiment of the transformer core with axial heat transfer rings; FIG. 6 is a circuit diagram of the operating circuit of the fluorescent pair of the present invention; FIG. It is a diagram. 11: Outer cover, 18: Core, 19: Ionizable gas (medium), 20: Luminous body.

Claims (1)

[Claims] 1 comprising an optically transparent outer jacket and a ferrite-based core having a winding for energizing the core with a radio frequency magnetic field; an ionizable medium, the medium sustaining the discharge of the electric field induced by the core and emits radiation, and a light emitter on the inner surface of the envelope, the light emitter being The device converts radiation into visible light, and the outer sheath 11 has a substantially spherical shape, and the core 1
A fluorescent lamp characterized in that 8 has a closed loop contained within said envelope.