JPS585506B2 - Electrodeless discharge device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates generally to high frequency electrodeless lamps, and more particularly to high frequency electrodeless lamps specifically designed to have a relatively constant predetermined operating frequency with minimal output harmonics of the operating frequency. It is something.

High frequency electrodeless (HFE) lamps have received considerable attention in recent years as a potential replacement for standard household incandescent light bulbs, which have relatively low efficiency in converting electricity to light.

Fluorescent lamps are efficient at converting electricity into light, but their large size and the need for ballasts limit their use to domestic use.

Compared to standard fluorescent lamps, high-frequency electrodeless lamps can be manufactured relatively small.

Anderson, April 12, 1977
U.S. Pat. No. 4,017,764, issued to Son, discloses a fluorescent high frequency electrodeless lamp in which a ferrite core is completely contained within a phosphor-coated envelope or enclosure.

Column 5, lines 38-43 of this US patent suggests mixing polyimide resin with powdered ferrite to reduce the magnetic permeability of the core.

Hollister dated May 1, 1977
No. 4,010,400 discloses a high frequency electrodeless lamp that uses a ferrite core as part of the tuned circuit output of a radio frequency energizing source.

Ander dated October 19, 1976.
U.S. Pat. No. 3,987,335, issued to Son, discloses a fluorescent high frequency electrodeless lamp in which a ferrite core is only partially contained within a phosphor coated enclosure.

Fri-eb dated September 30, 1975
U.S. Pat. No. 3,908,264 to erg et al. discloses a high permeability core forming part of a tuned circuit,
In this case, the resonant frequency of the tuned circuit is calibrated by removing part of its core.

Kalb-f dated September 22, 1964
U.S. Pat. No. 3,150,340 to Ell) discloses a high Q coil annular core that includes an air gap to obtain a high Q value for the coil.

An early design for an electrodeless discharge lamp in which the discharge was maintained by a magnetic field created by a magnetic coil was published in U.S. Pat. No. 1,8 by Morrison, July 7, 1931.
No. 13,580.

In accordance with the present invention, an electrodeless discharge device is provided that is designed to operate at rated power consumption when energized with predetermined radio frequency energy, such as generated by a radio frequency power source.

The power supply has at its output a tuned circuit having a resonant frequency close to the predetermined radio frequency at which the discharge device operates.

This discharge device includes a sealed, light-transmitting spherical enclosure of predetermined dimensions, and contains a discharge sustaining medium having a phosphor layer on the surface of the enclosure.

A magnetic core, such as a ferrite, is positioned to transfer energy to the atmosphere within the enclosure, and the ferrite material that primarily constitutes the core has a very high magnetic permeability.

The core has a generally annular profile and, according to the invention, the base core is cut to include narrow gap means of low magnetic permeability material across its cross section.

A predetermined number of windings are wound around the core, and the windings are connected to a radio frequency power source by an introduction member.

This core forms part of the tuned circuit output of the radio frequency power supply, and the magnetic permeability of this core constitutes the main variable by which the resonant frequency of the tuned circuit output can be varied.

During operation of this discharge device, the gap means in the core stabilizes the effective magnetic permeability of the core, so that even if the magnetic permeability of the main material composing the core changes greatly, the total effective magnetic permeability of the gapped core remains only a little. or does not change.

This stabilizes the operating resonant frequency of the tuned circuit output, and the gap means in the core also substantially increases the Q of the tuned circuit compared to the Q of other similar tuned circuits not using gaps. , substantially increasing the selectivity of the tuned circuit output, and substantially suppressing output harmonics at the resonant frequency.

For a better understanding of the invention, reference will now be made to preferred embodiments thereof that are illustrated in the accompanying drawings.

In FIG. 1, an electric lamp 10 is generally constructed of a sealed light transmissive tube of predetermined dimensions surrounding a discharge sustaining medium such as several torr of argon and a small amount of mercury 14, similar to a conventional fluorescent lamp. It is composed of a spherical enclosure 12.

On the inner surface of the envelope 12 is a layer 16 of luminescent phosphor.
is attached.

Contained within the envelope is a core 18 which is mainly made of a magnetic material with high magnetic permeability and has a loop (annular) shape with predetermined dimensions.

As a particular example, the core has an annular shape and, in accordance with the present invention, includes a narrow gap 20 of low magnetic permeability material, such as mica, across the cross-section of the core.

A winding 22 having a predetermined number of turns is wound around the core 18, and an introduction member 24 connects this winding 22 to a radio frequency power source 25, and the radio frequency power source 25 is a standard 115V (AC ), a high frequency driver (
(exciter) It is equipped with an oscillator section 26.

The operation of the electric light 10 as shown in FIG. 1 will be explained as follows.
When the lamp 10 is energized, a radio frequency electromagnetic field passes through the core and the radio frequency electromagnetic field generated around it excites a discharge sustaining medium within the envelope to emit short wavelength radiation. Furthermore, the phosphor layer is excited to emit visible light that passes through the envelope.

Electrically, the ferrite core has a winding 22 with N turns on the primary side, and an isoelectric lamp resistance RL on the secondary side.
It can be thought of as a transformer that performs one-turn discharge with the load being .

FIG. 2A shows an equinodal circuit for the electric lamp 10 in which the lamp voltage VL is indicated.

FIG. 2B shows a further simplified version of this isochoric circuit.

During operation, the lamp load is approximately N2 within the coil 22.
It is expressed as RLΩ.

4 and 6 show two examples of many possible circuit configurations suitable for driving high frequency electrodeless lamps.

These circuits perform self-oscillating class A, class B, or class C operation, and class B or class C operation is preferred because the maximum efficiency matches the output power.

The operating frequency of these circuits is determined by the values of the inductance L and capacitance C of the tank circuit.

For a given lamp-core gas configuration and arrangement, the operating voltage VL of this lamp is fixed within fairly narrow limits.

Under class B or class C operation, the effective voltage VC of the primary winding of a special lamp, as described below, is approximately 0.707 VDO.
Or, in this case, 113V (effective value).

The number of turns of the primary winding 22 on the ferrite core is N=VC/
VL=0.707VDC/VL.

Next, the influence of changes in magnetic permeability of the core will be explained.

The magnetic permeability of the core may change due to temperature fluctuations in the lamp during operation or manufacturing errors during the manufacture of the ferrite core.

In an equinodal circuit as shown in FIG. 2B, the resonant frequency f0 of this circuit is given by the following equation.

Here, L is the inductance (H) of the coil 22, and C is the tank capacity (F).

L can be obtained as follows.

Here, N is the number of turns, μm is the effective magnetic permeability, Ac is the cross-sectional area of the core (cm2), and lC is the magnetic path length in the core (
cm).

To determine the effect of changes in the magnetic permeability of the main material that makes up the core, the magnetic permeability of a completely closed-loop ferrite core is expressed as μC.
It is defined as

If a narrow gap is provided in the core 18 with a low permeability μA material such as mica across the cross-section of the core, the effective permeability of the core changes to μm.

In this case, the magnetic permeability μC and μm have the following relationship.

Considering a practical case, an outer diameter of 6.096 cm, 3.
For a commercially available ferrite core having an annular shape with an inner diameter of 556 cm and a thickness of 1.27 cm, the value indicating the magnetic permeability μC of the ferrite is 5,000, and the effective diameter cross-sectional area AC is 157 d; And the average magnetic path length lc is
It is 14.43cm.

When μA=1 and a mica gap with a thickness of 0.015 cm is provided in the core, the effective magnetic permeability of the core 18 can be calculated from 5,000 to 80 by substituting the above values into equation
It can be seen that this decreases to 6.8.

Consider the effect on the effective magnetic permeability of the gapped core when the actual magnetic permeability of the main material making up the core, ie, ferrite, changes or decreases by 20%.

If the actual permeability of ferrite is 20%, i.e. 5,00
If it decreases from 0 to 4,000, this correction value can be expressed as
By substituting , the effective permeability of the gapped core is 77
It can be seen that the value is 5.5.

From this, the actual magnetic permeability of ferrite material is 20%.
Even if it changes, the change in μm (ie, the effective magnetic permeability of the core) is only 3.9%.

Thus, by providing a narrow gap in the core, changes in the permeability of the ferrite material due to manufacturing tolerances and/or temperature have little effect on the actual or effective permeability of the gapped core. do not have.

Next, we will discuss the effect on the resonant frequency of the tuned circuit due to the stabilized magnetic permeability of the core.

As mentioned above, the core constitutes part of the tuned circuit output of the radio frequency power supply, and its resonant frequency is determined according to the equation described above.

For a core with 22 turns of winding and an effective permeability of 806.8, the core inductance would be 534 microhenries (μH).

Typical values of capacitance used with this tuned circuit are 5,
000 picofurad (pF), which is 97.4
Generates a resonant frequency of the tuned circuit of KHz (see formula ■)
.

In practical cases this is a highly desirable operating frequency in order to limit electrical losses in the core to negligible amounts and to provide good discharge.

Using the previous example where the effective permeability of the gapped core was reduced to 775.5, the resonant frequency would be increased by 1.99%.

However, if the gap is not included in the core, a 20% decrease in core permeability will increase the resonant frequency of the tuned circuit by more than 10%.

From the above, it can be seen that providing a gap within the core stabilizes the resonant frequency of a tuned circuit that includes the core as a part, and is very desirable in actually designing electric lamps.

It should be noted that the predetermined frequencies at which electric lamps are suitable to operate vary considerably within the low frequency radio frequency range, but in practice, from a point of view of minimizing core losses and radiation levels, the predetermined frequencies range from 70 to 1.
An operating frequency of around 10 KHz is very satisfactory.

Next, we will discuss the effect of the gapped core on suppressing output harmonics at the resonant frequency.

The inductance LC of the core and coil without a gap is determined by the above equation (2).

To repeat, here the number of turns is 22 and μC=5,0
00, AC=1.57, and 1C=14.43, LC=3309 μH.

If, as mentioned above, an air gap is provided and the effective magnetic permeability of the gap core is 806.8, then the inductance LA of the gap core and the coil can be calculated as 5 using equation (2).
It becomes 34μH.

In an equal circuit as shown in FIG. 2B, the effective Q of the tuned circuit is given by:

For a 40W electric lamp, the value of VL is typically 5■ and RL is 0.625Ω.

Substituting the value of LC=3309μH1LA=534μH into equation (■), the Q of the circuit without air gap is 0.149,
The Q of a circuit with air gaps is approximately 0.93.

For low values of Q, the selectivity of the tuned circuit to harmonics becomes very poor, whereas if Q is close to a value of approximately 1, the selectivity is as shown in Table A below. This is a huge improvement.

The efficiency of the output circuit is Q, which is the Q of the circuit with the load removed.
It can be defined as follows by U and QL, which is the Q of the loaded circuit.

In reality, QU is approximately 20 and the following Table B can be obtained.

As seen from Table B, the value of QL is approximately 1.

There is a loss in efficiency of about a factor of 5, but selectivity is greatly improved for coils with much lower QL.

Since it is highly desirable to minimize harmonics while keeping efficiency relatively high, it is desirable to obtain a tuned circuit quality factor of about 1.

Here, an actual example will be described.

In FIG. 3, a lamp 10 includes a sealed, light-transmissive spherical or pear-shaped envelope 12 of predetermined dimensions.

As an example, the enclosure 12 has a height of 6 inches and an outer diameter of 4 inches.

The envelope 12 is evacuated through a tip 30 on its top;
and a discharge sustaining charge consisting of 1.5 torr of argon and a small amount of mercury-14.

A phosphor layer 16 is applied on the inner surface of the envelope and can be, for example, any standard halogenated phosphate.

Alternatively, a three-component mixture of rare earth active phosphors can be used to improve temperature characteristics.

Such phosphor mixtures are known from Verstegen (Verst).
U.S. Patent No. 3, dated February 10, 1976,
No. 937,998.

As previously discussed, the core 18 is operably located within the enclosure 12, and the core 18 is comprised primarily of a high permeability magnetic material having an annular shape of predetermined dimensions and cross-sectional area, as previously discussed. ing.

The core 18 preferably has an annular shape for manufacturing convenience, but this shape can vary.

As previously mentioned, the core also includes a narrow gap 20 across the cross-section of the core and a 20-turn winding 22.
is wound around the core 18.

Although the preferred primary material making up core 18 is ferrite, other magnetic materials may be substituted.

As is well known, ferrite, according to the dictionary definition, is usually formed by treating hydrated ferric oxide with an alkali or by treating ferric oxide with a metal oxide. It consists of a compound, in some cases considered a spinel, such as NaFeO2 or ZnFe2O4.

The ferrite core mentioned above is manufactured in New Chassis, USA.
Keasby's Indiana General A Division of Electronic Memories and Magnetics Corporation (Indiana G.
eneral, a Division of Elect
ronicMemories & Magnetics
Corp.

8000 series by Keasbey, NJ) and without gaps as described above.

Such ferrites are usually produced using sintering techniques.

When sintered into an annular configuration, ferrite has a high magnetic permeability (
(e.g. 5000) and low electrical resistivity (e.g. 100Ω・
cm).

The introduction member 24 is constituted by a combination of an exciter 26 and a power supply 28 (shown in block configuration in FIG.
The winding 22 is connected to a high frequency power source 25 located inside the winding 2.

As mentioned above, the core 18 constitutes a part of the tuned circuit output section for a high frequency power supply, and the magnetic permeability of this core is the main constant that can change the resonant frequency of the tuned circuit output section. be.

Other details of the lamp 10 are of generally conventional construction, and the three leads to the coil 22 are enclosed via a stem 34 to connect the power supply 2 within the elongated stem and neck 32.
5, and the power supply 25 is further connected to the ordinary screw cap 3.
6 and the base 36 is attached to the neck portion by a base adapter member formed of a suitable plastic such as phenolic resin.

Above the core 18 is a 25
It is preferable to apply a phosphor to make the most efficient use of the 4 Ωm radiation.

Operation of the lamp 10 is initiated by an additional winding 40 consisting of a relatively large number of turns fixed on the core 18 and terminating in the envelope 12 at ends 42 a predetermined distance apart. are doing.

In operation of this device, when the tuned circuit is first energized, the additional winding 40 develops a relatively high voltage across the spaced ends 42 and the capacitive coupling therebetween causes the additional winding 40 to
The discharge sustaining medium within 2 is ionized to begin operation of the device.

Once activated, winding 40 is effectively disconnected from the circuit.

As an example, winding 40 is comprised of 88 turns, and ends 42 are separated by 1 cm or more (eg, 2 cm).

A circuit used to energize a lamp such as that shown in FIG. 3 is shown in FIG.

This circuit is composed of an AC-DC conversion power supply section 28 consisting of a diode full-wave rectifier 44 and a filter capacitor 46, and a high frequency exciter/oscillator section 26, and the high frequency exciter/oscillator section 26 is a core section. 18, a tuned circuit capacitor 48, and a single or double capacitor fixed on the core 18.
It is composed of a feedback coil 50 with a turn.

Although the additional starting winding 40 is shown connected to one of the lead-in wires, this need not be the case.

Three connection terminals 52 on stem 34 are shown.

To operate this circuit, transistor 54, capacitor 55, and blocking diode 56 provide the necessary oscillation.

Capacitor 55 and resistor 57 provide the appropriate bias for transistor 54.

In the circuit shown in FIG. 4, a 160V DC voltage is generated by a full wave rectifier 44.

A turns ratio of 22:1 results in an AC voltage drop of 5V across the discharge, and with a load resistance of 0.625Ω, the lamp operates with a power consumption of 40W during discharge.

Using this type of lamp and using a cool-white halogenated phosphate phosphor, an efficiency of 601 m/W was typically obtained, with an additional power loss of 17 W.

Significantly higher efficiency can be expected by using rare earth activated phosphors.

Another lamp embodiment 10a is shown in FIG. 5, in which only a portion of the core 18a is housed within the envelope 12a.

A 22-turn winding 22 is wound around the portion of the core 18a located outside the hermetic enclosure 12a.

However, the 88-turn starting winding 40 initiates the discharge with the end 42 located within the envelope.

In this embodiment, four lead-in wires 24a connect the radio frequency power source 25, the main winding 22, and the feedback coil 50.

The circuit for energizing the lamp of FIG. 5 is shown in FIG. 6, showing the connection terminal 58 between the coils 22 and 50 and the power source 25.

The circuit is otherwise the same as that shown in FIG.

In this example, the gap means are each 0.007
Two gaps 20a are formed with a thickness of 5 cm and are located in a portion of the core 18a passing through the enclosure 12a.

FIG. 7 shows yet another embodiment of a lamp 10b, which includes a thermally conductive metal member 60, such as a piece of copper.
Generally corresponds to the embodiment shown in FIG. 3, except that the ferrite core 18 is arranged in a thermally conductive manner around the ferrite core 18.

An additional heat dissipating member 62, such as a heat radiator, is provided on the outside of the lamp cap member 38b.

The copper piece 60 that wraps around the outside of the core is an added copper conductive member 64.
Heat is transmitted to the heat radiating member 62 by this.

In another possible embodiment, a metal enclosure 65 provided for the power source 25 is such that heat is transferred to another heat sink element 66 by means of an additional conductor 68.

In any of the embodiments described above, winding 22 is preferably insulated from the ferrite core, and this
Twier Crampons, Pittsburgh, Pennsylvania 0
This is easily accomplished by providing the core with a layer 70 of a refractory inorganic cement, such as a zirconia-based cement sold under the trademark "Zuier-Eisen Cement" by Auereisen Cement. .

A typical thickness of this layer 70 is 0.05-0.1 mm.

Other materials that may be applied to the ferrite core to insulate it from the windings include “Pyroceram”.
Corning Glass (Corni am)” trademark
There are opaque glasses such as those sold by NG Glass.

Alternatively, winding 22 may be provided with a glass or fiberglass insulation layer around it.

In the preferred embodiment, the gap means is said to be made of mica spacers.

Other materials may be substituted, such as alumina, zirconia, magnesia, strontium oxide disks.

Alternatively, there is no need to insert a filler into the gap, and the lamp atmosphere can be a low permeability material.

Although the gap reduces the effective permeability of the core for the embodiments described above, the effective permeability of the core is approximately 20
It is desirable that it does not decrease below 0.

This is, of course, considerably reduced from the normal magnetic permeability of ferrite itself.

Many different energizing circuits can be used in place of the examples described above.

However, it is highly desirable to use an energizing circuit in which the core forming part of the tuned circuit is provided at the output of the tuned circuit, and in such a case the gap provided according to the invention is useful for stabilizing the operating frequency. This brings about the double benefit of suppressing harmonics.

The embodiment of the lamp as described above can be substantially modified.

For example, the power supply need not be provided within the neck of the enclosure, but may be provided separately, for example by a standard threaded eyepiece that fits into a standard incandescent socket.

The light itself is then plugged into a power source or
Or it can be attached in other ways so that the light or power source can be replaced separately.

Providing a narrow gap of low magnetic permeability in the core provides other advantages for lamp construction.

For example, if the core is physically isolated from the atmosphere within a sealed enclosure, functionally arranged to transfer energy to that atmosphere within the enclosure, and the core is formed as a closed-loop magnetic material. is U.S. Patent No. 4,00
There are manufacturing problems as outlined in US Pat. No. 5,330.

Further, in FIG. 4 of this patent, a glass sleeve is inserted into the already made core, which is further melted onto the glass curved member, and then the core and curved portion are attached and placed within the enclosure. It is enclosed.

According to the invention, when providing the low permeability gap means, the core can first be divided into separate parts and then assembled using cement or adhesive.

Additionally, because the core is insulated from the discharge-sustaining atmosphere within the discharge lamp envelope, for some embodiments the core portion may be bonded using a relatively easy-to-handle adhesive such as a conventional epoxy cement. can be joined.

If such a cement is used with a core exposed to the atmosphere operating within the envelope, the generated ultraviolet light typically degrades the epoxy cement and adversely affects lamp performance through decomposition.

In the various embodiments shown in FIGS. 8-15, the core is physically isolated from the atmosphere within the sealed enclosure and is in an operating position such that energy is transferred to the atmosphere within the enclosure. It is in.

In these embodiments, the core is divided into separate sections and the sections are then assembled, preferably by providing low permeability gap means as part of the joint between the sections of the core. This allows for greater flexibility in the design of electric lights.

In the embodiment shown in FIGS. 8 and 9, the envelope 1
2c has an overall cylindrical shape, and is provided with two hollow elongated glass passages 70 penetrating the envelope 12c in the same direction.
is open.

As before, this seal is coated with phosphor to eliminate the decomposition products of the annealing bonding material, and after the phosphor film 16 is attached, it is dried, evacuated, and a discharge sustaining filler is applied through the suction lower 3. By charging, the sealing body forming process is completed.

Thereafter, core 18c is inserted through elongated passageway 70;
It is provided so as to transmit energy to the atmosphere within the enclosure 12c.

In such embodiments, the core 18c is comprised of at least two sections, one of which is U-shaped and the other section 76 is adapted to be attached near the end of the U-shaped section 74. It has become.

These two core parts are bonded together by a suitable cement, such as a conventional epoxy cement, and a spacer of low permeability material forming the gap means 78 is made of thin mica plate and the two core parts 74 and 76 are bonded together. Glue to join.

In such embodiments, gap 78 may be made of one mica plate or two mica plates may be used.

In other respects, the winding 22c may be substantially as described above, with ignition starting being effected by the winding 40c, which is capacitively coupled through the glass wall of the passageway 70.

In other respects, lamp 10c is similar to the previous embodiment, including a phosphor film 16 and a small amount of discharge sustaining filler, such as mercury 14.

In the figure, only a portion of the phosphor 16 is shown.

A practical example of the electric light 10c is shown in FIG. 9, in which a modified envelope 12c is fixed to a modified hollow base adapter 38c, which includes a power supply circuit 25 and further It is connected to a conventional screw cap 36.

This structure also has other advantages.

This is because the lamp 10c can be designed in such an orientation that the passageway 70 is arranged vertically so that the passageway TO acts as a chimney to cool the core 18e during operation of the lamp 10c.

In order to increase this cooling effect, the hollow base adapter 38c
A hole 80 is provided in the lamp 10c, and a hole 84 is also provided in the light-transmissive material 82 of the lamp 10c to complete the chimney effect.

In order to avoid exposing the epoxy cement portion of gap 78 to ultraviolet radiation generated within envelope 12c when the lamp is in operation, passageway 70 is designed to be substantially ultraviolet ray resistant, such as conventional soda-lime-silica glass. Made of non-emissive glass.

Alternatively, a conventional ultraviolet reflective material may be coated on the interior surface of the enclosure of passageway 70, which coatings are well known.

FIG. 10 and FIG. 11 show an electric light 10d according to another embodiment.
is shown in which the modified enclosure 12d is provided with a hollow elongated curved passageway 86 which is isolated from the discharge sustaining medium within the enclosure and is made of soft or hard glass. It is made of glass such as.

This hollow curved passage 86 passes through the wall of the enclosure 12d, and is coated with phosphor 16 inside the enclosure, annealed, dried, evacuated, and filled with a discharge sustaining filler (mercury).
Core 1 after processing completely by injecting 14
8d is assembled by bonding its three core portions 90, 92 and 94 with a suitable cement such as epoxy, and at least one of the joints 96 includes a suitable low permeability spacer.

In the figure, only a portion of the phosphor film 16 is shown.

The starting coil 40d in this embodiment is wound around the outer portion of the passage 86, which is a curved tubular member, so that after the core 18d is installed, it is magnetically coupled to the core 18d and facilitates starting the lamp 10d. I'm letting you do it.

The discharge device 10d shown in FIG. 11 corresponds to a practical example, in which the enclosure 12d is fitted into a hollow base adapter means 38d.
d has a built-in power supply circuit 25, and as mentioned above, the winding 2
2d and the cap 36.

In the previously described embodiment shown in FIGS. 8-11, the envelope can be manufactured without exposing the core of the lamp to the high temperatures necessary for the envelope manufacturing process.

In Figures 8-11, the enclosures 12c and 12d are made of a light-transmissive material such as glass, and are evacuated and sealed.

Inside the enclosure are hollow conduit passage means (70 and 1 in FIG. 8).
86 in FIG. 0), and the ends of the passage means (72 in FIG. 8 and 88 in FIG. 10) seal with and pass through a different portion of the wall of each enclosure.

Each end of the passageway is apertured to allow insertion of the core portion.

To make the enclosures 12c and 12d of the discharge devices of these embodiments, a phosphor film composite is first applied to the interior surfaces of the enclosures.

Such phosphor film compositions are well known, and typical compositions are described in Repshe, September 3, 1974.
r), etc., in US Pat. No. 3,833,392.

This composite contains an organic binder that provides tack, and after application of the composite, the enclosure must be annealed at a relatively high temperature to burn off the organic binder.

For example, a temperature of 525° C. or higher is required.

After the envelope is annealed and treated with a phosphor film, the envelope is cooled, dried, and evacuated to remove any gases or other impurities it may contain.

The drying temperature is usually 450°C.

Alternatively, annealing and drying can be performed as one step.

The heated envelope is further evacuated and a small amount of discharge sustaining filler 14, such as mercury, and a low pressure inert ionizable ignition gas, such as 1.5 torr of argon, are introduced.

The enclosure is further sealed by sealing off the filling lower 3 as shown in FIGS. 8 and 9.

In the process described above, the enclosure is almost completely processed without exposing the core to the high temperatures necessary for its proper manufacturing process.

Thereafter, an elongated segment of a core based on a high permeability magnetic material is inserted into the hollow passage means.

In the embodiment shown in FIG. 8, this corresponds to core section 74; in the embodiment of FIG. 10, this corresponds to joined sections 92 and 9.
This corresponds to the joint core portion formed by 4.

A separately added elongated core portion (76 in FIG. 8 and 90 in FIG. 10) is joined to the end of the inserted core portion.

When the inserted core part and the further added core part are joined together, a loop is formed, in which case at least a portion of the further added core part protrudes outside the finished envelope.

In this manner, neither the core nor the binder are exposed to the high temperatures required to form the seal, so another advantage is that temperature sensitive cements, such as certain epoxies, can be used.

In this preferred embodiment, at least one of the bonded joints between the core sections preferably includes a thin spacer of a low permeability material such as mica at the joint between the elongate core sections. .

An electric light 10e according to still another embodiment is shown in FIGS. 12 and 13.
Illustrated in the figure is a hollow, elongate, closed loop passageway 98 made of a suitable material such as glass, disposed within the enclosure, with a glass conduit member 100 enclosing the enclosure 12e and providing passageways. It is open to 98.

In this way, the interior of the passageway is isolated from the discharge sustaining medium surrounded by the envelope 12e.

To make such a lamp, first separate core sections 102 and 104 are inserted into two semicircular glass tubes 106 and 108, one of which is secured to glass conduit 100.

The separate core parts are further bonded together with gap means 109 of low magnetic permeability material included in the joint, and the separate glass members are further welded together at their joint 110.

Before attaching the core 18e to these glass members, it is desirable to coat the outside of the glass tube with a phosphor so that the core 18e is not exposed to the high temperatures of annealing.

The core is then inserted into a semicircular glass tube.

In the final step, to dry the lamp 10e, separate core pieces 102 and 104 are applied together with a relatively high temperature adhesive, such as a zirconia-based heat-resistant cement sold under the trademark "Tsuyer Eisen Cement" mentioned above.
It is desirable to fix the

As in the previous embodiment, only a portion of the phosphor film 16 is shown.

FIG. 13 shows a practical example of a lamp 10e, in which the envelope 12e is fitted at its neck into a hollow base adapter means 38e.

As in the previous embodiment, a phosphor 16 is applied to the inner surface of the enclosure 12e, and mercury 14, which is a discharge sustaining filler, is provided.

The winding 22e1, the starting winding 40e, the power source 25, and the cap 36 are substantially the same as in the previous embodiment.

FIGS. 14 and 15 show the above-mentioned U.S. Patent No. 4.00.
Discharge device 1 whose structure almost corresponds to that shown in No. 5,330
0f is shown, except that the magnetic core is not formed as a closed loop and separate core portions 112 and 1
The difference is that it is formed as 14.

The core portions 112 and 114 are bonded together at their joints to create a low permeability gap 116 and then together form a composite core 18f.

Winding 22f is wound around core portion 114.

In this embodiment as well, it is desirable to bond the separated core portions with the aforementioned heat-resistant cement containing zirconia as a matrix so that the bonded portions of the cores are not damaged while the lamp is being dried.

Using these separate core parts facilitates manufacturing.

This is because the glass conduit 1 passing through the center of the core 18f
18 because it is sealed to both sides of the recess 120 of the enclosure before the core portions are placed thereon and adhered together.

A phosphor film 16 is applied to the curved portion 120 of the lamp thus created.

In the electric lamp 10f shown in FIG. 15, the core 18f
The curved portion 120 to which is attached is fitted into the neck of the envelope 12f and is tightly attached.

As in the previous embodiment, a hollow cap adapter 38f is fitted into the neck of the enclosure 12f and contains a power supply 25 connected to a conventional screw cap 36.

A phosphor film 16 is applied to the inner surface of the enclosure 12f, and contains a small amount of mercury 14.

In the embodiments of Figures 8-15 described above, any exhaust problems that occur to the core during operation of the lamp are resolved.

Also, in these embodiments, the core can be spared from exposure to lamp drying temperatures and phosphor annealing temperatures, so that the low permeability gap means provided in accordance with the present invention can be made using conventional cements such as epoxy cements. can be provided by simply joining low magnetic permeability disks between separate core sections.

This is because the joints between the separate core sections are not exposed to ultraviolet light or the temperatures required in the light manufacturing process that would degrade the organic cement.

Therefore, by making the core into separate parts and further integrating them by a low permeability gap, the performance of the discharge device can be greatly improved.

In any of the embodiments described above, the dimensions of the low permeability gap can be precisely determined and the magnetic permeability of the gap is very stable.

These low-permeability gap members are the primary factor in determining the effective permeability of the composite core, so the discharge device can be easily regenerated and its performance under changing operating conditions is limited by closed-loop magnetic Compared to other similar discharge devices using cores, the stability is improved.

Although mercury is preferred as the discharge sustainer, other discharge sustainers may be used, such as a combination of cadmium and an inert ionizable starting gas.

[Brief explanation of drawings]

Fig. 1 is a partial cross-sectional schematic diagram of the configuration of the electrodeless discharge device of the present invention, Fig. 2A is an equivalent circuit diagram of the electrodeless discharge device of the present invention, and Fig. 2B is a simplified version of Fig. 2A. circuit diagram,
FIG. 3 is a front view, partially in section, of an actual embodiment of an electrodeless discharge device in which the gapped core is completely contained within the enclosure, and FIG. 4 is a front view, partially in section, of the discharge device shown in FIG. A circuit diagram showing a high frequency exciter/oscillator and an AC/DC converter power supply used for energizing. FIG. 6 is another circuit diagram showing a high frequency exciter/oscillator and an AC/DC converter power source for energizing the discharge device as shown in FIG. 5, and FIG. 7 is a front view shown in cross section. FIG. 8 is a partially sectional front view of still another embodiment, and FIG. A diagram showing a partial cross section,
Fig. 9 is a partially sectional front view of an electrodeless discharge device incorporating the enclosure and core shown in Fig. 8, and Fig. 10 is a partially sectional view of yet another embodiment in which the enclosure and core are further modified. Figure 11 is a partial cross-sectional front view of an electrodeless discharge device incorporating the envelope and core shown in Figure 10, and Figure 12 is a still further implementation in which the envelope and core are further modified. FIG. 13 is a partially sectional front view of an electrodeless discharge device incorporating the envelope and core of FIG. 12, and FIG. 14 is a diagram showing a further modification of the envelope and core. FIG. 15 is a front view, partially in section, of an electrodeless discharge device incorporating the envelope and core of FIG. 14. 10... Electric lamp, 12, 12a... Encapsulation, 14... Discharge sustaining medium, 16... Fluorescent layer, 18, 18a...・・Core, 20, 20a
...Gap, 22...Winding, 24.24
a...Introduction member, 26...Exciter, 2
5... Radio frequency power supply, 32... Neck,
40...Additional winding, 60...Heat conductive metal means, 62...Heat radiation means, 64...
Heat transfer means. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

Claims: 1. Designed to operate at a rated power consumption when energized by a predetermined radio frequency energy such as that produced by a radio frequency power source, and the radio frequency power source is designed to operate at a predetermined power consumption to be operated. An electrodeless discharge device comprising a tuned circuit having a resonant frequency approximately equal to a radio frequency at the output section, the electrodeless discharge device comprising: a sealed, light-transmitting spherical enclosure of predetermined dimensions; a discharge sustaining medium within the enclosure; a phosphor layer provided on the inner surface of the enclosure; a core mainly composed of a magnetic material of high magnetic permeability and including narrow gap means of a low magnetic permeability material across its cross section; a winding wound around the core a predetermined number of times; and a winding connected to the radio frequency power source. an introduction member for connection, the core forming a part of the tuned circuit output section of the radio frequency power source, and the magnetic permeability of the core configured to change the resonant frequency of the tuned circuit output section. and during operation of the electrodeless discharge device, radio frequency energy passing through the windings generates a radio frequency electromagnetic field through and in the vicinity of the core within the enclosure to stimulate the discharge sustaining medium. and emit short wavelength radiation, and the phosphor layer generates visible light that is transmitted through the envelope in response to the short wavelength radiation, and during operation of the electrodeless discharge device, the The gap means of the core stabilizes the effective magnetic permeability of the core so that even if the magnetic permeability of the main material of the core changes greatly, the effective magnetic permeability of the core with the gap changes only slightly. stabilizes the operating resonant frequency of the tuned circuit output by stabilizing the operating resonant frequency of the tuned circuit output, and furthermore, the gap means in the core improves the tuning compared to the Q of other similar tuned circuits incorporating cores formed entirely from the primary core material. An electrodeless discharge device that substantially increases the Q of the circuit to substantially increase the selectivity of the tuned circuit output and suppress output harmonics of the resonant frequency of the tuned circuit output. 2. The electrodeless discharge device according to claim 1, further comprising means for ionizing the discharge sustaining medium contained within the enclosure in order to start operation of the discharge device. 3. An additional winding having a predetermined relatively large number of turns is fixed on the core, the additional winding terminating within the envelope at ends spaced a predetermined distance apart, and the tuning circuit When first energized, the additional winding develops a relatively high voltage between the spaced ends, and the capacitive coupling between the spaced ends of the additional winding within the enclosure The electrodeless discharge device according to claim 2, wherein the discharge sustaining medium is ionized to start the operation of the discharge device. 4. The electrodeless discharge device according to claim 1, wherein the magnetic material with high magnetic permeability is ferrite. 5. The electrodeless discharge device of claim 1, wherein the core has an effective magnetic permeability of at least 200. 6. An electrodeless discharge device according to claim 1, wherein an additional phosphor is applied as a coating on the surface of the core. 7. A thermally conductive metal means is attached to said core in a thermally conductive manner, a heat dissipation means is disposed external to said enclosure, and a heat transfer means is attached to said thermally conductive metal means and within said enclosure. 2. The electrodeless discharge device according to claim 1, wherein the electrodeless discharge device is airtightly connected to the heat radiating means, and transmits heat generated from the core to the outside of the enclosure. 8. The electrodeless discharge device of claim 1, wherein the enclosure has an elongated neck extending therefrom, and wherein the radio frequency power source is attached to the neck of the elongated enclosure. 9 additional discharge means are located outside the enclosure, the radio frequency power source is mounted within a metal container, and additional heat transfer means are connected to the metal container for the power source and the additional heat dissipation means; An electrodeless discharge device according to claim 8.