JPS585508B2 - Electrodeless discharge device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates generally to electrodeless lamp devices, and more particularly to electrodeless lamp devices specifically designed to have a relatively constant predetermined operating frequency with minimal output harmonics of the operating (lighting) frequency. The present invention relates to a high frequency electrodeless lamp device.

In recent years, high-frequency electrodeless (H
igh Frequency Electrodele
ss) lamps have been attracting considerable attention.

Fluorescent lamps efficiently convert electricity into light, but they are difficult to handle and require ballasts, which limits their use in the home. Compared to optical lamps, high frequency electrodeless lamps can be made relatively compact.

Anderson April 1, 1977
U.S. Pat. No. 4,017,764, dated No. 2, discloses a fluorescent high frequency electrodeless lamp in which a ferrite core is completely enclosed within a phosphor coated outer bulb.

Column 5, lines 38-43 of this US patent proposes mixing powdered ferrite and polyimide resin in order to reduce the magnetic permeability of the core.

Hollister March 1, 1977
U.S. Pat. No. 4,010,400 discloses a high frequency electrodeless lamp that utilizes a ferrite core as part of the tuned circuit output for a radio frequency energization source.

U.S. Pat. No. 4,005,330, issued January 25, 1977, to Glascock et al.
A high frequency electrodeless lamp is disclosed in which a closed magnetic core is located outside the atmosphere of the outer envelope but in an energy transferring relationship to the atmosphere within the outer envelope.

Anderson, U.S. Pat. No. 3,987,335, dated October 19, 1976, states:
A fluorescent high frequency electrodeless lamp is disclosed in which a ferrite core is housed only partially within an outer bulb coated with a phosphor.

U.S. Pat. No. 3,908,264 dated September 30, 1975 to Frieberg et al.
A high permeability core is disclosed that forms part of a tuned circuit in which the resonant frequency of the circuit is determined by removing a portion of the core.

Kalbfell September 2, 1964
U.S. Pat. No. 3,150,340, dated No. 2, discloses a toroidal core for a high Q value coil that includes a void to give the coil a high Q value.

U.S. Pat. No. 1,813,580 to Morrison, July 7, 1931, discloses an early electrodeless discharge lamp in which the discharge was sustained by a magnetic field formed by a magnetic coil. There is.

According to the present invention, an electrodeless discharge device is provided that operates (lights up) at a rated power consumption when energized with predetermined radio frequency energy generated by a radio frequency power supply.

The power supply has an output with a tuned circuit having a resonant frequency close to a predetermined radio frequency at which the electrodeless discharge device is to operate.

This electrodeless discharge device comprises a sealed, light-transparent outer envelope of predetermined dimensions, preferably round or spherical, enclosing a discharge sustaining medium and having a phosphor layer applied to its inner surface.

A magnetic core, such as a ferrite, is operatively arranged in such a relationship that it can transfer energy to the atmosphere within the outer tube, and the ferrite material that is the main component of the core has a very high magnetic permeability. There is.

The core is loop-shaped and, according to the invention, the basic core is cut to include narrow gap means of low magnetic permeability material across the cross-section of the core.

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

The core forms part of the tuned circuit output portion of the radio frequency power supply.

The electromagnetic modulus of the core constitutes the main variable by which the resonant frequency of the tuned circuit output can be varied.

During operation of the electrodeless discharge device, the gap means in the core stabilizes the effective magnetic permeability of the core such that the total effective magnetic permeability of the gapped core changes only slightly even if the permeability of the main material of which the core is made changes considerably. Try not to.

By doing this, the operating resonant frequency of the tuned circuit output section is stabilized, and in order to greatly increase the selectivity of the synchronized circuit output section and suppress the output harmonics of the resonant frequency, a similar method without using a gap is required. The core spacing means can significantly increase the Q value of the tuned circuit.

According to the present invention, there is also provided a method of manufacturing an electrodeless discharge device in which the core portion is not exposed to the maximum temperature required to process the electrodeless discharge device and the outer bulb.

Next, the present invention will be described in detail with regard to embodiments of the present invention based on the accompanying drawings.

In FIG. 1, a lamp (electrodeless discharge device) 10 generally includes a sealed, optically transparent spherical outer bulb 12 of predetermined dimensions.

This outer bulb 12 contains a discharge sustaining medium, such as a small amount of mercury 14 and a few torr of argon, similar to a conventional fluorescent lamp.

The inner surface of the outer bulb is provided with a layer 16 of phosphor.

A core 18 is provided within the outer tube 12.

The core 18 is mainly formed of a magnetic material with high magnetic permeability,
It has a loop shape with a predetermined size.

In a particular embodiment, the core is toroidal in shape and, according to the invention, the core 18 has a narrow gap 2 of low permeability material, such as mica, across the cross-section of the core.
Contains 0.

A winding 22 having a predetermined number of turns is wound around the core, and the winding 22 is connected to a radio frequency power source 25 by a lead-in conductor 24 .

This power supply 25 is an AC-DC power supply (current device) 28 operated by a standard 115V AC 60Hz line.
It is also equipped with a high frequency drive/oscillator 26.

In operation of the lamp shown in Figure 1, when the lamp is energized, a radio frequency electromagnetic field formed in and around the core within the outer bulb excites the discharge sustaining medium to emit short wavelength radiation. radiate.

This radiation excites the phosphor layer to emit visible light.

This visible light passes through the outer tube 12.

Electrically, the ferrite core 18 can be considered as a transformer having an N-turn winding 22 on the primary side, one turn on the secondary side, that is, a discharge, and the load is the equivalent lamp resistance RL.

FIG. 2A shows a circuit in which the lamp voltage is VL, and FIG. 2B shows a further simplified version of this circuit.

During lighting, the lamp load is approximately H2RL at the coil 22.
(Ω).

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

These circuits are self-oscillating and operate in class A, class B or class 0 modes, giving good efficiency and power output in class B or class 0 codes.

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

An improved circuit is shown in Japanese Patent Application No. 55-19784, which is made very compact and operates very efficiently in class B mode.

Given the lamp core gas shape and composition, the operating voltage VL of the lamp is defined within very narrow limits.

During class B or class C operation, the effective voltage VC across the primary winding of a particular lamp, as discussed below, is approximately 0.707 VDO, in this case 113 VRMS.

The winding of the primary winding 22 of the ferrite core is N=VC/V
L=0.707VDC/VL.

Effects of changes in magnetic permeability of the core Due to temperature changes in the lamp during operation and manufacturing changes during the manufacture of the ferrite core, the magnetic permeability of the core changes.

For the equal circuit shown in FIG. 2B, the resonant frequency fo of that circuit is given by the following equation.

Here, L is the inductance of the coil 22 [Henry]
and C is the tank capacity [farad].

L is calculated as follows. Here, N is the winding, μ' is the effective magnetic permeability, AC is the cross-sectional area of the core [cm2], and LC is the magnetic path length of the core [cm].

In order to determine the influence of changes in the magnetic permeability of the main material constituting the core, the magnetic permeability of a core made of ferrite formed as a completely closed loop can be defined as μC.

If the core is provided with a narrow gap of low permeability μA material such as mica across its cross-section, the effective permeability of the core changes to μ′, where μC and μ′ are They have a similar relationship.

Considering an actual example, the outer diameter is 6.096 cm and the inner diameter is 3.55 cm.
For a commercially available ferrite core of toroidal shape with 6 cm and a thickness of 1.27 cm, the typical permeability of ferrite μC is 5,000 and the effective cross-sectional area AC is 1.
576 cm2, and the average magnetic path length lC is 14.43 cm.
It is.

If μA = 1 and a mica gap of 0.015 cm thickness is provided in the core, the effective magnetic permeability of the core is 5, as obtained by substituting the above value into the permeability equation (■).
,000 to 806.8.

Consider the effect on the effective permeability of the gap size core when the actual permeability of the main material forming the core, ie ferrite, changes or decreases by 20%.

The actual permeability of ferrite decreases by 20%, i.e. 50
When decreasing from 00 to 4000, by substituting that value into the above-mentioned effective permeability equation (■), it can be seen that the effective permeability of the gapped core becomes 775.5.

From this, the actual magnetic permeability of ferrite material is 20%.
It can be seen that due to this change, μ', ie, the effective magnetic permeability of the core, changes by 3.9%.

Thus, by providing a narrow gap in the core, changes in the magnetic permeability of the ferrite material due to manufacturing variations or temperature or both have a very small effect on the actual or effective magnetic permeability of the gapped core.

Effect of the stabilized magnetic permeability of the core on the resonant frequency of the tuned circuit As mentioned above, the core forms part of the tuned circuit output part of the radio frequency power supply, and its resonant frequency is determined by the above formula .

For a core with 22 turns and an effective permeability of 806.8, its core inductance is calculated to be 534 μH.

Typical values for capacitors used in tuned circuits are 500
0 μF, giving a resonant frequency to the tuned circuit of 97.4 KHz (see equation (I)).

In practice, this is a highly desirable operating frequency for good power transfer and limited discharge with limited core electrical losses.

When using the previous example where the effective permeability of the gapped core is reduced to 775.5, the effect on the resonant frequency is only that it increases by 1.99%.

However, if the core had no gap, a 20% decrease in core permeability would increase the resonant frequency of the tuned circuit by more than 10%.

As is clear from this, if a gap is provided in the core,
The resonant frequency of the tuned circuit, which includes the core as a part, is stabilized, which is highly desirable in practical lamp design.

The predetermined operating frequency of the lamp varies considerably within the low radio frequency range, and in practice operating frequencies of the order of 70 KHz to 110 KHz have been found to be highly desirable from the standpoint of minimizing core losses and radiation levels. ing.

Influence of the core with a gap when suppressing the output harmonics of the resonant frequency The inductance LC of the core and the coil without a gap can be determined as follows using the above formula (II), as shown repeatedly.

Here, the windings are 22, μC=5000, AC=1
．． 57.1C=14.43.

Under these conditions, LC=3309 μH.

When an air gap is provided as described above and the effective magnetic permeability of the gap core is 806.8, the inductance LA of the gap core and the coil is 5 according to equation (II).
It is calculated to be 34 μH.

In an equivalent circuit as shown in FIG. 2B, the effective Q value of the tuned circuit is given by the following equation.

For a 40 Watt lamp, typical values for VL are 5 volts and RL is 0.625Ω.

To abrasion (IV) LC=3309μH and LA=534μ
Substituting H, the Q value of the circuit without a gap is 0.149, and the Q value of the circuit with a gap is approximately 0.93.

If the value of Q is low, the selectivity of the tuned circuit to harmonics is very poor, but if Q is close to about 1, the selectivity can be greatly improved, as shown in Table A below. be done.

The efficiency of an output circuit is defined as follows using QU, which is the Q of the circuit with the load removed, and QL, which is the Q of the circuit with the load added.

As an example, QU is equal to 20, and the following table B can be created.

As can be seen from Table B above, a QL of about 1 reduces efficiency by about 5%, but provides a significant improvement in selectivity over a coil with a much lower QL.

Since it is highly desirable to minimize harmonics while maintaining relatively high efficiency, it is desirable to have a Q factor of about 1 for the tuned circuit.

Practical Lamp Embodiment In FIG. 3, the lamp 10 comprises a sealed, optically transparent spherical or pear-shaped outer envelope 12 of predetermined dimensions.

As an example, the height of the outer tube 12 is 6 inches (15, 24 cm
m) with an outer diameter of 4 inches (10.16 cm).

The outer tube 12 is evacuated through a tip tube 30 at its top and provided with a discharge sustaining fill consisting of 1.5 Torr of argon and a small amount of mercury or mercury amalgam 14.

A layer 16 of fluorescent material is formed on the inner surface of the outer bulb 12.

As a specific example, any standard halophosphate salt can be used.

Also, ternary mixtures of rarefied activated phosphorus can be used to provide better temperature dependence.

Phosphorus mixtures of this type are described in U.S. Pat.
No. 937,998.

A core 18, as previously described in detail, is operatively disposed within outer tube 12, the core being comprised primarily of a high permeability magnetic material and having predetermined dimensions and cross-sectional area as previously detailed. It has a loop shape.

Preferably, the core has a toroidal shape for manufacturing convenience, but this shape can be varied in various ways.

Further, as described above, this core 18 includes a narrow gap 20 in the cross section of the core, and around the core 18 there is a narrow gap 20.
A winding 22 with two turns is provided.

The preferred primary material forming core 18 is ferrite, but other magnetic materials may be used in its place.

As is well known, according to the dictionary definition, ferrite is usually formed by treating hydrated ferric oxide with alkali or by heating ferric oxide with metal oxides, and in some cases spinel. NaFeO2 is considered as
Or any number of compounds such as ZnFe2O4.

In particular, the aforementioned ferrite core is manufactured by Electronic Memory and Magnetics Corporation of New Chassis, Keasbey, USA.
& Magnetics Corp., a subsidiary of Indiana General Co., Ltd.
) and is commercially available as the 8000 series, and is available without the above-mentioned gap.

Such ferrite is usually made by a sintering method.

When sintered in a toroidal shape, this ferrite is
It has high magnetic permeability (e.g. 5000) and low electrical resistance (e.g. 100 Ω-cm).

The lead-in conductor 24 is a radio frequency power supply 25 which combines a high frequency drive/oscillator 26 and an AC-DC power supply 28 (shown as a block in FIG. 1) and is located within the elongated neck 32 of the lamp 10. The winding 22 is connected to the

As mentioned above, core 18 is powered by radio frequency power supply 25.
The magnetic permeability of the core is the main variable factor that changes the resonant frequency of the tuned circuit.

Other details of the lamp 10 are of conventional construction, with the three lead-in leads to the coil 22 being connected via a stem 34 to a sealed elongate stem and a power source 25 in the neck.

The power supply 25 is then connected to a conventional screw cap 3 secured to the lamp neck 32 using a cap adapter member 38 formed of a suitable plastic such as phenolic resin.
6.

Preferably 254Ω generated by a low pressure mercury discharge
For the most efficient use of radiation, the core 18 may also be coated with a fluorescent material.

A reflective coating may also be provided on the core and the phosphor layer 16 applied thereon.

Lamp 10 is started by an additional winding 40 on core 18 having a relatively large number of turns.

This additional winding 40 terminates within the outer tube 12 at an end 42 a predetermined distance apart.

In operation of the lamp, when the tuned circuit is first energized, the additional winding 40 develops a relatively high voltage across the spaced ends 42 and, due to the capacitive coupling between them, within the outer tube 12. The discharge sustaining medium of is ionized and starts operation of the lamp.

When the lamp is in operation, the additional winding 40 is effectively removed from the circuit.

As a specific example, the additional winding 40 has 88 turns and the ends 42 are separated by 1 cm or more (eg, 2 cm).

FIG. 4 shows the circuitry used to add the lamp embodiment as shown in FIG.

This circuit includes an AC-DC power supply section 28 consisting of a diode full-wave rectifier 44 and a smoothing capacitor 46, and a high-frequency drive/oscillator 26 consisting of a core section 18, a tuned circuit capacitor 48, and a feedback coil 50. There is.

The feedback coil 50 is one or two turns wound around the core 1B.

An additional starting winding 40 is shown connected to one of the drop-in conductors, although this is not necessary.

The three terminal connection points on lamp stem 34 are shown as reference numeral 52.

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

Capacitor 55 and resistor 57 provide proper biasing to transistor 54.

In the circuit shown in Figure 4, the full-wave rectifier
A direct current of 60 cm is generated.

If the turns ratio is 22:1, this will cause an AC voltage drop of 5μ across the discharge, and the load resistance will be 0.62
In the case of 5 ohms, the lamp discharges with a power consumption of 40 watts.

When using a cool white halophosphate phosphor in this type of lamp, a typical efficiency of 60 lumens/watt was obtained with an additional 17 watts increase in power losses.

It is conceivable that substantially higher efficacy can be obtained by using rare earth-activated fluorophores.

A further lamp embodiment 10a is shown in FIG.

In this embodiment, only a portion of the core 18a is housed within the outer tube 12a.

A 22-turn winding 22 is wound around a portion of the core 18a located outside the sealed outer tube 12a.

However, the 88-turn starting winding 40 has its end 42 for starting the discharge located within the outer tube 12a.

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

A circuit for energizing the lamp of FIG. 5 is shown in FIG.

The terminal connection points between the coils 22 and 50 and the power supply device 25 are as follows:
It is shown as reference number 58.

In other respects the circuit is the same as that shown in FIG.

In this lamp embodiment, the gaps are two separate gaps 20
It is provided as a.

The thickness of each gap 20a is 0.0075 cm.

These gaps 20a are formed by a core 18a passing through the outer tube 12a.
It is located in the part of

Still another lamp 10b is shown in FIG. 7, except that a thermally conductive metal member, such as a copper strip 60, is disposed to conduct heat around the ferrite core 18. is substantially the same as the lamp 10 shown in FIG.

An additional heat sink member 62, such as a heat sink, is fixed to the outside of the lamp base adapter 38b.

A copper strip 60 surrounding the exterior of the core 18 is maintained in thermal communication with a heat sink 62 using additional copper conductor members 64.

As another possible embodiment, a metal container 65 provided for the power supply 25 is maintained in heat transfer relationship with a further heat dissipating member 66 by means of an additional conductor 68 .

In any of the embodiments described above, it is desirable to insulate winding 22 from ferrite core 18.

Such insulation is manufactured by Soureisen Cement Corporation (Saureisen, Pittsburgh, Pennsylvania, USA).
This is facilitated by applying to the core a layer 70 of a heat-resistant inorganic cement, which is a zirconia-based cement sold under the trademark "5auereisen Cement" by Auereisen Cement Co., Ltd.

The typical thickness of this layer 70 is 0.05 to 0.1 mm.
It is.

Other materials that may be used to coat the ferrite core to insulate it from the windings include:
Corning Glass Company
Trademark "Pyroce-ra" by Lass Co.
There is a devitrified glass commercially available as ``M (Pyroceram)''.

A glass or fiberglass insulation layer may also be provided around the winding 22.

Although in the preferred embodiment the gap is described as being formed from mica spacers, other materials such as alumina, zirconia, magnesia, or strontium oxide can be used instead.

Also, it is not necessary to include a spacer in the gap; in this case, the atmosphere within the lamp constitutes the low magnetic permeability material in the gap.

Although gaps reduce the effective magnetic permeability of the core, in lamp embodiments such as those described above, it is desirable that the effective magnetic permeability of the core not decrease below about 200.

Of course, this is considerably lower than the permeability normally obtained with ferrite itself.

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

However, it is highly desirable to use energizing circuits that incorporate tuned circuit outputs, such as those that include a core as part of the tuned circuit, and in such cases the gap provided in accordance with the present invention may be It has the dual effect of stabilizing the frequency and suppressing harmonics.

The embodiment of the lamp described above can be modified in many ways.

For example, the power supply need not be attached to the main portion of the outer bulb, but may be attached separately, such as by a standard screw-in metal fitting that fits into a standard incandescent lamp socket.

The lamp itself is then plugged or otherwise attached to its power supply, so that the lamp or power supply can be replaced separately.

By including a narrow gap of low magnetic permeability in the core, additional benefits are obtained with respect to the lamp device.

For example, if the core is to be physically insulated from the atmosphere within the sealed outer envelope, but operatively arranged to transmit energy to the atmosphere within the outer envelope, and If the core is formed as a closed loop of magnetic material, manufacturing problems arise, such as those outlined in the aforementioned U.S. Pat. No. 4,005,330.

Specifically, in FIG. 4 of that '330 patent, the completed core has a glass sleeve inserted therein which is then fused to a glass inner bend; Attachment is such that the core and inner bend are then sealed to the lamp outer bulb.

According to the invention, when providing a low permeability gap, the core is first made as separate parts and then assembled using cement or adhesive.

Additionally, the core may be insulated from the discharge sustaining atmosphere within the lamp envelope, so that in some embodiments the core portions may be held together using a relatively easy-to-handle adhesive, such as a common epoxy adhesive. Can be joined.

When such adhesives are used on cores exposed to the operating atmosphere within the lamp envelope, the UV radiation generated degrades the epoxy adhesive and its decomposition products adversely affect lamp performance. .

Various embodiments in which the core is physically insulated from the atmosphere within the sealed outer envelope but operatively arranged to transfer energy to the atmosphere within the outer envelope are illustrated in FIGS. show.

These embodiments include lamps obtained by forming the core in separate parts and then combining the parts, preferably including a low permeability gap as part of the joint between the core parts. This is a typical example of the structure.

In the lamp 10c shown in FIGS. 8 and 9, the outer tube 12c has a substantially cylindrical shape;
Two glass passages 70 are provided in 2c.

This passage 70 has a hollow elongated shape and extends in the same direction through the outer tube 12c.

Both ends 72 of these passages 70 are open.

In order to apply the phosphor coating 16, the outer tube 12c is
After applying a phosphor coating and performing treatment to drive out decomposition products of the adhesive material, baking and bleeding the chip tube 7
Complete by injecting the discharge sustaining filler through 3.

Thereafter, the core is inserted through the elongated passageway 70 and mounted so that it can transfer energy to the atmosphere within the treated outer tube 12c.

In such embodiments, core 18c is formed of at least two separate parts.

One part 74 is U-shaped and the other part 7
6 is adapted to be mounted adjacent to both ends of its U-shaped portion 74.

These two parts are joined together using any suitable simple adhesive means, such as ordinary epoxy adhesive, with the gap 7
A low permeability spacing giving 8 may be formed with thin disks of mica packed to join the separate core sections together.

In such embodiments, gap 78 may be formed by a single mica disk, or two disks may be used. Winding 22c is otherwise generally similar to that described above. , and starting is provided by a winding 40c, which is capacitively coupled via the glass wall of the passageway 70.

In other respects, the lamp 10c contains a small amount of mercury 14
This is similar to the previous embodiment including the discharge sustaining agent and phosphor coating 16.

For purposes of illustration, only a portion of the phosphor coating 16 is shown.

An actual lamp 10c is shown in FIG. 9, in which a modified outer tube 12c is attached to a modified hollow base adapter 38c.

This base adapter 38c includes a biasing circuit 25 and is connected to a normal screw-type base 36.

Such a structure can be designed to operate in an orientation such that the passage 70 is positioned vertically to provide a chimney effect through the passage 70 and to allow cooling of the core 18c during lamp operation. , has an additional effect.

In order to facilitate this kind of cooling, hollow base adapter 3 is used.
8c is provided with an aperture 80 and the lamp is also provided with a light-transmissive top cap 82 with an aperture 84 to achieve a chimney effect.

In order to prevent the epoxy adhesive part of the gap 78 from being exposed to the ultraviolet rays generated in the outer bulb 12c during lamp operation, the passage is formed of glass that hardly transmits ultraviolet rays, such as ordinary soda lime glass. Ru.

Alternatively, the inner surface of the outer tube of the passageway 70 may be coated with a conventional ultraviolet reflective material, and this type of coating is well known.

10 and 11, another alternative lamp embodiment 10d is shown, in which the modified outer bulb 12d is sealed against the discharge sustaining medium within the outer bulb. A hollow elongated curved passageway 86 is provided which may be formed of a vitreous material such as light or hard glass.

Both ends 88 of the hollow curved passage 86 are open through the wall of the outer tube 12d, and the inner surface of the outer tube is coated with the phosphor 16.
After treatment to drive out adhesive decomposition products, followed by firing, evacuation and encapsulation with a mercury discharge sustaining filler 14, a suitable low permeability space is provided in at least one of the joints 96. Core 18d is assembled by joining three core pieces 90, 92 and 94 with a suitable adhesive such as epoxy so as to include the core 18d.

For illustrative purposes, only a portion of the phosphor coating 16 is shown.

The starting winding 40d in this embodiment is wrapped around the exterior of the hollow curved passage 86 such that it is magnetically coupled to the core 18a after assembly to facilitate starting the lamp 10d.

An actually assembled lamp 10d is shown in FIG. 11, in which the outer tube 12d is sealed against a hollow base adapter 38d containing the energizing circuit 25.

The energizing circuit 25 includes the winding 22d and the base 3 as described above.
6.

In the lamp embodiments shown in FIGS. 8-11 and 16-18, the outer bulb is heat treated (lehri).
can be manufactured and processed completely without exposing the core part to the maximum temperatures required for ng).

Referring to FIGS. 8-11, the outer tubes 12c and 12d are made of a light-transmissive material such as glass and can be evacuated and sealed.

Inside the outer tube, there is a hollow conduit type passage (70 in Fig. 8;
86) in the figure, and reference number 7 in FIG.
2. The ends of the passageways, designated by reference numeral 88 in FIG. 10, are sealed against and open through different portions of the wall of each outer tube.

Each end of the passage remains open to allow later insertion of the lamp core portion.

Outer tube 12c formed for these lamp embodiments
and 12d, a phosphor coating composition is first applied to the inner surface of the outer tube.

Phosphor coating compositions of this type are well known in the art, and a representative example is Re-psher.
) et al., U.S. Patent No. 3.833,3 dated September 3, 1974.
It is described in the specification of No. 92.

This type of composition contains an organic binder that imparts viscosity, and after the composition has been deposited, the outer tube must be heated to a relatively high temperature in order to decompose and burn out the organic binder. There is.

As an example, temperatures of 525° C. and above are required.

After heating the outer tube to complete the phosphor coating process,
The outer tube is cooled, fired and evacuated to remove occluded gases and other impurities.

This firing temperature is usually 450°C. Moreover, heating and baking can be performed in one step.

The heated outer tube is then evacuated to 1.5 Torr (to
A low pressure inert ionizable starting gas such as argon (rr) and a small amount of discharge sustaining filler such as mercury 14 are enclosed.

The outer tube is then hermetically sealed by cutting off the fill tube (tip tube), as shown at 73 in FIGS. 8 and 9.

In a process such as that described above, the outer bulb is almost completely treated without exposing the core portion of the lamp device to the temperatures necessary for proper outer bulb treatment.

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

In embodiment 10c shown in FIG. 8, this is the core portion 74, and in embodiment 10d shown in FIG. be.

An additional elongate segment of the core, such as segment 76 as shown in FIG. 8 or segment 90 as shown in FIG. 10, is then glued to the end of the inserted core segment.

The insert core segment and the additional core segment glued together have a loop shape with at least a portion of the additional core segment projecting outside the outer tube.

In this way, neither the core nor the segment joints are exposed to the high temperatures required for outer tube processing, and adhesives that degrade with temperature, such as some epoxies, can therefore be used. Additional effects can be obtained.

In a preferred embodiment, at least one of the bonded joints between the core segments includes a thin spacer of low magnetic permeability material.

The preferred material is mica, which is included in the joints between the elongated core segments.

FIG. 12 and FIG. 13 show a further example 1 of another lamp.
0e, in this embodiment a hollow elongated closed loop passageway 98 formed of a suitable material such as glass is provided within the outer tube, and a glass conduit member 100 is sealed through the outer tube 12e to open the passageway. Open to 98.

In this way, the interior of the passageway is separated from the discharge sustaining medium surrounded by the outer tube 12e.

To make such an embodiment, first separate core parts 1
02 and 104 are two semicircular glass tubes 106 and 10
8.

A glass conduit member 100 is attached to one of the glass tubes.

These separate core members are then glued together including gap means 109 of low magnetic permeability material at their joints, and the separate glass members are bonded together at their joints 11.
0 to be fused together.

Before attaching the core 18e to these glass members, it is desirable to apply a phosphor coating to the outside of the glass tube so that the core 18e is not subjected to heat treatment temperatures.

The core is then inserted into the semicircular tube.

To facilitate lamp firing during the final manufacturing step, relatively high temperature adhesives such as the aforementioned refractory zirconia-based adhesive sold under the trademark SauereisenCement may be used. Preferably, adhesive secures the separate core pieces 102 and 104 together.

As in the previous embodiments, only a portion of the phosphor coating 16 is shown.

An embodiment of a lamp 10e is shown in FIG. 13, in which the outer bulb 12e is sealed at its neck with hollow base adapter means 38e.

As in the previous embodiment, the inner surface of the outer bulb 12e is provided with a phosphor coating 16 and a discharge sustaining filler of mercury.

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

FIG. 14 and FIG. 15 show a modified lamp device 10f.
This lamp device 10f is substantially the same as the configuration shown in the above-mentioned US Pat. No. 4,005,330 except for the following points.

That is, the magnetic core is formed as separable core portions 112 and 114 rather than as a closed loop.

These core portions 112 and 114 have a low permeability gap 1
16 to form a composite core 18f.

The core portion 114 is provided with a winding 22f.

Even in such embodiments, it is desirable to bond the separate core portions together with the refractory zirconia-based adhesive described above to prevent damage to the bonded portions of the core during lamp firing.

The use of separate core parts simplifies the manufacture of the lamp.

This is because the glass conduit 11 passing through the center of the synthetic core 18f
8 can be sealed to the side of the inner tube part 120 before fitting and gluing the core part thereon.

In the assembled lamp, the curved portion 120 is provided with a fluorescent coating 16.

A manufactured lamp 10f is shown in FIG. 15, in which a circular portion 1 with a core 18f attached
20 is sealed at the neck of the outer tube 12f.

Similar to the embodiment described above, the hollow base adapter 38f is
It is sealed at the neck of the outer tube 12f and includes a power source 25 connected to a conventional screw cap 36.

The inner surface of the outer tube 12f is coated with a phosphor coating 16 and contains a small amount of mercury.

In both of the embodiments shown in FIGS. 8-18, the outgassing problems encountered by the core during lamp operation are eliminated.

Also, in those embodiments where the core is not exposed to lamp firing temperatures and phosphor heat treatment temperatures, the low permeability gap means provided in accordance with the present invention may be applied to conventional adhesives such as epoxy adhesives. It can be simply provided by gluing the low magnetic permeability disk means in place between the separate core sections using a compound.

This is because the joints between the separate core sections are not exposed to the temperatures required for lamp processing or to ultraviolet radiation that would degrade the organic adhesive.

Accordingly, the performance of the lamp device can be greatly improved by forming the core as separate pieces that include a low permeability gap and can be secured together as a unitary piece.

In both of the embodiments described above, the dimensions of the low permeability gap can be very carefully controlled and the 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, making the lamp device easily reproducible and providing stability-related performance under a variety of operating conditions. improved compared to other similar lamp devices containing magnetic cores.

Although mercury is the preferred discharge sustaining material, other discharge sustaining materials may be substituted, for example cadmium plus an inert ionizable starting gas.

A further lamp embodiment 10g is shown in isometric view in FIG.

In this embodiment, the outer tube portion 12g is substantially cylindrical and is provided with a hollow elongate conduit-like passageway means 122 extending axially through the outer tube 12g, the end 124 of the passageway means 122 being It is sealed with an end wall 125 of the cylindrical outer tube 12g,
It is open through there.

In such a configuration, the atmosphere within the passage means 122 is insulated and sealed from the atmosphere within the outer tube 12g.

As in the previous embodiment, a phosphor layer 16 is provided on the inner surface of the outer bulb 12g, and the atmosphere inside the outer bulb is similar to that of the lamp 1.
To form a discharge sustaining atmosphere when 0g is energized,
Contains a small amount of mercury 14 and a low pressure inert ionizable starting gas.

In such a configuration, the outer bulb portion 12g of the electrodeless discharge lamp device is coated with a phosphor via a suitable tip tube (filling tube) 126, heat treated, evacuated, and filled with a discharge sustaining medium. The tip tube 126 is then made by squeezing it to obtain a sealed, complete outer tube.

In FIG. 16, only a portion of the phosphor layer 16 is illustrated.

After forming the outer bulb, the lamp assembly passes through the passage means 122 to the segmented portion 12 of the deformed ferrite core 18g.
Complete by inserting 8.

The remainder of the core 130 is secured to its inserted core portion 128 by a suitable adhesive such as an epoxy or other retention means such as a mechanical clamping mechanism.

As in the previous embodiment, a starting winding 40g is wound around the segment 12B of the core which projects through the passage means 122, and a power winding 22g for the core.
is connected to the radio station frequency power supply 25 via a suitable lead-in conductor 24g.
It is connected to the.

A suitable base adapter 38g made of plastic is attached to the outer tube 12g, and a suitable base 36 for energizing the lamp is attached.

In the illustrated embodiment, the core 18g is connected to the joint 13
2 and is formed of four separate segments secured together by suitable retaining means or adhesive.

As in the previous embodiments, in order for the lamp device to obtain the best performance, it must be
A low permeability spacer across the cross-section of the core forms a gap 133.
It is desirable that at least one of the joint portions 132 include the following.

However, in the case of some oscillators, such as class D oscillators, the gap means 133 of low permeability material can be omitted and each core segment is fixed directly to each other.

In such embodiments, the outer tube is fully formed without exposing the core to high outer tube heat treatment temperatures, and if adhesives are used to join the core segments together, which could degrade. If desired, this adhesive can easily protect against the harmful effects of ultraviolet radiation generated within the outer bulb during lighting.

The outer core 18g of the outer tube 12g is preferably provided with a light reflective coating 134 to minimize light absorption.

Embodiment 10 of yet another lamp is shown in FIGS. 17 and 18.
h is shown.

In this embodiment, a single conduit passageway 122h extends through the outer tube 12h so as to define a relatively narrow spacing between the passageway 122h and the proximal wall portion 135 of the outer tube 12h.

Looped core 18h is configured to extend through passageway 122h and around the exterior of outer tube wall portion 135 proximate passageway 122h.

In this manner, the core is either physically isolated from the atmosphere within the sealed outer envelope or operatively positioned to transfer energy to the discharge sustaining atmosphere within the outer envelope 12h.

As in the previous embodiment, the core comprises at least two separate segments 136 held together by a suitable adhesive such as an epoxy adhesive or a suitable retention means such as a mechanical clamp at the core joint 139. and 138.

As in the previously described embodiment, starting winding 40h is wound around core segment 136 within passageway 122h.

Power winding 22h is wound around core segment 13B and connected to radio frequency power source 25 via lead-in wire 24h.

A suitable base adapter 38h is fixed to the outer tube,
Projecting therefrom is a suitable screw cap 36 for connecting the lamp to a power source.

Although only a portion of the phosphor layer 16 is illustrated, the discharge sustaining medium consists of a small amount of mercury 14 and a conventional inert ionizable starting gas.

As in the previous embodiment, the outer tube is first formed entirely;
It is sealed with a tip tube 140 at the top.

The ferrite core is then inserted through passage 122h and the lamp can be completed without exposing the core to the operating atmosphere within the outer bulb and the relatively high processing temperatures required to complete outer bulb formation.

Preferably, at least one of the core joints 139 includes a gap means 142 of a low permeability material, such as a mica spacer.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing, partially in cross section, the basic components constituting the lamp of the present invention, FIG. 2A is a simplified circuit diagram of the high frequency electrodeless lamp of the present invention, and FIG. 2B is FIG. 2A. Figure 3 is an elevational view, partially in section, of an embodiment of a high-frequency electrodeless lamp in which the core with a gap is completely housed within the lamp outer bulb. High frequency drive/oscillator and alternating current used to energize the lamp shown.
FIG. 5 is a circuit diagram showing a DC power supply device, FIG. A circuit diagram showing a high-frequency drive/oscillator and an AC-DC power supply device for energizing the lamp shown in Figure 5. Figure 1 shows a heat conductive metal member fixed to a core to transfer heat from the core to an external radiator. Further lamp embodiments may be provided in which additional heat conducting members are provided for transferring heat from the power supply enclosure to an external radiator. The elevational view, FIG. 8, shows, partially cut away, a further embodiment of a lamp in which the core is isolated from the discharge sustaining atmosphere within the outer bulb and the core is in an energy transmitting relationship to the atmosphere within the outer bulb. 9 is an elevational view, partially cut away, of another lamp embodiment incorporating an outer bulb and core as shown in FIG. 8; FIG. FIG. 11 is an isometric view, partially cut away, of the outer tube and core portions of yet another isolated lamp embodiment; FIG. FIG. 12 is an elevational view partially cut away, FIG. FIG. 14 is an elevational view, partially in section, of another embodiment of a lamp incorporating an outer bulb and core portion as shown; FIG. FIG. 15 is an elevational view, partially in section, of a lamp with an inwardly directed outer tube incorporating the core shown in FIG. 14, and FIG. Still another lamp embodiment is partially broken out in which a single passageway is provided for receiving the segment portion of the core and the other portion of the core is looped and held outside the sealed outer tube. The isometric view shown in FIG. 17 shows a single passageway near one end of the outer tube that surrounds a segmented portion of the ferrite core while the other portion of the core loops outside the outer tube. FIG. 18 is an elevational view, partially in section, of yet another embodiment of a lamp which may be disposed within the base portion of the lamp; FIG. 18 is a side view, partially in section, of the lamp shown in FIG. 17; 10g, 10h... Lamp, 12g, 12h.
...Outer tube, 14...Mercury, 16...
...phosphor layer, 18g, 18h...ferrite core, 22g. 22h...Power winding, 24g, 24h...
... Retraction member, 25 ... Radio frequency power supply, 3
6...Base, 38g, 38h...Base adapter, 40g, 40h...Start winding, 1
22... Passage means, 124... End part,
128.130・・・Core part, 132°13
9... Joint portion, 133, 142... Gap means, 134... Reflective coating. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. In a wireless electrode discharge device that operates at a rated power consumption when energized with a predetermined radio frequency energy generated by a radio frequency power source whose output portion is equipped with a tuned circuit having an operating resonant frequency. a sealed optically transparent outer envelope of predetermined dimensions; and hollow elongated conduit-like passage means passing through the outer envelope, the ends of which are sealed to the wall of the outer envelope at different locations and extending therethrough; a discharge sustaining medium constituting the atmosphere within the sealed outer envelope; and a discharge sustaining medium constituting the atmosphere within the sealed outer envelope; a phosphor layer and a magnetic material of high magnetic permeability arranged in a relationship such that it is physically isolated from the atmosphere within the sealed outer envelope but capable of transmitting energy to the atmosphere within the outer envelope; a loop-shaped core having narrow gap means of a low magnetic permeability material across its cross-section as a main component, a predetermined portion of which passes through said passage means, and another portion of said core located outside said passage means; , at least two held together by a retaining means.
a power winding wound a predetermined number of times around another portion of the core; a lead-in member for connecting a line to the radio frequency power source, the core forming part of the tuned circuit output of the radio frequency power source, and during operation of the electrodeless discharge device, the Radio frequency energy passing through the power winding generates a radio frequency electromagnetic field in the outer envelope through the looped core to excite the discharge sustaining medium to emit short wavelength radiation such that the phosphor layer An electrodeless discharge device that emits visible light that passes through the outer bulb in response to the short wavelength radiation. 2. The electrodeless discharge device according to claim 1, wherein the passage means is a single conduit-like passage extending from one wall portion of the outer tube to the other wall portion of the outer tube. 3. The single conduit-like passageway extends through the outer tube with a relatively narrow spacing between it and an adjacent wall portion of the outer tube, and the loop-shaped core extends through the passageway. 3. An electrodeless discharge device as claimed in claim 2, adapted to extend through and around the outside of said outer tube wall portion proximate said passageway.