AXIALLY AND RADIALLY ADJUSTABLE LANTERN

• US 3,648,045 A
• Filed: 04/23/1969
• Issued: 03/07/1972
• Est. Priority Date: 04/23/1969
• Status: Expired due to Term

• Current Assignee: Allan D. Le Vantine, Glen D. Benskin
• Original Assignee: Allan D. Le Vantine, Glen D. Benskin
• Inventors: Le Vantine, Allan D., Benskin, Glen D.
• Primary Examiner(s): Matthews, Samuel S.
• Assistant Examiner(s): Gellner, M. L.
• Application Number:
  US04/818,654
• Time in Patent Office: 1,049 Days
• Field of Search: 240/10.6,11.4,44.2
• US Class Current: 362/265
• CPC Class Codes: F21L 2/00 Systems of electric lighting devices systems employing both electric and non-electric light sources or exchangeable light sources F21L27/00
• CPC Class Codes: F21S 8/003 Searchlights, i.e. outdoor lighting device producing powerful beam of parallel rays, e.g. for military or attraction purposes searchlights mounted on a vehicle B60Q1/245
• CPC Class Codes: F21V 19/02 with provision for adjustment, e.g. for focusing

Abstract

A portable handheld searchlight for providing a high-intensity beam of electromagnetic radiation for comparatively long periods of time from a self-contained, easily portable power source. A Xenon gas discharge lamp is utilized as the source of electromagnetic radiation in the searchlight and it is reflected therefrom by a conventional parabolic reflector. Mechanical adjustments are provided for moving the Xenon lamp along the axis of the parabolic reflector to points closer thereto and further therefrom than a focal point of the parabolic reflector to vary the dispersion or divergence of the reflected beam. A radial adjustment for positioning the Xenon lamp along the axis, which adjustment is generally only made once at the time of manufacture, may also be provided. A light shield comprising a cylindrical tubing around the Xenon lamp is also incorporated as part of the structure to intercept the electromagnetic radiation emitted from the lamp that has not been reflected from the reflector and allows transmission thereof only in directions substantially parallel to the axis of the reflector. A complete electrical power supply system including a battery for providing electrical energy, and circuitry for providing the functions of comparatively high voltage for starting or igniting the gas discharge lamp and intermediate parallels of electrical energy to the lamp after ignition but prior to steady state operation, and also electrical energy of a comparatively low voltage for sustained steady state operation.

Claims

1. An improved portable searchlight arrangement comprising, in combination:

a case means;

a source of electromagnetic radiation having a forward electrode and a rear electrode spaced from said forward electrode for emitting electromagnetic radiation in a preselected distribution, and said emitted electromagnetic radiation having energy in a preselected bandwidth;

reflector means coupled to said case means for support therein in a predetermined position, and comprising a parabolic reflector means having a predetermined focal point on a preselected axis thereof, and adjacent said source of electromagnetic radiation for receiving a first portion of said electromagnetic radiation in said preselected distribution and reflecting said first portion of said electromagnetic radiation therefrom in a first preselected directional pattern;

mounting means for supporting said source of electromagnetic radiation at preselected positions in spaced apart relationship to said reflector means, and said predetermined focal point comprising one of said preselected positions, and said mounting means comprising;

an electrically conductive forward spring clip means coupled in Electrically conductive contact with said forward electrode of said source of electromagnetic radiation for sliding, frictional retention of said source of electromagnetic radiation for the condition of movement of said source of electromagnetic radiation in first portions of said preselected positions; and

an electrically conductive rear clip means coupled in electrically conductive contact with said rear electrode of said source of electromagnetic radiation;

shield means adjacent said source of electromagnetic radiation for intercepting a second portion of said electromagnetic radiation in said preselected distribution to prevent said second portion of electromagnetic radiation from emission in a second preselected directional pattern different from said first preselected directional pattern;

adjustment means on said mounting means for moving said source of electromagnetic radiation into said preselected positions, and said adjustment means comprising;

axial movement means for selectively moving said source of electromagnetic radiation along said axis relative to said shield means and said reflector means to first axial positions closer to and further from said reflector means and said focal point thereof, and said first axial positions comprise said first portion of said preselected positions;

a radial adjustment means coupled to said forward spring clip means and moveably mounted on said case means;

electrically insulating means coupled to said rear clip means; and

said axial movement means coupled to said electrically insulating means;

shield support means for supporting said shield means for movement with said source of electromagnetic radiation for the condition of movement of said source of electromagnetic radiation in second portions of said preselected positions, and said source of electromagnetic radiation moveable with respect to said shield means for movement of said source of electromagnetic radiation in said first portions of said preselected positions;

energizing means connected to said forward spring clip means and to said rear clip means for supplying energy to said source of electromagnetic radiation.

2. The arrangement defined in claim 1 wherein:

said electrically insulating means comprises an electrically insulating screw member and said axial movement means comprises a threaded knob mounted on said case means and threadingly engaging said threaded electrically insulating means whereby rotation of said knob moves said electrically insulating means and said source of electromagnetic radiation along the axis of said reflector.

3. The arrangement defined in claim 1 wherein:

said electrically insulating means comprises an electrically insulated bracket member; and

said axial movement means comprises a lever means having a pivot end and a movement end and said electrically insulating bracket means is pivotally coupled to said axial movement lever means intermediate said pivot end and said adjustment end, and said pivot end is pivotally mounted on said case means, whereby movement of said adjustment end of said axial adjustment lever moves said source of electromagnetic radiation along said axis of said reflector.

4. The arrangement defined in claim 1 wherein:

said axial adjustment means comprises three strut members extending from said front spring clip means to said case means, a first and a second of said strut members adjustably coupled to said case means and the third strut member spring-mounted on said case means.

5. An improved portable searchlight arrangement comprising, in combination:

a source of electromagnetic radiation comprising a gas discharge lamp means having a forward electrode and a rear electrode spaced from said forward electrode for emitting electromagnetic radiation in a preselected distribution, and said emitted electromagnetic radiation having energy in a preselected bandwidth, and said preselected bandwidth of electromagnetic radiation is iN the visible portion of the electromagnetic radiation spectrum;

reflector means adjacent said source of electromagnetic radiation for receiving a first portion of said electromagnetic radiation in said preselected distribution and reflecting said first portion of said electromagnetic radiation therefrom in a first preselected directional pattern;

mounting means for supporting said source of electromagnetic radiation at preselected positions in spaced apart relationship to said reflector means, and said mounting means comprising;

an electrically conductive forward clip means coupled in electrically conductive contact with said forward electrode of said source of electromagnetic radiation; and

an electrically conductive rear clip means coupled in electrically conductive contact with said rear electrode of said source of electromagnetic radiation; and

at least one of said forward clip means and said rear clip means comprises a spring clip means for sliding, frictional retention of said source of electromagnetic radiation for the condition of movement of said source of electromagnetic radiation in first portions of said preselected positions;

adjustment means on said mounting means for moving said source of electromagnetic radiation into said preselected positions;

shield means adjacent said source of electromagnetic radiation for intercepting a second portion of said electromagnetic radiation in said preselected distribution to prevent said second portion of electromagnetic radiation from emission in a second preselected directional pattern different from said first preselected directional pattern;

shield support means for supporting said shield means for movement with said source of electromagnetic radiation for the condition of movement of said source of electromagnetic radiation in second portions of said preselected positions and said source of electromagnetic radiation moveable with respect to said shield means for movement of said source of electromagnetic radiation in said first portion of said preselected positions; and

energizing means connected to said forward clip means and to said rear clip means for supplying energy to said source of electromagnetic radiation, and said energizing means further comprises;

alternating current means for applying an AC signal to said gas discharge lamp to ionize the gas therein for establishing an electrically conductive path therethrough to generate an electrical arc therein;

first DC means for applying a first DC signal having a magnitude sufficient to sustain said arc across said lamp;

second direct current means for applying a second DC signal to said gas discharge lamp for providing a preselected power dissipation therein for sustaining said arc;

third direct current means for supplying a third direct current signal less than said first and said second direct current signals across said gas lamp for providing the required thermal energy for electron emission of said gas discharge lamp for stable operation; and

means for selectively switching between said AC signal means, said first DC signal means, and second DC signal means and said third DC signal means.

6. An improved portable searchlight arrangement comprising, in combination:

a source of electromagnetic radiation having a forward electrode and a rear electrode spaced from said forward electrode for emitting electromagnetic radiation in a preselected distribution, and said emitted electromagnetic radiation having energy in a preselected bandwidth;

reflector means adjacent said source of electromagnetic radiation for receiving a first portion of said electromagnetic radiation in said preselected distribution and reflecting said first portion of said electromagnetic radiation therefrom in a first preselected directional pattern;

mounting means for supporting said source of electromagnetic radiation at preselected positions in spaced apart relationship to said reflector means, and sAid mounting means comprising;

an electrically conductive forward clip means coupled in electrically conductive contact with said forward electrode of said source of electromagnetic radiation; and

an electrically conductive rear clip means coupled in electrically conductive contact with said rear electrode of said source of electromagnetic radiation; and

at least one of said forward clip means and said rear clip means comprising a spring clip means for sliding, frictional retention of said source of electromagnetic radiation for the condition of movement of said source of electromagnetic radiation in first portions of said preselected positions;

adjustment means on said mounting means for moving said source of electromagnetic radiation into said preselected positions;

shield means adjacent said source of electromagnetic radiation for intercepting a second portion of said electromagnetic radiation in said preselected distribution to prevent said second portion of electromagnetic radiation from emission in a second preselected directional pattern different from said first preselected directional pattern;

shield support means for supporting said shield means for movement with said source of electromagnetic radiation for the condition of movement of said source of electromagnetic radiation in second portions of said preselected positions, and said source of electromagnetic radiation moveable with respect to said shield means for movement of said source of electromagnetic radiation in said first portions of said preselected positions; and

energizing means connected to said forward clip means and to said rear clip means for supplying energy to said source of electromagnetic radiation, and comprising;

a source of DC electrical energy;

an inverter stage means for converting said DC electrical energy to an AC electrical signal having a first predetermined voltage;

rectifier means for converting said AC signal to a DC signal having a first DC signal voltage;

means for decreasing said first DC voltage to other DC voltages less than said first DC voltage; and

switching means for selectively applying at least said DC signal at said first DC voltage and said other DC signal voltages to said source of electromagnetic radiation.

7. The arrangement defined in claim 10 and further comprising:

means for increasing the voltage of said AC electrical signal to a second AC voltage level greater than said first, and said second AC voltage level provides a starting AC voltage to said source of electromagnetic radiation;

said switching means further comprises means for selectively applying said second AC voltage to said source of electromagnetic radiation;

said rectifier stage comprises a four-diode bridge rectifier;

said inverter stage comprises a first transistor and a second transistor and said first transistor and said second transistor having different transistor characteristics.

8. The arrangement defined in claim 6 and further comprising:

electrical chopper means and spark gap means for generating a high-voltage, AC signal for starting said source of electromagnetic radiation; and

means for selectively applying said high-voltage, AC signal to said source of electromagnetic radiation.

9. The arrangement defined in claim 6 wherein:

said energizing means for supplying energy to said source of electromagnetic radiation further comprises;

DC electrical energy supply means;

electrical chopper and spark gap means operatively connected to said DC electrical energy supply means for generating a high-voltage, AC signal to start said source of electromagnetic radiation;

first capacitor means connected to said source of DC electrical energy and to said source of electromagnetic radiation for supplying a short duration high-DC voltage level to said source of electromagnetic radiation;

said DC electrical energy source means comprises a first battery means having a first voltage and a second battery means having a second voltage approximately one-half said first voltage;

means for applying a DC signal having a voltage equivalent to the sum of said first battery and said second battery to said source of electromagnetic radiation for providing an intermediate level DC signal;

means for applying a DC voltage signal having a voltage equivalent to said first battery to said source of electromagnetic radiation for supplying said low-level DC signal thereto; and

means for sequentially and selectively applying said AC signal, said high-level DC signal, said intermediate level DC signal and said low-level DC signal to said source of electromagnetic radiation.