U.S. patent number 3,593,061 [Application Number 04/801,019] was granted by the patent office on 1971-07-13 for apparatus for increasing the lighting of photoflash discharge lamps.
This patent grant is currently assigned to Nippon Kogaku K. K.. Invention is credited to Takeshi Suda, Kouichi Takahata.
United States Patent |
3,593,061 |
Takahata , et al. |
July 13, 1971 |
APPARATUS FOR INCREASING THE LIGHTING OF PHOTOFLASH DISCHARGE
LAMPS
Abstract
Apparatus for increasing the lighting of photoflash discharge
lamps including terminals for increased lamp lighting employs a
diode, a trigger condenser, voltage dividing resistors and a
synchroswitch in a main lighting circuit and the same components in
a second circuit for the increased lamp lighting. Each diode in the
main and increased lamp lighting circuits is connected in the
positive direction relative to the discharge of its respective
trigger condenser between a point connecting the trigger condenser
to its voltage dividing resistors and a point connecting one side
of the terminal to one side of its respective synchroswitch.
Inventors: |
Takahata; Kouichi (Tokyo,
JA), Suda; Takeshi (Tokyo, JA) |
Assignee: |
Nippon Kogaku K. K. (Tokyo,
JA)
|
Family
ID: |
11831668 |
Appl.
No.: |
04/801,019 |
Filed: |
February 20, 1969 |
Foreign Application Priority Data
|
|
|
|
|
Feb 23, 1968 [JA] |
|
|
13,387/68 |
|
Current U.S.
Class: |
315/241P;
315/241R; 315/238 |
Current CPC
Class: |
H05B
41/32 (20130101) |
Current International
Class: |
H05B
41/32 (20060101); H05B 41/30 (20060101); H05b
037/00 (); H05b 039/00 () |
Field of
Search: |
;315/237,238,239,240,241P,241 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Huckert; John W.
Assistant Examiner: James; Andrew J.
Claims
What I claim:
1. Apparatus for increasing the lighting of photoflash discharge
lamps comprising a first circuit for main lighting and a second
circuit for increased lamp lighting, the first and second circuits
each comprising a trigger condenser, voltage dividing resistors, a
synchroswitch and diode, and each circuit having terminals
connected to its respective synchroswitch for the connection of the
first and second circuits in parallel, each diode in the first and
second circuits being connected in the positive direction relative
to the discharge of its respective trigger condenser between a
point connecting the trigger condenser to the voltage dividing
resistors and a point connecting one side of each circuit's
terminals to one side of its respective synchroswitch.
2. Apparatus according to claim 1 including a monitor circuit in
said first circuit, and further including a main condenser and a
glow tube in each of said first and second circuits; wherein one of
the voltage dividing resistors in said first circuit controls the
operating voltage in the monitor circuit; and wherein the voltages
of the glow tube and of the trigger condenser in each of the first
and second circuits are each respectively controlled by a voltage
dividing resistor in each of said circuits.
3. Apparatus according to claim 2 including a trigger transformer
in each of said first and second circuits; and wherein each trigger
transformer is connected to the opposite side of its respective
synchroswitch.
Description
The invention relates to apparatus for increasing the lighting of
photoflash discharge lamps, and is more particularly directed to
improvements in apparatus of the type having a terminal for the
increased lighting provided in parallel with a synchroswitch.
In the heretofore known systems for increasing the lighting of
photoflash discharge lamps, a terminal for a synchroswitch has been
provided to connect a main lamp in parallel with a synchroswitch
circuit for lamps to furnish increased lighting. By closing the
synchroswitch for the main lamp, light from the synchroswitch
circuit is furnished at the same time for the lamp providing the
increased lighting. Since the synchroswitch circuit is connected in
parallel, the voltage dividing ratio is changed to a considerable
extent when a voltage dividing circuit is used in conjunction with
the synchroswitch circuit. When it is desired to include a monitor
circuit, together with a voltage dividing circuit, the working
point of the monitor also is changed to a considerable extent, and
as a result, overvoltage is impressed upon the main condenser.
Also, where the system includes means for indicating voltage, such
as a neon tube, the voltage for lighting such tube changes to a
substantial extent, and accordingly, the voltage for indicating is
not suitable.
The purpose of the present invention is to overcome the limitations
referred to above. Apparatus is provided to prevent the resistance
value of a voltage dividing resistor from being changed, in which a
trigger is discharged in the positive direction by utilizing the
characteristics of a semiconductor diode, and to connect in
parallel synchrocircuits so that high resistance in the reverse
direction is obtained.
According to the present invention, by connecting each diode
between a point connecting the trigger condenser and the voltage
dividing resistors and a terminal for lamps, of a main lighting
circuit and a second circuit for increased lamp lighting,
respectively, it is possible to light the lamp of the second
circuit without affecting the operating voltages of the monitor and
the voltage indicator.
In accordance with the invention, apparatus for increasing the
lighting of photoflash discharge lamps having a terminal for
increased lamp lighting is arranged in parallel with a
synchroswitch, and a circuit is provided in which a diode is
connected in the positive direction relative to the discharge of a
trigger condenser between a point connecting the trigger condenser
and voltage dividing resistors, and a point connecting one end of
the terminal for the increased lamp lighting and one end of the
synchroswitch.
This invention will be described with reference to an illustrated
embodiment shown in the attached drawing, in which:
FIG. 1 shows apparatus for increasing the lighting of photoflash
discharge lamps comprising a main lighting circuit and a cooperable
second circuit for increased lamp lighting.
As illustrated, the main lighting circuit comprises a DC-DC
converter 1 connected to a power source 2, such as a battery, to
furnish energy to the converter, a switch 3 being positioned
intermediate the converter and the power source. A monitor circuit
4 is provided to control the oscillation of the converter. A main
condenser 5 is connected to conductors extending from each side of
the converter. As shown, a glow tube 6 is provided for indicating
voltage, and voltage dividing resistors 7, 8 and 9 respectively
provided to control the operating voltages of the glow tube 6, the
monitor signal circuit 4, and trigger circuit. A trigger condenser
10, a diode 11, and a synchroswitch 12 are connected to the voltage
dividing resistors as shown. The diode 11 is positioned in the
circuit between the points b and c, with the diode connected in a
positive direction relative to the discharge of the trigger
condenser 10. Terminals 13 and 13a are respectively connected to
the ends or sides of the synchroswitch 12. A trigger transformer 14
is connected to the opposite side of the synchroswitch 12. A
photoflash discharge lamp is indicated at 15. These elements are
connected to one another as shown, and as previously indicated,
constitute the main lighting circuit.
For increased lamp lighting, a second circuit is provided
comprising the elements or components designated 5' through 15'.
These components correspond to or are the same as the components of
the main lighting circuit having the reference characters 5 through
15, respectively. The diode 11' is positioned in the circuit
between the points b' and c', with the diode connected in a
positive direction relative to the discharge of the trigger
condenser 10'. For a power source to charge the main condenser 5'
of the increased lamp lighting circuit, it will be apparent that a
DC-DC converter, an integrating high voltage dry element battery,
or the like, may be used. Also, the power source for this second
circuit may be the same one as used to furnish power for the main
lighting circuit.
By connecting the terminals 13', 13a' of the increased lamp
lighting circuit to the terminals 13, 13a of the main lighting
circuit by means of cords 16, 16a, the light provided by the
photoflash discharge lamp 15', together with the light furnished by
the lamp 15, is provided upon closing the synchroswitches 12,
12'.
When the power source switch 3 is closed to cause the converter 1
to operate, the main condenser 5 of the main lighting circuit is
charged. When charged to a given voltage, monitor circuit 4
operates and the converter interrupts its operation. Under this
condition, and when the synchroswitch 12 is closed, the energy
charged in the trigger condenser 10 is discharged through the diode
11 and the primary side of the trigger transformer 14 causing the
trigger circuit to operated and the photoflash discharge lamp 15 to
be lighted. When the terminals 13, 13a of the main lighting circuit
are connected to the terminals 13', 13a' of the increased lamp
lighting circuit, as by the cords 16, 16a, increased light is
simultaneously furnished by the photoflash discharge lamp 15' upon
the closing of the synchroswitch 12'.
The significance of the presence of the diodes 11, 11' in the main
lighting and increased lamp lighting circuits will be apparent from
the following. When the terminals 13, 13a and the terminals 13',
13a' are connected by the cords 16 and 16a, the voltage dividing
circuit of the main lighting circuit or side and the voltage
dividing circuit on the increased lamp lighting circuit or side are
connected in parallel. Accordingly, the resistances in series of
the voltage dividing resistors 8 and 9 and of the voltage dividing
resistors 8' and 9' result in resistance values which are
respectively halved. Therefore, the charging voltage in the trigger
condensers 10 and 10' drop to a substantial extent, and it becomes
impossible to obtain enough trigger pulses to discharge the
photoflash discharge lamps 15 and 15'. Also, the signal voltage
from the voltage dividing resistor 8 drops to a considerable extent
so that the working point of the monitor circuit 4 ascends to
impress overvoltage on the main condenser 5. As a result, the main
condenser would incur damage.
On the other hand, when a diode is connected to the trigger
condenser and the synchroswitch in each of the main lighting and
increased lamp lighting circuits, as above described, and when the
synchroswitches of the two circuits are connected in parallel, the
discharge current of the trigger condenser in each circuit is
discharged through the primary side of the respective circuits
without difficulty, utilization being made of the positive
directional characteristic of each of the diodes. Due to the
relationship of the voltage dividing resistors 8 and 9 in the main
lighting circuit and the voltage dividing resistors 8' and 9' in
the increased lamp lighting circuit, the diode 11' will turn to the
reverse direction and diode 11 will turn to the reverse direction
so that there is no flow of current, and no variation will occur in
the operating voltage.
* * * * *