JP2000241856A - Stroboscopic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stroboscopic device in which short-circuit and the occurrence of noise caused by spark are prevented by insulating processing. SOLUTION: A main capacitor 28 is connected by soldering a copper foil surface forming a pattern of a printed board 24 with a negative terminal 28a and a positive terminal 28b after the terminals 28a and 28b are inserted in an aperture part formed on the board 24. Similarly, a conductive plate 37 is connected by soldering the copper foil surface forming the pattern of the board 24 with a leading end part 37a. The exposing parts of the metallic surfaces and the soldered surfaces of the part 37a, and the terminal 28a whose potentials become the same potential as the high voltage of about 300 V condensed in the capacitor 28 are covered by insulating agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a strobe device, and more particularly to an improvement of a strobe device used in a camera.

[0002]

2. Description of the Related Art As a simple camera, a film unit with a lens pre-loaded with an unexposed photographic film is manufactured and sold by the present applicant. There are various types of this film unit with lens depending on the application.
Among them, those incorporating a strobe device so as to enable photographing in a dark place such as at night or indoors are widely used.

In order to minimize the manufacturing cost of a strobe device incorporated in a film unit with a lens, a printed circuit board on which a circuit pattern is formed holds a light-emitting portion composed of a strobe discharge tube and a reflector, and a strobe light is applied to the circuit pattern. Electrical components such as a main capacitor and a step-up coil for forming a circuit are mounted, and the printed circuit board is incorporated in a film unit with a lens.

In flash photography, the main capacitor is charged, and the terminal voltage of the main capacitor reaches about 300V. Therefore, for example, when a film unit with a lens is wetted with water at the seaside, etc., if water drops enter the flash unit through a gap in the exterior of the film unit with a lens and reach the strobe device, high voltage may be applied depending on the wet location. To the exterior of the film unit with the lens, and the user may be electrocuted.

To prevent such an electric shock accident, refer to
As described in JP-A-239801, it is effective to perform insulation treatment on the surface of a conductive metal component assembled on a printed circuit board. According to this, even if water invades between the metal component and the film unit with lens, the high voltage applied to the conductive plate does not reach the film unit with lens.

[0006]

By the way, recently, with the downsizing of the film unit with the lens, the strobe device has been downsized, and the circuit pattern formed on the printed circuit board has become finer. As is well known, there are locations in the strobe circuit where high voltage is generated by charging the main capacitor, and in circuit design, sparks are not generated from these locations in low-voltage parts near them. When water droplets or the like adhere to the surface, there is a possibility that an abnormal noise may occur due to sparking, or a malfunction may occur due to a momentary short circuit caused by the spark.

[0007] Such a spark is likely to occur particularly at a place where soldering is performed on a printed circuit board. For example,
Even if the surface of the metal component is insulated as described above, its end is soldered to a required portion of the circuit pattern on the printed circuit board, and the solder swells as a conductive portion on the surface of the printed circuit board. Then, a high voltage is applied in a state where water droplets or the like adhere to this portion, and a spark is easily generated when a potential difference between the low voltage portion and the low voltage portion near the portion exceeds a certain level.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a strobe device which does not cause a short circuit or abnormal noise due to a spark even when water droplets adhere to a printed circuit board. Aim. In addition,
The present invention can be applied not only to a built-in film unit with a lens but also to a strobe device for a portable photographic camera or an electronic still camera.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a strobe device according to the present invention provides a conductive device which is exposed at a soldering position between a connection terminal of an electric component and a circuit pattern formed on a printed circuit board. The part is covered with an insulating material.

[0010] The conductive portion also includes a solder surface provided between a connection terminal protruding from the surface of the printed circuit board and a required portion of the circuit pattern. The solder surface is also covered with an insulating material. You had better. Further, as the connection terminal, a conductive piece connected to a terminal of a main capacitor or a terminal of a strobe discharge tube and connected to a circuit pattern of a printed circuit board has a large potential difference from the surroundings and sparks are easily generated. At least one of the connection terminals is always covered with an insulating material.

[0011]

FIG. 2 shows an appearance of a film unit with a lens according to the present invention. The lens-fitted film unit 2 includes a unit main body 3 in which a film cartridge is loaded in advance and various photographing mechanisms are incorporated, and an exterior label sheet 4 partially covering the unit main body 3.

A shutter button 6, a counter window 7, and a light guide 14 are provided on the upper surface of the unit body 3, and a finder 8, a photographing lens 9, an operation button 10 for strobe charging, a strobe light emitting unit 11, and the like are provided on the front surface. I have. Also,
The winding knob 12 is exposed from the rear side. The exterior paper 4 is affixed so as to be wound around a central portion of the unit main body 3, and has an opening for exposing the photographing lens 9, the finder 8, the counter window 7, the light guide 14, and the like to the outside.

As shown in FIG. 3, the unit main body 3 includes a main body base 18 into which the film cartridge 16 is loaded,
An exposure unit 19 and a strobe device 20 are mounted on the front surface of the main body 18, and a front cover 21 and a rear cover 22 are mounted on the front and rear surfaces of the main body 18. Assembled by engagement.

As shown in FIG. 1, the strobe device 20 comprises:
A printed circuit board 24 on which a circuit pattern is formed, and a strobe light emitting unit 11 mounted on the printed circuit board 24;
And a power supply battery 41.

As shown in FIGS. 1 and 4, the strobe light emitting section 11 includes a strobe discharge tube 35 for emitting strobe light,
A reflector 36 for reflecting light emitted from the strobe discharge tube 35 toward a subject, a protector 11a for protecting a front surface of the strobe light emitting unit 11, and a reflex case 1 attached to the printed circuit board 24 while holding these.
1b, a conductive plate 37 which is a conductive member for electrically connecting one electrode 35a of the strobe discharge tube 35 and the pattern of the printed circuit board 24, and the other electrode 35b of the strobe discharge tube 35 and the pattern of the printed circuit board 24. And a contact piece 38 which is a conductive member for electrically connecting the contact pieces 38 to each other.

The connection between the conductive plate 37 and the contact piece 38 and the pattern on the printed circuit board 24 is performed by first inserting the distal end portions 37a and 38a of the conductive plate 37 and the contact piece 38 into openings formed in the printed circuit board 24. Thereafter, the surface of the pattern of the printed circuit board 24 that is not covered with the resist material, that is, the exposed copper foil surface and the tip portions 37a and 38a
Is performed by soldering.

In FIG. 1, on a printed circuit board 24, various electric components such as a main capacitor 28 constituting a strobe circuit described later and a strobe charging switch 29 are provided.
, Synchro switch 30, plus metal contact piece 53,
And a negative metal contact piece 54 are provided. The positive metal contact piece 53 and the negative metal contact piece 54 connect the positive pole 41b and the negative pole 41a of the power supply battery 41 to a strobe circuit.

The main capacitor 28 is connected to the printed circuit board 2.
After the minus terminal 28a and the plus terminal 28b are inserted into the opening formed in 4, the copper foil surface forming the pattern and the minus terminal 28a and the plus terminal 28b are fixed by soldering.

The strobe charging switch 29 includes a metal contact piece 29a disposed on the back side of the charging operation button 10 and a contact portion 29b made of copper foil. The operation button 10 formed of plastic is fixed by the locking mechanism by sliding upward. At this time, the metal contact piece 29a is pressed by the elastic displacement of the operation button 10,
The state is brought into contact with the contact portion 29b, the strobe circuit is closed, and strobe charging is performed. Sync switch 3
Reference numeral 0 denotes a metal switch contact piece, and the exposure unit 1
When pressed by the swinging of the shutter blades incorporated in 9, the two switch contact pieces come into contact with each other to emit strobe light.

A known flash circuit formed on the printed circuit board 24 converts the current of the power supply battery 41 into an alternating current by turning on a flash charging switch 29 and then boosts the current to about 300 V as shown in FIG. After that, a booster circuit 56 for converting the current to DC again and applying it to the main capacitor 28, and a trigger circuit 57 for generating a trigger signal by turning on the synchro switch 30 and causing the strobe discharge tube 35 to emit strobe light are provided. I have.

In assembling the strobe device, an insulating process is performed after the components have been completely assembled by soldering. With reference to FIG. 6, an insulation process performed around the minus terminal 28a of the main capacitor 28 will be described. The minus terminal 28a protruding to the opposite side of the printed board 24 and the copper foil surface 42 forming the pattern are electrically connected by the soldering part 43, and the copper foil surface 4
The outside of 2 is covered with an insulating resist material 44. The minus terminal 28a and the soldering portion 4
The portion where 3 is exposed is covered and covered by applying silicone rubber as an insulating agent 45.

Further, as shown in FIG. 7, the periphery of the tip portion 37a of the conductive plate 37 is also insulated. In the connection between the tip 37a and the pattern of the printed circuit board 24, the copper foil surface 42 and the soldering portion 43 connect the metal surface to one side (the left side in FIG. 7) of the tip 37a. , The other side is a copper foil surface 4
Because there is no 2, there is no connection with the metal surface. Therefore, a portion inside the resist material 44 where the tip portion 37a and the soldering portion 43 are exposed is also covered by applying silicon rubber as the insulating agent 45.

As the insulating agent 45 used for these insulating processes, in addition to silicon rubber, for example, a coating agent such as a rubber-based resin or a fluororesin-based resin, or an insulating material such as a UV curable resin, a hot melt, a thermosetting resin, or a bond. High adhesives. In addition, as a method of coating these, brush coating, printing (silk, tampo), application such as dispensing of a constant amount with a dispenser, spray spraying, dip, and the like can be used.

Hereinafter, the operation of the present invention will be described. When performing flash photography using the film unit 2 with a lens, first, the operation button 10 for flash charging is slid and the flash charging switch 29 is turned on. Then, the current of the battery 41 is converted into an alternating current by the boosting circuit 56 and then boosted to around 300 V and applied to the main capacitor 28. When the main capacitor 28 is sufficiently charged, the LED incorporated in the strobe circuit is turned on, and the photographer recognizes that the charging is completed by checking the lighting through the light guide 14.

When the main capacitor 28 is fully charged as described above, the main capacitor 28 may be wet by water such as splash.
If water droplets are allowed to adhere to the lens-fitted film unit 2, an electrolyte solution such as seawater enters from the joint between the front cover 21 and the rear cover 22 and reaches the printed circuit board 24.

However, the portion having the same potential as the high voltage of about 300 V stored in the main capacitor 28, that is, the negative terminal 28a which is a high voltage portion and the metal surface and the soldering surface of the tip portion 37a of the conductive plate 37 are insulated. Since the insulation treatment by covering with the agent 45 is performed, even if an electrolyte solution such as seawater adheres to this portion,
Since there is no spark between the positive terminal 28b and the tip 38a of the contact piece 38, which are low-voltage parts in the vicinity, no electric short-circuit occurs and no explosive noise is generated.

In the above-described embodiment, only the high-voltage portion is subjected to the insulation treatment. However, as another embodiment of the present invention, the high-voltage portion is left exposed and the positive terminal 28b, which is the low-voltage portion, is exposed.
It is also possible to insulate only the tip 38a of the contact piece 38 by the same method, or to insulate both the high-voltage part and the low-voltage part by the same method. Even if it does, an electric short circuit between the high voltage part and the low voltage part can be prevented from occurring, so that an explosive sound does not occur.

Further, in the above-described embodiment, an example in which an insulating agent having an insulating property is applied to the exposed soldering surface and the metal surface as the insulating treatment has been described, but an adhesive tape having an insulating property is applied to the exposed portion. It is also possible to wear it and cover it up.

[0029]

As described above, according to the strobe device of the present invention, the conductive portion exposed on the printed circuit board is covered with the insulating material by performing soldering. Even if high voltage is generated in the state where it is attached, there is no spark between other conductive parts exposed around it, and malfunction or abnormal noise due to short circuit occurs There is no such thing.
Also, the terminals of the main capacitor and the conductive pieces directly connected to the strobe discharge tube are soldered in a state of protruding from the surface of the printed circuit board, and the potential difference from the surroundings is considerably large, so sparks are likely to occur. According to the present invention, it is possible to reliably prevent sparks from these locations.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a configuration of a strobe device.

FIG. 2 is an external perspective view of a film unit with lens embodying the present invention.

FIG. 3 is an exploded perspective view showing a configuration of a unit main body.

FIG. 4 is an exploded perspective view illustrating a configuration of a strobe light emitting unit.

FIG. 5 is an explanatory diagram illustrating a configuration of an insulation processing unit around a terminal of a main capacitor.

FIG. 6 is an explanatory diagram showing a configuration of an insulating portion around a front end portion of a conductive plate.

FIG. 7 is a circuit diagram illustrating an example of a strobe circuit.

[Explanation of symbols]

 2 Film unit with lens 3 Unit body 6 Shutter button 9 Shooting lens 10 Operation button 11 Strobe light emission window 14 Light guide 20 Strobe device 24 Printed circuit board 28 Main capacitor 29 Strobe charge switch 30 Sync switch 41 Power battery 42 Copper foil 43 Soldering Part 44 resist material 45 insulating material

Claims (3)

[Claims] An electronic component such as a strobe discharge tube and a main capacitor is mounted on a printed circuit board on which a predetermined circuit pattern is formed, and at least a part of the electrical component has connection terminals soldered to required portions of the circuit pattern. The strobe device according to claim 1, wherein a conductive portion exposed at a soldering portion between the connection terminal and the circuit pattern is covered with an insulating material. 2. The strobe device according to claim 1, wherein the conductive portion includes a solder surface provided between a connection terminal protruding from a surface of a printed circuit board and a required portion of a circuit pattern. 3. The connection terminal according to claim 1, wherein said connection terminal is connected to a terminal of a main capacitor or a terminal of a strobe discharge tube, and is connected to a circuit pattern of a printed circuit board.
The strobe device according to claim 1, wherein: