JP2001005070A - Short circuit preventing structure for discharge tube in flashing device and flashing device equipped with the structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a excellent short-circuit preventing structure for a discharge tube in a flashing device capable of preventing short-circuit discharge between a reflector and a main electrode by constituting a short-circuit discharge preventing means of a cylindrical body fit to the main electrode and covering all the periphery in the longitudinal direction of the main electrode exposed to the outside of the discharge tube in an electric insulating state. SOLUTION: The light emitting part of this flashing device 1 is provided with a cylindrical body 8 functioning as the short-circuit discharge preventing means fit to both of a main electrode 3 and the tube end 2a of the discharge tube 2 in the vicinity of the main electrode 3. The entire main electrode 3 and the tube end 2a are surely covered with a cylindrical body 8 with out leaving space nor easily moving through self-contraction action. By housing the discharge tube 2 in the core bottom part 7 of a reflector 6 so as to expose only the main electrode 3 to the outside so that the flash light of the device 1 may be effectively utilized, the short-circuit discharge between the reflector 6 and the main electrode 3 is surely prevented through the cylindrical body 8 even when the main electrode 3 of the discharge tube 2 and one part of the reflector 6 come close to each other to a distance where a high- voltage pulse easily flies.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for preventing a short circuit of a discharge tube in a flash device and a flash device having the structure, and more particularly to a flash device having a pair of main electrodes at the end of the tube. In a flash device in which a discharge tube having a trigger electrode on the tube peripheral surface is positioned at least inside the inside of a conductive reflector, a reflector that is generated when a high-voltage pulse is applied to the trigger electrode is used. The present invention relates to a structure for preventing a short circuit of a discharge tube in a flash device capable of preventing a short circuit discharge to a main electrode, and a flash device provided with the structure.

[0002]

2. Description of the Related Art Conventionally, a flash device has been disclosed in Japanese Utility Model Publication No. 53-30.
There is one equipped with a discharge tube having the structure described in Japanese Patent Publication No. 282.

That is, as shown in FIG. 4 (a), the discharge tube 2 described in the above publication has a pair of main and negative electrodes 3 made of a tungsten rod or the like on both sides of a tube end 2a. Is formed by applying a transparent conductive paint to form a trigger electrode 4, and between each electrode, a lead wire (not shown) is used for soldering a lead wire (not shown) to the main electrode 3. When the high-voltage pulse is applied to the trigger electrode 4, the high-voltage pulse jumps from the trigger electrode 4 to the main electrode 3 by flowing the solder to the root of the main electrode 3 and approaching the trigger electrode 4. Provided with a short-circuit prevention protection member 5 made of an insulating material having a through hole 5a for penetrating the main electrode 3 on both sides of the tube end in order to prevent the discharge tube 2 from flashing due to a short circuit caused by the It is.

Accordingly, in the flash device 1 having the discharge tube 2 having the above-described structure, as shown in FIG. 4 (b), at least the inner surface 6a is provided inside the core bottom portion 7 of the conductive reflector 6 having a conductive surface. Is stored.

[0005]

In the flash device 1 having the above structure, when the discharge tube 2 is positioned close to the core bottom surface 7a of the reflector 6, when a high voltage pulse is applied to the trigger electrode 4, Core bottom surface 7a of reflector 6 and trigger electrode 4
There is a potential potential to prevent short circuits due to high voltage pulse jumps between them, thereby preventing the adverse effects of such short circuits.

However, the reflector 6 is normally insulated from other members, so that no particular inconvenience arises. In recent years, for example, as shown in FIG. A structure has been proposed in which the entirety, that is, the main electrode 3 is housed in the core bottom 7 so as to expose only the main electrode 3 to the outside through a hole 7c formed in the wall surface 7b of the core bottom 7 of the reflecting umbrella 6, In the case of the proposal, the following disadvantages will occur.

That is, in the case of the above structure, FIG.
As shown in the figure, the space between the main electrode 3 of the discharge tube 2 and one portion of the reflector 6 is inevitably approached to a distance (arrow A) where the high-voltage pulse is likely to fly. There is a very serious problem that can be fatal to the flash device 1 in which a high-voltage pulse flies to the electrode 3.

However, the present invention provides a discharge tube which is housed in the bottom of the core of the reflector to expose only the main electrode to the outside so as to effectively utilize the flash, and the main electrode of the discharge tube and one part of the reflector are provided. An extremely excellent flash device that can reliably prevent short-circuit discharge between the reflector and the main electrode even when the high-voltage pulse approaches a distance where the high-voltage pulse can easily fly, and a discharge tube short-circuit prevention structure. It is an object of the present invention to provide a flash device having a prevention structure.

[0009]

SUMMARY OF THE INVENTION In order to solve this problem, the present invention provides a discharge tube having a pair of main and negative electrodes at the tube end and a trigger electrode on the circumferential surface of the tube. A short-circuit discharge preventing means for preventing short-circuit discharge between the main electrode and the reflective umbrella is provided on at least one of the reflectors in which the discharge tube is housed in the bottom of the core. The structure for preventing short-circuit of the discharge tube in the flash device and the means for preventing short-circuit discharge in the flash device having the structure for preventing short-circuit are provided by electrically insulating at least the entire circumference of the main electrode exposed to the outside of the discharge tube in the longitudinal direction. It is constituted by a tubular body that can be fitted onto the main electrode encapsulated in a state.

Accordingly, even if the main electrode of the discharge tube and one part of the reflector come close to a distance where the high voltage pulse can easily fly,
It is possible to obtain a short-circuit preventing structure for a discharge tube in a flash device capable of preventing a short-circuit discharge between a reflector and a main electrode, and a flash device having the structure.

[0011]

DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 of the present invention is directed to a discharge tube having a pair of main and negative electrodes at the tube end and a trigger electrode on the tube peripheral surface, wherein at least the inner surface is electrically conductive. A flash having a short-circuit discharge preventing means for preventing short-circuit discharge between the main electrode and the reflective umbrella on at least one of the umbrellas in which the discharge tube is housed in the bottom of the core. A short-circuit prevention structure for a discharge tube in an apparatus, wherein the short-circuit discharge prevention means covers the entire circumference of at least the main electrode exposed to the outside of the discharge tube in an electrically insulating state. The main electrode of the discharge tube and one part of the reflector come close to a distance where the high-voltage pulse can easily fly. It has the function of preventing short-circuit discharge.

According to a second aspect of the present invention, in the flash device according to the first aspect, the discharge tube in the structure for preventing short-circuiting of the discharge tube comprises a pair of main electrodes having a pair of Yin and Yang in a bottom of the core of the reflector. Are housed so as to be exposed to the outside, and have the same operation as the invention described in claim 1 above.

According to a third aspect of the present invention, in the flash device according to the first aspect, the tubular body in the short-circuit prevention structure of the discharge tube is constituted by a shrinkable tube. It has the same effect as the invention described in 1.

According to a fourth aspect of the present invention, there is provided a discharge tube having a pair of main and negative electrodes at a tube end and a trigger electrode on a tube peripheral surface, and at least an inner surface having conductivity. Discharge in a flash device provided with a short-circuit discharge prevention means for preventing short-circuit discharge between the main electrode and the reflector on at least one of the reflectors in which the discharge tube is accommodated in the bottom of the core. A flash device having a short-circuit prevention structure for a tube,
The short-circuit discharge preventing means comprises a tubular body that can be fitted onto the main electrode that covers at least the entire circumference of the main electrode exposed to the outside of the discharge tube in the longitudinal direction in an electrically insulated state. In addition, even when the main electrode of the discharge tube and one part of the reflector are close to a distance where the high voltage pulse can easily fly, there is an effect that a short-circuit discharge between the reflector and the main electrode can be prevented.

According to a fifth aspect of the present invention, in the flash device according to the fourth aspect of the present invention, the discharge tube in the structure for preventing short-circuit of the discharge tube comprises a pair of main electrodes having a pair of Yin and Yang inside a core bottom of the reflector. Are housed so as to be exposed to the outside, and have the same function as the invention according to the fourth aspect.

According to a sixth aspect of the present invention, in the flash device according to the fourth aspect, the cylindrical body in the short-circuit prevention structure of the discharge tube is constituted by a shrinkable tube. Has the same function as the invention described in (1).

According to a seventh aspect of the present invention, there is provided a discharge tube having a pair of main and negative electrodes at the tube end and a trigger electrode on the tube peripheral surface, at least an inner surface having conductivity, In a flash device, a short-circuit discharge preventing means for preventing a short-circuit discharge between the main electrode and the reflective umbrella is provided on at least one of the reflective umbrellas in which the discharge tube is housed in the bottom of the core. A short-circuit prevention structure for a discharge tube, wherein the short-circuit discharge prevention means is provided with a hole for exposing a tube end of the discharge tube or a main electrode of the discharge tube to the outside, provided on a core bottom wall portion of the reflector. The main electrode of the discharge tube and one part of the reflector come close to the distance where the high voltage pulse can fly easily even if the main electrode of the discharge tube and one part of the reflector come close to each other. Has the effect of preventing short-circuit discharge between electrodes

The invention according to claim 8 of the present invention provides a discharge tube having a pair of main electrodes at the tube end and a trigger electrode on the tube peripheral surface, wherein at least the inner surface has conductivity. Discharge in a flash device provided with a short-circuit discharge prevention means for preventing short-circuit discharge between the main electrode and the reflector on at least one of the reflectors in which the discharge tube is accommodated in the bottom of the core. A flash device having a short-circuit prevention structure for a tube,
The short-circuit discharge preventing means is made of an insulating paint or the like provided on a tube end of a discharge tube provided on a core bottom wall portion of the reflector or a region including a hole for exposing a main electrode of the discharge tube to the outside. It is equipped with a structure to prevent short circuit of the discharge tube in the flash device composed of special coating, and the main electrode of the discharge tube and one part of the reflector come close to the distance where the high voltage pulse can fly easily. This also has the effect that short-circuit discharge between the reflector and the main electrode can be prevented.

(Embodiment 1) FIG. 1 is a schematic side sectional view showing a main part of an embodiment of a flash unit provided with the structure for preventing short-circuit of a discharge tube in a flash unit according to the present invention. is there.

In FIG. 1, reference numeral 1 denotes a discharge tube 2 provided with a main electrode 3 and a trigger electrode 4, which is positioned and housed in a core bottom portion 7 of a conductive reflector 6 having at least an inner surface 6a. 2 shows a light emitting portion of a flash device having a configuration in which only a main electrode 3 protruding from 2 is exposed to the outside through a hole 7c formed in a wall surface 7b of the core bottom portion 7; By completely storing the flash, the flash of the flash device can be effectively used.

In the light emitting section 1 of the flash device, reference numeral 8 denotes a cylindrical body as short-circuit discharge preventing means for externally fitting both the main electrode 3 and the tube end 2a of the discharge tube 2 near the main electrode. ing.

The cylindrical body 8 is formed of a shrinkable tube formed of a material such as polyethylene and shrunk by heating, for example, and the entire main electrode 3 and the tube end 2a are closed without any gap through self-shrinkage. Enclose securely without moving easily. In addition, this encapsulation state will be firmly maintained.

Accordingly, one embodiment of the structure for preventing short-circuit of the discharge tube in the flash device shown in FIG. 1 and the flash device having the structure for preventing the short-circuit are as described above. The discharge tube 2 is housed in the core bottom 7 of the reflector 6 to expose only the main electrode 3 to the outside in order to effectively use the flash, so that the main electrode 3 and the reflector 6
(The inner peripheral edge of the hole 7c formed in the wall surface 7b)
However, even in the case of approaching a distance where the high-voltage pulse can easily fly, short-circuit discharge between the reflector 6 and the main electrode 3 can be reliably prevented via the tubular body 8.

(Embodiment 2) FIGS. 2 (a) and 2 (b)
FIG. 5 is a schematic side sectional view showing a main part of another embodiment of a flash device provided with the structure for preventing short circuit of a discharge tube in a flash device according to the present invention.

In the embodiment shown in FIG. 2 (a), the tubular body 8 as the short-circuit preventing means described in FIG. 1 has both the main electrode 3 and the tube end 2a of the discharge tube 2 near the main electrode. This is an example in which the cylindrical body 8A as a short-circuit preventing means is configured by a contraction tube that is externally fitted only to the main electrode 3 in contrast to the configuration in which the cylindrical body 8A is externally fitted. The reflection umbrella 6 and the main electrode 3 are provided by reliably realizing the insulation at the ends.
A short-circuit preventing structure for a discharge tube in a flash device capable of preventing short-circuit discharge between the flash device and the flash device having the structure.

The embodiment shown in FIG.
This is an example in which the main electrode 3 and the lead wire 10 connected to the main electrode 3 via the solder 9 are shaped so as to have an overall length capable of externally covering the entire connection portion with the main electrode 3. Accordingly, it is possible to obtain a structure for preventing a short circuit of the discharge tube in the flash device and a flash device provided with the prevention structure, which can more reliably prevent the short circuit discharge between the main electrode 3 and the reflector 6.

(Embodiment 3) FIGS. 3 (a) and 3 (b)
FIG. 7 is a schematic side sectional view showing a main part of a further embodiment of a flash device provided with a structure for preventing short-circuit of a discharge tube in a flash device according to the present invention.

In the embodiment shown in FIG. 3A, a short-circuit discharge preventing means is provided on the main electrode 3 described in FIG. 1 and on the tube end 2a of the discharge tube 2 near the main electrode 3. In addition to the body 8, the insulating bushings 11, 11 attachable to holes 7c provided in the wall surface 7b of the core bottom 7 of the reflector 6
This is an example in which A is added. In this case, a double short-circuit prevention structure is provided, so that short-circuit discharge between the main electrode 3 and the reflector 6 can be more reliably prevented. That is, similarly to the above embodiments, a short-circuit prevention structure of a discharge tube in a flash device capable of preventing a short-circuit discharge between the main electrode 3 and the reflector 6 and a flash device having the prevention structure are obtained. Can be.

The embodiment shown in FIG. 3 (b) is an example in which the short-circuit discharge preventing means is provided not in the discharge tube 2 but in the reflector 6 and the short-circuit discharge preventing means in this embodiment is provided. A part of the reflector 6 approaching the main electrode 3, that is, the wall surface of the core bottom 7 of the reflector 6 to expose the tube end 2a of the discharge tube 2 or the main electrode 3 of the discharge tube 2 to the outside. It is constituted by a special coating 12 made of an insulating paint or the like applied to an appropriate area including the hole 7c provided in the hole 7b.

Therefore, it is needless to say that short-circuit discharge between the main electrode 3 and the reflector 6 can be prevented.
In this embodiment, as in the previous embodiments, a short-circuit prevention structure for a discharge tube in a flash device capable of preventing short-circuit discharge between the main electrode 3 and the reflector 6 and a flash device having the prevention structure are obtained. be able to.

Although various embodiments have been described above,
The tubular body 8 formed of a shrinkable tube fitted to the main electrode 3 does not necessarily need to be a shrinkable tube. For example, the tubular body 8 may be formed of a simple insulating rubber or the like, whether soft or hard. good.

That is, the cylindrical member 8 described as an embodiment
Alternatively, it goes without saying that the specific material, shape, and the like of the short-circuit discharge preventing means, which is the special coating 12, are not limited to the examples illustrated and described.

Further, since the cylindrical body 8 in each of the above-described embodiments is made of a material having high transparency and is made substantially transparent, the use efficiency of flash light is reduced due to the portion covered by the cylindrical body 8. Can be prevented, which is more preferable.

[0034]

As described above, according to the present invention, the discharge tube is housed in the core bottom of the reflector to expose only the main electrode to the outside in order to effectively use the flash of the flash device. Even when the main electrode and one part of the reflector come close to a distance where the high-voltage pulse can easily fly, a flash device that can reliably prevent short-circuit discharge between the main electrode and the reflector. And a flash device provided with the structure for preventing short circuit of the discharge tube.

[Brief description of the drawings]

FIG. 1 is a schematic side sectional view showing a main part of an embodiment of a flash device provided with a structure for preventing short-circuit of a discharge tube in a flash device according to the present invention.

FIG. 2 (a) is a schematic side sectional view showing a main part of another embodiment of a flash device having a structure for preventing short circuit of a discharge tube in a flash device according to the present invention, and (b) the present invention. FIG. 2 is a schematic side sectional view showing a main part of a structure for preventing a short circuit of a discharge tube in a flash device and another embodiment of a flash device having the prevention structure.

FIG. 3 (a) is a schematic side sectional view showing a main part of a further embodiment of a flash device provided with a structure for preventing short-circuit of a discharge tube in a flash device according to the present invention, and (b) the present invention. FIG. 1 is a schematic side sectional view showing a structure for preventing a short circuit of a discharge tube in a flash device according to another embodiment of the present invention, and a main portion of still another embodiment of a flash device provided with the prevention structure.

FIG. 4 (a) is a schematic side sectional view showing the structure of a discharge tube disclosed in Japanese Utility Model Application Laid-Open No. 53-30282; FIG. 4 (b) shows an example of a flash device provided with the discharge tube shown in FIG. Schematic side sectional view

FIG. 5 is a schematic side sectional view showing an example of a flash device in a state where the discharge tube shown in FIG. 4 (a) is housed in a reflector so that only its main electrode is exposed to the outside;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Flash device 2 Discharge tube 3 Main electrode 4 Trigger electrode 5 Short circuit prevention protection member 6 Reflector 7 Core bottom 8 Cylindrical body (shrinkable tube) 9 Solder 10 Lead wire 11 Insulation bushing 12 Special coating

Claims (8)

[Claims] 1. A discharge tube having a pair of main electrodes at the tube end and a trigger electrode on the peripheral surface of the tube, and at least an inner surface having conductivity, the discharge tube being housed in the bottom of the core. A short-circuit prevention structure of a discharge tube in a flash device comprising a short-circuit discharge prevention means for preventing short-circuit discharge between the main electrode and the reflection umbrella on at least one of the reflection umbrellas, The short-circuit discharge prevention means is formed of a tubular body that can be fitted to the main electrode that covers at least the entire periphery of the main electrode exposed to the outside of the discharge tube in the longitudinal direction in an electrically insulated state. Structure to prevent short circuit of discharge tube in flash device. 2. A structure for preventing short-circuiting of a discharge tube in a flash device according to claim 1, wherein the discharge tube has only a pair of main electrodes exposed and exposed to the outside in the core bottom of the reflector. 3. The structure according to claim 1, wherein the tubular member is a shrinkable tube. 4. A discharge tube having a pair of main and negative electrodes at a tube end and a trigger electrode on a tube peripheral surface, wherein at least the inner surface has conductivity and the discharge tube is housed in the bottom of the core. A flash device provided with a short-circuit prevention structure for a discharge tube in a flash device provided with a short-circuit discharge prevention means for preventing short-circuit discharge between the main electrode and the reflection umbrella on at least one of the reflectors to be used. Wherein the short-circuit discharge preventing means comprises a cylindrical body which can be fitted to the main electrode which covers at least the entire circumference of the main electrode exposed to the outside of the discharge tube in an electrically insulating state. A flash device having a structure for preventing a short circuit of a discharge tube in a flash device having the above structure. 5. The flash device according to claim 4, wherein the discharge tube is accommodated in the core bottom of the reflector with only the pair of main electrodes exposed to the outside. 6. The flash device according to claim 4, wherein the tubular body is a contraction tube. 7. A discharge tube having a pair of main and negative electrodes at a tube end and a trigger electrode on a tube peripheral surface, and at least an inner surface having conductivity, wherein the discharge tube is housed in a core bottom portion. A short-circuit prevention structure of a discharge tube in a flash device comprising a short-circuit discharge prevention means for preventing short-circuit discharge between the main electrode and the reflection umbrella on at least one of the reflection umbrellas, The short-circuit discharge preventing means is formed of an insulating paint or the like applied to a tube end of a discharge tube provided on a core bottom wall portion of the reflector or a region including a hole for exposing a main electrode of the discharge tube to the outside. A structure to prevent short-circuiting of the discharge tube in a flash device composed of a special coating. 8. A discharge tube having a pair of main and negative electrodes at the tube end and a trigger electrode on the tube peripheral surface, at least the inner surface of which has conductivity, and the discharge tube being housed in the core bottom. A flash device provided with a short-circuit prevention structure for a discharge tube in a flash device provided with a short-circuit discharge prevention means for preventing short-circuit discharge between the main electrode and the reflection umbrella on at least one of the reflectors to be used. The short-circuit discharge preventing means is provided on a tube end of a discharge tube provided on a core bottom wall portion of the reflector or a region including a hole for exposing a main electrode of the discharge tube to the outside. A flash device equipped with a structure for preventing short-circuiting of a discharge tube in a flash device composed of a special coating of insulating paint or the like.