JP2001102148A - Discharging tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discharging tube of one directionality for allowing cost down. SOLUTION: A plurality of first discharge trigger lines 50 are centrally and transversely arranged erected inside a sealed tube 10 with their upper and lower ends respectively lying substantially in a second plane 33 containing the discharge plane 23 of the leading end of the upper discharge electrode and in a third plane 35 containing the discharge plane 25 of the leading end of the lower discharge electrode, or outside the second and third planes 33 and 35. The second discharge trigger lines 60 are arranged erected centrally between the first trigger lines 50 on the upper inside walls of the sealed tube 10 contacting the negative pole with their lower ends lying substantially in a fourth plane 37 centrally between the second plane 33 and the metallized surface 40 of the upper discharge electrode side, or between the fourth and third planes 37 and 33. The upper end of the second discharge trigger line 60 is connected to the metallized surface arranged in the upper end of the sealed tube 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge tube in which a discharge is repeatedly generated between a discharge surface at a tip of an upper discharge electrode and a discharge surface at a tip of a lower discharge electrode facing each other at the center in an airtight cylinder.

[0002]

2. Description of the Related Art JP-A-10-335 discloses a discharge tube used for a ballast circuit for lighting a HID (High Indenity Discharge) lamp of a vehicle, an igniter circuit for lighting a back lamp of a liquid crystal projector, and the like.
No. 042 is disclosed. This discharge tube is shown in FIG.
And the discharge surface 2 at the tip of the upper discharge electrode as shown in FIG.
A plurality of first discharge trigger lines 50 are erected vertically at a uniform pitch at the center of the inner wall of the hermetic cylinder 10 located around the discharge gap between the discharge gap 3 and the discharge surface 25 at the tip of the lower discharge electrode. They are formed side by side. At the center between the first discharge trigger lines 50 on the upper inner wall or the lower inner wall of the hermetic cylinder 10, a second discharge trigger line 60 is formed so as to stand up and down. The upper end or the lower end of the second discharge trigger line 60 is connected in series to the metallized surface 40 formed on the upper end surface or the lower end surface of the nearby hermetic cylinder 10.

In this discharge tube, the first discharge trigger line 50 and the second discharge trigger line 60 are formed at the center of the inner wall of the hermetic cylinder 10 and at the upper or lower inner wall. The first discharge trigger line 50 and the second discharge are generated by the sputter emitted from the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode and adhering to the central portion of the inner wall of the hermetic cylinder 10. It is possible to prevent the electrical insulation between the trigger line 60 from deteriorating. Then, the second discharge trigger line 60 and the first discharge trigger line 50
By using the above, a predetermined potential discharge can be repeatedly and stably generated between the discharge surface 23 of the upper discharge electrode tip and the discharge surface 25 of the lower discharge electrode tip over a long period of time.

This discharge tube has a first plane 31 (a plane shown by a chain line in FIG. 11) which crosses the center of the discharge gap between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode. Has an almost vertically symmetrical structure.
Then, each of the upper discharge electrode 22 and the lower discharge electrode 24 can be used for the positive electrode side and the negative electrode side, or conversely, can be used for the negative electrode side and the positive electrode side. That is, the discharge tube has a phase direction (bipolar). Then, a DC overvoltage can be applied between the upper discharge electrode 22 and the lower discharge electrode 24 in any direction.

[0005]

However, when the above-mentioned discharge tube is used for a DC circuit, as described above,
The discharge tube does not necessarily have to have a phase direction, and even if the discharge tube is unidirectional, it can sufficiently cope.

The unidirectional discharge tube does not need to form the second discharge trigger line 60 on the lower inner side wall of the hermetic cylinder 10 corresponding to the positive electrode side. The number of manufacturing steps can be reduced, and the cost can be reduced. Therefore, there has been a strong demand for the development of a low-cost unidirectional discharge tube for use in a DC circuit as described above.

In the above-mentioned ballast circuit or igniter circuit, the above-mentioned discharge tube is arranged close to the primary side booster coil of the circuit. Then, the winding direction of the primary side booster coil is the first discharge trigger line 50 of the discharge tube.
And a direction substantially perpendicular to the second discharge trigger line 60. Therefore, a current based on electromagnetic induction was generated in the first discharge trigger line 50 and the second discharge trigger line 60 under the influence of the magnetic field generated in the primary side booster coil. Then, under the influence of the current, the discharge surface 23 at the tip of the upper discharge electrode
The discharge potential repeatedly generated between the discharge electrode 25 and the discharge surface 25 at the tip of the lower discharge electrode fluctuates without stability, or the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode.
And the initial discharge start voltage generated between them increased.

The above-mentioned ballast circuit for lighting the HID lamp of the vehicle is fixed by being embedded in a resin such as urethane resin or epoxy resin in order to protect the circuit from impact or vibration. Then, the discharge tube is surrounded by the dielectric resin in which the ballast circuit is embedded.
Therefore, under the influence of the dielectric resin, a discharge is caused between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode on the second discharge trigger line 60 of the discharge tube. Electrons for creeping corona discharge for smooth induction cannot be efficiently converged.
Then, the initial discharge start voltage generated between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode has increased.

An object of the present invention is to provide a unidirectional discharge tube which can solve the above problems and can reduce the cost.

[0010]

In order to achieve the above-mentioned object, a discharge tube according to the present invention is characterized in that an upper end opening and a lower end opening of a hermetic cylinder made of an insulator are connected to an upper end surface and a lower part of the hermetic cylinder. A discharge tube hermetically sealed by an upper discharge electrode and a lower discharge electrode joined to each of the metallized surfaces formed on the end face, and a tip of an upper discharge electrode opposed at the center in the hermetic cylinder. A plurality of first discharge trigger lines are formed at the center of the inner wall of the hermetic cylinder located around the discharge gap between the discharge surface of the lower discharge electrode and the discharge surface of the tip of the lower discharge electrode. Positioned on the substantially same plane as the second plane including the discharge surface at the tip of the upper discharge electrode and the third plane including the discharge surface at the tip of the lower discharge electrode, or located outside the space between the second plane and the third plane. , Standing up and down, side by side, formed on the negative electrode side In the center of the upper inner wall of the hermetic cylinder between the first discharge trigger lines, a second discharge trigger line has a lower end crossing the center between the second plane and the metallized surface on the upper discharge electrode side. The upper surface of the second discharge trigger line is formed substantially vertically on the same plane as the four planes or between the fourth plane and the second plane. It is characterized by being connected to a surface.

In this discharge tube, a second discharge trigger line is connected in series to a metallized surface formed on the upper end surface of the hermetic cylinder, and the second discharge trigger line is connected to the upper discharge via the metallized surface. It is electrically connected to the electrodes. Therefore, the second discharge trigger line efficiently converges electrons for creeping corona discharge for smoothly inducing a discharge between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip. Can be. Then, by using the second discharge trigger line, a discharge of a predetermined potential can be repeatedly and stably generated between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip.

Also, no discharge trigger line is formed between the first discharge trigger line formed at the center of the inner wall of the hermetic cylinder and the metallized surface on the positive electrode side formed at the lower end surface of the hermetic cylinder. The inner wall portion of the airtight cylinder made of an insulator is widely interposed. For this purpose, spatters generated at the time of discharge from the discharge surface of the upper discharge electrode tip or the discharge surface of the lower discharge electrode tip are applied to the inner wall portion of the hermetic cylinder between the first discharge trigger line and the metallized surface on the positive electrode side. Even if it adheres, it is possible to prevent the electrical insulation between the first discharge trigger line and the metallized surface on the positive electrode side from deteriorating due to the sputtering.

In the manufacture, the second discharge trigger line may be formed only on the upper inner wall of the airtight cylinder, and it is not necessary to form the second discharge trigger line on the lower inner wall of the airtight cylinder. Therefore, the step of forming the second discharge trigger line can be reduced by almost half.

An aging process for activating the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode is performed between the upper discharge electrode on the negative electrode side and the lower discharge electrode on the positive electrode side. It can be performed only by applying a DC overvoltage in only one direction, and the troublesome aging process can be reduced by almost half. Here, the aging treatment is a process in which an overvoltage is repeatedly applied to the upper discharge electrode and the lower discharge electrode during the manufacture of the discharge tube, and a discharge is generated between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip. Is repeatedly and forcibly generated to activate the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode. By performing this process, a discharge can be smoothly and accurately generated between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip thereafter.

The upper end and the lower end of the first discharge trigger line formed at the center of the inner wall of the hermetic cylinder are respectively connected to the second plane including the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode. Is located on substantially the same plane as the third plane including or outside the space between the second plane and the third plane,
Since the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode are close to each other, the discharge surface of the tip of the upper discharge electrode and the discharge surface of the tip of the lower discharge electrode are determined using the first discharge trigger line. In the meantime, it is possible to repeatedly and stably generate a discharge of a predetermined potential.

The lower end of the second discharge trigger line formed on the upper inner wall of the hermetic cylinder is substantially the same as the fourth plane crossing the center between the second plane and the metallized surface on the upper discharge electrode side. The second discharge trigger line is too short because it is located on the surface or between the fourth plane and the second plane, and the second discharge trigger line is connected to the discharge surface at the tip of the upper discharge electrode and the lower surface. It is possible to prevent electrons for creeping corona discharge from being unable to efficiently converge to smoothly induce discharge between the discharge surface and the discharge surface at the tip of the discharge electrode. And
Due to the second discharge trigger line, it becomes impossible to repeatedly and stably generate a discharge of a predetermined potential between the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode. It is possible to prevent the initial discharge starting voltage generated between the surface and the discharge surface at the tip of the lower discharge electrode from rising. In addition, the second discharge trigger line is too long, and the second discharge trigger line is too close to the first discharge trigger line, so that the discharge surface at the tip of the upper discharge electrode or the discharge surface at the tip of the lower discharge electrode discharges. The electric insulation between the first discharge trigger line and the second discharge trigger line can be prevented from deteriorating due to the spatter generated at the time of the above and attached to the center portion of the inner wall of the airtight cylinder.
Then, by using the second discharge trigger line, a predetermined potential can be repeatedly and stably generated between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip over a long period of time. It can be prevented from running out.

In the discharge tube according to the present invention, it is preferable that the second discharge trigger line has a structure in which a lower end thereof is located substantially on the same plane as the fourth plane.

In this discharge tube, the second discharge trigger line is too long, so that it is greatly affected by the magnetic field of the primary side booster coil, and a large current is generated in the second discharge trigger line. Can be prevented. Then, under the influence of the current, a discharge potential repeatedly generated between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip or the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip Can be prevented from fluctuating in the initial discharge start potential generated between the first and second discharge start potentials. In addition, it is difficult to efficiently converge the surface discharge corona discharge electrons on the second discharge trigger line because the second discharge trigger line is too short.
Can be prevented. Due to the second discharge trigger line, it becomes impossible to repeatedly and stably generate a discharge of a predetermined potential between the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode. It can be prevented that the discharge starting voltage generated for the first time between the discharge surface and the discharge surface at the tip of the lower discharge electrode rises.

Further, in the discharge tube according to the present invention, the first discharge trigger line and the second discharge trigger line are formed so as to be inclined in the same direction with respect to the axial direction of the airtight cylinder. It is preferred.

In this discharge tube, the first discharge trigger line and the second discharge trigger line are formed so as to be inclined in the same direction with respect to the axial direction of the airtight cylinder. The second discharge trigger line is directed obliquely up and down close to the winding direction of the primary side booster coil. for that reason,
It is possible to prevent a current from being generated in the first discharge trigger line and the second discharge trigger line under the influence of the magnetic field of the primary side booster coil. In addition, it is possible to prevent the discharge potential repeatedly induced between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip from fluctuating under the influence of the current. At the same time, even if the discharge tube is surrounded by the resin made of the above-described dielectric, the second discharge trigger line facing obliquely upward and downward is provided between the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode. In this case, electrons for creeping corona discharge can be efficiently converged in order to induce discharge smoothly. Then, using the second discharge trigger line,
Discharge of a predetermined potential can be repeatedly and stably generated between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip. Further, since the first discharge trigger line and the second discharge trigger line are formed to be inclined in the same direction, the distance between the first discharge trigger line and the second discharge trigger line can be kept uniform. it can. Then, by using the discharge trigger line and the second discharge trigger line, a discharge of a predetermined potential can be repeatedly and stably generated between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip. .

Further, in the discharge tube of the present invention, it is preferable that the second discharge trigger line is composed of a plurality of second sub-discharge trigger lines that are closely arranged.

In this discharge tube, when a discharge is repeatedly generated between the discharge surface at the tip of the discharge electrode of the discharge tube and the discharge surface at the tip of the lower discharge electrode, the discharge surface at the tip of the upper discharge electrode The initial discharge start voltage generated between the first discharge electrode and the discharge surface at the tip of the lower discharge electrode can be stabilized at a constant voltage over a long period of time. This is particularly true when the discharge tube is placed in a dark place and the discharge surfaces at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode in a gas in which the electrons in the space inside the hermetic cylinder of the discharge tube are not excited. This is remarkable when a discharge is repeatedly generated between the discharge lamps. In this case, the initial discharge starting voltage can be kept constant, and the life of the discharge tube can be greatly extended.

The reason is that, in the case of the second discharge trigger line composed of one wire, the discharge is repeatedly generated between the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode of the discharge tube. In addition, a second layer made of carbon or the like formed on the inner wall of the airtight cylinder near the discharge surface under the influence of the discharge
This is because the tip of the discharge trigger wire becomes spatter and scatters in the airtight cylinder space, and gradually disappears early.
And the tip of the second discharge trigger line consisting of the one,
This is because the distance between the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode, which is located nearer, gradually increases. As a result, when a discharge is generated between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip using the second discharge trigger line made up of one piece whose tip is lost and shortened. This is because the initial discharge starting voltage gradually increases early.

On the other hand, when the second discharge trigger line is composed of a plurality of second sub-discharge trigger lines arranged close to each other, the discharge surface at the tip of the upper discharge electrode and the tip of the lower discharge electrode of the discharge tube. A plurality of second sub-discharge triggers made of carbon or the like formed on the inner wall of the hermetic cylinder near the discharge surface under the influence of the discharge when the discharge is repeatedly generated between the discharge subsurface and the discharge surface. Even if the tip of the second sub-discharge trigger line of a part of the second discharge trigger line in which the lines are closely arranged becomes spatter and scatters into the airtight cylinder space and disappears,
This is because the other end of the second discharge trigger line does not disappear and continues to remain in a long state. Therefore, the tip of one or more second sub-discharge trigger lines that continue to remain in the long state of the second discharge trigger line, and the discharge surface of the tip of the upper discharge electrode or the tip of the lower discharge electrode arranged near the tip This is because the distance from the surface may not be large. As a result, by using one or more second sub-discharge trigger lines, the tips of which are left in a long state without being lost, the discharge surface at the tip of the upper discharge electrode, the lower discharge surface, and the discharge surface at the electrode tip are used. This is because, when it is repeatedly generated, the initial discharge start voltage can be kept constant without gradually increasing the voltage at the early stage.

When the plurality of second sub-discharge trigger lines constituting the second discharge trigger line are too close to each other,
The plurality of second sub-discharge trigger lines have the same function as the single second discharge trigger line, and the plurality of second sub-discharge trigger lines arranged too close to each other It has been experimentally confirmed that the first discharge start voltage of the discharge tube in a dark place or the like gradually increases early using the second discharge trigger line composed of. Further, even if the plurality of second sub-discharge trigger lines constituting the second discharge trigger line are too far apart from each other, each of the plurality of second sub-discharge trigger lines is opposite to the second It has the same function as the discharge trigger line, and using the second discharge trigger line composed of a plurality of second sub-discharge trigger lines arranged too far apart from each other makes it possible to use a discharge tube in a dark place or the like. It has been confirmed by experiments that the initial discharge start voltage gradually increases early. That is, the distance between the plurality of second sub-discharge trigger lines constituting the second discharge trigger line is adjusted according to the value of the initial discharge start voltage or the diameter of the hermetic cylinder. The need has been confirmed by experiments.

[0026]

1 and 2 show a preferred embodiment of a discharge tube according to the present invention. FIG. 1 is a front sectional view of the discharge tube, and FIG. 2 is a developed view of an inner wall of the airtight cylinder. Hereinafter, this discharge tube will be described.

In FIG. 1, reference numeral 10 denotes a cylindrical airtight cylinder made of an insulator such as ceramic. Each of the upper end opening and the lower end opening of the hermetic cylinder 10 is covered with an upper discharge electrode 22 and a lower discharge electrode 24 made of a metal such as a 42 alloy (iron-nickel alloy). In particular,
The outer ends of the upper discharge electrode 22 and the lower discharge electrode 24 are formed on disk-shaped lids 26 and 28, and the lid 2
The upper end opening and the lower end opening of the airtight cylinder 10 are covered by 6, 28.

Each of the upper discharge electrode 22 and the lower discharge electrode 24 is air-tightly brazed to a metallized surface 40 made of chromium or the like formed on the upper end surface and the lower end surface of the airtight cylinder 10. The inner space of the hermetic cylinder 10 in which a mixed gas such as an inert gas is sealed is hermetically sealed by the upper discharge electrode 22 and the lower discharge electrode 24.

The tip of the upper discharge electrode 22 and the tip of the lower discharge electrode 24 housed in the inner part of the airtight cylinder 10 are formed in a small-diameter cylindrical shape, and the tip of the upper discharge electrode 22 and the tip of the lower discharge electrode 24 are connected to each other. , Are arranged facing each other at the center in the airtight cylinder 10. The discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode have these discharge surfaces 2
A recess 27 is provided between 3 and 25 for stably generating a discharge.

The above arrangement is the same as that of the conventional discharge tube. However, in the discharge tube shown in the figure, the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode which face each other at the center in the hermetic cylinder 10. Hermetic cylinder 1 located around the discharge gap between
As shown in FIG. 2, a plurality of first discharge trigger lines 50 made of carbon or the like having a line width of about 0.5 mm are arranged vertically at equal intervals at the center of the inner wall of the inner wall 0. They are formed side by side. The first discharge trigger line 50 has an upper end and a lower end each of which is a second plane (a surface indicated by a chain line in FIG. 1) 33 including the discharge surface 23 at the tip of the upper discharge electrode.
And a third plane including the discharge surface 25 at the tip of the lower discharge electrode (FIG. 1)
(A surface indicated by a dashed-dotted line in FIG. 3) 35 or on the outer side of the space between the second plane 33 and the third plane 35, and is formed upright.

In the center between the first discharge trigger lines 50 on the upper inner wall of the airtight cylinder 10 corresponding to the negative electrode side, the line width is about 0.5.
A second discharge trigger line 60 made of carbon or the like of mm is formed upright. Second discharge trigger line 60
Is a fourth plane which crosses the lower end thereof at the center between the second plane 33 including the discharge surface 23 at the tip of the upper discharge electrode and the metallized surface 40 on the upper discharge electrode 22 side (the plane indicated by a chain line in FIG. 1). 37 or a fourth plane 37 and a second plane 37
It is formed between the flat surface 33 and upright.

The upper end of the second discharge trigger line 60 is connected in series to a metallized surface 40 formed on the upper end surface of the hermetic cylinder 10 near it.

The second inner wall of the hermetic cylinder 10 made of an insulator is widely exposed without forming the second discharge trigger line 60 on the lower inner wall of the hermetic cylinder 10 corresponding to the positive electrode side.

The discharge tube shown in FIGS. 1 and 2 is configured as described above.

FIG. 3 shows another preferred embodiment of the discharge tube of the present invention, and FIG. 3 is a developed view of the inner wall of the hermetic cylinder. Hereinafter, this discharge tube will be described.

In this discharge tube, the first discharge trigger line 50
And the second discharge trigger line 60 are formed in the central portion of the inner wall and the upper inner wall of the hermetic cylinder 10 inclining in the same direction with respect to the axial direction of the hermetic cylinder 10.

In other respects, the structure is the same as that of the first discharge tube shown in FIGS.

In the discharge tube shown in FIG. 1, FIG. 2 or FIG. 3, the second discharge trigger line 60 is
Is electrically connected to the upper discharge electrode 22 through the second discharge trigger line 60, the discharge is smoothly performed between the discharge surface 23 of the upper discharge electrode tip and the discharge surface 25 of the lower discharge electrode tip. The electrons for creeping corona discharge for inducing convergence can be efficiently converged. And the second
By using the discharge trigger line 60, a discharge of a predetermined potential can be repeatedly and stably generated between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode.

Since the inner wall portion of the hermetic cylinder 10 made of an insulator on which no discharge trigger line is formed is widely interposed between the first discharge trigger line 50 and the metallized surface 40 on the positive electrode side, Spatters generated at the time of discharge from the discharge surface 23 at the top of the upper discharge electrode or the discharge surface 25 at the bottom of the lower discharge electrode cause the airtight cylinder 10 between the first discharge trigger line 50 and the metallized surface 40 on the positive electrode side. Even if it adheres to the inner wall portion, it is possible to prevent the electrical insulation between the first discharge trigger line 50 and the metallized surface 40 on the positive electrode side from being deteriorated by the sputtering. Then, a discharge of a predetermined potential can be repeatedly and stably generated between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode for a long period of time.

In the manufacture, the second discharge trigger line 60 may be formed only on the upper inner wall of the hermetic cylinder 10, and the second discharge trigger line 60 may be formed on the lower inner wall of the hermetic cylinder 10. Therefore, the step of forming the second discharge trigger line 60 can be substantially halved.

The aging process for activating the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode is performed on the upper discharge electrode 22 on the negative electrode side and the lower discharge electrode 24 on the positive electrode side. Can be performed only by applying a DC overvoltage in only one direction, and the troublesome aging process can be reduced to almost half.

The upper and lower ends of the first discharge trigger line 50 are respectively formed by a second plane 33 including the discharge surface 23 at the tip of the upper discharge electrode and a third plane 35 including the discharge surface 25 at the tip of the lower discharge electrode. The first discharge trigger line 50 is located on substantially the same plane or outside the space between the second plane 33 and the third plane 35, and the first discharge trigger line 50 is connected to the discharge surface 23 at the tip of the upper discharge electrode and to the tip of the lower discharge electrode. Since the first discharge trigger line 50 is used, the discharge of the predetermined potential is repeated between the discharge surface 23 at the top of the upper discharge electrode and the discharge surface 25 at the top of the lower discharge electrode. Can be generated.

Further, the lower end of the second discharge trigger line 60 is substantially flush with the fourth plane 37 crossing the center between the second plane 33 and the metallized surface 40 on the upper discharge electrode 22 side, or on the same plane. Since the second discharge trigger line 60 is located between the fourth plane 37 and the second plane 33 and is sufficiently long without being too short, the second discharge trigger line 60 is provided with the discharge surface 23 at the tip of the upper discharge electrode. Electrons for creeping corona discharge can be efficiently converged to smoothly induce a discharge between the discharge electrode 25 and the discharge surface 25 at the tip of the lower discharge electrode. Then, by the second discharge trigger line 60, a discharge of a predetermined potential is repeatedly and stably generated between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode. It is possible to prevent the initial discharge start voltage generated between the discharge surface 23 and the discharge surface 25 at the tip of the lower discharge electrode from rising. Also, the second discharge trigger line 60 is too long, and the second discharge trigger line 60 is
Is too close to the inner surface of the hermetic cylinder 10 due to the spatter emitted from the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode and attached to the center of the inner wall of the hermetic cylinder 10. It is possible to prevent the electrical insulation between the discharge trigger line 60 and the first discharge trigger line 50 from deteriorating. Then, the first discharge trigger line 50 and the second discharge trigger line 60 cause discharge of a predetermined potential between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode for a long time. It is possible to prevent a situation in which it is not possible to stabilize and generate repeatedly.

In the discharge tube shown in FIG. 1, FIG. 2 or FIG. 3, the lower end of the second discharge trigger line 60 is connected to the fourth discharge trigger line 60.
It may be formed so as to be located on substantially the same plane as the plane 37. In this case, since the second discharge trigger line 60 is too long, it is greatly affected by the magnetic field of the primary side booster coil, thereby preventing a large current from being generated in the second discharge trigger line 60. Can be. Then, it is possible to prevent the discharge potential repeatedly generated between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode from fluctuating under the influence of the current. In addition, it is possible to prevent the second discharge trigger line 60 from being too short and preventing the surface discharge corona discharge electrons from being efficiently converged on the second discharge trigger line 60. Due to the second discharge trigger line 60, it becomes impossible to repeatedly and stably generate a discharge of a predetermined potential between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode. It is possible to prevent an increase in the initial firing voltage generated between the discharge surface 23 at the tip of the discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode.

In the discharge tube shown in FIG. 3, the first discharge trigger line 50 and the second discharge trigger line 60 are formed to be inclined in the same direction with respect to the axial direction of the hermetic cylinder 10. Since the first discharge trigger line 50 and the second discharge trigger line 60 face diagonally up and down close to the winding direction of the primary booster coil, the first discharge trigger line 50 and the second discharge trigger wire 60 are affected by the magnetic field of the primary booster coil. Thus, it is possible to prevent current from being generated in the first discharge trigger line 50 and the second discharge trigger line 60. Then, it is possible to prevent the discharge potential repeatedly generated between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode from fluctuating under the influence of the current. At the same time, even if the discharge tube is surrounded by the above-mentioned resin made of a dielectric material, the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode are attached to the second discharge trigger line 60 which faces obliquely up and down. The electrons for the creeping corona discharge for smoothly inducing the discharge can be efficiently converged. Then, the second discharge trigger line 6
By using 0, a discharge of a predetermined potential can be repeatedly and stably generated between the discharge surface 23 of the upper discharge electrode tip and the discharge surface 25 of the lower discharge electrode tip. Further, since the first discharge trigger line 50 and the second discharge trigger line 60 are formed to be inclined in the same direction, the distance between the first discharge trigger line 50 and the second discharge trigger line 60 is made uniform. Can be kept constant. Then, the first discharge trigger line 5
Using 0 and the second discharge trigger line 60, a discharge of a predetermined potential can be repeatedly and stably generated between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode.

FIG. 4 or FIG. 5 shows another preferred embodiment of the discharge tube of the present invention, and FIG. 4 or 5 is a developed view of the inner wall of the hermetic cylinder. Hereinafter, this discharge tube will be described.

In the discharge tube shown in FIG. 4 or FIG. 5, the second discharge trigger line 60 has a plurality of (three in FIG. 4, and two in FIG. 5) second sub-discharge trigger lines 62 approaching and substantially parallel to each other. It is composed of things arranged in a row.

The other components are the same as those of the above-described discharge tube shown in FIG. 1, FIG. 2 or FIG. In this discharge tube, when a discharge is repeatedly generated between the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 25 at the tip of the lower discharge electrode, the tip of the upper discharge electrode of the discharge tube The initial discharge start voltage generated between the discharge surface 23 and the discharge surface 25 at the tip of the lower discharge electrode can be stabilized at a constant voltage for a long period of time. This is particularly true when the discharge tube is placed in a dark place, and the discharge surface 23 at the tip of the upper discharge electrode and the discharge surface 23 at the tip of the lower discharge electrode in a gas in which the electrons in the space inside the hermetic cylinder 10 of the discharge tube are not excited. This is remarkable when a discharge is repeatedly generated between the discharge surface 25 and the first discharge start voltage at that time, and the life of the discharge tube can be greatly extended.

The reason is as described in the paragraph numbers 0023 and 0024 described above.

FIG. 6 shows that four first discharge trigger lines 50 are formed at the center of the inner side wall of the hermetic cylinder 10 so as to be erected vertically and arranged side by side at equal intervals. In the center between each of the four first discharge trigger lines 50, an operating voltage as shown in FIG.
4 shows the results of a life test of a 0 V discharge tube in a dark place. On the other hand, FIG. 7 shows that four first discharge trigger lines 50 are formed at the center of the inner side wall of the hermetic cylinder 10 so as to stand up and down and are arranged side by side at equal intervals. At the center between the four first discharge trigger lines 50 on the wall, a second discharge trigger line 6 in which two second sub-discharge trigger lines 62 are arranged in close proximity to each other is formed up and down. 9 shows a life test result of a discharge tube having an operating voltage of 1000 V in a dark place. FIG. 8 shows that four first discharge trigger lines 50 are formed at the center of the inner side wall of the hermetic cylinder 10 so as to stand up and down and are arranged side by side at equal intervals.
The second discharge trigger line 6 in which the three second sub-discharge trigger lines 62 are closely arranged in the center between each of the four first discharge trigger lines 50 on the upper inner wall of the upper part 0 rises up and down. 5 shows the results of a life test in a dark place of a discharge tube having an operating voltage of 1000 V formed as shown in FIG.

FIG. 9 shows that four first discharge trigger lines 50 are formed at the center of the inner wall of the hermetic cylinder 10 so as to stand up and down and are arranged side by side at equal intervals. In the center between each of the four first discharge trigger lines 50, an operating voltage as shown in FIG.
12 shows the results of a life test of a V discharge tube in a dark place.
On the other hand, FIG.
The first discharge trigger lines 50 are formed side by side at equal intervals so as to stand up and down, and the center between each of the four first discharge trigger lines 50 on the upper inner wall of the hermetic cylinder 50. In addition, the second discharge trigger line 6 in which three second sub-discharge trigger lines 62 are arranged close to each other is formed up and down, and the dark place of a discharge tube having an operating voltage of 800 V as shown in FIG. 3 shows the results of a life test in Example 1.

According to these experimental results, a plurality of second
In the discharge tube shown in FIG. 6 or FIG. 9 in which a single second discharge trigger line 60 having no sub-discharge trigger line 62 is formed on the upper inner wall of the hermetic cylinder 10, the cumulative number of discharges is When it reaches about 15,000 times or about 50,000 times or more, the initial discharge starting voltage becomes 1200 V, which is the usage limit.
Or it turns out that it exceeds 1000V. On the other hand, the second discharge trigger line 60 in which two or three second sub-discharge trigger lines 62 are arranged close to each other is shown in FIG. Discharge tube, the cumulative number of discharges is about 50,000 times,
It can be seen that up to 1,500,000 times or more, or 200,000 times or more, the initial discharge starting voltage does not exceed the usage limit of 1200 V or 1000 V, and the life is greatly extended.

The outer diameter of the airtight tube 10 of the discharge tube used to obtain the experimental data shown in FIGS. 6 to 10 was about 8 mm. The distance between adjacent side edges of the second sub-discharge trigger line 62 constituting the second discharge trigger line 60 shown in FIG. 7, 8 or 10 is 0.2 mm. In the discharge tube shown in FIG. 7, FIG. 8 or FIG. 10 used for obtaining these experimental data, the distance between the adjacent side edges of the second sub-discharge trigger line 62 is 0.1 to 0.25 mm. Experiments have confirmed that it is good to open. That is, the adjacent second
If the distance between the side edges of the sub-discharge trigger line 62 is reduced to less than 0.1 mm, the two or three second sub-discharge trigger lines 6
The second discharge trigger line 60 composed of two
The discharge trigger line 60 has the same function as that of the discharge trigger line 60. In this case, the first discharge start voltage in a dark place or the like of the discharge tube rises early. The distance between the side edges of the adjacent second sub-discharge trigger lines 62 is 0.25 mm.
More broadly, each of the two or three second discharge trigger lines 60 composed of the second sub-discharge trigger lines 62 has the same function as the second discharge trigger line 60 composed of one. In this case as well, the initial discharge starting voltage in a dark place or the like of the discharge tube quickly rises.

[0054]

As described above, according to the discharge tube of the present invention, the second discharge trigger line needs to be formed only on the upper inner wall of the hermetic cylinder, and the lower inner wall of the hermetic cylinder has Since it is not necessary to form the second discharge trigger line, the step of forming the second discharge trigger line can be reduced by almost half, and the cost can be significantly reduced.

Further, the first discharge trigger line and the second discharge trigger line are provided for smoothly inducing a discharge between the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode.
Electrons for creeping corona discharge can be efficiently converged. Then, using the first discharge trigger line and the second discharge trigger line, a discharge of a predetermined potential is repeatedly and stably generated between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip. In addition, it is possible to keep the discharge starting voltage generated initially between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip constant.

An aging process for activating the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode is performed between the upper discharge electrode on the negative electrode side and the lower discharge electrode on the positive electrode side. It can be performed only by applying a DC overvoltage in only one direction, and the troublesome aging process can be reduced by almost half.

The inner wall portion of the airtight cylinder made of an insulator without a discharge trigger line is widely interposed between the positive electrode side metallized surface formed on the lower end surface of the airtight cylinder and the first discharge trigger line. Therefore, even if spatter generated at the time of discharge from the discharge surface of the upper discharge electrode tip or the discharge surface of the lower discharge electrode tip adheres to the inner wall portion of the hermetic cylinder, the metallized surface on the positive electrode side due to the spatter It is possible to prevent the electrical insulation between the first and second discharge trigger lines from deteriorating. Then, a discharge of a predetermined potential can be repeatedly and stably generated between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip over a long period of time.

In a discharge tube in which the first discharge trigger line and the second discharge trigger line are inclined in the same direction with respect to the axial direction of the hermetic cylinder, a primary boosting coil such as a ballast circuit is provided. A large current can be prevented from being generated in the first discharge trigger line and the second discharge trigger line due to the influence of the magnetic field. Then, it is possible to prevent the discharge potential repeatedly generated between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip from fluctuating under the influence of the current. At the same time, even if the discharge tube is embedded in the resin of the dielectric, under the influence of the resin, the discharge tube between the discharge surface at the tip of the upper discharge electrode and the discharge surface at the tip of the lower discharge electrode is affected by the second discharge trigger line. It is possible to prevent the electrons for creeping corona discharge for smoothly inducing the discharge from being efficiently converged. Then, it is possible to prevent an increase in the discharge starting voltage generated initially between the discharge surface of the upper discharge electrode tip and the discharge surface of the lower discharge electrode tip. Furthermore, the distance between the first discharge trigger line and the second discharge trigger line is kept uniform, and the first discharge trigger line and the second discharge trigger line allow the discharge surface at the tip of the upper discharge electrode and the lower discharge trigger line. Discharge of a predetermined potential can be repeatedly and stably generated between the discharge surface of the electrode tip and the discharge surface.

In a discharge tube in which the second discharge trigger line is composed of a plurality of second sub-discharge trigger lines arranged close to each other, the first discharge start voltage in a dark place or the like of the discharge tube is set to a long term. Over a period of time, it is possible to keep the voltage below a certain value. Then, the life of the discharge tube can be greatly extended.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a discharge tube of the present invention.

FIG. 2 is a developed view of an inner wall of an airtight cylinder of the discharge tube according to the present invention.

FIG. 3 is a development view of the inner wall of the hermetic cylinder of the discharge tube of the present invention.

FIG. 4 is a development view of the inner wall of the airtight cylinder of the discharge tube of the present invention.

FIG. 5 is a development view of the inner wall of the hermetic cylinder of the discharge tube of the present invention.

FIG. 6 is a data diagram of a life test result of the discharge tube of the present invention in a dark place.

FIG. 7 is a data diagram of a life test result of the discharge tube of the present invention in a dark place.

FIG. 8 is a data diagram of a life test result of the discharge tube of the present invention in a dark place.

FIG. 9 is a data diagram of a life test result of a discharge tube of the present invention in a dark place.

FIG. 10 is a data diagram of a life test result of the discharge tube of the present invention in a dark place.

FIG. 11 is a front sectional view of a conventional discharge tube.

FIG. 12 is a development view of an inner wall of a hermetic cylinder of a conventional discharge tube.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Hermetic cylinder 22 Upper discharge electrode 23 Discharge surface at the tip of upper discharge electrode 24 Lower discharge electrode 25 Discharge surface at the tip of lower discharge electrode 26, 28 Lid 33 Second plane 35 Third plane 37 Fourth plane 40 Metallized plane 50 First Discharge trigger line 60 Second discharge trigger line 62 Second sub-discharge trigger line

Claims (4)

[Claims] 1. An upper discharge electrode and a lower discharge electrode, wherein an upper end opening and a lower end opening of an airtight cylinder made of an insulator are respectively joined to metallized surfaces formed on an upper end surface and a lower end surface of the airtight cylinder. A discharge tube, which is hermetically sealed by electrodes, around a discharge gap between a discharge surface of a tip of an upper discharge electrode and a discharge surface of a tip of a lower discharge electrode opposed at the center in the hermetic cylinder. A plurality of first discharge trigger lines are respectively formed at the center of the inner wall of the hermetic cylinder located at the upper end and the lower end of the first discharge trigger line, the second plane including the discharge surface of the upper discharge electrode tip, and the discharge surface of the lower discharge electrode tip. Is located on substantially the same plane as the third plane including or outside the space between the second plane and the third plane,
A second discharge trigger line is formed at the center between the first discharge trigger lines on the upper inner wall of the hermetic cylinder corresponding to the negative electrode side. It is positioned substantially on the same plane as a fourth plane crossing the center between the second plane and the metallized surface on the upper discharge electrode side or between the fourth plane and the second plane, and is vertically raised. A discharge tube, wherein an upper end of the second discharge trigger line is connected to the metallized surface near the second discharge trigger line. 2. The discharge tube according to claim 1, wherein said second discharge trigger line is formed with its lower end located substantially on the same plane as said fourth plane. 3. The discharge tube according to claim 1, wherein the first discharge trigger line and the second discharge trigger line are formed to be inclined in the same direction with respect to the axial direction of the airtight cylinder. 4. The discharge tube according to claim 1, wherein the second discharge trigger line comprises a plurality of second sub-discharge trigger lines arranged closely.