KR102580368B1 - Discharge lamp, and method for producing discharge lamp - Google Patents

Abstract

[Assignment] Encapsulate the mount parts of short arc type discharge lamps, etc. to prevent wrinkles from forming in the metal foil. [Solution] A plurality of metal foils 36 are disposed on the outer surface of the pillar-shaped glass member 34 along the lamp axis direction, and the outer peripheral surface 26S of the inner metal ring 26 connected to the electrode support rod 22 is formed. In the discharge lamp 10 in which the metal foil 36 is welded to the inner metal ring, the annular pressure-welded member 50 is on and near the outer peripheral surface 26S of the inner metal ring 26, and attaches the metal foil 36 to the inner metal ring. It is pressed toward the center of the (glass member) and tightened tightly.

Description

Discharge lamp and method of manufacturing the discharge lamp {DISCHARGE LAMP, AND METHOD FOR PRODUCING DISCHARGE LAMP}

The present invention relates to discharge lamps such as short arc type discharge lamps, and particularly to the encapsulation structure of the discharge lamp.

In a short arc type discharge lamp or the like, a glass sealing tube is formed integrally at both ends of the light emitting tube that seals the electrode, and the mount part is enclosed within the sealing tube. In the mounted part, the electrode support rod is inserted into a cylindrical glass tube and held by the glass tube. Additionally, metal foil is disposed along the surface of the pillar-shaped glass member (glass rod), and power is supplied to the electrode side through the metal foil. In a discharge lamp with high power, an annular member such as a metal ring is fixed to an electrode support rod, and a plurality of metal foils are welded to the outer peripheral surface of the annular member (see Patent Document 1).

Patent Document 1: Japanese Patent Publication No. 2009-238671

Metal foil is hard and difficult to bend in the width direction. Therefore, when the metal foil is welded to the annular member, the vicinity of both edges of the foil along the axial direction does not follow the outer surface of the glass member, but floats away from the surface. When the mount component is sealed in this state, that is, when the glass sealing tube and the glass member are welded, wrinkles and loosening occur in the metal foil. These wrinkles and lifting may cause cracks to occur in the sealing portion.

Therefore, it is required to encapsulate the mount components to prevent wrinkles, etc. from forming in the metal foil in short arc type discharge lamps, etc.

The discharge lamp of the present invention includes a pillar-shaped glass member installed in a sealing tube formed integrally with the light emitting tube and welded to the sealing tube, a plurality of metal foils extending in the lamp axis direction between the sealing tube and the glass member, and a plurality of metal foils. A conductive ring-shaped member that contacts the metal foil on the outer peripheral surface and connects to an electrode support rod disposed along the lamp axis, and a plurality of metal foils are pressed on the outer peripheral surface of the ring-shaped member so that they follow the surface of the glass member at least in the vicinity of the ring-shaped member. It is provided with a pressure welding member of the shape.

The pressure contact member may be configured as a member that presses the metal foil on the outer peripheral surface of the annular member. For example, the pressure-welding member may be composed of a member that tightly tightens or holds the metal foil, or is strongly wound so that the metal foil is pressed across the entire circumferential direction. Additionally, the pressure-welded member may be provided with uneven portions that contact at least the vicinity of both edges of the metal foil. For example, the pressure-welded member is made of metal and welded to metal foil.

Considering proper pressure contact, in the pressure contact member, the axial length of the area where the metal foil is pressed on the surface of the glass member should be in the range of 0.5 to 2.0 times the axial length of the annular member. In addition, the pressure-welded member may be configured so that an overlapping portion is provided at a location facing the predetermined metal foil.

Meanwhile, considering that the metal foil follows the surface of the glass member, the width of the metal foil along the main direction can be determined to satisfy the following equation.

1.2L/2×sin(90 L/πD)

1.2

However, D (mm) represents the diameter of the glass member, and L (mm) represents the width of the metal foil. In particular, it is better to set it to 1.00 mm or less, 0.8 mm or less, etc.

In the method of manufacturing a discharge lamp according to one embodiment of the present invention, a plurality of metal foils are arranged in the main direction along the surface of a pillar-shaped glass member, the metal foil is welded to the outer peripheral surface of a conductive ring-shaped member in contact with an electrode support rod, and the plurality of metal foils are arranged in the main direction. A ring-shaped metal pressure-welded member is welded to a plurality of metal foils on the outer peripheral surface of the ring-shaped member so that the metal foil follows the surface of the glass member at least in the vicinity of the ring-shaped member. The pressure welding member presses the metal foil toward the outer peripheral surface of the annular member, and deforms the metal foil so as to follow the surface of the glass member at least in the vicinity of the annular member in the stage before welding the mount component and the sealed tube.

The manufacturing method of the discharge lamp which is one form of this invention prepares a plurality of metal foils whose partial height is 1.2 mm or less when brought into contact with the column-shaped glass member of a mount component, and applies the metal foil to the mount component. is welded to the outer peripheral surface of the conductive ring-shaped member, and the ring-shaped metal pressure-welded member is welded to a plurality of metal foils on the outer peripheral surface of the ring-shaped member. Here, “part height” represents the distance in the vertical direction between the edge of the metal foil and the surface of the glass member when the width direction center of the flat metal foil is in contact with the glass member. When the part height is set to 1.2 mm or less, the edge of the metal foil approaches or contacts the surface of the glass member at a stage before welding the mount component and the sealing tube.

According to the present invention, in a short arc type discharge lamp, etc., mount parts can be sealed to prevent wrinkles, etc. from forming in the metal foil.

1 is a schematic cross-sectional view of a short arc-type discharge lamp according to this embodiment.
Figure 2 is a plan view of the mount component showing the arrangement of the metal foil and the pressure-welded member.
Figure 3 is a diagram showing one sheet of metal foil before welding the pressure-welded member.
Figure 4 is a cross-sectional view showing a part of the vicinity of the end of the metal foil in Figure 1.
Figure 5 is a diagram showing the relationship between the width and height of the metal foil and the diameter of the glass member.
Figure 6 is a cross-sectional view of the inner metal ring before welding the pressure-welded member to the metal foil.

Below, embodiments of the present invention will be described with reference to the drawings.

1 is a schematic cross-sectional view of a short arc-type discharge lamp according to this embodiment.

The short arc type discharge lamp 10 is a discharge lamp in which an anode 14 and a cathode 16 are arranged to face each other in a light emitting tube 12 made of quartz glass, and a bag of quartz glass is placed at both ends of the light emitting tube 12. The pipes 20 and 60 are integrally formed to face each other. Both ends of the sealing tubes 20 and 60 are closed with tubes 80A and 80B.

Inside the sealing tubes 20 and 60, there are parts (hereinafter referred to as mount parts) that support the anode 14 and the cathode 16 and seal the discharge space 11 in the light emitting tube 12. 18A and 18B) are each enclosed. The mount component 18A includes a cylindrical thick glass tube (hereinafter referred to as a glass tube) 24, a columnar glass member 34, and a plurality of metal foils 36. The mount part 18B also has a similar configuration. Mercury and rare gases are enclosed in the discharge space 11.

Within the sealing tube 20, a conductive electrode support rod 22 supporting the anode 14 is arranged along the electrode axis E (sealing tube axis). The electrode support rod 22 is inserted into the axial hole 24A formed in the glass tube 24 and is held by the glass tube 24.

Meanwhile, on the end side of the sealing tube, the conductive lead rod 28 is arranged to face the electrode support rod 22. The electrode support rod 22 and the lead rod 28 are inserted into the holes (concave portions) 34A, 34B provided at both ends of the glass member 34, and the glass member 34 is an electrode support rod ( 22) and the lead rod (28). The lead rod 28 is connected to an external lead wire (not shown) connected to a power supply unit (not shown).

At both ends of the glass member 34, metal rings (ring-shaped members) 26 and 32 are disposed, respectively, and the electrode support rod 22 and the lead rod 28 are connected to the axial holes 26A of the metal rings 26 and 32, respectively. 32A). The metal ring 26 (hereinafter referred to as the inner metal ring) close to the light emitting tube 12 is sandwiched between the disk-shaped disc foils 42 and 44, and the other metal ring (hereinafter referred to as the outer metal ring) ) 32 is similarly inserted into a disk-shaped disc foil (not shown here).

Between the inner metal ring 26 and the outer metal ring 32, a plurality of strip-shaped metal foils (for example, molybdenum foil) 36 are placed along the outer surface of the glass member 34 along the ramp axis E. It extends in the direction, and both ends are welded to the outer peripheral surfaces 26S and 32S of the inner metal ring 26 and the outer metal ring 32. The outer metal ring 32 electrically connects the lead rod 28 and the metal foil 36, and the inner metal ring 26 electrically connects the metal foil 36 and the electrode support rod 22. As a result, power is supplied to the anode 14 from the lead rod 28 connected to the power supply unit.

On the outer peripheral surface 26S of the inner metal ring 26, a metal annular press-welded member 50 is provided. The annular pressure-welding member 50 presses the metal foil 36 toward the glass member 34 so that the metal foil 36 follows the outer surface of the glass member 34, and presses the end of the metal foil 36 toward the glass member ( 34) (inner metal ring 26) is tightly tightened. That is, the pressure contact member 50 is not a member that covers the surroundings of the glass member 34 and the inner metal ring 26, but presses the metal foil 36 toward the outer surface side of the glass member 34. It is composed as an absence that does.

FIG. 2 is a top view of the mount component 18A showing the arrangement of the metal foil 36 and the pressure contact member 50. Here, the figure which looked at the mount part 18A from the axial direction before sealing the sealing pipe 20 is shown. However, the thickness of the metal foil 36 and the pressure-welded member 50 is exaggerated. In addition, both axial edges 36K1 and 36K2 of the metal foil 36 are actually tapered in a knife edge shape.

The metal foil 36 is made of six sheets of metal foil having the same width, and is arranged at a predetermined distance from each other along the main direction of the glass member 34. Here, since the six sheets of metal foil 36 are arranged symmetrically with respect to the axis E, the metal foils 36 are arranged in the main direction at equal intervals.

The pressure-welding member 50 is composed of a ring-shaped metal member having a circumference of approximately one circumference of the glass member 34 (inner metal ring 26) and provided with an overlapping portion 50T. there is. Here, the pressure-welded member 50 is made of metal foil. The pressure-welded member 50 is welded to the metal foil 36 on the outer peripheral surface 26S of the inner metal ring 26.

FIG. 3 is a diagram showing one sheet of metal foil 36 before welding the pressure-welded member 50. The metal foil 36 is a flat strip-shaped metal, and is hard and difficult to bend in the width direction. When such a metal foil 36 is placed on the outer surface of the glass member 34, as the distance from the contact portion increases, a gap ΔT is created between the glass member 34 and the metal foil 36 (hereinafter referred to as a portion height). do). Additionally, as the width L of the metal foil 36 becomes longer, the partial height ΔT also increases.

The pressure contact member 50 bends the metal foil 36 along the main direction of the glass member 34 at the outer peripheral surface 26S of the inner metal ring 26 and its vicinity so that the metal foil 36 has a width L. A force is applied to bring it into contact with the glass member 34 throughout.

FIG. 4 is a cross-sectional view showing a part of the vicinity of the end of the metal foil 36 in FIG. 1.

The pressure-welded member 50 has an axial width T, and both edges 50E1 and 50E2 along its main direction are positioned on the surfaces of the glass member 34 and the glass tube 24, respectively. That is, the pressure contact member 50 extends in the lamp axis direction across the glass member 34, the inner metal ring 26, and the glass tube 24. In addition, in FIG. 4, the thickness of the pressure-welded member 50, the disc foils 42 and 44, and the metal foil 36 are exaggerated, and the outer diameters of the glass member 34, the inner metal ring 26, and the glass tube 24 are exaggerated. may be approximately the same.

The axial length (hereinafter referred to as the pressure contact length) J of the area where the metal foil 36 is pressed against the pressure contact member 50 on the outer surface of the glass member 34 is the thickness of the inner metal ring 26 ( It is determined in the range of 0.5 to 2.0 times the axial length (RT). If it is less than 0.5 times, the metal foil 36 cannot be sufficiently pressed on the surface of the glass member 34, while if it exceeds 2.0 times, the welded area of the glass member 34 and the sealing tube 20 decreases, resulting in a sealing structure. affects the reliability of

On the back surface of the press-welded member 50, uneven portions are formed at contact points with the end portion 36T of the metal foil 36, particularly near both edges 36K1 and 36K2. Here, by performing embossing, irregularities are formed on the back surface (and surface) of the pressure-welded member 50. Additionally, irregularities may be formed on other backside (and surface) portions, and the irregularities are not limited to embossing.

Since the metal foil 36 depends on the power (current value), its width L cannot be made extremely short. On the other hand, it is required to set the width L to suppress the partial height ΔT of the metal foil 36. The width L of the metal foil 36 can be determined from the relationship between the allowable range of this partial height ΔT and the diameter D of the glass member 34.

FIG. 5 is a diagram showing the relationship between the width (L) and partial height (ΔT) of the metal foil and the diameter (D) of the glass member 34. Considering θ"≒θ／2, sin(θ／2)≒ΔT÷(L/2), the minor height (ΔT) can be expressed by the following equation. However, the symbol 36' in Figure 5 is, Indicates the position of the virtual metal foil 36.

ΔT = L/2×sin(90 L/πD)·····(1)

It is empirically derived that this secondary height (ΔT) is 1.2 or less. Therefore, the width (L) of the metal foil 36 with respect to the diameter (D) of the glass member 34 is determined so as to satisfy the following equation. However, the diameter (D) of the glass member 34 is 15 D It is assumed that the range (mm) of 35 is satisfied.

1.2　·····(2)L/2×sin(90 L/πD)

1.2 ·····(2)

FIG. 6 is a cross-sectional view of the inner metal ring 26 before welding the pressure-welded member 50 to the metal foil 36. The manufacturing method of the discharge lamp will be explained using FIG. 6. Additionally, in FIG. 6, the gap between the press-welded member 50 and the metal foil 36 is exaggerated.

A plurality of metal foils 36 are arranged in the axial direction along the surface of the columnar glass member 34, and the end portion 36T of the metal foil is the outer peripheral surface of the inner metal ring 26 into which the electrode support rod 22 is inserted ( 26S). Then, a process of welding the pressure-welded member 50 to the metal foil 36 along the outer peripheral surface 26S of the inner metal ring 26 is performed.

When welding the pressure-welded member 50 to the metal foil 36, spot welding is performed at least at one location for each metal foil 36 (see arrow). On the other hand, with respect to the metal foil 36 facing the overlapping portion 50T of the press-welded member 50, spot welding is performed at one to two or more locations at both ends. By welding in this way, the metal foil 36 is tightly tightened with the pressure welding member 50. Direct welding may be performed between the press-welded member 50 and the inner metal ring 26, but for the sake of manufacturing efficiency, it does not need to be performed.

After welding the pressure-welded member 50 and the metal foil 36 is completed, the process proceeds to the sealing process. The sealing tube 20 is heated with a gas burner or the like during the sealing process to reduce its diameter, and is welded to the glass tube 24 and the glass member 34. Through these operations, a discharge lamp is manufactured.

According to this embodiment, a plurality of metal foils 36 are disposed along the lamp axis direction on the outer surface of the columnar glass member 34, and an inner metal ring 26 connected to the electrode support rod 22 is formed. In the discharge lamp 10 in which the metal foil 36 is welded to the outer peripheral surface 26S, the annular pressure-welded member 50 is provided with the metal foil 36 on and near the outer peripheral surface 26S of the inner metal ring 26. is pressed toward the center of the inner metal ring (glass member) and tightened tightly.

By installing such a pressure contact member 50, floating of the metal foil 36 from the outer surface of the glass member 34 can be suppressed. As a result, it is possible to prevent wrinkles and flaking from occurring at least at the end portion 36T of the metal foil 36 during sealing. In particular, both axial edges 36K1 and 36K2 (see FIG. 2) of the metal foil 36 are actually tapered in a knife edge shape. Therefore, by suppressing the occurrence of floating by the pressure contact member 50, the knife edge-shaped portion can be sealed along the surface of the glass member 34.

Additionally, both edges 36K1 and 36K2 of the metal foil 36 contact the uneven portions formed on the press-welded member 50. By this, both edges 36K1 and 36K2 of the metal foil 36 can be strongly pressed, and floating of the metal foil 36 can be reliably suppressed. Moreover, by the above equation (2), the height of the portion can be made low without the width L of the metal foil 36 becoming longer than necessary with respect to the diameter of the glass member 34.

Additionally, the number of metal foils 36 is not limited to 6, but may be more or less than that. In this case, the thickness and number of metal foils 36 may be adjusted by considering the heat capacity of the metal foil 36 and the welded area during encapsulation. In addition, the pressure-welded member 50 is made to have a circumference of approximately one circumference of the glass member 34 (inner metal ring 26), but it may be made to be two or three circumferences, or multiple circumferences may be pressed.

[Example]

In order to show that the discharge lamp of this embodiment is effective, a short arc type discharge lamp (Example 1, Example 2) and a conventional short arc type discharge lamp (comparative example) with different diameters of the glass member and width of the metal foil were used. was manufactured, and a comparative experiment was conducted on the occurrence of wrinkles and lifting of (the ends of) the metal foil. A visual confirmation experiment was conducted regarding the occurrence of wrinkles and flaking. Table 1 shows the results of Comparative Example 1, Example 1, and Example 2.

As shown in Table 1, wrinkles and lifting occurred at the ends of the metal foil in the comparative example, but did not occur in Examples 1 and 2.

10: Discharge lamp
20: Bongjigwan
26: Inner metal ring (ring-shaped member)
34: glass member
36: Metal foil
50: Pressure-welded member

Claims (8)

A pillar-shaped glass member,
A plurality of metal foils extending along the surface of the glass member,
A conductive ring-shaped member in contact with the plurality of metal foils on the outer peripheral surface and connected to the electrode support rod, and
A mount part provided with an annular pressure contact member for pressing the plurality of metal foils on the outer peripheral surface of the annular member so as to follow the surface of the glass member at least in the vicinity of the annular member is formed integrally with the light emitting tube. A discharge lamp characterized by being enclosed within a sealing tube. A pillar-shaped glass member,
A plurality of metal foils extending along the surface of the glass member,
A conductive ring-shaped member in contact with the plurality of metal foils on the outer peripheral surface and connected to the electrode support rod, and
It has uneven portions that contact at least near both edges of the plurality of metal foils, and the plurality of metal foils are placed on the outer peripheral surface of the annular member such that the plurality of metal foils follow the surface of the glass member at least in the vicinity of the annular member. It is provided with an annular pressure contact member biased toward the surface of the glass member,
A discharge lamp characterized in that the glass member, on which the plurality of metal foils are urged toward the surface of the glass member by the press-welding member, is welded to the sealing tube within a sealing tube formed integrally with the light emitting tube. According to claim 1 or 2,
In the pressure contact member, the axial length of the area where the metal foil is pressed on the surface of the glass member is in a range of 0.5 to 2.0 times the axial length of the annular member. According to claim 1 or 2,
A discharge lamp characterized in that the pressure-welded member is provided with an overlapping portion at a location facing a predetermined metal foil. According to claim 1 or 2,
A discharge lamp, characterized in that the width along the main direction of the metal foil is determined to satisfy the following equation.
L/2×sin(90 L/πD) 1.2
However, D (mm) represents the diameter of the glass member, and L (mm) represents the width of the metal foil. According to claim 1 or 2,
The press-welded member is metal,
A discharge lamp, characterized in that the press-welded member is welded to the metal foil. A plurality of metal foils are arranged in the main direction along the surface of the pillar-shaped glass member,
Welding the metal foil to the outer peripheral surface of the conductive ring-shaped member in contact with the electrode support rod,
Pressing the annular pressure contact member against the plurality of metal foils on the outer peripheral surface of the annular member so that the plurality of metal foils follow the surface of the glass member at least in the vicinity of the annular member,
The mount part formed through arrangement of the metal foil, welding of the metal foil to the outer peripheral surface of the annular member, and pressing of the pressure-welding member to the plurality of metal foils is enclosed in a sealing tube formed integrally with the light emitting tube. Method for manufacturing a discharge lamp. delete

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