JP5134054B2 - Metal vapor discharge lamp and lighting device - Google Patents

Description

  The present invention relates to a metal vapor discharge lamp and an illuminating device, and more particularly to a technique for improving tube axis misalignment in a triple tube structure lamp.

  As a conventional metal vapor discharge lamp, for example, as shown in FIG. 16A, there is a triple-tube structure in which an inner tube 602 in which a discharge tube 601 is housed is further covered with an outer tube 606. With such a structure, even if the inner tube 602 may be damaged due to the rupture of the discharge tube 601, fragments generated by the rupture or damage are retained in the outer tube 606, which improves safety. I can expect. In particular, a compact metal vapor discharge lamp having a triple-pipe structure is used for lighting equipment in commercial facilities such as stores, and therefore, there is a high interest in safety for both users and lamp / lighting equipment manufacturers.

  Further, as described in Patent Document 1, a regulating member 604 that is supported by the outer surface of the inner tube 602 on the outer side of the distal end 603 of the inner tube 602 and on the inner side of the outer tube 606, and contacts the inner surface of the outer tube 606. The inner tube 602 and the outer tube 606 are mutually regulated in position. FIG. 16B is a perspective view showing the shape of the regulating member 604. The restricting member 604 has an effect of receiving, when the discharge tube 601 is ruptured, the fragments when the tip portion 603 of the inner tube 602 is broken before reaching the closed portion 607 of the outer tube 606. As a result, the restricting member 604 is also expected to have an explosion-proof property that prevents the blocking portion 607 of the outer tube 606 from being damaged even if the discharge tube 601 is ruptured.

Utility Model Registration No. 3144888

However, when a triple-tube lamp having the regulating member 604 is actually manufactured, a lamp in which the outer tube 606 and the base 605 are displaced may be formed as shown in part A of FIG. . As a cause thereof, when the inner tube 602 and the base 605 are fixed in the lamp assembly process, due to manufacturing errors, the tube axis y of the inner tube 602 and the central axis x of the base 605 (the central axis in the longitudinal direction of the base 605). ) Does not match. When the tube axis y of the inner tube 602 is inclined with respect to the central axis x of the base 605 as described above, the outer surface of the inner tube 602 is supported by the regulating member 604 that comes into contact with the inner surface of the outer tube 606, thereby The tube axis z of the tube 606 is also inclined with respect to the center axis x of the base 605. When such a mismatch between the tube axis z of the outer tube 606 and the center axis x of the base 605 occurs, the lamp 600 holds the outer tube 606 when the base 605 is rotationally mounted on a socket (not shown) of a lighting fixture. Even if the whole is rotated around the tube axis z, the base 605 does not rotate around the central axis x, so that the operability when the lamp is mounted is lowered.

  The present invention provides a metal vapor discharge lamp capable of reducing the inclination between the tube axis of the outer tube and the central axis of the base while effectively preventing breakage of the closed portion of the outer tube when the discharge tube is ruptured. The purpose is to do.

  In order to achieve the above object, a metal vapor discharge lamp according to the present invention comprises an outer tube having an opening at one end and a closed portion at the other end, a base attached to the opening of the outer tube, and one end The inner tube disposed in the outer tube so that the tip portion which is the other end is located on the closed portion side in a state where the sealing portion formed on the base is fixed to the base, and is housed in the inner tube. The discharge tube is disposed in a state where at least a portion is located inside the outer tube and outside the tip of the inner tube, and a gap is provided between the outer tube and the inner surface of the outer tube. And a protected member.

In the metal vapor discharge lamp according to the present invention, since at least a part of the protective member is located inside the outer tube and outside the tip of the inner tube, even if the discharge tube ruptures, the closed portion of the outer tube is damaged. Can be prevented.
In addition, the metal vapor discharge lamp according to the present invention has a gap between the protective member disposed in the outer tube and the outer surface of the inner tube. Therefore, the outer tube is in contact with the protective member, but the inner tube is not in contact with the protective member, or is in contact with the inner tube at a level that does not restrict the shaft. As long as it does not contact the member, the fixing position of the outer tube and the base is not affected by the displacement of the inner tube. As a result, even when the tube axis of the inner tube does not coincide with the axis of the base, the inclination between the tube axis of the outer tube and the central axis of the base can be reduced.

The partially broken side view which shows the illuminating device which concerns on 1 aspect of this invention Sectional drawing which shows the discharge tube of the metal vapor discharge lamp which concerns on 1 aspect of this invention The partially broken side view which shows the metal vapor discharge lamp which concerns on 1 aspect of this invention The perspective view which shows the protection member of the metal vapor discharge lamp which concerns on 1 aspect of this invention. The figure for demonstrating the protection member which concerns on 1 aspect of this invention The figure which shows the assembly method of the metal vapor discharge lamp which concerns on 1 aspect of this invention. The figure for demonstrating the protection member which concerns on the modification 1. The figure for demonstrating the protection member which concerns on the modification 2. The figure for demonstrating the protection member which concerns on the modification 3. The figure for demonstrating the protection member which concerns on the modification 4. The figure for demonstrating the protection member which concerns on the modification 5. The figure for demonstrating the protection member which concerns on the modification 6. The figure for demonstrating the metal vapor discharge lamp which concerns on the modification 7. The figure for demonstrating the metal vapor discharge lamp which concerns on the modification 8. The figure for demonstrating the metal vapor discharge lamp which concerns on the modification 9. It is a figure which shows the metal vapor discharge lamp which concerns on the conventional one aspect | mode, Comprising: (a) is a partially broken side view which shows a metal vapor discharge lamp, (b) is a perspective view which shows the shape of the conventional control member.

  Hereinafter, a metal vapor discharge lamp and a lighting device according to the present embodiment will be described with reference to the drawings. In addition, the scale of the member in each drawing differs from an actual thing. In the present invention, the sign “˜” indicating a numerical range includes numerical values at both ends.

[Lighting device]
FIG. 1 is a partially cutaway side view illustrating a lighting device according to one embodiment of the present invention. As shown in FIG. 1, the illuminating device 1 which concerns on 1 aspect of this invention is a spotlight illuminating device, Comprising: The metal vapor discharge lamp 10 and the lighting fixture 20 with which the said lamp | ramp 10 is arrange | positioned are provided.

  The metal vapor discharge lamp 10 is a metal vapor discharge lamp having a triple tube structure including a discharge tube 100, an inner tube 200, a protective member 300, an outer tube 400 and a base 500. Details thereof will be described later.

  The luminaire 20 includes a reflecting mirror 22 having a concave reflecting surface 21 that reflects light emitted from the metal vapor discharge lamp 10 forward, a socket 23 for mounting the lamp incorporated in the reflecting mirror 22, and a wall. And an attachment 24 for attaching the reflecting mirror 22 to the ceiling.

  In the reflecting mirror 22, the light extraction opening 25 provided on the front surface is not covered with a cover such as a glass plate and is in an open state. The metal vapor discharge lamp 10 having this configuration is excellent in heat dissipation. However, when the inner tube 200 and the outer tube 400 are damaged due to the rupture of the discharge tube 100, fragments generated by the rupture or damage to the outside of the lighting fixture 20. There is a risk of scattering. Therefore, it is preferable to attach the metal vapor discharge lamp 10 to the lighting fixture 20 where the outer tube 400 is not easily damaged.

  The socket 23 is electrically connected to a lighting device (not shown) embedded in a wall or ceiling via a supply line 26, and a ballast 500 is provided if the base 500 of the metal vapor discharge lamp 10 is inserted into the socket 23. Is supplied to the metal vapor discharge lamp 10.

  The attachment 24 has an arm 27 that is rotatably attached to a wall or ceiling, and a reflecting mirror 22 is pivotally attached to the tip of the arm 27. The direction of light emitted from the illumination device 1 can be adjusted by rotating the arm 27 or the reflecting mirror 22. The lighting device according to the present invention is not limited to a spotlight lighting device, and may be a lighting device for other purposes.

[Metal vapor discharge lamp]
FIG. 2 is a sectional view showing a discharge tube housed in a metal vapor discharge lamp.
As shown in FIG. 2, the discharge tube 100 includes a main tube portion 102 having a discharge space 101 hermetically sealed therein, and a tube axis of the discharge tube 100 from the main tube portion 102 (the longitudinal direction of the metal vapor discharge lamp 10). The narrow tube portions 103 and 104 arranged so as to extend on both sides in the direction (which coincides with the lamp axis X, which is the central axis of the direction), and a joint portion that fills the gap between the main tube portion 102 and the thin tube portions 103 and 104 An envelope 107 including 105 and 106 is provided.

  The envelope 107 is a shrink-fit type made of alumina ceramic, for example. The envelope 107 is not limited to the one formed of alumina ceramic, and may be formed of other translucent ceramic (for example, rare earth alumina garnet ceramic), quartz glass, or the like. In the drawing, the discharge tube 100 is a shrink-fit type formed by joining the main tube portion 102, the thin tube portions 103 and 104, and the joint portions 105 and 106, but the main tube portion 102, the thin tube portions 103 and 104, and An integrated type in which the joint portions 105 and 106 are integrally formed may be used. Further, the main pipe portion 102 may be formed by joining a plurality of members.

  The discharge space 101 is filled with a predetermined amount of a metal halide that is a luminescent material, a rare gas that is a starting auxiliary gas, and mercury that is a buffer gas. Examples of the metal halide include sodium iodide, dysprosium iodide, holmium iodide, thulium iodide, thallium iodide, cerium iodide, calcium iodide, lithium iodide, indium iodide, and scandium iodide. It is done. The metal halide is appropriately determined depending on the emission color.

The discharge tube 100 has a pair of electrodes 108 and 109 whose distal ends are opposed to each other in the discharge space 101 of the main tube portion 102 and whose proximal ends are inserted into the narrow tube portions 103 and 104.
The electrodes 108 and 109 have electrode rods 110 and 111 and electrode coils 112 and 113 provided at the tip portions (end portions on the side facing each other in the discharge space 101) of the electrode rods 110 and 111. The other end portions of the electrodes 108 and 109 are joined to one end portions of the power feeding bodies 114 and 115 in the narrow tube portions 103 and 104, and the power feeding bodies 114 and 115 are formed from the frit poured into the narrow tube portions 103 and 104. It is sealed by the sealing materials 116 and 117.

  FIG. 3 is a partially broken side view showing a metal vapor discharge lamp according to one embodiment of the present invention. The power feeders 114 and 115 are electrically connected to the shell portion 502 and the eyelet portion 503 of the base 500 via the power supply lines 118 and 119, the metal foils 120 and 121, and the external lead wires 122 and 123, respectively. The lead wires 122 and 123 are, for example, first external lead wires 124 and 125 made of molybdenum and having a diameter of 0.7 [mm], and second external lead wires 126 and 125 made of nickel and having a diameter of 0.6 [mm]. 127, the first external lead wires 124 and 125 are connected to the metal foils 120 and 121, and the second external lead wires 126 and 127 are connected to the base 500. Since metal wires such as nickel have elasticity, workability such as connection between lead wires and caps and alignment of optical centers is improved.

  One power supply line 118 is covered with a sleeve 128 made of, for example, quartz glass at a portion facing the other power supply line 119 and the power supply body 115 connected to the power supply line 119. With such a configuration, even if a leak occurs in the discharge tube 100 at the end of the lamp life, there is an effect of suppressing an unexpected large current from continuing to flow due to a discharge generated between members having opposite polarities. As a result, it is possible to prevent problems such as damage to the lighting device.

  The inner tube 200 is, for example, a single-sealed airtight container including a sealing portion 202, a tip portion 203, and an intermediate portion 205. The sealing part 202 is formed, for example, by crushing sealing by a pinch seal method, and constitutes the base side end of the inner tube 200. One end of the power supply lines 118 and 119, the entire metal foils 120 and 121, and one end of the lead-in wires 122 and 123 are sealed in the sealing portion 202. The distal end portion 203 constitutes an end portion on the opposite side of the base 500 of the inner tube 200, and faces the closing portion 401 of the outer tube 400.

  The tip portion 203 has a tip-off portion 201 that is the remaining portion of the exhaust pipe used when evacuating the inside of the inner pipe 200. By evacuating the inner tube 200, metal members such as the power feeders 114 and 115 and the power supply lines 118 and 119 can be prevented from being exposed to high temperatures and being oxidized. It should be noted that the metal member can be prevented from being oxidized by filling the inner tube 200 with an inert gas such as nitrogen instead of evacuating the inner tube 200.

  For example, when the distal end portion 203 has a substantially hemispherical shape or a flat shape, the outer diameter of the intermediate portion 205 is 13 [mm] to 17 [mm], and the thickness is 1 [mm] to 2 [mm]. In the inner tube 200, the intermediate portion 205 has a substantially cylindrical shape, for example, and the envelope 107 of the discharge tube 100 is disposed in the intermediate portion 205. The shape of the intermediate portion 205 is not limited to a substantially cylindrical shape, and may be a cylinder other than a cylinder such as a polygonal or elliptical cylinder. Further, the inner diameter and the outer diameter of the intermediate portion 205 are not necessarily uniform along the tube axis direction of the inner tube 200. For example, the inner diameter and the outer diameter at a position corresponding to the main tube portion 102 of the discharge tube 100 are the same. A shape that is larger than the inner and outer diameters at positions other than the above, that is, a middle-bulged shape having a bulged portion in part. Thereby, it can suppress that the temperature of the discharge tube 100 rises excessively.

  The inner tube 200 is made of, for example, quartz glass. The inner tube 200 is not limited to the one formed of quartz glass, and may be formed of a translucent ceramic such as alumina ceramic, hard glass, or the like. The base 500 side of the inner pipe 200 is coupled to the base 500 or the outer pipe 400 with an adhesive such as cement (not shown). It is preferable that the gap d between the inner tube 200 and the outer tube 400 is designed to be 1 [mm] to 3 [mm] on average.

  The outer tube 400 has a bottomed cylindrical shape including an opening (neck portion) 402, a closing portion 401, and an intermediate portion 403 between the opening 402 and the closing portion 401. When the inner tube 200 is damaged by the rupture, it plays a role of preventing the fragments generated by the rupture or damage from being scattered. Therefore, even if the opening 25 as shown in FIG. 1 is used for the lighting fixture 20 that is not covered with the cover, fragments are not scattered. Note that the closing portion 401 is preferably substantially hemispherical or flat. Moreover, it is not always necessary to close with the same member. For example, another member such as metal or ceramic may be used.

  In order to ensure the compactness of the metal vapor discharge lamp 10, the intermediate part 403 is preferably substantially the same cylindrical shape as the intermediate part 205 of the inner tube 200. Further, the gap between the inner surface of the intermediate portion 403 of the outer tube 400 and the outer surface of the intermediate portion 205 of the inner tube 200 is substantially uniform in a direction orthogonal to the tube axis of the outer tube 400 (which coincides with the lamp axis X). Preferably there is. In order to secure a clearance when the outer tube 400 is put on the inner tube 200 in the assembly process, the gap is preferably designed so as to be 1 [mm] to 3 [mm] on average.

  The shape of the intermediate portion 403 is not limited to a substantially cylindrical shape, and may be a cylindrical shape other than a cylinder such as a polygonal shape or an elliptical cylindrical shape. Further, the inner diameter and the outer diameter of the intermediate portion 403 are not necessarily uniform along the tube axis direction of the outer tube. For example, the inner diameter and the outer diameter at a position corresponding to the main tube portion 102 of the discharge tube 100 are other than that. It may be a shape that is larger than the inner diameter and the outer diameter of the position, that is, a middle-bulged shape having a bulging portion in part. By reducing the temperature rise of the outer tube due to the heat from the discharge tube by providing the bulging portion, it is possible to widen the selection range of the suitable lighting fixture 20 with a margin from the strain point of the hard glass. . Furthermore, the safety when the discharge tube is broken is also improved. In that case, it is preferable that the gap is designed to be 5 [mm] at the maximum.

  Furthermore, in order to prevent the outer tube 400 from falling, an inner convex portion may be provided in the vicinity of the opening 402, and a groove-shaped engaged portion may be provided in the base 500, for example. In that case, it may be a case through an adhesive such as an inorganic adhesive. Further, when the base 500 is not provided with an engaged portion, a convex portion (not shown) is provided inside the outer tube 400, and an adhesive is disposed between the convex portion and the base 500. May be combined. The outer tube 400 is made of hard glass, for example. The outer tube 400 is not limited to the one made of hard glass, and may be made of a translucent ceramic such as alumina ceramic, quartz glass, or the like.

  Regarding adapting to a compact lighting fixture, the outer tube 400 is preferably such that the outer diameter of the neck near the sealing portion 202 is 23 mm or less and the maximum outer diameter is 27 mm or less. Furthermore, if the outer diameter of the neck portion of the lamp is also small as described above, it becomes possible by reducing the opening diameter of the reflector neck portion of the fixture, so that the reflection efficiency of the fixture can be increased.

  The outer tube 400 is fixed to the base 500 using an adhesive (not shown) such as cement. The inside of the outer tube 400 may be in an atmospheric state in which the inside and the outside of the outer tube 300 communicate with each other via a vent hole (not shown) of a base 500 described later, or a vent hole (not shown). It may be in a depressurized state by closing the gas or may be filled with an inert gas. In the metal vapor discharge lamp 10, the maximum outer diameter of the outer tube intermediate portion 403 is 20 [mm] to 27 [mm], the outer diameter of the neck portion is 20 [mm] to 23 [mm], and the outer tube intermediate portion is thick. Is preferably 1 [mm] to 2 [mm].

FIG. 4 is a perspective view showing an example of the protection member 300. The protection member 300 is used in place of the conventional restriction member. Unlike the restriction member, the protection member 300 does not have a function of restricting the tube axis y of the inner tube 200 and the tube axis z of the outer tube 400, and has only an explosion-proof performance. Have. For this reason, the member name was made into the protection member.
As shown in FIG. 4, the protection member 300 includes a disk-shaped plate-shaped portion 301, and four L-shaped claws 303 to 306 are equally spaced along the outer peripheral portion 302 of the plate-shaped portion 301. It is extended. The protective member 300 shown in FIG. 4 is produced by bending the plate-like portion 301 and the claws 303 to 306 from a single plate material, but the claws 303 to 306 and the plate-like portion 301 are produced separately. These may be fixed by welding or caulking to the outer peripheral portion 302 of the plate-like portion 301. The material of the protective member 300 is preferably a material having heat resistance of 200 [° C.], preferably 300 [° C.] so as to withstand the heat generated when the metal vapor discharge lamp 10 is turned on, in addition to the elastic material.
For example, the protective member 300 is a metal such as aluminum or stainless steel from the viewpoint of elasticity and heat resistance, and preferably has a thickness of 0.1 [mm] to 0.5 [mm].
FIG. 5 is an enlarged view of the vicinity of the outer tube blocking portion 401 in FIG. The outer diameter of the plate-shaped portion 301 is smaller than the inner diameter of the outer tube 400, and the maximum outer diameter of the protective member 300 including the claws 303 to 306 is larger than the inner diameter of the outer tube 400. Therefore, when the protective member 300 is inserted into the outer tube 400, the claws 303 to 306 are reduced in diameter, but due to the restoring force due to elasticity, a pressure is generated toward the inner surface of the outer tube 400, and as a result, the protective member 300 is It is installed on the inner surface of the outer tube 400.

  In this case, as shown in FIG. 5, by adjusting the position of the protection member 300 in the lamp axis X direction, at least a part of the protection member 300 is located inside the outer tube 400 and the tip of the inner tube 200. It arrange | positions so that it may be located in the outer side of the part 203. FIG.

  In this state, the protection member 300 is in contact with the inner surface of the outer tube 400, but is not in contact with the outer surface of the inner tube 200. That is, the protective member 300 is disposed in a state where a gap is provided between the protective member 300 and the outer surface of the inner tube 200. When the protective member 300 is not provided for the scattering of the fragments when the inner tube 200 is broken into the outer tube blocking portion 401 when the discharge tube 100 is broken, the diffusion rate of the enclosed gas immediately after the breakage is higher than the velocity of the fragments. Since it is larger, the sealed gas reaches the outer tube 400 first, and the scattered fragments are pushed back by the gas bounced back to the inner surface of the outer tube 400, thereby causing a decrease in the speed of the fragments. When the said clearance gap is too small, the speed reduction of a fragment will not become enough and an explosion-proof effect is low. On the other hand, if the gap is too large, the overall shape of the lamp becomes large and the compactness is lacking.

  However, by providing the protective member 300, the distance 204, which is the distance in the tube axis direction of the inner tube 200 in the gap between the tip-off portion 201 of the inner tube 200 and the plate-like portion 301, is equal to or less than 10 [mm]. A distance 406, which is a vertical distance between the inner surface of the blocking portion 401 of the tube 400 and the plate-like portion 301 of the protection member 300, with respect to the plate-like portion 301 of the protection member 300 is 10 [mm] or less, and compactness can be secured. it can.

As described above, in the metal vapor discharge lamp 10, the protective member 300 is in a state where a gap is provided between the protective member 300 and the outer surface of the inner tube 200, or in a state where the protective member 300 is in contact with the inner tube 200 at a level that does not restrict the shaft. It is attached to the inner surface of the tube 400. That is, the protection member 300 does not regulate the tube axis y of the inner tube 200 and the tube axis z of the outer tube. For this reason, the outer tube 400 can be coupled to the base 500 even if the tube axis y of the inner tube 200 is inclined within the space in which the inner tube 200 is accommodated in the outer tube 400 and the base 500. Therefore, the deviation between the tube axis z of the outer tube 400 and the center axis x of the base 500 can be reduced.
The protective member 300 is disposed inside the outer tube 400 and outside the tip-off portion 201 of the inner tube 200. Therefore, even when the inner tube 200 is damaged when the discharge tube 100 is ruptured, the protective member 300 can easily prevent the outer tube 400 from being damaged.
As shown in FIG. 5, the entire protective member 300 is located inside the closed portion 401 of the outer tube 400 and outside the distal end portion 203 of the inner tube 200. In this configuration, since the distance between the distal end portion 203 of the inner tube 200 and the protective member 300 is large, the effect of preventing the outer tube 400 from being damaged when the discharge tube 100 is ruptured can be further expected. Note that the protection member 300 does not necessarily have to be located entirely outside the distal end portion 203, and may be configured such that only a part thereof is located outside the distal end portion 203.
[Method of manufacturing metal vapor discharge lamp]
A method for manufacturing the metal vapor discharge lamp 10 will be described below.

First, as shown in FIG. 6A, an inner tube 200 containing a discharge tube 100 and a base 500 are prepared, and a sealing portion 202 of the inner tube 200 and a portion of the base 500 on the discharge tube 100 side are prepared. After applying an adhesive (for example, an inorganic adhesive) to at least one, the two are joined. As a result, the inner tube 200 is attached to the base 500 as shown in FIG. Next, as shown in FIG. 6C, the protection member 300 is disposed in the outer tube 400. The method for inserting and arranging the protection member 300 in the outer tube 400 is as described above. Next, the outer tube 400 provided with the protective member 300 and the inner tube 200 to which the base 500 is attached are prepared, and at least the bonding portion 504 on the discharge tube 100 side of the base 500 and the opening 402 of the outer tube 400 are at least. After applying an adhesive (for example, an inorganic adhesive) on one side, the inner tube 200 is relatively inserted into the outer tube 400. The adhesive that fixes each of the inner tube 200 and the outer tube 400 to the base 500 has an abnormality in the inner tube 200 at the end of life, such as 200 [° C.], so as to withstand the heat generated when the metal vapor discharge lamp 10 is turned on. In view of safety during discharge, a heat resistance of 800 [° C.] is preferable. In addition, although the base 500 of the present embodiment shows an Edison base, it may be a swan type.
[Modification]
As described above, the metal vapor discharge lamp and the lighting device according to the present invention have been specifically described based on the embodiments. However, the metal vapor discharge lamp and the lighting device according to the present invention are not limited to the above embodiments. Needless to say.
[Modification 1]
FIG. 7 is a perspective view showing the shape of the protection member 310. In the protective member 310, four L-shaped claws 313 to 316 are extended from the regular octagonal plate-shaped portion 311 along the outer peripheral portion 312 of the plate-shaped portion 311 at equal intervals. In addition, you may fix these claws 313-316 by welding or caulking with respect to the outer peripheral part 312 of the plate-shaped part 311 what was manufactured separately from the plate-shaped part 311.
The plate-like portion 311 of the protection member 310 in Modification 1 is a regular octagonal shape, but the plate-like portion can be an elliptical shape or other polygonal shapes regardless of the disc shape or the regular octagonal shape. There is no restriction | limiting also about the shape of nail | claws 313-316, arrangement | positioning of each nail | claw, and it can select arbitrarily.
In addition, since the plate-like portion and the claw are formed of a single plate material because of the polygonal shape, if the claw is located on the side of the plate-like portion, the nail is compared with the embodiment shown in FIG. It is easy to bend and form.
[Modification 2]
FIG. 8 is a cross-sectional view showing the positional relationship between the outer tube 400, the protection member 320, and the inner tube 200 according to the second modification. As shown in the figure, protrusions 404 and 405 projecting inwardly in a radial direction are formed in a portion closer to the opening 402 than the endmost portion of the closing portion 401 of the outer tube 400.
The protection member 320 has a disk shape made of a material having elasticity, and is moved over the protrusions 404 and 405 by elastic deformation and fitted into the distal end portion of the outer tube 400, whereby the outer surface of the inner tube 200 and the outer tube 400 are The gap between the inner surface and the inner surface of the outer tube 400 can be arranged. As described above, a structure in which the protective member 320 is held by the protrusions 404 and 405 can be implemented. With this configuration, it is not necessary to fix the adhesive or the protective member by providing a claw, so that the material cost can be reduced and the workability at the time of manufacturing the lamp can be improved.
[Modification 3]
FIG. 9A is a cross-sectional view illustrating the positional relationship between the outer tube 400, the protection member 330, and the inner tube 200 according to the third modification. The closed portion of the outer tube 400 has a hemispherical shape.
FIG. 9B is a perspective view showing the shape of the protection member 330. As can be seen in the figure, the protective member 330 has a hemispherical shape and is made of an elastic material. In the third modification, the hemispherical protection member 330 is press-fitted into the distal end portion of the outer tube 400 and the inner surface of the outer tube 400 is pressed and fixed by a restoring force due to elasticity. Since the protective member 330 has a hemispherical space 331, the distance between the tip-off portion 201 of the inner tube 200 and the top of the protective member 330 can be increased. The speed reduction of the scattered fragments until the scattered fragments reach the protective member 330 is large, and a further explosion-proof effect can be expected.
[Modification 4]
FIG. 10A is a cross-sectional view showing the positional relationship among the outer tube 400, the protection member 340, and the inner tube 200 according to Modification 4. The protection member 340 is a combination of a plurality of metal wires 341... 342... In a mesh shape as shown in FIG. The protection member 340 is inserted into the distal end portion of the outer tube 400 and fixed to the inner wall of the outer tube 400 with an adhesive.

Since the protective member 340 has a mesh shape, the emitted light can leak from the gap between the metal wires 341 and 342, so that the luminance is hardly lowered in the lighting device. Furthermore, since the mass of the protective member is smaller than that of a plate-shaped metal, the lamp can be reduced in weight.
[Modification 5]
As a protective member, it is good also as a structure adhere | attached on the top part of the outer tube | pipe 400 with the adhesive agent 407 like the protective member 350 shown in FIG.

  With this configuration, the adhesive serves as a shock absorber, so that sufficient safety is ensured, and at the same time, the protective member 350 is fixed, so that the protective member 350 does not vibrate when the lamp is lit. Problems such as occurrence can be suppressed.

Moreover, it is also possible to arrange (apply) only the adhesive inside the outer tube blocking portion and serve as a protective member.
In addition, in FIG. 11, although the front-end | tip part of an outer tube | pipe is planar shape, when a protective member is similarly planar shape, since it is easy to ensure a contact area, improvement of the fixed workability | operativity with an adhesive agent is aimed at. Can do. However, the shape of the tip of the outer tube is not limited to a flat shape, and may be, for example, a hemispherical shape.
[Modification 6]
The shape of the protection member may be a cross shape like the protection member 360 shown in FIG.

With this configuration, compared to a disk-shaped one, the central portion is easy to be recessed and the shock is easily absorbed, so that sufficient safety can be ensured.
[Modification 7]
As shown in FIG. 13, the inner tube 200 may be fixed to the base 500 by holding the sealing portion 202 with a holder 12 provided in the base 500. The holder 12 is provided with an insertion port (not shown) that matches the shape of the sealing portion 202, and the sealing portion 202 is attached to the base 500 by inserting the tip of the sealing portion 202 into the insertion port. Fixed.

In this case, by fixing the sealing portion 202 to the holder 12 before fixing the holder 12 to the base 500, the sealing portion 202 is fixed and the second lead wires 126 and 127 of the inner pipe 200 are connected to the base 500. And the metal vapor discharge lamp 10 can be easily assembled. The holder 12 is provided with a bowl-shaped large-diameter portion 12 a on the outer peripheral surface thereof, and the large-diameter portion 12 a is engaged with the end portion 408 of the base 500 on the outer tube side. For example, the outer tube 400 may be fixed to the holder 12 by bringing the opening 402 of the outer tube 400 into contact with the side opposite to the base 500 of the large diameter portion 12a (the top side of the metal vapor discharge lamp 10). Good.
[Modification 8]
As shown in FIG. 14, the sealing portion 202 of the inner tube 200 is fixed to the base 500 in a state where it is also supported by the bowl-shaped member 13 disposed between the sealing portion 202 and the outer tube 400. May be. The bowl-shaped member 13 is a member for preventing the adhesive 11 from flowing to the discharge tube 100 side when the adhesive 11 is poured from the opening 402 side of the outer tube 400. It is fitted. A hole 13 a that matches the shape of the sealing portion 202 is formed in the approximate center of the bowl-shaped member 13. The shape of the hole 13a is substantially the same as the shape of the cross section when the sealing portion 202 is cut along a plane orthogonal to the lamp axis X, and the hook-like member 13 is press-fitted into the hole 13a. Further, the outer peripheral surface of the bowl-shaped member 13 is in contact with the inner surface of the outer tube 400. There is almost no gap between the flange-shaped member 13 and the sealing portion 202 and between the flange-shaped member 13 and the outer tube 400, so that the adhesive 11 does not leak from the gap.
[Modification 9]
As shown in FIG. 15, the sealing portion 202 of the inner tube 200 may be fixed to the base 500 in a state where the inner tube 200 is supported by the collar member 13 without using an adhesive. Further, the inner tube 200 may be fixed to the base 500 while being supported by an elastic metal member such as a clip (not shown) provided in the base 500. In these cases, the bonding step between the inner tube 200 and the outer tube 400 or between the inner tube 200 and the base 500 can be omitted.
[Others]
The protective member of the present invention is disposed on the outer tube in a state where a gap is provided between the protective member and the outer surface of the inner tube. Therefore, in addition to the embodiment and the modification, when the protection member is viewed in the tube axis direction from the closed portion side of the outer tube, the protection member can be formed so as to cover the inner tube tip. When this shape is adopted, even when the inner tube is damaged due to breakage of the discharge tube and a part of the inner tube is scattered, the fragments remain in the protective member. As a result, it is possible to prevent the outer tube tip from being damaged.

  In addition, about the shape of the protection member, the shape of an outer tube | pipe, and the adhering method which are described in each modification, it is not limited for every modification, Each combination can be selected suitably.

  INDUSTRIAL APPLICABILITY The present invention can be used for a metal vapor discharge lamp having a discharge tube, an inner tube, and an outer tube, particularly a low-wattage and compact triple-tube structure with power consumption of 100 W or less.

DESCRIPTION OF SYMBOLS 1 Illuminating device 10 Metal vapor discharge lamp 100 Discharge tube 200 Inner tube 203 Tip part 300 Protection member 400 Outer tube 401 Closure part 402 Opening part 500 Base

Claims (8)

An outer tube having an opening at one end and a closing portion at the other end;
A base attached to the opening of the outer tube;
An inner tube that is disposed in the outer tube and is attached so that a tip portion that is the other end is positioned on the closed portion side, with a sealing portion formed at one end fixed to the base.
A discharge tube housed in the inner tube;
A protective member disposed at least partially inside the outer tube and outside the tip of the inner tube, in a state where a gap is provided between the outer tube and the inner surface of the outer tube. ,
A metal vapor discharge lamp comprising: 2. The metal vapor discharge lamp according to claim 1, wherein all of the protection members are located inside the outer tube and outside a tip portion of the inner tube. The protective member has at least a part of elasticity, is disposed in the outer pipe in a state where the part is elastically deformed, and is attached to the inner surface of the outer pipe by a pressing force by the part. The metal vapor discharge lamp according to claim 1. The metal vapor discharge lamp according to claim 1, wherein the protective member is fixed to an inner surface of the outer tube with an adhesive. 2. The metal vapor according to claim 1, wherein a part of the protective member is fixed to an inner surface of the outer pipe by engaging a part of the protective member with an engaging portion provided inside the outer pipe. Discharge lamp. 2. The metal vapor discharge lamp according to claim 1, wherein the protection member is formed so as to cover a distal end portion of the inner tube when viewed in the tube axis direction from the closed portion side of the outer tube. 2. The metal vapor discharge lamp according to claim 1, wherein the protective member is made of a material having a heat resistance of 200 ° C. 3. The metal vapor discharge lamp according to claim 1, wherein the protective member is made of an elastic material.

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