JP5447970B2 - Lamp with fall prevention mechanism - Google Patents

Description

  The present invention relates to a lamp with a tube fall prevention mechanism.

  For example, high-intensity discharge lamps (HID lamps) such as high-pressure mercury lamps, metal halide lamps, ceramic metal halide lamps, and high-pressure sodium lamps emit light using discharge between electrodes. For this reason, compared with incandescent light bulbs, it has various features such as a large luminous flux suitable for lighting in a large-scale space, high energy efficiency, low power consumption, long life, and generally high color rendering. Therefore, it is generally used widely as lighting for stores, factories, halls, sports facilities, etc., location lighting for televisions and movies, and headlights for automobiles and railway vehicles.

  The high-intensity discharge lamp has a double structure in which an arc tube in which a discharge electrode and a discharge medium such as a metal halide or a rare gas are sealed as a light source is contained inside a tube (also referred to as an “outer bulb”). It has become. The stem tube of the mount that supports the arc tube and the neck portion of the outer tube bulb are sealed, and the inside of the outer tube bulb is made an inert gas, nitrogen gas, or vacuum atmosphere to protect the arc tube, keep the heat, and the outer bulb. It is intended to prevent oxidation of internal metal parts.

Japanese Unexamined Patent Publication No. 2002-184359 “Lighting Tube” (Released on June 28, 2002) Japanese Patent Laid-Open No. 2008-66222, “High Pressure Discharge Lamp” (published on Mar. 21, 2008) FIG. 1 is a diagram for explaining a tube drop prevention mechanism disclosed in Patent Document 1. However, in order to avoid duplication with the reference numerals in the drawings of the present application, the reference numerals in FIG. 1 and the following description have changed the reference numerals in FIGS. In the description paragraphs 0010 to 0011, “... the clasp 101 is composed of a clasp main body 101a and a clasp mandrel 101b, and the clasp main body 101a is a stainless steel plate folded so that the cross-section becomes a U-shape. Rotate around the clasp mandrel 101b.The range of rotation is up to 60 degrees with the support bracket .... The clasp body 1a is supported by the clasp mandrel 1b with the center of gravity axis removed. So, when the base is up, the clasp body rotates by gravity and the angle between the clasp and the support bracket 2 is rotated up to 60 degrees .... Conversely, when the base is down, the clasp The angle between the main body and the support bracket 2 is 0 degree. ”

FIG. 2 is a diagram illustrating a tube fall prevention mechanism disclosed in Patent Document 2. As shown in FIG. However, in order to avoid duplication with reference numerals in the drawings of the present application, the reference numerals in FIG. 2 are changed from the reference numerals in FIG. In summary, “In the lamp 210, the inner stem lead 212 in the sphere 214a of the outer tube bulb 214 has only one drop stopper 220 having an arm 222, and the arm 222 has one end as a fulcrum. As F, the other end is configured to freely rotate in a state in which an arc is drawn between the first position and the second position, and in the second position, the arm 222 has a tube axis Ax _{10 of the} outer tube valve 214. On the other hand, the angle is larger than 70 [°] and equal to or smaller than 110 [°]. "

  Patent Documents 1 and 2 do not disclose a tube drop prevention mechanism using a slide mechanism described below.

  High-intensity discharge lamps rarely cause cracks such as cracks in the sealing part of the stem tube and the neck part of the outer bulb when the cap is attached to the socket of the lighting device or during the lighting process. It sometimes occurred. The cause of the crack is that when the sealing part is molded due to a problem of glass melting by the heating burner during the sealing operation of the glass outer tube valve and the stem tube, The case where thickness becomes non-uniform | heterogenous is mentioned. Alternatively, the outer lead-in wire led out from the valve and the base are connected using a soldering material such as solder. In some cases, strain remains. Due to such non-uniformity of glass thickness, residual strain, and the like, minute scratches and cracks progress in the sealed portion of the outer tube valve and its peripheral portion, and the processing residual strain increases.

  When installing the E (screw-in) type cap of a high-intensity discharge lamp while screwing it into the socket, there is a strong twisting force on the sealing part of the outer tube bulb and its peripheral part, thermal shock or vibration shock due to lamp flashing, etc. When a minute scratch or crack, a portion with a large amount of strain, or the like is added, there is a risk that a crack or crack may occur in this portion.

  If a crack or a crack generated in the sealing portion or its peripheral portion makes a round, the outer tube valve may be detached from the E-type base and fall. This problem is not limited to the high-intensity discharge lamp as will be described later, but also exists in other incandescent lamps.

  In view of the above problems, an object of the present invention is to provide a lamp with a fall prevention mechanism that reliably prevents the fall of the tube even if a crack occurs in the sealed portion of the bulb and its peripheral portion. To do.

  In view of the above-described object, a lamp with a tube fall prevention mechanism according to the present invention includes a tube bulb having a larger diameter at the center than the bore of the neck, and the fall prevention mechanism of the tube, and the fall prevention mechanism. Has a slide member that is slidably held with respect to the mount, and the slide member is centered on a direction component along a lamp axis connecting the lamp cap and the top portion of the tube and the lamp axis. The slide member is slidable in a direction having a radial component, and when the lamp base is lowered, the slide member has a directional component from the top portion of the tube toward the lamp base along the lamp axis. The slide member slides in a direction having a radially inward component from the lamp axis, and the slide member stops within the range of the neck portion diameter, and the lamp is turned upside down to bring the lamp base upward. Then, the slide member slides in a direction having a direction component from the lamp cap toward the top portion of the tube and a radially outward component from the lamp axis along the lamp axis. A part of the member stops at a position exceeding the neck diameter.

  Further, in the lamp with the tube fall prevention mechanism, the slide member has a slide portion, a holding member that slidably holds the slide portion, and a fixing member that fixes the holding member to the mount. May be.

  Furthermore, in the lamp with the tube fall prevention mechanism, the slide member is formed by bending a wire rod into a substantially right triangle and connecting both ends, and the first side of the triangle is perpendicular to the lamp axis. The second side of the triangle may constitute a slide part, and the third side of the triangle may connect the end of the first side and the end of the second side.

  Furthermore, in the lamp with the tube fall prevention mechanism, the fall prevention mechanism further includes a turning prevention mechanism for the slide member, and the turning prevention mechanism is configured such that the slide member is arranged around an axis center of the slide portion. May be formed so as to surround the third side of the triangle.

  Further, in the lamp with the tube fall prevention mechanism, the fall prevention mechanism has a non-circular cross-sectional shape of the slide portion, and a cross-sectional shape of a holding member that slidably holds the slide portion corresponds to the non-circular shape. It may be configured as a non-annular shape.

  Furthermore, in the lamp with a tube fall prevention mechanism, the slide member may have a weight for increasing the weight.

  Furthermore, in the lamp with a tube fall prevention mechanism, a plurality of the fall prevention mechanisms may be provided.

  ADVANTAGE OF THE INVENTION According to this invention, even if a crack generate | occur | produces in the sealing part of a bulb | ball, and its peripheral part, the lamp | ramp with a fall prevention mechanism which prevents the fall of a bulb | ball can be provided reliably.

FIG. 1 is a diagram for explaining a tube drop prevention mechanism disclosed in Patent Document 1 which is a prior art document. FIG. 2 is a diagram for explaining a tube drop prevention mechanism disclosed in Patent Document 2 which is a prior art document. FIG. 3 is a diagram illustrating the entire high-intensity discharge lamp with a tube fall prevention mechanism according to the present embodiment. FIG. 4 is a view for explaining the bulb shape of the high-intensity discharge lamp according to the present embodiment. FIG. 5A shows the mount of FIG. 3 and the fall prevention mechanism for the tube attached thereto, where (A) shows the situation before the fall prevention mechanism is activated, and (B) is the situation after the actuation. Is shown. FIG. 5B is a diagram for explaining the details of the fall prevention mechanism of FIG. 5A. Here, (A) and (B) are enlarged views of the respective fall prevention mechanisms shown in (A) and (B) of FIG. 5A. FIG. FIG. 5C is a diagram for explaining the state before and after the operation of the slide member in FIG. 5A and the positional relationship between the slide member and the outer tube valve. FIG. 6 is a diagram for explaining how to use the high-intensity discharge lamp with a tube fall prevention mechanism shown in FIG. FIG. 7 is a diagram for explaining a high-intensity discharge lamp according to another embodiment having a plurality of tube drop prevention mechanisms.

  Hereinafter, embodiments of a lamp with a tube fall prevention mechanism according to the present invention will be described in detail with reference to the accompanying drawings. In the figure, the same reference numerals are assigned to the same elements, and duplicate descriptions are omitted.

[Lamp with tube fall prevention mechanism]
(Structure of high-intensity discharge lamp)
FIG. 3 is a diagram illustrating a lamp with a tube fall prevention mechanism according to the present embodiment. As a lamp, a ceramic metal halide lamp 10 which is one of high-intensity discharge lamps will be described as an example.

  As shown in FIG. 3, the lamp 10 has a double structure in which a light-emitting tube 4 serving as a light-emitting portion is enclosed inside a bulb (also referred to as “outer bulb”) 2. An E-shaped (screw-in) base 6 is joined to the end of the outer tube valve 2. The arc tube 4 is supported at a predetermined position and supplied with power by a mount 8 in which a shroud and a starting circuit (described later) are attached to a structure in which metal wires and plates are combined.

  Each of these elements will be described in detail.

  The arc tube 4 serving as a light emitting part is a translucent container made of ceramics having the shape of a central thick tube part 4a and thin tube parts 4b, 4c at both ends. A pair of lead wires 5 and 7 extend through the thin tube portions 4b and 4c to the region of the thick tube portion 4a to form a pair of main electrodes (not shown). These electrodes are typically made of tungsten (W) or the like.

  The container of the arc tube 4 is filled with a predetermined amount of mercury, a metal halide, and an argon (Ar) gas having a predetermined pressure as a rare gas as light emission and discharge media. As the rare gas, in addition to the argon (Ar) gas, a small amount of other rare gas such as neon (Ne) may be mixed. Examples of the metal halide include halogens such as iodine (I), bromine (Br), and chlorine (Cl), and at least sodium (Na), scandium (Sc), cesium (Cs), dysprosium (Dy), and the like. A kind of light-emitting metal is enclosed, and characteristics such as luminous efficiency, color rendering properties, and color temperature are improved.

  The mount 8 includes a stem tube 14 hermetically sealed with a pair of lead wires, a wire rod such as molybdenum Mo and stainless steel connected to one lead wire, and a round bar formed into a substantially long rectangular frame shape. A starting circuit comprising a support column 16, a shroud (also referred to as “middle tube”) 18 made of a transparent quartz glass tube disposed so as to surround the arc tube 4, and a thermally responsive switch such as a resistor or a bimetal. The part 20 is configured as a main part.

  The outer bulb 2 is made of translucent hard glass such as borosilicate glass, for example, and has a central portion 2a having a maximum aperture, a closed top portion 2b on the lower side as viewed in the drawing, and an upper neck portion 2c. BT shape having The neck portion 2c has a sealing portion (not shown) in which the flared portion of the stem tube 14 is sealed. After sealing, the neck portion 2c is removed through an exhaust pipe (not shown) provided in the stem tube 14. The tube valve 2 is evacuated and filled with an inert gas such as argon (Ar), nitrogen (N2) gas, or the like, or in a vacuum-tight air atmosphere. The screw-type base 6 is joined using a heat-resistant adhesive so as to cover the sealing portion, or the base 6 is screwed into a spiral thread groove formed by a mold.

  The fall prevention mechanism 22 will be described later with reference to FIGS. 5A, 5B and 5C.

  The ceramic metal halide lamp 10 shown in FIG. 3 is lit in a vertically or inclined base-up state in which the base 6 side is positioned upward. That is, the ceramic metal halide lamp 10 is mounted in a socket (not shown), energized from a power source through a predetermined lighting circuit device (not shown), and stable lighting is sustained by discharge between main electrodes. .

(Target lamp and lamp shape)
In FIG. 3, the ceramic metal halide lamp 10 is described as an example. However, it is not limited to this. Target lamps include high-intensity discharge lamps such as high-pressure mercury lamps, metal halide lamps, self-ballast mercury lamps and high-pressure sodium lamps. Further, the target lamp is not limited to a high-intensity discharge lamp, and includes an incandescent lamp or the like in which a tube is exposed and used without a cover.

  In FIG. 3, the BT lamp 10 is described as an example. However, the shape of the lamp is not limited to this. FIG. 4 is a diagram illustrating the bulb shape of the lamp according to the present embodiment. The lamp according to the present embodiment may have all lamp shapes in which the central portion 2a has a larger diameter than the neck portion 2c. For example, the lamp according to the present embodiment includes B type (Bulged) shown in (A), BT type (Bulged-Tube) shown in (B), R type (Reflector) shown in (C), and (D). It may be G type (Globe) shown. However, the T (Tube) type shown in (E) in which the neck portion 2c and the central portion 2a have the same diameter is not an object of this embodiment.

(Tube drop prevention mechanism)
5A, 5B and 5C are diagrams for explaining the details of the tube drop prevention mechanism 22 of the high-intensity discharge lamp shown in FIG.

  FIG. 5A shows the mount 8 of FIG. 3 and the tube drop prevention mechanism 22 attached thereto, where (A) shows the situation before the fall prevention mechanism 22 is activated, and (B) is activated. The latter situation is shown. It should be noted here that in FIG. 5A, the mount 8 is drawn so as to correspond to (A) and (B) in order to make it easy to understand the operating state of the fall prevention mechanism 22 with respect to the mount 8. That is, the gravity G with respect to the mount 8 and the fall prevention mechanism 22 is applied in the direction of the arrow (upward in the drawing) in FIG. Note that the direction is reversed (downward in the drawing).

  The fall prevention mechanism 22 is attached to a predetermined location (the support column 16 in the figure) of the mount 8. The fall prevention mechanism 22 is preferably attached at a position where the influence on the light distribution from the arc tube is small. The fall prevention mechanism 22 is preferably formed of a wire material such as molybdenum Mo or stainless steel, which is the same material as the support column 16. The operation of the fall prevention mechanism 22 is performed by turning the high-intensity discharge lamp 10 upside down (thus turning the inside fall prevention mechanism 22 upside down).

  By turning the mount 8 shown in (A) upside down, the fall prevention mechanism 22 moves from the mount 8 in the horizontal direction (open arrow) as shown in (B).

  FIG. 5B is a diagram for explaining the details of the fall prevention mechanism 22. Here, (A) and (B) of FIG. 5B are respective fall prevention mechanisms shown in (A) and (B) of FIG. 5A. 22 is an enlarged view of FIG. As shown in FIG. 5A, the fall prevention mechanism 22 has a slide member 22c, a holding member 22a for holding the slide member 22c, and the holding member fixed to a part of the mount (the column 16 in the figure). And a rotation preventing member 22d for preventing the sliding member 22c from turning.

  The slide member 22c is formed by bending a wire or rod-like body (hereinafter simply referred to as “wire”) having a predetermined length into a substantially triangular shape and connecting both ends.

  The holding member 22a is constituted by a cylindrical member (tube shape) having a predetermined length formed so as to surround a part of the slide portion 22c-1 corresponding to one side of the triangular slide member 22c. Hold it slidable.

  The fixing member 22b fixes the holding member 22a to a part of the mount 8 (in the figure, the support column 16).

  The fall prevention mechanism 22 includes a slide member 22c that is slidably held with respect to the mount 8. In the completed state of the lamp, the slide member 22c includes the lamp base 6 and the top portion 2b of the tube 2. Are slidable in a direction having a directional component along the lamp axis LL ′ and a radial component centered on the lamp axis.

  The turning prevention member 22d prevents the slide member 22c from turning with respect to the holding member 22a. The rotation prevention member 22d is a U-shaped wire attached to the support column 16, and ensures free sliding movement of the slide member 22c and prevents the slide member 22c from turning. That is, by surrounding the side 22c-2, the slide member 22c is prevented from turning around the axial center of the slide portion 22c-1.

  Regarding the operating state of the fall prevention mechanism 22, as shown in (A), most of the slide member 22 c is initially located inside the mount 8 (that is, the right side of the column 16). When the lamp 10 is turned upside down from this state (that is, the mount 8 and the slide member 22c are turned upside down), as shown in (B), the slide member 22c moves in the horizontal direction as shown by the white arrow. .

  FIG. 5C is a view for explaining the state of the slide member 22c before and after operation and the positional relationship between the slide member and the outer tube valve 2. The slide member 22c before operation is indicated by a broken line, and the slide member 22c after operation is indicated by a solid line.

  Before the operation, the slide member 22c is stopped at a position away from the inner surface of the neck portion 2c of the outer pipe valve 2. By reversing the upper limit of the mount 8 and the slide member 22c, the direction in which the gravity G is applied is reversed, and the slide portion 22c-1 slides (slides) with respect to the holding member 22b by the weight of the slide member 22c. The slide member 22c moves obliquely downward (in the direction of the white arrow) as a whole.

  The slide member 22c stops at a position longer than the neck portion 2c (that is, outside the neck portion) at a distance from the axial center of the outer tube valve 2. Alternatively, the slide member 22c is engaged with an engaging portion 2d having a larger diameter than the neck portion 2c of the outer tube valve 2 (specifically, a transition portion from the neck portion 2c to the central portion 2a, or the central portion 2a). . In order to perform this sliding movement smoothly, it is preferable that the surface of the slide part 22c-1 is well polished.

  Most of the slide member 22c drawn with a broken line before operation was positioned on the right side (that is, inside the mount 8) from the support column 16. Therefore, it is possible to insert the mount 8 through the neck portion 2a having a narrow diameter of the outer tube valve 2. After the upside down operation, most of the slide member 22c is positioned on the left side of the column 16 (that is, outside the mount 8) and is stopped. Therefore, even if the mount 8 is to be pulled out from the neck portion 2c having a small diameter of the outer tube valve 2, the slide member 22c is engaged with the inner surface of the outer tube valve 2 and cannot be pulled out. That is, the mount 8 formed integrally with the base 6 screwed into the socket (not shown) and the outer tube valve 2 cannot be separated.

  Although the attachment direction of the lamp 10 has been described so far as attaching to the socket (not shown) with the cap 6 facing upward, the present invention is not limited to this. It should be understood that the fall prevention mechanism 22 functions if the slide movement direction (the direction of the white arrow) of the slide member 22c is downward from the horizontal direction. Even if the axis LL ′ (see FIG. 3) of the lamp 10 is oblique in the lighting state, the fall prevention mechanism 22 functions as long as the slide movement direction is downward from the horizontal direction. When the lamp 10 is mounted obliquely and lit, it is preferable that the slide member 22c is reliably slid and moved in advance by giving a slight vibration.

  Here, the slide member 22c is formed by bending the wire rod into a substantially right triangle (however, the right angle portion may be a little acute) and connecting both ends. First, when the slide member 22c is held by the holding member 22a, the side 22c-2 extends in the vertical direction along the axis LL ′ of the outer tube valve 2, so that the slide member 22c is moved before operation. It can be stored in the innermost side (a position short in the radial direction from the axis of the outer tube valve 2).

  Next, the length of the slide part 22c-1 can be ensured long.

  Furthermore, this is due to a combination of a request for smooth slide movement and a request for large lateral movement of the slide member 22c (movement in the radial direction from the axis of the outer tube valve 2). That is, if the inclination θ of the slide portion 22c-1 with respect to the support column 16 is small, the slide movement is performed smoothly. However, the lateral movement distance of the slide member 22c is reduced. On the other hand, when this inclination θ is increased, the lateral movement distance of the slide member 22c is increased, but the smooth sliding movement of the slide portion 22c-1 is lacking.

  Eventually, the side 22c-2 extending vertically is determined first. Next, an inclination θ that can ensure a smooth slide movement through an experiment is determined. At present, this inclination θ is around 45 degrees. Furthermore, when the lateral movement distance (distance in the radial direction from the axis LL ′) of the slide member 22c that reliably exhibits the fall prevention function is determined, the slidable length of the slide portion 22c-1 (ie , The length of the slide portion 22c-1 and the length of the holding member 22a) are determined. Finally, the length of the other side is inevitably determined.

  As a shape satisfying these various requirements, the slide member 22c is formed by bending the wire material into a substantially right triangle (the right angle portion may be slightly acute) and connecting both ends.

(Modification of mount and slide member)
Here, with reference to FIGS. 5A to 5C, modifications related to the mount 8 (in particular, the support column 16) and the slide member 22 c will be listed.

  (1) The slide member 22c is not limited to a wire shaped into a triangle. Other shapes may be adopted as long as the slide portion 22c-1 is a straight wire having a predetermined length. For example, the portion excluding the slide portion 22c-1 may be a triangular plate. Or 22c-2 which is one side of a triangle may not be a continuous wire, but may have a notch in part.

  (2) The turning prevention member 22d is shown as a U-shaped wire attached to the support column 16, but is not limited thereto. For example, as described in the above (1), when the slide member 22c is a triangular plate-like body, the turning prevention member 22d is an L-shaped wire attached to the support column 16.

  (3) Although the rotation preventing member 22d is shown as a separate body from the slide member 22c, it is not limited to this. This turning occurs because the cross-sectional shape of the slide portion 22c-1 is circular. Therefore, other turning prevention mechanisms may be employed. For example, as a turning prevention mechanism, the cross-sectional shape of the slide portion 22c-1 may be a non-circular shape, and the cross-sectional shape of the holding member 22a may be a non-circular shape surrounding the same. Specifically, the cross-sectional shape of the slide portion 22c-1 may be an elliptical or polygonal (triangle, quadrangle, etc.) wire, and the holding member 22a may be an elliptical tube or a polygonal tube corresponding thereto.

  (4) The slide movement of the slide member 22c is operated using gravity. Therefore, the sliding movement is performed smoothly by increasing the weight of the sliding member 22c. Therefore, the weight may be increased by forming the slide member 22c from a heavy metal, attaching a weight to a part of the slide member 22c, or thickening a part of the slide member 22c. For example, one or both portions at both ends of the slide portion 22c-1 may be formed into a ball shape to form a weight portion.

  (5) The target to which the slide member 22c is fixed is not limited to the support column 16. You may fix to the desired location of the mount 8 integrated with the nozzle | cap | die 6.

(Use state)
FIG. 6 is a diagram for explaining how to use the high-intensity discharge lamp 10 shown in FIG. In (A), the slide member 22 c is attached to the mount 8. Next, in (B), the outer tube valve 2 is positioned with the neck portion 2c facing down. Next, the mount 8 is inserted into the outer tube valve 2 from below through the neck portion 2c. At this time, as shown in (C), most of the slide member 22c attached to the mount 8 is located in the mount 8 and can be easily inserted. At the stage of (D) when the insertion is completed, the base 6 is prepared and attached to the neck portion 2c. Next, at the stage (E), the ramp 2 is turned upside down to slide the slide member 22c. At the stage where this slide movement is completed, most of the slide member 22 c is stopped at a position outside the mount 8.

  In the completed state of the lamp, when the lamp cap 6 is moved downward, the slide member 22c moves in the radial direction from the lamp axis and the direction component from the top 2b of the tube toward the lamp cap 6 along the lamp axis LL '. The slide member 22c slides in a direction having a direction component and stops within the range of the diameter of the neck portion 2c. When the lamp 10 is turned upside down and the lamp cap 6 is turned upward, the slide member 22c has a directional component from the lamp cap 6 toward the top portion 2b of the tube along the lamp axis LL 'and a radial direction from the lamp axis. The slide member 22c slides in a direction having an outward component and stops at a position exceeding the diameter of the neck portion 2c.

  As a result, even if the sealing part of the outer pipe valve 2 or a peripheral part thereof is cracked or cracked and tries to fall around, the slide member 22c engages with a part of the inner wall of the outer pipe valve 2 and The pipe valve 2 is not detached from the base 6 and falls.

  At this time, if a slight vibration is applied to the lamp 10, the slide member 22c slides more reliably. Actually, when the lamp user screws the base 6 of the lamp 10 from below into a socket (not shown) attached to the ceiling or other place, a slight vibration is applied to the lamp 10 and the slide is slid. The member 22c surely slides.

[Lamp with tube fall prevention mechanism according to another embodiment]
FIG. 7 is a view for explaining a lamp according to another embodiment having a plurality (two in the figure) of tube drop prevention mechanisms 22. As shown in FIG. 4, the outer bulb 2 of the lamp 10 has various shapes. For example, in the case of a valve shape in which the diameter gradually increases from the neck portion 2c to the central portion 2a, it is preferable to provide a plurality of fall prevention mechanisms 22-1 and 22-2. The number of fall prevention mechanisms 22 is determined by the shape of the outer bulb 2 of each lamp, the positional relationship between the outer bulb 2 and the mount 8, and the like.

[Others]
The embodiment of the lamp with the tube drop prevention mechanism has been described above, but these are examples, and the present invention is not limited to this. Additions, deletions, modifications, improvements, and the like to the embodiments that can be easily made by those skilled in the art are within the scope of the present invention. The technical scope of the present invention is defined based on the description of the appended claims.

  10: Ceramic metal halide lamp, lamp, BT type lamp, 2: Tube, outer bulb, 2a: Center portion, 2b: Top portion, 2c: Neck portion, 4: Arc tube, 4a: Thick tube portion, 4b, 4c : Thin tube part, 5: lead wire, 6: cap, 7: lead wire, 8: mount, 12: metal foil, 14: stem tube, 16: support, 18: shroud, middle tube, 20: starting circuit, 22: Fall prevention mechanism, 22a: holding member, 22b: fixing member, 22c: slide member, 22c-1: slide part, 22c-2: one side, 22d: rotation prevention member,

Claims (7)

A tube having a larger diameter in the center than the diameter of the neck,
In the lamp with a tube fall prevention mechanism provided with the tube fall prevention mechanism ,
The fall prevention mechanism has a slide member that is slidably held with respect to the mount,
The slide member is slidable in a direction having a directional component along a lamp axis connecting the lamp base and the top portion of the tube and a radial component centered on the lamp axis,
When the lamp base is lowered, the slide member slides in a direction having a direction component from the top portion of the bulb toward the lamp base and a radial inward component from the lamp axis along the lamp axis. The slide member stops within the range of the neck portion caliber,
When the lamp is turned upside down and the lamp cap is turned upward, the slide member has a direction component from the lamp cap toward the top of the tube along the lamp axis and a radially outward component from the lamp axis. A lamp with a tube fall prevention mechanism, in which a part of the slide member stops at a position exceeding the neck diameter. The lamp of claim 1, wherein
The fall prevention mechanism is
And the slide member,
A holding member for slidably holding the slide part;
And a fixing member for fixing the holding member to the mount. The lamp according to claim 2, wherein
The slide member is formed by connecting both ends by bending a wire rod into a substantially right triangle,
A first side of the triangle extends vertically along the ramp axis;
The second side of the triangle constitutes the slide part,
The third side of the triangle is a lamp that connects the end of the first side and the end of the second side. The lamp according to claim 3,
The fall prevention mechanism further includes a turning prevention mechanism for the slide member,
The swivel prevention mechanism is a ramp formed so as to surround the third side of the triangle so that the slide member does not swivel around the axis center of the slide portion. The lamp according to claim 3,
The fall prevention mechanism is configured such that a cross-sectional shape of the slide portion is non-circular, and a cross-sectional shape of a holding member that slidably holds the slide portion is a non-annular shape corresponding to the non-circular shape. . The lamp according to claim 2, wherein
The slide member has a weight for increasing the weight, the lamp. The lamp of claim 1, wherein
A lamp provided with a plurality of the fall prevention mechanisms.

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