JP2013134323A - Stroboscopic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use a concave mirror as the trigger electrode of a xenon discharge tube by improving the heat resistance of a lamp holder, thereby making the number of continuous light emittable times larger and solving the problem of thermal damage of the lamp holder.SOLUTION: A lamp holder 30 comprises a ceramic molding.

Description

  The present invention relates to a strobe device, and more particularly to a strobe device for a camera having a zoom function.

  As a strobe device for a camera, a lamp holder holding a light emitting means such as a xenon discharge tube in a housing is provided so as to be movable in the front-rear direction, and the Fresnel disposed in front of the lamp holder by moving the lamp holder in the front-rear direction There is known a strobe device having a zoom function in which an irradiation angle (strobe irradiation angle) of a strobe light with respect to a subject is changed by changing a distance in the optical axis direction between the lens and the light emitting means (for example, Patent Document 1).

JP 2003-84340 A

  Since the lamp holder of the conventional strobe device is a molded product made of synthetic resin such as polyacrylate, when the light emitting means such as a xenon discharge tube emits light repeatedly with a short interval of several seconds (hereinafter referred to as continuous light emission). The lamp holder undergoes thermal damage such as deformation due to the temperature rise of the light emitting means due to continuous light emission of several tens of times (several minutes). On the other hand, in a conventional strobe device, the number of continuous light emission is limited to several tens of times or less by a protect circuit. This makes it impossible to perform strobe shooting under severe conditions such as occupational shooting that requires continuous light emission over several tens of minutes.

  When the xenon discharge tube comes into contact with the metal concave mirror attached to the lamp holder and the concave mirror also serves as the trigger electrode of the xenon discharge tube, the temperature rise of the lamp holder is caused by the heat transfer by conduction and the concave mirror and the lamp. The temperature rise of the holder is severe, and the lamp holder is more likely to be thermally damaged.

  The problem to be solved by the present invention is to improve the heat resistance of the lamp holder and increase the number of times that continuous light emission is possible, and at the same time, the concave mirror can be triggered by the xenon discharge tube without causing the heat damage problem of the lamp holder. It is to make an electrode.

  The strobe device according to the present invention includes a box-shaped housing (18) having a front opening, a Fresnel lens (24) attached to a front portion of the housing (18), and the housing (18) attached to the housing (18). ) Is engaged with the guide bar (26) extending in the front-rear direction, and is guided by the guide bar (26) and is movable in the front-rear direction within the housing (18). A lamp holder (30) having a front opening, a light emitting means (40) provided in the lamp holder (30), and a light attached to the lamp holder (30) and emitted by the light emitting means (40) in the housing A concave mirror (42) that reflects to the front opening side of (18) and emits light forward from the front opening; and the lamp holder (30) is a ceramic molded article.

  According to the stroboscopic device of the present invention, the ceramic lamp holder (30) is heat resistant as compared with the one made of synthetic resin, so that the lamp holder (30) is heated by the heat generated by the light emitting means (40) by continuous light emission. Even if the temperature rises, the lamp holder (30) does not cause thermal damage such as deformation and scorching.

  In the strobe device according to the present invention, preferably, the light emitting means is constituted by a xenon discharge tube (40), the concave mirror (42) is constituted by a conductive material, and the trigger electrode of the xenon discharge tube (40) is formed. Yes.

  According to this configuration, the concave mirror (42) acts as a trigger electrode extending over the entire axial length of the xenon discharge tube (40), so that the discharge of the xenon discharge tube (40) is stably performed. . When the concave mirror (42) is a trigger electrode, the temperature rise of the concave mirror (42) in continuous light emission becomes more severe than in the case where it is not so, and the heat load of the lamp holder (30) increases, but the lamp holder (30) Is not made of ceramics, causing thermal problems.

  In the strobe device according to the present invention, the guide bar (26) is preferably made of a non-conductive material, more preferably a molded product made of ceramics.

  According to this configuration, even when the concave mirror (42) functioning as the trigger electrode and the guide bar (26) are adjacent to each other, no short circuit discharge occurs between the concave mirror (42) and the guide bar (26). In particular, when the guide bar (26) is made of ceramic, the lamp holder (30), which is the sliding partner, is also made of ceramic, so that the sliding surfaces of both are not worn at an early stage and are durable. There is no decline in sex.

  The strobe device according to the present invention preferably has a corrugated portion (44A) extending in the left-right direction along the back surface (30D) of the lamp holder (30) and the xenon at both ends of the corrugated portion (44A). A discharge tube fixture (44) made of a metal wire having a ring portion (44B) fitted to the outer periphery of the end portion of the discharge tube (40), and the xenon discharge tube ( 40) is fixed to the lamp holder (30) in a state where it is pressed against the concave mirror (42) at a portion located on the back side of the xenon discharge tube (40).

  According to this configuration, since the discharge tube fitting (44) is made of a metal wire and does not cause thermal damage or deterioration, the xenon discharge tube (40) is held at a high temperature by the discharge tube fitting (44). It is stable and durable even in the atmosphere.

  In the strobe device according to the present invention, preferably, the ring portion (44B) of the discharge tube fixture (44) forms another trigger electrode of the xenon discharge tube (40).

  According to this configuration, since the ring portion (44B) of the discharge tube fixture (44) forms another trigger electrode of the xenon discharge tube (40), the discharge of the xenon discharge tube (40) is further stabilized. Will be done.

  In the strobe device according to the present invention, preferably, the Fresnel lens is made of glass. Since the Fresnel lens is made of glass, even if continuous light emission is performed, yellowing or displacement due to heat burn that occurs in a plastic Fresnel lens does not occur.

  In the strobe device according to the present invention, since the lamp holder is made of ceramics, the lamp holder has excellent heat resistance, and the lamp holder is deformed even when the temperature of the lamp holder rises due to heat generated by the light emitting means due to continuous light emission. No heat damage such as scorching. As a result, the possible number of continuous light emission can be increased, and the concave mirror can be used as the trigger electrode of the xenon discharge tube without causing a thermal problem in the lamp holder.

The perspective view which shows the external appearance of one Embodiment of the strobe device by this invention. FIG. 3 is a half sectional perspective view of a main part of the strobe zoom device according to the present embodiment. FIG. 3 is a perspective view of the strobe zoom device according to the present embodiment. The perspective view which looked at the lamp holder used for the strobe zoom device by a present Example from the back. The perspective view of the discharge tube attachment used for the strobe zoom device by a present Example.

  One embodiment of a strobe device according to the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the strobe zoom device incorporates electric parts such as a battery, a capacitor, and a control board inside, and is mounted on a strobe mounting shoe of a camera body (not shown). And a light emitting part outer case 12 made of a synthetic resin with a bounce function attached to an upper part of the electrical part outer case 10 so as to be rotatable around a horizontal axis.

  The light emitting part outer case 12 is a box-shaped one having a rectangular front opening (light irradiation window) 14. The front opening 14 is closed by a rectangular front shield plate 16 made of a transparent acrylic resin and attached to the light emitting portion outer case 12.

  As shown in FIG. 2, a box-shaped housing 18 having a front opening and a lens support member 20 are attached in the light emitting portion outer case 12. Both the housing 18 and the lens support member 20 have high heat resistance comparable to metals, such as high heat resistant polyamide resin, high heat resistant epoxy resin, high heat resistant polyamide imide resin, and high heat resistant polyether ether ketone resin. This is a molded product of potassium titanate fiber reinforced plastic using a synthetic resin as a base material.

  The lens support member 20 is formed in a frame shape having a square Fresnel lens mounting opening 22 and is fixedly disposed between the front portion of the housing 18 and the front shield plate 16. A square Fresnel lens 24 made of heat-resistant glass is attached to the Fresnel lens mounting opening 22.

  As shown in FIG. 3, two guide bars 26 extending in the front-rear direction are attached to the housing 18 in parallel to each other. The guide bar 26 is a cylindrical molded product made of ceramics such as zirconia, and the front and rear end portions are fixed to the front wall portion 18A and the rear wall portion 18B of the housing 18.

  A lamp holder 30 is disposed in the housing 18. The lamp holder 30 is a molded product made of ceramics such as alumina, and has a rectangular box shape with a front opening. Two sleeve portions 30 </ b> A that are long in the front-rear direction are integrally formed at the lower portion of the lamp holder 30. Each of the sleeve portions 30A is slidably engaged with the guide bar 26. Thus, the lamp holder 30 can be guided in the guide bar 26 and translated in the front-rear direction in the housing 18.

  An electric motor 32 such as a servomotor is attached to the rear wall portion 18B of the housing 18. A base end portion of the feed screw rod 34 is directly connected to an output shaft (not shown) of the electric motor 32. The feed screw rod 34 is a round bar made of synthetic resin having high heat resistance comparable to metal, such as high heat resistant polyamide resin, high heat resistant epoxy resin, high heat resistant polyamide imide resin, high heat resistant polyether ether ketone resin, etc. A thread groove 34 </ b> A is machined on the outer circumference of the lamp holder 30. The lower part of the lamp holder 30 extends in the front-rear direction in parallel with the guide bar 26, and is directly rotated by the electric motor 32.

  A wire member 36 is attached to the lower bottom portion of the lamp holder 30. The wire member 36 has a spiral-shaped portion 36A that substantially wraps around the screw groove 34A as a portion that wraps around and engages with the screw groove 34A of the feed screw rod 34, and the central axis of the feed screw rod 34 from both ends of the spiral-shaped portion 36A. And a pair of left and right extension end line portions 36B extending in a direction perpendicular to the horizontal direction (left and right direction) and crossing the center of the spiral shaped portion 36A, and the entire thread groove 34A accompanying the rotation of the feed screw rod 34 In order to absorb the sliding sound between the spiral portion 36A and the spiral-shaped portion 36A, it is constituted by a spring wire having an appropriate elasticity. Examples of the spring wire suitable as the wire member 36 include wires made of spring steel, stainless steel, phosphor bronze and the like.

  The wire member 36 is fixed to the lamp holder 30 by fitting the left and right extended end line portions 36B between the engaging protrusion pairs 38 that are formed to protrude at the left and right positions of the lower bottom portion of the lamp holder 30. The extended end line portion 36B is sandwiched from the front and rear by the left and right engaging projection pairs 38, respectively.

  As described above, since the screw groove 34A of the feed screw rod 34 and the helically shaped portion 36A of the wire member 36 are substantially screw-engaged, the lamp holder 30 is driven by the rotation of the feed screw rod 34 by the electric motor 32. Moves back and forth (zoom movement).

  As shown in FIG. 2, a concave mirror 42 and a rod-shaped xenon discharge tube 40 are attached to the lamp holder 30. The concave mirror 42 is a press-formed product of a metal plate having a surface excellent in light reflectivity, such as an aluminum plate, a stainless steel plate, a plated steel plate, etc., and has a parabolic cross section and a rectangular light emission opening 42A on the front side. It has a bowl shape with The concave mirror 42 is fixed to the lamp holder 30 by engaging the upper and lower edges 42B and 42C of the light exit opening 42A with the upper and lower edges 30B and 30C of the front opening of the lamp holder 30.

  The xenon discharge tube 40 is a quartz tube, and is fixed to the lamp holder 30 by a discharge tube fitting 44 as shown in FIG. The discharge tube fixture 44 includes a corrugated portion 44A extending in the left-right direction along the back surface 30D of the lamp holder 30, and an end portion where the xenon discharge tube 40 protrudes laterally from the concave mirror 42 at both ends of the corrugated portion 44A. It has an annular portion 44B fitted to the outer periphery of 40A, and the whole is constituted by a metal wire having spring properties such as spring steel, stainless steel, phosphor bronze.

  As shown in FIG. 5, the discharge tube attachment 44 is in a direction in which the annular portions 44B on both sides open (expand) with respect to the extending direction of the corrugated portion 44A in the single product state before attachment. Inclined. The discharge tube attachment 44 is assembled to the back surface 30D of the lamp holder 30 and the end 40A of the xenon discharge tube 40 in a state in which the corrugated portion 44A and the annular portion 44B are elastically deformed in the direction in which the open leg is lost. Thus, the xenon discharge tube 40 is fixed to the lamp holder 30 while being pressed against the bottom 42D (see FIG. 2) of the concave mirror 42 located on the back side of the xenon discharge tube 40.

  Since the discharge tube fixture 44 is made of a metal wire and does not cause thermal damage or thermal deterioration, the xenon discharge tube 40 is held stably by the discharge tube fixture 44 even in a high temperature atmosphere with good durability. become. Since the corrugated portion 44A of the discharge tube fixture 44 undulates up and down along the back surface 30D of the lamp holder 30, it is the same as being in contact with the back surface 30D. It does not move in a direction that tilts up and down with respect to the holder 30. Accordingly, the attachment position of the xenon discharge tube 40 fitted in the annular portion 44B of the discharge tube attachment 44 does not change with respect to the lamp holder 30, and the xenon discharge tube 40 is attached to the light emitting portion outer case 12. Even if vibration or the like is applied, the concave mirror 42 is stably positioned at the position pressed against the bottom 42D.

  As shown in FIG. 4, the conductive connection between the discharge electrode (not shown) provided at the end 40A of the xenon discharge tube 40 and the discharge lead 46 is made of a copper sheath 48 having high heat resistance. It is done by caulking. A trigger electrode connection terminal 50 is integrally formed on the concave mirror 42. A trigger lead wire 52 is conductively connected to the trigger electrode connection terminal 50 by caulking with a copper sleeve or the like. As a result, the concave mirror 42 acts as a trigger electrode extending over the entire axial length of the xenon discharge tube 40, so that the discharge of the xenon discharge tube 40 is stably performed.

  On the outer periphery of one end portion 40A of the xenon discharge tube 40, an auxiliary trigger electrode 54 formed by forming an annular shape of a conductive paste such as a silver paste is formed. The auxiliary trigger electrode 54 is conductively connected to the trigger electrode connection terminal 50 by an auxiliary trigger lead wire 56. The auxiliary trigger lead wire 56 and the trigger electrode connection terminal 50 are also connected by caulking using a copper sleeve or the like. Further, since the auxiliary trigger electrode 54 is in contact with the annular portion 44B of the discharge tube fixture 44, the annular portion 44B also functions as an auxiliary trigger electrode. The discharge of the xenon discharge tube 40 is more stably performed by these auxiliary trigger electrodes.

  The strobe device according to the present embodiment has higher heat resistance than the lamp holder 30 made of synthetic resin because the lamp holder 30 is made of ceramics. For this reason, even if the temperature of the lamp holder 30 rises due to heat generated by the xenon discharge tube 40 due to continuous light emission, the lamp holder 30 will not be deformed or burnt or otherwise damaged by heat. As a result, a strobe device that can withstand severe use such as occupational photography that requires continuous light emission over several tens of minutes can be obtained.

  When the concave mirror 42 is used as a trigger electrode of the xenon discharge tube 40 and the concave mirror 42 is in contact with the xenon discharge tube 40, the heat of the xenon discharge tube 40 is transferred to the concave mirror 42 by conduction, and therefore the temperature of the concave mirror 42 in continuous light emission increases. Along with this, the heat load on the lamp holder 30 supporting the concave mirror 42 increases. However, since the lamp holder 30 is made of ceramic, the lamp holder 30 does not cause a thermal problem. This becomes remarkable in a large strobe device with a large calorific value of the xenon discharge tube 40, but even in such a strobe device, since the lamp holder 30 is made of ceramics, no thermal problem occurs. Durability can be ensured.

  For this reason, the concave mirror 42 can be used as an excellent trigger electrode of the xenon discharge tube 40 even in a large strobe device often used for professional photography, and the discharge of the xenon discharge tube 40 is stably performed. It becomes like this.

  If the concave mirror 42 is used as the trigger electrode of the xenon discharge tube 40, the lower edge portion 42C of the concave mirror 42 and the guide bar 26 and the feed screw rod 34 are adjacent to each other, which may cause a short-circuit discharge therebetween. On the other hand, the guide bar 26 is made of ceramics, and the feed screw rod 34 is a heat-resistant synthetic resin, both of which are non-conductors (electrical insulators). The fact that the guide bar 26 is made of ceramics means that the sleeve part 30A of the lamp holder 30 that is the sliding partner is also made of ceramics, so that both sliding surfaces do not wear out at an early stage and the durability is lowered. Will not occur.

  In the strobe device according to the present embodiment, since the Fresnel lens 24 is made of glass, the heat resistance is better than that made of plastic. Thereby, even if continuous light emission is performed, the Fresnel lens 24 does not cause yellowing or deformation due to heat burn.

  Further, since the xenon discharge tube 40 is a quartz tube, the heat resistance is better than that of a glass tube. Thereby, even if continuous light emission is performed, a crack does not arise. Further, the conductive connection between the discharge electrode of the xenon discharge tube 40 and the discharge lead wire 46 is performed by caulking of the copper sleeve 48, and the conductive connection between the trigger electrode connection terminal 50 and the trigger lead wire 52 is also caulked. As a result, the heat resistance of these connection parts is improved as compared with the case of soldering. These also increase the number of times (time) at which continuous light emission is possible.

  Although the present invention has been described above with reference to preferred embodiments, the present invention is not limited to such embodiments so that those skilled in the art can easily understand, and departs from the spirit of the present invention. It is possible to change appropriately within the range not to be. For example, the guide bar 26 does not necessarily need to be made of ceramics, and may be made of a nonconductive material for the purpose of avoiding a short circuit discharge with the concave mirror 42. Depending on the specifications, the guide bar 26 may be made of a synthetic resin excellent in heat resistance such as a high heat resistant polyamide resin, a high heat resistant epoxy resin, or a high heat resistant polyamide imide resin. The zoom movement of the lamp holder 30 may be manual instead of electric. The strobe device according to the present invention is not limited to a strobe device having a light emitting portion (front shield plate 16) having a square shape, and can be similarly applied to a strobe device having a circular light emitting portion.

  In addition, all the components shown in the above embodiment are not necessarily essential, and can be appropriately selected without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 Electrical part outer case 12 Light emission part outer case 16 Front shield plate 18 Housing 20 Lens support member 24 Fresnel lens 26 Guide bar 30 Lamp holder 32 Electric motor 34 Screw rod 36 Wire member 40 Xenon discharge tube 42 Concave mirror 44 Discharge tube fixture 44A Waveform part 44B Ring part 50 Trigger electrode connection terminal 54 Auxiliary trigger electrode

Claims (7)

A box-shaped housing with a front opening;
A Fresnel lens attached to the front of the housing;
A guide bar attached to the housing and extending in the front-rear direction in the housing;
A lamp holder with a front opening that engages with the guide bar and is guided by the guide bar and movable in the front-rear direction in the housing;
Light emitting means provided in the lamp holder;
A concave mirror that is attached to the lamp holder and reflects light emitted from the light emitting means to the front opening side of the housing and emits light forward from the front opening;
A strobe device in which the lamp holder is a ceramic product.   2. The strobe device according to claim 1, wherein the light emitting unit is configured by a xenon discharge tube, the concave mirror is configured by a conductive material, and serves as a trigger electrode of the xenon discharge tube.   The strobe device according to claim 2, wherein the guide bar is made of a non-conductive material.   The strobe device according to claim 2, wherein the guide bar is formed of a ceramic molded product. A discharge tube mounting made of a metal wire having a corrugated portion extending in the left-right direction along the back surface of the lamp holder, and ring portions fitted to the outer periphery of the end portion of the xenon discharge tube at both ends of the corrugated portion Have tools,
The said xenon discharge tube is being fixed to the said lamp holder in the state pressed against the said concave mirror of the site | part located in the back side of the said xenon discharge tube by the said discharge tube fixture. The strobe device described.   The strobe device according to claim 5, wherein the ring portion of the fixture forms another trigger electrode of the xenon discharge tube.   The strobe device according to any one of claims 1 to 6, wherein the Fresnel lens is made of glass.

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