JPH0435867Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial field of application The present invention relates to an electronic flash device that can vary the angle of light emission by moving a small flash discharge tube, which can be regarded as a point light source, in the direction of the light emission axis using a motor. be.

Conventional technology In recent years, the use of zoom lenses has become common in photographic cameras, and it is important for the effective use of energy that the emission angle of the electronic flash device used in conjunction with the camera also matches the set shooting angle of view. Various such means for varying the light emitting irradiation angle have been proposed, which are desirable from this point of view.

For example, in Japanese Patent Application Laid-open No. 55-129326, as shown in FIG. A device is disclosed in which the light emission angle is varied by moving the light emission light in the direction of the light emission optical axis L.

Furthermore, as shown in the cross-sectional view of FIG. 6, Japanese Patent Application Laid-Open No. 60-83921 discloses a lens barrel case forming an outer frame for a light emitting unit 4 comprising a rod-shaped flash discharge tube 2 and a reflector 1. A condensing lens 6 disposed on the front side of the section 5
A device is disclosed in which the light emitting unit 4 is provided movably in the optical axis direction L, and is moved by supplying driving force from a motor 7 to the light emitting unit 4 through a gear train 8, thereby varying the light emission angle.

Furthermore, the device disclosed in JP-A-60-83921 differs in that the main body that moves is different, that is, although not shown, the reflector and flash discharge tube are fixed, and the light condensing device is arranged in front of them. This is a device that changes the angle of light emission by moving the lens along the light emission axis manually or automatically using a motor.

Problems to be Solved by the Invention However, all of the above-mentioned devices have the following problems.

First, since the device shown in Fig. 5 moves a rod-shaped flash discharge tube in the direction of the light emitting optical axis, great care must be taken to prevent the flash discharge tube from wobbling. Care must also be taken against light leakage from the long holes on the sides.

In other words, if the flash discharge tube moves diagonally, its light distribution characteristics will be such that the peak direction deviates from the facing position, and light leakage may occur, for example, if a camera has an electronic flash device built-in. Considering this, it is clear that consideration must be taken to prevent the film from reaching the film surface, which cannot be said to be preferable.

Next, since the device shown in Fig. 6 controls the luminescence irradiation angle by the distance between the flash discharge tube as the light source and the condensing lens, in order to obtain the necessary variable state of the irradiation angle, However, there is a problem in that the amount of movement of the light source, that is, the light emitting unit is quite large, which inevitably increases the size of the device.

Furthermore, since the drive method using a gear train is disclosed, the number of parts increases, resulting in a complicated structure, which also has the problem of increasing costs.

Finally, there is a means for moving a condensing lens (not shown), and although the moving body is different, the principle of changing the light emission angle is the same as the fifth one.
This is similar to the means shown in the figure, and therefore has problems such as the amount of movement of the condensing lens becoming large and the device becoming larger.

An object of the present invention is to provide an electronic flash device that can solve the above-mentioned problems.

Means for Solving the Problems The electronic flash device according to the present invention includes a transparent cylindrical envelope having an open end at one end, a pair of main electrodes, and a plurality of spaces connected in series inside the envelope. The dividing means for dividing into two, a rotation preventing member and a driving force transmitting member, which are protrusions or protrusions, for example, are integrally formed, and the pair of main electrodes are airtightly positioned on the open end side of the plurality of spaces. a small flash discharge tube that can be regarded as a substantially point light source, and includes a ceramic base sealed at the open end so as to hold a predetermined gas in the envelope; and the rotation prevention member and the drive. a reflecting umbrella provided with a sliding part on which the force transmitting member can slide and a holding part for holding the small flash discharge tube so as to be able to slide in the optical axis direction; and a driving source that is, for example, a stepping motor. a cam member that is fixed to the rotation shaft of the motor and has a drive output member at a position different from the rotation shaft, one end of which is connected to the drive force transmission member, and the other end of which is connected to the drive force output member. It is configured to include a transmission plate that is connected to transmit the driving force of the motor to the small flash discharge tube, and a drive control means that controls the amount of drive of the motor by a signal that is manually or automatically supplied.

Function Since the electronic flash device according to the present invention has the above-mentioned configuration, the driving force of the drive source is transmitted to the small flash discharge tube via the cam member and the transmission plate, so that the small flash discharge tube rotates. Due to the relationship between the blocking member and the sliding portion of the reflector, it slides in the optical axis direction at the holding portion.

That is, the small flash discharge tube that is the light source moves relative to the reflector, and the amount of movement required is extremely small.

In addition, the movement itself is limited because the light source is a compact flash discharge tube sealed on one side with a dividing means inside the envelope, and the direction of movement is along the discharge path of the discharge tube. By appropriately designing the holding portion of the reflective umbrella so that only the portion that does not emit light can almost eliminate the risk of light leakage.

Embodiment FIG. 1 is an exploded perspective view of the main parts of an embodiment of the electronic flash device according to the present invention, that is, the part that controls the light emission angle.

In the figure, reference numeral 9 denotes a small flash discharge tube that can be regarded as a point light source, which will be described later. Reference numeral 10 denotes a protrusion that is a rotation prevention member that is integrally provided on a ceramic base, which will be described later, and which constitutes a part of the small flash discharge tube 9. 1 shows a first protruding pin which is a driving force transmitting member that is integrally provided on a ceramic base body, which will be described later, like the protruding portion 10 described above.

12 indicates a reflective umbrella, the above-mentioned protrusion 10, the first
The groove 14 is a sliding part on which the protruding pin 11 slides.
It has a holding part 13 into which the small flash discharge tube 9 is slidably inserted. It goes without saying that the holding portion 13 is sized in consideration of the shape and amount of movement of the small flash discharge tube 9, that is, the holder 13 is sized to prevent light leakage.

15 is a driving source such as a stepping motor, and 16 is fixed to and rotates the rotating shaft 15a of the motor 15, and the rotating axis thereof.
The second drive force output member is located at a different position than _L1 .
A cam member having a protruding pin 17 is shown.

18 has a hole 18a into which the above-mentioned first protruding pin 11 is fitted at one end, and a hole 18b into which the above-mentioned second projecting pin 17 is fitted into the other end, and moves with the small flash discharge tube 9 and the cam plate 16. Fig. 3 shows transfer plates that can be connected.

19 is fixed to, for example, a device substrate (not shown), and has a plurality of conductive patterns 20 on the surface 19a.
21 is a brush which is fixed to the cam plate 16 rotated by the drive source 15 and which generates various electrical signals by coming into contact with the conductive pattern 20 described above.

Reference numeral 22 indicates a drive control means for controlling the drive operation of the motor 15, that is, the amount of rotation, manually or by a signal automatically supplied from the camera.

Next, we will describe the operation of an embodiment of the electronic flash device according to the present invention having the above-mentioned configuration.Before that, we will first explain an example of a small flash discharge tube indicated by reference numeral 9 in FIG. A brief explanation will be given with reference to the cross-sectional view shown in FIG.

As is clear from FIG. 2, the small flash discharge tube 9 used in the present invention has an anode 24 and a cathode 25 at one end of an envelope 23 made of glass, for example, and the electrodes 24 and 25 are kept airtight. The interior of the envelope 23 is connected in series by a dividing means 26a that is positioned through a ceramic base 26 that is sealed to the envelope 23, and is integrally formed on the ceramic base 26. It is divided into spaces 23a and 23b.

Therefore, the discharge path has a U-shape as shown by the broken line in FIG. 2, and as a result, an efficient discharge length can be realized in a compact shape, that is, it can be regarded as a substantially point light source.

In addition to the above-mentioned dividing means 26a, the ceramic base 26 also includes the first protruding pin 11, which is the driving force transmitting member, and the protruding portion 10, which is a rotation preventing member, although not shown in the drawings. By controlling the shape of the dividing means 26a, it is possible to form various discharge paths, such as dividing the space into four and forming two U-shaped discharge paths. Needless to say.

As mentioned above, the flash discharge tube used in the present invention is a small flash discharge tube that can be regarded as a point light source with the envelope divided into multiple spaces forming discharge paths and a main electrode sealed on one side. 3 and 4 a and b for the operation of an embodiment of the electronic flash device according to the present invention, which employs such a small flash discharge tube and has the main parts shown in FIG. 1. and explain.

FIG. 3 is a schematic vertical sectional view including a partial side view of the assembled components shown in FIG. As is clear from FIG. 3, the small flash discharge tube 9 is located within the holding part 13 of the reflector 12, and
The transmission plate 18 is connected to the small flash discharge tube 9 and the cam plate 16 via holes 18a, 18b, a first protruding pin 11, and a second protruding pin 17.

Further, FIGS. 4a and 4b are plan views including partial cross sections of the assembled components shown in FIG. 1, each showing one state based on the rotational operation of the motor 15.

The fact that the state shown in FIG. 4a corresponds to the state shown in FIGS. 1 and 3 means that the second protruding pin 17
This is also clear from the fact that the position is located closest to the reflector 12.

Now, when the motor 15 starts rotating from the state shown in FIGS. 1 and 3, that is, the state shown in FIG. The second protruding pin 17 provided on the cam plate 16 changes its position relative to the small flash discharge tube 9 in the direction away from it.

In other words, when the cam plate 16 rotates in the state shown in FIGS. 1, 3, etc., the second protruding pin 17 is moved to the right in FIG. This means that they will have to move.

By the way, as described above, the second protruding pin 17 is connected to the transmission plate 18 through the hole 18b, and therefore, the transmission plate 18 does not tilt as the second protruding pin 17 moves as described above. The third of what arises
Referring to the figure, this means that it is moved to the right.

On the other hand, the transmission plate 18 is connected to a first protrusion pin 11 provided on the small flash discharge tube 9 through a hole 18a at the other end, and the moving force of the transmission plate 18 is applied to the first protrusion pin 11. The light is transmitted to the small flash discharge tube 9 via the light beam, and acts to move the discharge tube 9.

At this time, the force supplied to the small flash discharge tube by the transmission plate 18 is in the right direction as shown in FIG. 3, but as shown in FIG. Needless to say. However, the small flash discharge tube 9
Since the protruding portion 10 and the first protruding pin 11 are attached to slide in the groove 14, the small flash discharge tube 9 itself moves linearly, that is, the light emitting optical axis L ₂
It can only move along the direction, and as a result of the movement of the transmission plate 18 described above, it will move linearly to the right in FIG. 3 or 4a.

As a result, the position of the small flash discharge tube 9 with respect to the reflector 12 is changed, and the light emission angle of the device is changed.

Furthermore, the motor 15 rotates, and the above-mentioned transmission plate 1
When the cam plate 16 is rotated 180 degrees while the small flash discharge tube 9 is moving to the right in FIG. 3, the position of the second protruding pin 17 is as shown in FIG. It reaches the position rotated 180 degrees from the position shown, that is, the position shown in FIG. 4b, and is farthest from the reflector 12.

Therefore, the transmission plate 18 and the small flash discharge tube 9, which had been moved by the rotational movement of the second projecting pin 17, are also moved to the position shown in FIG. 4b, that is, the rearmost position with respect to the reflector. It will be located in

When the motor 15 continues to rotate further, the cam plate 16
Due to the rotation of the second protruding pin 17, the position shown in FIG.
Contrary to the case described above, the transmission plate 18 and the small flash discharge tube 9 are rotated toward the position shown in FIG. Needless to say, it will continue to move.

As described above, in one embodiment of the electronic flash device according to the present invention, the rotational force of the motor 15 is applied to the second projecting pin 17 of the cam plate 16, the transmission plate 18, and the first
The light is transmitted to the small flash discharge tube 9 through the protruding pin 11, and the small flash discharge tube 9 moves in the optical axis direction between FIG. This makes it possible to control the light emission angle.

Therefore, the driving operation of the motor 15 is appropriately controlled,
By controlling the position of the second protruding pin 17 of the cam plate 16 and appropriately setting the position of the reflector 12 of the small flash discharge tube 9 within the holding part 13, the light emission angle corresponding to the set position is set. It will be possible. In order to control the position of the second protruding pin 17, the rotation state of the cam plate 16 is extracted as an electric signal by the base plate 19 and the brush 21 shown in FIG. This can be easily realized by applying a motor control technique, which is a well-known drive source, to appropriately control the amount of rotation of the motor 15. In addition, when a stepping motor is used as the motor 15, as it is well known that the amount of rotation of a stepping motor can be controlled by the number of supplied pulses, it is possible to control the rotation amount by appropriately weighting the number of supplied pulses. It goes without saying that the position of the second projecting pin 17 can be controlled by rotating the cam plate 16 without using the substrate 19 and brush 21 described above.

Furthermore, a second protruding pin 17 on the cam plate 16
It goes without saying that the overall movement amount of the small flash discharge tube 9 can be controlled by changing the formation position of the small flash discharge tube 9. That is, if the second protruding pin 17 is provided near the rotation center of the cam plate 16, the maximum movement width of the small flash discharge tube 9 shown in FIGS. 4a and 4b becomes smaller, and conversely, the rotation When provided at a location far from the center, the maximum movement width can be increased.

Effect of the invention In the electronic flash device according to the invention, the dividing means, the rotation preventing member, and the driving force transmitting member are integrally formed, and the pair of main electrodes are kept airtight and sealed at the open end of the envelope. A small flash discharge tube that is substantially a point light source by using a ceramic base made of ceramic, and a reflective umbrella that includes a sliding part of the rotation prevention member and a driving force transmission member, and a holding part for the small flash discharge tube are assembled. In addition, the driving force of the motor is transmitted to the small flash discharge tube through a cam member and a transmission plate without using a gear system, and the small flash discharge tube is held within the holding part of the reflector. By moving the light emitting light in the direction of the optical axis,
The number of parts can be reduced, so the overall shape of the electronic flash device can be made smaller and its configuration can be simplified, and the light emission angle can be controlled at low cost without fear of light leakage.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of the main parts of an embodiment of the electronic flash device according to the present invention, FIG. 2 is a sectional view showing an example of a small flash discharge tube used in the electronic flash device according to the present invention, and FIG. 1 is a vertical sectional view including a partial side view of an embodiment of the electronic flash device according to the present invention in a state where the main parts shown in FIG. 1 are combined, and FIGS. A partially sectional plan view, FIG. 5, and FIG. 6 are a perspective view and a schematic cross-sectional view, respectively, for explaining conventional means for controlling the light emission angle. 9...Small flash discharge tube, 10...Protrusion part (rotation blocking member), 11...First protrusion pin (driving force transmission member), 12...Reflector, 13...Holding part, 1
4... Cut groove (sliding part), 15... Motor, 16...
...Cam member, 17...Second protruding pin (driving force output member), 18...Transmission plate, 19...Substrate, 20
. . . conductive pattern, 21 . . . brush, 22 . . . drive control means.

Claims (1)

[Scope of utility model registration request] A translucent cylindrical envelope having an open end at one end, a pair of main electrodes, a dividing means for dividing the inside of the envelope into a plurality of serially connected spaces, a rotation preventing member, and a driving force transmitting member are integrated. the pair of main electrodes are held airtight so as to be positioned on the open end side of the plurality of spaces, and the open end is sealed so as to seal a predetermined gas in the envelope. A small flash discharge tube is provided with a ceramic base to which it is mounted, and a sliding portion on which the rotation prevention member and the driving force transmission member can slide, and the small flash discharge tube can be slid in the optical axis direction. a motor serving as a drive source; a cam member fixed to a rotation shaft of the motor and having a drive output member at a position different from the rotation shaft; a driving force transmitting member, a transmission plate whose other end is connected to the driving force output member and transmits the driving force of the motor to the small flash discharge tube, and a signal manually or automatically supplied to indicate the driving amount of the motor. An electronic flash device having a drive control means for controlling the electronic flash device.