JPH02160226A - Eyepiece shutter driving device - Google Patents

Abstract

PURPOSE:To obtain the driving device of an eyepiece shutter which opens and closes with power and to reduce the cost by utilizing a motor which is used for bringing up and down a stroboscopic device as the driving source for the opening and closing of the eyepiece shutter. CONSTITUTION:The driving device is provided with the eyepiece shutter opening and closing mechanism which opens and closes the eyepiece shutter 42 by the revolution of a revolving member 48, and a change-over driving mechanism 35 which selects the driving power of the motor 31 of the stroboscopic driving device and transmits it to the revolving member 48 of the eyepiece shutter opening and closing mechanism. Thus, the opening and closing of the eyepiece shutter 42 is powered, and since a motor 31 which performs bringing up and down the stroboscopic devices as the driving source is utilized, the cost is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to an eyepiece shirt for an eye reflex camera.

[Prior art and its problems] - In an eye reflex camera, when taking close-up shots, copying, or long exposures in which the eye is removed from the viewfinder eyepiece, there is a risk that the exposure will be distorted if reverse light enters from the eyepiece. be. The eyepiece shutter is used to prevent light from traveling backwards from the finder eyepiece window in such cases. However, all conventional eyepiece shutters have to be opened and closed manually and are complicated to operate.

``Object of the Invention'' The present invention has an object to obtain an eyepiece shutter driving device that uses power for opening and closing, and further aims to obtain an eyepiece shutter driving device that does not require an independent drive source for powering. do.

"Summary of the Invention" The present invention was completed based on the idea that if the up-down motor of a strobe device is used as the drive source for opening and closing the eyepiece shutter, a drive device that does not have a complicated device configuration and is inexpensive can be obtained. It is what was done.

That is, the present invention provides a single-lens reflex camera that has a motor-driven strobe drive device that raises and lowers the light emitting part of the strobe device, and an eyepiece shutter that opens and closes the eyepiece window of a finder device, in which the eyepiece shutter is opened and closed by rotation of a rotating member. The eyepiece shutter opening/closing mechanism is characterized by comprising an eyepiece shutter opening/closing mechanism, and a switching drive mechanism selectively transmitting the driving force of the motor of the strobe drive device to the rotating member of the eyepiece shutter opening/closing mechanism.

This switching drive mechanism has, for example, a switching lever that rotatably supports a planetary gear that meshes with the main gear coaxially with a main gear rotationally driven by a motor, so that the switching lever can be rotated according to the forward or reverse rotational direction of the motor. The switching lever is configured to swing, and the swinging of the switching lever converts the planetary gear into a rotating gear member that opens and closes the eyepiece shutter opening/closing mechanism and a rotating gear member that raises and lowers the light emitting part of the strobe device. , can be configured by selectively engaging them.

“Embodiments of the invention” The invention will now be described with reference to the illustrated embodiments.

A strobe device (light emitting section) 12 is located in front of the pentaprism P of the eye reflex camera 11 (FIG. 5).

This strobe device 12 has a xenon tube 15 and a reflector 16 mounted on an up-down frame 14 that is rotatable around a shaft 13.
By rotating the up-down frame 14, the xenon tube 15 and the reflector 16 move between the storage position and the protruding position (use position). This up-down frame 14 is biased upward to the protruding position by a spring means (not shown).

To explain the drive mechanism of this strobe device 12, the up-down frame 14 is provided with a position regulating bin 17 on its side, and this position regulating bin 17 is engaged with the operating arm 18a of the up-down control lever 18. There is. The up-down control lever 18 is pivotally connected to the camera body by a shaft 19, and depending on the rotational position of the up-down control lever 18,
The up-down position of the up-down frame 14 is regulated.

The control arm 18b at the other end of the up/down control lever 18 is
It engages with a cam member 21 provided on the rotating gear member 20. The cam member 21 is provided at an eccentric position with respect to the rotation center of the rotary gear member 20, and the cam member 21 is provided at an eccentric position with respect to the rotation center of the rotating gear member 20.
Rotating gear member 20 is positioned upward as shown in FIG.
When the control arm 18b is rotated, the control arm 18b is pushed up and the operating arm 18a is lowered, and the up-down frame 14 is held at the storage position via the position regulating bin 17. On the other hand, when the rotary gear member 20 rotates so that the cam member 21 is positioned downward as shown in FIG. 21
Its protruding position (usage position) is regulated at the position where it abuts.

Therefore, in the illustrated example, the strobe device 12 moves between the protruding position and the retracted position by the intermittent rotation of the rotating gear member 20 by 180@.

The rotating gear member 20 is rotationally driven via a motor 31, a pinion 32 fixed to the output shaft of the motor 31, a parent gear 33 that meshes with the pinion 32, and a planetary gear 34 that meshes with the parent gear 33. The planetary gear 34 is supported by a switching lever 35 that is coaxial with the parent gear 33 and is rotatable relative to it. When the parent gear 33 rotates in the direction of the solid line arrow in FIG. 1, the switching lever 35 rotates in the same direction. and planetary gear 3
4 and the rotating gear member 20 mesh with each other.

On the other hand, a finder device 40 of the eye reflex camera 11 is provided with a pair of eyepiece shutters 42 in an eyepiece window 41 so as to be openable and closable. This eyepiece shutter 42 consists of a pair of X-shaped arms 4 that are pivotally connected to the camera body via a shaft 43.
The eyepiece shutter 42 is pivotally connected to one end of the
opens and closes the eyepiece window 41.

At the ends of the pair of X-shaped arms 44 opposite to the eyepiece shutter 42, parallel cam interlocking arms 46 are bent, and a tension spring 47 is stretched.
The pair of cam interlocking arms 46 are urged in a direction toward each other, that is, in a direction in which the eyepiece shutter 42 is always closed. A rotating gear member 4 is provided between the pair of cam interlocking arms 46.
A cam member 49 fixed to 8 is located. This cam member 49 has an elliptical shape, and when its long axis is positioned between the pair of cam interlocking arms 46, the eyepiece shutter 42 opens, and when its short axis is positioned, the eyepiece shutter 42 closes. Therefore, in this example, the eyepiece shutter 42 is opened and closed by the intermittent rotation of the rotating gear member 48 by 90 degrees. When the main gear 33 rotates in the direction of the broken line in FIG. 1 and the switching lever 35 swings in the same direction, this rotating gear member 48
It meshes with the planetary gear 34.

The rotating gear member 20 and the rotating gear member 48 are provided with rotation angle detection means 50 and 51, respectively. The rotation angle detection means 50 detects the protruding position and the retracted position of the strobe device 12 from the rotation angle of the rotating gear member 20, and provides a stop signal to the motor 31 via the motor control circuit 52. Further, the rotation angle detection means 51 similarly detects the rotating gear member 4.
The open position and closed position of the eyepiece shutter 42 are detected from the rotation angle of 8, and the motor 31 is controlled via the motor control circuit 52.
give a stop signal.

Signals from a strobe up/down switch 53 and an eyepiece shutter open/close switch 54 are input to the motor control circuit 52 . The motor control circuit 52 rotates the binion 32 in the direction of the solid arrow when a signal is input from the strobe up/down switch 53, and rotates the binion 32 in the direction of the dashed arrow when a signal is input from the eyepiece shutter open/close switch 54. Rotate. The strobe up/down switch 53 may be configured as a manual switch, or may be turned on in conjunction with a photometry circuit when the brightness of the subject is below a certain value. The eyepiece shutter open/close switch 54 may be configured as a manual switch, or may be turned on during self-timer photography or remote photography by being linked to a self-timer photography control circuit or the like.

In this apparatus having the above configuration, it is assumed that the strobe device 12 is now in the storage position and the eyepiece shutter 42 is in the open position (FIG. 1). When the strobe up/down switch 53 is turned on in this state, the binion 32, the parent gear 33, and the switching lever 35 are rotated in the direction of the solid arrow via the motor control circuit 52, and the planetary gear 34 and the rotating gear member 20 are engaged.

Therefore, the rotating gear member 20 rotates in the direction of the solid line, and the strobe device 12 (up-down frame 14
) moves from the retracted position to the extended position. When the rotation angle of the rotating gear member 20 reaches 180' (that is, when the strobe device 12 moves to the protruding position), the rotation angle detection means 50 detects this and sends a stop signal to the motor 31 via the motor control circuit 52. (Figure 3). When the strobe up/down switch 53 is turned on again, the rotating gear member 20 rotates 1801 times through the same rotational drive path again, and the strobe device 12 moves from the protruding position to the retracted position. When the strobe device 12 moves up and down, no rotation is applied to the rotating gear member 48, so the ibis shutter 42 does not close.

On the other hand, when the eyepiece shutter open/close switch 54 is turned on, the pinion 32
rotates in the direction of the dashed arrow. Then, the main gear 33 and the switching lever 35 rotate in the direction of the broken line arrow, and the planetary gear 3
4 disengages from the rotating gear member 20 and meshes with the rotating gear member 48. Therefore, the rotating gear member 48 rotates in the direction of the dashed arrow, and the eyepiece shutter 42 closes via the cam member 49, the cam interlocking arm 46, and the X-shaped arm 44.

Then, when the rotation angle of the rotating gear member 48 reaches 90'' (
That is, when the eyepiece shutter 42 is closed, the one rotation angle detection means 51 detects this and issues a stop signal to the motor 31 via the motor control circuit 52 (FIG. 2). When the eyepiece shutter open/close switch 54 is turned on again, the rotary gear member 48 is rotated 90'' by the same rotational drive path again.
The eyepiece shutter 42 now moves from the closed position to the open position. During the opening/closing operation of the eyepiece shutter 42, no rotation is applied to the one-rotation gear member 20, so the strobe device 12 does not move up or down.

The up-down mechanism of the strobe device 12 and the opening/closing mechanism of the eyepiece shutter 42 shown in the above embodiments are simple examples, and the present invention is not limited thereto.

"Effects of the Invention" As described above, the eyepiece shutter drive device of the present invention has the following features:
Since the opening and closing of the eyepiece shutter is powered, it provides a smoother and more sophisticated operating feel compared to manual opening and closing.Also, since the motor used to raise and lower the strobe device is used as the drive source, it can be driven independently. Compared to the case where a source is provided, cost can be reduced.

[Brief explanation of the drawing]

1 and 2 are perspective views of the main parts of the eyepiece shutter in the open and closed states, showing an embodiment of the eyepiece shutter driving device of the present invention, and FIGS. 3 and 4 are similar to the strobe up position. FIG. 5 is a side view showing the (protruding position) and down position (storage position), and FIG. 5 is a perspective view showing the relationship with the entire single-lens reflex camera. 11... - eye reflex camera, 12... strobe device (
light emitting part), 14...up-down frame, 15...xenon tube, 16...reflector, 17...position regulation bin,
18... Up/down control lever, 20... Rotating gear member, 21... Cam member, 31... Motor, 32
... Binion, 33 ... Main gear, 34 ... Planetary gear, 35 ... Switching bar, 40 ... Finder device, 41 ... Eyepiece window, 42 ... Eyepiece shutter, 44 ...X-shaped arm, 46...Cam interlocking arm, 47
...Tension spring, 48... Rotating gear member, 49...
Cam member, 5o, 51... Rotation angle detection means, 52...
- Motor control circuit, 53... Strobe up/down switch, 54... Eyepiece shutter open/close switch. Figure 2 Patent applicant: Asahi Optical Industry Co., Ltd. Agent: Kunio Miura

Claims (4)

[Claims] (1) A motor-driven strobe drive device that raises and lowers the light emitting part of the strobe device between a used state and a stored state;
In a single-lens reflex camera having an eyepiece shutter that opens and closes an eyepiece window of a finder device, an eyepiece shutter opening/closing mechanism opens and closes the eyepiece shutter by rotation of a rotating member, and the eyepiece shutter opening/closing mechanism uses the driving force of the motor of the strobe drive device. An eyepiece shutter drive device comprising: a switching drive mechanism that selectively transmits transmission to a rotating member of the eyepiece shutter drive mechanism. (2) In claim 1, the switching drive mechanism includes a parent gear rotationally driven by a motor, a switching lever that rotatably supports a planetary gear that meshes with the parent gear and is coaxially supported with the parent gear, and an eyepiece. The pair of rotating gear members includes a rotating gear member that opens and closes the shutter opening/closing mechanism and a rotating gear member that raises and lowers the light emitting part of the strobe device, and the pair of rotating gear members swing according to the forward and reverse rotational directions of the motor. An eyepiece shutter drive device characterized by selectively engaging a planetary gear of a switching lever. (3) The eyepiece shutter drive device according to claim 2, wherein the rotating gear member of the eyepiece shutter opening/closing mechanism includes a cam member, and the cam member opens and closes the eyepiece shutter in accordance with rotation of the rotating gear member. (4) The eyepiece shutter drive device according to claim 2, wherein the rotating gear member of the strobe drive device includes a cam member, and the cam member moves the light emitting section up and down in accordance with the rotation of the rotating gear member.