JPS6151785B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a drive device for a motor drive camera;
More specifically, the present invention relates to a drive device for a motor drive camera that drives a mirror or apertures using a simple mechanism.

The inventors of the present invention focused on eliminating the large energy required for charging of the conventional quick release mechanism by giving the mirror mechanism a direction in which it always maintains an observation state, that is, giving the mirror mechanism a mirror downward behavior, and developed such a mirror. Drive mechanism (1977-)
37895 (Utility Model Application Publication No. 54-541938)) has already been proposed.

An object of the present invention is to improve the drive mechanism of a motor drive camera as described above, and to provide a drive mechanism of a motor drive camera that can perform mirror drive or aperture drive using a simpler mechanism.

To achieve the above object, a first configuration of a drive mechanism for a motor drive camera according to the present invention includes: a motor that rotates in forward and reverse directions; a ratchet gear to which rotation of the motor is transmitted via a reduction gear train;
A link arm whose one end is biased to engage with the ratchet gear and receives driving force from the ratchet gear, and the other end of the link arm is pivotally supported and receives driving force from the ratchet gear via the link arm. The mirror mechanism is provided with the habit of returning to the observed state, and a driving force is applied from the lever against this habit of returning to the observed state, and the motor moves the ratchet gear to the first position. By rotating in the direction, the lever is pushed around via the link arm, and the three points of the center of the ratchet gear, the engagement position of the ratchet gear and the link arm, and the pivot point of the link arm are aligned. When the mirror is on the line, the raising of the mirror is terminated, and after the shutter is closed, the ratchet gear is rotated in the second direction to return the mirror.

Furthermore, a second configuration of the drive mechanism of a motor drive camera according to the present invention includes a motor that rotates in forward and reverse directions, a ratchet gear to which the rotation of the motor is transmitted via a reduction gear train, and one end of which is connected to the ratchet gear. a link arm that is biased to engage with the lever and receives a driving force from the ratchet gear, and a lever whose other end is pivotally supported and rotates by receiving the driving force from the ratchet gear via the link arm. and a narrowing lever which is given a return habit to the open state and to which a driving force is applied from the lever against this return habit, and the ratchet gear is rotated in a first direction by the motor. , when the narrowing lever is driven via the link arm, and the center of the ratchet gear, the engagement position of the ratchet gear and the link arm, and the pivot point of the link arm are aligned in a straight line. After the drive of the aperture lever is finished and the shutter is closed, the ratchet gear is rotated in a second direction to return the aperture lever.

According to the above configuration, the object of the present invention can be completely achieved.

The drive mechanism of the motor drive camera according to the present invention will be described in more detail below with reference to the drawings and the like.

FIGS. 1A and 1B are explanatory diagrams for explaining the arrangement of the internal structure of a single-lens reflex camera to which the mirror drive mechanism is applied.

A motor 1 placed inside the camera has output shafts at the top and bottom. A battery that supplies current to this motor 1 is housed at the bottom of the camera. In FIG. 1B, 28 is a mirror driven and controlled by a mechanism according to the invention.

This motor 1 is rotated in forward and reverse directions by a circuit (not shown), and the film is wound and shuttered by rotation in one direction.

This rotation in the first direction is transmitted from the upper shaft of the motor 1 shown in FIG. 1B through the gear 2.
Rotation in the other direction is from the lower shaft of motor 1 to gear 3.
is configured to drive the mirror and perform the aperture operation.

FIG. 2 is a perspective view showing the transmission mechanism and control mechanism in the second direction.

The rotation of the motor 1 in the direction indicated by the arrow a shown in FIG. 2 corresponds to the rotation in the other direction, and the rotation in the direction of the arrow b corresponds to the rotation in the one direction. A one-way clutch is provided in the transmission system so that mirror drive in the direction of arrow a and rotation in the direction for narrowing down do not affect winding or the like.

This camera is constructed so that, immediately after the shutter is released, the shutter is charged and the film is wound in preparation for the next shutter release.

Then, the motor 1 is driven in the direction a by the release signal to perform a series of operations such as raising the mirror, setting the aperture, and releasing the shutter.Then, the motor 1 is rotated in the direction b to lower the mirror and wind the film. Above, it is used to charge the shutter.

When a release signal is applied to the camera, the motor 1 is rotated in the direction a by a motor control circuit (not shown). This rotation is transmitted to the trigger charge gear 5 via a reduction gear train 4 connected to the lower pinion 3. The trigger charge gear 5 is
It is rotated in the clockwise direction indicated by the arrow a shown at the gear.

A pin 6 is implanted in the trigger charge gear 5, and the pin 6 is removed by pushing the pawl 7 counterclockwise. This merely causes the pawl 7 to swing back against the spring 17, causing the pawl 7 to swing back in vain, and does not affect the pawl 8 connected to the pawl 7. This rotation of gear 5 is transmitted to gear 9, and gear 9 is rotated counterclockwise.

A ratchet gear 10 is provided on the gear 9 so as to be rotatable coaxially therewith.

Figures 3 and 4 are explanatory diagrams for explaining the relationship between the ratchet gear and the mirror lever narrowing lever. Figure 3 shows the mirror in the lowered position, and Figure 4 shows the mirror in the raised position. It is shown in the state shown in .

The gear 9 and the ratchet 10 are provided so as to be rotatable together around a shaft 40. mirror lever 15
and the narrowing lever 21 are each provided rotatably about the shaft 16.

The tip of the mirror lever 15 can be engaged with the lower end of a mirror up lever 25 of the mirror mechanism.

As shown in FIG. 2, the mirror up lever 25 is rotatably provided on the wall surface, and the other end is
It is a forked part of a and 25b. This portion 25a is engaged with a mirror pin 27 that is rotatable together with the mirror 28. The mirror up lever is given a clockwise rotational force by a spring 26. This spring 26 and a spring (not shown) cause the mirror mechanism as a whole to rotate the mirror with respect to the optical axis.
The mirror up lever 25 is biased in the direction of maintaining the angle at 45 degrees, that is, in the direction of rotating the mirror up lever 25 clockwise in FIG. Therefore, the mirror mechanism lever 15
is being pushed counterclockwise by the mirror up lever 25 in FIG.

A link arm 11 is rotatably provided on the mirror drive lever 15, and a pin 13 is implanted at the tip of the link arm 11 so as to engage with the ratchet gear 10 described above.

The link arm 11 is urged counterclockwise around the shaft 14 by a spring 12 so that the pin 13 contacts the ratchet gear 10. Aperture lever 21 that is rotatable coaxially with the mirror drive lever
A counterclockwise rotational force is applied by a spring 22, and the mirror drive lever 15 can be driven by a pin 20 provided at one end.

The aperture lever 23 on the lens side shown in FIGS. 3 and 4 is biased toward the left in each figure, but the biasing force is the same as that of the aperture lever 23 on the camera side.
1 is smaller than the counterclockwise rotational force at the engagement point provided by the spring 22.

Now, as mentioned above, when the motor 1 is rotated in the direction of the arrow a in FIG. 2 by application of the release signal, the trigger charge gear 5 is shown in FIG.
is rotated clockwise, causing gear 9 to rotate counterclockwise and the ratchet gear to rotate in the first direction indicated by arrow a.

The spring 12 pushes the pin 13 of the link arm 11, which is connected to the valley of the ratchet gear, pushing the mirror drive lever 15 clockwise.

Therefore, the mirror drive lever 15 pushes the mirror up lever 25 upward in FIG. 3 and counterclockwise in FIG. 2, and similarly pushes the aperture lever 21 clockwise by pushing the pin 20. One end 25a of the mirror up lever hits a pin 27 that is provided integrally with the mirror 28, and pushes the mirror 28 up toward the center of a hinge (not shown). The aperture lever 21 allows the lens-side aperture lever 23 to move leftward (restriction) in FIG. 3.

By rotating the mirror up lever 25, the mirror 2
8, when the ascent is almost completed, 2 of the lever 25 is pressed.
5b pushes the 29a part of the hook 29 shown in FIG. 2 and moves against the spring 30 around the hook shaft 31,
Rotate the hook 29 clockwise.

The hook 29 prevented clockwise rotation of the trigger lever 32, but 32a of the trigger lever 32
is removed from the hook 29, and the trigger lever 32 is rotated clockwise about the shaft 33 by the spring 34.

This tri-lever 32 has pins 35 and 37 planted therein for switch control.

By rotating the trigger lever 32, the pin 35
First, the switch piece 36a is brought into contact with the switch 36b to give a signal to the motor control circuit indicating that the raising of the mirror 28 has been completed, thereby stopping the motor 1.

When the trigger lever 32 rotates further, the pin 37 then moves to the contact piece 38 of the shutter trigger switch.
a and 38b, and set the reference point in time for shutter operation. In substantially the same way, the lever 32 collides with the leading curtain tensioning lever 39, causing the leading curtain to start running.

In this state, the mirror drive lever 15 and the aperture lever 21 have the positional relationship shown in FIG. 4. As the ratchet gear 10 rotates, the shaft 14, pin 13, and shaft 40 are essentially aligned on a straight line.
In this state, the mirror drive lever 15
Even if a counterclockwise force is applied from the lever 25 and the narrowing lever 21, or a stronger force is applied, the arm 11 remains at the dead center with respect to the ratchet 10, so the arm 15 moves counterclockwise. Do not move in any direction. As a result, the mirror 28 remains in the raised position and the attached lens remains in the aperture position.

Next, after the exposure time has elapsed, the rear curtain runs and the shutter operation is completed, and the motor is rotated in the direction indicated by arrow b in FIG. 2 by a motor control circuit (not shown). This rotation allows the shutter to be set,
The film is wound. The rotation of this motor is transmitted to the trigger charge gear 5 and the ratchet gear 10 via a reduction gear 44 shown in FIG.

This counterclockwise rotation of the ratchet gear 10 causes the pin 13 of the link arm to follow this rotation. As a result, the mirror drive lever 15 and the aperture lever 21 return to the positions shown in FIG.
In this state, the mirror 28 is brought to the lowered position and the lens aperture is opened.

Before reaching this state, trigger lever 32 (second
(see figure), the pin 6 of the trigger charge gear 5 pushes the pawl 7, pushes the trigger charge lever 8, pushes the trigger lever 32 counterclockwise, and the part 32a is locked with the pawl 29, as shown in Fig. 2. be returned to position.

The restoration of the mirror, opening of the aperture, and setting of the trigger lever are performed at the initial stage of film winding and shutter charging. Therefore, even after these operations are completed, the ratchet gear 10 continues to rotate in the second direction, but the link arm only swings in accordance with the rotation of the ratchet gear, and the position of the lever, etc. does not change. .

When the film winding and shutter setting are completed, the motor 1 is stopped and the state before the start of photography is established.

Since the mechanism according to the present invention is constructed and operates as described above, the mechanism related to mirror drive or aperture drive is significantly simplified.

For example, it is necessary to keep the mirror mechanism lever and aperture lever in the positions shown in Figure 4 from the time the leading curtain runs until the rear curtain finishes running.In this case, the relationship between the link lever and the clutch is so-called. Since it is at dead center, there is no need to supply energy to the clutch to maintain its position, and it can maintain its position completely until the clutch rotates in the second direction.

In other words, the conventional concept required a mechanism such as mechanically detecting the end of the trailing curtain and releasing a hook to allow the mirror to descend, but the present invention uses a relationship between a ratchet gear and a link. Therefore, it is now possible to completely control the raising and lowering of the mirror or the aperture by rotating the motor in forward and reverse directions.
Reliable mirror drive or aperture drive is now possible with a simple mechanism.

[Brief explanation of the drawing]

1A and 1B are explanatory diagrams showing the internal arrangement of a single-lens reflex camera employing a mirror drive mechanism according to the present invention, FIG. 2 is a perspective view mainly showing the mirror control mechanism, and FIGS. 3 and 4 3 is a diagram showing the relationship between the mirror lever, the narrowing lever, and the ratchet gear. FIG. 3 shows the mirror in the lowered position, and FIG. 4 shows the mirror in the raised position. 1... Motor, 2... Upper pinion, 3... Lower pinion, 4... Reduction gear train, 5... Trigger charge gear, 6... Pin, 7... Pawl, 8... Lever,
9...Gear, 10...Ratchet gear, 11...
Link arm, 12... Spring, 13... Pin, 1
4...Axis, 15...Mirror drive lever, 16...
Shaft, 17, 18... Spring, 20... Pin, 21...
...Aperture lever, 22...Aperture lever spring, 23...Aperture lever on the lens side, 24...
...Pin, 25...Mirror up lever, 26...
Spring, 27...Mirror pin, 28...Mirror, 2
9... Hook, 30... Spring, 31... Hook shaft, 32... Trigger lever, 33... Shaft, 34...
...Spring, 35...Pin, 36, 38...Switch, 37...Pin, 39...Tension lever, 40...
...axis, 42...pin.

Claims (1)

[Scope of Claims] 1. A motor that rotates in forward and reverse directions, a ratchet gear to which the rotation of the motor is transmitted via a reduction gear train, and one end of which is biased to engage with the ratchet gear; A link arm receiving a driving force from a gear, a lever having the other end of the link arm pivotally supported and rotating by receiving a driving force from the ratchet gear via the link arm, and a habit of returning to an observation state are provided. , a mirror mechanism to which a driving force is applied from the lever against this returning behavior, and the motor rotates the ratchet gear in a first direction to push the lever via the link arm. Turn,
When the three points, the center of the ratchet gear, the engagement position of the ratchet gear and the link arm, and the pivot point of the link arm, are aligned, the mirror finishes rising and the shutter is closed. A drive mechanism for a motor drive camera configured to rotate the ratchet gear in a second direction to return the mirror. 2. A motor that rotates in forward and reverse directions, a ratchet gear to which the rotation of the motor is transmitted via a reduction gear train, and one end of which is biased to engage with the ratchet gear and receives driving force from the ratchet gear. A link arm, a lever on which the other end of the link arm is pivotally supported and which rotates by receiving a driving force from the ratchet gear via the link arm, are provided with a habit of returning to an open state, and are provided with a lever that resists this returning habit. and a narrowing lever to which driving force is applied from the lever, and by rotating the ratchet gear in a first direction by the motor, the narrowing lever is driven via the link arm, and the ratchet gear is rotated by the motor. The drive of the aperture lever is terminated when the three points, the center of the lens, the engagement position of the ratchet gear and the link arm, and the pivot point of the link arm are in a straight line, and after the shutter is closed, the A drive mechanism for a motor drive camera configured to rotate a ratchet gear in a second direction to return the aperture lever.