JP2949382B2 - Drive mechanism for aperture, lens and shutter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diaphragm, a lens and a shutter driving mechanism which sequentially drives a diaphragm blade, a focus adjusting lens and a shutter blade by using a single step motor as a driving source.

[0002]

2. Description of the Related Art Conventionally, a stepping motor has been widely used as a driving source of a mechanism member of a camera. When the stepping motor is used as a driving source, a driving pulse supplied to the motor is controlled by software to achieve the purpose. Suitable control characteristics can be obtained relatively easily.

[0003] As a control target of a camera,
It is well known that there are an aperture mechanism for setting the aperture diameter of the exposure aperture, a lens drive mechanism for driving the lens to the in-focus position, a shutter drive mechanism for opening and closing the exposure aperture, and the like. If these controlled objects are driven by independent step motors, it is possible to perform photographing utilizing the so-called aperture effect and shutter effect.

[0004]

However, a stepping motor is relatively large as a member for providing a small camera with a motor housing including a coil and a yoke, and is relatively large compared to other members. If an independent step motor is provided for each control target mechanism, there is a problem that the size and cost of the camera are increased, and a single step motor is used to drive various control targets. There was a request to share the source.

[0005]

SUMMARY OF THE INVENTION The present invention has been made based on such a background, and employs a relatively simple mechanism while using a single step motor as a drive source for an aperture mechanism and a lens drive. An object of the present invention is to provide an aperture, a lens, and a shutter drive mechanism that can drive a mechanism and a shutter drive mechanism.

In summary, the drive mechanism for the aperture, lens and shutter of the present invention comprises: a step motor capable of rotating forward and reverse; and a main drive member connected to the step motor and traveling with the rotation of the step motor. An aperture driving member for driving aperture blades for setting an exposure aperture diameter; an aperture engaging member for engaging the aperture driving member at a target position; a lens driving member for driving a photographic lens; A lens engaging member for engaging the member at a target position; a shutter driving member for driving a shutter blade for opening and closing the exposure opening; The aperture drive member and the main drive member such that the main drive member engages and drives the aperture drive member when the main drive member is actuated to one side from its origin position. Associating; after the main drive member drives the aperture drive member, the main drive member engages and drives the lens drive member when the main drive member passes through the origin position of the main drive member and operates on the other one; Associating the lens driving member with the main driving member as described above; and operating the shutter driving member when the main driving member returns to the home position after the main driving member drives the lens driving member. Achieve the goal.

Preferably, on the premise of the above, the exposure opening is fully opened at the initial position of the diaphragm driving member, and the driving of the diaphragm driving member by the main driving member can be omitted. I have.

According to another preferred embodiment, the drive mechanism for the aperture, the lens and the shutter according to the present invention includes: a stepping motor capable of rotating forward and backward; and a stepping motor connected to the stepping motor. A traveling main drive member;
A lens driving member that drives the taking lens; a lens engaging member that engages the lens driving member at a target position;
An aperture driving member for driving an aperture blade for setting an exposure aperture diameter; an aperture engaging member for engaging the aperture driving member at a target position; a shutter driving member for driving a shutter blade for opening and closing the exposure aperture An origin position of the main driving member is provided in an intermediate region of the travel range; and when the main driving member is operated to one side from the origin position, the main driving member engages the lens driving member. Associates the lens driving member with the main driving member so as to drive the lens driving member; after the main driving member drives the lens driving member, the lens driving member passes through the origin position of the main driving member and operates on the other side. Sometimes, the main driving member associates the main driving member with the main driving member such that the main driving member engages and drives the main driving member; after the main driving member drives the main driving member, the main driving member is driven. But To achieve the above object by the actuating the shutter drive member when returning to the point position.

[0009]

In other words, according to the present invention, when the main driving member operates to one side from its original position in response to the rotation of the step motor, the aperture driving member (lens driving member) is engaged with the main driving member. The vehicle travels and is engaged with the aperture engaging member (lens engaging member) at a target position. When the main drive member reverses and moves from the origin position to the other one, the lens drive member (aperture drive member) is engaged with the main drive member and travels to move to a target position and a lens engagement member (aperture engagement). ), And the positioning of both the diaphragm drive member and the lens drive member is completed. Since the shutter drive member operates to perform the exposure operation while the main drive member returns to the home position, it is possible to drive the aperture, lens, and shutter using a single step motor as a drive source. Become.

[0010]

FIG. 1 is a mechanism diagram showing one embodiment of the present invention. Reference numeral 1 denotes an output pinion of a known step motor, which is not shown in the figure. When a pulse is supplied to the step motor, the output pinion 1 changes to a pulse phase. Correspondingly rotate in both forward and reverse directions. The output pinion 1 is a large-diameter gear 2 constituting a two-stage gear 2.
a, and the small-diameter gear 2b constituting the two-stage gear meshes with a rack 3a formed on the main drive member 3.
The main drive member 3 has guide grooves 3b and 3c formed along its own running direction supported by pins 4 and 5 formed on the main plate, respectively. The rotation of the output pinion 1 is transmitted via the transmission train. The main drive member 3 travels in accordance with the rotation direction of the output pinion 1.

Next, reference numeral 6 denotes a first driving member for driving the aperture blade forming the exposure opening. First drive member 6
Are guide grooves 6a and 6 formed along their own traveling direction.
b is supported by pins 7 and 8 formed on the main plate, and is urged leftward by a spring 9 in the drawing.
The travel limit of the spring 9 is regulated by a stopper pin 10. In addition, in the attached drawings, in order to avoid complicating the drawings, springs indicate only the correction direction by arrows.

When the main drive member 3 travels rightward from the home position, the engagement pin 6d implanted near the tip of the engagement arm 6c formed at the lower edge of the first drive member 6 causes the main drive member 6 to move. The first drive member 6 is disposed at a position where it can be engaged with the engagement projection 3d formed on the upper edge of the first drive member 3 when the main drive member 3 travels to the right. The vehicle runs to the right against the spring 9 while being engaged with the piece 3d.

Reference numeral 11 denotes an aperture drive lever for transmitting the operation of the first drive member to the aperture blade. The aperture drive lever 11 is rotatably supported by a shaft 12 and rotates clockwise from a spring 13. Habits are given. A cam follower 11a that follows a cam edge 6e formed at the upper edge of the first drive member 6 is implanted in the aperture drive lever 11, and an aperture blade (not shown) is narrowed down when turning left around the shaft 12. In this way, it is associated with an aperture blade not shown.

Reference numeral 14 denotes a second drive member for extending the focus adjusting lens group 15. The second drive member 14 is a pin having guide grooves 14a and 14b formed along its own traveling direction formed on the main plate. The spring 18 is urged rightward in the drawing by a spring 18, and the travel limit of the spring 18 is regulated by a stopper pin 19. When the main drive member 3 travels to the left from the origin position, the engagement pin 14d implanted at the tip of the engagement arm 14c formed on the lower edge of the second drive member 14 is positioned above the main drive member 3. The main drive member 3 is disposed at a position where it can be engaged with the engagement protrusion 3e formed on the edge. When the main drive member 3 travels to the left, the second drive member 14 engages the engagement pin 14d with the engagement protrusion 3e. The vehicle travels left against the spring 18 while being engaged.

On the other hand, the focus adjusting lens group 15
It has a cam follower 15a that is driven by a cam edge 14e formed at the upper edge of the drive member 14, is urged by a spring 20, and is suppressed from moving in the left-right direction. When moving, the cam follower 15a follows the cam edge 14e while the spring 20 moves.
Is paid out against.

Reference numeral 21 denotes a ratchet lever which engages the first drive member 6 with a target aperture value. The ratchet lever 21 is rotatably supported by a shaft 22 on the main plate and is rotated leftward by a spring 23. Has been given. A click 22 for engaging a ratchet gear 6f formed on the lower edge of the first drive member 6 at the tip of the ratchet lever 21.
a is formed.

Reference numeral 24 denotes a ratchet lever which engages the second driving member 14 at a target focal position. The ratchet lever 24 is rotatably supported by a shaft 25 on the main plate, and is left-turnable by a spring 26. Has been given.
At the tip of the ratchet lever 24, a click 24a for engaging a ratchet gear 14f formed on the lower edge of the second drive member 14 is formed.

The shaft 27 provided on the ratchet lever 24
A clutch lever 28 constituting a one-way clutch is pivotally supported. The clutch lever 28 is provided with a left-turning property by a spring 29 having a sufficiently smaller force than the spring 26, and is provided with a shaft 30 provided on the ratchet lever 24. The left rotation relative to the ratchet lever 24 is regulated. Accordingly, when the release projection 3f formed on the upper edge of the main drive member 3 travels to the left at the position of the clutch lever 28, the clutch lever 28 independently turns clockwise against the spring 29 and simultaneously releases the release projection. When 3f travels rightward at the position of the clutch lever 28, the clutch lever 28 rotates counterclockwise around the shaft 25 with the ratchet lever 24. At this time, the ratchet lever 24
Arm 24b engages a pin 21b implanted in the ratchet lever 21 to turn the ratchet lever 21 clockwise against the spring 23.

Reference numeral 31 denotes a shutter drive lever for driving shutter blades for opening and closing the exposure opening. The shutter drive lever 31 is rotatably supported by a shaft 32 on the main plate and a spring 33. , And is associated with the shutter blades such that a shutter blade (not shown) is opened when the shutter drive lever 31 turns clockwise. However, in the initial state, the cam follower 31 provided at the tip of the shutter drive lever 31 is used.
a is a cam edge 14 formed on the lower edge of the second drive member 14
The right-handed rotation described above is suppressed by contact with g. A cam follower 31b is also provided at the other end of the shutter drive lever 31, and the cam follower 3 moves when the second drive member 14 travels left as the main drive member 3 travels left.
The cam edge 3g formed on the upper edge of the main drive member 3 before the 1a separates from the cam edge 14g enters the cam follower 31b to suppress the clockwise rotation of the shutter drive lever 31.

Therefore, the shutter drive lever 31 is turned clockwise by the urging force of the spring 31 only when the cam follower 31b falls on the concave cam 3h formed on the upper edge of the main drive member 3 when the main drive member 3 returns to the initial state. It is made to do.

Next, the operation of this embodiment will be described with reference to the above items and the time chart of FIG. In the time chart of FIG. 2, the horizontal axis indicates time and the vertical axis indicates the position of the main drive member.

In the initial state, all the mechanisms are in the state shown in FIG. 1. When a shutter button (not shown) is pressed from this state, a forward rotation pulse is supplied to the step motor, and the output pinion 1 rotates counterclockwise. Then, the rotation is transmitted to the main driving member 3 via the two-stage gear 2 and the rack 3a, and the main driving member 3 travels rightward in the drawing. When the main drive member 3 travels, the engagement projection 3d of the main drive member 3 engages with the engagement pin 6d provided on the first drive member 6, so that the first drive member 6 is also driven by the main drive member 3. And run right against the spring 9.

When the first drive member 6 travels to the right, the aperture drive lever 11 moves the shaft 1 against the spring 13 while the cam follower 11a follows the cam edge 6e of the first drive member 6.
Turn counterclockwise around 2 and narrow down the aperture blades (not shown). The pulse phase supplied to the stepping motor is inverted when the pitch number output pinion 1 corresponding to the target aperture value (the target aperture value corresponds to (a) in FIG. 2) rotates counterclockwise. To rotate the output pinion 1 clockwise. The elapsed time at the bottom of the valley of the characteristic curve in FIG. 2 is the stabilization time when the stepping motor is reversed.

Now, with the clockwise rotation of the output pinion 1, the main drive member 3 travels to the left in the drawing. At this time, the first drive member 6 engages the ratchet gear 6f with the ratchet lever 21. It stops at the target caliber position.

In the process in which the main driving member 3 travels to the left after passing through the origin position, the engaging projection 3e of the main driving member 3 engages with the engaging pin 14d of the second driving member 14, and the second driving Member 1
4 is moved to the left against the spring 18. In this process, when the main drive member 3 passes near the origin, the release projection 3f formed on the main drive member 3 engages the clutch lever 28. At this time, the clutch lever 28
Turn right alone against 9 Further, while the main driving member 3 travels to the left, the concave cam 3h passes through the cam follower 31b of the shutter drive lever 31, but the concave cam 3h
At the time when has passed the position of the cam follower 31b,
Still, one cam follower 3 of the shutter drive lever 31
1a is restrained by the cam edge 14g of the second drive member 14, and while the second drive member 14 travels further to the left, the cam edge 14g of the second drive member 14 is separated from the cam follower 31a by the time the main drive member 3a is separated. The concave cam 3h passes through the position of the cam follower 31b, and the cam edge 3g adjacent to the concave cam 3h contacts the cam follower 31b, so that the shutter drive lever 31 does not open.

When the second drive member 14 travels to the left, the cam follower 15a formed on the focus adjustment lens group 15 rides on the cam edge 14e of the second drive member 14, and the focus adjustment lens group opposes the spring 20. 15 is adjusted to adjust the focus. Then, when the pitch number output pinion 1 corresponding to the target focus position (the target focus position corresponds to (b) in FIG. 2) rotates clockwise, the pulse phase supplied to the step motor is inverted and output. Rotate pinion 1 counterclockwise. The elapsed time at the top of the characteristic curve in FIG. 2 is the stabilization time when the stepping motor is reversed.

The main drive member 3 travels rightward as the output pinion 1 rotates counterclockwise again.
At this time, the second driving member 14 is stopped at the target focal position because the ratchet gear 14f is engaged with the ratchet lever 24.

In this manner, the cam follower 31b of the shutter drive lever 31 moves while the main drive member 3 travels to the right.
Reaches the concave cam 3h from the cam edge 3g of the main drive member 3 at this point, since the cam follower 31a of the shutter drive lever 31 has already been released from the cam edge 14g of the second drive member 14, the main drive member 31b The cam follower 31b falls onto the concave cam and is turned clockwise by the spring 33. At this timing, the drive pulse supplied to the step motor is fixed for a time corresponding to the exposure second, and the rotation of the output pinion 1 also stops. The time width of (c) in FIG. 2 corresponds to the exposure time at this time.

When a time corresponding to the exposure time elapses, a drive pulse is again applied to the step motor, and the main drive member 3 travels further rightward and returns to the origin position. Then, while the main drive member 3 travels rightward, the cam follower 31b of the shutter drive lever 31 rides on the concave cam 3h of the main drive member 3 while riding on the shaft 32 against the spring 33.
And the shutter blade (not shown) is driven to close.

When the main drive member 3 returns to the home position in this manner, the release projection 3f formed on the main drive 3 engages the clutch lever 28, and the clutch lever 28 is moved together with the ratchet lever 24. Since it rotates counterclockwise around the shaft 25 against the spring 26, the ratchet lever 2
The engagement of the ratchet gear 14f by the click 24a of 4 is released, and the second drive member 14 travels rightward by the spring 18 and returns to its initial position. During the return process of the second drive member 14, the focus adjusting lens group 15 returns to its initial position by the biasing force of the spring 20 while the cam follower 15a moves down the cam edge 14e of the second drive member 14.

Further, the ratchet lever 24 is used as described above.
The arm 24b at the tip of the ratchet lever 24 is pinned to the pin 21b
While engaging the ratchet lever 21 with the spring 23.
The ratchet gear 6f is disengaged by the click 21a of the ratchet lever 21 and the first drive member 6 travels to the left by the spring 9 to return to its initial position. Return. During the return process of the first drive member 6, the aperture drive lever 11 is turned clockwise by the urging force of the spring 13 while the cam follower 11a follows the cam edge 6e of the first drive member 6, and the aperture blade (not shown) is fully opened. And the initial return operation of all the mechanisms is completed.

In the above, the second drive member 14 is driven after the first drive member 6 drives the aperture opening / closing lever 11.
In the example shown in FIG. 3, the focus adjusting lens group 15 is driven by the first driving member 6 as shown in FIG.
It is also possible to drive the aperture opening / closing lever 11 accordingly. The embodiment of FIG. 3 is completely the same as the embodiment of FIG. 1 except that the driving order of the aperture opening / closing lever 11 and the focus adjusting lens group 15 is reversed, and thus the common elements are used. The same reference numerals as those in FIG. 1 denote the same parts, and a redundant description will be omitted.

In the above, the main drive member 3, the first
Although an example in which the driving member 6 and the second driving member 14 travel linearly has been described, these mechanical members travel, for example, circumferentially along the periphery of the exposure opening in relation to the arrangement space. You can do it.

[0034]

As described above, according to the present invention, while employing a simple structure, a single stepping motor is also used as a driving source, and an aperture mechanism, a focus adjusting lens driving mechanism, and a shutter driving mechanism are used. Can be driven independently of each other, so that even if all the required control target mechanisms are driven by step motors, it is possible to effectively prevent an increase in manufacturing cost and an increase in mounting space.

As shown in FIG. 1, in the embodiment in which the lens drive mechanism is positioned after the aperture drive mechanism is positioned, the main drive member is moved from the origin position without driving the aperture drive mechanism. If the second driving member is immediately engaged and driven, the switching of the control program is simply performed without any mechanical alteration or addition, and the shutter blades can be directly used in the so-called program shutter control in which the aperture function is also used. It is also possible to respond.

[Brief description of the drawings]

FIG. 1 is a mechanism diagram showing one embodiment of the present invention.

FIG. 2 is a time chart showing the operation timing of the present invention.

FIG. 3 is a mechanism diagram showing another embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 output pinion of step motor 3 main drive member 3d engagement projection 3e engagement projection 3g cam edge 3h concave cam 6 first drive member 6d engagement pin 6f ratchet gear 11 aperture drive lever 14 second drive member 14d engagement Pin 14f Ratchet gear 14g Cam edge 15 Focus adjustment lens group 21 Ratchet lever 24 Ratchet lever 31 Shutter drive lever 31a Cam follower 31b Cam follower

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G03B 9/00-9/70 G03B 3/10

Claims (3)

(57) [Claims] 1. A stepping motor that can be rotated forward and backward, a main driving member that is connected to the stepping motor and travels with the rotation of the stepping motor, and an aperture drive that drives an aperture blade that sets an exposure aperture diameter. A member, a diaphragm engaging member for engaging the diaphragm driving member at a target position, a lens driving member for driving a photographing lens, and a lens engaging member for engaging the lens driving member at a target position And a shutter driving member for driving a shutter blade for opening and closing the exposure opening, and an origin position of the main driving member is provided in an intermediate region of the traveling range, and the main driving member is positioned one side from the origin position. After the main drive member drives the aperture drive member, the aperture drive member and the main drive member are associated so that the main drive member engages and drives the aperture drive member when actuated. The lens driving member and the main driving member are associated with each other such that the main driving member engages with and drives the lens driving member when passing through the origin position of the main driving member and operating on the other one. An aperture, a lens, and a shutter driving mechanism, wherein the shutter driving member is operated when the main driving member returns to the home position after the main driving member drives the lens driving member. 2. A driving mechanism for an aperture, a lens and a shutter according to claim 1, wherein an exposure opening is fully opened at an initial position of said aperture driving member.
A diaphragm, a lens, and a shutter driving mechanism, wherein driving of the diaphragm driving member by the main driving member can be omitted. 3. A stepping motor that can be rotated forward and backward, a main driving member that is connected to the stepping motor and runs with the rotation of the stepping motor, a lens driving member that drives a photographic lens, and a lens driving member. A lens engaging member for engaging the member at a target position, an aperture driving member for driving an aperture blade for setting an exposure aperture diameter, and an aperture engaging member for engaging the aperture driving member at a target position And a shutter driving member for driving a shutter blade for opening and closing the exposure opening, and an origin position of the main driving member is provided in an intermediate region of the traveling range, and the main driving member is positioned one side from the origin position. The lens driving member is associated with the main driving member so that the main driving member engages and drives the lens driving member when the lens driving member is operated, and the main driving member drives the lens driving member. After that, when the main drive member passes through the origin position of the main drive member and moves to the other one, the main drive member engages with and drives the aperture drive member, and the diaphragm drive member and the main drive member are connected to each other. A driving mechanism for driving a diaphragm, a lens, and a shutter, wherein the shutter driving member is operated when the main driving member returns to the original position after the main driving member drives the diaphragm driving member. .