JPH0711615B2 - Lens moving device - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a lens moving device for moving a lens unit such as a taking lens.

[Background of the Invention]

As an adjusting device for an imaging optical system, for example, an automatic focusing device, that is, an autofocus device (hereinafter abbreviated as AF) has been proposed in the past.

Conventionally equipped AF on commercially available cameras with AF
In the AF disclosed in the conventional proposal, the lens barrel is moved along the optical axis direction by the screw feed mechanism,
It has a structure in which the lens barrel is stopped at a predetermined position by causing a locking claw to jump into a serrated locking tooth provided integrally with the lens barrel, Is formed with a single-pitch screw, and the control of the locking claw is digitally controlled by an electronic circuit.

In order to improve the focusing accuracy in the AF having the above-described configuration, it is necessary to improve the accuracy of the stop position of the lens barrel, and in order to achieve this, for example, the screw pitch of the screw feed mechanism is made fine. In addition, it is necessary to take measures such as making the pitch of the locking teeth fine.

However, for the reasons described below, it has been found that there is a limit in implementing the above measures, and therefore, conventional AF cannot achieve a high-speed and highly accurate focusing operation.

(A) If the screw pitch of the screw feed mechanism is made fine, the moving speed of the lens barrel naturally decreases, so that quick focusing operation becomes impossible. Therefore, in order to prevent this, a speed-increasing gear for rotating the screw feed mechanism at a high speed is required, but if the number of gears increases, not only the efficiency of the power transmission system will decrease, but also the backlash of the gear will occur. However, the movement accuracy and the stop accuracy of the lens barrel also decrease. Further, as the screw pitch becomes smaller, the strength of the screw thread also decreases and the friction loss also increases.

(B) The finer the pitch of the locking teeth, the higher the positioning accuracy of the lens barrel, but the smaller the pitch of the teeth,
Since the teeth also become smaller, the mechanical strength also decreases, and therefore there is a limit to the reduction of the tooth pitch in terms of strength. Further, as described below, there is a limit to the reduction of the tooth pitch of the locking teeth from the relationship with the jumping time of the locking claws.

By the way, the jumping time required for the locking claws to jump between the locking teeth is 2 to 4 ms depending on the strength and energy of the parts allowed in a normal camera, so The passing time of one of the locking teeth (which is equal to one pitch of extension of the lens barrel) must be sufficiently longer than 4 ms. Therefore, for example, assuming that the time taken for one of the locking teeth to pass in front of the locking claw is 10 ms, and the subject distance is divided into 100 zones (that is, the distance that the lens barrel moves). Has a maximum value of 10
It takes 10 ms × 100 zones = 1 second for the lens barrel to perform the focusing movement corresponding to this object distance. Therefore, in the conventional camera with AF, there is a release time lag of up to 1 second from the time when the release button is pressed until the focusing operation ends, and therefore there are many opportunities to miss the shutter opportunity.

[Object of the Invention]

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a lens moving device capable of performing high-speed and high-precision lens movement control with respect to a signal for focus adjustment.

[Outline of Invention]

In order to achieve the above object, the present invention provides a first transmission mechanism for transmitting driving force at a first gear ratio to move a lens unit.
Driving force transmitting means, stopping means for stopping the lens unit, and a second speed ratio different from the first speed ratio for moving the position where the stopping means stops the lens unit. Second driving force transmitting means for transmitting the driving force, signal output means for outputting a signal for focus adjustment, and the first driving according to the amount of movement of the lens unit with respect to the signal from the signal outputting means. The lens moving device has a force transmitting means and an action amount determining means for determining an amount to be applied by the second driving force transmitting means.

Example of Invention

An embodiment of the present invention will be described below with reference to the accompanying drawings. The illustrated embodiment described below is an example in which the present invention is applied to a lens moving / positioning device of a non-interchangeable lens type variable power autofocus camera. In particular, in the camera of the present embodiment shown in FIG. 2, the lens movement for zooming, the lens movement for focusing, the film feeding, and the shutter driving are all performed by a single motor. The timing control of each operation of is configured to be performed by only one electromagnetic actuator (magnet),
The converter has a converter lens that is rotatably supported about an axis orthogonal to the axis of the lens barrel and is housed in parallel with the lens barrel. After returning, the converter lens is locked in the final retracted position.

FIG. 1 is a diagram showing a conceptual configuration of a lens moving / positioning device according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a lens barrel that is an object to be moved and positioned, and the lens barrel 1 has sawtooth-shaped locking teeth 1a that engage with a stop member to be described later. It is provided integrally. Reference numeral 2 denotes a screw shaft that is screwed into a female helicoid portion (not shown) in the lens barrel 1 to move the lens barrel 1 forward and backward in the direction of arrow f ₁ and the screw shaft 2 The gear 3 is fixed. Rotation is transmitted to the gear 3 from a differential device 4 as an operation start timing control means described later, and the differential device 4 is rotated from a motor 9 via a shaft 5, reduction gears 6 and 7, and a power transmission switching mechanism 8. Is transmitted. The screw shaft 2, the gear 3, and the helicoid portion in the lens barrel 1 constitute an object moving means for moving the lens barrel 1 (that is, an object).

Stop member moving / positioning means 11 is connected to the differential device 4 via a response means 10. The stop member moving / positioning means 11 is a device for feeding a stop member 12 described later by a predetermined distance in parallel with the object moving direction and positioning it at a predetermined position. For example, the structure described later in a concrete embodiment of FIG. Device.

Reference numeral 12 denotes a stop member that engages with the locking teeth 1a of the lens barrel 1 and stops the movement of the lens barrel 1 in the direction of arrow f ₁ , and the stop member 12 has an axis 12a in a direction orthogonal to the plane of the drawing. It is supported by the mounting portion 13 so as to be able to swing in the direction of the arrow f ₂ around the center. The attachment portion 13 is attached to the stop member moving / positioning means 11 via a mechanical connecting means or directly.

The stop member moving / positioning means 11 is a minute moving device for moving and positioning the stop member 12 in the direction of the arrow f ₃ by a predetermined minute distance, and the means 11 serves as a restraint releasing means and an operation start timing control means. Moving device 4 to response means 10
After being actuated via the transmission means, the operation is stopped from the operation control means 15 described later via the transmission means.

15 is a hydraulic control means for controlling the timing and the like to stop the movement of the arrow f ₃ the direction of the stop member 12 the locking tooth 1a stopping and engaged to timing member moving and positioning means 11, the acting kinematic control means 15 It is connected to the stop member 12 and the stop member moving / positioning means 11 via transmission means 16 and 17, respectively. In a specific embodiment described later, the operation control means 15 is composed of an electromagnetic actuator, that is, an electromagnetic magnet.

Reference numeral 18 denotes a control circuit that calculates the amount of movement to be given to the lens barrel 1 and controls the operation control means 15 based on the calculation result and controls the start and stop of the motor 9 and the reverse rotation. An output signal of the momentum detecting means 19 for detecting the momentum given to the screw shaft 2 and the stop member moving / positioning means 11 from the motor 9 is input to the motor. In the apparatus of this embodiment, the movement amount of the lens barrel 1 is determined by the operation start timing of the differential gear 4 as the operation start timing control means, the operation timing of the stop member 12, and the operation of the stop member movement / positioning means 11. It depends on the quantity and not on the timing of starting and stopping the motor 9.

The control circuit 18 divides the movement distance to be given to the lens barrel 1 into a first movement distance and a second movement distance based on the basic idea of the present invention, and uses a first signal representing the first movement distance. The stop member moving / positioning means 11 and the stop member 12 are controlled by applying the second signal representing the second movement distance to the operation control means 15, and thereby the lens barrel 1 is moved by a predetermined distance. .

Stop member moving / positioning means 11 and screw shaft 2 (that is,
The operation start timing with the object moving means) is determined by the differential device 4 as the operation start timing control means.

That is, when the power is transmitted from the motor 9 to the shaft 5, the differential device 4 first actuates the stop member moving / positioning means 11 via the responding means 10, and causes the stop member 12 to move through the means 11 to move the arrow. After slightly moving in the direction of f ₃ (that is, parallel to the moving direction of the lens barrel 1), after a predetermined time has elapsed, the screw shaft 2 is rotated to move the lens barrel 1 in the direction of the arrow f ₁ .

The minimum moving unit of the object moving means constituted by the screw shaft 2, that is, the lens barrel moving means (that is, the pitch of the serrated locking teeth) is set to 10 times the minimum moving unit of the stop member moving / positioning means 11. Therefore, the lens barrel is moved by the screw shaft 2 by a distance much larger than the moving distance of the stop member 12. The distance that the stop member 12 moves is determined by the stop member moving and positioning means 11,
The start of operation of the means 11 is determined by the differential device 4,
The operation end of 11 is determined by the operation control means 15. After all, the movement distance of the stop member 12 and the movement distance of the lens barrel 1 are determined by the operation timing of the operation control means 15.

FIG. 2 is an exploded perspective view showing a concrete embodiment of the device of the present invention. Note that in FIG. 2, parts corresponding to the conceptual configuration shown in FIG. 1 are indicated by the same reference numerals as in FIG.

In FIG. 2, 1 is a lens barrel, and 1a is the locking tooth fixed to the flange portion 1A of the lens barrel 1. An annular portion 1b is formed on the flange portion 1A, and the annular portion 1b is formed.
A helicoid ring 1c that is screwed into the screw shaft is inserted in the 1b. An axial groove (not shown) parallel to the axial direction is formed on the inner peripheral surface of the annular portion 1b, and an axial protrusion 1d provided on the outer peripheral surface of the helicoid ring 1c is slid on the axial groove. It is movably fitted. The helicoid ring 1c is engraved with a screw that engages with the inner peripheral surface screw shaft 2, and a flange portion 1e having a diameter larger than the inner diameter of the annular portion 1b is formed at the front end portion. Since the flange portion 1e is formed at the front end of the helicoid ring 1c as described above, the helicoid ring 1c
Is inserted from the front into the annular portion 1b. Therefore, as will be described later, after the lens barrel 1 is stopped by the stop member 12 in the feeding process of the lens barrel 1, the annular portion is
Only the helicoid ring 1c comes out from the inside of 1b and moves forward on the screw shaft 2.

One arm 20a of the blade drive lever 20, which is a member of the shutter blade drive mechanism, is pressed against the front end surface of the helicoid ring 1c by the force of the spring 21, and the force of the spring 21 causes the helicoid ring 1c to move within the annular portion 1b. Have been pushed into. Therefore, the helicoid ring 1c does not slip out of the annular portion 1b while the lens barrel 1 is moving forward, but after the lens barrel 1 is stopped by the stop member 12, the helicoid ring 1c is annular on the screw shaft 2. Get out of section 1b and move forward.

The blade drive lever 20 is a support pin provided on the lens barrel 1.
It is rotatably supported by 1f and is urged in the counterclockwise direction by a spring 21 fitted to the support pin 1f.

A flange 1A of the lens barrel 1 is also provided with a pin 1g projecting in the vicinity of the support pin 1f in parallel with the screw shaft 2. The pin 1g is a blade in the shutter blade drive mechanism shown in FIG. The opening lever 38 is rotatably supported. The shutter blade drive mechanism will be described later. Further, a window 1h is provided through the flange portion 1A of the lens barrel 1, and a projection 1i is formed on the inner peripheral edge of the window 1h. The window 1h and the projection 1i
Is related to the converter lens holding frame described later, and will be described later.

A gear 3 is fixed to the screw shaft 2, and rotation is transmitted to the gear 3 from a differential device 4 as an operation start timing control means.

As shown in FIG. 2, the differential device 4 has a driven member 22 having an externally toothed gear portion that meshes with the gear 3, and transmits the rotation to the driven member 22 with a predetermined time delay and the driven member 22.
Before transmitting the rotation to the driving member 23 for actuating the stop member moving / positioning means 11, a spring 24 biasing the driving member 23 toward the driven member 22 is provided. There is. The driven member 22 is a gear portion that is constantly meshed with the gear 3.
22a and a spiral end surface cam 22b. The end surface cam portion 22b includes a spiral cam surface 22c and a stopper portion 22.
d and are formed. On the other hand, the drive member 23 has the cam surface 22c.
23a abutting against the gear 6 and an engaging portion 23b engaging with the gear 6
And a flat surface 23c (a surface orthogonal to the axis) that engages with the follower 25c corresponding to the responding means 10, and is integrated with the gear 6 in the rotational direction by the engagement of the engaging portion 23b. Is configured to rotate and move freely in the axial direction. That is, the engaging portion 23b is formed on the peripheral wall surface of the shaft hole of the gear 6.
Is formed so as to be fitted so as to be movable in the axial direction. The gear 6 and the driving member 23 are connected by inserting the engaging portion 23b into the axial groove. Engaging part 23
The axial length of b is designed to be longer than the axial movement distance of the driving member 23. Therefore, even when the driving member 23 moves to the position farthest from the gear 6, the engaging portion 23b moves to the gear 6 side. It does not come out from the shaft hole. The gear 6 is a gear driven by the motor 9 (FIG. 1) via the power transmission switching mechanism 8 and the gear 7. Further, in FIG. 2, the driven member 22
Although the shaft for supporting the driving member 23 and the driving member 23 is not shown, the driven member 22 and the driving member 23 are loosely fitted to the supporting shaft, and the gear 6
Is fixed.

Reference numeral 19 denotes the momentum detecting means shown in FIG. 1. In this embodiment, the means 19 is an encoding plate 19a which rotates together with the gear 6.
And a photo interrupter 19b that generates a pulse corresponding to the black and white pattern on the encoding plate 19a.

Next, referring to FIG. 2, the components corresponding to the stop member moving / positioning means 11 associated with the driving member 23 of the differential device 4 and the components corresponding to the response means 10 of FIG. Explain.

In FIG. 2, reference numeral 25 denotes a toothed sector arm which is arranged near the driving member 23 and is supported so as to be rotatable about a shaft 25a in a direction orthogonal to the screw shaft 2. The toothed sector arm 25 is provided with a pin 25b protruding parallel to the shaft 25a at a position farther than the shaft 25a, and the pin 25b is a lateral protrusion 26a of a stop member supporting / moving member 26 described below.
Is abutted on. The toothed sector arm 25 is also provided with a follower 25c protruding parallel to the pin 25b.
25c is in contact with the flat surface 23c of the drive member 23 as already described.

The stop member supporting / moving member 26 is supported by a structural member such as a camera body by three supporting / sliding guide pins 26b to 26d parallel to the screw shaft 2 and can move in a direction parallel to the pins. ing. One of the pins 26b-26d 26
The spring 27 fitted in d is compressed between the outer surface of the member 26 and the surface of the structural member such as the camera body, and the spring 27 causes the member 26 to move in the direction of the arrow f _{4 in} the figure (that is, the screw shaft 2). It is always energized (in the direction parallel to the front of the camera).

Therefore, the pin 25b of the toothed sector arm 25 is also biased upward in FIG. 2, so that the toothed sector arm 25 is rotated by the force of the spring 27 via the pin 25b about the shaft 25a in FIG. It is urged in the time direction. Therefore, the follower
25c is pressed against the flat surface 23c of the drive member 23 by the force of the spring 27, but unless the drive member 23 moves axially, the toothed sector arm 25 is kept in a non-rotating state.

A stop member supporting pin 26e for rotatably supporting the stop member 12 is provided on the stop member supporting / moving member 26, and the pin 26e rotates relative to the hole 12b at the base end of the stop member 12. It is designed to be inserted as much as possible. A spring 28 for biasing the stop member 12 in the clockwise direction in FIG. 2 is fitted on the pin 26e.

A claw member 29 for indexing (positioning) the toothed sector arm 25 to an arbitrary rotation angle position is provided by the sector arm 25.
Are arranged close to the outer peripheral portion of the. The pawl member 29 has an axis 29a parallel to the axis 25a of the sector arm 25, is supported by a stationary structural member so as to be rotatable about the axis, and is biased by a spring 30 in the arrow direction. ing. Locking claws that engage with the teeth of the sector arm 25 are formed at the tips of the claw members 29, and when the locking claws are inserted between the teeth of the sector arm 25, the sector arm 25 rotates. 25a
Even if the sector arm 25 can rotate counterclockwise about the center, the rotation of the sector arm 25 is blocked by the claw member 28.

An arm 29b is projectingly provided on the shaft 29a, and the arm 26b is provided with a spring 30.
Is pressed against the pin 31a of the second lever 31 described later. The second lever 31 is a member that overcomes the force of the spring 30 and operates the pawl member 29 counterclockwise (that is, in a direction in which the pawl member 29 is engaged with the teeth of the toothed sector arm 25).

As is apparent from the above description, the stop member 12 is moved in a direction parallel to the screw shaft 2 and the stop member 12 is moved to an arbitrary position.
Stop member moving and positioning means 11 for positioning 12
Is a toothed sector arm 25 and its integral pin 25b
In addition, the follower 25c, the stop member supporting / moving member 26, the spring 2
7 and various members such as a claw member 29 for indexing the toothed sector arm 25 to an arbitrary rotation angle position. The mounting portion 13 and the mechanical connecting means 14 shown in FIG.
Although it may not be necessary, it may be necessary when the stop member moving / positioning means 11 has an electrical configuration.

Further, in order to interlock the stop member moving / positioning means 11 and the differential device 4, the responding means 10 is a follower 25c integral with the toothed sector arm 25 in the embodiment of FIG.

Next, a magnet (that is, an electromagnetic actuator) as the operation control means 15 shown in FIG.
The structure as transmission means 16 and 17 for connecting the stop member 12 and the stop member moving / positioning means 11 will be described.

In Figure 2, 32 is a magnet as operation control means 15 of FIG. 1, the magnet 32 when energized (ON) has a plunger 32a that is moved in the direction of arrow f _5. The plunger 32a is adapted to the magnet 32 is moved in the direction of arrow f ₆ by later of the first lever spring when de-energized state (OFF).

The transmission means 16 and 17 are composed of a first lever 33 that is moved by the magnet 32, and a second lever 31 and a third lever 34 that are moved by the first lever 33.

The first lever 33 is supported by a structural member of the camera so as to be rotatable about a shaft 33a, and has four arm portions, first to fourth. The first of these arms 33
A pin 33c engaged with the plunger 32a is fixed to the tip of b, and a pin 33e engaged with the first pin 31b fixed to the second lever 31 is fixed to the tip of the second arm 33d. Has been done. In addition, the third arm 33f is one arm 3 of the third lever 34.
The fourth arm portion 33g is engaged with the pin 4b, and the fourth arm portion 33g is engaged with the pin 40b fixed to the blade releasing claw 40 which is a part of the shutter driving mechanism. Then, the first lever 33 is always biased in the clockwise direction about the shaft 33a by the spring 35 locked to the fourth arm portion 33g. Accordingly, the first lever 33 so the plunger 32a is not moved in the direction of arrow f ₅ when the magnet 32 is not energized, the shaft by the force of the spring 35
It is rotated clockwise around 33a.

The second lever 31, which constitutes the transmission means 17 together with the first lever 33, has a shaft 31c orthogonal to the screw shaft 2 and is supported by a structural member so as to be rotatable about the shaft 31c. ing. The second lever 31 has pins 31a and 3 fixed to the tips of two arm portions 31d and 31e extending outward from the shaft 31c.
One 31a of the 1b is engaged with the arm 29b of the claw member 29, and the other pin 31b is the pin 33e of the second arm 33d of the first lever 33.
Is engaged with.

On the other hand, the third lever 34, which constitutes the transmission means 16 together with the first lever 33, has a shaft hole 34 having an axis parallel to the screw shaft 2.
It has a boss portion 34c provided with b and is rotatably supported by the structural member by inserting a pin (not shown) of the structural member into the shaft hole 34b. The third
The lever 34 has two arms 34a and 34b as shown,
One arm 34a is engaged with the third arm portion 33f of the first lever 33, and a pin 34e engaged with the arm portion 12c of the stop member 12 is fixed to the tip of the other arm 34d.

The above is the schematic structure of the mechanical structure portion of the lens moving / positioning device in the camera of the present embodiment. The locking means associated with the differential device 4 and the lens barrel 1 in the lens moving / positioning device is described below. Since the camera of this embodiment is provided, the second embodiment of the locking means will be described below.
This will be described with reference to FIGS. 3, 3 and 4.

As described above, the camera according to the present embodiment is provided with the converter lens which is rotatably supported around the axis of the lens barrel and is parallel to the lens barrel. The lens barrel is configured to automatically return to the most retracted position immediately after the photographing is finished and to be locked at the position.

2 to 4, reference numeral 36 denotes a converter lens holding frame, and the holding frame 36 includes a support shaft 36a in a direction orthogonal to the axis of the lens barrel 1 and an annular holding frame main body for holding the converter lens. 36b, the support shaft 36a, and the holding frame main body 36b
And an arm portion 36c that communicates with the. The converter lens holding frame 36 has a lens barrel 1 as shown in FIG.
So that the surface of the holding frame main body 36b faces the outer peripheral surface of the lens barrel 1 (ie,
The converter lens holding frame 36 is housed in the camera body so that it is substantially parallel to the lens barrel 1, and the support shaft 36a
The force applied to the spring hooking portion 36d protruding from the arm portion 36c from the torsion spring 37 fitted in the arm is always biased clockwise around the support shaft 36a in FIG. The converter lens holding frame 36 is the flange portion 1A of the lens barrel 1.
The holding frame body 36b is provided with a chevron-shaped engaging portion 36e that engages with the protrusion 1i on the inner peripheral edge of the window 1h. The engaging portion 36e has two side portions that are gently inclined with respect to the end surface of the holding frame main body 36b, and as shown in FIG.
When 36 is removed from the movement path of the lens barrel 1 (that is, the lens barrel 1 is in the most retracted position), the intersection of both sides (that is, the maximum protruding portion of the engaging portion 36e) ) Is located in front of the projection 1i of the lens barrel and is slightly inside (position closer to the outer peripheral surface of the lens barrel 1) and engages with the projection 1i.
e is designed.

Therefore, in the state of FIG. 3, the lens barrel 1 is constrained or locked by the converter lens holding frame 36,
Even if an impact is applied to the lens barrel 1, the lens barrel 1 does not project forward.

Further, in the state shown in FIG. 3, since the converter lens holding frame 36 is pressed against the lens barrel 1 by the spring 37, the load on the screw shaft 2 becomes large, which prevents the differential device 4 from malfunctioning. can do. That is,
Since the driving member 23, which is one member of the differential device 4, is pressed against the cam surface 22c of the driven member 22 by the spring 24, if the load of the driven member 22 is small when the driving member 23 is started, the driving member 23 is driven.
The driven member 22 may be rotated before the protruding portion 23a of 23 reaches the lowest position of the cam surface 22c of the driven member 22.
As shown in the figure, if the lens barrel 1 is constrained by the converter lens holding frame 36, the load of the driven member 22 becomes very large, so that the driven member is moved during the axial movement of the driving member 23.
22 is prevented from being rotationally driven by the driving member 23, and as a result, the differential device 4 is initially operated (that is, after the stop member moving / positioning means 11 is first operated, the screw shaft which is the lens moving means). The operation of transmitting rotation to 2) can be caused.

FIG. 4 shows a state in which the lens barrel 1 is largely extended forward at the time of long-focus photography, and the converter lens holding frame 36 is inserted immediately after the lens barrel 1 accordingly. In this case, since the converter lens holding frame 36 is biased in the clockwise direction by the force of the spring 37, it is automatically inserted immediately after the lens barrel as the lens barrel 1 moves forward.
(Note that the motor power can be used to insert the converter lens holding frame 36 immediately after the lens barrel 1.) In the camera of this embodiment, the lens barrel 1 is the first lens after the end of shooting and at the time of non-shooting. As shown in FIG. 3, the converter lens holding frame 36 is locked in the most retracted position, and is housed substantially parallel to the side surface of the lens barrel 1. It is possible to eliminate the drawbacks of the (camera) such that the lens barrel is likely to collide with another object and the thickness of the camera body is considerably large.

Further, in the camera of this embodiment, since the lens barrel automatically returns to the most retracted position after the end of shooting, there is less risk of light leaking into the lens barrel, and moreover there is no damage to the lens barrel. Since there is little danger, it is not necessary to complicate the light-shielding structure of the lens barrel or particularly increase the rigidity of the lens barrel. Therefore, the weight and manufacturing cost of the lens barrel and the camera body are not increased.

Next, the structure of the shutter drive mechanism which is attached to the object moving and positioning apparatus of the present invention and which is mounted on the camera,
This will be described with reference to FIG.

In FIG. 5, 1c is the helicoid ring shown in FIG. 2, and 20 is the blade drive lever. The blade drive lever 20 has two arms 20a and 20b, one arm 20a is engaged with the front end face of the helicoid ring 1c, and the other arm 20b is engaged with one arm 38a of the blade opening lever 38. ing. Blade opening lever 3
8 is a shaft hole 38b into which the pin 1g fixed to the lens barrel 1 is fitted
Has a boss portion 38c provided with
It is urged counterclockwise around. A pin 38e to be inserted into a boss hole 40a of a blade releasing claw 40 (see FIG. 2) is fixed to the tip of the other arm 38d of the blade opening lever 38, and a blade 41 is fitted into the pin 38e so as to move the blade. Release claw 4
In 0, a force in the clockwise direction centering on the pin 38e is applied. The blade releasing claw 40 has a pin 40b which engages with the fourth arm 33g of the first lever 33 as shown in FIG. 2, and when the first lever 33 is actuated by the force of the spring 35, it is a boss. arrow f ₇ direction of FIG. 2 around the hole 40a, that is, rotated counterclockwise.

A blade drive shaft 42 having an arm 42a that engages with the blade releasing pawl 40 is provided near the blade releasing pawl 40. Blade drive shaft 42
Has a shaft portion 42b parallel to the screw shaft 2 and is rotatably supported by the lens barrel 1 at the shaft portion 42b.
A spring 43 hung on the arm 42c urges the shaft 42b in the clockwise direction about the shaft 42b. Another arm 42d is formed at the other end of the shaft portion 42b, and the tip of the arm 42d is
A pin 42e inserted into a slot 44a penetrating the shutter blade 44 is provided in a protruding manner. A rotation center hole 44b into which a pivot pin (not shown) is inserted is formed in the shutter blade 44,
The shutter blade 44 is adapted to be rotated around the rotation center hole 44b.

Next, with reference to FIG. 6, a control circuit, a detector and the like mounted on the camera of this embodiment will be described. The sixth
The circuit shown includes all the circuitry and detectors associated with controlling the magnet 32 of FIG.

In FIG. 6, 101 is a release button (not shown)
A switch that is closed when the stroke operation is performed, a switch 102 that is closed only when performing long-focus photography, and a switch 103 that is closed when the release button is pushed to the second stroke. 105 to 107 are pull-up resistors, 109 to 111 and 128 and 129 are inverters, 11
3 to 115 are latch circuits composed of RS flip-flops, 116 is a known distance measuring circuit, 117 and 122 are AD conversion circuits,
125 to 127 are digital comparators, 103 and 104 are AND gates, 121 is a known photometric circuit, 138 is an OR gate, 19 is the momentum detector shown in FIGS. 1 and 2, and 139 is an exciting current for the magnet 32. A transistor 118 for turning on and off calculates a lens required movement amount from the distance measurement value binarized in the AD conversion circuit 117, and divides the lens required movement amount into an upper two digits and a lower two digits. A decoder 119 for generating an output signal for obtaining a proper exposure by calculating the required moving amount of the blade opening from the two output signals and the photometric signal binarized in 122, counts the pulse signal generated by the momentum detector 19. It's a counter. 140 is the decoder 1
A digital comparator 12 based on the first output signal of 18
An address register for storing the reference value in 5 and a cue register for storing the reference value in the digital comparator 126 based on the second output signal of the decoder 118, 141
Reference numeral 2 is an exposure register that stores a reference value in the digital comparator 127 based on the third output signal of the decoder 118. The address register 140 stores the lower two digits (that is, a minute movement amount) of the required lens movement amount, and the chome register 141 has the upper two digits (that is, a large movement amount) of the lens required movement amount. Is to be set.

Next, the operation of each part in the camera of this embodiment will be described with reference to FIGS.

Before the start of shooting (that is, when not shooting), the lens barrel 1 is held in the most retracted position by the converter lens holding frame 36 as shown in FIG. 3, and the helicoid ring is held. Reference numeral 1c denotes an annular portion 1b of the lens barrel 1 with only the flange portion 1e protruding from the annular portion 1b.
Has been inserted inside.

In addition, the projection 23a of the drive member 23 of the differential device 4 has the driven member 22
Is brought into contact with the highest position a of the cam surface 22c of the drive member 23
Is stopped and the follower 25c of the toothed sector arm 25
Is pressed against the flat surface 23c of the drive member 23 by the force of the spring 27. At this time, the toothed sector arm 25 stops in its own original position by the upward reaction force from the drive member 23, and the pawl member 29 and the second lever 31 force the force of the spring 35 because the plunger 32a is in the off state. Thus, the claw member 29 is held in the state of being rotated left and the second lever 31 being rotated in the right direction.
In this case, since the driving member 23 is stopped at the highest position in FIG. 2, the follower 25c of the toothed sector arm 25 is
Also rests in the highest position, so that the pin 25b is pushed down to the lowest position by the drive member 23. Therefore, the stop member supporting / moving member 26 is also stationary while being pushed down to the lowest position (that is, the origin position) by the pin 25b in FIG. 2, and the spring 27 is in the most compressed state. ing. Therefore, the stop member
12 is also stationary at its origin. Also,
At this time, the third lever 3 engaged with the arm 12c of the stop member 12
Since the pin 34e of 4 is not given the force for urging the arm portion 12c rightward in FIG. 2 from the first lever 33, the stop member 12 is separated from the locking tooth 1a by the force of the spring 28. Is held in a closed position. On the other hand, the magnet that is the operation control means
Since 32 is in a non-excited state, the plunger 32a has a second
In the figure, the force in the arrow f ₅ direction is not applied, and the first lever 33 is in the state of being biased in the arrow direction of the spring 35 by the force of the spring 35.

On the other hand, in the shutter drive mechanism, since the helicoid ring 1c does not largely protrude from the inside of the annular portion 1b of the lens barrel 1, the arm 20a of the blade drive lever 20 is in the most lowered state in FIG. Therefore, the other arm 20b of the lever 20 is held in the uppermost position in FIG. Therefore, the arm of the blade opening lever 38
38d and the blade release claw 40 integrated therewith are stationary at the position most rotated in the direction of the arrow by the force of the spring 39. In addition, the blade drive shaft 42 engaged with the blade release claw 40 has a spring 43.
The shutter blade 44 holds the shutter in the closed state by being rotated by the force in the arrow direction. At this time, of course, the motor 9 (FIG. 1) is stopped.

The operation of each unit when the above-described state is changed to long-focus imaging will be described below.

Prior to the photographing operation, when a long-focus photographing mode is selected by operating a photographing mode switching knob (not shown) for long-focus photographing, the switch 102 in FIG. 6 is turned on.

Next, when the field of view is adjusted to the subject and the release button (not shown) is pushed down to the first stroke to start photographing, the switch 101 shown in FIG. 6 is turned on. Therefore, an output is generated in the inverter 109, and in response to this, the latch circuit 113
Produces output.

When an output is generated from the latch circuit 113, the distance measuring circuit 116 and the photometric circuit 121 operate to perform distance measurement and photometry by a known method. The distance measurement result and the photometry result are respectively the AD exchange circuit 11
It is binarized by 7 and 122. The binarized distance measurement value is applied to the decoder 118 to be converted into a lens required movement amount corresponding to the distance measurement result and a blade opening required movement amount corresponding to the photometry result, and the lens required movement amount is predetermined. Method is divided into a large movement amount and a minute movement amount, and a first output signal representing the minute movement amount is input to the address register 140,
The second output signal representing the large movement amount is the chome register 141.
Entered in.

At this time, as described above, since the switch 102 is closed, an output is generated in the inverter 110, and since an output is also generated in the latch circuit 114, an input signal is input to the decoder 118 and the decoder 118 is long. Performs focus shooting calculations. Therefore, the decoder 118 outputs to the claw register 141 a signal representing the large distance movement amount required for long focus photography.

On the other hand, to the address register 140, a signal representing the minute distance movement amount necessary for the lens minute movement of the lens necessary movement amount is input regardless of the long-focus photography and the short-focus photography.
The signal is stored in the register 140 as a reference value for the minute movement distance.

Then push the relays button down to the second stroke,
Since the output is generated from the latch circuit 115, the AND gate 103 becomes conductive (at this time, the output is generated in the inverter 128 because the output is not generated in the digital comparator 125). Therefore, the output is generated in the OR gate 138, and as a result, , The transistor 139 becomes conductive and the magnet 32 is excited.

When the magnet 32 is energized, the first lever 33 so the plunger 32a is attracted in the arrow f ₅ direction Figure 2 is rotated about the axis 33a in a counterclockwise direction against the force of the spring 35,
As a result, the pin 31a of the second lever 31 descends and the claw member 29
Springs 30 away from the teeth of the toothed sector arm 25.
The sector arm 25 is rotated by the force of to make the sector arm 25 rotatable. On the other hand, the arm portion 33f of the first lever 33 has the third lever 34
The arm 34a of the third lever 34a is pushed to the front side in FIG.
Is rotated clockwise about the shaft hole 34b, the pin 34e pushes the arm 12c of the stop member 12, and as a result, the stop member
Since 12 is rotated in the counterclockwise direction in FIG. 2 about the shaft hole 12b, the claw at the tip of the stop member 12 engages with the stop tooth 1a of the lens barrel 1 to temporarily move the lens barrel 1 to bound.

After that, the motor 9 (FIG. 1) is energized and the motor 9
Is driven in the forward rotation direction and the power transmission switching mechanism 8
The gear 6 is rotated in the clockwise direction in FIG.

When the gear 6 rotates in the clockwise direction, the projection 23a of the member 23 rotates in the clockwise direction while the driving member 23 rotates in the clockwise direction, and the cam surface 2 of the driven member 22 moves.
As it slides down on the position 2c from the position a to the position b, the driving member 23 rotates and moves axially toward the driven member 22. At this time, as described above, the converter lens holding frame for the lens barrel 1 is used as the load of the driven member 22.
Since the restraining force of 36 acts, the driven member 22 will not be rotationally driven during the axial movement of the driving member 23.

When the driving member 23 starts to move in the axial direction toward the driven member 22, the force pushing the follower 25c upward in FIG. 2 (that is, the force pressing the spring 27 downward) gradually. Due to the decrease, the spring 27 begins to expand and the stop member supporting and moving member 26 is moved upward in FIG. 2 (in front of the camera).
To move. When the member 26 begins to move in the direction of the arrow f ₄ , the pin 25b pressed onto the protrusion 26a of the member 26 is also lifted up, so that the toothed sector arm 25 is centered on its own axis 25a. As shown in FIG. 2, rotation starts in the counterclockwise direction.

In this case, the movement amount of the stop member supporting / moving member 26 in the direction of arrow f ₄ and the rotation angle of the toothed sector arm 25 are detected as the rotation angle of the gear 6 by the momentum detecting means 19 as an electric pulse signal. Therefore, the momentum detecting means 19 shown in FIG.
Then, a pulse signal corresponding to the movement amount of the member 26 is applied to the input signal terminal of the digital comparator 125. Therefore, when the value of the pulse signal becomes equal to the reference value, the output of the digital comparator 125 is generated and the output of the comparator 125 is applied to the inverter 128. Therefore, the output of the inverter 128 disappears, and the AND gate 1
03 becomes non-conductive, the output of the OR gate 138 disappears, and the transistor 139 turns off, so that the magnet 32 is demagnetized. Therefore, the plunger 32a by the force of the spring 35 is pulled out in the direction of arrow f _6, the first lever 33 is shaft 3
It is rotated clockwise around 3a. Therefore, the second
Since the lever 31 is rotated clockwise about the shaft 31c, the arm 29b of the claw member 29 is pushed up by the pin 31a of the second lever 31, and as a result, the claw member 29 is rotated counterclockwise about the shaft 29a. It rotates and engages with the tooth of the sector arm with a claw tooth at the tip thereof to stop the rotation of the sector arm 25. Therefore, the upward movement (movement in the direction of arrow f ₄ ) of the pin 25b of the sector arm 25 is also stopped, so that the movement of the stop member supporting / moving member 26 in the direction of arrow f ₄ is also stopped, and the stop member 12 is moved in the direction of arrow f ₄ Further, the toothed sector arm 25 is positioned at a position moved from the original position by a distance corresponding to the rotation angle.

On the other hand, since the arm 33f of the first lever 33 also rotates clockwise in response to the clockwise rotation of the first lever 33 due to the demagnetization of the magnet 32, the third lever 34 moves the shaft by the force of the spring 28. The stop member 12 is rotated counterclockwise about the hole 34b, and the stop member 12 is also rotated clockwise about the shaft hole 12b by the force of the spring 28. Therefore, the claw at the tip of the stop member 12 is disengaged from the stop tooth 1a, and the lens barrel 1 is prepared to move forward.

When the projection 23a of the driving member 3 reaches the point b on the cam surface 22c of the driven member 22 after the above-described operations, the axial movement of the driving member 23 is blocked and the driven member 22 is driven.
The screw shaft 2 starts rotating in the clockwise direction together with 23, and as a result, the screw shaft 2 starts rotating through the gear 3, and the lens barrel 1 is fed forward. When a forward thrust is applied to the lens barrel 1 by the screw shaft 2, the protrusion 1i (see FIG. 3) moves forward beyond the maximum protrusion of the engaging portion 36e of the converter lens holding frame 36, and as a result, the converter lens The holding frame 36 is released from the constraint on the lens barrel 1.

Then, in the process of advancing the lens barrel 1 to the position shown in FIG. 4 necessary for long-focus photography, the covert lens holding frame 36 is also rotated about the support shaft 36a by the force of the spring 37,
Finally, it is positioned in the lens barrel 1 immediately after the main lens.

In the process of the lens barrel 1 moving forward on the screw shaft 2, the amount of rotation given to the screw shaft 2 is detected as an output pulse of the momentum detecting means 19, and the output pulse is applied to the input terminal of the digital comparator 126. It Then, when the number of input pulses to the digital comparator 126 becomes equal to the number of reference pulses stored in the claw register 141 in advance, an output is generated in the digital comparator 126, and as a result, the AND gate 104 is turned on and the transistor 139 is turned on. , Magnet 32 is excited. When the magnet 32 is energized, the plunger 32a is retracted in the arrow f ₅ direction, the first lever 33 is rotated overcoming the force of the spring 35 in a counterclockwise direction, the rotation of the first lever 33 The third lever 34 is rotated clockwise about the shaft hole 34b. Therefore, the pin 34e pushes the arm 12c of the stop member 12, and the stop member 12c
Is rotated counterclockwise about the shaft hole 12b and the claw at the tip of the stop member 12 jumps between the locking teeth 1a to stop the forward movement of the lens barrel 1. At this time, the pressing of the first lever 33 on the pawl member 29 is released, but the pawl member 29 is engaged with the teeth of the sector arm 25, and therefore is not rotated clockwise by the spring 30.

The completion of the forward movement of the lens barrel 1 means the completion of the operation of enlarging the photographing magnification and the focusing operation in the camera of this embodiment.

After the lens barrel 1 stops moving forward, the motor 9 continues to rotate and the screw shaft 2 also continues to rotate.
Forward thrust is applied from the resulting helicoid ring
1c overcomes the force of the spring 21 and slips forward from the inside of the annular portion 1b to advance on the screw shaft 2.

On the other hand, when the helicoid ring 1c projects forward from the annular portion 1b, the blade driving lever 20 is rotated clockwise about the pin 1f by the helicoid ring 1c in FIGS. The blade drive opening lever 38 that is movably fitted is rotated clockwise about the pin 1g (that is, the shaft hole 38b) in FIG. Further, since the blade drive 42 is rotated counterclockwise about the shaft 42b via the blade release claw 40 by the rotation of the blade opening lever 38, the shutter blade 44 is moved via the pin 42e of the blade drive shaft 42. It is rotated about the rotation center 44b. Then, the rotation amount of the shutter blade 44 is detected as an output pulse of the momentum detecting means 19, and the output pulse is applied to the input terminal of the digital comparator 127. Then, when the number of input pulses to the digital comparator 127 becomes equal to the number of reference pulses stored in advance in the exposure register 142, an output is generated and the transistor 139 is turned off,
The magnet 32 is demagnetized. When the magnet 32 is demagnetized, the first lever 33 is rotated clockwise by the urging force of the spring 35, and the tip of the arm 33g pushes the pin 40b of the blade releasing claw 40 to the right in the figure. The blade release claw 40 is rotated counterclockwise. By rotating the blade release claw 40 counterclockwise, the engagement of the blade drive shaft 42 with the shaft portion 42b is released (see FIG. 5), and the blade drive shaft is rotated clockwise by the urging force of the spring 43. It pivots to close the vane via pin 42e.

After that, the motor 9 is rotated in the reverse direction, and the helicoid ring 1c is first retracted and mixed into the annular portion 1b of the lens barrel 1, and then the lens barrel 1 is returned to the most retracted position shown in FIG. In this case, the protrusion 23 of the drive member 23 of the differential device 4
Since a is initially located at the point b on the cam surface 22c of the driven member 22, when the driving member 23 is rotated in the counterclockwise direction, the driven member 22 does not rotate for the first one rotation, and the driving member 22 does not rotate. 23 rotates and moves axially, during which toothed sector arm
The follower 25c of 25 is pushed up to the original position, so that the sector arm is also rotated clockwise around the shaft 25a and returned to the initial position. The stop member supporting / moving member 26 is also returned to the initial position by the pin 25b. In this way, after the members constituting the stop member moving / positioning means 11 are returned to the initial state, the driving member 23 and the driven member 22 are united and reversed, and the lens barrel 1 is moved backward.

Note that the above description describes the shooting operation at a long focal length, but shooting at a short focal length is also possible at the chome register 141.
Input to is different (the moving distance of the shooting lens becomes shorter)
Just do the same operation.

Further, in the embodiment shown above, the stop member moving / positioning means 11, the responding means 10 and the transmitting means 16 and 17 are all constituted by mechanical mechanisms, but these means are constituted by mechanical mechanisms only. Of course, these means may be replaced by non-mechanical devices, for example.

[Correspondence between Invention and Example]

In the above embodiment, the screw shaft 2 and the helicoid ring
1c is the first driving force transmitting means of the present invention, the stop member 12 is also the stopping means, the cam surface 22c is also the second driving force transmitting means, the distance measuring circuit 116 is also the signal outputting means, and the decoder 118 is used. Similarly corresponds to the action amount determining means.

〔The invention's effect〕

As described above, according to the present invention, it is possible to perform lens movement control at high speed and with high accuracy with respect to a signal for focus adjustment.

[Brief description of drawings]

FIG. 1 is a diagram showing a conceptual configuration of an object moving / positioning device according to an embodiment of the present invention, and FIG. 2 is a main part of a camera equipped with a device embodying the conceptual configuration of FIG. FIG. 3 is an exploded perspective view, FIG. 3 is a horizontal sectional view when the lens barrel of the camera shown in FIG. 2 is at the most retracted position, and FIG. 4 is a position where the lens barrel of the camera shown in FIG. FIG. 5 is a horizontal sectional view at a certain time, FIG. 5 is an exploded perspective view of a main part of a shutter driving mechanism of the camera of FIG. 2, and FIG. 6 is a diagram showing a part of a control circuit of the camera of FIG. 1 ... Lens barrel, 2 ... Screw shaft 3 ... Gear, 4 ... Differential gear 6 and 7 ... Gear, 8 ... Power transmission switching mechanism 9 ... Motor, 10 ... Response means 11 ... Stop member moving / positioning means 12 …… Stop member, 15 …… Actuation control means 16 and 17 …… Transmission means 18 …… Control circuit 19 …… Momentum detection means, 20 …… Vane drive lever 22 …… (Differential device 4) Driven member 23 ...... (Differential device 4) Drive member 25 ...... Toothed sector arm 25b ...... Pin, 25c ...... Follower 26 ...... Stop member supporting and moving member 29 ...... Claw member, 31 …… Second lever 32 …… Magnet, 33 …… First lever 34 …… Third lever 36 …… Converter lens holding frame 36 e …… Engagement part, 38 …… Blade opening lever 40 …… Blade release claw, 42 ...... Blade drive shaft 44 ...... Shutter blade

Claims (1)

[Claims] 1. A first driving force transmitting means for transmitting a driving force at a first gear ratio for moving a lens unit, a stopping means for stopping the lens unit, and the stopping means for the lens. Second driving force transmitting means for transmitting a driving force at a second gear ratio different from the first gear ratio for moving the position to stop the unit, and a signal output for outputting a signal for focus adjustment Means, and an action amount determining means for determining an amount to be applied by the first driving force transmitting means and the second driving force transmitting means in accordance with a moving amount of the lens unit with respect to a signal from the signal outputting means. A lens moving device comprising: