JPH03121436A - Vibration insulator for optical system - Google Patents

Abstract

PURPOSE:To attain correct vibration insulation from immediately after actuator operation is started without generating ringing by allowing the timing of starting of an actuator operation to accord with when a shaking vibration speed is zero. CONSTITUTION:A vibration insulator is provided with an actuator operation starting timing means 22 actuating an ultrasonic motor 120 as an actuator driving an optical system in a direction deadening the shaking vibration of the optical system when the shaking vibration speed becomes zero after the input of a signal starting shaking vibration preventing action. Therefore, by allowing the timing of starting of the actuator operation to accord with when the shaking vibration speed is zero, the need of rapid accelation is eliminated and accelation is gradually carried out according to the accelation of the shaking vibration speed. Thus, the correct vibration insulation can be attained from immediately after it is started without generating the ringing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vibration isolating device for an optical system that prevents blurring of an optical system in, for example, a camera.

[Prior Art] Various types of anti-vibration devices for optical systems in cameras, for example, have been proposed. A typical example of these is a method in which the vibration of the optical system is detected by a sensor, an actuator is operated according to the output of the sensor, and this rotates the imaging lens system to cancel out the vibration of the optical system. Anti-vibration devices are known.

[Problems to be Solved by the Invention] The actuator of the vibration isolator must accurately follow the vibration of the optical system. However, there is always a follow-up delay in the actuator. In particular, at the start of operation, the actuator had to be brought up to the current vibration speed from a stopped state, resulting in a large follow-up delay. For example, if you start the actuator when the vibration velocity is at its maximum, the actuator will move to zero velocity (
The speed changes from the state of 0) to the state of maximum speed, and at this time, large ringing occurs. This ringing required a considerable amount of time to converge, and a large time delay occurred before accurate vibration isolation was achieved.

The present invention was made with attention to such problems,
The purpose is to provide an optical vibration isolator that does not cause ringing and can perform accurate vibration isolation immediately after the start of operation.

[Means for Solving the Problems] The vibration isolating device for an optical system of the present invention includes a speed detection means for detecting the speed of shake vibration of the optical system, and a speed detection means based on the speed of the shake vibration detected by the speed detection means. an actuator for driving the optical system in a direction that cancels vibration of the optical system;
and actuator operation start timing means for starting the operation of the actuator when the speed of the shake vibration becomes zero after inputting a signal to start the shake vibration prevention operation.

[Function] By matching the timing of the actuator operation start to the time when the speed of the shaking vibration is zero (0), there is no need for any sudden acceleration, which was previously required, and it is possible to accelerate gradually in accordance with the acceleration of the shaking vibration. good. Therefore, no ringing occurs, and accurate vibration-proofing operation can be performed immediately after the start of operation.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows the internal structure of a camera according to the present invention, and FIG. 2 similarly shows the exterior structure of the camera.

That is, 131 indicates a holding member that is approximately T-shaped and is used to maintain the strength of the camera. This holding member 131 is made of, for example, aluminum die-casting or high-strength plastic molding material, and the rear cover of the camera is attached to the -end. Rising part 1 for attaching the opening/closing lock unit 400 of 115
31d is arranged. This rising portion 131d has a rectangular hole, and when the opening/closing lock unit 400 is attached to the outside, a part of the opening/closing lock unit 400 protrudes inward from the hole, and the rear cover 115 is connected to the protruding mechanism. It is configured to engage with the lock member 115d to form an opening/closing locking mechanism.

The other end of the T-shaped holding member 131 has a rising portion 13.
1e, and a hinge receiver 401, which serves as a fulcrum for opening and closing the rear lid 115, is fixed to the upper surface of the hinge receiver 1e with screws.

Furthermore, the hinge receiver is located below the portion 401, the hinge receiver is paired with the portion 401, and a pair of rotation means 1 of the rear lid 115 is provided.
The other hinge receiver that supports the protrusion 15e has a portion (not shown) fixed thereto.

The T-shaped outer peripheral surface of the holding member 131 has an edge that is higher than the center, and the center has four parts, which serve to increase the rigidity of the whole.

Furthermore, a plurality of mounting holes are provided on the outer periphery of the holding member 131.

As shown in FIG. 1, the holding member 131 has a raised portion 131f on the film surface side near the center of the T-shape and a stepped portion 13'la for housing the acceleration sensor 118. As shown in FIG. 3, the upper end of the rising portion 131f is provided with a smooth hemispherical bearing surface 131b and a mounting hole 131C for fixing the presser plate 129. The holding plate 129 has a cylindrical shape with a hole 129b in the center and a protrusion 1 extending on both sides due to the cylindrical shape.
29d and a mounting hole 129c for attaching to the holding member 131. Further, a smooth hemispherical bearing surface 129a is formed on the lower surface of the center of the presser plate 129.

In FIG. 3, 130 is a spherical support shaft with a threaded portion 130a formed at one end. This support shaft 130 is held between a holding member 131 and a presser plate 129 by a screw,
It won't come off.

In addition, the spherical shape of the support shaft 130, the spherical shape of the bearing surface 131b of the holding member 131, and the spherical shape of the bearing surface 129a of the presser plate 129 match with an extremely small gap, so there is no play and smooth rotation. It is held in such a way that it can be Note that the threaded portion 130a of the support shaft 130 is engaged with and fixed to the first structural member 101.

In FIG. 2, reference numeral 134 denotes a tunnel-shaped lens barrel exterior member with a partially rounded surface, a raised portion at the film side end, and a mounting hole for fixing to the first holding arm 402. It is set up. Further, mounting holes for fixing to the holding member 131 are provided at both ends of the bottom surface side of the lens barrel exterior member 134. This lens barrel exterior member 134 is connected to the holding member 131 and the first holding arm 402 through the mounting hole.
When the lens barrel exterior member 134 and the lens barrel 100 of the camera are fixed to each other, a certain gap is maintained between the lens barrel exterior member 134 and the lens barrel 100 of the camera.

The first holding arm 402 is a plate-shaped part with a curved surface part having a substantially arc shape in the center and flat parts on both sides, and has mounting holes at both ends for fixing to the holding member 131 and an exterior member. There are mounting holes for mounting. By being integrally fixed to the holding member 131, the first holding arm 402 plays the role of a strength member for supporting the exterior member so that it will not be deformed when external force is applied.

The second holding arm 403 is a plate-shaped component having two bends at both ends and a mounting hole for fixing it to the holding member 131. Like the first holding arm 402, the second holding arm 403 is fixed to the holding member 131 with screws or the like, and is used to support the exterior member to prevent deformation when an external force is applied. It plays the role of a strength member.

A right side exterior member 404 is fixed to the first holding arm 402 and the holding member 131 with screws, and is fixed to the camera body mechanism block 405 and the lens frame 100 with a constant gap. Here, the camera body mechanism block 40
5 refers to the second structural member 102 that connects the operating mechanism of the camera, such as the camera winding mechanism, mirror mechanism, and finder mechanism.
A mechanical unit attached to the third structural member 103 is shown. 406 is a left side exterior member, and the first holding arm 4
02 and the holding member 131 with screws to prevent deformation like the right side exterior member 404, and is also fixed to the camera body mechanism block 405 and the lens frame 100 with a certain gap maintained.

135 is the upper cover of the camera, and this upper cover 135 is
First holding arm 402 and second holding arm 403
, are fixed to the rising portions 131d and 131e of the holding member 131. At this time, like other exterior members, it is fixed to the camera body mechanism block 405 with a constant gap maintained.

Reference numeral 136 denotes an eyepiece frame cover, and this eyepiece frame cover 136 is integrally fixed to the rear end surface of the upper cover 135, and is fixed to the eyepiece frame 112 of the camera body mechanism block 405 with a certain gap maintained therebetween.

On the other hand, the rear lid 115 is provided with steps 115a, 115b, and 115c surrounding the periphery to prevent light leakage, and at one end is provided with a pair of rotating shafts for opening/closing hinges provided by a known method. 115e and a lock member 115d for opening/closing lock. The rear cover 115 is formed by molding a high-strength plastic mold material.
Since this is a part where external force is easily applied during operation, reinforcing ribs 115f are formed on the inside.

Further, a film pressure bonding plate 114 is attached to the rear lid 115 and is elastically held by a leaf spring 137 for keeping the film in a predetermined position.

The film pressure bonding plate 114 is pressed against the upper and lower pressure bonding plate rail surfaces 103 of the third structural member 103 by the pressure force of the leaf spring 137.
It is crimped to a.

The first bottom plate 116, which has a raised portion around its periphery and has a notch in a portion thereof, is fixed to the holding member 131 so as to cover the bottom surface of the holding member 131 on the film side. Further, the second bottom plate 138 is fixed to the holding member 131 so as to cover the bottom surface of the holding member 131 on the lens side. Further, the third bottom plate 139 is located below the tip of the lens of the camera, and is fixed to the holding member 131, and is fixed to the tip of the lens barrel 100 with a certain gap maintained therebetween.

Next, the internal structure of the camera will be described mainly with reference to FIG. In FIG. 1, reference numeral 100 indicates a so-called lens barrel portion that is equipped with an autofocus mechanism, an electric zoom mechanism, an aperture mechanism, a cross focus (close-up photography), etc. (not shown) of the camera by an interlocking mechanism (not shown). Further, 100a to 100r are built into the lens frame 100,
This figure shows a photographic lens that is configured to perform predetermined photographing through operations such as autofocus, zoom, and macro photography, depending on their respective positional relationships. The lens frame 100 has an arc-shaped protrusion 101 around its periphery! Cm2) is provided, and the camera body mechanism block 405
It is fixed to the second structural member 102 with screws or the like to maintain its strength.

The strength members of the camera body mechanism block 405 are
In addition to the second structural member 102, it is composed of a first structural member 101 and a third structural member 103, which are assembled with screws or the like so that they are integrally fixed to each other. In addition to the first structural member 101 and the second structural member 102, the first structural member 101 and the third structural member 103 are constructed, and are assembled with screws or the like so that they are integrally fixed to each other. .

Furthermore, a first structural member 101 and a second structural member 102
The third structural member 103 is molded from aluminum die-casting, high-strength plastic, or the like, and maintains sufficient strength.

On both sides of the film of the photographing lens 100r, there is a movable mirror 104 of a single-lens reflex camera, and a movable mirror frame 105 that supports the movable mirror 104 and has a rotation center point 105a at one end.
Further, a splitting mirror 106 is provided on the movable mirror frame 105 to split the optical path from the photographing lens and guide the optical path to the autofocus sensor 108 .

The split mirror 106 is held by a split mirror frame 107 that supports the split mirror 106 and moves it out of the optical path during photographing. These movable mirror mechanisms and autofocus mirror mechanisms are configured to retreat from the photographing optical path in conjunction with the release of the camera using a known method.

The light passing through the photographic lens is reflected by a movable mirror 104 and forms an image on a finder screen 109.

Then, the photographer views the finder screen 10 through the pentaprism 111 and the eyepieces 112a and 112b.
The photographed image formed at 9 can be seen. Also,
A finder screen 109 and a pentaprism 111 are held by a prism frame 110. Prism frame 1
10 is a second structural member 1 made by a method known in the art for single-lens reflex cameras.
It is held at 02. Eyepiece lenses 112a, 112b
is fixed to the eyepiece frame 112, and this eyepiece frame 1
12 is integrally fixed to the second structural member 102.

Movable mi? A focal brain shutter 113 is disposed on the film surface side of -104, and is disposed so that opening and closing of the shutter 113 can be controlled based on a drive circuit (not shown), and is configured to perform exposure using a known method. ing.

The lens frame 100 is fixed to a first structural member 101. The first structural member 101 is a plate-like member having a substantially T-shape (see Fig. 2), and a mounting hole is provided in a part of the first structural member 101 to securely attach the second structural member 102 and the third structural member 103. It is formed to do so.

Below the first structural member 101, roller bearings 126 for holding a roller 125 and a roller shaft 132 as shown in FIG. 4 are fixed at both left and right ends. Roller bearing 1
26 has mounting holes provided at both ends, and a screw for engaging the roller shaft 132 in the center. The roller shaft 132 has a thread formed at one end, and a portion of the roller shaft 132 has a screw thread formed at one end.
This is a stepped screw with a stepped portion that fits into the screw. This roller shaft 132 holds the roller 125 in a roller bearing 126 so as to be able to rotate smoothly without play.

In addition, near the front end of the first structural member 101 on the lens side,
Spring catch 133 for fixing the hook part of the spring 123
has been planted. Furthermore, a guide shaft 128 for unidirectional control is implanted toward the bottom near the center of the first structural member 101 .

Further, a support shaft 130 is fixed substantially below the film surface of the first structural member 101 without any wobbling, and the first structural member 101 and the second structural member 102 are connected around the support shaft 130. , the third structural member 103, the lens frame 100 and the camera body mechanism block 4 fixed thereto.
05 can be rotated smoothly in the pitching direction and in the yaw direction without any play.

A first acceleration sensor 117 for detecting camera shake at the tip of the lens is fixed on a plane forming a concave portion on the upper surface of the holding member 131. On the film surface side of the acceleration sensor 117, below the optical axis is a first ultrasonic motor 1.
20 is fixed, and a three-dimensional cam 124 is fixed to its output shaft. As shown in FIG. 5(a), the three-dimensional cam 124 has a bearing portion 124a disposed in the center thereof to be integrally fixed to the output shaft of the first ultrasonic motor 120, and extends in a direction perpendicular to the output shaft. It is clamped with a screw to allow rotation in one direction.

Optical signals and magnetic signals for rotation control are recorded on the outer periphery of the three-dimensional cam 124, and photoreflectors (limit sensors) 139a and 13 are used to read the optical signals.
9b and a magnetic sensor 140 for reading magnetic signals are arranged at a certain distance from the outer periphery.

These photoreflectors 139a, 139b and the magnetic sensor 140 are fixed to a mounting base 142 for finely adjusting the height relationship and gap with the outer periphery of the three-dimensional cam 124. Note that the other end of this mounting base 142 is attached to the holding member 13.
It is fixed at 1.

Incidentally, on the upper surface side of the three-dimensional cam 124, two cam surfaces 124b are arranged, which change from the maximum lift to the minimum lift with rotation of the first ultrasonic motor 120 through about 180 degrees. A roller 125 comes into contact with this cam surface 124b,
The rotational movement of the first ultrasonic motor 120 makes it possible to move the first structural member 101 up and down via the rollers 125.

As shown in FIG. 5(b), the roller 125 is rotated in one direction around the support shaft 130 by a second ultrasonic motor 121, which will be described later, so it rotates slightly on an arc of radius R. move. At this time, in order to prevent as much as possible the contact point between the roller 125 and the cam surface 124b from shifting and rotation in the pitch direction, the roller 125 is moved against the cam surface 124b as shown in FIG. 5(b). The three-dimensional cam 124 has a cam surface 124b that is slightly bent along an arc with a radius R, and the cam surface 124b of the three-dimensional cam 124 is such that the contact surfaces of the two rollers 125 each have the same cam lift amount. A shape is formed.

The cam surface 124b is driven by a first ultrasonic motor 12 whose drive is controlled in relation to a camera shake signal from an acceleration sensor, which will be described later.
The first structural member 101 is moved up and down according to the direction and amount of rotation of 0, and is configured to be able to correct camera shake vibrations of the lens frame 100 and camera body mechanism block 405 fixed to the first structural member 101. There is.

Near the lens-side tip of the holding member 131, below the spring hook 133 implanted in the first structural member 101, there is another
Two spring hooks 122 are installed, and between the spring hooks 133 and 122, a roller 125 and a three-dimensional cam 124 are installed.
A tension spring 123 is provided to keep the two in contact with each other at all times. The spring 123 moves the camera up and down using the three-dimensional cam 124.
Even when the three-dimensional cam 124 and the roller 125 move back and forth at high speed, they are held together with a sufficiently strong tension so that they do not separate.

A second ultrasonic motor 121 is fixed to the holding member 131. The output shaft of the second ultrasonic motor 121 has
A cam 127 as shown in FIG. 6 is fixed. A cylindrical protrusion for fixing the output shaft of the second ultrasonic motor 121 is formed below the center of the cam 127, and a fitting hole 127b that engages with the output shaft and the output shaft and the cam 127 are formed. Hole 127 for attaching a clamp screw to integrally fix the
C is arranged and fixed together with a clamp screw. Further, the cam 127 is machined with a groove 127a having a constant width whose distance from the center of the cam changes as it rotates.

On the other hand, the first structural member 101 has a cam 1 as described above.
A guide shaft 128 is fixedly provided so as to fit into the groove 127a of No. 27. As shown in FIG. 7, the guide shaft 128 is formed of an arc-shaped shaft that is equidistant from the center of the support shaft 130, and has a slight gap so that it can slide smoothly on the cam groove 127a without any play. They are mated together.

Then, due to the rotation of the three-dimensional cam 124, the first structural member 1
01 swings up and down, the guide shaft 128 moves into the cam groove 1.
Since the distance Mr from the support shaft 130 does not change even if the 27a is rocked up and down, there is no risk of malfunction between the cam groove 1278 and the cam groove 1278.

Further, it has a sufficient length so that the guide shaft 128 does not come off from the cam groove 127a.

Here, in order to further increase the reliability of operation, the guide shaft 128 on an arc has been described, but if the distance r between the support shaft 130 and the guide shaft 128 can be maintained at a certain value or more, the swing range can be increased. When using a camera shake prevention mechanism of about 1 to 2 degrees, even if the guide shaft 128 is straight, a slight gap between the cam groove 127a and the cam shaft 127a can prevent malfunctions caused by the rocking. be.

When the second ultrasonic motor 121 rotates, the guide shaft 12
8 is guided by the cam shaft 127a of the cam 127, and the distance from the output shaft of the second ultrasonic motor 121 changes. At this time, the first structural member 101 rotates in one direction around the support shaft 130. On the other hand, the guide shaft 128 and the cam shaft 12
7a has enough strength and sliding properties to support the weight of the camera and allow it to slide smoothly without wobbling even when the camera is held in the vertical or horizontal position.

In the holding member 131, a control unit 119 consisting of an acceleration signal processing circuit, an ultrasonic motor drive/control circuit, etc. is arranged substantially below the second structural member 102. Control part 1
Reference numeral 19 designates the entire signal processing circuit and drive control circuit for correcting camera shake according to the present invention, which will be described later, and includes a vertical control circuit and a horizontal control circuit, respectively. Further, a notch 131a is formed at the end of the holding member 131 on the film surface side, and a second acceleration sensor 118 is disposed in the notch 131a.

Next, the configuration of each part of the control section 119 will be explained using the overall block diagram of FIG. 8. However, only a device for eliminating camera shake vibration in the vertical direction will be described here, but the horizontal direction can be handled using a circuit similar to that in the vertical direction. Reference numerals 117 and 118 are acceleration sensors for detecting camera shake vibrations, which are arranged at the front and rear parts of the camera in FIG. The sensitivity directions of these acceleration sensors 117 and 118 are arranged in the vertical direction, and when upward acceleration is applied, a positive voltage is applied, and when downward acceleration is applied, a negative voltage is applied. arranged for output.

3 is a subtraction circuit that outputs the difference between the outputs of the acceleration sensors 117 and 118. That is, if the output of the acceleration sensor 117 is Van, the output of the acceleration sensor 118 is Va2, and the output of the subtraction circuit 3 is Va, then Va-Val-Va2 is obtained. This is a signal indicating the acceleration of the vertical rotational movement of the camera. For example, assume that acceleration sensor 117 receives upward acceleration and acceleration sensor 118 receives downward acceleration. At this time, Val >0. Va2 <0
Therefore, Va>Q. This means that the vertical rotational movement of the camera has been accelerated upward.

The acceleration signal Va is input to the integrating circuit 5, and the velocity signal vv
is converted to An example of input and output waveforms of the integrating circuit 5 is shown in FIG. In this example, since the human power Va is a sine wave, the output is also a sine wave with a 906 phase delay.

7 is a comparator that compares the speed signal v and a signal vR indicating the rotational speed of an ultrasonic motor (hereinafter simply referred to as USM) 120, which will be described later, and outputs the result as a digital signal So (count direction signal). Output. That is, when rotational speed signal VR>speed signal VV, SD-
H" (high level), when vR<vv, SD-"
Outputs “L” (low level).

9 is an absolute value circuit which inputs the acceleration signal Va and outputs its absolute value 1Val. An example of input/output waveforms is shown in FIG.

10 is a voltage controlled oscillator (hereinafter simply abbreviated as VCO)
Then, input the absolute value IVal of the acceleration signal Va, and set it to 1Va.
Outputs a pulse with a frequency proportional to the voltage of l. That is, when IVal is small, a low frequency pulse is output, and when 1Val is large, a high frequency pulse is output.

11 is a 4-bit up/down counter, which has an up/down count switching terminal U/ as an input terminal.
D, clock input terminal CK, preset value input terminal D3
~DO, and count value output terminal Q3 as an output terminal
~Have QO. When the signal input to the up-count/down-count switching terminal U/D is "Lo", up-counting is selected, and when it is "Ho", down-counting is selected. This input terminal U/D is connected to the output of the comparator 7 via an overflow prevention circuit 12, which will be described later. The clock input terminal CK is connected to the output of VCOIO,
Counting is performed by the rising edge of the input pulse.

When the signal input to the preset terminal PR is 'H', a normal counting operation is performed, and when it is 'Lo', a preset operation is performed. The preset operation is an operation in which the value (binary number) input to the preset value input terminals D3 to DO is set as a count value, regardless of the clock input to the clock input terminal CK. Here, D3 represents the most significant digit of the preset value, and DO represents the least significant digit. For example, if “H”-1, “L”-〇, the preset value (D3.D2.DI.

Do) is (H, L, L, L) -(1,0,O,O
), when a preset operation is performed, the count value (Q3.Q2.Ql.

QO) is set to (1,0,0,O). here,
Q3 represents the most significant digit of the count value, and QO represents the least significant digit.

The preset terminal PR is connected to an output terminal of an anti-vibration on/off control circuit 22, which will be described later, and this signal is also input to a sequence control circuit 23, which will also be described later. Preset value terminals D3 to DO are connected to output terminals of the sequence control circuit 23. Count value output Q3 to QO are terminals that output the count value (Q3.Q2.Ql, QO) set in the counter 11.
An overflow prevention circuit 12, a D/A converter (hereinafter simply referred to as DAC) 13, and a USM on/off circuit (described later)
It is connected to the off circuit 14.

The overflow prevention circuit 12 is a circuit for preventing the counter 11 from overflowing, and a detailed circuit diagram thereof is shown in FIG. This circuit is based on the count value (Q
3. Q2. When Ql, QO) becomes (0, O, O, O,) or (1, 1, 1°1), the input of the terminal U/D is connected to the output Q3 of the counter 11 itself by the AND/OR circuit 201. This is a circuit that switches to (Q
3. Q2. Ql, QO) is (0, O, 0゜0,)
Or when the value is other than (1, 1, 1, 1), the terminal U/
A normal count direction signal S D s, that is, the output of the comparator 7 is input to D. Count value (Q3.Q
2. Ql, QO) is (0,0°0.0.), the terminal U/D is connected to Q3-0 by the AND/OR circuit 201.
-“Lo is input, and the mode of the counter 11 is fixed to the up-counting mode. Also, (Q3.Q2.Q
l.

QO)-(1, 1, 1, 1,), Q3-1-"H" is input to the terminal U/D, and the mode of the counter 11 is fixed to the down-counting mode. That is, this overflow prevention circuit 12 prevents the counter 11 from overflowing, that is, the count value (Q3
．． Q2. Ql.

QO) changes such as (0, 0, 0, 0,) → (1, 1, 1 ° 1) or (1, 1, 1, 1,) groan (0, 0, 0 ° 0) is prevented.

13 is a DAC (D/A converter) whose input is a count value output terminal of the counter 11, and whose outputs are connected to a control terminal of a USM control circuit 15, which will be described later. This DAC 13 receives the input digital value (Q3.
Q2. Analog voltage V CON proportional to Ql, QO)
Outputs d (control voltage). FIG. 12 shows the input/output characteristics of the DAC 13. In other words, the count value (Q3.Q2.Ql,QO) of the counter 11 is (0,0
, 0° 0, ), the output V C0NT of the DAC13 becomes OV, outputs a positive voltage when it is above (1, 0, 0, 1), and outputs a negative voltage when it is below (0, 1, 1, 1). Outputs the voltage of

14 is a USM on/off circuit for sending a USM on/off signal Sυ0 to a USM control circuit 15, which will be described later.The input is to the count value output terminals Q3 to QO of the counter 11, and the output is to the USM control circuit of the USM control circuit 15. connected to the terminal. FIG. 13 shows a detailed circuit diagram of the USM on/off circuit 14. Count value of counter 11 (Q3.Q2
Only when ゜Ql, QO) is (1, O, 0, 0,), the output of the USM on/off circuit 14, that is, the USM on/off signal SUO, becomes ``L''; otherwise, it becomes ``L''. It becomes Ho. The USM control circuit 15, which will be described later, is a USM
When the on/off signal is g L 11, 08M120, which will be described later, is stopped, and when it is 'H' it is activated, so the count value of the counter 11 (Q3.Q2.Ql
, QO) is (1,0,O,O,), the 08M120 will stop, and otherwise operate.

Reference numeral 15 denotes a USM control circuit, which is a circuit for controlling the USM (ultrasonic motor) 120, which is the actuator of this vibration isolation mechanism. Control terminal and 08M as input terminal
It has two on/off terminals and a two-phase U as an output terminal.
From the control terminal that has the SM drive terminal, the DAC
Input the control voltage V CON↑ outputted by 13, and from the 08M on/off terminal, the USM on/off circuit 1
The USM on/off signal SUO output by No. 4 is input.

The output is connected to 08M120.

FIG. 14 shows a detailed block diagram of the USM control circuit 15. The USM control circuit 15 includes an absolute value circuit 203, a logarithmic conversion circuit 204, a VCO 205, a comparator 206, and a USM control circuit 15.
It is composed of an M drive circuit 207. Control voltage V, input from the control terminal. N7 is input to absolute value circuit 203 and comparator 206.

The output IVCONT+ of the absolute value circuit 203 is input to a logarithmic conversion circuit 204 and is converted into a logarithm. The reason why the logarithmic conversion circuit 204 is inserted into the USM control circuit 15 will be described later.

The VCO 205 inputs the output of the logarithmic conversion circuit 204,
A pulse (rotation speed control signal vN) with a frequency fN proportional to this input voltage is output.

The relationship between IVcostl and fN is shown in FIG. 15(b). Regions where the value of IVCONT+ is small, for example VCON
At TI-V2, the slope of the curve is large and IVcON
The rate of change in fN with respect to the change in T+ is large. On the contrary, IV
A region where the value of CONT+ is large, for example, I VcoNt
When l-Vl, the slope of the curve is small and IVcost
The rate of change in fN with respect to the change in l is small. VCO205
The output, that is, the rotational speed control signal vN, is input to the USM drive circuit 207. On the other hand, the comparator 206 determines the sign of the control voltage V C0NT and
A rotation direction control signal SD is output to the M drive circuit 207.

In other words, VCON? When >0, it becomes SD-“L”. Furthermore, the USM output from the USM on/off circuit 14
The on/off signal SUO is also input to the USM drive circuit 207.

The USM drive circuit 207 receives the above three signals, namely, the rotational speed control signal vN1, the rotational direction control signal SD, and the USM drive circuit 207.
It inputs the M on/off signal SUO and outputs the two-phase USM drive signals V UA and V UB. The rotational speed control signal vN is power-amplified and converted into a two-phase USM with a 90″ phase shift.
It is output as drive signals v UA and v us. At this time, vuA, vL, and B have the same frequency as the frequency f of vN. The rotation speed of the 08M120 is controlled by this frequency, that is, the driving frequency fN. vUA and V
The phase relationship (lead/lag relationship) of LIB is determined by the rotation direction control signal SD, and as a result, the rotation direction of 08M120 is determined. This situation is shown in FIG.

That is, when SD-“H”+7), V UA Ka V L
The phase is 9011 ahead of lll, and at this time 08
M120 rotates in the CW force direction (clockwise direction). On the contrary, S
When D- is "L", VUB is in phase 90@ ahead of vuA, and at this time, 08M120 rotates in the CCW direction (counterclockwise). Additionally, the USM on/off signal SU
O turns on and off the USM drive circuit 207. That is, 5u0-“H.

In this case, the USM drive circuit 207 operates as described above and outputs the USM drive signal Vu^+vUB, but
5UO - When “L”, USM drive signal vLIA#
Does not output V LIB. Therefore, as a result, 08
M120 operates when Suo-H and SUom
When it is 'L', it will stop.

120 is a rotation-switchable USM (ultrasonic motor).
Used as an actuator for anti-vibration operation. Although a traveling wave USM is used in this embodiment, other types of ultrasonic motors can be used as long as the rotation direction can be switched. The rotation speed, rotation direction, or on/off of the 08M120 is controlled by the USM control circuit 15. There are various methods of speed control. For example, there are methods of changing the drive voltage, methods of changing the phases of two-phase drive signals, and the like. In this embodiment, a method of changing the drive frequency fN is used.

FIG. 17 shows the relationship between the drive frequency fN and rotational speed N (at no load) of 08M120.

That is, if the USMI 20 is driven at a driving frequency f1 close to f, with its resonant frequency 10 or higher, it will rotate at a high rotational speed Nl, but if it is driven at fl, which is far from f, the rotational speed will be N2. Like slow down. In addition, if the drive frequency fN is set below the resonance frequency f, 08M120
will stop, so fN must be set to a value greater than fo.

That is, speed control is performed in a region where the drive frequency is from fl to fl. Furthermore, as a characteristic phenomenon of this speed control method, that is, a method of controlling the rotational speed N by changing the driving frequency f, there is a phenomenon that fN
There are cases where the rate of change in N changes with respect to a change in .

That is, when the driving frequency fN is small like fl (
At the resonance frequency (close to 0), the rate of change in the rotational speed N with respect to the change in fN is large. On the other hand, if fN is as large as fl (far from fo), then fN
The rate of change in N with respect to the change in is small. This phenomenon is
This is not so much of a problem when M is rotated at a constant speed, but it becomes a problem when the rotation speed is changed from time to time, such as in a vibration-proof operation. This matter will be discussed in the explanation of the operation.

17 is a rotary encoder connected to the rotating shaft of USMI 20, and as 08M120 rotates, 90
@ Outputs two-phase pulse S RAISRB with different phases. In this embodiment, a magnetic encoder with an output of 1000 pulses per rotation is used. The arrangement of the rotary encoder 17 is shown in FIG. 18(b). The rotary encoder 17 includes a magnetic drum 208, a magnetic sensor 209,
It is composed of a waveform shaping circuit 210. magnetic drum 2
08 and the reflecting plate 211 of the photoreflector to be described later,
It is attached to the lower part of the three-dimensional cam 124 and rotates together with it. The side surface of the magnetic drum 208 is alternately magnetized with N and S poles. The magnetic sensor 209 is fixed at a position facing the magnetized surface of the magnetic drum 208, detects changes in the magnetic field due to rotation of the magnetic drum 208, and outputs two-phase signals with a 90° phase difference. The waveform shaping circuit 210 inputs this signal, shapes the waveform, and outputs a digital signal S RA * S RB.

The rotary encoder 17 outputs high frequency pulses when the rotation speed of the 08M120 is fast, and lowers the frequency when the rotation speed is slow. Furthermore, the phase relationship (advanced/delayed relationship) between the two-phase pulses changes depending on the rotation direction. That is,
When the 08M120 is rotating in the CW direction (clockwise direction), the phase of the two-phase pulse is SRA leading with respect to SRB, but when rotating in the CCW direction (counterclockwise), S, lB is progressing against SRA. This situation is shown in FIG.

18 is a rotation speed detection circuit, and a rotary encoder 17
Input the two-phase pulse SRA+SRB output by
An analog signal VR (rotation speed signal) indicating the rotation speed of the USMI 20 is output. That is, the frequency of SRAhsRB is measured, converted to an analog voltage, and output (the absolute value of the output vR is proportional to the frequency of SR^+SRB). Also, from the phase relationship of SRA+SRB, U
The direction of rotation of the SMI 20 is determined and the sign of the output vR is determined. That is, if the 08M120 rotates in the CW force direction, the phase of the output of the rotary encoder 17 will be SRA.
advances, at this time the output v of the rotational speed detection circuit 18
FL becomes a positive value. Conversely, if the USMI 20 rotates in the CCW direction, the output of the rotary encoder 17 will be S.
RB becomes advanced and the output vR becomes negative. As described above, the rotation speed signal vR, which is the output of the rotation speed detection circuit 18, is sent to the comparator 7.

Reference numerals 139a and 139b are limit sensors, which are used to detect the limit angle of rotation of the three-dimensional cam 124 in the cw and ccw directions, as shown in FIG. 18, and detect that the three-dimensional cam 124 has reached the limit angle. If so, USMI6 will be stopped.

In this embodiment, photoreflectors are used as the limit sensors 139a and 139b. The limit sensor 139a is C
The limit sensor 139b detects the limit of rotation in the W direction and the limit of rotation in the CCW direction.

FIG. 18 shows the arrangement of limit sensors 139a and 139b. A reflecting plate 211 of a photoreflector is attached to the lower part of the three-dimensional cam 124 together with the magnetic drum 208, and rotates together with the three-dimensional cam 124. Reflector 2
Area A (180' in terms of angle) of No. 11 is a surface with good reflectivity for infrared light, and area B is a surface with poor reflectance.

The limit sensors 139a and 139b emit infrared light and detect the reflected light, thereby outputting "L" when facing the A area of the reflecting plate 211, and outputting "L" when facing the B area. Outputs “H”.

Here, the limit of the operation of the three-dimensional cam 124 means that the roller 12
5 reaches the step C of the three-dimensional cam 124. Further, the step C is a portion where a step is formed at the end of the two cams of the three-dimensional cam 124.

That is, if the three-dimensional cam 124 is rotated until the roller 125 crosses the step C, the proportional relationship between the rotation angle of the three-dimensional cam 124 and the lift amount of the roller 125 will collapse. Or, the roller 125 is in contact with the step C and the cam 124
may stop rotating. Therefore, roller 12
5, the USMI 20 is forcibly stopped before it reaches the step C. If the limit sensors 139a and 139b are placed at the positions shown in FIG. 18(a), the limit sensors 139
The output of either one of a and 139b becomes "H". Note that D and E indicate the boundary points of the reflectors of the limit sensors 139a and 139b.

That is, when the three-dimensional cam 124 continues to rotate in the CW force direction, the output of the limit sensor 139a becomes "L" when the point D of the reflection plate 211 comes to a position facing the limit sensor 139a.
'' to 'H#. When rotating in the CCW direction, the output of the limit sensor 139b changes from "L" to "H" when the point E of the reflector 211 comes to the position facing the limit sensor 139b. The limit sensor 139a changes.

When the output of either one of 139b becomes "H", if the USMI 20 is forcibly stopped, the roller 1
25 will never go over step C. Note that the angle θL
may be determined to be an appropriate value based on the size of the roller 125, the stopping accuracy of the USMI 20, etc.

21 is a limit detection circuit, which is a limit sensor 139a.

Each output SLA+SLB of 139b and the speed signal vv are input, and a limit stop signal SL is output. The limit stop signal SL is input to an anti-vibration on/off control circuit 22, which will be described later. A detailed circuit diagram of the limit detection circuit 21 is shown in FIG. That is, S becomes -1 only when 5LA-"Ho and vv>0.

22 is an anti-vibration on/off control circuit which inputs the speed signal vv, the limit stop signal SL, and the anti-vibration on/off signal SBo output from a sequence control circuit 23, which will be described later, and outputs a preset signal SPR.

The preset signal SPR is input to the preset terminal PR of the counter 11 and the sequence control 1 circuit 23. A detailed circuit diagram of the anti-vibration on/off control circuit 22 is shown in FIG. The anti-vibration on/off control circuit 22 includes a D-type flip-flop circuit 215, a comparator 213, and a NOR gate 21.
4. The anti-vibration on/off signal SBO is input to the input of the flip-flop circuit 215.

Further, the speed signal vv is input to a non-inverting input terminal of the comparator 213. The output of the comparator 213 is connected to the clock input CK of the flip-flop circuit 215, and changes from "L" to "Ho" when the value of the speed signal vv changes from negative to positive. The state of the input appears at the output Q.

Preset signal SPR which is the output of NOR gate 214
becomes "L2" when at least one of the output Q1 of the flip-flop circuit 215 or the limit stop signal SL is 'L2.

23 is a sequence control circuit that controls the sequence of the entire vibration-proofing operation. In this embodiment, a microcomputer is used. As inputs, there are the output 5LBs of the limit sensor 139b, the output SR^ of the rotary encoder 17, the output of the anti-vibration on/off control circuit 22, that is, the preset signal 5PRs, the anti-vibration on signal and the anti-vibration off signal output by means not shown. Anti-vibration on/off signal SB as output
O and preset values D3 to DO input to the counter 11
There is. The anti-vibration on signal is outputted, for example, by turning on the first Lurie switch of the camera, and the anti-vibration off signal is outputted, for example, by a shirt closure completion switch.

The preset value (D3.D2.DI, DO) is usually (,1
,0,O,O). When the anti-vibration on signal is input, the anti-vibration on/off signal SBO is changed from "Ll" to "Hl" in order to start the anti-vibration operation. Furthermore, when the vibration isolation off signal is input, the vibration isolation on/off signal SBO is changed from "H" to "L" in order to stop the vibration isolation operation. Stopping of the anti-vibration operation can be confirmed by the preset signal SPR.

When it is confirmed that the anti-vibration operation has stopped, that is, when the preset signal SPR changes from 'H' to 'Ll', an initializing operation is performed next. First, preset value (D3.
D2. Dl, Do) are set to values below (1, 0, 0, 0), for example (0, 1, 1, 1).

By doing this, the three-dimensional cam 124 can be moved CCW.
It can be rotated in any direction. If the rotation continues in the CCW direction, E in FIG. 18(a) is the limit sensor 139.
reaches the position opposite to a, and the output S of the limit sensor 139a
LB changes from "L" to 'H#. The sequence control circuit 23 detects this and sets the preset value (D3.D2.D
I, Do) to a value greater than or equal to (1,0,0,0), for example (
1°0.0.1). Then, the three-dimensional cam 124 rotates in the CW force direction. At this time, the rotary encoder 17 outputs pulses, and the sequence control circuit 23 counts them, and when the roller 125 reaches the middle position of the slope of the three-dimensional cam 124,
When the cam 124 reaches the position shown in FIG. 18(a),
stop the rotation. That is, E is the limit sensor 139
From the position facing b, the angle is 01 from θL,
The cam 124 is rotated in the CW force direction. Since the number of output pulses of the rotary encoder 17 is proportional to the rotation angle, the rotation angle can be detected by counting the number of pulses.

Also, when finally stopping the cam 124, the preset value (D3.D2°DI, DO) is set to (1,0,O,O
).

Next, an explanation will be given of the operation of the camera incorporating the camera shake isolating device configured as described above.

First, in FIG. 1, the state before the vibration damping operation is started will be explained. As mentioned above, the first structural member 101 is attached with the lens barrel 100, which is the main mechanical part of the camera, as well as the finder mechanism, the mirror mechanism, and the winding mechanism attached to the third structural member 103. , is freely rotatable up and down and left and right around the support shaft 130. Furthermore, the lens barrel 100 and camera body mechanism block 405 attached to the first structural member 101 are
Exterior parts 134, 135, 116, 139°138.4
04, 406, and 136, and are held at a constant gap (as described above).

Before the anti-vibration operation is started, the three-dimensional cam 124 is in the first position.
The roller 125 is stopped at the initial position shown in FIG.

This is the position where the above-mentioned initialization operation is completed and stopped.

Suppose now that a photographer is holding the camera and vibration is being applied to the camera in the vertical direction.

Further, it is assumed that the vibration vibration is a simple harmonic motion. When the anti-vibration circuit is activated in conjunction with the camera's operation switch or release button, the acceleration sensors 117 and 118 detect the vertical acceleration applied to the front and rear parts of the camera, respectively, and generate a signal. Output Va1 and Va2. Then, the subtraction circuit 3 outputs the difference VamVa1-Va2. This value Va represents the acceleration of the vertical rotational movement of the camera. The acceleration signal Va is an integral concave path 5
is converted into a speed signal vv by

Next, when an anti-vibration on signal is input to the sequence control circuit 23, the anti-vibration on signal is input to the sequence control circuit 23, which is connected to the release switch of the camera, for example, the second stage release switch or the mirror drive switch. is the anti-vibration on/off signal S to start the anti-vibration operation. Change B from “L” to “Hl”.

Upon receiving this, the anti-vibration on/off control circuit 22 switches the preset signal SPR from II L II to "H" at the moment the speed signal vv changes from negative to positive, that is, when it becomes vv-0. The counter 11 does not perform a counting operation while the preset signal SPR input to the preset terminal PR is "L", and the sequence control circuit 23
Preset values output by (DB, D2.Dl, Do) -
(1,0,0°0,) is output as is. While the output (Q3, Q2.Ql, QO) of the counter 11 is (1,0°0.0.), the USM on/off signal SUO from the USMS geometries circuit 14 is “L”, and as a result, The USM control circuit 15 receives the USM drive signal Vυ^#”D
Does not output B. In other words, 08M120 is stopped.

When the preset signal SPR becomes “H”, the counter 11
starts counting operation. When the counter 11 performs up-counting or down-counting and the count value deviates from the median value (1, 0, 0, O,), the USMS geomuff circuit 14 detects this, and the USM on/off signal S
The USM control circuit 15 receives the USM on/off signal SUO and starts outputting the drive signal vuA+V LIB to the 08M120.
120 rotates. The reason why the motor starts operating at the moment when the speed signal vv-0 is "0" is because when the speed signal vv is "0", this is the moment when the vibration has stopped, so the motor's follow-up delay can be minimized. It is.

Further, the count value of the counter 11 is converted into a control voltage V CONT by the DAC 13 and sent to the USM control circuit 15 . Since the USM control circuit 15 outputs drive signals V gA and V us having a frequency fN according to the control voltage V C0NT, the rotation speed of the 08M120 changes according to V C0NT. Note that even if the count value of the counter 11 changes greatly and becomes saturated, the overflow prevention circuit 12 prevents the count value from changing from the maximum value to the minimum value or vice versa. 20 will not suddenly rotate backwards.

The USM control circuit 15 of this embodiment controls the rotation speed of the 08M120 by changing the drive frequency fN. However, as described above, the relationship between the drive frequency fN and the rotational speed N is not linear but exponential (see FIG. 14). Shake vibrations are thought to be caused by constant changes in speed and acceleration, so
To correct this, the speed and acceleration of the USMI 20 must also be changed from time to time. That is, this vibration isolator also controls the rate of change in the rotational speed N of the 08M120. At this time, since the relationship between the drive frequency fN and the rotation speed N is not linear, if the relationship between the output of the counter 11 and the rotation speed N is also not linear, it becomes difficult to control the rate of change of the rotation speed N. .

Therefore, the logarithmic conversion circuit 204 (
(see Figure 14), and the output of counter 11 and 08M
120 and the rotational speed N is almost linear (
(See Figure 15).

To be precise, the rotational speed N of 08M120 is not determined to a single value once the output of the counter 11 is determined;
It changes depending on the load applied to 08M120. Therefore, in order to control the rotational speed N of the 08M120, it is necessary to detect the rotational speed N and feed it back to the control circuit. Therefore, the rotation speed of 08M120 is detected by a rotary encoder 17 connected to the rotation shaft of 08M120 and a rotation speed detection circuit 18, and a rotation speed signal vR is fed back. That is, comparator 7, counter 11, DACl 3, U
The speed signal vv and the rotational speed signal v are detected by the feedback of the system composed of the SM control circuit 15.08M120, the rotary encoder 17, and the rotational speed detection circuit 18.
The rotational speed of the USMI 20 is determined so that R and R match.

The acceleration signal Va is converted by the absolute value circuit 9 and the VCO 10 into a pulse having a frequency proportional to the absolute value of Va, and is input to the clock input terminal CK of the counter 11. That is, the counting speed of the counter 11 is equal to the acceleration signal V.
It is proportional to the absolute value of a. As mentioned above, the counter 11
Since the output of 08M120 and the rotational speed N of 08M120 have a nearly linear relationship, the rate of change of the rotational speed N of 08M120 is determined here. The rate of change in rotational speed is nothing but acceleration, and in other words, the above operation is expressed as acceleration signal V
This means that the acceleration of the rotational movement of 08M120 is controlled by a. For example, when the rate of change in the speed of vibration vibration, that is, the acceleration, is large, the frequency of the clock input to the counter 11 becomes high, and as a result, the rate of change in the rotational speed of 08M120 becomes large.

On the other hand, if the acceleration of shaking vibration is small, counter 1
The clock frequency of 08M120 becomes lower, and the rate of change of the rotation speed of 08M120 becomes smaller.

As described above, when the USMI 20 is driven and controlled by the camera shake signal detected by the acceleration sensor, the USMI
The three-dimensional cams 124 fixed to the output shafts 20 rotate at the same time. A roller 125 is in contact with the three-dimensional cam 124, and as the three-dimensional cam 124 rotates, the first structural member 10
Operate 1 up and down. Furthermore, the first structural member 101
As mentioned above, the lens frame 100 and the camera body mechanism block 405 are held in the 08M120.
The camera shake in the vertical direction is corrected by rotation control.

Next, limit sensors 139a, 139b, limit detection circuit 2
1 will be explained using FIGS. 18, 20, and 21. As mentioned above, the three-dimensional cam 12 in vibration-proof operation
There is a limit to the rotation angle of the roller 125 and the cam 124.
If the level difference C is exceeded, vibration-proofing operation becomes impossible. Therefore,
Limit sensors 139a and 139b detect that the limit angle is approached, and output signals S LA+S LB. The signal SLA is output when the limit angle in the CW force direction is approached, and the signal Sta is output when the limit angle in the CCW direction is approached.

However, if the 08M120 is simply stopped when the signal SLA or SLB is output, once the operation has stopped, the operation cannot be resumed and the vibration-proofing operation will be interrupted. Therefore, the limit detection circuit 21 inputs the speed signal vv and causes the 08M120 to pause only when it approaches the limit angle and is about to move to the limit angle.

Suppose now that a shake vibration exceeding the amount of shake that can be corrected is applied (see FIG. 21). The camera rotates downward, and in response, the cam 124 rotates in the CW force direction, eventually approaching the limit angle, and the signal SLA becomes "H". At this time, ■v〉
0, the output Sv of the comparator 213 in the limit detection circuit 21 is “H”.

Therefore, the output SL of the limit detection circuit 21 becomes "L",
08M120 stops. However, when the camera eventually begins to rotate upward, V v < 0, and 08
M120 resumes rotation in the CCW direction. The same applies when the limit in the opposite direction is reached.

Up to this point, we have explained the camera shake prevention operation in terms of vertical correction, and in order to make it easier to understand, we have assumed it to be a simple harmonic motion.However, camera shake is a type of vibration, and analytically it can be interpreted as a simple harmonic motion. Therefore, camera shake can also be corrected by the method of the present invention.

Furthermore, in the explanation so far, we have explained correction in the vertical direction, but since camera shake occurs in both the vertical and horizontal directions, it goes without saying that more complete camera shake correction is possible if both are corrected.

FIG. 23 is a front view of the camera according to the present invention. As described above, the present invention is provided with a control section for correcting blur in the horizontal direction, which is exactly the same as the control section in the vertical direction. A third acceleration sensor 143 and a fourth acceleration sensor 144 that detect acceleration in the left-right direction are disposed and fixed to the arms extending left and right of the holding member 131 below the camera. The respective outputs of the acceleration sensors 143 and 144 are subjected to signal processing through the subtraction circuit of the left and right control section, similarly to the vertical acceleration sensors 117 and 118. Here, since the description overlaps with the description of vertical shake correction, the following description will be omitted, but the second ultrasonic motor 121 is driven and controlled by the signal controlled by the control unit 119.

The second ultrasonic motor 121 includes a cam 12 as described above.
7 is fixed and the guide shaft 128 is inserted into the groove 127a, so the rotation of the second ultrasonic motor 121 causes the guide shaft 128 to move along the inner periphery of the groove 127a.

At this time, since the groove 127a is formed in a cam shape that allows a certain amount of horizontal movement depending on the amount of rotation of the second ultrasonic motor 121, a predetermined horizontal correction can be made using the control signal. There is.

In the explanation so far, vertical camera shake is corrected by rotating the cam 124, and horizontal camera shake Jt
It has been explained that the cam 127 is used for correction. By the way, the amount of camera shake varies from person to person, but in normal photography, the image shake on the screen is about 1 dragon at most. Therefore, the amount of displacement by the two cams for correcting camera shake is small enough to correct the optical axis by 1° to 2°, and camera shake can be corrected.

The first structural member 1 that swings due to the rotation of the three-dimensional cam 124
01 includes a guide shaft 12 that rotationally corrects horizontal shake.
8 is implanted, this guide shaft 128 makes a slight circular arc movement in the vertical direction about the support shaft 130. At this time, some sliding occurs between the cam groove 1278 and the support shaft 130 and guide shaft 1 in FIG. 6(b).
28. As can be seen from the positional relationship of the cam grooves 127a,
Since the guide shaft 128 in FIG. 6(b) has a loose arc-shaped cam groove 127a formed therein, even if the guide shaft 128 makes a slight arc movement up and down due to the rotation of the three-dimensional cam 124, the guide shaft 128 will remain circular. It is formed in an arc shape, and the cam groove 12
7a, it is constructed so that it can slide smoothly without any wobbling, with an extremely small gap, so that no malfunction will occur.

FIG. 6(b) is a view of the periphery of the cam 127 viewed from below the camera. A magnetic sensor 145 and limit sensors 146, 147 are arranged around the cam 127, similar to the three-dimensional cam 124, and output signals for drive control in the same manner as for vertical correction.

In this way, by the rotation of the second ultrasonic motor 121 whose drive is controlled by the control unit 119 according to the amount of vibration in the left-right direction, the first structural member 101 is rotated about the support shaft 130 via the guide shaft 128. The image is rotated left and right to correct blurring.

The camera shake prevention mechanism configured as described above operates, and when the camera shutter is closed and exposure is completed, an anti-shake off signal is input to the sequence control circuit 23 by a signal generating circuit linked to the end of exposure. In response to this, the sequence control circuit 23 generates an anti-vibration on/off signal S. B to “H”
” to “Lm. In response to this, the anti-vibration on/off control circuit 22 changes the preset signal SPR from "H" to "L" at the moment the speed signal vv changes from negative to positive. S P
R-“L” is input to the preset terminal PR of the counter 11, puts the counter 11 in the preset mode, and the USMI
Stop 20.

When the anti-vibration operation is completed, an initialization operation is performed.

A preset signal SPR is input to the sequence control circuit 23, and when it is detected that the preset signal SPR becomes 5PR-“L”, by performing an initialization operation,
Since the roller 125 is brought to the center of the slope of the three-dimensional cam 124, the next vibration-proofing operation can be performed by using the operating stroke of the three-dimensional cam 124 at once.

Furthermore, it goes without saying that this initializing operation can be performed not only on the three-dimensional cam 124 but also on the cam 127 that performs horizontal shake correction using a similar circuit, thereby increasing the degree of freedom in the operating range in the same way as in the vertical direction. - In an eye reflex camera, it is preferable to perform the initializing operation before the mirror is lowered, since the shake of the finder image due to the initializing operation will not be visible to the photographer.

In the explanation, the counter 11 is assumed to have 4 bits, but is not limited to this, and may be 8 bits or 16 bits. Further, in this embodiment, a configuration is described in which both positive and negative power sources are used as the power source, but of course, a single power source is also possible.

FIG. 24 shows another embodiment of the support shaft of the vibration isolation mechanism. 1st
A first rotating shaft 407 is integrated with the structural member 101,
It is rotatably supported with respect to a second rotating shaft 408 . On the other hand, the second rotation shaft 408 is fitted into a support member 409 and supported so as to be rotatable in a direction perpendicular to the plane of the paper. Furthermore, since the support member 409 is fixed to the holding member 131 with screws or the like, the first structural member 101 is rotatable in the X and Y directions about the two rotation axes 407 and 408.

In this way, the support shaft may be spherical as in the above embodiment, or may be provided by dividing the x and y rotation axes.

Next, a second embodiment of the present invention will be described based on FIG. 25. Up to now, in the first embodiment, the viewfinder format of the camera has been explained as a single-lens reflex type, but
The present invention is not limited to single-lens reflex cameras, but extends to all kinds of photographic devices, such as rangefinder compact cameras and still video cameras. Here, a rangefinder type camera will be described as a second embodiment.

The finder frame 412 of the camera has a double structure so as to be linked with zooming. The first exterior member 409 and the finder window 4 maintain a certain gap with the finder frame 412.
10 is attached to the second exterior member 411. Eyepiece frame 412 is attached to a structural member 426 that holds the camera's imaging mechanism. The photographing lens 413 is connected to a mechanism (not shown) so as to perform a series of photographing operations such as autofocus and zoom by a means (not shown), and is attached to the second lens frame member 415. A first lens frame member 414 having a mechanism such as a lens buffer is attached to the lens side tip of the second lens frame member 415.

The first lens frame member 414 and the second lens frame member 415 at the tip on the lens side are attached to the exterior member with a constant gap maintained therebetween.

A support shaft 4 is provided on the rear end side of the camera of the second lens frame member 415.
21 are combined. The rear lid 417 above the optical axis of the structural member 426 is provided with unevenness to prevent light leakage, and the rear lid 417 is kept with a small gap from the structural member 426 by an opening/closing lock member (not shown). and is held by the exterior member. A pressure plate 418 is movably attached to the rear lid 417, and a pressure plate spring 419 causes the structural member 42 to
It is attached so as to press 6.

Next, there is a third exterior member 416 on the bottom side of the camera, which is attached to a holding member 420 that maintains strength together with the second exterior member 411, a rear cover opening/closing lock member, and the like. The holding member 420 engages with the rear M417 at the end on the film surface side, and has projections and depressions formed to prevent light leakage, so that when the rear lid 417 is closed, light does not leak to the film. There is. Further, a ball joint bearing portion similar to that of the first embodiment is formed on the rear end surface of the holding member 420.
The support shaft 421 is freely rotatable both vertically and horizontally, and is held so as not to come off. In addition, the holding member 420 includes
The X-direction blur correction means 422 is also similar to the first embodiment.
and Y-direction blur correction means 423 are fixed.

The X direction blur correction means 422 is connected with a first connection means 424 to the lens frame member 415, and the Y direction blur correction means 423 is connected to a second connection means 425 to the lens frame member 415. connected. In addition, 427a, 4
27b is an acceleration sensor, and 428 is a control unit. Also,
Although two acceleration sensors 427a and 427b are shown in FIG. 25, two acceleration sensors are provided in each of the X and Y directions, as in the first embodiment.

In this way, when camera shake occurs in a lens-shutter camera, the acceleration sensor detects the camera shake, and the control unit 428 uses a signal that is processed to control the X-direction blur correction means 422 and the Y-direction blur correction means 423. It is possible to correct camera shake by controlling the rotation of the lens frame member 415.

When the camera shake correction means is activated, the photographing device moves to the support shaft 4.
12, but at this time, the structural member 426
The position of the pressure plate 418 connected to the rear cover 417 is adjusted by the pressure plate spring 41.
Although the shake correction operation is performed by slightly changing the force of 9, since the pressure plate 418 is constantly pressing against the structural member 426 with the pressure force of the pressure plate spring 419, the pressure plate 418 does not lift up from the structural member 426. This allows the film to be held stably at all times.

In addition, in the above embodiment, the rotation fulcrum is provided below the optical axis of the camera, but if the rotation fulcrum is placed in the opposite direction, that is, near the eyepiece lens, it will feel even more strange. It is possible to create an anti-shake mechanism with less blurring.

Further, in the case of an SLR type finder, the image disappears during exposure, but in the case of a rangefinder camera, the finder image is visible even during exposure, so the effects of the present invention are more remarkable in the rangefinder type camera.

FIG. 26 is a sectional view showing the detailed structure of the rear lid portion of this embodiment. As described above, the rear M429 is engaged with the structural member 433 of the photographing device with a certain gap maintained so as to prevent light leakage.

Further, the pressure plate 432 is pressed against rail-shaped protrusions 433a and 433b disposed above and below the aperture of the structural member 433 with a predetermined force due to the elasticity of the pressure plate spring 430.

The pressure plate spring 430 is fixed to the rear cover 429 with rivets 431. Its detailed structure is shown in FIG. The reason why there is a U-shaped notch in the center of the pressure plate spring 430 extending left and right is to engage a not-shown protrusion provided on the rear cover 429 and fix the pressure plate spring 430 while maintaining its elasticity. It is something.

FIG. 28 shows a diagram when a conventional pressure plate crimping section is used. Conventionally, the pressing surface of the pressure plate has rail-shaped protrusions having a trapezoidal cross section from the camera body above and below the aperture. However, when the camera shake prevention mechanism works and the structural member 433 performs the shake correction operation from several companies, the pressure plate 432 and the rail protrusion 433a-
As shown in the figure, the pressure plate 432 was pushed at the corner edge, resulting in severe wear and durability problems.

In the present invention, as shown in FIG.
By making the cross-sections of 33a and 433b R-shaped, even if the structural member 433 vibrates due to the anti-shake mechanism of the camera, it is possible to smoothly follow the pressure plate spring 430, and the compression force of the pressure plate spring 430 is reduced. This has the effect of reducing the load on the anti-shake mechanism caused by vibration.

Note that FIG. 29(a) shows a rail-shaped protrusion 433a with an arcuate tip as in the present invention.

433b and the pressure plate 432, and shows the state before starting the camera shake prevention operation. 29th
Figure (b) shows a state in which the pressure plate 432 is tilted by an angle θ due to the camera shake prevention operation being performed and the rail-shaped protrusions 433a and 433b rotating around a support shaft (not shown). At this time, since the tips of the rail-shaped projections 433a and 433b are arcuate as in the present invention, the pressure plate 432 is not damaged by the corner edges as shown in FIG. 28.

Next, FIG. 30 shows another embodiment of the pressure plate section.

435 is a film guide rail protruding from the structural member 433. Outside the aperture of the film guide rail 435 are four approximately spherical pressure plate receivers 436.
a, 436b, 436c.

436d is arranged with a predetermined step difference from the film guide rail 435. Fig. 31 shows the structural member 4.
A cross-sectional view of No. 33 is shown. These pressure plate receivers 436a, 436
b, 436c, and 436d may be integrally disposed on the structural member 433 and may be formed by molding, or may be integrally fixed and formed by separate parts.

FIG. 32 shows yet another embodiment of the pressure plate position regulating section.

The pressure plate 432 has spherical protrusions 437a, 437b, and 437c near each corner of the surface facing the film on the aperture side and in contact with the structural member 433.
, 437b are arranged. A flat surface (not shown) is formed in the portion of one structural member 433 that the projections 437a, 437b, 437c, and 437b come into contact with.

In this way, by making one of the abutting portions between the pressure plate 432 and the structural member 433 spherical, the pressure plate 432 is extremely effective in both the X direction camera shake correction operation and the Y direction camera shake correction operation. Smooth tracking is possible. In recent years, advances in plastic molding technology have made it possible to mold spherical protrusions while maintaining extremely high flatness, and the invention of the contact surface of the pressure plate 432 of the present invention is easy and highly effective.

In addition, the present invention detects camera shake and activates a camera shake prevention mechanism using a drive circuit to correct camera shake. Hold it so that it can swing from the member,
In a camera that reduces camera shake, the same effect can be obtained by making the contact portion of the pressure plate semispherical.

[Effects of the Invention] As described in detail above, according to the present invention, by making the actuator operation start timing coincide with the time when the speed of vibration vibration is zero (0), there is no need for sudden acceleration, which was previously the case. Since it is only necessary to gradually accelerate the vibration in accordance with the acceleration of the blurring vibration, it is possible to provide an optical system vibration isolator that does not generate ringing and can perform accurate vibration damping operation immediately after the start of operation.

[Brief explanation of drawings]

The figures are for explaining the present invention in detail. Figure 1 is a longitudinal side view schematically showing the internal structure of the camera, Figure 2 is an exploded perspective view showing the exterior structure of the camera, and Figure 3 is a support FIG. 4(a) is an exploded perspective view showing a roller and a roller bearing for holding the roller shaft. FIG. 4(b) is an exploded perspective view illustrating the shaft and its bearing surface. 5(a) is a perspective view showing the structure of the three-dimensional cam fixed to the first ultrasonic motor, and FIG. 5(b) is a diagram illustrating the operating state of the roller on the three-dimensional cam. , Figure 6(a) is the second
A perspective view showing the structure of a cam fixed to the ultrasonic motor of
FIG. 6(b) is a plan view showing the peripheral part of the cam, and FIG.
The figure is a diagram explaining the guide shaft that fits into the groove of the cam in Figure 6, Figure 8 is an overall block diagram of the control section, Figure 9 is an input/output waveform diagram of the integrating circuit, and Figure 10 is the absolute value circuit. Figure 11 is a block diagram of the overflow prevention circuit, Figure 12 is a diagram showing the human output characteristics of the DAC, Figure 13 is a diagram of the USM on/off circuit, and Figure 14 is the USM control circuit. Fig. 15 is a characteristic diagram of the USM control circuit, Fig. 16 is a diagram of the U
FIG. 17 is a characteristic diagram showing the relationship between the driving frequency and rotational speed of the USM; FIG. 18(a) is a side view showing the arrangement of the rotary encoder and limit sensor; 18(b) is a top view of FIG. 18(a), FIG. 19 is a diagram showing an example of the output pulse of the rotary encoder, FIG. 20 is a configuration diagram of the limit detection circuit, and FIG.
The figure is a signal waveform diagram of each part explaining the operation of the limit detection circuit.
Figure 22 is a configuration diagram of the vibration isolation on/off control circuit, Figure 23 is a diagram showing the installation state of the acceleration sensor that detects acceleration in the left and right direction, and Figure 24 is another embodiment of the support shaft of the vibration isolation mechanism. FIG. 25 is a vertical side view schematically showing the internal structure of a camera according to another embodiment of the present invention, and FIG.
The figure is a longitudinal side view showing the detailed structure of the rear lid part, Fig. 27 is a perspective view showing the detailed structure of the pressure plate spring, Fig. 28 is an explanatory diagram when using a conventional pressure plate crimping part, and Fig. 29 is the rail. FIG. 30 is a diagram showing another embodiment of the pressure plate portion, FIG. 31 is a cross-sectional view of the structural member in FIG. 30, and FIG. 32 is a diagram showing yet another pressure plate position. It is a figure showing an example of a regulation part. 117.118 Acceleration sensor, 134 Exterior member, 138 Bottom plate, 409, 411 Exterior member, 100 Lens frame, 101, 102.103
... Structural member, 120.121 ... Ultrasonic motor,
129... Pressing plate, 130... Support shaft, 131...
- Holding member, 3... Subtraction circuit, 5... Precision circuit, 6
...Comparator, 9...Absolute value circuit, 10...
VCo, 11... U/D counter, 12... Overflow prevention circuit, 13... DAC, 14... USM
On/off circuit, 15...USM control circuit, 17...
- Rotary encoder, 18... Rotation speed detection circuit, 21... Limit detection circuit, 22... Anti-vibration on/off control circuit, 23... Sequence control circuit.

Claims (1)

[Scope of Claims] A speed detecting means for detecting the speed of the shaking vibration of the optical system; and a speed detecting means for detecting the speed of the shaking vibration of the optical system; The present invention is characterized by comprising an actuator to be driven, and actuator operation start timing means for starting the operation of the actuator when the speed of the shake vibration becomes zero after inputting a signal to start the shake vibration prevention operation. Anti-vibration device for optical system.