JPH05150194A - Vibration prevention device - Google Patents

Abstract

PURPOSE:To prevent the consumption of a large current which is possibly generated in the state transition of a mechanical holding mechanism to make a screen hard to see or break the holding means and optical correcting means. CONSTITUTION:This vibration prevention device is provided with the mechanical holding means 14 which mechanically holds the optical correcting means 2a, 2b, and 3 at specific positions and electric holding means 6a, 6b, and 18 which operate in the state transition of the mechanical holding means 14 to hold the optical correcting means at the specific positions; and an optical holding means is held or released from the holding state. When the mechanical holding means has the state transition, the electric holding means are put in operation to make the holding of the optical correcting means by the mechanical holding means smooth or prevent the optical correcting means from shifting from the specific position owing to gravitation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a shake prevention device incorporated in or attached to a photographing section of a silver salt camera, an electronic still camera, a video camera or the like.

Here, the above-mentioned electrical holding means is means for holding the optical correction means at a predetermined position while energizing the means, and the mechanical holding means is the means. The optical correction means is continuously held at a predetermined position without being energized to. The mechanical holding means does not involve electrical control at all, but may also be accompanied by electrical control when the optical correction means is held in a predetermined position or when the holding is released. Shall be included.

[0003]

2. Description of the Related Art In recent years, the automation of photographing devices such as still cameras and video cameras has advanced, and those equipped with an automatic exposure and automatic focus adjustment mechanism have been widely put into practical use. Some techniques for realizing a shake correction function for correcting image shake caused by shake of the entire apparatus have been put into practical use.

The shake preventing device having the shake correcting function generally includes a shake detecting means for detecting shake of the entire apparatus, an optical correcting means for correcting image shake caused by the shake, and the optical correcting means. Drive means for driving, control means for controlling the drive means by calculating an image shake correction amount according to the output of the shake detection means, and the drive means (shake optical correction means) at a predetermined position mechanically. And holding means for holding.

The shake detecting means includes an angular accelerometer, an angular velocity meter, or an angular displacement meter, and the optical correcting means includes a variable apex angle prism.

[0006]

However, in the above-described conventional example, the stable position of the variable apex angle prism, which is the optical correction means, when it is not controlled is a predetermined position by the holding means (due to the influence of gravity, etc.). When it is significantly different from (neutral position) (usually the transparent plate described later is in a V shape because the liquid inside is affected by gravity), the holding means from the holding state to the holding release state, Alternatively, when the hold release is changed to the hold state, the shooting screen moves greatly, or the shooting screen is discontinuous due to the collision of the variable apex prism with the holding means (when holding is changed to the hold state). As a result, the shooting screen becomes unsightly, and the holding means and the variable apex angle prism are damaged.

Further, at the time of transition from the holding state to the holding release (specifically, at the time of starting the shake correction immediately after the holding release), a large current is instantaneously applied to the driving means in order to bring the variable apex angle prism to, for example, the neutral position. There was a problem that it had to be flushed.

The object of the present invention is to make the screen unsightly, which may occur when the state of the mechanical holding means changes.
An object of the present invention is to provide a shake prevention device capable of preventing the holding means and the optical correction means from being damaged and consuming a large amount of current.

[0009]

The present invention comprises a mechanical holding means for mechanically holding an optical correction means in a predetermined position,
An electrical holding means is provided which operates when the state of the mechanical holding means changes and holds the optical correction means at a predetermined position.

[0010]

When the state of the mechanical holding means is changed such that the optical holding means is held or released from the held state, the electrical holding means is operated to hold the optical correction means by the mechanical holding means. The smoothing is performed so that the optical correction means does not collide with the mechanical holding means, and the optical correction means is prevented from shifting from a predetermined position due to gravity or the like.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the illustrated embodiments.

FIG. 1 is a view showing the schematic arrangement of a shake preventing apparatus according to the first embodiment of the present invention.

The outer peripheries of the transparent plates 2a and 2b formed of two glass plates facing each other are sealed by a film 3, and a liquid having a high refractive index (not shown) is sealed in the space sealed by the film 3. ) Is satisfied, and a variable apex angle prism is configured, and the variable apex angle prism includes frame bodies 4a and 4b.
The transparent plates 2a and 2b are clamped by the pitch shaft 5a and the yo-yo.
It is held so as to be rotatable around the shaft 5b.

A flat coil 6a is fixed to one end of the front frame 4a, and permanent magnets 7a and yokes 8a and 9a are arranged facing each other on both sides thereof to form a closed magnetic circuit. ing. Further, an arm portion 11a having a slit 10a is formed at a position facing the coil 6a of the frame body 4a, and a light emitting element 12a and a light receiving element 13a are arranged on both sides thereof so as to face each other. Here, the light emitting element 12a is an infrared light emitting element such as IRED, and the light receiving element 13a is a photoelectric conversion element such as PSD whose output changes depending on the position of the spot of the received light beam.

The light beam emitted from the light emitting element 12a is transmitted to the light receiving element 13a after passing through the slit 10a, and the slit 10a moves between the light emitting element 12a and the light receiving element 13a.
The movement amount and movement direction of the frame body 4a can be obtained by an electric signal.

The frame bodies 4a and 4b are placed at the neutral position (the transparent plate 2
The lock lever 14 which is locked at a position where a and 2b are perpendicular to the optical axis) is supported by a member (not shown) so as to be movable in the direction of arrow A in the drawing, and each frame body is provided on the front surface thereof. Four
Fitting groove 1 for locking the locking pins 16a, 16b of a, 4b
7a and 17b are formed.

The photo interrupters 20a and 20b for detecting the position of the lock lever 14 are lock lever 14
The ON / OFF state of the shake control is detected depending on whether or not the protrusion 17c provided on the light shields the optical path.

The shake detectors 15a and 15b for detecting shakes in the pitch direction and the yaw direction are attached to a supporting portion of the device so as to detect the shake amounts of the entire device in the pitch direction and the yaw direction. There is.

The locking pins 16a and 16b mentioned above are
The frame members 4a and 4b are attached to each other at an angle of 45 degrees, and when the lock lever 14 advances toward the frame members 4a and 4b side, they are engaged with the fitting grooves 17a and 17b and their positions are regulated. , The variable apex angle prism is held.

Although not shown in the drawing, the flat coil 6b, the permanent magnet 7b, and the yokes 8b and 9b are also provided on the yaw side, respectively.
Means for generating an electromagnetic drive force and a slit 10
b, arm 11b, light emitting element 12b, and light receiving element 13b are respectively provided with means for detecting the moving position, and function in the same manner as the operation on the pitch side.

FIG. 2 shows the shake detectors 15a and 15b described above.
It is a figure which shows the internal structure of.

A liquid 152 having a high specific gravity is provided inside the outer cylinder 151.
The liquid 152 is filled with the sensing blade 15
The shaft 3 is attached to the holding arm 154 fixed to the outer cylinder 151.
It is held rotatably around 55. A slit-shaped reflecting surface 156 is provided near the center of the sensing blade 153.
Is provided.

The reflecting surface 1 is provided outside the outer cylinder 151.
A light emitting element 157 and a light receiving element 158 are arranged toward 56, and the light flux emitted from this light emitting element 157 is reflected by the reflecting surface 156 and is irradiated on the light receiving surface of the light receiving element 158. Here, the light emitting element 157 is an infrared light emitting element such as IRED, and the light receiving element 15
Reference numeral 8 denotes a photoelectric conversion element such as PSD whose output changes depending on the position of the spot of the received light beam.

Next, the shake detector 15 having the above structure
The operations of a and 15b will be described step by step.

When shake occurs in the entire apparatus due to shake of the hand holding the camera, shake detectors 15a, 15b
The inner outer cylinder 151, the holding arm 154, the light emitting element 157, and the light receiving element 158 move in the swing direction together with the device. However, the high specific gravity liquid 152 and the sensing blade 1 inside
The reflecting surface 156 provided at 53 and its central portion tends to stand still with respect to absolute coordinates due to its own inertia. Therefore, a relative angle depending on the shake amount is generated between the outer cylinder 151 and the sensing blade 153, and the light emitting element 15 is caused by this relative angle.
The position of the spot formed on the light-receiving surface of the light-receiving element 158 of the light beam emitted from the laser beam 7 and reflected by the reflecting surface 156 changes, and the light-receiving element 158 outputs a signal corresponding to the amount of change.

Therefore, the output of the light receiving element 158, that is, the output of the shake detectors 15a and 15b becomes a value indicating the magnitude of movement of the frame bodies 4a and 4b around the respective shafts 5a and 5b. This signal is input to the control circuit 18, where it is multiplied by an appropriate multiplier and converted into the amount of displacement of the apex angle required to remove this shake by the variable apex angle prism.

On the other hand, the rotation angle around the axes 5a and 5b of the transparent plates 2a and 2b facing each other, which are the constituent members of the variable apex prism, that is, the variation of the pitch of the variable apex prism and the apex angle in the yaw direction causes light emission. The luminous flux emitted from the element 12a (12b) passes through the slits 10a (10b) attached to the arm portions 11a (11b) of the frame bodies 4a and 4b that rotate integrally with the transparent plates 2a and 2b facing each other, and is received. Elements 15a, 1
It is detected by the movement of the spot position on the light receiving surface when the light beam is incident on 5b. The light receiving element 13a (13b) transmits to the control circuit 18 an output according to the amount of movement of the spot, that is, the magnitude of displacement (displacement amount) of the apex angle of the variable apex angle prism.

The control circuit 18 calculates the difference between the size (displacement amount) of the apex angle obtained by the above-described calculation and the size of the apex angle of the variable apex angle prism at the present time, and this is calculated by the coil 6
It is transmitted to the coil drive circuit 19 as a drive command signal of a (6b). The coil drive circuit 19 supplies a drive current according to the coil drive command signal to the coil 6a (6b) to generate a coil drive force by an electromagnetic force between the coil 6a (6b) and the permanent magnet 7a (7b).

The variable apex angle prism is rotated about the axes 5a and 5b by this coil driving force, and is deformed so as to match the magnitude of the apex angle calculated above. That is, the variable apex angle prism uses the value of the apex angle calculated for correcting the shake as a reference signal, and the current value of the apex angle as a reference signal.
A feedback control system that uses a feedback signal is driven to perform shake correction control.

Next, the mechanical operation when starting / stopping the shake correction will be described.

When the shake correction is not performed, the frame 4a,
4b is mechanically held and the variable apex angle prism is configured to be locked at the midpoint of its variable range. That is, the locking of the movement on the pitch side is performed by locking the frame body 4a, and the locking of the movement on the yaw side is performed by locking the frame body 4b.

The pitch side locking pin 1 is provided on the front frame 4a.
6a is formed integrally so that it is parallel to the axis 5a and the tip of the pin is positioned at an angle of 45 degrees above the optical axis. Similarly, a yaw-side locking pin 16b is formed integrally with the rear frame body 4b so that the tip of the pin is parallel to the shaft 5b and the tip of the pin is positioned at an angle of 45 degrees above the optical axis. That is, the frame body 4
The a and 4b are configured such that the frame bodies having the same shape are rotated 90 degrees from each other and turned upside down to face each other. As a result, both parts are made into common parts, and the cost is reduced.

As described above, the lock lever 14 is mounted so as to be movable in the horizontal direction as shown by the arrow A in FIG. 1, and is moved to the direction of the arrow A, that is, the position advanced to the frame bodies 4a and 4b. By moving to, the fitting grooves 17a and 17b fit into the locking pins 16a and 16b, respectively, and lock them.

As a result, the operations of the variable apex angle prism in the pitch direction and the yaw direction are simultaneously locked.

On the contrary, the lock lever 14 is moved in the direction opposite to the arrow A to move the frame members 4a, 4b (locking pins 16a, 16).
By releasing the locking by the fitting grooves 17a and 17b in b), the respective frame bodies 4a and 4b are brought into a free state, the variable apex angle prism is brought into an operable state, and shake correction is possible. ..

At this time, when the shake correction is possible, the protrusion 17c turns on / off the photo interrupters 20a and 20b by the movement of the lock lever 14, and the control circuit 18 controls the start / stop of the shake correction operation.

Next, the procedure for starting / stopping the shake correction operation in the control circuit 18 will be described with reference to the flowcharts of FIGS.

First, the start of the shake correction operation will be described with reference to FIG. [Step 41] The fitting groove 17a of the lock lever 14
Locking pin 16 attached to frames 4a and 4b at 17b
The photo interrupter 20b is turned off before the lock lever 14 is operated in the direction opposite to the arrow A from the locked state (mechanical lock) of the variable apex angle prism fitted with a and 16b, and the mechanical lock is released. However, since it is instructed to start the shake correction by turning off the photo interrupter 20b, the process proceeds to step 42. "Step 42" At this point, the shake detector 15 is still
Coil 6a, through coil drive circuit 19 for holding the variable apex angle prism, which is an optical correction means, at the neutral position (predetermined position by the lock lever 14) without using the outputs of a and 15b for control. Energization of 6b is started (electrical lock is applied). [Step 44] When the lock lever 14 is operated in the direction opposite to the arrow A, the photo interrupter 20a is operated.
Is turned on, but it is assumed that the unlocking is completed by turning on the photo interrupter 20a, and the shake detector 15
A normal shake correction operation based on the outputs of a and 15b is started.

Next, a case where the shake correction operation is stopped will be described with reference to FIG. [Step 51] The transition from the shake correction operation state by the variable apex angle prism to the locked state of the variable apex angle prism is realized by operating the lock lever 14 in the direction of arrow A as described above. When the photo interrupter 20a is started before the mechanical locking is started.
It becomes FF, and the control circuit 18 uses the photo interrupter 2
Since it is instructed to stop the shake correction by turning OFF 0a, the process proceeds to step 52. "Step 52" Here, the shake detectors 15a and 15b
Centering signal instead of the output of the coil drive circuit 19
To output to the coils 16a and 16b, and the centering of the variable apex angle prism is started. "Step 53" The variable apex angle prism, which is an optical correction means, is held in the neutral position by the centering signal (electrically locked). [Step 54] When the lock lever 14 is further operated in the direction of arrow A, the photo interrupter 20b is turned off.
However, if the photo interrupter 20b is turned on, it is determined that the lock lever-4 has locked or the lock (mechanical lock) of the variable apex angle prism has been completed, and the process proceeds to step 55. [Step 55] The energization by the coils 6a and 6b via the coil drive circuit 19 is stopped (the above electrical lock is stopped), and the shake correction operation is stopped.

(Second Embodiment) FIG. 5 is a view showing the schematic arrangement of a shake preventing apparatus according to the second embodiment of the present invention.
The same parts as those in FIG. 1 are designated by the same reference numerals.

The difference from the first embodiment is that the frame 4
Locking member 22 having fitting grooves 20a, 20b into which locking pins 16a, 16b attached to a, 4b are fitted
Is driven by the motor 21 and the shake correction operation is started / stopped by an external operation switch (not shown).

Upon detection of ON / OFF of the external operation switch, start / stop of the shake correction in steps 41 and 51 shown in FIGS. 3 and 4 is started, and the determination of steps 43 and 54 is performed by the locking member 22. The increase of the motor current value due to the collision of the current is performed by a detection circuit (not shown).

The other operations are the same as those in the first embodiment, and the description thereof will be omitted.

According to each of the above embodiments, the lock lever 14
When the state of (or the locking member 22) changes, that is, when the state changes from the locked state to the unlocked state or from the unlocked state to the locked state, the variable apex angle prism, which is an optical correction means. Is electrically locked to the neutral position (electrically locked), unnecessary movement of the variable apex angle prism due to gravity at the start / stop of the shake correction operation and the lock lever 14 (or It is possible to prevent the variable apex angle prism from colliding with the locking member 22) and to stabilize the photographing screen.

The lock lever 14 (or the locking member 2)
Since it is not necessary to supply a large amount of drive current to the coils 16a and 16b after the completion of the transition from the locked state to the unlocked state of 2), current consumption can be suppressed. Also, when the state changes from the unlocked state to the locked state,
The variable apex angle prism is a lock lever 14 (or locking member 2
Since it is kept smooth by 2), it has an effect of improving durability.

(Modification) According to the present embodiment, the optical correcting means has a variable apex angle prism as an example, but the optical correcting means is not limited to this, and the optical correction is of the inertial pendulum type. It may be provided with a means or a shake preventing device having a shift type optical correcting means for performing shake correction by shifting in a plane perpendicular to the optical axis.

[0047]

As described above, according to the present invention,
A mechanical holding means for mechanically holding the optical correction means at a predetermined position; and a mechanical holding means that operates when the state of the mechanical holding means changes,
An electrical holding means for holding the optical correction means at a predetermined position is provided, and the electrical holding means is held when the state of the mechanical holding means is changed to hold or release the optical holding means. Is operated so that the optical correction means can be smoothly held by the mechanical holding means, and the optical correction means is prevented from being displaced from a predetermined position due to gravity or the like. Therefore, when the state of the mechanical holding means changes, the screen becomes unsightly,
It is possible to prevent the holding means and the optical correction means from being damaged and consuming a large amount of current.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a shake prevention device according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a specific configuration example of the shake detector of FIG.

3 is a flow chart showing a procedure at the start of a shake correction operation of the control circuit of FIG.

4 is a flowchart showing a procedure when the shake correction operation of the control circuit of FIG. 1 is stopped.

FIG. 5 is a diagram showing a schematic configuration of a shake prevention device according to a second embodiment of the present invention.

[Explanation of sign]

 2a, 2b Transparent plate 3 Film 4a, 4b Frame body 6a, 6b Coil 14 Lock lever 15a, 15b Shake detector 18 Control circuit 20a, 20b Photo interrupter 21 Motor 22 Locking member

Claims (1)

[Claims] 1. A shake detection means for detecting shake applied to an apparatus, an optical correction means for correcting image shake caused by the shake, and a drive signal calculated on the basis of a signal from the shake detection means. Driving means for driving the optical correction means, mechanical holding means for mechanically holding the optical correction means at a predetermined position, and operating when the state of the mechanical holding means changes, An anti-vibration device having an electrical holding means for holding the device at a predetermined position.