JPH0384507A - Blurring correcting lens barrel - Google Patents

Abstract

PURPOSE:To eliminate the influence of the backlash of a gear mechanism and to obtain the blurring correcting lens barrel which can be improved in operation accuracy by providing pressing means which press and move a blurring correcting lens against the energizing forces of guide energizing means at positions opposite the guide energizing means. CONSTITUTION:A lens frame 10 is provided with pressure pins 21x and 21y which project longitudinally (y direction) and laterally (x direction) to penetrate a lens holding frame 9 and energizing plates 22x and 22y, which are pressed so that their head parts are energized by a leaf spring 23 in the (x) and (y) directions. The pressure pins 21x and 21y have their tip parts pressed by driving levers 20x and 20y in the opposite direction from the energizing direction of the leaf spring 23, so that the lens frame 10 is positioned. Consequently, the operation quantity of a driving mechanism which includes the pressing means is converted by 100% into the operation quantity of a blurring correcting lens at all times and a correction quantity can be controlled with high accuracy.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a camera lens barrel having a correction lens movable in a direction perpendicular to an optical axis in order to correct image blur such as camera shake.

[Conventional technology]

A camera lens barrel is known that can correct image blur by using a part of the lens that makes up the photographic lens as a blur correction lens and moving this lens in a direction perpendicular to the optical axis, thereby suppressing blur. ing. Generally, in a drive mechanism for a blurring correction lens in such a blurring correction lens barrel, a gear mechanism such as a reduction gear is included in a driving force transmission system from a drive motor to a blurring correction lens. When this gear mechanism is included, the backlash of each gear affects the operational accuracy of the mechanism and becomes an obstacle to improving the correction accuracy.

[Problem to be solved by the invention]

The present invention has been devised in view of the technical problems related to the lens drive mechanism for blur correction as described above, and to effectively solve the problems. Therefore, an object of the present invention is to provide a camera shake correction lens barrel that eliminates the influence of backlash in a gear mechanism, and allows the operation of the drive mechanism to directly correspond to the operation of the camera shake correction lens, thereby increasing the accuracy of its operation. .

[Means to solve the problem]

The image stabilization lens barrel according to the present invention solves the problems of the prior art as described above, and has the following configuration in order to achieve the object. That is, in a shake correction lens barrel equipped with a shake correction lens that can be adjusted and moved in a direction perpendicular to the optical axis of the photographic optical system in order to correct camera shake during shooting, the above-mentioned motion is applied between two opposing surfaces perpendicular to the optical axis direction. a regulating means for regulating the movement of the image stabilizing lens; and a regulating means for urging the image stabilizing lens in at least two directions toward the optical axis and intersecting with each other on the optical axis, and the image stabilizing lens biasing each other. a guide biasing means for mutually guiding movement; and a pressing means provided at respective positions opposite to the guide biasing means for pushing and moving the blurring correction lens against the biasing force of the mutual guide and biasing means. We are prepared.

[Action and effect of the invention]

In the image stabilization lens barrel according to the present invention, the movement direction of the image stabilization lens is regulated between two opposing surfaces, and since the two opposing surfaces are perpendicular to the optical axis, the image stabilization lens is always aligned with the optical axis. Perform adjustment movements while maintaining a vertical posture. This adjustment movement is caused by the difference between the urging force of the guide and urging means and the pressing force of the pressing means, and the guiding and urging means form a pair whose urging forces intersect on the optical axis, and the pressing means also Since a pressing force that faces the pair and intersects on the optical axis is applied to the blurring correction lens, the blurring correction lens can be positioned by these two portions in different directions. Since the urging force of the guide and urging means is always acting on the pressing force of the pressing means, for example, a gear mechanism having a bassocrano 7 in the driving force transmission system is used to provide the driving force to the pressing means. Even if they are included, the biasing force will always act in one direction in the meshed state, and "backlash" or "play" will not occur. That is, the amount of operation of the drive mechanism including the pressing means is always 100% converted into the amount of operation of the blur correction lens, and the amount of correction can be controlled with high precision.

【Example】

A preferred embodiment of the present invention will be described below with reference to FIGS. 1 to 15. In the present embodiment shown in FIG. 1, the operation when zooming is performed will be explained. When the zoom operation ring 3 provided on the outermost periphery of the lens barrel is rotated, the rotation is transmitted to the zoom cam ring 6 via the guide pin 44 engaged with the operation ring 3, and the zoom cam ring 6 rotates. . A spiral cam groove 6a is formed in the zoom cam ring 6. On the other hand, a straight groove 2a is formed in the fixed barrel 2 in the optical axis direction, passing through the fixed barrel 2 in its thickness direction. The 1st and 4th group moving frame 7 is located on the inner circumferential side of the fixed barrel 2.
A guide pin 45 is disposed on the outer peripheral surface of the movable frame 7 and protrudes outward in the radial direction, passes through the straight groove 2a of the fixed cylinder 2, and engages with the cam groove 6a of the zoom cam ring 6. It is set up. Therefore, by rotating the zoom cam ring 6,
The 1.4th group moving frame 7 performs a rectilinear movement in the optical axis direction. By a mechanism completely similar to this, the second group moving frame 8 and the blur correction lens holding frame 9 move linearly in the optical axis direction. 2b is a rectilinear groove formed in the fixed barrel 2, 6b and 6c are cam grooves of the zoom cam ring 6, and 46 is a cam i provided protruding from the second group moving frame 8.
A guide pin 47 that engages with the cam groove 6b is a guide pin that projects from the blur correction lens holding frame 9 and engages with the cam groove 6c. As each of the moving frames 7, 8 and the holding frame 9 move in a straight line, the drive lever 20 (see Fig. 2) and the interlock 1/bar 24, which will be described later, are guided by the long groove 20a while remaining integral in the rotational direction. It slides in the optical axis direction and does not hinder movement of the correction lens holding frame 9 in the optical axis direction. Next, in this embodiment shown in FIG. 1, auto focusing (AF)
This will be explained in the case of Due to the driving force from the camera body,
AF coupler 41 rotates. This rotation is caused by the AF gears 42 and 43 and the focus operation ring 4.
The focus operation ring 4 is decelerated by the inner gear 4a of
Rotate. A straight groove 4b extending in the optical axis direction is formed in approximately the front half of the inner circumferential surface of the focus operation ring 4. And just inside facing the inner peripheral surface is the focus lens frame 5.
is located. A guide pin 48 is provided protruding from the outer peripheral surface of the focus lens frame 5, and is engaged with the straight groove 4b of the focus operation ring 4. Therefore, the rotational force of the focus operation ring 4 is directly transmitted to the focus lens frame 5, and the rotation force of the focus operation ring 4 is directly transmitted to the focus lens frame 5.
The frame 5 rotates together with the operating ring 4 in such a manner that the frame 5 is allowed to move in the optical axis direction. As shown in the figure, since the threaded portion 5a of the focus lens frame 5 and the threaded portion 7a of the first and fourth group moving frames 7 are screwed together, the rotation of the focus lens frame 5 is caused by the rotation of the first and fourth group moving frames 7. Focusing is performed by extending and retracting the focus lens frame 5. In the case of manual focusing, the driving force transmission system (not shown) from the camera body side driving force to the AF coupler 41 is disconnected by switching between auto and manual, and the focus operation ring 4 is manually rotated. . 1 to 4 show a lever drive type blur correction drive mechanism as a first embodiment. The vibration reduction lens holding frame 9 is fitted with a vibration reduction lens frame 10 for holding the vibration reduction lens 11 provided closest to the object side in the lens group. It is sandwiched between vertical and mutually opposing surfaces 9a and 9b, and is movable in the direction perpendicular to the optical axis, but is restricted from moving in the optical axis direction. Figure 2 shows the image stabilization lens 11, image stabilization lens holding frame 9, and image stabilization lens frame 1 shown in Figure 1.
0 is a diagram showing the relationship between other peripheral mechanisms as seen from the objective side. The lens frame 10 has press pins 21x, 21 that protrude vertically (X direction) and horizontally (X direction) and penetrate the lens holding frame 9.
y (the correction mechanism in the X direction is represented by adding X to the reference number, and the correction mechanism in the X direction is represented by adding y to the reference number) and biasing plate 2
2x and 22y are provided in contact with each other, and the biasing plate 22X
, 22Y have respective heads pressed by leaf springs 23 so as to be biased in the X direction and the X direction. On the other hand, the press bottle 21x. The tip of the lens 21y is pressed by the drive levers 20x and 20y in a direction opposite to the biasing direction of the leaf spring 23, thereby positioning the lens frame 10. In FIG. 3, a drive motor 29, an interlocking gear 25
．． 26.27, one set of the system of the light shielding plate 30 and the photoink clubter 31 is shown, but one set of this system is provided in each of the X direction and the X direction. Drive motor 29
When is driven, the interlocking lever 24 rotates via the interlocking gears 25, 26, 27. Since the interlocking lever 24 is engaged with the drive lever 20 held by the shake correction lens holding frame 9 through the long groove 20a, the drive lever 20 also rotates as the interlocking lever 24 rotates, and the press pin 21 is pushed in. For example, when the pressing pin 2ix in the X direction is pushed in, the image stabilization lens frame 10
moves in the X direction against the urging force of. At this time, regarding the pressing pin 21y and the biasing plate 22Y in the X direction, the contact surface of the shake correction lens frame 10 that the pressing pin 21y and the biasing plate 22y contact is formed into a plane parallel to the X direction. , the blur correction lens frame 10 can be slid. When the rotation direction of the drive motor 29 is reverse rotation, the interlocking lever 24 and the drive lever 2o also rotate in the reverse direction, and the blur correction lens frame IO also moves in the opposite direction in the X direction. The same applies to the correction operation in the X direction. As described above, the structure for driving the image stabilization lens frame 10 in the X direction or in the By adopting the push-in configuration, the backlash of the gear part in the drive force transmission mechanism can be constantly absorbed, and the correction operation of the shake correction lens frame 10 that follows the operation of the drive mechanism is
Since "play" is eliminated, the precision of the movement can be improved. The drive motor 29 is a pulse motor, and as shown in FIG. 3, its rotation is reduced in speed and transmitted to the interlocking lever 24 via interlocking gears 27, 26, 25. The reduction ratio is set so that the gear 25 does not rotate more than 360° even when the shake correction lens frame 10 is driven to a full stroke. Further, a light shielding plate 30 is fixed to the gear 25 coaxially therewith. The light shielding plate 30 rotates in synchronization with the gear 25 to form a slit in one place that allows light to pass through the photointerrupter 3 (to obtain its output) only when the image stabilization lens frame 10 is at the center of the optical axis. Therefore, by rotating the pulse motor 29 in the reverse direction after driving the image stabilization lens frame 10 and stopping the pulse motor 29 at the position where the output of the photo interrupter 31 is, the image stabilization lens frame 10 can be corrected. It can be returned to the initial position by the amount O. Fig. 4a shows the photointerrupter 3.
1 and the slit of the light-shielding plate 30 are deviated by an angle θ, and FIG. 4b shows a state in which the position of the photo ink clubter 31 and the slit match. FIG. 5 shows a multi-rotation cam type as a second embodiment of the shake correction drive mechanism. In the second embodiment, the interlocking lever 24. and drive cam 20. are connected by a so-called "koban connection (column guide)". That is, at the joint,
Interlocking lever 24. has a non-circular cross section such as an ellipse or an oblong, and the interlocking lever 24. For the rotation of the drive cam 20. rotates integrally, but axial sliding is allowed. Drive cam 20. The cam profile has a spiral stepped cam profile formed around its center of rotation, and its radial dimension changes smoothly along the axial direction. Cam follower 21. has one end in contact with the cam profile, passes through the image stabilization lens holding frame 9t, and has the other end in contact with the image stabilization lens frame 10. is in contact with. Image stabilization lens frame 10. receives an urging force from the opposite side in the radial direction as in the first embodiment. A male screw 20a= is formed at the tip of the drive cam 20, and the blur correction lens holding frame 9! Female screw 12 formed at the tip of
．． By screwing into the drive cam 20., the interlocking lever 24.degree. moves in the optical axis direction, and the cam follower 21. will exercise according to the cam profile. As a result, the shake correction lens frame 10° moves in the radial direction and its position is adjusted. The pitch of this male screw 20a is
It is the same as the pitch of the helix in the cam profile. FIGS. 6 and 7 show a screw type as a third embodiment of the shake correction drive mechanism. In the third embodiment, the interlocking lever 2
4. Helical gear 61. are combined into small pieces. A helical gear 363 that changes the rotation direction by 90 degrees is screwed into the gear 61t. The direction of the rotation axis of the gear 363 is perpendicular to the optical axis of the photographic optical system. Gear 36. A drive shaft 353 is coupled to the drive shaft 353, and the drive shaft 353 has a male threaded portion 35a formed approximately in the center thereof, and a sheath member 343 is threaded with a female threaded portion 34a3 so as to surround the male threaded portion 35a. It matches. The sheath member 343 is attached to the shake correction lens holding frame 9. A cover member 13. is fixedly attached to the tip of the cover member 13. Fixed. Further, the gear 363 is fitted to the top of the sheath member 343, and the gear 363 relative to the sheath member 343. can be rotated freely. Therefore, when the drive motor rotates, the interlocking lever 241, the gears 613 and 363, and the drive shaft 35. The rotation of the drive shaft 353 is transmitted to the sheath member 34. The movement in the axial direction occurs due to the screw engagement with the image stabilization lens frame 10. The position can be adjusted. Image stabilization lens frame lO3
is cover member 13. Inner flange portion 32. and an inner flange portion 333 formed at the tip of the blur correction lens holding frame 93. The shake correction lens frame 10° is
Although the first embodiment and the other embodiments are similar, they receive an urging force from the opposite side in the radial direction. Therefore, if the movement of the drive shaft 353 becomes high speed, there is a possibility that the movement of the lens frame lO3 will not be able to follow the movement. As a countermeasure, it is possible to reduce the weight of the shake correction lens frame 10° and the shake correction lens 113, and to increase the biasing force.
If the biasing force is increased, the load on the drive motor will increase, which is not preferable. Therefore, when trying to reduce the weight of lenses and lens frames, it is common practice to make them plastic, but there are concerns about their durability against sliding and impact. Therefore, in this embodiment, as shown in FIG. 7, by using steel balls 383 and metal sliding plates 39a3+39b3, it is possible to reduce the weight and improve durability. In addition, 3
7. is steel ball 38. It is a retainer. Especially the image stabilization lens frame 10. The structure on the side that biases and supports the sixth
As shown in the figure, the supporting portion of the lens frame IO5 has surfaces parallel to each of the X and Y directions, and the steel balls 143 are arranged along these surfaces as shown in FIG. 9.10. A roughly T-shaped biasing plate 22 for maintaining the state. A compression coil spring 233 is fitted to the vertical bar portion of the spring. In this embodiment, the lower end of the drive shaft 353 is formed into a spherical surface, but in order to further reduce the friction at that part, a steel ball 38°3 is also provided at the tip, as shown in FIG. It may be provided. In addition, in the third embodiment described above, the drive shaft 353 moves in the axial direction while rotating, but in the fourth embodiment, the structure shown in FIG. It is also possible to move it in the axial direction without moving it. Specifically, the cover member 13. A drive shaft 354 is connected to a sheath member 344 fixed to the sheath member 344, and the drive shaft 354 and the gear 364 are screwed together inside a helical gear 364. The helical gear 364 is rotatable relative to the sheath member 344. FIGS. 12 and 13 show a grooved cam type as a fifth embodiment of the shake correction drive mechanism. In this embodiment, the interlocking lever 24. A disk member having a spiral grooved cam 155 is attached to the tip. This grooved cam15. The cam profile consists of a spiral groove concentric with the rotation center of the interlocking lever 245, and the drive shaft 35 is used as a cam follower.
．． The tip of the cam is engaged with this cam groove. The other end of the drive shaft 35° is the vibration reduction lens frame 10. The intermediate portion thereof is in contact with the shake correction lens holding frame 9° or its cover member 13. Only axial movement is permitted and maintained through the . Therefore, the interlocking lever 24° and the disk member are rotated by the operation of the drive motor, and the spiral grooved cam 155 and the drive shaft 35. By engagement with the drive shaft 35. moves in the axial direction and the image stabilization lens frame 105
The position is adjusted. 14 and 15 show the sixth and seventh parts of the shake correction drive mechanism.
A ball screw type is shown as an example. This type has a sheath member 343 and a drive shaft 35 in the third embodiment. This can be achieved by using a ball screw to engage the helical gear 364 and the drive shaft 354 in the fourth embodiment. 168 and 16 in each figure. is a steel ball,
176 and 167 are spiral V-shaped grooves formed on the outer peripheral surface of the drive shaft; 18. and 187 is steel ball 1
6. ．． 7 into the V-shaped groove 17. , is a spring member that presses inward. In addition, with the ball screw type, there is no need to provide a slip structure to protect the mechanism when the drive range is pushed all the way to the end. In each of the above-mentioned embodiments, in order to disclose as many variations of each component as possible, some parts are shown differently for each embodiment. Of course, the combinations thereof may be changed.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the image stabilization lens barrel according to the present invention, and FIG. FIG. 3 is a schematic diagram showing the structure of the vicinity of the drive means of the shake correction drive mechanism in the shake correction lens barrel according to the present invention. FIG. 4 is a diagram illustrating the operating state of the position detection mechanism in the shake correction drive mechanism of FIG. 3. FIG. 5 is a longitudinal sectional view showing a multi-rotation cam type as a second embodiment of the shake correction drive mechanism. FIG. 6 is a front view showing a screw type as a third embodiment of the shake correction drive mechanism, FIG. 7 is a sectional view of the main part of the third embodiment,
FIG. 8 is a sectional view of a main part of a partial modification of the third embodiment of the image stabilization mechanism, and FIG. 9 is a longitudinal sectional view showing the steel ball structure on the side that urges and supports the image stabilization lens frame in the third embodiment. , FIG. 10 is a bottom view of FIG. 9. FIG. 11 is a sectional view of a main part showing another example of the screw type as the fourth embodiment of the shake correction mechanism. FIG. 12 is a diagram showing a grooved cam type spiral grooved cam as a fifth embodiment of the shake correction mechanism, and FIG. 13 is a schematic diagram showing the state of engagement between the grooved cam and the drive shaft of the fifth embodiment. FIG. 14 is a schematic diagram showing an example of a ball screw type as the sixth embodiment of the shake correction mechanism;
FIG. 5 is a schematic diagram showing another example of the ball screw type as the seventh embodiment of the shake correction mechanism. DESCRIPTION OF SYMBOLS 11... Shake correction lens, 9... Shake correction lens holding frame as a regulating means, ■3... Cover member as a regulating means, 21... Pressing bottle as a pressing means, 22
...Biasing plate as guide biasing means, 35... Drive shaft as pressing means

Claims (1)

[Claims] (1) A shake correction lens that can be adjusted and moved in a direction perpendicular to the optical axis of the photographic optical system to correct camera shake during shooting (
11), a regulating means (9, 13) for regulating the movement of the image stabilizing lens (11) between two opposing surfaces perpendicular to the optical axis direction; guide and urging means (22) that urges the vibration reduction lens (11) in at least two directions that intersect with each other on the axis and mutually guide the movement of the vibration reduction lens (11) due to the mutual urging; , are provided at respective positions facing the guide/biasing means (22), and the guide/biasing means (22)
2) A camera shake correction lens barrel comprising: pressing means (21, 35) for pushing and moving the shake correction lens (11) against the urging force of item 2).