JPH0384508A - Blurring correcting lens barrel - Google Patents

Abstract

PURPOSE:To use a light material such as a plastic material for a driving mechanism for a correcting lens and to prevent correcting operation from decreasing in accuracy by providing wear-resisting sliding means between at least one of a control means, a guide energizing means, and a pressing means and a frame body. CONSTITUTION:The frame body, control means, guide energizing means, and pressing means are made of light materials and the driving force which is required to move them is reduced as much as possible. Then the wear-resisting sliding means 38 and 39 are provided for the relation of contact with the frame body to compensate deterioration due to wear pertaining to the light materials and reduce the slide resistance. Consequently, the driving load is reduced by the weight reduction and the correction accuracy is improved and maintained.

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 well-known camera lens barrel is one in which some of the lenses that make up the photographic lens are used as shake correction lenses, and by moving this lens in a direction perpendicular to the optical axis, image shake can be corrected and blur can be suppressed. ing. Generally, in a shake correction lens barrel, when performing zooming or focusing, for example, it is necessary to move the correction lens in the optical axis direction.
The fact that the movement of the correction lens associated with zooming and focusing is performed with a small driving load reduces the feeling of operation. To this end, it is possible to reduce the weight of each component of the correction lens and its movement mechanism.
The most common method is to use plastic for each constituent material. However, plastic materials do not have sufficient wear resistance, and especially in those that include mechanical parts that repeatedly slide at high speed, such as the drive means of image stabilization lenses, the accuracy of lens correction operations may deteriorate due to wear. This will occur.

[Problem to be solved by the invention]

The present invention has been devised in view of the technical problems related to the drive mechanism of the shake correction lens as described above, and to effectively solve the problems. Therefore, an object of the present invention is to make it possible to use lightweight materials such as plastic materials for the drive mechanism of the compensation lens when making the drive mechanism lighter in order to make the motion compensation lens drive mechanism more compact and to improve the followability of the motion compensation lens. It is an object of the present invention to provide a camera shake correction lens barrel which can solve problems related to wear resistance and prevent a decrease in accuracy of lens correction 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 camera 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 camera shake correction lens is held and moved for adjustment. a frame body receiving a driving force; a regulating means for regulating the movement of the frame body between two opposing surfaces perpendicular to the optical axis direction; and at least two directions toward the optical axis and intersecting each other at the optical axis - a guide and bias means for biasing the frame and mutually guiding movement of the frame due to mutual bias; and a guide and bias means provided at respective positions opposite to the guide and bias means; a suppressing means for pushing and moving the frame body against the urging force of the frame body, at least one of the frame body, the regulating means, the guiding urging means, and the pressing means is made of a lightweight material, and the regulating means, A wear-resistant sliding means is provided between at least one of the guide biasing means and the pressing means and the frame.

[Action and effect of the invention]

In the image stabilization lens barrel according to the present invention, the image stabilization lens is held by the frame, and a driving force acts on the frame to drive the image blur correction lens. During this adjustment movement, the direction of movement of the frame is regulated between two opposing surfaces, and since the two opposing surfaces are perpendicular to the optical axis, the image stabilization lens is adjusted while always maintaining an attitude perpendicular to the optical axis. Make a move. Furthermore, this adjustment movement is
This is caused by the difference between the urging force of the guide and urging means and the pressing force of the suppressing means, and the guiding and urging means form a pair whose urging forces intersect on the optical axis, and the pressing means also faces the pair. Since the pressing forces that intersect on the optical axis are applied to the blurring correction lens, the blurring correction lens can be positioned using these two components in different directions. When moving this image stabilizing lens, at least one of the frame, the regulating means, the guiding and urging means, and the pressing means are preferably all made of lightweight material, so that the driving force required for the movement is The force can be reduced as much as possible. Preferably, all of them are provided between the frame and at least one of the following regulating means, guiding biasing means, and pressing means that guide and regulate the adjustment movement of the image stabilization lens in contact with the frame. By providing a wear-resistant sliding means between the lever and the frame, a reduction in sliding resistance can be achieved while compensating for the poor wear resistance of the materials typically associated with the lightweight materials mentioned above. Therefore, according to the present invention, it is possible to reduce the driving load due to the above-mentioned weight reduction, and at the same time, it is possible to improve and maintain correction accuracy.

【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 first and fourth group moving frames 7 are disposed on the inner circumferential side of the fixed cylinder 2.
A guide pin 45 is disposed on the outer peripheral surface of the movable frame 7 and protrudes outward in the radial direction, penetrates the straight groove 2a of the fixed barrel 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, 46 is a guide pin that projects from the second group moving frame 8 and engages with the cam groove 6b, and 47 is a shake correction This is a guide pin that projects from the lens holding frame 9 and engages with the cam groove 6c. As each moving frame 7, 8 and holding frame 9 move in a straight line, a drive lever 20 (see FIG. 2) and an interlocking lever 24, which will be described later, remain integral in the rotational direction and are guided by the long groove 20a to guide the optical axis. The correction lens holding frame 9 is slid in the optical axis direction without interfering with the 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 circumferential 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 1o 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. FIG. 2 is a diagram showing the relationship between the blurring correction lens 11, the blurring correction lens holding frame 9, the blurring correction lens frame 10, and other peripheral mechanisms shown in FIG. 1, as viewed from the object side. The lens frame 10 has press bottles 21x and 21y (X
(The correction mechanism in the direction is indicated by adding X to the reference number, and the correction mechanism in the X direction is indicated by adding y to the reference number) and biasing 122x,
22y are provided in contact with each other, and biasing plates 22x, 22
y, each head is moved in the X direction and
It is pressed so as to be biased in the direction. On the other hand, press bottle 21X. The tip of the lens 21y is pressed in a direction opposite to the biasing direction of the leaf spring 23 by the drive levers 20x and 20y, thereby positioning the lens frame 1o. In FIG. 3, a drive motor 29, an interlocking gear 25
, 26, 27, a light shielding plate 3o, and a photoink clubter 31 are shown as one set, and 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. The interlocking lever 24 has a length t relative to the drive lever 2° held by the shake correction lens holding frame 9.
Since they are engaged at c20a, the drive lever 20 also rotates as the interlocking lever 24 rotates, and the press bottle 21 is pushed in. For example, when the press bottle 21K in the X direction is pushed in, the image stabilization lens frame IO
It moves in the X direction against the urging force of 3. At this time, regarding the press bottle 21y and the biasing plate 22y in the X direction, the contact surface of the shake correction lens frame 10, which the press bottle 21y and the bias 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 20 also rotate in the reverse direction, and the blur correction lens frame 10 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 driving force transmission mechanism can be constantly absorbed, and there is no "play" in the correction operation of the shake correction lens frame 10 that follows the movement of the drive mechanism. , the accuracy of its operation can be increased. 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, and 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. By rotating in synchronization with the gear 25, the light shielding plate 30 allows the light of the photo ink converter 31 to pass through and obtains its output only when the shake correction lens frame 10 is at the center of the optical axis. It has a slit. Therefore, by rotating the pulse motor 29 in the reverse direction after driving the vibration reduction lens frame 10 and stopping the pulse motor 29 at the position where the output of the photo interrupter 31 is, the vibration reduction lens frame 10 is moved to the initial position where the correction amount is 0. can be restored to. Figure 4a shows photo interrupter 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, and the image stabilization lens holding frame 9. The other end is the image stabilizing 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 vibration reduction lens holding frame 9. Female screw 12 formed at the tip of
．． By screwing into the drive cam 20t, the drive cam 20t moves in the optical axis direction as the interlocking lever 24 degrees rotates, 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. Incidentally, the pitch of the rotor 20a is the same as the pitch of the spiral of 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
43, a helical gear 613 is connected in an oval manner. A helical gear 363 that changes the direction of rotation by 90 degrees is screwed into the gear 613. The direction of the rotation axis of the gear 363 is perpendicular to the optical axis of the photographic optical system. A drive shaft 353 is coupled to the gear 363, and the drive shaft 35. A male screw portion 35a3 is formed approximately in the center of the sheath member 343, which is screwed to the female screw portion 34a so as to surround the male screw portion 35a3. The sheath member 343 is fixed to a cover member 133 fixedly attached to the tip of the shake correction lens holding frame 93. Further, the gear 363 is connected to the sheath member 34. The gear 36. is fitted onto the top of the sheath member 343. can be rotated freely. Therefore, when the drive motor rotates, the rotation is transmitted to the interlocking lever 243, the gears 613 and 363, and the drive shaft 353, and the rotation of the drive shaft 353 causes movement in the axial direction from the threaded engagement with the sheath member 343, resulting in blurring. Correction lens frame 10. The position can be adjusted. Shake correction lens frame 103
is cover member 13. and the inner flange portion 323 of the shake correction lens holding frame 9. The inner flange portion 33 formed at the tip of the inner flange portion 33 is sandwiched between the inner flange portion 33 formed at the tip portion of the inner flange portion 33 . 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 103 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 TT, 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 customary to make them plastic, but there are concerns about their durability against sliding and impact. Therefore, in this embodiment, as shown in FIG. 7, steel balls 38. By using the metal sliding plates 39 as and 39 ha, it is possible to reduce the weight and improve the cutting property. Furthermore, 37
．． is a retainer for steel balls 383. Particularly, the structure of the side that biases and supports the image stabilizing lens frame 108 is as shown in FIG. in the X direction and
forming planes parallel to each of the directions, along which the steel balls 14. A roughly T-shaped biasing plate 223 is used to hold the 23. It is constructed by fitting. 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 its tip, as shown in FIG. It may be provided. Further, in the third embodiment described above, the drive shaft 35. The drive shaft 354 moves in the axial direction while rotating, but by adopting a structure as shown in FIG. 11 as a fourth embodiment, it is also possible to move the drive shaft 354 in the axial direction without rotating it in the screw type. be. 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. The cam profile of this grooved cam 156 consists of a spiral groove concentric with the rotation center of the interlocking lever 245, and serves as a cam follower for the drive shaft 35.
．． The tip of the cam is engaged with this cam groove. The other end of the drive shaft 35° is in contact with the image stabilization lens frame IO6, and the intermediate portion thereof is in contact with the image stabilization lens holding frame 95 or its cover member 13. Only axial movement is permitted and maintained through the . , Therefore, the interlocking lever 245 and the disc member are rotated by the operation of the drive motor,
Spiral groove cam15. and the drive shaft 355, the drive shaft 35. moves in the axial direction and the image stabilization lens frame 10
．． 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 is obtained by configuring the threaded engagement between the sheath member 343 and the drive shaft 353 in the third embodiment using a ball screw, and the threaded engagement between the helical gear 364 and the drive shaft 354 in the fourth embodiment. This can be obtained by constructing the ball screw. 16° and 16. 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. , , into the V-shaped groove 17°, 7. Note that 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. 9... Shake correction lens holding frame as a regulating means, 10
... Shake correction lens frame as a pair of frames, 11... Shake correction lens, 13... Cover member as a regulating means,
21... Pressing bottle as pressing means, 22... Biasing plate as guiding and urging means, 35... Drive shaft as pressing means, 14.38... Steel as wear-resistant sliding means Ball, 39... Sliding plate as wear-resistant sliding means Fig. 2 22y 3 Fig. 3 Fig. 4 ov! J Fig. 4b Fig. 7 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. f 4 Q Fig. 13

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), between a frame (10) that holds the image stabilization lens (11) and receives a driving force for the adjustment movement, and two opposing surfaces perpendicular to the optical axis direction. regulating means (9,
13) and biasing the frame (10) in at least two directions that face the optical axis and intersect with each other on the optical axis, and mutually guide the movement of the frame (10) due to the mutual biasing. and a guide biasing means (22) provided at respective positions facing the guide biasing means (22) to push the frame (10) against the biasing force of the guide biasing means (22). Pressing means (21,
35), at least one of the frame body (10), the regulating means (9, 13), the guide biasing means (22) and the pressing means (21, 35) is made of a lightweight material, and the regulating means (9, 13) is made of lightweight material; Wear-resistant sliding means (14,
38, 39).