Optical unit and endoscope
阅读说明:本技术 光学单元及内窥镜 (Optical unit and endoscope ) 是由 齐藤香那子 齐藤猛志 于 2017-06-13 设计创作,主要内容包括:光学单元(30)具备:移动框(35),其进退自如地配设在固定框(41)内,对移动透镜(33)进行保持;致动器,其沿着移动透镜的光轴(O)对移动框进行驱动;多个球体(61、62),它们能够使移动框滑动;多个引导槽(63、64),它们引导多个球体;多个磁铁(38a、38b、39a、39b),它们被配设为产生与摄影光轴正交的方向的磁力;以及磁性构件(51、51),其配设在与多个磁铁对置的位置,抵消通过磁力而在与多个磁铁之间产生的相反方向的引力(F1、F2),使移动框产生仅朝向将多个球体抵靠于引导槽的方向的作用力。(The optical unit (30) is provided with: a moving frame (35) which is disposed in the fixed frame (41) so as to be able to advance and retreat, and which holds the moving lens (33); an actuator that drives the moving frame along an optical axis (O) of the moving lens; a plurality of balls (61, 62) that can slide the moving frame; a plurality of guide grooves (63, 64) that guide the plurality of balls; a plurality of magnets (38a, 38b, 39a, 39b) arranged to generate magnetic force in a direction orthogonal to the photographing optical axis; and magnetic members (51, 51) disposed at positions facing the magnets, and configured to cancel attraction forces (F1, F2) in opposite directions generated between the magnets by magnetic force, thereby generating a biasing force in a direction in which the movable frame abuts the balls against the guide groove.)
1. An optical unit, characterized in that,
the optical unit includes:
a movable frame which is arranged in the fixed frame to be freely advanced and retreated and holds the movable lens;
an actuator that drives the moving frame along an optical axis of the moving lens;
a plurality of spheres that enable the moving frame to slide relative to the fixed frame in a direction along the photographing optical axis;
a plurality of guide grooves that guide sliding of the plurality of balls along the photographing optical axis;
a plurality of magnets arranged to generate a magnetic force in a direction orthogonal to the photographing optical axis; and
and a magnetic member disposed at a position facing the plurality of magnets, and configured to generate a biasing force in a direction to urge the plurality of balls against the guide groove, by canceling an attraction force in a direction opposite to the direction generated between the plurality of magnets by the magnetic force.
2. An optical unit according to claim 1,
the plurality of magnets are disposed at point-symmetrical positions of the moving frame with the photographing optical axis as a center.
3. An optical unit according to claim 1 or 2,
the plate-shaped magnets and the magnetic members are arranged so as to face each other such that the facing planes thereof are parallel to a plane passing through the centers of the spherical bodies.
4. An optical unit according to any one of claims 1 to 3,
the plurality of guide grooves are arranged with the optical axis as a boundary.
5. An optical unit according to any one of claims 1 to 4,
the actuator is a voice coil motor having the plurality of magnets and a plurality of coils.
6. An optical unit according to any one of claims 1 to 5,
an imaging element is provided on the fixed frame on the base end side of the movable frame.
7. An endoscope, characterized in that,
the optical unit according to any one of claims 1 to 6 is disposed at a distal end portion of the insertion portion.
Technical Field
The present invention relates to an optical unit including a movable lens frame and an endoscope including the optical unit.
Background
In recent years, endoscopes that can observe a region to be examined that cannot be directly visualized by inserting an elongated insertion portion into a body cavity or the like have been widely used. Among such endoscopes, an electronic endoscope provided with an imaging device as an optical unit is known.
In an imaging device such as a camera having a zoom function and a focus function, a structure is known in which a guide shaft and a sleeve that linearly guide a moving lens frame holding a moving lens slide.
In this way, in the case of using the guide shaft, the sleeve, or the like, the friction coefficient of sliding friction is high, and therefore grease or oil is used to suppress the friction coefficient. Further, in the case where the driving force of an actuator for driving a moving lens frame used in a digital single-lens reflex camera or the like is large, even if oil or grease which generates viscous resistance is used, there is no problem.
However, in a particularly small imaging device mounted on a mobile phone, an endoscope, or the like, since an actuator for driving a movable lens frame is also small, it is necessary to be able to drive the movable lens frame even with a small driving force generated by the actuator.
Therefore, when the imaging device is configured using the guide shaft and the sleeve, there is a problem in that viscous resistance due to grease or oil is generated with respect to a small driving force of the actuator. Therefore, it is difficult to miniaturize an imaging device having a movable lens frame using a shaft and a sleeve, and it is difficult to apply the imaging device to a mobile phone and an endoscope.
In contrast, for example, the invention of an imaging device including an optical unit that employs ball sliding based on rolling friction so that a moving lens frame can be driven even by the driving force of a small actuator has been proposed in japanese patent application laid-open No. 8-29656 or japanese patent application laid-open No. 2008-40188.
However, in the conventional imaging device, a biasing member such as a plate spring disclosed in japanese patent application laid-open No. 8-29656 biases the lens frame so as to slide and support the lens frame toward the balls, and a space for disposing the biasing member is required. Therefore, the conventional imaging apparatus has a problem that further miniaturization is difficult.
Further, the imaging device of jp 2008-40188 a has a structure in which the movable lens is attracted to the ball sliding side by the magnetic force of the magnet.
Further, the conventional imaging apparatus disclosed in japanese patent application laid-open No. 8-29656 or 2008-40188 also has a problem that it is very difficult to set the following settings without increasing the size: the moving lens frame is smoothly driven without loss by adjusting the urging force generated by the urging member sliding toward the balls or the attraction force generated by the magnet with a small driving force of the actuator.
In view of the above, it is an object of the present invention to provide a small-sized optical unit having a zoom function and a focus function, which can smoothly slide a movable lens frame without increasing the size of the optical unit, and an endoscope including the optical unit.
Disclosure of Invention
Means for solving the problems
An optical unit according to an aspect of the present invention includes: a movable frame which is arranged in the fixed frame to be freely advanced and retreated and holds the movable lens; an actuator that drives the moving frame along an optical axis of the moving lens; a plurality of balls that enable the moving frame to slide relative to the fixed frame in a direction along the optical axis; a plurality of guide grooves that guide sliding of the plurality of balls along the optical axis; a plurality of magnets arranged to generate a magnetic force in a direction orthogonal to the optical axis; and a magnetic member disposed at a position facing the plurality of magnets, and configured to generate a biasing force in a direction to urge the plurality of balls against the guide groove by the moving frame by canceling an attraction force in a direction opposite to the direction generated between the plurality of magnets by the magnetic force.
An endoscope according to an aspect of the present invention includes an optical unit disposed at a distal end portion of an insertion portion, the optical unit including: a movable frame which is arranged in the fixed frame to be freely advanced and retreated and holds the movable lens; an actuator that drives the moving frame along an optical axis of the moving lens; a plurality of balls that enable the moving frame to slide relative to the fixed frame in a direction along the optical axis; a plurality of guide grooves that guide sliding of the plurality of balls along the optical axis; a plurality of magnets arranged to generate a magnetic force in a direction orthogonal to the optical axis; and a magnetic member disposed at a position facing the plurality of magnets, and configured to cancel 2 attractive forces in opposite directions generated between the magnetic member and the plurality of magnets by the magnetic force, and generate an urging force of the moving frame only in a direction of abutting the ball against the guide groove.
Drawings
Fig. 1 is a perspective view showing the structure of an endoscope.
Fig. 2 is a schematic view showing a front end portion of the insertion portion.
Fig. 3 is a sectional view showing the structure of the moving lens unit in the fixed frame.
Fig. 4 is a sectional view showing the structure of the moving lens unit inside the fixed frame taken along the line IV-IV of fig. 3.
Fig. 5 is a sectional view showing the structure of the moving lens unit inside the fixed frame taken along the line V-V of fig. 3.
Fig. 6 is a sectional view corresponding to the line IV-IV of fig. 3 and showing a state where the moving lens unit in the fixed frame is moved to the base end side.
Fig. 7 is a sectional view corresponding to the V-V line of fig. 3 and showing a state where the movable lens unit in the fixed frame is moved to the base end side.
Fig. 8 is a partial sectional view for explaining a state where the moving lens unit is pulled to the ball sliding side.
Fig. 9 is a cross-sectional view of the moving lens unit for explaining the arrangement state of the components sliding on the balls.
Fig. 10 is a vertical cross-sectional view of the moving lens unit illustrating the arrangement state of the components for sliding the balls.
Fig. 11 is a cross-sectional view of the moving lens unit illustrating an example of the arrangement of the permanent magnet and the ferromagnetic body.
Fig. 12 is a cross-sectional view of the moving lens unit illustrating another example of the arrangement of the permanent magnet and the ferromagnetic body.
Fig. 13 is a plan view illustrating another example of the arrangement of the permanent magnet and the ferromagnetic body.
Fig. 14 is a sectional view showing the structure of the moving lens unit of modification 1.
Fig. 15 is a sectional view showing the structure of the moving lens unit of
Fig. 16 is a sectional view showing the structure of the moving lens unit of
Fig. 17 is a sectional view showing the structure of a moving lens unit of modification 4.
Detailed Description
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Fig. 1 is a perspective view showing a structure of an endoscope, fig. 2 is a schematic view showing a distal end portion of an insertion portion, fig. 3 is a sectional view showing a structure of a moving lens unit in a fixed frame, fig. 4 is a sectional view showing a structure of a moving lens unit in a fixed frame cut along a line IV-IV of fig. 3, fig. 5 is a sectional view showing a structure of a moving lens unit in a fixed frame cut along a line V-V of fig. 3, fig. 6 is a sectional view corresponding to a line IV-IV of fig. 3 and showing a state where the moving lens unit in the fixed frame moves to a base end side, fig. 7 is a sectional view corresponding to a line V-V of fig. 3 and showing a state where the moving lens unit in the fixed frame moves to the base end side, fig. 8 is a partial sectional view for explaining a state where the moving lens unit is pulled to a ball sliding side, and fig. 9 is a transverse sectional view for explaining a disposition state of constituent elements for ball sliding, fig. 10 is a vertical sectional view of the moving lens unit for explaining the arrangement state of the components sliding on the balls, fig. 11 is a sectional view of the moving lens unit for explaining one example of the arrangement of the permanent magnet and the ferromagnetic body, fig. 12 is a sectional view of the moving lens unit for explaining another example of the arrangement of the permanent magnet and the ferromagnetic body, and fig. 13 is a plan view for explaining another example of the arrangement of the permanent magnet and the ferromagnetic body.
In the drawings used in the following description, the components are sized to be recognizable on the drawings, and therefore the proportions may be different for each component. The present invention is not limited to the number of components, the shapes of the components, the ratios of the sizes of the components, and the relative positional relationships of the components shown in the drawings.
As shown in fig. 1, the endoscope 1 is mainly configured to include an
In the endoscope 1, the
The
The
Next, an
As shown in fig. 2, the
The
The
Then, the image pickup signal photoelectrically converted by the
The
As shown in fig. 3 to 7, the moving
The
The fixed
As described above, the moving
The moving
Of the 4
The 2 coils 45 and 46 are wound around an axis orthogonal to the photographing optical axis O, are electrically connected to the cable lines in the
In this way, the voice coil motor (hereinafter referred to as VCM) is configured by the total of 4
The
Specifically, a total of 4 balls made of metal, ceramic, or the like, that is,
The
The 2
The moving
That is, guide
Further, the
In this way, the balls rotating along the
During this forward and backward movement, the proximal end surface of the
Further, a position detection sensor 57 (see fig. 4 to 7) such as a hall element for detecting the forward/backward movement position of the
Here, the moving
Specifically, as shown in fig. 8, the moving
Further, in the moving
The 1 st attractive force F1 is set to be larger than the 2 nd attractive force F2(F1 > F2), and the 1 st attractive force F1 is canceled and relaxed by the magnetic 2 nd attractive force F2 generated by the moving
That is, the
The
That is, the opposing flat surfaces B, C of the
Accordingly, the 1 st attractive force F1 and the 2 nd attractive force F2 become attractive forces in a direction perpendicular to the plane a passing through the centers of the 4
In addition, various structures are considered for the structure for making the above-described 1 st attractive force F1 larger than the 2 nd attractive force F2(F1 > F2).
As an example, as shown in fig. 11, for example, if the spacing distance L2 is made larger than the spacing distance L1 (L1 < L2), the 1 st attractive force F1 can be larger than the 2 nd attractive force F2(F1 > F2), the spacing distance L2 being the distance between the
As another example, as shown in fig. 12, for example, if the thickness d1 of the
As another example, as shown in fig. 13, for example, if the surface area of the
Although not shown, the surface area of the
As described above, the
Therefore, the
(modification 1)
Fig. 14 is a sectional view showing the structure of the moving lens unit of modification 1.
As shown in fig. 14, the
In such a configuration,
That is, the
(modification 2)
Fig. 15 is a sectional view showing the structure of the moving lens unit of
As shown in fig. 15, the
(modification 3)
Fig. 16 is a sectional view showing the structure of the moving lens unit of
As shown in fig. 16, the
(modification 4)
Fig. 17 is a sectional view showing the structure of a moving lens unit of modification 4.
As shown in fig. 17, the
In the
The invention described in the above embodiments is not limited to the above embodiments, and various modifications can be made in other embodiments without departing from the scope of the invention. The above embodiments include inventions at various stages, and various inventions can be extracted by appropriate combinations of a plurality of disclosed constituent elements.
For example, in the case where the above-described problems can be solved and the above-described effects can be obtained even if several constituent elements are deleted from all the constituent elements shown in the embodiments, a configuration in which the constituent elements are deleted can be extracted as an invention.
- 上一篇:一种医用注射器针头装配设备
- 下一篇:准直器设备、照明设备、灯和照明器