JP7255221B2 - STAGE MECHANISM AND IMAGING DEVICE INCLUDING THE SAME - Google Patents

Description

The present invention relates to a stage mechanism that moves an object in a predetermined direction.

In a stage mechanism, an object can be freely moved, for example, in two directions perpendicular to each other. A stage mechanism for moving is provided.

In the stage mechanism, in order to accurately move the object, a guide means is required which realizes smooth planar motion of the moving body without causing backlash along the moving direction and its vertical direction. As the guide means, a configuration is known in which a spherical body (rolling body) holds the moving body (see, for example, Patent Document 1).

On the other hand, for the purpose of reducing the size and weight of the stage mechanism, the support body made of a thin steel plate with high rigidity is processed into a U-shape, and the stage is bent into a U-shape, and a track is provided between them. A configuration is known in which a stage is slid by sandwiching a sphere in a groove (see Patent Document 2).

Japanese Patent Application Laid-Open No. 2007-310289 JP-A-5-18415

Conventional stage mechanisms require materials with high rigidity and processing technology, and in some cases, complicated component shapes and complicated adjustment processes after assembly.

Therefore, there is a demand for a stage mechanism that is configured with simple member shapes without restrictions on the materials used and that is easy to adjust after assembly.

The stage mechanism of the present invention includes a set of support plates parallel to each other, and at least one stage plate supported by the set of support plates via a sphere and movable in a predetermined direction along the set of support plates. A pressurization adjustment mechanism that applies pressurization to the sphere that is in contact with one of the support plates is provided. Between a set of support plates sandwiching the stage plate, multiple spheres are arranged along the direction perpendicular to the direction of movement of the stage plate, and the pressurization adjustment mechanism can apply pressurization according to the amount of screwing. is. The stage mechanism of the present invention can be incorporated into an imaging device.

A method for supporting a stage mechanism, which is one aspect of the present invention, includes a set of support plates parallel to each other, and a sphere so that at least one stage plate can be moved in a predetermined direction along the set of support plates. A stage mechanism support method for applying pressure to a sphere in contact with one of the support plates by means of a pressure adjustment mechanism capable of applying a pressure corresponding to the amount of screwing, the method comprising: A stage mechanism characterized by arranging a plurality of spheres between a set of sandwiched support plates along a direction perpendicular to the direction of movement of the stage plate, and applying a pressure corresponding to a screwing amount set in the pressure adjustment mechanism. support method.

According to the present invention, it is possible to configure a stage mechanism that is configured with simple member shapes without any restrictions on the materials used, and that can be easily adjusted after assembly.

1 is a schematic perspective view of an imaging device according to this embodiment; FIG. 3 is an exploded perspective view of a stage mechanism that constitutes the sensor shift mechanism; FIG. FIG. 2B is an exploded perspective view of the stage mechanism viewed from an angle different from that of FIG. 2A; It is a front view of a stage mechanism. It is a rear view of a stage mechanism. It is a side view of a stage mechanism. FIG. 4 is a diagram showing elements related to movement of the X stage plate and the Y stage plate; 4 is a cross-sectional view of the stage mechanism along S1-S1 in FIG. 3; FIG. FIG. 8 is a cross-sectional view enlarging a part of FIG. 7; FIG. 9 is a cross-sectional view showing a modified example of this embodiment. FIG. 10 is a sectional view and a perspective view showing a modified example of this embodiment.

An imaging apparatus according to the present embodiment will be described below with reference to the drawings.

FIG. 1 is a schematic perspective view of an imaging apparatus according to this embodiment.

An imaging device 100 such as a digital camera includes a lens barrel 110 and a sensor shift mechanism 120 . The sensor shift mechanism 120 shifts an image sensor, which will be described later, in the X and Y directions so as to cancel camera shake during shooting. Note that the image sensor may be shifted for the purpose of removing color moire. Hereinafter, the horizontal direction of a plane orthogonal to the optical axis of the photographing lens accommodated in the lens barrel 110 is defined as the X direction, the vertical direction is defined as the Y direction, and the direction parallel to the optical axis is defined as the Z direction.

FIG. 2A is an exploded perspective view of a stage mechanism that constitutes the sensor shift mechanism 120. FIG. FIG. 2B is an exploded perspective view of the stage mechanism seen from a different angle than in FIG. 2A. 3, 4 and 5 respectively show a front view, rear view and side view of the stage mechanism. However, the front view is the view seen from the image sensor side.

The stage mechanism 10 includes a pair of support plates 20 and 30 and two stage plates 40 and 50 (hereinafter referred to as an X stage plate and a Y stage plate) sandwiched between them. are assembled and integrated (see FIGS. 2A, 2B and 5). An object to be driven can be fixed to the Y stage plate 50 by supports 58A to 58D. Here, the sensor support plate 90 holding the image sensor 90A in the center is fixed to the Y stage plate 50 with the support plate 30 therebetween (see FIGS. 2B, 5, etc.).

The support plate 20 and the support plate 30 are fixed by support columns 24A to 24D (see FIG. 2B) near the four corners of the support plate 20 and screws 30A to 30D (see FIG. 2A) near the four corners of the support plate 30. there is The support plate 20 and the support plate 30 are parallel to each other in the X direction and are spaced apart from each other. The support plate 20 includes an X stage actuator 26 and a pair of guide rollers 28 (see FIG. 2B, etc.), and moves the facing X stage plate 40 along the X direction (horizontal direction).

A stepped portion 40T is formed near two lower corners of the X stage plate 40, and a pair of guide rollers 28 provided on the support plate 20 are in contact with the stepped portion 40T. A pair of movement guide springs 45 provided near the two lower corners of the X stage plate 40 are attached to the support columns 24C and 24D of the support plate 20 and press the X stage plate 40 against the pair of guide rollers 28. FIG. This allows the X stage plate 40 to move only in the X direction.

The X stage actuator 26 provided on the support plate 20 is composed of, for example, a piezo actuator or the like, and expands and contracts according to the applied voltage. A pair of stage restoration springs 48 provided on the X stage plate 40 urges the X stage plate 40 in a direction to contact the X stage actuator 26 , and the X stage plate 40 moves in the X direction according to the expansion and contraction of the X stage actuator 26 . move in the direction

A pair of guide rollers 47 are provided on the X stage plate 40 along the Y direction (see FIGS. 2B and 3). The pair of guide rollers 47 are in contact with the edges of the pair of openings 50T provided in the Y stage plate 50 . A pair of movement guide springs 54 provided on the Y stage plate 50 are attached to the supports 49 of the X stage plate 40 (see FIGS. 2A and 3), and the Y stage plate 50 is pressed against a pair of guide rollers 47. FIG. This allows the Y stage plate 50 to move only along the Y direction.

A Y stage actuator 46 is provided on the X stage plate 40, and a pair of stage restoration springs 56 are provided on the Y stage plate 50 (see FIGS. 2A, 2B, etc.). The Y stage actuator 46 can also be composed of a piezo actuator or the like, and the Y stage plate 50 moves in the Y direction as the Y stage actuator 46 expands and contracts.

Thus, the Y stage plate 50 can move relative to the X stage plate 40 only in the Y direction, but the X stage plate 40 can move in the X direction with respect to the support plate 20 as described above. Therefore, the Y stage plate 50 to which the image sensor 90A is fixed is movable in the X and Y directions, and is guided by the pair of guide rollers 28 and 47 in the movement direction. FIG. 6 is a diagram showing elements related to movement of the X stage plate 40 and the Y stage plate 50. As shown in FIG.

On the other hand, for the guides of the X stage plate 40 and the Y stage plate 50 in the direction perpendicular to the direction of stage movement, spheres are used as will be described later. 50. The spheres are arranged so that there is no backlash along the direction perpendicular to the stage moving surface (optical axis direction), that is, the X stage is arranged so as to maintain the parallel relationship between the X stage plate 40, the Y stage plate 50, and the support plates 20, 30. It guides the plate 40 and the Y stage plate 50 . This will be explained in detail below.

FIG. 7 is a cross-sectional view of the stage mechanism along S1-S1 in FIG. FIG. 8 is a cross-sectional view enlarging the range of symbol K in FIG.

As shown in FIG. 2A, the support plate 20 is provided with three retainers 22A to 22C for pressurization adjustment, which will be described later, near the two upper corners and the center of the lower end. Three spheres are arranged between the support plate 20 and the support plate 30 from the retainers 22A to 22C along the Z direction, that is, the direction perpendicular to the direction of stage movement.

FIG. 8 shows spheres 80A to 80C aligned in the Z direction at the retainer 22A. However, it shows the arrangement when the stage drive is OFF. The sphere 80A is configured as a guide for integrally maintaining the distance between the support plate 20 and the X stage plate 40, and is housed in a retainer 22A attached to the support plate 20. FIG.

The sphere 80B enters a through-hole corresponding to the diameter of the sphere 80B provided in the Y stage plate 50, and keeps the distance between the Y stage plate 50 and the X stage plate 40 constant. The sphere 80C enters a through-hole corresponding to the diameter of the sphere 80C provided in the support plate 30, and keeps the distance between the Y stage plate 40 and the support plate 30 constant. The spheres 80A to 80C slide in the holes held rotatably when the X stage plate 40 and the Y stage plate 50 move at the positions where they are held. Also, the sphere 80B held by the Y stage plate 50 moves relative to the X stage plate 40. FIG.

The Y stage plate 50 and the support plate 30 are provided with plates (hereinafter referred to as slide plates) 52A and 32A that also serve as ball receivers and ball sliding surfaces, respectively, and are screwed (FIGS. 2A, 2B, and 8). reference). On the other hand, even for the X stage plate 40 which is not provided with holes for holding the spheres such as through holes, a sliding plate 42A which contacts the spheres 80A and a slide plate 42A which contacts the spheres 80B are provided on the support plate 20A side surface and its back side surface. 44 A of moving plates are each attached. The sliding plates 42A and 44A are made of a hard material having hardness greater than that of the X stage plate 40 and Y stage plate 50. As shown in FIG. The other sliding plates 32A, 52A may also be made of a similar hard material.

The retainers 22B and 22C also have a configuration in which three spherical bodies are similarly arranged along the direction perpendicular to the direction of stage movement. As a result, the distance between the support plate 20 and the X stage plate 40, the distance between the X stage plate 40 and the Y stage plate 50, and the distance between the Y stage plate 50 and the support plate 30 are maintained constant over the entire plate. The stage plate 40 and the Y stage plate 50 can move in the X and Y directions without rattling.

The positions of the spheres corresponding to the positions of the retainers 22A, 22B, and 22C are determined to be evenly spaced from each other so as to achieve smooth planar motion of the X stage plate 40 and Y stage plate 50. FIG. Although the spheres are aligned at three locations here, the configuration may be such that the spheres are aligned at four or more locations.

In this embodiment, the stage plate is composed of the X stage plate 40 and the Y stage plate 50, and all the spheres, including the sphere 80B that relatively moves with the movement of the Y stage plate 50, face each other in the same direction. Lined up. As a result, warping deformation of the X stage plate 40 and the Y stage plate 50 due to pressurization is suppressed, the rigidity of the stage material is not required more than necessary, and the stage can be thinned with a simple shape.

For example, when the stage dimensions are about 100 m×100 mm, the X stage plate 40 and the Y stage plate 50 can be constructed from aluminum with a thickness of 1 mm or less. If it is made of a material such as stainless steel, it can be made even thinner. For example, it is possible to configure a larger number of stage plates so as to move in the X and Y directions perpendicular to each other.

Furthermore, by providing the sliding plates 42A and 44A on the surface of the X stage plate 40 that is not provided with the spherical body holding holes, the X stage plate 40 can be prevented from receiving a point load from the spherical body. The board material can be freely selected. For example, the X stage plate 40 can be molded with a soft material such as resin.

By the way, depending on the mounting posture of the stage mechanism 10, there is a possibility that the parallel distance between the support plates 20 and 30 and the X stage plate 40 and the Y stage plate 50 will be disturbed due to the weighted load of the sensor support plate 90 that is to be driven. There is, and it is necessary to give appropriate pressurization to the sphere.

In this embodiment, pressurization adjusting mechanisms 21A-21C are provided at locations where retainers 22A-22C are attached. As shown in FIG. 8, the pressurization adjustment mechanism 21A includes a retainer 22A, a sphere 80A that is in contact with the support plate 20 and applies pressurization, a pressurization piece 23A, a spring 25A, and a screw (here, referred to as a pressurization adjustment screw). 27A. Other pressurization adjusting mechanisms 21B and 21C are similarly configured.

The pressurization adjustment screw 27A is configured as a hollow screw that can be screwed into the retainer 21A, and the pressurization piece 23A is configured as an urging member that transmits the force of the spring 25A to the spherical body 80A. The pressurized load is obtained from the deflection load of the spring 25A, and this deflection load can be estimated from the specifications including the wire diameter and free height of the spring 25A and the deflection amount of the spring 25A.

Since the amount of deflection of the spring 25A is determined by the pitch of the pressurization adjustment screw 27A and the screwing speed, the pressurized load can be set by determining the screwing speed. That is, by adjusting the screw-in rotation speed (the amount of screw-in) to a rotation speed according to the desired pressurization, it is possible to easily adjust the pressurization without using a dedicated measuring instrument or the like even after assembly.

Although the configuration in which the sliding plates are attached to both sides of the X stage plate 40 has been described, if the X stage plate 40 and the Y stage plate 50 are molded from a hard material, such sliding plates may not be provided. . FIG. 9 shows an example of such a configuration. There, only the sliding plate 52 is provided.

Alternatively, the X-stage plate 40 may be provided with a ball-holding hole so that the ball can be inserted therein, and the Y-stage plate 50 may not be provided with a ball-holding hole. FIG. 10 shows an example of such a configuration. Sliding plates 52A and 52A' are placed on both sides of the Y stage plate 50 there. Further, a guide groove GG is formed along the X direction in the sliding plate 42A. The guide groove GG can be formed by, for example, a V-groove.

By forming such a guide groove GG along the movement direction, the sliding plate can also serve as a guide for removing backlash in the stage movement direction. Such a guide groove may be provided in the slide plate 52A' also in the Y direction.

In this embodiment, the stage mechanism is provided with both the pressure adjustment mechanism and the spheres arranged in a row along the direction perpendicular to the stage moving surface, but the stage mechanism can be provided without one of them. In this case, in order to enable free material selection with a simple member shape, the stage mechanism is provided with an X stage plate and a Y stage plate, and a plurality of spherical bodies are arranged in a row, and a conventional pressurization adjustment mechanism is used. It is possible to configure a stage mechanism using In addition, in order to facilitate pressure adjustment after assembly, a stage mechanism having the pressure adjustment mechanism described above can be constructed in which one stage plate is supported by a support plate.

Up to this point, the stage mechanism incorporated in the imaging device has been explained, but the stage mechanism described above can also be incorporated in other devices, and in any case, it is possible to realize a thin stage mechanism with a simple shape. can.

10 Stage Mechanism 20 Support Plates 21A to 21C Pressure Adjustment Mechanisms 22A to 22C Retainer 23A Pressure Piece 25A Spring 27A Pressure Adjustment Screw 30 Support Plate 32A Slide Plate 40 X Stage Plates 42A, 44A Slide Plate 50 Y Stage Plate 52A Sliding plates 80A to 80C Sphere 90 Sensor support plate 90A Image sensor 100 Imaging device

Claims (7)

a pair of support plates parallel to each other;
at least one stage plate supported by the set of support plates via a sphere and movable in a predetermined direction along the set of support plates;
A pressurization adjustment mechanism that applies pressurization to the sphere in contact with one support plate,
Between the pair of support plates sandwiching the stage plate, a plurality of spheres are arranged along a direction perpendicular to the moving direction of the stage plate,
The pressurization adjustment mechanism includes a spring, a screw that changes the deflection of the spring, and an urging member that transmits the elastic force of the spring to the sphere, and is capable of applying pressurization according to the amount of screwing. A stage mechanism characterized by: 2. The stage mechanism according to claim 1, wherein a slide plate having a hardness greater than that of said stage plate and coming into contact with the sphere is provided on the surface of said stage plate which is not provided with a hole for holding a sphere. 3. The slide plate provided on the surface of the stage plate and in contact with the sphere is provided with a guide groove for guiding the moving direction when the stage plate moves. Stage mechanism as described. a pair of support plates parallel to each other;
an X stage plate and a Y stage plate that are supported by the set of support plates via spheres and are movable along X and Y directions that are orthogonal to each other of the set of support plates;
A pressurization adjustment mechanism that applies pressurization to the sphere in contact with one support plate,
A sphere that keeps the distance between the one support plate and the X stage plate constant, a sphere that keeps the distance between the X stage plate and the Y stage plate constant, and the Y stage plate and the other support plate. A stage mechanism characterized in that spheres integrally maintaining a distance between and are arranged along a direction perpendicular to the moving direction of the stage plate. An imaging apparatus comprising the stage mechanism according to any one of claims 1 to 4. supporting at least one stage plate via a sphere by a pair of support plates parallel to each other so as to be movable in a predetermined direction along the pair of support plates;
A stage mechanism that applies pressure to a sphere that is in contact with one of the support plates by means of a pressure adjustment mechanism that includes a spring, a screw that changes the deflection of the spring, and an urging member that transmits the elastic force of the spring to the sphere. A method of supporting the
arranging a plurality of spheres in a direction perpendicular to the moving direction of the stage plate between the pair of support plates sandwiching the stage plate;
A method for supporting a stage mechanism, wherein a pressurization corresponding to a set screwing amount is applied to the pressurization adjusting mechanism. supporting the X stage plate and the Y stage plate by a pair of support plates parallel to each other via spheres so that the pair of support plates can move along X and Y directions perpendicular to each other;
A support method for a stage mechanism that applies pressure to a sphere in contact with one support plate, comprising:
A sphere that keeps the distance between the one support plate and the X stage plate constant, a sphere that keeps the distance between the X stage plate and the Y stage plate constant, and the Y stage plate and the other support plate. A method for supporting a stage mechanism, comprising: arranging spheres integrally spaced apart from each other in a direction perpendicular to the moving direction of the stage plate.

Images