JP2001042194A - Lens device and optical equipment - Google Patents

Abstract

(57) Abstract: When a guide member is held by a holding portion projecting from an inner surface of a lens housing member in an optical axis direction, a space for housing a lens or the like in the lens housing member is reduced, and the size of the apparatus is increased. Connect. SOLUTION: A lens accommodating member 5 having an accommodating opening for accommodating the movable lenses 2 and 4 movably in an optical axis direction, a lid member 18 attached to the lens accommodating member and closing the accommodating opening, and a lens In a lens device having guide members 10 and 11 for guiding the movable lens in the optical axis direction within the housing member, at least a wall portion formed at an optical axis end of the lens housing member has at least A holding portion 5e that positions and holds the guide member in the direction orthogonal to the optical axis outside the inner surface of the wall in the optical axis direction (for example, within the range of the wall thickness).
Is formed, and a movement restricting portion 18b for restricting movement of the guide member K held by the holding portion in the optical axis direction is provided on the lid member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens device combined with various optical instruments.

[0002]

2. Description of the Related Art Conventionally, a lens device is disclosed in
There is one disclosed in Japanese Patent No. 75521. FIG.
1 shows the configuration of the lens device disclosed in the above publication.
In this figure, reference numeral 103 denotes a lens housing member which is formed in a housing shape and houses a lens (not shown) so as to be movable in the optical axis direction (perpendicular to the paper surface). An accommodation opening 104 for guide bars 151 and 152 for guiding the lens in the optical axis direction is formed.

A bar holding portion 1 for holding the guide bar is provided on the inner surface of the lens housing member 103 in the optical axis direction.
11 and 112 are formed so as to protrude inward in the optical axis direction.

[0004] The axial ends of the guide bars 151 and 152 inserted into the lens housing member 103 from the housing opening 104 are fitted into concave portions 111a and 112a formed at the tips of the bar holding portions 111 and 112, respectively.

[0005] On the other hand, reference numeral 201 denotes a cover member which is attached to the lens housing member 103 by bonding or the like and closes the housing opening 104. Inside the lid member 201, bar pressing protrusions 202, 203 for pressing down the axial ends of the guide bars 151, 152 fitted in the concave portions 111a, 112a of the bar holding portions 111, 112 are formed. .

The tip surface 20 of the bar holding projections 202 and 203
By pressing down the axial ends of the guide bars 151 and 152 fitted in the bar holding portions 111 and 112 with 2a and 203a, the guide bars 151 and 152 are positioned in the direction orthogonal to the optical axis so that the lens housing member 10 is positioned.
3 supported. In addition, guide bars 151 and 152
The lens housing member 1 has an optical axis direction end surface abutting on the optical axis direction end surfaces of the concave portions 111a and 112a.
The movement in the optical axis direction within 03 is restricted.

[0007]

However, in the lens device disclosed in the above-mentioned publication, the bar holding portions 111 and 112 projecting from the inner surface of the lens housing member 103 in the optical axis direction and the projections are formed inside the lid member 201. There is a problem that the bar pressing projections 202 and 203 reduce the space for housing the lens and the like in the lens housing member 103. For this reason, there is a possibility that the degree of freedom in designing the lens device is reduced or the size of the device is increased.

In addition, the bar 201 must be provided with bar press projections 202 and 203 which require high precision and strength only for holding the guide bars 151 and 152, and also on the lens housing member 103 side. It is necessary to take measures to ensure the mounting accuracy and the mounting strength of the lid member 201.

It is assumed that a bar holding projection 202,
The bar holding portion 1 of the lens housing member 103 is not provided.
If the guide bars 151 and 152 are completely fixed to the bases 11 and 112 by bonding or welding, the accuracy and strength of the lid member are not required, but it is difficult to replace and repair a lens frame or the like fitted to the guide bar. There is a problem.

[0010]

In order to solve the above-mentioned problems, according to the present invention, there is provided a lens accommodating member having an accommodating opening for accommodating a movable lens so as to be movable in an optical axis direction. A lid member attached to close the storage opening,
And a guide member for guiding the movable lens in the optical axis direction in the lens housing member. In the lens device, at least a wall portion formed at an optical axis direction end of the lens housing member has at least Forming a holding portion for positioning and holding the guide member in the optical axis orthogonal direction outside the optical axis direction (for example, within the range of wall thickness) from the inner surface,
A movement restricting section is provided for restricting the movement of the guide member held by the holding section in the optical axis direction.

Specifically, the optical axis end of the guide member held by the holding portion is exposed to the outside of the lens housing member, and the movement restricting portion of the lid member is moved to the guide member outside the lens housing member. In the optical axis direction.

This eliminates the need for forming a projecting portion for holding the guide member inside the lens accommodating member as in the prior art, and effectively utilizes the space inside the lens accommodating member and downsizes the lens device accordingly. Can be achieved.

The holding portion is configured to elastically hold the guide member (for example, a reference surface portion serving as a reference for positioning the guide member, and an elastic portion pressing the guide member against the reference surface portion by an elastic force). Configuration), before attaching the lid member to the lens housing member,
The guide member can be held by the lens housing member in a state of being positioned in the direction orthogonal to the optical axis, and assembly can be facilitated.

Further, the cover member is provided with a pressing portion for applying a pressing force for fixing and holding the guide member to a holding portion (elastic portion) which elastically holds the guide member, so that the guide member is provided with a lens. It can be securely fixed to the housing member in the direction orthogonal to the optical axis.

According to these inventions, the lid member does not require any function other than the function of restricting the movement of the guide member in the optical axis direction and the function of shielding and dustproofing the lens housing member. Attachment can be performed by a simple method such as engagement with the lens housing member utilizing elastic deformation of the lid member.

[0016]

(First Embodiment) FIG. 1 shows the configuration of a lens device according to a first embodiment of the present invention. This lens device is mounted on a video camera and other optical devices.

In FIG. 1, reference numerals 1 to 4 denote lens groups which constitute an optical system of a general rear focus type zoom lens unit, and 1 denotes a first lens group which forms a fixed objective lens in order from the object side. 2 is a second lens group movable in the optical axis direction for zooming, 3 is a fixed third lens group,
Reference numeral 4 denotes a fourth lens group movable in the optical axis direction for zooming correction and focus adjustment of the zooming lens group 2.

In the drawing, each lens group may be constituted by one lens or may be constituted by a plurality of lenses.

Reference numeral 5 denotes a lens barrel body (lens housing member) having a housing shape for housing the lens groups 1 to 4, and an upper surface portion and a side surface portion on the front side thereof are provided inside the lens barrel body 5 with a lens and a guide described later. It is a storage port for inserting bars and the like.

At the center of the wall on the subject side of the lens barrel main body 5, a cylindrical portion projecting toward the subject to hold the first lens group 1 is formed. A bar holding portion 5e for holding a guide bar described later is formed on the left and right sides near the upper end of the wall portion on the subject side and the wall portion on the image forming side. A screw bearing portion 5f for rotatably holding a tip of a screw shaft described later is formed near the left and right ends of the wall portion on the subject side in the vertical direction.

Further, an engagement hole 5c for attaching a lid 18 to be described later is formed in the upper portion of the rear side wall portion of the lens barrel main body 5, and the lid 18 is attached to the front side of the lower wall portion. 5d are formed.

Reference numeral 6 denotes a second group holding frame for holding the second lens group 2, and reference numeral 7 denotes a third group holding frame for holding the third lens group 3. Reference numeral 8 denotes a fourth group holding frame for holding the fourth lens group 4, and reference numeral 9 denotes a mechanical opening / closing structure arranged between the second lens group 2 and the third lens group 3 for adjusting the amount of light. A diaphragm unit including the electric driving means.

Reference numeral 10 denotes a first guide bar which fits into the sleeve 6a of the second group holding frame 6 and guides the second group holding frame 6 in the optical axis direction. Reference numeral 11 denotes a sleeve 8a of the fourth group holding frame 8.
And a second guide bar that is fitted to and guides the fourth group holding frame 8 in the optical axis direction. The second group holding frame 6 has a long hole 6
At b, the second guide bar 11 is fitted, whereby the rotation around the first guide bar 10 is restricted. Further, the fourth group holding frame 8 is fitted to the first guide bar 10 at the elongated hole portion 8b, whereby the rotation around the second guide bar 11 is restricted.

Reference numeral 16 denotes a zoom rack integrally mounted on the sleeve portion 6a of the second group holding frame 6 in the optical axis direction. Reference numeral 12 denotes a zoom motor having a screw shaft meshing with the zoom rack 16 as an output shaft. . Reference numeral 17 denotes a focus rack integrally attached to the sleeve portion 8a of the fourth-group holding frame 8 in the optical axis direction. Reference numeral 13 denotes a focus motor having a screw shaft meshing with the focus rack 17 as an output shaft.

The zoom motor 12 and the focus motor 13 are respectively provided with screws 14 and 1 on the image forming side of the lens barrel body 5.
5 fixed.

Reference numeral 18 denotes a lid (lid member) for closing the accommodation opening of the lens barrel main body 5. At both ends in the optical axis direction on the upper surface of the lid 18, a movement restricting portion 18b is formed which extends downward and restricts the movement of the guide bars 10, 11 in the optical axis direction as described later. An engagement claw 18c that can be engaged from the outside with the engagement hole 5c of the lens barrel main body 5 is formed at a rear end of the upper surface. Further, an engagement hole 18d is formed in a lower portion of the side surface of the lid 18 so that the engagement hole claw 5d of the lens barrel main body 5 can be engaged from inside.

Reference numeral 19 denotes a zoom photo-interrupter which is fitted and held in a sensor hole formed in a rear side wall portion of the lens barrel main body 5 and detects an initial position of the second group holding frame 6. Also,
Reference numeral 20 denotes a focusing photo-interrupter which is fitted and held in a sensor hole formed on the lower surface of the lens barrel main body 5 and detects an initial position of the fourth-group holding frame 8.

Next, the assembling of the lens device having the above-described structure will be described with reference to FIGS.

First, the first lens group 1 is fixed to the cylindrical portion of the lens barrel main body 5 by a method such as caulking, bonding or welding.

Next, the second lens group 2 is fixed to the second group holding frame 6 by a method such as caulking, bonding or welding, and the zoom rack 16 is interposed with a loose play removing spring or the like (not shown). And make a second group unit.

Further, the third lens group 3 is fixed to the third group holding frame 7 by a method such as caulking, bonding or welding, and the aperture unit 9 is overlapped on the third group holding frame 7 to form a third group unit.

Further, the fourth lens group 4 is fixed to the fourth group holding frame 8 by a method such as caulking, bonding or welding, and the focus rack 17 is fixed to the fourth group holding frame 8 with a play spring (not shown) interposed therebetween. Assemble to make a 4 group unit.

After each group unit is assembled, the second to fourth group units are arranged on the optical axis, and the first and second guide bars 10 and 11 are connected to the corresponding elongated holes 6b, 8b and holes of each unit. The portion 7a is penetrated.

The internal parts integrated as described above are
The lens barrel body 5 is incorporated into the lens barrel holder 5 through the housing opening.
First, as shown in FIG.
The axial ends of 0 and 11 are dropped into the V-shaped reference surface portion 5a constituting the bar holding portion 5e, and the first and second ends are also formed by the elastic force of the elastic portion 5b constituting the bar holding portion 5e. The axial ends of the guide bars 10 and 11 are pressed against the reference surface portion 5a. Thus, the reference surface portion 5a
Guide bar 10 sandwiched between
Reference numeral 11 denotes a state where the lens 11 is positioned with respect to the lens barrel main body 5 in the direction orthogonal to the optical axis.

In the present embodiment, the bar holding portion 5e is formed within the wall thickness of the wall of the lens barrel main body 5 on the subject side and the image forming surface side, and does not protrude inside these wall portions.
For this reason, the movement range of the second lens group 2 (second group holding frame 6) in the optical axis direction is not limited by the presence of the bar holding section 5e, and the lens barrel main body 5 can be made smaller by that amount. Become.

The axial end surfaces of the guide bars 10 and 11 held by the bar holding portion 5e are exposed from the space between the reference surface portion 5a and the elastic portion 5b to the outside of the lens barrel body 5 in the optical axis direction. Become.

After the two guide bars 10, 11 and each group unit are assembled in the lens barrel main body 5, the zoom motor 12 is assembled and fixed to the main body lens barrel 5 while engaging the zoom rack 16 with its screw shaft. Similarly, the focus motor 13 is assembled and fixed to the main body barrel 5 while engaging the focus rack 17 with its screw shaft. At this time, the tip of the screw shaft is inserted and held in the screw bearing portion 5f of the lens barrel body 5.

Finally, as shown in FIGS. 3 and 4, the engaging claw 5d of the lens barrel main body 5 is engaged with the engaging hole 18d of the lid 18, and the elastic deformation of the entire lid 18 is further utilized. The engaging claw 18c of the lid 18 is engaged with the engaging hole 5c of the main body barrel 5.
Thereby, the lid 18 is fixed to the lens barrel main body 5, and the accommodation opening of the lens barrel main body 5 is closed.

When the cover 18 is fixed to the lens barrel main body 5 in this manner, as shown in FIG. 3, a pressing projection (pressing portion) 18a formed inside the cover 18 causes the elastic portion 5b to move to the reference surface portion. By pressing 5a, the elastic holding state in the direction orthogonal to the optical axis of the guide bars 10, 11 by the elastic portion 5b and the reference surface portion 5a is set to the fixed holding state.

Further, as shown in FIG. 4, the peripheral portion of the bar holding portion 5e of the lens barrel main body 5 is sandwiched between the movement restricting portions 18b on both sides of the lid 18 in the optical axis direction. The axial end surfaces of the guide bars 10 and 11 exposed to the outside in the optical axis direction from between the reference surface portion 5a and the elastic portion 5b abut on the movement restricting portion 18b.
Is prevented from moving in the optical axis direction (that is, coming off from the bar holding portion 5e).

The movement restricting portion 18b is provided with the reference surface portion 5
a of the elastic portion 5b.
As a result, the space surrounded by the lens barrel main body 5 and the lid 18 is a light-shielding / dust-proof space in which outside light from other than the first lens group 1 is blocked and entry of any dust and dust is blocked. Become.

When driving the lens device assembled in this manner, first, a rib-shaped portion (not shown) formed on the second group holding frame 6 enters between the light emitting portion and the light receiving portion of the zoom photo interrupter 19. The zoom motor 12 is driven to a position where light is blocked. Similarly, the focus motor 13 is driven to a position where a rib-shaped portion (not shown) formed on the fourth group holding frame 8 enters between the light emitting portion and the light receiving portion of the focusing photo interrupter 20 and blocks light. This gives 2
The reference positions of the group holding frame 6 and the fourth group holding frame 8 are determined, and the zoom motor 12 and the focus motor 13 are driven and controlled in accordance with a signal from a control circuit (not shown) with this position as an initial position. Zooming and focusing are performed.

By using a stepping motor as both motors 12 and 13, open loop control can be performed. Specifically, signals from the photo interrupter for zoom 19 and the photo interrupter for focus 20 are detected by a control circuit, and the position control of the zoom motor 12 and the focus motor 13 is performed based on the detected signals.

At this time, a memory (not shown) stores the focal length of the present lens apparatus and correction lens data corresponding to the focal length of the lens apparatus, so that more precise control can be performed.

Further, by mounting a solid-state image pickup device (CCD) on the image-forming surface side of the lens barrel main body 5, not only an image can be captured but also a high-precision focus determination can be performed. By driving the focus motor 13 until it is within the range, the automatic focus adjustment by the feedback control method can be performed.

(Second Embodiment) In the first embodiment,
Guide bars 10 and 1 in the same direction on the left and right of the upper part
Although the description has been given of the case where the bar holding portion 5e sandwiching the first bar holding portion 5e is provided, for example, as shown in FIG. 5, one bar holding portion 5e is formed so as to sandwich the guide bar 10 in the vertical direction, and 'Is a guide bar 1
1 may be formed therebetween.

That is, the holding (holding) directions of the guide bars in the holding portions for holding the two guide bars may be different from each other.

In the above embodiment, the case where the bar holding portion 5e is formed within the wall thickness of the wall portion of the lens barrel main body 5 has been described. However, if the holding portion does not protrude inside the wall portion,
You may form so that it may protrude outside. However, it is desirable that the amount of protrusion be equal to or less than the thickness of the movement restricting portion 18b formed on the lid 18, for example.

The shapes of the lens housing member and the cover member in the present invention are not limited to those described in the above embodiments, but may be various shapes having the same function.

[0050]

As described above, according to the present invention,
Since it is not necessary to form a protruding portion for holding the guide member inside the lens housing member as in the related art, it is possible to effectively use the space inside the lens housing member and downsize the lens device accordingly. .

Further, when the holding portion of the guide member formed on the lens accommodating member elastically holds the guide member, the lid member fixes and holds the guide member to the holding portion. By providing the pressing portion for applying the pressing force, the guide member can be securely fixed to the lens housing member in the direction orthogonal to the optical axis.

According to these inventions, the lid member does not need any function other than the function of restricting the movement of the guide member in the optical axis direction and the function of shielding and dustproofing the lens housing member. Attachment can be performed by a simple method such as engagement with the lens housing member utilizing elastic deformation of the lid member, and improvement in assemblability can be achieved.

Further, by using the lens device according to the invention described above, it is possible to reduce the size and cost of the optical equipment.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a configuration of a lens device according to a first embodiment of the present invention.

FIG. 2 is an external view of the lens device as viewed in the optical axis direction.

FIG. 3 is a cross-sectional view of the lens device as viewed in the optical axis direction.

FIG. 4 is a cross-sectional view of the lens device as viewed in a direction perpendicular to the optical axis.

FIG. 5 is an external view of a lens device according to a second embodiment of the present invention as viewed in the optical axis direction.

FIG. 6 is a sectional view showing a conventional lens device.

[Explanation of symbols]

 1. First lens group 2. Second lens group 3. Third lens group 4. Fourth lens group 5. Barrel main body 5e Bar holder 5a Reference surface portion 5b Elasticity Part 5f Screw bearing 6 Group 2 holding frame 7 Group 3 holding frame 8 Group 4 holding frame 9 Aperture unit 10, 11 Guide bar 12 Zoom motor 13 Focus motor 16. Zoom rack 17 Focus rack 18 Lid 19 Photo interrupter for zoom 20 Photo interrupter for focus

Claims (11)

[Claims] A lens accommodating member having an accommodating opening for accommodating the movable lens movably in the optical axis direction; a lid member attached to the lens accommodating member to close the accommodating opening; And a guide member that guides the movable lens in the optical axis direction at: a wall portion formed at an optical axis direction end of the lens housing member;
A holding portion for positioning and holding the guide member in the optical axis orthogonal direction at least outside the inner surface of the wall in the optical axis direction is formed, and the cover member has a light guide member held by the holding portion. A lens device provided with a movement restricting portion for restricting movement in an axial direction. 2. The lens device according to claim 1, wherein the holding portion is formed within a range of a wall thickness of the wall portion. 3. The lens device according to claim 1, wherein the holding section elastically holds the guide member before attaching the lid member. 4. The lid member is provided with a pressing portion for applying a pressing force for fixing and holding the guide member to the holding portion elastically holding the guide member. 3. The lens device according to item 3. 5. The holding section includes a reference surface portion serving as a reference for positioning the guide member, and an elastic portion for pressing the guide member against the reference surface portion by an elastic force. The lens device according to claim 3, wherein 6. The lid member is provided with a pressing portion for pressing the elastic portion holding the guide member toward the reference surface portion between the lid member and the reference surface portion. The lens device according to item 1. 7. An optical axis direction end of the guide member held by the holding portion is exposed outside the lens housing member, and the movement restricting portion of the lid member is provided outside the lens housing member. The lens device according to claim 1, wherein the lens device abuts on an end of the guide member in the optical axis direction. 8. The apparatus according to claim 1, wherein the movement restricting portion has a shape that closes a gap formed in the holding portion.
8. The lens device according to any one of items 1 to 7. 9. A lens accommodating member having an accommodating opening for accommodating the movable lens movably in the optical axis direction, a lid member attached to the lens accommodating member and closing the accommodating opening; And a guide member that guides the movable lens in the optical axis direction. A holding portion that elastically holds the guide member is formed in the lens housing member, and the lid member A lens unit provided with a pressing unit for applying a pressing force for fixing and holding the guide member to the holding unit elastically holding the guide member. 10. The method according to claim 1, wherein the attachment of the lid member to the lens accommodation member is performed by engagement with the lens accommodation member using elastic deformation of the lid member. The lens device according to any one of the preceding claims. 11. An optical apparatus comprising the lens device according to claim 1.