JPH116949A - Photographing lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact photographing lens barrel where the degree of freedom in design is increased while sufficiently supporting plural operation rings and securing space for arranging an internal mechanism such as an encoder. SOLUTION: This photographing lens barrel is equipped with photographing optical systems L1, L2 and L3, plural operation members 60 and 70 which can rotate centered on the optical axis C of the photographing optical system, the internal mechanisms 80, 102, 103 and 201 performing actions related to photographing based on the rotation of the operation members, and a fixed member 500 supporting the internal mechanisms and the operation members. In such a case, the member 500 supports the internal mechanism on its outer surface 520a and supports plural operation members by a separate member 151 separately provided to be opposed to the outer surface and extended in an optical axis direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographic lens barrel having an operation ring for zooming, focusing, and the like.

[0002]

2. Description of the Related Art As a conventional photographing lens barrel, for example, there is one as shown in FIG. FIG. 3 is a longitudinal sectional view of a conventional photographing lens barrel. This lens barrel includes a plurality of lens groups L1, L2, and L3 arranged on the optical axis C, and first, second, and third lens frames 10 that respectively support the lens groups L1, L2, and L3. , 20, 40, a fixed barrel 50 having a mount portion 51 for mounting to a camera body (not shown), a zoom operation ring 60 for performing a zoom operation, a focus operation ring 70 for performing a focusing operation, Spiral cam groove 8 around optical axis C
2 and 83 are provided.

The fixed cylinder 50 has a cylindrical portion 52 and flange portions 53, 54 formed on the outer peripheral surface of the cylindrical portion 52.
And the mount 51 described above. Fixed cylinder 50
A zoom operation ring 60 is radially fitted on the outer peripheral side of the flange portion 54, is rotatably supported around the optical axis C, and an outer cylinder 110 is fixed to the side surface by screws 111 as shown in the figure. I have. A focus operation ring 70 is screw-fitted on the outer peripheral side of the flange portion 53, and is provided rotatably around the optical axis C. Further, a focusing rectilinear groove 75 extending in a direction parallel to the optical axis C is formed on the inner peripheral side of the focus operation ring 70.

On the outer peripheral side of the cylindrical portion 52 of the fixed cylinder 50, a cam cylinder 80 as shown in FIG.
The projection 53b that has passed through b is disposed so as to be rotatable around the optical axis C in a state of fitting. On the cam cylinder 80, a connecting member 65 is fixed by a screw 100. The connecting member 65 passes through a notch 53a of the flange 53 and is inserted into a notch 60a of the zoom operation ring 60 as shown in the figure. It is fitted.

The cam ring 80 has a cam groove 82 for the second lens group and a cam groove 83 for the third lens group so as to spirally penetrate around the optical axis C from the inner peripheral side to the outer peripheral side. Have been. The cylindrical portion 52 of the fixed cylinder 50 is formed with zooming rectilinear grooves 57 and 58 extending in a direction parallel to the optical axis C and penetrating from the inner peripheral side to the outer peripheral side. The third lens frame 40 includes a third lens supporting portion 41 that supports the third lens unit L3, a straight cylindrical portion 42 that slides on the inner peripheral surface of the cylindrical portion 52 of the fixed barrel 50, and a straight cylindrical portion 42. And a male helicoid 44 formed at the subject side end (left side in the drawing). A relief groove 43 penetrating from the inner peripheral side to the outer peripheral side is formed in the straight cylindrical portion 42 of the third lens frame 40.

The second lens frame 20 supporting the second lens unit L2 is arranged on the inner peripheral side of the straight cylindrical portion 42 of the third lens frame 40 so as to be movable in the direction of the optical axis C.

The first lens frame 10 has a third lens frame 4
The outer cylinder 13 and the first lens support 11 that supports the first lens unit L1 are formed on the outer circumference of the male helicoid part 44 and on the inner circumference of the focus operation ring 70. A female helicoid portion 14 is formed on the inner peripheral side of the outer cylindrical portion 13 to which the male lyricoid portion 44 of the third lens frame 40 is screwed. The connecting projection 15 is formed to fit into the focusing straight groove 75 of the operation ring 70.

The third lens group cam pin 94 protrudes from the outer peripheral side of the straight cylindrical portion 42 of the third lens frame 40 and passes through the zooming rectilinear groove 57 of the cylindrical portion 52 of the fixed barrel 50.
The cam barrel 80 is fitted in the third lens cam groove 83. The cam pin 92 for the second lens group projects from the outer peripheral side of the second lens frame 20, passes through the clearance groove 43 of the straight cylindrical portion 42 of the fourth lens frame 40, and further passes through the cylindrical portion of the fixed barrel 50. 52 through the zooming straight groove 58 of the cam cylinder 80
In the second lens group cam groove 82. In addition,
The cam pins 92 and 94, the cam grooves 82 and 83, and the like are also provided at symmetrical positions about the optical axis C.

The above-described taking lens barrel operates as follows. When the zoom operation ring 60 is rotated around the optical axis C, the cam barrel 80 is also rotated around the optical axis C accordingly. The cam pins 92 and 94 fitted into the cam grooves 82 and 83 move in a direction parallel to the optical axis C by the rotation of the cam cylinder 80. As a result, the third lens frame 40 on which the third lens group cam pin 94 protrudes,
The first screwed into the male helicoid part 44 of the lens frame 40
Moves in the direction of the optical axis C, and the third lens group L3 and the first lens group L1 supported by these lens frames 40 and 10 move in the direction of the optical axis C. Also, the second
The second lens frame 20 on which the lens group cam pin 92 protrudes moves in the direction of the optical axis C, and the second lens frame 2
The second lens unit L2 supported at 0 also moves in the direction of the optical axis C.

When the focus operation ring 70 is rotated around the optical axis C, the first lens frame 1 is rotated with this rotation.
0 also rotates around the optical axis C. This first lens frame 10
Since the female helicoid portion 14 on the inner peripheral side of the outer cylindrical portion 13 is screwed with the male helicoid portion 44 of the third lens frame 40,
It moves in the direction of the optical axis C while rotating around the optical axis C. Therefore, the first lens unit L1 supported by the first lens frame 10 also moves in the direction of the optical axis C, and focus adjustment is performed.

At the rear end of the focus operation ring 70, between the flange 53 and the flange 54 of the fixed cylinder 51, a support member 102 with a brush 103 caulked is a screw 10.
4 fixed. The brush 103 is a flexible printed circuit board 2 provided with a pattern for an encoder.
01 is disposed so as to be in sliding contact with the uppermost portion 01. The connecting member 65 and the supporting member 102 are arranged so that their operating angle ranges do not overlap so that they do not interfere with each other.

[0012]

In the photographing lens barrel having such a configuration, in order to secure a mounting space for the flexible printed circuit board 201 on the outer periphery of the cylindrical portion 52 and to rotatably support the cam ring 80. Projection 53b
In order to form the rotary support portions (flange portions 53, 54) of the two operation rings 60, 70 integrally with the cylindrical portion 52, as shown in FIG. For this reason, it cannot be provided so as to overhang the outer peripheral surface of the cylindrical portion 52. For this reason, it is not possible to secure a sufficient fitting length in the optical axis direction of the rotation support portion for supporting the zoom operation ring and the focus operation ring on the fixed cylinder, and rattling becomes large when operating the operation ring. There was a case where such a problem occurred. Conversely, if the flange portions 53 and 54 are configured to be thick in the direction of the optical axis C in order to suppress such rattling, the mountable space for an encoder or the like becomes narrower or the lens barrel becomes longer. And other problems arise.

The present invention solves such a conventional problem,
An object of the present invention is to provide a compact photographing lens barrel that has a sufficient degree of design freedom while sufficiently supporting a plurality of operation rings and securing a space for disposing an internal mechanism such as an encoder.

[0014]

In order to achieve the above object, a photographic lens barrel according to the present invention comprises: a photographic optical system; a plurality of operation members rotatable around an optical axis of the photographic optical system; In a photographic lens barrel including an internal mechanism that performs a photographing-related operation based on rotation of an operation member, and a fixing member that supports the internal mechanism and the operation member, the fixing member supports the internal mechanism on an outer surface. In addition, the plurality of operation members are supported by another member separately provided so as to extend in the direction of the optical axis so as to face the outer surface.

According to the present invention, since the separate member faces the outer surface of the fixed member and extends in the optical axis direction, a sufficient area for supporting the plurality of operation members can be ensured, and the operation member is rattled. And the like can be prevented. In addition, even if another member is opposed to the outer surface and extends in the optical axis direction, since this separate member is provided separately from the fixing member, there is no obstacle in performing machining or plastic molding.

Further, a projection may be integrally formed on the outer surface to be engaged with a constituent member of the internal mechanism, and the separate member may be provided on the outer surface on which the projection is formed so as to protrude. .

According to this configuration, even when the protrusion is provided on the outer surface of the fixing member and another member overhangs and protrudes from the outer surface, there is no problem in processing the fixing member.

The fixing member may have a flange extending from the outer surface in a direction orthogonal to the optical axis, and the separate member may be attached to the flange.

According to this configuration, the separate member can be attached to the fixed member, and the operating member is not supported by the flange portion. Therefore, it is not necessary to increase the thickness of the flange portion in the optical axis direction, and the arrangement for the internal mechanism is not required. A compact shooting lens barrel can be realized while securing sufficient space.

Further, the plurality of operation members can be constituted by a zoom operation member and a focus operation member.

[0021] The internal mechanism may include a cam mechanism for moving the photographing optical system, and the constituent member may be a cam member rotatably held around the optical axis on an outer surface of the fixed member.

Further, the internal mechanism may include a detecting means for detecting information relating to the photographing-related operation, and the detecting means may be arranged in a gap between the outer surface of the fixed member and the separate member.

Further, the detecting means may be constituted by an encoder which comprises a printed board and a brush and detects information relating to the photographing-related operation.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a taking lens barrel according to an embodiment of the present invention. Note that portions having the same functions as those of the conventional photographing lens barrel of FIG. 3 described above are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 1, the fixed barrel 500 has a cylindrical portion 52 for supporting the cam barrel 80 and the like on its outer peripheral surface 520a.
0, and a flange portion 550 extending from the outer peripheral surface 520a of the cylindrical portion 520 to the inner peripheral side near the rear end of the zoom operation ring 60 in a direction perpendicular to the optical axis C. Flange part 5
50 is formed integrally with the cylindrical portion 520, and has a screw hole 550a for attaching an operation ring support member 151 described later.

The operating ring support member 151 is formed in a cylindrical shape, is attached to a flange 550, and extends from the flange 550 in front of the lens barrel in parallel with the optical axis C.
The projection 530b provided on the outer peripheral surface 520a of the cylindrical portion 520 of the fixed cylinder 500 extends beyond the position in the direction of the optical axis C.

The operation ring support member 151 has its tip end (subject side) positioned between the inner peripheral surface of the zoom operation ring 60 and the outer peripheral surface of the focus operation ring 70, and its rear end side inside the zoom operation ring 60. It is arranged so as to be located between the peripheral surface and the end surface 550b of the flange portion. As a result, the operation ring support member 151 moves the zoom operation ring 60 on its outer peripheral surface.
Are rotatably supported on the inner peripheral surface of the focus support ring 70.

The operating ring supporting member 151 has a protruding portion 15 bent at its rear end so as to protrude in the direction of the optical axis C.
1f, and the protrusion 151f is fixed to the flange 550 by screwing the screw 152 into the screw hole 550a of the flange 550.
51 is attached to the fixed cylinder 500. The operation ring support member 151 has a notch 6 of the zoom operation ring 60.
0a so that the connecting member 65 inserted into the hole
1e is formed.

As described above, the zoom operation ring 60 and the focus operation ring 70 are connected to the flange 550 of the fixed barrel 500.
Are rotatably supported on the inner peripheral portion and the outer peripheral portion of the operation ring support member 151 attached to the control ring.

A peripheral groove 151a is provided on the outer periphery of the operation ring support member 151, and a peripheral groove 151b is provided on the inner periphery. The operation ring support member 15 is provided in each of the peripheral grooves 151a and 151b.
1 are provided with straight grooves 151c and 151d, respectively, which are connected to the respective end faces. FIG. 2 shows the operation ring support member 151.
FIG. 7 is a diagram showing a circumferential position of a rectilinear groove 151c as viewed from the rear end side (camera side). As shown in FIG.
Are divided into four equal parts in the circumferential direction and four are formed at 90 ° intervals.

FIG. 2 also shows a view of the zoom operation ring 60 viewed from the rear end side. The zoom operation ring 60 has a circular protrusion 60b projecting inward from the rear end. It is divided into four equal parts in the circumferential direction and four are formed at 90 ° intervals.

As shown in FIG. 2, each projection 60b of the zoom operation ring 60 is connected to each straight groove 151c of the operation ring support member 151.
Adjust to In this state, the zoom operation ring 60 is pushed leftward from the right side in FIG. 1 and incorporated into the operation ring support member 151, so that the projection 60b is used in a state where the protrusion 60b is accommodated in the circumferential groove 151a. After the zoom operation ring 60 is assembled,
In a normal operation, the angular positions of the protrusion 60b and the rectilinear groove 151c match, and the rotation is regulated so as not to come off. For example, in the example shown in FIG. 2, the rotation angle of the zoom operation ring 60 is less than 90 °.

The focus operation ring 70 has a projection 70a protruding on the outer peripheral side near the rear end thereof. As in the above-described case, the projection 70a is aligned with the straight groove 151d and pushed rightward from the left side in the drawing to operate. By being incorporated in the ring support member 151, the projection 70a is used in a state of being accommodated in the circumferential groove 151b. After the focusing operation ring 70 is assembled,
In a normal operation, the rotation is regulated in the same manner as described above so that the angular positions of the protrusion 70a and the straight groove 151d do not coincide with each other and do not come off.

As described above, the built-in structure of the operation rings 60 and 70 and the operation ring support member 151 is different from that of the projections 60b and 70
is engaged with the rectilinear grooves 151c and 151d, and the protrusions 60 are formed in the circumferential grooves 151a and 151b formed therein from the rectilinear grooves.
a and 70a are configured to slide. Therefore,
In order to prevent the engagement from being unexpectedly released, if a plurality of protrusions are formed equally in the circumferential direction, the rotation angle of the operation ring is less than (360 ° / n), where n is the number of protrusions. It is configured to be regulated.

The rear end of the cam ring 80 and the flange 55
0, and the supporting member 102 with the brush 103 caulked is provided on the cylindrical surface 520a of the fixed cylinder 520.
4 fixed. Flexible printed circuit board 20 provided with brush 103 and encoder pattern
1 constitutes an encoder. The pattern for the encoder on the flexible printed circuit board 201 is connected to a CPU (not shown) provided in the lens barrel,
U sends the distance information obtained from the encoder to the camera body while being attached to the camera body.

According to such a configuration, since the operation ring support member 151 is provided separately from the cylindrical portion 520 of the fixed cylinder 500, the protrusion 530b of the operation ring support member 151 is provided.
Forming and machining can be performed without worrying about overhang. For this reason, it is possible to extend the operation ring support portion in the direction of the optical axis C, and it is possible to secure a large area for supporting the operation rings 60 and 70 in the operation ring support member 151, and to operate the operation rings 60 and 70 during operation. The occurrence of rattling can be suppressed.

Further, the cam ring 8 which is a component of the internal mechanism
0 can be moved rightward in the drawing as far as space allows, so that the projection 530b for rotatably holding the optical axis C around the optical axis C of the optical system can be moved to the right of the drawing. It is effective for downsizing.

Further, only the flange portion 550 provided on the cylindrical portion 520 for supporting the operation rings 60 and 70 is required, and the flange portion 550 itself is also provided on the operation rings 60 and 7.
What is necessary is just to secure the minimum thickness required for strength so that the operating ring support member 151 supports 0. Therefore, like the flange portions 53 and 54 of the conventional lens barrel in FIG.
It is not necessary to secure the fitting length of the optical axis 70 in the direction of the optical axis C. Therefore, it is easy to secure a space for incorporating an internal mechanism such as an encoder used for performing a photographing-related operation, and the degree of design freedom is increased.

Since the operation rings 60 and 70 are supported on the inner and outer circumferences of the operation ring support member 151 with good space efficiency, the radial compactness is hardly impaired as compared with the conventional case.

It should be noted that the present invention is not limited to the embodiments described above, and various modifications or changes are possible within the scope of the technical idea of the present invention, and these are also within the scope of the present invention. For example, the operation ring is not limited to the illustrated one, and may be an operation ring for switching between auto focus and manual focus.

The protrusion 530b of the cylindrical portion 520 is
Although the cam ring has a function of freely rotating and supporting the cam ring, the cam ring may be moved to another position to function as a rotation limit of the cam ring itself.

The components in the internal mechanism are not limited to the illustrated cam ring.
An F gear train or the like may be used. In this case, the convex portion for supporting the component members in the internal mechanism with respect to the fixed cylinder,
A flange-like projection or the like for fixing the gear base plate may be considered.

[0043]

According to the present invention, it is possible to provide a compact photographing lens barrel which sufficiently supports a plurality of operation rings, secures a space for disposing an internal mechanism, and increases design flexibility. Can be.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a taking lens barrel according to an embodiment of the present invention.

FIG. 2 is a front view of an operation ring support member of the taking lens barrel shown in FIG.

FIG. 3 is a longitudinal sectional view of a conventional photographing lens barrel.

[Explanation of symbols]

 Reference Signs List 60 zoom operation ring 70 focus operation ring 80 cam ring 151 operation ring support member (separate member) 500 fixed ring (fixed member) 520 cylindrical portion 520a outer peripheral surface 530b projecting portion 550 flange portion

Claims (7)

[Claims] A photographing optical system; a plurality of operation members rotatable around an optical axis of the photographing optical system; an internal mechanism for performing a photographing-related operation based on rotation of the operation member; And a fixing member supporting the operation member,
Wherein the fixing member supports the internal mechanism on an outer surface, and the plurality of fixing members are provided by another member separately provided so as to extend in the direction of the optical axis in opposition to the outer surface. A photographing lens barrel that supports the operation member of (1). 2. A projection which is integrally formed on the outer surface to engage with a component member of the internal mechanism, and wherein the another member is provided so as to project on the outer surface on which the projection is formed. Item 2. The taking lens barrel according to Item 1. 3. The imaging device according to claim 1, wherein the fixing member has a flange portion extending from the outer surface in a direction orthogonal to the optical axis, and the separate member is attached to the flange portion. Lens barrel. 4. The photographic lens barrel according to claim 1, wherein the plurality of operation members are a zoom operation member and a focus operation member. 5. The internal mechanism includes a cam mechanism for moving the photographing optical system, and the constituent member is a cam member rotatably held on an outer surface of the fixed member around the optical axis. The imaging lens barrel according to 1, 2, 3 or 4. 6. The apparatus according to claim 1, wherein the internal mechanism includes a detecting unit configured to detect information regarding the photographing-related operation, and the detecting unit is disposed in a gap between the outer surface of the fixed member and the separate member. , 2, 3, 4 or 5. 7. The photographic lens barrel according to claim 6, wherein said detection means is an encoder which includes a printed circuit board and a brush and detects information relating to said photographic-related operation.