JPH05134159A - Lens-barrel - Google Patents

Abstract

PURPOSE:To stabilize motion of a flexible printed substrate for transmitting electric signals to be folded for storage, to prevent the substrate from invading in a photographing optical axis when it is folded and piled and to reduce its manufacturing cost. CONSTITUTION:In a lens barrel including a zoom lens for changing the focal distance by the interval change of plural lens groups 5a-5c disposed on the optical axis and a flexible printed substrate 14 for transmitting an electric signal from one of lens groups 5b, the flexible printed substrate 14 comprises the first arm portion 14a deformed to be U-shaped by the movement of the lens groups, one end of which is fixed to a shutter unit 13 integral with the lens group 5b, the other end thereof being fixed to a movable member 16 having a little travel to the lens group, and a second arm portion 14b deformed to be U-shaped by the movement of a movable member 16, one end of which is connected to the movable member 16, the other end thereof being connected to a control circuit of a camera main body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zoom lens which changes a focal length by changing a distance between a plurality of lens groups arranged on an optical axis, and a flexible print which transmits an electric signal from one of the lens groups. The present invention relates to a lens barrel having a substrate.

[0002]

2. Description of the Related Art Conventionally, in a camera with a built-in zoom lens, in order to control a shutter, a zoom drive motor, etc. attached to a lens group moving in a zoom lens barrel by a control circuit mounted on the camera body, It is known that a flexible printed circuit board (hereinafter referred to as "flexible") is used to electrically connect and transmit an electric signal.

6 to 8 are vertical sectional views showing a conventional lens barrel, FIG. 6 is a wide state diagram of a zoom lens, and FIG. 7 is a tele state diagram.

In FIGS. 6 and 7, reference numeral 1 is a camera body (hereinafter referred to as a body) including a film feeding system (not shown), and 2 is a spool configured to wind a film 4 from a cartridge 3. 5 is a first group lens 5a, a second group lens 5
b is a zoom lens having a three-group configuration of a third-group lens 5c.

Reference numeral 6 denotes a zoom ring outer cylinder fixed to the main body 1, and 7
Reference numeral 8 denotes a zoom ring inner cylinder which is fitted in the inner diameter of the zoom ring outer cylinder 6 and moves straight, and 8 denotes a zoom drive ring which is rotated by a motor 9 and a reduction gear system (not shown).

Reference numeral 10 denotes a second group base plate holding a second group lens 5b. The second group base plate 10 is provided with the zoom drive ring 8, a motor 9, and a reduction gear system (not shown). The drive ring 8 is rotatably attached to the second group base plate 10 by a holding plate 11. The second group base plate 10 is engaged with the straight-moving grooves of the zoom ring inner cylinder 7 and the zoom ring outer cylinder 6 by a zoom roller (not shown), and is prevented from rotating by the straight groove of the zoom ring outer cylinder 6, and the zoom ring inner cylinder is It runs straight with 7 stopped.

The first group lens 5 is attached to the tip of the zoom ring inner cylinder 7.
A first-group base plate 12 holding a is attached, and moves linearly integrally with the zoom ring inner cylinder 7. Zoom drive ring 8
Also, a zoom roller (not shown) is attached to each of the zoom ring inner cylinder 7 and the zoom ring outer cylinder 6 and is engaged with the feeding cam groove.

The zoom ring outer cylinder 6 has a feeding cam (not shown) of the second group base plate 10, and the zoom ring inner cylinder 7 has the first group lens 5
A differential cam (not shown) between the second lens group 5a and the second lens group 5a is provided, and the zoom driving ring 8 is rotationally driven by the motor 9 and a reduction gear system (not shown). Is configured to pay out.

In this case, the first group lens 5a has a lens configuration in which the operating amount is smaller than the operating amount of the second group lens 5b, and the second group lens 5b is relatively the first group lens 5
It is configured to approach a.

The third group lens 5c is held on the second group base plate 10 by a bar (not shown), and a cam (not shown) provided on the zoom drive ring 8 moves the second group base plate 10 when the zoom drive ring 8 rotates. Is configured to do.

Reference numeral 13 denotes a shutter unit attached to the second group base plate 10, and this shutter unit 13 is connected to a main substrate 15 including a control circuit attached to the main body 1 by a connection flexible 100.

FIG. 8 shows the outer shape of the connection flexible member 100. The right side of the drawing is attached to the shutter unit 13, and the left side of the drawing is connected to the main board 15. Further, a pattern for connecting the above-mentioned zoom driving motor 9 to the main board 15 is also provided.

Reference numeral 101 denotes a light-shielding cylinder which is engaged with the inside of the main body 1. The light-shielding cylinder 101 moves straight in such a manner that it follows the zoom ring inner cylinder 7 by a spring (not shown), and the engagement with the main body 1 does not come off a little before the tele end. In this way, the follow-up of the zoom ring inner cylinder 7 is stopped and stopped in the state shown in FIG.

With the above configuration, the zoom drive ring 8
7 rotates from the wide state shown in FIG.
Operates in the tele state shown in or vice versa.

At the wide end of the zoom lens of FIG. 6,
The connection flexible member 100 is housed in a state of being folded into an S shape, and straightened as it moves to the tele end of FIG. On the contrary, when operating from the tele end of FIG. 7 to the wide end of FIG. 6, the straight connecting flexure 100 is folded into an S shape.

[0016]

However, in the above-mentioned conventional example, it is difficult to stabilize the bent shape when the connecting flex is bent into an S-shape, and the bent connecting flex is in the optical path of the photographing optical system at the wide end. Sometimes I say yes. At the telephoto end, the straight surface of the connecting flex may cause internal reflection, so that antireflection coating or the like must be applied to the surface. Also,
There has been a problem that the arm portion of the connection flexible becomes long, a large area is required for manufacturing the connection flexible, and the cost increases.

An object of the present invention is to provide a lens barrel which solves the above problems.

[0018]

According to the present invention, a zoom lens that changes the focal length by changing the distance between a plurality of lens groups arranged on the optical axis, and an electric signal from one of the lens groups is used. In a lens barrel having a flexible printed circuit board for transmission, the flexible printed circuit board has one end fixed to a shutter integrated with the lens group and the other end fixed to a moving member having a small movement amount with respect to the lens group, The first arm that is deformed into a U shape by the movement of the lens group, one end of which is connected to the moving member and the other end of which is connected to the control circuit of the camera body, and the movement of the moving member causes U
By including the second arm that deforms into a letter shape, the folded connection flexion is prevented from entering the shooting optical axis, and the connection flexion is oriented so that internal reflection does not occur, and the area for producing the connection flexi Can be reduced to reduce costs.

[0019]

1 to 5 show an embodiment of the present invention. The same parts as those in the conventional example shown in FIGS. In FIGS. 1 to 5, reference numeral 14 is a connection flexure, and this connection flexure 14e is, as shown in FIG. 5, a first arm portion 14a and a second arm portion 14b.
The common ends 14e of both arms are fixed to the light shielding tube 16, the wiring portion 14c of the first arm portion 14a is fixed to the shutter unit 13, and the connector portion 14d of the second arm portion 14b is the main body. It is fixed to the main board 15 attached to the No. 1.

The light-shielding cylinder 16 is the above-described conventional light-shielding cylinder 1.
The same operation as that of 01 is performed.
It is configured to follow the zoom ring inner cylinder 7 that operates integrally with the group lens 5a, and is arranged between the main body 1 and the second group base plate 10 that holds the second group lens 5b. Then, the operation of the second group base plate 10 is slightly delayed, and the linear movement is performed following the second group base plate.
Less than 0 actuation.

3 and 4 are perspective views showing the operating state of the connection flexible member 14, FIG. 3 showing the respective states at the wide end and FIG. 4 showing the respective states at the tele end. As shown in FIG.
At the wide end, the first arm portion 14a is folded in a U-shape between the shutter unit 13 and the light shielding tube 16 in a direction perpendicular to the photographing optical axis, and the second arm portion 14b is folded in the light shielding tube 16.
It is folded in a U-shape between the main body 1 and the main body 1 in a direction perpendicular to the photographing optical axis.

As the zooming operation is performed from the wide end shown in FIG. 3, the first arm portion 14a is pulled up by the operation of the second group base plate 10 to which the shutter unit 13 is fixed as the first arm portion 14a is moved to the tele state shown in FIG. Be done. At this time, since the light-shielding cylinder 16 is operating following the zoom ring inner cylinder 7 that is operating integrally with the first group lens 5a, the light-shielding cylinder 16 moves following the operation of the second group base plate 10 with a slight delay.
The second arm portion 14b is formed such that the space between the light shielding tube 16 and the light shielding tube 16 is opened.
Is also stretched.

[0023]

As described above, according to the present invention,
Almost the middle part of the bending arm part of the connection flex that is fixed and operates in one of the lens groups that operate in the zoom lens,
By fixing it to an actuating member with an actuating amount smaller than the actuating amount of this lens group and bending this connecting flex into a U-shape in a direction perpendicular to the photographing optical axis, the folding operation of the connecting flex is stabilized and folded. It is possible to prevent accidents in which a connected flexible cable enters the shooting optical axis.

Further, when the connecting flexible member is bent in a direction perpendicular to the photographing optical axis, when the connecting flexible member is stretched at the tele end, the surface of the connecting flexible member does not face the photographing optical axis side, and thus the inner surface is not formed. There is no reflection. Then, the connection flex can be folded back into a horseshoe shape with the middle part that fixes the arm part for bending to the actuation member as a boundary, and the area on the connection flex can be changed to the area on the conventional connection flex. Compared to this, it can be made significantly smaller, and there is an effect that the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view in a wide state showing an embodiment of a lens barrel according to the present invention.

FIG. 2 is a sectional view of the embodiment in a tele state.

FIG. 3 is a perspective view of a connection flexible member in a wide state.

FIG. 4 is a perspective view of a connection flexure in a tele state.

FIG. 5 is an external view of a connecting flexible cable applied to the lens barrel of the present invention.

FIG. 6 is a sectional view showing a conventional lens barrel in a wide state.

FIG. 7 is a sectional view showing a conventional lens barrel in a telephoto state.

FIG. 8 is an external view of a connection flexible member used in a conventional lens barrel.

[Explanation of symbols]

 1 Camera Body 10 2 Group Board 13 Shutter Unit 14 Connection Flex 14a First Arm 14b Second Arm

Claims (1)

[Claims] 1. A lens having a zoom lens for changing a focal length by changing a distance between a plurality of lens groups arranged on an optical axis, and a flexible printed circuit board for transmitting an electric signal from one of the lens groups. In the lens barrel, the flexible printed circuit board has one end fixed to a shutter unit integrated with the lens group and the other end fixed to a moving member having a small movement amount with respect to the lens group, and deformed into a U-shape by the movement of the lens group. A first arm portion, one end of which is connected to the moving member and the other end of which is connected to a control circuit of the camera body, and which is deformed into a U shape by the movement of the moving member.
A lens barrel characterized by comprising an arm portion of the lens barrel.