JPH11337797A - Arrangement structure of flexible printed wiring boards - Google Patents

Abstract

(57) [Problem] To realize a lens barrel having a small size and a high photographing magnification, a flexible printed wiring board arranged in a multi-stage barrel does not need to have a complicated shape, and can be used for internal parts. Use an arrangement that minimizes interference. SOLUTION: A second guide cylinder 36 moves in the optical axis direction with respect to the first guide cylinder 32 on the inner diameter side of a first guide cylinder 32 fixed to the inner diameter side of an outer cylinder 33 integrated with a mount cylinder 31. A movable frame 39 which is supported so as to be able to hold the lens group L and the electromagnetic diaphragm device 40 on the inner diameter side of the second guide cylinder 36 is movably supported in the optical axis direction with respect to the second guide cylinder 36, and is a multi-step feeding lens. In the lens barrel, the electric circuit board 4 is attached to the second guide cylinder 36.
2 and a first and a second flexible printed circuit board 4 having one end connected to the electric circuit board 42 in a circumferential direction thereof.
The other ends of the tubes 3 and 44 are connected to the electric contacts 34 of the mount cylinder 31 and the electric components of the moving frame 39 with U-turn portions in different directions in the radial direction, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arrangement structure of a flexible printed wiring board used for a device having an electric circuit mounted in an interchangeable lens for a single-lens reflex camera.

[0002]

2. Description of the Related Art In recent years, a single-lens reflex camera has been mainly used for auto-focusing, and a motor for driving a focusing lens group, an electric circuit for controlling the motor, and a camera body are also used for an interchangeable lens attached to the camera. Electric circuits for performing various controls, such as electric circuits for exchanging and communicating information between lenses, are required. In addition, it is common to use a flexible printed wiring board to connect the above-described motor and the mounting board from the relation of wiring space. Further, when the above-mentioned motor or the like is attached to the movable lens group, an extra length is provided in advance to the flexible printed wiring board from the motor to the mounting board, and the movement of the movable lens group is caused by bending of the flexible printed wiring board. Means for absorbing by deformation are generally used. In particular, as this means, a flexible printed wiring board having a U-turn portion obtained by folding the flexible printed wiring board so as to have a curvature in the optical axis direction is arranged, and the movement of the U-turn portion on the flexible printed wiring board is performed. In order to absorb the amount of movement of the movable lens group, a connection means is often used.

FIG. 2 shows a conventional example of an interchangeable lens barrel in which a flexible printed wiring board having a U-turn portion as described above is arranged. That is, an outer cylinder 3 which is a part of the external appearance of a lens barrel by a screw or the like and a guide cylinder 2 arranged inside the mount cylinder 1 having a bayonet claw 1a for attachment to a camera body (not shown) are provided by a screw or the like. A rear end side is fixed via a flange portion 3a on the inner diameter side of the outer cylinder 3, and an electric circuit board 4 is fixed between the guide cylinder 2 and the mount cylinder 1. A cam cylinder 5 is fitted on the outer diameter surface of the guide cylinder 2, and a groove 5 a formed on the rear side of the cam cylinder 5 and a claw 2 a provided on the rear side of the guide cylinder 2 engage with the bayonet. 2
Is supported so as to be rotatable around the optical axis.

Further, a moving frame 6 for holding the lens group L and fixing the electromagnetic diaphragm device 7 is fitted on the inner diameter side of the guide cylinder 2, and at least one circumferential member is provided on the outer peripheral portion of the moving frame 6 in the circumferential direction. The rollers 8 are fixed by screws or the like, and the rollers 8 penetrate straight grooves 2 b parallel to the optical axis direction provided in the guide cylinder 2 and engage with cam grooves 5 b formed in the cam cylinder 5. doing. Then, the flexible printed wiring board 9 moves the electric terminals of the electromagnetic diaphragm device 7 and the electric circuit
A turn portion is formed and electrically connected. In order to form the U-turn portion, a guide plate 10 is fixed to a fixed portion such as an inner diameter portion of the guide tube 2 with a screw or the like, and a part of the flexible printed wiring board 9 is held.

In the conventional example having the above-described structure, when the cam barrel 5 is rotated around the optical axis by operating an operation member (not shown) of the lens barrel for zooming or focusing, the cam groove 5b and the guide are formed. The rollers 8 engaging with the rectilinear grooves 2b of the cylinder 2 allow the lens group L of the moving frame 6 and the electromagnetic diaphragm device 7
Is moved back and forth in the optical axis direction between the wide state in the lower half of the drawing and the telescopic state in the upper half of the drawing. At that time, the flexible printed wiring board 9 smoothly bends while changing the position of the U-turn part, To maintain a good electrical connection.

However, in recent years, macro photography has been taken up as a major field in single-lens reflex cameras, and the trend of interchangeable lenses capable of macro photography is to further increase the photographing magnification. Is accompanied by an increase in the amount of movement of some or all groups. A moving group having an aperture stop also requires a large moving amount. As a lens barrel structure for realizing this large amount of movement, a multi-stage feeding mechanism in which tubes arranged in a multiplex in the radial direction change the interval in the optical axis direction with each other is effective. The mechanism has problems that the size is easily increased in the radial direction of the lens barrel, and the power supply means to the electromagnetic diaphragm device fed by multi-stage feeding is complicated.

FIG. 3 shows a conventional example of a multi-stage extending barrel provided with a flexible printed wiring board having a U-turn portion in an interchangeable lens for a single-lens reflex camera. That is, an outer cylinder 13 which becomes a part of the external appearance of a lens barrel by a screw or the like at a front end side of a mount cylinder 11 having a bayonet claw 11a for attaching to a camera body (not shown) and a first guide cylinder disposed inside the outer cylinder 13 The rear end of the outer cylinder 13 is fixed via a flange 13 a on the inner diameter side of the outer cylinder 13. An electric circuit board 14 is fixed between the first guide cylinder 12 and the mount cylinder 11. A first cam cylinder 15 is fitted on the outer diameter surface of the first guide cylinder 12, and a groove 15a formed on the rear side of the first cam cylinder 15 and a claw section 12a provided on the rear side of the first guide cylinder 12 are engaged with a bayonet. The first guide cylinder 12 is supported so as to be rotatable around the optical axis.

Further, a second guide cylinder 16 is disposed on the inner diameter side of the first guide cylinder 12, and a projection 16 a provided at the rear end of the second guide cylinder 16 has an inner diameter surface of the first guide cylinder 12. Is engaged with the straight guide groove 12b extending in parallel with the optical axis direction, and is supported so as to be movable in the optical axis direction. A second cam cylinder 17 is fitted on the outer diameter surface of the second guide cylinder 16, and the second cam cylinder 1
7, a groove 17a provided on the inner diameter surface near the rear end is bayonet-coupled to a claw portion 16b provided on the outer diameter surface of the second guide cylinder 16, and is rotatable around the optical axis with respect to the second guide cylinder 16. And at least one first roller 18 at the rear of the outer peripheral portion.
Are fixed by screws or the like, and the first roller 18 passes through a rectilinear groove 12b provided in the first guide cylinder 12 and parallel to the optical axis direction, into a cam groove 15b formed in the first cam cylinder 15. Is engaged.

A moving frame 19 holding the lens group L and fixing the electromagnetic diaphragm device 20 is fitted on the inner diameter side of the second guide cylinder 16. At least one second roller 21 is fixed in the direction by a screw or the like, and the second roller 21 passes through a rectilinear groove 16b provided in the second guide cylinder 16 and parallel to the optical axis direction. 17 is engaged with a cam groove 17 b formed in the cam groove 17. The flexible printed wiring board 22 electrically connects the electric terminals of the electromagnetic diaphragm device 20 and the electric circuit board 14 by forming two U-turn portions on the way. This U
In order to form a turn portion, a first guide plate 23 is fixed to a fixing portion such as an inner diameter portion of the first guide tube 12 with a screw or the like, and a part of the flexible printed wiring board 22 is held. The second guide tube 16 has a second fixed portion such as an inner diameter portion.
The guide plate 24 is fixed by screws or the like, and holds a part of the flexible printed wiring board 22.

In the conventional example having the above structure, when the first cam barrel 15 is rotated around the optical axis by operating an operation member (not shown) of the lens barrel for zooming or focusing, the cam groove 15b is formed. And the straight groove 12b of the first guide cylinder 12
The second cam cylinder 17 is advanced and retracted in the direction of the optical axis while rotating around the optical axis via the first roller 18 that engages with. Since the second guide cylinder 16 supports the second cam cylinder 17 so as to be rotatable around the optical axis, and is supported by the linear guide groove 12b with respect to the first guide cylinder 12 so as to be able to advance and retreat in the optical axis direction. The second cam barrel 17 moves in the optical axis direction by the same amount as the amount of movement in the optical axis direction. The second roller 21 is provided in the straight guide groove 16 of the second guide cylinder 16.
b and the cam groove 17b of the second cam barrel 17, it is moved in the optical axis direction by the rotation of the first cam barrel 15, and the lens group L of the moving frame 19 and the electromagnetic diaphragm device 20 are moved. The flexible printed wiring board 22 is advanced and retracted in the optical axis direction between the wide state of the lower half of the drawing and the telescopic state of the upper half of the drawing. It is designed to stay connected.

[0011]

However, in the conventional example of the above-described multi-stage extending barrel, since the extending amount of the lens group L is large, the length of the flexible printed wiring board becomes extremely long. There has been a problem that the deflection of the wiring board cannot be completely absorbed and the wiring board is easily clogged.

The present invention solves the above-mentioned problems of the conventional example,
It is an object of the present invention to provide a structure for disposing a flexible printed wiring board in a multi-stage feeding barrel in order to obtain a lens barrel having a small size and a high photographing magnification.

[0013]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention is to fix an electric circuit mounting board to an intermediate cylinder member movably supported in the optical axis direction in a multi-stage extension lens barrel. Two flexible printed wiring boards extend from the mounting board, and the other ends of both flexible printed wiring boards have U-turn portions in different directions, and are fixed cylindrical members which are respectively engaged with the outer periphery and optical axes which are engaged with the inner periphery. It is fixed to a moving cylinder member that moves in the direction.

[0014]

According to the present invention, there is provided a first cylindrical member having a cylindrical shape, and a second cylindrical member movable with respect to the first cylindrical member in a direction along the center of the cylindrical member. A third barrel member configured to be movable in a direction along the center of the cylinder with respect to the second barrel member.
The electric circuit mounting portion in which the electric component is mounted on the cylindrical member is connected to the second
A first flexible printed wiring board fixed to extend substantially in a circumferential direction of the tubular member and having a first flexible printed wiring board and a second flexible printed wiring board extending from the electric circuit mounting portion; The other end of the board is fixed to the first tubular member, the other end of the second flexible printed wiring board moves with the third tubular member, and the first and second flexible printed wiring boards are connected to the electric circuit. By having a U-turn portion that can be bent in different directions in the radial direction of the cylindrical member with respect to the mounting portion, a flexible printed wiring board having a complicated shape can be used even in a macro lens or the like with a large extension amount without the need. , Easy to place.

[0015]

An embodiment of the present invention will be described below with reference to FIG. FIG. 1 shows an interchangeable lens for a single-lens reflex camera.
FIG. 4 is a cross-sectional view illustrating a structure for disposing a flexible printed wiring board in a lens barrel having a multi-stage feeding mechanism. In the figure, reference numeral 31 denotes a mount cylinder having a bayonet claw 11a for attaching to a camera body (not shown), and an electric contact 34 for performing communication and power supply with the camera is fixed. 32 is a first guide cylinder, the rear end of which is fixed with screws or the like. Reference numeral 33 denotes an outer cylinder, which is a part of the external appearance of the lens barrel.
A is fixed to the mount cylinder 31 with screws and the like together with the first guide cylinder 32 disposed on the inner side with respect to a. 35 is the first
The cam cylinder is fitted on the outer diameter surface of the first guide cylinder 32, and the groove 35a formed on the rear side thereof and the claw part 32a provided on the rear side of the first guide cylinder 32 are bayonet-engaged. The first guide cylinder 32 is supported rotatably around the optical axis.

Reference numeral 36 denotes a second guide cylinder, which is disposed on the inner diameter side of the first guide cylinder 32, and a projection 36a provided at the rear end thereof is parallel to the optical axis direction formed on the inner diameter surface of the first guide cylinder 32. And is movably supported in the optical axis direction. Reference numeral 37 denotes a second cam cylinder, which is fitted on the outer diameter surface of the second guide cylinder 36 and has a groove 3 provided on the inner diameter surface near the rear end thereof.
7a is bayonet-coupled to a claw 36b provided on the outer diameter surface of the second guide cylinder 36, and is supported rotatably around the optical axis with respect to the second guide cylinder 36. One first roller 38 is fixed by a screw or the like, and the first roller 38 passes through a straight groove 32 b provided in the first guide cylinder 32 and parallel to the optical axis direction, and is attached to the first cam cylinder 35. It is engaged with the formed cam groove 35b.

Reference numeral 39 denotes a moving frame which is fitted on the inner diameter side of the second guide cylinder 36, holds the lens unit L and fixes the electromagnetic diaphragm device 40, and has at least one circumferentially extending outer peripheral portion thereof. Two second rollers 41 are fixed by screws or the like, and the second rollers 41 are formed in the second cam cylinder 37 through straight grooves 36 b provided in the second guide cylinder 36 and parallel to the optical axis direction. Engaged with the cam groove 37b. Reference numeral 42 denotes an electric circuit board, which is fixed to an inner peripheral portion of the second guide cylinder 36 in a substantially circumferential direction. Reference numeral 43 denotes a first flexible printed wiring board, which electrically connects the electric circuit board 42 and the electric contacts 34 provided on the mount cylinder 31 by forming one U-turn portion 43a in the middle. Reference numeral 44 denotes a second flexible printed wiring board, which electrically connects the electric terminals of the electromagnetic diaphragm device 40 and the electric circuit board 42 by forming one U-turn portion 44a in the middle. Reference numeral 45 denotes a guide plate which is fixed to a fixing portion such as an inner diameter portion of the first guide cylinder 32 with a screw or the like, and is provided with a first flexible printed wiring board 4.
3 and a part of the U-turn part 43a for holding the shape.

In the conventional example having the above structure, when the first cam barrel 35 is rotated around the optical axis by operating an operation member (not shown) of the lens barrel for zooming or focusing, the cam groove 35b is formed. And a straight groove 32b of the first guide cylinder 32
The second cam cylinder 37 is advanced and retracted in the direction of the optical axis while rotating around the optical axis via the first roller 38 engaging with. The second guide cylinder 36 supports the second cam cylinder 37 so as to be rotatable around the optical axis, and is supported by the linear guide groove 32b so as to be able to advance and retreat in the optical axis direction with respect to the first guide cylinder 32. The second cam barrel 37 moves in the optical axis direction by the same amount as the amount of movement in the optical axis direction. Further, the second roller 41 is provided in the straight guide groove 36 of the second guide cylinder 36.
b and the cam groove 37b of the second cam barrel 37, it moves in the optical axis direction by the rotation of the first cam barrel 35, and moves the lens group L of the moving frame 39 and the electromagnetic diaphragm device 40. The flexible printed wiring boards 43 and 44 are bent while changing the positions of the U-turn parts 43a and 44a in the optical axis direction between the wide state of the lower half of the drawing and the telescopic state of the upper half of the drawing. , To keep the electrical connection.

Then, the electric circuit board 42 is connected to the second guide cylinder 3.
6, the flexible printed wiring board for connecting the electromagnetic diaphragm device 40 and the electric circuit board 42 for controlling the same is formed by the first flexible printed wiring board 43 having a simple and short U-turn portion 43a. Can connect. In addition, due to the arrangement of the electric circuit board 42, the position limitation of the U-turn portion at the rear portion of the lens barrel is eliminated,
The flexible printed wiring board can be bent more smoothly. Further, the first flexible printed wiring board 43 and the second flexible printed wiring board 44 are separated from the electric circuit board 42 in directions different from each other by the U-turn portions 43a.
And 44a, it is possible to simplify the shape of the flexible printed wiring boards 43 and 44, and to efficiently arrange the flexible printed wiring boards with less interference with components in the lens barrel. It is possible to prevent the strength of the part from being reduced due to the notch.

[0020]

In the above embodiment, the first guide tube 32 is the first tube member of the present invention, the second guide tube 36 is the second tube member of the present invention, and the moving frame 39 is the present invention. In the third tubular member, the electric circuit board 42 is in the electric circuit mounting portion of the present invention, the first flexible printed wiring board 43 is in the first flexible printed wiring board of the present invention, and the second flexible printed wiring board 44 is in the 2 Flexible printed circuit boards
Each corresponds. The above is the correspondence between each configuration of the embodiment and each configuration of the present invention. However, the present invention is not limited to the configuration of this embodiment, and has the functions described in the claims or the configuration of the embodiment. Any configuration that can achieve the function may be used.

[0021]

As described above, according to the first aspect of the present invention, a first cylindrical member having a cylindrical shape and a first cylindrical member which is movable with respect to the first cylindrical member in a direction along the center of the cylinder. In a lens barrel having two cylindrical members and a third cylindrical member configured to be movable in a direction along the center of the cylinder with respect to the second cylindrical member, an electric component is mounted on the second cylindrical member. An electric circuit mounting portion is fixed so as to extend substantially in a circumferential direction of the second cylindrical member, and has a first flexible printed wiring board and a second flexible printed wiring board extending from the electric circuit mounting portion. The other end of the first flexible printed wiring board is fixed to the first tubular member, and the other end of the second flexible printed wiring board moves together with the third tubular member, and the first and second flexible printed wiring boards are moved. The flexible printed circuit board is By having U-turn portions that can be bent in different directions in the radial direction of the members, a flexible printed wiring board with a complicated shape is not required even for a macro lens with a large amount of extension, and a simple arrangement of the flexible printed wiring board In addition, it is possible to reduce notches for preventing interference of the lens barrel part by the flexible printed wiring board, and it is possible to prevent a decrease in the strength of the lens barrel.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a lens barrel having an arrangement structure of a flexible printed wiring board according to an embodiment of the present invention, wherein an upper half is in a telephoto state and a lower half is in a wide state.

FIG. 2 is a longitudinal sectional view of a lens barrel having a structure in which a conventional flexible printed wiring board is provided, wherein an upper half is in a telephoto state and a lower half is in a wide state.

FIG. 3 is a longitudinal sectional view of another conventional lens barrel having an arrangement structure of a flexible printed wiring board, in which an upper half is in a telephoto state and a lower half is in a wide state.

[Explanation of symbols]

31..mounting cylinder, 32..first guide cylinder, 33..outer cylinder, 34..electrical contact, 35..1st cam cylinder, 36 ..
2nd guide cylinder, 37 ··· second cam cylinder, 38 ··· first roller,
39: moving frame, 40: electromagnetic diaphragm device, 41: second
Rollers, 42... Electric circuit board, 43... 1st flexible printed wiring board, 43a... U-turn section, 44... 2nd flexible printed wiring board, 44a... U-turn section, 45.

Claims (1)

[Claims] A first cylindrical member having a cylindrical shape, a second cylindrical member configured to be movable in a direction along a cylindrical center with respect to the first cylindrical member, and a cylindrical member with respect to the second cylindrical member; A lens barrel having a third cylindrical member configured to be movable in a direction along the center, wherein an electric circuit mounting portion in which an electric component is mounted on the second cylindrical member is substantially in the circumferential direction of the second cylindrical member. A first flexible printed wiring board and a second flexible printed wiring board fixed so as to extend from the electric circuit mounting portion, and the other end of the first flexible printed wiring board is The other end of the second flexible printed wiring board is fixed to the first tubular member, and the other end of the second flexible printed wiring board moves together with the third tubular member, and the first and second flexible printed wiring boards are moved with respect to the electric circuit mounting portion. Can be bent in different directions in the radial direction of the cylindrical member An arrangement structure of a flexible printed wiring board having a U-turn portion.