JPH01150109A - Zoom lens barrel - Google Patents

Abstract

PURPOSE:To obtain the miniaturization of a moving cylinder without necessitating to tighten a brush on the moving cylinder with a machine screw by performing the positioning of the tip of the brush and the zero position of a conductor pattern by jogging and adjusting a conductor pattern plate by using a rotary tool provided with an eccentric pin. CONSTITUTION:At the time of assembling a zoom lens barrel, the moving cylinder 21 is inserted to a fixed cylinder 20 after the conductor pattern plate 22 is inserted in the groove 20a of the fixed cylinder 20 and positioned. In the moving cylinder 21, the brush 24 is formed integrally, and fixed position adjustment is performed by jogging the conductor pattern plate 22 in the groove 20a in a forward and backward direction by using the rotary tool 25 so that the tip of the brush 24 can be positioned at a prescribed position on the conductor pattern 22a. After that, the rear end part of the conductor pattern plate 22 is inserted to the recessed part 23a of a circuit board 23, and also, a connection terminal 22c is jointed with a terminal 23c by soldering, and the circuit on the circuit board 23 is connected to the conductor pattern 22a electrically, and also, the conductor pattern plate 22 is jointed with the circuit board 23 mechanically.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a zoom lens barrel having a fixed barrel and a movable barrel fitted around the outer periphery of the fixed barrel and movable in the axial direction. More specifically, the present invention relates to a zoom lens barrel equipped with a novel electrical component mounting structure for mounting electrical components to the zoom lens barrel.

[Background of the Invention] A zoom lens barrel to be attached to a camera or the like has two members: a fixed barrel that moves relative to each other in parallel, and a movable member that is fitted around the outer periphery of the fixed barrel and is movable in the axial direction. The movable barrel is moved to an arbitrary position relative to the fixed barrel in response to an operation by a camera user.

Recent zoom lens barrels are equipped with a position detection device to electrically detect the position of the movable barrel, and the information on the movable barrel position electrically detected by the position detection device is processed by a microcomputer. It is designed to be input into an information processing device such as.

FIG. 6 is a schematic longitudinal cross-sectional view of a main part of a known zoom lens barrel. In the figure, 1 is a known mount equipped with a claw portion 1a for connecting to the camera body, 2 is a fixed cylinder having a cam groove 2a penetrated through its peripheral wall surface and connected to the mount 1, and 3 is a fixed cylinder body that is connected to the mount 1. This is a movable cylinder that is fitted onto the outer peripheral surface of the fixed cylinder 2 and can slide only in the axial direction. A threaded portion 3a is formed on the inner circumferential surface of the distal end of the movable cylinder 3, and a lune holding cylinder 4 having a threaded portion 4a on the outer circumferential surface that engages with the threaded portion 3a is attached to the movable cylinder 3. It is inserted so that it can rotate and move in the axial direction. A gear part 4b is formed on the outer circumferential surface of the tip end of the second lens holding cylinder 4, and an autofocus motor having a pinion 6 that slides relative to the gear part 4b in the axial direction and constantly meshes with the gear part 4b. 7 is fixed to the outer circumferential surface of the distal end of the movable cylinder 3. The second lens (2) fixed to the lens holding tube 4 is a focusing lens, and a focusing operation is performed by moving the holding tube 4 and the lens (2) in the optical axis direction by the motor 7.

A second lens holding tube 5 holding a second lens (2) is fitted on the inner circumferential surface of the distal end of the fixed tube 2 so as to be movable relative to the fixed tube 2 in the axial direction. A driven pin 5a protruding from the outer peripheral surface of the movable cylinder 3 is inserted into a cam groove 3c penetrating through the rear end peripheral wall surface of the movable cylinder 3 and a cam groove 2a of the fixed cylinder 2 so as to be relatively slidable. There is. When the movable cylinder 3 is moved along the axial direction relative to the fixed cylinder 2, the interaction between the cam grooves 2a and 3c and the driven pin 5a causes the second
The lens holding barrel 5 is moved in the axial direction relative to the fixed barrel 2 and the movable barrel 3 to perform a zooming operation.

Power is supplied to the autofocus motor 7 and control signals are transmitted to the motor 7 through a band-shaped flexible printed board 8 extending in the axial direction along the outer peripheral surface of the movable cylinder 3.
It is now carried out by The flexible printed board 8 passes through a circumferential slit penetrating the peripheral wall surface of the fixed cylinder 2, reaches the rear end of the fixed cylinder 2, and is attached to an annular circle fastened to the fixed cylinder 2 with screws 10. It is soldered to a plate-shaped non-flexible circuit board 9.

A groove 2b parallel to the axial direction is carved on the outer peripheral surface of the fixed cylinder 2, and a part of a position detection device (for detecting the position of the movable cylinder 3) is configured in the groove 2b. A flexible printed board 12 with a conductive pattern is fixed with adhesive, and the rear end of the flexible printed board 12 is bent through a notch in the peripheral edge of the circuit board 9 and then soldered to the circuit board 9. ing.

On the other hand, a brush 11 that comes into sliding contact with the conductor pattern on the flexible printed board 12 is fastened to a protrusion 3b on the outer peripheral surface of the rear end of the movable cylinder 3 with a screw 10b.
The brush 11, the flexible printed board 12, and a part of the circuit on the circuit board 9 constitute the position detection device. That is, when the movable cylinder 3 moves,
As the brush 11 slides into contact with the conductor pattern on the flexible printed board 12 and moves, the instantaneous position of the brush 11 is electrically detected by the detection circuit on the circuit board 9.

The screw insertion hole penetrated through the brush 11 is long in the optical axis direction (long in the left-right direction in FIG. It can be adjusted in the axial direction.

In the known zoom lens barrel as described above, the brush 11 is screwed to the outer peripheral surface of the movable barrel 3. Therefore, in order to form a deep screw hole in the movable barrel 3 for screw fixing, the brush 11 is fixed to the outer peripheral surface of the movable barrel 3. It is necessary to form the protrusion 3b on the outer peripheral surface of the body 3, and as a result, the maximum diameter of the movable barrel 3 increases, which is contrary to the basic design goal of reducing the diameter of the zoom lens barrel.

Furthermore, in the conventional device, a flexible printed board was used as the conductive pattern board that slides into contact with the brush 11, but it is difficult to precisely position the flexible printed board during installation, and it is difficult to automate the assembly. Therefore, in conventional devices that use a flexible printed board as the conductor pattern board, the initial contact position between the brush 11 and the conductor pattern can be adjusted by finely adjusting the flexible printed board as the conductor pattern board. It was not possible to set it.

[Object of the Invention] An object of the present invention is to provide an electrical component mounting structure for mounting an electrical component including a mutually sliding contact body to a device having two relatively moving members, and particularly An object of the present invention is to provide a new electrical component mounting structure in a mechanical device such as a zoom lens barrel, in order to eliminate the above-mentioned drawbacks in conventional zoom lens barrels.

[Summary of the Invention] The present invention provides a zoom lens barrel that has a fixed barrel and a movable barrel that is fitted around the outer periphery of the fixed barrel and is movable in the axial direction. An axial groove is formed in the surface, and a small diameter hole is bored in the bottom of the groove at a position eccentric from the groove center line, while a small diameter hole is formed in the groove with the groove center line as the center. A conductor pattern plate having a hole with a radius of curvature including the hole is inserted so as to slide along the longitudinal direction of the groove, and a large diameter portion that can rotate within the hole and a conductive pattern plate that has a radius of curvature including the hole are inserted into the small diameter hole. By inserting a rotary tool having an inserted pin portion into the hole and rotating it, the conductor pattern plate can be moved minutely within the groove for positioning. A brush that comes into sliding contact with the conductor pattern on the conductor pattern board is protruded from the end surface of the movable cylinder so as not to form a protrusion on the outer peripheral surface of the movable cylinder, and a circuit is electrically connected to the conductor pattern. A circuit board is arranged parallel to the end surface of the fixed cylinder, and a recess is formed in the circuit board into which one end of the conductor pattern board is inserted, and the brush and the conductor pattern are arranged in parallel with each other. The present invention is characterized in that the conductor pattern plate is electrically connected and fixed to the circuit board fixed to the fixed cylinder after the conductor pattern plate is positioned by minute movement of the conductor pattern plate. Therefore, the zoom lens barrel according to the present invention having the above configuration can be made smaller than a conventional zoom lens barrel of the same type.

[Embodiments of the Invention] The present invention will be described in detail below with reference to FIGS. 1 to 5.

1 to 3 are schematic diagrams of a first embodiment of a zoom lens barrel having an electrical component mounting structure according to the present invention. In FIGS. 1 and 2, 2° is a fixed cylinder as a first member, 21 is a movable cylinder as a second member, and 20a is an axial groove carved on the outer peripheral surface of the fixed cylinder 20. , 20b is a small diameter hole drilled in the bottom surface of the groove 2oa at a position offset to the side from the groove center line; 22 has a conductor pattern 22a on its surface and is inserted into the groove 20a so as to be relatively slidable; 23 is an annular disc-shaped circuit board in which a recess 23a into which one end of the conductor pattern board 22 can be inserted is formed; 24 is a circuit board formed on the circumferential surface of the movable cylinder 21 so as not to form a protrusion; This is a brush integrally molded with the cylindrical body 21. A hole 22b having a radius of curvature including the small-diameter hole 20b is formed through the conductor pattern plate 22, centered on the groove center line of the groove 20a, and when the conductor pattern plate 22 is positioned at a predetermined position within the groove 2Oa, The small diameter hole 20b is located within the hole 22b.

In addition, in FIG. 1, 2Qc is a cam groove of the fixed cylinder body 20, 21b is a cam groove of the movable cylinder body 21, and 21a is a cam groove of the movable cylinder body 2.
1, and parts labeled with the same reference numerals as in FIG. 6 represent the same parts as shown in FIG.

When assembling the zoom lens barrel as described above, the conductor pattern plate 22 is inserted into the groove 20a of the fixed barrel 20, and the conductor pattern plate 22 is temporarily positioned so that the small diameter hole 20b enters the hole 22b. After that, the movable cylinder 21 is fitted into the fixed cylinder 20. Next, the conductor pattern plate 22 is moved into the groove 2Oa using the rotating tool 25 shown in FIG.
After adjusting the fixing position by moving the conductor pattern board 22 by a small amount in the front and back direction, insert the rear end of the conductor pattern board 22 into the recess 23a of the circuit board 23 and connect the connection terminal 2 of the circuit board 23.
3c and the connection terminals 22c of the conductor pattern board 22 are soldered to electrically connect the circuit of the circuit board 23 and the conductor pattern 22a, and mechanically connect the conductor pattern board 22 and the circuit board 23. Note that the circuit board 23 may be fastened to the rear end surface of the fixed cylindrical body 20 in advance with screws 10b.

The rotating tool 25 includes a large diameter portion 25b inserted into the hole 22b of the conductor pattern plate 22, and an eccentric pin 25 protruding from the tip surface of the large diameter portion 25a and inserted into the small diameter hole 20b of the groove 20a.
a, and when the rotating tool 25 is rotated with the large diameter portion 25a inserted into the hole 22b and the eccentric bottle 25b inserted into the small diameter hole 20b, the rotating tool becomes eccentric. Since it is rotated around the pin 25b, the conductor pattern plate 22 is moved by a minute distance parallel to the longitudinal direction of the groove 20a, and as a result, the position of the conductor pattern plate 22 on the fixed cylinder 20 can be adjusted. .

As described above, in the electrical component mounting structure according to the present invention, the tip of the brush and the τ position of the conductor pattern are positioned by finely adjusting the conductor pattern plate. There is no need to fasten with screws, and therefore, there is no need to form deep screw holes in the movable cylinder for screw insertion, and the outer diameter of the movable cylinder can be reduced. Further, since the brush can be insert-molded into the movable cylinder when the movable cylinder is molded, the number of man-hours required for assembling the electrical parts can be reduced.

3 shows an embodiment of the circuit board 23, FIG. 3(a) is a front view of the circuit board 23 shown in FIGS. 1 and 2, and FIG. 3(b) is a modified version of the circuit board 23. A front view of the embodiment,
It is. When the recess 23a for inserting the conductor pattern board 22 is formed separately from the center hole 23b as shown in FIG. It is necessary to design the corresponding height H or higher, but if the thickness of the part cannot be made to the height H or if the strength of the part becomes low, please refer to Figure 3 (b). It is also possible to use a circuit board 23A in which the conductor pattern board insertion recess and the center hole are integrated as shown in FIG.

FIGS. 4 and 5 show modified embodiments of the electrical component mounting structure according to the present invention, and the parts indicated by the same reference numerals as in FIGS. 1 and 2 are the same as those in FIGS. This is the same as the embodiment shown in FIG.

In this embodiment, a plug 26 with a minus groove having an eccentric pin 26a is inserted into the hole 22b of the conductor pattern plate 22, and by rotating the plug 26 with a driver 27, the conductor pattern plate 22 is fixed to the fixed cylinder 20. Groove 2
It is possible to move a minute amount in the axial direction within 0a.

[Effects of the Invention] As explained above, the zoom lens barrel of the present invention has the following advantages:
By adjusting the fixing position of the conductor pattern plate forming one of the mutually sliding contact members, the initial position with the brush, which is the other mutually sliding contact member, can be set, so the fixing position of the brush is adjusted. As a result, there is no need to screw the brush to the relatively moving member, and the brush can be attached without protruding from the surface of the relative moving member. Therefore, in the zoom lens barrel of the embodiment, the outer diameter can be made smaller than that of conventional products, and the number of man-hours for assembling electrical parts can be reduced.

In addition, since a non-flexible hard board is used as the conductive pattern board instead of a flexible printed board, positioning and connection to the circuit board can be performed mechanically and automatically, thus automating the work of installing electrical components. can be achieved.

Note that although the illustrated embodiment shows only the case where the present invention is applied to a type of lens barrel in which the movable barrel is fitted around the outer periphery of the fixed barrel, the mounting structure of the present invention can be It is clear that the present invention can also be applied as an electrical component mounting structure for a device having a relative movement member.

[Brief Description of the Drawings] Fig. 1 is a schematic vertical sectional view of a first embodiment of a zoom lens barrel having an electrical component mounting structure of the present invention, and Fig. 2 is a schematic longitudinal sectional view of the zoom lens barrel shown in Fig. 1. 3 is a front view and a modified example of some of the components shown in FIGS. 1 and 2, and FIG. 4 is an exploded perspective view of the main parts of FIGS. 5 is an exploded perspective view of the zoom lens barrel shown in FIG. 4, and FIG. 6 is a longitudinal sectional view showing a partially modified embodiment of the zoom lens barrel shown in FIG. It is a schematic longitudinal cross-sectional view. 1...Mount, 2.20...Fixed barrel,
3.21... Moving barrel, 4... Second lens holding barrel, 5... Second lens holding barrel, 6... Pinion, 7... Autofocus motor, 8... Flexible Printed board, 9.23... Circuit board, 22... Conductor pattern board, 11 and 24... Brush. Figure 1 Figure 4 Figure 6

Claims (1)

[Scope of Claims] A zoom lens barrel having a fixed barrel and a movable barrel fitted around the outer periphery of the fixed barrel and movable in the axial direction, the outer circumferential surface of the fixed barrel including: An axial groove is formed, and a small diameter hole is bored in the bottom of the groove at a position eccentric from the groove center line, and the small diameter hole is included in the groove with the groove center line as the center. A conductor pattern plate having a hole with a radius of curvature inserted therethrough is inserted so as to be able to slide along the longitudinal direction of the groove, and a large diameter portion that can rotate within the hole and a conductor pattern plate that is inserted into the small diameter hole are inserted into the groove. By inserting and rotating a rotary tool having a pin portion into the hole, the conductor pattern plate can be slightly moved for positioning within the groove, and the conductor pattern plate can be moved slightly for positioning within the groove. A brush that comes into sliding contact with the conductor pattern on the plate is protruded from the end surface of the movable cylinder so as not to form a protrusion on the outer peripheral surface of the movable cylinder, and has a circuit that is electrically connected to the conductor pattern. A circuit board is arranged parallel to the end surface of the fixed cylinder, and a recess is formed in the circuit board into which one end of the conductor pattern board is inserted, and the brush and the conductor pattern are positioned relative to each other. A zoom lens barrel configured to electrically connect and fix the conductor pattern plate to the circuit board fixed to the fixed barrel after performing this by minute movement of the conductor pattern plate.