JPH0634866A - Driving device - Google Patents

Abstract

PURPOSE:To simplify the constitution of parts by providing a thrust regulator lest a driving member whose rotational force is transmitted through one rotating member should be rocked when the other rotating member slides by fitting in a cam ring directly connected. CONSTITUTION:The output gear 12a of a motor 12 for focusing is rotated and the rotation is transmitted to a focusing gear 8, which rotates on the outer periphery of the cam ring 5. The rotational force is transmitted to the focusing ring 2 by a focusing lever 4 coupled with the gear 8 with a screw, and a front group lens barrel 1 coupled with the ring 2 with a screw is moved back and forth in an optical axis direction corresponding to the rotating direction of the motor 12, so that focusing operation is performed. Meanwhile, the output gear 8a of a motor 8 for zooming is also rotated and driving force is transmitted to the cam 5. Thus, the cam ring 5 is rotated, and the front group lens barrel 1 and a rear group lens barrel 7 coupled with the cam groove of the cam ring 5 through rollers 14 and 18 are moved in the optical axis direction, thereby performing zooming action.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving device for driving first and second rotating members which are radially fitted to the outer circumference of a circular pipe.

[0002]

2. Description of the Related Art In a conventional drive device of this type, one of rotating members that are radially fitted to the outer circumference of a circular pipe is directly connected to the circular pipe, and the other rotating member slides on the outer circumference of the circular pipe. The rotating member is generally constructed so as to be safely floated above the circular pipe.

[0003]

However, in the above-mentioned conventional example, when one of the two rotary members radially fitted to the outer circumference of the circular pipe is rotated, the shape of the other rotary component becomes complicated. In addition, the component structure is such that the component strength is weak, and it is not easy to ensure component accuracy.

In addition, the number of parts in the component structure is large,
At the time of rotation of the rotary member that receives the rotational force transmitted from the actuator, the load torque increases, and the actuator also needs to have power, which causes a cost increase.

It is an object of the present invention to obtain a drive device that solves the above problems.

[0006]

The present invention is a drive device having the following structure. (1) First and second rotating members, which are radially fitted to the outer circumference of the circular pipe and to which driving force is transmitted from the actuators respectively, are provided. One of the rotating members is directly connected to the circular pipe and the other rotating member is By having the drive member that fits on the outer circumference of the circular pipe and that slides with the thrust backlash regulated, the component structure becomes simple and the precision of the component can be easily ensured. (2) Since the first and second rotating members have the same shape and have a structure that suppresses sliding, parts can be shared and the die allowance of die parts can be reduced. (3) By transmitting the driving force from the other rotating member to the driving member via the lever, the rotational load torque is reduced and the component cost is reduced to realize the cost reduction of the driving device.

[0007]

【Example】

Example 1. Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are diagrams in which the driving device of the present invention is applied to a lens driving device of an optical device. FIG. 1 is a sectional view and FIG. 2 is an enlarged sectional view of a main part thereof.

In FIGS. 1 and 2, L1 and L2 are a front lens group and a rear lens group, each of which comprises one or a plurality of optical lenses, and these two lenses form a two-group zoom optical system.

Reference numeral 1 denotes a front lens barrel which holds a front lens group L1. The front lens barrel 1 has a focus ring 2 and a screw 20.
And attached to the front group moving ring 3 by a helicoid. The front group moving ring 3 is radially fitted to the inner circumference of the main body cylinder 6 and is connected to the main body cylinder 6 by a roller 14 and a shaft screw 15 through a cam groove of the cam ring 5. Reference numeral 7 denotes a rear group lens barrel that holds the rear group lens L2, and this rear group lens barrel 7 is radially fitted to the inner circumference of the main body barrel 6 similarly to the front group lens barrel 1, and has a cam ring 5
Main body cylinder 7 by roller 18 and shaft screw 19 through the cam groove of
Is bound to.

A mount 13 is connected to the body cylinder 6 at the rear end thereof with screws 21. The motor base plate 10 is connected to the mount 13 with screws 22.
At 0, a motor 11 (for zoom) as an actuator and a motor 12 (for focus) as an actuator are attached.

Reference numerals 8 and 9 denote gears as first and second rotating members, which are radially fitted on the outer circumference of the cam ring 5 and mesh with the output gears 11a and 12a of the motors 11 and 12, respectively. 9 (a component common to the gear 8) is coupled to the cam ring 5 with a screw 23 so as to regulate the thrust. On the other hand, a focus lever 4 is coupled to the gear 8 with a screw 24, and the focus lever 4 is connected to the key groove 2 of the focus ring 2.
It is keyed to a. A focus rubber 16 is provided on the outer surface of the focus ring 2.

Next, the operation of the above configuration will be described.

First, when a voltage is applied to the terminal of the focusing motor 12, the output gear 12a of the focusing motor 12 rotates and is transmitted to the focusing gear 8. Therefore, the focus gear 8 rotates while sliding on the outer circumference of the cam ring 5. As a result, the focus lever 4 which is screwed to the focus gear 8 transmits the rotational force to the focus ring 2, and the front lens barrel 1 which is screwed to the focus ring 2 corresponds to the rotation direction of the motor 12. And moves back and forth in the optical axis direction to perform a focusing operation.

On the other hand, when a voltage is applied to the terminals of the zoom motor 8, the output gear 8a of the zoom motor 8 also rotates and the driving force is transmitted to the cam ring 5. As a result, the cam ring 5 rotates and the cam groove of the cam ring 5 and the roller 1
The front lens barrel 1 and the rear lens barrel 7 which are coupled by 4, 18 move in the optical axis direction to perform a zooming operation.

At the time of zooming, the focus gear 8 is set in a state where the cam ring 5 has a small frictional force, and the motor gear of the focus gear 8 is strengthened to transmit the rotational force to the focus ring 2. It is supposed not to be done.

[0016]

As described above, according to the present invention,
Thrust regulation is provided so that the driving member, which transmits the rotational force from the actuator through one rotating member, fits into the outer shape of the cam ring directly connected to the other rotating member and does not swing when sliding. Since the structure is used, the parts structure is simplified and it is easy to ensure the parts accuracy.

Further, since the first and second rotating members have the same shape and are structured to suppress the swing, the members can be shared, the parts structure can be facilitated, and the die allowance of the die parts can be reduced.

Further, since the rotational force to the rotating member is transmitted by the lever, there is an effect that the rotational load torque and the component cost are reduced and the cost of the driving device is reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of a lens driving device to which a driving device of the present invention is applied.

FIG. 2 is an enlarged view of a main part of FIG.

[Explanation of symbols]

 2 focus ring (driving member) 4 focus lever (lever) 5 cam ring (cylindrical) 8 focus gear (first rotating member) 9 zoom gear (second rotating member) 11 motor (actuator) 12 motor (actuator)

Claims (3)

[Claims] 1. A first and a second rotating member, which are radially fitted to the outer circumference of a circular pipe and to which driving force is transmitted from an actuator, respectively, one rotating member being directly connected to the circular pipe, and the other rotating member. A drive device characterized in that the member has a drive member that fits on the outer circumference of the circular pipe and that slides with thrust play being restricted. 2. The drive device according to claim 1, wherein the first and second rotating members have the same shape and have a structure for suppressing sliding. 3. The driving device according to claim 1, wherein the driving force is transmitted from the other rotating member to the driving member via a lever.