JPH0456940A - Camera provided with zoom driving device - Google Patents

Abstract

PURPOSE:To reduce operating sound and vibration in a zooming operation by forming a part other than the output part of a zoom driving mechanism in sealed structure. CONSTITUTION:A driving system which drives a zoom lens-barrel is made into a unit, and the part other than the output part is formed in the sealed structure. In other words, a zoom unit is comprised of three baseplates A51, B52, and C53, and holds reduction gears 103-107 rotatably freely. In addition to that, the three baseplates A51, B52, and C53 are formed in the sealed structure except for positions engaging with the output part i.e. 107 and 108 in a connected state, which generates a muffling effect. Thereby, it is possible to make the operating sound of the zoom driving mechanism hard to be transferred to the outside.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a zoom lens drive system for a camera with a built-in zoom lens.

(Prior Art) In recent years, many compact cameras with built-in zoom lenses have been proposed, and many cameras of this type have a motor inside the camera and perform electrical zooming.

An example is shown in Figure 17. This zoom drive mechanism transmits the output of the motor 5 to the rotary gear 15 via the gear 7 to perform a zoom operation.

(Problem to be Solved by the Invention) Since the torque required to drive the lens barrel is normally large compared to the output torque of the motor 5, the torque of the motor is reduced through a reduction mechanism as shown in FIG. is being communicated to.

At this time, the motor rotates at a fairly high speed, so the operating noise and vibrations during zooming operations may give a strange feeling to the user.

SUMMARY OF THE INVENTION An object of the present invention is to provide a camera that performs electric zooming and has low operational noise and vibration during its zooming operation.

(Means for Solving the Problems) In order to achieve the above problems, the camera of the present invention has a zoom drive system. P! The structure is characterized by a sealed structure except for the output section. Furthermore, the zoom drive mechanism is held by an interference member made of an elastic body. Furthermore, the gear that rotates in the first stage of the motor with high rotation speed is made of helical teeth with a high meshing ratio.

(Printing) In the camera of the present invention, the above-described configuration makes it difficult for the operating sound of the zoom drive mechanism to be transmitted to the outside.

(Example) The present invention will be described in detail below with reference to the drawings.

The lens barrel unit F has the following configuration.

@2 As shown in Figure 2, the fixed barrel 4 is the positioning bin 4a,
b, and is fixed after being positioned in the positioning holes 3h and 3i of the front frame 3. As shown in FIG. 1, the rotating cylinder 1 is
It fits into the fixed tube 4 and is held rotatably around the optical axis. The rotary barrel 1 has a gear portion I11 around the optical axis, receives a rotational force from the outside, and the rotation causes the forward barrel 5 to move back and forth by a mechanism (not shown), thereby zooming the photographic lens. Further, as for the rotation ftJ1, the guide ring 2 whose inner surface 1b is guided by the bearing part 2f of the guide ring 2 is rotated through the holes 2a to d.
The mounts 9 of the front frame 3 are fixed to the parts 3a-d via the mounts 9 of the front frame 3.

Next, the Nisome drive unit will be explained.

As shown in Figure m1 and Figure 5, the drive motor 101 is fixed to the plywood A51. motor binion 102
is connected to the rotor of the motor and the spring by a kick spring 110, and a torque below a certain level is transmitted thereto.

In addition, the binion 102 is a stepped gear, and the reduction gear 1
It has a gear part 102a that meshes with 03 and a gear part 102b that meshes with another wheel 109. Furthermore, Binion 102
Because it rotates at high speeds, if the gear tooth shape or the accuracy between the shafts of the gears that mesh are poor, abnormal noise will be generated and the camera will look unsightly when the camera is in operation. Therefore, in this embodiment, a helical gear with an increased meshing ratio and a noise-reducing effect is used for the binion 102 and the reduction gear 103 meshing therewith.

The reduction gears 103 to 107 are rotatably held on shafts provided on the base plate A51 and the base plate C53, and transmit the driving force of the motor 101. Clutch 108 is clutch gear A10
aa, clutch gear B108b, spring 108C, Tsumugi 10
It is composed of four points 8d. clutch gear A108
a and B 108b have cam surfaces that engage with each other on a plane perpendicular to the rotation axis, and are pressed by a spring 108C to make the pongee 1
It is rotatably held at 08d. The shaft 108d is made of plywood A51f6! , are held in a shaft hole 2e provided on the guide ring 2. With the configuration described above, the driving force of the motor 101 is transmitted to the rotating cylinder.

Next, holding the zoom unit will be explained.

The zoom unit is made of three plywood A51. BS2. C53, as shown in Figure 5, 103 to 107
The reduction gear is rotatably held, and the three plywood sheets are combined to form a sealed structure except for the output part (the meshing position of 107 and 108), so as to have a noise-reducing effect. Furthermore, although the zoom unit is fixed to the front frame 3, as shown in FIG.
The clear sound effect is enhanced by fixing the front frame at the 3e lr tg position via the 70-taing support structure via the 70-teating support structure.

Next, the holding of the clutch 108 will be described. As shown in the t51 diagram and the fjsG diagram, the glaze 108b of the clutch 108
One of the gears is rotatably held in a shaft hole 2e provided on the guide ring 2, and the other is rotatably held in a hole 51b provided on the base plate A. As mentioned earlier, the inner surface 1b of the rotation 01 is received by the bearing part 2r of the guide ring 2, so the gear 1a of the rotation cylinder and the clutch gear 1
The distance between the shafts of 08a is compensated with high precision by the parts precision of the guide ring 2, and the two gears are stably held against the force acting in the direction of widening the distance between the shafts between the gear 1a and the gear 108a during driving. At the same time, the gear contact ratio is 311.
By increasing the space between 1 and 1, the risk of the gear becoming smaller and breaking can be avoided.

(Effects of the Invention) According to the present invention, as described above, the drive system that drives the zoom sharpener is made into a unit, and the parts other than the 8 force parts are made into a sealed structure, and the drive system is held in a 70-ring configuration. It is possible to reduce the sound of the camera so that the photographer does not feel strange.

[Brief explanation of the drawing]

Figures t51 to 6 show embodiments of the present invention, and m
Figures 1 and 2 are both exploded perspective views, Figure 30 is a vertical cross-sectional view when wide, Figure 4 is a vertical cross-sectional view when tele, ttSS diagram is an exploded cross-sectional view of the drive mechanism, Figure 6 (a) and (b
) is a partial cross-sectional view. 7 to 10 show a conventional example, where FIG. 7 is an exploded perspective view, FIG. 8 is a rear view, FIG. 9 is a longitudinal sectional view, and FIG.
The figures each show a partial sectional view. 51 to 53, 102 to 108... Drive mechanism patent applicant Minolta Camera Co., Ltd. Figure 10 Figure

Claims (2)

[Claims] (1) In a camera including a zoom lens, a drive mechanism that drives the zoom lens by a motor, and a holder that holds the zoom lens and the drive mechanism, the drive mechanism includes a portion other than a portion that transmits power to the zoom lens. A camera characterized by being sealed. (2) The camera according to claim 1, wherein the drive mechanism is fixed to the holder via an interference member made of an elastic body.