JPH02254428A - Camera with aperture diameter regulating device - Google Patents

Abstract

PURPOSE:To constantly and properly set the diaphragm diameter of a lens system and to eliminate the need for the use of a complicated and high- performance lens system by controlling the displacement quantity of an electromagnetic actuator responding to a focal distance change with a regulating cam. CONSTITUTION:A zooming operation is performed responding to an object distance before exposure and a movable barrel member is moved to a setting position. Integrating with the motion, an adjusting cam 22 acts on the regulating cam 18, which advances to the displacement locus of the electromagnetic actuator 1 by prescribed quantity. At the next stage, the actuator 1 is started for the exposure operation, displaced in a normal direction along the displacement locus and abuts on the cam 18. Then the displacement quantity in the normal direction is regulated. Consequently, the maximum opening amount of blades 14 and 15 is decided. Through a series of these actions the diaphragm diameter of the lens system can be controlled responding to the focal distance change accompanied with the zooming operation.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides a zero dynamic focusing function (hereinafter referred to as AF), a mechanism for automatically controlling the exposure aperture and exposure time of the shutter (
The present invention relates to a compact camera equipped with functions such as AE (hereinafter referred to as AE) and a function capable of zooming according to the subject distance (hereinafter referred to as zoom), and particularly relates to the regulation of the shutter aperture diameter.

[Conventional technology]

Conventionally, in the above-mentioned type of compact camera, in order to continuously open and close the shutter blade, a drive device capable of generating drive torque in both forward and reverse directions, such as a moving magnet type electromagnetic actuator or stepping motor, is used to operate this drive torque. AE was performed by transmitting it to the blades through a mechanism. In addition to the AE mechanism, it was equipped with a zooming mechanism for zooming.

[Problem that the invention seeks to solve]

However, conventional cameras equipped with a zoom lens system with a lens shutter use a system in which the aperture diameter of the lens system remains constant regardless of changes in focal length due to zooming, which eliminates the need for complicated aperture diameter regulation. I've lost it. However, on the other hand, the aperture value (F value) is F - aperture diameter /
Since it is determined by the focal length, in the case of a lens with a large zoom ratio, if the aperture diameter is constant, the F value will differ between the short focal length side and the long focal length side. For this reason, in order to obtain a lens that is bright even on the long focal length side, which is required as a recent trend in the market, or has a small F value, the aperture must be quite large on the short focal length side, which tends to be inferior in terms of image quality. It is had. This reduces the degree of freedom in lens design, and in order to ensure performance, the number of lenses must be increased, and shapes and dimensional accuracy that are not suitable for mass production are required, which has a negative impact on the ability to make cameras smaller and lower in cost. Also, if such a high-performance lens system is not used,
Because the diameter of the aperture cannot be adjusted in response to changes in focal length, there is a problem in that it is difficult to obtain photographic images of a certain quality or better for the reasons mentioned above.

SUMMARY OF THE INVENTION In order to solve the problems of the prior art, it is an object of the present invention to provide a compact camera that can adjust the aperture diameter according to changes in focal length using a simple mechanism.

[Means to solve the gap]

A camera device to which the present invention is applied has a movable blade member that continuously opens and closes a lens system in order to simultaneously determine an exposure aperture and an exposure time, and an actuation mechanism that engages with and operates the blade member. . A drive mechanism is engaged with the actuation mechanism. The drive mechanism is continuously displaced in both forward and reverse directions along a predetermined locus, and when the blade member is displaced in the forward direction, the blade member is opened via the actuating mechanism, and when the blade member is displaced in the reverse direction, the blade member is opened in the same manner. Performs shutoff operation. The vane member and actuation mechanism are mounted on the base plate. Further, a cylindrical member is disposed around the substrate, which is interlocked with at least a portion of the lens system and is movable as the focal length changes due to zooming.

The camera device according to the present invention further includes a regulating member that enters the displacement locus of the drive mechanism and regulates the forward displacement amount to determine the maximum opening operation amount of the blade member during exposure. is disposed on the substrate, and includes an adjusting member fixed to the movable cylinder member and acting on the regulating member as the movable cylinder member moves to adjust the amount of entry of the regulating member into the displacement locus.

[For production]

According to the present invention, first, prior to exposure, a zooming operation is performed in accordance with the subject distance, and the movable barrel member is moved to a set position. Together with this movement, the adjusting member acts on the regulating member, and the regulating member enters the displacement locus of the drive mechanism by a predetermined amount.

Next, the drive mechanism is started for the exposure operation, and is displaced in the forward direction along the displacement locus, but eventually comes into contact with the regulating member and the amount of forward displacement is regulated. As a result, the maximum opening actuation amount of the blade member is determined. Through this series of actions, the aperture diameter of the lens system can be controlled in accordance with changes in focal length due to zooming.

Generally, the smaller the focal length, the smaller the maximum opening operation amount is controlled, and the amount is determined by the performance of the lens system.

〔Example〕

Preferred embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is an exploded perspective view of the shutter section and its surroundings that perform AE among the components of the camera device according to the present invention. As shown in the figure, the drive mechanism is composed of, for example, a moving magnet type electromagnetic actuator 1, and a drive bin 2 is disposed on the lower surface of the actuator 1, which is displaced along a predetermined trajectory with a predetermined torque in both forward and reverse directions as shown by the arrow. is installed.

The actuation mechanism consists of an actuation lever 3, which has a shaft hole 4 and an elongated hole 5 that engages with the drive pin 2.

Furthermore, operating pins 6 and 7 are installed on the lower surface of the operating lever 3 at a distance from the shaft hole 4. The operating lever 3 is the drive bin 2
According to the displacement, the shaft hole 4 is also oscillated in both forward and reverse directions along a predetermined locus around the shaft hole 4.

The substrate 8 has at its center an opening 9 for a lens system and escape holes IO and 11 for allowing the operating pins 6 and 7 to escape to the lower surface side. Further, on the upper surface of the substrate 8, a shaft pin 12 and another shaft pin 13 that engage with and are pivotally supported by the shaft hole 4 of the operating lever 3 are provided. A pair of blades 14 and 15 (not shown) are arranged on the lower surface side of the substrate 8.

The blade 14 is provided with a shaft hole 16 and an elongated hole 17.

The blade 14 is rotatably mounted on the base plate 8 through a shaft hole 16 and is engaged with the operating pin 7 through an elongated hole 17. By swinging the operating lever 3, the blade 14 moves in both directions, opening and closing, relative to the opening 9, thereby performing shuttering.

Now, the regulating member for regulating the displacement of the drive bin 2 of the actuator 1 is composed of a regulating cam 18 and has a shaft hole 19. The regulating cam 18 is rotatably engaged with the vial 13 on the base plate through the shaft hole 19 in the direction indicated by the arrow. Further, the regulating cam 18 has a first cam surface 20 and a second cam surface 21 that enter the displacement locus of the drive bin 2 and come into contact with it.

Further, an adjusting member for adjusting the angular position of the regulating cam 18 to JyJ is composed of an adjusting cam 22 arranged around the base plate 8. The adjustment cam 22 is fixed along the inner circumferential direction of a movable cylindrical member (not shown), and moves as shown by the arrow in unison with the circumferential movement of the movable cylindrical member.

The adjustment cam 22 has a cam surface 23, and the second
The angular position of the regulating cam 18 is adjusted by coming into contact with the cam surface 21 of the regulating cam 18.

FIG. 2 is a plan view of the shutter section and its surroundings as seen from the bottom surface of the board after the parts shown in FIG. 1 are assembled, and shows the aperture in a fully open state, and FIG. 3 similarly shows the aperture in a fully open state. Second
As shown in the figure, a pair of blades 14 and 15 rotatably supported by a common shaft pin 24 provided on the base plate 8 are connected to the central portion of the base plate by actuating pins 7 and 6 mounted on the actuating lever 3, respectively. The opening 9 is held at the rest position with the opening 9 fully open. Further, the actuating lever 3, which is pivotally supported around the shaft pin 12, is also held by the drive pin 2 of the actuator 1 at the extreme rest position in the clockwise direction in the drawing. Furthermore, the drive pin 2 of the actuator 1 is also placed in the extreme clockwise rest position in the drawing.

In this state, the adjusting cam 22 fixed to the movable cylindrical member 25 disposed around the periphery of the substrate 8 is placed in a predetermined position as the movable cylindrical member 25 moves in the circumferential direction during zooming, and the cam surface 23 of the regulating cam 18 second cam surface 2
It is in contact with 1. As a result, the angular position of the regular cam 18 is set according to the change in focal length due to zooming. According to the set angular position, the first cam surface 20 of the regulating cam 18 enters into the forward displacement locus of the drive bin 2 of the actuator, and the first cam surface 20 and the drive bin at the (*11- position) move into the forward displacement locus of the drive bin 2 of the actuator. 2 defines the amount of forward displacement of the drive bin 2.

In this example, the adjusting cam 22 fixed to the movable cylinder member 25 is used to adjust the regulating cam 18, but instead of this, a pushing member such as the adjusting pin 22° is used as shown in FIG.
You can also use The adjustment pin z2° is linked to the movable cylindrical member 25 by a holding means (not shown) and comes into contact with the regulating cam 18 to determine its angular position.

FIG. 3 is a plan view of the pair of blades 14 and 15 moved from the rest position shown in FIG. 2 to the fully open position. As shown in the figure, by actuating the actuating lever 3 counterclockwise from its rest position, the pair of blades 14 and 15 move in opposite directions from each other with the common support pin 24 as a fulcrum and the opening 9
The user moves in the direction of retreat from the center and fully opens the opening 9. ;J3]
The actuation of the roots J4 and 15 takes place via elongated actuating pins 7 and 6 provided in these vanes. On the other hand, the actuating lever 3 is swung counterclockwise, that is, in the forward direction, along a predetermined locus by the drive pin 2 of the actuator about the shaft pin 12 . At this time, the drive pin 2 is also displaced counterclockwise, ie, in the forward direction, from its rest position along a predetermined locus.

By the way, in the case shown in FIG. 3, the first cam surface 20 of the regulating cam 18 comes into contact with the drive pin 2 of the actuator to regulate it when the apex vanes 14 and 15 reach the fully open position. It has become. Therefore, in this case, the aperture diameter of the lens system is controlled to match the full aperture diameter of the shutter in accordance with the change in focal length due to zooming.

However, in order to further reduce the aperture diameter of the lens system in response to a change in focal length, the movable barrel member 25 is rotated further clockwise, and is pushed by the cam surface 23 of the adjustment cam 22 to the first position of the regulation cam 18. The cam surface 20 enters deeper into the displacement locus of the drive pin 2.

As a result, the first cam surface 20 of the regulating cam 18 further approaches the drive pin 2 at the rest position, and the amount of forward displacement of the drive pin decreases. As a result, the blades 14 and 15 are stopped by contact between the drive pin 2 and the first cam surface 20 of the regulating cam 18 before reaching the fully open position, and the desired maximum opening operation amount and the desired shutter 1380 diameter are achieved. can be obtained.

FIG. 4 is a developed cross-sectional view showing the main parts of the camera device according to the present invention, and shows part of the AF mechanism, AE mechanism, and zoom mechanism. The lens system includes a lens group 26 on the object side (only a portion shown), a second lens group 27 in the middle, and a third lens group 28 on the film side (only a negative portion shown). Front frame 29
and the rear frame 30 are arranged apart from each other, and the zoom guide 3
It is guided by 1. A front lens barrel 32 and a rear lens barrel 33 that hold the second lens group 27 are arranged between the front frame 29 and the rear frame 30, and are movable in the optical axis direction with respect to the front and rear frames 29 and 30. There is.

The AF mechanism includes an AF stepping motor 34 fixed to the front frame 29, an AF cam 37 arranged in the rear frame 30 and driven by the stepping motor 34 via a pinion gear 35 and a transmission gear 36, and front and rear lens barrels 32 and 33. An AF pin 38 passes through and is fixed to the front lens barrel 32 and abuts the AF cam 37, and an AF pin 38 is fixed along the axial direction between the front and rear frames 29 and 30 to prevent the front and rear lens barrels 32 and 33 from moving in the axial direction. AF guide 39 to guide and front and rear lens barrels 3
2 and 33 toward the rear frame 30.

Next, the zoom mechanism includes a member (not shown) for moving the lens group 2B and/or the third lens group 28 along the axial direction and changing the focal length of the lens system by manual or automatic zooming operation. It is comprised of the above-mentioned movable cylindrical member, ie, the zoom ring 25, which rotates in the circumferential direction in accordance with the operation of this member, and the above-mentioned adjustment cam 22, which is attached or integrated with the zoom ring 25.

Finally, the AE mechanism includes the above-mentioned electromagnetic moving actuator 1 mounted on the rear frame 30, the above-mentioned regulation cam 18, actuation lever 3 and a pair of blades 14, which are respectively arranged in base number 8.
．． It consists of 15.

Next, referring to FIG. 4, the operations of the camera device according to the present invention will be explained in the order of AF, zoom, and AE.

In the AF operation, the distance to the object is first measured by a distance measuring means (not shown) in the camera body, and signal pulses corresponding to a predetermined number of stages suitable for the distance are supplied from the drive control circuit to the AF stepping motor 34. AF stepping motor 34
rotates and outputs torque to the pinion 35 and transmission gear 3.
6 to rotate the AF cam 37. Furthermore, AF cam 3
The initial rest position of No. 7 is set to top dead center or bottom dead center according to the specifications of the camera. The AF bin 38 is pushed up as the AF cam 37 rotates, and the front lens barrel 32 moves integrally with the AF pin 38 via the threaded portion of the AF guide 3.
Move forward along 9. At this time, the rear lens barrel 33 also moves at the same time. However, the front frame 29 and the rear frame 30 do not move in the axial direction. What moves are the front and rear lens barrels 32 and 33.
and vanes 14 and 15, etc. Also, the front and rear lens barrels 32,
In order to accurately control the amount of axial forward movement of the lens barrels 32, 33, the lens barrels 32, 33 are always biased rearward by a spring member 40. In the case of a compact camera, the maximum movement amount of the second lens group 27 for AF described above is about 3 mm from 2III11, and this maximum movement amount is divided into dozens of steps to perform fine focus adjustment.

Next is the zoom operation, but first the external zoom operation member (
(not shown) according to the subject distance.
Alternatively, the third lens group 28 is moved along the axis to set a desired focal length. In response to this operation, the zoom ring 25 rotates in the circumferential direction, and the adjustment cam 22 fixed to this rotates the regulation cam 18.
The regulating cam 18 is caused to enter the displacement locus of the drive bin 2 by a predetermined amount.

Finally, AE operation is performed. The electromagnetic actuator 1 starts in response to desired exposure amount information and exposure time information sent from an exposure control circuit (not shown), and the drive pin 2 moves forward along a predetermined trajectory from its rest position. .

In accordance with this, the operating lever 3 and the blades 14, 15 are interlocked and exposure is started. Eventually, the drive pin 2 comes into contact with the restriction cam 18, and its forward movement is restricted, and the blades 14, 15 are held at the maximum opening position. After the exposure is completed, the drive bin 2 is displaced in the opposite direction and returns to the rest position, thus completing the camera operation. It goes without saying that depending on the exposure aperture, the amount of movement of the drive pin 2 may not reach the maximum aperture, and therefore the drive pin 2 may return to the rest position without coming into contact with the regulating cam 18.

〔Effect of the invention〕

As described above, according to the present invention, the amount of displacement of the electromagnetic actuator can be easily controlled by the regulating cam according to changes in the focal length, so the aperture diameter of the lens system can always be appropriately set, and therefore, the aperture diameter of the lens system can be set appropriately. This has the effect that there is no need to use a high-performance lens system.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of a lens shutter section of a camera device according to the present invention, FIG. 2 is a plan view showing the lens shutter section shown in FIG. 1 in a fully open state, and FIG. 3 is a diagram also showing a fully open state. FIG. 4 is a developed sectional view along the optical axis of the essential parts of the camera device according to the present invention, and FIG. 5 is a perspective view showing another embodiment of the adjustment member according to the present invention. 1... Actuator, 2... Drive pin, 3...
...Operating lever 8...Platform, 14, 15...Blade, 22...Adjustment cam, 25...Zoom ring. 6.7... Operating bin, 9... Opening, 18... Regulating cam, 24... Common shaft bin, Figure 1 Applicant: Cor Co., Ltd. 2 Figure 3 Figure 5

Claims (1)

[Scope of Claims] 1. A blade member that opens and closes the lens system to determine the exposure aperture and exposure time, an actuation mechanism that engages with and operates the blade member, and the actuation mechanism. By engaging with the blade member and displacing it in both forward and reverse directions along a predetermined trajectory, the blade member is opened via the operating mechanism when the blade member is displaced in the forward direction, and the blade member is opened via the operating mechanism when the blade member is displaced in the reverse direction. A driving mechanism for performing a shielding operation, a substrate member for holding the blade member and the operating mechanism, and a substrate member disposed around the substrate member and interlocking with at least a part of the lens system to adjust the focal length. In a camera device having a cylindrical member that moves with the drive mechanism, the substrate member enters the displacement locus of the drive mechanism and regulates the amount of forward displacement thereof to determine the maximum opening actuation amount of the blade member. and an adjusting member that is fixed to the movable cylindrical member and acts on the regulating member as the movable cylinder member moves to adjust the amount of entry of the regulating member into the displacement locus. camera equipment. 2. The camera device according to claim 1, wherein the drive mechanism comprises an electromagnetic moving actuator including a drive pin that engages with the actuation mechanism and is continuously displaced in both forward and reverse directions along a predetermined locus. 3. The camera device according to claim 2, wherein the regulating member comprises a regulating cam rotatably mounted on the substrate member and regulating the amount of forward displacement of the drive pin. 4. The movable barrel member comprises a zoom ring that rotates in the circumferential direction of the lens system, and the adjustment member comprises an adjustment cam surface member provided along the inner circumferential surface of the zoom ring and abuts on the regulation member. 1. The camera device according to 1. 5. The camera according to claim 1, wherein the movable barrel member comprises a zoom ring that rotates in the circumferential direction of the lens system, and the adjusting member comprises a pushing member fixed inside the zoom ring and acting on the regulating member. Device.