JPH10104723A - Optical instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively eliminate the influence of magnetic leakage from a film feeding motor on a magnetic head, without increasing the scale of an optical instrument main body by providing a magnetic shielding function in a light shielding plate for limiting luminous flux in a photographic optical path with which a film is exposed. SOLUTION: A photographic lens barrel 11 for limiting the luminous flux in the photographic optical path is extended forward in such a manner that a pawl part, 11a is engaged with a moving diaphragm 12, when the lens barrel 11 is in a photographing possible state. The state of the lens barrel 11 is detected by a switch 28. When the lens barrel 11 is in a photographing state, before film feeding drive is executed, the lens barrel 11 is driven to collapse by a motor 13, so that the moving diaphragm 12 is moved to forcedly enter into the side of the magnetic head 8. The moving diaphragm 12 is brought close to the side of the magnetic head 8, to more effectively prevent a magnetic flux leaked from the film feeding motor. After the lens barrel is collapsed, the feeding motor is driven to wind the film, for starting the reading of film magnetic information. In other words, the moving diaphragm 12 is used as a magnetic shield body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical apparatus such as a camera having a magnetic head for inputting and outputting information to and from a magnetic layer provided on a film. It is about the shield.

[0002]

2. Description of the Related Art When one frame is photographed in an optical device such as a camera which can use a film cartridge provided with a magnetic layer on a film, a film feed motor starts rotating to feed one frame. During that time, for example, date and photographing information are written by a recording magnetic head. When reloading a film cartridge in use and feeding the film to unused frames, for example, check the presence or absence of magnetic recording on the magnetic layer using a reproducing magnetic head, and feed the film to a frame where no magnetic recording exists. We are going to send.

[0003] Since recording on the magnetic layer of the film and reading of information from the magnetic layer are performed during the feeding of the film,
When an electromagnetic motor is used as the feed motor, the effect of magnetic flux leakage from the film feed motor affects the magnetic head, and in particular, since the magnetic signal recorded on the magnetic layer is weak, a noise magnetic field is applied to the read head for the magnetic signal. Is a problem.

To solve the above problem, Japanese Patent Laid-Open Publication No.
No. 98, JP-A-6-332604, a configuration in which a film feed motor is arranged inside a film take-up spool, and a magnetic shield is arranged outside the motor, and the film take-up spool itself is made magnetic. It has been proposed to consist of a shield.

[0005]

However, in the above conventional example, the diameter of the take-up spool is inevitably increased in order to provide sufficient magnetic shielding. On the contrary, the shielding is weakened to reduce the spool diameter. When aiming, the distance between the magnetic read head and the hoisting motor had to be increased. In each case,
In order to suppress magnetic flux leakage from the motor only in the take-up spool, it is inevitable that optical devices such as cameras become larger.

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical system capable of effectively eliminating the influence of magnetic flux leakage from a film feeding motor to a magnetic head without increasing the size of an optical device body such as a camera. To provide equipment.

[0007]

According to a first aspect of the present invention, a magnetic head for writing or reading information to or from a magnetic layer provided on a film, and a photographing device for exposing the film. An optical device having a light shielding plate for restricting a light beam in an optical path, wherein the light shielding plate has a magnetic shielding function.

A second configuration for realizing the object of the invention according to the present application is a magnetic head for writing or reading information to or from a magnetic layer provided on a film, and restricting a light beam in a photographing optical path for exposing the film. An optical apparatus comprising: a light-shielding plate having a magnetic shielding function; and light-shielding plate driving means for moving the light-shielding plate to a position close to the magnetic head during a film feeding operation.

A third configuration for realizing the object of the invention according to the present application is a magnetic head for writing or reading information on a magnetic layer provided on a film, and a pad member for pressing the film against the magnetic head. And an optical device having a support means for supporting the pad member, wherein the support means has a magnetic shielding function.

A fourth structure for realizing the object of the invention according to the present application is a magnetic head for writing or reading information to or from a magnetic layer provided on a film, and a pad member opposed to the magnetic head. A supporting means for supporting the magnetic head and pressing the film against the pad member, wherein the supporting means has a magnetic shielding function.

In a fifth configuration for realizing the object of the invention according to the present application, in each of the above-mentioned configurations, the magnetic head is for reading and is arranged near the film cartridge chamber. In the equipment.

According to a sixth configuration for realizing the object of the invention according to the present application, in the first, second or fifth configuration described above, the light shielding plate is a diaphragm plate for flare-cutting light outside the photographing optical path. (Hereinafter simply referred to as an aperture plate).

[0013] A seventh configuration for realizing the object of the invention according to the present application is the optical apparatus according to the first or fifth configuration, wherein the light shielding plate is a screen size switching plate. .

In the above-described configuration, for example, an existing photographing light path light shielding plate (for example, an aperture plate or a panorama switching plate provided on the photographing lens barrel) disposed on the back side of the pad member facing the reading magnetic head is used. The noise field from the film feed motor can be prevented without increasing the size of the optical device body such as a camera, and the moving diaphragm plate is moved to the position close to the magnetic head especially when feeding the film where the noise magnetic field is generated. By moving, an excellent magnetic shielding effect can be obtained.

Further, by using the support means for supporting the pad facing the magnetic head or the support means for supporting the magnetic head as a magnetic shield, it is possible to feed the film without increasing the size of the optical device body such as a camera. A noise magnetic field from a transmission motor or the like can be prevented.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIG. 1 shows a first embodiment in which the optical apparatus of the present invention is applied to a camera.

FIG. 1 is an exploded perspective view of the camera showing the first embodiment. Reference numeral 1 denotes a film cartridge for housing a photographic film 2 having a magnetic layer. The film cartridge 1 can be rewound in the middle of shooting, and when it is detected by the magnetic head 8 described later that there is no recording on the magnetic layer after reloading, the film feeding is stopped at the frame of the magnetic layer.

Reference numeral 3 denotes a film feeding motor, which has a pinion gear 4 on a motor driving shaft. Reference numeral 5 denotes a hollow spool shaft for winding the film, and a film feed motor 3 is built in the hollow spool shaft. Reference numeral 6 denotes a fork gear, which receives power from a pinion gear 4 via a gear train (not shown) to drive a spool (not shown) in the film cartridge 1 engaged with the fork gear to push out the leading end of the film from the inside of the cartridge. In this case, the film is fed out in a thrust direction, and all the films are rewound into the cartridge. The pinion gear 4 transmits power to a spool 5 via a gear train (not shown) to wind up the film.

Reference numeral 7 denotes a part of a camera body (not shown), and reference numeral 7a denotes an aperture provided in a film exposure section of the camera body.

Reference numeral 8 denotes a magnetic head, which is a dual-purpose type that writes and reads magnetic information on the magnetic layer of the film 2, and is disposed between the film cartridge chamber and the aperture 7a. Reference numeral 9 denotes a pad placed at a position facing the magnetic head 8, and the back side has an elastic member 10 such as a leaf spring.
And presses the pad against the magnetic head 8.

Numeral 11 denotes a photographing lens barrel, numeral 12 denotes a movable stop for restricting the light flux of the photographing optical path which is linked to the movement of the photographing lens barrel 11, and numeral 13 denotes a photographing lens barrel driving motor.
Is driven from the retracted position to the photographing position.

Reference numeral 22 denotes a cart chamber cover for closing and closing a film cartridge chamber (not shown) (not shown).
23 is a switch that detects opening and closing of the cart room lid,
24 is a film cartridge loading completion detection switch, 1
Reference numeral a denotes a flange portion which is provided integrally with the spool of the film cartridge and which displays film information as a bar code. In the present embodiment, the patrone film information is, for example, information such as the number of frames that can be filmed, ISO sensitivity, film exposure state (unused, partially used, used, developed), negative / positive, and the like. Reference numeral 25 denotes a photoreflector for reading film information by utilizing rotation of a flange of a spool during film feeding. 26, a photoreflector for detecting the film position by film perforation; 28, a photographic lens barrel position detection switch for detecting the retracted position of the photographic lens barrel; 27, the feed motor 3, the photographic lens barrel drive motor 13, and the magnetic head 8. Patrone chamber lid open / close detection switch 23, film cartridge loading completion detection switch 24, film position detection photo-reflector 26 shooting lens barrel detection switch 28
Is a microcomputer that performs the above control.

FIG. 2 is a cross-sectional view of the first embodiment. In FIG. 2, members denoted by the same reference numerals as the members shown in FIG. 1 represent the same functions.

FIG. 2A shows the lens barrel in a photographable state. When the microcomputer 27 detects that the loaded film cartridge 1 presses the loading completion switch 24, the cart chamber lid (not shown) is closed, and the cart chamber lid close detection switch (not shown) is pressed, the supply of the cartridge (not shown) is performed. Power is transmitted from the pinion 4 to the fork gear 6 by the feed motor, and drives the film in the rewinding direction.

At this time, the flange 1a having a bar code display unit integrated with the spool rotates, and the film information written by this bar code is read out by the photo reflector 25. When the reading is completed, the film rewinding operation is stopped.

When the photographing lens barrel 11 is in a photographable state, the movable stop 12 is engaged with the claw 11a and is extended forward. The state of the lens barrel is detected by the switch 28, and if the camera is in the shooting state before the film feeding drive, the shooting lens barrel is moved to the motor 1 as shown in FIG.
The collapsible drive is performed in 3 to move the movable aperture 12 so as to push it toward the magnetic head 9.

By moving the movable diaphragm 12 closer to the magnetic head, it is possible to more effectively prevent magnetic flux leakage from the film feed motor. After collapsing the lens barrel, the feed motor is driven to wind up the film to start reading the film magnetic information.

FIG. 9 is an electric block diagram when the first embodiment is performed. Reference numeral 901 denotes a main switch for starting the control unit to a start-up state; 902, a cart room lid close detection switch; 903, a film cartridge loading completion switch; 904, a microcomputer as a control unit;
Reference numeral 905 denotes a photographing lens barrel driving means including a photographing lens barrel and a lens barrel driving motor, and 906 denotes a photographing lens barrel position detecting means for detecting the position of the photographing lens barrel. In FIG.

Reference numeral 907 denotes a film feeding means including a pinion gear 4, a spool 5, a fork gear 6, a feeding motor 3 and the like; 908, a film position detecting means corresponding to the photoreflector 26 for detecting film perforation; Reference numeral 910 denotes a magnetic head for writing or reading magnetic information on the film. Reference numeral 910 denotes film information reading means represented as the film information detecting photoreflector 25 in FIG. 1, but information can be read by a conventional DX contact piece or the like. If there is no problem.

FIG. 10 shows a sequence when the first embodiment is performed. In FIG. 10, when the closing of the lid of the cart chamber is detected (1001, YES), and when the loading of the cartridge is detected (1002, YES), a film information reading subroutine is entered (1003). In the present embodiment, the film information is detected by the photoreflector during the film rewinding of the barcode provided on the flange unit integrated with the spool, but the reading method using a known DX contact piece or the like is used. It can also be detected.

If there is no unexposed frame in the film exposure state obtained from this information (1004, NO), that is, if all the frames have been exposed or developed, the sequence ends. When there is an unexposed frame (1004, YES), if the switch 28, which is the lens barrel position detecting means, detects the retracted position (1005, YES), the magnetic head starts reading the film magnetic information (1006). . If the lens barrel is not collapsed (1005, NO), collapsing drive is started by the lens barrel driving means (1015), and if collapsing is completed (1016, YES), collapsing drive is terminated (101).
7), reading of magnetic information is started (1006).

Next, film winding is started using the film feeding means (1007). In film winding, not only the spool is wound and rotated, but also a fork gear is rotated to perform a film feeding drive. When the film is fed into the camera, the counting of the film frames by the film position detecting means is started (1008), and the film is fed to the last frame obtained from the patrone film information (1010).
(09, YES), the unexposed frame is detected by matching the presence / absence of magnetic information of the film frame with the frame or by judging from the magnetic information itself.

When the film is advanced to the last frame, the winding of the film is completed (1010), and the reading of the magnetic information is also completed (1).
011). Next, the film is rewound to the unexposed frame obtained from the magnetic information by the film feeding means (101).
2) When the unexposed frame comes to the photographable position (101)
3, YES), and end the film rewinding (101).
4) End the sequence.

In the above configuration, when the movable stop 12 is used as a magnetic shield, when reading the magnetic information recorded on the film, the movable stop is set to the retracted state shown in FIG. Is the most effective. Note that, in the first embodiment, only the movable stop 12 for ensuring proper exposure of the film surface when the photographing lens is moved in the optical axis direction is described as an example. Needless to say, it is effective also in the aperture.

(Second Embodiment) FIGS. 3 and 4 show a second embodiment of the present invention. FIG. 3 is an exploded perspective view of the camera and its cross-sectional view of FIG. In FIGS. 3 and 4, members having the same reference numerals as the members shown in FIG. 1 represent the same functions.

In FIG. 3, reference numerals 14a and 14b denote panoramic plates for limiting the light flux to be exposed on the film and changing the size of the light to be exposed. The panorama plate is formed by a magnetic shield and is located just before the aperture 7a. Are arranged in mesh with the panorama plate drive gear 15. Reference numeral 16 denotes a shooting frame switching lever for changing the size of the film surface exposed to light, and as shown in FIG.
4a and 14b are moved in the direction of the arrow that narrows the aperture frame.

In the second embodiment, the panorama plate 14
Since a and 14b are magnetic shields, the magnetic head 8
The panorama plate 14b at a position facing the film feeder effectively removes a noise magnetic field due to leakage magnetic flux generated when the film feed motor is driven.

In FIG. 4, the panorama plates 14a, 1
Although the position of 4b is changed by the lever 16, the imaging surface portion facing the magnetic head 8 is always covered irrespective of the change of the position, so that it functions as a magnetic shield regardless of the variable imaging frame.

(Third Embodiment) FIG. 5 shows a third embodiment of the present invention.
An embodiment will be described.

FIG. 5 is a cross-sectional view showing only the magnetic device of the camera, and 17 is a pad support plate for elastically pressing the film 2 against the magnetic head 8 while holding the pad 9. One end of the support plate is caulked to the main body 7. In the present embodiment, since the pad support plate 17 is formed of a magnetic shield, the magnetic flux leaked by the feeding motor or the like on the projection surface facing the magnetic head while satisfying the function of pressing the pad 9 against the magnetic head 8 is satisfied. Can be effectively removed.

(Fourth Embodiment) FIG. 6 shows a fourth embodiment of the present invention.
It is a cross-sectional view showing the embodiment. In the third embodiment shown in FIG. 5 described above, the magnetic shield constituting the pad support plate 17 may be made of permalloy if it is metal,
Silicon steel is used, but in general, bending stress is low,
The elastic member has a limited range of spring characteristics.

Therefore, in the present embodiment, the pad support plate 17 is formed of an elastic member such as a leaf spring, and a shield plate 18 serving as a magnetic shield is provided between the pad 9 and the support plate 17.
Is incorporated.

According to the present embodiment, similarly to the third embodiment, the magnetic flux generated by the feed motor or the like can be effectively removed at a position facing the magnetic head 8. of course,
If the pad support plate 17 can also be a magnetic shield, the magnetic shielding effect is further enhanced.

(Fifth Embodiment) FIG. 7 shows a fifth embodiment of the present invention.
It is a cross-sectional view showing embodiment.

Reference numeral 19 denotes a pad supporting case that supports the pad 9 in a floating manner, and reference numeral 20 denotes a spring that presses the pad 9 and the pad supporting case 19 against the magnetic head 8 with a film interposed therebetween. In the present embodiment, the pad support case 1
Reference numeral 9 denotes a magnetic shield, which effectively removes magnetic flux leakage from a feeding motor or the like on a projection surface facing the magnetic head.

(Sixth Embodiment) FIG. 8 shows a sixth embodiment of the present invention.
It is a cross-sectional view showing embodiment. In FIG. 8, 19
Is a pad support case that supports the pads 9 in a floating manner as in the fifth embodiment shown in FIG. 7, but the pads 9 as in the fifth embodiment shown in FIG. There is no elastic spring that presses the spring. However,
In the present embodiment, the magnetic head 8 is urged toward the pad 9 by the magnetic head support plate 21.
1 is a magnetic head, while the other end is a projection 7b of the main body 7.
Is fixed by a turtle.

In the present embodiment, since the pad support case 19 is a magnetic shield, the feed motor is effectively formed on the projection surface facing the magnetic head 8 as in the fifth embodiment shown in FIG. Magnetic flux leaked from the wire. Needless to say, if the head support plate 21 is also a magnetic shield, leakage magnetic flux can be more effectively prevented.

The above-described first to sixth embodiments can be combined with each other to more effectively prevent magnetic flux leakage from the feed motor.

If the above-described embodiments are combined with the method for preventing leakage magnetic flux around the spool shaft as proposed in JP-A-5-34798 or JP-A-6-332604, the spool shaft diameter is reduced. Can be prevented from leaking magnetic flux without making it extremely thick.

(Correspondence between Invention and Embodiment) In the above embodiments, the magnetic head 8 corresponds to the magnetic head of the present invention, and the movable diaphragm 12 and the panorama plates 14a and 14b correspond to the light shielding plates of the present invention. I do. The motor 13, the microcomputer 27, the control unit 904, the photographing lens barrel driving means 905, and the photographing lens barrel position detecting means 906 in the present embodiment correspond to a light shielding plate driving means. The pad 9 in the present embodiment corresponds to the pad member of the present invention, and the pad support plate 17,
The shield plate 18, the case 19, and the head support plate 21 correspond to the support means of the present invention.

The above is the correspondence between the components of the present invention and the components of the embodiment. However, the present invention is not limited to the configuration of the embodiment, and the functions described in the claims or It goes without saying that any configuration may be used as long as the function of the configuration of the embodiment can be achieved.

For example, the present invention can be applied to a cartridge of a type other than the cartridge described in the above embodiment, a cartridge having an image recording medium other than a film, and other types of cartridges.

In the present invention, the above embodiments and modifications, or their technical elements may be combined as necessary.

The present invention is also applicable to various types of cameras such as a single-lens reflex camera, a lens shutter camera, and a video camera.
Furthermore, for optical devices and other devices other than cameras, and further for those cameras, optical devices, and other devices, as well as devices that are applied to these cameras, optical devices, and other devices, or elements that constitute them Can be applied.

Further, the present invention is such that the whole or part of the configuration of the claims or the embodiments forms one device and is combined with another device. Or it may be something like an element constituting the device.

[0056]

According to the first or second aspect of the present invention, the magnetic flux is prevented from being leaked by the film feeding motor or the like by using the existing light shielding plate or pad supporting member. And good magnetic information can be read. In addition, it is easy to perform a countermeasure in combination with another countermeasure such as a countermeasure such as providing a magnetic shield on the outside of the spool shaft or the feeding motor.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a camera according to a first embodiment of the present invention.

FIGS. 2A and 2B are cross-sectional views of the camera shown in FIG. 1, wherein FIG. 2A shows a state in which a shooting barrel is extended, and FIG.

FIG. 3 is an exploded perspective view of a camera according to a second embodiment of the present invention.

FIG. 4 is a cross-sectional view of the camera of FIG.

FIG. 5 is a cross-sectional view of a third embodiment of the present invention.

FIG. 6 is a cross-sectional view of a fourth embodiment of the present invention.

FIG. 7 is a cross-sectional view of a fifth embodiment of the present invention.

FIG. 8 is a cross-sectional view of a sixth embodiment of the present invention.

FIG. 9 is a block diagram of an electric circuit of the camera according to the first embodiment.

FIG. 10 is a flowchart illustrating the operation of the camera according to the first embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Film cartridge 2 ... Film 3 ... Feeding motor 4 ... Pinion gear 5 ... Spool 6 ... Fork gear 7 ... Main body 7a ... Aperture 8 ... Magnetic head 9 ... Pad 10 ... Elastic member 11 ... Shooting lens barrel 12 ... Moveable aperture 13 … Barrel motor 14… Panorama plate 15… Panorama plate drive gear 16… Lever 17… Pad support plate 18… Shield plate 19… Pad support case 20… Spring 21… Head support plate

Claims (7)

[Claims] 1. An optical apparatus comprising: a magnetic head for writing or reading information on or from a magnetic layer provided on a film; and a light-shielding plate for restricting a light beam in a shooting optical path for exposing the film, wherein the light-shielding plate is An optical device having a magnetic shielding function. 2. A magnetic head for writing or reading information on or from a magnetic layer provided on a film, a light-shielding plate having a magnetic shielding function for restricting a light beam in a photographing optical path for exposing the film, and a film feeder. An optical device comprising: a light-shielding plate driving unit that moves the light-shielding plate to a position close to the magnetic head during operation. 3. An optical apparatus comprising: a magnetic head for writing or reading information to or from a magnetic layer provided on a film; a pad member for pressing the film on the magnetic head; and a support means for supporting the pad member. The optical device according to claim 1, wherein the support unit has a magnetic shielding function. 4. A magnetic head for writing or reading information to or from a magnetic layer provided on a film, a pad member arranged opposite to the magnetic head, and supporting the magnetic head to attach the film to the pad member. An optical device, comprising: a support unit that presses the optical device, wherein the support unit has a magnetic shielding function. 5. The optical apparatus according to claim 1, wherein the magnetic head is for reading and is arranged near a film cartridge chamber. 6. The optical apparatus according to claim 1, wherein the light shielding plate is an aperture plate for flare-cutting light outside the imaging optical path. 7. The optical apparatus according to claim 1, wherein the light shielding plate is a screen size switching plate.