JPH11153819A - Synchronous switch for camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the malfunction of a synchronous switch caused by vibration or impact. SOLUTION: When a shutter button is depressed, a shutter blade 58 is turned to open an exposure aperture 57. In the midst of turning, the blade 58 hits and elastically deforms a movable metallic armature 78 so as to bring it into contact with a fixed metallic armature 79. A regulation part 84 preventing the armature 79 from being elastically deformed in a direction where it approaches to the armature 78 by the vibration or the impact is integrally formed with a holding member 80 and arranged between the armatures 78 and 79. The regulation part 84 allows the armature 79 to be elastically deformed in the direction where it is separated from the armature 78.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synchro switch for operating various devices such as a strobe in conjunction with the rotation of a kick blade type shutter blade.

[0002]

2. Description of the Related Art A lens-equipped film unit in which a photographic film is preliminarily incorporated in a unit body incorporating a simple photographic mechanism so that photographing can be easily enjoyed at any time is available. This film unit with a lens includes, for example, "Sharan Run Super800 (product name)"
Various types, from those incorporating only the basic photographing mechanism such as, to those equipped with a strobe device such as "Sharp Run Flash (trade name)" and enabling nighttime or indoor shooting The user can select one according to the application.

The structure of a lens-fitted photo film unit is simplified in order to reduce the cost, and a kicking type shutter device is generally used. The kicking-type shutter device is configured such that the shutter blade is axially attached to the shutter base in a state where the shutter blade is spring-biased in the closing direction, and one end of the shutter blade is kicked off by a shutter driving lever that is displaced in response to a shutter release operation. The shutter blade is rotated in the opening direction against the bias of the spring, and thereafter the shutter blade is returned to the closed position by the bias of the spring.

FIG. 4A shows a shutter blade used in a film unit with a lens and a synchro switch of a strobe device. The shutter blade 2
One end is rotatably mounted on a shaft 3 provided in the film unit with a lens, and a disc portion 4 formed at the other end shields an exposure opening 5 facing an exposure surface of the photographic film. An exposure opening 5 is provided in the vicinity of the shaft bladed portion of the shutter blade 2.
One end of a pull-back spring 6 for urging the shutter blade 2 in a direction of shielding the shutter blade 2 is locked. The other end of the pullback spring 6 is locked to the main body of the film unit with a lens. When the shutter button is pressed in the lens-fitted film unit, the shutter drive lever 7 constituting the shutter mechanism kicks the projecting portion 2a of the shutter blade 2 and is shown by a two-dot chain line against the urging of the pullback spring 6. The shutter blade 2 is rotated toward the position.

The synchro switch 9 is arranged laterally on the rotation surface of the shutter blade 2, and when rotating in a direction to open the exposure opening 5, a pressing piece formed on the upper portion of the shutter blade 2. The movable metal contact piece 11 that is hit by the pressing piece 10, the fixed metal contact piece 12 that the movable metal contact piece 11 that is hit by the pressing piece 10 and elastically deforms, and the movable metal contact piece 11 and the fixed metal contact piece 12 And a holding member 13 made of plastic which is held in an insulated state. This sync switch 9
The movable metal contact piece 11 and the fixed metal contact piece 12 are electrically connected to the strobe circuit by using the holding member 13 and attached to the printed circuit board on which the strobe circuit is formed. Then, when the movable metal contact piece 11 and the fixed metal contact piece 12 come into contact with each other, the strobe circuit is turned on, and strobe light emission is performed.

[0006]

However, when vibration or impact is given by dropping the film unit with a lens or the like, as shown in FIG. 4B, the movable metal contact 11 and the fixed metal contact 12 Have a problem that they are elastically deformed and come into contact with each other, so that strobe light emission is performed.

In addition, a printing mechanism for printing a bit mark corresponding to a photographing screen size designated by a user at the time of photographing on a photo film, confirming the bit mark at the time of printing, and creating a print photograph of a designated size, and It has been proposed to incorporate an imprint circuit into a film unit with a lens. In this film unit with a lens, the use of a synchro switch of a strobe device has been considered in order to obtain the timing for activating the imprinting circuit.However, if the above-mentioned problem with the synchro switch occurs, an erroneous bit mark is generated. It is imprinted on the photo film.

In order to solve the above problem, as shown in FIG. 5A, an extension 13a for holding the fixed metal contact piece 12 is formed on a holding member 13, and as shown in FIG. Fixed metal contact piece 12 when vibration or impact is given
It has been considered to reduce the amount of deformation of the tip portion so as not to contact the fixed metal contact piece 11. However, in this method, the rigidity of the fixed metal contact piece 12 increases, and the elasticity of the movable metal contact piece 11 and the fixed metal contact piece 12 causes the shutter blade 2 to rotate to the closed position together with the retraction spring 6. There is a problem that the shutter speed becomes faster than the set value.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to prevent a malfunction of a camera synchro switch due to vibration or impact.

[0010]

SUMMARY OF THE INVENTION In order to solve the above problems, a camera synchro switch according to the present invention is provided between a movable metal contact and a fixed metal contact, the movable sync contact being in contact with the fixed metal contact. A restricting member is provided that prevents elastic deformation in a direction approaching the metal contact piece and allows elastic deformation in a direction in which the fixed metal piece moves away from the movable metal contact piece. Further, the regulating member is formed integrally with the holding member attached to the printed circuit board while holding the movable metal contact piece and the fixed metal contact piece, so that it can be adopted at low cost.

[0011]

FIG. 2 shows the appearance of a film unit 2 with a lens according to the present invention. On the front surface of the film unit 15 with a lens, a photographing lens 16, an object-side finder window 17, a strobe light-emitting unit 18 for strobe light emission, a charging operation member 19 for switching the strobe unit on and off, and a viewfinder range are switched. A finder switching operation knob 20 is provided.

An opening 24 through which a shutter button 21, a counter window 22 for displaying the number of remaining images that can be taken, a display light guide 23 for displaying the completion of strobe charging is projected, A display opening 25 is provided for displaying the roll-up of all the photographic films and the completion of the closing of the light shielding cover of the film cartridge. Also, from the rear side of the film unit 15 with a lens, a winding knob 26 that is rotated for each frame is exposed, and the eyepiece side finder window 27 is located at a position facing the objective side finder window 17 (see FIG. 3). Is provided.

As shown in FIG. 3, a film unit 15 with a lens includes a main body 31 in which a film cartridge 30 comprising a photographic film 28 and a substantially cylindrical cartridge main body 29 is mounted, and a front surface of the main body 31. Exposure unit 32 and strobe unit 33 to be assembled
And a front cover 34 and a rear cover 35 that are assembled so as to cover the front side and the back side of the main body 31.

A spool 36 to which one end of the photographic film 28 is locked is rotatably incorporated in the cartridge body 29, and further has a built-in film feeding mechanism as disclosed in Japanese Patent Application Laid-Open No. 6-266053. ing. Further, a stick-shaped light-shielding cover 37 that opens and closes the film entrance and exit by being rotated from the outside is incorporated in a film entrance and exit (not shown) through which the photo film 28 enters and exits the cartridge main body 29 in place of the conventional telephone. ing.

The photographic film 28 includes two large and small perforations 3 having different sizes along one side edge.
9, 40 are alternately arranged at two kinds of intervals. The perforations 39 and 40 are used to set the leading and trailing sides of each frame 41 in the film feeding direction.
Is rolled into the cartridge body 29,
The large perforations 39 indicate the leading side in the film feeding direction, and the small perforations 40 indicate the rear side.
The perforations 39 and 40 are provided by the number corresponding to the number of the frames 41.

At the center of the front surface of the main body 31, there is provided a light-shielding tube 43 for shielding the photographing optical path from the exposure unit 32 mounted on the front surface to the photographic film 28. A photo film 28 is provided on the back side of the light shielding tube 32.
An aperture for defining the exposure range to the substrate is formed. The rear cover 35 has a film support surface 35b curved so as to face the aperture.

The photographing lens 16 is provided on the front side of the light shielding tube 43.
Aperture 31 for guiding transmitted subject light to aperture
b is formed. Further, an opening 31a for exposing a sprocket incorporated in the exposure unit 32 toward the photographic film 28 is formed above the light shielding tube 43. On both sides of the light-shielding cylinder 43, a cartridge chamber 45 and a film roll chamber 46 for accommodating the cartridge body 29 and the rolled photographic film 28 at the manufacturing stage are integrally formed.

The cartridge chamber 45 and the film roll chamber 46 have a rear cover 35 attached to the back side of the main body 31, and a bottom lid 48 for the cartridge chamber integrally formed with the rear cover 35, and a film roll chamber 46 for the film roll chamber. By closing the bottom cover 49, an appropriate light shielding ability is obtained. In addition,
The bottom lids 48 and 49 are connected to the rear cover 35 via a bendable thin portion, and the bottom lid 48 is opened when the film cartridge 30 is taken out of the used film unit 15 with lens.

At the upper part of the cartridge chamber 45, a winding knob 26 is rotatably mounted. The hoisting knob 26 has a gear formed on the outer periphery, and a drive shaft formed on the lower surface is engaged with the spool 36 of the cartridge body 29. Then, the photo film 28 is wound up by the spool 36 by being rotated counterclockwise in the drawing every time one frame is shot. Further, the winding knob 26 is prevented from rotating in the reverse direction by the engagement of the check pawl 51 formed on the upper surface of the cartridge chamber 45 with the gear.

On the upper surface of the cartridge chamber 45, the number of rotations of the winding knob 26 is counted, and the photographic film 28 is counted.
When the hoisting knob 26 is rotated by an amount corresponding to the entire volume of the cartridge
A light-shielding lid closing mechanism 53 for closing one light-shielding lid 37 is incorporated.

The exposure unit 32 is formed as a unit by assembling various components on a base portion 55 formed of plastic, and is removably assembled on the front surface of the light shielding tube 43. On the upper surface of the base portion 55, a plurality of components constituting a shutter mechanism are assembled, and an objective lens and an eyepiece constituting a finder optical system are assembled. A lens cover 56 for holding the taking lens 16 is attached to the front surface of the base portion 55, and the front surface of the base portion 55 between the lens cover 56 and the base portion 55 has a photograph as shown in FIG. An exposure opening 57 for exposing the film 28 is formed, and a shutter blade 58 for opening and closing the exposure opening 57 is swingably assembled.

A display light guide 23 for indicating the completion of charging of the strobe unit 33 is slidably attached to the exposure unit 32 in the vertical direction. The display light guide 23 is connected to the charging operation member 19.
Is projected outward from the upper surface of the film unit with lens 15 in conjunction with the sliding operation upward.

The strobe unit 33 includes a strobe circuit as various circuits, a printed circuit board 33a provided with an imprint circuit for imprinting a bit mark indicating a print size on the photographic film 28, and the strobe light emitting section 18 assembled thereto. Consists of When the charging operation member 19 provided on the front cover 34 is slid upward, the switch contact pieces 60a, 60a arranged on the front side of the printed circuit board 33a,
60b comes into contact with the contact portion of the printed circuit board 33a, thereby performing strobe charging. Also, the printed circuit board 3
3a, the strobe circuit and the imprint circuit are activated by turning on the shutter blade 58 in conjunction with the rotation of the shutter blade 58 to the open position, and the strobe unit 33 emits strobe light,
A synchro switch 62 for printing a bit mark is attached.

The front cover 34 includes a front cover body 64 in which the shutter button 21 and the display opening 25 are integrally formed.
The front cover 65 includes a front panel 65 attached to the center of the front surface of the front cover body 64, a field-of-view switching plate (not shown) incorporated between the front cover body 64 and the front panel 65, and the charging operation member 19. The field switching plate is rotatably mounted around the photographing optical axis between the front cover body 64 and the front panel 65, and is slid in an arc-shaped slit 70 formed in the front panel 65. The operation knob 16 is turned. A plurality of finder frames inserted and removed between the objective side finder window 18 and the finder optical system of the exposure unit 32 are integrally formed on the field switching plate. These finder frames limit the finder field of view to panorama, high vision, standard field of view, and the like.

In addition to switching the finder visual field, the visual field switching plate also switches a mark imprinting mechanism 72 for imprinting a bit mark representing a print size on the photographic film 28. The mark imprinting mechanism 72 is incorporated around the light-shielding tube 43 of the main body 31 and, although not shown in detail, has two imprinting openings provided so as to face out of the photographing range of the photographic film 28. A mark switching plate for selectively opening and closing two printing apertures in conjunction with the rotation of the visual field switching plate;
An imaging light guide that guides the imaging light to the imaging opening, a light-shielding cover that shields these from external light, a rotation lever, a slide lever, and the like that transmit the rotation of the field switching plate to the mark switching plate. Consists of Note that, as the light for imprinting, a light-emitting element constituting an imprinting circuit provided on the printed circuit board 33a is used.

As shown in FIG. 1A, the shutter blade 5
Reference numeral 8 denotes an exposure which is rotatably mounted at one end to a shaft 74 provided on the front surface of the base member 55 of the exposure unit 32, and which has a disk portion 58a formed at the other end to face the frame 41 of the photographic film 28. The opening 57 is shielded. Shutter blade 58
One end of a pull-back spring 75 for urging the shutter blade 58 in a direction of blocking the exposure opening 57 is locked in the vicinity of the shaft attachment portion. The other end of the pullback spring 75 is locked to the base member 55. When the shutter button 21 is pressed in the lens-fitted film unit 15, the shutter drive lever 76 constituting the shutter mechanism kicks the projecting portion 58b of the shutter blade 58 rightward in the figure,
The shutter blade 58 is rotated toward the position shown by the two-dot chain line in the figure against the bias of the pullback spring 75.

The synchro switch 62 includes a shutter blade 5
The movable metal contact piece 78 which is disposed laterally on the rotation surface of the shutter blade 8 and is hit by a pressing piece 58c formed on the upper part of the shutter blade 58 when rotating in a direction to open the exposure opening 57.
And a fixed metal contact piece 79 in which the movable metal contact piece 78 elastically deformed by being hit by the pressing piece 58c, and a plastic holding for holding the movable metal contact piece 78 and the fixed metal contact piece 79 in an insulated state. And a member 80. The sync switch 62 is provided with a printed circuit board 33a on which a flash circuit is formed by using a holding member 80, and a movable metal contact 78 and a fixed metal contact 79 are electrically connected to the flash circuit. The movable metal contact 78 and the fixed metal contact 7
9 contacts the strobe circuit and the imprinting circuit, and the strobe light emission and the imprinting of the bit mark are performed.

The shutter blade 58 is integrally formed with a restricting piece 82 disposed below the tip of the movable metal contact piece 78. The restricting piece 82 prevents the movable metal contact 78 from being elastically deformed and coming into contact with the fixed metal contact 79 when a vibration or an impact is applied to the lens-fitted film unit 15.

The holding member 80 of the synchro switch 62 is integrally provided with a regulating portion 84 which is disposed between the movable metal contact piece 78 and the fixed metal contact piece 79 and is in contact with the upper surface of the fixed metal contact piece 79. Is formed. This restriction part 84
As shown in FIG. 1 (B), when a vibration such that the movable metal contact piece 78 and the fixed metal contact piece 79 are elastically deformed upward is given to the film unit 15 with the lens, The elastic deformation of the contact piece 79 is regulated to prevent the contact with the movable metal contact piece 78. As a result, it is possible to prevent inadvertent strobe light emission, imprinting of an erroneous bit mark on the photographic film 28, and the like.

The restricting portion 84 contacts only the upper surface of the fixed metal contact piece 79. Therefore, the shutter blade 58
Even when the movable metal contact piece 78 and the fixed metal contact piece 79 are pressed by the pressing piece 58c when the is rotated to the open position, the fixed metal contact piece 79 can be elastically deformed downward as in the conventional case. Therefore, the shutter speed is not affected. As described above, since the regulating portion 84 is formed integrally with the holding member 80 that holds the movable metal contact piece 78 and the fixed metal contact piece 79, it is possible to adopt the low cost.

In the above-described embodiment, a film unit with a lens in which a film cartridge for feeding a photographic film out of the cartridge body by rotation of a spool is described as an example, but a lens unit with a conventional 135 type photographic film is mounted. It can also be used for a film unit.

The present invention can be applied to a camera using a synchro switch composed of a pair of metal contact pieces other than a lens-fitted film unit.

[0033]

As described above, according to the camera synchro switch of the present invention, the contact between the movable metal piece and the fixed metal piece due to vibration or impact can be prevented. The reliability of the camera used can be improved. Also, because of the low cost,
It can also be used in low-cost cameras and film units with lenses.

[Brief description of the drawings]

FIG. 1 is a front view showing the configuration of a synchro switch according to the present invention.

FIG. 2 is a perspective view showing the appearance of a film unit with a lens incorporating the synchro switch of the present invention.

FIG. 3 is an exploded perspective view showing a configuration of a film unit with a lens.

FIG. 4 is a front view showing a configuration of a conventional sync switch.

FIG. 5 is a front view showing the configuration of another conventional sync switch.

[Explanation of symbols]

 58 Shutter blade 62 Synchro switch 78 Movable metal contact piece 79 Fixed metal contact piece 80 Holding member 84 Regulator

Claims (2)

[Claims] A movable metal contact piece attached to a printed circuit board, electrically connected to various circuits, and elastically deformed by being hit by a shutter blade rotating in a direction to open an exposure opening; A synchro switch for a camera, comprising a fixed metal contact piece with which a metal piece contacts and operating various circuits in conjunction with the rotation of the shutter blade, wherein a fixed metal piece is provided between the movable metal piece and the fixed metal piece. A restricting member is provided which prevents elastic deformation in a direction approaching the movable metal contact piece by contacting the contact piece and allows elastic deformation in a direction in which the fixed metal piece moves away from the movable metal contact piece. Sync switch for camera. 2. The camera according to claim 1, wherein the regulating member is formed integrally with a holding member attached to a printed circuit board while holding the movable metal contact piece and the fixed metal contact piece. Sync switch.